Am I too late to be a professional in chess?

Question: I am at the age of 32 and my current rating is 1600. Is it too late to be professional in chess? I love chess from my whole heart, what should I do?
Comment: Some people have this level at 10, dedicate their lives to chess for a decade, reach GM, reach a 26xx rating, and then don't become professional because that simply isn't good enough to be professional. You need to be in the world top 100.
Comment: This question has been asked several times before - https://chess.stackexchange.com/questions/21641/what-age-is-too-old-for-becoming-a-good-international-tournament-player, https://chess.stackexchange.com/questions/6315/can-i-improve-my-chess-or-am-i-too-old
Answer: Sorry to put this bluntly, but you have absolutely no chance whatsoever of becoming a professional player if you are rated only 1600 at age 32.  This is not a realistic ambition.  People improving from 1600 to grandmaster level in their 30s and beyond is something that simply never happens.  It's very rare to reach grandmaster level if you are only 1600 at the age of 18, never mind 32.
Answer: Assuming you want to be paid enough to live I am afraid it IS too late. Younger minds are easier to be taught. You develop much faster when you're younger. But hey, that's a good news! Professional chess players spent long years, lots of money for coaches, tournaments etc. Now, 99% of them earn pennies - how frustrating!
This is a very brutal truth, chess is a beautiful game that requires a lot of work, austerity, time and in return there's... the satisfaction. I am very happy that I got to know chess and dedicated my young years to it. Chess taught me really a lot. But I would advice against dedicating the whole life (professional).
However, if you want to make money with chess, in my humble opinion, the best way is to teach kids - it doesn't require that much chess skill, rather more of a pedagogical attitude. I am pretty sure you are able to do that.
Answer: Most chess "professionals" teach.  You might be qualified to teach kids the rules.  There are plenty of bad chess players that make a living teaching kids.  So, if you go that route you can work on your game and scrape a living teaching.  And maybe one day you might actually be qualified to teach, but you are unlikely to even make master.
Comment: If you look at the percentile that masters fall in (99.98%), they are in the top 0.02% of players.  Of course it is possible to achieve this at most ages, but a lot of stars need to line up when you are 32.  Besides a love for the game, you need talent, dedication and a lot of time.  Also, there is the sporting aspect of the game that requires physical fitness... "unlikely".
Comment: Unlikely to even make master? I like the style of your answer. I like the way you think, but are the prospects actually *that* poor? (I ask for a personal reason, because I happen to have nonchess credentials similar to those of the typical chess master, but never tried to improve my chess to such a high level because, well, there is an opportunity cost, isn't there? I would rather study a book on, say, the mathematics of special functions than a book on QGA. Now in my 50s, I accept that I am too old to become an IM even if I tried, but OP is only 32. This is why I ask.)
Comment: I suspect that you are right. Indeed, I had not known that masters were so extremely elite: 0.02%! (Interesting. I had always vaguely, or at any rate vainly, supposed that I might have made IM if that had been a goal of mine, but 0.02%? That is too elite. You remind me that I am not that smart. It is a good reminder. The illumination is appreciated.)
Answer: If you mean "professional" as "making a living" (earning money) -- your chances are quite slim. You need to hold a title (GM, IM, WM, CM, etc) to play money-earning tournaments or to be considered as a professional chess coach.
Besides that, since the invention of the chess computers, the chess (as a game) is currently in decline, less interest from the people, less money involved, etc. You'll be fighting for your chance with the already established people and there are just too many of them to fill the available spots.
What should you do? -- Just have fun. Learn to play better, play with people, enjoy chess as much as you can. It's just a game after all =)
Comment: *"the chess (as a game) is currently in decline, less interest from the people, less money involved"* -> source needed !
Comment: To be a titled player you need to have some ELO rating, norms and stuff. That requires skill which requires time and money. To be GM/IM very long road. To be CM - I'd guess like 3-4 years and you're there. But CM is nothing.
Comment: If you're 10 and gifted, you may get to IM title in a few years. After 30 things tend to take longer. I would say, as a baseline, you need to invest about 10k hours into chess (or anything else, for that matter) before getting any recognition.
Comment: thank you sir.But what is the preparation to hold a title(GM IM WM CM)
Comment: @Pijotrek: saying 3-4 years is misleading, the vast majority of chess players never reach that level in their lives.
Comment: @RemcoGerlich well, it depends on your definition of a "chess player". I think, for an average John Doe, 3-4 years is more than enough to become a CM (assuming he has time, money and willingness to learn).
Answer: I'm kind of with the others that have stated it is too late.  Only because of the examples of the top players and how basic research shows how long they've been playing and the talent they've shown their entire career in chess.  They are the examples of what it takes so to put it bluntly, if you aren't on that same path then there's a strong chance that when you are in your 30's and your not there, may not happen.  Becoming a teacher of chess is probably more obtainable goal.
Think of how the game has changed.  You have to be prepared for the increased difficulty in the game due to chess engines and AI.
Here are some areas I think are good to consider for your own life and your ability to accomplish them.

Become a FIDE member
Score the required norms in FIDE registered tournaments and the norms can be defined by the specific tournament so you may not know what that "norm" is until the tournament.
Pay for the expenses of those tournaments.  Entry fees, lodging, food, transportation.
Reach the 2500 rating to become a grand master.  The money that takes to jump from where you are at, my prediction could be steep, specifically with preparation so you can beat the competition out there because you are not the only one dreaming to become a professional chess player.  A 900 rating jump is not a mole hill to climb in the world of chess. The complete expenses of the tournaments to get your rating up.  The chances are low that you going to get much return financially in the process in the beginning.
The personal time that is needed to invest into getting to that point, do you have?  Do you have obligations in your life that are more important than chess?  Most people do.

Not meaning to squash your dreams but there's quite a bit to take in to become a professional chess player.
There's no shame in being in your 30's and a rating of 1600 or teaching chess to people.  You never know, you could be a part of the process for someone else to be one of the top ranked players.
However if you choose to seek becoming a professional player I do hope the best.  Here's a link to FIDE's for Title Regulation effective July 1st of 2017 to give you more detailed answers.
http://www.fide.com/fide/handbook.html?id=198&view=article


Can places be assigned to a whole folder (and subfolders) in aperture 3?

Question: I recently took several thousand pictures in India. As a shot I was placing them in folders by location. When I retured home a started using Aperture 3 (first time with Aperture). I imported the project with my original folders. I would like to be able to assign locations via Places to take advantage of the mapping functions. I would assign ALL PHOTOS by the parent folder to India and the SUBFOLDERS by city or region. Is this possible? and if so, how do I do it. I do not have GPS data so I must manually apply places.
Answer: Aperture retrieves a hierarchical database of places from the net as you use it. This breaks down each place into countries, states, cities, and places.
As a result, you should only need to assign places to each local group of photos. This should allow you to use the path navigator in the Places tool to select all photos in a given country or region.
To assign places, go to the Places tool and zoom into the area you are interested in.  Select one or more photos and drag them to a point on the map. If you're happy you have the right point, click the Done button, and each photo should be marked with a small red pin icon.
For example, if you have a folder containing all photos in Mumbai, you can drag those photos to Mumbai in the map in the Places tool. Similarly, any photos taken in Hyderabad should be dragged to the map. You should then be able to ask the Places tool to show you all photos in India, which should include both of those groups of photos.
You can also then create a smart album for a particular area of the map:

Scale the map so it only shows the area you're interested in. You can do this by holding down the command key and dragging a selection rectangle around the pins in your area, or by just zooming and panning the map.
At the bottom of the map, click on the Action menu button (looks like a cog). Choose "New Smart Album from View"
Rename the Smart Album to be something suitable (e.g. India)

Alternatively, the Smart Album HUD allows you to choose a specific place.

Create a new Smart Album
Click on the Add Rule menu and choose Place
Select the Place checkbox and type "India" (or other place name known to Aperture)
Name the Smart Album as appropriate


drop of water on mousepad of macbook pro and now the mouse is being odd?

Question: I had wet hair and some drops of water landed on my trackpad. It happened on last friday or thursday, so like 4 or so days ago. And basically now my mouse will just randomly click on stuff and right click too and for the first couple hours I couldn't use it and I wasn't able to get it to work except for the top portion of the mousepad. and now It's no longer that bad, but it still randomly clicks and moves around. should I take it to a genius bar or do you think it'll just eventually stop? any help would be really appreciated and sorry I know this has probably been asked a hundred times.
Answer: This sounds like you may have liquid damage to the system. If this is the case, the issues won't just go away. Water-based liquids are very corrosive to electronics and the damage cannot undo itself. However, you can certainly take it to the Genius Bar. However, I wouldn't mention the water droplets to them. If they can't visibly see the liquid damage and can confirm the issue (and provided you are under warranty), they may replace the trackpad piece free of charge.


Do transactions affect the discovery of a block?

Question: When a miner creates blocks, do transactions in that block affect the result? For example, if a miner creates a block, but now a new transaction is broadcast on the network, will the miner stop current work, then add the new transaction as one of the inputs, then recreate the block?
Comment: You can't "recreate" a block. If it has different transactions, it's a totally different block. When a miner mines a block, they'll start on the next block, typically including all transactions that are valid for inclusion at that time.
Answer: There's no such thing as 'aborting'. It's all random anyway. The chance of solving a block on the first try is equal to the chance of solving one on the 1000th try.
It's like the difference between picking the same lottery numbers all your life or picking different ones each week. There is no difference.
Answer: The miner won't stop the hash generation of their block. Even with new transactions coming in, they'll add them to their block until the hash is found. It could happen with only 20 transactions or with 400. The difficulty is so large that it's pretty random. So it's not like they get a set of transactions aside and work on those. They keep on working as transactions come in until they find the hash.


Would it be weird to cold email former students of a prospective advisor?

Question: I was accepted to a PhD program, and the two professors I mentioned in my application have reached out to me to discuss research. Now I am wondering what is the best way to gather information on them. Is it considered odd to cold email a recently graduated student from the program? Or current students? I'll likely be in the same community as these people for awhile so don't want to be considered strange ...
Basically, almost all the PhD advice I've come across stresses the importance of talking to an advisor's students. But how do I contact these people? I will be visiting the school but am not sure I will have time to both meet with all of the faculty I'm interested in and their students.
Comment: At what point do you have to choose an advisor?
Comment: The initial assignment seems to be made quite early (before matriculation), and then they must confirm it by the end of the year.
Answer: This is an opinion and you may get opposite opinions, of course. If it is weird, it is only a little weird. I think it is something worth doing, actually. "How is Prof X to work with? Does s/he provide a lot of help or only a little. Any thing I should be aware of?"
There is very little worse in doctoral education than having a poor or abusive advisor. All you really need to know is that they treat students appropriately, even if they are (very) demanding.
You can find a lot of horror stories about advisors by searching/browsing around this site.
But just keep it informal.
I don't recommend cold calling professors, but would treat calling students differently.
Answer:
Is it considered odd to cold email a recently graduated student from
  the program?

This is sometimes encouraged by the professors themselves. When I was applying for a PhD, a professor told me to contact his current student should I have any question about the lab, the school, the city and so on.
Back to your question, I think it's good to contact former PhD student. If they had a very good or very bad experience, they would be very eager to tell (or complain to) you.
In many countries, e.g. US, UK, the PhD theses are publicly available for download. And you can have some information from the Acknowledgements in their theses.

Did they thank their advisor passionately?
Did they thank their advisor for "always being available for discussions" or "allow them the freedom to do their research", or just "introduce the problem". You know the implications.
Did they thank other people in the lab, in particular fellow PhD students?
...

If there is no acknowledgement, that's the worst.
Comment: I doubt the details of the acknowledgements section of a thesis are all that informative.
Comment: @Dawn Interesting. I just wouldn't trust that people put that much thought into the message their acknowledgement conveys, especially when people who are afraid of their advisor are still dependent on letters of rec etc around the time they are writing their acknowledgment, and people who trust their advisor a lot aren't worried about brief praise being anything but genuine. I just think an informal conversation is much more likely to be fruitful.
Comment: @Bryan, I actually think the exact opposite. I know students with poor advisors in my program typically thank the advisor in very cold and formal language. This is a great suggestion in my book.
Comment: This is the only answer that doesn't imply that it is weird to contact former student. It is certainly NOT weird! I've been contacted and I've answered very honestly. The idea of looking at thanks is dissertation is interesting, but conversation/email is better.
Answer: It's a little weird but understandable why you want to do it.
If you could sidle up to it a little, I advise that.  Start with current students and do the discussions one on one (and not written, telephone or in person).  Ask a set of general questions (field, department, university, town) and include the advisor relations question(s) as a subset.
If you contact previous students, I would send a general email (thinking about doing research in X subfield, like to get your perspective) and ask to have a conversation.  [If you know there number, I would go direct to a phone call...leave a composed, short voicemail.  If you get them direct, just ask for a time to talk to them (so it is not sprung on them to consume their time immediately.]  Then same advice for current students as before applies.  Ideally, you may have some point of contact with the old students (shared network, same undergrad, etc.) to make it a little less cold.  But given you are not hitting them immediately with the questions, just the request to talk, I don't think a cold outreach is unreasonable.
Answer: I feel the other answers are not stated strongly enough.  Yes, it is weird, but you should absolutely do it.  You can use this method of cold-emailing:

Subject:  Your work with Prof. X
Dear Dr. ____,
I am contacting you because you were a student of Prof. X.  I am
  considering joining the group of Prof. X at ___ University.  I would
  like to get a PhD in (specialty) and pursue a career in (whatever
  industry).  Do you have any advice for me?
I will keep your advice confidential.
Thank you in advance
Your name

Generally when I do this I get a prompt response telling me how wonderful Prof. X is.   If you get other results, do not work with Prof. X.  While you are doing your cold-emailing, take note of the jobs Prof. X's students have.  Are those the jobs you want?  If not, find an advisor who can help you get those jobs.


Mac OS X Finder: show just file details

Question: The Finder in column view shows a preview of the file, then information listed below it. The preview (which has no value to me) takes up most of the available space and the file information I want to see is hidden.
All I want to see is the size, creation and modification dates. I would also like to get rid of the "more" section, which is useless and just takes up space.
In the image below, the preview takes up most of the space, the "more" section takes up nearly 1/4 of the space and of the 3 things I want to see most, only the size is available. The name and filetype is already displayed on the column to the left, it's pointless to repeat it under the preview.

I know I could switch to the list view, but I've used the column view forever (since 1990) and it was extremely useful, now it's just a daily annoyance. I also don't want to have to navigate to directory using one view, then switch views to select a file, then go back to column view to navigate, etc.
I'm not a fan of Windows, but I find I can configure Windows Explorer to suit me much better than the Mac OS Finder as I can get rid of the preview and show just the information I want.
Is there any way to do that in the Finder?
Answer: In Finder, select View → Preview options. This displays a dialog.

Turning off all options except the couple that I want means I now have the view I want.
Comment: Yeah - it took me *forever* to find & get rid of the "Show Quick Actions", which was nothing more than a useless box hiding half the info :\

Mac OS X Finder: show just file details


Mac Application to defrag my Mac drive

Question: I work on media files as per my profession. I find my Mac (Mac Lion) going slower day by day. I think it will be beneficial to defrag the drive but didn't find any Apple tool for it. I want a an effective third party Mac defragmenter for my Mac drive.
Comment: See also: [Do Macs need to be defragmented?](http://apple.stackexchange.com/questions/829/do-macs-need-to-be-defragmented)
Comment: It is not entirely answer to your question, but you can solve this problem switching from HDD to SSD that not required defragmentation.
Comment: @WojciechBednarski Every hard drive suffers from fragmentation. SSDs have a extremely fast access time compared to mechanical drives, therefore it is less visible. SSDs have a limited number of read/write cycles for each one of it's cells, you win some, you loose some...
Answer: Speed of access on HFS+ drives is not that affected by fragmentation unlike Windows file systems as OSX will do some defragmentation. A third party investigation is here.
You might be better off checking there is enough free space for new files.
There are some utilities to do defragmentation like iDefrag
Comment: I agree about free space. Having enough affects speed quite a bit. Having enough memory also affects speed as OSX uses disk swapping when memory gets tight, slowing things down as well.
Answer: On APFS - you don't need to defragment anything.
On HFS+ - DriveGenius does what you ask. It rebuilds the catalog (filesystem) that tracks the files. You don't need to rearrange the files on the drive as macOS does that for you - just keep 20 GB free or 25% free if you can, and the system optimizes the file location automatically.

There aren't many apps that do this on mac since actual filesystem fragmentation both rare and rarely a cause of measurable slowdown.

Mac OS X automatically defragments files that are likely to cause a slowdown in addition to automatically optimizing hot (often used) files to a fast and not-fragmented part of the drive.
The HFS+ filesystem directory / catalog itself can become fragmented over a long time but you can fix that easily. Back up to time machine and an erase install / migration back cures that issue without needing to spend money on a live tool. DiskWarrior also helps to rebuild HFS+ catalogs in addition to the already mentioned Drive Genius.
Best of luck - keep looking if you find defrag isn't what the doctor ordered on your mac.
Answer: I agree with Mark. Usually, I don't fill up a drive past 80-85%, as the slower parts of a mechanical drive begins around that point. HDs have different speeds and access time depending on the location on the disk.
Therefore using an app like iDefrag could help (remember to backup your files before!) but will likely need to be done on a regular basis to provide a continued result, and I'm wondering if the time you're gonna spend on this isn't gonna be for nothing.
I would suggest using RAID-0 or better yet RAID-5 drives setups. Bit more expansive, but speed will be much more constant over a longer period of time, but this setup also carries more risk (especially RAID-0), therefore you NEED a backup, could get expensive...
An SSD is a good solution, the only problem is the capacities. A good, fast and reliable 204 Gb SSD retails for ~500$, a 480 Gb for ~900$.
Answer: If we go little deeper we see that the HFS+ file system allocates memory not on the basis of first free space first but on the basis of largest free space first.
This technique, although reduces the chances of fragmentation but doesn't stops it totally.
Its right that fragmentation hardly matters when you are a simple home users but for professionals (Like me) a slow Mac matters a lot.
So, now I have two programs for defragmentation. One from Stellar drive defrag and another is idefrag from coriolis.
Let me try them and see if I can get some speed in my Mac.
Answer: There are many 3rd party apps available in the market which are beneficial for defragging a Mac based hard drive. Below are the top 3 player in this list (i.e. defragging a Mac hard drive): -
1.Stellar Defrag Drive
2.iDefrag
3.Drive Genius
Each of the above mentioned apps defrag the Mac hard drive and also reduce the boot time. As a results, makes it to run faster.

Mac Application to defrag my Mac drive


Export shapefile to KML for Google Earth - using QGIS

Question: I am a real beginner with QGIS.
I have shape files of my study site.
I would like to have the nice google earth background.
I would like to be able to see my files in Google earth, then I can zoom and see details at a fine scale.
from what I understood, I need to export my files as kml files.
I clicked right on the layer and clicked on "saved as", I chose a place to save and a name for the file, I chose WGS 84, and saved.
When I open the kml layer in Google earth and/or QGIS it is completely wrong.
In Google earth, appears some segments every where on the globe; in QGIS, I have on the right a vertical line.
Can anyone explain to me what goes wrong?
Comment: I'm late to the game, but .shp files can be loaded into Google Earth.
Answer: From the details you gave, I assume your shapefile is set to a wrong projection.
Easiest way to check it is installing the Openlayers plugin, and load a Google or Openstreetmap background. Project CRS must be set to EPSG:3857, and On-the-fly-projection enabled under Settings->Project Settings.
You can check the CRS your layer is set to with rightclick -> Set CRS for layer.
Also, have a look at the extent of the layer with Rightclick -> Properties in the Metadata tab
Please report the CRS and extent to investigate further.
Answer: What's your project's Coordinate Reference System set to?
Go to Project Properties, and look at the "Coordinate Reference System (CRS)" tab. You may have your project set to a different CRS than your study site's shape files. Raw traces from GPS often load up with a CRS of "WGS 84 (EPSG:4326)", so maybe your project has inherited the wrong CRS.
I find it helpful to "Enable 'on the fly' CRS transformation" in the Project Properties CRS tab. This allows QGIS to correct for files in different CRSs automatically, at the cost of some extra redraw time.
Another tool I use to check that the project is set up correctly is Barry Rowlingson's Click-Fu plugin. It's a little work to install (Go to Plugins - Fetch Python Plugins, choose the Respositories tab, and add
Name : Barry Rowlingson's Plugins
URL  : http://www.maths.lancs.ac.uk/~rowlings/Qgis/Plugins/plugins.xml

If you go back to the Plugins tab, you can install Click-Fu. It gives you a new menu that, when you choose one of the items, the location you click in your project will open in your browser in Google Maps, or OpenStreetMap. If Click-Fu gets the right location, then you know your project is set up correctly.
When the project CRS is set up, you can save shape files to KML, and you won't need to choose WGS 84 as the CRS. QGIS will do the transformation for you.
Answer: http://www.zonums.com/shp2kml.html will do it for you if you just want a simple free solution.
Google Earth pro does it automatically but at $400...
Comment: To update this answer, Google Earth Pro is now free : https://www.google.com/earth/download/gep/agree.html


Sous vide: why do cylindrical / cylinder-like and spherical / sphere-like foods cook faster than slab-like?

Question: The Douglas Baldwin's "A Practical Guide to Sous Vide Cooking" has charts for sous vide cooking times.  Unintuitive to me, cooking times are drastically shorter for spheres and cylinders than slabs.  Does anybody have an explanation?
Comment: @chaqke Asking about downvotes is rarely helpful; the voter is usually gone, and if someone with constructive advice does see it, they often don't like to reply because it looks like an invitation to argue. If I had to guess, I'd say it's because someone (a bit unreasonably) thought that your understanding or intuition was iffy, but that's just a wild guess - I'm sure there are plenty of reasons I didn't think of.
Comment: At a rough guess, the chart only *has* one dimension listed, thickness.  A sphere of that thickness has a volume, full stop.  A cylinder is a bit more variable, but two dimensions must be known, with only a little wiggleroom for length, while a slab of that same thickness could be a much larger piece, simply because length and width are completely unknown.  Maybe they assume (for some reason) the absolute size of a slab is larger, or recommend longer times because it can be?
Comment: @Megha this is an answer, not a comment. I even think it's the correct answer - due to how the words are used in cooking, a slab's thickness has to be visibly smaller than its width. If you have a piece with a square profile, a cook is more likely to approximate it to a cylinder than a slab (meat doesn't have sharp corners) and if you have a piece with a visible difference, the cook is never going to call the larger dimension "thickness". So, a slab is wider than thick.
Comment: Be careful that you are using the correct charts for your purposes.  I believe the charts you are referring to are those that illustrate heating time from 41F (5C) to 1F (.5C) below the temperature of the water bath (there is second chart that illustrates the same, but from frozen).  This is not enough to pasteurize.   So caution about who is consuming the final product is in order. Cooking times are generally longer. That said, as understand it, the charts are based on calculations of heat transfer.  To my untrained eye, spheres and cylinders transfer heat more efficiently than slabs.
Comment: @moscafj I'm using the correct charts, and beef does not have to be pasteurized to be consumed safely, as bacteria do not travel through muscle tissue very well.  The distance from edge to center is smaller for a slab than a sphere, so I don't quite understand why a slab heats up so much slower.
Comment: ..and why is this question downvoted!?
Comment: @rumtscho - I left it a comment because I wasn't sure, and in case someone had a better answer.  If you think it's actually reasonable, though, I'll write it up into a proper answer in a bit.  Thanks :)
Answer: A picture really helps here:

There's your slab, cylinder, and sphere with the same thickness.
The time to cook does depend on thickness, since that's the distance the heat has to travel from the surface to the interior. But it also depends on the ratio of surface area to volume (and thus shape): the more surface area per volume you have, the more area you have to transfer heat compared to the amount of heat you need to transfer to fully heat the meat.
So unsurprisingly, at constant thickness, a slab takes longer than a cylinder, which takes longer than a sphere.
Of course, the typical thicknesses of the various shapes are different, so it's not all that meaningful to compare things at constant thickness. A slab might be a fish filet, a steak steak, or many smaller pieces of meat packaged together in a bag - nothing all that thick, unless it's a really full bag. A cylinder might be a pork tenderloin or a decent approximation of a chicken breast - still not that thick. A sphere might be a single steak medallion, or maybe an okay approximation of a large pork shoulder - a pretty wide range.
That said, in the end we often think about things in terms of the amount of meat, i.e. the volume.  A 2 by 10 by 10 cm slab, a 5 cm diameter 10 cm long cylinder, and a 7.25 cm radius sphere all have about the same volume. According to that table, the slab needs 1.25 hours, the cylinder needs 2.75 hours, and the sphere needs 4 hours. So if you were thinking of similar quantities of meat, perhaps that matches your intuition better.
Comment: 2cm * 10cm * 10cm = 200cm^3 is 50 minutes, 10cm * π * (5cm diameter/2)^2 ~= 196 cm^3 which is 5 minutes, and π * (7.25cm)^3 * 4/3 ~= 1600cm^3....for ~200 cubic cm, r should be 3.6cm, or a 7.2 diameter sphere, which is between 8 and 13 minutes.
Comment: i think the chart skews at the "smaller values" end, so let's solve again for 6cm*10cm*10cm = 600 instead of 200.  6cm*10cm*10cm = 600cm^3 which is 4.75 hours, 600cm^3 = 10cm * 3.14 * r^2 with r = 4.37cm, diameter ~= 9cm ~= 5.25.  r^3 * π * 4/3 = 600 has r = 5.2cm, so diameter ~= 10cm, which is 4.75hours.

closer, but still a little strange :-D
Answer: So, I'm expanding my comment into an answer.
I think it's possible that the chart was assuming different volumes for the different shapes, since only one dimension (thickness, which is usually the thinnest dimension) was listed on the chart.
So, for example, given a piece with a centimeter's thickness, the resulting sphere is a little nugget of one centimeter in all directions, with no wiggle-room, since spheres are symmetrical.  A cylinder of the same thickness has its diameter defined, since width and thickness are the same in a cylinder, even if its length can be more variable - so a cylinder one centimeter thick, can easily be three centimeters long, and thus starts with about three times the volume of it's spherical "counterpart".
And then there's the slab.  With only the thickness given, it can be considerably larger in both length and width.  Looking at a one-centimeter thickness, we can start at three centimeters wide to match our previous three long, and three wide to make a flat slab instead of a strip, for nine times the volume of a one-centimeter sphere and three times the volume of a one-by-three centimeter cylinder.
As rumstscho's comment mentions, the difference must be rather visible for the shape to be considered a cylinder rather than a sphere, or actually a strip vs a cube (give or take irregularities and/or rounded edges), so it must have a longer length to qualify.  Same for a slab rather than a cylinder - it must be visibly larger in two dimensions, or else it will look more like a strip or chunk (square-ish or spherical).
It is rather intuitive that a larger piece, with more volume and more mass, will take longer to cook, longer for the temperature to equalize form the edges in.  Of course, that makes the "intuitive" problem the chart setup, which is comparing pieces of rather different sizes based on thickness alone - it might make a bit of sense for the rate of diffusion to be based on the thinnest dimension, but the results are, as you said, counter-intuitive since I didn't see anything mentioning that assumption.  The time should be the same if the other variables like absolute size didn't matter, but clearly they have to be taken into account somehow.  It might have made more sense to compare profiles for pieces of the same volume, or make a chart for each shape, or just mention the assumptions being made or something.
For the same volume, the same mass, I would expect a thin flat slab to heat up much faster, and a sphere or cube to heat slower, because of the ratio of surface area to volume.  But once we're talking different amounts of mass in each shape, yes, I would expect the same volume of food to cook faster as diced small cubes, as opposed to cut into longer strips or left as fewer, wider planks, simply because the pieces are smaller and there are more cuts, therefore more surface area.
Comment: yep, i agree that the chart goes by one arbitrary measurement instead of by meat volume, which would make the chart more intuitive, and that these terms implicitly add volume to the meat.  you/me/cascabel are in agreement on that, and the people who think spheres have _more_ surface area are barking up the wrong tree with regards to physics (hence the original confused intuition).  no ding on their attempted helpfulness though!
Answer: Physicist here.  There's a very simple explanation.
Heat (as in energy) can only transfer through the surface of the food.  Spherical objects have the same distance to the center of the sphere from all sides, but in a slab, the distance to the center is much shorter top and bottom than it is from the side.  (For a 2" thick slab, it's 1" to the center from the top but might be 4" to the center from the side.)  Because of this, all of the energy required to cook the center effectively comes from the top and bottom.
 Very loosely, you are eliminating about half the surface area through which energy can flow, so it takes about twice as much time to reach the same temperature.
Comment: still feels unintuitive, because i thought spheres had the worst (largest) ratio of volume to surface area...thinner things like slabs should have more surface area to volume, if we're keeping volume constant.  clearly i'm wrong if the chart is right, so i'm guessing it's just that we'd call a smaller volume (smaller piece) a spheres, and only humanly use the word slab for a larger volume piece of meat.
Comment: just reviewed the other comments and re-remembered.  i'm fairly certain that the answer is that the words "slab" and "cylinder" imply larger quantities of meat.  keeping volume consistent, spheres should have the highest volume to surface area ratio, and cook the slowest - it's just that a cylinder of the same _VOLUME_ of meat would have a smaller thickness, so comparing "equal" thicknesses is inherently comparing different quantities of meat (so their cook times should indeed be far apart).  V = 4π(r^3)/3 vs π(r^2)h vs LxWxH...but thanks for trying!  this is definitely unintuitive :)
Answer: As someone who took a course (years ago) specifically on heat transfer, I'm pretty sure Baldwin just used the standard modeling equations that assume an infinite slab and an infinite cylinder.  That is, the model assumes that a horizontal slab only absorbs heat through the top and bottom, a cylinder only absorbs heat through its curved sides (not any "top" or "bottom"), and a sphere absorbs heat through all directions.
Or, to put it another way, what these "shapes" really mean is how many dimensions one assumes heat can be coming from.  In the slab case, heat can only travel in one dimension through the slab.  In the cylinder case, it travels in two dimensions.  And in the spherical case, it travels in three dimensions, which is the reason for the shorter cooking times.
To those answers and comments speculating that Baldwin is assuming a larger volume for slabs and cylinders, I suppose that's correct, as the equations in general assume an infinite volume.  (And the reason why the equations make these assumptions is because the math gets really hard, really fast if you want to model more complex shapes.)  Obviously, real food doesn't have infinite volumes, so Baldwin's calculations should only be taken as an approximation.
There are methods using the equations to approximate other shapes, which Baldwin mentions briefly.  Effectively, what one does is assume a non-integer number of dimensions for heat travel.  For example, an infinite square prism (like a cylinder, only with square sides) would have more than the single dimension of heat travel assumed by the slab, but less than the equal travel from all directions in two dimensions assumed by the cylinder (because of the corners of the square, which means heat will take longer to travel toward the center).  So, one can plug in "1.7 dimensions" and get something that's closer to a cylinder than a slab and get a number that's a reasonable approximation to how other shapes behave.


iPhone 4/4S Rattle

Question: I've noticed that when I tap near the top of the back of my iPhone 4S, there is a audible rattling noise.  I've tried this on someone else's iPhone 4, and it is the same.  It seems to be coming from the area around the rear-facing camera lens and flash.  Does anyone know the part responsible for this, and it it normal or should I investigate having it repaired?
Answer: I noticed the exact same thing when I got my iPhone. At first it concerned me but then I noticed that the other 2 or 3 brand new iPhone 4S's that I tried had the same sound. It also happens on iPhone 4's (the one's that I tried). I'm guessing it is the vibrator (this post has more info on the problem).
While I don't know that for a fact, because everyone else's (that I've tried) iPhones that I've tapped like that have the same sound, you are probably OK. Just to be safe, you couldn't go wrong with scheduling a Genius Bar appointment and seeing what they think. It could be something different then what I've experienced.
Answer: It's actually the sleep/wake button that rattles. It's pretty normal, and pretty easy to get used to. You can go to the Genius Bar if you like, but they may write it off as normal behavior and not replace your phone for you. Even if they do, there is no guarantee that the new one won't do it too. If it does, they are not allowed to continue switching out phones for you until you're happy (it's specifically stated in internal Apple policy guides).
My recommendation is to deal with it and maybe think of it as a pleasant melody.
Comment: Yep, Matt's bang on. On my iPhone 4, it was barely audible. On my 4S, it is quite loud. I took it in and they replaced it, but it really isn't any stiffer (though a bit better). The Genius on hand said it was a "one time" cosmetic replacement, though they tend to say such things sometimes to make you feel special ;)

iPhone 4/4S Rattle


How much fork to tyre clearance do dedicated cyclo cross bikes need?

Question: I wish to take part in my first cyclo cross race but would like to avoid buying anything (other than tyres) until I have tried it. I currently ride a Kona Honky Tonk which I believe has enough clearance to have 32c tyres without fenders. Will this be enough clearance for all the mud or will it gum up the entire area and create friction and stop me mid race? Also It has dual pivot calliper brakes.
Answer: It would be very tight, looking at the bike I think 32c with knobbies might not even fit. It also has to do with the height of the tire. By adding the knobbies I doubt you will find a CX tire that will fit under the brakes.
There are not many options for 30c or smaller CX tires. If you can find some tires that fit (will be tight) it will clump mud, but might not lock your wheels up. It depends on the mud, not all mud is the same, some sloppy/wet mud will not clump.
But extra clearance doesn't mean everything rolls smooth. The mud in a race two weeks ago on my 29er was so thick that both front a rear wheels locked up.
All that being said, you can find a CX race that has less mud. Great fun and highly recommended. Another option is to race on a mountain bike to see how you like CX racing.


Proper way to construct MySQL queries in python?

Question: After starting with python last week after coming from php I am wondering what is the best way to build a MySQL query.
I am using Python's MySQLdb module.
After doing some research it seems the best way is something similar to the following code below:
def updateEmployee(employee):
  try:
      cursor = db.cursor()
      cursor.execute("""
          UPDATE `employee2`
          SET `employeeID`=%s, `parentNameN`=%s, `firstName`=%s, `lastName`=%s,     `title`=%s, `room`=%s, `locCode`=%s, `posOrg`=%s
          WHERE  `employee2`.`nameN`=%s
      """, (employee["employeeID"], employee["parentNameN"], employee["firstName"],     employee["lastName"], employee["title"], employee["room"], employee["locCode"], employee["posOrg"], employee["nameN"]))
      db.commit()
      print employee["nameN"]+" updated"
  except MySQLdb.Error, e:
      print "Error %d: %s" % (e.args[0], e.args[1])
      sys.exit(1)

This is all great except, when this errors I get something such as "Error 1064: You have an error in your SQL syntax:..." which is nice, it says my query was syntactically incorrect.
So I got that part, but how can I view the query in question?  Is there a way I can construct this query outside of the cursor.execute so that in situations where I get generic error messages I can at least do a "print query"?
Answer: You don't need backquotes in your query.  Mistake is here `posOrg`:%s
SET `employeeID`=%s, `parentNameN`=%s, `firstName`=%s, `lastName`=%s,
 `title`=%s, `room`=%s, `locCode`=%s, **`posOrg`:%s**

Comment: I do not understand your answer?
Comment: Replace posOrg:%s with posOrg=%s
Comment: Ah I think its time to take a break from coding.  Any suggestions on the original question to general querying in python?


Is there any way out so that a video available online cannot be downloaded?

Question: Is there any way out so that a video available online cannot be downloaded ? I have checked almost every way out and found that everything can be spoofed. So does anyone knows anything else that cannot be spoofed ?
Answer: You need to understand that in order for the human user to view the content, the browser (or some other software) need to download it.  And when the content has been downloaded to the user's computer, you no longer control the access to it.
So-called "streaming" is just a download-mode where the standard viewer is programmed to automatically delete the content after it has been viewed by the human.  However, this can be circumvented by either using a non-standard viewer (i.e. one that skips the deletion step), or by having another piece of software running that grabs the content from the frame buffer when it being viewed - and saves it permanently.
If it can be viewed, it can be captured.
Comment: Another characteristic of streaming is that the content typically begins to be viewed *before* it is completely downloaded. (Doesn't change the answer here, but you might want to add that to present a clearer picture of streaming.)
Answer: If you're looking for absolute security, then no. Everything that can be seen can be downloaded. You can just make it harder. Screengrabbing will always work.
Answer: Not if someone really wants the content, no.
But to defeat casual users, you can try the following:

host your video on amazon s3 + cloudfront
use signed urls so the url can only be requested from a certain ip for a certain amount of time
keep the signed url generating page (say php) behind a login, and only let them login from a certain number of ip addresses per month

if they have stream capturing software, then you are out of luck, but they can't share the login with too many people, and they can't share the video url with anyone.
Also see http://en.wikipedia.org/wiki/Protected_Streaming


How is a second radio managed when operating SO2R (Single Operator Two Radios)?

Question: I am relatively new to contesting, and I have heard of a category called SO2R (Single Operator, Two Radios).  Are they really talking about 2 radios, or just 2 VFOs in one radio?  Running one radio seems to be a full time job, especially with the logging involved.  How is the second radio used?  What are the advantages over a single radio?
Answer: Generally SO2R means one person ("Single Operator") with two separate transceivers attached to two separate antennas ("Two Radios"). The operator doesn't actively transmit and receive on both at the same time, as you say it's a full time job with just one radio.
The second radio (that is, which ever radio is not currently being transmitted on), is typically used to listen on a different band while they are transmitting with the first radio. The only real advantage of this in a contest sense is to score more points. The more people you can hear calling the more you can respond to, and more contacts equals more points.
Also, assuming you aren't actively transmitting, you will be receiving on two separate bands, which increases your chances of hearing someone calling.
Answer: I believe you can also call CQ on one radio while search and pouncing on the other. I imagine this takes some level of skill to use effectively.


my rabbit absolutely will not eat hay and very little pellets

Question: I have a year old male rabbit that will not eat hay of any kind and barely eats any pellets. He has been this way since we brought him home. I have tried all kinds of hay and hay cubes. I've bought plain pellets and pellets with other stuff mixed in. I finally started feeding him a limited amount of fresh vegetables and a little fruit which he loves. He also loves fresh picked grass. Any suggestions on what to do with this lucky guy?
Answer: First, worth checking My rabbit will not eat his hay! How can I motivate, or even begin adding hay into his diet? for some good information on some hay types to try. He may simply not like the brand/variety you're supplying him. Fresh is better and he needs to have it available.
On the topic of pellets, well, when I had rabbits, the pellets were there as a backup in case we were late in feeding them. A good mix of fresh veggies is much better for your bun, pellets are more like junk food and I would minimize them. The House Rabbit Society has more detail on the topic as well as lots of food suggestions, especially which veggies are appropriate and which to avoid completely (there are a few).
Answer: To piggy back off the previous answer, I agree trying a different higher quality  hay will likely do the trick. A rabbit's digestive system is designed for a high fiber diet--not one high in fat, protein or sugar.  I recommend farm fresh Timothy Hay (for rabbits and all small pets) and here's why.
Quick Story:  Knowing rabbits needed high quality hay, I became sold on timothy hay when mom had gotten a guinea pig named Lizzy that would not eat her timothy hay from the stores. I was a little upset at my mom when I found out about this, because we happened to live in Ellensburg Washington, which is literally the timothy hay capital of the world! I knew I could get Lizzy way better hay than what she was getting from the stores. And sure enough, when I did, she gobbled it down and asked for more.
Timothy hay in the stores is usually at least 1 year old, and often times 2 years old or more! That's because this hay has to go through a much longer supply chain. Not to mention the loss of moisture from plastic packaging. Due to its freshness and natural sweetness (which is attractive to rabbits), trying a farm fresh hay may work for your rabbit as it did our guinea pig.
Finally, besides digestive health, the other reason rabbits should eat hay is for dental health. Eating hay aids in the natural renewal process of rabbit teeth.
There are so many factors to consider when considering your rabbit's food and nutrition, but hay is at the very core if their diets.  Here is a handy rabbit nutrition guide.
Comment: Your current user name suggests that you may be editing on behalf of the company who's links are in your answer.  If that is the case please add a notice in the answer, indicating your relationship with the company.


Visual Flow - Unable to pass multiple selected values from one screen to next screen

Question: I want to create a visual flow wherein there will be two screens. On first screen I want to select few fields(only name of fields will display in multiselect picklist) from a list of lets say 20 fields, now on the next screen I want to show those selected fields with respective input text boxes and then user will fill this form and record gets saved. How can I achieve this as I am unable to pass multiple selected values from one screen to next screen.
Answer: At the moment of writing, this is not possible. The only thing that might be possible is creating a collection of variables, looping over these variables and show a screen for each instance, representing a choice from the multiselect picklist. Than you can put input text boxes on each screen. This means that when a user chooses 10 options, he will see 10 screens, which is not very neat.
I would build a custom page for this. It is probably faster and might even be better maintainable.


What affordable beachfront hotels in or near San Diego should I consider?

Question: I'm looking for a beachfront hotel in or near San Diego for my family (on the theory that the water there is warmer than say Los Angeles or certainly Pizmo Beach).  I'm hoping to find a hotel near a beach suitable for beginner's surfing.  And by "affordable", I'm hoping for $200/night or less.  (Though I'll spend more if I'm convinced it's worthwhile or necessary.)
Comment: Temperatures are pretty uniform in southern California unless it's a protected bay, and even those are only a few degrees warmer. [US NODC Coastal Water Temperature Guide: Pacific Coast: South](http://www.nodc.noaa.gov/dsdt/cwtg/spac.html)
Answer: Tower 23 Hotel
723 Felspar Street, Pacific Beach, CA 92109 San Diego
Follow this link :
http://goo.gl/xZdT2
The price is around 199 USD/night(from booking.com) and the booking.com review score is 8.5. It also states that "Guests at Tower 23 are surrounded by a large variety of recreational activities. Hiking trails, fishing, golf, surfing and whale watching are only minutes from the front doors"
from what I searched in Google, it seems that you can surf in Mission Bay which is very near to the hotel.
if you click the review section, a couple from Germany also stated "...direct view from the balconary to the sea; a lot of surfers in front of the hotel..."
Answer: I've been to San Diego a couple of times and both times stayed in vacation rentals instead of hotels. This worked great for our family because it meant we had our own garden and felt very settled while we were there. We stayed somewhat north of the city in Del Mar and Encinitas. Both these areas were great. I'm not a surfer, but there's always lots of people surfing around those parts, so I don't think you'd have trouble getting some surfing in while there. While a lot of the houses will be more expensive than $200/night, I think you'll still find plenty of suitable options at that pricepoint.
Homeaway, VRBO or AirBnB all have a lot to choose from.
Comment: Ah, just noticed the date on this. Sorry for answering such an old topic. I guess I clicked through from the sidebar.
Comment: it's good to answer old questions! Remember that your answer could be very useful for the OP, but also for someone else who is facing the same problem now (or later)
Comment: Yeah, I guess someone might get something out of it.


Monthly automatic email to one person

Question: I have Gmail.  I need the same email content sent to the same person, at the first of each month.  Is there a way to set that up to happen monthly without having to think about it or do any action?
Comment: This is not something you can do natively in Gmail. You'll need a third-party service.
Answer: I recommend Boomerang for Gmail.
You could also connect your Gmail to an Outlook account and use Windows' built-in Task Scheduler to send an email through Outlook (from your Gmail account).
Answer: You could use If This Then That.
This recipe will have an email sent on a specific day of the month. You also define the recipient address, the subject, the body of the email message and you can even provide an URL to attach a file.

Monthly automatic email to one person


"How long have you been working?" vs. "How long you have been working?"

Question: I think "How long have you been working?" and "How long you have been working?" are both questions, so, could you tell me what is the difference between them?
Comment: The second is not a properly formed question, alternative might be "You have been working *for* how long?"
Answer:
How long have you been working?
*How long you have been working?

The former is grammatical; it's a direct or normal question.
The latter has not been formed properly.  If you omit the question mark, you can form an indirect question in indirect (reported) speech as follows:

He asked me how long I had been working.

To be more polite and formal, you can also form an indirect question in the following way:

Could you tell me how long you have been working?
Comment: "He asked me how long I have been working": this is wrong. You have so say "He asked me how long I _had_ been working."
Answer: They are not both questions.
"Have you" is part of a question:

Have you been working? How long?

"You have" is part of a statement:

You have been working. I know how long.

In a question without a question-word with "be," the subject and verb order change position to indicate that it is a question.
So, "How long you have been working?" is an error. A correct statement using that word order: "I'm amazed by how long you have been working!"
Answer: I don't think either of the existing answers have covered this case. But the second form, you have could be used to express surprise at how long someone has been working.
A commonly told childrens story, Red Riding Hood, is usually told with some variation of this refrain:

My, what big ears you have!
What big eyes you have!
What big teeth you have!

It's a little archaic, now, and rarely used in common language, but this may be the intention of your initial sentence.
I just thought I'd try to help, because that's the kind of guy I am. ;)
Comment: Maybe expand your answer to clarify the correct archaic statement you are implying is possible based on OP language. I think you are suggesting: "My, how long you have been working!"


If Muslim university student sins in a non-Muslim country (by e.g. drinking alcohol), will his repentance be accepted?

Question: If a Muslim university student who was born in a non Muslim country has been in a company with non-Muslims, he has sinned out of ignorance (by e.g. drinking alcohol) with them, then regrets what he has done, repents and gets away from the company will his repentance be accepted? Are these non-Muslims going to be held as witnesses to the sins If a Muslim repents?
Comment: What makes you think your repentance will not be accepted?
Comment: A college kid goes to a party. It's not the crime of the century, is it? Make tawbah.
Answer: What prevent him from repentance?
Only we have to fulfill the conditions to have correct repentance:

Regretting what we did of sins
Having stronge will to avoid getting back to sins
And of course, taking off from the sins

Even if we did sins again, we should repent again.
We should be ready for going to the last day. Every day of our life is a chance for repentance.
Very important to note the strong effect of company and to keep goo
Comment: Salam and welcome to Islam SE the Q&A site about Islam. To learn more about our site and model I recommend you to take our [tour] and check our [help]. Your answer could be more helpful if you added some evidences to support your claims (see [answer]).
Answer: Asalamualaikum.
No matter how much sins you do or how many of them. Repentance is always accepted. Its Allah's greatness that He accepts repentance. The person should repent by heart and having intention of not repeating the thing again.
Comment: Welcome to Islam SE. Answers should be elaborate and focused on addressing the question. Claims should be supported by evidence. Please visit our [tour] in the [help], and refer to [answer].
Answer: Firstly, your answer is in the first aya of the first surah :
Bismillahi Ar Rahman Ar Raheem
In the name Allah, the most beneficent, the most merciful
Allah's mercy is infinite.  If you are sincere in your tawba (repentance), InshAllah you will be forgiven.
Second, sins against yourself are more easily forgiven than sins against others.  One of the hadiths states "do not leave the dunya with the haq (rights) of others".  When you consume intoxicating drinks you are inflicting 'Zulm' (tyranny, harm) on your own body with these poisons.  Several ayas in the Quran mention that your own organs or skins will testify against you on the day of judgement.  So, the non-muslims who you shared intoxicating drinks with don't have to testify against you since your own organs will be doing the testimony.  Allah entrusted you with the stewardship of your body.  It does not belong to you but to Allah.
Also, time that your mind is in a drunk or senseless state is time that is not devoted to worshiping Allah or in taqwa.  When you are not practicing taqwa, your conduct can drift towards evil conduct to others.  Sins against others are less easily forgivable. If you have sinned against others while drunk, and they have not forgiven you before your death; then they will have their day in court on yaum i deen.  As the 'Hakeem' (most fair and supreme judge), Allah has to be fair to the victims of your sin, and mercy becomes more complicated.  So it is not so much the zulm against yourself, but rather any wrong or bad speech you have committed against others in the intoxicated mind state that you need to be more concerned about.  If you have wronged others, make sure you have their forgiveness before you die.
I hope the above addressed the core of your question.  I would like to elaborate a bit more on the value of and purpose of tawba.
If Allah sbwtl had so willed he could have created us as robotic droids who never make mistakes and worship him perfectly.  This would have been easy for Allah to do.  Instead, the reality is that Allah created mankind out of 'sijeel' dark mud or potter's clay.  A heart and soul that is dark is one that is not innocent and has much potential for evil conduct.
Quran 95.5: Then do We abase him (to be) the lowest of the low,-
A heart and soul that is like clay symbolizes that it is not a fixed form but rather one that can be molded into better more pious forms and indeed potentially the best of forms.
Quran 95.4: We have indeed created man in the best of forms,
We mold our heart and soul into better forms with righteous deeds, practicing worship (sala), charity (zekat), fasting (sawm), taqwa, and tawba.
When we realize the mistakes we make, and then sincerely make tawba to Allah, we mold our sijeel heart and soul to a better form that is closer to Allah.  If we never made the mistake we would have never made the tawba and not had the learning experience that gave us the increased understanding to come closer to Allah (Yakeen).
Quran 95.6: Except such as believe and do righteous deeds: For they shall have a reward unfailing.


Is "pitch diameter" the same as the distance between the centers?

Question: I am designing gears in FreeCad, and printing then on a FlashForge Finder. I want to know if the pitch diameter is the same as the distance between the centers of the two gears. Both gears are external spur gears.
Comment: It's not unclear, but doubtful if it's really on topic. Easily answered with a web search.
Comment: Hi, and welcome to 3D Printing SE! I find your question is a bit unclear: what are we discussing here? Is there a "pitch diameter" in FreeCad, on your FlashForge Finder, in some theoretical mathematical model of gears, or some CAD model that you are currently designing? When writing your question, plese try to be as *specific* as possible. If the question is not obvious, you might want to include some sketch, or give and example to make it easier for other users to understand. I have put your question *on hold* for now, so that you may do your edits.
Comment: @Greenonline, you seem know this topic. Do you think we should reopen it, or perhaps migrate it to Mechanical Engineering SE?
Comment: Alright, thanks @Greenonline. :) I will migrate it to the ME site then, since it is not directly relevant to 3D printing. Perhaps you could post your answer there. ;)
Answer: Pitch diameter is the diameter of the pitch circle described by the mid point of the length of the teeth around the gear, as shown in this diagram:

The pitch circle defines the point where the teeth of two gears meet:

Let's say you have two gears, each with a respective pitch circle diameter of $d_1$ and $d_2$. The distance between the two gear centers, $C$, is given by,
$$C = \frac{d_1 + d_2} { 2 }$$
If the gears are identical ($d_1 = d_2$), then the pitch diameter is, indeed, the same as the distance between the two gear centers, $C$. Otherwise, is it not.
Another method of calculating the gear center distance is,
$$C = \frac{N_1 + N_2}{2P_d}$$
Where $P_d$ is the diametrical pitch, and $N_1$ and $N_2$ are the number of teeth of the respective gears. From Gear design equations and formula

You may find the following useful - from Wikipedia - Standard Pitch Diameter:

The standard reference pitch diameter is the diameter of the standard pitch circle. In spur and helical gears, unless otherwise specified, the standard pitch diameter is related to the number of teeth and the standard transverse pitch. The diameter can be roughly estimated by taking the average of the diameter measuring the tips of the gear teeth and the base of the gear teeth.
The pitch diameter is useful in determining the spacing between gear centers because proper spacing of gears implies tangent pitch circles. The pitch diameters of two gears may be used to calculate the gear ratio in the same way the number of teeth is used.
$$d = \frac{N}{ P_d } = \frac {pN}{\pi}$$
Where $N$ is the total number of teeth, $p$ is the circular pitch, and $P_d$ is the diametrical pitch.
Answer: As indeed answered by Greenonline, the centre distance is the average of the pitch diameters of the two meshing gears, but this is only strictly true when the gears are operating at standard centre distances, i.e. where the pitch circles are tangent to one another. There are indeed cases where two gears can be operating at non-standard centre distances, and therefore the standard pitch circles are no longer tangent to one another.
Sometimes non-standard centre distances are accidental and occur due to difficulty in exactly aligning two gears to have a standard centre distance. Other times it may be a deliberate part of the design. For example, slightly increasing the centre distance above the standard value will implement some backlash (as shown below) which helps to prevent any jamming from occurring.

Here are two gears operating at standard centre distance:

And operating at non-standard centre distance:

Most gears in industry have teeth that are involute (the notable exception to this is in the clockmaking industry, where teeth are frequently cycloidal instead), and the advantage of involute teeth is that gears can still operate smoothly at non-standard centre distances.
When dealing with non-standard centre distances, we have to be careful by what is meant by pitch circle and pitch diameter. The diameter of the pitch circle, the pitch diameter, is a dimension that belongs to a single gear on its own, regardless of how and with what it mesh. However, the pitch circles for a pair of meshing gears also represent the diameters of two equivalent disks that are rolling without slip; this means the pitch circles should be tangent. For operation at non-standard centre distance, there appears to be a contradiction in the definition of a pitch circle: therefore, the two following terms should be observed:
Standard pitch diameter: this is a dimension on a gear that is independent of how or with what it meshes, and defined for any two meshing gears as follows:
$$d_1 = N_1m = \frac{N_1}{P_D}$$
$$d_2 = N_2m = \frac{N_2}{P_D}$$
Where $N$ is the number of teeth, $m$ is the module (a measure of tooth size in millimetres), $P_D$ is the diametral pitch (a measure of tooth fineness in teeth per inches) and the subscripts 1 and 2 indicate which gear the variable refers to.
This is the dimension that is provided when buying gears "off the shelf". Taking the average of these diameters for both gears will give you the standard centre distance, which may or may not be equal to the actual centre distance.
$$d_1 = \frac{2C}{\frac{N_1}{N_2}+1}$$
$$d_2 = \frac{2C}{\frac{N_2}{N_1}+1}$$
$$C = \frac{d_1+d_2}{2}$$
Where $C$ is the standard operating distance.
Operating Pitch Diameter: this is a dimension that only exists when two gears are meshing together, and it represents the diameters of the equivalent rolling disks. The operating pitch circles are tangent to one another, and taking the average of these will indeed give you the actual centre distance, i.e. operating centre distance. If the centre distance is larger than standard, then the operating pitch circles will be larger than the standard pitch circles. The operating pitch diameters are defined as follows:
$$d'_1 = \frac{2C'}{\frac{N_1}{N_2}+1}$$
$$d'_2 = \frac{2C'}{\frac{N_2}{N_1}+1}$$
And so...
$$C' = \frac{d'_1+d'_2}{2}$$
Where $d'$ is the operating pitch diameter, and $C'$ is the (actual) operating centre distance.

A final point worth noting: there are limits to how much you can vary the centre distance from standard: there is a minimum centre distance below which the gear teeth will jam with one another, and there is a maximum above which the teeth will no longer reach and make contact with each other:
Comment: +1 - A very interesting and most detailed explanation. I had avoided dealing with the backlash, and had gone as far as editing one of my images to remove the backlash reference/detail.
Comment: +1 Good stuff and more.  Also to note again, depending on the tip relief and other design adjustments the pitch circle will not pass through the centre of the tooth as such.  At first glance it is always going to look close but by design it may be placed above or below the centre of the tooth.
Comment: +1 great explanation. I would also add the fact the the transmission ratio is always constant, no matter how the center distance changes. It is not so obvious and actually quite amazing.
Answer: Yes they should, in theory, and for most practical purposes  be the same.
The pitch circle diameter is the effective radius of a gear in terms of torque, although for some tooth profiles this may be a mean value.
In practice gear design often uses the module system which defines gear ratios by number of teeth for a given tooth profile and ensures that you always have an integer number of teeth and eliminates pi, making calculations more convenient.


Tails 1.3.2 takes an inordinately long time to start on Alienware 14.

Question: I have verified the Download.  Same ISO of Tails 1.3.2 starts far faster on a 2009 Mac Book Pro.  A previous version of Tails also took much longer to boot, but eventually it would start, and probably would this time.   I have the Ethernet cable from the router Plugged in, worked well for the Mac and in the Windows of the Alienware.  I am starting in Tails Option Safe mode.  While yes, it adds more time, I turned off the fast boot in the BIOS, thinking that while it would do a memory check, Tails is not the Windows 8.1 PRO.   I turned off the secure boot and UEFI, and set it to use Legacy Boot.  After 15 minutes booting on Alienware,  I get past where Tails asks its long list, do i want to log in, Do I want to use a bridge.   I choose none of those. I would guess it takes over thirty minutes to boot Tails in a far faster Alienware than Mac Book Pro.  Absurdly long.   I am guessing some Alienware hardware is giving Tails some difficulty.   How can I get a txt list of what is happening during the boot, and see what it hardware it does not like.  Or what might I try?
Comment: Thanks for Answering.   The drive is fairly new, and seems to work pretty well with playing movies.   I suspect that I should look at a file which has all the things which are occurring at boot.  I feel that booting with a USB is essentially not very secure.  However, I might give it an experiment..
Comment: CTRL+ALT+F1 will show the Verbose boot. CTRL+ALT+F7 will get you back to the "normal" boot screen. Failsafe mode shows way more info with F1 than normal mode.
Answer: It may be related to your optical drive. If you are booting from a DVD then that might be the limiting factor. You may want to try using a USB stick, which should be way faster than a spinning disk.
A specific reason could be that the laser inside your Mac Book is better/less dusty or that the CD you used has better compatibility with it.


can multiple encryption of data with multiple keys increase the security?

Question: I mean: does encrypting data multiple times have an effect on diffusion and confusion?
Does it increase security, or does it have no effect?
Is it useless?
Does it make it harder to break the secret, or not?
Comment: ROT13 should never be used an even number of times.
Answer: Yes, multiple layers of encryption using different algorithms and different keys make the encryption as hard as the hardest in the chain.
IIRC this was adressed in Bruce Schneier's book Applied Cryptography (2nd edition).
But the important part is to use different algorithms, or at least different keys. Algorithms that use "round keys" are often optimized for a number of rounds. Using the same key will not necessarily make the message harder to break, and can theoretically make it easier.
A nice example is Triple-DES. Encrypting a message, then encrypting it again with a different key was vulnerable to meet-in-the-middle attack and effectively added only 1 bit of key space. Instead, it was found that one had to encrypt a message, then use the decryption algorithm but with a different key, then encrypt it again.
Even with 3 independent 56-bit keys, the effective key size is 112 bits as it is vulnerable to a meet-in-the-middle attack (source: Wikipedia).
So the strongest way is to use different keys and different algorithms.
Comment: Citation (p. 367): "Using a chosen-plaintext attack, a cascade of ciphers is at least as hard to break as any of its component ciphers." and "Only if the algorithms commute, as they do in the case of cascaded stream ciphers (or block ciphers in OFB [+CTR mode, which is considered an OFB variant in this book, added by me] mode), is the cascade at least as strong as the strongest algorithm"
Comment: yes there is a chapter about multi-encryption in Applied Cryptography. Schneiers states there that double encryption doesn't do a lot of good (+1 bit due to meet-in-the-middle). He also states that EDE is quite a nice choice, as it doubles the margin. (both for multiple applications of a single cipher)
Comment: The meet in the middle attack works on Encrypt-Decrypt as well; you need three layers to get twice as much security.
Comment: I thought the choice of decryption for the second step in 3DES was for backward compatibility with regular DES - set all 3 keys to the same value, and the result is the same as if you just used DES. Encrypting 3 times would have been equally secure.
Comment: Also, wouldn't the same meet-in-the-middle attack against 2DES work against a scheme that used two different algorithms? The importance of different keys is obvious - using the same key for each encryption doesn't increase the amount of keyspace to search - but the use of different algorithms doesn't seem to be important.


Python implementations of Gillespie's direct method

Question: I'm looking for a decent implementation of Gillespie's Direct Method in Python, as if I code the algorithm myself I'm nigh positive I'll do it inefficiently.
Anyone have a favorite?
Answer: I would warmly recommend to use StochKit, which is really extremely reliable and efficient. It implements the Gillespie's direct method as well as its most popular optimized variants. Furthermore, it has a built-in mechanism for selecting the appropriate simulation scheme depending on your network.
However, it is written in C++. If you really need to integrate it with a Python, that shouldn't be a problem. I use it extensively in MATLAB scripts (basically, MATLAB writes a descriptor of the simulation, calls StochKit, and finally performs the data analysis).  I'm sure you could do pretty much the same thing with NumPy or SciPy.
Comment: Looks like there is a Python2/3 wrapper for StochPy now, and it seems to work very well. [Here's the github](https://github.com/SystemsBioinformatics/stochpy)
Answer: (Disclaimer: I haven't used any of the packages or code below.)
Finding any implementation of Gillespie's method in Python was a bit of a challenge; the most fruitful search terms seemed to be "tau leap" or "kinetic Monte Carlo." This blog post implements Gillespie's algorithm, though it's not clear that it's efficient. One of the commenters mentions some other Gillespie/SSA algorithm implementations in Python that solve problems out of a textbook; the relevant problems are 6.3 through 6.6 on this website.
The most promising implementations in Python that I found were StochPy and Python language bindings to COPASI. I also found what looked like promising C++ codes in SPPARKS, STOCKS, and StochKit; they're not Python, but maybe you can wrap around one of them in Python if it looks particularly promising to you.
Answer: As part of the lab the developed and maintains StochKit.  I am happy to hear that it is highly recommended in the previous answers.  However, I wanted to update everyone.  There already is a python wrapper for StochKit: GillesPy.
I would also recommend you checkout StochSS, This is an fully functional modeling and simulation IDE that uses StochKit and as one of it's simulations engines.  It also includes spatial simulation with the python package PyURDME.  Model building, and 3D visualization tools (plus cloud computing integration).
Answer: As you may already know if you're asking this question, Gillespie's method is often used in computational systems biology.  There are a number of software system that provide implementations; you may want to browse the SBML Software Guide to find some of them (specifically, the ones that are known to support SBML, something that I realize may not be relevant to your needs). However, Geoff Oxberry is correct that Python-based implementations of Gillespie's algorithms seem to be uncommon compared to C++ and Java implementations.  In addition to StochPy, I'm aware of the following Python-based packages (in alphabetical order):

ByoDyn
SloppyCell
STEPS

If, in your application, you can use software that's coded in something other than Python but can be wrapped with a Python interface, then there is

Cain — the core is C++, but it includes a Python-based interface
COPASI language bindings
several more options as mentioned by Geoff Oxberry in his reply on this page

Finally, if you don't need your simulation to be run locally and can instead use web services, then there are the following options:

BASIS
(the simulation service is currently off-line, but will return) SBW
ByoDyn's online services (see link above)

These lists are still incomplete, but hopefully they will help.
Answer: I wrote a small Python package called OOGillespie whose main feature is that it is rather flexible and embraces object-oriented programming.
Efficiency was not the main priority when writing OOGillespie, but I tried to keep things fast, where it did not lead to a major slowdown.
OOGillespie will probably not be able to compete with other implementations for standard tasks, but it may be the only implementation that can handle some non-standard ones.
If your bottleneck is computing transition rates from large matrices, OOGillespie may be competitive again by allowing you to use NumPy matrix operations for this purpose.
Finally, depending on how experienced you are with classes, OOGillespie may cut down your programming time.
At the end of the day, I do not think that you can simply rank Gillespie implementations without knowing the specific application as a major point is what kind of events you have and how you can calculate tehm.
Answer: I have made my own simple implementation and created short tutorial, hope it will be helpfull:
i just converted the gillespie's algorithm into python code:
1.Define total simulation time T and set current time t=0;
2.Initialize the state of the system x – choose randomly or set zero state;
3.Find the sum Q of all the possible transition rates from the current state x;
4.Simulate the time Δt until the next transition by drawing from an exponential distribution with parameter Q;
5.Generate a random number r from a uniform distribution;
6.Set the next state n as follows:
If 0 < r < q(x,0)/Q, choose transition 0; if q(x,0)/Q < r < (q(x,0) + q(x,1))/Q choose transition 1, and so on;
7.Update the current time: t=Δt+t;
8.Repeat 3-7 until t≤T.
The source code in python:
https://github.com/mamedshahmaliyev/adhoctuts/blob/master/python/math/mc_gillespie.py
additionally, the result of simulation is compared with the exact result using mean squared error (MSE).
https://adhoctuts.com/find-stationary-distribution-of-markov-chain-using-stochastic-simulation-gillespies-in-python/
https://youtu.be/3DRdoqhNFrk
Comment: Please describe what you have done, not just your affinity for the solution.
Comment: Would you describe the implementation? Why is it interesting?
Comment: i like it because it works very accurately, and its implementation is very easy the original algorithm is taken from here: https://pdfs.semanticscholar.org/f70e/d6c71bc4a7fa5f4584b8616187b73ade644d.pdf
Comment: It would be more useful to the OP, as well as any future visitors to this question, to have more than just links to code & video.  Try to explain the method that you implemented in your own words and post a copy of the code here.
Comment: well i just converted the gillespie's method to python code:


How can I boost the water pressure in my shower?

Question: How can I boost the water pressure in my shower? I found a few shower heads online that say they can boost water pressure.  Is this possible?
Comment: You can get higher pressure if you're willing to accept less volume. Newer shower heads are better at making less water feel like more.
Comment: What type do you have. How old is the shower head. When was the last time you clean it.
Comment: [This answer](http://diy.stackexchange.com/a/63969/33) might be helpful.
Comment: Possible duplicate: [How can I get my shower head to increase water pressure?](http://diy.stackexchange.com/q/63961/33)
Comment: @Tester101:If the restrictor doesn't want to pop out easily, you can go after it with an electric drill. The result is *most* satisfying.
Answer: You should check to see what the water pressure is coming from the water main. A screw-on water pressure gauge can be connected to your garden hose connection to find out what it is. Ideally you would want to see a water pressure between 60 and 80 psi.
If your pressure is significantly lower than 50 psi from the main, then you will have issues with having enough pressure for most shower heads. If you have city water, you may have a water pressure reducing valve. These are typically installed near the water meter. If your house is equipped with one, take a measurement of the water pressure, and then incrementally tighten the screw and take measurements. If the pressure is too high, you can loosen the screw. You want to avoid water pressure over 100 psi. When the pressure is too high, it can cause damage to your plumbing system.
If you have a pressure issue at the main, this may fix your shower issues. If the main is not the problem, or you find the pressure is still too low, then the problem is somewhere in your plumbing system. If the pressure is good in the tub and sink in your bathroom, then the shower head itself might be the culprit. Unscrew the shower head itself and see if the pressure is good coming out of the wall. If that is good, then the shower head is clogged up and should be cleaned out or replaced. Certain shower heads contain a water saving feature that basically causes less volume of water to come out. They work fine in areas that have excellent water pressure such as cities, but not so much when you are running off of a well. In some cases the water saver part is removable. If it can be removed, then this may also fix the problem. Shower heads are pretty easy to replace. There are ones on the market which are specifically designed for low water pressure. Using one of those may help the problem, but if the water pressure is terrible, you may need to have a plumber inspect your entire system to find out where the problem is.
Answer: Assuming you already have a clean shower head, a new shower head isn't going to boost water pressure, technically speaking. Either the pressure is there or it's not. That being said, it may feel like you're getting better pressure due to the design. It's really trial and error with shower heads and a personal preference, but I have found Speakman to help and use it in my rental properties.
http://www.amazon.com/gp/product/B0018LGZ04?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00
In regards to actually increasing water pressure, that answer is a lot more complicated. Perhaps the water supply pipes to your shower valve are galvanized and rusted? In that case, replacing these with copper or PEX would definitely help. The larger issue is that you may need to replace supply piping as far back as your water main to ultimately resolve the issue.
Does the water pressure seem to change when you're doing other things in the house? Maybe running the dishwasher or washing machine? If so, you may have too many devices plumbed into a single supply line. In this case you'll need to trace the pipes back to the main supply and see how you can either increase capacity or run additional supply lines.


Standard headlight socket type for 2006 Forester

Question: I'm confused. I bought replacement bulbs from Amazon that it assured me were correct for my car. After they arrived I realized they were the wrong socket type. I researched socket types and determined that my '06 Forester has an H1 socket for low-beam headlights, and a 9006 (I guess?) for high-beam. Anyway, I looked on some other sites including TireRack, and several merchants seem to be of the impression that the Forester uses the L-shaped 9006 bulb for its low-beam headlights. So why would my car, which we bought new, have a different kind of socket?
Answer: As to why, who knows what drives the manufacturers decisions. In this case, I would guess it is down to whatever the most convenient/cheapest bulb type is in each region.
But yes, this is normal - my 06 Forester headlights are different again. My dipped beam bulbs are these:

But my main beam are 10k HID units that can only be sourced from Japan!
Comment: So basically even within the same model year Subaru chose to use at least three different socket types for the same make, and nobody knows why?
Comment: There are some obvious answers which could be true, including: they used whatever was most convenient/cheapest in each region
Answer: Aftermarket part application databases are not always correct.  Some vehicles had production changes during a model year.  I've worked on such a vehicle, the bulb books at the parts stores were incorrect.  Well, they were correct, but only for vehicles on the other side of the production change.  The database the dealer parts departments use will have the correct information tied to the date of manufacture.
Rory could be right, too. It could vary by production region instead of manufacture date.  Aftermarket databases are not always set up to model these kinds of corner cases properly.


Why can't the birdcage be cut?

Question: Why does it appear that Doflamingo's Bird Cage is indestructible? What is the different between the strings used in DD's attacks and the birdcage? Why can't Zoro cut the birdcage?
Comment: In the previous manga, Zoro is shown trying to stop the birdcage, but not making any attempt to cut it.
Comment: At this point it is not clear, whether Zoro cannot cut the strings or whether it just wouldn't make a difference to cut them. For example, they might regrown so fast, that cutting them wont do any good. Tbh, it would be strange if Zoro couldn't cut the strings, as they aren't even clad in Haki.
Comment: That was my initial speculation. But if you recall, the birdcage was made from DD's clone. If Luffy can destroy another clone of DD(before engaging with Bellamy) then someone in the same league like Zoro should able to cut it. And how does DD has enough Haki to maintain the birdcage for so long?
Comment: The birdcage is not imbued with Haki though. They are just ordinary (but strong and sharp) strings. To be fair, Luffy was never shown to actually break the strings, just to unravel them. The strings were always kept intact.
Comment: It might also be, that by cutting them, the top might close faster. Zoro might escape, but when the cage closes again, the people inside will still end up dying, but I think we have to wait for next week. We saw Fujitora look up at a given point, so either something is happening with the cage, or Doffy is going to throw some strings spears or something at everyone...
Comment: I think everyone will be moved the SAD factory which is made of kairoseki. But no one knows whether the sea stones can crumble under pressure from the surrounding rubble, although it cannot be directly damaged by devil fruit powers.
Comment: Honestly, I think that the birdcage is really overpowered, and that it's very existence causes plot holes.
Answer:
I don't think it is because Zoro cannot cut the cage that he is trying to push it back. In chapter 270 he was in a similar situation, where he was trapped by the White Cage during the Ordeal of Iron. At that time he says it is completely unnecessary to trap him, because he is not going to run away. Now, with the birdcage, the situation is similar in the sense that he has no intention of running away. Cutting the birdcage or running away, will not benefit anyone with Doflamingo still around. He will try to kill anyone present at the island, with or without the birdcage.
Zoro knows this and knows that the person that will defeat Doflamingo is Luffy, but he does not know how much more time Luffy will need. Therefore to buy Luffy as much time as he can and to prevent as much casualties as he can, he tries to block the cage, instead of cutting it. We have no clue what would happen if he cuts the cage and it will probably require much needed energy, which will probably just go to waste by cutting the cage over and over again, because we all know Doflamingo will keep putting it up again and again.
Now as to your question whether the birdcage is indestructible, that has not yet been revealed up until the latest chapter 787. Other than a few unknown pirates and the meteor from Fujitora, there has not been a single person that has actually tried to attack the cage, not now, nor in the flash-back. Therefore it is hard to say how strong the strings actually are.
Answer: First of all, the birdcage itself cuts. A person not possessing Haki can't even touch the cage. If they try to touch they might get injured.

 Here is a proof:

 Zoro told them to move towards the factory because the factory is made of sea-stone (Kairoseki) as mentioned in the wikia and is immune to getting cut by the threads, but is getting dragged instead. So the question of normal people cutting it is solved. But what about the people who possess Haki?

The threads created by Doflamingo are thin enough to be almost invisible but strong enough to slice rocks, trees and even meteors as per wikia.
There's no person who has attempted to cut down the Birdcage. Since no one has tried, it's probably presumed by the swordsmen like Fujitora, Zoro, Trafalgar and Bastille that it can't be cut.
It's similar to the barriers of Bartolomeo that are indestructible.
Answer: I have 2 theories on why Zoro did'nt try to cut the birdcage.

He never interferes with Luffy's fight just like Luffy will never interferes with his...he could have also chosen to attack Doffy directly now that he's weakened badly and either defeat Doffy or easily buying the 10min Luffy needs...instead he chose to delay the birdcage closing and believe in Luffy eventually defeating Doffy and making Luffy appears as the ultimate hero in stopping both Doffy and birdcage.
Doffy has COC haki and Zoro doesn't. So at this point he can't go up against Doffy nor cut his birdcage.

Personally I prefers the first theory cause it's way cooler and there is the speculation that Zoro possess COC ever since his fight with Monet.
As for Fujitora I believe he could not openly oppose Doffy due to their respective status.
Comment: What about other swordsmen like Law and Bastille?
Answer: I believe that his awakening or conquerors Haki may be directly associated to the birdcages invulnerability, even Fujitora and Zoro cannot cut it. It also may be because doffy's clone, whom he doesn't need to directly control will just continuously set up the cage. My final speculation is that the birdcages center might contract upon cutting a section out of it, making cutting it a bad option.
Answer: Well I believe that zoro still not strong enough to cut the tread, as he said he cant hold much longer againts the thread, and I believe fujitora able to cut the thread but he choose not to. straw hat teams still need training and it will be time skip 2
Answer: Definitely can't be cut. If it could have been it would have been, it was close to destroying the country n killing a lot of people Fujitora would have cut it or attempted it with all the civilians at risk. Imo it's the ultimate death trap. Uncutable razor sharp completely rigid string with titanium like tensile nobodys cutting it or bashing a konobo through it. Mihawk is the only wild card an white beard if he were alive.
Answer: (This is my summary from the evidence and speculation from the rest of this thread)The birdcage was never really a threat to the straw hat crew cause there were people in Dressrosa strong enough to deal with the situation. I think Zoro and Fujitora could cut it but there may be no point as no one knows what will happen if the cage is cut. Sabo, Fujitora and Zoro are all strong enough to not only fight Doflamingo from scratch but at least finish him off after the extensive damage he's taken. The main thing was that neither of them wanted to interfere with the fight. They all knew Luffy would beat him and it was Luffy's fight, they just had to give him the time so to minimize casualties they tried to hold the cage back. The evidence that Zoro wouldn't run from the situation anyway, that he won't interfere with the fight which also goes for Sabo and Fujitora who actually said that they wouldn't interfere at seperate times. The whole situation was shown to be quite a lot more difficult than it actually was. Physically there were a lot of solutions for the birdcage. Either 3 of them could break the cage or just kill Doflamingo.

Why can't the birdcage be cut?


How can I automatically have my Trash emptied when disk space gets below a certain point?

Question: Sometimes my hard drive gets low on space, and various things don't work properly until I empty the Trash and free up some space. I know there are applications that empty the Trash after a set interval—but what I want is an app or script (or other means) to empty the Trash whenever there's e.g. less than 2GB of free space on a given hard drive.
Comment: Why not buy a bigger hard drive? 1TB is well under $100 these days... :)
Comment: 3TB is now under $100.
Comment: And yet (a) they're all still finite, and (b) none of them can be added to the current MacBook Pro.
Answer: I use a third party preference pane Compost that deletes from trash when the disk fills up or if the file has been in trash for a given time.
The original download stopped working for me but I have just found this on the author's site instead of the distributer. Note the author's comment

Compost is in a bit of a state of flux right now. The distributor has moved on to a different market and we wish them well in their endeavors. Additionally, the changes necessary to fully support Snow Leopard have been going through an extensive beta period as a result of the degree and complexity of changes required. Please stay tuned for more information.

So it might not work even from this download
When I updated this I had just installed it on Yosemite and it installed (but not enough time to see if it deleted anything) I have now updated to El Capitan and the installer fails.
Comment: For me it is "Hazel" that I use - wonderful automation tool.
Answer: You could also edit the crontab with EDITOR=nano crontab -e and add a line like
0 * * * * osascript -e 'tell app "Finder" to empty trash if free space of startup disk < 2.0E+9'

Hazel supports keeping the trash under a certain size or keeping items only for a period like two weeks.
Answer: I use CleanMyMac, though there are lots of others that do a similar job. CleanMyMac also cleans cache, etc. Hazel is also good for cleaning out folders that fill up with rubbish quite frequently.
Comment: Link? (10 more to go...)
Answer: That's an interesting question.
I wrote a little shell script that will empty the trash if the available disk space falls before a threshold defined in the script (default is 10 GB but you can change that by editing the script).
Install script

Download this:
http://share.luo.ma/ase/12167/etilds.zsh
Install it to /usr/local/bin/etilds.zsh
Then do chmod 755 /usr/local/bin/etilds.zsh

Use launchd for automatic trash emptying
If you want this to run automatically, I recommend launchd. To do that

Download this http://share.luo.ma/ase/12167/com.tjluoma.etilds.plist
Move it to ~/Library/LaunchAgents/
Tell it to run via launchctl load ~/Library/LaunchAgents/com.tjluoma.etilds.plist

It will run every 5 minutes (300 seconds) by default. You can edit that too.
To uninstall:
delete /usr/local/bin/etilds.zsh and ~/Library/LaunchAgents/com.tjluoma.etilds.plist and reboot.
Notes and Disclaimer

No guarantees or warranty but it works for me. Use at your own risk.
You have to edit etilds.zsh. Read it and you'll understand what to do.
"etilds" stands for "Empty Trash If Low Disk Space" because a) I couldn't come up with a better name and b) it seemed a sufficiently unix-y acronym.
Comment: All the links are gone making this useless
Comment: The links have been restored. I'm not sure why Dropbox stopped serving the old ones, but the new ones are on my own server, so they should be there for the foreseeable future. (If there is a better way to share files on ASE, please let me know.)
Comment: You can include the files directly in your post, maybe shorten the .zsh script down to the essential 5 lines first (and keep the link to the long version). So the answer remains usable even if your site goes down/offline for whatever reason.


How to configure network and the Internet to work with Linux Mint VM?

Question: Today, I installed Linux Mint 13 to try some applications, programs and other good things.
after installing it I don't have network connection.
I tried with all type of network switches and activated Legacy Network Adapter but it didn't work
When I turn it Linux Mint says : Disconnected - you are now offline.

How to configure network and the Internet to work with Linux Mint VM ?

Thanks in advance and please answer soon.
Answer: Make sure your actual computer is connected to the intenet and in the VM settings set the Network Adapter to Bridged.