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目前一般市面上所賣的定時器,概略可分:單點單段定時控制,或幾段單點定時控制等幾種,在構造上大部分均採用機械式控制,很少有電子式定時控制器上市,基於此理,便構想設計一個具有多點多段隨心所欲的電子式定時器,合乎每個家庭各種電器製品的控制,甚至於控制工廠機器定時控制。
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黃麴毒素係由黃麴菌屬等多種黴菌所產生對人類或動物具有高度毒性的次生有毒代謝產物,它不僅已被證明對某些動物引起原發性肝癌,更由於流行病學之研究,顯示與人類肝癌的發生似乎具有密切的關係,是一種可怕的致癌因子。產生黃麴毒素之微菌廣佈於自然界中”無論在穀類、食物、種子,飼料等只要在環境因子適當的條件下,皆有受到該毒素感染的危險,而直接或間接影響人畜生命之安全,自 1960 年英國農場發生十萬雙火雞集體中毒後,已激發世界各國對黃麴毒素污染農產品的重視,紛紛作其污染農產品之調查。
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以相對實力的概念計算第n節點的對手Xn之實力,藉此評估對手Xn對自己的威脅程度;以函數b0判斷旁子樹選手實力升降對己身造成的優勢或威脅;由勝率一般式Pn(Q1)計算各選手晉升至第n節點的勝率;定義實力發揮度Fn(Qi,Aj)用於計算選手Qi於賽程表Aj中的實力發揮度;定義賽程表現率Sn(Qi,Aj)評估賽程Aj對選手Qi勝率的影響;分別以選手重實力、最新組重實力、累乘組重實力預測各賽程將晉級的選手;檢驗模型計算之勝率是否得以預測實際冠軍。
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在遞迴式an+2=|an+1|-an中簡單的代入幾個值,發現有九個一循環的現象。在一番巧思之下,我們先證明:函數f1(x)分別為1及-1、f2(x)=x,且fn+2(x)=|fn+1(x)|-fn(x), ?n?N, f5(x)與f6(x)圖形對稱於x=1/2,進一步證得遞迴式循環,再將初始值伸縮至a1, a2為任意實數值。解法固然令人拍案叫絕,但令我們深深著迷,決定投入大量心血在此研究的原因,乃是遞迴式an+2=β|an+1|-an,當0<β<1時,點(an, an+1)構成遞迴圖形的種種現象。 我們大量使用了函數及圖形分析的方法,定義函數fβ(cosθ, sinθ)=(sinθ, β|sinθ|-cosθ),發現f (n)β皆為 ?連續函數;?一對一;?(cosθ, sinθ)逆時針旋轉時f (n)β(cosθ, sinθ)同樣逆時針旋轉。藉由上述的性質推得遞迴圖形?在角度上稠密;?形狀與初始值無關;?初始值的改變產生相似的遞迴圖形。 在研究過程中,發現β=0.86的遞迴圖形有別於其他β值,有待未來,我們四人能一窺遞迴圖形的終極密碼。
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設計可改變溫度的儀器,觀察本氏液與醣類的反應過程,提出“氧化亞銅顆粒”的模型說明定性觀察結果與定量的檢量線關係。當Cu2O的量愈來愈多,顆粒因晶體的成長或溶質粒子的締結、聚合,粒徑愈來愈大,溶液透光率變差,電阻上升,然後Cu2O顆粒成長到接近雷射光波長附近,產生繞射,光敏電阻接受到的光量不變,致使電阻值呈現水平滯留狀態,顆粒繼續變大後,繞射現象消失,大顆與多量Cu2O,使電阻又上升,最後電阻不再上升,且更大顆的Cu2O產生不規則散射,電阻與時間關係圖有棉絮化散開現象。並以此顆粒特性推導出反應速率與溫度、濃度定量關係,再將此檢量線應用於檢測葡萄糖的濃度。
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還沒放寒假前,常聽到同學說到「魔術方塊」的速度、難度使我非常好奇,便到電動場所一探究竟,看了之後便更下定決心,研究魔術方塊的奧祕。
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在接觸到了驚人的BZ 反應後,我們開始著手研究相關實驗。首先,想藉由改變各種反應物的濃度,看看反應的結果會有什麼差別,並記錄下反應時間的平均差,以求出反應速率,並進而求得「速率定律式」,來了解反應的機制。另外,在一開始便想試試看,能否利用其他化學藥品取代原本的反應物,因為我們當然很希望能找到不同的顏色變化!此外,我們還由阿瑞尼士方程式求出log k 對1/T 的關係圖並求出活化能,驗證了阿瑞尼士方程式在振盪反應上應用的可行性。
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本專題係規劃製作一套智慧型居家管理系統,該系統包含下列六大功能:一、家電控制系統二、家庭電力控制系統三、防盜系統四、災害監控系統五、生活小秘書六、自我測試以Visual Basic 為介面,將個人電腦當作為整個智慧型系統的核心接著再透過8255 卡來擷取外部硬體設備的資料並做轉換,將其轉換的資料送至個人電腦,由個人電腦來做資料的比對及處理。電腦抓取8255 卡的訊號所做的處理,例如:家電控制系統、家庭電力控制系統、防盜系統、火災監控系統、生活小秘書、自我測試等等,再分別送至各子系統做完善的處理,展現各種功能。智慧型居家管理系統之特色如下:一、PC 為主要控制 二、即時間控 三、系統完善 四、系統全自動 五、操作方便 六、電路間單
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影響颱風雨量之因素在侵台颱風路徑預報專家系統中已有詳細的分類,卻未有颱風降雨型態的研究。為探討莫拉克如此驚人雨量的原因,我們自歷史颱風資料庫選出與莫拉克路徑相似的颱風,用各種統計法分析這些颱風之兩種降雨型態,由兩種降雨型態的差異探討颱風降雨因素之間的相關。將分析結果與各項氣象資料統整,找出由綜觀環境到颱風內部結構等和莫拉克相近之颱風,分別和莫拉克作比較來探討影響雨量之因素。由以上分析過程我們找出莫拉克的降雨型態及超大雨量與下列因素有關:暴風環流通過臺灣時間、西南氣流效應、颱風路徑及綜觀天氣條件。這些因素中,最顯著的因果關係為暴風環流通過臺灣時間越長,則颱風擺盪越明顯,強烈季風槽長時間供應水氣,於是中尺度對流不斷發展使測站累計接受降雨時間長,導致中南雨區百分比越大,造成莫拉克颱風全臺累計雨量創三十年來的最高記錄。
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What really attracts boys to girls
The purpose of this research was to challenge misconceptions about what attracts teenaged boys to girls. It has been observed that some teenaged girls hold stereotypes about boys and believe boys are only attracted to superficial qualities like beautiful hair. The aim is to investigate differences between what girls believe boys find attractive about them and what boys actually find attractive about girls. Hypothesis: There is a significant difference between what teenaged boys find attractive in girls and what teenaged girls think boys find attractive. Procedure Background reading was done to discover which characteristics are commonly used to measure attractiveness among teenagers. A survey questionnaire was used for gathering data. To gather information for the construction of the questionnaire, 4 focus groups were interviewed. The groups were asked to determine indicators of attraction and repulsion. Two separate questionnaires were designed (one for boys and one for girls), based on focus group information, with similar questions which could be used to compare results. Questions were related to personality and looks. The research was representative as 399 teenagers participated in the final survey. Results were collated in Excel tables. Percentages were calculated by using a scientific calculator and Excel. A bivariate analysis was created to examine the main question: ranking qualities that attract boys to girls. A comparison was made between boys’ and girls’ opinions from different age categories. Mean averages were calculated for this question. Other questions were analysed using mode averages translated into percentage of each gender. Graphs were designed using the values calculated. Observations/Data/Results 72% of boys prefer a girl with average looks and an awesome personality but only 37% of girls believed that to be true. The average boys from 12-14, 15-17 and 18-20 year old categories agree that confidence, humour, a nice body, politeness and intelligence are the five most attractive qualities in a girl they would consider dating. The order of these five change across the age groups but are constantly the top five, however confidence and humour always trump a “nice body”. The average 12-14 and 15-17 year old girl overrates a nice body and underrates politeness and intelligence but confidence and humour feature in their top five. The average 18-20 year old girl agrees with the boys priorities. When defining what makes a girl beautiful, 68% of boys highlight personality traits and 59% of boys mentioned physical features. When noting what repulses boys about pretty girls, more than 50% of both sexes agree that smelling bad was most off putting. 52% of boys mentioned taking drugs as unattractive yet only 23% of girls recognized this as repulsive. Conclusions The data supports the hypothesis. Confidence and humour are more important to the average boy than a nice body across all age groups. The younger the girl, the less she understands what attracts boys. 63% of teenaged girls believe that looks are more important to boys than personality. This is clearly not true. 72% of boys value a great personality more highly than good looks.
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揮發性化合物抑制水稻去白化的分子機制
植物受逆境時常釋出VOCs (Volatile organic compounds)。本研究首度發現一種VOC-月桂烯(myrcene)可抑制水稻芽鞘之去白化現象(de-etiolation)。研究發現水稻在月桂烯處理下去白化現象受抑制,是因葉綠素合成相關基因ACSF被抑制所致。同時有一些參與光合作用光反應、 碳反應基因表現也有受影響。月桂烯影響光合作用相關基因,有三種不同類型:一、黑暗下基因產物幾乎不表現,照光後才累積,累積量受月桂烯抑制,如RCA、 ISP、G3PD;二、在暗處下基因產物之累積就被月桂烯大量抑制,如ACSF,ATPS;三、黑暗下基因產物之累積受月桂烯抑制,同時月桂烯抑制照光後光誘發基因累積速率,如FNR。由基因產物累積量推測轉錄因子MYB-TF1參與月桂烯抑制去白化現象,且推測RCA、ISP、G3PD為其下游基因。VOCs含天然毒素,可抑制附近植物生長,可為天然農藥。
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