• Journal of the Korea Society for Simulation
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• v.15 no.3
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• pp.39-47
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• 2006

In most of supply chain planning practices, the estimated demands, which are forecasted for each individual period in a forecasting window, are regarded as deterministic. But, in reality, the forecasted demands for the periods of a given horizon are stochastically distributed. Instead of using a safety stock, this study considers a direct control of service level by choosing the demand used in planning from the distributed forecasted demand values for the corresponding period. Using the demand quantile and echelon stock concept, we propose a simple but efficient heuristic algorithm for multi-echelon serial systems under service level constraints. Through a comprehensive simulation study, the proposed algorithm was shown to be very accurate compared with the optimal solutions.

• 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.145.1-145
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• 2003

신선편이 최소가공 근채류의 초기 품질 유지 및 유통기간의 연장을 위한 기초연구로 박피처리 조건별에 따른 품질특성을 조사하였다. 감자의 경우 sandpaper를 이용한 구근류 박피기로 박피된 감자의 감모율이 8%이하로 가장 낮게 나타났으며, 화학적 방법에 의한 박피가 8.9~9.8% 수준으로 NaOH의 농도가 높아질수록 감모율이 높아 17% NaOH용액으로 처리한 박피 감자의 감모율이 가장 높게 나타났다. 박피후의 수분함량 변화는 수작업과 15% NaOH 8$0^{\circ}C$에서 2분간 침지 후 박피된 처리구에서 박피 3시간 후 급격하게 감소되었다. pH는 화학적 박피 처리구는 5.78~6.33으로 수작업 박피의 6.53~6.81과 기계적 박피 처리구의 5.89~6.61에 비해 비교적 낮게 나타났다. 갈변도는 8$0^{\circ}C$, 15%-NaOH에 2분간 침지 후 박피된 처리구는 0.87로서 수작업 박피 직후의 갈변도 0.19에 비해 무려 4.5배 가량 높게 나타났다. 한편, 박피처리한 고구마는 감자에 비하여 갈변이 적게 일어났으며 감모율도 비교적 낮아 sandpaper를 이용한 구근류 박피기로 처리된 고구마가 7.3% 수준으로 가장 낮은 감모율을 나타내었고 10$0^{\circ}C$, 10%-NaOH에서 1분간 침지하여 박피한 처리구가 13.6%로 가장 높은 감모율을 보였다. pH는 시간 경과에 따라 6.51~5.94 수준으로 낮아지는 경향을 보였으며, 갈변도는 박피도구를 이용한 수작업에 있어 박피 3시간 경과 후에도 0.98 수준으로 가장 낮게 나타났다.

• Journal of the Korean Society for Railway
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• v.15 no.2
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• pp.193-198
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• 2012

As a result of investment in railway safety since 2004, railway accidents have been reduced by half and we reached a high level of safety compared to other countries. But people are still worries about railway accident, and want safer railway. It is difficult to determine which level of safety must be achieved due to lack of comparative studies on railway safety among different countries and other transportation modes. In this study, a comparative study on railway accident statistics and various transportation modes is performed. The results of this research can be used for the determination of weak areas of railway safety and the level of safety to be achieved.

• 모자간호학회지
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• v.4 no.1
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• pp.24-32
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• 1994

Using data from the Korean National Health Survey conducted in the years 1989 and 1992, child and maternal ambulatory care utilization patterns were compared. Data from 3,002 families from the 1989 survey and 1,523 families from the 1992 survey which have a child 0-4 years old and mother in the same family were selected and used for the analysis. The results indicate that child medical utilization is closely accociated with maternal medical utilization, as measured by the number of visits to medical facilities. Maternal use appears to be a more powerful predictor of child use than any other family and maternal variables. These results confirm the result of the previous localized studies and suggest that intervention directed at the mother may be effective in ensuring equitable and efficient use of ambulatory services by childeren.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.451-456
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• 2020

This study compared the utility of walking aids, and activities of daily life depending on the ability of people with mobility disabilities to use walking aids. Data were extracted from the Korea Welfare Panel Study in 2014. Data of 435,947 individuals were analyzed using chi-square and t-tests. The findings from this study showed that disabled persons who cannot use walking aids independently were more likely to have a severe disability level and a lower level of daily activities than the independent group. The level of social participation and leisure activities were also significantly lower in the dependent than the independent group. Therefore, walking aids should be tailored for individuals depending on their level of independence for using walking aids.

• Journal of the Korean earth science society
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• v.28 no.3
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• pp.259-265
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• 2007

The purpose of this study was to examine the effects of the application time of differentiated instruction in terms of learners' science academic knowledge achievement and their attitudes toward science. The findings of the study were as follows: First, the experimental group was significantly higher than the control group (p<.05). Second, the academic knowledge achievement of high ability students of two subgroups was not different (p>.05), but the achievement of low ability students was higher in experimental group than in control group (p<.05). Third, the experimental group showed higher improvement in attitude toward science than the control group in three areas of the Test of Science Related Attitudes (TOSRA) (p<.05): 'Adaptation of Scientific Attitudes', 'Enjoyment of Science Lessons', and 'Career Interest in Science'. However, there was no significant difference between the experimental and control groups in the area of 'Attitude to Scientific Inquiry' and 'Leisure Interest in Science'.

• Journal of Technology Innovation
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• v.21 no.1
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• pp.85-108
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• 2013

This paper introduces a new qualitative measurement indicator, Relatively Rank-normalized Impact Factor ($R^2nIF$) that can overcome drawbacks of the existing research performance measures. With the help of this innovative indicator, this study analyzes and compares the quality of research papers across countries and National Science Indicators (NSI) standard academic fields. The development of an improved bibliometric indicator for evaluating the quality of research papers and disentangling the "international" dimension of research performance will be of interest to academics and practitioners alike.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.123-129
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• 2017

This study investigated the dental prosthesis condition from the sixth primitive data of Korea National Health and Nutrition Examination Survey to analyze and compare the necessity of existent dental prosthesis condition, dental bridge and dentures in order to determine the real oral health condition by educational level targeting adults aged over 20 years old. From the results, based on demographic-sociologic features, 32.2% of females were under elementary school graduation level, which was lower than males, and the educational level decreased with increasing age, and these trends were statistically significant. As for income level, 45.3% of university graduates had the highest income level and 77.4% of this age group were professionals, which was the highest percentage and was statistically significant. In terms of dental prosthesis condition according to educational level, the under elementary school graduation group had the most dental prosthesis and the greatest need for partial dentures and full dentures. As for the necessary number of fixed implants, the upper jaw had the most number of fixed implants and in the lower jaw, the under middle school graduation needed the most fixed implants.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.255-258
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• 2003

합섬소재를 이용한 의류용 직물설계1)에 있어 원료의 특성과 경ㆍ위사의 번수, 직물의 조직 및 밀도에 따른 직물설계 조건$^{2)}$ 은 다양하게 변할 수 있다. 그럼에도 불구하고 현장에서 적용할 수 있는 이론적 배경과 실제 현장에서 적용할 수 있는 데이터는 미흡한 수준이다. 따라서 다품종 소량 생산 체제에 대비하는 다양한 소재의 설계에 필요한 Data Base 구축이 필요한 실정$^{3)}$ 이다. 본 연구는 직물용 CAD System에서의 합섬 의류용 직물설계에 응용 가능한 DB를 구축하기 위해 국내 직물설계$^{4)}$ 와 일본 직물설계$^{5}$)를 비교하여 국내직물의 수준을 향상시킬 목적으로 실제 현장에서 사용되고 있는 각각 100여 종류의 직물설계조건들을 조사ㆍ분석하여 국내와 일본 직물설계를 비교함으로써 감성 의류용 합섬 소재 설계에 있어 체계적인 지표가 되고 보다 우수한 품질을 위한 직물설계의 기초자료를 제공함으로써 현업에 있는 업체와 기관에 도움을 주고자 한다. (중략)

• Journal of Educational Research in Mathematics
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• v.13 no.1
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• pp.1-12
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• 2003

이 논문은 수학적 개념의 뜻과 과 중요성을 살펴본 다음, 연구자가 소속되어 있는 한국의 대학생과 연구자가 연구년 동안 강의한 바 있는 미국의 대학생이 갖고 있는 수학적 개념의 수준에 대하여 조사하여 보고, 그 차이점을 비교하여 수학교육의 개선을 위한 시사점을 찾아보고자 하였다. 본 연구는 수학적 개념을 수학적 지식의 구성, 수학적 지식의 구조, 수학적 지식의 현상, 수학을 행하기, 수학적 아이디어의 가치 인식, 구성으로서의 학습, 유용한 노력으로서의 수학으로 분류하고 각 개념에 대한 양국 학생들의 인식 정도를 설문조사 방식으로 조사하였다. 본 연구에서 한국 학생들은 수학적 개념에 대한 7개의 영역 중에서 '수학적 지시의 현상', '수학을 행하기'를 제외한 5개의 영역에서 더 높은 수준을 보였다. 앞으로 한국의 수학교육은 수학을 실제로 행하는 활동을 더욱 강조하여야 할 것이다.