• Bulletin of the Korean Mathematical Society
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• v.56 no.2
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• pp.333-349
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• 2019

We give explicitly an average value formula under the multiplication-by-2 map for the x-coordinates of the 2-division points D on the Jacobian variety J(C) of a hyperelliptic curve C with genus g if $2D{\equiv}2P-2{\infty}$ (mod Pic(C)) for $P=(x_P,y_P){\in}C$ with $y_P{\neq}0$. Moreover, if g = 2, we give a more explicit formula for D such that $2D{\equiv}P-{\infty}$ (mod Pic(C)).

• Korean Journal of Plant Taxonomy
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• v.50 no.4
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• pp.413-418
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• 2020

A new variety, Lecanorchis japonica var. insularis (Orchidaceae: Vanilloideae), a mycoheterotrophic orchid from Jejudo Island, Korea, is described and illustrated. It usually grows with L. japonica var. japonica, L. japonica var. hokurikuensis and L. kiusiana in evergreen forests. The newly described variety is distinguished from L. japonica vars. japonica, hokurikuensis, and kiiensis by having fully opened, larger flowers and an obtuse labellum apex.

• Korean Journal of Plant Taxonomy
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• v.40 no.4
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• pp.262-266
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• 2010

A new variety of Elsholtzia splendens (Lamiaceae) was found by the roadside of a mountain base at Jungmun-dong, Seogwipo-si, Jeju-do. The new taxon is termed Elsholtzia splendens var. fasciflora N.S. Lee, M.S. Chung & C.S. Lee, var. nov. The Korean name 'Da-bal-kkot-hyang-yu' was given. The morphological characters and illustrations of the species based on the holotype are provided together with a photograph of the habitat. It is distinctly distinguished from Elsholtzia splendens var. splendens by a few characteristics: leaves that area 2-4 cm long, leaves beneath the inflorescence, typically mostly 4; and inflorescence mosyly 2-4, fascicled, involucres oval.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.320-327
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• 2023

Capsicum annuum belongs to the Solanaceae family, crops of which are extensively cultivated worldwide. It is a food source containing various nutrients and vitamins and also serves as a medicine for treating ailments. The burning feeling experienced while consuming Capsicum fruits is due to the presence of capsaicinoids, particularly capsaicin and dihydrocapsaicin. This study aimed to assess the content of these two compounds in 34 varieties of capsicum and paprika. High-performance liquid chromatography with a gradient elution system and a reverse-phase YMC Pack-Pro column with UV detection at 280 nm was employed. The results revealed that, among the 34 samples, only six samples (samples 1, 15, 20, 29, 32, and 34) contained capsaicin and dihydrocapsaicin, and their highest contents were found in sample 1 - variety name: Sungil-c (capsaicin: 3.42 mg/g extract, dihydrocapsaicin: 1.20 mg/g extract). These findings suggest that the content of these two compounds is attributed to the variety and is influenced by geographical location and environmental factors. Additionally, this study provides a basis for establishing a C. annuum variety with high capsaicin and dihydrocapsaicin contents.

• YAKHAK HOEJI
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• v.12 no.1_2
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• pp.32-34
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• 1968

Aconitum Uchiyamai NAKAI "geu-neul-dol-che-gi"(Ranunculaceae), is geographically distributed only in Korea. An aconite collected at Mt. Dukwoo, Kangwon-Do flowers with white color in October. The aconite is different from Aconitum Uchiyamai NAKAI from the point of anatomical and morphological views in transplanted and collected aconites. Being a new variety of Aconitum Uchiyamai NAKAI, this aconite is anounced under the name of Aconitum Uchiyamai NAKAI var. albiflorum CHUNG et RIM, "Hin-geu-neul-dol-che-gi" called in Korea. Aconitum Uchiyamai NAKAI var. albiflorum CHUNG et RIM Differt a planta Aconitum Uchiyamai NAKAI per colorem album.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.179-184
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• 1976

Properties of starch from three rice varieties in Korea, Indica types Tongil, Yusin and a Japonica type Jinheung were investigated. 1) Gelatinization temperatures of Tongil, Yushin and Jinheung rice were $72^{\circ}C,\;70^{\circ}C\;and\;68{\sim}69^{\circ}C$ respectively. Gelatinization temperature of Indica variety was higher than that of Japonica variety. 2) Blue values of Tongil, Yusin and Jinheung rice starch were 0.40, 0.39 and 0.35 respectively, in which differences among rice varieties were small. 3) Color intensity of three varieties of rice starch with iodine gave rise to absorption maxima at $610{\sim}625\;nm$. 4) Amylose contents of Tongil, Yusin and Jinheung rice starch were 23.2%, 21.3% and 20.6% respectively, which were lower than those of other cereals. Amylose content of Indica variety was higher than that of Japonica variety. 5) Alkali numbers of Tongil, Yusin and Jinheung rice starchs were 7.0, 7.0 and 6.8, respectively. The differences were negligible among rice varieties. Those values were higher than that of glutinous rice starch.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1632-1636
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• 2003

Palladium-catalyzed cross-coupling reactions of neopentyloxysulfonylphenyl bromides with arylboronic acids provided a variety of neopentyl biphenylsulfonates in good yields. 2-Bromo- and 4-bromobenzenesulfonates underwent the coupling reaction more rapidly than 3-bromobenzenesulfonate, while chlorobenzenesulfonate did not produce the coupling product under the standard reaction conditions.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.108-108
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• 2017

The objective of this study was to know prospect and present state of new variety breeding of Forage and Grassland in South Korea. The industry of forage in Korea is going up to expend through utilization of good quality forage, Italian ryegrass, forage corn and oat rather than rice straw. Especially, since 2007, Italian ryegrass(IRG) had been very important major winter forage crop in South Korea and developed 13 varieties including very early maturity variety (three varieties), early maturity variety (three varieties), medium maturity variety (one variety) and late maturity variety (six varieties). But the disadvantage of Italian ryegrass was weak winter hardness and drought but has good advantage of forage nutritive value, high-yielding and high sugar content, and like livestock as like hanwoo, dairy cattle, goat so on. The Ko-variety (Korea developed variety) of Italian ryegrass has high cold-tolerant and adaptability more than any other country developed variety, and expend to cultivation area from southern area (below Daejeon) to middle-northern area (upper Han river). Although the cultivation area of Italian ryegrass of South Korea was 21,700 ha in 2007, right now, that of Italian ryegrass is about 123,600ha due to expend cultivation area and know famer to good forage crop and have a various maturity varieties (very early, early, medium, late) according to local situation (before-crop harvesting stage or double cropping system). The seed market of Italian ryegrass in South Korea becoming extended to around 100 million Korean won and seed export get nearer to foreign country. We are going to develop of new variety for stress tolerant and high yield and quality forage variety, good adaptability to the Korean environmental conditions including reclaimed area, make self-sufficiency system for forage seed (Italian ryegrass), export our seed to foreign countries.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.588-590
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• 1994

This paper describes current controlled PWM technique of IPM synchronous motors for a wide variety of speed control applications. The IPM synchronous motors have a saliency, in which the q-axis inductance is larger than the d-axis inductance. As a consequence, there exists a reluctance torque component Thus when this component is added to the torque component produced by the stator currents and the air-gap flux, IPM motor drives are readily applicable where full torque Is required up to full or base speed. They are however limited in their ability to operate in the power limited regime where the available torque is reduced as the speed is increased above its base value. This paper reviews the operation of the IPMSM drives when they are constrained to be within the permissible envelope of maximum inverter voltage and current to produce the rated power and to provide this with the highest attainable rotor speed. The wide variety of speed control strategy is analyzed and the performance is investigated by the computer simulation using actual parameters of a drive system. Simulation results are given and discussed.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.305-310
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• 2023

Bandiburichodang (BDC) is a new variety of Zea mays L. Total polyphenol content (TPC) assay and quantitative analysis of ferulic acid (FA) were performed to determine the steaming, roasting conditions of BDC kernels that lead to the highest content. TPC levels increased after roasting under all conditions. TPC levels in samples steamed at 115 ℃ for 25 min were 3.157 mg/g before roasted, and increased to 3.825 and 4.739 mg/g after roasting at 160 and 200 ℃, respectively. Whether BDC kernels were roasted was relevant with TPC content. BDC kernels were extracted to perform quantitative analysis of FA. Roasting temperature affected FA content: the higher the temperature, the lower the content. BDC kernels that were steamed at 115 ℃ for 25 min had 0.178 mg/g of FA content before roasting, and levels decreased to 0.132 and 0.115 mg/g after roasting. Under different roasting conditions, FA content decreased 15 to 50%. We hypothesize that this phenomenon is due to a breakdown of phenolic compounds or cell wall disruption.