• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.622-627
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• 2009

Using an alkali-solution developable photosensitive resin and a carbon black as a conductive filler, photo-patternable pastes for polymer thick film resistor were fabricated and evaluated. A photo solder resist (PSR), which is usually used as protecting layer of printed circuit board (PCB), was used as a photosensitive resin so that ultraviolet exposure and alkali-aqueous solution development of paste were possible. After fabricating the photosensitive polymer resistor paste, the electrical properties of thick film resistors were measured using PCB test boards. Sheet resistance was decreased with increasing amount of carbon black, but the developability was limited in excess loading of carbon black. The sheet resistance was also reduced by re-curing and the change rate was smaller in higher carbon black loading. Moreover, finely patterned meander-type thick film resistors were fabricated using photo-process and large resistance up to several tens of sheet resistance could be obtained in small area by this technique.

• Journal of Environmental Science International
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• v.24 no.6
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• pp.709-720
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• 2015

After analyzing the actual acquisition status of carbon labeling by year and by product for the past four years, as well as its certification in the construction-related sectors of greenhouse gas emission, this study attempted to present the problems and coping strategies upon issuing the carbon labeling certification in the landscape architecture. During the period of this analysis, the carbon labelings were acquired by 134 enterprises, 267 workplaces, and 735 products, while the percentage of acquisition was highest in the regular non-durable goods(49%), followed by energy-consuming durable goods(26%), regular production goods (19%), regular durable goods(3%), and service(3%). Furthermore, the acquisition certifications in construction sectors, were highest in the various pipes/panel(8 cases), followed by concrete(6 cases), gypsum board(4 cases), and landscape architecture materials(2 cases). The landscape architecture only had two cases in the acquisition certification for the first time in 2012, which accounted for 0.27% of the entire certification products, due to the uncertainty in the process, the lack of professionalism, and the lack of comprehension. However, the study conducted on the coping strategies for carbon labeling in the landscape architecture revealed the following: (1) regular reporting system management through the division of labor in the head office and factories, (2) the building of objective DB through the adoption of data management programs such as SAP, (3) continuous promotion and vitalization of the incentive system, (4) the adoption of mandatory or preferential application system in landscaping projects, management, and bidding, (5) enhancement of elasticity in deliberation of certification by recruiting experts in the landscape architecture sectors, and (6) provision of incentives for the cooperative firms acquiring the certification and support for their participation.

• Journal of the Korean Society of Safety
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• v.17 no.1
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• pp.61-67
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• 2002

The toxic gases released from a fire can be classified as asphyxiants such as carbon monoxide, and irritants such as hydrochloric acid, etc. It is recognized that the combustion characteristic of interior upholstery is one of the important factors to determine the severity of indoor fires. In this study, several of the mostly used interior upholsteries including wallpaper, veneer board, curtain and floor cover, were selected to be evaluated by using the method of NES 713. The toxicity indices of the experimental samples, which indicate their toxic potentials in a fire were lowered in the order of Wallpaper (Flame Retardant) 8.5>Floor Cover(Hard) 4.8>polyurethane 4.3>Floor Cover(Soft) 3.5>PVC 2.8> Veneer Board 2.3> Floor Cover(flame retardant) 2.1>Wallpaper(Promulgation) 1.4>Curtain 0.9. It is concluded that, among all the tested upholsteries, wallpaper (flame retardant) would release the largest quantity of Toxic gases in a fire.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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• pp.28-35
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• 2015

This paper introduces a resistance scanning-type flexible tactile sensor for intelligent robots and presents the output characteristics of the sensor via signal processing. The sensor was produced via the lamination method using multi-walled carbon nanotubes (a conductive material), an insulator, and Tango-plus (an elastic material). Analog and digital signal processing boards were produced to analyze the output signal of the sensor. The analog signal processing board was made up of an integrator and an amplifier for signal stability, and the digital signal processing board was made up of an IIR filter for noise removal. Finally, the sensor output for the contact force was confirmed through experiments.

• Journal of the Korean Institute of Rural Architecture
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• v.22 no.4
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• pp.71-78
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• 2020

Today, the whole world is going through a big chaos due to the COVID-19, but paradoxically, the emergence of COVID-19 has been leading to the need for sustainable development, such as Green New Deal that can improve global warming and carbon emissions, and the need for sustainable architecture is growing bigger and bigger in the architectural field as well. The level of CLT buildings in Korea is at a very rudimentary stage, while CLT buildings remedying existing wooden buildings are getting the spotlight among European countries for sustainable architecture. This study was conducted to categorize structure layer compositions of overseas CLT buildings and analyze architectural techniques and materials applied by collecting and analyzing information about CLT structure layer compositions of overseas CLT building-related institutions, companies and cases. When classifying structure layer compositions of foreign CLT buildings depending on the roles of layers. it was revealed that exterior wall structure layers were combined and organized within a sequence of external finishing, ventilation, waterproof, board, external insulation, airtightness, structure, airtightness, interior insulation, interior finishing, sloped roof structure layers were external finishing, ventilation, waterproof, board, external insulation, airtightness, structure, airtightness, interior insulation, interior finishing, flat roof structure layers were external finishing, ventilation, waterproof, planking wood, external insulation, waterproof, external insulation, airtightness, structure, airtightness, interior insulation, interior finishing.

• Clean Technology
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• v.18 no.4
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• pp.440-445
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• 2012

15 carbon footprint product (CFP) schemes, including Korea Carbon Footprint Label, UK Carbon Trust's Carbon Reduction Label and Japan CFP are implemented in the world. A CFP describes green house gases (GHGs) emissions emitted throughout product's life cycle and is intended to reduce GHGs emissions by labeling a CFP result on product. This study calculates Korea, UK and Japan CFP result of vacuum cleaner, detergent, packagin material in order to analyze the Korea, UK and Japan CFP standards. Our results demonstrate significant differences among then calculated results because of criteria, emission factors, etc. Therefore, there are many difficulties in providing various CFP results and the international standard and guidelines for product category are needed.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.115-120
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• 2002

Woodceramics are new porous carbon materials obtained by burning wood or woody materials impregnated with thermosetting resin in a vacuum furnace. In this paper, the change of dimensions and bending strength of woodceramics which were made from medium density fiberboard have been investigated to examination the possibility of utilization as a woodceramics materials. 1) An increasing rate of dimension in impregnated board increased with increasing resin impregnation rate. And increasing rate of thickness was higher than that of length. 2) When the resin impregnation rate increased, the bending strength of impregnated board had a tendency to increase. 3) The rates of weight loss, length and thickness reduction of woodceramics showed a slight increase with increased burning temperature. 4) The density of woodceramics showed a increase from at 500℃ till at 800℃ with increasing burning temperature but decrease at 1,000℃ 5) When the burning temperature increased, the bending strength of woodceramics had a tendency to increase.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.411-416
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• 2010

In this research, we intended to improve the tolerance of thick film resistor using photosensitive polymer resistor paste which was fabricated with alkali-solution developable photosensitive resin and conductive carbon black. At first, we investigated the effect of the selection of carbon black and photosensitive resin on the resistance range and tolerance level of polymer thick film resistor (PTFR). And then, a difference in resistance tolerance was evaluated according to the coating methods of photosensitive resistor paste on test board. In case that the photosensitive resistor paste was coated on whole surface of test board using screen printing, large positional tolerance was obtained because the formation of the thick film with uniform thickness was difficult. On the other hand, when the paste was coated with roller, the resistive thick film with uniform thickness was formed on the whole board area and the result of resistance evaluation showed low tolerance in ${\pm}10%$ range. The tolerance of PTFR could be improved by combination of the precise patterning using photo-process and the coating process for the resistive thick film with uniform thickness.

• Asian Journal of Atmospheric Environment
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• v.11 no.2
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• pp.107-113
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• 2017

This study describes (1) the impact of positive sampling artifacts caused by not only a filter-based sampling, but also a denuder-based sampling in the determination of particle-phase organic carbon (POC), (2) the effect of sample flow rate on positive artifacts, and (3) an optimum flow rate that provides a minimized negative sampling artifact for the denuder-based sampling method. To achieve the goals of this study, four different sampling media combinations were employed: (1) Quartz filter-alone (Q-alone), (2) quartz filter behind quartz-fiber filter (QBQ), (3) quartz filter and quartz filter behind Teflon filter (Q-QBT), and (4) quartz filter behind carbon-based denuder (Denuder-Q). The measurement of ambient POC was carried out in an urban area. In addition, to determine gas-phase OC (GOC) removal efficiency of the denuder, a Teflon filter and a quartz filter were deployed upstream and downstream of the denuder, respectively with varying sample flow rates: 5, 10, 20, and 30 LPM. It was found that Q-alone sampling configuration showed a higher POC than QBQ, Q-QBT, and Denuder-Q by 12%, 28%, and 23%, respectively at a sample flow rate of 20 LPM due to no correction for positive artifact caused by adsorption of GOC onto the filter. A lower quantity of GOC was collected from the backup quartz filter on QBQ than that from Q-QBT. This was because GOC was not in equilibrium with that adsorbed on the front quartz filter of QBQ during the sampling period. It is observed that the loss of particle number and mass across the denuder increases with decreasing sample flow rate. The contribution o f positive arti facts to POC decreased with increasing sample flow rate, showing 29%, 25%, and 22% for 10, 20, and 30 LPM, respectively. The 20 LPM turns out to be the optimum sample flow rate for both filter and denuder-based POC sampling.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.98-103
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• 2017

In this study, contributes to improving the state of this problem using cavitation by ultrasonic energy to reduce fuel costs, which take up a considerable part of ship operation costs, by making the use of on-board blended fuel oil more stable. An experiment simulating on-board blending methods was completed. Fuel (M.G.O & MF-180) was mixed at a volume ratio of 0.25:0.75 and, 0.75:0.25, and the effect of ultrasonic energy on blended fuel oil was examined after applying ultrasonic energy to blended fuel oil using an ultrasonic treatment unit. With the results, we confirmed the blending problem reported by vessels and residual carbon was reduced by up to 28.4%. In addition, based on the results for reduction of residual carbon content and dispersion stability, it was confirmed that the collapse pressure of the cavity due to the ultrasonic energy was effective to atomization of fuel particle and the temporary availability of mixed fuel containing a heavy fuel increased.