• Title/Summary/Keyword: Cycle Efficiency

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An Organizational Maturity Assessment Model for Public Data Quality Management (공공데이터 품질관리를 위한 조직 성숙도 평가 모델)

  • Kim, Sunho;Lee, Changsoo;Chung, Seungho;Kim, Hakcheol;Lee, Changsoo
    • Informatization Policy
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    • v.22 no.1
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    • pp.28-46
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    • 2015
  • Although the demand for the use of public data increases in accordance with the expansion of Government 3.0, the poor level of data quality and its management currently implemented is becoming obstacles to opening data to the public. To improve the efficiency of management, linkage and usage for data, standardized processes for data quality management have to be prepared and appropriate data quality assessment criteria should be established. In this paper, we propose the organizational maturity model that can assess the public data quality management level. This model consists of the process reference model and the measurement framework. Fifteen processes grouped by the PDCA cycle are defined in the process reference model. The measurement framework measures the organizational maturity level based on process capability levels. The organizational maturity model can be used to establish objectives and directions for public data quality improvement by diagnosis of current level of public data quality management and problem solving. This model can also facilitate open to the private sector and activate usage of stable public data through reliability enhancement.

High Energy Density Germanium Anodes for Next Generation Lithium Ion Batteries (다음세대 리튬이온 배터리용 고에너지 밀도 게르마늄 음극)

  • Ocon, Joey D.;Lee, Jae Kwang;Lee, Jaeyoung
    • Applied Chemistry for Engineering
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    • v.25 no.1
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    • pp.1-13
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    • 2014
  • Lithium ion batteries (LIBs) are the state-of-the-art technology among electrochemical energy storage and conversion cells, and are still considered the most attractive class of battery in the future due to their high specific energy density, high efficiency, and long cycle life. Rapid development of power-hungry commercial electronics and large-scale energy storage applications (e.g. off-peak electrical energy storage), however, requires novel anode materials that have higher energy densities to replace conventional graphite electrodes. Germanium (Ge) and silicon (Si) are thought to be ideal prospect candidates for next generation LIB anodes due to their extremely high theoretical energy capacities. For instance, Ge offers relatively lower volume change during cycling, better Li insertion/extraction kinetics, and higher electronic conductivity than Si. In this focused review, we briefly describe the basic concepts of LIBs and then look at the characteristics of ideal anode materials that can provide greatly improved electrochemical performance, including high capacity, better cycling behavior, and rate capability. We then discuss how, in the future, Ge anode materials (Ge and Ge oxides, Ge-carbon composites, and other Ge-based composites) could increase the capacity of today's Li batteries. In recent years, considerable efforts have been made to fulfill the requirements of excellent anode materials, especially using these materials at the nanoscale. This article shall serve as a handy reference, as well as starting point, for future research related to high capacity LIB anodes, especially based on semiconductor Ge and Si.

Failure Mode and Effect Analysis for Remanufacturing of the Old Extrusion Press (노후 압출기의 재제조를 위한 고장모드 영향분석)

  • Jung, Hang-Chul;Yun, Sang-Min;Oh, Sang-Ho;Baeg, Chang Hyun;Kong, Man-Sik
    • Clean Technology
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    • v.27 no.4
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    • pp.297-305
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    • 2021
  • In the domestic aluminum industry, the extrusion process is a major process accounting for more than 40% of the total production. However, most domestic aluminum extrusion companies produce aluminum using old equipment that is more than 30 years old. Extrusion press is when the equipment is not replaced before the wear and breakage of major parts occur, reducing productivity and increasing the defect rate compared to new equipment. The old extrusion press often loses part drawings, so it is difficult to repair them properly on-site and to remanufacture them due to the lack of technical skills for maintenance. Therefore, a systematic remanufacturing plan must be designed from dismantling the equipment. In this study, remanufacturing FMEA was devised to remanufacture old extrusion press. The risk priority was analyzed by considering the degree of damage to the recycled parts, the cycle due to breakage/damage during the extrusion process, and the value of recycling resources due to remanufacturing. To standardize the remanufacturing process, remanufactured FMEA was performed through part analysis according to the structural analysis of the extrusion press. In addition, remanufacturing priorities were selected for each part, while remanufacturing itself was studied for efficiency of resource circulation and product quality stabilization.

Trends in the change of household labor in the middle-aged (중년세대의 가사노동 변화 트렌드)

  • Lee, Hyun Ah
    • Journal of Family Resource Management and Policy Review
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    • v.25 no.1
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    • pp.47-61
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    • 2021
  • The purpose of this study is to analyze the trend of changes in household labor among middle-aged generations who are facing dynamic changes in the middle of their life cycle. The research method is a literature study that examines and analyzes related data. Specifically, it aims to analyze the basic characteristics of middle-aged generations and trends in household labor, which are revealed through Time Use Survey, market trend reports, newspaper articles, and books. From the perspective of family resource management, housework is an unpaid activity performed by and for family members, and is an activity that can be replaced by purchasing goods or services from the market. This study focuses on the rapid growth of the home appliance market that replaces housework with the development of technology after industrialization, and how the change of technology affected the efficiency of housework. In addition, the composition and characteristics of middle-aged generations greatly changed according to changes in family structure, form, and family value. Examining the current state of housework and changing trends of middle-aged generations, which have different characteristics from previous generations, is significant in that it can predict future market trends and suggest implications for family policies that support the improvement of the quality of life of middle-aged generations.

Effect of AlF3 on Zr Electrorefining Process in Chloride-Fluoride Mixed Salts for the Treatment of Cladding Hull Wastes (폐 피복관 처리를 위한 염소계-불소계 혼합용융염 내 지르코늄 전해정련공정에서 삼불화알루미늄의 효과 연구)

  • Lee, Chang Hwa;Kang, Deok Yoon;Lee, Sung-Jai;Lee, Jong-Hyeon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.2
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    • pp.127-137
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    • 2019
  • Zr electrorefining is demonstrated herein using Zirlo tubes in a chloride-fluoride mixed molten salt in the presence of $AlF_3$. Cyclic voltammetry reveals a monotonic shift in the onset of metal reduction kinetics towards positive potential and an increase in intensity of the additional peaks associated with Zr-Al alloy formation with increasing $AlF_3$ concentration. Unlike the galvanostatic deposition mode, a radial plate-type Zr growth is evident at the top surface of the salt during Zr electrorefining at a constant potential of -1.2 V. The diameter of the plate-type Zr deposit gradually increases with increasing $AlF_3$ concentration. Scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX) and X-ray photoelectron spectroscopy (XPS) analyses for the plate-type Zr deposit show that trace amount of Al is incorporated as Zr-Al alloys with different chemical compositions between the top and bottom surface of the deposit. Addition of $AlF_3$ is effective in lowering the residual salt content in the deposit and in improving the current efficiency for Zr recovery.

Carbon Footprint Analysis of Mineral Paper using LCA Method (전과정 평가기법을 활용한 미네랄 페이퍼의 탄소발자국 연구)

  • Kim, Byoung Jik;Kang, Seong Min;Lee, Jeongwoo;Sa, Jae Hwan;Kim, Ik;Jeon, Eui Chan
    • Journal of Climate Change Research
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    • v.4 no.3
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    • pp.201-210
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    • 2013
  • In recent years, with the rising interest to reduce greenhouse gas emissions, the demand for using environmentally friendly product with low greenhouse gas emission is increasing in the printing industry as well. In this study, the carbon footprint of environmentally friendly product mineral paper that uses less plastic and wood than normal printing paper materials was analyzed by utilizing the life cycle assessment (LCA) technique. An analysis utilizing the LCA technique was done per the Korea carbon footprint certification guidelines and, for scope of study, it included the premanufacturing stage and manufacturing stage except for the use and disposal stages. As a result of the study, the emission coefficient of the mineral paper was calculated to be $0.81kg\;CO_2eq/kg$ and the emission from electricity usage of the entire greenhouse gas emission was calculated to be 45.85% ($0.37kg\;CO_2eq/kg$). In order to reduce greenhouse gas emission, required are the efforts to reduce the environmental loads by using energies that have relatively lower environmental loads, such as improvement in electricity usage efficiency and renewable energy, by increasing product completion rates during the manufacturing process of mineral paper.

A Study on the GHG Reduction Newest Technology and Reduction Effect in Power Generation·Energy Sector (발전 에너지 업종의 온실가스 감축 신기술 조사 및 감축효과 분석)

  • Kim, Joo-Cheong;Shim, So-Jung
    • Journal of Climate Change Research
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    • v.4 no.4
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    • pp.349-358
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    • 2013
  • In this study, the newest technology available to reduce GHG emissions, which can be applicable in energy industries of the future that has large reduction obligations by energy target management and large intensity of GHG emissions, has been investigated by searching the technical characteristics of each technology. The newest technology to reduce GHG emissions in the field of power generation and energy can be mainly classified into the improvement of efficiency, CCS, and gas combined-cycle technology. In order to improve the reliability of the GHG emission factor obtained from the investigation process, it has been compared to the technology-specific GHG emission factor derived from the estimated amount of emissions. Then the GHG abatement measures, using the derived estimation of factor, by using the newest technology to reduce GHG emissions have been predicted. As a result, the GHG reduction rate by technology of CCS development has been expected to be the largest more than 30%, and the abatement rate by technology of coal gasified fuel cell and pressurized fluidized-bed thermal power generation has been showed more than 20%. If the effective introduction of the newest technology and the study of its characteristics is continued, and properly applied for future GHG emissions, it can be prospected that the national GHG reduction targets can be achieved in cost-efficient way.

Performance Evaluation of Aqueous Redox Flow Battery using Quinone Redox Couple Dissolved in Ammonium Chloride Electrolyte (염화암모늄 전해질에 포함된 퀴논 레독스 활물질 조합을 이용한 수계 레독스 흐름 전지 성능 평가)

  • Lee, Wonmi;Chung, Kun Yong;Kwon, Yongchai
    • Korean Chemical Engineering Research
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    • v.57 no.2
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    • pp.239-243
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    • 2019
  • In this study, anthraquinone-2,7-disulfonic acid (2,7-AQDS) is used as negative active material and Tiron is used as positive active material for aqueous redox flow battery (RFB). In previous results that used the 2,7-AQDS and Tiron, sulfuric acid ($H_2SO_4$) was a supporting electrolyte. However, in this study, ammonium chloride ($NH_4Cl$) is suggested as the electrolyte for the first time. By changing the supporting electrolyte from $H_2SO_4$ to $NH_4Cl$, the cell voltage of RFB is improved from 0.76 V to 1.01 V. To investigate the effect of $NH_4Cl$ supporting electrolyte of the performance of RFB, the full-cell tests of RFB using 2,7-AQDS and Tiron that are dissolved in $NH_4Cl$ supporting electrolyte are carried out, while cut-off voltage range is a main parameter to determine their performance. When the cut-off voltage range is 0.2~1.6 V, the hydrogen evolution occurs during charging step. To address the side reaction effect, the cut-off voltage range is changed to 0.2~1.2 V. When the revised cut-off voltage range is used and the current density of $40mA/cm^2$ is applied, hydrogen evolution is not observed and the optimal RFB shows the charge efficiency of 99% and discharge capacity of 3.3 Ah/L at 10cycle.

Properties of quasi-noncombustible ultra-lightweight geopolymer (준불연 초경량 지오폴리머의 물성)

  • Kim, Yootaek
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.29 no.3
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    • pp.132-139
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    • 2019
  • EPS (expanded polystyrene) is one of the most used building materials for insulation that is favored by its excellent heat insulation, economical efficiency and lightweight characteristics. However, EPS is vulnerable to the fire and producing large amount of toxic gases in case of fire. Therefore, ultra-lightweight geopolymer which can replace EPS is fabricated by using IGCC (integrated gasification combined cycle) fused slag and Si sludge as raw materials and the possibility of replacement on ultra-lightweight geopolymer for EPS as an insulation building material was evaluated in this study. Ultra-lightweight geopolymer can be fabricated with the pulverized IGCC fused slag having low carbon content and density, compressive strength, thermal conductivity were $0.064g/cm^3$, 0.04 MPa, and 0.072 W/mK, respectively. The thermal conductivity of ultra-lightweight geopolymer is 1.5~2.0 times higher than that of EPS suggested in the KS M 3808; however, the thermal conductivity value of geopolymer is meaningful and competitive to that of EPS in the market. Therefore, ultralightweight geopolymer can be applicable to the building material for thermal insulation purpose and have an enough possibility to replace EPS in the future because it is not only much safer than EPS in case of fire but also it can be fabricate by using waste materials from the industry.

Implications on the Technical Level of Industries and Industry-Academia Cooperation in Chungbuk Province (충북지역 산업체 기술수준과 산학협력에 관한 시사점)

  • Nam, Jae-Woo;Lim, Sung-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.7
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    • pp.520-527
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    • 2019
  • In this study, the technical level and competence of Chungbuk region manufactures were diagnosed and implications for efficiency improvement of cooperation with local universities were derived. The results are as follow. First, in Chungbuk area, 75% of the skilled workers are medium-skilled and high skilled workers. And the life cycle of production products was found to have entered middle/old age. In addition, the industries were overestimating its technology capabilities, including marketing and sales technology, and management technology. Therefore, local universities should develop differentiated program such as technology transfer and commercialization support so that companies can nurture new industries and it is necessary to improve understanding of reality and future prediction ability through various education and seminars. Second, universities in Chungbuk province have failed to meet the practical demands of industry by providing general educational programs such as lifelong education curriculum, rather than the practical training required by industry. First of all, industries needed the practical training programs such as human resource empowerment, technical education and workers' retraining for local industry development. In addition, industries were expected to provide relevant knowledge and infrastructure such as testing, analysis, participation in technology development such as commissioning and joint research. Therefore, universities should prepare customized Industry-Academia Cooperation Programs through industry demand survey in planning. Also, it is necessary to establish various connection points with industry to ensure that industry-academia cooperation will continue and achieve results. Third, the technology of the industries in Chungbuk province was found to be very unrelated to the next generation regional strategic industries. This is not shared vision between industry and local government, Industry-Academia Cooperation Programs will serve as a platform to organize various community entities. Universities will be able to play a key role in between industries and local governments.