• The Journal of Engineering Geology
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• v.18 no.2
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• pp.191-196
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• 2008

This study is a case study for application of the RTI warning model to Korea which was previously developed to predict landslide potential and occurrence time during a rainfall event. The rainfall triggering index (RTI) is defined as the product of the rainfall intensity I (mm/hr) and the effective accumulated rainfall $R_t$ (mm). This index is used to evaluate the landslide and debris-flow occurrence potential at time t during a rainfall event. The upper critical value ($RTI_{UC}$) of RTI and the lower critical value ($RTI_{LC}$) of RTI can be determined by historical rainfall data of a certain area. When the rainfall intensity exceeds the upper critical value, there are high potential to occur land-slides. The analysis result can predict landslide occurrence time of an area during a rainfall event as well as land-slide potential. The result can also be used as an important data to issue early-warning of landslides. In order to apply the RTI warning model to Korea this study analyzed rainfall data and landslides data in Inje county, Gangwon province, Korea from July 13 to July 19, 2006. According to the analysis result, the rainfall intensity exceeded the upper critical value 23 hours ago, 11 hours ago, and 9 hours ago from 11:00 in the morning, July 16. Therefore, landslide warnings would be issued three times for people evacuation for avoiding or reducing hurts and dam-ages from landslides in mountainous areas of Inje.

• Journal of Korea Water Resources Association
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• v.54 no.spc1
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• pp.1119-1130
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• 2021

Urban flooding caused by localized heavy rainfall with unstable climate is constantly occurring, but a system that can predict spatial flood information with weather forecast has not been prepared yet. The worst flood situation in urban area can be occurred with difficulties of structural measures such as river levees, discharge capacity of urban sewage, storage basin of storm water, and pump facilities. However, identifying in advance the spatial flood information can have a decisive effect on minimizing flood damage. Therefore, this study presents a methodology that can predict the urban flood map in real-time by using rainfall data of the Korea Meteorological Administration (KMA), the results of two-dimensional flood analysis and random forest (RF) regression model. The Ujeong district in Ulsan metropolitan city, which the flood is frequently occurred, was selected for the study area. The RF regression model predicted the flood map corresponding to the 50 mm, 80 mm, and 110 mm rainfall events with 6-hours duration. And, the predicted results showed 63%, 80%, and 67% goodness of fit compared to the results of two-dimensional flood analysis model. It is judged that the suggested results of this study can be utilized as basic data for evacuation and response to urban flooding that occurs suddenly.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.129-138
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• 2019

In this study, the rebar rock bolt sensor and GFRP rock bolt sensor, which can be monitored, were embedded in a large model slope, and the behavior of slopes occurred in the early stage of slope collapse was analyzed after performing the field failure test, numerical analysis of the individual element method and finite element method. By comparing and analyzing the field test and numerical analysis results, field applicability of rock slope collapse monitoring on the rebar rock bolt sensor and GFRP rock bolt sensor was investigated. Through this study, smart slope collapse prediction and warning system was developed, which can be used to induce effective evacuation of residents living in the collapsible area by detecting landslide and ground decay precursor information in advance.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.12
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• pp.1089-1096
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• 2015

A marine helicopter should remain sufficiently upright to permit safe evacuation of all personnel with a flotation system. And the rule requires that after ditching in water, the adequate flotation time will allow the occupants to leave the rotorcraft. To this end, stability test of the emergency flotation system for Korean marine helicopter was performed by using "Froude scaling method" in water tank. Test configuration and conditions were determined in consideration of the helicopter loading condition and related specifications. Test results meet the stability requirements at sea state code 4 and sea state code 2 with puncture conditions.

• Composites Research
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• v.33 no.5
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• pp.302-308
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• 2020

We measured the thermal conductivity of composite materials manufactured by the autoclave and vacuum bag only processes and predicted the cure behavior of the external and internal of composite parts with a cure kinetics model. The temperature difference between the external and internal depends on the processes because of the change of thermal conductivity. In the autoclave process, the temperature and cure behavior of the internal were similar to those of the external because of the high thermal conductivity. However, the temperature of the internal of the vacuum bag only process was different from that of the external. The difference can influence the part quality and evacuation of air. Compression tests were performed to find the mechanical property using 0° unidirectional specimens. The composite of the vacuum bag only process was found to have a lower compressive strength than that of the autoclave process.

• Tunnel and Underground Space
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• v.7 no.2
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• pp.100-107
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• 1997

In case of a fire outbreak in a uni-directional road tunnel, the flow of traffic immediately behind the fire disaster will be stalled all the way back to the entrance of the tunnel. Furthermore, when the vehicle passengers try to flee away from the fire toward the entrance of the tunnel, the extremely hot fume that propagates in the same direction will be fatal to the multitudes evacuating, but may also cause damage to the ventilation equipments and the vehicles, compounding the evacuation process. This paper will present the 3-dimensional modelling analysis of the preventive measures of such a fume propagation in the same direction as the evacuating passengers. For the analysis, the fire hazard was assumed to be a perfect combustion of methane gas injected through the 1 m X 2 m nozzle in the middle of the tunnel, and the product of $CO_2$ as the indicator of the fume propagation. From the research results, when the fire hazard occurred in middle of the 400 m road tunnel, the air density decreased around the fire point, and the maximum temperatures were 996 K and 499 K at 210 m and 350 m locations, respectively, 60 seconds after fire disaster occurred, when the fumes were driven out only towards the exit-direction of the tunnel. By tracing the increase of $CO_2$ level over 1% mole fraction, the minimum longitudinal ventilation velocity was found to be 2.40 m/sec. Furthermore, through Analysis of the temperature distribution graphs, and observation of the cross-sectional distribution of $CO_2$ over 1% mole fraction, it was found that the fume did not mix with the air, but rather moved far in a laminar flow towards exit of the tunnel.

• Journal of Korean Neurosurgical Society
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• v.52 no.4
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• pp.320-324
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• 2012

Objective : The purposes of this study are to investigate the factors that may be related to ventriculoperitoneal (VP) shunt in patients with cerebellar hematoma and the effect of severe fourth ventricular hemorrhage, causing obstructive hydrocephalus on subsequent VP shunt performance. Methods : This study included 31 patients with spontaneous cerebellar hematoma and concomitant fourth ventricular hemorrhage, who did not undergo a surgical evacuation of hematoma. We divided this population into two groups; the VP shunt group, and the non-VP shunt group. The demographic data, radiologic findings, and clinical factors were compared in each group. The location of the hematoma (whether occupying the cerebellar hemisphere or the vermis) and the degree of the fourth ventricular obstruction were graded respectively. The intraventricular hemorrhage (IVH) score was used to assess the IVH severity. Results : Ten out of 31 patients underwent VP shunt operations. The midline location of cerebellar hematoma, the grade of fourth ventricle obstruction, and IVH severity were significantly correlated with that of VP shunt operation (p=0.015, p=0.013, p=0.028). The significant variables into a logistic regression multivariate model resulted in statistical significance for the location of cerebellar hemorrhage [p=0.05; odds ratio (OR), 8.18; 95% confidence interval (CI), 1.00 to 67.0], the grade of fourth ventricle obstruction (p=0.044; OR, 19.26; 95% CI, 1.07 to 346.6). Conclusion : The location of the cerebellar hematoma on CT scans and the degree of fourth ventricle obstruction by IVH were useful signs for the selection of VP shunt operation in patients with spontaneous cerebellar hematoma and concomitant acute hydrocephalus.

• Korean Security Journal
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• no.5
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• pp.19-40
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• 2002

For front, aspect of terror may have to prepare indeed even chemical terror or rocket and small size missile and radioactivity terror because is predicted to become various. Furthermore, when see motion of every countries about nuclear engineerses' bringing round and illicit sale of plutonium, our country may have to prepare in terrorism which is expected thus. So that can finish international event successfully because the United States of America supports great manpower and budget since New York's World Trade Center terror and when see that is considering terror prevention countermeasure, we operate temporarily bursting tube state complete charge team such as terror by each field specialist such as a concern interested including special CBR complete charge moving team among 2002 World Cups soccer game period ahead of international event, must consider safety countermeasure. Specially, biology weapon of chemical weapon and cholera etc. 13 kinds of 5000ton that North Korea plans CBR terror society confusion that North Korea that to terror support nation as well as nuclear weapons development suspicion is defending South Korea communization strategy as real condition that is amplified as well as is saving production brand gets imprinted uses CBR terror at normal times, when see that is planing powerlessness communization unity using CBR weapon at time of war, must operate until bias 2002 World Cups international event finishes cooperation safety countermeasure utensil safely under closer talk between the South Korea ${\cdot}$ Japan ${\cdot}$ North Korea. As for us which must serve 2002 World Cup successfully to accomplish perfectly preparedness of CBR terror firstly, all inhabitants knows well CBR protection trick, and secondly, CBR existing formation that solidify realignment CBR complete charge moving team which of course is consisted of CBR specialist compose and keeping immediate going out attitude operating, by third, that expand CBR individual protection equipment and CBR evacuation equipment and establish individual and group protection attitude naturally, supplement as there is main room that actualize CBR pollution patient's slogan countermeasure by fourth, and develop standard model for CBR terror provision by fifthBecause constructing infra of CBR safety establishing CBR preparedness that utilize it, must minimize damage and contribute inhabitants' life and property protection.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.3
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• pp.231-238
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• 2017

Using 3D based BIM(Building Information Modeling) enables a variety of construction simulations. The is no case to simulate BIM demonstration experiment on deeply immersed virtual reality environment in korea. This paper develops a multi screen based simulation system to enable 3D based immersed environment to diverse decision making and virtual construction simulation. In a developed simulation laboratory, we can carry out BIM drawing review, disaster evacuation simulation, constructability review on wild land and design urban planning using haptic device on 3-side space with 4K resolution . Also, It can review large amount of drawings without data conversion because of compatibility with BIM software.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.6
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• pp.451-462
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• 2011

The smoke control system plays the most important role in securing evacuation environment when a fire occurs in road tunnels. Smoke control methods in road tunnels are classified into two categories which are longitudinal ventilation system and transverse ventilation system. In this study it is intended to review the characteristics of smoke behavior by performing numerical analysis for calculating the optimal smoke exhaust air volume with scaled-model and simulation when a fire occurs in tunnels in which transverse ventilation is applied, and for obtaining the basic data required for the design of smoke exhaust systems by deriving optimal smoke exhaust operational conditions for various conditions. As a result of this study, when the critical velocity in the tunnel is 1.75 m/s and 2.5 m/s, the optimal smoke exhaust air volume has to be more than $173m^3/s$, $236m^3/s$ for the distance of the smoke moving which can limit the distance to 250 m. In addition, in case of uniform exhaust the generated smoke is effectively taken away if the two exhaust holes near the fire region are opened at the same time.