全國中小學科展

出國代表作品

外觀數列

The Look and Say sequence is produced by describing the appearance of the previous row. For example, start with “1,” which can be described as “one 1,” and therefore the second row is “11,” which is "two 1s," making the third row “21,” the fourth row “1211,”and so on. The main goal of this study is to work out the exact formula for this sequence, which means given the row number n, we can know at once what the n-th row is without having to start from the first row and doing the look-and-say iteration for n-1 times. Some of the methods used include dividing groups, repetition and cracks. The formula we derived speeds up the calculation and gives us a better understanding of the look and say sequence.「外觀數列」為依照外觀產生下一列的數列,第一列為「1」,第二列描述第一列「1 個1」而為「11」,第三列則描述第二列「2 個1」而為「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。我們運用了分組、重複性以及裂縫的方法分析數列,最後得到了其一般式,此一般式有助於運算速度的加快以及我們對數列性質的了解。

隨機物體轉移過程的實驗時間之初探

有二系統A和B,A中一開始有2k個物體,,B中有0個物體。在一個單位時間內,兩系統可以互相轉移最多一個物體。當B中物體的個數為 i-1,i∈{1,2,...,k+1},我們稱其為狀態 i,從狀態1﹝初態﹞開始計時,到達狀態 k+1﹝相同態﹞便即刻停止實驗,經過之時間為一隨機變數T,稱之為實驗時間。問當兩個系統的物體數剛好相等時,經過的實驗時間之分佈為何?本文將以上述問題為核心,分別探討不同條件下系統的實驗時間所反映出來的現象,如機率、期望值、變異數等等。 Define two systems, A includes 2k objects, and B has none. They can transfer at most one object from one system to another in a time unit. When the number of objects in B is i-1, i∈{1,2,...,k+1} , we say the system is at state i. As soon as system transfer form state 1 ( initial state ) to state k+1 ( the same state ), the experiment stop. Random variable T, called the experiment time, is the time before stop. What would be the distribution of the experiment time if all systems have the same amount of objects within? This article will focus on the described question and discuss what property the experiment time of the system under various conditions has, such as probability, mean, and variance.

氣泡在黏滯性液體中的運動

本研究目的在探索不同大小之氣泡在不同黏滯性液體中運動情形。實驗結果發現大氣泡向上運動的速度較大,其下方會漸漸向內凹。並且觀察到氣泡間結合時的相互作用:氣泡在相同黏滯性膠水中上升時,若下方氣泡體積較大,其較快的速率會使距離縮短。此時小氣泡的下半向內凹,大氣泡的下半則向外呈現流線型尖端並且在接近小氣泡時速率增加,最後與小氣泡結合。若上方氣泡體積很小,與下方大氣泡的距離縮短至相互貼合,小氣泡會先停留在大氣泡的上半表面,再沿大氣泡表面下滑至大氣泡的下半才與大氣泡結合。This research traces the motions of bubble with different volume in viscid liquid. The experimental results show that the bigger bubble rises at faster speed. The shape of the small bubble is round. As the volume of the bubble increases, it turns hamburger-like. And if the bubble is big enough, its underside would be concaved. In viscid liquid, the speed of the bubble is not smooth but waved. The smaller the bubble is, the more the variation in speed is. The interaction of two bubbles is also studied. There are two types of the combination of two bubbles. While the big one closes to the small one, it is accelerated. The underside of the small one becomes concave. And the big one becomes streamline shape. If the difference in volume between two bubbles is significant, the small one slides along the surface of the big one, and goes into the concave beneath it, then combines with it.

竹嵌紋病毒及其衛星核酸5'端非轉譯區與複製競爭關係之探討

RNA 病毒在複製過程中容易產生錯誤,導致其族群具中有很大的遺傳歧異度,累積的錯誤再加上選汰的壓力造成往後之變異。由於RNA 基因體之病毒變異較大,使得RNA 病毒在單一寄主上具有quasispecies 的特性,提供病毒產生新基因體的機會以適應環境或演化成新病毒。例如流行性感冒病毒與之前造成恐慌的嚴重急性呼吸道症候群病毒(severe acute respiratorysyndrome,SARS)以及禽流感病毒 (avain influenza virus) 皆為RNA 病毒,意味著RNA 病毒知不穩定性,並容易造成一些目前我們無法及時反應的危害。大部分的植物病毒又為RNA 病毒,本研究將以竹嵌紋病毒 ( Bamboo mosaic virus , BaMV )及其衛星核酸 (satellite RNA, satBaMV)為材料,進一步探討核?酸序列之變異對其族群在複製競爭上的影響。

酒杯發出之音符

When you draw a wet finger around the edge of a half filled wine glass, a sweet musical sound comes forth. The pitch of this sound is directly correlated to the amount of liquid in the glass- the higher the height of the liquid is, the lower the frequency is. It means that the shorter the air column in the glass is, the lower the frequency is. This phenomenon differs from the variance in pitch in a wind instrument. In a wind instrument such as a flute, the shorter the air column in its chamber is, the higher the resulting pitches are. In order to study the wine glass phenomenon, we used a piezoelectric crystal loudspeaker connected to an oscilloscope. We recorded the resulting data by using a digital video recorder to capture the images of the waveform of sound, and than analyzed the waveform by using the computer. Our conclusions are as follows: 1. The frequency of sound thus produced was the same whether we draw our finger around the rim, or we strike the glass rim. The higher the height of the liquid is, the lower the frequency is. But the frequencies vary when we strike the glass and when we blow on the edge. 2. When we used a glass without liquid in it, the frequency emitted when we drew our finger around the edge, this frequency varied inversely as the cube root of their weights. 3. In a glass with liquid, the emitted frequency did not have any correlation to the weight of the contents. By taking two identically filled glasses and placing in each a solid object of the same size but different weight, we were able to see that there was no change in the frequency emitted between the two glasses as long as the height of the liquid remained constant. 4. According to “The Flying Circus of Physics”, if we tap the side of a glass of beer, because of the air bubbles in the beer, the frequency emitted will be lower than that from a glass of pure water. This is according to the book, because the speed of sound is lower in air than in water, therefore the speed of sound in an air-water mixture would be lower than in pure water. The resonant frequencies of the mixture will also be lower. However, in our experiment, we discovered that\r when the glass contained air bubbles, the frequency emitted higher. Our explanation is that the sound emitted since the rim of the glass oscillated transversely, the frequency depends only on the retard of the rim and that the frequency is independent of the speed of sound. The intention of this research is to clarify the many misconceptions of this interesting phenomenon.以溼的手指在玻璃酒杯邊緣摩擦,會有悅耳的聲音,而且頻率會隨著內裝液體減少(空氣柱變長)而變高,這種變化與管樂器隨空氣柱的變長而音調變低不同,為了研究它的原因,我們利用壓電晶片喇叭連接到示波器上,並且利用數位錄影機錄下示波器上的訊號,再以電腦分析出瞬間的頻率,結果發現:一、摩玻璃杯與敲玻璃杯,杯所發出之頻率相同,都是所裝液體愈多發出之頻率愈低。但敲玻璃管與吹玻璃管所發出之頻率不同。二、不裝液體之高腳杯,摩擦時所發出之頻率與重量之立方根成反比。(與鐘相同)\r 三、裝液體之高腳杯發出之頻率,不再與總重量有關,而是與液體之高度有關,保持液體高度不變,即使在杯子中央加入不同重量之固體,杯子振動頻率還是不變。若改裝不同密度之液體,則密度愈大頻率愈低。四、在“The Flying Circus of Physics”書中提到輕敲裝有啤酒之杯時,會因杯中含有氣泡而聽到較低之音調,書中解釋是”空氣中之音速低於水中之音速,混有空氣之水中音速變低,其共振頻率也會降低。”但我們的實驗結果是有氣泡時頻率反而高。我們的解釋是杯子所發出之聲音是由於杯面之振動也就是杯壁的橫向振盪,振盪頻率與液體對杯壁之阻尼有關,但與液中聲速無關,密度愈大之液體阻尼愈大。有氣泡時接觸杯壁之液體變少,阻尼較少所以頻率高。希望本研究能使大多數人對這有趣之現象不再有誤解。

DNA Detection by EGFET using GaN Nanowires Gate

DNA感測器近年來蓬勃發展,應用層面包括基因工程,醫學及藥物的開發等,然而目前較常使用的感測方法,需要繁瑣耗時的標定過程,且所使用的化學藥劑對環境容易造成傷害,鑒於以上方法的不完善處,我們決定設計一套新的感測系統,此研究結合了氮化鎵奈米線(GaN Nanowires)及延伸場效電晶體(EGFET)的優點,成功的發展出創新的DNA感測系統,氮化鎵奈米線的高生物匹配性及高感測面積,能有效提高靈敏度,延伸式場效電晶體的設計,史感測器具由免標定及時感測的特性,且易於組裝及操作,我們將探針DNA(probe DNA)修是在氮化鎵奈米線作為之延伸閘極上,由於DNA在中性水溶液中帶負電,且DNA之間具有強烈的互補特性,因此當目標DNA(target DNA)與探針DNA接合,形成雙股DNA,氮化鎵奈米線(閘極)的表面電位即會有所變化,並造成FET特性的改變,藉由此性質及能成功感測DNA,研究結果顯示,此研究所發展出的DNA感測器,愈有相當高的靈敏度(10-18),相較於其他以FET技術所設計出的DNA感測器,靈敏度提升了三個數量極,此外此感測器亦具有高選擇性,即使單一鹼基對的突變也能成功辨別;-hybridization based detection techniques are widely developed due to their promising applications in genetics, medicine and drug discovery. However, current DNA detection techniques based on labels or reagents are time-consuming, environmentally-harmful and complex to implement. In this study, we have successfully demonstrated a label-free extended-gate-field-effect-transistor (EGFET) sensor utilizing a GaN-nanowires electrode with DNA probes immobilized, capable of specific DNA sequence identification. The principle behind the design is based on the change in surface potential and charge transfer after hybridization. GaN nanowires, being bio-compatible, provide direct transfer path and high surface area, thus offer an unprecedented opportunity of DNA sensing with high sensitivity. In addition, our EGFET design facilitates easy assembly and operation of DNA detection. Comparative studies on complementary and non-complementary DNA were performed to verify the specificity of the sensor. By adapting GaN nanowires structure, the assay time of DNA was shorten to within thirty minutes. Moreover, our sensor displayed an ultra-high sensitivity in the level of attoM: three orders of magnitude higher in resolution than that of other FET-based DNA detection methods.

推著離子跑

在本次實驗中,我們發現溶液中的帶電離子,會因為離子團的熱運動,和電偶極的庫倫吸引力(electric dipole)的交互作用下,使得電解質溶液的I-V curve(電流-電壓 曲線),具有類似磁滯曲線(Hysteresis curve)的效果,同時我們運用光學干涉的原理,證實此時在電場作用下,離子團會互相順著電場方向作條列鍵結,而加熱實驗也證實,熱運動會使溶液的I-V curve(電流-電壓 曲線)變的不一樣。另一方面,我們也發現,在給予電解質溶液一外加的衝擊電壓時,該溶液的電荷分布,?會因為彼此的互相擠壓以及自由擴散的作用下,而形成一震盪分布,其所顯現出來的,則是電壓的震盪變化。最後由於震盪波紋的變化,在起始時與中段之後有著明顯差異,我們對此變化提出看法和證實,相信內容是精采可期的! In this experiment, with the interaction of the heating action of ionic atmosphere and electric dipole, we find that ionic in the liquor makes the I-V curve in the electrolyte liquor show up with the effect similar to Hysteresis curve. Meanwhile, we practice the principle of interference to prove that at this moment, under the influence of electric field, ionic atmosphere will connect to each other in line following the direction of the electric field. It is also proven that in the heating experiment, heating action will make I-V curve in the liquor different.On the other hand, we also find with extra electric impact, the charge distribution of the liquor will form a oscillation, that is, the changes of the voltage oscillation under the inter-collision and the free spread. We offer our viewpoints and proofs about the obvious changes of oscillation wave in their beginning stage and after their middle stage. We believe that the marvelous content is surely worth of your expectation.

「渦」藏「聖」機--以渦流脫離重新詮釋聖嬰發生的原因

If we place a block in continuous, steadily flowing water, some periodic eddy currents will appear behind it. In my report, I would like to introduce a new way to explain how the periodical movement of eddy currents would help to triggering El Nino. According to my experiment, these eddy currents have a certain life cycle, and the eddy current give a force, which drag water form the area they just went by. It will cause water level became lowest for a period of time. These phenomena are also shown in the real data of “Sea Surface Height Anomaly”, it is a quiescence period, and then changes into the highest one it is interesting that highest one always follows by the starting of El Nino. Another important result from my experiment is that, in the same fluid, the frequency of eddy currents is controlled by 2 variables: Size of the block and velocity of the flow, From this result, then get the frequency of eddy current-occur every 3.2 years. It is just correspond with frequency of historical data the El Nino from the 70’s to the present. 本報告嘗試以南極繞極環流在南美洲南端產生週期性渦流脫離的現象來解釋聖嬰的發生根據水槽實驗的結果,水流在通過障礙物後渦流脫離瞬間,會形成一水位低的空區,之後在周圍的水大量湧入,水位突然升高,並有一段時間的振盪。另外,實驗結果也顯示,渦流形成和脫離頻率大致上和注水流速成正比,且和障礙物的大小成反比。根據此結果,對照實驗結果,我認為1993 年3-4 月,1996 年1-6 月及2001 年7-10 月三個「海平面高度異常」的最低值密集帶,此極可能是渦流脫離的時段。且對照「海平面高度異常」實際資料後,發現「海平面高度異常」的「最低值密集帶」後均伴隨水面「寧靜期」,接著就出現周圍暖水流大量湧入的「最高值密集帶」,此時南美洲東南側海水溫度驟增,接著馬上接續著聖嬰的到來。「海平面高度異常」分析的結果,指示渦流脫離的「最低值密集帶」和顯示著聖嬰到來的「最高密值密集帶」間約間隔半年左右。我們推算水的史托爾數約為1,以這個值代入實際南極繞極環流通過南美洲南端,得到渦流脫離的頻率約每3.2 年一次,和長期聖嬰發生的平均頻率非常接近。

Equtatetor-新一代智慧型數學處理器

此研究的目的是要設計出一套完整編輯顯現數學式、加以計算,並求出解的一套方法與成品。而這項工作的執行者,在此稱之Equatetor 。一般的數學式子,若要計算的話,普通的計算機是不足夠的。原因是它們沒有辦法表現出數學式的「原貌」,例如分號、指數、函數、根號等數學符號混在一起時的情況。於是,我便擬定了一個研究,希望設計出一套更方便且實用的方法。換句話說,我要設計出一個功能強大的工程計算機程式。其中,自然牽扯到數學式子的顯現方式(以MathML 實現),以及計算機科學的演算法及資料結構。我主要的目的有四:(1) 顯示數學式(2) 方便編輯數學式(3) 計算數學式(4) 處理可以以不同形式輸出解答的計算(如輸出分數、根號、函數解等)。研究結果中,成功地運用XML 中的MathML 與二分逼近分數等演算法及若干資料結構,達到了以下實用的幾點:(1) 結構化的數學式編輯(2) 完整地顯示數學式(3) 正確運算並輸出運算式的答案(4) 提供一般數學形式之解(非小數之解);The object of this study is to design a method and processor which is able to edit, display a mathematical expression representing a number, calculate and output the answer. The executor of this task is called Equatetor. Normal calculators are not adequate for this kind of task. The main reason is that they can’t reveal the original expression, such as fractions, radicals, exponents or mathematic functions. Therefore, a simple and convenient method is needed. To perform the possible way of handling those tasks, a computer program has been written. Several techniques were used, such as MathML, computing algorithms, data structures, and so on. Following are main purposes: (1) Displaying mathematical expressions. (2) Editing mathematical expressions simply. (3) Calculating mathematical expressions. (4) Outputting the answers(in different expressions). And the achievements:(1) Structured methods of editing of mathematical expressions. (2) Displaying mathematical expressions completely. (3) Calculating mathematical expressions precisely. (4) Offering answers in different expressions.

極速火龍-利用軟片顯影法觀測氫爆的火焰傳遞

用塑膠軟管作為氫爆安全反應器,從封閉端點燃氫氧預混氣,管中火焰\r 傳遞快速,肉眼難以觀察,因此研製「氣爆顯影記錄器」來觀測,如下圖,\r 光纖導引偵測點的火光至暗箱,記錄於高速旋轉的軟片,從光電轉速計讀取\r 轉速,軟片沖洗後量測各顯影間距,可得火焰位置與時間的關係圖,量測時\r 間最小刻度可達2. 2 微秒。\r 解讀軟片的顯影,得知氫爆初期,火焰加速傳遞,大部分在25cm 位置\r 左右,火焰的速率出現急速飆升(爆燃轉變為爆震),而且火光亮度也急速升\r 高,有時火焰速率出現飆升過高,再回降趨於穩定?的現象,在50 cm 位置\r 左右,火焰進入等速傳遞階段,此階段有穩定的火焰模型,火焰頂端的亮度\r 最高,往後亮度遞減。