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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.
131

The Impact of Change on System of Systems Performance with an Application to Small and Medium Multihospital Systems

Tayeb, Karima 01 August 2011 (has links)
An entity that functions as a system of systems (SoS) is composed of multiple systems that individually provide various functions which collectively provide a holistic functional capability. It is complex in design and function and tends to become even more complex over time as it evolves and responds to both internal and external changes. These changes might be in the composition or in the interoperability among its system members. Since interoperability affects how well the members work as one system, managing it is critical to the performance of the SoS over its lifespan. In support of this goal, this dissertation, through research and analysis of small-medium hospital systems, develops a descriptive approach to assist management in determining the impact that changes in membership and interoperability of member systems might have on SoS performance. A modeling approach was used to assess SoS performance before and after changes. This model is part of an analysis framework called Tri-Ex that can be used by managers to evaluate proposed system changes. The procedures and techniques used are recommended for any future investigations into applicability for SoS performance in different domains; designing system structure with future capabilities in mind; and operational assessment during development.
132

Svenska reglementens relevans för afghanistaninsatsen : En jämförelse avseende skydd av lokalbefolkningen

Vrenngård, Thomas January 2010 (has links)
<p>Föreliggande arbete undersöker metodmässig interoperabilitet genom att jämföra de kommande svenska reglementena <em>Reglemente för Markoperationer</em> och <em>Markstridsreglemente 6 – Bataljon</em> och deras överensstämmelse med den doktrin som nyttjas av International Security Assistance Force (ISAF) i Afghanistan. Undersökningen syftar till att lämna ett bidrag till den svenska reglementsutvecklingen.</p><p>Arbetet visar att det finns en överensstämmelse avseende grundbudskapet att lokalbefolkningen behöver skyddas och att man måste förstå deras situation. Det föreligger en låg grad av överensstämmelse avseende metoder för att skydda befolkningen.</p><p>Författaren lämnar tre rekommendationer:1. Omarbeta beskrivningen av stabiliserande metoder2. Inkludera begreppet ”Clear-Hold-Build”3. Inarbeta verktyg för att analysera den mänskliga terrängen</p>
133

Svenska reglementens relevans för afghanistaninsatsen : En jämförelse avseende skydd av lokalbefolkningen

Vrenngård, Thomas January 2010 (has links)
Föreliggande arbete undersöker metodmässig interoperabilitet genom att jämföra de kommande svenska reglementena Reglemente för Markoperationer och Markstridsreglemente 6 – Bataljon och deras överensstämmelse med den doktrin som nyttjas av International Security Assistance Force (ISAF) i Afghanistan. Undersökningen syftar till att lämna ett bidrag till den svenska reglementsutvecklingen. Arbetet visar att det finns en överensstämmelse avseende grundbudskapet att lokalbefolkningen behöver skyddas och att man måste förstå deras situation. Det föreligger en låg grad av överensstämmelse avseende metoder för att skydda befolkningen. Författaren lämnar tre rekommendationer:1. Omarbeta beskrivningen av stabiliserande metoder2. Inkludera begreppet ”Clear-Hold-Build”3. Inarbeta verktyg för att analysera den mänskliga terrängen
134

Computer Modelling of Neuronal Interactions in the Striatum

Hjorth, Johannes January 2009 (has links)
Large parts of the cortex and the thalamus project into the striatum,which serves as the input stage of the basal ganglia. Information isintegrated in the striatal neural network and then passed on, via themedium spiny (MS) projection neurons, to the output stages of thebasal ganglia. In addition to the MS neurons there are also severaltypes of interneurons in the striatum, such as the fast spiking (FS)interneurons. I focused my research on the FS neurons, which formstrong inhibitory synapses onto the MS neurons. These striatal FSneurons are sparsely connected by electrical synapses (gap junctions),which are commonly presumed to synchronise their activity.Computational modelling with the GENESIS simulator was used toinvestigate the effect of gap junctions on a network of synapticallydriven striatal FS neurons. The simulations predicted a reduction infiring frequency dependent on the correlation between synaptic inputsto the neighbouring neurons, but only a slight synchronisation. Thegap junction effects on modelled FS neurons showing sub-thresholdoscillations and stuttering behaviour confirm these results andfurther indicate that hyperpolarising inputs might regulate the onsetof stuttering.The interactions between MS and FS neurons were investigated byincluding a computer model of the MS neuron. The hypothesis was thatdistal GABAergic input would lower the amplitude of back propagatingaction potentials, thereby reducing the calcium influx in thedendrites. The model verified this and further predicted that proximalGABAergic input controls spike timing, but not the amplitude ofdendritic calcium influx after initiation.Connecting models of neurons written in different simulators intonetworks raised technical problems which were resolved by integratingthe simulators within the MUSIC framework. This thesis discusses theissues encountered by using this implementation and gives instructionsfor modifying MOOSE scripts to use MUSIC and provides guidelines forachieving compatibility between MUSIC and other simulators.This work sheds light on the interactions between striatal FS and MSneurons. The quantitative results presented could be used to developa large scale striatal network model in the future, which would beapplicable to both the healthy and pathological striatum. / QC 20100720
135

From Interoperability to Harmonization in Metadata Standardization : Designing an Evolvable Framework for Metadata Harmonization

Nilsson, Mikael January 2010 (has links)
Metadata is an increasingly central tool in the current web environment, enabling large-scale, distributed management of resources. Recent years has seen a growth in interaction between previously relatively isolated metadata communities, driven by a need for cross-domain collaboration and exchange. However, metadata standards have not been able to meet the needs of interoperability between independent standardization communities. For this reason the notion of metadata harmonization, defined as interoperability of combinations of metadata specifications, has risen as a core issue for the future of web-based metadata. This thesis presents a solution-oriented analysis of current issues in metadata harmonization. A set of widely used metadata specifications in the domains of learning technology, libraries and the general web environment have been chosen as targets for the analysis, with a special focus on Dublin Core, IEEE LOM and RDF. Through active participation in several metadata standardization communities, a body of knowledge of harmonization issues has been developed. The thesis presents an analytical framework of concepts and principles for understanding the issues arising when interfacing multiple standardization communities. The analytical framework focuses on a set of important patterns in metadata specifications and their respective contribution to harmonization issues: Metadata syntaxes as a tool for metadata exchange. Syntaxes are shown to be of secondary importance in harmonization. Metadata semantics as a cornerstone for interoperability. This thesis argues that the incongruences in the interpretation of metadata descriptions play a significant role in harmonization. Abstract models for metadata as a tool for designing metadata standards. It is shown how such models are pivotal in the understanding of harmonization problems. Vocabularies as carriers of meaning in metadata. The thesis shows how portable vocabularies can carry semantics from one standard to another, enabling harmonization. Application profiles as a method for combining metadata standards. While application profiles have been put forward as a powerful tool for interoperability, the thesis concludes that they have only a marginal role to play in harmonization. The analytical framework is used to analyze and compare seven metadata specifications, and a concrete set of harmonization issues is presented. These issues are used as a basis for a metadata harmonization framework where a multitude of metadata specifications with different characteristics can coexist. The thesis concludes that the Resource Description Framework (RDF) is the only existing specification that has the right characteristics to serve as a practical basis for such a harmonization framework, and therefore must be taken into account when designing metadata specifications. Based on the harmonization framework, a best practice for metadata standardization development is developed, and a roadmap for harmonization improvements of the analyzed standards is presented. / QC 20101117
136

Standardizing our perinatal language to facilitate data sharing

Massey, Kiran Angelina 05 1900 (has links)
Our ultimate goal as obstetric and neonatal care providers is to improve care for mothers and their babies. Continuous quality improvement (CQI) involves iterative cycles of practice change and audit of ongoing clinical care identifying practices that are associated with good outcomes. A vital prerequisite to this evidence based medicine is data collection. In Canada, much of the country is covered by separate fragmented silos known as regional reproductive care databases or perinatal health programs. A more centralized system which includes collaborative efforts is required. Moving in this direction would serve many purposes: efficiency, economy in the setting of limited resources and shrinking budgets and lastly, interaction among data collection agencies. This interaction may facilitate translation and transfer of knowledge to care-givers and patients. There are however many barriers towards such collaborative efforts including privacy, ownership and the standardization of both digital technologies and semantics. After thoroughly examining the current existing perinatal data collection among Perinatal Health Programs (PHPs), and the Canadian Perinatal Network (CPN) database, it was evident that there is little standardization of definitions. This serves as one of the most important barriers towards data sharing. To communicate effectively and share data, researchers and clinicians alike must construct a common perinatal language. Communicative tools and programs such as SNOMED CT® offer a potential solution, but still require much work due to their infancy. A standardized perinatal language would not only lay the definitional foundation in women’s health and obstetrics but also serve as a major contribution towards a universal electronic health record.
137

Investigating regional electronic information exchange as a measure of healthcare system integration: Making the invisible visible

McMurray, Diana Josephine Begley January 2013 (has links)
BACKGROUND Integrated healthcare systems are believed to be enabled by the electronic exchange of clinical information. Canada and other national health systems are making substantial investments in information technology, in order to liberate and share clinical information between providers, improve the quality and safety of care, and reduce costs, yet we currently have no way of measuring these information flows, nor of understanding whether they contribute to the integration of care delivery. METHODS A literature review and consensus development process (nominal group) were used to provide guidance on system integration measures which are enabled by electronic information exchange. In order to conceptualize the components of electronic information exchange, establish a reference vocabulary for terminology, and guide the development of a questionnaire to gather field data, a formal ontology was developed. Validation of a sub-group of the survey data quality was achieved using the ontology and an unrelated database, demonstrating how ontologies may be used to adapt performance measurement methodologies to systems where constraints such as time-compression, lack of resources or access to needed information are prevalent. RESULTS The survey tool gathered cross-sectoral data from a regional health system which populated a summary measure of inter-provider electronic health information exchange (the eHIE), and measured perceptions of system integration from a single health region. The eHIE indicated that 7 -12% of clinical information that could be shared, was being shared electronically in the health region. ANOVA confirmed a significant correlation between the amount of information being exchanged electronically in this system and respondent perceptions of system integration suggesting that the eHIE may be used as a leading indicator for healthcare system integration. CONCLUSIONS It is possible to conceptualize and quantify inter-provider electronic health information exchange. As complex adaptive systems, healthcare systems are dynamic and open to correction; the use of a leading or proximal indicator such as the eHIE may inform effective policy-making and resource allocation in our pursuit of the goal of seamlessly integrated care.
138

GMPLS-OBS interoperability and routing acalability in internet

Mendoça Pedroso, Pedro Miguel 16 December 2011 (has links)
The popularization of Internet has turned the telecom world upside down over the last two decades. Network operators, vendors and service providers are being challenged to adapt themselves to Internet requirements in a way to properly serve the huge number of demanding users (residential and business). The Internet (data-oriented network) is supported by an IP packet-switched architecture on top of a circuit-switched, optical-based architecture (voice-oriented network), which results in a complex and rather costly infrastructure to the transport of IP traffic (the dominant traffic nowadays). In such a way, a simple and IP-adapted network architecture is desired. From the transport network perspective, both Generalized Multi-Protocol Label Switching (GMPLS) and Optical Burst Switching (OBS) technologies are part of the set of solutions to progress towards an IP-over-WDM architecture, providing intelligence in the control and management of resources (i.e. GMPLS) as well as a good network resource access and usage (i.e. OBS). The GMPLS framework is the key enabler to orchestrate a unified optical network control and thus reduce network operational expenses (OPEX), while increasing operator's revenues. Simultaneously, the OBS technology is one of the well positioned switching technologies to realize the envisioned IP-over-WDM network architecture, leveraging on the statistical multiplexing of data plane resources to enable sub-wavelength in optical networks. Despite of the GMPLS principle of unified control, little effort has been put on extending it to incorporate the OBS technology and many open questions still remain. From the IP network perspective, the Internet is facing scalability issues as enormous quantities of service instances and devices must be managed. Nowadays, it is believed that the current Internet features and mechanisms cannot cope with the size and dynamics of the Future Internet. Compact Routing is one of the main breakthrough paradigms on the design of a routing system scalable with the Future Internet requirements. It intends to address the fundamental limits of current stretch-1 shortest-path routing in terms of RT scalability (aiming at sub-linear growth). Although "static" compact routing works fine, scaling logarithmically on the number of nodes even in scale-free graphs such as Internet, it does not handle dynamic graphs. Moreover, as multimedia content/services proliferate, the multicast is again under the spotlight as bandwidth efficiency and low RT sizes are desired. However, it makes the problem even worse as more routing entries should be maintained. In a nutshell, the main objective of this thesis in to contribute with fully detailed solutions dealing both with i) GMPLS-OBS control interoperability (Part I), fostering unified control over multiple switching domains and reduce redundancy in IP transport. The proposed solution overcomes every interoperability technology-specific issue as well as it offers (absolute) QoS guarantees overcoming OBS performance issues by making use of the GMPLS traffic-engineering (TE) features. Keys extensions to the GMPLS protocol standards are equally approached; and ii) new compact routing scheme for multicast scenarios, in order to overcome the Future Internet inter-domain routing system scalability problem (Part II). In such a way, the first known name-independent (i.e. topology unaware) compact multicast routing algorithm is proposed. On the other hand, the AnyTraffic Labeled concept is also introduced saving on forwarding entries by sharing a single forwarding entry to unicast and multicast traffic type. Exhaustive simulation campaigns are run in both cases in order to assess the reliability and feasible of the proposals.
139

Análisis de la evolución de la interoperabilidad y de la seguridad ferroviaria en Europa en el periodo 1991-2011 y propuestas de mejora

Ribes Ardanuy, Josep Maria 03 October 2012 (has links)
The object of this thesis is to analyze the evolution of railway interoperability and safety in Europe in the period 1991-2011. This pretends to assess what has been the legislative process at EU level in the last 20 years. This analysis looks for to determine whether it has been established the strong enough bases to achieve fully interoperable Trans-European Railway Network in a reasonable time, with uniform security features. The second aspect is to determine those points that should be corrected and improved, or simply addressed, to accelerate the integration process. A common feature of the rail networks in the European countries is their strong national focus in regard to Railway traffic rules and technical standards. This leads to specific products often developed and implemented by the national industry. This has raised a strong dependence of the rail networks on the local suppliers. Furthermore in most cases this carry out an incompatibility of these networks with the networks of neighbouring countries. To illustrate this situation it is only necessary to remember the different gauges in national networks (1,668 mm in the Iberian Peninsula, 1,520 in Russia, Finland, Baltic republics, 1,435 mm in the other European countries) to which must be added the numerous narrow gauges regional and urban networks. Another good example is the different supply voltages: 1,500 V dc, 3,000 V dc, 25 kV 50 Hz, 15 kV 16 2/3 Hz, which should add the 625 V dc, 750 V dc, 1,200 V cc, used in trams and regional rail systems. In the field of railway signalling, more than six different and incompatible systems exit. As we show in this document there are hundreds of other parameters that are different from one network to another: the height of the overhead line, the height of the platforms, the gauges an so on and so forth. The lack of interoperability, affects decisively to the creation of a European single market in rail transport for both: goods and passengers, which prevents private (or public) rail undertakings to give trans-national services and create a single market. The thesis focuses on the study of the directives relate to the interoperability and railway safety, and the technical specifications for interoperability (TSI). It leaves for future analysis the detailed studies European standards being developed for the technical harmonization of each subsystem parts. According to the author when the concept of interoperability was lunched in 1996, probably it was thought that the technical harmonization would be much easier. However, when it was analyzed in depth it was found a large number of discrepancies between the technical characteristics of each network raised. These parameters such as width and height of the pantographs, the stresses of the overhead contact wires, the length of the neutral zones, the height of platforms, the different kinematic and dynamic gauges and a long list of different parameters, made it impossible, in practice, the movement of trains across borders in a generalized manner in a short term. Finally it was recognized the fact that, for achieving real harmonized lines, it would be necessary to invest a huge amount of money not justify by the cost-benefit analyzes. The Thesis concludes that is necessary to put in force more strong Technical Specifications of Interoperability that leave less degree of freedom to the Member states: determining a single objective parameter value, trying to reduce the permanent specific cases and solving and reducing the list of open points. / El propósito de esta tesis es analizar el desarrollo de la interoperabilidad y seguridad ferroviaria en Europa en el periodo comprendido entre 1991-2011. La intención es evaluar cuál ha sido el proceso legislativo a nivel de la UE durante los últimos 20 años. Este análisis tratará de determinar si ha sido establecido desde una base suficientemente sólida para obtener una Red Ferroviaria Trans-Europea dentro de un periodo razonable, con uniformidad de instalaciones de seguridad. El segundo aspecto sería determinar aquellos puntos que deben ser corregidos o mejorados, o sencillamente re-examinados para acelerar el proceso de integración. Un aspecto común a las redes ferroviarias de los países europeos es su fuerte énfasis nacional en lo que respecta a normas de circulación ferroviaria y reglamentación técnica. Esta realidad conduce a la creación e implementación de productos específicos por parte de la industrial nacional. Esto ha llevado a una fuerte dependencia de las redes ferroviarias de suministradores locales. Asimismo, en la mayoría de los casos, esto lleva a la incompatibilidad de estas redes con las redes de países vecinos. Para ilustrar esta situación, solamente es necesario recordar los distintos anchos de vía en redes nacionales (1.668 mm en la península ibérica, 1.520 en Rusia, Finlandia y las repúblicas del Báltico, 1.435 mm en otros países europeos) al que habría que añadir las numerosas redes de vías de ancho estrecho regionales y urbanas. Otro buen ejemplo serían los distintos suministros de tensión: 1.500 V dc, 3.000 V dc, 25 kV 50 Hz, 15 kV 2/3 Hz, al que habría que añadir las de 625 V dc, 750 V dc, 1.200 V cc, utilizados en tranvías y redes de trenes regionales. En el ámbito de la señalización ferroviaria, existen más de seis sistemas distintos e incompatibles. Tal y como demostramos en este documento, hay cientos de parámetros distintos que difieren de una red a otra: la altura de la línea suspendida, la altura de andenes, los anchos, etc, etc. La falta de interoperabilidad afecta decisivamente a la creación de un mercado común europeo de transporte ferroviario para tanto mercancías como pasajeros, lo cual impide que empresas privadas (o públicas) ferroviarias puedan ofrecer servicios transnacionales y crear un solo mercado. Esta tesis se enfoca en el estudio de la reglamentación relacionada con la interoperabilidad y seguridad ferroviaria, y las especificaciones técnicas para la interoperabilidad (TSI). Deja para análisis futuros el estudio detallado de los estándares europeos bajo desarrollo para la armonización técnica de cada parte de subsistema. Según el autor, cuando el concepto de la interoperabilidad fue lanzada en 1996, probablemente se pensara que la armonización técnica sería mucho más sencilla. Sin embargo, al analizarlo en detalle se descubrió que aparecían un amplio número de discrepancias entras las características de cada red. Estos parámetros, como el ancho y alto de los pantógrafos, las tensiones de los hilos de contacto suspendidos, la longitud de zonas neutras, el alto de andenes, las diferentes propiedades cinemáticas y el ancho dinámico y una amplia lista de distintos parámetros hacían imposible en la práctica la circulación de trenes más allá de sus fronteras de forma generalizada a corto plazo. Por fin se reconoció el hecho de que para conseguir líneas verdaderamente armonizadas sería necesario invertir una enorme cantidad de dinero que no era justificable en los análisis de coste-beneficio. La tesis concluye que es necesario poner en vigencia especificaciones técnicas de interoperabilidad más fuertes que dejen menos libertad a los países miembros: determinar un solo valor de parámetro objetivo, y tratar de reducir los casos específicos permanentes y resolver y reducir el número de puntos abiertos.
140

Simulation Software as a Service and Service-Oriented Simulation Experiment

Guo, Song 28 July 2012 (has links)
Simulation software is being increasingly used in various domains for system analysis and/or behavior prediction. Traditionally, researchers and field experts need to have access to the computers that host the simulation software to do simulation experiments. With recent advances in cloud computing and Software as a Service (SaaS), a new paradigm is emerging where simulation software is used as services that are composed with others and dynamically influence each other for service-oriented simulation experiment on the Internet. The new service-oriented paradigm brings new research challenges in composing multiple simulation services in a meaningful and correct way for simulation experiments. To systematically support simulation software as a service (SimSaaS) and service-oriented simulation experiment, we propose a layered framework that includes five layers: an infrastructure layer, a simulation execution engine layer, a simulation service layer, a simulation experiment layer and finally a graphical user interface layer. Within this layered framework, we provide a specification for both simulation experiment and the involved individual simulation services. Such a formal specification is useful in order to support systematic compositions of simulation services as well as automatic deployment of composed services for carrying out simulation experiments. Built on this specification, we identify the issue of mismatch of time granularity and event granularity in composing simulation services at the pragmatic level, and develop four types of granularity handling agents to be associated with the couplings between services. The ultimate goal is to achieve standard and automated approaches for simulation service composition in the emerging service-oriented computing environment. Finally, to achieve more efficient service-oriented simulation, we develop a profile-based partitioning method that exploits a system’s dynamic behavior and uses it as a profile to guide the spatial partitioning for more efficient parallel simulation. We develop the work in this dissertation within the application context of wildfire spread simulation, and demonstrate the effectiveness of our work based on this application.

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