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21.
Jerry Delli Priscoli 《国际水》2013,38(2):72-77
ABSTRACT This paper puts the accent on field measurements of the terms of the hydrological cycle, i.e., precipitation, evapotranspiration, run-off and infiltration, in order to evaluate the available water storage in surface reservoirs, in soils, in aquifers for short and long term planning. Methodological and technological improvements illustrate in this paper not only the difficulties in obtaining reliable field hydrological data but also the fact that the behavioural knowledge of each term of the hydrological cycle is compulsory in order to determine the limits of the socio-economic development which depends upon the quantity of water resources available and in order to prevent eventual irreversible degradation of the environment. No universal model exists because a model depends not only on the meteorological, hydrological andgeological conditions of the area under study but also on the planner's objectives concerning urban, industrial, navigational, agricultural and/or recreational activities. The studies of water resources are, therefore, in a permanent stage of pre-management. This is due to the fact that they have to be constantly adapted to new management conditions. This becomes more and more imperative since water resources studies have been, and still are, undertaken too often in order to solve specific and isolated problems arising from short-sighted and/or short term planning and management. 相似文献
22.
Xiaohu Yang Liping Zhao Xinyu Wang Ye Wang Jie Sun Albert Jerry Cristoforo 《Software》2012,42(2):131-157
Although quality requirements (QRs) have become a major drive in today's software development, there have been very few real‐world examples in the literature that demonstrate how to meet these requirements. This paper presents such an example. Specifically, the paper describes the design of a partition‐based distributed stock trading service system that satisfies a set of QRs related to resource utilization, performance, scalability and availability. The paper evaluates this design through detailed experiments and discusses some design alternatives and the lessons learned. Central to this design are a static load distribution strategy and a dynamic load balancing strategy. The first strategy is to achieve an initial balanced workload on the system's server cluster during the system initialization time, whereas the second strategy is to maintain this balanced workload throughout the system execution time. Together, these two strategies work in unison to ensure that the server resources are efficiently utilized; the user requests are processed with the required speed; the application is partitioned with sufficient room to scale; and the system is highly available. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
23.
Jerry Loraine 《电子设计应用》2006,(2):16-16,18,20,22,24
随着移动终端系统功能的持续增加,全球范围内的无线标准/接入技术不断面世,手持设备设计人员正面对着全新的需求。与手机设计中体积、功能不断下降的需求相比,他们现在面对的更大挑战是,用户希望在终端系统内纳入更多无线标准,从而达到永远适用,以及具有高成本效益和高连接性的 相似文献
24.
In this paper, we approach electronic commerce Customer Relationship Management (e-CRM) from the perspective of five research areas. Our purpose is to define a conceptual framework to examine the relationships among and between these five research areas within e-CRM and to propose how they might be integrated to further research this area. We begin with a discussion of each of the research areas through brief reviews of relevant literature for each and a discussion of the theoretical and strategic implications associated with some CRM technologies and research areas. Next we present our framework, which focuses on e-CRM from the five research perspectives. We then present a theoretical framework for e-CRM in terms of the five research areas and how they affect one another, as well as e-CRM processes and both performance and non-performance outcomes. 相似文献
25.
Immediate recall for spatial information was studied as a function of stimulus load under 2 display formats, 2 response formats, and 2 response set conditions. 4 groups of 10 Ss each served under 15 replications of all response-format, stimulus-load conditions; groups were distinguished on the basis of display format and set. Each S viewed either a spatial or tabular display of 14-26 geometrical stimuli for 16 sec.; he was then required to report, on either a tabular or spatial response form, the location of relevant stimuli. Correct responses and misplacement errors increased more rapidly for the spatial format as more stimuli were presented. Recoding from 1 display to the other response format did not yield serious decrements. Contrary to expectation, response set enhanced all conditions to a nearly equivalent degree. Results are interpreted in terms of the "chunking" hypothesis. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
Subramaniam Sathivel Peter J. Bechtel Jerry K. Babbitt Witoon Prinyawiwatkul Mary Patterson 《Journal of food science》2005,70(2):E57-E63
ABSTRACT: Arrowtooth flounder soluble protein powder (AFSP) and arrowtooth flounder insoluble protein powder (AFISP) were evaluated for their functional, nutritional, and rheological properties. AFSP and AFISP contained 80% and 79% protein and 5.9% and 14.9% fat, respectively. Yield of AFSP (8.6%) was less than AFISP (13.1%). AFSP and AFISP had desirable essential amino acid and mineral contents. Emulsion stability of AFSP was greater than AFISP. Fat and water absorptions (mL/g protein) were 5.2 and 1.8 for AFSP, respectively, and 3.3 and 4.2 for AFISP Mayonnaises made from AFSP had greater emulsion stability than mayonnaise made from AFISP. Mayonnaises from both AFSP and AFISP possessed pseudoplastic and viscoelastic characteristics. 相似文献
27.
The purpose of this paper is to describe the use of a minicomputer in an integrated track inspection program. The basic elements of such a program include the measuring vehicle, data reduction process, and presentation of data to the various management levels. The paper describes such a system which has been in use on the Southern Railway for over five years and points out desirable changes, problems, and economics. 相似文献
28.
Since its introduction in the mid 1960's the pulsewidth modulated (PWM) inverter has offered a number of significant advantages over other inverter types for low and medium frequency applications. The generation of an acceptable waveform at higher frequency, however, was limited by the characteristics of available power thyristors and modulator design. With the advent of the fast turn-off thyristor and advances in PWM modulator techniques, the PWM inverter now offers application advantages to 200 Hz. PWM design considerations are analyzed, with a discussion of second-generation PWM operation provided. 相似文献
29.
Jerry L. Bona Hongqiu Chen Ohannes Karakashian Michael M. Wise 《Journal of scientific computing》2018,77(3):1371-1401
The present study is concerned with the numerical approximation of periodic solutions of systems of Korteweg–de Vries type, coupled through their nonlinear terms. We construct, analyze and numerically validate two types of schemes that differ in their treatment of the third derivatives appearing in the system. One approach preserves a certain important invariant of the system, up to round-off error, while the other, somewhat more standard method introduces a measure of dissipation. For both methods, we prove convergence of a semi-discrete approximation and highlight differences in the basic assumptions required for each. Numerical experiments are also conducted with the aim of ascertaining the accuracy of the two schemes when integrations are made over long time intervals. 相似文献
30.
John McDonald Rosalee Wolfe Jerry Schnepp Julie Hochgesang Diana Gorman Jamrozik Marie Stumbo Larwan Berke Melissa Bialek Farah Thomas 《Universal Access in the Information Society》2016,15(4):551-566
Generating sentences from a library of signs implemented through a sparse set of key frames derived from the segmental structure of a phonetic model of ASL has the advantage of flexibility and efficiency, but lacks the lifelike detail of motion capture. These difficulties are compounded when faced with real-time generation and display. This paper describes a technique for automatically adding realism without the expense of manually animating the requisite detail. The new technique layers transparently over and modifies the primary motions dictated by the segmental model and does so with very little computational cost, enabling real-time production and display. The paper also discusses avatar optimizations that can lower the rendering overhead in real-time displays. 相似文献