• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.1
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• pp.27-30
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• 2003

Amethyst is a precious stone in Korea. As natural quartz are usually mixed with smoky quartz, amethyst, and milky quartz, we need to evaluate the amount of the amethyst quantitatively in ores. Although the optical evaluation with bare eyes has been common in assay so far, we propose that the diamagnetic property and microstructural difference characterization be the solution for the evaluating the quartz ores. In addition, FTIR (Fourier transformation infra-red) could help to identify the amethyst transparency. We report that we could evaluate the amethyst quantitatively with M-H hysteresis characterization, transmission electron microscopy (TEM) observation and FTIR characterization.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.429-438
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• 2019

This study was to evaluate the level of traffic safety related to domestic traffic accidents by analyzing the international comparison of road traffic accident indicators and to set goals and directions of traffic accidents in Korea in the future. The research procedure was as follows: First, population, number of registered vehicles, roadway length, vehicle kilometers, injury accidents, fatalities, injuries were collected in 32 OECD countries. Second, we determined Korea's traffic safety rankings through international comparison of traffic accident rate. Finally, we analyzed the level of traffic safety by comparing Korea with the 7 advanced countries with the traffic accident rate per vehicle kilometers. The accident rate in Korea was greater than two times higher than those of the seven major developed countries, which showed that the level of traffic safety in Korea implied very low. Target values for domestic accidents were proposed based on the accident rate.

• Journal of the Korean Society for Railway
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• v.6 no.4
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• pp.11-18
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• 2003

우리는 복잡한 현상을 하나의 수치로 표현하는 각종 지표(index)를 생활에서 많이 접하고 있다. 종합주가 지수, 불쾌지수, 소비자 물가지수, 년간 교통사고 건수, 인구 10만명당 교통사고 사망자수 등도 일종의 지표라 할 수 있다. 철도에서도 위험을 평가하는 지표로는 "년간 사고건수", "열차운행 100만-km당 사고건수"와 같이 발생빈도에 초점을 둔 경우와 "년간 사망자수", 혹은 "피해액", "운행지장"과 같이 사고피해에 초점을 둔 경우가 있다. (중략)

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.16-25
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• 2013

This study deals with the relationships between flashing operation and traffic accident at signalized intersections. The objective of this study is to analyze safety effects of the yellow flashing operation at night. In pursuing the above, this study gives particular attention to evaluating the safety results from signal operation of Cheongju's 190 signalized intersections using before-after evaluation with comparison group that are categorized by highway function. The main results are as follow. First, the numbers of traffic accidents and of fatalities/injuries in two highway types (arterial and collector road) have increased after operating the yellow flashing signal at night. Second, the numbers of accidents, fatalities/injuries, severe accidents and of fatalities/severe injuries in group A(arterial) have increased by 19%, 36%, 15% and 14%, respectively. Finally, the numbers of accidents, fatalities/injuries, severe accidents and fatalities/severe injuries in group B (collector) have increased by 50%, 64%, 41% and 77%, respectively.

• Journal of Korean Society of Transportation
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• v.18 no.4
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• pp.41-50
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• 2000

신호교차로에서 맨 우측차로의 대부분이 우회전 공용차로로 사용되는데 도로용량편람에서 우회전이 불가능한 보행자 횡단시간 비율$(f_c)$은 공용차로의 용량을 결정하는 우회전보정계수$(f_{RT})$의 산정시 중요한 요소가 된다. 그러나 이에 대한 국내의 연구는 미미하여 연구의 필요성이 있다고 생각된다. 본 연구는 유입부의 직진신호시간을 위주로 교차방향 횡단보도 내의 보행자수와 우회전차량의 통과여부를 촬영하여 분석하는 방법으로 진행되었으며, 우회전 차량이 교차도로의 보행자 횡단시간에 보행자와의 상충으로 우회전하지 못하는 시간 비율을 산정함에 있어서 횡단보도의 보행자수에 따라 우회전 차량의 통과율을 구하고 이로부터 횡단보도 보행신호시간동안에 우회전이 불가능한 시간비율을 산정했다. 연구결과는 우회전이 불가능한 시간비율이 시간당 보행자수(양방향)가 500인/시~1,500인/시로 변할 때 0.78에서 0.94사이의 값을 가지며 한국도로용량편람에서 제시한 값 0.3에서 0.9보다는 대체로 큰 것으로 나타났다. 따라서 한국용량편람에서 얻은 우회전차로의 용량은 과대 평가되는 경향이 있다.

• Journal of Animal Science and Technology
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• v.44 no.4
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• pp.377-382
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• 2002

This study was carried out for the simultaneous genetic evaluation of swine breeds from the seedstock farms in Korea. The performance tested production records of 96,842 heads and the litter records of 90,396 litters from 1995 to 2001 were analyzed to estimate the breeding values and the breed effects of days to 90kg, daily gain, back fat thickness, loin muscle area, lean meat percent, total litter size and number born alive from Landrace, Yorkshire and Duroc. Estimated breed effects of traits had shown the characteristics of the breeds. Landrace was superior in back fat thickness and lean meat percent to other breeds. Yorkshire had shown good performance in lean meat percent, loin muscle area, total litter size and number born alive. Duroc was superior to the other breeds in days to 90kg and daily gain. Conclusively, the multi-breed genetic evaluation would result in higher connectedness and provide convenience for the routine genetic evaluation process of swine performance and reproduction test.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.602-605
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• 2003

통신업계의 사업자간 성과를 평가할 때 흔히 사용되는 지표가 ARPU(Average revenue per user) 이다. ARPU란 가입자당 수익으로 사업자의 총 수익을 가입자 수로 나누어 산출된다. 그러나 최근 통신 선진국 등지에서 ARPU적용의 문제점들을 제시하면서 새로운 지표인 AMPU(Average margin per user)를 사용하자는 주장이 일고 있다. AMPU란 가입자당 이익으로 사업자의 순이익을 가입자 수로 나누어 산출된 수치를 말한다. ARPU는 그 산정 메카니즘 상 변수인 수익과 가입자수에 대한 통일된 개념정립이 없으므로 사업자마다 각기 다른 회계처리를 할 수 있다. 특히 수익의 경우는 단말기 매출의 포함여부와 CP들에게 지불될 제3자수익에 대한 처리에 따라 수익수준이 달라지게 되며, 가입자수의 경우 가입자에 대한 정의가 명확하지 않기 때문에 실제 서비스를 이용하고 있지 않은 inactive가입자들의 포함여부에 따라 ARPU수치에 영향을 주게 된다. 따라서 사업자간 일률적이지 않은 회계처리에 따른 ARPU수치를 비교하는 것은 의미 없는 일이 될 수 있고 궁극적으로 이해 관계자들의 의사결정을 왜곡시킬 수 있는 요인이 된다. 따라서 수익과 비용을 모두 고려하는 개념인 AMPU의 사용은 ARPU로 인한 문제점을 해소시킬 수 있을 것이다. 따라서 보다 정확하고 비교가능한 정보를 제공하기 위해서는 통신산업의 사업자들과 이해관계자들이 AMPU지표의 공시에 협조해야 하며, 근본적으로 공시되는 수익이나 가입자수에 대한 개념의 정립이 시급할 것이다.

• The Korean Journal of Applied Statistics
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• v.23 no.5
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• pp.891-908
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• 2010

In Korea, the small area estimation method is currently unpopular in generating o cial statistics. Because it may be difficult to determine the reliability for small area estimation, although small area estimation ha a sufficiently good advantage to generate small area statistics for Korea. This paper inspects the method of making small area unemployment through the small area estimation method. To estimate small area unemployment we used an EBLUP-type estimator based on a logistic linear mixed model. To evaluate the EBLUP-type estimator we accomplished the real data analysis and simulation experiment from the population and housing census data. In addition, small area estimates are compared to large sample survey estimates. We found the provided method in this paper is highly recommendable to generate small area unemployment as the official statistics.

• 종축개량
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• v.17 no.2
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• pp.57-60
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• 1995

카나다의 돼지개량에 대한 국가적 유전능력 평가는 산육능력(100kg의 등지방과 일령)과 모돈의 번식능력(총산자수)을 BLUP animal model(최선형 불변예상치 가축모형 : Best Linear Unbiased Predictor Animal Model)을 이용하여 정규적으로 평가하고 있다. 새로운 검정자료가 수집되어 질때마다 매번 BLUP평가가 이루어져 농장으로 제공된다. 현재의 유전능력 변화에 대한 추정가는 연간 등지방 두께 0.35mm와 100kg도달일령 1.5일이 향상되었다. 이것은 1985년 BLUP이 소개된 이전보다 등지방 $50\%$, 일령 20배 이상의 개량효과이다. 그 외에 모돈의 번식형질에 대한 개량은 계속적으로 연구가 진행되고 있으며 국가적 육종계획에는 도체와 육질에 대한 유전적 개량사업이 추진되고 있다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.4
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• pp.327-339
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• 2022

The purpose of this study is to present the effective smoke control flow rate and mode for securing safety through quantitative risk assessment according to the smoke control flow rate and mode (supply or exhaust) of the platform when a train fire occurs at the subway platform. To this end, a fire outbreak scenario was created using a side platform with a central staircase as a model and fire analysis was performed for each scenario to compare and analyze fire propagation characteristics and ASET, evacuation analysis was performed to predict the number of deaths. In addition, a fire accident rate (F)/number of deaths (N) diagram (F/N diagram) was prepared for each scenario to compare and evaluate the risk according to the smoke control flow rate and mode. In the ASET analysis of harmful factors, carbon monoxide, temperature, and visible distance determined by performance-oriented design methods and standards for firefighting facilities, the effect of visible distance is the largest, In the case where the delay in entering the platform of the fire train was not taken into account, the ASET was analyzed to be about 800 seconds when the air flow rate was 4 × 833 m³/min. The estimated number of deaths varies greatly depending on the location of the vehicle of fire train, In the case of a fire occurring in a vehicle adjacent to the stairs, it is shown that the increase is up to three times that of the vehicle in the lead. In addition, when the smoke control flow rate increases, the number of fatalities decreases, and the reduction rate of the air supply method rather than the exhaust method increases. When the supply flow rate is 4 × 833 m³/min, the expected number of deaths is reduced to 13% compared to the case where ventilation is not performed. As a result of the risk assessment, it is found that the current social risk assessment criteria are satisfied when smoke control is performed, and the number of deaths is the flow rate 4 × 833 m³/min when smoke control is performed at 29.9 people in 10,000 year, It was analyzed that it decreased to 4.36 people.