• Journal of Korean Association for Spatial Structures
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• v.24 no.3
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• pp.61-68
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• 2024

High-rise buildings are equipped with TMD (Tuned Mass Damper), a vibration control device that ensure the stability and usability of the building. In this study, the seismic response control performance was evaluated by selecting the design variables of the TMD based on the installation location of the twisted irregular building. To this end, we selected analysis models of 60, 80, and 100 floors with a twist angle of 1 degree per floor, and performed time history analysis by applying historical seismic loads and resonant harmonic loads. The total mass ratio of TMDs was set to 1.0%, and the distributed installation locations of TMDs were selected through mode analysis. The analysis results showed that the top-floor displacement responses of all analysis models increased, but the maximum story drift ratio decreased. In order to secure the seismic response control performance by distributed installation of TMDs in twisted irregular buildings, it is judged that the mass ratio distribution of TMDs will act as a key variable.

• Journal of the Korean Regional Science Association
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• v.6 no.2
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• pp.149-153
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• 1990

• Spatial Information Research
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• v.17 no.2
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• pp.231-241
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• 2009

Recently, The importance of a quality control for implementing 3D geospatial database has being emphasized to build a 21st century knowledge society and an ubiquitous land. The improvement of 3D geospatial database quality control through establishing an integrated quality control makes data suppliers update data efficiently and users get high quality data. The purpose of this study was to derive the improvement plan of 3D geospatial database quality control through the analyses of the existing 3D geospatial database quality control and case studies. The results of this study are as follows. Firstly, we defined the concept of 3D geospatial database quality control. Secondly, we set the boundary, factors and process of 3D geospatial database quality control through classifying it in detail. Lastly, we drew improvement contents such as the quality control checklist by implementation process according to the improvement plan of 3D geospatial database implementation.

• Journal of Korean Association for Spatial Structures
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• v.22 no.3
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• pp.49-56
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• 2022

Tuned mass damper (TMD) is widely used to reduce dynamic responses of structures subjected to earthquake loads. A smart tuned mass damper (STMD) was proposed to increase control performance of a traditional passive TMD. A lot of research was conducted to investigate the control performance of a STMD based on analytical method. Experimental study of evaluation of control performance of a STMD was not widely conducted to date. Therefore, seismic response reduction capacity of a STMD was experimentally investigated in this study. For this purpose, a STMD was manufactured using an MR (magnetorheological) damper. A simple structure presenting dynamic characteristics of spacial roof structure was made as a test structure. A STMD was made to control vertical responses of the test structure. Two artificial ground motions and a resonance harmonic load were selected as experimental seismic excitations. Shaking table test was conducted to evaluate control performance of a STMD. Control algorithms are one of main factors affect control performance of a STMD. In this study, a groundhook algorithm that is a traditional semi-active control algorithm was selected. And fuzzy logic controller (FLC) was used to control a STMD. The FLC was optimized by multi-objective genetic algorithm. The experimental results presented that the TMD can effectively reduce seismic responses of the example structures subjected to various excitations. It was also experimentally shown that the STMD can more effectively reduce seismic responses of the example structures conpared to the passive TMD.

• Korean Journal of Remote Sensing
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• v.36 no.5_1
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• pp.707-723
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• 2020

In this study, a decision tree type of quality control (QC) method was developed to improve the temporal-spatial representation and accuracy of the visibility data being operated by the Korea Meteorological Administration (KMA). The quality of the developed QC method was evaluated through the application to the 3 years (2016.03-2019.02) of 290 stations visibility data. For qualitative and quantitative verification of the developed QC method, visibility and naked-eye data provided by the KMA and QC method of the Norwegian Meteorological Institute (NMI) were used. Firstly, if the sum of missing and abnormal data exceeds 10% of the total data, the corresponding point was removed. In the 2nd step, a temporal continuity test was performed under the assumption that the visibility changes continuously in time. In this process, the threshold was dynamically set considering the different temporal variability depending on the visibility. In the 3rd step, the spatial continuity test was performed under the assumption of spatial continuity for visibility. Finally, the 10-minute visibility data was calculated using weighted average method, considering that the accuracy of the visibility meter was inversely proportional to the visibility. As results, about 10% of the data were removed in the first step due to the large temporal-spatial variability of visibility. In addition, because the spatial variability was significant, especially around the fog area, the 3rd step was not applied. Through the quantitative verification results, it suggested that the QC method developed in this study can be used as a QC tool for visibility data.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.291-297
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• 2019

Since Metcalfa pruinosa was first reported in Koera, it has continually caused damage to sweet persimmon orchard in southern part of Korea. Metcafa pruinosa exist not only in farmland but also in forest areas, and are difficult to control due to the influx of individuals from near forest. M. pruinosa has been occurred in orchard and its surroundings because of various host range. Thus, it has been difficult to decide spatial range and control time for efficient management. In this study, occurrence and dispersal pattern of M. pruinosa in persimmon orchard were surveyed using clear sticky traps, and spatial patterns were analyzed with SADIE(Spatial Analysis by Distance IndicEs), based on location information at sticky traps. Spatial association between survey time was also analyzed to identify when the spatial pattern changed. In sweet persimmon orchard, M. pruinosa mainly dispersed in mid to late May, when the first instar hatches, and in August, emerging season of adult. The first instar nymphs hatched in mid-May were randomly distributed in orchard, but distribution was changed to aggregative pattern after dispersed surroundings of orchard. Adults showed random distribution pattern after immigration to orchard again. These tendency was also observed in density change at orchard and its surroundings, and matched to actual density of M. pruinosa in sweet persimmon trees.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.305-315
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• 2020

The purpose of this study is to compare algorithms of single photo resection, which determines the exterior orientation parameters used in fields such as photogrammetry, computer vision, robotics, etc. To this end, the algorithms were compared by generating experimental data by simulating terrain based on a camera used in aerial and close-range photogrammetry. Through experiments on aerial photographic camera that was taken almost vertically, it was possible to determine the exterior orientation parameters using three ground control points, but the Procrustes algorithm was sensitive to the configuration of the ground control points. Even in experiments with a close-range amateur camera where the attitude angles of the camera change significantly, the algorithm was sensitive to the configuration of the ground control points, and the other algorithms required at least six ground control points. Through experiments with two types of cameras, it was found that cosine lawbased spatial resection shows performance similar to that of a traditional photogrammetry algorithm because the number of iterations is short and no explicit initial values are required.

• Journal of the Korean housing association
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• v.18 no.3
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• pp.81-89
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• 2007

This study is aimed at understanding objectively on the visual perception of atypical space and form in contemporary architecture. It is accomplished to compose the various form and the atypical space in contemporary architecture, which by means of applying digital technology to architecture is able to materialize complicated form and space. Therefore this the sis is needed to understand user's senses and affects in atypical space and form. Atypical space is able to interpret geometrically and analyze quantitatively into visual perception. This analysis is applied to Isovist used as quantitative analysis recently, and physical analysis of space used as quantitative analysis defined to vertical elements, which is analysed comparatively to visual perception in observer's point and characteristics in spatial elements. Examples are selected to four examples represented to typical and atypical space in contemporary houses. As examples are analysed to visual perception of spatial character, this study is intended to understand to spatial character in aspects of spatial composition and observer's visual perception. In results of perceptive analysis on four spatial examples, Atypical spaces are composed of changeable spatiality, which are composed changeably of the relational method with adjacent spaces. Also, typical spaces are composed monotonously of spatiality and relational method on control of the length in boundary plane and openness.

• Journal of the Korean Institute of Rural Architecture
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• v.15 no.1
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• pp.89-96
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• 2013

This study aims to clarify the transformation of urban spatial structure around old castle in cheong-ju city. The urban spatial structure is composed with road system, block division, and lot system with original cadastral map in 1913 and 2011 GIS. Transformation of road system is classified into control of road line, construction and extension of road. Construction of arterial road was divided into Nam-juro and Mang-sunro with 2 blocks and lot system was destoyed. Transformation of block has not been developed except 4 blocks. The 4 blocks were divided into east-west or north-south direction and became 8 blocks. Transformation of lot system is classified into maintained, subdivided, and destroyed lots in shape and size of lots. Maintained lots were found in large lot in size for public office and park. Subdivided lots were mainly represented with the existing main road, an active alleys, and so on. Destroyed lots by road construction and extension were showed in Nam-juro. Although all these transformations are used to enhance urban spatial structure. The old systems have remained around old castle in cheong-ju city.

• Journal of Korea Spatial Information System Society
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• v.8 no.1 s.16
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• pp.59-75
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• 2006

One of the most challenging and encouraging applications of state-of-the-art technology is the field of traffic control systems. It combines techniques from the areas of telecommunications and computer science to establish traffic information and various assistance services. The support of the system requires a moving objects database system (MODB) that stores moving objects efficiently and performs spatial or temporal queries with time conditions. In this paper, we propose schemes to distribute an index nodes of trajectory based on spatio-temporal proximity and the characteristics of moving objects. The scheme predicts the extendible MBB of nodes of index through the prediction of moving object, and creates a parallel trajectory index. The experimental evaluation shows that the proposed schemes give us the performance improvement by 15%. This result makes an improvement of performance by 50% per one disk.