混流装配线计划调度系统设计与开发

随着全球市场竞争更加激烈，上层计划管理系统（MRPII/ERP）受市场影响越来越大，计划的适应性问题愈来愈突出，明显感到计划跟不上变化。因此，解决生产计划的适应性以及增加底层生产过程的信息流动，提高计划的实时性和灵活性，已经成为一个重要的研究课题。制造执行系统（MES），作为上层计划和底层控制的桥梁，能够通过传递信息，可使得从订单下达到产品完成的整个生产活动进行优化。依赖准确的数据对工厂活动进行指导、启动、响应和报告。其中，车间级计划与调度管理系统是整个MES系统的核心技术，是现代生产管理的关键问题之一。国内外许多学者对计划调度方法作了大量的研究。 在研究生期间参与了课题组国家863高技术计划项目“面向汽车行业总装过程的可视化监控与执行管理系统”的研究与开发工作，我的主要工作是：以西安法士特齿轮有限公司的装配制造执行系统项目为应用背景，在搭建课题主要内容的SIA-MES运行平台中承担生产事件模型的设计以及软件开发工作，并在SIA-MES运行平台基础上，对混流装配线的调度问题进行了研究，给出了一种缩短生产周期的投产排序算法，设计了混流装配线计划调度系统，独立完成了软件部分的设计与开发工作。并且通过了辽宁省电子信息产品监督检验院的产品测试、得到了他们的认证。 本文的内容主要有以下几方面： 首先，阐述了MES以及制造业混流生产的产生原因及发展现状； 其次，对SIA-MES运行平台做了简单的介绍；并重点阐述了平台基于事件触发的通信机制以及事件对于计划调度系统的支撑。在此基础上，分析制定了计划调度系统的设计目标，而后按此目标完成了系统的功能设计，并对混流装配线调度问题进行了研究，针对计划实施的不同阶段给出不同的优化方法。 最后，介绍了计划调度系统的软件实现。包括基于SOA的软件实现技术，给出了软件系统的总体结构，并对各模块的具体实现进行了简单的介绍，包括类设计以及数据库设计。

柔性托辊自动装配线及产品在线检测的研究与实现

托辊在国民经济的各行各业扮演着十分重要的角色，尤其在矿业生产的输送过程中,托辊更是发挥着巨大的作用。本项目旨在为托辊的自动化装配线提供整套控制执行系统。本文根据沈阳机床集团所提出的装配线控制要求，在查阅大量相关文献基础上，分析了托辊装配的整个工艺过程，结合先进制造的理念和技术，研究设计出包括制造过程底层信息系统在内的装配线控制系统。本文主要完成了以下研究工作及相关的创新性成果： 系统的供配电设计。根据设备的配电要求及相关规范，对整套控制系统的供配电进行合理的设计。 整条装配线的协调控制及信息系统设计与实现。结合目前广泛采用的工业现场总线技术，设计了整套分层控制及信息系统。整套系统分为三层，在顶层设计有监控系统，该系统通过以太网与下层的单台机床控制器进行信息互换。通过OPC技术将底层控制器采集到的现场信息在上位机上以友好的图文界面显示出来，供操作人员监控。同时还将每台机床的相关信息及以往报警历史按时间进行归档，形成现场装配过程信息备份，供上层的分析与决策系统使用。 现场每台机床采用独立的现场控制器进行控制。因为整条装配线被设计定位为柔性装配线，所以在机床控制上采用了伺服控制技术，以实现针对不同装配产品型号对托辊的支撑及夹具进行准确定位。控制器采用集逻辑、工艺、伺服控制于一体的西门子SIMOTION控制器。该控制器完成整个机床的动作及工艺控制，同时在现场每台机床控制器都配备一个触摸屏作为现场级人机界面，供机床现场调试和人机交互之用。 论文从整体上阐述了装配线控制系统的整体架构，并结合在线检测机床对机床的控制进行了讨论，从多方面体现出该控制及信息系统的完整性和先进性。 该项目开发的托辊装配线控制及信息系统旨在实现托辊安全、快速地自动化装配。并以单台机床单元控制器为主体通过现场总线技术为上层信息管理系统提供信息接口，为整条线的管理功能智能化扩展提供一个良好的平台。

Electron microscopic examination of the viromatrix of Rana grylio virus in a fish cell line

Rana grylio virus (RGV), a Ranavirus belonging to the family Iridoviridae, assembles in the viromatrix which is a factory for viral genome replication and particle assembly. Ultrastructural studies of the viromatrix will clarify the pathway of assembly. The viromatrix and quantitative changes in RGV infected epithelipma papulosum cyprini (EPC) cells, one of fish cell lines, were studied by electron microscopy. It was shown that viromatrices were adjacent to the nucleus, and the electron density was lower than that of the surrounding cytoplasm. The viromatrix contained virus particles with different forms, electron-dense materials and amorphous structures which included tubules and membranous materials. Tubules were often observed in direct continuity with empty capsids. Several bundles of intermediate filaments were seen alongside the viromatrix and crystalline aggregates. Large clusters of mitochondria occurred in proximity to viromatrix. A total of 990 cells profiles were examined. The results showed that 394 cells contained viromatrix: 89.3% contained one, and 10.7% contained two to four viromatrices. The number of viromatrices increased gradually and reached a peak at 16 h p.i. The viromatrix area at 24 h p.i. increased up to 7.4 +/- 0.69 mu m(2) which was three-times lower than that at 6 h p.i. The number of empty capsids within viromatrix was generally more than that of "full" particles at different time points, and there was a strong positive correlation between them. (c) 2005 Elsevier B.V. All rights reserved.

Studies on morphogenesis and cellular interactions of Rana grylio virus in an infected fish cell line

A pathogenic virus (RGV), isolated from diseased pig frog Rana grylio with lethal syndrome, was investigated with regard to morphogenesis and cellular interactions in EPC cells, a cell Line from fish. Different stages of virus amplification, maturation and assembly were observed at nucleus, cytoplasm and cellular membranes. The matured virus particles, were not only distributed diffusely in nucleus, cytoplasm and cellular surface, but also aggregated as pseudocrystalline arrays in the cytoplasm. Virions were released by budding from the plasma membranes, or following cell lysis. Various types of cell damage, such as small vacuoles, spherical inclusions, and swollen and empty mitochondria, were also found. Some typical characteristics of RGV, such as the symmetrical shape of the virions, replication process involving both nuclear and cytoplasmic phases, budding release from cellular membrane and intracellular membrane, viromatrix and paracrystalline aggregation in cytoplasm, and its acute pathogenic effects, were observed to be similar to that of other iridoviruses. Therefore, the RGV appears to be a member of the Iridoviridae based on these studies. (C) 1999 Elsevier Science B.V. All rights reserved.

Application of ICA in on-line verification of the phase difference of the current sensor

The performance of the current sensor in power equipment may become worse affected by the environment. In this paper, based on ICA, we propose a method for on-line verification of the phase difference of the current sensor. However, not all source components are mutually independent in our application. In order to get an exact result, we have proposed a relative likelihood index to choose an optimal result from different runs. The index is based on the maximum likelihood evaluation theory and the independent subspace analysis. The feasibility of our method has been confirmed by experimental results.

Effect of Solvent Molecular Size on the Self-Assembly of Amphiphilic Diblock Copolymer in Selective Solvent

Real-space self-consistent field theory (SCFT) is employed to study the effect of solvent molecular size on the self-assembly of amphiphilic diblock copolymer in selective solvent. The phase diagrams in wide ranges of interaction parameters and solvent molecular size were obtained in present study. The results indicate that the solvent molecular size is a key factor that determines the self-assembly of amphiphilic diblock copolymer. The self-assembled morphology changes from circle-like micelle to line-like micelle, then to loop-like micelle by decreasing the solvent molecular size in a wide range of solvent selectivity. We analyze and discuss this change in terms of the solvent solubility and the entropy contribution.

Pressure Controlled Self-Assembly of High Quality Three-Dimensional Colloidal Photonic Crystals

A concise pressure controlled isothermal heating vertical deposition (PCIHVD) method is developed, which provides an optimal growing condition with better stability and reproducibility for fabricating photonic crystals (PCs) without the limitation of colloidal sphere materials and sizes. High quality PCs are fabricated with PCIHVD from polystyrene spheres with diameters ranging from 200 nm to 1 mu m. The deep photonic band gap and steep photonic band edge of the samples are most favorable for realizing ultrafast optical devices, photonic chips, and communications. This method makes a meaningful advance in the quality and diversity of PCs and greatly promotes their wide applications.

On-line observation of interlaminar damage by ultrasonic inspection

This paper explores an on-line experimental method to highlight the process of internal damage development in composites by taking advantage of ultrasonic inspection. A loading device, which can work together with an ultrasonic inspection system, was designed, and the interlaminar shear damage of a double-sided grooved specimen of composite was examined on-line with the system. A full view of the progressive internal interlaminar damage, seen only with difficulty by common inspection methods, was successfully achieved.

Asymptotic analysis based on K-S constitutive law for a rubber wedge compressed by a line load at its tip

In the present paper, a rubber wedge compressed by a line load at its tip is asymptotically analyzed using a special constitutive law proposed by Knowles and Sternberg (K-S elastic law) [J. Elasticity 3 (1973) 67]. The method of dividing sectors proposed by Gao [Theoret. Appl. Fract, Mech. 14 (1990) 219] is used. Domain near the wedge tip can be divided into one expanding sector and two narrowing sectors. Asymptotic equations of the strain-stress field near the wedge tip are derived and solved numerically. The deformation pattern near a wedge tip is completely revealed. A special case. i.e. a half space compressed by a line load is solved while the wedge angle is pi.

An In-Situ Observation On Initial Aggregation Process Of Colloidal Particles Near Three-Phase Contact Line Of Air, Water And Vertical Substrate

The self-assembling process near the three-phase contact line of air, water and vertical substrate is widely used to produce various kinds of nanostructured materials and devices. We perform an in-situ observation on the self-assembling process in the vicinity of the three phase contact line. Three kinds of aggregations, i.e. particle-particle aggregation, particle-chain aggregation and chain-chain aggregation, in the initial stage of vertical deposition process are revealed by our experiments. It is found that the particle particle aggregation and the particle-chain aggregation can be qualitatively explained by the theory of the capillary immersion force and mirror image force, while the chain-chain aggregation leaves an opening question for the further studies. The present study may provide more deep insight into the self-assembling process of colloidal particles.

Tuning The Geometrical Parameters Of Biomimetic Fibrillar Structures To Enhance Adhesion

Fibrillar structures are common features on the feet of many animals, such as geckos, spiders and flies. Theoretical analyses often use periodical array to simulate the assembly, and each fibril is assumed to be of equal load sharing (ELS). On the other hand, studies on a single fibril show that the adhesive interface is flaw insensitive when the size of the fibril is not larger than a critical one. In this paper, the Dugdale Barenblatt model has been used to study the conditions of ELS and how to enhance adhesion by tuning the geometrical parameters in fibrillar structures. Different configurations in an array of fibres are considered, such as line array, square and hexagonal patterns. It is found that in order to satisfy flaw-insensitivity and ELS conditions, the number of fibrils and the pull-off force of the fibrillar interface depend significantly on the fibre separation, the interface interacting energy, the effective range of cohesive interaction and the radius of fibrils. Proper tuning of the geometrical parameters will enhance the pull-off force of the fibrillar structures. This study may suggest possible methods to design strong adhesion devices for engineering applications.