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131.
介绍了一种基于超声波技术的乳化液浓度在线检测技术,通过检测超声波的传播速度和乳化液的温度,并利用乳化液浓度、温度和超声波声速三者之间的曲线拟合关系,来实现乳化液浓度的在线连续监测,为实现乳化液的自动配比奠定了坚实的基础。 相似文献
132.
Shin-Min Chao 《Pattern recognition》2010,43(5):1917-6849
In this paper, an anisotropic diffusion model with a generalized diffusion coefficient function is presented for defect detection in low-contrast surface images and, especially, aims at material surfaces found in liquid crystal display (LCD) manufacturing. A defect embedded in a low-contrast surface image is extremely difficult to detect, because the intensity difference between the unevenly illuminated background and the defective region is hardly observable and no clear edges are present between the defect and its surroundings.The proposed anisotropic diffusion model provides a generalized diffusion mechanism that can flexibly change the curve of the diffusion coefficient function. It adaptively carries out a smoothing process for faultless areas and performs a sharpening process for defect areas in an image. An entropy criterion is proposed as the performance measure of the diffused image and then a stochastic evolutionary computation algorithm, particle swarm optimization (PSO), is applied to automatically determine the best parameter values of the generalized diffusion coefficient function. Experimental results have shown that the proposed method can effectively and efficiently detect small defects in various low-contrast surface images. 相似文献
133.
随着计算机应用的迅猛发展,网络应用不断扩大,远程教育和虚拟大学的出现等等。传统的考试方式已经不能适应现代考试的需要。该文利用当前流行的Flex技术结合Java技术来构造RIA界面,实现在线考试系统,加强与学生的交互能力,减轻教师的工作负担及提高工作效率,与此同时也提高了考试的质量,从而使考试更趋于公证、客观。 相似文献
134.
主要介绍了博物馆智能投币系统设计的具体方案。其适用于无人操作以投币方式触发控制周边设备。主要通过涡流传感器对投入硬币币值的检测及真假币判断,并由此产生相关控制信号来模拟开关动作或控制周边强电设备,使游客能够自主参与各种互动环节。 相似文献
135.
136.
基于无线通信的设备点检系统 总被引:1,自引:0,他引:1
针对传统设备点检系统工作效率低、劳动强度大、准确性低、实时性差等问题,提出了一种基于无线通信的设备点检系统。该系统结合了单片机、无线通信和计算机信息管理等技术,具有多元化通信方式,包括无线射频(RF)通信、GSM通信和Internet通信,能够在线检测现场设备的振动、温度、压力等主要参数,并能根据环境情况进行预警,同时具有远程监测功能。测试结果表明,该系统稳定性强,显著提高了设备点检系统的操作管理品质。 相似文献
137.
138.
The defect of process equipments is a major factor that impairs the yields in the mass production of semiconductor wafer fabrication and it is a main supervision means to use high-resolution defect inspection tools to detect and monitor the defect damage. Due to the high investment costs of these inspection tools and the resulting decrease in the throughput, how to improve the sampling rate is an important issue for the associated inspection strategy. This paper proposes a new concept and implementation of virtual inspection (VI) to enhance the detection and monitoring of defect in semiconductor production process. The underlying theory of the VI concept is that the state variables identifications (SVIDs) of process equipments can reflect the process quality effectively and loyally. The approach of VI is to combine the application of the fault detection and classification (FDC), and the defect library and the re-engineering of inspection procedure to reach the full-scope of strategic objective. VI enables the defect monitoring to enter a new era by promoting the monitoring level of defect inspection from the previous lot-sampling basis to the wafer-sampling level, and hence upgrades the sampling strategy from random-sampling to full and right-sampling. In this study, various typical defect cases are utilized to illustrate how to create VI models and verify the reliability of the proposed approach. Furthermore, a feasible architecture of the VI implementation for mass production in semiconductor factory is presented in the paper. 相似文献
139.
Ö. Özgür Tanr?överAuthor Vitae Semih BilgenAuthor Vitae 《Computer Standards & Interfaces》2011,33(5):448-464
Conceptual models are used in understanding and communicating the domain of interest during analysis phase of system development. As they are used in early phases, errors and omissions may propagate to later phases and may be very costly to correct. This paper proposes a framework for evaluating conceptual models when represented in a domain specific language based on UML constructs. The framework describes the main aspects to be considered when conceptual models are represented in a domain specific language, presents a classification of semantic issues and some evaluation indicators. The indicators can, in principle, identify situations in the models where inconsistencies or incompleteness might occur. Whether these are real concerns might depend on domain semantics, hence these are semantic, not syntactic checks. The use of the proposed review framework is illustrated in the context of two conceptual models in a domain specific notation, KAMA. With reviews based on the framework, it is possible to spot semantic issues which are not noticed by case tools and help the analyst to identify more information about the domain. 相似文献
140.
滑油中金属屑监控和在线处置已成为保障国内外新一代发动机健康运转的主要技术手段.通过脉冲电流技术,研制一种储能装置和烧蚀装置,实现直升机发动机滑油中正常磨损金属屑在线处置能力.通过直升机飞行中控制程序,减少金属屑虚警率,确保发动机健康高效地运转.填补了国内直升机发动机滑油中金属屑在线处置技术的空白. 相似文献