• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.5
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• pp.337-342
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• 1989

Since the late 1960s, the selection of the parameters of power system stabilizer (PSS) to damp out sustained low frequency oscillation of power generators in the steady state has been an active research area. This paper presents a new approach to select the optimal PSS parameters using the sensitivity of the quadratic performance with respect to the PSS parameters. The proposed algorithm has been applied to Seo-Cheon fossil power plant.

• New & Renewable Energy
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• v.7 no.3
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• pp.83-91
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• 2011

The purpose of this study is to select appropriate location factors for wind power plant, provide detailed classification criteria, and find out appropriate sites for installing wind power plant in Gangwondo. In this study, the following 11 factors were extracted for site selection of wind power plant : wind resource, topography (valley angle, distance to the ridge), forest density, land use, preservation area, national park, Baekdu-Daegan, noise, shade, Transmission Line, and approaching roads. Each factor had relatively different level of importance so that AHP (Analytic Hierarchy Process) technique was used to calculated the weighted value per factor. For overlay analysis, classification criteria were prepared for each factor and each factor was classified into 3 grades : very appropriate, intermediate, poor. According to overlay analysis, the areas which received the highest grade (grade 5) was only in 0.16% of the total area of Gangwondo and had a tendency to exist along the mountain ridge over 600-meter elevation. Through analyzing the yearly average of wind power density, it was proved that the wind power density of areas with grade 4 or 5 had abundant wind resource over $400W/m^2$.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.103-108
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• 1998

The Canadian production of American ginseng (Panax quinquefolius L.) occurs mainly in Ontario, British Columbia and the Atlantic provinces. Although ginseng is a profitable crop, its successful production is dependent on careful consideration of cultural management f include site selection, site preparation, seed selection and handling, shading actors which and mulching, pest and nutritional management, and handling of harvested crops. Diseases of particular concern in Atlantic Canada are root rots caused by Phytopkthora cactorum, Cylindrocarpon destructans and Fusarium sp. Recently two systemic fungicides (metalaxyl and fosetylal) were registered; however, growers in Atlantic Canada have experienced metalaxyl resistance resulting from the reliance on this single compound for the control of Phytophthora sap. Current research being conducted on alternative control of these diseases will be discussed. In weed control research, 2, 4-D, MCPA, clopyralid have continued to show promise for weed contro1 at low rates. In trials to evaluate non-selective herbicides as post-senescence or pre-emergence in ginseng, glyphosate (Round-up) provided control of perennials as well as willowherb and lambsquarters. In phytoxicity trials, ginseng significantly tolerated grass herbicides, including clethodim, rimsulfuron, trakloxydim, nicosulfuron and fenoxyprop. For broadleaf herbicides, significant tolerance was shown for bromoxynil, thifensulfuron methyl, flumetulam/clopyralid, thifensulfuro/tribenuron. Disease and weed management of ginseng in Atlantic Canada will be discussed.

• Korean Journal of Plant Resources
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• v.17 no.1
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• pp.24-27
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• 2004

‘Dongjanggun’ was developed at the Gyeongbuk Agricultural Research and Extension Services, Taegu in 2000. It was selected among the local varieties gathered korean native chinese chive from 1993 to 1996. It has longer and narrower leaves, stronger flavor than check variety ‘Greenbelt’. And also, contents of ascorbic acid in the leaves of ‘Dongjanggun’ was higher than the ‘Greenbelt’s. Number of tillers per plant was greater in ‘Dongjanggun’ than that in ‘Greenbelt’ during the winter in unheated plastic house. Its growth and regrowing velocity after cutting of top leaves were vigorous. Number of flowers and seeds per umbel were fewer in ‘Dongjanggun’ than in ‘Greenbelt’. Average yield was 6% higher than ‘Greenbelt’s during the thee years.

• Research in Plant Disease
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• v.14 no.1
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• pp.26-31
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• 2008

Anthracnose caused by Colletotrichum spp. has been known as a significant disease which commonly infects to the fruits of Chinese matrimony (Lycium chinese) in the field conditions. To select effective fungicides for the control of Chinese matrimony anthracnose, the antifungal activity of 15 fungicides were evaluated with 13 different strains of Colletotrichum spp. in the laboratory condition. Six fungicides (Dithianon WG, Tebuconazole SC, Tebuconazole WG, Trifloxystrobin + Tebuconazole SC, Azoxystrobin SC and Polyoxin D zinc salt + Carbendazim WP) out of them, showed effective suppression with the mycelium growth of pathogenic fungus, and were selected to test in vivo of the field condition. Five fungicides, Dithianon WG, Tebuconazole WG, Trifloxystrobin + Tebuconazole SC, Tebuconazole SC and Azoxystrobin SC, were significantly effective to protect anthracnose of Chinese matrimony, the variety "Chungyang Jerae".

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.212-226
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• 2002

North American ginseng production may have been maximized in the traditional growing areas in the last decade and further increases may be in woods grown root, for niche markets. The marketplace demands high quality roots. Most problems leading to low quality roots start with the grower and can be avoided. These include poor site selection, inadequate soil drainage, untimely and poorly applied pesticides, and neglect of good sanitary practices. Selection of low lying sites increased the plant damage from frost in Ontario in May 2002. Seeding is still the major method of propagation of ginseng in spite of some success in culturing different parts of the plant. Opportunities exist for shortening the stratification period of North American ginseng seed to allow spring planting. This may reduce disease incidence. Since only one-third of ginseng seed sown ultimately produces plants harvested after 3 years any approach that reduces disease incidence and improves seed germination, seedling emergence and crop stand must be pursued. Disease is the major problem in ginseng cutivation from seed stratification, soil preparation prior to planting, right through to drying of the roots. Replant disease remains as an unresolved problem and needs full characterization and new approaches for control. Much progress has been made in research and related extension activities in disease control although challenges will arise such as with Quintozene and its replacement with Quadris for control of diseases caused by Rhizoctonia. Decreased labor populations and increased associated costs for ginseng production are causing rapid mechanization in every aspect of the ginseng industry. Engineers, machinery dealers, and fabricators, and growers are being challenged to increase efficiency by mechanization.

• BMB Reports
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• v.49 no.3
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• pp.149-158
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• 2016

Plants have evolved a vast chemical cornucopia to support their sessile lifestyles. Man has exploited this natural resource since Neolithic times and currently plant-derived chemicals are exploited for a myriad of applications. However, plant sources of most high-value natural products (NPs) are not domesticated and therefore their production cannot be undertaken on an agricultural scale. Further, these plant species are often slow growing, their populations limiting, the concentration of the target molecule highly variable and routinely present at extremely low concentrations. Plant cell and organ culture constitutes a sustainable, controllable and environmentally friendly tool for the industrial production of plant NPs. Further, advances in cell line selection, biotransformation, product secretion, cell permeabilisation, extraction and scale-up, among others, are driving increases in plant NP yields. However, there remain significant obstacles to the commercial synthesis of high-value chemicals from these sources. The relatively recent isolation, culturing and characterisation of cambial meristematic cells (CMCs), provides an emerging platform to circumvent many of these potential difficulties.

• Journal of Ginseng Research
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• v.42 no.2
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• pp.158-164
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• 2018

Background: The study was carried out to assess the genetic variability present in ashwagandha and to examine the nature of associations of various traits to the root yield of the plant. Methods: Fifty-three diverse genetic stocks of ashwagandha (Withania somnifera) were evaluated for 14 quantitative characteristics. Analysis of variance, correlation, and path coefficient analysis were performed using the mean data of 2 years. Results: Analysis of variance revealed that the genotypes differed significantly for all characteristics studied. High heritability in conjunction with high genetic advance was observed for fresh root weight, 12 deoxywithastramonolide in roots, and plant height, which indicated that selection could be effective for these traits. Dry root weight has a tight linkage with plant height and fresh root weight. Further, in path coefficient analysis, fresh root weight, total alkaloid (%) in leaves, and 12 deoxywithastramonolide (%) in roots had the highest positive direct effect on dry root weight. Conclusion: Therefore, these characteristics can be exploited to improve dry root weight in ashwagandha genotypes and there is also scope for the selection of promising and specific chemotypes (based on the alkaloid content) from the present germplasm.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.335-339
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• 2003

Several experiments were carried out to transfer LEAFY gene to Dendranthema grandiflora 'Shuho-no-chikara' by Agrobacterium LBA4404 carrying pSK109 encoding LEAFY gene. Kanamycin 10mg/L was used in first selection medium, and 20mg/L in the second one. Co-culture for 3 days was more effective in increasing transformation efficiency than that for 7 days. The transformation efficiency by Agrobacterium LBA4404 carrying pSK109 encoding LEAFY gene was about 2.8％ until the second selection, but only 0.13％ of shoots (two plants) was confirmed as a transgenic plants in Southern analysis. The escape of putative transformants was occured seriously in the process of selections, PCR analysis for confirming of neomycin phosphotransferaseII (npt II), and Southern analysis for LEAFY gene. One transgenic plant appeared 7 days'early flowering in field.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.12
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• pp.55-60
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• 2015

PG and RG methods are widely known method for calculating the capacity of the emergency generator in construction electrical installation. PG and RG methods are mainly used as a saving a life, fire protection, fire fighting in construction. Because no long distance between the emergency generator and electric motor feeder, the relatively small motor power in construction electrical installation, the capacity of generator in PG and RG methods are little problem of voltage and reactive power of generator. However in many cases the application of the PG and RG method is difficult in the Chemical Plant because it is long distance between the generator and the motor Feeder and motor capacity is very large. Motor starting power factor is about 0.2 lagging power factor and motor starting current is about 6times during motor staring. Also Most of the staring current component is a reactive power component. therefore, it is many cases that lack of reactive power and excess of allowable voltage drop limit and After selection of emergency diesel generator, problems happen during motor starting. Therefore, to be selection of effective emergency generator, active generator power, reactive power and the required reactive power during large motor starting should be considered in chemical plant. It is also required of the verification process through simulation because hand calculation is very difficult considering study cases.