染色工艺优化计算机辅助软件的设计与开发

针对染色过程工艺优化设计的问题,采用正交试验设计和多元回归分析方法,以主要影响因素为约束变量,以成本最小化为优化目标,构建染色过程数学模型,目的在于通过对工艺参数的定量分析提高工艺设计精度,缩短设计周期.在染色过程模型的基础上,以COM组件为媒介采用混合编程技术,将MATLAB与VC相结合,开发出染色工艺优化计算机辅助系统.该系统综合利用MATLAB成熟的遗传算法代码、算法良好的全局寻优性和寻优精度以及VC友好的界面开发能力,发挥了两者优点,既解决了工艺参数最优化问题,得到有效的可行性解,又充分提高了系统的开发效率和运算速度.实践证明,系统可实现原材料数据的显示、更新、保存以及工艺性能优化、成本和质量预估等功能,为工艺在线优化和智能控制提供条件,有效的降低生产成本、保证产品质量.除此之外,系统工作稳定,操作简单,数据直观,可广泛应用于各种复杂过程中的数据分析和工艺优化场合,具有很好的工程实用价值和推广价值.     

CAD系统的二次开发在飞机构型优化中的应用

飞机概念设计优化目前存在的主要问题是分析对象的几何描述过于简单、描述不统一和修改困难,造成分析计算可信度不高而且不同学科分析模块间信息很难转换。从建立一个三维运输机参数模型入手,通过CAD系统的二次开发,将模型集成到设计优化框架中,应用高信度的计算流体方法（CFD）,以飞机起飞重量最小为目标完成构型优化。     

Multidisciplinary design optimization of mechanisms

The optimization of mechanisms is usually done in the field of mechanism itself. As a result the structural safety of the mechanism is neglected. To ensure the safety and improve the dynamic characteristics of mechanisms, a multidisciplinary design optimization procedure is proposed in this paper to synthesize optimum mechanisms. Two disciplines are involved in the multidisciplinary design optimization. They are the mechanism and the structure. The multi-level decomposition approach is chosen to generate optimum mechanisms. The optimized mechanisms not only satisfy mechanism and structural constraints but also have optimum objective function values in the two disciplines. In order to solve general mechanism design problems two widely used commercial softwares MSC/NASTRAN and MSC/ADAMS are integrated in the procedure to do the structural and the mechanism analysis, respectively. When the structural optimization is performed, a compromised approach is introduced to treat multiple configurations of mechanisms during operation. Two mechanism design problems are given to test the proposed method.     

Multidisciplinary optimization of a transport aircraft wing using particle swarm optimization

The purpose of this paper is to demonstrate the application of particle swarm optimization to a realistic multidisciplinary optimization test problem. The papers new contributions to multidisciplinary optimization are the application of a new algorithm for dealing with the unique challenges associated with multidisciplinary optimization problems, and recommendations for the utilization of the algorithm in future multidisciplinary optimization applications. The selected example is a bi-level optimization problem that demonstrates severe numerical noise and has a combination of continuous and discrete design variables. The use of traditional gradient-based optimization algorithms is thus not practical. The numerical results presented indicate that the particle swarm optimization algorithm is able to reliably find the optimum design for the problem presented. The algorithm is capable of dealing with the unique challenges posed by multidisciplinary optimization, as well as the numerical noise and discrete variables present in the current example problem.     

An object-oriented program shell for integrating CAD software tools

The number of CAD programs and their capabilities have risen greatly in recent times. As well, the number of Application Programmer Interface (API) products and the number of representation standards for display, database storage and communication has also risen. These applications, API products and representation standards are generally not compatible except through specific, individually programmed interfaces. Incompatibility of API software products arises because of: (i) different representations for the same information, and (ii) different ways of communicating with the API products. This article describes the derivation of a generic software architecture to overcome the second source of incompatibility. The derivation employs the “box structure” (system engineering) software development methodology in a generic, high level manner; by considering activities performed with current CAD software, but without going into the details. The objective is to determine the types of software objects required and the types of messages that must be passed between them. The result is an architecture in which Tool objects embodying individual software tools are plugged into a Shell object which holds the Tool’s together as a single program, provides for interactions between Tool’s and controls when each Tool is active. In this way separately developed software tools can be combined seamlessly into a highly graphical and interactive environment.     

Rapidly finding CAD features using database optimization

Automatic feature recognition aids downstream processes such as engineering analysis and manufacturing planning. Not all features can be defined in advance; a declarative approach allows engineers to specify new features without having to design algorithms to find them. Naive translation of declarations leads to executable algorithms with high time complexity. Database queries are also expressed declaratively; there is a large literature on optimizing query plans for efficient execution of database queries. Our earlier work investigated applying such technology to feature recognition, using a testbed interfacing a database system (SQLite) to a CAD modeler (CADfix). Feature declarations were translated into SQL queries which are then executed.The current paper extends this approach, using the PostgreSQL database, and provides several new insights: (i) query optimization works quite differently in these two databases, (ii) with care, an approach to query translation can be devised that works well for both databases, and (iii) when finding various simple common features, linear time performance can be achieved with respect to model size, with acceptable times for real industrial models. Further results also show how (i) lazy evaluation can be used to reduce the work performed by the CAD modeler, and (ii) estimating the time taken to compute various geometric operations can further improve the query plan. Experimental results are presented to validate our main conclusions.     

Multidisciplinary design optimization on vehicle tailor rolled blank design

Tailor rolled blank (TRB) is an emerging steel rolling process to produce lightweight vehicle components. It allows continuous metal thickness changes, and as a result, it offers opportunities for automotive design in weight reduction, part complexity reduction, reduced capital investment, yet, maintains equal to or better strength characteristics. The objective of this research is to take advantages of the TRB manufacturing technology and combine with the advanced multidisciplinary design optimization (MDO) methodology to optimize vehicle structure. The process begins with noise vibration and harshness (NVH) optimization. The outputs of the optimal NVH response sensitivities are employed to build the first order response surface models. Uniform Latin Hypercube sampling and subset selection regression methods are used to construct the response surface models for the highly nonlinear impact and seatbelt pull responses. The optimal NVH design is then used as the starting point for MDO to obtain the optimal thickness profiles for the TRB parts. A vehicle application considering multiple impact modes, seatbelt pulls, and NVH, is used to demonstrate the proposed process for vehicle underbody TRB design. Results of this MDO TRB study is presented and discussed.     

Multidisciplinary design optimization of lumbar transpedicular screws

Some of the complications associated with the use of transpedicular screws for spinal fusions include the large diameters of the screws and screw breakagein vivo. Recent advances in multidisciplinary design optimization techniques have provided a unique approach to incorporate the structural, biological, and manufacturing disciplines involved in the design process of spinal screws, allowing the development of smaller and safer transpedicular screws.     

The OptdesX design optimization software

This paper describes the OptdesX design optimization software. The software provides a design environment for optimization of engineering problems. The software supports interactive variable and function selection, optimization with continuous and discrete algorithms, design space graphics, tolerance analysis, and control of noise in numerical derivatives, as well as numerous other features. The software is described and illustrated in terms of a small example problem. The software is available on Unix platforms only. Received December 30, 2000     

工控组态软件对外集成方式的研究与设计

介绍了组态软件对外集成的几种方式，以及Windows提供的支持这几种方式的DDE、OPC、ActiveX自动化等几种标准，通过这几种方式，可以实现程序间数据交换，方便对外集成，并在实际工程中应用涉及到的主要技术，取得了良好的效果。     

新涡桨飞机机头结构优化设计

在新涡桨支线飞机机头结构初始方案设计阶段,采用MSC Nastran对机头初始设计方案进行总体结构分析和尺寸优化,为机头结构选型和详细设计提供参考.     

Assessment techniques,database design and software facilities for thermodynamics and diffusion

The purpose of this article is to give a set of recommendations to producers of assessed thermodynamic data, who may be involved in either the critical evaluation of limited chemical systems or the creation and dissemination of larger thermodynamic databases. Also, it is hoped that reviewers and editors of scientific publications in this field will find some of the information useful. Good practice in the assessment process is essential, particularly as datasets from many different sources may be combined together into a single database. With this in mind, we highlight some problems that can arise during the assessment process and we propose a quality assurance procedure. It is worth mentioning at this point, that the provision of reliable assessed thermodynamic data relies heavily on the availability of high quality experimental information. The different software packages for thermodynamics and diffusion are described here only briefly.     

Redesigning, implementing and integrating Escherichia coli genome software tools with an object-oriented database system.

This paper reports our exploratory work to redesign, implement and integrate a collection of genome software tools with an object-oriented database system. Our software tools deal with genome data from Escherichia coli K-12, a bacterium that has been studied intensively and provides richer data sets than any other living organism. The object-oriented DBMS used for the integration is ONTOS, a commercial object-oriented system from Ontologic Inc. This redesign and implementation task was performed in two steps. First, C programs were converted into C++, and then the C++ version programs were modified and integrated with an object-oriented modeling of the data to form an ONTOS database application. The first step helps us develop a conceptual view for a DBMS-independent object-oriented construct. The second step elucidates what additional DBMS-dependent modification steps are needed to provide persistency to the objects. Examples are included to illustrate steps of the redesign and implementation. Overall, the outcome of this project demonstrates that programs and data can be successfully integrated with an object-oriented database, while providing the objects with persistency and shareability. This paper includes discussions using concrete examples on what advantage the object-oriented database approach provides over the relational database approach.     

多学科目标兼容优化算法及在MEMS中应用

针对复杂系统的优化设计问题,提出了面向非层级复杂系统的多学科目标兼容优化设计方法,对其基本思路、原理进行阐述。通过在系统级中建立兼容约束和在子系统中构造兼容目标,使各子系统在独立优化设计的同时满足各系统之间的耦合关系,并使系统得到总体的最优解。并将此算法应用于梳齿式微加速度计的设计中,验证了此方法的可行性。     

快递配送路径的优化研究与软件设计

中国的快递行业近几年来呈现出爆发式的增长,如何提高快递员的配送效率以及保障交通安全,已经成为一个亟需解决的重要课题。结合旅行商问题(TSP)在快递配送中的应用,采用C-W节约算法对快递配送路径进行了优化研究。用蒙特卡罗模拟后发现,C-W节约算法比快递员当前使用的最近邻居算法(NNH)更优,C-W节约算法找出的最佳路径平均缩短了7.8%的里程。借助高德地图API获取配送点之间的路径信息,采用C-W节约算法和Shiny R技术结合,开发了基于Internet的快递配送路径优化工具Delivery Helper。Shiny技术简化了网页开发过程,使用R语言就可以搭建动态交互的网页应用程序。快递公司或快递员只需登录软件网址就可使用Delivery Helper。该软件有望提高快递员的配送效率,减少快递员低头看手机的次数,从而保障交通安全。     

A hyper-heuristic approach to aircraft structural design optimization

The conceptual design of an aircraft is a challenging problem in which optimization can be of great importance to the quality of design generated. Mass optimization of the structural design of an aircraft aims to produce an airframe of minimal mass whilst maintaining satisfactory strength under various loading conditions due to flight and ground manoeuvres. Hyper-heuristic optimization is an evolving field of research wherein the optimization process is continuously adapted in order to provide greater improvements in the quality of the solution generated. The relative infancy of hyper-heuristic optimization has resulted in limited application within the field of aerospace design. This paper describes a framework for the mass optimization of the structural layout of an aircraft at the conceptual level of design employing a novel hyper-heuristic approach. This hyper-heuristic approach encourages solution space exploration, thus reducing the likelihood of premature convergence, and improves the feasibility of and convergence upon the best solution found. A case study is presented to illustrate the effects of hyper-heuristics on the problem for a large commercial aircraft. Resulting solutions were generated of considerably lighter mass than the baseline aircraft. A further improvement in solution quality was found with the use of the hyper-heuristics compared to that obtained without, albeit with a penalty on computation time.     

Multidisciplinary design optimization of a compact highly loaded fan

The recent progress in Multidisciplinary Design Optimization (MDO) enables engineers to revise design strategies and to address more complex problems. In this paper, the full design of a compact highly loaded fan for aerospace applications is considered. The design comprises several conflicting objectives, such as aerodynamic efficiency and structural integrity. Optimization techniques are applied at every stage of the design, leading to a reduced and accelerated overall process and an enlarged design space. Performance of the machine are first evaluated by through-flow modeling (low-fidelity radial distributions based on experimental correlations) to determine an optimal flow path configuration. High-fidelity aero-mechanical performances are then considered to generate the detailed design of the rotors, including section profiles along the span, as well as lean and sweep. The multi-objective algorithm enables one to consider simultaneously Computational Fluid Dynamics (CFD) and Computational Structural Mechanics (CSM). The methodology is applied to the design of a compact highly loaded fan achieving a 2.1 pressure ratio with an efficiency of 88 % while satisfying the mechanical constraint of titanium with a safety margin of 32 %. The proposed approach allows to generate an original configuration with a reduced time to market.     

Multidisciplinary design optimization of a small solid propellant launch vehicle using system sensitivity analysis

Multidisciplinary design optimization approaches have significant effects on aerospace vehicle design methodology. In designing next generation of space launch systems, MDO processes will face new and greater challenges. This study develops a system sensitivity analysis method to optimize multidisciplinary design of a two-stage small solid propellant launch vehicle. Suitable design variables, technological, and functional constraints are considered. Appropriate combinations of disciplines such as propulsion, weight, geometry, and trajectory simulation are used. A generalized sensitivity equation is developed and solved. These results are basis for optimization. Comparison of the developed approach with gradient optimization methods reveals that developed approach requires less computation time.