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流量計在實驗室與工業領域裡是重要的儀器,如今已經有數十種依不同物理原理而發展出來的型式,可以配合多變的環境需求與測量條件而使用。然而,各種流量計所適用的範圍備受侷限。本研究主要目的在發展一種熱線式的渦流流量計,供給氣體之流量量測之用。透過自行製作儀器與設備:熱線測速儀(包括探針、探棒及電子處理器)和渦旋產生器(管道中含一三角形截面之鈍體,當流體通過時,在後方尾流產生週期性渦旋逸放)。由於熱線測速儀擁有偵測流體運動時高頻動態變化的能力(約為20000 Hz 以內),因此結合熱線測速儀與渦旋產生器,經適當的設計與調校,可以測得在不同流體流速時渦旋產生器的三角截面鈍體後方渦旋逸放的頻率。由於渦旋產生器的截面面積為固定值,因此可以從而計算出流量與渦旋逸放頻率的關係。經由嚴格的校準與驗證步驟,本研究的結果顯示自製的熱線測速儀擁有極佳的渦旋頻率偵測能力,所量測到的校準曲線顯示渦旋產生器的三角形截面柱所產生的渦旋逸放頻率與流量成線性關係。為了降低誤差,建議在0 ~ 40 CMM 之量測範圍內分成三條方程式來代表不同範圍內的校準曲線,最大誤差僅在5%以下。若需使用在不同的流量範圍時,僅需改變渦流產生器和幾何尺寸,以使渦旋逸放頻率適合於熱線測速儀的動態響應範圍即可。倘若商品化之後,可以實際應用於風扇流量量測、引擎進氣埠流量的測量等等應用。熱線測速儀本身也可作為風速計,適用於各種場合之風速量測。Flow meter is a instrument that is vital to the laboratory as well as the industrial related field. Based on different physical principles, tens of models that work in harmony with the diverse environmental demands and measurement conditions are developed to date. However, the application of varied flow meters is still under severe restriction. The purpose of this study is to develop a hot-wire type of vortex shedding flow meter for the use of flow rate measurement. Through the home-made apparatus and device, the hot-wire anemometer (includes probe, stem and electronic processor) and the vortex generator. (duct that contains triangle’s section of the bluff body. When fluid passes through, the wake behind produces periodical vortex shedding.) The ability of hot-wire anemometer when it detects the fluid moving changes of high-frequent movement is within 2000Hz, after appropriate design and adjustment, the combination of hot-wire anemometer and vortex generator may investigate the frequency of different flow rate that generated from the vortex shedding behind the bluff body of triangle section. The section area of vortex generator is constant value, thus it can calculate the relationship of flow rate and the frequency of vortex shedding. By means of strict calibration and test procedure, the results reveal that home-made hot-wire anemometer has excellent ability to detect the frequency of vortex shedding. The calibration curve indicates a linear relationship between the frequency of vortex shedding and flow rate. In order to reduce inaccuracy, it is suggested to classify three formulas to represent the flow rate that ranges from 0 ~ 40 CMM. The greatest inaccuracy is under 5%. When applied to different flow rate range, it only has to change the size of vortex generator only if the response frequency of hot-wire anemometer suit for the range of frequency of vortex generator. After commercialization, it can be applied to measure the flow rate of fans, flow rate of intake valve of engine, etc. Hot-wire anemometer also served as anemometer, which can be applied to wind velocity measurement in any situation.
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令a,b,c,表 △ABC三邊的長,△表△ABC 之面積,若 a , b , c . △ 皆為整數”則 △ ABC 稱為整數三角形,此 a , b , c 三數稱為Heronic triples · 當( a , b , c )=l 時,稱為 Primitive Heronic triPles ,如 3 , 4 , 5 ( △ = 6 ) , 5 , 5 , 6 ( △ = 12 )皆是,大家所熟知的畢氏三數賞為 Heronic trlPles 的特例。由畢氏三數所形成之畢氏三角形即是有一角為直角的整數三角形(參考資料 l ,Vol.8 No.3 ( 1975 / 76 ) )。般近 Mathenatlcal spectrum 發表了幾篇文章.皆是討論 Heronian triangles 最近發表的 John strange, ( Volumn 10,No.l ( 1977 / 78 ))曾提出一個待解決的問題 :「Given a natural numbern determine every Heroulan triangle whose area is n」筆者利用 I . B . M 計算機計算出 729 組整數三角形的數據(參考附表一) · 發覺每一個整數三角形的面積皆為 6 的倍數。
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本研究首先確認培地茅根系具有碎形之基本特性,再進一步以方格覆蓋法計算之碎形維度來分析培地茅根系在不同時間及環境因素下的生長。主要探討碎形維度與抓地力之關係,並設計以實際根系模型來加以模擬,並發展出一可描述抓地力與碎形維度及深度關係的方程式。我們的結論為:(1) 經由方格覆蓋法之計算,培地茅此種植物,不管是整個根系或單枝根,均具有碎形基本特性,適合進一步實驗研究。(2) 碎形維度會隨著培地茅生長時間增長而增加,並且在自然光照及30℃左右會有較大值,而種植於土壤中根系發展較廣,其碎形維度比種植於沙耕中來的高。(3) 實驗結果顯示,抓地力受碎形維度及根系深度兩因素影響,而培地茅根系對土壤有較強的抓地力,推測是因為兩者根系皆又深又長,土中培地茅根碎形維度較大,接觸面積較廣,而又進一步以矽膠模型做實驗驗證。(4) 矽膠模型之目的在於減少難控制之自然變因,實驗之前,測量了根系模型與洋菜凍之基本性質,實驗結果顯示抓地力與碎形維度及根系深度皆呈正向關係,可用數學方程式加以描述。This project is mainly a research into the fractal dimension of the vetiver root system. First, we confirm the vetiver root system has the basic fractal structure by checking its self-similarity, then using box-counting method to calculate fractal dimension. We begin with a fundamental investigation into the relation between different time and environmental factors and fractal dimension. Then we move to our main point: the relation between fractal dimension and its pull-out resistance. In the next step, we make a fundamental silicon model, simulating the vetiver root system, to continue our experiments. In the end, we develop a formula that can describe the relation between its pull-out resistance, roots depth and fractal dimension. Here are our conclusions: (1) After using box-counting method to calculate fractal dimension, we discover that not only the whole vetiver root system but also a single vetiver root has the basic fractal structure. (2) Fractal dimension increases when time goes on. Also the value of fractal dimension is larger in natural sunlight and the temperature at about 30℃.The vetiver root system grows more widely in soil than those in sand. That’s why it has larger fractal dimension. (3) Data shows that its pull-out resistance is influenced by both fractal dimension and the depth of the roots. The vetiver roots, in the meantime, show greater pull-out resistance than some other plants. Thus we draw the assumption that the vetiver root system grows deep and wide, and in natural soil its fractural dimension is greater and reaches greater area. Therefore, a silicon model is constructed to further confirm the findings of the experiment.(4) The design of the silicon model is to reduce the uncontrollable variables in nature. Before starting the experiment, we measured some basic characteristics of the silicon model, including density and angle of repose. Furthermore, the experiment demonstrates that pull-out resistance and fractural dimension have a commensurate mutual relation: the stronger the pull-out resistance, the wider the fractural dimension and the deeper the root system. Thus we derive a math formula to describe this relation.
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少年「π」的奇幻旅程--不對稱切割之內外夾擊
自古以來,幾何法求圓周率,由於太執著於把圓或角度做等分,都會面臨開根號與無理數的問題。本文第一階段,改以不對稱切割來避開無理數。先定義有理數r和角度θ的映射函數T,發展出另類分割圓周的簡易方法,讓圓的外切與內接多邊形邊長都呈現為≤1之最簡正有理數,並計算初步之 值。第二階段,則藉由外切與內接多邊形對圓面積的逼近探討,來導出一個大幅提高 值精確度的加權校正公式。第三階段,更是結合前兩階段之理論,進一步推演出計算簡易的 值逼近定理:π=4xΣr(k,t)/3(2+1/1+r2(k,t))與更嚴謹的π值夾擊定理:4xΣ(3r(k,n)/3+r2(k,n))
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Automated Traffic Light
This Project is inspired by the situation incurred by pedestrians, which for the most part are students who need a crossway in order to obtain public transportation or to get to the school; the difficulties that are faced by the personnel to exit the parking lot as well as the students who have a vehicle and to help those parents who drop and pick up their children at the school. At the same time, we would like to reduce the amount of contaminated gas emissions that are emanated into our environment. As consequence of the emission of toxic substances, the air contamination can cause side effects such as the burning of eyes or ears, throat irritation and itching and or respiratory problems. Under determined circumstances, some chemical substances that are found in the contaminated air can produce cancer, congenital malformation, brain damage and disorders to the nervous system, as well as, pulmonary damage and harm to the respiratory tract. For the present investigation it has been suggested as a primary goal: The development of a device, in this case a traffic light, which has the objective to reduce the previously mentioned traffic/security problems that arise upon entering and exiting the institution. The secondary goal is to have a friendly ecological impact within our community. This device was built and tested during a month to obtain figures and demonstrate benefits reported. The device should be low maintenance, it should have a long lifetime and, be simple enough to be operated by those who use it. Among the benefits found, the safety of the students, the prevention of accidents such as: car crashes and run overs, etc. Our studies indicate that per week it is consumed an average of 2,020.16 liters of gasoline, in schedules of 13 hours (from 7:00 AM to 8:00 PM) to lessen this figure would have a good ecological impact since all the hydrocarbon emission are harmful to health.
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可表為兩個平方數和的一種特定型式的數及其性質推廣研究~「Concatenating Squa
給定下面範例:\r 058823529411764705882 +235294117647058823532\r =0588235294117647058823529411764705882353,\r 其等式結果與質數17 的倒數結果(1/17)有某種關聯(卻沒有一個決定性的證據),意即\r 1/17=0.0588235294117647=\r 0.058823529411764705882352941176470588235294117647...... ( Len(17) =16 )\r \r 曾經在下列網站上發現過幾組數字(挑戰試題),引起我們極大的興趣。\r http://www.domino.research.ibm.com/Comm/wwwr_pondernsf/challenges/March2000.html\r http://www.math.smsu.edu/~les/POW08_96.html\r \r \r The two examples that I have are 0588 2+23532=05882353 and 058823529411764705882+23529411764705882353 2=0588235294117647058823529411764705882353 These were found by the Canadian professor Alf van der Poorten, and he gave a talk on these identities in December at the west coast number theory conference. He was unspecific as to exactly where these identities were coming from, but they are connected with reciprocals of primes:1/17 = 0.0588235294117647= 0.058823529411764705882352941176470588235294117647 ΛΛ ( Len(17) = 16 ) Though not mentioning how to obtain these equations, Prof. Poorten demonstrated the relationship between the above examples and the reciprocal of the prime numbers 17 (1/17 ) without a definitive proof.
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Lose Trail Pheromone? Application of adult transport to optimal feeding strategy of the Asian needle ant, Pachycondyla chinensis.
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如果n-1 個正四面體在n 個面的多面體棋盤中翻轉(如:正八面體、正二十面體、五邊雙菱錐及三角錐台棋盤),則正四面體相互之間會受到很多限制。本研究為探討n-1 個正四面體在n 個面的多面體棋盤中,利用其翻轉的特性,翻轉至相鄰空格,進而完成:1. 每個正四面體的底面及側面均能「同色共面」。2. 在滿足以上的兩個條件下做「數字排序」。3. 探討每個遊戲在各階段是否有解的情形。最後,將遊戲推廣至正八面體在多面體棋盤中的翻轉。If n-1 pyramids can turn in the chessboard of n planes pyramids (ex: 8 planes pyramid, 20 planes pyramid, 5 sides bi rhombus pyramid and triangular pyramid chessboard) there are lost of restrictions between these pyramids. This research is discussing about the n-1 pyramids in the chessboard of n planes multi pyramid, which have the peculiarity of turn that can turn to nearby space. We found that: 1. Each pyramid’s button plane and aide plane can be “same plane same color”. 2. Matching about 2 conditions then can do “order by numbers”. 3. Search for answers of each levels in each game. Finally, the game will be propagated to eight planes pyramid can turn on the chessboard of multi pyramid.
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At the website “MathLinks EveryOne,” we found a problem “Snakes on a chessboard,” which was raised by Prof. Richard Stanley. The following is the problem. A snake on the m n chessboard is a nonempty subset S of the squares of the board with the following property: Start at one of the squares and continue walking one step up or to the right, stopping at any time. The squares visited are the squares of the snake. Prove that the total number of ways to cover an m × n chessboard with disjoint snakes is a product of Fibonacci numbers. We call the total number of ways to cover a chessboard with disjoint snakes “the snake-covering number.” This problem hasn’t been solved since it was posted on September 18, 2004, so it aroused our interest to study it. First, we used the way in which we added each block to the chessboard, and therefore we discovered some regulations about the snake-covering number of the1 × n , 2 × n and 3 × n chessboard. Through “recursive relation” and “mathematical induction”, we proved the general term of the snake-covering number of the1 × n , 2 × n and 3 × n chessboard. In the following study, we found a key method in which we added a group of blocks to the chessboard. Finally, we proved the general term of the snake-covering number of the m × n chessboard. Also, we discovered the way to figure out the snake-covering number of the nonrectangular chessboard.在網站“ MathLinks EveryOne ”中,我們找到了一個有趣的問題“棋然上的蛇” ( Snakes on a chessboard ) ,這個問題是由教授 Richard Stanley 所提出。問題如下:在m x n棋盤形格子上,蛇由任意一格出發,但蛇的走法只能往右 → ,往上↑,或停住 ‧ 若此蛇已停住,將由另一條蛇來走,且不同蛇走過的格子不可重疊”證明:將 m × n 棋盤形格子完全覆蓋的總方法數為費氐( Fibonacci )數列某些項的乘積。我們將把棋盤形格子完全覆蓋的所有方法數稱之為“蛇填充數” 由於這個問題自從 2004年 9 月 18 日被登在網站上後,還沒有人提出解答,於是引發了我們研究的興趣。首先,我們使用了將一個一個格子加到棋盤上的方法,並發現了 l × n 、 2 x n、 3 × n 棋盤形格子蛇填充數的一些規律。我們使用遞迴關係及數學歸納法來證明 l x n 、 2 x n , 3 × n 棋盤形格子蛇填充數的一般項。在接下來的研究中我們發現一個特別的方法,一次增加數個方塊 ‧ 最後我們證明了,m x n, ,棋然形格子的蛇填充數的一般項 ‧ 而且,我們也找到如何求出不規則棋盤形格子的蛇填充數。
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The Interplay of Iron and α-synuclein in mediating Neuroinflammation in Parkinson’s Disease
Neuroinflammation is implicated as a contributive factor to neurodegeneration in Parkinson’s disease (PD). Increased iron accumulation and deposition of -synuclein within Lewy Bodies in PD brains have been observed. It has been hypothesized that unbound iron is able to react with H2O2 to generate free radicals. Using the Divalent Metal Transporter-1 (DMT1) as a vehicle to transport iron into the brain, a DMT1 transgenic mouse model (DTg) was generated to recapitulate iron deposition in PD. The DTg was crossbred with the SNCA (synuclein) transgenic mouse to produce a DMT1_SNCA (BTg) mouse model to study the link between iron, -synuclein and neuroinflammation in PD. Our hypothesis predicts that iron exacerbates -synuclein toxicity by inducing larger inflammatory responses and consequently compromising functions of biomolecules. Our study shows that –synuclein triggers a low-grade inflammatory response by microglia and astrocytes while iron exacerbates -synuclein toxicity by eliciting immunological responses mediated by glia cells in the brain observed both in the DTg and BTg mice. Elevated levels of nitrated proteins were observed in the DTg, suggesting the role of iron in inducing nitrosative stress via upregulation of iNOS in glia cells. With the BTg mice, we hope to understand the effect of iron accumulation as an environmental stressor in aggravating -synuclein toxicity which may lead to the selective demise of dopaminergic neurons.
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本研究的目的在於探討螺旋狀剝皮對植物生存以及芭樂果實的影響。實驗的設計是將選擇的植株或其枝幹分成四組,分別施予環狀剝皮、螺旋狀剝皮一圈、螺旋狀剝皮三圈及不剝皮等處理。 研究結果顯示,螺旋狀剝皮不會導致植株死亡,且於處理部位下方會長出新的枝葉。芭樂果實經100 天的生長之後,不剝皮處理之枝幹長出的芭樂重量都在 300g 以下,而螺旋狀剝皮一圈之枝幹長出的芭樂有重達300-400g(5%)及 400-500g(5%),最重的達 490g;螺旋狀剝皮三圈之枝幹長出的芭樂也有重達 300-400g(占 7.7%)。此外,與不剝皮處理者比較之,螺旋狀剝皮也有助於高甜度芭樂比例的提升。 本研究成果若能成功應用在其他果樹上,有助於提高果農產收的經濟價值。 The purpose of our study is to examine spiral bark-stripping’s effects on trees, and observe what will happen with this treatment, especially in the survival of trees and fruit of Guava. The experimental design is as below. First, we divided tree samples or branches into 4 groups randomly, and then treated each group differently with girdling, spiral bark-stripping a circle, spiral bark-stripping 3 circles, or non-stripping on the trunks or branches. As a result, spiral bark-stripping did not cause death of trees. Instead, new green leaves grew below treated area. After 100 days of growth, the fruit of Guava treated with non-stripping weighed below 300 grams, while some fruit weighing above 300-400 grams(5%) and 400-500 grams(5%) grew on those trees treated with spiral bark-stripping a circle, with the heaviest of 490 grams. Besides, there are some fruit weighing 300-400 grams(7.7%) growing on those trees treated with piral bark-stripping 3 circles. The result shows that spiral bark-stripping, compared to non-stripping, promoted the proportion of high-sugar fruit. This study provides a possible way to increase the economic value of fruit harvest if applied to other kinds of fruit trees.
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打開水龍頭,水鉛直落到正下方的水平板時形成圓形水躍。我們實驗研究20<Nr<150 的低雷諾數圓形水躍的變因,探討圓形水躍半徑和流量、出水口高度、以及液體黏滯係數間的關係。改用高黏滯係數的液體(4:1 的乙二醇水溶液),鉛直落入板上方深h 的相同液體時,先形成圓形,h 漸大時形成環形圓紋曲面,再加大h,形成多邊形水躍,內外圍同方向旋轉,轉速ω;液中加水,黏滯係數高於及低於某定值,多邊形都消失,側面觀察,外圍液體作鉛直面旋轉。將水平板改置於旋轉盤上方,使高黏滯係數(4:1)的乙二醇水溶液鉛直落入板上方形成多邊水躍,逐漸加快旋轉盤的轉速至 ω 時,多邊形都消失;逐漸減少乙二醇的濃度,至完全用水實驗,亦有多邊形出現,我們認為;平板上方的液體的轉動是非圓形水躍的成因。When a jet of water falls vertically on to a horizontal plate, it spreads out rapidly in a thin layer until it reaches a critical radius at which the layer depth increases abruptly. This phenomenon commonly called the circular hydraulic jump. We study the variations of the circular hydraulic jump radius, as a function of volume flow rate of the jet, the drop height, and the viscosity of the fluid at low Reynold numbers (20<Nr<150). When a jet of ethylene-glycol mixed with water (the kinetic viscosity is 10 times of water) falls on to a horizontal plate which is immersed in the same liquid with height h. We find the circular state frequently undergoes spontaneous breaking at its axial symmetry into a stationary polygonal shape. Rather than displaying the weak angular deformation generally seen in fluids, the jump forms clear corners and edges that are often straight. Several of these polygon formations show consistency in height h. And we find the polygon structure rotates in a horizontal motion. When a jet of water falls on to a horizontal plate, and the plate is rotated by a motor ,we find the axial symmetry of the free surface of circular hydraulic jump is spontaneously broken a various number of cornered polygonal shapes. We study the number of corners as a result of the volume flow rate of the jet, the drop height and the viscosity of the fluid in the experiment. And the frequency of rotation of the plate is taking into consideration.
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