• Journal of Korea Water Resources Association
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• v.40 no.6 s.179
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• pp.431-446
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• 2007

Groundwater flow in a basin is greatly affected by many hydrogeological and hydrological characteristics of the basin. A groundwater flow model for the Kap-cheon basin ($area=648.3km^2$) in the Geum river basin was established using MODFLOW by fully considering major features obtained from observed data of 438 wells and 24 streams. Furthermore, spatial groundwater recharge distribution was estimated employing accurately calibrated watershed model developed using SWAT, a physically semi-distributed hydrological model. Model calibration using observed groundwater head data at 86 observation wells yielded the deterministic coefficient of 0.99 and the water budget discrepancy of 0.57%, indicating that the model well represented the regional groundwater flow in the Kap-cheon basin. Model simulation results showed that groundwater flow in the basin was strongly influenced by such factors as topological features, aquifer characteristics and streams. The streams in mountainous areas were found to alternate gaining and losing steams, while the streams in the vicinity of the mid-stream and down-stream, especially near the junction of Kap-cheon and Yudeong-cheon, areas were mostly appeared as gaining streams. Analysis of water budget showed that streams in mountainous areas except for the mid-stream and up-stream of Yudeong-cheon were mostly fed by groundwater recharge while the streams in the mid and down-stream areas were supplied from groundwater inflows from adjacent sub-basins. Hence, it was concluded that the interactions between surface water-groundwater in the Kap-cheon basin would be strongly inter-connected with not only streams but also groundwater flow system itself.

• Journal of Korea Water Resources Association
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• v.40 no.6 s.179
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• pp.459-468
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• 2007

To estimate the groundwater recharge, the fully distributed parameter based model, MIKE SHE was applied to the Gyeongan-cheon watershed which is one of the tributaries of Han River Basin, and covers approximately $260km^2$ with about 49 km main stream length. To set up the model, spatial data such as topography, land use, soil, and meteorological data were compiled, and grid size of 200m was applied considering computer ability and reliability of the results. The model was calibrated and validated using a split sample procedure against 4-year daily stream flows at the outlet of the watershed. Statistical criteria for the calibration and validation results indicated a good agreement between the simulated and observed stream flows. The annual recharges calculated from the model were compared with the values from the conventional groundwater recession curve method, and the simulated groundwater levels were compared with the observed values. As a result, it was concluded that the model could reasonably simulate the groundwater level and recharge, and could be a useful tool for estimating spatially/temporally the groundwater recharges, and enhancing the analysis of the watershed water cycle.

• Journal of Internet Computing and Services
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• v.6 no.4
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• pp.75-84
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• 2005

Grid computing enables a shift from a localized resource computing model to a fully-distributed virtual organization with shared resources, Accounting is one of the main obstacles to widespread adoption of the Grid. Accounting has until recently, been a sparsely-addressed problem, particularly in practice. In this paper, we design and implement the accounting information gathering system. Accounting information gathered at each local system does not include grid-aware information. To be useful in grid environment, grid user information must be included in accounting information. To make it useful in grid environment, we add grid user information with PGAM. Implemented system is based on OGSA, following GSAX framework of RUS-WG in GGF. And the schema of accounting information is following usage Record Fields of UR-WG in GGF. Also, the accounting information integrating and monitoring tool for system management in the Grid environment are implemented.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.1-10
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• 2013

The recent trend in the war fields on the globe may be characterized by the network-centric warfare, which would, in turn, make the concept of weapon systems be changed. To this end, the concept of system of systems (SoS) has been introduced in literature. An SoS is a collection of multiple systems, each of which is an independent system and can be interoperable with each other. Thus, in defense domain each SoS is a big weapon system as a whole operated in actual environment and each element of it is also an independent smaller weapon system, but they should be interoperable via network among each other. The safety results studied for each elementary system alone may not be fully applicable to the whole SoS. As such, the objective of this paper is to study how to make the SoS safety requirements be distributed down over the interoperable elementary systems. Since handling the interoperability requires a technique of systems architecture, a standard method called the DoD Architectural Framework (DoDAF) has been used here to derive a solution. Using DoDAF, the safety requirements were first analyzed in the operability environment. The results were then studied to be included in an integrated model of both the systems design and safety processes. A further study of present paper would facilitate ensuring safety in the development of SoS weapon systems in practice.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.10
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• pp.166-174
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• 1998

Neural networks, having highly nonlinear dynamics by virtue of the distributed nonlinearities and the learing ability, have the potential for the adaptive prediction of nonstationary signals. This paper describes the nonlinear prediction of these signals in two ways; using a nonlinear module and the cascade combination of nonlinear and linear modules. Fully-connected recurrent neural networks (RNNs) and a conventional tapped-delay-line (TDL) filter are used as the nonlinear and linear modules respectively. The dynamic behavior of the proposed predictors is demonstrated for chaotic time series adn speech signals. For the relative comparison of prediction performance, the proposed predictors are compared with a conventional ARMA linear prediction model. Experimental results show that the neural networks based adaptive predictor ourperforms the traditional linear scheme significantly. We also find that the cascade combination predictor is well suitable for the prediction of the time series which contain large variations of signal amplitude.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.329-333
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• 2021

V2G (Vehicle to Grid) technology for an EV (Electric Vehicle) has been assumed as so promising in a near future for its useful energy resource concept but still yet to be developed around the world for specific service purposes through various R&BD projects. Basically, V2G returns power stored in vehicle at a cheaper or unused time to the grid at more expensive or highly peaked time, and is accordingly supposed to provide such roles like peak shaving or load levelling according to customer load curve, frequency regulation or ancillary reserves, and balancing power fluctuation to grid from the weather-sensitive renewable sources like wind or solar generations. However, it has recently been debated over its prominent usage as diffusing EVs and the required charging/discharging infrastructure, partially for its addition of EV ownership costs with more frequent charging/discharging events and user inconvenience with a relative long-time participation in the previously engaged V2G program. This study suggests that a Korean DR (Demand Response) service integrated V2G system especially based upon a dynamic charge/pause/discharge scheme newly proposed to ISO/IEC 15118 rev. 2 can deal with these concerns with more profitable business model, while fully making up for the additional component (ex. battery) and service costs. It also indicates that the optimum economic, environmental, and grid impacts can be simulated for this V2G-DR service particularly designed for EV aggregators (V2G service providers) by proposing a specific V2G engagement program for the mediated DR service providers and the distributed EV owners.

• Proceedings of the Korea Database Society Conference
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• 1998.09a
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• pp.525-543
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• 1998

This paper proposes a conceptual taxonomy of architectures far workflow management systems. The systematic classification work is based on a framework for workflow architectures. The framework, consisting of generic-level, conceptual-level and implementation-level architectures, provides common architectural principles for designing a workflow management system. We define the taxonomy by considering the possibilities for centralization or distribution of data, control, and execution. That is, we take into account three criteria. How are the major components of a workflow model and system, like activities, roles, actors, and workcases, concretized in workflow architecture？ Which of the components is represented as software modules of the workflow architecture？ And how are they configured and operating in the architecture？ The workflow components might be embodied, as active (processes or threads) modules or as passive (data) modules, in the software architecture of a workflow management system. One or combinations of the components might become software modules in the software architecture. Finally, they might be centralized or distributed. The distribution of the components should be broken into three: Vertically, Horizontally and Fully distributed. Through the combination of these aspects, we can conceptually generate about 64 software Architectures for a workflow management system. That is, it should be possible to comprehend and characterize all kinds of software architectures for workflow management systems including the current existing systems as well as future systems. We believe that this taxonomy is a significant contribution because it adds clarity, completeness, and "global perspective" to workflow architectural discussions. The vocabulary suggested here includes workflow levels and aspects, allowing very different architectures to be discussed, compared, and contrasted. Added clarity is obtained because similar architectures from different vendors that used different terminology and techniques can now be seen to be identical at the higher level. Much of the complexity can be removed by thinking of workflow systems. Therefore, it is used to categorize existing workflow architectures and suggest a plethora of new workflow architectures. Finally, the taxonomy can be used for sorting out gems and stones amongst the architectures possibly generated. Thus, it might be a guideline not only for characterizing the existing workflow management systems, but also for solving the long-term and short-term architectural research issues, such as dynamic changes in workflow, transactional workflow, dynamically evolving workflow, large-scale workflow, etc., that have been proposed in the literature.

• The Journal of Information Technology and Database
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• v.5 no.1
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• pp.97-108
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• 1998

This paper proposes a conceptual taxonomy of architectures for workflow management systems. The systematic classification work is based on a framework for workflow architectures. The framework, consisting of generic-level, conceptual-level and implementation-level architectures, provides common architectural principles for designing a workflow management system. We define the taxonomy by considering the possibilities for centralization or distribution of data, control, and execution. That is, we take into account three criteria. How are the major components of a workflow model and system, like activities, roles, actors, and workcases, concretized in workflow architecture. Which of the components is represented as software modules of the workflow architecture\ulcorner And how are they configured and operating in the architecture\ulcorner The workflow components might be embodied, as active (processes or threads) modules or as passive (data) modules, in the software architecture of a workflow management system. One or combinations of the components might become software modules in the software architecture. Finally, they might be centralized or distributed. The distribution of the components should be broken into three: Vertically, Horizontally and Fully distributed. Through the combination of these aspects, we can conceptually generate about 64 software Architectures for a workflow management system. That is, it should be possible to comprehend and characterize all kinds of software architectures for workflow management systems including the current existing systems as well as future systems. We believe that this taxonomy is a significant contribution because it adds clarity, completeness, and global perspective to workflow architectural discussions. The vocabulary suggested here includes workflow levels and aspects, allowing very different architectures to be discussed, compared, and contrasted. Added clarity is obtained because similar architectures from different vendors that used different terminology and techniques can now be seen to be identical at the higher level. Much of the complexity can be removed by thinking of workflow systems. Therefore, it is used to categorize existing workflow architectures and suggest a plethora of new workflow architectures. Finally, the taxonomy can be used for sorting out gems and stones amongst the architectures possibly generated. Thus, it might be a guideline not only for characterizing the existing workflow management systems, but also for solving the long-term and short-term architectural research issues, such as dynamic changes in workflow, transactional workflow, dynamically evolving workflow, large-scale workflow, etc., that have been proposed in the literature.

• Journal of Distribution Science
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• v.13 no.7
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• pp.85-90
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• 2015

Purpose - Global trends play a part to change the structure of the fashion industry. In particular, companies attempting to conduct innovative marketing centering on such products as SPA brands are growing into global companies. SPA stands for "Specialty Store Retailer of Private Label Apparel", meaning its activities are fully integrated from manufacturing through sales, including material procurement design, product, distribution, inventory management, and final sales. For this reason, more understanding of individual corporate profitability is very sensitive to consumer's attitudinal changes. The effects that corporate marketing activities on customer lifetime value through brand attitude were analyzed based on a structural equation model. Rust suggested value equity, brand equity, and relationship equity as customer equity driver. The study examines Chinese consumer because China is the fastest growing fashion market in the world. Research design, data, and methodology - The survey targeted Chinese college student age 20s. Only respondents who had purchased SPA brands in the past year were included for this research. A total of 303, except for 47 missing data of 350 distributed questionnaires were included in this research. The questionnaire is consists of six part to measure value, brand, relationship equity, attitude toward brand, purchase intention and demographic characteristics. This research conducted exploratory factor analysis and reliability test. To verify research hypotheses, structural equation model test was conducted. As for customer equity, diversified models in consideration of the scope of acquisition data, a method of collection of data, influencing factor, and predictability were suggested based on a net present value model. However, the history of customer equity study is relatively short, and sufficient empirical analyses have not been conducted, so more integrated analysis is required. In this study, the concept of driver suggested by Rust was applied to figure out the effects that consumer's attitude has on customer equity. The customer equity driver suggested by them consists of brand equity, value equity, and relationship equity. Results - This study reveals that value equity and brand equity have a positive influence on relationship equity. And, relationship equity has a positive influence on purchase intention through brand attitude. However, value equity and brand equity do not influence on brand attitude. Conclusion - The results of this research generated following implications. First, SPA brands need to take advantage of their value equity such as perceived low price and up-to-date fashion style to attract Chinese young consumer. Second, strong brand equity promises dominants position in the competitive market. As Chinese fashion market grows rapidly, SPA brands can consider branding strategy such as flagship store and celebrity marketing enhancing brand image. Third, the core concept of customer equity strategy is to maintain a relationship with their expecting and existing customers. The relationship equity is built by brand equity and value equity. When SPA brands serves product and service meet with individual customers, customers have intimacy to the brands.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.5
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• pp.339-346
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• 2023

The uncertainties of microstructural features affect the properties of materials. Numerous pores that are randomly distributed in materials make it difficult to predict the properties of the materials. The distribution of pores in cementitious materials has a great influence on their mechanical properties. Existing studies focus on analyzing the statistical relationship between pore distribution and material responses, and the correlation between them is not yet fully determined. In this study, the mechanical response of cementitious materials is predicted through an image-based data approach using a convolutional neural network (CNN), and the correlation between pore distribution and material response is analyzed. The dataset for machine learning consists of high-resolution micro-CT images and the properties (tensile strength) of cementitious materials. The microstructures are characterized, and the mechanical properties are evaluated through 2D direct tension simulations using the phase-field fracture model. The attributes of input images are analyzed to identify the spot with the greatest influence on the prediction of material response through CNN. The correlation between pore distribution characteristics and material response is analyzed by comparing the active regions during the CNN process and the pore distribution.