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I made this jet engine to demonstrate how a pulse jet works and to show were the fundamentals of powered aviation all began. I also made this project to gain more knowledge, due to my interests in engineering and turbines. I would also like to measure the thrust of this model in the future. And hopefully this might inspire other people to use this type of engine in their model aircraft.

Many people in South Africa still use open fires for cooking. There is a\r large amount of wasted heat lost by four methods of heat transfer:-\r radiation, convection, conduction and evaporation.\r I constructed a vessel that would reduce heat loss, and focus the heat\r emitted from a fire onto the bottom of a pot. I used materials that were\r cheap and easy to obtain, so that those using open fires would be able to\r construct similar vessels to save energy and reduce pollution.\r The vessels were made up of a standard wire mesh frame that was\r surround by trial coverings, namely tin foil, asbestos rope, industrial foil,\r papier mache, ceramic, and 2 ceiling insulators.\r 5 mls of methylated spirits was burned in each vessel. The temperature\r gain of 100mls of water in a standard pot was recorded. 5 trials on each\r vessel were performed. 2 groups of vessel were found. Those that\r produced high temperature gains, burned quickly, and produced a large\r amount of soot deposits on the pot, and a second group that did the\r opposite.\r I compared the rate of heating from my best vessel to that of a stove as\r well as a microwave oven. Heating from the vessel was faster than that of\r the stove, and slightly slower than the microwave.\r I measured the heat emitted from a fire in a three-dimensional pattern and\r found that the maximal heat was some distance above the flame.\r From these results I devised 12 guidelines that would minimize the\r energy need, and pollution produced, when cooking on an open fire

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.

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.

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.

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.

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.