• Journal of Korean Society of Forest Science
• /
• v.108 no.1
• /
• pp.50-58
• /
• 2019

This study was carried out to analysis the landform characteristics of land creep areas in south Korea. Aspect ratio in 17 areas (approximately 46.0 %) among total land creep areas (37 areas) was ranged from 0.37 to 0.92. Also, aspect ratio in 36 areas (approximately 97.0 %) was less than 2. Longitudinal section form ratio of 15 areas (approximately 41.0 %) was less than 1.0, whereas 22 areas (approximately 59.0 %) were more than 1.0. Horseshoe hoof form in land creep areas were mostly appeared to flat land types, whereas convex terrain ground form was prevailed to micro-topography. Mean contour intervals were higher in micro-topography (mean 29.4 m, range 9.5 m ~ 83.2 m) than in except micro-topography (mean 24.3 m, range: 14.4 m ~ 59.4 m) in land creep areas. The contour intervals were slightly wider in micro-topography (mean 5.1 m, range: 4.9 m ~ 23.8 m) than in except micro-topography in land creep areas. The results indicate that contour intervals were significantly different (P < 0.05) between micro-topography and except micro-topography in land creep areas.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.37 no.6
• /
• pp.507-516
• /
• 2019

The investigation of land characteristics is an important task for the calculation of officially land prices and standard comparison table of land price. Therefore, it should be done objectively and consistently. However, the current investigation system is mainly done by researcher's subjective judgment. Therefore, the objectivity and consistency of this investigation is not guaranteed and questionable. In this study, we first defined the problem by analyzing the current land topography investigation method. In addition, in order to investigate the land topography, the geometry of the parcel is quantified by spatial information and applied to the decision tree based method(C4.5) to produce the final result. This study intended to extract the parcel characteristics data of the topographic by the use of spatial information and to apply the information to the C4.5, there by suggesting a method for addressing the problems. The findings showed approximately 93.5% between the results of topography classification estimated with rules learned by C4.5.

• Journal of Korean Society for Atmospheric Environment
• /
• v.24 no.6
• /
• pp.649-661
• /
• 2008

The impact of the detailed surface data on regional meteorological fields in complex coastal area is studied using RAMS. Resolutions of topography and land use data are very important to numerical modeling, because high resolution data can reflect correct terrain height and detail characteristics of the surface. Especially, in complex coastal region such as Gwangyang area, southern area in Korean Peninsula, high resolution topography and land use data are indispensable for accurate modeling results. This study investigated the effect of resolutions of terrain data using SRTM with 3 second resolution topography and KLU with 1 second resolution land use data. Case HR was the experiment using high resolution data, whereas Case LR used low resolution data. In Case HR, computed surface temperature was higher than Case LR along the coastline and wind speed was $1{\sim}2m/s$ weaker than Case LR. Time series of temperature and wind speed indicated great agreement with the observation data. Moreover, Case HR indicated outstanding results on statistical analysis such as regression, root mean square error, index of agreement.

• Journal of Ocean Engineering and Technology
• /
• v.20 no.5 s.72
• /
• pp.23-29
• /
• 2006

A quasi depth-varying mathematical model for wind-generated circulation in coastal areas, expressed in terms of the depth-averaged horizontal velocity components and free surface elevation was validated and used to understand the diurnal circulation process. The wind velocity is considered as a dominant factor for driving the current. In this paper, three-dimensional numerical experiments that included the land topography were used to investigate the mesoscale air flaw over the coastal regions. The surface temperature of the inland area was determined through a surface heat budget consideration with the inclusion of a layer of vegetation.A series of numerical experiments were then carried out to investigate the diurnal response of the air flaw and wind-generated circulation to various types of surface inhomogeneities.

• Journal of architectural history
• /
• v.23 no.5
• /
• pp.47-60
• /
• 2014

Urban-Hanok emerged as a result of urbanization of Hanok in the modern period. In particular, Urban-Hanok has been mass-produced from the early 1920s, when the population is concentrated in cities, until the middle. Large-scale development by the professional developer has been developed in large-scale land rather than individual client because housing shortage was serious problem. 11 Gahoe-dong was made in 1935-36 is representative Urban-hanok area of Bukchon. It was formed through division of large-scale Land in 1930's. In the 1930's, the large-scale development projects of Urban-Hanok was triggered by the two events. One is Land Investigation Project performed by the Japanese government to capitalization of property, another is the pro-japanese bought the large scale-land in Gahoe-dong at bargain price from The Japanese government. Each lot has still a topographical characteristics such as land-dividing quality, the way of development, characteristic quality of urban-tissue. 11 Gahoe-dong, Urban-hanok area was developed two ways. First, development have been adapted to the topography. The lots have reflected topographical conditions such as land cutting area, a retaining wall, land-diving was maintaining the original topography almost. Second, it was street oriented development. The lots have developed sequentially along the street. So, the lots's shape and size is different each. For this reason, this area distribute various type of Hanok.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.19 no.3
• /
• pp.233-240
• /
• 2013

Jakarta is the capital city of Indonesia which has problems of land subsidence with the rates of about 1 to 15 cm/year, up to 20-25 cm/year. The study has examined the land subsidence in Pantai Mutiara, Jakarta Bay which is a reclaimed area by using the Terrestrial LIDAR survey technique. The Terrestrial LIDAR survey results show that the survey site has mean elevation of 0.24 m with the highest elevation of 0.93 m and lowest - 0.35 m. Considering that AHHW (approximate highest high water) is 0.51 m, many areas of the survey site are lying below the AHHW. Pantai Mutiara area is showing various subsidence rates depending on sites although the site is relatively narrow and small (about 1 $km^2$). There is elevation differences of almost 1m within the site. In this study, key information including topography, dike height distribution, and future coastal flooding risk of the survey area was able to be provided by Terrestrial LIDAR survey conducted only once. Especially, as the 3D precision topography effectively conveys important messages relating to vulnerability of the site, policy makers and stakeholders can easily understand the situation of the site.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2006.05a
• /
• pp.1925-1930
• /
• 2006

A quasi depth-varying mathematical model for wind-generated circulation in coastal areas, expressed in terms of the depth-averaged horizontal velocity components and free surface elevation was validated and used to understand the diurnal circulation process. The wind velocity is considered as a dominant factor for driving the wind generated current. In this paper, three dimensional numerical experiments that included the land topography were used to investigate the mesoscale air flow over the coastal regions. The surface temperature of the inland was determined through the surface heat budget consideration with inclusion of a layer of vegetation. A series of numerical experiments were then carried out to investigate the diurnal response of the air flow and wind-generated circulation to various types of surface inhomogeneities.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.31 no.5
• /
• pp.20-30
• /
• 2003

This study is aimed at establishing the categories and items for ecological assessment and evaluation of the environmental friendliness of golf courses in the capital region of Korea. The categories and items for the assessment have been derived based on the existing literature and interviews with golf experts. This study covers 32 golf courses in the capital region of Korea that are available in terms of data and on-site surveys. In order to conduct a comprehensive assessment of the environmental friendliness of the golf courses, the assessment area was divided into 4 categories that include a total of 14 sub-categories. The 4 categories encompass 1) location, 2) topography, 3) vegetation, and 4) construction. As its sub-categories, the location category includes current land use and zoning in the National Land Use Management Law. Topography has 2 sub-categories in the damage ratio of existing topography, gradient, cut area, and slope height. The assessment of vegetation is largely based on site surveys in the categories of preservation of the existing vegetation, the use of natural resources and existing trees, the component ratio of native tree species, the multi-layered structure of vegetation, and the utilization of water purification plants. In the aspect of construction, afforestation on tile slopes and the utilization of existing surface soil were evaluated. The examination of comparative analysis among the 10 items as a ratio measure showed that the scores were low in the sub-categories of current land we, the use of existing trees, and the multi-layered structure of vegetation. However, the rating results were satisfactory in the 2 sub-categories including cut area, and the utilization of native tree species. Those proved to be contributing factors in the ecological health of the golf courses. According to correlation analysis of the 10 items to the overall ecological rating of each golf course, the sizes of the 32 golf courses were mainly affected by the damage ratio of existing topography, gradient, preservation of vegetation and slope height. This study has the initiative to conduct an ecological assessment of golf courses in the country based on site surveys. The study results revealed that location factors such as current land use, damage ratio of topography and gradient and topographical factors were the main factors affecting the environmental friendliness of golf courses. This indicates indicating the significance of these factors in the future construction practices of golf courses. Furthermore, this study raises the need for follow-up studies to establish more detailed assessment criteria and to develop assessment techniques for areas such as slope afforestation and water purification plants that need a qualitative approach.

• Geophysics and Geophysical Exploration
• /
• v.20 no.3
• /
• pp.163-175
• /
• 2017

In land seismic exploration, irregular surface topography and weathering layer in near surface distorts the reflected signals of data. Therefore, typical land seismic data should be compensated for this distortion by static correction. To perform the static correction, near-surface velocity is required, which can be obtained by seismic refraction survey. However, land seismic data is often acquired in a limited form of geometry depending on the equipment availability, accessibility condition, and permission for the survey site. In this situation, refraction analysis should be performed using reflection data because it is impossible to acquire refraction-oriented data due to limited source and receiver geometry. In this study, we aimed to analyze the reliability of the results obtained by refraction traveltime tomography when using reflection data with a limited number of sources and receivers from irregular surface topography. By comparing the inversion result from irregular topography with that from flat surface, we found that the surface topography affects the reliability of the inversion results to some degree. We also found that the number of sources has little effect on the inversion results unless the number of sources are very small. On the other hand, we observed that velocity distortion occurred in the overlapped part of receiver arrays when using a limited number of receivers, and therefore suggested the size of the least overlapping ratio to avoid the velocity distortion. Finally, we performed numerical tests for the model which simulates the surface topography and acquisition geometry of the survey region and verified the reliability analysis of inversion results. We identified reliable areas and suspicious area of the inverted velocity model by applying the analysis results to field data.

• Asian Journal of Atmospheric Environment
• /
• v.10 no.1
• /
• pp.42-50
• /
• 2016

This study presents a performance evaluation of four different land surface models (LSM) available in Weather Forecast Research (WRF). The research site was located in Haean Basin in South Korea. The basin is very unique by its geomorphology and topography. For a better representation of the complex terrain in the mesoscale model were used a high resolution topography data with a spatial resolution of 30 meters. Additionally, land-use layer was corrected by ground mapping data-sets. The observation equipments used in the study were an ultrasonic anemometer with a gas analyzer, an automatic weather station and a tethered balloon sonde. The model simulation covers a four-day period during autumn. The result shows significant impact of LSM on meteorological simulation. The best agreement between observation and simulation was found in the case of WRF with Noah LSM (WRF-Noah). The WRF with Rapid Update Cycle LSM (WRF-RUC) has a very good agreement with temperature profiles due to successfully predicted fog which appeared during measurements and affected the radiation budget at the basin floor. The WRF with Pleim and Xiu LSM (WRF-PX) and WRF with Thermal Diffusion LSM (WRF-TD) performed insufficiently for simulation of heat fluxes. Both overestimated the sensible and underestimated the latent heat fluxes during the daytime.