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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.
1

排程的隨機動態規劃模型及其在管理上的應用

黃欣伸, HUANG, XIN-SHEN Unknown Date (has links)
本論文共壹一冊,約四萬五千字,分七章。 提要: 考慮一工作站中有一組工作(Ji, i =1……N)需經由一部機器完成之排程問題。 假設每一工作Ji有已知之到期日Di,其過期之違約金計算可為任意函數,且由於技術 或工作性質等因素而使得工作之進行有一定之順序限制。對此模型最佳解之求得可結 合二元結構表示法及動態規劃法找出使總違約金為最少之工作順序。本文假設工作J 之完成日Ci,違約金Pi,而過期之違約金計算函數為Pi、MAX {Ci-Di0},而探討 如何結合二元結構表示法及動態規劃法,以較節省之電腦空間求得最佳解,及在允許 改變工作間飲優先順序後,如何迅速求得新解。此外將模型一般化,允許工作之完成 時間為多變量常態分配之隨機變數,並求得最佳解。
2

在虛擬環境中以攝影學法則開發智慧型攝影機模組 / Designing an Intelligent Camera Module with Cinematography in Virtual Environment

鄭仲強, Cheng,Chung-Chiang Unknown Date (has links)
本研究在虛擬環境中發展出一套符合攝影學法則的即時智慧型攝影機模組,當使用者操縱化身時能夠給予攝影機自動規劃之能力,不需要花費額外的心力控制攝影機。智慧型攝影機的能力包含了規劃不被障礙物遮蔽的跟蹤拍攝,以及當攝影機進入險惡的環境時,自動在兩台攝影機之間進行符合攝影學法則的轉切。此外,此智慧型攝影機模組能夠依照不同使用者的偏好,產生不同結果的攝影機規劃。我們實作了此一智慧型攝影機的系統,並以實例說明此系統的有效性。 / We have developed a real-time intelligent camera module with a set of cinematography in a virtual environment. Its automatic camera planning capacity allows that the users to spend less effort in controlling the camera when manipulating an avatar. An intelligent camera should be able to plan unobstractive tracking motion and necessary cuts automatically between two cameras with the rule of cinematography. In addition, the results of the camera planning can be customized by setting appropriate parameters in accordance with the user’s preferences. We have implemented this intelligent camera system, and demonstrated the effectiveness of this system through several examples
3

退休基金之策略性資產配置 / Asset allocation of optimal strategy in pension management

楊凱勛 Unknown Date (has links)
本研究討論以負債導向之退休基金的資產配置模型,並以股票型風險性資產為主要配置標的。隨機控制模型在推導過程中相當繁瑣,經常得不到封閉解,本研究之優點為,實際導出多項資產標的下之一般化封閉解,可進行財務經濟推論,直接得到不同參數對基金之影響,輔以台灣公務人員退撫基金第4次精算報告,為實證研究對象,接著加入投資限制之情境分析與模擬,得到結論。最適提撥隨著正常成本及給付上升而提高,若退休基金於當期有殘餘基金,則可因由投資獲利而少提撥部分資金。回饋函數之最適解同時權衡反應未來之精算正常成本與當期給付,正常成本上升而增加風險性投資,而因當期給付上升而減少風險投資趨於保守。若股票市場報酬率大於利率,投資者將增加股票之比例,以增加投資效果,投資者將對市場股票型資產同時做多空操作,進行避險。反之,隨著短期利率上升後,投資於股票部位將會漸漸移入現金持有,減少股票型風險性資產佔總資產之比例。
4

最適資產配置-動態規劃問題之數值解 / Optimal asset allocation-the numerical solution of dynamic programming

黃迪揚, Huang, Di Yang Unknown Date (has links)
動態規劃是一種專門用來解決最適化的數學方法,其觀念源自於Bellman (1962),他提出了動態規劃的最佳原則,然而動態規劃問題不見得有封閉解(closed form solution),即使其存在,求解過程往往也相當困難且複雜。Vigna & Haberman (2001)用動態規劃方式找出最佳的投資策略並分析確定提撥制(defined contribution)下的財務風險;本研究擬以Vigna & Haberman (2001)的模型為基礎,提出解決動態規劃問題的數值方法。 Vigna & Haberman (2001)推導出確定提撥退休金制度下離散時間的最適投資策略封閉解,透過該模型,我們可以比較本研究所建議的方法與真正封閉解的差異,證實本研究所建議的方法的確可以提供動態規劃問題一個接近且有效率的數值解法。接著根據Yvonne C.(2002、2003)的抽樣方法,希望在進行模擬時,能找出模擬情境的特性並對這些情境進行抽樣,藉此減少情境數以增加電腦運算的效率。最後應用在Vigna & Haberman (2001)的修正模型以及Haberman & Vigna (2002)的模型上,說明了本研究所建議的數值方法也適用在各類型的動態規劃上,包含理論封閉解不存在以及求解非常複雜的問題。
5

微分賽局在行銷通路之應用─合作廣告

余俊慶, Yu, Chung-Ching Unknown Date (has links)
在經濟活動發展迅速的情形下,產品的競爭與多樣化使得廠商在價格之外,也須將行銷策略納入考量。研究行銷通路中成員互動的理論模型從靜態模型開始,到用動態微分賽局的模型來研究廠商間的互動,過去的研究文獻得到了兩點結論:第一,通路合作為Pareto最適。第二,在通路無法合作的情況下,利用合作機制的建立,能使均衡結果產生Pareto改善。 然而,過去的文獻卻未說明將通路合作放入合作廣告的模型中,通路合作是否仍為Pareto最適。因此,本研究沿用Jørgensen et al.(2003)合作廣告模型的設定,將通路合作的情況放入模型中,比較通路合作、零售商遠視、零售商短視與合作廣告四種情形均衡時的行銷策略及廠商的利潤,並探討通路合作在合作廣告的模型中是否仍為Pareto最適。
6

WCDMA系統中配置OVSF碼滿足服務品質之研究 / OVSF Code Assignment Based QoS in WCDMA

林淑瑩 Unknown Date (has links)
WCDMA是一個寬頻直接序列分碼多工存取(DS-CDMA)系統,使用正交可變展頻係數(Orthogonal Variable Spreading Factor,OVSF)碼以支援多樣化的資料傳輸速率,提供可變動位元速率和服務品質(Quality of Service,QoS)保障,以滿足使用者對多媒體應用服務的需求。在本研究中我們將訊務分群並配置符合的正交變數展頻係數碼的方式,來處理資源分配的問題,期讓每位使用者都能有滿意的服務品質。在論文中,為提供不同等級的差別服務以兼顧QoS和避免頻寬浪費,我們提出以動態群組配置的方式,從所有提出服務要求的訊務中,依其服務優先等級順序,挑選適合的訊務,將其放置於同一群組。系統會配置一OVSF碼給此群組,透過分時共用來進行資料傳輸,使其能提供多樣化的資料傳輸速率,減少碼阻斷,提高系統頻寬的使用率,並滿足使用者對服務品質的需求。實驗模擬顯示,本研究所提出的方法能提供多樣化的資料傳輸速率,並能有效減少碼阻斷,提高頻寬及系統使用率,並達到QoS的要求。 / WCDMA is a wideband Direct-Sequence Code Division Multiple Access (DS-CDMA) system, it uses Orthogonal Variable Spreading Factor (OVSF) codes to support diverse data transmission rates. Orthogonal variable spreading factor codes have the ability to provide variable bit rates and QoS to meet different multimedia application requirements. In this research, we group the traffic and use Orthogonal Variable Spreading Factor (OVSF) technique to deal with resource allocation problem in order to offer satisfactory quality of service to the users. We propose dynamic group allocation method to provide differentiated services in order to meet the QoS requirement and avoid bandwidth wasting. From all those requested services, we move all those services of the same service priority to the same group. The system will subsequently assign OVSF code to each group. Data transmission of each group is based on time-sharing mechanism. Simulations show that the proposed method can provide diverse data transmission rates, and is able to reduce code blocking rate, increase bandwidth and system utilization, and meet the QoS requirement.
7

數學規劃在叢聚分析上的應用研究

江振東, JIANG, ZHEN-DONG Unknown Date (has links)
通常,在我們所取得的任意一組資料裡,由於內在特性的關係,往往會使資料自然形 成若干叢聚(Clusters)。叢聚分析(Cluster Analysis)的目的,就是如何藉由數 量的方法,找出這些自然形成的叢聚,俾便於往後資料的整理和分析。儘管界定叢聚 的角度,將因人、因事而有所不同。然而根本上,這就是一個尋找最佳解的方法,來 找出資料中的最理想分組,便成為一種自然而可行的嘗試。本文係就動態規劃、整數 規劃(整數規劃模式改以Subgradient Method求解)、暨分支定限法(Brandhand-bo und Method)如何處理叢聚分析問題,分別予以討論比較。
8

設備更新及其計劃之實例研究

陳清文, Chen, Qing-Wen Unknown Date (has links)
一、研究動機:設備更新是經常面臨的問題。設備更新分析已發展出多種模式,可是 廠商未能充分使用,乃引發本研究對其中問題再做探討。 二、研究架構:(一)列舉設備更新面臨的問題。(二)探討各種模式是否解決前項問題 并做小幅度修正。(三)比較與選用模式。 三、研究重點:(一)綜合整理各種更新模式并比較應用。(二)時間幅度及不確定性對 各種模式及決策的影響。(三)設備更新計劃之擬定。(四)實證研究。 四、研究方法:(一)由文獻收集各種更新模式。(二)應用動態規劃法、隨機法、模擬 法等新式方法。(三)各種模式做敏感度分析,以供決策參考。
9

考量保險業加入國外投資之最適組合 / Incorporating Foreign Equities in Optimal Portfolio Selection for Insurers and Investors with Significant Background Risks

洪莉娟, Li-Chuan Hung Unknown Date (has links)
本研究探討面臨顯著背景風險(諸如核保等風險)金融機構之投資策略,考量加入國外投資風險下,該金融機構如何決定最適動態資產配置策略,為充分反映市場風險、匯率風險及核保風險,本研究以隨機方程式描述資產價值及核保經驗之變動,並以假想之人壽保險公司作為討論對象,預估未來現金流量並建構公司財務資訊相關之隨機模型,給定最低資本限制下,於指定投資期限內達到全期淨值(盈餘)最佳效用值為目標。本文依照給定之背景風險建構隨機控制模型,利用動態規劃法求出最適資產配置。結果顯示最適投資組合將由三項要素組成:1.極小化盈餘變化之變異數之部位;2.類似於短期投資組合策略之避險部位;以及3.用以規避背景風險之避險部位。因為模型複雜性之限制,以逼近馬可夫理論之數值方法計算最適投資策略。 / This paper analyzes the optimal asset allocation for insurers and investors who are required to cope with significant background risks due to underwriting uncertainties and interest rate risks among a set of stochastic investment opportunities. In order to hedge properly the country risks due to local volatile financial market, the foreign investment opportunities are included in the optimal portfolio decision. In this study, detailed formulation using the projected cash flows of a hypothetical life insurance company and its related stochastic phenomena are constructed. The insurers are assumed to maximize the expected discounted utility of their surplus over the investment horizon under the minimal capital requirement. Our problem is formulated as a stochastic control framework. According to the optimal solution, the optimal portfolio can be characterized by three components: a hedging component minimizing the variance of the change in surplus, a hedging component familiar to myopic portfolio rule, and a risk hedging component against the background risks. Since the explicit solutions cannot be achieved due to model complexity, the Markov chain approximation methods are employed to obtain the optimal control solutions in our numerical illustration.
10

計算幾何學在選區劃分上之分析與應用 / Electoral Redistricting using Computational Geometry

謝長紘, Hsieh, Chang Hung Unknown Date (has links)
選舉是實行民主政治最有效的方法之一,而選區劃分的方式將直接或間接的影響投票結果與民主政治理念的施行。 然而在選舉法規或行政區域發生變動時,舊有的選區劃分方式需要隨之調整。而傳統人工的方式具有許多缺點,如:耗費人力資源、人口分配不均、難以兼顧形狀及行政區完整等等。若每次行政區域發生變動,都需要重新劃分,將花費許多不必要的人力、物力及時間,因此利用電腦以完成自動劃分的技術逐漸受到重視。 本論文中我們打破現有的政治與人文鴻溝,嘗試以系統化的方法對選區劃分作全面性的查驗。我們利用計算幾何學的特性與人工智慧搜尋的技巧,儘量找出可能的劃分方式再進行評估。我們依據中選會的建議採用村裡為劃分之最小行政區域,從數以十萬計之合理解中,根據形狀等客觀條件篩選出較佳之劃分方式,進而將歷史投票行為加入考量,以對篩選出的劃分方式作進一步評估與分析。 實作中我們以台南市為對象,在不同的人口限制及形狀條件下,分別比較所能找到的合理解數目。同時選出一部分的劃分方式,和中選會的劃分方式比較,結果顯示我們的方法可以全面性的分析選區劃分,不同的劃分方式可能產生不同的選舉結果。 / Election is one of the most effective way of conducting democratic politics, and mean of electoral redistricting shall post effect, either directly or indirectly, on electoral outcome as well as delivering ideas of democratic politics. As election regulations or administrational districts experience alterations, the present electoral districting is forcefully accompanied with adjustments. Electoral redistricting using traditional human labor works reveal several flaws such as: human resource wastage, uneven population distributions, hard to maintain shape contiguity and compactness, as well as the completeness of administration districts. Every single alteration experience in administration district requires redistribution, thus expensing on unnecessary human labor, resources and time. As such, it had brought great attention on techniques of automatic redistribution by means of modern computer technologies. In this thesis, we shall breakthrough a giant gap between politics and humanity; conduct a thorough examination on systematic approach on electoral redistricting. We are going to utilize characteristics of computational geometry and artificial intelligence searching techniques to find out every conceivable means of redistricting then evaluation the performance of them. By recommendation of Central Election Commission (hence CEM), we will adopt the classification of township as basic unit of administrational district, from counts of thousand adequate explanations, by objective factors of shape accordance and others, select the better means of redistricting methods, and afterward put into concern of historical voting behavior, conduct a further evaluation and analysis upon chosen redistricting method. In actual practices we had selected Tainan City as the experiment target, under different population limitations and factors of form, compare the searchable numbers of decent explanation respectively. We choose some redistricting outcomes, and put into comparison with redistricting method of the CEM. The results indicated our approach is able to conduct a thorough redistricting analysis, as well as more diversified comparing to CEM's outcome. The result of this experiment also reveals different election outcome with adoption of different redistricting methods.

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