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31.
《Calphad》2020
In this study, the Ga–Te binary system was reassessed by means of the CALPHAD method using a modified lattice stability parameter for Te as well as experimental data for this binary system. The two-sublattice ionic solution model was applied for the liquid phase, and the intermediate phases were described by the sublattice model. A set of self-consistent thermodynamic parameters was optimized for all the phases in the Ga–Te binary system, which reproduced the phase diagram and the thermodynamic properties well. Using the reevaluated Ga–Te system, previously assessed Ga–Se system, and modified Se–Te system, a critical evaluation of the Ga–Se–Te ternary system was performed. The calculated vertical sections, isothermal sections, and liquidus projection agreed reasonably well with the experimental data. Immiscibility in the liquid phase was observed, and the origin of this behavior is discussed from a thermodynamic perspective. 相似文献
32.
33.
以井下供电监控及防越级跳闸运用为对象开展探究。在分析矿井供电系统运行中现存主要问题的基础上,对供电监控与防越级跳闸系统整体应用的积极意义进行了分析和总结,希望能够让更多矿井技术人员了解供电监控及防越级跳闸系统的优越性,为其在矿井中的广泛推广普及提供便利,为煤矿行业更加高效地发展提供帮助。 相似文献
34.
35.
焦炉生产是典型的大惯性、非线性、时变快的复杂系统,以“火落温度”为基础的焦炉前反馈热工控制系统,通过立火道温度自动测量与人工测温相关性分析、粗煤气温度测量与火落判断、标准温度的优化等运行实践,达到了自动火落时间判断、标准温度指导、加热和燃烧优化、高低温炉号判别等目的,对于稳定炉温、降低回炉煤气消耗、提高焦炭质量以及推进焦化企业技术进步具有重要意义。 相似文献
36.
Chang-Won Kim Wi Sung Yoo Hyunsu Lim Ilhan Yu Hunhee Cho Kyung-In Kang 《International Journal of Project Management》2018,36(5):730-743
An early-warning performance monitoring system (EPMS) is proposed to objectively measure and monitor the performance of a project for early detection of inherent poor performance problems. The EPMS is built based on project progress data and consists of a database of business information, an optimized theoretical model used as a performance measurement baseline, and an index for monitoring and forecasting the performance. By monitoring the performance through an application of the EPMS to the Korean construction project, the quarterly variation of index was found to differ by project type. These results could explain the environmental changes in the project execution. Therefore, the EPMS is expected to be an alternative for objective performance monitoring and forecasting while applying the existing methods is difficult because of the limited available data on performance indicators. The development procedures may also be useful to researchers interested in approaches to quantitatively analyze trends in various industries. 相似文献
37.
HUANG Xiao-hua 《广东电脑与电讯》2020,1(1-2):25-27
This paper firstly describes the current situation and limitations of learning evaluation and assessment in colleges and uni-
versities; then, it analyzes the possibility of implementing the learning evaluation and assessment based on "dynamic learning data
analysis"; then, it describes the design process of the learning evaluation and assessment system in detail; finally, it determines the
various assessment items and carries out quantitative processing to better apply them to actual teaching. 相似文献
38.
随着高校办学规模的不断扩大,原基于师生服务中心的现场人工报修方式,已无法满足日益增长的后勤报修维修的需求。根据学校的实际情况,对学校后勤管理系统进行分析,得出高职院后勤管理系统应满足在线报修、在线查看、维修反馈、在线评价等功能的需求;同时对高校后勤报修系统进行系统架构设计、网络架构设计、UML类图设计、数据库设计等。通过C#完成系统的编写,最终实现后勤报修系统的开发。 相似文献
39.
LUO Jin-ling LIU Luo-ren 《广东电脑与电讯》2020,1(4):11-13
In view of the problems in the construction of characteristic professional groups in higher vocational colleges, the professional group of "intelligent manufacturing" is taken as the research object, and the "platform + module" suitable for the development
of the industry will be constructed according to the content of the vocational ability planning courses of the post group. The curriculum system establishes the framework of professional groups, and explores and forms a strategic study to optimize and integrate professional group resources. 相似文献
40.
Hashim A.
Hashim 《国际强度与非线性控制杂志
》2020,30(10):3848-3870
》2020,30(10):3848-3870
This paper introduces two novel nonlinear stochastic attitude estimators developed on the Special Orthogonal Group with the tracking error of the normalized Euclidean distance meeting predefined transient and steady‐state characteristics. The tracking error is confined to initially start within a predetermined large set such that the transient performance is guaranteed to obey dynamically reducing boundaries and decrease smoothly and asymptotically to the origin in probability from almost any initial condition. The proposed estimators produce accurate attitude estimates with remarkable convergence properties using measurements obtained from low‐cost inertial measurement units. The estimators proposed in continuous form are complemented by their discrete versions for the implementation purposes. The simulation results illustrate the effectiveness and robustness of the proposed estimators against uncertain measurements and large initialization error, whether in continuous or discrete form. 相似文献