本論文著眼於All-IP網路中的預算分配。我們定義網路的服務品質只與各使用者使用網路頻寬的要求有關，提出一種使管理者能以統計上百分比來估計網路服務品質的方法。這個方法包含路徑選擇以及頻寬分配二個階段。為了展現這種方法的可行性，我們列舉一些數據來分別比較以最大滿意度和最小成本為目標的不同分配結果，作為使用這個方法的參考。 / In this thesis, we focus on budget allocation for All-IP networks. We propose a method which assists managers to estimate the quality of service on networks. The quality of service on networks is defined by satisfaction functions that are simply written in terms of bandwidth required by the users on the network. We present a two-phase approach which includes a path se-lection and a scheme for bandwidth allocation. In order to illustrate an easy implementation of this approach, we also develop the Maximum Satisfaction Method and the Minimum Cost Method. Numerical examples are given to show the effectiveness of our approach.

近十年來，由於無線網路的普及與人們對於即時服務的需求提高，導致人們迫切需要更好的服務品質，WiMAX是其中最被看好的一種無線網路傳輸技術。但在WiMAX無線網路中，標準的規格中並未規範connection admission control (CAC)、bandwidth request (BR)、bandwidth allocation、scheduling等機制，在本篇論文中，我們將上述機制設計並實作於MAC layer中。 本論文首先探討在設計connection admission control、bandwidth request、bandwidth allocation、scheduling會遇到的相關參數及相關議題。並進一步提出一個有效的方法以改善目前大部分設計在bandwidth allocation的公平性 (Fairness)及contention bandwidth request等效率差的問題。我們將設計一個MAC Layer co-function，稱之為Dynamic Polling Interval function (DPI function)。利用DPI function設計no contention bandwidth request改善傳統 contention bandwidth request的效率，以及利用DPI function的特性改善bandwidth allocation以及scheduling的公平性。最後我們將利用網路模擬器NS-2 (Network Simulater version 2)與測試實驗架構作不同效能的驗證比較並評估所提方法的有效性。 / Over the past decade, wireless network access and real-time services have become more popular than ever. People are eager to have better quality of service. Among all, WiMAX is one of the best wireless communication technigues . However, WiMAX standard does not specify those mechanisms of connection admision control (CAC)、bandwidth request (BR)、bandwidth allocation and scheduling . In this thesis, we propose the above mechanisms and imcorporate them as MAC layer functions. First, we discuss those related parameters and issues when designing connection admision control、bandwidth request、bandwidth allocation and scheduling. Second, we propose an efficient method to improve the fairness of bandwidth allocation and efficiency of contention bandwidth request. We design a MAC layer co-function called dynamic polling interval function (DPI function). We use the DPI function to design a no contention bandwidth request method to improve the efficiency of traditional bandwidth request method and use the features of DPI function to improve the fairness of bandwidth allocation and scheduling. At last , we use NS-2 (Network Simulator version 2) as our network simulator and compare the result of simulations to prove the efficiency of our proposed methods.

京都大学 / 0048 / 新制・課程博士 / 博士(教育学) / 甲第21409号 / 教博第229号 / 京都大学大学院教育学研究科教育科学専攻 / (主査)教授 明和 政子, 准教授 森口 佑介, 教授 楠見 孝 / 学位規則第4条第1項該当 / Doctor of Philosophy (Education) / Kyoto University / DGAM

組織績效是企業生存之保證, 同時也可作為社會資源分配之參考。由以往組織績效評 估之研究可發現, 有關這方面之研究, 遭遇到之最大難題乃是缺乏一套普偏性之評估 標準。 本論文主要研究制造業及服務業之高階層管理人員與內部稽核人員, 對於三個有關評 估組織績效之因素重要性之看法。在本研究中, 此三個主要因素為:(1)組織目標,(2) 數量化評估工具,(3)非數量化評估工具。 本研究之主要目的為:(1)研究四組樣本對組織績效評估工具之重要性之看法,(2)研究 四組樣本間及各組樣本中, 對組織績效評估工具之選擇是否有重大差異。由此而有四 個假設:(1)四個樣本間之看法是否有重大差異?(2)以組織規模之大小而言, 各組樣本 中之看法是否有重大差異?(3)內部稽核人員是否會因服務年數之不同而有不同之看法 ?(4)內部稽核人員是否會因有無會計師事務所之經驗而有不同之看法? 本研究之樣本分為制造業及服務業, 各抽取一百七十家企業, 每家企業再分為高階層 管理人員及內部稽核人員, 亦即嚴格來說有四組樣本。每個受試者被要求對於評估組 織績效之每一主要因素排列其重要性。資料分析所使用之統計方法為多變項變異數分 析及皮爾森積差相關分析。 本研究最后再就統計分析所獲得之發現, 提出結論及建議, 作為往后對組織績效評估 之研究和作業審計研究之參考。

我們以公平頻寬配置考慮網路上多重等級與多重服務品質的效用函數， 利用權重效用函數提出兩種數學最佳化模型。 這兩個模型的目標都是要尋找權重效用函數總和值的最大值。 本篇論文特別以權重為決策變數， 研究最佳權重的行為模式， 並求得最佳權重分佈公式。 我們發現模型I的總權重效用只看重某個效用值最大的等級， 完全忽略其他效用值較小的等級； 即最大效用函數的最佳權重為1，其他效用較小的最佳權重為0。 在最佳化過程中， 模型II的數值資料呈現出最佳權重架構為：最佳權重中的每個權重均相等，且總和為1。 我們隨後證明這些結果，並利用GAMS軟體來呈現數值資料。 / We propose two mathematical models with weighted utility functions for the fair bandwidth allocation and QoS routing in communication networks which offer multiple services for several classes of users. The formulation and numerical experiments are carried out in a general utility-maximizing framework. In this work, instead of being fixed, the weight for each utility function is taken as a free variable. The objective of this thesis is to find the structure of optimal weights that maximize the weighted sum of utilities of the bandwidth allocation for each class. We solve it by proposing two models in terms of fairness. Model I and II are constructed to compare different choices for optimal weights. For Model I, the structure of optimal weights form a vector which consists of one for a class and zero otherwise. For Model II, the form of optimal weights is that each weight of utility function is equally assigned. The results are proved and illustrated by software GAMS numerically.

本文主要解釋農村基礎教育為何長期受制於經費不足的制約，在有限的教育資源下，偏遠地區農村學校又何以出現校際差異與教育資源分配的不均等。透過回顧中國農村基礎教育發展的歷史過程，本文認為1950年代以來分權化的教育財政制度，使農村中小學不僅仰賴地方政府財政撥款，更強調學校自身資源汲取能力的重要性。但在基層財政能力有限的情況下，導致偏遠農村基礎教育長期陷於經費不足的困境，也使農村學校呈現階層化發展。 在教育經費財政撥款不足的情況下，學校資源汲取能力成為教育發展的關鍵，而決定學校資源汲取能力很重要的因素，在於學校所處教育層級的位置。層級化的農村教育體系，將學校之間劃分成上下不同層級，處於最高層級的示範學校比層級最低的村小，具有更強的資源汲取能力，造成有限的教育資源呈現階層化流動。晚近在學生人數減少的衝擊下，由於學生人數多寡直接影響學校規模大小，決定資源汲取能力並影響學校存廢，更形強化層級化的教育體系。 目前中國推行的改革措施，若無法徹底改變由地方負責農村基礎教育經費的財政制度，便無法打破既存的層級化教育體系，促進教育資源分配的均等。無足夠經費的教育改革措施，將阻礙農村基礎教育改革，最終導致農村中小學的兩極分化，產生資源相對集中的示範學校與資源相對匱乏的普通學校。

本論文針對隨機數位網路提出一套可行的計算機制，以提供網路管理者進行資源分配與壅塞管理的分析工具。我們研究兩種利潤最佳化模型，探討在預算控制下的頻寬分配方式。因為資源有限，網路管理者無法隨時提供足夠頻寬以滿足隨機的網路需求，而量測網路連結成功與否的阻塞機率(Blocking Probability)為評估此風險之一種指標。我們利用頻寬分配、網路需求量和虛擬端對端路徑的數量等變數，推導阻塞機率函數，並證明阻塞機率的單調性(Monotonicity)和凸性(Convexity)等數學性質。在不失一般性之假設下，我們驗證阻塞機率是(1)隨頻寬增加而變小；(2)在特定的頻寬分配區間內呈凸性；(3)隨網路需求量增加而變大；(4)隨虛擬路徑的數量增加而變小。 本研究探討頻寬分配與阻塞機率之關係，藉由推導單調性和凸性等性質，提供此兩種利潤模型解的最適條件與求解演算法。同時，我們引用經濟學的彈性概念，提出三種模型參數對阻塞機率變化量的彈性定義，並分別進行頻寬分配、網路需求量和虛擬路徑數量對邊際利潤函數的敏感度分析。當網路上的虛擬路徑數量非常大時，阻塞機率的計算將變得複雜難解，因此我們利用高負荷極限理論(Heavy-Traffic Limit Theorem)提供阻塞機率的估計式，並分析其漸近行為(Asymptotic Behavior)。本論文的主要貢獻是分析頻寬分配與阻塞機率之間的關係及其數學性質。網路管理者可應用本研究提出的分析工具，在總預算限制下規劃寬頻網路的資源分配，並根據阻塞機率進行網路參數的調控。 / This thesis considers the problem of bandwidth allocation on communication networks with multiple traffic classes, where bandwidth is determined under the budget constraint. Due to the limited budget, there exists a risk that the network service providers can not assert a 100% guaranteed availability for the stochastic traffic demand at all times. We derive the blocking probabilities of connections as a function of bandwidth, traffic demand and the available number of virtual end-to-end paths for all service classes. Under general assumptions, we prove that the blocking probability is directionally (i) decreasing in bandwidth, (ii) convex in bandwidth for specific regions, (iii) increasing in traffic demand, and (iv) decreasing in the number of virtual paths. We also demonstrate the monotone and convex relations among those model parameters and the expected path occupancy. As the number of virtual paths is huge, we derive a heavy-traffic queueing model, and provide a diffusion approximation and its asymptotic analysis for the blocking probability, where the traffic intensity increases to one from below. Taking the blocking probability into account, two revenue management schemes are introduced to allocate bandwidth under budget control. The revenue/profit functions are studied in this thesis through the monotonicity and convexity of the blocking probability and expected path occupancy. Optimality conditions are derived to obtain an optimal bandwidth allocation for two revenue management schemes, and a solution algorithm is developed to allocate limited budget among competing traffic classes. In addition, we present three elasticities of the blocking probability to study the effect of changing model parameters on the average revenue in analysis of economic models. The sensitivity analysis and economic elasticity notions are proposed to investigate the marginal revenue for a given traffic class by changing bandwidth, traffic demand and the number of virtual paths, respectively. The main contribution of the present work is to prove the relationship between the blocking probability and allocated bandwidth under the budget constraint. Those results are also verified with numerical examples interpreting the blocking probability, utilization level, average revenue, etc. The relationship between blocking probability and bandwidth allocation can be applied in the design and provision of broadband communication networks by optimally choosing model parameters under budget control for sharing bandwidth in terms of blocking/congestion costs.