• Title/Summary/Keyword: global networks

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The Smart City: Trends and Evolution, Readiness and Adaptability in Africa

  • Bashir Aliyu Yauri;Ekpobodo Raymond Ovwigho
    • International Journal of Computer Science & Network Security
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    • v.24 no.4
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    • pp.119-126
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    • 2024
  • This paper reviewed and provides clarifications as to the meaning and concept of Smart Cities with particular reference to the Smart City Components. The paper also discusses Internet of Things and the Big Data in relation to the role they played in the development and evolution of smart cities. The paper further provides discussions on the 5G Wireless Networks and Industry 4.0 buttressing their significance in the smart cities concept. The paper as the name implies; discusses on the readiness and adaptability of this trending concept 'Smart City' in the African global space.

Soft Computing Optimized Models for Plant Leaf Classification Using Small Datasets

  • Priya;Jasmeen Gill
    • International Journal of Computer Science & Network Security
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    • v.24 no.8
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    • pp.72-84
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    • 2024
  • Plant leaf classification is an imperative task when their use in real world is considered either for medicinal purposes or in agricultural sector. Accurate identification of plants is, therefore, quite important, since there are numerous poisonous plants which if by mistake consumed or used by humans can prove fatal to their lives. Furthermore, in agriculture, detection of certain kinds of weeds can prove to be quite significant for saving crops against such unwanted plants. In general, Artificial Neural Networks (ANN) are a suitable candidate for classification of images when small datasets are available. However, these suffer from local minima problems which can be effectively resolved using some global optimization techniques. Considering this issue, the present research paper presents an automated plant leaf classification system using optimized soft computing models in which ANNs are optimized using Grasshopper Optimization algorithm (GOA). In addition, the proposed model outperformed the state-of-the-art techniques when compared with simple ANN and particle swarm optimization based ANN. Results show that proposed GOA-ANN based plant leaf classification system is a promising technique for small image datasets.

New ODS Retrieval Service in the Mobile RFID Environment (모바일 RFID 환경에서 개선된 ODS 검색 서비스)

  • Oh, Jeong-Jin;Koh, Hyung-Dae;Choi, Han-Suk
    • The Journal of the Korea Contents Association
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    • v.8 no.12
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    • pp.45-52
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    • 2008
  • The Object Directory Service(ODS) of the mobile RFID is the core technology of the object information service for the object information retrieval among objects with RFID tags. The ODS service returns an URL information of a specific object application service after recognizing the mRFID tag in real time. The general ODS service is suitable for the global mRFID environment, but it is not good in the local networks and private networks that information security is needed. This paper proposes a new ODS service algorithm for the improvement of the general ODS service algorithm.

A Holistic Approach to Optimizing the Lifetime of IEEE 802.15.4/ZigBee Networks with a Deterministic Guarantee of Real-Time Flows

  • Kim, Kang-Wook;Park, Myung-Gon;Han, Junghee;Lee, Chang-Gun
    • Journal of Computing Science and Engineering
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    • v.9 no.2
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    • pp.83-97
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    • 2015
  • IEEE 802.15.4 is a global standard designed for emerging applications in low-rate wireless personal area networks (LR-WPANs). The standard provides beneficial features, such as a beacon-enabled mode and guaranteed time slots for realtime data delivery. However, how to optimally operate those features is still an open issue. For the optimal operation of the features, this paper proposes a holistic optimization method that jointly optimizes three cross-related problems: cluster-tree construction, nodes' power configuration, and duty-cycle scheduling. Our holistic optimization method provides a solution for those problems so that all the real-time packets can be delivered within their deadlines in the most energy-efficient way. Our simulation study shows that compared to existing methods, our holistic optimization can guarantee the on-time delivery of all real-time packets while significantly saving energy, consequently, significantly increasing the lifetime of the network. Furthermore, we show that our holistic optimization can be extended to take advantage of the spatial reuse of a radio frequency resource among long distance nodes and, hence, significantly increase the entire network capacity.

TCP Performance Enhancement by Implicit Priority Forwarding (IPF) Packet Buffering Scheme for Mobile IP Based Networks

  • Roh, Young-Sup;Hur, Kye-Ong;Eom, Doo-Seop;Lee, Yeon-Woo;Tchah, Kyun-Hyon
    • Journal of Communications and Networks
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    • v.7 no.3
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    • pp.367-376
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    • 2005
  • The smooth handoff supported by the route optimization extension to the mobile IP standard protocol should support a packet buffering mechanism at the base station (BS), in order to reduce the degradation in TCP performance caused by packet losses within mobile network environments. The purpose of packet buffering at the BS is to recover the packets dropped during intersubnetwork handoff by forwarding the packets buffered at the previous BS to the new BS. However, when the mobile host moves to a congested BS within a new foreign subnetwork, the buffered packets forwarded by the previous BS are likely to be dropped. This subsequently causes global synchronization to occur, resulting in the degradation of the wireless link in the congested BS, due to the increased congestion caused by the forwarded burst packets. Thus, in this paper, we propose an implicit priority forwarding (IPF) packet buffering scheme as a solution to this problem within mobile IP based networks. In the proposed IPF method, the previous BS implicitly marks the priority packets being used for inter-subnetwork handoff. Moreover, the proposed modified random early detection (M-RED) buffer at the new congested BS guarantees some degree of reliability to the priority packets. The simulation results show that the proposed IPF packet buffering scheme increases the wireless link utilization and, thus, it enhances the TCP throughput performance in the context of various intersubnetwork handoff cases.

A Highly Secure Identity-Based Authenticated Key-Exchange Protocol for Satellite Communication

  • Yantao, Zhong;Jianfeng, Ma
    • Journal of Communications and Networks
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    • v.12 no.6
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    • pp.592-599
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    • 2010
  • In recent years, significant improvements have been made to the techniques used for analyzing satellite communication and attacking satellite systems. In 2003, a research team at Los Alamos National Laboratory, USA, demonstrated the ease with which civilian global positioning system (GPS) spoofing attacks can be implemented. They fed fake signals to the GPS receiver so that it operates as though it were located at a position different from its actual location. Moreover, Galileo in-orbit validation element A and Compass-M1 civilian codes in all available frequency bands were decoded in 2007 and 2009. These events indicate that cryptography should be used in addition to the coding technique for secure and authenticated satellite communication. In this study, we address this issue by using an authenticated key-exchange protocol to build a secure and authenticated communication channel for satellite communication. Our protocol uses identity-based cryptography. We also prove the security of our protocol in the extended Canetti-Krawczyk model, which is the strongest security model for authenticated key-exchange protocols, under the random oracle assumption and computational Diffie-Hellman assumption. In addition, our protocol helps achieve high efficiency in both communication and computation and thus improve security in satellite communication.

Improved DV-Hop Localization Algorithm Based on Bat Algorithm in Wireless Sensor Networks

  • Liu, Yuan;Chen, Junjie;Xu, Zhenfeng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.1
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    • pp.215-236
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    • 2017
  • Obtaining accurate location information is important in practical applications of wireless sensor networks (WSNs). The distance vector hop (DV-Hop) is a frequently-used range-free localization algorithm in WSNs, but it has low localization accuracy. Moreover, despite various improvements to DV-Hop-based localization algorithms, maintaining a balance between high localization accuracy and good stability and convergence is still a challenge. To overcome these shortcomings, we proposed an improved DV-Hop localization algorithm based on the bat algorithm (IBDV-Hop) for WSNs. The IBDV-Hop algorithm incorporates optimization methods that enhance the accuracy of the average hop distance and fitness function. We also introduce a nonlinear dynamic inertial weight strategy to extend the global search scope and increase the local search accuracy. Moreover, we develop an updated solutions strategy that avoids premature convergence by the IBDV-Hop algorithm. Both theoretical analysis and simulation results show that the IBDV-Hop algorithm achieves higher localization accuracy than the original DV-Hop algorithm and other improved algorithms. The IBDV-Hop algorithm also exhibits good stability, search capability and convergence, and it requires little additional time complexity and energy consumption.

Distributed task allocation of mobile robotic sensor networks with guaranteed connectivity

  • Mi, Zhenqiang;Yu, Ruochen;Yi, Xiangtian;Yang, Yang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.12
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    • pp.4372-4388
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    • 2014
  • Robotic sensor network (RSN) contains mobile sensors and robots providing feasible solution for many multi-agent applications. One of the most critical issues in RSN and its application is how to effectively assign tasks. This paper presents a novel connectivity preserving hybrid task allocation strategy to answer the question particularly for RSN. Firstly, we model the task allocation in RSN to distinguish the discovering and allocating processes. Secondly, a fully distributed simple Task-oriented Unoccupied Neighbor Algorithm, named TUNA, is developed to allocate tasks with only partial view of the network topology. A connectivity controller is finally developed and integrated into the strategy to guarantee the global connectivity of entire RSN, which is critical to most RSN applications. The correctness, efficiency and scalability of TUNA are proved with both theoretical analysis and experimental simulations. The evaluation results show that TUNA can effectively assign tasks to mobile robots with the requirements of only a few messages and small movements of mobile agents.

Human Visual System based Automatic Underwater Image Enhancement in NSCT domain

  • Zhou, Yan;Li, Qingwu;Huo, Guanying
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.2
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    • pp.837-856
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    • 2016
  • Underwater image enhancement has received considerable attention in last decades, due to the nature of poor visibility and low contrast of underwater images. In this paper, we propose a new automatic underwater image enhancement algorithm, which combines nonsubsampled contourlet transform (NSCT) domain enhancement techniques with the mechanism of the human visual system (HVS). We apply the multiscale retinex algorithm based on the HVS into NSCT domain in order to eliminate the non-uniform illumination, and adopt the threshold denoising technique to suppress underwater noise. Our proposed algorithm incorporates the luminance masking and contrast masking characteristics of the HVS into NSCT domain to yield the new HVS-based NSCT. Moreover, we define two nonlinear mapping functions. The first one is used to manipulate the HVS-based NSCT contrast coefficients to enhance the edges. The second one is a gain function which modifies the lowpass subband coefficients to adjust the global dynamic range. As a result, our algorithm can achieve contrast enhancement, image denoising and edge sharpening automatically and simultaneously. Experimental results illustrate that our proposed algorithm has better enhancement performance than state-of-the-art algorithms both in subjective evaluation and quantitative assessment. In addition, our algorithm can automatically achieve underwater image enhancement without any parameter tuning.

Mechanism of Authentication Procedure between Ad Hoc Network and Sensor Network (에드 홉 네트워크와 개별 센서 네트워크 간의 인증 절차 메카니즘)

  • Kim, Seungmin;Yang, Jisoo;Kim, Hankyu;Kim, Jung Tae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.160-161
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    • 2013
  • Extending mobile IP to ad hoc networks with the foreign agent acting as the bridge between the wired network and ad hoc networks can provide the global Internet connectivity for ad hoc hosts. The existing research in the area of the integrated wired and ad hoc network is carried out in a non-adversarial setting. This paper analysed an effective solution to solve the security related problems encountered in these integrated networks. This security protocol also excludes malicious nodes from performing the ad hoc network routing. This paper focuses on preventing ad hoc hosts from the attacks of anti-integrity.

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