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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

少量連串下最適設計參數值之決定 / The Decision of the Best Fitted Design Parameters on Small Runs

嚴珮文, Yen, Pay Wen Unknown Date (has links)
管制圖之經濟模型首由Duncan(1956)提出,自此之後陸續有學者致力研究經濟管制圖,包括X-bar管制圖、S管制圖等。但R管制圖之經濟設計目前尚無人提出。而在實務上,部份產業可能由於產品過於昂貴,或者產品的製造時間所需甚長,而使得品檢時所抽取的樣本數無法達到25個,這時若採用傳統的管制圖來分析製程,將無法顯示製程真正的狀態。因此本研究首先探討少量連串下X-bar和R管制圖之製作原理,並計算及整理出較完整的少量連串下X-bar和R的管制係數表。接著假設非機遇因素只影響製程運用Banerjee和Rahim(1987)的更新理論方法,建立少量連串情形下的R經濟管制圖。再利用最佳化方法,即可求得最適設計參數值。於是,少量連串情形下的R經濟管制圖得以建立。最後,我們將舉一個例子來說明如何獲得最適設計參數值、決定關鍵參數,以及少量連串情形下R經濟管制圖之建立與應用。
22

田口方法中SN比與損失函數之研究 / The Research of SN Ratio and Loss Function in Taguchi's Method

黃藝美, Hwang, Yih Mei Unknown Date (has links)
近年來,田口方法的應用推廣與發展已經蔚為一股風潮,企業界許多設計工程師、生產現場的技術人員均普遍地使用田口方法,將品質設計於產品與生產製程之中,期能在商場上持續發展,並佔一席之地。然而,在以往田口方法的應用實例中,參數設計之因子水準的選取大都仰賴工程師憑著經驗來決定,但是經驗常會造成實驗的偏差,有鑒於此,本論文除了針對田口方法的使用做進一步的研究,並提出一套根據統計理論所推導出來的方法來協助工程師,使其在參數設計時對各因子水準的決定有一參考的依據,同時,為使其廣泛應用,本研究亦考慮到其它工業界常用的分配,而不再只侷限於常態分配。此外,本論文又針對SN比與損失函數之間的關係做進一步的討論,以使工業界能更深一層體會田口方法的優點及參數設計的目的。最後,本論文則研究非常態分配對損失函數及SN比估計值的影響情形,並表列各不同分配在α值給定之下,應如何決定樣本數(sample size)值,以使常態分配的假設更為合理。
23

可贖回區間雪球型結構債之評價與風險管理 / Pricing and Risk Management of Callable Snow Range Note

高于晴, Kao,Yu Ching Unknown Date (has links)
本研究使用Lognormal Forward LIBOR Model(LFM)利率模型,針對可贖回區間雪球型結構債進行評價與風險管理,一般評價可贖回商品常使用樹狀模型,但由於LFM模型在機率測度轉換後為非馬可夫隨機過程,樹狀之節點會以指數遞增且無法重合,故並不適用;此外,本商品計息方式為路徑相依型,無法求得其封閉解,因此本研究使用Longstaff and Schwartz(2001)所提出的最小平方蒙地卡羅法,來處理同時具有可贖回與路徑相依特性的商品評價與避險;至於結構債存續期間內之每日指標參考利率,本研究使用Brigo(2001)之漂移項內插法求算非標準期間遠期利率,以計算每季之應計配息與商品價格;最後,利用已拋捕的利率平價理論估計歷史遠期匯率,以模擬台幣計價之國外遠期利率動態,進而求算轉換為Quanto後之商品理論價值。 此外,關於可贖回區間結構債的風險管理,由於本研究之商品價格函數不具有連續性,若在蒙地卡羅法之下直接使用重新模擬的方式來求算避險參數,其結果較不準確,而Piterbarg (2004)對於計算可贖回區間型利率商品之避險參數時,建議採用能使價格函數平滑化之Sausage Monte Carlo,故本研究分別對ㄧ般蒙地卡羅與Sausage Monte Carlo進行敏感度分析,而研究結果發現Sausage模擬法所計算之避險參數模擬標準差較小,其模擬結果較精準。
24

悅趣化學習對於高齡者注意力之影響分析 / Analysis of the Effect of a Serious Game on the Attention in the Elderly

顧竣翔, Ku, Chun Hsiang Unknown Date (has links)
台灣目前已邁入高齡化社會,因高齡人口持續攀升,面對中高齡者認知能力衰退,我們提議利用遊戲的方式進行注意力訓練。相較於一般以娛樂為主要目的的遊戲,悅趣化學習遊戲(Serious Game)是在遊戲設計除時以娛樂為目的外,另附加學習目標,這種遊戲設計方式常廣泛運用於教育、軍事、健康、都市規劃、宗教、工程與政治等領域上,以達成某種訓練或觀察目的。我們以心理學理論為基礎,透過悅趣化學習遊戲在平板電腦上設計了一個系統,邀請年長者分為兩組來擔任此一系統的受試者,並觀察使用我們所設計的遊戲系統前後其注意力變化的狀況。我們在此系統上進行了視覺搜尋(Visual Search)和注意力網絡作業(Attention Network Task, ANT)的前後測驗,並加入了自適應性(Adaptive)及導入干擾(Interference)以觀察受試者排除干擾的狀態。我們觀察此系統是否能影響測試者的認知能力與其影響的程度,並比較受試者之注意力在實驗前後變化是否因遊戲系統而改變。而經過實驗後共有21位高齡受試者完成所有實驗流程,實驗組的受試者經過分析後發現他們在視覺搜尋的在正確率以及在注意力網絡作業中的正確率、警覺性分數和導向性分數皆有顯著的改變,而在實驗後透過問卷調查另可發現高齡受試者對於遊戲學習亦是給予正面的回饋且有意願繼續使用。因此我們認為我們所設計的悅趣化學習遊戲系統能提升高齡受試者的使用意願並進而有效提升其注意力。 / Since the last decade, Taiwan has entered the aging society. However, the proportion of the elderly population has continued to increase in recent years. Our primary purpose is to use serious game as a means of training the attention of the elderly and delay the decline of cognition. Serious game has a primary purpose other than pure entertainment and has been used in the past for various applications such as national defense, education, scientific exploration, healthcare, emergency management, city planning, engineering, religion, and politics. Our goal in this work is to design a customizable serious game based on cognition psychology on the Android tablet PC platform for the elderly. We invited 21 elderly subjects to play the game and perform tests done before and after the playing. In the pre- and pro-tests, we adopted a Visual Search task and the Attention Network Task (ANT) tests to study how the proposed serious game can affect the cognition abilities, especially attention, of a subject. The experimental results reveal that the accuracy of visual search, accuracy of attention network test, scores of alerting and orienting of the participants in the experiment group have significantly improved after the trainings on the serious game system. We also have received positive feedback on the gameplay from the participants, which shows that the proposed system is well accepted and can serve as an effective means for cognition training.
25

可轉債交易策略實證研究 / The empirical study of convertible arbitrage

鍾明希 Unknown Date (has links)
可轉債套利,為避險基金常用的操作技巧。其操作方式,為買進一可轉債,賣出若干標的股票。若是放空標的股數計算正確的話,未來不論標的股價上漲或下跌,投資組合都會有獲利,而本文目的為計算出所需放空的標的股數。 本文使用CRR(1979) 和Derman(1994) 模型,在經過路徑相依條約調整後,使用OAS參數做校準,以求得所需放空標的股數。在實證方面,本研究選取鴻海一(23171)、聯強一(23471)、佳能一(23741)做研究,結果顯示經校準過後所計算出的避險參數值,效果可用於可轉債套利操作所需,且兩個模型的效果並沒有顯著的差異。此外,可轉債的流動性對於模型計算避險比率的精準度,也沒有顯著的影響。
26

電源轉換器外部零件參數最佳化設計之研究

郭昭貝 Unknown Date (has links)
為了提升競爭優勢與生產能力,並進而達到永續經營的目的,突破現況、持續改善產品品質、降低產品成本與服務成本則成為提昇競爭力的重要因素之一,因此產品在設計開發階段就必需要考量品質與成本的問題。 本研究以電源轉換器為對象。該電源轉換器目前已設計完成且已通過美國UL安規認證,並已在國內量產銷售,但因為該電源轉換器的溫升及其變異很大,仍然會導致該產品的壽命過短,因此降低電源轉換器的溫升及其變異是一急需解決的問題。 透過了田口與實驗設計的方法規劃及進行實驗並收集數據。並利用十二種分析方法(包括:田口方法、主成份分析、主成份+倒傳遞類神經網路+基因演算法、主成份灰關聯+倒傳遞類神經網路+基因演算法、指數型理想函數+倒傳遞類神經網路+基因演算法、MSE方法、MSE方法+倒傳遞類神經網路+基因演算法、SUM方法、SUM方法+倒傳遞類神經網路+基因演算法、重要零件加總法、重要零件加總法+倒傳遞類神經網路+基因演算法)對實驗數據進行分析,以決定最適因子水準組合。 由改善後的確認實驗得到:雖然平均溫升下降的程度不大,然而大部份量測點的溫升標準差都顯著變小了。因此本研究在降低該電源轉換器溫升變異的效果十分顯著。對於電源轉換器的生產者而言,品質提升就是提升銷售量的保證,因此本研究所得到的最適因子水準組合,雖然產品在成本上有些微的增加,但品質改善後之產品將可為生產者帶來更多有形與無形之利益。
27

利用調適性管制技術同時監控製程平均數和變異數 / Joint Monitoring of Process Means and Variances by Using Adaptive Control Schemes

陳琬昀 Unknown Date (has links)
由近期的研究中發現變動所有參數的管制圖在偵測小幅度偏移時的速度比起傳統的舒華特管制圖來的快,許多文獻也討論到利用調適性管制技術同時監控製程的平均數和變異數。而在這份研究中,為了改善現有管制圖的偵測效率,依序提出了U-V管制圖以及Max-M管制圖來偵測單一製程與兩相依製程的平均數和變異數。採用AATS及ANOS來衡量管制圖的偵測績效,並利用馬可夫鏈推導計算得之。透過兩階段的範例來介紹所提出的管制圖的應用方法並將VP U-V管制圖、VP Max-M管制圖與FP Z(X-bar)-Z(Sx^2)管制圖加以比較。從所研究的數值分析中發現VP Max-M管制圖比另兩種管制圖的表現來的好,再加上只需要單一管制圖在使用上對工程師來說也較為簡便,因此建議Max-M管制圖値得在實務上被使用。 / Recent studies have shown that the variable parameters (VP) charts detect small process shifts faster than the traditional Shewhart charts. There have been many papers discussed adaptive control schemes to monitor process mean and variance simultaneously. In the study, to improve the efficiency and performance of the existing control charts, the U-V control charts and Max-M control charts are respectively proposed to monitor the process mean and variance for a single process and two dependent process steps. The performance of the proposed control charts is measured by using adjusted average time to signal (AATS) and average number of observations to signal (ANOS). The calculation of AATS and ANOS is derived by Markov chain approach. The application of the proposed control charts is illustrated by a numerical example for two dependent process steps, and the performance of VP U-V control charts, VP Max-M control charts and FP Z(X-bar)-Z(Sx^2) control charts is compared. From the results of data analyses, it shows that the VP Max-M control charts have better performance than VP U-V control charts and FP Z(X-bar)-Z(Sx^2) control charts. Furthermore, using a single chart to monitor a process is easier than using two charts for engineers. Hence, Max-M control charts are recommended in real industrial process.
28

企業實質價值之研究--模糊實質選擇權模型 / The Research on Real Value of Enterprises --The Fuzzy Real Option Model

錢家驊, Chien,Chia Hwa Unknown Date (has links)
本研究以Schwartz與Moon(2000)提出的實質選擇權模型為基礎,再引入模糊理論,建立模糊實質選擇權模型。太陽能產業的益通為樣本公司,進行參數估計,並使用蒙地卡羅模擬,估計益通的合理價值。經過敏感度分析更進一步瞭解,影響公司價值最重要的因子為期初收入成長率與成本。 將本模型應用到其他電子產業,發現公司的股價常有遭到市場高估或低估,而偏離真實價值的情形發生。因此本研究建立一套投資策略,並參考模型估計的合理價格為投資的依據,希望能夠賺取價差。策略模擬的結果,獲利能力明顯優於長期持有的方式,也證明了本模型的實用性。 / In this study, we use the real option model from Schwartz and Moon (2000) as the basis, and then combine it with fuzzy theory to create Fuzzy Real Option Model. This study takes one company in solar power industry - E-TON as the sample company to conduct the parameter estimation. We also adopt the Monte Carlo Simulation method to assess the reasonable value of E-TON. After the sensitivity analysis, the results show that initial rate of growth in revenues and cost are the most important factors which influenced on the value of a company. Furthermore, we apply this model to other companies in electronics industry and discover that the stock prices are often overvalued or undervalued by the market. Therefore, we develop a set of investment strategies for people who want to make profits from the difference of prices. The result of strategic simulation shows that profit is apparently better than the way of buying and holding, and it proves the practicability of this model as well.
29

基於形態轉換的多種表情卡通肖像 / Automatic generation of caricatures with multiple expressions using transformative approach

賴建安, Lai, Chien An Unknown Date (has links)
隨著數位影像軟、硬體裝置上進步與普及,普羅大眾對於影像的使用不僅限於日常生活之中,更隨著網路分享概念等Web技術的擴張,這些數量龐大的影像,在使用上更朝向娛樂化、趣味化及個人化的範疇。本論文提出結合影像處理中的人臉特徵分析(Facial Features Analysis)資訊以及影像內容分割(Image Content Segmentation)及影像變形轉換(Image Warping and Morphing)等技術,設計出可以將真實照片中的人臉轉換成為卡通化的肖像,供使用者於各類媒體上使用。卡通化肖像不但具有隱藏影像細節,保留部份隱私的優勢,同時又兼具充份擁有個人化特色的表徵,透過臉部動畫的參數(Facial Animation Parameters)設定,我們提出的卡通化系統更容許使用者依心情,來合成喜、怒、哀、樂等不同表情。另外,運用兩種轉描式(Rotoscoping)及圖像變形(Morphing)法,以不同的合成技巧來解決不同裝置在限定顏色及效果偏好上的各類需求。 / As the acquisition of digital images becomes more convenient, diversified applications of image collections have surfaced at a rapid pace. Not only have we witnessed the popularity of photo-sharing platforms, we have also seen strong demand for novel mechanism that offers personalized and creative entertainment in recent years. In this thesis, we proposed and implemented a personal caricature generator using transformative approaches. By combing facial feature detection, image segmentation and image warping/morphing techniques, the system is able to generate stylized caricature using only one reference image. The system can also produce multiple expressions by controlling the MPEG-4 facial animation parameters (FAP). Specifically, by referencing to various pre-drawn caricature in our database as well as feature points for mesh creation, personalized caricatures are automatically generated from the real photos using either rotoscoping or transformative approaches. The resulting caricature can be further modified to exhibit multiple facial expressions. Important issues regarding color reduction and vectorized representation of the caricature have also been discussed in this thesis.
30

遺傳演算法在門檻自迴歸模式(d,r)值估計的應用 / The Application of Genetic Algorithms in Parameters (d,r) Estimation of Threshold Autoregressions

張新發, Chang, Sin Fa Unknown Date (has links)
近幾年來,非線性時間數列分析有快速的發展。其中的門檻自迴歸模式(SETAR),以具有許多線性ARIMA模式所不能配適的特性而受到重視。但是,自1978年Tong建立SETAR模式以來,門檻參數估計的問題一直是SETAR模式在發展應用上的一個瓶頸。本文將探討以實數編碼遺傳演算法,結合統計學上的模式選取準則,建構SETAR模式門檻與延遲參數估計程序的可行性。並從這個基礎上,進一步地研究較精確的門檻參數估計法。 / Non-linear time series analysis has rapidly developed in recent years. Self-exciting threshold autoregression(SETAR) model of non-linear time series models is attentive, because it has some characters which linear ARIMA model fail to fit. But, It has not yet been applied widely because the question of estimation of threshold parameter limits its development and application since Tong proposed SETAR model in 1978. In this paper, we will study the feasibility which constructs a procedure of estimation of SETAR's threshod and delay parameters with real-coded genetic algorithm and statistical criterion of model selection, and develop a more precise estimation of threshold parameter in the basis.

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