Friday, May 16, 2008

Notes from April 9th

Just brought out of the archives...notes from April 9th.
This is a day when I was considerably late to class (in large part due to a screwy RTS schedule, but let's not go there)

On this day, Jeff (Pelz) and Andy (Herbert), the Vision and Mind lecturers respectively, came in to answer some of our questions.

This is based on the notes from another student who was there the whole time; while looking at the notes, I am trying to convert her note style into mine.
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* The world is broken down into little pictures, which your brain then puts together
* Since the system as a whole is so complex,. it helps to look at simple individual signals
* Yet, how does the brain combine these inputs into what is perceived as a smooth image? We don't know.

There exists something called the "binding problem" - action potentials [of the signals a neuron sends] are all-or-nothing, so the rate code (data speed and built in redundancy) is important
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[Editor's note: The following section has to do with a question I brought up often during this topic; i.e. what happens when something goes wrong in the system; and conversely, when someone has a sensory deficiency, what brain components are malfunctioning?

The prominent existence of NTID here at RIT has brought this type of question to the forefront of my mind. (yes, I know that the topic refers/referred to vision problems, but that is something I commonly find, that one topic jogs my memory on a somewhat-related topic. Furthermore, I recall from the lectures that several sensory areas are located in the same brain lobe, implying to me that they have interconnected or similar functions.)

Colorblindness was the main thing discussed in response to this question.

* With cataracts, the cornea is yellowing, warping the perception of certain wavelengths, especially on the blue end of the spectrum
* A lot of colorblindness has to do with errors in the retina's system of cones, which perceive color
** Some colorblind people don't have any, or the cones are not wired together properly

* Humans are trichromats, which perceive three different colors (R, G, B), and have different sets of cones that specialize in each. [this presumably in addition to light/dark white/black]. Soem humans are dichromats, which would logically mean a form of colorblindness compared to normal human perception.

Many animal species are bichromats or tetrachromats.

(At about this point of Andy & Jeff's talk, I show up and begin taking my own notes, that original post being located here: http://alan-labbook.blogspot.com/2008/04/questions-answered-by-andy-jeff.html)

[With the following comments, I'm not knocking the person who have me notes for 4/9, just stating facts/observations]

I notice that her style has more data fragments than mine does. (Granted, in the interest of keeping up the pace during the lectures, I often didn't use 100% complete sentences)

I find that different details are pulled out, but with the same general areas covered.

Note-taking is basically summarizing, and that's a task that different people ar eobviously going to approach differently.

Friday, May 9, 2008

Today's activity

Our tour guide - a Dr. Ferran

This is a bioscience research lab that I share with a couple other faculty

Dr. Sweet's aquarium - large amount of pencil urchins
She is a developmental biologist - studies organisms' gestation/etc.

Dr. Newman - human geneticist; studies generic patterns of age-related deafness
Human genetics & molecular analysis

Lots of collaboration in here with other people in the field

A lot undergraduate research assistants [they atleast get credit for it]

We don't run in to too many problems with the animal-welfare and religious-fanatic types

The Human Genome Project - provided a lot of raw data that we're just beginning to work with.

"Why couldn't God have released the source code with the binaries?" :P
More work needs to be done on proteins, though ("the devil's in the details.")


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We are now in cell-culture room
Not sterile but still above-average cleanliness
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UV lightboxes have a sterilization effect

Some issue of our body contaminating the experiment, rather than the experiment contaminating us. (The types of pathogens we work with aren't seriously harmful to humans)

Thursday, May 8, 2008

Big Bang and Black Holes: Topic Outline

What is important about the Big Bang And Black Holes topic?
I'd say it goes something like this...

1) "In the beginning..."

1.1) Singularity of infinitely small volume (and thus infinitely high temperature and pressure
1.2) This exploded/expanded - that event is the Big Bang itself

2) How do we know?

2.1) Hubble's Law - universe is expanding
2.1.1) Illustrated by Redshift [Light wavelength changes thanks to a stretching of the medium - space)
2.1.2) Extrapolate this backwards, and the universe would have been infinitely small at one point.

2.2) Cosmic background radiation
2.2.1) Remnants of the Big Bang explosion
2.2.2) Residual temperature in the universe of a few degrees Kelvin

2.2.3) Small temperature variations in this radiation - matter clumps; this clumping eventually aggregated itself into galaxies

3) What happened after the Big Bang?

3.1) Freeze-out of the "fundamental forces" - strong force, electromagnetic force, weak force, gravity [They used to be of equal strength, now they aren't - I just listed them in strongest-to-weakest order]

3.2) Inflationary Period
3.2.1) Especially rapid period of expansion in early universe (< 1 sec after BB)
3.2.2) Without it, the early universe would have had to have been relatively larg ein order to have reached the current size

3.2) Energy to Matter
3.2.1) E = M * C^2 : energy can be converted to matter...energy takes up less space than matter
3.2.2) Balance of matter annihilating antimatter, eventually regular matter won out
3.2.2.1) We don't know why regular matter won out

3.2.3) Big Bang Nucleosynthesis
3.2.3.1) Roughly 3min after BB. Occurred at temperature of 10^9 Kelvin
3.2.3.1) Particles coalesced into atoms
3.2.3.2) BBN only would have lasted long enough to form light elements.
Universe is made up of predominately light elements, this lending support to this important part of the Big Bang model
Various isotopes of hydrogen, helium, lithium and beryllium were formed

3.3) Later, stars and galaxies develop

4) The Cosmological Principle: important concept
4.1) Isotropic: Large-scale structure looks the same in all directions
4.2) Homogenous: General physical properties of the universe are the same everywhere in it
Thus, the universe has no edge and no center

5) What are galaxies?

5.1) The Formation of Galaxies
5.1.1) Galaxies formed about 1 billion years after big bang
5.1.2) Hierarchical merging [smaller-scale version of this process likely forms solar systems]

5.2) Different galaxy shapes

5.2.1) Spiral - a disk with spiral arms. Our own Milky Way is one. Relatively small nuclear bulge. Relatively large amounts of young stars and star formation.
5.2.2) Elliptical - Dominated by spheroid. Relatively old
5.2.3) Irregular and Peculiar - Those terms mean what you think they mean. :)

5.3) Galaxy relations: Galaxy clusters, superclusters

5.3.1) Galaxies do gather into clusters

5.3.2) Supercluster Types
5.3.2.1) Rich - >1000 galaxies, giant central galaxy
5.3.2.2) Poor - 10 to 1000 galaxies, more spirals
5.3.2.3) Isolated galaxies - even more likely to be spirals

5.3.2) Galaxies in superclusters not gravitationally bound to each other

6) What are black holes?
A superdense object, to the point where its gravity is so strong that not even electromagnetic radiation [light] can escape

6.1) Fuller explanation of black holes is provided by Einstein's theories of relativity

6.1.1) Spacetime - space and time are connected (they are *relative* to each other)
6.1.2) Gravity is dependent on spacetime
6.1.3) Special relativity predicts/explains unusual behavior that occurs with abnormal values of space, time, and/or gravity

6.2) Now, if no electromagnetic radiation, visible light or otherwise, emerges from a black hole, how do we study them?
6.2.1) Their effect on visible bodies near them: For ionstance, a black hole may suck in gas from nearby stars

6.3) Black holes are the Las Vegases of the universe - what happens [goes into] in a black hole stays in a black hole.
6.3.1) This is how black holes build mass
6.3.2) Difference: Actions in Las Vegas may also cause alimony, child support or prison time to increase

7) Dark Matter and Dark Energy: The Monkey Wrench in the Cosmological Works
We don't know what it is; hence the name 'dark'.
Nonbaryonic ("Baryons" are a type of particle with protons and neutrons being the most notable examples of them)

7.1) Composes most of the universe


7.2) Dark matter:
7.3) Dark energy: even more "weird" than dark matter

-More to come-

Wednesday, May 7, 2008

Visit to Jeff Pelz in his image lab

Wearable eye tracker vs. lab-based eye trackers

* In-lab: Purkinje eye trackers: Purkinje is reflections off of the eye, a "glint in someone's eye"

* Investigate different questions in different envirnoments
* Limitations of the lab: people may behave differently in a lab environment, and Perkingi trackers require the head to be immobilized
* In-lab equipment has faster frequency and higher accuracy

* SOme equipment is based on video cameras rather than eye-trackers

When reading: small smooth movement ( a word) with jumps to the next word and the next line. Sometimes regression moments to rereread something

In our terms, a "gaze" is when you look at one object, rather than an entire scene, but w/o keeping your head/eyes totally still
Modeling gaze: what you fixate on in an image, how long, and why. | By modeling gaze, build a model of what you think people will look at, and compare it with experimental data

In 1/10 of a second, you get the general idea of an image (i.e "This is a kitchen")

bottom-up: start with pixels and then form a concept
top-down: start looking for a concept and then doscover the details [i.e. pixels]
For top-down you need to have an understanding of the concept you are looking for

Friday, May 2, 2008

Notes from the semiconductor lab we visited last week [April 25th]

We visited a semiconductor facility a week ago; this is on the RIT campus as part of the engineering program's apparatus (specifically, Microelectronic Engineering)

The most obvious thing is the 'clean' in 'clean room', and some of the cleanliness measures employed were rather interesting.

It's a Class 1000 cleanroom, meaning them aim for less than 1000 particles per cubic foot.

For instance, outside laptops weren't allowed in (because of dust & related crud that may be in the keyboard), so this post is actually a rough transcription of my paper notes [plus some additional commentary on the lab].
For really hardcore microelectronics engineers, there's special paper that 'sheds' less particulates into the air.
The full-body suits were interesting and amusing-looking, we collectively looked like future astronauts or something.

Air pressure is slightly higher inside, so that clean air rushes out and dirty air doesn't rush in when access doors are opened

The day before our visit was "Bring your Son/Daughter To Work Day", and our tour guide remarked that the gaggle of 5-year-old present looked rather cute after bieng outfitte din the suits.

Sodium is a really bad contaminant. [editor's note: so no salty munchies in the lab!]

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Anyway, their equipment is sufficient to produce microchips from beginning to end, but it's all atleast a few years old. (and thanks to Moore's Law, that makes the chips quite out of date; but the value is there as an educational tool.) Furthermore, most of the equipment was donated by
big names in the field (such as IBM and Intel) after *they* upgraded.

Furthermore, consumer-photography companies like Canon, Nikon, and Kodak are also involved in this type of industrial equipment. [The photoresist process, important to semiconductor manufacture, does involve exposing the silicon wafer to a certain amount and type of light in certain areas of the chip.]

Makes sense in a way, because as is common for RIT, grads often end up going right work with one of the big-name companies in their field
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So, roughly speaking, how does the process actually work?

* A block of processed silicon is 'sliced' into wafers, and each of those wafers will become a large quantity of chips over the course of the manufacturing process. Thus, each batch of microchips necessarily contains a large number of individual chips.
* With lithography, a printing process, computer-designed patterns are put onto the wafer
* Then we apply photoresist; we apply it over certain parts of the wafer, so that some areas of the chip 'resist' when exposed to light and some won't [this forms the pattern]
* The photoresist is exposed by a certain wavelength of blue light from one of the lab's machines

To prevent accidental exposure, the lightbulbs in that area are yellow and the windows are tinted. I recognized this as being analogous to the use of red-colored lightbulbs in traditional photofilm darkrooms.

* Ion bombardment, towards the end of the process implants material into the wafer that makes it more conductive. (Yes, we discussed silicon for quite a while before mentioning implants. :))
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Dangerous chemicals are important to the semiconductor process, but one sign in the lab touched upon this with a note of humor:
"You can walk on a wooden leg, you can eat with false teeth, but you can't see with a glass eye. So wear your safety glasses."

Wednesday, April 30, 2008

Personal Interest Presentation: outline-in-progress

I'll edit this post as I develop more ideas for my outline

"Space, the final NanoPower frontier"

[Insert badly photoshopped picture of the Enterprise]

0)
Nanotech has potential in all areas of space exploration.
Nanotech will not immediately create new fields/devices, but rather, it has the potential to greatly improve existing devices. (especially in the near future)

0.1) Short overview of why we should be trying to use nanotubes (reference their positive charcteristics)

1) Existing use of nanotech in space
1.1) Space Nanotechnology laboratory at MIT (snl.mit.edu) has used nanotehc to build nanoscale components of NASA observers [Chandra X-Ray and others]

2) Nanoelectrical systems

2.1) Power systems, PMAD [Power Management and Distribution] systems
2.1.1) Applications in nuclear powersystems
2.1.2) Applications in solar powersystems

2.2) MEMS [Microelectromagnetic systems]: Combine microchips with electronics that would use them.
2.2.1) Important spacecraft electronics could be made smaller.
2.2.2) Micro-probes for imaging extraterrestrial objects

3) Nanocomposites as a spacecraft building material

3.1) "Armoring" against space debris
3.2) Useful in dealing with stresses of launch?

4) Types of space exploration; usage of nanotechnologies there

4.1) Deep-space travel
4.2) Colonization of extraterrestrial worlds

4.3) Surface exploration [using nanotech]
4.3.1) by humans

4.3.2) by probes/robots
4.3.2.1) Nanotechnology could enable you to build very small probes.

5) Use of nanotubes to transport stuff from Earth to low-Earth orbit
5.1) A space elevator?
5.1.1) Exciting theoretical possibility, but even the theory isn't completely ironed out yet.

* Many parts of this presentation will reference concepts discussed during Ryne Rafaelle's two presentations way back in Week 2. My notes are on this blog, and I still have access to the powerpoints, so memory of that material shouldn't be an issue.

Personal Interest Presentation

This is the "final exam" for the Frontiers of Science class.
The idea here is to zoom on on sub-area(s) of any of the four topics covered, specifically sub-area(s) that especially interest you

I am focusing on the use of nanotechnology and NanoPower in current and future space exploration. To put it more lyrically,

"Space, the final NanoPower frontier"

To be honest, good sci-fi works can have quite a potential to be inspiring as to the course of scientific advancement.

A centerprice of our classroom is a widevision screen that, among other things, could display 4 PowerPoint-type slides at a time, and we have a PowerPoint template file designed to work with that.

The crux of my Personal Interest Presentation s going to be one of those, which is a process I've also used for the three topic summaries I've done to date.
The format is one I understand, and I'm also using it because I'll hopefully be able to focus on content rather on the logistical & production issues of a more exotic format