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中文摘要:\r 本研究旨在探討,在TCP/IP 協定之下,最大網路傳輸效率之MTU\r (Maximum Transmission Unit,最大傳輸單位)值。根據IEEE 所公\r 佈Ethernet 之標準,經實地模擬實驗,本研究之結論如下:(1)在\r 單純兩台電腦直接串接時,由於幾乎無任何干擾與封包的碰撞,可設\r 定之MTU 最大值以1500bytes 為最佳;(2)但在模擬真實的大型廣域\r 網路時,由於碰撞增加及雜訊增多,經模擬實驗顯示,MTU 值為\r 1500bytes 時無法在資料傳送、接收及重組時取得平衡,最佳之MTU\r 值落於500 到600bytes 之間,進一步研究顯示MTU 值設在500 到\r 600bytes 時可提升傳輸效率約50%。同時,本研究亦討論將此機制應\r 用於未來新網路標準之可行性及其必要性。Abstract:\r The main purpose of this research is to explore the best network\r transmission efficiency's Maximum Transmission Unit under TCP/IP\r protocol. According to the Ethernet's standard of IEEE and simulated\r experiments, the outcome of this research are :( 1) When connecting two\r computers serially, there is almost no interference and impact of packets,\r the best MTU that we can set up is 1500bytes ;( 2)When simulating the\r truly wide area network, interference and impact are rising. The result of\r this simulates experiment shows that when MTU is at 1500bytes, it's\r unable to keep balance when sending, receiving and re-composing. The\r best new MTU is between 500bytes and 600bytes. And when MTU is\r between 500bytes and 600bytes, the network transmission efficiency can\r be promoted about 50% higher. At the same time, the research is also\r discussing the feasibility and necessity of applying it to the standard of\r the future network.
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由6面Sicherman骰子來分析n面的Sicherman骰子
Sicherman 已經找出與兩顆六面的正常骰子有相同機率分布的Sicherman 骰子,並進一步獲得與三顆六面的正常骰子有相同機率分布的骰子必為一對Sicherman 骰子與一顆六面的正常骰子之結果,我們試圖由已知的Sicherman 六面骰子的處理方法出發,透過對割圓多項式的分析來累積足夠的相關資料,以處理由兩顆四面骰子至兩顆三十面骰子,處理由三顆四面骰子至三顆三十面骰子的各種Sicherman 骰子的答案,來探索兩顆與三顆的n 面Sicherman骰子存在的充要條件與求法,並進一步將所得之結果分類,得到 ”有相同標準分解式的類型的數n,會具有相同組數的Sicherman 骰子”之猜測結果與特殊情形下的證明。 Sicherman has found out the Sicherman dice which have the same probability distribution as the normal two six-sides dice. Furthermore , he also found out a pair of Sicherman dice and a normal six-sides dice has the same result as 3 normal six-sides dice . We try to begin with the given algorithm of six-sides Sicherman dice , through the analysis of Cyclotomic Polynomials to accumulate sufficient related information then to come up with the solution from discussion of 2 four-sides dice to 2 thirty-sides dice , from 3 four-sides dice to 3 thirty-sides dice to explore the existence of necessary and sufficient condition and solution of 2 n-sides Sicherman dice and 3- sides Sicherman dice , and even to classify the results to come to a conclusion of the guessing results and proofs under special cases about “the numbers n which have the same Canonical Prime Factorization will have the same numbers of n-sides Sicherman dice.”
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My Science Fair project last year tested a local native plant for it’s toxic effects on insects (fruit flies), bacteria, fungi, and viruses. The root of the plant Lomatium dissectum, had been used by the Salish People to control lice and other insect pests in horses and cattle. The root was also used to kill fish, which could then be harvested by women and children. The fish killed in this way were not harmful to eat as long as they were consumed soon afterward. I have found also that fishing with the aid of plant toxins was formerly very common in tropical Africa. \r Lomatium dissectum, grows in dry rocky slopes in conjunction with Sagebrush.\r Many desert plants produce toxic substances that inhibit the growth of competing plants\r nearby. This adaptation is called Allelopathy. In a natural ecosystem, Lomatium does not\r kill fish because it does not grow beside creeks. But this raises the question of whether\r allelopathic plants growing outside their natural ecosystem are having a toxic effect on\r animal life. There are introduced invasive weeds that are allelopathic, such as\r Knapweed,growing near streams. And there are crop plants that are allelopathic – Rye and\r Alfalfa. Do these “natural herbicides” also kill fish? Walnut trees are allelopathic and\r compounds from Walnut kill fish.\r If this effect does go beyond toxicity to other plants, it would be an important\r consideration to environmental guidelines for private land bordering on streams and\r rivers. The B.C. Ministry of Environment notes the importance of shade cover for\r spawning streams. It does not recognize the harmful effects of introduced plants. Yet,\r when we were purchasing supplies for our Koi Pond the pet supply company offered a list\r of “Some of the Worst Plants to Have Around Koi”. We do not know if the introduced\r allelopathic plants are poisoning fish or reducing fish stock by poisoning the food that fish\r need.\r Science Fair rules do not allow any research that is expected to have any negative\r impact on vertebrate animals. Because of this, I have decided to test the effect of\r allelopathic plants on fruit flies (Drosophila). Fruit flies are similar to fish since, during\r larva and pupa forms, they live in direct contact with their culture media. I will also be\r testing the effect of allelopathic plants on Planaria (Turbellaria), an aquatic invertebrate.
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Drought and inundation are two unusual natural disasters in Taiwan. The two natural disasters\r have some relation of abnormal rainfall become more and more in Taiwan. So it let me think about\r can climate vicissitudes make the chance of abnormal rainfall become more?\r The study have researched the chance of abnormal rainfall by "rainfall duration" and "total\r rainfall". It collect the day by day total rainfall from 1960 to July 2002, collect locals are Taipei,\r Taichung, Kaohsiung and Hualien. Than enter the data into the computer, let computer calculation\r total rainfall, rainfall days, heavy rain days, pouring rain days and torrential rain days. Then\r analysis the tendency of long-term change.\r According to the analysis, the chance of abnormal rainfall happened become more in Taipei,\r Taichung, Kaohsiung and Hualien. The ratio of Hualien and Kaohsiung is the most obviously. It's\r also find that there temperature and total evaporate became higher, the total sunshine duration\r became lower. Then El Nino have some influence in abnormal rainfal. In El Nino year, total rainfall\r will become lower. When La Nina year, the total rainfall will become more in Taipei and Hualien.\r Then the long influence is clearly in Taipei.\r 乾旱與水災是台灣地區相當常見的二項天災,這二項災害的發生都與異常降水有直接的\r 關係。近年來台灣地區因異常降水造成的天然災害,似乎有逐年增加的趨勢。因此讓人聯想\r 到氣候變遷是否會導致異常降水頻率增加。\r 本研究主要由「降雨時數」與「降雨量」二方面探討異常降水發生頻率。先收集台北、\r 台中、高雄、花蓮四地自1960 年至2002 年七月三十一日之逐日雨量資料,將資料輸入電腦\r 後,統計各站歷年降雨量、降雨日數、大雨、豪雨、暴雨日數,並分析長期變化趨勢。\r 分析結果,台北、台中、高雄、花蓮四地異常降水發生機率,有增加的情形;其中以花\r 蓮及高雄變化的比例最高。再與其他各地氣象要素比較可發現,可能與氣溫及蒸發量數上升,\r 以及日照時數縮短有關。另外聖嬰現象也可能對異常降水有長期性的影響。一般而言聖嬰年\r 雨量減少,反聖嬰年台北、花蓮地區雨量反而會增加。而長期性的影響,以台北地區最顯著。
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台灣水生食蟲植物~ 絲葉狸藻捕蟲行為及消化功能的進階探索
The “Insectivorous Plants”﹐ the first historical publication by Charles Darwin﹐contained the detailed observations and meticulous descriptions of various carnivorous plants and had become the most important reference for the study of carnivorous plants﹒ But the prey mechanism and digestive function of the bladder traps of the Utricularia were not well described﹒ The present study has a great success in these fields which include the volume change of bladder traps before and after firing﹐the spontaneous pressure relief of the bladder traps even without being triggered by prey, and the quadriceps visible absorption process﹒ The last two findings are not yet publicated. This laboratory experiment is carried out with Utricularia Gibba﹐a native species of Utricularia in Taiwan﹒ Through static and dynamic observation﹐we find that bladder traps suck in water by 12-25% of body volume change, and the bladder traps release internal pressure spontaneously under long period of waiting, despite not being triggered﹒ We can also easily demonstrate the absorption process of quadriceps by manually triggering the bladder traps to suck food color solutions. All the events above can be clearly seen under microscopy﹒達爾文是最先對食蟲植物作深入且完整研究的科學家,至今他的著作仍是研究食蟲植物的重要資料,但在其內容中對狸藻捕蟲囊捕蟲行為及消化功能的研究觀察並不完整。本實驗使用簡單的方法,在這方面有突破性的進展,包括捕蟲囊捕食前後的體積變化,自發性舒張及囊內腺毛對於食用色素的消化吸收,後兩項發現及實驗均未曾出現在文獻資料中。 本實驗以台灣本土水生食蟲植物絲葉狸藻(Utricularia gibba)為研究對象,由靜態及動態觀察,顯示捕蟲囊捕食前後體積變化為12~25%,且即使在沒有捕到水中生物的情況下,也會有自發性舒張以解除囊內壓力的現象。捕蟲囊內四爪腺毛消化吸收功能的整個過程,可藉由食用色素加以呈現,並清楚的在顯微鏡下觀察到這些現象。
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本研究以碳化矽(SiC)奈米粉末加入去離子水中,插入銅電極加以電壓進行其表面帶電性的研究。研究中發現SiC奈米粉末的表面帶有負電荷,且加以電壓後,SiC奈米粉末會沉澱下來。利用場發射掃描式電子顯微鏡(SEM)及X-光繞射儀(X-RD)檢測其性質,發現加以電壓使奈米粉末失去電荷而聚集沉澱。同時經由製作不同酸鹼度SiC奈米粉末溶液的陽極極化曲線發現pH值越大,SiC奈米粉末表面電位越高,開放電路電位越小。本研究實驗過程中發現pH值2之SiC奈米粉末溶液加過電壓後,正極生成一透明薄膜狀物質,極有可能是導電鍍膜,應用價值極高。本研究已先進行微硬度試驗與金相實驗,將由長庚大學機械系研究所進行更深入檢測與研究。The electrochemical behavior of the SiC-nanopowder in deionized water was studied. The electrochemical cell was composed of two pure copper electrodes, across which different voltages were applied. The morphology of the nanopowders or even with reacted products was examined using field emission electron microscope(FESEM) and the corresponding phases were identified with X-ray diffraction method(XRD). The experimental results show that tha nano-powders precipitated at the surface of the anodic copper electrode and in the same time the nanopowders in the solution aggregated when 20 volts were applied across two electrodes. That is, net negative charge could be induced around the nanopowder. Deposition rate of the aggregated powders in the various pH-value solutions was evaluated and the aggregated powders were examined with FESEM. The higher Zeta potential of the SiC-nanopowder was examined as the nanopowders immersed in the higher pH value solution. The nanopowders aggregated themselves as the pH value under 2. The anodic polarization behavior of the copper electrode in SiC- nanopowder solution was measured and the results were compared with the aforementioned tests.
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極速骨牌-骨牌終端速度及鏈鎖反應機制之探討
本研究主要在探討骨牌脈波在傳遞時的速度變化,並比較在不同的骨牌和不同的排列方式下骨牌的終端速度有何種差異;同時也研究骨牌在鏈鎖反應下能量的放大現象。觀察後發現單列骨牌脈波在傳遞一段距離後,由於空氣阻力的影響,脈波將會達到一終端速度,此終端速度與骨牌高度成反比,而與骨牌質量平方成正比。骨牌的脈波傳遞在鏈鎖反應下仍有一終端速度,但大於單列之骨牌脈波速,且鏈鎖反應具有放大推力之功能。由我們的研究可預測一列物體傾倒時所花費時間和所能達到之終端速度,而鏈鎖反應可比擬為一雷射模型能量集中和釋放的機制,相信可利用骨牌儲存能量的機制應用於需迅速釋能的機械中 This research is mainly discussing the changing of velocity of a domino pulse, and comparing the terminal velocity of various kinds of dominos and arresting modules. Also we focus on the energy-enlarging fact of chain-reaction of domino series. We found that after running a distance, the pulse of a single-series domino will finally reach a terminal velocity by the friction force of air. The terminal velocity will inversely proportion to the height of a single domino, and will proportion to the square of mass of a single domino. During a chain-reaction, the pulse still has a terminal velocity, but it is higher than the terminal velocity of a single series domino .The chain-reaction has an ability to enlarge the original force, too. By the research, we are able to predict the time interval and the terminal velocity while a series of objects are falling. On the other hand, the chain reaction is similar with mechanism of energy concentration and emission of LASER. We also believe that this mechanism is able to explain and apply to those machines which need to release energy rapidly.
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High Speed Size-exclusion Chromatography (SEC) Using Spherical Meso-structured Cellular Foam (MCF)
Size-exclusion chromatography (SEC) is often used to determine the molecular weights of and separate polymers and proteins. The porous packing of the SEC column effects the separation of molecules, with larger molecules eluting earlier. Interest in high-speed SEC for larger molecules has been building, especially for combinatorial polymerization reactions and online SEC-MS applications. Mechanical stability of the packing, which siliceous materials have more of than polymeric ones, therefore needs to be improved. Several silicas have been explored but limited pore sizes and pore volumes have restricted their usage to separating small molecules. Siliceous MCF templated using oil-in-water microemulsions has good potential for SEC packing because it has ultralarge pore size (20-50 nm), high porosity and sturdy skeleton. However conventional MCF consists of highly irregular particles and hence cannot be used as packing.
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表面粗糙結構對疏水性影響之應用與研究
本研究從大自然中之「蓮花效應」引發學習興趣與研究動機,在蒐集相關資訊與文獻後,發現疏水功能不只是防水,還關係著日常生活品質之許多材料特性,包括防水、撥水、防潮、防銹、防蝕、抗菌防污、自清潔…等。而影響固體表面疏水性之兩大特性,包括物理之表面粗糙度與化學之超低表面能,本研究針對物理之表面粗糙度與疏水性之關係做探討,以相同之化學特性來比較不同號數之工業用砂紙之疏水行為,並就廣泛被引用之兩種模擬表面粗糙度與疏水性關係之模式:Wenzel and Cassie model,比較現有文獻對兩種模式之特性,選擇Cassie model 來進一步實驗驗證,以量測之平均接觸角 Θ 推算Cassie model 之表面粗糙係數Φ 值,並簡化不同砂紙顆粒模型為相同粒徑之球狀,以簡化之方程式來求得水珠與砂紙顆粒之實際接觸面積與球心夾角 θ,以提供高中學校能在經費與設備之限制下,仍能有效應用與印證Cassie model,獲得砂紙顆粒直徑與球心夾角 θ 自然對數值之關係。並就疏水性之生活應用,建立接觸角與 Φ 之關係曲線,驗證實驗之方程式,與延續過去之科展成果,以實驗成果提出可行性應用之建議。The interest and motivation of the present work was introduced from “lotus effect” in nature. After we collected related literature and information, we found that the function of the so-called “superhydrophobicity” behaves not only water repellency, but also a variety of real-life applications, including anti-fog, anti-corrosion, anti-bacteria, anti-fouling, self-cleaning, and so on. Pervious studies have pointed out that two criteria affecting the performance of hydrophobic surfaces are physical (roughness) and chemistry (surface tension) properties. This study focused on influence of physically surface roughness on hydrohyphobicity. Based on an identical surface chemistry, we employed different types of industrial sandpapers to mimic the lotus leaf, and investigated the relationship between roughness and hydrophobicity by using two famous models: Wenzel and Cassie models. Comparing with their basic assumptions to our study, we applied Cassie model to confirm our experimental results, in where one Cassie parameter (?) was proposed to simplify the Cassie equation. This superhydrophobic behavior can be well predicted by the Cassie model. This study continues previous achievement and offers some practical utilization according to our\r experimental results.
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The main reason for the creation of the project was looking for the uncondutuinal support for the entire handicap people that reside in the whole world. \r In all the communities there are barriers that oppse the total development of these people, and what currently exists can not help achieve a full lige for example: it's hard to have a basic education, a productive employment, or in their case to have a simple normal life.\r at the present time there is a serious problem of inequality, this is presented beacuse there has not been a mechanism that has been albe to please 100% of its real demand. That's way what we seek with this prototype, to be able to help them to have and live a better quality of life, it has the function of warning them when an object is near or before them emitting a brief sound that dose not cease until the way is completely free of obstacles, it is also sought to prevent accidents lkie falls, trips, among other, and also to help create more accsess possibilities to help any people that suffer any kind of handicap.\r This is a prototype that is able to help blind people, by heping them become able to move from one place to an other more faster and more securely, these is trying to make them more sure and reliable on them self, also the project is very economical and it was created due to the high quantity of blind men and women that exist in the whole world
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Palatability Tests on Rana Chalconota Tadpoles
The skin of amphibians can secrete poisons from glands which reduces Palatability or sometimes result in rejection by predators. My research serves to confim the hypothesis that the pair of glands located on the ventral side of Rana Chalconota Tadpoles acts as an anti-presatory structure. Their palatability was measured by the consumption of them at developmental stages intermediate and post-metamorphic by Channa gachua and Giant Dragonfly Nymph. A known-palatable tadpole, Rana malesiana, was used as a control.
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This experiment mainly aims at three kinds of solution - Dextrose, Saccharose, and Fructose. By changing its temperature, density, length of tube, as well as different wave length factor of polarized light, we observe the influence of the direction of polarization by those factors. The experimental result showed as follow. The Dextrose and the Saccharose can cause the polarized light with the rotary direction of clockwise, so both are ‘dextrorotatory’. The Fructose can cause the polarized light with the direction of counterclockwise, so it is the ‘laevorotatory’. For the Dextrose, when the\r temperature is lower than 20℃, the direction of polarization has changed observably, but doesn’t have any rule. When the temperature is higher than 20℃, the direction of polarization increase slowly. For those three kinds of solution, when\r density increased, the polarization increased observably. When the polarized light passed through the solution with longer path, the direction of polarization has more change. When the wave length of the polarized light changed, the direction of polarization has been changed observably. When the wave length of the polarized light is shorter, the direction of polarization change increased.本實驗主要針對葡萄糖、蔗糖、及果糖等三種旋光性溶液,改變其溫度、濃度、容器管長、以及不同波長的偏振光等因子,觀察這些因素對偏振方向所造成的影響。實驗結果顯示:葡萄糖與蔗糖會使得偏振光的偏振方向以順時針旋轉,屬右旋性之光學異構物;果糖會使得偏振光的偏振方向以逆時針旋轉,屬左旋性之光學異構物。若溶液為葡萄糖,當溫度低於20℃時,偏振光的偏振方向會有明顯的改變,但無規則可尋;當溫度大於20℃時,偏振方向旋轉角位移則以非常緩慢的方式增加。當此三種溶液之濃度增加時,偏振光的偏振方向有明顯遞增的現象。此外,當容器長度越長(即偏振光在介質中的行程越長)時,偏振方向的改變亦越明顯。當偏振光的波長改變時,偏振光的偏振方向有明顯的變化,且當偏振光的波長越短,偏振方向的改變越大,似乎與波長呈反比,但此結果與理論值(即旋光度與波長平方成反比)仍有一些差距。
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