• Journal of the Korean Geotechnical Society
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• v.22 no.9
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• pp.5-14
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• 2006

Generally, the sediments contain significant water, clay, colloidal fraction and contaminants, and can result in soft strata with high initial void, and its potential hazards in subsurface environments exist. Electrokinetic technique has been used in sedimentation for volume reduction of slurry tailing wastes and in remediation for extraction of contaminants from contaminated soils. In this research, the coupled effects of sedimentation and remediation of contaminated sediments are focused using electrokinetic sedimentation and remediation techniques from experimental aspects. A series of laboratory experiments including variable conditions such as initial solid content of the specimen, concentration level of the contaminant, and magnitude of applied voltage are performed with the contaminated sediment specimens mixed with ethylene glycol. Commercially available high specification Kaolin was used to simulate slurried sediment. From the test results, the settlement of specimen increases with increasing of applied voltage and decreasing of solid content and contamination level. The density of specimen increases due to settlement of specimen in the process of electrokinetic sedimentation and decreases due to extraction of organic contaminant in the process of electrokinetic remediation.

• Korean Journal of Remote Sensing
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• v.39 no.5_4
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• pp.1145-1153
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• 2023

Urban trees play an important role in absorbing carbon dioxide from the atmosphere, improving air quality, mitigating the urban heat island effect, and providing ecosystem services. To effectively manage and conserve urban trees, accurate spatial information on their location, condition, species, and population is needed. In this study, we propose an algorithm that uses a high-resolution urban tree cover map constructed from deep learning approach to separate trees from the urban land surface and accurately detect tree locations through local maximum filtering. Instead of using a uniform filter size, we improved the tree detection performance by selecting the appropriate filter size according to the tree height in consideration of various urban growth environments. The research output, the location and height of individual trees in human settlement over Suwon, will serve as a basis for sustainable management of urban ecosystems and carbon reduction measures.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.2
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• pp.69-79
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• 1999

This study identifies the features of landscape elements on the fifteen districts with the idea of land use area and visual quantity of pictures by analyzing the air photo. Therefore, the sensibility of observer is comprehended through simulating the landscape evaluation and the landscape preference with using slide film. The study is divided into three periods to understand the transition of rural landscape as the social and cultural environments have been changed. The first period is the New Community Movement which affected the rapid change of social and cultural environments. The second and third periods are the prior and post time at the rearrangement of administration district in the Tae-Jeon Broad City. The result of this study is explained below part; 1. The transition of rural landscape has been occurred as the land use pattern has been altered. The change of pattern has affected an increase of the natural space and the structure change of agricultural productive space. 2. In the regression analysis, the regression model of landscape preference and land use ratio show; Landscape preference = 3.632 - 11.618 (Residential Area) - 4.227 (Equipped Farm). The explanation variables defined as Residential Area and Equipped Farm, and the relationship of those factors shows negative. Therefore, the increase of other building will make the rural landscape lower and worse.

• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.21-32
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• 2020

As the global large-scale infrastructure construction market expands, the construction of civil engineering structures in extreme environments such as cold or hot regions is being planned or constructed. Accordingly, the construction of the pile foundation is essential to secure the bearing capacity of the upper structure, but there is a concern about loss of stability and function of the pile foundation due to the possibility of ground deformation in extreme cold and hot regions. Therefore, in this study, a new type of pile foundation is developed to respond with the deformation of the ground, and the ground deformation that can occur in extreme cold and hot region is largely divided into heaving and settlement. The new type of pile foundation is a form in which a cylinder capable of shrinkage and expansion is inserted inside the steel pipe pile, and the effect of the cylinder during the heaving and settlement process was analyzed numerically. As a result of the numerical analysis, the ground heaving caused excessive tensile stress of the pile, and the expansion condition of the cylinder shared the tensile stress acting on the pile and reduced the axial stress acting on the pile. Ground settlement increased the compressive stress of the pile due to the occurrence of negative skin friction. The cylinder must be positioned below the neutral point and behave in shrinkage for optimum efficiency. However, the amount and location of shrinkage and expansion of cylinder must comply with the allowable displacement range of the upper structure. It is judged that the design needs to be considered.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.309-312
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• 2002

This paper reviews depositional environments, consolidation characteristic of marine deposits along the Nam-Yang river mouth and then analytical solution of self-weight consolidation is made to find consolidated state. This area has been deposited through the short geological age(22year). It's deposition rate is as high as 70cm/year and the height of deposition may be $3{\sim}12m$. It's known that this area is in the under-consolidated state from OCR and analytical solution. It is conclude that the under-consolidated state should be considered in prediction of consolidation settlement.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.151-154
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• 2003

This paper reviews depositional environments and consolidation characteristic of Soft Dredged Clay fill and then analytical solution of self-weight consolidation is made to find consolidated state. It's known that Soft Dredged Clay Ground is in the under-consolidated state under $U{\fallingdotseq}30%$ from analytical solution. It is effective for higher consolidation rate that the time of Dredge is shorter ani the time of leave is longer. It is conclude that the under-consolidated state should be considered in prediction of consolidation settlement.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.339-340
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• 2018

Contemporary concrete structures make use of underground spaces as parking lots and other comfort facilities for efficiency purposes. As underground environmental conditions are in constant exposure to degradation factors from the environment such as groundwater, hydraulic and soil pressure, structural movement and settlement, structural defects in the form of leakage occur. Current maintenance regulations and regimes are unable to respond to this field, as degradation mechanisms in underground environments are still unclear. In this regard, this study proposes the utilization of integrated information sharing system that can provide various technical information for construction designs to prevent leakages in underground concrete structures.

• International Commerce and Information Review
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• v.8 no.1
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• pp.87-104
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• 2006

We are in an era of global business called one world market. These environments require Korean firms to face an unlimited competition and to resolve their dispute by ADR. Few study, however, on the ways of dispute settlement under the changed international business environment has been done. Thus the major purposes of this study are to investigate Busan's trading companies' preference on the dispute resolution ways. Based on the results of my study, I suggest Busan's trading companies the following guidelines. First, Busan's trading companies should improve their negotiating power by using internet trade and problem solving ability through the establishment of claim information system. Second, They should write contract. Lastly, they should investigate their counterparty's credit.

• Journal of Ecology and Environment
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• v.35 no.1
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• pp.27-34
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• 2012

Typha angustifolia has ecological characteristics of clonal growth similar to Phragmites australis. The plant spreads byclonal growth and seed dispersal. In this study, for the three stands which have different settlement age at the Baksilji wetland in Korea, genetic diversity was estimated by random amplification of polymorphic DNA analysis to evaluate the change in genetic diversity of T. angustifolia during stand development in the same population. Stand (ST) 1 was the oldest and ST 4 was the youngest. ST 5 was in a small ditch out of the Baksilji. Although the ST 1, ST 2, and ST 3 did not differ significantly in vegetational or physical environment, the genetic diversity estimated according to Nei's gene diversity (h) and the Shannon index (i) increased in the order of ST 1 < ST 2 < ST 3 contrary to formative age. The genetic diversity of ST 4 was much higher than that of the other three stands. ST 4 has similar abiotic environmental conditions with slight T. angustifolia dominance, and seems to be in the early establishment stage. ST 5 differed from the other stands in vegetational and soil environments, which can result in stressful cattail conditions. Even though the ST 5 stand was not younger than the ST 4 stand, ST 5 showed the highest genetic diversity. Our results indicate that after early settlement of the T. angustifolia population, genetic diversity within the species decreased over time and that the decreasing pattern of genetic diversity within T. angustifolia stands is not likely to occur under stressful conditions.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.638-641
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• 2003

This paper suggests that construction management services should be performed considering the owner's and the project's characteristics through the examples of the successful projects. For this study, the critical CM services in each phase regarding schedule management, cost management and information management are presented and the problems of the CM delivery system in Korea are analyzed with respect to policies, users, suppliers/CMrs and construction environments. Besides, the situation of the delivery systems in Korea and the differences of each delivery system are presented. It is concluded that, for the settlement of CM delivery system in public construction market and, ultimately, the successful execution as an agent of the owner, CMr should diversify the services and give the optimum CM services appropriate for each project's characteristics.