“材料设计与系统模拟”课程的教学体系建设

本文针对"材料设计和系统模拟"课程内容多、涵盖面广等特点,探讨了该课程课堂教学和上机实践教学的体系建设。课堂教学的主体内容包括最优化实验方案设计、不同空间尺度的材料设计方法以及材料加工过程的数值模拟。上机实践教学创新性设计为正交实验方案设计和结果分析、基于相图计算的材料设计和Materials Studio在材料设计与模拟中的应用。

A Theory of Secure Mobile Computation with Confined Movement and Communication

An extended π calculus was introduced to deal with secure movement and intercommunication between agents. The system extends Nomadic-π with objective migration primitive and confined region which serves as annotation labels of agents and channels. The confined region labels were used to uniquely identify the constraints on the migration and communication of agents, with the labels, the agents could be confined in a secure subsystem and the inter-agent communication could be confined between agents located on trusted sites during computation. The operational semantics for the calculus was given out, and a type system which enforces security properties called confined migration and confined communication was developed.

USING SYSTEM SIMULATION METHOD AND CAD TECHNIQUE TO SOLVE THE MINING ENGINEERING RELIABILITY IN SURFACE MINES

Subjected to various stochastic factors, surface mining engineering reliability is difficult to solve by using general reliability mathematical method.The concept of reliability measurement is introduced; And the authors have combined system simulation method with CAD technique and developed an interactive color character graphic design system for evaluating and solving the mining engineering reliability in surface mines under the given constraints.

The design analyze of new hybrid drive concept

This paper presents the design method of hybrid drive system for the minibus with some limited conditions. The approach of design hybrid drive system is based on the dynamic modeling and simulation of the hybrid minibus with planetary gear system. The main target of the design is to obtain the optimal design with the proper hybrid drive configuration and control for a given set of design constraints. In oder to meet the design target, it＇s necessary to adjust some parameters such as mechanical ratios and parameters of battery pack as well as control by simulation. During simulation the transient operating process can be studied in details with the dynamic model in Matlab/Simulink. The control strategy can be optimized by running the simulation and monitoring the operation of each components： the operating area of internal combustion engine （ICE）, fuel consumption （energy consumption）, the power distribution, the torque and rotary speed of ICE and motor, the operating efficiency of motor, the aheration of battery state of charge （SOC）, current and voltage.

The Practical Design Aspects of Anti-aliasing Filters for the Multirate Analog-to-digital Processing in Microcontroller Embedded System

Due to the widespread computer technology, it is difficult to imagine a research or a control of any physical object without using a powerful hardware and software applications. To use digital technologies we need to collect data of a real world in digital system by the analog-to-digital converters. Taking into account the relative high computational capabilities of modern microcontrollers the article proposes a multirate processing system. The paper presents practical design aspects of the analog and digital anti-aliasing filter fbr the measurement path. having regarded the real possibilities and limitations of today＇s filters and analog-to-digital embedded converters.

The Design and Implementation of Virtual Physics Experiment System based on VB Programming

This paper used the virtual reality modeling language （VRML） to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual realization experiment platform, the interface has friendly interface, stable operation, strong practicability like with the Windows style, is a kind of reform for the traditional physics experiment teaching mode. The system has practical use value, also has reference value for the reform and modernization of other experimental courses.

Fluid dynamic modeling of a free piston engine with labyrinth seals

Preliminary design and simulation of a free piston engine suitable for small-scale energy production in distributed energy systems is presented in this paper.The properties,particularly the properties of gas seals of the engine are simulated using a simulation program developed for this case,and the results are utilized in preliminary main design parameter selection.The engine simulation program was developed by combining and modifying the source codes of the simulation and calculation programs obtained from Helsinki University of Technology,Tampere University of Technology,and Lappeenranta University of Technology.Because of the contact-free labyrinth seal used in the piston,the efficiency of the motor is lower than the efficiency of a conventional motor with oil lubricated piston rings.On the other hand,the lack of bearing losses,and the lack of losses associated with a crankshaft system and a gearbox,as well as the lack of lubrication oil expenses,compensates this effect.As a net result,this new motor would perform slightly better than the conventional one.Being completely oil-free,it is very environmentally friendly,and its exhaust gases are completely free of oil residuals which are causing problems in normal gas motors.