• Journal of the Korean Society for Railway
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• v.16 no.5
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• pp.358-364
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• 2013

In the second part of the paper, a design strategy for an apartment complex constructed at a railway depot is proposed for vibration reduction purposes. Various design parameters such as the vehicle operating speeds, artificial land behavior, housing support structure, and apartment sub-structures are individually examined to reduce the transmission of vibrations through building structures. Building construction on an artificial land should be subjected to regulations that require the application of a vibration reduction scheme based on the mechanics that govern the vibration transmission phenomena. The implementation of these parameters at an early design stage will provide a quiet living environment for residents who may be exposed to excessive noise and vibration.

• Economic and Environmental Geology
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• v.26 no.3
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• pp.383-393
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• 1993

Paleomagnetic data have been obtained from the Lower Triassic Tonggo formation which is exposed in the E-W trending Baekunsan syncline comprising the Pyongan Supergroup in eastern Korea. Two ancient components of magnetization are recovered in this formation by detailed thermal demagnetization: a post-folding component and a pre-folding component The post-folding component ($D/I=58.8/55.5^{\circ}$) is normally magnetized and appears to acquire in the Cretaceous Normal Superchron. It is a magnetic signature of the Daebo Orogeny and has been rotated clockwise since this magnetization has been acquired, in common with the main synclinal axis. The pre-folding component ($D/I=1.1/19.4^{\circ}$, Paleopole at $306.1^{\circ}E$, $63.2^{\circ}N$) passes fold and reversal tests and is inferred to be a post-depositional or early chemical diagenetic remanence of Lower-Middle Triassic age. This paleopole corresponds only with the Lower Triassic poles from the North China Block: it is removed from the contemporary poles from the South China Block. If the result of this study is corrected for the clockwise rotation deduced from the Cretaceous overprint, the enhanced agreement with the Lower Triassic poles from the North China block can be achieved. Therefore, a first order correlation between the Korean Peninsula and North China at least since Lower Triassic times is identified in this study.

• Fire Science and Engineering
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• v.26 no.5
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• pp.61-66
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• 2012

In restroom on high-rise building, exhaust system comprising the blower and duct is installed to discharge the odor and the water is suppled. Thus the restroom with fire and flame protection system may be used as refuge area in a fire situation. The study presents the smoke-proof system which operates such that the exhaust system to discharge the odor is converted to air supply system and appropriate pressure difference between the restroom and the accommodation is maintained. Also real-scale test facilities of smoke-proof system for refuge space using a restroom are installed on 5-story smoke control test building and experiments for evaluating the operational performance of smoke-proof system are carried out.

• Economic and Environmental Geology
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• v.31 no.1
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• pp.45-52
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• 1998

Paleomagnetic data have been obtained from the Lower Triassic Tonggo Formation which is exposed in Tanyang area comprising the Pyeongan Supergroup in eastern Korea. Mean characteristic direction of the Tonggo Formation is declination/inclination=$121.4^{\circ}/-26.4^{\circ}$ (k=52.7, ${\alpha}_{95}=7.2^{\circ}$, N=9 Sites) and paleopole at longitude/latitude=$30.7^{\circ}E/33.3^{\circ}N$ ($dp/dm=4.2^{\circ}/7.8^{\circ}$). The mean direction passes reversal test and fold test at 99% confidence level. Therefore, it is inferred to be a pre-folding component. The paleopole position of this study is close to the Triassic pole positions of the North China Block; it is far from those of the South China Block. Therefore, a first order correlation between the Korean Peninsula and North China at least since Lower Triassic times is identified in this study.

• Journal of Environmental Impact Assessment
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• v.19 no.6
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• pp.583-590
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• 2010

To determine nocturnal inversion characteristics at the leeward side of high-rise building, air temperature data were observed at 10 minute interval from February 22, 2010 to April 15, 2010. The observed data were compared, analyzed and examined to illustrate air temperature differences between the roof (XAR) and surface (XAG) of X apartment. The wind speed, wind direction and precipitation data were also observed at XAR and YJL (Yangjae Stream) sites at the same time. After the analysis, the maximum nocturnal inversion was observed by $4.0^{\circ}C$ at 3:40, 3:50, 4:10 on February 24th 2010, at that time the weather condition was clear and weak wind. Air temperature inversions at the leeward side of high-rise building were observed on whole day in wintertime and air temperature inversion intensity was also higher than other nearby area (SMG).

• Proceedings of the Korean Society of Disaster Information Conference
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• 2015.11a
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• pp.127-129
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• 2015

최근 도심의 건물들은 수요자의 요구에 따라 평면이 다양화 되어가고 토지의 효율을 높이기 위하여 초고층화 되어가는 경향이 있다. 심지어 전통적인 공동주택의 개념으로 지어지는 아파트도 그 높이가 100m를 상회하는 경우가 대부분이다. 현재 국내의 구조설계 시 구조물의 동적특성 요소를 반영하는 고유 진동수는 주로 미국의 지진자료를 바탕으로 계산되게 되어있으며, 기존 연구결과 실측결과가 상당한 차이를 보이고 있어 이에 대한 검토가 요구되고 있다. 이에 본 연구에서는 내진설계의 기본이 되는 건물의 고유주기를 측정하고 내진성능을 평가하여, 보다 경제적인 내진설계 방안에 대한 제시하고자 한다. 또한, 벽식구조건물의 경우 구조설계 기준에서 제시하는 지진하중을 산정할 때, 실무자들이 구조형식을 선택하기가 곤란하여 어떤 주기산정 식을 사용해야 할지 혼란스러워 하는 경우가 많으므로, 기타 골조 식과 전단벽 식을 고려하는 경우를 구조물의 상시 미진동을 측정하여 고유 진동수 및 고유 주기를 비교하여 제시하였다. 연구결과 기타 골조 식에 의해 계산된 값은 매우 보수적으로 나타나서 이에 대한 검토도 필요하다고 사료된다.

• Journal of Korean Society of Disaster and Security
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• v.10 no.2
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• pp.35-41
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• 2017

Recently chemical intoxication related with the use of chemical extinguishing agents occurs frequently. With the industrialization, high-rising of building and increase of fire risk, we use the various extinguishing agents and the safe use become important. In this study I carried out the risk assessment of representative chemical extinguishing agents (HCFC-123, HFC-125) using the CHARM and got the meaningful qualitative outcome. This study is significant in that the risk assessment of chemicals was conducted using CHARM, chemical risk assessment tool. It is expected that the results will be utilized as the basic data for the national chemical safety management.

• Explosives and Blasting
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• v.35 no.1
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• pp.43-52
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• 2017

Mountain and hill areas occupy by more than 70% in South Korea and Rock drilling should be applied in order to reduce noisy & vibration from massive civil engineering business such as road expansion, high-way construction, subway construction and construction of site renovation such as a newly-built & re-development of apartment, newly-built of high-rising building in downtown area. As Blasting noise & vibration such as vibration, noise, fly rock etc caused by blasting operation from large small scale construction occurs, neighboring residents who demand the compensation file a civil complaint so that the business reach a deadlock. As the excavation method for these areas, There are blasting of micro-vibration, mechanical excavation method(Rock splitter, Breaker etc), similar blasting method(plasma, gel fragmentation etc) to date. In this study, we are trying to find the feature & performance which get improved economic feasibility & construct ability through improving sympathetic detonation of New KINECKER-I used in blasting of micro-vibration & formulation and would provide convenience for use by introducing standard blasting pattern & construction method. Also, checked and confirmed all the blasting with connecting cap has been cleary detonated.

• Journal of the Earthquake Engineering Society of Korea
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• v.16 no.3
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• pp.23-33
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• 2012

Dynamic response measurements from natural excitation were carried out for three 18-story office buildings to determine their inherent properties. The beam-column frame system was adopted as a typical structural form, but a core wall was added to resist the lateral force more effectively, resulting in a mixed configuration. To extract modal parameters such as natural frequencies, mode shapes and damping ratios from a series of vibration records at each floor, the most advanced operational system identification methods based on frequency- and time-domain like FDD, pLSCF and SSI were applied. Extracted frequencies and mode shapes from the different identification methods showed a greater consistency for three buildings, however the three lower frequencies extracted were 1.2 to 1.7 times as stiff as those obtained using the initial FE models. Comparing the extracted fundamental periods with those estimated from the code equations and FE analysis, the FE analysis results showed the most flexible behavior, and the most simple equation that considers the building height as the only parameter correlated fairly well with test results. It is recognized that such a discrepancy arises from the fact that the present tests exclude the stiffness decreasing factors like concrete cracking, while the FE models ignore the stiffness increasing factors, such as the contribution of non-structural elements and the actual material properties used.

• Fire Science and Engineering
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• v.27 no.2
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• pp.25-30
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• 2013

'Heaundae Woosin Building' fire was the case that a fire breaking out on the $4^{th}$ floor spread out the $38^{th}$ floor which is a top story and the penthouse was destroyed by fire. After this fire, the fire safety for high rise buildings has been on the rise and several new laws and regulations related in the buildings were created. The study is to analyze Heaundae officetel building case using FDS which is one of the CFD programs for fire. The methodology of this study is to analyze the case comparing with fire spread and route from a virtual fire simulation and related articles and a video clip of actual scene fire. This study shows that a fire spreading on top of levels spent approximately 30 minutes and, which is similar to the actual fire case. Also the pattern of spread has similarity with the case. However, even if the actual fire case shows the fire pattern was "V shape", the smoke-view presents the fire dose not spread horizontally as much as the real fire case. The result shows uncertainty of the modeling based on many grids and a limitation of putting interior finish input sources and the direction of the wind might cause the difference. Also, to analyze factors influencing on a vertical fire, another fire modeling is performed by in condition of modeling environment considering concrete interior finish between buildings and no wind. The result presents the fire spread in smoke-view does not spread vertically as much as the actual case.