• Computers and Concrete
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• 제21권1호
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• pp.39-46
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• 2018

With the increase in industrialization and urbanization, growing demand has enhanced rate of new constructions and old demolitions. To avoid serious environmental impacts and hazards recycled concrete aggregates (RCA) is being adopted in all over the world. This paper investigates successive recycled coarse aggregates (SRCA) in which old concrete made with RCA in form of concrete cubes was used. The cubes were crushed to prepare new concrete using aggregates from crushing of old concrete, used as SRCA. The mechanical behavior of concrete was determined containing SRCA; the properties of SRCA were evaluated and then compared with natural aggregates (NA). Replacement of NA with SRCA in ratio upto 100% by weight was studied for workability, mechanical properties and microstructural analysis. It was observed that with the increase in replacement ratio workability and compressive strength decreased but in acceptable limits so SRCA can be used in low strength concretes rather than high strength concrete structures.

• 한국농공학회지
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• 제31권1호
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• pp.45-57
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• 1989

The hydrologic model FESHM was introduced and its applicability was investigated in an attempt to analyze the rainfall-runoff relationships of urban small watersheds and to hereafter predict the envi-ronmental changes. Basic data on rainfall, water level, geomorphological characterisitics and land use were obtained from Yeonwha stream watershed located in Chonju-si Dukjin-dong. WL-5 for simulation o subshed WS# 1(136.7 ha) with urban district and WL-1 for total watershed WS#5 (278.78 ha) we'e selected as gaging points. The main results gained through applications were summarized as follows. 1. Direct runoff ratio caalculated from a simple separation method for WS#5 WS# 1 was 2O~39%, 38~62%, respectively. 2. Simulations for the runoff estimation were carried out for each watershed using 5 rainfall events, the simulation errors had the range of 2~ 30%, O~ 63% and O 120 minutes for the runoff volume, peak flow and peak time, respectively. 3. The effect of landuse change by urbanization was tested to WS# 1, runoff volume before development was estimated as from tenth to twentieth against after development.

• 가정과삶의질연구
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• 제10권2호
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• pp.87-97
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• 1992

The resulting rapid urbanization in Korea in several decades caused the problem of housing shortage and the various residential stressors. In spite of the seriousness of the problem. there have been very few studies that analyses systematically the effects of residential stressors on the housing adjustment attitudes and housing management behavior. The purpose of this study is to analyse such effects by identifying, on the basis of a comprehensive theoretical model. For this purpose, 822 housewives were sampled form the household in Seoul and Chonju-City. The main results obtained are as follows. 1) Higher tendency to housing adaptation tan housing adjustment attitudes. The lower level of stress is observed in housing adjustment than housing adaptation. 2) The higher level of housing management behavior is observed in the loser level of residential stress, the smaller level of living space, the higher level of family adaptation ability and social support.

• 한국조경학회지
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• 제21권2호
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• pp.17-33
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• 1993

This paper is the on-site case study of the shaping of townscape of port towns in Korea. Inchon has been experienced the rapid urbanization after the opening of a port. Inchon is selected because of the relatively rapid process, the apparent event and influence, and the enough referneces of data about the landscape formation and transformation. As the value of historical landscape, it is very significant to study Inchon and the causes of change in townscape depend on the external element-the opening of a port, Japan colonial policy, economic progress, nationwide development. The main purpose of this study is scrutinized the process, the cause and effect, and the contents and the form of shaping of townscape. The result of the interpretation of landscape is never perfect but only a starting point. Finally this study will be applied to the pragmatic task as a basic tool which construct the desirable image of the city.

• 한국환경과학회지
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• 제23권11호
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• pp.1851-1862
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• 2014

It is well known that urban relative humidity has continuous decreasing trend owing to the influence of urbanization. The change of relative humidity is directly influenced by two factors, namely, temperature effect and water vapor effect in various urban effects. In this study, the temperature and the water vapor effects on the relative humidity change were analyzed by using monthly mean relative humidities for a long period(1961~2013) in Busan and Daegu. The major results obtained in this study can be summarized as follows. Firstly, the urban dryness was caused mainly by water vapor effect in summer. But, for the other seasons, the urban dryness is mainly due to the temperature effect. Secondly, the relative humidity in Busan is on the decrease until now. This phenomenon is similar to another Korean huge cities such as Seoul, Daejeon and Incheon.

• 경영과정보연구
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• 제12권
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• pp.203-226
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• 2003

These days the surroundings around harbours are rapidly changing. Particularly in the age of Pacific Rim it is rather clear that the competition among the harbours in Northeast Asia region where are so many of worldwidely famous harbours might be intense. From 1980s on the industrialization and urbanization in the area of Kwang Yand-Bay, thanks to the regional development program, have been speedily under way. And in the year of 1987 the 1st development program of Kwang Yang-Bay container quay was started and is scheduled to be completed by the end of 1997. As the completion of the program it is expected that in 1998 the newly-opening Kwang Yang-Bay container quay on one hand will play a role in relieving the awaiting-time of vessels in Pusan Port, and on the other hand it will contribute to the balanced development of the country. In this context this thesis conducted Its study on the effect of the specification and facilities of a harbour, and especially on the effect on the regional economy resulted by the development & developmental static of Kwang Yang-Bay container quay. And progressively in the thesis the plan to provide Kwang Yang-Bay container quay with competitiveness was suggested.

• 산경연구논집
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• 제8권7호
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• pp.13-20
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• 2017

Purpose - Performance appraisal has a significant influence on the development of low-carbon tourism distribution. Research design, data, and methodology - Data of this study are collected from 27 provinces (cities) of China. SBM-Malmquist model is used to measure the TFP and its dynamic changes of low-carbon tourism distribution; TOBIT model is used to discuss the factors of TFP of low-carbon tourism distribution. Results - The results show that, there are obvious differences among regional TFP of low-carbon tourism distribution, the average change tends to grow positively in general, and the western region grows fastest on average due to the improvement of technical efficiency and technical progress, while there are technical efficiency improvement but technical regresses in eastern and central regions. The economic scale, economic strength, structure of energy consumption, location quotient and government regulation have a significant positive effect on the TFP of low-carbon tourism; energy intensity, industrial structure and opening degree have a negative effect; investments in fixed assets, intensity of R&D fund and urbanization rate have no significant influence on the TFP of low-carbon tourism. Conclusions - Improving the productivity of low-carbon tourism and reducing regional differences are effective ways to develop low-carbon tourism and enhance tourism competitiveness.

• 한국환경과학회지
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• 제17권3호
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• pp.297-303
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• 2008

For last couple of years many apartments, roads and bridges are constructed along the Kok-kyo stream which is penetrating Asan city, Chung-Nam Province. The effect of construction on stream environment was investigated in this study. Various kinds of water qualities of the Kok-kyo stream were monitored for 5 months. As it passed through the construction sites, $COD_{cr}$ concentration increased abruptly whereas the increment of the $BOD_5$ was not so great, indicating that non-biodegradable organics were flowed from the construction sites to the stream. Particularly, 0.2 mg/L of N-hexane was measured, which is believed to be mainly responsible for the organic pollution from construction sites. In spite of short periods of water quality monitoring, it could be concluded that there was a good correlation between construction sites and stream pollution. Therefore, legislative activity or enforced management by local government to the construction sites are needed for keeping the small stream environment better.

• 한국인구학
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• 제9권1호
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• pp.32-40
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• 1986

The purpose of the paper is to examine the nature of population distribution during the past 25 years; to evaluate effect of population redistribution policies which have been adopted by the government; and to suggest desirable future policy directions. The distinctive features of population distribution during the period of 196O~85 can be summarized as progress of rapid urbanization, decrease of absolute number of rural population and heavy concentration of population in the Seoul metropolitan area which have resulted in population maldistribution among regions. The problem of population concentration in the selected one or two large urban centers was first recognized by the government as early as in 1964. Since then numerous policy measures have been adopted to reduce the population concentration into the Seoul metropolitan area and thus to guide a sound population redistribution among regions. The overall assessment of various policies on population redistribution, however, revealed that the effect of the policy efforts has not been great as they originally anticipated. Various reasons can be cited for the failure of the past policies. Among them the followings were frequently mentioned; lack of integration among policy measures; weak linkage between relocation and accommodation; and non-existence of single authority for overall implementation of the polices. Based on the past experiences the followings are suggested in pursuing future policies. First, the short-term objective or target should be clearly defined. Second, policy measures have to be designed to go with rather than against market forces. Third, indirect incentives or aids are more effective than direct controls or regulations. Fourth, local participation has to be secured in every phase of policy formulation and implementation.

• Geomechanics and Engineering
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• 제28권6호
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• pp.559-571
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• 2022

Deep soil mixing, DSM technique has been widely used to improve the engineering properties of problematic soils. Due to growing urbanization and the industrial developments, disposal of brick dust poses a big problem and causes environmental problems. This study aims to use brick dust in DSM application in order to minimize the waste in brick industry and to evaluate its effect on the improvement of the geotechnical properties. Three different percentages of cement content: (10, 15 and 20%) were used in the formation of soil-cement mixture. Unlike the other studies in the literature, various percentages of waste brick dust: (10, 20 and 30%) were used as partial replacement of cement in soil-cement mixture. The results indicated that addition of waste brick dust into soil-cement mixture had positive effect on the inherent strength and stiffness of loose sand. Cement replaced by 20% of brick dust gave the best results and reduced the final setting time of cement and resulted in an increase in unconfined compressive strength, modulus of elasticity and resilient modulus of sand mixed with cement and brick dust. The findings were also supported by the microscopic images of the specimens with different percentages of waste brick dust and it was observed that waste brick dust caused an increase in the interlocking between the particles and resulted in an increase in soil strength. Using waste brick dust as a replacement material seems to be promising for improving the geotechnical properties of loose sand.