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本研究的目的在於探討蜻蜓兩對翅膀在不同的相位差之下對升力有什麼影響。在觀察蜻蜓及察閱相關網站、研究後發現蜻蜓前後翅的相為差有相差0.5 週期、相差0.25 週期、同週期三種不同振翅方式。在界定欲實驗的種類和評估現有的能力及資源後,決定研究加上相差為0.125 週期的四種振翅方式,於無風條件、相同的振翅頻率下進行實驗,測量其升力的變化週期。測量結果參照前人的文獻後發現,0.5週期產生的升力雖最小,但最平穩,所以為蜻蜓最常用的飛行方式。而0.25 週期升力會疊加,往下的力被抵銷,故為向上加速時使用。 ;The purpose of this study is to investigate the phase-shift between the front-pair and rear-pair wings on the maximum lift of a dragonfly. As observing the flight of a dragonfly and the literature survey from web sides, it has been observed that the general phase-shift modes of the dragonfly are in-phase-shift, 1/2 period and 1/4 period. It has been decided to include a 1/8 period phase-shift mode into the known three modes under the no wind condition with a fixed flapping frequency, the cyclic lift force of the dragonfly wing model has been measured. When it is flapping, we put the model on an electronic scale for measuring the weight of the model. After that we minus the original weight of the model, knowing the increasing or decreasing weight and the extra weight is the lift force. The results show that 1/2 period phase-shift mode produces the least lift force; however, it is the most stable flight, and is being adopted by the dragonfly for level flight. The in-phase-shift mode can produce more lift force on the flapping processes. The 1/4 period phase-shift mode produce the most acceleration, being adopted by the dragonfly for the climb flight.
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The starting point of this experiment is to study the structure of soap-film. By changing the height of the triangular prisms, cuboids and pentagonal prisms, I observed the patterns set by the soap within the frameworks. It is surprised that when the proportion of prism is in a specific range, the phase in the middle of the structure will overturn 90 degree and then transmitted into another kind of balance pattern. I named this process “phase transition”. According to the experiment ,we can conclude the change of film patterns within variable prisms are all applied to this regular cycle::
We know the soap films are forever attempting to minimize their energy. It stands to reason that surface tension tend to set up the film in its minimal surface. From the point of Mathematic, each structure should have only one single balance pattern, which is set up on the base of Fermat point and this pattern should stand to the minimize of it’s energy. However, we discovered that in some specific cases, one structure can allowed two kinds of balance films-patterns to exist. In these cases, any small vibration can cause the happening of “phase transition”. To sum up, I presume some structures have two different types of balance film-patterns: one of which stands to the local minimum (in this condition the pattern’s surface area isn’t the smallest); the other stands to the absolute minimum (in this condition the pattern’s surface area is the smallest).
There is an energy valley separate local minimum from absolute minimum. The second pattern (local minimum) will appear when the structure is blocked from attaining its absolute minimum, but surface intention is not powerful enough to support the film jumping over the energy valley. In this condition, if we works on the structure (such as blowing), which would provide the film of energy to cross the valley, and then phase transition take place. Vice versa, we can also force the film to jump from absolute minimum to local minimum and phase transition will occur as well. In a word, phase transition can happen in each two way, which connects the two types of balance pattern.
This report lays stress to find out the condition of phase transition. We also analyze the structure of soap-film by its included angles and surface area in hope to go deep into the science of soap-film.
我們實驗的出發點在於研究泡膜的立體結構。藉由改變正立方柱的高,觀察其平衡薄膜形式,意外的發現當正立方柱的邊長比在某個範圍時,泡膜結構中央會瞬間90 度翻轉,形成另一種平衡型式,我們將這個過程命名為面轉變(Phase Transition)。為了進一步了解面轉變發生的相關因素,我們設計了一連串的實驗,針對正三角柱、正四角柱、正五角柱、正六角柱發生面轉變的時機和條件分析討論。此外,我們還分析了泡膜結構中膜與膜夾角的特性、最小表面積和表面能之間的相關性,對於泡膜的立體結構做了一系列深入的探討。
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阿拉伯芥AtYAK1 基因5'UTR 中的開放讀序框(uORFs)對基因表現調控之探討
在模式植物──阿拉伯芥(Arabidopsis thaliana)中,AtYAK1(Arabidopsis thaliana Yak1-related protein kinase)是目前發現唯一屬於DYRK(Dual specificity Yak1-Related protein Kinase)的蛋白激?。雖然之前研究已證明,不同物種之DYRKs 和細胞的生長與發育過程有關。然而,其在植物中的生理功能卻尚未被明確地研究報導過。在先前的研究中,為瞭解AtYAK1 在阿拉伯芥內作用之位置,前人選取AtYAK1 基因ATG 上游約2.5 kb 的序列(Upstream Element, 2.5KUSE)建構至一含有GUS(β-glucuronidase)報告基因的質體中,並轉形至阿拉伯芥,進行GUS 組織染色分析。但在初步結果中,並沒有在轉殖株觀察到明顯的GUS 表現。進一步分析,我們發現在2.5KUSE 序列末端約0.5 kb 的5’非轉譯區(5’untranslated region, 5’UTR)中,有四組開放讀序框(Upstream Open Reading Frame, uORF)。有趣的是,許多研究也顯示,uORFs 會影響轉譯過程中的再起始(re-initiation)作用而調控該基因的表現。另一方面,前人亦透過構築好的2KUSE 轉殖株(即不含有5’UTR)進行上述GUS 實驗。結果發現,此2KUSE 轉殖株的GUS 表現非常顯著。本實驗即要瞭解AtYAK1 的uORFs 是否也會影響其蛋白質的合成。首先,我們以點突變的方式將四組uORFs 中之ATG 換成TTG,目的為構築不含有uORFs 之5’UTR(mutated uORFs, ΔuORFs)。在進行原生質體短暫表現分析法(protoplast transient assay)及GUS 組織染色分析後,將結果與含有uORFs 的結果作比較:當缺乏uORFs 後,其3’端報告基因的表現量確實比原來顯著。綜合以上,我們認為此uORFs 對於AtYAK1 蛋白質之表現佔有相當重要的影響地位。最後,我們對5’非轉譯區是否存在開放讀序框進行阿拉伯芥全基因組分析,相關結果亦於本研究報告中分析討論。AtYAK1(Arabidopsis thaliana Yak1-related protein kinase)is the first DYRK(Dual specificity Yak1-Related protein Kinase ) family member identified in the model plant ─ Arabidopsis thaliana and exists as one copy gene in Arabidopsis. Previous studies showed that many eukaryotic DYRKs are involved in regulating the growth and development of cells. However, the study of AtYAK1 in Arabidopsis is lacking to date. In order to understand where AtYAK1 expresses and functions in plants, a 2.5 kb fragment which is located upstream from the major ATG of AtYAK1(termed Upstream Element, 2.5KUSE)was previously constructed to drive the expression of a reporter gene, GUS(β-glucuronidase), in transgenic Arabidopsis. Much to our surprise, no GUS expression signal could be detected in such transgenic plants. When further analyses were performed, we found that there are four upstream open reading frames (uORFs) in the 5’untranslated region ( 5’UTR ) within the 2.5KUSE. Many studies indicating that the uORFs can regulate the translation of downstream ORF encoding the major gene product through the procedure of translation re-initiation. This action represents a mode of translational regulation for gene expression. Indeed, GUS activity could be readily detected in transgenic plants expression 2KUSE::GUS, a construct lacking the 5’UTR of AtYAK1. In this study, I have tried to elucidate whether the uORFs of AtYAK1 can regulate the translation of the downstream major ORF. First, in order to construct a 5’UTR fragment of which uORFs have been mutated(ΔuORFs), we apply site-directed mutagenesis to substitute ATG with TTG for the four uORFs and examine the expression of GUS driven by this mutated 2.5KUSE. After analyzing the results in both Arabidopsis protoplast transient assay and transgenic Arabidopsis, stronger expression of reporter genes in both systems were observed when the four uORFs were mutated. We have also confirmed that, in transient expression system, the increase of reporter gene activity was not due to the excess accumulation of the corresponding mRNAs. Rather, it is the four uORFs which play an important role in negatively regulating the translation of AtYAK1, possibly via inhibiting the translation re-initiation of major ORF. A genome-wide examination of uORFs in all Arabidopsis genes was also performed to assess the possible contribution of uORF in regulating gene expression.
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Quantitative Analysis of Organism Growth Using Fractal Dimension Statistics
Cultures of bacteria were analyzed using fractal geometry and statistics to provide a method for predicting organism growth, paving the way for a better design of treatment drugs. Images of three cultures of isolated Bacillus subtilis were taken at time intervals of two to three hours for eight days. The images were processed using the IDOLON program and quantitatively described using three statistical formulas: fractal dimension D, Renyi dimension and Hausdorff-Besicovitch dimension. The three variables were integrated to compute the maximum of the distribution and were used as coordinates for a 3-dimensional graph f. A 2-dimensional graph g containing the maximum of a distribution under time analysis was also constructed. Topological properties of the graphs, including slope, direction and area were used to determine the interrelationship of the three fractal values. The two graphs, described as φ - : X -? P1 where X is the smooth algebraic assimilation of the four variables under time analysis, was extended using Java. A computer-aided prediction model of the graphs f and g were made which combined the topology of f and g at infinity. The computed fractal values showed the existence of a fractal pattern in the growth of Bacillus subtilis with fractal dimension ranging from 0.900 to 4.000, indicating a linear iteration. This was supported by the values of the Renyi dimension, which showed a horizontal growth pattern of the bacterial cultures, establishing the growth of the bacteria to be inclined to go towards the North East direction. There was consistency in the computed fractal values, maximum of distribution and topographical computations of all three cultures which also indicated the existence of a pattern of growth which could be extended to tinfinity, thereby allowing prediction of the direction and rate of growth of the bacterial colonies. The fractal patterns in the growth of bacteria, in this case Bacillus subtilis, yielded the direction and rate of growth of the bacteria as shown by the analysis of the fractal patterns and statistical values, showing that the growth of harmful organisms can therefore be predicted, making it possible to improve on the design of drugs for the control of perilous cells. By preventing the growth of insidious cells, the potential effects of virulent organisms may be avoided, and treatment may be made more possible.
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本文由‘‘分數7/17是否能表示成兩個相異的埃及分數之和’’這個問題出發,藉由簡單數論的性質以及反證法,得到一個真分數可表示成兩個相異埃及分數之和的定理檢驗法(定理1)。有了這個基礎,我們進ㄧ步推廣定理1 的結果,做出了嶄新的結果(定理2、定理3) 。此定理分別可以用來檢驗真分數表示成三個、四個相異埃及分數之和的存在性; 至於將真分數表示為5 項、6 項….k 項相異埃及分數之和的部分尚在嘗試。利用定理1、2,我們寫了兩個Matlab 軟體工具的電腦程式,使得我們可以檢驗任意真分數是否可以表示成兩項及三項的和,並可把所有的解列出來; 最後我們研究的是一個有關埃及分數的猜想(Erdos-Strauss Conjecture)問題,當分子為4,且分母為4k、4k+2、4k+3 時,猜想皆成立。對於分母為4k+1 而言,當k 為3r+1、3r+2 猜想亦成立,k=3r 且r 為奇數時也是成立的,因此目前需解決的問題只剩分母為24t+1 的情況了。值得一提的是,我們用Matlab 的程式檢驗出當分母為1014 至1014 +240000 之內的正整數時,猜想都是成立的,這已經超越了已知文獻的結果。This paper begins with the question: ‘‘Is 7/17 able to be the sum of two different Egyptian fractions?’’ to discuss the problem of Egyptian fractions. According to the complete division properties and the counter-evidence method, we get a back-check theorem which is about a true fraction can be the sum of two different Egyptian fractions (see theorem 1). Using the same method we obtain a new back-check theorem that is a fraction can be the sum of three or four different Egyptian fractions (thereom2, thereom3). Similarly, we can follow the same procedure to get the rule that a fraction can be the sum of five or six …or even more different Egyptian fractions. By the theorem1 and 2, we propose two programs written vie the Matlab software to examine that any true fraction can be the sum of two items and three items or not. Finally we focus on the Erdos-Straus Conjecture, which related about true fractions can be divided by three different Egyptian fractions. The conjecture is when the denominator is 4k, 4k+2, or 4k+3, the problem mentioned above can be solved. As for the denominator is 4k+1, then the conjecture also can be solved, as k equals to 3r+1 or 3r+2. Also, k being 3r and r is an odd number, the conjecture is satisfied. As for the case of r equals to even number, the problem has not been solved. But it is worth to mention here that we use Matlab software to examine the conjecture is agreeable as the denominator is between 1014to 1014+ 240000. This is beyond the results from the literatures.
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黑擬蛺蝶(Junonia iphita iphita)的幼蟲生存策略
黑擬蛺蝶(Junonia iphita iphita)為台灣地區常見的蛺蝶,其幼蟲具有築巢行為,但文獻中對其幼蟲行為的描述極少,因此本實驗探討黑擬蛺蝶幼蟲在野外的族群變化與環境之關係,並研究幼蟲築巢行為,以探討其適應環境的生存策略。首先於室內及恆溫生長箱中飼養幼蟲,以建立其生活史基本資料,並於野外統計各齡期幼蟲在不同植物上的數量變化及築巢行為的差異,以探討不同環境因素對幼蟲築巢之影響。由實驗結果得知,黑擬蛺蝶生活史短,可取食多種爵床科(Acanthaceae)之植物,其寄主植物除文獻所紀錄之台灣馬藍(Strobilanthes formosanus)及賽山藍(Blechum pyramudatum)等外,也取食大安水蓑衣(Hydrophila pogonocalyx)、無花水蓑衣(Hygrophila violacea)、易生木(Hemigraphis repanda)及翠蘆利(Ruellia brittoniana)等。黑擬蛺蝶幼蟲野外族群波動與溫溼度及雨量等環境因子並無直接關係。黑擬蛺蝶一年發生多世代且有世代重疊情形,世代波動與四季律動關係不明顯,顯示黑擬蛺蝶對環境的適應力大。黑擬蛺蝶幼蟲利用築巢以適應環境變化,應是其幼蟲良好的生存策略。且幼蟲在強風及光線強的環境下築巢率增加,降雨時則減少。Junonia iphita iphita belongs to Nymphalidae(Lepidoptera). They can be found easily in the wilderness of Taiwan. Its larva shows nest-making behavior. However, there is little literature documenting the behaviors of its larva. Therefore, the purpose of this research is to investigate the relationship between the quantities of Junonia iphita iphita’s larvae and its natural habitat, to research its nesting behaviors, and to investigate its survival strategies to adapt to the environment. I started by raising larvae in a growth chamber under a controlled temperature in order to obtain its initial information regarding its life history. In the field, I documented the numbers and the changes of larvae at each stage on different host plants and recorded the differences in its nest-making behavior in order to find out which environment factors influence the nest-making of Junonia iphita iphita’s larvae. These experiments concluded that the life history of larvae is short. The immature intaking habit showed that the larva takes various plants of the Acanthaceae. In addition to the host plants mentioned in the literature, such as Strobilanthes formosanus, and Blechum pyramidatum, Junonia iphita iphita’s larvae also live by Hydrophila pogonocalyx, Hygrophila violacea, Hemigraphis repanda, and Ruelba brittoniana, which were not listed in the literature. Through experiments, I discovered that there is no direct correlation between the population fluctuations of larvae and it’s enviroment including factors such as temperature, humidity or rainfall. Junonia iphita iphita can produce multi-generations in a year accompanying generation overlapping. There is also no obvious correlation between the generation fluctuations and changing seasons, showing that larvae can easily adapt to the environment. Junonia iphita iphita’s larvae adapt themselves to the different environments by nest-making which should be a good survival strategy. Besides, the rate of nest-making increases when larvae are under strong winds and strong lights and decreases when the rain falls.
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Two soldiers walk on a checkerboard. They can only walk one step once a time and two directions, front and left, are decided randomly. The gunshot is the column and row where a soldier is located, and one will die if he enters the gunshot area of the other. To treat the probability of winning, we first study the cases of 1×n, 2×n, 3×n, and 4×n rectangles iterately. Then we establish a general form of the probability of winning in a general n×k rectangle by using recurrence technique and generating function, respectively. Finally, we extend to the general n×m×k cuboid case to obtain the first soldier’s probability of winning.在一個長方形的棋盤中,兩士兵行走,每一次只走一步,而且上和左兩個方向是隨機的,射程範圍是所在的此行和此列,而進入他人射程範圍則死亡。探討其獲勝機率,從1×n 、2×n、3×n、4×n 矩形的情形逐步研究,並分別運用遞迴式的技巧及生成函數,導出 n×k 矩形中先走士兵獲勝機率的一般式。更進一步地,我們也獲得了n×m×k 立體空間先走士兵的獲勝機率。
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This study investigates the possibility that “Digital Buses” would actually be used in real life. In addition to the basic mathematics knowledge that I have acquired over the years, I have used “Microsoft Visual Basic” and “LEGO ROBOLAB SOFTWARE” to implement the idea as a program. It simulates the way in which a digital bus travels in a city with a rectangular grid. Various plans are tested to find the best paths for providing the most efficient, convenient and speedy transportation. This study has not only shown that “Digital Buses” are sure to be used in a modern city when wireless communication networks has developed to a certain point, but also supplied a framework for future researchers who may wish to study the optimal way in which more than one digital buses could efficiently run in cities according to their population distributions and road arguments, in order to overcome the traffic problems from the current bus systems. 本研究探討數位公車在人類未來生活中實際運行的可行性。本人以所學的數學知識進行公車路徑規劃,並透過「樂高機器人控制系統」以及Microsoft Visual Basic 軟體程式之撰寫,在棋盤式城市區域中模擬公車行駛情境,靈活搭配各種方案找出最佳路徑,達到便利快捷的高運輸效能。本研究顯示當現代化都市無線通訊網路發達到一定的程度時,數位公車的發展是可以預期的。本研究之結果可提供後續研究者繼續探討多台數位公車在實際都市中依人口分佈、道路狀況來規劃最佳行駛路徑,以解決現今機械公車無法克服之繁雜交通困境。
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Ecloping Binary Stars:Statistical Analysis of Classification VS. Celestial Positioning
This research introduces a new, more efficient method of age determination for eclipsing Binary through use of celestial Positioning . Statistical Analysis of x-y plots of eclipsing Binary Stars within our, Milky Way Galaxy were conducted in order to find the standard deviation of each eclipsing binary star’s distance from the celestial equator. Before the standard deviations could be considered for comparison, the medians from each of the three s-y plots were examined. There medians had to show a value close to zero in order for the standard deviations to be relevant. A value close to zero indicates a proportional and symmetrical plot with an equal distribution of stars on each side of the plot. All three plots generated indicted a median no greater than 1/100 in distance from the celestial equator. A low standard deviation indicates young relative age. The statictical analysis calculated standard deviations of 2.41 for W Ursae Majoris, 1.77 for Algol, and 1.20 for Deta Lyrae. The statistical analyses were then compared to the previously made visual and mathematical analyses conducted in previous years’ studies. All analyses conducted conclude that W Ursae Majoris is the oldest type and Beta Lyrae is the youngest type of eclipsing binary star. This method can be implemented to greatly reduce time in studying the relative ages of individual objects and types of objects within our Milky Way Galaxy.
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流行病的傳染過程如同一個無尺度網路,但較一般無尺度網路有著更多的變數而明顯差異,因此無法直接應用一般的無尺度網路模式來描述其傳染途徑。我建立一個新模式「無尺度流行病模式」,經由比較模擬結果與疾病管制局的數據,證實此「無尺度流行病模式」是正確與確切可用,且適用於短期暴發性傳染病與長期流行病。SARS案例研究結果,顯示影響SARS疾病傳染因子的大小是:ψ>m>γ。其中降低ψ值可使SARS確定病例至5月31日止降為143人(減少確定病例190人,相當於減少死亡21人);僅提高防疫使5=γ,亦可使確定病例減至307人(減少確定病例26人,相當於減少死亡3人)。因此強化隔離措施以減少傳染天數最為重要,且可以有效控制每日SARS新增病例,避免發生高侵襲率的現象。HIV/AIDS案例研究結果,獲知採用ψ值來進行月份模擬,則至 2005年12月HIV(+)與AIDS分別為可減少2,715與285人。而進行年度模擬結果,則至 2014年底HIV(+)與AIDS分別為可減少41,936與5,328人。無尺度流行病模式可以協助所需警戒的程度與政策決定的計畫結果。因此無尺度流行病模式在幫助政府評估社會經濟成本與健康憂慮上的有用之工具。當面臨一個全然無知的新病毒的侵襲時,如何減少死亡與傷害人數?是本研究之最終目的。因此,本研究結合了流行病、無尺度網路與灰預測,建立面對病毒侵襲,一個確切可行的對抗無尺度流行病傳染新方法,並詳細說明運作流程。\r \r \r The course of epidemic infections resembles a scale-free network. However, they are different due to more variables in the epidemic infection. Therefore, the model of scale-free networks is not enough to satisfy the reality epidemic infections. In this study, I propose a new the Scale-Free Epidemic Model. Comparison of the simulation results with Taiwan CDC report data for SARS and HIV/AIDS cases show that the Scale-Free Epidemic Model is accurate and useful. This model can be used in the short-term outbreak of infectious diseases and for the longer-term epidemics. In the SARS case study, the results show that the sequence of effect of the epidemic factors was: ψ>m>γ. The SARS confirmed cases would decrease to 143 cases (reduced 190 confirmed cases or 3 death cases) calculated to May 31, 2003, if the average infection time was reduced to two days (an optimum value of ψ). Therefore, vigorous action in isolation quarantine and treatment for SARS cases is most effective policy; the number of new cases and the attack rate would also decrease. In the HIV/AIDS case study, the simulation results of the Scale-Free Model indicates that the reduced numbers of HIV(+) and AIDS in the monthly simulation calculated to December 2005 are 2,310 and 361 and the annual simulation by December 2014 are 27,161 and 3,710. The Scale-Free Epidemic model can help determine the level of caution needed and the projected results of policy decisions. Therefore it is a useful tool in assisting the government to balance socio-economic and health concerns. The fight against a new epidemic and how to reduce the number of deaths is the main purpose of this study. So, a new method to fight against epidemics is proposed. Detailed procedures of this method are explained.
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天羅地網-雷射光線之反射路徑與正n邊形完全圖之關係探討
在正n邊形的n個頂點各放一面鏡子,並將其中一個鏡面順時針轉動90°/n,將雷射光線沿該點切線方向射向此鏡面,使光線在正n邊形各頂點的鏡面間反射,本文主要在探討光線在各鏡面間反射路徑之規律性與其應用,研究分為兩大部分:一、將雷射光線射向一順時針調整角度θ=90°/n的鏡面且其餘鏡面皆不轉動之情形下,探討雷射光線的反射路徑之規律性及尋找正多邊形邊數與反射數間的關聯性。二、在正n邊形的n個鏡面中,每個鏡面可依順時針或逆時針旋轉一個角度θ=90°/n或是不轉動。此部分我們只針對n為偶數的情況去探討,我們採用數學上函數的對應方式取代了物理上反射原理的路徑操作,由數學的模式去探討鏡面調整的規則,擬訂出適當的策略調整鏡面的轉動,並找出最大反射數。
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This study is to investigate whether colony of the spiny-weaver ant, Polyrhachis dives, have biological clock so as to observe the locomotion activities of the ants in the nest and find out if the Light period will interfere the rhythm. The conclusion is the colony of the ants get the rhythm is 23.8 hours during in L:D=12:12.There are ants not significant difference between large colonies and small colonies. While in Dark (D:D)the ants appears free running with 23.1 hours as the rhythm, so, the colony of the ants has obvious light-rhythm movement, showing that the biological clock will act on group and being controlled by light period. 本研究是在探討黑棘蟻 (polyrhachis dives) 聚落是否有生物時鐘(biological clock),以觀察黑棘蟻在巢裡的活動情形,找出週期並探討光是否會影響週期。結果觀察出黑棘蟻 的聚落在有光的時候(L:D=12:12)以23.8 小時為週期,沒有光的時候(D:D)黑棘蟻仍呈現自由律動(free running),以23.1 小時為週期,所以黑棘蟻的聚落有明顯的日週律動,顯示生物時鐘能作用在聚落上,且受光週期之調控。
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