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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.
651

A Study of Accidents and Their Causes Occurring in Industrial Shops in the Public Schools of Texas, and the Methods Used to Teach Safety Education in Industrial Arts Program

Turner, Finis 08 1900 (has links)
The problem of this study is to determine sound practices and teaching in connection with Industrial Arts shop safety program in Texas public schools, and the methods, policies, and programs used to prevent accidents. The study reviews the Texas State Laws for safety precaution, and the devices and programs recommended by the Industrial Arts teachers who answered the questionnaire used in this study. The state safety laws of other states are studied for comparison with the Texas Safety Laws.
652

Determining the Safety of Urban Arterial Roads

Campbell, Meredith L 29 April 2004 (has links)
The purpose of this project was to investigate the safety of urban arterial non-access controlled roads in Worcester, Massachusetts. An investigation into the dependent variable proved inconclusive and the historical accident rate was used. The best functional form for these roads was unclear so both linear and log-linear models were developed. A linear model was developed that predicted the total accident crash rate and log-linear model was developed to predict the same thing. A second linear model was developed to predict the total injury accident crash rate. The models were validated using independent data where the linear total accident crash rate model was found to be the most robust of the three in that both state primary roads and other arterial roads could have crash rates predicted to a better than fifty percent error.
653

The knowledge, attitude and perception concerning occupational health and safety among staff in the technical division of the Turfloop campus, University of Limpopo

Mashamba, Takalani Joyce January 2005 (has links)
Thesis (MPH.) -- University of Limpopo, 2005 / Refer to document
654

A Comparative Analysis of Argumentation Languages in the Context of Safety Case Development

Govardhan Rao, Sirisha Bai January 2019 (has links)
The safety case creation has become an explicit requirement in most of the safety-critical domains to ensure the safety of a system or an application. In the process of developing a safety case, the foremost requirement is choosing an efficient argumentation language which fulfills all the functionalities needed to develop a safety case.   In general, there are text-based argumentation notations and graphics-based argumentation notations to represent a safety case. In this paper we are comparing and analyzing the graphics-based argumentation notations like Goal Structuring Notation (GSN), Claims Arguments and Evidence (CAE), Structured Assurance Case Metamodel (SACM, the standardized modelling language to describe the safety case), NOR-STA Services (software platform which support graphics-based notations), Resolute (which is both language and tool that supports graphics-based notations) and Dynamic Safety Cases (special type of safety case which supports graphics-based notations such as GSN).   In this thesis, we compared the argumentation notations with respect to different aspects in the context of safety case development. We present our findings like the types of stakeholders gaining benefits from different types of notations, the list of domains where these types of notations are applicable. We also presented the major advantages and disadvantages of using different argumentation notations considering certain features like understandability, standardization, consistency, maintenance, traceability, and assessment in the context of safety case development.
655

SEGMENTATION STRATEGIES FOR ROAD SAFETY ANALYSIS

Green, Eric R. 01 January 2018 (has links)
This dissertation addresses the relationship between roadway segment length and roadway attributes and their relationship to the efficacy of Safety Performance Function (SPF) models. This research focuses on three aspects of segmentation: segment length, roadway attributes, and combinations of the two. First, it is shown that choice of average roadway segment length can result in markedly different priority lists. This leads to an investigation of the effect of segment length on the development of SPFs and identifies average lengths that produce the best-fitting SPF. Secondly, roadway attributes are filtered to test the effect that homogeneity has on SPF development. Lastly, a combination of segment length and attributes are examined in the same context. In the process of conducting this research a tool was developed that provides objective goodness-of-fit measures as well as visual depictions of the model. This information can be used to avoid things like omitted variable bias by allowing the user to include other variables or filter the database. This dissertation also discusses and offers examples of ways to improve the models by employing alternate model forms. This research revealed that SPF development is sensitive to a variety of factors related to segment length and attributes. It is clear that strict base condition filters based on the most predominant roadway attributes provide the best models. The preferred functional form was shown to be dependent on the segmentation approach (fixed versus variable length). Overall, an important step in SPF development process is evaluation and comparison to determine the ideal length and attributes for the network being analyzed (about 2 miles or 3.2 km for Kentucky parkways). As such, a framework is provided to help safety professionals employ the findings from this research.
656

Temporary Restaurant Closures and Food Handling Violations: Inspection Reports in British Columbia

Mandarino, Pam 01 January 2017 (has links)
Unsafe food handling practices are implicated in many restaurant-associated foodborne disease outbreaks. Factors that contribute to unsafe food handling in restaurants include inadequate food safety knowledge, employees who perceive that safe food handling is not under their control, and restaurant cultures that do not prioritize food safety. The purpose of this study was to determine whether temporary restaurant closures were associated with reduced food handling violations after closure in restaurants from the Vancouver Coastal Health Authority and the Fraser Health Authority, in British Columbia, Canada. The theoretical foundations used were the health action process approach and the theory of planned behavior. Mixed-effects Poisson regression analyses showed that the typical restaurant had an estimated 16% increase in the average number of overall food handling violations per inspection after temporary closure, compared with before closure. Restaurant- and employee-related factors responsible for unsafe food handling practices likely result in the continuation of unsafe food handling practices, despite temporary restaurant closures. This study may contribute to positive social change by challenging the assumption that temporary restaurant closures motivate food handlers to improve their food handling practices. To protect the public's health, additional interventions must follow temporary restaurant closures for reasons such as insanitary conditions and improper food handling. Suggested interventions include the provision of targeted learning resources to restaurant managers, the issuing of directives requiring food handlers to attend recognized food safety training courses, and environmental health managers requiring a reduction in problematic menu items.
657

Rapid establishment of emergency action areas as a consequence of large scale radioactive material releases from fixed nuclear facilities

Fundak, Robert 15 March 1995 (has links)
Rapid emergency response decisions from a radiation release are necessary in order to prevent the general public from being exposed to a potential radiation hazard. A one meter exposure rate measurement is all that is necessary to establish relocation and food control areas when the ground is contaminated at the Protective Action Guide minimum response levels. With the results of these calculations, a known one meter exposure rate is all that is necessary to establish relocation and food control areas for a release from the WNP-2 commercial nuclear power plant or a release from a waste tank at the Hanford site. The calculated one meter exposure rate for WNP-2 is 1.32 ��R/hr at twenty-four hours. The calculated one meter exposure rate for the Hanford tanks is 14.97 ��R/hr. / Graduation date: 1995
658

Indicators for traffic safety assessment and prediction and their application in micro-simulation modelling : a study of urban and suburban intersections

Archer, Jeffery January 2005 (has links)
In order to achieve sustainable long-term transport infrastructure development, there is a growing need for fast, reliable and effective methods to evaluate and predict the impact of traffic safety measures. Recognising this need, and the need for an active traffic safety approach, this thesis focuses on traffic safety assessment and prediction based on the use of safety indicators that measure the spatial and/or temporal proximity of safety critical events. The main advantage of such measures is that they occur more frequently than accidents, and therefore require relatively short periods of study to establish values that can later be used for comparison, or for accident prediction purposes. There are a number of more generally accepted safety indicators including: Time-to-Accident, Time-to-Collision, and Post-Encroachment Time. These are based on different underlying principles and measurement techniques, including both on-site subjective estimation, and objective photometric measures. A major part of the work presented in this thesis, concerns identifying the potential and limitations of the different safety indicators with regard to their validity and reliability, and practical use for safety assessment and prediction purposes. This is done in conjunction with field studies in the urban and suburban environment, at both signalised and unsignalised intersections. Results from these studies indicate that on-site observation methods provide useful quantitative and qualitative information relatively quickly and efficiently, provided that they are used correctly. On the other hand, the methods based on photometric measurement (video-analysis) proved arduous and time-consuming. Furthermore, there are questions regarding the abilities of the Time-to-Collision and Post-Encroachment Time safety indicators to adequately represent interaction severity, suggesting possible flaws in fundamental concepts related to construct validity. Importantly, results showed that the relationship between safety indicators and traffic accidents is complex and equivocal, where many different factors and processes can impose a significant influence on safety. This makes generalised predictive modelling a particularly difficult task for safety analysts. The potential of micro-simulation for traffic safety and performance estimation based on the use of safety indicators was investigated in the second part of this thesis. Microscopic traffic simulation has become increasingly popular among transport planners, due to the fact that it serves as a safe and flexible off-line test environment for the estimation of dynamic and complex traffic system effects. It is useful and cost-effective in relation to the evaluation of issues concerning roadway design, and technological systems that influence road-user behaviour and vehicle performance. For reasons related to modelling fidelity and data quality, simulation has seldom been used for traffic safety estimation. Simulation model development is however, undergoing rapid development and the area of ‘safety-simulation’ and is recognised as having a high potential in the field of transport planning and traffic engineering. As part of the work in this thesis, practical simulation experiments were carried out to investigate this potential, and identify limitations. Based on the data from one of the earlier studies, and knowledge regarding important safety-influencing factors and behavioural processes, one of the simulation experiments showed evidence to suggest that realistic safety critical events could be generated and measured using safety indicators in a simulation environment, without making unnecessary and unrealistic behavioural assumptions. Furthermore, a second application of this methodology revealed the safety potential of a rear-end incident-reduction function used in standard vehicle actuated signalling. While both of these simulation studies highlighted the potential of this type of approach, the need for more flexible and realistic models of interactive behavioural processes could be identified in addition to the general need for greater active research into the field of safety simulation. / QC 20100830
659

Assessing Safety Performance of Transportation Systems using Microscopic Simulation

Cunto, Flávio January 2008 (has links)
Transportation safety has been recognized as a public health issue worldwide, consequently, transportation researchers and practitioners have been attempting to provide adequate safety performance for the various transportation components and facilities to all road users given the usually scarce resources available. Safety engineers have been trying to make decisions affecting safety based on the knowledge extracted from different types of statistical models and/or observational before-after analysis. It is generally recognized that this type of factual knowledge is not easily obtained either statistically or empirically. Despite the intuitive link between road safety and observed crashes, a good understanding of the sequence of events prior to the crash can provide a more rational basis for the development of engineering countermeasures. The development of more comprehensive mechanistic models for safety assessment is heavily dependent on detailed vehicle tracking data that is not readily available. The potential of microscopic simulation in traffic safety and traffic conflict analysis has gained increasing interest mostly due to recent developments in human behaviour modelling and real-time vehicle data acquisition. In this thesis, we present a systematic investigation of the use of existing behavioural microscopic simulation models in short-term road safety studies. Initially, a microscopic framework is introduced to identify potentially unsafe vehicle interactions for different vehicle movements based on three types of traffic behaviour protocols: car-following, lane change and gap acceptance. This microscopic model for safety assessment applies a safety performance measure based on pairwise comparisons of spacing and speed differential between adjacent vehicles and individual braking power in real-time. A calibration/validation procedure using factorial analysis is presented to select best model input parameters for this safety performance measure by using high resolution vehicle tracking data. The ability of the proposed safety performance measure to reflect real-life observed high-risk vehicular interactions is explored in three intuitive tests using observed crash data. Finally, the usefulness of the model is illustrated through its application to investigate the safety implications of two different geometric and operational traffic strategies. The overall results indicate that, notwithstanding the fact that actual behavioural microscopic algorithms have not been developed strictly to model crashes, they are able to replicate several factors directly related to high risk situations that could lead to crashes with reasonable accuracy. With the existing upward trend in computing power, modelling techniques and increasing availability of detailed vehicle tracking data, it is likely that safety studies will be carried out using a more mechanistic and inclusive approach based on disruptive driving behaviour rather than ultimate unpredictable and heavily restrictive crash events.
660

Assessing Safety Performance of Transportation Systems using Microscopic Simulation

Cunto, Flávio January 2008 (has links)
Transportation safety has been recognized as a public health issue worldwide, consequently, transportation researchers and practitioners have been attempting to provide adequate safety performance for the various transportation components and facilities to all road users given the usually scarce resources available. Safety engineers have been trying to make decisions affecting safety based on the knowledge extracted from different types of statistical models and/or observational before-after analysis. It is generally recognized that this type of factual knowledge is not easily obtained either statistically or empirically. Despite the intuitive link between road safety and observed crashes, a good understanding of the sequence of events prior to the crash can provide a more rational basis for the development of engineering countermeasures. The development of more comprehensive mechanistic models for safety assessment is heavily dependent on detailed vehicle tracking data that is not readily available. The potential of microscopic simulation in traffic safety and traffic conflict analysis has gained increasing interest mostly due to recent developments in human behaviour modelling and real-time vehicle data acquisition. In this thesis, we present a systematic investigation of the use of existing behavioural microscopic simulation models in short-term road safety studies. Initially, a microscopic framework is introduced to identify potentially unsafe vehicle interactions for different vehicle movements based on three types of traffic behaviour protocols: car-following, lane change and gap acceptance. This microscopic model for safety assessment applies a safety performance measure based on pairwise comparisons of spacing and speed differential between adjacent vehicles and individual braking power in real-time. A calibration/validation procedure using factorial analysis is presented to select best model input parameters for this safety performance measure by using high resolution vehicle tracking data. The ability of the proposed safety performance measure to reflect real-life observed high-risk vehicular interactions is explored in three intuitive tests using observed crash data. Finally, the usefulness of the model is illustrated through its application to investigate the safety implications of two different geometric and operational traffic strategies. The overall results indicate that, notwithstanding the fact that actual behavioural microscopic algorithms have not been developed strictly to model crashes, they are able to replicate several factors directly related to high risk situations that could lead to crashes with reasonable accuracy. With the existing upward trend in computing power, modelling techniques and increasing availability of detailed vehicle tracking data, it is likely that safety studies will be carried out using a more mechanistic and inclusive approach based on disruptive driving behaviour rather than ultimate unpredictable and heavily restrictive crash events.

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