• The Transactions of the Korea Information Processing Society
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• v.4 no.12
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• pp.2971-2984
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• 1997

In this paper, we propose an efficient video block Placement scheme that utilize the current disk product that has MZR disk characteristic and users' skewed access pattern on VOD. Also, we evaluate its performance through simulation and modeling of VOD server. The basic placement rule is to place on MZR disks by LP, SHP methods according to the Zipf distribution of popularity. To verify the proposed scheme, we examined its performance on workstation with 2 MZR disks under varied skewed factors. The proposed placement scheme showed better response time than the random method. To extend proposed placement scheme to disk group, we analyzed the theoretical maximum numbers of concurrent users and the required buffer size per user. For performance parameters for the proposed scheme, we considered the disk head scheduling methods, the placement methods and the striping unit. The result of experiments showed that the proposed scheme was effective.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2A
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• pp.119-127
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• 2006

In this two-part paper, we consider dynamic resource allocation in orthogonal frequency division multiple access(OFDMA). To reduce the reverse link overhead for channel quality information(CQI) feedback, a set of sub-carriers are tied up to a sub-channel to be used as the unit of CQI feedback, user-multiplexing and the corresponding power/rate allocation. Specifically, we focus on two sub-channel structures, either aggregated or distributed, where the SNR distribution over a sub-channel is modeled as Ricean in general, and the channel quality of a sub-channel is summarized as the mean and variance of channel gain envelop divided by noise standard deviation. Then, we develop a generalized two step channel/resource allocation algorithm, which uses the two statistical measurements, and analyze the spectral efficiency of the OFDMA system in terms of average frequency utilization. An extension to proportional fair algorithm will also be addressed. As confirmed by numerical results, the aggregated structure is preferred especially when intending aggressive link adaptation.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.3
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• pp.99-107
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• 2004

This study presents an application of GIS technologies to construct the graphic user interface for 3-dimensional exhibition of the results obtained by ocean hydrodynamic model. In coastal management studies, GIS provide a receptacle for scattered data from diverse sources and an improvement of the 3D visualization of such data. Within the frame of a GIS a variety of analytical, statistical and modeling tools can be applied to transform data and make them suitable for a given application. A 3D hydrodynamic model was driven by time-dependent external forcing such as tide, wind velocity, temperature. salinity, river discharge, and solar radiation under the open boundary condition. The Jinhae bay was selected as a case study. Here, we have used GeoMania v2.5 GIS software and its 3D Analyst extension module to visualize hydrodynamic model result that were simulated around the Jinhae bay.

• Journal of Digital Convergence
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• v.16 no.6
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• pp.143-150
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• 2018

This study used a learner acceptance model to investigate the effect of SNS characteristics on user satisfaction and visit intention. A structured self - report questionnaire was administered to 172 college students. Structural equation modeling was applied using SPSS 18.0 and AMOS 22.0. The results of this study are as follows: First of all, the usefulness of informativeness did not affect the usability of the extracted SNS characteristics, and the usability did not affect usability. (+) Influence of. The characteristics of SNS can be utilized as a marketing tool to increase customer 's use and influence the customer' s intention to visit and further to create customers. In the future, various age groups will have to be surveyed. By examining the correlation between the degree of food companies' involvement in SNS and consumer visits, one can see how SNS activities of restaurant companies affect marketing activities.

• 전자공학회논문지 IE
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• v.44 no.4
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• pp.11-18
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• 2007

Concept of URC does "with me wherever when, and the robot" which provides necessary service to me can be simply defined. This paper uses URC technology and various robots are implemented with a design. That is, we are going to implement that a user controls a virtual robot by communication between URC server with a design. We used an intelligent robot simulation tool, and a developer was easy, and it was intelligent, and we were connected to active URC server, and modeling did a system for simulation to be able to do an URC robot usefully. It was connected to an URC system and various robots and environments were composed with 3D, and, in this paper, a design and implementation did an intelligent robot simulation system so that it was possible by various contents development through simulation. The URC communication protocol and the URC server were based on a Planet v.1.2 ; Network Protocol, CAMUS(Context-Aware Middleware for URC Systems); URC Server, SAM(Service Agent Manager) v.1.2 ; Service API module developed in Electronics & Telecommunications Research Institute (ETRI).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.300-303
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• 2011

Owing to the improvement in CPU processing speed of Phones (hardware of smartphone), 3D engines loading, and expansion of the usable capacity, next-generation smartphone game markets are rising briskly. Therefore, in creating 3D game characters, realistic and free-form animations in a small screen of a smartphone are becoming important. Through this paper, as a method of creating characters and operating for game characters to cause user's feeling, with NURBS data of MAYA, We completed a face in turns of eyes, a nose, and a mouth, and with Polygon Cube tool, modeled hands and feet. After dividing a cube into half and modeling it, through mirror copying We completed the whole body and modeled the low-polygon. Then to model realistic and free-form characters, We completed each detail with ZBrush and applied Divide level up to 4. Though they might look rough and exaggerated, We tried to express stuck-out parts and fallen-in parts effectively and smoothly with Smooth brush effect, map and design the low-polygon 3D characters.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.4
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• pp.11-17
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• 2017

Organizations are experiencing an ever-growing concern of how to prevent confidential information leakage from internal employees. Those who have authorized access to organizational data are placed in a position of power that could well be abused and could cause significant damage to an organization. In this paper, we investigate the task of detecting such insider through a method of modeling a user's normal behavior in order to detect anomalies in that behavior which may be indicative of an data leakage. We make use of Hidden Markov Models to learn what constitutes normal behavior, and then use them to detect significant deviations from that behavior. Experiments have been made to determine the optimal HMM parameters and our result shows detection capability of 20% false positive and 80% detection rate.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.6
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• pp.307-315
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• 2003

This paper proposes a novel simulation method of WPGS (Wind Power Generation System). The rotation speed control method of turbine under variable wind speed using the pitch control is proposed. Moreover, when wind speed exceeds the cut-out wind speed, the turbine will be stopped by controlling pitch angle to 90$^{\circ}$, otherwise it will be controlled to steady-state operation. For the purpose of effective simulation, the SWRW (Simulation method for WPGS using Real Weather condition) is used for the utility interactive WPGS simulation in this paper, in which those of three topics for the WPGS simulation: user-friendly method, applicability to grid-connection and the utilization of the real weather conditions, are satisfied. It is impossible to consider the real weather conditions in the WPGS simulation using the EMTP type of simulators and PSPICE, etc. External parameter of the real weather conditions is necessary to ensure the simulation accuracy. The simulation of the WPGS using the real weather conditions including components modeling of wind turbine system is achieved by introducing the interface method of a non-linear external parameter and FORTRAN using PSCAD/EMTDC in this paper. The simulation of long-term, short-term, over cut-out and under cut-out wind speeds will be peformed by the proposed simulation method effectively. The efficiency of wind power generator, power converter and flow of energy are analyzed by wind speed of the long-term simulation. The generator output and current supplied into utility can be obtained by the short-term simulation. Finally, transient-state of the WPGS can be analyzed by the simulation results of over cut-out and under cut-out wind speeds, respectively.

• Journal of the Korea Fashion and Costume Design Association
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• v.14 no.2
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• pp.1-10
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• 2012

Clothing design is one of design products for human, the end user and corresponds to artifacts. Sometimes artifacts with one mono module exist, and so does artifacts assembled and combined with multi modules of same shape and size or various shapes and sizes and thus all design products can be understood by modularity concept. The purpose of this study was to make a new suggestion for the clothing design and production of high uniqueness and creativity by reviewing and synthesizing the foundation of clothing modularity concept as the original clothing design figures from the history have shown various modularity concept evolution from mono module to multi module stages. The methods of this study were to identify clothing modularity and analyze the type, evolving direction, and category of clothing modularity, and the value of clothing modularization design through comprehensive literature reviews on topic-related books and theses. The original clothing figures with Significance from the clothing history were analyzed in evolution sequence for application direction and value of clothing modularity in flat pattern. Clothing modularity in ancient clothing figures was classified as three types of the fixed, drapery, and straight lined in evolving direction from clothing of mono module to flat patterned clothing. The direction of clothing modularity was identified as mono- dual-triple-multi into another level of multi modularity after intentional devolution. The categorization of clothing modularity was identified in terms of clothing flat construction, clothing design construction, and clothing form modeling. The value of clothing modularization design using clothing modularity was identified as economical efficiency, convenience, promptitude, adaptability, functionality, and creativity.

• Fashion & Textile Research Journal
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• v.17 no.6
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• pp.932-941
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• 2015

An aging population and increasing consumer demand for high-quality and innovative new products are key drivers for growth in the cosmeceutical industry. Cosmeceuticals are defined as products with biologically active ingredients that have a measurable effect on the user. This study explored the effects of shopping orientation and store attributes on impulse buying behavior for cosmeceuticals. We obtained 437 usable questionnaires from university students who had purchased cosmeceutical products. Data analysis was conducted using confirmatory factor analysis and structural equation modeling analysis via AMOS 18.0. The findings were: 1) hedonic shopping orientation and convenience shopping orientation had positive effects on product efficacy and promotion of the cosmeceutical store 2) brand shopping orientation had a positive effects on store atmospheric, skin care service, and brand of the cosmeceuticals store and 3) product efficacy and promotion of store attributes had a direct effect on impulse buying behavior for cosmeceuticals. Consumers who tended to enjoy the shopping to refresh themselves and to experience convenient shopping were likely to purchase cosmeceuticals impulsively, which mediated by the store attributes (product efficacy and promotion). Therefore, we confirmed partly causal relationships among the shopping orientation, store attributes, and impulse buying behavior of cosmeceuticals. Both managerial and theoretical implication for practitioners and researchers were discussed for managing product information more efficiently along with promotion strategies to trigger cosmeceuticals consumers in the context of shopping.