全國中小學科展

2003年

阻尼作用對搖擺系統的影響

地震波會以橫波和縱波的方式傳遞能量,學校的教學大樓中地下具有蓄水池者搖晃的持續性感覺比較短暫,於是利用彈簧波模擬地震波測試不同質量的台車接收到的能量會較空車為多。並利用自製模型測試不同容器形狀和水量的阻尼作用,結果發現搖擺時,時間球形>錐形台≒方形台;球形台裝有不同水量時擺動時間裝滿裝滿時>未裝水>裝1500mL 時;平行移動時則是球形台裝水2000mL 後鉛錘移動距離最短。整個實驗過程中由於未裝滿水的模型內部重心改變不規律,而且模型內所裝的水量因為不規則擾動經吸收的能量轉換成水溫上升的熱能,因此導致擺動能量的消耗造成擺動時間縮短,如果新式大樓興建時考慮消防蓄水池和水塔的造型和裝水容量,應可以減少地震時的搖晃時間,降低心理的緊張和物體因震動而產生的移動傷害。Seismic wave can transmit energy with transverse and longitudinal wave. The shaking of these buildings with reservoirs underground in our school for a shorter time, so we use spring wave to simulate seismic wave, and test the proportion of transmissible energy received from different mass of objects. The energy gets from wave motion passing on is bigger when cars carrying capacity than empty cars. And we use homemade models to test damped effect of different forms and water. At last we discover the time is Sphere > Taper ≒ Square while they swing with different amounts of water, the time it cost is Full > Non > 1500 mL. When they move horizontally, the plummet moved shortest, when the water of the sphere is 2000 mL. During the whole experiment, the center of gravity in the models, which are not full of water changes irregularly, and the water in the models can absorb heat energy from energy disturbing, so the swing of energy consuming makes the time of the swing shorter. If the fire controls reservoirs, the shapes and dress up water volume of the water towers, are taken into consideration, the duration of the shaking of earthquake will be shortened so that our fear and nervousness will be lessened, and the damage causer from the shaking will be reduced.

Waste Not,Want Not

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

Investigation on traditional medicine from plants in Namibia

My project is about investigation on traditional medicines in\r Namibia. This is all about plants and different herbs that different\r people in Namibia use for medicinal purposes. The objective of this\r project is to inform the world of how valuable nature is and how we can\r try to conserve nature’s treasure so that valuable knowledge cannot pass\r away with olden experienced herbalists. Understandably the enquiry\r into indigenous medicinal herbs arose from the need to expand the\r possibilities of ones own medical practice. It was very important for me\r to satisfy our farmer’s thirst for knowledge, which is what I want to do\r with the rest of the world.\r In this project I have included most but not all of the plants that we\r use in Namibia for medicinal purposes. Seeing that some of these plants\r do not grow in certain parts of the country, I have also tried to clone it in\r other parts of the country. I have also made a powder from one of the\r plant’s leaves and tested it on several people within the country.\r To conclude my findings and experiments I would like to say, let us\r try to take these precious knowledge left for us from our ancestors and\r maybe one day in the future we might need it in some ways.

初等代數鏡頭下的Fibonacci Sequence

壹、研究目的:培養建構式思考方式,提高解決問題的能力。 貳、研究過程:一先查數學辭典,確定F.S.之定義。二以文字敘述替代數字敘述F.S.,並分析歸納規律性。三將發表過的有關關係式,挑選適合以代數分析研究者,研究採逆命題角度處理,共有下列七種關係式採論之。 壹、Motivation and Purpose In this study, we expect to know something about Fibonacci Sequence (F.S.) that we can understand and enjoy as a high school student. 貳、Procedure 一.Make sure the definition of F.S. 二.Use algebra instead of numerical to state F.S. 三.Select the related formulas and discuss by fundamental algebra. We get 7 types as follows

棋子排列的平均值

本研究由下述問題開始:將n1 個黑色棋子和n2 個白色棋子排成一列,規定第一個棋子必為黑棋;對於每一種排列方法中,同色棋相鄰處記為1,異色棋相鄰處記為-1,所有1 和-1 的總和記為 t (n1,n2 )。對所有可能的排列方法所算出來的t( n1,n2 ) 值求其平均值,記為a (n1,n2 ) 。我們先由觀察各種n1 和n2 值,得到這平均值的可能公式,隨後並嚴格證明其正確性,證明方法也經過多次精鍊到十分簡潔的方式。以此為基礎,我們並做了各方向的推廣,研究涉及下列各點:(一) 利用組合數探討原來的問題。(二) 在第一個棋子不限定為黑棋的假設下,求平均值a( n1,n2 ) 。(三) 將棋子由兩種增加到多種。(四) 改變棋子排列以及相鄰的方式。經由研究,我們發現,每一次愈將問題推廣時,愈能找出清晰的概念涵蓋並印證先前的想法。Our study starts with the following problem. Suppose n1 black chesses and n2 white chesses are arranged in a line under the condition that the first chess is black. For any arrangement of these chesses, an adjacent pair of chesses having the same (respectively, different) colors is associated with a value of 1 (respectively, -1). Let t(n1,n2 ) denote the sum of these values. The purpose of this problem is to calculate the average value a (n1,n2 ) of these t (n1,n2 )which runs over all possible arrangements of the chesses described above. We begin from observing various values of n1 and n2 and find a possible formula for the solution. We then give a rigorous proof for the formula. After some refinements, simple proofs are also established. Based on this, we also make some generalizations. In summary, the research includes the following: 1. Study the problem by using binomial coefficients. 2. Calculate a(n1,n2 ) when t( n1,n2 ) runs over all possible arrangements in which the first chess can be black or white. 3. Increase the types of chesses from two to many. 4. Variant the arrangement method of the chesses from a line to other configurations. During the study, we find that whenever we extend the problem to a more general case, we make the ideas for the original problem clearer.

低溫二次燃料電池

本實驗係以台灣常見之數種植物(甘蔗、橡膠、破布子、苦苓)乾餾所成之多孔性碳棒鍍上銅和拷上Chitin 為電極兼電容,而以NaOH(aq)為電解液,製成化學電池。希望能研究出一低污染、低成本、能在常溫下經濟運作、並具有教學演示功能之電池。This research is based on the poromeric carbons which are made of several Taiwanese common plants (including: sugarcane, babul, Sabastan Plum Cordia [Cordia dichotoma Forst] , and Chinaberry tree [Melia azedadach L.]) by means of destructive distillation. The copperplating poromeric carbons later covered with Chitin functions as an electrode ac well as capacitance. Along with NaOH(aq) eletrolyte, a accumulator is then produced. The chief objective of this research is to produce a accumulator with low class of pollution and low cost, which is able to function economically under the normal atmospheric temperature. Also,this accumulator can serve as a teaching demonstration.

Ectomycorrhizal Inoculation of Anisoptera thurifera and Shorea guiso : GROWTH AND PHOSPHORUS DYNAMIC

Dipterocarps coming from Southeast Asia comprise about 53% of the world’s\r total exports of tropical hardwood products. However, the supply of dipterocarps is\r rapidly declining. The government is currently embarking on the establishment of\r dipterocarp plantations and encourages inoculation with ectomycorrhizal fungi to\r improve seedling growth and survival in degraded sites. Anisoptera thurifera (Blanco)\r Blume and Shorea guiso (Blanco) Blume rooted cuttings were inoculated with\r mycelial beads containing either Pisolithus PTG, Pisolithus H6394, or Astreus sp.\r Pisolithus PTG was collected from Acacia mangium stand in Malaysia, Pisolithus\r H6394 from Eucalyptus trees growing in a heavy metal contaminated area in New\r Caledonia, Astreus sp obtained from dipterocarp forest in Mt. Makiling, Philippines.\r The results showed that Astreus sp gave the highest root colonization (38%), height\r increment (86%), fine root (51%), coarse root (27%), shoot (43%) and total dry\r weight (40%) of A. thurifera over the control treatment. Astreus – inoculated plants\r had the highest shoot P uptake (41%) while PTG inoculated ones obtained the highest\r fine root P uptake (0.273 mg/root). The uninoculated plants had the lowest height\r increment, dry weight, and P uptake. In S. guiso, Pisolithus H6394, gave the highest\r increment (100%). Data were only obtained from four months of nursery experiments,\r hence, a longer nursery and field experiments should be conducted to achieve a\r complete evaluation of the physiological functions of ectomycorrhizal associations.\r Moreover, a wide range of ectomycorrhizal fungi associated with dipterocarps should\r be incorporated for selection of host compatibility.

SMS Link-Interactive

SMS.Link-INTERACTIVE is a system that facilitates the exchange\r of information between a central computer server and a remote cellular\r phone user, and allows remote modification of data in the computer\r through SMS. A cellular phone with a GSM modem is connected to the\r computer physically via a data cable. A program in the computer is\r notified whenever the cellular phone receives new messages, processes\r new messages by first authenticating the user’s identity, then checks for\r the information being asked for, as well as the changes that the user wants\r to be done. Information is then retrieved from a database in the computer\r and the appropriate changes are made. A message containing the\r requested information and a list of changes done is then sent to the user\r through SMS.\r Tests were made to get the speed of the system. Accuracy tests were\r done to determine if the program was able to ascertain the validity of the\r user correctly, return the requested data, and change the specified\r information.\r Using this system, doctors can access a patient’s data and change\r prescriptions; teachers can correct errors in grades; clubhouse personnel\r can add memberships; all these from a remote location by sending a SMS\r request to the cellular phone connected to the server.

利用奈米級的二氧化鈦〈TiO?〉在紫外光降解幾丁聚醣的研究

本實驗中利用二氧化鈦能在常溫下經紫外線催化,分解空氣中的水分子,產生自由基的特性,攻擊幾丁聚醣中碳與氧鍵結的部分,使chitin 的分子量成功的從近50000 降解至3000以下;並可利用照射時間的不同,降解出分子量不同的chitin。此法不但大大排除利用化學法降解時廢液處理上的問題,而且還能利用照紫外光時間長短的不同來控制分子量的大小;又奈米級二氧化鈦(TiO?)在紫外光在短短四個小時之內就有很好的降解效果,除了節省了反應所需的時間外,降解前後幾丁聚醣的濃度也很高,因此所需的成本也遠低於當今利用酵素降解的方法。In the experiment, we used the properties of TiO? that can be catalyzed by UV rays and breaking the molecules of H?O and produce free radicals, which free radicals can attack the chemical bond between carbon and oxygen in chitin, successfully degrading chitin's molecular weight from 50000 to 3000.We also use different shining times to degrade chitosan into different molecular weight. In this way, we not only readily solve the problem of treating waste liquids produced by chemical degradation, but also control the molecular weight by different UV ray shining time. For another thing, TiO? in the nanometer level has excellent effect on degradation within 4 hours under UV ray shining. It not only cut back the reaction time but also produced high concentration of the chitin after degradation. As a result, the cost is much lower than that of using enzyme to degrade chitin.

關於渦旋〈二〉

在做這實驗之前,我花了很長一段時間思考一個問題:我如何能得到同\r 樣大小(均勻)的水珠陣列?我在家中各個角落放置許多水瓶,看看哪\r 個地方能培養出顆粒相同的水珠? 往往肉眼見到整齊排列的水珠,一經\r 顯微鏡觀察,可就大小不齊整了。\r 第一篇中的實驗,幾乎是「水珠日記」,記載冷凝過程;其中我特地比對\r 「穩定的水蒸氣氣流」與「擾動的水蒸氣氣流」、「水蒸氣氣流與凝結盤\r 間溫度差別」、「凝結盤密度差別」、「凝結因子的重量百分濃度差別」、「水\r 蒸氣氣流之流速差別」,並加以複合比對。希望能找到產生均勻排列的條\r 件–探討水分子的自我組裝機制(Self Mechanism of Water Droplets)。\r 這其中提出『均勻假說』: 當條件合宜時,冷凝下降的細微水珠會產生\r free vortex ring,形成整齊的渦環組合,進而產生均勻排列的細微水珠陣\r 列。\r 實驗是藉由溶液密度小於水的設計,讓水蒸氣冷凝於液面上,並且因密\r 度較大而下沉。設計的要點是:儘量減少細微水珠自冷凝後的堆疊\r (coalescence),以呈現水珠原貌。\r 在第二篇實驗中,將對渦旋比例尺修正。渦旋本身難測大小,在空氣中\r 也不易觀察,但是若由水中觀看,可藉由空氣蕊長短估算。這次更進一\r 步考慮到排水速率、水深、排水口形狀、與極值。\r \r I have tried to ask a famous math professor if he can create a formula\r describing the ordered array of water droplets。〝Then, I should study Physics\r first !〞He said。\r Condensation is the thing we live with , being found everywhere, passing\r without notice。But we never know0 when it does start?\r This experiment presented here is actually the diary of the growth of water\r droplets through condensation。Through convection and vortex ring, it\r discusses the self assembly mechanism of water droplets and peep into the\r uniformity of the size of water droplets。\r Here, vortex ring plays an important role in the self assembly mechanism of\r water droplets which is not triggered in the daily life。\r By coalescence, water droplets grow bigger, but are not round again。We used\r the polymer film as template and designed the solution lighter than water, so\r the minute droplets will sink to the bottom and layer by layer。After seconds\r we may have multilayers of ordered array。\r This is the first step in discovering the uniformity of water droplets, besides, I\r made some correction to the Vortex-Ruler。Vortex-Ruler will be useful in\r researching the flying mechanism of butterfly and dragonfly as to judge\r which one induces more vortices。