• Title/Summary/Keyword: Real Gas

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The Research for effect of lubricant oil aging on environmental performance (자동차 윤활유의 성상 및 열화가 환경성에 미치는 영향 연구)

  • Kim, Jeong-Hwan;Kim, Ki-Ho;Ha, Jong-Han;Jin, Dong-Young;Myung, Cha-Lee;Jang, Jin-Young
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.1
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    • pp.12-24
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    • 2017
  • The main purpose of this research is for the investigation on the impact of engine oil aging on PM and DPF. It is widely known that lubricant specifications and consumption from an ICE have significantly influenced on the regulated and unregulated harmful emissions as the engine operating conditions. Considering DPF clogging phenomena with lubricant-derived soot/ash components, simulated aging mode for the DPF was newly designed for engine dynamometer testing. PM/ash accumulation cycle were developed in reflecting real-world engine operating conditions for the increment of engine oil consumption and natural DPF regeneration for the ash accumulation. The test duration for DPF aging reached around 100hrs with high- and low-SAPS engine oils, respectively. Using high SAPs engine oil made more PM/ash accumulation compared with low SAPs engine oils and it could accelerate fouling of EGR in engine. Fouling of EGR made effects on more harmful exhaust gases emissions. The test results on engine lubricant under engines operating conditions will deliver for the establishment of regulated and unregulated toxic emissions policy, lubricant quality standard.

A Framework for Digitalizing Handwritten Document using Digital Pen and Handwriting Recognition Technology (디지털펜과 필기체인식 기술을 이용한 수기문서 전자화 프레임워크)

  • Son, Bong-Ki;Kim, Hak-Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.3
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    • pp.1417-1426
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    • 2011
  • Business still relies heavily on pen and paper for legal reasons or convenience. The handwritten document is to be converted into digitalized document for IT system to manage and process in real time. Because the previous document digitalization systems convert the handwritten documents into digitalized documents by scanning and post-processing the documents, it is difficult to seamlessly proceed the work process. This paper proposes the LiveForm, a framework for digitalizing handwritten document using digital pen and handwriting recognition technology. To prove the applicability of the proposed LiveForm, we also implement a LiveForm based service in industrial gas distribution process and analyze effects of the system. The LiveForm generates the same digital image as the handwritten document by writing up the paper with absolute coordinates by digital pen and converts the handwriting data to digital text to insert the information into back-end system. The LiveForm based system eliminates scanning for document digitalization and data input with keyboard into back-end system in paper-based information gathering. Therefore, it is possible for the LiveForm to improve work process in various business areas.

Partial Discharge Detection of High Voltage Switchgear Using a Ultra High Frequency Sensor

  • Shin, Jong-Yeol;Lee, Young-Sang;Hong, Jin-Woong
    • Transactions on Electrical and Electronic Materials
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    • v.14 no.4
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    • pp.211-215
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    • 2013
  • Partial discharge diagnosis techniques using ultra high frequencies do not affect load movement, because there is no interruption of power. Consequently, these techniques are popular among the prevention diagnosis methods. For the first time, this measurement technique has been applied to the GIS, and has been tested by applying an extra high voltage switchboard. This particular technique makes it easy to measure in the live state, and is not affected by the noise generated by analyzing the causes of faults ? thereby making risk analysis possible. It is reported that the analysis data and the evaluation of the risk level are improved, especially for poor location, and that the measurement of Ultra high frequency (UHF) partial discharge of the real live wire in industrial switchgear is spectacular. Partial discharge diagnosis techniques by using the Ultra High Frequency sensor have been recently highlighted, and it is verified by applying them to the GIS. This has become one of the new and various power equipment techniques. Diagnosis using a UHF sensor is easy to measure, and waveform analysis is already standardized, due to numerous past case experiments. This technique is currently active in research and development, and commercialization is becoming a reality. Another aspect of this technique is that it can determine the occurrences and types of partial discharge, by the application diagnosis for live wire of ultra high voltage switchgear. Measured data by using the UHF partial discharge techniques for ultra high voltage switchgear was obtained from 200 places in Gumi, Yeosu, Taiwan and China's semiconductor plants, and also the partial discharge signals at 15 other places were found. It was confirmed that the partial discharge signal was destroyed by improving the work of junction bolt tightening check, and the cable head reinforcement insulation at 8 places with a possibility for preventing the interruption of service. Also, it was confirmed that the UHF partial discharge measurement techniques are also a prevention diagnosis method in actual industrial sites. The measured field data and the usage of the research for risk assessment techniques of the live wire status of power equipment make a valuable database for future improvements.

Experimental Study of Characteristics of Three-Ring Impedance Meter and Dependence of Characteristics on Electric Conductivity of Fluids (3-ring 임피던스미터의 유체 전기 전도도 독립성에 대한 실험적 연구)

  • Kim, Jong-Rok;Ahn, Yeh-Chan;Kim, Moo-Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.11
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    • pp.1027-1033
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    • 2010
  • A two-phase (gas-liquid) flow is a common phenomenon in fluidic systems, e.g., fluidic systems in the electro-magnetic or nuclear power generation industry and in the steel industry. The measurement of a two-phase flow is important for guaranteeing the safety of the system and for achieving the desired performance. The measurement of the void fraction, which is one of the parameters of the two-phase flow that determines the pressure drop and heat transfer coefficient, is very important. The time resolution achieved by employing the impedance method that can be used to calculate the void fraction from the impedance of the fluid is high because the electric characteristics are taken into account. Therefore, this method can be employed to accurately measure the void fraction without distortion of flow in real time by placing electrodes on the walls of the tubes. Coney analytically studied a ring-type impedance meter, which can be employed in a circular tube. The aim of this study is to experimentally verify the robustness of a three-ring impedance meter to variations in the electric conductivity of the fluid; this robustness was suggested by Coney but was not experimentally verified.

Membrane Characteristics for Removing Particulates in PFC Wastes (PFC제염폐액 내의 미립자 제거를 위한 여과막의 특성 연구)

  • Kim Gye-Nam;Lee Sung-Yeol;Won Hui-Jun;Jung Chong-Hun;Oh Won-Zin;Park Jin-Ho
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.3 no.2
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    • pp.149-157
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    • 2005
  • PFC(Perfluorocarbon) decontamination process is one of best methods to remove hot particulate adhered at inside surface of hot cell and surface of equipment in hot cell. It was necessary to develop a particulate filtration equipment to reuse PFC solution used on PFC decontamination due to its high cost and to minimize the volume of second wastewater. Contamination characteristics of hot particulate were investigated and then a filtration process was presented to remove hot particulate in PFC solution generated through PFC decontamination process. The removal efficiency of PVDF(Poly vinylidene fluoride), PP(Polypropylene), Ceramic(Al$_{2}$O$_{3}$ filter showed more than 95$\%$. The removal efficiency of PVDF filter was a little lower than those of other kiters at same pressure(3psi). A ceramic filter showed a higher removal efficiency with other filters, while a little lower flux rate than other filters. Due to inorganic composition, a ceramic filter was highly stable against radio nuclides in comparison with PVDF and PP membrane, which generate H$_{2}$ gas in e-radioactivity atmosphere. Therefore, the adoption of ceramic filter is estimated to be suitable for the real nitration process.

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How to Reflect Sustainable Development in Overseas Investment including Equator Principles (해외투자(海外投資)와 지속가능발전 원칙 - 적도원칙(赤道原則)(Equator Principles)을 중심으로 -)

  • Park, Whon-Il
    • 한국무역상무학회:학술대회논문집
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    • 2006.06a
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    • pp.45-72
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    • 2006
  • The Equator Principles are a set of voluntary environmental and social guidelines for ethical project finance. These principles commit banks and other signatories to not finance projects that fail to meet these guidelines. The principles were conceived in 2002 on an initiative of the International Finance Corporation and launched in 2003. Since then, dozens of major banks have adopted the Principles, and with these banks among them accounting for more than three quarters of all project loan market volume the Principles have become the de facto standard for all banks and investors on how to deal with potential social and environmental effects of projects to be financed. While regarding the Principles an important initiative, NGOs have criticised the Principles for not producing real changes in financing activities and for allowing projects to go through that should have been screened out by the Principles, such as the Sakhalin-II oil and gas project in Russia. In early 2006, a process of revision of the principles was begun. The Equator Principles state that endorsing banks will only provide loans directly to projects under the following circumstances: - The risk of the project is categorized in accordance with internal guidelines based upon the environmental and social screening criteria of the International Finance Corporation (IFC). - For all medium or high risk projects (Category A and B projects), sponsors complete an Environmental Assessment, the preparation of which must meet certain requirements and satisfactorily address key environmental and social issues. - The Environmental Assessment report addresses baseline environmental and social conditions, requirements under host country laws and regulations, applicable international treaties and agreements, sustainable development and use of renewable natural resources, protection of human health, cultural properties, and biodiversity, including endangered species and sensitive ecosystems, use of dangerous substances, major hazards, occupational health and safety, fire prevention and life safety, socio-economic impacts, land acquisition and land use, involuntary resettlement, impacts on indigenous peoples and communities, cumulative impacts of existing projects, the proposed project, and anticipated future projects, participation of affected parties in the design, review and implementation of the project, consideration of feasible environmentally and socially preferable alternatives, efficient production, delivery and use of energy, pollution prevention and waste minimization, pollution controls (liquid effluents and air emissions) and solid and chemical waste management. - Based on the Environmental Assessment, Equator banks then make agreements with their clients on how they mitigate, monitor and manage those risks through an 'Environmental Management Plan'. Compliance with the plan is required in the covenant. If the borrower doesn't comply with the agreed terms, the bank will take corrective action, which if unsuccessful, could ultimately result in the bank canceling the loan and demanding immediate repayment. - For risky projects, the borrower consults with stakeholders (NGO's and project affected groups) and provides them with information on the risks of the project. - If necessary, an expert is consulted. The Principles only apply to projects over 50 million US dollars, which, according to the Equator Principles website, represent 97% of the total market. In early 2006, the financial institutions behind the Principles launched stakeholder consultations and negotiations aimed at revising the principles. The draft revised principles were met with criticism from NGO stakeholders, who in a joint position paper argued that the draft fails by ignoring the most serious critiques of the principles: a lack of consistent and rigorous implementation.

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The study for VOCs analysis in long path by open path FT-IR spectrometer (Open path FT-IR spectrometer를 사용한 원거리의 VOCs 측정에 관한 연구)

  • Cho, Nam Wook;Cho, Won Bo;Kim, Hyo Jin
    • Analytical Science and Technology
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    • v.27 no.2
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    • pp.108-113
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    • 2014
  • The harmful materials as volatile organic compounds (VOCS) that is easy for gas to be changed from liquid on ambient temperature, those should be controlled by Korea Chemicals Management Association. The VOCs samples should be collected directly in place so that those could be analyzed. Generally but it couldn't avoid to have the risk of analyst. Moreover, if there is the place limited to entrance, it is impossible to collect directly and measure. Owing to such problem, it tried to be solved by open path FT-IR spectrometer that could be studied on the combustion gases within long path and VOCs samples were tried to measure to large volume by remote and real time. Firstly, it was to investigate optimized measured length between the system and benzene sample of VOCs. As result, The optimized measured length was confirmed with 15 meter length and the qualitative analysis could be measured on seven VOC samples. The calibration curve as quantitative analysis of benzene samples could be worked. On the basis of the result, the system as remote monitor could show to have potentiality.

Aethalometer-based Estimate of Mass Absorption Cross Section of Black Carbon Particles at an Urban Site of Gwangju (광주 지역에서 aethalometer 측정 블랙 카본 입자의 질량흡수단면 평가)

  • Park, Seung-Shik;Yu, Geun-Hye;Lee, Sang-Il;Bae, Min-Suk
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.5
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    • pp.727-734
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    • 2018
  • In this study, real-time absorption coefficients of carbonaceous species in $PM_{2.5}$ was observed using a dual-spot 7-wavelength Aethalometer between November 1, 2016 and December 31, 2017 at an urban site of Gwangju. In addition, 24-hr integrated $PM_{2.5}$ samples were simultaneously collected at the same site and analyzed for organic carbon and elemental carbon (OC and EC) using the thermal-optical transmittance protocol. A main objective of this study was to estimate mass absorption cross section (MAC) values of black carbon (BC) particles at the study site using the linear regression between aethalometer-based absorption coefficient and filter-based EC concentration. BC particles observed at 880 nm is mainly emitted from combustion of fossil fuels, and their concentration is typically reported as equivalent BC concentration (eBC). eBC concentration calculated using MAC value of $7.77m^2/g$ at wavelength of 880 nm, which was proposed by a manufacturer, ranged from 0.3 to $7.4{\mu}g/m^3$ with an average value of $1.9{\pm}1.2{\mu}g/m^3$, accounting for 7.3% (1.5~20.9%) of $PM_{2.5}$. The relationship between aerosol absorption coefficients at 880 nm and EC concentrations provided BC MAC value of $15.2m^2/g$, ranging from 11.4 to $16.2m^2/g$. The eBC concentrations calculated using the estimated MAC of $15.2m^2/g$ were significantly lower than those reported originally from aethalometer, and ranged from 0.2 to $3.8{\mu}g/m^3$, with an average of $1.0{\pm}0.6{\mu}g/m^3$, accounting for 3.7% of $PM_{2.5}$ (0.8~10.7%). Result from this study suggests that if the MAC value recommended by the manufacturer is applied to calculate the equivalent BC concentration and radiative forcing due to BC absorption, they would result in significant errors, implying investigation of an unique MAC value of BC particles at a study site.

An Energy-efficient LED Lighting Control Scheme with Provision of User Illumination Requirement (사용자 요구조도 보장 에너지 효율적 LED 조명 제어 기법)

  • Kim, Yong-Ho;Lee, Kwon-Hyung;Chang, Kap-Seok;Choi, Yong-Hoon;Kim, Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.11B
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    • pp.1383-1388
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    • 2011
  • Due to many recent activities on enforcement of the intensified environmental regulation such as the policies of curbing the greenhouse gas and the Restriction of Hazardous Substances (RoHS), the usage of Light emitting diode (LED) has been rapidly increased and energy efficient management of LED light system is regarded as an important technology to enhance the energy efficiency. In this paper, we propose an energy-efficient control scheme of LED light, being composed of multiple light sources. The proposed scheme controls the intensity of LED light source to minimize the total intensity while providing the quality of lighting service. The intensity of light is assumed to be proportional to power consumption, thus the objective is to minimize the total power consumption. A linear programming problem is formulated to find the optimal intensity of each light source and procedure to apply the proposed scheme in the real system is suggested. The performance evaluation results elucidate that the proposed scheme achieves over 20% improvement in power consumption of light intensity in comparison with the conventional dimming control scheme.

A Study on The Performance Verification and Economic Evaluation of ESS for Frequency Regulation Application (주파수조정용 ESS의 성능검증 및 경제성평가 알고리즘에 관한 연구)

  • Lee, Ju-Gang;Choi, Sung-Sik;Kang, Min-Kwan;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.5
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    • pp.738-744
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    • 2017
  • Recently, the installation of energy storage systems (ESSs) has increased in parallel with the extension of renewable energy resources. However, there has been no concrete analysis ofthe performance verification and economic evaluation of ESSs,which makes it difficult to perform aneffective installation and operation of an ESS. In particular, there are no international technical standards and guidelines on electric ESS for frequency regulation applications. Therefore, acomprehensive study on the power quality, impact on grid, extent of contribution, and cost benefit study of ESS are strongly being required. Under these backgrounds, this paper proposes a performance verification algorithm on ESS for frequency regulation application based on ananalysis of the AGC(Automatic Generation Control) performance verification method of PJM in USA. In addition,this paper proposes an economic evaluation algorithm on a 500 MW installation of ESS for frequency regulation applications using the account settlement of an expensive gas-fired generation plant and coal-fired power generation plant. From the simulation with real ESS operation data and 500 MW installation case, it wasconfirmed that the ESS showssuperior performance toany other conventional generators and provides anannual benefit of 500 MW ESS are between 345~429 billon won.