DEVELOPMENT OF COMPUTER SIMULATION SOFTWAREON PHASE TRANSFORMATION DURING QUENCHING

A computer software to simulate the phase transformation during quenching is designed based on Avrami equation and Scheil additivity principle of incubation period. The isothermal transformation diagrams of supercooled austenite are described by cubic spline functions. This software is possess of a good graphic interface of Windows style, can simulate the whole process in austenite decomposition during continuous cooling. If the cooling rate was given, the fraction of various microstructures transformed of austenite decomposition during continuous cooling at any temperature can be calculated. The simulation results are checked with the quenching experiment of 45 steel. The results indicate that the simulation results are comparatively close to the experimental results.

An integrated spatial planning of the mountainous landscapes for ski sports in a case area at the eastern Türkiye

Mountainous regions have disadvantages in economic development because of harsh physical and climatic conditions.However,winter tourism activities are one of the key components for supporting economic development in the highlands.Establishing a ski resort area supports direct and indirect employment in a region,and it stops immigration from mountainous regions to other places.This research aimed to assess the potential ski areas using a multi criteria evaluation technique in the Van region which is located in the eastern part of Türkiye.In this context,snow cover duration,sun effect,slope,slope length,elevation,population density,distance from main roads and lake visibility were used as input factors in the decision making process.Each factor was standardized using a fuzzy technique based on existing well-known ski centers in Türkiye.The weight of inputs was defined by applying a survey to the professional skiers.The most important factors were detected as transportation opportunities and snow covers whereas,the least important factors were elevation and population density.Additionally,lake visibility was very important to make a difference from other existing facilities in the region.Therefore,it was included as constraints and lake visible areas were extracted at the final stage of the research.Potential ski areas were mapped in three levels as professional,intermediate and beginner skiers.One of the suitable areas was selected as a sample projection and for the 3D simulation of the ski investment area.Potential costs and benefits were discussed.It was found that a ski tourism area investment can be amortized in 3 years in the region.

Research on the simulation system of the sports training

In recent years, with the continued progress of science and technology, as an aided tool for physical training, the computer plays a more and more important role in continuously penetrating the high-tech achievements in the sports. The computer simulation technology has been a breakthrough in the training, which has caused the attention of the majority of sports coaches and athletes. According to the analysis of each subject of the sports training, we find that the computer simulation technology has not fully obtained the popularization and application in many aspects of the sports, which is related to the development levels of the computer simulation technology. The simulation system designed in some directions is not practical, and some are still in the blank. Therefore the application of the simulation system in the sports training has a long way to go.

Application of 3-D numerical simulation software SRIFCAST to produce ductile iron castings

Based on a method using numerical simulation equations and their solution schemes for liquid metal flows andheat transfer during mold filling and the solidification process of casting, 3-D numerical simulation software SRIFCAST wascreated. This includes enmeshment of casting; velocity and temperature fields calculation; displaying iso-temperature lines;velocity vectors and 3-D temperature fields on a Windows 9x operating system. SRIFCAST was applied to produce soundcastings of automobile and diesel engines, and also to connect with microstructure simulation for ductile iron castings.

A Simulation Software for the Prediction of Thermal and Mechanical Properties of Wood Plastic Composites

Modelling and simulation has become an important tool in research and development. Simulation models are used to develop better understanding of the internal properties and impact of various parameters on the final quality of the product or process. Simulation model reduces the number of experiments and saves the wastage of material, time and money and are widely used in automobile industry, aircrafts manufacturing, process engineering, training for military, health care sector and many more. Wood Plastic Composite （WPC） is a bio-composite made by mixing wood fibers and plastic granules together at high temperature by compression molding or injection molding. A large quantity of WPC is rejected due to poor quality and low mechanical strength. There is a need to improve the understanding of the wood plastic composites, with both theoretical and experimental analysis. The impact of various parameters and processing conditions on the final product is not known to the industry people, due to less simulation models in this field. A new simulation software WPC Soft is developed to predict the mechanical and thermal properties of WPC. The software can predict the mechanical and thermal properties of WPC. The simulation results were validated with the experimental results and it was observed that the predicted values are quite close to the experimental values and with the further refining of the model, prediction can be further improved. The present simulation software can be easily used by the industry people and it requires very little knowledge of computers or modeling for its operation.

ANALYSIS OF METEOROLOGICAL CONDITIONS FOR THE BASE OF MARINE SPORTS IN THE 26TH SUMMER UNIVERSIADE IN SHENZHEN IN 2011

Based on the real-time wind direction and speed data from an automatic meteorological monitoring network in Shenzhen, the wind characteristics of Jue Diao Sha maritime area are analyzed. As indicated in the results, the wind speed of this area is higher than that over the land, the average wind speed is above 3 m/s and the probability for the maximum wind speed to drop below 20 m/s is above 90%. Moreover, the probability for the hourly swing angle of wind direction to become less than 50o is above 80%, suggesting that the wind conditions in the Jue Diao Sha area could meet the requirements of the sporting events. According to the numerical simulation, this area is the best selected site among three candidates. Furthermore, the characteristics of daily land and sea breezes are such that it is suggested the game will be best carried out from 1000 to 1700 Beijing Standard Time.

Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source

The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of biodeposition.Theoretically,biodeposition in cage culture areas without specific emission rules can be simplified as point source pollution.Fluent is a fluid simulation software that can simulate the dispersion of particulate matter simply and efficiently.Based on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid software.In the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling fluxes.At sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),respectively.The simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),respectively.There was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well simulated.Moreover,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative error.Thus,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition in the open waters can be simply and effectively simulated by the fluid simulation software Fluent.

基于Simulation X的多轴转向系统功能安全仿真分析

基于ISO 26262《道路车辆功能安全》的标准要求,对特种车的多轴电液转向系统进行分析,以提高系统的安全性和可靠性。运用Simulation X软件建立详细的多轴特种车仿真模型,通过模拟故障模式注入进行仿真试验。对仿真结果和数据进行分析,评估得到故障的严重性、暴露度和可控性,从而确定相应的汽车安全完整性等级。基于故障注入仿真的汽车功能安全分析方法,在系统早期设计阶段可以作为评估架构安全性的重要手段。

基于Computer Simulation Technology的磁共振射频线圈模拟与设计

目的:基于CST(Computer Simulation Technology)软件设计磁共振射频线圈,利用软件功能计算S参数、驻波比,求解每个网格的电场和磁场的方向、大小等,辅助完成实际线圈设计。方法:以单圈线圈为例,设计3层仿真模型:铜箔线圈层、环氧玻璃布层压板层、水模层。正确输入每一层的材料参数,并加入电容、端口等集总参数元件。设计合适的网格划分要求,插入场监视器。结果:数据结果包括一维结果和二、三维结果,其中一维结果包括S参数,驻波比,不连续端口的电流、电压、阻抗,集总参数元件的电流、电压、阻抗等,二、三维结果包括电场分布、磁场分布、表面电流等。从S11参数看出此线圈模型可在21.86 MHz处实现调谐和匹配,实际中可用作0.5 T磁共振成像设备的线圈。电磁场分布结果可以看出电容附近电场强度较高,磁场强度在线圈附近z方向强度较高。结论:磁共振射频线圈的设计可以利用CST软件辅助完成,通过调整线圈的形状、铜箔宽度等建立模型,根据S参数查看调谐匹配、耦合结果,通过场监视器的设置,查看二、三维电磁场分布。由结果再修改模型,最终完成设计。

Dynamic Simulation of Tracked Vehicle Using the DADS Software

The track model used in the dynamic analysis and design system software is investigated. A home made tank is taken as an example to illustrate the method for modeling an integral tracked vehicle and perform the dynamic simulation. The obtained results have demonstrated that the simulation method has the advantage of high efficiency, more convenience and more insight into the dynamical behavior of the system.

Computer Aided Simulation on Precision Cold Forging of Universal Joint Cross

The 3D FEM numerical simulation on multi-action precision cold forging technology of universal joint cross and differential spider is done in this article using DEFORM Software, a commercial computer aided engineering software specializing in forming and heat treatment simulation technology, and suitable for cold, warm and hot forging process. The material flow properties, the dynamic variation of stress and strain in the process of deformation and the load-stroke curve have also been achieved. A good consistency is exhibited between simulation results and practical data. Based on the DEFORM simulation results, the optimized procedure has been found for forging a universal joint cross. What should be emphasized here is that a better understanding of practical forging characters and the environmental factors can greatly improve the simulation accuracy thus make the simulation results more reliable.

On modeling approach for embedded real-time software simulation testing

Modeling technology has been introduced into software testing field. However, how to carry through the testing modeling effectively is still a difficulty. Based on combination of simulation modeling technology and embedded real-time software testing method, the process of simulation testing modeling is studied first. And then, the supporting environment of simulation testing modeling is put forward. Furthermore, an approach of embedded real-time software simulation testing modeling including modeling of cross-linked equipments of system under testing （SUT）, test case, testing scheduling, and testing system service is brought forward. Finally, the formalized description and execution system of testing models are given, with which we can realize real-time, closed loop, mad automated system testing for embedded real-time software.

Hierarchy-Based Team Software Process Simulation Model

According to the characteristic of Team Software Process （TSP）, it adopts a hierarchy-based model combined discrete event model with system dynamics model. This model represents TSP as form of two levels, the inner level embodies the continuity of the software process, the outer embodies the software development process by phases, and the structure and principle of the model is explained in detail, then formalization description of the model is offered. At last, an example is presented to demonstrate the simulation process and result. This model can simulate team software process from various angles, supervise and predict the software process. Also it can make the management of software development become more scientific and improve the quality of software.

Simulation of a Flexible Manufacturing System with AutoMod Software

A flexible manufacturing system (FMS) is a highly automated, complex system. Simulation is a well-proven method to design or analyze an FMS. Deployment of a radio frequency identification (RFID) system in FMS produces large volumes of RFID data streams, which provide valuable information to improve the operation of FMS. Different frameworks are presented in this paper regarding the use of RFID data streams in an FMS simulation. Simulations are performed with AutoMod software. Related technical details are also presented. The paper’s structure is complied as the following steps: step 1, the introduction of AMHS, FMS and AutoMod;step 2, FMS simulation using AutoMod software;step 3, simulation frameworks driven by RFID data streams;step 4, conclusion.

Component-based software reliability process simulation considering imperfect debugging

In view of the flaws of component-based software （CBS） reliability modeling and analysis, the low recognition degree of debugging process, too many assumptions and difficulties in obtaining the solution, a CBS reliability simulation process is presented incorporating the imperfect debugging and the limitation of debugging resources. Considering the effect of imperfect debugging on fault detec- tion and correction process, a CBS integration testing model is sketched by multi-queue muhichannel and finite server queuing model （MMFSQM）. Compared with the analytical method based on pa- rameters and other nonparametric approaches, the simulation approach can relax more of the usual reliability modeling assumptions and effectively expound integration testing process of CBS. Then, CBS reliability process simulation procedure is developed accordingly. The proposed simulation ap- proach is validated to be sound and effective by simulation experiment studies and analysis.

Modeling and Simulation of Skid-mounted LNG Plants Using HYSYS Software

This study presents three kinds of skid-mounted plants, including single mixed refrigerant cycle （MRC）, nitrogen expander cycle, and natural gas （NG） Claude cycle. Hysys simulation shows that single MRC is the most efficient cycle among the three. The specific power of single MRC liquefiers is 1 485 k.l/kg, 15% higher than that of large liquefaction process. Considering the recovery of stranded-gas, commercial analysis suggests that the initial cost of LNG plants ranging from 1 to 100 ms/day can be paid back in 2 to 4 years.

The Modern Information Technologies and Visualization Methods for Analysis of Computer Simulation Results for Complex Plasma

In this paper we present a software package based on modern information technologies that allows rapid analysis and visualization of the properties of complex plasmas.The properties of plasma are simulated by two means.First of all,we have applied the molecular dynamics simulation method which numerically solves the equations of motions for plasma particles.Secondly,we calculate microscopic properties of plasma by using the Boltzmann equation with additional relations,initial and boundary conditions.

Simulation-Based Evaluation for the Impact of Personnel Capability on Software Testing Performance

This study presents a decision making process in three steps of knowledge management for test organization using process simulation and financial analysis. First, project cost assessment of test knowledge management process subjects to different project duration and number of staffs. Two knowledge management simulation models representing experienced personnel with knowledge sharing and inexperienced personnel with internal training respectively are employed to contrast test personnel capability. Second, performance evaluation of software testing process by different personnel capability is conducted to simulate system test using three project metrics, namely, duration, effort cost, and quality. Third, a comparative financial analysis is prepared to determine the best solution by return on investment, payback period, and benefit cost ratio. The results from three stages of finding are discussed to arrive at the final scenario. We provide a case study evaluating how software testing industry needs to build effective test organization with high quality personnel for sustainable development and improvement.