• Title/Summary/Keyword: Supply and Exhaust

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A Study of Expressway Tollbooth Metering Effect (고속도로 영업소 미터링 효과에 관한 연구)

  • Im, Jin-Won;Yoon, Jae-Yong;Lee, Eui-Eun;Kim, Kwan-Min
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.4
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    • pp.1-10
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    • 2011
  • According to the worldwide efforts to reduce greenhouse gases consequent upon climatic change, the field of road traffic is also making diverse efforts to reduce the emissions of greenhouse gases. Among these, the exhaust gases from vehicles, the so-called main culprit of the greenhouse gases will take place the more as delay and tie-up of vehicles ever take place. Accordingly, as a scheme for reducing the delay & tie-up of vehicles, it's possible to bring up the idea of supply of new facilities and management of the existing facilities; recently, a lot more focus is being put on the management of the existing facilities due to enormous amounts of construction cost. In the midst of growing concern for traffic demand management policy, it's about the time we should do research on the tollbooth metering on the expressway whose research is almost non-existent home and abroad. As a traffic demand management policy coming to happen in case of the management of pay expressway like Japan and Korea, this research analyzed the contents of tollbooth metering, its effect and its subsequent convenience. Especially as a tool for effect analysis, this research made an analysis using VISSIM-a micro-simulation tool. As the tollbooth metering promoted, as a part of green traffic promotion strategy, is expected to contribute to improvement in traffic flow and reduction in carbon emissions, etc. It seems that there needs to be continuous research work on the management plan & revitalization plan for maximization of its effect later as well.

A Study on the Phrsical and Mechanical Properties of Concrete with Ferro Copper Slag (동슬래그를 잔골재로 사용한 콘크리트의 물리.역학적 특성에 관한 연구)

  • Lee, Mun-Hwan;Lee, Sea-Hyun;Song, Tae-Hyeob
    • Journal of the Korea Concrete Institute
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    • v.15 no.3
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    • pp.361-368
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    • 2003
  • As the supply of aggregate needed in the construction site becomes difficult due to preservation of environment and exhaust of aggregate resource, a research for replacement aggregate in shortage is being actively progressed and a copper slag is also a kind of replacing aggregate. To use copper slag as fine aggregate of concrete, many studies are already conducted in each of the advanced countries and in the state of applying these at the site. In the year of 2000 a Korea industrial standard of Copper slag aggregate for concrete was established in our country so that this can be applied in the construction site. This study is to find out whether copper slag is equipped with the physical and chemical requirements for the use in concrete aggregate, and to analyze the dynamic properties of copper slag concrete that replaces 25, 50, 75, 100% of fine aggregate. Copper slag study not only satisfies the using condition of fine aggregate, but also reveals high level of physical property compared to ordinary concrete up to 50% of sand replacement rate. In the future after confirming the durability of concrete using copper slag, it is judged to be advantageous for the preservation of environment to use this as a replacement material for natural aggregate.

A Study on the Smoke Removal Equipment in Plant Facilities Using Simulation (시뮬레이션을 이용한 플랜트 시설물 제연설비에 관한 연구)

  • Doo Chan Choi;Min Hyeok Yang;MIn Hyeok Ko;Su Min Oh
    • Journal of the Society of Disaster Information
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    • v.20 no.1
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    • pp.40-46
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    • 2024
  • Purpose: In this study, in order to ensure the evacuation safety of plant facilities, we analyze the relationship between the height of smoke removal boundary walls, the presence or absence of smoke removal equipment, and evacuation safety. Method: Using fire and evacuation simulations, evacuation safety was analyzed through changes in the height of the smoke removal boundary wall, air supply volume and exhaust volume according to vertical dista. Result: In the case of visible drawings, if only 0.6m of boundary wall is used, the time below 5m reaches the shortest, and 1.2m of boundary width is 20% longer than when using smoke removal facilities. In the case of temperature, 1.2m is 20% longer than 0.6m when only the boundary width is used without smoke removal facilities. Conclusion: It was found that increasing the length of the smoke removal boundary wall could affect visibility, and installing a smoke removal facility would affect temperature. Therefore, it is determined that an appropriate smoke removal plan and smoke removal equipment should be installed in consideration of the process characteristics.

Method to Derive the Optimal Vent Position when Flammable Liquid Leaks Based on CFD (CFD 기반 인화성 액체 누출 시 최적의 환기구 배치 도출 방안)

  • Eun-Hee Kim;Seung-Hyo An;Jun-Seo Lee;Byung-Chol Ma
    • Journal of the Korean Institute of Gas
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    • v.28 no.1
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    • pp.11-18
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    • 2024
  • If flammable liquid leaks, vapor evaporated from the pool can cause poisoning or suffocation to workers, leading to secondary accidents such as fires and explosions. To prevent such damage, ventilation facilities shall be installed when designing indoor workplaces. At this time, the behavior varies depending on the characteristics of the leaked chemical, so it is necessary to select a suitable vent location according to the material. Therefore, 3D CFD simulations were introduced to derive optimal vent position and ventilation efficiency was quantitatively evaluated by vent position. At this time, assuming a situation in which flammable liquids leak at indoor workplaces to form pools, the concentration of vapor evaporated from pools was compared to derive the optimal vent position. As a result of research on toluene with high vapor density, ventilation efficiency was confirmed to be the highest at the upper supply-lower exhaust, and it is judged that introducing it can achieve about 3.7 times ventilation effect at the same maintenance cost. Through this study, it is expected that the workplace will be able to secure workers' safety by applying simulation results and installing ventilation ports.

Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2016 (설비공학 분야의 최근 연구 동향 : 2016년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.6
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    • pp.327-340
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    • 2017
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

A study on the theory of "Pyong-Yeol-Byong (評熱病論)" in 33th chapter of "SoMon (素問)" Yellow Emperor's Nei-Ching (黃帝內經) (황제내경(黃帝內經) 소문(素問) 평열병론(評熱病論)에 대(對)한 연구(硏究))

  • Moon, Hee-Seork;Hong, Won-Sik
    • Journal of Korean Medical classics
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    • v.3
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    • pp.399-443
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    • 1989
  • In this thesis, I intend to study the translational and clinical interpretation through the syndrom of "Pyong-Yeol-Byong", and reached the following conclusions. 1. Eum-Yang-Kyo (陰陽交)' 1) Meaning: "Eum" means "Essential and vital energy" "Yang" means "Evil factor affecting health" and "Kyo" means "cross-struggle." 2) Location of disease: Heat evil enter Hyeol-Bun (血分) 3) Pathogenesis: Heat evil invade Eum-Bun (陰分) and struggles with Health energy, therefore Eum-Chung (陰精) is exhausted and Heat-evil doesn't disapper, it damage Eum and exhaust fluid. Reach fever, rapid pulse raving and unable to take meal, not controled by sweating and sceach death. 4) Particularity of Syndrome: Heat enter Hyol-Bun, and Evil factor is enough and Health energy is insufficient, so that reveal the symptoms of high fever, delirium with coma, unable to take meals. 5) Therapy: It clears Gi-Bun heat evil (氣分熱邪) by Gypsum, Rhizoma Anemarrhenae, Flos Lonicerae, Fructus Forsythiae, Fructus Gardeniae, Radix Scutellanae Rhizoma Coptidis, and cools Blood by Cornu Rhinoceri Asiatici, Radix Rehmanniae, Cortex Moutan Radicis, Dae-Chung-Yob (大靑葉) Radix Arnebiae Seu Lithospermi. 2. Poong Gweol (風厥) 1) Meaning: Poong means wind-evil, Gweol means reversing up. 2) Location of disease: Disease complexes with TaeYang (太陽) in outer part, and with So-Eum (少陰) in inner part. 3) Pathogenesis: Tae-Yang-Gyeong (太陽經) accept wind-evil and So-Eum-Gyeong (少陽經) Kidney Energy reverse up so that fidgetiness not resolves by sweating. 4) Particularity of Syndrome: There are outer symptoms of fever, hydrosis with inner symptoms of fidgetinessis. 5) Therapy: Reduce Jok-Tae-Yang (足太陽) and Supply Jok-So-Eum (足少陰) by accupuncture, so cure Poong Gweol and make balance between Yeong (營) and Wi (衛). 3. Scrofula coused by wind-evil (勞風) 1) Meaning: It means accepting wind evil rest less. 2) Location of Disease: It locates lung 3) Pathogenesis: Because of accepting wind-evil restless, he take scrofula with damaging lung. 4) Particularity of disease: It is lung disease of aversion to wind and shiver, nape-stiffiness, dim eyesight, cough, disphea, vomitting sputum, if one camnot vomit sputum, he died by damage of lung. 5) Therapy: The period of therapy is different by age or strength of health energy, so I think must prevent Eum deficiency and clear fever no reduced in lung. 4. Shin-Poong (腎風) 1) Meaning: It means taking edema by accepting wind-evil, because the kidney controls water. 2) Location of Disease: It is that wind-evil envade kidney. 3) Pathogenesis : Water evil of kidney with wind-heat rises up to face, reach edema, puffines s of the lower eyelid, floating pulse, bombus, yellowish urine, hydrosis and hand-heating, drymouth and excessive thirsty, walkless by heaviness, menstrual disfunction, restless and unable to take meals, unable to lie flat, heavy cough if lie flat, and accepting wind-evil by deficiency of kidney function, so the function of dredging the water passage is not smooth, symptom of water and symptom of wind reveal together. 4) Therapy: Remove wind-heat, promote diuresis to eliminate tile wetness-evil, supplement the dificiency of kidney's Eum. Finally, we can know that later Fever Disease Medicime (溫病學) is affected to the theory of "Pyong Yeol Byong" in 33th Chapter of SoMoon (素問).

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Distribution of Agalmatolite Mines in South Korea and Their Utilization (한국의 납석 광산 분포 현황 및 활용 방안)

  • Seong-Seung Kang;Taeyoo Na;Jeongdu Noh
    • The Journal of Engineering Geology
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    • v.33 no.4
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    • pp.543-553
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    • 2023
  • The current status of domestic a agalmatolite mines in South Korea was investigated with a view to establishing a stable supply of agalmatolite and managing its demand. Most mined agalmatolite deposits were formed through hydrothermal alteration of Mesozoic volcanic rocks. The physical characteristics of pyrophyllite, the main constituent mineral of agalmatolite, are as follows: specific gravity 2.65~2.90, hardness 1~2, density 1.60~1.80 g/cm3, refractoriness ≥29, and color white, gray, grayish white, grayish green, yellow, or yellowish green. Among the chemical components of domestic agalmatolite, SiO2 and Al2O3 contents are respectively 58.2~67.2 and 23.1~28.8 wt.% for pyrophyllite, 49.2~72.6 and 16.5~31.0 wt.% for pyrophyllite + dickite, 45.1 and 23.3 wt.% for pyrophyllite + illite, 43.1~82.3 and 11.4~35.8 wt.% for illite, and 37.6~69.0 and 19.6~35.3 wt.% for dickite. Domestic agalmatolite mines are concentrated mainly in the southwest and southeast of the Korean Peninsula, with some occurring in the northeast. Twenty-one mines currently produce agalmatolite in South Korea, with reserves in the order of Jeonnam (45.6%) > Chungbuk (30.8%) > Gyeongnam (13.0%) > Gangwon (4.8%), and Gyeongbuk (4.8%). The top 10 agalmatolite-producing mines are in the order of the Central Resources Mine (37.9%) > Wando Mine (25.6%) > Naju Ceramic Mine (13.4%) > Cheongseok-Sajiwon Mine (5.4%) > Gyeongju Mine (5.0%) > Baekam Mine (5.0%) > Minkyung-Nohwado Mine (3.3%) > Bugok Mine (2.3%) > Jinhae Pylphin Mine (2.2%) > Bohae Mine. Agalmatolite has low thermal conductivity, thermal expansion, thermal deformation, and expansion coefficients, low bulk density, high heat and corrosion resistance, and high sterilization and insecticidal efficiency. Accordingly, it is used in fields such as refractory, ceramic, cement additive, sterilization, and insecticide manufacturing and in filling materials. Its scope of use is expanding to high-tech industries, such as water treatment ceramic membranes, diesel exhaust gas-reduction ceramic filters, glass fibers, and LCD panels.