• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.571-573
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• 1995

This paper presents a method for optimal dispatch which minimizes transmission losses and improves voltage profile of power systems using genetic algorithm based on the mechanism of natural genetics and natural selection. The constraints are VAR sources(transformer tap, generator voltage magnitude and shunt capacitor/reactor), load bus voltages and generator reactive power. Real variable-based genetic algorithms which can save coding times and maintain the accuracy are applied for optimal dispatch of reactive power. The genes of genetic algorithm consisted of integers for considering discrete VAR sources. A efficient operator for crossover is proposed to consider the effect of close genes. The algorithm proposed can apply to problems for large scale power systems with multi-variables and complex nonlinear functions efficiently. The proposed method is applied to IEEE 30 buses model system to show its effectiveness.

• Journal of Wetlands Research
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• v.1 no.1
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• pp.1-5
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• 1999

We could know that the Woopo and Mokpo wetlands, which have the typical colony structure in the agricultural area of korea, had a characteristic which the pollution sources of water are scattered widely and it is caused by sewage, livestock wastewater and non point sources. As the result of an examination of water, the concentration of T-N was measured highly within five grade in the lake standard. If we build natural domestic treatment system in Taehap-myon, lbang-myon and Yuo-myon, which are located at the upper stream of wetlands, we can remove SS, BOD, COD and T-N largely.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.373-381
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• 2023

This study aimed to isolate and characterize wild yeast strains from the vineyard soil in Korea. Twenty yeast strains were isolated from vineyard soil in Gimpo-si, Gyeonggi-do, Korea, where Vitis labrusca cv. Campbell Early is grown. Eighteen strains were previously recorded in Korea. The remaining two, Cyberlindnera mrakii VG-21-10C and Starmerella bacillaris GR9 were not previously recorded in Korea. The mycological characteristics of VG-21-10C and GR9 were investigated. Both were oval-shaped, convex, and smooth. However, differences were evident in colony color and carbon assimilation activities. Strain VG-21-10C is white-colored and assimilates glucose, glycerol, D-xylose, D-cellobiose, D-saccharose, and D-raffinose as carbon sources. Strain GR9 is cream-colored and assimilates glucose, D-saccharose, and D-raffinose as carbon sources.

• Korean Journal of Oriental Medicine
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• v.1 no.1
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• pp.471-476
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• 1995

Natural products used for oriental medicine often come from various geographical sources, after several different distribution channels. Therefore some form of quality control procedure is required to safeguard naturl products for prescriptions purposes. To achieve this, systematic apprroaches such as morphological examination, microscopic analysis of powdered herbs and chemical analysis can be carried out. However, to ensure absolute criteria for quality assurance of natural products, DNA fingerprinting method such as RAPD(Random amplified polymorphism DNA) analysis can be used for authentication of natural products for authenticatin of natural products. In this study, warious oligonucleotide primers will be synthesized for the detection of RAPD markers and also parameters of affecting PCR(Polymerase Chain Reaction) in the detection of RAPD markers of rare and high-priced natural products will be studied with genomic DNA of chosen samples.

• Journal of Power System Engineering
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• v.13 no.2
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• pp.5-10
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• 2009

In recently, studies concerned to the diesel engine uses a natural gas as a fuel oil whose infra has been built already was approached to PCCI or HCCI with keeping a high thermal efficiency and reducing NOx and PM have been researching actively in normally single cylinder. An ignition source is required to bum the natural gas by a spark plug in gasoline engines, due to a higher auto-ignition temperature of natural gas. Then gas oil and DME were introduced as the ignition source. In this study as basic data for practical use of natural gas PCCI and HCCI engines, combustion characteristics and emission characteristics on 4-cylinders natural gas PCCI and HCCI engines with gas oil and DME as ignition sources were analyzed and the engine load range that is main object for practical use of PCCI and HCCI engines was made clearly by empirical experiment.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.499-500
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• 2003

To investigate the potency of some natural extracts as skin whitening agents, in this study, 25 natural plants were prepared from natural sources including medicinal plants, such as Angelica dahurica using methylene dichloride, ethyl acetate, n-butyl alcohol, and water as the extraction and/or the partitioning solvents. These natural extracts were subsequently subjected to in-vitro DOPA auto-oxidation test in the media containing human or mushroom tyrosinase as the oxidation promoting enzymes. Most of the extracts showed relatively higher enzyme inhibition(omitted)

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.187-192
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• 1992

There are several potential error sources that can affect the estimation of the position of an object using combined vision and acceleration measurements. Two of the major sources, accelerometer dynamics and random noise in both sensor outputs, are considered. Using a second-order model, the errors introduced by the accelerometer dynamics are reduced by the smaller value of damping ratio and larger value of natural frequency. A Kalman filter approach was developed to minimize the influence of random errors on the position estimate. Experimental results for the end-point movement of a flexible beam confirmed the efficacy of the Kalman filter algorithm.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.1092-1095
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• 2000

Computer graphics(CG) is one of the most useful tools by which we can easily understand visible/invisible natural phenomena. Namely, phenomena in the universe is attractive one because of its beauty and invisibility on the earth. For gravitational tensing phenomena, a ray tracing algorithm is proposed based on a lens-plane. In the method, position of gravitational sources is restricted. In this paper an improved visualization method is proposed, which can represent more complex situation than the previous method.

• Advances in materials Research
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• v.2 no.2
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• pp.93-98
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• 2013

Objective of this study is to calculate gamma buildup factors for pointed and isotropic gamma sources in depleted uranium, uranium dioxide, natural uranium, tin, water and concrete using MCNP4C code. The thickness of the media ranges from 0.5 to 10 mean-free-path (mfp) and gamma energy ranges from 0.5 to 10 MeV. Owing to the outstanding accuracy of MCNP in calculation involving gamma interaction, results fairly match those reported previously. The maximum relative error is 2%.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.137-142
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• 2007

For the production of natural pigments with microbe, the strains which produced monascus pigment were isolated, and then culture condition and extraction condition were investigated. These results are summarized as follows; The strain which ran produce monascus natural pigment was isolated from natural microbial sources and we made mutant of this strain with UV($235_{nm}$, 30 second) irradiation. The mutant was identified as Monascus sp. MK2-2. The optimal culture conditions were investigated optimal medium containing 0.3% rice powder, 0.2% yeast extract, 0.3% $NH_4H_2PO_4$ and $30^{\circ}C$ in a rotary shaker (120 rpm) for 5 days (initial pH 5.0), while the pigment production was determined at 24 hr intervals. The effective carbon sources were wheat flour > rice powder > fructose, and effective nitrogen sources were sodium nitrate > $KNO_3$ for production of the monascus natural pigment. The pigment capacity is good from 17 to 22 in C/N ratio. The production amount of monascus natural pigment was 0.38 g per 1 kg of rice. Also, extract of red yeast rice had anti-thrombosis activity like a degree of aspirin.