Can Babel fees be extended to be a protocol level DEX?

Question: With Babel fees one can pay for transactions in native tokens. Could this be extended to where someone could pay for the ADA part of the transaction fee and also provide a swap with a different native asset the of the swap requestors choice? This would mean the ledger itself could act as a DEX with the lowest possible overhead.
Comment: I suggest you read the [guidelines for asking](https://cardano.stackexchange.com/help/asking) questions and consider re-writing the question to clarify what you are asking.
Comment: @gRebel I'm not sure how to word this better, any suggestions?
Answer: I think you may want to consider reversing the order here. The intent behind babel fees from my understanding is to leverage future conversion guarantees, DEXes, and other avenues for guaranteeing liquidity/conversion to ADA rather than to provide it's own mechanism.
We know these mechanisms will exist on chain from third parties so there is little reason for the foundational infrastructure itself to attempt to solve the problem as well. Instead it can leverage the existing solutions (once smart contracts are live) and allow competition and market forces to push for improvements and drive down prices.
It may be possible depending on how the negative values in EUTxO are implemented. The main issue is that as described in the blog post it currently relies on the assumption that transactions are only filled if the block producers can find a way to fill them. This would still likely be relying on conversion guarantees, DEXes, and other avenues for guaranteeing liquidity/conversion. Essentially this means if the block producers can't or won't exchange the tokens themselves, they'll have to use an on chain solution or the protocol will have to be extended so that non block producers can fill the requests. While this change can be done it would be very much non-trivial as it would likely require running an entire second network for negotiating order filling in between block production.
The issues with using this for running a DEX or liquidity system outside of just implementing it so that using it for DEXes would be feasible are that it'd create a lot of unnecessary transactions on-chain (which is inherent to on-chain DEXes) and depending how the system is implemented, it may put significant unnecessary load on the block producers. You'd probably want to run it on a state channel or side chain however both introduce new problems. The state channels would pose issues as joining may end up too expensive and side chains have significantly weaker security guarantees which would place using such a DEX somewhere in-between on chain and using a CEX in terms of security guarantees.
Additionally note that babel fees are in the paper phase at the moment. This means we won't see them on-chain for at least a year or two and the ecosystem may look vastly different than it does now so our assumptions as to how exchanges and liquidity systems operate may have changed significantly (based on the change we've seen in the last year or so).
TLDR: Maybe. We do not know remotely enough about how the system is implemented to know whether it would be feasible or even possible yet. When a paper on the topic is published, we should know enough to reason about the potential however as it stands it could be anywhere between completely feasible and impossible.

I may be off-base here. If so, I'd appreciate someone chiming in to correct me.
Comment: "guaranteeing liquidity/conversion to ADA" I'm wondering if it could be extended to letting there be liquidity/conversation to native tokens. That would always be more efficient than a dapp DEX because there would be no smart contract gas fee
Comment: This is under the assumption that Babel fees won't require smart contracts. They are essentially a method of deferring that conversion until later. The pool owners and delegators can elect to either take the tokens as rewards or exercise what effectively amounts to a future between the tokens and ADA. I suspect the exercising deadline will be on the epoch edge and which tokens will be exercised or not will be decided by either the stake pool operator or during delegation. In this supposed implementation this just means that those contracts are executing later not that they aren't executing.
Comment: The blog post states Babel fees do not use Smart Contracts, instead I believe you issue a UTXO with a negative value
Comment: I just reread the article and you are correct. I would caution however that since the concept has yet to reach the paper phase, it will likely change significantly and I suspect we will see far more restrictions on it than we see now. WRT what we know however I believe the answer to your question is maybe but most likely no. It should not be used that way on the main net as that will cause many unnecessary transactions that will lead to ledger bloat. On a state channel or side chain you could possibly use it however it would have a lot of limitations.
Comment: The short of it is we don't know enough yet and we won't have remotely close to enough information to accurately judge whether it will be feasible or even possible until a paper comes out. At the moment it is more a thought experiment than anything else and effectively anything is possible and nothing is possible until we see what changes it imposes on the ledger specification.


How are open-source projects able to sustain themselves?

Question: I always had this question in mind but couldn't find a proper place to ask. There are some really nice and great open source free software available on the net. How do these products sustain themselves financially? It is one thing writing a small utility which does something nice but writing a complicated product with whole lot of features is a totally different ball game. So to repeat myself again, how do they work financially?
Answer: There's lots of different answers.
Some projects are maintained by people who just want to do it for assorted reasons, including prestige or the knowledge that they're doing something good or because they thought somebody had to do it and nobody else was.  This section is almost certainly not as large as it was.
Some projects are maintained by people who want to be paid for support and the like.  Most Open Source companies are like that:  they want to create a popular product for free so that they can charge for related things.  It's a form of advertising.
Some projects are maintained by companies who aren't in that exact business.  Quite a few companies benefit from being able to use Linux, for example, or Apache, because they then have access to high-quality software that they don't have to write all themselves.
Suppose your company wants to sell web servers.  You want to have as much of the customers' money going to you as possible.  If you sell them Windows-based servers with IIS, a chunk of that money is going to Microsoft.  If you sell them Linux-based servers with Apache, you get to keep that money, and you have a lot more control over what you sell.  That may well be worth donating resources to assorted projects.  (Obviously, Microsoft has the opposite opinion.  They'd like the server people to produce cheap hardware that runs Windows and IIS.  Microsoft is likely the company most inherently opposed to Open Source, but even they take advantage of it in some ways.)
Let's look at Apple's use.  Apple makes their money selling hardware, but the main distinguishing feature is their ability to make user interfaces.  The iPhone does nothing previous smart phones didn't do, it's just a lot easier to use, and so it sold millions really fast and redefined the market.  They have a good idea as to what they're selling.  Nobody's going to buy Apple for operating internals, so by having the Darwin part of the OS as Open Source they can get some outside help on it.  They also started with Open Source after failing to produce a top-quality operating system themselves.  Nobody's going to buy Apple for the printer software, so it was easier and faster to use CUPS.  They will for the interface, so that's closed down tight.
Comment: The third reason, financial sponsorship from big-name companies with symbiotic relationships, is probably the biggest chunk if we look at the the "open source industry"'s pie size financially. Just my guess.
Answer: Here's one potential way: support.  Support can be a money-maker.
Linux distros are "free", but there are training costs to companies as most employees won't be familiar with the technologies.  So consultancy becomes a viable source of income for open-source projects.
A real-world example: the company I work for wanted to introduce automated acceptance testing (using tools like selenium, fitnesse, fitsharp etc.)  The tools are all free, but to implement them in an effective way is not that straightforward. So a consultant (somebody who actually developed these tools) was brought in to suggest the best ways to implement them.
I'm sure other answers will give other ways that open source projects can sustain themselves, this is just one way...
Answer: Even though this is an old question, I don't see the most obvious answer to me - dual-licensing. Many successful open-source projects offer more than one version of their product - the core being released under open-source and premium editions offered under commercial licenses (this model is often called freemium pricing).
Good examples of such projects include MySQL and Magento. I wrote extensively on the subject of making money from open-source on my company blog, might be of interest.
Answer: If a project is popular then donations can help offset some of the costs or even make money. Its most likely not going to be much unless the audience is huge, but its enough to pay for webhosting or a few bills.
In the long run its for pay support or consultancy. Ubuntu is completely open source, but Canonical provides enterprise level support and consultancy for it and makes decent money from it. The issue with this though is that your project has to be large enough for enough people to want to migrate or setup software to yours.
Getting to the point of making money can take years of building a consumer base and lots of hard work.
Comment: Does **decent** mean Canonical is profitable?
Answer: If you develop OSS with a strong copyleft licence (GPL or AGPL), you can then charge for exceptions to that licence, allowing people to include your code in their proprietary products. If you use a more permissive license (X11, Apache, MPL), they can include your code in their product anyway, so you have nothing to sell them.
Comment: How workable is this in real life?  Any examples?
Comment: @Alison, MySQL has been developed that way, under the GPL. http://www.fsf.org/blogs/rms/selling-exceptions
Comment: any idea if they actually make money?  Also I'd suggest MySQL is fairly exceptional - it's unlikely that their level of usage will be achieved by the average project.
Comment: I don't know of any, but it is theoretically possible.
Comment: @Alison,
x264 is another example: http://x264dev.multimedia.cx/archives/584
Comment: @Alison, http://programmers.stackexchange.com/questions/30856/licencing-foss-for-profit
Answer: Apple pays for maintaining CUPS, WebKit and many other open source projects.
They use these technologies in products and services they sell.
Answer: This is the key: http://www.codinghorror.com/blog/2010/06/the-vast-and-endless-sea.html
The thing that business people do not understand. You have a bunch of good developers, who really get all of the intrinsic motivators you could get. You don't have to pay the whole infrastructure a commercial product comes with (an enterprise with a lot of people not needed to create the product, such as administration, lawyers, marketing, advertisement, etc.). Some projects actually generate enough income (through donations, commercial support/licences), but that's rather rare. And then there are a few projects which are basically open sourced because it makes them much cheaper to maintain, or because they couldn't be sold.
Answer: Spare time? Some people are simply able to manage their time so that they have spare time outside of their job hours. You don't have to make money off of every single thing you do. If you worked for a living fixing roofs, you wouldn't expect someone to pay you to patch your own roof if it was leaking, would you?
Furthermore, a lot of large open source projects turn into companies that find creative was to make money. Selling support, merchandise, extra unnecessary features. There are lots of ways to make money off of open source.
Also, some Open Source projects gather very large teams of people with very different circumstances. People that can be active in the project at different times, making the project very active.


Is sticky pepperoni a sign of spoilage?

Question: My child ate some pepperoni that was sticky, but didn't smell or taste bad, and was before the expiration date. Is that a sign that it might've spoiled early, or was it likely still safe?
Comment: It seems like pepperoni is always a bit sticky; it certainly sticks to itself in the package anyway. I take it you mean more sticky than that?
Comment: A little bit. They were all stuck together a bit stickier than usual.
Comment: Did you just open the package? If not, was the pepperoni refrigerated and in a sealed bag to keep air away?
Comment: It was refrigerated but not sealed for 2 weeks. Air could get to it. It came in a non resealable bag.
Answer: Pepperoni has quite a bit of fat in it, and it's going to break down over time as it ages in the fridge (just like the meat that went into it). That can result in a sort of tacky feeling to it. You get this in things like beef summer sausage, too. It's always rather dry by the time it spoils, which takes quite a while.
Sticking an uncovered sausage in the back of the ref for a day or so is something many folks do to bring out the spices it contains a bit more prior to cooking. It also tends to come out a little tacky, depending on fat and preservative content. I do this with store-bought Italian sausage to get the fennel and anise a bit more pronounced.
If it doesn't smell acrid or rancid, and feels like pepperoni despite being a little tacky, it's probably fine. When preserved meats go bad a few parts of it start to have an acrid sort of odor, quickly followed by the rest. It's harder to spot initially in chorizo and similar, but bad pepperoni really gives itself away pretty quickly.
Also, taste a small piece. If it's rather sour, you probably don't want to use it.
Source: Me always being given the job of cleaning out and rotating stuff in the walk-in in at a place I used to work that made a lot of pizza.
Answer: The stickiness was, regrettably, probably sodium nitrite or a similar preservative. When applied in amounts that don't result in liquid "run-off," it tends to be sticky. I always rinse it off with cold water for aesthetic purposes, but no real precautions are needed.

Is sticky pepperoni a sign of spoilage?


Do I really need 10 AWG wire for a AC condenser that says 15 AMP max?

Question: I'm buying a used AC condenser for a rental property. The unit says max amps = 15 (see below), however the HVAC guy tells me I want a 20AMP double pole breaker with 10 AWG? I would have though 15 AMP double pole with 12 AWG would be fine. Is he correct? The wire length is probably 20 feet max.
Comment: It says right on the label that the fuse or circuit breaker cannot be above 15A, so based on his statement that a 20A breaker is necessary... I would get another HVAC guy.
Comment: Bottom line is, there is NO blanket "80% rule". Many people who don't know what they are talking about simply apply it to everything as a one-size-fits-all rule, which is WRONG.
Comment: I suspect your HVAC guy is applying the "80% rule" assuming that the condenser requires 15A (by misreading the label). In fact the label already has the "80% rule" applied to its actual 12A requirement (80% of 15 is 12).
Comment: I might be doing something wrong, but I'm only calculating 12.2 amperes for branch-circuit conductor ampacity.  (9.2 amps + 0.7 amps + (9.2 amps * 0.25) = 12.2) (NEC 440.33).
Comment: Thanks for confirming my suspicion. He mentioned something about an 80% rule? Can someone explain that.
Comment: The guy who told you all this has NO clue WTH he is talking about!! Get a new HVAC guy, or better yet, find an electrician who knows.
Answer: It says specifically that you must use a 15A breaker max.  Max means not 20.
It also says you must use a HACR breaker.   All new breakers are HACR.
You are required to comply with a component's labeling and instructions. NEC 110.3.   You cannot go "la la la, I think I'll do something else because reasons".  Unless you can convince your AHJ of the reasons.  (AHJ is your local government which issues permits and does inspections.)
Why is the wire 10 AWG? Being Future-proof.  The cost of wire ($5) is next to nothing compared to the cost of tearing out 12 AWG wire to replace it with 10 AWG (hundred$). The last guy installed the heavier wire so you'd be "good to go".   You do still need to change the breaker to correct size, but that's cheap.
Comment: The HVAC guy obviously knows more than the manufacturer and engineer(s) who approved that label, apparently. But seriously, folks, max means max. Chances are that a bigger breaker could allow an objectionable amount of current into the condenser, resulting in something bad happening, and leaving you liable if you're the one who flaunted the label and put too big of a breaker on the circuit. You don't know what might happen. Presumably the engineer who put the specifications on that label does know, and said the breaker cannot be bigger than 15A.
Answer: Here is a good article and presentation about 100% vs. 80% rated breakers.
http://blog.schneider-electric.com/datacenter/power-and-cooling/2014/06/12/clearing-confusion-80-vs-100-rated-circuit-breakers/
In this case, I trust your HVAC guy even though it appears to me as well that he is oversizing the wire and the breaker.
I am an engineer who has worked on testing breaker and relay products for electricians in the past. Thermal-magnetic breakers can trip at levels below even their 80% rating if temperature in the breaker panel is high. Also, a brown out or saggy mains voltage can cause increased current needs to your device and result in breaker trips. Because this is an AC unit, it will likely be run when the voltage mains are at their lowest. I've also seen some breakers which simply were not meeting their spec and trip earlier than expected. As for the 10AWG wire, I suspect he chose this not to meet code, but to eliminate voltage drop in your wire run and hopefully stop any nuisance tripping.
So your guy might be just playing it safe, but I think he may have reasons to suspect you will be getting nuisance tripping on that unit unless you do as he said. You wouldn't want your tenants to be calling over and over because you cheaped out on this. And you would likely then call to complain to him that he messed up. :)
Comment: @RetiredMasterElectrician, you need to associate with a better class of electrician then. I have never in my life simply followed that silly list of breaker/circuits for those items, except for the dryer and water heater.
Comment: It's probably because the people who wire houses don't take time to do a complete NEC calculation on most houses. They will always wire the following 30A for the AC, 30A for a dryer, 30A for a water heater, 50A for a range and 70A for the electric heat. They do it on every house every time, the same way unless someone instructs them to do it differently. Then they may still do it 50 percent of the time.
Comment: @RetiredMasterElectrician, I agree! You are more qualified to answer than me so if you answered I'd upvote you. As I learn little by little what electricians do at different sites, it seems that just because something is up to code doesn't mean it's right. But also, I've been humbled by the knowledge of other electricians as well.
Answer: Typically in an ideal situation I would use the next size up breaker and size the wire accordingly. Then at the disconnect use the size fuse required by the unit. The fuses are slow blow so they won't pop with the high startup current but the breakers blow quickly. Doing it this way tends to have fewer nuisance trips. Wiring everything for 15 amps would be perfectly acceptable and realistically should not have any problems. The important thing is to have something that will trip at 15 amps to avoid damage to the air conditioner.


The syntax highligher for this js script seems to have a bug for the code after the */

Question: Regarding this question, seems all stuff after the /* was grey-ed, with or without finding the matching */.
Answer: This is a weird case. The syntax highlighter determines what language is in use by checking the tags on the question, but bash is set to use the bsh syntax highlighting and shell-script uses the sh highlighting. When there's a conflict it falls back on just detecting the language based on the code, and it's wrongly detecting it as C (we don't control this, it's part of google-code-prettify)
I'm not sure what the difference is between the bsh and sh syntax highlighting, so I don't want to change the tag assignments, but I fixed the question and answer to use sh highlighting


XsltListViewWebPart stuck on loading

Question: We are currently running SharePoint 2010 Server SP1 + June CU. Our site collections were migrated using database attach method from SP2007. When we configure 2 or more  XsltListViewWebPart that point to any list or library and they use collapsed grouping in views the hanging with loading... message when you click the expand icon. If we one have one XsltListViewWebPart and a group by set to collapse it works fine. Our farm consists of 3 WFE load balanced behind a Cisco ACE. Has anyone else ever run into this problem before?
Answer: Modify this web part -> Locate the "Enable Asynchronous Update" checkbox under Category "AJAX Options" -> Check it -> Verify
HTH,
Vishwajit
Comment: Vishwajit's solution worked perfectly for me. (Thank you! Vishwajit) It appears I lack the rep to upvote the solution but I wanted to be sure everyone know.

XsltListViewWebPart stuck on loading


Historical Data For Options?

Question: Is there a site  where I can get historical options data?  Where I can see what the price of a particular option was several days ago?
Answer: Web sites that offer free historical data are few and fleeting.  The amount of data is usually limited unless you $ubscribe.  They tend to disappear fairly quickly which I assume is because they can't get enough revenue from ads to survive (costs are high because of the amount of data is massive).
You can $ubscribe to data vendors for data.  They tend to be expensive.
You could go into your broker's Time and Sales for the data but that's a massive undertaking since there can be thousands, even tens of thousands of quotes per option per day to scrape.
If you broker provides price graphs, the easiest way would be to enter a quote, bring up the graph, select a time frame and cursor to over to the earlier date and read the price.  Even this is shaky because options may trade by appointment and the option graph will only plot actual trades, not the price of it which varied intraday as the underlying went up and down.
Comment: US OPRA stock options on the nanex feed are 20 gigabyte PER DAY and more. That is highly compressed binary ;)

Historical Data For Options?


Split-screen in Left 4 Dead 2

Question: Is it possible to play the PC version of Left 4 Dead 2 in split-screen, where one player uses the mouse/keyboard and the other uses a gamepad?
Answer: Yes, you can. You have to make sure you know your way around the console, and playing online might or might not work.
Basically, you have to enter these commands in the console to make it work:
<code>ss_enable 1
ss_map "map_name"
connect_splitscreen localhost
</code>
You have to make sure your Xbox 360 controller is set up correctly, for that, read this forum post: Left 4 Dead: SplitScreen PC Guide.
It's possible play split screen with a non-Xbox 360 controller, but you'll need to set up your own controller configurations by editing edit \left4dead\cfg\360controller.cfg. The lines you'll need to edit are the ones starting with "cmd2 bind".
Answer: EASY STEPS FOR L4D2 SPLITSCREEN  By ChilledGame
How to play L4D2 Splitscreen || Keyboard/Mouse and Controller
How to play L4D2 Splitscreen || Two Controllers
YouTube videos:
Keyboard/Mouse + Controller

Two Controllers (PS4 or Xbox doesn't matter)

How to play L4D2 Splitscreen || Keyboard/Mouse and Controller
STEPS

Enter 'Big Picture' mode
Click on the gear icon
Click on the option 'Controller Settings'
Ensure that your controller is configured and supported here, To this just click on what type of controller your using.
Now launch the game.
Once in the main menu, open up the game console by pressing 'Tilde' key. Once the game console is up, type the following; ss_map c1m1_hotel. This will load up the Hotel level. You can find the code to all the other maps and levels here.
When in game open up the console then type in connect_splitscreen localhost 2.
Open up the console again and type in sv_cheats 1.
Once again open up the console and type in_forceuser 1.
Finally you may need to edit the key/buttons for your keyboard and mouse.

===================================================
How to play L4D2 Splitscreen || Controllers
STEPS

Enter 'Big Picture' mode, by clicking on the steam icon. A drop-down should appear, from there click onto 'Big Picture' mode.
Connect your controller and ensure that it is configured and supported on settings. After that you launch your game.
Next go onto 'options' and then 'keyboard/mouse', from there ensure that the developer console option is changed to 'enabled'. This will allow you gain access to the game console.
After this go back to the menu and hit the 'Tilde' key. This will allow us to access the game console. Once in the console, enter the following; ss_map c1m1_hotel.
Once the game has loaded, open up the console once more and type the following; connect_splitscreen localhost 2.

======================================
Hope it helps out :)

Split-screen in Left 4 Dead 2


MOSFET DRIVER- HIGH side vs LOW side

Question: I am trying to understand mosfet drivers in general, no specific part. And I am encountering low side and high side drivers. My question is that if for example: I have a N channel mosfet as a high side switch and another identical N channel mosfet as a low side switch. Why do I need a different driver for each? Ultimately you want to charge gate capacitance quicklyand since they are both N channel what is the difference of how I need to charge it if its high side or low side?
Comment: Vgs must be a few volts above source in either case; when switching 12v low, let's say 5v (0+5), but when switching high it's 17v (12+5), and a lot of times the switched voltage is the max voltage used by the circuit, so the high side needs special handling to get to 17v when the max of all else is 12v.
Answer: A low side FET driver's circuitry is referenced to ground.  Therefore it's easy to interface to controllers or even logic signals.
A high side N-FET has its source flying up and down between ground and the drain voltage, maybe higher with parasitic ringing.  So does the source reference connection on the driver.
So a high side driver generally has level shifting circuitry that allows you to control Vgs even though the source is at high voltage.  It may also have features to help with bootstrapping the high voltage, or desat protection, etc.
For N-channel switch applications the high side driver may have a charge pump built in to allow it to drive the gate above the source.

MOSFET DRIVER- HIGH side vs LOW side


error message from apple diagnostics after fan replacement

Question: This is a late 2012 mac mini. I recently replaced the fan, which was making a lot of noise. The replacement is not from apple. Everything works fine, and the system is quiet. But I ran an Apple diagnostics which gives me the following error: 4MOT/1/40000002-Exhaust-0. Is this because the fan has not been installed properly or it is Daignostics not liking a non-Apple product? Many thanks for your advice
Answer: The "MOT" in the error code indicates, as you may have guessed, trouble with a motor of some kind.
It would be logical to assume it points to the fan you replaced.
I wouldn't expect it to be caught during a hardware test, although these fans are controlled by a chip that precisely modulates power, and could detect when the motor isn't acting as expected according to the input, which I guess could be described as "diagnostics not liking a non-Apple product."
Regardless, it does mean at the very least that the replacement part you used isn't identical to the factory part. Is the fan spinning at all? You say the system is fine, but also quiet. Could this be because it was installed incorrectly and isn't even functioning? I can't imagine how you could install the fan incorrectly, but if you don't hear it spinning at all, maybe you should take another look to see if everything is connected, and you didn't destroy the fan connector, which is too easy to do.
Where did you buy the part, and was it listed as compatible with the model you have? Even if it is a third-party part, I find it hard to believe that AHT would detect it as malfunctioning if it had the right specs and was actually connected to the board.
Comment: Tx for taking time to provide a  response. Your para 2 is helpful. Yes, the fan is spinning and I don't have the sudden noisy whirring, which made me concerned. I bought the part at Amazon. Tx again.


Smart thermostat for single-zone HVAC

Question: I bought my first home (townhouse) I want to install a smart thermostat
I have only one HVAC and the thermostat is located in the main floor.
I have noticed that upstairs is hotter than the main floor, ecobee 4 has sensors you can buy for each room.
If I only have one furnace is this an overkill since the HVAC will blow air to the whole house?
Comment: VTC as opinion-based. However, just because you only have one HVAC unit does not mean it heats / cools all rooms the same. The main benefit (IMO) of the ecobee in particular is the ability to set the temperature based on the room(s) where you are, and the sensors allow you to do that. With your upstairs being hotter, the sensors would allow you to run the AC more at night, for instance, so that your upstairs is more comfortable (though your downstairs might become a bit too cold), or run the heat more so the downstairs is more comfortable.
Answer: Zone system
A true zone system allows different areas of the house to be isolated, by closing off certain areas using dampers, or just having completely isolated air handlers.
This allows fairly accurate control of the temperature each zone, allowing a specific (and if desired, different) temperature to be maintained in each.
Multiple sensors
The Ecobee is more of a "multiple thermostat" or "zoned sensors" system (not sure if there's a more proper name). The limitation is there is no isolation in air handling, so multiple zones cannot be controlled independently.
However, there are two distinct advantages over the typical "single thermostat" setup:
1) The house can be maintained at a temperature based on averages of all sensors
As an example, let's say right now the upstairs is 26 while the main floor is 21, and your target is 21.
By averaging everything, it'll keep the house slightly cooler and set the upstairs to 23 (a bit above target) while the downstairs is 19 (at bit below target).
2) Which sensors you're using can be scheduled
This means during the day, you can give priority to the main floor living spaces, while at night you give priority to the upstairs.
The downside is during the day the upstairs floor is uncomfortably hot, and during the night the main floor is colder than desired, but the areas where people mainly are stays at a nice temperature.

Aside, I have an Ecobee3 and this works extremely well for me. I also use the "ensure fan runs for at least x min/hour" feature which recirculates air and (I think) keeps everything more even.

Smart thermostat for single-zone HVAC


Is it obligatory to pray at the mosque for a baaligh?

Question: I wanted to ask whether it is obligatory to pray at the mosque for someone who has reached the age of puberty, and if his parents disagree with him even thoufh he lives close, then in this matter what does he have to do?
Comment: No it isn't see [here](https://islam.stackexchange.com/q/32602/13438) and [here](https://islam.stackexchange.com/q/24798/13438).
Answer: Sahih al-Bukhari » Book of Call to Prayers (Adhaan) >>Narrated Abu Huraira (RTA):

Allah's Messenger (ﷺ) said, "By Him in Whose Hand my soul is I was
  about to order for collecting firewood (fuel) and then order Someone
  to pronounce the Adhan for the prayer and then order someone to lead
  the prayer then I would go from behind and burn the houses of men who
  did not present themselves for the (compulsory congregational) prayer.
  By Him, in Whose Hands my soul is, if anyone of them had known that he
  would get a bone covered with good meat or two (small) pieces of meat
  present in between two ribs, he would have turned up for the `Isha'
  prayer.'

We all know how soft our prophet (SAW) was, and he want to burn the houses of those who don't come for obligatory prayer to mosque.
I cannot say anything about your next question " if his parents disagree with him....."
Show this hadith and pray for them, may Allah guide all of us.
Comment: Brother, thank you for your answer but that doesn't really answer the question, besides, hadiths like this need context and other hadiths to support it that are like this hadith because when you really research this particular hadith you find out, the people who he ﷺ meant, were people who lived near the mosque at a distance where they could hear the Adhan naturally, so this doesn't really answer it... i want a conditionless answer and etc. And you had good explaining, but i didn't get the answer i wanted sorry brother✌...
Comment: Your question don't have any condition like distance or weather situation or hearing Adhan, I am living in USA, and it is not allowed to use the loudspeaker for adhan, I never heard adhan until I go to mosque. At the time of Prophet SAW city was small, call the adhan and everyone can hear that.
Comment: I understand what you mean but the conditions of it being obliged have to meet my condition for it to become obliged, and you didn't explain the conditions, sorry...✌


Bare Soil Detection

Question: I try to find bare soil areas. Those which are bare over the whole year and those which are fresh harvest and remain bare over a certain time. I try to do this with sentinel-2 data. But the Problem is that the cloud cover does not allow a sufficient detection. What kind of Satellite Products and/or Indices can help me out with this problem. Can anyone give me a hint in which direction I have to look?
Answer: I would recommend investigating Synthetic Aperture Radar (SAR) data and soil indices such as Normalized Radar Backscatter soil Moisture Index (NBMI). Radar has the benefit of being able to penetrate clouds, unlike spectral sensors.
The following are some resources to get you started.
Shoshany, M., Svoray, T., Curran, P. J., Foody, G. M., & Perevolotsky, A. (2000). The relationship between ERS-2 SAR backscatter and soil moisture: generalization from a humid to semi-arid transect. International Journal of Remote Sensing, 21(11), 2337-2343.
Moran, M. S., Peters-Lidard, C. D., Watts, J. M., & McElroy, S. (2004). Estimating soil moisture at the watershed scale with satellite-based radar and land surface models. Canadian journal of remote sensing, 30(5), 805-826.
Barrett, B., Whelan, P., & Dwyer, E. (2013). Detecting changes in surface soil moisture content using differential SAR interferometry. International journal of remote sensing, 34(20), 7091-7112.
Answer: You may want to try spectral unmixing.  Here's an example to get you started link to script:
<code>// Function to mask clouds using the Sentinel-2 QA band.
function maskS2clouds(image) {
  var qa = image.select('QA60')

  // Bits 10 and 11 are clouds and cirrus, respectively.
  var cloudBitMask = 1 << 10;
  var cirrusBitMask = 1 << 11;

  // Both flags should be set to zero, indicating clear conditions.
  var mask = qa.bitwiseAnd(cloudBitMask).eq(0).and(
             qa.bitwiseAnd(cirrusBitMask).eq(0))

  // Return the masked and scaled data, without the QA bands.
  return image.updateMask(mask).divide(10000)
      .select("B.*")
      .copyProperties(image, ["system:time_start"])
}

// Map the function over one year of data and take the median.
// Load Sentinel-2 TOA reflectance data.
var collection = ee.ImageCollection('COPERNICUS/S2')
    .filterDate('2016-01-01', '2016-12-31')
    // Pre-filter to get less cloudy granules.
    .filter(ee.Filter.lt('CLOUDY_PIXEL_PERCENTAGE', 20))
    .map(maskS2clouds)

// First, let's find a cloud free scene in our area of interest.
var image = collection.median()

// Use the reflective bands.
var bands = ['B1', 'B2', 'B3', 'B4', 'B5', 'B6', 'B7', 'B8', 'B9'];

// Now, delineate polygons of 'pure' regions.  Click +New Layer for
// each polygon.  Name the imports 'bare', 'vegetation' and 'water'.
// Get the mean spectrum in each of the endmember polygons.
var bareMean = image.reduceRegion(ee.Reducer.mean(), bare, 30).values(bands);
var waterMean = image.reduceRegion(ee.Reducer.mean(), water, 30).values(bands);
var vegMean = image.reduceRegion(ee.Reducer.mean(), vegetation, 30).values(bands);

// Constrained:
var constrained = image.select(bands).unmix([bareMean, vegMean, waterMean], true, true);
</code>
Comment: That's an interesting thing ;) Thanks for that! Two questions: 1) How much is a good amount of sample data? Is it better to have only one polygon like in the example above or is it better to have much training data as possible? 2) in the example above all bands will be used, but what is when a few of the bands have not a clearly different spectra. Is it better to exclude this bands?
Answer: Sentinel-2 is best for this, stick at it. You need to use multiple scenes and periods to get around the cloud cover. Landsat, Spot, Aster still all have clouds. Basically, clouds exist so you must overcome them.

Bare Soil Detection


How to build deck posts into clay soil

Question: I am a novice diyer and I am attempting building a ground level deck in my back garden. I have seen so many different ways to dig and fill the hole it's left me more confused than when I started.
What is a great way to ensure longevity with regards the posts going into the ground? Many thanks
Answer: Post longevity:
Concrete, below frostline (varies with where you are), with a footing, reinforced with steel rebar kept 2" from the face of the concrete. Use brackets or pads to keep wood from touching concrete aboveground.
Hole: Cheap, or Lazy?
Cheap - post hole digger (clamshell type) or mattock and shovel (depends how hard the clay is when you try to dig the hole - will vary somewhat with water content through the year.)
Lazy - equipment - excavator/backhoe, power auger, etc. - note - power auger needs to be on a tractor or similar to really be lazy - the ones you hand-hold seem to be quite a workout to use. And always be sure you know what is below before digging - call digsafe for official marking before you start, and attempt to determine what private services you may have in the area such as plumbing lines, sprinklers, exterior lighting wires, etc.
Cheap and Lazy - You said a "ground level deck" so patio blocks right on the ground, no holes at all. If not quite that lazy a sand bed will help future performance of the surface some, but it may need to be taken up and regraded from time to time anyway.

How to build deck posts into clay soil


Difference between convex hull algorithms

Question: I was wondering what are the main differences in terms of efficiency of convex hull algorithms?
Brute force algorithm is inefficient due to iterating over every three vertices in our set and its time complexity is $O(n^3)$ and probably is never good to use.
But what about Gift wrapping, Graham's scan and Chan's algorithm? My understanding is that Graham scan and Chan's are efficient, Graham scan on smallers sets and Chan's algorithm on bigger sets but what are main pros and cons of those three algorithms? When to use which ?
Comment: I would say the main differences of these algorithms come from understanding the question from different perspectives. They all work in $O(n\log(n))$, and hence the reason you learn them all in a computational geometry course is that they give different perspectives to problems, which can be useful for constructing other algorithms for other problems later on.
Comment: @nirshahar not correct: gift-wrapping can be require order of $n^2$ time in the worst-case (when a constant fraction of points lie on the hull).
Answer: If $n$ is the number of 2D points, let $h \le n$ be the number of points on the convex hull. Then:

Gift wrapping takes time $\Theta(n h)$, which can be $\Theta(n^2)$ in the worst case. It is relatively simple to implement. Gift-wrapping generalizes to 3 dimensions and beyond.
Graham scan takes time $O(n \log n)$. It is very easy to implement especially if you use the so-called monotone chain (also known as Andrew scan) variant. It does not generalize easily to 3 dimensions and beyond.
Chan's algorithm takes time $O(n \log h)$, which is asymptotically optimal. It is somewhat more sophisticated to implement than the Graham scan. It generalizes to 3 dimensions.

Therefore, my suggestion would be:

If your points are 2D, go for the Andrew scan. The difference between $\log h$ and $\log n$ may not be worth the extra complications of Chan's algorithm unless your dataset is truly huge.

If your points are 3D, Chan's algorithm makes sense and is faster than gift-wrapping in the worst-case.

If your points are in higher dimension than 3D, use gift-wrapping, since the other algorithms either don't work or require very complex adaptations anyway.


How long are people genin before they take the chunin exam?

Question: Team 7 (Naruto's team) existed for at least while before they took the chunin exam, and they took on a number of missions before taking the chunin exams. I can't remember, however, how long they exactly existed as a team before the exam. How long were they genin before the exam? Is that the normal length? Is there some sort of mission requirement where they have to complete a number of missions before they can take the exam?
Answer: The exams happen twice a year. The genins that participate are chosen by their group leaders. So if the group leader is of the opinion, that they are ready at age 6, he sends the genin to the exams, if he's of the opinion that they are not ready yet, he lets them wait. There is no special requirement to take the exams (at least nothing was mentioned), it's just the group leader who decides. This can be seen in chapter 35, when Kakashi, Kurenai and Asuma suggest their team for the exams. Although Iruka protests, he can't do anything against it. That does not mean, that the genin can't decide against it, though. A ninja can't be forced by his group leader to do the exam.
Answer: There is no definitve answer to this as no set age or timeframe is given in the manga, anime or on the wiki. Keep in mind ninjas like Itachi who became a chunin at age 10 and kakashi at age 6. (special cases yes but they did become chunin).
So if I were to give an answer, it would be until when they decide to take the exams.
As per the wiki

To become a chūnin, a genin participates in a large examination, known
  as the "Chūnin Exams".

Again, also as related, keep in mind that not all academy students become Chūnin, so that might apply here too.* No doubt they would have to try again.
And then again there is also this guy.. Kosuke Maruboshi who even though by choice, has been a genin for over 50 years. This could also apply to your question.*


What should I use to fill cracks in my wood door?

Question: I'm almost finished stripping multiple layers of paint and varnish off my front door.  It's revealed some really nice detailing that was previously hidden by paint.  I'd like to stain and seal the door now, but each of the 4 panels on the lower part of the door have substantial cracks in them.  Right now, those cracks are filled with paint.  What can I use to fill the cracks? Sorry for the blurry picture of the door]2
Answer: Word of advice, do not sand the door anymore than what has occured already. You can see how there are a few lighter areas where some dings are that the "patina" has been removed by something. Sanding will ruin the patina, making the door look blotchy as well.
On old furniture and doors where the cracks are not structural, burn in sticks are what I use. They are made of lacquer, and if you finish your door in a water based or poly finish, this will fill the cracks nicely. Burn in sticks can be bought on Ebay, its where I got mine, they come in a wide variety of colors, and the color you see is the color you get, they don't change color once applied.
Once the door is sealed, NOT finish coated you get yourself handy a heat gun. Use that to melt the stick of the color you want where it starts to flow down the stick, careful. Then move it onto the door with out dripping and push it into the crack. On small cracks, I use a putty knife heated and set the stick on it to melt it a little and use the knife to apply it. When the crack or hole is sufficiently filled, I take the heated putty knike and flatten it out, removing the excess. This will leave a small skim over the surface, which will then clean up with a little lacquer thinner on a clean rag. Do not get the rag to wet, it may try to dissolve the sealer too.
Apply the finish coats over the repairs as you normally would.
Use this only in cracks, not joints, wood needs to move and if it is placed in a joint you will hinder the movement, doing more harm than good.
Comment: Thank you, Jack!  I've never heard of Burn in sticks.  I found them on Ebay as you suggested.  This may be what I try.
Answer: Nice door - good work on the restoration! First I'd try to remove as much of the paint as possible. A putty knife and razor blade will probably help. Then the best filler would be a medium-brown tinted epoxy that matches the color of the stain you'll be applying. If that's not available, a stainable wood filler should be used.
Comment: Thanks for the compliment, Aaron!  I'm having fun doing this work and I was especially excited to find some beautiful detailing around the window when I removed the layers of paint.  I'd post a picture here, but I don't see any way to do it in the comment section.  (I have found toothpicks and a dental pick quite helpful with the detailing).
Comment: You're welcome. This kind of work can be really difficult. One thing... I don't know what colors you're trying to match this with but is encourage you to minimize your use of stain if possible. A lot of times people assume wood needs to be stained, and I'm reality it just needs to be finished. In my opinion, the natural colors and variations of the wood are usually suppressed by stain and not at all helped. In this case depending on how thoroughly you sand it, you might get uneven shades on the surface. As long as the clear finish job is done well, even that can look tasteful.
Answer: The cracks look pretty straight, so I would try to cut a thin sliver of wood, glue and wedge it in. A table saw is the easiest approach to this task. You are cutting a very thin piece that may tend to fly off the table, so be sure to wear safety glasses and stand slightly to the side, away from the strip about to be freed.
The wood looks like oak. If there is some old oak around the house, that would be my first choice. If not, I would buy some new, cut some strips, stain them to about the color of the door before trying to insert them.
To put them in, I would work from both sides, using strips that are less than 1/2 the thickness of the door. After putting in the strip from one side, you could use a bit of exterior grade wood filler in the middle before inserting the strip for the other side, but probably not necessary.
I would try not to get glue on the face of the repair (wipe it off while still wet if you do), because it might interfere with any stain you apply ti the door after repair.
Comment: Oh Bib, you give me much too much credit!  If I were a wonderful craftsperson, I would certainly do this, but I'm just a simple DIY'er trying to clean up a 100+ year old home.  I think I'll leave this solution for the more experienced folks.  Not having a table saw makes this more complicated also.  Thanks for the suggestion, though!


Reduce pedal noise when recording

Question: When recording my upright piano with a zoom recorder and a dynamic microphone, I find that the noise from the sustain pedal is quite noticeable. I usually don't think of it while playing. Is there a trick for reducing the amount of noise from the pedal?
Answer: Depending on whether it's creaks or thumps from the pedal itself or from the damper mechanism, you could try alternative mic positions.
From the front, aim higher up the body, or mic it from the rear, or even lift the lid & mic it inside.
One of those might just be enough to reduce it - otherwise you're going to have to learn to release less abruptly, or get the mechanism serviced.
Comment: @FredrikArnerup For a detailed description of how to adjust pedal technique, see [How do you learn pedals?](https://music.stackexchange.com/a/101869/70803)
Comment: I just checked out a recording I did of an upright in a medium-sized dead room, quite some years ago. Pair of AKG 414s quite tight & wide to the back of the piano,  which was a couple or three feet from the wall. Entire band live out in the same room. Quiet ballad, so no stomping;) Lovely mellow sound, not a clunk to be heard in the whole recording.
Comment: Recording from the rear is not practical for me. I guess I'll have to learn not to release the pedal all the way.
Answer: Aside from other pretty much reasonable recomendations to relocate or reorient the microphone, there is one thing you can try for a bumpy pedal:
Insert something soft (rubber, few layers of fabric, etc...) in the opening over the pedal. You may need to band it to the pedal in order to keep it from falling off.
Comment: If it is too thick (like 1/3-1/2 of the pedal travel) it will interfere with the sustain mechanism release. Other than that, the piano is expected to contain such damping. It simply wears out with time and use and becomes tinner and stiffer. The proper solution, of course, is to get the piano fixed by a professional, but this proper solution is neither cheap nor quick.
Comment: Is there a risk that it naturally keeps the pedal slightly pressed down if it's "too thick"?
Answer: The unavoidable truth is that pianos, particularly older upright pianos, often ARE mechanically noisy.  Attempts to record one 'in the room' may be doomed to failure.   If you can pull the piano away from the wall try micing the soundboard from behind. Or point the mic down into the opened top of the instrument (and discover the hammer mechanism is noisy too!).
Also, of course, consult your piano technician.  And don't 'stomp' on the pedal while playing.
Answer: I have tried many different recording approaches with my upright over the past 30 years (and two pianos), both in search of decent tone, and to eliminate extraneous noises— not just from pedals, but also from a pesky bench.
My preferred method is to record from behind, with the microphone [or stereo pair] perpendicular to the soundboard, with the sensing element about 8 inches (20 cm) away.  (My piano is in the middle of the room.)  When using a stereo pair, make sure to use the 3-to-1 rule and keep the microphones at least 8" × 3 = 24" (60 cm) apart.
The tone may not be right for your playing style and preferences, but it gives more clarity and percussion than you might expect.
Answer: I once played in a brand new recording studio and they had a $5,000 "Ribbon" microphone (?).  The tech said he could hear the dampers hitting the strings.  He also heard an airplane fly overhead.  He tried different placements of the microphone and adjusted some filter settings and even the direction and height of the microphone.
Another alternative is to load your sound file into recording software, isolate one of the offensive sounds and the software can find that sound in the entire recording and remove or replace it.
Somewhere on Youtube there is a before and after recording of Oscar Peterson playing in a restaurant and you can hear people talking, forks hitting plates, waiters pouring water . . . then someone filtered them out.  I'm old so I prefer the original.  And, I enjoy pops, scratches smudges and dust in my recordings.
I am an organist and pipe organs are plagued with wheezes, groans, aches and pains of age and they are difficult to record because their ranks are scattered and it is hard not to record the room instead of just the pipe ranks, so for me imperfections are authentic. I don't like hearing the perfection of electronic organs and perfect tuning.
You know, I think in the recording studio, they switched out the microphone to something directional.  Experiment with your settings.
Comment: A ribbon mic seems like an odd choice to me (depending on the musical style)though a good recording engineer can get the most of any gear.  I have some Oscar Peterson recordings  that include the clinking glasses, etc. but I was under the impression that "live" recordings of that era often included separate "room" microphones just for the purpose of picking up ambience to cue the listener that it wasn't a studio recording.  (I also know some artists that add fake crowd noises into studio recordings for an effect.  I'm pretty sure Tom Waits' "In Shades" falls into this category.)
Answer: The problem with the zoom with integrated microphones is the microphones' orientation which is spherical (they catch everything in the room).

You might want to use more directionnal microphones such as cardioïds and super cardioïds.
For the pedal's squeaking, you can use some lubricant such as WD40 on the metal/metal and metal/wood parts. Graphite as powder (eg., from pen) is also a good lubricant for wood/wood.
For pedal's shocks noises, you can add some foam to cushion the shocks AND be careful with your own manipulation of this pedal.
Comment: I'm not using the internal microphones, but foam might be a good idea.

Reduce pedal noise when recording


What is the difference between federalism and intergovernmentalism in the context of the EU?

Question: I get really confused about the difference, it has something to do with the division of sovereignty & power I think and I can't really find a clear answer on the internet.
Comment: As you have looked for information on the internet, you should list what "unclear" information you have found. Otherwise this question is incomplete.
Answer: In a federal system, a single organisation is divided into parts. Each part is given some degree of autonomy. The powers of the local governments are defined and limited by the constitution of the federation: Power flows down from the strong central government to the local governments. Australia, USA, and Russia are examples of federal governments.
By contrast an intergovernmental organisation is a union of several governments. The powers of the central organisation are defined and limited by the member organisations: Power flows up from the local governments to the central government. Examples of intergovernmental organisations are the Commonwealth, ASEAN and the EU.
Of course there is overlap and a fuzzy edge. During the early years of the United States, the degree to which the USA was a federal nation, or a Union of divers states was the central matter of debate. The move to qualified majority voting in the EU gives it more of a federal character, and there are those in Europe who would like the movement towards federalism to be speeded up (and of course plenty who oppose it).
In typical federal systems, the central government has funding sources that are independent of the local governments. In the USA there are federal taxes. Whereas the EU is dependent on contributions from member states.
A test of how much an organisation is a federation is how difficult it would be for a local government to leave the union. There is no mechanism for a US state to leave the USA. The mechanism for leaving the EU is apparently simple, but complex in practice.  For a country to leave the Commonwealth, they just have to say so.
Comment: The first sentence of this answer contradicts the very meaning of the word *federal,* which comes from a Latin word meaning *treaty* or *alliance.*  A federation is formed by mutual agreement among its component parts.
Comment: Etymology is not always a reliable guide to meaning.
Comment: That's true, but in this case it is, at least according to all of my dictionaries.  Your answer is unsourced; can you point to any source supporting your first two sentences?
Answer: To answer your question, I would say an Intergovernmentalism is an umbrella term for Confederate and Federal states, as well as closely working regional standardizations (the most neutral way to characterize the EU is that it's an entity that regulates trade deals among the member states.).  I would argue that EU is more of a very loose Confederation but more on that in a moment.
Federal States happen in one of two ways:  A.) A Government system that is created when a group of sovereign states cede power to a created Federal State (The United States) or B.) the reverse, a Unitary State cedes powers to regional governments but retains some sort of power among them.  At either way, in a Federation, laws that are passed by the federal government are automatically binding for all member states, because the federal government is the member state's deciding representative with regards to that power as a state.
Conversely, in a Confederation, member states typically retain full sovereignty. Typically if the Confederation passes a law, each member state's legislature must recognize the law.  In essence, Confederation level laws tend to be in the form of treaties between the member states, and not laws that pertain to individuals, which are still in the member state's preview.  By this respect, member states of a Confederation retain the right to succeed from the confederation, if they so choose, where as the member state of a Federation does not have this authority (In the United States, the states do not have that right and there was a big War about that contention).  Most Confederations are rather transitional and will become Federations as time progresses (Prior to the Federal State of the United States, its member states were organized under the Articles of Confederation... which were very poorly written and left the Confederation Government with little power to solve the various crisis).
I maintain that the EU is a Confederation because of the nature of their member states with relation to the EU.  The EU does not act as a sovereign externally and the various member states conclude diplomacy outside of the authority of the EU in some occasions.  Again, a distinguishment between confederation and federation is that a member state can secede, as we saw with Brexit.
In all cases, to what level a Confederation and Federation state has power can vary, but the idea is that smaller levels of government typically have more control over peoples lives, where as the larger ones tend to have some control over member state relationships.  For example, the Confederate States of America's constitution was largely identical to the United States Constitution (the big differences were that the President served a single 6 year term, had a line item veto, gave the states the right to secede... and protected the rights of slavery  lets not forget that.) which meant that the National level government had some similar powers to the United States Federal Government.  Conversely, the EU largely retains controls over internal matters, mostly related to trade and movement, and leaves most of the rest up the member states.
Answer: There is one main difference between the 2 systems.
In Federalism, the Federal state is sovereign. And it delegates some of his power to subdivisions that can be states/landers/region. The subdivisions are not subordinate of the federal state. They are at a different level, with different powers but equal in rank.
Typically, the federal state is in control of the army, the foreign policy, nuclear weapons, ect ... The subdivisions typically handle some internal matters. Also citizens living in subdivisions are citizens of the federal state.
In intergovernmentalism, the member states are sovereign and primary actors. They delegate some of their power and resources to the central government.
In this particular case, you can have common foreign policies while countries are still able to have foreign policies of their own.
Citizens are typically citizens of their own countries.
Member states are usually ranked higher than the central government.
One example of intergovernmentalism is Confederation.
In case of the EU, it is debatable whether this still intergovernmentalism or a particular case of federation. There is elements of boths. European law is somehow ranked higher, but it has no army, no real common foreign policies.
Some countries are not pure federation or pure confederation.
The Kingdom of Belgium is officialy a federation, but it has some aspects of a confederation.
Comment: Reading the two paragraphs about federalism and intergovernmentalism in this answer I get the impression that the difference is mostly about quantity of delegated power, not so much about quality, maybe also about perceived ranking.
Comment: @Trilarion  Actually, the main difference is who got the real power and the legitimacy.   Belgium is officially a federation, but Flanders is so powerful, it can make the federal government powerless. To the contrary we saw the catalan division has been overpowered by the Federal State.  As with all governments, the reality of power may be far different from what it is on paper.


How to refresh a frozen bagel

Question: My kids like their bagels like they just came from the oven or the bagel bakery with a crisp crust and soft chewy center. However, it is not practical to make bagels or buy bagels in the morning on school days. What can I do with a frozen bagel to mimic fresh out of the oven?
Comment: Have you tried [F5] or [CTRL]+[R] to refresh it?
Comment: @BaffledCook Are you sure you're not thinking of cookies?
Comment:  that is hilarious.
Comment: Why not keep them in the refrigerator and toast them? If you buy fresh bagels and you eat them every day, they will sure be gone before they go bad in about a month.
Comment: http://www.seriouseats.com/2015/09/how-to-reheat-old-bagels.html
Answer: Buy or make fresh bagels and store them uncut in a plastic bag with the air squeezed out of it in the freezer for up to one month. When you want to prepare a "like fresh" bagel, run it briefly under water (I used filtered water) so that the outside crust is damp but not soggy. Wrap it tightly in foil with a small vent, 1/2" long by 1/8" wide, on one side and heat in a 400°F oven (I use our toaster oven) for about 15-20 minutes, depending upon how cold your freezer is. The bagel will be as soft as it was when it originally came out of the oven and the hot oven will cause the crust to crisp through the foil. Don't let it over bake or it will be rock hard though.
Comment: This is a great use of self-answering to share this delicious technique you've discovered! I will have to try ASAP.
Answer: I understand this is kids, and they like things just the way they like them.  But preheating an oven takes time you might not have. For me I'd defrost overnight in the fridge, then in the morning split and toast them.
To get closer to fresh-baked I'd turn the oven on to a lower temperature (no more than about 150°C/300°F) and put them in almost immediately for 5--10 minutes having just brushed or flicked water on the outside.  If you really want to take them out of the freezer in the morning, 10--30s (for 1 or 2, if doing more try 30s, rearrange, 30s) in the microwave before putting them in the oven will get them defrosted or well on the way.
Comment: Assuming the bagels concerned are affected by staling in a similar manner to bread, you really should _not_ defrost in the fridge. Bread goes stale much faster at cold-but-not-freezing temperatures.
Comment: I think I remember Dave Arnold and/or Harold McGee suggesting you lose very approximately a day of freshness through a quick defrosting alone. Fridge temperatures increase staling rates by about 500% or so on top of that, so I think you're getting the worst of both worlds. Condensation can be effectively addressed by using a bag.
Comment: @David defrosting at room temp means much of the bread is at fridge temp at any given time anyway, so would go stale as it defrosts on the counter.  In the fridge you don't have to worry about condensation making it go soggy.  Wherever it's been defrosted I would treat bread that's been frozen as needing warming or toasting to be nice, and the OP wants to warm it anyway.
Comment: @David (i) The OP is reheating, presumably to deal with staling.  (ii) A bag doesn't help. I know I get soggy bread defrosting in the kitchen in a bag.  Presumably it's water from the bread condensing on the coldest parts of the loaf and then soaking in.  That's worse than stale bread.
Answer: I sometimes do this if I feel really fancy:

Put them into the microwave for a little while (like 20s at 600W for each piece). This will make them soft in the center.
Follow up with a couple minutes in the oven with the top heating element turned to full blast. I actually do this in the microwave as well because mine has a regular heater on top as well. I put the bagels on that riser thingy I got with the microwave, like the one you can see in the following picture:
Answer: Preheat your oven to medium heat, approx 350 F or so, pass your [uncut!] bagel quickly under running water (i.e. don't soak it), and pop it into the oven for a few minutes, like maybe 5. Bagels go through a boiling phase anyway, when they are made, so a little water contact on their outer surface won't hurt them.
Answer: So I actually do this all the time, because my local bagelery only makes pumpernickel on Fridays, so I buy a bunch and freeze them.  In fact, I am about to do this in a few days for our traditional Christmas Morning Bagel Breakfast. After experimenting with several different approaches, this is the one I've found to work best:
Storage: As soon as they are cool, wrap each bagel in aluminum foil (I suggest also labelling what flavor it is with some tape and a sharpie), and then put up to 6 bagels in a ziplock freezer bag and freeze.  The tightly wrapped foil retards freezer-burning, and is useful when you reheat.
Reheating: place the frozen bagels, in their foil, in a 300F/150C oven, which needs not be preheated.  After about 15-20 minutes (20 to 30 if not preheated) the bagels should be thawed and warm.  Remove from the oven, unwrap, slice and eat.
The above technique will get you as close as possible to having a fresh-from-the-baker bagel.  As you can see, though, it might not be ideal for a school morning just because of the amount of time required.  Don't try to speed up thawing with a hotter oven, because that will result in your bagels getting excessively dry and hard.

How to refresh a frozen bagel


Are the Hebrew Scriptures in general to be understood as continuous discourses or fragmental remains of much larger collections?

Question: I often encounter the idea that the Hebrew Scriptures, or at least many of them, are summaries or fragments of larger works. However, considering the value and tight control that the Jews seem to have had in retaining the accuracy of them, it seems more to me that most books are more like continuous writings by single authors.   Is there any evidence that settles the notion one way or the other, or is this a matter of unresolvable conjecture either way?
Comment: Walter Kaiser has a book *Recovering the Unity of the Bible* where he addresses themes appearing throughout the Bible. Also Gleason Archer's *A Survey of Old Testament Introduction* addresses the multiple author arguments of the Old Testament works. To me, they are settled as single author (with a few later edits).
Comment: This has some decent answers already, but the question lacks focus, and some textual examples would provide clarity.
Answer: You might cast a glance at "Peshat and Derash" by Halivni. This book, by an Orthodox Jewish scholar, puts forward the thesis that the original text, as delivered via revelation, had a few mishaps during the era of the Judges, thus explaining some of the more obvious flaws.
Backing up a bit ...
Jewish in-tradition scholarship has always recognized that the text is (a) somewhat pieced together, and (b) has some problems. For (a), see the 'inverted nuns' that bracket certain passages. For (b), see the dots over some words and letters. Halivni's book is a consise place to read up; otherwise the data are scattered all over the place.
Meanwhile, critical scholarship looks to 'the Deuteronomist' as the group of people who assembled a set of disparate textual and/or oral materials into a coherent whole. The overall narrative and thematic cohesion results from this group's desire to reflect their beliefs; the cases of not-so-coherence that gave rise to the original 'critical theory' and its heirs and successors are the result of this group's limited willingness to modify the materials they started from.
I don't find the expressions 'summaries' or 'fragments' to be a particularly helpful way of characterizing the process. If you are {o|O}rthodox, you believe that there was an original text, given by revelation, and subsequently perhaps somewhat damaged. However, 'somewhat damaged' is not the same as 'summarized' or 'fragmented'.
If you are of a more text-critical sensibility, you believe that the text we receive is the result of an intensive literary process that wove together much material. However, the weavers were much more interested in inclusion than exclusion. Yes, some entire texts were not canonized, but the texts we have aren't summaries or fragments.
Answer: Literary structure would be a factor that supports them being single works (with some obvious redactions).
To modern eyes, the books of Moses, for instance, do appear fragmentary, resulting in theories like JEDP. But as David Dorsey observes in his book "The Literary Structure of the Old Testament," the reason for this is literary conventions of which we are not always aware, such as symmetry.
I have done a detailed study on the book of Numbers and it is "fractal" in nature. It is constructed of seven cycles, each of which images the whole. I have no doubt that all the Hebrew scriptures follow the same convention, having covered the basic structure of many of them.
In some cases, this sort of analysis can actually make the "incorrect" textual variants obvious, because they distort the common string of ideas.
Interestingly, Dorsey observes that the book of Isaiah was likely written by a single author because there is a symmetry inherent in the entire text. This would be extremely unlikely if it were written by two authors with a historical gap in between their works.
Answer: there are different authors, and some dispute as to who wrote what. although books written by someone in the story, are usually more fragmented, reason being that it was written in parts, over time. this applies especially to the five books of moses, written over 40 years, (if in fact written by Moses) over which time there were many major events in his life; and some parts he was more familiar with, even experienced first-hand, while others were over a thousand years previous. Lamentations as well was written in two parts, chapters #1,2, and 4, (which all have 22 verses going in alphabetical order) and chapters #3 and 5.
it is precisely because of the tight grip of jews, that we dont have all the books. not because they were lost, but because they weren't included intentionally, as the Babylon Talmud states (megilah 14a):

There were actually very many, as it has been taught, 'Many prophets arose for Israel, double the number of [the Israelites] who came out of Egypt', only the prophecy which contained a lesson for the future generations was written down, and that which did not contain such a lesson was not written. here is a link its on page 52

(for those who dont know 600,000 Israelite's exited Egypt = one hell of alot)
Comment: here is what i said "it is precisely because of the tight grip of jews, that we dont have all the books. **not because they were lost,** _but because they weren't included intentionally_"
Comment: There are some indications of books being written (i dont have a good source sorry) and not accepted as mainstream, i.e. part of the 24 books. i think there are some in other traditions, and/or discovered somewhat recently, im very sorry that i dont have a good source for this. you may want to google this.


How to film a moving bike on a budget

Question: I have been tasked with filming a new road bike for casual cyclists. We have a rather low budget. Does anyone have any tips on how to deliver quality footage without spending too much money? I'm am using a Canon 5d Mark III SLR to shoot. I'd appreciate some tips on how to get good wide and detail shots while the bike is moving.
Answer: Here are some suggestions:

Film the bike from a moving car.
Have two people in the car, minimum: One for driving and one for filming.
Shoot through open windows of the car, not through glass.
Get every shot from every angle you need separately.
Do all of your editing after recording, not in camera, using video editing software.
Comment: Do you have any tips on how to stabilise the camera in a car on a budget?
Comment: If budget is really low, than I will advice a stadicam and record with bigger resolution, to stabilize in post-production. But pot-production stabilization can "eat" a lot of footage, so don't really count on it, if shot is too shaky
Answer: Something that might make your life considerably easier is a gimbal stabiliser.

These let you get good quality moving shots easily, without the bunmpyness that you'll get even in a car. I worked on a shoot where we even filmed a skateboarder with the camera operator on inline skates (he was a pretty good skater though, wouldn't suggest it if you're like me).
They're not super expensive to buy, but if you don't want to be buying gear you could hire one. For the time it will save and the added quality it will give it's well worth it.
Comment: Thanks yes i had thought about hiring something like this but wasnt sure if it was overkill but they do look pretty cool and arent that expensive to hire. Are they easy to use and setup. I have tried stadicam ones before but were a night mare to balance
Comment: We have that model where I work. The learning curve is fairly low, mainly it's getting used to how it steers. An off-board monitor for the camera is really useful, because with the gimbalarms in the way you aren't able to see the camera's LCD very well, so it's worth getting one. They look like a cool gadget, but they're actually a very useful addition to the kit.
Comment: i took your advice on this and the results were phenomenal great piece of kit which you can see here https://www.youtube.com/watch?v=TPbWp-p_zlo&t=7s which if you have any feedback would be good. Just a general query that you may be able to help with. Have you ever used one in adverse weather conditions such as rain and how do i protect it and the camera
Comment: I'd be wary about using it in the rain. Just guessing but I'd say it is not very weatherproof at all. I'd ask as a separate question, someone might have experience of this.

How to film a moving bike on a budget


Is it possible to predict the orbital shape with the given kinetic and potential energy?

Question: Is it possible to predict whether the orbital of the object is circular, elliptical or hyperbolic only with the help of potential and the kinetic energy of the object is given.
Answer: Yes you can, and it's really easy. Assuming that you have taken the reference level for 0 gravitational potential at infinity (this is quite standard), then, if KE+PE is positive, the pathis hyperbolic. If it is negative, it is elliptical (or circular1). If it is zero, you are at escape velocity and the path is parabolic.
In a hyperbolic path, the object has enough total energy to reach "infinity". So, KE+PE>0. When it is equal to zero you get a parabolic path, because it still has enough energy to reach infinity, but just enough (and a parabola can be looked at as a limiting case of a hyperbola lobe). If it is less than zero, it does not have enough energy and will eventually "turn back", giving a elliptical orbit.
Here's a simulation (I've taken some of the quantities to be equal to 1 for simplicitly):

(Note: The image seems to become a parabola before it really does at -0.04 total energy because there isn't enough space to show the large ellipse)
1. If you wish to determine whether or not the orbit is circular, you need to know the mass ratio and the angle the velocity makes with the radius vector
Comment: @DeerHunter Well, the diagram was drawn for free space. Putting even another star nearby would change this as the shapes won't be so simple. Also I was considering the system to be Newtonian. With a black hole, you're considering a relativistic situation, which means that potential isn't exactly defined. Though I think you can define it knowing the metric, and with that definition the "escapes"/"doesn't escape"/"just escapes" thing will still hold, however the shapes won't be conic sections (and will also depend on your reference frame)
Comment: Does being in the vicinity of a black hole change this?
Answer: the difference between the kinetic and the potential energy is H
$$H = T - \left. {\left| \phi  \right.} \right| =  - {1 \over 2}{{{k^4}m} \over {{h^2}}}(1 - {e^2})$$
solving for e:
$$e = \sqrt {1 + {{2{h^2}H} \over {m{k^4}}}} $$
which shows that if H

negative then e<1 (the trajectory is ellipse)(kinetic energy < potential energy)
positive then e>1 (the trajectory is hyperbola)(kinetic energy > potential energy)
equal then e=1 (the trajectory is parabola)(kinetic energy = potential energy)
Answer: Okay, so let's take a look at what you actually have with kinetic and potential energy. For simplicity's sake, let's assume you only have gravitational potential energy.

Kinetic Energy = $\frac{m v^2}{2}$
Potential Energy = $m*g*height$.

Okay, so given those two terms, what are you missing? What you really need to know to determine an orbit is a position and velocity, having both will give you the orbit. Alternatively, multiple positions can give you the same thing. So, what do you still need?

You need to know the gravity to get the height.
You need to know the direction to get velocity (Energy is scalar, it doesn't have a direction)
You need the mass of the object.
You need position other than height.

You could form a partial orbit with two bits of information:

Gravity (Specifically, g(height)) If orbiting Earth, this is easily known.
The mass of the object.

This will give you some, but not all, of the Keplerian elements. Specifically, you could get eccentricity, Mean Motion, and Mean Anomaly, but you can't get inclination, Right Ascension Node, or Argument of the Perigee.
Answer: If you are considering only two objects and want to determine whether one object is in an orbit with respect to the other, you need to know:

The combined mass of the two objects in question
The position, at some point in time, of the object in question, with respect to the combined center of mass of the two objects
The velocity (vector) of the object in question, with respect to the combined center of mass, at the same point in time you determined its position.

It's not really about knowing the kinetic and/or potential energy of an object as such.


DHS public trust clearance

Question: One of the TOP ten government contractor applied for DHS Public trust clearance for me. It took about 5 months for approval. By that time clearance being approved, I joined another job which does not required clearance. So I declined the job. I'm thinking to go back as government contractor again. My clearance was approved two months ago, I'm wondering whether I can use that clearance to join another company as a contractor.
Comment: This [document](https://fas.org/sgp/othergov/dhs/persec.pdf) may be relevant.  Among a other things, it says "Agency
clearances are terminated when an employee permanently leaves
the agency; however, the new agency may use the background
investigation already performed by the former agency to issue a
security clearance"; which I take to mean that you cannot reuse the _clearance_, however you can reuse the _background check_ that was performed to get a _new_ clearance.
Answer: From what I can gather here and here, security clearances aren't tied to you as an individual, they're tied to your role at a particular employer (where said role warrants/requires a security clearance).  There's a small caveat to that if you're an independent contractor who's working on/bidding for government contracts, however even then your clearance is only technically granted within the scope of a particular project (or set of projects).
On that basis, I'd say the answer is no, you cannot reuse the clearance.  That's something that was issued in the context of you performing some specific role for a specific government contractor, and it doesn't carry over to a new employer.
However, you should be able to reuse any information that was collected as part of the background investigation that was used to determine whether or not to grant your security clearance originally, provided the information itself hasn't expired yet.  That may make getting approved for clearance with the new employer faster/easier than the initial process.
Comment: I don't know about DHS clearances, but DOD clearances are "active" (their term) for a period of time after you leave the employer who obtained it for you.  If, during that window, you join another company that needs you to have a security clearance, it's easier to get it transferred (compared to starting over with a new application).

DHS public trust clearance


How to create a site collection

Question: I need to create a site collection so that url looks like http://hr.mycompany.com instead of http://portal.mycompany.com/hr. How do I do that?
Answer: What you're looking for is the host named site collection, which enables you to assign a unique DNS name to site collections. Or alternatively create an AAM for existing Site collection to achieve it. For example, you can address them as http://hr.mycompany.com or http://sales.mycompany.com.
The sample PowerShell code creates a new web application listing on port 80, and two host named site collections that use the Publishing Portal site template.

Create a web application to host your host-named site collections
$w = New-SPWebApplication -DatabaseName "WSS_Content"
    -ApplicationPool "SharePoint - Content App Pool" -Name "HostNameTest" -Port 80
Perform an IIS reset
IISRESET /noforce on each server before using the new web application
Create a root site collection
This is required for Search crawling content. For more information, see: http://technet.microsoft.com/en-us/library/cc424952.aspx#section2b
$webAppUrl = "web application url" #ex: http:// sharepointserver
New-SPSite $webAppUrl -OwnerAlias "SP\someusername"
    $w -Name "RootSC"
Create your site collections
$w = Get-SPWebApplication "HostNameTest"
New-SPSite http://hr.mycompany.com -OwnerAlias "SP\someusername"
    -HostHeaderWebApplication $w -Name "HostA" -Template "BLANKINTERNETCONTAINER#0"
New-SPSite http://sales.mycompany.com -OwnerAlias "SP\someusername"
    -HostHeaderWebApplication $w -Name "HostB" -Template "BLANKINTERNETCONTAINER#0"

So, you will have a web application with two two host-named site collections.
If SSL is a requirement, you can also create the web application and the host-named site collections using https (ex: port 443). But you will need to buy a wildcard certificate or a SAN certificate for *.mycompany.com. Also note that SSL is a requirement for certain features of SharePoint 2013.
To find more information:

http://technet.microsoft.com/en-us/library/cc424952.aspx
http://blogs.msdn.com/b/kaevans/archive/2012/03/27/what-every-sharepoint-admin-needs-to-know-about-host-named-site-collections.aspx
http://blogs.technet.com/b/speschka/archive/2013/06/26/logical-architecture-guidance-for-sharepoint-2013-part-1.aspx
Comment: Assaalamualaikum. Can you provide details on how to do this using AAM?
Comment: WSalam, before you plan to go ahead, you need to make sure that AAM is configured correctly. The reason is when SharePoint receives a request it will only use AAM to perform that URL resolution. So while it is necessary to make sure your hosts files, DNS, and IIS bindings are properly configured so that a web request can reach the SharePoint server, it is also necessary to configure the URLs in AAM to match. See the link to try it yourself: http://sharepoint.microsoft.com/blogs/fromthefield/Lists/Posts/Post.aspx?ID=8
Answer: You need to create a new web application and specify this as the URL, yes you could use an existing site collection an extend it using AAM but if you are starting from scratch a new web app and site collection is best.
Thanks
Matt
Answer: Specify the host header what you want it to look like while creating new web application. or you can always use Alternate access mapping to look like http://hr.mycompany.com.

How to create a site collection


Is the second 'T' silent in "petites" ?

Question: In this video, around the 0:41 mark, the man speaking pronounces petites with the second t lost to a liaison. Is that a regional affectation, or did I just never know this? If this is standard, what is the rule that causes that to be silent?
Answer: The man actually pronounces the second t. Even though it is not as clear as the sounds from the beginning of the word, I distinctly hear it. If you play the video at half-speed, you can hear it being merged with the z sound of the s liaison, PETI-tZanimations.
In standard French, the t in that phrase is not silent.
Comment: Exactly, on the contrary in those cases the e is always muted.
Comment: The e would be pronounced by most speakers in contexts like « petite housse ».
Comment: @Walfrat You got me thinking : most of the time in casual conversation the e is muted but I'm not entirely sure it is a strict rule. I have a song in mind where it clearly is not muted : "Petite Marie by Francis Cabrel". Altough it might be an artistic decision.
Comment: @Benoittr: singing and poetry are a special case.
Answer: The second /t/ is not lost. It's there, but it merges with the following /s/ (which, itself, is voiced into a /z/ because of the intervocalic context). So in the end you have /pətitzanimasjɔ̃/.
Answer: With the e (or es as here) at the end, the t is pronounced, maybe not forcefully, but still there. as already stated, the liaison is more between the s and the following a, so the t sort of gets lost.
Answer: I did not watch the video.
It depends. In French, the masculine form of the word is petit (no e at the end). In this case, if the word after "petit" starts with vowel, the "t" would be pronounced (i.e. un petit arbre). If the word after "petit" begins with a consonant, the "t" would be silent (i.e. un petit gateau).
The feminie version (petite) does not have this peculiarity, since there is always a vowel (petite) after it.

Is the second 'T' silent in "petites" ?


I don't have batch entry of contributions - why?

Question: I don't seem to have the "batch entry" feature in our Civi database.  When I go to the Contributions drop down where it should appear, it's not there.  Does this mean I'm running a downlevel version of Civi and if so, how do I find out what version I have?  Thank you.
Answer: you can find the version of CiviCRM at the bottom of any CiviCRM page
it will say
Powered by CiviCRM 4.6.5. CiviCRM is openly available under the GNU AGPL License.
Please try to install the latest version of Civicrm which has the feature


Is there a way to have my second action animation start at the last location of my first action animation?

Question: I have a scene with a character that will complete multiple action animations. The problem I keep running into is that when the character transitions from action 1(walk) to action 2(looking behind) the character slides backward to action 1's start origin. Is there a way for me to have action 2 start at the end of action 1's animation. I've tried moving the character while in object mode and recording in the timeline but it changes the origin location of action 1 animation.
Answer: For anyone with a similar problem to mine, I found the best way to resolve this issue is by adding a path for my character to follow. Using the shortcut Shift A, and selecting the Path option under Curve. I completed these steps in Object mode. I suggest searching for videos on how to create a path for walk cycles if you need further help with that step, I found many great resources on youtube.


Rear Derailleur Curled Up

Question: I recently bought a bike for the first time in 10 years and after riding it for a couple of days the rear derailleur curled up like an insect ready to die. Is there any way I could fix that or am I gonna need a new shifter?
Comment: Have you got a photo? The description could be anything from just needs your chain length adjusting a bit and/or learning which gear combinations to use to being totally broken. (With intermediate "can be unjammed if you are careful, then adjust/learn so it doesn't do it again".)
Comment: It sounds like you just got both derailers on the smallest cogs.  This causes the rear cage to fold up, trying to keep the chain taut.
Comment: when you have the chain on both largest cogs if the dérailleur is still too far back the chain is just too long
Comment: Is this a new bike or a used bike? I don't normally say this, but I think a trip to your local bike shop will provide you with some much needed pointers to get you back in the game. It might be that you're not using correctly as Daniel suggested, or it may be any number of things depending on how old the bike is.
Comment: I bet you just have to adjust the chain length to be the right size.
Comment: A picture would be nice, but it could be a broken shift line, which then, as the bike was pedaled, would let the derailleur move to it's smallest position.
Answer: If the derailleur still shifts normally, you may have nothing to worry about. It sounds like it could be a few things:

Does your rear wheel sit in a dropout, or is the length of the wheelbase adjustable front to back? If it's adjustable, it's possible that the wheel skewer bolt got loose and allowed the rear wheel to slide forward, causing excessive slack in the chain.
Your chain somehow stretched dramatically
The spring in your derailleur is shot

Rear Derailleur Curled Up


HP Rapid Deployment - Change Data Store Path

Question: I am running HP Rapid Deployment (Altiris eXpress Deployment Server 6.9 - Build 164) on an inherited Windows Server 2003 SP2. I need to change the Data Store Path as the default is pointing to the C: drive and there is not enough space there. I would like to set it to the D: drive where there is plenty of space.
Reading the documentation:
Data store path:
Specifies the path to stored packages and files and other DS functions (such as license verification). The default path is C:\Program files\Altiris\express\Deployment Server.
Note:
Do not use this setting to change the path to the Deployment Share. Modifying this setting does not automatically allow you to use another shared directory other than the express share. To change the Deployment Share shared directory, run a Custom install to establish another location for the Deployment Share.
Is there any other way I can change the path as I do not have the install media?
Answer: managed to find the answer:
https://kb.altiris.com/display/1/kb/articleContent.asp?aid=33382&n=1&s=&link=


Which is water shut off valve here?

Question:
I need to shut valve to fix bathrooms
Comment: Can you provide a picture from the right side?
Answer: This appears to be the plumbing for your water heater - as such, while there are shutoff valves for the cold into the heater and the hot out of the heater, the cold running to your various fixtures (and to here - the main water shutoff) is almost certainly somewhere else.
The water shutoff valves here are the red and blue metal handles that are shaped somewhat like:
<code>-\_/-
</code>
Turn them 90 dgrees so the handles are out of line with the pipes they are on, not in line with them to shut off - reverse to turn on.
Check your water heater manual to see if you need to shut it down before turning the water off. That's pretty common.
The other red and blue handles near them appear to be for some sort of flushing procedure with the capped ports near them.
Comment: In summary, you can only turn off the HOT water supply to the bathrooms at that fixture.
Comment: Very likely the Blue is the cold inlet to the water heater.
Comment: Ecnerwal is correct the tankless water heaters tend to have mineral buildup on the heat exchanger and some water systems require at least annual flushing others more often. Make sure the chemical you use is safe for your unit some acid based cleaners will quickly wipe out an aluminum heat exchanger.
Answer: Typically the water SUPPLY shutoff valve is on the outside of the house, where your water comes in from the source (utility, well, tank etc.). Closing that valve is what you need to do if working on ANY of the plumbing in the house, otherwise water can flow back through other things.
Comment: Not in freezing climates, where it is far more commonly inside the house, in the basement - though in some places it's outside the house, in a deep hole and the utility needs to shut it off for you - which is inconvenient enough that most houses have an internal main shut off even if there is a curb valve. For pumped wells, you can also just shut off the power to the pump and release pressure, but there is normally a shutoff valve as well - and in freezing climates that is almost always inside the basement.

Which is water shut off valve here?


Portable air vent

Question: Can I vent a portable air conditioner thru a wall sleeve? Will it vent properly? I have no air conditioning and don't want to spend a ton on a in wall air conditioner..
Answer: Do you already have a wall sleeve installed? if so you could vent a portable ac through it but most of the time they are designed for a window unit so it is the typical small rectangle wall sleeve I would recommend finding an window unit for it. That will work a lot better in the long run and should be cheaper to buy.
If you are thinking about installing a wall sleeve it would be perfect ventilation for a portable AC if you already have one.
Answer: I cannot see any problem putting the exhaust tube through a wall sleeve.  I have seen crude use of an open window to put the exhaust tube through (closing the window onto the exhaust tube to hold it there) which to me is not as efficient.
As long as the exhaust tube fits inside the aperture it will be adequate for the purpose.
Comment: I live in an apartment that already has the sleeve installed.. I am hoping that would be adequate ventilation.
Answer: You can exhaust a portable through the wall but remember you need fresh air to be able to enter the home. Many newer homes are sealed quite well and pushing the hot air outside with out a vent to allow air to enter pulls hot air from the attic access in many cases. I have had home owners say the air will come in the bathroom or kitchen exhaust vents but both should have back draft dampers that prevent air from going backwards. A chimney usually will allow enough air entrance but this can cause odors in the home. If your furnace hose a make up air or fresh air port it would be fine to exhaust the portable through the wall. Make sure to check for live electrical in the wall prior to drilling (many stud finders have a live circuit detector and you really don't want to drill through a stud either.
Answer: If it's an apartment shouldn't the landlord fix the ac? Have you thought about just buying a window ac and putting it in the wall sleeve? You can probably get a window ac for the save price, or close, as a portable one.

Portable air vent


Seeking historical traffic data matching OpenStreetMap dataset?

Question: I'm using San Francisco dataset offered by OpenStreetMap and I'm trying to get the optimal path using the pgr-astar function of PostgreSQL.
I want to find the historical traffic data of San Francisco roads (roads congestion with time slots), that corresponds to the format of the dataset generated by the map so I can calculate the optimal path based on the historical traffic information of each road segment.
Where can I get this data?
This is the dataset of San Francisco, where a road is divided into many segments.

I found many sites that offer the traffic information but it doesn't match my dataset ( without accurate information of the road segment).
Answer: You are going to need to process the data yourself. This type of data isn't collected against osm because there is no guarantee of consistency
Comment: How does osm provide "guarantee of consistency"?