Thesis (M.P.A.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 108-115).

Thesis (M.P.A.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 108-115). Also available in print.

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.

Förekomsten av extremväder på grund av klimatförändringar har med åren ökat vilket gjort att förekomsten av naturhändelser bedöms öka i framtiden. Vid krissituationer i samhället är det bra om det är planerat för trygghetspunkter som är platser dit människor kan ta sig vid kris. Kommuner har det yttersta ansvaret för krisberedskap i kommunen men kan även samarbeta med andra aktörer som till exempel trossamfund. Svenska kyrkan är ett sådant trossamfund som har vana av att hjälpa till vid kriser och som innehar ett fastighetsbestånd med byggnader över hela Sverige. Syftet med den här studien är att i Säffle, Åmåls och Melleruds pastorat utvärdera kyrkbyggnader inom Svenska kyrkans fastighetsbestånd som potentiella trygghetspunkter. Detta utifrån underkriterierna naturolyckor, energi och tillgänglighet samt huvudkriteriet trygghetspunkt. I Sverige är vegetationsbrand och översvämningar samt ras och skred bland de vanligast förekommande orsakerna till naturolyckor. Vid kriser som dessa kan orsaka kan trygghetspunkter som uppfyller vissa kriterier behöva finnas tillgängliga. Ett sätt att hitta optimala lösningar med hjälp av olika kriterier är att använda sig av en multikriterieanalys (MKA). Det finns flera olika metoder inom MKA och en av dessa är Analytical Hierarchy Process (AHP) som är en viktningsmetod. En annan MKA-metod är Weighted Linear Combination (WLC) och den implementerar MKA i geografiskt informationssystem (GIS).    Totalt utvärderades 50 kyrkbyggnader som lämpliga trygghetspunkter. Analyser för att ta fram viktningsattribut utfördes i ArcGIS Pro eller kontrollerades manuellt i kartor. MKA-metoderna AHP och WLC användes och resultatet visar att Säffle kyrka är den byggnad som är mest lämplig som trygghetspunkt under samtliga kriteriekategorier med undantag för energi där Åmåls församlingshem är lämpligast. Byggnader i examensarbetet har viktats mot varandra utifrån olika attribut och inte mot yttre variabler. Flera byggnader fick högt lämplighetsvärde i flera kriteriekategorier och många av dessa byggnader låg i närheten av orterna Säffle, Åmål och Mellerud. Möjligheten för fortsatta studier inom området trygghetspunkter är stor. / The occurrence of extreme weather events due to climate change has increased over the years, which has made the occurrence of natural disasters to be expected to increase in the future. When crisis occurs in society it is good if there are planned points of safety to where people can go. Municipalities have the ultimate responsibility for crisis management in the municipality, but they can also work together with other parts of society to achieve this, such as religious communities. The Church of Sweden is one such faith community that are used to helping in crises and that have buildings throughout Sweden.  The purpose of this study is to evaluate church buildings within the Church of Sweden's property holdings in the parishes of Säffle, Åmål and Mellerud as potential points of safety. The evaluation is based on the sub-criteria natural disasters, energy and accessibility, as well as the main criterion point of safety. In Sweden, vegetation fires, floods and landslides are among the most common causes of natural disasters. When crises caused  by these occurs, points of safety that meet certain criteria need to be available. One way to find optimal solutions using different criteria is to use Multi Criteria Evaluation (MCE). There are several different methods within MCE and one of them are AHP, which is a weighting method. Another MCE method is called Weighted Linear Combination (WLC) which is a method that implements MCE in Geographic Information System (GIS). A total of 50 church buildings were evaluated as potential points of safety in this study. Analyzes to obtain weighting attributes were performed in ArcGIS Pro or checked manually in maps. MCE methods AHP and WLC were used to bring out a result. The result shows that the Säffle kyrka was the most suitable building to become a point of safety in all criteria except for energy where Åmåls församlingshem received the highest value. Buildings in this study were weighted against each other based on their different attributes and not against outer variables. Several buildings received a high value within several criteria and many of these buildings were located near the towns of Säffle, Åmål and Mellerud. The opportunities for further studies regarding point of safety are great.

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.

published_or_final_version / Public Administration / Master / Master of Public Administration

Foodbome disease outbreaks have a tremendous impact on society, including foodbome illnesses, hospitalizations, lost work time, and deaths. These food-safety events have a significant influence in shaping consumers' perception of risk. Outbreaks of foodbome illnesses also have an effect on the development of public health policy. Due to these safety-related uncertainties in the food supply chain, various regulatory, safety, and health policies are implemented to decrease harm to potential victims. The total effect of such food-safety policies looked at in terms of reduction of foodbome illness, mortality, and food-related diseases may possibly be smaller than the forecasted effect because of failure to consider offsetting behavior. Attenuation and possibly reversal of the direct policy effect on expected injuries may arise because of offsetting behavior. This study combines both theoretical and empirical models to test the presence of dominant or partial offsetting behavior (OB) in the preparation and consumption of vegetables if a food-safety policy such as the Pathogen Reduction/Hazard Analysis and Critical Control Point (PR/HACCP) is mandated in the vegetable sector. Our findings indicate that food-safety information that has an effect on outrage and locus of control, both factors which have an effect on consumers' perception of risk, will lead consumers to become lax in response to this food-safety policy.