• Korean Journal of Computational Design and Engineering
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• v.6 no.4
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• pp.215-221
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• 2001

In the zigzag milling of a pocket having islands, tool retraction is one of the primary factors that decrease productivity. Therefore, tool path with minimum number of tool retraction has been needed. Most researches about this topic have been concentrated on obtaining the optimum solution formulated through the geometric reasoning off pocket. Recently, several attempts were made to simplify this problem into region partitioning in order to get the numerically expressed minimum solution. In this research, a method reducing the number of tool retractions extended from existing region partitioning is provided. Applying the segment that is normal to the reference direction of zigzag milling, region partitioning is carried out and structural elements of the region are searched via graphs of islands and characteristic points. Through the processes presented, the number of region partitioned is less than that of existing processes.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.220-228
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• 1999

The machining accuracy has been improved with the development of NC machine tools and cutting tools. However, it is difficult to obtain a high degree of accuracy when machining deep pocket with long end mill, since machining accuracy is mainly dependant on the stiffness of the cutting tool. To improve surface accuracy in machining deep pocket using end mill, the performance by down cut and up cut is compared theoretically and experimentally. To verify usefulness of up milling, various experiments were carried out. As a result, it is found that up milling produce more accurate surface than down milling in machining deep pocket. For effective application of up milling, various values in helix angle, number of teeth, radial depth of cut and axial depth of cut are applied in experiment.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.667-673
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• 2024

This study aims to diagnose the issues arising from the relationship between the out-of-pocket maximum in health insurance and private indemnity health insurance and propose policy tasks for institutional improvement. Through literature research, the study analyzed the damage to consumers caused by the non-payment of refunds exceeding the out-of-pocket maximum and the changing role of indemnity insurance due to the strengthening of health insurance coverage. The results confirmed that unilateral interpretation of insurance clauses and incomplete sales practices infringe upon consumer rights, and that insurance premiums do not decrease despite the reduction in coverage of indemnity insurance. Therefore, the study emphasized the urgency of institutional improvements such as rationalization of product structure, transparency of risk rate calculation, and reinforcement of consumer information provision, as well as the need for social consensus on the rational division of roles between health insurance and private insurance. This study is significant in that it provides policy implications for the developmental reorganization of the healthcare system.

• The Journal of Korean Medicine
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• v.25 no.1
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• pp.142-151
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• 2004

Objectives : To document the use and out-of-pocket expenditure of complementary and alternative medicine(CAM) in Korean adult population. Methods : Nationwide, random-sampled, and population-weighted telephone survey was conducted. The sample size of respondents was 1,000(age over 18). The respondents were asked about their use, out-of pocket expenditure of CAM in the past 12 months. SAS 8.0 statistic package was used for checking the relevance between each variables by performing $x^2-test$ and variance evaluation. Results : In 2001, 64.0% of people experienced more than one alternative therapy and the beneficiary took therapy average figure of 2.07. Alternative therapies were generally used for health promotion(73.7%) rather than curing the disease(26.3%). The most common therapies included Medication(30.2%), Physical-therapy(21.9%) health implements(20.8%), herb medication(19.2%), diet therapy(14.3%) etc. Average annual out-of-pocket expenditure was ￡<192,186. Use varied according to age, living province, income, and education, while cost expenditure did according to sex, health condition, income, education. Conclusions : The use of CAM in Korea is very large and the expenditure for them is 22.6% of national medical expenditure. It shows great need of political and academic approach.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.1 no.1
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• pp.38-47
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• 2002

Machining quality has been improved with the development of cutting tools. However, it is difficult to obtain a high degree of quality in machining a deep pocket with a long end mill, since machining accuracy is mainly dependent on the stiffness of the cutting tool and tool holder. To improve machining quality in machining a deep pocket using an end mill, the performance by cutting condition compare with others. Owing to this problem, it is necessary to select suitable tool and holder in the deep pocket machining. In this study, the hydraulic holder for the high speed machining is introduced and the performance of that is compared with others according to cutting conditions. The cutting parameters involved were; slenderness ratio in the range of 3 to 6 (L/D), radial depth of cut from 0.01 to 0.05 mm. Cutting force and surface roughness, precision of form were observed during the experiment to investigate cutting state.

• Korean Journal of Human Ecology
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• v.7 no.2
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• pp.35-47
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• 1998

The purpose of this study was to examine the actual condition on consumption of adolescents, focused on their pocket money. Three-hundred students attending in middle and high school in Kyounggi Province were selected, and surveyed using questionnaires. Out of them, 272 students were used in statistical analysis, with frequency, percentage and Chi-test in SPSS/PC+ program. The results were as follows : First, most adolescents got pocket money irregularly from their mothers and average amount per month was more than 10 thousands and less than 50 thousands won. And they weren't satisfied with that amount, especially girl students. Second, most adolescents got extra money when it is a gala day or their records were improved. And most of them did nothing on consideration for their pocket money. Third, most adolescents spent pocket money for hobby or leisure and for snacks. Fourth, most adolescents had never guided how to spend money and had never evaluated their money spending. Fifth, most adolescents tried to spend money thoughtfully and evaluated their friends spent money on impulse. Sixth, most adolescents wanted to buy clothings and friends influenced their spending habit.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1989.11a
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• pp.94-99
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• 1989

This paper analyzes file stiffness, damping coefficient, friction force and flow coefficient of externally pressurized oil journal beating, including the effect of journal rotation according to the Sommerfeld number. This paper assumed that the oil in the whole pocket has constant pressure, and that the oil in the whole bearing region has constant viscosity, temperature and density. Reynolds equation is derived from Nuvier - Stokes equation and continuity equation. And solved bearing pressure by ADI method for whole bearing region and fitted with out flow rate of pocket region. The model for numerical simulation is hydro - static oil journal bearing for high-speed, high-accuracy lathe spindle.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.4
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• pp.160-164
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• 2014

Recently, there has been an active study about friction force of moving parts for automotive. This study is development and evaluation of oil pockets for journal bearing and tappet valve for range extended electric vehicle. Specially, oil pockets are effect on friction force depend on pitch, size, depth. In this study, fine oil pocket was formed using by etched texturing on the journal bearing and tappet valve. And oil pocket analyzed by SEM and friction force test was carried out by tensile tester. Finally, in this study, it was suggested by round and plane part which journal besring and tappet valve.

• Computers and Concrete
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• v.20 no.4
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• pp.483-490
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• 2017

This paper studies on the behavior of reinforced concrete (RC) pipes used in basic sanitation in the conduction of storm water and sanitary sewer. Pipes with 800 mm and 1200 mm in diameter were analyzed. The 800 mm pipes were built with simple reinforcement and the 1200 mm pipes with double reinforcement. For the two diameters of pipes the presence or absence of the pocket was evaluated, and the denomination of each one is spigot and pocket pipe (SPP) and ogee joint pipe (OJP), respectively. The 3D numerical models reproduce the three-edge-bearing test that provides information about the strength and stiffness of the reinforced concrete pipes. The validation of the computational models was carried out comparing the vertical and horizontal displacements on the springline and crown/invert and it was also evaluated the reinforcement strains and the crack pattern. As a main conclusion, the numerical models represented satisfactorily the behavior of the pipes and can be used in future studies in parametric analysis.

• The Korean Journal of Rehabilitation Nursing
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• v.12 no.2
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• pp.112-119
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• 2009

Purpose: The purpose of this study was to investigate leisure activities, leisure life satisfaction, perceived health status and depression in the elderly and to examine the relationships among those variables. Method: The subjects were 204 elderly visiting a senior welfare service center in G city. Data were collected from September 14 to 18 in 2009. All subjects agreed to participate and filled out the survey questionnaire after signing the consent form. Results: 1) The mean score of leisure activities was 2.81; the mean score of leisure life satisfaction was 4.14; the mean score of perceived health status was 8.92; the mean score of depression was 5.13 and 42.2% of the subjects belonged to the depression group. 2) The level of leisure activities was significantly different according to education level, religion, spouse and pocket money. The level of leisure life satisfaction was significantly different according to religion and pocket money. The level of perceived health status was significantly different according to sex, education level and pocket money. The level of depression was significantly different according to spouse and pocket money. 3) Leisure activities showed positive correlation with leisure life satisfaction and perceived health status, but showed negative correlation with depression. Conclusion: These findings showed the need for the health promotion program that increases leisure activities and leisure life satisfaction without economic burden.