• Fire Science and Engineering
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• v.21 no.3
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• pp.91-96
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• 2007

Performance analysis of the butterfly valve in water fire extinguishing has been carried out. Performance analysis of the butterfly valve are investigated for torque characteristics, pressure loss and cavitations. The torque characteristics of disc are corrected for the angles of attack of valve disc by theoretical torque equation, and correction equation is added. The pressure loss coefficient on opening angle of valve has been formulated by applying the Carnot's equations. The torque characteristics, pressure loss and cavitations of the butterfly valve are analyzed for the ratio of disc thickness to the valve diameter. Cavitations are analyzed from the pressure loss coefficient of valve. The analysis of pressure loss and cavitation has been carried out change of the thickness ratio on opening angle of valve. These analysis data are utilize to necessary engineering data to develope of the butterfly valve.

• Advances in Computational Design
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• v.4 no.2
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• pp.91-118
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• 2019

Every year, many people are severely injured or lose their lives in accidents such as fire, chemical spill, public pandemonium, school shooting, and workplace violence. Research indicates that the fate of people in an emergency situation involving one or more hazards depends not only on the design of the space (e.g., residential building, industrial facility, shopping mall, sports stadium, school, concert hall) in which the incident occurs, but also on a host of other factors including but not limited to (a) occupants' characteristics, (b) level of familiarity with and cognition of the surroundings, and (c) effectiveness of hazard intervention systems. In this paper, we present EVAQ, a simulation framework for modeling large crowd evacuation by taking into account occupants' behaviors and interactions during an emergency. In particular, human's personal (i.e., age, gender, disability) and interpersonal (i.e., group behavior and interactions) attributes are parameterized in a hazard-impacted environment. In addition, different hazard types (e.g., fire, lone wolf attacker) and propagation patterns, as well as intervention schemes (simulating building repellent systems, firefighters, law enforcement) are modeled. Next, the application of EVAQ to crowd egress planning in an airport terminal under human attack, and a shopping mall in fire emergency are presented and results are discussed. Finally, a validation test is performed using real world data from a past building fire incident to assess the reliability and integrity of EVAQ in comparison with existing evacuation modeling tools.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.6
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• pp.1106-1112
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• 2010

One of the considerations in weapon systems procurement is the objective of maximizing the current force. Also, offensive effects, rather than defense are valued in weapons system development and procurement. Especially, the survivability of a naval ship is equally important as the offensive effect of onboard weapons. In case of naval ships, development of attack tactics and research regarding damage minimization must be conducted through live fire exercise against actual targets in order to minimize damage from the enemy. However, it is difficult to conduct such adequate measures due to realistic limitations such as time and budget in order to verify and calculate a weapon system's attack and damage effects along with the lack of practical studies in this subject despite numerous interests. Research are being conducted utilizing M&S to estimate attack effects and study damages due to such reason, but the lack of authoritative data and development ability are limiting calculation of reliable results. Therefore, this study will propose a measure to increase survivability of a weapon system(ship/vessel) utilizing research of vulnerability from enemy attacks analysis method against a naval ship(Craft Air Cushion).

• Journal of the Korean Statistical Society
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• v.6 no.1
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• pp.65-76
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• 1977

The relative importance of single-shot kill probabilities, rates of fire, weapon allocation strategies, and the size of initial force in warfare between two force with heterogeneous multiple weapon systems are considered by examining their effect on a natural measure of effectiveness, the expected number of survivors. Attrition equations are derived via stochastic formulation to represent the mean course of battle having an underlying probability distribution. It is assumed that each side uses indirect area fires. Level of intelligence activities are reflected in the availability of spontaneous information on the current enemy status. Depending on the availability of the information on the current enemy status, each participatory unit may follow 1) a prescribed attack pattern (fraction of the available units assigned to various enemy targets) or 2) an adaptive attack pattern depending on the enemy status at that time. Conditions for possible stalemate are discussed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.219-220
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• 2010

The purpose of this study is to evaluate chloride ion attack durability of concrete structure having experienced the high temperature fire. Mechanical properties and anti chloride ion diffusivity of concrete specimens were measured which have experienced of 2 hours heating at $200{^{\circ}C},\;400{^{\circ}C},\;600{^{\circ}C},\;800{^{\circ}C}$. The coupling FE model of thermal transfer and chloride ion diffusion was built to predict the life expectancy of RC structure using the property values by a series of experiment.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.375-376
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• 2008

Recently the increase of natural disaster and man-made disaster, newly emerging infectious diseases and bioterrorism attack changed the world in many aspects. So the Ministry of Health and Welfare and other related agencies are trying to solve the problems with disasters. We discussed these problems in the following eleven categories. (1) emergency medicine (2) communicable disease control, (3) food safety control, (4) public facilities safety, (5) social welfare facilities safety, (6) bioterrorism control, (7) geriatric health care, (8) insurance support, (9) overseas disaster victim support, (10) national organization protection, (11) fire fighter safety in forest fire. Through the reviews on the various kinds of disaster, we proposed the disaster control measure for the near future.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.88-99
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• 1996

Impotence is defined as a consistent inability to achieve or maintain penile erection that is adequate for completion of sexual intercourse. In oriental midicine, the chief cause of impotence is the decline of the fire from the gate of life, and in western medicine that is psycogenic and organic. Because of the increase aging people and psycologic stress that modern people get, impotence became common. This bibliographic study on impotence in the oriental and western medicine books has come to the following conclusions. 1. The main cause of impotence in the oriental medicine is the decline of the fire from the gate of life(命門火衰), followed by the deficiency of both heart and spleen(心脾兩虛), the depression of Liver energy(肝氣鬱結), and attack of blended wetness and heat to the lower wanner(濕熱下注). 2. The theraphics of impotence in oriental medicine are warming and strenghthening Kidney. softness of Liver energy, tonifying the Kidney to relieve mental strain, clear away the wetness-heat, and infairment of Heart and Spleen. 3. The prescriptions of impotence are Yugyeyum, Gyibitang, Soyosan, Sunjitang, and Yongdamsagantang. 4. In the western medicine, psycotherapy, medical therapy and surgical therapy are the major way to treat impotence.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.3
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• pp.185-191
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• 2019

During the modern battlefields of multi-batches flight formation attack situation, it is an essential task for a commander to make a proper fire distribution of air defense missile launch platforms for threat targets with effectively and quickly. Pan et al. try to solve this problem using genetic algorithm, but they are fails. This paper gets the initial feasible solution using high threat target first destroying strategy only use 75% available fire of each missile launch platform. Then, the assigned missile is moving to another target in the case of decreasing total threat. As a result of experiment, while the proposed algorithm is polynomial-time complexity greedy algorithm but this can be improve the solution than genetic algorithm.

• Journal of the Korea Concrete Institute
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• v.29 no.3
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• pp.237-248
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• 2017

Frequent terror or military attack by explosion, impact, fire accidents have occurred recently. These attacks and incidents raised public concerns and anxiety of potential terrorist attacks on important infrastructures. However, structural behavioral researches on prestressed concrete (PSC) infrastructures such as Prestressed Concrete Containment Vessel (PCCV) and Liquefied Natural Gas (LNG) storage tanks under extreme loading are significantly lacking at this time. Also, researches on possible secondary fire scenarios after terror and bomb explosion has not been performed yet. Therefore, a study on PSC structural behavior from an blast-induced fire scenario was undertaken. To evaluate the blast-fire combined resistance capacity and its protective performance of bi-directional unbonded PSC member, blast-fire tests were carried out on $1,400mm{\times}1,000mm{\times}300mm$ PSC specimens. Blast loading tests were performed by the detonation of 25 kg ANFO explosive charge at 1.0 m standoff distance. Also, fire and blast-fire combined loading were tested using RABT fire loading curve. The test results are discussed in detail in the paper. The results can be used as basic research references for related research areas, which include protective design simulation under blast-fire combined loading.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.299-304
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• 2023

Recently, drones have been used as a major means of attack drones in major wars around the world, and it seems likely that they will evolve into game changers in the future. Recently, drones have been used as a major means of attack drones in major wars around the world, and it seems likely that they will evolve into game changers in the future. In the major wars of the 21century, attack drones are used for precision fire-guided or self-destruct attacks, For the purpose of cognitive warfare, its territory is expanding not only to land and air, but also to sea and water. These attack drones will perform multi-domain operations, and for this purpose, the level of autonomy will be improved and High-Low Mix We will continue to develop by strengthening concept-based scalability. North Korea has also been making considerable efforts to operate attack drones for a long time, and activities such as third-country-level self-explosive drones, artificial intelligence-based clustered self-explosive drones, and self-destructive stealth unmanned semi-submersible are expected. In addition to North Korea's provocations and attacks, it is hoped that there will be a need for active follow-up research on our military's countermeasures and utilization plans.