Saturday, December 13, 2008

Defeated



This is the gas valve from a Yugoslavian SKS I J.B.Welded into the gas block. When I got tired of banging my head against my desk trying to make my code run fast, I went into the living room and banged a hammer against a punch [and against my fingers] to remove this reluctant part so I could replace it.

Strangely, the difficulty was not that the J.B.Weld refused to give; I achieved small motion early on. Rather, the simple matter of non-zero volume wedging the part against the gas block walls made extracting it difficult.

Advice: attempting to join parts that were intended to be separate limits your options in the future.

Advice for those who ignored first bit of advice: buy a good selection of punches now because you'll need them. Drill a small pit in the part you're trying to separate, then use the correctly sized punch so you don't damage the surrounding material. Avoid stressing things like barrels by properly supporting the job with wooden blocks or substitute.

Native Client and Alchemy: Software as a Service?

Not so long ago, Google announced Native Client which describes a way in which a browser may execute native instructions in secure sandbox. The natively executing code would run at full speed, and the sandbox would provide a platform-independent layer of abstraction so applications targeting whatever framework was distributed with Native Client The Product (tm) could run on Mac, Linux, or Windows. The paper linked from the "NaCl" page describes the security measures taken to ensure natively executing code can do nothing harmful. Presumably, just running a NaCl browser on a Linux, Windows, or Mac system as a user with minimal privileges to the file system and other resources is already sufficiently secure, but the sandbox protects the browser process as well.

Previously, Adobe announced Alchemy leveraging the Low-Level Virtual Machine bundled with the Flash player as a way to run C++ applications at near native speed with the safety of executing in a virtual machine and dynamic compilation framework. LLVM has the added benefit of being a mature project with fairly robust and well-designed development tools and runtime features.

The commonly cited application for these frameworks is "to run Quake in a browser!" While interesting in its own right, a conversation with Uniquely Joe sparked the idea that perhaps this offers a new business model for software development. Instead of buying shrink-wrapped software in a box, or downloading a torrent from your favorite pirate search engine, you simply log into your software account provided by Adobe, Google, Microsoft, or other, and use the applications you've purchased a service plan for. This benefits you because you don't have to worry about maintaining all of these software installations on the several computers you may work from, software upgrades are more seamless [perhaps less expensive for each subsequent version but now there are many more versions though only your checking account really notices], and perhaps there is a security benefit too if most of your applications run in some sort of sandbox.

This benefits software publishers because distribution costs diminish as there are no shrink-wrap boxes to produce, revenues are more constant due to the service-oriented usage model, you can push advertisements to your users and probably achieve better product integration, and you can curtail piracy since presumably you could build in a cryptographic certificate to prevent execution of your application except where authorized by your license server. With everything running in a sandbox with a uniform abstraction layer on all architectures, testing and support costs should also diminish. As we learned in CS 8803, dynamic compilation frameworks are able to perform many optimizations at runtime that enable an application to [eventually] achieve high performance tuned to the actual system on which it is executed. 'Application + dynamic optimizer' is clearly parallelizable so additional processor cores should reduce the impact of dynamic translation overheads.

Will consumers like it? While some won't even notice a difference, many might be attracted for the reasons previously listed. If Adobe can count on users having LLVM installed, or users willing to install it, it may take this route exclusively. How many people would be willing to eschew Adobe's impressive productivity suite in favor of the disjoint FOSS projects out there?

Comments welcome.

Thursday, December 11, 2008

GPU QR

My GPU QR algorithm achieves a 10.8x speedup over the native MATLAB QR for large matrices. This is faster than I have seen anyone report by far.

I'm working on an Intel MKL testbed application, as that's probably the fastest QR available for x86 and is the ultimate reference implementation.

Thursday, December 4, 2008

Organization of Knowledge

I clicked through to this page on Wikipedia. Clearly, pages like this are useful. I'm pretty sure any good PhD student, by the time they're ready to propose, should be able to sit down at Rocky Mountain, drink several pints, and rattle off something similar for their field.

Saturday, November 22, 2008

News from the GPU VSIPL Front

We're planning to undergo talks for licensing GPU VSIPL. Presently, we only distribute the binary and insist it not be redistributed. This lets early adopters test it out but minimizes the scope of what we're committed to supporting. When the implementation is stable and complete, we're hoping to make it available in some additional capacity. Ideally, we would partner with someone and include it in a larger VSIPL distribution.

Additionally, I'm responsible for implementing a sample application to publish at CUDA Zone. I need a team of undergraduates to finish the Test Suite for me.

Friday, November 21, 2008

Wii on PS3

Someone should implement a Wii virtual machine for PS3.

This should include a hardware receiver (and drivers) for the Wii controllers. GameCube compatibility could be accomplished by translating the inputs from the PS3 controllers into what appear to be GameCube controller signals.

The Cell B.E. processor includes a 64-bit "Power Processing Unit." The Wii's CPU is also a POWER implementation. They both use GPUs developed from the same technology that goes into PC GPUs, so I would expect the PS3 to implement whatever primitive shader model is offered in the Wii. Moreover, I would expect the performance advantage of the PS3 to be sufficient to emulate any hardware-provided functionality in the Wii (use the idle SPUs for dynamic translation!).

Nintendo could continue to sell Wii games, and they'd penetrate formerly PS3-only households. I'd wager the technical obstacles to this idea aren't insurmountable.

Thursday, November 20, 2008

Cells and PS3

Guess the PlayStation3 was simply ahead of its time.

We're in the process of building a system that, if talks go well, will have several high-end (9800GX2) GPUs, one Cell processor, and one quad-core x86. I have no plans for tossing in a Blu-Ray player though that would be amusing.

Wednesday, November 19, 2008

GPU VSIPL

GPU VSIPL is getting some press:

http://www.marketwatch.com/news/story/Mercury-Computer-Systems-Unveils-Multi/story.aspx?guid={A3EA2E33-A633-4021-A6C5-CFB83FBAC70B}

Here is a link to the main GPU VSIPL page, where we claim speedup of two orders of magnitude for applications well-suited to GPUs without ever writing any GPU code.

http://gpu-vsipl.gtri.gatech.edu

We just released a new version on Sunday with a number of enhancements from VSIPL Core, though we do not yet claim VSIPL Core compliance so I will not enumerate them yet. That will come by Christmas.

Monday, November 17, 2008

Sunday, November 9, 2008

SSE3 and Manhattans

Now that the semester's coding for the PTX to SPU translator is complete, I spent the weekend researching some areas that I've been thinking about but haven't had much time to investigate. So, it was a weekend spent mostly* hacking.

1.)
Streaming SIMD Extensions are a set of instructions added to the x86 instruction set beginning with the Pentium II. These instructions apply the same operator, typically floating-point {*,+, -, /}, to corresponding elements of 128-bit 4-element vector registers. Since they are parallel, you can typically perform more operations in a given number of clock cycles than with scalar floating-point code.

SSE2 and SSE3 are revisions that have added additional instructions as programmers demanded them. If you have a Pentium 4 Prescott or better, you have SSE3. If you have a 2.2 GHz P4 Northwood, you only support SSE2, and you miss out on the faster-better-cheaper possibilities concomitant with SSE3.

I spent a few hours updating my hand-rolled matrix class with compiler instrinsics (statements with the semantics of C functions but direct correspondence to CPU instructions; portable too), and I achieved 2.5x speedup for matrix multiply. SSE3 provides support for horizontal operations - operators apply to elements within the same 128-bit register. This permits the implementation of dot products and complex arithmetic without shuffle instructions and makes the code a lot faster. If your CPU doesn't support SSE3, you should probably build a new system (and use the existing system as a dedicated build machine).

2.)
CUDA is interoperable with OpenGL and Direct3D9. I spent a few hours tonight writing a quick DirectX application that renders a textured quad then performs post processing (separable 2D convolution) with a CUDA kernel. The immediate application of this would be to produce efficient visualizations for GPU-based simulations. Other ideas are to perform 3D rendering with DirectX and post-processing image-space operations with CUDA though Cg/HLSL is still probably the right way to implement that.

Also, the fragmented nature of OpenGL distributions across versions and driver providers made it more of a debugging hassle to get working than CUDA-DirectX interoperability.

3.)
Identified the need for a new power supply. Apparently, a GeForce GTX 280 has been purchased for me. I'd like to use it along with the GeForce 9800 GX2 giving me a grand total of 3 GPUs and 2 GB of GDDR3 memory. I'm working on ways to leverage all three at once, so this isn't a fool's errand. Unfortunately, my power supply cannot source enough current on enough lines to power both cards. During Christmas break, I'll make the transition.

*
During a trip to Harry and Sons, I decided to modify my usual order of Chicken Larb (Thai salad). I still ordered it, but I augmented it with a Manhattan. For those of you who don't know, a Manhattan is a cocktail of whiskey and sweet vermouth. Typically, I avoid cocktails because (1) I'd only really had bad examples and (2) cola + {rum, whiskey} is difficult to beat. The stigma of cocktails being girly drinks may have originated during my freshman year's first experiences with alcohol; vodka, grenadine, and orange juice are simply not something I'll ever combine again.

A well-made Manhattan, on the other hand, is quite strong yet simple enough to order from a busy bartender. In terms of flavor, it is quite divine. The vermouth dulls all of the whiskey's edge leaving only the wonderful caramel flavoring. Typically, it's made with 3-4 shots of the principle, so one drink takes you a long way toward inebriation while looking classy the entire time. It's my new official drink.


CUDA, DirectX9, SSE3, and the Manhattan cocktail: all for the win!

Saturday, November 8, 2008

PTX to SPU Translator

Our semester project for Dynamic Compilation and Managed Runtimes is a code translator from NVIDIA's PTX virtual assembly language to IBM Cell SPU. Last night, we just demonstrated it by translating a kernel that computes the complex Givens rotation of a pair of values. The resulting Cell SPU assembly source was linked with a runtime platform we developed, and I executed it on the Cell processor of a PlayStation3 in PaSTEC, my favorite cluster.

We'll be writing a paper due in December that I'll post. Additionally, we'll continue it through next spring. Exciting.

Monday, November 3, 2008

Congratulations, Joe and Sara!

Joe and Sara are now married in an exceedingly elegant wedding ceremony and reception.

First post.

Thursday, September 25, 2008

HPEC 2008

The conference is over, and my talk completed. It went well.

Still no Erdos Number. Need to think more.

Saturday, September 20, 2008

GPU VSIPL

I've released GPU VSIPL: http://gpu-vsipl.gtri.gatech.edu.

After HPEC 2008, I'll upload slides and the extended abstract we will present at the conference. Additionally, we plan to include our own test suite, extended coverage of VISPL Core Profile [matrices, linear algebra, and signal processing functions in 1- and 2-D], and a document on writing high-performance VSIPL applications with GPU VSIPL.

Exciting times.

Friday, September 12, 2008

Cluster Names

In a meeting today, we got onto the topic of project names and then computer naming schemes. Any new cluster needs unique and memorable identifiers for each machine. Numbers are too sterile, so clever administrators strive to select a theme capable of generating thirty or more unique names that still convey membership of the group.

Ada suggested the "vogue" cluster with nodes named after designers. We then sat around tossing out ideas for the GPU cluster being proposed. Here were several of the more amusing ideas

* dead comedians (already in use by CoC)
* high-end automobiles
* Disney characters
* 3rd world dictators

Here are a few more to have on hand in case I ever need them:

* coffee terms (already in use by emma+andy)
* classic video games
* characters in Les Miserables (spelling might be prohibitive, and eponine can be expected to crash before your simulation ends...)
* characters in practically any classic novel (Catch22, Whuthering Heights..)

Audience participation: add to the list.

Saturday, September 6, 2008

Wireframe

I spent some time tinkering with the HTML canvas tag and got this working in not too much time: wireframe cube. Reminds me of high school.

That said, it's odd it took the web this long to include a 2D rendering target that's less sophisticated than GDI+.

Friday, September 5, 2008

Backx0r

As many of you know, I bike from this apartment to school. It's a fun ride that has just enough hills to make each commute a workout. Consequence: I get roughly two 15-minute periods of vigorous exercise every weekday whether I want it or not. With showers in the CRC and a change of clothes on hand, it's fairly convenient.

Several things that aren't, though, are the gates at this apartment complex. They are triggered by induction loops, coils of wire embedded in the pavement that detect vehicles by measuring the change in inductance of the loop when an electrical conductor passes near by. The rear gate is especially challenging since repaving has hidden the coils, and I believe it is not particularly sensitive.

However, a bit of online research and a brief experiment have changed all that. I can open it with impunity now. No need for bizarre aluminum blocks taped to my feet.

--

School and research are going well. I'm involved with a new lab doing research into heterogeneous multicore systems. Additionally, I'm taking GPU VSIPL to dizzying new heights with support for matrices and various linear algebra solvers all getting more than 20x speedups from your trusty GPU. Additionally, in 20 short days, I'll be presenting an awards paper at HPEC 2008. This makes me nervous.

Coolest class ever: Dynamic Compilation. Our semester project will be CUDA=>IBM Cell/BE translator. Stop laughing.

--

I'm taking some time to organize all the code I've written in the past that may be effectively reused. Stand by for libkerr and kerrutils.

Tuesday, August 5, 2008

Tuesday, July 22, 2008

Property Allocation

So, the rigors of four independent people sharing one refrigerator and kitchen have finally caught up with this house. All de facto boundaries of personal "spaces" within our fridge have disappeared in the previous weeks. Finding my cream pushed behind someone's leftovers and spilled has empowered me to speak out.

I'm working on a solution for this and the other common spaces problem. People have laid claims to their storage areas, some of which are unreasonable. People leave dishes in the sink, also unreasonable. Messes get ignored and grow as a result, unreasonable.

What have the readers of this blog implemented when sharing living spaces with people you weren't sleeping with? Any pitfalls? How did you keep dishes out of the sink?

Oh, and the first person to cite Garret Hardin's specious "Tragedy of the Commons" gets a cock punching. We're not talking about sterilizing human beings to keep the Earth from being overpopulated. We're not even talking about consuming commonly held goods. I'm just designing a workable attitude toward property rights with respect to space and time to avoid inefficiency and to prevent people from resenting and hating the others. Perhaps it's a little late, but it's a good experiment.

Monday, July 21, 2008

Golub and Van Loan wear the clock so you can know the time

Just thought I'd share the magic.


U =
[
0.3594 -0.5577 0.5229 -0.4077 0.3128 0.1494 ;
0.4158 -0.4082 0.0545 0.4089 -0.5689 -0.4082 ;
0.4449 -0.1494 -0.4741 0.4072 0.2794 0.5577 ;
0.4449 0.1494 -0.4729 -0.4093 0.2786 -0.5577 ;
0.4158 0.4083 0.0558 -0.4076 -0.5697 0.4082 ;
0.3594 0.5577 0.5216 0.4088 0.3135 -0.1494 ;
];

B =
[
-30.5509 -0.0006 -0.0000 -0.0000 -0.0000 0.0000 ;
-0.0000 -7.4641 0.0001 -0.0000 -0.0000 0.0000 ;
-0.0000 -0.0000 1.7912 0.0035 -0.0000 0.0000 ;
0.0000 -0.0000 0.0000 1.0000 0.0008 0.0000 ;
-0.0000 0.0000 0.0000 -0.0000 0.6579 0.0000 ;
-0.0000 0.0000 0.0000 -0.0000 0.0000 -0.5359 ;
];

V' =
[
-0.3594 -0.4158 -0.4449 -0.4449 -0.4158 -0.3594 ;
0.5577 0.4082 0.1494 -0.1494 -0.4083 -0.5577 ;
0.5234 0.0540 -0.4746 -0.4724 0.0563 0.5211 ;
-0.4072 0.4092 0.4065 -0.4100 -0.4073 0.4093 ;
0.3126 -0.5687 0.2796 0.2784 -0.5699 0.3137 ;
-0.1494 0.4082 -0.5577 0.5577 -0.4082 0.1494 ;
];


U B V' =
[
7.0000 6.0000 5.0000 4.0000 3.0000 2.0000 ;
6.0000 7.0000 6.0000 5.0000 4.0000 3.0000 ;
5.0000 6.0000 7.0000 6.0000 5.0000 4.0000 ;
4.0000 5.0000 6.0000 7.0000 6.0000 5.0000 ;
3.0000 4.0000 5.0000 6.0000 7.0000 6.0000 ;
2.0000 3.0000 4.0000 5.0000 6.0000 7.0000 ;
];
U and V' are unitary.


Working on making SVD converge as fast as possible and to minimize storage requirements. Right now, it holds a whole copy of the tridiagonal matrix B. Storing a lot of elements known to be zero is a bit wasteful, if you believe that information theory voodoo.

Yes, I realize the output B is not *quite* diagonal, but that's with four iterations of the diagonalization process (two Givens rotations per row) and no explicit zeroing of elements.

Problems to solve:
* minimize storage requirements for B.
* figure out whether it is possible to store U and V in factored Householder forms and accumulate the Givens rotations some other way (as opposed to forming U and V explicitly then rotating them to diagonalize as I do now).
* complex Householder reflections

Thursday, July 17, 2008

Singular Venereal Disease

Implemented singular value decomposition in a sense. It's not integrated into VSIPL but rather written as a VSIPL application. That'll change in the next few days.

As the reference implementation of VSIPL lacks this functionality, I'm told I can submit mine to VSIPL forum for distribution perhaps. That'd be a feather in my cap.

My HPEC presentation is taking shape. I have to cover a slide a minute as it is. Probably should condense it.

Emma's here. No more time for interwebs!

Monday, July 14, 2008

Weather Models

Frequently, news articles covering global warming cite weather models that predict the Earth's climate will warm in the coming decades. The articles never mention whether said models have accurately predicted past meteorological trends given historical data. Sometimes articles explicitly claim the models have not. In all cases, the expectation for a model to explain the past is categorically ignored.

I'd like to propose what appears to be an equally valid weather model:


printf("Earth's climate will be hotter 100 years from now.\n");


This clearly achieves the modern standard of rigor for getting the model published. It was cheap to develop, and as a bonus, it accurately confirms what we already know about the future of our planet!

Surely you don't disagree with overwhelming popular opinion on the subject...

DC Exploration

On Thursday, I attempted to visit the Whitehouse to conduct a self-guided tour. On the Metro, I began to sweat profusely and feel light-headed. By the time I approached McPhereson Square, bloodflow to my brain apparently decreased so much that my vision became impaired. I willed myself to remain upright, and when the doors opened I walked forward and groped around for a railing on the platform. I was completely blind by then. Bad news. I'm okay now though.

I need to transmit my medical care facility doctor's note to the person who arranged my tour so they don't think I'm a slacker who failed to show up because I don't value free things.

--

My parents and sister arrived later that evening. We ate Chinese down the street and planned our weekend. I had to work Friday, so they visited Smithsonian museums of their choice. We went to eat at Nathans in Georgetown again which ruled. Saturday, my dad and I drove out to Dulles to see the Steven Udvar-Hazy Center. This is perhaps the greatest single aviation exhibit I've ever seen, and I will gladly take any readers who visit and be just as thrilled to go a second time.

I have photos, but they require post-processing and downsampling. I'll try to get them up soon. I'm creating a flickr account. A separate post will chronicle what was seen with perhaps a way to prevent the strong-willed reader from avoiding spoilers.

Saturday night we ate at The Front Page in Ballston then drove down to the Iwo Jima Memorial after supper. This proved a wise choice as it was low key, parking was free, and the view was splendid. The Netherlands presented the US with a carillon tower in 1960 as a way of demonstrating gratitude for liberating them from the Nazis during 1944-45. A player comes Saturdays from 6pm-8pm and plays. With the gates unlocked, my sister ran up the stairs to obtain a 100ft higher view of Arlington National Cemetery, the Potomac, and the Mall across the river. Next week, I plan to drag Emma along closer to 6pm such that there is more light and take photographs.

Sunday, we returned to the National Gallery and I saw the only Da Vinci work in the United States: Ginevra de Benci. It is painted on both faces of a wooden panel and is mounted in a free-standing exhibit so you can see the reverse as well as the obverse. Ginepro is apparently the Latin term for juniper tree and was used to symbolize chastity. Now we see it as a precursor to gin.

With that, they left Sunday afternoon to split the trip in half. We ate well, and everyone seemed to have a splendid time.

Wednesday, July 9, 2008

Hype v Economics

Scary


The element gallium is in very short supply and the world may well run out of it in just a few years. Indium is threatened too, says Armin Reller, a materials chemist at Germany’s University of Augsburg. He estimates that our planet’s stock of indium will last no more than another decade.



Not so scary
[ArsTechnica]


One of the arguments trotted out in most posts focuses on the fact that the price of Indium has risen from around $95 in 2002 to over $1000 in 2006. What these posts fail to point out is that it was around $180 in 2000, so $95 appears to have been carefully chosen as a starting point. The end point is pretty suspicious as well, given that Indium's price was around $665 in May. Meanwhile, everyone fails to point out that the price of Gallium has remained flat in recent years.

To understand why the supply side has not increased production substantially with this increase in price, you have to look at how Indium is produced. Indium is extracted from raw materials mainly as a by-product of Zinc production. Because the price of Zinc has not increased recently, and may decrease in the near future, producers have little incentive to increase output.


Let's try to keep our heads, Internet.

July 4th Celebrations

Part 1 of my July 4th plans included grilling. The day was sunny, clear, and cool. My roommate Carter and I proceeded to skewer a number of chunks of beef and chicken. We included slices of onion, peppers, and zucchini. With kabobs constructed, I attempted to get a fire roaring on our kettle grill. Rather than rest the fuel on a grate above air vents at the lowest point and rely on convection to produce a flow of oxygen, our grill is simply a large pan. Given the dimensions of the fire I attempted, the result was an anemic heat that demanded approximately 45-60 minutes to grill each kabob.

The result may have been worth it. Each cut was tender and juicy. All those involved concluded the grilling was a success.



Still, air holes will be nice.

--

I spent the rest of the day at home. Some of that time was spent coding. When it was time for fireworks, I remained indoors due to rain.

I spent Saturday indoors as well, though I went out for a midafternoon pedal down the bike paths of Arlington. A rather interesting rail follows I66 all the way to the Key bridge from George Mason Dr (my stoop, practically). Atlanta is missing out.

Thursday, July 3, 2008

July 4

[from Declaration of Independence]


We, therefore, the Representatives of the united States of America, in General Congress, Assembled, appealing to the Supreme Judge of the world for the rectitude of our intentions, do, in the Name, and by Authority of the good People of these Colonies, solemnly publish and declare, That these United Colonies are, and of Right ought to be Free and Independent States; that they are Absolved from all Allegiance to the British Crown, and that all political connection between them and the State of Great Britain, is and ought to be totally dissolved; and that as Free and Independent States, they have full Power to levy War, conclude Peace, contract Alliances, establish Commerce, and to do all other Acts and Things which Independent States may of right do. And for the support of this Declaration, with a firm reliance on the protection of divine Providence, we mutually pledge to each other our Lives, our Fortunes and our sacred Honor.


Respect the gangsta

I shall observe this glorious occasion with kebobs and dry ice.

Monday, June 30, 2008

Nightlife

Saturday night, my friend Nick Merryman graciously invited me to hang out with him, his fiancee, and their friends. This resulted in eating Mediterranean food, drinking tequila from several establishments, dancing in a nearly vacant underground disco, and smoking a hookah. I sneakily managed to hold a pull for the duration of a hookah cycle and exhaled just as the last person exhaled; this made for some surprises. Nick managed to handwhistle with smoke which was pretty amusing.

I need to figure out how to smuggle a portable whiteboard into bars. It would make discussions easier, and we wouldn't have to busily scribble illustrative plots onto napkins.

Nick reported he just sent a PCB out for fabrication which is pretty impressive. I've never done any *real* RF circuit design and consider that to be fairly hardcore. His board, among other things, has pinouts for a 320-pin FPGA.

--

I also need to arrange a rotisserie over a woodgrill in our backyard. My roommate seems to have cooking inclinations, so one weekend we should roast a large pile of meat.

--

On the GPU front, I got TRAC installed and am using it now. Someone at GTRI is using GPU VSIPL which is interesting.

Thursday, June 26, 2008

DC v Heller

DC v Heller


Held:

1. The Second Amendment protects an individual right to possess a firearm unconnected with service in a militia, and to use that arm for traditionally lawful purposes, such as self-defense within the home.
Pp. 2–53.

(a) The Amendment’s prefatory clause announces a purpose, but does not limit or expand the scope of the second part, the operative clause. The operative clause’s text and history demonstrate that it connotes an individual right to keep and bear arms. Pp. 2–22.


Well done.

Update (June 30)

I was going to put this in the comments but I figure it's better if more public.

What firearms can you register in DC now?

Semiautomatic handguns are not registered

No weapon can shoot more
than one shot by a single function of the trigger,
or semi-automatically shoot more than 12 shots
without manual reloading or be readily converted
or restored to do so.


I mention this just so people realize that Heller only labels broad and general bans as unconstitutional. Neither the courts nor legislatures have received much guidance by this decision to determine what other types of restrictions might also be unconstitutional. Clearly, it helps to establish the individual right to keep and bear arms and to clarify the self-defense purpose inherent in the 2nd Amendment. It is also helpful to state that "handguns" cannot be prohibited.

It has been observed that the ruling was close. This matters to an extent, but I don't think the narrow outcome is going to be the most significant source of legal activity to follow, at least in the next few years. District v Heller acknowledges the validity of some restrictions and does not go into detail about what those might be limited to. The laws are in a flux now, and both sides see plenty of opportunity to go forward.

With regard to "no semiautomatics," the 'readily converted or restored to' clause covers any weapon for which a >12 round magazine exists by my interpretation. You can buy a 45 round drum for 1911s on GunBroker for $60 or so. Everyone but Nic recognizes the world of difference between semiautomatics and manually fed weapons. This new kind of ban is going to be the new language and style of the debate.

Amusingly, it is not contradictory to support the Heller decision and yet defend the semiautomatic ban. Watch for that from both presidential candidates as they can easily appear to appease both sides. Terms like "common sense" will fly out of mouths as effortlessly as hot air.

Tuesday, June 24, 2008

Condition 1

While simulating, I read a short piece on 'condition one' carrying of a 1911. I didn't exactly learn anything I didn't already agree with. In fact, at the end, the author suggested an experiment I've already performed to relieve my own anguish.

To get over whatever fears you may have of carrying a 1911 in condition one, cock and lock it with an empty chamber and carry as you normally do. When undressing and disarming, take note for yourself the position of the hammer and see that the weapon does not in fact fire itself. Repeat until you're finally brave enough to rack one in as it were before holstering.

You have been carrying, right?

Survival Instinct


If [the levee outside St. Charles, MO] breaches, the river will swamp 100 homes in east Winfield, as well as 3,000 acres of farm fields, several businesses and a city ballpark. A muskrat that burrowed a hole in the soft ground released a geyser of water, and officials said it took nearly six hours Monday to choke off the leak.


Bastard muskrats. With the nearby water table literally above your head, you shouldn't make holes in the ground no matter your species.

Monday, June 23, 2008

Talking to the Police

The reader(s) of this blog tend to tread the same grounds, but I thought I'd point out that I finally watched

Talking with the Police

It's pretty amusing and paints an idyllic portrait of law school. Prof. James Duane cites eight good reasons why talking to the police has no upside and plenty of downside.

8.) No matter how careful you are, even if you're completely innocent and do not implicate yourself in any way, the mere act of making a statement opens yourself up to problems if someone else bears false witness against you (perhaps by mistake and police later convince them their vague feeling is in fact a solid recollection). That's bad.

That said, in November 2006 I was more or less suspected of fraud. Someone (not me) used my name and whatever information that is available about me in the Real White Pages to make an online purchase with a stolen credit card. I agreed to help the police and by the end of the interview was permitted to use the investigating officer's computer for research to save everyone time.

I haven't heard about it since, but I wonder what direction he would have taken the investigation had I refused to say anything... as I understand it, search warrants aren't all that challenging to get if you ask the right court. That alone would have been a major pain in the ass to have my computer seized shortly before Deadweek.

Did performing the opposite of Prof. Duane's advice save me some trouble? His lecture suggests that the only reason things went as well for me as they did is because the officer didn't think I was responsible to begin with. "Have you ever had your mind changed by talking to a suspect, Officer Invited Guest? No?"

Comments or analysis?

South Carolina, Georgia Reciprocity

The South Carolina House recently approved a bill establishing reciprocity for CCW permits issued by other states.

Alive

I'm alive. My phone has been in quiet-and-ignored mode since Emma got here, and my laptop has been off. This was meant to be no slight to anyone. I simply wanted to prioritize my focus, and it was refreshing. I'll start returning calls and texts during my lunchbreak today.

We ate at El Ranchero, an Italian restaurant, Nathans (in Georgetown), P.F. Changs, and Andy's Bed and Breakfast. These are places in which dining alone would be somewhat awkward, but with Emma they couldn't have been better.

Emma seemed to get a kick out of Georgetown. It's a scenic area with plenty of interesting shops and well-dressed and exciting passers by. We stopped in at a few and thoroughly soaked up the atmosphere. Since we drove, we took an evening motor tour of the District passing by the Whitehouse, the Supreme Court, the Capitol, a brief and not necessarily planned excursion by the FDR Memorial, the Pentagon, the Air Force Memorial, and an inventive detour through west Arlington.

Then we drank whiskey that we finally managed to procure from the state-run Alcohol Beverage Control stores. It is located half a block from my workplace and closes early, so I prognosticate some lunchbreak liquor runs when I run low in the coming months; I can only hope I run into my colleagues while I'm there.

During our visit to the National Mall, we managed to cover the Hirshhorn Museum of Modern Art and then the National Gallery. We saw a variety of cool pieces at the Hirshhorn though were occasionally faced with the typical dilemma of modern art appreciation: are you looking at a work of art or a fire code regulation? We made sort of a whirlwind tour of the National Gallery seeing several rather old busts of important people (Washing-ton, for example) and a few positively grand paintings (Lake Lucerne being my favorite).

The Spy Museum and the Newseum are planned for the next trip.

Emma has photos, and she left me her pink point-and-shoot camera (the one that has incriminated so many of us on Facebook). I'll take higher resolution photos from now on.

It was a fun visit and I can't wait to fly her back here sometime soon. Now that she's back in ATL, your lives can go back to being interesting again.

Heh. You know you like abuse, gentle reader.

Thursday, June 19, 2008

Bright Side

The heartwrenching Flood '08 disaster is still on-going, but I just received a bit of good news.

Both abstracts were accepted by the HPEC Workshop. This would be a good thing, only they're both talks instead of posters, and one is in the awards session. Moreover, there's only the month of August to plan the talks and prepare. I feel like Faust somehow, though I don't remember signing anything.

But enough about the world's events: Emma's coming to town!

Wednesday, June 18, 2008

Directly Hit

Here's an aerial shot of the levee breach. That's the farm right there, and the water currents are intense. The machine shop doesn't even appear to be there producing a wake. Formerly, it was just south of the west (left) silo. This is unreal.





Update

There is a video of the "South Indian Grave Levee" here. I was trying to figure out the velocity of the water at the surface to determine how much force due to dynamic pressure of the water the barn was withstanding. I'm estimating about 3 m/s.

Apparently yesterday morning, the barn collapsed and the debris washed away. It's like turning a firehose onto a model railroad. The only structure remaining is the house my mom grew up in, cleverly located on the top of a small man-made hill in the cluster of trees north of the tall silo.

Unfortunately, the cleanup effort will involve removing hundreds of tons of sand so the soil next to the levee breach can be farmed again.

Tuesday, June 17, 2008

Rivers and Farms

My grandparents operate a 426 acre farm along the Mississippi River north of the town of Quincy. I've loved going there and my earliest and fondest memories are at the farm visiting Annie and Duke (grandparents). For someone who likes to build things and see how things work, farms are great. The machine shop is full of welders, lathes, machinery, large engines in various states of disassembly. Tractors and interesting work abounds.

Uniquely Joe and I would like access to a farm for a variety of reasons. My grandfather tells a story about a time an ultralight pilot landed in one of his fields. After Duke welded a strut affiliated with the planes landing gear, the guy took off again. UAV research would be pretty much unobstructed.

Here is a Google Maps view of the farm.

In 1993, the levees broke up and down the river. You can see the foundations of several buildings on the farm demolished during that flood on Google Maps.

It's late June, and the river is up again. Visit this plot of the observed and predicted River stage for the next few days.

The river stage is predicted to crest slightly higher than the record, which occurred the day after the levees broke in that area during the 1993 flood.

Let's hope they're stronger now.

If they don't get any rain, they might just last.

Update



The district Indian Grave is the one. Looks like flooding is happening although it's not clear where.

Update

The whole district is flooded. The levees weren't high enough and water flowed over the top quickly eroding the rest and flooding the entire area. It's going to be a while before the flood waters recede. The rather neat barn and shop will be subjected to windstorms and floating debris (trees, houses, etc). Hopefully, they'll withstand the torrents well enough. They're really priceless structures I'd rather be able to see and visit. I think my sister has a few photos on Facebook.

This barn is visible in the upper right corner in the background of this image:


The shed I built last summer when I was there was recently seen floating north, away from the farm. I wouldn't call it priceless, but it'd be nice if they could retrieve it eventually.

Sunday, June 15, 2008

Range Report

I took the new .308 to the 50 yard indoor range at the NRA headquarters in Fairfax. Their range includes an automated target positioning system letting the user select a range for their target via a keypad. A button press places the target, recalls the target, and then replaces it at the last entered range. This is useful because you can devote your attention to other things while the target is headed out like loading the next magazine or cleaning. This also facilitates close inspections of each group before the next is fired. Without feedback and an honest assessment of achieved performance, it's rather difficult to improve.

I ran a dry patch through the bore between every two rounds for the first 20 to perform barrel "break-in." No solvents were permitted on the range.

The weapon was fairly easy to zero requiring only windage adjustments. My two- and three- shot groups landed within 4cm circles which is encouraging. I surely need to practice with this trigger a bit. There is in fact some slack that needs to be taken up that I didn't really notice earlier. Things to eventually buy: a bipod I can mount to the rails, optics.

I fired several rounds from a standing position with the sling. It's fairly natural, though the ribbed quad-rail handguard can be rough on hands. Operators wear gloves, and I probably should too. In 35 rounds, the bore never got particularly dirty. There were no failures to speak of by the rifle system, though presumably reliability problems by direct-impingement gas systems aren't likely to surface in fewer than several hundred dirty rounds fired on the field of battle. Recoil is what you would expect from a .308: neither punishing nor ignorable.

I didn't do any 1911 work though probably should have. Though I spent the whole hour on the rifle, they didn't seem too concerned with time on the range.

Post shooting, I bought some CLP and deposited the rifle in the vehicle. The NRA has a museum featuring a variety of arms from the last three hundred years or so. I paid particular attention to the M14s, Garands, and M1903s on display. I discovered a 1911 with a scope [mounted to a riser bolted to the left side of the recevier; couldn't see how that interfered with the safety or mag release]. Charles Manson's shotgun was on display as well as a "zip gun manufactured in a prison cell."

Some gentlemen were walking and talking. Their discussion was the M14/M16 debate, so naturally I piped up. With regard to calibers, I commented that the 6.5 Grendel has the potential to answer the intermediate rifle cartridge question if only the obstacles were strictly engineering.

Other notable arms on display:
* M24 SWS
* M40A1
* SVD Dragunov
* MG42 mock-up
* M82 Barret .50

No crew-fed weapons were apparently on display, so I didn't see any M2s. They did a decent job covering the relationship between firearms and the defense of liberty, though presumably any mention of that topic is preaching to an attentive choir.

And now, I nap. It's been a good day.

Friday, June 6, 2008

Rollin', Rollin', Rollin'

Acquired a book on rotations and quaternions. At last, the parametric ball will be mine to toy with, bitches. Expect some kind of demo to come of this.

Thursday, June 5, 2008

Happy Birthday, Sara

Happy Birthday, Sara! Need birthday blog posts. Sorry everyone went out of town just in time for it.

Sprezzatura

You would probably like to know this word.

Sprezzatura: a certain nonchalance, so as to conceal all art and make whatever one does or says appear to be without effort and almost without any thought about it

Whether this involves being an asshole about it is a decision left to the courtier.

Working in the Dark

I'm using slides as a primary resource to assemble my own presentation. Reading the slides has raised questions, and I have no direct way of answering them. I'm beginning to detect the faint aroma of Engineering by PowerPoint.

--

comp.lang.c++ occasionally poses C++ questions I haven't been able to answer. This is concerning.

I suppose I consciously avoid facing some of these issues by my design and development style. I cite this phenomenon as the big reason why C++ amateurs stay amateurs and don't necessarily realize it. That said, I've never worked on a "big" C++ project that required things like overriding new and delete operators, passing custom allocators to STL objects, or doing anything that really required virtual base classes and multiple inheritance. Having never faced those issues, I haven't been exposed to the sort of deep and nuanced language and implementation issues, and haven't received the educational benefit of trying to solve them.

--

I want to setup an installation of TRAC or some similar bug tracking resource. It'd be a good way to organize thoughts and fix other people's bugs. Ahem.

--

Whatever happened to Linkwell?

Inappropriate at Any Speed

AndyKerr on academic compilers during today's project-wide meeting:

"That depends on how pluggable their backends are . . . so to speak."

In other news, Shooter's sound effects were totally better than The Bourne Supremacy's. I don't know how the Academy passed it over.

Wednesday, June 4, 2008

Newsgroup fun

From comp.lang.c:


> Why should it? There is no requirement anywhere
> (afaik) to have a fully comforting compiler.

Even though it's only May, I'm already putting that in the running for Best Typo of the Year.


No requirement at all.

Monday, June 2, 2008

Random DC Photos

Here is a selection of images taken with my 640x480 camera phone since my arrival. I apologize for their quality. I didn't spend a lot of time formatting things, so you may have to right-click on each image and select 'View Image' to get the right most columns of pixels.


My house.


My desk.


Steps of the Jefferson Memorial.


Jefferson himself. He owns joo metaphorically, and, in the case of his slaves, quite literally.


My glorious steed parked near the steps of the Capitol. Together, we are like one, impatient spirit.


The Capitol, workplace of our country's most collectively despised and yet honored citizens.


The Supreme Court. Chief Justice Roberts was clearly not in the house this day, for it is not overflowing with dancing hoes and playas eager to sip Tanqueray with the man.


Pro-life douches. Some might say it's noble and brave that they're standing up for what they believe. To these I say that no one gets commendation for being a strong-willed dumbass. To earn praise, you also have to be right. If these assholes really wanted to reduce the number of abortions that took place in this country, they'd be lobbying for subsidized birth control and sex education that acknowledges the possibility of sex. Assholes. Oh man.


A Lunar Module in the National Air & Space Museum. This is a genuine flight article that would have been flown on one of the later Apollo lunar missions. These missions were canceled to save money and a Saturn V to launch Skylab.


This is the camera from Surveyor 3. Surveyor 3 was an unmanned spacecraft that landed softly on the Ocean of Storms (a lava flow on the Moon) in 1967. It took photographs and scraped the surface with a retractable robotic arm (not unlike Mars Phoenix is doing now a bit further from Earth). In 1969, the crew of Apollo 12 landed several hundred yards away, approached it, took photographs of the occasion, and removed the camera mounted on the top surface of the lander. It now sits on display in the Air&Space Museum facing ugly tourists instead of an incredible panorama of Surveyor Crater on the surface of the Moon.


Iwo Jima Memorial. This is on my route to the Memorial Bridge between downtown Arlington and Arlington National Cemetery, so I get to see it a lot. I always stop to gaze for a minute. It's a pretty powerful monument and something large and imposing to live up to.

--

There are additional images in this directory that I didn't believe my captions could do justice. Four photos contain the text on the walls of the Jefferson Memorial which you can read and obtain context from the wikipedia article.

--


Update

Inside of the original propeller spinner for the Spirit of St. Louis. The first part of Lindbergh's flight was to fly from San Diego, California, to Long Island, New York. From there he would fly to Le Borget Field in Paris. When he landed in Long Island, cracks in the propeller spinner (above) were discovered, and a new one was quickly manufactured. Since this one was intended to fly across the Atlantic Ocean, people involved with the project [construction of the plane, fund raising, flight planning, etc] signed their names to the inside. The swastika in the center surely receives much attention, but in fact it has no relation to the Nazi emblem. It's simply a symbol that has been around for thousands of years meant to convey good luck. This version differs from what later became the official Nazi insignia in two distinct ways: it is not rotated 45 degrees, and the arms of the swastika are oriented in the opposite direction. Clearly, I took a photo of it anyway because everyone loves the hint of a good scandal.
/Update

Saturday, May 31, 2008

Resume Spam

I received spam from someone in Russia containing their resume. Wtf. Can someone explain this?


Fifteen years of experience with C++ programming, including nine years with
Visual C++ and MFC and 5 years with COM/ATL/WTL/ActiveX and IRC, POP3, SMTP,
MIME, IMAP protocols. One year of experience with C# programming, .net and ATL Server web developing. Developed skills in the utilization of ODBC and OLE DB
to access databases of different types, particularly ORACLE, DB2 and
MS Access. Knowledge of SQL, ActiveX. ...

4! Years

My new age.

--

Update

The El Ranchero bar tender told me to "slow down" after I finished shot number two of Petron before receiving the first bowl of chips (initial offset was one bottle of "Liberty Ale"). By the time I switched to Sambuca he learned his lesson and recognized me for the accomplished drinker I appeared to be.

As they were closing, one of the other bartenders broke out with Roxette's "She's got the look" to which I sang along. You'll like this place.

Friday, May 30, 2008

Working for Weekend, Man

I'm low on ideas for getting VSIPL Lite + Integer functions to run any faster. The plan I was investigating was hoped to mitigate the inefficient memory accesses you face when accessing vectors with nonunit stride [i.e. consecutive elements in a vector are not consecutive in memory].

--

I'm investigating several parallel programming languages, "paper languages" as they have been called due to their lack of substantial toolchain support and only significant utility being you can write papers about them. They all begin with well-constructed preambles regarding the woeful state of affairs in the parallel programming community in which only a single style of parallelism is well-represented by a particular language or solution. OpenMP, for instance, is really only suitable for data-level parallelism on a shared memory machine. MPI is suitable for task-level parallelism on a cluster. Neither one satisfies both domains well if even at all. The ones I've encountered so far (StreamIt, Brook, Chapel) sound reasonable. But claims of productivity need to be backed up, so we're all going to implement useful things with them and then compare notes.

Here is a fairly comprehensive list of languages that capture the sentiment. Some of them you wouldn't actually want to use in general. Some are domain specific (SystemC being the interesting one of those I think), and others are narrowly-scoped extensions of an existing paradigm (Intel SSE, for example, are SIMD instructions added to x86 - useful, but you'll probably never touch them yourself).

Parallel Languages

I'm going to try to implement FFT using StreamIt, Unified Parallel C (UPC), and perhaps Brook or some other streaming language in the next few days.

--

I am now the proud owner of a GeForce 9800 GX2. Help me think of things to do with it besides use it as an alternative to central heating.

TSMC plays fast and loose with process design rules so overclockability may be limited, though I'm still inclined to try. I didn't with the GF8800GTX because I needed an easily-reproduced platform on which to perform benchmarks. One interesting aspect of the GX2 card is that while it has a total of 1GB of video memory, they are partitioned into two address spaces, each accessible by one GPU. Each device can only allocate <512MB buffers, and exchanging data among GPUs is fairly slow [via the SLI]. Nevertheless, task-level parallelism and pipelining ought to perform well.

--

Grand purchase will be delayed one more week but no longer. This has strategic goals in mind.

Thursday, May 29, 2008

Dry ice bomb, California Loophole

For the purposes of this discussion, a "dry ice" bomb is a sealed bottle containing dry ice and possibly some other fluid to serve as a heat sink. As the dry ice is warmed, it sublimes producing pressure that eventually ruptures the bottle. The rapidly expanding CO2 initiates a suitable "boom!" greatly amusing those around.

It seems as if the legislature of California attempted to prohibit such devices. Section 12301.a.6.


12301. (a) The term "destructive device," as used in this chapter, shall include any of the following weapons:
...
(6) Any sealed device containing dry ice (CO2) or other chemically reactive substances assembled for the purpose of causing an explosion by a chemical reaction.


Yet, I fail to see how this could possibly cover "dry ice bomb" as I've defined it above and as many have practiced it. The mechanical explosion from the ruptured bottle is not due to a chemical reaction of any sort. The CO2 is still CO2, just in a different phase.

Either I'm misreading their intent, or some legislators missed the mark.

Tuesday, May 27, 2008

Memorial Day

Performed another bike tour through the District. This time, I crossed via the Key bridge, so named for Francis Scott Key whose residence is near the north end of the bridge. The Georgetown area is rather splendid and certainly the place to go to have a good time.

I headed directly for the Jefferson Memorial further south. I was not the only person there, though it was surprisingly vacant. Numerous peddelboats tread the waters of the Tidal Basin over which the Jefferson Memorial looks. I locked up the bike, headed up the steps, and looked around. Four blocks of text, distinct excerpts from his writing, adorn the walls surrounding a large statue of the man. Read them from the Wikipedia article. I'll wait.

After digesting them, I tried to imagine Jefferson meshing with some of the political movements that have taken place since. Several (Prohibition, Drug War, Copyright Gestapo) are irreconcilable. I wonder of modern law makers ever stop to wonder whether their ideas are consonant with the principles of one of the most significant and beneficial philosophical influences this country has ever known. Does it worry them when they are not?

Returned to the mall, did a lap around the Capitol, and passed the Supreme Court. This time I climbed the steps, bike in hands, and walked up to the doors.

I decided that the crowds were sufficiently sparse that I could visit a museum of my choice if I desired. I parked outside Air and Space, concealed my knife in my bike water bottle, and went inside. I made a rather swift tour focusing mainly on spaceflight. The TV camera from Surveyor 3 was on display. Seeing it brought me satisfaction.

Returned, showered, napped, grilled, and watched Andromeda Strain. Those were probably two hours of the most epic death sequences ever televised. The Story of Ricky O has got nothing.

Now, sleep. Work again tomorrow.

Sunday, May 25, 2008

Pirates and Firearrrms

Check out this pirate's M-14. He's not messing around.

Also, check out this thread I started on The Box O Truth's Discussion forums a while ago. I won't repost the thread, but the general idea is:

* do you have knowledge of an actual defense system employed on a nonmilitary vessel?
* what would you choose for defenses yourself? [constrained that the weapons ought not cost more than the vessel]

Post in the comments.

Saturday, May 24, 2008

PhysX and DirectX



PhysX is officially the thing to use for in-game realtime physics unless you want to duplicate that functionality for fun. I wish the CUDA implementation were available so I could feel comfortable with thousands of objects in one scene. I'll see about compiling this for Windows XP sometime soon.

DC Metro Fiasco

The efficiency and accessibility of the DC Metro to riders with bicycles has been vastly overstated. Friday, I had planned to meet a friend at the National Mall during my extended lunch break. Instead, I spent over five critical minutes trapped in an elevator on the train platform at the Ballston station and missed a train thus delaying me by about thirty minutes. I encountered more broken elevators at Metro Center where I decided to disembark delaying me further. The lack of any other cyclists on the train confirmed what I've already come to believe: that bicycles on the metro are a mistake and you shouldn't attempt it ever. After arriving at the Mall, I biked back to work passing the National Cemetery on my way.

--

Work is enjoyable. I've accumulated one gold star so far. I'm eager to get results and finish the VSIPL implementation they want ported. After that, we start investigating methods for application development and, potentially, compiler research though that's typically not the best level of abstraction to perform crucial restructuring for parallelism unless you modify the programming language as well (with CUDA, Cell SPE intrinsics, and Fortran as examples).

--

PhysX is pretty straightforward with a sensible class hierarchy and all of the objects you would expect: a generic scene, a generic shape, effectors, linear spring and damper systems, force fields, triggers, convex meshes, ray tests, etc. Coprocessors are supported by encapsulating objects in non-user space and providing explicit means for transferring object state back to user space.

Achieving a fast platform-independent [PC, PS3, Xbox360, GPU soon] implementation is something NVIDIA hasn't published yet, but I'm really interested in seeing about that when the time comes. They may not open source it for a while though.

--

Plan for Monday [Visiting Research Assistants are not hourly, and we all have Monday off]: get up at reasonable hour, bike through the district, and have supper at the Quarter Deck, a seafood restaurant near the river. I'm determined to develop tastes in seafood having largely shunned it up to this point.

--

I'd rank El Ranchero in my top three Mexican restaurants of all time.

Friday, May 23, 2008

_mm_prefetch

I finally met the roommate who lives downstairs. He's building a UI framework in Javascript for Network Solutions. He reminds me of Sebastian Bach. We drank [gin from the Erlenmeyer flask], played the Wii last night, and carried on.

--

Arlington is a splendid little city of a town with a precious business district with its eight-story skyscrapers and sky bridge. This place is relaxed and hardly fast-paced at all. You will like it when you visit, gentle reader. Every commute is a pleasure whether on foot, bike, or car [drove today].

--

Josh pointed me toward github. Since git is apparently the new hotness, I suppose I'd better get a move on. That said, a workplace I'm familiar with is moving from CVS to Subversion tomorrow.

--

I download NVIDIA's PhysX SDK [binary only right now, still has the styling of a non-NVIDIA SDK] and plan to mess around with it over the weekend. Eventually, they'll finish their CUDA PhysX implementation, and the darling CUDA-enabled GPU in this laptop will takeover the lion's share of processing. The ballpit will live.

--

My birthday is a week from Saturday. I think I may make a grand purchase for myself that day.

--

Leave comments, tell your friends to update links. Love.

Tuesday, May 20, 2008

Public Misunderstanding of Mathematics and Pedagogy

Waisting time because I'm stuck.

From Fark: Failure from 0 to 50.

"It's a classic mathematical dilemma: that the students have a six times greater chance of getting an F," says Douglas Reeves.


Dumbass.

His retarded probability estimate defies belief. This isn't how tolerances work.

I can't imagine anyone saying something as stupid if they were talking about parts from an assembly line. For example, if the tolerance of a resistor is +-5% from some factory, claiming "resistors have a nine times greater chance of being discarded [than being shipped] on the basis that 100% - 2*5% = 90%, and 90% / (2*5%) = 9" is utterly asinine. The quantity 90% is meaningless and says nothing about the underlying probability distribution.

Goddamn. This is stupid.

Free academic credit awarded to encourage self-esteem in spite of sucking at school is also a bad idea, but the douchebags mentioned in this article disqualify their own opinions long before we can even approach the topics of psychology and education.

That said, you know what might help students to feel better about themselves? Being able to get right answers on their own.

Second Day

Much of the technical information regarding the project I'm working on is covered by an NDA, so I'll probably be avoiding it as blogtopics go.

Instead, I give you this: biking through the city at a pace that keeps up with cars is kind of dangerous, but it's also kind of fun. There's a lot going on to be aware of, and pumping really hard in top gear from a standing stop so you accelerate with traffic can be exhausting, but the thrill of it all grows with each stroke. It's a great way to start a work day.

--

There were several shootings in DC in the last day. None in Arlington. Guns that are in a condition from which they may be fired are illegal in DC, so I suppose the fundamental flaws of gun prohibitions have tragically surfaced again. I'm going to try to be on the Courthouse steps the day the decision of Heller vs DC comes out [if I can].

Monday, May 19, 2008

ISI East: First Day

It's the first day here at ISI East. This office occupies the second floor of a building in downtown Arlington which is so near my home that the commute is hardly even a workout, which is what you want, I suppose. It took me eight minutes from helmet donning to helmet doffing in the deck. I have my own room with two whiteboards, a bookshelf, and line of sight to a partially occluded window in the office across the hall [all things more marvelous than the CRB]. The people here seem friendly, though diving right in has been difficult since all of the technical information is held by people who aren't ready to meet with me yet.

While I wait for a meeting occupying my new supervisors to end, I'm familiarizing myself with Python 3000. All of the old Python cruft has been removed. This wasn't by anyone's recommendation, but my first day at GTRI also began with Python so it's somewhat appropriate. I suppose I'll have to get a new job with the release of each major version of Python (SBIR by Python 3.5??).

--

In other news, I shared the magic that is Guinness Beer Stew with one of the roommates. I still haven't met the owner of the Wii I've been playing.

--

I like Blogger, incidentally. This may become my official permanent blog, so in the mean time you should direct yourself and any other readers here and update your links.

Sunday, May 18, 2008

VSIPL and Beer Stew

On St. Patrick's Day, I made a pot Guiness Beer Stew and ate on it for the next three days or so. The beer stew I'm making now is going to compose lunches and tonight's supper for the next few days. Cooking is only economical if done in large batches, and the ability to consume left-overs is an essential skill. An hour of preparation and $12.00 on day zero yield meals spanning the next three days.

So, I'm adjusting rather well to this area. The environs are aesthetically gratifying, and there's no shortage of human activity to counter the feelings of isolation that set in when the people you know are scattered hundreds of miles away. As advertised, this house has a Wii which will surely result in much time wasted.

GPU VSIPL development on Windows Vista is dramatic. I've kernel-panic-ed my laptop several times so far. The GPU onboard has about 1/10th the theoretical performance of my desktop, but it's still worthwhile. I can do performance benchmarking via SSH-tunneled-VNC to a machine at CCRF.

Work starts tomorrow. I'm very enthused about it and only slightly nervous about starting.

--
P.S.

Yesterday's five hour bike tour through DC and Arlington has resulted in soreness in two areas: my elbows, and my crotch. When speeding up and slowing down [good brakes mean you can go faster, it's true], your arms apply nearly all tangent forces to your torso. Any time you brake, your arms bear much of the load. That can be exhausting and intense on the elbows. Your crotch provides all normal forces to your body, and after a few hours begins to complain about it. I wasn't quite expecting my legs to be so comfortable with the workout.

Freedom

The Statue of Freedom atop the US Capitol has a sword in her hand, presumably because liberty is something you must be prepared to take if necessary.

Saturday, May 17, 2008

Biking through Washington, Washington

This is my second full day in the new dwelling. I woke up around 10:00am, made coffee and drank it while reading Bike Arlington. Trails lead me from my front door to the Iwo Jima memorial, the Neatherlands carillon, and along Arlington Cemetery to the Memorial Bridge.

After checking tire pressure and filling my water bottle, I set out. In no less than five minutes, I became exceedingly tired just as I was passing my new workplace. I even began to grow light-headed. Feeling a little ridiculous, I pressed on ignoring the pains and eventually all of the symptoms went away. I was reminded by a statement by Churchill: "When going through Hell, keep going." In no time at all, I was keeping up with traffic along level roads and flying down grades as I raced toward the Iwo Jima Memorial.

The memorial consists of a reproduction of Joseph Rosenthal's epic photograph of men struggling to raise the US Flag on a pole atop a hill of rubble. The details of the M1 Garand and M1 Carbines carried by the men were impressive. Several marines stood by answering questions and mingling with onlookers.

I pressed on and made it to the Neatherlands Carillon given to the US in 1960 as a way of paying tribute for our help liberating them during WWII. From that vantage point, I was directly west of the Lincoln Memorial on the Arlington side of the Potomac River. Because Arlington is somewhat elevated, I had a clear view of much of the Washington Mall. I could see the Capitol in the distance and the Jefferson Memorial off in the distance, not likely to receive my company on this day. It was at this point that Brad Neely's "Washington, Washing-ton" video began playing incessantly in my mind. "Six foot twenty fucking killing for fun..." I sped off across the bridge.

Bike Arlington mentions several rules of biking on sidewalks and in the vicinity of pedestrians. When passing, do so on the left and call out your intention to pass with enough time for them to accommodate you. Pass with at least two feet between them and you. These were sensible enough, and I was eager to play by the rules and mesh cleanly and neatly with this strangely inviting bicycle culture. The Arlington people responded nicely to "passing on the left" and instantly reacted by moving to the right. I said thank you each time, and surely no feathers were ruffled.

On the Washington side, things were different. The Arlington Memorial bridge takes you directly from Arlington Cemetery to the Lincoln Memorial which today was full of tourists. As I approached their flocks, pedestrians either ignored the announcement "passing to the left" in which case I darted around them, or they froze like possums and then started moving in random directions, many of which made things worse. My patience was beginning to diminish, though my skill with handling the bike in crowds without sacrificing much speed was growing. My confidence in doing so grew as well, and I began to label my tour through DC an act of "pedestrian bowling." At one point, I approached a single white male with plenty of room to clear him, so I decided to play a trick as I passed. "Passing on your left AND your right." He just looked around confused as I zipped by. Quantum Cyclist was amused.

My plan for the day was not to visit museums but simply gather intel regarding the arrangement of various sites of opportunity, test the utility of my bicycle, and to enjoy the weather. It's still rather cool and clear here, and today there was a gentle breeze puffing softly to the East [I would later call the same breeze a raging impenetrable squall as I pressed back home this afternoon].

I passed by the Reflecting Pond lined with scores of onlookers, the Washington Monument, and I entered the National Mall. The Air and Space museum was visible from afar as were several other museums. The expansive US Capitol Building dominates the far end of the Mall, so I resolved to see it. But first, I turned north believing the White House to be nearby. I quickly encountered Pennsylvania Avenue and zipped through the obstruction blocking automobiles from passing by. The sidewalk narrowed, and the White House South Lawn came into view. It was rather pretty, and I attempted a few camera phone photographs. For some strange reason, other people taking photographs did so not from against the fence but from the far side of the sidewalk, so while there was space to pass, doing so interrupted their photographs. It was an odd trend. He saves children but not the British children.

I turned North and passed by the US Treasury building stopping for a photo. Coming around again, I passed along the north face of the White House which is much closer and took another photograph. I finally made it back to the Mall and made a beeline toward the Capitol. As I approached, I noticed an arrangement of chairs and and a voice came over a loudspeaker. Apparently George Washington University was practicing their graduation arrangements. Future be ware; he's coming.

I made it up to the Capitol steps and parked. I overheard someone asking police manning a human barricade whether tourists were allowed inside. "No sir. This is the USSR and citizens are not permitted to observe their government in action. Just kidding, you have to be on a guided tour and you can get tickets [nearby]." I reflected on the notion of an open government, and took a photo pridefully. I called Nic who suggested I visit the Courthouse and gave me directions.

Biking around the Capitol, I got a better sense of how large a building it is. The great size surely is intimidating and impressive to arriving dignitaries. Twelve stories tall made of radiation.

Continuing on, I came upon the US Supreme Court building. Nic had asked if there were protesters, but I could only spot one person in the otherwise relatively vacant space of the Courthouse steps involved in a protest. She was at the foot of the stairs with a piece of red tape over her mouth on which the term "pro life" had been written. She stared plaintively at the courthouse but glanced over to me a few times. I figure dropping a pile of bloody wire coat hangers off at "pro life" protesters feet might send a bit of a message, but no one I know has time to be politically active during the week; we all have jobs.

The rest of this block is devoted to House and Senate offices which I paid suitable attention to. Being the weekend, no one ostensibly important was likely to be coming out of them, so I didn't wait too long. I pedaled around to the south edge of the mall and entertained the possibility of visiting at least one of the Smithsonian Museums. It was pointed out to me earlier and reiterated today that the American History Museum was closed for renovations which is rather disappointing. I arrived at the Air&Space and began casting about for a place to put my bike. In doing so, I noticed the lines of eager visitors and decided that I should probably do that a different day so I started out for home.

As I arrived at the Memorial Bridge, this time on the north edge, I came upon a hillside with stairs facing the river. Airliners on approach were flying directly overhead at perhaps less than 2000 ft and mushing along at high angles of attack, low airspeed, and slipping in a cross wind. I decided to rest and watch them for a while.

Emma called me and gave me reports of her 31st story hotel room in downtown Boston in which she'll spend the remainder of her trip [stirring my envy]. We talked for a bit, and as we did a small sailboat with a single sail came into view. A middle aged couple were out sailing in perfect weather with a constant wind blowing across the river meaning you can go north or south with very little effort. Their novice sailing skills became apparent when the wife lost her hat and they attempted to pull up along side to retrieve it. This maneuver is identical to man-overboard drills, so coming close enough to pick up the floating object on the first pass without hitting it with the boat is an important thing for any sailor to be able to do. They made three passes, accidentally gybed a few times [with the consequences on a larger boat that someone might get hit in the head by a fast-moving boom having the force of the wind behind it], and moved under the bridge and out of my view without having retrieved their target. They were having fun though.

I resolved at that point to somehow go sailing in the Potomac at least once, preferably more. This may require buying [or building] a boat if I can't rent one. Hmm. He threw a knife into Heaven and could kill with his stare.

I finally crossed the bridge with the wind in my face, up the hills that I had so effortlessly glided down, and eventually made it back to Fairfax drive and then to my house in Fields Park. It was a delightful day.

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This said, I highly recommend biking through Washington. The city is friendly toward bikes, and if you can handle pedestrians and other cyclists you can get around rather quickly without spending a lot of energy doing so. It's also a lot of fun. A bike rack at Emma's capable of carrying three full-size bikes is available to anyone wanting to come visit.

Here I am exhausted after a rather good day. I'll try to get the camera phone photos up soon.