901 resultados para contraire trading
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The Pharma(ceuticals) industry is at a cross-roads. There are growing concerns that illegitimate products are penetrating the supply chain. There are proposals in many countries to apply RFID and other traceability technologies to solve this problem. However there are several trade-offs and one of the most crucial is between data visibility and confidentiality. In this paper, we use the TrakChain assessment framework tools to study the US Pharma supply chain and to compare candidate solutions to achieve traceability data security: Point-of-Dispense Authentication, Network-based electronic Pedigree, and Document-based electronic Pedigree. We also propose extensions to a supply chain authorization language that is able to capture expressive data sharing conditions considered necessary by the industry's trading partners. © 2013 IEEE.
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This paper presents a 2GS/s 10-bit CMOS digital-to-analog converter (DAC). This DAC consists of a unit current-cell matrix for 6MSBs and another unit current-cell matrix for 4LSBs, trading off between the precision and size of the chip. The Current Mode Logic (CML) is used to ensure high speed, and a double Centro-symmetric current matrix is designed by the Q(2) random walk strategy in order to ensure the linearity of the DAC. The DAC occupies 2.2 x 2.2 mm2 of die area, and consumes 790mw at a single 3.3V power supply.
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The proposed DAC consists of a unit current-cell matrix for 8MSBs and a binary-weighted array for 4LSBs, trading-off between the precision, speed, and size of the chip. In order to ensure the linearity of the DAC, a double Centro symmetric current matrix is designed by the Q2 random walk strategy. To achieve better dynamic performance, a latch is added in front of the current switch to change the input signal, such as its optimal cross-point and voltage level. For a 12bit resolution,the converter reaches an update rate of 300MHz.
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本文依据分布计算环境(DCE)中所提供的目录服务并结合开放分布处理(ODP)所提供的交易服务(TradingServices),提出了实现分布计算环境中对象互操作的联邦交易模型。给出了该交易模型在DCE中的实现结构模型。
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In this paper we present a federated trading model for the trading services of ODP, A federation constract is used to document the agreement between two federating traders. The federation constract consists of import constract and export constract. We discuss the constituent of the model based on the five viewpoints of ODP.
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O carvão e outros combustíveis fósseis, continuarão a ser, por décadas, a principal matéria-prima energética para as Centrais Térmicas, não obstante os esforços para, dentro do possível, substituir os combustíveis fósseis por fontes de energia renovável.Tal como está, hoje, bem documentado, a produção de gases com efeito estufa (GEE), designadamente CO2, resulta da combustão dos ditos combustíveis fósseis, sendo que se espera ser possível mitigar substancialmente a emissão de tais gases com a aplicação das chamadas Tecnologias Limpas do Carvão.Há, pois, necessidade de promover o abatimento do CO2 através de Tecnologias de Emissão Zero ou Tecnologias Livres de Carbono, incluindo designadamente a Captura, o Transporte e a Sequestração geológica de CO2 correspondentes ao que é costume designar por Tecnologias CAC (Captação e Armazenamento de Carbono). De facto, tais tecnologias e, designadamente, o armazenamento geológico de CO2 são as únicas que, no estado actual do conhecimento, são capazes de permitir que se cumpram as metas do ambicioso programa da EU para a energia e o ambiente conhecido por “20 20 para 2020” em conjugação com os aspectos económicos das directivas relativas ao Comércio Europeu de Licenças de Emissão – CELE (Directivas 2003/87/EC, 2004/101/EC e 2009/29/EC).A importância do tema está, aliás, bem demonstrada com o facto da Comissão Europeia ter formalmente admitido que as metas supracitadas serão impossíveis de atingir sem Sequestração Geológica de CO2. Esta é, pois, uma das razões de ter sido recentemente publicada a Directiva Europeia 2009/31/EC de 23 de Abril de 2009 expressamente dedicada ao tema do Armazenamento Geológico de CO2.Ora, a questão do armazenamento geológico de CO2 implica, para além das Tecnologias CAC acima mencionadas e da sua viabilização em termos tanto técnicos como económicos, ou seja, neste último aspecto, competitiva com o sistema CELE, também o conhecimento, da percepção pública sobre o assunto. Isto é, a praticabilidade das Tecnologias CAC implica que se conheça a opinião pública sobre o tema e, naturalmente, que face a esta realidade se prestem os esclarecimentos necessários como, aliás, é reconhecido na própria Directiva Europeia 2009/31/EC.Dado que a Fundação Fernando Pessoa / Universidade Fernando Pessoa através do seu Centro de Investigação em Alterações Globais, Energia, Ambiente e Bioengenharia – CIAGEB tem ultimado um Projecto de Engenharia relativo à Sequestração Geológica de CO2 nos Carvões (Metantracites) da Bacia Carbonífera do Douro – o Projecto COSEQ, preocupou-se naturalmente, desde o início, com o lançamento de inquéritos de percepção da opinião pública sobre o assunto.Tal implicou, nesta fase, a tradução para português e o lançamento do inquérito europeu ACCSEPT que não tinha sido ainda formalmente lançado de forma generalizada entre nós. Antes, porém, de lançar publicamente tal inquérito – o que está actualmente já em curso – resolveu-se testar o método de lançamento, a recolha de dados e o seu tratamento com uma amostra correspondente ao que se designou por Comunidade Fernando Pessoa, i.e. o conjunto de docentes, discentes, funcionários e outras pessoas relacionadas com a Universidade Fernando Pessoa (cerca de 5000 individualidades).Este trabalho diz, precisamente, respeito à preparação, lançamento e análise dos resultados do dito inquérito Europeu ACCSEPT a nível da Comunidade Fernando Pessoa. Foram recebidas 525 respostas representando 10,5% da amostra. A análise de resultados foi sistematicamente comparada com os obtidos nos outros países europeus, através do projecto ACCSEPT e, bem assim, com os resultados obtidos num inquérito homólogo lançado no Brasil. The use of coal, and other fossil fuels, will remain for decades as the main source of energy for power generation, despite the important efforts made to replace, as far as possible, fossil fuels with renewable power sources.As is well documented, the production of Greenhouse Gases (GHG), mainly CO2, arises primarily from the combustion of fossil fuels. The increasing application of Clean Coal Technologies-CCTs, is expected to mitigate substantially against the emission of such gases.There is consequently a need to promote the CO2 abatement through Zero Emission (Carbon Free) Technologies - ZETs, which includes CO2 capture, transport and geological storage, i.e. the so-called CCS (Carbon, Capture and Storage) technologies. In fact, these technologies are the only ones that are presently able to conform to the ambitious EU targets set out under the “20 20 by 2020” EU energy and environment programme, jointly with the economic aspects of the EU Directives 2003/87/EC, 2004/101/EC and 2009/29/EC concerned with the Greenhouse Gas Emissions Allowance Trading Scheme – ETS scheme. The European Commission formal admission that the referred targets will be impossible to reach without the implementation and contribution of geological storage clearly demonstrate the importance of this particular issue, and for this reason the EC Directive 2009/31/EC of April 23, 2009 on Geological Storage of CO2 was recently published.In considering the technical and economical viabilities of CCS technologies, the latter in competition with the ETS scheme, it is believed that public perception will dictate the success of the development and implementation of CO2 geological storage at a large industrial level. This means that, in order to successfully implement CCS technologies, not only must public opinion be taken into consideration but objective information must also be provided to the public in order to raise subject awareness, as recognized in the referred Directive 2009/31/EC.In this context, the Fernando Pessoa Foundation / University Fernando Pessoa, through its CIAGEB (Global Change, Energy, Environment and Bioengineering) RDID&D Unit, is the sponsor of an Engineering Project for the Geological Sequestration of CO2 in Douro Coalfield Meta-anthracites - the COSEQ Project, and is therefore also engaged in public perception surveys with regards to CCS technologies.At this stage, the original European ACCSEPT inquiry was translated to Portuguese and submitted only to the “Fernando Pessoa Community” - comprising university lecturers, students, other employees, as well as, former students and persons that have a professional or academic relationship with the university (c. 5000 individuals). The results obtained from this first inquiry will be used to improve the survey informatics system in terms of communication, database, and data treatment prior to resubmission of the inquiry to the Portuguese public at large.The present publication summarizes the process and the results obtained from the ACCSEPT survey distributed to the “Fernando Pessoa Community”. 525 replies, representing 10.5% of the sample, have been received and analysed. The assessment of the results was systematically compared with those obtained from other European Countries, as reported by the ACCSEPT inquiry, as well as with those from an identical inquiry launched in Brazil.
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Dissertação de Mestrado apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Psicologia, especialização em Psicologia Clínica e da Saúde.
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The increased diversity of Internet application requirements has spurred recent interests in transport protocols with flexible transmission controls. In window-based congestion control schemes, increase rules determine how to probe available bandwidth, whereas decrease rules determine how to back off when losses due to congestion are detected. The parameterization of these control rules is done so as to ensure that the resulting protocol is TCP-friendly in terms of the relationship between throughput and loss rate. In this paper, we define a new spectrum of window-based congestion control algorithms that are TCP-friendly as well as TCP-compatible under RED. Contrary to previous memory-less controls, our algorithms utilize history information in their control rules. Our proposed algorithms have two salient features: (1) They enable a wider region of TCP-friendliness, and thus more flexibility in trading off among smoothness, aggressiveness, and responsiveness; and (2) they ensure a faster convergence to fairness under a wide range of system conditions. We demonstrate analytically and through extensive ns simulations the steady-state and transient behaviors of several instances of this new spectrum of algorithms. In particular, SIMD is one instance in which the congestion window is increased super-linearly with time since the detection of the last loss. Compared to recently proposed TCP-friendly AIMD and binomial algorithms, we demonstrate the superiority of SIMD in: (1) adapting to sudden increases in available bandwidth, while maintaining competitive smoothness and responsiveness; and (2) rapidly converging to fairness and efficiency.
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The advent of virtualization and cloud computing technologies necessitates the development of effective mechanisms for the estimation and reservation of resources needed by content providers to deliver large numbers of video-on-demand (VOD) streams through the cloud. Unfortunately, capacity planning for the QoS-constrained delivery of a large number of VOD streams is inherently difficult as VBR encoding schemes exhibit significant bandwidth variability. In this paper, we present a novel resource management scheme to make such allocation decisions using a mixture of per-stream reservations and an aggregate reservation, shared across all streams to accommodate peak demands. The shared reservation provides capacity slack that enables statistical multiplexing of peak rates, while assuring analytically bounded frame-drop probabilities, which can be adjusted by trading off buffer space (and consequently delay) and bandwidth. Our two-tiered bandwidth allocation scheme enables the delivery of any set of streams with less bandwidth (or equivalently with higher link utilization) than state-of-the-art deterministic smoothing approaches. The algorithm underlying our proposed frame-work uses three per-stream parameters and is linear in the number of servers, making it particularly well suited for use in an on-line setting. We present results from extensive trace-driven simulations, which confirm the efficiency of our scheme especially for small buffer sizes and delay bounds, and which underscore the significant realizable bandwidth savings, typically yielding losses that are an order of magnitude or more below our analytically derived bounds.
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Within a recently developed low-power ad hoc network system, we present a transport protocol (JTP) whose goal is to reduce power consumption without trading off delivery requirements of applications. JTP has the following features: it is lightweight whereby end-nodes control in-network actions by encoding delivery requirements in packet headers; JTP enables applications to specify a range of reliability requirements, thus allocating the right energy budget to packets; JTP minimizes feedback control traffic from the destination by varying its frequency based on delivery requirements and stability of the network; JTP minimizes energy consumption by implementing in-network caching and increasing the chances that data retransmission requests from destinations "hit" these caches, thus avoiding costly source retransmissions; and JTP fairly allocates bandwidth among flows by backing off the sending rate of a source to account for in-network retransmissions on its behalf. Analysis and extensive simulations demonstrate the energy gains of JTP over one-size-fits-all transport protocols.
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Investment funds provide a low cost method of sharing in the rewards from capitalism. Recently “alternative investments” such as hedge funds have grown rapidly and the trading strategies open to hedge funds are now becoming available to mutual funds and even to ordinary retail investors. In this paper we analyze problems in assessing fund performance and the prospects for investment fund sectors. Choosing genuine outperformers among top funds requires a careful assessment of non-normality, order statistics and the possibility of false discoveries. The risk adjusted performance of the average hedge fund over the last 10-15 is actually not that impressive, although the “top” funds do appear to have statistically significant positive alphas.
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Hitherto, the majority of studies which have included the discussion of Viking glass beads have mainly focused on the assemblages from individual sites, with limited use of known parallels. Exceptions to this include recent publications regarding the Icelandic material and Callmer’s 1977 catalogue of the finds from mainland Scandinavia, now over thirty years old. Analysis of these finds from Ireland was, for the most part, non-existent. The aim of this research is to address this lack of analysis within Ireland, while incorporating the wider context of the beads within the Viking North Atlantic. The research thus examines the use of glass beads of diagnostically Scandinavian manufacture and import found in Ireland, particularly in relation to their context and distribution. The history of research from Ireland as well as from across the Viking world is considered and explored throughout the thesis, with critique of methods and discussions used. Focussed analysis of both published and unpublished material detailing artefacts from Scandinavia (especially Vestfold), Britain, Iceland, the Faroe Islands and L’Anse aux Meadows is presented within the thesis in order to provide the greater picture for the core section of the thesis, the glass beads found in Ireland. Three appendices are included within Volume 2, databases of the glass beads under discussion from Ireland, the Vestfold region graves in Norway and the topsoil finds from the Kaupang trading place, also located within Vestfold. These appendices therefore represent the first-hand analysis of glass beads by the author. In total, this research represents the most up-to-date analysis of Viking glass beads from Ireland and presents a new look at the patterns of use, trade and interpersonal contact that affected the everyday lives of individuals living within Viking Age Ireland.
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This dissertation applies a variety of quantitative methods to electricity and carbon market data, utility company accounts data, capital and operating costs to analyse some of the challenges associated with investment in energy assets. In particular, three distinct research topics are analysed within this general theme: the efficiency of interconnector trading, the optimal sizing of intermittent wind facilities and the impact of carbon pricing on the cost of capital for investors are researched in successive sections.
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Wind power generation differs from conventional thermal generation due to the stochastic nature of wind. Thus wind power forecasting plays a key role in dealing with the challenges of balancing supply and demand in any electricity system, given the uncertainty associated with the wind farm power output. Accurate wind power forecasting reduces the need for additional balancing energy and reserve power to integrate wind power. Wind power forecasting tools enable better dispatch, scheduling and unit commitment of thermal generators, hydro plant and energy storage plant and more competitive market trading as wind power ramps up and down on the grid. This paper presents an in-depth review of the current methods and advances in wind power forecasting and prediction. Firstly, numerical wind prediction methods from global to local scales, ensemble forecasting, upscaling and downscaling processes are discussed. Next the statistical and machine learning approach methods are detailed. Then the techniques used for benchmarking and uncertainty analysis of forecasts are overviewed, and the performance of various approaches over different forecast time horizons is examined. Finally, current research activities, challenges and potential future developments are appraised.
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Vietnam launched its first-ever stock market, named as Ho Chi Minh City Securities Trading Center (HSTC) on July 20, 2000. This is one of pioneering works on HSTC, which finds empirical evidences for the following: Anomalies of the HSTC stock returns through clusters of limit-hits, limit-hit sequences; Strong herd effect toward extreme positive returns of the market portfolio;The specification of ARMA-GARCH helps capture fairly well issues such as serial correlations and fat-tailed for the stabilized period. By using further information and policy dummy variables, it is justifiable that policy decisions on technicalities of trading can have influential impacts on the move of risk level, through conditional variance behaviors of HSTC stock returns. Policies on trading and disclosure practices have had profound impacts on Vietnam Stock Market (VSM). The over-using of policy tools can harm the market and investing mentality. Price limits become increasingly irrelevant and prevent the market from self-adjusting to equilibrium. These results on VSM have not been reported before in the literature on Vietnam’s financial markets. Given the policy implications, we suggest that the Vietnamese authorities re-think the use of price limit and give more freedom to market participants.