共查询到20条相似文献,搜索用时 15 毫秒
1.
为了降低热压印工艺制作微透镜阵列对模具的要求,提出了非接触式热压印工艺制作微透镜阵列,采用了自主研制的纳米压印样机与光刻工艺制作的通孔式不锈钢模具在PMMA表面压印出微透镜阵列,并分析了压印过程中温度、压力、时间等参数对微透镜阵列表面形貌的影响。研究结果表明,利用非接触式热压印工艺可以制作表面形貌好、位置精度高的微透镜阵列,压印时最佳压印温度为140℃~180℃,最佳脱模温度为80℃,最佳压力为1 500 Pa~3 500 Pa,且采用通孔式模具不需要真空,降低了对环境的要求。 相似文献
2.
A basic principle for acquiring precisely shaped machined parts is to create dense tool path data. However, as the density of tool paths increases, the volume of data increases. The significant increase in data consumes more memory and machining time. Therefore, the creation of tool path data of unlimited density is impractical. This paper proposes a contour error evaluation system. The system makes correct decisions based on the expected quality of a workpiece. Specifically, the user creates tool path data by calculating deviations in the contour in relation to variations in the intervals of the tool path. The user can create tool paths by adjusting the amount of tool path data within the desired quality level. Accordingly, before the start of the machining process, the user can predict any machining loss likely to result from the excessive amount of data created in the creation phase. In addition, the tool path data of the proposed system are experimentally compared with the actual shape of a part machined with a microlens array machining system. 相似文献
3.
4.
By inserting a microlens array at the intermediate image plane of an optical microscope, one can record four-dimensional light fields of biological specimens in a single snapshot. Unlike a conventional photograph, light fields permit manipulation of viewpoint and focus after the snapshot has been taken, subject to the resolution of the camera and the diffraction limit of the optical system. By inserting a second microlens array and video projector into the microscope's illumination path, one can control the incident light field falling on the specimen in a similar way. In this paper, we describe a prototype system we have built that implements these ideas, and we demonstrate two applications for it: simulating exotic microscope illumination modalities and correcting for optical aberrations digitally. 相似文献
5.
6.
Suhua Hsieh Kai-Chung Hou 《The International Journal of Advanced Manufacturing Technology》2006,30(7-8):727-737
In a wafer manufacturing system, the value added to a particular product at a station may differ significantly from that added to a different product at the same station. If an enterprise concentrates mainly on generating profits, throughput becomes a poor performance measurement for a manufacturing system. Job dispatching rules based on maximum throughput no longer guarantee maximizing profit. Hence, profitability would be a good alternative measurement. The main purpose of this study is to develop a production-flow-value-based job dispatching rule (PFV) by the theory of constraints (TOC) for wafer fabrication. This study derives a TOC cost estimation method and a profitability estimate of a WIP-wafer lot. Jobs are then prioritized based on their profitability. Thus the PFV job dispatching rule is developed. For comparison, two job dispatching rules, MCR and MBS, are also arbitrarily selected to perform simulations. The simulation results reveal that the proposed PFV maximizes the production flow value, while MCR and MBS do not. 相似文献
7.
介绍了工程机械中液力离合器加工工艺的新方法,并通过计算和大量试验确定了该方法在生产中的可行性与经济 性。 相似文献
8.
制造网格中资源的层次检索方法研究 总被引:2,自引:1,他引:2
分析了传统资源搜索方法应用在制造网格中的局限性,建立了制造网格中资源的信息模型和层次检索模型。在此基础上,提出了一种制造网格中资源的优化检索方法,通过与其他算法比较并结合实例验证了该检索方法的高效性与可行性。 相似文献
9.
Jingzhi Fu 《The International Journal of Advanced Manufacturing Technology》2014,74(1-4):335-340
Manufacturing grid has become more and more popular because it can realize the resource share and collaboration within the worldwide scope. In most cases, the resource and task information in manufacturing grid is fuzzy and uncertain, but the resource-searching methods now are focused on deterministic value and have some limitations for manufacturing grid. This paper proposes a unified information model in which the information parameters are described as a set of interval values, and the conversion rules from the given capability parameters into intervals are discussed. On these bases, a new optimized resource-searching method is designed to find the best required manufacturing resource for the task by calculating the interval distance of the task and the resources. The method is verified to be effective by an instance. Furthermore, it is practical by comparing it with other resource-searching methods. 相似文献
10.
This paper reports a novel method for highly controllable local patterning of a hydrogel on microcantilevers. We constructed a dynamic mask lithography setup based on a commercial beam projector and a 3-axis microstage. Dynamic masks generated from the beam projector controlled the shape, size, and position of hydrogel patterns while the 3-axis microstage mainly controlled the thickness of hydrogel patterns. Using the constructed setup, polyethyleneglycol diacrylate (PEGDA) was patterned on microfabricated cantilevers in a highly controlled manner. Currently, the smallest PEGDA patternable is a 5-μm-diameter circle with a thickness of ~10 μm. To confirm thicknesses of patterned PEGDAs, resonance frequencies of microcantilevers were measured before and after each PEGDA patterning. Thicknesses extracted from resonance measurements showed good agreement with measurements using an optical microscope. 相似文献
11.
12.
螺旋叶片是机械工程上经常遇到的一种较难放样的钣金构件,其制作方法繁琐,成本较高。通过采用拉伸制作方法和卷制方法,简便易行,成本较低,卷制方法可实现连续大批量生产。 相似文献
13.
为了使制造执行系统功能在其生命周期中能够不断满足企业业务需求的变化,提出一种基于企业业务活动模型与制造执行系统功能模型转换的功能进化实施方法.建立了进化过程模型,并对进化过程进行描述,给出了企业业务活动元模型与制造执行系统功能元模型,以及两者之间的转换框架.通过转换,将企业业务的变化映射到制造执行系统功能模型中,在功能模型驱动下完成系统进化.通过在某航空企业的实施验证了该方法的可行性. 相似文献
14.
面向工艺领域的制造知识系统化建模方法研究 总被引:4,自引:1,他引:3
针对复杂产品工艺领域制造知识的组成和结构,基于知识的信息本质,采用系统的方法对制造知识进行了分析,提出了制造知识的系统化建模方法;从宏观整体性角度,建立了把领域知识自上而下划分为最小粒度知识的分类方法,用知识型谱刻画知识层次结构;从微观相关性角度,建立了制造知识的信息构成关系和拓扑构造方法,用记忆网络刻画制造知识拓扑结构,根据工艺领域制造知识的拓扑结构就可构建知识库.通过在飞机钣金工艺领域制造知识建模中的应用说明了该方法的有效性. 相似文献
15.
16.
17.
18.
针对网络化制造中制造过程访问冲突问题,分析了现有冲突消解方法在解决多任务域访问冲突中存在的不足,并深人研究了制造过程访问冲突产生的原因,提出了一种基于制造任务及工期的并发冲突消解方法.该方法将制造过程访问冲突消解转化为多任务域工作流下制造任务访问优先模型的求解,建立了多任务域工作流下制造任务访问优先模型.根据求解得到的优先向量,按照冲突消解步骤实现冲突消解.最后基于上述原理,开发了访问控制原型系统,并将企业应用实例与现有方法进行对比,结果表明,该方法可行且有效. 相似文献
19.
针对可重入制造系统处于高度不确定性环境中,其产出时间序列的非线性特征,提出了基于遗传小波神经网络的产出短期预测方法,使预测模型具有小波的优良逼近性质和神经网络的自学习自适应性质,同时,采用遗传算法训练神经网络参数,利用遗传算法隐含并行性和全局搜索性的特征,丰富优化过程中的搜索行为,增强全局和局部意义下的搜索能力和效率。通过半导体生产线实例,进行了验证,结果表明所提出的基于遗传小波神经网络的产出短期预测方法的预测性能要优于传统BP神经网络算法。 相似文献
20.
在分析现有制造执行系统面临的挑战和机遇的基础上,结合最新的物联网技术,提出一种“物物互联,感知制造”环境下的制造执行系统…基于物联技术的制造执行系统。设计了一种基于物联技术的制造执行系统体系构架,提出了一套使能基于物联技术的制造执行系统关键技术体系和实现框架,包括基于传感网的制造资源物物互感技术、制造执行过程多源信息的主动感知与增值技术、制造执行过程动态优化技术、生产过程质量信息传感/监控和全程追溯技术等,所提方法和技术对于物联网在制造领域的应用具有重要的借鉴价值。 相似文献