• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.10
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• pp.53-59
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• 2004

A new downlink beamforming method is proposed for coherent detection of Cellular systems with BPSK modulation where there exists only common pilot channel. To solve phase mismatch between traffic and pilot signals at desired mobile and to reduce interference to other mobiles, the proposed downlink beamforming method considers a cost function of signal to interference ratio criteria and gives a solution for the cost function. The computer simulation showed that the proposed method can solve the phase mismatch problem and give improved BER performance in time-varying channels.

• Asia-Pacific Journal of Business
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• v.3 no.1
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• pp.10-16
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• 2012

India is having a high growth rate of Mobile subscribers which has opened up a new marketing channel of communication with customers. There is a need to study the factors affecting Mobile user's attitude towards Mobile marketing and the relationship between these factors. To study the mobile users attitude towards mobile marketing 489 mobile users opinion is taken on 12 statements for a period of 5 months. Using factor analysis method these 12 statements are grouped into 5 groups they are Mobile advertisement, Mobile Usability, Mobile Promotions, Mobiles shopping and Mobile Marketing. Confirmatory Factor Analysis (CFA) was performed to confirm the findings. SPSS Statistics 17.0 is used to conduct factor analysis and the validity of the model. Once the model was validated, SPSS Amos 18.0 was used to fit a model based on Structure Equation Model to analyze the factors affecting Mobile user's attitude and the relationship between these factors. The present study revealed that Mobile Advertisement and Mobile Sales Promotion are having positive effect on Mobile Marketing where as Mobile Shopping and Mobile Phone Usability is having negative effect on Mobile Marketing. The impact of indicators like Mobile Phone user's permission and personalization of Mobile Phone communication on Mobile Marketing are also discussed in this article.

• The Journal of Internal Korean Medicine
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• v.40 no.6
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• pp.1152-1168
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• 2019

Objectives: The aim of this study was to present several proposals for future pulse diagnosis practice and research by investigating the trend of pulse diagnosis studies in Korea. Methods: We searched online medical databases, including National Discovery for Science Leaders (NDSL), the Oriental Medicine Advanced Searching Integrated System (OASIS), the Research Information Sharing Service (RISS), and the Korean Traditional Knowledge Portal (KTKP), for pulse diagnosis articles in Korea. We selected articles on pulse diagnosis but excluded duplicate articles, articles irrelevant to pulse diagnosis, and articles published in foreign countries. Results: In the first screening, 801 articles were selected. We found 251 articles and classified them according to category. The medical engineering field had 148 articles. A total of 24 articles were related to algorithms for pulse wave detection, 34 to sensors, five to pressurization technology, 16 to systems, 11 to remote medical service, five to mobiles, nine to trends, and 44 to basic research. The Korean medicine field had 103 articles. A total of 41 articles were devoted to literature reviews, 20 to case reports, 11 to constitutional medicine, six to experimental studies, and 25 to relevant research. Conclusion: More efforts to practice pulse diagnosis for various diseases should be made and the results actively published.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.5
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• pp.197-203
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• 2008

In this work, we present a novel genetic approach to solve the problem of combining power control and data rate transmission adjustment for the performance enhancement of the next generation CDMA system. We obtained the optimal solution of multi rate and power control problem by compromising slightly on SIR limit values. The proposed algorithm was able to handle many more users with comparable or faster convergent service. While this paper considered two kinds of fitness function such as maximizing the total transmission data rate and maximizing the acceptable mobiles of CDMA cellular network, the evaluation function combining these two cases or others can be also easily implemented. The simulation results showed the effectiveness and validity of our approach.

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.477-486
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• 2011

The purpose of this paper was to examine the teaching and learning activities using mobiles devices in a university. We analyzed the instructional methods, instructional strategies, devices types, and evaluation activities. In addition, we conducted deep interviews with the students who used the mobile devices in terms of their understanding on the mobile learning, mobile learning methods, evaluation methods, difficulties and their expectations. These findings will be used to improve the quality of the teaching and learning methods using mobile devices in higher education.

• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.792-801
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• 2010

In this paper, we introduce a novel scene graph library for mobile platforms, called the 'Mobile OpenSceneGraph (Mobile OSG)', as a mobile graphics middleware. Our mobile scene graph library supports several nice properties, including platform-independence, extensibility, touch-based UI supports, and compatibility, by carefully adapting the OpenSceneGraph library, one of the most widely used graphics middlewares for desktop platforms, to mobile platforms. We validate the usefulness of the proposed library for mobiles with the several experimental results including real-time rendering, camera manipulations with a touch-based UI, and animations with switching geometric nodes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.611-614
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• 2012

Space-Time Block Code (STBC) is a simple transmit diversity scheme mitigating detrimental effects of fading channel. However, STBC receivers require channel knowledge and suffer from inaccurate channel estimation. Differential Space-Time Modulation (DSTM) renders the receiver a choice of coherent detection or non-coherent detection, depending on the availability of the channel information. Based on the simulated BER performances of these two schemes over various normalized Doppler frequency scenarios using LTE-like parameters, a benefit of adaptively switching the receiver type is investigated.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.6C
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• pp.551-559
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• 2005

Estimation of unknown signal parameters with sensor array measurements has been investigated quite extensively. Also, there has been in recent years an explosive increase in the number of mobile users in wireless cellular systems, thus contributing to growing levels of multi-user interference. To overcome this problem, application of adaptive antenna array techniques to further increase the channel capacity has been discussed. In this paper, a new model of locally scattered signals in the vicinity of mobiles is proposed by defining the mean steering vector and is manipulated mathematically for several distributions. Under this model an estimation method of the angle of arrival(AOA) is investigated based on a weighted subspace fitting(WSF) technique. Statistical analysis and simulations are also considered.

• Convergence Security Journal
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• v.10 no.1
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• pp.1-8
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• 2010

Recently, the number of internet users using smartphone is increasing worldwide, and the interest in the smartphone malware is increasing. Especially, since mobile malware are occurring to the smartphones using Symbian or Windows Mobiles in the abroad, it is necessary to have an action plan against these mal wares. This paper describes the possible security threat through the analysis of the mal wares occurred after 2004. Also we present a model for the future propagation prevention system which can cope with domestic smartphone mal wares.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.5
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• pp.443-449
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• 2014

This study aims to develop a Flywheel Energy Storage System (FESS) that uses wind power produced when an urban train is in motion, by utilizing a mounted turbine. This system was designed to generate and store electric power from wind power of a travelling urban train. The flywheel was designed to continue rotation using a one-way clutch bearing installed in the turbine shaft pulley, even in cases where the urban train decelerates or stops. This FESS can generate an additional 44% of electric power in comparison to a system not equipped with a flywheel. The generated power and operational features of the FESS were evaluated and verified through a wind tunnel test. The results show that the electric power stored in the FESS could supply auxiliary power for urban train components or service equipment, such as charging mobiles, Wi-Fi modules, and electric lights.