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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Optimisation intégrée des décisions en planification et ordonnancement dans une chaîne logistique / Integrated optimization of planning and scheduling decisions in a supply chain

Gomez Urrutia, Edwin David 12 June 2014 (has links)
Dans cette thèse, nous étudions l’optimisation des problèmes de planification et d’ordonnancement des flux, dans une stratégie d’intégration des décisions, pour planifier la chaîne logistique au niveau tactique avec prise en compte de contraintes opérationnelles. Le but de ce travail est de répondre au besoin de cohérence entre les décisions de planification et d’ordonnancement, qui sont souvent prises de manière séquentielle ne garantissant pas la faisabilité des plans de production. Nous proposons une approche intégrée pour résoudre des problèmes mono-niveau et multi-niveaux, dans des systèmes multi-produits et multi-ressources dans des ateliers de type job-shop.Les problèmes de planification avec contraintes de capacité et les problèmes d’ordonnancement dans des systèmes complexes sont des problèmes NP-difficiles. Intégrer les contraintes propres aux deux problèmes engendre un nouveau problème qui est d’autant plus complexe. Nous proposons une décomposition du problème intégré en un ensemble de sous-problèmes de planification avec séquence fixée, résolus par relaxation Lagrangienne. L’amélioration de la séquence est guidée par une recherche taboue. L’efficacité de l’approche intégrée, par rapport à un solveur commercial, a été prouvée en termes de qualité des solutions et d’effort de calcul. Pour les problèmes multi-niveaux, nous proposons une nouvelle formulation basée sur la notion d’échelon stock, ainsi que de nouveaux algorithmes et stratégies de lissage de la production, pour construire des plans de production respectant les contraintes de capacité détaillées et de nomenclature / In this thesis, we study the optimization of flow planning and scheduling, within a strategy to integrate decisions for supply chain planning at tactical level, taking into account operational constraints. The goal of this work is to address the need for consistency between decisions arising from production planning and scheduling. These decisions are often taken in a sequential order, leading most of the time to unfeasible production plans. We propose an integrated approach to solve single-level and multi-level problems in multi-item multi-resource systems configured as job-shops.Both capacitated production planning and scheduling problems, in complex manufacturing systems, are NP-hard. Therefore, integrating constraints of both problems generates a new problem which is even more difficult to solve. We propose a decomposition of the integrated problem into a set of several sub-problems with fixed sequence, solved by Lagrangian Relaxation. The sequence improvement is guided by a Tabu Search. The efficiency of the integrated approach comparing to a standard solver is proved in terms of solution quality and computational effort. In case of multi-level problems, we propose a new mathematical model based on the concept of echelon stock, as well as new algorithms and smoothing strategies to build production plans respecting detailed capacity and bill-of-materials constraints.
32

Criteria for a model for the integration of environmental education into the school curriculum of the Northern Province

Rampedi, Moshibudi Priscilla 11 1900 (has links)
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)
33

Risk management in liquefied natural gas ports and marine terminals supply chains

Briouig, Mohamed January 2014 (has links)
Due to its environmental attributes, Liquefied Natural Gas (LNG) as a clean fossil fuel source of energy has witnessed a steady increase in demand worldwide over the last decade. This increase is mainly attributed to higher demand from the power generation sector as well as from domestic and industrial usages .This growing role of LNG among competing energy sources has raised concerns over the safety and security of the LNG chain of production, transport and distribution and its related infrastructure. Within this context, LNG ports and marine terminals, being strategically located at the midstream of the LNG Supply Chain (SC), are further exposed to safety and security risks and represent credible targets for international terrorism. Ensuring uninterrupted, robust and resilient LNG SC requires first, adequate management of safety and security risks in LNG ports and marine terminals. While each discipline of risk, be it safety or security, has received significant attention both in theory and practice, less attention was given to the management of interfaces and shared impacts among LNG Ports safety and security risks which led to the existence of gaps in the risk management (RM) systems of LNG ports and may represent a major source of risk and disruption to LNG ports. This research addresses such gaps which are poorly addressed in the current literature and proposes a holistic and integrated approach to the issues of LNG ports safety and security risks assessment and management. It also aims to model safety and security RM from a SC perspective and examines the relationships and shared impacts among LNG ports safety and security risks in the present context of increased LNG demand worldwide in the post 9/11 terrorism era. A unique combination of multiple methods within port and maritime SCs, including a Delphi survey, quantitative survey, Soft Systems Methodology (SSM) and a focus group expert consultation, is applied to reformulate the prevailing RM approach marked by dichotomy and a disciplinary silo and to propose a more enhanced and holistic approach to safety and security RM. The results of the study confirm that an integrated and holistic approach to the issue of RM in LNG ports and marine terminals is necessary to cost-effectively address safety and security risks and ensure reliable and resilient LNG SCs. Furthermore, a practical framework, in the form of a conceptual model, for LNG ports risks and emergencies management is proposed which integrates all facets of safety and security risks and emergencies management, including risk prevention, mitigation, emergency planning and response and port business continuity. The proposed conceptual model shows how the proposed RM approach can be practically applied in the context of LNG ports in the Middle East and North Africa (MENA) region, as well as in any LNG port worldwide which lacks an integrated approach to risks and emergencies management.
34

Fonctionnement, biodiversité, structure et dynamique des communautés végétales des zones humides temporaires de la région des Mogods, Tunisie septentrionale / Fonctionning, biodiversity, structure and dynamics of plant communities of temporary wetlands of Mogods region, Northern Tunisia

Ferchichi Ben Jamaa, Hafawa 16 December 2010 (has links)
Dans le contexte du déclin général des zones humides temporaires méditerranéennes et du manque de connaissances à leur sujet en Tunisie, l'étude pluridisciplinaire et multiscalaire de leur structure et de leur fonctionnement a été entreprise dans les Mogods (Tunisie septentrionale). (1) A l'échelle régionale, l'inventaire et la typologie de ces milieux permettent d'en définir les enjeux conservatoires. Ces résultats montrent, d'une part l'intérêt biogéographique majeur de la zone d'étude, qui abrite des milieux rares et exceptionnels (zones tourbeuses, lacs semi-permanents, Garâa Sejenane), et d'autre part sa diversité spécifique et biocénotique reflétant l'hétérogénéité spatiale des conditions hydrologiques et pédologiques. (2) A l'échelle paysagère, l'étude des communautés végétales de trois mares temporaires permet de caractériser leur composition, leur structure et leur dynamique intra- et interannuelle, et de montrer l'influence majeure du pâturage. Les résultats obtenus mettent en évidence la nécessité d'une politique de gestion intégrant le maintien de l'hétérogénéité paysagère et le fonctionnement des zones humides en métapopulations. (3) A l'échelle locale, l'étude d'une espèce rare récemment découverte en Tunisie (Pilularia minuta) permet de caractériser pour la première fois la morphologie de ses organes reproducteurs, de mettre en évidence l'ancienneté de sa présence locale, de confirmer son caractère pionnier et d'évaluer sa dépendance vis-à-vis des conditions hydrologiques.Les résultats obtenus révèlent la diversité, la richesse et l'importance conservatoire des zones humides temporaires des Mogods, presque totalement méconnues et ignorées à l'heure actuelle. Ils mettent en évidence leur vulnérabilité face au développement socio-économique de la région, et soulignent l'urgence de développer une gestion conservatoire rationnelle, adaptée et durable, à différents niveaux d'organisation (région, commune, site). / In the context of the general decline of Mediterranean temporary wetlands and of the lack of knowledge about them in Tunisia, the pluridisciplinary and multi-scale study of their structure and functioning has been undertaken in the Mogods region (N. Tunisia). (1) At the regional scale, the survey and the typology of these habitats allow defining the conservatory stakes. These results show, first the major biogeographical interest of the study zone, which harbours rare and exceptional wetlands (peaty zones, semi-permanent lakes, Garâa Sejenane), and second its species and community diversity that reflects the spatial heterogeneity of hydrological conditions and soils. (2) At the landscape scale, the study of plant communities of three temporary pools allows characterising their composition, structure, and intra- and inter-year dynamics, and to show the major influence of grazing. The obtained results highlight the need for a management policy i ntegrating the conservation of the landscape heterogeneity and the pools' functioning in metapopulations. (3) At the local scale, the study of a rare species recently discovered in Tunisia (Pilularia minuta) allows characterising for the first time its reproduction organs, revealing its ancient local origin, confirming its pioneer character, and evaluating its dependence on hydrological conditions.The obtained results highlight the diversity, the richness and the conservatory importance of temporary wetlands of Mogods region, today almost completely unknown and ignored. They reveal their vulnerability to the socio-economical development of the region, and underline the urgency to develop a rational, adapted and sustainable conservatory management at different organisation levels (region, city, site).
35

Transferts dans les systèmes emballage/aliments : structuration à façon de matériaux multicouches pour l’emballage sous atmosphère modifiée des produits frais / Mass transfers in food/packaging systems : Structuring tailor-made multilayer materials for modified atmosphere packaging of respiring produce

Cagnon, Thibaut 13 November 2012 (has links)
Malgré l'ampleur que prend la technologie sous atmosphère modifiée pour le conditionnement des fruits et légumes frais, l'adéquation des matériaux d'emballage avec les besoins des produits est insuffisante. D'une part parce que la conception de ces emballages repose encore sur des approches empiriques de type essai-erreur, et d'autre part parce que la plupart des matériaux disponibles sur le marché présentent des propriétés de transfert aux gaz trop restreintes compte tenu de la gamme de propriétés nécessaire pour couvrir les besoins de ces produits. En vue d'apporter des solutions à ces deux verrous, les travaux de thèse ont porté sur :-la mise en place et la validation d'une approche basée sur l'ingénierie reverse visant à identifier les propriétés de transfert requises ou cibles pour un végétal donné ;-l'étude des procédés de structuration à différentes échelles pour moduler les propriétés de transferts de papiers enduits de protéines de blé, issus de ressources renouvelables.Une démarche d'ingénierie reverse organisée en 5 étapes dont l'identification des besoins des produits et la prédiction des propriétés de transferts requises a été proposée et validée à travers la conception d'un papier enduit actif pour l'emballage sous atmosphère modifiée adapté à la conservation de fraises. Les différents procédés de structuration étudiés ont permis de produire des matériaux couvrant des gammes de permsélectivité allant de 5 à 18 et de perméance à l'oxygène allant de 0,02x10-10 à 2x10-10 mol.Pa-1.m-2.s-2, ce qui répond parfaitement aux besoins d'une sélection représentative de produits frais respirant. Que ce soit des papiers enduits par des procédés conventionnels (couche épaisse) ou des procédés innovants (nano-structuration couche par couche en présence de feuillets d'argile, montmorillonites), il est possible de moduler les propriétés de transferts aux gaz des papiers enduits soit en jouant sur le raffinage des papiers supports, le nombre de paires de couche (gluten/montmorillonite), ou encore en soumettant les matériaux ainsi obtenus à un balayage gazeux de CO2. Cette nouvelle approche et l'efficacité des matériaux protéiques à couvrir les besoins des fruits et légumes ouvrent la voie à la conception de nouveaux emballages mieux adaptés aux produits respirant. / Despite the growing importance of the modified atmosphere packaging (MAP) technology for fresh fruits and vegetable preservation, the adequacy of the packaging materials with the produce needs remains a problem. On one hand because the packaging development approaches are still based on empirical trial and error methods, and on the other hand, because of the non-adequate gas transfer properties (too restricted to cover the large game of gas transfer properties required) of the vast majority of conventional synthetic plastics currently used for fresh food packaging. In order to overcome these hindrances, the thesis work was split on two parts:-the establishment and the validation of a new approach based on reverse engineering aiming to identify the optimal (targeted) properties for optimal preservation of a selected produce;-the study of the various structuration processes at different scales to modulated the gas transfer properties of bio-sourced wheat gluten coated papers.The new reverse engineering approach for MAP conception consisted in 5 steps including the definition of the produce needs and the prediction of the optimal gas transfer properties of the packaging, and was validated through the conception of an active optimal packaging for strawberry preservation. The different structuration processes studied allowed production of a gluten based materials able to cover ranges of permselectivity and oxygen permeations going from 5 to 18 and 0.02x10-10 à 2x10-10 mol.Pa-1.m-2.s-2, which perfectly matched the needs of a representative selection of fresh produce. Be it for conventional coating techniques (thick layer) or innovative processes (layer-by-layer nano-structuring of gluten/montmorillionites layers), it was possible to modulate the transfer properties of coated papers by changing the refining degree of the support paper, the number of layer pairs (gluten/montmorillionites) deposited, or even by submitting such materials to a CO2 treatment.This new approach and the efficiency of the protein-based materials for covering the fresh fruits and vegetable needs open the way for conception of new optimal packaging for respiring produces.
36

The Assessment Criteria Of Urban Regeneration Projects: The Case Of The Fener-balat Districts In Istanbul

Duzcu, Seda 01 March 2006 (has links) (PDF)
Urban regeneration has become a frequently and widely used urban transformation strategy in many cities since the beginning of the 1990s. A number of urban regeneration projects have been implemented in declining city centres, old-industrial and harbour sites, and the working-class residential areas and undermined historical heritage sites of cities. The rise and mushrooming of such projects all over the world however brings about the questions related to their success level. This thesis aims to assess the success level of urban regeneration projects according to the measurable (qualitative and quantitative) features of integrated planning approaches. It seeks to develop a model to examine the success level of urban regeneration projects in physical, environmental, economic and social terms. Using case study as a research method, the research focuses on the on-going &amp / #8216 / Rehabilitation of the Fener and Balat Districts Programme&amp / #8217 / in the Istanbul Historical Peninsula, and tries to answer the question of how far this Programme can be successful in terms of regenerating the Fener-Balat Districts physically, environmentally, economically and socially.
37

Pest risk assessment for regulatory control of Bactrocera invadens (Diptera: Tephritidae) in the Musina area (Limpopo Province) / J.H. Venter.

Venter, Jan Hendrik January 2013 (has links)
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.
38

Pest risk assessment for regulatory control of Bactrocera invadens (Diptera: Tephritidae) in the Musina area (Limpopo Province) / J.H. Venter.

Venter, Jan Hendrik January 2013 (has links)
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.
39

An action research on the introduction of the use of authentic tasks in assessment to support a new integrated curriculum /

Tang, Mei-sin. January 1996 (has links)
Thesis (M. Ed.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 134-141).
40

An action research on the introduction of the use of authentic tasks in assessment to support a new integrated curriculum

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

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