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On account of the rapid development of human activities, much more fossil fuel is burnt and thus a greater amount of greenhouse gases are emitted to the atmosphere including carbon dioxide (CO2). CO2, is considered as the major cause of the exacerbating global warming. “Geo-engineering”, literally, means the options that would involve large-scale engineering of our environment in order to combat or counteract the effects of changes in our atmosphere. As a carbon neutral CO2 scrubber is proposed to be a large-scale scheme to fix carbon globally through reducing the CO2 emitted to the atmosphere and our ultimate goal is to implement the CO2 scrubber scheme to the whole globe, that is, a large-scale scheme to our environment, it is a project of geo-engineering. The procedures of the project are as the following: (a)Investigating on the absorption of CO2 produced by calcium carbonate (CaCO3), using different basic substances at different temperatures (b)Investigating the absorption of CO2 in car exhaust produced by combustion of petrol in car engine using basic solid (c)Feasibility of using a prototype of CO2 scrubber in exhaust pipe of car (d)Feasibility of fixing carbon by turning CO2 into dry ice and stored in deep water (e)Feasibility of growing plant in used basic solution Results: 1.The CO2 scrubber prototype had an average CO2 removal ability over 50%, which was considered to be efficient. The concentration of CO2 (561ppm) was even lower than that in the ambient air (CO2 612ppm). During the experiment, the prototype was closely attached to the exhaust pipe and did not fall down. Thus, a CO2 scrubber was feasible to be used in the vehicles. Besides, our prototype was more energy efficient than LM2500 PE simple cycle gas turbine (consumed 21MW electricity) though our prototype had a lower CO2 removal efficiency. The cost of our prototype would be much lower than membrane technology as the production cost of the membrane was high. 2.Unlike existing CO2 scrubber prototype installed in open area (with electric fan installed), our CO2 scrubbers installed in the chimneys of power stations and exhaust pipes of cars are carbon neutral as exhaust gas has high kinetic energy and would pass into the scrubber. 3.dry ice would not evolve carbon dioxide gas at high water pressure such as at the bottom of the ocean. 4.Plants grew well in alkaline environment, it was feasible to grow plants in basic solution. Conclusion: CO2 scrubber is a suitable choice in combating the climate change through absorbing the excess carbon dioxide, with the utilization of the carbonates produced in the reaction, it is hoped that the climate change can be relieved using an environmentally-friendly device.

1. Purpose of the research\r Nowadays, many encryption software are available to computer user. However, very few people use them which result in many cases of information and data leakage due mainly over the Internet. Most people use USB Flash Drive to store and carry confident files back home to work on. When the USB Drive is lost, the files stored are often leaked. To prevent this type of incident occurring, “CryptoDefender” is developed to enhance files protection and to change user’s habit in handling confidential information. \r 2. Procedures\r “CryptoDefender” is an add-in for common application software, e.g. Word, Excel, etc. It will appear as a new tab in the ribbon which provides the software an alternative for saving and opening a file. It protects the files in two ways: encryption and steganography. The data is first encrypted into cipher text as these encrypted data will be hidden in an image file to lower suspicion of readers. All of these procedures will be done by one click. For encrypt and decrypt, the user just needs to click the “Protect” and “Decrypt”. An extremely fast way to encrypt the file is “Quick Protect”. It will randomly choose an image from the image folder according to their file size. This function saves the time for choosing an image.\r 3. Data\r The method for steganography is using last two bit of R, last three bit of G and B to store the encrypted data. In 24-bit bitmap, RGB is represented the color of each pixel and each of them is 8-bit. The leftmost bit of each byte contains the highest value, and the right one contains the lowest value. Therefore, any change in the rightmost byte will only cause a minimal change in a byte value, and the color as well. 2-3-3 method is adopted to replace the pixels as encrypted data. It is used because it is in coordination with the program’s fluency. 2-3-3 is obtained so that 1 pixel will contain 1 byte of encrypted data. For R, the last two bit will be replaced by encrypted data. For G and B, the last 3 bit will be replaced by encrypted data. If the Bitmap size is larger than the encrypted data, random data will be replaced into the remaining pixels.\r 4. Conclusion \r “CryptoDefender” is user-friendly and efficient way to protect important and confidential digital files on most personal computers. This software will help to change the user’s habit in securing their information as to avoid data leakage even when they are accidentally lost.

1. Purpose of research \r To investigate the feasibility of using municipal cellulosic wastes as feedstock for production of biochar in pyrolysis, the effects of metal catalysts in pyrolysis, and the applicability of the produced biochar as a fertilizer\r 2. Procedures \r A. Investigation into the characteristics of (metal catalyzed) pyrolysis of various cellulosic wastes \r 1. The cellulosic waste (and catalyst) was weighed and put into a boiling tube. The tube was stopped with a plastic bung with holes. A plastic tube and a thermocouple were inserted through the holes. The other end of the plastic tube was submerged. \r 2. A Bunsen flame was used to pyrolyse cellulosic waste. Temperature and time of reaction were recorded. Gas produced was collected underwater. Biochar and bio-oil were obtained and weighed. \r B. Evaluation of adsorptive capabilities of different materials \r 1. Blue light absorbances of KH2PO4 solutions (mixed with vanadate-molybdate reagent to form yellow solutions) at different concentrations were found and an absorbance-concentration curve was established. \r 2. 5g of each material being evaluated was sandwiched between two pieces of filter paper before being put into a suction funnel. KH2PO4 solution was poured into the funnels. The setups were left overnight and filtrates were collected. \r 3. Collected filtrates were mixed with vanadate-molybdate reagent. Concentration of phosphates in each filtrate was found by the curve.\r 3. Data \r I. Highest percentage conversion from waste to biochar: 94.1% (paper towel, iron wool) \r II. Highest sequestration rate of carbon: 98.6% (paper towel, zinc) \r III. Lowest pyrolysis temperature: 162°C (paper towel, copper) \r IV. Best catalyst in terms of speed of biochar production: copper (+47.7%) \r V. Highest speeds of biochar production (w/ and w/o catalyst): 46.4g/hr (paper towel, copper) and 27.7g/hr (sawdust) \r VI. Adsorptions of KH2PO4: 14.4% (biochar from sawdust)/ 9.02% (sawdust)\r 4. Conclusions \r The pyrolysis of cellulosic waste to biochar was achievable at school laboratory conditions, with satisfactory results in carbon sequestration, production speed and percentage conversion. \r Under catalysis by various metals, the production of either biochar or pyrolytic gas and oil can be optimized, providing a low-cost way to derive fuel and sequestration-ready carbon, both crucial as answers to looming crises. The use of copper greatly speeds up pyrolysis and lowers the pyrolysis temperature, further increasing the economic potential of the process. \r Biochar is also an effective means to soil management, as shown in field and laboratory experiments. Its adsorption capability far exceeds that of untreated cellulosic waste, retaining nutrients to be taken by plants instead of leaching away. It was also shown to improve fruit yield and induce ripeness in tomato, making it obvious that biochar is also a viable fertilizer. \r All in all, metal-catalyzed biochar production from municipal cellulosic waste and the subsequent use of biochar as fertilizer have the benefits of: low feedstock cost, low energy cost, fast production, carbon sequestration, soil management and waste recycling. It is a remedy to some of the most persistent and serious global problems: food and energy crisis, water pollution, excessive greenhouse effect alongside waste treatment.

This project aims to improve the quality of toilet hygiene. The product designed should fulfill the requirements of being an environmentally friendly, user friendly and economical toilet seat system which guarantees the safety and hygiene of the toilet. This project also aims to discover the efficiency of the toilet seat system in eliminating pathogens through conducting various experiments.\r In this project, the photocatalytic property of titanium dioxide is applied. When titanium dioxide is under exposure to ultraviolet radiation, they generate free radicals, which are efficient oxidizers of organic substances. Also, research has shown that the safest ultraviolet light used will be UVA. Thus, by using titanium dioxide paint under exposure to ultraviolet light to oxidize pathogens and toxins, the aims will be achieved. Other than that, experiments will be conducted to explore the efficiency of titanium dioxide under exposure to UV radiation in eliminating pathogens by counting the number of bacteria on the toilet seat system after different time intervals the seat system has been turned on.\r The procedure of constructing the product includes drafting the product, purchasing the appropriate apparatus and materials, constructing the prototype, and checking if the product fits the goals set. Lastly, improving the design based on the flaws found during the checking procedure, as well as checking the product to see if it fits the original goals set.\r The procedure of the experiments aimed to explore the efficiency of titanium dioxide under exposure to UV radiation in eliminating pathogens conducted includes\r counting the number of bacteria on the toilet seat system after different time intervals by inoculation of bacteria on the agar plates.\r Test results showed that the number of bacteria had a steady and notable decline after different time intervals. Results also showed that bacteria would be thoroughly terminated after the system had been turned on for at most one hour. The information was then used to set the delay timer to restrict the amount of time the ultraviolet lamp was turned on to save energy.\r Moreover, the toilet seat system has also been improved so that it will complete the automatic cleaning procedure even without the user lowering the toilet seat. This improvement was made so that the product could be more convenient to toilet users.\r The system also deodorizes the toilet as the oxidization of bacteria and organic substances reduces the putrid odor released by them when they carry out chemical reactions.\r In conclusion, the project succeeds in accomplishing the goals set and is capable of improving the quality of toilet hygiene, especially in common households. The project is also successful in finding out that the toilet seat system is efficient in eliminating pathogens.

Miracles in life originate from daily life itself. What can be imagined can really be achieved. Hong Kong, as an international city, is small in area and densely populated. To utilize space, tall buildings inevitably emerge. Taking elevators has therefore become the daily routine of everyone of us. However, problems abound with the present elevator system. You have probably gone through the dreadful episode of waiting long for an elevator to come, and passage being interrupted by unreasonably frequent stops. Besides, it wastes space, since each elevator tube can only accommodate one elevator. This is why our Free-D Elevator System will revolutionize the present one. It consists of a large cylindrical tube, which can be divided into several smaller, imaginary sector-shaped tubes. In each small tube a large number of elevators move vertically by magnetic levitation. The elevators can also rotate from one tube to another, thereby avoiding collision. This innovative design will substantially increase the number of available elevators for given space. Most importantly, it is highly feasible.

In the future, energy supply is the most serious problem to our society due to the shortage of fossil fuel. We should try to save energy as much as we can in different aspects in order to maintain the sustainable development of our society. According to the statistic report of electrical end uses 2008, showing that Space conditioning and Lighting shared 27% and 12% of the total electricity supply respectively. We design this “Free-Dome” to provide the individual users unique spaces for their work or entertainment where the lighting and temperature are easily and freely controllable. As a result, we may save lots of energy by reducing the lighting and space conditioning to the unnecessary area or public area.

a. Purpose of the Research Nowadays people are getting unhealthy, especially the heart. Since the outbreak of SARS, the Hong Kong citizens cared more about their health. In the past two decades, due to the technological advancement, many medical instruments that were used by doctors are now available to the public. One of the examples is the sphygmomanometer used for measuring blood pressure. On the other hand, very few heart monitoring devices are developed for public use. As a result, there is a need that such heart monitors should be available to the public. b. The device Our device is a modified stethoscope, which electronic components are added to this common medical instrument. The device mainly consists of 3 parts: 1. The sensor: modified from ordinary stethoscope, which a condenser microphone is added to change the heart sounds into electrical signals 2. The signal processor: integrated circuits and resistor-capacitor couples, which the cost is much lower than digital electronic components, are used to amplify and filter the noise in the electrical signals. The processor is divided into 3 stages: - Preamplifier: Amplifies the electrical signals converted from heart sounds - Low pass filter: Filters the noise in the signal. The cut-off frequency is 600Hz, which most of the heart sounds are below 600Hz. - Power amplifier: Amplifies the filtered signals before outputting into computers or earphones. 3. The output devices: it can be a computer or an earphone. In a computer, the heart sounds can be converted into graphs, enabling precise graphical analysis. Since many abnormal heart conditions will alter the heart sounds, with the aid of computers and graphs, people can know whether their hearts are normal or not, and can seek for medical support before developing any critical situation. Moreover, abnormal heart sounds are more significant in graphs, so any heart problems can be discovered more easily. c. Data During an exhibition in Hong Kong, about 1000 people tried the device. Among them approximately 150 people were confirmed to have heart problems with abnormal heart sounds. Using our device, we discovered 109 of them. As a result, the accuracy of the device is about 72.6% d. Conclusion With the low cost of our device (~€9.80/US$12.80), everyone would be able to afford it. As a result, people can check their conditions of their hearts more frequently, and would be able to discover any early heart problems.

One afternoon, a photography enthusiast, Mr. Cheung was holding some photos, completely absorbed in the fond (but ancient) memories of his honeymoon in Cairo. The badly-yellowed photo prints reminded him of every sweet and romantic moment of the “good old days”. He was soon rudely awakened when Mrs. Cheung shouted, “Honey dear! I was told that high-tech is ‘in’, and the single-lens reflex camera is totally out! So stop hugging the old out-dated pictures.” Mr. Cheung fired back, “Oh, you know nothing. This is something you cannot replace at all, and my camera is a classic.” Smiling at him, Mrs. Cheung took out a new gadget, “Right, right, now calm down. It never hurts to have both worlds. Look what I’ve got you. This is called ‘Stereoscopic Camera Lens’. Its little coloured spectacles can capture everything, say, the sensational Great Pyramid, in three dimensions!” As we are asking for and relying more on technological advances, the Stereoscopic Camera lens and the Stereoscopic Magic Box are surely innovations that promise to add a new dimension to our lives. Surprisingly, the working of these two gadgets involve only some simple scientific theories such as polarization, doping and anaglyph; and employs the special property of Liquid Crystal Layer (LCD) under electric current. Stereoscopic photos can now be easily available to us. Both of our designs, the Stereoscopic Camera Lens and the Stereoscopic Magic Box, can turn something ordinary into extraordinary by making plain, 2-dimensional things ‘stand out’ before your eyes. The Lens itself is crafted with such precision that it can capture any image both faithfully and flawlessly. The Magic Box uses electric current to catalyze and enhance the 3-dimensional transformation. So each picture is vibrant and true-to-life. The Lens and the Magic Box will certainly revolutionize our vision of things around us. To enable you to have a good understanding of the theories behind the making of the Stereoscopic Camera Lens and the Stereoscopic Magic Box, we have made simple models of them with prisms, and they are in display at our booth. Anyone who is interested in these fancy gadgets should definitely come to our booth to experience a new view of the world!