• 소음진동
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• 제6권1호
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• pp.71-82
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• 1996

The finite element analysis for rotor bearing systems has been an essential tool for design, identification, and diagnosis of rotating machinery. Among others, the unbalance response analysis is fundamental in the vibration analysis of rotor bearing systems because rotating unbalance is recognized as a common sourve of vibration in rotating machinery. However there still remains a problem in the aspect of computational efficiency for unbalance response analysis of large rotor bearing systems. Gyroscopic terms and local bearing parameters in rotor bearing systems often make matters worse in unbalance response computation due to the complicated dynamic properties such as rotational speed dependency and/or anisotropy. The present paper proposes an efficient method for unbalance responses of multi-span rotor bearing systems. An improved substructure synthesis scheme is introduced which makes it possible to compute unbalance responses of the system by coupling unbalance responses of substructures that are of self adjoint problem with small order matrices. The present paper also suggests a scheme to easily deal with gyroscopic tems and local, coupling or bearing parameters. The proposed method causes no errors even though the computational effort is reduced drastically. The present method is demonstrated through three test examples.

• 한국의류산업학회지
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• 제21권3호
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• pp.318-325
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• 2019

This study analyzes current self-nail tips and nail-tip satisfaction. The study method selected from 3 domestic and 3 overseas companies analyzed current self-nail tips based on brand recognition and sales rate. A questionnaire was conducted on 261 adult women in their 20s and 50s about the satisfaction of nail care and self-nail tips. The results are as follows. As a result to analyze the current nail tips, there were products that did not contain the type of nail tip or the composition and ingredients of the glue. An online survey of the sizes of the current nail tips indicated differences in the sizing system method and that the presented sizes are different. The response rate was the highest for the survey results on why self-nail tips were preferred for respondents who prefer self-nail tips because the price was cheap. The reason why they did not prefer self-nail tips was that the degree of completeness was lower and the fitness was not good. In addition, it showed a high response rate in that the adhesive strength was poor and the size did not fit the nails. Therefore, it is necessary to develop a size for nail types by ergonomic design and develop a self-nail tip that can reduce nail damage.

• 한국식품영양학회지
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• 제29권1호
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• pp.104-114
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• 2016

In this study, we investigated protection motivation and behavioral intention to prevent serious illnesses related to excessive sodium intake among the university students in Gyeongnam and Busan. Within the protection motivation theory (PMT) framework, a survey questionnaire was developed to measure participants' perceptions on the severity of and the vulnerability to the threat of serious diseases due to the high sodium intake as well as the effectiveness of preventive measures (response efficacy), and the ability to perform them (self-efficacy) along with their willingness to follow recommendations (behavioral intention). Data was collected in June 2015. Study participants were divided into either low (n=117) or high (n=177) sodium intake behavior groups based on their current behaviors. Exploratory factor analysis was performed to measure construct validity and Cronbach's alpha was calculated to check reliability of measurement items. The high sodium intake behavior group perceived higher vulnerability than the low sodium intake behavior group among four PMT factors. Differences of the other three factors were not significant between the two groups. The results of hierarchical regression analysis indicated that self-efficacy and response efficacy affected behavioral intention of high sodium intake behavior among students. Hence, development of strategies to increase self-efficacy and response efficacy are strongly recommended.

• 한국의류산업학회지
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• 제6권5호
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• pp.595-604
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• 2004

This study is to investigate complaining behavior of consumers who purchase fashion products on the internet, as well as to find how the complaining behaviors are related to the consumers' characteristics. The subjects of this study are limited to the consumers who have experienced dissatisfaction when purchasing fashion products through the internet. The questionnaires were administered to male and female respondents using the internet shopping mall. The results can be summarized as follows: The factor analysis shows that consumer complaining behaviors are fitted well into four factors(direct complaining behavior, private complaining behavior, third-party complaining behavior, and no response). In the difference analysis by consumer's complaining behavior styles and gender, private complaining and third-party complaining behavior were significant statistically. In the difference analysis between consumer's complaining behavior styles and internet self-efficacy. Internet self-efficacy was significantly different according to consumer's complaining behavior styles, especially for direct complaining, third-party complaining and no response. Private complaining behavior, third-party complaining behavior and no response were negatively related to consumer retention, while direct complaining behavior was not.

• 한국정보통신학회논문지
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• 제12권1호
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• pp.122-129
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• 2008

기동 시나 갑작스런 토크명령 변동에 빠른 토크응답 특성을 갖는 퍼지 논리 제어기를 이용한 농형 유도 전동기의 직접 토크제어 방식을 제안하였다. 퍼지 제어 알고리즘은 기존의 DSC(Direct Self Controller) 제어 원리를 기저로 하여 제안하였으며 퍼지 추론 및 비 퍼지화를 거쳐 수행된다. 유도전동기의 자속과 토크는 광범위한 속도 영역에서 비 간섭 및 우수한 동특성을 갖는 회전자 자속 기준 동특성 모델을 사용하였다. 실험 결과 제시한 퍼지 제어 알고리즘은 우수한 동특성 및 적응적 특성을 갖으며 전동기 변수와 동작 조건의 변동에 민감하지 않고 강인하다.

• Steel and Composite Structures
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• 제37권6호
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• pp.679-693
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• 2020

This paper investigates the seismic response of buildings equipped with Self-Centering Energy Dissipating (SCED) braces. Two-dimensional models of 3, 6, 12 and 16-story SCED buildings considering both material and geometric nonlinearities are investigated by carrying out pushover and nonlinear time-history analyses. The response indicators of the buildings are studied for weight-scaled ground motions to represent the Design Basis Earthquake (DBE) level and the Maximum Considered Earthquake (MCE) event. The fragility curves of the buildings for two Immediate Occupancy (IO) and Life Safety (LS) performance levels are developed using Incremental Dynamic Analysis (IDA). Results of the nonlinear response history analyses indicate that the maximum inter-story drift occurs at the taller buildings. The mean peak inter-story drift is less than 2% in both hazard levels. High floor acceleration peaks are observed in all the SCED frames regardless of the building height. The overall ductility and ductility demand increase when the number of stories reduces. The results also showed the residual displacement is negligible for all of case study buildings. The 3 and 6-story buildings exhibit desirable performance in IO and LS performance levels according to fragility curves results, while 12 and 16-story frames show poor performance especially in IO level. The results indicated the SCED braces performance is generally better in lower-rise buildings.

• BMB Reports
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• 제55권2호
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• pp.57-64
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• 2022

Autoimmune disease is known to be caused by unregulated self-antigen-specific T cells, causing tissue damage. Although antigen specificity is an important mechanism of the adaptive immune system, antigen non-related T cells have been found in the inflamed tissues in various conditions. Bystander T cell activation refers to the activation of T cells without antigen recognition. During an immune response to a pathogen, bystander activation of self-reactive T cells via inflammatory mediators such as cytokines can trigger autoimmune diseases. Other antigen-specific T cells can also be bystander-activated to induce innate immune response resulting in autoimmune disease pathogenesis along with self-antigen-specific T cells. In this review, we summarize previous studies investigating bystander activation of various T cell types (NKT, γδ T cells, MAIT cells, conventional CD4⁺, and CD8⁺ T cells) and discuss the role of innate-like T cell response in autoimmune diseases. In addition, we also review previous findings of bystander T cell function in infection and cancer. A better understanding of bystander-activated T cells versus antigen-stimulated T cells provides a novel insight to control autoimmune disease pathogenesis.

• 경영과정보연구
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• 제39권1호
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• pp.75-91
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• 2020

본 연구는 소비자 공감반응의 여러 가지 측면에 대한 이론적 근거를 바탕으로 소비자 스스로가 자기 공감화하는 과정으로 확장할 수 있는지에 대한 문제제기와 함께 탐색적 차원에서 심층면접을 적용하여 확인하고자 하였다. 소비자 공감과 관련된 대부분의 연구들은 공감이론을 바탕으로 소비자 공감의 반응적 차원을 이성적, 감성적 차원으로 구분을 하고 있으며, 현재의 관점에서 제시되는 자극에 국한하여 소비자가 지각하는 공감적 반응을 살펴보고 있다는 특징이 있다. 하지만 본 연구에서는 여기서 한 단계 더 나아가 소비자 스스로가 해당 콘텐츠에 대하여 재생산 및 재개발 과정의 창조적 거리를 형성하는 자기공감화의 과정으로 나아감으로써 궁극적으로 자아성찰 단계로 나아갈 수 있음을 확인하고자 하였다. 심층면접을 통한 탐색적 연구결과, 특정 마케팅 자극에 대한 소비자의 공감적 반응은 선행연구들이 강조하고 있는 차원과 함께 보다 창조적이고 자기공감적 차원에서도 존재하고 있음이 간접적으로 확인되었다. 이러한 연구결과를 바탕으로 본 연구에서는 소비자 공감적 반응은 단순히 하나의 단일차원을 넘어 다차원적 구조를 형성함과 동시에 공감적 자기화의 확장적 구조로 나아갈 수 있음을 확인할 수 있었다. 이는 소비자의 공감적 반응이 특정 차원으로 설명되기보다는 공감적 반응의 연속성 측면에서 총체적으로 파악해야 함을 시사한다. 본 연구가 탐색적인 성격의 초기 연구로서 의의를 가지지만 여러 가지 내용적 타당성의 보완 및 연구방법의 정교화는 후속연구를 통하여 보완을 해야 할 것으로 사료된다. 본 연구를 통하여 소비자 공감의 반응이 타인공감을 넘어 창조적 차원의 자기공감으로 확장될 수 있다는 이해의 폭이 확장됨과 동시에, 향후 이와 관련된 많은 후속 연구들이 파생될 것으로 기대된다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.553-556
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• 2000

The paper deals with the dynamic response of non-uniform beams subjected to a moving mass. In the dynamic analysis, the effects of inertia force, elastic force, centrifugal force, Coriolis force and self weight due to moving mass are taken into account. Galerkin's mode summation method is applied for the discretized equations of notion. Numerical results for the dynamic response of the non-uniform beam under a moving mass having various magnitudes and velocities are investigated. Experimental results have a good agrement with predictions

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.505-505
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• 2000

Controlling the process by PID controller is widely used in industry by applying Ziegler-Nichols method in analyzing parameter of the controller. However, in fact. it is still necessary to tune parameter in order to obtain the best process response. This paper presents a Self-Tuning PID controller utilizes the personal computer to synthesize and analyze controller parameter as well as tune for appropriate parameter by using Dahlin method and Extrapolation. Experimental results using a Self-Tuning PID controller to control water level and temperature, it is found that the controller being developed is able to control the process very effectively and provides a good response similar to the controller used in the industry.