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101.
102.
Maury Wright 《电子设计技术》2006,13(12):170-170
2004年,我们考虑将全球报道作为每年的一项工作,它将使我们能充分利用我们在全球的编辑资源,并以我们的文章为全球读者服务。读者似乎很欣赏创刊版和2005版,因此我们现在提供第三期年度报道。全世界的工程师都面临着按照国际标准和规定来做设计,其工作的全球市场潜力等全球性问题。我们相信:您将会发现《全球报道3》在这两方面都会给予您启发。今年,我们的全球报道侧重于各种围绕四个设计领域的全球性问题。模拟设计,电源系统设计,基于微处理器的设计、芯片设计。本期全球报道都包含一篇针对上述每个领域的基础文章。此外,每个部分都包含若干篇附文,用其它学科、产品和应用的相关信息来实现全面覆盖,例如测试、可编程逻辑和无线通信。 相似文献
103.
Richard Ashley David Blackwood Nicki Souter Sarah Hendry Jim Moir Judith Dunkerley John Davies David Butler Andrew Cook Jim Conlin Martin Squibbs Andrew Britton Peter Goldie 《Canadian Metallurgical Quarterly》2005,131(2):206-215
The study presented is an example of the assessment of the relative sustainability of either option for disposal of domestic sanitary waste, either via the toilet or via the solid waste route. This required an evaluation of the total (social, economic, environmental, and technical) benefit/cost of implementing and adopting the alternative routes and an assessment of public responsiveness to encouragement to change sanitary waste disposal practices. It illustrates how, even for an apparently straightforward either/or question, the assessment of relative sustainability is complex and the amount of data needed to quantify sustainability indicators is prodigious. The study also provides an appraisal of the effectiveness of public campaigns to reduce waterborne disposal. Important information regarding public attitude and behavior in relation to wastewater systems has been acquired and lessons for ways of encouraging behavioral change to more sustainable ways of living have been gleaned. 相似文献
104.
Satellite-Based Energy Balance to Assess Within-Population Variance of Crop Coefficient Curves 总被引:5,自引:0,他引:5
Masahiro Tasumi Richard G. Allen Ricardo Trezza James L. Wright 《Canadian Metallurgical Quarterly》2005,131(1):94-109
Quantifying evapotranspiration (ET) from agricultural fields is important for field water management, water resources planning, and water regulation. Traditionally, ET from agricultural fields has been estimated by multiplying the weather-based reference ET by crop coefficients (Kc) determined according to the crop type and the crop growth stage. Recent development of satellite remote sensing ET models has enabled us to estimate ET and Kc for large populations of fields. This study evaluated the distribution of Kc over space and time for a large number of individual fields by crop type using ET maps created by a satellite based energy balance (EB) model. Variation of Kc curves was found to be substantially larger than that for the normalized difference vegetation index because of the impacts of random wetting events on Kc, especially during initial and development growth stages. Two traditional Kc curves that are widely used in Idaho for crop management and water rights regulation were compared against the satellite-derived Kc curves. Simple adjustment of the traditional Kc curves by shifting dates for emergence, effective full cover, and termination enabled the traditional curves to better fit Kc curves as determined by the EB model. Applicability of the presented techniques in humid regions having higher chances of cloudy dates was discussed. 相似文献
105.
Neiss Michelle B.; Stevenson Jim; Sedikides Constantine; Kumashiro Madoka; Finkel Eli J.; Rusbult Caryl E. 《Canadian Metallurgical Quarterly》2005,89(4):593
Complementary approaches examined the relations among executive self, self-esteem, and negative affectivity. A cross-sectional (N = 4,242) and a longitudinal (N = 158) study established that self-esteem mediated the relation between executive self and negative affectivity. A 3rd study (N = 878 twin pairs) replicated this pattern and examined genetic and environmental influences underlying all 3 phenotypes. Covariation among the 3 phenotypes reflected largely common genetic influences, although unique genetic effects explained variability in both executive self and negative affectivity. Executive self was influenced by shared environmental influences unique from those affecting self-esteem and negative affectivity. Nonshared environmental influences accounted for the majority of variance in each construct and were primarily unique to each. The unique genetic and nonshared environmental influences support the proposition that the executive self, self-esteem, and negative affectivity capture distinct and important differences between people. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
M. Dolores Jiménez-Gamero Juan Luis Moreno-Rebollo Juan M. Muñoz-Pichardo Ana M. Muñoz-Reyes 《TEST》2005,14(2):515-542
One of the areas of Statistics in which the influence analysis has been widely studied is the multiple linear regression model.
Nevertheless, the influence diagnostics proposed in this context cannot be applied to regression in complex survey, under
randomized inference, since the i.i.d. case does not incorporate any probability weighting or population structure, such as
clustering, stratification or measures of size into the analysis.
In this paper we introduce some influence diagnostics in regression in complex survey. They are built on the conditional bias
concept (Moreno-Rebollo et al., 1999). We emphasize the similarities and differences of the proposed measures with respect
to the existing ones for the i.i.d. case.
Research partly supported by the Spanish MCYT grant BFM2001-3844 and Spanish MEC grant MTM2004-0111433. 相似文献
107.
Rodríguez José Ignacio Jiménez José Manuel Funes Francisco Javier García de Jalón Javier 《Multibody System Dynamics》2003,10(2):177-199
In this paper a prototype of a computer program for multi-bodysimulation based on the use of CORBA, Java and XML is presented. Thisprototype makes use of a recursive dynamic formalism which outperformsmany implementations based on global formulations. The prototypepresented has been implemented using distributed Object OrientedProgramming techniques. The definition of the multi-body system is donethrough a data file defined using XML (eXtendible Markup Language). Thisprototype implements a `simulation service' on a network of computers,following a client-server scheme. This `simulation service' can operatein two different ways: offering a remote simulation on the server, orproviding a Java compiled code for local simulation on the client. Thepaper describes the practical implementation of such a service. The useof recursive functions and OOP permits the implementation of ageneral-purpose simulation code, which is compact, clear, clean,re-usable and easy to maintain. Once this Java code is compiled, it isstored in less than 125 Kbytes (including the numerical integrators).The Java programming language is used in order to assure compatibilitybetween different platforms. Finally, practical examples which make useof this approach are shown. 相似文献
108.
J. L. Pons R. Ceres A. R. Jiménez L. Calderón J. M. Martin 《Journal of Intelligent and Robotic Systems》1997,18(3):277-287
The precise control of manipulators depends nonlinearly on the velocity of the motion as well as on manipulator configuration and commanded acceleration requiring complex control strategies. This paper presents a useful tool for identifying and quantifying nonlinear effects appearing during the motion of any manipulator, the Nonlinear Performance Index (npi). The npi takes into account not only the geometrical parameters defining the manipulator but also its structural dynamics through the use of inertial parameters like mass, inertia, centre of mass... The npi can be used in the design stage for analysing and reducing these undesirable nonlinear effects in any general motion or in the trajectory planning looking for paths along which more precise control is expected. The last part of the paper shows how this design optimisation and path planning has been applied to the Agribot, a fruit picking robot designed at the IAI. 相似文献
109.
110.
A simple method is presented for evaluating wall shear stresses from known flow histories in unsteady pipe flows. The method builds on previous work by Trikha, but has two important differences. One of these enables the method to be used with much larger integration time steps than are acceptable with Trikha’s method. The other, a general procedure for determining approximations to weighting functions, enables it to be used at indefinitely small times (high frequencies). The method is applicable to both laminar and turbulent flows. 相似文献