• Journal of Korean Tunnelling and Underground Space Association
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• v.3 no.4
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• pp.35-55
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• 2001

Recently, as tunnel structures are getting older and decrepit, many tunnel inspections are carried out for evaluating the tunnel state and safety. But, because there is no exact standard for tunnel state and safety, depending on subjective decision, the new standard to assess the tunnel state is required. The existing standard including mainly the assessment of the state of tunnel lining is not considered the characteristics of tunnel as underground structures. Also, the item of assessment and process of grading and classifying the state of tunnel is not objective and systemetic. In this study, new standard for assessment of tunnel state is presented for improving the problems in evaluating the tunnel state and safety. In the new standard, the new items of assessment including geotechnical condition were selected and graded, the process in classifying the tunnel state is quantitative for objective assessment for tunnel state. This new standard and method is practically used in effective safety inspection and diagnosis and tunnel maintenance.

• Journal of the Korean Institute of Gas
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• v.21 no.5
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• pp.64-69
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• 2017

South Korea is the world's second-largest importer of LNG and possess about 70 tanks which are in operation by 2017. Thirty years as the design warranty period have exceeded since LNG storage tanks as the core facility of LNG industry were constructed in 1986. The LNG storage tank is under precision safety diagnosis from 2014 due to urban gas business act amendment. There is no criteria of condition evaluation for outer tank of LNG storage tank at the time of precision safety diagnosis. Through analysis of structural characteristic of LNG storage tank and civil structure condition evaluation standards, the criteria of condition evaluation for main members was developed. The criteria of objective condition evaluation can improve safety and reliability of LNG storage tank and suggest matenance criteria.

• JOURNAL OF ELECTRICAL WORLD
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• no.7 s.127
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• pp.96-99
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• 1987

최근설비를 계획하는데 있어서는 설계에서 건설 운용, 갱신에 이르기까지 라이프사이클코스트, 미니멈의 관점에서 시스템토틀로서 검토되는 일이 많다. 그러한 의미에서 설비의 보전기술을 중요한 역할을 담당한다. 일반적으로 보전의 종류는 사후, 예방, 예지()의 각 보전에, 또 보전의 방식으로는 시간기준보전과 상태기준보전으로 대별할 수가 있다. 설비가 복잡하고 고도화되어가고 있는 가운데 경비효율, 가동율, 신뢰도 등 토틀 시스템 효율의 향상을 도모하기 위해 상태기준에 의한 예지보전이 요구되는 경향에 있다. 또 온라인으로 리어얼타임인 설비진단기술의 진전이 이를 가능케 해가고 있다. 여기서는 음행분석에 의한 설비진단에 대해 자가발전장치의 음향진단을 예로 하여 기술키로 한다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.5
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• pp.553-561
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• 2015

In this study, the performance assessment criterion for reasonable maintenance of shield TBM tunnel was presented. The performance assessment items such as crack, leakage, breakage, spalling, exfoliation/detachment, efflorescence, quality condition, exposure of steel, carbonation, faulting step, bolts condition, drainage condition, ground condition, contact section condition and conduit condition were selected by analyzing domestic and foreign performance assessment criterions and investigating segment lining deterioration cases through the site investigation and in-depth inspection analysis result on the shield TBM tunnel. In addition, the reasonable weight using AHP (Analytic Hierarchy Process) were estimated.

• Journal of the Korean Institute of Gas
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• v.22 no.6
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• pp.44-51
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• 2018

As the LNG storage tank is aged, if there is a crack in the outer wall concrete or corrosion of the reinforcing steel, there is a risk of a major accident such as collapse of the structure depending on the type and degree of damage. Since 2014, LNG storage tanks have undergone precise safety diagnosis and safety inspection has been carried out. The condition evaluation criteria for each component have been revised and applied in January 2016. The condition evaluation standard is to evaluate the status of storage tanks based on the appearance survey and material test results of LNG storage tanks and it is important for maintenance. In addition, the representative condition evaluation standard that shows the comprehensive state of each LNG storage tank is important in maintenance, but the related standard for LNG storage tank outer concrete is not available in Korea and abroad, and development of the condition evaluation standard is necessary. In this paper, we examined the structural characteristics of LNG storage tanks, analyzed the status of the condition evaluation criteria for each member, and developed a comprehensive status rating system by weighting the members. We used the AHP(Analytic Hierarchy Process) technique and developed a representative conditon evaluation criteria through surveys of professional organizations.

• Explosives and Blasting
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• v.28 no.2
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• pp.119-132
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• 2010

There are many dispute with a construction due to such environment problem as vibration and noise. Generally, we have a standard for acceptance level in land. But we have not a sufficient standard for acceptance level or guide line in underwater sound. In other countries, a acceptance level or guide line in underwater sound has been suggested. Especially the management criterion of underwater noise for fish has bee suggested using the measurement data (peak pressure, rms, energy and SEL) by a hydrophone. In Korea, there is no management criterion of underwater noise for fish. This study suggested the management criteria of underwater noise for fish based on the measured data by a hydrophone.

• Proceedings of the Korea Contents Association Conference
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• 2016.05a
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• pp.119-120
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• 2016

한국의 도로교통법에는 주취상태에서 운전을 하면 안 된다는 규정이 있다. 그런데 주취운전이라는 말보다 음주운전이라는 말이 더 널리 쓰이는 실정이다. 음주운전 역시 말 그대로 술을 마신 상태에서 하는 운전을 말한다. 우리나라를 비롯한 모든 나라에서는 주취운전의 위험성을 고려하여 이에 대한 단속 기준을 제시하고 있다. 한국은 혈중알콜농도를 확인하는데, 0.05를 단속 기준으로 삼고 있으며 현재 단속기준에 대한 논의가 이루어지고 있다. 경찰은 현재의 음주운전 단속 기준을 0.03%로 강화하는 것에 대하여 의견을 수렴 중이다.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 1995.03a
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• pp.67-81
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• 1995

암반 구조체를 해석하기 위해서는 파괴전의 응력-변형률 거동뿐만 아니라 파괴를 구성하는 삼차원 응력 상태를 알아야 한다. 암반의 파괴를 지배하는 조건을 결정하기 위해서는 일반적인 삼차원 파괴기준이 필요하다. 암반의 파괴를 이루는 응력상태를 파악하기 위해 많은 실험적 연구가 수행되었으며 특히 장비의 사용에 있어서 하중 메카니즘과 시료의 경계조건의 개선에 많은 연구가 진행되었다. 암반의 파괴조건을 설명하는 데에는 이러한 기본적인 기준들 이외에도 경험적인 기준들이 사용되어 왔다. Hoek 와 Brown 은 비등방성 재료의 강도에 대해 연구하였고 순수암(intact rock)의 강도에 대한 경험적인 기준을 제안하였다. (중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1125-1131
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• 2016

The purpose of this paper is to establish an evaluation criteria for pavement condition in bicycle road. The suggested criteria would help in the activation policy of bicycle use. The conventional evaluation criteria is difficult to be applied for the bicycle road since the bicycle road is sensitive to changes in the driving environments such as obstacles and bumps. This study presents the evaluation criteria that is suitable for bicycle road. The criteria was suggested in 5 grades through the impact acceleration range of RMSI (Road Monitoring System using ICT). The grades of the criteria are divided into a range of grade A to E. The grade A is a very good condition, while the grade E is a state that requires immediate maintenance. This study were confirmed the validity through the survey of user's satisfaction. According to the results of survey, the grade A was shown correlation of 91%. The grade E requiring immediate repair was presented correlation of 94%. It showed that the results of surveying the bicycle road users are highly correlated with the suggested criteria for pavement condition. It showed that the criteria are highly correlated with the survey results. Suggested criteria using the RMSI is expected to be effective for maintenance of the bicycle road. In addition, it is expected to ensure the serviceability and safety for the bicycle users.

• Proceedings of the KIEE Conference
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• summer
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• pp.76-78
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• 2004

본 논문에서는 전력시스템에서 상정 사고로 인해서 부하가 급변할 때 계통의 신뢰도를 유지하기 위해서 발전 모선의 전압을 조절하여 부하 모선의 전압을 정상상태의 범위에서 유지시키기 위한 알고리즘을 구조개편 후 비상시에 취할 수 있는 중요한 조치 중 하나로서 재조명한파. 이에 먼저 전력 계통의 상태를 발전기의 예비력을 기준으로 정상상태와 비상상태로 나누고, 계통에서 발생한 상정사고에 대하여 발전 모선의 전압변동을 통해서 부하 모선의 전압을 정상상태의 범위에서 유지하도록 한다. 하지만 심각한 상정사고가 발생하여 발전기의 출력이 정상상태의 예비력 기준을 초과하여 발전을 해야만 하는 상황이면, 이를 계통의 비상상태로 선언하고, 이를 다시 정상상태로 회복시킬 수 있도록 하는 새로운 알고리즘을 제안하였다.