• 한국정밀공학회지
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• 제33권5호
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• pp.419-425
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• 2016

A powder spreading phenomenon is one of disadvantageous characteristics of the powder bed fusion process using electron beams. The powder spreading phenomenon can be controlled using a pre-heating process of metallic powders. The aim of this paper was to investigate the preheating process of Stellite21 powder using electron beams. Powder spreading experiments were performed to examine the influence of process parameters on the spreading behaviors of Stellite21 powder. Powder heating experiments were carried to investigate the effects of the focusing current of the electron beam on the quality of the heated region. Using the results of the powder spreading and heating experiments, an appropriate combination of process parameters was obtained. The pre-heating experiment of Stellite21 was performed using the estimated combination of process parameters. The results of preheating experiments showed that the preheated Stelllite21 layer with desired characteristics can be created when the estimated combination of process parameters is applied.

• 산업경영시스템학회지
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• 제34권4호
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• pp.114-119
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• 2011

Process capability indices (PCls) have been widely used in manufacturing industries to provide a quantitative measure of process potential and performance. The previous studies have measured only one location on each part in the case of single variate. To calculate the reliable process capability, a couple of measuring locations on each part are required. In this paper, we propose a new system process capability index $SC_{pm}$ (m) which is the minimum value of the location PCls.

• 동력기계공학회지
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• 제16권2호
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• pp.49-53
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• 2012

Thermal spray coatings developed by deposition of splats, it formed by impacting molten droplets on substrates during thermal spray process. In this study, the Ni-based coatings were fabricated by thermal spray process with two different process parameters, oxygen gas flow and acetylene gas flow, with three different levels of each parameters. The morphology of splats and microstructure were observed by optical microscope. Hardness test were performed on the Ni-based coatings. It was confirmed that process parameters of thermal spray process have effect in morphology of splats. These effects also have important implications on the deposit microstructure and properties of Ni-based coatings.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.664-667
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• 2000

Although managing knowledge about business processes has been recognized as an important aspect of Knowledge Management System (KMS), it has not been satisfactorily addressed academically or commercially. This paper proposes a KMS architecture to effectively manage business process as knowledge. It expands commonly recognized KMS functions with the process packaging module that defines business processes, monitors and evaluates process instances, keeps process instance history, and provides link between processes and other knowledge items such as documents and experts. The users can not only find the best practice of a business process but also learn from mistakes. A prototype system is implemented to show the feasibility of the proposed architecture. The results of this paper can contribute to expand current KMSs to help use knowledge to enhance the users' performance in their business processes.

• 시스템엔지니어링학술지
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• 제12권2호
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• pp.29-38
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• 2016

The threats around Korea Peninsula have been dramatically increased because North Korea is developing the Nuclear ballistic missile, Submarine launched ballistic missile(SLBM), and many kinds of weapons for sudden provocations. Therefore, ROK navy needs the cutting-edge warship combat systems in order to defeat the enemy threats effectively in the sea. The paper analyzes current warship combat system acquisition process and studies US navy and other advanced countries acquisition process and their contraction trends. After that, the paper proposes the optimal acquisition process of warship combat system for the ROK navy based on our current situation and other advanced countries acquisition trends. The paper will dedicate the next generation warship combat system acquisition process.

• Coupled systems mechanics
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• 제5권1호
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• pp.21-39
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• 2016

Wastewater process models are the essential tools for understanding relevant aspects of wastewater treatment system. Wastewater process modeling provides more options for upgrades and better understanding of new plant design, as well as improvements of operational controls. The software packages (BioWin, GPS-X, Aqua designer, etc) solve a series of simulated equations simultaneously in order to propose several solutions for a specific facility. Research and implementation of wastewater process modeling in combination with computational fluid dynamics enable testing for improvements of flow characteristics for WWTP and at the same time exam biological, physical, and chemical characteristics of the flow. Application of WWTP models requires broad knowledge of the process and expertise in modeling. Therefore, an efficient and good modeling practice requires both experience and set of proper guidelines as a background.

• 시스템엔지니어링학술지
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• 제2권2호
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• pp.21-26
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• 2006

In modern systems technology, increasingly more systems are anticipated to operate in real-time environment. These systems are usually complex to implement since it is not easy to satisfy the real-time requirement for both hardware and software components simultaneously. In this paper, we first review an object-oriented development process that was proposed earlier for software-intensive real-time system using the Unified Modeling Language (UML). We then study how to improve the problems that the UML approach might have. Applying the systems engineering(SE) process yields useful results which include : 1) an improved requirements management over the whole system life-cycle ; 2) a detailed scenario on how to carry out the SE process ; and 3) a conversion process from the text-based requirements to the UML-based graphic ones.

• 한국막학회:학술대회논문집
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• 한국막학회 2005년도 추계 총회 및 학술발표회
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• pp.231-233
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• 2005

• Design & Manufacturing
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• 제9권1호
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• pp.18-22
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• 2015

Mold making and product manufacturing process was made by a die through a number of stages. Thereby, it takes a long period of time from the manufacture of mold until passed the products to consumers. However, it is not possible to meet the diverse desires purchasing of consumer. We made a 3D CAD Model aligned with product scan data using reverse engineering. Utilizing thereafter flow analysis to derive the optimal mold conditions, by applying the condition, and devised a mold fabrication process that is much shorter than the conventional process for fabricating a mold. In this study, the outlet cover to the product, it describes a process, as a result, it was confirmed that the number of steps can be shortened much more than the conventional process.

• 시스템엔지니어링학술지
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• 제12권2호
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• pp.1-8
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• 2016

The system engineering should be actively applied to successfully develop a complex and advanced weapon system, because the system engineering uses a multidisciplinary approach. Therefore, this study proposed a system engineering process for a successful weapon system development. According to the national standard policy, an IPT aspect system engineering standard must adapt the ISO/IEC/IEEE 15288. It also asks for tailoring with considering the IPT characteristics as a weapon system acquisition institution. The IPT aspect system engineering process to acquire a weapon system can be expressed with 3 process groups (Agreement, Technical Management, Technical) and 20 processes. There was a need for an institutional framework to hire retired experts from related organizations as consultants to apply the low-cost and high efficiency system engineering in the weapon system acquisition field.