• Title/Summary/Keyword: co-cycle

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A Study on Mission Profile and Determination of Durability Test Parameters in the Hydraulic Clutch System (Hydraulic Clutch System의 Mission Profile 및 내구시험모수 결정에 관한 연구)

  • Lee, Sang-Cheon;Hur, Man-Dae;Lee, Chun-Gon;Kim, Jae-Young;Kang, Ji-Woo;Lee, Hong-Bum;So, Yoon-Sub;Lee, Jong-Hyung;Min, Byung-Gil;Lee, Jae-Yul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.5
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    • pp.521-528
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    • 2009
  • One of reliability measurements of vehicle is estimated by driving mileage but the reliability of component, such as an hydraulic clutch system, is defined from the number of successful operational cycle. Relationship between these reliability measurement variables(mileage and cycle) should be examined first of all in the reliability estimation of components. Relationship between mileage and cycles is commonly known as linear function. However, the gradient depends on the operational environmental condition. Therefore, estimation of mission profile variable should be done with correlation analysis at the same time. In this paper, we derive mission profile variable of an hydraulic clutch system by field vehicle test and suggest the determination process of durability test parameters of CMC(Clutch Master Cylinder) with mission profile variable.

A Study on the Amount of Carbon Emission of Organic Materials through Life-Cycle Assessment (LCA) (전과정평과를 통한 유기농자재의 탄소배출량 산정연구 -유기질비료를 중심으로-)

  • Yoon, Sung-Yee;Kwon, Hyuk-Jun
    • Korean Journal of Organic Agriculture
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    • v.19 no.1
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    • pp.23-38
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    • 2011
  • ● The current world is suffering abnormal climate caused by global warming. The main cause of global warming is greenhouse gas such as carbon dioxide. The carbon labeling system and carbon traceability system being pushed ahead in the agricultural sector is the policy for responding to climate change to reduce greenhouse gas emissions. To make this policy more effective and enhanced, the amount of carbon emissions should be calculated based on the kind of crops or the various businesses in the agricultural sector. Therefore, in order to estimate the accurate amount of carbon emissions, it is necessary to establish carbon dioxide emission intensity of various agricultural materials added onto the agriculture, and to calculate the amount of carbon dioxide emission for each crop according to agricultural production. The purpose of this study is to establish the amount of emission, emission per agricultural materials, of agricultural materials being added for crop production as a basic step, and emission intensity which can be used in the future market in order to estimate accurate amount of carbon emission in all the policies being promoted in the agricultural sector. Therefore, in this study, in order to build LCI D/B about organic fertilizers among many organic materials added onto the organic agriculture sector, one leading company in organic fertilizer production was selected and LCA was conducted for this leading company. We had to build the intensity and integrated average concept of intensity upon the two cases once production farmers for their own consumption and farms besides organic fertilizer company were categorized even if it's little amount. But in this study, individually produced organic fertilizers were excluded. Calculated results are following. Carbon emission of mixed expeller cake fertilizer in organic fertilizer was 1,106,966.89kg-$CO^2$ and emission intensity was 0.01606kg-$CO^2$, respectively. Total emission of mixed organic fertilizers was 241,523.2kg-$CO^2$ and emission intensity was 0.01705kg-$CO^2$. And total emission of organic compound fertilizers was 94,592.66kg-$CO^2$ and emission intensity was 0.01769kg-$CO^2$, respectively.

Application of Carbon Tracking System based on Ensemble Kalman Filter on the Diagnosis of Carbon Cycle in Asia (앙상블 칼만 필터 기반 탄소추적시스템의 아시아 지역 탄소 순환 진단에의 적용)

  • Kim, JinWoong;Kim, Hyun Mee;Cho, Chun-Ho
    • Atmosphere
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    • v.22 no.4
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    • pp.415-427
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    • 2012
  • $CO_2$ is the most important trace gas related to climate change. Therefore, understanding surface carbon sources and sinks is important when seeking to estimate the impact of $CO_2$ on the environment and climate. CarbonTracker, developed by NOAA, is an inverse modeling system that estimates surface carbon fluxes using an ensemble Kalman filter with atmospheric $CO_2$ measurements as a constraint. In this study, to investigate the capability of CarbonTracker as an analysis tool for estimating surface carbon fluxes in Asia, an experiment with a nesting domain centered in Asia is performed. In general, the results show that setting a nesting domain centered in Asia region enables detailed estimations of surface carbon fluxes in Asia. From a rank histogram, the prior ensemble spread verified at observational sites located in Asia is well represented with a relatively flat rank histogram. The posterior flux in the Eurasian Boreal and Eurasian Temperate regions is well analyzed with proper seasonal cycles and amplitudes. On the other hand, in tropical regions of Asia, the posterior flux does not differ greatly from the prior flux due to fewer $CO_2$ observations. The root mean square error of the model $CO_2$ calculated by the posterior flux is less than the model $CO_2$ calculated by the prior flux, implying that CarbonTracker based on the ensemble Kalman filter works appropriately for the Asia region.

Study on Selection of Water Treatment Filtration System to Cope with Climate Change (기후변화 대응을 위한 수처리 여과시스템 선정 방안 연구)

  • Hwang, Yun-Bin;Park, Ki-Hak
    • Journal of Climate Change Research
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    • v.9 no.1
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    • pp.75-80
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    • 2018
  • The problem of water shortages and water related disasters caused by climate change has increased the seriousness of water problems and the importance of water treatment technology capable of securing clean water is expanding. In this study, we analyzed not only the water pollutant generated by the filtration system technology of various water treatment technologies but also the indirect greenhouse gas emissions generation, and analyzed the influence on the environment. The subjects of study are Fabric Filter, Reverse Osmosis System and Pressurized Microfiltration Device which are widely used for water treatment and we analyzed the impact on the environment using the Life Cycle Assessment (LCA) method using the electricity amount necessary for use, the water purification efficiency, the throughput per ton and the cost. The amount of greenhouse gas generated when the Pressurized Microfiltration Device operates for 1 year is $2.15E+04kg\;CO_2-eq$., Fabric Filter is $3.29E+04kg\;CO_2-eq$., and Reverse Osmosis System is $1.68E+05kg\;CO_2-eq$. As a result of analyzing the amount of greenhouse gas generated at the time of purifying 1 ton of the Pressurized Microfiltration Device and the conventional filtration system, the Pressurized Microfiltration Device was $20.5g\;CO_2-eq$., Fabric Filter was $34.7g\;CO_2-eq$., and Reverse Osmosis System was $191.7g\;CO_2-eq$. The amount of greenhouse gas generated was calculated to be 41.0% less than that of the Fabric Filter by the Pressurized Microfiltration Device and 89.3% less than the Reverse Osmosis System. From the viewpoint of climate change, it is necessary to select a filtration system that takes climate change into account, not from the viewpoint of water quality removal efficiency and economic efficiency according to future water treatment applications, and it is necessary to select a water treatment filtration system more researches and improvements will be made for.

Increasing Effects of Apoptosis When Co-treated Scutellaria barbata D. Don. with Anti-cancer Drugs (반지련(半枝蓮)과 항암제 병용 투여에 의한 암세포 성장 저해에 관한 연구)

  • Nam, Ju-Young;Sung, Jung-Suk;Jun, Hyun-Ik;Lee, Jeong-Won;Kwon, Su-Kyung;Kim, Dong-Il
    • The Journal of Korean Obstetrics and Gynecology
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    • v.22 no.1
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    • pp.125-139
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    • 2009
  • Purpose: This experiment was designed to find out increasing effects of S. barbata. co-treatment with anti-cancer drugs at cancer cell's growth inhibition effect. Methods: Divergent observational study of the S. barbata. co-treatment with Cisplatin treatment on HeLa cell. Cell viability using MTT assay, Cell Culture and Cytotoxicity Studies, Cell Cycle Analysis, Annexin V-FITC/PI assay, Cell morphological assessment, PARP cleavage using Western blotting analysis when HeLa cell were co-treated with Cisplatin and Scutellaria Barbata extracts. Results: When HeLa cell were co-treated with Cisplatin and Scutellaria Barbata extracts, we found out viability of HeLa cell, changing in the distribution of cell cycle, Annexin V-FITC staining, DAPI staining, PARP clavage protein assay by Western-blot. So Scutellaria Barbata extracts have increased apoptosis Conclusion: When co-treated Scutellaria Barbata extracts with anti-cancer drugs, the anti-cancer effects were increased. We still not sure which constituent apoptosis at cancer cells and activates anti-cancer effects suppressing, but we believe that it'll be revealed here after with following experiments.

The Emission Characteristics of Bio-Diesel Fuel in Heavy-Duty Engine (바이오 디젤 적용에 따른 대형엔진의 배출가스 특성)

  • Kim, Sun-Moon;Eom, Myoung-Do;Hong, Ji-Hyung
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.5
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    • pp.499-506
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    • 2010
  • Recently, a great deal of attention have been directed to the use of alternative fuels as a means to reduce vehicular emissions. As one of the promising alternative fuels, bio-diesel has advantages of a wide adaptability without retrofit of diesel engine. It is also effective enough to reduce CO, THC, $SO_x$, polycyclic aromatic hydrocarbons (PAHs) and PM. In this study, we investigated the emission characteristics of biofuels between different operating conditions, i.e., engine speed (1,400 rpm and 2,300 rpm), engine load (10% and 100%), bio-diesel blending (BD0, BD5 and BD20), and recirculation (EGR) rate of exhaust gas (0% and 20%). Relative performance of the system was evaluated mainly for the greenhouse gases ($CH_4$, $N_2O$ and $CO_2$). In addition, emission characteristics of ND-13 mode were also tested against both greenhouse gases and other airborne pollutants under emission regulation. The relative composition of bio-diesel has shown fairly clear effects on the emission quantities of CO, THC, and PM emission, although it was not on $NO_x$ and greenhouse gases. EGR rate has shown trade-off characteristics between $NO_x$ and PM.

Minimization of Tilting Moment of Co-Rotating Scroll Compressor by Design of Back Pressure Chamber (배압실의 설계를 통한 상호회전 스크롤 압축기의 전복 모멘트 최소화)

  • Gu, In-Hoe;Park, Jin-Mu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.5 s.176
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    • pp.1305-1313
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    • 2000
  • In a co-rotating scroll compressor, both scrolls rotate on their fixed axes contrary to the conventional orbiting type scroll machine. This implies fixed locations and directions of the gas pressure force and sealing force. Because the tilting moment is mainly caused by interplay between the resultant force of above forces and bearing reaction force, the variation during one cycle is relatively small. Under real operation, this moment is balanced by the restoring moment created by the reaction between the baseplate and thrust bearing or between the scroll tip and baseplate. If these reactions become too large, greater torque is required due to increased friction in addition to the wear of mating parts. Consequently, appropriate study and minimization of tilting moment is important in the design of scroll machines. In this study, taking into account of the small variation of tilting moment during one cycle, we minimize the moment and thrust bearing reaction force by a properly designed back pressure chamber. As a result, for both the driving and driven scrolls, the tilting moment and the reaction force of thrust bearing can be minimized. And the stability is improved for all cases.

A Proposal of Life Cycle CO2 Assessment Techniques for Building in Construction Stage by BIM LOD (건설단계 BIM을 이용한 건축물의 전 과정 CO2 평가 기법 제안에 관한 연구)

  • Bang, Jun-Sik;Tae, Sung-Ho;Roh, Seung-Jun;Keum, Won-Seok
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.05a
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    • pp.53-54
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    • 2012
  • This study is aimed at utilizing LCA processor with BIM LOD, eliciting the problems of the existing environmental assessment by constructing the database for environmental values of green buildings. For these objects, environmental load database of BIM construction material and evaluation process are presented, after matching BIM family based environmental load database which is available during evaluation stage, input-output tables and Korea LCI database to standard item code of public procurement service. It is a important factor in environmental assessment of building to develop database unit of standard item code for BIM and construction material. Thus, the results of this study are expected to provide basic data for improving effectiveness of construction through BIM based environmental load evaluation database. Furthermore, the provided environmental load database unit for construction material is considered to be available as basic information for BIM study by suggesting a processor connecting BIM with LCA and along with this, continuous examination on the connection process is needed.

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Practical Experiences with Corrosion Protection of Water Intake Gates in Mekong River

  • Phong, Truong Hong;Tru, Nguyen Nhi;Han, Le Quang
    • Corrosion Science and Technology
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    • v.7 no.6
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    • pp.328-331
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    • 2008
  • Corrosion behaviour of water intake gate steel structures with different protective measures was investigated. Five material alternatives were taken for investigation, including: imported and recycled stainless steel, carbon steel with hot zinc spraying, painting and composite coatings. Results of corrosion rate for carbon steel, SUS 304, hot zinc spray coats in three water systems of Mekong river basin (saline, blackish and fresh) were also presented. Corrosion rate of carbon steel decreased with decreasing salinity in the investigated water environments. Meanwhile, these values for zinc coated steel, behaved by another way. Environmental data for these systems were filed and discussed in relation with corrosion characteristics. Method of Life Cycle Assessment (LCA) was applied in materials selection for water intake gate construction. From point of Life Cycle Cost (LCA) the following ranking was obtained: Zinc sprayed steel < Recycled stainless steel < Composite coated steel < Painting steel < SUS 304 From investigated results, hot zinc spray coating has been applied as protective measure for steel structures of water intake systems in Mekong river basin.

Research and practice of health monitoring for long-span bridges in the mainland of China

  • Li, Hui;Ou, Jinping;Zhang, Xigang;Pei, Minshan;Li, Na
    • Smart Structures and Systems
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    • v.15 no.3
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    • pp.555-576
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    • 2015
  • The large number of long-span bridges constructed in China motivates the applications of structural health monitoring (SHM) technology. Many bridges have been equipped with sophisticated SHM systems in the mainland of China and in Hong Kong of China. Recently, SHM technology has been extended to field test systems. In this view, SHM can serve as a tool to develop the methods of life-cycle performance design, evaluation, maintenance and management of bridges; to develop new structural analysis methods through validation and feedback from SHM results; and to understand the behavior of bridges under natural and man-made disasters, rapidly assess the damage and loss of structures over large regions after disasters, e.g., earthquake, typhoon, flood, etc. It is hoped that combining analytical methods, numerical simulation, small-scale tests and accelerated durability tests with SHM could become the main engine driving the development of bridge engineering. This paper demonstrates the above viewpoint.