模拟多孔介质中质量输运现象有限颗粒法的应用

有限颗粒法是一种新的颗粒跟踪法,特别适合模拟污染物的运移过程。用有限颗粒法对多孔介质中纵向弥散度进行识别。纵向弥散度是表征含水层中介质弥散特征的重要参数．也是一个很难确定的参数。给出具体算例,并做进一步的讨论。     

任务驱动的大学信息技术教学改革

针对高校学生的特点,以提高学生对信息技术知识结构和应用能力为目标．进行基于任务驱动教学方法的改革。任务驱动教学可以大大提高学生学习的积极性．同时也取得显著的教学成果。现就教学过程提供一些实践依据和方法措施以供借鉴。     

基于博弈论的社交网络的控制方法

社交网络虽然实现了网络化的人际信息交流和交友．但同时也存在着大量的例如个人隐私信息泄露等问题。面对这种情况,计算机学术界提出一种基于博弈论的能够避免泄露用户隐私信息的新型的社交网络的访问控制方法。就这一基于博弈论的社交网络控制方法进行相关的简述和分析,以便于人们了解和认识这种社交网络的博弈论控制方法。     

低负荷维氏硬度法的负荷选择

本文按照维氏硬度测定的技术条件,将基本公式H_v=1854P/D~2加以变换,从而得到一些较为简单的数学关系式.利用这些关系式,可以对不同金属薄带材料,很容易计算出较合理的负荷大小,既能保证不被"打穿",也使视场内有一个适合观测的压痕图象.     

让案例教学走进高职计算机学科

"案例教学法"(CaseStudy)是一种以案例为基础的教学法,把真实的情景进行典型化处理后供学生思考分析和决断,让学生分组自助谈论和研究,从而提高学生对于问题的分析和解决的能力。     

相关函数脉冲响应法系统实时辨识

结合了相关函数法和脉冲响应法两种经典系统辨识方法原理,在随机信号干扰的情况下,设计对系统实现实时辨识的仿真软件,获得系统的非参数模型。该仿真设计中,以M序列作为输入信号,白噪声信号作为干扰信号,进行了Matlab仿真实验,讨论了M序列的幅值,采样时间和周期长度对系统辨识效果的影响,以及分析M序列的选取方法来减少系统辨识误差。     

Cu—Cr合金电极触头板铸件的熔制

含０．４％～１．０％Ｃｒ的Ｃｕ－Ｃｒ合金具有优良的导电、导热性能，铸件经热处理强化后可获得较高的综合力学性能。近年来该合金作为一种新材料被广泛地用于制作电子工业、电器设备上的电极触头板、接触环、夹持体等零件。Ｃｕ－Ｃｒ合金存在易氧化吸气、凝固范围窄、收缩较大、易形成集中缩孔等缺陷，这些铸造特性给生产优良的Ｃｕ－Ｃｒ合金铸件带来一定的困难。以采用常规的熔炼设备和造型材料熔铸出Ｃｕ－Ｃｒ合金铸件——高压大电流电极触头板为例讨论这一熔铸的工艺方法。     

Simulation Method of Dynamic Characteristics of Turbine Flow Sensor

Computational Fluid Dynamics (CFD) simulation is one of the important methods to study the performance and in-fluencing factors of turbine flow sensors. According to the working characteristics of the turbine flow sensor, the passive simulation method based on the six degrees of freedom (6-DOF) model and dynamic mesh is proposed in this paper. The reliability of the simulation method is verified by steady-state experiments and unsteady-state experiments. The results show that the trend of meter factor with flow rate acquired from the simulation is close to the experimental results, and the deviation between the simulation result and the experiment result is low with a maximum deviation of 2.88%. In the unsteady simulation study, the impeller speed changes with the inlet velocity of the turbine flow sensor, which has a good follow-up. The passive simulation method can be used to predict the dynamic performance of the turbine flow sensor.     

Modeling of Intercritical Heat Treatment of DP and TRIP Steels

The final microstructure of DP and TRIP assisted steels can evolve after hot working (hot rolling) or during post heat treatment process. In the formation of the final structure a number of different technological parameters have important roles, e.g. end temperature of rolling, cooling rates, temperature of intercritical annealing, etc. As a result of the individual factors and their combinations a lot of product technology routes are feasible. The effect of the different combinations of these technological parameters on the microstructure can be mapped by the special Jominy end-quench test (so called intercritical Jominy end-quench test) described in this paper. Unlike the traditional Jominy test, in this case there is a partial anstenizing between A1 and A3 temperatures which results in a given amount of ferrite in the microstructure before quenching. The method developed can be applied for mapping DP and TRIP assisted steels' microstructure in a wide range of technological parameters. The analysis of measured and calculated data can help us find the technological parameters optimal from the microstructural point of view.     

关于复杂黄铜的等效方法及其它

在复杂黄铜等效变换的多元变化过程中，存在着第三种当量系数Ｉ。它是确保合金转化为二元形式所必不可少的导向给定值，是一个定位常数。找出了Ｋ＋Ｊ＝０的误解的产生原因，论证了Ｋ＋Ｊ＝１所在达的过程的实质。指出用二元相图理解等效变换这一三元变化过程的认识误区。