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991.
General competence trust among supply chain partners, referring to the trust that a partner holds the general ability of fulfilling contracts, is a critical factor to ensure effective cooperation in a supply chain, especially in the current financial crisis. The method of supply chain trust diagnosis (SCTD) is to evaluate whether or not a partner holds such competence. This research devotes to an early investigation on diagnosing competence trust of supply chain with the method of inductive case-based reasoning ensemble (ICBRE). The so-called supply chain trust diagnosis with inductive case-based reasoning ensemble consists of five levels, that is, information level, the level of ratios of general competence states, the level of inductive case-based reasoning, ensemble level, and diagnosis result level. Knowledge for diagnosing competence trust, which composes of a case base, is hidden in data represented by ratios of general competence states. Inductive approach is combined with randomness to construct diverse and good member methods of inductive case-based reasoning. Finally, simple voting is used to integrate outputs of member inductive case-based reasoning methods in order to produce the final diagnosis on whether or not a partner holds the general ability of fulfilling contracts. We statistically validated results of the method of supply chain trust diagnosis with inductive case-based reasoning ensemble by comparing them with those of multivariate discriminant analysis, logistic regression, single Euclidean case-based reasoning, and single inductive case-based reasoning. The results indicate that the method of supply chain trust diagnosis with inductive case-based reasoning ensemble significantly improves predictive capability of case-based reasoning in this problem and outperforms all the comparative models by group decision of several decision-making agents and non-strict assumptions like statistical methods.  相似文献   
992.
Economic contribution rate of education (ECRE) is the key factor of education economics. This article selected China, South Korea, United States and other countries for a total of 15 samples, and put the data of the same period under the framework of soft computing, to simulate the production chain of “education–potential human capital–actual human capital–economic growth”. The basic idea is: Firstly, 15 countries are softly categorized according to the level of science and technology (S&T) progress. Secondly, potential human capital and actual human capital establish the internal correlation (fuzzy mapping) in the same classification, and we conceptualize actual human capital as one production factor, joined with the other two production factors, fixed asset and land, to set up the fuzzy mapping to economic growth., and then calculate economic contribution rate of education of China and foreign by two fuzzy mapping of them. Thirdly, this paper analyzes the present state and differences in the development of education between China and foreign according to different ECRE, and offers proposals for promoting the education in China.  相似文献   
993.
Next-generation scientific applications feature complex workflows comprised of many computing modules with intricate inter-module dependencies. Supporting such scientific workflows in wide-area networks especially Grids and optimizing their performance are crucial to the success of collaborative scientific discovery. We develop a Scientific Workflow Automation and Management Platform (SWAMP), which enables scientists to conveniently assemble, execute, monitor, control, and steer computing workflows in distributed environments via a unified web-based user interface. The SWAMP architecture is built entirely on a seamless composition of web services: the functionalities of its own are provided and its interactions with other tools or systems are enabled through web services for easy access over standard Internet protocols while being independent of different platforms and programming languages. SWAMP also incorporates a class of efficient workflow mapping schemes to achieve optimal end-to-end performance based on rigorous performance modeling and algorithm design. The performance superiority of SWAMP over existing workflow mapping schemes is justified by extensive simulations, and the system efficacy is illustrated by large-scale experiments on real-life scientific workflows for climate modeling through effective system implementation, deployment, and testing on the Open Science Grid.  相似文献   
994.
Supersonic jet pumps are simple devices with no moving parts, where a high velocity (primary) flow is used to pump a second fluid. In this paper, Computational Fluid Dynamics (CFD) is combined with an optimization framework in order to develop a tool for the rapid generation of jet pump designs. A key feature of the problem formulation is the transformation of the jet pump design parameters in terms of geometric ratios. This approach dramatically reduces the number of unrealistic designs covered by the Design of Experiments. Optimal Latin Hypercubes for surrogate model building and model validation points are constructed using a permutation genetic algorithm and design points are evaluated using CFD. Surrogate models of primary and entrained flow rates are built using a Moving Least Squares approach. A series of optimizations for various pump sizes are performed using a genetic algorithm and Sequential Quadratic Programming, with responses calculated from the surrogates. This approach results in a set of optimized designs, from which pumps for a wide range of flow rates can be interpolated.  相似文献   
995.
该文引入speedup作为并行程序的性能评测指标,分析了并行程序在不同类型和不同数量的客户虚拟机中运行的性能差异,实验表明,MPI并行程序在xVM虚拟化环境中的运行性能接近非虚拟化本地主机的性能,在半虚拟化环境中的并行程序性能超过全虚拟化环境中的并行程序性能。  相似文献   
996.
经食道心房调搏的放射性核素心血管造影   总被引:1,自引:0,他引:1  
本文应用反符合电路剔除调搏脉冲干扰的方法,制成经食道心房调搏心电心音门电路触发装置,用于经食道心房调搏的核素心血管造影。参考Tzivoni标准,当逐级增加调搏心率至140次/min或亚极量心率后发现:冠心病人有调搏后EF降低;急性心肌梗塞病人EF减低更为明显,并呈室壁反向运动。因此,心房调搏核素心血管造影有助于冠心病,特别是心肌梗塞的诊断。  相似文献   
997.
Abstract. We provide a stochastic proof of the inequality ρ(A?A+B?B) ≥ρ(A?A), where ρ(M) denotes the spectral radius of any square matrix M, i.e. max{|eigenvalues| of M}, and M?N denotes the Kronecker product of any two matrices M and N. The inequality is then used to show that stationarity of the bilinear model will imply stationarity of the linear part, i.e. the linear ARMA model for r= 1 and q= 1. Furthermore, it is shown that stationarity of the subdiagonal model, i.e. the bilinear model with bij=0 for i< j, again implies stationarity of its linear part, provided that the stationarity condition given by Bhaskara Rao and his colleagues is met. Interestingly, the conclusion that stationarity of the subdiagonal models, implies that the linear component models cannot be extended to the general non-subdiagonal bilinear models. The last observation is demonstrated via a simple example with p=m= 1, r= 0 and q= 2.  相似文献   
998.
Ag-3a/oMg was oxidized in air over the range of 400–900°C. Internal-oxide bands of MgO formed approximately parallel to the surface, the first band appearing at some finite, but irregular depth below the surface. The region between the surface and the first band appeared to be free of precipitates, but TEM showed that very small clusters, about 50 Å in diameter, formed in the PFZ, causing significant hardness (greater than 300 VHN). The clusters contain more oxygen than that corresponding to stoichiometric MgO. The hardness between oxide bands was also high, but not as high as in the PFZ. The kinetics of thickening of the internal-band region followed the parabolic rate law between 400 and 700° C, with departures from the parabolic law occurring at higher temperatures. The activation energy for the parabolic rate constants was 19.4 Kcal/mol, a value less than the total for oxygen diffusion and oxygen dissolution. The reaction front was planar and parallel to the surface prior to band formation at temperatures of 400–600° C. Nucleation of the first band resulted in nonplanar and nonparallel oxide. Little or no correlation existed between grain boundaries and oxide formation. Nodules of virtually pure silver formed on the surface initially at grain boundaries and subsequently within grains. Nodule formation is attributed to stress-enhanced (resulting from strains associated with precipitation) diffusion of silver to the surface via dislocation pipes. Internal-band formation is discussed in terms of prior data in the literature and various models. It is thought that stress effects (induced by precipitation), nucleation, and clustering of oxygen with Mg play significant roles in causing internal-band formation.  相似文献   
999.
After analysing different plasma processes, we have designed and developed a 14kW d.c. plasma unit for generating ultrafine powders. Experiments to characterize the torch demonstrated that it is possible to operate the plasma unit over a wide range of conditions without losing its discharge stability. Temperature distribution profiles were determined radially as well as axially in the reaction chamber, and the efficiency of the torch was calculated for a fixed power input. Ultrafine powders of Ta, Mo and W were synthesized, and size and size distribution obtained. The particle size was found to be 0.03–0.1 m, with a perfect spherical shape. The analysis of the samples is discussed.  相似文献   
1000.
采用虚拟仪器技术,对CSY10B型传感器的输出进行了数据采集和处理,设计了传感器静态性能测试系统。在Windows系统环境下,利用LabVIEW软件编程,构建虚拟仪器,实现了对传感器输出电压的实时测量、显示、记录;同时对其输出电压数据进行数据拟合,确定了其最佳拟合曲线,实现了对传感器的静态特性的自动分析与测定。所提出的传感器静态性能测试系统具有良好的人机交互界面,简单实用。  相似文献   
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