• Wind and Structures
• /
• 제7권6호
• /
• pp.359-372
• /
• 2004

Wind tunnel model studies were carried out to determine the wind load distribution on tributary areas near the gable-end of large, low-rise buildings with high pitch planar and curved roof shapes. Background pressure fluctuations on each tributary area are described by a series of uncorrelated modes given by the eigenvectors of the force covariance matrix. Analysis of eigenvalues shows that the dominant first mode contributes around 40% to the fluctuating pressures, and the eigenvector mode-shape generally follows the mean pressure distribution. The first mode contributes significantly to the fluctuating load effect, when its influence line is similar to the mode-shape. For such cases, the effective static pressure distribution closely follows the mean pressure distribution on the tributary area, and the quasi-static method would provide a good estimate of peak load effects.

• 환경영향평가
• /
• 제12권4호
• /
• pp.281-290
• /
• 2003

The influence of land-use type on surrounding temperature was studied the relationships between land-use types and the air condition analyzing AWS (Automatic Weather Station) data of Seoul from KMA (Korea Meteorological Administration). The distribution of air temperature by land-use type has been influenced by the different heating and cooling rates. The difference of heating rates depending on the land-use type was largest at 2~3hours after sunrise and the difference of cooling rates was largest from 2hours before sunset to 2hours after sunset with its maximum at sunset. The difference of cooling rates is greatest in a clear and calm weather situation and the large difference in cooling rates between the green areas and built-up area is up to $1.5^{\circ}C/h$. By season, the difference of cooling rates is largest in fall and in turn spring, winter and summer. In a cloudy or rainy day, the difference in heating and cooling rates on land-use type is not distinct but the tendency is similar to a clear day. In all seasons, the rate of difference occurrence of the daily range of temperature between the green areas and built-up area was large, especially fall. In a fall with a clear and calm day, the magnitude of the daily range of temperature between the green areas and built-up area was largest.

• 한국지리정보학회지
• /
• 제27권1호
• /
• pp.52-66
• /
• 2024

본 연구는 공간구조의 체계정립 및 계획 실효성 확보를 위하여, 부산광역시를 대상으로 도시기본계획에서 설정된 도시 중심지의 경계를 설정하고 중심지의 역할과 위상을 진단함으로써 중심지의 공간 체계와 특성을 파악하는데 목적이 있다. 이를 위하여 선행연구를 통해 중심지의 특성을 나타내는 4개의 지표를 선정하였고 지리적 경계 분석에 강점이 있는 공간통계기법으로 중심지 경계를 도출하였다. 또한 도출된 중심지 경계를 활용하여 각 중심지가 부산광역시 공간구조에서 가지는 영향력과 잠재력을 진단하기 위해 중심지 특성 지표와 인구잠재력 함수를 이용하였다. 분석 결과 중심지에 따라서 규모의 차이가 크게 발생하였으며, 용도지역상 상업지역이 활성화되지 않은 미활용지역과, 상업지역을 넘어 주거·공업지역으로 확산되는 확장지역이 도시 중심지마다 다르게 나타났다. 중심지의 흡인력을 나타내는 잠재력 측정 결과에서도 인구잠재력이 강한 지역과 약한 지역이 나타났다. 따라서 중심지 기능 강화를 위해서는 중심지 위계특성과 영향력 측정 결과를 기반으로 체계적인 관리 및 계획적인 육성전략이 필요하다. 본 연구에서 분석된 결과는 지속가능한 도시성장체계 구축과 균형발전 및 중심지 기능 강화를 위한 역세권개발계획 및 공간혁신구역과 함께 미래의 다양한 도시계획 수요와 정책의 변화에 대응하기 위한 자료로 활용 가능할 것이다.

• 대기
• /
• 제21권1호
• /
• pp.45-55
• /
• 2011

A definition on the tropical cyclone (TC) that influenced the Korean Peninsula (KP), the KP-influence TC, is widely used in the TC communities, but its criterion is not clear mainly due to the ambiguity and subjectiveness of the term such as 'influence', which led to the inconsistent TC statistical analysis. This study suggests a definition and criterion on the TC approaching to the KP (KP-approach TC) additionally, which is more obvious and objective than the KP-influence TC. In this study, the criterion on the KP-approach TC is determined when the TC's center from the RSMC best track data encounters the box areas of $28^{\circ}N{\sim}40^{\circ}N$ and $120^{\circ}E{\sim}138^{\circ}E$. The range is chosen by finding a minimum area that includes all official KP-influence TCs except three TCs that affected the KP as a tropical depression (TD). Statistical analysis reveals that, among total 1,537 TCs that occur in the western North Pacific during 1951-2008, the KP-approach TC was 472, the KP-influence TC was 187, and the KP-landfall TC was 87. August was the month that the largest TCs approach and influence to the KP. Finally, this paper suggests to determine the KP-influence TC by the strong wind and heavy rain advisories in the KP based on the observation after the storm's passage.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2019년도 학술발표회
• /
• pp.152-152
• /
• 2019

This study demonstrates a novel approach of remotely sensed estimates of stream flow at fifteen hydrological station in the Han River Basin, Korea. Multi-temporal data of the European Space Agency's Sentinel-1 SAR satellite from 19 January, 2015 to 25 August, 2018 is used to develop and validate the flow estimation model for each station. The flow estimation model is based on a power law relationship established between the remotely sensed surface area of water at a selected reach of the stream and the observed discharge. The satellite images were pre-processed for thermal noise, radiometric, speckle and terrain correction. The difference in SAR image brightness caused by the differences in SAR satellite look angle and atmospheric condition are corrected using the histogram matching technique. Selective area filtering is applied to identify the extent of the selected stream reach where the change in water surface area is highly sensitive to the change in stream discharge. Following this, an iterative procedure called the Optimum Threshold Classification Algorithm (OTC) is applied to the multi-temporal selective areas to extract a series of water surface areas. It is observed that the extracted water surface area and the stream discharge are related by the power law equation. A strong correlation coefficient ranging from 0.68 to 0.98 (mean=0.89) was observed for thirteen hydrological stations, while at two stations the relationship was highly affected by the hydraulic structures such as dam. It is further identified that the availability of remotely sensed data for a range of discharge conditions and the geometric properties of the selected stream reach such as the stream width and side slope influence the accuracy of the flow estimation model.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1998년도 추계종합학술대회 논문집
• /
• pp.67-70
• /
• 1998

In this paper, an interference analyzer for communication and/or broadcasting services is developed and presented based on Monte Carlo technique, which is now under study in the International Telecommunication Union(ITU). Monte Carlo technology is a statistical approach which functions by considering many trials. For each simulation trial, a scenario is built up using a number of different random variables, such as signal and interference strengths, transmitting and receiving antenna heights, antenna gains, etc.. Furthermore, this paper shows and application example of the analyzer to examine interference influence of the PCS(IS-95) base stations affecting to the IMT-2000 FDD base station, depending on serveral service environments like rural, suburban, and urban areas. The wave propagation model used in this simulation is the modified Hata model, which is known to the suitable to Korean environments.

• 한국철도학회논문집
• /
• 제6권1호
• /
• pp.73-79
• /
• 2003

The Korean high speed railroad is scheduled to open in 2004. For railroad-based integrated transfer system, it is essential to develop the intermodal information system for easy transfer to other travel modes. The understanding of mode choices by KTX passengers is crucial for the intermodal transportation planning. Recent development of Intelligent Transportation Systems(ITS) made it possible for railroad users to access the transportation information in a cabin or waiting areas at the station. Development of intermodal transportation information system will influence the relative demand for traveling by train from competing other transportation modes. The research is focused on a general overview of the ITS with an emphasis on intermodal transportation information system.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2003년도 춘계학술대회 논문집
• /
• pp.133-138
• /
• 2003

The Korean high speed railway is scheduled to open in 2004. For railway-based integrated transfer system, it is essential to develop intermodal information system for easy and better transfer to other travel modes. An understanding of mode choices by KTX passengers is crucial for the intermodal transportation planning. Recent development of Intelligent Transportation System made it possible for railroad users to access the information in a cabin or waiting areas at the station. Development of intermodal transportation information system will influence the relative demand for traveling by train from competing other transportation mode. The research is focused on a general overview of the ITS with an emphasis on intermodal transportation information system.

• Asian-Australasian Journal of Animal Sciences
• /
• 제25권4호
• /
• pp.584-591
• /
• 2012

To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05) higher % of birds in the range (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly more using the shelterbelts in the afternoon than in the morning. Approximately 17 times more birds used the forage areas compared to the control area in the corresponding range. There were 8 times more birds using a hay bale enriched area compared to the area with no hay bales. The use of forage sources (including hay bales) were the most successful method on-farm to attract birds into the range followed by shelterbelts and artificial shade. Free range egg farmers are encouraged to provide pasture, shaded areas and shelterbelts to attract birds into the free range.

• 한국농림기상학회지
• /
• 제8권4호
• /
• pp.242-249
• /
• 2006

육상생태계에 나타날 수 있는 기후변화의 영향을 평가하기 위해 생태계모형의 사용이 보편화되고 있다. 작물생육모형의 경우 포장단위로 적용할 수 있으므로 기후변화정보만 적절한 공간단위로 제공된다면 경관규모에서 상세한 공간변화를 예측할 수 있다. 경기북부지역은 청정환경과 함께 고품질 콩 재배에 알맞는 기후지대이지만 기후변화에 의해 이 지역 내 콩 재배단지가 어떤 영향을 받을지 궁금하다. 향후 100년간(2011-2100) 예상되는 기후조건에서 선발된 10ha 이상 규모의 342개 단지를 대상으로 CROPGRO-Soybean에 의해 조중만생 콩 품종의 생육을 모의하였다. 이를 위해 3개 기후학적 평년(2011-2040, 2041-2070, 2071-2100)에 대해 월별 30m 격자형 기후변화 자료로부터 각 재배단지의 일 최고 및 최저 기온, 강수량, 강수일수, 일사량을 추출하고, 각 평년별로 일기상자료를 통계학적 방법에 의해 무작위로 30년치씩 생성하였다. 미래 3개 평년의 기상자료에 의해 생육모형을 구동하여 342개 재배단지의 생장, 발육, 수량특성을 모의한 결과 온난화가 진행될수록 콩의 개화기와 성숙기가 단축되며, 전체적인 생육기간은 $7{\sim}9$일 정도 줄어들었다. 수량은 조중생종의 경우 온난화에 따라 $1{\sim}15%$ 정도 감소하였는데 반해 만생종은 증가 후 감소하였다. 그 결과 현존하는 재배구역의 남북간 생산성 차이가 미래에는 크게 감소하거나 품종에 따라 역전되는 현상이 기대된다.