Esta dissertação de mestrado propõe uma nova política de distibuição de requisições em cluster de web services, denominada Política Performance. Essa política provê uma distribuição transparente, flexível e dinâmica das requisições na plataforma em que é executada. Um estudo sistemático também é realizado para analisar a qualidade dos índices de carga empregados no contexto de web services e propõe um novo índice capaz de representar fielmente o desempenho dos web services e encapsular a complexidade estrutural da plataforma. Também é proposto em Módulo Gerenciador de Energia capaz de prover sustentabilidade à plataforma, reduzindo o consumo de energia elétrica sem prejudicar a alta confiabilidade na distribuição das requisições e com baixo impacto no tempo médio de resposta. Os estudos experimentais realizados neste trabalho mostraram que a Política Performance permitiu um melhor desempenho no atendimento das requisições realizadas à plataforma. EStes resultados referem-se a um desempenho superior a 70% no tempo médio de resposta, quando comparado ao desempenho demosntrado pela política padrão do Mod_cluster. O Módulo Gerenciador de Energia proporcionou uma redução de aproximadamente 30% no consumo de energia da plataforma mantendo a alta confiabilidade na distribuição das requisições / The Master\'s dissertation proposes a new for distribution of requests in cluster of web services, named policy Performance. This policy provides a transparent flexible and dynamic distribution of requests on the plataform. A systematic study is also conducted to example the quality of load indices used in the context of web services., and proposes a new index that accurately represent the performance of web services and encapsulate the complexity structural of the plataform. Also proposed is an Energy Manager Module capable of providing sustainability to the plataform, reducing power consumption without sacrificing high reliability in the distribution of request and low impact on the average response time. Our main results show that policy Performance has a better performance in handling requests sent to the plataform. Our results show a gain of performance higher than 70% in average responswetime when compared to the perormance demonstrated by the defaut policy Mod_cluster. The Power Manager Module reduced byapproximately 30% the energy consumption of the plataform even keeping the high reliability in the distribution of requests

Esta tese de doutorado analisa o impacto gerado pela virtualização assistida por hardware, de terceira geração, no desempenho de aplicações baseadas em SOA do tipo CPU-bound e memory-intensive, bem como nas operações de marshalling e unmarshalling de mensagens SOAP executadas nas bibliotecas dos servidores de aplicação. A partir dessa análise, concluiu-se que os recursos disponibilizados pela plataforma de hardware, principalmente no gerenciamento de memória, eliminam a sobrecarga gerada pela virtualização baseada em tradução binária, elevando os hypervisores bare-metal a um novo patamar, onde aplicações executadas sobre tais virtualizadores obtém, frequentemente, desempenho superior àquelas executadas em plataformas não virtualizadas. Assim, modificações nos modelos de desempenho de aplicações baseadas em SOA atualmente em uso são propostas, de acordo com a análise desenvolvida, para que reflitam os resultados obtidos de forma realista / This PhD thesis analyzes the impact caused by third generation hardware-assisted virtualization on the performance of CPU-bound and memory-intensive SOA-based applications, as well as the impact caused on the marshaling and unmarshalling operations of the SOAP messages executed on the libraries of the application servers. From this analysis is concluded that the resources provided by the hardware platform, mainly considering the memory management, eliminate the overload generated by virtualization based on binary translation, raising the bare-metal hypervisors to a new level, where applications running on these hypervisors reach better performance when compared to those applications running on platforms not virtualized. Thus, modifications on the performance models for SOAbased applications currently in use are proposed accordingly to the analysis developed, aiming at reflecting the results obtained in a realistic fashion

Service-oriented environments are central backbone of todays enterprise workflows. These workflow includes traditional process types like travel booking or order processing as well as data-intensive integration processes like operational business intelligence and data analytics. For the latter process types, current execution semantics and concepts do not scale very well in terms of performance and resource consumption. In this paper, we present a concept for data streaming in business processes that is inspired by the typical execution semantics in data management environments. Therefore, we present a conceptual process and execution model that leverages the idea of stream-based service invocation for a scalable and efficient process execution. In selected results of the evaluation we show, that it outperforms the execution model of current process engines.

Les aérosols atmosphériques (par exemple les matières particulaires ou PM) sont une source majeure d’incertitude dans les modèles climatiques. Plusieurs études ont démontré que des concentrations élevées de PM réduisent l’espérance de vie. Les aérosols organiques secondaires (Secondary Organic Aerosols en anglais, SOA) sont formés dans l’atmosphère à partir des précurseurs gazeux à travers les réactions chimiques et les SOA représentent des composants majeurs de la masse des PM à l’échelle mondiale. Afin de mieux comprendre les processus chimiques responsables de la formation des SOA, un modèle en 0-D est élaboré pour simuler dynamiquement l’évolution des espèces organiques dans une parcelle d’air qui subit une oxydation photochimique produisant des SOA. Le modèle incorpore des paramètres récemment publiés pour la formation des SOA à partir des composés organiques volatiles (VOCs), ainsi que des composés organiques semi-volatiles et des composés organiques à volatilité intermédiaire (SVOCs et IVOCs). Le modèle est restreint par plusieurs mesures de précurseurs, incluant des mesures récemment développées qui fournissent des contraintes grandement améliorées sur les concentrations des précurseurs, et les prédictions sont comparées par rapport aux mesures des SOA prises au cours de la campagne CalNex. Lorsque les effets des pertes sur les parois des chambres à smog sont considérés pour les rendements des VOCs, la quantité et la vitesse de la formation des SOA dans le modèle sont plus en accord avec les observations. Les résultats de cette étude indiquent que les SVOCs et les IVOCs primaires sont responsables de la majorité (70 à 86 %) de la masse de SOA modélisée, accentuant leur grande contribution en tant que précurseurs des SOA. Cependant, la masse de SOA simulée est sous-estimée à des temps courts d’oxydation lorsque comparée aux données sur le terrain, mais à des temps plus longs, un accord modèle/mesures est observé. Cet écart peut être dû à un ΔIVOC/ΔCO ratio d’émission bas ou une sous-estimation basse des constantes d’oxydations des IVOCs, ce qui met en évidence la nécessité de poursuivre les études sur le terrain et dans les laboratoires de ces composés. / Atmospheric aerosols (i.e. particulate matter or PM) are a major source of uncertainty in climate models. Many studies have also shown that elevated concentrations of PM reduce life expectancies. Secondary organic aerosol (SOA) is formed in the atmosphere from gaseous precursors through chemical reactions and SOA represents a major component of PM mass globally. To better understand the chemical pathways responsible for SOA formation, a box model is designed to simulate dynamically the evolution of organic species in an air parcel as it undergoes photochemical oxidation producing SOA. The model incorporates recently published parameterizations for the formation of SOA from volatile organic compounds (VOCs), as well as from semi-volatile and intermediate-volatility organic compounds (SVOCs and IVOCs). The model is constrained by several measurements of precursors, including recently developed measurements that provide greatly improved constraints on precursor concentrations, and the predications are compared against measurements of SOA taken during the CalNex campaign. When accounting for the effect of chamber wall-losses on VOC yields, the amount and rate of SOA formation in the model is more consistent with observations. The results of this study also indicate that the primary SVOCs and IVOCs are responsible for a majority (70 – 86 %) of the model SOA mass, emphasizing their high contribution as SOA precursors. However, the SOA mass predicted is underestimated at shorter photochemical ages when compared to field measurements, but at longer ages, model/measurement agreement is observed. This bias may be due to low IVOC/CO emissions ratios or low estimated IVOC oxidation rate constants, which highlights the need for further field and laboratory studies of these compounds.

<p style="text-align: justify;">Извршено је моделирање и имплементација&nbsp;система који омогућава претраживање и&nbsp;преузимање библиотечких записа по&nbsp;дефинисаним стандардима. Систем је базиран&nbsp;на сервис-оријенисаној архитектури и&nbsp;mediator/wrapper шаблону. Систем је&nbsp;имплементиран у програмском језику Java, а&nbsp;модел је приказан у UML 2.0 нотацији. У&nbsp;оквиру система развијени су сервиси који&nbsp;представљају серверске стране за протокол&nbsp;Z39.50 и SRU и развијена је посебна&nbsp;софтверска компонента која омогућава&nbsp;интеграцију тих сервиса са постојећим&nbsp;библиотечким системом. Верификација овог&nbsp;система извршена је интеграцијом у&nbsp;софтверски систем БИСИС верзије 4.&nbsp;</p><p style="text-align: justify;"><br />Такође, показано је да се упит формиран&nbsp;помоћу Z39.50 упитног језика може&nbsp;трансформисати у упит који је дефинисан SRU&nbsp;упитним језиком. Дата је и трансформација&nbsp;SRU упитног језика у Lucene упитни језик. Дат&nbsp;је предлог проширења SRU стандарда у циљу&nbsp;да се овај стандард користи и за комуникацију<br />између клијента и сервера када је потребно&nbsp;снимање података у удаљену базу података.</p> / <p style="text-align: justify;">Izvršeno je modeliranje i implementacija&nbsp;sistema koji omogućava pretraživanje i&nbsp;preuzimanje bibliotečkih zapisa po&nbsp;definisanim standardima. Sistem je baziran&nbsp;na servis-orijenisanoj arhitekturi i&nbsp;mediator/wrapper šablonu. Sistem je&nbsp;implementiran u programskom jeziku Java, a&nbsp;model je prikazan u UML 2.0 notaciji. U&nbsp;okviru sistema razvijeni su servisi koji&nbsp;predstavljaju serverske strane za protokol&nbsp;Z39.50 i SRU i razvijena je posebna&nbsp;softverska komponenta koja omogućava&nbsp;integraciju tih servisa sa postojećim&nbsp;bibliotečkim sistemom. Verifikacija ovog&nbsp;sistema izvršena je integracijom u&nbsp;softverski sistem BISIS verzije 4.&nbsp;</p><p style="text-align: justify;"><br />Takođe, pokazano je da se upit formiran&nbsp;pomoću Z39.50 upitnog jezika može&nbsp;transformisati u upit koji je definisan SRU&nbsp;upitnim jezikom. Data je i transformacija&nbsp;SRU upitnog jezika u Lucene upitni jezik. Dat&nbsp;je predlog proširenja SRU standarda u cilju&nbsp;da se ovaj standard koristi i za komunikaciju<br />između klijenta i servera kada je potrebno&nbsp;snimanje podataka u udaljenu bazu podataka.</p> / <p> Modeling and implementation of software system for retrieval of bibliographic records using defined standard has been done. System is based on service &ndash; oriented architecture as well as on mediator/wrapper architecture. System implementation is realized in programming language Java and modelling of system is performed using UML 2.0. Also, services presenting server side of protocols Z39.50 and SRU have been developed. In addition, software component based on mediator approach used for connecting services for retrieval with legacy system is developed. Verification of described system is done by integration of that system into library system BISIS, version 4. Moreover, it is proved that transformations of Z39.50 query into SRU query are possible, and it has been made a suggestion how to transform SRU query into Lucene query. Also, it has been made suggestion how to extend existing SRU standard in order to use that extension when it is necessary to update bibliographic records on remote databases via Internet.</p>

Today’s market competitiveness and globalisation are putting pressure on organisations to join their efforts, to focus more on cooperation and interaction and to add value to their businesses. That is, most information systems supporting these cross-organisations are characterised as service-oriented business applications, where all the emphasis is put on inter-service interactions rather than intra-service computations. Unfortunately for the development of such inter-organisational service-oriented business systems, current service technology proposes only ad-hoc, manual and static standard web-service languages such as WSDL, BPEL and WS-CDL [3, 7]. The main objective of the work reported in this thesis is thus to leverage the development of service-oriented business applications towards more reliability and dynamic adaptability, placing emphasis on the use of business rules to govern activities, while composing services. The best available software-engineering techniques for adaptability, mainly aspect-oriented mechanisms, are also to be integrated with advanced formal techniques. More specifically, the proposed approach consists of the following incremental steps. First, it models any business activity behaviour governing any service-oriented business process as Event-Condition-Action (ECA) rules. Then such informal rules are made more interaction-centric, using adapted architectural connectors. Third, still at the conceptual-level, with the aim of adapting such ECA-driven connectors, this approach borrows aspect-oriented ideas and mechanisms, and proposes to intercept events, select the properties required for interacting entities, explicitly and separately execute such ECA-driven behavioural interactions and finally dynamically weave the results into the entities involved. To ensure compliance and to preserve the implementation of this architectural conceptualisation, the work adopts the Maude language as an executable operational formalisation. For that purpose, Maude is first endowed with the notions of components and interfaces. Further, the concept of ECA-driven behavioural interactions are specified and implemented as aspects. Finally, capitalising on Maude reflection, the thesis demonstrates how to weave such interaction executions into associated services.

This thesis is an exploration of the symbolic dimensions of activism in the SOA Watch movement, which seeks to close the School of the Americas (SOA), a U.S. training facility for Latin American military and police. Through historical analysis, participant observation, and ethnographic interviews with activists, I examine the practices of activism in the SOA Watch movement and the systems of meaning that inform them. As activists in the movement engage a system of power they seek to change, they construct and locate this system in space and time. By inserting themselves into the history and geography of the SOA through practices of resistance, activists construct and enact their own agency.

An interoperability gap exists between Learning Management Systems (LMSs) and Learning Object Repositories (LORs). Learning Objects (LOs) and the associated Learning Object Metadata (LOM) that is stored within LORs adhere to a variety of LOM standards. A common LOM standard found in LORs is the Sharable Content Object Reference Model (SCORM) Content Aggregation Model (CAM). In contrast, LMSs are independent computer systems that manage and deliver course content to students via a web interface. This research addressed three important issues related to the interoperability gap: (a) a lack of a metadata standard that defined the format of how student assessment data should be communicated from LMSs to LORs, (b) a lack of an architectural standard for the movement of data from LMSs to LORs, and (c) a lack of middleware that facilitated the movement of the student assessment data from the LMSs to LORs. This research achieved the following objectives: (a) the SCORM CAM LOM standard was extended to facilitate the storage of student assessment data, (b) Service Oriented Architecture (SOA) was identified as the best architecture to resolve the interoperability gap between LMSs and LORs, (c) a panel of Computer Information Systems (CIS) experts participated in a five-stage, web-based, anonymous Delphi process that approved and ranked 28 functional requirements for a proposed middleware application, and (d) the functional requirements were verified via the development of a prototype that transferred student assessment data from a LMSs into the LOM of LOs that are stored within a LOR. In conclusion, the research demonstrated that there are three acceptable approaches to extending the SCORM LOM standard: (a) new metadata elements, (b) new vocabulary values, and (c) the reference of an internal or external XML file using a location element. The main accomplishments of the research were the gathering of SOA functional requirements and the development of a prototype that provided an approach for the resolution of the interoperability gap that exists between LMSs and LORs.

First responders are continuously moving at an incident site and this movement requires them to access Service-Oriented Architecture services, such as a Web Map Service, via mobile wireless networks. First responders from inside a building often have problems in communicating to devices outside that building due to propagation obstacles. Dynamic user geometry and the propagation conditions of communicating from inside buildings to transceivers on the outside are difficult to model reliably in network planning software. Thus, leading commercial network simulation software and open source network simulator software do not model wireless links between transceivers inside and outside of buildings; new modeling software is needed. The discrete simulation runs in this investigation were built on events in a scenario that is typical of first-responder activities at an incident site. This scenario defined the geometry and node characteristics that were used in a mobile wireless network simulation to calculate expected connectivity based on propagation modeling, transceiver characteristics, and the environment. The author implemented in software a propagation model from the United States National Institute of Standards and Technology (NIST) to simulate radio wave propagation path loss during the scenario. Modifications to the NIST model propagation path loss method were generated to improve consistency in results calculated with the same node separation distances and radio wave obstacle environments. The final set of modifications made the NIST model more generalized by using more building material characteristics than the original version. The modifications in this study to the path loss model from NIST engineers were grounded on ad hoc network connectivity data collected at the operational scenario site. After changes in the NIST model were validated, 1,265 operational simulation runs were conducted with different numbers of deployed nodes in an operational incident-response scenario. Data were reduced and analyzed to compare measures of mobile ad hoc network effectiveness. Findings in this investigation resulted in two specific contributions to the body of knowledge in mobile wireless network design. First, data analysis indicated that specific changes to a recent path loss model from NIST produced results that were more generalized than the original model with respect to accommodating different building materials and enhancing the consistency of simulation results. Second, the results from the modified path loss model revealed an operational impact in using relay nodes to support public safety. Specifically, placing relay nodes at the entrance to a building and on odd-numbered floors improved connectivity in terms of first responders' accessing Web Services via mobile network devices, when moving through a building in an incident scenario.

Le travail de thèse porte sur une étude d'impact de différentes structures SOA sur la transmission optique de signaux OFDM modulés en intensité et reçus en détection directe (IMDD-OOFDM), dans le cadre des réseaux d'accès de nouvelle génération (σGPτσ). Dans la première partie du travail, nous avons d’abord validé expérimentalement la modélisation d’un RSτA sur une large plage d’utilisation. Ce modèle a ensuite été implémenté dans le cadre d'une plate-forme de co-simulation pour les systèmes de transmission IMDD-OOFDM et pour la conversion en longueur d'onde de signaux OOFDM avec une validation expérimentale. Une analyse approfondie des performances de transmission a été ensuite menée en termes de puissance optique et de longueur d’onde injectées, de longueur de fibre, de l’émission spontanée amplifiée (ASE), de la bande passante électrique et des non-linéarités du RSτA. Nous avons notamment montré théoriquement qu’une capacité minimale de transmission de 8,9 Gb/s sur 100 km pouvait être atteinte sur une plage de 100 nm avec le RSOA utilisé et avec l’aide d’une modulation adaptative (AMττFDM). Nous avons également démontré expérimentalement, pour la première fois à notre connaissance, la conversion de longueur d'onde de signaux optiques OOFDM-16QAM sur une plage de 70 nm en utilisant l'effet XGM du RSOA. Dans la seconde partie, nous avons développé la modélisation de plusieurs structures de SOA : un SOA à îlots quantiques (QD SOA), un SOA bi-électrodes et deux SOA cascadés en configuration contra-propagative. Nous avons étudiés leurs performances en transmission à l’aide de la modulation AMττFDM. Nous avons montré que ces structures présentent une capacité de transmission allant jusqu’à 30 Gb/s avec des distances de transmission jusqu'à 60 km. Nous avons montré également que le QD-SOA présente de meilleures performances en termes de capacité de transmission pour des distances allant jusqu'à 140 km en comparaison avec les deux autres configurations. / The thesis work deals with study of different SOA structures impact on the transmission of intensity modulation and direct detection OFDM signals in the context of the next generation access networks. In the first part of the work, we have experimentally validated a comprehensive wideband RSOA field model. It was the nused as part of a co-simulation platform for IMDD-OOFDM and OOFDM wavelength conversion transmission systems. Thanks to this co-simulation platform that presents good agreement with the measurement, and our experimental setup, we analyze the transmission performance in terms of optical input power, fiber length, ASEnoise, electrical bandwidth and RSOA nonlinearities. We showed by simulation that an AMOOFDM signal transmission over a 100 nm wavelength range with a minimum transmission capacity of 8.9 Gb/s for fiber lengths up to 100 km can be reached. Finally, we experimentally demonstrated, for the first time to the best of our knowledge, the feasibility of performing wave length conversion over 70 nm of OOFDM-16QAM optical signals using the XGM effect in an RSOA. In the second part of this work we develop a simplified quantum dot –SOA and two electrode SOAintensity modulator models and study their effect on a numerical OFDM IMDD transmission system, we also study a two cascaded SOA in a counter propagating configuration as an intensity modulator. We find that for the three configurations we can achieve a high transmission capacity of around 30 Gb/s for transmission distances up to 60 Km, we also find that the QD-SOA will have the best performance in terms of transmission capacity for distances up to 140 Km in comparison with the two other SOA configurations.