• Journal of the Korean Geotechnical Society
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• v.27 no.1
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• pp.25-34
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• 2011

In general, many instrumentations of slope rely on theory or experience because on-site accessibility and long term instrumentation are difficult to conduct the instrumentation of slopes. Also the prediction of disaster is very difficult. Therefore experimental research was conducted about an effective method to predict collapse of slope and on-site applicability in this study. The collapse of slope was able to be predicted by applying AE sensor which we call WEAD to the failure criteria. The parameters of AE generated during the collapse of slope were secured through bending shear test. Test construction was applied to the slope with a history and a possibility of collapse. As a result, it is shown that AE parameters do not exceed the failure criterion and is found to be stable slopes. As the real symptoms of collapse did not appear, AE was found to have excellent applicability.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.6 no.1
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• pp.179-213
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• 1984

The history of recording and conserving for maintenance the human's memory from ancient times to modern's has brought about a lot of changing process of the recorded information media with developing in culture, and each society has made important recorded materials in his library as essentially the social apparatus. But most of them that were damaged by factors of the natural disaster, humidity, temperature, light, fungi and insects in the library, and were resulted in deterioration and losing the numerous materials. For removing the inevitable phases repeated, there are studying for counterplan of the fundamental environment factors about preservation, restoration and chemical research of materials in advanced countries, but I get a few researches about protecting the cultural properties. Therefore I research the survey of the actual conditions on 72 university libraries centering around them, and then I have researched the collection rate 81 percent, 58 university libraries. (local : 35, in seoul : 23) As the result of this research, I propose the model of the environment factors of conserving the library materials. 1) To apply the equipment of processing the radiant energy to the new construction and buildings. 2) To remove factors that occur fungi and insects by facilities being controlled relative humility, temperature, and to equip the ventilation arrangement in the library. 3) To shelve all acquired and bound materials after proceeding the vacuum fumigator. 4) Those who want to enter into the library stack were surely taken in sterilzing their hands and shoes, and must put on the gown. 5) To use the vacuum dusting thing (machine) for removing the dust without spreading out the floor of the library at any time. 6) To set up the gas automatic fire extinguisher worked by smoke sensor. 7) To assist the research into the preservation, natures and environment of recorded materials, and to supply financial funds for librarian. 8) To hold regularly the workshop be able to educate the methods of preservation materials by the constant system. (Library Association) 9) To add to responsibilities on certification of preservation materials for librarian. 10) To hold the constant committee system in each library. 11) To keep up with the ideal environment (humidity, temperature, light, ventilation, etc.) of preservation materials in the arrangement room, and to put on the gown.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7870-7877
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• 2015

In the case of CWR (Continuous welded rail) located on the railway bridge, the CWR has additional axial force due to interaction of bridge and track. Therefore, the CWR tracks located on the bridge have to secure the safety of running train and CWR track through mitigating influence for interaction of bridge and track. The railway design guide in Korea (KR C-08080) provides a certain value for property of longitudinal friction behavior of rail fastening system that is major parameter of interaction behavior by applying European codes. However, in order to apply to domestic railway, it is necessary to review property characteristics of the rail fastening system in actual use. In this paper, the experiment for longitudinal friction behavior of rail fastener applied to concrete track on the railway bridge in Korea was carried out, and statistical characteristic for property of the rail fastener was analyzed from the result of the experiment.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.9-15
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• 2018

According to the development and use of self-consolidating concrete in field, interest in material properties of early-age concrete is rising. Setting time with hydration process of cement is one of significant indicator to evaluate the early-age material properties of concrete, various nondestructive methods including penetration resistance measurement have been proposed to estimate setting time. This study performed an experimental approach to evaluate setting time delay in mortar adding superplasticizer using electrical resistivity measurement. For this purpose, total nine types of mortar samples were prepared, and its electrical resistivity was monitoring during 24h after mixing. From the experimental result, rising time of electrical resistivity was used to evaluate setting delay of mortar, and penetration resistance was also measured for comparison. In addition, dynamic elastic modulus and compressive strength of 1day mortar were measured to investigate a possibility the use of electrical resistivity measurement for evaluation of early-age material properties.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.307-310
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• 2010

Ubiquitous society to build basic infrastructure in the power supply and power equipment safety is important. U-City in order to prevent the disaster of U-IT Power Equipment Performance Module and the security for the safety of the U-City is necessary. In this paper, the power unit of U-IT module, temperature sensor, humidity sensor, equipped with sensors arranged throughout the fire, and home distribution boards, Home Network Wall-Pad, Blocker, MPNP black boxes, arc detection, arc safety equipment, outlet of the modular performance evaluation and security measures will be studied. U-IT power devices and sensors to analyze the information conveyed by proactive risk and ensure safety, access control, authentication, security safeguards, such as U-IT integrated management system for electrical safety and strengthen the security, safety and security with a U-City will contribute to the construction and operation.

• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.131-138
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• 2017

In this study, the expansion and compressive strength tests of emergency restoration material were carried out to restore cavity causing ground subsidence. The expansion and compressive strength characteristics according to component ratio of main material - hardener and mix proportion of blowing agent - accelerator were analyzed based on the test results. As a result of the relationship of curing time - expansion ratio analyses, it confirmed that expansion ratio decreased with reduced curing time regardless of mix proportion of blowing agent - accelerator in main material, if component ratio of hardener increased. This means that component ratio of the main material - hardener had greatly affected the expansion ratio. The compressive strength characteristics of emergency restoration material confirmed that strength was affected by mix proportion of blowing agent - accelerator. Therefore, it is necessary to apply reasonable component ratio and mix proportion to consider the required injection time, expansion ratio and strength of restoration material, when emergency restoration in ground cavity is required.

• Journal of Soil and Groundwater Environment
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• v.22 no.6
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• pp.120-128
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• 2017

The aim of this study is to analyze the accuracy of SRTM Ver 3.0 and ASTER GDEM Ver 2 over Korea. To enable this, accuracy analysis was performed by using precise DEM which was made with multiple aerial image matching and national base map benchmark. The result of this study identified both SRTM and ASTER have different features. The height of the SRTM was found to be higher (3.8 m on average) at lower elevation and lower (8.4 m on average) at higher elevation. In contrast, the ASTER was found to be lower than the actual height at both lower and higher elevation (2.92 m, 4.51 m on average). The cause of this height bias according to the elevation is due to the differences in data acquisition and processing methods of DEM. It was identified however that both SRTM and ASTER were within allowable limits of error. In addition, RMSE of the SRTM was smaller than the ASTER in comparison to benchmark, and also the bias trend both at higher and lower terrain were similar to the precise DEM which was made with multiple aerial image matching. Therefore, the reliability of SRTM can be considered to be higher.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.459-459
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• 2012

본 연구에서는 우리나라의 건설현장에서 발생하는 안전사고 발생 특성과 강수특성 변화의 연관성을 분석하였다. 대상기간 2000년부터 2010년까지 지역별 건설 산업현장에서의 사고발생 건수(한국산업안전보건공단) 자료와 같은 시기 지역별 강수량 자료(기상청 지상관측지점)를 사용하여 강수량의 거동과 건설현장 사고발생 건수의 거동 사이의 상관성을 분석하였다. 건설현장 사고사례의 사고형태 중 부상자와 사망자 정보를 사용하였으며 지역의 구분은 특별시, 광역시 및 도 단위로 구분하여 분석하였다. 분석결과 전반적으로 연간 강수량의 증가 추세와 유사하게 전체 건설현장 안전사고의 발생건수가 증가하는 추세를 보이며, 지역별로 강수량의 증감 거동과 유사한 사고발생의 빈도의 증감거동을 보였다. 우리나라의 평균 월강수량과 월별 건설 안전사고 발생건수는 0.8의 선형상관성을 가지며 지역별 분석에서는 섬지역인 제주도가 가장 높은 상관계수 0.9를 나타냈고, 서울특별시 0.7, 대구광역시 0.7, 광주광역시 0.7, 부산광역시 0.5, 인천광역시 0.5, 대전광역시 0.4의 상관관계 순으로 나타났다. 강수변화에 따른 지역, 계절, 월별 강수-건설재해 상관성을 분석 제시하였다. 장마철인 7~8월에는 봄철인 3월~5월에 비해 강수량의 증가뿐만 아니라 21.16%의 사고 발생건수 증가가 나타났으며 우리나라의 강수특성 중 기후변화로 인하여 태풍의 영향이 많았던 시기의 사고발생의 특성을 정량적으로 분석하였다. 특히 2002년 태풍 '루사'와 2003년 태풍 '매미' 발생 시 산업현장의 재해 발생이 많이 있었던 것으로 조사 되었는데, 그 이유로는 산업현장에 태풍의 영향으로 감전사고 발생률이 2배가량 증가하며, 구조물과 사면이 무너져 내리는 등 사고가 빈번히 발생하면서 재해발생률이 더 증가하였다. 이처럼 기후변화에 따른 강수특성 변화로 건설 산업현장은 사고의 위험에 더욱 노출되고 있으므로 이에 대한 지역적 특성 분석과 대책 수립이 요구된다.

• Land and Housing Review
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• v.11 no.1
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• pp.109-116
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• 2020

This study aims to establish an approach to assess urban flood vulnerability by identifying social characteristics such as the road transportation and the vulnerable groups. Assessment procedures comprise three steps as: (1) composing the assessment criteria to reflect the urban characteristics; (2) calculating the weight; and (3) evaluating the vulnerability. The criteria were adopted by Delphi survey technique. Four criteria as land cover, residents, vulnerable areas, and disaster response were adopted in the current study. To determine the weight set of criteria, subjective and objective methods were combined. The weight set was determined using the combined method which reflects the Delphi method and Entropy analysis. In the process of data-based construction, GIS tools wwere used to extract administrative unit materials such as land cover, road status, and slope. Data on population and other social criteria were collected through the National Statistical Office and the Seoul Metropolitan statistical data. TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) technique, which uses materials from cell units in order to rank the closest distance to the best case and the farthest distance from the worst case by calculating the distances to the area of assessment, was applied to assess. The study area was the Dorimcheon basin, a flood special treatment area of Seoul city. The results from the current study indicates that the established urban flood vulnerability assessment approach is able to predict the inherent vulnerable factors in urban regions and to propose the area of priority control.

• Water for future
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• v.11 no.2
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• pp.43-53
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• 1978

Synopsis: This study has systemized the results of construction and classification with 656 large dams in Korea which were defined in ICOLD provision. Especially, checking up the drainage capability of large capacity outlets and its of spillway, this paper suggests the planning of outflow discharge with large capacity outlets and spillway in future. The results of this study are following as; 1. The classification by purposes in Korea shows that irrigation dams are 94% in rate(607 dams), jydropower and multipurpose dams are 2% (14 dams), municipal and industrial water supply dams are 4% (26 dams). 2. In design of proposed outflow discharge, spillways of irrigation dams were selected outflow discharge on 100 years return period, those of municipal and industrial water supply dmas 200 years and those of hydropower and multipurpose dams 500 years or 1000 years. 3. Emergency spillway should be considered in the fields of disaster prevention engineering and the rank of return periods for the emergency proposed out flow discharge was suggested. 4. Some of problems are suggested for this subject in future.