• Journal of Ocean Engineering and Technology
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• v.25 no.3
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• pp.66-72
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• 2011

This is the fourth of a series of companion papers dealing with the mechanical property reductions of various marine structural steels. Even though a reduction of the elastic modulus according to temperature increases has not been obtained from experiments, high temperature experiments from room temperature to $900^{\circ}C$ revealed that initial the yield strength and tensile strength are both seriously degraded. The mechanical properties obtained from high temperature experiments are compared with those from EC3 (Eurocode 3). It is found that the high temperature test results generally comply with the prediction values by EC3. Based on the prediction of EC3, time domain nonlinear finite element analyses were carried out for a blast wall installed on a real FPSO. After applying the reduced mechanical properties, corresponding to $600^{\circ}C$ to the FE model of the blast wall, more than three times the deflections were observed and it was observed that most structural parts experience plastic deformations exceeding the reduced yield strength at the high temperature. It is noted that a protection facility such as PFP (passive fire protection) should be required for structures likely to be directly exposed to fire and explosion accident.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.162-177
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• 2020

Background: Ecologists have achieved much progress in the study of mechanisms that maintain species coexistence and diversity. In this paper, we reviewed a wide range of past research related to these topics, focusing on five theoretical bodies: (1) coexistence by niche differentiation, (2) coexistence without niche differentiation, (3) coexistence along environmental stress gradients, (4) coexistence under non-equilibrium versus equilibrium conditions, and (5) modern perspectives. Results: From the review, we identified that there are few models that can be generally and confidently applicable to different ecological systems. This problem arises mainly because most theories have not been substantiated by enough empirical research based on field data to test various coexistence hypotheses at different spatial scales. We also found that little is still known about the mechanisms of species coexistence under harsh environmental conditions. This is because most previous models treat disturbance as a key factor shaping community structure, but they do not explicitly deal with stressful systems with non-lethal conditions. We evaluated the mainstream ideas of niche differentiation and stochasticity for the coexistence of plant species across salt marsh creeks in southwestern Denmark. The results showed that diversity indices, such as Shannon-Wiener diversity, richness, and evenness, decreased with increasing surface elevation and increased with increasing niche overlap and niche breadth. The two niche parameters linearly decreased with increasing elevation. These findings imply a substantial influence of an equalizing mechanism that reduces differences in relative fitness among species in the highly stressful environments of the marsh. We propose that species evenness increases under very harsh conditions if the associated stress is not lethal. Finally, we present a conceptual model of patterns related to the level of environmental stress and niche characteristics along a microhabitat gradient (i.e., surface elevation). Conclusions: The ecology of stressful systems with non-lethal conditions will be increasingly important as ongoing global-scale climate change extends the period of chronic stresses that are not necessarily fatal to inhabiting plants. We recommend that more ecologists continue this line of research.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.228-229
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• 2007

Container cranes are vulnerable structure to difficult weather conditions because there is no shielding facility to protect them from high wind This study carried out to analyze the wind load have an effect on container crane according to a wind direction variation The container crane for this research is a model of a 61-ton class tint used broadly in the current ports. The dimension of an external fluid field set up 500m ${\times}$ 200m. In this study, Mean wind load conformed to the 'Design Criteria of Wind Load' in 'Load Criteria of Building Structures' and an external fluid field divided in interval of 10 degrees to analyze effect according to a wind direction From there, we carried out to the computation fluid dynamic analysis using a CFX-10 Therefore as consequence of computation fluid dynamic analysis and wind velocity experiment make a comparative study, we analyzed a wind load for construction design if container crane.

• Journal of Oriental Neuropsychiatry
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• v.24 no.3
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• pp.309-320
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• 2013

Objectives : There is a possibility LRE as remedy in Alzheimer disease (AD), but it's nerve protection effect and mechanism have to be elucidate. In this research, we applied LRE on $A{\beta}_{25-35}$ pre-treated SH-SY5Y cells, to find out the nerve protection effect and mechanism in AD cell model. Methods : We tried to confirm that effect by experimenting with 20, 50, and $100{\mu}g/ml$ concentration of LRE as a medicine. Next experiment, we assessed damage effect which induced $A{\beta}_{25-35}$, known to cause AD, on SH-SY5Y cell. In addition, cellular viability test is executed under $H_2O_2$ treatment condition in a SH-SY5Y cell. Results : 1. In $A{\beta}_{25-35}$ treated SH-SY5Y cell, LRE exhibited an anti-phosphorylation effect about tau protein, JNK, and IKB. 2. LRE prevent nerve cell apoptosis, which indued $A{\beta}_{25-35}$ and oxidative stress, modify JNK engaged synaptic structure and $NF{\kappa}B$ induced p75-neurotrophin receptor polymorphism. Conclusions : We found that LRE prevented oxidative stress-induced cellular destruction, for example, increased SOD activity of $A{\beta}_{25-35}$ treated SH-SY5Y cell and reduced toxicity of oxygen free radical. Consequently, the ingredients of LRE have a role as a catalyzer for $A{\beta}_{25-35}$ clearance and as scavenger for active oxygen free radical.

• Journal of Embryo Transfer
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• v.31 no.4
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• pp.313-318
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• 2016

The aim of this study was to identify quantitative trait loci (QTLs) influencing teat number traits in an $F_2$ intercross between Landrace and Korean native pigs (KNP). Three teat number traits (left;right;and total) were measured in 1105 $F_2$ progeny. All experimental animals were genotyped with 173 informative microsatellite markers located throughout the pig genome. We detect that seven chromosomes harbored QTLs for teat number traits: genome regions on SSC1;3;7;8;10;11;and 13. Six of fourteen identified QTL reached genome-wide significance. In SSC7;we identified a major QTL affecting total teat number that accounted for 5.6 % of the phenotypic variance;which was the highest test statistic (F-ratio = 61.1 under the additive model;nominal $P=1.3{\times}10^{-14}$) observed in this study. In this region;QTL for left and right teat number were also detected with genome-wide significance. With exception of the QTL in SSC10;the allele from KNP in all 6 identified QTLs was associated with decreased phenotypic values. In conclusion;our study identified both previously reported and novel QTL affecting teat number traits. These results can play an important role in determining the genetic structure underlying the variation of teat number in pigs.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.1
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• pp.65-86
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• 2018

This study focuses on the relationship structure of SMEs with outsourcing based on buyer-supplier relationships and aims to test the role of trust management and mutual growth in the activities of SMEs. Trust management and mutual growth have a context in which the outsourcing type is determined through the company's slack resources, partnership relations, and buyer-supplier relationship. In this context, research hypotheses were set up, research model was designed and an empirical analysis was conducted by using structural equation modeling. For the empirical analysis, hypotheses were tested using data obtained from questionnaires of 206 SMEs nationwide. As a result, trust management and mutual growth have a significant effect on outsourcing type and performance, and mediation effect of cooperation relationship and buyer-supplier relationship was in the process.

• Korean Journal of Human Ecology
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• v.14 no.1
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• pp.143-153
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• 2005

The purpose of this research is to study face images according to the difference of facial shape and make-up. A variety of face images can be formulated by computer graphic simulation, combining numerously different facial shapes and make-up styles. In order to check out the diverse images by make-up styles, we applied five forms of eye brows, two types of eye shadows, and three lip shapes to the round-shaped face of a model. The question sheet, used with a operational stimulant in the experiment, contained 28 articles, composed of a pair of bi-ended adjective in 7 point scale. Data were analyzed using Varimax perpendicular rotation method, Duncan's Multiple Range Test, and Three-way ANOVA. After comparing various results of make-up application to various face types, we could find that facial shape, eye-brows, eye-shadow, and lip shapes influence interactively on total facial images. As a result of make-up image perception analyses, a factor structure was divided into mildness, modernness, elegance, and sociableness. Speaking of make-up image in terms of those factors, round form make-up style showed the highest level of mildness. Upward and straight style of make-up had the highest of modernness. Elegance level went highest when eye shadow style was round form and lip style was straight. Lastly, an incurve lip make-up style showed the highest of sociableness.

• Journal of the Korean Regional Science Association
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• v.32 no.1
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• pp.67-82
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• 2016

This study aims to test the spatial mismatch hypothesis by exploring the relationship between income and commuting time in Seoul, Korea. For this purpose, we analyze the commuting times of individuals who commute to Seoul, using the data for the metropolitan household survey. We employed a hierarchial linear model(HLM) to capture the effects of both individual attributes and regional attributes, and their interactions. The results show that the commuting time decreases with household income controlling for the regional attributes, and the effect of income increases with the housing price of the location of a commuter's firm. This implies that the spatial mismatch holds for Seoul as follows: Lower personal income and housing affordablility extend individuals' commuting times, and the destinations' characteristics such as housing type and land use also have impacts on commuting time. These results have some policy implications for achieving social equity in terms of spatial structure of the city.

• Journal of Distribution Science
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• v.15 no.2
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• pp.91-100
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• 2017

Purpose - Domestic franchise market has been grown steadily, reaching 50 trillion won in sales and 3,360 franchise headquarters in 2014. A franchise system is an effective business system for the franchisees to lower the failure rate due to the fact that the inexperienced entrepreneurs are supported by their headquarters through the franchisee contract. However, there are also conflicts between franchiser and franchisee behind the quantitative growth of domestic franchise industry. Therefore, it is very important to structure the causes of conflicts and to examine the effect of factors on the relationship commitment and performances. Research design, data, and methodology - In this study, the author divides the composite incompatibility between the franchise and the franchisee into goal incongruity, domain dissensus, and perceptual differences, and examines each dimension to the relationship with commitment and performances. To verify the proposed research model and test hypotheses, the author selected 200 franchise responses in food and beverage industry. The data were analyzed using SPSS 18.0 and AMOS structural equation modeling program. Results - The empirical findings provide goal incongruity and perceptual differences have a negative effect on the affective commitment, but not the calculative commitment. In addition, affective commitment and calculative commitment are found to have a positive effect on re-contractual intention and extended brand shop running intention, respectively. Affective commitment have a stronger effect on re-contractual intention than calculative commitment. Conclusions - First of all, the fact that goal incongruity and perceptual differences negatively affect the affective commitment, but it does not affect the calculative commitment. It means the relationship commitment in distribution channel are multi-dimensional concept that may be attributed to emotional or affective dimensions but may exist in terms of necessity or power-dependence. Second, the level of relationship commitment such as affective and calculative commitment to franchise headquarters positively affects the re-contractual intention and franchiser's extend brand shop running intention suggest that franchiser should encourage and support existing franchisee's commitment. Third, the fact that affective commitment has a greater effect on relationship performance than calculative commitment means to induce franchisee's affective commitment and to prevent the inconsistency between goals and perceptual differences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.718-724
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• 2017

Considerable efforts have been made to expand the boundaries of domestic offshore plant industries, which have focused on the construction of the structures, to the engineering field. On the other hand, time domain analysis, which is one of the most important areas in designing floating offshore plants, relies mainly on the information given by foreign companies. As an early design of the Dynamic Positioning System (DPS) is mostly conducted by several specialized companies, domestic ship builders need to spend time and money to reflect the analysis into the hull shape design. This paper presents the framework required to analyze time domain performance of floating type offshore structures, which are equipped with DPS. To easily perform time domain analysis, framework generates the required input data for the solver, and is modularized to test the control algorithm and performance of a certain DPS. The effectiveness of the developed framework was verified by a simulation with a model ship and the total time for the entire analysis work was reduced by 50% or more.