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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.
91

ScreenCrayons: Using Screen Captures for Annotation and Research

Taufer, Trent Alan 16 December 2006 (has links) (PDF)
In a world full of digital information we should be able to easily collect, organize, annotate, and leverage information from many different sources. This should be easy to do and not interrupt our normal workflow. A system to support information collection and organization should be user-friendly and as unobtrusive as possible, while still allowing for flexible and intelligent annotation. It should also be able to leverage the inherent information content of a collection of annotated information. We present a system that will demonstrate how these ideas can come together to make information collection easier and more productive. The system facilitates collection, organization, and annotation of information using screen captures, and leverages the information content of the annotated collection to automatically summarize the information and find additional related information via searchable document repositories. ScreenCrayons is a system for collecting annotations on any type of document or visual information from any application. The basis for the system is a screen capture upon which the user can highlight the relevant portions of the image. The user can define any number of topics for organizing notes. Each topic is associated with a highlighting "crayon." In addition the user can supply annotations in digital ink or text. Algorithms are described that summarize captured images based on the highlight strokes so as to provide overviews of many annotations as well as being able to "zoom in" on particular information about a given note and the context of that note. Annotations the user makes on the screen captures are automatically associated with regions of text that are then used to formulate queries to a search engine. The results of these queries are filtered and ranked based on their similarity to the original annotations. The system then presents links to these documents to the user. We also describe an experiment that shows that the documents found by the annotation system are generally found to be more relevant to a user's topic than the users own queries using the search engine.
92

The Effect of Stretch Wrap Pre-stretch on Unitized Load Containment

Cernokus, Evan A 01 August 2012 (has links) (PDF)
There are three main factors affecting the stability of a palletized load that is unitized by a stretch wrapping mechanism. These factors include the type of unitized load, wrapping configuration and shipping method. The wrapping configuration is determined on the basis of the type of unitized load and shipping method. For this study, the aforementioned components were referred to as the package, the product, and the distribution environment. These components come together to make up a stretch wrapping system. The package corresponds to the stretch wrap film that is packaging the unitized load and pallet. The product corresponds to the goods placed on the pallet to be packaged by the stretch wrapper. The distribution environment corresponds to the hazards that the packaged product will encounter in transit. This study was designed to observe and understand the interactions between each of the components of the stretch wrap system. Prior to stretch wrapping a pallet of product, the film is elongated or pre-stretched. The elastic nature of the stretch wrap forces the film to conform around the palletized load. It is hypothesized that the film force that the stretch wrap applies to the palletized load contributes to improved load containment. Hence, the objective of this study was to determine the existence of a correlation between percentage pre-stretch to change in film force and load containment. For the study, a range of pre-stretched unitized loads were subjected to ISTA 3E distribution testing. Simultaneously the film force was monitored during the period of distribution testing. Subsequent to distribution testing, the load dispersion was quantified. The data obtained from this test suggested that there is no correlation between percentage pre-stretch and change in film force or load containment. The study also compared three methods of calculating pre-stretch: the marking wheel procedure, tapeless measure, and film cut and weigh. It was found that the most consistent method was the marking wheel procedure, followed by the cut and weigh procedure, and the tapeless measure procedure.
93

An Analysis of Commuting Distance and its Controlling Factors in the GTHA

Yawar, Sadia January 2016 (has links)
The increasing length of the daily commute is a major issue for many commuters in the Greater Toronto and Hamilton Area (GTHA). In order to alleviate this problem through policy, the policy makers require more in-depth understanding of this issue. This study explores different travel behaviour, socioeconomic and labour market determinants of commuting distance for resident workers in the GTHA, especially those having normal commutes and those having extreme commutes. This study also explores which areas of the GTHA are most self-contained, and what are the average commuting distances of each sub-region of the GTHA. The primary data source for this study was Transportation Tomorrow Survey (TTS) for the year 2011. Supplementary data were obtained from InfoCanada and Statistics Canada. Descriptive analysis in this study, focused at the Census Sub-Division (CSD), examined self-containment, outbound commutes, inbound commutes, resident employees and jobs densities, and average commute distances for place of residence and place of work. Study results showed that Toronto and Hamilton CSDs are the most self-contained areas in the GTHA, whereas areas located in the north and northwest of Toronto are major sources of outgoing commutes. Toronto and its adjacent CSDs have the lowest average commuting distance, whereas residents of Georgina and Brock commute exceptionally long distances. Multivariate regression analyses were applied to a disaggregate dataset (TTS). Workers older than 15 years of age living in the GTHA were divided into two major categories based on the length of their commute: (i) normal commuters (those having a mean commuting distance of 10.8 km) and (ii) extreme commuters (those having a mean commuting distance of 40.9 km). Factors affecting commuting distance for these two groups were examined. Similarly, residents living and working in the GTHA were divided into two categories: Resident workers living in (i) Jobs-rich areas or (ii) Resident-rich areas. Factors affecting commuting distance of these resident workers were also examined. The key controlling factors of commuting distance include gender, age, mode of transportation, employment status, ratio of jobs to employed residents, age of youngest child, auto availability in household, multi-worker household, median income, jobs and population density, and distance from CBD. Significant socioeconomic, travel behaviour and land use determinants for normal commute distances were also applicable to extreme commute distance. Transit was the preferred mode of transportation for long distance commuters in the GTHA, except for those living in job-rich areas. Workers associated with Sales and Service occupation and living in jobs-rich areas exhibited shorter commute than those in General/Clerical occupation. These findings are important to understand the changing travel patterns and behaviours of commuters in the GTHA. These results will be of interest to transportation planners, engineers, and policy makers as it highlights the inclination of long distance commuters to use transit. / Thesis / Master of Science (MSc)
94

Algebraic Trait for Structurally Balanced Property of Node and Its Applications in System Behaviors

Du, Wen (Electrical engineering researcher) 12 1900 (has links)
This thesis targets at providing an algebraic method to indicate network behaviors. Furthermore, for a signed-average consensus problem of the system behaviors, event-triggering signed-average algorithms are designed to reduce the communication overheads. In Chapter 1, the background is introduced, and the problem is formulated. In Chapter 2, notations and basics of graph theory are presented. It is known that the terminal value of the system state is determined by the initial state, left eigenvector and right eigenvector associated with zero eigenvalue of the Laplacian matrix. Since there is no mathematical expression of right eigenvector, in Chapter 3, mathematical expression of right eigenvector is given. In Chapter 4, algebraic trait for structurally balanced property of a node is proposed. In Chapter 5, a method for characterization of collective behaviors under directed signed networks is developed. In Chapter 6, dynamic event-triggering signed-average algorithms are proposed and proved for the purpose of relieving the communication burden between agents. Chapter 7 summarizes the thesis and gives future directions.
95

Assessing Urban Containment Policies for Managing the Urban Growth of Santa Tecla City, El Salvador

Mojica Bonilla, Ana I. January 2007 (has links)
No description available.
96

Impacts of urban containment policies on urban growth and structure

Woo, Myungje 10 December 2007 (has links)
No description available.
97

Correlation of the Elastic Properties of Stretch Film on Unit Load Containment

Bisha, James Victor 26 July 2012 (has links)
The purpose of this research was to correlate the applied material properties of stretch film with its elastic properties measured in a laboratory setting. There are currently no tools available for a packaging engineer to make a scientific decision on how one stretch film performs against another without applying the film. The system for stretch wrap comparison is mostly based on trial and error which can lead to a significant loss of product when testing a new film or shipping a new product for the first time. If the properties of applied stretch film could be predicted using a tensile test method, many different films could be compared at once without actually applying the film, saving time and money and reducing risk. The current method for evaluating the tensile properties of stretch film advises the user apply a hysteresis test to a standard sample size and calculate several standard engineering values. This test does not represent how the material is actually used. Therefore, a new tensile testing method was developed that considers the film gauge (thickness) and its prestretch. The results of this testing method allowed for the calculation of the material stiffness (Bisha Stiffness) and were used to predict its performance in unit load containment. Applied stretch film is currently compared measuring containment force, which current standards define as the amount of force required to pull out a 15.2cm diameter plate, 10.1cm out, located 25.4cm down from the top and 45.7cm over from the side of a standard 121.9cm width unit load. Given this definition, increasing the amount of force required to pull the plate out can be achieved by manipulating two different stretch film properties, either increasing the stiffness of the film or increasing the tension of the film across the face of the unit load during the application process. Therefore, for this research, the traditional definition of containment force has been broken down into two components. Applied film stiffness was defined as the amount of force required to pull the film a given distance off the unit load. Containment force was defined as the amount of force that an applied film exerts on the corner of the unit load. The applied stretch film was evaluated using two different methods. The first method used the standard 10.1cm pull plate (same plate as ASTM D 4649) to measure the force required to pull the film out at different increments from the center on the face of the unit load. This measurement force was transformed into a material stiffness and film tension (which were subsequently resolved into containment force). The second, newly developed, method involved wrapping a bar under the film, on the corner of the unit load, and pulling out on the bar with a tensile testing machine. This method allowed for the direct measurement of the containment force and material stiffness. The results indicated that while some statistically significant differences were found for certain films, the material stiffness and containment were relatively consistent and comparable using either method.The use of the Bisha Stiffness to predict the applied stiffness and containment force yielded a statistically significant correlation but with a very low coefficient of determination. These results suggest that while film thickness and prestretch are key variables that can predict applied stiffness and containment force, more research should be conducted to study other variables that may allow for a better. High variability of the predictions observed were caused by the differences in film morphology between the different method of elongation (tensile vs application). This study was the first that attempted to define and correlate the tensile properties of stretch film and the applied properties of stretch film. From this research many, terms have been clarified, myths have been dispelled, formulas have been properly derived and applied to the data collected and a clear path forward had been laid out for future researchers to be able to predict applied stiffness and containment force from the elastic properties of stretch film. / Ph. D.
98

Mécanismes de transfert aéraulique au travers d'ouvertures : application à l'efficacité du confinement dynamique d'enceintes de chantier / Aerodynamic transfer through openings : application to the efficiency of dynamic containment in site enclosures

Kaissoun, Salima 14 June 2018 (has links)
Les chantiers de maintenance et d’assainissement dans les centrales nucléaires nécessitent la mise en place d’enceintes ventilées autour des zones contaminées afin de limiter la propagation de la contamination à l’environnement extérieur. L’air rentre dans l’enceinte aux travers d’ouvertures sous la forme d’un écoulement directionnel, orienté de l’extérieur vers l’intérieur, assurant ainsi le confinement dynamique. En raison des opérations qui se déroulent à l’intérieur de l’enceinte et des perturbations externes, il est possible que l’écoulement de confinement dynamique aux ouvertures soit perturbé et subisse des inversions locales et instationnaires, conduisant ainsi à transporter la contamination à l’extérieur de l’enceinte. La présente étude s’intéresse aux petites ouvertures de type fentes minces rectangulaires où l’écoulement au droit de celles-ci est généralement turbulent. Les principaux objectifs de la thèse sont d’une part d’identifier les conditions aérodynamiques susceptibles de produire le phénomène de rétrodiffusion aux ouvertures, d’autre part d’évaluer la capacité des approches de modélisation de la turbulence URANS et LES à reproduire les instabilités liées à ce type d’écoulement. Il a été montré que l’apparition du phénomène de rétrodiffusion est principalement liée à la présence d’une perturbation aéraulique additionnelle, de type jet turbulent ou sillage, en compétition avec l’écoulement initial de confinement dynamique. Des expériences de traçage gazeux ont été mises en place sur une maquette expérimentale dans le but de quantifier la rétrodiffusion en fonction des différentes conditions aérauliques à l’ouverture et des caractéristiques de celle-ci. Des visualisations des écoulements à l’ouverture ont également été réalisées à l’aide d’un dispositif de tomographie laser. Enfin, l’analyse des résultats des simulations CFD a démontré que les approches de type RANS ou URANS ne permettaient pas de reproduire les instabilités de l’écoulement conduisant au phénomène de rétrodiffusion, contrairement aux simulations des grandes échelles de la turbulence (LES) qui reproduisent fidèlement les structures locales et instantanées à l’origine du phénomène. / Operations of decommissioning and decontamination in nuclear facilities require setting up depressurized enclosures around contaminated areas in order to prevent leakage of radioactive materials, to the surrounding environment. Air passes through openings which generates a directional airflow ensuring the aerodynamic containment of hazardous material inside the enclosure. Due to operating activities inside or outside the enclosure, the directional flow might be disturbed. Consequently, local and unsteady backflows may occur at the opening leading to the outward transport of contamination. The current study is focused on airflow dynamics through small openings, such as rectangular slits where the initial inflow stream is turbulent. The main purposes of this work are to identify the required aerodynamic conditions likely to generate unsteady flow inversions at the studied opening and also to verify the ability of CFD simulations to predict this type of flow by using URANS and LES approaches. Results have shown that an additional flow, such as a turbulent jet or a wake in competition with inward flow, is the main cause leading to the leakage at the opening. Experiments, using gas tracer detection techniques, are conducted in order to quantify outflow leakage in the near field of the opening under different aerodynamic configurations and openings characteristics. A laser tomography technique is also implemented to visualize the external leakage airflow in the middle plane of the opening. CFD simulations have shown that a qualitative description of instantaneous leakage flow patterns at the opening can be achieved. This is characterized by the occurrence of local coherent structures transporting passive tracer outwards. Moreover, velocities obtained from CFD results (Large Eddy Simulations) are compared to those obtained from experimental measurements.
99

Blockchain-based containment of computer worms

Elsayed, Mohamed Ahmed Seifeldin Mohamed 22 December 2020 (has links)
Information technology systems are essential for most businesses as they facilitate the handling and sharing of data and the execution of tasks. Due to connectivity to the internet and other internal networks, these systems are susceptible to cyberattacks. Computer worms are one of the most significant threats to computer systems because of their fast self-propagation to multiple systems and malicious payloads. Modern worms employ obfuscation techniques to avoid detection using patterns from previous attacks. Although the best defense is to eliminate (patch) the software vulnerabilities being exploited by computer worms, this requires a substantial amount of time to create, test, and deploy the patches. Worm containment techniques are used to reduce or stop the spread of worm infections to allow time for software patches to be developed and deployed. In this dissertation, a novel blockchain-based collaborative intrusion prevention system model is introduced. This model is designed to proactively contain zero-day and obfuscated computer worms. In this model, containment is achieved by creating and distributing signatures for the exploited vulnerabilities. Blockchain technology is employed to provide liveness, maintain an immutable record of vulnerability-based signatures to update peers, accomplish trust in confirming the occurrence of a malicious event and the corresponding signature, and allow a decentralized defensive environment. A consensus algorithm based on the Practical Byzantine Fault Tolerance (PBFT) algorithm is employed in the model. The TLA+ formal method is utilized to check the correctness, liveness, and safety properties of the model as well as to assert that it has no behavioral errors. A blockchain-based automatic worm containment system is implemented. A synthetic worm is created to exploit a network-deployed vulnerable program. This is used to evaluate the effectiveness of the containment system. It is shown that the system can contain the worm and has good performance. The system can contain 100 worm attacks a second by generating and distributing the corresponding vulnerability-based signatures. The system latency to contain these attacks is less than 10 ms. In addition, the system has low resource requirements with respect to memory, CPU, and network traffic. / Graduate
100

The Vietnam War debate and the Cold War consensus

Proctor, Patrick E. January 1900 (has links)
Doctor of Philosophy / Department of History / Donald Mrozek / Both Presidents Johnson and Nixon used the ideology of military containment of Communism to justify U.S. military intervention in Vietnam. Until 1968, opponents of this intervention attacked the ideology of containment or its application to Vietnam. In 1968, opponents of the war switched tactics and began to focus instead on the President’s credibility. These arguments quickly became the dominant critique of the war through its end and were ultimately successful in ending it. The Gulf of Tonkin incident and the Tonkin Gulf Resolution were central to the change of opposition strategy in 1968. For Johnson, the Gulf of Tonkin incident had provided the political impetus to pass the Tonkin Gulf Resolution, which the administration used as an insurance policy against Congressional dissent. For Congressional dissenters in 1968, inconsistencies in Johnson’s version of the Gulf of Tonkin incident allowed them to undermine the Resolution as a weapon against Congress. For the American people, revelations about the administration’s dishonesty during the incident simply added to grave doubts that Americans already had about Johnson’s credibility; the American people lost confidence in Johnson, ending his Presidency. The dramatic success of this new strategy—attacking the administration’s credibility—encouraged other opponents to follow suit, permanently altering the framework of debate over the war. This change in opposition strategy in 1968 had a number of important consequences. First, this change in rhetoric ultimately ended the war. To sustain his credibility against relentless attack, President Nixon repeatedly withdrew troops to prove to the American people he was ending the war. Nixon ran out of troops to withdraw and had to accept an unfavorable peace. Second, after the war, this framework for debate of military interventions established—between advocates using the ideology of containment and opponents attacking the administration’s credibility—would reemerge nearly every time an administration contemplated military intervention through the end of the Cold War. Finally, because opponents of military intervention stopped challenging containment in 1968, the American public continued to accept the precepts of containment and the Cold War consensus survived until the collapse of the Soviet Union and the end of the Cold War.

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