• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.121-127
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• 2009

Wireless devices can communicate between each other without existing infrastructure in mobile Ad-hod network. Ad hoc networks can be used under difficult conditions, where it is difficult to construct infrastructures, such as shadowing areas, disaster areas, war area, and so on. In order to support to considerable and various wireless services, more spectrum resources are needed. However, efficient utilization of the frequency resource is difficult because of spectrum scarcity and the conventional frequency regulation. Ad-hoc networks employing cognitive radio (CR) system that guarantee high spectrum utilization provide effective way to increase the network capacity. In this paper, we simulate and compare the performance of conventional single and cooperative spectrum sensing with CR system using ad-hoc networks. And we demonstrate performance improvement by analyzing the system performance.

• Journal of the Korea Convergence Society
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• v.11 no.3
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• pp.227-235
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• 2020

This study found the following results through the comparative analysis of the history and development process of the Korean·U.S. women's soccer. First, the Korean women's soccer has a long history compared to U.S. soccer. However, the environmental factors such as the Korean war made the long years of gap. Second, to vitalize the women's soccer team in school, the legal and financial base are needed. School Sports Promotion Acts needs to be revised based on the Title IX in U.S. Third, in terms of professional soccer, many women's soccer players play abroad and are recognized. However, women's professional soccer players treatment is not enough compared to men's soccer. Therefore, corporate's financial support and the proper distribution of budget from the Korea football association are required.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.8
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• pp.976-984
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• 2012

Ad hoc networks can be used under difficult conditions, where it is difficult to construct infrastructures, such as shadowing areas, disaster areas, war area, and so on. In order to support to considerable and various wireless services, more spectrum resources are needed. However, efficient utilization of the frequency resource is difficult because of spectrum scarcity and the conventional frequency regulation. Ad-hoc networks employing cognitive radio(CR) system that guarantee high spectrum utilization provide effective way to increase the network capacity. However, there is a problem that all CR user do not fairly use the primary user's idle bandwidth which has been sensed. In this paper, to solve this problem, we propose the spectrum sharing algorithm which uses the multiple orthogonal sequences based on the code division multiple access(CDMA). From the proposed algorithm, it is expected that system performance of CR based ad-hoc network is improved significantly and it can be applied to the implementation of CR based ad-hoc network system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.5
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• pp.632-639
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• 2012

Ad-hoc networks can be used various environment, which it is difficult to construct infrastructures, such as shadowing areas, disaster areas, war area, and so on. In order to support to considerable and various wireless services, more spectrum resources are needed. However, efficient utilization of the frequency resource is difficult because of spectrum scarcity and the conventional frequency regulation. Ad-hoc networks employing cognitive radio(CR) system that guarantee high spectrum utilization provide effective way to increase the network capacity. In conventional CR based ad-hoc network, it uses constant threshold value to detect primary user signal, so the results become not reliable. In this paper, to solve this problem, we apply adaptive threshold value to the CR based ad-hoc network, and adaptive threshold is immediately changed by SNR(Signal to Noise Ratio). From the simulation results, we confirmed that proposed algorithm has the greatly better detection probabilities than conventional CR based ad-hoc network.

• Journal of Satellite, Information and Communications
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• v.6 no.2
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• pp.60-65
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• 2011

Wireless devices can communicate between each other without existing infrastructure in mobile Ad-hod network. Ad hoc networks can be used under difficult conditions, where it is difficult to construct infrastructures, such as shadowing areas, disaster areas, war area, and so on. In order to support to considerable and various wireless services, more spectrum resources are needed. However, efficient utilization of the frequency resource is difficult because of spectrum scarcity and the conventional frequency regulation. Ad-hoc networks employing cognitive radio (CR) system that guarantee high spectrum utilization provide effective way to increase the network capacity. In this paper, to improve detection performance of the energy detection which is widely used in CR based ad-hoc network, we propose multiple antenna system for CR based ad-hoc networks.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.409-409
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• 2019

개발도상국 중심의 전 세계인구 증가추세와 도시화 현상, 경제발전 등의 요인으로 자원 수요량이 꾸준히 증가하고 있으며 글로벌 자원전쟁 및 기후변화는 자원 확보 및 활용에 대한 불확실성을 가중시키고 있다. 특히 필수자원인 물, 에너지 그리고 식량은 서로 밀접한 연관성 (Interconnection)으로 인해 각 자원 간의 상호의존성(Interdependence), 상충관계(Trade-off), 시너지(Synergy)가 존재한다. 이를 인식하고 관련 데이터베이스를 구축하여 통합적인 관점에서 분석하는 것이 물-에너지-식량 넥서스(Water-Energy-Food Nexus, WEF Nexus)이다. 현재 해외에서는 WEF Nexus에 대한 정의를 정립하고 적용방안에 대한 연구가 활발히 진행 중이다. 하지만 국내 연구는 대부분 개념과 필요성 제시에 불과하며, 정량적인 방법들에 대한 분석은 부족한 실정이고, 다양한 적용방안에 대한 연구는 초기 단계에 불과하다. 이에 본 연구는 국내외 WEF Nexus에 대한 정량적 가치평가 연구들을 조사 분석하여, 국내 적용 시의 문제점 및 시사점을 제시하고자 한다. 국외에서도 전력, 양수발전, 소규모 수력발전, 원예, 도시농업 등 다양한 분야에서 WEF Nexus 접근방식을 통한 연구들이 진행되고 있으나 실제 구체적이고 명확한 방식에 의해 정량적 가치를 도출한 사례는 많지 않은 실정이다. 그러나 넥서스 접근방법의 긍정적 효과를 제시하기 위해서는 이와 같은 정량적 분석이 시급이 필요한 시점이다. WEF Nexus 접근법을 국내에 성공적으로 적용시키기 위해서는 (1) 자원별 데이터베이스 구축 (2) 다양한 다양한 평가 툴 개발 및 적용 (3) 자원간 통합적 접근 방안이 필요하다. 이러한 과정들 하나하나가 현실적이고 구체화하기 위해서는 아직까지 많은 시행착오가 필요할 것으로 보인다. 본 연구에서는 국제사회에서 제한적으로 적용된 다양한 정량화 방안들을 검토하고 국내 적용을 위해서 어떠한 사항들이 필요하고 구축되어야 하는지 제시하고자 한다.

• International Area Studies Review
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• v.15 no.2
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• pp.25-47
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• 2011

The paper will investigate the chances of progress in the peace process in Middle East. Robert Hazo's 1993 article mainly argued the Palestinians and Syrian problems. He saw that these two problems are one of the key issue that current Middle East problem which involves Israel. The key tenants of his argument will be dissected to assess whether this view holds true in the light of developments in the Middle East in the intervening years. The Arab-Israeli struggle remains one of the most intractable in history. In 1993 Robert Hazo concluded that 'the conflict is a terminal struggle'. This paper investigates his analysis in light of progress or lack of in the intervening period and against the contemporary strategic environment. It uses information presented in academic, government, newspaper and world wide web articles to conclude that Hazo's assessment remains valid. While the various talks since 1993 combined with the potential benefits the United States, Israel and Syria could gain from a settlement proffer hope, the issue of 'right of return, borders and Jerusalem are unlikely to be bridged in the near future.

• Convergence Security Journal
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• v.18 no.2
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• pp.133-139
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• 2018

The 5 Game changer means the concepts of the army's operation against the enemy's asymmetric threats so that minimize damage to the public and leads to victory in war in the shortest time. A study of network architecture of Dronebot operation is a key study to carry out integrated operation with integrated C4I system by organically linking several drones battle groups through ICT. The NBC reconnaissance drones can be used instead of vehicles and humans to detect NBC materials and share situations quickly. However, there is still a lack of research on the swarm flight of the NBC reconnaissance drones and the weaknesses of cyber electronic warfare. In this study, we present weaknesses and countermeasures of CBRNs in swarm flight operations and provide a basis for future research.

• Proceedings of the Korea Information Processing Society Conference
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• 2020.11a
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• pp.556-559
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• 2020

최근 태풍, 지진, 산불, 산사태, 전쟁 등 다양한 재난 상황으로 인한 인명피해와 자금 손실이 꾸준히 발생하고 있고 현재 이를 예방하고 복구하기 위해 많은 인력과 자금이 소요되고 있는 실정이다. 이러한 여러 재난 상황을 미리 감시하고 재난 발생의 빠른 인지 및 대처를 위해 본 논문에서는 인공지능 기반의 재난 드론 시스템을 설계 및 개발하였다. 본 연구에서는 사람이 감시하기 힘든 지역에 여러 대의 재난 드론을 이용하며 딥러닝 기반의 최단 경로 알고리즘을 적용해 각각의 드론이 최적의 경로로 효율적 탐색을 실시한다. 또한 드론의 근본적 문제인 배터리 용량 부족에 대한 문제점을 해결하기 위해 Ant Colony Optimization (ACO) 기술을 이용하여 각 드론의 최적 경로를 결정하게 된다. 제안한 시스템 구현을 위해 여러 재난 상황 중 산불 상황에 적용하였으며 전송된 데이터를 기반으로 산불지도를 만들고, 빔프로젝터를 탑재한 드론이 출동한 소방관에게 산불지도를 시각적으로 보여주었다. 제안한 시스템에서는 여러 대의 드론이 최적 경로 탐색 및 객체인식을 동시에 수행함으로써 빠른 시간 내에 재난 상황을 인지할 수 있다. 본 연구를 바탕으로 재난 드론 인프라를 구축하고 조난자 탐색(바다, 산, 밀림), 드론을 이용한 자체적인 화재진압, 방범 드론 등에 활용할 수 있다.

• Journal of Internet Computing and Services
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• v.25 no.1
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• pp.137-146
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• 2024

drones are used in a variety of fields, including business, leisure, lifesaving, and war. Various research using drones is being conducted in the military. In particular, the use of drones in 『Manned-Unmanned Complex combat performance plan』, powered by various unmanned vehicles deployed in the Army TIGER system, is expected to be a major factor realizing the Army's future combat performance that minimizes damage to ally combat troops while causing maximum damage to the enemy. As the deployment of various systems progresses, combat performance methods utilizing each system are evolving, but there is a lack of research to identify and resolve limitations in the perspective of unmanned vehicle operators. Based on the Ukrainian military's FPV drone combat case, we would like to make suggestions from the operator's perspective on overcoming perspective limitations through the introduction of FPV and the designation of military drone frequency.