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Mathematical Analysis of Root Growth in Gamma-irradiated

Root growth is related to the acquisition, distribution, and consumption of water and nutrients of plants. As a vital organ, roots directly take the effect of environmental change and its behavior is closely related to the growth of the whole plant. With such, the importance of root systems has motivated botanists to seek a better understanding of root branching complexity. This complexity, which has been difficult to comprehend using simple Euclidean methods (i.e. lines and circles), is important to the survival of plants, especially when the distribution of resources in the environment is scarce. Mathematical models using fractals and computers can be applied to accurately understand the growth and form complexity of plant root systems. This study was conducted to analyze the root growth of gamma-irradiated cashew and mangosteen using fractals.

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Cable Stripper

PURPOSE OF THE RESEARCH \r The purpose of this project is to provide a cost-effective and efficient way of \r stripping electrical conductors, with thicknesses of 16mm up to 70mm in diameter, \r of their isolation. The current methods that are available are unsafe and unpractical. \r Therefore this project determines a safe way of stripping cables and also provides a \r new product to improve the worker’s safety during the process of stripping cables. \r PROCEDURES \r The solution can be found by doing research on the types of cable isolations \r currently on the market. By talking to the workers who use these types of tools, and \r strip these types of cables on a daily basis, I can comprehend the problems posed by \r the present methods and provide a solution. \r DATA \r An electrical cable is commonly a conductive wire surrounded by a nonconductive, \r insulation sleeve. In order to splice two cables together or connect the \r cable to an electrical device, the conductive wire inside the sleeve needs to be \r exposed. \r Numerous tools have been developed for slitting and stripping the electrical \r cable in order to expose the said conductive wire. The simplest tool is a knife with \r which the user makes an annular cut in the sheathing. The end portion of the \r sheathing then is pulled away exposing the individually insulated wires and the bare \r ground wire. The knife may also be used to cut away a short portion of the \r insulation at the ends of the wires. During both operations the user has to be \r extremely careful, or else the knife blade may damage the insulation around the \r internal wires and even nick the conductor or he may injure himself. To do so the \r user must first cut away several inches of the plastic sheathing at the end of the \r cable. A short length of the insulation then is removed from around each end of the \r conductors. \r As an alternative to using a knife, various scissors-like wire strippers have been \r developed. Although such scissors-like wire strippers are effective for removing the \r insulation from individual wires within an electrical cable, they are not efficient for \r removing the sheathing from the end of the cable in order to expose the individually \r insulated wires. \r A disadvantage of using a conventional knife and with using the known wire \r stripper is that a cable having a relatively thick insulation sleeve is difficult to strip \r and thus prepare for connections, since conventional wire stripping tools and other \r conventional devices, such as knives or tools with enclosed blades are inefficient for \r stripping thicker cable jackets. \r A further disadvantage of the known wire strippers is that, its basic \r characteristic dictates that the degree of friction between the tool and the wire after \r the insulation has been ringed will be high. This occasions no particular difficulty \r when only a short length of insulation is to be removed from the end of the wire. \r However, when yards and yards of insulation are to be stripped, as may be the case \r when reel ends are to be prepared for scrapping, the conventional wire stripper \r generates so much friction that it cannot be efficiently utilised. \r CONCLUSION \r The developed product enables workers to effectively strip electrical \r conductors without any impeding danger to themselves or the risk of damaging said \r cable. It is cost-effective and saves a lot of time. After several tests of the product no \r problems have been encountered up to this point.

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Charging the Miniature Electronic Components of Medical Equipment in Vivo

世界上有許多病患,需要在體內植入電子醫療裝置,才能維持生命。然而,電池充電的問題卻一直無法克服,於是必須透過開刀重新更換電池,如此不僅增加病患的痛苦,也增加了醫療成本與環保問題。然而,過去研究以提高電池蓄電量為主,只有極少數研究著重在探討隔空充電技術,例如:動物體內電池充電。本研究主要是應用電磁感應原理,設計一套可以針對實驗兔體內體溫發射器的電池進行充電的方法,及探討充電過程所產生的電磁輻射及其影響。我們的初步研究成果顯示: (一)將24V與18V兩種電壓分別輸入電磁棒,在實驗兔動物身體表面進行充電,發現可產生的最高充電電壓值分別為4.75 V與3.64V。(二)充電30分鐘後可讓體溫發射器每二秒發射一次訊號,為期長達8天。(三) 將24V與18V兩種電壓分別輸入電磁棒,在距離電磁棒5-60cm的範圍,最大的電磁輻射值為179.6mG及0.1 mG。本研究證實我們設計的電磁棒可以對兔子體內電池進行隔空充電,並且不會對實驗兔子造成電磁輻射傷害。我們建議未來可以應用此方法解決動物體內醫療電子元件的充電問題。

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討論顯微鏡下的化學反應

由於想了解化學反應的微觀形態,我們設計微型化學反應裝置來比較巨觀(傳統型)與微觀(創新型)化學反應間的差異,並探討其實用及環保方面的問題。在顯微鏡底下,我們觀察化學反應的沉澱結晶及電解反應,嘗試以各項變因(溫度、濃度、聲波…等)來觀察其結晶的型態。我們已成功地將實驗藥品用量減少到一滴(約0.04ml),並以微觀的角度觀察化學反應的過程。在實驗中,發現反應進行時,粒子會不斷流動,經查證後為愛因斯坦所提出的布朗運動,並且測得硫顆粒的直徑大小約4.2 ~ 6.7 微米。不同聲波所造成硫粒子的移動速率不同,而不同溫度的部份,我們發現→每增加十度硫粒子移動速率增加約兩倍。在面積4.392×10-4cm2 範圍內大約有250~300 顆硫沉澱的粒子。本實驗成功地將顯微鏡應用在化學領域上,若將此實驗推廣,可達到污染少、觀察實驗的時間短、用量少的目標。此實驗是邁向化學微觀世界,一種值得嘗試且創新的方法。In order to compare the differences between the chemical reactions of macroscopic reactor and microscopic reactor, we have designed a device of chemical reaction and researched into the problems of their environmental protections and practical aspects. Under the microscope, we observed not only their precipitating crystal compound from the chemical reaction and electrolytic reation but their types of crystal. We have successfully reduced the dose to one drop ( about 0.04ml) and observed the process of their chemical reaction from the angle of microscopic reactor. During performing the experiment, we found the particles would keep flowing while the reaction was working. It was proved as "Brown motion" introduced by Einstein. The diameter of these particles were around 4.2~6.7μm. We find that different sound waves and temperatures,the motion speeds are quite different. And the movement rate increases about two times as the sulfer particles increase 10℃ each time .Within the measure of area of 4.392×10-4cm2,there are 250~300 sulfer particles.The experiment has successfully used a microscope in the field of chemistry. If we popularize the experiment, we can reach the goal of less pollution, fewer the dose and time-saving observation. It’s an innovation to step to the world of chemical microscope world.

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就是那道光-色素增感型太陽能電池改良之探討

在這能源短缺的時代,開發替代能源已經成為主要課題。利用光觸媒特性所製成的色素增感型太陽能電池,因二氧化鈦光觸媒受到紫外光照射才產生電子躍遷,吸收光的頻率區域狹小,實用性不高。因此研究氧化鋅、二氧化錫與二氧化鈦混合,是否能提升該電池的轉換效率。藉由各種變因的探討,從中選取最有利的方式,使太陽能電池發揮更大的效益。除了以溫度、電解質、混合比例等因素外,增加電極面積以及串聯均可提高電壓與電流,以增加日常生活的實用性。如不斷的改進發展,諸如電解水、使小燈泡發光,甚至各種小家電用品的使用,都可應用於其中。In times of energy shortage, exploring the alternative energy has already become a main issue. The dye solar photocell is using photocatalyst characteristic. Because the electron transition is caused by lighting up the titanium dioxide photocatalyst by the ultraviolet, the frequency of spectrum is narrow and small. It is thus impractical. Therefore, we research whether or not the mixtures of zinc oxidize and tin oxide with titanium dioxide can improve the conversion efficiency of the dye solar photocell. Through discussion on various kinds of factors, we can choose the best way to make the dye solar cell yield more efficiency. In addition to the factors such as temperature, electrolyte, mixed proportion, etc., increasing the area of electrodes and contact can improve the voltage and electric current. That way we can increase the practicability for daily use. With constant improvement, it can be applied to many kinds of things, such as electrolyzing water, small bulb lights, even small household appliances.

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Study Biological Deoderization using Bacteria in Rumen of Ostrich

Although it is well known that, unlike the feces of a fowl, those of an ostrich\r do not produce foul smell, the impact of different enterobacteria on elimination of malodorous\r substances has not been seriously investigated. I sought to test the hypothesis that ostrich\r enterobacteria (OE) are useful to eliminate hydrogen sulfide (H2S) and ammonia (NH3), two\r important components of foul smell of the feces.

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Energy-Transformation Railway System

There are numerous problems caused by today's railway system. This makes Hong Kong a less attractive place to live in. We have to tackle these problems in order to make Hong Kong a better place. Our model can recycle the energy dissipated in the rail vibration, reuse the sound energy produced by the wheels and the rail by a sound energy conversion system, recycle the wind power in the tunnel by a new type of wind turbine, the Wind Power Generator Underground (WPGU), recycle the thermal energy produced by the air-conditioning system of railway stations by a new system, the Thermal Energy Conversion (TEC). When the rail is bent, the magnets attached to it are also pulled down. When the rail returns to its original position, the magnets attached to it are pulled out of the coils. In both cases, the magnets move against a force. The work done to move the magnets against the force is converted to electrical energy. Also, the bottom of the MTR is designed to be curved. The sound waves produced by the contact point of the wheels and the rail directing towards the bottom of the MTR would be reflected to an elastic material which has a number of magnets attached to it and corresponding number of solenoids are fixed on the ground below the magnets. Sound energy can be converted to electrical energy in this case. When a train approaches or passes through the section that the WPGU is installed, wind is generated. The wind forces the wind turbine to rotate at a certain high speed. The turbine transmits the rotation to the coils in the dynamo, and hence electricity is generated. Heat released from the air-conditioner is absorbed by water. The hot water is then pumped into the system. As the hot water in the pipe flows through the evaporator, liquid ammonia inside will evaporate and flow into the electricity generator. Inside the electricity generator, the gas will push the turbine to rotate and hence electricity is generated. The ammonia gas is then condensed in the condenser and flows back to the evaporator. Hence ammonia is used circularly. In order to explain our principle, we would like to introduce the Lenz's Law, an induced current flows in such a direction as to oppose the movement that started it, the Faraday's Law of electromagnetic induction, the induced electromotive force in a circuit is equal to the rate of change of magnetic flux through that circuit, the Law of Conservation of Energy, energy can neither be created nor destroyed, but can transform from one form to the other.

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Giving Bugs the Chop !

The purpose of the research was to find out if Manuka oil (an oil with natural healing properties which is extracted from the NZ Manuka plant, Leptospermum scoparium) could be used to reduce the populations of bacteria and fungi that build up on chopping boards used in the kitchen for food preparation. If it were effective, then it would reduce the risks of microbial contamination of foods prepared using the boards.

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巴斯卡正方形

本文將一道組合問題可能的方法數製成正方形表格,以「巴斯卡正方形」命名。將此正方形內的組合數同餘若干自然數後,觀察及歸納其結果。 同餘後不同的餘數配予不同顏色,產生一些特別的圖形,例如:「教大中庭系列」及「棋盤格系列」。我們研究了這些圖形的規律性以及對各個餘數的個數進行計數。 我們利用Lucas’s Theorem及(1+x)n 展開的係數搭配乘法原理來做計數的工具,並且研發了一個算式用於計算任意組合數被質數的次方同餘後的結果。

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Habit and comparison of the Opistophthalmus pugnax and the Opistophthalmus

To compare the habitat and physical\r differences of two burrowing scorpions, Opistophthalmus pugnax and\r the Opistophthalmus glabrifrons to be found in the Gauteng area\r (South Africa). Although these scorpions’ habitat overlaps, they don’t\r co-occur at the same site.

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還我無水污染的顯微電解世界

Chemistry experiments in school produce an abundance of waste in both materials and equipment. Since hands-on experimentation is a critical pedagogical tool the trend in classroom experimentation is clearly towards environmentally friendly experiments that scale, but was also able to measure reaction rate in blue cupric sulfate solution using the color dissipation as a rate gauge. There was an evolution of apparatus and experiment design beginning with simple magnifying glass optics and advancing to a custom made, light-gathering microscope video apparatus that allows the experiment to be monitored and files recorded for later viewing. I was inspired by the Yin Yang Sea phenomenon in Taipei County. The Yin Yang Sea is a coastal area in Chinkuashih, Taipei County where coastal currents in the area lack the strength to disperse the heavy metal pollutants that empty into the Lientung Bay. The result is a contrast between the blue sea water and the turgid yellow ground water. This contrast led me to add an all-purpose indicator to the reactant solution. This deepens the visual effect of the electrolysis experiment. 我們從環境保護的角度去思考學校的化學實驗時,減量減廢的微型化學實驗已是未來實驗的趨勢。經過多年的努力,我除了成功的做到電解最微量的一滴溶液外,對於從藍色硫酸銅溶液顏色消失的電解時間裡,還可做定量的檢定感到不可思議!為了更清楚看到液滴溶液的電解反應,儀器的設計由放大鏡到自組顯微投影機,最後進階到顯微視訊的畫面,它不但可記錄下來,而且可在電腦中播放。為了更清楚看到液滴溶液的氧化還原反應和酸鹼變化,我想到了在北台灣的金瓜石海域一處特別的景觀,那就是離岸近海處有黃藍兩個不同顏色的陰陽海!於是我加了廣用指示劑到液滴中,由電解後出現的的陰陽海畫面,更可加深實驗的效果。 最重要的是:最環保也最接近零污染的顯微化學實驗,已然是未來可發展下去的目標。

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超聲波應用之研究

在實驗用共振法測量聲音在固體、液體、氣體中的駐波聲場,測量各介質中的聲速。研究超聲波在液體中的空腔效應,鋁箔在不同液體受空腔效應所破損面積與時間略成正比,並發現在水與各濃度的洗潔精水溶液中以水的破損效果最明顯。另外利用1.65MHz 高頻超聲波打入水中,因駐波使水有疏密不同產生狹縫,以雷射通過狹縫有光的繞射花紋產生,由干涉條紋可推估駐波波長。利用閃頻共振法研究光彈材料超聲波場,且發展出以肉眼觀測的裝置,由光彈材料的花紋級數與應力研究中,發現花紋級數與應力成正相關,由聲場中的花紋顏色判斷所受應力大小,並發現超聲波不僅有聲場產生並伴隨熱效應,會影響觀測花紋級數。This project began by studying the fundamental properties of acoustic waves, the relationship between its velocity, frequency and wavelength. Experiments regarding the distribution of sound waves in different mediums, and the induction of resonance in solid, liquid and gaseous materials were conducted. Results from utilizing suspending method to confirm theoretical prediction of sound velocity was accurate, and the sound wave patterns in photo-elastic materials were observed. It was also observed that an aluminum foil would be cut in an ultrasonic cleaning device. The effects of different liquids such as water and detergents on cleaning effectiveness were then experimentally determined, taking into account factors such as viscosity. From reference materials, we learned that ultrasonic waves would create Caritation in liquids. Traditionally, sound waves are expected to exhibit only longitudinal waves, yet in this study it was discovered that the residual\r stresses from resonance in photo-elastic materials also indicate the existence of transverse waves.

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