• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.341-351
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• 2015

When rainfall occurred on road tunnel, that is likely to have influence upon ventilation force in the tunnels but the tunnels ventilation system did not consider factors of rainfall. Thus, this study investigated effects of rainfall upon ventilation force in the tunnels at no rainfall and changing of rainfall by 3 dimensional numerical method. Flow rate into road tunnels decreased as many as 52.34% at rainfall of 150 mm/hr, and pressure drop of road tunnel between entrance and exit decreased as many as 22.22%, so that rainfall had influence upon ventilation force in the tunnel. The number of necessary jet fan in road tunnels is 12 at no rainfall but, when rainfall of 80 mm/hr on road tunnels, the number of necessary jet fan in road tunnels is 16, when rainfall of 150 mm/hr on road tunnels, the number of necessary jet fan in road tunnels is 17. So, factor of rainfall should be considered at estimation of ventilation system of road tunnel.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2595-2602
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• 2009

Hexamer cluster of N,N-dimethylformamide(DMF) based on the crystal structure was investigated for the equilibrium structure, the stabilization energies, and the vibrational properties in the density functional force field. The geometry (point group $C_i$) of fully optimized hexamer clustered DMF shows quite close similarity to the crystal structure weakly intermolecular hydrogen bonded each other. Stretching force constants for intermolecular hydrogen bonded methyl and formyl hydrogen atoms with nearby oxygen atom, methyl C–H${\cdots}$O and formyl C–H${\cdots}$O, were obtained in 0.055 $\sim$ 0.11 and $\sim$ 0.081 mdyn/$\AA$, respectively. In-plane bending force constants for hydrogen bonded methyl hydrogen atoms were in 0.25 $\sim$ 0.33, and for formyl hydrogen $\sim$ 0.55 mdynÅ. Torsion force constants through hydrogen bonding for methyl hydrogen atoms were in 0.038 $\sim$ 0.089, and for formyl hydrogen atom $\sim$ 0.095 mdynÅ. Calculated Raman and infrared spectral features of single and hexamer cluster represent well the experimental spectra of DMF obtained in the liquid state. Noncoincidence between IR and Raman frequency positions of stretching C=O, formyl C–H and other several modes was interpreted in terms of the intermolecular vibrational coupling in the condensed phase.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.7
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• pp.823-828
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• 2012

The soft recoil mechanism was an effective mechanism for reducing the recoil force by forwarding momentum. There were some parameters such as the fire angle, firing position, and initial pressure of the recuperator, which influenced the forwarding momentum. These parameters affected the generation of the forwarding momentum in the soft recoil mechanism. To design for the mechanism, the parameters affecting momentum were studied to consider some reasonable conditions. Among the various parameters, the initial pressure of the recuperator and firing position was confirmed as a key factor to have affected the momentum. It was determined that the recoil force had a minimum value when the initial pressure of the recuperator was 180.

• The Korean Journal of Emergency Medical Services
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• v.28 no.1
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• pp.63-76
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• 2024

Purpose: To analyze trends related to demography and EMS and to provide supporting data for the appropriate deployment of EMS providers. Methods: In this cross-sectional study, data on patients transported by 119 EMS, demographics, and EMS factors were collected using the Korean Statistical Information Service (KOSIS) and the National Fire Agency annual report from 2017 to 2021. Results: During the study period, the total number of patients and those with severe disorders transported via 119 EMS showed an increasing trend. The total fertility rate and population during the same period tended to decrease, and the population density and number of households increased; however, there was a disparity between regions. The main demographic factors affecting the number of patients transported were population density and total fertility rate, while the main EMS factors were the number of ambulances and provision of emergency medical information services(hospital guidance, pharmacy information, and first aid guidance). Conclusion: From the perspective of EMS providers' force deployment, it is necessary to consider population density, population, number of households, total fertility rate, and number of emergency medical institutions and to strengthen the role of diverting the use of 119 EMS by minor patients by providing emergency medical information.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.252-259
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• 1997

A method to automate hazard analysis of chemical plants is proposed in this paper. The proposed system is composed of three knowledge bases - unit knowledge base, organizational knowledge base and material knowledge base, and three hazard analysis algorithms - deviation, malfunction and accident analysis algorithm. Hazard analysis inference procedure is developed based on the actual hazard analysis procedures and accident development sequence. The proposed algorithm can perform hazard analysis in two methods and represent all conceivable types of accidents using accident analysis algorithm. In addition, it provides intermediate steps in the accident propagation, and enables the analysis result to give a useful information to hazard assessment. The proposed method is successfully demonstrated by being applied to diammonium phosphate manufacturing process. A system to automate hazard analysis is developed by using the suggested method. The developed system is expected to be useful in finding the propagation path of a fault or the cause of a malfunction as it is capable to approach causes of faults and malfunctions simultaneously.

• Journal of Families and Better Life
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• v.31 no.6
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• pp.39-51
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• 2013

Because of the increasing demand for day care centers, The Korean government has enforced childcare accreditation. The government has created the evaluation certification system for child care facilities. But the system includes variable items, and the physical rules are not sufficient for ensuring security and quality amenities. So this study, through literature search, examined the rules of Child Care Centers in the U.S. and compared them with those in Korea focusing on the provision of security and amenities. The standards found in 4 U.S. states were investigated, and the results are as follows. The rule pertaining to the size of indoor activity spaces in C.C.C. allows the spaces to be smaller in Korea than in the U.S. There is no specific criterion for infants and toddlers in our standard. When comparing the standards of Korea with those of the United States, Korea's standards do not state specific rules about child care facilities such as indoor furniture, finishes and space planning. Additionally, the binding force ensuring compliance with the standards of physical facilities is weak. Thus, the ratings of child care standards for the physical environment should be presented in detail. And if a center does not comply with the criteria, stronger penalties will have to be imposed.

• Journal of Korean Association for Spatial Structures
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• v.20 no.3
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• pp.81-89
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• 2020

As the damage caused by earthquakes gradually increases, seismic retrofitting for existing public facilities has been implemented in Korea. Several types of structural analysis methods can be used to evaluate the seismic performance of structures. Among them, for nonlinear dynamic analysis, the hysteresis model must be carefully applied because it can significantly affect the behavior. In order to find a hysteresis model that predicts rational behavior, this study compared the experimental results and analysis results of the existing non-seismic reinforced concrete frames. For energy dissipation, the results were close to the experimental values in the order of Pivot, Concrete, Degrading, and Takeda models. The Concrete model underestimated the energy dissipation due to excessive pinching. In contrast, the other ones except the Pivot model showed the opposite results with relatively little pinching. In the load-displacement curves, the experimental and analysis results tended to be more similar when the column axial force was applied to columns.

• Journal of the Korea Society for Simulation
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• v.17 no.3
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• pp.45-51
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• 2008

The enemy will attempt to destroy our troop's core facilities using various fire supports at the beginning of war. Among these fire supports, artillery is given a most deal of weight and mine artillery is a great threat to our troops because it has a superior predominance on the ability of survival. A study about hitting mine artillery has been developed inside the military field only. However, these studies had been mostly qualitative analyses, thus having limitations in the aspects of nonobjectiveness and simplicity. Current study attempts to develop theory on hitting mine artillery beginning from mine opening until the target got hit, based on the assumption that one side which has inferior force will attack first. We studied on hitting mine artillery in a quantitative way using DEVS method.

• Asia Marketing Journal
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• v.7 no.3
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• pp.105-119
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• 2005

Samsung Fire & Marine Insurance Co., Ltd. launched 'Samsung Super Insurance Package', an insurance policy combining household's property & casualty insurance policies, except insurance with savings and pension insurance, into one for the first time in Korea. The product was developed to tackle challenges and threats from environmental changes, whose success owes to an excellent marketing strategies like adopting MCS system which is coined to support sales force activities, and building SRC(Samsung Risk Consultant), the organization dedicated to the sales of the product. The case shows how Samsung Fire & Marine Insurance Co., Ltd. developed and successfully marketed the combined insurance policy for the first time in Korea identifying the key success factors and discusses its business implications and future challenges.

• Fire Science and Engineering
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• v.30 no.4
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• pp.82-87
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• 2016

The ventilation system for the efficient operation of the building services systems in the ventilation plan of super high-rise buildings is used to combine smoke control systems. This study evaluated models of super high-rise buildings with four basement levels and 59 stories and investigated the pressure distribution of each floor by the smoke driving forces by numerical analysis. The smoke driving forces on the building of analytical model was analyzed to determine the effects of the ventilation plan and smoke control plane. In addition, when a combination with ventilation and smoke control of the kitchen ventilation damper in the ventilation plan of analysis model building was designed based on the these results, the relationship between the opening and closing force of the damper and smoke driving combined forces to act on the design pressure of the damper by a motion analysis simulation. The driving units of the damper were selected from the analytical results.