• Journal of Korean Society of Transportation
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• v.34 no.2
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• pp.146-157
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• 2016

The objective of this study is to actualize a statistical model of the 3-detector simplification model, which was proposed to detect outbreak situations by Daganzo in 1997 and to verify the statistical appropriacy thereof. This study presents the calculation process of the 3-detector simplification model and realizes the process using a statistics program. Firstly, the model was applied using data on detector of the main highways on which there is no entrances or exits. Moreover, in order to statistically verify the 3-detector simplification model, accumulative traffics for 30 seconds period, which reflects the dynamic changes of traffics due to shock wave, were estimated for outbreak traffics and steady flow, and the error of acquired data was statistically compared with that of the actual accumulative traffics. As a result, the error ratio between steady and incident cumulative flows has reached its maximum after 2-3 hours from an accident. Moreover, the incident traffic flows by accidents and the stade flows are heterogeneous in terms of their dispersion and means.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.538-555
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• 2000

The purpose of this study, in which 573 students from 2 high schools in Kang Nung city participated was to identify the attitude and experience of sexual harassment. This information will provide useful data, and promote a more systematic sexual harassment education program. The subjects of this study were 278 male students and 295 female students. The data was collected from September 25 to October 6. 2000. The data was analyzed using the statistical Computer package. SPSS to manipulate the data along with frequency, percentage, and mean t-test. The results from this study were summarized as follows. 1. The results from this comparison between two groups were significant in their attitude on sexual harassment(t=-2.26. p=0.024). Female students had higher scores than male students. 2. As a cause of sexual harassment. 'A man's misjudgement regarding a women as sexual objects(n=130: 22.7%)'. 'Patriarchal system of unequal distribution of power and status between the sexes(n=105: 18.3%)'. 'The effect of sexual stimulatives. (pornography. pornovideo. TV program ect.)(n=89: 15.5%)'. 3. As a countermeasure for prevention, 'Punishment, law and regulation of the sexual harasser(n = 151; 26.4%)', 'A preventive education of sexual harassment in adolescence (n = 125: 21.8%)'. 'Reformation of gender inequality and sex discrimination in the socio-structure(n=76; 13.3%)'. 4. Out of 573 students who participated in this study, 209(36.5%) students reported experiencing an incident of sexual harassment. For 278 males who participated in this study, 88(31.7%) had experienced an incident of sexual harassment. For the 295 females who participated in this study, 121(41.0%) had experienced an incident of sexual harassment. The type of sexual harassment is reported physical sexual harassment(n = 248: 40.5%), verbal sexual harassment(n = 226; 36.7%), and visual sexual harassment(n=139: 22.6%). 5. Their age in which they had experienced harassment was usually 'after 16 years of age(n=122: 58.4%)'. The age of harassers were mostly teenagers(n=112; 53.6%). The relationship to the with sexual harasser was a stranger (n=85; 40.7%), or a friend(n=78: 37.3%). After the incident of sexual harassment occurred, some students informed friends (n=114: 54.5%), 63(30.1%) told no one. Male students' feelings after the experienced harassment ranged from: 'be interesting', 'be pleasant'. Female students' feelings after the experienced harassment ranged from; 'be surprised', 'get a shock', 'fear', 'shame'.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.5
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• pp.1-11
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• 2014

Sympathetic detonation (SD) of high explosives occurs when a detonating donor initiates neighboring acceptors. The present study focuses on the hydrodynamic simulation of one-on-one sympathetic detonation of 155 mm charge filled with PBXN-109. Both unbuffered and buffered SD configurations are performed while changing the distance between each charge, in order to investigate the detonation sensitivity to a donor initiation. The cause of a SD is by a shock impact for the unbuffered case at a close range, while at a distant range, blast fragment penetration is the primary cause. The buffers can reduce the incident sensitivity to a SD by reducing the strengths of shock wave and impinging fragments.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.419-426
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• 2008

As pulse detonation engine(PDE) does not need compression mechanisms such as compressors because self-sustained detonation waves are able to compress propellant gases by their incident shock waves, the PDE can have a simple straight-tube structure. In this study, we propose an autonomous driving valve system of the PDE, which fill premixed gases into the PDE tubes at high frequency with high mass flow rate. The proposed valve is composed of only three parts: a piston, a cylinder, and a spring. This valve system can produce intermittent flow at high mass flow rate, and also can keep stable reciprocal motion by using the propellant-gas enthalpy. When the cylinder content product is assumed to be constant, experimental results of the mass flow rate were approximately equal to the calculation model. We confirmed the autonomous driving valve performance by experiments, and concluded that this extremely simple valve with no electrical power and controller can be used as the PDE propellant supply system.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.267-273
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• 2012

Solar reforming of methane with CO2 was successfully tested with a direct irradiated absorber on a parabolic dish capable of 5kWth solar power. And the new type of double-layer absorber-the front layer, porous metal foam which absorbs the radiation and transfers the heat from material to gas, and the back layer, catalytically-activated metal foam-was prepared, and its activity was tested by using electric furnace. Ni was applied as the active metal on the gamma-Al2O3 coated Ni metal foam for the preparation of the catalytically-activated metal foam layer. Compared to conventional direct irradiation of the catalytically activated metal foam absorber, this new type of double layer absorber is found to exhibit a superior reaction and thermal storage performance at the fluctuating incident solar radiation. In addition, unlike direct irradiation of the foam absorber, double layer absorber has better thermal resistance, which prevents the emergence of cracks caused by mechanical or thermal shock. The total solar power absorbed reached up to 3.25kW and the maximum CH4 conversion was almost 59%.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.3
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• pp.481-490
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• 2010

The shock of melamine-contained food has been known with the incident of hospitalization or death of infants at the age of 11-month old in China. The purpose of this study was to examine consumers' risk perception, attitude and purchase behavior of melamine-contained food which recently came to the fore as a social issue, focusing on the relationship between consumers' attitude and purchase behavior based on physical risk, social risk, psychological risk, financial risk, consumers' attitude and purchase behavior. Study findings are as follows. First, the four factors of risk perception of melamine-contained food were significantly different by consumers. Consumers regarded social risk as most significant and it was followed by financial risk and psychological risk. And they regarded physical risk as most insignificant. Second, as for the difference of risk perception by demographic features, such factors as gender, age, marital status and schooling had no statistically significant influence. Third, the potential risk of melamine-contained food had a negative influence upon consumers' attitude and purchase behavior. In addition, consumers' attitude and purchase behavior were decided by perceived risks. This finding implies that consumers' attitude can accompany with negative or positive behavior and consumers' behavior can be related to social, financial and physical risks. Because the risk perception of melamine-contained food can cause consumers' distrust about all kinds of food in general, domestic manufacturers of milk product-contained confectionery and food can be harmed. In order to overcome this problem and make consumers purchase all the milk products and milk-contained food without fear, governmental agencies must reestablish systems with which the safety of imported raw materials and its processing can be insured and manufactures must improve the quality of products in a diverse and discriminative manner. This study seems to be meaningful in that it examined consumers' risk perception of melamine-contained food, a current social issue, and then looked into the influence of risk perception upon consumers" attitude and behavior, thus presenting the strategy of reestablishing the system of relationship between consumers and business entities in a desirable manner.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.80-86
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• 2011

Solar reforming of methane with CO2 was successfully tested with a direct irradiated absorber on a parabolic dish capable of 5kWth solar power. And the new type of double-layer absorber - the front layer, porous metal foam which absorbs the radiation and transfers the heat from material to gas, and the back layer, catalytically-activated metal foam - was prepared, and its activity was tested by using electric furnace. Ni was applied as the active metal on the gamma-Al2O3 coated Ni metal foam for the preparation of the catalytically-activated metal foam layer. Compared to conventional direct irradiation of the catalytically activated metal foam absorber, this new type of double layer absorber is found to exhibit a superior reaction and thermal storage performance at the fluctuating incident solar radiation. In addition, unlike direct irradiation of the foam absorber, double layer absorber has better thermal resistance, which prevents the emergence of cracks caused by mechanical or thermal shock. The total solar power absorbed reached up to 3.25kW and the maximum CH4 conversion was almost 59%.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.1
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• pp.39-48
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• 2022

Purpose : This study aimed to determine the experiences of the disaster response team 9 participants who participated in the disaster after the fire incident occurred in Jecheon Sports Center and their meaning and essence. Methods : Nine disaster response teams were the subjects of the study, and Individual in-depth interviews were conducted. Data were collected online between January 6 and April 30, 2021, from the software Zoom^TM. This study was conducted as a qualitative study by applying Giorgi's phenomenological experiential research method, which has an advantage in revealing the essential structure and meaning of experience. Results : Three major themes were derived from the study results: the stimulus through unfamiliar experiences, the grievances due to work environment and regional characteristics, and dullness resulting from hiding and enduring. The following 17 sub-themes were identified: learning through unfamiliar experiences, frustration due to unexpected circumstances, shock from unfamiliar experiences, doing my best in the present, confidence due to increased experience, disunified system, intervention of various interests, the atmosphere that puts responsibility on others, inactive help, unforgettable regional characteristics, working without time to settle, tolerating it in my own way, memories left in the unconsciousness, sudden suffering from memories that come to mind, movement in anxiety and tension, dullness, work with colleagues in the same situation. Conclusion : This study is meaningful in that it attempted to provide basic data in preparing a long-term strategy for effective policy direction and institutional protection based on the systematic mental health management of the disaster response team. Additionally, this study's results can be used as primary data for future research among Disaster Response Team.

• Journal of Trauma and Injury
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• v.29 no.4
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• pp.204-208
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• 2016

For an orthopaedic surgeon, the critical decisions to either amputate or salvage a limb with severe crushing injury with progressive ischemic change due to arterial rupture or occlusion can become a clinical dilemma at the Emergency Department (ED). And reperfusion injury is one of the fetal complications after vascular reconstruction. The authors present a case which was able to save patient's life by rapid vessel ligation at bedside to prevent severe reperfusion injury. A 43-year-old male patient with no pre-existing medical conditions was transported by helicopter to Level I trauma center from incident scene. Initial result of extended focused assessment with sonography for trauma (eFAST) was negative. The trauma series X-rays at the trauma bay of ED showed a multiple contiguous rib fractures with hemothorax and his pelvic radiograph revealed a complex pelvic trauma of an Anterior Posterior Compression (APC) Type II. Lower extremity computed tomography showed a discontinuity in common femoral artery at the fracture site and no distal run off. Surgical finding revealed a complete rupture of common femoral artery and vein around the fracture site. But due to the age aspect of the patient, the operating team decided a vascular repair rather than amputation even if the anticipated reperfusion time was 7 hours from the onset of trauma. Only two hours after the reperfusion, the patient was in a state of shock when his arterial blood gas analysis (ABGA) showed a drop of pH from 7.32 to 7.18. An imminent bedside procedure of aseptic opening the surgical site and clamping the anastomosis site was taken place rather than undergoing a surgery of amputation because of ultimately unstable vital sign. The authors would like to emphasize the importance of rapid decision making and prompt vessel ligation which supply blood flow to the ischemic limb to increase the survival rate in case of profound reperfusion injury.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.161-168
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• 2009

The ubiquitous transportation system environments make it possible to collect each vehicle's position and velocity data and to perform more sophisticated traffic flow management at individual vehicle or platoon level through V2V and V2I communication. It is necessary to develop a new traffic management paradigm to take advantage of the ubiquitous transportation system environments. This paper proposed a preventive congestion management algorithm for uninterrupted flow, whose goal is to minimize the incident potential and maximize the productivity by maintaining traffic flow stability. The algorithm includes the following steps: Processing the raw data to produce the 3-dimension speed/flow/density profile and to produce the platoon profile and the shock wave profile, Determining the traffic state and the flow stability based on the processed data, Deciding the desirable speed the according the traffic flow state, and finally Providing the desirable speed information. It remains as further work to perform field experiments and calibrate the algorithm parameters.