• Title/Summary/Keyword: Fire frequency

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Design of a Nature-inspired Wideband Sprout-leaf Antenna (자연모사 기반 광대역 새싹 안테나 설계)

  • Woo, Dongsik;Bae, Sunghyun
    • Journal of IKEEE
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    • v.24 no.2
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    • pp.536-542
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    • 2020
  • This paper presents a nature-inspired wideband sprout-leaf shaped antenna with end-fire radiation pattern. A sprout-leaf shape angled-radiator was designed for wide beamwidth radiation patterns for motion detection sensors. An extended and truncated ground plane was used as a reflector for end-fire radiation patterns. To feed the balanced radiator, a broadband microstrip (MS) to coplanar stripline (CPS) balun was utilized with excellent amplitude and phase balance. The proposed antenna demonstrates wide frequency bandwidth from 8.5 to 14.5 GHz with wide beamwidth and the radiation efficiency of 90%. The measured gain is from 4 to 5 dBi and front-to-back ratio was 10 to 20 dB. It has been shown that the proposed antenna can be used for imaging sensors, phased array systems, and radars that require a wide bandwidth and a directional radiation pattern.

APPLICATION OF 3D TERRAIN MODEL FOR INDUSTRY DISASTER ASSESSMENT

  • Kim, Hyung-Seok;Cho, Hyoung-Ki;Chang, Eun-Mi;Kim, In-Hyun;Kim, In-Won
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.3-5
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    • 2008
  • An increase in oil and gas plants caused by development of process industry have brought into the increase in use of flammable and toxic materials in the complex process under high temperature and pressure. There is always possibility of fire and explosion of dangerous chemicals, which exist as raw materials, intermediates, and finished goods whether used or stored in the industrial plants. Since there is the need of efforts on disaster damage reduction or mitigation process, we have been conducting a research to relate explosion model on the background of real 3D terrain model. By predicting the extent of damage caused by recent disasters, we will be able to improve efficiency of recovery and, sure, to take preventive measure and emergency counterplan in response to unprepared disaster. For disaster damage prediction, it is general to conduct quantitative risk assessment, using engineering model for environmental description of the target area. There are different engineering models, according to type of disaster, to be used for industry disaster such as UVCE (Unconfined Vapour Cloud Explosion), BLEVE (Boiling Liquid Evaporation Vapour Explosion), Fireball and so on, among them, we estimate explosion damage through UVCE model which is used in the event of explosion of high frequency and severe damage. When flammable gas in a tank is released to the air, firing it brings about explosion, then we can assess the effect of explosion. As 3D terrain information data is utilized to predict and estimate the extent of damage for each human and material. 3D terrain data with synthetic environment (SEDRIS) gives us more accurate damage prediction for industrial disaster and this research will show appropriate prediction results.

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Design of wideband microstrip monopole slot antenna (광대역 마이크로스트립 모노폴 슬롯안테나의 설계)

  • Lee, Young-Soon;Cho, Yun-Ki
    • Journal of Advanced Navigation Technology
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    • v.16 no.5
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    • pp.766-772
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    • 2012
  • In the present study, wideband microstrip monopole slot antennas which can be applied to the RF4CE Zigbee remote controller are designed. First I-shaped monopole slot antenna which has ${\lambda}g/4$ length at 2.45GHz is designed. In particular, a conducting via is used to connect the microstrip feed line and the ground plane surrounded with the etched slot for the bandwidth improvement. In order to reduce the antenna size, it is changed into L-shaped and T-shaped monopole slot antennas for which improve results of antenna performance are observed. In case of T-shaped monopole slot antenna, impedance bandwidth(VSWR<2) is about 3.32GHz, and also its radiation efficiency and gain is more than 90% and 2.1dBi respectively at whole operating frequency range. In particular, all of proposed monopole slot antennas have the end-fire radiations which has a maximum radiation power toward direction of open ends of monopole slots.

Structural Response of Offshore Plants to Risk-Based Blast Load

  • Heo, YeongAe
    • Architectural research
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    • v.15 no.3
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    • pp.151-158
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    • 2013
  • Offshore oil and gas process plants are exposed to hazardous accidents such as explosion and fire, so that the structural components should resist such accidental loads. Given the possibilities of thousands of different scenarios for the occurrence of an accidental hazard, the best way to predict a reasonable size of a specific accidental load would be the employment of a probabilistic approach. Having the fact that a specific procedure for probabilistic accidental hazard analysis has not yet been established especially for explosion and fire hazards, it is widely accepted that engineers usually take simple and conservative figures in assuming uncertainties inherent in the procedure, resulting either in underestimation or more likely in overestimation in the topside structural design for offshore plants. The variation in the results of a probabilistic approach is determined by the assumptions accepted in the procedures of explosion probability computation, explosion analysis, and structural analysis. A design overpressure load for a sample offshore plant is determined according to the proposed probabilistic approach in this study. CFD analysis results using a Flame Acceleration Simulator, FLACS_v9.1, are utilized to create an overpressure hazard curve. Moreover, the negative impulse and frequency contents of a blast wave are considerably influencing structural responses, but those are completely ignored in a widely used triangular form of blast wave. An idealistic blast wave profile deploying both negative and positive pulses is proposed in this study. A topside process module and piperack with blast wall are 3D FE modeled for structural analysis using LS-DYNA. Three different types of blast wave profiles are applied, two of typical triangular forms having different impulse and the proposed load profile. In conclusion, it is found that a typical triangular blast load leads to overestimation in structural design.

A Study on Job Stress and Job Satisfaction of 119 Relief Squads (119 구급대원의 직무스트레스와 직무만족도)

  • Lee, Sung-Hee;Choi, Yeon-Hee
    • Research in Community and Public Health Nursing
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    • v.17 no.4
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    • pp.521-529
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    • 2006
  • Purpose: This study was to measure the degree of job stress and job satisfaction and the relationship between job stress and job satisfaction of 119 relief squads. Methods: The subjects were 170 members of 119 relief squads in the Fire Department of D City, and data were collected from 1 April to 20 April, 2006 through a survey using a questionnaire composed of questions on general characteristics (11 items), job stress (6 items) and job satisfaction (20 items). Collected data were analyzed through frequency, percentage, t-test, ANOVA and Pearson's correlation using the SPSS program. Results: The average item score for job stress was 2.77. Role sharing with peers was highest as 3.05. There were significant differences in the degree of job stress according to religion, working period and applying motive. The average item score for job satisfaction was 2.93. Group conflict was highest as 3.18. There were significant difference in the degree of job satisfaction according to religion, working period and applying motive. There were significant differences in the negative correlation between role-sharing with peers among the job stress factors and decision-making factor (r=.53), group conflict factor (r=.58), role implementation factor (r=.63) and personal social-culture factor (r=.53) among the job satisfaction factors. Also, there were significant differences in the negative correlation between co-workers among the job stress factors and decision-making factor (r=.607), group conflict factor (r=.51) and personal social-culture factor (r=.45) among the job satisfaction factors. Conclusion: It is important to develop various methods of job stress management to increase job satisfaction in 119 relief squads.

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A Study on the Development of the Curriculum for EMT Continuing Education (응급구조사 보수교육의 교과과정 개발에 관한 연구)

  • 최용철;이창섭;왕순주
    • Fire Science and Engineering
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    • v.17 no.1
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    • pp.46-61
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    • 2003
  • As EMTs (Emergency Medical Technician), they will be required to attend a certain number of hours of continuing education each year to maintain, update, and expand their knowledge and skills. Continuing Education courses must be designed to keep up with the rapid changes in medicine. But, there are no standard CE curricula including reasonable subject matters and contents in this country, This paper analyzed many different CE curricula in advanced countries and examined the survey for educational needs to develop a standard CE curriculum. The following alternative plans to improve was proposed : (a) The subject matters should be enlarged and the contents subdivided. (b) The reasonable school hours of each subject matter should be allocated. (c) The applicable curriculum to the field affairs should be designed. (d) The frequency of CE should increased to expand an educational chance. (e) The educational circumstances should be improved, the educational outcomes be evaluated and flowed back. On the basis of the above alternatives plans, this paper proposed a model for the standard CE curriculum.

Comparison of Video Laryngoscope and Direct Laryngoscope on Rapidity and Accuracy in Tracheal Intubation by Paramedic (1급 응급구조사의 비디오후두경 기관삽관과 직접후두경 기관삽관의 신속성 및 정확도 비교)

  • Sim, Gyu-Sik
    • The Korean Journal of Emergency Medical Services
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    • v.14 no.1
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    • pp.5-18
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    • 2010
  • Objective : This study compares Video laryngoscope and Direct laryngoscope in tracheal Intubation on rapidity and accuracy by paramedic and aims to improve efficiency of airway management and survival rate in pre-hospital treatment for the patients with severe trauma, cardiac arrest or dyspnea caused by acute diseases. Methods : 60 paramedics were recruited from 13 fire stations located in C province. With the consent of the paramedics, likelihood ratio test was carried out and they were divided into two different groups; DL group (30) and GVL group (30). Regarding intubation conditions, difficult airway grade I, grade II and grade III as well as sniffing position and neutral position were examined. This study also compared between ambulance in motion and in stand still. Frequency, average and standard deviation were analyzed with statistics program, SPSS WIN 17.0 and repeated measure design was introduced to examine inter-relations between position, grade and groups. Results : Intubation was performed more rapidly in neutral position and GVL than in sniffing position and DL(F = 15.260, p = .000). Rapidity value was better with grade I and grade II than grade III and better with GVL than DL(F = 32.629, p = .000). Accuracy value was higher with neutral position and GVL than sniffing position and DL(F = 5.008, p = .011). grade III was less accurate than grade I, grade II and GVL was more accurate than DL(F = 10.966, p = .000). Ambulance motion status did not show any statistically significant differences in accuracy and rapidity. Conclusion : Given this study results, neutral position is better for the patient with severe trauma. For a better survival, GVL intubation can be considered since GVL can enhance accuracy as well as rapidity regarding difficult airway. Since there is no significant differences in ambulance motion factors, intubation can be recommended even in moving ambulance for shortening traveling time to a hospital.

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Co-relation between Questionnaire for Buzhongyiqi-Tang and Electrogastrography (보중익기탕 변증설문지와 위전도의 상관성 연구)

  • Kim, Sun-Hyeok;Park, Young-Bae;Park, Young-Jae;Oh, Hwan-Sup
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.13 no.2
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    • pp.34-44
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    • 2009
  • Background : Currently, as a method of standardization of prescription, questionnaire for Buzhongyiqi-Tang[補中益氣湯] was developed, and which is a Objectives : The purpose of this thesis is to testify whether differentiation of Lao Juan Shang[勞倦傷] etiology is relative to mobility of gastric smooth muscle. Methods : The subjects(20 to 65 years old; 14 males, 46 females) were isolated from drinking alcohols for 24 hours before the experiment, and fasted for 8 hours, and measured for electrogastrography(EGG) and they filled out Questionnaire for Buzhongyiqi-Tang. Results : 1. Six factors from the factor analysis of Questionnaire for Buzhongyiqi -Tang were named and classified as Spleen-Qi deficiency syndrome factor [脾虛] (factor 1), Lung-Qi deficiency syndrome factor [肺虛] (factor 2), Working factor [習慣] (factor 3), Yin-Fire factor [陰火] (factor 4), Jung-Qi deficiency syndrome factor [中氣虛] (factor 5), and Stomach-Qi deficiency syndrome factor [胃虛] (factor 6). 2. As for the reliability of Questionnaire for Buzhongyiqi-Tang, we used Cronbach's alpha coefficient. Cronbach's alpha coefficient was 0.772 for the mean of the item-total. 3. Lung-Qi deficiency syndrome factor(factor2) had significant correlation with Bradygastria Time (r=-0.312, p<0.05). 4. Working factor(factor3) had significant correlation with Bradygastria Time (r=-0.329, p<0.05). 5. Yin-Fire factor(factor4) had significant correlation with Power Ratio (r=-0.328, p<0.05). Conclusions : It is shown that Bradygastria Time and Power Ratio tended to decrease against postprandial DP increased and postprandial frequency decreased in normal case.

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A Systematic Review of the Variables Related to Post-Traumatic Stress Disorder in Firefighters (소방공무원의 외상 후 스트레스 장애 관련변인에 관한 체계적 문헌고찰)

  • Kang, Min-Ju;Kim, Young-Hwa;Han, Seung-Woo
    • Fire Science and Engineering
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    • v.33 no.2
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    • pp.164-172
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    • 2019
  • This study examined the Post-Traumatic Stress Disorder (PTSD)-related variables of firefighters through a systematic literature review. Electronic databases were searched, including RISS, National Assembly Library, NDSL, KmBase. The search terms were PTSD, Post-Traumatic Stress, Post-Traumatic Stress Disorder and Firefighter. Eleven studies from 146 references screened were included. All studies were non-experimental and correlational analyses. The positive correlation factors were age, duration of work, traumatic events, frequency of mobilization, number and strength of traumatic events experienced, work burden, coping method, D-type personality, depression, and anger rumination. The negative correlation factors were resilience, social support, self-esteem. To improve the mental health of firefighters in the future, professional intervention programs should be constructed to improve resilience, social support, and self-esteem, which are protective factors of PTSD.

A Study on the Relation between Knowledge and Attitude on Coronavirus Disease-19 (COVID-19) and Infection Control Performance of Paramedic students (응급구조(학)과 대학생의 코로나바이러스감염증-19(COVID-19)에 대한 지식 및 태도와 감염관리 수행도 간의 관련성 연구)

  • Park Dae-Sung;Kim Gap-Seon;Lee Man-Jin;Kim Ye-Rim
    • Journal of Advanced Technology Convergence
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    • v.2 no.3
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    • pp.25-32
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    • 2023
  • This study was conducted to find out the relationship between knowledge and attitudes about COVID-19 and infection control performance among college students in paramedicine. The subjects of the study were 154 university students attending a 3-4 year paramedicine located in Gwangju Metropolitan City, Jeollabuk-do Province, and the collected data were frequency, percentage, sum, average and It was analyzed by standard deviation, t-test, ANOVA(Scheffe), Pearson's Correlation Coefficient, and Multiple Linear Regression. The order of attitude and knowledge about COVID-19 affected the infection control performance of college students in the paramedicine. Therefore, it is necessary to develop and apply regular or non-regular curriculum and multidisciplinary curriculum that can improve knowledge and attitudes about COVID-19 in order to improve the infection control performance of paramedic students.