• Journal of Powder Materials
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• v.9 no.5
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• pp.352-358
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• 2002

The effects of boron or manganese added as $B_4C$, Mn, $TiB_2$, B on TiC-30vo1.%$Ni_3Al$ cermet sintered at 1380 and $1400^{\circ}C$ for 1 hour, were examined in relation with shrinkage, relative density, microstructure, lattice parameter, hardness and fracture toughness ($K_{IC}$). The results are summarized as follows: 1) The highest shrink-age showed about 30.5% in the specimen added B$_4$C and the maximum relative density was about 99% in the specimen added $TiB_2$; 2) The grains of TiC were grown during sintering and made the surrounding structure by adding boron and manganese. The largest grain size showed about $2.8\mutextrm{m}$ in the specimen with boron sintered at $1400^{\circ}C$;3) The lattice parameter of TiC was about $4.325\AA$ and $Ni_3Al$ about $3.592\AA$ by adding other elements; 4) The highest hardness was about $1100kgf/\textrm{mm}^2$ in the specimen with B4C; 5) The fracture toughness ($K_{IC}$) showed about $15MNm^{-3/2}$ in the specimen added $TiB_2$.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.9
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• pp.497-503
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• 2016

Eco-friendly biocide that do not have noxious chemicals, have a role of disinfection adding of dispersion and strengthening peer power on RO membranes surfaces. Eco-friendly biocide show an 93% improvement of differential pressures arrival time. Also, eco-friendly biocide's Autopsy result show less the percentage of organic pollutants than currently in using biocide. Adding dispersion & peeling strength power to remove the microorganisms is upgrading. Eco-friendly biocide that have a dispersion and peering power is non-toxicant chemicals and is safe for user.

• Journal of Korea Foundry Society
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• v.8 no.3
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• pp.271-281
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• 1988

Al-bronze has a good mechanical property, corrosion resistance and castability, so being highlighted for the new copper alloy. So, effects of alloy composition and cooling rate in the mechaincal properties and solidification behavior have been investigated. The results obtained are as follows; 1) Change in volume on solidification is larger in metal mold casting than in sand mold casting. And it decreases by the addition of Al. 2) The mechanical property in metal mold casting is superior to the one in sand mold casting, and the inclination is obvious up to 9% Al, after heat-treatment ($885^{\circ}C$, $1.5hrs\;{\rightarrow}\;W\;{\cdot}\;Q\;{\rightarrow}\;540^{\circ}C$, 3hrs) 3) By adding Al, the mechanical property is slightly increased up to 9% Al, Above 9% Al, it is increased rapidly, and is accelerated by adding Fe. 4) Cooling rate and hardness, and grain size and cooling rate are related as follows in the range of $1100^{\circ}C$ to $1200^{\circ}C$ pouring temperature. Grain size(${\mu}m$)=$929.6422{\times}cooling\;rate(^{\circ}C\;/\;sec)^{-0.51537}$ Hardness(BHN)=$765.45713{\times}grain\;size({\mu}m)^{-0.31058}$.

• Journal of the Korean Vacuum Society
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• v.8 no.4B
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• pp.524-529
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• 1999

We deposited diamond phase carbon thin films on Si substrate by the electrolysis of methanol solution. A little amount of ammonia solution was added to increase the current density of the electrolyte. We analyzed films by XRD and SEM. The chemical change of electrolyte during the electrolysis process was characterized by FTIR. We obtained better quality diamond phase carbon films at a lower applying boltage(300V) and temperature ($40^{\circ}C$) by adding ammonia solution to methanol electrolyte. Diamond (111), (220), (311) peaks were shown distinctively in XRD graph. Addition of ammonia solution resulted in lowering the applying bias voltage to 300V and the substrate temperature to $40^{\circ}C$ still maintaining a high current density at 80mA/$\textrm{cm}^2$, which prohibited a great loss of solution from vaporization. Possible change of chemical reaction due to the addition of ammonia solution was also discussed.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.293-296
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• 2011

This survey was conducted to promote the environment-friendly use and recycling of livestock feces by obtaining information about the current state of livestock feces composts manufactured in Gyeonggi Province. Therefore, some aspects of quality and manufacturing techniques of livestock feces composts (LFCs) were examined especially in relation to the LFCs quality standard (LQS). By surveying the 70 composting plants in Gyeonggi Province, the total commercial production of LFCs in 2008 was estimated to be about $480,000Mg\;year^{-1}$ and they were manufactured mainly by using both mechanical mixer and bottom air blower. LFCs were composed mainly of chicken feces 29.2%, pig+chicken feces 23.1%, pig feces 20.0%, livestock feces+oil cake 12.3%, pig+chicken+cattle feces 10.8% and pig+cattle feces 4.6%. On the basis of the current official standard which was revised on March 2010, 11 composts out of surveyed 76 ones did not meet the LQS due to inadequate content of water (5), OM/N (1), NaCl (2) and Zn (3). The satisfaction rate to LQS by manufacturers was 100% in the composts produced by farmer's cooperative societies, 80.7% by civil factories, and 44.4% by farming guilds, respectively. The OM/N declined by adding chicken feces and oil cake, while Ca content was increased by the addition of chicken feces and NaCl was increased by adding cattle feces.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.9
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• pp.104-110
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• 1998

This paper proposes a architecture of the nonlinear echo canceller for the full-duplex transmission, which is easy to implement. The architecture is designed to cancel the nonlinear echo signals due to the hybrid or the data converter, as well as the linear echo signals, by adding a small number of taps to the FIR structure for the linear echo cancellation. The number of tap to be add depends on how much the linear echo signals are cancelled. A computer program for this architecture was written and run. Numerical results of the computer simulations show good performances on cancellations of the nonlinear echo signals by adding a small number of taps.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.53-56
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• 2010

In this study, we conducted an impact assessment of the amount of volatile organic solvents addition on hybrid water-proofing system of urethane waterproof coating material and modified asphalt sheet. Also, we conducted a comparative assessment of whether modified asphalt sheet is dissolved or not and oil leakage by dissolution in order to perform a comparative analysis of characteristics of the impact on modified asphalt sheet according to the volatility of volatile organic solvents included in urethane waterproof coating material. The test was carried out by adding the same amount of organic solvents into each experimental group which is subject to volatility and non-volatility of organic solvents, respectively. The results of the test showed that in both experimental groups modified asphalt sheet was dissolved when adding over 10 percent of organic solvents regardless of volatility, and oil leakage observed only in the experimental group subject to volatility.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.233-240
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• 1991

Effects of various sub-ingredients (hot pepper, garlic, ginger, green onion, leek, salted and fermented anchovy juice, and sugar) on the sensory quality of Korean cabbage kimchi were investigated. Sixteen sensory attributes were selected and their intensities evaluated by 20 panelists. The kimchi had an unbarmonized taste and unpleasant flavor when fermented with individual sub-ingredients, but had a well harmonized taste when fermented with all sub-ingredients. Hot pepper, ginger and garlic contributed to reduction of the unpleasatnt taste and moldy odor. The strong garlic flavor was reduced by adding green onion and leek. Salted and fermented anchovy juice gave a palatable taste, and the overall taste was improved by adding sugar. All sub-ingredients except sugar reduced the sour tasts.

• The Journal of Korean Academic Society of Nursing Education
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• v.15 no.2
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• pp.311-320
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• 2009

Purpose: This study was done to investigate the factors associated with a mothers' caring behavior in health promotion of children with disabilities. Methods: Data were collected by using self-reported questionnaires from 371 mothers who had a 3-12 year old child with a disability from July 14 to 31, 2008. Data were analyzed by descriptive statistics, t-test, one-way ANOVA, and hierarchical multiple regression analysis with the SPSS program. Results: There were significant differences on the mothers' caring behavior according to children's negative and hyperactive behavior, mothers' perceived burden, parenting efficacy, and social support. Children's characteristics explained 5.1% of mothers' caring behavior. The power of explanation ($R^2$) was 16.6% by adding mother's characteristics including mother's job, burden, parenting efficacy, satisfaction and stigma, and increased to 23.5% by adding social support. Conclusion: These results showed that mothers' caring behavior for their children's health promotion could be influenced by children's behavior problems, mothers' perception of burden, parenting efficacy, and social support. It suggests that health promotion programs for children with disabilities should focus on lowering subjective burden and enhancing mother's efficacy as a type of social support.

• Herbal Formula Science
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• v.17 no.1
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• pp.85-98
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• 2009

In the oriental medicine, the Persicae Semen is a useful material for promoting blood circulation through removement of the extravasated blood in a blood vessel. This study is based on Dongueibogam, which has been widely used for herbal clinic in Korea. And this study is investigated to make sure of the range of Persicae Semen treatment, the nature of disease, the pathology and the dosage of it in Dongueibogam. The following conclusions were reached through investigations on the main prescriptions that used in Dongueibogam as a key ingredient. 1. The prescriptions of blending with the Persicae Semen are utilized in 25 fields of treatments such as feces, uterus, blood diseases, etc. 2. The Persicae Semen is used in the treatment of constipation, removement of blood stasis of gynecology. 3. The average mass of the Persicae Semen is 0.352g, the standard limited range of adding the Persicae Semen to medical prescription is 0.5$\sim$40g or 6$\sim$40pieces per dose. But, in most case of treatment medicines, an typical and regular adding dose is the range of 2$\sim$4g. 4. The Persicae Semen is one of basic materials for a fundamental prescription among several herbal remedies for the pathology.