Neutrons, Knots and Nonimaging Optics

Radiation visualization map

2011-03-25T10:08:00.000-07:00

The Fukushima event has a lot of people worried. Understandable, I am worried for the people in the area of the reactor too, and for the victims of the devastating tsunami and earthquake the has killed thousands. But I was surprised how many people shifted their focus to concern for the United States thinking we were in immediate danger here in California.

I was also surprised how poorly information is being supplied to the public. Many institutions are making measurements but the communication of that data is not clear those few of us who are not nuclear physicists.

So fellow graduate student Riccardo Schmid and I, both at the California Institute of Technology in the Kellogg Radiation Laboratory, decided to make a map that visualizes data generated from the EPA provided RadNet.

The map shows the intensity of radiation relative to the normal levels and is updated hourly.

The area and color of each circle on the map represents the total measured radiation relative to normal levels from each RadNet station. A reading of 1.0x would mean levels of radiation in the air are normal. A reading of 2.0x would indicate that radiation in the air is twice the normal rate, and so on.

Are Knots Related to Fractals?

2010-02-09T16:29:00.000-08:00

Wu and Wang analyze the roots of Jones polynomials for prime knots up to 10 crossings and find an interesting patten emerges on the complex plane which has shadows of the Mandelbrot set.

The roots of the Jones polynomials

The Mandelbrot set

Here is a composite image of the Mandelbrot set and the negative of the Jones polynomial roots which I generated using Mathematica. This is up to 10 crossings and you can see the promising pattern has some serious flaws.

eSolar in the News

2009-02-02T00:29:00.000-08:00

At Idealab, I helped start eSolar just a few years ago. Back then it was concepts and computer models. Now they are building solar thermal power plants in the high deserts of California which use heliostat fields to concentrate sunlight onto a tower. The focused heat from these mirrors generate steam which can be used to create electricity. There's been buckets of progress since we started eSolar and now they are on CNN!

Here's a picture of me visiting one of eSolar's early test sites back in May, 2008.

Kobayashi, Maskawa and Nambu win Nobel Prize

2008-10-07T22:00:00.000-07:00

Makoto Kobayashi, Toshihide Maskawa and Yoichiro Nambu shared the 2008 Nobel Prize in Physics. This is great news to me, not only because these are great men with great contributions to Physics, but because my research focuses on measuring a component predicted by their theory, namely Vud, a component of the Cabbibo-Kobayashi-Maskawa matrix. The CKM matrix describes the degree to which the six known flavors of quarks mix together. In their model, Kobayashi and Maskawa assumed that there are three generations of quarks, (each with two quarks.) Measuring Vud and other CKM matrix components to high precision is one way to directly test that assumption.

New York Times: Three Physicists Share Nobel Prize

Is rapid prototyping environmentally responsible?

2008-05-16T17:47:00.000-07:00

In a recent article in Desktop Engineering it was asked "How Green is Rapid Prototyping?" 'Good question', I thought. I took interest in this as I have worked for both Desktop Factory and two solar power companies Energy Innovations and eSolar. Tough question too. At least for all rapid prototyping that I have used at Idealab, this goes beyond whether the printing process uses more or less material than other methods, because rapid prototyping has let us avoid whole wasteful stages of other production methods such as plastic mold making, which consumes much energy and metal.

From a long-term perspective, Cathy Lewis, CEO at Desktop Factory, believes that most professionals don't think about the end-use of their products. For parts produced on her company's systems, Lewis says they are looking at ways to break down any support structures for easier recycling. Customers can mail unused powder back to the headquarters and get a discount on new material. Desktop Factory is also working to understand such questions as, how many times can unused powder be put back into the machine for reuse?

Solar Energy for Heat, Light and Power

2008-05-09T09:03:00.000-07:00

My friend and mentor, Professor Roland Winston, of U.C. Merced, gives a talk on non-imaging optics for developing solar concentrators.

Quote of the day: Skeptical Essays

2008-05-06T17:16:00.000-07:00

What is wanted is not the will to believe, but the will to find out, which is the exact opposite.

Bertrand Russell, 1928

Now Featuring Javascript LaTeX

2008-04-28T11:15:00.000-07:00

From my previous post, Bloggin' LaTeX, you may have seen that, although we could display a LaTeX string by connecting to the CodeCogs server and generating a LaTeX equation image. But it had a flaw. It wasn't reversible. Once Blogger got a hold of the mangled URL

function displayequation(latex)
{
    document.write("<div align='center'>");
    document.write("<img src='http://www.codecogs.com/eq.latex?" + latex + "' alt='" + latex + "' />");
    document.write("</div>");
}

Now inserting an equation is as simple a writing

<script>displayequation("E = mc^2")</script>

which produces the beautiful equation Now, we have something that is completely reversbile and reusable. Blogger won't mess with the link and butcher your LaTeX string. For example, let's say you accidentally write

<script>displayequation("E = mc^3")</script>

This wont do at all. But now you can simply edit the string and fix the problem without having to start from scratch.

Image Recognition Software on a Cellphone

2008-04-25T18:19:00.000-07:00

A few years ago I worked with Evolution Robotics and Idealab on a project to prototype an image recognition system for cell phones. We tested and deployed prototypes in Japan. Well, it's really taken off since those early days and now it's in the news. The product, developed by Bandai Networks for KDDI, is being called ER Search and it is based on Evolution Robotics' ViPR® (Visual Pattern Recognition) technology. It should soon be available here in America.

ViPR® Visual Search on the iPhone

ER Search in the News

Bloggin' LaTeX

2008-04-23T00:01:00.000-07:00

I really want LaTeX on this blog so I looked into a few options. One possible choice was WolerineX02. Here is the first attempt,

But there's the problem. It's not reversible. It generates a picture but without a "alt" tag with the LaTeX so that if you make a mistake you are screwed. Also, it doesn't seem to render using the standard LaTeX engine so the quality of the pics don't quite cut it for my taste.

Another fun widget is this Google Gadget. This fun gizmo lets you edit equations with buttons and LaTeX, and then save the lovely resultant images.

But I really wanted something that generated equations from standard LaTeX embedded right in my blog post so that I didn't need to upload images, and not just an equation editor. Here is one example. I think it wins first place for quality, what do you think?

Next, I tried the CodeCogs Equation Editor which lets you embed the LaTeX in the URL directly so you don't need to install a translation script for your editor. The images are much cleaner,

You just insert the HTML

<div align="center">
  <img src="http://www.codecogs.com/eq.latex?\tiny \int_{-\infty }^{\infty }e^{-x^{2}}\;dx=\sqrt{\pi }" />
<div>

and it downloads the image automatically. A complete description of how this can be used with WordPress can be found at sixthform but it works just fine with blogger too, or any HTML. It just be reversible and reusable without a script that is meant to run on a Wordpress server.

Then you can also insert an inline equation similar to using LaTeX's "$...$" feature using

<img src="http://www.codecogs.com/eq.latex?e^{\pi i}=-1" title="e^{\pi i}=-1" alt="e^{\pi i}=-1" style="vertical-align:-0.5em;" />

which would produce right inline with your text but lowered so that it doesn't look like this floating in the air.

Quote of the day: Earth Day 2008

2008-04-22T12:55:00.000-07:00

I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.

Thomas Edison, 1931

U.S. Patent 7,266,236 was issued.

2007-09-04T20:11:00.000-07:00

Accelerated handwritten symbol recognition in a pen based tablet computer Hickerson, et al.

Abstract

The present invention provides a method and apparatus for accelerated handwritten symbol recognition in a pen based tablet computer. In one embodiment, handwritten symbols are translated into machine readable characters using special purpose hardware. In one embodiment, the special purpose hardware is a recognition processing unit (RPU) which performs feature extraction and recognition. A user inputs the handwritten symbols and software recognition engine preprocesses the input to a reduced form. The data from the preprocessor is sent to the RPU which performs feature extraction and recognition. In one embodiment, the RPU has memory and the RPU operates on data in its memory. In one embodiment, the RPU uses a hidden Markov model (HMM) as a finite state machine that assigns probabilities to a symbol state based on the preprocessed data from the handwritten symbol. In another embodiment, the RPU recognizes collections of symbols, termed "wordlets," in addition to individual symbols.

U.S. Patent 7,261,542 was issued.

2007-08-28T01:01:00.000-07:00

Apparatus for three dimensional printing using image layers Hickerson, et al.

Abstract

A three-dimensional printer adapted to construct three dimensional objects is disclosed. In an exemplary embodiment, the printer includes a first surface adapted to receive a bulk layer of sinterable powder, a polymer such as nylon powder; a radiant energy source, e.g., an incoherent heat source adapted to focus the heat energy to sinter an image from the layer of sinterable powder; and a transfer mechanism adapted to transfer or print the sintered image from the first surface to the object being assembled while fusing the sintered image to the object being assembled. The transfer mechanism is preferably adapted to simultaneously deposit and fuse the sintered image to the object being assembled. The process of generating an image and transferring it to the object being assembled is repeated for each cross section until the assembled object is completed.

Beam It Down From the Web, Scotty

2007-05-07T09:35:00.000-07:00

I was mentioned in the New York Times! Saul Hansell wrote a great article, Beam It Down From the Web, Scotty, on the three dimensional printer being developed by Desktop Factory that I helped create.

In a brainstorming session, Kevin Hickerson, an IdeaLab engineer, proposed the method the company would ultimately choose. First the machine spreads a powdered plastic over a roller, which is heated to just below the plastic’s melting point. Then a sharply focused beam of light melts dots of plastic on the roller. After the unmelted powder is brushed off, the roller deposits the hot plastic onto a platform. This process is repeated until the object is assembled from the bottom up.