全國中小學科展

三等獎

省錢大作戰-探討籬笆價格和所圍面積的關係

本研究探討在給定範圍的面積下,以最省錢的方式用籬笆圍出最大的矩形土地,其中矩形的邊長為正整數,且矩形對邊使用相同單價之材質的籬笆,但相鄰邊使用不同單價之材質的籬笆。我們希望透過轉換,將單價不同的情況回歸到單價相同的情況,以便完整的解決這個問題。\r 藉由改變邊長,將 轉換成 ,使問題轉換成相鄰邊之單價相同的情況;但是經過運算找出的最佳解 轉換回 後卻不一定符合「整數邊長」的要求(即 和 不一定是整數)。為了解決這點,我們重新以不同的角度探討單價相同的情形,以找出整數的最佳解。\r 最後我們發現,若 和 切線斜率的差值大於或等於1,則 坐標愈近 的解愈佳,而在差值小於1的範圍內,我們提出一個檢驗法,可以找到整個問題的最佳解,同時讓此最佳解 轉換回 後仍符合「整數邊長」的要求,進而解決問題。

樂器聲波之探討(The Study of A Sound Wave on Musical Instruments)

演奏樂器時,是使發聲體產生駐波而發出各式各樣悠揚的聲音及音調;樂器主要分成振動體(發聲體)及共鳴器兩部分,依發音方式分為弦樂器(使弦振動產生駐波)、管樂器(利用空氣柱振動產生駐波) 及打擊樂器(利用板、膜或磚等彈性材料的固有頻率振動產生駐波)。聲音有三要素:振幅、頻率及波型,響度取決於振幅大小、音調與頻率有關、波型則由不同的頻率及響度組成。樂音多變的主因是音色及音調。音色是發聲體的發音特性,取決於該發聲體的聲波波型。音調即聲音的高低,與發聲體的振動頻率材質息息相關,頻率愈高,其音調愈高,而樂曲中的音階高低則是由音調高低所構成。樂曲的製作及演奏必涉及到律制,從駐波的產生、律制的探討、頻率的測量和琴鍵的振動模型建立與波形的觀察,我們使用計頻器、示波器及有限元素ANSYS 軟體、數學計算Mathematica 軟體,我們設計一系列實驗,企圖對樂器聲波操作技巧有更進一步的認知。從實地走訪樂器製造廠,了解到設計與改良仍是樂器工藝家重要課題,本文的實驗方法可提供大型演奏會現場調音、樂器調音師或樂器工藝家設計製造樂器時參考用,對於發展文化產業期待提供更經濟與實用的建議。;Playing musical instrument is to make sounding part produce stationary wave so as to give off various gentle sounds and tones. According to different modes of sound producing, musical instruments which comprise vibrator (sounding part) and resonator can be divided into stringed instruments (which vibrate the strings to produce stationary wave), wind instruments (which produce stationary wave with vibration of the air column) and percussion instruments (which produce stationary wave with natural frequency of boards, films or bricks). Three Essentials of sound include amplitude, frequency and waveform, in which the amplitude decides the volume, tones are related to frequency and the waveforms are composed of different frequency and volume. Various musical sounds are mainly due to different timbres and tones. Timbres, sounding characteristics of sounding part, is decided by waveform of the sounding part. Tone means pitch of the sound and is closely related to vibrating frequency of sounding part. Higher frequency makes higher tones and pitch of a musical scale is decided by different tones. Music composing and playing is necessarily connected with music temperament including producing of stationary wave, discussion of temperament, measurement of frequency, establishment of vibrating mode of keys and observation of waveform. We adopted frequency counter, wave inspector, ANSYS software and Mathematica software and designed a series of experiment to get further knowledge of technique of handling musical instrument wave. After visiting musical instrument manufacturers, we learnt that design and improvement are still the essential subjects for instrument craftsmen. Experimental method in his article can provide reference for on-the-spot tuning of large concert, musical instrument tuner and musical instrument designing and manufacturing by craftsmen, and more economic and practical suggestion for cultural industry development.

Poly(ADP-ribose)polymerase-1 對細胞內DNA damage修補的調控

Poly(ADP-ribose) polymerase-1 (PARP-1)是一個細胞核內的酵素,它可以被因DNA damage\r 而形成的DNA片段活化,並將NAD(+)上的ADP-ribose轉載到結合蛋白質。這些結合蛋白質對\r 於DNA的合成、DNA的修補、以及細胞週期的調控都有關係。因此,PARP-1被認為是維持基\r 因完整性的重要角色。根據初步的研究,抑制PARP-1的活性對許多疾病的治療都可能有效,\r 其中包括癌症、心臟病、中風、糖尿病、發炎以及反轉錄病毒的感染。然而,以藥物抑制一\r 個對DNA修補這麼重要的酵素會有什麼潛在的問題呢?為了要得到解答,我們需要進一步了\r 解PARP-1在DNA damage反應的機能。在這一份報告中,我製造了一個失去活性的PARP-1突變\r 種,即E988K。經過對E988K詳細的研究,我將比較及分析PARP-1野生型與E988K之間不一樣\r 的互動蛋白質,希望能對PARP-1所控制的DNA修補有更進一步的了解。\r \r \r Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme activated by DNA strand breaks\r during DNA damage response and catalyzes the transfer of ADP-ribose units from the substrate NAD(+)\r to acceptor proteins. These acceptor proteins involve in modulation of chromatin structure, DNA\r synthesis, DNA repair, transcription, and cell cycle control. Thus, PARP-1 is believed to play an\r important role in maintaining genome integrity through modulation of protein-protein and protein-DNA\r interactions. PARP-1 has been the target for design of inhibitors for over twenty-five years. Inhibitors of\r the activity of PARP-1 have been claimed to have applications in the treatment of many disease states,\r including cancer, cardiac infarct, stroke, diabetes, inflammation and retroviral infection. However, are\r there potential problems associated with inhibition of this DNA-repair enzyme? To answer this question,\r we need to further understand the biological function of PARP-1 during DNA damage response. In this\r report, an enzyme dead mutant (E988K) of PARP-1 was generated. Detailed studies of E988K show that\r E988K could be used in the following studies. Compare and identify the different associated proteins of\r PARP-1 wild-type and E988K will shed light into the molecular mechanism of PARP-1-mediated DNA\r repair.

溫變性轉(孵化條件對宮廷雞性別的影響)

目前生物學知識認為雉科鳥類的性別,在卵受精後即決定(WZ型),不受環境的影響,但是在本組一連串的實驗中發現,雉科鳥類的性別與孵化的溫度變化有非常大的影響,一般宮廷雞的孵化條件在濕度55%RH及溫度98℉~99℉,在此孵化條件下宮廷雞的子代♀:♂=1:1,若溫度降為97℉的孵化條件下所得子代♀性佔93%,倘若溫度升高為100℉的孵化條件下所得子代♂性佔92%,可見在比正常孵化溫度高的環境下宮廷雞的受精卵會轉變為♂性,而比正常孵化溫度低的環境下孵化的宮廷雞受精卵卻會轉變為♀性,本實驗續做了六代,結果大致相似,由此可以證明控制孵化溫度可以改變宮廷雞的性別,這一行為,可能與Z染色體上一個溫度依賴型的連鎖基因(DMRT1)之表現有關。 ;The temperature of hatching can affect Chinese silkys's sex It is now established that the sex of Pheasants is determined when the egg is impregnated, rather than by environmental factors. However, in a series of experiments, we find that the sex of Pheasants is strongly related to the temperature of hatching. In the normal hatching condition (humidity:55% RH ,temperature: 98.5℉), the ratio of female and male offspring of Chinese silkys is 1:1. If the temperature is lowered to 97℉, the female offspring occupies a proportion of 93%. If the temperature is raised to 100℉, the male proportion will reach 92%. We can thus derive the conclusion: the impregnated eggs of Chinese silkys will be transformed to male at a temperature higher than the normal one, while a lower temperature than the normal one will cause the impregnated eggs to be female. The experiments have been conducted through six generations of Chinese silkys, and the results are practically the same. This indicates that temperature changes can affect gender, This may be related to a Z-linked of DMRT1 gene on the DNA, which is temperature-dependent.

波動奇蹟—皂膜與皂水共振模式之研究

本研究探討肥皂膜與肥皂水的共振現象。在肥皂膜共振方面,我們以實驗探討皂膜的共 振模式與頻率的關係;並配合共振理論模型求出薄膜厚度,再與體積密度-厚度測量方法比 較。而又發現皂膜在共振時,皂膜保存時間較平常久,故進行皂膜生命期與頻率、強度的關 係。在進行肥皂膜實驗時,肥皂水滴落在喇叭上,振動出奇特的形狀,進而探討皂水共振的 特性並嘗試建立其數學模式。 ;The research is about the resonance of soap film and soapsuds. For the resonante of soap film, we tried to find out the relation between the resonant pattern and frequency by experiment; according to the resonante model, we measured the thickness of soap film, which was compaired with volume-dencity method. We found that the life-time of the resonant soap film is longer than the normal one, so we proceeded to study the relation between the life-time, frequency, and power. We observed special resonant pattern while the soapsuds fell down on the speaker. So we studied the characteristics of resonant soapsuds, trying to make the mathematical pattern of resonant soapsuds.

口琴簧片振動與氣流的影響

本研究主題在測量口琴簧片受到各種氣流因子影響後,所產生音色、音頻等變化之探討。在過去我們認為,一片簧片不論如何吹奏,其發出的頻率皆相同。但是事實上,演奏家控制氣流的強弱、方向、渦流等,便可吹奏出多樣的音頻。探討形狀因子對簧片頻率的影響,如:長度、寬度、厚度對頻率所造成的影響。自製口琴,利用變壓器控制送風機風速。探討氣流因子對簧片主頻之影響,利用各種不同的自製吹嘴,改變風速、角度、渦流…等,找出可能使簧片改變頻率的氣流因素。實驗結果發現改變風速會影響簧片主頻的變化,風速越大,頻率越大,為一條平滑線。但並非一直都會上升,當簧片頻率上升至某一極限,便無法再利用風速使頻率上升。例如實驗四吸音標準狀態下,風速大於8 Kt 後,頻率一直停在429Hz。在外加障礙物時(模擬吹奏舌頭時隆起)和標準狀態(正常零度入射)下頻率比較吹音和吸音有明顯的差異。吹音時,同風速下,其頻率比標準狀態高,發生音升;吸音時,同風速下,其頻率比標準狀態低,發生音降,具應用性。我們發現在頻率改變時,簧片的振動型態會有所不同,所以利用高畫素像機拍攝和電腦相位差算出簧片之曲折點至尾端的距離,發現頻率和簧片之曲折點至尾端的距離成正向關係。如實驗五中頻率從414 至419Hz,簧片的曲折點到振動端距離也明顯變大。我們發現吹嘴和口琴只要稍有一點空隙(大約在0.2cm 左右),便會和完全吻合時有顯著的頻率差距(吻合後大約比有空隙低20Hz 左右),此實驗頻率變化現象和現實壓音頻率變化極為相近。實驗過程中發現,改變簧片吹嘴的吻合程度,吹入口琴的風速相近,但頻率變化卻也有壓音的音頻變化。在實驗三加入各種氣流因子發現入射角度和標準情形差異不明顯,因此推論壓音的頻率變化和風力強度、入射角度關係不大,壓音主要為渦流所造成的現象。簧片振動模式改變,導致簧片振動頻率發生變化,且簧片的自然頻率不變。當壓音產生時,氣流在振動面造成妨礙簧片振動的抗力,但琴格內部同時也給簧片的風壓,使簧片產生一種非自然振動的頻率。The theme of the research is to explore the changes on its timbre and frequency after the harmonica reed is influenced by each kind of air current factor .In the past ,most people think no matter how to play the reed ,the frequency it produced was supposed to be the same. But in fact the frequency will be changeable under different direction, turbulent flow and air intension by the perform. First to explore the basic feature of harmonica reed, for example: The length, the width, thickness cause the influence on the frequency. To make the self-made harmonica, using the transformer control air feeder wind speed. To discussion the influenced caused by air current factors,and use each kind of different self-restraint to boast, change the wind speed, angle, turbulent flow ,in order to discover possible factors the reed causes to change the frequency of the air current factor. The experimental result discovered the change of wind speed can affect the change of basic frequency , the stronger speed cause the bigger frequency, It will be a curve. But it will not be rising continuously, when the reed frequency rise to some limit, it is unable to cause the frequency rise again by using the wind speed. For example experiment four sound absorption standard conditions, after the wind speed is higher than 8 Kt, the frequency continuously stops in 429Hz. To compare obstacle (simulation plays when tongue sticks out) and the standard condition (normal zero degree incidence) , comparison blows the sound agreement sound absorption to have the obvious difference. When blows the sound, under the same wind speed, its frequency is higher than the standard condition, has the sound to rise; When sound absorption, under the same wind speed, its frequency is lower than the standard condition, has the sound to fall. The harmonica terminology for presses the sound, extremely has the application. We discovered when frequency change, the reed vibration condition have differently, therefore use the camera photography and the computer phase different figures out the reed winding point to the end distance, discovered the frequency and the reed winding point relate to end distance is being connected. If tests five medium frequencies from 414 to 419Hz, the reed winding point is away from to the vibration end also obviously changes . The different reed vibration condition cause the frequency to change. Natural frequency is constant. When cause “bending” (the frequency is lower than the standard condition), the airflow make a force keep from reed vibration. But the chamber air pressure still drive reed. therefore cause the reed to give off not natural frequency sound

Ring-shaped Round Wing

The purpose of our experiment is to analysis a specific ring shaped airplane called 'Round Wing' to know its characteristic. We've done several experiments to find its characteristics.\r First, Unlike other airplanes, Round Wing needs little time to recover its stability by comparing duration of flight.\r Second, as the eccentricity of the ring increase from 0.5 to 0.95, the stability and duration of flight are increased too. Also the size of body increase 1, 2, 3 times, the duration of flight is increased to 184%, 204%, 222%.\r Third, when Round Wings are attached each other by 2, 3, 4 they flew with high stability than before and stayed in the air much longer.\r Conclusion, Round Wing has unique characteristic (like high stability, and long duration of flight). And if additional power plant added, it can stay in the air very long. Also it can be used for leisure, patrol, broadcasting, and geological purposes.

化學中的數學與程式設計

When we were learning about organic compounds at school ,there was a unit discussing the isomers of alkane .Our teacher made us practice drawing all the structural formula of the isomers from hexane to nonane .We were much interested in the subject .However ,we often missed or duplicated some isomers .Thus , we began to think if it is possible to find a way by developing programs to let the computer calculate the exact number of the isomers of alkane . After discussion ,we set up a complete coding system .We numbered the isomers in the way that computers could decode and then wrote them in C language. Through computer execution ,the numbers of the isomers from C1 to C20 all match those on the reference website. According to the same concept , we also find a way to calculate the number of alkane with one substituted group . In the future,our goal will be focused on the research of multi- substituted alkane and cyclokane. In addition , the ionic crystal accumulation model are so variable. Take the double face-centered accumulation of NaCl for example, when the ion pairs are extended to the infinity , the potential energy of attractive field will approach a constant which is named as the Madelung Constant. We also managed to write a computer program with C language to approach this convergence with three models, including cube , octahedron , and sphere . The result turned out to be that the data of the sphere was less stable . In the other two models , when “n” is up to 43 layers , the data is identical with that on the reference website to the eight decimal point . 在學校裡學習有機化合物有關烷類異構物這個單元,老師讓我們練習畫出己烷~壬烷的所有異構物結構式,這引起我們極大的興趣!但常一不小心就漏掉或多出幾個,我們開始思考:能不能找到一個方法並設計成程式,讓電腦執行以找出烷類異構物?經過討論,我們建立了一套完整的編碼系統,將各異構物以電腦可解讀的方式編號,並以C 語言寫成程式。透過電腦執行,各碳數化合物自C1至C20都與參考網站吻合。依相同觀念,我們也設計出烷類含一個取代基的異構物數目。將來努力的目標為:多取代基及環烷類之研究!另外,離子晶體堆積模型變化多端,以NaCl 雙面心堆積為例,其引力場位能,當離子對延伸至無限大時,這個值將趨近於一個常數,又稱為馬德隆常數。我們嘗試以C 語言設計電腦程式,用三種模型(正立方體、正八面體、圓球)來逼近並求得這個收斂值。執行結果是:圓球數據較不穩定;而另二種模型到n=43 層以上,其數值大小與參考網路上的數值,在小數點以下8 位完全相同。

磁流體的浪潮-磁場梯度下磁流波紋之研究

在本次實驗中,我們發現在不同厚度的磁流體薄膜中,會因本身磁性粒子結合,而呈現不同的影像圖形。隨著薄膜厚度增加,其磁性粒子會由鏈狀排列成塊狀叢集,可是一旦外加磁場後,又要全部轉向磁力線方向集結。另一個發現是將磁流體薄膜放在一個不均勻的磁場梯度中,則樣品內的磁流體粒子,不僅會隨著磁力線的方向排列移動,更會出現磁流波紋,其行進路徑是沿著垂直於磁力線的方向,向磁力線密集處移動。我們亦發現在不同的薄膜厚度及不同外加磁場下,其”磁流波紋”的波速亦會隨之改變。一般而言,樣品的厚度愈厚,或外加磁場愈大,其”磁流波紋”的波速愈快,反之則愈慢。最後,我們列出了一些磁流波紋的應用,相信是精采可期!In this experiment, we find that in different thickness of magnetic fluid different images will appear, because of the connection of magnetic particles. With the increasing of thickness the magnetic particles will change its shape from chains to blocks. But when we add external magnetic field, they will get in line one by one to the direction of magnetic line of force. We also find that we put the magnetic fluid film in the uneven magnetic gradient, the magnetic particle in the sample not only follow the direction of magnetic line of force but also show the “magnetic wave”. Its move path is perpendicular to the direction of magnetic line of force. In the different film thickness of magnetic field, the wave velocity of the “magnetic wave” will change. In generally, the thicker the sample is, or the larger the magnetic field is, the faster the wave velocity of magnetic wave is and adverse is true. At last, we list the applications of “magnetic wave”, we believe they are marvelous!

圓來如此─西姆松「圓」的研究

若從一個三角形的外接圓上取一點,作其對三角形三邊的垂足,我們知道這三點共線,是為西姆松線。\r 那麼當此點不在圓周上的情形呢?自平面上一點對一三角形的三邊分別做垂線,得到三垂足,並作此三垂足的外接圓,我定義其為:此點對此三角形的西姆松圓。這篇作品主要成果便是對西姆松圓的研究。透過不斷的研究,發現了許多關於西姆松圓的神奇性質,並得到了一些結果,主要的研究方向:討論共點、共圓、相似。\r 這篇報告是循序漸進的,後面的結果常用到前面的知識為基礎。此篇另一特點是:全篇的證明皆是自已給出的,採用方法皆為一般幾何證明,而沒有用到解析證明。\r 在研究過程中也得到關於著名的費爾巴哈定理及大上茂喬定理的另一種證明。