• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.39-50
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• 2015

This research selected Daegu Metropolitan City representing a combination of natural space and urban space for this case study. To achieve this, a prerequisite was to set up an optimal block size to evaluate landscape diversity of the research site by using a RPR-Area Curve. Further, landscape diversity evaluation was conducted based on land cover map by using FRAGSTATS to analyze spatio-temporal changes. Notably, this research regarded it as the most significant to set forth criteria in order to apply landscape diversity to the development plans of the newtown and outskirt of a city under high pressure development. Results derived from this research are summarized as follows. According to the results derived from establishing the optimal block size, a size about $2km^2$ was analyzed to measure landscape diversity of the research site. Also, according to the results derived from land diversity evaluation based on land cover map, land diversity was highly measured around urban stream such as Nakdong River and Geumho River, and in particular, the value of landscape diversity was measured considerably high around the urban parks. Results derived from analysis on spatio-temporal changes of land diversity demonstrated that a certain level of urban development exerted a positive effect on an increase in land diversity, but consistent urban development lowered a value of landscape diversity. Results derived from regression analysis to set forth the optimal urban space showed that an urban area of a space about $2km^2$ exerted a positive effect at a rate of about 0~43.3% and a negative effect at a rate about 43.3~100%. In conclusion, the results of this research are considered to provide important basic data for future urban and landscape planning. Nonetheless, as only the layout on the 2D plane was analyzed in this research, further research in future is required to complexly consider diverse factors such as height of structure and change in visible real area arising from geographical features.

• Journal of the Korean Geotechnical Society
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• v.31 no.1
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• pp.53-64
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• 2015

This study presents the experimental results of pervious blocks subjected to a series of unique inflow conditions in urban area. The measured properties include the strength, permeability, drainage capacity and runoff, and evaporation for blocks made of two different size of aggregates. Results revealed that the strength satisfies the Korean Standard regardless of aggregate size whereas the immediate runoff occurred for the block with small size aggregate. On the other hand, the block with large aggregates allowed the drainage upon the initial inflow condition, which became hampered to induce the runoff by subsequent inflow. It was attributed to the fact that the capillary water often served as the hydraulic barrier in partially saturated condition. The salient observation indicated that the runoff highly depended on the evaporation and pre-wetting condition as well as the porosity and pore connectivity. The bilinear evaporate rate that makes the degree of saturation vary also had great influence on deterining the time-dependent runoff.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.3
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• pp.91-104
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• 2020

This study was conducted to analyze the characteristics of defects according to the type of block and spatial type by quantitatively examining defects occurring in block pavement in apartment complex. According to the research results, depending on the type of block, defects have occurred 1,394.3ea/100㎡ in interlocking paver blocks, 464.8ea/100㎡ in clay brick paver blocks, and 235.1ea/100㎡ in shot blasted paver blocks. By space type, the defects were occurred 1,576.0ea/100㎡ on the access road paved by interlocking paver blocks and the defects were found 1,139.6ea/100㎡ in interlocking paver blocks, 235.1ea/100㎡ in shot blasted paver blocks, and 797.1ea/100㎡ in clay brick paver blocks, on the sidewalk. Also the defects are occurred 455.6ea/100㎡ on the resting space and 403.2ea/100㎡ on the gym space paved by clay brick paver blocks. Through the size analysis of the defects in the block paver, in the case 'peeling', the largest volume of 2,539.0㎣ on the sidewalk paved with shot blasted paver blocks, and 'Subsidence' occurred at the widest area of 2,096.0㎠ on the sidewalk where interlocking paver block was constructed. The difference in defect occurrence according to the type of block is considered to be influenced by the block production process, and the space type is considered to be caused the difference in the occurrence of defects according to the cause of construction and the usage pattern of residents. This study conducted a survey on defects in block and analyzed the defect characteristic according to paver material and space type. Base on this, it is judged that it can be used as an efficient basic data for material replacement, improvement, paver planning and construction in the future.

• Journal of the Korean housing association
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• v.18 no.3
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• pp.125-136
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• 2007

To improve the environment of individual residential area, the uniform development of multiple dwellings through site should be avoided. As an alternative to a large scale development of the currently popular high-density and high-rise apartment buildings, which disintegrates and destroys existing communities, a new residential type that is applicable to the individual residential area should be developed. From the new residential type, even for short history of Korea of modem urban residence, a new concept of residence can be formed, changing from the concept of a temporary staying place to the concept of a stable residing place. Also, a gradual improvement that transcends time can be expected, and the present and past appearances can co-exist. This study was conducted to suggest a new residential type with unit blocks that can improve the physical structure of existing individual residential area without destroying the structure. That is, among the factors that comprise the individual residential area, this study will focus on the unit block with a medium role between a site and a mega-block, and will suggest a new concept of residential unit in order not to destroy its physical structure. The physical characteristics of the unit block will also be analyzed.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.157-166
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• 2012

Most of the roads are paved with impermeable materials such as asphalt concrete and cement concrete, and in the event of heavy rainfall, rainwater directly flows into river through a drainage hole on the pavement surface. This large quantity of rainwater directly spilled into the river frequently leads to the flooding of urban streams, damaging lowlands and the lower reaches of a river. In recent years there has been a great deal of ongoing research concerning water permeability and drainage in pavements. Accordingly, in this research, a porous polymer concrete was developed for permeable pavement by using unsaturated polyester resin as a binder, recycled aggregate as coarse aggregate, fly ash and blast furnace slag as filler, and its physical and mechanical properties were investigated. Also, 3 types of permeable polymer block by optimum mix design were developed and rainfall runoff reduction effects by permeability pavement using permeable polymer block were analyzed based on hydraulic experimental model. The infiltration volume, infiltration ratio, runoff initial time and runoff volume in permeability pavement with permeable polymer block of $300{\times}300{\times}80$ mm were evaluated for 50, 100 and 200mm/hr rainfall intensity.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.2
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• pp.47-57
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• 2023

The increase of impermeable area ratio is causing hydrologic cycle problems in urban areas and groundwater depletion in rural areas, permeable pavements are getting attention to expand permeable areas. The performance of the permeable concrete block pavement, which is part of the permeable pavement, is greatly affected by the porosity. In addition, the permeability coefficient is a major factor when designing permeable concrete block pavement. Existing porosity and permeability test methods have problems such as uneconomical or poor field applicability. The object of this study was to develop a methodology for evaluating porosity and permeability coefficient using a surface image of a permeable concrete block. Specimens are manufactured with various porosity ranges and porosity and permeability tests are performed. After surface image preprocessing, normalization and binarization methods were compared. Through this, the method with the highest correlation with the lab test result was determined. From the results, the PDR (pore determined ratio) was obtained. Simple linear regression analysis is performed with PDR and lab test results. The results showed a high correlation of R² more than 0.8, and the errors were also low.

• Journal of the Korean Association of Geographic Information Studies
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• v.2 no.2
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• pp.27-44
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• 1999

Digital maps produced in Korea are various in scale and include a lot of geographic and attribute data. In this study, it is argued that, to reduce the production cost and the difficulties for renewal, it is necessary to establish the already nationally drawn 1:5,000 scale digital maps as the base maps and simplify them as much as the TIGER files in the U.S. The comprehensive data included in the digital maps in Korea are mostly land use information, which are supposed to be established separately from the digital maps. The land use information system could be maintained and updated cheaply and frequently at the local government level. In response to common needs, the land use information could be imported to GIS and used for analyses. As technologies and societies changes, the Census questions and methodologies should be changed for better uses. Along with GIS, the Census would be developed and processed more reliably and efficiently. Also, it is recommended for Korean government to develop the Census Tract and Block Group system. Current Eup, Myon, Dong as basic units for Census information may not be useful or effective for micro level urban analyses and public service planning activities because of their large population and land areas. It is recommended that optimum population of a Census Tract be 5,000 and a Block Groups 1,500, and one Census Tract includes 1~9 Block Groups. It is recommend that Census Tract and Block Group boundary lines be decided flexibly in light of population, physical features, socio-economic attributes, and tradition. For urban analyses using GIS, socio-economic census data, city government's information such as parcel data and building permit data, survey data, and satellite image data could also be used. The existence of Census Tracts and Block Groups as well as GIS could help for the data and methods to be useful for urban analyses and public service provisions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.723-730
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• 2006

Recently, The flexible moving block system in train operation has been introduced to the worldwide rail transportation markets. This paper is a comparative study of the conventional fixed block systems effects and the flexible moving block system on train operating time saving. Based on the literature review, the new algorithm is developed. It is to calculate the optimum headway time of the train. The proposed algorithm can overcome some of the existing algorithm problems, such as the limits of the data and unaware of the rail characteristic. The total travel time saving effect has been analyzed by applying the skip stop scheduling system to the each block system. The results of this study indicated that the total travel time is approximately 40% decreased and the schedule velocity is approximately 24% improved when the moving block system is applied. The results of this study could be used as a theoretical basis for the selection of rail signal system in Seoul's subway number 2 line.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.551-563
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• 2019

This study examined the characteristics of a district through the concept of a block system in the physical aspect of the four land readjustment project districts of Cheongju City in the 1970s. The results of this study are as follows. First, the local road system for accessing the main road network and blocks was well established compared with the current urban development standards. On the other hand, since the access roads to the individual lots in the block were not equipped properly, it was difficult to improve a house. Second, according to the characteristics of the block, the Aspect Ratio of blocks was 1: 2 on average and most of those directions was east-west. The area of block from the 1st to 3rd districts was increasing, but districts 4 were decreasing. This also was changed to the shape of a contemporary block system. The larger the size of the block area, the lower the Jeobdoyul. Third, in terms of the characteristics of the lot array, blocks with a multi-row system of $4{\times}4$ or more were lots up to the 1st to 3rd district, but 4th district was improved greatly. Because blocks close a square shape have become excessively poor with Jeobdoyul, it was judged that it is difficult to improve the residential environment. Moreover, as the type of the residential development by the land readjustment project is standardized considerably and this type of land area is extensive, it can be an alternative to control the urban sprawl of suburbs if it finds the way to improve this type of the residential area considering this characteristic.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.168-169
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• 2019

Recently, the flooding of rivers caused by rainy season and heavy rains in Korea causes economic and environmental problems such as flood damage and urban flooding. Therefore, in order to solve these problems, local governments use landscaping methods and drainage facilities to prevent them, but they are not perfect solutions. Domestic awareness also lacks awareness to worry about flooding only during rainy seasons and heavy rains, and to worry about or prevent flooding in the region. In order to solve this problem, we recognize the importance of permeable blocks nationwide and replace or install permeable paving materials on most sidewalks. However, since existing permeable blocks used cement as the main material, calcium carbonate is produced when reacted with water. Efflorescence occurs, and the resulting calcium carbonate blocks the pores of the permeation block, causing a decrease in permeability.