• 터널과지하공간
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• 제16권6호
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• pp.506-525
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• 2006

복잡한 지층 및 지질구조 특성을 보이는 대규모 절취사면의 경우 설계 시의 조사 및 시험의 한계성 등으로 인하여 지반특성파악 및 설계정수의 산정이 어려워 시공 중 사면활동이 빈번하게 발생하고 있다. 이러한 경우 시공 중 절취상태에서 지반특성에 부합된 최적의 조사 및 분석 과정을 통하여 합리적인 대책방안을 강구해야 한다. 본 연구에서는 변성퇴적암류로 구성된 현존 국내 최대 규모의 대절토사면 (연장520 m, 최대절취고 약 122 m, 최대법면길이 약 212 m)을 대상으로, 활동이력분석과 시공 중 지반조사를 통하여 사면의 붕괴원인분석에 관한 시공사례연구를 실시하였다. 원설계 시 대상사면의 경사는 발파암 기준 1:0.7을 적용하여 일부 시공하였으나 절취과정에서 지질요인, 강우 등 안정성을 저해하는 제반 요인에 의하여 다수의 지반활동이 발생하였으며, 계속적인 지반활동으로 인하여 대규모 산사태가 예상되는 매우 위험한 지반상태를 나타내고 있어. 이에 총 3차의 설계변경을 통해 사면의 장기 안정성을 확보하였다. 이러한 사례연구를 통하여, 본 지반조건과 유사한 지질 및 불연속면 특성을 나타내는 암반사면에 대한 안정성 분석, 평가 및 대책방안 수립을 위한 참고 자료가 되기를 기대한다.

• Geosciences Journal
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• 제22권6호
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• pp.1041-1052
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• 2018

A single-well push-drift-pull tracer test using two different tracers ($SF_6$ and salt) was performed at the Environmental Impact Test (EIT) site to determine suitable locations for monitoring wells and arrange them prior to artificial $CO_2$ injection and leak tests. Local-scale estimates of hydraulic properties (linear groundwater velocity and effective porosity) were obtained at the study site by the tracer test with two tracers. The mass recovery percentage of the volatile tracer ($SF_6$) was lower than that of the non-volatile tracer (salt) and increased drift time may make degassing of $SF_6$ intensified. The $CO_2$ leakage monitoring results for both unsaturated and saturated zones suggest that the $CO_2$ monitoring points should be located near points at which a high concentration gradient is expected. Based on the estimated hydraulic properties and tracer mass recovery rates, an optimal $CO_2$ monitoring network including boreholes for monitoring the unsaturated zone was constructed at the study site.

• 한국수소및신에너지학회논문집
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• 제17권3호
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• pp.263-271
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• 2006

In this study, $20\;Nm^3/hr$ scale compact hydrogen generator which can be apply to the hydrogen station was manufactured and tested. The design of $20\;Nm^3/hr$ scale compact hydrogen generator was upgraded on the base of $5\;Nm^3/hr$ scale plate hydrogen generator concept stacking the plate reactors. Ideas for improving system efficiency such as heat recovery from the exhaust, exhaust duct which is especially design for plate type reactor, reinforcement of insulation, enlargement of heat exchange area of reactor, introduction of desulphurizer reactor and PROX rector in a compact design etc. were applied. From the performance test, we can learn that the $20\;Nm^3/hr$ scale compact hydrogen generator can be operated steadily at 100% road condition and the methane conversion of over 94%(at S/C=3.75) was obtained. This result shows that the concept of plate type hydrogen generator can be scale-up to the $20\;Nm^3/hr$ scale and fit for hydrogen generator for on site hydrogen station application.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (B)
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• pp.52-54
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• 2003

Measurement is used to improve software process and to help calculating software quality. It makes software project to be control and help producing software. Measuring software scale becomes important target in software development. LOC is used to measure the size intentioned aspect and function point is used to measure the function intentioned aspect. This paper discusses measurement method using function point, which fullows proposed rule, and degree of GUI (Graphical User Interface) accesses achieved by applying this measurement to web page. Applying proposed rules to web pages (specially that use much GUI such as shopping mall or auction site), there is advantage that calculate site changes on numerical value by measuring GUI degree when do site administration or update.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.81-85
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• 1998

In the present study, the design method of containment walls is proposed by utilizing an existing site. The selected remedy for the Source Area of Operable Unit 2 at Hill Air Force Base stipulated containment of the pure-phase trichloroethylene contamination. The in-place-mixed wall construction was selected because of the irregular topography, small area of the site, and the requirement to reach depths of greater than 90 feet below ground surface. Bench-scale compatibility studies were performed for the containment wall mix design on three commercial bentonite clays. The samples were subject to screening tests and long-term tests for evaluation of changed soil properties when exposed to the contaminated groundwater.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1318-1327
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• 2008

Geotechnical sites in urban areas may have embedded structures such as utility lines and underground concrete structures, which cause difficulties in site investigation. This study is a preliminary research to establish knowledge base for developing an optimal technique for site investigation in urban areas. Surface-wave method and resistivity survey, which are frequently adopted for non-destructive site-investigation for geotechnical sites, were investigated to characterize effects of adjacent structures. In case of surface wave method, patterns of wave propagation were investigated for typical sets of multi-layered geotechnical profiles by numerical simulation based on forward modeling theory and field experiments for small-size model tests and real-scale tests in the field. In case of resistivity survey, 3-D finite element analyses and field tests were performed to investigate effects of adjacent concrete structures. These theoretical and experimental researches for surface-wave method and resistivity survey resulted in establishing physical criteria to cause interference of adjacent structures in site investigation at urban areas.

• 한국도로학회논문집
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• 제12권2호
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• pp.129-136
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• 2010

현행 주차장법상의 부설주차장 설치기준은 위락시설, 문화 및 집회시설, 단독주택, 공장 등 설치 대상 시설물을 9개 그룹으로 분류하고, 그룹 내 시설물에 대해서는 동일한 설치기준이 제시되어 있다. 지자체는 필요에 따라서 지자체 조례로 시설물의 종류를 세분하거나 설치기준의 2분의 1의 범위(${\pm}$50%) 안에서 이를 강화 또는 완화할 수 있도록 되어 있다. 최근 건축물의 종류가 다양해지고 기능이 혼재되어 같은 그룹에 속하더라도 시설물에 따라 주차장설치기준을 세분화할 필요가 있으나, 대부분 지자체의 경우 체계적이고 일관된 기준 없이 주차장법에서 제시된 시설분류기준에 강화된 획일적인 설치기준을 조례에 적용하고 있다. 특히, 산업단지 내 위치한 대규모 첨단제조시설의 경우 공정이 자동화되어 건물규모대비 근무인력이 소수임에도 불구하고 이에 대한 별도의 세부적인 구분없이 기타시설 또는 공장시설로 분류되어 일반 제조공장과 동일한 일괄적 기준을 적용하고 있다. 따라서 본 연구에서는 현장조사를 통해 산업단지 내 공장시설에 대한 기존 주차원단위 산정에 대한 문제점을 분석하고, 이를 해결하기 위해 방안으로 용도 및 규모특성을 고려한 부설주차장 설치기준 개선방안을 제시하였다.

• Environmental Engineering Research
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• 제19권3호
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• pp.269-274
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• 2014

On-site sanitation systems are typically installed to treat grey and toilet wastewaters in areas without sewer and centralized treatment systems. It is well known that, due to inappropriate design and operation, treatment performance of these systems in developing countries is not satisfactory in the removal of pathogens and organic matters. This research aimed to investigate the hydraulic conditions occurring in some on-site sanitation systems and the effects of hydraulic retention times (HRTs) on the system performance. The experiments were conducted with a laboratory-scale septic tank (40L in size) and an actual septic tank (600L in size), to test the hydraulic conditions by using tracer study with HRTs varying at 12, 24 and 48 hr. The experimental results showed the dispersion numbers to be in the range of 0.017-0.320 and the short-circuit ratios in the range of 0.014-0.031, indicating the reactors having a high level of sort-circuiting and approaching complete-mix conditions. The removal efficiency of $BOD_5$ was found to be 67% and the $k_{30}$ values for $BOD_5$ was $2.04day^{-1}$. A modified complete-mix model based on the relationship between $BOD_5$ removal efficiencies and HRTs was developed and validated with actual-scale septic tank data having a correlation coefficient ($R^2$) of 0.90. Therefore, to better protect our environment and minimizing health risks, new generation toilets should be developed that could minimize short-circuiting and improving treatment performance.

• 문화기술의 융합
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• 제8권6호
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• pp.775-785
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• 2022

이 연구는 소규모 건설현장 근로자의 화재안전관리 운영실태를 분석하고 문제점을 도출하여 개선방안을 제시함으로써, 향후 이들이 효율적으로 활용하기 위한 실무적 기초자료를 제시함을 목적으로 연구를 수행한 결과, 다음과 같은 결론을 얻었다. 첫째, 소규모 건설공사현장 근로자는 건설기능인력의 연령대가 고령자이고, 종사경력은 건설기능력이 짧았으며, 직종은 대다수가 건축공종에 작업을 하고 있으며, 고용형태는 비정규직 일당제로 근무를 하고 있는 것으로 분석 되었다. 둘째, 소규모 건설공사현장 근로자들의 화재안전관리 개선방안으로 화재 위험성 요인에 대한 허가와 관리를 체계화하고, 화재위험관리를 위해 소방안전관리자를 배치하여 관리감독하는 장치가 필요하겠으며, 화재시 다양한 피난통로 확보와 화재 발생을 건설공사 현장 내 모든 작업자들에게 알릴 수 있는 비상경보설비를 갖추고, 피난경로 접근과 시야 확보가 취약한 지하공간에 대해서는 간이피난유도선과 비상조명등을 임시소방시설로 설치를 강화하는 방안을 제시하였다. 또한, 현실적인 대피훈련, 화재VR훈련, 흥미있는 교육프로그램 개발을 통해 산업재해를 줄이는 방안이 필요하다.

• 한국안전학회지
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• 제35권2호
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• pp.67-75
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• 2020

Due to various industrial accident that occur to the staff in the broadcasting production sites, the issue of safety at the broadcast production site is becoming a social issue. Nevertheless, not many researches have been carried out on the actual conditions of the staff's production environment and its safety issues. Therefore, the purpose of this study was to prepare a countermeasure based on engineering knowledge by analyzing working environment to improve the poor working environment of staff. First, this study analyzed statistical data of industrial accidents over the past five years to find out the current status of disasters at broadcasting production sites. As a result, the intensity of the accident was not weak in that the loss days was more than one month in 85% of accident. In addition, the type of accident was high in the fall/trip accidents. Second, this study visited 10 broadcasting production sites for risk assessment. By analyzing the characteristics of the working environment and 104 questionnaires, we predicted the types of accidents that can occur in the broadcasting production site. As a result, accident types such as fall, collision, and trip were relatively high, similar to the characteristics of construction site. Third, it was possible to quantify the scale of the risk in the broadcasting production, and as a result, the quantity of temporary structure and accident risk were proportional. In other words, this study analyzes broadcasting work environment and defines risk factors based on safety engineering knowledge. Finally, this study suggested a guideline to improve the safety of the broadcasting production site.