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101.
Model predictive control (MPC)-based approach to fab-wide scheduling has been suggested to solve constraint-aware production optimization and in-process inventory level control simultaneously at each scheduling instance. However, application of this approach to real fab suffers from computational difficulties brought by the need to solve a huge optimization problem on-line as real fab scheduling problems are characterized by long cycle times, multiple product types, hundreds of machines/processing steps and re-entrant product flows. This study explores the use of an offset-blocking strategy combined with a modified recursive least square (RLS) estimation in the fab-wide scheduler, in order to alleviate the difficulty. The strategy is tested on a modified version of published case study called Intel Mini-Fab (IMF) problem. Despite its simplicity, the blocking strategy showed excellent performance in the face of realistic demand changes and plant/model mismatch.  相似文献   
102.
We present a high speed optical profiler (HSOP) using frequency-scanning lasers for three-dimensional profile measurements of microscopic structures. To improve upon previous techniques for implementing the HSOP, we developed frequency-scanning lasers and a compact microscopic interferometer. The controller of the HSOP was also modified to generate proper phase-shifting steps. For measurements of step height specimens, the HSOP showed results comparable with a commercial optical profiler, even with much higher measurement speeds (up to 30 Hz). The typical repeatability of step height measurement was less than 1 nm. We also present measurements of microscopic structures to verify the HSOP's ability to perform high speed inline inspection for the semiconductor and flat-panel display industries.  相似文献   
103.
104.
The potential benefits of thumb-based touch interaction have not been fully exploited due to its usability problems and performance deterioration. Despite the well-known problems, mobile phone users often prefer thumb-based input method in their daily context of use. Without understanding input performance under realistic variability, design solutions may not address the problems adequately. This research aims to evaluate performance of one-handed thumb-based input compared to cradled finger-based input for the large number of users and varying task conditions. By investigating performance under a range of user- and task-variability, common patterns can be identified to help infer realistic performance in context of use. For this experiment, 259 participants were recruited balanced on gender and age. They performed user testing of moving an icon on a mobile touch-screen. Overall, the one-handed thumb input showed a 30% reduction in throughput compared to the cradled finger-based input, with significant reduction in speed and accuracy. Reduced throughput is attributed to inaccuracy rather than speed. In addition, the partial effects of touch position, dragging direction, and target size were investigated and quantified. In conclusion, performance could maintain constant throughput only for the finger-based input of limited task conditions, when realistic variability was introduced. Also, high variance of throughput for the thumb-based input led to poor conformity to Fitts’s law. The findings have implications for design of thumb-based touch interface to offset performance reduction and characterizing performance measure for thumb-based input method.  相似文献   
105.
The Toyota production system (TPS), or lean production, has been associated with many benefits for manufacturing firms that implement the system. However, to implement the TPS successfully, it is necessary to integrate the so‐called “hard side” of the system (that is, the technical aspects of material handling) with the “soft side” of the program (that is, the aspects associated with human factors). The present study makes a contribution to such a holistic view of the TPS by proposing an integrated model that consists of the technical aspects of the TPS, together with elements associated with total quality management (TQM), human resources management (HRM), and certain identified “people factors.” The study then uses structural equation modeling (SEM) to test this holistic model using data obtained from a questionnaire survey of 153 Taiwanese manufacturing firms. The empirical study confirms the appropriateness of the causal model, which is evaluated by several goodness‐of‐fit methods. The study confirms the proposition that the inclusion of the “people factors” together with TQM and HRM significantly improves the realization of benefits associated with the TPS practices of “just‐in‐time” (JIT) and “autonomation.” The conclusion is that such an integrated model provides a much more effective “lean system” and has the potential to produce significantly enhanced benefits for firms that implement it. © 2012 Wiley Periodicals, Inc.  相似文献   
106.
This work presents a driving system for a peristaltic micropump that is based on piezoelectric actuation. The effects of the actuation sequence on pump performance are also considered. A valveless peristaltic micropump based on piezoelectric actuation is designed and fabricated using microelectromechanical system technology. The pump has three parts––silicon, Pyrex glass and commercially available bulk PZT (lead zirconate titanate) chips. The peristaltic micropump actuated by PZT chips comprises three chambers that are in series. The driving system consists of an ATmega 8535 microprocessor, a high voltage power supply, three differential amplifiers, a phase controller, an A/D converter, a 555 oscillator and an LCD module. It is supplied via a 110 Vrms 60-Hz AC line and is programmable. The system can produce step-function signals with voltages of up to 100 Vpp and frequencies ranging from 10 Hz to 1 kHz, as the inputs for the pump. Fluid pumping with air is successfully demonstrated. Additionally, 3-, 4- and 6-phase actuation sequences for the pump are designed and used to study the effects on pump performance, as revealed by the flow rate and the displacement of a pump diaphragm. The experimental results show that the flow rate and the displacement of the diaphragm actuated by the 4-phase sequence exceed those actuated by the 3- and 6-phase sequences. A flow rate of 17.6 μl min−1 and a displacement of 2.91 μm (peak-to-peak) in 4-phase peristaltic motion are achieved at 100 Hz and 100 Vpp. The results demonstrate that the pump actuated in the 4-phase sequence is the most efficient. Consequently, the actuation sequences can affect the pump performance.  相似文献   
107.
首先简要介绍语义Web服务资源描述框架(RDF4S),在此基础上提出语义Web服务包装机制,语义Web服务经包装后,分别通过组合接口和调用接口为组合语义Web服务的设计与调用提供支持.然后分别详细介绍组合语义Web服务的设计存储和调用执行:通过图形化的设计工具按照语义Web服务的3种基本逻辑关系设计组合结构图,然后将该图映射到组合结构信息表存储,组合语义Web服务执行时根据结构信息表生成语义Web服务代理对象和相应的语义消息,再根据语义消息传递机制调用Web服务实体.最后用一个实例展示组合语义Web服务执行时的消息传递,试验表明该方法有效.  相似文献   
108.
This paper describes a concerted effort to design and implement a robotic service framework. The proposed framework is comprised of three conceptual spaces: physical, semantic, and virtual spaces, collectively referred to as a ubiquitous robotic space. We implemented a prototype robotic security application in an office environment, which confirmed that the proposed framework is an efficient tool for developing a robotic service employing IT infrastructure, particularly for integrating heterogeneous technologies and robotic platforms.  相似文献   
109.
针对人类用自然语言与机器交互所面临的巨大鸿沟,提出了一种基于类自然语言的语义对象行为语言。SOBL是一种宣称式的陈述语言,用于开发数据库驱动的应用,支持复杂的用户交互,主要由一个Semantic Objects^TM的对象关系开发框架所支持。该语言扩展结构化自然语言,携带语义信息,能够面向非程序员使用,降低了软件的开发难度。最后通过一个具体的实例验证了该语言的有效性。  相似文献   
110.
Dissolving microneedle (DMN) is an attractive alternative to parenteral and enteral drug administration owing to its painless self-administration and safety due to non-generation of medical waste. For reproducible and efficient DMN administration, various DMN application methods, such as weights, springs, and electromagnetic devices, have been studied. However, these applicators have complex structures that are complicated to use and high production costs. In this study, a latch applicator that consists of only simple plastic parts and operates via thumb force without any external complex device is developed. Protrusion-shaped latches and impact distances are designed to accumulate thumb force energy through elastic deformation and to control impact velocity. The optimized latch applicator with a pressing force of 25 N and an impact velocity of 5.9 m s−1 fully inserts the drug-loaded tip of the two-layered DMN into the skin. In an ovalbumin immunization test, DMN with the latch applicator shows a significantly higher IgG antibody production rate than that of intramuscular injection. The latch applicator, which provides effective DMN insertion and a competitive price compared with conventional syringes, has great potential to improve delivery of drugs, including vaccines.  相似文献   
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