• Korean Journal of Plant Taxonomy
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• v.45 no.3
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• pp.266-271
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• 2015

Elaeagnus pungens Thunb., belongs to the family Elaeagnaceae, was recently recorded for the first time in Mt. Miruk, Tongyeong-si, Gyeongsangnam-do. The native distribution range of this species includes China and Japan in East Asia, while it is considered as an invasive species in North America. Elaeagnus pungens is related to E. glabra, but the species can be distinguished from its congeners by having revolute and repand leaf blades, silvery white and brown scales on the abaxial surface of the leaf, and a campanulate calyx. We propose the new Korean name 'Tong-yeong-bol-re-na-mu,' based on its first collecting site. A detailed description of vegetative and floral characteristics, trichome scanning electron micrographs, dichotomous keys, and the habitat of this species are also provided.

• Korean Journal of Plant Taxonomy
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• v.41 no.1
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• pp.51-57
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• 2011

The microstructure of the leaf epidermis and trichomes of Fallopia sect. Reynoutria are examined using scanning electron microscopy. Fallopia sachalinensis was distinguished from other taxa in this section by its prominent epicuticular wax layer consisting of protruding wax rodlets. In addition, epicuticular rodlets of F. sachalinensis individuals from Ullung Island and Dok Island appear to be thinner than those from other regions, including Japan and Sakhalin. The stomatal size appears to be related to the ploidy level in the sect. Reynoutria, as the hexaploids, octoploids and dodecaploids tend to have larger stomata as compared to tetraploids. Three basic types of trichomes were found in the section; (1) conical unicellular trichomes, (2) uniseriate filiform trichome consisting of 1-8 cells, and (3) peltate glandular trichomes. The trichome types and their distribution appear to be useful in distinguishing the taxa in the section.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.4
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• pp.498-505
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• 1999

The ferrite device that has nonreciprocal characteristics has been used as various microwave components. In this paper, the spectral-domain method was used to analyze the characteristics of structure(strip line on multilayer structure with ferrite material) for which no paper has been published yet. It is assumed that an external dc magnetic field is applied perpendicular to the ground conductor. The propagation constant is calculated for each parameter and frequency. Also we considered convergence by increasing the number of basis functions and verified the numerical analysis results. From the results, we could confirm that as the thicknesses of YIG is increased, the cutoff region is widened and the propagation constant is decreased at the frequency of upper cutoff region. For a larger applied dc magnetic field, the frequency of cutoff region is found to be increased. Also the simulation results for strip line show that the cutoff region is widened and the propagation constant is larger than that of microstrip line.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.1
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• pp.129-134
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• 2011

The construction method in electrical room with hydro power generation is well informed in drawings and according to this method, to master the actual working conditions. It's necessary to consult location of KEPCO liability threshold with the KEPCO side, therefore make a decision to install the underground cable in hydro power station in each state, including outdoor pipes and manholes. Undulating rigid polyethylene conduit (125C) and CNCV-W extra high cable are laid and installed, to make a closely analysis to the construction by reviewing its process. In this work, the key part of the KEPCO power system for House of Commons is actually based on liability threshold, even including outdoors pipeline construction, high voltage underground electrical wiring and switchgear installation. It directly reveals the contents of the proposed construction methods about Housing Corporation and the High Voltage Switchgear Installation Inlet.

• Korean Journal of Plant Taxonomy
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• v.32 no.4
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• pp.397-416
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• 2002

A taxonomic study of Viola section Chamaemelanium in Korea, based on morphological characters, was conducted with light microscopy and scanning electron microscopy. Two species, V. orientalis W. Becker and V. brevistipulata (Fr. et Sav.) W. Becker, are recognized by rhizome and cauline habits, trichomes on the ovary and the shape and beards of stigmas. The latter can be split further into three varieties, var. brevistipulata, var. minor Nakai and var. laciniata (Boiss.) W. Becker, according to the leaf morphology in particular. Viola brevistipulata var. laciniata has the most tooth number, and its teeth are irregular erose but the other two varieties are regular sinuate or serrate. As for the size of leaves, V. brevistipular var. brevistipulata is the largest but V. brevistipulata var. minor is the smallest among the varities. Of them, V. brevistipulata var. laciniata is newly recorded in Korea. It was also revealed that both development and arrangement of the beards developed on the ovary and stigma were particularly diagnostic in the identification of the Viola section Chamaemelanium species.

• Journal of Korean Society of Forest Science
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• v.82 no.3
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• pp.260-270
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• 1993

This study was carried out to clarifyed a taxonomical relationships of Rutaceae on the subfamily, genus and species level in Korea using venation pattern and stomata types. The results are summarized as follows : The leaf venation of the Rutaceae has revealed three major venation types. Semicraspedodromous, Brochidodromous and Cladodromous. The leaf ufmations type of the genus Evodia and Phellodendron were similar to Cladodromous type. They showed gradual evolution from brochidodromous type of Aurantioideae to cladodromous type of Toddaloideae. The stomata ypes were reconized Anomocytic and Actinocytic type, and epidermal cells were Ansio. Polygonal and Medium type. In the correlation analysis, there were highly significant correlation between frequency and length (r=-0.822), frequency and width (r=-0.780), and length and width(r=0.909) at 1% level.

• Journal of the Korean Association of Geographic Information Studies
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• v.3 no.1
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• pp.35-43
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• 2000

The slope gradient of the Korean Peninsula was analyzed by using DEM(DTED level 1). The Peninsula has high percentages of gentle slopes. But low plains and very steep slope regions are scarcely distributed in the Peninsula. Altitude lower than 150m areas are composed of plains and undulated plains. The steepest and most rugged topographies are observed in the range of altitude from 500m to 1,000m areas. The areas of altitude greater than 1,000m show plateau landscapes. By overlapping digital geology maps and the gradient grade maps, We revealed the characteristics of slope regions by geological districts. High latitude with steep slope are well developed in the geological districts of granitic gneiss(ARgr) and gneiss($PR_1$) of the Pre-Cambrian, sandstone of the Paleozoic era(P-T), and sedimentary rocks of the Mesozoic era($J_2$). Low altitude with gentle slope areas are representative in the districts of granite of the Mesozoic era($Jgr_1$), the Cretaceous sedimentary rocks of the Mesozoic era($K_1$, $K_2$) and the Cenozoic strata(N). Basalt extruded the Quaternary($Q_1$) are observed in the areas of very gentle slope but greater than 1,000m altitude.

• The Journal of the Acoustical Society of Korea
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• v.19 no.5
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• pp.79-83
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• 2000

When passband ripple α/sub p/ and stopband attenuation α/sub s/ at the w/sub s/ where the stopband begins are specified in filter design, △α/sub s/ usually exceeds the specification by △α/sub s/ due to the necessity that the order n of the filter function be an integer. In this paper, we apply a trade-off method to remove the excess stopband attenuation △α/sub s/ for reducing the value of pole-Q and improving the characteristics of the Chebyshev filter function. We also apply the trade-off method of pole-Q reduction to the modified Chebyshev function, and then the 4 types of function have been analyzed to compare in frequency and time domain characteristics. The trade-off method reduces the pole-Q which influences the filter characteristics to maximum 49.6% without increase of the order n. Thus implies that they have the improved characteristics such as the reduced passband ripple and flatter delay characteristics as compared Chebyshev filter function before trade-off. And the unit step response shows shorter delay time and settling time in time domain performance.

• The Korean Journal of Mycology
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• v.21 no.2
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• pp.120-126
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• 1993

Morphological characteristics in the anamorphic states were described in three species of powdery mildew fungi, Microsphaera akebiae, M. picrasmae and M. schizandrae, which were parasitic on Akebia quinata, Picrasma quassioides, and Schizandra chinensis, respectively. All species were flexuous in foot-cells of conidiophores, producing conidia singly on conidiophores, devoid of fibrosin bodies in conidia, and producing germ tubes on the end of conidia.

• Korean Journal of Medicinal Crop Science
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• v.6 no.3
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• pp.216-220
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• 1998

The objectives of this study were to evaluate the effects of some seed pretreatments on seed germination, emergence, growth and yield of Bupleurum falcatum L. Seed treatments included stratification in open-field during winter, washing with running water, low temperature storage, soaking into $H_2SO_4$ solution, and scarification. Germination increased 15% by stratification and 9% by washing treatment compared to non-treatment, control. It was suggested that washing treatment leached inhibiting substance, while stratification treatment leached inhibiting substance and promoted growth of immatured embryo. In the field mulched with rice straw, stratification and washing treatments were effective to shorten days to emergence by 31 and 21 days and to increase emergence rate by 7 and 5 %, respectively, compared with control. By these two treatments, root growth was improved, the number of harvested plants was increased considerably and dry root yield per ha were increased by 29 and 22 %, respectively, compared with control.