• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.3
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• pp.264-272
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• 2019

The aim of this study is to analyze the relationship between international oil price as a fuel cost in overseas fisheries and skipjack tuna price as a part of main products in overseas fisheries using monthly time series data from 2008 to 2017. The study also tried to analyze the change of fishing profits by fuel cost. For a time series analysis, this study conducted both the unit-root test for stability of data and the Johansen cointegration test for long-term equilibrium relations among variables. In addition, it used not only the Granger causality test to examine interactions among variables, but also the Vector Auto Regressive (VAR) model to estimate statistical impacts among variables used in the model. Results of this study are as follows. First, each data on variables was not found to be stationary from the ADF unit-root test and long-term equilibrium relations among variables were not found from a Johansen cointegration test. Second, the Granger causality test showed that the international oil prices would directly cause changes in skipjack tuna prices. Third, the VAR model indicated that the posterior t-2 period change of international oil price would have an statistically significant effect on changes of skipjack tuna prices. Finally, fishing profits from skipjack would be decreased by 0.06% if the fuel cost increases by 1%.

• Journal of Korean Home Economics Education Association
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• v.18 no.4 s.42
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• pp.55-65
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• 2006

This study examined the effects of self-esteem, relationships with parents and peer relationships on adolescents' internet addiction among middle school students. Data were derived from 439 students in the 8th grade. The results of the study showed that internet addiction was higher in male adolescents compared to female adolescents. This study identified that internet addiction of male adolescents was affected by low levels of self-esteem and peer relationships. Poor relationship with parents and low levels of peer relationships were factors influencing internet addiction among female adolescents. It might be useful to improve interpersonal relations based on peers' interactions and to strengthen family relations in order to prevent internet addiction. In addition, it would help to develop educational programs and youth programs for preventing adolescents' internet addiction.

• Journal of Korea Water Resources Association
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• v.45 no.1
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• pp.39-52
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• 2012

Surface-subsurface interactions are an intrinsic component of the hydrologic response within a watershed. In general, these interactions are considered to be one of the most difficult areas of the discipline, particularly for the modeler who intends simulate the dynamic relations between these two major domains of the hydrological cycle. In essence, one major complexity is the spatial and temporal variations in the dynamically interacting system behavior. The proper simulation of these variations requires the need for providing an appropriate coupling mechanism between the surface and subsurface components of the system. In this study, an approach for modelling surface-subsurface flow and transport in a fully intergrated way is presented. The model uses the 2-dimensional diffusion wave equation for sheet surface water flow, and the Boussinesq equation with the Darcy's law and Dupuit-Forchheimer's assumption for variably saturated subsurface water flow. The coupled system of equations governing surface and subsurface flows is discretized using the finite volume method with central differencing in space and the Crank-Nicolson method in time. The interactions between surface and subsurface flows are considered mass balance based on the continuity conditions of pressure head and exchange flux. The major module consists of four sub-module (SUBFA, SFA, IA and NS module) is developed.

• Acta Via Serica
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• v.9 no.1
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• pp.67-90
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• 2024

India, Southeast Asia in general, and Siam in particular share a long history of cultural and commercial relations. Located in each other's extended neighbourhood, India and Thailand have a shared maritime boundary in the Andaman Sea. Situated in the strategic position, midway between West Asia on the one hand and East Asia on the other, India and Siam combined played a significant role in the maritime transactions in Asia and beyond. The geographical proximity between India and Siam led to multifaceted maritime interactions and exchanges. Siam was in the Indian sphere of cultural, religious, philosophical, technical, and linguistic influence much before the Common Era. The cultural and mercantile networks between India and Siam are well-attested by archaeological and literary sources. The archaeological findings in Siam and other Southeast Asian countries have revealed the dynamic trade and cultural exchange between India and Southeast Asia since the pre-Common Era. The Takola (modern Takua Pa) area served as a more suitable landing place for Indian merchants and there existed the settlement of the Indian mercantile community. Ligor (Nakhon Si Thammarat), Jaya (Chaiya), Patalung (Phatalung), U Thong, Ban Don Tha Pet, Ban U Taphao, Khao Sam Kaeo, and many other sites in Siam have brought to light a large variety of objects which demonstrate that ancient Siam had close mercantile contact with India as well as the Mediterranean world and China. The paper discusses in detail the cultural and trade links between India and Siam and their impact on the Maritime Silk Road.

• World Technopolis Review
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• v.3 no.1
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• pp.39-54
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• 2014

Recently, investment to basic science has been increased and infrastructure of science and technology has been expanded in developed countries like U.S.A, UK and Japan to foster high-tech industries. Science and research parks are built and under operation to acquire national competitive power and to activate regional economy over the world today. It is argued that more synergy effects are generated when science and research parks are operated in cooperation with related organizations and facilities such as firms, universities, research institutes and governments than it is operated by one organization. The aim of this paper is to develop a governance model of science and research parks. One comprehensive model and three individual governance models were developed according to the structure and relations of industry-science/research park-supporting organization interactions. When governance model of science and research parks is established and properly managed, national development capacity would be greatly enhanced through the acceleration of technology transfer, industrial production rise and enhancement of efficiency in the area of R&D and supporting system etc. One of the key factors in building governance system for science and research parks is establishing a control tower that supervises governance system comprehensively and systematically.

• Asian Journal of Business Environment
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• v.11 no.4
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• pp.17-29
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• 2021

Purpose: The aim of this study is to explore the dynamic linkage between conditional stock market volatility and macroeconomic uncertainty of Bangladesh. Research design, data, and methodology: This study uses monthly data covering the time period from January 2005 to December 2018. A comprehensive set of macroeconomic variables, namely industrial production index (IP), consumer price index (CPI), broad money supply (M2), 91-day treasury bill rate (TB), treasury bond yield (GB), exchange rate (EX), inflow of foreign remittance (RT) and stock market index of DSEX are used for analysis. Symmetric and asymmetric univariate GARCH family of models and multivariate VAR model, along with block exogeneity and impulse response functions, are implemented on conditional volatility series to discover the possible interactions and causal relations between macroeconomic forces and stock return. Results: The analysis of the study exhibits time-varying volatility and volatility persistence in all the variables of interest. Moreover, the asymmetric effect is found significant in the stock return and most of the growth series of macroeconomic fundamentals. Results from the multivariate VAR model indicate that only short-term interest rate significantly influence the stock market volatility, while conditional stock return volatility is significant in explaining the volatility of industrial production, inflation, and treasury bill rate. Conclusion: The findings suggest an increasing interdependence between the money market and equity market as well as the macroeconomic fundamentals of Bangladesh.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.764-769
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• 2007

This paper is studied the noise and vibration characteristics analysis of the three-phase induction AC motor of the electrical forklift. And we suggest the method which the reduction orders the noise and vibration to be the mechanical. In other to investigate these characteristics, we considered the mechanical characteristics, the electromagnetic effects, and these interactions. In mechanical, we studied the characteristic of the stator, the bearing supported condition of the rotor, and the sound radiation. In electronically, this paper is considered the harmonic effect which is related the magnetic motive force (mmf) with respect to the characteristic of the slot number of the rotor and the stator and the pole number of the motor. Finally we investigated the overall noise and vibration of the induction motor by relations between the electronically harmonic and the mechanical resonance of the stator. By the analysis of the generally three-phase induction motor, we suggest the design methodology to low noise and vibration.

• Journal of Information Technology Applications and Management
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• v.23 no.1
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• pp.1-23
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• 2016

Social commerce (s-commerce) is a subset of e-commerce and uses social media for social interactions. Although s-commerce has been rapidly growing, disputes between some s-commerce firms and their consumers often occur over issues such as poor customer services, incorrect product information, and late refunds. In order for s-commerce to continuously grow, s-commerce firms need to build consumer-trust in their transaction process to minimize their consumers' uncertainty. The purpose of this study is to examine the relationships between the multidimensional trust (ability, integrity, benevolence) and the intention of continuous use of s-commerce. Moreover, this study presents antecedent factors needed for trust-building by applying the characteristics of s-commerce, and verifies the relations between the variables. We test and validate the research model and related hypotheses using structural equation modeling based on a survey done on 428 people who have previous experience with s-commerce. The result shows that trust has positive effect on the intention of continuous use, and verifies the necessity of the antecedent factors (social presence, assurance, informativeness, economic feasibility, and seller reputation) for trust-building. This study provides strategy for the continuous growth of s-commerce, and suggests theoretical implication that explains the relationship between the characteristics of s-commerce and consumers.

• International Commerce and Information Review
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• v.10 no.1
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• pp.51-72
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• 2008

Recently, CRM has been integrated with e-CRM based on information and technology and its introduction is increasing. In particular, as a-CRM effectively collects information of customers with low cost and consolidates relations with customers through interactions with them, it is easier to achieve the marketing goals of companies. This study examines theories of CRM and a-CRM, and discusses development plan for successful introduction of e-CRM based on case studies on its introductions. Political suggestions are presented as follows: First, the basic rule to manage customers in respect to e-CRM is customer-oriented management. For optimal customer management, various customer service channels that support customers in real world as well as online should be provided for the best e-CRM system. Second, of increasing online customers, important customers should be sorted out for which individualized services should be provided and if so, they can be faithful customers. It is believed to be a true development direction of e-CRM appropriate to current society. With introduction of e-CRM, values and needs of customers should be analysed through various sorts of communication and information activities, and segmental marketing activities should be developed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.3
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• pp.792-812
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• 2022

Multi-agent systems often need to achieve the goal of learning more effectively for a task through coordination. Although the introduction of deep learning has addressed the state space problems, multi-agent learning remains infeasible because of the joint action spaces. Large-scale joint action spaces can be sparse according to implicit or explicit coordination structure, which can ensure reasonable coordination action through the coordination structure. In general, the multi-agent system is dynamic, which makes the relations among agents and the coordination structure are dynamic. Therefore, the explicit coordination structure can better represent the coordinative relationship among agents and achieve better coordination between agents. Inspired by the maximization of social group utility, we dynamically construct a factor graph as an explicit coordination structure to express the coordinative relationship according to the utility among agents and estimate the joint action values based on the local utility transfer among factor graphs. We present the application of such techniques in the scenario of multiple intelligent vehicle systems, where state space and action space are a problem and have too many interactions among agents. The results on the multiple intelligent vehicle systems demonstrate the efficiency and effectiveness of our proposed methods.