• Water for future
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• v.22 no.1
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• pp.81-90
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• 1989

A numerical simulation technique of three-dimensional finite difference model is developed to study the groundwater flow system in Dejima, an upland area which faces Kasumigaura Lake. For general perspectives of the groundwater flow system, a steady state three-dimensinal model is simulated. For the sedimentary mud formations which are found in the representative formation, three situations where the horizontal permeability is equal to 10 times and 100 times of the vertical one. The finite difference grid used in the simulation has 60$\times$50$\times$30=90,000 nodes. A converged solution with a tolerance of 0.001 meter of hydraulic head is set. Having determined the flow net by using a steady state three-dimensional model, the results for the three cases of hydraulic conductivity are compared with the results of the tracer methods (Bae and Kayane, 1987). With the aid of four representative vertical cross-sections, groundwater flow systems in the study area are assumed. The results of these are reasonally good comparable with the results of the basin yield and thd recharge-discharge distribution 8.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.6
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• pp.68-74
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• 2011

The touch or step voltages which exist in the vicinity of a grounding electrode are closely related to the earth structure and resistivity and the ground current. The grounding design approach is required to determine the grounding electrode location where the hazardous voltages are minimized. In this paper, in order to propose a method of mitigating the electric shock hazards caused by the ground surface potential rise in the vicinity of a counterpoise, the hazards relevant to touch voltage were evaluated as a function of the soil resistivity ratio $\rho_2/\rho_1$ for several practical values of two-layer earth structures. The touch voltage and current on the ground surface just above the test electrode are calculated with CDEGS program. As a consequence, it was found that burying a grounding electrode in the soil with low resistivity is effective to reduce the electric shock hazards. In the case that the bottom layer soil where a counterpoise is buried has lower resistivity than the upper layer soil, when the upper layer soil resistivity is increased, the surface potential is slightly raised, but the current through the human body is reduced with increasing the upper layer soil resistivity because of the greater contact resistance between the earth surface and the feet. The electric shock hazard in the vicinity of grounding electrodes is closely related to soil structure and resistivity and are reduced with increasing the ration of the upper layer resistivity to the bottom layer resistivity in two-layer soil.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.5
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• pp.62-69
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• 2010

This paper presents the dependances of transient grounding impedances of counterpoises on the soil structures and the injected point of impulse currents. The transient and conventional grounding impedances of the 25 and 50[m] counterpoises buried in the soil with different resistivity were measured and analyzed as a function of the rise time of impulse currents. As a result, the transient grounding impedances give an inductive behavior, and the trend of the conventional grounding impedances is similar to that of the transient grounding impedances. The ground resistance of counterpoises is irrespective to the injected of impulse current, but the transient and conventional grounding impedances in a short time range especially depend on the soil resistivity and position of the injected point of impulse currents.

• 지역과문화
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• v.6 no.1
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• pp.57-80
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• 2019

In this study, we will investigate Nujung culutre of Seobuk-jung in Hamra, which is representative Nujung in the modern period Iksan region, and examine how to use it as local contents. Hamra, where Seobyeog-jeong is located, was an economic center in the Joseon Dynasty. Under the historical and economic background, Seobyeong-jeong was erected by Lee, Chip-chon in 1926. The study of Seobyeong-jeong and Nujung culture erected by the Landloard family of Honam in modern times can be used as an important data for understanding the Nujung culture of modern Iksan Proviance.

• The Korean Journal of Quaternary Research
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• v.2 no.1
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• pp.25-50
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• 1988

The survival of rich evidence of palaeolithic occupation found in the Imjin-Hant'an River basin was possible due to many fortuitous geological conditions provided there. Formation of the basalt plain in a narrow valley system which developed during the late Mesozoic insured the appearance of a basin of sedimentation in which archaeological sites would be preserved with relatively minor post-depositional disturbance. Geomagnetic and K-Ar dating indicates that lava flows occurred during the Brunes Normal Epoch. During and after the process of basin sedimentation, erosion of the plain was confined to the major channel of the present river system which developed along the structural joints formed by the lava flow. Due to characteristic columnar structure and platy cleavage of the basalt bedrock, erosion of the basalt bedrock occurred mainly in vertical direction, developing deep but narrow entrenched valleys cut into the bedrock. Consequently, the large portion of the site area remained intact. Cultural deposits formed on top of the basalt plain were left unmodified by later fluvial disturbances due to changes in the Hant'an River base-level, since they were formed about 20 to 40m above the modern floodplain. Sedimentological evidence of cultural deposits and palynological analysis of lacustrine bed formed in the tributary basin of the Hant'an River indicate that hominid occupation occurred in this basin under rapidly deteriorating climatic conditions. From three thermoluminescence dates, the timing of hominid occupation as represented by 'Acheulian-like' bifaces apparently occur sometime during 45,000 BP. Thus, deposition of cultural layers in this basin approximately coincides with the beginning of the second stadial of the final glacial, during which the Korean Peninsula must have had provided a sanctuary for prolonged human occupation.

• Spatial Information Research
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• v.2 no.1
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• pp.85-92
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• 1994

This study examines the unique characteristics of the parcel identification number especially in developing the Korean land information system(KLIS). There are several limitations in establishing KLIS in terms of the location identification. Therefore, it is necessary to develop the appropriate parcel identification number system in Korea including the road identification systym and the three dimensional parcel identification system. The exact parcel bounary also needs accurate surveying and registration.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.153-154
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• 2011

최근 발생한 일본 동북부의 대지진과 이에 동반된 해일은 막대한 재산손실과 인명피해를 가져왔다. 일본에 인접한 우리나라도 규모 3~4의 지진이 빈번히 일어나고 있고, 그 이상의 규모 지진도 간혹 발생하고 있다. 따라서 더 이상 한국이 지진과 해일의 안전지대라고 안심할 수 없는 상황이다. 이에 본 논문은 지진과 함께 동반되는 해일에 대비하기 위한 경보 및 상황 보고 시스템의 필요성을 제시하고, 사용자들이 경보를 받을 뿐 아니라 스마트폰을 이용한 SNS와 GPS를 이용하여 실시간으로 상황 보고에 대한 의견 교환을 하면서 함께 대피하도록 돕는 실시간 경보 및 상황 보고 시스템을 제안한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.283-285
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• 2022

도시는 지속적으로 변화하고 있으나, 도시어항은 도시화에 비해 쇠퇴되고 있다. 도시어항 어민들의 어업활동은 축소되고 있으며, 어항의 새로운 변화와 활력이 필요한 실정이다. 그러나 어촌계의 고령화, 어항구역 및 인접 대지의 토지활용 등 실질적인 한계점은 어항의 발전을 저해하고 있으며, 본 연구에서는 이를 극복할 수 있는 대안으로서 암남항 해녀와 낚시 콘텐츠를 활용한 해양문화콘텐츠를 제시하고자 한다. 또한 2022년 암남항 어촌뉴딜300사업 시행에 앞서, 암남항의 해양문화콘텐츠를 개발하고 도시어항 공간환경마스터플랜을 수립함으로서 암남항의 새로운 발전을 도모할 수 있는 실질적인 연구 수행의 의의가 있다.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.04a
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• pp.477-484
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• 2000

Earthquake response analyses are conducted for the investigation of the ground shaking during the 1995 Hyogoken-nambu earthquake. Port Island a man made island with about 8{{{{ KAPPA m^2 }} area is chosen for this purpose Because earthquake measurement with vertical array was conducted there. Strain dependent characteristics of soil can be modeled well into Hardin-Drnevich Model. Four analyses are conducted : total stress analysis by equivalent linear method non-linear method. and two effective stress analyses. All analyses except equivalent linear analysis show fairy good agreement with observed record mainly because the non-linear behavior of Holocene clay layer has predominant effect on the behavior of fill, However detailed investigation show that effective stress analyses give much better prediction than total stress analyses.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.116-123
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• 2000

본 논문은 1995년 일본 남부 효고켄 남부 지진 (코베 대지진)에 의해 코베시에 위치하는 인공섬인 포트 아일랜등서 발생한 액상화 현상을 해석적 기법을 동원하여 액상화 현상의 저감 효과 혹은 방지를 위하여 실시되어져 오고 있는 여러 공법들의 타당성을 수치해석적인 입장에서 검증한 것이다. 따라서, 본 논문에서는 코베시에 의해 획득되어진 연직 방향의 지진 기록에 의해 포트 아일랜드 시공 당시 구역별로 다른 지반 개량 공법을 실시했고, 혹은 실시하지 않는 구역에 대해서 1차원 및 2차원 전응력 그리고 유효 응력 해석 기법을 동원하여 일련의 해석을 실시하였고 그 결과를 다각적인 방향에서 제시하였다.