• Atmosphere
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• v.31 no.5
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• pp.473-488
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• 2021

A new physical/statistical diagnostic downscale model has been developed for use to improve near-surface air temperature forecasts. The model includes a series of physical and statistical correction methods that account for un-resolved topographic and land-use effects as well as statistical bias errors in a low-resolution atmospheric model. Operational temperature forecasts of the Local Data Assimilation and Prediction System (LDAPS) were downscaled at 100 m resolution for three months, which were used to validate the model's physical and statistical correction methods and to compare its performance with the forecasts of the Korea Meteorological Administration Post-processing (KMAP) system. The validation results showed positive impacts of the un-resolved topographic and urban effects (topographic height correction, valley cold air pool effect, mountain internal boundary layer formation effect, urban land-use effect) in complex terrain areas. In addition, the statistical bias correction of the LDAPS model were efficient in reducing forecast errors of the near-surface temperatures. The new high-resolution downscale model showed better agreement against Korean 584 meteorological monitoring stations than the KMAP, supporting the importance of the new physical and statistical correction methods. The new physical/statistical diagnostic downscale model can be a useful tool in improving near-surface temperature forecasts and diagnostics over complex terrain areas.

• Industry Promotion Research
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• v.7 no.1
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• pp.75-80
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• 2022

Cui Bu (1454~1504 BC), named Yuanyuan, named Jinnan. Served as the deputy manager of the Korean King Chosun Hongwenguan (fifth grade official). In 1487, on the way to Jeju Island to perform official duties, because his father died, he went home from the funeral on the third day of the first lunar month in 1488, but was unfortunately on the way. Encountered a storm, and drifting at sea for nearly half a month, he landed at the "Linhai County Boundary of Taizhou Prefecture, Zhejiang Province, Datang Kingdom" (now Sanmen County). Later, Cui Bu went to Hangzhou by land near Taizhou, where he landed, then via Hangzhou, took a boat along the Beijing-Hangzhou Grand Canal to Beijing, and from Beijing by land through Shanhaiguan, and returned to his country via the Yalu River. Cui Bu stayed in China for four and a half months, 136 days, and traveled nearly 9,000 miles. After returning to China, he wrote the book "Piaohailu" in Chinese. This diary-style book has a total of more than 50,000 characters, covering politics, military, economics, culture, transportation, and local customs in the early years of Hongzhi in the Ming Dynasty. The situation is an important document for studying China's Ming Dynasty coastal defense, political system, justice, canals, cities, topography, and folklore.

• Wind and Structures
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• v.39 no.4
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• pp.305-311
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• 2024

This paper reviews measurements of wind profiles in the atmospheric boundary layer in strong wind (thermally neutral) conditions over open water and the ocean, and the variation of the roughness parameters with mean wind speed. Based on the wind data recorded on the coast of the island of Frøya (Norway) in the 1980s, and dropwindsonde profiles in hurricanes, the paper shows that 'capping', or saturation, of the surface drag coefficient becomes apparent at a mean wind speed at 10m height of about 25 m/s. Wind speed models used in the offshore industries were investigated, (the ISO model, the API 'tropical cyclone' model and the IEC model). The ISO model, although based on good quality data from Frøya, does not allow for the saturation of the roughness above about 25-30 m/s, even though that was apparent in the Frøya data. 'Capping' of the aerodynamic roughness length for wind speeds greater than 28 m/s is represented appropriately in the API 'tropical cyclone'model, and hence the model represents the mean wind properties reasonably well in severe tropical cyclone conditions. However, the turbulence intensities in the API 'tropical cyclone' model, based on over-land measurements (ESDU), are overpredicted for winds over the ocean, at heights above 20m. The IEC models are entirely based on over-land measurements, and hence are not representative of over-water conditions such as those required for offshore wind farms. New model profiles for over-ocean strong winds are proposed for wind speeds up to hurricane strength, based on the ISO profiles, but with capping of the surface drag coefficient at a value of 0.0025, at a mean wind speed at 10m height of 25 m/s. The proposed turbulence intensity model is also a revision of the ISO profile, also with capping above 25 m/s. The proposed model profiles are in better general agreement with recorded data in strong winds than those currently specified in international standards, and are applicable to all wind speeds in synoptic-scale events, including those in tropical cyclones, typhoons and hurricanes. As well as the Frøya data, the revised strong-wind models are supported by measurements from Atlantic hurricanes, gales in the North Sea, landfalling typhoons in Japan and Cyclone 'Yasi' in Queensland, Australia.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.3
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• pp.165-176
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• 2018

To solve the inconsistencies between realistic boundaries and the cadastral record boundaries, the cadastral resurvey project has been funded by a large budget since 2012 and executed over a long period of time until 2030. However, if the causes of inconsistencies are not analyzed and addressed, these inconsistencies could possibly reoccur. Even though the causes of inconsistencies can be defined in several aspects, including regulations, surveying methods, and management of cadastre maps or survey results, and so on, this study focuses on analyzing the inconsistency problems in the management of cadastre maps or survey results. In order to resolve the problems in inconsistencies between the cadastre maps and survey results, the study proposes to develop the cadastre data model based on LADM (Land Administration Domain Model) to manage the cadastre maps and survey results in better ways. In order to proposed the Cadastre Data Model, we analyzed the cadastre management system implemented in Korea and identified requirements to resolve the problems in inconsistencies, which are considered in the proposed data model as follows: 1) cadastral management system based on individual parcels, 2) synthesis of a realistic boundary and cadastral record boundary, 3) management of official and sharing reference data, 4) consistent management of survey results and parcel boundaries, 5) temporal managements of parcel boundaries. In the end, this study proposes a cadastral data model based on the LADM to integrate and manage the cadastral surveying results of the new cadastral management system.

• Journal of Environmental Science International
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• v.14 no.11
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• pp.1015-1026
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• 2005

The southeastern coastal area of the Korean peninsula has a complex terrain including an irregular coastline and moderately high mountains. This implies that mesoscale circulations such as mountain-valley breeze and land-sea breeze can play an important role in wind field and ocean forcing. In this study, to improve the accuracy of complex coastal rind field(surface wind and sea surface wind), we carried out the sensitivity experiments based on PBL schemes in PSU/NCAR Mesoscale Model (MM5), which is being used in the operational system at Korea Meteorological Administration. Four widely used PBL parameterization schemes in sensitivity experiments were chosen: Medium-Range Forecast (MRF), High-resolution Blackadar, Eta, and Gayno-Seaman scheme. Thereafter, case(2004. 8. 26 - 8. 27) of weak-gradient flows was simulated, and the time series and the vertical profiles of the simulated wind speed and wind direction were compared with those of hourly surface observations (AWS, BUOY) and QuikSCAT data. In the simulated results, the strength of rind speed of all schemes was overestimated in complex coastal regions, while that of about four different schemes was underestimated in islands and over the sea. Sea surface wind using the Eta scheme showed the highest wind speed over the sea and its distribution was similar to the observational data. Horizontal distribution of the simulated wind direction was very similar to that of real observational data in case of all schemes. Simulated and observed vertical distribution of wind field was also similar under boundary layer(about 1 km), however the simulated wind speed was underestimated in upper layer.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.2
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• pp.149-155
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• 2011

As the depletion of land resources, the attention about marine resources has been focused on. Neighboring countries such as Japan and China to expand their marine territory invest more governmental money. The exact territorial sea baselines can be the scientific data which cad resolve the dispute between the neighboring countries. So, those territorial sea baselines should be maintained systematically and continuously. Because territorial sea baselines surveyed 10 years ago without updating, the review may be needed. In this study, we compared 2009 year surveying results with past territorial sea baselines results for reviews. As a results, Jeju Island represents a large difference. So, the outputs of territorial sea baselines around Jeju Island should be readjusted. Through this study, the ongoing maintenance of the territorial sea baselines is required. The continuing interest in the maritime boundary, as well as defend in terms of protection for undersea resources are needed.

• Atmosphere
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• v.30 no.3
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• pp.257-276
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• 2020

Faithful evaluation of the meteorological input is a prerequisite for a better understanding of air quality model performance. Despite the importance, the preliminary meteorological assessment has rarely been concerned. In this study, we aim to evaluate the performance of the Weather Research and Forecasting (WRF) model conducting a year-long high-resolution meteorological simulation in 2016 over the Seoul metropolitan area. The WRF model was configured based on a series of sensitivity simulations of initial/boundary meteorological conditions, land use mapping data, reanalysis grid nudging method, domain nesting method, and urban canopy model. The simulated results of winds, air temperature, and specific humidity in the atmospheric boundary layer (ABL) were evaluated following statistical evaluation guidance using the surface and upper meteorological measurements. The statistical evaluation results are presented. The model performance was interpreted acceptable for air quality modeling within the statistical criteria of complex conditions, showing consistent overestimation in wind speeds. Further statistical analysis showed that the meteorological model biases were highly systematic with systematic bias fractions (f_SB) of 20~50%. This study suggests that both the momentum exchange process of the surface layer and the ABL entrainment process should be investigated for further improvement of the model performance.

• Journal of Cadastre & Land InformatiX
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• v.45 no.1
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• pp.151-167
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• 2015

At present cadastral surveying is being driven fort combination of digitalized cadastral map accord with real cadastral boundary between cadastral resurvey area and World Geodetic System transformation about all country. So this study is conducted to newly establish items being needed in making digitalization of parcel boundary points based on the World Geodetic System in registration conversion surveying. For this study firstly management of mountainous districts Act, related laws and registration conversion-related laws and regulations are reviewd. Secondly, economical, administrative validation by using data from 12-branch companies of LX is analyzed. Thirdly, surveying method and procedure were established through experimental surveying on the two cases such as digital and analog area. Finally, through investigating standard of estimate about cadastral surveying, it was calculated amendment of registration conversion surveying fee based on World Geodetic coordinate System.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.4
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• pp.15-23
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• 2017

The WGS conversion project of cadastral drawing (promoted by the Ministry of Land) is not able to reflect the cadastral registration due to subtle differences such as area and location. When converting the digital cadastral region to the world geodetic system, the boundary point coordinates must be changed to the legal coordinate units. However, there is a phenomenon that occurs in which the minute area changes do not coincide with the area registered in the cadastral registration when the coordinate unit is changed. In this study, we have developed a method to adjust many parcels collectively by applying a passive fine-tuning method used in cadastral resurvey project to solve these problems. Total 1, total 2+1, interval 1, interval 2+1, etc. were classified based on the number of parcels that need to be considered for the range of adjustment and the area condition. The analysis of the experimental area (after developing SW for comparison of each method) showed that the total 2+1 method is suitable for the location accuracy and the interval 2+1 method is suitable for the temporal efficiency.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.2
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• pp.36-54
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• 2004

The disposition of public parks pursue proper distribution and hierarchy formations on the basis of the neighborhood units theory. However, problems like price of land has brought about a large gap between theories and real conditions. This paper examines the problems of the practical disposition and disposition standards of public parks to solve these contradictions with reference to examples in Japan metro-cities. Study results are as follows; 1) The existing disposition theories are based on the district-boundary of men’s acting and settling down. Therefore, the disposition standards of large-scale parks or special parks beyond the humane scale have not been explained exactly. 2) As city sizes have expanded, these large-scale parks have developed greatly, however, they are located out of urban areas on the ground of nature’s geographical features. As a result, many small parks developed in urban areas. This extreme phenomenon of location would break up proper distribution and hierarchy. 3) Large parks over 4 ha not only take an important role in forming greenbelts but their location is also mainly based on their natural geographical features so that they are absorbed into the network -structure of greenbelts. 4) It is suggested that in planning parks, location and size of large parks over 4 ha should be selected and decided in the relation not with parks but with greenbelts. Parks of 4 ha or below are properly disposed. Also, these parks take a great role in forming the district boundary for settling down. Accordingly, proper distribution and hierarchy formation needs to be based on established neighborhood as they were previously.