• Journal of the Society of Naval Architects of Korea
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• v.51 no.4
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• pp.328-333
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• 2014

A hybrid particle-mesh method based on the vorticity-velocity formulation for solving the incompressible Navier-Stokes equations is a combination of the Vortex-In-Cell(VIC) method for convection and the penalization method for diffusion. The key feature of the numerical methods is to determine velocity and vorticity fields around a solid body on a temporary grid, and then the time evolution of the flow is computed by tracing the convection of each vortex element using the Lagrangian approach. Assuming that the vorticity and velocity fields are to be computed in time domain analysis, pressure fields are estimated through a complete set of solutions at present time step. It is possible to obtain vorticity and velocity fields prior to any pressure calculation since the pressure term is eliminated in the vorticity-velocity formulation. Therefore, pressure field is explicitly treated by solving a suitable Poisson equation. In this paper, we propose a simple way to numerically implement the vorticity-velocity-pressure formulation including a penalty term. For validation of the proposed numerical scheme, we illustrate the early development of viscous flows around an impulsive started circular cylinder for Reynolds number of 9500.

• Journal of Sport and Applied Science
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• v.4 no.3
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• pp.1-10
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• 2020

Purpose: This study is to explore which genre of sports culture contents will show the most consistent growth in the future and analyse the development outlook based on those results. Research design, data, and methodology: Case study was used for this research as it seemed to be the most appropriate approach in order to obtain the most complete and meaningful information from a particular phenomenon. A total of 15 participants were chosen to participate in a semi-structured in-depth interview and the recordings were typed out as text. In order to ensure validity and credibility of findings, peer and member check were conducted. Results: As a result, the sports culture content that is most likely to consistently grow in the future is games. Additionally, it is expected that sports culture contents will develop as new categories of sports culture contents emerge, as the evolution of sports culture content occurs through the combination with technology, as well as the activation of sensual sports contents, and the production of sports culture contents utilizing big data. Conclusions: It is concluded that convergence of sport, cultural contents, and technology will promptly progress, and it will promote the development of sport culture contents and related industry.

• Transactions on Control, Automation and Systems Engineering
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• v.3 no.2
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• pp.117-123
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• 2001

To improve control performance of a non-linear system, many other reserches have used the sliding model control algorithm. The sliding mode controller is known to be robust against nonlinear and unmodeled dynamic terms. However, this algorithm raises the inherent chattering caused by excessive switching inputs around the sliding surface. Therefore, in order to solve the chattering problem and improve control performance, this study has developed the sliding mode controller with a perturbation estimator using the observer-based fuzzy adaptive network. The perturbation estimator based on the fuzzy adaptive network generates the control input of compensating unmodeled dynamics terms and disturbance. And the weighting parameters of the fuzzy adaptive network are updated on-line by adaptive law in order to force the estimation errors converge to zero. Therefore, the combination of sliding mode control and fuzzy adaptive network gives rise to the robust and intelligent routine. For evaluation control performance of the proposed approach, tracking control simulation is carried is carried out for the hydraulic motion simulator which is a 6-degree of freedom parallel manipulator.

• Journal of Computational Design and Engineering
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• v.1 no.4
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• pp.256-265
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• 2014

Energy efficiency is an essential consideration in sustainable manufacturing. This study presents the car fender-based injection molding process optimization that aims to resolve the trade-off between energy consumption and product quality at the same time in which process parameters are optimized variables. The process is specially optimized by applying response surface methodology and using non-dominated sorting genetic algorithm II (NSGA II) in order to resolve multi-object optimization problems. To reduce computational cost and time in the problem-solving procedure, the combination of CAE-integration tools is employed. Based on the Pareto diagram, an appropriate solution is derived out to obtain optimal parameters. The optimization results show that the proposed approach can help effectively engineers in identifying optimal process parameters and achieving competitive advantages of energy consumption and product quality. In addition, the engineering analysis that can be employed to conduct holistic optimization of the injection molding process in order to increase energy efficiency and product quality was also mentioned in this paper.

• The Korean Journal of Ecology
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• v.25 no.1
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• pp.19-24
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• 2002

The traditional Japanese agricultural landscape, In which a set of varied land-use patches functions as a sustainable ecosystem landscape unit, not only provides the local people tilth a stable food supply, but also offers a variety of habitats to many species of wildlife. Therefore, remaining natural habitats including those in the traditional agricultural landscape should be maintained whenever possible. In addition, restoration work should be implemented in areas where the natural habitat has been destroyed or severely degraded by human activities. This basic approach to the natural environment is a combination of maintenance and restoration. Types of maintenance and restoration can be classified into three categories according to the countermeasures employed: preservation, conservation and protection types of maintenance, and improvement, reconstruction and creation types of restoration. Four steps are proposed for ecological restoration and maintenance of a target area: exploration, diagnosis, prescription and care. In this process, a model for approaching the goal is important. One of the most important models should center on the traditional agricultural landscape involving a sustainable farming ecosystem. It is necessary to protect traditional landscapes and ecosystems from the degrading impact of urbanization and industrialization, as well as to enhance efforts at restoration.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.17 no.1
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• pp.1-20
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• 2006

The family life cycle is a useful indicator of consumer behavior, as well as the family life cycle concept utilizes a combination of demographic and socioeconomic variables that best explains the changes in the construct of the family. The family decision-making research has frequently examined role relationship between husband and wife across stages and sub-decisions. The objective of this research is to measure children and parents' perceptions of the influence of the decision-making process for a family dining-out experience, and to determined the customers' choice behavior of restaurants according to isolated factors underlying the important attributes of the restaurants, and finally authors applied a market segmentation approach by capturing customers' preference of restaurant attributes in family dining-out situation and to investigated influence of the family decision making for family dining out in family life cycle. For practitioner, marketing implications are provided and recommendations for future research are also discussed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.6
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• pp.1304-1311
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• 2003

Target tracking in a real world situation is difficult problem because of continuous variations in images, huge amounts of data, and high processing speed demands. The problem becomes even harder in the case of sea background. This paper presents an initial study of neural network based method for target detection and tracking in cluttering environment. The approach uses a combination of differential motion analysis, Kohonen self-organizing network and region growing method. The network is capable of detecting the mass-centers of moving objects within one frame. The history of neurons positions in the sequential frames approximates the traces of the targets. The experiments done with the network in simulated environment showed promising results.

• Journal of Arbitration Studies
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• v.17 no.3
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• pp.145-167
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• 2007

Digital goods are defined as intangible and non-physical goods, composed of a combination of digital signals, electronically represented as 0 and 1. They are also called as digital products, electronic transmissions, information goods, digital contents, computer information, etc. Digital goods are now traded both domestically and internationally as well as on-line and off-line. Korean government revised the Basic Law on Foreign Trade to include digital goods and services as the scope of foreign trade in 2001. Trade volume of digital goods are increasing in Korea. The supply chains of digital goods from producing the components to selling globally to consumers are different from conventional physical goods. Mostly, digital goods are traded on the license basis rather than ownership contract. End User License Agreements(EULAs), such as shrink-wrap, click- wrap, or browser-wrap licenses are very popular in online transactions. Unlike conventional physical goods. the breach of license contract is closely linked with the infringement of intellectual property rights. Digitalized intellectual property is easy to copy and transmit in the cyber space. In cases of legal disputes from the breach of license contract, commercial arbitration or on-line alternative dispute resolutions(ADRs) are regarded as better approach to solve them rather than court sues. For promoting more secure and reliable international trade of digital goods. arbitration clauses should be included in most of license contracts.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.51 no.2
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• pp.60-67
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• 2002

This paper presents a control approach for designing a self tuning fuzzy controller for a synchronous generator excitation and SVC system. A combination of thyristor-controlled reactors and fixed capacitors (TCR-FC) type SVC is recognized as having the most flexible control and high speed response, which has been widely utilized in power systems, is considered and designed to improve the response of a synchronous generator, as well as controlling the system voltage. The proposed parameter self tuning algorithm of fuzzy controller is based on the steepest decent method using two direction vectors which make error between inference values of fuzzy controller and output values of the specially selected PSS reduce steepestly. Using input-output data pair obtained from PSS, the parameters in antecedent part and in consequent part of fuzzy inference rules are learned and tuned automatically using the proposed steepest decent method. The related simulation results show that the proposed fuzzy controller is more powerful than the conventional ones.

• Journal of Construction Engineering and Project Management
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• v.1 no.2
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• pp.11-17
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• 2011

Recent demands from construction industry have emphasized the capability for graduates to have improved skills both technical and non-technical such as problem solving, interpersonal communication. To satisfy these demands, problem-based learning that is an instructional method characterized by the use of real world problem has been adopted and has proven its effectiveness various disciplines. However, in spite of the importance of field senses and dealing with real problem, construction engineering education has generally focused on traditional lecture-oriented course. In order to improve limitations of current construction education and to satisfy recent demands from construction industry, this paper proposes a new educational approach that is Failure-Based Learning for using combination of the procedural characteristics of the problem-based learning theory in construction technology education utilizing failure information that has the educational value in the construction area by reinterpreting characteristics of construction industry and construction failure information. The major results of this study are summarized as follows. 1) Educational effect of problem-based learning methodology and limitation of application in construction area 2) The educational value of the information on construction failure and limitation in application of the information in construction sector 3) Anticipated effect from application of the failure-based learning 4) Development and application of the failure-based learning conceptual model.