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收集所有交通大學研究人員與學生個人或團體所發表之各項學術著作，涵蓋期刊論文、教師專書、學位論文等項。;;Collections of Publications of NCTU Researchers and Students Like Journal Papers and Thesis.

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🏛️國立陽明交通大學機構典藏

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廣義的機會式通訊---無線行動網路中之競爭、合作與感知---子計畫二：感知無線行動網路之協力式跨層設計
(2009)
李大嵩
;
LEE TA-SUNG
;
國立交通大學電信工程學系(所)
在無線網路中協力式通訊是一種利用分散的空間資源的重要技術，然而，節點間的合作關係及各節點在網路中的位置造成協力通訊系統在設計上的困難。而在有限的傳送能量限制下，如何有效率的利用能量在訊源端與中繼端之間傳送訊號是一個非常重要的議題，因此在設計任何可以提升網路服務品質的技術時，亦都必須考慮網路的分散特性。另一方面，為了能夠有效率的使用網路資源，能夠自我重置（Reconfigurable）的感知式（Cognitive）網路功能（例如軟體無線電）亦逐漸變成一種典型的策略。本子計畫目標在設計各種能應付協力式網路特有問題的軟體無線電解決方案，於計畫第一年中，吾人將從跨層設計的角度建立能有效利用能量的節點對節點傳輸策略，其結合了節點選擇與最小化路由能量的功能。於第二年中，吾人將著重於分散式前置編碼（Precoding）法則之設計，此舉除了可避免共通道的節點互相干擾外，亦可同時獲得訊號多樣（Diversity）增益。最後，於第三年中吾人將針對資源分配最佳化之議題（如在通道已知的條件下進行頻譜與能量分配）進行研析，以大福提昇全網路之服務品質。所有在本子計畫所提出之方法皆能依網路環境（如通道狀況或鏈結通道之訊雜比）適應性地進行調整，因此能自然地使用軟體無線電實現，使得吾人所提出的方法能更適用於未來的無線通訊網路。
以運輸多樣性觀點建立都市永續運輸評估與資源分派模式
(2009)
馮正民
;
FENG CHENG-MIN
;
國立交通大學交通運輸研究所
交通運輸系統中，多元化的用路人會依需求的不同，而對交通設施與運輸服務產生不同的需要，然而，因應不同需求的目標常常是相互衝突的。運輸多樣性（diversity）的基本定義即為不同權益關係人（stakeholders）需要（needs）被滿足的程度。過去關於永續運輸（sustainable transport）之研究，多著重於經濟、社會及環境觀點，但缺乏永續運輸與權益關係人需求之關聯分析。永續運輸指標研究中，多探討指標的代表性，但對影響永續運輸指標的因果關係（causal effect）分析較為不足。此外，運輸規劃者進行資源配置（resource allocation）時，尚無系統化的評估決策模式可應用，導致無法決定運輸建設資源配置的優先順序，而無法達成永續運輸之目的。有鑑於此，本研究根據永續運輸及多樣性相關文獻，以歸納問題特性並探究關鍵之指標與架構。繼而，研擬同時滿足運輸權益關係人不同需求之多樣性，及符合永續發展之指標群，並探討該指標群與永續運輸間之相關性。此外，本研究將建立具因果架構（Causal framework）之永續運輸系統，以利公部門評估如何有效配置運輸建設資源、有系統地提升運輸多樣性與永續性。最後，將研擬都市永續運輸之規劃模式，以求解並驗證都市永續運輸評量系統之可操作性，藉由情境分析評估公共建設資源之配置對於都市永續運輸及多樣性之績效。
電視頻帶白空間之寬頻行動雲端感知無線網路
(2010)
王協源
;
Wang Shie-Yuan
;
國立交通大學資訊工程學系（所）
Resource Allocation in Cognitive Radio Relay Networks
(2013-03-01)
Liang, Jui-Chi
;
Chen, Jyh-Cheng
;
交大名義發表
;
資訊工程學系
;
National Chiao Tung University
Cognitive radio has received great attention recently for its ability to improve spectrum efficiency by letting secondary users to access spectrum resource that is unoccupied by primary users. However, cognitive radio also brings new challenges in the design of future wireless networks. In this paper, we investigate the problem of resource allocation in cognitive radio networks. Specifically, we consider the problem of proportional fair scheduling in cognitive radio relay networks. Our problem formulation takes into account the fluctuations of usable spectrum resource, channel quality variations caused by frequency selectivity, and interference caused by different transmit power levels. We prove that the problem is NP-hard and is computationally infeasible to be solved in a timely manner by using brute force algorithms. An easy-to-compute upper bound for the formulated problem is also derived. We then propose two heuristic algorithms that are easy-to-implement, yet achieve performance close to the upper bound. The proposed algorithms can be executed and finished within 1 millisecond. Thus, they can meet the requirement of real-time scheduling. Simulation experiments verify that the proposed algorithms can achieve good proportional fairness among users and enhance system throughput by proper power control.
Optimal Resource Allocation for Increasing Strictly Concave Utility Functions in Wireless Networks
(2012-03-01)
Lee, Tsern-Huei
;
Huang, Yu-Wen
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Chen, Chien-Nan
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傳播研究所
;
Institute of Communication Studies
Utility functions are widely used to model user-perceived service quality. For elastic traffic, the utility function is often concave. An elastic allocation (EA) algorithm has recently been proposed to maximize the total utility obtained by users, assuming resource is infinitesimally divisible and queues are constantly backlogged. We found that the EA algorithm is not always optimal. In fact, the solution it obtains can be infeasible. In this paper, we present a modified EA algorithm that is guaranteed to find the optimal solution under the same assumptions. The result is generalized for a system where queues are generally backlogged. In a real system, there is normally a basic unit for resources. Therefore, we further extend the designs to such a system for both constantly backlogged and generally backlogged queues. To reduce computational complexity, we also propose suboptimal resource allocation algorithms. Simulations are conducted to evaluate the proposed algorithms in terms of utility sum and execution time. Results show that our proposed algorithms perform better than previous works. Moreover, the performances of the proposed suboptimal algorithms are close to those of the optimal algorithms.
Motivation and resource-allocation for strategic alliances through the DeNovo perspective
(2005-03-01)
Huang, JJ
;
Tzeng, GH
;
Ong, CS
;
運輸與物流管理系註：原交通所+運管所
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科技管理研究所
In recent years, there have been proposed many theories and models, such as transaction cost theory and the resource-based view, to explain the formation of strategic alliances. However, the perspectives are usually limited and incomplete. Additionally, the problem of resource allocation is also a serious issue when firms enter strategic alliances. This paper proposes a holistic perspective and provides an optimal resource portfolio by using the DeNovo perspective. A numerical example demonstrates the criteria of strategic alliances and provides the optimal resource portfolio. (c) 2005 Elsevier Ltd. All rights reserved.
Interference analysis and resource allocation for TDD-CDMA systems to support asymmetric services by using directional antennas
(2005-05-01)
Wang, LC
;
Huang, SY
;
Tseng, YC
;
資訊工程學系
;
電信工程研究所
This paper explores the advantages of using directional antennas in time division duplex (TDD) code division multiple access (CDMA) systems to support asymmetric traffic services. In the TDD-CDMA system, the transmission for asymmetric traffic from neighboring cells may cause the cross-slot interference, which can seriously degrade system capacity. To avoid the cross-slot interference for TDD-CDMA systems, many current resource allocation algorithms typically require a global control on the transmission direction (either downlink or uplink) in each time slot. Apparently, this requirement substantially constrains the flexibility of TDD-CDMA systems to deliver asymmetric traffic services in a more practical situation where every cell may have different uplink and downlink bandwidth requirements. We analyze the interference of the TDD-CDMA system with a trisector cellular architecture, where three directional antennas are employed at each base station. We find that the directivity of directional antennas can provide an additional degree of freedom for allocating radio resource. Taking advantage of this property, we introduce the concept of virtual cell, defined as the same converge area of a cell but is composed of three sectors from the three adjacent base stations. Furthermore, we propose a new virtual cell-based distributed code/time slot allocation algorithm to enable a TDD-CDMA system to provide asymmetric services with different rates of asymmetry in every cell coverage area. We demonstrate that the proposed algorithm does not only offer more flexibility in handling nonuniform traffic patterns, but maintain good radio link performance and call blocking performance.
A novel dynamic resource allocation model for demand-responsive city logistics distribution operations
(2006-11-01)
Sheu, Jiuh-Biing
;
運輸與物流管理系註：原交通所+運管所
;
Department of Transportation and Logistics Management
This paper presents a dynamic customer group-based logistics resource allocation methodology for the use of demand-responsive city logistics distribution operations. The proposed methodology is developed based on the following five developmental procedures, including: (1) specification of demand attributes, (2) customer grouping, (3) customer group ranking, (4) container assignment, and (5) vehicle assignment. The numerical results show that the model permits managing both the time-varying customer order data and logistics resources dynamically with the goal of optimal logistics resource allocation. Particularly, both the aggregate operational costs and average lead time are reduced by 27.4% and 8.7%, respectively, in a case study. (c) 2005 Elsevier Ltd. All rights reserved.
Resource allocation in network processors for network intrusion prevention systems
(2007-07-01)
Lin, Yi-Neng
;
Chang, Yao-Chung
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Lin, Ying-Dar
;
Lai, Yuan-Chen
;
資訊工程學系
Networking applications with high memory access overhead gradually exploit network processors that feature multiple hardware multithreaded processor cores along with a versatile memory hierarchy. Given rich hardware resources, however, the performance depends on whether those resources are properly allocated. In this work, we develop an NIPS (Network Intrusion Prevention System) edge gateway over the Intel IXP2400 by characterizing/mapping the processing stages onto hardware components. The impact and strategy of resource allocation are also investigated through internal and external benchmarks. Important conclusions include: (1) the system throughput is influenced mostly by the total number of threads, namely I x J, where I and J represent the numbers of processors and threads per processor, respectively, as long as the processors are not fully utilized, (2) given an application, algorithm and hardware specification, an appropriate (1, J) for packet inspection can be derived and (3) the effectiveness of multiple memory banks for tackling the SRAM bottleneck is affected considerably by the algorithms adopted. (C) 2007 Elsevier Inc. All rights reserved.
Adaptive subcarrier assignment and bit allocation for multiuser OFDM system using ordinal optimization approach
(2008-09-01)
Lin, Shin-Yeu
;
Huang, Jung-Shou
;
電控工程研究所
;
Institute of Electrical and Control Engineering
In this paper, we propose an ordinal optimization (OO) theory-based four-stage approach to deal with the subcarrier assignment and bit allocation problem of a multiuser orthogonal frequency-division multiplexing (OFDM) system. The four-stage OO approach ensures the quality of the obtained solution, however, at the cost of solving a continuous version of the considered problem in the first stage. To resolve this computational complexity problem, we propose a hardware-implementable dual projected gradient (DPG) method to exploit deep-submicrometer technology. Compared to some existing methods using numerous simulation cases with randomly generated parameters, our approach is excellent in the aspect of power consumption. In the meantime, the estimated computation time of our approach can meet the real-time application requirement. Furthermore, we use extensive simulations to compare our good-enough solutions with the true optimal solutions, and the results show that the objective value obtained by our approach deviates from the optimal objective value around 1% on average.

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🏛️國立陽明交通大學機構典藏

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