Fruit flies (Tephritidae) can enter and establish in new territories due to the movement of fruit from one area to another through trade or tourism, which can negatively impact on fruit production and market access. An invader fruit fly species (Bactrocera invadens) has established on the African continent and has spread throughout sub-Saharan Africa. This newly described polyphagous fruit fly species is a successful invader species which continues to distribute and establish in new habitats. The introduction and establishment of B. invadens in South Africa may have serious market access consequences with regard to fruit exports due to its absence in the territories of many trading partners. The Musina area was considered as the study area as it is the first entry point from Zimbabwe. The national highway (N1) which runs through the area is a major route from several B. invadens infested countries in the Southern Africa region. A species initiated pest risk assessment was conveyed to determine the risk potential of this pest. The pest risk assessment (PRA) identified several pathways with a high risk to the Musina area, that B. invadens can follow. A detection survey was carried out to determine the status of B. invadens in the Musina area as support to the PRA. The detection survey continued over three years and by the second year B. invadens was detected for the first time in the study area. The detection survey was followed by a delimiting survey and the pest was eradicated in the area. After several months of no detection, it was however detected again in the area. Risk management options were suggested for regulatory control as an outcome of the pest risk assessment. These measures can be utilised by the National Plant Protection Organisation of South Africa for the commercial importation of host material of B. invadens, control of fruit imported by travellers, informal traders and national control in the event of pest incursions in the area. Corrective actions as well as quarantine actions should be implemented in an integrated approach in the affected areas. / Thesis (Master of Environmental Sciences)--North-West University, Potchefstroom Campus, 2013.

Thesis (M. Ed.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 134-141).

Thesis (M.Ed.)--University of Hong Kong, 1996. / Includes bibliographical references (leaves 134-141). Also available in print.

The teaching and learning of Environmental Education as an integrated approach to education and training aims at a holistic modality. This requires a commitment by stakeholders to support formal and informal Environmental Education implementation. By means of descriptive qualitative and quantitative methods, I investigated local, national and global, past and present Environmental Education practices with a view to recommend criteria for a model for the integration of Environmental Education into the school curriculum of the Northern Province. The findings revealed that various countries have attempted to address the position and status of Environmental Education in the school curriculum. The one subject approach and a cross-curriculum approach emerge consistently as the options adopted. Neither of the two approaches are cited as completely successful. The integrated nature of Environmental Education issues are countered by country systemic constraints, for example the political climate, among other things. Other impediments to implementing Environmental Education are policy makers' lack of knowledge and negative attitudes, lack of resources, curriculum design deficiencies, inadequate pre-service and in-service teacher training and misconceptions about Environmental Education. The history, principles and the peculiarities of Environmental Education, the lessons learnt from other countries and the empirical investigation in the Northern Province give indicators that form the basis of the model recommended by this research. In view of the findings the recommendation is made that Environmental Education be integrated into the school curriculum of the Northern Province for General Education and Training and Further Education and Training for all school grades using a project approach, a discipline-specific thematic approach and as a discipline. / Educational Studies / D. Ed (Didactics)

The European General Data Protection Regulation (GDPR) will soon come into force, it is a regulation which spells out increased compliance demands for data protection by design. Failure to comply can lead to huge financial penalties, something IT companies controlling and processing personal data should not ignore. As the one-year countdown begins, studies have revealed under-preparedness of organizations affected by the GDPR. None of the studies so far has offered an integrated overview of the barriers faced by IT companies to embrace data protection by design. This study aims to help fill this gap and to investigate. A study based on expert’s knowledge has been carried out, using an integrated approach. Five experts from advocacy, legal and IT industry were interviewed, aiming to answer the following research question: “What are the barriers for IT companies to embrace data protection by design and how should these barriers be overcome?” An integrated overview of the barriers will then be presented, which includes the managerial, engineering and legal obstacles. The study goes on to present pathways to embrace data protection by design. A key contribution to this study is that managerial, legal and engineering barriers have shown to be directly interconnected and influence on each other. As such a much broader view must be undertaken to fully understand the different barriers that face IT companies in embracing data protection by design.

L'évaluation de l'impact écologique d'une exposition aux rayonnements ionisants est devenue une préoccupation majeure. L'objectif de ce doctorat était d'étudier les effets multigénérationnels d'une irradiation gamma chronique selon une approche intégrée, des traits d'histoire de vie aux mécanismes subcellulaires chez un organisme modèle, le nématode Caenorhabditis elegans. L'étude des effets d'une irradiation gamma chronique sur les traits d'histoire de vie de C. elegans a d'abord été effectuée. Pour cela, trois générations ont été exposées et deux générations ont été placées en environnement « contrôle » après exposition parentale. Puis, différents mécanismes subcellulaires pouvant expliquer les effets observés sur les traits d'histoire de vie ont été par la suite caractérisés. Les résultats obtenus ont mis en évidence que (i) la reproduction était le critère d'effet le plus sensible, (ii) une augmentation de la radiosensibilité était observée sur trois générations exposées et (iii) les effets de la génération parentale étaient transmis aux générations non-exposées. Une augmentation de l'apoptose, une diminution du stock de spermatozoïdes et du nombre de cellules mitotiques semblent expliquer la diminution de la reproduction dans les générations exposées. Seule une diminution du nombre de spermatozoïdes a été observée en parallèle d'une diminution de la reproduction dans les générations placées non exposées. Ce projet de recherche a permis d'apporter des connaissances sur les effets multigénérationnels d'une irradiation gamma et montre l'intérêt d'utiliser une approche intégrée pour mieux comprendre les mécanismes d'action liés à l'action d'un polluant. / The environmental risk assessment of chronic exposure to ionizing has become a major concern. The aim of this PhD was to study the multigenerational effects of chronic gamma radiation in an integrated manner (to the life history traits from the subcellular mechanisms) in a model organism, the nematode Caenorhabditis elegans. First, studying the effects of chronic gamma radiation on the life history traits of C. elegans was performed. For that, three generations have been exposed to different dose rates and two generations have been placed in "control" environment after parental exposure. The second part of this thesis aimed to characterize the different subcellular mechanisms that could explain the observed effects on the life history traits after multigenerational exposure. The results showed that (i) the reproduction was the most sensitive endpoint to gamma radiation, (ii) an increase in radiosensitivity was observed over three exposed generations and (iii) the effects of the parental generation were transmitted to the non-exposed generations. An increase in apoptosis, a reduction in the stock of sperm, and to a lesser extent, a decrease in the number of mitotic cells, could explain the observed decrease in reproduction for the exposed generations. Only a decrease in sperm number was observed in parallel with a reduction in the cumulative number of larvae in the non-exposed generations. This research contributes to our knowledge on the multigenerational effects of gamma irradiation and shows the importance of an integrated approach to better understand the mechanisms of action related to the action of a pollutant and improve the environmental risk assessment.

Cette thèse s’intéresse aux réseaux de confusion comme représentation compacte et structurée des hypothèses multiples produites par un moteur de reconnaissance de parole et transmises à un module de post-traitement applicatif. Les réseaux de confusion (CN pour Confusion Networks) sont générés à partir des graphes de mots et structurent l’information sous la forme d’une séquence de classes contenant des hypothèses de mots en concurrence. Le cas d’usage étudié dans ces travaux est celui des hypothèses de reconnaissance transmises à un module de compréhension de la parole dans le cadre d’une application de dialogue déployée par France Telecom. Deux problématiques inhérentes à ce contexte applicatif sont soulevées. De façon générale, un système de dialogue doit non seulement reconnaître un énoncé prononcé par un utilisateur, mais aussi l’interpréter afin de déduire sons sens. Du point de vue de l’utilisateur, les performances perçues sont plus proches de celles de la chaîne complète de compréhension que de celles de la reconnaissance vocale seule. Ce sont ces performances que nous cherchons à optimiser. Le cas plus particulier d’une application déployée implique de pouvoir traiter des données réelles et donc très variées. Un énoncé peut être plus ou moins bruité, dans le domaine ou hors-domaine, couvert par le modèle sémantique de l’application ou non, etc. Étant donnée cette grande variabilité, nous posons la question de savoir si le fait d’appliquer les mêmes traitements sur l’ensemble des données, comme c’est le cas dans les approches classiques, est une solution adaptée. Avec cette double perspective, cette thèse s’attache à la fois à enrichir l’algorithme de construction des CNs dans le but d’optimiser globalement le processus de compréhension et à proposer une stratégie adéquate d’utilisation des réseaux de confusion dans le contexte d’une application réelle. Après une analyse des propriétés de deux approches de construction des CNs sur un corpus de données réelles, l’algorithme retenu est celui du "pivot". Nous en proposons une version modifiée et adaptée au contexte applicatif en introduisant notamment un traitement différencié des mots du graphe qui privilégie les mots porteurs de sens. En réponse à la grande variabilité des énoncés à traiter dans une application déployée, nous proposons une stratégie de décision à plusieurs niveaux qui vise à mieux prendre en compte les spécificités des différents types d’énoncés. Nous montrons notamment qu’il est préférable de n’exploiter la richesse des sorties multiples que sur les énoncés réellement porteurs de sens. Cette stratégie permet à la fois d’optimiser les temps de calcul et d’améliorer globalement les performances du système / The work presented in this PhD deals with the confusion networks as a compact and structured representation of multiple aligned recognition hypotheses produced by a speech recognition system and used by different applications. The confusion networks (CN) are constructed from word graphs and structure information as a sequence of classes containing several competing word hypothesis. In this work we focus on the problem of robust understanding from spontaneous speech input in a dialogue application, using CNs as structured representation of recognition hypotheses for the spoken language understanding module. We use France Telecom spoken dialogue system for customer care. Two issues inherent to this context are tackled. A dialogue system does not only have to recognize what a user says but also to understand the meaning of his request and to act upon it. From the user’s point of view, system performance is more accurately represented by the performance of the understanding process than by speech recognition performance only. Our work aims at improving the performance of the understanding process. Using a real application implies being able to process real heterogeneous data. An utterance can be more or less noisy, in the domain or out of the domain of the application, covered or not by the semantic model of the application, etc. A question raised by the variability of the data is whether applying the same processes to the entire data set, as done in classical approaches, is a suitable solution. This work follows a double perspective : to improve the CN construction algorithm with the intention of optimizing the understanding process and to propose an adequate strategy for the use of CN in a real application. Following a detailed analysis of two CN construction algorithms on a test set collected using the France Telecom customer care service, we decided to use the "pivot" algorithm for our work. We present a modified and adapted version of this algorithm. The new algorithm introduces different processing techniques for the words which are important for the understanding process. As for the variability of the real data the application has to process, we present a new multiple level decision strategy aiming at applying different processing techniques for different utterance categories. We show that it is preferable to process multiple recognition hypotheses only on utterances having a valid interpretation. This strategy optimises computation time and yields better global performance

Please read the abstract in the section 00front of this document / Thesis (DMus)--University of Pretoria, 2010. / Music / unrestricted

Le sujet de thèse porte sur la planification tactique et opérationnelle d’une chaîne logistique dans un contexte dynamique. Nous proposons un modèle de planification basé sur une structure décisionnelle à deux niveaux. Adoptant un processus dynamique permettant d’actualiser les données à chaque étape de planification, le premier niveau planifie la production en recherchant le meilleur compromis entre les leviers décisionnels disponibles liés aux aspects capacité et coût de production. Le deuxième niveau établit un ordonnancement agrégé des opérations de fabrication en minimisant les en-cours. Le recours à une structure décisionnelle intégrée nous a conduit à établir une interaction entre les niveaux supérieur et inférieur de décision, mise en oeuvre par des contraintes dites de conservation d’énergie. Notre approche est modélisée sous la forme d’un problème de satisfaction de contraintes (CSP, Constraint Satisfaction Problem) et évaluée par simulation dans un contexte de données incertaines. Nous avons mené différentes expérimentations portant sur la variation de la demande, la variation de la capacité et la re-planification de la demande. Toutes les expérimentations sont réalisées par deux méthodes de résolution différentes : une méthode basée sur un CSP statique et une méthode basée sur un CSP dynamique. La performance d’une solution de planification/ordonnancement est renseignée par l’ensemble des mesures de la stabilité et de la robustesse. Les expérimentations réalisées offrent une démonstration de la performance de la méthode de résolution basée sur un CSP dynamique par rapport à la méthode statique / This work focuses on the supply chain operational and tactical planning problem in an uncertain environment. We propose a tactical planning model, based on a two-level decisional structure. Adopting a dynamic process, which enables data updating at each planning step, the first level performs a plan by searching for the best compromise between available decision-making levers for production costs and capacity. The second level establishes an aggregate scheduling of production tasks by minimizing the total weighted completion time. The use of an integrated decision structure involves interaction between the upper and lower decision levels constraints, implemented by constraints known as energy conservation constraints. Our approach is formulated according to a constraint satisfaction problem (CSP) and evaluated by simulation under uncertain data. For this, we have developed various experiments related to the variation of customer demand, resource capacity, and the re-planning of demand. All the experiments are carried out by two different methods : a method based on a static CSP and a method based on a dynamic CSP. The performance of a scheduling/planning solution is reported through a set of robustness and stability measurements. Results of experiments confirm the performance of the method based on a dynamic CSP

Finding the proper balance between availability and cost efficiency is an important concern within spare part management. Spare part suppliers need to respond quickly to customer demand as a stock-out can have severe consequences for both the customer and the supplier. It is critical to identify what items to keep in stock and where to allocate the inventory to avoid stock-outs. This case study was performed at a large high-tech company producing manufacturing equipment to be used in the electronics industry. The aim was to lower the stock-levels of spare parts while not impairing the availability by combining item classification, demand forecasting, and distribution network optimization. A decision diagram for classifying spare parts was constructed using the analytical hierarchy process. Twenty items were classified using the diagram, and the demand for them was forecasted using the Syntetos Boylan Approximationmethod. The shipping cost for spare parts within one region was minimized using a linear optimization model. The analysis showed that equipment criticality, annual usage value, and installed base are critical when classing spare parts. Instead of using five distribution centers in the European region, it was discovered that the shipping costs would decrease if only three warehouses made up the distribution network. The spare parts investigated appeared to follow the typical characteristics for spare parts, showing a low and irregular demand. Hence, demand forecasting seemed to be unnecessary, considering the difficulties in getting satisfactory results. Instead of combining the results from classification, forecasting, and inventory allocation, we suggest that the processes affecting stocking decisions should cooperate and work towards a common objective, namely to satisfy the customer demand in a cost-efficient way. Thus, widening the meaning of taking on an integrated approach to spare part management. / Inom hanteringen av reservdelar är det en stor utmaning att hitta rätt avvägning mellan tillgänglighet och kostnadseffektivitet. Leverantörer av reservdelar måste snabbt kunna möta kundefterfrågan eftersom uteblivna leveranser av kritiska reservdelar kan få allvarliga konsekvenser för både kund och leverantör. Vilka artiklar som ska lager-hållas och var de ska lagerhållas är avgörande beslut för att undvika att artiklar rest-noteras. I den här fallstudien, som utfördes på ett stort teknikföretag som tillverkarproduktionsutrustning till elektronikindustrin, var syftet att sänka lagernivåerna av reservdelar utan att göra avkall på tillgängligheten. Detta genom att kombineragruppering av artiklar, beräkning av kommande efterfrågan och optimering av distributionsnätverket. För att klassificera artiklar i grupper med liknande egenskaper skapades ett schematiskt beslutsdiagram med hjälp av metoden AHP. Tjugo artiklar ur sortimentet valdes ut som beslutsdiagrammet testades på. För samma tjugo artiklar gjordes prognoser för den kommande efterfrågan med metoden Syntetos-Boylan-Approximation. Distributionsnätverket i den europeiska regionen optimerades medavseende på fraktkostnad genom att applicera en linjär optimeringsmodell. Hur kritisk en reservdel är för den relaterade maskinens funktionalitet, reservdelensårliga förbrukningsvärde och den geografiska placeringen av installerade maskinervisade sig vara kritiska för att kunna klassificera artiklarna effektivt. Analysen av distributionsnätverket i Europa visade att fraktkostnaderna kan minskas om nätverket utgjordes av tre lager istället för fem som det gör i dagsläget. De tjugo undersökta reservdelarna uppvisade de typiska egenskaperna för reservdelar som har rapporterats i litteraturen som låg och oregelbunden efterfrågan. Att sätta prognoser på efterfrågan verkar obefogat med tanke på komplexiteten i beräkningarna och att de ger få tillfredsställande resultat. Istället för att kombinera resultaten från klassificering, prognoser på efterfrågan och lageroptimering föreslår vi att alla de funktioner i ett företag som arbetar med att tillgodose kundefterfrågan bör samarbeta i högre grad och jobba mot ett gemensamt mål, nämligen att tillgodose kundernas efterfrågan på ett kostnadseffektivt sätt. Således vill vi utvidga betydelsen av att ta en integrerad strategi för reservdelshantering