• 해양환경안전학회지
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• 제2권1호
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• pp.143-143
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• 1996

Recent Class requirements and IMO recommendations concerning Hull Strength Monitoring (HSM) have prompted an increasing number of shipowner to adopt monitoring systems on bulk carriers and tanker. Such systems are designed to give warning when stress levels and the frequency and magnitude of ship motions approach levels which require corrective action. When fitted these systems provide enhanced operational safety and efficiency. This paper describes a development beyond the standard BMT HSM system through the integration of stress, motion and radar-based sea state monitoring with powerful, on-board, artificial intelligence (AI) tools. The latter utilises conceptual clustering techniques as an aid to pattern recognition in stress, fatigue. motion and sea state data clusters. This, in turn, provides additional operational guidance for ship's staff. Feedback from applications of the standard BMT HSM and extended HSM systems on board the British Steel Bulk Shipping fleet is described.

• 대한산업공학회지
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• 제24권3호
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• pp.359-365
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• 1998

An economic process monitoring procedure is presented when the major quality characteristic of the item is dichotomous. Every item is inspected and decided whether it is conforming or not. If an item is found to be nonconforming, the previous number of the successive conforming items is compared with a predetermined number r to check the process for existence of any assignable cause of variation. A cost model is constructed on the basis of costs of inspection, illegal signal, undetected out-of-control state and corrective action. By minimizing the expected total cost per unit time, the optimal value of r is obtained. The effects of cost coefficients are studied numerically.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권1호
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• pp.1-11
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• 2011

• 한국신뢰성학회지:신뢰성응용연구
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• 제13권3호
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• pp.175-190
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• 2013

This study considers reliability growth management as the excellent method for construction equipment development with the effect on decreasing COPQ(Cost of Poor Quality Cost) of new products. MIL-HDBK-189A(1981) and RADC-TR-84-20(1984) standards provide a general concept of reliability growth management including to reliability growth test, models and FRACAS(Failure Reporting and Corrective Action System). There is no study how to apply reliability growth management to construction equipment(or machine) development. This paper propose the method to apply it to construction equipment development process from the reliability target setting for developing products to launching them at market. It is expecially showing how to set target reliability for new developing equipment and the development risk to reach the reliability target in detail.

• 한국정밀공학회지
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• 제10권3호
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• pp.175-181
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• 1993

In this paper, a practical method to generate task strategies applicable to chamferless and high-precision assembly, is proposed. The difficulties in devising reliable assembly strategies result from various forms of uncertainty such as imperfect knowledge on the parts being assembled and functional limitations of the assembly devices. In approach to cope with these problems, the robot is provided with the capability of learning the corrective motion in response to the force signal trrough iterative task execution. The strategy is realized by adopting a learning algorithm and represented in a binary tree type database. To verify the effectiveness of the proposed algorithm, a series of simulations and experiments are carried out under assimilated real production environments. The results show that the sensory signal-to-robot action mapping can be acquired effectively and, consequently, the chamferless assembly can be performed successfully.

• 한국가스학회지
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• 제10권3호
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• pp.20-26
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• 2006

본 연구에서는 교량에 부착된 도시가스 배관 53개소에 대해 현장조사를 실시하고 위해요인이 발생할 우려가 있는 도시가스배관 대해 구조해석 프로그램을 이용한 응력분석을 실시하고 취약부위에 대한 현장 응력 측정을 통해 배관에 미치는 응력에 관한분석을 실시하여 가스배관의 안전성을 평가하고자 했다. 현장 안전진단의 결과는 일차적으로 선정된 대상 10개소 중 가장 응력적으로 취약할 것으로 판단되는 2개소에 대해 현장 응력측정을 통한 진단을 수행하였다. 안전계수 2를 고려한 배관 최대 지지응력의 70% 이상 수준의 응력이 부가되는 것으로 나타났다. 보수시점을 넘어선 교량첨가배관에 대해 응력 해소 공사, 지지대 보수 및 교체 공사를 통해 부가되는 응력을 해소하였다. 현장진단 결과로 나타난 바와 같이 장기간 경과된 배관에서도 견고한 고전으로 발생하는 응력은 보수를 통하여 해소해줌으로 안전성을 확보할 수 있었다.

• 한국언론정보학보
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• 제59권
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• pp.180-210
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• 2012

이 연구의 목적은 우리나라에서 이루어진 2000년대 10년간의 사과문 분석을 통하여 우리나라 사람들이 어떤 위기 커뮤니케이션 전략을 사용하고 있는지 실제적인 상황 진단을 내려 보는 것이다. 이를 위해 기존 문헌에서 사용된 사과전략의 유형과 우리나라 사과문에서 독 특하게 발견된 사과 유형을 탐색하여 분석에 이용하였다. 또한 조직별, 위기 유형별, 위기진행시기별로 각각 다르게 나타나는 위기 커뮤니케이션 전략을 세부적으로 알아보았다. 분석 결과 위기 커뮤니케이션 전략 중 사과 전략과 수정행위 전략이 가장 많이 사용되고 있었으며, 입지 강화와 동정심유발 전략이 그 뒤를 이었다. 조직별, 위기 유형별, 위기 진행시기별로도 선호되는 위기 커뮤니케이션 전략에 차이가 있었는데, 정부나 공적기관의 경우, 위기의 책임성이 내부에 있는 경우 및 통제력이 있다고 여겨지는 인문사회위기인 경우 정당화 전략을 선호하는 경향이 나타났다. 이와 같은 결과는 우리나라의 문화적 특징인 정, 체면 의식과 관련되어 있는 것으로 보인다. 즉 광범위한 의미에서 간접적 수정행위 전략, 초월 전략 등은 일종의 체면유지 전략으로 이해될 수 있으며, 입지강화나 동정심 유발은 인정에 호소하는 전략이라고 해석할 수 있다. 향후 연구에서는 이러한 우리나라의 문화적 특징을 반영한 새로운 위기 커뮤니케이션 유형화와 함께 그것의 효과를 입증하는 실증연구가 이루어져야 할 것으로 보인다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권1호
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• pp.32-41
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• 2011

By using a newly developed Korean risk-based corrective action (K-RBCA) software (K-RBCA) and the RBCA Tool Kit, risk assessment was performed on a site that was contaminated with aromatic hydrocarbons and heavy metals. Eight chemicals including benzene, ethylbenzene, xylenes, naphthalene, benz(a) anthracene, benzo(b) fluoranthene, benzo(a) pyrene, and arsenic that exceeded the US EPA Soil Screening Level were chosen as the target pollutants. A conceptual site model was constructed based on the site-specific effective exposure pathways. According to the RBCA Tool Kit the carcinogenic risk of arsenic was larger than $10^{-6}$, which is the generally acceptable carcinogenic risk level. The K-RBCA estimated the same level of carcinogenic risk for arsenic. With the RBCA Tool Kit, the carcinogenic risk of benzo(a) pyrene was estimated to be about $1.3{\times}10^{-6}$. However, with the K-RBCA benzo(a) pyrene did not exhibit any risk. The inconsistency between the softwares was attributed to the different fundamental settings (i.e., medium division) between the two softwares. While the K-RBCA divides medium into surface soil, subsurface soil, and groundwater, the RBCA Tool Kit divides medium into only soil and groundwater. These differences lead to the different exposure pathways used by the two softwares. The K-RBCA considers the exposure pathways in surface soil and subsurface soil separately to estimate risk, however, the RBCA Tool Kit considers the surface soil and subsurface soil as one and uses the integrated exposure pathways to estimate risk. Thus the resulting risk is higher when the RBCA Tool Kit is used than when the K-RBCA is used. The results from this study show that there is no significant difference in the risks estimated by the two softwares, thus, it is reasonable to use the K-RBCA we developed in risk assessment of soil and groundwater. In addition, the present study demonstrates that the assessor should be familiar with the characteristics of a contaminated site and the assumptions used by a risk assessment software when carrying out risk assessment.

• 대한인간공학회지
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• 제26권1호
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• pp.39-46
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• 2007

The purpose of this study was to develop a comprehensive posture classification scheme considering the effects of external load and motion repetition as well as those of working posture. The scheme was developed based on a series of existing empirical studies dealing with postural classification scheme, effects of external load and motion repetition. Ranges of joint motions, external load and motion repetition were divided into the groups with the same degree of discomforts. Each group was assigned a numerical relative discomfort score of code on the basis of discomfort values for the neutral position of elbow flexion. The criteria for evaluating stress of working postures were proposed based on the four distinct action categories, in order to enable practitioners to apply appropriate corrective actions. The proposed scheme was compared with OWAS, RULA and REBA. The comparison revealed that while the proposed scheme and RULA showed similar results for the working postures with light external load and non-repetitive postures, the former overestimated postural load for postures with moderate or heavy external load and repetitive postures than the latter.

• 대한인간공학회지
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• 제25권2호
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• pp.43-50
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• 2006

The purpose of this study was to investigate applicability of NIOSH lifting equation(NLE) to analysis of workload for patient transferring. In principle, the NLE is not applied to analyzing workload of patient transferring, because 1) the task is generally performed by two or more persons; 2) unlike ordinary objects, human body of patients is basically unstable load with their location of the center of mass significantly varying during lifting activity; and 3) the task is done in a restricted work space. This study was conducted through comparison of NIOSH lifting indexes(LIs) and L5/S1 compressive forces by 3DSSPP for patient transferring tasks performed by 2~6 persons. The results showed that LIs are linearly correlated with L5/S1 compressive forces with correlation coefficient of 0.92, which resulted in a significant simple linear regression equation for LIs and L5/S1 compressive forces. Consequently, it was concluded that the NLE is applicable to transferring patient only with slight modification. Based on the results, instead of 1.0 originally used by NIOSH, the LI of 1.5 was proposed as a gauge to estimate whether or not the task needs corrective action to reduce risk for developing lifting-related low back pain.