Enhancement of the usability of SOA services for novice users

Recently, the automation of service integration has provided a significant advantage in delivering services to novice users. This art of integrating various services is known as Service Composition and its main purpose is to simplify the development process for web applications and facilitates reuse of services. It is one of the paradigms that enables services to end-users (i.e.service provisioning) through the outsourcing of web contents and it requires users to share and reuse services in more collaborative ways. Most service composers are effective at enabling integration of web contents, but they do not enable universal access across different groups of users. This is because, the currently existing content aggregators require complex interactions in order to create web applications (e.g., Web Service Business Process Execution Language (WS-BPEL)) as a result not all users are able to use such web tools. This trend demands changes in the web tools that end-users use to gain and share information, hence this research uses Mashups as a service composition technique to allow novice users to integrate publicly available Service Oriented Architecture (SOA) services, where there is a minimal active web application development. Mashups being the platforms that integrate disparate web Application Programming Interfaces (APIs) to create user defined web applications; presents a great opportunity for service provisioning. However, their usability for novice users remains invalidated since Mashup tools are not easy to use they require basic programming skills which makes the process of designing and creating Mashups difficult. This is because Mashup tools access heterogeneous web contents using public web APIs and the process of integrating them become complex since web APIs are tailored by different vendors. Moreover, the design of Mashup editors is unnecessary complex; as a result, users do not know where to start when creating Mashups. This research address the gap between Mashup tools and usability by the designing and implementing a semantically enriched Mashup tool to discover, annotate and compose APIs to improve the utilization of SOA services by novice users. The researchers conducted an analysis of the already existing Mashup tools to identify challenges and weaknesses experienced by novice Mashup users. The findings from the requirement analysis formulated the system usability requirements that informed the design and implementation of the proposed Mashup tool. The proposed architecture addressed three layers: composition, annotation and discovery. The researchers developed a simple Mashup tool referred to as soa-Services Provisioner (SerPro) that allowed novice users to create web application flexibly. Its usability and effectiveness was validated. The proposed Mashup tool enhanced the usability of SOA services, since data analysis and results showed that it was usable to novice users by scoring a System Usability Scale (SUS) score of 72.08. Furthermore, this research discusses the research limitations and future work for further improvements

Supporting complex work in crowdsourcing platforms: a view from service-oriented computing

Today, crowdsourcing is changing the way people work and solve problems - from ”in-house working” to ”public outsourcing”. Many online crowdsourcing platforms allow the requester to advertise their tasks and help crowd workers find their jobs. However, those platforms mainly focus on the micro-task market and do not support the complex work consisting of interdependent, professional tasks. To crowdsource this work, we need a way to model professional workers, define the complex task, and a coordination mechanism to manage them. To this end, we propose a service-oriented crowdsourcing framework in this thesis wherein (1). Each professional crowd worker is modelled as a service that can be self-described, dynamically discovered and assembled into the complex crowd work; (2). A complex crowd task is defined as a schema consisting of a set of units of work and their inter-dependencies, which can be used to get multiple crowd workers involved and guide their work; (3). The whole crowdsourcing lifecycle is divided into two phases: (i). Plan Phase - where the working plan on the advertised complex task is crowdsourced to generate the schema as mentioned earlier detailing the original advertising; and subsequently, this schema is transformed into a web service orchestration specification for the later auto-coordination; (ii). Execution Phase - where the execution of the planning result is crowdsourced to complete the original complex work as advertised through coordinating and interacting with multiple crowd workers, based on coordination and interaction protocol

Serviços orientados a eventos da vida controlados pelo cidadão

Doutoramento em Engenharia InformáticaA progressiva introdução das Tecnologias da Informação e Comunicação na Administração Pública (AP) provocou uma grande evolução na prestação de serviços ao cidadão. Transitou-se de um paradigma de prestação de serviços baseado nas competências de cada instituição, resultado da organização da AP em silos, para um paradigma de prestação de serviços integrados, que pode envolver a participação de serviços de várias instituições, que para o efeito trocam informação entre si, porventura sem que o cidadão disso se aperceba. Um dos objetivos da integração de serviços é a prestação de serviços que visam satisfazer situações do dia-a-dia do cidadão que implicam a interação com serviços da AP, i.e., serviços orientados a eventos da vida (serviços OEV). No entanto, apesar da bondade do objetivo, a integração de serviços é complexa e tem o potencial para criar situações desfavoráveis para o cidadão, nomeadamente para sua privacidade. Com efeito, o cidadão deixa de ter o controlo sobre a difusão da sua informação pelas várias instituições, uma vez que são estas que comunicam entre si para obter a informação necessária para a prestação dos respetivos serviços. Nesta tese propomos um modelo de prestação de serviços OEV, o modelo CHAPAS, que pretende: (i) desincentivar a comunicação direta entre instituições para a obtenção de informação do cidadão, (ii) colocar o cidadão no controlo da disseminação da sua informação pelas várias instituições e (iii) fomentar a minimização da informação que o cidadão tem de fornecer às várias instituições para obter os serviços que pretende. Para cumprir esses objetivos, transferimos para o cidadão a responsabilidade pela obtenção de todos os serviços que compõem um serviço OEV, e dotámos o cidadão de uma aplicação, o Chappie, que lhe permite: (i) compor o serviço OEV que pretende obter, (ii) verificar que informação tem de fornecer para obter cada um dos serviços que compõem o serviço OEV e, caso o cidadão assim o decida, (iii) proceder à obtenção desses vários serviços. Como o cidadão pode fornecer a cada instituição toda a informação necessária para que esta lhe preste o serviço pretendido, mesmo que tenha de os obter previamente de outras instituições, estas deixam de ter necessidade de comunicar entre si para obter a informação que necessitam para a prestação dos respetivos serviços, o que permite limitar a difusão de informação do cidadão e dessa forma proteger a sua privacidade. Para a avaliação do modelo usámos o evento da vida de compra de casa, que envolve interações do cidadão com serviços de várias instituições da AP e particulares e cujas características nos permitem explorar as várias vertentes do modelo. Com base nele, desenvolvemos um cenário de exploração e protótipos do Chappie e dos vários serviços, que nos permitiram concluir da viabilidade do modelo CHAPAS, com algumas vantagens e com algumas limitações, para ser uma alternativa viável para a prestação de serviços de governo eletrónico ao cidadão.The introduction of Information and Communication Technologies in the Public Administration (PA) gave rise to a huge evolution in the provisioning of public services to the citizen. It evolved from a service provisioning paradigm based in the competences of each PA department, which directly results from the PA siloed organization, into an integrated service provisioning paradigm, that may involve multiple PA departments that exchange information with each other, possibly without the citizen being aware of those exchanges. One of the reasons for this service integration is the provisioning of better services targeted to the satisfaction of citizens’ everyday situations that require interaction with many PA services, i.e., life-event services. Despite the goodness in the goal of improving the citizen interaction with PA, the integration of PA services is complex and may create adverse situations for the citizens, namely regarding their privacy. The citizen loses the control over the dissemination of his personal information throughout the many PA departments, as they communicate with each other to gather the information required for service provisioning. In this thesis, we propose a model for life-event service provision, the CHAPAS model, with the following goals: (i) to discourage direct communication between PA departments to exchange citizens’ information; (ii) to place the citizen in control of the dissemination of his information throughout the many PA departments; and (iii) to promote the minimization of the disclosure of citizens’ information to PA departments when obtaining the wanted services. To fulfill these goals, we transfer the responsibility for obtaining all the partial services that composes a life event service to the citizen that is empowered with an application, the Chappie, which enables him to: (i) compose the life-event service he wants; (ii) verify the information he must disclose to obtain each and every partial service that composes the life-event service he wants; and upon a citizen decision, (iii) obtain all those partial services. As the citizen is able to supply all the information that a PA department needs to provide the service the citizen wants, departments no longer need to communicate with each other to gather the information they need for service provisioning. This enhances the protection of citizens’ privacy as we avoid the dissemination of citizens’ information without his control. For CHAPAS model validation, we used the Buying a Home life event, which requires citizen interactions with services from several PA departments and private institutions, and whose characteristics allows for a full exploration of the model. We developed an exploitation scenario and prototypes for the citizen Chappie and for the several services from which we concluded that the CHAPAS model, with some advantages and some disadvantages, might be a viable alternative for the provisioning of e-government services to citizens