Elastomeric Grating for Wavelength Switching in Optical Communication Systems
A diffraction grating was fabricated from an elastic polymer. It was patterned after a plane reflection grating with a pitch of 1200 lines/mm. It was characterized using a HeNe laser to verify properties. Angular scanning as a function of applied strain was observed for two individual wavelengths. Intensity of fiber output was optimized as an application of angular scanning in fine alignment. Beam profiles showed consistency of first order diffraction intensities at different levels of strain. This showed that the elastomeric grating’s efficiency is independent from strain. The elastomeric grating’s variable pitch can be of immense utility in optical communication systems. A stretchable grating can be used to replace typical high-cost architectures of metal or glass gratings of different pitches that correspond to various spectral regions. By changing the pitch, the grating can be used for different wavelength ranges. The elastomeric grating’s variable pitch can be used to scan different wavelengths over a wide range of angles. Angular scanning is used for wavelength channel selection, and since an elastomeric grating diffracts different wavelengths differently, it can be used for wavelength switching and wavelength division multiplexing in optical communication systems. Laser beams of different wavelengths carrying different signals can be transmitted simultaneously through an optical fiber and diffracted to route the wavelengths onto separate wavelength-specific channels.
Reflex Charging Frequency
Reflex charging, or burp charge, is a prove method of effectively charging secondary\r batteries under extremely high current. It is commonly used in military and aerospace\r applications where short recharge time and long cell life are essential. Eric C. Darcy, a NASA\r chemical engineer, in his 1998 PhD thesis, ‘Investigation of the response of Ni-MH cells to\r burp charging’, outlined some of the most important theories behind this seemingly\r miraculous technique. However, due to the technical limitations of his equipment, Darcy was\r unable to determine the effects of varied reflex charging frequencies. This research overcame\r this problem by using a purposed built multi-frequency programmable reflex charger\r (PRESTO ALPHA I), and aimed to optimize chemical energy storage by searching for an\r optimum charging frequency.
The Beam of Hope
As the most dominant species on planet Earth's surface, humans have become the sole protectors of the planet, in charge of keeping it hospitable for billions of species. However, a swift look around Egypt's streets in contemporary 2007 showed proof of our exploitive use of fossil-fuels. Provoked by such a scene, I set out to discover the negatives of fossil-fuel consumption that more than 2 million websites were ready to detail. The increased CO2 emission, due to fossil-fuel use, is contributing to the greenhouse-effect, causing global-warming and thus leading to climate-change. This affects biodiversity by causing the eventual extinction of species, thus upsetting food-chains and affecting humanity in the long-run. Statistically 40 more years of consumption are left if the current rate-of-consumption persists. My proposal is to use solar-energy as an alternative power-source. Two requirements must be fulfilled: it must hold research potential and shouldn't suffer from problems associated with fossilfuels. 3rd-generation nanocrystalline dye-sensitised solar-cells have a conductive-glass-electrode coated with titanium-dioxide, then a layer of dye on it for light-absorption, electrolyte and finally a counterelectrode coated with graphite.\r In the dye-experiments, dyes extracted from fruits & vegetables, and the wavelengths of visible-lightspectra that they absorb, were examined using a UV-spectrophotometer. The solvent for the extraction-process was tested and ethanol was better than water because it actively extracts the dye while water doesn't help and contains ions that alter the dye's absorption-abilities. I combined 2 dyes: chlorophyll (absorbs the red & violet areas in spectrum) with blackberry (absorbs the green area) thus enabling the solar-cell to absorb the entire spectrum and maximising its power-reading. I investigated whether the dyes should be freshly-mixed or combined earlier (and used every time to build the cell). Freshly-mixing dyes is better because that stops the enzymes that were extracted out with the chlorophyll from denaturing blackberry's anthocyanins and rendering them dysfunctional thus the dyes work better maximising the power. Testing the dye-combination's concentration showed that the 6.25% concentration is the best because it can coat the TiO2 with a single-layer of dye instead of high concentrations that give multiple layers of dye which doesn't give good electron transition or low ones that don't give enough dye which means a lower amount of electrons are being excited and thus less power. In the material-section, anatase and rutile, TiO2's 2 major constituents (structurally identical but with different crystal-orientation), were compared and anatase proved itself better because of its smoother conduction-band. Different anatase particle sizes were examined and the smaller particles (4 nm) were better because of increased surface-area. I investigated the ways of coating the counterelectrode and found that using carbon-paste is the best. Ultimately my solar-cell's power-reading increased from 2.04 nW to 6.41 μW which is 3142 times the initial reading, a dramatic increase for a solar-cell whose size doesn't exceed 4 cm2. This proved the great research potential held by solar-energy. After extensive comparisons between the ups and downs of both fossil-fuels and solar-energy, solar-energy clearly proved itself the perfect alternative for powering our future.
Automatically Categorizing Commercial Segments Using Multiple Computer Vision Techniques
The purpose of Computer Vision is to understand the methods by which humans\r process visual information and likewise to create computer algorithms similar to these\r processes. Through careful observation, a computer algorithm was developed to mimic\r how humans recognize logos in television commercials. After visual analysis of\r numerous commercial sequences, it was hypothesized that the key frames (frames in\r which the logo resides) could be found using the intersection of color histograms; the\r logo region could be found using the edge density within the key frames; and the logo\r could be identified utilizing a correlation method with a database of stored logos, scaled\r to different levels using Bilinear Interpolation.\r Color histograms were implemented using one-dimensional arrays with 24 bins;\r key frames were determined by calculating the intersection between consecutive frames’\r color histograms. The edge density was calculated by convolving the key frame with\r the number of edge pixels within a 21X21 area. The identification of the logo was\r determined by computing the Sum of Square Differences between the logo region and\r the database of logos on different scales; SSD values were normalized for different\r scales.\r The algorithm was tested on 14 different sequences and determined the key frame\r with 80% accuracy. By segmenting the sequence into two key frames, the algorithm\r generated 93% accuracy. The algorithm also identified the logo region with 93%\r accuracy. The identification of the logo yielded anomalous results. These data suggest\r that motion between consecutive frames in commercial segments decreases around the\r display of the logo. They also suggest that the logo region has the most visible edges\r within the key frame.\r Future study includes a complete overhaul of the logo recognition algorithm. The\r correlation algorithm (SSD) does not work accurately enough to be used. Therefore, the\r next step is possibly to look at the edge information about the key frames. As the Canny\r algorithm determines the edges of an image, it has to determine the direction (or\r orientation) of the edges. Therefore, a proposed study includes utilizing an edge\r orientation histogram of the database of the logos and the key frames. This would mean\r that the algorithm would identify the logo in the key frames by matching edge\r orientation histograms.
Transiency
Transiency… something which only stays for a short time, and changes\r frequently. You’re probably wondering now what this has to do with our sports and\r we must admit that at first sight it really doesn’t seem to, but think of the world an\r how many changes sports have experienced. Is it not time we thought of how sports\r facilities could be improved? And what if you were told that there would be an\r “ever-changing” sports centre which you could use?\r You really might get the chance to use such a sports centre one day, and that’s\r what our idea is all about. A multipurpose sports center is what you could call it, but\r it’s not in the least like any one you’ve seen before. In places like Hong Kong, where\r space is everything, multipurpose sports centers are common, but they always have\r so many colored clines that tend to confuse both players on the court and spectators\r off the court. Just how often have you seen referees and players arguing about\r whether the ball is out or not? And how often have you found that you are not\r enjoying the game as much as you should? Yup, we’re sure it happens all the time,\r but you don’t have to worry anymore, as our innovative design will solve all your\r problems. Yes, its time for us to change…\r In our dream sports mat, we’ll have lines which can change and also detectors to\r tell you where the balls land. You’re probably thinking, “Lines which change?”, and\r yes that’s it! The perfect solution to all those confusing lines would be lines which\r could change their positions. And to do this, we’ve made use of some new technology\r called ‘E-INK’ which would make this possible. Of course it sounds like something\r which is really costly but in fact, this technology doesn’t cost that much and its really\r durable, so it’s really worth the money to start changing. Moreover, these mats can\r also be rolled up and stored somewhere else, so when you don’t need to use the sports\r ground you can just pack it up and the venue can be used for other purposes.
Stimuli-responsive Fullerene Grafted Polymers for Enhanced Drug Delivery Applications
The physiochemical properties of fullerenes have aroused wide interest, such as its ability to accept and lose electrons and relatively high reactivity that permit various modes of structural modifications. However, obstacles to further research include its complete lack of solubility in water and low processability.\r This project investigated the morphology and microstructure of a fullerene-grafted polymer as a potential candidate for better and novel systems for drug delivery. In this research, hydrophilic functionalities were introduced to the C60 fullerene by chemical modifications, through the attachment of poly(acrylic acid) (PAA) chain. The objective was to investigate the dynamics and the self-assembly properties of this polymer in aqueous solutions, and the knowledge gained would enhance the development of such system for potential applications in drug delivery and nanotechnology.
Image Compression Program Using Different Fractal Formulas
File compression has become a very important tool in the technology field because it allows faster data transfer rates over the internet and decreased file size on data disks. File compression aims to reduce file size while still retaining the quality of the file. Lossy file compression methods are not very efficient because the compressed files end up losing more data than what is usually intended causing a considerable loss in quality. Lossless file compression methods, on the other hand, take time to process since they require decompression to retrieve the original file. In this study, a lossless algorithm which does no require decompression was created. The resulting Fractal File Compression (FFC) algorithm contains two parts, the IFS algorithm and the Huffman Tree generator. Both algorithms were created using Java language and JCreator. The finished program was tested on an image file with 2542 x 1944 pixels dimensions. The image file was compressed using JPEG, BMP, PNG and FFC formats. For each method, the image file was compressed at three different resolution settings; low, medium and high. All the compressed images were then viewed under 500% zoom using Adobe Photoshop CS2. In an area of 40 by 40 pixels, the number of distinct boxes, which served as a measurement of image quality, was determined. Compressed images for JPEG, BMP, and PNG for both the low and medium settings have low image qualities, while the fractally-compressed images have a high image quality. For the high resolution setting, both JPG and fractally-compressed images have Page 2 of 2 high qualities while BMP and PNG still have low qualities. Based on the measurements obtained from the box-counting method and the file sizes, the absolute image quality for each compressed image was calculated. The absolute image qualities of the compressed images used for each setting were then compared. Coupled with large file size and small pixels per area count, the conventional methods have lower absolute image quality than the images compressed using the FFC method. This was true for the low and medium settings, however, JPG compression has a higher absolute image quality than the fractally-compressed images. This meant that JPG compression is more efficient than fractal compression when an image has a high resolution. The resulting FFC algorithm is lossless since it uses pattern searches and replacements in order to decrease the file size. To make the program more suitable for high resolution images, the FFC algorithm may be modified. Most of the changes in the FFC algorithm should be done in the IFS generator. High resolution images can be compressed fully if the pattern that was used for compression is more representative, but even shorter. A more representative bit pattern would create a high quality, high resolution image with a smaller file size.