以熱聲效應改善微電子裝置散熱的研究
近年來在熱聲效應方面的研究產生了許多新發明,如冰淇淋冰箱與太空梭溫控系統等。然而,將熱能轉換成聲能的熱聲引擎,在散熱方面的效用只有被提起而從未被實際應用。本研究參考美國賓州大學「聲學雷射」裝置來研究熱聲引擎的特性,並提出一個以熱聲效應改善微電子器材散熱的裝置。它的優點是由電子裝置產生的熱即可啟動熱聲效應,而熱聲效應所加強的熱對流可降低該電子零件的溫度。實驗中發現透過熱聲效應的強烈散熱,可以大為降溫,由200℃降為50℃左右,這正是當代電腦內中央處理器(CPU)的工作溫度範圍。未來的研究可以針對陣列式的熱聲散熱裝置進行測試。In this project, the characteristics of the thermoacoustic engine were first studied using the “Acoustic Laser” concept. A passive thermoacoustically enhanced convection engine capable of improving the cooling effect of microelectronic devices was then proposed. This design has the advantage that no additional energy input is required, a contrast to the usage of mini-fans in today’s computers. A testbed combining a heated NiCr wire with a glass tube was used to examine the overall cooling effect. In order to evaluate its performance, we measured the following parameters: radiation, convection, conduction, and acoustic radiation. We found that the heat caused by today’s microelectronic devices is sufficiently high to trigger the thermoacoustic effect. Based on this finding, we designed a new configuration to utilize this thermoacoustically enhanced convection to significantly lower the temperature. Our approach has a potential application to tackle the heat problems caused by the rapidly advancing microelectronic devices.
南爭北鬥之壁虎大戰一蝎虎與無疣蝎虎種間競爭程度之評估
無疣蝎虎(Hemidactylus bowringii)與蝎虎(Hemidactylus freuatus)分類上屬蜥蜴目守宮科蝎虎屬,為本島住家附近常見且生態地位相近的壁虎,近年來因人為因素使原本有地理區隔的兩種壁虎在北部地區產生共域現象。本研究利用問卷來調查兩種壁虎分佈狀況,並用「體型大小」、「食物競爭能力」兩種指標,設計實驗評估種間競爭程度,來探討兩種居家壁虎種間競爭程度。問卷調查及物種採集結果顯示,在台北市各行政區確實存在共域現象,且分佈數量互有消長。體型大小比較上,蝎虎體型較無疣蝎虎稍大,但在統計上無顯著差異。食物競爭能力強弱比較上,以斷尾後尾巴增長量為指標,結果兩者大致相等,無顯著差異。綜合以上研究結果,顯示兩者共域後會出現種間競爭現象,程度大致相等,有互相消長現象。Hemidactylus bowringii and Hemidactylus freuatus are commonly seen in Taiwan, and their habitats are very near the area people live. Recently, two species have inhabited the same or overlapped geographical areas in northern Taiwan. This sympatric phenomenon resulted from the geographical isolation being broken by people. This research investigated their distributions in Taipei city by using questionnaire, and evaluated the degree of interspecific competitions by using indexes of the body size comparison and the food competition to design our experiments.According to results of questionnaire and animal sampling, two geckos did inhabit closely in some areas in Taipei city, and their population distributions were changing with time. According to the result of the body size comparison, Hemidactylus freuatus is bigger than Hemidactylus bowringii. But there is not a statistically significant difference between two species. The degree of food competition of two species was all square. In summary, it was occurred the interspecific competition between Hemidactylus bowringii and Hemidactylus freuatus, and the degree of competitions was almost equal.
Design of a Computer Interface for a Robotic Arm Actuated by VHB 4910
Recently, there have been several researches aimed at the feasibility of electroactive polymers (EAPs) replacing motors as robotic actuators – the driving forces behind mechanical devices. However, current EAP actuators are either hard to control or incapable of discrete accurate movements. The research aims to design a computer interface that makes it possible for the electroactive polymer, VHB 4910, to become an effective substitute for bulky motors in effecting precise and accurate control of a robotic arm.
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.
敬"屑"不敏 --- 皮屑芽孢菌生長之探討
由於本身有頭皮屑的煩惱,在使用各種洗髮精之後,一方面覺得大部分的洗髮精效果不是很好,另一方面也擔心抗屑洗髮精的成分對人體有害。所以有了研究頭皮屑的念頭,希望能找出減少頭皮屑的方法。\r 在與幾位皮膚科專門醫師討論後,醫師們都不建議在直接人體上進行減少頭皮屑的實驗。於是我們將研究的重點放在〝皮屑芽孢菌生長之探討〞,希望對皮屑芽孢菌有更深入的瞭解。除了洗髮精之外,我們也將研究各種廣為流傳的民間偏方是否能有效抑制皮屑芽孢菌生長。在這些民間偏方的蒐集可兩大類:一類是在日常生活中可以很容易取得的物質,如鹽、醋、大蒜、生薑、洋蔥等;另一類則是台灣特有的物質,如無患子、茶籽粉、竹醋液等。\r 我們希望透過研究方法能瞭解\r (一) 溫度、濕度、酸鹼度、油脂對皮屑芽孢菌生長的影響\r (二) 哪些物質可以抑制皮屑芽孢菌的生長\r (三) 不同稀釋濃度的物質抑制皮屑芽孢菌的生長的效果\r 為了避免繁複的數量計算(如菌數計算),我們採用較多的對照比較(如抑制圈大小)。同時,我們設計了一個簡易的觀察與測量方法(稀釋法與抑菌指數),來比較各種民間偏方\r 的抑菌效果。\r 研究與實驗分為四大項進行:\r (一) 基本生長環境之探討:溫度、濕度、酸鹼度、油脂對皮屑芽孢菌生長的影響\r (二) 民間偏方抑制效果之探討:鹽、醋、大蒜、生薑、洋蔥是否能抑制抑制皮屑芽孢菌的生長\r (三) 民間偏方抑制效果之比較(抑制圈):比較各種物質的抑制圈大小\r (四) 民間偏方抑制效果之比較(稀釋法):利用抑菌指數來比較各種物質的抑菌能力\r 經過研究,我們所蒐集到的民間偏方都有某種程度的抑菌效果,大致可以分為強效(蒜液、竹醋液、茶樹精油)、有效(食鹽水、食用醋、洋蔥液、檜木芬多精、茶籽粉)及普通(薑汁、無患子)三種效果。\r \r Since I have the serious dandruff problem, I try to seek, except the shampoo, the natural materials to decrease the dandruff. After consulting with some dermatologists, they suggest I can focus my research on the “Malassezia Furfur”, which is the major bacteria causing the dandruff.\r This project is designed for finding the materials which have the most powerful inhibition capability for the “Malassezia Furfur”. I collect some folk prescriptions from the internet that salt, vinegar, garlic and onion can decrease the dandruff. The problem is “Do they have good inhibition capability for the Malassezia Furfur too?”\r The goals of the research are as followed.\r (1) The exploration of the basic environmental factors for the growth of Malassezia Furfur, such as temperature, humidity, acidity & alkalinity.\r (2) What kinds of material have the good inhibition capability?\r (3) The comparison of inhibition capability of the different material with different consistency.\r We especially design a method called “Dilution metering and index” to compare the inhibition capability of the different material. By using very simple observation, this method will transfer the simple “Qualitative Analysis” to the result of complicated “Quantitative Analysis”. The “Dilution metering and index” is the major achievement of this project, and it is also the good way for the projects which are not equipped with the precision instrument for bacteria inhibition capability measurement.