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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.
21

Visitor Satisfaction at a Local Festival: An Importance-Performance Analysis of Oktoberfest

Gardi, Andrea January 2014 (has links)
The aim of this research was to provide a practical method for assessing visitor satisfaction at a local festival. It is crucial for festival management to monitor and evaluate visitor satisfaction in order to understand and identify the needs and perceptions of attendees, which in turn allows organizers to design and tailor the festival elements towards them, leading to higher visitor satisfaction, positive word-of-mouth advertising, and increased likelihood of repeat attendance (Lee, Lee and Choi, 2011; Lee & Beeler, 2009). The research objectives were to evaluate current levels of satisfaction of festival attendees, to determine what attributes are importance in determining satisfaction, and to analyze whether importance and performance of those attributes differs based on demographics and visit characteristics, with the aim of recommending policies to assist the festival in increasing overall visitor satisfaction. A questionnaire was distributed over four days, and three event locations resulting in the collection of 389 completed questionnaires. Respondents were asked to complete demographic and visit information as well as rate the importance and performance of eighteen festival attributes. ANOVA and independent t-tests were used in order to determine whether the importance and satisfaction of these attributes differed based on the demographics and visit characteristics. An Importance-performance analysis (IPA) was then used to assist event organizers in resource allocation while identifying critical performance attributes in order to improve visitor satisfaction. Findings reveal attributes associated with program content, convenience and food and beverage ranked higher in determining visitor satisfaction than the attributes associated with souvenir, transportation and information availability. Results also indicate statistically significant differences of the mean importance and mean performance scores of attributes based on gender, age, resident status, site and whether it was the respondents??? first time at the event. It was found that females place a higher importance on convenience attributes such as the cleanliness of restrooms, helpfulness of staff and feeling of safety, as compared to males. As well, repeat visitors placed a higher importance on program content attributes such as live entertainment, dance space and authentic culture, and also have a higher perception of performance for these attributes than first-time visitors. These findings result in direction for management in where to place future resources, as well as implications for promotional and advertising strategies.
22

Spatial Spectral Efficiency Analysis for Wireless Communications

Zhang, Lei 19 August 2014 (has links)
Spectrum utilization efficiency is one of the primary concerns in the design of future wireless communication systems. Most performance metrics for wireless communication systems focus on either link level capacity or network throughput while ignore the spatial property of wireless transmissions. In this dissertation, we focus on the spatial spectral utilization efficiency of wireless transmissions. We first study the spatial spectral efficiency of single-cell and multi-cell wireless relay systems using area spectral efficiency (ASE) performance metric. We then generalize the performance metric, termed as generalized area spectral efficiency (GASE), to measure the spatial spectral utilization efficiency of arbitrary wireless transmissions. In particular, we first introduce the definition of GASE by illustrating its evaluation for conventional point-to-point transmission. Then we extend the analysis to four different transmission scenarios, namely dual-hop relay transmission, three-node cooperative relay transmission, two-user X channels, and underlay cognitive radio transmission. Finally, we apply the GASE performance metric to investigate the spatial spectral efficiency of wireless network with Poisson distributed nodes and quantify the spatial spectral opportunities that could be explored with secondary cognitive systems. Our research on the spatial spectral utilization efficiency provides a new perspective on the designing of wireless communication systems, especially on the transmission power optimization and space-spectrum resource exploitation. / Graduate / 0544 / leizhang@uvic.ca
23

Design and Performance Analysis of Efficient Cooperative Wireless Communication Systems

Altubaishi, Essam Saleh 10 August 2012 (has links)
Cooperative communication has recently become a key technology for modern wireless networks such as 3GPP long-term evolution and WiMAX, because in such networks the transmission rate, the communication reliability, and coverage problems could be improved in a cost-effective manner. This, however, faces many design challenges. First, cooperative transmission typically involves a relaying phase which requires extra resources. This may cause a reduction in the spectral efficiency. Second, extra control signaling increases the complexity of operation, which may limit practical implementation. In addition, a wireless channel is time-varying, mainly due to the multipath propagation. As a result, a careful design of efficient cooperative communication systems is required, not only to enhance the spectral efficiency and maintain the quality-of-service (QoS), but also to be practical. In this dissertation, we aim to address the challenges imposed by cooperative communication and wireless transmission, and design the efficient and distributed systems which can be practically implemented in existing wireless systems. The research work is divided into two main topics: 1) adaptive cooperative wireless systems with variable-rate transmission, and 2) cooperative wireless systems with a power consumption constraint. The first topic investigates how the spectral efficiency of cooperative wireless communication systems can be improved while maintaining the QoS in terms of bit error rate and outage probability. The spectral efficiency enhancement is achieved by using three techniques: adaptivity over the relay node (i.e., relay node is active or not), adaptivity over the modulation mode, and relay selection. Based on that, we propose several adaptive cooperative schemes for both the decode-and-forward (DF) and amplify-and-forward (AF) protocols. To evaluate these schemes, we provide performance analysis in terms of average spectral efficiency, average bit error rate (ABER), and outage probability over Rayleigh fading channels. We start with the single-relay cooperative system using DF protocol, in which two adaptive cooperative schemes with variable-rate transmission are proposed. The first scheme, called the minimum error rate scheme (MERS), aims to exploit the transmit diversity to improve the bit error rate. By trading the multiplexing gain against the diversity gain, we propose the second scheme, called the maximum spectral efficiency scheme (MSES), in which cooperative transmission is avoided whenever it is not beneficial. The MERS improves the ABER significantly and achieves equal or better average spectral efficiency compared to the fixed (i.e., non-adaptive) relaying scheme. In contrast, the MSES provides the best average spectral efficiency due to its ability to not only adapt to the channel variation but also to switch between cooperative and non-cooperative transmissions. To further increase the spectral efficiency, we then propose the third scheme, called variable-rate based relay selection (VRRS) scheme, in which a relay node is selected from among the available relay nodes, based on a predefined criterion. Furthermore, we propose two AF adaptive cooperative schemes, mainly to enhance the spectral efficiency. In the first scheme, we introduce a generalized switching policy (GSP) for a single-relay cooperative wireless system that exploits the variable-rate transmission and useful cooperative regions. The second scheme, called the AF efficient relay selection (AFERS) scheme, extends the GSP to also consider the relay selection technique. Analytical and simulation results verify that the AFERS scheme not only outperforms conventional direct transmission in terms of the average spectral efficiency, but also the AF fixed relaying and the outage-based AF adaptive cooperative scheme. The second topic investigates the fair power consumption of the relay nodes for AF cooperative wireless communication systems. The fairness is defined as to achieve equal power consumption over the relay nodes. We focus on how the relay selection process can be controlled in a distributed manner so that the power consumption of the relay nodes can be included in relay selection. We first introduce a simple closed-form expression for the weight coefficient used in order to achieve the considered fairness that depends only on the local average channel conditions of the relay path. We then derive closed-form expressions of the weighted outage probability and ABER and show that our proposed strategy not only has less complexity than the conventional centralized one but also provides better accuracy in distributing the total consumed power equally among the relay nodes without affecting the performance.
24

Improving OpenMP Productivity with Data Locality Optimizations and High-resolution Performance Analysis

Muddukrishna, Ananya January 2016 (has links)
The combination of high-performance parallel programming and multi-core processors is the dominant approach to meet the ever increasing demand for computing performance today. The thesis is centered around OpenMP, a popular parallel programming API standard that enables programmers to quickly get started with writing parallel programs. However, in contrast to the quickness of getting started, writing high-performance OpenMP programs requires high effort and saps productivity. Part of the reason for impeded productivity is OpenMP’s lack of abstractions and guidance to exploit the strong architectural locality exhibited in NUMA systems and manycore processors. The thesis contributes with data distribution abstractions that enable programmers to distribute data portably in NUMA systems and manycore processors without being aware of low-level system topology details. Data distribution abstractions are supported by the runtime system and leveraged by the second contribution of the thesis – an architecture-specific locality-aware scheduling policy that reduces data access latencies incurred by tasks, allowing programmers to obtain with minimal effort upto 69% improved performance for scientific programs compared to state-of-the-art work-stealing scheduling. Another reason for reduced programmer productivity is the poor support extended by OpenMP performance analysis tools to visualize, understand, and resolve problems at the level of grains– task and parallel for-loop chunk instances. The thesis contributes with a cost-effective and automatic method to extensively profile and visualize grains. Grain properties and hardware performance are profiled at event notifications from the runtime system with less than 2.5% overheads and visualized using a new method called theGrain Graph. The grain graph shows the program structure that unfolded during execution and highlights problems such as low parallelism, work inflation, and poor parallelization benefit directly at the grain level with precise links to problem areas in source code. The thesis demonstrates that grain graphs can quickly reveal performance problems that are difficult to detect and characterize in fine detail using existing tools in standard programs from SPEC OMP 2012, Parsec 3.0 and Barcelona OpenMP Tasks Suite (BOTS). Grain profiles are also applied to study the input sensitivity and similarity of BOTS programs. All thesis contributions are assembled together to create an iterative performance analysis and optimization work-flow that enables programmers to achieve desired performance systematically and more quickly than what is possible using existing tools. This reduces pressure on experts and removes the need for tedious trial-and-error tuning, simplifying OpenMP performance analysis. / <p>QC 20151221</p>
25

Comparing Donor Segments to a Cause-Based Charity: The Case of the American Lung Association

Keyt, John C., Yavas, Ugur, Riecken, Glen 01 January 2002 (has links)
A slowing economy coupled with new political initiative to rely on faith-based organizations to deal with social ills is raising concerns for cause-based organizations about the level of future donations. In this study, 1,414 survey respondents permitted comparisons between current, lapsed and non-donors to the American Lung Association (ALA) in terms of donation motives and their satisfaction via donating, concern about health issues, perceptions of ALA and demographics. Analyses consisted of analysis of variance, chi-square tests and use of the importance/performance technique. Similarities and differences among the three groups are noted and discussed. Implications for the ALA's fundraising activities are drawn.
26

Unconventional Swept Rotor Design using Open Vehicle Sketch Pad (OpenVSP)

Reddy, Pavan 28 June 2023 (has links)
Rotors are a crucial component of VTOL(vertical take-off and landing) devices like unmanned aerial vehicles (UAVs) or helicopters, etc., By generating a rotational force, they create the necessary thrust to lift and maneuver the vehicle in the air. In recent years, there has been a growing emphasis on developing rotor designs that are more efficient and effective for eVTOL. This has led to the emergence of several unconventional swept rotor designs that can improve aerodynamic and aeroacoustic performance. The present thesis aims to investigate the impact of achieving a balanced sweep distribution across a rotor blade and how it affects aerodynamic performance. The study explores the potential benefits and drawbacks of unconventional swept rotor designs and compares their performance curves to traditional straight rotor designs. The investigation begins with an overview of rotor design criteria and literature on swept rotor designs. A comprehensive design and analysis of the aerodynamic performance of various rotor designs are conducted using NASA's OpenVSP and VSPAero, a low-fidelity solver that implements the Vortex lattice method. The results are then compared with wind tunnel experiments. Based on the load distribution analysis of multiple sweep designs, it is noted that swept rotors exhibit decreased performance at lower advance ratios. However, as the speed or advance ratio increases, the overall performance of swept rotors significantly improves. This conclusion is drawn from the load distribution data obtained for each blade of the rotors, and by comparing the figure of merit (FOM) of various designs. / Master of Science / Picture this: a sleek unmanned aerial vehicle (UAV) soaring through the air, its Propellers whirring efficiently and quietly. What makes this possible? The answer lies in the design of the rotors themselves. Rotors are critical components of UAVs, providing the necessary thrust to lift and maneuver the vehicle in the air. And with the growing demand for more efficient and effective eVTOLs (Vertical take-off and Landing) vehicles, unconventional swept rotor designs have emerged as game-changers in the industry. The present thesis delves into the impact and effects of Parametric swept designs on rotor aerodynamic performance. The study seeks to uncover the potential benefits and drawbacks of these designs and compare their performance curves to traditional straight rotor designs. The study starts by looking at how rotors are designed and what others have done with similar designs. Various rotor designs have been thoroughly examined in terms of their aerodynamic characteristics using NASA's OpenVSP and VSPaero, a low-fidelity solver that uses the Vortex lattice method. To verify the tools, this data are compared with wind tunnel tests. Due to its cheap computing cost, OpenVSP makes it possible to investigate these discoveries in an economical manner. According to the results, swept rotors perform better at higher speeds than conventional rotors.
27

Protestant's Guide To Catholic "Nunsense": A Performance Study And Analysis Of "Sister Mary Hubert"

Endsley, Anita 01 January 2005 (has links)
Anita Endsley will portray the role of Sister Mary Hubert in the musical Nunsense at Seaside Music Theatre in Daytona Beach, Florida from October 28 through November 14, 2005. This parody of convent life in crisis written by Dan Goggin provides a breadth of material for analysis of the genre as well as character analysis. Dissecting the comedy will be the foundation for characteer development. The popularity of this musical among Catholic and non-Catholic audiences have created a market that inspired the writer to extend this theme through five sequels. The commercial success of these musicals suggest a strong connection between the demands of the Catholic doctrine and the foundation for comic relief. A vast amount of research can be incorporated to assist in the analysis of comedy written into Nunsense.
28

Performance analysis of multistage interconnection networks with general traffic

Lin, Hua January 2002 (has links)
No description available.
29

Dynamic Trace-based Analysis of Vectorization Potential of Programs

Nagapattinam Ramamurthi, Ragavendar 19 July 2012 (has links)
No description available.
30

Performance analysis and capacity assignment optimisation of wireless cells with re-use partitioning

Kouvatsos, Demetres D., Awan, Irfan U., Al-Begain, Khalid, Tantos, Sotiris January 2002 (has links)
This paper presents a novel and efficient analytic framework for the performance analysis and capacity-assignment optimisation of a wireless GSM cell employing the Re-Use Partitioning (RUP) policy. RUP splits hierarchically the available bandwidth into multiple layers of frequencies and allows tighter frequency re-use in order to achieve a higher network capacity. In this context, a queueing network model (QNM) of a wireless cell is proposed consisting of a hierarchical layer configuration which is decomposed into individual GE/GE/c/c loss systems each of which is analysed in isolation via a more general maximum entropy (ME) state probability solution, subject to appropriate GE-type flow formulae and mean value constraints. Moreover, a new performance optimisation index is proposed as the weighted average non-blocking probability of traffic over all frequency layers. For illustration purposes, the proposed index is utilised to formulate and solve two capacity-assignment optimisation problems. Numerical examples are included to validate the relative accuracy of the analytic GE-type performance metrics against simulation and assess the optimal re-use partitioning policy of the available bandwidth.

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