• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.1
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• pp.87-94
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• 2010

This study mainly focused on the subsurface settlement due to shallow and deep tunneling in sandy ground. In order to figure out theoretical deformation patterns in association with the ground loss during the progress of tunneling, laboratory model tests using aluminum rods and finite element analyses using the CRISP program were carried out. As a result of comparison between the model test and the finite element analysis, the similar deformation patterns were found. In addition, it was identified that the most K values obtained from both the FEA and the model tests were distributed between Dyer et al. (1996) and Moh et al. (1996) of the field observation data. Based on the model test data, the linear equation of K for the sandy soil could be obtained.

• Honam Mathematical Journal
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• v.32 no.1
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• pp.177-192
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• 2010

We study the concepts of congruent number problems and elliptic curves. We research the structure of the group of elliptic curves and find out a method of the computation of L($E_n$, 1) and L'($E_n$, 1) by using SAGE program. In this paper, we obtain the first few congruent numbers for n ${\leq}$ 2500.

• Journal of the Korean Mathematical Society
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• v.45 no.3
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• pp.699-709
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• 2008

We study homology of the gauge group associated with the principal $G_2$ bundle over the four-sphere using the Eilenberg-Moore spectral sequence and the Serre spectral sequence with the aid of homology and cohomology operations.

• Journal of the Korean Mathematical Society
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• v.35 no.1
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• pp.149-164
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• 1998

We study the homology of the tripe loop space of the exceptional Lie group $F_4$ by exploiting the spectral sequences and the homology operators.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.53-61
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• 1986

The races of soybean cyst nematode, Heterodera glycines were investigated at 13 localities in Kyungpook, Chungpook and Cheonnam provinces for the resistant soybean variety selection to soybean cyst nematode. Race C, 1, and 5 were distributed and among them race 5 was dominant in Korea. Native soybean 203 lines and 25 introduced soybean varieties were investigated in field where soybean cyst nematode race 5 infested. As the result, the reproduction of soybean cyst nematode in native soybean lines decreased on entry number 18, 21, 36, 38, 41, 42, 43, 45, 55, 59, 68, 72, 75, 93, 94, 95, 98, 123, 131, 136, 146, 170, 174, 187, 190, 191 than others. And then, in pot experiment, entry number 170 showed moderately resistant with 10 cysts per root, while entry number 55 was decreased reproduction a little and the other 25 line appeared susceptibility. In introduced soybean varieties, Peking, Illsoy and PI90763 showed resistance and not reproduction in field and pot experiment. But Custer, Delmar, Dyer and Jackson represented moderately resistant under 10 cysts, while the other 18 varieties were susceptible. In yield analysis, native soybean line 170 showed the same tendency as Peking and PI90763 known for resistant varieties in decreased rate of branch number, pod number, pod weight per plant and weight of 100 grains. Peking and PI90763 decreased at the rate of under 1.6% in branch number, pod number, pod weight per plant and weight of 100 grains, while Illsoy showed a little higher decreased rate of 3.8% in pod number and 3.4% in pod weight per plant. Custer, Delmar, Dyer and Jackson represented a little higher decreased rate in yield.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.246-248
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• 2011

Triadenum breviflorum (Wallich ex Dyer) Y. Kimura in Nakai & Honda (Hypericaceae), previously known only in northeast India, China and Taiwan, was found in a few wetlands of Jeju Island in 2008. Additionally, some images online of T. breviflorum suggest that it exists in other places on the Korean peninsula but that it has been misidentified as Triadenum japonicum. This species is distinguished from the latter by white petals, inflorescence from nodes 6-11, linear to narrowly elliptic leaves, and an attenuated base. The local name Huin-kkot-mul-go-chu-na-mul implies a white flower rather than the flesh-pink color of T. japonicum. The morphological characteristics of the species are provided with photographs of the habitat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1191-1200
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• 1999

This study was designed to determine total lipid and trans fatty acids(tFAs) content of 157 food items commonly consumed in the Korean diet and to prepare the database for the estimation of tFAs intake in Koreans. Total lipid and tFAs content was determined by Bligh and Dyer method and attenuated total reflection infrared spectroscopy, respectively. The content of tFAs in margarines ranged from 0.8% to 25.2%, depending on the manufacturers. In bakery products, cakes contained higher levels of tFAs(0.8~16.9%) than hamburgers(0.8~8.4%) and doughnuts(4.9~10%). The distribution of tFAs in crackers and cookies was wide(0.8~25%), whereas meat and fish products contained 0% to 8.9% of tFAs. Fried chickens had 0% to 14.6% of tFAs and French fries had 5.2% to 18.8% of tFAs. In noodles, nuts, chocolates and fermented fish sauces, tfAs were not detected.

• International Journal of Costume and Fashion
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• v.9 no.2
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• pp.79-96
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• 2009

The purpose of this study was to identify the impact of acculturation level and individualism/collectivism on shopping behaviors such as' informational influences, shopping orientations, and store patronage of Asian ethnic groups residing in the United States. A total of 129 Asian adults residing in North Carolina State of the U.S. completed questionnaires. Results showed statistically significant differences in responses to an informational influence (i.e., media source) and two shopping orientation subscales (i.e., shopping confusion in the Us. and personalized shopping) between low- and high-acculturated groups. A significant difference was found between the individualistic group and the collectivistic group on three shopping orientation subscales. Due to the potential importance of considering both acculturation and individualism/collectivism when looking at shopping behaviors, four groups were created by categorizing respondents on the basis of their acculturation level and individualism/collectivism scores. Comparison on shopping orientations and informational influences by four groups revealed statistically significant differences in response to two shopping orientation subscales and two patronage behavior subscales.

• Communications of the Korean Mathematical Society
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• v.21 no.2
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• pp.337-345
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• 2006

John Harer conjectured that the canonical map from braid group to mapping class group induces zero homology homomorphism. To prove the conjecture it suffices to show that this map preserves the first Araki-Kudo-Dyer-Lashof operation. To get information on this homology operation we need to investigate the image of braiding under the Harer map. The main result of this paper is to give both algebraic and geometric interpretations of the image of braiding under the Harer map. For this we need to calculate long chains of consecutive actions of Dehn twists on the fundamental group of surface.

• Korean Chemical Engineering Research
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• v.53 no.2
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• pp.205-210
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• 2015

In this paper, microalgae lipid extractions were performed using conventional organic solvent and supercritical carbon dioxide (SC-$CO_2$) for biodiesel-convertible lipid fractions. The highest levels (58.31%) of fatty acid methyl ester (FAME) content in the lipid extracted by SC-$CO_2$ was obtained, and 18.0 wt.% crude lipid yield was achieved for Bligh-Dyer method. In the SC-$CO_2$ extraction, methanol as a co-solvent was applied to increase the polarity of extract. The experimental results indicated that crude lipid yield, FAME content and yield extracted by combination of SC-$CO_2$ with methanol were 12.5 wt.%, 56.32% and 7.04 wt.%, respectively, and this method could reduce the extraction time from 2 hour to 30 min when compared to SC-$CO_2$ extraction. Therefore, SC-$CO_2$ extraction is proven to be an environmentally-friendly and an effective method for lipid extraction from microalgae.