• Title/Summary/Keyword: gas leak

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Low-income Households' Experiences and Perception of Home Energy Cost Burdens in Cheongju, South Korea (청주시 저소득 가구의 가정 에너지 비용 부담 경험과 인식)

  • Lee, Hyun-Jeong
    • Journal of the Korean housing association
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    • v.26 no.5
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    • pp.79-87
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    • 2015
  • This study explored low-income households' experiences and perception of home energy cost burdens and determinants of the perceived home energy cost burdens. Between March and July 2014, a questionnaire survey was administered in Cheongju, South Korea. Among the 434 useable responses collected, responses from 218 households with monthly income less than 2,500,000 Korean Won (KRW) were compared with those of 216 households with higher incomes. The main findings are as follows. In the past three years, more than 10 percent of low-income households had had their electricity cut off; 5.7 percent had had their city gas cut off. To pay for their home energy expenses, nearly 70 percent of the low-income households had had to limit their heating, cooling or spending for other necessities; 38.3 percent had to borrow money. Low-income households reported more problems paying for home energy than higher-income households did. Households with more negative evaluation of rainwater leak, no one staying at home all day, monthly income less than 1,500,000 KRW and householders in their 40s and 50s tended to perceive a heavier home energy cost burden. Finally, the most popular support programs were fuel assistance and discounts on energy bills.

Design and Evaluation of a Crankcase Relief Valve Spring for LNG-Fueled Ships (LNG 연료추진 선박용 크랭크실 릴리프 밸브 스프링의 설계 및 평가)

  • Lee, Hyo Ryeol;Ahn, Jung Hwan;Ahn, Byoung Hoon;Kim, Hwa Young
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.24 no.3
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    • pp.263-269
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    • 2015
  • Growing concerns regarding air pollution have recently increased the demand for liquefied natural gas (LNG) fueled ships. LNG-fueled ships are equipped with an explosion relief valve in the crankcase to relieve excessive pressure and stop flames from emitting from the crankcase. In this study, a finite element analysis was conducted to evaluate the crankcase relief valve disk spring design using an ANSYS Workbench, v.15. The setting pressure, leak and explosion test performed by european standard EN14797 to evaluate function and mechanical integrity of crankcase relief valve. The tests results indicate that the pressure of the crankcase relief valve is 3.05 bar, with no air leakage at 2.97 bar. Finally, the mechanical integrity of the crankcase relief valve was confirmed through an explosion test in which the valve plate assembly, flame arrester, and other parts were safe from fracturing.

A Study on the Simultaneous Reduction of NOx and Soot with Diesel-Methanol Stratified Injection System in a Diesel Engine (Part II : Combustion and Exhaust Characteristics of Stratified Injection) (층상연료분사(경유/메탄올)를 이용한 디젤엔진의 NOx와 Soot 동시 저감에 관한 연구 (제2보 : 층상분사 연소특성 및 배기 특성))

  • Kang, B.M.;Lee, T.W.;Chung, S.S.;Ha, J.Y.
    • Journal of ILASS-Korea
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    • v.7 no.1
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    • pp.7-13
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    • 2002
  • This paper is study on simultaneous reduction of NOx and soot for direct injection diesel engine using high and low cetane fuels. The stratified injection system was applied for diesel engine to use high and low cetane fuel. In this study, diesel fuel was used as high cetane fuels, methanol was used as low cetane fuels. Some parts of the injection system, ie. Nozzle holder. delivery vale, was remodeled to inject dual fuel sequentially from one injector. The leak injection quantity ratio of dual fuel was certificated by volumetric ratio at injection quantity experiment. According as concentration of low cetane fuel was varied, combustion experiment was performed using Toroidal and Complex chamber. Also, exhaust gas and fuel consumption were measured at the same time. Simultaneous reduction of NOx and soot was achieved at complex chamber regardless of concentration of low cetane fuel. However, according as concentration of low cetane fuel was increased, THC and CO was increased.

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A Study on Intelligent Space Design Supporting the Elderly - Focused on the Needs of the Aged on Digital Systems in Residential Space - (노인을 위한 지능형 공간환경 연구 - 주거공간의 디지털 시스템화를 위한 노인요구 조사를 중심으로 -)

  • Oh, Chan-Ohk
    • Korean Institute of Interior Design Journal
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    • v.17 no.5
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    • pp.61-71
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    • 2008
  • The study alms to seek a plan of applying the digital technology to housing for the elderly. The purpose of the study was to grasp the needs of the aged on 30 types of digital systems in housing. The subjects were 120 persons aged of more than 60 years and lived in Busan. Data were collected by the individual interview. The following results were drawn from this study. First, the needs of the aged on the digital systems categorized as safe and security, control of indoor environment, and housework support were very high and should be provided at first. Second, the necessary types of digital systems which should be provided to the digital home for the elderly were digital systems for heating control, health checking, sensing of fire and gas leak, and house cleaning. Also, the basic types of digital systems were ones for invasion and burglarproof, emergency, air cleaning, automatic facet, door locking, and waste collecting. Third, the Income and usage level of digital equipment of the aged influenced to the floods of the aged on the digital system. Therefore, in addition to the necessary and basic types of digital systems mentioned above, the income and usage level of digital equipment should be considered in planning the digital home for the elderly.

Study of Failure Examples of Automotive Electronic Control Suspension System Including Cases with Wiring Disconnection and Air Leakage (배선 단선과 에어 누설에 관련된 자동차 ECS 시스템의 고장사례 고찰)

  • Lee, Il Kwon;Park, Jong Geon;Shin, Myung Shin;Jang, Joo Sup
    • Tribology and Lubricants
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    • v.29 no.3
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    • pp.180-185
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    • 2013
  • The purpose of this study was to analyze the tribological characteristics of the Electronic control suspension System in a car. In the first example, the cilp used to attach the front electronic control suspension(ECS) system's control actuator was fastened very tightly. Thus, the wire was cut because of continual rotation of the shock-up shover piston rod used to adjust the height of the car. This verified the disconnection phenomenon where wire damaged makes it impossible for the ECS system to send signal to the actuator. The second example, involved a minute hole that allowed gas to leak from the ECS system. As a result, the height of the car verified the down phenomenon. In the third example, the resistance of a wire measured at $0.21{\Omega}$, when the G sensor was disconnected from the system. This verified the system shutdown and lighting of the ECS warning lamp because of body interference caused by a slight pressure on the battery cover. Therefore, quality control is always necessary to ensure safety and durability of a car.

Study on the Safety Standard Establishment of Halogen Clean Extinguishing Agents (할로겐화합물청정소화약제 안전기준 설정에 관한 연구)

  • Cho, Jung-Rae;Lee, Jong-Ho
    • Fire Science and Engineering
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    • v.32 no.5
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    • pp.22-33
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    • 2018
  • The amount of halogen clean fire extinguishing agents has been increased by the excellent features of extinguishing, adaptability and no residue. On the other hand in situations without a hazard assessment and safety standard of agents, chemical accidents by the agents occurs frequently. This study was performed to propose the halogen clean agents' regulatory exposure limit and safety standard including the quantitative ventilation system with gas leak monitoring, hazard recognition and optimal personal protection selection through a literature review and experimental research.

A Study on the RCM Development Using USN/ZigBee in Power Industry - ServiceScience Prototype - (전력산업에서 USN/ZigBee를 적용한 RCM 개발에 관한 연구 - 서비스사이언스 프로토타입 -)

  • Park, Jeong-Sun;Cho, Hong-Gi;Lee, Sang-Min;Lee, Dong-Nyuk
    • Journal of the Korea Safety Management & Science
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    • v.11 no.1
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    • pp.183-191
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    • 2009
  • The purposes of this research are presenting a new business model by introducing USN/ZigBee and measuring productivity using BSC(Balanced scorecard), and becoming a cornerstone by presenting a prototype of ServiceScience which is getting more attention from Industrial Engineering and Management. The new business model consists of development of leak current monitoring sensor using USN/ZigBee and the adoption of RCM(Reliability-Centered Maintenance) using knowledge-based system at current distribution. Additionally, for the measurement of this new model's productivity, ESC is used, and the strategic map and measurement indices are produced. The main contributions of this paper are showing a concrete model of ServiceScience and demonstrating this model can be extended to similar areas like are gas, water etc.

A study on importance of MSDS education (MSDS 교육의 중요성에 관한 연구)

  • Choi, Sung-Jai
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.6
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    • pp.209-215
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    • 2015
  • Following the semiconductor industry's growing, various types of toxic gases and caustic chemicals, HF(Hydrofluoric acid), HCI (Hydochloric acid), $H_2O_2$ (Hydrogen peroxide), $H_2SO_4$ (Sulfuric acid), and Piranha, were using on the semiconductor manufacturing process. Therefore many gas leakage accidents that produce huge losses of lives were caused by the processes. This research deeply considers two basic solutions that the necessity of MSDS education on university for reducing damage of lives and protecting life from chemical leak accidents such as a HF accident in Gumi, Korea and the use of GHS, REACH and the comprehension of propriety about using MSDS for keeping safety from conflagrations by released poison chemical materials.

PEFP 빔라인의 진공 펌프 설계를 위한 압력 프로파일 계산

  • Lee, Hwa-Ryeon;Kim, Han-Seong;Gwon, Hyeok-Jung;Jo, Yong-Seop
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.292-292
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    • 2010
  • 양성자기반공학기술개발단에서는 100MeV와 20MeV의 가속기를 개발하고 있으며 빔 이용을 위하여 각 에너지에 5개의 빔라인을 구축 할 계획이다. 빔라인에는 각 마그넷과 빔 계측, 진공 등의 부품이 포함되어 있다. 본 연구에서는 빔라인의 기초 구성품인 진공 부품의 설계를 위한 압력의 계산을 수행하였다. 각 빔라인 재질에 따른 gas load는 표면의 아웃게싱이 주요하게 고려되었으며 고진공용 Cu gasket의 진공 leak는 거의 없다고 가정하였다. 재질은 스테인레스스틸과 알루미늄의 두 가지 경우를 사용하였으며 주 배기 펌프는 이온펌프로 펌핑 스피드 125L/s의 diode 타입이다. 빔튜브의 사이즈는 CF6"의 규격 플랜지를 기본으로 빔 사이즈가 고려된 여러 플랜지의 조합으로 내부 부피를 구할 수 있었다. 빔라인 뿐만 아니라 타겟룸에 위치되어지는 튜브를 합한 경우와 펌프의 개수를 다르게 하였을 때에도 길이에 따른 압력의 프로파일을 계산하였다. 빔을 분배해 주는 AC 마그넷 이전에 이온펌프 한 개를 위치하였을 때 스테인레스스틸 빔 튜브의 경우에 최대값은 1.3E-6 torr, 최소값은 1.7E-6 torr 으로 계산 되었다. 이 결과는 가속기의 아래쪽 3개의 빔라인을 동시에 배기하고 빔 조사가 가능하도록 운영되는 조건이며 운영 마진 2배를 고려한다고 하여도 최소 진공도는 3.4E-6 torr 이다. 이온펌프는 일반적으로 9.0E-6 torr 이하에서 사용이 가능하므로 이온펌프 1개의 진공도로도 운영에 무리가 없으며 이온펌프의 수가 증가됨에 따라서 최대 도달 압력이 낮아짐을 알 수 있다.

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Process Development of Pyrolysis Liquefaction for Waste Plastics (폐플라스틱의 열분해 유화기술 개발)

  • Nho, Nam-Sun;Shin, Dae-Hyun;Park, Sou-Won;Lee, Kyong-Hwan;Kim, Kwang-Ho;Jeon, Sang-Goo;Cho, Bong-Gyu
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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    • pp.523-526
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    • 2006
  • The target of this work was the process development of demonstration plant to produce the high quailty alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70t/y and the pi lot plant of 360 t/v had been developed. Main research contents in this step were the process performance test of pilot plant ot 360ton/year and the development of demonstration plant of 3 000 t/y which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/v showed components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

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