Domain: umd.edu
Stories and comments across the archive that link to umd.edu.
Comments · 746
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Dave Akin's Laws Of Spacecraft Design
"35. (de Saint-Exupery's Law of Design) A designer knows that he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away."
Taken from Dave Akin's Laws of Spacecraft Design: http://spacecraft.ssl.umd.edu/akins_laws.html
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Re:The reasons for SSL
That's not true, try it yourself:
- Go to https://www.newsdesk.umd.edu/ (or any other site with a self-signed certificate) and watch Firefox give the error page.
- Click "or you can add an exception..." on the error page.
- Click "Add Exception..." (yes, it's a stupid step)
- Click "Get Certificate" in the window that pops up (yes, also a stupid step
:-) - Make sure "Permanently store this exception" is checked, and click "Confirm Security Exception".
It's done. Now, every time you access the site, Firefox will not ask again, unless the site provides a certificate different than the one you added.
(For the sake of completeness: to remove this exception, go to Firefox preferences, Advanced, Encryption and click "View Certificates". In the "Server" tab, look for the certificate you added and remove it.)
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Re:Utterly meaningless--made of statistical FAIL.
The rightly esteemed statistician R.A. Fisher would agree with you, I think. He was pretty firmly against any statistical analysis which was not done using controlled design of experiments design.
However, using this argument, it is impossible to prove most real-world effects using statistics. The best example of this is the link between smoking and lung cancer. Even after a preponderance of evidence from multiple studies accumulated, Fisher refused to acknowledge a link, because each study had some methodological flaw which allowed some alternative possible explanation for the correlation. There's a description of the debate in the excellent (and very readable) book "The Lady Tasting Tea" by David Salsburg, in Chapter 18. Essentially, the problem here is that there
/could/ be bias due to Mechanical Turk participants being biased in some way. On the other hand, there's no particular reason to think that Mechanical Turk participants' bias will have a particular effect. If the effect here is significant and strong, we would want to repeat this with other populations to confirm the lack of a bias...but the possibility of a bias will pretty much always exist, no matter how many groups of people we study. As we study more, the possibility of bias in each population decreases.Now, I don't mean to say that the author's statistical argument is correct. In particular, I think that he has the tendency (which we all have and fall prey to from time to time) of confirmation bias, of focusing on the evidence which supports the hypothesis we already believe. Here's my analysis, from the numbers provided by the author:
I've posted a quick barplot to illustrate. You can see that other than the "Excellent" category, the tendency is for higher self-reported math ability to actually correspond to a higher tendency to say that yes, the law was violated.
A quick and dirty statistical analysis assumes as its null hypothesis that all four categories (no respondents self-reported as "Poor") are the same: they each have the same probability of voting "Yes" for whether the law was violated. A standard maximum-likelihood estimate for this percentage sums over all the responses, arriving at about a 67% chance of saying "Yes". This estimate does have some variance (it's an estimate, not the truth), but we'll ignore that for the moment and assume it's the correct percentage. Now the question is, if this is the case, what is the probability of getting the 44% (12/27) in the "Excellent" category? If we use a binomial distribution, the chances of getting 12 or fewer "Yes" responses from 27 is about 0.013, which seems to have been the source of the author's conclusion that this result is about 1% likely to happen by chance. However, we should also consider that we have four categories; whenever running multiple tests, you have a better chance of getting a "significant" result just by chance. A standard significance cutoff level is 0.05, reflecting that if something has less than a 5% probability of happening by chance, this is evidence that something other than chance is at work. Since we are running 4 tests, we use a Bonferroni correction, dividing by 4, to get 0.0125 as our actual cutoff. You can see, however, that 0.013 is higher than 0.0125, so it actually does not even (quite) meet the 5% significance level.
As a final note for all the real statisticians out there, it's clear there are still a number of issues with the above analysis (such as the fact that we ignore the dependence between the categories, for example). A chi-squared test provides a value of 8.06, with a p-value around 0.045; however, this is caused about equally by the low "yes" result for "Excellent" and the high "yes" result for "Very good"; that difference, unfortunately, allows for a variety of expl
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Re:Marketing Gimmicks & Flawed Analyses
Actually, it was done a while ago by Compaq. Lousy picture can be found here:
http://www.otal.umd.edu/SHORE/bs05/keyb.htmlThis was around the Pentium MMX/early P2 era, if I remember right. I think it may have been standard equipment on some configs, as I ran across a few of them. Since I almost always hit the space bar with left hand I absolutely hated that keyboard. But if you like the idea, you might be able to track one down.
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Re:Electronic Health Records is very hard
I don't know which particle it would be, but basically cosmis rays can flip bits. Fortunately, ECC will generally correct this--most times--In the below writeup, IBM is advocating why their advanced ECC chipkill is something that would be very relevant for highly critical servers. The big brand servers basically all use chipkill now.
IBM directly seems to be charging for these reports, but the writeup here.
http://www.ece.umd.edu/courses/enee759h.S2003/references/ibm_chipkill.pdf
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Updated information about the sodium experiment.
If you mean the experiment at Dan Lathrop's Nonlinear Dynamics Lab, they are doing succesive experiments with bigger and bigger spheres. Last was with a 60cm one, and now they are working on the 3m version which is the one with 13.5 tons of sodium as you mention. According to their webpage:
The three meter experiment now spins under motor control--watch our YouTube movie! We are debugging the system with water as a test fluid, and will soon make Lagrangian flow measurements in collaboration with colleagues from the group of J. F. Pinton. Sodium experiments will follow. More...
There is an article about them from 2008 at Universe Today, and also other people in France were doing spinning sodium experiments in 2007.
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Updated information about the sodium experiment.
If you mean the experiment at Dan Lathrop's Nonlinear Dynamics Lab, they are doing succesive experiments with bigger and bigger spheres. Last was with a 60cm one, and now they are working on the 3m version which is the one with 13.5 tons of sodium as you mention. According to their webpage:
The three meter experiment now spins under motor control--watch our YouTube movie! We are debugging the system with water as a test fluid, and will soon make Lagrangian flow measurements in collaboration with colleagues from the group of J. F. Pinton. Sodium experiments will follow. More...
There is an article about them from 2008 at Universe Today, and also other people in France were doing spinning sodium experiments in 2007.
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Old news....
This is not a new idea. Actually, this idea has been thought about before and dismissed. The researchers referenced propose using millisecond radio pulsars for navigation. This is a poor idea from an engineering standpoint because it requires having a large collecting area of radio dishes in order to get an apporpriate signal level.
A better idea, which is currently being researched, and was suggested four years ago (at least the earliest I recall it being mentioned) was using x-ray pulsars, which require much smaller collecting area. See for example this thesis on the subject. -
Re:My feedback
Do you know that this idea is clearly not new. Intel TBB provide the same programming model (and much more) for smps and Datacutter ( http://www.cs.umd.edu/projects/hpsl/ResearchAreas/DataCutter.htm ) provide it on grids. That are just the ones I know for working in parallel programming and not even on pratical side of it.
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It seems like data cutter to me
link : http://www.cs.umd.edu/projects/hpsl/ResearchAreas/DataCutter.htm
except data cutter does not rely on .NET... -
Both.
Human being are individuals. They have a genome (well, actually, two, 'cause of the mitochondria), they evolved, they form a population of interbreeding animals.
That said, they provide an ecosystem to a large number of microbial species, some of which are symbionts, some are parasites, some can be both. In general, we cannot live without our symbionts, and our symbionts are depending on us.
All that isn't news. This perspective on a human individual has been here for decades. What is new is that with 2nd generation sequencing it is now possible to thoroughly investigate the microbial composition of our symbionts parasites. This is an exciting new technology which allows such projects as the 1000 genomes project, Neanderthal genome sequencing, metagenomics and much, much more.
Just one more remark: given a population of genetically identical bacteria, it is sometimes wrong to call each bacterial cell an "individual". These cells can collaborate, exchange information, shape their environment and act more like an organism than a single invdividual. There are even some bacteria that can actually get together, differentiate and form a macroscopic, multicellular structure. So saying that we are colonised by 100 trillion of individuals is an exaggeration.
That said, we too can view ourselves as a colony of (mostly: think sperm / eggs and t-cells) genetically identical cells that communicate, collaborate and shape their environment, and also are (mostly, think: blood cells) physically linked together. And each our cell can be viewed as a symbiont between two organisms, each with its own genome and even its own genetic code (yep, the genetic code of the mitochondria differs from that used in the nucleus in our cells).
j. (IAAB)
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Re:Investigative?
Well, they are not spending on their military, that's for damn sure. Oh, and dental care appears to be out too!
The data you're looking for is simple: What percentage of GDP is spend on health care? I cannot find any source that plausibly suggests that the US spends a smaller percentage of its GDP on health care European countries in general. Uwe Reinhart does good work on this topic.
No, I said LESS THAN $400 a month. I've never spent more than that. It may actually cost more than that, but I have a job that helps me pay for my health insurance. So yeah, I'm ignoring my employer contribution...
Well, there's your problem.
...and I know, you are going to tell me that if my employer didn't pay that, they'd pay me more, right? Uh, wrong. Jobs that pay less almost always offer less in benefits, with the exception of temporary or contract jobs.
Let's not compare a job with medical benefits to a job without medical benefits. That's just ridiculous. The question you need to ask yourself is, would you command a higher pay for the same work if your employer didn't have to pay for your health care? Are you suggesting that when they figure out how much they can offer you, that they aren't factoring in the extra several thousands of dollars a year they have to pony up to Blue Cross? If so, I'm willing to bet that you don't believe the same thing about the employer contribution to social security.
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death is scary, a god would be comforting
While there may be a lot of theories that could be devised, that wouldn't mean there wouldn't be a most accurate one.
Here's one that probably works better:
People who are anxious about death tend to flock towards religion more than others.
(Conservatism is highly correlated with death anxiety (r=.50), and religiosity is correlated with conservatism.)
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Physics.
Some simple experiments.
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Re:Tiny balls
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Waterfall was never valid
Dr. Royce used it as an example of a methodology that doesn't work, but what he described was easy to understand so it gained traction with management types. It's like the joke where the guy says he's looking for a lost quarter under a streetlamp because the light is better than where he lost it.
http://www.cs.umd.edu/class/spring2003/cmsc838p/Process/waterfall.pdf
I think his suggestion was to 'build it twice' via prototyping to discover what was missed in the requirements gathering and design phases. -
Re:The Best Job
Nah, they were just lucky. We had a tornado touch down nearby (various reports claimed it was either a F2 or F3 event.) I got to see the damage first-hand. It picked buildings up and tossed them around like toys. We're talking several hundred tons of building that's bolted to the ground. If any of the TIVs get some air under them, they're going to become aircraft
... briefly. -
Re:How much does it weigh in space?
So, if the force of gravity is acting on you, and nothing else is, then you have no force applied to you? You expand my view of the ridiculous....
Yes from the point of view of an outside observer there is a force on you, but the point about gravity is that it applies equally to every part of your body at once. So, if you are in free fall and you raise your arm, there is no resistance to that motion (other than internal friction in your joints) and no force that would push against your arm that would tend to lower it again. From your point of view, you have no forces acting upon you. But this really means that there are not differences in the force between different parts of your body.
This is in contrast to the situation when you are standing on the surface of the Earth, or being accelerated in a car. In the case of standing on the surface of the earth, you feel a force on your body because, while the overall forces cancel out (so you have no overall motion), the forces are applied in different places. The gravitational force is being applied to every atom in your body equally, but the restoring force that is stopping you from falling into the center of the Earth is being applied at the point where your feet make contact with the ground. The restoring force that is stopping some other part of your body (your hand, for example) from falling into the center of the Earth is being transmitted through your feet and body to your hand. That is why it takes some effort to raise your hand - the gravity is acting directly on your hand, but the restoring force to hold your hand in the air needs to be transmitted through your arm.
If you are in free fall, then there is no difference in the force being applied to different parts of your body, and you cannot even tell that there is any force acting upon you! There is no difference between the situation where (1) you are falling under gravity towards the Earth, with no other forces acting upon you, and (2) you are in empty space with no massive objects anywhere near you. These two situations are completely equivalent, for the effects on your body.
Similarly, there is no difference, as far as the forces on your body are concerned, between standing on the surface of the earth and experiencing your weight of W=M*9.81m/s^2 and being accelerated in a rocket ship at 9.81m/s^2 and experiencing a force holding you to the floor of the spacecraft. The Equivalence Principle of relativity says that the forces on you are exactly the same in both cases.
Note that the wikipedia article has, at best, a limited understanding of the difference between weightlessness and freefall. Which are not, contrary to their assertion, synonyms.
They are not synonyms, because they are two words that have different meanings. Wikipedia does not claim that they are synonyms, by the way. But it is true that if you are in freefall then you are weightless. And the only way that is known to physics for an object with non-zero mass to become weightless is to let it free-fall.
If you refuse to believe Wikipedia, there are plenty of other references you could look at:
http://en.allexperts.com/q/Physics-1358/free-fall-weightless-ness.htm
http://www.windows.ucar.edu/tour/link=/teacher_resources/weightlessness_edu.html
http://www.physics.umd.edu/lecdem/services/demos/demosc4/c4-54.htm
http://www.nasa.gov/centers/glenn/shuttlestation/station/microgex.html
http://www.hq.nasa.gov/office/pao/History/SP-4026/noord27.html -
NetGrok
If you liked the Spinning Cube of Potential Doom and AfterGlow, you should check out NetGrok at http://www.cs.umd.edu/projects/netgrok/. It allows real-time analysis of a live packet capture and is released under the BSD license on Google Code. It was presented at the VizSec 2008 conference on security visualization. Disclaimer: I'm one of the project developers.
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Re:Even better
And that partition should have a sub partition
with specs on how to read it
Binary blobs of binary blobs
And so ad infinitum -
Robotic system
There's a better description of the technology from the lab involved here:
http://rams.umd.edu/html/news.shtml#nihr01
'The goal of this project is to develop a novel teleoperated robotic system with haptic (sense of touch) feedback capability that will provide accurate feedback to the physician performing Breast biopsy (Bx) and/or Radio-frequency ablation (RFA) under continuous Magnetic Resonance Imaging (MRI). Some of the primary challenges of this project include: development of a compact robot manipulator, actuation and sensing that is MRI compatible, efficient use of MRI image sequences to guide the Bx needle and/or RFA probe accurately using adaptive control schemes that incorporate soft-tissue properties as the needle/probe traverses the tissue, and an intuitive user-interface which will provide real-time MRI images and Bx needle/RFA probe tracking with respect to the tumor (target) location.'
You don't have to wait for any cells to grow to make use of the biopsy (it can be assessed directly), but obviously a pathologist will have to examine the sample under a microscope before a treatment decision is made.
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Re:Just do what your parents did..30 years of having emails.. that is enough time for two generations. I had an email account back in the 80s.. you also had BBS setups before the "internet".
Care to revise you're statement?
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Re:Flimflammery
Modifying gravity doesn't appear to consistently explain all the gravitational behavior we observe.
In fact, it actually *can't*. Once again, I cite the Bullet Cluster and MACS J0025 results. As this researcher put it, "Nevertheless, the most straightforward interpretation is that there is indeed unseen mass.", and "It does add something new, and that is that whatever that mass is, it is not collisional." Incidentally, his position is that CDM is still not the answer, and that the real solution is a combination of MOND plus some sort of non-interacting mass (eg, WIMPs). But given whatever is there is a) invisible, and b) collisionless, that proves that there's *something* out there that qualifies as dark matter, even if you're unwilling to believe that it is the sole explanation for the missing mass problem.
In summary: for those of you complaining that dark matter resembles aether: you're wrong. It exists. It's existence has been demonstrated in real results. No one credible is denying this fact any longer.
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Repaired link from TFA
The article has a broken link to the original technical presentation. Try this: http://www.iol.umd.edu/Presentations/slideshow.php?id=54
The results here are very interesting. This is different -- and harder -- than the adaptive optics used in ground-based astronomy because the distorting medium is thick, extending all the way to the object being observed. What this implies is that the wavefront distortion isn't uniform across the entire image. So they pick out regions of good (sharp) seeing from each frame, then stitch them together to produce an entire sharp frame. They'll need a fairly fast image processor in those binoculars.
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Re:And Then COBOL 2009
> Well, python+numpy in a single cpu environment can be very fast, depending on what you want to calculate.
So can be MATLAB, as long as it matrix-multiplication, which is practically reduced to a single call to an external C++ library. Java, in contrast, has native implementations of numeric algorithms, which are on par with C(++) ones.
> But you completely miss the point; for really computing intensive work you have to go parallel,
I am well aware of that. I assume you've seen, that the Java version of FFT is, like the C version, running multi-threaded on a single computer. So, I guess you are talking about computer cluster.
In that case, I/O latency and bandwidth should be the limiting factor, which should be fairly language independent. Also, communication should be only a small part of the computation time, which makes the impact even smaller.> and I have yet to see anything in Java that works efficiently in a parallel environment.
Not so long ago, people argued the same way in favour for Fortran over C++, but
as someone put it so eloquently: The absence of proof is not the proof of absence.From what I gather from a quick search: The results of Java MPI bindings didn't look too favourable.
MPJava, however, suggests that comparable performance is possible (within 10% of the Fortran/MPI results in NAS PB Conjugate Gradient benchmark). -
Re:Make it legal to treat them like puppies.
As to where? The homeless shelter?
And those who live where there are no shelters, or where shelters are out of space?
Estimates of the homeless population in Baltimore range from 3,000 to 30,000. Emergency and short-term shelters have about 2,260 beds.
As a practical matter liberal enclaves are attracting them with gold plated homeless services so basically no problem for me (beyond telling the occasional panhandler to 'get a job you parasite').
That's certainly helpful. Do you also go around the cancer wards telling people, "get up, walk it off, you wimp"?
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Re:too bad
"Perhaps we'll see nvidia entering the CPU business some time soon... "
Nvidia *IS* in the CPU business. We call their products GPUs, and we try to limit their use to display adapters, but GPUs are really slightly specialized CPUs. Go on, split the hairs, but it's way more true than false. There is even clustering and app s/w for GPUs.
Not at all a shocker if Nvidia starts marketing a specialized 'C'PU. Something either low power, graphics-enhanced or graphics-embedded, or maybe a one-chip solution. Not that far out of their core competency, though uptake will be harder without a track record.
But Nvidia was not, to me, a mainstream winner in m/b chipsets. SiS has had some good sets, and of course Intel has to be able to make a competitive chipset if for no other reason than to be able to demonstrate their CPUs, ditto AMD.
Perhaps Nvidia is spread a little thin? Now their threat may be that of the one-trick pony. Going into a specialized CPU business may make more sense. They have the GPU->CPU smarts, I bet. Add the chipset knowledge and you get a one-chip ability fairly quickly. Now to find a market. Oh. Sub-notebooks. Or maxi-PDA, or whatever is between an iPhone and a minitablet.
Competition? If only.
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Top three competitors and some videos
Here are the websites for the top three competitors:
The AUVSI's website also mentions that media coverage will be available soon. In the meantime, you can always look at some videos from the SONIA team.
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Tortuga II
You can see some pictures of the winner at University of Maryland's Robotics page http://ram.umd.edu/trac
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Congratulations Scott and Leo!
You guys are awesome! This was only Maryland's second year at the competition, and unlike many of the other schools, it is an undergrad club led effort in design and fundraising.
And the head of the team is a physicist, not an engineer. There's a goofy picture of him with a pumpkin t-shirt on the team's website:
http://ram.umd.edu/ -
Re:The height of irresponsibility
First off, looking back at my post I realize that I sounded too harsh. Apologies for the tone. Coming back to the discussion,
Do you care to lay odds on placing the NP-complete problems in the set of P in the near future?
No, I don't. Because I have no reasonable basis to be inclined one way or the other about it. By the way, my belief is that P!=NP, but that does not make this belief as valid as my belief that fire-breathing dragons do not exist. Both beliefs are qualitatively different. Also, if opinion polls are all that matter, you would be surprised how many great researchers like Bollobas think that P=NP.
In any case, if you want to ameliorate someone's fear about the doomsday scenario (which by the way I don't share), give reasons and not an invalid analogy. Your analogy was invalid and that was my point. My reply had nothing to do with how reasonable or unreasonable GP's fears were.
You could have written whatever you wrote in the previous post when replying to GP, and your arguments about the state or the art being the best possible solution, or how society handles protocols when flaws are discovered would have made for a much sensible post. A valid (or at least reasonable) conclusion does not automatically validate whatever reasoning you might have made to arrive at the conclusion.
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algorithms patentable?
everyone seemed to agree that the algorithm was patentable
That's an odd thing to agree upon, because algorithms are not patentable (search for `algorithm')
But methods are. I forget where I read this, but the difference was explained something like this --
Bob: So, algorithms are not patentable and methods are.
Lawyer: Right.
Bob: But what's the difference between an algorithm and a method? Aren't they pretty much the same thing?
Lawyer: Listen carefully ... algorithms are not patentable, but methods are ...
Bob: ? -
Re:Viewable videos
http://epoxi.umd.edu/4gallery/Earth-Moon_vid.shtml You can view the animated gifs in your browser.
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Re:Haven't they heard?
Either way, the population isn't going anywhere (until the pubs cause wwIII), so we should NOT be using food grade arable land to grow biomass for fuel.
Europe currently has negative population growth. It's not unreasonable to expect the rest of the world to follow suit over the next century or so. While I wouldn't expect a precipitate fall in population, growth should level off (see http://www.census.gov/ipc/www/idb/tables.html for recent history and some projected statistics for the next forty years).
Your point only applies if we get to the point of having a shortage of food grade arable land. If we're only using 50% of the potentially arable land, this doesn't seem like a long term problem. What we're hitting now (causing increasing food prices) is that it is not free to start cultivating the land because the infrastructure is not there. I.e. we're facing short term shortages rather than actual long term limits.
It's also worth noting that the US uses significantly more grain than other countries. The global average is one pound of grain per day, but the US uses five. If the US backed down to two pounds of grain per day, that would still leave three pounds of existing grain that could be used for biofuels.
It's also worth noting that biofuel produced from waste (e.g. the stems and stalks rather than the edible grains) can actually make food cheaper (by increasing the effective yield per acre or hectare and better amortizing the cultivation costs).
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Re:Not just a boon,
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Re:You know who I feel sorry for?
The Polar Bears. No place to go any more.
That actually makes me wonder though... since polar bears have been around for a couple of hundred thousand years or so, what did they during the periods when the planet was warmer than it is today?
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Re:hmmm.
Youtube really messed up the video conversion. The original (much smoother) video in QT format can be found on the project site: http://www.cs.umd.edu/~nchen/reader/
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According to the web
Tin Whiskers appear real:
http://nepp.nasa.gov/WHISKER/background/index.htm
http://www.calce.umd.edu/lead-free/tin-whiskers/
From what I can tell from these links there issue is still present in lead-free solder, and very much an issue in certain conditions. I have not seen any pages which indicate long-term solutions, though it would be interesting if someone can turn one up.
Another link:
http://www.national.com/analog/packaging/leadfree -
Re:Java????
Because Java has a very well defined memory model, that describes how threads interact through memory.AFAIK, there is no similar definition for C++ or C. It depends on the underlaying hardware
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Software Psychology
It just figures that Wikipedia does not have an entry on it. Most colleges don't teach it any more, or even how to write standard code and debug programs anymore. It is starting to become arcane knowledge and a dead skill like Latin, DOS/VSE JCL, or PL/1.
Software Psychology is very important and Apple does it much better than Microsoft does it. Linux and Unix in general do not even try to follow Software Psychology and just are written for computer geeks with commands like "kill" that go against what Software Psychology teaches. -
Re:In short, YMMVFirst; I agree with some of the things you say. But I have to disagree on the following: Other examples include more mundane stuff like the tools recommending that you synchronize or un-synchronize a getter, even when everyone understands why it's OK for it to be as it is.
E.g., a _stateless_ class as a singleton is just an (arguably premature and unneded) speed optimization, because some people think they're saving so much by a singleton instead of the couple of cycles it takes to do a new on a class with no members and no state. It doesn't really freaking matter if there's exactly one of it, or someone gets a copy of it. But invariably the tools will make an "OMG, unsynchronized singleton" fuss, because they don't look deep enough to see if there's actually some state that must be unique. A unsynchronized singleton is not a problem on a singlecore CPU system. But it may fail on SMP system or on a multicore CPU system, and when it does fail, it may do so spectacularly.
I'll explain: You create the unsynchronized singleton on CPU1. CPU2 now retrieves the singleton. But it's possible CPU2 has out-of-date cache on the memory that is occupied by your singleton. If that happens, your singleton will not work correctly.
Don't create a unsynchronized singleton. Either synchronize; or create the singleton in a static initializer; or just call new anytime you need a instance of that class.
A link to a related problem:
http://www.cs.umd.edu/~pugh/java/memoryModel/DoubleCheckedLocking.html
You may believe I'm wrong on some subtle point, or for some particular use case. I'm not. In Java, do not use a unsynchronized singleton on a multithreaded system. -
Seems a little presumptuous...
So the ability to grow a beard in the first place is a prerequisite to success in creating a programming language? I'm sure Smalltalk co-creator Adele Goldberg, among others, would have something to say about that premise.
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Re:DDT
So can you cite a reliable source for this story? It still sounds like an urban legend that has been contoured to fit Mr Lovins political theories.
University of Maryland Listserv has a message with the part from Lovins' "Natural Capitalism". Both provide the message and the book provide the sources they got the info from:
"Cheng, F.Y. 1963. Deterioration of thatch roofs by moth larvae after house spraying in the course of a malaria eradication programme in North Borneo. Bull. WHO 28:136-137."
"Conway, G.R. 1969. Ecological aspects of pest control in Malaysia, pp. 467-488 in Farvar, M.T. and J.P. Milton, eds. The Careless Technology. Natural History Press, New York, NY."
"Harrisson, T. 1965. Operation cat drop. Animals 5:512-513."Try googling for just "thin egg shells lead" instead of leaded gas
Ok, I used leaded gas because that's what you used. Dropping "gas", wow too many results. Try thin egg shells lead birds OR eagles OR falcons, some of the first results were about fish eggs. The second result is from University of Southern California, The Brown Pelican which blames their "population decline and the threat of extinction" on DDT but says nothing about lead. Going through 8 pages of results looking for science or university, college, links I didn't find any saying or suggesting lead had anything to do with thin egg shells. You may wonder why I only checked science or educational links. That's because I wanted scientific links. Ah, here's one although how qualified it is I don' know. Anyway here's what ScienceMaster says on the influence of lead:
"In addition to the adverse effects of DDT, bald eagles also died from lead poisoning as a result of feeding on hunter-killed or crippled waterfowl containing lead shot and from lead shot that was inadvertently ingested by the waterfowl. (In 1991, a 5- year program to phase out the use of lead shot for waterfowl hunting was completed by the U.S. Fish and Wildlife Service.)"
I don't discount heavy metals and other things can affect egg shells, however I also think DDT does as well. I also believe spraying DDT to exterminate mosquitoes, and exterminating them, does have unforeseen cascading effects. Such as killing parasitic wasps, which allows their prey wood eating caterpillars to increase their population.
Perhaps I've been going through this the wrong way as I don't oppose controlling mosquitoes, what I oppose is how they are controlled and what causes their numbers to increase. Studies, including a United Nations study, concluded mosquito populations increase where dams are built. And the economic reasons for dams have been shot down as well. Dams cost more than they were originally sold as costing and the benefits are less than they were sold for. The study Incidence of malaria among children living near dams in northern Ethiopia: community based incidence survey" shows the incidence of malaria in children is significantly higher, sevenfold, near dams than away from them. WCD To Study Brazil's Tucurui Dam and Amazon/Tocantins River Basin says dams are "creating a vast reservoir in which disease-bearing mosquitoes breed". Methods of controlling mosquitoes, other than not creating places they can breed, are available. Though not used alone, bats can help control mosquitoes. As can birds, frogs, and lizards. From University of Florida:
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Bring on the robots!
Humans are, fundamentally, abysmally unsuited to survival in space. Plus, we insist on bringing astronauts BACK, which makes every manned mission FAR more complex and expensive.
Human spaceflight may be romantic and inspiring, and a human may be far more flexible and adaptable than any robot, but humans also have outrageous supply and environmental demands. It's simply impossible for manned missions to do more than a tiny fraction of what far cheaper automated probes can do.
And every time NASA shoots a Shuttle into low orbit to feed the ISS so that it can be dropped into the ocean on schedule, they do almost zero to advance human knowledge, and spend enough money to send a whole new robot-rover mission to Mars and then run it for three months.
People who insist that manned spaceflight is worth the price do not, I think, usually comprehend the magnitude of the difference between that price and the price of unmanned probes. They also seem to have a pretty poor grasp of what space science actually entails, and how little of it even theoretically can be done by people. -
Re:You know who can't do math?
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Re:List your project
Cool idea (although I'm more in the Free Software camp than the Open Source one, but what the hell, we can all be friends). Here's my stuff:
ZEUS-MP -- Not originally mine, but I've done a lot of work on it and released this version of an older parallel MHD code for astronomy.
Misc. Free stuff -- bunch of perl and python scripts along with some LaTeX macros (including one for making business cards).
Sadly, with all the work trying to finish my dissertation these days I haven't updated anything in a while. -
Re:List your project
Cool idea (although I'm more in the Free Software camp than the Open Source one, but what the hell, we can all be friends). Here's my stuff:
ZEUS-MP -- Not originally mine, but I've done a lot of work on it and released this version of an older parallel MHD code for astronomy.
Misc. Free stuff -- bunch of perl and python scripts along with some LaTeX macros (including one for making business cards).
Sadly, with all the work trying to finish my dissertation these days I haven't updated anything in a while. -
1001 tabs
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Not conservative judges
The concept that corporations have ANY "rights", including free speech, is completely ludicrous.
Well, just because you don't like corporations doesn't mean they shouldn't have rights. A corporation is merely a legal business entity created by law, a long time ago, in a representative democracy (or do you only believe in law when it goes the way you want?), to represent the interests of people - you know, the investors. Corporations weren't created to take their rights away because they merely chose a different investment vehicle! Quite the contrary, the whole point was so people can get together and combine and raise capital in a limited liability way. Corporations weren't designed to say, "hey, we have a new way to invest your money, but you lose all of your rights from a sole proprietorship or a partnership." No, the corporate entity was added to further protect investors! Why should someone lose rights merely because they incorporate and get larger and more successful? Simply because you don't like successful businesses? Should we have remained a third-rate power and never grown into this economic powerhouse? Are communist countries really better?
The activist Conservative judges gave corporations some of the same "rights" as people
It wasn't conservative judges, Sparky, that gave Corporations free speech rights. Quite the contrary, the most liberal court in the history of SCOTUS, the Warren Court and the 1970's court in the years thereafter that gave us Roe v Wade and countless other liberal activist decisions, handed down a bunch of decisions that set the corporate free speech rights precedent and more. See:
THE RIGHTS OF CORPORATE SPEECH: MOBIL OIL AND THE LEGAL DEVELOPMENT OF THE VOICE OF BIG BUSINESS
The most significant case, FIRST NATIONAL BANK OF BOSTON v. BELLOTTI (1978), in which the Supreme Court held, in Kerr's words, that "speech otherwise protected by the First Amendment did not lose its protection because the source is a corporation," passed by the same Court that gave us the unprecedented liberal activist case Roe v. Wade, was one in which future "conservative" Chief Justice Justice Rehnquist dissented.
through a grave misunderstanding of the term "people" in the Constitution, because apparently Conservatives think corporations are more important than actual living, breathing PEOPLE. You know, the new type of hairless talking monkeys. That kind of people!
You mean the creatures that actually own corporations, the investors? You do know that over 2/3 of publicly held stock is owned by the individual investor, either directly or through investment funds? And as one of those investors, I like my chances better if a big corporation with its huge resources is advocating for me financially, rather than little me, squeaking away, unheard!
I can't believe you have me defending corporations here. I just reported the law, cheesemonkey! Don't shoot the messenger! -
Run Community Projects
BOINC, Tor, Freenet and/or I2P are good examples of things you can put your extra resources to some use. Here are the BOINC projects I would run if I had 100's of system's at my disposal.
Artificial Intelligence System, NanoHive@Home, Predictor@Home, Project TANPAKU, Spinhenge@Home, The Lattice Project, World Community Grid, SIMAP, Malaria Control, Proteins@Home and Rosetta@Home.