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資產模型建構與其資產配置之應用 / Asset Modeling with Non-Gaussian Innovation and Applications to Asset Allocation陳炫羽, Chen, Hsuan Yu Unknown Date (has links)
因為股票市場常具有厚尾、偏態和峰態的特性且在國際的股票市場之間,股票報酬長存在有尾端相依的情況,所以我們的資產模型不能選用Gaussian分配。
近幾年來,常用GH 分配建構單維度的股票報酬。這篇文章將利用多元仿射JD、多元仿射VG 和多元仿射NIG分配去建構風險性資產的報酬並請應用到資產配置。
建構風險性資產的報酬後,我們提供兩種不同形式的投資組合並且可以導出投資組合的期望值、變異數、偏態和峰態。我們嘗試以投資組合的期望值、變異數、偏態和峰態當成我們的目標函數,然後得出未來最佳的投資組合的權重。為了讓我們的資產配置更加動態和有效率,我們重新估計模型的參數、選擇最佳的投資組合權重,然後重新評估最佳的資產配置在每個決策日期。實證結果發現當股票市場的表現好的時候,我們建議資產配置應使用偏態當成我們的目標函數,但是當股票市場的表現太好的時候,我們建議資產配置應使用變異數當成我們的目標函數。 / Since the stock markets always have the characteristics of heavy-tailness, skewness and kurtosis and there exists tail dependence among the international stock markets, we can’t use the Gaussian distribution as our model. Recently, the generalized hyperbolic (GH) distribution has been suggested to fit the single stock returns. This article will use the multivariate affine JD (MAJD), multivariate affine variance gamma (MAVG) and multivariate affine normal inverse Gaussian (MANIG) distributions to construct the risky asset returns, and apply them to asset allocation.
After constructing the risky asset returns, we provide two different forms of portfolio and obtain the mean, variance, skewness, kurtosis of portfolio. We can try to select the optimal weights of portfolio by using the mean, variance, skewness, kurtosis of portfolios as our objective functions. To make our asset allocation more dynamic and efficient, we re-estimate all parameters for our models, select the optimal weights of portfolio, and re-assess the optimal asset allocation at each decision date. Empirically, when the performances of stock markets are good, we suggest that our asset allocation uses the skewness as the objective function. When the performances of stock markets are not good, we suggest that our asset allocation uses the variance as the objective function.
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單元製造系統之人力配置策略研究 / A Study of Operator A ssignments Flexibility within and betwe en Cellular Manufacturing Systems張毓欣 Unknown Date (has links)
由於少量多樣的生產趨勢,單元製造系統(Cellular Manufacturing Systems)已成為目前製造業的重點之一。在單元製造系統中,具有多種技能的員工是必備的條件,如何有效的配置人力策略即為本研究的重點。人力配置策略包含了指定式(由單一操作員負責某件工作)、共享式(由兩名或兩名以上操作員共同負責某件工作)及混合式人力配置策略(同時使用指定式和共享式兩種策略),其中,共享式和混合式的人力配置策略可稱為彈性人力配置策略。要使用彈性人力配置策略,需要有人力彈性(Labor Flexibility)。
所謂的人力彈性在單元製造系統可分為兩個方向:(1)單元間的人力彈性(Inter-Cell Labor Flexibility),即不同單元間的轉換能力,(2)單元內的人力彈性(Intra-Cell Labor Flexibility),即單元內不同工作間的轉換能力。本研究分為兩個主要部份,分別探討在單元間採用彈性人力配置策略和在單元內採用彈性人力配置策略對於工作量平衡程度、工作量共享程度和績效表現的影響。
根據研究結果,在單元內採用彈性的人力配置策略對於操作員間的工作量平衡和績效表現皆有直接且正向影響,但隨著操作員數目的減少,彈性的人力配置策略對於績效表現之影響減弱、甚至變為負向效果;在單元間採用彈性的人力配置策略之效果和在單元內採用彈性的人力配置策略相似,對操作員間的工作量平衡和績效表現亦有直接且正向影響,且隨著單元數增加,在單元間採用彈性的人力配置策略對績效表現的影響增強。本研究之結果可做為運用彈性的人力配置策略以及規劃交互訓練時的參考方向,並可用此架構來預測績效改變。 / The object of the research is to study agile labor assignments in cellular manufacturing systems by intra-cell and inter-cell operator’s mobility. There are three labor assignments strategies including dedicated (only one operator is responsible for a work), shared (two or more than two operators are responsible for a work), and combined assignment (using both of dedicated assignment and shared assignment). Different assignments lead to different workload balancing, workload sharing and performance.
The research builds a simulate framework which includes operators’ moving rule, proposition of empirical study and index of workload balancing and workload sharing. According the result of research, applying intra-cell operator’s mobility can improve operator’s workload balancing and performance. Nevertheless, the relationship of intra-cell operator’s mobility and performance would decrease with decreasing of labor limited. The impact of inter-cell operator’s mobility is similar to intra-cell operator’s mobility, but it would increase with increase of complexity. The simulate framework which pass through the testing can use in an actual company case, provide a direction of how to use labor assignments, and forecast the impact of using agile labor assignment.
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勞退保證投資收益率制度及制度轉換選擇權之研究 / The Selection of Rate of Return Guarantee and the Choice between Defined Contribution and Defined Benefit for Labor Pension Plan in Taiwan李翎竹, Lee, Ling-Chu Unknown Date (has links)
我國勞工退休金新制自2005年7月1日開始實施,由過去的確定給付制改為具有確定提撥特色的「個人帳戶制」。對於勞工而言,確定提撥制和過去確定給付制不同之處在於承擔退休金投資風險的責任將由雇主轉由個人承擔。如何透過退休機制的設計以降低退休金的投資風險是近年來的重要議題,因此本文主要從個人偏好與風險的觀點探討保證投資收益率制度與制度轉換選擇權等兩個降低確定提撥制投資風險的重要配套措施。
在本論文的第一篇研究中發現,資產配置與國際投資對保證成本的影響頗大,在個人可選擇資產配置的情況下,高投資風險的資產選擇將造成政府未來龐大的或有負債。為了解決政府保證成本過高造成代內與代間的財富移轉,本文從使用者付費與個人效用的觀點探討保證投資收益率制度的設計,發現藉由設立保證投資收益上限可提升風險趨避者、損失趨避者與後悔趨避者等偏好下的預期效用,且能降低個人管理下方風險所需的提撥成本與退休計畫參加者所需繳交的保證費用,故建議政府可將投資收益率上限納入保證投資收益率制度,供退休計畫參加者選擇合於本身偏好的保證收益率上限。
在近來許多國家的公、民營退休體系由過去以確定給付制改為確定提撥制,為了降低在確定提撥制下的退休金投資風險,在美國的佛羅里達州之公務人員退休體系中,存在著可供個人選擇是否轉換到確定給付制的機制。在我國勞退新制中除了從過去的確定給付制改為確定提撥制外,亦輔以「年金保險制」供勞工選擇與轉換,若年金保險制具有確定給付制的特徵,則勞工等於是擁有一個從確定提撥轉換轉到確定給付制的選擇權,因此制度選擇權的探討對我國而言亦是相當地重要。在本論文的第二篇研究中發現,當風險趨避程度越高則轉換至確定給付制的機率越高,轉換到確定給付制的高峰期會出現在開始工作的初期與屆臨退休之際等兩段期間。隨著工作期間的延長,個人轉換到確定給付制的機率越低,但仍可有效地提升退休金的所得替代率與達到降低退休金下方風險的效果,在加入退休制度初期不得轉換的限制之後,會降低轉換到確定給付制的機率。 / The Labor Retirement Pension Act enacted in 2005 introduced defined contribution (DC) pension plan for substituting the traditional defined benefit (DB) pension plan. In the defined contribution pension plan, the investment risk is transferred to the participants. However, the design of rate of return guarantee makes the investment risk less severe for participants. In the first essay, we find that the asset allocation and foreign investment have large impact on the guarantee cost: the high risky investment may result in large potential liability of the government in the future if participants have the investment portfolio choice. This study develops a framework to analyze design of rate of return guarantee from the financial engineering and user paid principle view. We find that the cap of investment return guarantee not only increases the expected utility of risk aversion, loss aversion and regret aversion, but also decreases the contribution cost to participant associated with managing the downside risk.
Around the world, the defined contribution (DC) plans have been the primary trend of pension reform in the both public and private sector. In an attempt to decrease the investment risk associated with DC plan, the public employees are provided with an option to buy back DB plan in the Florida State of U.S.A. In the second essay, we find that the higher level of risk aversion is, the higher probability to buy back DB plan is. During the employee’s early years of service and as the employees near retirement, the probability to exercise the option is the highest. The probability to exercise the option is decreasing with the years of service being increasing; the option also increase the pension replacement rate as well as decrease the downside risk of pension. The probability to exercise the option is lower, when the option to buy back the DB plan is prohibited during the employee’s early years of service.
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公有閒置設施活化利用為銀髮福利設施之研究 ─以臺北市為例 / A Study of Government Owned Idle Facilities Activate To Pension Facilities In Taipei City張哲瑋, Chang, Che Wei Unknown Date (has links)
臺北都市公有空間由於缺乏供給與需求配置的妥善評估,產生許多設施與建築發生閒置與低度利用的情況,造成環境的負擔以及資源的不平均分配。同時,臺北市持續面臨高齡化社會現象,銀髮福利設施是政府未來發展項目重點之一,現行多數研究先少探究銀髮福利設施於區域之設置標準。本研究針對公有閒置設施活化利用為銀髮福利設施,透過國內外文獻回顧,歸納「安全性」、「規模性」、「參與性」為銀髮福利設施主要活化原則,並建立分析模型。接著援用各級政府閒置設施資料庫,並結合社經資料,應用GIS系統進行閒置設施供給與銀髮福利設施需求的配置分析。透過分析模型與多評準決策分析法,篩選與評估不同地區與空間適合發展銀髮福利設施配置,藉此研擬相關活化策略。
實證結果顯示臺北市市中心位置對於銀髮福利設施之需求為高,相對其缺乏資源,以萬華區、文山區、松山區為嚴重。各公有閒置設施受到內在外在條件之影響,各閒置設施發展強度不同,結果顯示鄰里型服務範圍較適合發展安養護機構、社區型服務範圍較適合發展日間照顧中心、地區型服務範圍較適合發展安養護與日間照顧混合型設施。最後依據各別公有閒置設施之配置結果,建議未來公有閒置設施活化為銀髮福利設施之策略,配合設施內在外在條件,如人口、政策、文化、區位等等,使閒置設施達到最大活化效益。 / In Taipei City, there are government owned urban facilities and buildings which become idle facilities and with low utilization due to the lack of proper evaluation of supply and demand. It causes uneven distribution of resources to environment. Meanwhile, Taipei city faces the issue of aging society. The Government has to develop pension facilities for future planning. There are few existing studies discussed about the configuration standard of pension facilities. Therefore, this study explores the planning principles of pension facilities included safety, scale of facilities, participation, and the activating operations of public idle spaces by using the social-economic and idle spaces data of the Government. Also, this study simulates supply and demand data with GIS system. We analyze and evaluate the allocations which suitable for developing pension facilities in different regions and spatial conditions through Allocation Simulation, multiple criteria decision. Thus, it can be a reference for activating idle spaces for Taipei city.
The results of supply and demand simulation show that the demand for pension facilities is higher in the center of Taipei City that lack of resources, including Wanhua District, Wenshan District and Songshan District. Each government owned urban facilities may be affected by outer and inner conditions which cause different development intensity. The results show that neighbor-type facilities are suitable for developing retirement centers, community-type facilities are suitable for developing day care centers, region-type facilities are suitable for developing mix-used centers. Finally, according to all allocation results, it is recommended strategies should be added with outer and inner conditions which including population, policy, culture, location and allocation, in order to maximize the usage efficiency of idle facilities.
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國民小學教師教學型態與普通教室空間規畫之研究張美玲, Chang, Mei-Lin Unknown Date (has links)
本研究的主要目的,在調查臺北縣市國小普通教室空間規畫之現況以及近十年內之趨勢,瞭解臺北縣市國小教師教學型態運用情形並探討其與教室空間規畫的關係、調查教師認為其教學所需之普通教室空間形式與附屬教學設備為何、進而提出對普通教室教學空間規畫的建議,俾作為未來普通教室空間規畫之參考。
本研究選取臺北縣、市各38所學校為研究對象,每所學校各抽取12位(偏遠學校為6位)班級的導師共864位為研究對象(有效樣本526人,包含臺北縣233人、臺北市293人),進行問卷調查,並以次數百分比統計和卡方考驗進行分析,從研究結果發現中我們得到以下的結論:
壹、臺北縣市國小普通教室空間規畫之現況
一、近十年來之學校空間設計朝多元化、彈性化之開放空間的趨勢發展
1.教室平形狀擺脫標準之「傳統長方形平面」的窠臼
2.教室空間形式之設計趨向多邊形、開放、彈性之原則
3.教室走廊空間形式由單邊走廊之單一形式轉變為雙邊走廊之多用途形式
4.舊校設備比新校設備的數量多
二、班級座位安排法的多元化與校舍新舊、教室空間形式、課桌形式以及教師教學型態等因素的差異性達顯著
三、學習角落的設置需要空間,並和教師教學型態有關
貳、臺北縣市國小教師之教學型態及其與教學空間規畫之關係
一、教師教學型態多元化程度與普通教室空間形式、教室附屬教學設備多寡等教室空間設計因素的差異性達顯著
二、教師教學型態多元化程度與教室課桌形式、班級座位安排法以及學習角落設置個數等教室空間配置等因素的差異性達顯著
參、教學革新趨勢下教師理想中之普通教室空間規畫
一、絕大多數教師心目中的理想教室空間為彈性、開放、多元化的空間
二、有七成的教師認為理想的座位安排方式為小組式座位安排法,而有六成教師認為理想的課桌椅形式為長方形單人課桌
三、有五成以上教師認為最需要的附屬教學設備以科技化教學設備為主,也有五成以上教師認為最需要設置的學習角落為語文圖書角、電腦角與遊戲角。
研究者根據文獻探討與研究發現,提出下列幾點建議:
一、普通教室平面形狀方面,應配合班級人數來設計長短邊之比例
二、普通教室空間形式方面,應以開放、彈性、多元化為原則
三、普通教室走廊空間的設計應以具多用途功能之空間為原則
四、普通教室附屬教學設備應增加科技化教學設備的設置
五、革新課桌椅形式,以利教師依教學需求變化班級座位安排
六、教師應依學生學習之需求彈性地調整教室空間的配置,並提昇使用教學設備的能力
七、未來研究可以進一步地針對不同教室空間的個案進行深入的觀察與訪談,來探討其對教師教學的影響
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數位網路上多重目標規劃的數學模式 / Mathematical Models of Pareto Optimal Path Selection on All-IP Networks王嘉宏, Wang, Chia-Hung Unknown Date (has links)
面對通訊與資訊科技的大幅進步,通訊網路正在進行一個巨大的變革,要將電信網路與數據網路整合成一個單一的All-IP網路以支援所有網路應用服務。欲達到整合型網路的理想,仍有許多困難尚待克服,而服務品質問題是其中最關鍵的問題之一。因為受限於封包交換網路之原有的特性,All-IP網路有影響服務品質的三項因素:過長的延遲時間、抖動以及封包遺失。首先,我們利用了達成度函數(achievement function)來處理單位的轉換,使得能夠同時考量此三項不同單位的因素。接著,本文中提出一套方法來解決All-IP網路上端對端(end-to-end)的資源配置及路徑規劃問題。在分配資源時,我們企圖提供一種成比例的公平性給各個不同等級。此公平性的精神是要使得所有網路使用者的滿足程度相當,而非各個不同等級的使用者分配到相同的資源。我們將以預算方式控制端對端品質管理以追求使用者之整體最大滿意程度。
本論文的規劃概念是將網路規劃分成兩個階段。第一階段是在一筆給定的總預算底下,以成比例的方式去分配資源給各個不同等級,並建置網路上的頻寬,使各等級能依其需求拿到適當的頻寬,確保滿足程度相當。
接下來第二階段則是在第一部份已完成的規劃基礎下,做路徑規劃,指派新進入的使用者到一條較好的路徑,在滿足此使用者的延遲時間要求下,使此系統的壅塞程度越小越好。路徑規劃的概念為如何挑選最佳網路路徑,以規劃具服務品質之端對端路徑,並可達到資源之最有效利用。網路營運者將可運用此套方法來調校自身所營運的網路以追求使用者最高滿意度。 / We present an approach for the fair resource allocation problem
and QoS routing in All-IP networks that offer multiple services to users. The objective of the optimization problem is to determine the amount of required bandwidth for each link and each class to maximize the sum of the users' utility. In this work, we focus on approaches that, while allocating bandwidth, attempt to provide a proportionally fair treatment of all the competing classes. First, we will show that an achievement function can map different criteria subject to various utility onto a normalized scale. It may be interpreted as a measure of QoS (Quality of Service) on All-IP networks. Using the bandwidth allocation model, we can find a Pareto optimal allocation of bandwidth on the network under a limited available budget. This allocation can provide the so-called proportional fairness to every class, that is, this allocation can provide the similar satisfaction to each user. Next, we present a routing scheme under consideration of the delay. Such an optimal path provides the end-to-end QoS guarantees to each user. Finally, a numerical example is given to illustrate how to solve the fair resource allocation problem and how to modify the nonlinear parts.
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