On managing the human factors engineering of hybrid productionsystems

In the transition toward total automation, contemporary manufacturing systems are predominantly composed of production equipment that is neither completely manual or automated. The development of these systems, identified as hybrid production systems, employ and integrate the capacities of human operators with intelligent machines. It is argued that human activities in hybrid automated systems are critical in achieving productivity gains. Given this importance, hybrid systems must be designed to optimize production. Optimal human factors engineering is possible only when engineers and their management are aware of the technical challenges, created by hybrid systems, and the range of options available for meeting these challenges. The authors describe these challenges and their possible solutions, specifically targeted to the management of engineering and technology-based organizations     

Developing a data-collection system for PCB assembly: a case studyin software engineering

For manufacturing firms to increase productivity and quality while reducing their inventory and operational costs, a simple and easy-to-use data collection system is needed on the shop floor. Such a system developed for an electronic card manufacturing line is discussed. Facility operations are described, and the requirements for an ideal software solution are outlined. An independent development effort was undertaken to satisfy the unique requirements of the production line. As work progressed, a number of factors conspired to produce schedule and cost overruns that caused management to scale back the scope considerably. What eventually emerged was a much leaner and less capable system than originally envisioned. The factors that put the project in jeopardy are discussed, and some suggestions and lessons gained from the experience, which are applicable to any software development project, are offered     

Adoption of just-in-time manufacturing methods at US- andJapanese-owned plants: some empirical evidence

Since the early 1980s, when Japanese manufacturing firms in a number of industries-including auto, electronics, and machinery-achieved high levels of international competitiveness, Japanese manufacturing practices-particularly those associated with just-in-time manufacturing (JIT)-have attracted considerable attention in North America. Transfer to the United States of JIT is characterized by special production management practices involving inventory and quality control, industrial relations, and supplier-manufacturer relationships. Because so many different aspects of plant operation are involved, the transfer of JIT requires a substantial effort on the part of US manufacturers. Despite this barrier, anecdotal evidence suggests that substantial transfer of Japanese production methods has taken place and that this transfer has had a significant impact on the performance of US manufacturing plants. However, there is little empirical evidence of this process that is based on broad samples of plants and workers from various manufacturing industries. The purpose of this paper is to help fill this gap in the literature. Using a sample of US and Japanese-owned manufacturing plants in the United States in three different industries, we show that the implementation of JIT has improved many of the performance measures for these US manufacturing plants     

Gigabit age microelectronics and their manufacture

The benefits of gigabit chips, which will enter production around the year 2000, are discussed. These chips will be enablers for smart and brilliant systems. The systems will be ultralow power. The design and software productivity enhancements needed are described. The numerous manufacturing challenges that lie ahead in the 1990s represent opportunities to implement advanced concepts currently under development in the industry. It is predicted that software-driven concepts such as flexible manufacturing and distributed computer integrated manufacturing will evolve. Processing concepts using cluster tools, real-time process control, all-dry processing, and wafer microenvironments should be ready for manufacturing in the gigabit age. The costs of electronics should continue to decrease, concomitant with extraordinary increases in functionality and performance     

A new manufacturing control system using Mahalanobis distance for maximizing productivity

Primary productivity in the semiconductor manufacturing industry, which includes cycle time, cost, and production, depends to a great extent on the capability of manufacturing administrators (MA), particularly with regards to the critical tradeoff between cycle time and tool utilization. The Mahalanobis distance (MD) has significance in pattern recognition, and the authors have found a method to make use of the MD as the core of a manufacturing control system. By using this system, one can easily distinguish deviations from normality in respect to productivity, specify the root cause of the abnormality, and decide how to prioritize the problem. As a result, one can efficiently concentrate limited resources on the root cause in the absence of a capable MA and restore productivity on a minimum timescale.     

Experience on Pre-Series and Series Production of LHC Dipoles Cold Masses in ASG Superconductors

In 1986 Ansaldo Magnet Dept. (now ASG Superconductors) started, in cooperation with CERN, the design activities of the first 1 m-8 T LHC prototype dipoles. After several design steps and the manufacturing of 1+3 prototype dipoles 10 m long, the final design configuration 15 m long was defined by CERN. During the following years, a very close collaboration with CERN engineers and technicians lead to define the parameters about the most critical manufacturing processes, in particular winding of s.c. cable, collaring of coils, cold mass welding and test procedures. In the meantime, installation and commissioning of all the manufacturing plants followed: winding machines, curing presses, collaring press and welding press were installed, as well as geometrical measurements stations and vacuum chamber for leak test. Finally two manufacturing halls were fully dedicated to LHC dipoles production. At the beginning of year 2002, all the manufacturing plants were coming to be operational, ready to start the large scale production of LHC cold masses: 30 pre-series, 386 series and 30 spare cold masses have been produced till May 2007, to get a total number of 446 cold masses. In this paper we summarize all the data collected during a five years production: main manufacturing data, test results and production rate are presented. Final results about tests performed at CERN in superfluid He at 1.9 K are also included as well as correlation between test result and manufacturing rate.     

Quality-oriented-maintenance for multiple interactive tooling components in discrete manufacturing processes

In discrete manufacturing processes such as stamping, assembly, or machining processes, product quality, often defined in terms of the dimensional integrity of work pieces, is jointly affected by multiple process variables. During the production phase, the states of tooling components, which are measured by adjustable process variables, are subject to possible random continuous drifts in their means & variances. These drifts of component states may significantly deteriorate product quality during production. Therefore, maintenance of the tooling components with consideration of both their continuous state drifts as well as catastrophic failures is crucial in assuring desired product quality & productivity. In contrast to traditional maintenance models where product quality has not been well addressed, especially for discrete manufacturing processes, a general quality-oriented-maintenance methodology is proposed in this paper to minimize the overall production costs. In this research, the total production cost includes product quality loss due to process drifts, productivity loss due to catastrophic failures, and maintenance costs. The quality-oriented-maintenance model is built based on a response model linking process variables with multidimensional product quality. It can be obtained either from engineering analysis for specific processes, or from statistical design of experiments. Three typical multi-component maintenance models are investigated under the general quality-oriented-maintenance framework. A case study for a sheet-metal stamping process is presented to demonstrate the effectiveness of the proposed methodology.     

Comparison of manufacturing performance of three team structures insemiconductor plants

Manufacturing programs aimed at improving performance often feature employee teams that address production problems at the shop-floor level. According to cognitive models of participation, performance under such programs is improved via the better utilization of skills and knowledge that occurs as employees are allowed greater decision making in their tasks. The authors examine the cognitive-model premise in a high-technology industry where improvement-team programs are on the rise. The study three types of improvement-team programs among a sample of eight manufacturing sites. The programs feature continuous improvement teams (CITs), quality circles (QCs) or self-directed work teams (SDWTs) and vary in the amount of decision-making power, skill attainment via training and skill use granted to employees. A quantitative analysis of performance reveals that CIT programs were associated with the highest direct and indirect productivity, two metrics that were available for each firm. QC and SDWT programs should not be dismissed, however, as they may lead to improvements in quality metrics, as the authors note in suggestions for future research. Qualitative data gathered in site visits suggest that poor implementation and failure to integrate production programs with engineering departments are two factors that inhibit program success     

Manufacturing cost of active-matrix liquid-crystal displays as afunction of plant capacity

This work models the cost of 10-in class active-matrix liquid-crystal display (AM-LCD) manufacturing as a function of plant capacity for both first generation plants in 1993 and second generation plants in 1995. In order to model manufacturing costs as a function of plant capacity, this work distinguishes between capacity-dependent and capacity-independent costs. Among the costs included in our model are the costs of capital equipment, materials and labor. Decreases in materials and components costs and improvements in process yield are shown to be the primary factors driving reductions in manufacturing cost per display for large-scale plants. The minimum efficient scale is found to be roughly 57000 displays per month for a first generation plant and roughly 150000 displays per month for a second generation plant     

Tactical flexibility of manufacturing technologies

In discrete manufacturing the smooth running of a factory is a goal that is often not attained. Smooth running depends on the ways that everyday problems are tackled on the factory floor. The efforts of factory personnel in this regard are challenged when new technologies are introduced, as is the case with the computer-based manufacturing technologies (CBMT) in the automotive industry. The tactical flexibility of a workstation, its ability to deal with the deviations from norm, is argued to be reduced as the CBMT replaces other technologies. This change is accompanied by changes in many factory floor activities. With this perspective, the authors identify not only the problems affecting workstations in modern plants but also the plant-specific solutions to these problems. Data collected from four Canadian automotive plants through a questionnaire are shown to generally support this framework and are used to draw conclusions relevant for production managers and technological strategists     

计算机生产中的条形码管理系统

产品质量记录及部品追溯是生产中较为重要但又较困难的环节，现提出条形码管理方案来系统地解决这些问题，以图达到控制产品质量，提高生产效率的目的。     

彩管厂排气炉内管子炸裂原因初探

排气炉内管子炸裂一直是各彩管厂头痛的问题，由于引起炸裂的原因复杂，涉及的因素众多。给解决炸裂问题带来许多困难。另外，管子到排气工序已是制作后期，炸裂给彩管厂带来很大损失。如何减少炸裂，降低成本，增加效益成为彩管厂关注的焦点。本文尝试从玻壳尺寸入手分析管子炸裂原因。提出改进措施。     

The impact of flexible manufacturing systems on productivity andquality

Worldwide competition and the pace of technological innovation will not permit distraction from industry's primary task: producing quality products at competitive prices. A flexible manufacturing system (FMS) provides a good means of improving this situation. Nevertheless, an FMS implementation usually costs an organization millions of dollars, and the long payback period for an FMS may hinder management from adopting this technology. It is therefore necessary that both financial and strategic benefits produced from the acquisition of an FMS be evaluated on a long-term basis. Flexible manufacturing systems are widely claimed to positively impact productivity and quality. From an extensive search and analysis of empirical studies, propositions regarding issues of flexibility, productivity, and quality are presented. Major findings show FMS investment leading to reduced labor costs, increased output, decreased manufacturing costs, increased flexibility, and reduced production lead time     

In Situ and Real-Time Monitoring of Plasma Process Chamber Component Qualities and Predictive Controlling of Wafer Yields

Plasma interactions with chamber components and wafers in semiconductor manufacturing processes have been monitored with a fault detection technique. Not only can this diagnostic technique monitor the wafer and process chamber components qualities, but it also has potential in saving tremendous amounts of manufacturing costs and improving equipment productivity. We have discovered that the abnormality in certain plasma processing parameters detected in the early stages of a manufacturing line can have a strong correlation with the product yield. Possible reasons for the observed correlations are explained     

Efficient scheduling policies to reduce mean and variance ofcycle-time in semiconductor manufacturing plants

The problem of reducing the mean and variance of cycle time in semiconductor manufacturing plants is addressed. Such plants feature a characteristic reentrant process flow, where lots repeatedly return at different stages of their production to the same service stations for further processing, consequently creating much competition for machines. We introduce a new class of scheduling policies, called Fluctuation Smoothing policies. Unanimously, our policies achieved the best mean cycle time and Standard Deviation of Cycle Time, in all the configurations of plant models and release policies tested. As an example, under the recommended Workload Regulation Release policy, for a heavily loaded Research and Development Fabrication Line model, our Fluctuation Smoothing policies achieved a reduction of 22.4% in the Mean Queueing Time, and a reduction of 52.0% in the Standard Deviation of Cycle Time, over the baseline FIFO policy. These conclusions are based on extensive simulations conducted on two models of semiconductor manufacturing plants. The first is a model of a Research and Development Fabrication Line. The second is an aggregate model intended to approximate a full scale production line. Statistical tests are used to corroborate our conclusions     

Linking Internal Process Technology Development and the Use of AMT With Manufacturing Plant Performance---An Examination of Complementarities and Redundancies

In this paper, we distinguish between the internal and external means by which manufacturing plants engage in process technology development. While computerized and equipment-based advanced manufacturing technologies (AMT) are typically sourced from external vendors, plants also develop proprietary process technologies in-house. We present internal process technology development (IPTD) as a construct that captures this internal means of process technology development, and investigate the individual and interaction effects of IPTD and externally sourced computerized and equipment-based AMT on manufacturing plant performance. Our results indicate that IPTD is positively associated with quality, delivery, and process flexibility, but it is not significantly associated with cost efficiency or new product flexibility. The indicated relationships between the use of specific types of AMT (process, design, and planning AMT) and manufacturing plant performance and between IPTD-AMT interactions and manufacturing plant performance suggest context specificity. In addition, the findings suggest the existence of complementarities as well as the redundancies among IPTD-AMT relationships.     

A distributed scheduling for agro-food manufacturing problems

Workshop scheduling problems can be considered as one of the main factors to improve the productivity and efficiency of a manufacturing system. The continuous evolution and the dynamic characteristics of industrial workshops, particularly those of agro-food industries, impose the generation of a real time decision scheduling process. In the agro-food industries, the products to be processed and the used primary products are characterized by their limit validity dates which generate some particularly and especially antagonist criteria. A distributed decision support system for real time scheduling is described in this paper. It is based on an original cooperative approach aimed to elaborate robust decisions that propose to the "best action" to the decision maker. The decision process is distributed all along the production chain. At each decision time, in order to ensure coherency, we have to take into account the neighborhood constraints in order to simultaneously satisfy different criteria which do not have the same importance. An aggregation criteria system is defined to manage the criteria among their importance degrees. We define a decisional model based on the evaluation and the comparison of a set of proposed actions.     

Quick-turnaround-time improvement for product development andtransfer to mass production

We describe equipment and facility operational methods in a production fab which are designed to achieve quick-turnaround-time (QTAT) manufacturing and ease product transfer from development to mass production. An advanced CIM system with precise lot management is introduced to keep the optimum balance of manufacturing TAT and throughput. Substantial end-user computing reduces the engineering holding time for handling development lots. In situ monitoring technologies are applied for the utilization enhancement of plasma-assisted equipment. A 9% manufacturing TAT reduction and a 14% throughput increase are estimated using a manufacturing simulator. The number of wafers in QTAT lots is reduced for processing time reduction. As a result, manufacturing TAT of QTAT lots with reduction from 24 wafers to three is reduced to 56% compared with that of normal lots in the production fab. This new production fab realizes QTAT development and agile product transfer from development to mass production with full process compatibility     

New machines for old [manufacturing computer control]

ICL is currently implementing a phased CIM strategy at its printed circuit board (PCB) manufacturing site at Kidsgrove. The manufacturing process begins with laminate and components entering the factory, and ends with tested PCBs leaving to be fitted into products at ICL's assembly plants or stored for field spares. The author shows that one of the major problems in installing computer-integrated and flexible manufacturing systems (for PCB production applications) is the integration of existing numerically controlled machines