基于汽车轮罩软模开发的CAE模拟优化

在汽车研发过程中,为验证零件设计的制造可行性,装配焊接工艺的合理性,需进行样车试制,以提前发现问题,并在设计阶段将问题解决。软模开发能在短时间内,开发出成本低的零件,工艺及模具结构简单。但在模具调试时,容易出现开裂、起皱、甚至叠料缺陷。以某汽车轮罩为例,将CAE模拟分析技术引入软模开发中,缩短了调试时间,降低了修模成本,满足了软模开发的需要。

车身软模开发流程及日韩软模开发技术对比

首先介绍了汽车车身软模开发流程,然后从数据管理、二级供应商数量、零件制造工艺以及开发过程控制等方面,对日本与韩国的软模开发方式进行比对。日本与韩国软模开发方式存在较大差别,各自具有其优劣性,需择其优而取之。对国内汽车车身软模开发供应商提高软模开发能力有着重要指导作用。

基于Autoform仿真的前轮罩软模开发工艺优化

介绍了Autoform的功能及汽车覆盖件软模开发特点,研究了某汽车前轮罩的软模开发。利用数值仿真软件Autoform,实现了模具设计与冲压工艺的CAE仿真,并预测可能出现的缺陷。根据仿真结果对模具与工艺修改后再次进行CAE仿真优化,然后进行了冲压验证。试冲结果与仿真分析结果基本一致,零件质量基本满足交样要求。

激光切割技术在软模件上的应用

软模开发的零部件激光切割在汽车上的应用非常广泛。软模件激光切割是软模件加工的重要工序,在软模件激光切割中经常发生尺寸不合格、回弹影响切割尺寸精度,甚至激光切割经常出现废品等问题。激光切割技术可解决这些影响成本、周期的关键问题。从激光切割的原理、软模件切割参数以及软模件切割尺寸精度控制等方面叙述了激光切割对软模件尺寸精度的重要性。

SDG-based Model Validation in Chemical Process Simulation

Signed direct graph (SDG) theory provides algorithms and methods that can be applied directly to chemical process modeling and analysis to validate simulation models, and is a basis for the development of a software environment that can automate the validation activity. This paper is concentrated on the pretreatment of the model validation. We use the validation scenarios and standard sequences generated by well-established SDG model to validate the trends fitted from the simulation model. The results are helpful to find potential problems, assess possible bugs in the simulation model and solve the problem effectively. A case study on a simulation model of boiler is presented to demonstrate the effectiveness of this method.

（Dis）Economies of Scale in Business Software Systems Development and Enhancement Projects

In the software engineering literature, it is commonly believed that economies of scale do not occur in case of software Development and Enhancement Projects （D＆EP）. Their per-unit cost does not decrease but increase with the growth of such projects product size. Thus this is diseconomies of scale that occur in them. The significance of this phenomenon results from the fact that it is commonly considered to be one of the fundamental objective causes of their low effectiveness. This is of particular significance with regard to Business Software Systems （BSS） D＆EP characterized by exceptionally low effectiveness comparing to other software D＆EP. Thus the paper aims at answering the following two questions： （1） Do economies of scale really not occur in BSS D＆EP？ （2） If economies of scale may occur in BSS D＆EP, what factors are then promoting them？ These issues classify into economics problems of software engineering research and practice.

Software development of modeling assistant for continuous suspension bridges with multi-pylon

Building a reasonable and accurate finite element model is the first and critical step for structural analysis of complicated bridge. In this article, modeling assistant for continuous suspension with multi-pylon is developed based on .Net platform, with VB.Net, C# language and OpenGL graphic technique. With parameterized modeling method, finite element model of this kind of bridge can be built quickly and accurately, and multi-type element modeling with uniform parameters is realized. With advanced graphic technique, three-dimensional model graph can be real-timely previewed for intuitive data check. With an example of practice project, the accuracy and feasibility of this modeling method and practicality of this software are verified.

A UML profile for framework modeling

The current standard Unified Modeling Language(UML) could not model framework flexibility and extendibility adequately due to lack of appropriate constructs to distinguish framework hot-spots from kernel elements. A new UML profile that may customize UML for framework modeling was presented using the extension mechanisms of UML, providing a group of UML extensions to meet the needs of framework modeling. In this profile, the extended class diagrams and sequence diagrams were defined to straightforwardly identify the hot-spots and describe their instantiation restrictions. A transformation model based on design patterns was also put forward, such that the profile based framework design diagrams could be automatically mapped to the corresponding implementation diagrams. It was proved that the presented profile makes framework modeling more straightforwardly and therefore easier to understand and instantiate.

Development and Application of Heat-integrated Aromatics Fractionation Process

The PRO/Ⅱ process simulation software was applied to carry out simulated calculation of the aromatics fractionation unit and the heat integrated rectification process was proposed for the aromatics fractionation section of the 1.0 Mt/a toluene disproportionation unit at the Zhenhai Refining and Chemical Company. The optimized operating parameters were obtained through the energy utilization analysis,process simulation,heat exchanger calculations and comparisons of utility consumption. The operation of commercialized unit has revealed that the design parameters of each rectification column were consistent with the operation results,and the utility consumption was about 47% lower than the traditional heat integrated process.

Analysis and application in controlling surrounding rock of support reinforced roadway in gob-side entry with fully mechanized mining

In order to optimize gob-side entry in fully-mechanized working face in moderate-thick-coal seams, we adopt a new attempt to pack roadside by pumping ordinary concrete, which is very important for the development of gob-side entry technology. The concrete has a long initial setting time and a low initial strength. So it is difficult to control the surrounding rock. In this paper, we analyze the effect of using roadside cable to reinforce supporting in gob-side entry surrounding rock controlling based on elas-tic-plastic and material mechanics knowledge. And then we propose a scheme that cable is used to reinforce roadside supporting and a single hydraulic prop is used as the temporary supporting in gob side. Using the numerical simulation software FLAC2D, we numerically simulated supporting scheme. Results of both the 2D modeling and the industrial test on No.3117 face in Jingang Mine prove that the scheme is feasible. The results show that the technology of protecting the roadway in gob-entry retained efficiently make up the deficiency of roadside packing with ordinary concrete, effectively control the roof strata and acquire a good result of retaining roadway.

Enterprise modeling method of calculation-independent model level

Aimed at deficiencies in the development and implementation of Enterprise Service Architecture （ESA） software, an ESA software developing mode based on Model Driven Architecture （MDA） is put forward. This mode includes a calculation-independent model （ CIM ）, a platform-independent model （ PIM ）, a platform-specific model （PSM） and a code level. Based on this mode, the modeling architecture of CIM level is presented. CIM here includes a global model, a process model, an information model and an organization model. The modeling elements of global model, process recta-model, information recta-model and organization meta-model are defined in detail and the relationship between them is described. The reflecting relationship between these models is established as well.

Measuring Effectiveness of COCOMO I and COCOMO II Using a Case Study

There are several software estimation models such as Line of Code, Function Point and COnstructive COst MOdel （COCOMO）. The original COCOMO model is one of the most widely practiced and popular among the software development community because of its flexible usage. It is a suite of models i.e., COnstructive Cost MOdel I and COnstructive Cost MOdel II. in this paper, we are evaluating the both models, to find out the level of efficiency they present and how they can be tailored to the needs of modem software development projects. We are applying COCOMO models on a case study of an e-commerce application that is built using Hyper Text Markup Language （HTML） and JavaScript. We will also shed light on the different components of each model, and how their Cost Drivers effect on the accuracy of cost estimations for software development projects.

The Development of Intelligent Home Remote Monitoring System based on B/S Framework

This paper deeply studies the intelligent Home embedded system based on B/S architecture. Firstly, analysis requirement of Home function based on the existing software development mode, and proposed a system framework of intelligent Home system, and designed the communication scheme of the whole Home system, also gives the system each function module realization. This paper achieve two basic service system based on Intelligent Home through a series of analysis and design： outdoor remote intelligent Home monitoring service and the indoor intelligent management service.

Virtual Dressing Room Application with Virtual Human Using Kinect Sensor

This study proposes a real time 3D virtual model controll and a virtual dressing room application to enable users to try virtual garments and shoes on in front of a virtual mirror. A virtual representation of the user appears in a virtual changing room and the user＇s hand motions select the clothes from a list on the screen. Afterwards, the selected virtual clothes appear on a humanoid model in the virtual mirror. For the purpose of aligning the 3D garments and shoes with the model, 3D locations of the joints are used for positioning, scaling and rotating. By using our developed algorithm, small, medium, large or xlarge garment size is selected automatically and this information is shown on the screen. Then, we apply skin color detection to handle the unwanted occlusions between the user and the model. To create a more realistic effect, the system takes into account different images of the clothes according to different human poses and movements. Optional mirror selection buttons make it possible to have multiple viewing angles on the model. Additionally, we developed an algorithm for matching up all motions between the model and garments. In this study, we benefit from the Microsoft Kinect SDK （software development kit） in order to follow the user＇s movements, coordinate the suitable clothe try-ons and provide depth sort effect to the human body and clothes. In order to use the rapid calculation attributes of game engines, we used unity 3D game engine.

Aspect-Oriented Design Method for Embedded Systems Based on Timed Statecharts

The formal modelling and verification method has become an effective way of improving the reliability and correctness of complex,safety-critical embedded systems.Statecharts are widely used to formally model embedded applications,but they do not realise the reasonable separation of system concerns,which would result in code scattering and tangling.Aspect-Oriented Software Development(AOSD)technology could separate crosscutting concerns from core concerns and identify potential problems in the early phase of the software development life cycle.Therefore,the paper proposes aspect-oriented timed statecharts(extended timed statecharts with AOSD)to separately model base functional requirements and other requirements(e.g.,scheduling,error handling),thereby improving the modularity and development efficiency of embedded systems.Furthermore,the dynamic behaviours of embedded systems are simulated and analysed to determine whether the model satisfies certain properties(e.g.,liveness,safety)described by computation tree logic formulae.Finally,a given case demonstrates some desired properties processed with respect to the aspect-oriented timed statecharts model.

Research on software development of air temperature prediction in coal face

With ever-increasing depth of coal mine and the continuous improvement of mechanization, heat damage has become one of the major disasters in coal mine exploitation. Established the temperature prediction models suitable for different kinds of tunnels through analysis of the heat of shafts, roadways and working faces. The average annual air temperature prediction equation from the inlets of shafts to the working faces was derived. The formula was deduced using combine method of iteration and direct calculation. The method can improve the precision of air temperature prediction, so we could establish the whole pathway air temperature prediction model with high precision. Emphasizing on the effects of leakage air to air temperature of working face and using the ideology of the finite difference method and considering the differential equation of inlet and outlet at different stages, this method can significantly improve the accuracy of temperature prediction. Program development uses Visual Basic 6.0 Language, and the Origin software was used to fit the relevant data. The predicted results shows that the air temperature generally tends to rapidly increase in the air inlet, then changes slowly on working face, and finally increases sharply in air outlet in the condition of goaf air leakage. The condition is in general consistent with the air temperature change tendency of working face with U-type ventilation system. The software can provide reliable scientific basis for reasonable ventilation, cooling measures and management of coal mine thermal hazards.

Question of the status quo and countermeasure exit in the China Business Network Marketing

In the application process of the Internet and network marketing, many Chinese companies are actively engaged in practice, and after an exploratory period of time, companies accumulated some experience in a representative model. Such as： Chinese companies have a combination with traditional marketing and purchase advanced software model and then implemented through secondary development, they also change management ideas and systems, etc. These experiences and models can provide an effective and common reference for enterprise＇ s development of China＇ s e-commerce.

Development and Application of Thermal Mathematical Model of Iron Ore Pellet Bed in Grate

Based on the analysis of heat transfer mechanics,physical and chemical change of pellet drying and preheating process in grate,the mathematical model is established and solved by three-diagonal matrix algorithm. With Visual Basic 6.0 a simulation software is developed.The model is verified by measurements at a domestic pellet plant,and the temperature distribution of pellet bed is gained.Meanwhile,the influence of different operation parameters on the pellet thermal process is studied.The results can be taken as a basis of practical production control and the grate optimizing design.

Towards automated software model checking using graph transformation systems and Bogor

Graph transformation systems have become a general formal modeling language to describe many models in software development process.Behavioral modeling of dynamic systems and model-to-model transformations are only a few examples in which graphs have been used to software development.But even the perfect graph transformation system must be equipped with automated analysis capabilities to let users understand whether such a formal specification fulfills their requirements.In this paper,we present a new solution to verify graph transformation systems using the Bogor model checker.The attributed graph grammars(AGG)-like graph transformation systems are translated to Bandera intermediate representation(BIR),the input language of Bogor,and Bogor verifies the model against some interesting properties defined by combining linear temporal logic(LTL) and special-purpose graph rules.Experimental results are encouraging,showing that in most cases our solution improves existing approaches in terms of both performance and expressiveness.

An effective fault prediction model developed using an extreme learning machine with various kernel methods

System analysts often use software fault prediction models to identify fault-prone modules during the design phase of the software development life cycle. The models help predict faulty modules based on the software metrics that are input to the models. In this study, we consider 20 types of metrics to develop a model using an extreme learning machine associated with various kernel methods. We evaluate the effectiveness of the mode using a proposed framework based on the cost and efficiency in the testing phases. The evaluation process is carried out by considering case studies for 30 object-oriented software systems. Experimental results demonstrate that the application of a fault prediction model is suitable for projects with the percentage of faulty classes below a certain threshold, which depends on the efficiency of fault identification(low: 47.28%; median: 39.24%; high: 25.72%). We consider nine feature selection techniques to remove the irrelevant metrics and to select the best set of source code metrics for fault prediction.