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標好標滿

探討平面上n條直線,每兩條相交出一個交點,但不三線共點,並在每個交點上標上數字1至n-1,使任何一條直線上恰好出現1至n-1各一次。得到奇數條直線無法、偶數條直線可以。 推廣至三維空間,探討n個平面,每三個相交出一個交點,但不四面共點,發現到三維空間有兩種推廣方式: 一、在每個交點上標上數字,使每條直線上的數字都不重複 二、在每個交點上標上數字,使每個平面上的數字都不重複 在此兩種情況下,可見當有三個平面時皆可以。 探討第二種推廣後發現在六個平面時亦可以給出構造。而後又發現其等價於Baranyai's theorem故得到平面個數為三的倍數皆可以,再根據文獻構造出三維度空間9個平面的一種方法。

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Sustainable Graphene Oxide Support for Ruthenium Catalysts to Improve the Efficiency of the Hydrodesulfurization of Thiophenes

沙烏地阿拉伯 is the largest oil exporter in the world. 64,000,000 tons of sulfur oxides are produced every year through the combustion of organic sulfur compounds in the oil industry. This leads to several environmentally serious problems, including air pollution. This research provides a novel strategy to utilize natural-based Graphene Oxide (GO) as a support for ruthenium (Ru/GO) to functionalize as a green catalyst for hydrodesulfurization. Physical activation of camel bone samples was carried out by carbonizing them at 500oC to produce camel bone charcoal. Modified hammer’s method was employed for GO production, followed by doping of ruthenium in a simple synthesis step. The prepared catalyst has been characterized by XRD, SEM and EDX techniques. Thiophene and 3-methylthiophene were used as model compounds in the hydrodesulfurization process. The catalytic reactions were carried out at atmospheric pressure in a continuous up-flow fixed-bed quartz reactor. The composition of the sulfur containing gaseous products was analyzed by gas chromatography. The product distribution achieved for thiophene was 3-6% butadiene and 76-77% butane. And for 3-methylthiophene, it was 32.3% of pentaned 1-pentene and 2-pentene and the selectivity percentage was 45%. Ru/GO has been found to be an excellent catalyst of thiophene and 3- methylthiophene hydrodesulfurization and is a considerable improvement when compared to the commercially available catalysts. The prepared catalyst shall potentially lead to the reduction of sulfur pollution in the future. The positive effect on the environment could be substantial.

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會隱身術的平方公分

探討原正方形經拼湊組合成的長方形面積會減少一平方公分可能的原因,另外,由角度與相似三角形邊長與邊長比值相等的原理來觀察。實際上由於原正方形切割成兩小角形,及兩梯形後,小三角形與梯形組合後並未成為一大三角形,以致於全部組合後,有面積重疊的地方。我們推論出的公式:原正方形邊長甲,切割長度乙,則面積差量 =拼湊後長方形的面積-原正方形的面積=〔(2 × 甲-乙)×(甲-乙)〕-(甲 × 甲)。而我們發現.任一正方形邊長甲都可以找到一最佳切割比例,及長度乙≦甲/2,且以最接近甲/2 的長度時,使得拼成後的長方形面積與原正方形面積的差量為最小,並可將拼成後的長方形歸類為凸出型(以⊕表示)與凹陷型(以Θ表示)兩種類型:最後我們歸納出一規則,即相同面積差量的每一列中的每一數恰好是前兩數的和(最前面兩數除外),也就是說,對每一列數任取連續三數(A,B,C)就是一組最佳組合,C 為正方形邊長甲,A 為切割比例乙,而面積差量=B×(2B-A)-C×C=B×(B+C)-C×C 最小。另外,亦可連續四數為一組合(A、B、C、D), D 即為組合後長方形長,B 為寬,因此面積最小差量為:B×(B+C)-C×C=B×D-C×C,可用來預測出不同的正方形邊長甲,它們所得到的面積最小差量相同的最佳切割值。.另外,我們可以面積差量=1(如底色為黃色那一列)正方形邊長為依據,我們將其面積差量=1 的正方形邊長甲×倍數,即可預測得到最小面積差量=倍數×倍數。反之,我們亦能根據面積差量最小值所分解成平方數a× a(倍數×倍數),預測得到最佳正方形邊長=如底色為黃色那一列正方形邊長甲×a(倍數)。同時,經由我們整理出的規則,預測面積差量為平方倍之正方形邊長,並依據面積差量=1 的正方形邊長,來預測得到長度為倍數之最佳正方形邊長的凹凸類型

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A Backpropagation Neural Network Model on Precipitation Forecasting in the Philippines

Backpropagation neural networks were used to forecast daily rainfall with minimal error for Metro Manila in order to have an inexpensive way of accurately predicting weather. Calamities brought on by heavy rainfall have caused great economic, infrastructure and human loses. Neural networks have the ability to discern complex patterns in noisy data; this makes it a viable method for weather forecasting. Daily precipitation, humidity, rain indication, sea level pressure, temperature and maximum sustained wind speed for January 2000 to December 2010 were acquired from the Philippine Atmospheric Geophysical and Astrological Services Administration. The neural network made use of Python 2.7.2 and the backpropagation program by Neil Schemenauer (python.org). It considered different neural network architectures with a total of 2844 data sets for training and 708 data sets for testing. Each neural network’s accuracy was measured with a graph of the actual and predicted values, correlation coefficient, and root mean square error. It was observed that the neural network with architecture 5-8-1 yielded the most accurate results as it had the highest correlation coefficient of 0.48599 and smallest root mean square error of 14.84. It was also observed that the trends of the predicted values followed that of the target values. This suggests that it is possible to create a neural network with a moderate correlation given daily weather data. It is recommended that further researches make use of hourly data instead of daily data for more accurate results. Other variables, which might affect rainfall, not in this study should also be considered. This research could aid in the anticipation of calamities and the decision making involved in shipping, fishing and aviation industries.

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Neolema ogloblini- An agent in the biological control of Tradescantia

Tradescantia (Tradescantia fluminensis) is the worst weed in New Zealand. By smothering and shading out seedlings, Tradescantia prevents forest regeneration. Current control methods are ineffective and simultaneously cause harm to native forest. In 2011 Neolema ogloblini, a Brazilian beetle was introduced into New Zealand as a biological control for Tradescantia. To be successful in New Zealand, a country with different environmental factors, the beetles’ ranges of preference (temperature and light intensity) had to be investigated. A gender specific trait also identified, to enable desired sex ratios within founding populations to be selected. [18] This would ensure that the beetles are not released in areas of physiological stress, and can be optimised to have the greatest impact on Tradscantia. To establish how the intensity of light affects the distribution and amount of Tradescantia eaten by N.ogloblini a choice chamber investigation was conducted. Different layers of shade cloth provided a range of light intensities 150-3450Lux (likely to be found under forest canopy where Tradescantia is problematic). Thirty beetles of a range of sizes and approximately same maturity were randomly distributed through the chambers. Each chamber contained a shoot of Tradescantia with 5 leaves. After a 24hour period the number of beetles in each chamber were counted and the amount of surface area of the leaves eaten measured. The effect of temperature on the amount of leaf surface area eaten was investigated by selecting 90 beetles of a range of sizes and withholding food for 24hours. Five beetles were placed in each of three containers containing two leaves. Each trial container was precooled/warmed to the test temperature before the beetles were added. Leaves of a similar size, shape, mass and maturity were used. All leaves were genetically identical and collected from the same location. Sets of three containers were held in the dark at the following temperatures for 24hours: 9°C, 15°C, 20°C, 25°C, 30°C and 35°C. The surface area of leaf eaten at each temperature (mm2) was calculated. Lastly, microscopic dissections were conducted, using 32 beetles ranging in size, to establish if length (measured from the top of the head to the base of the abdomen) could be used as a phenotypic marker to identify beetle gender. While only a very weak positive relationship between increasing light intensity and the number of beetles was found a significantly higher area of leaf was eaten at a light intensity of 3450Lux compared to 150Lux. The amount of leaf area eaten is significantly reduced at temperatures of 15˚C and below, and significantly increased at 35˚C. There is no significant difference in the amount of leaf area eaten when comparing temperatures between 20-30˚C. Females have on average a larger body length (median=4.92mm) than the males (median=4.215mm). Therefore, sites with warmer temperatures in dappled light conditions (3450Lux) should be prioritised for the release of N.ogloblini, as this is the location in New Zealand at which their use as a biological control will be optimised. Beetle length can be confidently used to select desired gender ratios.

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VERMICOMPOSTING-EFFICIENT DAIRY SLUDGE MANAGEMENT

The continued growth of dairy farming in NZ and the move toward keeping cows on stand-off pads has seen a major increase in two significant waste streams, the wood fibre that is scrapped off the surface of the standing pads and the effluent that is now concentrated at the site of these pads. In combination these waste streams offer the farmer an opportunity to recycle valuable nutrients back into the soil as an up-valued soil conditioner. This investigation explores vermicomposting as a tool to efficiently manage these two significant waste streams. Sludge was removed from a settling pond and mixed with a range of carbon products that are recommended by Dairy NZ for use in stand-off pads: wood chips, post peeling, sawdust and also wood shavings (used in calf sheds). The wood fibre/sludge mixtures were assessed on their acceptability to tiger worms (Eisenia fetida) by measuring the pH of the mixture and seeing if they corresponded with the preferred pH for tiger worms. The vertical spatial distribution of tiger worms was measured over a period of 15 days and the rate at which the worms moved into the different mixtures was assessed. The worm mass before and after this 15 day period was also measured to ascertain the mixtures’ ability to support worm growth. Finally, different ratios of sludge and post peelings removed from a calf shed were used in a choice chamber experiment to establish the worms’ preference. Tiger worms were used throughout the investigation as they represent the worm species most widely used in vermicomposting in New Zealand. Tiger worms feed on decomposing organic matter, bacteria and fungi in the upper organic horizon of soil. All of the unused wood fibre and dairy sludge tested lay within the acceptable pH range for tiger worms. Wood fibre exposed to large amounts of urine ie calf shed post peelings, that lie outside the acceptable range can be favourably adjusted with the addition of dairy sludge. All the particle sizes of the wood fibre tested were found to be acceptable to tiger worms and capable of supporting increase in their body mass beyond that of the compost. Due to the observation that the worms did not integrate themselves as fully in sawdust as the other fibres tested it is recommended that further investigation should be carried out before sawdust is used for vermicomposting. While a comparison of the average worm density in each mixture may indicate a preference for post peelings this cannot be statistically proven and more trials are recommended. The preferred ratio within the limits that were tested is 1:3 calf shed post peelings to sludge (41% dry weight). Vermicomposting can therefore be recommended as a possible onsite technology to process the twin waste streams of wood fibre and effluent generated by dairy farms. The next step would be to implement medium scale field trials with a continuous windrow system, testing resulting compost for its nutrient content and then comparing this output to that of current practises

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A New Generation Colorimetric Method for Lead Analysis: APTAMER MODIFIED GOLD NANOPARTICLES

Lead is a toxic element which is used in the production of chemicals, dyes, accumulators and various industrial areas. It may cause complications even extended to death when it is taken consistently in high amounts. Lead poisoning is in the first place among the occupational diseases. It is gaining importance to develop new and sensitive methods for lead analysis. Because lead poisoning can progress without any symptoms and poisoning level (10µg/dL) is low. Disadvantages of the systems used for lead analysis are such as longer detection time, being expensive and difficult to implement. The aim of this project is to develop a new generation method in order to detect lead in blood, based on aptamer modified gold nanoparticles. We detected the lead in terms of color change obtained in gold nanoparticle solutions, with composite biochemosensor that is prepared with 20 & 80 nm sized gold nanoparticles and TBA(Thrombin Binding Aptamer). While immobilizing TBA to the gold nanoparticles, we benefitted from the magnificent surface affinity of the –SH (Thiol) groups that modified to the TBA. Gold nanoparticles that are used in development of our biotechnological method do not stimulate the immune system. The preparation of aptamers in completely sterile medium provides us to use our system in the lead detection of blood. Our method can also be used in the lead detection of mediums such as waste water, food and soil. We have developed a biochemosensor that can be used to detect the presence and absence of Pb2+ by taking into consideration the toxic effect in the human body. Also we detected the presence of lead colorimetrically, in low concentration levels and wide interval values of 4.4 – 11 µg/dL. The developed system is first that; it provides TBA to be used with its complimentary sequence detects the presence of lead colorimetrically and can be used in physiological media such as blood. Also our system can detect lead in amounts that are lower than the poisoning threshold.

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A Novel Spectroscopic-Chemical Sensor Using Photonic Crystals

Detection of harmful chemicals used in industrial complexes is crucial in order to create a safer environment for the workers. Presently, most chemical detectors used in workplaces are expensive, inefficient, and cumbersome. In order to address these deficiencies, a novel sensor was fabricated to produce a unique spectroscopic fingerprint for various toxic chemicals. The sensor was fabricated by depositing several layers of silica spheres (diameter ~250 nm) on a glass substrate using evaporation-based self assembly. As the spheres assemble to form a photonic crystal, they also create void (i.e., air) spaces in between them. Once the spheres assemble as a photonic crystal, a spectrometer was used to monitor the reflectivity. The spectrum had a high reflectivity at a specific wavelength, which is governed by the average index of refraction between the spheres and the void spaces. As a foreign chemical infiltrates into the photonic crystal, it occupies the void space, which results in an increase of the average index of refraction of the structure. Consequently, the peak wavelength of the reflectivity spectrum red-shifts, which then confirms the presence of a foreign substance. While the as-grown photonic crystal is able to detect chemicals, it is unable to differentiate between chemicals that have similar indices of refraction, such as ethanol and methanol. In order to detect chemicals with similar indices of refraction, five pieces of a single photonic crystal (i.e. five pixel device) were exposed to different silanes, which changed the surface chemistry of the silica spheres in the photonic crystal. In turn, the five pixel device was able to produce a unique chemical fingerprint for several chemicals, which can be calibrated to detect toxins in the workplace.

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Development of a compact, self-stabilizing handheld camera mount

My purpose of the Research was build a small, compact device for the GoPro, which minimizes shocks that are typically caused by running and makes the video stable. The device must fit into a backpack and must be designed for the GoPro. This scenario raised two central questions for me: Which laws of physics are used for the stabilization of the camera? How can those laws of physics constructively be transformed into a working device? I have built four prototypes. To know which prototype was the best, I compared them and gained data into diagrams. The result with the last prototype was very impressive and encouraging, whether your are walking, running or skiing, the videos were no longer shaky. My final prototype consisted of a hollow tube which extended vertically. My conclusions: First the handheld camera mount mustn't be too light, as the inertia of the device is too low. Second it mustn't be too heavy, because you normally have to hold it over a certain time interval. Inertia as well as lever principal were essential to produce a smooth video. The most difficult part to build was the fully gimbaled suspension because it requires as little friction as possible and it must be precise and solid.

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Robotic Window Cleaner

My project is a robot designed to clean windows and eliminate the need for human labor. My ultimate aim for this project is to develop my robot to clean high-rise buildings as well as homes. The current version of my robot is designed to clean only house windows. The idea to invent a robot that would automatically clean windows came to me when I arrived home from school one day and found my father struggling to clean the outside of our living room windows because he suffers from back and knee pain. During my research I stumbled upon high-rise window cleaning accidents in which people have lost their lives and this gave my project greater purpose. The major challenge I faced when designing my robot was getting my robot to stick to a vertical window while maneuvering around its surface without falling off. My solution was to use vacuum technologies, suction cups and direct current motors in my design. My robot is made up of a mechanical system, an electronic system and a pneumatic system. The mechanical system consists of direct current motors that drive the two arms of the robot backward and forward through a rack and pinion enabling movement. The pneumatic system provides the vacuum that enables my robot to stick to the window and also consists of pistons that lower the suction cups onto the glass. The electronics system is made up of a microcontroller that uses transistors to control the robots various components. Some key features of my robot include the new split unit design which includes a cleaning unit and a control panel that allows for a decrease in the weight of the device, ultrasonic distance sensors for window edge detection and a self drawing cleaning progress map which the robot displays on the LCD screen on the control panel. Gauges have been added to monitor pressure and vacuum levels in the system so that the user is aware if a problem were to occur. The dual squeegee design includes a squeegee on either end of the horizontal arm which are raised and lowered at certain times while the robot maneuvers across the window to result in the most effective clean. Attached to the squeegees are microfiber cleaning pads that are used to clean the window. I plan to one day develop my robot to clean high-rise buildings so it minimizes the risk of workers losing their lives.

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The Effect of Hands Free - Cell Phone Conversation on Visual Fields

It is a known fact that using a cell phone while driving can lead to reckless driving. According to research done by the World Health Organisation (2011) thousands of car accidents occur worldwide, each day, due to cell phone use whilst driving. Many of these car accidents result in serious injury or death of drivers, passengers or pedestrians. According to the Automobile Association (2012), cell phones are the number one cause of traffic accidents in South Africa. The high rate of car accidents due to cell phone use has led to legislation being passed, in most countries, banning hand-held cell phone use while driving. Hands-free phone equipment is not prohibited as it is widely regarded as a safe means of making and taking a phone call while behind the wheel. The purpose of this study was to show that the act of talking on a cell phone and not the method of talking (hand-held versus hands-free) increases accident probability. This study used a Friedman Visual field analyser which measures subject’s visual fields with and without engaging in hands-free cellular conversation. The results showed a significant constriction of the visual fields when subjects were conversing on a cell phone. These results were and can be explained by the fact that the test subject experiences cognitive distraction. Cognitive distraction occurs because the driver has to divide his/her attention between the cell phone conversation and the tasks relating to driving. These results have significant ramifications for road safety in a driving environment.

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永不妥協

本文籍由一套數學遊戲的必勝方法及其背後潛藏的數學原理,來作為研究目標。透過研究德國數學家E.Sperner 提出的方法所延伸的數學遊戲,來解決潘建強、邵慰慈兩位教授留下來沒有證完的遊戲結果[1],並將遊戲增廣至三維空間的探討且得到如下的結論: 一、平面棋盤 (1)不可換色,先下者恆勝,其最快獲勝方法,為依所下位置的三角形衍生子圖周界走。 (2)可換色,獲勝規則由棋盤的總頂點數決定,若棋盤的總頂點數為奇數,先下者獲勝;若棋盤的總頂點數為偶數,則後下者獲勝。 二、空間棋盤 (3) 不可換色,先下者恆勝,而最佳下法,則是下在大四面體本身內部的某一點,且其最快獲勝方法為,依正四面體稜邊所下位置走。 This study is mainly about an invincible method of a mathematical game and its theory from which it is derived. We want to solve the problems left by Professor Poon, K.K and Professor Shiu,W.C. and meanwhile extend it into three dimensions through the method brought up by E. Sperner[1]. On two dimensional case, the first player will win the game forever on condition that these two players can't change their chesses colors at will. And the fastest way to win will be just putting the chesses that along the baby triangle boundaries. If both players can change their chesses colors randomly, count the chesses number before starting the game. It is calculated that if the number of the total chesses is odd, the first player will win the game in normal and logical circumstances. On the contrary, if the number of total chesses is even, the latter will win. On three dimensional case, the first player will definitely win the game without allowing changing chesses colors. And the best strategy is putting chesses in the inner of the big tetrahedron; what’s more, going along the edge of the tetrahedron will be shortest way to win the game.

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