• Electronics and Telecommunications Trends
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• v.30 no.2
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• pp.115-124
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• 2015

본고는 2010년에 이어 두 번째로 대규모 멀티밴드 동시경매를 시행하려고 준비해온 독일의 경매 계획 추진과정과 정책동향에 대하여 분석 정리하였다. 본고의 독일 사례 분석결과에 따르면, 대규모 멀티밴드 동시경매는 장점이 많기 때문에 국내의 경우에도 특히 저대역(700MHz 포함)과 고대역 간 밴드 시너지를 높일 수 있는 멀티밴드 동시경매를 정책화하는 것이 효율적인 주파수 활용을 위해 타당할 것이다.

• Electronics and Telecommunications Trends
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• v.27 no.6
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• pp.94-103
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• 2012

스마트폰, 태블릿 PC 등 정보 기술의 급속한 확대로 주파수 수요가 증가하여 세계 각국은 모바일 데이터 트래픽 수용을 위한 주파수 확보에 노력하고 있다. 미국은 원활한 주파수 확보를 통한 초고속 광대역 통신망의 확충이 통신 분야에서 미래 국제 경쟁력 확보에 필수적이라는 것을 인식하고, 새로운 대역에서 모바일 주파수를 확보하는 노력뿐 아니라 기존 대역에서 1차 사용자를 보호하며 공유할 수 있는 공유 주파수 자원의 확보도 추진하고 있다. 주파수 공유를 도입하면 필요한 주파수를 짧은 기간에 경제적인 가격으로 확보 가능하다는 장점이 있다. 본고는 미국에서 주파수 공유를 위해 도입하는 최근의 스펙트럼 정책 동향에 대해 기술하고자 한다.

• Asia Pacific Journal of Business Review
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• v.1 no.2
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• pp.63-88
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• 2017

With the advent of new frontiers in robotics, the spectrum of robot research area has widened in many fields and applications. Other than conventional robot research, many technologies such as smart devices, drones, healthcare robots, and soft robots are emerging as promising applications. Due to the research complexity of this topic, this research requires international collaboration and should be fertilized by R&D policies. This paper aims to propose a method to perform a cross-national analysis of robot research with unstructured data such as papers in the proceedings of an international conference. Text analytics are applied to extract research issues and applications in an automatic manner.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.10
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• pp.914-923
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• 2015

UAS(Unmanned Aircraft System) has been used a lot in military applications but recently its usage is expanding to commercial applications due to its recent technical development and its market is expected to grow rapidly in the future. In hyper-connectivity society, especially UAS would play major role as an one of potential infrastructures for the architecture of the next 5G system. The ultimate goal is the successful integration of UAS in NAS(National Airspace System) relies heavily on ensuring reliable spectrum for the robust CNPC(Command and Non-Payload Communication) links as well as payload links for other various applications in the upcoming hyper-connectivity era. In this paper, we have focused on the analysis of the existing frequencies for UAS radio-control and the current issues for CNPC and payload frequencies, and proposed future efficient utilization policy for UAS in the hyper-connectivity society.

• Health Policy and Management
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• v.25 no.4
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• pp.323-332
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• 2015

Background: Antibiotic resistance has been becoming serious challenge to human beings. Overuse of antibiotics, especially, for infants is concerned, but studies are very few for the prescribing pattern of antibiotic use for infants. This study analyzes prescribing patterns of antibiotics in outpatients of preschool children with acute respiratory tract infections in South Korea. Methods: Data are used from 2011 Health Insurance Review & Assessment Services-pediatric patients sample. Inclusion criteria is outpatient children (0 to 5 years) with top five frequent diseases. Prescription rates are analyzed by types of disease, provider, specialty, region, and ages. Binary or multinomial logit models are used to analyze determinants of providers' prescription pattern. Results: The main findings are as follows. First, distributions of prescription rates are shown as L-shape or M-shape depending on the types of disease. Second, the prescription variation is so large among providers, where providers are polarized as a group with low prescription rates and the other group with high prescription rates, though the shapes are shown diversified across types of disease. Third, prescription rates appear to be lower in pediatrics and higher in ENT (ear-nose-throat). Fourth, broad spectrum antibiotics are widely used among children. Finally, the logit analysis shows similar results with descriptive statistics, but partly different results across types of disease. Conclusion: Antibiotics for respiratory tract infections of infants are used excessively with a large variation among providers, and especially broad spectrum antibiotics are used. The prescription guideline for antibiotics should be provided for each specific disease to reduce antibiotic resistance in the future.

• Journal of Communications and Networks
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• v.10 no.3
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• pp.287-296
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• 2008

The IEEE 802.11 wireless standard uses the carrier sense multiple access with collision avoidance (CSMA/CA) as its MAC protocol (during the distributed coordination function period). This protocol is an adaptation of the CSMA/CD of the wired networks. CSMA/CA mechanism cannot guarantee quality of service (QoS) required by the application because orits random access method. In this study, we propose a new MAC protocol that considers different types of traffic (e.g., voice and data) and for each traffic type different priority levels are assigned. To improve the QoS of IEEE 802.11 MAC protocols over a multi-channel CSMA/CA, we have developed a new admission policy for both voice and data traffics. This protocol can be performed in direct sequence spread spectrum (DSSS) or frequency hopping spread spectrum (FHSS). For voice traffic we reserve a channel, while for data traffic the access is random using a CSMA/CA mechanism, and in this case a selective reject and push-out mechanism is added to meet the quality of service required by data traffic. To study the performance of the proposed protocol and to show the benefits of our design, a mathematical model is built based on Markov chains. The system could be represented by a Markov chain which is difficult to solve as the state-space is too large. This is due to the resource management and user mobility. Thus, we propose to build an aggregated Markov chain with a smaller state-space that allows performance measures to be computed easily. We have used stochastic comparisons of Markov chains to prove that the proposed access protocol (with selective reject and push-out mechanisms) gives less loss rates of high priority connections (data and voices) than the traditional one (without admission policy and selective reject and push-out mechanisms). We give numerical results to confirm mathematical proofs.

• The Journal of Sustainable Design and Educational Environment Research
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• v.22 no.3
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• pp.1-13
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• 2023

This study aims to analyze related laws and institutions and identify research trends and the policy implementation status of the multifunctionalization of school facilities. Beginning in 2001 at Seoul Geumho Elementary School, the enactment of the "Act On The Establishment, Operation And Management Of Multifunction School Facilities" in 2020, was elucidated through the concept and spectrum of the multifunctionalization of school facilities. The relevant research mainly focuses on elementary schools, elderly facilities, and space planning. The Living SOC Project in 2019 acted as a trigger in promoting the multifunctionalization of school facilities as a central government policy. In 2023, the Ministry of Education announced measures and guidelines for establishing the multifunctionalization of school facilities by conducting the project with respect to the "Nulbum School" policy.

• International Journal of Internet, Broadcasting and Communication
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• v.10 no.3
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• pp.59-64
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• 2018

A cooperative spectrum sensing has been proposed to improve the sensing performance in cognitive radio (CR) network. However, cooperative sensing causes additional overhead for reporting the result of local sensing to the fusion center. In this paper, we propose a technique to reduce the overhead of data transmission of cooperative sensing for applying the quantum data fusion technique in cognitive radio networks by omitting the lowest quantized in the local sensed results. If a CR node senses the lowest quantized level, it will not send its local sensing data in the corresponding sensing period. The fusion center can implcitly know that a spectific CR node sensed lowest level if there is no report from that CR node. The goal of proposed sensing policy is to reduce the overhead of quantized data fusion scheme for cooperative sensing. Also, our scheme can be adapted to all quantized data fusion schemes because it only deal with the form of the quantized data report. The experimental results show that the proposed scheme improves performance in terms of reporting overhead.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.401-403
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• 2013

Myopic method which is one of dynamic spectrum access method is an advantage that it maximizes immediate throughput is not complicated, and the simple and effective. The disadvantage of myopic method is that there may become less efficient because of conflicts between users secondary secondary user becomes many. Between the secondary if the secondary all users, select a channel to maximize the throughput of their own without considering the secondary other users, but it will try transfer secondary most users select the same channel collision will be more. Myopic / CA method has been proposed to solve this problem. Instead of selecting one channel to maximize their performance, select a candidate channels plurality of their advantage, the secondary user transfers to randomly selected channel that one in this way is a scheme. In this paper, we analyze whether it can be defined in a number of the channel number of candidates, depending on the network environment, maximizes the performance of the entire network.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.247-254
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• 2021

Problems such as a limited frequency resource and interference between adjacent bands have been continuously raised because of rapidly developing wireless technology and communication service. In order to solve that problem, government has been developed and operating the Spectrum Management Intelligent System(SMIS). This paper compares the results simulated by SMIS with the ATDI and the Matlab coded provided by ITU-R for verification of SMIS operating for the public interests. The Recommendation ITU-R P.526, P.1546, and P.1812 among the propagation model loaded in SMIS were chosen because of the relation to the broadcasting service. The comparison and analysis result shows that the outputs derived by SMIS has the small error of less than 1 dB. This research could be utilized for the policy establishment and R&D for the frequency allocation and the interference between adjacent bands.