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991.
闪速吹炼技术在祥光铜业的应用 总被引:1,自引:0,他引:1
袁剑平 《有色金属(冶炼部分)》2007,(2):40-43
介绍了闪速吹炼工艺在祥光铜业工程中的应用情况及闪速吹炼工艺过程和主要的工艺设备,并列举了部分设计指标。 相似文献
992.
近年高速工具钢的发展概况 总被引:11,自引:1,他引:11
概述了高速工具钢钢种、工艺和基础研究的近期发展;并叙述了低合金高速钢、粉末高速钢以及高速钢表面热处理的发展动态。 相似文献
993.
针对当前需求优先级排序方法中,将用户需求放在同一层次上进行比较,设定优先级,而对需求层次性考虑得不多。从系统的整体性和需求的层次性出发,提出以解释结构模型和层次分析法相结合的需求优先级排序方法,其中用解释结构模型对需求进行结构分析和分层处理,对最上层的需求使用层次分析法进行需求优先级排序,将该方法命名为SAHP。在案例分析中,借助需求模式,对推广后的案例进行优先级排序,来说明该方法具有很好的通用性,给出案例分析和与AHP进行了比较。结果表明性能总体上好于AHP方法,该方法能够提高需求优先级设定的合理性,降低因需求导致项目失败的风险。 相似文献
994.
995.
In a 2 × 2 factorial design the effects of (1) information presentation format and (2) contextual interference on training behavior, transfer performance and mental effort were studied for learning troubleshooting skills with a computer-based simulation. Participants studied information about the functioning of an alcohol distillery system (system principles) prior to practicing troubleshooting skills. Regarding the first factor, an expository (Exp) format, in which system principles, examples and a troubleshooting strategy were presented in a textual form, was compared to an inquisitory (Inq) format, in which participants had to predict the behavior of the system after they studied the system principles and in which demonstrations of the troubleshooting strategy were given. With regard to the second factor, a low contextual interference (LCI) condition in which participants practiced to diagnose types of system failures in a blocked schedule was compared to a high contextual interference (HCI) condition, in which different failure types were practiced in a random schedule. The main hypothesis is that the Inq and HCI conditions promote the development of cognitive schemata that enable learners to diagnose a malfunctioning system component by interpreting symptoms in terms of violations of system principles. Hence, they are expected to show higher transfer performance than participants in the traditional Exp and LCI conditions, who are believed to develop schemata containing associations between symptoms and malfunctioning components that are context-bound and less useful for diagnosing new failures. Contrary to the predictions, the traditional conditions (Exp and LCI) showed higher performance on a transfer test two weeks after training. Possible explanations for this result are discussed. 相似文献
996.
The inhomogeneity is introduced by a nonzero density gradient which separates the plasma into two different regions where plasma density are constant. The Alfvén waves, the phase mixing and the fast magnetosonic wave are excited by the boundary condition in inhomogeneous magnetized plasma. By using the Hall–magnetohydrodynamics(MHD) model, it is found that there are Alfvén waves in the homogeneous regions, while the phase mixing appears in the inhomogeneous region. The interesting result is that a fast magnetosonic wave is excited in a different direction which has a nonzero angle between the wave propagation direction and the direction of the background magnetic field. The dependence of the propagation direction of the excited fast magnetosonic wave and its strength of the magnetic field on the plasma parameters are given numerically. The results show that increasing both the driving frequency and the ratio of magnetic pressure to thermal pressure will increase the acceleration of the electrons. The electron acceleration also depends on the inhomogeneity parameters. 相似文献
997.
基于规则的边缘连接算法在路面病害检测中的应用 总被引:1,自引:0,他引:1
本文提出了一种基于规则的边缘连接算法,此算法对通过边缘检测提取的病害边缘块进行启发式搜索,采用基于规则的方法计算边缘连接的可信度作为连接质量的度量。通过在江苏省高速公路路面病害自动检测系统中的应用,表明此方法有较高的连接效率,同时能有效地抑制噪声。 相似文献
998.
999.
A genetic algorithm approach to determine the sample size for attribute control charts 总被引:1,自引:0,他引:1
Ihsan Kaya 《Information Sciences》2009,179(10):1552-76
Determining the sample size for control charts (CCs) is generally an important problem in the literature. In this paper, Kaya and Engin’s [?. Kaya, O. Engin, A new approach to define sample size at attributes control chart in multistage processes: an application in engine piston manufacturing process, Journal of Materials Processing Technology 183 (2007) 38-48] model based on minimum cost and maximum acceptance probability to determine the sample size for attribute control charts (ACCs), and solved by genetic algorithms (GAs) with linear binary representation structure, is handled to solve it by a linear real-valued representation. A new chromosome structure is also suggested to increase the efficiency of GAs. The performance of GAs depends on mutation and crossover operators, and their ratios. To determine the most appropriate operators, five different mutation and crossover operators are used and they are compared with each other. An application in a motor engine factory is illustrated. u-Control charts are constructed with respect to the sample size determined by GA in the model. The piston production stages in this factory are monitorized using the obtained control charts. 相似文献
1000.
Nazatul Aini Abd MajidMark P. Taylor John J.J. ChenBrent R. Young 《Computers & Chemical Engineering》2011,35(11):2457-2468
This paper describes the development of a new ‘cascade’ monitoring system for the aluminium smelting process that uses latent variable models. This system is based on the changes of variability patterns within a feeding cycle which are used to provide indications of faults and their possible causes. The system has been tested offline using 31 data sets. The performance of the system to detect an anode effect has been compared with a typical latent variable model that monitors the change of behaviour at every time instant. The results show that the ‘cascade’ monitoring system is able to detect abnormal events. It was possible to relate each event with specific patterns associated with abnormalities thus facilitating later fault diagnosis. 相似文献