I need to screw into my wall but halfway in, it hits something hard

Question: I tried in different spots on the wall but same thing. Is the whole wall like that? I live in a concrete building but not soundproof. I am able to use screws on other walls.
Comment: your probably hitting concrete or brick. Im not sure since I can't see it.
Comment: There's no way we could tell what your wall is constructed of without more info. And, you should probably [take our tour](//diy.stackexchange.com/tour) so you'll know how best to participate here.
Answer: Sometimes a concrete wall will not have full-depth studs on it.  Instead it will have thin (sometimes only 3/4") firing strips attached to the concrete and the wallboard or paneling gets attached to those strips.  If you are using long screws, chances are good that you are just hitting the concrete.
One way to test this would be to drill a small hole where there is not a stud and probe the wall with the bit to see how deep it is.  If the wall is shallow and you have thin firing strips, hanging heavy objects on the wall can be a challenge because you will have to use special anchors and partially drill into the concrete or brick.  You have to know a little more about how the wall is built to know that drilling the concrete will be safe.
Answer: Generally, hitting a hard thing means STOP
There's a convention that says you can safely use 1-1/2" nails or screws without having to worry about nicking an electrical wire, water or sewer line.  Where one of those comes within 1-5/8" of the finished wall surface, there is supposed to be a metal plate guarding it. Precisely to warn hole-drillers like yourself that pressing further will damage utilities.
There may be construction types that create this effect unnecessarily, but you should stop unless you have data to support that.  Nailing a water supply pipe is not something you want to do!


Is it bad to leave the crock pot on "warm" (not low) all day?

Question: I just bought all the ingredients to make a soup in the crock pot. I was planning on having it cook all day, but I just realized the recipe only calls for it to cook on low for 3-4 hours. If I cook it on low for 3-4 hours, and then put it on warm before I leave for work, will it be a bacteria minefield or will it be warm enough to keep the food safe from bacteria?
Comment: What is the temperature of the "warm" setting?
Comment: I know it's the dregs of the internet, but I found a [Yahoo Answer](http://answers.yahoo.com/question/index?qid=20070819191105AAx8FMx) that says: "The answer [regarding the "warm" setting] is 150 degrees for my Rival 3 qt. Crock pot. Yours may vary depending the brand & size etc.  I filled 1/2 the pot w/water & put in a meat thermometer. After about 1-2 hours=110 degrees . After 8 hours=150 degrees." It might be worth replicating this experiment with your specific model.
Comment: Besides safety, water loss could conceivably be an issue. I'm guessing your soup has plenty of leeway there, and you could just dilute it later, but depending on how well the lid seals, some dishes might dry out more than you'd like over the course of a day.
Comment: You should also be aware that some of the new digital slow cookers will shut off if left alone for too long.  Read the reviews online, because it'll affect if it's safe for Kosher cooking.  (as you can't turn things on during the sabbath, so you start something in the crock pot the night before, and leave it going for 24 hrs)
Comment: Generally crockpots, at least modern crockpots, are setup to never be in the danger zone when on. This is why they can't be used for any level of sous vide. They overcompensate for safety. Expirementing with a thermometer to know your actual temp is THE best way to know though.
Answer: I suspect "warm" is meant to maintain temperature, rather than raise it. My crock pots are too ancient to have anything other than "high" and "low", so I can't assert any real authority. However, if you reach 145F within the first hour at the highest setting, then keep it at "warm", and test the temperature after about 30 minutes with an instant-read thermometer and it stays around 140-160F, you'll probably be fine. Personally, I'd test the temperature first by cooking water.
If the temperature stays above 140F at low, the worst risk you'll have is overcooking. Beans  and vegetables like carrots and celery can overcook fairly easily in a crock pot, but higher collagen meats meant for stews tend to be fine when cooked for extended periods. Most crock pot recipes for stews and soups usually hold fine when at low for a full workday, although that's presuming a somewhat 70s-era soup aesthetic, which is probable for a crockpot recipe.
However, I would be inclined to attempt the recipe using the low setting rather than reducing it to warm, if you're not going to test the temperature first. If it turns out to be overcooked, you can always puree the ingredients with a blender...
I also doubt that switching to "warm" would be dramatically less likely to overcook the food than "low", unless it holds at a pretty stable 140F, and low ends up somewhere around 160F.
Answer:
will it be a bacteria minefield or will it be warm enough to keep the food safe from bacteria?

I can't really stress how important it is to have and use thermometers no matter your experience level. And especially if you are unsure if what you are cooking is safe. I prefer a non electric (less parts, requires no batteries, unlikely to break) meat thermometer.
Comment: I completely agree.  I actually have a thermometer and an infrared temperature gun and they're my two best friends in the kitchen (after my hands).
Answer: According to one of the Rival Crock-Pot manuals, it should not be left on all day. I have no intuition as to why though, other than they offer this advice so consumers don't expect it to bring all foods to a safe temperature.

HOW TO USE YOUR SLOW COOKER

Place the stoneware into the heating base, add your ingredients to the stoneware, and cover with the lid .
Plug in your Crock-Pot® slow cooker and select the temperature setting from the three setting options. Low is recommended for slow
"all-day" cooking. One hour on High is equivalent to approximately 1½
to 2 hours on Low. Refer to your specific recipe for more precise cook
times. Warm is ONLY for keeping already cooked food at the perfect
serving temperature until you are ready to eat. DO NOT cook on the
Warm setting.  NOTE: We do not recommend using the Warm setting for
more than 4 hours.
When cooking is done, unplug your slow cooker and allow it to cool before cleaning.

For more manuals (and recipes and such): Crock-Pot.com Customer Service
Comment: I don't think the 4 hours is a coincidence - it probably produces temperatures in the danger zone (<140F) and so leaving it for longer than that is unsafe.
Answer: Last night I accidentally left dinner on "warm" overnight and when I woke up it was at 147F (still with a fair amount of moisture).  That was with a 6.5qt "SmartPot" model.  Mushy but safe, IMHO.
Comment: Thanks for the info.  We should warn people that they should still check their situation, as It's quite likely that the equilibrium temperature is a function of the crockpot (amount of power it puts into the circuit on 'warm' and the surface area), the ambient air temperature, and the food being cooked (evaporative cooking), and how well the lid's sealed (also affecting evaporative cooling))
Answer:
will it be a bacteria minefield or will it be warm enough to keep the food safe from bacteria

The FSIS (food safety inspection service) has released time-temperature graphs.  At 130F you not only deactivate bacteria like salmonella, you have a 7 log10 reduction in bacteria after 131 minutes (chicken), which is their "safe" limit.
They don't really advertise that you don't have to cook to 165F if you hold the temperature over a period of time.  The USDA public temperatures are the instantaneous meat temperatures.
Answer: @JasonTrue's reply is the answer. Below emphasis is mine:

However, if you reach 145F within the first hour at the highest setting, then keep it at "warm", and test the temperature after about 30 minutes with an instant-read thermometer and it stays around 140-160F, you'll probably be fine.

That first hour is key. You want to get food temp raised out of the low temp danger range as quickly as possible. So high heat for an hour, then low or warm heat for the day.
You might notice many crock pot recipes follow this model.
If you depend on warm to raise the temp, your dish will very slowly raise in temp. That's a risk.
My routine:

wake up, go straight to kitchen and start the dish on high
get ready for work (about an hour)
put the pot on low (or warm), then go to work
Answer: Cheap crock pots that have the Warm-Low-High option don't have temperature sensors or thermostats to reach a specific temperature. The switch controls which of the cooker's heating coils are on.  In my cooker with a three position knob, the settings on are:

Warm
Low
High

75W
175W
250W

small coil
large coil
small+large coil

They do this by energizing either the 75W heater coil, the 175W heater coil, or both together for 75+175=250W.
The actual temperature depends on how the heaters come to equilibrium with the temperature in your kitchen.  If you are concerned about whether "Warm" is above 140°F or not, you should measure the temperature with a thermometer.
If your cooker is below boiling, you can control the temperature by changing the environment around the slow cooker: draping a towel over the slow cooker will trap heat and increase the temperature, circulating air over the slow cooker will remove heat and reduce the temperature.
Answer: here is the latest that I just got from a live chat with CrockPot:
Ashly: On your Crock-Pot, both the low and high settings will reach a maximum temperature of approximately 215 degrees Fahrenheit, but they cycle differently in that the low setting cycles off of that temperature more frequently. Therefore, the High setting will still cook the food in a shorter period of time than the Low setting will. On the warm setting, your Crock-Pot will be between 165 degrees and 175 degrees Fahrenheit. Please remember that these are all approximate temperatures and they can vary depending on what you are cooking. The Crock-Pot can also boil on High and Low. We do recommend that you always fill your slow cooker at least 2/3 - 3/4 of the way full, including at least one cup of liquid or sauce. You may have to adjust your cook times accordingly, especially if you are using older Crock-Pot recipes, or adapting regular recipes for Crock-Pot use. This will prevent the food from drying out and burning.
Comment: Please [edit] your answer and do something about the [wall of text](http://uncyclopedia.wikia.com/wiki/Wall_of_Text). Thanks.
Answer: I have a Hamilton Beach Stay or Go. It boils on low setting. I don't know what the high setting is, except that it is hotter than low. It doesn't boil on warm, so warm is probably 145-160˚F. The best way is to check the meat with an instant digital thermometer. Foods cooked to 180 should be safe for any kind of meat.
Answer: I have the Crock-Pot brand 7 quart manual crock pot. Looking on their website (crock-pot.com) I was able to find the following...
Both the low and high settings will reach a maximum temperature of approximately 215 degrees Fahrenheit, but they cycle differently in that the low setting cycles off of that temperature more frequently. Therefore, the high setting will still cook the food in a shorter period of time than the Low setting will. On the warm setting, your Crock-Pot™ slow cooker will be between 165 degrees and 175 degrees Fahrenheit. Please remember that these are all approximate temperatures and they can vary depending on what you are cooking.
So, if the safe temp for food is between 140 and 165 (depending on meat) then this should keep your food warm enough not to grow any bacteria and probably cook it if left on long enough.


ACRU4: rainfall units for the wetland water balance

Question: Not sure about the rainfall units in the wetland water balance of ACRU.
I have looked at the ACRU4 user manual which comes with the modelling tool installation and a dissertation covering the wetland HRU model structure (Gray, 2011) but didn't see reference to the units. The units are also not mentioned in the drop-down list of variables in the output selector. Please advise?
Answer: In both input and output files, the rainfall is in mm.
Relative to other HRUs, the rainfall depths are the same, but the volumes are different because it depends on the HRU area. For this reason, it is easier to convert the rainfall depth to a volume if you are estimating a water balance.
To convert the depth of rainfall falling on the wetland HRU to a volume, it would be [rainfall depth (mm) / 1000 ] * wetland area (km2)
To work with the rainfall as a depth, the wetland rainfall depth is calculated as an area-weighted value, wetland rainfall depth (mm) = subcatchment rainfall (mm) * [wetland area (km2) / subcatchment area (km2) ]


Application for master's course: should my motivation letter include my contact?

Question: I am applying for a master's program at a german university, and as my whole application includes a CV (with my detailed personal info and contact), should my motivation letter include my contact at the begining? Or is the fact that i am submitting my CV enough for them?
Also, do I include the contact of the university as well?
Comment: The word "contact" is a bit ambiguous here. Do you in all cases just mean information about how to contact you (contact information) or another person who you use as an intermediary (a contact)?
Comment: @Buffy, i mean when you write ur name, e-mail, tel number, address.. at the top left corner
Comment: @Buffy, would you know if I should include the contact of the university as a whole, or of the specific department that I'll be applying for? (currently, i only added the name of the uni, and its adress)
Comment: I'm confused again. My answer assumes you mean information about how they can contact you. That would be your own email, etc. with nothing about their university or department.
Comment: @Buffy, hahaa im sorry for being so confusing. what i meant by the university's contact is: its name, its address, ..
Or maybe should I add the infos of the specific department (name of uni, address of department (each departmet has its own adress) and maybe phone number and email of department)
Comment: I think for the heading of a formal letter, the university and department are probably enough, unless you are addressing it to a specific individual. Then their name and title should be included.
Comment: @Buffy, no email no telephone number, right?
Comment: Doesn't seem to be needed.
Answer: You should probably make it easy to find your contact information by anyone reviewing your application. It is probable, but not necessary, that they will have your complete package, but if they can find the information easily, they will be more likely to contact you rather than delaying it.
So, a certain amount of repetition is called for, I think.


How to complete the quest: Every second counts?

Question: I'm stuck at the Every second counts quest (chapter 2, mission 1). The game wants me to build a deep sea warehouse on the free site of the underwater island. But it says: "you can only have one deep sea warehouse per underwater island" and I don't have any other deep sea warehouses, so I'm pretty much stuck. What to do?
Answer: Just build the deep sea warehouse, to do this you need to put the required materials (8 building modules and 4 tools) on a sub, submerge it and make it move to the underwater island, then the option to build the warehouse appears.
What the game means by

You can only have one deep sea warehouse per underwater island

is that you can only have 1 deep sea warehouse on each underwater island.
Comment: Ahh... The resources are key. I thought the "You can only have one warehouse per island" message was due to an extra warehouse, not a lack or resources! Thanks!


Is it illegal for a parent to watch porn in front of a minor?

Question: We have two computers in my family's office and let's say I'm working on homework on one of them, my dad is almost always on the other computer. My dad always watches gay porn or shirtless male models or things of that sort right in front of me, even though I'm technically facing the other way. Whenever I turn around to see he shifts over to try and tries to cover the screen, but it doesn't work and I can see all of it. He does this pretty much everyday. Is this legal? I'm not even old enough to drive
Comment: What state are you in? Is the "office" at your family home or in an office/commercial building?
Comment: Have you tried asking him to watch it only when you are not around?
Comment: Which jurisdiction are you asking for?
Answer: I disagree with the previous answer, at least as a blanket statement. There are laws in some jurisdictions prohibiting furnishing pornography to a minor. (Missouri.) So it would clearly be illegal (in Missouri) for your father to give you a DVD of porn. Whether routinely leaving porn available for you to watch qualifies as furnishing strikes me as a real question, and there is a case suggesting even one-time display is a crime.
There was a prosecution of a substitute teacher who turned on the classroom computer and porn came up. The case was a travesty, and the real problem were the school's incompetent IT people, who didn't run up-to-date antivirus software on the computers, as a result of which it had suffered a browser hijack. The teacher was originally convicted, reversed on appeal when they got some tech-savvy attorneys.
Answer: I believe it is a capital crime in Saudia Arabia: you need to me a bit more specific about jurisdiction. In the US it is not a crime, and First Amendment considerations would make it difficult for there to be such a law. That does not mean that there are no possible civil sanctions that could be imposed. Courts have broader leeway to intervene on behalf of the child even though parents have great constitutional liberty to control the upbringing of their children, and if a child is cruelly mistreated, those parental right can be terminated. But the court (judge) does not have an unlimited right to arbitrarily decide that it is child abuse to make a child go to church, or not go to church, or watch porn, or not watch porn. Each state will have laws pertaining to "child abuse", e.g. RCW 26.44.020 for Washington, defining it in terms of sexual exploitation or injury that causes harm to the child's health, welfare, or safety; or negligent treatment; or similar expressions.
The simple act of viewing porn when a child is present and might accidentally see it would not be actionable in terms of child abuse laws, but if it is part of a broader pattern of sexual behavior with respect to the child, it could indeed constitute abuse. Under the innocent interpretation of carelessness, if a complaint were filed, a social worker might give the parent a mild talking-to, but this would not likely lead to any civil (or criminal) action.
Comment: Does it make any difference if the person watching porn is not the parent of the child?
Comment: I would also point out that films in the United States that are Rated R (and to a lesser extent, PG-13) will allow those below the age restriction to take children into a film as accompanied minors.  These films are allowed certain extent of on screen nudity and neither the theater nor the parents/guardians are arrested for bringing the minor.


Mounting iPad/iPhone on Ubuntu 12.04

Question: Is there an update on the issue about mounting IOS devices on Ubuntu that has the "trust this computer" message loop?
Comment: I'm able to mount my devices in 14.04
Answer: The issue was resolved after updating my 12.04 to 14.04. It might not be the best answer but it resolved the issue. I just hope there is an easier way to resolve this.
Answer: There are updated packages available in a PPA that might help with your problem. To install them, do the following.
<code>$ sudo apt-add-repository ppa:ingo/ios7support
$ sudo apt-get update
$ sudo apt-get upgrade
$ sudo mkdir /var/lib/lockdown
$ sudo chmod 777 /var/lib/lockdown
</code>
Comment: I did the steps given but still unable to mount my iPad. I got a message box that says Unable to mount iPad - DBus error org.freedesktop.DBus.Error.NoReply: Message did not receive a reply (timeout by message bus).

Mounting iPad/iPhone on Ubuntu 12.04


A simple "number of bit strings", so I thought

Question: How many bit strings of length 10 contain at least three 1s and at least three 0s?
Answer: Let's think about just placing the 0's and let the 1's fill in the remaining spots. The cases we are interested in are how to get exactly 3, 4, 5, 6, and 7 0's.
How many strings have exactly 3 0's? This is just the number of ways to choose 3 locations out of 10 available locations where order doesn't matter, which is $\binom{10}{3}$. Remember, we're only focusing on the 0's - the 1's just fill in the remaining spots.
The argument is the same for getting exactly 4, 5, 6, and 7 0's. To get the total, we just add them all up:
$$
\binom{10}{3} + \binom{10}{4} + \binom{10}{5} + \binom{10}{6} + \binom{10}{7}.
$$
Comment: Your answer totally makes sense. Now I know why I was undercounting in my attempt. It seems for the at-least type of questions, a good approach to solve them is to use a systematic method as exemplified by yours to ensure correctness. Rushing to solve by a shortcut, especially in a test, probably will result in an incorrect answer. Thank you a bunch.
Answer: Consider the complementary problem: at most 2 0s or at most 2 1s. The counts for each case is $\binom{10}{2}+\binom{10}{1}+\binom{10}{0}=56$; the count for at least 3 0s and at least 3 1s is therefore $2^{10}-2\cdot 56=912$
Answer: As we will have 10 places total so this problem will get reduced to 10 places consisting of 7 zeros and 3 ones ,6ones and 4 zeroes, 5 ones and 5 zeroes.  so
$(2\cdot\frac{10!}{7!\cdot 3!})$   (one for 7 zeroes and 3 ones and other case is 3 ones and 7 zeroes)+$2\cdot \frac{(10!}{6!\cdot4!})$  (one case 6 ones and 4 zeroes and other vice versa)+ $\frac{10!}{5!\cdot 5!}$
so Total answer is 912
Answer: Hint: The number of $0$s is between (this) and (that); how many strings of length $n$ contain exactly $k$ zeroes?


How do I edit files in network locations in Windows 10?

Question: I added a network location in Windows 10 as FTP (something like this tutorial: Setup an FTP disk in Windows Vista and 7. I can access all the files, but I can't edit them like other files in other hard drives. How can I edit files in this network location?
Comment: Please don't post in all-caps, that's considered shouting. It's been edited for you, but please keep this in mind the next time you post.
Answer: FTP protocol does not support editing files. The files will have to be transfered, edited and transfered back when done.


Audio Activity Detection and Classification

Question: I am starting a new project. Actually, my real intention is to learn speech recognition but for warming up I want to improve in audio signal processing.
In my project, I aim to record sounds except for human speech in my house when I go out. I am planning to divide my project two sections: Audio Activity Detection and Audio Classification. However, some questions appear in my mind.
What is the best techniques for audio classification? Could you supply some informative articles for me? I saw that MFCC and CNN are generally used for speech recognition. They are also valid for audio classification? Or, should I seek another methods? My classification includes baby cry, door knocks, door opening, door bell, ringing home phone, smoke detector etc. Even though their frequencies, in contrast to frequency of human speech, cannot be limited in a specific range, should I study on frequency for classification?
When I say Audio Detection Activity, I imply that sound recording starts if silence is broken, i.e. there is a sound. For preprocessing, I will filter out the noises. Therefore, noise will be part of the silence.:)  I searched few articles and I encountered the topic of Voice Activity Detection (VAD) but it is used to understand whether human speech is present or not in the environment. I am not interested in voices. Instead, I want to collect sounds mentioned before. Is Audio Detection Activity a valid term?
I am waiting for your advices and sources.
Thank you.
Answer: Here is an recent introduction video on the subject (2019): Audio Classification with Machine Learning


How to reliably tell which maven plugin fails a Jenkins build?

Question: So in Jenkins I'm using a variety of useful plugins like Cobertura, Emma etc, all of which are likely to fail for various reasons.
In general these plugins have terrible error reporting so it's often not possible to easily tell which plugin failed the build. Usually all I'll see is a subsequent message from another plugin saying it's not going to do anything because the build had been previously marked as FAILED by some other plugin, but there's often no indication of who that other plugin is.
Is there a way to get maven to actually identify which plugin failed a build, when the plugins themselves fail to do so?
Answer: You can turn on Maven debug output using -X flag with mvn command and -e flag to enable full execution error messages.


Magento2 Braintree not showing on checkout when in Dev, Live and Test servers using either sandbox or production mode

Question: We have setup a Braintree payment method and its working ok when on local but when we tried to setup it in our dev, test and live sites the Braintree is not showing on checkout page using either sandbox or production mode. Does anyone have the same issue and solved it? Thanks.
Answer: Please check you have entered proper data like.
merchant account id:
merchant id:
publickey:
private key:
Because in magento2 that field sequence is changed.And check currency because braintree require different "merchant account id" for different type of currency.


wp_insert_post with data from graph api inside a plugin

Question: I'm creating a plugin that creates a post in a CPT for every Facebook page post (using fb graph api). When should I fire the function that gets the data? using an action? Also if I understood the docs correctly, the wp_insert_post takes ID as an argument, which if doesn't exist, sets the newly created post id to that value?
Answer: There's no way to get notifications from Facebook for a new post. You have to check by hand. Just set a transient with the desired expire time for the data so you don't make a request on each reload, maybe check hourly for new data or every 30 mins, up to you.
As for your second question, read the docs:
https://developer.wordpress.org/reference/functions/wp_insert_post/
It automatically assigns an ID unless provided by you (which is auto-incremented by the system) but you still need to provide more things in the array, even if some are default, you might not want it like that.
Comment: Thanks for replying. Good idea to set an expire time, coz for now I just set it to plugins_loaded action. About the ID, I miss-understood, just setting a value to ID doesnt set the ID (if not already set), apparently I can use 'import_id' instead.. still working on it coz it hasn't worked till now.
Comment: @SilvesterVella I mean, that's just how transients work. I'd honestly say not to touch the ID. Unless you have a very good reason for having a custom one (which, if you do, let me tell you, you're probably wrong), it messes up the internal auto-increment in the database, say you have a post with ID 352, but you suddenly decide to insert a post with ID 300, which doesn't yet exist, so it's valid, what will happen is that now your auto-increment is reset to 300 in the database, **if I remember correctly.**.
Comment: Thanks a lot for that info. To be honest, the idea was so that it won't create duplicate posts, so I figured if the ID exists (which was going to the date/time of the facebook post created) it will update that post, if not, create a new. Given what you said, better if I just check the post title or slug or someting.
Comment: @SilvesterVella Duplicates can never, ever happen in WordPress in terms of ID, but if you reset the auto-increment, your post "logic" might not make sense at some point, as in "why the hell does this have this ID but it was posted before this post with a higher ID?"
Comment: True. When I said duplicate posts, I meant because the plugin will create posts for every facebook post. So every time it gets the json data, it will create posts with the exact content. But if I just check the date or something before, shouldn't be a problem. I was complicating things for a minute there.


How to have multiple archive pages?

Question: I am building a site that needs pages such as News, Events, Projects and People. My question is, how should I achieve this in WordPress? Do I use custom post types? And if so, how do I have a page for each?
Answer: You can also use categories as News, Projects etc. and use category archive page as the archive for them. But this will limit the functionality as you can not easily categorize the posts within that category. So I recommend using cusom post type for that.
If you decide to go with custom post type then you'll need to set the has_archive parameter to true While registering post_type, That will enable archive page for that post type, It uses $post_type as slug for archive page for that custom post type, then archive page url will be
mysite.com/post_type/
Comment: That's helpful, distinguishing the use of categories from custom post types - thank you for clearing that up for me. I created a custom post type, with `has_archive` set to true, but going to `/post_type_slug` isn't doing anything.
Comment: does it giving 404 error ?
Comment: No, it takes me to my home page.
Comment: this sort of work but I cannot access to `mysite.com/post_type/2012/02` for examples. Moreover the links of widget archive always point to thinks like `mysite.com/2012/02`...

How to have multiple archive pages?


Can choke on a motorcycle compensate for dirty carbs without causing fouling?

Question: My 92 Katana 600 dies on idle with the choke off, no matter how warm the engine.  I've found that leaving it on 1/2 - 3/4 choke gives it a good balance.  I know that choke can cause fouling and carbon deposits if you use it too much, but my thought is dirty carbs run lean and choke can richen it up to a normal mixture.  Is this flawed logic?
Comment: clean the carbs, make sure the jets are clean then adjust the mixture and idle speed to within correct limits. Oh and make sure the air filter is clean...
Comment: A clogged air filter would be more likely to help in this situation as it would richen the mixture @SolarMike, but all good advice in general.
Comment: @GdD So, back to treat the symptom or the cause...
Comment: Totally @SolarMike, carb cleaner is your friend, maybe a can of seafoam as well.
Answer: No, a choke cannot compensate for dirty carbs because you'll never get full power out of your motorcycle if you run on it. Here's a picture of a carb:

When you pull the choke it closes the choke butterfly valve or a choke plate, reducing the airflow and richening the mixture. That means no matter how much the throttle valve opens you will not get full airflow, so you won't get full revs. It's not a good idea, I'd only do it to get to a place I could get things fixed.
If your engine is dying on idle you need to resolve the problem. It's probably pretty simple, it could be dirty carbs, it could be a clogged fuel filter, your best bet is a can of carb cleaner and a bit of time. Be sure to use it in a well ventilated area!
Comment: on some bikes the "choke" is actually an enrichment circuit with a second fuel tube controlled by a valve, which is actuated by the choke lever/plunger/solenoid-- in these cases this wouldn't hold exactly true
Comment: For sure @Ceshion, I'm assuming manual choke as its implied by the OP
Answer: You can roughly compensate with the choke for a shortage of fuel, but you can't properly control your choke to compensate the exact right amount while driving, so your bike will run terrible if you try to.
Furthermore, if your choke is one in the literal form, so that it restricts the inlet flow, it will also (heavily) limit your power as already mentioned by others. An engaged choke that is properly tuned, enriches the mixture the right amount only AT IDLE. It will become way too rich if you use the same setting while driving. The fuel metering and ignition advance will be off.
So i'd strongly advise you to pull open your carb and clean it. Often, the float chamber is full of rust powder and dirt. Check the fuel lines and filters for blockings/restrictions and dirt and make sure fuel from the tank can freely reach your carbs. While you're busy, i'd also recommend checking your sparkplugs and exhaust for sooth deposits.


after installing Ubuntu 16.04.1 LTS from a bootable drive I can't get the system to run without the pen drive

Question: I have a fresh laptop with a clean hard drive. I made a bootable pen drive of Ubuntu 16.04.1 LTS and booted it to the computer.  I then Installed using the install wizard on the system.  it completed and asked me to restart, I restarted and everything worked wonderfully. I shut the laptop down removed the pen drive and rebooted and it said no bootable operating system was found. But when I put the pen drive back in the system started up fine.  I am pretty novice and have had difficulty following some of the other solutions to this problem.  I did make sure that my system was set to boot from the hard drive in BIOS but that all I have really done.  Can anyone take the time to explain the process of using the terminal to program the system to boot from the hard drive like it should? I used the partitioning program when installing so it created a partition for the booting and flagged it as booting.  I just need to know what code to run through to get to the solution.  Any help would be appreciated
Comment: Can you run sudo update-grub and see if that fixes things?  Check the /sys/firmware directory, if an efivars directory exists, you are in UEFI mode, in that case, did you install to the hard disk in UEFI mode?
Comment: How would I run sudo update grub?
Comment: Open a terminal window by pressing ctrl-alt-t.  Then type `sudo update-grub` The system will prompt you for a password, type it in.  Nothing will show while you type, the cursor will not move. Then hit enter.  Then the command will run and some output will appear in the terminal window.  When it has finished, power off the system, remove the USB, and power it on.
Comment: /usr/sbin/grub-probe: error: failed to get canonical path of `/cow'.
Comment: I got this error
Answer: The problem is almost certainly that your GRUB installation is split across both disks -- the GRUB binary itself resides on your hard disk (either on the EFI System Partition [ESP] if the computer boots in EFI/UEFI mode or in the MBR and post-MBR sectors if the computer boots in BIOS/CSM/legacy mode), but because your main installation is on the USB flash drive, the GRUB configuration file and some other critical files reside there.
If I'm right, there are, broadly speaking, at least three ways to fix this problem:

Move GRUB entirely to the hard disk -- To do this, you should create a /boot partition on your hard disk. Such a partition can be fairly small (~500MB is likely to be enough). You'd need to adjust /etc/fstab to mount this partition automatically, move the current /boot directory's contents to the new partition, and re-install GRUB. The trouble with this approach is that your USB drive will no longer be portable; it will work only on the computer on which you install the system.
Move GRUB entirely to the USB drive -- You can move GRUB so that it resides entirely on the USB drive. Once done, you may need to use the computer's built-in boot manager to select which OS to boot. Details of how to do this depend on whether your system uses BIOS-mode or EFI-mode booting:

BIOS -- In BIOS mode, simply doing a sudo grub-install /dev/sdb (or whatever the USB device is) will re-install GRUB; however, you must then restore the MBR of /dev/sda (or whatever the hard disk is) so that it holds the Windows boot loader. This is basically a Windows task.
EFI -- In EFI mode, you must ensure that the USB flash drive has an ESP, then reconfigure /etc/fstab so that the USB drive's ESP is mounted instead of the hard disk's ESP and re-install GRUB with sudo grub-install. You may also need to delete the EFI/ubuntu directory from the hard disk and/or adjust EFI boot options using the efibootmgr utility.

Abandon GRUB -- Most boot loaders don't spread their configuration files across disks the way GRUB does, and so are likely to work better. Details vary depending on what boot loader you use, though. For EFI, my page on the subject covers available options. I don't know of a page that succinctly summarizes BIOS options, though. In either event, you'd need to install the new boot loader using whatever procedures it requires, and possibly clean up the old GRUB installation in some way. You may also need to re-install the Windows boot loader in some cases.

There are some other hybrid or more exotic options, but I'll leave it at these since they're the most practical and broadly applicable.


Is a bone marrow transplant limited by sex?

Question: Can a female patient get transplanted with bone marrow of a male donor and vice versa?
Comment: Well, I guess it's possible because graft rejection/acceptance is based on MHC/hla which are not dependent on sex.
Answer: Short answer: Yes. Because in almost all cases of organ transplant, the organ recipient will be administered immunosuppressive drugs.
There is some literature on the effect of sex on the outcomes. I have included two hints here.
from: http://www.nature.com/bmt/journal/v35/n6/full/1704861a.html
The impact of the donor gender on outcome in HLA-identical sibling donor hematopoietic stem cell transplantation for multiple myeloma was studied in a retrospective registry study of 1312 patients (476 male to male (M → M); 334 female to male (F → M); 258 male to female (M → F); 244 female to female (F → F) reported to the European Group for Blood and Marrow Transplantation (EBMT). The best overall survival (OS) from the time of transplantation was found in F → F (median 41 months) with no significant difference between other groups (median 25 months in M → M, 18 months in F → M, 19 months in M → F) despite a significantly higher nonrelapse mortality in F → M. This was due to a significantly lower relapse rate (REL) in F → M compared to all other groups. Before 1994, OS was poorer in F → M than in M → M, which improved to similarity from 1994 onwards (median 29 months in M → M and 25 months in F → M). The reduced REL contributed to this improvement in F → M indicting a sex-specific graft vs myeloma effect. Therefore, a female donor is as good as a male one for male patients, while for female patients gender disparity is a negative factor for outcome.
from: https://www.broadinstitute.org/news/1386
"It's been clear for some time that bone marrow transplants involving a female donor and a male patient pose a higher risk of GVHD," said Bradner. "This 'sex mismatch' arises from genes that are carried on the male-specific Y chromosome and are therefore present in males but not in females..."
Answer: Anyone can be a donor ir recipient in hla markers are same or a close match. A female donor over 45 who has had 2 or more kids is the worst donor choice. This is because when a woman is pregnant the blood cells get good at attacking foreign blood from the baby. When the blood is given to the recipient there will be higher likelihood of gvh bc the blood will attack the host. By bone marrow, it's really stem cells, baby blood cells. Once transplanted they replicate and are the new blood and immune system. My donor was my brother. 15+ years ago.
Comment: Thank you for your contribution.  It could be improved by adding a reference to a source for the donor pregnancy-history effect.


How to romanize velarization, palatalization, and labialization?

Question: I started a conlang inspired by Marshallese and Navajo, and have taken several labialized, palatalized, and velarized consonants from them. However, I am unsure how to romanize these consonants.
Answer: You have three main options here:

Use new letters for each one. Latin does this, with C /k/ vs Q /kʷ/. This will get infeasible if you have a lot of them.
Have diacritics for palatalization, labialization, and velarization. This is common in Eastern European languages that use the Latin alphabet, contrasting T D N vs Ť Ď Ň and so on. The downside to this method is that they can get difficult to stack, if you can have e.g. a palatalized labialized stop.
Have separate letters that mean "palatalized", "labialized", and "velarized". Most modern forms of Cyrillic do this, with the letters Ь and Ъ indicating whether the preceding consonant is palatalized or not. IPA also does this: tʲ, tʷ, tˠ.

Which one you choose mostly comes down to your sense of aesthetics, and how you expect the language to be written/typed.
Comment: listing Cyrillic solely in the third category seems odd to me, seeing as East Slavic (which is what most people not specifically knowledgable about e.g. the languages of the Northern Caucaus, Central Asia, or historical languages tend to think of as the prototypical form of Cyrillic) is arguably more like the first option, but with the different letters being those for the following vowels (with the yer's only being used word-finally or before a palatalising vowel for /ʲj/ or /ˠj/ respectively)
Comment: 1. I am not sure if infeasible is the right word because I have eight separate distinguishing pairs, but the other two seem more elegant.
2. Seems like something I can do, especially since I am handwriting everything in a notebook rather than typing it onto a spreadsheet.
3. Again seems attainable. In fact, I have in this short time been distinguishing palatalization with a j digraph because I do not have j in my romanization. Unsure what to do with labialization though.
I am torn between options 3 and 2.
Answer: In addition to the methods given by others, you could also try the Irish approach (which has similarities to the Cyrillic systems): divide your usual vowel letters into sets for each coarticulation, then only allow vowel letters that match the consonant's coarticulation to be written adjacent to it.
This works perfectly nicely when you have palatalising vowels before and after palatal consonants, but when you don't you end up needing to insert additional vowel letters that are not present as distinct vowel phonemes in order to ensure that no vowel is next to a consonant it doesn't match coarticulation with.
This is why the Irish form of the name Mary, Máire has an , despite being pronounced with an /ɑ:/ or /a:/ in the first syllable (depending on dialect). The r is soft (palatalised) and so cannot appear next to the <á>, and so an  is inserted.
This process is also one major factor that can make Irish vowels difficult to predict from the spelling (even within a given dialect), as it's not always clear which of the vowel letters are phonemically present, and which are just there to mark coarticulation of the consonants.
Depending on your goals that could be either an advantage or a disadvantage.
Answer: Here's another option:
If basically every consonant has a palatalized (resp. labialized, velarized) form, consider transforming the following vowel letter instead of the consonant letter itself. This is what Cyrillic does, in addition to the "hard" and "soft" signs that Draconis mentioned. It has ten vowel letters, five "hard" (un-palatalizing) and five "soft" (palatalizing). It's a bit more complicated than that, since the Slavic languages have evolved considerably since the Cyrillic alphabet was invented to accommodate them. Case in point: the letter I only appear in digraphs now, to the point that those digraphs are in the alphabet, but I itself is not.
Answer: If you have a separate -ized form for each one, digraphs are probably your best bet. Depending on what other sounds you have and how you romanize them, you could use j, w, and x (i.e. tʲ tʷ tˠ are tj tw tx). But of course, it's up to you.
Another way you could do it (this is Mark Rosenfelder-style) would be to use the IPA characters themselves (i.e. tʲ tʷ tˠ are tʲ tʷ tˠ). This is another aesthetic, and works really well if that's the aesthetic you're going for. I find it gives exotic vibes. But it comes down to personal preference overall.


J1 to F1 after a gap- am I non resident?

Question: I was on J1 (research scholar) visa in 2009 and 2010. Then I stayed out of US and came back on F1 student visa in 2015 and held the F-1 student visa for 2015, 2016, 2017, 2018, 2019. My question is for the 2019 tax year, am I a resident alien or non-resident alien?
Answer: You were an "exempt individual" (exempt from the Substantial Presence Test) as a "teacher or intern" (which includes any J1 who is not a student) for your time on J1 in 2009 or 2010, since for neither year were you an exempt individual for some part of 2 of the previous 6 calendar years.
You were an "exempt individual" as a student for your time on F1 as long as you have not been an exempt individual of some part of 5 previous calendar years. So you would be an exempt individual for your time on F1 in 2015, 2016, and 2017. For 2018 and 2019, you would not be an exempt individual for any part of the time you were on F1, because you had already been an exempt individual for some part of 5 previous calendar years (2009, 2010, 2015, 2016, and 2017). So all your days of presence in the US in 2018 and 2019 are counted in the Substantial Presence Test, and (assuming you were in the US for most of the year), you are a "resident alien" for tax purposes for 2018 and 2019.


Time based workflow queue

Question: Currently i am sending notification to owner and manager of lead after 5 days from lead creation based on few user profiles rule criteria in workflow.
Now i need to send notificatios only  when status on open so added the condition in workflow rule criteria.
Please let me know what about the notifications which are already in queue
Let me know how to test this time based workflow
Comment: Records in the time-based workflow queue are not affected unless the underlying records are modified by DML (update/delete) and such DML causes the workflow rule to remove the record from its current place in the time-based position. This is covered in the [doc](https://help.salesforce.com/HTViewSolution?id=000005245)
Answer: If you go into setup, you can find the time-based workflow rule queue located under monitoring. This feature lets you search for time based rules currently scheduled based on criteria like:

Scheduled date
Created date
Rule name
Object
Etc

You can go there to find any time based workflow rules still scheduled. You may also delete them if desired.

Time based workflow queue


Does Rust have a dlopen equivalent

Question: Does Rust have a way to make a program pluggable. In C the plugins I create are .so files that I load with dlopen. Does Rust provide a native way of doing the same thing?
Answer: The Rust FAQ officially endorses libloading. Beyond that, there are three different options I know of:

Use the shared_library crate
Use the dylib crate.
Use  std::dynamic_lib, which is deprecated since Rust 1.5. (These docs are no longer available in version 1.32; it's likely the feature has been dropped altogether by now.)

I haven't tried any of these, so I cannot really say which is best or what the pros/cons are for the different variants. I'd strongly advise against using std::dynamic_lib at least, given that it's deprecated and will likely be made private at some point in the future.
Comment: Yeah, libloading appears to be the sanctioned way of doing this now.
Answer: Exactly,
And below is the complete use case example:
use std::unstable::dynamic_lib::DynamicLibrary;
use std::os;

fn load_cuda_library()
{

    let path = Path::new("/usr/lib/libcuda.so");

    // Make sure the path contains a / or the linker will search for it.
    let path = os::make_absolute(&path);

    let lib = match DynamicLibrary::open(Some(&path)) {
        Ok(lib) => lib,
        Err(error) => fail!("Could not load the library: {}", error)
    };

    // load cuinit symbol

    let cuInit: extern fn(u32) -> u32 = unsafe {
        match lib.symbol("cuInit") {
            Err(error) => fail!("Could not load function cuInit: {}", error),
            Ok(cuInit) => cuInit
        }
    };

    let argument = 0;
    let expected_result = 0;
    let result = cuInit(argument);

    if result != expected_result {
        fail!("cuInit({:?}) != {:?} but equaled {:?}",
                argument, expected_result, result)
    }
}

fn main()
{
    load_cuda_library();
}

Comment: For the recors, issue #458 has been closed, the new one is https://github.com/rust-lang/rust/issues/15040
Comment: You are quite right. Any library that is C compatible can be loaded. Unfortunately it breaks the safety. However the scheme above is subject to change. The Rust developers are going to add a safe way for  dynamic loading of libraries, see https://github.com/mozilla/rust/issues/458
Comment: I assume this loads any library that is C compatible? And I would assume that loading the symbol like with dlopen doesn't actually know the function signature which means that you can't be really sure you are calling the function with the correct arguments. This would seem to break the safety that Rust gives you but I guess loading other code at will is not necessarily the safest thing to do in the first place.
Comment: Has been moved again (since it didn't make it to the 1.0 version of Rust): https://github.com/rust-lang/rfcs/issues/661
Comment: I don't think this should be the approved answer @Matt, it suggests the usage of unstable, not-easily-accessible functionality in Rust. The Rust FAQ gives a different suggestion than this (see my answer to this question for more detials).
Answer: Yes. There's a module std::unstable::dynamic_lib that enables dynamic loading of libraries. It's undocumented, though, as it's a highly experimental API (everything in std::unstable is undocumented). As @dbaupp suggests, the source is the best documentation (current version is af9368452).
Comment: ([The source](https://github.com/mozilla/rust/blob/af9368452d8578af219713b34f7e3be4bd085186/src/libstd/unstable/dynamic_lib.rs) is the best documentation.)

Does Rust have a dlopen equivalent


What to do when scholars are divided on an opinion?

Question: I wanted to know what to do when scholars are divided on an opinion? Sometimes whenever I search whether a thing is halal or haram, scholars are divided on the opinion, some say it's halal, some say it's makrooh and some says it's haram, so what should we do in this situation? Should we go with the choice which is most suitable for us? And will that person be punished if an action was haram to do
Comment: see also : https://islam.stackexchange.com/questions/74471/etiquettes-of-reading-tafsir/74506#74506. I do not think that your question is duplicate to that one; good question +1
Answer: It is necessary to mention a few points: 1. Usually and naturally in the theoretical issues of any field, the experts and scientists of that field disagree with each other on a series of issues, including ijtihad in the rules of religion. 2. The authorities do not differ from each other in all matters of religion. The difference of authority is in some details of the sub-sentences; Because in the doctrinal principles, generalities and general principles, the sub-rules such as the principle of prayer, fasting, Hajj ... and in many partial rules agree and do not differ. Due to the importance of ijtihad, which is the survival and continuity of the religion, Islam has ignored some of its minor effects, namely the occurrence of differences in some cases.
In such cases, it is better to follow a religious scholar who is scientifically superior. But if the action seems difficult for you according to that  scholar, you can follow the opinion of another  scholar so that you do not suffer.
https://www.makarem.ir/ahkam/fa/home/istifta/269705/%d9%88%d8%b8%d9%8a%d9%81%d9%87-%d9%85%d9%82%d9%84%d8%af-%d8%af%d8%b1-%d9%85%d8%b3%d8%a7%d9%8a%d9%84-%d8%a7%d8%ae%d8%aa%d9%84%d8%a7%d9%81%d9%8a
https://www.islamquest.net/fa/archive/fa3514


how to enable automatic login in windows 8

Question: I have disabled my windows 8 lock screen but i would like to disable logging in altogether so that windows 8 automatically logs me in. If it is possible to disable lock screen, see here, then i'm sure there has to be a way of disabling logging in altogether but i don't just know how to. Can anyone help?
Comment: Also see [here](http://superuser.com/questions/472553/how-do-i-prevent-the-welcome-screen-lock-screen-from-appearing-after-idling-in) for lock screen disabling and enabling auto login.
Comment: @aditya if you feel that a question is a duplicate of another please use the flagging option instead. This will alert higher rep users and they can decide upon the action to take.
Comment: its not a duplicate. That question handles disabling the lock screen. I have disabled my pc lock screen. I even put a link on how to that in the question.
Answer: Press Win + R and enter:
netplwiz

Uncheck the Users must enter a user name and password to use this computer check box and then hit apply.

This will bring up a dialog which will ask for your password, enter it and hit OK.

When you restart your PC next, you should be automatically logged in.
Comment: that's easier than typing "control userpasswords2"!
Comment: I wonder if having a Microsoft account changes anything. These are the same usernames, but one is local: http://i.stack.imgur.com/ywMEa.png
Answer: Start the User Accounts settings by running netplwiz (Win + R). Uncheck the box

Users must enter a user name and password to use this computer

More information
Comment: I press start and type run
Comment: Should be, "from the start screen type "run"
Comment: Changed back to `Win + R`
Answer: On a related note if you need to enable auto logon on windows server - you need to set the following registry values. (This answer assumes that you are aware of the security concerns with enabling the auto logon on a server and still want to do it.)
Under HKLM\software\Microsoft\Windows NT\CurrentVersion\winLogon key, set following reg values (all REG_SZ)
 1. AutoAdminLogon 1
 2. DefaultUserName
 3. DefaultPassword
 4. DefaultDomainName (for workground - I see this getting set to machine name)
restart the server. You can refer details here. While link is for win2k server but it seems to be applicable to winserver 2012 also.
Comment: This is not an answer to the question, it is the answer to a different question.  The appropriate way to provide this information is to write a new question, which you answer yourself (that Q&A format is fine on this site).


Issue with Smooth Shading with Array?

Question:
So I've go a mesh more or less the shape of a slice of bread. I've added an array modifier and curve modifier, and connected it to said-curve to get what you see here. My issue is that when rendered after being shaded smooth, it gets that weird jagged shading issue on the side of it. Each line is where one piece connects to the next in the array. Whether I apply the array, its still there, whether I merge by distance after changes nothing, and I'm getting a headache trying to figure out what is going on. Any recommendations?
Comment: Internal faces? Do the slices have open faces?
Comment: Can you show us a bit more (for example the object that gets the array, screenshot of modifiers, ...) ? Maybe your array is too big and you have multiple roundtrip ?
Comment: hello please share your file (the object itself): https://blend-exchange.com/
Comment: I've added photos for the modifiers, the object I'm array-ing, as well as the shape I'm going for in order to show that it isn't looping in on itself. I also added the file link as requested.
Answer: Like @robin-betts mentioned, there are internal faces inside the "Bread-Wall" which mess up the shading. Deleting the front and rear face of the original mesh fixes that issue.
A better way of doing this would be to remove everything but a single outline of the bread mesh, convert it to a curve (Object -> Convert) and to assign it as a "Bevel" object for your curve.
This way you

Can fill the caps by using the checkbox instead of manually filling them
Can adjust the "slicing rate" without being limited by the mesh width

On the other hand, if you want to go for individual slices, your current approach is already the right solution - you just need to disable the "merge" option of the array and bevel the edges of the bread mesh to give it some definition.

Issue with Smooth Shading with Array?


posttype and custom fields on multisite

Question: is there a plugin to create custom post types and custom fields on the main network itself so that its available across all the sites in that network and can be accessed by all sites in that networks...for single site we use advanced custom field and simple post type is there anything for multi-site too? plz don't say Multisite Post Duplicator as it creates a copy of the post type custom fields etc for each site in the network...that way the database would become too huge with multiple copies.
Comment: Note that databases can handle millions of entries, the problem with large databases is not so much that they're large, but that people write themes with awful queries, asking for things that are expensive to query for, e.g. show me everything except X Y and Z, or show me all posts with a post meta equal to A B or C
Comment: This can be done. But first thing first, `all sites on WordPress multisite do not share any post types table`. So what you can do is create the table/logic on the main site, then use filters and actions to extend the contents to other sites.

So for example, to display the post type on other sites, you can check once the post view screen is active on the admin, so instead of fetching on site-specific tables, you fetch directly from the table and vice versa.

So on other sites just fetch and apply whatever actions you want, but you only have one table which is located on the main site.
Answer: All websites in the multisite are independent and have own database tables, and they can have own plugins and own post types. Post types need to be registered on each site in the multisite, and posts have to be in the database tables for each site. There is no content on the network level that all sites can share directly.

posttype and custom fields on multisite


Is there an interactive firewall for outbound traffic on Ubuntu?

Question: I wish to prevent some programs from "phoning home", and to allow other programs to access only specific web servers.
Is there any way to interactively allow or decline outbound communication from individual programs on Ubuntu?
Comment: [This question](https://unix.stackexchange.com/questions/560965) on the Unix StackExchange suggests some interactive programs, such as OpenSnitch and Douane. I think that's the sort of thing you are looking for (were looking for 12 years ago!)
Answer: That would be netfilter/ipfilter with some script that would do things interactively (maybe with the nice API available on Ubuntu) using a background scripting.
There is some old discussion at this UbuntuForums page.
Also see, Ubuntu IPTablesHowTo and Firewall pages.
Answer: You could give Anoubis a try. There are installation instructions and packages for Karmic Koala available (I'm new to superuser, so you'll have to find them yourself >:-S Hint: on the Download page scroll down to "Distributions").
Answer: Well not exactly interactive but I know about 3 ways to restrict network access to programs.

By default linux assigns permissions to users and every program they run has the same permissions. Run the untrusted program as a separate user. This is pretty simple if you can do it. (Sometimes you can't like when a program requres root privileges.) Add the following firewall rule:
iptables -A OUTPUT -m owner --uid-owner ${untrusted_uid} -j DROP

If you are not afraid of patching the kernel try grsecurity. It allows different permissions for different executables for the same user. This is probably the best way because you can integrate it with iptables rules and specify detailed restrictions. The rules should look something like:
...
role your_regular_user u
    ...
    subject /path/to/untrusted/program
        connect disabled
    ...
...

Disable the connect() function with LD_PRELOAD. This is the ugliest way only use it if you have no other option. You will need a library like this:
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>

int connect(int sockfd, struct sockaddr const* addr, socklen_t addrlen) {
    errno = ECONNREFUSED;
    printf("connection refused\n");
    return -1;
}

Compile this with
gcc -fPIC -shared -Wl,-soname,fake_connect fake_connect.c -o libfake_connect.so

Start the program with
LD_PRELOAD="./libfake_connect.so" ./untrusted_program

Answer: I had been using gufw for some time, it's nice and easy to install/configure. gufw doesn't come with Ubuntu installations. You have to install it manually 'sudo apt-get install gufw'.
Here are some of the references.
https://help.ubuntu.com/community/Gufw


Nameserver config: local or external IP

Question: I'm setting up a BIND nameserver on my Linux server computer. Now if BIND asks me for a IP address for a A Record, should i enter my local ip (192.168.178.21) or my external ip (188.8.131.52)? All webservers etc. run in the same network as the nameserver (even the same computer).
Answer: Give it the address for the interface you want the other computers to use. If you want them coming in on the 192 interface, give it that address.
Answer: If the only hosts needing to resolve DNS are on your local network, then you would use your private IP address (192.168.x.x). This is commonly used for company intranets, so you can have a site setup like hxxp://email/ or hxxp://helpdesk/
If you would like the general public to be able to resolve your domain (foo.com) to the IP address of your webserver, then you will have to bind the nameserver to your public address. (80.x.x.x)
This of course is assuming your public facing interface has no firewall rules preventing traffic. If you are sitting behind certain types of devices (NAT), then you would be able to use a pivate IP address (192.168.x.x). Without any more information, I am going to assume you NEED to use your public IP (80.x.x.x) in order for someone across the country to use it.
Comment: No. If you want the public to be able to resolve your domain name using your nameservers, then you need to bind the service to your public IP (22.214.171.124) and make sure there are no firewall rules preventing incoming connections.
Comment: If you are running a DNS server that ONLY local machines will use. (i.e: small company intranet wants to create a faux domain http://my.website/ then you would use the private IP (192.168.x.x)
Comment: Sometimes you need to do both. In this case you either run two servers (one internal, one external) with the internal server deferring to the external server when it does not have a defined answer, or you run a single server that is connected to both networks that implements "views" based on source IP address. In the latter case, make sure that adequate security measures are in place to prevent a break-in from granting access to your local network.
Comment: This solved it! So if i have a computer in another country whatever and if he goes to foo.com and wants go get to my webserver, i use 192. Can mark as answer in 5 mins :(
Comment: I should also add that even if access to the local network isn't granted in the latter case, it would still give them the ability to manipulate the DNS of your workstations. Ill-advised all around, really.

Nameserver config: local or external IP


Are there apps to split one big screen into multiple spaces?

Question: I'm switching from three smaller screens to one big 42" monitor with Rectangle to emulate multiple monitors. It works great and I enjoy the flexibility in arranging the windows. However one thing missing is separate spaces. I used to have essential apps / documents on one 'main' monitor with others having multiple spaces. Now I have to switch the whole screen and have to go back and forth to find what I need. It's just a minor annoyance but I'm wondering are there apps to remedy this? By splitting one big screen into multiple smaller, virtual screens.
Answer: I had one on Windows called gridview.exe and there is a similar one for iMac https://macgrid.app/ 1wk demo
https://www.macupdate.com/app/mac/62836/grid $1.99   ? $5.99


What Budget DSLR has bracketing modes?

Question: I need recommendations on entry level budget DSLRs with plenty of bracketing modes (exposure, F-stops, etc for HDR and DOF shots). I am in Germany and am willing to spend upto €600. The brand doesn't matter to me. Also want to know if there are programmable bracketing modes available in entry level DSLRs.
Comment: The answers to this are getting pretty out of date (including mine!) illustrating the problem with this sort of question. I recommend closing and deleting this.
Comment: Maybe a good answer would be that of 2013 all/almost all entry level cameras offer this functionality and it is called x,y,z for Nikon, Canon, Pentax etc?
Comment: Answers to this will turn old, of course, but the question is good. Finally the last answer will be _"100% every DSLR in every price level can do it"_. Is this the case already?
Answer: The Pentax K30 is currently at €570 with the 18-55mm kit lens, and it includes a basic automatic bracketing mode, which will take three shots with different exposure. It also has an automatic in-camera HDR mode (also with three images), and a multi-exposure mode which automatically overlays the 3 with a simple blend.
You can choose how many stops to vary the exposure by, and what order (underexposed first, then regular, then overexposed, or another way) you want them in. And it'll take all three exposures with one click.
However, if you want more shots than 3, or if you want to vary something other than exposure (or choose which exposure parameter is varied), I don't think you'll be able to get it without spending more. (The almost-twice-as-pricey Pentax K-5II has many more options.)
Depending on your needs, you might be best served by a non-dSLR camera — specifically, a Canon point-and-shoot model running the CHDK firmware hack, which could give you very powerful programmatic control over bracketing.  (Models change all the time, of course; if you come back to this question a year from now, make sure to see what's latest.)
Or, you can, of course, simply bracket manually.
Comment: @gerikson — I think the top two companies have to be more concerned about their entry level models cannibalizing the midrange. Companies with a smaller market share have less to lose in that way.
Comment: I've heard (literally, in a podcast) that the new Nikon D5100 has built-in HDR function. Whether this can be changed from its default settings, I don't know.
Comment: @gerikson — I've only loosely followed the Nikon D5100. It looks like a _very_ nice camera. It's quite a bit more expensive than the Pentax K-r, though — currently €650 at amazon.de, without a kit lens, and over €1000 in a kit comparable to the Pentax one. I'm a Pentax user but am happy to recommend other brands; in this case, though, trying to stick to the given budget ruled that one out.
Comment: ok, I confess I didn't check out the price of the D5100 before recommending it. I also think that Pentax has the edge when it comes to advanced features in "entry-level" bodies compared to CaNikon....
Answer: With that budget, I believe you are looking at something along the lines of the Canon EOS 500D or the Nikon D5000. These are now slightly out of date cameras (still damn fine though) but newer entry level models (like the Nikon D3100) don't have bracketing.
Bracketing usually means auto-exposure adjustment, which is what you use for HDR. F-stop bracketing is more of a 'hack' - you set the AE bracketing as normal, but you set the camera to Shutter Priority, so that the camera is forced to adjust the aperture to modify the exposure.
I am not sure what you mean by 'programmable bracket mode'.
Comment: The D3000 has been replaced with the D3100. I believe the price points are the same though.
Answer: From what I know, any Canon SLR has it - it is called AEB (auto exposure bracketing).
I had it on my 400D (lowest model) and it is available on my 5D MK II.
You will however only get 3 exposures. Though I have found changing the shutter speed to shoot more images isn't an issue if you have a sturdy tripod. (And have successfully created a 40 and 60 exposure HDR).
If you look at the Canon website, you will find that the 1100D also contains AEB:
http://www.canon.de/for_home/compare_products/loadcomparator.asp?prod=2764B007AA;3820B001AA;5161B001AA;&lang=DE&country=DE&dir=/for_home/product_finder/cameras/digital_slr/
However I would rather use an older xx0D series camera than a xx00D series cameras.
Answer: My suggestion is the Canon 500D or 550D this is a really great beginner camera with magic lantern addon. Both models have Auto exposure bracketing enabled in the original firmware. But the Auto exposure bracketing is limited to 3stops and 3 images.
For additional settings there is a great firmware addon (free: Magic lantern) that adds a lot of options to the original firmware including exposure bracketing, shutter bracketing.
You can find out more about the magic lantern firmware on this site: Magic Lantern

HDR Bracketing Magic Lantern:
AE Bracketing for HDR images and timelapses.

In M mode, this function does shutter bracketing.
In the other modes it does exposure compensation bracketing.
Preview HDR images in camera
For each HDR picture set, Magic Lantern also writes a bash script for stacking the exposures with enfuse.

I have been using this firmware addon in combination with the Canon 550D for over a year now for creating HDR images, Timelapse and long exposures.
Even for a beginner Magic Lantern is simple to install and use.
::Edited the fact that the canon 500d and 550d do have auto exposure bracketing. Thanks Mike for pointing that out.
Comment: The 550D, at least, comes out of the box with exposure bracketing (up to 3 stops on either side) as well as white balance bracketing.
Comment: As the question is from a beginner, I don't think we should be talking about hacking the firmware.

Also it is untrue that these cameras don't have bracketing enabled in original firmware.  It is there, called Auto Exposure Bracketing (AEB).  p.86 of the manual confirms this - http://files.canon-europe.com/files/soft33601/Manual/EOS500D_EN_Flat.pdf
Comment: @Mike thank you for pointing that out. I correcte my mistake.
Answer: Sony SLT-A37 is a budget DSLR and it can do autobracketing.

Exposure bracketing (three shots)
Flash bracketing (in-camera flash)
White balance bracketing

$ : Adorama price is $479 atm with the usual 18-55 kit lens.
€ : Rajala Camera in Finland sells it with the 18-55 kit lens + Sigma 70-300 for 500 Euro.

Sony SLT-A57 is another one and a bit better equipped than the SLT-A37.
It can do the same bracketing modes as the A37, though I did not find confirmation for the flash bracketing in the A57 online manual. No reason why it would not work the same way as in the lesser cousin.
Pricing in general is right at your budget of 600 Euros, but one store in Germany sells it with kit lens (18-55 mm) for €512.

Sony SLT cameras use Exmor image sensor which should produce low noise photos even with high ISO numbers and/or in low light. This should work well in the situations where you might be needing the bracketing, in challenging lighting conditions.
Answer: You could try 'tethering' a camera to a PC - free software is available that has more bracketing functions. One is a .HTA file so written in Javascript - you could even re-program it yourself. I think I saw focus when looking at 'focus stacking' software. Google is your friend. I think it requires LiveView, but maybe only for seeing what you're doing on the computer as well as the camera ?

What Budget DSLR has bracketing modes?


Smoking on a public sidewalk?

Question: If an apartment complex has a no smoking rule and says "you cannot smoke on our property, including the public side walks surrounding the building or you will be fined" How can they enforce that against members of the public who smoke in public? Can they enforce it against tenants if it is part of the lease agreement?
Comment: Depending on the city this is located in some have regulations that include not smoking within a giving distance from the doors of a building.
Comment: @JasonAller, that is true but not germane to this question, as it would imply city law.
Comment: "No loitering" signs.
Answer: There is no public property on private land; there is private property where the public has implicit permission to be for legitimate purposes - shoppers in a shopping mall, visitors and residents in an apartment complex etc.
That permission can be revoked subject to any contractural (e.g. tenants) or statutory obligations (e.g. access for emergency services) at any time for any or no reason. For example, if the complex has a no smoking rule and a person persists in smoking after they can be asked to leave; if they don't leave, they are committing the tort and the crime of trespass.
Now, in common law jurisdictions, only governments have the right to impose punishment for offences; a fine is a punishment so an owner's corporation cannot impose one on anyone. They can sue for damages for torts or breach of contract but only to the extent of the damage caused (except in the US where punitive damages are a thing); so whatever damage the smoking/trespass caused; probably not much. Parties to a contract can agree on an amount of liquidated damages but to be enforceable they must be a genuine pre-estimate of the costs incurred by the breach; if they are too large they are a penalty clause and penalty clauses are unenforceable.
TL;DR
They can't. Maybe.
Comment: Thanks for the answer, but my question (and I should have been clear about this) refers to the easement sidewalks on the edge of private land.
Comment: If they are truly public sidewalks (as in owned by the city) then they have no control at all. If they are publicly accessible sidewalks on their land then see my answer.

Smoking on a public sidewalk?


Using server side validators with modal dialog (jquery)?

Question: Is there a straightforward way to use server-side validation with ASP.NET's validation controls in a form that's displayed in a modal dialog? I am using jQuery and SimpleModal (in C#, VS2010, .NET 4.0)
I've got a modal form which works fine. I need to use a server-side validation because the logic depends on data specific to the record being accessed
My solution for the project I'm working on now is to use a jQuery ajax call to pass all the form data to the server and get back the validation results before allowing the post to proceed. But this is relatively time consuming to implement, and in some situations I'm dealing with now all the validation code exists already.
The first challenge is that of course the modal dialog will close on a full postback. So you could put an UpdatePanel inside the dialog... without even thinking about this too much, though, I assumed that it wouldn't work out that well. It doesn't. And the form which opens the modal dialog to begin with is already in an UpdatePanel, which further confuses matters.
Anyway, I tried putting the contents of the modal form in an UpdatePanel for the heck of it. It does actually do a partial postback, the dialog remains open, but the contents of the dialog do not get updated with anything I change server side. If I close and re-open the dialog on the same page after testing the validation code, though, its contents are in fact updated to reflect these changes. Obviously the way the dialog is rendered is confusing ASP.NET. Or vice-versa. But this just seems sketchy from the get-go.
Rather than trying to hack my way through this problem I was hoping that others had some suggestions about a better way to approach this. Or just tell me I'm trying to hard too mix apples and oranges and I should keep it all client side (or client side + jQuery ajax) if that is the only sensible thing to do.
Answer: The two approaches I've taken:
1) submit the data via ajax, the response includes a success:true or false. If false, there is a message included that details the issue.
2) submit the form normally. If there is a validation problem, but the errors in a hidden div on the page and write JS to check for content in that div when the page loads and display the warning/error as necessary.


Does cross-validation shrinkage of the r-squared have anything to do with LASSO shrinkage?

Question: When you fit a model to a "learning" data set, and then apply the same model to new data, the coefficient of determination shrinks, and this "shrinkage" is a measure of how well a model predicts in new data versus the original data.  LASSO methods are used in estimating predictive models, and they rely on "shrinkage" of coefficient estimates for model selection.  Is this just an irritating and unfortunate coincidence that the same term refers to two different things in the prediction world, or do the two uses have something to do with each other?  I am interested in model selection methods that help minimize that first use of shrinkage, maximizing r-squared in out of sample data.  When I first saw the LASSO method ("Least Absolute Shrinkage...") I thought it was a short cut to a better predictor.  Seems like you still have to do something else to minimize shrinkage of the r-squared. I've done a lot of cross-validation work, but tried playing with a LASSO routine for the first time this week.  Is it the right direction to go?
Comment: I've never heard anyone use the word "shrinkage" in the first sense.  You are referring to "generalization error" there.
Comment: It must be used more commonly in Psychology and Educational Statistics.  Those articles are where I first encountered the term:  Yin, P., & Fan, X. (2001). Estimating R-2 shrinkage in multiple regression: A comparison of different analytical methods. JOURNAL OF EXPERIMENTAL EDUCATION, 69(2), 203–224.      If I can find search terms that help me separate the two, then I'll be happy.
Answer: The term shrinkage is used in regression modelling to denote two, somewhat related ideas.
The first relates to the slope of a calibration plot, which is a plot of observed responses against predicted responses. When parameter estimates are derived from one dataset and then applied to predict the outcome on an independent dataset, overfitting will cause the slope of the calibration plot (i.e. shrinkage factor) to be less than one, a result of regression to the mean. Typically low predictions will be too low and high predictions will be too high.
The second meaning of shrinkage (which is what the OP is asking) is a statistical estimation method that preshrinks regression coefficients towards zero so that the calibration plot for new data will not need shrinkage as its calibration slope will be one. Penalized maximum likelihood estimation is a general shrinkage procedure, in which both LASSO regression and Ridge regression are special cases.
More details can be found in:
F. E. Harrell, Regression Modelling Strategies, P75-78.
https://web.stanford.edu/~hastie/glmnet/glmnet_alpha.html


Lorentz Transformations involving Two Dimensions of Space

Question: I'm a high school student trying to understand the basics of special relativity, and I've been learning about the Lorentz Transformations. I understand that one transforms between the reference frames of two observers using the following equations:
$$x'=\frac {1}{\sqrt{1-\frac{v^2}{c^2}}}(x-vt)$$
$$t'=\frac {1}{\sqrt{1-\frac{v^2}{c^2}}}\left(t-\frac{vx}{c^2}\right)$$
Assuming that:
$$y'=y$$
$$z'=z$$
But what if $y'$ doesn't equal $y$, and the primed observer is moving relative to the unprimed observer in both the $x$- and $y$- directions (but still not the $z$-direction)? I couldn't find answers online, so I tried to come up with new equations to describe this. I read that motion does not cause length contraction in the direction perpendicular to the motion, so I assumed, perhaps wrongly, that the $x$ and $y$ coordinates would transform independently of each other according to their own separate velocities. For example, if two observers were moving relative to each other in the $x$ direction with velocity $v_x$, and they were moving relative to each other in the $y$ direction with velocity $v_y$, then one would use the following equations:
$$x'=\frac {1}{\sqrt{1-\frac{v_x^2}{c^2}}}(x-v_xt)$$
$$y'=\frac {1}{\sqrt{1-\frac{v_y^2}{c^2}}}(y-v_yt)$$
I thought that the time dilation would still depend on the total velocity, though. I calculated that the overall relative velocity $v_{total}$ would be:
$$v_{total}=\sqrt{v_x^2+v_y^2}$$
Furthermore, the difference in observed time would depend on the total distance of the event (which I guess is just the distance from the origin if on a graph). The total distance $d$, according to the unprimed observer, would be:
$$d=\sqrt{x^2+y^2}$$
Therefore, to calculate $t'$, one would use the equation:
$$t'=\frac {1}{\sqrt{1-\frac{v_{total}^2}{c^2}}}\left(t-\frac{v_{total}d}{c^2}\right)$$
However, when I tested out these equations, they didn't work. For example, when used on events with a spacetime interval of $0$, the interval did not remain $0$ after the transformation. Where did I go wrong, and what are the real equations that transform between the reference frames moving relative to each other in two spacial dimensions? If the math is too complicated for a sophomore high school student to understand, I would still love a conceptual explanation about what my approach missed. I hope this question makes sense.
Comment: It is basically not practicable to do Lorentz transformations in more than 1+1 dimensions without using matrices.
Comment: Have you seen that when a transformation acts on $[t, x, y]$ as a matrix (as Lorentz does) then $R M R^{-1}$ represents this transformation in a new basis? You'll want something like $R = [[1, 0, 0], [0, \cos \theta, \sin \theta], [0, -\sin \theta, \cos \theta]]$ where $\theta$ is the angle between the x-axis and the direction the thing is actually moving in.
Comment: @ConnorBehan, Thank you, but unfortunately, I haven't learned about matrices yet, and I think my trigonometry is pretty limited. Could you possibly tell me what I've missed in a more conceptual way?
Comment: @Buzz Thanks. Maybe I'm being redundant, but I would love a brief explanation for  why the the math gets more complicated with the added dimension. Is there another effect of relative motion in special relativity that complicates things? Have I assumed something that is wrong?
Comment: If you are just interested in velocity boosts along a single direction, you can choose that direction to define your $x$-axis.  However, as soon as you start combining Lorentz boosts along different velocity directions or boosts in combination with rotations, things get more complicated, because the transformations do not commute, and the only natural way to describe this is via matrices.
Comment: @L.B. I think "why the maths gets more complicated with added dimensions" might not be a meaningful question. If you try to write down the equations of the Lorentz boost without matrices, it's still very much possible. But I'm pretty sure you wouldn't enjoy juggling around with those 4 equations and solving for those 4 variables. Since Lorentz transformations are inherently linear transformations, the best way to describe them is to use a mathematical structure that makes handling such systems of equations easier, which, no surprises there, are matrices!
Comment: In fact, you can think of the 1D case as something which *looks* like a simplified version of the matrix equation because the other equations render trivial, not the other way round that the math becomes more complicated. The mathematical structure **always** had matrices!
Answer: Since you're trying to understand, I'll show you how to figure it out, instead of just telling you the answer. You don't need to know what a matrix is, and you don't need trigonomotry. Algebra is sufficient.
To avoid unenlightening distractions, I'll using units in which the speed of light is $c=1$. If you want to restore factors of $c$, just replace every $t$ in the following equations with $ct$. A Lorentz transformation about the origin is a linear transformation that leaves the quantity
$$
 t^2-(x^2+y^2+z^2)
\tag{1}
$$
unchanged. I'll show a couple of examples, and I'll show how to combine them to generate more examples — including the one you asked for.
 Ordinary rotation
One example of a Lorentz transformation is an ordinary rotation that mixes two spatial coordinates:
\begin{align}
 t &\to t\\
 x &\to ax-by \\
 y &\to bx+ay \\
 z &\to z
\tag{2}
\end{align}
with
$$
 a^2+b^2=1
\tag{3}
$$
Equation (3) is the same as saying $a=\cos\theta$ and $b=\sin\theta$ for some $\theta$, but we don't need to know that. Using (3), you can confirm that the replacement (2) leaves (1) unchanged:
$$
 t^2-\big((ax-by)^2+(bx+ay)^2+z^2\big)
 =
 t^2-(x^2+y^2+z^2).
\tag{4}
$$
 Boost
Another example of a Lorentz transformation is a boost that mixes one spatial coordinate with the time coordinate:
\begin{align}
 t &\to At+Bx\\
 x &\to Bt+Ax \\
 y &\to y \\
 z &\to z
\tag{5}
\end{align}
with
$$
 A^2-B^2=1.
\tag{6}
$$
Equation (6) is the same as saying $A=\cosh\theta$ and $B=\sinh\theta$ for some $\theta$, but we don't need to know that. Using (6), you can confirm that the replacement (5) leaves (1) unchanged:
$$
 (At+Bx)^2-\big((Bt+Ax)^2+y^2+z^2\big)
 =
 t^2-(x^2+y^2+z^2).
\tag{7}
$$
 Composing Lorentz transformations
Here's the key: given any two transformations that both leave (1) unchanged, their composition clearly also leaves (1) unchanged. "Composition" just means making one replacement after the other. In particular, making the replacement (5) followed by the replacement (2) is equivalent to making the single replacement
\begin{align}
 t &\to At+B(ax-by)\\
 x &\to Bt+A(ax-by) \\
 y &\to bx+ay \\
 z &\to z.
\tag{8}
\end{align}
Even better, we can first do (2), then do (5), and then do (2) with the opposite sign for $b$. The result is
\begin{align}
 t &\to At+B(ax+by)\\
 x &\to a(Bt+A(ax+by))-b(ay-bx) \\
 y &\to b(Bt+A(ax+by))+a(ay-bx) \\
 z &\to z
\tag{9}
\end{align}
There you go. That's a Lorentz boost along an arbitrary direction in the $x$-$y$ plane. Notice that it leaves two of the original spatial directions unchanged, namely $z$ and $ay-bx$, so it qualifies as a boost in the $ax+by$ direction.
 Relating $A,B$ to velocity
I used a notation that highlights how simple the concepts are. To relate my quantities $A,B$ to the velocity of the boost, use $v=B/A$. In the case (9), the components of the velocity are $v_x=Ba/A$ and $v_y=Bb/A$. If you want to use Standard International units, just multiply these velocities by $c$.
 Perspective
At the beginning of this answer, I said that you don't need to know what a matrix is, and you don't need trigonomotry. Maybe I should have said that you already know everything you need to know about matrices and trigonometry! The idea of composing two linear transformations to get another linear transformation is what matrix algebra is all about. Going from (2) and (5) to (8) is an example of matrix multiplication, even though we didn't use matrix notation. Equation (3) is the foundation for ordinary trigonometry, and equation (6) is the foundation for hyperbolic trigonometry.
Regarding Lorentz boosts in arbitrary directions, you might be interested in the related question Lorentz boost matrix for an arbitrary direction in terms of rapidity, but you already know everything you need to know: start with the boost (5), and compose it with whatever rotation(s) you want to point the velocity in the desired direction.
Answer: The very first step, where you assume that you can apply the transform simultaneously in two directions is wrong. If you first transformed from $(t,x,y,z)$ to $(t',x',y',z')$, and then applied a second boost with the new $t'$, then at least you'd know that your result was physical, even if the overall boost you get is incorrect. But you tried to smoosh the two boosts together into one step and there's no guarantee that what you got has any physical meaning. Now, even if you do the two boosts separately according to your plan, you end up in a frame moving at the wrong velocity, but at least it is a well defined frame, so we can see what went wrong.
Consider what it means to boost up to a velocity. It means that an object that previously looked to you as moving with that velocity now appears to be at rest. Say you have such a "pacemaker" set up, so that it passes the point $(t_0,x_0,y_0,z_0)=(0,0,0,0)$ in your original coordinates and later passes $(t,x,y,z)=(1\,\mathrm{s},v_x\cdot1\,\mathrm{s},v_y\cdot1\,\mathrm{s},0).$ After your two boosts, you want $(x'',y'',z'')=(0,0,0)$ (you don't care about $t''$). Ok, so perform your first boost in the $x$ direction with velocity $v_x.$ What do you see now? I get that the pacemaker event now occurs at $(t',x',y',z')=(\sqrt{1-\frac{v_x^2}{c^2}}\,\mathrm{s},0,v_y\cdot1\,\mathrm{s},0).$ Note that the reference point $(t_0,x_0,y_0,z_0)=(0,0,0,0)$ remains invariant. If you calculate the remaining velocity of the object in the $y$ direction, which is $\frac{y'}{t'},$ you see it has increased. So the issue with your original plan is that, once you perform the first boost, the time dilation of the intermediate frame causes the velocity you have to match with your second boost to increase. Perform the second boost with the adjusted velocity and you will see the object come to rest as desired.
So what have we learned? If you want to boost up to velocity $(v_x,v_y,0),$ you can first apply a boost in the $x$ direction of $v_x$, and then apply one in the $y$ direction with the adjusted velocity $\frac{v_y}{\sqrt{1-\frac{v_x^2}{c^2}}}$. This will still not be quite right, because now your frame will suffer Wigner rotation: the $x''$ and $y''$ axes are unexpectedly no longer parallel to the original $x$ and $y$ axes, which can be avoided by using a more complicated derivation for the boost (as indicated in the comments), but if you don't care about that then this might be fine.
Try your hand at extending this scheme to all three dimensions.

Here follows a somewhat overkill derivation of boosts in general directions. If what you say about your skill is true, you won't understand this right now, but just consider it something of a goal.
The matrix $$\boldsymbol\eta=\begin{bmatrix}-1&0&0&0\\0&1&0&0\\0&0&1&0\\0&0&0&1\end{bmatrix}$$ is of fundamental importance to special relativity. Consider a vector quantity $\mathbf{x}=\begin{bmatrix}ct&x&y&z\end{bmatrix}^T$ measured in some reference frame. The quantity $\mathbf{x}^T\boldsymbol\eta\mathbf{x}=-c^2t^2+x^2+y^2+z^2$ remains the same in every reference frame, even as the components of the vector change. Specifically, a vector quantity's components change under a Lorentz transformation as $\mathbf{x}'=\mathbf{\Lambda x},$ where $\mathbf{\Lambda}$ is a matrix associated with the transformation. Then we must have $\mathbf{x}^T\mathbf{\Lambda}^T\boldsymbol\eta\mathbf{\Lambda x}=\mathbf{x}'^T\boldsymbol\eta\mathbf{x}'=\mathbf{x}^T\boldsymbol\eta\mathbf{x},$ and so we find that Lorentz transformations are represented by matrices where $\mathbf{\Lambda}^T\boldsymbol\eta\mathbf{\Lambda}=\boldsymbol\eta.$
Now, we bring in the big guns: the theory of matrix Lie groups. We ask, what do really small Lorentz transformations look like? Well, they should look like $\mathbf{\Lambda}=\mathbf{I}+\epsilon\mathbf{H},$ where $\mathbf{I}$ is the identity matrix, which does nothing when multiplied onto anything else, $\epsilon$ is a small real number controlling the size of the transformation, and $\mathbf{H}$ represents the "kind" or "essence" of the transformation. Plug that into the defining $\mathbf{\Lambda}^T\boldsymbol\eta\mathbf{\Lambda}=\boldsymbol\eta$ and get $\epsilon\boldsymbol\eta\mathbf{H}+\epsilon\mathbf{H}^T\boldsymbol\eta+\epsilon^2\mathbf{H}^T\boldsymbol\eta\mathbf{H}=0.$ Drop the $\epsilon^2$ term (we're only interested in linear/first-order variations) and rearrange to $\mathbf{H}=-\boldsymbol\eta\mathbf{H}^T\boldsymbol\eta.$ Now eliminate as many equations as you can to arrive at $$\mathbf{H}=\begin{bmatrix}0&\xi_x&\xi_y&\xi_z\\\xi_x&0&-\theta_z&\theta_y\\\xi_y&\theta_z&0&-\theta_x\\\xi_z&-\theta_y&\theta_x&0\end{bmatrix}.$$
This is the generator of Lorentz transformations. The remaining variables are just the ones that you don't end up solving for. If you plug in values for them, you can get a Lorentz transformation with the matrix exponential $\mathbf{\Lambda}=\exp(\mathbf{H}).$ By plugging in zero for all but one of them, you can come to understand what each one means. I have thus named them according to function: $\xi_x,\xi_y,\xi_z$ are "rapidities" for boosts, related to velocities by $\xi=\operatorname{artanh}(\frac{v}{c})$), and  $\theta_x,\theta_y,\theta_z$ are rotation angles.
Now we have a way to make a formula for all boosts. If you want to boost with velocity $v_x,v_y,v_z$, first calculate the total velocity $v=\sqrt{v_x^2+v_y^2+v_z^2}$ and rapidity $\xi=\operatorname{artanh}(\frac{v}{c}).$ Then find the rapidity vector $\xi_i=-v_i\frac{\xi}{v}.$ Plug these rapidities into $\mathbf{H}$ and null out the spatial rotations. This matrix has the following properties: $$\begin{align}&\mathbf{H}^0=\mathbf{I},\\&\mathbf{H}^{2n+1}=\xi^{2n}\mathbf{H},\\&\mathbf{H}^{2n+2}=\xi^{2n}\mathbf{H}^2.\end{align}$$ These are useful because $$\begin{aligned}\mathbf{\Lambda}&=\exp(\mathbf{H})=\sum_{k=0}^\infty\frac{\mathbf{H}^k}{k!}\\&=\mathbf{I}+\sum_{k=0}^\infty\frac{\mathbf{H}^{2k+2}}{(2k+2)!}+\sum_{k=0}^\infty\frac{\mathbf{H}^{2k+1}}{(2k+1)!}\\&=\mathbf{I}+\frac{\mathbf{H}^2}{\xi^2}\sum_{k=0}^\infty\frac{\xi^{2k+2}}{(2k+2)!}+\frac{\mathbf{H}}{\xi}\sum_{k=1}^\infty\frac{\xi^{2k+1}}{(2k+1)!}\\&=\mathbf{I}+\frac{\mathbf{H}}{\xi}\sinh\xi+\frac{\mathbf{H}^2}{\xi^2}(\cosh\xi-1).\end{aligned}$$ This finally gives an explicit expression for the Lorentz transformation matrix $\mathbf{\Lambda}$ associated with a given velocity.
Expanded out in terms of the coordinates and with all the hyperbolic trig simplified away, $$\begin{alignat}{10}
t'&=&\gamma t&{}+{}&-\gamma \frac{v_x}{c^2}x&{}+{}&-\gamma \frac{v_y}{c^2}y&&-\gamma \frac{v_z}{c^2}z&,\\
x'&=&-\gamma v_xt&{}+{}&\left(1+(\gamma-1)\frac{v_x^2}{v^2}\right)x&{}+{}&\frac{v_xv_y}{v^2}(\gamma-1)y&{}+{}&\frac{v_xv_z}{v^2}(\gamma-1)z&,\\
y'&=&-\gamma v_yt&{}+{}&\frac{v_xv_y}{v^2}(\gamma-1)x&{}+{}&\left(1+\frac{v_y^2}{v^2}(\gamma-1)\right)y&{}+{}&\frac{v_yv_z}{v^2}(\gamma-1)z&,\\
z'&=&-\gamma v_zt&{}+{}&\frac{v_xv_z}{v^2}(\gamma-1)x&{}+{}&\frac{v_yv_z}{v^2}(\gamma-1)y&{}+{}&\left(1+\frac{v_z^2}{v^2}(\gamma-1)\right)z&\end{alignat}\\
\left(\gamma=\frac{1}{\sqrt{1-\frac{v^2}{c^2}}}\right).$$
This boost does not cause any unwanted rotations. But good luck remembering it!
Answer: Consider the simple case of a single inertial observer, sitting alone in space without accelerating.
Coordinates like $x, y, z,$ and $t$ are simply labels for different points/events in spacetime (we call them "points" if we only care about $x, y, z$, and "events" if we care about $x,y,z,t$). Choose the labels in certain ways, and they have convenient properties, like the (spacial) distance between two points is $\sqrt{\Delta x^2 + \Delta y^2 + \Delta z^2}$. It is usual to pick coordinates that are "orthonormal", which basically means that each coordinate axis is perpendicular (orthogonal) to the others, and a unit distance along one axis is the same distance along another axis. It makes the distance rule I gave above work.
Since reality doesn't work in terms of coordinates,it is possible for our single observer to have and use multiple different coordinate systems, depending on what is most convenient for them. They could have two orthonormal spacetime coordinate systems with different origins, or different spacial axis (as long as in each set, they are orthogonal and normalized), or different "parity", and the two systems would be related to each other by spacial rotations, spacetime translations, and reflections. Given the coordinates $(x,y,z,t)_1$ of a event in coordinate system 1, you could easily compute the $(x,y,z,y)_2$ of the event in coordinate system 2.
What this means is that if our single observer sees an object moving with a $v_x \neq 0, v_y \neq 0$, then our single observer also has available to them a different coordinate system, gotten by rotation from the first one, where $v_x \neq 0, v_y = v_z = 0$. The equations of motion of that object are completely compatible with each other in either coordinate system.
You could also think of it as two observers motionless relative to each other who each have their own orthonormal coordinate system. If Alice sees and event at $(x,y,z,t)_{Alice}$, she can tell Adam to look at $(x,y,z,t)_{Adam}$ to see the same event.
Now consider your situation, Alice and Bob are moving relative to each other. The Lorenz Transformation, as normally written with $(x,y,z,t)_{Alice'} = (\gamma (x-vt),y,z,\gamma(tc^2 - vx)/c^2)_{Bob'}$, already assumes that both Alice and Bob have applied rotations and translations (and possibly a reflection) to their own preferred coordinate system to get a pair of coordinate systems that share an origin (in both space and time) and at time 0 all three sets of spacial axis correspond.
It is perfectly reasonable to start with coordinates in system Alice, convert to Alice' using rotations and translations, convert that to Bob' using a Lorenz boost, and then convert finally to coordinate system Bob to see where Bob should look for the event.
Each of those coordinate transformations is a messy calculation. To teach Special Relativity, a lot of the mess can be avoided by only working with Alice' and Bob' -- and perhaps Charlie', who happens to be on a parallel course with Alice' and Bob'. It was generally assumed that the rotations and translations were nothing new to the physicists first learning SR, and thus were unimportant to mention except in passing.