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「風笛」是台灣原住民鄒族的信號用具及祈雨法器,由一條繩子綁一支竹片構成。轉動風笛時,竹片會繞繩子自轉並拍打空氣而發出聲音,並有上下飛舞的現象。風笛產生聲音的原因,為竹片拍打空氣而造成的渦流共振現象;又由於繩子扭力大小及方向改變,使風笛的音調忽高忽低、響度忽大忽小、且竹片會在兩個平面上公轉,而有週期性變化。施力使風笛公轉轉速加快時,竹片自轉速率也變快,使其音調愈高、響度愈大;而繩愈短、愈粗時,竹片的公轉週期將愈短。The wind whistler was once used by Tsou aborigines as a tool for message transfer. It is composed of a string and a bamboo flapper. When swung around, the flapper spins, beats the air, and makes sounds. Moreover, the flapper flies up and down during the revolution. The spinning flapper beats the air, causes the vortex resonance phenomenon, and thus produces sound. As the twist torque and direction change, there is periodical variation in the sound volume, sound pitch, and the movement of the flapper, which orbits up and down at two planes. If given force to speed up its revolution, the flapper,s spinning frequency also increases, which makes the sound pitch higher and the sound volume greater. Besides, when the string is shorter or thicker, the flapper,s revolution period will be shorter.
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本研究是[對於正n 邊形A1A2…An邊上一點P(含頂點),想像自定點P 朝鄰邊發出一條光線,若依逆(順)時針方向依序與每邊皆碰撞一次,經一圈而可回到P 點,則此路徑稱為「光圈」。過程試著追蹤在正n 邊形內能形成光圈的光線行進路徑及其相關問題。
本研究令,且以逆時針得光圈來討論:
1.根據[光的反射原理],探討光圈之存在性,發現除定點P 在正2m 邊形或正三角形的頂點外,其餘皆有光圈。
2.將可形成光圈的路徑圖展開成[直線路徑圖]來探討。
3.由[直線路徑圖],觀察到形成光圈的光線行進路徑,可能存在下列情況: (1)不通過正n 邊形的頂點,且產生路徑循環與不循環問題。 (2)通過正n 邊形的頂點。
4.發現正2m 邊形光圈皆為[完美光圈]。
5.發現正2m+1 邊形光圈之路徑與有理數、無理數之特質有關。即當s 值為有理數時,路徑會循環;當s 值為無理數時,路徑不循環。
The research is about [on Point P (including the angles) on the side of regular polygons A1、A2…An , imagine the light goes from Point P to the closest side, then bumps each side sequentially counterclockwise. After going a circle, it’s back to Point P. The track is called “the circle of light.” I try to trace the light track of the circle of light and other correlative questions.]
In this research, we suppose,and we discuss the circle of light according counterclockwise direction:1.According to the light reflective principles, we discuss whether the circle of light exists or not. And then we discover that the circle of light really exists except when Point P is on the angles of regular triangle or regular 2m polygons. 2.Spread out the circle of light’s track to [rectilinear track.] 3.By [the picture of rectilinear track], observing there are two kinds of the circle of light’s track: (1)If the light doesn’t go through the angles of regular polygons, it can be a circulative track or a non-circulative track. (2)When the light goes through the angles, it stops. 4.We discover that all the circles of light in regular 2m polygons are [the perfect circles of light.] 5.We discover the circle of light’s track is correlative with rational numbers and irrantional numbers. When s is a rational number, the track is circulative, if s is a irrantional number, the track is not circulative.
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「外觀數列(The Look and Say sequence)」為依照外觀產生下一列的數列,第一列為「1」,第二列則描述第一列「1 個1」而為「11」,第三列「21」,第四列「1211」,依此類推。本研究針對外觀數列的各項數學性質作研究探討,並由此推導出外觀數列的一般式,即給定第n列就可知道該列的內容。
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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
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Human Computer Interface
Contains two human-computer interfaces. The first is an interface for blind people to perceive visual sensations using his tongue. Images from a webcam is processed with artificial intelligence software and is placed as a sensory matrix under the tongue. Currently the sensor placed on the tongue is about 8x8 pixels. The sight and the taste divide similar areas on the cortex so the blind person can adapt very quickly to the image sent on his tongue as an electricity matrix. Taste buds are the second sensor matrix after the eyes(as resolution) is based on the same principle of the Braile code but the information is received by tongue and it's proportional with the image from webcam and the person can receive more informations. The second interface follows the intent of motion detection of a person with disabilities. It is based on processing the neural signal of the brain taken by an handmade encephalograph and processing them with a artificial intelligence on computer. The project contains hardware and software. This project tries to suggest that the human computer interfaces can be made to support people with disabilities.
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這個題目是源自2003年的TRML思考賽的題目,原題目並不難,它只有用到簡單的排列方法,主要是討論 an 、bn 兩種數字的排列,其中 an 為滿足下列所有條件之N位數A的個數。
I. A中每一個數字為1或2
II. A中至少有相鄰的兩數字是1
而 bn 表示滿足下列所有條件的N位數B的個數
I. B中每一個數字為0或1
II. B中至少有相鄰的兩數字是1
以及探討an 、bn 與費氏數列cn之關係,其中 cn = cn-1 + cn-2 ,n≧3 ,c1=1, c2=2 。
其中 an 如果改成考慮為一數列,其值不變;而 bn 如果改為數列,那麼就不需要考慮0不能為首位數字的情況。如此,讓人聯想到一個用生成函數解的題目「一個N項數列,其中每一項只能是0或1或2,其中0和2永不能相鄰,求這個數列個數的一般式。」,因此,我們嘗試將這個題目改變它的要求繼續做下去,發現其中有某些規則,例如:不只是原來的11相鄰,甚至是排列其它種方式,都可能從其遞迴式看出它排列的意義,甚至這種排列數是可以用遞迴式求出來的。這提供了我們另一種求數字排列的方法,也是我們覺得有趣的地方。
在過程中我們初步得到以下結論:
This solution is according to power contest of 2003 TRML. It is composed of two number arrangements, an , bn .
First, suppose an is the total number conforming to the following rules.
I. Each number is 1 or 2 in A.
II. There is a couple of (11) in A at least.
Then, suppose bn is the total number conforming to the following conditions.
I. Each number is 0 or 1 in B.
II. There is a couple of (11) in B at least.
Furthermore , we give the thought to the relation among an , bn ,and cn (Fibonacci Sequence).
By the way, if an is changed to a sequence, and the result is the same. But if bn is to arrange number, we have to give thought to the fact that the first number can’t be zero. If it is a sequence, we don’t have to consider it.
The problem belongs to combinatorics. After we do this problem, we find not only original question but also other permutation can be understood by its formula. The problem provides us with other means to solve permutation and combination question. Then, we get the conclusion as follows:
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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
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Building Bridges with Water-The Floating Waterbridge
This paper describes the investigation of a fascinating physical phenomenon called the “floating water bridge”. Despite the fact that water is undoubtedly the most important chemical substance on earth, it is practically ubiquitous and it still represents one of the best explored substances, still not all characteristics are well-understood. There are some phenomena like the “floating water bridge”, which cannot be explained. If high voltage is applied to two beakers, which are arranged close to each other and which are filled with deionized water, a connection forms spontaneously, giving the impression of a floating water bridge. For the experiment discussed in this paper, two beakers with a diameter of 50 mm and a height of 80 mm are filled with triply deionized water. Platinum electrodes are submerged in the center of the beakers, one set to ground potential (anode), the other one on high voltage, up to 25 kV dc. Within the scope of this work, an experimental setup was developed, which enables measuring and demonstrating the most important parameters like voltage, current, length and temperature of the water bridge as well as the mass transfer between the beakers. In addition the correlation between the different parameters and the influence on the water bridge could be estimated. Once the beakers are separated, the bridge remains stable for several hours up to a length of 2.5 cm. With platinum electrodes and no electrolysis observed, a small current (≈300µA), a mass flow from anode to cathode and forces were measured. Pictures, taken with an infrared camera and a new developed method to record "infrared-videos", enabled to visualize the heat flow in the water bridge. Furthermore the conversion of energy and the dependence of charge and mass transfer could be estimated roughly. In the course of the investigations it was also tried to prove the water bridge with other liquids like castor oil, olive oil, a mixture of glycol and water as well as tap water - for some of them for the first time. Supplementary the experimental setup was varied by using different electrodes with different sizes and different material as well as beakers of different sizes and materials. In addition, a qualitative explanation was developed. The results of this work enable a better understanding of the floating water bridge and provide a basis for further research as well as for development of future practical applications. One of these applications could be an improved waste water treatment process.
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給定一平面E,A為平面上一點。取r>0,則我們知道到其距離為定值的點形成一圓,而A為此圓圓心。如果把A改成一平面圖形,則到其距離為定值的點形成的集合會是什麼樣子?類似地,給定平面上兩焦點F1及F2在平面上,則到其距離和為定值的點形成橢圓。同樣的,若把F1及F2改成平面圖形,其圖形會是什麼樣子?藉著GSP的輔助,到目前為止,我們得到了以下的結果: \r 1. 給定一平面E及此平面上的一個凸多邊形, 我們描繪出在此平面上到此凸多邊形之距離為定值的點所形成的圖形。\r 2. 設F1和F2分別為平面E上之點或線段或多邊形(未必是凸多邊形),我們利用包絡線描繪出所有滿足d(P,F1)+d(P,F2)=k(k夠大)的點所形成的圖形。 \r 3. 設C1,C2為平面E上之兩圓,我們討論所有滿足 d(P,C1)+d(P,C2)=k\r (k夠大)的點形成的圖形並討論其性質。 \r 4. 設L1和L2分別為平面E上之兩線段,我們討論所有滿足d(P,L1)+d(P,L2)=k(k夠大)的點形成的圖形並討論其性質。 \r 5. 設A為平面E上之一點,Γ為平面上一凸多邊形,我們討論所有滿足d(P,A)+D(P,Γ)=k(k夠大)的點形成的集合並討論其特性。 \r 6. 藉由和圓作比較,我們研究了變形圓的光學性質;而對變形橢圓也做類似的討論。\r Let E be a plane and A a fixed point on E. Given , it is known that all of the points on E with distance to 0r>rA form a circle and the point A is called the center of this circle. What is the corresponding graph if we replace the point A with a set (for example,a segament or a polygon) contained in FE? Similarly, what is the case when we modify the two focuses and in the definition of an ellcpse to sets and (or example,two segments or two polygons) contained in 1F2F1F2FE ? Taking advantages of GSP and analytic geomety, we research related situations and so far we have obtained the following results:\r 1. Let Γ?E be a segment, a convex polygon or a circle , etc. and r>0 be fixed. We sketch the graph of points on E with distance r to Γ and study properties of such graphs.\r 2. Let F1 and F2 be singletons, line segments , polygons(may not be convex), or circles,etc., on E Taking advantage of envelopes, we sketch the graph of those points P on E satisfying d(P,F1)=k(K>0 is large enough).\r 3. Let C1 and C2 be circles on 1C2CE. We sketch the graph of the points P on E that satisfiy d(P,C1)6d(P,C2)=k (k>0 is large enough) and study properties of this graph.\r 4. Let L1 and L2 be two line segments on E and be a large enough constant. We sketch the graph of points P on E that satisfy d(P,L1)+d(P,L2)=k(k >0is large enough) and research properties of this graph. 0k>\r 5. Let A?E and be a convex polygon on ΓE. We sketch the graph of points on E that satisfy d(P,L1)+d(P,L2)=k(k>0 is large enough) and research properties of this graph.\r 6.We compare the optical properties of metamorphic circles with circles and we deal with metamorphic ellipses similiarly.
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新網路模式對抗無尺度流行病傳染A New Network Model to Fight Against Scale-Free Epidemi
流行病的傳染如同一個無尺度網路,但有一些特殊特性在發展一套新傳播模式時,是需要被詳加考慮的。我採用時間位移(t 與ti 分別以t?(ti?1)與ti?(ti?1)來取代)至無尺度網路模式中,再引入一個非連續強力函數H(t; ti?1, L+ti?1)來描述流行病傳播的特定時段與強度,並重新定義機率p 為無效傳染率。之後,我建立了新模式「無尺度流行病模式」-SFE-1與SFE-2。模擬六種病原的傳染途徑,結果證實SFE-1與SFE-2模式是正確與確切可用。案例研究結果,顯示傳染強度H可為固定值或為變數;p可以是一固定值、雙固定值或為新增病例的函數。更進一步解析美國AIDS病例在不同族群與行為上的差異,獲知亞裔/太平洋裔與印第安人/阿拉斯加人的H值低於其他族群,其原因可能是由於小的族群具有較高的接觸所致。異性性接觸的H值低於其他,顯示性交易是傳播HIV的主要途徑。SFE-1與SFE-2模式也可被用在流行病的預測上,因為SFE-2使用已知值而非估算值,所以SFE-2模擬結果較佳;但是SFE-1更可以明確提供一個流行病在失控或控制下的預測結果。無尺度流行病模式可以協助所需警戒的程度與政策決定的計畫結果。因此在幫助政府評估社會經濟成本與健康憂慮上是一個有用的工具。所以我提出一個確切可行的對抗無尺度流行病傳染新方法,並詳細說明運作流程。The course of epidemics resembles a scale-free network, but some specific elements should be considered in developing a new model. I introduced a time shifting (replacing t and ti by t?(ti?1) and ti?(ti?1)) and a discontinuous forcing function H(t; ti?1, L+ti?1) into the scale-free network model to fit the specific period and intensity of the infection, and redefined the probability p as an invalid infection rate. Then I proposed the new Scale-Free Epidemic Models, SFE-1 and SFE-2. The simulation results of six types of epidemic transmission showed that the SFE models were accurate and useful. In the case studies, the results showed that H were constant or variable, and p were a fixed constant, a dual constant, or a function of new addition cases in the epidemic periods. The further studies for comparisons of the difference races/ethnics and the difference transmission category of AIDS cases in USA were analyzed. The H value for Asian/Pacific and Indian/Alaska Native race were lower than others, it may be due to small clusters with constant high contact rates. The H value for heterosexual contact was lower than the others, indicating that whoredom was the main transmission for HIV. Both SFE models can be used to predict epidemics, SFE-2 is better than SFE-1 due to SFE-2 using given indices and not conjectured values, but SFE-1 can more clearly suggest results of epidemics when under control or not. SFE models can help the government to determine the level of caution needed and the projected results of policy decisions. They are useful tools in assisting to balance socio-economic and health concerns. I hereby propose a new method to fight against epidemics with detailed procedures of using the SFE models.
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終極目標-萬獸之王曲軸、連桿、後腳組合的探討
在這個研究當中,我們設計並製作完成一部手工機械車模型。實驗該車曲軸分別在 0.5、1、1.5、 2 、2.5、 3 公分,連桿在9、10、11、12、13 公分,後腳在 3、3.5、4、4.5、5 公分各種組合對速度及拉力所產生的影響。並用 GSP(The Geometer’s Sketchpad) 繪圖模擬來驗證其結果之可行性。在拉力部份,原始實驗(前後腳底加日式止滑墊)由於與底面積摩擦力不足,實驗數據無法忠實呈現拉力。於是我們決定在軌道上貼砂紙並用以下四種方式來做實驗(1)在四腳上各加一個電池 (2)在四腳上加電池,在後腳底貼上橢圓形橡膠軟墊 (3)四腳加電池,後腳做關節且加大腳底面積 (4)四腳加電池並鋸短四腳,且加大腳底面積。實驗數據顯示在曲軸、連桿、長度改變及後腳孔位置高低改變時,拉力會隨之增加或減少。本研究歸納出下列結論:曲軸越短,速度越慢,拉力越大。連桿越短,速度越快,拉力越小。後腳孔位置越高,速度越快,拉力越小。
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傳統的畢氏定理三元二次不定方程x² + y² = z²有一組漂亮的整數解為(m² - n²、2mn、m² + n² );中國數學家嚴鎮軍、盛立人所著的從勾股定理談起一書中記載四元二次不定方程x² + y² + z² = w²的整數解為(mn、m² + mn、mn + n²、m²+ mn + n² ),這組解被我們發現有多處遺漏,本文以擴展的畢氏定理做基礎修正了他的整數解公式,並推廣取得N 元二次不定方程的整數解公式。
There is a beautiful integer solution formula for the Pythagorean theorem equation, x² + y² = z² , such as (m² - n² , 2mn ,m² + n² ). The “m" and “n" of the solution formula are integer number. A book written by two Chinese mathematicians, Yen Chen-chun and Sheng Li-jen who expanded the Pythagorean theorem equation to the four variables squares’ indeterminate equation, x² + y² + z² = w² . They claimed that they found its integer solution formula, such as (mn , m² + mn , mn + n² , m² + mn + n² ) for any integer “m" and “n". But we found it losses many solutions. This paper corrected their faults due to the expanded Pythagorean theorem built by ourselves. Further more, we derived a general formula of N variables squares’ indeterminate equation. Now, we can get integer solutions of the equation, (for all natural number “n") easily by choosing integers m1 , m2 , m3 ,……, mn−1 up to you.
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