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101.
云制造技术给制造企业带来机遇的同时,也为其制造执行系统MES的设计与实现带来了新的挑战。为了解决单件小批MES中作业计划与调度优化问题,首先设计了一个从作业计划静态制定,到作业执行情况实时监控与主动感知,再到异常事件智能响应,最后到作业调度动态调节的闭环体系结构。接着针对异常信息实时获取与异常事件发现、异常事件智能化处理以及作业计划与调度优化算法计算能力服务化三个子问题,依次进行了问题分析并给出了技术解决方案。最后,以哈尔滨电机厂为案例对象,综合利用IEC/ISO 62264标准、大数据分析与挖掘方法以及由虚拟化、服务化和SOA等组成的云计算技术实现了单件小批MES作业计划与调度综合优化系统,验证了上述理论与方法的有效性。  相似文献   
102.
High‐brightness GaN‐based emissive microdisplays can be fabricated with different approaches that are listed and described. They consist either of hybridizing a GaN LED array on a CMOS circuit or building a monolithic component on a single substrate. Using the hybridization approach, two types of 10‐μm pixel pitch GaN microdisplay prototypes were developed: (1) directly driven, 300 × 252 pixels and (2) active‐matrix, 873 × 500 pixels. Brightness as high as 1 × 106 and 1 × 107 cd/m2 for blue and green arrays, respectively, were reached. GaN‐based emissive microdisplays are suitable for augmented reality systems or head‐up displays, but some challenges remain before they can be put in production.  相似文献   
103.
随着城镇化进程加快,国家加大基础设施建设投入,项目型制造业发展势头迅猛,而适应个性化需求、解决客户最终目标为导向的EPC模式(设计、采购、生产、建造、安装、维护和服务一揽子解决方案)已成为一种新型的项目型制造模式;而国内项目制造业的数字化制造水平与发达国家的差距还十分显著,尚未走出传统工业的大量消耗资源老路,而传统ERP管理还无法支撑数字化制造需求。文章分析了项目型制造的全流程的项目生命周期管理的特点,并通过项目型制造的关键技术的分析,提出了项目型制造的关键技术攻关路线图,重点阐述项目技术管理、项目供应链、项目生产、项目成本管理和控制中的关键技术解决方案。从而提升项目型制造业的资源整合能力,提升企业快速响应市场能力。  相似文献   
104.
在当今经济全球化、贸易自由化和社会信息化的形势下,制造业的经营战略发生了很大变化,在30-60年代企业追求的是规模效益,70年代更加重视降低生产成本,进入90年代新产品开发厦交货期成为竞争的焦点。由此产生了多种多样的制造哲理,如:精益生产、并行工程、敏捷制造和虚拟制造等,它们各有侧重,从不同角度研究如何增强企业的竞争力。而虚拟制造技术是制造技术与仿真技术相结合的产物。  相似文献   
105.
本研究目的在于探究战略网络生成中制造模式的推动作用。文章首先分析了制造模式在技术经济范式变迁中扮演的角色,总结出制造模式与技术经济范式之间的关系,接着运用数学抽象和哲学思辨的方法,提炼出人类历史上三次制造模式对技术经济范式的价值实现函数。基于该函数研究发现:精益生产中目的在于充分调动人的主观能动性,以实现人的解放的复合机制——现场管理、劳工关系管理和知识管理等体系是制造模式未来的发展方向;战略网络的演进服务于制造模式的价值实现功能,它的生成是为了弥补制造模式柔性不足的缺陷。  相似文献   
106.
In the domain of manufacturing, computer numerically controllers (CNC) technology is a major contributor to the production capacity of the enterprises. The advances in CNC technology coupled with enhancements in computing systems have provided the basis to re-examine the way in which computer-aided systems (CAx) can be used to enable global manufacturing. Interoperability of the various components of the CAx chain is therefore a major prerequisite for manufacturing enterprises for becoming strategically agile and consequently globally competitive. Being interoperable, resources can be utilized interchangeably in a plug-and-produce manner. Over the last 8 years the eminence of a STEP standard for machining entitled STEP-NC (numerical control) has become a well-known vehicle for research to improve the level of information availability at the CNC machine tool. In this paper, the authors introduce the background to the evolution of CNC manufacturing over the last 50 years and the current standards available for programming. A review of the literature in interoperable CNC manufacturing is then provided relating to milling, turn–mill and other NC processes. The major part of the paper provides a strategic view of how interoperability can be implemented across the CAx chain with a range of standards used to regulate the flow of information. Finally, the paper outlines the advantages and major issues for future developments in interoperability, identifying future key requirements and limiting factors.  相似文献   
107.
The identification of part families and machine groups that form the cells is a major step in the development of a cellular manufacturing system and, consequently, a large number of concepts, theories and algorithms have been proposed. One common assumption for most of these cell formation algorithms is that the product mix remains stable over a period of time. In today’s world, the market demand is being shaped by consumers resulting in a highly volatile market. This has given rise to a new class of products characterized by low volume and high variety. To incorporate product mix changes into an existing cellular manufacturing system many important issues have to be tackled. In this paper, a methodology to incorporate new parts and machines into an existing cellular manufacturing system has been presented. The objective is to fit the new parts and machines into an existing cellular manufacturing system thereby increasing machine utilization and reducing investment in new equipment.  相似文献   
108.
In this paper, an Adaptive Hierarchical Ant Colony Optimization (AHACO) has been proposed to resolve the traditional machine loading problem in Flexible Manufacturing Systems (FMS). Machine loading is one of the most important issues that is interlinked with the efficiency and utilization of FMS. The machine loading problem is formulated in order to minimize the system unbalance and maximize the throughput, considering the job sequencing, optional machines and technological constraints. The performance of proposed AHACO has been tested over a number of benchmark problems taken from the literature. Computational results indicate that the proposed algorithm is more effective and produces promising results as compared to the existing solution methodologies in the literature. The evaluation and comparison of system efficiency and system utilization justifies the supremacy of the algorithm. Further, results obtained from the proposed algorithm have been compared with well known random search algorithm viz. genetic algorithm, simulated annealing, artificial Immune system, simple ant colony optimization, tabu search etc. In addition, the algorithm has been tested over a randomly generated problem set of varying complexities; the results validate the robustness and scalability of the algorithm utilizing the concepts of ‘heuristic gap’ and ANOVA analysis.  相似文献   
109.
针对离散型制造业的行业特点,分析了MES的体系架构,利用J2EE的分布式多层应用开发与部署平台,构建具有多层结构的制造执行系统。提出了适合离散型制造业的功能模块。介绍了该系统的设计与应用。  相似文献   
110.
Abstract— Recently, potential breakthrough technologies for low‐cost processing of TFT‐LCDs and new process developments for flexible‐display fabrication have been widely studied. A roll‐printing process using etch‐resist material as a replacement for photolithographic patterning was investigated. The characterization of the properties of patterns formed in roll printing, a method to fabricate cliché plates for fine patterns, and the design of a new formulation for resist printing ink is reported. The pattern position accuracy, which is one of the most important issues for the successful application of printing processes in display manufacturing was studied and how it can be improved by optimizing the blanket roll structure is explained. New design rules for the layout of the thin‐film‐transistor array was derived to improve the compatibility of roll printing. As a result, a prototype 15‐in.‐XGA TFT‐LCD panel was fabricated by using printing processes to replace all the photolithographic patterning steps conventionally used.  相似文献   
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