A novel latent factor model for recommender system

Matrix factorization (MF) has evolved as one of the better practice to handle sparse data in field of recommender systems. Funk singular value decomposition (SVD) is a variant of MF that exists as state-of-the-art method that enabled winning the Netflix prize competition. The method is widely used with modifications in present day research in field of recommender systems. With the potential of data points to grow at very high velocity, it is prudent to devise newer methods that can handle such data accurately as well as efficiently than Funk-SVD in the context of recommender system. In view of the growing data points, I propose a latent factor model that caters to both accuracy and efficiency by reducing the number of latent features of either users or items making it less complex than Funk-SVD, where latent features of both users and items are equal and often larger. A comprehensive empirical evaluation of accuracy on two publicly available, amazon and ml-100 k datasets reveals the comparable accuracy and lesser complexity of proposed methods than Funk-SVD.

Internet das Coisas aplicada a negócios – Um estudo bibliométrico

The Internet of Things is a technological innovation, based on artifacts and consolidated concepts like Internet and Smart Objects. Its growing business application of Internet of Things makes necessary to evaluate the strategy, benefits and challenges of this technology application. The main objective of this paper is to present the definition of Internet of Things, based on the most cited articles and as a secondary objective, present publication statistics classified by year and related terms, like ubiquitous computation. One of the conclusions is that papers related to business represent only 5% of all the papers analyzed by this research, considering just the papers published on journals. It shows that there is a great field to research on Business Administration.

Entrepreneurship in project management systems: proposal of a model and preliminary empirical evidence

This study analyzes the manifestation of the dimensions of Entrepreneurial Orientation (EO) and Project Management Systems (PMS). We used a qualitative approach to conduct exploratory research through a study in literature and a pilot case in a software company. Data was collected from semi structured interviews, documents, and records on file, then triangulated and treated with content analysis. The model proposed for the relationship between the types of PMS (ad hoc, Classic PM, innovation, entrepreneurship/intrapreneurship) and the dimensions of EO (innovativeness, risk-taking, proactiveness, competitive aggressiveness, and autonomy), was partially corroborated by empirical studies. New studies are suggested to validate the applicability and setup of the model.

Favorability conditions in the adoption of agile method practices for software development in a public banking

The main purpose of this paper is to propose and test a model to assess the degree of conditions favorability in the adoption of agile methods to develop software where traditional methods predominate. In order to achieve this aim, a survey was applied on software developers of a Brazilian public retail bank. Two different statistical techniques were used in order to assess the quantitative data from the closed questions in the survey. The first, exploratory factorial analysis validated the structure of perspectives related to the agile model of the proposed assessment. The second, frequency distribution analysis to categorize the answers. Qualitative data from the survey opened question were analyzed with the technique of qualitative thematic content analysis. As a result, the paper proposes a model to assess the degree of favorability conditions in the adoption of Agile practices within the context of the proposed study.

What Influences Information Security Behavior? A Study with Brazilian Users

The popularization of software to mitigate Information Security threats can produce an exaggerated notion about its full effectiveness in the elimination of any threat. This situation can result reckless users behavior, increasing vulnerability. Based on behavioral theories, a theoretical model and hypotheses were developed to understand the extent to which human perception of threat, stress, control and disgruntlement can induce responsible behavior. A self-administered questionnaire was created and validated. The data were collected in Brazil, and complementary results regarding similar studies conducted in USA were found. The results show that there is influence of information security orientations provided by organizations in the perception about severity of the threat. The relationship between threat, effort, control and disgruntlement, and the responsible behavior towards information security was verified through linear regression. The contributions also involve relatively new concepts in the field and a new research instrument.

Using Research Methods in Human Computer Interaction to Design Technology for Resilience

Research in human computer interaction (HCI) covers both technological and human behavioural concerns. As a consequence, the contributions made in HCI research tend to be aware to either engineering or the social sciences. In HCI the purpose of practical research contributions is to reveal unknown insights about human behaviour and its relationship to technology. Practical research methods normally used in HCI include formal experiments, field experiments, field studies, interviews, focus groups, surveys, usability tests, case studies, diary studies, ethnography, contextual inquiry, experience sampling, and automated data collection. In this paper, we report on our experience using the evaluation methods focus groups, surveys and interviews and how we adopted these methods to develop artefacts: either interface’s design or information and technological systems. Four projects are examples of the different methods application to gather information about user’s wants, habits, practices, concerns and preferences. The goal was to build an understanding of the attitudes and satisfaction of the people who might interact with a technological artefact or information system. Conversely, we intended to design for information systems and technological applications, to promote resilience in organisations (a set of routines that allow to recover from obstacles) and user’s experiences. Organisations can here also be viewed within a system approach, which means that the system perturbations even failures could be characterized and improved. The term resilience has been applied to everything from the real estate, to the economy, sports, events, business, psychology, and more. In this study, we highlight that resilience is also made up of a number of different skills and abilities (self-awareness, creating meaning from other experiences, self-efficacy, optimism, and building strong relationships) that are a few foundational ingredients, which people should use along with the process of enhancing an organisation’s resilience. Resilience enhances knowledge of resources available to people confronting existing problems.

A segurança dos sistemas de informação e o comportamento dos usuários

Numa sociedade cada vez mais global e em constante mutação, onde as organizações necessitam ter sempre disponível a informação necessária e útil para desenvolver, de uma forma rápida e eficaz, as suas atividades no dia-a-dia, garantir a segurança da informação é um fator fundamental para sustentar a sua continuidade e sucesso.Neste estudo procura-se saber em que medida os comportamentos e as atitudes dos usuários dos sistemas de informação constituem um risco ou uma proteção para a segurança destes sistemas. Para alcançar este objetivo foi primeiramente realizada uma revisão bibliográfica baseada em fontes secundárias, que permitiu desenvolver o questionário para coleta de dados; seguidamente, e usando um questionário online, foram recolhidas respostas de 780 sujeitos, que maioritariamente trabalham em Portugal. Os dados obtidos foram objeto de um tratamento estatístico simples, nomeadamente análise de frequências e médias. A principal conclusão do estudo revela que os usuários, de uma forma geral, constituem uma proteção para a segurança dos sistemas de informação nas organizações.

The Museum of the Void

Reflexão sobre as possbilidades de significação e intervenção sobre os enormes espaços vazios gerados pela desactivção de sistemas de silagem de cereais. O potencial programático que o próprio espaço vazio pode, em si, encerrar, é ponto de partida para considerações arquitectónicas, onde se convoca também o valor da proposta projectual como instrumento de ensaio.Trata-se de um texto que integra o catálogo da Exposição homónima, a partir de exploração projectual em domínio académico avançado (Mestrado Integrado).

Biosurfactant-producing bacteria from an oil-contaminated mangrove.

2008

Composição físico-química de vinhos tropicais elaborados no Nordeste do Brasil.

2011