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近年來,隨著癌症人口的激增,及一些食物中天然存在或加工過程中衍生出的致突變物質之陸續發現,人們開始注意到含黃樟素, Pyrrolizidine 生物鹼, alkaloid 生物鹼等食物的致癌性和致突變性。而可可鹼( theo bromine, 3 , 7 -dimethylxanthine ),咖啡因( caffeine ),茶葉素( theophylline ),為 alkaloid 生物鹼的三種主要化合物。只要是嗜好可樂或巧克力甜食的人,就免不了和可可鹼有長時間且高頻率的接觸,這不禁令人對可可鹼是否造成遺傳物質的傷害,感到好奇。
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本研究自2002 年4 月至2003 年5 月為止,共14 個月,於台北市金面山區\r 南麓溪谷及生態池,以Twitty 去趾法(toe-clipping method)對拉都希氏赤蛙(Rana\r latouchii)進行族群特性和生殖策略之研究。\r 研究期間內共標記了580 隻(包含畸形蛙65 隻),而雌蛙有190 隻(包含雌畸\r 形蛙19 隻),雄蛙有350 隻(包含雄畸形蛙43 隻),無法分辨公母者有30 隻(無畸\r 形蛙),未判定公母者有10 隻(包含畸形蛙3 隻)。\r 在族群特性的部分,拉都希氏赤蛙之雌、雄個體吻肛長、體重及吻眼比皆\r 有顯著性差異(p
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Johnny the Random Walker-振動平面上的顆粒運動
顆粒在受垂直振動時有擴散、對流的現象,其中對流的情況較難觀察,但表面的擴散可用影像擷取分析系統來測量。本實驗利用喇叭作為顆粒振動的能量來源,將顆粒放入扁平的壓克力圓盒,再用攝影機、ImageJ作為影像分析系統。同時透過顆粒數目與Γ值(振動台最大加速度與重力加速度的比值)兩種變因,分析兩變因對於擴散係數、平均自由徑及平均自由時間、速率分布的影響,探討顆粒在近似於平面上的運動行為。
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高蹺(Himantopus himantopus)度冬族群在八掌溪嘉義市段與台灣沿海各主要棲地數??
台灣地區高蹺?(Himantopus himantopus)的度冬族群出現月份是九月中旬至隔年四月,棲息地主要是在台灣西部沿海之鹽田、魚塭、沙質河口及少數內陸河川,而 1994年成立的台南四草野生動物保護區更是其在台灣的主要繁殖區。 本研究主要從2001年3月~2003年10月進行八掌溪嘉義市段高蹺?族群數量的調查,在 2001.12 月計數到最高數量約 1200 隻,2002.10 月有 1540 隻,連續兩個年度都是全國最高數量,分析環境因子及食物來源皆優於其他各沿海棲地。 在 2003 年 5 月至 9 月調查嘉義沿海高蹺?繁殖配對情形,在 5 月 24 日發現鰲鼓溼地巢數 25 個、幼鳥 14 隻,布袋七區鹽田巢數 9 個,顯示除了台南四草繁殖區外還有其他的繁殖地。 The winter residents of Black- winged Stilts in Taiwan appear in mid-September to next April. Their main habitats are the salt pans, water ponds, sandy river mouths and few inland rivers in western Taiwan. Furthermore, the “Taina Szu-Tao (四草) Wildlife Sanctuary” established in 1994 is their major breeding area. This research is the investigation of the amount of Black- winged Stilt in Pajhang River(八掌溪), Chia-yi city(嘉義市) in 2001, Mar.~ 2003, Oct. The highest amount in 2001, Dec. is about 1200 and in 2002,Oct. is 1540. The amounts of these continuous two years are the highest in Taiwan. To analyze the reasons, the environment and food sources are better than other coastal habitats. In 2003, from May to September, the investigation of mating situation of Black-winged Stilt in Chia-yi coastal areas, twenty five nests and fourteen young birds in Ao-Ku(鰲鼓) wetland; nine nests in Pu-dai (布袋) seven salt pans are found on May 24th. It shows that there are other breeding areas except the breeding areas in Tainan Szu-Tao.
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西爾平斯基船帆與掛毯圖形應用於數位圖形與數位音樂創作
西爾平斯基船帆(Sierpinski Gasket)與西爾平斯基掛毯(Sierpinski Carpet)都屬於碎形(fractals)圖形的一種,可以利用迭代運算系統IFS(Iterated Function Systems)碼來產生,代入迭代運算方程式後,經由多次的運算,可以得到重覆的圖形。本研究中,我將提出一些作法,找出西爾平斯基船帆與掛毯圖形其遞迴關係式,進而討論出其數位圖形之規律性及所涵蓋的內容與性質,著重在推廣西爾平斯基船帆與掛毯圖形的概念,將一段音樂曲取出,把它們看成反覆隨機迭代點,利用程式經由多次的插值運算,計算出各段音符。最後加入基因演算法來解決音符長短的問題,把製造好的音符染色體放置到交配池中,以隨機的方式在交配池中選取其中之一個染色體進行交配的動作,此二音符染色體會交換彼此的基因,產生下一代新的代表音符長短之染色體,應用於數位音樂創作,而衍生的西爾平斯基船帆與掛毯圖形新穎應用與創新的結果,希望能提供數位音樂創作的多樣性,更進而可以找出「好聽的音樂」與數學的直接關聯性。‘Sierpinski Gasket’ and ‘Sierpinski Carpet’ are two graphics that belong to fractals. They can be produced by IFS (Iterated Function Systems). By iterative computation of many times, we can obtain the similar graphics. In my research, there are some methods to generate Sierpinski Gasket, Sierpinski Carpet, and the iterative algorithms. In addition, I would discuss the regularity and the content as well as the properties of those digital patterns. At last, the advanced application of Sierpinski Gasket and Sierpinski Carpet to digital music pieces was presented. The program took a note of several measure of music as the beginning point, and made the IFS calculations for each new note in each measure. But there was no difference in beats if you just make the IFS iteration. So I changed the beats with genetic crossover method. In this research, the expression of the DNA to each beat of note was adopted. The same way, it took a note as a beginning point. And the system obtained the new DNA from the old notes for new ones randomly. That would make a piece of brand new music. What I want to do in this research is improve the multiformity of music and find what the relationship is of ‘good music’ and mathematical algorithms.
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Neuropathy of DRG in STZ-induced DM rats
糖尿病是一種由於體內胰島素分泌不足或作用不良而導致血糖升高的疾病,此慢性病會造成周邊神經病變,影響周邊神經的傳導。本實驗以大白鼠為研究對象,首先將大白鼠分為兩組,一組以腹腔注射streptozotocin (STZ, 60-80 mg/kg),破壞其胰臟之β細胞;令另一組腹腔注射生理食鹽水作為對照組。經過4-6 週,測量其血糖。其中注射STZ 的一組,依照血糖改變分為兩組,一組是高血糖(>126mg/dl),另一組是正常血糖組(126 mg/dl), and the other had normal blood glucose level (
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路邊停車時,總需要三番兩次的調移車身,過程些許費時,因此,嘗試推算一次順利進出車格之軌跡。我們以開出停車格之軌跡做探討,軌跡建立之後再依循所建軌跡供車輛倒車行駛。為了能順利一次路邊停車,我們設定方向盤轉動量最大,讓前輪達到最大轉向角θ(一般車輛是35度),以取得最小迴轉半徑R,利用車輛基本性質,包括:車前懸a、前後輪軸距b、車後懸c及車寬d,推導計算最小迴轉半徑R,所代出之公式經模擬實驗,其誤差率均小於5%,值得引為後續研究之用。於路邊停車軌跡部分,先探討車輛出車格之軌跡,包括:左轉、直行及右轉軌跡,三個軌跡的反向連續軌跡,即為路邊停車時倒車的應行進軌跡。於倒車入庫軌跡部份,則包含直行及右轉軌跡兩部份。最後,對於誤差修正之探討,我們提出所謂前輪轉動受「軸承」控制之計算觀念,將車輪轉動中心砌合實際狀況轉移,於給定承軸及輪胎外側圓心之距時,將有更精密之數據展現。
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加法鏈上的Scholz-Brauer猜測之研究
給定一個自然數n,如何最有效率的計算Xn?此處Xn表X自乘n次,X可以是任一具有乘法的代數體系中元素;所謂最有效率是指使用最少次的乘法。由此引發了“加法鏈”的概念及許多有趣的數學問題。Knuth[1]的話恰說明了本研究的動機:\r Not only because it is interesing in its own right, but because it is an excellent example of the theoretical questions that arise in the study of "optimum methods of computation."
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Artificial Photosynthesis -Formic Acid Generated from Carbon Dioxide by Using Photocatalyst-
Reduction of carbon dioxide is desired as an environmental problem of global warming. The study of generation of formic acid from carbon dioxide was performed under irradiation of ultra violet to photocatalyst. Ta2O5 could reduce carbon dioxide, but the band gap of Ta2O5 was 4.0 voltage. In this research, it was found that tantalum oxide / tantalum plate responds to visible radiation. Therefore, the reason of visible light response was examined. It was studied to make efficient tantalum oxide / tantalum plate.
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座標平面上任三點與X 軸之最短距離和
我們的題目是”座標平面上任意三點與x軸的最短距離和”。我們一開始直接由尺規作圖著手,把距離和最小時的那點設為p,但始終無法找到一個方法精確畫到p點。後來變轉入公式的研究,我們設第一象限中A B 和C三點,固定A B C的y座標為d,並討論不同d時的情況,求出B點的範圍。另外我們也從橢圓方面著手,但此部份目前還待努力。;A B and C are three points in the plane, and L is a line in the same plane. Our target is to find a point P in L make the sum of PA+PB+PC minimum. At first we undertake by drawing pictures but we can’t find the solution we want in any case. We make L to be X-axis make A B C’s Y-coordinate to be d, and then we discuss various situations of d, and figure out the range of B. We also analyze the situation in oval, but still have no conclusion.
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New Screening Method for Early Pediatric Cancer Detection Through Automated Handwriting Analysis
Pediatric cancer has an incidence rate of more than 175,000 per year with a mortality rate of approximately 96,000 per year. One major cause of this problem is late diagnosis. A novel promising way of pediatric cancer screening is handwriting analysis. This method surpasses other methods by detecting pediatric cancer in a very early stage. However, studies are still limited to manual analysis which needs an expert and a long period of time. The aim of this project is to design a computer program to extract handwriting features and build a classification model to classify the user as patient or as control. Dataset was collected from schools and hospitals where all participants could read and write in English. After data cleansing, number of samples was 440 samples. MATLAB (Matrix Laboratory) program was used for extracting geometric features in handwriting. Program was validated using a subset of 50 samples of the dataset. WEKA Package was used to test and build the classifier. Experiments were done using classifiers: Logistic, Multilayer Perceptron, J48, LibSVM, AdaBoostM1 and Naïve Bayes. Best subset of attributes was evaluated and used for each classifier and all calculations were done as the average of cross validation operations of several folds assignments. Best performance was achieved by Logistic classifier with average accuracy of 80.15%, standard deviation of 0.43% and Matthews's correlation coefficient of 0.59. Finally, this project presents a new fast, free, ready, easy and psychologically comfortable method for pediatric cancer detection while keeping suitable accuracy for mass screening.
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Research the efficiency of the fog-catching nets
Islands far from lands use the underground or surface water as the water for living. The population of the islands is growing fast and the amount of water usage is increasing year after year. However, the amount of water usage is limited, so that people who live in islands have trouble using water. To compensate this problem, underground water is drawn from deeper underground sites. If this matter occurs continuously, sea-level may rise and then we cannot use underground water. Seawater desalination is a way to solve the water shortage, but it requires a lot of energy. It is difficult for island far away from lands to supply a lot of energy. It is considered the eco-friendly way to minimize the use of energy on the island. In order to solve the problem of water shortage on the island, it is considered fog that on the island occur frequently. It is an attempt to create water from fog, but it is a lack of research of efficiency of fog-catching nets to create water from fog. In this research, I have studied the efficiency of the fog-catching nets, a way to increase the efficiency, the amount of water that is created on the island, usage of discarded fishing net for fog-catching nets. Through this research, I found a kind of fog which can be changed into water and the difference in efficiency due to the difference in the size of the mesh size of the fog-catching nets, wind direction, wind speed, water absorption capacity of thread of fog-catching nets, installation direction of fog-catching nets, a way of installation of fog-catching nets. Also I found fog-catching nets of discarded fishing nets on the island and the possibility of usage for everyday life that the amount of water are created for a day or a month during dry season on the island.
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