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Introduction to Starting Scientific WorkPlace

The purpose of writing this post is to give a hand-over-fist short introduction for getting familiar with this fantastic friendly-interfaced Scientific Workplace in a minute. This post will be updated soon later.

Basic Scientific WorkPlace Shortcuts (press letter keystrokes while pressing Ctrl key in the mean time):

Ctrl+R  –  Square root
Ctrl+T  –  Switch between Math fonts and Regular fonts
Ctrl+I  –  Integration
Ctrl+D  –  Display of formulas
Ctrl+F  –  Fraction
Ctrl+H  –  Upper Script  (here, H stands for high)
Ctrl+L  –  Lower Script
Ctrl+alpha  –  \alpha  (the LaTex code for typing
\alpha is \alpha , so basically typing the same symbol or character in Scientific Workplace is just to type “alpha” as well as pressing the keystroke Ctrl instead of typing the backslash \)
Ctrl+infty  –  \infty
Ctrl+9  –  parenthesis ( )

……

For example, to use Scientific Workplace to write formula \int_{1}^{\infty} f(x)dx=1, we type as follows:

Ctrl+I  –> Ctrl+L –> 1 –> Ctrl+H –> Ctrl+infty –> f(x)dx=1

The original LaTex codes of characters or symbols can be shown by moving the mouse’s cursor to that symbol or character button on the top.

We can customize the buttons on the top in our favor by clicking “View –> Toolbars”. Choose all options including “Large Buttons” and “Show ToolTips”. Usually, the options like “History”, “Link” and “Exam” are barely used.

Other things like aligning sentences or paragraphs are similar to how we use WORD to do. Those are pretty easy for us to figure out.

Cons: The header codes set up by Scientific Workplace are bit incompatible with LaTex, so if possible, try to avoid using the Scientific Workplace to design or edit the header of your tex file. Just use some well written templates edited by WinEdt.

Filed under: Miscellaneous , , , ,

On Time Management

The following is the article about time management written by Terrence Tao. Very worthy of save. I usually only cite an article using a link, but this is really good one that I want to keep for in case if Terry Tao deletes the article sometime later.

On Time Management (By Terrence Tao)

Prodded by several comments, I have finally decided to write up some my thoughts on time management here.  I actually have been drafting something about this subject for a while, but I soon realised that my own experience with time management is still very much a work in progress (you should see my backlog of papers that need writing up) and I don’t yet have a coherent or definitive philosophy on this topic (other than my advice on writing papers, for instance my page on rapid prototyping). Also, I can only talk about my own personal experiences, which probably do not generalise to all personality types or work situations, though perhaps readers may wish to contribute their own thoughts, experiences, or suggestions in the comments here. [I should also add that I don't always follow my own advice on these matters, often to my own regret.]

I can maybe make some unorganised comments, though. Firstly, I am very lucky to have some excellent collaborators who put a lot of effort into our joint papers; many of the papers appearing recently on this blog, for instance, were to a large extent handled by co-authors. Generally, I find that papers written in collaboration take longer than singly-authored papers, but the net effort expended per author is significantly less (and the quality of writing higher). Also, I find that I can work on many joint papers in parallel (since the ball is often in another co-author’s court, or is pending some other development), but only on one single-authored paper at a time.

[For reasons having to do with the academic calendar, many more of these papers get finished during the summer than any other time of year, but many of these projects have actually been gestating for quite some time. (There should be a joint paper appearing shortly which we have been working on for about three or four years, for instance; and I have been thinking about the global regularity problem for wave maps problem on and off (mostly off) since about 2000.) So a paper being released every week does not actually correspond to a week being the time needed to conceive and then write up a paper; there is in fact quite a long pipeline of development which mostly happens out of public view.]

Another thing is that my ability to do any serious mathematics fluctuates greatly from day to day; sometimes I can think hard on a problem for an hour, other times I feel ready to type up the full details of a sketch that I or my coauthors already wrote, and other times I only feel qualified to respond to email and do errands, or just to take a walk or even a nap. I find it very helpful to organise my time to match this fluctuation: for instance, if I have a free afternoon, and feel inspired to do so, I might close my office door, shut off the internet, and begin typing on a languishing paper; or if not, I go and work on a week’s worth of email, referee a paper, write a blog article, or whatever else seems suited to my current levels of energy and enthusiasm. It is fortunate in mathematics that a large fraction of one’s work (with the notable exception of teaching, which one then has to build one’s schedule around) can be flexibly moved from one time slot to another in this manner. [A corollary to this is that one should deal with tasks before they become so urgent that they have to be done immediately, thus disrupting one's time flexibility.]

It helps a lot here to be able to honestly and accurately evaluate your work potential (a function of your location, your current level of motivation and energy, your upcoming duties and commitments, availability of resources, and the expected level of distraction) for a given period of time into the future (e.g. the rest of the day): being either overconfident or underconfident about what you can achieve leads to taking on either more or less than you can properly handle, both of which lead to inefficiencies (I have learned both sides of this from direct experience).

While I have a large number of things on my “to do” list, at various levels of complexity, difficulty, and length, when it comes to any task requiring dedicated thought, I try to focus on it exclusively, postponing or shutting out everything else; I find that multitasking only works for me when none of the tasks requires more than a fraction of my attention (in particular, it seems to work best when I am not inspired to do any one particular task). Quite often, these tasks take longer to complete than I have the energy, time, or patience for, in which case one has to find a natural break point (e.g. proving a key lemma in a paper that one is writing up, or writing down a full sketch of some idea that just came up in conversation or on the blackboard or scratch paper) where one can safely set the task aside and forget about it for a while, and be able to resume later without losing one’s place. The thing to avoid is to drop a task when it is only partially finished, without any good “closure”; it then either gets lost, or weighs on one’s mind and prevents one from fully thinking about something else, or has to be redone from an earlier point when one picks it up again. But one doesn’t have to finish each task off completely as it comes, as long as it can be picked up later. A mundane example: when I get around to writing physical letters (usually a low priority, when I don’t feel ready to do serious mathematics), I type them, print them out, seal them in an envelope, and then deposit them in my “out” tray, but I generally don’t mail them (or process any other paperwork in my out tray) until it piles up and I have nothing better to do, at which point I go out and deal with all of it at once.  [I find that a particularly good time for doing this is when my computer needs to reboot or is somehow not easily usable.]

More generally, tasks that require little concentration seem to be best done in batches if possible, while tasks that require a lot of concentration seem to be best done individually, with as few distractions as one can manage.

Related to the point about “closure” is the desirability of being able to chop up an extremely long task into smaller, self-contained ones, ideally each with its own immediate “payoff”.  To give one example: I doubt I would ever attempt to write (let alone finish) the equivalent of my 19 or so lectures on the Poincaré conjecture if I had decided to write one enormous article or monograph rather than 19 reasonably manageable and self-supporting shorter pieces.  (It helped also to “paint myself into a corner” a little bit here by announcing the lectures in advance, and building up some momentum, to stop myself from abandoning the project half-way.)

[One very nice thing about modern text editors, including the one on this blog, is that it is very easy to save a draft at some intermediate stage and flesh it out or polish it later, which greatly assists the task of writing long papers by chopping up this task into a sequence of much smaller tasks, as discussed above.  I am quite impressed by mathematicians from before the computer era who were able to meticulously write out high-quality papers and even books; even with good secretarial support, I would find this extremely difficult to do myself.]

It also makes good sense to invest a serious amount of time and effort into learning any skill that you are likely to use repeatedly in the future. A good example in mathematics is LaTeX: if you plan to write a lot of papers, it makes sense to go beyond the bare minimum of skill needed to jerry-rig whatever you need to write your paper, and go out and seriously learn how to make tables, figures, arrays, etc. Recently I’ve been playing with using prerecorded macros to type out a standard block of LaTeX code (e.g. \begin{theorem} … \end{theorem} \begin{proof} … \end{proof}) in a few keystrokes; the actual time saved per instance is probably minimal, but it presumably adds up over time, and in any event feels like you’re being efficient, which is good for morale (which becomes important when writing a long paper).

There are also many situations in which it makes tactical sense to defer, delay, delegate, or procrastinate on any given task, and go work on something else instead in the meantime; not everything is equally important, and also a given task may in fact become much easier (and be completed in a much better way) if one waits for one’s own skills to get stronger, or for other events to happen that reduce the importance or need for the task in the first place.  My current papers on wave maps, for instance, have been delayed for years, much to my own personal frustration, but in retrospect I can see that it was actually a good idea to let those papers sit for a while, as the project as I had originally conceived it was a technical nightmare, and it really was necessary to wait for the technology and understanding in the field to improve before being able to tackle it in a relatively civilised manner.   [Perhaps this very article on time management is an example of this, also.  There are also a number of other draft articles hidden in this blog that I felt were not quite working at the time, and are awaiting some further inspiration to complete.  It seems that not every idea or topic for an article necessarily leads to a viable end product; cf. "use the wastebasket".]

My final suggestion is to pick some sort of organisational system and make a real effort to stick to it; a half-hearted system is probably worse than no system at all. [A corollary to this is not to try to make an overly ambitious system ab nihilo that one is unlikely to follow faithfully; it is probably better to let such systems evolve over time.] I have my own system involving a PDA synchronised to my laptop, my email account, some in trays, out trays, and other designated spots in my office, and a “reserved” blackboard, that probably only I can understand completely, and I don’t think I can even explain it properly here, but I’m used to it now and it seems to work well enough (though I sure hope nobody ever erases that blackboard!). The choice of system though is presumably a very personal matter and I wouldn’t be able to advise on what would work best for anyone other than myself. But I do find that such systems free up a lot of memory; if I don’t have to worry about what I’m supposed to be doing at 3pm on Tuesday, or what work needs to be done on X, Y, and Z for purposes A, B, and C, I can devote more of my attention to trying to understand a mathematical argument, or proving a tricky lemma, or whatever else I need to work on.  [I also find it psychologically satisfying to be able to physically cross off an item from my organisational system, which can be a useful motivation when one feels otherwise uninspired to deal with something.]

Oh, and one final disclaimer: sometimes one should abandon one’s own rules and allow for serendipity.  There have been many times, for instance, when I had planned to work on something during my lunch hour (grabbing something quick to eat), when I was interrupted by a colleague or visitor to go out to eat.  It has often happened that I got a lot more out of that lunch (mathematically or otherwise) than I would have back at the office, though not in the way I would have anticipated.  And it was more enjoyable, too.  (Similarly with skipping talks at conferences (or skipping conferences altogether) to go work on one’s own papers, etc.)

Filed under: Miscellaneous ,

外甥女的网上小家

小外甥女长的真快,一年过去了,在视频上见证了从爬到走的历程,算是人生第一次见到一个孩子慢慢成长的历程。小外甥女现在有大姐和杜哥在网络安的家了,有兴趣看看我们的小外甥女杜雨霏的成长经历吧。

Filed under: Miscellaneous

Make Unlimited Calls to China Using Skype

Update: The Skype terminated this service for calls to China few months ago. :-(

Great news!! Skype allows users to make unlimited number of calls to China without limitation on calling minutes. You may log on subscription webpage to choose the country you want to call the most. If you subscribe the service of one-year unlimited calls only to China (instead of selecting all countries) from “Unlimited World” on this webpage, then the monthly rate will be reduced down to $4.00/month or so (I know it’s $4 because we purchased it), which is a pretty good deal if you need to call home a lot.

Actually, the so-called unlimited time does have limitation. The bottom of introduction webpage for the “Unlimited World” feature says that as part of fair usage policy, you will get up to 10,000 minutes calling minutes per month (of course, the company hates abuse behaviors), but 10,000 minutes are pretty much about 7 days long. It should be enough for most of people.

PS: If you are sharing this service with some other people, try not to let several people log in the shared Skype account at the same time, otherwise, Skype might suspend your purchased service due to usage abuse because it is easy for them to detect that computers with multiple IP addresses are using the same Skype account.

Filed under: Miscellaneous , , ,

Is BlackJack Dealer Beatable?

I went to watch the recent blockbuster movie “21“, a movie based on the book “Beat the Dealer” written by Professor Edward O. Thorp. There are some apparently factual inaccuracies, such as main characters are supposed to be Asian-Americans in the MIT blackjack team, and professor Thorp wasn’t corrupt as portrayed in the movie. Plus, film directing is little disappointing. Nevertheless, there are several interesting questions mentioned in the movie.

1). Is blackjack really beatable? The answer is YES. I am not an expert on this gambling game, but I believe that it doesn’t really need some disguised signals to cheat like what Ben’s team does. Perhaps the reason is that adding little drama is just part of marketing strategy. The card game strategy like card counting is a prerequisite. There are several websites and books online dedicated to beating blackjack. Anyone who is interested in this problem may visit the website Beat the BlackJack or download the book How to Beat the Dealer in Any Casino to get acquainted with the solutions. PS: Professor Thorp also wrote an article about beating the market (allegedly) in 2003, which might interest people working on quantitative finance.

2). At the beginning of this movie, there is one scene in which Ben gives a brilliant answer to a probability problem and attracts professor Rosa’s attention. This probability problem mentioned by professor Rosa in his non-linear equation class is:

There are two goats and one car behind each of three doors. The host of the show (or game) knows exactly which door the car is behind. You are asked to pick a door first, but the host doesn’t open the door you just chose. He/she opens a door with a goat behind it. Now, you are again asked to choose one of the two remaining doors. If the car is behind the door you choose this time, then you win this car, otherwise, you will get nothing. Now the question is: What should you do? Don’t change the first choice you made or switch to the other unopened door?

Usually, the first thought is that, well, of course, you have two doors to choose, so it doesn’t matter which one you pick, the chance of winning is always 1/2. Actually, this is a simple problem that is not too simple when one is under time pressure. Ben gives a beautiful solution that looks odd at first. To see the answer in the blank space below, you need to left-click any blank space on this webpage, and then press Ctrl+A (the so-called select all command).

The answer is that changing your first choice will give your 2/3 chance of winning. Here is the interpretation. By this tactic (i.e. change the door), if the first door you chose has a goat behind it, which has 2/3 probability, then you will definitely win the car after you make the second choice. But if the thing behind the first door you chose is the car, which has 1/3 probability, then eventually you will lose after you make the second-round choice. Anyway, 2/3 chance of winning is good enough.

The 21 is an overall good entertaining movie. At least, I didn’t sleep away half of time like I did while watching Forbidden Kingdom in theater ^_^.

Filed under: Miscellaneous, The Sciences (non-technical) , , , , , , ,

The Paint “The Last Supper” in Detail

The image of size 172181 x 93611 pixel of famous The Last Supper painted by Leonardo da Vinci is available online. Check out this amazingly clear photo!!

Filed under: Miscellaneous

A Clip from the Movie “The Devil Wears Prada”

The clip (sorry, this clip was deleted from YouTube shortly after I posted this link here due to some copyright violation) from the 2006 comedy-drama movie The Devil Wears Prada caught my eyes recently because this guy claimed it to be the “Best Moments”, which is amazingly the same as I thought. In this clip, the demanding boss Miranda played by Meryl Streep makes Andy run here and do that, and all moments are really hilarious. Anyway, it was quite satisfactory to see that Andy knows where she truly belongs to and gets back to her estranged friends after she sees more and more Miranda in herself and leaves Miranda, job, and fashion behind. The greatest moment is at the movie’s last shot. Andy exchanges look with Miranda after she sees Miranda get in her car, and then Miranda shows the smile (very soft, and the only smile in the whole movie) on her face before she sternly orders the driver “go!!”. What an aftertaste! :-)

Filed under: Miscellaneous

Harry Potter Becoming A Princetonian?

The news about Harry Potter’s actor Daniel Radcliffe getting admission to Princeton University majoring in magic has been widely spread through The Daily Princetonian. I’ve been also looking forward to having such an opportunity to study magic with Harry, and lots of people will have fun studying in this prestigious magic school. Don’t you think so? :-)

Filed under: Miscellaneous

YouTube Videos: Interviews with Feynman & How to “Change” People

My friend gave me two links to the interesting videos about making images on big advertisement boards on roads. Video: Dove Evolution; Video: Parodia. The amazing YouTube also has dozens of videos for legendary Nobel Medalist Richard Feynman giving lectures, etc. There are a series of videos of lectures and interviews, really valuable :-)

Filed under: Miscellaneous

How to Set Up Wireless Network at Home?

This basic instruction is only for setting up a wireless network at apartment using TRENDnet wireless router. Actually, I didn’t know what other options really mean while setting up wireless network by myself because it’s really little time consuming. Anyway, it should be enough for a beginner (hope so :-) ).

Step1: Install the required software from the CD in the package of wireless router.

Step2: Use Internet Browser to log on http://192.168.1.1 to set up everything about router. Usually wireless can be accessible when the router is connected with cable directly. If wireless isn’t connected, then also connect the computer with the router using another cable.

Step3: The default administrator’s login name and password are: “admin”, password: “admin”. Similarly, the default user’s name is “user”.

Step4: The password for administrator who controls the wireless router’s settings can be changed at “Main –> Password”. (Remark: This password is the not for other people who can see this wireless signal to get access to internet).

Step5: The name appeared on the list of wireless signals (which is SSID) can be changed at “Wireless –> Basic”.

Step 6: The password for accessing this wireless signal you just set up can be changed at “Wireless –> Security”. Then, choose the “Authentication Type” to be “WPA”, and “Passphrase” is the the password for other people to surf Internet using the wireless network you set up. (Of course, one can also change the authentication type there)

Remark 1: If the administrator of wireless network forgets the password to all settings, then he/she can reset everything back to factory default settings. (There’s a little hole on the router for reset)

Remark 2: For a D-Link router, there are few things little different. The log in address for setting up the router is  http://192.168.0.1  The default administrator’s name is “admin”, and password is empty (or nothing).

Remark 3: One can choose a channel (1 ~ 11) different from the channels of available wireless signals he/she can receive. This helps reduce the interference of wireless signals and increase the speed, because the less wireless networks share the same channel, the better wireless signal you can get. This article gives 10 good tips for improving your wireless network at home.

Remark 4: To figure out the unique MAC address (the physical address for Ethernet adapter or wireless network adapter) for your computer, one first opens the “Command Prompt” whose interface is similar to DOS from Start –> All Programs –> Accessories –> Command Prompt (or Start –> Run, then type cmd), and then type ipconfig /all . The physical address of the adapter is of the form like 00-13-58-E2-D9-2D.

Filed under: Miscellaneous