• 제목/요약/키워드: Computer Networks

검색결과 5,189건 처리시간 0.027초

Power Control with Nearest Neighbor Nodes Distribution for Coexisting Wireless Body Area Network Based on Stochastic Geometry

  • Liu, Ruixia;Wang, Yinglong;Shu, Minglei;Zhao, Huiqi;Chen, Changfang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권11호
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    • pp.5218-5233
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    • 2018
  • The coexisting wireless body area networks (WBAN) is a very challenging issue because of strong inter-networks interference, which seriously affects energy consumption and spectrum utilization ratio. In this paper, we study a power control strategy with nearest neighbor nodes distribution for coexisting WBAN based on stochastic geometry. Using homogeneous Poisson point processes (PPP) model, the relationship between the transmission power and the networks distribution is analytically derived to reduce interference to other devices. The goal of this paper is to increase the transmission success probability and throughput through power control strategy. In addition, we evaluate the area spectral efficiency simultaneously active WBAN in the same channel. Finally, extensive simulations are conducted to evaluate the power control algorithm.

A Learning Algorithm of Fuzzy Neural Networks with Trapezoidal Fuzzy Weights

  • Lee, Kyu-Hee;Cho, Sung-Bae
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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    • pp.404-409
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    • 1998
  • In this paper, we propose a learning algorithm of fuzzy neural networks with trapezoidal fuzzy weights. This fuzzy neural networks can use fuzzy numbers as well as real numbers, and represent linguistic information better than standard neural networks. We construct trapezodal fuzzy weights by the composition of two triangles, and devise a learning algorithm using the two triangular membership functions, The results of computer simulations on numerical data show that the fuzzy neural networks have high fitting ability for target output.

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컴퓨터 네트웍에서의 경로선정 :알고리즘의 개관 (Routing in Computer Networks: A Survey of Algorithms)

  • 차동완;정남기;장석권
    • 한국경영과학회지
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    • 제9권2호
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    • pp.46-55
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    • 1984
  • The purpose of this parer is to provide a survey of the state of the art of routing methods in store-and-forward computer networks. The survey is carried out in line with a new taxonomy: heuristic methods, user-optimization methods, and system-optimization methods. This taxonomy on routing algorithms is based on two viewpoints: the level of optimization and the relative difficulty for the implementation in real computer networks. Some actual methods implemented in real computer networks are surveyed as well as the theoretical studies in the literature. This paper concludes with some points in need of further researches.

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A Congestion Control Mechanism for Supporting Differentiated Service in Mobile Ad hoc Networks

  • Kim Jin-Nyun;Ha Nam-Koo;Cho Dong-Hoon;Kim Hyun-Sook;Han Ki-Jun
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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    • pp.143-146
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    • 2004
  • Differentiated services (DiffServ) has been widely accepted as the service model to adopt for providing quality-of­service (QoS) over the next-generation IP networks. There is a growing need to support QoS in mobile ad hoc networks. Supporting DiffServ in mobile ad hoc networks, however, is very difficult because of the dynamic nature of mobile ad hoc networks, which causes network congestion. The network congestion induces long transfer packet delay and low throughput which make it very difficult to support QoS in mobile ad hoc networks. We propose DiffServ module to support differentiated service in mobile ad hoc networks through congestion control. Our DiffServ module uses the periodical rate control for real time traffic and also uses the best effort bandwidth concession when network congestion occurs. Network congestion is detected by measuring the packet transfer delay or bandwidth threshold of real time traffic. We evaluate our mechanism via a simulation study. Simulation results show our mechanism may offer a low and stable delay and a stable throughput for real time traffic in mobile ad hoc networks.

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연구 활동과 과학 지식 생산성에 있어서 학술 연구 전산망의 역할 (The Role of Academic and Research Computer Networks in Research Activities and Productivity of Scientists and Engineers)

  • 조명희
    • 정보관리학회지
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    • 제7권1호
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    • pp.96-120
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    • 1990
  • 학술 연구 전산망은 연구자에게 정보 자원과 부가 가치가 높은 정보 서비스를 제공 하며 결과적으로 연구자의 연구 활동과 연구 생산성에 큰 변수로써 영향을 미치고 있다. 본 고는 연구자들간에 유용한 정보 유통 도구로써 정착해 가고 있는 학술 연구 전산망의 제기 능과 연구 활동에 있어서 그의 역할을 고찰하였으며, 한국의 학술 연구 전산망 현상을 조사 분석하고 그 방향을 전망하였다.

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An Energy-Efficient Multicast Algorithm with Maximum Network Throughput in Multi-hop Wireless Networks

  • Jiang, Dingde;Xu, Zhengzheng;Li, Wenpan;Yao, Chunping;Lv, Zhihan;Li, Tao
    • Journal of Communications and Networks
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    • 제18권5호
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    • pp.713-724
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    • 2016
  • Energy consumption has become a main problem of sustainable development in communication networks and how to communicate with high energy efficiency is a significant topic that researchers and network operators commonly concern. In this paper, an energy-efficient multicast algorithm in multi-hop wireless networks is proposed aiming at new generation wireless communications. Traditional multi-hop wireless network design only considers either network efficiency or minimum energy consumption of networks, but rarely the maximum energy efficiency of networks. Different from previous methods, the paper targets maximizing energy efficiency of networks. In order to get optimal energy efficiency to build network multicast, our proposed method tries to maximize network throughput and minimize networks' energy consumption by exploiting network coding and sleeping scheme. Simulation results show that the proposed algorithm has better energy efficiency and performance improvements compared with existing methods.

A SURVEY ON INTRUSION DETECTION SYSTEMS IN COMPUTER NETWORKS

  • Zarringhalami, Zohreh;Rafsanjani, Marjan Kuchaki
    • Journal of applied mathematics & informatics
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    • 제30권5_6호
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    • pp.847-864
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    • 2012
  • In recent years, using computer networks (wired and wireless networks) has been widespread in many applications. As computer networks become increasingly complex, the accompanied potential threats also grow to be more sophisticated and as such security has become one of the major concerns in them. Prevention methods alone are not sufficient to make them secure; therefore, detection should be added as another defense before an attacker can breach the system. Intrusion Detection Systems (IDSs) have become a key component in ensuring systems and networks security. An IDS monitors network activities in order to detect malicious actions performed by intruders and then initiate the appropriate countermeasures. In this paper, we present a survey and taxonomy of intrusion detection systems and then evaluate and compare them.

Link Prediction Algorithm for Signed Social Networks Based on Local and Global Tightness

  • Liu, Miao-Miao;Hu, Qing-Cui;Guo, Jing-Feng;Chen, Jing
    • Journal of Information Processing Systems
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    • 제17권2호
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    • pp.213-226
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    • 2021
  • Given that most of the link prediction algorithms for signed social networks can only complete sign prediction, a novel algorithm is proposed aiming to achieve both link prediction and sign prediction in signed networks. Based on the structural balance theory, the local link tightness and global link tightness are defined respectively by using the structural information of paths with the step size of 2 and 3 between the two nodes. Then the total similarity of the node pair can be obtained by combining them. Its absolute value measures the possibility of the two nodes to establish a link, and its sign is the sign prediction result of the predicted link. The effectiveness and correctness of the proposed algorithm are verified on six typical datasets. Comparison and analysis are also carried out with the classical prediction algorithms in signed networks such as CN-Predict, ICN-Predict, and PSNBS (prediction in signed networks based on balance and similarity) using the evaluation indexes like area under the curve (AUC), Precision, improved AUC', improved Accuracy', and so on. Results show that the proposed algorithm achieves good performance in both link prediction and sign prediction, and its accuracy is higher than other algorithms. Moreover, it can achieve a good balance between prediction accuracy and computational complexity.

Exploring Efficient Solutions for the 0/1 Knapsack Problem

  • Dalal M. Althawadi;Sara Aldossary;Aryam Alnemari;Malak Alghamdi;Fatema Alqahtani;Atta-ur Rahman;Aghiad Bakry;Sghaier Chabani
    • International Journal of Computer Science & Network Security
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    • 제24권2호
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    • pp.15-24
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    • 2024
  • One of the most significant issues in combinatorial optimization is the classical NP-complete conundrum known as the 0/1 Knapsack Problem. This study delves deeply into the investigation of practical solutions, emphasizing two classic algorithmic paradigms, brute force, and dynamic programming, along with the metaheuristic and nature-inspired family algorithm known as the Genetic Algorithm (GA). The research begins with a thorough analysis of the dynamic programming technique, utilizing its ability to handle overlapping subproblems and an ideal substructure. We evaluate the benefits of dynamic programming in the context of the 0/1 Knapsack Problem by carefully dissecting its nuances in contrast to GA. Simultaneously, the study examines the brute force algorithm, a simple yet comprehensive method compared to Branch & Bound. This strategy entails investigating every potential combination, offering a starting point for comparison with more advanced techniques. The paper explores the computational complexity of the brute force approach, highlighting its limitations and usefulness in resolving the 0/1 Knapsack Problem in contrast to the set above of algorithms.

5th Generation Wireless Networks Security: Challenges and Solutions

  • Siddiq, Bashayer Ahmed Bin
    • International Journal of Computer Science & Network Security
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    • 제22권6호
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    • pp.157-162
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    • 2022
  • In reason of the high capacity and low latency, the 5G wireless networks used nowadays in many of life applications such as: remote surgery and guiding vehicle. The high requirements of 5G networks makes it more vulnerable for security threats and attacks. This paper presents some challenges faced by 5G networks and presets some of the security solutions.