• The Korean Journal of Ecology
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• 제19권5호
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• pp.453-463
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• 1996

Diurnal changes of microclimatic conditions and tissue water relations were measured at two sites where Carpinus laxiflora and C. cordata were allopatrically distributed. The microclimatic conditions at a site where C. laxiflora was distributed produced severe water stress condition during summer months. Daily maximum temperature reached $30.4^\circC$ and the highest vapor pressure deficit was 1.31 KPa when 13 rainless days were continued. During this period soil water content decreased to below the field capacity even at a depth of 20 cm and xylem pressure potential also decreased to ­2.04 MPa. However, turgor potential was maintained more than 0.4 MPa. Patterns of stomatal conductance were changed with evaporative demand and soil water availability. On the other hand, microclimatic conditions at a site where C. cordata was distributed were moderate water strees condition compared with those at a site C. laxiflora was distributed. Though soil water content was maintained above field capacity C. cordata showed a remarkable decrease in turgor potential and stomatal conductance throughout the experiment. These results indicate that there is a difference in habitat characteristics between the two species and C. laxiflora is more resistant than C. cordata to water stress.

• 한국터널지하공간학회 논문집
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• 제16권2호
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• pp.125-133
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• 2014

본 연구에서는 지반 및 현장조건을 고려한 TBM 선정방법을 제시하였다. 지반, 환경, 가격조건별로 TBM 선정에 영향을 미치는 인자와 굴착장비를 선정 분류 하였다. 선정된 영향인자와 장비 간 가중치를 AHP기법을 적용하여 산정하였다. 선정된 영향인자의 분석결과 기본요소에서는 지반조건이 가장 중요한 영향요소로 확인되었으며, 세부요소로서 암반조건에서는 강도, 토사지반조건에서는 수압이 가장 중요한 인자로 확인되었다. 주변 환경조건에서는 시공성에 영향을 줄 수 있는 주변구조물 인접여부가 중요한 인자로 확인되었다. 마지막으로 도출된 각 영향인자별 가중치를 토대로 굴착현장에 적용 가능한 TBM을 선정하고 도출결과와 실제 현장에 적용된 장비의 비교를 통하여 본 연구에서 제안하는 방법에 대한 검증이 이루어 졌다.

• Earthquakes and Structures
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• 제9권5호
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• pp.983-997
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• 2015

This research evaluates the soil conditions for seismic stations situated in Romania using the horizontal-to-vertical spectral ratio (HVSR). The strong ground motion database assembled for this study consists of 179 analogue and digital strong ground motion recordings from four intermediate-depth Vrancea seismic events with $M_w{\geq}6.0$. In the first step of the analysis, the influence of the earthquake magnitude and source-to-site distance on the H/V curves is evaluated. Significant influences from both the earthquake magnitude and hypocentral distance are found especially for soil class A sites. Next, a site classification method proposed in the literature is applied for each seismic station and the soil classes are compared with those obtained from borehole data and from the topographic slope method. In addition, the success and error rates of this method are computed and compared with other studies from the literature. A more in-depth analysis of the H/V results is performed using data from seismic stations in Bucharest and a comparison of the free-field and borehole H/V curves is done for three seismic stations. The results show large differences between the free-field and the borehole curves. As a conclusion, the results from this study represent an intermediary step in the evaluation of the soil conditions for seismic stations in Romania and the need to perform more detailed soil classification analysis is highly emphasized.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.743-746
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• 2004

This research investigates experimentally an effect on the properties of the high flowing concrete according to variations of concrete materials and site conditions. Variations of sensitivity test are selected items as followings; (1)Concrete temperature, (2)Unit water(Surface moisture of fine aggregate), (3)Fineness modulus of fine aggregate, (4)Addition ratio of high-range water reducing agent. And fresh conditions of the high flowing concrete should be satisfied with required range including slump flow$(65{\pm}5cm)$, 50cm reaching time of slump flow$(4\~10sec)$, V-box flowing time$(10\~20sec)$, U-box height(min.300mm) and air content$(4{\pm}1\%)$. As results of sensitivity test, material variations and site conditions should be satisfied with the range as followings; (1)Concrete temperature is $10\~20^{\circ}C$ (below $30^{\circ}C$), (2)Surface moisture of fine aggregate is within ${\pm}0.6\%$, (3)Fineness modulus of fine aggregate is $2.6{\pm}0.2$ and (4)addition ratio of high range water reducing agent is within $1\%$ considered flow-ability, self-compaction and segregation resistance of the high flowing concrete.

• Nuclear Engineering and Technology
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• 제16권3호
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• pp.136-140
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• 1984

원자력발전소 사고 후 그 위험도를 평가하는 새로운 방법으로 몬테칼로 방법을 제시한다. 본 연구에서는 발전소 주위의 주민에게 주는 방사선의 영향을 평가하기 위하여 공기중의 확산계산에 부지에서 측정한 기상조건을 직접 사용하고 있다. 사고가 일어나는 순간에서의 화산조건은 주어진 기상자료로부터 분석된 pdf에 의하여 결정되고 그이후의 조건(풍향, 풍속, 안정도)은 마르코프 조건을 만족시킨다고 가정하였다. 예제로써 KNU-1의 냉각재 상실사고를 분석한 절과 50마일내의 주민이 받는 선량은 50퍼센트 신뢰도를 갖고 200 man-Sv이다.

• 한국실내디자인학회논문집
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• 제22권5호
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• pp.320-327
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• 2013

In order to maintain and protect professionalism in color planning, the present study examined the process at the time of realization of color through color inspection and supervision in the actual construction site and suggested plans for improvement. Reflecting the characteristics that the governing body of the construction site is not a private person but an organization, the present study aims to provide institutional measures so that the supervisor of color construction at the actual site of construction can propose concerns related to proper construction at the right time, and the matters cannot be decided from the perspective of a layman. The institutional measures are proposed through the case of application of a process at the construction stage of the color planning at the construction site of Muju Taekwondo Park. First, the process clarified where the responsibility lies by specifying special conditions concerning color inspection on the field guide and color contract. Second, the sample for building materials was selected after obtaining it from a company capable of supply and is appropriate for the planned unit cost so that it could play an important role in realizing colors at the stage of basic design. Third, the process of construction was ensured not by temporary selection of colors but by continuous approval of colors in consideration of the conditions of construction site through letter of approval of color at each stage and point of time. Fourth, coordination of various color elements of other fields including landscape, interior, and electricity ensured construction of the whole structure in one color concept. Fifth, color inspection through the mock up of the site will minimize erroneous construction and reconstruction and prevent decrease in productivity. Sixth, this study also suggested more comfortable and positive color environment through evaluation by experts and users. The researcher of this study expects that color experts actively participate in the stage of construction to contribute to improvement of the color environment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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• pp.183-188
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• 1995

Up to date, high-strength concrete pile which is producing in factory sells in the market. But according to the site and the construction conditions, the system to produce high-strength concrete pile directly in site is utilized in advanced country. Such the production system is the technique phenomenon very disirable in the side of quality control in site and the construction schedule, the time and the cost saving. This study is a fundamental experiment including concrete mixing design, non-autoclave curing method and the optimum condition to produce high-strengh concrete pile in site. As results of this study, High-strength concrete pile in site which target strength is 400kg/ $\textrm{cm}^2$ is able to produce it with optimum curing ciondition(75$^{\circ}C$, 9hr)and mixing design.

• 천문학회보
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• 제37권2호
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• pp.105.1-105.1
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• 2012

Moon and Mars have been explored by landers and rovers. Apollo missions landed five times on Lunar surface, and various rovers, including Curiosity landed and explored Mars. The selection of landing site have to be considered engineering and scientific side: the landing site to be available to land stably? the obstacle is not around the rover such as rocks and pothole? the landing site is valuable with scientific? And then landing site have to be the place which is satisfied two objects. We search the information about landing sites of Moon and Mars, and compile the conditions of landing sites. We expect that these data are useful when the landing site of Moon or Mars for Korean mission is selected.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.671-672
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• 2015

Due to harsh conditions of disaster areas, understanding of current feature of collapsed buildings, terrain, and other infrastructures is critical issue for disaster managers. However, because of difficulties in acquiring the geographical information of the disaster site such as large disaster site and limited capability of rescue workers, comprehensive site investigation of current location of survivors buried under the remains of the building is not an easy task for disaster managers. To overcome these circumstances of disaster site, this study makes use of an unmanned aerial vehicle, commonly known as a drone to effectively acquire current image data from the large disaster areas. The framework of 3D model reconstruction of disaster site using aerial imagery acquired by drones was also presented. The proposed methodology is expected to assist rescue workers and disaster managers in achieving a rapid and accurate identification of survivors under the collapsed building.

• 한국지반공학회논문집
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• 제28권3호
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• pp.25-34
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• 2012

최근 제안된 2-매개변수 지반분류 방법 및 지반 증폭계수가 국내 지반조건 및 지반증폭특성에 적합함을 검증하기 위하여 내진설계기준연구II, Eurocode-8, 현재 개정중인 미국 동부지역 NYC DOT 내진설계기준과 비교를 수행하였다. 유사한 조건의 지반 조건에 대하여 각 기준의 설계응답스펙트럼을 비교한 결과, 2-매개변수 지반분류, Eurocode-8, NYC DOT 내진설계기준은 일반적인 국내 지반특성인 단주기 영역의 증폭을 크게 고려하고 있는 반면, 내진설계기준 연구II는 장주기 영역의 증폭을 크게 평하는 것으로 나타났다. 추가적으로 경주시 $10km{\times}10km$ 지역내 50개 부지에 대한 지반응답해석 결과를 확보하고, 이를 내진설계기준연구II 및 2-매개변수 지반분류 방법에서 제안하는 지반 증폭계수와 2차원 공간적인 비교를 수행하였다. 단주기 및 장주기 증폭계수 모두에 대하여 내진설계기준연구II가 2-매개변수 지반분류 방법에 비하여 부지응답해석 결과와의 오차값이 월등히 큰 것으로 평가되어, 2-매개변수 지반분류 방법에서 제안하는 지반 증폭계수의 타당성을 확인하였다.