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本研究的目的在觀察液滴的蒸發過程,探討影響一滴蒸發方式改變的變因。我們利用數位攝影機外加近攝鏡頭,由側面逆光拍攝液滴蒸發過程,並轉錄成電子檔利用電腦協助分析。液滴影像分隔放大投影在方格紙上,以便測量接觸角及高度的變化。結果發現蒸發情形可分為三種:Ⅰ.當接觸角大於九十度時,液滴和界面的接觸線迅速外擴,直到接觸角遞減至90度後定住不動,蒸發終了時,接觸線迅速內縮,留下縮小的實心殘跡。Ⅱ. 當接觸角小於九十度時,接觸線先些微外擴迅速外擴,之後定住不動,直到蒸發終點,液體內縮,留下環狀殘跡。Ⅲ.當接觸角小等於九十度時,接觸線始終定住不變,液滴蒸發後留下原大小的實心班跡。液滴蒸發時接觸角和高度並不是連續變化,而是交互階梯式遞減。本研究的結果可應用在探討噴漆及噴墨印表機的噴墨印刷上。The objective of this investigation is to observe the evaporation of liquid drop and find out the factors that could affect it. A digital camera with micro lens is used to film the process of the evaporation. And a close-up of the sample drop is taken with backlight. The results are analyzed with a personal computer. The magnified images of the drops are projected on grid papers for measuring the changes on contact angles, and heights of drops. We classify the evaporation of a drop into three types: Ⅰ. The contact angle is greater than 90 degrees. At first, the contact line will spread outwardly till the contact angle decrease to the 90 degrees and then be pinned until the evaporation reach its terminal. At last the contact line quickly contract inwardly, and a solid stain remain. Ⅱ. The contact angle is less than 90 degrees. The contact line will spread slightly and then be pinned. At the terminal the liquid contract inward, and a ring-like stain is formed. Ⅲ. The contact angle is equal to 90 degrees. The contact line will always be pinned, and no ring, but spot stain is left. During the evaporation, we discover that the contact angle and the height of the drop do not change continuously but alternatively decrease by steps. The results of our investigation can be applied to the aspects of paint-spraying and jet printers.
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在練習作電腦動畫的過程中,做出以電腦模擬自由落體及雙星運動,但以上都屬可簡單分析出結果的運動,因此想到以電腦模型預知無法簡單分析的問題。在牛頓雜誌第 1 69 期,有一篇文章曾提到拉格朗日點:假設宇宙中有三個星體,星體 A (太陽)質量甚大於星體 B (本星),而 B 質量遠大於星體 C 。當 C 位於五個稱為拉格朗日點的位置上時(如圖),會與 B 的角速度一致,環繞 A 公轉。圖中L1L2L3三點處於極不安定的平衡位置,而位在L4L5的小行星群即使因撞擊而略為離開拉格朗日點,由於 A , B 引力的微妙作用,仍會回到穩定的點上。我們就是對這情形感到興趣。 \r
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本次試驗在設計一個氣壓式的夾娃娃機,首先運用課堂上所學習的氣壓實習與機電整合實習來規劃氣壓與電控部分部分,再利用機械原理與電腦輔助製圖來進行機械部分的設計,先把氣壓缸、氣壓夾爪與鋁擠型等元件3D 電腦化,利用3D 電腦影像來進行設計,可以讓我們更容易的掌控機具的比例,對初次設計機構的我們有很大的幫助。設計完成之後,我們也希望可以控制娃娃機的夾持的成功率,所以,設計了兩種方式來作為控制策略,首先以節流閥來控制氣壓的通過速度,結果發現,節流閥只能控制氣壓缸的出缸速度,並不能控制最後的夾持力量;第二種控制策略,利用PLC(可程式控制器)的程式來控制,結果發現,我們確實可以利用程式來控制,氣壓夾爪的點放時間和點放的次數,成功率都能夠依照我們的規劃來進行,是個又簡單又穩定的控制方式。
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強電場下DNA穿透細胞膜的蒙地卡羅電腦模擬
去年暑假,我們從Newton雜誌得知,布洛貝爾博士(Dr. Gunter Blobel)由於發現了蛋白質如何在細胞之間運送,增進了人們對遺傳性疾病的了解,因而榮獲1999年的諾貝爾醫學獎。同為高分子鏈的DNA,在基因遺傳工程中常被用來在強電場的情況下穿破細胞膜,以進行基因的改造,其穿的物理機制又為何?在一場演講中,我們知道鍵振盪模型(bond-fluctuation model)可用來模擬高分子系統,因此我們想以之模擬DNA在強電場下穿透細胞膜的行為。
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In the previous year study, we assumed that the fish basin as a column-shape model in order to exam and explain how the water spouting. This year, we established a reality-like situation of the fish basin to construct our theory base. At this point, round-waves and up-down waves are found as the beginning point of the water spouting. The sound from the basin is the frequency of the vibrations. Meanwhile, this process enables us to understand the causes of four, six, and eight waves. In addition, we tried to change the basin's positions, the capacities of water, the densities of liquids, and the sizes of the containers to demonstrate the theory. Furthermore, we used similar containers, such as high-heel cup and big magnetic bowl to experiment. The results are also corresponded with the theory. These results can also be used to explain the Chinese aeolian bell, clock, shaking bell, etc. That is a major innovation for us. Finally, we obtain better understanding of the abstractive theory though the simulation of the computerized photographs. 魚洗,也稱龍洗,傳說是中國唐宋時代皇帝洗臉的臉盆,內底四條魚紋,麟尾畢具。洗內盛水後,用手摩擦其兩個雙耳,立即發出響亮的嗡鳴聲,並出現美麗了漣漪,水珠四濺,摩擦越快,聲音越響,波浪翻騰,水珠越烈。對此在上一年度的研究中,是將洗盆視為圓柱狀,然後由圓柱狀所建立的模型去解釋水跳的原因,初步瞭解了水跳的原因。今年我們以洗盆真實的情況建立理論模型,在殼體產生共振的圓形駐波及上下駐波,此為水跳產生點,此時殼體發出的聲音就是共振的頻率。也瞭解了有四個、六個、八個、十個波腹的原因。並以改變殼體不同位置、水量、液體密度及洗盆大小等變因應證模型,結果與理論相符合。繼而以高腳杯、大磁碗等類似魚洗盆構造的容器,加以實驗應證,也能符合此理論。甚可推到中國古時候的編鐘、搖鈴、風鈴等器材。對於我們總認為碰撞就產生聲音的觀念實是一大突破。最後經由電腦動畫的模擬,讓此抽象的理論更容易瞭解。
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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。
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在網路上看到甩毛巾、皮鞭的影片,會產生巨大的聲響,查找了資料,我們知道當發聲體超過音速時便會產生音爆。部分文獻提到,毛巾或皮鞭生成音爆原因是來自於角動量守衡理論,我們想利用實驗方法來驗證其正確性,因此利用video point 來分析影片討論手的加速度和毛巾末端質量、長度的關係,並用crocodile physics 做電腦模擬,我們發現毛巾長度與音爆產生無關,這樣和角動量理論模型有所不同。所以我們嘗試利用能量守恆及自由端反射駐波理論來解釋毛巾產生音爆關係,並利用影片分析及crocodile physics 驗證其正確性。We saw the film clippings on the Internet about snapping towels and whips, which made a big noise. After going through related literature, we found out that it is called the sonic boom .Some papers say that the sonic boom results from the Location momentum conservation theory. To prove its accuracy, we used a kind of computer software called Video Point to analyze in the clippings the movement of the hand, understanding the relationship between the mass of the towel end and the length of the towel. We also used another software called Crocodile Physics to simulate the whole process. We discovered that there is no connection between the length of the towel and the sonic boom. It does not conform to the Location momentum conservation theory. We then in turn employed energy conservation theory and the trait of the standing wave (specific wave length) to explain, when we also used Video Point and Crocodile Physics to prove.
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以3DVR虛擬實境融入教學活動設計之研究
面對一個終身學習,多元化學習的社會,學習的方法不再侷限於閱讀或求教於師了,取而代之的是電腦科技的變革。上屆學長利用線上代理人融入遠距教學的作品令我印象深刻,但總覺得少了些趣味及互動性,於是本實驗嚐試將虛擬實境加入線上代理人及遠距教學,利用空間魔法師建構出來的環境,讓使可者能夠融入其中,悠遊在虛擬的世界,並配合鍵盤的滑鼠的控制移動,點選建構出來的虛擬物件,透過超連結連結至網路上的知識網頁,配合線上代理人的互動及帶領,結合了主動、趣味、互動與便利,開創未來的學習方法,一個講求效率、速度及克服空間無時無刻都能學習的環境。With the arriving of 21st century,things are widely different,including the ways of learning. Because of the revolution of multi-media,computer technology will change the traditional way of learning. I was impressed by the master piece 「Long-distance with Agent」 which was done by the schoolmates last semester. But I feel their work still have much room for improvement,so I combine to use the virtual environment with the advantages of their work. Learners can move and click the objects in the virtual reality space,and they can be linked to the knowledge website through the Internet. Learners can enjoy the interesting ,fast,interactive and efficient learning environment. This work is done by the Space Magician Ver3.0, which is used to design a 3D virtual reality environment. And the users can enjoy the net-surfing and through the hyperlinks to get the information.
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本研究希望在數位顯示方面做些改進,利用電腦運算使戶外大型LED看板所使用之能源降到最低,以達到節能減碳。\r 本研究分為兩個部份:\r 第ㄧ部份:以瑞利準則探討亮點間距與觀賞距離之關係。\r 實驗中,以Photoshop繪圖模仿LED燈泡之排列,分析兩亮點之大小、距離與觀測距離的關係來設定點之尺寸,再進一步分析三原色點之觀測距離、比例及三原色點之佈點方式對混色效果之關係,並以瑞利準則判斷之。\r 得到公式如下:\r 自己所繪之點大小/點恰可分辨之最近距離=LED燈之間隔/點恰可分辨之最近距離=0.8mm/1m \r 第二部份:數位顯示—LED。\r 利用第一部份所得知的公式發現:在某ㄧ觀賞距離時,有最佳的影像品質且有最少的用電量。較近時,則影像品質降低;而較遠時,影像品質已無法提昇,而多餘的用電量則可經由實驗省去。藉由本次實驗結果,可利用所編寫之程式計算出在某ㄧ距離下最適合之燈泡尺寸及所省之電量,以達到節能減碳的效果。
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以數位像素分析法探討兩棲類變色行為之研究
本研究是以數位科技改良生物實驗上的傳統比色法,並探討中國樹蟾及台北樹蛙的變色行為。有些兩棲類有變色行為,這是眾所皆知的現象,過去一向採用比色法判斷生物體的體色變化;然而,以人眼去測定色差,會有相當大的主觀誤差。本研究及是探討以數位科技量化並比較實驗對象的變色情形。在研究過程中,用電腦量化數位相機所拍攝的影像,以像素的方式呈現出來,得以取的準確且客觀的實驗數據,並加以解析,也經由此一實驗方式,交叉比較中國樹蟾及台北樹蛙在不同環境和不同時間下的變色情形。結果顯示:樹蛙變色和環境顏色及時間有密切關係,且在短時間內以數位量化的方式解析其變色行為的方法極為可行。The purpose of this study is to investigate the color variation behavior of tree frogs using an image processing technology. It is known that some of the amphibians have the ability to change their skin color under different circumstances. In the past, a conventional “color comparison” method was frequently used whenever it comes to analyzing the color variation of organisms. However, it is realized that evaluation of color difference by human eyes is extremely unreliable. An advanced image processing technology is thus suggested to quantify the variation of skin color of tree frogs under different conditions in this experiment. Accurate quantification can be determined from the pixel number of exhibited digital images during the experiment. The color variation of different species of frogs (Hyla chinensis & Rhacophorus taipeianus) is also compared under different parameters. It is found that the color variation of tree frogs is closely related to the color of back ground as well as time. The proposed digital quantification technique has been successfully demonstrated to be an effective method for analyzing the color variation of frogs within a very short time.
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本次研究利用Web Sevrice軟體系統和Microsoft SQL Server的全文搜尋(Full-Text search)並藉由使用者選擇的圖片組合排列從系統資料庫中檢索比對,篩檢出正確或者最相似的餐點。Web Service 是建立於網際網路上之系統架構,且為一個具開放性、分散式的軟體元件,其基礎建立在HTTP、XML、SOAP、WSDL和UDDI等標準協定上,此研究即是透過Web Service系統與資料庫伺服器的連結進行。很多數位化資訊是以沒有結構化的文字資料,存成純文字檔及格式化的文件。這一類的文字資料儲存在檔案系統,而許多組織現在將這一類資料儲存到關聯式資料庫。這樣做就可以廣泛利用資料庫的好處-包括高效能存取、查詢能力、對使用者而言簡單的應用程式使用者介面,以及安全的遠端存取、查詢能力、對使用者而言簡單的應用程式使用者介面,以及安全的遠端存取。運用此功能即可在配對完成時搜尋最佳的結果並加以排名。「打破語言隔閡-以圖點餐之數位餐廳 」不只消除語言隔閡,更讓點餐手續方便許多,並讓錯誤的可能性降低。另外圖片資料庫的增減簡單快速、介面明瞭易懂。希望這些應用及創新能讓人們用餐方便及餐廳事業蓬勃發展。This research uses Web Service software system and Microsoft SQL Server. To choose the correct or the most similar meals by checking the combination and arrangement of the pictures chosen by users form the system data banks. Web-Service is a system structure establishes at the Internet. And its an open, dispersed software part. Its foundation is established at the standard agreement of HTTP,XML,SOAP,WSDL, and UDDI. The research proceeds by linking Web Service system and data-bank server lots of digital data are stored as words files and stylization documents without any structural words data. This kid of ward data are stored at file system, and many organized systems now store them at connected data banks. By doing this, people can make the most advantage of data banks- including efficient access, inquiry abilities, simple applies user’ interface, and safe remote access. People can find the best results and place them when this function finishes matching. It can not only eliminate language barriers but also make order procedure more convenient. It can also lower the mistake possibilities. In addition, we can increase or decrease pictures of data banks easily and fast. We can make the interface understood easily. We hope the applications and innovations can make it more convenient for people to order meals. And the business of restaurant can be developed successfully.
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The human eyes can adjust automatically the color of object under different illuminants. But digital camera does not have such mechanism, must join the white balance to simulate the color constancy of human eyes. There are many existing white balance methods. They can be categorized into two types. The first type utilizes the widespread assumption on the dealing natural scenery, which has the advantage of simplicity. Another type explores knowledge of the semantic content, which has the advantage of accuracy. In this study we modify and enhance the widespread assumption methods that can adopt the advantage of the simplicity and accuracy. Our proposed method is structured in two main parts: a color cast detector and a color cast remover. The detector first analyzes the color distribution of the image with simple statistical tools to determine whether or not the image has color cast. The remover, a modified and enhanced version of the widespread assumption methods ( gray world and max RGB ), is then applied on the color cast image. From the experiment results, it demonstrates the efficacy and performance of the proposed method.人類的視覺能夠自動修正因光線變化而改變的物體顏色,但是數位取像設備的感光元件卻不具有這樣的功能,必須加入白平衡的功能,才可模擬人眼維持色彩恆常的特性。現有的白平衡演算法可分為兩大類型,第一類型為廣泛假設型,具有運算速度快、與取像設備無關的特性,但是平均誤差會較大;另一類型為預知特性型,其特徵為準確性較高,但是運算較速度較慢、建立色彩特性資訊時所需的成本較高,本篇研究針對廣泛假設型的演算法做些修正與增強,使其具有較小的平均誤差以獲得較佳色彩品質的影像。我們將影像的色偏校正分為色偏偵測與色偏移除等兩個階段來進行,由於僅有被偵測出有色偏的影像才需要進行色偏的移除,所以可以避開將無色偏或固有色偏的影像做錯誤的修正,由實驗的結果看來,我們的方法確實有效,除了具有運算速度快、與取像設備無關的優點外,其色偏校正能力也較現有的方法好,使得影像色彩更能與人眼所見相近。
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