679 research outputs found

    Exchange market pressure and the credibility of Macau's currency Board

    Get PDF
    In this study, we assess the credibility of the currency board arrangement (CBA) of the Macau Special Administrative Region by studying the relationship between exchange market pressure (EMP) and the anchors of a rule-based CBA, namely, interest rate arbitrage, exchange rate arbitrage and economic discipline. A pure CBA signals its credibility by allowing the first two anchors to function automatically and by pursuing sound fiscal policies. The analysis’ results suggest that Macau’s CBA has been characterised by a state of low volatility since late 1992, with the brief exception of the East Asian financial crisis period. The paper’s main finding is that fiscal fundamentals seem to have a more pronounced role in reducing EMP’s variability during periods of low volatility whilst interest rate arbitrage is more important in periods of high volatility. We conclude that Macau’s CBA is credible at present as reflected in the low frequency of observed EMP, in the narrowing of Macau’s interest rate differential vis-à-vis U.S. interest rates and in Macau’s substantial fiscal reserves.

    Adaptive deblocking filter for transform domain Wyner-Ziv video coding

    Get PDF
    Wyner-Ziv (WZ) video coding is a particular case of distributed video coding, the recent video coding paradigm based on the Slepian-Wolf and Wyner-Ziv theorems that exploits the source correlation at the decoder and not at the encoder as in predictive video coding. Although many improvements have been done over the last years, the performance of the state-of-the-art WZ video codecs still did not reach the performance of state-of-the-art predictive video codecs, especially for high and complex motion video content. This is also true in terms of subjective image quality mainly because of a considerable amount of blocking artefacts present in the decoded WZ video frames. This paper proposes an adaptive deblocking filter to improve both the subjective and objective qualities of the WZ frames in a transform domain WZ video codec. The proposed filter is an adaptation of the advanced deblocking filter defined in the H.264/AVC (advanced video coding) standard to a WZ video codec. The results obtained confirm the subjective quality improvement and objective quality gains that can go up to 0.63 dB in the overall for sequences with high motion content when large group of pictures are used

    Metodologias participativas: Os media e a educação

    Get PDF

    Statistical motion learning for improved transform domain Wyner-Ziv video coding

    Get PDF
    Wyner - Ziv (WZ) video coding is a particular case of distributed video coding (DVC), the recent video coding paradigm based on the Slepian - Wolf and Wyner - Ziv theorems which exploits the source temporal correlation at the decoder and not at the encoder as in predictive video coding. Although some progress has been made in the last years, WZ video coding is still far from the compression performance of predictive video coding, especially for high and complex motion contents. The WZ video codec adopted in this study is based on a transform domain WZ video coding architecture with feedback channel-driven rate control, whose modules have been improved with some recent coding tools. This study proposes a novel motion learning approach to successively improve the rate-distortion (RD) performance of the WZ video codec as the decoding proceeds, making use of the already decoded transform bands to improve the decoding process for the remaining transform bands. The results obtained reveal gains up to 2.3 dB in the RD curves against the performance for the same codec without the proposed motion learning approach for high motion sequences and long group of pictures (GOP) sizes

    Distributed video coding with multiple side information

    Get PDF

    Avaliação da segurança de cobertura tradicional de madeira sujeita a degradação biológica

    Get PDF
    O presente trabalho propĂ”e-se apresentar a modelação probabilĂ­stica de uma estrutura-tipo de uma cobertura tradicional de madeira, sendo tomadas como variĂĄveis aleatĂłrias as dimensĂ”es geomĂ©tricas das secçÔes transversais, as propriedades mecĂąnicas da madeira e as acçÔes aplicadas Ă  estrutura, dando especial ĂȘnfase ao vento e neve. Depois de estabelecido o Ă­ndice de fiabilidade ÎČ para uma situação de nĂŁo degradação, serĂĄ avaliada a sua variação em função da evolução da degradação biolĂłgica provocada por fungos, modelada probabilisticamente como uma variação de secção transversal

    In situ measured cross section geometry of old timber structures and its influence on structural safety

    Get PDF
    Old timber structures may show significant variation in the cross section geometry along the same element, as a result of both construction methods and deterioration. As consequence, the definition of the geometric parameters in situ may be both time consuming and costly. This work presents the results of inspections carried out in different timber structures. Based on the obtained results, different simplified geometric models are proposed in order to efficiently model the geometry variations found. Probabilistic modelling techniques are also used to define safety parameters of existing timber structures, when subjected to dead and live loads, namely self-weight and wind actions. The parameters of the models have been defined as probabilistic variables, and safety of a selected case study was assessed using the Monte Carlo simulation technique. Assuming a target reliability index, a model was defined for both the residual cross section and the time dependent deterioration evolution. As a consequence, it was possible to compute probabilities of failure and reliability indices, as well as, time evolution deterioration curves for this structure. The results obtained provide a proposal for definition of the cross section geometric parameters of existing timber structures with different levels of decay, using a simplified probabilistic geometry model and considering a remaining capacity factor for the decayed areas. This model can be used for assessing the safety of the structure at present and for predicting future performance.Fundação para a CiĂȘncia e a Tecnologia (FCT

    Rice quality profiling to classify germplasm in breeding programs

    Get PDF
    The objective of this work was to define a quality space for assessing rice varieties. Eleven long grain varieties, seven commercial and four new advanced lines were assessed to obtain complete quality profile considering appearance, physicochemical parameters, water absorption behaviour, pasting profile and textural attributes. Commercial varieties were chosen to provide the widest variation in properties, applying the variability analysis concepts of the Taguchi method, including Japonicas, Indicas, hybrids and aromatics. Quality parameters were measured in five different dimensions of quality space (totalling 50). Variable reduction techniques were applied to chose 3 parameters in each dimension (totalling 15 quality indicators) that would describe the whole space with greatest orthogonality, accuracy and yet explaining a significant proportion of the whole variance of data. The analysis of the quality space thus defined and similarities between varieties is illustrated with the conclusion of how the 4 new advanced lines perform in terms of quality behaviour, where it is concluded that one of them is very promising as an improvement over European (Indica) towards the behaviour of a pure Guyana (Indica), whereas 3 others have significant shortcomings in various aspects of the quality space compared to all others, albeit their greater closeness to Japonicas

    Immunological Reconstitution Inflammatory Syndrome and Thrombotic Microangiopathy: Severe Complications in a Child With Acquired Immunodeficiency Syndrome

    Get PDF
    Some patients with human immunodeficiency virus (HIV) infection deteriorate shortly after starting highly active antiretroviral therapy (HAART), the so-called immunological reconstitution inflammatory syndrome (IRIS).1 Although having a spontaneous resolution in many instances, it can be fatal.1 Worse prognosis is seen in younger children, severe immunosuppression and central nervous system IRIS, or infections with specific agents, namely, Criptococcus.2 Hemophagocytic lymphohistiocytosis (HLH) has also been described in children with HIV infection, in the context of an immunological system dysregulation.3 Thrombotic microangiopathy (TMA) became rare with the introduction of HAART, being mostly associated with advanced disease.4 HIV-associated TMA has specific clinical aspects as well as a worse prognosis than idiopathic or congenital TMA.4-9 The authors present the case of a 10-month-old boy with advanced HIV infection who developed IRIS complicated with HLH and TMA during the course of his treatment.info:eu-repo/semantics/publishedVersio
    • 

    corecore