• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2000.11a
• /
• pp.147-152
• /
• 2000

This paper presents the thermoelastic analysis and 3-D failure analysis of the carbon/carbon brake disk. The mechanical properties of the carbon/carbon brake disk were measured for both in-plane and out of plane directions. The mechanical properties were used as the input of the thermoelastic analysis and 3-D stress analysis for the brake disk. The gap between rotor clip and clip retainer was an important parameter in the loading transfer mechanism of the rotor. The change of gap was considered separating the mechanical deformation and thermal deformation. Because the rotor clip and clip retainers were not contacted, the clip retainers and rivets were excluded from the rotor analysis model. The disk was modeled by using the cyclic symmetry condition and the contact problem between the rotor disk and rotor clip was considered. From the results of the 3-D stress analysis, the stress concentration at the key hole of the brake disk was confirmed.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.65 no.3
• /
• pp.1-13
• /
• 2023

Local governments play a critical role in achieving carbon neutrality and reducing national carbon emissions. To manage carbon emissions effectively, it is essential for local governments to analyze regional carbon emissions. In this study, we developed a model for estimating carbon emissions based on land use and analyzed regional characteristics of carbon emissions to suggest policies for achieving carbon neutrality at the regional level. Our model for calculating carbon emissions is based on an analysis of the activities that contribute to carbon emissions for each land use, and we established the spatial scope of carbon emission calculation. We applied this model to the cities and counties in Gyeongsangnam province, calculating carbon emissions from settlement and agricultural production activities and comparing regional characteristics of carbon emissions. Our analysis showed that areas with larger populations generally produced higher emissions in all categories, but we observed different results in terms of unit emissions, emissions divided by area, population, and household. Based on these findings, we propose policies such as increasing the generation of new and renewable energy using public institutions, promoting the conversion to cleaner cooking and heating energy sources, and encouraging the adoption of eco-friendly automobiles on roads. We believe that our analysis of the spatial and regional characteristics of carbon emissions can help local governments establish effective policies for reducing carbon emissions in their regions.

• Korea Trade Review
• /
• v.44 no.1
• /
• pp.45-56
• /
• 2019

The purpose of this study is to investigate the relationship between foreign investment and carbon emissions in the Korean electricity sector, the causal relationship between the foreign investment invested in the electric power sector in the 16 regional regions and the carbon emissions in the region, The purpose of this study is to analyze the effects of foreign investment on these sectors and the carbon footprint of these sectors using Panel Random Effect Analysis, Panel VAR and OLS models. A panel analysis of foreign investment and regional carbon emissions showed that there was a causal relationship. Based on this analysis, OLS analysis showed that 7 out of 16 metropolitan areas were foreign investment And carbon emissions were significant. In the remaining six regions except Gwangju, there was a causal relationship between foreign investment in the local power sector and the reduction of carbon emissions. After categorizing the electric power industry by device, process, purpose and number of employees, causality also appeared in relation to foreign investment in these sectors and their carbon emissions. Through this study, the authors suggest that foreign investment can be a way to solve not only the financial burden of carbon emission problem, but also the development of national economy and industry through the inflow of capital and advanced new technology.

• Korean Journal of Organic Agriculture
• /
• v.30 no.3
• /
• pp.375-391
• /
• 2022

This study investigated the online transaction status of low-carbon certified fresh agricultural products and analyzed the low-carbon certified premium. For two months from March to April 2022, eight products (rice, apple, pear, sweet persimmons, paprika, tomatoes, cherry tomatoes, and lettuce) were surveyed at major online shopping malls. The low-carbon certification premium was analyzed using hedonic price analysis model. As a result of the online market survey, the low-carbon certified agricultural products were not traded in the case of rice, cherry tomatoes, and paprika. And the proportion of low-carbon certified agricultural products in the case of tomatoes and lettuce was low. As a result of the low-carbon premium analysis, of the five products that analyzed the low-carbon certification premium, four products excluding pear did not have a low-carbon certification premium. Thus, it is necessary to expand the sale of the low-carbon certified agricultural products by distributors, and various efforts to secure the premium of certified agricultural products are important.

• Journal of Sensor Science and Technology
• /
• v.29 no.2
• /
• pp.128-132
• /
• 2020

Total organic carbon (TOC) analysis equipment, which was previously used to prevent eutrophication in advance, is heavy, bulky, and expensive; therefore, so it is difficult to be carried and has been used as an experimental unit. In this study, a through-carbon analysis chip that integrates pretreatment through photocatalytic oxidation and carbon dioxide measurement using a pH indicator was investigated. Both the total carbon - inorganic carbon method and the nonpurgeable organic carbon (NPOC) measurement method require an acidification part for injecting an acid solution for inorganic carbon measurement and removal, an oxidation part for total carbon or NPOC oxidation and a measurement part for Carbon dioxide (CO₂) measurement. Among them, the measurement of oxidation and CO₂ requires physical technology. The proposed TOC analysis chip decomposed into CO₂ as a result of the oxidizing of organic carbon using a photocatalyst, and the pH indicator that was changed by the generated CO₂ was optically measured. Although the area of the sample of the oxidation part and the pH indicator of the measurement part were distinguished in an enclosed space, CO₂ was quantified by producing an oxidation part and a measurement part that shared the same air in one chip. The proposed TOC analysis chip is less expensive and smaller, cost and size are disadvantages of existing organic carbon analysis equipment, because it does not require a separate carrier gas to transport the CO₂ gas in the oxidation part to the measurement part.

• Elastomers and Composites
• /
• v.27 no.2
• /
• pp.89-101
• /
• 1992

This paper is concerned with analysis for market trend and technological tendency of rubber-use black among United state, Japan and Korea, Through this comparative analysis, the subjects with which domestic carbon black industry is confronted are : first, development of new grade carbon black such as high performance carbon black, Low rolling resistance carbon black and lower grit carbon black, Second, reduction of quality fluctuation, third, improvement of applied technology and fourth, strengthening the price competitiveness through process optimization and productivity increase.

• Carbon letters
• /
• v.26
• /
• pp.11-17
• /
• 2018

Milled carbon fiber (mCF) was prepared by a ball milling process, and X-ray diffraction (XRD) diffractograms were obtained by a $2{\theta}$ continuous scanning analysis to study mCF crystallinity as a function of milling time. The raw material for the mCF was polyacrylonitrile-based carbon fiber (T700). As the milling time increased, the mean particle size of the mCF consistently decreased, reaching $1.826{\mu}m$ at a milling time of 18 h. The XRD analysis showed that, as the milling time increased, the fraction of the crystalline carbon decreased, while the fraction of the amorphous carbon increased. The (002) peak became asymmetric before and after milling as the left side of the peak showed an increasingly gentle slope. For analysis, the asymmetric (002) peak was deconvoluted into two peaks, less-developed crystalline carbon (LDCC) and more-developed crystalline carbon. In both peaks, Lc decreased and $d_{002}$ increased, but no significant change was observed after 6 h of milling time. In addition, the fraction of LDCC increased. As the milling continued, the mCF became more amorphous, possibly due to damage to the crystal lattices by the milling.

• International conference on construction engineering and project management
• /
• 2017.10a
• /
• pp.14-23
• /
• 2017

In high-density high-rise cities such as Hong Kong, buildings account for nearly 90% of energy consumption and 61% of carbon emissions. Therefore, it is important to study the design of buildings, especially high-rise buildings, to achieve lower carbon emissions in the city. The carbon emissions of a building consist of embodied carbon from the production of construction materials and operational carbon from energy consumption during daily operation (e.g., air-conditioning and lighting). An integrated analysis of both types of carbon emissions can strengthen the design of low carbon buildings, but most of the previous studies concentrated mainly on either embodied or operational carbon. Therefore, the primary objective of this study is to develop a holistic methodology framework considering both embodied and operational carbon, in order to enhance the sustainable design of low carbon high-rise buildings. The framework will be based on the building information modeling (BIM) technology because BIM can be integrated with simulation systems and digital models of different disciplines, thereby enabling a holistic design and assessment of low carbon buildings. Structural analysis program is first coupled with BIM to validate the structural performance of a building design. The amounts of construction materials and embodied carbon are then quantified by a BIM-based program using the Dynamo programming interface. Operational carbon is quantified by energy simulation software based on the green building extensible Markup Language (gbXML) file from BIM. Computational fluid dynamics (CFD) will be applied to analyze the ambient wind effect on indoor temperature and operational carbon. The BIM-based framework serves as a decision support tool to compare and explore more environmentally-sustainable design options to help reduce the carbon emissions in buildings.

• Nuclear Engineering and Technology
• /
• v.49 no.4
• /
• pp.873-880
• /
• 2017

To identify the feasibility of disposing of spent activated carbon as a clearance level waste, we performed characterization of radioactive pollution for spent activated carbon through radioisotope analysis; results showed that the C-14 concentrations of about half of the spent activated carbon samples taken from Korean NPPs exceeded the clearance level limit. In this situation, we selected thermal treatment technology to remove C-14 and analyzed the moisture content and thermal characteristics. The results of the moisture content analysis showed that the moisture content of the spent activated carbon is in the range of 1.2-23.9 wt% depending on the operation and storage conditions. The results of TGA indicated that most of the spent activated carbon lost weight in 3 temperature ranges. Through py-GC/MS analysis based on the result of TGA, we found that activated carbon loses weight rapidly with moisture desorption reaching to $100^{\circ}C$ and desorbs various organic and inorganic carbon compounds reaching to $200^{\circ}C$. The result of pyrolysis analysis showed that the experiment of C-14 desorption using thermal treatment technology requires at least 3 steps of heat treatment, including a heat treatment at high temperature over $850^{\circ}C$, in order to reduce the C-14 concentration below the clearance level.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.31 no.5
• /
• pp.416-424
• /
• 2007

In adsorption/catalytic process, numerical analysis has been performed to identify the flow characteristics of flue gas in the cyclone and to estimate the residence time of activated carbon using Computational Fluid Dynamics (CFD) technique. To consider flue gas and activated carbon particles simultaneously, Euler-Lagrangian model was employed so that residence time could be obtained from the numerical analysis directly. The numerical analysis has been performed with different three particle sizes and compared each flow characteristics with particle’ size. Fundamental flow patterns of flue gas and activated carbon particles, pressure distribution, residence time of flue gas, and activated carbon particles and distribution of activated carbon have been obtained from the numerical analysis.