ESTG - Capítulos de livros
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- O direito natural e o regionalismoPublication . Abrunhosa, Ângelo
- Temporality in negotiations: a cultural perspectivePublication . Armagan, Sungu; Ferreira, Manuel Portugal; Bonner, Bryan L.; Okhuysen, A.This paper discusses national differences in the interpretation of time in mixed motive decision contexts, such as negotiation. Specifically, we consider how members of different national cultures (Portugal, Turkey, and the United States) experience temporality in these situations. We argue that cultural temporality such as polychronicity, future orientation, and uncertainty avoidance form part of a broader national environment. The national environment is also expressed in national stability factors such as legal systems, family ties, and homogeneity of populations. We propose that temporality and stability aspects of national environment determine negotiation paradigms, which subsequently influence temporality in negotiations. We conclude by suggesting that inclusion of complex and interdependent national environment factors in the study of negotiation has the potential to substantially advance our understanding of mixed motive decision situations.
- A new perspective on parenting spin-offs for cluster formationPublication . Ferreira, Manuel Portugal; Hesterly, William; Tavares, Ana Teresa
- Evolution of Industry Clusters through Spin-offs and the Role of Flagship FirmsPublication . Ferreira, Manuel Portugal; Tavares, Ana Teresa; Hesterly, William
- Building and leveraging knowledge capabilities through cross-border acquisitionsPublication . Ferreira, Manuel Portugal
- Design of Radio-Frequency Integrated CMOS Discrete Tuning Varactors Using the Particle Swarm Optimization AlgorithmPublication . Pires, E. J. Solteiro; Mendes, Luís; Oliveira, P. B. de Moura; Machado, J. A. Tenreiro; Vaz, João C.; Rosário, Maria J.This paper presents an automated design procedure of radio- frequency integrated CMOS discrete tuning varactors (RFDTVs). This new method use the maximin and the particle swarm optimization (PSO) algorithms to promote well distributed non-dominated fronts in the parameters space when a single-objective function is optimized. The fitness function used in the search tool is proportional to the RFDTV quality factor. The outcome of the automated design method comprises a set of RFDTV circuits, all having the same maximum performance. Each solution, which corresponds to one RFDTV circuit, is defined by the number of cells and by the circuit components values. This approach allows the designer to choose among several possible circuits the one that is easier to implement in a given CMOS process. To validate the effectiveness of the synthesis procedure proposed in this paper (PSO-method) comparisons with a design method based on genetic algorithms (GA-method) are presented. A 0.18 μm CMOS radio-frequency binary-weighted differential switched capacitor array (RFDSCA) was designed and implemented (the RFDSCA is one of the possible topologies of the RFDTVs). The results show that both design methods are in very good agreement. However, the PSO technique outperforms the GA-method in the design procedure run time taken to accomplish the same performance results.
- The Radio Network Design Optimization ProblemPublication . Mendes, Silvio; Gómez-Pulido, Juan A.; Vega-Rodríguez, Miguel A.; Sánchez-Pérez, Juan M.; Sáez, Yago; Isasi, PedroThe fast growth and merging of communication infrastructures and services turned the planning and design of wireless networks into a very complex subject. The Radio Network Design (RND) is a NP-hard optimization problem which consists on the maximization of the coverage of a given area while minimizing the base station (BS) deployment. Solving such problems resourcefully is relevant for many fields of application and has direct impact in engineering, scientific and industrial areas. Its significance is growing due to cost dropping or profit increase allowance and can additionally be applied to several different business targets. Numerous works can be found in the literature dealing with the RND problem, although they all suffer from the same shortfall: a non-comparable efficiency. Therefore, the aim of this work is threefold: first, to offer a reliable RND benchmark reference covering a wide algorithmic spectrum, second, to offer a grand insight of accurately comparisons of efficiency, reliability and swiftness of the different employed algorithmic models and third, to disclose reproducibility details of the implemented models, including simulations of a hardware co-processing accelerator.
- Video Transcoding TechniquesPublication . Moiron, Sandro; Ghanbari, Mohammed; Assunção, Pedro; Faria, SergioThis chapter addresses the most recent advances in video transcoding and processing architectures for multimedia content adaptation. The first section provides an overview of the state of the art, where video transcoding is described as a key solution to enable seamless interoperability across diverse multimedia communication systems and services. Then, a detailed analysis of relevant transcoding functions is presented, addressing their implementation, coding performance and computational complexity. The different processing architectures that can be used for video transcoding are also described, according to their respective functionalities and application scenarios. Other solutions capable of providing adaptation of coded video to heterogeneous environments, such as scalable video coding and multiple description video coding are also discussed and their main advantages and disadvantages are highlighted. A case study is also presented to illustrate the need and effectiveness of video transcoding in modern applications.
- Evaluating Hybrid Ensembles for Intelligent Decision Support for Intensive CarePublication . Gago, Pedro; Santos, Manuel FilipeThe huge amount of data available in an Intensive Care Unit (ICU) makes ICUs an attractive field for data analysis. However, effective decision support systems operating in such an environment should not only be accurate but also as autonomous as possible, being capable of maintaining good performance levels without human intervention. Moreover, the complexity of an ICU setting is such that available data only manages to cover a limited part of the feature space. Such characteristics led us to investigate the development of ensemble update techniques capable of improving the discriminative power of the ensemble. Our chosen technique is inspired by the Dynamic Weighted Majority algorithm, an algorithm initially developed for the concept drift problem. In this paper we will show that in the problem we are addressing, simple weight updates do not improve results, whereas an ensemble, where we allow not only weight updates, but also the creation and eliminations of models, significantly increases classification performance.
- Analysis of finite oscillating GIX/M(m)//N queueing systemsPublication . Ferreira, Fátima; Pacheco, António; Ribeiro, Helena; Ribeiro, Helena;In this work we investigate oscillating GIX/M(m)//N systems, which are queueing systems whose service mechanism reacts to the congestion of the system; namely, the service rates oscillate between two forms according to the evolution of the number of customers in the system. Resorting to Markov chain embedding, we address the time-dependent and limit analysis of the number of customers in the system at batch prearrivals and seen by customers at their arrival to the system. These results are then used to derive the continuous-time limit distribution of the number of customers in the system. In addition, we provide some numerical examples that illustrate our approach.