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顛倒一族

一 Motivation and Purpose: In this study, we want to completely know about “The number abc…de, which times m/n, 1≦n≦m≦9?N can get ed… cba?”, and also expect to find out “The good rule within them”. 二 Procedure:Using method of enumeration, induction to collect sample of all and beginning from two digits to get information “good rule”. When get some useful idea, put them into the following research for the step easy go on, the method try and error is a very tiresome works, especially when we deal higher digits. till enough information is obtained, we solve problem and find new one, then likewise again research steps, just the basic science research ways, we are glad have the key of these problem. 三 Result and conclusion :Those number we named “converse No.” There are two groups: S=m+n=10 and 11 S=11, then Q=m/n=9/2,8/3,7/4,6/5=4.5,2.6,1.75,1.2 S=10, then Q=m/n=9/1,8/2,7/3,6/4=9,4,2.3,1.5 Each group have four type. When S=11,Q=7/4=1.75,if converse No.each digit is a multiple of 3, then can cancellation or extension of fraction to get another 3 or 4. Growth up rule: Converse No. = type factor x heritable factor x growth factor=rx hx g S=11,r=2~5,h=9, s=10, r=1~4, h=99 一 研究目的:盼能找出”顛倒一族”的族譜。二 研究過程:確定研究題目為ab…cde×m/n=edc...ba,0≦n≦m≦9?N 求ab… cde?以窮舉法收集觀察資料,歸納演繹尋求規律。1.先觀察兩位數,分析共有顛倒對36對。2.建立乘數Q=m/n一覽表,共有27個3.設計顛倒對大/小及其商一覽表,以利觀察、歸納獲得規律。4.接著觀察三位數,共有360對,綜合二、三位數規律,找出選擇式窮舉法:9之倍數法。5.再接著找出四位數,再綜合而知另有 全調法 重現法 半調法 GCD遺傳基因法等來繁衍高位數顛倒數。6.於是依諸法找得六位數資料,得知GCD遺傳基因法為繁衍通則,完成族譜建立模式。7.研究顛倒數位數與其個數間關係式,完成研究。研究結論:1.顛倒一族有兩大類:S=10與S=11 S=m+n。2.每一大類有四型: S=10中,Q =9/1,8/2,7/3,6/4(9,4,2.3,1.5)S=11中,Q =9/2,8/3,7/4,6/5(4.5,2.6,1.75,1.2)3.每一型均有一個顛倒數,除了S=11中,Q=7/4=1.75者可約、擴分而得3or4個。4.顛倒數原則上均為9之倍數,除了Q=7/4經約、擴分可能得非9倍數者。

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埃及分數之固定項數分解問題

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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翻轉「膜」力

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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外接正多邊形法與對稱性

Motivated by Napoleon theorem, we study the properties of the triangles obtained by moving the midpoint of each side of a given trianle along the perpendicular bisector of corresponding sides, and extend the results to the case of quadrilaterals. On the other hand ,we consider the method of erecting a regular M-gon to each side of a given N-gon and joint the N centers of these M-gons to form a new N-gon. (abbreviated as CRG method),and get the following results. 1. We characterize some kinds of N-gons that can be transformed to regular N-gons via CRG method. 2. Of M,N are nature numbers with M|N, then it is possible to find a N-gon that can be transformed to a regular N-gon by CRG method. \r 3. If a polygon P is symmetric with respect to a fixed point or a fixed line, then P can be transformed by CRG to a polygon with similar symmetries. 4. If a polygon P is transformed by CRG to ′P,there exists a commonpoint G such that ΣGA=0 andΣGB=0, where A and B runs through vertices of and P′P, respectively. 本研究將拿破崙定理加以延伸。先探討由各邊中點沿中垂線延伸得出之三角形的性質並推廣至四邊形之情形條列式報告成果。另一個推廣是將給定的多邊形的每邊外接一個正多邊形,再以這些外接的正多邊形的中心為頂點造出一個新的多邊形。我們發現此幾何變換具有以下性質:(1) 「哪些多邊形能被變換成正多邊形呢?」,我們觀察出能被變換成正多邊形的多邊形其限制條件隨邊數增加而增多,並進一步區分了哪些多邊形可以被變換成正多邊形。 (2) 在將非正N邊形做變換時,不一定須外接正N邊形才能得到正N邊形,我們區分出可外接哪些正多邊形而得到正多邊形。 (3) 對給定的多邊形作此變換時,若原多邊形有點對稱或線對稱等性質,則新多邊形也將具有相同的性質。 (4) 此變換得到的新多邊形會與原多邊形共重心,亦即新舊兩多邊形內到各自的頂點向量和為0的點會是同一點。

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線蟲補捉菌Arthrobotrys musiformis 黏液相關基因之選殖與功能界定

線蟲捕捉菌Arthrobotrys musiformis 是一種可經線蟲誘導產生捕捉網來捕捉線蟲的真菌,本實驗即針對A. musiformis 的捕捉網黏液相關基因:Manosyltransferase(AH73), β-1,3-glucan transferase(AH102), fimbrin(AH121)及mannose-specific lectin precursor(AH338)進行選殖與功能界定,希望建立這方面的研究基礎,將來能應用在松材線蟲的生物防治上。首先我們大量培養A. musiformis,萃取菌絲體的DNA;接著進行聚合?連鎖反應 (Polymerase Chain Reaction,PCR) ,利用專一性引子對 (primer) 大量增幅AH73、AH102、AH121 及AH338之基因片段;增幅後的產物經過純化、選殖,定序並進行分析比對,確認增幅之序列無誤後,以 Digoxigenin (DIG) 標示當為探針,篩檢A. musiformis 的Fosmid Library﹔目前已成功選殖出AH73 之可能基因,完成AH73 之探針製備,並以其篩檢A. musiformis 的Fosmid Library﹔呈雜合正反應之選殖株 (clones) 將以散彈槍方法(shotgun)定序,作序列組合,探索相關的基因;接下來用 Rapid Amplification of cDNA Ends(RACE) 做出互補DNA (complementary DNA , cDNA) 全長度後;最後建構基因缺失株,驗證此基因所調控的生理以及生化機能。 Nematode trapping fungus Arthrobotrys musiformis can capture nematodes by producing adhesive nets when nematodes go through. Many kinds of nematodes, including pine wood nematode (Bursaphelencus xylophilus), can be captured. Pine wood nematode causes serious pine wood disease. Therefore, A. musiformis has the potential of biocontrol in pine wood nematode. Our research focused on adhesion and adhesive relevant genes of A. musiformis :Manosyltransferase (AH73), β-1,3-glucan transferase (AH102), fimbrin (AH121), and mannose-specific lectin precursor (AH338). We try to clone these genes and carry out functional analysis. In order to achieve this goal, we used specific primers derived from previously obtained complementary DNA (cDNA), by Polymerase Chain Reaction (PCR) to amplify these genes and gained adequate quantity of genomic DNA products. After sequencing and verifying of the identity of the genomic DNA, we use Digoxigenin (DIG) to label them and use them as probes to screen the constructed A. musiformis Fosmid Library. Currently, the Southern colony hybridization is undergoing. The positive Fosmid clones against the specific probes will be sequenced completely by shotgun library to monitor the existence of adhesion related gene cluster. After working out the full length cDNA of these genes, we will use them to construct replacement vectors to knockout the adhesion related genes, creating mutants and further verify their functions through genotype or phenotype bioassay.

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灰色預測在雨量長期趨勢分析之應用

灰色理論近來廣泛應用於各行各業的管理資訊科學上,本研究乃應用灰色理論的一階微分中輸入變數為一項之 GM ( 1 , 1 )模型,來預測台灣中部地區土石流主要因素雨量的月平均量值。本文運用三筆以上的歷史資料,作最近一年歷史性資料的預測,藉以驗證獲得其誤差(±△e)之校止參考依據值,比利用殘差檢驗所得的誤差校止數據,更能修止出精確的預測值,接著再做台灣中部雨量未來之預測,以作為未來雨水、土石流防治之參考 · 為了能迅速產生所要的灰色預測值,研究中並以 VB 程式語言及以Petri-net分析其動態處理行為,藉 GM ( 1 , 1 )模型的專屬處理支援程式,以做為未來雨輦自動化處理警示與預測之支援機制。Recently Grey Theory has been widely applied to management information science in all kinds of areas. This research applies the first Level differential of the Grey Theory to put a variable in GM( 1,1) model to forecast the monthly average value of the most common precipitation, in the midland Taiwan earth-stone flood zone. This paper uses more than three historical data to forecast the most recent year’s historical data, which can be used to verify and acquire referential correction data of its errors ( ±△e). The aforementioned method can correct forecast data more precisely than the differential inspection. In addition, this method can then forecast future precipitation in midland Taiwan earth-stone flood zone and the results can serve as reference for future precipitation control. To rapidly receive the needed Grey forecast values, the research analyzes its dynamic process method by utilizing VB program and Petri-net to build a dedicated process-support program of GM( I , 1) model. This program will serve as a support mechanism for future automatic precipitation warning and forecast.

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電話網路全方位監控系統

In this paper, we use telephone network to remote-control household appliances and monitor security system through the implementation of software and hardware. The purpose of developing this system is to build up a system that makes everyone take advantage of the telephones through pay phone network everywhere as and when he needs to set up the household appliances, meanwhile two-ways system of monitoring household security. In addition, due to the advances of communication technology and the remarkable boom of those products, the popularity of cell phones for local people is developing tremendously. We can link the portable cell phones up to the household appliances and monitoring household security through the offer network of communication companies. This system adopts public telephone network via multiple frequency to receive KT31 70 IC which is connected to EM78P45 i p Chip. And then the Chip is connected to the driving external circuit in order to control electric appliances, sensors on doors and windows. The utilization of LEPROM (93C66) memory to set up telephone and mobile phones number equips the telephone network with two-ways system of remote-controlling electric appliances and monitoring household security. In the part of controlling electric appliances, a monitor is used to display the status of electric appliances, to control the appliance switches and to set up the timer. In the part of monitoring household security, we use the system to receive the instant images of the house and to report on the closing or opening of doors and windows. The system will be informed on any occurrence of abnormalities. The memory of the system can record and update new data at any time and is able to set up twenty sets of telephone and mobile phone numbers. Besides, the system adopts identification codes to avoid malfunctioning and thus upgrade system reliability.本文旨在應用電話網路作遠端遙控家用電器及防盜保全歟控系統軟硬體之規劃與設計 。本系統研製的目的,是希望建立一套系統,讓每個人不管身置何處,都能利用電話透過公眾電話網路,輕易地控制家中的電器設備及進行環境設定,以達到控制家電及防盜保全之雙向監控系統。此外,由於通訊的進步與通訊產品的熱賣,使國月雍有手機的普遍性相當高,若能透過隨身攜帶的手機,經由通訊業者所提供的網路通訊管道,連結到家庭自動化與防盜保全系統亦可達到進行遠端遙控的目的,彌補出門在外無法使用室內電話的空檔。本系統利用公眾電話網路經複頻接收 IC ( KT3 170 )連接至單晶片( EM78P45 IP ) ,透過單晶片驅動外部電路與家中電器及門窗的監視感測器連接,再利用 EEPROM ( 93C66 )記憶體設定電話及手機號碼,藉由電話網路傳輸,以達到控制家電及防盜保全之雙向監控系統。在家電控制部份,採用顯示器可隨時瞭解家電使用狀況及控制其開啟或關閉,且可設定使用時問。在防盜保全部份,可隨時監控家中門窗,若有異狀可即時通告。記憶體可隨時記錄或更新資料,並可設定二十組電話及手機號碼。此外,本系統採用確認碼設定,可防止產生誤動作,系統可靠性高。

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印度莕菜由沉水型轉為浮水型的支撐機制探討

The special life cycle of the Nymphoides indica: The veins and petioles of the pleustonic leaves can asexually reproduce adventitious buds. Pleustonic adventitious buds will change the density of the plants and sink into water. When the root of submersible plants attaches to the bottom of the pool, they will extend stems to the water surface and resume the life cycle. Reticulate sigmons and astral sclerenchyma appears in the process of transformation. Astral sclerenchyma merely appear in the species of which its leaves float above the water surface, and Nymphoides sp. are the most obvious. The cell wall thickness of astral sclerenchyma is even. The cells are hollow and full of water, and they will utilize water to change turgor between axes and spines. This is also proved in imitating experiments. The reticulate sigmons are frequently seen among aguatic plants, and the horizontal structures prevent air space from collapsing. These two structures make the thin stems of Nymphoides indica sustain the leaves instead of being crushed by the floating water. 印度莕菜 ( Nymphoides indica )獨特的生長週期:浮水型葉的葉脈和葉柄可以無性繁殖不定芽,浮水型的不定芽會改變植株的密度而沉入水中,當沉水型植株的根系在池底固著後,便會以莖延伸出水面,再次展開浮水型葉的成長週期。轉變過程中會出現網狀的橫膈和星狀厚壁細胞。星狀厚壁細胞僅出現於葉片需由水中浮出水面生長的植物種類,而莕菜屬植物更明顯。星狀厚壁細胞其細胞壁厚度均勻,細胞中空且充滿水分,會利用水分在中軸與突起的棘間移動來改變膨壓變化,在模擬的實驗中也得到證實。網狀的橫膈在水生植物中是較常見到的構造,水平方向的支撐可以讓氣室不會塌陷,兩種構造的作用下使得印度莕菜細長的莖能夠支撐葉片,不會被流水沖斷。

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對抗無尺度流行病傳染之新方法

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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以圓錐套和熱電半導體來改善傳統電風扇效能的研究

電風扇在炙熱的夏日中為冷器以外不可或缺的生活用品。一個典型的電風扇是由架在可調高度鐵柱上的馬達及風扇構成。現行傳統電風扇有幾個缺點,一、馬達風扇(即重心)位置高,有易傾覆的缺點。二、風力分散,風速不高。三、吹出不可調室溫溫度的風。四、外觀呆板,傳統無奇。五、多噪音等。本研究根據這幾點傳統電風扇缺點,試著設計新的電風扇。首先將柱子移除使重心降至接近地面處。接著根據連續方程式(continuity equationρ1A1V1 =ρ2A2V2)製作圓錐狀「號角」裝置套於電風扇上以集中風力並減少噪音。最後企圖使用熱電半導體的致冷器降低輸出風的溫度。研究結果發現號角裝置有效達到預期的集中風力增加範圍目的。不幸發現以熱電半導體降溫的方式效率低且耗損過多能量所以可行性較低。雖然沒有降溫功能,本電風扇仍較傳統電風扇多出許多好處,例如加強的安全性、集中的風和強大擴充性。號角裝置可包含空氣清淨甚至音箱功能充當喇叭。Electric fans are a necessity during summer, especially in a hot and humid place such as Taiwan. A typical electric fan is primarily composed of an electric motor with fans mounted on a strut with user adjustable elevations. This setup presents several problems, including (a) the danger of an accidental tip-over due to the fan's elevated weight center (the heavy motor), (b) high wind dispersal rates, (c) room temperature winds, (d) excessive noise and (e) old, antiquated exterior appearance. This particular study attempts to alleviate all these problems. First the weight center is lowered to ground level by removing the entire strut and placing the motor close to the floor. Next by using calculations from the continuity equation(continuity equationρ1A1V1 =ρ2A2V2)a cone shaped “horn” device is placed over the fan in order to concentrate the wind, effectively increasing its speed while decreasing the audible noise level. Finally, an attempt was made to lower the temperature of the air in the interior of the horn by the placement of a thermoelectric semi-conductor cooling device. Our results were that the horn device worked, significantly lowered the wind dispersal rate and achieved an important objective. However, the thermoelectric cooling solution proved to be highly inefficient unless accompanied by precise wind speeds. Even without the cooling function, this new electric fan still has many distinct advantages over traditional fans such as improved safety, concentrated winds and high expandability. For instance, filters can be integrated to purify air, even an audio speaker can be made into the form of this fan.

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熱線式渦流流量計

流量計在實驗室與工業領域裡是重要的儀器,如今已經有數十種依不同物理原理而發展出來的型式,可以配合多變的環境需求與測量條件而使用。然而,各種流量計所適用的範圍備受侷限。本研究主要目的在發展一種熱線式的渦流流量計,供給氣體之流量量測之用。透過自行製作儀器與設備:熱線測速儀(包括探針、探棒及電子處理器)和渦旋產生器(管道中含一三角形截面之鈍體,當流體通過時,在後方尾流產生週期性渦旋逸放)。由於熱線測速儀擁有偵測流體運動時高頻動態變化的能力(約為20000 Hz 以內),因此結合熱線測速儀與渦旋產生器,經適當的設計與調校,可以測得在不同流體流速時渦旋產生器的三角截面鈍體後方渦旋逸放的頻率。由於渦旋產生器的截面面積為固定值,因此可以從而計算出流量與渦旋逸放頻率的關係。經由嚴格的校準與驗證步驟,本研究的結果顯示自製的熱線測速儀擁有極佳的渦旋頻率偵測能力,所量測到的校準曲線顯示渦旋產生器的三角形截面柱所產生的渦旋逸放頻率與流量成線性關係。為了降低誤差,建議在0 ~ 40 CMM 之量測範圍內分成三條方程式來代表不同範圍內的校準曲線,最大誤差僅在5%以下。若需使用在不同的流量範圍時,僅需改變渦流產生器和幾何尺寸,以使渦旋逸放頻率適合於熱線測速儀的動態響應範圍即可。倘若商品化之後,可以實際應用於風扇流量量測、引擎進氣埠流量的測量等等應用。熱線測速儀本身也可作為風速計,適用於各種場合之風速量測。Flow meter is a instrument that is vital to the laboratory as well as the industrial related field. Based on different physical principles, tens of models that work in harmony with the diverse environmental demands and measurement conditions are developed to date. However, the application of varied flow meters is still under severe restriction. The purpose of this study is to develop a hot-wire type of vortex shedding flow meter for the use of flow rate measurement. Through the home-made apparatus and device, the hot-wire anemometer (includes probe, stem and electronic processor) and the vortex generator. (duct that contains triangle’s section of the bluff body. When fluid passes through, the wake behind produces periodical vortex shedding.) The ability of hot-wire anemometer when it detects the fluid moving changes of high-frequent movement is within 2000Hz, after appropriate design and adjustment, the combination of hot-wire anemometer and vortex generator may investigate the frequency of different flow rate that generated from the vortex shedding behind the bluff body of triangle section. The section area of vortex generator is constant value, thus it can calculate the relationship of flow rate and the frequency of vortex shedding. By means of strict calibration and test procedure, the results reveal that home-made hot-wire anemometer has excellent ability to detect the frequency of vortex shedding. The calibration curve indicates a linear relationship between the frequency of vortex shedding and flow rate. In order to reduce inaccuracy, it is suggested to classify three formulas to represent the flow rate that ranges from 0 ~ 40 CMM. The greatest inaccuracy is under 5%. When applied to different flow rate range, it only has to change the size of vortex generator only if the response frequency of hot-wire anemometer suit for the range of frequency of vortex generator. After commercialization, it can be applied to measure the flow rate of fans, flow rate of intake valve of engine, etc. Hot-wire anemometer also served as anemometer, which can be applied to wind velocity measurement in any situation.

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魔術猜牌

本研究是藉由數學手法探討;如何由一疊36 張四種花色的撲克牌中,尋找出保證可猜中最多張花色的方法。研究過程是以在適當的猜牌時機,以鴿籠原理、邏輯推理、二進位、分析與歸納……等數學原理與方法,搭配巧妙的策略運用而達到目的。猜牌方法:先約定好猜牌規則,助手將36 張牌背圖樣相同但非對稱的撲克牌,以旋轉牌背的方向傳達訊息。在本研究中得出利用數學原理與方法可「經由巧妙的猜牌方法保證可以猜中26 張花色」,並提供後續研究者利用本研究之結果繼續深入探討與研究。 The study is mathematically based with reasonable explanations behind it. We are to correctly guess as many cards as possible from a deck of 36 cards, with random numbers and four different suits. We will apply mathematical methods, such as pigeonhole principle, logic inference, binary system, and analytical reduction, upon right timing. Using careful arrangement of the principles and reasoning, we can reach our ultimate goal. To state guessing: Conference between the guesser and the assistant about the guessing rules, the assistant will have 36 cards with the same exact pattern on the back but not symmetrical. The pattern of the cards will be different when rotated 180o. The only communication between the two is by rotating cards. In the process we will obtain mathematical theory and methods assuring 26 cards correctly guessed, and the study is for further and deeper discussion.

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