• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 35
  • 10
  • 4
  • 3
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 62
  • 62
  • 18
  • 16
  • 13
  • 10
  • 10
  • 9
  • 8
  • 8
  • 8
  • 8
  • 7
  • 6
  • 6
  • 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.
61

Analyse d’implantation d’initiatives d’amélioration continue de la qualité des soins aux personnes vivant avec le VIH en Haïti

Demes, Joseph Adrien Emmanuel 10 1900 (has links)
Cette thèse vise à mieux comprendre le processus d’implantation des initiatives d’amélioration de la qualité des soins en Haïti. Un programme national d’amélioration continue de la qualité, HEALTHQUAL-Haïti, a été choisi pour la réalisation d’une analyse d’implantation. Pour être systématique dans cette recherche évaluative, le modèle logique du programme d’amélioration continue de la qualité (PACQ) HEALTHQUAL-Haïti a été réalisé. Ce modèle a permis par la suite de poser les bonnes questions pour déterminer le degré de mise en œuvre de HEALTHQUAL-Haïti. Puis les facteurs qui ont facilité ou entravé la mise en œuvre du PACQ ont été analysés. Il s’agit d’une thèse par article. Trois (3) articles constituent le cœur de cette thèse : le premier présente le processus d’élaboration du modèle logique de HEALTHQUAL-Haïti ; le second apprécie le degré de mise en œuvre du programme HEALTHQUAL-Haïti ; le troisième présente les facteurs qui influencent le degré de mise en œuvre de HEALTHQUAL-Haïti. Ce dernier montre un cadre conceptuel avec différentes perspectives théoriques pour expliquer la mise en œuvre du programme HEALTHQUAL-Haïti tenant compte de la réalité empirique. Des facteurs externes et des facteurs internes influencent la mise en œuvre du programme HEALTHQUAL : les facteurs externes, particulièrement les caractéristiques des réseaux, la capacité de négociation, la capacité de mobilisation de ressources, la capacité de vaincre les résistances au changement, l’héritage politique, les normes institutionnelles, la situation socio-politique du pays et des facteurs internes comme le leadership partagé, l’appropriation du processus par les acteurs, le jeu de pouvoir, l’apprentissage organisationnel, la structure organisationnelle, le degré de motivation des prestataires, la culture des prestataires et la disponibilité des ressources. Un résultat fondamental, c’est que les modèles du changement, pris de façon isolée, n’expliquent que partiellement la mise en œuvre. Par ailleurs, c’est une configuration de facteurs tant externes qu’internes qui déterminent le degré de mise en œuvre à un moment donné. Sept (7) modèles du changement ont été retenus : le modèle politique, néo-institutionnel, psychologique, de l’apprentissage organisationnel, du développement organisationnel, le modèle structurel et le modèle rationnel. La culture organisationnelle interagit avec les variables des différents modèles du changement soit pour faciliter ou entraver la mise en œuvre du programme HEALTHQUAL. Ces différentes combinaisons de facteurs forment des archétypes, qui, à un moment donné, déterminent le degré d’implantation du programme HEALTHQUAL. / This thesis aims to better understand the process of implementing initiatives to improve the quality of care in Haiti. We have chosen a national continuous quality improvement program, HEALTHQUAL-Haïti, to conduct an implementation analysis using case studies. To be systematic in our evaluative research, we first produced the logic model of the Continuous Quality Improvement Program, HEALTHQUAL-Haiti. This model then allowed us to ask the right questions and select the right variables to analyze the degree of implementation of HEALTHQUAL-Haïti. We then looked at the factors that facilitated or hindered the implementation of the HEALTHQUAL-Haiti program. We have opted for a thesis by articles. Three (3) articles constitute this thesis: The first presents the process of developing the logical model of HEALTHQUAL-Haiti; the second assesses the degree of implementation of the HEALTHQUAL-Haiti program; the third presents the factors that influence the degree of implementation of HEALTHQUAL-Haiti. This last one describes a conceptual framework taking into account different theoretical perspectives to explain the implementation of the HEALTHQUAL-Haïti program. External and internal factors influence the implementation of the HEALTHQUAL program: external factors, particularly the characteristics of networks, negotiation capacity, capacity to mobilize resources, capacity to overcome resistance to change, political heritage, institutional norms, socio-political situation of the country, and internal factors such as shared leadership, ownership of the process by actors, power, organizational learning, organizational structure, level of motivation of providers, culture of providers, and availability of resources. What has been found is that models of change, taken in isolation, only partially explain implementation. Furthermore, we observed that it was a configuration of both external and internal factors that determined the degree of implementation at any given time. The different variables or concepts of seven models of change were considered: the political, neo-institutional, psychological, organizational learning, organizational development, structural and rational models. Organizational culture interacts with the variables of the different change models either to facilitate or hinder the implementation of the HEALTHQUAL program. These different combinations of factors form archetypes, which at any given time determine the implementation of the HEALTHQUAL program.
62

Oilfield produced water treatment with electrocoagulation

de Farias Lima, Flávia 27 September 2019 (has links)
Produced water is the largest waste product by volume in the oil industry and its treatment in onshore or offshore fields poses bigger and different challenges than what water engineers are used to encounter. Process to achieve reuse quality of this water is very expensive with many technical hurdles to overcome making the optimization of the treatment steps necessary. Electrocoagulation (EC) generates coagulants in-situ responsible for destabilizing oil droplets, suspended particles, and common pollutant in produced water. Furthermore, EC is a very efficient technology compared with traditional primary treatments used in the oil & gas industry and has several advantages such as: no hazardous chemical handling (which diminishes the risk of accident and logistic costs), high efficiency potential concerning boron removal, potential small footprint and less sludge generation. In this research, the treatment of produced water using EC was investigated in a practical manner for the oilfield to aim for a cleaner effluent for further processing and help to achieve a reuse quality. For this, an EC cell was designed using different parameters normally used in the literature to fit this scenario. After preliminary tests, the treatment time was set to 3 seconds. Response surface method (RSM) was employed to optimize the operating conditions for TOC removal on a broad quality of synthetic produced water while varying: salinity, initial oil concentration and initial pH. TOC was chosen to be the main response because of its importance in legislation and sensibility on the method. Furthermore, turbidity removal, change of pH value after EC in water with lack of buffer capacity, aluminum concentration and preliminary tests involving boron removal and influence of hydrogen carbonate were also studied. Real produced water was treated with EC to assess the optimum conditions obtained by the RSM showing the results were closely related. Finally, an estimation of volume required and operating cost for EC in the different types of produced water was made to assess how realistic it is for onshore and offshore applications.:ERKLÄRUNG DES PROMOVENDEN I ACKNOLEDGEMENT III ABSTRACT V TABLE OF CONTENT VII LIST OF FIGURES IX LIST OF TABLES X LIST OF EQUATIONS XII ABBREVIATIONS XIV 1. INTRODUCTION 1 2. PRODUCED WATER 6 2.1 Characterization of Oilfield Produced Water 6 2.2 Produced Water Management 10 2.2.1 Discharge and Regulations 10 2.2.2 Efforts on Reuse 11 2.2.3 Cost 14 3. PRODUCED WATER TREATMENT 17 3.1 Most Common Primary Treatment 17 3.1.1 Hydrocyclones 17 3.1.2 Flotation unit 18 3.2 Further Water Treatment Technologies 19 3.2.1 Membrane Process 19 3.2.1.1 Microfiltration 19 3.2.1.2 Ultrafiltration 21 3.2.1.3 Nanofiltration 23 3.2.1.4 Reverse Osmosis 24 3.2.1.5 Forward osmosis 24 3.2.2 Electrodialysis 25 3.2.3 Biological treatment 28 3.2.3.1 Aerobic and anaerobic process 28 3.2.3.2 Combining membrane and bio-reactor 29 3.2.4 Oxidative process 30 3.2.4.1 Oxidation process 30 3.2.4.2 Anodic oxidation 32 3.2.5 Thermal technology 34 3.2.5.1 Evaporation 34 3.2.5.2 Eutectic freeze crystallization 35 3.2.6 Adsorption and ion-exchange 36 3.3 Electrocoagulation 39 3.3.1 Colloidal Stability Theory 39 3.3.2 Theory of Electrocoagulation 40 3.3.3 Mechanism of Abatement of Impurities 44 3.3.4 Operational parameters and efficiency 49 4. MATERIALS AND METHODS 51 4.1 Analytical Techniques and Synthetic Solutions 51 4.1.1 Analytical Techniques 51 4.1.2 Synthetic Produced Water 51 4.2 Design of Experiment and Models 54 4.3 Experimental Protocol for EC 56 4 .4 Development of the new Electrocoagulation cell 57 4.5 Real Produced water 58 5. RESULTS AND DISCUSSION 59 5.1 Designing EC Cell Process 59 5.1.1 Computational Fluid Dynamics for EC manufacturing 59 5.2 Preliminary Experiments 61 5.2.1 TOC Removal and Residence Time Determination 61 5.2.2 Aluminum Concentration 64 5.3 Models Quality and Range of Validity 66 5.3.1 TOC Removal 66 5.3.2 Turbidity Removal 69 5.3.3 Final pH value 71 5.3.4 Ionic Strength and Interpolation for Different Salinities 73 5.3.5 Partial Conclusions 76 5.4 Evolution of the Final pH Value 78 5.5 Operation Region for Effective Treatment of Produced Water with EC 80 5.5.1 Produced Water with Low Salinity 80 Organic Compounds Removal 80 Turbidity Removal 83 5.5.2 Produced Water with Medium Salinity 84 Organic Compounds Removal 84 Turbidity Removal 86 5.5.3 Produced Water with High Salinity 87 Organic Compounds Removal 87 5.6 Influence of Hydrogen Carbonate 90 5.7 Real Produced water 91 5.8 Boron Removal 93 5.9 Estimation of the Size for EC in Full scale 94 5.10 Produced Water with Very Low Salinity and EC 95 5.11 Estimation of Operation Cost 96 6. CONCLUSION AND RECOMMENDATIONS 98 6.1 Conclusion 98 6.2 Recommendations for Future Work 101 Scale up on EC for upstream 101 Further processing and reuse 101 Online optimization for EC 101 Recommendations for any research related to upstream produced water 101 BIBLIOGRAPHY 102 APPENDIX A 117 APPENDIX B 120

Page generated in 0.0338 seconds