• Korea Trade Review
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• v.44 no.1
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• pp.75-86
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• 2019

This study performs a factor analysis that affects the bunker oil price using the Co-integration model and Vector Error Correction Model (VECM). For this purpose, we use data from Clarkson and the analysis results show 17.6% decrease in bunker oil price when the amount of crude oil production increases at 1.0%, 10.3% increase in bunker oil price when the seaborne trade volume increases at 1.0%, 1.0% decrease in bunker oil price when total volume of vessels increases at 1.0%, and 0.003% increase in bunker oil price when 1.0% increase in world GDP, respectively. This study is meaningful in that this study estimates the speed of convergence to long-term equilibrium and identifies the price adjust mechanism which naturally exists in bunker oil market. And it is expected that the future study can provide statistically more meaningful econometric results if it can obtain data during more long-periods and use more various kinds of explanatory variables.

• Geotechnical Engineering
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• v.12 no.4
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• pp.145-156
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• 1996

An implicit stress integration algorithm was formulated for implementing an aiusotorpic hardening constitutive model which has been based op the generalized isotropic hardening rule in nonlinear finite element analysis technique. the rate form of stress tensor was implicitly integrated using the generalized trapezoidal rule and the tangent stress-strain modulus was evaluated consistently with the nonlinear solution technique. As a result, it has been found that the nonlinear analysis with the anisotropic hardening constitutive model might be performed accurately and efficiently.

• The Journal of Society for e-Business Studies
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• v.3 no.2
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• pp.141-160
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• 1998

In order to achieve a successful introduction of CALS, an enterprise model which is a concise description of what an enterprise does is required. The enterprise model mainly consists of a process model and a data model. The process model describes processes that create, change, combine, or destroy the entities within the enterprise. Several process modeling methodologies have been proposed. Each modeling methodology requires its own modeling view point, elements, and syntax. In developing a process model for CALS, these models created at different view points are required to analyze and design a system in a broad view. This paper aims at proposing an integration methodology for a process model. Specifically, IDEF0, IDEF3, and Petri Net are considered to be integrated. An IDEF0 model describing static functions of enterprise is transformed to an IDEF3 model describing behaviour of a system with additional information. Also, the IDEF3 model is transformed to a Petri Net model. These transformations will be automatically accomplished once the additional information for the transformation is provided.

• Atmosphere
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• v.33 no.4
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• pp.331-341
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• 2023

A numerical forecasting models usually predict future states by performing time integration considering fixed static time-steps. A time-step that is too long can cause model instability and failure of forecast simulation, and a time-step that is too short can cause unnecessary time integration calculations. Thus, in numerical models, the time-step size can be determined by the CFL (Courant-Friedrichs-Lewy)-condition, and this condition acts as a necessary condition for finding a numerical solution. A static time-step is defined as using the same fixed time-step for time integration. On the other hand, applying a different time-step for each integration while guaranteeing the stability of the solution in time advancement is called an adaptive time-step. The adaptive time-step algorithm is a method of presenting the maximum usable time-step suitable for each integration based on the CFL-condition for the adaptive time-step. In this paper, the adaptive time-step algorithm is applied for the Korean Integrated Model (KIM) to determine suitable parameters used for the adaptive time-step algorithm through the monthly verifications of 10-day simulations (during January and July 2017) at about 12 km resolution. By comparing the numerical results obtained by applying the 25 second static time-step to KIM in Supercomputer 5 (Nurion), it shows similar results in terms of forecast quality, presents the maximum available time-step for each integration, and improves the calculation efficiency by reducing the number of total time integrations by 19%.

• Journal of Korean Society of Rural Planning
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• v.15 no.2
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• pp.27-42
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• 2009

This study has intended to evaluate the subjective landscape of rural region using additive integration index calculation model in Seondong region, Gochang-gun, Jeollabuk-do, Korea. This study consists of the following three steps. First, this study defmed the rural landscape using survey and developed the estimating equation for rural landscape assessment index. Second, this study set up assessment units and assessment indicators, then estimated mean of representative landscape adjectives in accordance with them through residents-participatory evaluation. Third, this study calculated rural landscape assessment index using additive integration index calculation model, and evaluated subjective landscape of rural region in accordance with space types and landscape fields through mapping methodology. The results of this study can be described as follows: 1) satisfaction level for landscape in accordance with village (urban area and residential area) was very high; 2) satisfaction level was very high in both Ye-Jeon reservoir and Hakwon farm, representative landscape resources of the study area.

• Journal of Korean Society of Transportation
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• v.18 no.2
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• pp.7-16
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• 2000

This study Presents an guideline of the exclusive bus and/or truck lane on 8 lanes freeways using FREFLO model and INTEGRATiON model. Four alternatives : do nothing, bus exclusive lane, truck exclusive lane, bus and truck exclusive lane, were evaluated using average daily vehicle travel time as measures of effectiveness. It is found that bus and truck exclusive lane is the most effective alternative reducing total travel time by 7% when ADT is below 80,000 vehicle/day. However, when ADT is above 80,000 vehicle/day and bus Proportion is above 12%, bus exclusive lane is the most effective alternative reducing total travel time by more than 5.6%. It is further found that INTEGRATION, the stochastic and microscopic model, is more sensitive than FREFLO, the deterministic and macroscopic model, in evaluating the effectiveness of four alternatives.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2C
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• pp.333-341
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• 2004

Along with the innovative enhancement of Internet technology and the emergency of distributed systems extended from client-server computing, it becomes indispensible and necessary to integrate and interconnect old legacy systems. Since building a distributed system requires consistency of integration, the proper reuse of incumbent systems is critical to successful integration of current systems to distributed ones. CORBA(Common Object Request Broker Architecture) and object wrapping technique can provide middleware solutions that extend the applications of a legacy system with little modification to the application level while keeping client consistency of standard interface. By using these techniques for system integration it is easier and faster to extend services on application development to distributed environments. We propose a model on object wrapping system that can manage, integrate, and separate the functions delivered from CORBA. We apply the object wrapping model specifically to integration of security system interfaces and also perform a test to verify the usability and the efficiency of our model.

• Information Systems Review
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• v.11 no.2
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• pp.45-66
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• 2009

A number of companies are considering for merger and acquisition (M&A) as one of business strategies for their growth and survival. However, many of them do not create the synergy they had sought, and failed M&A, often result in negative outcomes in terms of productivity, market share, profitability and turnover of qualified employees. There have been numerous research studies conducted to analyze the factors that determine the success and failure of M&A, and it has been found that with the increasing dependence of many companies on information systems, post-M&A IS (information systems) integration success has a critical effect on the success of M&A. However, there have been very few studies on post-M&A IS integration success, and most have been restricted to integration of IS organizations or physical information systems. In order to conduct a comprehensive research on the factors that affect the success of post-M&A IS integration, this study surveyed preceding researches on not only information systems but also strategic management, economics, finance, HRM (human resource management) and organization management. Based on the findings, a comprehensive and integrated model of the influential factors on post-M&A IS integration has been proposed. The proposed model categorizes the factors into perspectives of M&A, strategy, organization, HRM and IS, and provides an empirical evaluation of each factor on the success of IS integration based on comparative case studies.

• Journal of ILASS-Korea
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• v.18 no.3
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• pp.132-139
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• 2013

Smoke emissions from light duty diesel vehicles were measured using light extinction method with the free acceleration test mode. The smoke emissions for each measurement cycle of the free acceleration method showed large variations according to driver's pedal pushing pattern. The smoke values for each measurement cycle initially increased and reach a peak value. Integration of the smoke emissions with time for each measurement cycle was performed to get a representative smoke value which was obtained by averaging the integrated results. Two kinds of integration time range were used. One is range over the whole measurement cycle of the free acceleration method. The other is only the acceleration range in the measurement cycle. Overall, variation of the representative smoke values obtained by the integration method was reduced comparing to the traditional representative smoke value which was obtained from a peak smoke value over the measurement cycle. Ten vehicles of the same model with 2.5 liter diesel engines, and seven vehicles of the same model with 2.7 liter diesel engines, were tested using the free acceleration test method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.1007-1014
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• 2003

It is important to integrate an enterprise application for automating of the business profess, which is responded by a flow of market environment. There are two categories of method that integrate enterprise applications. One is Synchronous Integration, and the other is Asynchronous Integration. EAI(Enterprise Application Integration) and Web service which of the asynchronous integration is focused in the automating method of the business process. After we construct the application integration for automating of the business process, we have to concern about managing of the business transaction. Many Organizations have proposed the process method of business transaction based on 2-phase commit protocol. But this method can′t supply the phase that classify the transaction by transaction weight. In this paper, we propose an efficient method of transaction process for business transactions, which is composed by ′Classify Phase′ that classify transactions. We called this model "3-Phase Commit Method Applied by Classify Phase", we design this model to manage an resource of enterprise efficiently. The proposed method is compared by the method based on 2-Phase commit that could be a problem of management the resource of enterprise, and the advantage of this method is certified to propose the solution of that problem.