RePaint area (region) in sdi view MFC

Question: I want to ask you one question about SDI MFC application.
How can I repaint some area (region) on the view in SDI MFC application but without repaint complete view?
Answer: Use ::InvalidateRect() and/or CWnd::InvalidateRect().
Answer: Have a look at the Invalidate functionality. You can invalidate a rectangle, a region or the while window.
An invalidated region will be repainted with the next WM_PAINT message. In your OnPaint() method you can query the clipping region from the CDC object. If the object in question is not withing the region/rectangle, you can skip drawing it.

RePaint area (region) in sdi view MFC


Player gets injured every week in Manager Mode

Question: On Fifa 12 Ipad, one of my players ( N. Wedderburn) got injured one match. It was a Back Strain or something, and it said he would be injured for like 5 weeks. The next match though, it then said he had whiplash and would be out for a week. This then kept happening after every match, but with different injuries and dates each time. Now I haven't been able to play him for 10 matches. How can I stop him from being injured so I can finally play him?
Comment: Have you tried to decrease the level of injury via settings ?
Answer: I had the same problem
The problem was that he didn't play because he was injured, but he was still in my starting line-up. When I replaced him the problem was solved!


Radiator cap build up

Question: So I pulled the thermostat to see if that was bad and it was still good also checked my oil and it wasn't milky but I pulled the radiator cap off and this was built up on it  And I'm wondering what may cause this
Comment: A bit more information would be helpful. Make, model year and mileage on vehicle?  Note, if I had to guess somebody added a lot of leakstop to that coolant system. If you grind up that black sludge in your fingers, does it feel gritty, like small grains of sand?
Comment: Welcome to Motor Vehicle Maintenance & Repair! What exactly is your question?
Comment: It is a 03 cheverolet s10 xtreme 4.3L and it does feel gritty
Comment: @zipzit Sounds like an answer to me.
Comment: Mileage on vehicle?  Can I assume you purchased this vehicle used? (Or are you did you purchase it new in 2003?)  Obviously if you purchased it new, I'd expect you to know its repair history.
Comment: It has 160,000 miles on it and yes I bought it used it had a 135,000 when I purchased it
Answer: So I'm guessing at one time your vehicle had a slight coolant leak.  The owner added some coolant stop leak to the system.  There are lots of forms of this... here's a typical summary.  I know lots of folks have recipes for leak stop stuff.. the one I remember from old skool mechanics is to use raw ground pepper as a leak stop filler.
Generally stop leak adds small granular material to the coolant system.  The theory is that these small particles migrate to the leak locations and plug the holes.  And I'm not saying that's a bad thing.  At the manufacturer I worked at we added this material to the coolant system of each and every new vehicle built.  The material we used came in a compressed pellet, which when added to the radiator after coolant evacuation and fill would migrate throughout the system.  The pellets were basically just ground up almond shells.  No kidding.  Almond shells.   It seemed to work, and I remember a particular new model launch issue where we proved that the stuff was necessary. We never saw any system (quality) degradation anywhere from its use.
The stuff you have seems like more of the same, likely of a different form.  There are liquid versions of the stuff, and I'm guessing that's what you have. Probably lots of it. I wouldn't worry about the sludge. Note: once in there, you can not get it out again.  Trust me, I've tried (when I had that issue at a new model launch.  One the stuff is in there it stays in there...)
But... with that said, that stuff was added for a reason. Please do test your coolant system, check for leaks.  Verify the radiator cap is in good shape, and that your overflow (and coolant return) system works well.  Keep an eye on that. You don't want to run dry, overheat your engine, etc...
Good luck with it.

Radiator cap build up


Armory wallet and bitcoin - newbie questions

Question: I made a transaction into my armory wallet but I didnt downloaded blockchain before. What happened to my bitcoin?
Can I access my bitcoins when ill be able to get the wallet online?
Answer: A wallet stores private keys, not bitcoins (and a watching-only wallet just stores addresses, without their private keys). Your bitcoins are "stored", for want of a better word, on the global distributed ledger. You can verify this by looking up your address/addresses (not your private keys!!!) on a blockexplorer web site such as blockchain.info — this will show you that your bitcoins are at whatever address/addresses you sent them to. You can do this even if Armory hasn't downloaded the blockchain.
In order to construct a transaction, Armory needs a local copy of the blockchain and it needs the [public] address/addresses from which you're spending. But the transaction will not be valid until you have signed it, and for that, you need the private keys. In a secure set-up (cold storage), you construct transactions in a watching-only wallet (connected to the internet), and you sign them in a full wallet (on an air-gapped computer); such that your private keys are never exposed to the internet.


Pin mount of horizontal pins without bending

Question: Related to my question from last time (Pin mounts horizontal pin rows): I have the same device, but now I don't want to bend the legs, rendering SIP/DIP sockets useless. But I do not care anymore about the removability. What are then good ways to fixate the device on a pcb? One idea I had was to use overdimensioned smd pads, and solder it on them. Is that useful, or are there better ways?
Comment: Any chance you can find the device's datasheet?
Comment: http://www.amstechnologies.com/fileadmin/amsmedia/downloads/4106_1550hpsinglemodelaser.pdf
Answer: You could use some right-angle female connector strips, but obviously from the topology once the leads are inserted and the strips soldered into a PCB it will no longer be possible to remove the laser. Photo from Sparkfun, but the parts are widely available from any distributor:"-

Comment: Well, you could put a matching SIP header on the PCB, but this is asking for trouble as both the laser and TEC draw about 2.2A each.
Comment: @rdtsc Indeed. Probably within ratings but with the contacts just floating there, the ratings may not be valid.
Answer: It isn't mentioned in the datasheet, but first of all, this module needs to be heat-sunk (bolted to something thermally conductive) to keep it cool. A dab of heat-sink grease (or pad) should be used to ensure good thermal transfer. The laser diode can be pulsed with up to 2.2A of current, which would quickly overheat it otherwise.
It looks as though it is intended to have a cut-out made on the PCB, and the device placed through the cut-out, with the legs touching the PCB, which are then soldered. Finally, mounting screws secure it to the case or a heat sink.
Interestingly, it also includes a TEC or thermo-electric cooler (peltier junction) device to help cool it, and a thermistor to measure it's temperature. If you do not already have a "driver" circuit for this beast, one would be required to:

Measure the temperature of the device (thermistor.)
Send power pulses to the laser (carefully regulated and limited.)
Monitor laser power output, adjust power accordingly (photodiode.)
As the temperature increases, begin powering the TEC to maintain temperature.
If the temperature cannot be controlled (too hot), shut down device.
If current or voltage limits to the laser are exceeded, shut down device.

Such a driver is likely something like one of these: http://www.laserdiodesource.com/laser-diode-drivers
I did manage to find one paper  mentioning this module, but cannot find a reference driver circuit.
Designing such a driver will not be an easy or simple task.
Comment: I have already a driver, and a cooler. The problem is our current fixation system (aka free-air-connections). Thus I wanted to design a pcb for that (with a gap in the middle) where the diode can be fixed onto.
Comment: Good, then just make a cut-out slightly larger than the laser base, optical fiber, and screw holes, and leave appropriate pads to solder the leads to. Could place the laser through the PCB, or easier, place the PCB on top of the laser and use bottom pads. Many PCB fab houses can route out areas of the PCB using a 100mil/2.54mm router bit. If your PCB is large, you will have to use PCB standoffs of some height (to be calculated by where you want the base of the laser module to reside - on the enclosure, through the enclosure?)


How can I write a good answer?

Question: Sometimes an answer needs to be formatted with math formulas. I think that we should create a tutorial for new members on how to write a good answer. As in my case, I don't know how to write those formulas. Where can I learn that?
Answer: There's a tutorial and links to more information on the Mathematics Meta site: MathJax basic tutorial and quick reference.
The Help Center page Editing Help mentions this website as another reference.
Comment: i have a little bit of knowledge in latex, good answer!
Answer: A good starting point for your questions headline would be this help center page. However, this is just a guideline that does not mention and explain the specific tools you can use to write good answers.
Since your text focusses mainly on math formulas: Many (not all) Stack Exchange sites support MathJax which gives you the ability to insert LaTeX formulas into your text. You can either use inline equations with $...$ to include symbols and formulas directly into your text. For example this one $a^2 \cdot \sqrt(x)$ was created with $a^2 \cdot \sqrt(x)$. Alternatively, you can write formulas in a separate line using $$...$$. For example:
$$\frac{1}{2} \int_0^1 \gamma x^2 \;\textrm{d}x$$
This was generated with $$\frac{1}{2} \int_0^1 \gamma x^2 \;\textrm{d}x$$. Note that the syntax to start and end the math environment might differ slightly on different SE pages. If you don't know how to code in LaTeX you have to search for it on the internet since it is an external tool and there are already a lot of tutorials out there (Or simply follow the links of Glorfindels answer).
Hint:
If you see some special technique or tool in other questions/answers and you don't know how to use it a good trick that might help you is just hitting the edit button. It will give you access to the complete source code of the post and you can examine how the feature of interest was implemented. Just watch out that you don't accidentally submit an edit.
Comment: i will use the edit button to create my question

How can I write a good answer?


Opening the wsp file in Visual Studio for Sharepoint Migration

Question: I am trying to open wsp file in visual studio but it was asking me to install Sharepoint server which I dont want to do. I tried converting the wsp to .cab and extracted it, by doing that I was able to open the content files in notepad. But I was looking for a way to open all files(like opening all files by selecting only the .sln file for asp.net web applications) since the wsp file needs code change and we need to build the solution for deploying it. Please help me out as soon as possible.
Answer: The wsp does not contain the sln. You can rename it to cab and extract it as you already mentionend. After extracting it you the the whole Content. Nothing else is included in the wsp.
Comment: ..Thank u Stefan. Now I have my extracted files to the folder. And I am able to only file by file in visual studio. Is there any way of opening all the files at once. And how can I build all the changes so that I can make a deploy-able file. Kindly explain (the procedure) to build and deploy. It would be so much helpful ! Thanks
Comment: Any response would be appreciable !


Can you tell if your friends are playing without going all the way in-game?

Question: I'm new to World of Warcraft and I'm only really interested in playing when certain friends are online. Is it possible to view the status of friends in your friends list without launching WoW and fully entering the game?
Comment: Related: [Is there a stand-alone chat client for Battle.net](http://gaming.stackexchange.com/questions/10890/is-there-a-stand-alone-chat-client-for-battle-net)
Comment: Do you like playing Starcraft 2? ;)
Answer: To my knowledge Blizzard has not yet provided a way to view friend status from outside of their games. So you'll have to go with a 3rd party solution.
I use Steam to launch World of Warcraft. Steam will notify my friends when I launch a game, and vice-versa. Most of my friends also use Steam, which increases the value of Steam tremendously. There's little quite as satisfying as launching WoW and then seeing 4 more of your friends follow your lead. One downside to Steam is you have to own at least 1 game on the service to get the friend features.
Also, steam doesn't tell you what character they're on, but once you're in the game  RealId can help figure that out really quickly. If you don't use RealId with these friends, there are a number of friend-synching addons you can use to keep track of friends across multiple characters on the same server/faction.
There are also a few alternatives to Steam (XFire?) for keeping track of what your friends are playing. A common thread across all of these is that all your friends will want to use the same program.
Comment: "One downside to Steam is you have to own at least 1 game on the service to get the friend features." Do you?  The client can be downloaded for free [from their site](http://store.steampowered.com/about/).
Comment: and even if you do, go and pick up one of the great indie games for a pittance.
Comment: @Powerlord: You can download the steam client for free, and buy games, etc. But in order to use the "Community" features, you must make a purchase first.
Answer: I know this is an old question, but Blizzard recently added the Mobile Guild Chat feature to the Mobile Armory. For a small premium fee, you can sign in to the guild chat and see which of your guild members are online, as well as chat with them. Assuming your friends are in the same guild as you, this is the best option by far.
Comment: The mobile armory guild chat is pretty cool, but I disagree that it is "the best option by far." It costs extra money every month, and that's a pretty significant downside. I'll continue to use my Steam client with no monthly fee until Blizzard provide something... free-er.
Comment: Well, the fee also allows you to access the remote auction house so it isn't solely a chat feature. Certainly it isn't the best option in terms of cost, but in terms of actually allowing you to connect with your friends, Steam doesn't seem viable to me unless you are so persuasive that you can convince 60 or 70 friends/guildmates to download steam and open WoW via that client every time. Not to mention that you only need to be on your phone, rather than on your computer.
Comment: This is now free!
Answer: When you say 'friends' you mean not your character's friends but your realid 'friends'.
Currently you cannot do this, the closest you get is after you login to the community site you can browse the friends of your characters. Soon, just not today. Though these are your real life friends, often people have access to these people in im/chat like other people noted.
The direct connection between 'character friends' and 'realid' to web services likely won't happen, since anyone can /friend another person. That's just way too intensive.
Comment: Yea, it's just annoying to manually go down my friends list and "Are you playing WoW" each of them and wait for responses. Especially as not all of them pay attention to IM while in-game.


When should you build a web application vs. a thick client?

Question: I would like to hear other people's advice on when one should build a web application versus building a thick client.
Over the last few years, I have participated in several discussions about whether an application should be built (or an old application upgraded) with a web browser interface.  Usually these were internal systems used within an organization, not mass-market shrink-wrap products, and they were not actually on the public Internet.  I do not want to limit the discussion to these types of applications solely though.
There are obvious cases where an application should be one or the other (e.g. no web based video editing software).  On the other hand, Javascript libraries are making more rich experiences in the browser less difficult to implement everyday.
Have Javascript libraries and advanced server side technologies made things such as right-click context menus, drag and drop, etc. doable on the client side without a large effort?  At what point does the extra complexity of writing for the web override the benefits such as ease of deployment and cross-platform compatibility, particularly if you are not trying to create the next Stack Overflow, but instead just building an internal application?
Does the fact that an internal application has a limited and captive audience more or less override any concerns over improved usability that a thick client can provide?
Comment: http://www.google.com/search?q=web+based+video+editing
Comment: Thanks for that link, guess you have to be careful what you say!  though in my defense, these are generally not the type of app I meant either. :)
Answer: I go Web app when I don't want to:
- be supporting a thousand environments each with their own quirks.  Specifically, viruses, trojans, software interfering, and making it work the same everywhere.
- worry about applying upgrades and taking lots of calls
- dealing with clients who lose their data
I pick a thick client when the computation is intensive per transaction, or there is significant data transfer per transaction.
I like fixing everyone's problems with one upgrade.  It might not be for everyone, but it's where the quality of my life and those I work for goes up.  Making a web app work on a few different browsers may be easier than a ton of different operating systems in different conditions.
With the advent of Flex/Air you can provide an entire application experience in the browser.  The browser is becoming the universal interface, whether it's installed locally or in the cloud.
Web apps have their cons too.  I just am more motivated to build web apps as the pro's seem to outweigh the cons for the projects I am choosing.
Answer: I believe we are still at the point where unless there is a reason for it to be a Web app it should be a local application (thick).   It is obvious when it should be a web app.  A pet peeve of mine is the thought that it should be a web app unless it's obvious it should be local.  I don't believe we are at the point where enterprises are willing to have their employees dependent on web applications outside of their control.  When it comes to apps internal to a company I believe movement of data, security, and deployment/upgrades are the key factors in deciding.
A couple of key reasons for an app to be on the web.

The application and data need to follow you around no matter what computer you are on.
The data needs to be centralized and the amount of data that needs to be transferred to the client is reasonable.

A few reasons to use thick apps:

Utilities that work on local resources.
Apps that do lots of one time processing of data.
Apps where data needs to be accessed when disconnected from the network.
Answer: Things I remember from the bad old days of deploying internal applications that weren't web-based:
There was always a minimum of one computer that was set up so differntly that the upgrade wouldn't work. Sometimes more and the problem was different for each machine that wouldn't work.
There was always a user who refused to install the upgrade until forced to by management (usually several weeks or months later). This ended up causing problems in the data at times becasue new businesss rules were not enforced.
Comment: this has now been replaced with the golden age of cross browser compatibility hell


symfony doctrine build-sql error

Question: I have some big problems with symfony and doctrine at the beginning of a new project. I have created database diagram with mysql workbench, inserted the sql into phpmyadmin and then I've tried symfony doctrine:build-schema to generate the YAML schema.
It generates a wrong schema (relations don't have on delete/on update) and after this I've tried symfony doctrine:build --sql and symfony doctrine:insert-sql
The insert-sql statement generates error (can't create table ... failing query alter table add constraint ....), so I've decided to take a look over the generated sql and I've found out some differences between the sql generated from mysql workbench (which works perfect, including relations) and the sql generated by doctrine.
I'll be short from now: I have to tables, EVENT and FORM and a 1 to n relation (each event may have multiple forms) so the correct constraint (generated with workbench) is
ALTER TABLE `form` ADD CONSTRAINT `fk_form_event1` FOREIGN KEY (`event_id`) REFERENCES `event` (`id`) ON DELETE CASCADE ON UPDATE CASCADE;

doctrine generated statement is:
ALTER TABLE event ADD CONSTRAINT event_id_form_event_id FOREIGN KEY (id) REFERENCES form(event_id);

It's totally reversed and I am sure here is the error. What should I do? It's also correct like this?
Comment: The SQL generator is old. Don't use it. Write your schemas in YAML and you get to control exactly what SQL is generated. It isn't hard.
Comment: It's not really acceptable that the Doctrine SQL introspection is limited/broken (if that's true) - this is definitely not the case with Propel. YAML is an inferior tool for database design than, say, DBDesigner and just because it's easy *enough* doesn't mean there isn't a fair point to be made about making it even easier.
Answer: It it broken, I've wrote the schema manually and it works perfect. I didn't want to do that because it was a very large file, but I've also learned from it!
Thank you guys!
Answer: To get both visual representation and automatic code generation you can use ORM Designer so you will have everything covered by one tool.

symfony doctrine build-sql error


What languages reinforce imperatives with conjunctions?

Question: In Italian, the conjunctions "ma" ('but') and "e" ('and') can preface imperatives to reinforce them as in: "ma/e vieni!" ('do come!').
Does anyone know of any languages that display this phenomenon as well?
Comment: Comments are not for extended discussion; this conversation has been [moved to chat](https://chat.stackexchange.com/rooms/103684/discussion-on-question-by-nico-what-languages-reinforce-imperatives-with-conjunc).
Answer: The order is really arbitrary or a result of the syntactic constraints of the language.
(Generally SAE requires imperatives take the first position whereas even in neighbouring Eastern European IE Your food eat! Or Home go! are perfectly normal.  Accordingly generally the SAE imperatives do not have unique morphology to make it clear that they are imperatives.  So one role of these particles in SAE may just be to mark the imperative, not unlike -le in colloquial Spanish.)
That constraint lifted, one parallel here is to the German "flavouring particles", like doch and ja, when used in an imperative phrase.  In Russian there is ну, in Armenian դե, բա and բայց.  The former are roughly like English well, the latter is literally but but even more than English though and German doch its position is very free, including in imperatives.  In certain contexts Russian и can even be used in imperatives, where it means too or also (Ну и сделай!).
Their function is not exactly just reinforcement, it may even be softening, but that's often the practical effect.  (My Italian Sprachgefühl is weak here but it says that in Italian it is not exactly reinforcement either.)
The English Wikipedia article https://en.m.wikipedia.org/wiki/German_modal_particles, like most of the talk on this, implies that flavouring particles are somehow unique to German, but of course, as you and I have shown, it's not.  What's relatively unique in modern SAE is freeish word order, which is why they are called "particles" not "conjunctions".
(I would argue that English and in And don't come back! mentioned in comments by Draconis is indeed productive.  Productiveness doesn't mean a feature can be used in all situations, just that it can be used in (some) new ones.)
Comment: Comments are not for extended discussion; this conversation has been [moved to chat](https://chat.stackexchange.com/rooms/103683/discussion-on-answer-by-adam-bittlingmayer-what-languages-reinforce-imperatives).


Calculating two diagonal forces

Question:
When I tried to calculate the force exerted on the rope 'a' I get that it is equal to 5N when the block has a force of 10N. Do I instead need to divide by 30 since the sum of the two angles is 30 degrees? Should I be using the cosine of the angles so that it is (cos(10) / cos(20)) * 10? I just need to calculate the force exerted on rope 'a'. Thanks.
Comment: The tag kinematics is not applicable here. This is just Newton's 3rd law.
Answer: What you need to consider is the equilibrium of the body.
On the vertical axis Y, there is the F=10 N force, and the vertical components from the forces of the ropes, ie:

$F_{A,y}$: the vertical component of the force from rope A
$F_{B,y}$: the vertical component of the force from rope B

Additionally on the X-axis (horizontal), you only have two forces

$F_{A,x}$: the horizontal component of the force from rope A
$F_{B,x}$: the horizontal component of the force from rope B

The forces are presented in the following graph

In both cases the sum of the forces in each axis should be zero. i.e.:

$\sum F_x =0 \Rightarrow -F_{A,x}+ F_{B,x}=0$
$\sum F_y =0 \Rightarrow F - F_{A,y}- F_{B,y}=0$

Also, the relationship between the components of the forces and the force on the rope will follow the following relationship .
$$F_{A,x} = F_{A}\cdot \sin(\theta_a) \qquad F_{A,y} = F_{A}\cdot \cos(\theta_a) $$
I only wrote for rope A, because I think this looks like homework. Although you  have showed what you've tried, its far away from being correct, so I tried to put you in the right track. Hopefully you will be able to find the solution.  I'd be happy to assist more if you update your solution.
Answer: There is a piece of important information missing from the problem statement - whether the position shown represents the final equilibrate state with the assumptions that the angles and the length of the ropes remain constant, thus no change in the shape of either triangle (see sketch below).
If this is the case, then you can solve the question simply by engineering mechanics, $\sum F_x = 0$ (since the apex will not move), and $\sum F_y = 0$), that is:
$T_A cos\theta_A = T_B cos\theta_B$, and $T_A sin\theta_A + T_B sin\theta_B = T$
However, if the assumption are not true, then you need to take into account of the deformation of the ropes (geometry changes) as shown on the sketch. The equilibrium equations remain the same but with the terms having a superscription "$'$" - $T_A cos\theta_A' = T_B cos\theta_B'$, and $T_A sin\theta_A' + T_B sin\theta_B' = T$, and with an additional assumption, that for change of angle is small, the distances of points $A$ - $C$, and $C$ - $B$ are approximately constant before and after the stretches due to the applied load.
Comment: I'm curious what software was used to create this sketch?
Comment: #MeToo 87654321
Comment: Using any graphic program such as cad. This one was using Openoffice's drawing tool.
Comment: Some alternatives: Paint.net (bitmaps with layers), Geogebra (used in schools), Tikz (hardly anything you can't visualize with it).
Answer: Here's a new answer to an old question.
Oversimplification
Assuming $10° \approx 20° \approx 0°$, the forces $F_A$ and $F_B$ in both ropes are equal as both ropes are in parallel, hence $5$ N each. However, this oversimplification will not hold: it's just a limiting case.
Calculations
The diagram shows the ropes in its lower part (black) and the force-vectors in its upper part (red). We can derive two equations from it in two variables, which we can solve.
For the resultant in y-direction we have:
$F_A \cdot \cos(10°) + F_B \cdot \cos(20°) = 10 N$
While in x-direction (vector $\vec F_c$) this equality must hold:
$F_A \cdot \sin(10°) = F_B \cdot \sin(20°)$
or
$F_B = F_A \cdot \frac{\sin(10°)}{\sin(20°)}$
which yields by substitution
$F_A \cdot \cos(10°) + F_A \cdot \frac{\sin(10°)}{\sin(20°)} \cdot \cos(20°) = 10 N$
or
$F_A  = 10 N \cdot \frac{1}{\cos(10°) + \frac{\sin(10°)}{\tan(20°)}} = 6.8 N$
As can be seen easily, e.g. by Taylor approximation, the fraction approaches $\frac{1}{2}$ when both angles approach $0°$, as we noted in the oversimplification ($\cos(x) \approx1$, $\sin(x) \approx x$, $\tan(x) \approx x$, [$x$] = 1 rad, $x \rightarrow 0$).

(done by tikz)

Calculating two diagonal forces


Mazda 3 (2008) coolant leak, only when starting the engine

Question: I have a 2008 Mazda 3. Since I got it (about 2 years ago) it is loosing coolant fluid constantly (and it is getting worst: now I fill in a liter of fluid a day). The mechanics in the garage can't find a leak, but they replaces the container, the thermostat, and more. Lately, I noticed that the leak happens when I start my car. Not while driving or Idling, only while starting. Any Idea what could cause such a thing?
Answer: To identify the cause of a coolant leak, there are 2 general options:

clean the crap out of your engine bay, make it squeaky clean so that you can SEE where fluid is leaking from
add an ultraviolet dye to your coolant, and after running the engine (or starting it, in your case), go over the engine bay with a black light

Common causes for coolant leaks are:

worn out water pump or water pump gasket (look at the pump while the engine is starting or running, inspect your belts for coolant while the engine is off)
loose hoses (personally, I replace the snap rings that come from the factory with screw-tight hose clamps, the kind you would use to fix your garden hose, picture below)
cracked radiator (look at it from all sides, look for stains)
some engines have coolant passages in the timing cover, if the rubber o-rings rot, you will have a leak in there. On most engines, this is a lot of work (a lot of disassembly). Depending on the specific engine design, the coolant may leak into your motor oil or leak out of the edges of the timing cover.
Answer: There's only 2 places missing coolant can go:

outside (you would have found a puddle, or at least some stain marks)
inside the engine (burning coolant turns your exhaust white)
Comment: Right.. the fluid goes outside, but only when starting the engine. what do you think is the cause?


Does the Sun have any atmosphere?

Question: Does the Sun have any atmosphere of its own? Is it just like the atmospheres that the planets have.
Comment: It does, but it's not a planet. Note also that some planets have no atmospheres, or at least have extremely dilute atmospheres.
Comment: Could we say the corona is some kind of atmosphere? Or just lets call it Sun's corona.
Comment: Like  @J.Chomel said:  first define "atmosphere" for any gaseous body
Comment: At some point between Mercury and the solar core, gas pressure reaches 1013.25 hPa. That's sea level pressure on earth. Mostly hydrogen, so you're not going to survive breathing the stuff.
Comment: Oh yes, "Stellar Atmospheres" (1970) is still in print: https://www.google.com/search?q=%22stellar+atmospheres%22+book&ie=utf-8&oe=utf-8 Looks like they're up to volume 6. -Lots of nice integrals in the first edition. They've probably gotten more complicated over the years.
Answer: Yes the Sun has an atmosphere.
Disclaimer: I'm not sure if you meant this, but your question implies the Sun is a planet. It, of course, is a star and not a planet. Just wanted to make that clear.
What is an atmosphere?
When you ask if the Sun has an atmosphere, you're actually asking a tricky question. What do you mean by atmosphere? How do you define the boundary of the Sun, above which anything is considered an atmosphere? This is pretty easy for planets like Earth since they have a nice solid surface. But the Sun is a giant ball of plasma heated to thousands of degrees. There's no easy or clear division between the "surface" and "atmosphere". Any discussion of the Sun's atmosphere involves defining what we mean by the surface of the Sun.
Optical Depth
That being said, astronomers have come up with (arbitrary) ways to define the surface of the Sun. One common metric is to use optical depth. Optical depth is a unitless number that defines one's ability to "see" through a gas (or plasma). An optical depth of 1 or higher means the gas is opaque and cannot be seen through. An optical depth less than one means the gas is transparent and can be seen through.
However, when you have something the Sun or even fog, the optical depth varies with the distance you're looking into that object. I'll talk about fog since it's familiar, but the same idea applies to the Sun's atmosphere. Say you're standing in a forrest and its very foggy out. There's a tree 1 meter away from you that you can see. You could measure your optical depth, $\tau$, of the fog between you and tree and might find that $\tau = 0.15$. Since $\tau$ is less than one, that implies you can see the tree, but the value of $\tau$ also implies how well you can see it. If $\tau = 0$, there's nothing between you and the tree to impede your ability to see it. Let's say there's another tree that's 5 meters away. Now there's more fog between you and the tree and while you can still see it, it is harder to see it. The optical depth of the fog between you and the tree 5 meters away might be $\tau = 0.75$. It's still less than one, implying the tree is visible, but because there's more fog between you and the tree, the optical depth is higher. Finally, there may be a tree 10 meters away with so much fog between you and the tree that the optical depth is $\tau = 1.5$. You can't see this tree because there's too much fog in the way. Hopefully you now realize that anything which is at a distance where $\tau > 1$ is not visible to you. That effectively defines a "surface" around you precisely when $\tau = 1$. Anything beyond that point is not visible and anything closer is visible.
If you're talking about the Sun, you can look at the Sun, but you'll only see light which originates from a point where $\tau < 1$. There are countless photons bouncing around inside the Sun, but you can't see them because they're in an opaque part of the Sun. Astronomers use the optical depth as a metric for defining the "surface" of the Sun.
Keep in mind the above description is highly simplified, almost to the point of being wrong. The optical depth is a useful metric for defining a surface, but it doesn't imply there's an exact radius for the surface or even that the surface is constant for every wavelength. There are a lot of other factors that make this much more complicated than I'm describing here. Hopefully you get the general idea though.
The Sun's atmosphere
For the Sun, the atmosphere would be anything above the surface. Nominally the surface is defined as the point where the $\tau = 2/3$ (despite what I said above, and for reasons I won't go into here). The atmosphere above this surface is complicated and difficult to study. The atmosphere, just above the surface, is violent, turbulent, filled with outbursts and magnetic fields, and extremely hot. Below are some pictures of this region of the atmosphere.

 Left: Image of the corona during a solar eclipse. Right: Image of the corona from SOHO. An occulting mask has been placed over the Sun.
The atmosphere of the Sun extends far beyond that though. In fact, Earth is currently moving through the Sun's atmosphere. It's very tenuous out near Earth, but still exists. The Sun's atmosphere hitting our planet is the reason for aurora. Beyond the lower portions, the atmosphere is generally referred to as the Solar Wind. This solar wind actually extends far out, beyond Pluto even. Exactly how far is difficult to define, but estimates place our Sun's atmosphere extending out to about $\sim230\:\mathrm{AU}$. At that point is the bow shock, where our Sun's atmosphere slams into the interstellar medium surrounding us.
Our own Sun's atmosphere is hard to study on a large scale since we're inside it, but we have been able to observe this bow shock around other stars, as shown below.

LL Orionis bow shock in Orion nebula. The star's atmosphere collides with the nebula flow. Hubble, 1995
Comment: @warrick I know a few solar astronomers who would disagree with you about the solar wind not being part of the atmosphere :) As for being gravitationally bound, most solar wind is ~400 km/s while the escape velocity is ~600 km/s. There is "fast solar wind" in the 700-800 km/s range, but that loses its steam once it hits the bow shock and becomes gravitationally bound anyway.
Comment: +1 Great answer: explains how we define the surface of the Sun, which is important for defining the atmosphere. That said, I personally think it's a bit of a stretch to call the solar wind part of the atmosphere because AFAIK the particles aren't gravitationally bound to the Sun. Also, for the record, the layers below the surface are also turbulent, violent, and difficult to study. ;)
Comment: I stand corrected! :)
Comment: An example of a low-quality question spawning a high-quality answer. I learned more than I expected to!
Comment: @zephyr, Thanks for the answer.. I think you have got some misunderstanding here. Question didn't mean that Sun is a planet. But what It meant to was, "atmosphere like other planets".

Does the Sun have any atmosphere?


Why is the speed of sound in air constant (relative to temperature) when the wave speed formula is Vwave = fλ?

Question: By the logic of the wave speed equation, shouldn't a 1000 Hz sound travel twice as fast as a 500 Hz sound? I know it doesn't, but why not?
Answer: as frequency goes up, wavelength goes down. their product is constant.
Answer: Think of time scales.
There is the time scale for something to change (eg pressure) in a localised region of a gas which is related to the frequency of the wave, eg frequency of oscillation of a loudspeaker cone.
There is the time scale for the information as to what is happening in one localised region to reach another localised region which has something to do with the speed of molecules as the only way that (ideal) gas molecules can communicate with one another is via collisions.
These two time scales are independent of one another ie frequency of oscillation in one localised region does not affect the speed at which information (wave speed) moves from one localised region to another localised region.
What the frequency does change is where in space the pressure of one localised region is $2\pi, 4\pi$ etc out of phase with another localised region and the distance between two such localised regions is an integer times a wavelength.
If the frequency increases the distance between such localize regions (wavelength) changes in inverse proportion.
It can be shown that the product of the frequency and wavelength is constant - the speed of the wave.


Are lord Ganesh ,Lord Subramanya Swamy and Lord Ayyappa are gods or demigods according to bhagavad geeta

Question: Are lord Ganesh , lord subramanya Swamy and lord Ayyappa are gods are demigods according to bhagavad gita
Comment: Gita does not address your question.
Comment: Gita does not mention all of them by name. It does mention Skanda (subramanya) as sena pati of devas, so yes he would be a devata (demigod).
Comment: The definition of demi God is **having lesser divine status**.  It is Puranic concept.  In BG, Ganapati and Ayyappa were not mentioned.  Shiva, Vishnu, Skanda were mentioned as the greatest among respective groups.(10th chapter)
Comment: If deva means demi god than in b.g. itself, krishna described himself as a deva. I think 3 times. So, i guess, that's it. So, its depends upon the definition of demi god which is a greek term n according to them all avatars, plus children of immortal with mortals like karna, pandava, bhishma, etc are demi gods. Prd.. As in vedas except Rudra every one else are addressed as devas only. So, a deva means god only. The most common example is the word Tridevas. ..
Answer: As explained in the comments from other users, Srimada Bhagvada Gita doesn't deal with the question asked.
Only god Kartikeya (Subramanyam Swamy, Skanda, Murugan, Shanmugha) is mentioned in the Gita in the Chapter on Vibhūti Yoga.

Srimad Bhagvad Gita Chapter 10, Verse 24
पुरोधसां च मुख्यं मां विद्धि पार्थ बृहस्पतिम् । सेनानीनामहं स्कन्द:
सरसामस्मि सागर: ॥ 24 ॥

O son of Prtha, know me to be Brhaspati, the foremost among the priests of kings. Among comanders of armies I am Skanda; among large
expanses of water I am the sea.

English Translation by Swami Gambhirananda

Krishna count Skanda as his one the best of the Vibhūtis (opulences).
Besides that,
There's no explicit mention of the gods - Kartikeya or Ganesha or Ayappa, in the Gita.
So, the answer is Srimada Bhagvada Gita Gita doesn't dwell on the God or demi-god status of any god.
Certainly, since it's spoken by Sri Krishna, several sects consider him to be the Supreme God in the text.
Besides that, your question cannot be answered from Bhagvad Gita.


electricity no power in 3 outlets located in my living room

Question: I have 3 outlets that are not working. When I use a meter and it reads red to the left and yellow far right? I checked the circuit breaker and it's not tripped? I don't have a GFCI outlet, just standard outlets. When I plug my lamp in I get no power or anything. I still have all power in the entire rest of the house. I continue to switch breakers off and on in the panel still nothing happens. Can anyone tell me what is wrong?
Comment: Does _"red to the left and yellow far right"_ mean the readout on a [receptacle tester](http://www.idealindustries.ca/products/test_measurement/electrical_testers/receptable_testers.php)?
Answer: It is most likely a bad connection in a receptacle somewhere in the circuit. The problem is almost certainly in the first dead receptacle or the last working one if the circuit is wired in a typical modern fashion (wired one to the next).
I have no idea what you mean by "i use a meter and it reads red to the left and yellow far right?", but you need to check for voltage to the circuit neutral. It is also possible for the hot (live) side to be connected, but the neutral to be open, which will give you a live reading but the circuit itself will still show as dead.


Inverse Laplace transform of $\frac{\log(s)}{1 + s}$

Question: Is it possible to find the inverse laplace transform $$\mathcal{L}^{-1}\frac{\log(s)}{1 + s}$$ using the Bromwich integral formula $$\mathcal{L}^{-1} \{F(s)\}(t) = f(t) = \frac{1}{2\pi i}\lim_{T\to\infty}\int_{\gamma-iT}^{\gamma+iT}e^{st}F(s)\,ds$$  I'm having trouble coming up with a suitable contour to use.  If the denominator were $1 - s$, then the pole would be in the right hand plane and the residue theorem would reduce the integral to the sum of the residues plus the integral around the branch cut.  But with this one, the pole is in the left hand plane where the branch cut should be.  Instead of setting $\gamma = 1$ as it must be in the case where the denominator is $1 - s$, can I set $\gamma = 0$, run the contour down the real axis and detour around the origin? I'm not sure if this is allowed, or will work.  Thanks for any advice.
Comment: You should be able to let the cut be the ray from the origin to $e^{i(\pi + \epsilon)}\infty$, for example, so you end up with an integral around the pole at $s=-1$ and another around the cut.
Answer: The result below assumes $t>0$ (as usual for Laplace transforms).
In the Bromwich contour $\gamma$ has to be chosen large enough that it is to the right of all singularities (poles and branch points) so $\gamma = 0^+$ is perfectly valid. The singularities of $\log s/(1+s)$ are a pole at $s=-1$ and two branch points at $s=0$ and $s=\infty$ which we connect via a branch cut along the negative real line.
Then we can deform the contour further to a path which starts at $-\infty -i 0^+$. Runs along the negative real line just below the branch cut. Ends at $0-i 0^+$ in a little semi-circle and then runs back from $0+i 0^+$ to $-\infty +i0^+$ just above the branch cut.
The Bromwich integral thus is given by
$$f(t)=\frac1{2\pi i} \int_{-\infty}^0\!dx\, \left(
\frac{\log (x-i0^+)}{1+x-i0^+ } - \frac{\log (x+i0^+)}{1+x+i0^+ } \right) e^{x t} $$
as the small circle around the branch point at $0$ does not contribute ($|z|\log z  \to 0$ for $|z|\to0$).
In the remaining integral, we use $\log(x \pm i 0^+) = \log |x| \pm i \pi$ valid for $x<0$:
$$\begin{align} f(t) &= \frac1{2\pi i} \int_{-\infty}^0\!dx\, \left(
\frac{\log |x|-i\pi}{1+x-i0^+ } - \frac{\log |x|+i\pi}{1+x+i0^+} \right) e^{x t}\\
&= \frac1{2\pi i} \overbrace{\int_{-\infty}^0\!dx\, \log |x| \underbrace{\left(
\frac1{1+x-i0^+ } - \frac1{1+x+i0^+}\right)}_{2\pi i \delta(x+1)}  e^{x t}}^{=0}\\
&\quad -\frac12 \int_{-\infty}^0\!dx \underbrace{\left(
\frac1{1+x-i0^+ } + \frac1{1+x+i0^+}\right)}_{2\mathcal{P}\,(1+x)^{-1}} e^{x t} \\
&= -\int_{-\infty}^0\!dx \,\mathcal{P} \frac{e^{x t}}{1+x}
=- e^{-t} \int_{-\infty}^t\!ds \,\mathcal{P} \frac{e^{s}}{s}\\
&=- e^{-t} \mathop{\rm Ei}(t)
\end{align}$$
with $s=(1+x)t$ and Ei the exponential integral.
Comment: @oen: thanks. Of course once one knows the solution there are simpler ways to obtain it (e.g., it is much simpler to check that it is the right result than to obtain it in the first place).
Comment: Nice work. (+1)
Comment: @Dr.MV: for $t<0$ the inverse Laplace transform is 0.
Comment: @Dr. MV: how do you come to this conclusion. Note that the OP has defined the inverse Laplace transform via the Bromvich integral formula and that integral for sure exists for $t<0$.
Answer: $$ f(t)=\mathcal{L}^{-1} \left[ \frac{\log(s)}{s+1}  \right]$$
$$ f(f) \space \underleftrightarrow{\mathcal{L}} \space F(s) \hspace{10mm} e^{-at}f(t)  \space \underleftrightarrow{\mathcal{L}} \space  \frac{\log(s)}{s+1} $$
$$ e^{t}f(t)=\mathcal{L}^{-1} \left[ \frac{\log(s-1)}{s}  \right] \hspace{10mm} \frac{1}{s} \triangleq  \int_0^t $$
$$ e^tf(t)=\int_0^t \mathcal{L^{-1}} \left[ \log(s-1) \right] d \tau \hspace{10mm} -t.f(t) \space \underleftrightarrow{\mathcal{L}} \space \frac{d}{ds}F(s)$$
$$G(s=)\mathcal{L^{-1}} \left[ \log(s-1) \right] \rightarrow -t.g(t)=\mathcal{L} \left[ \frac{1}{s-1} \right] \rightarrow g(t)=\frac{-e^t}{t}$$
$$f(t)=e^{-t} \int_0^t \frac{-e^{\tau}}{\tau} d \tau = \int_0^t \frac{-e^{-(t-\tau)}}{\tau} d \tau$$
Comment: Something is wrong here, the last integral doesn't converge.


Why is the Oort cloud spherical?

Question: Having read up a bit about the Oort cloud hypothesis, I find I don't quite understand this. Why is the Oort cloud spherical while the rest of the solar system is disk-shaped?
Comment: The better question may be: Is the Oort could spherical?  It assumes less and is less likely to be proven to be a poor question if it turns out that the Oort cloud is actually quite distorted by interactions much of the time. Having said that, I don't know if that is the case or not... just trying to give food for thought for what may be a really exciting scientific question that may take a lifetime of work to answer.
Comment: From Wikipedia: `Gravitational interaction with nearby stars and galactic tides modified cometary orbits to make them more circular. This explains the nearly spherical shape of the outer Oort cloud.[3] On the other hand, the Hills cloud, which is bound more strongly to the Sun, has yet to acquire a spherical shape.`
Comment: Objects inside Neptune's orbit have had the opportunity to interact with other objects many, many times.  Orbits that are not circular or in-plane have a greater chance of interactions that modify the orbit.  Over time, such orbits are eliminated.  The Oort cloud is so sparse and speeds slow that interactions between objects are minimal and other orbits can persist for long periods.
Answer: I actually answered a related question a couple of days ago on Astronomy. Small world!
One of the important properties of the Oort Cloud is that objects in it are not strongly influenced by the Sun. After all, its inner edge is roughly 2,000 AU away - 300 billion kilometers from the Sun. The Sun's gravitational influence in that region is rather weak, so the Cloud can be easily subjected to other effects.
Galactic Tides
The first big effect (which stackErr mentioned) is the galactic tide. Tidal forces can stretch an object into different shapes. As Wikipedia puts it,

Galactic tides may then deform an otherwise spherical Oort cloud, stretching the cloud in the direction of the galactic centre and compressing it along the other two axes, just as the Earth distends in response to the gravity of the Moon.

So any disk-shaped object this size this far away from the Sun would inevitably become stretched out into an oblong or spherical shape.
Nearby Stars
The outer limits of the Oort Cloud may be over 1 light-year away. By comparison, the distance to the nearest star system (Alpha Centauri A/B and Proxima Centauri) is roughly 4 light-years. Once again, the weakness of the Sun's gravity means it is easier for the Cloud to be deformed. Passing stars long ago could have contributed to its shape.
As this picture shows,

Stars can and will come closer than that - just within the next 80 millennia! Within the past 4 billion years, odds are that we've had a lot more closer encounters. So any stars within a light-year or so would have had a pretty big impact on the Cloud.
Also, some of the bodies in the Oort Cloud may have originated in other star systems, or from somewhere completely different. Interstellar comets and Exocomets could have been captured by the Sun. This would mean that they wouldn't have to have orbits in the plane of the rest of the solar system - they could travel in orbits tilted at odd angles.
Comment: It is also highly probable that the Sun was once part of a much denser cluster of stars. Close encounters would have been much more common.
Comment: The graph really helps. I didn't have a sense of the distances involved, I had no idea that there were points in time where the Oort cloud's radius could be nearly a third of the distance to the nearest star. That makes the tidal forces explanation much clearer.

Why is the Oort cloud spherical?


Using GDAL in Python to Convert NetCDF to ASCII and flip latitudes

Question: I have a NetCDF file containing bathymetry. I am using the GDAL and NETCDF4 libraries to export the file to ESRI ASCII using the 'AAIGrid' format. However, a common problem is the latitudes are in the reverse order (see here for patch made to gdal and here for Matlab and here for R solutions).
I think the solution can be achieved using Numpy and flipud function. I am not sure whether to flip the bathymetry or the latitude. When plotting using matplotlib, both seem to work to fix the problem.
I seem to be encountering two problems. First, when using gdal.Translate, the output Dataset cannot be passed as the NetCDF4 'Dataset' object - it must be a file. I would like to pass it a Dataset object which I have modified by flipping the latitudes. When I pass in an object (even an unmodified Dataset object which just references the original .nc file), I get the following error:
<code>#gdal.Translate("out.txt", "test4.nc", format="AAIGrid", noData="-10")
gdal.Translate("out.txt", new_netcdf, format="AAIGrid", noData="-10")

    TypeError: in method 'TranslateInternal', argument 2 of type 'GDALDatasetShadow *'
</code>
Second, I cannot seem to flip the latitudes by modifying the original file.
<code>from netCDF4 import Dataset
from osgeo import gdal
import numpy as np

file = "ORIGINAL\Bathymetry_1km.nc"
netcdf_f = Dataset(file, "r", format="NETCDF4")

latitudes = netcdf_f.variables['lat']
lat_flipped = np.flipud(latitudes)
netcdf_f.variables['lat'][:] = lat_flipped

---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
<ipython-input-126-457cda137417> in <module>
----> 1 netcdf_f.variables['lat'][:] = lat_flipped
netCDF4\_netCDF4.pyx in netCDF4._netCDF4.Variable.__setitem__()
netCDF4\_netCDF4.pyx in netCDF4._netCDF4.Variable._put()
netCDF4\_netCDF4.pyx in netCDF4._netCDF4._ensure_nc_success()
RuntimeError: NetCDF: HDF error
</code>
So, next I create a new NetCDF 'Dataset' object (actually as a file on the drive because I can't figure out an alternative) and populate it with the lats, lons, and bathy dimensions / variables from the original dataset. That seems to work except when I go to translate it to ASCII, I end up with a grid full of 9.9692099683868690468e+36 and nothing else.
Comment: flipped in what way?
Answer: Esri ArcGIS can read netCDF files directly. No need to convert to ascii.
Comment: I'm not reading the ASCII files into ArcGIS


How to insert an HTML table in Google Calendar's description

Question: How can I insert a rich text table into a Google calendar event so that the invitees do not have to worry about tabs or fonts?
Answer: Google Calendar description text is sent to email clients with little to no modification. Convert the rich text table to HTML tags if you can safely assume the invitees have rich text email clients.


Do HIPAA Security Officers face personal liability for breaches?

Question: The role of HIPAA Security Officer is very important in maintaining compliance. In smaller organizations, there's overlap in employees' roles, so the person that ends up as the HIPAA Security Officer may not have a whole lot of background in compliance. Does the individual serving in this role face more personal liability for breaches than other employees?
Answer: Good question! But there's not a solid answer I'm afraid. As with most of these cases, it depends case by case, but there are a few things to consider.
First of all if there has been some for of negligence than an individual can be personally liable.
However I don't think that an HIPAA Security officer is any different than any other person responsible for the security of sensitive personal information; usually these cases don't make it to court.
Comment: @JohnStraka Professional liability from a company officer usually requires inappropriate ignorance of conditions or malice. If you made the best reasonable efforts, you ought to be in a sound position.
Comment: Asked our company's lawyer and pretty much got the same answer. Though I admit "I can tell you that it hasn't happened yet" wasn't as reassuring as I'd hoped.
Comment: Any update to this? Anyone know of any cases where Security Officer was held personally liable?
Answer:
Does the individual serving in this role face more personal liability for breaches than other employees?

Disclaimer: I am not a lawyer, but I have been through several rounds of HIPAA training.
Is a HIPAA security officer automatically liable for a breach?  No.   If the security officer has done due diligence, the proper safeguards are in place, and some malicious user goes and sells a celebrity's health information to a paparazzi anyway, it seems doubtful that the security officer would be named in any resulting lawsuit. Even if they were named, they've done their job and should have nothing to fear.
But is a HIPAA security officer exposing him/herself to more potential liability than the average employee?  Maybe.  By taking on the responsibility for this area, it's possible that they might face some form of liability if they are negligent in the safeguards they put into place or the training of others.  (Though as @John Straka pointed out, I've never heard of it happening.)
Answer: Unfortunately, I think the question is currently moot.  While I think HIPAA compliance is important, enforcement is still non-existent.

Franken noted dryly that 64,000 privacy complaints have been filed with the OCR—and that nearly 500 were referred to the Justice Department for criminal investigation. But the Justice Department told his staff, Franken said, there have been just 16 HIPAA criminal prosecutions. Meanwhile, HHS had secured only one civil monetary penalty and six settlements, he said.

http://www.modernhealthcare.com/article/20111116/BLOGS02/311169962/candid-comments-on-hipaa-privacy-rules-enforcement
Until enforcement changes occur, we won't know who will really end up being responsible.


Fantasy novel where guy fights with a cloak on his back

Question: There was a novel I read back in the 90s (I'm pretty sure) about a guy who fought using a weighted cloak or cape. There's very little I remember about it beyond that. He didn't take the cloak off in the cloak-and-dagger style, but rather used it kind of like a whip from his back and shoulders. Anyone ever heard of it?
Comment: If you haven't already, can I suggest you take a look at [this guide](https://scifi.meta.stackexchange.com/a/9337/68872) and see if you can [edit] in any more details
Comment: This sounds like The Shattered World by Michael Reaves. Some google searching reveals that one character is a cape/cloak fighter who has blades woven into his cloak. The book was published in 1985.

https://www.amazon.com/Shattered-World-Michael-Reaves/dp/0671559516
Comment: Thanks @just_happen_to_know I'm buying the book now and will update if it's what I'm looking for
Comment: possibly the same as https://scifi.stackexchange.com/questions/108472/looking-for-title-and-author-fantasy-shapeshifting-thief-sorceress
Comment: @just_happen_to_know: If you put your suggestion as an answer rather than just as a comment, then he can choose it as correct if it turns out to be right, and you will get points for it.
Comment: @just_happen_to_know appears to be correct, btw. Happy to mark it as correct.
Answer: If just_happen_to_know comes back, I'll yield the answer, but The Shattered World by Michael Reaves was identified in the comments and confirmed there was well.

A thousand years ago, the world was broken in a great cataclysm; now people live on the fragments, flying between them in ships made of the skin & bone of dragons. The book follows the interweaving stories of a thief, a couple of wizards, and various others as events are set in motion that will take them on perilous journeys to the far reaches of the world with far-reaching consequences.

The "cloakfighter" is named Kan Konar.
There's a sequel with some of the characters including Kan Konar called The Burning Realm.


Epson L210 printer

Question: Few weeks ago I bought this printer but only yesterday I unboxed it and start testing it. The problem comes when I want to print something. Firstly, it printed out a blank page. So I thought of giving it a try couple of times just to make sure the ink reached the printer head. After 3 hours trying finally some ink came out. The only color that came out is magenta and yellow. The blue and blank ink is yet to be seen. What can I do to solve this problem? I already tried for head cleaning. Only God knows how many time I did it. Please help.
Comment: It shouldn't do that.  Since it's new, I would contact the seller for an exchange.
Answer: As fixer1234 said, contact the seller and exchange it.
If you want to test the ink, get a piece of tissue, scrunch it up, stick it next to the nozzles and shake hard...
If you don't see anything, it is possible the cartridge is dried up.
If you do see some colour, it is actually worse as most likely the printer heads are jammed.
In the first case - easy to solve/get a new cartridge. In the second case, it can be a big support issue that isn't always worth the price to fix, so, if you have a warranty - use that.

Epson L210 printer


Textbook explanation of the resonant frequencies of molecules

Question: An online source stated that molecules have resonant frequencies and then vaguely said that university textbooks should be consulted for more information. Another source contradicted the first in regard to the relationship between microwave absorption and molecular resonance. However I am not interested so much in microwave absorption as in molecular resonance frequencies. What is a good textbook for understanding the resonant frequencies of molecules?
Comment: Maybe add the resource recommendations tag, increase your chances of an answer, regards
Comment: "Textbook explanation of the resonance frequencies of molecules" is not a question, so there's no need to put a question mark at the end. I removed it. Also, the original title had lots of capitalized words for some reason so I fixed that too. Take a look at [this meta post](http://meta.physics.stackexchange.com/questions/6413/how-do-we-write-good-question-titles) for tips on writing good titles.
Answer: Most any quantum mechanics textbook will discuss molecular resonances.
The classic book on molecular resonant frequencies is Spectra of diatomic molecules by Gerhard Herzberg.  For larger molecules, you will want to consult Infrared and Raman spectra of polyatomic molecules, also by G. Herzberg.
As for the microwave issue, the second link that you cite, cyberphysics, confusingly writes:

Some science books say that the frequency of microwaves used in a
  microwave oven is the 'natural frequecy' of water and resonance is the
  mechanism that causes the vibration. That is not the case - it is down
  to the pull of the electric and magnetic forces from the wave.

They are dealing with two halves of the same coin: microwaves do excite molecular resonances and they do that through "pull of the electric and magnetic forces" (with electric forces being the most important).  So, both are true.
Separately, in the gas phase, molecular resonances are very sharp.  In liquid phase, like water in a microwave, they are less sharp.  As they become less and less sharp, some might choose to stop using the word resonance.


How much time was spent between when Lowell exited Saturn's rings and when he was discovered?

Question: In the sci-fi film Silent Running, botanist Freeman Lowell pilots his ship, the Valley Forge, through the rings of Saturn and isolates himself from other humans for a long time. Eventually, he is found by the ship called the Berkshire. It is unclear to me how much time he spent alone. How much time is there between when he exits the rings of Saturn and when he is found?
Answer: The film's official novelisation (based on the original screenplay) indicates that the order to jettison and auto-destruct the domes was given on the 14th of November. This occurs shortly before the crew suffer their "accident" and the ship tumbles through Saturn's rings.

A clock/calendar on the wall read: 21:00 Wednesday 14 November
All at once the radio filled the room with whistling, howling static
  which finally gave way to a very distant-sounding voice . . . Lowell
  tried to tune it in, but Barker took over.

The next time we see a clock it's just before the Berkshire arrives on the 8th of April, some 5 months later.

Lowell's laughter went on and on. It was uncontrolled and hysterical
  amidst his loneliness with only the companionship of the unfeeling
  drones. His eyes watered and his lips trembled and his laughter filled
  the recreation room and spilled out over the bronzed hull of Valley
  Forge, drifting through space under a sea of stars.
At last Lowell fled from the recreation room to the corridor and then
  to his room. He flopped on his cot . . .
Above his bed, on a shelf, a calendar clock read: 04:02 Tuesday 8
  April.
Comment: If 14 November is a Wednesday, then 8 April of the next year falls on a Monday, not a Tuesday. Oh wait, leap years.


A Smudging Lemma in Lattice

Question: I saw a paper LLW21 in EUROCRYPT 2021 that used this lemma, but there was no proof or references.
How should this lemma be proved ?
Answer: In general the total variation distance (what you call the statistical distance --- both names are used) between (even continuous!) Gaussians is hard to compute.
See for example this.
Instead, people often instead compute a different measure of distance between Gaussians, and then use this quantity to bound the total variation distance.
Specifically, in terms of the KL divergence, the bound
$$\Delta(P, Q) \leq \sqrt{\frac{1}{2}\mathsf{KL}(P||Q)}$$
is known as Pinsker's inequality, where $\Delta(P, Q) := \frac{1}{2}\lVert P-Q\rVert_1$ is the Total Variation distance.
Throughout, I will write $P$ for the distribution with pmf proportional to $\exp(-\pi \lVert\vec x\rVert_2^2/\sigma^2)$, and $Q$ for the distribution with pmf proportional to $\exp(-\pi \lVert \vec x-\vec c\rVert_2^2/\sigma^2)$.
I'll write the proportionality constants as $C_P$ and $C_Q$.
Anyway, one can compute that
$$\mathsf{KL}(P||Q) = \sum_{\vec x}P(\vec x)\left(\frac{\pi \lVert \vec c\rVert_2^2}{\sigma^2}-2\langle\vec x,\vec c\rangle\right) + \ln(C_P/C_Q)$$
By considering pairs of points $\vec x, -\vec x$ (where $P(\vec x) = P(-\vec x)$), one can see that the $-2\langle\vec x,\vec c\rangle$ term will cancel (it doesn't for the total variation distance, and is the reason why bounding it directly is annoying).
For the proportionality constants, it is known (Lemma 2.7) that $C_P \leq C_Q$, under your condition that $\sigma \geq \omega(\sqrt{\log n})$.
Applying Pinsker's inequality, and we get
$$
\Delta(P, Q) \leq \sqrt{\frac{\pi}{2}}\frac{\lVert \vec c\rVert_2}{\sigma}.
$$
Note that this constant may be an artifact of my normalization of Gaussians.
If you use the alternative normalization $\exp(-\lVert \vec x\rVert_2^2/(2\sigma^2))$ that some authors prefer, you get the bound
$$\Delta(P, Q) \leq \frac{1}{2}\frac{\lVert \vec c\rVert_2}{\sigma}$$
I won't check which normalization your paper uses, as either way I imagine the above is good enough for you.
Answer: You probably should define $\mathsf{SD}$ and $\mathcal{D}$.
There is a much simpler 1-dimensional version that is proved, see Lemma 2.1 of Asharov-Jain-Wichs, 2011.
The proof is one-line:

In [LLW21], $\mathcal{D}$ denotes $n$-dimensional discrete Gaussian.
I did not find a proof, but there is another similar lemma with proof (which I did not read):
https://eprint.iacr.org/2022/055.pdf
Comment: The smudging lemma of 2022/055 is different. It is bounding the distance between a sub-set sum of Gaussians and that same distribution plus some independent gaussian noise. In particular, all gaussians are centered in it.

A Smudging Lemma in Lattice


frame animation window not appearing?

Question: i'll do my best since english isn't my native language
long story short i need to animate  a .gif file and i need the video frame editor. for that i used to click this one button pointed with the arrow but it doesn't appear anymore and i don't know why or how and I NEED IT
Comment: Is this Photoshop?
Comment: @Jongware this is Sparta!
Answer: Photoshop CS6 was the first version to default to a timeline animation. If you want a frame animation, you can convert to frames by using the menu on the Timeline Panel.
Answer: In short, here's the solution. In Photoshop cs6 click on;
Window > Extensions > Mini Bridge - it shows Timeline - then click on Create Frame Animation.
It may be June 2018 but I hope this helps someone. I am still on CS6 which does not have the 3D features (sorry, can't help you with that) or the same Animation set-up... or does it?
I thought I would have to either go backwards or forwards to continue Photoshop animation UNTIL I found the solution. A lot of people have asked where the Animation window is & then been advised you need the Photoshop Extended version... BUT you don't. (Although, apparently, you do for the 3D features).
Adobe have put it in an inconspicuous place. Not sure why, maybe there's a reason... maybe not?  @_@   Cheers all - Happy Creating!

frame animation window not appearing?


TLS downgrade attacks

Question: I'm currently looking at e-mail security and wondered whether server to server e-mail communication that enforces TLS, will prevent the risk of TLS downgrade attacks?
Comment: Are you really asking about downgrade to a weaker TLS version (unlikely to succeed in most cases) or more about downgrading from TLS to plain by a MITM stripping support for STARTTLS?
Answer: TLS Downgrade attacks consist of a MITM threat actor forcing the weaker TLS/SSL protocols because the server permits the weaker protocols. Server-to-Server is still possible but client-to-server is the most likely.
A good candidate for an attackers success:
In this scenario, the attacker in the simplest form, drops the packets of the victim requesting the higher protocols, thus the downgrade attack, then the client retries lower protocols. This downgrade gives the attacker a high probability of being able to acquire session cookies, modify traffic, steal credentials, intercept emails, etc.
Victim   - Supports SSL 2.0, 3.0: TLS v1.0, v1.1, v1.2, v1.3
         - Supports High, Medium, Weak, CBC, and Null Ciphers
Attacker - Has Successful MITM
Server   - Supports SSL 2.0, 3.0: TLS v1.0, v1.1, v1.2, v1.3
         - Supports High, Medium, Null Ciphers

A good candidate for an admin's success:
In this scenario, the attacker can attempt to try and modify the negotiations but the server is hard set, use high protocols and ciphers, or nothing. The attacker really has no chance to decrypt the communications. Or at least not yet... Computers in 5-10 years will be different and these protocols will become outdated. IETF already has a draft for decommission of TLS v1.1.
Victim   - Supports SSL 2.0, 3.0: TLS v1.0, v1.1, v1.2, v1.3
         - Supports High, Medium, Weak, CBC, and Null Ciphers
Attacker - Has Successful MITM
Server   - Supports TLS v1.1, v1.2, v1.3 or just TLS v1.2 & v1.3
         - Supports High Ciphers only

Answer: There are actually two problems with SMTP over SSL/TLS via STARTTLS:

The STARTTLS downgrade problem.  Let's suppose that the receiving MTA supports STARTTLS, and advertises that it does so in the EHLO banner.  An MITM can simply strip the STARTTLS advertisement from the banner.  Then the sending MTA thinks the receiving MTA doesn't support TLS, and the session proceeds in plain text.

You might say, I'll solve this problem by only supporting SSL/TLS.  If the other side doesn't upgrade to SSL/TLS via STARTTLS, I'll abort the session.  Of course, this means that you won't be able to exchange mail with MTAs that don't support SSL/TLS, but maybe you're OK with that.  Fine, but how do you handle certificates?  That brings us to:

The certificate problem.  Let's assume my email address is firstname.lastname@example.com, and I use myemailprovider.com to host email for my domain.  So, when you do an MX lookup for mycompany.com, it resolves to mx.myemailprovider.com.  Now, you send me an email, so your outgoing SMTP server connects to my incoming MX server, mx.mysmtpprovider.com.  The two servers agree to upgrade the connection to SSL/TLS by way of STARTTLS.  Then, what certificate should your outgoing SMTP expect to see?  A certificate for mycompany.com?  No, that's not the way it works (in fact, it's impossible, because mx.myemailprovider.com doesn't even know the recipient of the message yet (because your outgoing SMTP server hasn't send RCPT TO yet), and mx.myemailprovider.com hosts incoming mail for many other domains in addition to mine).  The certificate that mx.myemailprovider.com presents is their certificate, for mx.myemailprovider.com.

Why is this a problem?  Well, consider a DNS poisoning attack on the sending MTA, that serves the sending MTA a false MX record for mycompany.com.  Instead of returning the correct MX record, mx.myemailprovider.com, the attacker returns mx.attackersserver.com.  Then, your sending MTA connects to mx.attackersserver.com.  mx.attackersserver.com advertises that it supports STARTTLS, so the sending MTA and mx.attackersserver.com upgrade the connection to SSL/TLS, and mx.attackersserver.com presents its own certificate (which any CA hsppily to signs, because the attackers can easily verify that they own mx.attackersserver.com, because after all, they do in fact own mx.attackersserver.com).  The sending MTA sees a valid certificate for mx.attackersserver.com, so it happily proceeds with the SMTP session, and sends the email that you intended to send to me, to the attacker.  Wonderful, right?
These problems stem from the fact that we are still using an insecure protocol (SMTP) that was developed in the 1980's, in 2019.  Supporting STARTTLS is better than nothing, but it's a bolt-on, and like many bolt-on's it can be defeated.  DNSSEC can be used to mitigate these problems to some degree, but DNSSEC also has it's own shortcomings.

TLS downgrade attacks


Arbitrary Naming Convention (Business Objects)

Question: Ok, do you do Business.Name or Business.BusinessName
SubCategory.ID or SubCategory.SubCategoryID
What about in your database?
Why?
I'm torn with both. Would love there to be a "right answer"
Answer: The only "right" answer is to be consistent.  Decide upfront which one you will be using in a project, and stick to it.
Answer: The main drawback of using ID, Name etc is that you have to qualify them with the table name if you are writing an SQL join which overlaps two tables.
Despite that, I find it far more concise and readable to just use ID and Name - your code and tables will 'flow' much more easily past the eyes. Easier to type and less redundant. And typing SELECT Business.Name FROM ... in an SQL query is not really more troublesome than typing SELECT BusinessName FROM ...
In general, if I find myself repeating semantic information it alerts me to look for ways to eliminate it or at least recognise why it repeats. This could be on the small scale (attribute names) or the large scale (behaviour patterns or common class structures).
Answer: For very common properties like "Name" and "ID", the convention I have used is to not put the entity name in the field.  For more unusual properties, I do put the entity name.
This is a naming convention decision, but I have not regretted projects where this is the convention, if you put the name of the entity for each ID, it ends up seeming to be too verbose.
Answer: we do ID on anything that's the primary key. Saying SubCategory.SubCategoryID seems redundant,
Answer: I may not be right, but I think Id is a tastier dish.
thing.id
because if you are going to write any reflective stuff that deals with your objects and needs primary key, its way easier to know it everywhere, then trying to determine it with a formula.
As for the other, thats total preference and I don't see any real implications other than time wasted typing the other characters, and its .net so no one actually types namespaces anyway.


2004 Buick Lesabre

Question: I have a 2004 Buick Lesabre. The check engine light came on so I had the code read. It was P0442. The gas cap was just sitting there so I tightened it. This has been a couple of weeks ago and the light is still on. Does this mean there is something else wrong or do I have to take it somewhere to have the light reset?
Comment: its worth a shot to try a reset.  Your local auto store can do that for you for free.
Comment: Thank you. I will try that and see is it comes back on.
Answer: You can also take the battery loose for a few minutes and that will reset it but you got to reprogram your radio stations in clock all over again that's the only sucky part about it
Answer: Once the check engine light comes on it won't go away even if the problem is fixed, you have to get it cleared. Really the only way to tell if it's fixed is to clear the code and then see if it re-occurs. You should get it reset because at the moment you wouldn't know if another fault occurred.

2004 Buick Lesabre


Do German universities consider high school grades?

Question: Do German universities consider the high school grades for post-graduate admissions since they ask for it?
Comment: It goes on like that. I had to prove being qualified for university access with the high school certificate before I was admitted for the PhD defense. Just do not think about it too much. If the grades were of any sigificance you surely would know. It would be made transparent.
Comment: Generally no - though high school grades tell you *something* about people (e.g. getting the very top grade requires hard work/discipline, while having very good grades can be achieved by being smart but lazy).
Answer: In theory there is no way to prevent them from doing so, but in general they will focus on more relevant things like bachelors degree.
The reason they ask (apart from the German love for bureaucracy) I believe is a weird quirk in German law. In order to study at a German university you need a "Hochschulreife", i.e. the qualification for university studies. This is normally gained by finishing high school.¹ It is however not gained by having a university degree, even though it is technically needed to get one in the first place. So in order to gain admission into a masters program, you both need to prove that you have the prerequisite bachelors degree, as well as the general qualification to study (i.e. have finished high school).
¹The specifics are a bit complicated, as not every type of German high-school counts. For foreign systems, I believe there are endless lists of what is equivalent and what is not, but in general this is not a high hurdle.
Comment: I'd frame it a bit more positively: It's a way of making it a bit more difficult for people who managed to get into university (or any other kind of qualification) by cheating on prerequisites to continue without ever being asked for those prerequisites.
Comment: "German love for bureaucracy" Well, not *exactly* how I would put it...
Comment: @AnonymousPhysicist Well, you have to decide *somehow* who is going to be admitted.
Comment: Odd.  In the US, finishing high school is *not* necessarily required to study at a university, and there are plenty of people walking around with PhDs who did not finish high school.
Comment: @AnonymousPhysicist Well, there is of course a long list of exceptions and about of 250 years of historical development of the system that explain why things are the way they are. But the details would be a bit far from the heart of the question.


3,000 emails from ALL MAIL are in one new label

Question: I have two new emails from someone I've not corresponded with before but will in the future.  I just made a new label for that person.  I went to settings and created a filter. Theoretically my label should only have two emails in it.  However, there are over 3,000! from my ALL MAIL. I have no idea why.  If I delete the new label, will I be deleting all 3,000 emails from ALL MAIL?
Comment: And the filter is presumably on the "From" email address? It would be easy to verify whether the 3,000 emails have the same email address. (?)
Answer: Deleting a label does not delete any emails. They will remain as they are, except will no longer have that label.
As for why you got 3,000 messages labeled, there is no way to tell.


iPhone XS not recognising (apparently) valid Development Provisioning Profile

Question: So trying to test an iPhone app on an iPhone XS.
Generally with other iPhones, I just plug in the phone, tap 'Automatically manage signing' and Xcode tells me that this device is not part of this provisioning profile. I tap repair, and that does the trick. But somehow not with iPhone XS. No 'repair' button appears.
No fear, so instead I added the device manually in developer.apple.com using the new weird shorter UDID (picked it from Xcode -> Windows -> Devices -> Identifier), regenerate the provisioning profile and download the new profile to Xcode.
Great now Xcode tells me this Profile includes my iPhone XS, but then when I try to build and run I get "A valid provisioning profile for this executable was not found."
Moreover, I cannot manually add this provisioning profile to the phone by going to Windows -> Devices and -> Provisioning Profiles -> + and choosing the new profile. => Again doing this step for an iPhone SE makes the provisioning profile appear in the list, but not for an iPhone XS.
I also tried adding the device with the SEID code, and somehow developer.apple.com allowed me to do it, but a provisioning profile with that device ID does not recognise my iPhone XS in Xcode.
I have restarted everything (phone, computer, Xcode) several times, and cleared out various cached folders and locations.
I am pretty lost on what to do next.
Thoughts good girls and boys of Stackoverflow?
Answer: OMG - 6 hours later and this was answered 4 days ago. Thanks Apple. Xcode 10: A valid provisioning profile for this executable was not found
Hack for now,


What is OTP for selecting GPIO function in PMICs?

Question: I've been going through this datasheet and I don't understand what is meant by 'OTP' for selection the function of the GPIO pins. The function select table can be found on page 20. I'm also confused why it refers to inputs and ouputs as CMOS and NMOS. Can someone explain this?
Comment: I'm going to presume OTP in this context is **One Time Programming** as opposed to Over Temperature Protection. How Ricoh implements it though I am unsure.
Comment: @JYelton it does have I2C, maybe it uses that? But I guess that wouldn't make it 'one time programming'
Comment: Maybe OTP is used to set the power-on defaults and the I2C can then change those settings if needed?
Answer: They're not referring to CMOS or NMOS, the options are CMOS or N-Channel open-drain.
The CMOS option can push or pull the pin up or down, while the open-drain option can only pull the pin down (relying on an external pull-up resistor).
OTP is almost certainly referring to One-Time-Programming.
There doesn't seem to be any indication in that document on how this programming is done though.
Comment: do you know how to do one time programming?
Comment: My guess is that the OTP is only done at the manufacturer. So you need to check which version of the IC you have. From the table, there should be somewhere in the part number you ordered to tell you how the GPIOs are configured at the factory


cakeDC utils csvImport use?

Question: I am looking to use the cakeDC CSVimport behaviour. However, I cannot work out how to set it up and there doesn't seem to be any documentation or instructions around. I am uploading a csv then I need to insert the data into the a MySQL table. I have the upload working as required.
NOTE: the csvimport behaviour is part of the cakeDC utils plugin: https://github.com/CakeDC/utils
I have this in my upload model
var $actsAs = array('Utils.CsvImport');

Within my upload controller I have this (after the file is uploaded successfully)
$this->Upload->importCSV('/maslayout/files/'. $thefilename);

I am then getting this error:
Fatal error: Uncaught exception 'RuntimeException' with message 'SplFileObject::__construct(/maslayout/files/customers_aussievets_24092010.csv) [splfileobject.--construct]: failed to open stream: No such file or directory' in E:\xampp\htdocs\maslayout\app\plugins\utils\models\behaviors\csv_import.php:105 Stack trace: #0 E:\xampp\htdocs\maslayout\app\plugins\utils\models\behaviors\csv_import.php(105): SplFileObject->__construct('/maslayout/file...', 'rb') #1 E:\xampp\htdocs\maslayout\cake\libs\model\model_behavior.php(169): CsvImportBehavior->importCSV(Object(Upload), '/maslayout/file...') #2 E:\xampp\htdocs\maslayout\cake\libs\model\model_behavior.php(467): ModelBehavior->dispatchMethod(Object(Upload), 'importCSV', Array) #3 E:\xampp\htdocs\maslayout\cake\libs\model\model.php(496): BehaviorCollection->dispatchMethod(Object(Upload), 'importCSV', Array) #4 E:\xampp\htdocs\maslayout\cake\libs\overloadable_php5.php(50): Model->call__('importCSV', Array) #5 E:\xampp\htdocs in E:\xampp\htdocs\maslayout\app\plugins\utils\models\behaviors\csv_import.php on line 105

Can you explain what I'm doing wrong?
===========================================================================
UPDATE: I worked out I simply had the path incorrect, now that I have this right it seems to be uploading however I don't really understand what to do next. I am not sure if I need to set the CSV document up somehow and how do I get the model set so the import will work and match up. Any help would be appreciated. I have it on my uploads model and this is basically insert empty rows into the uploads table. Even when I have the right headers on the form this still happens.
Answer: You may get some help on this link:
Plugin to Import CSV in CakePHPUtils Plugin for CakePHP not inserting records into table
and a complete reference is given here on GitHub:
https://github.com/CakeDC/utils

cakeDC utils csvImport use?


Running a desktop on docker containers

Question: Is it possible to run x11 server inside docker containers running on headless server. So that I could use gui applications inside them.
What I mean by that is I have a single container which is my main desktop and others which are used to run software as firefox or chrome. Much like qubes os but without spinning up a whole new vm.
Answer: It is possible to run a headless VNC server inside a Docker container.
You may download a ready-made one from
consol/ubuntu-xfce-vnc,
described as:

Ubuntu container with "headless" VNC session, Xfce4 UI and preinstalled Firefox and Chrome browser

For detailed instructions on how to build such a container, see for example
View a Docker container's display using VNC Viewer from September, 2017.
However, due to the rapid development of Docker this might not stay correct
forever.

Running a desktop on docker containers


Work in a remote terminal with Terminator

Question: I have Windows Subsystem for Linux and I would like to be able to keep some commands running even if my computer is sleeping. I have been told that one way is to work in a remote terminal. I have been told that screen does the work. But I was wondering wether Terminator was able to do it as well, as I know this tool better.
Comment: Just to be clear, the "commands to be kept running" are on a remote machine, not on your sleeping  windows machine? screen and tmux are programs to be run on the remote machine, and are nothing to do with how you connect to the remote machine.
Comment: @icarus Yes ! Sorry for the misunderstanding, I am brand new to run remote machines
Answer: Use screen or tmux on the remote computer. I prefer tmux for the improved scripting abilities.

Connect to the remote computer using whatever program you like that provides terminal emulation.
run tmux or screen. This will start a new shell in a "session"
In a tmux session if you want to send ctrl-b to a program then type it twice.
In a screen session if you want to send ctrl-a to a program then type it twice.
run your program in this new shell.
"detach" the tmux or screen session. For tmux type ctrl-b d, for screen type ctrl-a d
logout from the remote machine and put your local machine to sleep.
Power up you local machine and connect to your remote machine again.
attach to the session. For tmux run tmux -a, for screen run screen -r.
detach and reattach as often as you want. eventually stop your long running program and exit the shell. This will end the tmux/screen session.

Both tmux and screen can do a lot more, but this will get you started.


how to sample sine wave to 4 points dft output

Question: sinusoid  x(t)=1+sin(2*pi *500)
sampling rate :1000 samples/s
Can I have 4 points DFT output with the above data.
Answer: $ x(t)=1+sin(2*pi *500)$ is a sinusoidal signal with frequency 500 Hz and the sampling rate is 1000 Hz. So you have 1000 samples/sec and 500 cycles/sec.
So you have only 2 samples/cycle. So you can calculate 4 point DFT by taking only 4 values (consecutive) from the samples (Since it represent 2 cycles).
For distortionless DFT you should take atleast one full cycle. Here 2 point DFT also possible. As the number of samples increases the DFT graph become more smooth.


How do you evaluate if the Agile method is the right one for a specific project?

Question: I am looking for an evaluation method and criteria for determining if a project can be conducted using the Agile method (over traditional/waterfall). I would welcome examples ("definitely Agile", "definitely not").
Answer: To do Waterfall, you have to have a reasonable certainty of getting things right up front.
Because of this, you can only do projects which are very low risk, ie: ones where the vast majority of it has been done before. See "Waltzing with Bears", Tom de Marco and Timothy Lister, for why these projects may not be particularly useful, especially in software development.
Agile isn't just about keeping things responsive to change. It's also about keeping things responsive to learning, so in any situation where you've got a high amount of unknowns - people who've never used the technology before, or a new GUI that hasn't been tried, or an architecture that might not work with the legacy app - I would use Agile. Many of the traditional Agile practices, like stand-ups, showcases, retrospectives, etc. are there to get feedback, learn from that feedback, and share the learning, thus reducing the risk.
Even on a project where the requirements have been analyzed to death, the chances are that learning and discovery will be taking place. Agile practices which allow that learning to be shared can then be useful, even if the analysis practices are discarded.
The only danger of this is the transparency which it introduces, which often causes the people who asked for the requirements to ask for changes, in which case you should probably have gone with something a bit more Agile...
Some examples:

Configuring and installing a standard business package: Waterfall. Get the experts in to do it, don't do it yourself, or if you do, use Agile.
Greenfield project with no existing codebase: Agile.
Incremental move from legacy app: Agile.
Complete rewrite of legacy app: Agile.
Small changes to existing app: Agile*.
Fixed price, scope, budget: Waterfall might protect you a bit, maybe, but you'll still benefit from Agile learning practices.

*This is actually a good one to start Kanban with, which is related to Lean rather than Agile. Most stuff is suitable for Kanban if it's suitable for Agile methodologies anyway; they have more in common than different.
Comment: that's not really accurate about Waterfall. Most Waterfall projects have iterations in them and can include rolling wave planning.  Most of the highest risk projects in the world, like building spacecraft or bridges, are done using classical project management. In fact, project management as a discipline has really grown out of the need to manage risk in cases where a risk event is catastrophic (like the controls of an FA18 jet).
Comment: It's true, most Waterfall projects aren't truly Waterfall, in which case there's definitely room for Agile practices in them too. The only real difference is the focus on collaboration rather than hand-over, and shorter iterations. No bad thing for any project IMHO.
Comment: @Lunivore - Thanks for the answer and + 1 for the examples. I come mostly from an "iterative waterfall" background so this helps me understand better where agile fits.
Answer: My experience in project management so far has been only in software engineering and therefore I will try to answer from that perspective only.
The best place to use Agile is where you are expecting changes in the future. Since agile is lightweight and welcome changes, you may be in a better position to respond to changes (market demands, requirements change, feature updates etc) if you use agile.
As agile guru Martin Fowler suggest  http://martinfowler.com/articles/newMethodology.html#ShouldYouGoAgile moving to agile also requires a mindset change from all stakeholders and will be succesfull only if everybody is fully committed.
Also to continue to stay agile requires a lot of discipline (follow continuous re-factoring, TDD etc)
That leaves us with is Waterfall dead or is there still are some valid case for waterfall. My view is projects or disciplines where requirements are not expected to change, projects where a lot of initial analysis and design is required are still good candidates for waterfall.
Comment: I don't agree with the view that if you're not using agile then you should go waterfall. Iterative approaches are often better suited, because no matter how "stable" your requirements might be, it doesn't mean that you got them all right from the start. Most often you'll be better off with an iterative approach where you have shorter feedback loops and thus can adapt to what the customer really wants.
Comment: @asolanki - +1 for the note on stakeholders mindset + thanks for the resource link.
Answer: There are two areas which I would consider waterfall most appropriate.  This will be expensive to produce, and should have a fully functional change management process.

Highly regulated software where software must be to specifications, and all changes controlled.
Software where failure may be deadly (aircraft fly-by-wire software, nuclear reactor control systems, medical systems, etc.).  All changes will need to be approved.

A third case where waterfall might be appropriate would be a project with low risk, and known solution.  Most of these should be candidates for off-the shelf software.  These project might benefit from some use of agile processes.
At this point in my career, I would consider most other projects as candidates for Agile processes.  Things that I would classify as definitely Agile include:

Highly competitive environments.  (May need to release new version on short notice.
Projects with a high degree of uncertainty.  Agile techniques can be used to drive towards certainty.
Projects with lots of nice to haves.  Develop core functionality, and add nice to haves based on priority or discovered importance.  It makes it easier to delay non-core functionality until needed.

Look to the other methodology for things that will increase your certainty.  Agile can be used to clarify areas of uncertainty or risk for a waterfall methodology.  Waterfall can provide a stable platform underneath an Agile project.
One of the areas I have seen lacking in many projects is a good base to develop from.  I would expect a consulting organization to have defaults for these, but I haven't seen it in practice.  This includes things like:

Choice of tools where important: language(s), database(s), hardware platform(s), version control, change/bug tracking, etc.
Organizational/project standards and best practices.
Team organization, roles, and backup resources.
Answer: See the diagram on page 3 of this classic: Balancing Agility and Discipline by Barry Boehm - http://agile2003.agilealliance.org/files/P4Paper.pdf
You have 5 dimensions: Personnel, Criticality, Culture, Size, Dynamism. It's more like '5 dimensional' graph and the 'size' of the polygon should give you a visual que if Agile is more suitable or Process intensive. You can increase the number of dimensions are per your company's view point and add more dimensions...


How to reference a pilot study in an academic paper written in a foreign language?

Question: I presented a paper at a conference and later the conference published it in the (non-academic) conference journal. It was done in a foreign language. Afterwards, I used the same idea but a different data set, different references, expanded the methodology and wrote a separate paper (in English). I want to submit this paper to an academic journal but I am puzzled about how should I reference it while keeping the anonymity of the paper. If I cite it like any other paper, it would be clear who the author is as it would be the only non-English reference.
Comment: Are you sure the academic journal you would like to submit to has a double-blind review?
Comment: Are you the only author appearing in the non-academic jounral?
Comment: I did it together with my professor (I am PhD student), and yes, the academic journal uses a double-anonymized review system.
Answer: You can simply anonymize the source (omit it and replace with a comment along the lines of "this reference was omitted in the review version to maintain the integrity of the double blind review process") and once peer review is over but before publication, you put it back in.
Drop a note to the editor if you want to explain what you did with the reference, but this is quite common and won't surprise them. See the related questions about anonymizing papers for peer review, or have at look at these journal instructions.