• Title/Summary/Keyword: Behavior(movement) Characteristics

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Experimental Study on the Soot Formation Behavior of Octane Single Fuel Droplet Under the Constant Volume Combustion Conditions (정적 연소 조건에서 Octane 단일 연료 액적의 매연 생성 거동에 관한 연구)

  • Lim, Young Chan;Suh, Hyun Kyu
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.41 no.6
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    • pp.389-395
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    • 2017
  • This study was performed to provide the information of the soot formation behavior of octane single fuel droplet under the identical combustion conditions. To achieve this, this experimental study provide the results of the soot formation characteristics of octane droplet in accordance with different initial droplet diameter($d_0$), at the same time, experiment was conducted under the same combustion conditions which are 1.0atm of ambient pressure($P_{amb}$), 21% of oxygen concentration($O_2$) and 79% of nitrogen concentration($N_2$). Visualization of octane droplet combustion was performed by visualization system with high speed camera. The results of maximum soot volume fraction($f_{vmax}$) was almost the same under the equivalent ambient conditions regardless of initial droplet diameter. Furthermore, maximum soot volume fraction was showed the higher value in the measuring direction between $135^{\circ}$ and $315^{\circ}$ since the soot-tail is generated during two opposing igniters movement process.

Study on Pullout Behavior of Pipe Anchor (파이프형 앵커의 인발거동에 대한 연구)

  • Bae, Wooseok;Lee, Bongjik;Kwon, Youngcheul;Lee, Jundae
    • Journal of the Korean GEO-environmental Society
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    • v.9 no.1
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    • pp.5-10
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    • 2008
  • In this study, laboratory model test was performed to estimate pullout behavior of pipe type anchor with surface roughness, embedment and diameter. The design of buried pipe anchors in areas of vertical ground movement is governed, in part, by magnitude of the forces imposed on the pipe and displacements at which they are developed. In this paper, uplift resistance and displacement characteristics of pipe anchors caused by ground condition and embedment ratio, surface roughness, pipe diameter through the analysis of pipe anchor model test were compared and analyzed. The test results of the buried pipe showed that as the relative density increases, ultimate uplift resistance increase in 20%. When pipe anchor is failed with the relative density of the ground, the change of surface roughness, it was shown that the deformation increases as the ratio of penetration increases from 2 to 8 in five times approximately. And most anchor-based theories overestimate the breakout factor.

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A Numerical Study of Flame Spread of A Surface Forest Fire (지표화 산불의 화염전파 수치해석)

  • Kim, Dong-Hyun;Lee, Myung-Bo;Kim, Kwang-Il
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.80-83
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    • 2008
  • The characteristics of the spread of a forest fire are generally related to the attributes of combustibles, geographical features, and meteorological conditions, such as wind conditions. The most common methodology used to create a prediction model for the spread of forest fires, based on the numerical analysis of the development stages of a forest fire, is an analysis of heat energy transmission by the stage of heat transmission. When a forest fire breaks out, the analysis of the transmission velocity of heat energy is quantifiable by the spread velocity of flame movement through a physical and chemical analysis at every stage of the fire development from flame production and heat transmission to its termination. In this study, the formula used for the 1-dimensional surface forest fire behavior prediction model, derived from a numerical analysis of the surface flame spread rate of solid combustibles, is introduced. The formula for the 1-dimensional surface forest fire behavior prediction model is the estimated equation of the flame spread velocity, depending on the condition of wind velocity on the ground. Experimental and theoretical equations on flame duration, flame height, flame temperature, ignition temperature of surface fuels, etc., has been applied to the device of this formula. As a result of a comparison between the ROS(rate of spread) from this formula and ROSs from various equations of other models or experimental values, a trend suggesting an increasing curved line of the exponent function under 3m/s or less wind velocity condition was identified. As a result of a comparison between experimental values and numerically analyzed values for fallen pine tree leaves, the flame spread velocity reveals has a error of less than 20%.

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Dynamic Response and Reinforcement of the Railway Plate Girder Bridges (무도상 철도판형교의 동적응답특성 및 보강방안)

  • Hwang, Won Sup;Cho, Eun Sang;Oh, Ji Taek;Kim, Hyun Min
    • Journal of Korean Society of Steel Construction
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    • v.19 no.3
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    • pp.281-290
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    • 2007
  • In this paper, the dynamic behavior of a 12m plate girder railway bridge is analyzed using the commercial FEM program. A time history load is applied to a standard train load via the shape function ofthe beam element. In addition, lateral behavior characteristics were simulated using the Klingel sine movement. A feasibility study of the FEM program and an analysis were performed by comparing the displacement and the acceleration, from the experimental data and the results of the FEM analysis. the time history of the lateral and vertical displacements are reflected in the experimental results. Six kinds of reinforcements were studied from the effects of the displacement and the acceleration. The RF-1 model that was applied to the upper lateral bracing system, and the RF-3 model that reinforced the plate, turned out to be the most effective reinforcement methods with respect to weight limits and construction simplification.

A Gap-acceptance Model Considering Driver's Propensity at Uncontrolled Intersection (운전자 특성 등을 고려한 무통제교차로의 간격수락 모델)

  • Jang, Jeong-Ah;Lee, Jung-Woo;Choi, Kee-Choo
    • Journal of Korean Society of Transportation
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    • v.26 no.6
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    • pp.71-80
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    • 2008
  • Typically uncontrolled intersections are characterized by the absence of signal, stop and yield sign, and by very light traffic volume. In this study, a gap acceptance model for such uncontrolled intersections has been modeled. The motivation is to identify the behavior of drivers so that the traffic flow phenomena can be easily understood. For this, actual traffic survey was accomplished at intersections in Suwon and the data have been fed into modeling process. The logit model was used and the results showed that total delay experienced by drivers, turning right movement, age, sex, and the existence of passenger affected gap acceptance. For example, male drivers, with experiencing longer delay and having passenger(s) with them, accepted shorter gaps. These identified characteristics regarding gap acceptance could be used for facility design and/or safety oriented traffic information dissemination near uncontrolled intersections.

Design of YOLO-based Removable System for Pet Monitoring (반려동물 모니터링을 위한 YOLO 기반의 이동식 시스템 설계)

  • Lee, Min-Hye;Kang, Jun-Young;Lim, Soon-Ja
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.1
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    • pp.22-27
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    • 2020
  • Recently, as the number of households raising pets increases due to the increase of single households, there is a need for a system for monitoring the status or behavior of pets. There are regional limitations in the monitoring of pets using domestic CCTVs, which requires a large number of CCTVs or restricts the behavior of pets. In this paper, we propose a mobile system for detecting and tracking cats using deep learning to solve the regional limitations of pet monitoring. We use YOLO (You Look Only Once), an object detection neural network model, to learn the characteristics of pets and apply them to Raspberry Pi to track objects detected in an image. We have designed a mobile monitoring system that connects Raspberry Pi and a laptop via wireless LAN and can check the movement and condition of cats in real time.

A Study on the Evacuation Performance Analysis Model Considering Clustering Types at the Fire Event in Geriatric Hospital (노인 요양병원에서 화재 시 군집유형에 따른 피난 성능 분석 모델에 관한 연구)

  • Kim, Mijung;Kweon, Jihoon
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.28 no.1
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    • pp.63-74
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    • 2022
  • Purpose: The purpose of this study is to present an evacuation performance analysis model that can derive vulnerable evacuation spaces with considering the movement behavior as per the elderly groups in the event of a fire in a geriatric hospital. Methods: The evacuation characteristics of geriatric hospital users were investigated through the review of precedent studies. First, the occupant conditions and the evacuation scenario were set to analyze a study target hospital. Then, the evacuation simulation was carried out considering the group types and the density of each group. Finally, an evacuation performance analysis model according to the group type was presented based on the simulation results. Results: The results of this study are as follows: (1) The evacuation performance according to the group type is to be clarified through the suggested study model. (2) It is necessary to secure a ramp or an emergency elevator to distribute the evacuation personnel at the design stage because congestion occurs due to collisions between evacuees on the stairs and delays the evacuation time. (3) It is necessary to consider the evacuation stairs and openings of sufficient size by analyzing the frequency of congestion occurrence and the escape routes of occupants in advance to identify the space where the evacuation flow overlaps. Implications: It is expected that the study result is to be used as primary data for studies that consider the elderly and clustering evacuation behavior in the event of a fire in a geriatric hospital.

Health Behaviors Before and After the Implementation of a Health Community Organization: Gangwon's Health-Plus Community Program

  • Joon-Hyeong Kim;Nam-Jun Kim;Soo-Hyeong Kim;Woong-Sub Park
    • Journal of Preventive Medicine and Public Health
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    • v.56 no.6
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    • pp.487-494
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    • 2023
  • Objectives: Community organization is a resident-led movement aimed at creating fundamental social changes in the community by resolving its problems through the organized power of its residents. This study evaluated the effectiveness of health community organization (HCO), Gangwon's Health-Plus community program, implemented from 2013 to 2019 on residents' health behaviors. Methods: This study had a before-and-after design using 2011-2019 Korea Community Health Survey data. To compare the 3-year periods before and after HCO implementation, the study targeted areas where the HCO had been implemented for 4 years or longer. Therefore, a total of 4512 individuals from 11 areas with HCO start years from 2013 to 2016 were included. Complex sample multi-logistic regression analysis adjusting for demographic characteristics (sex, age, residential area, income level, education level, and HCO start year) was conducted. Results: HCO implementation was associated with decreased current smoking (adjusted odds ratio [aOR], 0.73; 95% confidence interval [CI], 0.57 to 0.95) and subjective stress recognition (aOR, 0.79; 95% CI, 0.64 to 0.97). Additionally, the HCO was associated with increased walking exercise practice (aOR, 1.39; 95% CI, 1.13 to 1.71), and attempts to control weight (aOR, 1.36; 95% CI, 1.12 to 1.64). No significant negative changes were observed in other health behavior variables. Conclusions: The HCO seems to have contributed to improving community health indicators. In the future, a follow-up study that analyzes only the effectiveness of the HCO through structured quasi-experimental studies will be needed.

The Characteristics of New Age Consciousness in the Popular Culture - Focus on 'Avatar' (대중문화에 나타난 뉴에이지 사상의 특징 -아바타를 중심으로-)

  • Lee, Jun-Soo
    • Cartoon and Animation Studies
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    • s.41
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    • pp.1-29
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    • 2015
  • This paper aims at studying how to express and be used the characteristics of New age consciousness in the popular culture. New age consciousness is used interchangeably with new age movement. The philosophy of new age is based on humanism, which the infinite potential power of human can change the human himself and the earth forward to be shown the new age of peace, hope and love in an instant. This consciousness is based on the Western secret art and Eastern consciousness against the Christianity and has begun to develop in the alternative religion influenced by Postmodernism and Counterculture movement on 1970's which is against the corruption of American society on 1960's. However, new age consciousness has tried to change to a social movement for the culture, the peace, the happiness of mankind and the healing society rather than a religion idea because of the limitation of the theory itself. Nevertheless, the new age culture contains the characteristics of the religion, and the characteristics has been easily borrowed to the mess media and infiltrated to us. In a broad sense, the religion includes both own religion beliefs and behavior and the social movements and tendencies about the established religion which pursues the holy and the highest value. The religion is valued as a complex culture phenomenon, which the religion presents the right direction and the meaning of life as well as contributes to the maintenance of social order and the social unification. For this reason, the religion and the culture have a deep relationship between mess media and needs to be captured and listen to religious longing lurking deep within the human consciousness in order to give the audience impressed and fun. In the study, the characteristics of New age such as reincarnation, illusion, meditation, monism and pantheism is analyzed for what affects students studying mess media and the popular culture. And then the study is analyzed the characteristics of new age consciousness in the animation through 'Avatar'. This study shed new light on the influence of religion which is ideological identity of popular culture, and I expect to be a little help to have the insight to examine the mess media with a various angles.

A Study on the Hydraulic Characteristics for River Bed Revetments using Mattress (하상보호용 매트리스의 수리학적 특성 연구)

  • Bae, Sang-Su;Heo, Chang-Hwan;Ji, Hong-Gi;Lee, Sun-Tak
    • Journal of Korea Water Resources Association
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    • v.35 no.1
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    • pp.77-90
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    • 2002
  • The condition of initial movement for the river bed revetment using rip rap is a limit condition beyond which the lining is progressively destroyed as the separate elements are removed by the flow. In the case of the river bed revetment using mattress, however, after the initial movement the containment offered by the mesh remains. A new situation of equilibrium with a deformed river bed revetment using mattress is obtained, allowing it to withstand more severe conditions without compromising the resistance and without further bed deformation. Shield's coefficient for the river bed revetment using mattress is twice the value of that for the river bed revetment using rip rap. This means that with the same hydraulic behavior conditions, the average dimension of the rocks to be used in the river bed revetment using mattress is half that of the river bed revetment using rip rap rock. When the same size rocks are used the allowable velocity for the river bed revetment using mattress is more than twice, even as much as 3 or 4 times that for the river bed revetment using rip rap.