• 대한교통학회지
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• 제25권2호
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• pp.83-93
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• 2007

도시 가로 설계에서 보행자와 자동차는 동등하게 고려되어야 한다. 그러나 현 도로 설계 기준은 자동차의 이동과 접근성에 기반한 도로 기능 분류 체계에 보도 설계를 적용하고 있어 보행자의 관점을 중심으로 둔 설계 방안이 절실히 요구된다. 이런 맥락에서 본 연구는 도시 보도 설계 단계에서 보행자 서비스수준을 고려할 것을 제안하였다. 그러나 현 도로용량편람에 제시된 기준은 보행 속도 등 보행 교통량에 기반하여 보행서비스수준을 평가토록 하고 있으나 도시 도로 설계 실무에서 보행 교통량은 거의 예측하지 않고 있으며, 도시부의 대다수 가로의 보도에서 보행 통행량 기반의 서비스수준 평가는 매우 드물게 경험하고 있어 서비스수준 평가 범위가 매우 제약되었다고 본다. 본 연구는 마주보고 통행하는 보행자들이 상충 시 경험하는 쾌적 수준에 기반한 보행 서비스수준 평가기준을 검토하고, 이를 용도지역별로 조사된 보행 통행 특성과 연계하여 도시 보도의 설계 단계에서 활용 가능한 서비스수준 평가기준을 제안하였다.

• 한국항해항만학회지
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• 제38권4호
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• pp.327-333
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• 2014

해상에서의 충돌사고 예방을 위한 충돌회피 원칙 및 각종 항법 등을 규정하고 있는 국제해상충돌예방규칙은 선박 간 충돌회피를 위한 초기대응 기준에 대해 대부분 선박 운항자 경험 및 주관적 판단에 의해 결정하도록 명시되어 있다. 그러나 초임 해기사나 학생들은 선박 운항 환경을 종합적으로 판단할 수 있는 경험 및 능력이 부족하므로, 충돌방지를 위한 최소한의 정량적인 초동조치 기준을 제시해 줌으로써 충돌사고를 효과적으로 예방할 수 있을 것으로 사료된다. 본 연구에서는 해상충돌예방규칙 및 기존 충돌위험 관련 연구 동향을 분석하였으며, 다양한 승선경력을 가진 선박 운항자들을 대상으로 설문을 실시하여 선박 간 조우관계에 따라 주관적으로 판단하는 최소 안전 이격거리와 초기대응의 개시 거리 및 변침각도를 조사하였다. 이러한 분석 결과를 기초로 선박 조우 관계별 충돌회피를 위한 초기 동작이 필요한 거리, 안전 이격거리 및 변침각도를 제시한다. 초기대응 기준은 해양사고 예방뿐만 아니라 점진적인 운항 기술의 향상에 기여할 것이다.

• 물과 미래
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• 제6권2호
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• pp.12-18
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• 1973

본 논문은 동기에 사역을 성토하기 위한 가능성을 검토하여 실제시공에 공헌하자는 데에 기 목적이 있다. 평상시의 성토기측은 다음과 같다. 1) 재료의 최대경은 30cm 이하로 하고 사분함유율은 중량비로서 60% 이하여야 한다. 2) 산포두께는 60cm 이하로 하고 각층마다 11ton 진동로 라로 칠회이상 다져서 상대밀도가 60%이상이 되게 하여야 한다. 그러나 동기의 사역성토를 가능하게 하기 위하여 상기의 평상시 기준에 아래와 같은 조건을 첨가하였다. 3) 사분함유율은 25% 이하로 하고 함수비는 4% 이하로 할 것. 4) 작업중에는 최대의 온도가 최소영하 $7^{\circ}C$이며 평균으로 영하 $3^{\circ}C$로하여 지속작업을 시행할 것 이상과 같은 기준하에서 각종 시험을 실시하고 기결과로서 댐의 안정성을 검토하여 본기준의 타당성을 입증하고 실제성토에 적용할 수 있음을 확인하였다.

• Environmental Analysis Health and Toxicology
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• 제5권1_2호
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• pp.51-55
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• 1990

The ultimate Wastes generated after being treated safely and properly were land-filled in Wha Sung Treatment Plant, that of specific hazardous Wastes. There are three kinds of wastes being landfilled, which are sludges, ashes, and solidificated wastes with cement. This research scrutinizes the variations of leachate which originated from landfilled wastes amount to 30,000 ton with analizing the constituent, pH and concentration of wastes once per month since september, 1987. Now, we have some conclusions as followings; 1. The longer retention time of wastes in landfill site and the more quantity of filling-up, the closer pH of leachate to alkalinity. 2. As the quantity of copper and its compounds is over 90 percent of constituents loundfilled wastes, so the copper of leachate goes above treatment criteria. 3. There lis relationship between pH of leachate and eruption of copper and its compounds. The higher pH of leachate, the more secured copper and its compounds. So, we learn that solidificated wastes with cement is more secured than sludges and ashes. 4. The pH and concentration of copper in leachate is low in July and August, this is passing phenomenon which diluted by rainfall in rainy days. 5. The quantities of cadmium and lead of leachate was not over the treatment criteria.

• 한국철도학회논문집
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• 제11권3호
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• pp.272-279
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• 2008

레일 표면 결함에 대한 유지보수의 중요성이 KTX의 운행에 따라 더욱 증대되고 있다. 이는 고속 운행시 레일 표면 결함은 레일의 피로수명 단축과 궤도의 열화 증속 및 승차감 저하를 유발하기 때문이다. 본 연구는 KTX의 운행현황을 고려하여 경부 고속선의 레일 연마 기준을 제안하였다. 이를 위해서 경부 고속선에서 UIC 60 레일 시편을 체취하여, 현미경에 의한 미세 조직을 조사하고 경도를 측정하였다. 레일 표면 결함을 유발하는 RCF에 영향을 미치는 인자들로 통과 톤수, 주행속도 및 궤도상태를 고려하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.848-853
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• 2005

The objective of this paper is to address to the providing an adequate noise and vibration solution, required for High Speed Rail while maintaining the stability criteria of the ChonAn station structure, the first constructed in Korean High Speed Railway. The significant acoustic pressure level will be induced by the high speed trains passing-by. Therefore, the high level study of this case is necessary. The acoustic pressure level of 85 dB(A) inside the ChonAn station is expected, and the spaces below concrete slab are not suitable for commercial purpose, thus installation of filtering systems (spring boxes containing viscous dampers, ballast mats and acoustic shield) are provided to reduce the effect of the noise and vibration to acceptable level of 55 dB(A). But, a major drawback of application of the previously conducted experimental results was that the actual effect of installation of filtering system was never been validated. Therefore, the acquisition of noise and vibration on the present structure were obtained and compared to the computer simulations. These predicted the behavior of the station reasonably well. Also, the installation of filtering systems gave the superior reduction on noise and vibration. This application is successfully adapted without scarifying stability criteria related to the structural stability including excessive deformations or displacements. Three traffic operation safety limits: deck vertical acceleration, deflection of the structure, and longitudinal displacement of the slab were satisfactory.

• 대한방사선기술학회지:방사선기술과학
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• 제43권2호
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• pp.105-114
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• 2020

This study aimed to assess of beam-matching accuracy for an 8 MV beam between the same model linear accelerators(Linac) commissioned over two years. Two models were got the customer acceptance procedure(CAP) criteria. For commissioning data for beam-matched linacs, the percentage depth doses(PDDs), beam profiles, output factors, multi-leaf collimator(MLC) leaf transmission factors, and the dosimetric leaf gap(DLG) were compared. In addition, the accuracy of beam matching was verified at phantom and patient levels. At phantom level, the point doses specified in TG-53 and TG-119 were compared to evaluate the accuracy of beam modelling. At patient level, the dose volume histogram(DVH) parameters and the delivery accuracy are evaluated on volumetric modulated arc therapy(VMAT) plan for 40 patients that included 20 lung and 20 brain cases. Ionization depth curve and dose profiles obtained in CAP showed a good level for beam matching between both Linacs. The variations in commissioning beam data, such as PDDs, beam profiles, output factors, TF, and DLG were all less than 1%. For the treatment plans of brain tumor and lung cancer, the average and maximum differences in evaluated DVH parameters for the planning target volume(PTV) and the organs at risk(OARs) were within 0.30% and 1.30%. Furthermore, all gamma passing rates for both beam-matched Linacs were higher than 98% for the 2%/2 mm criteria and 99% for the 2%/3 mm criteria. The overall variations in the beam data, as well as tests at phantom and patient levels remains all within the tolerance (1% difference) of clinical acceptability between beam-matched Linacs. Thus, we found an excellent dosimetric agreement to 8 MV beam characteristics for the same model Linacs.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2115-2124
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• 2011

The rail surface defects which are generated on repeated rolling contact fatigue are getting increased according to high speed, high density, and minimum weight. In addition, Increasing noise and vibration are affected by these also impact load generated as well. Because of this phenomenon, more serious and critical damages were occurred. In fact, in order to control them, the rail grinding were conducted. However, there are not enough researches to make an criteria of generating optimal rail grinding amount in Korea. This study evaluated how depth of hardening on rail surface is formed and suggested optimal rail grinding amount by RCF(rolling contact fatigue) test with generated contact pressure between KTX wheel and UIC60 rail by applying FEM analysis. Therefore, the amount was generated approximately 0.2mm/20MGT to maintain integrity of rail surface by getting rid of depth of hardening on rail according to rail accumulated passing tonnage.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.830-833
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• 2004

Hydraulic structures have been constructed with low cost concrete so as to increase the investment efficiency. But, it has caused to produce structures having excess internal voids inside concrete. As the construction of agricultural irrigation and drainage project is concentrated on off-farming season and scattered in wider area, variation of quality of structures is big and it caused increase of internal voids. Due to that reason, hazardous substance is passing rather freely through the voids causing occur of crack and accordingly life time of structures is getting shortened. It is necessary to make a thesis of design criteria for design strength to increase life time, range of variation of quality, strength of ready-mixed concrete proper to design strength, and water-cement ratio and air content.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.1104-1109
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• 2002

High speed railroad noise is one of the main causes of environmental impact. An estimate of the relevant noise levels is usually required in order to evaluate the noise barrier and the anti-noise trailer. This paper introduce the test procedure and the estimate for HST noise. The aim of this is to measure, by means of a test, the level of acoustic pressure present during the passing of a KTX(Korea Train Express), in order to satisfy the contractual requirements and the noise criteria. A number of measurements are carried out in order to estimate noise impact by HST along test track.