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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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Molecular and Cellular Responses under Hypoxic Stress among Rice Cultivars with Different Flooding T
全球暖化造成水災頻繁,嚴重威脅植物生存。看似耐淹水的水稻,在完全淹水下亦有其生存危機。水稻FR13A 因耐水性極佳而常用於分子育種,IR64 產量高卻不耐水。是那些特質使稻種間有不同耐水機制?我們觀察其幼苗淹水24 小時後生長情形、通氣組織 (aerenchyma) 變化及應用即時反轉錄聚合?鏈反應 (real time RT-PCR),研究酒精醱酵的主要蛋白質:乙醇脫氫? (alcohol dehydrogenase, ADH1, 2) 及丙酮酸脫羧? (pyruvate decarboxylase, PDC2) 基因之表現量。兩種水稻的胚鞘及根都因淹水減緩生長,以FR13A 減緩最明顯。通氣組織在淹水期間都有增加,FR13A 中的形成近似於對照組,IR64 則明顯較差。FR13A 中ADH1 及ADH2 在淹水一小時後迅速增加60 至100 倍,IR64 僅增加10 至20 倍。PDC2 在IR64 中表現量的增加幅度較大,但最大值仍小於FR13A 之基礎表現量。由此可知,FR13A 在完全淹水時成長減緩而原有通氣組織則持續生長,且酒精醱酵中的基因有獨特誘導反應,因此耐水性較佳。藉由此研究揭開水稻細胞及分子生物學上的耐水反應策略,將可更精準地改良稻作使其對抗淹水逆境,解決未來因環境造成的糧食危機。Global warming increases the frequency of flooding, which drastically reduces the growth and survival of plants. Although rice (Oryza sativa) appears well-adapted to flooding of roots as it is often farmed in paddies, problems arise when the whole plant is submerged in water. I am interested in the structural and molecular responses that result in different submergence tolerances in rice cultivars. Indica rice FR13A is submergence-tolerant and frequently used in molecular breeding for this trait, while IR64 is a high-yield but submergence-intolerant cultivar. In this study, I monitored the growth rate, aerenchyma formation, and gene expressions of the carbohydrate metabolism in FR13A and IR64 seedlings subjected to submergence for 24 hours, by means of real time RT-PCR and microarray. FR13A had prominently inhibited coleoptile growth and sustained levels of aerenchyma formation whereas IR64 did not. The mRNA levels of alcohol dehydrogenase 1 (ADH1) in FR13A was induced prominently, while ADH2 was induced in IR64 during early hours of submergence. The induction of pyruvate decarboxylase 2 in FR13A was stronger than IR64. The expression of sucrose synthase was similar in both strains. Expressions of the genes involved in anaerobic carbohydrate metabolism were also studied by analyses of microarray data. My findings demonstrate that elongation quiescence, persistent aerenchyma formation and shifts in anaerobic carbohydrate metabolism gene expressions are beneficial strategies of FR13A towards submergence. Through elucidating the molecular basis of coordinating submergence tolerance genes as this study provided, it will be possible to discover multiple traits associated; hence crop improvement for flooding tolerance could be achieved.
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本實驗改良菲左測定光速之實驗,將原本的光路以光纖取代,並將原本的光源改為紅外光。做了上述的改良以後,可將實驗的空間及時間縮小。實驗中輸入固定頻率的紅外光載送週期性的訊號經光纖傳輸後,利用示波器觀察訊號的延遲時間,以此實驗技巧可精密計算出光速。在輸入訊號為0.1~5MHz時,光在光纖的平均速率為2.09×108 (m/s)。換算真空中光速c=折射率n(1.467)×光纖中速率v(2.09×108m/s)=3.03×108 (m/s),平均百分誤差0.43%,平均誤差為0.13×108 m/s,準確度為99.57%。
若取最佳輸入頻率2~3MHz所得到之數值,光在光纖的平均速率為2.05×108 (m/s)。換算真空中光速c(3.00×108 m/s)=折射率n(1.467)×光纖中速率v(2.05×108 m/s),平均百分誤差為0.33%,平均誤差為0.01×108 m/s,準確度為99.67%。
A method using optical fiber is described for measuring the velocity of light . Measuring the velocity of light usually needs a long distance and in a brief time. These experiments use optical fiber and TOSA and ROSA
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本研究設計一新型的影像投射系統,可將影像顯示的灰度位元加倍,例如,顯示面板只需用4位元,即可顯示8位元的影像;亦能充分利用光路光源,增加光源使用率。此系統使用兩片相同灰度位元的顯示面板,此兩面板所顯示的影像經過灰度的重新處理,且各經由不同光源強度比值的光路合成後,其灰度分佈將可增為原來的平方倍。經模擬與實驗顯示,此種系統很輕易就能獲得預期目標。無論使用穿透式或反射式皆可應用於目前單片液晶面板之投影系統中;未來可望利用網板來表現灰度,應用於紅外線景物投射系統中,作為紅外線影像式尋標器靜態模擬時所需的高強度動態範圍與高解析度之影像產生器。In this study, a novel image generator utilized in a projecting system has been proposed; it can double the bits of gray-level for image display and enhance the efficiency of illumination of lamp in the optical path. With this system, a 4-bit display panel can achieve an 8-bit image display. Two display panels with same gray-level bits is adopted, images on them will be processed, and then go through different path with a proper intensity ratio. The gray level distribution of image displayed which the two images combined afterward, will be the square of that of original one. The results of simulations and experiments have approved to meet the requirements. No matter transmitting or reflective types can be applied to current projecting systems with single LCD panel. It is expected that a halftone-gray-level pattern will be suitable for this system to form an infrared scene projector, and to act as an image generator with high dynamic range and resolution for static simulation of infrared imaging seeker.
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幾丁聚醣包埋酵母菌球株對重金屬離子廢水處理
本實驗的目的,就是希望利用幾丁聚醣除污的效果,再配合酵母菌所能累積金屬的能力,以酵母菌包埋於幾丁聚醣的方法,吸附廢水中的重金屬離子.用Langmuir 理論求得飽和吸附量,進而求出休眠酵母菌-幾丁聚醣所能吸附金屬離子(銅)0.2048(g/g)的數量,與活化酵母菌-幾丁聚醣所能吸附金屬離子(銅)0.1750(g/g),並比較回收效率,以應用於處理工業上工廠所排放的廢水. In this experiment , we want to use the ablation of chitosan and the accumulation in metal of saccharomycete to absorb the metal cation of waste liquid . In the process , we embedded the saccharomycete in chitosan to absorb the metal cation , and obtained the impregnate absorption of dormant saccharomycete and activated saccharomycete by the theory of Langmuir . Then , we compared the efficiency of them and applied them to work on the waste liquid in industry.
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近幾年來,蠶繭彩色化已引起廣泛的注意,日本與中國大陸紛紛投入此研究領域。我們用食用色素、酸性染料和活體染色劑中性紅等色素水溶液,以沾附於桑葉餵食、浸泡蠶體、注射入蠶體血腔等方法,使白色繭品系的家蠶生產出多種顏色的彩色蠶繭,其中以附於桑葉餵食最有效率,我們就此法找出投與色素的有效期間,可以比日本、中國的方法更節省色素。同法處理黃色品系的家蠶則產生黃色與所加色素的混合色蠶繭。由於這樣得到的彩色蠶繭放久了都會褪色,我們試用奈米色素餵食家蠶所得彩色蠶繭,與一般食用色素所製成的彩色蠶繭比較,發現對各種光照、清潔劑清洗等處理,用奈米色素所得蠶繭明顯較用一般食用色素所得蠶繭不易褪色。這樣用奈米色素生產的彩色蠶繭,因為解決了褪色的問題而更具有潛在的產業價值。To make silkworm cocoons with different colors has received a great attention recently. Japan and China have invested great resources in this field of the study. In order to let white cocoon silkworms produce cocoons of different colors, we used the aqueous solutions of food dyes, acid dyes and neutral red, and fed the worms with mulberry leaves immersed with such aqueous solutions, or directly soaked or injected them with the solutions. We found that using mulberry leaves immersed in the dye solutions was the best approach. We improved this approach by finding a critical, effective time of applying dyes. It saved the dyes and labor than those of Japan and China. We also found that yellow cocoon silkworms produced yellow and mixing colored cocoons by the mulberry leaf feeding method with the same dyes. Because all colors of the cocoons mentioned above faded easily, we furthermore tested nano-dye and found that colors of the cocoons had better resistant to fading away in washing with detergents under various types and intensities of light illumination. This result suggested that nano-dye has a potential in solving the fading problem of the colored cocoons.
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The role of miRNAs in plant development and virus defense
微型RNA是最近發現的小RNA,調控生物體內的反應,包括生長、細胞分化、對抗病毒…等。植物利用RNA干擾 (RNAi) 或過敏反應 (HR) 對抗病毒感染。有趣的是,miR168可藉由降解mRNA或抑制轉譯,調控阿拉伯芥AGO1的表達,而AGO1是RNAi的一個重要元件。miR398則調控銅鋅超氧化物歧化? (CSD1, CSD2) 的表達,而CSD1, CSD2負責產生過氧化氫去引發細胞凋亡 (cell apoptosis)。帶有竹嵌紋病毒 (BaMV) 全長基因的轉殖菸草 (Nicotiana benthamiana) 品系27-17是我們的研究材料。27-17的幼葉不具病徵,隨著葉子的生長,病徵會漸漸變嚴重。我發現被病毒感染時,植物會提高AGO1的表達,使RNAi更有效率。然而,病毒藉提高miR168使AGO1的量無法上升。植物亦可提高CSD1, 2 mRNA的量,促進細胞凋亡。病毒卻會引發miR398降解CSD2 mRNA。在病毒力價高的葉子中,雖然CSD2 mRNA降低且miR398升高,植物仍可大量提高CSD2蛋白的量。CSD1 mRNA沒有被miR398負調控,詳細原因仍有待研究。
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本研究以均相沉澱法合成多成分的銅鋅鋁觸媒系統,並嘗試克服傳統共沉澱法的不均勻性且提高比表面積,過程中我們利用改變尿素濃度、水添加量、反應溫度與時間等四種變因成功合成出具有高活性的銅鋅鋁觸媒。研究得知最佳的合成條件為尿素3M 並添加三倍體積的水,在95°C 下反應2 小時。與傳統觸媒相比,均相反應合成的銅鋅鋁觸媒除了有較小的粒徑外,其還原溫度也較低,顯示較佳的觸媒活性。而在250°C 甲醇重組的製氫反應條件下,均相反應合成的銅鋅鋁觸媒也有較高的甲醇轉化效率、氫氣產生率以及CO2 的選擇率,而添加鈰與鋯可更進一步使觸媒活性再提升。未來除可利用此合成方法合成均勻性佳的多成份材料,亦可應用此高效能觸媒進行甲醇重組反應以產生氫氣提供燃料電池使用。; Multi-composition Cu-Zn-Al catalyst system was synthesized by homogeneous precipitation method. This method was anticipated to improve the homogeneity of metal mixing and to increase the surface area of catalyst derived by conventional co-precipitation method. In the research, we successfully synthesized Cu-Zn-Al catalyst with high activity by adjusting four experimental parameters -- urea concentration, water amount, reaction temperature and reaction time. The better catalyst can be obtained under urea concentration of 3M diluted by 3 times water, and the kinetics conditions of 95°C and 2h. Compared with the co-precipitation method, homogeneous precipitation method derived Cu-Zn-Al catalyst performed higher methanol conversion, hydrogen production rate and CO2selectivity under methanol reforming reaction at 250°C. Modifying the support by addition of Ce and Zr might further improve the activity of the catalyst. In the future, not only can this method apply on synthesizing other multi-composition materials with high homogeneity, but also the high performance catalyst can be used to do methanol reforming reaction in order to supply hydrogen on fuel cell.
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Gene Targeting Using Chimeric RNA-DNA Oligonucleotide for Capase-10 in Various Cell Types
The process of gene targeting via Chimeraplasty is achieved by using a RNA-DNA oligonucleotide homologous to a gene of interest ,to introduce a single base pair or frameshift mutation in genomic DNA .The extensive use of chimeraplasty is currently limited by wide variation in its gene conversion rates(.01-40%) and its mechanism of action remains to be fully understood. For cell studies, chimeraplasty is an alternative strategy to homeologus recombination in generating gene knockout models.
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塑膠海岸-臺灣東北海岸微小塑膠污染之研究
一、目的:1.找出基隆沿岸是否受到塑膠微小物的污染,建立塑膠成分的簡易檢定法,3.分辨所發現塑膠微小物成分,4.試圖分析其污染源,並尋求減輕汙染方法。二、結果:本研究為首篇證實東北部海岸已遭受塑膠微小物污染之本土研究。我們想出了不用昂貴儀器的位之塑膠簡易成分判別法,發現海面漂浮的油渣含有塑膠微小物,還觀察到海岸生物(藤壺)由本來附生在岸邊的石頭上轉而附著於漂浮的塑膠垃圾及漁民和釣客所使用的浮標、漁網、浮桶等。三、為減少海岸的塑膠微小物污染,建議政府立法規定業者主義塑膠原料運送中產生的問題,並提倡垃圾分類,人民本身也應自我覺醒。Taiwan is an island, and the sea is very important for us. So in this study, we tried (1) to examine the small plastics (resin pellets and plastic fragments) pollution of the northeast coast, (2) to identify the components of unknown plastics by burning, soluability in organic solvents and relative weight but without using expensive instruments, and (3) to classify the small plastics we found and to find out where were they from. Our study is the first grassroot research proving that the northeast coast of Taiwan has been polluted by small plastics. We attempt to identify the components of unknown plastics without using expensive instruments. The present study discovers that there are many small plastics in the floating oil scum. The relation between the oil scum and small plastics needs more study. We finds marine life (bamacles) growing on floating small plastics. The ecological importance of this discovery needs more study. We also make suggestions for reducing the minute plastic pollution of the coasts: (1) the government should ask big companies to be more careful on the transport of plastic pellets, (2) people should be aware of the problems caused by small plastics.
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The feasibility of new design approach for dual-band antenna array using genetic algorithm is demonstrated in this study. In the past year, one dual-band printed-strip dipole antenna, which operates at 0.9/1.8 GHz, had been implemented in the laboratory and leads to a satisfactory performance. However, the antenna element is suitable for application at base-station rather than handset. Conventional antennas suitable for base-station application are arrays, which consist of antenna elements and at least one feed network. Feed networks for antenna arrays are usually designed to operate at single-band capability, and therefore, it requires two feed networks for a conventional dual-band antenna array. Nevertheless, a dual-band antenna array fed by signal feed network is feasible in our study. To begin with, a full-wave solver ID3D is applied to evaluate the impedance matrix of antenna array with eight elements. Then, the antenna array is modeled as a cascaded equivalent transmission line such that the genetic algorithm could network of dual-band antenna array and yields a seven-section design, which meets the specification of base-station antennas.在過去的一年裡,本人曾製作過具有雙頻效果的雙面印刷偶極天線,並得到不錯的量測結果。由於此天線單元於實際應用上適於基地台天線陣列之設計,所以本研究著眼於天線陣列的設計。傳統上天線陣列的結構包含了兩個部分,分別是天線單元以及饋入電路。目前基地台所使用的大多都是單頻天線陣列,在雙頻天線陣列部分,通常需要兩個饋入電路分別對不同頻帶作訊號的饋入;因此,我們希望能實現使用單一饋入電路製成雙頻天線陣列的想法。本研究中,我們利用之前所做出來的天線單元來合成陣列,並希望此陣列在0.9HGz和1.8GHz兩個頻段都能產生良好的共振效果。我們利用電磁模擬軟體IE3D估算具有八個天線單元的天線陣列阻抗陣列後,再將此天線陣列轉換成串接式等效傳輸線電路。借由基因演算法(genetic algorithm)對此電路做最佳化,我們可以求得饋入電路各段傳輸線的尺寸。由此研究發現,我們的方法應用於單一饋入電路之雙頻天線陣列的設計是可行的,而此電路的模擬結果亦符合基地台天線陣列的規格。
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嗜甲烷菌對丙烯催化模式之比較-溶解型與微粒體型甲烷單氧化酵素
在嗜甲烷菌中,甲烷與甲醇間的轉化是由甲烷單氧化酵素來進行。目前已知有兩種型態\r 的甲烷單氧化酵素,一種是溶解型甲烷單氧化酵素,存在於較低銅離子濃度之水溶液環境中﹔\r 另外一種為微粒體甲烷單氧化酵素,鑲嵌在細胞內質膜上,表現於較高的銅離子濃度環境下。\r 除了本身的天然基質-甲烷之外,其他種類之簡單烷烯類化合物,甚至芳香族化合物,均可\r 作為此酵素催化的基質。其中,甲烷單氧化酵素將丙烯轉化成環氧丙烯與甲烷轉化成甲醇的\r 催化活性非常接近,因此丙烯普遍被用來作為酵素活性測量的基質。為了直接測量它們的活\r 性,我們設計出一種方法,可以讓我們直接利用氣相色層分析儀,來偵測細胞的催化反應過\r 程。基於異丁烷在甲烷單氧化酵素幾乎不存在任何活性,故我們將其作為內標準氣體,並藉\r 由丙烯在氣相色層分析儀中吸收訊號的遞減來偵測細胞的催化活性。在多樣性的動力學實驗\r 中,我們發現以sMMO 為催化酵素時,丙烯的轉化是依據一級動力學反應趨勢而減少。相對\r 的,以pMMO 為催化酵素時,丙烯的減少趨勢則是依據零級動力學反應模式進行。在比較完\r Pipes 緩衝液、上清液蛋白質及內質膜蛋白質溶液之丙烯吸附量測試結果後,我們發現內質膜\r 蛋白可吸附的丙烯分子相對於其它兩種溶液是最多的。依據Michaelis-Menten 動力學理論,\r 可得到以下結論﹕丙烯的轉化在sMMO 中是以基質受限的催化形式進行,而在pMMO 中則\r 已達到最佳的催化速率。\r \r In methanotrophs, the oxidation of methane to methanol is catalyzed by methane\r monooxygenase. There are two distinct forms of the enzyme associated with different gene\r products. One is the soluble methane monooxygenase (sMMO) expressed in the cytosolic portion\r of the cell and grown under copper-limiting growth conditions. The other enzyme is the\r particulate methane monooxygenase (pMMO), a membrane-associated protein that is expressed\r under high copper-to-biomass ratios. In addition to the natural substrates of methane gas,\r simple aliphatic alkanes, alkenes, or even aromatic compounds could be used as the substrates of\r the methane monooxygenase. In those gaseous simple alkenes and alkanes, propylene converted\r to propylene oxide by methane monooxygenase has been considered as popularly use for enzymatic\r activity determination because of its comparable activity to the methane gas. To measure the\r catalytic behavior of the methanotroph directly, we design a method to choose isobutane as the\r internal standard because of the negligible activity in the methane monooxygenase. The catalytic\r activity can be simply inferred from the decrease of the gaseous propylene signals in the GC\r chromatograms by generating the liquefied epoxides mediated by MMO within the methanotrophic\r bacteria. Under various kinetics measurements, when we incubate the methanotroph grown under\r copper-limiting concentrations, we observed the diminishment of propylene follow a first-order\r kinetic behavior with the over-expression of soluble methane monooxygenase. However, the\r growth of bacteria under 40 M presents the zero-order kinetic trend with the bulk expression of\r pMMO. After the quantification of the dissolved propylene in the deionized water, soluble\r proteins solution as well as membrane proteins solution, we observe the membrane proteins could\r adsorb more propylene molecules in comparison with the other solution mixtures. By considering\r Michaelis-Menten kinetics, we conclude the propylene conversion in sMMO is under substrate\r limiting catalysis whereas the pMMO has attended the optimized velocity of propylene conversion.
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