Made available in DSpace on 2016-12-23T14:33:47Z (GMT). No. of bitstreams: 1 dissertacao_thiago_paris_salviato_parte1.pdf: 1508915 bytes, checksum: 3962eeec95712d8f523e5fb7965e6e9b (MD5) Previous issue date: 2012-01-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aplicações sensíveis ao contexto usam informações contextuais para customizar serviços de acordo com as situações e as necessidades dos seus usuários. Um dos cenários promissores para o desenvolvimento dessa classe de aplicações é aquele proporcionado pelo ambiente de televisão digital interativa, em particular no âmbito do Sistema Brasileiro de Televisão Digital (SBTVD). Apesar de apresentar funcionalidades que facilitam o desenvolvimento dessas aplicações, como o suporte à adaptação da apresentação de conteúdo dependendo do valor de variáveis de ambiente e suporte a múltiplos dispositivos, o Ginga, padrão de middleware do SBTVD, ainda carece de uma infraestrutura de gerenciamento de contexto mais adequada ao suporte de aplicações desse tipo mais elaboradas, independentes de domínio e voltadas ao reuso. Dentre os diversos desafios de se construir essa infraestrutura, dotar o Ginga de um serviço genérico de aquisição de informações contextuais pode ser uma tarefa desafiadora, particularmente devido à natureza heterogênea dos dispositivos de captura de contexto utilizados e das informações variadas por eles obtidas. A partir de uma proposta de arquitetura conceitual genérica para o módulo Gerenciador de Contexto do Ginga, definida em projeto anterior, o trabalho apresenta a implementação do componente Gerenciador de Fontes de Contexto , elemento da arquitetura cuja função é prover uma interface padronizada para a comunicação entre o middleware e dispositivos heterogêneos responsáveis pela aquisição de informações contextuais. A implementação realizada baseia-se na utilização de scripts NCLua, linguagem imperativa do padrão, e no OSGI, framework de gerenciamento de dispositivos para home networks. O trabalho propõe ainda uma metodologia para o desenvolvimento de aplicações sensíveis ao contexto utilizando a infraestrutura desenvolvida / Context-aware applications use contextual information to customize services according to the dynamicity of the situations and needs of its users. One of the promising scenarios for the development of this class of applications is that provided by the interactive digital television, particularly in the context of the Brazilian Digital Television System (SBTVD). Even though it presents features which can be used to facilitate the development of context-aware applications, such as content presentation adaptation and multiple devices support, the current middleware standard for the SBTVD, named Ginga, still lacks a context management infrastructure that favors the development of complex, domain independent and designed to reuse context-aware applications. Among the many challenges of building this infrastructure, providing Ginga with a generic service for the acquisition of contextual information can be a major task, particularly due to the heterogeneous nature of context sources devices and their varying data. Starting from a generic conceptual architecture defined for the Ginga s Context Manager component in a earlier project, this work presents an implementation for the Context Sources Manager , a key element of architecture, whose responsibility is to provide a standardized interface for the communication between the middleware and the heterogeneous devices that are responsible for the acquisition of contextual information. The implementation is carried out based on the use of scripts NCLua, the Ginga s imperative language, and OSGI, a framework for the management of electronic devices in home networks. The dissertation also proposes a new methodology for the development of context-aware applications using the developed infrastructure

Made available in DSpace on 2014-07-29T14:57:51Z (GMT). No. of bitstreams: 1 dissertacao-rodrigohs.pdf: 1383844 bytes, checksum: b3fda2012ce5a20dc390677f308520e3 (MD5) Previous issue date: 2012-05-29 / Context models that describe dynamic context-aware scenarios usually need to be frequently updated. Some examples of situations that motivate these updates are the appearance of new services and context providers, the mobility of the entities described in these models, among others. Generally, updates on models imply redevelopment of the architectural components of context-aware systems based on these models. However, as these updates in dynamic scenarios tend to be more frequent, it is desirable that they occur at runtime. This dissertation presents an infrastructure for dynamic management of context models based on the fundamentals of complex event processing, or CEP. This infrastructure allows the fundamental abstractions from which a model is built to be updated at runtime. As these updates can impact systems based on the updated models, this dissertation identifies and analyzes these impacts, which are reproduced in a case study that aims to evaluate the proposed infrastructure by demonstrating how it deals with the impacts mentioned. / Modelos contextuais que descrevem cenários de computação sensível ao contexto dinâmicos normalmente precisam ser frequentemente atualizados. Alguns exemplos de situações que motivam essas atualizações são o surgimento de novos serviços e provedores de informações contextuais, a mobilidade das entidades descritas nesses modelos, dentre outros. Normalmente, atualizações em modelos implicam em redesenvolvimento dos componentes arquiteturais dos sistemas sensíveis ao contexto baseados nesses modelos. Porém, como em cenários dinâmicos essas atualizações tendem a ser mais frequentes, é desejável que elas ocorram em tempo de execução. Essa dissertação apresenta uma infraestrutura para gerenciamento dinâmico de modelos de contexto baseada nos fundamentos de processamento complexo de eventos, ou CEP. Essa infraestrutura permite que as abstrações fundamentais a partir das quais um modelo é construído sejam atualizadas em tempo de execução. Como essas atualizações podem causar impactos nos sistemas baseados nos modelos atualizados, essa dissertação identifica e analisa esses impactos, os quais são reproduzidos em um estudo de caso que tem como finalidade avaliar a infraestrutura proposta através da demonstração de como ela lida com os impactos mencionados.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A computaÃÃo ubÃqua à um paradigma computacional de grande abrangÃncia, com aplicabilidades tanto para o cotidiano de um cidadÃo comum quanto para o tratamento de informaÃÃes complexas em ambientes hospitalares. Este paradigma propÃe uma nova forma de interaÃÃo homem-computador baseada na proatividade dos computadores para facilitar a vida dos usuÃrios. Entretanto, tal forma de interaÃÃo demanda um alto grau de colaboraÃÃo e comunicaÃÃo entre os elementos computacionais que compÃem os ambientes mÃveis e ubÃquos. Um dos principais desafios està relacionado a maneira de como conceber sistemas de software capazes de lidar com a alta variaÃÃo de recursos e serviÃos, alÃm de garantir a interoperabilidade entre os diversos elementos computacionais que compÃem estes ambientes. Este trabalho propÃe, entÃo, um middleware adaptativo para ambientes mÃveis e ubÃquos com o objetivo de solucionar problemas de heterogeneidade e dinamicidade. Para diminuir o acoplamento entre o middleware proposto e as aplicaÃÃes que o utilizam, esta dissertaÃÃo tambÃm propÃe um processo de composiÃÃo de software. O middleware utiliza mecanismos de adaptaÃÃo dinÃmica e suporte ao desenvolvimento de software sensÃvel ao contexto, e o processo de composiÃÃo faz uso de tÃcnicas de ProgramaÃÃo Orientada a Aspectos (POA). Um estudo de caso à desenvolvido para avaliar a funcionalidade do middleware adaptativo e demonstrar a utilizaÃÃo do processo de composiÃÃo. AlÃm disso, uma anÃlise de desempenho à apresentada para medir o impacto provocado pelo uso do middleware proposto em um ambiente de rede sem fio. / Ubiquitous computing is an extensive computational paradigm, which can provide solutions to regular citizens or can be useful to handle complex medical environment data, for example. This paradigm proposes a new human-computer interaction approach based on the proactivity of computers that makes usersâ life easier. However, this approach demands a high level of collaboration and communication among the computational elements that compose the mobile and ubiquitous environments. One of the main challenges is related to the way of conceiving software systems capable of dealing with the high variation of resources and services, along with guaranteeing the interoperability among the diversity of computational elements that compose these environments. Therefore, this work proposes an adaptive middleware for mÃbile and ubiquitous environments that intends to solve heterogeneity and dynamicity problems. This dissertation also proposes a software composition process to reduce coupling between the proposed middleware and applications. The middleware uses dynamic adaptation and support for context-aware software development mechanisms, and the composition process uses Aspect-Oriented Programming (AOP) techniques. A case study is developed to evaluate the adaptive middlewareâs functionalities and demonstrate the composing process. Furthermore, a performance analysis is presented to measure the proposed middlewareâs impact in a wireless network.

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-09-23T12:05:51Z No. of bitstreams: 2 Dissertação - Guilherme Silva Marques - 2016.pdf: 2715063 bytes, checksum: 3bafbdca7ace292dda958959884eaeb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-26T12:00:37Z (GMT) No. of bitstreams: 2 Dissertação - Guilherme Silva Marques - 2016.pdf: 2715063 bytes, checksum: 3bafbdca7ace292dda958959884eaeb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-26T12:00:37Z (GMT). No. of bitstreams: 2 Dissertação - Guilherme Silva Marques - 2016.pdf: 2715063 bytes, checksum: 3bafbdca7ace292dda958959884eaeb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-09-05 / Dey et al. [10] define context as the information set that can be used to characterize the status of an entity (e.g. person, place or object relevant to the user-application interaction). Perera et al. [36] propose a context information life cycle in 4 phases: acquisition, modeling, reasoning and dissemination. Context modeling consists in representing the real world in computing and, according to Bettini et al. [2], a good information context modeling mitigates the complexity of context-aware applications. In the context of this work, a systematic review demonstrated that the literature has focused on context information modeling, but with less emphasis on the architectural project. The main problem addressed on this work is the creation and evaluation of architectural projects that work together on the context modeling phase of a Semantic Context-Aware System (SCAS), which uses ontologies as main information modeling technique. This work proposes an architectural solution to two relevant services of the ontology-based context modeling phase: the former represents context information collected through sensors, and the latter aggregates context information represented by the former for a same individual or entity. Both architectural designs were built using well-known architectural styles and design patterns, as well as were evaluated against architectural designs of similar projects. As a result, the main contributions include the architectural designs of ontology-based services for context representation and aggregation as references for the development of SCAS in terms of the context modeling phase. / Contexto é o conjunto de informações que pode ser utilizado para caracterizar a situação de uma entidade (pessoa, lugar ou objeto relevante para a interação usuário-aplicação) [10]. Perera et al. [36] propõem um ciclo de vida para a informação de contexto composto por 4 etapas: aquisição, modelagem, raciocínio e disseminação. A etapa de modelagem de contexto consiste em representar o mundo real na computação. Segundo Bettini et. al. [2] “uma boa modelagem de informação de contexto reduz a complexidade das aplicações sensíveis a contexto”. Um Sistema Sensível ao Contexto Semântico (SSCS) é um sistema computacional que utiliza ontologias que, segundo Gruber [15], é “uma especificação explícita de uma conceitualização”, e consistem em uma das formas de modelar as informações de contexto. Como resultado de uma revisão sistemática feita pelo autor deste trabalho evidenciou que na literatura o foco dos trabalhos tem sido na modelagem da informação de contexto com menor enfoque no uso de projeto arquitetural. Com base nisso, o principal problema endereçado neste trabalho é a criação e avaliação dos projetos arquiteturais que trabalhem em conjunto na modelagem do ciclo de vida de contexto em SSCS. Objetiva-se elaborar uma solução arquitetural para sistemas sensíveis ao contexto semântico baseado em ontologias. Propôs-se neste trabalho o projeto arquitetural para o software de representação ontológica de contexto e para o software de agregação ontológica de contexto. O primeiro representa as informações coletadas através de sensores e o segundo agrega as informações representadas para um mesmo indivíduo ou entidade. Realizou-se, assim, a avaliação dos projetos arquiteturais propostos e explana-se sobre os resultados obtidos, comparando-os com outros projetos existentes na literatura. Com a obtenção dos resultados propostos, espera-se contribuir com a literatura, apresentando projetos arquiteturais e avaliações destes, auxiliando, assim, o desenvolvimento de SSCS no que se refere à modelagem do ciclo de vida de contexto.

Made available in DSpace on 2016-08-17T14:52:38Z (GMT). No. of bitstreams: 1 Dissertacao_Renato Ubaldo Moreira e Moraes.pdf: 1378349 bytes, checksum: c8d418a48e72c6d94fdc632323dcf508 (MD5) Previous issue date: 2014-09-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nowadays, there was a massive inclusion of smart mobile devices, known as smartphones, and with this accession, there s consequently a large increase in the consumption of information, especially from the internet. To support the great demand for information access, it s created a numerous devices to facilitate both access, the creation and the storage of such information, among the best known and disseminated currently is cloud computing. The feedback takes currently, an increasingly important and even critical for some entities, size and value turns out to be very desirable. Being often target capture and espionage attempts. To obtain data confidential information hackers use numerous devices, and more is used to scan networks. In other words can be described as scan "Scans notifications in computer networks, in order to identify which computers are active and which services are available for them. It is widely used by attackers to identify potential targets because it allows associate potential vulnerabilities to services enabled on a computer " [10]. According to [10] the number of attacks has been widening each year as shown in Figure 1.1 and 1.2 which are in section 1.1. Based on this high number incidents, the growth of the information consumer by means of devices furniture and the need to improve energy costs, the proposed establishment of the Office Security for Context Aware of authentication (Serviço de Segurança para Autenticação Ciente do Contexto(SSACC)) is required for today. The ssacc focus to provide a secure channel for transfer files to a server, using context information and reducing energy waste, thus saving resources and framing the Green Computing. Made based on the Secure Socket Layer (SSL), which is a widely used protocol that provides secure communication through a network. It uses several different cryptographic processes to ensure that data sent through the network is secure. It provides a security enhancement for the Transport Control Protocol (TCP) / Internet Protocol (IP) standard, which is used for communication with the Internet. SSL uses public key cryptography to provide authentication. The SSL protocol also uses encryption of the private key and digital signatures to ensure privacy and the integrity of data " [26]. / Atualmente houve uma adesão em massa aos dispositivos móveis inteligentes, conhecidos como smartphones, e, com essa adesão, houve consequentemente um grande aumento no consumo da informação, principalmente proveniente da internet. Para atender a grande demanda de acesso à informação foi criado inúmeros artifícios para facilitar tanto o acesso, quanto a criação e o armazenamento dessas informações, dentre os mais conhecidos e difundidos atualmente está a computação em nuvem. A informação assume, hoje em dia, uma importância crescente e até vital para algumas entidades, e com tamanho valor acaba se tornando muito desejada, sendo muitas vezes alvo de tentativas de captura e espionagem. Para se obter dados de informações confidenciais hackers usam inúmeros artifícios, e o mais usado é o scan de redes, que em outras palavras pode ser descrito scan como "notificações de varreduras em redes de computadores, com o intuito de identificar quais computadores estão ativos e quais serviços estão sendo disponibilizados por eles. É amplamente utilizado por atacantes para identificar potenciais alvos, pois permite associar possíveis vulnerabilidades aos serviços habilitados em um computador" [10]. De acordo com o [10] o número de ataques só vem crescendo a cada ano como mostra a figura 1.1 e 1.2 que estão na seção 1.1. Com base nesse alto número de incidentes, o crescimento do consumo da informação por meio de dispositivos móveis e a necessidade de melhorar gastos de energia, a proposta de criação do Serviço de Segurança para Autenticação Ciente do Contexto (SSACC) é necessária para a atualidade. O SSACC tem como principal objetivo fornecer um canal seguro para transferência de arquivos para um servidor, fazendo uso de informações de contexto e diminuindo o desperdício de energia, consequentemente economizando recursos e se enquadrando à Computação Verde. Feito com base no Secure Socket Layer(SSL), que é um "protocolo amplamente utilizado que fornece comunicação segura através de uma rede. Ele usa vários processos criptográficos diferentes para garantir que os dados enviados por meio de rede são seguras. Ele fornece um aprimoramento de segurança para o protocolo Transport Control Protocol (TCP)/ Internet Protocol (IP) padrão, que é usado para comunicação com a internet. SSL utiliza criptografia de chave pública para fornecer autenticação. O protocolo SSL também usa criptografia de chave privada e assinaturas digitais para garantir a privacidade e a integridade dos dados" [26].

[pt] A difusão das redes sem fio IEEE 802.11 e o avanço das técnicas de posicionamento baseadas na força de sinal de rádio frequência (RF) (e.g., sensores, algoritmos de triangulação, etc.) têm motivado o desenvolvimento de aplicações e serviços sensíveis ao contexto e sua localização (Location Based Services). Essas aplicações oferecem vários benefícios para os usuários finais, por exemplo, adaptação às limitações dos dispositivos e da rede sem fio, acesso às informações de localização, ou a capacidade de enviar notificações baseadas na localização ou na proximidade entre os usuários (e.g., Geocaching). Entretanto, há dois desafios principais relacionados ao desenvolvimento e uso de aplicações sensíveis ao contexto: a complexidade em desenvolver os serviços de provisão de contexto e a necessidade de manter a privacidade da informação de contexto (e.g., localização) do usuário. Para auxiliar o desenvolvimento de aplicações sensíveis ao contexto, projetamos e implementamos alguns serviços que constituem o núcleo de uma arquitetura de provisão de contexto, chamada MoCA (Mobile Collaboration Architecture). Esses serviços implementam a coleta, o processamento e a difusão da informação de contexto através de interfaces de comunicação síncronas e baseadas em eventos. A MoCA serviu de base para o desenvolvimento da nossa pesquisa sobre privacidade na qual projetamos um serviço que auxilia o usuário no controle de privacidade das suas informações de contexto, em especial, da sua informação de localização. Como parte do nosso trabalho, definimos um modelo conceitual que serviu de base para o desenvolvimento do serviço de privacidade proposto (a ser utilizado por uma comunidade de usuários) e discutimos alguns requisitos que devem ser levados em conta no projeto de um serviço deste gênero. A maioria destes requisitos delinearam o projeto e implementação do Context Privacy Service (CoPS). Este serviço foi integrado aos serviços de provisão de contexto da arquitetura MoCA. / [en] The widespread dissemination of IEEE 802.11 networks and the enhancement of positioning techniques based on RF signal strength (e.g., sensors, positioning triangulation algorithms, etc) have fostered the development of location-based and context-aware services and applications. These applications offer several benefits to the end-users, e.g. adaptation to the device and wireless network limitations, access to location- specific information, or the ability to send location-specific notifications to other users (e.g., Geocaching). However, there are two main challenges concerning the development and use of context-aware applications: the complexity in developing context provisioning services and the need to guarantee the privacy of the users' context information (e.g., their location). In order to support the development of context-aware applications, we have designed and implemented some services that constitute the core of a context provisioning architecture called MoCA (Mobile Collaboration Architecture). These services implement the gathering, processing and diffusion of context information through synchronous and event-based communication interfaces. MoCA architecture has been used as a basis to the development of our research about privacy in which we have designed a service that aids the end-user in defining the privacy level for his/her contextual information, and in particular for his/her location information. As part of our work, we define the conceptual model underlying our privacy control service (targeted at a community of users) and discuss the most important requirements that should be conside- red in the design of such a service. Most of these requirements have guided the design and implementation of the Context Privacy Service (CoPS). This service has been integrated to the context provisioning services of the MoCA middleware.

Mobile technology is developing quickly and becomming a part of daily life and communication. Bluetooth Low Energy is presented as a new way of mobile interaction. However there are not enough studies in this field on the interaction between mobile devices and the physical world. In order to understand user needs, and to encourage users to interact, we simulated an interaction process through designing and testing a prototype in a specific indoor environment. Prototype effectiveness and main characteristics for future mobile application was evaluated through a qualitative user study with 20 participants who interacted with our prototype. / Den mobila tekniken växer snabbt och blir en del av våra liv och vår kommunikation. BLE presenteras på ett nytt sätt inom mobilinteraktion. Det förekommer inte tillräckligt med studier inom området för interaktionen mellan mobila enheter och den fysiska världen. För att förstå användarbehov och få användare att interagera har vi simulerat en interaktiv process genom att designa och testa en prototyp i en specifik inomhusmiljö. Utvärdering av prototypens effektivitet och heuristiken har evaluerats genom en kvalitativ studie med 20 användare som har deltagit i interaktionen med vår prototyp.

This work describes a design of a multimedia content delivery system based on context, to provide multimedia information and other services according to the user location and his preferences. It focuses on mobility and the problem of different coherent and cohesive presentations depending on the available resources of the presentation environment.

The technological advances in wireless networks, smart phones, social networks, embedded sensor technologies and the wide spread of mobile devices have exposed customers to number of services. With these advanced technological innovations, computing capability and connectivity, customers look forward to get useful services and information by means of their mobile devices anywhere and at anytime thereby saving time and money. The importance of mobile commerce is increasing every day, since the mobile devices are becoming central part of our lives. One of the challenge here is the ability to reinforce the application behavior by utilizing context information. The analysis and utilization of context information is necessary to build intelligent applications and thereby focusing on less user attention by understanding the current situation. The information about the current location of a mobile customer, the time of request, and personal characteristics like nature of work, profession and economic status are utilized by applications to provide accurate context-aware services. Many of context-aware applications focus mainly on user activity, preferences which are not sufficient to provide context-aware intelligent services. However, there are few works in developing an integrated model for analyzing the context information. Many authors describe the context representation using five elements like who, what, where, when and how to provide a user centric view without emphasizing on the feature of generality and structural representation of context parameters. Since context information takes multiple forms, it is essential and necessary to make broad classification which helps application designers and developers to deal with possible contexts and their impact on application behavior. In addition, the context classification enables to understand complex customer situations due to changing mobile environment. Therefore, it is required to design a model which analyzes the context information of customers in a dynamic environment and hence, provide real time accurate service. The design and development of context-aware mobile commerce services requires a general conceptual model which can handle any type of context information for different applications. Due to the dynamic nature of business environment and also the customer preferences keep emerging, there is a need to develop business model which adapts to changing environment. To understand the current situation of customers in such highly dynamic environments and to enable the business transactions quickly among parties involved, it is essential to construct and analyze an integrated view of information from distinct sources. The adaptation of the provided services based on customer needs depends when the relevant context information is self-described in the form of beliefs. The observations made on combination of context information are deduced into beliefs as a result the decision making time to provide service reduces considerably. The aim of the thesis, is to design and develop a context-aware system which has been applied for mobile commerce environment by considering the customer context information. To do this, we have designed two models: the Context-Information, Observation and Belief (C-IOB)model and the commercial business model. The main function of C-IOB model is to support the application to identify a suitable context-aware service and to execute business transaction for a customer by analyzing the context information in the form of beliefs. We classify the used Context Information(CI)into four types: physical, system, application and social environment. The business model discusses the formal description of participants who are involved in commercial business. The C-IOB model The Context Information, Observation and Belief model deduces beliefs on customer, by combination of available context information during transaction execution or service provision. The beliefs represent the various situations of customers based on specific nature of the applications. The beliefs developed about an entity(e.g. ,person, place, thing) are primitive in most theories of decision making so that applications can use these beliefs to identify and execute context-aware services. The C-IOB model reduces the solution search space, since the knowledge about an entity is organized using cognitive factors, which maps user context information into real world observations and beliefs, as a result the decision making time by the system reduces considerably. The five CI -constructs: who, what, where, when and how enable many types of context information acquisition in our work. The commercial business model A commercial business model mainly involves the formal description of business participants who are involved in commercial business transactions. To meet the growing needs and to fulfill high expectations of customers, it is very important that application designers have to address the issue of building viable business models for commercial environment. The business model describes how an enterprise or an organization captures and delivers economical value to customers. In particular, the customers play major role in transactions execution and hence understanding and identifying the needs of customer is an important issue in building the business model for commercial purpose. Mobile Commerce Environment Mobile commerce environment (MCE) is one of the specific forms of commercial business model. It deals with transactions like purchases with the objective of supplying commodities like goods and services to customers using mobile devices. A Mobile commerce environment is established by considering set of customers, vendors and bankers, who are involved in commercial business activities like buying of electronic goods and services. The environment is based on certain factors like the type of customers, the type of transactions and the type of electronic products involved in purchasing. M-commerce is one of the most effective and useful ways of conducting business as the customers are constantly using mobile devices and it significantly assists customers in making transactions anywhere, anytime and thereby improving the customer satisfaction. C-IOB model based mobile commerce environment Mobile commerce applications are required to be flexible, in providing services due to inherent anytime and anywhere paradigm. The traditional systems during commercial business transactions, take large time to search the right product, which leads to more utilization of device resources like memory and computational power. In addition, the users are striked with more information which is not significant. Therefore, there is a need to design applications, which identify the customer requirements by acquiring the context information from distinct sources and thereby providing timely and specific information or services to the customer. Hence, to adapt services based on various situations, it is required to develop a systematic approach for representation and utilization of context information modified to special characteristics of mobile commerce applications. The mobile commerce environment uses C-IOB model for analyzing the relevant context information of customers and the context based beliefs helps to identify a suitable service for an end customer, thereby reducing mobile transaction execution time and providing customer benefits. The simulation environment consists of 10,000 electronic products which are categorized based on technical and commercial features. The simulation is carried out with ten mobile commerce transactions, the database consists of information about500 customers and 100vendors who deal with electronic products selling and10bankersfor money transactions. The customer context information is acquired from physical, system, application and social environment. When customers ends are quest for a service, the current context information is acquired, a set of observations is formulated and belief is deduced. The customer is provided with relevant information or service based on deduced belief. The simulation exhaustively tests the working of the system for mobile commerce transactions under different context environments. Some of the case studies are designed by applying the C-IOB model which includes placing the purchase order for the product, money transfer and after sales service. In summary, we have developed a context-aware system by using C-IOB model and also the design of commercial business model. To evaluate the performance of the system, we have incorporated context-awareness aspect for 10 business transactions applied to mobile commerce. The proposed system using C-IOB model provides customer required services as accurately as possible. The system has the capability to adapt to real time situation of customer needs, thereby enhancing the customer satisfaction. The simulation results have shown that the time to execute mobile commerce transactions is less using context based beliefs compared to context unaware approach. The accuracy of the system with belief based approach is higher than without context information. The customer benefits in business transaction are also enhanced by our design approach.

[pt] Diversos sistemas e aplicações são capazes de identificar um determinado contexto de uso em tempo real, detectando informações para antecipar situações e otimizar sua interface. Esses sistemas que agem de forma contextual e, muitas das vezes, proativa pertencem à área da Computação ciente de contexto. O aplicativo Google para sistemas Android e IOS possui um serviço de assistente virtual para dispositivos móveis que utiliza dados da conta do usuário obtidos através dos serviços Google, além de dados do próprio dispositivo. O assistente é capaz de identificar hábitos, antever necessidades e oferecer cards de informações antes mesmo que sejam pedidos pelo usuário. Pertencendo ao campo da computação ciente de contexto, o aplicativo Google foi eleito como objeto de estudo e avaliado sob o viés da engenharia semiótica. Através da interface do aplicativo, analisou-se a qualidade da comunicação designer-usuário, tendo por objetivo verificar não apenas a eficiência da assistência virtual oferecida pelo sistema, mas também a autonomia do usuário e a flexibilidade do aplicativo diante de suas necessidades. / [en] Many modern systems and applications are capable of analising the contexts of use in real time, identifying key information to anticipate upcoming actions and optimize their interfaces. Those systems that work in a contextual manner and, usually, in a proactive way, belong to the Context Aware Computing area. The Google App for Android and iOS devices has a virtual assistant service that collects data obtained from different sources associated to the user account and links them to data from the user device. The assistant can identify habits, anticipate probable needs and offer information cards even before the user asks for them. Being part of the Context Aware Computing field, the Google App was elected as study object and was evaluated under the Semiotics Engineering bias. From the application s interface, the quality of the user-designer communication was analysed so, not only the virtual assistant efficiency could be evaluated, but also the user autonomy and the application flexibility according to his needs.