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81.
Josep Llosa Eduard Ayguadé Mateo Valero 《International journal of parallel programming》1998,26(2):121-142
Software Pipelining is a loop scheduling technique that extracts loop parallelism by overlapping the execution of several consecutive iterations. One of the drawbacks of software pipelining is its high register requirements, which increase with the number of functional units and their degree of pipelining. This paper analyzes the register requirements of software pipelined loops. It also evaluates the effects on performance of the addition of spill code. Spill code is needed when the number of registers required by the software pipelined loop is larger than the number of registers of the target machine. This spill code increases memory traffic and can reduce performance. Finally, compilers can apply transformations in order to reduce the number of memory accesses and increase functional unit utilization. The paper also evaluates the negative effect on register requirements that some of these transformations might produce on loops. 相似文献
82.
光纤复合架空地线(OPGW)雷击试验及分析 总被引:2,自引:2,他引:2
Liuis-RSales JosepMartin AllesandroGinocchio 《电力系统通信》2004,25(5):1-5
就IEC 60794.4.1标准所描述的雷击试验要求,对不同OPGW光缆设计进行了研究,并分析了雷击对不同OPGW缆型的影响。提高连续电流——组成部分C(最具破坏性的部分)的电荷转移量,光缆的残余抗拉强度将随之降低。当电荷转移量大于100C时,光缆被损坏程度更多地取决于光缆的直径而不是外层绞线的直径。试验结果表明,为了设计出可靠并经济的OPGW光缆,我们必须综合考虑OPGW的机械性能和依据安装地的年雷暴日水平所必需的抗雷击性能。 相似文献
83.
Antonio Rodríguez‐Ferran Josep Sarrate Antonio Huerta 《International journal for numerical methods in engineering》2004,59(4):577-596
Numerical modelling of porous flow in a low‐permeability matrix with high‐permeability inclusions is a challenging task because the large ratio of permeabilities ill‐conditions the finite element system of equations. We propose a coupled model where Darcy flow is used for the porous matrix and potential flow is used for the inclusions. We discuss appropriate interface conditions in detail and show that the head drop in the inclusions can be prescribed in a very simple way. Algorithmic aspects are treated in full detail. Numerical examples show that this coupled approach precludes ill‐conditioning and is more efficient than heterogeneous Darcy flow. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
84.
Viviane Torres Da Silva Carlos J. P. De Lucena 《Autonomous Agents and Multi-Agent Systems》2004,9(1-2):145-189
In this paper we propose a multi-agent system modeling language (MAS-ML) that extends UML (Unified Modeling Language) based on structural and dynamic properties presented in a conceptual framework (metamodel) called Taming Agents and Objects (TAO). Our focus is the adaptation according to TAO concepts of the static Class diagram and the interaction Sequence diagram proposed by UML. These two diagrams have been chosen because they are the most commonly used and because it is possible to use them to illustrate both the structural and dynamic aspects of TAO metamodel. We propose a conservative extension of the UML metamodel, which includes agent-related notions that are part of the TAO conceptual framework while preserving all object-related concepts, which constitute the UML metamodel. The main difference between our approach and the others presented in the literature is the clear definition and representation of the elements that compose MASs and their corresponding behavior. In order to extend UML with TAO non-object concepts, it is not possible to use only the three basic extensions mechanisms provided by UML and new metaclasses and stereotypes have been created and associated with the UML metamodel. 相似文献
85.
Industrial control applications are usually developed in two phases: control design and real-time system implementation. In the control design stage a regulator is obtained and later it is translated into an algorithm in the implementation phase. Traditionally, these two phases have been developed in separate ways. Recently, some works have pointed out the necessity of the integration of the control design and its implementation. One of these works reduce the delay variance of control tasks (defined as the control action interval (CAI) and data acquisition interval (DAI) parameters) splitting every task into three parts. The CAI reduction method highly reduces the delay variance and improves the control performance. This work shows how to evaluate these delays under static and dynamic scheduling policies. A new task model is proposed in order to reduce the CAI and DAI parameters, which implies an improvement in the control performance. The new task model will be implemented in a real process, and the experimental measurements will show how, effectively, the control performance is highly improved with the methods presented in this paper. 相似文献
86.
Bacterial polysaccharides and polyhydroxyalkanoates present physical and chemical characteristics that impart them diverse functional properties, including the ability to produce structures from nano- to macroscale (e.g., spheres, capsules, beads). Such structures may be specially designed to fulfill the requirements of specific applications in different areas, either alone or conjugated with other polymers by means of ionic interactions, hydrogen bonding, or chemical reactions. The interest on using such biomaterials has been increasing due to their unique functional properties, nontoxicity, biodegradability, and biocompatibility. The fields of application of bacterial polymers-based structures include drug delivery, biomedicine, food products, environment, and agriculture, among others. 相似文献
87.
88.
J. Rodríguez‐Ramírez L. Mndez‐Lagunas A. Lpez‐Ortiz S. Sandoval Torres 《Journal of food science》2012,77(12):R146-R154
Abstract: This review presents the concepts involved in determining the density of foodstuffs, and summarizes the volumetric determination techniques used to calculate true density and apparent density in foodstuffs exposed to the drying process. The behavior of density with respect to moisture content (X) and drying temperature (T) is presented and explained with a basis in changes in structure, conformation, chemical composition, and second‐order phase changes that occur in the processes of mass and heat transport, as reported to date in the literature. A review of the empirical and theoretical equations that represent density is presented, and their application in foodstuffs is discussed. This review also addresses cases with nonideal density behavior, including variations in ρs and ρw as a function of the inside temperature of the material, depending on drying conditions (X, T). A compilation of studies regarding the density of dehydrated foodstuffs is also presented. 相似文献
89.
Jose Luis Fernandez-Marquez Giovanna Di Marzo Serugendo Sara Montagna Mirko Viroli Josep Lluis Arcos 《Natural computing》2013,12(1):43-67
In the last decade, bio-inspired self-organising mechanisms have been applied to different domains, achieving results beyond traditional approaches. However, researchers usually use these mechanisms in an ad-hoc manner. In this way, their interpretation, definition, boundary (i.e. when one mechanism stops, and when another starts), and implementation typically vary in the existing literature, thus preventing these mechanisms from being applied clearly and systematically to solve recurrent problems. To ease engineering of artificial bio-inspired systems, this paper describes a catalogue of bio-inspired mechanisms in terms of modular and reusable design patterns organised into different layers. This catalogue uniformly frames and classifies a variety of different patterns. Additionally, this paper places the design patterns inside existing self-organising methodologies and hints for selecting and using a design pattern. 相似文献
90.
The aim of this paper is to examine how wine firms implement their marketing strategies based on the recognition of market opportunities by their Chief Executive Officers (CEOs). Firstly, we describe the marketing activities in 69 traditional Chilean wine firms. Then, in-depth interviews with CEOs of two wineries are analysed using cognitive maps to uncover the cognitive processes responsible for recognizing and executing market activities. Our findings indicate that there is a similar set of strategic resources across the wineries, but the CEOs’ different perceptions of the usefulness of these resources in the implementation of marketing strategies have led them to select diverse strategies to increasing both the price per bottle and wine sales. This paper makes two contributions. Firstly, we compare the benefit of implementing traditional and relational marketing strategies in the Chilean wine industry. Secondly, we show that the CEOs’ perception of feedback processes among the available resources affects the recognition of market opportunities and the marketing strategy in wine firms. 相似文献