• 대한가정학회지
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• 제32권1호
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• pp.31-46
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• 1994

the purpose of this study is to investigate (1) the real life of urban employed husbands and their wives(2) the balance between labor force reproduction and the labor force consumption(3) and the share of family responsibility by analysis patterns of their time use. Data for 227 couples were gatherd from using structured questionnaire and time diary. (1) Because of Husbands' long labor time and employed wives' roleoverload their social-cultural time is too short which means the pattern of their time use are very unbalanced type. (2) Regardless of wives' employment status husbands' housework time is too short which means that family responsibility is scarcely shared.

• The Journal of Korean Physical Therapy
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• 제32권4호
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• pp.198-202
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• 2020

Purpose: This study examined the effects of a paraffin treatment with exercise on the muscle strength and fatigue of the hand according to the use of smartphones. Methods: The measurement subjects were 30 healthy males in their 20s who were divided randomly into the control and paraffin treatment groups. A typing exercise using a smartphone was performed. The pinch grip force was measured to evaluate the muscle strength of the thumb, and muscle fatigue analysis using electromyography was performed to analyze muscle fatigue. Results: The functional changes to the arm and the fatigue of the hand through the use of a smartphone were examined to determine the effects of the paraffin treatment. The dominant hand-pinch grip force test did not show a significant difference, but the non-dominant hand-pinch grip force test showed a significant difference between the groups (p=0.030). In the dominant hand fatigue test, there was a significant difference between the groups (p=0.037). In the non-dominant hand, there was a significant difference between time (p=0.012) and the groups (p<0.001). Conclusion: The effects of paraffin intervention on the hand muscle strength and fatigue due to repeated use of the smartphone were confirmed. These results can be used as a basis for clinical use and can be a guide for the correct use of smartphones, which are essential in modern life.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.674-678
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• 2003

This research is develop the sensing and measurement technology for measure that wheel/rail interaction force to use laser. Investigated existent laser measurement system, and examined transformation by load that action to wheel for achieve research purpose. A proposed to laser measurement system composition plan to analyze existent method that measure wheel/rail interaction force.

• 수산경영론집
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• 제43권1호
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• pp.49-61
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• 2012

The tax exemption oil for fishery is expecting that the use of oil is gradually decreasing according to the environmental change such as reductions of vessel force caused by an upswing of oil prices and reduction of fishing vessels in the recent. Such reductions in the tax exemption oil amount have a negative effect on the tax exemption oil business and the fishery infrastructure. This paper studied to provide the basic data for a stable supply thorough the facts affected in the use of the tax exemption oil and the prediction for the use of the tax exemption oil in future. This analysis drew a estimation method by Cochrane-Orcutt repeated proceeding model with an object main factors such as a price of tax exemption oil and vessel force and international oil prices and exchange rates. And this analysis also drew the use of a tax exemption oil by 2000 after set up the scenario using an estimation method drawn. For the use of the estimated tax exemption oil analyzed to decrease within about 81 percent of the present(2020), It should be considering a stability plan for tax exemption oil for fishery in future.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.135-139
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• 1992

Control of tool-environment interaction force to comply the robot system to an environment is of vital in many automated process. This paper presents the implementation of an adaptive force control with commercial robot system in two dimensional contour following task. A model reference adaptive control system, combined with the linear compensators, is implemented. That is, a use of adaptive control is to provide an auxiliary control system so that the contour following performance can be improved from that of using linear control system only. Hyperstability is used to derive the adaptive control law. Experimental verification of the proposed control system is obtained using PUMA 560 robot system. Data obtained experimentally shows that the use of additional adaptive control system improves the contour following performance about 30% in RMS contact force errors upon that of the system controlled by the linear compensators only.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.553-556
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• 2002

A numerical study on the use of the momentum interpolation mettled for flows with a large body force is presented. The inherent problems of the momentum interpolation method are discussed first. Numerical experiments are performed for a typical flow involving a large body force. The tact that the momentum interpolation method may result in physically unrealistic solutions is demonstrated. Numerical experiments changing the numerical grid have shown that a simple way of removing the physically unrealistic solution is a proper grid refinement where there is a large pressure gradient. An effective way of specifying the pressure and pressure correction at the boundary by a local mass conservation near the boundary is proposed, and it is shown that this method can effectively remove the inherent problem of the specification of pressure and pressure correction at the boundary when one uses the momentum interpolation method.

• 제어로봇시스템학회논문지
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• 제16권9호
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• pp.876-882
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• 2010

Stroke patients can't use their hands because of the paralysis their fingers. Their fingers are recovered by rehabilitating training, and the rehabilitating extent can be judged by measuring the pressing force to be contacted with two fingers (thumb and first finger, thumb and middle finger, thumb and ring finger, thumb and little finger). But, at present, the grasping finger force of two-finger can't be accurately measured, because there is not a proper finger-force measuring system. Therefore, doctors can't correctly judge the rehabilitating extent. So, the finger-force measuring system which can measure the grasping force of two-finger must be developed. In this paper, the finger-force measuring system with a three-axis force sensor which can measure the pressing force was developed. The three-axis force sensor was designed and fabricated, and the force measuring device was designed and manufactured using DSP (Digital Signal Processing). Also, the grasping force test of men was performed using the developed finger-force measuring system, it was confirmed that the grasping forces of men were different according to grasping methods.

• 한국안전학회지
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• 제28권4호
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• pp.103-106
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• 2013

During a military service, noise has unusual characteristics, and constitutes a serious hazard to hearing of military servicemen. The purpose of this study is to understand the use of hearing protection and to assess the safety effects of hearing protection by using a ear plug in military. A total of 208(the army : 101, an air force : 107) serviceman were studied utilizing a questionnaire to know how many serviceman use the hearing protection and a total of 202(the army : 110, an air force : 92) serviceman were also studied using a ear fit validation device to assess the safety effects of hearing protection by using a ear plug. The results showed that the army have low used of hearing protection than an air force because of the low frequency of the noise exposure in the army. Personal attenuation rate was increased with 8 dB after fitting education. Therefore, it is recommended that use of proper hearing protection and fitting education was more suitable for military servicemen who were being exposed of the noise in domestic military.

• 대한치과교정학회지
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• 제20권2호
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• pp.409-417
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• 1990

Tooth movement would be impeded by frictional force arised between archwire and tube, bracket or elastics in the fixed orthodontic appliances, which could be changed variably by such several factors as the contact area, normal (perpendicular) force and the condition of contact surface. There were many literatures about frictional force in the orthodontic region, but different results were obtained from little controlled research so that was very difficult in clinical application. Therefore we have reviewed comprehensively previous literatures about frictional force and thus several results were obtained as follows: 1. For use species of the orthodontic wire, frictional force was influenced mainly by surface roughness of wire in the absence of binding, while that was influenced mainly by normal force in high binding angulation. 2. For the cross-section and diameter of the wire, the contact area influenced mainly on frictional force in the absence of binding, while wire stiffness influenced mainly on frictional force in high binding angulation. 3. The greater the bracket width, the greater frictional force, and frictional force of the plastic bracket was larger than that of the metal bracket. 4. For ligation type, frictional force of the stainless steel ligation was larger than that of the elastic ligation, and frictional force was directly proportional to ligation force. 5. Variable frictional force were occured from the saliva combined with such another factors as normal force and mode of surface oxide et al.

• 한국정밀공학회지
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• 제15권11호
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• pp.9-20
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• 1998

In recent manufacturing process, the increase of productivity has been attempted by reducing machining time with the increase of cutting force. However, the excessive increase of cutting force can cause tool breakage and have a bad effect on both manufacturing machine and workpiece. Thus, it is necessary to estimate and control the cutting force in real time during the process. In this study, use of disturbance observer is proposed for the indirect cutting force estimation. The estimated cutting force is used for the real-time control of feedrate, making the actual cutting force follow the reference force command. Since the suggested method does not need an expensive sensor like a dynamometer, the method is expected to be used practically. Since the actual cutting force follow the reference force, resulting the reducing of the machining time the increase of productivity are also expected, and the quality of cutting surface has been improved due to the adjusted feedrate. Besides, an actual constant cutting force guarantees the prevention of tool breakage. To show the effectiveness of the suggested cutting force control method, an experimental setup has been made without sensor and applied to several workpieces. Experiments show that the suggested method is effective to cutting force control of a CNC machining center.