• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.6
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• pp.48-53
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• 2002

품질보증 부분에서 대부분 통계적 수법들은 기지분포를 가정하여 데이터를 분석하고 있다. 예를 들면 공정능력에서는 정규분포를 가정하고 있고, 신뢰성 분석에서는 지수분포, 대수정규분포 또는 와이블분포 등을 가정하고 있다. 만약 이러한 것들이 가정하는 확률분포와 크게 편의될 때 도출된 결론은 그 유효성을 상실하게 된다. 따라서 공정이 정규분포를 하지 않는다면 정규분포에 기초한 공정능력지수의 사용은 부정확한 공정의 정보를 제시하게 된다. 이러한 문제를 해결하기 위하여 그 사례로 소표본일 경우 정규성의 유무를 Lilliefors 검정통계량으로 검정하였다. 그리고 최우추정량(MLE), 수정적률추정량(MME), 및 적률추정량(ME)을 사용하여 모수추정을 하여 그 각각의 경우에 공정능력지수로 평가하였다. 공정능력지수의 평가는 공정이 지수분포를 하는 경우에 적합한 공정능력지수($C_{pe}$)를 제안하고, 이것의 대안으로써 Pearson 시스템, Johnson 시스템 및 Burr 시스템과도 비교평가 하였다.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.201-207
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• 2007

In some manufacturing industries, there are many situation in which the simultaneous monitoring or control of two or more related quality characteristics is necessary. However, monitoring these two or more related quality characteristics independently can be very misleading. When several characteristics of manufactured component are to be monitored simultaneously, multivariate $x^2$ or $T^2$ control chart can be used. In this paper, establishing a early warning system(EWS) using multivariate control charts to analyze early out-of-control signals in melting process with many quality characteristics was presented. This module which we developed to control several characteristics improved efficiency and effectiveness of process control in the melting process.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.490-494
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• 2007

The chemical process plant information is used and updated during design, construction, operation, and maintenance of plant. This special type of information should be utilized as the DW(datawarehouse) which conforms to the standard format. The DW should be design in consideration of connectivity to application softwares. The application softwares are different from each other in the context of their objects such as design, management, decision-making, and so on. In this paper, some considerable facts in dealing with chemical process plant information on the framework of developing application software including datawarehousing, model building, interfacing. As a case study, the development of decision-making support system for environmental policy is illustrated for the related discussion.

• Journal of Digital Convergence
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• v.16 no.3
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• pp.225-236
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• 2018

Organizations continue to invest in the security of information technology as a means to be more competitive than others in their industry do. However, there is a relatively lack of interest in the information security compliance of employees who implement information security technologies and policies of organization. This study finds mechanisms for enhancing security compliance by applying theory of planned behavior, justice theory, and motivation theory in information security field. We use structural equation modeling to verify the research hypotheses, and conducted a survey on the employees of organization with information security policy. The results showed that organizational justice, sanction, and organizational identification affect the factors of the planned behavior theory and affect the employee's compliance intention. As a result, this research suggested directions for strategic approach for enhancing employee's compliance intention on organization's security policy.

• Journal of KIISE:Information Networking
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• v.35 no.5
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• pp.374-383
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• 2008

IEEE 802.11 WLANs support various data rates in order to adapt to wireless channel condition. It is known that when some WLAN stations use a lower data rate than the others, total throughput is considerably degraded. The concept of temporal fairness which provides equal time to all stations has been introduced to alleviate this performance anomaly problem. However, most previous mechanisms assume that stations have infinite backlogs in the MAC layer and do not consider transport layer. In this paper, we first examine and analyze the performance of previous methods considering transport layer protocols. We then propose two new temporal fairness guarantee methods: AP priority and dynamic CWmin adjustment. We carried out extensive performance study via ns-2 computer simulations. The results show that the proposed methods provide temporal fairness and improve the throughput of WLANs in various environments.

• Journal of KIISE:Information Networking
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• v.30 no.3
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• pp.437-447
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• 2003

In order to reduce the increasing packet loss rates caused by an exponential increase in network traffic, the IETF(Internet Engineering Task Force) is considering the deployment of active queue management techniques such as RED(Random Early Detection) algorithm. However, RED algorithm simple but does not protect traffic from high-bandwidth flows, which include not only flows that fail to use end-to-end congestion control such as UDP flow, but also short round-trip time TCP flows. In this paper, in order to solve this problem, we propose a simple fairness queue management scheme, called AFQM(Approximate Fair Queue Management) algorithm, that discriminate against the flows which submit more packets/sec than is allowed by their fair share. By doing this, the scheme aims to approximate the fair queueing policy Since it is a small overhead and easy to implement, AFQM algorithm controls unresponsive or misbehaving flows with a minimum overhead.

• Journal of the Korea Society of Computer and Information
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• v.14 no.3
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• pp.27-39
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• 2009

This paper describes a case study on an enterprise ontology(30) based analysis and representation of the production operation in shipbuilding. The production operation consists of steel fabrication, assembly, election, launching, sea trial and delivery process. We represent and analyze the steel fabrication process and the piping design business of the assembly process among them. First, we build an ontology on concepts of steel fabrication process and the piping design business of assembly process. And then we merge it with the original EO. We represent each process and analyze current state of production process with the merged EO and $Prot{\acute{e}}g{\acute{e}}$ plug-ins. Moreover, we can analyze dependency relations among the workflow elements. Through the case study, we have found the effectiveness of EO in business management and process management in complex heavy industries.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.05a
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• pp.176-181
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• 1999

가교 발포 공정을 거치는 대부분의 단열재의 생산 제조 공정은 혼합$\longrightarrow$압출$\longrightarrow$성형$\longrightarrow$발포$\longrightarrow$권취$\longrightarrow$포장 과 같은 공정을 거치게 된다. 생산방식에 있어서는 크게 두가치 공정에 따라 대별된다. 하나는 "인-라인" 방식의 제조공정이며 다른 하나는 "오프-라인" 방식의 제조공정이다. "인-라인"의 생산방식은 공정불량의 감지가 용이하고 재공품의 재고가 적은 장점이 있는 반면에 생산수율은 높지 못한편이다. 반면에 "오프-라인"의 생산방식은 생산수율은 상대적으로 매우 높지만 공정불량에 대한 위험이 크며 재공품의 재고가 증가하는 경향이 있다. 본 연구에서는 "인-라인" 생산방식과 "오프-라인" 생산방식의 장\ulcorner단점을 분석하여 생산되는 제품에 따라서 적절한 생산방식을 채택하여 줌으로써 회사 전체의 생산성 향상을 제고 할 수 있는 방법론을 개발하고자 한다. 이러한 문제를 해결하기 위해서 먼저 공정의 분석을 통한 수학적 모델을 제시하고 그 해법을 연구하며, 사례를 들어 설명한다.

• Journal of Intelligence and Information Systems
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• v.28 no.4
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• pp.229-250
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• 2022

This study examines the influence relationship between ESG management and organizational justice, which has become a major issue in Korean society and corporate management, and the effect of organizational justice on organizational trust, and organizational identification. In addition, the mediating effect of organizational justice in the relationship between ESG activity perception, organizational trust, and organizational identification was verified. As a result of the analysis, first, it was confirmed that the employee's perception of the company's ESG activities had a significant effect on the organizational justice. Second, it was confirmed that the employee's perception of organizational justice had a significant effect on the employee's organizational trust and organizational identification. Third, the mediating effect of organizational justice was confirmed in the relationship between employees' perception of ESG activities, organizational trust, and organizational identification. Accordingly, it is necessary to elicit positive attitudes and behaviors from employees to enhance organizational competitiveness by strengthening ESG activities, and enhancing organizational justice through Improvement of the company's institutional practices.

• ICROS
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• v.4 no.4
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• pp.11-16
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• 1998

본 고에서는 반도체 산업에서 제조 생산성 향상의 필요성을 논하였고, 생산 자동화/통합화와 제조생산성과의 관계에 대하여 기술하였다. 반도체 공정의 생산성 향상을 위해서는 우선 생산 정보시스템 Infrastructure가 구축되어야 하고 이를 기반으로 하여 각 자원 및 기능 간의 효율적인 조정이 필요하다. 특히, Moore's Law에 필요한 효율의 달성을 위해 물류시스템의 자동화/통합화 그리고 반도체 공장의 설계/운영의 합리화를 위한 노력이 종합적으로 이루어져야 한다.