• The Journal of Fisheries Business Administration
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• v.53 no.1
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• pp.55-72
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• 2022

The domestic catch of squid is decreasing every year. Import volume is increasing to replace these domestic products. Import volume is expected to increase in the future, so it is necessary to study import substitution. Therefore, in this study, after selecting frozen squid, which accounts for the majority of imported squid, as the target fish species, China, Chile and Peru, which account for the majority of frozen squid imports, will be selected as the target countries for analysis. Then, the demand function of squid is estimated using the Rotterdam model, the inverse Rotterdam model, AIDS and inverse AIDS, which are the simultaneous equation demand types, and then elasticity is derived. After that, these models are compared in terms of significance, theoretical fit and practical fit.

• Journal of Electrochemical Science and Technology
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• v.13 no.3
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• pp.377-389
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• 2022

The current global energy supply depends heavily on fossil fuels. This makes technology such as direct water splitting from harvesting solar energy in photoelectrochemical (PEC) systems potentially attractive due to its a promising route for environmentally benign hydrogen production. In this study, undoped and nickel-doped molybdenum oxide photoanodes (called photoanodes S₁ and S₂ respectively) were synthesized through electrodeposition by applying -1.377 V vs Ag/AgCl (3 M KCl) for 3 hours on an FTO-coated glass substrate immersed in molibdatecitrate aqueous solutions at pH 9. Scanning electron microscopy (SEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) were used for microstructural and compositional characterizations of the photoanodes. In addition, the optical and photoelectrochemical characterizations of these photoanodes were performed by UV-Visible spectroscopy, and linear scanning voltammetry (LSV) respectively. The results showed that all the photoanodes produced exhibit conductivity and catalytic properties that make them attractive for water splitting application in a photoelectrochemical cell. In this context, the photoanode S₂ exhibited better photocatalytic activity than the photoanode S₁. In addition, photoanode S₂ had the lowest optical band-gap energy value (2.58 eV), which would allow better utilization of the solar spectrum.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.6
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• pp.607-615
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• 2022

In this study, economic analysis program was developed for economic evaluation of hydrogen production, storage/delivery, and utilization technologies as well as overseas import of hydrogen. Economic analysis program can be used for the estimation of the levelized cost of hydrogen for hydrogen supply chain technologies. This program include five hydrogen production technology on steam methane reforming and water electrolysis, two hydrogen storage technologies (high compressed gas and liquid hydrogen storage), three hydrogen delivery technologies (compressed gas delivery using tube trailer, liquid hydrogen, and pipeline transportation) and six hydrogen utilization technologies on hydrogen refueling station and stationary fuel cell system. In the case of overseas import hydrogen, it was considered to be imported from five countries (Austraila, Chile, India, Morocco, and UAE), and the transportation methods was based on liquid hydrogen, ammonia, and liquid organic hydrogen carrier. Economic analysis program that was developed in this study can be expected to utilize for planning a detailed implementation methods and hydrogen supply strategies for the hydrogen economy road map of government.

• ETRI Journal
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• v.46 no.2
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• pp.184-193
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• 2024

This paper presents the performance evaluation of an amplify-and-forward (AF) relay-assisted multiuser multiple input-multiple output (MU-MIMO) downlink transmission system for correlated fading channels. The overall system performance was improved by incorporating a double-quadrature spatial modulation (DQSM) scheme. The bit error rate (BER) performance and detection complexity of the AF-MU-MIMO-DQSM system were analyzed and compared with those of a conventional AF-MU-MIMO system under the same conditions and parameters. The results showed that the correlated fading channel severely affected the performance of systems with higher spectral efficiency (SE). Considering an SE of 12 bpcu/user, the AF-MU-MIMO-DQSM system yielded a gain of up to 3 dB in BER performance compared with that of its conventional counterpart for the analyzed cases. In terms of detection complexity, the AF-MU-MIMO-DQSM system showed a reduction of up to 56 % compared with that of the conventional system for the optimal maximum likelihood detection criterion.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.53.1-53.1
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• 2015

The GMT-Consortium Large Earth Finder(G-CLEF) is one of the first light instruments at the Giant Magellan Telescope. The international consortium consists of five astronomical institutes including the Center for Astrophysics, the Observatories of Carnegie Institute, the University of Catolica in Chile, the University of Chicago, and Korea Astronomy and Space Science Institute, led by CfA. The extremely precise radial velocity capability is one of the principal instrumental feature of G-CLEF. The RV goal is 10 cm/s capable of detecting an Earth-like planet around a Sun-like host star. This high precision wavelength calibration stability requires a set of significantly tight optomechanical tolerances in the mechanical design of the Flexure Control Camera system. KASI is in charge of the Flexure Control Camera and the Calibration Light System for the G-CLEF spectrograph. In this presentation, we introduce the preliminary design and analysis results of the G-CLEF Flexure Control Camera.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.252-260
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• 2014

This study discussed the consumption and purchase behaviors of wine by hotel F&B employees based on cluster analysis. Consumption behavior was separated into two categories: place and frequency of drinking. Purchase behavior was divided into two as well: place and price of purchasing. In general, consumption behavior was more influenced by drinking place rather than price, with a wine bar being the most preferred place to drink. Further, purchase behavior was more dependent on the price than place, specifically mid-range priced wine. When selecting wine, "taste" was the most important quality considered for both consumption and purchase behaviors, followed by "price". In addition, "vintage" and "country/winery" were also considered important for consumption behavior. There was no further significant difference among selection attributes for wine quality in terms of purchase behavior. Overall satisfaction after wine consumption was 3.73. Frequency of drinking had a greater impact on overall satisfaction than drinking place. Overall satisfaction after wine purchasing was 3.72, and satisfaction level was greater when a wine was purchased at a wine bar rather than a general bar. With respect to country of origin, France, USA, Chile and Argentina wines all showed even variation among selection attributes for wine quality. However, Italian wine displayed a below average score under "vintage" and "bottle design", whereas Spanish wine did so under "brand". Lastly, Australian wine displayed the lowest scores for all selection attributes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.6
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• pp.821-831
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• 2019

The 9.12 earthquake (2016.9.12., M_L=5.8) and Pohang (2017.11.15., M_L=5.4) caused social and economic damage, resulting in a greater public interest in earthquakes than in the past. In the U.S., Japan and Chile, which have high frequency of earthquakes, infrastructure facilities are already managed based on probabilistic seismic hazard analysis (PSHA) and ground motion prediction equation (GMPE) to prepare for and respond to seismic disasters. In South Korea, the aforementioned PSHA and GMPE models have been developed independently through individual researchers. However, the limited disclosure of basic data, calculation methods, and final results created during the model development poses a problem of deploying new data without updating the earthquake that occurs every year. Therefore, this paper describes how to create flatfile, which is the basic data of GMPE, and how to process for seismic waves, and how to create intensity measures.

• Imaging Science in Dentistry
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• v.45 no.2
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• pp.95-101
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• 2015

Purpose: This study used cone-beam computed tomography (CBCT) to characterize mandibular molar root and canal morphology and its variability in Belgian and Chilean population samples. Materials and Methods: We analyzed the CBCT images of 515 mandibular molars (257 from Belgium and 258 from Chile). Molars meeting the inclusion criteria were analyzed to determine (1) the number of roots; (2) the root canal configuration; (3) the presence of a curved canal in the cross-sectional image of the distal root in the mandibular first molar and (4) the presence of a C-shaped canal in the second mandibular molar. A descriptive analysis was performed. The association between national origin and the presence of a curved or C-shaped canal was evaluated using the chi-squared test. Results: The most common configurations in the mesial root of both molars were type V and type III. In the distal root, type I canal configuration was the most common. Curvature in the cross-sectional image was found in 25% of the distal canals of the mandibular first molars in the Belgian population, compared to 11% in the Chilean population. The prevalence of C-shaped canals was 10% or less in both populations. Conclusion: In cases of unclear or complex root and canal morphology in the mandibular molars, CBCT imaging might assist endodontic specialists in making an accurate diagnosis and in treatment planning.

• ALGAE
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• v.27 no.2
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• pp.109-114
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• 2012

Water motion is one of the main drivers in morphological variability in species within de order Laminariales, and most of our current knowledge is based on subtidal populations. $Eisenia$ $arborea$ is a dominant kelp species in the North Pacific, widely distributed along the Baja California Peninsula from mid intertidal down to subtidal areas. This species presents great variability in the intertidal zone but it has not been yet evaluated such variability according to wave exposure. The present work also identifies the spatial / temporal variation, particularly respect to the presence of stipes without medulla (hollow stipes) a feature common among other brown seaweeds. We evaluated the effects of wave action in morphological variation of intertidal $Eisenia$ $arborea$ (Laminariales, Ochrophyta) at Punta Eugenia. The spatial and temporal variation sampling was surveyed between February, May, July, and August 2004 in the intertidal of Punta Eugenia, Baja California Sur. Our results have shown that exposed sites correlate with increased length and width of stipes as compared to more protected sites. Hollow stipes frequency changed more in association with temporal variation than with spatial heterogeneity suggesting nutrient limitation for thalli development. Our results suggest that $Eisenia$ $arborea$ compensate by morphological modifications the stress of living in the intertidal zone by showing larger stipes. Hollow stipes might be are also a mechanical adaptation to increase survival in high energy environments.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.39-48
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• 2008

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are ubiquitous and can contaminate the food chain. A study monitoring PCDD/Fs in imported meat was conducted at the National Veterinary Research and Quarantine Service (NVRQS, Republic of Korea) in order to maintain food safety from the bioaccumulative PCDD/Fs. Seventeen PCDD/Fs with toxic equivalency factors (TEFs) established by World Health Organization (WHO, 1998) were analyzed in imported beef, pork, and chicken by high resolution gas chromatography/mass spectrometry (HR-GC/MS). Results of the monitoring for the last 5 years are presented. The levels of PCDD/Fs were similar to other studies except two unusually high concentrations in pork and beef. Excessive levels greater than the Korean provisional maximum residue limit of PCDD/Fs were found in a sample of pork imported from Chile and a sample of beef imported from U.S, and those products were rejected and returned. There was no obvious trend or differences with respect to time or origin of meat in this study.