• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.718-733
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• 2021

A prediction method, based on the Morison equation as well as Froude-Krylov formula, is presented to simulate the loads acting on the columns and caissons of the semi-submersible platform induced by Internal Solitary Wave (ISW) respectively. Combined with the experimental results, empirical formulas of the drag and inertia coefficients in Morison equation can be determined as a function of the Keulegan-Carpenter (KC) number, Reynolds number (Re) and upper layer depth h₁/h respectively. The experimental and calculated results are compared. And a good agreement is observed, which proves that the present prediction method can be used for analyzing the ISW-forces on the semi-submersible platform. Moreover, the results also demonstrate the layer thickness ratio has a significant effect upon the maximum horizontal forces on the columns and caissons, but both minimum horizontal and vertical forces are scarcely affected. In addition, the incoming wave directions may also contribute greatly to the values of horizontal forces exerted on the caissons, which can be ignored in the vertical force analysis.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.4
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• pp.429-453
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• 2022

Numerical modeling and scenario composition are needed to characterize the geological environment of the disposal site and analyze the long-term evolution of natural barriers. In this study, processes and features of the hydro-mechanical behavior of natural barriers were categorized and represented using the interrelation matrix proposed by SKB and Posiva. A hydro-mechanical coupled model was evaluated for analyzing stress field changes and fracture zone re-activation. The processes corresponding to long-term evolution and the hydro-mechanical mechanisms that may accompany critical processes were identified. Consequently, practical numerical methods could be considered for these geological engineering issues. A case study using a numerical method for the stability analysis of an underground disposal system was performed. Critical stress distribution regime problems were analyzed numerically by considering the strata's movement. Another case focused on the equivalent continuum domain composition under the upscaling process in fractured rocks. Numerical methods and case studies were reviewed, confirming that an appropriate and optimized modeling technique is essential for studying the stress state and geological history of the Korean Peninsula. Considering the environments of potential disposal sites in Korea, selecting the optimal application method that effectively simulates fractured rocks should be prioritized.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.553-559
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• 1998

Introduction: The most dramatic application of hypothermia in cardiac surgery is in deep hypothermic circulatory arrest(DHCA). Because man in natural circumstances is never exposed to this extreme hypothermic condition, one of the controversial aspects of clinical hypothermia is appropriate acid-base management($\alpha$-stat versus pH-stat). This study aims to compare $\alpha$-stat with pH-stat for: (1) brain cooling and re-warming speed during hypothermia induction and re-warming by cardiopulmonary bypass (CPB); (2) cerebral perfusion, metabolism, and their coupling; and (3) the extent of development of cerebral edema after circulatory arrest, in young pigs. Materials & Methods: Fourteen young pigs were assigned to one of two strategies of gas manipulation. Cerebral blood flow was measured with a cerebral venous outflow technique. After a median sternotomy, CPB was established. Core cooling was initiated and continued until nasopHaryngeal temperature fell below $20^{\circ}C$. The flow rate was set at 2,500 ml/min. Once their temperatures were below $20^{\circ}C$, the animals were subjected to DHCA for 40 mins. During cooling, acid-base balance was maintained according to either $\alpha$-STAT or pH-STAT strategies. After DHCA, the body was re-warmed to normal body temperature. The animals were then sacrificed, and their brains measured for edema. Cerebral perfusion and metabolism were measured before the onset of CPB, before cooling, before DHCA, 15 mins after re-warming, and upon completion of re-warming. Results & Conclusion: Cooling time was significantly shorter with $\alpha$-stat than with pH-stat strategy, while there were no significant differences in rewarming time between the two groups. Nosignificant differences were found in cerebral blood flow, metabolic rate, or flow/ metabolic rate ratio between two groups. Temperature-related differences were significant in cerebral blood flow, metabolic rate, and flow/metabolic rate ratio within each group. Brain water content showed no significant differences between two groups.

• Information Systems Review
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• v.13 no.3
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• pp.99-121
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• 2011

With the advancement of mobile information technology, the era of smart work emerges as a means for enabling us to overcome temporal and spatial constraints. Thanks to smart mobile devices with seamless access, organizations can assign tasks to employees and provide services to the appropriate customers in mobile environments. In addition, smart work facilitates the improvement of coordination and collaboration among individuals and groups performing organizational tasks. The dramatic performance improvement is manifest by utilization of smart work in organizations. Therefore, the interest in the introduction of smart work is growing. With the lens of time-geography, this study investigates what makes smart work successful. This research, especially, concentrates on the processes for overcoming the temporal and spatial constraints in the field. A case study of the Seoul Metropolitan Rapid Transit Talk and Flash (SMRT T&F) is developed and analyzed through the framework of time-geography and the implementation processes and success factors of SMRT T&F are investigated.

• Fashion & Textile Research Journal
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• v.14 no.5
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• pp.701-712
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• 2012

This study examines the various expressions and immanent value of fashion and beauty style based on Craig Owens's Allegory theory. I analyzed four application elements of Borrow, Site Specificity, Accumulation of Strategy, and Hybridization in? Ladygaga's Music Videos. The results are as follows. 'Borrow' presents a kitsch style and playful Pop-art style, transformation of gender from Mini Mouse body suit, telephone headpiece, and can hair. 'Site specificity' presents the temporarity of fashion material through rebirth, aging, natural extinction from the chain over the black jump suit, crime scene tape, and skull-face makeup with masculine style. 'Accumulation of strategy' presents a futuristic chic fashion style from a layered style, retrospective fashion, repetition and duplication in Music Videos. It shows the physical beauty of an Asian warrior style in Poker Face. 'Hybridization' present Cyborg feminism and 'Will of Power' from iPOD LCD glasses and Pyro-Bra. The Pyro-Bra represents how the female body can be used as a weapon in the outfits of Lady Gaga. In addition, Immanent value is as follows. Textual interaction with high art is accomplished through a combination of contemporary social and cultural significance to understand the cultural code and to extend the value. Combined with high culture, popular music genre is accomplished through musical appreciation by a woman in fashion styling and sensual pleasures of the body as a tool to express a sublime advantage. Fashion style is accomplished by overcoming a self-transcendent body image representation. The way in which mutual coupling dismantling, destruction, and uncertainty is to re-launch the static, with a pluralistic context of Textuality.

• Journal of Korean Society of Steel Construction
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• v.20 no.2
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• pp.289-301
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• 2008

Double skin composite (DSC) wall is a structural wall that is filed with concrete between two steel plate skins connected by tie bars. This type of wall was developed to enhance the structural performance of wall, to reduce wall thickness, and to enhance constructibility, eliminating the use of formwork and re-bars. In this study, cyclic tests were performed to investigate the inelastic behavior and earthquake resistance of isolated and coupled DSC walls with rectangular and T-shapedcross-sections. The DSC walls showed stable cyclic behaviors, exhibiting excellent energy dissipation capacity. The te st specimens failed by the tensile fracture of welded joints at the wall base and coupling beam and by the severe local buckling of the steel plate. The deformation capacity of the walls varied with the connection details at the wall base and their cross-sectional shapes. The specimens with well-detailed connections at the wall base showed relatively god deformation capacity ranging from 2.0% to 3.7% drift ratio. The load-carrying capacities of the isolated and coupled wall specimens were evaluated considering their inelastic behavior. The results were compared with the test results.

• Proceedings of the Korea Database Society Conference
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• 2010.06a
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• pp.165-180
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• 2010

This study takes a holistic approach to understanding the diffusion of IPTV services by combining the adoption-diffusion model and the use-diffusion model of innovation. IPTV service, a leading Digital converged application coupling media content with telecom, has been recently launched commercially in Korea. We created a structural model of adoption-diffusion, using the perceived ease-of-use and usefulness of TAM(Technology Acceptance Model) as mediating variables, and a structural model of use-diffusion, with the rate of use and the variety of use as mediating variables. To empirically analyze these models, non-users of IPTV were surveyed using the adoption-diffusion model to identity factors influencing their intention to subscribe to the service. Meanwhile, users of IPTV were surveyed using the use-diffusion model to determine the factors that influence their satisfaction with the service and their intention to fe-use it. Under the adoption-diffusion model, we found that trialability, household innovativeness and perceived risk were the determinants of user satisfaction with IPTV, and perceived ease-of-use, the mediating factors. Under the use-diffusion model, complementarity and communication were shown to be the determinants of users' satisfaction with IPTV, and variety of use, the mediating factor. We also found that consumers' intention to re-use IPTV was strongly influenced by its relative advantage and perceived risk.

• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1034-1038
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• 2007

Hypericin (HyH) is a substance which is isolated a medicinal herb, Hypericum perforatum L., commonly known as St. John's Wort. Hypericum erectum is a long-lived herb that is distributed in Korea. Cloned HyH genes H. erectum of were conformed by sequencing. The cDNA Hyp-1 sequence has 732 bp with an open reading frame of 567. Thus coding for a protein of 152 amino acid residues. A BLAST re-search using the deduced nucleotide sequences in HyH gene produced significant alignments with the H. perforatum. Sequences in HyH gene showed significant homology with Rubus idaeus putative allergen Rub-i-1 mRNA, Protein sequence comparisons revealed significant homology between Hyp-1 and the phenolic oxidative coupling protein hyp-1 of H. perforatum (98%). Additionally, Hyp-1 showed sig-nificant homology with various other classes of allergens, including Pru-av-1 (62%) from Prunus avium and allergen Bet-vl-Sc3 from Betula pendula (60%). Thus, the result of this study may offer an important information to establish an assay system for chemicals of the herbal medicines for H. erectum as well as H. perforatum.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.257-258
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• 2012

The SERS spectra of 4-aminobenzenethiol (ABT) have served as the "probe" molecule, which have helped spectroscopists to build up the electromagnetic (EM) and chemical (CHEM) enhancement mechanisms. In particular, the b2-peaks (9b, 3, and 19b) of the SERS spectra of ABT have been attributed to arise from the vibronic charge-transfer (CT) between Au or Ag surface and the ABT. Quite recently, however, Tian and co-workers [1] claimed that the b2-peaks are not the CT-enhanced spectra of ABT. Instead, these peaks arise from the 4,4'-dimercaptoazobenzenes (DMABs) that are produced by the oxidative coupling of two ABTs. Their claim is under intense debate currently. Herein, we studied spatially and temporally resolved SERS spectra of ABTs on Ag thin film (thickness of 10 nm), to investigate such claim. Herein, we present a series of additional evidences that strongly support that the b2 intensities of ABTs do not arise from the CT-enhancement: (1) the b2-peaks can be locally "activated" (i. e. turned on) irreversibly with focused laser radiation; (2) the TOF-SIM spectrometry on the activated region show depletion of ABT-Ag+ ions; and finally (3) the spatially resolved FT-IR spectra of the activated region show two pronounced peaks at 1377 cm-1 and 1460 cm-1, both of which can be assigned to the stretching mode of N=N bond. While the result does not disprove the existence of CT or CHEM enhancement in general, the results do show that previous interpretations of the spectra of ABTs should be re-interpreted.

• Journal of Magnetics
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• v.21 no.2
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• pp.215-221
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• 2016

We conducted a phased electromagnetic forming process analysis (EFPA) over time through a coupling of electromagnetic analysis and structural analysis. The analysis is conducted through a direct linkage between electromagnetic analysis and structural analysis. The analysis process is repeated until the electric current is completely discharged by a formed coil. We calculate the forming force that affects the workpiece using MAXWELL, a commercial electromagnetic finite element analysis program. Then, we simulate plastic behavior by using the calculated forming force data as the forming force input to ANSYS, a commercial structure finite element analysis program. We calculate the forming force data by using the model shape in MAXWELL, a commercial electromagnetic finite element analysis program. We repeat the process until the current is fully discharged by the formed coil. Our results can be used to reduce the error in data transformation with a reduced number of data transformations, because the proposed approach directly links the electromagnetic analysis and the structural analysis after removing the step of the numerical analysis of a graph describing the forming force, unlike the existing electromagnetic forming process. Second, it is possible to simulate a more realistic forming force by keeping a certain distance between nodes using the re-mesh function during the repeated analysis until the current is completely discharged by the formed coil, based on the MAXWELL results. We compare and review the results of the EFPA using the peak value of the forming force that acts on the workpiece (which is the existing analysis method), and the proposed phased EFPA over time approach.