• Journal of the Society of Naval Architects of Korea
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• v.51 no.5
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• pp.369-379
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• 2014

Planing hull forms have significant influences on those hydrodynamic performances in calm water and in waves. Therefore, the hydrodynamic performance of a planing vessel should be predicted by model tests or theoretical calculations, and be confirmed whether it shows the performance requirements at the design stage. In this study, four planing hull forms are designed with the goal of the improvement of resistance and seakeeping performance, and 1/6.5 scale model tests are carried out in Seoul National University towing tank. The effects of design parameters such as length-to-beam ratio, deadrise angle and forebody shape on the hydrodynamic performance are investigated, based on model test results. Running attitude and resistance of model ships in calm water are also estimated by empirical formulae proposed by Savitsky (1964; 2007; 2012), and compared with the model test results. It is shown that calm water performance of non-prismatic planing hulls can be predicted well by Savitsky (2012)'s formula which improves the original Savitsky(1964/2007)'s formula by taking into account the variations of deadrise angles, and the actual angles between the hull bottom and the free surface.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.5
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• pp.343-352
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• 2016

In this study, a pre-swirl duct for the 180,000 DWT bulk carrier has been designed from a propulsion standpoint using CFD. The stern duct - designed by NMRI - was selected as the initial duct. The objective function is to minimize the value of delivered power in model scale. Design variables of the duct include duct angle, diameter, chord length, and vertical and horizontal displacements from the center. Design variables of the stators are blade number, arrangement angle, chord length, and pitch angle. A parametric design was carried out with the objective function obtained using CFD. Reynolds averaged Navier-Stokes equations have been solved; and the Reynolds stress model applied for the turbulent closure. A double body model is used for the treatment of free-surface. MRF and sliding mesh models have been applied to simulate the actuating propeller. A self-propulsion point has been obtained from the results of towing and self-propelled computations, i.e., form factor obtained from towing computation and towing forces obtained from self-propelled computations of two propeller rotating speeds. The reduction rate of the delivered power of the improved stern duct is 2.9%, whereas that of the initial stern duct is 1.3%. The pre-swirl duct with one inner stator in upper starboard and three outer stators in portside has been designed. The delivered power due to the designed pre-swirl duct is reduced by 5.8%.

• Molecules and Cells
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• v.19 no.1
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• pp.104-113
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• 2005

Large inversions are well characterized in the chloroplast genomes of land plants. In contrast, reports of small inversions are rare and involve limited plant groups. In this study, we report the widespread occurrence of small inversions ranging from 5 to 50 bp in fully and partially sequenced chloroplast genomes of both monocots and dicots. We found that small inversions were much more common than large inversions. The small inversions were scattered over the chloroplast genome including the IR, SSC, and LSC regions. Several small inversions were uncovered in chloroplast genomes even though they shared the same overall gene order. The majority of these small inversions were located within 100 bp downstream of the 3' ends of genes. All had inverted repeat sequences, ranging from 11 to 24 bp, at their ends. Such small inversions form stem-loop hairpin structures that usually have the function of stabilizing the corresponding mRNA molecules. Intra-molecular recombination between the inverted sequences in the stem-forming regions are responsible for generating flip-flop orientations of the loops. The presence of two different orientations of the stem-loop in the trnL-F noncoding region of a single species of Jasminum elegans suggests that a short inversion can be generated within a short period of time. Small inversions of non-coding sequences may influence sequence alignment and character interpretation in phylogeny reconstructions, as shown in nine species of Jasminum. Many small inversions may have been generated by parallel or back mutation events during chloroplast genome evolution. Our data indicate that caution is needed when using chloroplast non-coding sequences for phylogenetic analysis.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.2
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• pp.147-157
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• 2011

A RANS(Reynolds averaged Navier-Stokes) based numerical method is developed for the evaluation of ship resistance and self-propulsion performances. In the usability aspect of CFD for the hull form design, the field grid around practical hull forms is generated by solving a grid Poisson equation based on the hull surface grid generated from station offsets and centerline profile. A body force technique is introduced to model the effects of the propeller in which the propeller loads are obtained from potential flow analysis using an unsteady lifting surface method. The free surface is captured by using a two-phase level-set method and the realizable $k-{\varepsilon}$ model is used for turbulence closure. The hull attitude in vertical plane, i.e., trim and sinkage, is calculated by using a quasi-steady method and then considered in the computation by translating and rotating the grid system according to the values. For the validation of the proposed method, the numerical results of resistance tests for KCS, KLNG, and KVLCC1 and of self-propulsion test for KCS are compared with experimental data.

• Food Science of Animal Resources
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• v.40 no.5
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• pp.772-784
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• 2020

This study was performed to investigate the effects of taste-related compounds and antioxidatve profiles of retorted samgyetang made from fresh and dried Cordyceps militaris (C. militaris) mushrooms. A total of 48 carcasses were prepared from commercial broilers (CB; Ross, 4 weeks old) and randomly distributed into eight different treatments. Each treatment group consisted of 6 chicken carcasses made with the addition of broth in different condition and concentration of C. militaris mushrooms. The addition concentration was based on the broth volume (v/w) under either fresh or dried conditions ranging from 0% as a control to 1%, 2%, and 3% of C. militaris mushrooms. C. militaris mushrooms contributed to an improvement of meat tenderness and the antioxidative profile that led to a greater suppression of lipid oxidation. The addition of C. militaris mushrooms at 2% could also enrich the flavor and taste-related compounds, particularly the increase in 5'-AMP and umami-related free amino acid compounds, L-aspartic acid and L-glutamic acid. Different addition forms of C. militaris mushrooms, particularly fresh or dried mushrooms, had only small effects on bioactive compounds, where the dried addition could possibly enrich samgyetang broth with higher cordycepin and adenosine contents than the fresh addition. Besides, the addition of C. militaris mushrooms in the dried form could also contribute to a higher antioxidative profile. Eventually, the addition of C. militaris mushrooms with a minimum addition of 2% contributed to an improvement of meat quality, antioxidative profile and flavor improvement of samgyetang.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.655-666
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• 2016

The purpose of this study was investigating effects of TBL (Team-based learning) on the academic achievements and learning satisfaction of university students. This study subjects were 46students in social welfare department. This study surveyed instructor-led classes and orientation of TBL, which is provided from the 1st week to 3rd week. Then, TBL was performed from 4th week to 14th week. The results were found by utilizing questionnaires and interviews through free form technology, which produced effective and measured responses. So academic achievements was improved significantly better than classical explanation teaching. And also learning satisfaction was improved with students' substantial amount, interesting and seamless interaction, active learning and participation, improved presentation technique, and competence in mutual communication. I suggest that TBL should be applied to other subjects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.1
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• pp.23-26
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• 2006

Effects of sera from several fish species and insulin on the development of cultured Silurus asotus hepatocytes were investigated. Hepatocytes with high viability (95%) were obtained from the livers of male catfish by two step collagenase perfusion. Isolated hepatocytes, initially showed a typical round-shape, firmly attached to the culture dish within 24 h. In the presence of catfish serum, hepatocytes attached each other, spread well on the dish and developed into monolayer after 3-4 days of incubation. Cells within the established monolayer became polygonal in shape and their nuclei and boundaries being clearly visible under the microscope. In contrast, when incubated in FBS-supplemented or serum-free medium, cells managed to form small clusters, each made of 2-10 cells. Cells in FBS-supplemented medium further developed into larger clusters. However, these clusters failed to develope into monolayer. In addition, when insulin was deprived from culture medium, formation of monolayer also failed. From these data, it can be concluded that the presence of both catfish serum and insulin is necessary for the formation of monolayer of catfish hepatocytes and the functional role of fish serum may differ from that of insulin and can not be displaced by FBS-supplementation.

• Journal of Plant Biotechnology
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• v.32 no.2
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• pp.135-138
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• 2005

Embryogenic callus was obtained from cotyledonary explants of Codonopsis lanceloata on Murashige & Skoog's medium supplemented with 1 mg/L 2,4-D. Suspension cultures of the embryogenic calli were grown on a shaker at 100 strokes/min, and then the calli were subcultured for 2 weeks in 2,4-D-free medium to produce somatic embryo. In somatic embryos at the globular stage, cotyledon initials began to differentiate themselves in the near distal end of the procambial strand. Dicotyledons, tricotyledon, tetracotyledon and fused cotyledon were differentiated from the distal ends of two, three, four and circular procambial strands, respectively. Nearly circular procambial strand in lower hypocotyls were independently differentiated into two, three, four procambial tissues at cotyledonary node and cotyledons to form somatic embryos with dicotyledon, tricotyledon, tetracotyledon. If the distal subepidermal cells of globular embryo exclusively became cotyledon initials, the torpedo or cotyledonary embryo was characterized by somatic embryos with fused cotyledon.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.10a
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• pp.17-17
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• 2010

Rhizobacteria are a diverse group of free-living soil bacteria that live in plant rhizosphere and colonized the root system. Plant growth-promoting rhizobacteria (PGPR) possessing ACC deaminase (ACCD) can reduce ACC and ethylene in plant tissue and mediated the growth of plants under various stresses including salt stress. ACCD decrease ethylene levels in plant tissue that produce high levels of ethylene in tissue via elevated levels of ACC under salt stress. We selected strains of Pseudomonas sp. possessing ACCD activity for their ability to promote plant growth under salt stress from soil sample collected at Byeonsan, Jeonbuk, South Korea. The Pseudomonas strains possessing ACCD increased the rate of the seedling and growth of chinese cabbage seeds under salt stress. We cloned ACCD gene from P.fluorescens and expressed recombinant protein in Escherichia coli. The active form of recombinant ACCD converted ACC to a-ketobutyrate. The in vivo treatment of recombinant ACCD itself increase the rate of the seedling and growth of Chinese cabbage seeds under salt stress. The polyclonal P.fluorescens anti-ACCD antibody specifically reacted with ACCD originated from Pseudomonas. This indicates that the antibody might act as an important indicator for ACCD driven from Pseudomonas exhibiting plant growth-promoting activity. This study will be useful for identification of newly isolated PGPR containing ACCD and exploioting the ACCD activity from PGPR against various biotic and abiotic stresses.

• The Research Journal of the Costume Culture
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• v.21 no.2
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• pp.151-166
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• 2013

This study aims to shed light on the diversity and complexity of design represented through modern fashion and to identify growth opportunities for globalizing and modernizing traditional clothing designs. To this end, formative trends and aesthetic characteristics of $21^{st}$ century fashion were analyzed, with an emphasis on Japanism reflected in the works of Western designers. The research methodology consisted of an analysis as well as a literature review. A total of 217 designs with Japanism characteristics were identified from the 2001 S/S collection to the 2011 S/S collection in Paris, Milano, New York, and London, and these were analyzed in terms of image, color details, pattern, and accessories. The research findings with regard to the characteristics of modern fashion designs that reflect Japanism were as follows. First, sensuality was projected by highlighting the erotic elements of Japanese clothing. Second, the underlying principles, styles, and elements of Japan's traditional clothing were embodied in a cross-cultural and eclectic manner that blurred the boundaries between styles by mix-and- matching the traditional and the contemporary, the East and the West, and different styles. Third, a variety of patterns, colors, accessories, and design techniques associated with Japanese traditional clothing played a critical role in creating flamboyant and decorative images in contemporary fashion. Fourth, the overlapping of the kimono style, the flat design that accentuates body curves, and the layered style has created a beautifully free-form fashion that demonstrates non-structural features.