• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.780-785
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• 2004

The work presented here deals with controller design by graphical method based on proportional control ramp response. The design aims at the improvement of transient response, disturbance rejection capability, steady-state error reduction with stability preservation. The first step is to generate tracking-error curve with proportional control only and decide the added error signal shape on the error curve. The effectiveness of the proposed controller is confirmed through the simulation and experiment.

• 실천공학교육논문지
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• 제13권3호
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• pp.507-514
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• 2021

본 연구에서는 K대학교 공과대학에서 학위 연계형 일학습병행제 학습근로자들에게 최초로 학위를 수여한 2020년 2월 졸업자를 대상으로 이루어진 조별 졸업 작품 제작과 그 결과를 공학 논문 체계로 완성하는 단계까지 진행한 과정을 제시하고, 대상자들에게서 얻어진 39개 항목의 설문조사 결과를 같은 학년도 졸업자인 같은 전공의 전일제 학생들의 결과들과 비교 분석하였다. 5개 대표 응답 문항을 집단별로 구분하여 통계 분석을 시도하였으나, 각 집단별 인원이 30명 미만으로 응답 결과의 정규성 검정 및 모수적 방법에 의한 통계 분석이 제한되었다. 그러나 가능한 일표본 t-검정을 중심으로 작품 주제 변경 횟수와 조원간 만족도, 작품 지도에 관련된 응답 항목에서 5점 척도 기준 집단간 평균 0.8점 이상 차이가 남을 확인하였고, 이에 대한 대처 방안을 제시하였다.

• 한국환경보건학회지
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• 제17권2호
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• pp.48-53
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• 1991

This study was carried out to investigate age, noise intensity, work period, hearing loss at frequencies, hypertension and to examine correlation of the total quantity of noise exposure(Dose) and blood pressure (Response) in the auto industry during May 1987-December 1987. To perform this study 65 workers were tested. Results of this study were as follows: 1. In frequency analysis, the CS-dip phenomenon occurred around 4000 Hz. 2. Between under of ten years group and over of ten years group, average hearing loss value was statitically significant (P < 0.05). 3. The prevalence of hypertension of 65 workers was 7.84% . 4. At 90dB(A) over and 10 years under and workers in the 20's group, the total quantity of noise exposure (Dose) and systolic blood pressure (Response) were statistically significant (P < 0.05). 5. At under 10 years of work period group, the total quantity of noise exposure(Dose) and diastolic blood pressure (Response) were statistically significant(r =0.234, P < 0.1).

• Steel and Composite Structures
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• 제27권6호
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• pp.761-775
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• 2018

In the present work, the recently developed non-polynomial shear deformation theories are assessed for thermo-mechanical response characteristics of laminated composite plates. The applicability and accuracy of these theories for static, buckling and free vibration responses were ascertained in the recent past by several authors. However, the assessment of these theories for thermo-mechanical analysis of the laminated composite structures is still to be ascertained. The response characteristics are investigated in linear and non-linear thermal gradient and also in the presence and absence of mechanical transverse loads. The laminated composite plates are modelled using recently developed six shear deformation theories involving different shear strain functions. The principle of virtual work is used to develop the governing system of equations. The Navier type closed form solution is adopted to yield the exact solution of the developed equation for simply supported cross ply laminated plates. The thermo-mechanical response characteristics due to these six different theories are obtained and compared with the existing results.

• 대한토목학회논문집
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• 제13권5호
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• pp.53-65
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• 1993

본 연구에서는 강성기초의 동적응답을 얻기 위해서 비완화 경계조건(non-relaxed boundary condition)을 적용한 3차원 경계요소를 사용하였다. 경계요소는 장래의 비선형문제의 확장을 위해서 시간영역에서 형식화되었으며 기본해는 무한영역의 Stokes 해를 사용하였다. 본 연구는 검증되었으며 지반기초 및 임의 형상의 지하구조물외 동적응답을 얻는데 이용할 수 있다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.421-428
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• 2004

Acoustic response control of a corner-pinned plate using piezoelectric wafers was studied, both theoretically and experimentally. Three different sizes of aluminum alloy plates were used and available ball joints were employed to hold the plate at the four corners. The plate with the largest aspect ratio showed the largest and most clear responses to the acoustic excitation in the range of frequencies (0～200Hz), and sound pressure levels (80～100dB) as predicted. The reduction of the acoustic response of the plate by piezoelectric actuator was very significant, more than expected, but abatement of the sound transmission through the plate was only slightly altered by the piezoelectric actuator. This work is an original work extending earlier work with doors excited by acoustic fields. The important difference is the used of ball joints to simulate the joints.

• 한국안전학회지
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• 제15권1호
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• pp.167-175
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• 2000

Work performance and human error are complicated phenomena so that it is very difficult to grasp the true nature of them. However, Event Related Potential (ERP) may give a clue to them because human brain reflects diverse psychophysiological process. In the present study, the possibility of ERP application to the ergonomic area was evaluated in view of grasping error symptoms. For that purpose, the subjects were asked to count specific characters in a random character matrix on a computer monitor, and their ERP was compared with their performance data. Based upon the results, the amplitude of P300 was not so high as that in the case of the Odd Ball tasks, correct response corresponded with stable ERP with high P300 amplitude whereas wrong response did with unstable, fluctuating ERP with low P300 amplitude. Those results coincided with the work performance, and it was concluded that 3-wave fluorescent with illumination level of 800 lux would be recommendable for the counting task in concern. Conclusively, ERP including P300 might supply an objective clue to the problem of human errors in cognitive process.

• Asia pacific journal of information systems
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• 제33권3호
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• pp.603-623
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• 2023

While prior work has conducted individuals' password security behavior, there is a relatively neglect to examine individuals' affect and feelings of password fatigue in password change context. Therefore, this study explicated individuals' affective response to the feelings of password fatigue by drawing on several theoretical lens. Survey data collected from 267 users were used to test the model using partial least square analysis. This study found that feelings of password fatigue positively affected the negative password fatigue-induced affect, and also both the feelings of password fatigue and the negative password fatigue-induced affect were negatively related to attitude toward changing passwords, which in turn, leads to the intention to change passwords. Furthermore, this study found that shadow work recognition negatively moderated the relationship between attitude and behavioral intention. This study could offer a new theoretical perspective to understand an individual's security behavior and provide empirical evidences for practitioners in charge of IT security in organizations.

• Journal of Korean Biological Nursing Science
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• 제24권1호
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• pp.67-76
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• 2022

Purpose: The purpose of this study was to find stress mediation strategies for pandemic task forces in the future by identifying role stress experienced by local officials in public health centers working as COVID-19 response task force. Whether they suffered from trauma and post-traumatic stress disorder (PTSD) due to COVID-19 was also determined. Methods: Subjects for this research were 185 public health center workers in 7 northern Gyeonggi cities with at least three months of COVID-19 response task force experience. The investigation lasted for two months, from February to March of 2021. Data were collected using a self-administered questionnaire. Results: The average role stress of research subjects was 2.79±0.60. There were 64 subjects (34.6%) who answered 'yes' for trauma experience due to COVID-19. Subjects' role stress by sociodemographic and role characteristics displayed statistically significant differences in gender (t = -2.74, p= .007), age (F = 6.41, p= .002), profession (F = 0.01, p= .014), and COVID-19 response task (F= 3.01, p= .019). Specifically, role stress was higher for females than for males, those who were in their 20's (than 40's), a nursing profession (rather than others). Role stress was also higher in COVID-19 confirmed response work or in a self-quarantine work. There was a significant difference in trauma according to COVID-19 response roles (χ² = 26.59, p= < .001) and other tasks given or not (χ²= 9.48, p= .002). Conclusion: It is necessary to take measures to reduce COVID-19 response task force's role stress and trauma.

• 한국직업건강간호학회지
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• 제8권1호
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• pp.56-67
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• 1999

This study was designed to identify the relationships of role-conflict and role-overload, coping strategies, and stress response of clerical workers. The subjects were 115 clerical workers from two company. The instruments were the role-conflict and role-overload scale developed by Lee(1989), coping scale developed by Latack(1986), and the stress response scale developed by Chang(1993). Analysis of data was done by descriptive statistics, Cronbach's $\alpha$, Pearson correlation coefficietnt, ANOVA. The results of this study were summarized as follows ; 1. The average score for the level of stress response was $83.6({\pm}9.1)$. The high risk stress group was 86.1% of the clerical workers, the latent stress group members was 13.9%, and healthy group was 0%. The overall stress level was very high. 2. Considering the coping strategies by sociodemographic factors, the use of control coping strategies showed significant differences by work-time. The use of symptom management coping strategies showed significant differences by sex, age, married status, year of career, pay, and type of work. The organizational coping strategies showed significant differences by year of education and type of work. 3. The clerical workers who had worked below 44 hours per week complained significantly lower stress response(F=4.942, p<.05). 4. Above 65% of all respondents answered that they needed all of organizational level coping strategies. 5. The role-confilct positively related to escape and organizational level coping strategies(r=.562, r=.495, p<.05). The role-overload didn't related to individual level coping strategies, but positively related to organizational level coping strategies(r=.320, p<.05). 6. The control coping strategies and the escape coping strategies positively related to symptom management, organizational level coping strategies(r=.409, r=.324, r=.316, r=.339, p<.05). 7. The relationship between role-related stress and stress response revealed positive correlation(r=.482, r=.431, p<.05), and the relationship between stress response and control, symptom management coping strategies revealed negative cor-relation(r=-.3204, r=-.3146, p<.05). In conclusion, this study revealed that relationship of role related stress, coping strategies, stress response was statistically significant. The result of this study support that coping strategies vary across situation of stress. Based on survey results, future studies should consider coping strategies in specific stress situation and concept of symptom management coping strategy. Also organizational or training interventions could be developed and initiate to help to increase the use of adaptive coping strategies in light of individual and situational differences.