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Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown Jan 2009

Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown

Computer Science and Engineering Theses - Archive

The behavior and self-organization of ant colonies has been widely studied and served as the inspiration and source of many swarm intelligence models and related clustering algorithms. Unfortunately, most models that directly mimic ants produce too many clusters and converge too slowly. A wide range of research has attempted to address this issue through various means, but a number of problems remain: 1) Ants must still physically move from one cluster to another through intermediate locations, 2) current methods for remote relocation of an item only consider one movement at time to a particular location and do not consider patterns …

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An Auction Mechanism For Grid Scheduling And Resource Allocation In The Context Of Atlas, Tengkok Aaron Thor Jan 2009

An Auction Mechanism For Grid Scheduling And Resource Allocation In The Context Of Atlas, Tengkok Aaron Thor

Computer Science and Engineering Dissertations - Archive

The technological advancements in the areas of computing and networking over the recent years have led to an emerging infrastructure known as Computational Grids, which provides users with the flexibility of pervasive access to enormous computational resources hosted at remote locations. Effective resource management and job scheduling poses a challenge when constraints such as resource utilization, response time, global and local policies need to be taken into account, while dealing with potentially independent sources of jobs, computational, and storage resources. It must be ensured that scheduling decisions made are still valid by the time a job is to be executed, …

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Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere Jan 2009

Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere

Computer Science and Engineering Theses - Archive

In recent years, the number of smartphone users has increased by many folds. In fact, it is estimated to reach 100 million by 2013. Current generation of smartphones has better storage, battery, computing capabilities and they come equipped with short range communication technologies like Bluetooth and Wi-Fi. These improved capabilities coupled with staggering rise in number of users, has prompted growing interest in smartphone applications that help users to communicate with each other directly and over the internet. In particular as a result, when a large number of mobile users can communicate directly with each other during opportunistic contacts when …

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Reactive Control Composition For Mobile Manipulators, Binu George Mathew Jan 2009

Reactive Control Composition For Mobile Manipulators, Binu George Mathew

Computer Science and Engineering Theses - Archive

A mobile manipulator is a manipulator mounted on a mobile platform. Due to this combination it has increased mobility compared to a fixed manipulator and increased dexterity compared to a mobile platform. At the same time it has a significantly higher number of degrees of freedom than fixed manipulators or mobile platforms and an increased task and workspace. In particular, the size of the workspace of the manipulator is restricted only by the workspace limitations of the mobile platform and the obstacles around the goal location. In addition, the extra degrees of freedom increase the number of ways in which …

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Millimeter Scale Robots For The Nanofactory, Rakesh Murthy Jan 2009

Millimeter Scale Robots For The Nanofactory, Rakesh Murthy

Electrical Engineering Dissertations - Archive

The top down approach is a commonly employed miniaturization pathway into micro and nanomanufacturing. Its popularity is due to the fact that it adapts traditionally engineered macro scale positioning, manipulation and processing technology with micro and nano scale precision and part sizes. However, state of the art top down systems such as the Atomic Force Microscope (AFM) span four to five orders of magnitude larger than the parts being handled. This dissertation addresses the need for creating millimeter size robotic positioning technology that closes the size gap between equipment and part sizes. Such microrobot manufacturing methodology comprising of micro component-level …

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Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan Jan 2009

Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan

Computer Science and Engineering Theses - Archive

In the past several years, wireless mobile devices with advanced computing, sensing, and storing capabilities have been increasingly developed by handset manufacturers, deployed by wireless carriers, and accepted by consumers. A prominent example is the vast success of Apple's iPhone, which witnessed a sale of 1 million units during the first 3 days of sales for its new version iPhone 3GS. As a result of the increasing popularity of these mobile devices, users can carry, utilize, and exchange information embedded therein, ideally wherever they go and whenever they want. A prominent scenario is where information is exchanged among users when …

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Online Adaptive Optimal Control For Continuous-Time Systems, Draguna Vrabie Jan 2009

Online Adaptive Optimal Control For Continuous-Time Systems, Draguna Vrabie

Electrical Engineering Dissertations - Archive

This work makes two major contributions. * First, in the field of computational intelligence, it develops reinforcement learning controllers (i.e. approximate dynamic programming algorithms) for continuous-time systems, whereas in the past, reinforcement learning has been mainly developed for discrete-time systems. * Second, in the field of control systems engineering, it develops on-line optimal adaptive controllers, whereas in the past, optimal control has been an off-line design tool, and on-line adaptive controllers have not been optimal. The online algorithms presented herein are reinforcement learning schemes which provide online synthesis of optimal control for a class of nonlinear systems with unknown drift …

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The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale Jan 2009

The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale

Computer Science and Engineering Theses - Archive

Structured peer-to-peer systems are distributed communication systems that typically use Distributed Hash Table (DHT) indexing to efficiently locate the resources. These networks are highly scalable and can route the messages correctly even for the extremely dynamic environment. But these networks are vulnerable; even a small fraction of malicious nodes can bias the lookup results when they are present on a lookup path. In our thesis, we address this problem of reliably searching the insecure p2p networks. We propose a reputation system to reduce the number of failed lookups and make the networks more robust. For our study, the concept is …

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Automated 3d Microassembly With Precision Adjusted Hybrid Supervisory Controller, Choudhury Aditya Narayan Das Jan 2009

Automated 3d Microassembly With Precision Adjusted Hybrid Supervisory Controller, Choudhury Aditya Narayan Das

Electrical Engineering Dissertations - Archive

Unlike semiconductor integrated circuits (ICs), newer microsystems combine sensors, actuators, mechanical structures, electronics, and optics on a single substrate. In such a diversified system, heterogeneous manipulation of the components becomes unavoidable. In an effort to find a solution to reduced yields and speeds in manufacturing at the micro-scale, research initiated in 1990s has sought to understand top-down aspects of micromanipulation, sensor-based precision control of robots, self alignment effects using compliant micro structure designs, and so on. From these researches, automated microassembly emerges as an enabling technology for micro manufacturing that offers well-known pathways to building heterogeneous microsystems with a higher …

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A Microfluidic Platform To Study Cell Migration, Smitha Malalur Nagaraja Rao Jan 2009

A Microfluidic Platform To Study Cell Migration, Smitha Malalur Nagaraja Rao

Electrical Engineering Dissertations - Archive

Migration of cancer cells from the primary organ to distant sites is critical to the development of malignant metastasis. This is partly dependant on the various chemical factors present in the blood serum. Cell motility studies using conventional Boyden chamber assays require high volumes of reagents. The measurement provides only an end-point result and time-lapse study of the cell deformation and migration cannot be performed. We have designed and evaluated a poly-dimethylsiloxane (PDMS) microfluidic device in order to study cell migration in the presence of gradients. Photolithography and soft lithography processes were used to fabricate the PDMS devices from the …

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Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls Jan 2009

Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls

Computer Science and Engineering Theses - Archive

Covert timing channels provide a way to surreptitiously leak information from an entity in a higher-security level to an entity in a lower level. The difficulty of detecting or eliminating such channels makes them a desirable choice for adversaries that value stealth over throughput. When one considers the possibility of such channels transmitting information across network boundaries, the threat becomes even more acute. A promising technique for detecting covert timing channels focuses on using entropy-based tests. This method is able to reliably detect known covert timing channels by using a combination of entropy and conditional entropy to detect anomalies in …

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Performance Analysis And Comparison Of Dirac Video Codec With H.264 / Mpeg-4 Part 10 Avc, Aruna Ravi Jan 2009

Performance Analysis And Comparison Of Dirac Video Codec With H.264 / Mpeg-4 Part 10 Avc, Aruna Ravi

Electrical Engineering Theses - Archive

Dirac is a hybrid motion-compensated state-of-the-art video codec that uses modern techniques such as wavelet transforms and arithmetic coding. It is an open technology, designed to avoid patent infringement and can be used without the payment of license fees. It is well suited to the business model of public service broadcasters as it can be easily recreated for new platforms. Dirac is aimed at applications ranging from HDTV (high definition television) to web streaming.H.264, MPEG-4 part-10 or AVC, is the latest digital video codec standard which has proven to be superior than earlier standards in terms of compression ratio, quality, …

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Ionization Competitors Extend The Linear Range Of Electrospray Ionization Mass Spectrometry, Bilal H. Bazzi Jan 2009

Ionization Competitors Extend The Linear Range Of Electrospray Ionization Mass Spectrometry, Bilal H. Bazzi

Chemistry & Biochemistry Theses - Archive

ESI-MS has proven its applicability in quantitative analysis for a wide range of analytes. Its effectiveness relies on achieving sensitivity and linear range, although the latter is known to be limited. ESI-MS response varies among charged species due to differences in analyte structure. The working curve associated with quantitative analysis has a limit of linearity. At high analyte concentration, instrument response plateaus because the surface of the charged droplet reaches saturation. Several studies have proposed to enhance the linear range by enhancing gas-phase analyte charging, by facilitating droplet evaporation, or by improving ion transmission through the mass spectrometer. This thesis …

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Ecomorphology Of The Mexican Fence Lizards Of The Sceloporus Formosus Group (Squamata: Phrynosomatidae), Gloria Andrea Acevedo Jan 2009

Ecomorphology Of The Mexican Fence Lizards Of The Sceloporus Formosus Group (Squamata: Phrynosomatidae), Gloria Andrea Acevedo

Biology Theses - Archive

A central belief of ecomorphological studies is the link between morphology and performance, but, surprisingly few analyses demonstrate this relationship. Fence lizards of the genus Sceloporus offer a useful system for addressing correlations between morphology and performance because they possess keratinized and keeled scales, a distinctive morphological character that might influence water balance. A common observation across different taxa of reptiles is that many organisms in dry habitats have few scales on their bodies, compared to organisms inhabiting moist environments. This pattern is also present in fence lizards. I investigated if the number of dorsal and lateral scales varies across …

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A New Method For Non-Rigid Registration Of 3d Images, Mehmet Ali Akinlar Jan 2009

A New Method For Non-Rigid Registration Of 3d Images, Mehmet Ali Akinlar

Mathematics Dissertations - Archive

In this dissertation we present a novel method for the nonrigid registration of 3D images using a well-established mathematical framework mostly known as the deformation based grid generation method. The deformation based grid generation method is able to generate a grid with desired grid density distribution that is free from grid folding. This method gives direct control over the cell size of the adaptive grid and determines the node velocities directly. The adaptive grid system naturally distributes more grids to deprived areas. The positive monitor function disallows grid folding and provides a mean to control the ratio of the areas …

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Analysis Of Novel Regulatory Region And Function Of A Young Drosophila Retrogene: Dntf-2r, Mansi Motiwale Kunte Jan 2009

Analysis Of Novel Regulatory Region And Function Of A Young Drosophila Retrogene: Dntf-2r, Mansi Motiwale Kunte

Biology Dissertations - Archive

Dntf-2r is a young retroposed gene that originated from the nuclear transport gene Dntf-2. Here the function, quality and evolutionary origin of the regulation of this retrogene are explored. In Chapter 1, I introduce the background of what is known of Dntf-2r as well as the function of its parental gene. This includes their evolutionary histories, and known functional and regulatory aspects. Chapter 2 describes my work on the novel regulatory region recruited by the retrogene and I explore the tissue specific expression pattern (i.e. testis expression) driven by this region. In Chapter 3 I set myself up to review …

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Non-Traditional Socio-Mathematical Norms In Undergraduate Real Analysis, Paul Christian Dawkins Jan 2009

Non-Traditional Socio-Mathematical Norms In Undergraduate Real Analysis, Paul Christian Dawkins

Mathematics Dissertations - Archive

This study builds upon the framework of classroom norms (Cobb, Wood, & Yackel, 1993) and socio-mathematical norms (Cobb & Yackel, 1996) to understand how non-traditional socio-mathematical norms influence student reasoning and transitions to advanced mathematical thinking in undergraduate real analysis. The research involves a qualitative investigation of classroom instruction and interactions, student and instructor interviews, and class exams. The study explores the roles of each norm as the students constructed understanding of advanced mathematics and transitioned to advanced mathematical thinking. I define "non-traditional" according to research accounts of traditional instruction in proof-based mathematics courses and considerations on the culture of …

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Enantiomeric Separation, Microorganism Studies And Determination Of Binding Constants Using Capillary Electrophoresis, Chunxia Jiang Jan 2009

Enantiomeric Separation, Microorganism Studies And Determination Of Binding Constants Using Capillary Electrophoresis, Chunxia Jiang

Chemistry & Biochemistry Dissertations - Archive

Enantiomeric separation of three series of compounds, including β-lactams, synthetic amino acids and ruthenium(II) polypyridyl complexes using different modes of capillary electrophoresis are discussed in this dissertation. Enantiomeric recognition mechanisms are explored by studying the effect of the structures of chiral selectors and analytes. Results indicated that the size correlation between the analyte and the cyclodextrin cavity size play an important role in enantioseparation. Effects of experimental parameters including chiral selector concentration, buffer additive type and concentration, run buffer pH and applied voltage are studied for optimization of the enantioseparations. A new class of chiral selectors, cyclofructans were developed and …

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College Student Risk Behavior: Implications Of Religiosity And Impulsivity, Mary Cazzell Jan 2009

College Student Risk Behavior: Implications Of Religiosity And Impulsivity, Mary Cazzell

Nursing Dissertations - Archive

College student risk-taking among 18 to 21 years olds includes smoking cigarettes, binge drinking, casual sex with multiple partners, automobile accidents due to risky driving or driving under the influence, and substance use. Among 10 to 24 year olds, 72% of all fatalities result from automobile accidents, unintended injuries, homicide, and suicide. Since not all college students participate in risk behaviors, protective factors such as religiosity may be a protective social or psychological buffer that supports positive relationships and moral order. Impulsivity, an inability to squelch inappropriate thoughts or actions, is associated with the later development (in the mid-twenties) of …

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Large Deviation Principle For Functional Limit Theorems, Adina Oprisan Jan 2009

Large Deviation Principle For Functional Limit Theorems, Adina Oprisan

Mathematics Dissertations - Archive

We study a family of stochastic additive functionals of Markov processes with locally independent increments switched by jump Markov processes in an asymptotic split phase space. Based on an averaging limit theorem, we obtain a large deviation result for this stochastic evolutionary system using a weak convergence approach. Examples, including compound Poisson processes, illustrate cases in which the rate function is calculated in an explicit form.We prove also a large deviation principle for a class of empirical processes associated with additive functionals of Markov processes that were shown to have a martingale decomposition. Functional almost everywhere central limit theorems are …

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Thermal Tolerance, Physiologic Condition, And Population Genetics Of Dreissenid Mussels (Dreissena Polymorpha And D. Rostriformis Bugensis) Relative To Their Invasion Of Waters In The Western United States, John T. Morse Jan 2009

Thermal Tolerance, Physiologic Condition, And Population Genetics Of Dreissenid Mussels (Dreissena Polymorpha And D. Rostriformis Bugensis) Relative To Their Invasion Of Waters In The Western United States, John T. Morse

Biology Dissertations - Archive

Zebra mussels, Dreissena polymorpha, and quagga mussels, D. rostriformis bugensis, Eurasian freshwater bivalves, invaded the North American (NA) Great Lakes in the mid 1980's. Subsequently, they invaded water bodies east of the Rocky Mountains. Their more recent expansion into warm, isolated, southwestern U.S. water bodies suggests that both species are developing thermally-tolerant physiological races. Chronic upper thermal tolerance limits were determined for D. polymorpha populations from Winfield City Lake (KS) (WCL), Lake Oologah (OK) (OL) and Hedges Lake (NY) (HL), and the D. rostriformis bugensis population from Lake Mead (NV/AZ) (LM). Individuals from WCL had 12-d and 28-d incipient upper …

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Geochemistry Of Molybdenum In The Aquia Aquifer, Maryland, Usa, Teresa Iafelice Valle Jan 2009

Geochemistry Of Molybdenum In The Aquia Aquifer, Maryland, Usa, Teresa Iafelice Valle

Earth & Environmental Sciences Theses - Archive

The present study contributes to the understanding of controls on and behavior of molybdenum (Mo) in an aquifer, and its potential as an indicator of changing redox conditions along the groundwater flowpath. The central hypothesis of the present work is that the hydrogeochemical evolution along two separate groundwater flowpaths of the Aquia Aquifer, Maryland, USA, one each on the Eastern and Western Shore of Chesapeake Bay, consists of chemical weathering and oxidation-reduction reactions that dictate the degree of Mo mobilization, as well as mineral co-precipitation/re-adsorption reactions that dictate the degree of Mo immobilization (i.e., scavenging). This hypothesis is evaluated by …

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Sex, War And Disease: The Effects Of Infection On Horn Size And Intra-Sexual Competition In The Broad-Horned Flour Beetle, Gnathocerus Cornutus, Amrita Naidu Jan 2009

Sex, War And Disease: The Effects Of Infection On Horn Size And Intra-Sexual Competition In The Broad-Horned Flour Beetle, Gnathocerus Cornutus, Amrita Naidu

Biology Theses - Archive

Sexual selection is widely used to explain the evolution of mating systems where most often it is manifest as the competition among males for access to females. This competition takes the form of direct male-male interactions in broad-horned flour beetle Gnathocerus cornutus and often results in exaggerated male phenotypes. Sexually selected traits are interesting because in many cases their existence appears to contradict natural selection. For example, the "handicap hypothesis" suggests that there may be a trade-off between immune response and horn size because mounting an immune response necessary for survival (natural selection) may divert resources away from growing longer …

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Logistic Regression With Misclassified Covariates Using Auxiliary Data, Nathan N. Dong Jan 2009

Logistic Regression With Misclassified Covariates Using Auxiliary Data, Nathan N. Dong

Mathematics Dissertations - Archive

When standard regression methods are used, measurement errors cause a bias in parameters estimation. In dealing with discrete covariates, such measurement errors are known as misclassification and the corresponding discrete covariate is said to be misclassified. Even though the collected data may not be fully reliable, it may be possible to collect some sub-data with full precision called auxiliary data and the remaining data called primary data may contain misclassification. In this paper, in order to improve predictions from the primary data with misclassification, we propose a method based on the maximum likelihood approach; by using the prediction with auxiliary …

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Removal Of Butylene And Propylene Gas Using Biofiltration, Madhu Rani Jan 2009

Removal Of Butylene And Propylene Gas Using Biofiltration, Madhu Rani

Earth & Environmental Sciences Theses - Archive

Air pollutants are produced from a variety of anthropogenic activities such as food production, wastewater treatment plants, painting, industrial activities, and biomass combustion. Such pollutants are becoming a cause of concern worldwide because of their harmful effects on ecosystems, human health, and the atmosphere. One technology for treatment of these hazardous, odorous, and ozone-forming compounds is biofiltration. Biofilters are relatively inexpensive to install and operate, and can achieve high pollution removal efficiencies. This research was carried out to determine the removal efficiency of pollutants propylene and butylene using biofilter technology. In a biofilter column, air is passed through a packed …

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Optimal Control Approach To Image Registration, Stephen Taiwo Salako Jan 2009

Optimal Control Approach To Image Registration, Stephen Taiwo Salako

Mathematics Dissertations - Archive

The purpose of this dissertation is twofold: To present a new method of orthogonal grid generation and to investigate certain theoretical aspects of the optimal control approach to the image registration problem.In the first part of this dissertation, we will present a variational method of orthogonal grid generation which is based on the deformation method and solving Euler-Lagrange equations. Although the concept of grid generation has been studied extensively, the generation of orthogonal grids is still one of the most challenging problems of the grid generation methods.An orthogonal grid should offer significant advantages in the solution of systems of partial …

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Phonological Processes In Contemporary Spoken Bulgarian, Zdravka Radkova Jan 2009

Phonological Processes In Contemporary Spoken Bulgarian, Zdravka Radkova

Linguistics & TESOL Dissertations - Archive

This study investigates a number of phonological processes observed in the speech of 24 educated Bulgarian speakers. The speech of all subjects was recorded during 30 minute interviews conducted in 2004. Three speech styles were elicited - reading passage, interview and phone conversation - and later transcribed for analysis. Statistical Variable rule analysis was used to investigate the observed patterns of variation in speech. Different internal and external linguistic variables were found to impact the processes of vowel and consonant deletion in speech. Overall, what this study has established is that although certain socio-linguistic factors such as speaker's sex, regional …

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The Culture Industry, Hip Hop Music, And The White Perspective: How One Dimensional Representation Of Hip Hop Music Has Influenced White Racial Attitudes, Walter Edward Hart Jan 2009

The Culture Industry, Hip Hop Music, And The White Perspective: How One Dimensional Representation Of Hip Hop Music Has Influenced White Racial Attitudes, Walter Edward Hart

Sociology & Anthropology Theses - Archive

This theoretical study builds from Ben Agger's theory in his 1992 book, Cultural Studies as Critical Theory:The ideological outcomes of the culture industry are in a sense unintended; they emerge in the interplay of authorial, directorial, and audience assumptions about the nature of the world. (Agger 1992:65)I theorize the effect of the culture industry's cycle of assumptions on the one-dimensional representation of hip hop music and its reflection and reinforcement of Whites' perceptions of Blacks and Black Culture. The reinforcement of Whites' historically negative racial attitudes emerge unintended through a complex cycle of assumptions between the director (culture industry), the …

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Historical Archaeology At The Berachah Rescue Home: A Holistic Approach And Analysis Of An Industrial Homestead In Arlington, Texas, Cody Shane Davis Jan 2009

Historical Archaeology At The Berachah Rescue Home: A Holistic Approach And Analysis Of An Industrial Homestead In Arlington, Texas, Cody Shane Davis

Sociology & Anthropology Theses - Archive

Excavations at the historic Berachah Rescue Home in Arlington, Texas were undertaken as part of the 2003 and 2004 University of Texas at Arlington (UTA) Archaeological Field Schools. The excavations explored several features surrounding the Berachah Rescue Home Cemetery on UTA property. The site was heavily disturbed by bulldozing activities and the expansion of surrounding neighborhoods and UTA. The conjunctive approach, as described by Walter Taylor (1983), for analysis of historic archaeological sites was utilized to understand the fullest cultural context of Berachah Rescue Home. Three components, archival research, oral histories, and archaeological data, were examined to reconstruct this historic …

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The Facial Masculinity Of Women In Sex Segregated Occupations, Chawki Ahmed Belhadi Jan 2009

The Facial Masculinity Of Women In Sex Segregated Occupations, Chawki Ahmed Belhadi

Sociology & Anthropology Theses - Archive

This purpose of the study was to bring more definition to the "problem" of occupational sex segregation, specifically why male-dominated occupations like engineering, firefighting, and the military still remain sex segregated. The study attempted to do so by integrating two findings: 1) the finding that women in male-dominated occupations are more dominant than women in female-dominated occupations, and 2) the finding that facially masculine women are more dominant than facially submissive women. Facial photos of women from occupations that are at least 90% male dominated and at least 90% female dominated were culled from the internet and rated for their …

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