The increasing complexitiy of new and innovative products and the participation of specialists from different specific fields leads to a strong integration of design and engineering tasks．Supporting this complex interdepartmental cooperation by efficient and flexible information technologies is strongly required．A promising solution assumes a field or product-specific classification of simulation／calculation ressourees and knowledge in centers of competence and making it available in an integrated environment for collaborative engineering．

In the engineering industry，especially in the heavy engineering industry，there are notable economic benefits in the interference fit．Traditional computing method is not only too complicated，but also does not give objective appraisal of reliability for the interference fit．Therefore，the quality of interference fit is not high，and its application is restricted．The reliability for the interference fit is analyzed and it’s optimization is studied by reliability theory and optimization technique，the mathematical model is derived，the corresponding computer programs are worked out．Using the method and the programs not only can calculate reliability of interference fit，but can notably raise it by optim ization for interference quantity．

In order to design cooling systems for transmission systems of vehicles accurately，a weighting mean heat balance calculation method based on the heat generation statistics of use frequency of every gear mode was presented here．Temperature fields of a gear shifting box were studied numerically to illustrate the whole process from heat generation to heat flux and then to heat balance inside the gear shifting box．The improved heat balance calculation can demonstrate the average heating condition of transmission system of a vehicle in road environments more rationally，thus，it provides an optimal way to design cooling systems for transmission systems．And the calculation of heat generation of every gear mode is the application base of the new thermal
design method for transmission systems．

From the analysis of automobile vibration sources and the human responses to vibration，a mechanic dynamics model of man- chair- vehicle system with 13 degrees of freedom is built by simulating technology．Using the random vibration theory，the calculating methods are developed for parameters，including vibration pattern，transfer function，wheel transient load，and acceleration of seat rank parameter．With available data of motor，and the simulation calculating results about vibration characteristics are given as follows：the engine，the stiffness of wheel tire and damping of the automobile shock absorber have not much effect on the vibration of the seat；vertical stiffness of back row seat has much effect on the vertical vibration as it gets larger；the stiffness and damping of back shock absorber have much effect on the vibration of back row seat；the greater the stiffness of wheel tire is，the more the vibration increases；the stiffness of back shock absorber has some effect on the automobile ride quality．As the stiffness of back shock absorber decreases，the vertical acceleration of the back row seat decreases．With this simulation software，automobile ride quality can be predicted or evaluated．

The good control performance can not be gotten for a kind of complicated control system only using simple fuzzy controller．A integrated intelligent expert fuzzy controller is cornposed by introducing expert knowledge into the fuzzy controller．Then，fuzzy membership function can be optimized automatically according to the genetic algorithm (GA)encoded by matrix individual for direction to the parameters of membership function．The control performance is
largely improved．It enhanced adaptability for environment and parameter movement by introducing expert knowledge into the system ．

With special mechanical properties，honeycomb is applied to more and more areas．Using ABAQUS script interface，several programs were developed to build geometrical model of cellular material．The modeling efficiency is improved and the difficulty in the modeling for the complicated honeycomb is solved．

PC control procedure design and program using SFC，one of the standard program language of PLC，was introduced，the feasibility and merits of PC control procedure design and program using SFC were analyzed．The solution to wait problem in PC control procedure using SFC was advanced．The feasibility of PC control procedure design and programusing SFC is proved through practice．The efficiency and effectiveness of programming are improved greatly．

Floppy disk driver is the most popular peripheral storage device with many merits．But the storage devices nOW only apply to the standard com puter system ，which lim its the application in the em bedded system using single chip as the core，such as com puterised em broidery m achine．In practice，floppy disk driver is used as expansion of external storage．This paper gives a brief introduction to the control chip-GM 82C765B．based on which the hardware circuit design of interface between M CU and floppy disk driver，and the software design of the writing and reading of the floppy disk driver are provided．This design has been applied in the computerised embroidery machine and has achieved a real good effect．

Based on the requirements of adjustment mechanisms of a space solar telescope’s foci，a scheme of the mechanism is proposed．The design principle is illustrated in the article．The movement of the image lens is controlled by the step motor and screw．A model is made according to the design method proposed．The error analysis of the mechanism is also proposed．The struttural analysis of the mechanism under launch environment is given．

According to analyzing strained condition of surperhigh pressure cylinder，the transformation rules of stress-strain are deduced while it is effected by compound load．Some factors of its natural life andintension are pointed out．The method of calculating and the principle of designing are summarised．

The heat transfer coefficient of large rotary disc dryer was calculated by using particle transfer model of moving heating-plane type．Under the assumption of total mixture of the particle bed，the heat transfer coefficient of the every segment and the whole dryer was calculated by dividing the dryer into 55 segments according to the drying process．The strength model of the major bearing parts of the rotor system was also introduced．The results conformed to the fact of the operation of the dryer．

Coal’s caloric value is an important criterion in analyzing coal’S quality．In order to intuitively and accurately measure coal’S caloric value，a controlling system was realized based on microcom puter．Four-wire connection way was applied for circuit of measuring tem perature in controlling system ，and the temperature signal was gathered and transformed through PCL一816H A／D card．By experiment，the caloric value gotten had only 1．5 percent error compared with standard caloric value．Result show that the controlling system can satisfy the need for measuring coal’s caloric value，and provide a reference for other industrial measure．

The shape of old crotch scars on tree trunks was investigated，and the effects of hole shape on the mechanical strength of the plates with a hole were analyzed with a finite element software ANSYS．The Mises stress is used to evaluate the strength of the plates with a hole．Resuits dem onstrate that the elliptical hole，which elliptical parameter is larger than 2，has the best mechanical performance，as the plate is under uniform load in one direction．Also，results show that the circular hole has the best performance is the best one，as the ratio of the uniform loads in two directions is 0.5— 2.0．

Fuzzy comprehensive judgment is a new method of type selection design of the computer network structure．This article expounds some principles and methods of type selection design of the com puter network structure． As a practical case，this article rem arks in detail the process of the type selection design of the computer network structure of Xuzhou Construction Machinery roup Co．，Ltd．By using this judgment，the authors could gather those suggestions from several relative experts together to measure every plan of the network structure fairly and truly from very aspect．Thus，it will have high correctness and coordination and could be used in a wide field．