Matching Items (43,917)
Description
With tremendous increase in the popularity of networked multimedia applications, video data is expected to account for a large portion of the traffic on the Internet and more importantly next-generation wireless systems. To be able to satisfy a broad range of customers requirements, two major problems need to be solved. The first problem is the need for a scalable representation of the input video. The recently developed scalable extension of the state-of-the art H.264/MPEG-4 AVC video coding standard, also known as H.264/SVC (Scalable Video Coding) provides a solution to this problem. The second problem is that wireless transmission medium typically introduce errors in the bit stream due to noise, congestion and fading on the channel. Protection against these channel impairments can be realized by the use of forward error correcting (FEC) codes. In this research study, the performance of scalable video coding in the presence of bit errors is studied. The encoded video is channel coded using Reed Solomon codes to provide acceptable performance in the presence of channel impairments. In the scalable bit stream, some parts of the bit stream are more important than other parts. Parity bytes are assigned to the video packets based on their importance in unequal error protection scheme. In equal error protection scheme, parity bytes are assigned based on the length of the message. A quantitative comparison of the two schemes, along with the case where no channel coding is employed is performed. H.264 SVC single layer video streams for long video sequences of different genres is considered in this study which serves as a means of effective video characterization. JSVM reference software, in its current version, does not support decoding of erroneous bit streams. A framework to obtain H.264 SVC compatible bit stream is modeled in this study. It is concluded that assigning of parity bytes based on the distribution of data for different types of frames provides optimum performance. Application of error protection to the bit stream enhances the quality of the decoded video with minimal overhead added to the bit stream.
Contributors
Sundararaman, Hari (Author) / Reisslein, Martin (Thesis advisor) / Seeling, Patrick (Committee member) / Tepedelenlioğlu, Cihan (Committee member) / Arizona State University (Publisher)
Created
2011
Description
As a significant level of the reformation and transformation of our society has been provoked by environmental deterioration, ecological approaches in environmental design have drawn much attention from professionals as an alternative world view and also as a practical design approach. Particularly in landscape architecture, ecological understanding has been at the very core of the profession since its emergence and plays an important role in the decision making processes. While ecology supports the profession with an objective rationale, aesthetics plays another major role in providing various understandings about the aesthetic experience of people, which is rather subjective. However, the ways to seek the balance between them are still controversial. Furthermore, the conventional aesthetic value system of landscape appears to have limitations for guiding us to an appropriate appreciation, especially in dealing with newly emerging urban landscape patterns such as regeneration of post-industrial landscapes. Understanding these issues, there have been continuous attempts to describe the relation between ecology and aesthetics, suggesting that a new approach known as "ecological aesthetics," can bring us a new set of viewpoints seeking a reunion of nature and culture, and science and art. It asserts that "there is a type of beauty" in the landscape associated with its ecological health which people could aesthetically appreciate; and therefore, revealing the "hidden" beauty of nature in more visible ways should be the primary concern of today's ecological designers. This research mainly consists of extensive literature research and a case study on two landscape restructuring projects of post-industrial landscapes in Seoul, Korea. The literature research redefines the tasks of landscape architecture based on the idea of ecological aesthetics, and the case study seeks the potentials and limitations of current design projects. This research proposes a framework for landscape perception and reflects on the lessons that would be useful for better practice and research.
Contributors
Min, Byoung Wook (Author) / Cook, Edward (Thesis advisor) / Crewe, Katherine (Committee member) / Pijawka, David (Committee member) / Arizona State University (Publisher)
Created
2011
Description
ABSTRACT The purpose of this study was to determine the energy cost of four modes of resistance training (push-ups, pull-ups, curl-ups, lunges). Twelve well trained men aged 23.6 (SD=2.84) years were recruited to participate in the study. Each of the 12 men completed three trials of each of the four exercises on one visit to the laboratory lasting slightly over one hour (M=72 min, SD=5.9 min). The oxygen consumption of the men was monitored constantly throughout the trial and data was recorded every five seconds. Mean VO2 values were calculated for each exercise. The values for push-ups (M=11.57 ml/kg/min, SD=1.99), curl-ups (M=10.99 ml/kg/min, SD=1.48), pull-ups (M=10.87 ml/kg/min, SD=2.51), and lunges (M=14.18 ml/kg/min, SD=1.78) were converted to METs (Metabolic Equivalents). The MET values (3.31, 3.14, 3.11, and 4.05 respectively) all fall within the range of moderate intensity activity. The findings of this study show that a single set of any of the above exercises will qualify as a moderate intensity activity and can be used to meet recommendations on daily physical activity.
Contributors
Vezina, Jesse (Author) / Ainsworth, Barbara (Thesis advisor) / Campbell, Kathryn (Committee member) / Woodruff, Larry (Committee member) / Arizona State University (Publisher)
Created
2011
Description
This research describes software based remote attestation schemes for obtaining the integrity of an executing user application and the Operating System (OS) text section of an untrusted client platform. A trusted external entity issues a challenge to the client platform. The challenge is executable code which the client must execute, and the code generates results which are sent to the external entity. These results provide the external entity an assurance as to whether the client application and the OS are in pristine condition. This work also presents a technique where it can be verified that the application which was attested, did not get replaced by a different application after completion of the attestation. The implementation of these three techniques was achieved entirely in software and is backward compatible with legacy machines on the Intel x86 architecture. This research also presents two approaches to incorporating software based "root of trust" using Virtual Machine Monitors (VMMs). The first approach determines the integrity of an executing Guest OS from the Host OS using Linux Kernel-based Virtual Machine (KVM) and qemu emulation software. The second approach implements a small VMM called MIvmm that can be utilized as a trusted codebase to build security applications such as those implemented in this research. MIvmm was conceptualized and implemented without using any existing codebase; its minimal size allows it to be trustworthy. Both the VMM approaches leverage processor support for virtualization in the Intel x86 architecture.
Contributors
Srinivasan, Raghunathan (Author) / Dasgupta, Partha (Thesis advisor) / Colbourn, Charles (Committee member) / Shrivastava, Aviral (Committee member) / Huang, Dijiang (Committee member) / Dewan, Prashant (Committee member) / Arizona State University (Publisher)
Created
2011
Description
ABSTRACT The Phoenix Four Rivers Flora is an inventory of all the vascular plants growing along the Salt, Gila, New and Agua Fria Rivers, and their tributaries in the Phoenix Metropolitan Area during the years of the study (2009-2011). This floristic inventory documents the plant species and habitats that exist currently in the project area, which has changed dramatically from previous times. The data gathered by the flora project thus not only documents how the current flora has been altered by urbanization, but also will provide a baseline for future ecological studies. The Phoenix Metropolitan Area is a large urbanized region in the Sonoran Desert of Central Arizona, and its rivers are important for the region for many uses including flood control, waste water management, recreation, and gravel mining. The flora of the rivers and tributaries within the project area is extremely diverse; the heterogeneity of the systems being caused by urbanization, stream modification for flood control, gravel mining, and escaped exotic species. Hydrological changes include increased runoff in some areas because of impermeable surfaces (e.g. paved streets) and decreased runoff in other areas due to flood retention basins. The landscaping trade has introduced exotic plant species that have escaped into urban washes and riparian areas. Many of these have established with native species to form novel plant associations.
Contributors
Jenke, Darin (Author) / Landrum, Leslie R. (Committee member) / Pigg, Kathleen B. (Committee member) / Makings, Elizabeth (Committee member) / Arizona State University (Publisher)
Created
2011
Description
The crime of human trafficking has received increased national attention over the past decade. However, the subject of human trafficking is rarely mentioned in criminal justice and criminology curricula in colleges and universities. This study discusses findings from a review of listed courses in 100 criminology and criminal justice bachelor degree programs in colleges and universities in the United States. Implications for further research, including examining criminal justice education programs outside of academe, are discussed. The author advocates adding courses on human trafficking in criminology and criminal justice curricula and makes recommendations for undergraduate criminology and criminal justice education.
Contributors
Zhilina, Tatyana (Author) / Stancliff, Michael (Thesis advisor) / Bernat, Francesc (Committee member) / Vaughan, Suzanne (Committee member) / Arizona State University (Publisher)
Created
2011
Description
The original mediums were not texts or technologies; they were ritual actors performing acts of mediumship. Mediating between determined norms (the status quo) and emergent trends (change), they invoked divine authority to conjure meanings that proved adaptive, nonadaptive and/or maladaptive. With the advent of the written word, ritual became formalized and codified. The medium became a communication device, something abstract and external to the human condition. It then became possible to speak of "media effects" imposing influence in a logical deterministic manner. Yet with the advent of new media, we are witnessing a return to modes of cultural discourse that are spontaneous, interactive, communal and unscripted, all hallmarks of ritual action. This "ritual return" centers on the emergence of the "prosumer" (producer/consumer), a figure actively engaged in mediating practices. While resembling the original archaic "medium" in some respects, the prosumer is a "literate ritualist" allied with a multiplicity of cultural tribes. Thus the "new media" has given rise to "the new medium." The pages that follow focus on acts of contemporary mediumship, examining related concepts such as "ecology," "niche," "role," "affordance," and "trope." Each section considers how specific mediating practices afford and constrain modes of ritualized behavior. I call this practice-oriented approach to media studies "praxism."
Contributors
Gyori, Bradford (Author) / Goggin, Maureen (Thesis advisor) / Baker, Aaron (Committee member) / Hjorleifur Jonsson (Committee member) / Arizona State University (Publisher)
Created
2011
Description
On December 27, 2008, Israel began a military campaign codenamed Operation Cast Lead with an aerial bombardment of the Gaza Strip. On January 3, 2009, Israel expanded its aerial assault with a ground invasion. Military operations continued until January 18, 2009, when Israel implemented a unilateral cease fire and withdrew its forces. When the hostilities had ended, between 1,166 and 1,440 Palestinians had been killed as a result of Israeli attacks, two-thirds of whom are estimated to be civilians. Ensuing allegations of international human rights (IHR) and international humanitarian law (IHL) violations were widespread. Amidst these claims, the United Nations Human Rights Council (UNHRC) commissioned a fact-finding team, headed by South African jurist Richard Goldstone, to investigate whether the laws of war were infringed upon. Their findings, published in a document known colloquially as the Goldstone Report, allege a number of breaches of the laws of occupation, yet give a cursory treatment to the preliminary question of the applicability of this legal regime. This paper seeks to more comprehensively assess whether Gaza could be considered occupied territory for the purposes of international humanitarian law during Operation Cast Lead. In doing so, this paper focuses on exactly what triggers and terminates the laws of occupation`s application, rather than the rights and duties derived from the laws of occupation. This paper proceeds with a brief discussion of the history of the Gaza occupation, including Israel`s unilateral evacuation of ground troops and settlements from within Gaza in 2005, a historic event that sparked renewed debate over Israel`s status as an Occupying Power vis-à-vis Gaza. The following section traces the development of the laws of occupation in instruments of IHL. The next section considers the relevant international case law on occupation. The following section synthesizes the various criteria from the IHL treaty and case law for determining the existence of a situation of occupation, and considers their application to the Gaza Strip during Operation Cast Lead. The concluding section argues that Israel maintained the status of Occupying Power during Operation Cast Lead, and discusses the legal implications of such a determination.
Contributors
Naser, Sam (Author) / Simmons, William (Thesis advisor) / Sylvester, Douglas (Committee member) / Rothenberg, Daniel (Committee member) / Arizona State University (Publisher)
Created
2011
Description
In this dissertation, I focus on a subset of Native American theatre, one that concentrates on peoples of mixed heritages and the place(s) between worlds that they inhabit. As it is an emergent field of research, one goal of this project is to illuminate its range and depth through an examination of three specific points of focus - plays by Elvira and Hortencia Colorado (Chichimec Otomí/México/US), who create theatre together; Diane Glancy (Cherokee/US); and Marie Clements (Métis/Canada). These plays explore some of the possibilities of (hi)story, culture, and language within the theatrical realm across Turtle Island (North America). I believe the playwrights' positionalities in the liminal space between Native and non-Native realms afford these playwrights a unique ability to facilitate cross-cultural dialogues through recentering Native stories and methodologies. I examine the theatrical works of this select group of mixed heritage playwrights, while focusing on how they open up dialogue(s) between cultures, the larger cultural discourses with which they engage, and their innovations in creating these dialogues. While each playwright features specific mixed heritage characters in certain plays, the focus is generally on the subject matter - themes central to current Native and mixed heritage daily realities. I concentrate on where they engage in cross-cultural discourses and innovations; while there are some common themes across the dissertation, the specific points of analysis are exclusive to each chapter. I employ an interdisciplinary approach, which includes theories from theatre and performance studies, indigenous knowledge systems, comparative literary studies, rhetoric, and cultural studies.
Contributors
Noell, Tiffany (Author) / Underiner, Tamara L. (Thesis advisor) / Woodson, Stephani (Committee member) / Brayboy, Bryan (Committee member) / Arizona State University (Publisher)
Created
2011
Description
Rotorcraft operation in austere environments can result in difficult operating conditions, particularly in the vicinity of sandy areas. The uplift of sediment by rotorcraft downwash, a phenomenon known as brownout, hinders pilot visual cues and may result in a potentially dangerous situation. Brownout is a complex multiphase flow problem that is not unique and depends on both the characteristics of the rotorcraft and the sediment. The lack of fundamental understanding constrains models and limits development of technologies that could mitigate the adverse effects of brownout. This provides the over-arching motivation of the current work focusing on models of particle-laden sediment beds. The particular focus of the current investigations is numerical modeling of near-surface fluid-particle interactions in turbulent boundary layers with and without coherent vortices superimposed on the background flow, that model rotorcraft downwash. The simulations are performed with two groups of particles having different densities both of which display strong vortex-particle interaction close to the source location. The simulations include cases with inter-particle collisions and gravitational settling. Particle effects on the fluid are ignored. The numerical simulations are performed using an Euler- Lagrange method in which a fractional-step approach is used for the fluid and with the particulate phase advanced using Discrete Particle Simulation. The objectives are to gain insight into the fluid-particle dynamics that influence transport near the bed by analyzing the competing effects of the vortices, inter-particle collisions, and gravity. Following the introduction of coherent vortices into the domain, the structures convect downstream, dissipate, and then recover to an equilibrium state with the boundary layer. The particle phase displays an analogous return to an equilibrium state as the vortices dissipate and the boundary layer recovers, though this recovery is slower than for the fluid and is sensitive to the particle response time. The effects of inter-particle collisions are relatively strong and apparent throughout the flow, being most effective in the boundary layer. Gravitational settling increases the particle concentration near the wall and consequently increase inter-particle collisions.
Contributors
Morales, Fernando (Author) / Squires, Kyle D. (Thesis advisor) / Wells, Valana L. (Committee member) / Calhoun, Ronald J. (Committee member) / Arizona State University (Publisher)
Created
2011