• 산업경영시스템학회지
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• 제37권1호
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• pp.127-132
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• 2014

This study is concerned with process capability index in single process. We enumerated issues on the calculation of process capability index and described the effects of these issues. We explained the development process and the reason of the representative existing process capability indices. We investigated whether the indices agree with the concept of process capability and drew the problems from those results. In addition, we proposed alternative and direction to seize the process capability necessary to the field.

• 품질경영학회지
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• 제20권1호
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• pp.147-157
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• 1992

This article describes a prototype expert system for yarn spinning process planning in textile industry. This expert system is intended as a consultant to give the technicians interactive assistance for the appropriate process planning in accordance with used materials, required count, and other factors affected yarn spinning by means of many types of machine. Also, this system has the other function that can be compared the standard values with the measured ones for quality characteristics control. VP-EXPERT-a rule-based microcomputer expert system development tool-provides the expert system components for this development. The details of knowledge organization, rule representation, inference reasoning process, and performance of this expert system are demonstrated with the practical yarn spinning operations.

• 한국기계가공학회지
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• 제12권5호
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• pp.163-169
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• 2013

The objective of this study is to replace labor intensive forging processes by an automated system. For achieving it, an exclusive mechanism that consists of a positioner, an arm, and a hanger is configured to handle hot forging objects. Also, a structural analysis is applied to the horizontal motion unit, which is the most highly loaded, in order to verify its validity. In addition, its possibility is also verified through identifying the performance of the proposed system before applying it to sites. As a result, the major characteristic items, such as positioning accuracy, material diameter, object traveling weight, product failure rate, and forging process rate, in this system are perfectly verified for applying it to manufacturing sites.

• 한국CDE학회논문집
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• 제5권1호
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• pp.61-70
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• 2000

The design and development of a Web-based Workflow Management System (WfMS) is described in this paper. WfMSs are employed by many organizations to manage their business processes efficiently. The goal of this research is to provide an effective management of design processes in a distributed and heterogeneous environment-an environment in which workflow participants are geographically dispersed and use different computing platforms. We identify the requirements of WfMSs for the distributed and heterogeneous environment. We present an approach to applying the Web technology to was. The developed system is composed of three main modules: Worflow Engine, Web-based clients, and Process Designer. The workflow engine is implemented in pure Java for portability to heterogeneous platforms. furthermore, the client interfaces are all programmed using applets, and thus they can be readily accessed through the Internet/intranet. The Process Designer provides a build-time function of generating process specifications. Some important functions of the developed system are explained in this paper. A prototype system has been developed and applied to design processes. The system allows effective cooperation among designers who may be geographically separated.

• 제어로봇시스템학회논문지
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• 제7권6호
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• pp.494-501
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• 2001

In this paper an ANFIS(Adativo Neuro-Fuzzy Inference System)- based fault detection and diagnosis for a closed loop control system is proposed. The proposed diagnostic system contains two ANFIS. One is run as a parallel model within the model in closed loop control(MCL) and the other is run as a series-parallel model within the process in closed loop(PCL) for the generation of relevant symptoms for fault diagnosis. These symptoms are further processed by another classification logic with simple rules and neural network for process and controller fault diagnosis. Experimental results for a DC shunt motor control system illustrate the effectiveness of the proposed diagnostic scheme.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.71-72
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• 2007

• 산업공학
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• 제20권3호
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• pp.288-297
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• 2007

Success of semiconductor/LCD industry depends on its yield and quality of product. For the purpose, FDC (Fault Detection and Classification) system is used to diagnose fault state in main manufacturing processes by monitoring time series data collected by equipment sensors which represent various conditions of the equipment. The data set is segmented at the start and end of each product lot processing by a trigger event module. However, in practice, segmented sensor data usually have the features of data asynchronization such as different start points, end points, and data lengths. Due to the asynchronization problem, false alarm (type I error) and missed alarm (type II error) occur frequently. In this paper, we propose a robust process fault detection system by integrating a process event detection method and a similarity measuring method based on dynamic time warping algorithm. An experiment shows that the proposed system is able to recognize abnormal condition correctly under the asynchronous data situation.

• 시스템엔지니어링학술지
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• 제5권2호
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• pp.27-34
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• 2009

This paper analyze technical review entry criteria and review process based on system property, and review checklist to conform technical review is also showed. The execution of review is determined according to the preparation of review item and identification for risk element. Risk level should be mitigated before technical review by appropriate plan. This paper described the entering condition of technical review for developmental phase, and tailoring consideration for technical review condition. Described technical review entry criteria, review process, and tailoring consideration is applied to development of test equipment for ground ant-air missile system. Applied system specific technical review process, tailored entry condition for test equipment for ground ant-air missile system and review check list is showed and the effectiveness of described system specific technical review process is presented.

• 산업경영시스템학회지
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• 제44권2호
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• pp.93-101
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• 2021

The purpose of this study is to analyze the adequacy of production capacity of the assembly process system of mobile bath vehicle's top box panel and process design through a simulation analysis. Towards this end, the layout of the facility designed with pre-verification job using a simulation modeling and an experiment, and facility, logistics process, and personnel input method were made into a simulation model, and the design system's adequacy was evaluated through an experiment. To produce 120 mobile bath vehicles annually, it was analyzed that 14 general workers and seven skilled workers were adequate through the experiment. It was also identified that three painting process lines carried out through outsourcing were adequate. Production lead time was 201.7 hours on average and it was 230 hours maximum. To meet customer delivery service level of 95% within the deadline when establishing a customer order and vehicle delivery plan, it was analyzed that more than 215 hours of lead time is needed minimum. If the process cycle time is reduced to 85% upon system stabilization and skillfulness improvement, it was analyzed that annual output of 147 vehicles can be achieved without additional production line expansion.

• 시스템엔지니어링학술지
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• 제12권2호
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• pp.59-67
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• 2016

Recently, the increased complexity of systems has made systems engineering necessary. It is very useful for system designers to understand the whole context of the concerned system based on systems engineering. A system model can be used to describe the outcome of a system design. A system model describes the system from the viewpoint of the stakeholder's needs using the mutually exclusive and collectively exhaustive principle. A system model can be used to smoothly design a large and complicated system based on the systems engineering development process. Many companies and countries are attempting to apply model-based systems engineering, and the significance of the system model quality is increasing as system models are referenced during system development. In this paper, we propose a quality assessment method for ontology which is one of system models by focusing on the system development process. First, in this process, a system developer should explicitly show the relationship between viewpoints. Then, the system developer should select dependent rather than independent viewpoints. With dependent viewpoints, each viewpoint used to describe the system has some logical relationship. The set of viewpoints makes it possible to show, not only tangible and physical system parts, but also conceptual system parts. In this paper, we develop an ontological system model of a Japanese weather observation system. By comparing some ontological system models, we verify the effectiveness of explicitly describing the relationships between viewpoints and select dependent viewpoints.