O.K. Here's a site I love and I've only spent a few minutes there. It's a site for science hobbyists! Yes. And while it says for kids to stay away, I didn't see anything objectionable. Except to acually conduct any of the experiments. I wouldn't recommend that without adult (intelligent adult) supervision. But, browse throught this site and enjoy. I only have a minute to look now, but I'll be back!
(Tip: Test and Measurement World magazine www.tmworld.com)
Thursday, August 11, 2005
Newspapers: From around the world
The Newseum, a museum for journalism, has a site with frontpages of newspapers from around the world. Go to the link above, and run your mouse over the papers. You'll see the front page. Click on the link and you'll get a window so you can read the front page. It's pretty cool; you can see what's in the news at other locales and see newspapers find important. I noticed that while my paper, The Washington Post, is pretty nationall focussed, especially the front page, the newspaper in Cumberland, MD, is much more locally focused. Interesting to compare!
(Tip: Ilachina and thanks very much.)
(Tip: Ilachina and thanks very much.)
Wednesday, July 27, 2005
Keep searching, you're bound to find something!
The New York Times reports that the space shuttle Discovery had:
" cameras on the launching pad, cameras aloft on planes monitoring the ascent, cameras on the shuttle checking for missing foam on the external fuel tank, and a camera on the tank itself. One camera caught a mysterious object falling from the shuttle at liftoff; radar detected another, about two minutes into the flight. Cameras aboard the shuttle and the International Space Station will monitor the Discovery until the end of its mission."
Ordinarily, more data are better. If you study a "Black Box" you want to probe it with as many inputs as you can, measure the outputs, and try to discern what's inside. The more data you have, the better you can tell something. Not so with Discovery.
As the Times article notes, more data on the shuttle could lead to more worries, more investigations, and more tests. However, such data, while true, may not be cause for any concerns. The fact that a camera discovers something does not imply that there's a problem. Moreover, there may be nothing you can do in any case. And, as if that's not enough, fixing the problem may cause other problems that were not there before the fix!
As the article notes, in medicine a physician can do lots of tests. But oftentimes the tests pick-up items that are irrelevant to patient health, or wouldn't develop into problems until well after the patient is dead. Knowing about them doesn't help the patient. In fact, it may prompt the patient to seek treatment where the treatment side effects are worse then the may-never-to-appear disease.
We have to remember what we learned in school: Sometimes,
Less really is more!
" cameras on the launching pad, cameras aloft on planes monitoring the ascent, cameras on the shuttle checking for missing foam on the external fuel tank, and a camera on the tank itself. One camera caught a mysterious object falling from the shuttle at liftoff; radar detected another, about two minutes into the flight. Cameras aboard the shuttle and the International Space Station will monitor the Discovery until the end of its mission."
Ordinarily, more data are better. If you study a "Black Box" you want to probe it with as many inputs as you can, measure the outputs, and try to discern what's inside. The more data you have, the better you can tell something. Not so with Discovery.
As the Times article notes, more data on the shuttle could lead to more worries, more investigations, and more tests. However, such data, while true, may not be cause for any concerns. The fact that a camera discovers something does not imply that there's a problem. Moreover, there may be nothing you can do in any case. And, as if that's not enough, fixing the problem may cause other problems that were not there before the fix!
As the article notes, in medicine a physician can do lots of tests. But oftentimes the tests pick-up items that are irrelevant to patient health, or wouldn't develop into problems until well after the patient is dead. Knowing about them doesn't help the patient. In fact, it may prompt the patient to seek treatment where the treatment side effects are worse then the may-never-to-appear disease.
We have to remember what we learned in school: Sometimes,
Less really is more!
Tuesday, July 26, 2005
Shuttle launched!
The shuttle Discovery had a successful launch this morning. YES! It's great that the program is moving forward. While flying the shuttle will be a dangerous mission for a long time to come, it's right that we go on to fly more and more. This is good not just for the program itself, but for the country and for everyone, in fact, to see that man continues to explore the universe. We should be expanding our space explorations beyond the shuttle to visit planets as soon as we can. The journey to space is a challenge we should meet.
1 in 100: How do you know?
NASA said the chance of failure with the shuttle launch (that was, in fact, successful YAY!) is 1 in a 100. How do they know that? According to the New York Times, NASA
" combines the findings of flight experience, computer simulations and expert judgment to assess how the shuttle's millions of parts will work or fail in varying situations."
Now this is just bunk. Sure, NASA can test systems and subsystems. Test parts for integrity under varying conditions, but it cannot test the entire shuttle until it flies. There have been 113 flights with two (2) catastrophic failures. It is impossible to quantify just what the chances are (probabilities, if you will) for failure. There just are NOT enough tests to know. That said, NASA still has to decide if the launch should go or not. In the end it's a decision based on little more than guess work.
" combines the findings of flight experience, computer simulations and expert judgment to assess how the shuttle's millions of parts will work or fail in varying situations."
Now this is just bunk. Sure, NASA can test systems and subsystems. Test parts for integrity under varying conditions, but it cannot test the entire shuttle until it flies. There have been 113 flights with two (2) catastrophic failures. It is impossible to quantify just what the chances are (probabilities, if you will) for failure. There just are NOT enough tests to know. That said, NASA still has to decide if the launch should go or not. In the end it's a decision based on little more than guess work.
Science Hotel
The Jerusalem Post reports that Israel has built a hotel for science. Well, not exactly for science but rather, a hotel to house students so that they can learn about science. The cost is free and the idea is that students from the country will stay there and study "life science, physics, chemistry, biotechology, electro-optics and environmental quality."
I hope more countries will follow this example, notably the United States. In fact, this week's Fortune magazine (I'll have to look for the URL; I read this in the print edition) talked of America's need for science to stay competitive. More on that later.
Wednesday, July 06, 2005
Integer Sequeces: An On-Line Look-Up
Here's a fascinating site that I've only just begun to explore. It's an online encyclopedia for looking up integer sequences. Say you have a sequence like:
1, 4, 9, 16
and you want to know what the next number might be. Or, you want to know of a relationship between these numbers. Go to this site, type in the sequence and it'll return:
Well, I thought it would quickly tell me that this is a sequence of squares:
1*1=1
2*2=4
3*3=9
4*4=16
But, that didn't come right back. Instead I got the following:
Triangle giving a(n,r) = number of equivalence classes of Boolean
functions of n variables and range r=0..2^n under action of symmetric
group.
Triangular array T read by rows: T(n,k)=k^2 mod n, for
k=1,2,...,[n/2], n=2,3,...
Triangle T(n,k), 0<=k<=n, giving coefficients when output
sequence O_0, O_1, O_2, ... from transformation described in A059216
is expressed in terms of input sequence I_0, I_1, I_2, ...
Triangle read by rows giving numbers of paths in a lattice satisfying
certain conditions.
Array of coefficients of x in the expansions of
T(k,x)=(1+kx-(k-2)x^2)/(1-x)^4, k>-4.
Array read by antidiagonals, generated by the matrix M =
[1,1,1;1,N,1;1,1,1];.
Define predecessors of n, P(n), to consist of numbers whose binary
representation is obtained from that of n by replacing 10 by 01 or
changing a final 1 to a 0; then a(0)=1, a(n) = Sum f(P(n)), n>0.
The pattern is obvious.
s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (odd
natural numbers)
Squares arising in p=x^2+n, where p is the smallest prime of this form.
Smallest q squares > 0 so that q+n is a prime.
n^2 mod 18.
n^2 mod 19.
Finally, I saw something I was thinking of when I wrote the sequence, although I had not thought of the modular part.
Anyway, even though I got an unexpected answer, the site still looks pretty neat.
By the way, this is an example of what's wrong with someone being asked to "find the next number." If you don't know the rule, then there's nothing to say that whatever rule you want to use is not the correct rule. That is, without a criteria to select the rule, any rule can do. I believe this is the "Ugly Duck Theorem," but more on that later.
1, 4, 9, 16
and you want to know what the next number might be. Or, you want to know of a relationship between these numbers. Go to this site, type in the sequence and it'll return:
Well, I thought it would quickly tell me that this is a sequence of squares:
1*1=1
2*2=4
3*3=9
4*4=16
But, that didn't come right back. Instead I got the following:
Triangle giving a(n,r) = number of equivalence classes of Boolean
functions of n variables and range r=0..2^n under action of symmetric
group.
Triangular array T read by rows: T(n,k)=k^2 mod n, for
k=1,2,...,[n/2], n=2,3,...
Triangle T(n,k), 0<=k<=n, giving coefficients when output
sequence O_0, O_1, O_2, ... from transformation described in A059216
is expressed in terms of input sequence I_0, I_1, I_2, ...
Triangle read by rows giving numbers of paths in a lattice satisfying
certain conditions.
Array of coefficients of x in the expansions of
T(k,x)=(1+kx-(k-2)x^2)/(1-x)^4, k>-4.
Array read by antidiagonals, generated by the matrix M =
[1,1,1;1,N,1;1,1,1];.
Define predecessors of n, P(n), to consist of numbers whose binary
representation is obtained from that of n by replacing 10 by 01 or
changing a final 1 to a 0; then a(0)=1, a(n) = Sum f(P(n)), n>0.
The pattern is obvious.
s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (odd
natural numbers)
Squares arising in p=x^2+n, where p is the smallest prime of this form.
Smallest q squares > 0 so that q+n is a prime.
n^2 mod 18.
n^2 mod 19.
Finally, I saw something I was thinking of when I wrote the sequence, although I had not thought of the modular part.
Anyway, even though I got an unexpected answer, the site still looks pretty neat.
By the way, this is an example of what's wrong with someone being asked to "find the next number." If you don't know the rule, then there's nothing to say that whatever rule you want to use is not the correct rule. That is, without a criteria to select the rule, any rule can do. I believe this is the "Ugly Duck Theorem," but more on that later.
Secure Wireless Technology
Sandia National Labs has recently developed secure wireless technology. According to the article this is a new idea. I am not so sure as to what's new. We now have wireless technology and we have encryption technology for wireless communications.
I think the new area here is that this wireless is ultra-wideband so that it difficult to detect and particularly difficult to jam. Current wireless technology is easy to detect, easier to jam. So, that is something new.
I think the new area here is that this wireless is ultra-wideband so that it difficult to detect and particularly difficult to jam. Current wireless technology is easy to detect, easier to jam. So, that is something new.
This will hurt you more than it'll hurt me
A new study shows that women feel pain more often than men and over more of their body than men.
I always thought this was true but who could say such a thing without being a chauvinist? Now, we "know" it to be true.
I always thought this was true but who could say such a thing without being a chauvinist? Now, we "know" it to be true.
Go Ahead: Exercise!
It's the summer time and exercise is a great way to spend your time. I had thought that jogging would be bad for one's knees, but this article in ScienceDaily notes that jogging isn't too bad on your knees. We all know that exercise is good for you in many ways: better fitness for less illness (exercise helps your immune system), lowers the incidences of depression, release of endorphins that make you feel good, and just generally boosts your spirits.
So, get out and have fun.
So, get out and have fun.
Wednesday, June 29, 2005
How Euler did it: Roots of a polynomial
On the Mathematical Association of America there's a column entitled: "How Euler Did It." The link downloads a PDF file, by the way.
This month, Ed Sandifer writes on a method Euler developed to find a root of a polynomial. The method begins by computing the power series expansion of the reciprocal of the polynomial. Then, we do a partial fraction expansion of this quotient. From the expansion we can set up a recursion. As we iterate the recursion we can find the largest root.
The paper is worth reading.
This month, Ed Sandifer writes on a method Euler developed to find a root of a polynomial. The method begins by computing the power series expansion of the reciprocal of the polynomial. Then, we do a partial fraction expansion of this quotient. From the expansion we can set up a recursion. As we iterate the recursion we can find the largest root.
The paper is worth reading.
Eye Sparkle: Attracts female butterflies
Research at the University of Buffalo shows that female butterflies are attracted to the sparkle of the eyespots on male butterflies. It's not how big the spots are, it's how they sparkle.
Heart Disease: Get's worse as you get older
This story from Sciencedaily.com makes little sense to me. A recent study notes that people are at a higher risk of heart disease as they age. I always thought that was the case even before the study. Here's a quote:
"The results of the present investigation confirm that acute HF (Heart Failure) represents a considerable burden to the health of the community, particularly in older individuals. Given the aging of the U.S. population, and declining national death rates due to cardiovascular disease placing these individuals at increased risk for HF during their latter years of life, increasing trends in the magnitude and morbidity of HF are likely to continue for the foreseeable future."
Isn't this well-know already? What's the point to this study? If you know let me know. Thanks.
"The results of the present investigation confirm that acute HF (Heart Failure) represents a considerable burden to the health of the community, particularly in older individuals. Given the aging of the U.S. population, and declining national death rates due to cardiovascular disease placing these individuals at increased risk for HF during their latter years of life, increasing trends in the magnitude and morbidity of HF are likely to continue for the foreseeable future."
Isn't this well-know already? What's the point to this study? If you know let me know. Thanks.
Monday, June 27, 2005
Numbers in the Wall Street Journal Website
I just signed up for a subscription to the Wall Street Journal on-line edition. I had only visited the site before and saw the headlines, but never could enter the site. Now, I have access and I've found a most delightful column.
The column is:
THE NUMBERS GUY
By CARL BIALIK
and Mr. Bialik goes through various news articles and sites to show how numbers can be misused. If you have access to this site, it's worth a look. If not, I'll quote part of his column below. Look for more quotes as I see them.
--------------- Quote below ------------------
Dean Arthur Schwartzmiller, arrested last month in San Jose, Calif., for alleged sexual abuse of two boys, became the subject of a wider investigation after police found seven log books containing a reported 36,000 entries of sex acts with boys.
It's extremely unlikely that anyone could commit 36,000 acts of sexual abuse -- as Numbers Guy reader Don Fenstermacher pointed out, that would amount to an average of about 2.8 per day since Feb. 12, 1970, when Mr. Schwartzmiller was convicted in Alaska on three counts of lewd and lascivious conduct with three boys. The Daily Herald of Everett, Wash., noted it would take more than two molestations a day over 47 years. Police realized that many of the journal entries could be duplicates, and some may not be describing actual sex acts. "If you assume 10% of them are actual cases, that's 3,600 acts," Lieutenant Scott Cornfield of the San Jose police sexual assault investigations unit told the New York Times last week. "Even if you assume one percent, that's 360 victims." The Times headlined its report, "Child Molester Is Suspected in Hundreds of Cases."
But not all publications were as cautious with the numbers, especially in crafting catchy headlines. Dozens of Web sites headlined an Associated Press report, "Molester Suspected in 36,000 Abuse Cases."
The column is:
THE NUMBERS GUY
By CARL BIALIK
and Mr. Bialik goes through various news articles and sites to show how numbers can be misused. If you have access to this site, it's worth a look. If not, I'll quote part of his column below. Look for more quotes as I see them.
--------------- Quote below ------------------
Dean Arthur Schwartzmiller, arrested last month in San Jose, Calif., for alleged sexual abuse of two boys, became the subject of a wider investigation after police found seven log books containing a reported 36,000 entries of sex acts with boys.
It's extremely unlikely that anyone could commit 36,000 acts of sexual abuse -- as Numbers Guy reader Don Fenstermacher pointed out, that would amount to an average of about 2.8 per day since Feb. 12, 1970, when Mr. Schwartzmiller was convicted in Alaska on three counts of lewd and lascivious conduct with three boys. The Daily Herald of Everett, Wash., noted it would take more than two molestations a day over 47 years. Police realized that many of the journal entries could be duplicates, and some may not be describing actual sex acts. "If you assume 10% of them are actual cases, that's 3,600 acts," Lieutenant Scott Cornfield of the San Jose police sexual assault investigations unit told the New York Times last week. "Even if you assume one percent, that's 360 victims." The Times headlined its report, "Child Molester Is Suspected in Hundreds of Cases."
But not all publications were as cautious with the numbers, especially in crafting catchy headlines. Dozens of Web sites headlined an Associated Press report, "Molester Suspected in 36,000 Abuse Cases."
Tuesday, June 21, 2005
Darwin: You ought to be in pictures. Not.
Seems the radical right is pressuring theaters not to show movies that talk about evolution and Darwin. Evolution is out, intelligent design is in.
Can anyone tell me what intelligent design is? What's the difference between postulating an intelligent designer and postulating God as the creator?
What's more, why is it that religious zealots are so upset over Darwin? He had a theory that sought to explain the origin and development of life. I haven't seen any others that can compete with his so what's the fuss?
Can anyone tell me what intelligent design is? What's the difference between postulating an intelligent designer and postulating God as the creator?
What's more, why is it that religious zealots are so upset over Darwin? He had a theory that sought to explain the origin and development of life. I haven't seen any others that can compete with his so what's the fuss?
Friday, May 27, 2005
Twin Primes: Case closed?
It seems the conjecture that there are an infinite number of twin primes (twin primes are two prime numbers separated by 2, like 3 and 5) has been proved. While the proof is not published yet, the reviewers feel that the authors got it right this time. They had thought they had it right a few years ago, but made a mistake. Now, it seems, the conjecture is proved.
This is quite fascinating if for no other reason that there you can make arbitrarily long sequences of numbers where none are prime. Yet, there are infinitely many prime pairs. Pretty cool, eh?
This is quite fascinating if for no other reason that there you can make arbitrarily long sequences of numbers where none are prime. Yet, there are infinitely many prime pairs. Pretty cool, eh?
Tuesday, May 17, 2005
Los Alamos: Under new management
The contract to run Los Alamos is up for renewal. In the past the University of California ran the lab. Now, contractors are bidding to do the job.
This is a shame, really. Los Alamos, and the other national labs, should be a great source of pride and science for the United States. That any of them could become just another factory saps the life out of what are unique places for research.
I hope the labs maintain their high quality of research and people. They are one of the few places left in America for pure research. If they start to slide toward too much applied research, or (heavens!) factory-like work, it'll mark a definitive end of science in America. Let's hope that does not happen.
This is a shame, really. Los Alamos, and the other national labs, should be a great source of pride and science for the United States. That any of them could become just another factory saps the life out of what are unique places for research.
I hope the labs maintain their high quality of research and people. They are one of the few places left in America for pure research. If they start to slide toward too much applied research, or (heavens!) factory-like work, it'll mark a definitive end of science in America. Let's hope that does not happen.
Women and Orgasms: What's the point?
The New York Times reports on a recent study that claims women have no evolutionary purpose for orgasms. That's right. For men, orgasms are find and dandy. They serve a purpose: it's nature's way to prompt men to have sex and thereby reproduce. In women, though, orgasms are not necessary to reproduction.
Women can have sex and whether they experience an orgasm or not, still become pregnant. Of course, one might think that orgasms for women are important. If men have orgasms to prompt them to have sex, why wouldn't women have orgasms to prompt them to have sex?
Women can have sex and whether they experience an orgasm or not, still become pregnant. Of course, one might think that orgasms for women are important. If men have orgasms to prompt them to have sex, why wouldn't women have orgasms to prompt them to have sex?
Thursday, May 12, 2005
Stamps for Scientists
The United States Post Office now has stamps honoring four outstanding scientists: John von Neumann, Barbara McClintock, Josiah Willard Gibbs, and Richard Feynman.
It's a delight to see such a tribute to the people who have, from their work and imaginations, enriched the lives of all of us.
Read about von Neumann here: http://en.wikipedia.org/wiki/John_von_Neumann
Read about McClintock here: http://www.nas.edu/history/members/mcclintock.html
Read about Gibbs here: http://www.aip.org/history/gap/Gibbs/Gibbs.html
Read about Feynman here: http://www.amasci.com/feynman.html and http://www.feynmanonline.com/
Let's end this posting with a quote from Feynman that I saw for the first time at the site I cited on him:
"Physics is like sex. Sure, it may give some practical results, but that's not why we do it." - R. Feynman
It's a delight to see such a tribute to the people who have, from their work and imaginations, enriched the lives of all of us.
Read about von Neumann here: http://en.wikipedia.org/wiki/John_von_Neumann
Read about McClintock here: http://www.nas.edu/history/members/mcclintock.html
Read about Gibbs here: http://www.aip.org/history/gap/Gibbs/Gibbs.html
Read about Feynman here: http://www.amasci.com/feynman.html and http://www.feynmanonline.com/
Let's end this posting with a quote from Feynman that I saw for the first time at the site I cited on him:
"Physics is like sex. Sure, it may give some practical results, but that's not why we do it." - R. Feynman
Time traveler convention: MIT goes nuts
Here's what has to be the most nutty item I've seen in a long time. What makes it so nutty is not nuts are NOT putting it on. Rather, students at MIT have put on a convention (of sorts) to attract time travelers. The convention has already happened and was a flop. No time travelers bothered to show up. What a surprise.
I think the students have caught the media bug and will do (almost) anything to get noticed. I guess it's not too bad, the idea is kooky but what the hey? I'm sure they had a good time.
I think the students have caught the media bug and will do (almost) anything to get noticed. I guess it's not too bad, the idea is kooky but what the hey? I'm sure they had a good time.
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