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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.
361

Kriminalistická balistika / Forensic ballistics

Papírníková, Lenka January 2015 (has links)
The aim of this thesis is to introduce the basic information about the forensic ballistics and about the procedure of ballistic experts. The first chapter is dedicated to clarification the fundamental terms of the subject matter of this thesis. Beside the term of forensic ballistics I also introduce the meaning of some other related terms used in the following text. Next chapter deals with the history and development of the ballistics. The key feature of every ballistic researches are the ballistics marks described in the third chapter. I focus on the ballistic marks division, the origin and occurrence and receiving of these. The gunshot residues are mentioned in their own subchapter. The objects of the ballistic researches, listed in the chapter four, are firearms, ammunition and animate or inanimate target. Next chapter deals with the range of ballistic researches which can be divided into two groups. Within the frame of the identification examination of firearms and ammunition, the individual and group identification of the gun used in a criminal offence is performed. That means the ballistic marks from the seized firearm are compared with the ones detected in a crime scene. Within the frame of the non- identification examination the firearms and ammunition characteristics, the shooting direction,...
362

Rhetoric of trans* identities: public reactions to private confessions

Abele, Kelsey T. January 1900 (has links)
Master of Arts / Department of Communication Studies / Charles Griffin / The year 2015 provided a hotbed of discussion about trans* identities. Caitlyn Jenner’s public announcement of her identity as transgender shortly followed by Rachel Dolezal unveiling as a woman with Caucasian heritage. Using publically accessible interviews such as the Diane Sawyer interview with Bruce Jenner, both of Matt Lauer’s conversations with Dolezal and Jenner, Melissa Harris-Perry’s interview with Dolezal, as well as two Vanity Fair stories provide a space for a closer examination of how trans* identities are negotiated in a conversational setting. Using Hecht’s (1993) communication theory of identity to investigate how the four proposed frames (personal, enactment, relationship, and communal) operate under the lens of trans* identities in flux. This thesis aims to explore the kinds of linguist framing motifs used by both an exemplar of the transgender community and an individual treading the barrier between Caucasian and black identities, ultimately leading to a discussion about how language confines personal and socially structure identity and identification. The implications of this identity work tangles with the reliance on personal experience as an expression of identity and its persuasive power to impact discourse. The linguistic tropes that confine identity expression inherently impact a community of individuals struggling to navigate trans* identity acceptance in a larger sphere.
363

An Analysis of the Radio Frequency Identification (RFID) Technology Implementation within an Independent Public Library System: A Case Study of the North Canton, Ohio Public Library

Lyons, Keith P. 01 January 2010 (has links)
An Analysis of the Radio Frequency Identification (RFID) Technology Implementation within an Independent Public Library System: A Case Study of the North Canton, Ohio Public Library by Keith P. Lyons June 2010 Public libraries require efficient control systems to maintain accurate inventories, statistics, and records of patron borrowing. Generally, public libraries use barcode technology to accomplish these tasks. Radio frequency identification (RFID) has gained the attention of public library personnel in recent years as a replacement for barcodes. RFID implementation contributes to improved staff productivity, increased operational efficiency, and improved item security as well. While potential benefits are significant, issues to consider prior to adoption include system costs, as well as privacy and security concerns. As a consequence of increased patron use and limited budgets, the role of RFID in the public library is promoted as a solution to many of today's challenges. RFID in the public library can assist by improving inventory tracking, improving customer service, and decreasing theft. Using the case study methodology in conjunction with the System Development Life Cycle (SDLC), the author examined RFID use at the North Canton Public Library and its capabilities in improving inventory tracking, providing item security, and supporting customer service. Qualitative data were collected using focused interviews, documentation, direct observation, and participant observation. Findings from this investigation revealed a significant decrease in time required to perform inventory tasks and an increase in time available for library staff to assist patrons. Additionally, evidence demonstrated an increase in the efficiency of patron records due to the automation of the checkout process. Patron privacy and data security were maintained by adherence to RFID implementation guidelines established by the American Library Association (ALA). The findings from this investigation provide public library administrators considering adoption of RFID with a thorough understanding of pre-implementation considerations and the benefits, drawbacks, logistical concerns, and privacy issues that must be addressed for successful results.
364

Perceptions of Complexions: Consciousness and Self-Identification Among Dark-Skinned Blacks

Morris, Brian Kenneth 15 May 2009 (has links)
Skin tone variation within American black communities has long been associated with intraracial stratification. Data from the National Survey of Black Americans (NSBA) indicate that lighter-skinned blacks – net of such factors as region of residence, age, and sex – consistently have higher levels of nearly every socioeconomic indicator including educational attainment, personal and family income, and perceived physical attractiveness when compared to their darker counterparts. What does this color caste system mean for the personal identities and emotional experiences of dark-skinned blacks in America? Using data from the NSBA and six interviews with dark-skinned blacks, I set forth social psychological implications of a phenotypically stratified subgroup in the United States.
365

Customization, emotional bonds and identification with the player character : A study into the effects of text-based gameplay

Hackman, Eleonora January 2016 (has links)
The aim of this study is to take a closer look at how customization, or the lack thereof, affectsthe player to character emotional bond and identification in a digital game. Examining previousarticles and studies with similar aim, the lack of study pertaining to a certain game formatsurfaced and sparked a research interest. To gain some clarity into how character customization,and the identification and bond it inspires in players, would be affected by a non-audiovisualbranching stories digital game the researcher created a small game for this study. This paperexplores if previous research results on RPGs can be transferred to the format of a text-basednon-audiovisual branching story game. For this qualitative study, ten people, divided in twogroups, played a version of the game and answered follow-up questions in the form of aquestionnaire. In addition, some observations were carried out of the game play sessions. Theseanswers were studied to give the individuals perspective, as well as allowing for the study of thephenomena by reviewing multiple perspectives to distinguish patterns. The results indicate thatcaring for a character takes longer if the player is not allowed to customize it. It was also indicated that the actual customization was more important than the character created.
366

A power line risk assessment for selected South African birds of conservation concern

Smallie, Jonathan James 18 January 2012 (has links)
MSc., Faculty of Science, University of the Witwatersrand, 2011 / A selection of southern African bird species were modelled in terms of the probability of these species colliding with or being electrocuted on overhead power lines in South Africa, based on morphological and behavioral factors. Species were included in the model on the basis of internationally recognized vulnerability to these interactions at the family level. The collision model performed poorly when tested against the actual reported mortalities for species contained in the Eskom-EWT Strategic Partnership Central Incident Register CIR)(chi-square of goodness of fit) at the individual species, family and within family levels. The electrocution model performed slightly better at the family, and within family level. Both collision and electrocution models performed better for the physically larger species (and families) and for those species with higher modelled probability of collision or electrocution. As the product of random carcass detection and reporting, the CIR data are biased in various ways. Testing the models against the CIR is therefore equally important for highlighting inadequacies in the CIR, as in the model. A number of new species have emerged as being of high collision (including most importantly African Pygmy Goose, Southern Ground Hornbill, Black-bellied Bustard, Yellow-throated Sandgrouse, Caspian Tern, Hooded Vulture, Bateleur, African Marsh Harrier, Black Harrier, Pink-backed Pelican and Yellow-billed Stork) or electrocution (Southern Bald Ibis) probability in theoretical terms, and will require further investigation to determine their actual probability of interaction. By mapping the combined distributions of those species with high probabilities of collision and/or electrocution mortality, a number of priority high risk geographic areas emerge around the country.
367

Rapid screening for antimicrobial genes in novel nocardiophages

Shibayama, Youtaro 08 December 2008 (has links)
There has been an increase in number of human infections by mycobacteria and opportunistic pathogens of the closely related nocardioform bacteria. Frequent multiple drug resistance in these organisms makes it desirable to identify novel targets for antimicrobial agents. Bacteriophages offer one way to do this as analysis of their DNA reveals great diversity in their genetic makeup, suggesting variety in the way they interfere with host cells. Four novel nocardiophages were therefore isolated from soil and characterized. Libraries of their nucleic acid were constructed and screened for clones inhibitory to a nocardioform of the genus Rhodococcus. Nine clones were characterized, and minimum necessary DNA for inhibitory activity sequenced. Of 18 ORFs predicted on these DNAs, 13 could not be assigned a function. Genes similar to ones in databases apparently interfered with DNA metabolism, protein synthesis, or integrity of plasma membrane. This genetic approach may be an efficient and effective way to discover novel targets for antibiotics.
368

Implementation of a VANET Geo-Fence Based Adaptive Traffic Light Control Scheme

Unknown Date (has links)
In this thesis we extend the VANET-based approach to counting vehicles at a traffic light by implementing a Geo-fence Based Vehicle Counting Algorithm which supports the use of RFID technology. This implementation utilizes the concept of geo-fencing to create a Zone of Interest (ZOI) that sections off a roadway that is relevant to a traffic intersection. All vehicles in this ZOI are used to determine the required length of the green-cycle time. By utilizing vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) technologies, we broadcast beacons that are propagated to all vehicles in the ZOI from the infrastructure which in this case is the traffic light controller. These beacons are used to determine the last vehicle location in the ZOI. A timing algorithm ensures that the last vehicle broadcasts first. The beacons are sent using the IEEE 1609.4 Wireless Access in Vehicular Environments Standard Vendor Specific Action (VSA) frames on the Smart Drive Initiative Vehiclular Ad Hoc Networks testbed. This work is implemented in conjunction with the Vehicular Multi-technology Communication Device (VMCD) supported by the National Science Foundation. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
369

Integrated system identification/control design with frequency weightings.

January 1995 (has links)
by Ka-lun Tung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 168-[175]). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Control with Uncertainties --- p.1 / Chapter 1.1.1 --- Adaptive Control --- p.2 / Chapter 1.1.2 --- H∞ Robust Control --- p.3 / Chapter 1.2 --- A Unified Framework: Adaptive Robust Control --- p.4 / Chapter 1.3 --- System Identification for Robust Control --- p.6 / Chapter 1.3.1 --- Choice of input signal --- p.7 / Chapter 1.4 --- Objectives and Contributions --- p.8 / Chapter 1.5 --- Thesis Outline --- p.9 / Chapter 2 --- Background on Robust Control --- p.11 / Chapter 2.1 --- Notation and Terminology --- p.12 / Chapter 2.1.1 --- Notation --- p.12 / Chapter 2.1.2 --- Linear System Terminology --- p.13 / Chapter 2.1.3 --- Norms --- p.15 / Chapter 2.1.4 --- More Terminology: A Standard Feedback Configuration --- p.17 / Chapter 2.2 --- Norms and Power for Signals and Systems --- p.18 / Chapter 2.3 --- Plant Uncertainty Model --- p.20 / Chapter 2.3.1 --- Multiplicative Unstructured Uncertainty --- p.21 / Chapter 2.3.2 --- Additive Unstructured Uncertainty --- p.22 / Chapter 2.3.3 --- Structured Uncertainty --- p.23 / Chapter 2.4 --- Motivation for H∞ Control Design --- p.23 / Chapter 2.4.1 --- Robust stabilization: Multiplicative Uncertainty and Weight- ing function W3 --- p.24 / Chapter 2.4.2 --- Robust stabilization: Additive Uncertainty and Weighting function W2 --- p.25 / Chapter 2.4.3 --- Tracking Problem --- p.26 / Chapter 2.4.4 --- Disturbance Rejection (or Sensitivity Minimization) --- p.27 / Chapter 2.5 --- The Robust Control Problem Statement --- p.28 / Chapter 2.5.1 --- The Mixed-Sensitivity Approach --- p.29 / Chapter 2.6 --- An Augmented Generalized Plant --- p.30 / Chapter 2.6.1 --- The Augmented Plant --- p.30 / Chapter 2.6.2 --- Adaptation of Augmented Plant to Sensitivity Minimiza- tion Problem --- p.32 / Chapter 2.6.3 --- Adaptation of Augmented Plant to Mixed-Sensitivity Prob- lem --- p.33 / Chapter 2.7 --- Using MATLAB Robust Control Toolbox --- p.34 / Chapter 3 --- Statistical Plant Set Estimation for Robust Control --- p.36 / Chapter 3.1 --- An Overview --- p.37 / Chapter 3.2 --- The Schroeder-phased Input Design --- p.39 / Chapter 3.3 --- The Statistical Additive Uncertainty Bounds --- p.40 / Chapter 3.4 --- Additive Uncertainty Characterization --- p.45 / Chapter 3.4.1 --- "Linear Programming Spectral Overbounding and Factor- ization Algorithm (LPSOF) [20,21]" --- p.45 / Chapter 4 --- Basic System Identification and Model Reduction Algorithms --- p.48 / Chapter 4.1 --- The Eigensystem Realization Algorithm --- p.49 / Chapter 4.1.1 --- Basic Algorithm --- p.49 / Chapter 4.1.2 --- Estimating Markov Parameters from Input/Output data: Observer/Kalman Filter Identification (OKID) --- p.51 / Chapter 4.2 --- The Frequency-Domain Identification via 2-norm Minimization --- p.54 / Chapter 4.3 --- Balanced Realization and Truncation --- p.55 / Chapter 4.4 --- Frequency Weighted Balanced Truncation --- p.56 / Chapter 5 --- Plant Model Reduction and Robust Control Design --- p.59 / Chapter 5.1 --- Problem Formulation --- p.59 / Chapter 5.2 --- Iterative Reweighting Scheme --- p.60 / Chapter 5.2.1 --- Rationale Behind the Scheme --- p.62 / Chapter 5.3 --- Integrated Model Reduction/ Robust Control Design with Iter- ated Reweighting --- p.63 / Chapter 5.4 --- A Design Example --- p.64 / Chapter 5.4.1 --- The Plant and Specification --- p.64 / Chapter 5.4.2 --- First Iteration --- p.65 / Chapter 5.4.3 --- Second Iteration --- p.67 / Chapter 5.5 --- Approximate Fractional Frequency Weighting --- p.69 / Chapter 5.5.1 --- Summary of Past Results --- p.69 / Chapter 5.5.2 --- Approximate Fractional Frequency Weighting Approach [40] --- p.70 / Chapter 5.5.3 --- Simulation Results --- p.71 / Chapter 5.6 --- Integrated System Identification/Control Design with Iterative Reweighting Scheme --- p.74 / Chapter 6 --- Controller Reduction and Robust Control Design --- p.82 / Chapter 6.1 --- Motivation for Controller Reduction --- p.83 / Chapter 6.2 --- Choice of Frequency Weightings for Controller Reduction --- p.84 / Chapter 6.2.1 --- Stability Margin Considerations --- p.84 / Chapter 6.2.2 --- Closed-Loop Transfer Function Considerations --- p.85 / Chapter 6.2.3 --- A New Way to Determine Frequency Weighting --- p.86 / Chapter 6.3 --- A Scheme for Iterative Frequency Weighted Controller Reduction (IFWCR) --- p.87 / Chapter 7 --- A Comparative Design Example --- p.90 / Chapter 7.1 --- Plant Model Reduction Approach --- p.90 / Chapter 7.2 --- Weighted Controller Reduction Approach --- p.94 / Chapter 7.2.1 --- A Full Order Controller --- p.94 / Chapter 7.2.2 --- Weighted Controller Reduction with Stability Considera- tions --- p.94 / Chapter 7.2.3 --- Iterative Weighted Controller Reduction --- p.96 / Chapter 7.3 --- Summary of Results --- p.101 / Chapter 7.4 --- Discussions of Results --- p.101 / Chapter 8 --- A Comparative Example on a Benchmark problem --- p.105 / Chapter 8.1 --- The Benchmark plant [54] --- p.106 / Chapter 8.1.1 --- Benchmark Format and Design Information --- p.106 / Chapter 8.1.2 --- Control Design Specifications --- p.107 / Chapter 8.2 --- Selection of Performance Weighting function --- p.108 / Chapter 8.2.1 --- Reciprocal Principle --- p.109 / Chapter 8.2.2 --- Selection of W1 --- p.110 / Chapter 8.2.3 --- Selection of W2 --- p.110 / Chapter 8.3 --- System Identification by ERA --- p.112 / Chapter 8.4 --- System Identification by Curve Fitting --- p.114 / Chapter 8.4.1 --- Spectral Estimate --- p.114 / Chapter 8.4.2 --- Curve Fitting Results --- p.114 / Chapter 8.5 --- Robust Control Design --- p.115 / Chapter 8.5.1 --- The selection of W1 weighting function --- p.115 / Chapter 8.5.2 --- Summary of Design Results --- p.116 / Chapter 8.6 --- Stress Level 1 --- p.117 / Chapter 8.6.1 --- System Identification Results --- p.117 / Chapter 8.6.2 --- Design Results --- p.119 / Chapter 8.6.3 --- Step Response --- p.121 / Chapter 8.7 --- Stress Level 2 --- p.124 / Chapter 8.7.1 --- System Identification Results --- p.124 / Chapter 8.7.2 --- Step Response --- p.125 / Chapter 8.8 --- Stress Level 3 --- p.128 / Chapter 8.8.1 --- System Identification Results --- p.128 / Chapter 8.8.2 --- Step Response --- p.129 / Chapter 8.9 --- Comparisons with Other Designs --- p.132 / Chapter 9 --- Conclusions and Recommendations for Further Research --- p.133 / Chapter 9.1 --- Conclusions --- p.133 / Chapter 9.2 --- Recommendations for Further Research --- p.135 / Chapter A --- Design Results of Stress Levels 2 and3 --- p.137 / Chapter A.1 --- Stress Level 2 --- p.137 / Chapter A.2 --- Stress Level 3 --- p.140 / Chapter B --- Step Responses with Reduced Order Controller --- p.142 / Chapter C --- Summary of Results of Other Groups on the Benchmark Prob- lem --- p.145 / Chapter C.1 --- Indirect and implicit adaptive predictive control [45] --- p.146 / Chapter C.2 --- H∞ Robust Control [51] --- p.150 / Chapter C.3 --- Robust Stability Degree Assignment [53] --- p.152 / Chapter C.4 --- Model Reference Adaptive Control [46] --- p.154 / Chapter C.5 --- Robust Pole Placement using ACSYDE (Automatic Control Sys- tem Design) [47] --- p.156 / Chapter C.6 --- Adaptive PI Control [48] --- p.157 / Chapter C.7 --- Adaptive Control with supervision [49] --- p.160 / Chapter C.8 --- Partial State Model Reference (PSRM) Control [50] --- p.162 / Chapter C.9 --- Contstrainted Receding Horizon Predictive Control (CRHPC) [52] --- p.165 / Bibliography --- p.168
370

Identification of rigid industrial robots - A system identification perspective / Identification de robots industriels rigides – Apport des méthodes de l’identification de systèmes

Brunot, Mathieu 30 November 2017 (has links)
L’industrie moderne fait largement appel à des robots industriels afin de réduire les coûts, ou encore améliorer la productivité et la qualité par exemple. Pour ce faire, une haute précision et une grande vitesse sont simultanément nécessaires. La conception de lois de commande conformes à de telles exigences demande une modélisation mathématique précise de ces robots. A cette fin, des modèles dynamiques sont construits à partir de données expérimentales. L’objectif de cette thèse est ainsi de fournir aux ingénieurs roboticiens des outils automatiques pour l’identification de bras robotiques. Dans cette perspective, une analyse comparative des méthodes existantes pour l’identification de robot est réalisée. Les avantages et inconvénients de chaque méthode sont ainsi mis en exergue. À partir de ces observations, les contributions sont articulées selon trois axes. Premièrement, l’étude porte sur l’estimation des vitesses et accélérations des corps du robot à partir de la position mesurée. Ces informations sont en effet nécessaires à la construction du modèle. La méthode usuelle est basée sur prétraitement "sur mesure" qui requière une connaissance fiable des bande-passantes du système, alors que celui-ci est encore inconnu. Pour surmonter ce dilemme, nous proposons une méthode capable d’estimer les dérivées automatiquement sans réglage préalable par l’utilisateur. Le deuxième axe concerne l’identification du contrôleur. Sa connaissance est en effet requise par la grande majorité des méthodes d’identification. Malheureusement, pour des raisons de propriété industrielle, il n’est pas toujours accessible. Pour traiter ce problème, deux méthodes sont introduites. Leur principe de base est d’identifier la loi de commande dans un premier temps avant d’identifier le modèle dynamique du bras robotique dans un second temps. La première méthode consiste à identifier la loi de commande de manière paramétrique, alors que la seconde fait appel à une identification non-paramétrique. Finalement, le troisième axe porte sur le réglage "sur mesure" du filtre decimate. L’identification du filtre de bruit est introduite en s’inspirant des méthodes développées par la communauté d’identification de systèmes. Ceci permet l’estimation automatique des paramètres dynamiques avec de faibles covariances tout en apportant une connaissance concernant la circulation du bruit à travers le système en boucle-fermée. Toutes les méthodes proposées sont validées sur un robot industriel à six degrés de liberté. Des perspectives sont esquissées pour de futurs travaux portant sur l’identification de systèmes robotiques, voire d’autres applications. / In modern manufacturing, industrial robots are essential components that allow saving cost, increase quality and productivity for instance. To achieve such goals, high accuracy and speed are simultaneously required. The design of control laws compliant with such requirements demands high-fidelity mathematical models of those robots. For this purpose, dynamic models are built from experimental data. The main objective of this thesis is thus to provide robotic engineers with automatic tools for identifying dynamic models of industrial robot arms. To achieve this aim, a comparative analysis of the existing methods dealing with robot identification is made. That allows discerning the advantages and the limitations of each method. From those observations, contributions are presented on three axes. First, the study focuses on the estimation of the joint velocities and accelerations from the measured position, which is required for the model construction. The usual method is based on a home-made prefiltering process that needs a reliable knowledge of the system’s bandwidths, whereas the system is still unknown. To overcome this dilemma, we propose a method able to estimate the joint derivatives automatically, without any setting from the user. The second axis is dedicated to the identification of the controller. For the vast majority of the method its knowledge is indeed required. Unfortunately, for copyright reasons, that is not always available to the user. To deal with this issue, two methods are suggested. Their basic philosophy is to identify the control law in a first step before identifying the dynamic model of the robot in a second one. The first method consists in identifying the control law in a parametric way, whereas the second one relies on a non-parametric identification. Finally, the third axis deals with the home-made setting of the decimate filter. The identification of the noise filter is introduced similarly to methods developed in the system identification community. This allows estimating automatically the dynamic parameters with low covariance and it brings some information about the noise circulation through the closed-loop system. All the proposed methodologies are validated on an industrial robot with 6 degrees of freedom. Perspectives are outlined for future developments on robotic systems identification and other complex problems.

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