• Journal of the Korean Mathematical Society
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• v.44 no.1
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• pp.211-235
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• 2007

In this paper, first we introduce the full expression of the curvature tensor of a real hypersurface M in complex two-plane Grass-mannians $G_2(\mathbb{C}^{m+2})$ from the equation of Gauss and derive a new formula for the Ricci tensor of M in $G_2(\mathbb{C}^{m+2})$. Next we prove that there do not exist any Hopf real hypersurfaces in complex two-plane Grassmannians $G_2(\mathbb{C}^{m+2})$ with parallel and commuting Ricci tensor. Finally we show that there do not exist any Einstein Hopf hypersurfaces in $G_2(\mathbb{C}^{m+2})$.

• Mycobiology
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• v.32 no.2
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• pp.98-101
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• 2004

A fruit soft rot caused by Mucor piriformis occurred on sweet persimmon storages in Jinju, Changwon and Gimhae, Gyeongnam province, Korea, 2003. The disease infection usually started from wounding after cracking of fruits. At first, the lesions started with water soaked and rapidly softened and diseased lesion gradually expanded. Colonies on potato dextrose agar at $20^{\circ}C$ were whitish to olivaceous-buff Sporangia were globose, black and $96{\sim}153{\mu}m$ in size. Sporangiophores were $26{\sim}42{\mu}m$ in width. Sporangiospores were ellipsoid and $5.8{\sim}10.6{\times}4.3{\sim}7.6{\mu}m$ in size. Columella was obovoid, cylindrical-ellipsoidal, pyriform, subglobose and $80{\sim}125{\mu}m$ in size. Optimal temperature for mycelial growth was $20^{\circ}C$ on PDA. The causal organism was identified as M. piriformis. This is the first report of fruit soft rot on sweet persimmon caused by M. piriformis in Korea.

• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.31-39
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• 1996

Many higher fungi were collected at MI.Moak Provincial Park (Chonlabuk-Do), Mt.Pangtae(Kangwon-Do) and Byunsan Pennisula National Park from April. 1995 to October, 1995. These higher fungi were identified.According to the results, these species were newly to Korea: Laccaria ohiellsis, Mycef1a clavularis. M.acicula. Marasmius ramealis. M.calopus, Strobilurus esculefltus, Agrocybe sphaleromorpha and Corlinarius fasciatus.

• Journal of Astronomy and Space Sciences
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• v.34 no.1
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• pp.37-44
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• 2017

In this paper, analysis results of the photometric data of DO Dra will be presented. DO Dra had been observed with 1 m LOAO telescope and 0.6 m CBNUO telescope from 2005 through 2014. The data shows kind of periodic oscillation behavior in the orbital period and also in the spin period. It has been found that these QPOs are not observed always and that the periods vary from 30 min to 80 min. We also found that the period variation seems to repeat itself with the period of 13.5 days. It is essential to monitor this object in the future as well as to carry out model calculation in order to have better understanding of these QPO phenomena.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.683-686
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• 2002

To achieve optimum operation of a thermophilic aerobic digestion (TAD) process for waste activated sludge (WAS), TAD experiments using Bacillus stearothermophilus (ATCC 31197) were carried out to investigate the optimum concentration of dissolved oxygen (DO). TAD reactors were operated at DO concentrations of 0, 1, 2, 3, 4, and 5 ppm, and the results showed that the WAS could be successfully degraded by a TAD system operated with a DO concentration of 1 ppm and above. When the TAD system with an optimum additive (2 mM Ca ion), selected from a previous study, and 1 ppm DO concentration were combined with a thermal pretreatment ($121^{\circ}C$, 10 min), the results exhibited upgraded total suspended solids and an enhanced protein degradation.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.235.2-235.2
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• 2010

In this study, the wave power resources at the southern sea of Korea were estimated by using the hindcasted wave data of previous researches. The used data were wave heights, periods and directions which were hindcasted around the Korea peninsular from 1979 to 2003. The spatial resolution of the hindcasted data is $1/6^{\circ}$(about 18 km). In winter, the northwest monsoon increase the wave power, while the wave power around Korea peninsular is very small in spring. The maximum value of the annual mean wave power is about 13 kW/m at Gageo-do, Heuksan-do and western region of Jeju-do, while those at the southern sea of Korea is only 4 kW/m, which is relatively small. The wave power at Korean east sea is lower than that of Korean southern sea. We obtained the wave resources information, in a fine grid, at Gageo-do, Heuksan-do, and western sea of Jeju-do, by solving SWAN model with the boundary conditions of hindcasted wave data.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.223.2-223.2
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• 2003

A rapid, sensitive and selective liquid chromatography-tandem mass spectrometric (LC/MS/MS) method for the determination of eupatilin in human plasma was developed. Eupatilin and internal standard, (S)-[N-3-(4-(2-(1-methyl-5-tetrazolyl)-pyridine-5-y1)- 3-fluorophenyl)-2-oxo-5-oxazolidinyl]methyl acetamide (DA-7867) were extracted from human plasma by liquid-liquid extraction and analyzed on a phenyl-hexyl column with the mobile phase of acetonitrile-ammonium formate (10 mM, pH 3.0) (60:40, v/v). (omitted)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.130-136
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• 2006

Growth and quality of rice are affected by various factors including the location of cultivation. This study was conducted to investigate the effects of altitudinal locations on the growth and yield-related components of rice. Nineteen Japonica type varieties were grown at Iksan (altitude, 10 m), Imsil (altitude, 150 m), Jinan (altitude, 275 m) and Jangsu (altitude, 430 m) at a similar latitude in Jeonbuk province in the south western Korea. Minimum air temperature showed a strong negative correlation with altitude. The morphological traits and yield-and quality-related components were analyzed. Longer days to heading was required at higher altitudes. However, culm length, panicle length, panicle number, grain number and rice yield were reduced at higher altitudes. Protein content of brown rice increased but fatty acid content decreased at higher altitudes. Amylose content was affected by neither the altitude nor the ecotype. Palatability of polished rice tends to be improved at higher altitudes and in early-maturing ecotypes but its relationships with altitude and ecotype were not significant. Head rice ratio was lower at higher altitudes but broken rice ratio vise versa. These results indicate that growth and quality of rice are affected significantly by changes in temperatures at the locations of different altitude. Also, the characters related to yield and quality of rice often respond incompatibly to the changes in altitudes. These results could provide valuable information for the strategic planning of rice production in geographically diverse areas.

• Food Science and Preservation
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• v.11 no.4
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• pp.503-507
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• 2004

The quality of bread made of sprouted brown rice ($20\%$), wheat flour and pumpkin powder was investigated. The bread was manufactured with 0, 1, 3 and $5\%$ pumpkin powder (W/W) with increasing and wheat flour. Volume of the breads were decreased from 4.68 mL/g to 3.60 mL/g as pumpkin powder contents increased from $0\%\;to\;5\%$. Lightness decreased with increasing pumpkin powder contents. Yellowness increased from 10.97 to 27.01 with increasing pumpkin powder contents. Textural characteristics of bread crumb were influenced by adding additives pumpkin powder. Hardness, adhesiveness and chewiness of bread decreased as the added level of pumpkin powder. In sensory evaluation, sensory scores for color, flavor and overall quality of bread increased with increasing pumpkin powder contents.

• Journal of Mushroom
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• v.19 no.3
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• pp.246-250
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• 2021

The main characteristics of a new cultivar 'Jinhyang', a cross of a collection of monokaryotic strains of the brown button mushroom, were examined. 'Jinhyang' was not significantly different from the control cultivar 'Dahyang' in mycelial culture and cultivation period. The cap of 'Jinhyang' was thicker and darker in color than that of 'Dahyang'. The hardness and individual weight of the fruiting body of 'Jinhyang' were slightly higher than those of 'Dahyang'; however, the differences were not significant. The yield of 'Jinhyang' was 14.1 kg/m², which was 8% higher than that of 'Dahyang'. Therefore, it is expected that it will be possible to supply this cultivar growers in the future.