• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.6
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• pp.257-264
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• 2021

This study established a numerical model capable of calculating the wave overtopping rate of coastal structures by nonlinear irregular waves using the FUNWAVE-TVD model, a fully nonlinear Boussinesq equation model. Here, a numerical model was established by coding the mean value approach equations of EurOtop (2018) and empirical formula by Goda (2009), and adding them as subroutines of the FUNWAVE-TVD model. The verification of the model was performed by numerically calculating the wave overtopping rate of nonlinear irregular waves on vertical wall structures and comparing them with the experimental results presented in EurOtop (2018). As a result of the verification, the numerical calculation result according to the EurOtop equation of this model was very well matched with the experimental result in all relative freeboard (R_c/H_mo) range under non-impulsive wave conditions, and the numerical calculation result of empirical formula was evaluated slightly smaller than the experimental result in R_c/H_mo < 0.8 and slightly larger than the experimental result in R_c/H_mo > 0.8. The results of this model were well represented in both the exponential curve and the power curve under impulsive wave conditions. Therefore, it was confirmed that this numerical model can simulate the wave overtopping rate caused by nonlinear irregular waves in an vertical wall structure.

• Knowledge Management Research
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• v.10 no.3
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• pp.1-16
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• 2009

Recent trends in business are characterized by recognition of the importance of knowledge assets. Especially, this phenomenon is receiving more momentum as our society goes digital rapidly. The concept of Knowledge Management has long been used as an effective way of restructuring the management process of a firm. In literature regarding knowledge management, a number of successful cases were reported, where knowledge-based management activities could dramatically enhance a firm's strategic performance for years. However, there exists very little research investigating the effect of knowledge management on corporate competitiveness. Researchers as well as practitioners need more rigorous results about such issues, especially how much the knowledge management strategic initiatives may have an influence on the firm's competitiveness. In this sense, we need an empirical study adopting statistical approaches due to the existence of abundant knowledge management case studies. To fill this research void, this study proposes a research model testing whether knowledge management activities could improve corporate competitiveness. We collected 321 valid questionnaires from participants in knowledge management activities in the tourism industry and applied a structural equation model. Empirical results showed that knowledge management activities have a positive impact on knowledge management efficiency and finally corporate competitiveness. We hope that this study will shed light on further rigorous studies considering tourism industry as a major strategic activity.

• The Journal of Information Systems
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• v.33 no.2
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• pp.27-45
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• 2024

Purpose The purpose of this study is to understand the important characteristics of mobile content services and to provide better content services to Chinese consumers by understanding consumer behavioral psychology about mobile content services and empirically analyzing research models with perceived usefulness, perceived enjoyment, customer attitudes, and repurchase intentions based on motivation theory. Design/methodology/approach Based on Deci(1975) Self-Determination Theory and Heijden(2004) research model, this study developed a research framework that includes perceived usefulness and perceived enjoyment to influence on repurchase intention. A questionnaire survey was conducted targeting Chinese consumers using mobile content services, and 272 valid responses were analyzed using Structural Equation Modeling (SEM). Findings According to the results of empirical analysis in this study, Chinese consumers were found to feel repurchase intention by positive impact of perceived usefulness and perceived enjoyment in the use of mobile content service. Chinese consumers still use mobile content a lot from a utilitarian perspective in relation to social life or job performance, and there is no positive effect on the use of mobile content related to perceived enjoyment. The results of this study provide the empirical results of a research model that integrates motivation theory and technology acceptance theory for the development of the mobile content industry in the future, and provide necessary insights for managers of companies that develop and distribute mobile content service.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.309-315
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• 2014

Summer cabbages in an alpine area are very sensitive to the fluctuations in supply and demand. Yield variability due to weather conditions dictates the market fluctuations of cabbage price. This study reports an empirical relationship based on weather conditions to estimate the growth and harvestable biomass of cabbages, factors that are critical for supply of summer cabbages. Based on experimental results testing sowing date effects over the two years from 1997 to 1998, a logistic equation was parameterized to predict leaf area expansion of summer cabbages. This logistic model for leaf area expansion was then combined with an empirical allometric relationship to predict total biomass. The final equation for estimating fresh weight accumulation of Chinese cabbage is given by: $$Fresh\;weight=3500/(1+{\exp}(5.175-1.153{\times}(6/(1+{\exp}(6.367-0.0064{\times}PHU)))))$$ Where PHU is potential heat units ($^{\circ}C$). The model performance was tested using weather data from 2003 to 2006 to predict fresh harvestable biomass. Overall the model performance was satisfactory with the correlation efficient ranging between 0.89 and 0.94 for each year.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.167-175
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• 2016

This study analyzed empirically the same data through SPSS statistic(regression analysis) and AMOS program(structural equation model) used for cause and effect analysis. The result of empirical analysis was as follows. The different outcome of coefficients and p-values were deducted. Especially, in the mediated effect testing, meanwhile, SPSS statistic(regression analysis) pictured mediated effect, AMOS program(structural equation model) did not picture mediated effect on the reject zone of null hypothesis(absolute t-value and C.R.-value were nearby 1.96). Eventually, this study showed that what program used determined the outcomes of coefficients and p-values(In particular, the outcomes were differentiated further in the increasing measurement error) though using the same data.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.172-172
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• 2020

In recent years, soil erosion has come to be regarded as an essential environmental problem in human life. Soil erosion causes various on- and off-site problems such as ecosystem destruction, decreased agricultural productivity, increased riverbed deposition, and deterioration of water quality in streams. To solve these problems caused by soil erosion, it is necessary to quantify where, when, how much soil erosion occurs. Empirical erosion models such as the Universal Soil Loss Equation (USLE) family models have been widely used to make spatially distributed soil erosion vulnerability maps. Even if the models detect vulnerable sites relatively well by utilizing big data related to climate, geography, geology, land use, etc. within study domains, they do not adequately describe the physical process of soil erosion on the ground surface caused by rainfall or overland flow. In other words, such models remain powerful tools to distinguish erosion-prone areas at the macro scale but physics-based models are necessary to better analyze soil erosion and deposition and eroded particle transport. In this study, the physics-based Surface Soil Erosion Model (SSEM) was upgraded based on field survey information to produce sediment yield at the watershed scale. The modified model (hereafter MoSE) adopted new algorithms on rainfall kinematic energy and surface flow transport capacity to simulate soil erosion more reliably. For model validation, we applied the model to the Doam dam watershed in Gangwon-do and compared the simulation results with the USLE outputs. The results showed that the revised physics-based soil erosion model provided more improved and reliable simulation results than the USLE in terms of the spatial distribution of soil erosion and deposition.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.3
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• pp.38-50
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• 1988

carried out to present a rheology model which is able to treat time-dependent properties of clay. The results were summarized as follow ; 1. The slope (a(e1)) of deviator stress in strain rate test was independent on axial strain, and pore water pressure was decreased with increment of strain rate. 2. The pore water pressure in a stress relaxation condition was not changed when the strain rate before stress relaxation was 0.05%/min., but it was increased with increment of time when the strain rate before stress relaxation was 0.2%/min 3. The greater the stress condition (q/qmax) and the strain rate before creep test became, the greater the increment rate of axial strain in creep test became. 4. SEKIGUCHI's constitutive equation was slightly overpredicted while empirical equation proposed in the study was well coincided with measured values. 5. The constitutive equation induced by a strain function could be dealed with a behavior of the pore water pressure increased with increment of elapsed time after primary consolidation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.6
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• pp.491-498
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• 2011

The structural vibration due to earthquake or outside impact causes serious problem for building safety. A dynamic model of a friction damper which can be constructed and installed easily is needed to reduce the vibration of the building. In this paper, the experimental equation of a circular friction damper is derived and designed for reduction of a earthquake vibration of a building. The developed experimental equation is defined to simply design the capacity on design of the circular friction damper based on the results of the performance test. Finally this experimental equation can be used for the design of a circular friction damper.

• Asia-Pacific Journal of Business
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• v.3 no.1
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• pp.10-16
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• 2012

India is having a high growth rate of Mobile subscribers which has opened up a new marketing channel of communication with customers. There is a need to study the factors affecting Mobile user's attitude towards Mobile marketing and the relationship between these factors. To study the mobile users attitude towards mobile marketing 489 mobile users opinion is taken on 12 statements for a period of 5 months. Using factor analysis method these 12 statements are grouped into 5 groups they are Mobile advertisement, Mobile Usability, Mobile Promotions, Mobiles shopping and Mobile Marketing. Confirmatory Factor Analysis (CFA) was performed to confirm the findings. SPSS Statistics 17.0 is used to conduct factor analysis and the validity of the model. Once the model was validated, SPSS Amos 18.0 was used to fit a model based on Structure Equation Model to analyze the factors affecting Mobile user's attitude and the relationship between these factors. The present study revealed that Mobile Advertisement and Mobile Sales Promotion are having positive effect on Mobile Marketing where as Mobile Shopping and Mobile Phone Usability is having negative effect on Mobile Marketing. The impact of indicators like Mobile Phone user's permission and personalization of Mobile Phone communication on Mobile Marketing are also discussed in this article.

• Asia-Pacific Journal of Business
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• v.3 no.2
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• pp.8-15
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• 2012

Mobile Entertainment is the new era in mobile communication. Mobile Entertainment service is a combination of games, music, videos, chatting and telecommunication which has created a wide market in India. There is a variation between male and female customers towards Mobile Entertainment services. This study is aimed at analyzing gender impact of attitude, subjective norm, perceived behaviour control intention and behaviour towards mobile entertainment services. The Theory of planned Behaviour (TPB) provided a framework. Total 566 male and 376 female mobile users of different age groups participated in the research. The data analysis was conducted in three-stages. First, reliability tests were performed. Upon satisfactory results, confirmatory factor analysis (CFA) is used to analysis convergent, concurrent and discriminant validity of the model. Once the model was validated Structural Equation Model (SEM) Multi-group analysis is used to find the impact of gender behaviour towards Mobile entertainment services. The results of the study confirmed that the model is viable in predicting variation in gender impact on mobile entertainment services. The findings have revealed that attitude, perceived behaviour control and intention has a significant impact on behaviour to use mobile entertainment but subjective norm has no significant impact on behaviour to use mobile entertainment.