Friday, November 24, 2006
M Processing
Mesoscale oceanographic features are important aspects of ocean circulation. The high volume of satellite-derived oceanographic data coupled with the high level of human skill associated with the detection of oceanographic features in the data has necessitated automating the interpretation process. Morphological edge detectors produce better results than the conventional template- and differentiation-based edge detectors. A grayscale morphological edge-detection algorithms is developed for automatic delineation of mesoscale structure in digital satellite IR images of the ocean. We compare performances of three morphological edge detectors in sea surface temperature fields. We provide experimental results on images from the North Atlantic under various image settings.
Wednesday, November 22, 2006
Nanotechnology
Manufactured products are made from atoms. The properties of those products depend on how those atoms are arranged. If we rearrange the atoms in coal we can make diamond. If we rearrange the atoms in sand (and add a few other trace elements) we can make computer chips. If we rearrange the atoms in dirt, water and air we can make potatoes.
Todays manufacturing methods are very crude at the molecular level. Casting, grinding, milling and even lithography move atoms in great thundering statistical herds. It's like trying to make things out of LEGO blocks with boxing gloves on your hands. Yes, you can push the LEGO blocks into great heaps and pile them up, but you can't really snap them together the way you'd like.
In the future, nanotechnology will let us take off the boxing gloves. We'll be able to snap together the fundamental building blocks of nature easily, inexpensively and in most of the ways permitted by the laws of physics. This will be essential if we are to continue the revolution in computer hardware beyond about the next decade, and will also let us fabricate an entire new generation of products that are cleaner, stronger, lighter, and more precise.
It's worth pointing out that the word "nanotechnology" has become very popular and is used to describe many types of research where the characteristic dimensions are less than about 1,000 nanometers. For example, continued improvements in lithography have resulted in line widths that are less than one micron: this work is often called "nanotechnology." Sub-micron lithography is clearly very valuable (ask anyone who uses a computer!) but it is equally clear that conventional lithography will not let us build semiconductor devices in which individual dopant atoms are located at specific lattice sites. Many of the exponentially improving trends in computer hardware capability have remained steady for the last 50 years. There is fairly widespread belief that these trends are likely to continue for at least another several years, but then conventional lithography starts to reach its limits.
If we are to continue these trends we will have to develop a new manufacturing technology which will let us inexpensively build computer systems with mole quantities of logic elements that are molecular in both size and precision and are interconnected in complex and highly idiosyncratic patterns. Nanotechnology will let us do this.
When it's unclear from the context whether we're using the specific definition of "nanotechnology" (given here) or the broader and more inclusive definition (often used in the literature), we'll use the terms "molecular nanotechnology" or "molecular manufacturing."
Whatever we call it, it should let us
Get essentially every atom in the right place.
Make almost any structure consistent with the laws of physics that we can specify in molecular detail.
Have manufacturing costs not greatly exceeding the cost of the required raw materials and energy.
Todays manufacturing methods are very crude at the molecular level. Casting, grinding, milling and even lithography move atoms in great thundering statistical herds. It's like trying to make things out of LEGO blocks with boxing gloves on your hands. Yes, you can push the LEGO blocks into great heaps and pile them up, but you can't really snap them together the way you'd like.
In the future, nanotechnology will let us take off the boxing gloves. We'll be able to snap together the fundamental building blocks of nature easily, inexpensively and in most of the ways permitted by the laws of physics. This will be essential if we are to continue the revolution in computer hardware beyond about the next decade, and will also let us fabricate an entire new generation of products that are cleaner, stronger, lighter, and more precise.
It's worth pointing out that the word "nanotechnology" has become very popular and is used to describe many types of research where the characteristic dimensions are less than about 1,000 nanometers. For example, continued improvements in lithography have resulted in line widths that are less than one micron: this work is often called "nanotechnology." Sub-micron lithography is clearly very valuable (ask anyone who uses a computer!) but it is equally clear that conventional lithography will not let us build semiconductor devices in which individual dopant atoms are located at specific lattice sites. Many of the exponentially improving trends in computer hardware capability have remained steady for the last 50 years. There is fairly widespread belief that these trends are likely to continue for at least another several years, but then conventional lithography starts to reach its limits.
If we are to continue these trends we will have to develop a new manufacturing technology which will let us inexpensively build computer systems with mole quantities of logic elements that are molecular in both size and precision and are interconnected in complex and highly idiosyncratic patterns. Nanotechnology will let us do this.
When it's unclear from the context whether we're using the specific definition of "nanotechnology" (given here) or the broader and more inclusive definition (often used in the literature), we'll use the terms "molecular nanotechnology" or "molecular manufacturing."
Whatever we call it, it should let us
Get essentially every atom in the right place.
Make almost any structure consistent with the laws of physics that we can specify in molecular detail.
Have manufacturing costs not greatly exceeding the cost of the required raw materials and energy.
Edge Detection
A commonly held belief that edge detection is the first step in vision processing has fueled a long search for a good edge detection algorithm. Edge detection refers to the process of identifying and locating sharp discontinuities in an image. Edges are defined as discontinuities in the image intensity due to changes in scene structure. These discontinuities originate from different scene features and can describe the information that an image of the external world contains. Enhancement and smoothing attempt to make these discontinuities apparent to the detector, so that desirable edges can be extracted.
Edge detectors, where ground truth not available, are evaluated by their ability to produce edges that provide for the quick and accurate recognition, as judged by humans, of a three dimensional object from a grayscale image of the object in its natural setting. From a complete evaluation methodology was determined that a statistically significant difference exists in the relative performance of edge detection algorithms. The relative performance depends on the method used for selecting the input parameters, as significantly better performance was attained by the edge detectors when the parameters of each were optimized individually for each image than when a single set of parameters was optimized for the entire set of images.
Edge Detection Important For Feature Extraction and Subsequent Vision Tasks : Texture Analysis, Motion Detection/ Estimation, Stereopsis and Recognition in both Machine and Biological Vision Systems.
Edge detectors, where ground truth not available, are evaluated by their ability to produce edges that provide for the quick and accurate recognition, as judged by humans, of a three dimensional object from a grayscale image of the object in its natural setting. From a complete evaluation methodology was determined that a statistically significant difference exists in the relative performance of edge detection algorithms. The relative performance depends on the method used for selecting the input parameters, as significantly better performance was attained by the edge detectors when the parameters of each were optimized individually for each image than when a single set of parameters was optimized for the entire set of images.
Edge Detection Important For Feature Extraction and Subsequent Vision Tasks : Texture Analysis, Motion Detection/ Estimation, Stereopsis and Recognition in both Machine and Biological Vision Systems.
DNA COMPUTING
The design is considered a giant step in DNA computing. The Guinness World Records last week recognized the computer as "the smallest biological computing device" ever constructed. DNA computing is in its infancy, and its implications are only beginning to be explored. But it could transform the future of computers, especially in pharmaceutical and biomedical applications.
Following Mother Nature's Lead
Biochemical "nanocomputers" already exist in nature; they are manifest in all living things. But they're largely uncontrollable by humans. We cannot, for example, program a tree to calculate the digits of pi. The idea of using DNA to store and process information took off in 1994 when a California scientist first used DNA in a test tube to solve a simple mathematical problem.
Since then, several research groups have proposed designs for DNA computers, but those attempts have relied on an energetic molecule called ATP for fuel. "This re-designed device uses its DNA input as its source of fuel," said Ehud Shapiro, who led the Israeli research team.
Think of DNA as software, and enzymes as hardware. Put them together in a test tube. The way in which these molecules undergo chemical reactions with each other allows simple operations to be performed as a byproduct of the reactions. The scientists tell the devices what to do by controlling the composition of the DNA software molecules. It's a completely different approach to pushing electrons around a dry circuit in a conventional computer.
To the naked eye, the DNA computer looks like clear water solution in a test tube. There is no mechanical device. A trillion bio-molecular devices could fit into a single drop of water. Instead of showing up on a computer screen, results are analyzed using a technique that allows scientists to see the length of the DNA output molecule.
"Once the input, software, and hardware molecules are mixed in a solution it operates to completion without intervention," said David Hawksett, the science judge at Guinness World Records. "If you want to present the output to the naked eye, human manipulation is needed."
Don't Run to the PC Store Just Yet
As of now, the DNA computer can only perform rudimentary functions, and it has no practical applications. "Our computer is programmable, but it's not universal," said Shapiro. "There are computing tasks it inherently can't do."
The device can check whether a list of zeros and ones has an even number of ones. The computer cannot count how many ones are in a list, since it has a finite memory and the number of ones might exceed its memory size. Also, it can only answer yes or no to a question. It can't, for example,
Following Mother Nature's Lead
Biochemical "nanocomputers" already exist in nature; they are manifest in all living things. But they're largely uncontrollable by humans. We cannot, for example, program a tree to calculate the digits of pi. The idea of using DNA to store and process information took off in 1994 when a California scientist first used DNA in a test tube to solve a simple mathematical problem.
Since then, several research groups have proposed designs for DNA computers, but those attempts have relied on an energetic molecule called ATP for fuel. "This re-designed device uses its DNA input as its source of fuel," said Ehud Shapiro, who led the Israeli research team.
Think of DNA as software, and enzymes as hardware. Put them together in a test tube. The way in which these molecules undergo chemical reactions with each other allows simple operations to be performed as a byproduct of the reactions. The scientists tell the devices what to do by controlling the composition of the DNA software molecules. It's a completely different approach to pushing electrons around a dry circuit in a conventional computer.
To the naked eye, the DNA computer looks like clear water solution in a test tube. There is no mechanical device. A trillion bio-molecular devices could fit into a single drop of water. Instead of showing up on a computer screen, results are analyzed using a technique that allows scientists to see the length of the DNA output molecule.
"Once the input, software, and hardware molecules are mixed in a solution it operates to completion without intervention," said David Hawksett, the science judge at Guinness World Records. "If you want to present the output to the naked eye, human manipulation is needed."
Don't Run to the PC Store Just Yet
As of now, the DNA computer can only perform rudimentary functions, and it has no practical applications. "Our computer is programmable, but it's not universal," said Shapiro. "There are computing tasks it inherently can't do."
The device can check whether a list of zeros and ones has an even number of ones. The computer cannot count how many ones are in a list, since it has a finite memory and the number of ones might exceed its memory size. Also, it can only answer yes or no to a question. It can't, for example,
Saturday, November 18, 2006
Poem
This is a poem for all my friends CASE 1: Kelly Sedey had one wish, for her boyfriend of >three years, >David Marsden, to propose to her. Then one day when >she was out to lunch >David proposed! She accepted, but then had to leave >because she had a >meeting in 20 min. When she got to her office, she >noticed on her computer she >had some e-mail's. She checked it, the usual stuff >from her friends, but then >she saw one that she had never gotten before. It was >this poem. She simply >deleted it without even reading all of it. BIG >MISTAKE! Later that evening, >she received a phone call from the police. It was >about DAVID! He had been >in an accident with an 18 wheeler. He didn't survive. > >CASE 2: Take Katie Robinson She received this poem and >being the believer >that she was, she sent it to a few of her friends but >didn't have enough e-mail addresses to send out the >full 10 that you must. Three days later, Katie went to >a masquerade >ball. Later that night when she left to get to her car >to go home, she was >killed on the spot by a hit-and-run drunk driver. > >CASE 3: Richard S. Willis sent this poem out within 45 >minutes of reading >it. Not even 4 hours later walking along the street to >his new job interview >with a really big company, when he ran into Cynthia >Bell, his secret love >for 5 years. Cynthia came up to him and told him of >her years. Three days >later, he proposed to her and they got married. >Cynthia and Richard are >still married with three children, happy as ever! > >This is the poem: >Around the corner I have a friend, >In this great city that has no end, >Yet the days go by and weeks rush on, >And before I know it, a year is gone. >And I never see my friends face, >For life is a swift and terrible race, >He knows I like him just as well, >As in the days when I rang his bell. >And he rang mine but we were younger then, >And now we are busy, tired, etc. >Tired of playing a foolish game, >Tired of trying to make a name. >"Tomorrow" I say! "I will call on Him >Just to show that I'm thinking of him." >But tomorrow comes and tomorrow goes, >And distance between us grows and grows. >Around the corner, yet miles away, >Here's a telegram received, He died today. >And that's what we get and deserve in the >end. > >Around the corner, a vanished friend. >Remember to always say what you mean. >If you love someone, tell them. Don't be >afraid to express yourself. Reach out and >tell someone what they mean to you. >Because when you decide that it >is the right time it might be too late. >Seize the day. Never have regrets. > >And most importantly, stay close to your >friends and family, for they have helped >make you the person that you are >today.
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