• International Journal of Quality Innovation
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• 제7권3호
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• pp.107-115
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• 2006

Control charts are important tools of statistical quality control. In 1956, Duncan first proposed the economic design of $\bar{x}-control$ charts to control normal process means and insure that the economic design control chart actually has a lower cost, compared with a Shewhart control chart. An moving average (MA) control chart is more effective than a Shewhart control chart in detecting small process shifts and is considered by some to be simpler to implement than the CUSUM. An economic design of MA control chart has also been proposed in 2005. The weaknesses to only the economic design are poor statistics because it dose not consider type I or type II errors and average time to signal when selecting design parameters for control chart. This paper provides a construction of an economic-statistical model to determine the optimal parameters of an MA control chart to improve economic design. A numerical example is employed to demonstrate the model's working and its sensitivity analysis is also provided.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2005년도 추계학술대회 및 정기총회
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• pp.213-216
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• 2005

In this research, we explore how to manage the transition of technology generations considering incremental innovation of the existing technology generation. Firms can slow down decaying of the existing technology by continuous incremental improvements rather than introducing a new generation technology at the first time if the former strategy is better. We characterize optimal technology transition problem by setting up an optimal control model. The model which is originally designed and solved by Thompson(1968) as a ‘Machine maintenance problem’ has been cited to build the main body of our model. With this analytical model, we derive optimal ‘incremental innovation’ strategy which is considering transition to the next technology. Our analysis indicates that there exists an unique ‘stopping incremental innovation timing’. Before the point of time, the decision maker should make his effort at a maximum level to enhance the current technology. However from the stopping timing to the final time horizon where the new technology is introduced, it is found that not to invest to the current technology any more is optimal.

• 산업경영시스템학회지
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• 제33권3호
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• pp.93-101
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• 2010

Regarding project management, many organizations have developed and distributed general project management knowledge systems, and application fields use the knowledge systems to apply the process suitable for characteristics of a project. This study suggests project management process models to apply to product development projects and introduces the application cases. This product development project management process model is composed of five top processes of initiation and preparation, planning, implementation management, control, and termination and transfer. The five processes are re-divided into 18 bottom processes. These processes are expressed as input, control, output, and mechanism by using the IDEF0 model. This model is applied to the new car development project of a Korean automobile company and introduces the cases, which shows a project charter, a work breakdown structure, a project schedule, a progress s-curve, a risk register, and a performance report.

• Asia pacific journal of information systems
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• 제15권1호
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• pp.115-133
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• 2005

This study is to develop an information security management model(ISMM) for small and medium sized enterprises(SMEs). Based on extensive literature review, a five-pillar twelve-component reference ISMM is developed. The five pillars of SME's information security are: centralized decision making, ease of management, flexibility, agility and expandability. Twelve components are: scope & organization, security policy, resource assessment, risk assessment, implementation planning, control development, awareness training, monitoring, change management, auditing, maintenance and accident management. Subsequent survey designed and administered to expose experts' perception on the importance of these twelve components revealed that five out of tweleve components require relatively immediate attention than others, especially in SME's context. These five components are: scope and organization, resource assessment, auditing, change management, and incident management. Other seven components are policy, risk assessment, implementation planning, control development, awareness training, monitoring, and maintenance. It seems that resource limitation of SMEs directs their attention to ISMM activities that may not require a lot of resources. On the basis of these findings, a three-phase approach is developed and proposed here as an SME ISMM. Three phases are (1) foundation and promotion, (2) management and expansion, and (3) maturity. Implications of the model are discussed and suggestions are made for further research.

• 한국경영정보학회:학술대회논문집
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• 한국경영정보학회 2007년도 추계학술대회
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• pp.117-122
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• 2007

Recently, as the management environments are changing rapidly and the uncertainty is becoming larger, the needs of internal control for management and IS become stronger. In order to construct a new internal control system for IS, it is necessary to evaluate the former research of the system. This study emphasizes the importance of effective internal control system, presents a conceptual framework for the preceding factors to consider, and verifies empirically the framework. This study sets the organization citizenship behavior, IS innovation resistance, and IT capability from the viewpoint of Socio-Technical system as the preceding factors for the effectiveness of internal control system. A research model, affecting the above factors on IS capability as a mediating variable of the internal control effectiveness for the use of IS, is set up. PLS-Graph 3.0 is used to verify the model. We found that the internal control effectiveness have affirmative effect on information capability, a surrogate variable of the IS effectiveness and a mediation effect is meaningful.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1993년도 추계학술대회발표논문집; 서강대학교, 서울; 25 Sep. 1993
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• pp.31-39
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• 1993

This paper considers a procedure for the economic design of a cumulative score(CUSCORE) control chart and more sensitive than X-type control chart for small shift to control the mean of a process with a exponentially distributed quality characteristic. An expected loss - cost model as a function of design variables(sample size, sampling interval, scoring limit and decision limit) is derived. Direct search techniques are used to optimize the model subject to ARL in control. Numerical examples and sensitivity analysis of the model are presented. For selected values of situation parameters a comparison study with CUSUM charts is given. CUSCORE control charts compare favourably with CUSUM charts in cost for speedy production process. The proposed control chart can be directly applied for controlling the lifetime characteristics.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1216-1222
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• 2009

Ecological Engineering (EE) refers to all sustainable engineering that can reduce damage to ecosystems and that adopts ecology as a base and safety as an orientation in order to implement conservation of biodiversity and sustainable development. In short, EE attempts to safeguard the ecological environment while any essential construction projects proceed. EE encompasses many fields, including construction skills, ecosystem preservation, landscape, and even related cultures and so on. Such variety results in greater complexity of construction, and, consequently, indirectly increases the difficulty of construction quality control. The objective of our research is to explore a promising model for EE via an extensive literature survey. This model includes three principal stages: plan-design, construction, and maintenance, along with individual accompanying phases concerned with quality control and vital management. In this article, a river restoration example is adopted to describe in detail the critical points of quality control in the three stages (plan-design, construction, and maintenance) of the construction life cycle. This study proposes an integrated structure for quality management of EE to guarantee its quality and to enhance its core applications in order to achieve long-lasting preservation of the environment.

• 인터넷정보학회논문지
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• 제10권4호
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• pp.177-187
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• 2009

기존의 RFID 장치 관련 응용들은 사용자가 RFID 태그 또는 리더를 제어 관리할 수 있도록 지원하는 인터페이스를 특정 장치 벤더에 종속적인 형태로 제공하고 있다. 또한 기존의 RFID 비즈니스 응용들은 RFID 리더 또는 미들웨어 시스템들이 제공하는 고유의 태그 이벤트 데이터 포맷에 의존적으로 구현되고 있다. 따라서 RFID 인프라 관리자들은 관리 대상 태그, 장치 및 시스템들에 대한 개별적인 제어 관리 규격을 반드시 이해하고 있어야 하는 어려움을 가진다. 이와 더불어 현재 대부분의 RFID 응용서비스들은 태그 아이템의 실시간 정보 가시화 및 비즈니스 스텝 추적과 같은 단순 정보 제공에 국한된 한계를 가지고 있다. 이와 같은 문제들을 해결하기 위하여, 본 논문에서는 벤더마다 상이한 인터페이스 규격을 가지는 이기종 RFID 장치, 미들웨어 및 다양한 유형의 응용들에 대한 통합적인 제어 관리 방법을 기술할 수 있는 RFID 서비스 관리 정책 모델을 제안한다. 또한, 본 논문에서는 제안 모델을 기반으로 정의된 RFID 서비스 관리 정책이 특정 RFID 하부 인프라에 적응적으로 변환 및 처리되는 과정을 예제 시나리오를 통해 설명한다.

• 대한인간공학회지
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• 제36권3호
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• pp.221-230
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• 2017

Objective: The purpose of this study is to draw the accident prevention model using the signal detection theory, and to implement accident prevention program, based on a health promotion and support activities in a shipbuilding company. Background: Workers' health management is perceived important from the human resource management perspective, as well as from the personal perspective. Method: This study developed an accident prevention model by analyzing the correlation between 704 workers' health examination variables, and reviewed the verification of the model through a follow-up survey on the control variables and status of hazards targeting 650 workers for four years from 2007 to 2010. Also, a health promotion program was implemented targeting a production division to improve alcohol habits, smoking, musculoskeletal pain complaints and hearing control indices, which are the control variables of the model. Results: As a result of four years' implementation, the following effects were obtained: the days away from work fell 87.5%, and accident rate dropped 71.5% in 2010, respectively, compared to 2006, before the activity was implemented. Conclusion: This study shows that the accident prevention activities based on workers' health promotion activities are effective to prevent industrial accidents and injuries. Application: The research findings will serve as a practical guideline for establishing preventive measures in the shipbuilding company.

• Journal of Electrical Engineering and Technology
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• 제9권5호
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• pp.1729-1738
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• 2014

The offline verification of state of charge estimation, power estimation, fault diagnosis and emergency control of battery management system (BMS) is one of the key technologies in the field of electric vehicle battery system. It is difficult to test and verify the battery management system software in the early stage, especially for algorithms such as system state estimation, emergency control and so on. This article carried out the virtual environment modeling for verification of battery management system. According to the input/output parameters of battery management system, virtual environment is determined to run the battery management system. With the integration of the developed BMS model and the external model, the virtual environment model has been established for battery management system in the vehicle's working environment. Through the virtual environment model, the effectiveness of software algorithm of BMS was verified, such as battery state parameters estimation, power estimation, fault diagnosis, charge and discharge management, etc.