• Journal of Korean Society for Quality Management
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• v.29 no.2
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• pp.93-103
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• 2001

This study examined the social perceptions on the women work force in Korean service industries. 100 questionnaires per each of five service industries, hotel, PCS, department store, general hospital and bank (500 altogether) were distributed to general consumers to measure perceived service quality and perceptions on the women employees in the those service industries. It was found that consumers were not very satisfied with the service quality of the industries. They felt the necessity of women workforce in service industry and agreed to that women employees posessed management quality and had potential to develop.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.6
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• pp.859-866
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• 2010

Generally, a fixed type guide-bush system is installed during machining miniature work-pieces with high precision in the multi-task CNC lathe. But a conventional guide-bush system does not provide a constant clamping force under the condition of varying work-piece diameters. It is important to maintain a constant clamping force for guaranteeing machining precision. This paper proposes a new guide-bush system with a pneumatic clamping device for the CNC Swiss-turn lathe to keep constant clamping force with changes in work-piece diameters. Through performance tests, new clamping system developed in the study showed better machining precision at the cost of a small increase in the temperature of the system than conventional systems due to an increase in the frictional heat and a change in the heat transfer route.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.7 no.2
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• pp.289-297
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• 1997

Work-related low back pain(below LBP) is one of the major cause of morbidity, disability, limitation of activity and economic loss. Therefore the work-related LBP is one of the major issue in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the effective control programs of work-related LBP. The subjects were male workers employed at the welding and metal factory. The data was collected by self-reported questionnaire, interview and checking abdomen muscular and grasping power for two days on October, 1993. The contents of questionnaire were as follow: the experience of LBP, general characteristics, physical characteristics, employment status, type of work and working environment. The number of cases was 104 with a history of work-related LBP, so the prevalence of work-related LBP was 35.0%, and the number of controls was 140 without any history of LBP. As a result, marital status, educational level, abdomen muscular power, tenure, category of job, satisfaction of job, working posture, satisfaction for table and chair and lifting materials showed a statistical significance between the case and control groups. 284 Lifting jobs were quantified by NIOSH lifting equation method and ergonomic computer modelling methods. There were no significant differences in the action limit and disc compression force between group with LBP and without LBP. But in the lifting frequency and cumulative disc compression force there were significant differences. Therefore work-related LBP should be prevented by the ergonomic and environmental control.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.293-296
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• 2002

This work presents the reconstruction of impact force produced by the collision between two elastic structures. The 2-DOF impactor was designed. The shape control of impact farce using correlations of the dynamic characteristics and impact force history between two elastic structures is accomplished. The effects of the relative motion between impactor and elastic structure on the impact force shape are studied. Reconstruction characteristics of impact force in cantilever beam are reviewed.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.218.3-219
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• 2003

백편을 만들 때 멥쌀가루 100에 찹쌀가루를 총중량의 0%, 5%, 10%, 15%, 20%, 25%, 30% 첨가하고 저장시간 0시간, 24시간, 48시간, 72시간 저장한 후 (4$^{\circ}C$에서) reheating 한 백편의 기호성과 조직감(Texture)에 어떠한 영향을 끼치는 가를 관능검사와 기계적 검사에 의해 측정한 결과를 다음과 같이 요약할 수 있다 1. 관능검사 결과 백편의 Color 는 찹쌀의 첨가량이 증가할수록 누런색이 짙어졌으며, 24, 48, 72 시간 저장한 후 reheating 한 백편도 누런색이 짙어지는 경향을 나타냈다. Coarseness 는 찹쌀의 첨가량이 증가할수록 증가하는 경향이었으나 저장전의 백편은 유의적인 경향을 나타내지 않았다. 찹쌀의 첨가량이 증가할수록 Softness, Dryness, crumblyness는 감소경향을 나타냈으며 24, 48, 72 시간을 저장한 후 reheating 한 백편도 유의적인 감소경향을 나타냈다. 외관의 기호도는 찹쌀의 첨가율이 5% 인 백편을 가장 좋아했고, 조직감 및 종합적인 기호도는 찹쌀의 첨가율이 10~20%인 백편을 좋아했다. 2. Rhemeter에 의한 백편의 Texture는 찹쌀의 첨가량이 증가할수록 Compression force, gumminess, Chewiness가 증가하는 경향을 나타냈다. 24, 48, 72 시간 저장한 후 reheating 한 백편은 저장전보다 점점 감소경향을 나타냈다가 72시간 저장한 후 reheating 하면 다시 증가경향을 나타냈다. Work ratio 및 Recovered height는 찹쌀의 첨가량과 저장시간의 변화에 크게 영향을 미치지 않았다. Recovered 하지 않고 0, 24, 48, 72 시간 저장한 백편의 Compressing force는 찹쌀의 첨가량이 증가할수록 증가경향이 컸고 저장시간이 경과함에 따라 Compression force가 증가하였는데 특히 24시간 저장하는 동안 급격히 증가하였다. 3. 찹쌀 첨가량이 증가할수록 수분함량은 증가하였고, 저장시간이 경과함에 따라 수분함량은 감소경향을 나타냈으나 24시간 저장한 후 reheating 한 백편만이 수분함량의 증가경향을 나타내었다. 4. qoruvs의 Softness 는 Compression force 및 Work ratio 와 유의적인 상관관계를 나타내었으며, Dryness 와 Crumblyness 는 Work ratio와 유의적인 상관관계를 나타내고 있어 백편의 조직감은 Compression force 와 Work ratio로 대치할 수 있을 것이라고 사료된다. 수분함량은 기계적 검사보다 관능검사와 더욱 높은 상관관계를 나타냈다.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.235-235
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• 2000

This paper proposes a tole force feedback control through internet systems. The system consists of joystick, solver, client, robot, and internet. The main contribution of this work is the implementation of the system rather than theoretical analysis. The time delay problems will be considered next step.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.536-542
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• 2002

There are two important variables in machining process control, which are feed and cutting speed. In this work, a two degree-of-freedom controller is designed and implemented to achieve on-line cutting force control and position control based on the modelling of cutting process dynamics which are established through step response test. Two schemes are proposed and implemented. The first is feed control under the constant spindle speed and spindle speed control under the constant feed speed. The second is a simultaneous control of feed and spindle speed. The last performs a position control under the constant cutting force. Those are confirmed to work properly. Especially the latter shows a faster response.

• KSTLE International Journal
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• v.7 no.1
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• pp.10-13
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• 2006

In this work, imaging and study of elastic property of the living cell was performed. The motivation of this work was to seek the possibility of exploiting Young's modulus as a disease indicator using Atomic Force Microscope (AFM) and also to gain fundamental understanding of cell mechanics for applications in medical nanorobots of the future. L-929 fibroblast adherent cell was used as the sample. Imaging condition in cell culturing media environment was done in very low speed ($20{\mu}m/ s$) compared to that in the ambient environment. For measuring the Young's modulus of the living cell, AFM indentation method was used. From the force-distance curve obtained from the indentation experiment the Young's modulus could be derived using the Hertz model. The Young's modulus of living L-929 fibroblast cell was $1.29{\pm}0.2$ kPa.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.1
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• pp.147-152
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• 1993

The lapping characteristics of single crystal diamond are studied by considering the crystallographic anisotropy. It is introduced for lapping method to identify crystallographic orientantion by the X-ray diffraction and to measure lapping force ratio, lapping temperature and lapping wear. Diamound bonded wheels are used for lapping under dry condition. On the lapping {110} and {100} planes, it shows remarkable crystallographic anistropy. The lapping force ratio, temperature and wear become gerater with sliding direction along the <100> than along <110>. The results also show that the wear of diamond is influenced by mechanical work(tangential lapping force * lapping distance) as well by lapping speed.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.116.3-116
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• 2002

Introduction $\textbullet$Teleoperation System for Wiping Operation $\textbullet$Virtual Force Generation Algorithm $\textbullet$Virtual Velocity Generation Algorithm $\textbullet$Force-Force Control Technique $\textbullet$Experimental Results and Discussion $\textbullet$Conclusions