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與傳統的鏡頭比較起來,廣角鏡頭可取得較大範圍的影像,所以廣泛地運用在很多地方,例如倒車攝影機、內視鏡、防盜警眼等,但是其影像會有很大的變形失真,容易造成人類眼睛的錯覺與誤判。本篇研究以倒車攝影機為例,使用了多項式函數來校正其影像的變形與失真,從程式實作的校正結果看來,我們的方法之效果還不錯,相信同樣的模式可用來校正其他使用廣角鏡頭的儀器設備之變形影像。 Compared with the traditional lens, wide-angle lens can make images of larger range, so they are widely used in a lot of places, such as move backward cine-cameras, laparoscopes, and burglarproof eyes. The drawback is that the images distort a lot and may cause the illusion to human eyes and lead to erroneous judgments. This reserch takes the backward cine-camera as example and utilizes multinomial function to correct the deformation and distortion of the image. The results show that the method we use are quite effective and the model can be applied to other equipment with wide-angle lens.
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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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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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Rubik's Cube Solver
Aim: Over the years I became quite quick at solving the cube. I was keen to see if I could create a mechanical system that would do it in a similar time. Because of financial limitations and equipment I thought it impossible to achieve my usual times of around 1 minute and so settled on a target of 10 minutes. So my aim became; “To create a mechanical system that could solve the cube 100% reliably in less than 10 minutes” What I did: I started from the view that I wanted to get it to find a solution using the process that I usually use. The downside of this approach was that this approach meant that most internet research was irrelevant to my project. Also some methods I found were very sophisticated and expensive eg. the university professor who created a system to solve it in 6 seconds. I wrote software capable of solving the cube, printed out its results then testing the instruction steps by manually manipulating the cube. This was improved until 100% reliable. I then developed the user interface to input the colours on each face. The building of the hardware to manipulate the cube proved my most difficult challenge. To get the cube flipped and rotated accurately using the 5 servos. I modeled this using lego and popsicle sticks until the movements met the accuracy and reliability outcomes I needed. Surprisingly these materials held up to the challenge. Integrating the software and hardware functional models took a lot longer than anticipated to get the software instructions executed and coordinated. A great deal of fine tuning was required. Outcome: The system solves the cube 100% of the time. I was exceptionally pleased with this result in view of the lego and popsicle stick model. On reflection I have achieved a successful working model that university students have aspired to and this gives me great satisfaction. Conclusion: While the outcome is pleasing I envisaged achieving a much faster system with easier data input using camera and colour recognition software. Unfortunately time and my budget restrictions prevented this from being developed. However this is a step I am interested in implementing in the future. The speed could be improved by designing more efficient cube solving algorithms, implementing a camera with colour recognition, and possibly rethinking and redesigning my mechanical design. I would also like to Figure 1 illustrates how the air would flow through a fan, and get pushed underground in several short HDPE pipes. This tempered air would then be fed into a small, insulated air chamber built against the home that contains an air-sourced heat pump. The walls of this chamber would have small vents to balance air pressure, and an exit near the top for cooled exhaust air. When the temperature outdoors is in the coldest stage of winter (daily average of -3.0ºC), the tempered air being brought into the chamber would simulate an outdoor ambient temperature of about 10.0ºC, allowing a heat pump to operate with a COP of ~3.79 (based on data from Goodman Air Conditioning and Heating).² This means that for every unit of energy put into the heat pump, 3.79 units of energy are extracted. 4. Conclusions: In building an enclosed air chamber for around an air-sourced heat pump, it was found that it is possible to simulate a 10.0ºC climate in the coldest parts of winter through air tempering. This will allow the heat pump to run substantially more efficiently throughout the year. This system could be used effectively to heat a home in the winter, as well as cool a home in the summer.
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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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攔截聲音─聲速測量、短距離隔音、長距離收音實驗
我們在九十一年十一月開始準備做科學實驗,利用 學校的筆記型電腦和麥克風開始做聲音錄音測試實驗,使用的軟體是在家庭錄音室網站(網址:http://club.ntu.edu.tw/~NTUMCS/studio.htm)下載的 Gold Wave 軟體,發覺這是一個可以試試看的聲音實驗。於是我們在 九十一年十一月測試,十二月初開始做實驗,並於九十二年四月底完成實驗,整個實驗歷時約半年,做實驗時間是利用禮拜六的早上。利用九十一年五月,這一個月整理數據,寫研究報告。第一個實驗是利用一支高感度麥克風(離原點 90~40 為公尺),和一支小麥克風(置於原點)來接收同一槍聲,我們利用兩支麥克風的距離除於電腦錄音程式上兩支麥克風槍聲的時間間隔,即為聲速。接下來,我們做短距離聲音的隔音實驗,將警報器置於紙箱同一位置並固定,紙箱包覆不同的材質,改變包覆材質的層數,並改變紙箱距小麥克風距離(小麥克風處為原點,接上電腦),比較隔音效果,並探討不同箱子大小,是否影響聲音振幅。第三個實驗是利用較長距離的收音(約 40 公尺),利用一把雨傘,將大麥克風綁在雨傘的中央收音,改變雨傘張開角度,看是否影響聲音振幅大小,另外我們也做了一個類似雨傘模型,貼上珍珠板,測試是否影響聲音振幅大小。
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雷射光碟(以下簡稱CD)除了在電腦、音響方面有甚佳的視聽功能外,在光線照射下,呈現彩虹狀的光譜,必定引起你我研究其光學性質的興趣。國內以CD研究光的繞射的著作,有李偉等四人近三年發表五篇,國外科教期刊自1991年迄今共有19 篇,在老師指導下,利用CD進行了8 項實驗,分成三大項。1.利用氦氖雷射分別照射舊唱片、CD、DVD,反射光形成繞射現象,由dsinθ=mλ,量出槽距。2.將CD-R 的鋁層刮掉,(整疊購買的CD-R上下有數片未鍍鋁的瑕疵片),成為透光式CD(透射式光柵),將其中心半徑5.5 公分部份,用黑紙遮住,正對陽光,螺旋狀的溝槽將陽光聚成一點,量出各色光到CD的距離,可算出色光的波長。3.透射式CD置於投影機鏡頭前方,投影機置物台上,放置化學藥品,可直接在屏上觀察吸收光譜。The rainbow of colors reflected from the surface of an audio compact disc (CD) is a familiar sight.It is the phenomenon of light diffraction. A standard CD has 20,625 turns of the spiral, and each line is spaced by 1.6μm. This provides a grating of 625 lines/mm. We used ordinary CDs as reflection grating in our experiment,and transparent factory rejects with no coating but printed data spirals as diffraction grating. We conducted eight experiments of diffraction using the two kinds of CD. (a) Determined the grating spacing of an ordinary CD using a laser beam. (b) Determined the grating spacing of a transparent CD using a laser beam. (c) Studied the diffraction patterns caused by a laser beam held at angles to a transparent CD. (d) Measured the wavelengths of sunlight using a transparent CD. (e) Measured the wavelengths of sunlight using an ordinary CD. (f) Formed a rainbow using a transparent CD. (g) Observed the scattering of light using a transparent CD. (h) Demonstrated the absorption spectrum using a transparent CD and an overhead projector.
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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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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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此篇報告中,主要是在敘述以單晶片8051為主體,運用其所具有之功能,製作成此作品,稱為記數抽籤機,又稱抽籤機,根據本篇報告結果,可歸納出以下結果:1.本實驗能讓初學者對單晶片8051之特性與功能有更深的了解,以增進實驗與成品實作的能力。2.此作品以便利為原則,故其體積不大,重量輕攜帶方便。3.使用之元件普遍,價格便宜,在電子材料行均可買的到,成本低。4.依本品之功能,可用於學校讓老師進行抽問,也可用於其他有抽籤或抽獎活動之場合,公平又公正。;In the report, we take the single chip 8051 as a main body, making use of function to do the counting drawing lots machine, which are also called drawing lots machine. According to the resultof this report, conclusions are as followings: 1. With the experiment, the beginners egt deeper understanding about the characteristics and the finished products. 2. This machine is light and its volume is small, so it is easy and convenient to carry with. 3. The essential elements are common,cheap and can easily be bought in the store which is sellong electronic materials. 4. The drawing lots machine can be used at schools when teachers want to pick out some students to ask or it can be used for some drawing lots occasion as well. The outcome is just and fair.
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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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