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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.
431

Strata, Structure, and Strategy for Resource Allocation and New Product Development Portfolio Management

Chao, Raul O. 09 July 2007 (has links)
Innovation and new product development (NPD) are critical to firm success and are often cited as means to a sustained competitive advantage. Unfortunately, the question of which innovation programs to pursue and how they should be funded is not trivial. This thesis examines the resource allocation and NPD portfolio problem. Special emphasis is placed on the organizational and behavioral factors that influence this problem. In doing so, we adopt a hierarchical perspective and posit that the resource allocation and NPD portfolio problem acquires a unique structure depending on the level at which the problem is considered. Beginning at the firm level, each study attempts to break open a black box to understand the drivers of effective resource allocation and NPD portfolio decisions at successively more detailed levels of analysis. We begin with an analysis of the firm's total R&D investment and we show how R&D intensity (the percentage of revenue that is reinvested in R&D) depends on a combination of NPD portfolio metrics and operational variables. We then extend the analysis to reveal how a simple evolutionary process explains the often cited consistency in R&D intensity at the industry level. Next, we analyze how the R&D investment is partitioned into "strategic buckets" consisting of NPD programs that are characterized by type of innovative activity (incremental or radical). We show how time commitment, technological/market complexity, and potential disruptions to the technology/market environment influence the balance between incremental and radical programs in the NPD portfolio. Finally, we analyze how individual NPD programs are funded and how they evolve over time in an organization setting that is defined by more or less autonomy. We find that how best to allocate resources depends on two types of autonomy bestowed upon managers: autonomy with respect to NPD funding and autonomy regarding how the NPD budget is monitored and controlled. We conclude with a discussion of the theoretical and managerial implications of our work.
432

Power Allocation Scheme in Multi-Hop MIMO Amplify-and-Forward Relay Networks

Chen, Jing-Yu 11 July 2011 (has links)
With perfect channel state information at all the transmission terminals, the asymptotic capacity of multi-hop multiple-input multiple-output(MIMO) amplify-andforward(AF) relay channels is derived. Although the derivation is based on the assumption of a large number of antennas, simulation results show that the derived expression is surprisingly accurate for even a small number of antennas, and may even be superior to existing results. In addition, based on the asymptotic result, we present different power allocation schemes to (i) minimization the transmit power; (ii) maximization the network throughput; (iii) minimization the transmit power over all source. Fortunately, the proposed power allocation problems can be formulated using geometric programming(GP). Therefore, the optimal power distribution among the multi-hop relay can be obtained efficiently. For multiuser scenarios, since it is possible that the QoS of each user cannot be satisfied simultaneously, we study jointly admission control and power allocation optimization problem. This joint problem is NP-hard. Therefor, we propose an iterative algorithm to reduced the complexity.
433

Efficient Bandwidth Allocation with QoS support for IEEE 802.16 Systems

Lai, Da-Nung 07 September 2011 (has links)
Multimedia applications in wireless communication have shown notable increases over recent years. Specifically, Quality of Service (QoS) has become an important support mechanism in the context of a variety of applications which utilize network resources. The IEEE 802.16 standard for Wireless Metropolitan Area Networks (WirelessMAN) provides a complete QoS control structure designed to enable flow isolation and service differentiation over the common wireless interface. Although the media access control (MAC) mechanisms defined in this standard can offer predefined QoS provisioning on a pre-connection basis (additionally, many algorithms have been addressed to support QoS guarantees for various kinds of applications), the design for a stable, efficient and flexible MAC scheduling algorithm for such QoS provisioning still remains to be discovered. In this paper, we propose a QoS control scheme, Efficient Bandwidth Allocation (EBA), for the WirelessMAN system. Notably, this schedule enables predefined service parameters to control the service provided for each uplink connection and it provides each connection with different service opportunities such that the BS could allocate the most suitable bandwidth constantly for each connection with the various QoS parameters. Moreover, through MAC layer resource allocation, the proposed algorithm is capable of providing QoS guarantee for the SSs under different distance.
434

Efficient Memory Allocation for User and Library Variables in Recursive Programs with WCET/ACET Tunable Performance

Fang, Hsin-Jan 09 February 2012 (has links)
Scratchpad Memory (SPM) is an alternative to cache. With SPM, the CPU¡¦s fast internal memory (ie, the SRAM) is directly mapped into the memory address space. This has the advantages of reduced power (by avoiding the memory management Unit, MMU, that a cache need to manage its tags and evictions), reduced area (for the same reason), and predictability.[1] Predictability is important in real-time systems, because each task must be assigned a deadline. If a task finishes early, there is no benefit. But if a task finishes late, then the effect is undesirable or even catastrophic. This means that the worst-case execution time (WCET) is more important than average-case execution time (ACET). The disadvantage of SPM, when compared to cache, is that the SPM requires software management of the fast memory. In a previous student¡¦s work from our laboratory, [3], an SPM allocator was presented for WCET-targeted compilation. Compared to that work, this current thesis make four key contributions. First, it introduces a significant amount of code infrastructure to allow library variables to be allocated to SPM. These variables turn out to represent a majority of all data accesses in many programs. Second, this provides support for allocating variables within recursive programs. Third, we support allocation of temporary variable (PC-relative addressing). Fourth, we have developed a simulator to obtain cycle-accurate information on memory behavior. In [3], the costs of allocation were not modeled, nor were the behaviors of the ARM¡¦s complex memory subsystem. Keywords: SPM, memory allocation, memory modeling, library variables, WCET
435

Theory of Constraints applied to multi-project management in resource allocation and monitoring mechanisms

Huang, Ching-ju 17 February 2012 (has links)
As the world¡¦s high degree of urbanization, greenhouse gas emission by vehicles, home appliances and industrial production is increasing year by year and according to the UNEP (United Nations Environment Programme) report urban carbon-dioxide emissions accounted for 80% of total global emissions. In order to encourage the alternative energy development, Taiwan government actively promotes the subsidy for alternative energy implementation, thus making the solar energy industry booming in recent years. Based on the government procurement competition mechanism, the procurement competition needs to be transparent and fair. Faced with competition in the industry, companies must reduce costs and improve quality while also required to enhance the customer satisfaction. Therefore, a good engineering project control becomes the most important factor to enhance a company's competitive ability. Particularly, when professional management is getting more and more important nowadays, solar energy system¡¦s building construction is not only limited to technology and equipment level, but also the enterprise configuration of internal human resources and outsourcing. Moreover, how to minimize cost and how to use efficient way to make the project work on schedule are the important issues for policy makers. This study is based on a domestic solar systems engineering project, and focuses on the distribution and configuration of the limited internal and external resources of multiple projects in progress. It uses the Critical Chain Project Management in the Theory of Constraints to break through limitations. VBA programming is used to find the minimum cost of human resource conflict in the project scheduling, furthermore Arena simulation system is utilized to establish the best configuration of human resources deployment to provide decision-making mechanism. The simulation result is verified that it can really help to provide a decision-making reference to project managers to obtain the ideal scheduling and resource allocation.
436

Power Allocation Based on Limited Feedback in DF Cooperative and Cognitive Radio Networks

Li, Jia-Chi 03 August 2012 (has links)
This thesis investigates cooperative communication under the framework of cognitive radio network, which consists of primary and secondary users(PU & SU). The cooperative and cognitive radio network (CCR) adopts overlay dynamic spectrum access, That is, the SU simultaneously assists PU¡¦s transmission and transmits its own message using spectrum shared by primary user. The secondary user adopts decode-and-forward (DF) relaying to assist the primary user in transmitting message. With secondary user¡¦s assistance, the cooperative system can be treat as an equivalent multiple input single output (MISO) system to attain the spatial diversity of the primary user. The virtual MISO system can reduce the outage probability and enhance the transmission reliability. Under the requirement on primary user's transmission quality, secondary user transmits both user¡¦s signals simultaneously, so that the secondary acquires authority to access spectrum. Based on limited feedback regarding SNR of link between primary transmitter and receiver, secondary user allocates transmission power of primary signal and secondary signal to increase throughput and spectrum efficiency of SU subject to satisfying PU¡¦s outage constraint.
437

The Investigation of Fiscal Position of Kaohsiung County Before and After the Merge of City and County

Lin, Chuan-Ping 15 August 2012 (has links)
The objective of this paper is to discuss the financial status of Kaohsiung city after the impact of the Governing Allocation of Revenues and Expenditures Act and the merge of Kaohsiung city and county. After Kaohsiung city-county consolidation to elevate status on December 25, 2010, the new government, by the law, needs to accept the obligations and responsibilities of Kaohsiung County in addition to the original outstanding debts of two governments. It is therefore interesting to ask if the restructuring of administrative regions policy leads to the budget deficit of the new government too large. To this end, we test whether the Kaohsiung fiscal deficits are too large to be sustaintable over the period 1987-2010. Our empirical results have shown that, at the present system of laws, the fiscal deficits of the Kaohsiung city-county consolidation are satisfied since they are stationary.
438

Fault tolerant control allocation in systems with fixed magnitude discrete controls

Marwaha, Monika 15 May 2009 (has links)
The promise and potential of controllers that can reconfigure themselves in the case of control effector failures and uncertainties, and yet guarantee stability and provide satisfactory performance, has led to fault tolerant control being an active area of research. This thesis addresses this issue with the design of two fault tolerant nonlinear Structured Adaptive Model Inversion control schemes for systems with fixed magnitude discrete controls. Both methods can be used for proportional as well as discrete controls. However, discrete controls constitute a different class of problems than proportional controls as they can take only binary values, unlike proportional controls which can take many values. Two nonlinear control laws based on Structured Adaptive Model Inversion are developed to tackle the problem of control failure in the presence of plant and operating environment uncertainties. For the case of redundant actuators, these control laws can provide a unique solution. Stability proofs for both methods are derived and are presented in this thesis. Fault Tolerant Structured Adaptive Model Inversion that has already been developed for proportional controls is extended here to discrete controls using pulse width modulation. A second approach developed in this thesis is Fault Tolerant Control Allocation. Discrete control allocation coupled with adaptive control has not been addressed in the literature to date, so Fault Tolerant Control Allocation for discrete controls is integrated with SAMI to produce a system which not only handles discrete control failures, but also accounts for uncertainties in the plant and in the operating environment. Fault tolerant performance of both controllers is evaluated with non real-time nonlinear simulation for a complete Mars entry trajectory tracking scenario, using various combinations of control effector failures. If a fault is detected in the control effectors, the fault tolerant control schemes reconfigure the controls and minimize the impact of control failures or damage on trajectory tracking. The controller tracks the desired trajectory from entry interface to parachute deployment, and has an adaptation mechanism that reduces tracking errors in the presence of uncertainties in environment properties such as atmospheric density, and in vehicle properties such as aerodynamic coefficients and inertia. Results presented in the thesis demonstrate that both control schemes are capable of tracking pre-defined trajectories in the presence of control failures, and uncertainties in system and operating environment parameters, but with different levels of control effort.
439

Dynamic resource allocation for energy management in data centers

Rincon Mateus, Cesar Augusto 15 May 2009 (has links)
In this dissertation we study the problem of allocating computational resources and managing applications in a data center to serve incoming requests in such a way that the energy usage, reliability and quality of service considerations are balanced. The problem is motivated by the growing energy consumption by data centers in the world and their overall inefficiency. This work is focused on designing flexible and robust strategies to manage the resources in such a way that the system is able to meet the service agreements even when the load conditions change. As a first step, we study the control of a Markovian queueing system with controllable number of servers and service rates (M=Mt=kt ) to minimize effort and holding costs. We present structural properties of the optimal policy and suggest an algorithm to find good performance policies even for large cases. Then we present a reactive/proactive approach, and a tailor-made wavelet-based forecasting procedure to determine the resource allocation in a single application setting; the method is tested by simulation with real web traces. The main feature of this method is its robustness and flexibility to meet QoS goals even when the traffic behavior changes. The system was tested by simulating a system with a time service factor QoS agreement. Finally, we consider the multi-application setting and develop a novel load consolidation strategy (of combining applications that are traditionally hosted on different servers) to reduce the server-load variability and the number of booting cycles in order to obtain a better capacity allocation.
440

An Research on Time Allocation for the On-the-job Master Programme Studetns in the National Sun Yat-sen University

Tsai, Janice 27 June 2004 (has links)
In Taiwan, people accepting a higher education are increasing day by day, most of the persons who take an advanced study with the graduate schools. In recent years, the implementation of the recurrent education policy, offer to individuals return to school with the chance to receive a higher education. But as to on-the-job master programme students, it makes students' social role tend towards pluralism and complicated. To participate in receiving an education, they must give consideration to the roles, such as family , working and learner ,etc¡K. Effective time allocation to them becomes relatively important. The purpose of this research lies in understanding that on-the-job master programme students daily activities and time allocation include the sleep, housework, work , child care, sports, prepare lessons, school commute, attend classes ,etc. And understands the conflict state of gain and loss analysis after them start to study in the curriculum of graduate school, and probe into a difference situation change produced by different individuals to analyse the influence main factors of the time allocation and the conflicts. Probe into the basis of obtaining the theory via documents first in this research, and then adopt questionnaire investigation method , have with National Sun Yat-sen University (NSYSU) on-the-job master programme class , master class and class of master credit students as the target, total and elect 327 students and carry on the survey as studying samples, get 302 effective questionnaires. The data we use the statistics methodology to carry on quantitative analysis, and discover that, sketches it as follows: First, the on-the-job student's sample of the master of NSYSU takes the majority with management college , master's class , male , married , with more than one children , full-time-job workers under the age of 40. Secondly, to sum up that on-the-job students¡¦ time allocation , sleep time is 6.50 hours on average every day, housework spend 1.10 hours, spend 8.71 hours at work, child-bearing is 1.19 hours, sport time spend 0.38 hour, prepare lessons time is 1.62 hours; spend 9.45 hours in classes, and spend 3.93 hours for communication to school per week . The third, studying in the gain and loss after attending the graduate school, the on-the-job students showing differences about losses in various fields. They think the most loss is the recreation time; secondly is the loss time of family life , the third are personal health and working time , the least loss is the incomes. The fourth, ¡§time allocation¡¨, ¡§gain and loss¡¨ and ¡§time conflict¡¨ will be different to some extent when changing factors in different backgrounds.

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