• 한국콘텐츠학회논문지
• /
• 제8권10호
• /
• pp.381-390
• /
• 2008

컴퓨터 기술이 발달하고 많은 교육 방법들이 나타나면서 웹에 기반한 협동학습과 교육용 게임이 많은 관심을 받고 있다. 몇몇 협동학습 시스템들과 게임 기반 교육 시스템이 제안되었지만 게임을 이용한 협동학습 시스템에 대한 연구는 거의 없었다. 본 논문에서는 학습자들의 능동적인 참여와 흥미를 유발할 수 있는 게임을 이용한 웹기반 협동학습 시스템을 개발하였다. 협동학습은 각 조별로 이루어지며 다른 조와는 게임을 통해 경쟁하게 하였고, 게임은 누구나 쉽게 익힐 수 있고 협동학습 시나리오에 적합한 가로세로 퍼즐게임을 사용하였다. 제안 시스템의 유용성을 증명하기위해 실제 두 반의 고등학생들에게 적용하는 실험을 하였으며 그 결과 제안 시스템을 사용한 교육이 학업성취도나 흥미도 등에서 유의미한 결과를 보임을 보였다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제6권10호
• /
• pp.2455-2472
• /
• 2012

Although underlay spectrum sharing has been shown as a promising technique to promote the spectrum utilization in cognitive radio networks (CRNs), it may suffer bad secondary performance due to the strict power constraints imposed at secondary systems and the interference from primary systems. In this paper, we propose a two-phase based cooperative transmission protocol with the interference cancellation (IC) and best-relay selection to improve the secondary performance in underlay models under stringent power constraints while ensuring the primary quality-of-service (QoS). In the proposed protocol, IC is employed at both the secondary relays and the secondary destination, where the IC-based best-relay selection and cooperative relaying schemes are well developed to reduce the interference from primary systems. The closed-form expression of secondary outage probability is derived for the proposed protocol over Rayleigh fading channels. Simulation results show that, with a guaranteed primary outage probability, the proposed protocol can achieve not only lower secondary outage probability but also higher secondary diversity order than the traditional underlay case.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제2권3호
• /
• pp.185-190
• /
• 2002

In distributed autonomous robotic systems (DARS), each robot must behave by itself according to its states ad environments, and if necessary, must cooperate with other robots in order to carry out their given tasks. Its most significant merit is that they determine their behavior independently, and cooperate with other robots in order to perform the given tasks. Especially, in DARS, it is essential for each robot to have evolution ability in order to increase the performance of system. In this paper, a schema co-evolutionary algorithm is proposed for the evolution of collective autonomous mobile robots. Each robot exchanges the information, chromosome used in this algorithm, through communication with other robots. Each robot diffuses its chromosome to two or more robots, receives other robot's chromosome and creates new species. Therefore if one robot receives another robot's chromosome, the robot creates new chromosome. We verify the effectiveness of the proposed algorithm by applying it to cooperative search problem.

• 한국자동차공학회논문집
• /
• 제12권4호
• /
• pp.129-138
• /
• 2004

In this paper, we propose a method to apply a decentralized control algorithm for passive velocity field control using virtual flywheel system to cooperative 3-wheeled mobile robots, and these subsystem are under nonholonomic constraints. The considered robotic systems convey a common rigid object in a horizontal plain. Moreover we will proof the passivity and robustness for cooperative mobile robotic systems with decentralized passive velocity field control. Finally, The effectiveness of proposed control algorithm is examined by numerical simulation for cooperation tasks with 3-wheeled mobile robot systems.

• 한국정보처리학회논문지
• /
• 제6권5호
• /
• pp.1253-1262
• /
• 1999

For the efficient co-authoring of multimedia documents in a distributed systems environment, the cooperative-work management systems that can not only allow the sharing of distributed resources but also facilitate the authors' interaction, are needed. In this paper, we present a cooperative-work management system with hybrid architecture, called CW-MAN, in which the information on shared objects and co-authoring management is stored in a dedicated computer system but the shared objects distributed all over the local computer systems. The main management functions provided by the CW-MAN are those for shared objects, session, and telepointing. The shared-object use them exclusively. The session managements allows authors to dynamically create, update, and destroy sessions. Lastly, the telepointing management allows local pointing events to be synchronously presented to remote systems.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제18권6호
• /
• pp.1431-1448
• /
• 2024

Complexity science is a new stage in the development of systems science that is the frontier areas of contemporary scientific development. Complexity science takes complex systems as the research object, which has attracted widespread attention from researchers in the fields of economy, control, management, and society. In recent years, with the rapid development of science and technology and people's deepening understanding for the theory of complex systems, the systems are no longer an object with a single function, but the systems are composed of multiple individuals with autonomous capabilities through cooperative and cooperation, namely multi-agent system (MAS). Currently, MAS is one of the main models for studying such complex systems. The intelligent control is to break the traditional multi-agent fault-tolerant control (FTC) concept and produce a new type of compensation mechanism. In this paper, the applications of fault-tolerant control methods for MASs are presented, and a discussion is given about development and challenges in this field.

• 한국ITS학회 논문지
• /
• 제17권2호
• /
• pp.128-141
• /
• 2018

본 논문에서는 대표적인 6대 협력형 차량 안전 시스템 대한 잠재적인 사회적 안전효과를 분석하는 방법론을 제시하고자 한다. 협력형 차량 안전시스템의 도입 및 확산을 위해서는 사회적으로 어떠한 파급효과를 가져올지에 대하여 안전 시스템 별 정량적 분석이 필요하다. 국내에서 사고유형 기반으로 분석이 이루어진 사례들이 있으나, 사고 시나리오를 기반으로 한 분석방법론을 찾아보기 어렵다. 이러한 방법론을 제시하기 위해서 우선 승용차나 승합차만을 대상으로 한 국내 사망교통사고 데이터를 기반으로 사고 시나리오를 분류한다. 다음으로 사고 시나리오를 분석하여 협력형 차량 안전 시스템에 적용 가능한 시나리오를 선정하고 결과적으로 사망 사고 빈도수를 통해 안전 시스템의 잠재적인 사회적 안전효과를 정량적으로 제시한다. 마지막으로 안전효과의 정량적 분석을 이용하여 협력형 차량 안전 시스템의 인증을 위한 대표 평가 시나리오를 제시한다.

• 한국인터넷방송통신학회논문지
• /
• 제16권3호
• /
• pp.65-71
• /
• 2016

무선 페이딩 채널에서 시스템의 성능 저하를 효과적으로 개선하기 위하여 협동 릴레이 시스템에 관한 연구가 활발히 진행되고 있다. 그동안의 연구는 고정된 릴레이를 가정하였는데, 최근에는 실제 이동통신 환경을 고려하여 공간적으로 랜덤하게 분포된 릴레이를 갖는 협동 릴레이 시스템의 연구가 시작되고 있다. 특히 통신 자원의 효율이 높은 추가 기회전송 협동 릴레이 시스템에서는 릴레이를 선택하는 방법에 따라서 시스템의 성능이 변화하는데, 이에 대한 비교 연구는 발표되지 않았다. 따라서 본 논문에서는 최대 SNR 선택법과 최대-최소 SNR 선택법을 대상으로 최대비 결합을 사용한 추가 기회전송 협동 릴레이 시스템의 성능을 유도하였고, 송신전력이 소스와 릴레이로 배분되었을 때의 오수신율을 비교하였다. 본 논문의 해석적 결과는 이동통신 시스템에 기회전송 증가 릴레이 시스템을 도입하였을 경우 릴레이를 선택하고 송신 전력을 배분하는데 이론적 근거로 활용할 수 있을 것으로 생각된다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.648-651
• /
• 1997

This paper proposes methods for the cooperative control of multiple mobile robots and constructs a robotic soccer system in which the cooperation will be implemented as a pass play of two robots. To play a soccer game, elementary actions such as shooting and moving have been designed, and Q-learning, which is one of the popular methods for reinforcement learning, is used to determine what actions to take. Through simulation, learning is successful in case of deliberate initial arrangements of ball and robots, thereby cooperative work can be accomplished.

• Journal of Communications and Networks
• /
• 제12권5호
• /
• pp.442-448
• /
• 2010

Cooperative relaying methods have attracted a lot of interest in the past few years. A conventional cooperative relaying scheme has a source, a destination, and a single relay. This cooperative scheme can support one symbol transmission per time slot, and is caned full rate transmission. However, existing fun rate cooperative relay approaches provide asymmetrical gain for different transmitted symbols. In this paper, we propose a cooperative relaying scheme that is assisted with dual relays and provides full transmission rate with the same macro-diversity to each symbol. We also address equalization for the dual relay transmission system in addition to addressing the issues concerning the improvement of system performance in terms of optimal power allocations.