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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.
61

Aide à la décision pour la planification des activités et des ressources humaines en hospitalisation à domicile / Decision support for planning the operations and the human resources in Home Health Care services

Redjem, Rabeh 08 July 2013 (has links)
L’hospitalisation hors les murs est une expression générique qui désigne toutes les formes de structures accueillant des patients pour une prise en charge longue et régulière nécessitant des soins complexes. Les structures hors les murs doivent assurer une prise en charge sure et d’une qualité au moins identique à celle fourni par l’hôpital, tout en contribuant à la diminution des coûts de la prise en charge. D’où la nécessité d’une gestion efficiente des activités des soignants et des ressources humaines. Dans ce travail de recherche, l’intérêt est porté à la problématique générale de gestion des activités de soins en Hospitalisation À Domicile (HAD). Il s’agit d’une problématique très complexe, car elle vise à résoudre simultanément des sous-problèmes réputés NP – difficiles. Dans cette thèse, nous étudions cette problématique au niveau opérationnel de la conception des tournées des soignants. La démarche adoptée pour ce travail de recherche se base sur trois étapes essentielles. Nous commençons par une étude sur le système de santé et les structures d’HAD en France, tout en mettant en claire les facteurs essentiels de leur fonctionnement. Cette étape sera clôturée par une étude du fonctionnement des systèmes d’HAD dans la région Rhône-Alpes, en se basant sur les retours du projet régional Organisation des Soins A Domicile (OSAD). La deuxième étape concerne les problématiques de gestion et la planification des activités de soins et des ressources humaines en HAD. Ce travail conduira à l’élaboration d’une classification des problématiques de la gestion des activités en HAD. En se basant sur la classification identifiée précédemment, nous définissons, les axes de complexité de ce problème : (i) le nombre d’activités de soins par soignant, (ii) la dépendance temporelle entre les activités des patients et (iii) la dimension environnementale. Ensuite, nous proposons un ensemble d’approches et d’outils pour la résolution de la problématique des tournées d’infirmiers en HAD, sous différentes contraintes liées à la réalisation des soins et en particulier aux contraintes de dépendances temporelles. Pour répondre à l’ensemble des contraintes et exigences de performance, nous développons une heuristique originale permettant une résolution en un temps compatible avec les contraintes de mise en oeuvre, pour des instances de grande taille / Home care services, is a generic term that gathers different kind of care: provider, agency, and organization. In France, the most important part of the in-home care is performed by HAD (Hospitalization At Home). The HAD concept is defined by decree. The HAD has to provide only complex care in the patient’s home for 24 motives. HAD are hospitals and have to ensure continuity of care for their patients. Our researches focus on the operation management for home care services. This problem is complex; it needs to solve sub-problems known to be NP - hard. In this work, this problem is studied at the operational level in design of tours of caregivers. The approach followed is based on three essential stages. Firstly, we study the health system and the home care structures in France. At the end of this step, we summarize the outcome obtained of the regional project Organization of Home Care Service (Organisation des Soins A Domicile : OSAD) on the home care structures in the Rhône-Alpes region (France). The second step gathers scientific literature about home care management, particularly about problems of management and planning of activities and human resources in the home care structures. This work leads to design a classification in order to management activities issues in home care structures. Based on this classification, we define three complexity axes of the operation management in home care problem, i.e. (i) the rate of the number of care activities per caregiver, (ii) dependency level between the patients’ activities and (iii) the environmental level. In the third stage, we suggest a set of mathematical approaches and tools for solving the problem of caregivers’ tours. Two MIPL model are developed, the first is based on a Traveling Salesman Problem (TSP) with coordination between the caregivers and the second on RCPSP (Ressources Constrained Project Scheduling Problem). Because the both previous models are time consuming, we suggest an original heuristic to solve the TSP coordinated problem, to resolve the care management activities in home care services
62

Tunnel Seismic Prediction in Stockholm Bypass / Tunnel Seismic Prediction i Förbifart Stockholm

Wessén, Matilda, Österberg, Janita January 2021 (has links)
Tunnel Seismic Prediction (TSP) is a geophysical investigation method used to predict the rock conditions ahead of the tunnel face. The method has been used in different types of rock and rock conditions. The Swedish Transport Administration, Trafikverket, has used the investigation method in multiple locations in the large infrastructure project E4 The Stockholm Bypass. The method is however rather new to Swedish rock conditions, and there is therefore a need to evaluate the method to assess its strengths and weaknesses. In this thesis, the TSP method is compared to other investigation methods used in the Stockholm Bypass project at the location Sätra-Kungshatt where the tunnels cross underneath Lake Mälaren. The investigation methods include geological mapping and Measurement While Drilling (MWD). The TSP results are also compared to the engineering geological prognosis. An evaluation of how the seismic primary and secondary waves, Vp and Vs, correlates to rock quality was carried out, and a linear regression analysis was performed to determine if the wave velocities found using the TSP method correlate with the Q value retrieved through the geological mapping. It was found that the TSP method is capable of detecting weaker zones of rock mass, however no correlation between the wave velocities and the Q value used to describe the quality of the rock mass was found. When comparing the TSP results to the MWD results, it was found that the methods could be used as complements to each other as the different methods sometimes detected weakness zones where the other method did not. As the geology in this location of Stockholm Bypass overall was found to be complex with rather poor rock mass quality, it could be concluded that the TSP method might be better suited for less complex geology where the contrast in rock quality is greater. / Tunnel Seismic Prediction (TSP) är en geofysisk undersökningsmetod för att tillhandhålla en prognos av berget framför tunnelstuffen. Metoden har använts i olika typer av berg och bergförhållanden. I Sverige har metoden använts av Trafikverket vid flertalet tillfällen i infrastrukturprojektet E4 Förbifart Stockholm. Metoden är dock relativt ny för de svenska bergförhållandena, vilket gör att det finns ett behov av att utvärdera metodens styrkor och svagheter i dessa förhållanden. I detta masterprojekt har resultaten som tillhandahållits från TSP-metoden jämförts med resultat från andra undersökningsmetoder som använts vid vattenpassagen vid Sätra-Kungshatt där tunneln korsar under Mälaren. Dessa undersökningsmetoder inkluderar geologisk kartering och Measurement While Drilling (MWD). TSP-resultaten har även jämförts med den ingenjörsgeologiska prognosen för området. Vikt har lagts på hur den seismiska primärvågen, Vp, och sekundärvågen, Vs, förhåller sig till den karterade bergkvaliteten. En regressionsanalys har även utförts för att avgöra om resultaten från TSP-metoden korrelerar med resultaten från den geologiska karteringen. Jämförelsen mellan de olika undersökningsmetoderna visade på att TSP kan påvisa svaghetszoner i bergmassan. Dock kunde ingen korrelation mellan våghastigheterna och Q värdet påvisas. Jämförelsen mellan TSP och MWD visade att de båda metoderna generellt visade liknande resultat. Dock kunde vissa avvikelser mellan resultaten från metoderna hittas, vilket göra att metoderna skulle kunna användas som komplement till varandra. Detta då de olika metoderna ibland kunde identifiera svaghetszoner som den andra metoden inte kunde identifiera. De svåra geologiska förhållandena på platsen kan ha bidragit till att TSP-resultaten över lag är relativt svårtolkade, vilket gör att TSP-metoden möjligtvis är bättre lämpad för mindre komplexa bergförhållanden där kontrasten mellan bra och dålig bergkvalitet är tydligare.
63

Avaliação espacial e sazonal das concentrações de partículas totais em suspensão e elementos metálicos associados no ar do município de Ribeirão Preto / SP / Spatial and seasonal evaluation of concentrations of total suspended particles and associated metallic elements in the air of Ribeirão Preto city

Machado, Gabriel Pinheiro 29 March 2018 (has links)
A atmosfera é a camada de gases que envolve a Terra e apresenta componentes essenciais aos seres vivos, porém também apresenta poluentes capazes de tornar o ar nocivo à saúde humana e ao meio ambiente. A poluição atmosférica é responsável por cerca de 3,6 milhões de mortes prematuras por ano no mundo todo e para contornar esse problema, autoridades criam padrões de qualidade do ar como limites de concentração de poluentes máximos tolerados em um período de tempo, com base em evidências científicas sobre o seu risco de exposição. Dentre os poluentes atmosféricos, destaca-se o material particulado, que é a união e a mistura de partículas sólidas e líquidas suspensas no ar. As Partículas Totais em Suspensão (PTS) são uma fração desta classe de poluentes, que apresenta um diâmetro inferior a 100 µm. Entre os PTS se destacam as partículas inaláveis grossas (2,5 µm <= 10 µm) e finas (<= 2,5 µm) por sua capacidade de atingir vias respiratórias inferiores, como traqueia e alvéolos, respectivamente. O material particulado pode conter também substâncias tóxicas como metais pesados, que podem gerar uma série de doenças carcinogênicas e efeitos adversos ao organismo. O presente estudo avaliou as concentrações de PTS e metais associados em três regiões distintas da cidade de Ribeirão Preto (Centro, Campus e Aeroporto), nas estações seca e chuvosa. Foi utilizado um amostrador de grande volume como método de coletas de PTS, por meio de filtros de fibra de vidro. Os metais foram dosados por Espectrometria de Plasma Indutivamente Acoplado (ICPMS). Os valores das concentrações de PTS foram comparados com os padrões nacionais e estaduais de qualidade do ar, enquanto as concentrações de metais foram comparadas às diretrizes de instituições internacionais. Não foram encontradas diferenças significativas (p > 0,05) nas concentrações de PTS e metais entre os pontos de coletas, exceto para Cu, Cr e Zn, que apresentaram maiores concentrações na região central (Cu e Cr) e no aeroporto (Zn). Foi verificada variação sazonal para PTS e os seguintes metais associados: As, Be, Cu, Mn, Ni, Pb, Sn e V, sendo as maiores concentrações observadas no período seco. Os valores das concentrações de PTS não ultrapassaram os padrões de qualidade do ar no estado de São Paulo, porém na estação seca, duas amostras coletadas no Centro e uma no Aeroporto ultrapassaram o limite secundário determinado pela legislação nacional e dessa forma podem causar uma diminuição no bem-estar pela população que reside próxima a esses locais. Concluiu-se que apesar do ar da cidade de Ribeirão Preto ter se apresentado dentro dos limites da legislação para as concentrações de PTS, estas podem causar problemas à saúde da população. Dessa maneira, medidas preventivas devem ser tomadas por meio de políticas públicas para melhorar o controle da qualidade do ar local e reduzir os riscos à saúde da população / The atmosphere is the layer of gases that surrounds the Earth and presents components essential to living beings, but also presents pollutants that can make the air harmful to human health and the environment. Air pollution is responsible for 3,6 million premature deaths per year worldwide and to circumvent this problem, authorities create air quality standards as limits of concentration of maximum tolerated pollutants over a period of time, based scientific evidence of their risk of exposure. Among the atmospheric pollutants, the particulate matter, which is the union and the mixture of solid and liquid particles suspended in the air, stands out. Total Suspended Particles (TSP) are a fraction of this class of pollutants, which has a diameter of less than 100 ?m. Among the TSP, inhaled particles are coarse (2.5 ?m <= 10 ?m) and fine (<= 2.5 ?m) due to their capacity to reach lower respiratory tract, such as trachea and alveoli, respectively. Particulate matter may also contain toxic substances such as heavy metals, which can lead to a number of carcinogenic diseases and adverse effects on the body. The present study evaluated the concentrations of TSP and associated metals in three distinct regions of Ribeirão Preto city (Central City, Campus and Airport), in the dry and rainy seasons. A large volume sampler was used for TSP sampling, using glass fiber filters. Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) dosed the metals. The TSP concentration values were compared to the national and state air quality standards, while the concentrations of metals were compared to the guidelines of international institutions. There were no significant differences (p <0.05) in the concentrations of TSP and metals between the sampling sites, except for Cu, Cr and Zn, which presented higher concentrations in the Central City (Cu and Cr) and at the Airport (Zn) . Seasonal variation was observed for TSP and the following associated metals: As, Be, Cu, Mn, Ni, Pb, Sn and V, being the highest concentrations observed in the dry period. TSP concentration values did not exceed air quality standards in the state of São Paulo, but in the dry season, two samples collected at the Central City and one at the Airport exceeded the secondary limit determined by national legislation and may represent a decrease in the welfare on these locations. It was concluded that although the air of Ribeirão Preto was occurred within the limits of the legislation for PTS concentrations, these can cause problems to the health of the population. In this way, preventive measures must be taken through public policies to improve local air quality control and reduce the health risks of the population.
64

Path Planning Algorithms for Multiple Heterogeneous Vehicles

Oberlin, Paul V. 16 January 2010 (has links)
Unmanned aerial vehicles (UAVs) are becoming increasingly popular for surveillance in civil and military applications. Vehicles built for this purpose vary in their sensing capabilities, speed and maneuverability. It is therefore natural to assume that a team of UAVs given the mission of visiting a set of targets would include vehicles with differing capabilities. This paper addresses the problem of assigning each vehicle a sequence of targets to visit such that the mission is completed with the least "cost" possible given that the team of vehicles is heterogeneous. In order to simplify the problem the capabilities of each vehicle are modeled as cost to travel from one target to another. In other words, if a vehicle is particularly suited to visit a certain target, the cost for that vehicle to visit that target is low compared to the other vehicles in the team. After applying this simplification, the problem can be posed as an instance of the combinatorial problem called the Heterogeneous Travelling Salesman Problem (HTSP). This paper presents a transformation of a Heterogenous, Multiple Depot, Multiple Traveling Salesman Problem (HMDMTSP) into a single, Asymmetric, Traveling Salesman Problem (ATSP). As a result, algorithms available for the single salesman problem can be used to solve the HMDMTSP. To show the effectiveness of the transformation, the well known Lin-Kernighan-Helsgaun heuristic was applied to the transformed ATSP. Computational results show that good quality solutions can be obtained for the HMDMTSP relatively fast. Additional complications to the sequencing problem come in the form of precedence constraints which prescribe a partial order in which nodes must be visited. In this context the sequencing problem was studied seperately using the Linear Program (LP) relaxation of a Mixed Integer Linear Program (MILP) formulation of the combinatorial problem known as the "Precedence Constrained Asymmetric Travelling Salesman Problem" (PCATSP).
65

Evaluation of PM10 and Total Suspended Particulate Sampler Performance Through Wind Tunnel Testing

Thelen, Mary Katherine 2010 August 1900 (has links)
Particulate matter (PM) concentrations in ambient air can be monitored by gravimetric sampling near a source using Federal Reference Method (FRM) samplers. PM is regulated by size, with PM10, which is comprised of particles with aerodynamic equivalent diameters less than or equal to 10 μm, being the main focus of this research. FRM PM10 samplers exhibit sampling errors when sampling dusts with mass median diameters (MMDs) that are larger than the 10 μm sampler cutpoint. For industries to be regulated equitably, these sampler errors must be quantified and understood. This research evaluates the performance of FRM PM10 and low volume total suspended particulate (TSP) samplers under the controlled conditions of a wind tunnel. The performance evaluation was conducted by observing the sampler cutpoints, slopes, and measured concentrations. These measured values were compared to values obtained using a collocated isokinetic reference sampler. The results of this research indicate that PM10 samplers do not operate as intended under all conditions. The cutpoint of the PM10 inlets was significantly higher than the maximum FRM limit of 10.5 μm when sampling dust with MMDs larger than the cutpoint of the sampler. The slope values for the PM10 inlets were significantly higher than the maximum FRM limit of 1.6. MMDs and geometric standard deviations of PM collected by TSP samplers were significantly different than those of PM collected using the collocated isokinetic sampler. The concentrations measured by the TSP samplers were significantly higher than the collocated isokinetic sampler. The results of this research provide a better understanding of the performance of TSP and PM10 samplers operating under different conditions and shows that these samplers are not operating as intended. Because of this, industries may be suffering the consequences of inequitable regulation.
66

A Case Study: Improvement Of Component Placement Sequence Of A Turret Style Smt Machine

Cengel, Savas Mehmet 01 January 2007 (has links) (PDF)
This study aims to improve component placement sequencing of a number of PCBs produced on a turret style SMT machine. After modeling the problem and having found that an optimal solution to the real PCB problem is hard to be achieved because of the concurrent behavior of the machine and the PCB design parameters, two heuristics are developed by oversimplifying the problem down to TSP. Performance of the heuristics and the lower bounds is evaluated by comparing the results with the optimal solution for two sets of randomly generated PCBs. The heuristic solutions are also compared with the lower bounds and the current implementation for the real PCBs. It is found out that the heuristics improve the current efficiency figures of the company.
67

A Genetic Algorithm For Tsp With Backhauls Based On Conventional Heuristics

Onder, Ilter 01 September 2007 (has links) (PDF)
A genetic algorithm using conventional heuristics as operators is considered in this study for the traveling salesman problem with backhauls (TSPB). Properties of a crossover operator (Nearest Neighbor Crossover, NNX) based on the nearest neighbor heuristic and the idea of using more than two parents are investigated in a series of experiments. Different parent selection and replacement strategies and generation of multiple children are tried as well. Conventional improvement heuristics are also used as mutation operators. It has been observed that 2-edge exchange and node insertion heuristics work well with NNX using only two parents. The best settings among different alternatives experimented are applied on traveling salesman problem with backhauls (TSPB). TSPB is a problem in which there are two groups of customers. The aim is to minimize the distance traveled visiting all the cities, where the second group can be visited only after all cities in the first group are already visited. The approach we propose shows very good performance on randomly generated TSPB instances.
68

The Biobjective Traveling Salesman Problem With Profit

Simsek, Omur 01 September 2004 (has links) (PDF)
The traveling salesman problem (TSP) is defined as: given a finite number of cities along with the cost of travel between each pair of them, find the cheapest way of visiting all the cities only once and returning to your starting city. Some variants of TSP are proposed to visit cities depending on the profit gained when the visit occurs. In literature, these kind of problems are named TSP with profit. In TSP with profit, there are two conflicting objectives, one to collect profit and the other to decrease traveling cost. In literature, TSP with profit are addressed as single objective, either two objectives are combined linearly or one objective is constrained with a specified bound. In this study, a multiobjective approach is developed by combining &amp / #949 / -constrained method and heuristics from the literature in order to find the efficient frontier for the TSP with profit. The performance of approach is tested on the problems studied in the literature. Also an interactive software is developed based on the multiobjective approach.
69

A Genetic Algorithm For The Biobjective Traveling Salesman Problem With Profits

Karademir, Serdar 01 July 2008 (has links) (PDF)
In Traveling Salesman Problem (TSP) with profits, a profit is associated with each city and the requirement to visit all cities is removed. The purpose is to simultaneously minimize cost (excluding as many cities as possible) and maximize profit (including as many cities as possible). Although the reduced single-objective case of the problem has been well-studied, the true biobjective problem has been studied only by a few researchers. In this paper we study the true biobjective problem using the Multiobjective Genetic Algorithm NSGA II and the Lin-Kernighan Heuristic. We propose several improvements for NSGA II in solving the problem. Based on these improvements, we provide computational results of the approximated Pareto-optimal front for a set of practically large size TSP instances. Finally, we provide a framework and its computational results for a post-optimality analysis to guide the decision maker, using the data mining software Clementine.
70

Engineering approaches to address erros in measured and predicted particulate matter concentrations

Wanjura, John David 16 August 2006 (has links)
Some of the air pollution regulations in the United States are based on an application of the National Ambient Air Quality Standards at the property line. Agricultural operations such as cotton gins, feed mills, and cattle feed yards may be inappropriately regulated by such regulations if the current methods of measuring and predicting the concentrations of regulated pollutants are used. The regulated particulate matter pollutants are those with aerodynamic equivalent diameters less than or equal to a nominal 10 and 2.5 micrometers (PM10 and PM2.5) respectively. The current Federal Reference Method PM10 and PM2.5 samplers exhibit oversampling errors when sampling dusts with particle size distributions similar to those of agricultural sources. These errors are due to the interaction of the performance characteristics of the sampler with the particle size distribution of the dust being sampled. The results of this work demonstrate the development of a new sampler that may be used to accurately sample total suspended particulate (TSP) concentrations. The particle size distribution of TSP samples can be obtained and used to more accurately determine PM10 and PM2.5 concentrations. The results of this work indicate that accurate measures of TSP can be taken on a low volume basis. This work also shows that the low volume samplers provide advantages in maintaining more consistent sampling flow rates, and more robust measurements of TSP concentrations in high dust concentrations. The EPA approved dispersion model most commonly used to estimate concentrations downwind from a stationary source is the Industrial Source Complex Short Term version 3 (ISCST3). ISCST3 is known to over-predict downwind concentrations from low level point sources. The results of this research show that the magnitude of these errors could be as much as 250%. A new approach to correcting these errors using the power law with P values as a function of stability class and downwind distance is demonstrated. Correcting the results of ISCST3 using this new approach results in an average estimated concentration reduction factor of 2.3.

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