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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.
21

Residual Crashes and Injured Occupants with Lane Departure Prevention Systems

Riexinger, Luke E. 19 April 2021 (has links)
Every year, approximately 34,000 individuals are fatally injured in crashes on US roads [1]. These fatalities occur across many types of crash scenarios, each with its own causation factors. One way to prioritize research on a preventive technology is to compare the number of occupant fatalities relative to the total number of occupants involved in a crash scenario. Four crash modes are overrepresented among fatalities: single vehicle road departure crashes, control loss crashes, cross-centerline head-on crashes, and pedestrian/cyclist crashes [2]. Interestingly, three of these crash scenarios require the subject vehicle to depart from the initial lane of travel. Lane departure warning (LDW) systems track the vehicle lane position and can alert the driver through audible and haptic feedback before the vehicle crosses the lane line. Lane departure prevention (LDP) systems can perform an automatic steering maneuver to prevent the departure. Another method of prioritizing research is to determine factors common among the fatal crashes. In 2017, 30.4% of passenger vehicle crash fatalities involved a vehicle rollover [1]. Half of all fatal single vehicle road departure crashes resulted in a rollover yet only 12% of fatal multi-vehicle crashes involved a rollover [1]. These often occur after the driver has lost control of the vehicle and departed the road. Electronic stability control (ESC) can provide different braking to each wheel and allow the vehicle to maintain heading. While ESC is a promising technology, some rollover crashes still occur. Passive safety systems such as seat belts, side curtain airbags, and stronger roofs work to protect occupants during rollover crashes. Seat belts prevent occupants from moving inside the occupant compartment during the rollover and both seat belts and side curtain airbags can prevent occupants from being ejected from the vehicle. Stronger roofs ensure that the roof is not displaced during the rollover and the integrity of the occupant compartment is maintained to prevent occupant ejection. The focus of this dissertation is to evaluate the effectiveness of vehicle-based countermeasures, such as lane departure warning and electronic stability control, for preventing or mitigating single vehicle road departure crashes, cross-centerline head-on crashes, and single vehicle rollover crashes. This was accomplished by understanding how drivers respond to both road departure and cross-centerline events in real-world crashes. These driver models were used to simulate real crash scenarios with LDW/LDP systems to quantify their potential crash reduction. The residual crashes, which are not avoided with LDW/LDP systems or ESC, were analyzed to estimate the occupant injury outcome. For rollover crashes, a novel injury model was constructed that includes modern passive safety countermeasures such as seat belts, side curtain airbags, and stronger roofs. The results for road departure, head-on, and control loss rollover crashes were used to predict the number of crashes and injured occupants in the future. This work is important for identifying the residual crashes that require further research to reduce the number of injured crash occupants. / Doctor of Philosophy / Every year in the US, approximately 34,000 individuals are fatally injured in many different types of crashes. However, some crash types are more dangerous than other crash types. Drift-out-of-lane (DrOOL) road departure crashes, control loss road departure crashes, head-on crashes, and pedestrian crashes are more likely to result in an occupant fatality than other crash modes. In three of these more dangerous crash types, the vehicle departs from the lane before the crash occurs. Lane departure warning (LDW) systems can detect when the vehicle is about to cross the lane line and notify the driver with beeping or vibrating the steering wheel. A different system, called lane departure prevention (LDP), can provide automatic steering to prevent the vehicle from leaving the lane or return lane. In control loss crashes, the vehicle's motion is in a different direction than the vehicle's heading. During control loss, it is easier for the vehicle to roll over which is very dangerous. Electronic stability control (ESC) can prevent control loss by applying selective braking to each tire to keep the vehicle's motion in the same direction as the vehicle's heading. If a rollover still occurs, vehicles are equipped with passive safety systems and designs such as seat belts, side curtain airbags, and stronger roofs to protect the people inside. Seat belts can prevent occupants from striking the vehicle interior during the rollover and both seat belts and side curtain airbags can prevent occupants from being ejected from the vehicle. Stronger roofs ensure that the roof is not displaced during the rollover to prevent occupants from being ejected from the vehicle. The focus of this dissertation is to estimate how many crashes LDW, LDP, and ESC systems could prevent. This was accomplished by understanding how drivers respond after leaving their lane in real crashes. Then, these real crash scenarios were simulated with an LDW or LDP system to estimate how many crashes were prevented. The occupants of residual crashes, which were not prevented by the simulated systems, were analyzed to estimate the number of occupants with at least one moderate injury. Understanding which crashes and injuries that were not prevented with this technology can be used to decide where future research should occur to prevent more fatalities in road departure, head-on and control loss crashes.
22

A model for the implementation of Hazard Analysis Critical Control Points (HACCP) in the white fish industry

Villet, William de Gouret 03 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Fish and shellfish are, with very few exceptions, generally considered safe. Food safety laws in many parts of the world are, however, requiring companies to implement programs such as Hazard Analysis Critical Control Point (HACCP) as a means of assuring food safety from harvest to consumption. In South Africa, fishing companies wishing to export products to countries such as the European Union (EU), the United Sates (US), et cetera have, over the past number of years, been required to implement HACCP. Various issues are, however at stake with regards to the successful implementation of HACCP and thus this study project is primarily focused on the application of the HACCP system to the white fish industry. The method of study involved consultation with various local authorities in order to highlight existing HACCP problems within the South African White Fish Industry. A literature survey was conducted to ascertain the requirements of various countries and international organisations and iii addition to gain an in-depth knowledge as to theworking requirements of HACCP. Prior to setting in place a HACCP system, the model reviews in detail the HACCP manual requirements and prerequisite programs required. The prerequisite programs are not limited to but include good manufacturing practices, operation and sanitation, pest control, traceability and recall procedures, customer complaint procedures, chemical control program and training. Process flow diagrams need to be developed and verified for each process and product. Once completed an analysis of the various biological, chemical and physical hazards that are likely to affect the safety of the product is conducted. The seven principles of HACCP are clarified together with how they may best be implemented and monitored, taking in to consideration the various parameters of each fish processing establishment. A brief introduction about the relationship between the HACCP system, ISO 9000 and total quality management (TOM) and the advantages and disadvantages of each system is included. The study project is completed with recommendations for further study in other food processing industries. Recommendations include, but are not limited to ensuring that current and new legislation be regularly monitored, HACCP models be developed for industries such as the shellfish industry, et cetera and that, where possible, harmonisation of the requirements be internationally agreed upon. / AFRIKAANSE OPSOMMING: Oor die algemeen word vis en skulpvis, met 'n paar uitsonderings, as veilig beskou. Internasionaal word daar deur die voedsel veiligheidswette vereis dat maatskappye aan 'n standaard naamlik HACCP ( Hazard Analysis Critical Control Point) voldoen wat verseker dat die voedsel vanaf sy oorspronklike bron tot en met by die verbruiker veilig is vir gebruik. In Suid Afrika, word oor die laaste aantal jare van alle vismaatskappye wat vis wil uitvoer na Europeuse lande of die Verenigde state, verwag om HACCP te implimenteer. Verskeie kwessies is op die spel met betrekking tot die suksesvolle implimentering van HACCP en daarom word hierdie projek gefokus op die suksesvolle implimenteering van die HACCP beginsel in die witvis bedryf. Vir die studie is plaaslike owerhede genader om vas te stel waar bestaande probleme met betrekking tot die witvis bedryf is. 'n Literatuur studie is uitgevoer om te bepaal wat die behoeftes is van verskillende lande en internationale instansies en ook om 'n indiepte kennis te bekom vir die funksionerings vereistes van HACCP. Die model beskryf volledig wat vereis word om 'n HACCP handleiding saam te stel en die voorvereiste programme wat benodig word alvorens 'n HACCP plan inwerking gestel kan word. Daar is geen beperkings ten opsigte van die voorvereiste programme nie maar dit sluit die volgende in: goeie vervaardigings praktyke, higiëne bestuur, plaagbeheer, identifiseering en produk ontrekking prosedure, verbruikersklagtes, chemikalië beheer en opleiding. Vir elke proses en produk moet daar 'n vloei diagram opgestel word. Daarna moet 'n ontleding gedoen word van alle moontlike biologiese, chemiese en fisiese gevare wat die veiligheid van 'n produk kan benadeel. Verder bespreek die studie die sewe beginsels van HACCP, die implimentering en monitering daarvan met inagneming van die uniekheid van elke prosesaanleg. 'n Kort oorsig oor die verwantskap tussen HACCP, ISO 9000 en "TQM ( Total Quality Management)" met elk se voor en nadele word ook bespreek. Die studie word afgesluit met aanbevellings vir verdere studies in die voedselprosesseringsindustrie, oor die monitering van huidige en toekomstige wetgewing, die ontwikkeling van HACCP modelle en harmonisering van internasionale en plaaslike vereistes soos ooreengekom.
23

[en] PROCESS OF INTEGRATION AND IMPLEMENTATION OF QUALITY MANAGEMENT SYSTEM, ENVIRONMENTAL MANAGEMENT SYSTEMS AND SECURITY AND OCCUPATIONAL HEALTH SYSTEMS / [pt] PROCESSO DE INTEGRAÇÃO E IMPLEMENTAÇÃO DE SISTEMAS DE GESTÃO DA QUALIDADE, DO MEIO-AMBIENTE E DE SEGURANÇA E SAÚDE OCUPACIONAL

ILZA MARIA FRANCO BELGA 28 September 2007 (has links)
[pt] Esta dissertação propõe um processo de integração e implantação dos sistemas de gestão da qualidade, meio-ambiente e segurança e saúde ocupacional, os quais, atualmente, operam de forma isolada numa empresa. O negócio da empresa em questão é a produção de gases industriais e pretende que o processo de integração considere a cultura da organização e os esforços movidos nesta direção. A metodologia utilizada para a integração da gestão dos sistemas já é de uso e conhecimento das organizações e da academia e foi selecionada conforme equipe experiente e designada para este propósito, partindo do princípio que não se optaria pela reestruturação e sim pela adequação dos sistemas já existentes. São ainda comentados os pontos fracos identificados no programa de implantação dos sistemas isolados e que deveriam ser considerados quando da integração dos mesmos, assim como as necessidades que direcionam a integração e a expectativa com relação a responsividade, abrangência, resultados coletados, além da mudança cultural promovida. A estratégia é considerada diferencial na decisão da integração dos sistemas e a metodologia Seis Sigma a ferramenta que possibilita a mensuração de custos e a implantação da filosofia da melhoria contínua na busca em exceder as expectativas do cliente. / [en] This dissertation proposes an integration process and the implementation of quality management systems, environmental and safety policies, and occupational health. These systems are presently operating separately in the company. The company´s core business is the production of industrial gases and its internal policies establish that the integration process should take into consideration the culture of the organization and also the efforts already taken to move in this direction. The methodology applied for the systems integration management is under knowledge domain and it is being used by organizations and by the academy. It was selected and adopted by a skilled team assigned for this purpose, and it was defined that, instead of restructuring, adjustments would be made to existing systems. There are also comments about weak points identified in the program of implementation of isolated systems that should be considered for the integration process, as well as the needs that drive the integration and expectations related to responsiveness, scope of work, collected results and also the outcome in terms of cultural change. The strategy is considered relevant when deciding for systems integration and for the methodology Six Sigma, which is the tool that allows costs measurement and the implementation of the philosophy of continuous improvement to exceed customer´s expectations.
24

The food health policy of Hong Kong SAR Government /

Lok, Wai-shing. January 2001 (has links)
Thesis (M.P.A.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 108-115).
25

The food health policy of Hong Kong SAR Government

Lok, Wai-shing. January 2001 (has links)
Thesis (M.P.A.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 108-115). Also available in print.
26

Determining and Evaluating Cost-Effective Food Safety Risk Reduction Strategies at Retail Meat Facilities

Lehrke, Linda January 2006 (has links)
In spite of the documented success of Pathogen Reduction and Hazard Analysis and Critical Control Points (PR/HACCP) at the processing level, farm-level and retail-level application is optional. Several factors impact the gap of food safety regulations from farm to fork. This thesis focuses on the retail level. At the retail level, pathogen survival and the associated ability to cause further disease to humans even after being subjected to certain processing and packaging conditions have varying implications on the probability of sickness or death. This issue also arises over the fact that, sometimes, appropriate handling and processing instructions are not properly followed by consumers. The primary goals of the project are to develop an optimal food safety intervention strategy that incorporates risk, cost, and the value of pathogen reduction with alternative control mechanism. We wish to evaluate incentives for PR/HACCP-like planning and adherence to best management practices that promote safe food production. These incentives will be evaluated for the retail level. In addition, we will develop optimal intervention strategies for ready-to-eat meats and poultry products that incorporate risk assessment, cost of intervention, and the value of risk reduction of alternative strategies for the farm-to-table continuum. The model adopted in this study is an expansion of the stochastic optimization model developed by Nganje, Kaitibie, and Sorin (2005) to include the optimal intervention strategy at the retail ( consumer) level. These components are simulated with firm-level microbial data at the processing and retail level using stochastic optimizer software. Stochastic dominance was also used to compare across the optimal strategies and determine if there is one clear choice that is preferred. This allowed us incorporate risk preferences of firms. The scenario method was used to determine what factors would likely affect the adoption of PR/HACCP at the retail level. Finally, this thesis provides firms and policymakers a direction for future options concerning risk mitigation strategies.
27

Analýza možností odvracení střetu osobního a drážního vozidla na železničním přejezdu / Analysis of Possible Crash Avoidance of Personal and Rail vehicles at Railroad Crossings

Glogar, Matěj January 2012 (has links)
Presented diploma thesis deals with problems connected with accidents at railroad crossings from the road and railway drivers´ perspectives. The theoretical part is particularly focused on the explanation of chosen regulations associated with railroad crossings, with their construction and technical design and also with ways and options of marking in connection with railroad crossing safety system. The paper mentions the most frequent causes why dangerous situations occur. These causes arise from the railway and road drivers´ personal experience, supplemented by statistics of accidents at railroad crossings for the previous periods. The practical part analyses the options for averting a collision on two particular railroad crossings. For this purpose, the railroad crossing secured by lights and the railroad crossing secured only by a warning cross were chosen. Here, with Virtual Crash programme support, the origin of the chosen crisis situations is simulated and later options of their averting are evaluated. Finally, proposals for increasing railroad crossings safety are formulated for both cases. The appendix consists of a list of legislative regulations dealing with railroad crossings, a driving record of the rail vehicle and its technical parameters and simulation programme´s outputs.
28

3D visibility emergency stop system for automated industrial environments: An OpenGL based solution

Damasioti, Evangelia January 2022 (has links)
The advent of industry 4.0 has not only brought innovation and automation with it but also new challenges. Automation in industrial settings is advancing at a rapid pace, thus making the modern industrial workplace all the more stimulating. Highly automated robots and machines work alongside humans in settings that seemed fictional some years ago. However, the shift to a smart industry has brought about certain safety concerns regarding whether the current safety systems can keep up with this ever-changing environment. Emergency stop buttons have long been the industry standard when it comes to classic safety precautions. Nevertheless, researchers examine several possibilities on how they can upgrade the already established safety systems. One such practice is to incorporate visibility as part of an emergency safety system. There has already been a proposal to use 2D visibility as an emergency safety protocol which has shown encouraging results. Thus, making a 3D approach as the logical next step. In this thesis work, a 3D visibility emergency stop system is presented, implemented,and tested. To begin with, a small review of how other researchers have tried to solve similar problems is done. Furthermore, several 3D graphics techniques used in the project are introduced and briefly analysed. Then, the implementation of the project is presented, breaking down each component. After the implementation is completed, several tests that aim to profile the program are performed and examined. In addition, the project is compared to the 2D solution that has already been proposed. The findings from the testing show that a 3D visibility approach is a viable and favourable option. The results reveal a promising outcome when it comes to object visibility as well as response swiftness.
29

Radar Target detection using Cell Evaluation Method for Industrial Safety

Sambath, Praanesh January 2020 (has links)
The main aim of using radars in industrial safety system is to detect the presence of target accurately. The conventional methods of radar target detection algorithm such as the Cell averaging constant false alarm rate method (CA-CFAR), Greatest of constant false alarm method (GO-CFAR) and the Smallest of constant false alarm rate method (SO-CFAR) has their own disadvantage when it comes to precise target detection which is a key factor for a safety system. This thesis investigates the above mentioned conventional CFAR algorithms for its pros and cons in target detection and proposes a new and improved method called Cell Evaluation target detection method. The proposed method is shown to mitigate the limitations present and the assumptions made in the conventional target detection method. Further more angular estimation is performed to determine the precise location of the target and the artifacts due to the angular estimation is eliminated by aggregating the detected points from multiple radar modules by linear translation. This gives a better visualization of the target. / Radarteknik kan användas inom maskinsäkerhet (MS) för att detektera skyddsvärda objekt, typiskt människor i arbete nära maskiner. Konventionella metoder för detektering med given frekvens falsk alarm (eng. Constant False Alarm Rate (CFAR)) som baseras på medelvärden, har dock betydande brister. Främst beträffande precision och tillförlitlighet, vilket är centralt för MS. Exempel som studerats i detta examensarbete är “Cell-averaging CFAR” (CA-CFAR), “Greatest of CFAR” (GO-CFAR) samt “Smallest of CFAR” (SO-CFAR). Med målet att förbättra detektionen föreslås även en ny CFAR-metod, vilken benämns ”Cell Evaluation target detection”. I detta arbete visas denna metod undertrycka begränsningar med konventionella tekniker. Den undviker även en del antaganden som inte alltid stämmer i praktiken. Studien inkluderar även skattning av riktning. Det visas hur visualisering av skyddsobjekt kan förbättras, genom att felaktigheter elimineras efter sammanläggning av detektioner från flera radarmoduler efter koordinattransformation.
30

UV Disinfection between Concentric Cylinders

Ye, Zhengcai 10 January 2007 (has links)
Outbreaks of food-born illness associated with the consumption of unpasteurized juice and apple cider have resulted in a rule published by the U.S. Food and Drug Administration (FDA) in order to improve the safety of juice products. The rule (21 CFR120) requires manufacturers of juice products to develop a Hazard Analysis and Critical Control Point (HACCP) plan and to achieve a 5-log reduction in the number of the most resistant pathogens. Ultraviolet (UV) disinfection is one of the promising methods to reach this 5-log reduction of pathogens. The absorption coefficients of juices typically vary from 10 to 40 1/cm and can be even higher depending on brand and processing conditions. Thin film reactors consisting of two concentric cylinders are suitable for inactivating pathogens in juices. When the two concentric cylinders are fixed, the flow pattern in the gap can be laminar Poiseuille flow or turbulent flow depending on flow rates. If the inner cylinder is rotating, and the rotating speed of the inner cylinder exceeds a certain value, the flow pattern can be either laminar or turbulent Taylor-Couette flow. UV disinfection between concentric cylinders in laminar Poiseuille flow, turbulent flow and both laminar and turbulent Taylor-Couette flow was investigated experimentally and numerically. This is the first systematic study done on UV disinfection between concentric cylinders in all three flow patterns. The present work provides new experimental data for pathogen inactivation in each of the three flow patterns. In addition, the present study constitutes the first systematic numerical CFD predictions of expected inactivation levels. Proper operating parameters and optimum gap widths for different flow patterns are suggested. It is concluded that laminar Poiseuille flow provides inferior (small) inactivation levels while laminar Taylor-Couette flow provides superior (large) inactivation levels. The relative inactivation levels are: laminar Poiseuille flow < turbulent flow < laminar Taylor-Couette flow.

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