Tesis sobre el tema "Safety and availability"

The increased demand for interoperability among Emergency Responders (ERs) and timely accessibility to a large amount of reliable, accurate, context and location aware, and privacy-preserved data (e.g., environmental data, health records, building plan, etc.), mandates the emergence of dedicated Public Safety Broadband Networks (PSBNs). However, realizing PSBNs and addressing such requirements encounters substantial challenges. For example, several security and privacy vulnerabilities have been detected in the Long Term Evolution (LTE) which is the leading enabler of PSBNs. Nonetheless, the more significant challenge lies under the corresponding data requirements. This is because data is unstructured, its volume is enormous, and it includes inaccurate, irrelevant, and context-free data. Moreover, the data sources are heterogeneous and may not be reachable in an emergency. Furthermore, the data contains personally identifiable information for which privacy and access authorization should be respected. In this thesis, we investigate and address the aforementioned challenges. Here, we propose an efficient and secure algorithm to mitigate the main security and privacy vulnerability of LTE. In addition, to provide context and location aware data availability during an emergency, we propose a secure data storage structure and privacy-preserving search scheme. Furthermore, we propose a location-aware data access model to filter irrelevant data with regards to an incident and prevent unauthorized data access. To envision our access model, we propose a location-aware fine grained access authorization scheme. Our security analysis shows that our search scheme is secure against a chosen keyword attack and the proposed authorization scheme is formally proven secure against a selective chosen ciphertext attack. Concerning performance efficiency, our search scheme requires minimal data search and retrieval delay and the proposed authorization scheme imposes constant communication and decryption computation overheads. Finally, we propose a context-aware framework, which fully complies with emergency response requirements, based on the concept of trust to filter-out inaccurate and irrelevant data. The integration of our contributions promises highly reliable, accurate, context and location aware, and privacy-preserved data availability and timely data accessibility.

STUDY QUESTION: What is the evidence pertaining to availability, effectiveness and safety of assisted reproductive technology (ART) in sub-Saharan Africa? SUMMARY ANSWER: According to overall limited and heterogeneous evidence, availability and utilization of ART are very low, clinical pregnancy rates largely compare to other regions but are accompanied by high multiple pregnancy rates, and in the near absence of data on deliveries and live births the true degree of effectiveness and safety remains to be established. WHAT IS KNOWN ALREADY: In most world regions, availability, utilization and outcomes of ART are monitored and reported by national and regional ART registries. In sub-Saharan Africa there is only one national and no regional registry to date, raising the question what other evidence exists documenting the status of ART in this region. STUDY DESIGN, SIZE, DURATION: A systematic review was conducted searching PUBMED, SCOPUS, AFRICAWIDE, WEB OF SCIENCE and CINAHL databases from January 2000 to June 2017. A total of 29 studies were included in the review. The extracted data were not suitable for meta-analysis. PARTICIPANTS/MATERIALS, SETTING, METHOD: The review was conducted according to PRISMA guidelines. All peer-reviewed manuscripts irrespective of language or study design that presented original data pertaining to availability, effectiveness and safety of ART in sub-Saharan Africa were eligible for inclusion. Selection criteria were specified prior to the search. Two authors independently reviewed studies for possible inclusion and critically appraised selected manuscripts. Data were analyzed descriptively, being unsuitable for statistical analysis. MAIN RESULTS AND THE ROLE OF CHANCE: The search yielded 810 references of which 29 were included based on the predefined selection and eligibility criteria. Extracted data came from 23 single centre observational studies, 2 global ART reports, 2 reviews, 1 national data registry and 1 community-based study. ART services were available in 10 countries and delivered by 80 centres in 6 of these. Data pertaining to number of procedures existed from 3 countries totalling 4619 fresh non-donor aspirations in 2010. The most prominent barrier to access was cost. Clinical pregnancy rates ranged between 21.2% to 43.9% per embryo transfer but information on deliveries and live births were lacking, seriously limiting evaluation of ART effectiveness. When documented, the rate of multiple pregnancy was high with information on outcomes similarly lacking. LIMITATIONS, REASONS FOR CAUTION: The findings in this review are based on limited data from a limited number of countries, and are derived from heterogeneous studies, both in terms of study design and quality, many of which include small sample sizes. Although representing best available evidence, this requires careful interpretation regarding the degree of representativeness of the current status of ART in sub-Saharan Africa. WIDER IMPLICATIONS OF THE FINDINGS: The true extent and outcome of ART in sub-Saharan Africa could not be reliably documented as the relevant information was not available. Current efforts are underway to establish a regional ART data registry in order to report and monitor availability, effectiveness and safety of ART thus contributing to evidence-based practice and possible development strategies. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for this study. The authors had no competing interests. TRIAL REGISTRATION NUMBER: PROSPERO CRD42016032336

Research involving human subjects must be performed with standards that promote protection of their rights. Several codes were developed and all are unanimous in the following ethic principles: respect for persons, beneficence and justice. The fulfilment of these principles will assure that the dignity, rights, safety and well-being of the participants in a biomedical research are guaranteed.

The need of a special protection to those with diminished autonomy is a common requirement to all codes. Pregnant women are defined as a vulnerable population because of the potential risk of harm of the foetus. Apart from the foetal risk, pregnant women in developing countries have additional potential for vulnerability, as in most of the cases they are economically or/and educationally disadvantaged individuals. Their generally low level of education may put them in a difficult situation to fully understand consent forms and the risk-benefit assessment provided by the researchers.

In recent years, the evidence-based medicine has been an important international goal. Mechanisms to support the use of research-based evidence in developing health policy are being promoted. The research must be sensitive to the potential for vulnerability when designing evidence-based trials and they have to assure that the vulnerable population is being protected.

With the intention to protect the vulnerable population, some groups such as pregnant women have being traditionally excluded from clinical trials. As a result of this exclusion, pregnant women are being exposed to medicines in situations where no evidence-based information is available on efficacy and safety. They are deprived of the benefits of treatment in order to be protected themselves and their offspring from an unknown risk. Although is very clear that protection of a vulnerable population, particularly the pregnant women, is mandatory in the design of any trial, the challenges of the implementation of this principle should be taken into account in order to not increase the gap between the introduction of a pharmaceutical product in the market and the availability of safety information for its use in pregnancy.

In developing countries maternal mortality is an important public health problem. Most maternal deaths occur in the poorest countries particularly in Sub-Saharan Africa. In Mozambique the rate could be between 408-1000 per 100 000 live births according to the source of information. Several studies have addressed different causes of maternal mortality in Africa, eclampsia and malaria being part of the five most reported.

There is strong evidence of the effectiveness of magnesium sulphate (MGSO4) in women with pre-eclampsia and eclampsia but the drug is not available in some countries. The example of MgSO4 has being used to describe failure in translating results of research into policy and/or practice.

For malaria treatment few drugs were considered effective and safe for use during pregnancy including chloroquine, sulphadoxine-pyrimethamine and quinine. The information on safety comes from a long experience of use. The emergency of resistance of P. falciparum to these drugs is limiting its use in most of endemic areas. The artemisinin derivatives are being strongly recommended to be used in combination with other antimalarial drugs. Preclinical studies have consistently shown that artemisinin and its derivatives are embryolethal and teratogenic in animals. Current available information is not adequate to extrapolate the results in animals to humans.

Limited data on the safety profile of antimalarial drugs during pregnancy is a challenge. Nowadays these drugs are used in pregnant women based on retrospective cumulative risk-benefit assessment. Mechanisms of prospectively monitoring the drugs use are required to protect pregnant women from the potential risk.

The aim of this thesis is to describe the (un)availability of drugs and their reasons, as well as, the (un)availability of safety information on drugs needed to be used during pregnancy in Southern Africa, and to propose mechanisms to effectively monitor drug safety in pregnancy in developing countries.

In order to achieve this objective four studies were performed. In the first study a qualitative case-study based on interviews and bibliographic review was performed in Mozambique and Zimbabwe. Factors affecting the (un)availability of MgSO4 were assessed. This study showed that research evidence regarding the effectiveness of MgSO4 for the treatment of eclampsia and pre-eclampsia, was widely known in the study countries. However, the registration, approval, acquisition and distribution of MgSO4, and hence its availability to clinicians, was affected by market and systems failures. With this study we concluded that the low cost of magnesium sulphate, as well as the mechanisms through which it is procured, means that market forces alone cannot be relied upon to ensure its availability. Governments and international organizations must be prepared to intervene to ensure the wide availability of low cost, effective drugs critical to improving public health in Africa.

The second and the third studies shown that antimalarial drugs are being used in pregnant women even without information on its safety profile in this particular group. Robust safety monitoring systems are clearly needed in developing countries to accompany the deployment of new drugs, especially those with a potential teratogenic risk.

The fourth study showed that spontaneous reporting system may be a tool for drug safety monitoring. This system could be used to increase health care providers' and patients' awareness of possible ADRs, and to develop a culture to report these reactions. Spontaneous reporting and pregnancy registries were presented as examples of mechanisms that could and should be in place.

Recommendations on how these systems could be effectively implemented in resource constrained countries were also presented.

All these studies suggest that the definition of vulnerability of pregnant women in developing countries should not be restricted to the potential risk of harm of the foetus (harm-based definition) or to the difficulty of fully understanding consent forms (consent-based definitions). Women are also vulnerable because of the high risk of dying from any cause related to or aggravated by the pregnancy. The implementation of these ethic principles need to take into account the urgent need to implement effective and safe drugs targeted to reduce the burden of maternal morbidity and mortality.
La investigación relativa a los seres humanos debe realizarse dentro de unos estándares que promuevan la protección de sus derechos. Varios códigos han sido desarrollados y todos ellos coinciden unánimemente en los siguientes principios éticos: el respeto por las personas, la beneficencia y la justicia. La realización de estos principios debe asegurar la dignidad, los derechos, la seguridad y el bienestar de los participantes en una investigación biomédica sean preservados.

La necesidad de una protección especial hacia aquellos seres cuya autonomía sea limitada es un requerimiento común para todos los códigos. Las mujeres embarazadas están definidas como un grupo de población vulnerable dado el riesgo potencial de causar daño al feto. Además del riesgo para el feto, las mujeres embarazadas en los países en desarrollo son potencialmente más vulnerables, y suelen contar con desventajas a nivel económico y/o educativo. Su nivel de educación, por lo general bajo, les pone en una situación difícil, dificultando la comprensión de los formularios de consentimiento y la evaluación del riesgo-beneficio que prestan los investigadores.

En los últimos años, la medicina basada en la evidencia ha sido una meta muy importante a nivel internacional. Se están promoviendo mecanismos para respaldar el uso de la evidencia científica para la definición de política de desarrollo de la salud. La investigación debe ser sensible a la vulnerabilidad potencial cuando se diseñan ensayos basados en la evidencia. Además, se debe asegurar que la población vulnerable esté siendo protegida.

Con la intención de proteger a esa población vulnerable, algunos grupos como los de mujeres embarazadas han sido tradicionalmente excluidos de los ensayos clínicos. Como resultado de esta exención, algunas mujeres embarazadas están siendo expuestas a medicamentos de los que no hay información basada en la evidencia en cuanto a su eficacia y seguridad. Este hecho las priva de los beneficios del tratamiento que debería protegerlas, a ellas y sus hijos, de un riesgo desconocido. Aunque está muy claro que proteger a una población vulnerable, particularmente a las mujeres embarazadas, es obligatorio en el diseño de un ensayo clínico, los retos de la implementación de este principio no deberían aumentar el vacío entre la introducción de un producto farmacéutico en el mercado y la disponibilidad de información sobre su seguridad para uso en el embarazo.

En los países en vías de desarrollo la mortalidad materna es un problema importante de salud pública. La mayoría de muertes maternas ocurren en los países más pobres, particularmente en África Subsahariana. En Mozambique el índice puede ser entre 408-1000 por 100000 nacidos vivos, dependiendo de la fuente de información. Diferentes estudios han señalado diversas causas de mortalidad materna en África, encontrándose la eclampsia y la malaria entre las cinco primeras.

Existe una gran evidencia de la eficacia del sulfato de magnesio (MGSO4) en mujeres con pre-eclampsia y eclampsia, sin embargo el fármaco no está disponible en algunos países. El ejemplo del sulfato de magnesio se ha utilizado para describir el fracaso en el traslado de los resultados de la investigación a la práctica y/o política.

Para el tratamiento de la malaria, se consideró seguro el uso durante el embarazo de algunos fármacos incluyendo cloroquina, sulfadoxinapirimetamina y quinina. La información sobre seguridad responde a una gran experiencia de uso. El aumento de resistencia de P. falciparum a estos fármacos está limitando su uso en la mayoría de las zonas endémicas. Actualmente se está recomendando el uso de los derivados de la artemisinina en combinación con otros fármacos antimaláricos. Los estudios preclínicos han mostrado sistemáticamente que la artemisina y sus derivados son embrioletales y teratogénicos en animales. La información disponible hasta la fecha no es adecuada para extrapolar los resultados de los animales a los humanos.

Los datos limitados en el perfil de seguridad de los fármacos antimaláricos durante el embarazo constituyen un desafío. Hoy en día, estos fármacos se usan en mujeres embarazadas basándose en una valoración retrospectiva acumulativa de riesgo-beneficio. Se necesitarían mecanismos de monitorización prospectiva del uso de los fármacos para proteger a las mujeres de su riesgo potencial.

El objetivo de esta tesis es el de describir la disponibilidad o no disponibilidad de los fármacos y sus razones; describir la disponibilidad o no disponibilidad de información sobre la seguridad de estos fármacos que son de uso necesario en el sureste de África. Se pretende también proponer mecanismos efectivos para monitorizar la seguridad de los fármacos en el embarazo en los países en desarrollo.

Para alcanzar estos objetivos se llevaron a cabo cuatro estudios. El primero consistía en un estudio cualitativo de casos basados en entrevistas y en una revisión bibliográfica en Mozambique y Zimbawe. Se evaluaron los factores que afectaban a la disponibilidad o no disponibilidad del sulfato de magnesio. El estudio mostró que la evidencia científica respecto a la eficacia del sulfato de magnesio para el tratamiento de la eclampsia y la pre-eclampsia fue ampliamente conocida en los países del estudio. Sin embargo, el registro, aprobación, adquisición y distribución del sulfato de magnesio y como consecuencia, su disponibilidad para los médicos se vio afectada por fallos de mercado y de sistema. Este estudio concluye que el bajo coste del sulfato de magnesio, así como el mecanismo a través del cual se obtiene, significa que las fuerzas del mercado por si solas no pueden asegurar su disponibilidad. Los gobiernos y las organizaciones internacionales deben estar preparados para intervenir y para asegurar una amplia disponibilidad de fármacos efectivos de bajo coste, críticos para mejorar la salud pública en África.

El segundo y tercer estudio mostraron que los fármacos antimaláricos se están usando en mujeres embarazadas sin contar con información sobre su perfil de seguridad en este grupo particular. Se necesita claramente una monitorización fuerte y segura en los países en vías de desarrollo para acompañar el despliegue de los nuevos fármacos, especialmente aquellos que conllevan un potencial riesgo teratogénico.

El cuarto estudio mostró que el sistema de notificación espontánea puede ser una herramienta para la monitorización de la seguridad de los fármacos. Este sistema se podrá usar para incrementar la consciencia en proveedores de salud y en enfermos sobre las posibles reacciones adversas de fármacos. Ello permitirá desarrollar una cultura de notificación de estas reacciones. La notificación espontánea y los registros de embarazo se presentaron como ejemplos de mecanismos que podrían y deberían ser implementados. Las recomendaciones de cómo estos sistemas podrían ser implementados de forma efectiva en países con recursos limitados también fueron presentadas.

Todos estos estudios sugieren que la definición de vulnerabilidad de las mujeres embarazas en los países en desarrollo no se puede restringir a causa del riesgo potencial de daño al feto, o debido a la dificultad de entender por completo los formularios de consentimiento. También son vulnerables por el riesgo elevado de morir por alguna causa relacionada o agravada por el embarazo. La implementación de estos principios éticos necesita tener en cuenta la necesidad de implementar fármacos diana efectivos y seguros para reducir la mortalidad y morbilidad materna.

A shortage of skilled craft labor in the North American construction industry has been an unfortunate cyclic trend since the late 1980s. This shortage has been reported and discussed frequently by numerous past studies in the context of construction industry. The 2008 U.S. recession was at least one period when the craft shortage temporarily improved, as witnessed by spikes in construction unemployment rates above 20% due to the work slowdowns. However, the current economic recovery period is once again experiencing craft shortages in some sectors of the U.S. construction industry. Although the past literature provides wealth of information about influence of craft labor shortage on construction project, less attention has been given to quantifying the impact of craft labor availability on construction project performance. The primary contribution of this study to the body of knowledge is to fill the gap in existing literature by quantitatively modelling and elucidating the influence of craft labor availability on construction project performance as measured by safety, schedule, productivity and cost. Data from 97 construction projects completed in the U.S. and Canada between 2001 and 2014 were collected from two data sources. A number of t-tests and regression analyses were conducted in both databases to examine the significance of the influence of craft labor shortage on construction project performance. The primary analysis shows that projects that experienced craft shortages underwent significant higher growth in cost overrun, time overrun, safety incident and also lower productivity compared to projects that did not. Further analysis on two databases returned the following models: 1) a Poisson regression model that demonstrates a positive exponential relationship between increased craft worker recruiting difficulty and Occupational Safety and Health Administration (OSHA) Total Number of Recordable Incident Cases per 200,000 Actual Direct Work Hours (TRIR) on construction projects. 2) a statistically significant correlation between increased craft recruiting difficulty and lower project productivity and higher schedule overruns 3) a multiple regression models that demonstrate a relationship between increased construction cost overrun with two variables of increased actual cost and increased craft staffing difficulty. These models are intended to be used by project management team to perceive the risk that skilled craft labor variability poses on project safety, productivity, time, and cost performance. In addition, understanding the level of impact that craft shortages are having through robust statistical analyses is a first step in developing the motivation for industry leaders, communities, and construction stakeholders to address this challenge.

Les systèmes de production et de sûreté de fonctionnement sont d'une importance majeure dans l'industrie des procédés. Leurs performances impactent directement les intérêts de l'industrie. Ces systèmes ont des comportements similaires. Ces comportements peuvent être conceptualisés dans des modèles via des patterns de modélisation. La réutilisation de ces patterns permet de rendre le processus de modélisation à la fois simplifiée et plus efficace.Dans cette thèse, nous proposons un ensemble varié de patterns de modélisation. Ils sont classés en fonction de leur usage, ce qui reflète le fonctionnement d'un pattern de modélisation. Les patterns sont présentés sous forme d’un catalogue. Sur la base de l'étude de nombreux systèmes de production et de sécurité, vingt-quatre (24) patterns de modélisation sont introduits. Chaque pattern est représenté par un ensemble d'éléments structurés. Nous proposons une méthodologie basée sur les patterns pour l'analyse des performances des systèmes de production et de sûreté de fonctionnement.Pour tester la pertinence des patterns de modélisation suggérés, nous avons mené des études expérimentales sur un ensemble de systèmes de production et de sûreté. Tous les systèmes de validation sont extraits de la littérature. Ces systèmes traitent la majorité des difficultés de modélisation détectées auparavant. Une comparaison est effectuée entre les résultats obtenus en utilisant la modélisation basée sur les patterns et ceux rapportés dans la littérature
Production and safety systems are crucial in the process industry. Their performances affect significantly the industry interests. These systems have common behaviors. Such behaviors can be captured in models via modeling patterns. By reusing modeling patterns, the modeling process can be simplified and made more efficient.In this thesis, we propose a versatile set of modeling patterns. They are classified according to their purpose, which reflects what a modeling pattern works for. Modeling patterns are exhibited as a catalog. Based on reviewing numerous production and safety systems, twenty-four (24) modeling patterns are introduced. Each pattern is illustrated with a set of structured items. We propose a pattern-based methodology for performance analysis of production and safety systems.To test the applicability of proposed modeling patterns, we conducted experimental studies on a set of production and safety systems. All systems are extracted from the literature. These systems are declared to cover most of modeling difficulties. Comparisons are performed between the results obtained using modeling patterns and those reported in the literature

Today rise in oil and gas demand, energy crisis, issues concerning energy security and increase in oil prices in the world provoke further exploration and production of oil and gas. The Arctic Sea is the last frontier of abundant hydrocarbon reserves. Having effective regulations, innovative technologies and adequate safety norms, the world has still seen some major accidents such as Gulf of Mexico accident. Knowing that offshore petroleum industry is moving further north in Arctic poses additional challenges due to harsh climatic conditions and remoteness from existing oil and gas infrastructure. The objective of this thesis is to provide an overview of offshore petroleum activity in arctic and sub-arctic areas as well as the accidents which took place in these areas. Furthermore, the accidents are analyzed with respect to the emergency preparedness handling of accidents using the NORSOK Z-013 standard as one basis. The thesis also discusses the anticipated emergency preparedness challenges for arctic and sub-arctic areas. The Arctic Sea is the final destination in the north having enormous amount of hydrocarbons. The harsh weather conditions of the Arctic Sea characterized by polar lows, long nights, extreme fog and sub-zero temperatures have not prevented the countries bordering the Arctic Sea in exploiting the oil and gas resources. Russia, having extended pipeline infrastructure, has the most active part in the Arctic region followed by the US and Norway. The offshore exploration and production activities in the Canadian and Greenland Arctic Sea are gradually progressing. Up to date, there have been very few accidents in the Arctic Sea thereby providing a limited knowledge base for emergency response in the Arctic Sea. The accidents which we have been able to account for are mainly related to blowout, pipeline leak, ship collision and capsize accidents. The accidents have occurred in the Russian Arctic Sea and the Alaskan Arctic Sea.The NORSOK Z-013 standard refers to alert, danger limitation, rescue, evacuation, and normalization as the five emergency preparedness phases and their detailed description is available in the Activities Regulation by the Petroleum Safety Authority in Norway (PSAN). It is stated in the NORSOK Z-013 standard that a set of Defined Situation of Hazard and Accident (DSHA) needs to be defined as part of the risk and emergency preparedness analysis. The set of DSHAs provided in the “Trends in risk level” project is used in this thesis for the classification and analysis of the accidents in the Arctic Sea.The analysis of the accidents in the Arctic Sea shows that all the emergency operations went through the phases of alert and normalization while the oil spill related accidents did not pass through escape and evacuate operations as there were no personnel involved in these accidents. All the emergency operations were affected by bad and tough weather conditions. Advanced emergency preparedness tools, equipment and technology are needed for effective emergency operations under such conditions. Due to scarcity of accidents in the Arctic Sea, only four DSHAs (out of 12) have been experienced, or at least reported. It may be that some of the remaining DSHAs are not reported due to minor consequences. In addition to the lessons learned from the emergency response operations for the accidents experienced in the Arctic Sea, there are also some emergency preparedness challenges which can be anticipated. The challenging weather conditions due to sudden polar lows, strong winds, spray icing, snowstorms and severe fog can hamper the emergency operations. Furthermore, long distances and lack of infrastructure can create communication and logistic problems and can result in delay of rescue and evacuation operations. Robust and reliable ice and weather data is a challenge due to global warming and may become a limiting factor for the adequate design of offshore equipment. The use and maintenance of emergency response equipment is also a challenge in sometimes dark, snowy and foggy areas of the Arctic Sea and the Barents Sea.

The industrialised world of today is characterised by transformation and concepts such as downsising, rightsising and restructuring have become a reality. South Africa is not excluded from this worldwide phenomenon. Economic and political changes as well as the shrinking labour market are also aggravating circumstances, which lead to increased job insecurity. This phenomenon might have a negative impact on employees' work engagement Due to all these changes, most organisations have to survive in a competitive global economy. Their survival depends on their ability to satisfy customer needs, while achieving quality, flexibility, innovation and organisational responsibility by the engagement and commitment of employees. The objective of this study was to investigate the relationships between antecedents (work role fit, co-worker relations, supervisor relations, co-worker norms, self-consciousness, resources and growth), psychological conditions (i.e. psychological meaningfuhaess, psychological availability, and psychological safety) and work engagement in a financial institution. A cross-sectional survey design was utilised. Employees (N= 132) in a financial institution, more specifically the branch-banking unit of FirstRand Group in the Free State Province, were included in the study. The Work Experience Scale and the Work Engagement Scale were administered together with a biographical questionnaire. Descriptive and inferential statistics were used to analyse the data. The results showed that psychological meaningfuhaess and psychological availability were significant predictors of work engagement. Cognitive, emotional and physical resources had the strongest effect on work engagement. Multiple regression analyses showed that psychological meaningfuhaess partially mediated the relationship between work role fit, co-worker relations, growth and work engagement. A total of 5% of the variance in psychological meaningfulness and a total of 2% of the variance in psychological availability were predicted by work role fit. Psychological availability partially mediated the relationship between resources, self-consciousness and work engagement. Recommendations for future research were made.
Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2009.

Pesticide firms in the United States must undertake costly, crop-specific Environmental Protection Agency (EPA) safety tests to register their pesticides for sale to farmers of commercial crops. Firms also must pay annual registration fees and periodically undertake additional safety tests on each pesticide?s crop-specific registrations. These requirements create a market unlike others because firms may not freely enter or remain in a crop?s pesticide market. The EPA can raise and lower registration requirements to discourage or encourage registration of pesticides with certain safety characteristics on crops with particular production or consumption patterns.

Used effectively, these powers can enable the EPA to promote safety by encouraging registration of the safest pesticides in the widest number of markets, while limiting availability of unsafe pesticides. Used poorly, these powers can restrict even safe pesticides from reaching markets, especially minor ones.

This dissertation evaluates the success of the pesticide regulatory system. A model that includes the EPA?s standard-setting process and a representative pesticide firm?s registration decision-making is used to demonstrate how registrations come about. The model shows how EPA and firm behavior cause registrations to depend on the characteristics of pesticides and crops.

The study required compilation of an extensive dataset of crop and pesticide characteristics and registration data through the 1990s. The data are used in logit analysis to evaluate the relative importance of crop and chemical characteristics in determining registrations.

The results show some evidence that the system successfully encourages registration of safer pesticides. Pesticides that are less likely to cause chronic health damage are more likely to be registered. Pesticides that are safer for the eyes of farm workers are more likely to be registered.

The results also show undesirable relationships. Crops with lower national value are less likely to have registrations. After controlling for crop value, herbicides are less likely to be registered for fruits and vegetables and for crops with high per-acre value. Pesticides that are more dangerous if eaten are more likely to gain registrations. There is only limited evidence that EPA initiatives have caused safety to become a more important determinant of pesticide registrations during the 1990s.

The present study tested a nomological net of work engagement that was derived from its extant research. Two of the main work engagement models that have been presented and empirically tested in the literature, the JD-R model and Kahn’s model, were integrated to test the effects that job features and personal characteristics can have on work engagement through the psychological conditions of meaningfulness, safety, and availability. In this study, safety refers to psychological perceptions of safety and not workplace safety behaviors. The job features that were tested in this model included person-job fit, autonomy, co-worker relations, supervisor support, procedural justice, and interactional justice, while the personal characteristics consisted of self-consciousness, self-efficacy, extraversion, and neuroticism. Thirty-four hypotheses and a conceptual model were tested in order to establish the viability of this nomological net of work engagement in which it was expected that meaningfulness would mediate the relationships between job features and work engagement, safety would mediate the relationships that job features and personal characteristics have with work engagement, and availability (physical, emotional, and cognitive resources) would mediate the relationships that personal characteristics have with work engagement. Furthermore, analyses were run in order to determine the factor structure of work engagement, assess whether or not it exhibits differential validity from organizational commitment and job satisfaction, and confirm that it is positively related to the outcome variable of organizational citizenship behavior (OCB). The final sample consisted of 500 workers from an online labor market who responded to a questionnaire composed of measures of all constructs included in this study. Findings show that work engagement is best represented as a three-factor construct, composed of vigor, dedication and absorption. Furthermore, support was found for the distinction of work engagement from the related constructs of organizational commitment and job satisfaction. With regard to the proposed model, meaningfulness proved to be the strongest predictor of work engagement. Results show that it partially mediates the relationships that all job features have with work engagement. Safety proved to be a partial mediator of the relationships that autonomy, co-worker relations, supervisor support, procedural justice, interactional justice, and self-efficacy have with work engagement, and fully mediate the relationship between neuroticism and work engagement. Findings also show that availability partially mediates the positive relationships that extraversion and self-efficacy have with work engagement, and fully mediates the negative relationship that neuroticism has with work engagement. Finally, a positive relationship was found between work engagement and OCB. Research and organizational implications are discussed.

This report elaborates on the master degree thesis developed by the candidate within the company Superjet International. The performed activity focuses on the study and design of VAMP (Virtual Aircraft Multipurpose Platform). VAMP is a new interactive platform, not necessarily limited to the Aeronautical sector, aimed to analyse technical failures, identify risk and recommend the most appropriate corrective actions for maintenance cost reduction, taking into account reliability, availability, maintainability and safety.

The objective of this thesis is to identify, which hazards and failures in operation process will affect Reliability, Availability, Maintainability and Safety of floating offshore structures. The focus is on Dynamic Positioning (DP) system that has the responsibility of keeping the offshore structure in the upright position operation. DP system is one of the most critical subsystems on these types of structures in terms of safety of operation and failure risk costs. Reliability of the system in this thesis has been analyzed in qualitative and quantitativeb methods. In qualitative method to find the effective parameters on the reliability of the DPb system, Reliability Centered Maintenance (RCM ) and its application as a main tool have been used. To achieve the aim it has been tried to define the events and accidents which could be generated by the identified hazards then tried to determine the consequences of the realized accidents. In this step three categories are taken in to account including, safety, operation, and equipment. Next phase should be concentrated on considering and analyzing the relevant processes and the root causes which result in the identified hazard. After clarifying all probable root causes it has been tried to prioritize the root causes and specifying the necessary preventive actions. The aim of this step is either decreasing the occurrence of root causes or increasing the detectability of hazards. In the last part quantitative method has been used to measure the amounts of Reliability, Availability and Maintainability of the system, based on MTBF and MTTR of different components of the system and it has been tried to present the solutions to improve system reliability based on components RCM tables. Further, assuming DP system as human- machine system safety assessment has been included to indicate human factors in the reliability of the system beside probable failure of the components of the system.

Organisations across the world are faced with the same challenges of how to get employees to be totally immersed in their role at work. People occupy roles at work. There is no sense in engaging employees if management is not going to invest in the effort of placing these employees in appropriate roles and supporting them to be engaged in their work. There are generalised states that employees occupy: people are to some degree job involved, committed to organisations, or alienated at work in the form of self-estrangement. These concepts suggest that employees can use varying degrees of themselves, physically, cognitively and emotionally, in the roles they perform. The primary objective of this research was to explore the three psychological processes, meaningfulness, safety and availability to be determinants of work engagement. Another objective was also to explore the influence of the antecedent conditions, namely work role fit, co-worker relations, supervisor relations, co-worker norms, self-consciousness and resources on work engagement. The study also investigated whether the psychological processes mediate the relationships between antecedent conditions and work engagement. A survey design was used to reach the research objectives. The specific design used was the cross-sectional design. Employees across all levels (N=165)i n a chemical industry in the Vaal Triangle were targeted for this research. Four standardised questionnaires were used in the empirical study, namely the Psychological Processes Questionnaire, Antecedent Conditions Questionnaire, Work Engagement Questionnaire as well as a Biographical Questionnaire. Multiple regression analyses showed that psychological meaningfulness mediated the relationship between work role fit and work engagement. A total of 32% of the variance in psychological meaningfulness was predicted by work role fit. Psychological meaningfulness predicted 29% of the variance in work engagement. Psychological availability mediated the relationship between available resources and work engagement. The analysis indicated that 11% of the variance in engagement was predicted by resources. Psychological availability predicted 3 1 % of the variance in engagement. Recommendations for future research were made.
Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2007.

A geração de produtos de sucesso está associada ao cumprimento dos anseios e desejos dos consumidores. Diversos fatores caracterizam esses anseios, sendo que um grupo de fatores possui especial característica, esse grupo abrange a confiabilidade, a mantenabilidade e a segurança. A gestão desses três fatores implica num olhar profundo em todo ciclo de vida do produto e não somente no projeto, na manufatura, ou na fase de testes funcionais. O projeto que segue busca discutir a implementação de um sistema de gestão para confiabilidade, mantenabilidade e segurança em empresas que desenvolvem produtos com fins lucrativos, mantendo profunda atenção as diretrizes da engenharia simultânea. Serão abordados aspectos dessa implementação, primeiramente definindo o que deve ser gerido, as razões pelas quais se deve buscar essa gestão, em qual estrutura organizacional o mecanismo de gestão deve ser aplicado, quais ferramentas de gestão são pertinentes e como essas ferramentas podem ser implementadas, ressaltando que cuidados merecem atenção e que resultados são esperados. Por fim será apresentado um caso de implementação de uma das ferramentas mais importantes para o sistema de gestão, o sistema FRACAS, \"Failure Reporting, Analysis and Corrective Action System\", que organiza e padroniza a coleta de dados, possibilita análises e fundamenta a tomada de ações de melhoria. Para o desenvolvimento de toda a discussão serão abordados temas diversos como o ciclo de vida dos produtos, projetos, programas, qualidade, sistemas de informação, tecnologias de banco de dados e obviamente confiabilidade, mantenabilidade e segurança. O estudo de caso partirá de um produto já existente que possua dados de campo, seguindo para a construção de um sistema de informação capaz de coletar, organizar, filtrar e pré-analisar as informações. O principal objetivo do trabalho é gerar diretrizes para empresas que desenvolvem produtos que exijam grande esforço de engenharia na otimização de seu processo de decisão, mostrando algumas opções para controlar suas operações, seus programas e projetos no âmbito da confiabilidade, mantenabilidade, disponibilidade e segurança.
The creation of successful products is linked with the ability to reach longings and desires of costumers. Several factors compose these desires and a group of factors have a special characteristic, this group embraces reliability, maintainability and safety. The management of these three factors carries in a deep look of the entire product\'s life cycle and not only in design, manufacture or in functional test phase. The following work intend discuss an implementation of a management system for reliability, maintainability and safety in companies that develop products seeking profit and keeping intense attention to rules from concurrent engineering. Will be discussed aspects of this implementation, firstly defining what should be managed, the reasons to manage, what kind of organizational structure should control this management system, what management tools are relevant and how these tools can be implemented, what special attention any aspect needs and what results are expected. Finally will be presented an implementation case of one of most important tool for the management system, the system FRACAS, \"Failure Reporting, Analysis and Corrective Action System\", that organizes and standardizes the data collection, making some analysis possible and creating basis for the decision making process. During the development of all this discussion a broad number of subjects will be pointed, like product\'s life cycle, designs, projects, quality, information systems, data base technology e obviously reliability, maintainability and safety. The case will start from a preexistent product that already have available field data, following to construction of an information system capable to collect, organize, filter and pre-analyze the information. The main goal of this work is to orientate companies that develop products that demand huge engineering efforts in optimization of making decisions process, showing some options to control their operations, their programs and projects, concerning reliability, maintainability, availability and safety.

In questo elaborato si esporranno le attività svolte per implementare all’interno di un magazzino automatico il concetto di manutenzione autonoma. Nel primo capitolo verranno trattati i principi manutentivi in generale, partendo dalla manutenzione tradizionale e dalle varie politiche manutentive per poi passare al concetto di manutenzione all’interno della Lean Production, trattando anche velocemente quelli che sono i pilastri su cui si basa in modo da entrare più nello specifico all’interno del concetto di manutenzione autonoma. Inoltre verranno trattate anche quelle che sono le normative vigenti per la gestione della manutenzione nel contesto aziendale. Nel capitolo successivo si parlerà in modo superficiale dall’azienda in cui si è svolto il progetto, trattando poi i sistemi automatici presenti in area logistica, così da potersi soffermare nello specifico sul magazzino automatico o High bay Warehouse. Il terzo capitolo tratterà invece nello specifico delle attività che si sono svolte per conseguire gli obiettivi prefissati. In particolare si analizzeranno i primi due step per l’implementazione della manutenzione autonoma. Il primo si incentra principalmente sulla sicurezza e la conoscenza dell’impianto. Verranno quindi trattate velocemente anche tematiche relative alla sicurezza sul lavoro che sono state considerate in fase di progetto e redatto documenti come la Safey Map e la LOTO Map. Il secondo step invece si incentra più sul mantenimento dello stesso in una condizione di ordine e pulizia funzionale. Ogni step del processo è supportato attraverso degli strumenti consolidati e standardizzati all’interno del mondo Philip Morris come CIL e CL, i quali verranno analizzati nello specifico nei rispettivi capitoli. Nel capitolo quarto vengono poi fatte considerazioni economiche con i risultati ottenuti dallo sviluppo del progetto attraverso i dati considerati nella Baseline che sono poi stati ricalcolati.

O transporte aéreo e a indústria de sistemas de defesa foram setores pioneiros na utilização de sistemas computacionais críticos, incrementando os níveis de automação nas atividades de controle do espaço aéreo. Com o crescimento desses setores, verificado pela expansão dos números de vôos, volumes de cargas e usuários, assim como pela ampliação e diversidade das operações militares, os sistemas de controle têm assumido maior complexidade técnica, introduzindo novos recursos de automação ou facilidades adicionais de apoio para funções exercidas manualmente. Essa situação tem ampliado a dependência dos serviços prestados, relativamente à disponibilidade dos sistemas computacionais. Diretrizes de projeto e procedimentos operacionais são estabelecidos para manter os níveis de segurança nos casos de falha, no entanto a disponibilidade torna-se parâmetro crítico, na medida em que algumas falhas podem afetar a eficiência nominal da prestação dos serviços. Nesse cenário, este trabalho propõe um modelo para avaliação da disponibilidade de sistemas de controle do espaço aéreo, a partir de recursos de análises da teoria de filas. Inicialmente é citado um modelo geral para análise de disponibilidade de data centers. Em seguida, é apresentada uma extensão do modelo geral para análise da disponibilidade em sistemas de controle do espaço aéreo. Para isso, considerou-se a intervenção humana existente nessa atividade, cujas decisões de controle são exercidas por operadores qualificados (controladores), tanto nas atividades inerentes ao serviço de controle, quanto nos casos de degradação, nos quais os operadores ou técnicos de manutenção assumem alguma tarefa de reparo, decorrente da eventual indisponibilidade de funções do sistema.
Due to the growth in airspace utilization, which can be verified both in terms of the expansions in aerial movements, airports and volumes of transported passengers and cargo, as well as in terms of the expansion of military operations demands and diversity, airspace control activities have been increasing their technical complexity, introducing new features into the existent automation systems or creating additional resources for the automation of some functions previously performed by human operators. This situation has increased the dependence on the availability of the computer systems involved in the services provided by control centers. Project directives and operational procedures are established in order to maintain the safety integrity levels of the systems, in case any failure occurs. However, the availability becomes a critical parameter, once failure events can force an undesirable state of degraded operation, jeopardizing the nominal capacity of the services being performed through any controlled airspace. In this scenario, this work presents an availability model for the computer systems used in airspace control centers, based on analysis from queuing theory. A general model is first presented, referencing a case study that describes the use of queuing models to access the availability of generic data centers. Further considerations are introduced to extend this general model in order to propose its application for the specific computer systems used in airspace control centers, where operational control relies on human activities. In this case, system operation involves intensive use of human-machine interfaces (HMI), for the regular control services provided, and additional technical or operational maintenance activities, occasionally imposed to repair a momentary loss of any function of the system.

Em indústria de alimentos são aplicados máquinas e equipamentos para processamento de alimentos, os quais exigem lubrificação para garantir seu pleno estado de funcionamento. Porém o mesmo lubrificante que auxilia o funcionamento do maquinário é considerado um risco potencial de contaminação do produto em suas etapas de processamento, vindo a interferir em sua qualidade. Além deste fator, uma inadequada gestão do processo de lubrificação de máquinas e equipamentos podem gerar eventos de falhas, impactando na disponibilidade e confiabilidade operacional do sistema industrial como todo. O objeto da pesquisa desenvolvida nesta tese de doutorado é o desenvolvimento de um método de seleção de política de lubrificação industrial centrada em confiabilidade voltada especificamente para maquinário empregado na fabricação de alimentos, e visa analisar os eventos de falhas ocorridos no maquinário, os quais relacionados com o processo de lubrificação industrial, bem como, a relação das atividades de lubrificação na geração de foco de potencial risco que propicie perda de qualidade e inocuidade do produto. O método é estruturado na identificação das variáveis envolvidas no processo de lubrificação industrial e análise de seus impactos sobre a geração de eventos de falhas e potencial foco de risco de perda de qualidade e inocuidade do produto, Esta análise visa direcionar a tomada de decisão quanto a estrutura da política de lubrificação industrial adequada a cada ativo industrial instalado na indústria de alimentos. A validação do método de seleção de política de lubrificação centrada em confiabilidade deu-se através da aplicação de sua metodologia em um sistema reparável, uma máquina cobrideira, instalada em uma indústria de alimentos, localizada na região metropolitana de Curitiba. A análise estatística do comportamento da tendência de falhas neste ativo industrial conjuntamente com a análise funcional dos modos de falhas relacionados com o processo de lubrificação industrial, possibilitou estruturar uma política de lubrificação industrial adequada para máquina cobrideira. Esta política de lubrificação contempla ações que resultaram no aumento de produtividade anual da máquina cobrideira em 0,16%, isto significa 280.830 unidades (equivalente a 7,02 toneladas) produzidas a mais no ano de 2014 em relação a 2013, e na melhoria dos indicadores de desempenho de manutenção e disponibilidade operacional da máquina cobrideira. Além disto, a aplicação do método desenvolvido estruturou procedimentos de modo de execução e monitoramento das atividades de lubrificação, os quais visam garantir a qualidade do produto durante as etapas de fabricação conjuntamente com a melhoria de desempenho e produtividade do sistema industrial.
In the food industry, machinery and equipment for food processing are used. They require lubrication to ensure they\'re working properly. However, the same lubricant which assists the operation of the machinery is considered a potential contamination to the product in its processing steps, impacting on their quality. The improper management of the lubrication process of machinery and equipment may lead to fault events, impacting on the availability and operational reliability of the industrial system as a whole. The research object developed in this doctorate thesis shows the development of a selection method of an industrial lubrication policy focused on reliability. Such policy is designed specifically for machinery used in the manufacture of foods. It analyzes the failure events in the machinery due to the lubrication process and. It also analyzes the connection between the lubricating activities and the potential risk of loss product quality and safety. The method is structured to identify the variables involved in the industrial lubrication process and analyzes their impact they have on fault events and potential source of risk of product quality loss. This analysis aims to guide decision-making regarding the structure of the adequate industrial lubrication policy to each industrial asset installed in the food industry. The validation of the lubrication policy selection method focused on reliability occurred through the application of its methodology in a repairable system, a coating machine, installed in a food industry located in the metropolitan region of Curitiba. The statistical analysis of the fault trend behavior in this industrial asset together with the functional analysis of failure modes related to the industrial lubrication process made it possible to structure a suitable policy for the industrial lubrication of the coating machine. This lubrication policy includes actions that resulted in the increase of the annual productivity of the coating machine by 0.16%. It means 280,830 more units (equivalent to 7.02 tons) were produced in 2014 than in 2013. It also improved the maintenance performance indicators and the operational availability of the coating machine. Furthermore, the application of the method structured procedures of execution mode and monitoring of lubrication activities. The aim was to ensure the quality of the product during the manufacturing steps together with the improvement of the performance and productivity of the industrial system.

La conception d'applications distribuées implique fondamentalement un compromis entre la sûreté et les performances. Nous nous concentrons sur les cas où la sûreté est la principale exigence. Dans le cadre des systèmes distribués basés sur l'état, nous proposons une méthodologie de preuve pour établir qu'une application donnée maintient un invariant donné. Notre approche permet de raisonner sur les opérations individuelles séparément. Nous démontrons que nos règles sont correctes et, à l'aide d'un moteur de preuve, nous illustrons leur utilisation par quelques exemples représentatifs. Pour les opérations conflictuelles, le développeur peut choisir entre la résolution de conflit ou la coordination. Nous présentons une nouvelle structure de données en forme d'arbre répliqué qui prend en charge les déplacements atomiques concurrents sans coordination et qui maintient l'invariant de l'arbre. Notre analyse identifie les cas où les déplacements concurrents sont intrinsèquement sûrs. Pour les autres cas, nous concevons un algorithme de résolution des conflits. La contrepartie est que dans certains cas, une opération de déplacement est "perdante". Étant donné la coordination requise par certaines applications pour la sûreté, elle peut être implémentée de nombreuses façons différentes. Même en se limitant aux verrous, ceux-ci peuvent utiliser diverses configurations qui diffèrent par: la granularité, le type et le placement. La performance de chaque configuration dépend de la charge de travail. Nous étudions le "treillis de coordination", l'espace de conception des configurations de verrouillage, et définissons un ensemble de mesures pour y naviguer systématiquement
Designing distributed applications involves a fundamental trade-off between safety and performance as described by CAP theorem. We focus on the cases where safety is the top requirement.For the subclass of state-based distributed systems, we propose a proof methodology for establishing that a given application maintains a given invariant. Our approach allows reasoning about individual operations separately. We demonstrate that our rules are sound, and with a mechanized proof engine, we illustrate their use with some representative examples. For conflicting operations, the developer can choose between conflict resolution or coordination. We present a novel replicated tree data structure that supports coordination-free concurrent atomic moves, and arguably maintains the tree invariant. Our analysis identifies cases where concurrent moves are inherently safe. For the remaining cases we devise a conflict resolution algorithm. The trade-off is that in some cases a move operation "loses". Given the coordination required by some application for safety, it can be implemented in many different ways. Even restricting to locks, they can use various configurations, differing by lock granularity, type, and placement. The performance of each configuration depends on workload. We study the "coordination lattice", i.e., design space of lock configurations, and define a set of metrics to systematically navigate them

L’acquisition de paramètres physiques tels que la température, la pression, le couple et la vitesse est nécessaire aux systèmes aéronautiques critiques afin d’atteindre et d’assurer les performances requises de disponibilité et de sécurité de fonctionnement. L’acquisition de ces paramètres physiques nécessite donc la mise en oeuvre de technologies et de techniques hautement éprouvées pouvant supporter les conditions de fonctionnement sévères.L'objectif des travaux présentés dans ce mémoire est de proposer une nouvelle architecture de chaîne d'acquisition de grandeurs physiques pour être intégrée à un système aéronautique critique. Le but de cette architecture est d'améliorer l'intégrité des données mesurées tout en maintenant leur disponibilité et le niveau de sûreté de fonctionnement propre aux systèmes aéronautiques de haute criticité. La solution se déploie sous la forme d'une amélioration de la tolérance aux défauts de la chaîne de traitement du signal issu du capteur. Pour ce faire, nous intégrons des fonctions supplémentaires, dont le modèle mathématique de la chaîne d'acquisition, rendant ainsi le système plus intelligent.Dans le cadre de nos travaux de recherche, nous nous appuyons sur les spécifications techniques d'un projet industriel typique des systèmes aéronautiques critiques, qui est le coeur de notre thématique principale
The acquisition of physical parameters as such as temperature, pressure, torque, and speed are necessary to flight critical systems in order to reach and ensure safety and availability required. Consequently, it requires implementing high technologies and techniques which are able to work in rugged environments.The aim of our work is to design a new architecture for sensor acquisition systems in order to be integrated onto a flight critical system. The goal of the architecture is to ensure data integrity, system's availability and safety relative to airborne critical systems. The solution adds the fault tolerance ability to the signal conditioning. Consequently, we implement additional functionalities, as such as mathematical model of the signal conditioning, in order to make the acquisition system more intelligent.Our research work is partially based on technical specifications from SYRENA project, which is a typical example of flight critical systems, which is the main thematic of our purpose

One in every 4 people living with the Human Immunodeficiency Virus (HIV) are women. The leading cause of infection is heterosexual contact. The purpose of this quantitative, correlational study was to examine the relationship between gender ratio perception and masculine ideology and a woman's decision to use condoms during her sexual activity. The theory of gender and power and the theory of planned behavior served as the theoretical frameworks for this study. The perceptions of gender ratios, as measured by the Gender Ratio Imbalance Beliefs and Behaviors Scale (GRIBBS) subscale, GRIBeliefs, and masculine ideologies, as measured by the Gender Role Beliefs Scale (GRBS), served as independent variables, while condom use behaviors, as measured by the Gender Ratio Imbalance Beliefs and Behaviors Scale (GRIBBS) subscale, GRIBehaviors, served as the dependent variable. Covariates included demographic factors, as well as behavioral factors. A purposeful, convenience sample (n=55) via the Walden University research pool was utilized, enabling researchers to use readily available data that represented college educated women. Descriptive statistics, independent t-tests, correlational analysis, as well as multiple linear regression were used to examine the aforementioned perceptions of study participants. Correlation analyses and multiple regression indicated no statistically significant correlations between gender ratio imbalance, masculine ideology, and condom use, while controlling for race, employment status, religion, religious devoutness, sexual orientation, relationship status, STD history (self), and partner STD history. Social change is indicated via the results illustrating the possible empowerment of women regarding their sexual health.

Les travaux présentés dans ce manuscrit visent à développer des modèles de coût/performances pour améliorer les décisions de maintenance sur les infrastructures ferroviaires exploitées dans un environnement de plus en plus contraint: trafic accru, détérioration accélérée, temps de maintenance réduits. Les modèles de maintenance proposés sont construits à base de réseaux de Petri colorés ; ils sont animés par simulation de Monte Carlo pour estimer les performances (en termes de coût et de disponibilité) des politiques de maintenance considérées. Ils sont développés aux niveaux "composant" et "réseau", et plusieurs problèmes de maintenance différents sont étudiés. Au niveau "composant" (rail), des politiques de maintenance mettant en jeu différents niveaux d'information de surveillance sont comparées pour montrer l'intérêt de surveiller la détérioration graduelle du composant. L'effet de l'existence d'un délai de maintenance est également étudié pour les politiques conditionnelle et périodique. Au niveau système (ligne), une maintenance mettant en jeu différents types d'inspections complémentaires (automatique ou visuelle) est d'abord étudiée. On s'intéresse ensuite au cas de figure où l'évolution de la détérioration dépend du mode d'utilisation et de la charge de la voie : le problème de maintenance étudié vise alors à définir un réglage optimal des paramètres d'exploitation de la voie (vitesse limite) et de maintenance (délai d'intervention)
The aim of this thesis research work is to propose maintenance models for railways infrastructures that can help to make better maintenance decisions in the more constrained environment that the railway industry has to face, e.g. increased traffic loads, faster deterioration, longer maintenance planning procedures, shorter maintenance times. The proposed maintenance models are built using Coloured Petri nets; they are animated through Monte Carlo simulations to estimate the performance of the considered maintenance policies in terms of cost and availability. The maintenance models are developed both at the component and network levels, and several different maintenance problems are considered. At the rail component level, maintenance policies with different level of monitoring information (level of gradual deterioration vs binary working state) are compared to show the benefits of gathering monitoring information on the deterioration level. The effect of preventive maintenance delays is also investigated for both condition-based inspection policies and periodic inspection policies on a gradually deteriorating component. At the line level, a maintenance policy based on a two-level inspection procedure is first investigated. Then, considering the case when the deterioration process depends on the operation modes (normal vs limited speed), a maintenance optimization problem is solved to determine an optimal tuning of the repair delay and speed restriction

Le sol est la couche supérieure de l’écorce terrestre, la surface plane qui s’étire d’un horizon à un autre. Il est la terre que l’on laboure, le sable que l’on égraine, base que l’on piétine, point d’attache des hommes à un territoire : jardin, région ou Etat. Les sols, ces écosystèmes fragiles aux multiples fonctions, à l’origine de tout autant de services écologiques, sont les garants de la qualité de l’environnement. Le droit a intégré diverses conceptions de la notion de la qualité des sols. Mais loin de constituer un statut de protection, cette intégration éparse est indifférente, a priori, leurs qualités environnementales. Or, les sols sont une ressource finie et leur utilisation irraisonnée conduit à leur dégradation, souvent irréversible, et à leur raréfaction. Progressivement, le droit s’est enrichi d’éléments relatifs à la multifonctionnalité des sols, intégrant des pratiques garantissant leur utilisation durable ou organisant de façon cohérente leur affectation. Cette approche utilitariste de la qualité des sols s’avère sélective et demeure concentrée sur la préservation des services écologiques directement bénéfiques à l’homme, dont celui de production des matières premières alimentaires, au détriment des services indirects ou déterritorialisés, tel que celui de stockage de carbone. Cette approche est toutefois complétée par l’émergence d’une conception objectiviste de la qualité, qui révèle les propensions du droit à protéger la valeur intrinsèque des sols
The soil is the upper layer of the earth’s crust, the plan surface that stretches from one horizon to the other. It is the crop lands, the scattering sand, the ground we trample on, the link between men and their territory: garden, region, state. The soils, those fragile and multifunctional ecosystems, provide many ecological services and guarantee the environmental quality. The law contains several conceptions of the notion of soils quality. But, far from constituting a protection status, this integration ignores, a priori, their environmental qualities. However, the soils are a finite resource and their non-sustainable use leads to their degradation, often irreversible, and to their growing scarcity. Progressively, the law added elements of soils multifonctionality, integrating sustainable practices. This utilitarian approach of soil quality proves to be selective and remains focused on the preservation of a small part of all the ecological services: the ones that men directly need, like food production and ignores the indirect ones like carbon storage. Nevertheless, this approach is complemented by the raising of an objectivist conception of quality, which reveals the propensity of the law to take into account the intrinsic value of soils

Ces travaux s'intéressent à l'estimation de la fiabilité des évacuateurs de crues vannés. Le comportement fiabiliste de ces systèmes hydrauliques dépend à la fois d'événements aléatoires discrets, mais aussi de l'évolution d'une variable déterministe continue : ce sont des systèmes dynamiques hybrides. Pour ces systèmes, l'événement redouté est réalisé lorsque le niveau de la retenue atteint un seuil de sûreté. La démarche de fiabilité dynamique proposée dans cette thèse vise à prendre en compte l'information temporelle, de la modélisation à la synthèse d'indicateurs fiabilistes pour l'aide à la décision et développe deux contributions : 1) L'élaboration d'une base de connaissances dédiée à la description des évacuateurs de crues en termes de fiabilité dynamique. Chaque classe de composants est décrite par un automate stochastique hybride dont les états sont les différentes phases de son fonctionnement. 2) Le suivi de la simulation de Monte Carlo, le traitement et l'analyse des "histoires" (séquence de tous les états activés et des dates d'activation) obtenues en simulation. Cela permet de construire des indicateurs de fiabilité classique (probabilité d'occurrence de l'évènement redouté, identification des coupes équivalentes prépondérantes, ...). Des indicateurs de fiabilité dynamique basés sur la classification des histoires en fonction des dates de défaillance des composants concernés et sur l'estimation de l'importance dynamique sont aussi proposés.

Die Landwirtschaft ist heute der wichtigste Treiber der globalen Degradation von Ökosystemen. Es existiert jedoch wenig konkretes Wissen, wie Ökosysteme zu schützen sind und gleichzeitig die Nahrungsproduktion für die wachsende Weltbevölkerung gesichert werden kann. In dieser Dissertation untersuche ich Optimierungsmöglichkeiten im landwirtschaftlichen Wassermanagement. Ich quantifiziere praxisorientierte Verbesserungen der Regenwassernutzung und Optimierungen von Bewässerungssystemen, unter Einhaltung der „environmental flow requirements“ (EFRs). Um diese komplexen Interaktionen zu untersuchen, entwickle ich ein agro-hydrologisches Modell auf Basis detaillierter, mechanistischer Prozessabbildung weiter. Erstens, 39% der derzeitigen Wasserentnahmen für Bewässerung sind nicht nachhaltig und somit auf Kosten der Ökosysteme. Zweitens, solche lokalen Wasserentnahmegrenzen legen nahe, dass die globale Grenze für den menschlichen Wasserverbrauch deutlich niedriger liegt, als bisher angenommen (2800 vs 4000 km3yr-1). Drittens, die Implementierung von EFRs würde die landwirtschaftliche Produktion erheblich beeinträchtigen, mit >20% in stark bewässerten Gebieten. Verbesserte Nutzung des Niederschlagswassers und die Optimierung von Bewässerungssystemen, können die weltweite Nahrungsmittelproduktion allerdings um rund 40% nachhaltig steigern - ausreichend, um die Nahrungsmittellücke der wachsenden Weltbevölkerung bis 2050 zu halbieren. Zusammenfassend stellt diese Arbeit die erste umfassende und systematische Einschätzung globaler Potentiale der nachhaltigen Intensivierung der Landwirtschaft aus der Wasserperspektive dar. Die in dieser Arbeit vorgebrachten innovativen und quantitativen Erkenntnisse legen nahe, dass das Potential der diskutierten Interventionen höhere politische Aufmerksamkeit erfahren sollte. Meine Ergebnisse können eine konkretere Diskussion zur Umsetzung der Sustainable Development Goals untermauern.
Agriculture is today''s most important driver of ecosystem degradation across scales. However, there is little evidence on how to attain the historic twin-challenge of maintaining environmental integrity while producing enough food for a growing world population. In this thesis, I assess opportunities in agricultural water management to reconcile future food needs with environmental limits to water use. I explore solution-oriented ways to improve rainfed and irrigation systems alike, while safeguarding environmental flows (EFRs). To study complex interactions quantitatively, I advanced a state-of-the-art global modeling framework based on detailed, mechanistic process representation. First, a systematic upscaling of EFRs to global coverage indicates that 39% of current freshwater withdrawals for irrigation are unsustainable and occur at the cost of ecosystems. Second, accounting for EFRs indicates that the planetary boundary for freshwater use might be notably lower (2800 vs. 4000 km3yr-1) than expected. Third, maintaining EFRs would significantly affect food production, cutting >20% of total kcal production across intensely irrigated areas. Fourth, improving irrigation systems in combination with optimizing the use of precipitation water, provides effective and accessible measures to compensate for adverse impacts from protecting EFRs and climate change. Such integrated interventions could sustainably intensify global food production (+40% kcal) to the degree sufficient to halve the global food gap by 2050. In conclusion, this thesis provides the first comprehensive and systematic assessment of hitherto largely unquantified water opportunities in sustainable intensification of agriculture. While requiring corroboration by finer-scale research, the innovative quantitative foundation provided in this thesis suggests that farm water management merits a rise in political attention, and it can inform a more comprehensive discussion of related SDG target interactions.

Reliability-Cenetred Maintenance (RCM) is a well-known maintenance process developed in the aviation industry. It has yielded great success and hence was the process adapted to be used in the more industrial environments, such as the process developed by Moubray (1997) called RCM2. The RCM process is considered by many to be a very effective and comprehensive maintenance process that can, if implemented correctly, improve reliability and plant availability substantially. However, many maintenance practitioners and maintenance experts who have used RCM will tell you that it is an overcomplicated process and that it is difficult to implement. In many cases the process is abandoned and left incomplete due to the amount of resources required and the slow initial results delivered by the process. This dissertation investigates the reason for this and considers the viability of implementing the RCM process on an industrial level. The Hot Strip Mill (HSM) at the ArcelorMittal Vanderbijlpark plant was used as a case study. The viability of using RCM to improve the HSM maintenance practices was investigated. A suggested maintenance improvement plan was developed that is more suitable for the HSM maintenance environment and culture.
MSc (Development and Management Engineering), North-West University, Potchefstroom Campus, 2015

The study explores South African respondents’ attitudes toward game meat and finds the differences between the attitudes of consumer and non-consumer respondents of game meat toward the following attributes of game meat: sensory characteristics; health benefits; game meat production ethics; animal welfare; safety for human consumption; availability; price; promotion; and preparation. This quantitative study determined the attitudes of 1096 consumers and 310 non-consumers of game meat with an online survey using questionnaires. Recruitment was done through social media and e-mail forwarding. The differences in attitudes between consumer and non-consumer respondents were determined using Fishbein’s attitude-toward-the-object model. Based on attitudes toward individual attributes, respondents classified some product attributes as important in their decision to consume, or not to consume, game meat. Respondents indicated that the availability, sensory characteristics, game meat production ethics and health benefits are considered to be important in their consumption of game meat. To market game meat purposefully, the industry should focus on these attributes.
Life and Consumer Sciences
MCS (Life and Consumer Sciences)

It is important that organisations are aware of factors that might affect the levels of well-being of employees, as employees are instrumental to the achievement of organisational goals. Well-being of employees can be conceptualised in terms of burnout and engagement. Studies have shown that different factors contribute to the employee experience of burnout and engagement. These factors include job demands and resources and psychological conditions (psychological meaningfulness, psychological availability and psychological safety). Although various studies regarding burnout and engagement can be found in literature, three research gaps have been identified from the studies. First, a reliable and valid instrument is needed to measure job demands and resources in a specific organisation. Second, given the cost of some measures of burnout, inadequacies in conceptualisation of the burnout construct and the inadequate psychometric properties of others, an inexpensive measure is needed which can be used to measure burnout in a valid and reliable way. Third, no studies seem to be found which focus on the effects of job demands and resources on burnout and engagement via specific psychological conditions (i.e. psychological meaningfulness, availability and safety). The general objective of this research therefore was to investigate the well-being of employees in a South African agricultural research organisation. It focused on job demands, job resources, burnout, work engagement and psychological conditions. The objective of the first study was to investigate the job demands and resources of employees in a South African agricultural research organisation. The study specifically examined the validity and reliability of a scale adapted to measure job demands and resources of the employees and established the prevalent job demands and resources of the employees. Differences that may exist based on the employees‟ demographic variables were also investigated. The aim of the second study was to provide an overview of current burnout measures that are used in the literature. From the literature, gaps were identified and used to develop a new Burnout Scale for use with employees within a South African agricultural research organisation. The research then examined the construct validity, reliability, construct equivalence and item bias of the newly-developed Burnout Scale. The research also investigated whether any differences in burnout existed in relation to the employees‟ demographic variables. The third study investigated the relationships between specific job demands, job resources, psychological conditions, burnout, and work engagement by testing a structural model of burnout and engagement in a sample of employees within a South African agricultural research organisation. The research method for each of the three articles consisted of a brief literature review and an empirical study. A non-probability availability sample of 443 agricultural employees was used. A cross-sectional design, with a survey as the data collection technique, was used. Measuring instruments that were utilised included an adapted Job Demands-Resources scale (AJDRS), a self-developed Burnout Scale (BS), a self-developed Work Engagement Scale (WES), an adapted Psychological Conditions Questionnaire (PCQ), and a biographical questionnaire. The statistical analyses were carried out with the help of the SPSS programme (IBM SPSS statistics, version 21) and MPLUS version 7.11 (Muthén, & Muthén 1998-2013). The statistical methods utilised in the three articles included descriptive statistics, Cronbach alpha coefficients, principal factor analysis, Pearson product-moment correlation coefficients, MANOVA, ANOVA, differential item functioning (DIF), and structural equation modelling. Evidence was established for the factorial validity and reliability of the AJDRS. The results indicate that the job demands experienced by employees in an agricultural research organisation are: overload and job insecurity; while job resources were: organisational support, growth opportunities, control, rewards, and physical resources (equipment). It was furthermore found that there were differences in the perceived job demands and resources of employees. In addition, the BS was found to consist of three reliable factors, i.e. fatigue, emotional exhaustion/withdrawal, and cognitive weariness. The results also showed construct equivalence for the Burnout construct, and no item bias for the language groups examined. Age was found to affect the level of perceived burnout of the employees. Furthermore, job resources (growth opportunities, control, and organisational support) were found to be positively associated with engagement, while lack of resources and job demands (overload) are positively associated with burnout of employees. Psychological meaningfulness, safety and availability are positively associated with work engagement, and negatively associated with burnout. The psychological conditions of availability, safety, and meaningfulness mediated the relationship between job resources and work engagement, as well as between lack of job resources and burnout. Psychological availability and meaningfulness mediated the relationship between job demands and burnout; however, the mediation effect of psychological safety on the relationship between job demands and burnout could not be established. Recommendations are made for practice, as well as future research.
PhD (Industrial Psychology), North-West University, Potchefstroom Campus, 2014

Certains phénomènes contemporains, comme le développement des technologies de communication, la mondialisation des marchés et l’intensification du travail ont perturbé de manière radicale le marché du travail. Ainsi, nous assistons à la transition entre une société industrielles caractérisée par des horaires prévisibles et stables, vers une société post-industrielle où les modes d’organisation des temps liés au travail sont flexibles et diversifiés et où il existe un brouillage des frontières entre le temps de travail et le temps personnel. Plusieurs études scientifiques ont établi des liens significatifs entre les modes d’organisation des temps liés au travail, par exemple les longues heures de travail, le temps supplémentaire obligatoire, le travail posté, l’obligation de disponibilité, les périodes de garde, les horaires de faction, le temps partiel et les périodes de pauses et de repos, et plusieurs problématiques de santé physique et psychologique. Il est donc légitime de se demander si l’ensemble législatif encadrant les rapports de travail au Québec, qui a été mis sur pied pendant la période industrielle, est toujours pertinent et adéquat pour soutenir l’un des objectifs qu’il porte, soit la protection de la santé et de la sécurité des travailleurs. Le but de notre recherche est de déterminer dans quelle mesure l’encadrement juridique actuel au Québec permet de protéger la santé et la sécurité des travailleurs exposés aux risques générés par les modes d’organisation des temps liés au travail. Afin d’atteindre notre objectif, nous avons examiné, par une étude empirique de la jurisprudence, l’encadrement juridique des différents modes d’organisation des temps liés au travail que nous avons retrouvés dans notre échantillon, soit le temps supplémentaire obligatoire, le travail posté, les horaires de faction, l’obligation de disponibilité, les périodes de pauses et de repos ainsi que les litiges relatifs à la grossesse et à l’allaitement. Nous nous sommes particulièrement intéressés à la question de la mobilisation des normes et des recours dans le contexte d’un système juridique morcelé. De manière générale, notre recherche démontre que le droit du travail souffre de plusieurs lacunes qui nuisent à la mobilisation des normes par les travailleurs, ce qui diminue la protection légale de leur santé et de leur sécurité et qui réduit l’accessibilité de la justice.
Contemporary phenomena such as the development of communication technologies, the globalization of markets and the intensification of work have radically disrupted the labour market. Thus, we are witnessing the transition from an industrial society characterized by predictable and stable working hours to a post-industrial society where the ways of organizing the work-related time are flexible and diversified, and in which the boundaries between working time and personal time are blurred. Several scientific studies have established significant links between the modes of organization of work-related time, such as long working hours, overtime, shift work, mandatory availability, on-call periods, faction schedules, part-time work, and break and rest periods, and several physical and psychological health issues. It is therefore legitimate to wonder whether the legislative framework governing Quebec’s labour market, which was instituted in the industrial era, is still relevant and adequate to achieve one of its aim, namely to protect the worker’s occupational health and safety. The purpose of our research is to determine the extent to which the current legal framework in Quebec allows for the protection of the health and safety of workers exposed to risks generated by the organization of work-related time. We have examined, through an empirical study of case law, the legal framework surrounding the different ways of organizing work time that we identified in our sample, such as mandatory overtime, shift work, faction schedules, mandatory availability, rest and break periods and disputes related to work time for pregnant or breastfeeding workers. We were particularly interested in the issue of mobilizing norms and recourses in the context of a fragmented legal system. Overall, our research demonstrates that the labour legal framework suffers from important shortcomings, which impede the mobilization of the rules by workers, thereby radically diminishing the legal protection of the workers’ occupational health and safety and raising significant concerns about the accessibility to justice.

Ethnic food markets and restaurants are the main source of immigrants’ traditional foods in South Africa. Despite this, the actual availability and accessibility of ethnic foods from the ethnic food markets and restaurants has not been investigated. Furthermore, factors that influence the role of ethnic foods in the diets of immigrants, like perceptions of Sub-Saharan Immigrants towards South Africa food culture, and the safety of ethnic foods have not been established. Although a number of studies have been conducted on the identification of microbial hazards of cooked food in the informal sector, none have been conducted on ethnic foods of Sub-Saharan Immigrants. Aim and objectives The aim of this study was to assess the availability and accessibility of Sub-Saharan African immigrants’ traditional food from ethnic food markets, shops and restaurants, establish immigrants’ perceptions towards South African’s food culture, and determine predictors of contamination of selected cooked food sold in the ethnic food markets, and restaurants. From this aim, eight objectives were formulated as follows: (i) describe the immigrants’ perceptions towards South Africa’s food culture, (ii) investigate the contribution of the ethnic food markets on the dietary patterns of immigrants, (iii) investigate the availability, and accessibility of the ethnic foods available in the ethnic food markets, and restaurants, (iv) document coping strategies adopted by immigrants when faced with shortage of their traditional foods or ingredients in South Africa (v) identify factors associated with a move away from their ethnic foods and adoption of South African foods, (vi) investigate the microbiological quality of selected cooked foods found in the ethnic food markets and restaurants, and (vii) investigate predictors of contamination of ethnic foods bought from the restaurants and markets. A cross-sectional research design using a mixed methods approach was adopted to achieve the objectives of this study. The mixed method employed three instruments, namely: questionnaire, checklist, and laboratory microbial analysis. The study was conducted in Tshwane and Johannesburg metropolitan municipalities. The study focused on two study populations: (i) immigrant households from West, East and Central Africa regions, and ii) entrepreneurs selling Sub-Saharan ethnic ready-to-eat (RTE) foods. The snowball sampling method was adopted to sample both study populations. A total of one hundred and ninety four (n=194) women and forty (n=40) entrepreneurs who met the inclusion criteria and agreed to participate were included in the study. A checklist was employed to assess restaurants and vending sites. Two samples of RTE ethnic foods were collected from each entrepreneur and submitted to the microbiology laboratory at the Council for Scientific and Industrial Research (CSIR). Data obtained from the questionnaire, checklist and microbial analysis were analysed, and descriptive statistics were presented as tables and figures. Multivariable and binary logistic regression models were fitted to the data to assess predictors of adoption and contamination respectively. Results Ethnic foods still featured prominently in the diets of immigrants, with only 7.7 % (n=15) indicating that they strictly followed a South African diet. Ethnic food markets are the main sources of ethnic foods for immigrants living in Gauteng. Efforts to maintain ethnic diets by Sub-Saharan immigrants resident in South Africa are hindered by factors such as unaffordability (39.2%;n=76) and unavailability (25.3%; n=49) of their ethnic foods. Meanwhile, relying on less preferred food (38.7%; n=75) and replacing unavailable ingredients with similar ingredients (37.6%; n=73%) were identified as two main coping strategies that are adopted by immigrants when facing unavailability of their traditional food ingredients. Four patterns of dietary acculturation were identified, namely, strict continuity with traditional foods (21.6%; n=42), very limited adoption (21.1 %; n=39), limited adoption (50.5%; n=98) and complete adoption (7.7%; n=15) of South African foods. The following were the most common food items that the respondents tended to adopt: pap (84.5%; n=164); fried potato chips (43.8%; n=85); cold drinks (42.8%; n=83); fast foods (37.6%; n=73); sphathlo (30.9%; n=60); and vetkoek (30.4%; n=59). Four factors that were associated with adoption of South African foods included:  spending R2500-R3499 (OR 3.34; p=0.017) and 3500-4500 (OR 3.99; p=0.030) on food,  residing in the country between 3-6 years (OR 5.16; p=0.001),  earning between 5000-10 000 (OR 0.52; p=0.040) and >R11 000 (OR 0.380; p=0.057), and  being in part-time/temporary employment (OR 5.85; p=0.025). The majority of the ethnic food entrepreneurs were West Africans (70%; n=28), belonging mainly to the 30-49 years old age group (88%; n=35). Over 35%% (n=14) of the entrepreneurs indicated that they had completed high school education, while 42.5% (n=17) had tertiary education. The majority (80%, n= 34) of vendors of ethnic foods did not have a certificate in food handling or hygiene practices. The majority (95%, n=38) of entrepreneurs operated in permanent structures with ceilings and walls. A majority (95%; n=38) also had access to tap water and flushing toilets. However, ownership of appliances such as thermometers (0%, n=0), microwaves (55%, n=22), and freezers (37.5%, n=15) was very low. There was also low adherence with regards to the following aspects: wearing of protective clothing such as caps (40%; n=24), apron (62.5%, n=25) and gloves (0%, n=0); not wearing jewellery (50%; n=20); keeping fingernails short and clean; and proper reheating of food. Samples contaminated with total viable counts above the threshold of satisfactory counts (<10⁵ CFU/g) was very high (71.3% , n=57). Over twenty percent (22.5%; n=18) of the food samples had unsatisfactory levels of coliforms (>10 ³ CFU/g), and 17.5% (n=14) had unsatisfactory levels (>3 CFU/g) of E. coli. Salmonella was observed in only 3.8 % (n=3) food samples. Being new in business (OR=0.010, p=.033), owning a freezer (OR .477; p= .052), not owning a microwave (OR .013, p=.074), and reheating per serving (OR .187, p=.048) were identified as significant drivers of contamination. Conclusion In the two metropolitans that were investigated only 40 vendors of ethnic foods could be identified. This number is too low to be able to supply the whole immigrant community with ethnic foods. Thus their role as a contributor to household food security is limited. As a result, although the majority of immigrants attempt to preserve their traditional diets, high ethnic food prices and unavailability of traditional ingredients forces them into bicultural eating patterns. Although bicultural eating patterns are supposed to protect against food insecurity, the adoption of unhealthy dietary habits and could render them vulnerable to food insecurity. Lack of knowledge of South Africa foods results in poor food choices. In the long run these unhealthy eating patterns could have negative implications choices. In the long run these unhealthy eating patterns could have negative implications on the nutritional health of immigrants and the health system of South Africa. Therefore, studies to identify foods with similar taste and nutritious ingredients could aid prevention of obesity and lifestyle diseases and inform culture-specific nutrition education programmes. The high number of entrepreneurs without training on food hygiene and handling practices limits the role of the ethnic restaurants in the food security of immigrants living in Gauteng, and food quality is thus compromised. Therefore, there is a need for targeted training programmes which cater for the unique needs of the ethnic entrepreneurs to enable them to play a meaningful role in ensuring that immigrants who want to maintain their food culture are food secure. These programmes should also address the poor handling and hygiene practices that were observed in this study. This could be done by emphasising the World Health Organization’s (WHO) five keys to safer food. Results of the food contamination indicate that entrepreneurs are able to produce safe food, (as supported by only moderate contamination levels of coliforms and E. coli, which also suggests low risk of environmental and enteric contaminants). However, if these concerns are not addressed immediately by proper training and monitoring, they could further compromise the role played by ethnic food markets in food security. Training and monitoring programmes should place more emphasis on the four factors that were identified as drivers of contamination
Agriculture, Animal Health and Human Ecology
Ph. D. (Agriculture)