• 대한교통학회지
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• 제12권4호
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• pp.21-33
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• 1994

The grade is a very significant factor in designing the bikeways. It affects the cyclist's maneuverability as well as route selection. The objective of this paper is to provide the vertical length by grade for bikeway. Field experiments were conducted by primary school children and university students to collect and analyze bike's climbing capability by grade. Combined data suggests that the desirable vertical length is 360m for 3% grade, 220m for 4%, 160m for 5%, 120m for 6% and 90m for 7% grade.

• 한국도로학회논문집
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• 제15권4호
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• pp.177-186
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• 2013

PURPOSES: The purpose of this study theoretically reviews vertical grade deriving process in super high speed environment and compares overseas design criteria with Domestic Standardization also draws suitable vertical grade design criteria of high standard for Domestic Circumstances in Korea. METHODS : By researching domestic vehicle registration status, calculating typical vehicle, using Vissim which is traffic simulation program, Speed-distance curve of the vehicle is derived under each design speed condition. Through Speed-distance curve, estimating critical length of grade and considering critical length of grade, maximum longitudinal incline is proposed. RESULTS : The result of domestic vehicle registration status, the typical vehicle for deriving vertical grade is calculated based on gravity horsepower ratio 200 lb/hp. For calculating critical length of grade, according to change speed of uphill entry, speed-distance curve is derived by using Vissim. Critical length of grade is calculated based on design speed 20 km/h criteria which is point of retardation. Estimated critical length of grade is 808 m and based on this result, maximum longitudinal incline was confirmed in the design speed between 130km/h to 140km/h. CONCLUSIONS: The case of the typical vehicle(truck) which is gravity horsepower ratio 200 lb/hp, maximum longitudinal incline 2% is desirable at the super high speed environment in the design speed between 130km/h to 140km/h.

• 대한교통학회지
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• 제25권5호
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• pp.79-90
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• 2007

도로의 최대종단경사는 차량의 등판능력에 좌우된다. 과거에 비해 차량의 성능이 좋아질수록 도로의 최대종단경사는 조정될 수 있다. 하지만, 미국(AASHTO, 1990, 2004)에서는 설계기준트럭이 300lb/hp에서 200lb/hp로 성능이 상승했음에도 불구하고, 적용되는 최대 종단경사는 거의 변화가 없다. 따라서, 현재 차량의 성능을 고려한 최대종단경사의 검토 및 조정의 검토가 필요한 실정이다. 특히 국내의 지형은 산악지가 많고, 험준한 지역이 많으므로 실정에 맞도록 최대종단경사의 검토가 필요하다. 본 연구에서는 차량의 성능의 개선과 도로 설계자가 당면한 결정의 문제를 인식하고 세계 각국의 지형과 최대종단경사 적용기준을 비교하여 우리나라의 최대종단경사의 적정성을 확인한다. 또한, 교통시뮬레이션 프로그램을 이용하여 차량의 성능향상에 따른 새로운 트럭 성능곡선을 토대로 최대종단경사를 판단한 결과 $1{\sim}2%$ 정도 종단경사 완화가 가능한 것으로 판단한다.

• 해양환경안전학회지
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• 제5권2호
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• pp.57-65
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• 1999

The in situ observations and the seawater analyses were conducted at all seasons from July 1996 to April 1999 for the purpose of describing the characteristics of seasonal variations of water quality in Mokpo harbour, Korea. Vertical stratification started to be formed in water column in spring, developed in summer and disappeared in fall. In summer, vertical density distribution of water column was found to be in stable structure with lower temperature and higher salinity of bottom water, and the vertical mixing of water between surface and bottom layers was restricted. In winter, however, surface water was found to be similar to bottom water in temperature and salinity, and water column was in unstable structure and in well-mixed condition between surface and bottom waters. The saturation percentage of dissolved oxygen(DO) in bottom water of inner part of Mokpo harbour at all seasons was shown to be decreased to the third grade or under the third grade of Korean standards of seawater quality. In particular, dissolved oxygen was oversaturated in surface water and undersaturated in bottom water in summer, due to stratification and organic pollution. The difference of DO concentration between surface and bottom waters was found to be greater in spring and summer than in fall and winter, due to stratification and photosynthesis of phytoplankton. The concentrations of chemical oxygen demand(COD) over the entire waters of Mokpo harbour were found to fluctuate from below the third grade to the first grade of Korean standards through all seasons and COD concentrations of same seasons were shown to be different year after year. In particular, in view of COD, the annual average seawater quality of Mokpo harbour was evaluated to be in third grade of Korean standards, due to organic pollution. The average COD of surface water was greater than that of bottom water in spring and summer, due to the autochthonous COD caused by production of phytoplankton in surface waters, while the average COD of surface water was similar to that of bottom water in fall and winter, due to the vertical mixing of water between surface and bottom layers.

• 한국도로학회논문집
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• 제7권4호
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• pp.141-150
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• 2005

지반위에 놓인 콘크리트 슬래브가 수직 하중을 받을 때 지반의 전단저항과 슬래브 하부와 지반과의 마찰 등에 의해 생기는 슬래브 하부의 수평저항을 고려하여 지반위에 놓인 콘크리트 슬래브의 거동을 분석하였다. 슬래브 하부의 수평 저항을 고려하기 위한 해석 공식을 유도하였고 퓨리에변환을 이용한 변환영역에서 이러한 공식의 해를 구하였다. 또한 판요소와 쉘요소를 이용한 유한요소법에 의한 모델을 개발하여 수치 해석 결과도 도출하였다. 이러한 해석 공식과 수치해석 모델을 이용한 해석 결과를 비교 분석하였고 매우 비슷한 결과가 도출되는 것을 알 수 있었다. 콘크리트 슬래브의 응력 분포에 슬래브 하부의 수평저항이 미치는 민감성을 여러 가지의 다른 슬래브의 두께, 탄성계수, 그리고 지반의 수직탄성계수 등을 고려하여 분석하였다. 해석 결과에서 슬래브 하부의 수평 저항은 슬래브의 응력에 매우 큰 영향을 미칠 수 있다는 것을 발견하였다.

• 한국주거학회논문집
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• 제18권5호
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• pp.133-141
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• 2007

The purpose of this study is to secure an evacuation time and to ensure safety by using an Ubiquitous Sensor Network computing when a fire breaks out at a super high-rise apartment housing. A super high-rise apartment housing that is a type of building to solve the problem of separation of the urban function and the phenomenon of hollowing out downtown has been on the increase, high-rise apartment housings occupying 52.7% of whole housings in 2005. However, if a fire breaks out, there would be serious damage since it accommodates many people and facilities as existence of vertical gigantism in the city. The architectural law in force has no clause on it which is universally applicable to general building, it is difficult to be applicable to a densely super high-rise apartment housing and there would be in danger of a resident's evacuation in the fire. Therefore, as a previous study to introduce an USN-based fire-warning facility and evacuation equipment, this study shows the improvement way after analyzing factors that are barriers to evacuaee's behavior of a super high-rise apartment housing and also shows establishment of the grade of vertical evacuation rank by SimuleX, one of the best computer simulation program.

• 한국도로학회논문집
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• 제16권5호
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• pp.173-182
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• 2014

PURPOSES : The purpose of the study is to a) explore the operating speed of trucks on rural highways affected by road geometry, and thereby b) develop a predictive model for the operating speed of trucks on rural highways. METHODS : Considering that most of the existing studies have focused on cars, the current study aimed to predict the operating speed of trucks by conducting linear regression analysis on the speed data of trucks operating on the linear-curved-linear portions of the road as a single set. RESULTS : The operating speed in the plane curve portion increased with the length of the curve, and decreased with a lower vertical grade and a smaller curve radius. In the straight plane portion, the operating speed increased with a larger curve radius(upstream), and decreased with an increase in the change of the vertical grade, depending on the length of the vertical curve. CONCLUSIONS : This study developed estimation models of truck for operational speed and evaluated the degree of safety for horizontal and vertical alignments simultaneous. In order to represent whole area of the rural highway, the models should be ew-analyzed with vast data related with road alignment factor in the near future.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1676-1682
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• 2008

The vertical curve of railway is installed in changing point where the gradient is more than a certain degree to ensure safe operation of train and comfort of passengers. As a result of CAD work with 3D coordination by using the existing equation, it was found that the simple equation about vertical curve installation suggested in the surveying engineering or railway regulations did not reflect theoretical curvature of circular curve in a case of steep grade and large vertical radius. In this study, for derive precision equation and transition curve about vertical curve, gradient parameters, equation of circles and transition curve equation were used, and it was verified by CAD that the derived equation is exactly satisfied with parameters of geometrical circular and transition curve. This equation could be used to provide more smoothing operation of train and comfort of passengers on vertical curves, especially in case that railway requires precision vertical alignment of track such as super high-speed railway, LRT or Maglev system.

• 대한수학교육학회지:수학교육학연구
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• 제14권1호
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• pp.111-127
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• 2004

본 연구는 기하 부분의 내용이 초등학교에서 중학교로 발전 전개되는 과정에서 일부 용어의 정의와 평행선과 각의 취급에 대하여 알아보았고, 교육과정에 제시된 관련내용을 분석하고 그에 따른 현행 교과서를 살펴보았다. 다음에 관련된 분야의 일부 외국교과서를 비교 분석하여 그 상황을 알아보았다 그 결과 현행 교과서 보다 바람직한 내용의 취급을 위해서는 우선 체계적인 학습을 할 수 있도록 교육과정에 보다 적합한 학습내용과 그 취급 방법을 제시해야만 하고, 그에 따라 교과서도 보다 적합하게 집필되어야 함을 제시하였다. 이를테면 용어의 정의는 반복하여 충분히 이해하도록 하고, 특히 교육의 다양성을 위해서 평행선의 성질에 관한 내용은 공준으로 도입하여 활용할 수도 있고, 우수한 학생들은 증명을 하여 활용할 수도 있도록 다양한 취급을 하는 것이 바람직함을 제시하였다. 그리고 특히 현행 교과서에서는 <7-나 단계에서 취급되고 있는 맞꼭지각의 성질과 평행선의 성질과 같은 연역적 추론에 의해서 증명될 수 있는 내용들은 18- 나 단계>로 이동을 하여 학습하는 것이 학습 체계의 연계에 바람직함을 제시하였다.

• Nuclear Engineering and Technology
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• 제54권11호
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• pp.4215-4219
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• 2022

The Cd_0.95Mn_0.05Te_0.98Se_0.02 (CMTS) ingot was grown by the vertical Bridgman technique at low pressure. All wafers showed high resistivity, which suggests potential as a room-temperature semiconductor detector. The resistivity of the CMTS planar detector was 1.47 × 10¹⁰ Ω·cm and mobility lifetime product of electrons was 1.29 × 10^-3 cm²/V. The spectroscopic property with Am-241 and Co-57 was evaluated. The energy resolution about 59.5 keV gamma-ray of Am-241 was 11% and the photo-peak of 122 keV gamma-ray from Co-57 was clearly distinguished. The result shows the first detector-grade CMTS in the world and proves CMTS's potential as a radiation detector operating at room temperature.