• Journal of Korean Society for Atmospheric Environment
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• v.22 no.E2
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• pp.49-56
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• 2006

This pilot study focuses on emissions characterization of air pollutants produced from incineration of some municipal solid wastes (MSWs). The MSWs incinerated by an electric furnace maintained up to $600^{\circ}C$ included food, paper, and plastic wastes. The pollutants analyzed in this study included concentrations of volatile organic compounds (VOCs), bottom ash contents, and heavy metals extracted from the bottom ash of each waste. The VOCs identified were classified based on their chemical structure. The total emissions of VOCs produced from incineration of the papers were identified as the highest followed by those from the plastics and the food wastes. Aliphatic alkenes were major VOC compounds produced from incineration of plastic or food wastes, while furans were major VOCs produced from incineration of papers. The second major VOCs produced from incineration of food, plastics, and papers were aromatics. In particular, hazardous air pollutants such as benzene were produced with considerable amount of emission concentration. The bottom ash contents of papers were usually much higher than those of food or plastic wastes. The bottom ash contents produced from incineration of food and plastics were much lower than those of other MSWs. In analysis of heavy metals extracted by an ultrasonic method from the bottom ashes of the papers, high concentrations of heavy metals were identified from incineration of newspapers and box (cardboard). In addition, it was identified that the general public might be exposed to considerable amounts of lead concentrations during incineration processes and uses of paper cup and from ashes.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.4
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• pp.73-82
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• 2018

This research investigated the mechanical properties of the 4 different types of $3{\times}3$ cable stitches on weft knitted fabrics. The 4 kinds of cable-stitch fabrics were knitted under the same knitting conditions, then the mechanical properties, such as tensile strength, elongation, stiffness, etc. were measured according to the Korean Industrial Standards (KS K 0642). The knitting time for the sample produced by the knitting process 1 was the shortest among the 4 different types of samples. It means that the knitting process 1 would have benefits of higher productivity if there is no yarn breakage during the knitting of the cable stitches. In the test for tensile strength, the samples produced by knitting processes 3 and 4 have tensile values of approximately 8~11% higher than the sample produced by knitting process 1. The test for elongation also shows that the samples produced by knitting processes 3 and 4 have up to 18% higher elongation values than the sample produced by knitting process 1. On the other hand, the stiffness test showed no significant difference between the 4 samples. This study is expected to increase the competitiveness of the local knitting industry as a result of providing basic data on the mechanical properties of special knitted stitches, such as cable stitches.

• Journal of the Korean Ceramic Society
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• v.24 no.2
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• pp.133-138
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• 1987

The behavior of CaO and SiO2 in the reaction produced which produced in the early hydration of C3S was studied by XRD and thermal analyzer. Polymerization of hydrated siltcates was also studied by TMS method. TMS derivatives were separated by gaschromatography. Cao/SiO2 molar ratios of the produced CSH gel under the air atmosphere were higher than that in the CO2. Dimerization rate of hydrated silicates was very fast in the early hydration stage. Trimer began to appear later than dimer and its increasing rate was very low. The amount of dimer and trimer formed under the CO2 atmosphere was less than that in the air.

• Clean Technology
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• v.18 no.4
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• pp.446-450
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• 2012

Strong alkaline electrolyzed water which is produced in cathode by electrolyzing the solution where electrolytes (NaCl, $K_2CO_3$ etc.) are added in diaphragm electrolytic cell, is eco-friendly and has cleaning effects. So, it is viewed as a substitution of chemical cleaner. In addition, strong alkaline electrolyzed water is being used by some Japanese automobile and precision parts manufacturing industries. When strong alkaline electrolyzed water is produced by using diaphragm electrolytic cell, it is necessarily produced at the anode side. Since strong acidic electrolyzed water produced is discarded when its utilization cannot be found, production efficiency of electrolyzed water is consequently decreased. Also, there is a weakness electrolytic efficiency is decreasing due to the pollution of diaphragm. In order to overcome this, non-diaphragm all-in-one electrolytic cell integrated with electrode reaction chamber and dilution chamber was applied. Strong alkaline electrolyzed water was produced for different composition of electrolytes, and their properties and characteristics were identified. In comparing the properties between strong alkaline electrolyzed water produced in diaphragm electrolytic cell and that produced in all-in-one electrolytic cell, the differences in ORP and chlorine concentration were found. In emulsification test to confirm surface-active capability, similar results were obtained and strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell was identified to be useable as a cleaner like strong alkaline electrolyzed water produced in diaphragm electrolytic cell. Strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell is thought to have sterilizing power because it has active chlorine which is different from strong alkaline electrolyzed water produced in diaphragm electrolytic cell.

• Journal of Food Hygiene and Safety
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• v.10 no.1
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• pp.1-6
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• 1995

In order to establish the enzyme linked immunosorbent assay(ELISA) of sterigmatocystin produced by Aspergillus versicolor, we experimented and obtained following results. Two of three rabbits which had been immunized with sterigmatocystin-hemiacetal-BSA produced antibodies against sterigmatocystin at 15 weeks. The produced antibodies were specific for sterigmatocystin and sterigmatocystin-hemiacetal but didn't cross react with other sterigmatocystin analogues in a significant degree. DMF : 4% KC1 (18 : 2) mixed solution was most effective to dissolve sterigmatocystin. For the preparation of sample solution to determine sterigmatocystin by ELISA, sample was extracted with CHC13 and dried, than the dried sample was redissolved with 100 ${mu}ell$ DMF + 4% KC1 mixture. 10~1,000 ng/$m\ell$ level of standard sterigmatocystin could be applied to the established ELISA. When artifically contaminated rice were assayed by the ELISA, the average recovery of sterigmatocystin spiked to 25~500 ng/g was 109% (97~116%), and mean interwell coefficient of variation was 21% (11~28%).

• Speech Sciences
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• v.14 no.1
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• pp.93-103
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• 2007

The aims of this study were to examine the acoustic features of Korean and Japanese vowels, and to determine whether new phones that do not have counterparts in Japanese or similar phones that have counterparts improve more from learning. This study consisted of three parts. In Experiment I, a speech production test was performed to observe the acoustic features of Korean and Japanese vowels. In Experiment II, the speech production of Korean vowels produced by Koreans, advanced Japanese learners of Korean, and beginning Japanese learners of Korean was investigated. In Experiment III, a speech perception study of Korean vowels produced by the two Japanese learner groups was conducted to observe the effect of learning on acquiring L2 phones. The conclusion drawn from the study was that the similar phones produced by Japanese show more similarity with those of Koreans than new phones in terms of F1 and F2, but Japanese learners of Korean displayed more improvement in new phones from learning.

• Proceedings of the KSPS conference
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• 2006.05a
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• pp.101-104
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• 2006

The present study examined two acoustic characteristics(duration and intensity) of vowels produced by 4 cerebral palsic adults and 4 nondisabled adults in conversational and clear speech. In this study, clear speech means: (1) slow one's speech rate just a little, (2) articulate all phonemes accurately and increase vocal volume. Speech material included 10 bisyllabic real words in the frame sentences. Temporal-acoustic analysis showed that vowels produced by two speaker groups in clear speech(in this case, more accurate and louder speech) were significantly longer than vowels in conversational speech. In addition, intensity of vowels produced by cerebral palsic speakers in clear speech(in this case, more accurate and louder speech) was higher than in conversational speech.

• International Journal of Quality Innovation
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• v.2 no.2
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• pp.69-92
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• 2001

The laser-assisted seeding (LAS) process has potential to replace conventional electroless copper plating in Printed Circuit Board (PCB) manufacturing since it combines the steps of laser drilling and plating into one single process. In the LAS process, the single extra LAS step can metallize a microvia. Thus, the process steps can be greatly reduced and the productivity enhanced, but also the high aspect ratio microvias can be metallized. The objectives of this paper are to study the LAS copper thickness within PCB microvias and the thermal reliability of the microvias produced by this process. It was found that results were satisfactory in both the reliability test and also the LAS copper thickness which both comply with IPC standard, the copper thickness produced by the LAS process is sufficient for subsequent electro-plating process. The reliability of the microvias produced by LAS process is acceptable which are free from any voids, corner cracks, and distortion in the plated copper.

• Korean Journal of Materials Research
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• v.27 no.7
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• pp.374-380
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• 2017

Properties of coatings produced by warm spray were investigated in order to utilize this technique as a repair method for Al tire molds. $Al-(0-10%)Al_2O_3$ composite powder was sprayed on Al substrate by warm spraying, and the microstructure and mechanical properties of the composite coating layer were investigated. For comparative study, the properties of the coating produced by plasma spray, which is a relatively high-temperature spraying process, were also investigated. The composite coating layers produced by the two spray techniques exhibited significantly different morphology, perhaps due to their different process temperatures and velocities of particles. Whereas the $Al_2O_3$ particles in the warm sprayed coating layer maintained their initial shape before the spray, flattened and irregular shape $Al_2O_3$ particles were distributed in the plasma sprayed coating layer. The coating layer produced by warm spray showed significantly higher adhesive strength compared to that produced by plasma spray. Hardness was also higher in the warm sprayed coating layer compared to the plasma sprayed one. Moreover, with increasing the fraction of $Al_2O_3$, hardness gradually increased in both spray coating processes. In conclusion, an $Al-Al_2O_3$ composite coating layer with good mechanical properties was successfully produced by warm spray.

• Journal of the Korean Ceramic Society
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• v.35 no.9
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• pp.923-932
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• 1998

Al2O3/Al composites were produced by displacement reaction method which was carried out by imm-ersing the sintered silica preform which was prepared form fused silica powder in molten aluminu. an ac-tivation energy of 94kJ/mole was calculated from Al-SiO2 reaction data in 1000-130$0^{\circ}C$ temperature range With increase of reaction temperature the alumina particle in the Al2O3/Al composites produced with pur metal Al showed grain growth and the growth of alumina particle in Al2O3/Al composite produced by using of Mg contained Al alloy was inhibited. The flexural strength of Al2O3/Al composites produced at 100$0^{\circ}C$ showed the highest value as 393 MPa. Flexural strength of the composite fabricated at 85$0^{\circ}C$ showed higher deviation than that of the composite produced at above 100$0^{\circ}C$ Low flexural strength of the composite fa-bricated at 120$0^{\circ}C$ due to the growth of pore and alumina particle size. The hardness of composites de-pended on alumina content in Al2O3/Al composite decreased with increasing of aluminium content in case the same alumina content and increased with increasing of silicon content in composite.