224 resultados para Optimal switch allocation
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In cloud computing, resource allocation and scheduling of multiple composite web services is an important and challenging problem. This is especially so in a hybrid cloud where there may be some low-cost resources available from private clouds and some high-cost resources from public clouds. Meeting this challenge involves two classical computational problems: one is assigning resources to each of the tasks in the composite web services; the other is scheduling the allocated resources when each resource may be used by multiple tasks at different points of time. In addition, Quality-of-Service (QoS) issues, such as execution time and running costs, must be considered in the resource allocation and scheduling problem. Here we present a Cooperative Coevolutionary Genetic Algorithm (CCGA) to solve the deadline-constrained resource allocation and scheduling problem for multiple composite web services. Experimental results show that our CCGA is both efficient and scalable.
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Background: Bioimpedance techniques provide a reliable method of assessing unilateral lymphedema in a clinical setting. Bioimpedance devices are traditionally used to assess body composition at a current frequency of 50 kHz. However, these devices are not transferable to the assessment of lymphedema, as the sensitivity of measuring the impedance of extracellular fluid is frequency dependent. It has previously been shown that the best frequency to detect extracellular fluid is 0 kHz (or DC). However, measurement at this frequency is not possible in practice due to the high skin impedance at DC, and an estimate is usually determined from low frequency measurements. This study investigated the efficacy of various low frequency ranges for the detection of lymphedema. Methods and Results: Limb impedance was measured at 256 frequencies between 3 kHz and 1000 kHz for a sample control population, arm lymphedema population, and leg lymphedema population. Limb impedance was measured using the ImpediMed SFB7 and ImpediMed L-Dex® U400 with equipotential electrode placement on the wrists and ankles. The contralateral limb impedance ratio for arms and legs was used to calculate a lymphedema index (L-Dex) at each measurement frequency. The standard deviation of the limb impedance ratio in a healthy control population has been shown to increase with frequency for both the arm and leg. Box and whisker plots of the spread of the control and lymphedema populations show that there exists good differentiation between the arm and leg L-Dex measured for lymphedema subjects and the arm and leg L-Dex measured for control subjects up to a frequency of about 30 kHz. Conclusions: It can be concluded that impedance measurements above a frequency of 30 kHz decrease sensitivity to extracellular fluid and are not reliable for early detection of lymphedema.
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Caveats as protection for unregistered interests - lapsing and non-lapsing caveats - caveator - use only in appropriate circumstances
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Power systems in many countries are stressed towards their stability limit. If these stable systems experience any unexpected serious contingencies, or disturbances, there is a significant risk of instability, which may lead to wide-spread blackout. Frequency is a reliable indicator for such instability condition exists on the power system; therefore under-frequency load shedding technique is used to stable the power system by curtail some load. In this paper, the SFR-UFLS model redeveloped to generate optimal load shedding method is that optimally shed load following one single particular contingency event. The proposed optimal load shedding scheme is then tested on the 39-bus New England test system to show the performance against random load shedding scheme.
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Distributed generators (DGs) are defined as generators that are connected to a distribution network. The direction of the power flow and short-circuit current in a network could be changed compared with one without DGs. The conventional protective relay scheme does not meet the requirement in this emerging situation. As the number and capacity of DGs in the distribution network increase, the problem of coordinating protective relays becomes more challenging. Given this background, the protective relay coordination problem in distribution systems is investigated, with directional overcurrent relays taken as an example, and formulated as a mixed integer nonlinear programming problem. A mathematical model describing this problem is first developed, and the well-developed differential evolution algorithm is then used to solve it. Finally, a sample system is used to demonstrate the feasiblity and efficiency of the developed method.
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Some uncertainties such as the stochastic input/output power of a plug-in electric vehicle due to its stochastic charging and discharging schedule, that of a wind unit and that of a photovoltaic generation source, volatile fuel prices and future uncertain load growth, all together could lead to some risks in determining the optimal siting and sizing of distributed generators (DGs) in distributed systems. Given this background, under the chance constrained programming (CCP) framework, a new method is presented to handle these uncertainties in the optimal sitting and sizing problem of DGs. First, a mathematical model of CCP is developed with the minimization of DGs investment cost, operational cost and maintenance cost as well as the network loss cost as the objective, security limitations as constraints, the sitting and sizing of DGs as optimization variables. Then, a Monte Carolo simulation embedded genetic algorithm approach is developed to solve the developed CCP model. Finally, the IEEE 37-node test feeder is employed to verify the feasibility and effectiveness of the developed model and method. This work is supported by an Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) Project on Intelligent Grids Under the Energy Transformed Flagship, and Project from Jiangxi Power Company.
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The Australian Federal Commissioner of Taxation recently released Draft Taxation Ruling TR 2008/D3 with the stated purpose of clarifying ‘what profits derived from the leasing of ships or aircraft fall within the ship and aircraft articles of each of Australia’s tax treaties’. In particular, TR 2008/D3 explains the taxing rights over different types of leasing profits, such as a full basis lease in respect of any transport by a ship operated in international traffic and bareboat leases which are ancillary to the lessor transport operations of ships in international traffic. This article outlines the Commissioner’s views on the application of the standard ships and aircraft articles in the tax treaties to which it is a party as well as considering the major variations on the standard adoption. In doing so, guidance is provided as to the allocation of taxing rights of ship and aircraft leasing profits under Australia’s tax treaties.
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The taxation of multinational banks currently is governed by the general principles of international tax. However, it is arguable that there are characteristics exclusive to multinational banks that may warrant the consideration of a separate taxing regime. This article argues that because of the unique nature of multinational banks, the traditional international tax rules governing jurisdiction to tax and allocation of income do not produce a result which is optimal, as it does not reflect economic reality. That is, the current system does not produce a result that accurately reflects the economic source of the income or the location of the economic activity. The suggested alternative is unitary taxation using global formulary apportionment. Formulary apportionment is considered as an alternative that reflects economic reality by recognising the unique nature of multinational banks and allocating the income to the location of the economic activity. The unique nature of multinational banking is recognised in the fact that formulary apportionment does not attempt to undertake a transactional division of a highly integrated multinational entity. Rather, it allocates income to the jurisdictions based on an economically justifiable formula. Starting from this recognition, the purpose of this article is to demonstrate that formulary apportionment is a theoretically superior (or optimal) model for the taxation of multinational banks. An optimal regime, for the purposes of this article, is considered to be one that distributes the taxing rights in an equitable manner between the relevant jurisdictions, while, simultaneously allowing decisions of the international banks to be tax neutral. In this sense, neutrality is viewed as an economic concept and equity is regarded as a legal concept. A neutral tax system is one in which tax rules do not affect economic choices about commercial activities. Neutrality will ideally be across jurisdictions as well as across traditional and non-traditional industries. The primary focus of this article is jurisdictional neutrality. A system that distributes taxing rights in an equitable manner between the relevant jurisdictions ensures that each country receives its fair share of tax revenue. Given the increase in multinational banking, jurisdictions should be concerned that they are receiving their fair share. Inter-nation equity is concerned with re-determining the proper division of the tax base among countries. Richard and Peggy Musgrave argue that sharing of the tax base by countries of source should be seen as a matter of inter-nation equity requiring international cooperation. The rights of the jurisdiction of residency will also be at issue. To this extent, while it is agreed that inter-nation equity is an essential attribute to an international tax regime, there is no universal agreement as to how to achieve it. The current system attempts to achieve such equity through a combined residency and source regime, with the transfer pricing rules used to apportion income between the relevant jurisdictions. However, this article suggests, that as an alternative to the current regime, equity would be achieved through formulary apportionment. Opposition to formulary apportionment is generally based on the argument that it is not a theoretically superior (or optimal) model because of the implementation difficulties. Yet these are two separate issues. As such, this article is divided into two core parts. The first part examines the theoretical soundness of the formulary apportionment model concluding that it is theoretically superior to the arm’s length pricing requirement of the traditional transfer pricing regime. The second part examines the practical implications of accepting formulary apportionment as an optimal model with a view to disclosing the issues that arise when a formulary apportionment regime is adopted. Prior to an analysis of the theoretical and practical application of formulary apportionment to multinational banks, the unique nature of these banks is considered. The article concludes that, while there are significant implementation, compliance, and enforcement issues to overcome, the unitary taxation model may be theoretically superior to the current arm’s length model which applies to multinational banks. This conclusion is based on the unitary taxation model providing greater alignment with the unique features of these banks.
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In this video, text types across the screen one line at a time set to an emotive stock music soundtrack. The text combines two teen film plot descriptions into one story. This work engages with the language of Hollywood narratives. By emphasizing the potentially abstract and convoluted qualities of linguistic communication, it challenges our capacity to assimilate information into conventional narratives. It draws specific attention to the conventions of Hollywood plot development, and questions the mechanisms by which they construct and communicate meaning.
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The principles relating to the passing of risk under a contract for the sale of real property would seem to have been long settled. The rule under the general law is that the risk of loss of the subject matter under a contract for the sale of real property passes to the buyer upon the creation of a valid and binding contract. This article considers the origin of that rule, how it developed with the growth of equity, and advances the view that it is anomalous in a modern context of property dealings. In doing so, the article adverts to the variety of statutory mechanisms used to subvert the rule, few of which are of practical value. It concludes that the rule is outmoded in many respects and suggests a number of reforms which might be implemented nationally to bring consistency and simplicity to the issue of damage or destruction of improvements which are the subject of a land contract.
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Serving as a powerful tool for extracting localized variations in non-stationary signals, applications of wavelet transforms (WTs) in traffic engineering have been introduced; however, lacking in some important theoretical fundamentals. In particular, there is little guidance provided on selecting an appropriate WT across potential transport applications. This research described in this paper contributes uniquely to the literature by first describing a numerical experiment to demonstrate the shortcomings of commonly-used data processing techniques in traffic engineering (i.e., averaging, moving averaging, second-order difference, oblique cumulative curve, and short-time Fourier transform). It then mathematically describes WT’s ability to detect singularities in traffic data. Next, selecting a suitable WT for a particular research topic in traffic engineering is discussed in detail by objectively and quantitatively comparing candidate wavelets’ performances using a numerical experiment. Finally, based on several case studies using both loop detector data and vehicle trajectories, it is shown that selecting a suitable wavelet largely depends on the specific research topic, and that the Mexican hat wavelet generally gives a satisfactory performance in detecting singularities in traffic and vehicular data.
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Conventional training methods for nurses involve many physical factors that place limits on potential class sizes. Alternate training methods with lower physical requirements may support larger class sizes, but given the tactile quality of nurse training, are most appropriately applied to supplement the conventional methods. However, where the importance of physical factors are periphery, such alternate training methods can provide an important way to increase upper class-size limits and therefore the rate of trained nurses entering the important role of critical care. A major issue in ICU training is that the trainee can be released into a real-life intensive care scenario with sub optimal preparation and therefore a level of anxiety for the student concerned, and some risk for the management level nurses, as patient safety is paramount. This lack of preparation places a strain on the allocation of human and non-human resources to teaching, as students require greater levels of supervision. Such issues are a concern to ICU management, as they relate to nursing skill development and patient health outcomes, as nursing training is potentially dangerous for patients who are placed in the care of inexperienced staff. As a solution to this problem, we present a prototype ICU handover training environment that has been developed in a socially interactive virtual world. Nurses in training can connect remotely via the Internet to this environment and engage in collaborative ICU handover training classes.
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The design-build (DB) system is a popular and effective delivery method of construction projects worldwide. After owners decide to procure their projects through the DB system, they may wish to determine the optimal proportion of design to be provided in the DB request for proposals (RFPs), which serve as solicitations for design-builders and describe the scope of work. However, this presents difficulties to DB owners and there is little, if any, systematic research in this area. This paper reports on an empirical study in the USA entailing both an online questionnaire survey and Delphi survey to identify and evaluate the factors influencing owners’ decisions in determining the proportion of design to include in DB RFPs. Eleven factors are identified, i.e. (1) clarity of project scope; (2) applicability of performance specifications; (3) desire for design innovation; (4) site constraints; (5) availability of competent design-builders; (6) project control requirements; (7) user group involvement level; (8) third party requirements; (9) owner experience with DB; (10) project complexity; and (11) schedule constraints. A statistically significant agreement on the eleven factors was also obtained from the (mainly non-owner) Delphi experts. Although some of the experts hold different opinions on how these factors affect the proportion of design, these findings furnish various stakeholders with a better understanding of the delivery process of DB projects and the appropriate provision of project information in DB RFPs. As the result is mainly industry opinion concerning the optimal proportion of design, in addition and for completeness, future studies should be conducted to obtain a big picture of the optimal proportion of design by means of seeking owners’ inputs.