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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.
61

簡明三維供應鏈規劃整合模型:以半導體晶圓代工業為例

陳奕光, Chen, Yi-Kuang Unknown Date (has links)
本文提出一供應鏈規劃(Supply Chain Planning, SCP)整合的簡明模型,該模型能夠協助晶圓代工公司達到供應鏈規劃整合的目的。模型內含兩個主要部份。一是三維供應鏈規劃網路暨資訊傳遞模型((簡稱三維立體模型),另一個是適用於晶圓代工業的核心供應鏈規劃模型(簡稱規劃引擎)。 三維立體模型,它整合供應鏈內垂直與水平方向的參與者,同時也將時間軸上不同時程規劃(長、中、短期)一起併入模式考量範圍。根據公司參與的製造步驟,三維立體模型亦可彈性地由基本型擴充為擴張型。不論是基本型或是擴張型,各節點根據座標軸(coordinate)定義功能並提供服務,這種設計可以提高模式穩健度,減低因外界的變化而引發系統變更需求。系統也可以由座標幫助輕易找到可以提供服務的節點與資訊傳遞的控制(資訊傳遞規則),資訊可以有序的傳遞分享。 在核心規劃引擎部份,針對晶圓代工產業在長、中、短期規劃需求,以及產業長生產前置時間時間的特性,設計隨時間變化參數適用於長、中期的線性規劃 (Linear Programming, LP) 模型與適用於短期規劃的啟發式 (heursitic ) 演算模型,配合三維立體模型所定義結構與資料傳遞規則,各時程(長、中、短期)製造階段節點皆可獲取必要資料並進一步以適當規劃法則求取同步與整合的規劃結果。 最後利用物件導向分析 (object-oriented analysis) 中順序圖 (sequence diagram)、狀態圖(state diagram)、與類別圖 (class diagram) 展示三維立體模型的系統應用架構(application framework)。 關鍵字:供應鏈規劃,規劃整合,資訊傳遞,線性規劃,物件導向分析,應用架構
62

會計基礎評價模型之實證研究--考慮線性資訊動態 / An Empirical Study of the Accounting Based Valuation-- With Linear Information Dynamics

洪佩嫆, Hong, peiyung Unknown Date (has links)
本研究以Ohlson (1995) model為發展基礎,並將盈餘定義為(1)剩餘淨利及(2)盈餘水準,分別就此二種不同定義下的盈餘,以年度盈餘時間序列來測試其是否符合線性資訊動態假設,及針對各模式對股權價值估計與預測之結果做比較,探討何種評價方法或模式對於估計真實價值、解釋價格及預測報酬之效果較佳。 研究結果發現,我國上市公司之剩餘淨利及盈餘水準時間序列皆符合線性資訊動態假說。剩餘淨利線性資訊動態模型較能正確預估次一期的盈餘。相較於單獨以帳面價值來估計股價,考慮線性資訊動態模型所建立之各評價模型所預測之估計股價皆未能正確預測權益價值及解釋權益價值之波動。在投資策略方面,因剩餘淨利模型之投資績效最為穩定,在該模型之投資策略下,V/P比率愈低(高)之投資組合獲得之平均股票報酬愈低(高),代表股價愈是被低估的投資組合可賺取更多之投資報酬,這說明剩餘淨利模型預測次期投資報酬之能力最佳,投資人可以其做為建立投資策略的參考。 / Based on Ohlson (1995) model, this study specifies earnings variables as both residual income and earnings levels to test the linear information dynamic (LID) models per se and the ability of competing valuation models to value the contemporaneous stock prices. A comparison of future stock return predicting capability of competing models is also conducted. By using both residual income time series and earnings levels time series for examining the issue on the firms listed on the Taiwan Stock Exchange (TSE), the empirical results support Ohlson’s information dynamics. However, when estimated as a time series, the linear information models using either residual income or earnings levels variables provide value estimates no better than book value does alone. From the investment strategy aspect, the superior predictive ability of the residual income valuation model with respect to future stock returns demonstrates that high (low) V/P ratios gets high (low) investment returns. It implies that the underpriced portfolio makes high investment returns. Accordingly, the residual income valuation is good for estimating returns on the following year and is therefore a valuable investment reference..
63

多層線性模型的分層樣本數組合問題:對跨國政治文化研究的啟示

呂宜勵 Unknown Date (has links)
政治學者近年來已將多層線性模型當作研究政治文化的重要工具,不但應用在既有的資料庫分析上,同時也希望在資料蒐集過程中將所需要的資料特性納入抽樣設計裏,以期能克服目前此法在應用上所面臨的問題。在眾多問題中,最重要的莫過於是「總樣本數一定下個體和總體層次樣本數組合如何影響推論可靠性的問題」,學界對此過往是採取「30/30原則」,也就是個體和總體層次的樣本數都至少要在30個以上推論才會比較穩定,但近來許多研究顯示,如果將個體層次的樣本數縮減到15個而極大化總體層次樣本數,所得出的推論會比「30/30原則」來得更穩定,因此許多學者紛紛倡議應採用新發現而捨棄「30/30原則」。本文針對這樣的提議,利用教育學及政治學二領域資料,從模型意含的討論,進而使用模擬方法來測試這樣的提議是否站得住腳。 本文發現「極大化總體層次樣本數」原則並不能當作普遍認知,因為過往的所有文獻皆對單一母體資料進行剖析,尚未察覺母體資料型態影響參數表現的可能性,然而,本研究變化不同資料特性進行模擬結果顯示,母體資料結構確實會造成不同的參數表現,以致最適樣本組合也跟著不同。另外,我們觀察到固定效果和隨機效果的最適樣本配置偏重於不同層次的樣本數目,固定參數、固定效果以總體層次為主,但隨機參數、隨機效果、迴歸參數等卻不能忽視個體層次樣本個數,所以研究者都應該認真思考其在意的參數為何,才能針對所關切的現象本身設計出最適樣本配置,而做出實質且有效的討論。
64

應用賽局理論評價選擇權

陳韻竹 Unknown Date (has links)
本論文利用市場觀測的選擇權買價與賣價,將市場的交易行為描述為兩人零合賽局,其中參賽者為投資人與市場機制,分別建立雙方的最佳策略模型。假設標的資產到期日的價格為離散點且個數有限,當市場不存在套利機會,也就是投資人最佳策略時報償為零時,可利用賽局線性規劃模型導出隱含於市場價格的風險中立機率測度。此模型不須對標的資產價格的機率分配做任何假設,也不須計算波動度,就可利用資產價格的平賭性質,以還原的風險中立機率測度為選擇權作合理的定價。最後,以台指選擇權(TXO)為例,驗證本模型的評價能力,且再次證實資產價格的風險中立機率分佈與一般常假設的對數常態分佈有落差。
65

夏季缺電之產業最適限電策略模擬研究 / A Simulation Study on Optimal Strategies of Industrial Electricity Rationing for Coping with Power Shortage in Summer

洪敏睿, Hung, Min Jui Unknown Date (has links)
台灣夏季高溫酷熱使得各產業夏月用電量較全年月平均高出5%~24%。台電公司發電機組的備轉容量率在過去幾年的夏季也多次逼近限電警戒值(6%)。在未來氣候變遷趨勢下,夏季極端高溫發生機率提高,發電容量因受環保及社會因素影響難以同步擴充,限電極可能成為台灣在夏季必須面對的挑戰。本文旨在建構一描繪台灣經濟體內所有生產及消費部門相互依賴連結的線性規劃產業關聯分析(linear programming input-output analysis,簡稱LPIO)模型,用以求解經濟成長過程中若遇夏季供電瓶頸時之可行產業最適用電配置(限電)策略——限制用電之產業組合及配比。 根據現實情況所需以決定策略,首先策略的考量為追求經濟成長,加上當前台灣為一加工出口國,應將主要出口品之部門列為供電瓶頸的考量之一。接著,評估所有產業之間的相關性,單一產業的成長可帶動其他產業的發展;反之,單一產業的損失影響亦會衝擊其他產業,因此需要了解產業間的投入產出關係才能制定對我們經濟最有效率的資源配置策略。本研究首創以「夏季模擬產業關聯表」來校準LPIO 模型之模擬,切合實際地反映產業的季節性投入需求,以提升總體多部門模型之應用分析在政策制定參考上的實用性。 結果顯示若出口部門之VAEE能得到提升,則可以於供電瓶頸時期既維持出口市場的成長,GDP的成長亦不需要犧牲,因此出口部門應該以其在國際市場所占有的優勢,回饋於國內生產技術,降低其產品內含電力之使用,則可於供電瓶頸時減少對經濟體中其他部門的限電壓力。然而,出口部門其勞動投入佔原始投入的比重較小,因此當優先出口發展的同時亦應該考慮的國內勞動力的問題。各產業之間勞動份額的改變程度大小,以培養未來可得到良好發展之產業所需的勞動力投入。
66

小波理論於曲風辨識上之應用 / The Application of Wavelet Transform on Automatically Musical Genre Classification

陳彥名 Unknown Date (has links)
隨著科技的進步,網際網路已充斥在我們的生活之中。音樂也不再以硬體儲存的方式流傳(例如CD、黑膠唱片),而是轉變為數位音樂的方式,透由網路平台散播。許多數位音樂串流服務平台網站也如雨後春筍般誕生,例如iTunes、Spotify、Musicovery。加上文化水平的提升,音樂已是現代人生活之中,不可或缺的一部分。世界上的音樂難以計數,如何將音樂分門別類做好管理乃為現代商業應用的一個重要課題。因此,音樂曲風自動化辨識的技術確實為一個實用且難以迴避的課題。 過去在曲風自動化辨識已有許多研究,但內容不外乎音訊處理、頻譜轉換、特徵擷取、特徵降維、監督式學習機。在相同的模式下提出各種改良,或是全新的特徵擷取…諸如此類,而辨識率也達到了七成以上。本篇論文採用不同於以往的做法,將訊號進行頻譜轉換後層層降維,所得之訊號搭配LDA與決策樹進行辨識,最後去比較與分析離散餘弦轉換與小波轉換在辨識率上的優劣。我們發現搭配小波轉換與混合LDA及決策樹的方法,可以將音樂曲風之分辨率達到八成五以上。
67

猝睡症患者疾病嚴重度、神經認知功能對生活品質關聯之縱貫研究:階層線性模型分析 / The Relationship between Symptom severity, Neuro-Cogntive Function and Quality of Life on Narcolepsy: A Hierarchical Linear Model study

王志寰, Wang, Chih Huan Unknown Date (has links)
本研究旨在探討猝睡症患者生活品質受症狀變化及神經認知功能改變的影響情況,以及不同層次影響因素對患者生活品質的初始狀態及後續變化軌跡的影響效果。 本研究於北部一所醫學中心睡眠障礙科及兒童心智科募集確診為猝睡症之患者,經同意後進行為期五年的長期研究,募集總人數168人,完成五年資料收集人數85人。本研究使用睡眠多項檢驗(polysomnography, PSG)、多段入睡測試(multiple sleep latency test, MSLT)、人類白血球抗原檢驗(human leukocyte antigen, HLA)為基本檢驗工具,以電腦化第二版康氏持續注意力測驗(Continuous Performance Test- II)及威斯康辛卡片分類測驗(Wisconsin Card Sorting Test, WCST)為檢測神經認知功能之工具,以自填艾普渥斯嗜睡程度量表(Epworth sleepiness scale, ESS)、史丹佛睡眠問卷(Stanford sleep inventory, SSI)及簡式生活品質量表(short from-36 items of health related quality of life, SF-36)做為症狀嚴重度及生活品質的依據。資料分析以描述統計及階層線性模式(hierarchical linear models , HLM)統計方法進行。主要結果如下: 一、 猝睡症患者生活品質分為生理與心理兩個層面,患者生理層面在五年期間維持相對穩定沒有顯著變化;心理層面中之不同向度則有不同變化趨勢,心理健康與活力向度隨時間有逐漸提高的趨勢,患者此二向度生活品質接受治療後有穩定上升的趨勢,而社會功能及情緒角色限制則呈現二次方曲線變化,以及呈現先增後減的發展軌跡,患者此二向度接受治療後顯著上升,第三年後有逐年下降的趨勢。 二、 患者嗜睡程度及猝倒嚴重度變化隨時間有顯著成長軌跡,呈二次方曲線發展,轉折點在第三年,接受治療前三年症狀呈現穩定降低的軌跡,但自第三年起逐年增加,此結果與藥物治療初期症狀獲得顯著改善,後期改善幅度相對減少,及藥物效果具有關聯。 三、 個體間層次變項僅疾病持續時間、HLA對患者生活品質具顯著解釋力,其中疾病持續時間越長,患者可能發展因應症狀之策略,從而降低疾病對生活品質之衝擊。而HLA則對症狀有不同影響,HLA陽性患者初始嗜睡程度較陰性者為低,且接受治療後改善效果較陰性者顯著,猝倒嚴重度起始值較陰性者高,且接受治療後的趕善幅度較陰性者小。 四、 疾病嚴重度變化對生活品質具顯著影響,完整模式分析中,時間主效應未達顯著,但可由症狀變化及神經認知功能改變進行更佳的解釋。嗜睡程度變化僅對身體疼痛向度變化不具有解釋力外,對其餘七個向度均具顯著影響;猝倒影響層面不及嗜睡程度,但亦可解釋生理量表、生理角色限制、心理量表、心理健康、情緒角色限制、活力等向度上的變化。 五、 神經認知功能改變與否對患者生活品質具有加成效果,分析顯示患者神經認知功能改善時,其生活品質提升速率較未改善者高,影響較顯著的包括注意力、警覺度及概念反應,此結果與下視丘泌素參與的維持注意力及前額葉功能有關。 本研究依據分析結果提出猝睡症患者生活品質受嗜睡症狀及猝倒嚴重度改變直接影響,同時受人類白血球抗原屬性及神經認知功能改變調節之假設模型,作為未來研究參考依據。並根據研究結果與限制,提出對臨床實務的應用與心理介入的建議,並對未來提升猝睡症患者生活品質相關研究提供建議。 / The current study aims to: (1) examine the change of eight domains of quality of life in narcoleptics within five years, (2) investigate the impact of the change of symptom severity on different dimension of quality of life, as well as the influence associated with the change of neuro-cognitive function. There were 168 participants recruited from a medical center in northern Taiwan. 85 of them completed the 5-year annual follow-up data collection. During the follow-ups, polysomnography (PSG), multiple sleep latency test (MSLT) and human leukocyte antigen (HLA) test were conducted. Computerized neuropsychological tests of Conners’ Continuous Performance Test- II (CPT-II) and Wisconsin Card Sorting Test (WCST) were also administered to obtain attention and executive function data. The short from-36 items of health related quality of life (SF-36), Stanford sleep inventory (SSI) and Epworth sleepiness scale were applied to assess quality of life and symptom severity. Descriptive statistics and hierarchical linear models were applied for data analysis. The main results were: 1. The quality of life was divided into physical and psychological domains. The physical domain kept relatively stable during the 5-year follow up as opposed to the psychological domain. In psychological domain, the vitality and psychological health showed increasing tendency overtime. However, the social function and role functioning-emotion increased during the first 3 years then declined afterward. 2. The symptom severity also showed a tendency corresponded to quadratic curve. The daytime sleepiness together with cataplexy severity reduced immediately after treatment but rose after the third year. 3. The variables of individual characteristics that showed significant impact on quality of life were disease duration and HLA type. The longer the duration, the better quality of life one had. Positive HLA typing seemed to be a protective factor on severity of sleepiness. It also predicted better treatment outcomes, but worsen the severity of cataplexy and treatment effects. 4. The symptom severity could be a good explanation as a variable of quality of life. The daytime sleepiness altered all domain of SF-36 expect body pain. Cataplexy affected only psychological domain of SF-36. 5. The neuro-cognitive function was also found to affect quality of life. Those who improved in attention and executive function test got greater improvement on SF-36 as well. The vigilance on CPT-II and conceptualized response on WCST had most significant impact. I proposed a model of change of quality of life in patients with narcolepsy based on the results obtained. Several suggestions were also proposed for clinical and psychological intervention for narcolepsy to improve their quality of life.
68

台灣跨族群工具性交友網絡研究 / The research of cross-ethnic friendship and instrumental network in Taiwan

唐經硯 Unknown Date (has links)
在本論文中,研究者認為影響受訪者跨族群交友的主要因素主要可從兩方面來看,分別為兩者連繫的同質性、連繫強度、接觸場合、社經地位差序變項,以及受訪者個人的世代、族群、教育程度與跨族群交友偏向程度。透過1997年三期三次「台灣地區社會變遷調查」社會網絡與社區組調查資料,本論文使用階層線性模型(Hierarchical Linear Models,HLM),從受訪者與他人的兩者關係所形成的連繫層次,以及受訪者個人層次來對台灣跨族群交往的現象作進一步的分析。研究結果發現,受訪者個人特質,例如受訪者教育程度、所屬族群,較兩者連繫特質,例如兩者連繫強度、認識場合,更強烈地影響了跨族群連繫形成的可能性,這樣的結果在過去由於方法上的限制,無法得到驗證,透過此研究,可對台灣族群相關網絡研究在建立跨族群連繫的可能因素上,提供了不一樣的看法與解釋。 / In this paper, I argued that what impacts the respondents constructing the cross-ethnicity ties can be treated from two perspectives. One is the tie-level, such as the homogeneity, tie strength, contact contexts, and socio-economical resources variables between two actors. The other is the individual-level, like the generations, ethnicities, levels of education, and the degrees of the preference for making cross-ethnic ties of the egos, that is, the respondents. I tested my hypotheses using the social network data in 1997, called Taiwan Social Change Survey (TSCS). Through building the hierarchical linear models, some advanced analysis could be done for understanding the cross-ethnic interaction phenomenon in Taiwan by considering the tie-level and the individual-level at the same time. The research results showed that when talking about the possibility of making cross-ethnic ties, personal characteristics, like levels of education, and ethnicities, are more important than tie characteristics, such as tie strength and meeting places of the two. However, this outcome cannot be examined in the past because of the methodological restrictions. Through this research, it provides different sights and explanations for discussing the possible reasons for constructing cross-ethnic ties in the social network researching area in Taiwan.
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超越指數績效的投資組合最佳化模型 / Portfolio optimization models for enhanced index investment

朱志達, Chu, Chih Ta Unknown Date (has links)
建立指數基金時,通常是利用追蹤指數的技巧,選取少量的股票建構指數基金使得報酬率與標的指數(benchmark index)報酬率同步的投資組合。如果能建立包含少量股票的投資組合,就可達到指數追蹤的效果,那麼也能利用少量的股票建立績效可以超越指數基金的投資組合。本論文利用建構指數基金的方法以及大中取小的概念,挑選出一個績效可以超越標的指數的投資組合。本論文提出的模型亦考慮實務上交易所需的各項成本、整數交易單位與資產總類數等限制。因此,模型包含整數變數與二元變數。最後以台灣加權股價指數的相關資料做為實證研究的對象,實證結果顯示本論文提出的模型所建立的投資組合超越標的指數的績效平均年化報酬率25%。 / Setting up an index fund usually uses techniques of index-tracking that choosing few stocks forming a portfolio to obtain the same return rate as the benchmark index. Similarly we can use the same concept to set up a portfolio such that the performance is better than index’s. In this thesis we use index-tracking methods and minimax rule to obtain a portfolio which outperforms the benchmark index. In the proposed mathematical model we will consider the transaction costs, integer trading unit volume, and the total number of assets in the portfolio. Therefore the resulting model is a mixed integer nonlinear programming including integer variables and binary variables. Finally, the empirical study will be performed by using the data from the Taiwan stock market to verify the performance of our model. The empirical study shows that the portfolios created by our models outperform the benchmark index up to 25% in average.
70

核能電廠大修排程的最優化

張維仁 Unknown Date (has links)
隨著經濟的高度成長及電廠興建的日益困難,電力的需求問題是愈來愈嚴重。如何有效率地安排核能機組進行例行性的停機大修及燃料再裝填工作是重要的課題。本論文中考慮核能發電機組五年時程的大修排程問題,我們將這個大修排程問題描繪成一個大型混合型整數線性規劃模型。由於問題的龐大與複雜,此問題的最佳解難以求出。因此,我們發展數個邏輯條件式有效地縮小解集合空間;另外並發展出一個啟發性演算法,採用合併變數法將0/1決策變數合併,使原問題轉成較小的合併模型。先解合併後的合併模型,利用合併模型答案的資訊來固定原始模型的部分變數值之後,再解原始問題。幾個實例計算顯示此演算法的可行性。 / Since the growth of economics and the difficulty to build a new power plant, the supply of electric power has become very tight. It is important to ensure the efficient operation of nuclear power plants, including timely shutdown, refueling and maintenance schedule. In this thesis, we deal with the scheduling shutdown and maintenance of nuclear power plants for a five-year time period. This problem can be formulated as a large-scale mixed integer linear problem. The difficulty of solving this problem is due to the large number of binary variables. We then develop several valid logical constraints to reduce the complexity in processing using the branch and bound technique. Also, a heuristic based on the aggregation and dis-aggregation techniques has been developed to yield a good solution. Several examples are given to show the applicability of the algorithm.

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