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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.
121

Santé et insécurité routière : influence de la consommation de médicaments (Étude CESIR-A) / Health-related factors and road safety : influence of medicine use (The CESIR-A study)

Orriols, Ludivine 27 September 2010 (has links)
La prise de conscience de l’implication des médicaments dans la genèse des accidents de la route date d’une vingtaine d’années. Les médicaments psycho-actifs peuvent altérer les capacités de conduite par leur action sur le système nerveux (par exemple, un effet sédatif le lendemain d’une prise d’hypnotique). D’autres médicaments sont susceptibles d’affecter les fonctions psychomotrices par leur action sur les fonctions physiologiques (tel que les hypoglycémies liées à un traitement antidiabétique). L’étude CESIR-A a été mise en place pour contribuer à la connaissance du lien épidémiologique entre médicaments et accidents de la route. L’étude utilise trois bases de données françaises : le Système National d’Information Inter-Régimes de l’Assurance Maladie (SNIIR-AM), les Procès Verbaux d’accidents (PV) et les Bulletins d’Analyse des Accidents Corporels de la circulation (BAAC). L’appariement de ces données a conduit à l’inclusion de 72,685 conducteurs impliqués dans un accident corporel sur la période juillet 2005-mai 2008. L’analyse a été réalisée grâce à deux méthodes: une analyse cas-témoin comparant les responsables aux non-responsables des accidents et une analyse dite en case-crossover. Les périodes d’exposition aux médicaments ont été estimées à partir des dates de délivrances de médicaments prescrits, puis remboursés par l’assurance maladie. L’étude des médicaments regroupés selon les quatre niveaux de risque sur la conduite définis par l’Agence Française de Sécurité Sanitaire des Produits de Santé (AFSSAPS) [du niveau 0 (pas de risque) au niveau 3 (risque élevé)], a montré que les utilisateurs de médicaments prescrits de niveau 2 et de niveau 3 ont un risque significativement plus élevé d’être responsables de leur accident (OR=1,31 [1,24-1,40] et OR=1,25 [1,12-1,40], respectivement). La fraction de risque attribuable à l’utilisation de ces médicaments était de 3,3% [2,7%-3,9%]. Le risque d’être responsable d’un accident était augmenté chez les utilisateurs de zolpidem (OR=1,28 [1,07-1,53]) mais pas chez les utilisateurs de zopiclone ou de benzodiazépines hypnotiques. Plus particulièrement, ce risque était augmenté chez les 139 conducteurs ayant eu plus d’un comprimé de zolpidem délivré par jour au cours des cinq mois précédant l’accident (OR=2,38 [1,61-3,52]). L’analyse case-crossover a mis en évidence un sur-risque d’accident de la route chez les utilisateurs de benzodiazépines hypnotiques seulement (OR=1,42 [1,09-1,85]). Les conducteurs exposés aux hypnotiques partagent les mêmes caractéristiques au regard du type d’accident, qui survenaient plus fréquemment sur autoroute. Dans notre base de données, 196 conducteurs ont été exposés à la buprénorphine et/ou à la méthadone, le jour de leur accident. Cette population spécifique était jeune, essentiellement masculine, avec d’importantes co-consommations, notamment d’alcool de médicaments de niveau 3. Les conducteurs exposés à la buprénorphine et/ou à la méthadone présentaient un risque accru d’être responsables de leur accident (OR= 2,19 [1,51-3,16]). Notre étude fournit des informations importantes sur la contribution des médicaments au risque d’accident de la route. D’après nos résultats, la classification de l’AFSSAPS semble appropriée concernant les médicaments de niveaux 2 et 3. Les sur-risques d’être responsable d’un accident chez les exposés au zolpidem ou aux traitements de substitution pourraient être liés, au moins en partie, au comportement à risque de ces conducteurs. L’amélioration du comportement des conducteurs représente un des défis pour la sécurité routière. L’objectif de la classification française et de la signalétique apposée sur les boîtes de médicaments est donc de fournir aux patients une information appropriée sur les effets des médicaments sur leur capacité de conduite. / In recent decades, attention has been increasingly focused on the impact of disabilities and medicinal drug use on road safety. Psychoactive medicines may impair driving abilities due to their action on the central nervous system (e.g. sedation in the morning following administration of a hypnotic), while other medicines may affect psychomotor functions by their action on physiological functions (e.g hypoglycaemic seizures related to diabetic treatment). The CESIR-A project was set up to improve the epidemiological knowledge on medicines and the risk of road traffic crashes. The study matched three French nationwide databases: the national healthcare insurance database, police reports, and the police national database of injurious crashes, leading to the inclusion of 72,685 drivers involved in an injurious road traffic crash from July 2005 to May 2008. Two methods were performed for data analysis: a case-control analysis in which cases where responsible drivers and controls non-responsible ones and a case-crossover analysis. Medicine exposures were estimated from prescription drug dispensations in the healthcare reimbursement database. The study of medicines grouped according to the four levels of driving impairment risk of the French classification system [from 0 (no risk) to 3 (high risk)], showed that users of level 2 and level 3 prescribed medicines were at higher risk of being responsible for the crash (OR=1.31 [1.24-1.40] and OR=1.25 [1.12-1.40], respectively). The fraction of road traffic crashes attributable to levels 2 and 3 medicines was 3.3% [2.7%-3.9%]. Zolpidem use was associated with an increased risk of being responsible for a road traffic crash (OR=1.28 [1.07-1.53]) whereas use of zopiclone and benzodiazepine hypnotics use was not. Responsibility risk was only increased in the 139 drivers with dispensing of more than one pill of zolpidem a day during the five months before the crash (OR=2.38 [1.61-3.52]). Case-crossover analysis showed an increased risk of crash for benzodiazepine hypnotic users only (OR=1.42 [1.09-1.85]). Hypnotic users shared similar crash characteristics, with crashes more likely to occur on highways. In our database, 196 drivers were exposed to buprenorphine and/or methadone on the day of crash. This specific population was young, essentially males, with important co-consumption of other substances, in particular alcohol and level 3 medicines. Injured drivers exposed to buprenorphine and/or methadone on the day of crash, had an increased risk of being responsible (OR=2.19 [1.51-3.16]). The case cross-over analysis did not demonstrate any association (OR=1.26 [0.93 - 1.70]). Our study provides evidence of the contribution of medicines to the risk of road traffic crashes. According to our results, the French risk classification seems relevant regarding medicines classified as levels 2 and 3 of risk for road traffic crashes. The observed increased risks of being responsible for a crash for zolpidem and substitution maintenance treatment users may be linked to risky behaviors. Improving driver behaviour is one of the challenges for road safety. Providing patients with proper information on the potential effect of medicines on their driving abilities is the main objective of drug and risk classifications such as the French one.
122

Facilitating customer retention in hotels in the Garden Route

Slabbert, Gabriel Johannes January 2010 (has links)
Over the past few decades, customer satisfaction, customer retention and policies and procedures to sustain the above mentioned, have earned great amount of lip service. The importance of satisfied customer percentage have been emphasized by theories even longer before the best advised companies have done so. It is only recently, on the eve of the Soccer World cup 2010 that the issue has been narrowed down to truly hard relationships and one hard question: “Will the guest visiting the hospitality establishment frequent the hotel?” Two vital financial catalysts were used as basis for customer retention. The first is that of old customer’s costs much less than acquisition of new ones and the profit generated from the retained customer must therefore handsomely exceed the harvest reaped from the new clientele. Retaining customers have become an intangible asset in the sense that their value demonstrates the return that is won by successful efforts to satisfy the customers so greatly that they and their custom literally and figuratively stays with you. South Africa has lured even the loneliest traveller to the scenic beauty that is cradled by the country and its surroundings. When taking the former into consideration, South African businesses have enjoyed an increased appreciation and application of Business Management and its accompanying principles. The hospitality industry should therefore embrace the business management principles with specific emphasis on Total Quality Management (TQM); providing managers with the capacity to think strategically about the organisation, its business position, how it can gain sustainable competitive advantage and how its business management strategy can be implemented and executed successfully. The latter forms the basis for ensuring the smooth running of operations and ultimately, ensuring guests have a wonderful experience at the particular establishment. There is a strong belief that lodging facilities in the Garden Route area has experienced low customer retention due to a lack of comprehensive implementation of Total Quality Management principles which impedes on the establishments to reach their optimum profit levels. It is for this reason that this thesis will argue the importance of the systematic client retention as a strategic mandate in today’s service markets. Commercial reality demand long and lasting relationships that are beneficial to both the hospitality related establishment and their customers. The hypothesis used is the application of Total Quality Management as a Business Management Strategy which will facilitate customer retention in hospitality related industries such as hotels situated in the Garden Route area. Research shows that service expectations of customers and potential customers have escalated. Hospitality businesses found that implementation of quality processes to be a vital competitive component. However, many hotels are still struggling to reach a real understanding of what is meant by TQM. The research data indicates that 93 percent of hotels in the Garden Route do not follow a TQM program although all the hotels were familiar with the concept. This might be the reason why most hotels neglect customer retention activities. The literature reviewed in chapter two considers the customer retention activities evaluated in the questionnaire as important to retain guests. Hotels in the Garden Route do not perform these activities to the extent of success. Hotel managers thus know what to do in order to retain guests but the problem is quite simple, they do not always implement the necessary strategies.
123

Vehicular Movement Patterns: A Sequential Patterns Data Mining Approach Towards Vehicular Route Prediction

Merah, Amar Farouk January 2012 (has links)
Behavioral patterns prediction in the context of Vehicular Ad hoc Networks (VANETs)has been receiving increasing attention due to enabling on-demand, intelligent traffic analysis and response to real-time traffic issues. One of these patterns, sequential patterns, are a type of behavioral patterns that describe the occurence of events in a timely-ordered fashion. In the context of VANETs, these events are defined as an ordered list of road segments traversed by vehicles during their trips from a starting point to their final intended destination, forming a vehicular path. Due to their predictable nature, undertaken vehicular paths can be exploited to extract the paths that are considered frequent. From the extracted frequent paths through data mining, the probability that a vehicular path will take a certain direction is obtained. However, in order to achieve this, samples of vehicular paths need to be initially collected over periods of time in order to be data-mined accordingly. In this thesis, a new set of formal definitions depicting vehicular paths as sequential patterns is described. Also, five novel communication schemes have been designed and implemented under a simulated environment to collect vehicular paths; such schemes are classified under two categories: Road Side Unit-Triggered (RSU-Triggered) and Vehicle-Triggered. After collection, extracted frequent paths are obtained through data mining, and the probability of these frequent paths is measured. In order to evaluate the e ciency and e ectiveness of the proposed schemes, extensive experimental analysis has been realized. From the results, two of the Vehicle-Triggered schemes, VTB-FP and VTRD-FP, have improved the vehicular path collection operation in terms of communication cost and latency over others. In terms of reliability, the Vehicle-Triggered schemes achieved a higher success rate than the RSU-Triggered scheme. Finally, frequent vehicular movement patterns have been effectively extracted from the collected vehicular paths according to a user-de ned threshold and the confidence of generated movement rules have been measured. From the analysis, it was clear that the user-de ned threshold needs to be set accordingly in order to not discard important vehicular movement patterns.
124

Towards High Quality Video Streaming over Urban Vehicular Networks Using a Location-aware Multipath Scheme

Wang, Renfei January 2012 (has links)
The transmitting of video content over Vehicular Ad Hoc Networks (VANETs) faces a great number of challenges caused by strict QoS (Quality of Service) requirements and highly dynamic network topology. In order to tackle these challenges, multipath forwarding schemes can be regarded as potential solutions. However, route coupling effect and the path length growth severely impair the performance of multipath schemes. In this thesis, the current research status about video streaming over VANETs as well as multipath transmissions are reviewed. With the demand to discover a more suitable solution, we propose the Location-Aware Multipath Video Streaming (LIAITHON+) protocol to address video streaming over urban VANETs. LIAITHON+ uses location information to discover relatively short paths with minimal route coupling effect. The performance results have shown it outperforms the underlying single path solution as well as the node-disjoint multipath solution. In addition, the impact of added redundancy on the multipath solution is investigated through LIAITHON+. According to the results, added redundancy has a different impact depending on the data rate.
125

Securing home and correspondent registrations in mobile IPv6 networks

Elshakankiry, Osama January 2011 (has links)
The Mobile IPv6 (MIPv6) protocol enables mobile nodes (MNs) to remain connected to other correspondent nodes (CNs) while roaming the IPv6 Internet. Home and correspondent registrations are essential parts of the MIPv6 protocol, whereby MNs register their care-of addresses (CoAs) with their home agents (HAs) and with their CNs, respectively. Security provision for home and correspondent registrations is a fundamental part of the MIPv6 protocol and has been an open research issue since the early stages of the protocol.This thesis examines state-of-the-art protocols for securing home and correspondent registrations in MIPv6 networks. The strengths and weaknesses of these protocols are discussed. The investigation of these protocols leads to the proposal of an enhanced home registration protocol and a family of correspondent registration protocols. The Enhanced Home Registration (EHR) protocol extends the basic home registration protocol defined in MIPv6 to support the location authentication of MNs to their HAs. The EHR is based on novel ideas of segmenting the IPv6 address space, using a symmetric CGA-based technique for generating CoAs, and applying concurrent CoAs reachability tests. As a result, EHR is able to reduce the likelihood of a malicious MN being successful in luring an HA to flood a third party with useless packets using MIPv6. In addition, EHR enables HAs to help in correspondent registrations by confirming MNs' CoAs to CNs. Simulation studies of EHR have shown that it only introduces a marginal increase in the registration delay, but a significant increase in the signalling overhead as a cost of supporting the location authentication of MNs.The thesis also proposes a family of correspondent registration protocols. These protocols rely on the assistance of home networks to confirm the MNs' ownership of the claimed HoAs and CoAs. The protocols consist of three phases: a creation phase, an update phase and a deletion phase. Informal and formal protocol analyses have confirmed the protocols' correctness and satisfaction of the required security properties. The protocols have been simulated extensively and the results show that they produce lower registration delay and a reduction in the signalling overhead during update and deletion phases. This is at the cost of a varying increase, depending on the protocol variant, in the registration delay and signalling overhead during the creation phase.
126

Innovation in distribution models at the base of the pyramid

Osborn, David Vincent 29 July 2012 (has links)
This study investigates how innovation in distribution models at the base of the pyramid overcomes the impact of institutional and infrastructural voids in the base of the pyramid (BOP) markets. The research was based on the qualitative assessment of successful companies currently operating in the healthcare, pharmaceuticals, fast moving consumables, beverages and financial, consulting and telecoms services space in BOP market in Africa and India. The research establishes that successful distribution is not possible without consideration of the needs and values of the lower income consumer in terms of understanding where they live, what they purchase and how they behave. Offerings to this market require the application of frugal engineering principles to address product specification, production cost and cost to access. Companies were then researched and the findings interpolated to create a distribution model that describes how companies’ route to market can take the form of either an active or passive mode of distribution. A case for best practise was then developed to describe the most innovative, successful approaches applied to the unique distribution problems in the BOP. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted
127

Införande av spårvägar i Örebro - Förslag till spårvägssträckning

Granath, Christian January 2012 (has links)
In Örebro, the car traffic share does not tend to decrease. The crowdedness on some of the bus routes is high at times. Investigations show that the residents of Örebro want a city centre whose street environment is more restrictive of car traffic and better for pedestrians, cyclists and public transport. To decrease the car traffic share a rapid, convenient, clear, effective and environmental friendly public transport with high frequency and strong capacity in a short, direct and logical network is needed. A modern tramway fulfils these criteria. At first, this report describes factors that are important to take into consideration when planning a tramway. Thereafter it comes with – from analysis of, among other things, the population density and travel pattern – suggestions for tramway routes through Örebro. Where more than one conceivable route alternative has been identified, comparisons have been made to illustrate their pros and cons. A big part of the work has been devoted to – after considering the physical condition of the street space – showing problems and possibilities, and coming up with proposals for the design. These are some of the conclusions made by the report (-gatan = the… street, -vägen = the… road):  A good starting point would be "tramwayfication" of the bus routes 1 to 4 and their wickerwork structure.  To avoid a big demand of complementing bus service the mean value of the tramways stop spacing in Örebro should not be bigger than 700 meters.  To give Vivalla an effective and attractive tramway it has to go straight through the area.  A route that goes via the Hedgatan/Kryptongatan intersection, between Baronbackarna and Vivalla centre, would be better than a route passing next to the Vivalla school. This is dependent, however, on new buildings being concentrated to the Vivalla/Lundby passage and the development of Vallby into no more than a low-density residential area.  A route along Malmgatan and Järnvägsgatan would be better than a route along Västra Nobelgatan and Östra Nobelgatan or Kilsgatan and Olaigatan.  Hedgatan between Långgatan and Trängkårsvägen, Västra Nobelgatan between Västerplan and Hertig Karls Allé (including the intersection Västra Nobelgatan/Hertig Karls Allé), Västra Nobelgatan between Lövstagatan and Gustavsgatan, Rudbecksgatan between Trädgårds-gatan and Mogatan, and Åstadalsvägen between Rundstigen and Barkvägen are places that can be tricky when it comes to the construction of a tramway and therefore require specific solutions.  For streets that could be subject to a future tramway, it would be more efficient and more cost effective to adjust the physical environment of the street – the sewage and drainage systems, for example – at the same time as any pre planned routine maintenance.  The housing areas along the current public transport passages should be made more concentrated; especially on those streets which could be subjected to a future tramway.  New constructions that could make the conditions worse for a future tramway should not be started. For example, the parking area in front of the main entrance to the hospital (USÖ) and the area immediately south of the roundabout next to the university should not be built on before plans for a future tramway have been finalised.
128

Development of a decision support tool for transit network design evaluation

Mzengereza, Isaac 06 March 2022 (has links)
Municipalities increasingly have less financial resources to spend on implementation of transport strategies and plans. This situation is putting pressure on transport professionals to minimize wasteful expenditure on projects that do not deliver high transport service improvements. As such, the need for efficient, pragmatic decision making on policy direction, infrastructure expenditure, or any transport interventions is becoming very critical. Thus, transport professionals are increasingly in need of tools to help them predict with increased accuracy the outcomes of their intended transport interventions. The City of Cape Town has a Bus Rapid Transport system called MyCiTi. Current MyCiTi operations are incurring losses. The service is kept running on the back of subsidies from the federal government. There is a need for rationalization of the system. However, with strained resources, the interventions on the system have to guarantee improvements. Overemphasis on the ability of MyCiTi BRT service to support transportation during the 2010 soccer world cup event heavily influenced the design of the network. As a result, network appraisal is one area that can be done on the system to identify areas of improvement. In this thesis, decision making support will be demonstrated using a network design appraisal process for the MyCiTi BRT system in Cape Town. The existing MyCiTi network will undergo network improvement using heuristic node insertion technique leading to multiple network scenarios in a modeling environment. Agent-Based demand mobility behavior simulation will be used on each of the network scenarios to come up with network performance indicators. These network performance indicators will be used in the multi-criteria decision analysis (MCDA) model to come up with a ranking of the network scenarios and help in deciding on the optimum network improvement intervention. Overall, findings of this research show the importance of weighting of the performance indicators. Where networks that score well in the performance indicator with the high weights also rank high. In conclusion, the study has demonstrated the importance of decision making support in interventions on complex systems like bus systems. Recommendations on the possible avenues of research stemming from this thesis have also been outlined.
129

A Novel Traffic Aware Data Routing Protocol in Vehicular Networks

Cui, Heqi 20 May 2022 (has links)
Recently, according to people's requirements for safe and congestion-free driving in the public transportation system, the intelligent transportation system (ITS) has been widely concerned. To achieve a safe and time-saving driving experience in ITS, various data sharing methods are proposed to provide traffic information for drivers to perceive their surrounding driving environment. However, the high dynamic characteristic of the vehicular network (VNET) results in a challenging environment for establishing stable communication among vehicles. To face this challenge, a Cellular network-assisted Reliable Traffic-Aware Routing protocol (CRTAR) is proposed in this thesis to provide support for vehicle’s data routing process in a heterogeneous vehicular-cellular network environment. In the method, city-wide traffic information, i.e., traffic density and data transmission density of the road segments, is introduced into vehicle's data routing process to assist the vehicle in selecting the optimal data transmission route to deliver data packets. To further improve the stability of inter-vehicle communication, the link lifetime between vehicles is also considered to select the next forwarder that can establish relatively robust communication. CRTAR takes advantage of the reliability and low-latency features of the communication technology in the cellular network and combines the cellular network with VNET to achieve real-time and reliable Vehicle-to-Infrastructure (V2I) communication. Meanwhile, it realizes the Vehicle-to-Vehicle (V2V) communication by the Dedicated Short Range Communication (DSRC) to mitigate the overload of backbone resources caused by using the cellular network. To be specific, in the method, vehicles can request city-wide traffic information via the cellular network from a cloud service that is connected to the remote data center located in the traffic management agency without latency. According to the real-time traffic information, the source vehicle can execute the data routing process with a global view of the system to calculate the data transmission route that has sufficient transmission resources to the target vehicle. The source vehicle then transmits data to the target via the vehicles in the calculated transmission route. During the forwarding process, vehicles prefer to forward the data packet to the next vehicle with a longer link lifetime. Furthermore, effective backup and recovery strategies are designed for route maintenance. The effectiveness of CRTAR is further verified by conducting simulation experiments.
130

A Mixed-Methods Study of Alternate-Route Teachers' Effect on Student Learning

Spearman, Cassandra Faye 01 January 2017 (has links)
Due to teacher shortages at the study site, teaching positions in the state that is the focus of this study are filled by alternate route (AR) teachers, who earned bachelor degrees in the fields that were not related to education and received teacher certification through alternative teacher education programs. Because there is limited information about the preparation and performance of AR teachers at the site of this study, the purpose of this sequential mixed methods project study was to explore AR teachers' preparation and their effect on student learning as measured by Northwest Evaluation Association's Measures of Academic Progress/Discovery Education Assessments. Guided by Mezirow's experiential learning theory and Dewey's educational philosophy, this project study investigated the relationship between the alternate route teachers' field experiences and years of experience, and teachers' effect on student learning. Data collection included a survey of 36 K-12 AR teachers selected through convenience sampling, document analysis of their student assessment scores, and 6 structured interviews with purposefully selected high performing AR teachers. Data were triangulated and cross-analyzed. Findings indicated that when AR teachers engage in field experiences prior to teaching, their students have higher levels of achievement as evidenced in their assessment scores. There was no correlation between AR teachers' years of teaching experience and their student assessment scores. Analysis of AR teachers' interview responses revealed a need for professional development, which was then created to address those needs. This study may contribute to social change by offering the targeted professional development of AR teachers and improving the design of AR preparation programs to better influence student learning.

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