Spelling suggestions: "subject:"slab"" "subject:"slag""
71 |
Probability of SLA Violation for Semi-Markov AvailabilityGupta, Vivek 27 April 2009 (has links)
No description available.
|
72 |
Sustainable Livelihoods Approaches - Can they transform development?Mdee (nee Toner), Anna L. 12 1900 (has links)
yes / This paper critically examines the sustainable livelihoods approach (SLA) in the context of broader development debates, using a literature review as a tool to explore the origins, concepts and uses of the `approach¿. Whilst the concept of sustainable livelihoods is valuable in advancing our understanding the complexity and embedded nature of people¿s lives, sustainable livelihoods frameworks and principles are too simplistic to offer many answers. This paper argues that the idea of net sustainable livelihoods has much to offer the current discourse on rights and governance but that this is in danger of being diluted by its conceptualisation as a new `approach¿ to managing development interventions.
|
73 |
The Effects on Self-Regulation and Productive English Proficiency of the Application of Mental Contrasting and Implementation Intention (WOOP) in ESL Writing ClassesChan, Ka Yue 22 June 2023 (has links) (PDF)
The present study looked at the effects of a self-regulatory goal setting framework (WOOP) implemented in writing classes that were developed by Oettingen (2018) using Mental Contrasting and Implementation Intentions (MCII). The study examined English learners' development on self-reported self-regulation and proficiency levels in an Intensive English Program (IEP) in the United States over the course of two 14-week semesters. A total of 238 English Language Learners participated in the study and took the Short Self-Regulation Questionnaire (SSRQ) where the scores were analyzed to determine development over time. The analysis showed no statistically significant differences. However, experimental group participants' self-reported self-regulation tended to increase over time, even if only slightly. The same 238 participants also took a Level Acquisition Test (LAT) to assess their productive proficiency levels. The scores were also compared to a control group to determine if their proficiency was affected when the framework was implemented in the class. Based on the proficiency results, there were statistically significant differences in the development by experimental and control groups that were compared over time. In summary, WOOP, the self-regulatory framework that used MCII, may not have led to statistically significant differences in self-regulation, but the majority of the experimental group participants tended to improve in self-regulation, suggesting WOOP may be beneficial to help ESL learners improve their self-regulation. This research suggests the potential and value of further research with MCII in ESL contexts, specifically with longitudinal implementation of the framework, clarifications and instructions to better assist teachers and students, and further consideration of qualitative data looking at interviews, comments, personal reactions.
|
74 |
HyQoZ - Optimisation de requêtes hybrides basée sur des contrats SLA / HyQoZ – SLA-aware hybrid query optimizationLopez-Enriquez, Carlos-Manuel 23 October 2014 (has links)
On constate aujourd’hui une explosion de la quantité de données largement distribuées et produites par différents dispositifs (e.g. capteurs, dispositifs informatiques, réseaux, processus d’analyse) à travers de services dits de données. Dans ce contexte, il s’agit d’évaluer des requêtes dites hybrides car ils intègrent des aspects de requêtes classiques, mobiles et continues fournies par des services de données, statiques ou mobiles, en mode push ou pull. L’objectif de ma thèse est de proposer une approche pour l’optimisation de ces requêtes hybrides basée sur des préférences multicritère (i.e. SLA – Service Level Agreement). Le principe consiste à combiner les services de données et calcule pour construire un évaluateur de requêtes adapté au SLA requis par l’utilisateur, tout en considérant les conditions de QoS des services et du réseau. / Today we are witnesses of the explosion of data producer massively by largely distributed of data produced by different devices (e.g. sensors, personal computers, laptops, networks) by means of data services. In this context, It is about evaluate queries named hybrid because they entails aspects related with classic queries, mobile and continuous provided by static or nomad data services in mode push or pull. The objective of my thesis is to propose an approach to optimize hybrid queries based in multi-criteria preferences (i.e. SLA – Service Level Agreement). The principle is to combine data services to construct a query evaluator adapted to the preferences expressed in the SLA whereas the state of services and network is considered as QoS measures.
|
75 |
Qualité de service et calcul de chemins dans les réseaux inter-domaine et multicouches / Quality of service and path computation in inter-domain and multi-layer networksLamali, Mohamed Lamine 26 September 2014 (has links)
La Qualité de Service (Quality of Service - QoS) est une garantie de paramètres réseau (bande passante élevée, délai court, etc.). Dans un réseaux inter-domaine, elle peut être assurée par des contrats entre domaines appelés Service Level Agreements (SLA). Dans cette thèse, nous nous intéressons d’abord à l’étape de négociation de SLA : la sélection des SLA proposés par un domaine. Nous proposons des méthodes exactes et approchées permettant aux domaines de proposer les SLA qui maximisent leurs revenus. Nous étudions également l'impact de la réputation des domaines sur cette négociation. Au niveau de l’instanciation des SLA, nous nous intéressons au calcul de chemins qui prennent en compte les encapsulations de protocoles (afin de pallier l’hétérogénéité technologique des domaines). En utilisant des outils de théorie des langages, nous proposons la première solution polynomiale au calcul de chemins dans un tel contexte / Quality of Service (QoS) is a guarantee of network parameters (high bandwidth, short delay, etc.). In an inter-domaine network, it can be provided by contracts between domains, called Service Level Agreements (SLAs). In this thesis, we first focus on the SLA negotiation step, i.e., the selection of SLAs proposed by a domain. We provide exact and approximate methods that allow the domains to propose the SLAs that maximize their revenues. We also study the impact of the domain reputation on the negotiation process. Regarding the SLA instantiation step, we focus on path computation processes that take into account the encapsulation of protocols (in order to overcome the domain technological heterogeneity). Using tools from Language Theory, we provide the first polynomial solution to the path computation problem in this context.
|
76 |
Managing Service Dependencies in Service CompositionsWinkler, Matthias 21 June 2010 (has links)
In the Internet of Services (IoS) providers and consumers of services engage in business interactions on service marketplaces. Provisioning and consumption of services are regulated by service level agreements (SLA), which are negotiated between providers and consumers. Trading composite services requires the providers to manage the SLAs that are negotiated with the providers of atomic services and the consumers of the composition. The management of SLAs involves the negotiation and renegotiation of SLAs as well as their monitoring during service provisioning. The complexity of this task arises due to the fact that dependencies exist between the different services in a composition. Dependencies between services occur because the complex task of a composition is distributed between atomic services. Thus, the successful provisioning of the composite service depends on its atomic building blocks. At the same time, atomic services depend on other atomic services, e.g. because of data or resource requirements, or time relationships. These dependencies need to be considered for the management of composite service SLAs.
This thesis aims at developing a management approach for dependencies between services in service compositions to support SLA management. Information about service dependencies is not explicitly available. Instead it is implicitly contained in the workflow description of a composite service, the negotiated SLAs of the composite service, and as application domain knowledge of experts, which makes the handling of this information more complex. Thus, the dependency management approach needs to capture this dependency information in an explicit way. The dependency information is then used to support SLA management in three ways. First of all dependency information is used during SLA negotiation the to ensure that the different SLAs enable the successful collaboration of the services to achieve the composite service goal. Secondly, during SLA renegotiation dependency information is used to determine which effects the renegotiation has on other SLAs. Finally, dependency information is used during SLA monitoring to determine the effects of detected violations on other services.
Based on a literature study and two use cases from the logistics and healthcare domains different types of dependencies were analyzed and classified. The results from this analysis were used as a basis for the development of an approach to analyze and represent dependency information according to the different dependency properties. Furthermore, a lifecycle and architecture for managing dependency information was developed. In an iterative approach the different artifacts were implemented, tested based on two use cases, and refined according to the test results Finally, the prototype was evaluated with regard to detailed test cases and performance measurements were executed.
The resulting dependency management approach has four main contributions. Firstly, it represents a holistic approach for managing service dependencies with regard to composite SLA management. It extends existing work by supporting the handling of dependencies between atomic services as well as atomic and composite services at design time and during service provisioning. Secondly, a semi-automatic approach to capturing dependency information is provided. It helps to achieve a higher degree of automation as compared to other approaches. Thirdly, a metamodel for representing dependency information for SLA management is shown. Dependency information is kept separately from SLA information to achieve a better separation of concerns. This facilitates the utilization of the dependency management functionality with different SLA management approaches. Fourthly, a dependency management architecture is presented. The design of the architecture ensures that the components can be integrated with different SLA management approaches. The test case based evaluation of the dependency management approach showed its feasibility and correct functioning in two different application domains. Furthermore, the performance evaluation showed that the automated dependency management tasks are executed within the range of milliseconds for both use cases.
The dependency management approach is suited to support the different SLA management tasks. It supports the work of composite service providers by facilitating the SLA management of complex service compositions.
|
77 |
Allocation optimale multicontraintes des workflows aux ressources d’un environnement Cloud Computing / Multi-constrained optimal allocation of workflows to Cloud Computing resourcesYassa, Sonia 10 July 2014 (has links)
Le Cloud Computing est de plus en plus reconnu comme une nouvelle façon d'utiliser, à la demande, les services de calcul, de stockage et de réseau d'une manière transparente et efficace. Dans cette thèse, nous abordons le problème d'ordonnancement de workflows sur les infrastructures distribuées hétérogènes du Cloud Computing. Les approches d'ordonnancement de workflows existantes dans le Cloud se concentrent principalement sur l'optimisation biobjectif du makespan et du coût. Dans cette thèse, nous proposons des algorithmes d'ordonnancement de workflows basés sur des métaheuristiques. Nos algorithmes sont capables de gérer plus de deux métriques de QoS (Quality of Service), notamment, le makespan, le coût, la fiabilité, la disponibilité et l'énergie dans le cas de ressources physiques. En outre, ils traitent plusieurs contraintes selon les exigences spécifiées dans le SLA (Service Level Agreement). Nos algorithmes ont été évalués par simulation en utilisant (1) comme applications: des workflows synthétiques et des workflows scientifiques issues du monde réel ayant des structures différentes; (2) et comme ressources Cloud: les caractéristiques des services de Amazon EC2. Les résultats obtenus montrent l'efficacité de nos algorithmes pour le traitement de plusieurs QoS. Nos algorithmes génèrent une ou plusieurs solutions dont certaines surpassent la solution de l'heuristique HEFT sur toutes les QoS considérées, y compris le makespan pour lequel HEFT est censé donner de bons résultats. / Cloud Computing is increasingly recognized as a new way to use on-demand, computing, storage and network services in a transparent and efficient way. In this thesis, we address the problem of workflows scheduling on distributed heterogeneous infrastructure of Cloud Computing. The existing workflows scheduling approaches mainly focus on the bi-objective optimization of the makespan and the cost. In this thesis, we propose news workflows scheduling algorithms based on metaheuristics. Our algorithms are able to handle more than two QoS (Quality of Service) metrics, namely, makespan, cost, reliability, availability and energy in the case of physical resources. In addition, they address several constraints according to the specified requirements in the SLA (Service Level Agreement). Our algorithms have been evaluated by simulations. We used (1) synthetic workflows and real world scientific workflows having different structures, for our applications; and (2) the features of Amazon EC2 services for our Cloud. The obtained results show the effectiveness of our algorithms when dealing multiple QoS metrics. Our algorithms produce one or more solutions which some of them outperform the solution produced by HEFT heuristic over all the QoS considered, including the makespan for which HEFT is supposed to give good results.
|
78 |
Garantia de qualidade dos provedores de serviços de aplicativos (ASP), empregando os acordos dos níveis de serviços (SLA): uma pesquisa exploratória / Quality guarantee of Application Service Providers (ASP), employing Service Level Agreements (SLA): an exploratory researchFigueiredo, Rejane Maria da Costa 19 December 2002 (has links)
A economia globalizada e os avanços tecnológicos propiciaram um novo modelo de Outsourcing de Tecnologia de Informação (TI): os provedores de serviços de aplicativos (ASP - Application Service Providers). As discussões a respeito de ASP intensificaram-se nos três últimos anos, com a proposta de comercialização do software como um serviço. Quanto maior a interdependência da área de TI com as metas de negócios das organizações, maior a ênfase dada à satisfação das expectativas do cliente quanto aos serviços prestados pelos provedores. No mercado, têm-se adotado os acordos dos níveis de serviços (SLA - Service Level Agreements) como mecanismo de controle das atividades de outsourcing. Porém, essa adoção é nova e imatura, e a literatura é escassa. Tanto os provedores quanto os cliente sentem a necessidade por estruturas de implantação semelhantes às de SLA. Essa carência é ressaltada no caso dos modelos ASP. Propondo-se a contribuir com a compressão do modelo ASP e de SLA para ASP, apresenta-se uma pesquisa exploratória das características desse modelo com SLA, de modelos de qualidade de serviços de outsourcing e finalmente de considerações que devem ser feitas para garantir a qualidade dos serviços ASP, empregando-se os SLA. / The global economy and technological advances propitiated a new model of Information Technology (IT) Outsourcing: the Application Service Providers - ASP. Discussions regarding ASP became more frequent in the last three years because of the new approach of selling software as a service. As the interdependency between the IT area and the business goals of organizations becomes greater, the emphasis on fulfilling the client\'s expectations regarding service rendered by providers becomes stronger. In the market, Service Level Agreements - SLA have been adopted as control mechanisms of outsourcing activities. However, this adoption is new and immature, and the literature on the matter is scarce. Providers and clients feel the need for implementation structures similar to SLA\'s. In lhe case of ASP models, this necessity is emphasized mainly due to the lack of conceptual information on the ASP model. In order to better comprehend lhe ASP and the SLA models for ASP, I am presenting an exploratory research about the characteristics of the new approach with SLA models, outsourcing models of service quality and considerations, which must be carried out to ensure quality of ASP services employing SLA.
|
79 |
Frameworks de governan?a de TIC aplicados em SLA de VoIP sobre WLAN / ICT governance frameworks applied on SLA for VoIP over WLANMartinati, Rafael Rodrigo 19 June 2009 (has links)
Made available in DSpace on 2016-04-04T18:31:24Z (GMT). No. of bitstreams: 1
Rafael Rodrigo Martinati.pdf: 892328 bytes, checksum: bb06e7a9c52ea61c8c7545d477f6b0f3 (MD5)
Previous issue date: 2009-06-19 / The objective of this paper is to analyze the development of Service Level Agreement to Voice over Internet Protocol over WIFI services in compliance with COBIT, ITIL and ISO / IEC 20.000-1:20005 and ISO 38.500 frameworks, specially using perceived quality of speech as a SLA requirement . The models MOS, PESQ and E MODEL published by the ITU for evaluation of quality of speech analyzed was identified the hypothesis that the E MODEL provide compliance with the frameworks of ICT governance. It was emulated a Voice over Internet Protocol over WIFI scenario and measured is the variation of the R FACTOR, in different encoders and compared with the changes in jitter and rate of loss packets. We can conclude that E model has characteristics that make it able to be inserted into a Service Level Agreements for Voice over Internet Protocol over WIFI service. / Este trabalho discorre sobre acordos de n?vel de servi?os, ou Service Level Agreements (SLA) para servi?os Voice over Internet Protocol (VoIP) sobre redes Wireless Local Area Network (WLAN). Foram considerados como fundamentos os frameworks Control Objectives for Information and related Technologies (CobiT), Information Technology Infrastructure Library (ITIL) e as normas ISO/IEC 38.500 e ISO/IEC 20.000-1 e constatouse que a qualidade de fala percebida deve ser um requisito de um SLA para VoIP. Foram analisados os modelos de avalia??o de qualidade de fala Mean Opinion Score (MOS), Perceptual Evaluation of Speech Quality (PESQ) e Modelo E, publicados pela International Telecommunications Union (ITU) onde foi identificada a hip?tese de que o Modelo E esteja em conformidade com os frameworks de governan?a de Tecnologia da Informa??o e Comunica??o (TIC), por fornecer um indicador, o fator R, que pode ser considerado como um indicador de SLA. Para comprova??o desta hip?tese, foram analisados dados, obtidos em uma emula??o de um ambiente real de redes WLAN para medi??o da varia??o do fator R, utilizando-se de dispositivos codificadores (CODEC) e cen?rios diferentes. Constatou-se que o fator R apresentou a mesma tend?ncia de qualidade de fala nos diferentes dispositivos CODEC. Foram ent?o comparadas as varia??es de jitter e taxa de perda de pacotes nos mesmos cen?rios e codificadores para analisar se a varia??o destas m?tricas possui relacionamento com as medidas do fator R. Identificou-se ent?o que o fator R apresenta caracter?sticas que permitem que ele seja inserido em um SLA de um servi?o VoIP, viabilizando assim a requisitos de governan?a e gest?o de servi?os de TIC.
|
80 |
Estudo randomizado e duplo cego com uso de difosfato de cloroquina para a manuntenção de remissão da hepatite autoimune apos a suspensão da imunossupressão / A randomized double-blind study with chloroquine diphosphate for rmaintenance of remission of autoimmune hepatitis after immunosuppression withdrawalTerrabuio, Débora Raquel Benedita 24 April 2018 (has links)
INTRODUÇÃO: 50-86% dos pacientes recidivam a hepatite autoimune (HAI) após a suspensão do tratamento imunossupressor. A manutenção da imunossupressão em longo prazo diminui o risco de recidiva, entretanto é necessário ajuste da dose/suspensão do tratamento em 10-30%, em razão do maior risco de neoplasias e infecções. O difosfato de cloroquina (CQ) é droga imunomoduladora que foi utilizada anteriormente em monoterapia para manutenção da remissão da HAI com diminuição da recidiva quando comparada com controle histórico. O objetivo desse estudo foi investigar a eficácia e segurança do CQ na manutenção da remissão em estudo duplo cego e randomizado e avaliar se há um subgrupo com maior benefício ao seu uso. METODOLOGIA: 61 pacientes com diagnóstico provável ou definitivo de HAI em remissão histológica, 90,1% HAI tipo 1; 23% com reatividade do anti-SLA/LP, 56,6% com fibrose avançada (F3/4) à inclusão no estudo, mas com doença hepática compensada, foram randomizados de forma duplo cego e aleatória para receber CQ 250 mg/d ou placebo, durante 36 meses ou até recidiva da doença. No primeiro mês a droga foi utilizada em combinação com a imunossupressão que induziu remissão; com posterior desmame semanal da prednisona, suspensão imediata da azatioprina e manutenção do CQ/placebo até 36 meses. As curvas de sobrevida livre de recidiva foram estimadas pelo método de Kaplan-Meyer e comparadas pelo teste de Log-Rank; as razões de risco e seus respectivos intervalos de confiança foram estimados por regressão simples de Cox. Na regressão múltipla foram avaliadas co-variáveis clinicamente relevantes para recidiva. Para investigar o subgrupo com maior benefício, as interações entre a droga e reatividade de autoanticorpos e perfil de HLA foram analisadas por regressão múltipla de Cox. As variáveis categóricas foram comparadas pelo teste exato de Fisher e as quantitativas pelo teste-t ou teste de Mann-Whitney. Foi considerado estatisticamente significante um valor de p < 0,05. RESULTADOS: 31 pacientes receberam CQ e 30 placebo. Não houve diferenças entre os grupos em relação aos achados clínicos, laboratoriais, histológicos e perfil de HLA. A sobrevida livre de recidiva foi significativamente maior no grupo CQ quando comparada ao placebo (59,3% X 19,9%, p=0,039). Após a suspensão da medicação ao término do estudo, houve 41,6% de recidiva no grupo CQ e 0% no placebo. Na regressão simples de Cox, os fatores associados com recidiva da HAI foram uso placebo, reatividade do anticorpo anti-SLA/LP, perfil de HLA DR3 e DR8. Na regressão múltipla, o uso de placebo (razão de risco de 2,4[IC 95%:1,05- 5,5], p=0,039) e reatividade do anticorpo anti-SLA/LP (razão de risco= 5.4 [IC 95%:1,91-15,3], p=0,002) associaram-se a maior risco de recidiva. Não foi possível definir subgrupo de maior benefício com uso de CQ no que se refere à reatividade do anti-SLA/LP ou perfil de HLA, embora a recidiva tenha ocorrido em 100% dos pacientes anti-SLA/LP(+) no grupo placebo e 50% no grupo CQ. No grupo CQ, 54,8% apresentaram efeitos colaterais, com suspensão da droga em 19,3%. Os efeitos colaterais mais comuns foram prurido e hiperpigmentação cutânea. CONCLUSÕES: O CQ reduziu com segurança o risco de recidiva de HAI, mas não foi possível definir subgrupo com maior benefício com essa medicação / INTRODUCTION: 50-86% of patients relapse autoimmune hepatitis (AIH) after immunosuppressive treatment withdrawal, with a higher risk of progression to liver cirrhosis, death due to liver disease and liver transplantation. The maintenance of long-term immunosuppression decreases the risk of relapse, however, treatment dose adjustment and/or interruption is required in 10-30%, with increased risk of neoplasias and infections. Chloroquine diphosphate (CQ) is an immunomodulatory drug used previously in monotherapy to maintain AIH remission with a decrease risk in relapse rates when compared to a historical control. The aims of this study were to investigate the efficacy and safety of CQ in the maintenance of remission in a double-blind and randomized study, and to evaluate if there is a subgroup with a greater benefit of its use. METHODS: 61 patients with probable or definitive diagnosis of AIH in histological remission, 90.1% type 1; 23% with anti-SLA / LP seropositivity, 56.6% with advanced fibrosis [F3 / 4] at inclusion in the study and with compensated liver disease were randomized double-blindly to receive either CQ 250 mg/day or placebo for 36 months or until relapse. In the first month, the drug was used in combination with the immunosuppressive regimen that induced the remission; with subsequent weekly weaning of prednisone, immediate withdrawal of azathioprine and maintenance of CQ/placebo for up to 36 months. Recurrence-free survival curves were estimated by the Kaplan-Meyer method and compared by the Log-Rank test; the hazard ratios and their respective confidence intervals were estimated by simple Cox regression. Clinically relevant covariables for relapse were re-evaluated bymultiple Cox regression. To investigate the existence of a subgroup with a greater benefit, interactions between the drug and autoantibody reactivity and HLA profile were analyzed by the Cox multiple regression. Categorical variables were compared by Fisher\'s exact test and the quantitative by the t-test or Mann- Whitney test. A p value of < 0.05 was considered statistically significant. RESULTS: 31 patients received CQ and 30 placebo. There were no differences between the two groups in relation to clinical, laboratory, histological and HLA profiles. Relapse-free survival was significantly higher in the CQ group when compared to placebo (59.3% X 19.9%, p=0.039). After antimalarial withdrawal at the end of the study, there was 41.6% relapse in the CQ group and 0% in the placebo. In the Cox simple regression, factors associated with AIH relapse were placebo use, anti-SLA/LP seropositivity, and HLA DR3 and DR8 profiles. In multiple regression, placebo use (Hazard Ratio = 2.4 [95% CI: 1.05-5.5], p = 0.039) and anti-SLA/LP seropositivity (Hazard Ratio = 5.4 [95% CI: 1.91-15.3], p = 0.002) were associated with a higher risk of relapse. It was not possible to define a subgroup with a greater benefit of CQ with respect to anti-SLA/LP positivity or HLA profile, although all anti-SLA/LP(+) patients in placebo group relapsed, compared to 50% in CQ group. In the CQ group, 54.8% had side effects, but 19.3% had drug withdrawal. The most common side effects were pruritus and cutaneous hyperpigmentation. CONCLUSIONS: Chloroquine safely reduced the risk of relapse of AIH, but it was not possible to define a subgroup with greater benefit with medication use
|
Page generated in 0.0434 seconds