A Comparative Study Between U.S. and Brazilian Acquisition Regulations and Practices

The researcher undergoes a tripartite comparative analysis approach using: (1) Brazilian Acquisition Law, (2) US Federal Acquisition Regulation and (3) Selected Articles from the European Journal of Purchasing and Supply Management (1996-2010). Specifically, the primary research question is: How does the Brazilian Law 8666/93 compare to the American Federal Acquisition Regulation (FAR/84)? Therefore, an in-depth assessment and analysis of the procurement systems of the United States and Brazil is executed in order to determine the different perspectives and policies adopted by these countries; and how differently each Government perceive the purchase function. An extensive literature review using selected articles from the European Journal of Purchasing and Supply Management (1996-2010) enabled the generation of 22 potential topics for comparative purposes. This research is qualitative in nature and two methods were utilized: Coding techniques and CRA (Center Resonance Analysis). A complete coding structure was developed using the Brazilian Acquisition Law as the primary basis, and two main coding structure parts were selected in an endeavor to answer the research questions. The set of analyses were facilitated through the use of the Crawdad Software, which applies text analysis techniques by representing the text as a network of essential linked concepts. Several lessons learned were collected that can be ultimately incorporated on the purchasing practices of the Brazilian acquisition system

Power Quality of Renewable Energy Source Systems: A New Paradigm of Electrical Grids

The power quality delivered by the distribution companies to consumers has always been a relevant issue, especially to industrial consumers, where power quality is directly related to productivity. However, until a few years ago, power quality was mostly synonymous with continuity of service, and the main concern was the minimization of power interruptions. Since the last decade of the twentieth century, power quality has become a strategic issue for all sectors involved in this market, from distribution companies to consumers, with a particular emphasis on industrial consumers as well as equipment manufacturers. The concept of power quality involves a wide range of electromagnetic phenomena that can occur in the power grid. Such changes may occur in different parts of the electrical power system, at customer facilities, or in the distribution network. In recent years, the electric power market has undergone huge transformations, electricity production has become decentralized, and consumers (who can now also be producers) have the opportunity to choose their supplier. The integration of renewable-based microgeneration systems into distribution grids has brought various disturbances to the grid (harmonics, voltage unbalance, voltage fluctuations, frequency deviations, etc.), leading to increasingly degraded power quality. This Special Issue focuses on the analysis of the consequences that renewables-based microgeneration systems have on power networks by finding new solutions for networks management (network optimization models, efficiency, and losses), integrating consumers and micro-producers in order to keep quality parameters at high levels. In this Special Issue, we can see that the interdisciplinarity of these issues is very present among researchers and scholars, who are well aware of the importance and impact that the new paradigm of network management brings in various domains, reflecting on the quality of the contributions submitted. Accordingly, the papers selected for publication cover a wide range of application topics, including electrical mobility, energy storage systems, facility management and control, impact analysis of different types of renewable energy sources, with focus on wind and solar generation, in both low-voltage (LV) and medium-voltage (MV) networks.info:eu-repo/semantics/publishedVersio

Vitis: A Gossip-based Hybrid Overlay for Internet-scale Publish/Subscribe

Peer-to-peer overlay networks are attractive solutions for building Internet-scale publish/subscribe systems. However, scalability comes with a cost: a message published on a certain topic often needs to traverse a large number of uninterested (unsubscribed) nodes before reaching all its subscribers. This might sharply increase resource consumption for such relay nodes (in terms of bandwidth transmission cost, CPU, etc) and could ultimately lead to rapid deterioration of the system’s performance once the relay nodes start dropping the messages or choose to permanently abandon the system. In this paper, we introduce Vitis, a gossip-based publish/subscribe system that significantly decreases the number of relay messages, and scales to an unbounded number of nodes and topics. This is achieved by the novel approach of enabling rendezvous routing on unstructured overlays. We construct a hybrid system by injecting structure into an otherwise unstructured network. The resulting structure resembles a navigable small-world network, which spans along clusters of nodes that have similar subscriptions. The properties of such an overlay make it an ideal platform for efficient data dissemination in large-scale systems. We perform extensive simulations and evaluate Vitis by comparing its performance against two base-line publish/subscribe systems: one that is oblivious to node subscriptions, and another that exploits the subscription similarities. Our measurements show that Vitis significantly outperforms the base-line solutions on various subscription and churn scenarios, from both synthetic models and real-world traces

Coordination of European transnational research in organic food and farming

Research in organic food and farming is a fairly new, but rapidly ex-panding, discipline on the European research scene. One of the problems faced by the authorities seeking to initiate research programmes in organic food and farming is that the present research effort in Europe is caracterised by small research communities, which are often scattered and fragmented both geographically and institutionally. Therefore a gathering of the dispersed expertise to a critical mass in order to increase the competitive quality and relevance of the research as well as the dessemination and use of research is needed

How are topics born? Understanding the research dynamics preceding the emergence of new areas

The ability to promptly recognise new research trends is strategic for many stake- holders, including universities, institutional funding bodies, academic publishers and companies. While the literature describes several approaches which aim to identify the emergence of new research topics early in their lifecycle, these rely on the assumption that the topic in question is already associated with a number of publications and consistently referred to by a community of researchers. Hence, detecting the emergence of a new research area at an embryonic stage, i.e., before the topic has been consistently labelled by a community of researchers and associated with a number of publications, is still an open challenge. In this paper, we begin to address this challenge by performing a study of the dynamics preceding the creation of new topics. This study indicates that the emergence of a new topic is anticipated by a significant increase in the pace of collaboration between relevant research areas, which can be seen as the ‘parents’ of the new topic. These initial findings (i) confirm our hypothesis that it is possible in principle to detect the emergence of a new topic at the embryonic stage, (ii) provide new empirical evidence supporting relevant theories in Philosophy of Science, and also (iii) suggest that new topics tend to emerge in an environment in which weakly interconnected research areas begin to cross-fertilise

Crisis Communication Patterns in Social Media during Hurricane Sandy

Hurricane Sandy was one of the deadliest and costliest of hurricanes over the past few decades. Many states experienced significant power outage, however many people used social media to communicate while having limited or no access to traditional information sources. In this study, we explored the evolution of various communication patterns using machine learning techniques and determined user concerns that emerged over the course of Hurricane Sandy. The original data included ~52M tweets coming from ~13M users between October 14, 2012 and November 12, 2012. We run topic model on ~763K tweets from top 4,029 most frequent users who tweeted about Sandy at least 100 times. We identified 250 well-defined communication patterns based on perplexity. Conversations of most frequent and relevant users indicate the evolution of numerous storm-phase (warning, response, and recovery) specific topics. People were also concerned about storm location and time, media coverage, and activities of political leaders and celebrities. We also present each relevant keyword that contributed to one particular pattern of user concerns. Such keywords would be particularly meaningful in targeted information spreading and effective crisis communication in similar major disasters. Each of these words can also be helpful for efficient hash-tagging to reach target audience as needed via social media. The pattern recognition approach of this study can be used in identifying real time user needs in future crises

Coordination of European Transnational Research in Organic Farming Systems

Organic agriculture and food markets have grown considerably, and organic agriculture addresses important challenges of European agriculture, such as the sustainable production of high-quality food, reducing dependency on high energy inputs, improving environmental and nature conservation, climate change adaptation, animal welfare and rural livelihoods. Organic farming and food systems still have a huge potential for innovation and improved solutions. Research activities will be important for this