• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.418-423
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• 2019

The purpose of this study was to determine how the different number of channels of coils were related in the perceived signal intensity under identical parameters and area. Dedicated knee phantoms were scanned consecutively using both of the 16-channel and 8-channel knee coils. The T1 weighted and T2 weighted sequences were acquired using both coils to compare the signal intensities according to the number of channels. As a result, the 16-channel knee coils outperformed the 8-channel knee coils and the signal intensity was significantly increased in both of the T1 and T2 weighted images with the 16-channel coil. In conclusion, it is considered that better signal intensities and more clinical utility can be provided, when coils with more number of channels are used rather than using the coils with smaller number of channels.

• Journal of Advanced Navigation Technology
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• v.10 no.4
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• pp.394-399
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• 2006

In this paper, we investigated performance for 5.8GHz dedicated short range communication system using OFDM which will be applied to Intelligent transportation system services. The maximum speed of a vehicle in DSRC channel is very fast as 180km/h, so a service time is very short to serve a various traffic information if hand-off is not occurred. Therefore higher bit rate is required to proved advanced and intelligent service to the drivers of various vehicle and the data transmission rate of the next generation DSRC system if being promoted over 10Mbps. The signals received in Clarke & Gans channel have been simulated using the computer simulator.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.5B
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• pp.317-323
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• 2005

Broadcast disks are suited for disseminating information to a large number of clients in mobile computing environments. In broadcast disks, the server continuously and repeatedly broadcasts all data items in the database to clients without specific requests. The clients monitor the broadcast channel and retrieve data items as they arrive on the broadcast channel. The broadcast channel then becomes a disk from which clients can retrieve data items. This paper proposes a Timestamp based Concurrency Control (TCC) scheme to preserve the consistency of read-only client transactions, when the values of broadcast data items are updated at the server. Previous schemes tried to reduce transaction aborts by consuming considerable amount of downlink communication from the server to clients for transferring control information. On the other hand, the TCC uses a timestamp field of each data item to describe execution order of server transactions. Clients can allow more transaction executions by checking consistency of their read-only transactions with timestamps of data items. As a result, the TCC can reduce the abort ratio of client transactions with minimal control information to be broadcast from the server.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.92-95
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• 2000

본 논문에서 항만 자동게이트통관시스템에 사용하기 위하여 단거리전용통신(DSRC)용 OBE에 사용되는 5.8㎓ 송신기 MMIC를 설계하였다. 능동소자로는 GaAs MESFET을 사용하였고, 회로의 복잡도를 줄이기 위해 직접변조방식을 채택하였다. 인접채널간섭의 영향을 줄이기 위하여 드레인 재어 변조회로를 사용하여 -40dBc이하의 인접채널간섭과 70dB 이상의 on/off비를 갖는 5.8㎓ ASK송신기 회로를 설계하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2014.11a
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• pp.294-297
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• 2014

리테일 업계의 최대 화두는 다양한 미디어 채널을 상호 연계하여 방문고객체험을 극대화시키는 것이다. 리테일 매장을 방문하는 고객들은 이미 스마트폰을 사용하여 관심상품을 미리 조회해보고, 상품평도 살펴본다. 본 논문에서는 리테일 매장 내 게임체험 전용공간을 마련하고 방문고객의 게임 앱 사용행태를 분석한다. 이를 바탕으로 리테일 매장을 게임 홍보채널로 활용하고자 하는 욕구를 가지는 게임 스타트업 업체에게 사용자 체험 극대화를 위한 제안 및 분석자료를 마련한다.

• The Journal of the Korea Contents Association
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• v.20 no.9
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• pp.169-186
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• 2020

This study aims to examine the characteristics of news content and users' reactions in local broadcasting Youtube news' channel, and explore how the local media should response in the new online video environment. YouTube Open API sampled 3,950 news-related videos uploaded over a month on 31 YouTube news channels nationwide. The content analysis was performed on the basis of the analysis of individual videos, such as characteristics of each content and users' reactions. As a result, a few news channels have produced digital-only content, but the ratio has been very low, most were broadcast replay videos with titles and formats uploaded as they were. In some cases, it still operates as a comprehensive channel, which failed to show its expertise as an independent digital news platform. This shows that theses YouTube channels lacks differentiation from TV or its own web page, and is still skewed to the auxiliary role or online archive function of TV platform. Nevertheless, digital-only content, which can be a national issue based on regional expertise, has led to a higher number of views and users reactions, suggesting that is a realistic and effective strategy with expandability in online space in the future.

• Journal of KIISE:Information Networking
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• v.34 no.5
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• pp.396-404
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• 2007

In this paper, an Ad-hoc Routing Protocol which works in wireless Ad-hoc communication networks with multiple radios and multiple channels, and controls call admission based on bandwidth measurement is proposed. Unlike the conventional Ad-hoc node with a single radio using a single channel, an Ad-hoc node of the protocol proposed, MCQosR(Multiple Channel Quality of Service Routing), has multiple radios and uses multiple channels, which makes full duplex transmission between wireless Ad-hoc nodes, and reduces the intra interference on a route. Also, a fixed channel only for reception at each node enables the measurement of the available bandwidth, which is used to control the call admission for QoS provision. The performance of MCQosR is verified by simulation.

• Journal of Advanced Navigation Technology
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• v.10 no.1
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• pp.7-12
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• 2006

In this paper, we investigated performance for 5.8GHz dedicated short range communication system using OFDM which will be applied to Intelligent transportation system services. The maximum speed of a vehicle in DSRC channel is very fast as 180km/h, so a service time is very short to serve a various traffic information if hand-off is not occurred. Therefore higher bit rate is required to proved advanced and intelligent service to the drivers of various vehicle and the data transmission rate of the next generation DSRC system if being promoted over 10Mbps. The signals received in Racian channel have been simulated using the computer simulator. For performance improvement, BCH coding scheme are adopted.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.10A
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• pp.1453-1461
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• 1999

In this paper, we propose a new scheme that improve the performance of the conventional link access scheme in DSRC MAC and evaluate the performance of the proposed scheme. By using carrier sensing mechanism in random access channels, the proposed scheme can reduce the probability that the collisions among the link access traffics with different priorities may occur in random access channels, and provide differentiated link access delays according to the priorities. Furthermore, the proposed scheme can improve the performance of link access by using modified reservation mode. According to simulation results, it is shown that the proposed scheme is better than conventional method in view of the mean access delay and throughput in random access channels.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.3B
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• pp.226-236
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• 2002

In this paper, we present the channel assignment and management methods for an efficient use of traffic channel resource for supporting 12.2 Kbps, 64 Kbps, and 384 Kbps traffic with the different quality of service (QoS) in the radio network controller (RNC) in asynchronous IMT-2000 system. We first describe two types of traffic channel block assignments for utilizing the traffic channel efficiently; the partially dedicated and partially shared channel (PDPSC) assignment and the completely shared channel (CSC) assignment. The former is that some traffic channel block is completely assigned to each traffic type and the other blocks are shared with some traffic type. The latter is that all traffic channel blocks are completely shared with all traffic types. Further, for efficiently assigning, releasing, and managing the channel resource, we present the traffic channel management method which consists of the block and task management step. Through numerical examples, we evaluate the blocking probability and the mean number of required search for fading the available channel when applying our proposed channel block assignment and resource management methods.