• Title/Summary/Keyword: hot environment

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Characteristics of VOCs Emission Exhausted from Cold and Hot Start Vehicles (자동차 cold start와 hot start에 의한 VOCs 배출특성)

  • 유영숙;엄명도;류정호;김종춘;임철수;김선문;선우영
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.11a
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    • pp.233-234
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    • 2002
  • 도시대기오염의 주요 배출원으로 알려진 자동차에서 배출되는 VOCs는 인체에 유해할 뿐만 아니라 대기 중에서 질소산화물(NOx)과 함에 광화학반응을 통한 오존 둥 2차 오염물질인 광화학산화물을 형성하는 전구물질로 작용하기 때문에 환경학적, 보건학적으로 매우 큰 영향을 미친다. 이러한 자동차 배출 VOCs가 오존생성에 미치는 영향에 대한 연구는 갈수록 증가하고 있는 대기중 오존 농도 심화현상의 규명과 대기질 개선을 위한 기초자료로서 매우 그 필요성이 더해가고 있다. (중략)

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Development of On -Line Work Roll Surface Monitoring System At Hot Strip Mill

  • Moon, Bae-Ho
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.53.4-53
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    • 2001
  • This paper described about the system which can be inspect work roll surface for deciding a milling schedule and roll changing at hot strip mill in POSCO. Developed system consists of CCD camera, Xenon lamp with fiber bundle and mechanical control part. The water probe build up water pole between head of probe and roll surface to acquisite a good image from a work roll surface under the bad environment with steam, cooling water and high temperature. This system is possible to monitor a work roll surface of about 12${\times}$9mm. We have shown the validation of the developed system which can monitor the evolution of degradation on work roll surface.

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Hydration Heat Characteristics of Concrete with Synthetic Resin Form in Hot Weather Circumstance (서중환경 시 합성수지 거푸집 적용 콘크리트 수화열 특성)

  • Nam, Kyung-Yong;Kim, Seong-Deok;Choi, Suk;Yoo, Jung-Il
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.11a
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    • pp.129-130
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    • 2020
  • This paper attempted to examine the characteristics of heat of hydration and calorific value of concrete according to the formwork material in Hot weather environment. As a result of the experiment, it was found that there were no problems such as temperature cracking and delay in hydration reaction when a synthetic resin form was used.

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Investigating risk of overheating for school buildings under extreme hot weather conditions

  • Lykartsis, Athanasios;B-Jahromi, Ali;Mylona, Anastasia
    • Advances in Energy Research
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    • v.5 no.4
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    • pp.277-287
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    • 2017
  • This study examines the risk of overheating of a school building, under extreme hot weather conditions, in 14 locations in the United Kingdom using the overheating criteria defined in Building Bulletin 101 (BB101). The building was modelled as naturally ventilated, mechanically ventilated and in mixed mode and was simulated both for the current and the projected weather conditions of the 2050s. Under the current weather conditions, results of the simulations show that when naturally ventilated, the school building fulfils the BB101 criteria only in the areas of Edinburgh and Glasgow. In the simulations of the building as mechanically ventilated and in mixed mode, mechanical cooling was provided in order for the building to comply with the overheating criteria. A comparison of the required cooling loads between the two scenarios shows that application of mixed mode ventilation results in less cooling loads.

A Study on the High Temperature Filtration Performance Test of Low Density Ceramic Filters (저밀도 세라믹 필터의 고온 여과 성능시험에 관한 연구)

  • 이동섭;홍민선;최종인
    • Journal of Korean Society for Atmospheric Environment
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    • v.17 no.1
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    • pp.75-84
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    • 2001
  • Hot gas filtration method via using ceramic filters is an evolving technology applicable to numerous industrial and air pollution control processes. Alumino silicate, organic and inorganic binders were the major raw materials in manufacturing ceramic filters. In this work, disc type ceramic filters(50$\phi$$\times$10t) were manufactured by vacuum forming processes using ceramic raw materials. The porosity and bulk density of disc type ceramic filers ranged from 86 to 89% and from 0.27 to 0.36 g/㎤, respectively. In this work disc type ceramic medium were tested utilizing coupon experimental apparatus. Disc type filters showed high collection efficiencies over 99.96% with Darchs law coefficients of 4.1$\times$10(sup)10~9.63$\times$10(sup)10/$m^2$ depending on mean pore sizes. In addition, filtration and detachment of ceramic filters turned out to be performed effectively using 10 cm/sec face velocity, 5 minutes filtration cycle, 100msec pulse jet valve opening time and 3 bar pulsing pressure.

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The evolution of a late-type galaxy in a Coma-like cluster

  • Hwang, Jeong-Sun;Park, Changbom;Banerjee, Arunima
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.64.1-64.1
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    • 2016
  • We study the evolution of a late-type galaxy (LTG) in a rich cluster environment by using N-body/SPH simulations. To do that we perform a set of simulations of a LTG falling in a Coma-like cluster and also the LTG colliding with early-type galaxies (ETGs) multiple times in the cluster environment. We use a catalog of the Coma cluster in order to estimate the typical number of collisions and the closest approach distances that a LTG would experience in the cluster. We investigate the cold gas depletion and star formation quenching of our LTG model influenced by the hot cluster gas as well as the hot halo gas of the colliding ETGs.

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Graphic Simulator of the Mechanical Master-Slave Manipulator (기계식 Master-Slave 조작기의 그래픽 시뮬레이터)

  • 이종열;송태길;김성현;홍동희;정재후;윤지섭
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.743-746
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    • 1997
  • The Master-Slave manipulator is the generally used remote handling equipment in the hot cell, in which the high level radioactive materials such as spent fuels are handled. To analyze the motion and to implement the training system by virtual reality technology, the simulator for M-S manipulator using the computer graphics is developed. The parts are modelled in 3-D graphics, assembled, and kinematics are assigned. The inverse kinematics of the manipulator is defined, and the slave of manipulator is coupled with master by the manipulator's specification. Also, the virtual workcell is implemented in the graphical environment which is the same as the real environment. This graphic simulator of manipulator can be effectively used in designing of the maintenance processes for the hot cell equipment and enhance the reliability of the spent fuel management.

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Effect of constraint severity in optimal design of groundwater remediation

  • Ko, Nak-Youl;Lee, Kang-Kun
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.217-221
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    • 2003
  • Variation of decision variables for optimal remediation using the pump-and-treat method is examined to estimate the effect of the degree of concentration constraint. Simulation-optimization method using genetic algorithm is applied to minimize the total pumping volume. In total volume minimization strategy, the remediation time increases rapidly prior to significant increase in pumping rates. When the concentration constraint is set severer, the more wells are required and the well on the down-gradient direction from the plume hot-spot gives more efficient remediation performance than that on the hot-spot position. These results show that the more profitable strategy for remediation can be achieved by increasing the required remediation time than raising the pumping rate until the time reaches a certain limitation level. So, the remediation time has to be considered as one of the essential decision variables fer optimal remediation design.

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Implementation of Real-Time Thermal Environment for Virtual Reality Using Gain Scheduling and Cascade Control (게인 스케쥴링과 캐스케이드 제어에 의한 가상현실용 열환경의 실시간 구현)

  • Sin, Yeong-Gi;Jang, Yeong-Su;Kim, Yeong-Il
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.7
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    • pp.567-573
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    • 2001
  • A real-time HVAC system is proposed which implements real-time control of thermal environment for virtual reality. It consists of a pair of hot and cold loops that serve as thermal reservoirs, and a mixing box to mix hot and cold air streams flowing if from loops. Their flow rates are controlled in real-time to meet a set temperature and flow rate. A cascade control algorithm along with gain scheduling is applied to the system and test results shows that the closed-loop response approached set values within 3 to 4 seconds.

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A Study on the Earthing System of Using Discharge Electrodes (방전전극을 사용한 접지시스템에 관한 연구)

  • Seol, Dong-Hwa;Kim, Myeong-Saeng;Kim, Chang-Bong;Woo, Jea-Wook
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.8 no.2
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    • pp.84-89
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    • 2009
  • This paper has purpose of designing the earthing system installed on the ground without laying under the ground. As a solution for green IT environment to solve the existing earthing system, the third generation earthing machine was designed by using discharge electrodes, catalyzer, and hot wires. As a result of comparison, it found that the third generation earthing system suggested in this research had more increased discharge currents by 31[A] and the speed 25 times faster than the second generation earthing system. The suggested earthing system is allowed to be installed on the ground and solve construction costs, time, area, and environment pollution, which are problems in the existing earthing system. In addition, as the earthing technique has recently developed, the earthing system is classified by generation based on capacity.

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