• 한국전자통신학회논문지
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• 제15권3호
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• pp.445-450
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• 2020

협력 네트워크는 전송기에서 송신기로 신호를 전송할 때 여러 개의 중계기를 통해 신호를 전송함으로써 통신성능을 향상시키고 전송용량을 증가시키는 장점을 제공한다. 본 논문에서는 송신기와 중계기 사이에서는 일반적인 이진변조방식을 이용하여 신호를 전송하고 중계기와 수신기 사이에서는 차등 공간 시간 코드 방식을 적용한 신호전송 시스템을 고려한다. 먼저 송신기와 중계기 사이에서 동기방식과 차등변조 방식을 적용했을 때의 성능을 분석한다. 변조방식 및 중계기의 개수를 고려한 다양한 중계기 위치에서의 성능 또한 비교한다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2009년도 추계학술발표대회
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• pp.917-918
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• 2009

This study evaluated the level of performance improvement in the form of a simulated experiment by adding fixed node in the middle of the network as a way to improve mobile ad.hoc network performance. The result showed that the performance level was much higher when fixed node was used together than when mobile node was used only, and the comparison of the mobile speed of mobile node also showed that use of fixed node together had higher performance. Moreover, the evaluation in accordance with the number of fixed node showed that more number of fixed node had shorter time delay. Further study following this on how many fixed node should be added on the ad.hoc network will ensure establishment of more reliable ad.hoc network.

• 대한기계학회논문집
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• 제17권12호
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• pp.3007-3019
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• 1993

For the same configuration, the stiffness of 6-node two dimensional isoparametric is stiffer than that of 8-node two dimensional isoparametric element. This phenomenon may be called 'Relative Stiffness Stiffening Phenomenon.' In this paper, the relative stiffness stiffening phenomenon was studied, and could be corrected by modifying the position of Gauss integral points used in the numerical integration of the stiffness matrix. For the same deformation (bending) energy of 6-node and 8-node two dimensional isoparametric elements, Gauss integral points of 6-node element have to move closer, in comparison with those of 8-node element, in the case of numerical integration along the thickness direction.

• 항공우주시스템공학회지
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• 제15권4호
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• pp.75-84
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• 2021

A novel robot-operating-system-based flight and mission state communication node for X-Plane 11 flight control simulation environments and its simulation results were discussed. Although the proposed communication method requires considerable implementation steps compared with the conventional MATLAB/Simulink-based User Datagram Protocol (UDP) block utilization method, the proposed method enables a direct comparison of cockpit-view images captured during flight with the flight data. This comparison is useful for data acquisition under virtual environments and for the development of flight control systems. The fixed/rotary-wing and ground terrain elements simulated in virtual environments exhibited excellent visualization outputs, which can overcome time and space constraints on flight experiments and validation of missionary algorithms with complex logic.

• International Journal of Advanced Culture Technology
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• 제10권1호
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• pp.47-54
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• 2022

We analyze and compare the structure of the networks of Netflix, Disney+, and OCN, which are forerunners in OTT market, on Twitter. This study employs NodeXL pro as a visualization software package for social network analysis. As a result of the comparison with values of Vertices, Connected Components, Average Geodesic Distance, Average Betweenness Centrality, and Average Closeness Centrality. Netflix has comparative advantages at Vertices, Connected Components, and Average Closeness Centrality, OCN at Average Geodesic Distance, and Disney+ at Average Betweenness Centrality. Netflix has a more appropriate social network for influencer marketing than Disney+ and OCN. Based on the analysis results, the purpose of this study is to explain the structural differences in the social networks of Netflix, Disney+, and OCN in terms of influencer marketing.

• 한국시뮬레이션학회논문지
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• 제21권2호
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• pp.69-78
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• 2012

본 논문에서는 애드혹 무선 네트워크에서 채널 전송속도를 높일 수 있는 협력통신 기법에서 도움노드를 선정하는 방법에 대한 연구를 수행하였다. 송수신 노드가 RTS/CTS 제어 프레임을 서로 교환한 이후에 도움노드를 선정하는 사후선정 기법을 채용한 참고문헌 연구결과를 컴퓨터 모의실험을 사용하여 성능비교를 수행하기 위해 시뮬레이터를 구현하였다. 성능평가 척도는 시스템 처리량과 채널 액세스 지연시간을 사용하였으며, 통신노드는 모두 지정된 통신영역 내에서 독립적으로 이동하는 모델을 사용하였다. 성능비교와 장단점 분석을 통해 취합된 결과는 성능이 우수한 새로운 도움노드 선정기법을 설계하는데 귀중한 자료가 될 것으로 판단된다.

• 전기학회논문지
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• 제59권12호
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• pp.2329-2336
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• 2010

Hierarchical tree routing is a inefficient routing method of transmitting data in a wireless sensor network. Zigbee routing which is made to improve inefficiency of the hierarchical tree routing only fulfills the tree routing when a destination node don't exists in neighbor nodes of a router. We suggest a TFSR algorithm that is improved more than the zigbee routing. The TFSR algorithm generates a family set included a parent node and child nodes and over of a destination node, and uses this information. According to simulation results, the TFSR algorithm reduce routing costs over 30 percent in comparison with the hierarchical tree routing and the zigbee routing.

• 스마트미디어저널
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• 제5권4호
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• pp.41-48
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• 2016

In mobile ad hoc networks(MANETs), all the nodes in a network have limited resources. Therefore, communication topology which has long lifetime is suitable for nodes in MANETs. And MANETs are exposed to various threats because of a new node which can join the network at any time. There are various researches on security problems in MANETs and many researches have tried to make efficient schemes for reducing network power consumption. Power consumption is necessary to secure networks, however too much power consumption can be critical to network lifetime. This paper focuses on energy efficient monitoring node distribution for enhancing network lifetime in MANETs. Since MANETs cannot use centralized infrastructure such as security systems of wired networks, we propose an efficient IDS node distribution scheme using minimum spanning tree (MST) method to cover all the nodes in a network and enhance the network lifetime. Simulation results show that the proposed algorithm has better performance in comparison with the existing algorithms.

• 대한전자공학회논문지SP
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• 제38권1호
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• pp.54-68
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• 2001

본 논문은 2D 영상에서 겹쳐진 물체를 분리하기 위한 새로운 기법을 제안한다. 제안된 알고리즘은 겹쳐진 물체를 분리하는 보편적인 기법으로서의 매칭 알고리즘이 가지는 계산상의 부담을 줄이고자 하였다. 영상에서의 물체의 표현은 attributed graph를 사용하며, 각 node와 arc는 물체의 면과 면간의 관계에 각각 대응시킨다 또한, 각 arc는 그 parameter로서 관계계수를 가지며 이는 arc를 중심으로 양 끝에 존재하는 임의의 node의 상대 node에 대한 가려짐 상태에 의해 정의된다. 각 node는 이웃 node와의 관계에 의해 다양한 패턴으로 분류되며, 제안된 패턴을 이용하여 node들의 homogeneity를 검사한다. 끝으로, Homogeneity를 만족하는 node들을 하나의 집합(node set)으로 grouping함으로써, 가려진 물체와 가리는 물체를 분리하게 된다. 본 논문에서 제안한 알고리즘은 임의의 형태로 놓여있는 겹쳐진 물체를 효율적으로 분리하고 있으며, 매칭단계 이전에 물체를 분리함으로써 매칭에 필요한 시간부담을 크게 줄일 수 있음을 실험을 통해 보여주고 있다.

• International Journal of Computer Science & Network Security
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• 제23권10호
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• pp.169-178
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• 2023

Wireless sensor network is wieldy use for IoT application. The sensor node consider as physical device in IoT architecture. This all sensor node are operated with battery so the power consumption is very high during the data communication and low during the sensing the environment. Without proper planning of data communication the network might be dead very early so primary objective of the cluster based routing protocol is to enhance the battery life and run the application for longer time. In this paper we have comprehensive of twenty research paper related with clustering based routing protocol. We have taken basic information, network simulation parameters and performance parameters for the comparison. In particular, we have taken clustering manner, node deployment, scalability, data aggregation, power consumption and implementation cost many more points for the comparison of all 20 protocol. Along with basic information we also consider the network simulation parameters like number of nodes, simulation time, simulator name, initial energy and communication range as well energy consumption, throughput, network lifetime, packet delivery ration, jitter and fault tolerance parameters about the performance parameters. Finally we have summarize the technical aspect and few common parameter must be fulfill or consider for the design energy efficient cluster based routing protocol.