• 대한조선학회논문집
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• 제45권6호
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• pp.646-655
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• 2008

A main issue about production management of shipyards is to efficiently manage the work in process and logistics. However, so far the management of a transporter for moving building blocks has not been efficiently performed. To solve the issues, optimal block transporting scheduling system is developed for minimizing of the travel distance without overload of a transporter. To implement the developed system, a hybrid optimization algorithm for an optimal block transportation scheduling is proposed by combining the genetic algorithm and the ant algorithm. Finally, to evaluate the applicability of the developed system, it is applied to a block transportation scheduling problem of shipyards. The result shows that the developed system can generate the optimal block transportation scheduling of a transporter which minimizes the travel distance without overload of the transporter.

• Steel and Composite Structures
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• 제12권3호
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• pp.231-248
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• 2012

This research aims to investigate the structural behavior of concentrically braced frames after element loss by performing nonlinear static and dynamic analyses such as Time History Analysis (THA), Pushdown Analysis (PDA), Vertical Incremental Dynamic Analyses (VIDA) and Performance-Based Analysis (PBA). Such analyses are to assess the potential and capacity of this structural system for occurrence of progressive collapse. Besides, by determining the Failure Overload Factors (FOFs) and associated failure modes, it is possible to relate the results of various types of analysis in order to save the analysis time and effort. Analysis results showed that while VIDA and PBA according to FEMA 356 are mostly similar in detecting failure mode and FOFs, the Pushdown Overload Factors (PDOFs) differ from others at most to the rate of 23%. Furthermore, by sensitivity analysis it was observed that among the investigated structures, the eight-story frame had the most FOF. Finally, in this research the trend of FOF and the FOF to critical member capacity ratio for the plane split-X braced frames were introduced as a function of the number of frame stories.

• 대한기계학회논문집
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• 제13권4호
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• pp.670-679
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• 1989

본 연구에서는 항공기 구조용 재료로서 널리 사용되는 국산 고장력 7075-T73 알류미늄 합금을 준비하고 일정진폭하중 및 단일과대하중에 의한 피로균열 진전거동에 미치는 두께의 영향과 이의 기구를 검토하였다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 추계학술대회 논문집
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• pp.73-78
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• 2002

Ships and ocean structures are generally under random loading. Various type of variable-amplitude loading affects fatigue crack growth and fatigue life. However interaction effects due to irregularity of loading including random loading have not explained exactly and it is difficult to examined fatigue crack growth behaviour and fatigue life for this reason. Therefore in this paper crack growth tests with constant-amplitude loading including a single overload were conducted to measure plastic zone size near crack tip of DENT specimen. And the observed plastic zone sized were discussed in terms of crack growth rate. As a result of this the effect the plastic rue size due to the overload is examined on the effect on crack growth rate and, consequently, fatigue life.

• 한국항해항만학회지
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• 제44권3호
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• pp.235-243
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• 2020

부산항은 컨테이너 물동량 기준으로 세계 6위의 항만이며, 환적화물 기준으로 세계 2위의 항만으로 큰 기능을 하고 있다. 그러나 항만시설 및 운송업체에 대한 정책적 배려 부족으로 부산 신항내 환적화물의 운송과 배후물류단지 화물운송에 있어 과적단속이 심각한 문제로 대두되고 있다. 이에 관련 운전자, 운송업체, 항만 배후물류단지 담당자를 대상으로 그 실태를 살펴보고, 그 문제점을 파악한 후 개선방안을 제언하였다.

• 복식문화연구
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• 제29권4호
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• pp.505-521
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• 2021

This study analyzed the effects of consumer confusion on shopping fatigue and negative purchasing behaviors in an internet shopping environment. Further, the effects of shopping fatigue on negative purchasing behaviors were analyzed. The survey was conducted among consumers in their 20s and 40s in the Seoul metropolitan area who had experience of purchasing fashion products through internet shopping. A total of 392 questionnaire were analysis, with frequency, reliability, factor, correlation, and regression analysis completed using the SPSS statistics program. The results of the study showed that consumer confusion and shopping fatigue in internet shopping environment affected negative purchasing behaviors. First, consumer confusion comprised overload confusion, similarity confusion, and ambiguity confusion. It was found that overload confusion and similarity confusion significantly affected shopping fatigue. Second, shopping fatigue significantly affected negative purchasing behaviors, and an increased level of shopping fatigue result in, increased purchase delay and non-purchase behavior. Third, consumer confusion (overload confusion, similarity confusion, ambiguity confusion) significantly affected purchase delay behavior, while similarity confusion and ambiguity confusion significantly affected non-purchasing behavior. These results will provide useful data for e-CRM and marketing directions of internet companies and will contribute to rational decision-making of internet consumers and improve the quality of consumer life.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2708-2715
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• 2021

The Multi-Purpose Overload Robot (CMOR) is a key subsystem of China Fusion Engineering Test Reactor (CFETR) remote handling system. Due to the long cantilever and large loads of the CMOR, it has a large rigid-flexible coupling deformation that results in a poor position accuracy of the end-effector. In this study, based on the Levenberg-Marquardt algorithm, the spatial grid, and the linearized variable load principle, a variable parameter compensation model was designed to identify the parameters of the CMOR's kinematics models under different loads and at different poses so as to improve the trajectory tracking accuracy. Finally, through Adams-MATLAB/Simulink, the trajectory tracking accuracy of the CMOR's rigid-flexible coupling model was analyzed, and the end position error exceeded 0.1 m. After the variable parameter compensation model, the average position error of the end-effector became less than 0.02 m, which provides a reference for CMOR error compensation.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.24-34
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• 2021

This paper predicts the speed-power-rpm relationship in regular head waves using various indirect methods: load variation, direct powering, resistance and thrust identity, torque and revolution, thrust and revolution, and Taylor expansion methods. The subject ship is KVLCC2. The wave conditions are the regular head waves of λ/LPP = 0.6 and 1.0 with three wave steepness ratios at three ship speeds of 13.5, 14.5 and 15.5 knots (design speed). In the case of λ/LPP = 0.6 at design speed, two more wave steepness ratios have been taken into consideration. The indirect methods have been evaluated through comparing the speed-power-rpm relationships with those obtained from the resistance and self-propulsion tests in calm water and in waves. The load variation method has been applied to predict propulsive performances in waves, and to derive overload factors (ITTC, 2018). The overload factors have been applied to obtain propulsive efficiency and propeller revolution. The thrust and revolution method (ITTC, 2014) has been modified.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2002년도 춘계학술발표대회 및 심포지움
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• pp.138-138
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• 2002

Oxidative stress has been associated with a number of diseases in human. Among the sources that can generate oxidative stress, it has been reported that iron can generate reactive oxygen species (ROS)with thiol. In iron overload state, increased thiol levels in plasma appeared to be associated with human mortality. In this study we examined whether iron could interact with thiols in plasma, generating ROS. In human plasma, unlike with Fe(III), Fe(II) increased lucigenin-enhanced chemiluminescence in concentration-dependent manner, and this was inhibited by SOD. Boiling of plasma did not affect chemiluminescence induced by Fe(II). Hovever, thiol depletion in plasma by pretreatment with N-ethylmaleimide (NEM)decreased Fe(II)-induced chemiluminescence significantly, suggesting that Fe(II) generated superoxide anion by the nonenzymatic reaction with plasma thiol. Consistent with this findings, albumin, the major thiol contributor in plasma, also generated ROS with Fe(II) and this generation was inhibited by pretreatment with NEM. Treatment with Fe(II) to plasma resulted un significant reduction of oxygen radical absorbance capacity (ORAC) value, suggest that total antioxidant capacity could diminished in iron overload state. In conclusion, In iron overload state, plasma may be affected by oxidative stress mediated by nonenzymatic reaction of Fe (II)with plasma thiol.

• 경영과정보연구
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• 제36권1호
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• pp.81-94
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• 2017

사물인터넷, 빅 데이터, 클라우드 컴퓨팅 등의 정보과잉시대를 맞이하여 개인의 의지와는 상관없이 데이터가 수집되고 정보가 처리된다. 연구의 목적은 개인정보과잉이 정보프라이버시 위험, 정보프라이버시 염려(수집, 통제, 인식)와 개인정보 프라이버시보호반응에 관련된 모형을 제시하고 실증분석을 하였다. 연구의 주요결과를 요약하면 다음과 같다. 첫째, 개인정보과잉은 정보프라이버시 위험에 유의한 영향을 미치는 것으로 나타났다. 둘째, 개인정보과잉은 정보프라이버시 염려(수집, 통제, 인식)에 유의한 영향을 미치는 것으로 나타났다. 셋째, 정보프라이버시 위험은 정보프라이버시 염려의 수집, 인식에 유의한 영향을 미친 반면, 통제는 유의한 영향을 미치지 않는다. 이러한 결과는 정보과잉으로 인한 개인정보가 개인의도와 다르게 정보가 다른 방향으로 이용될지도 모른다는 것이다. 정보위험을 개인정보사용자는 정보의 수집과정에서 인지하고 있음을 알 수 있다. 정보에 대한 통제는 개인정보사용자가 가능하지 않는 것으로 판단되어, 정보프라이버시 염려(통제)는 유의한 영향을 미치지 않는 것으로 나타났다. 넷째, 정보프라이버시 염려(수집, 인식)는 정보프라이버시 보호반응에 유의한 영향을 미치는 것으로 나타났으나, 정보프라이버시(통제)는 유의한 영향을 미치지 않는 것으로 나타났다. 결론적으로 개인정보사용자는 개인정보과잉으로 인해 정보침해를 염려하고 있으며, 자신의 정보에 대한 보호능력이 강해질 것이다.