• Title/Summary/Keyword: Computer Networks

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An Advanced Resource Allocation Algorithm for PON-LTE Converged Networks

  • Abhishek Gaur;Vibhakar Shrimali
    • International Journal of Computer Science & Network Security
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    • v.23 no.7
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    • pp.16-22
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    • 2023
  • Enhanced radio access technologies (RAT) are deployed in Next Generation Convergence Networks by the service providers so as to satisfy the basic requirements of end-users for e.g. QoS. Whenever the available resources are being shared simultaneously and dynamically by multiple users or distribution of allocated channels randomly, the deficiency of spectral resources and dynamic behavior of Network traffic in real time Networking, we may have problem. In order to evaluate the performance of our proposed algorithm, computer simulation has been performed on NS-2 simulator and a comparison with the existing algorithms has been made.

Weight Distribution of Neural Networks in Computer Vision (컴퓨터 비전에서 신경망의 가중치 분포)

  • Wu, Chenmou;Lee, Hyo-Jon
    • Annual Conference of KIPS
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    • 2022.11a
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    • pp.594-596
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    • 2022
  • Over the last decades, deep neural networks have demonstrated significant success in various tasks. To address the special vision task, choosing a hot network as backbone to extract feature is a common way in both research and industry project. However, the choice of backbone usually requires the expert experience and affects the performance of the classification task. In this work, we propose a novel idea to support backbone decision-making by exploring the feature attribution and weights distribution of hidden layers from various backbones. We first analyze the visualization of feature maps on different size object and different depth layers to observe learning ability. Then, we compared the variance of weights and feature in last three layers. Based on analysis of the feature and wights, we summarize the traits and commonalities of existing networks.

Bi-LSTM model with time distribution for bandwidth prediction in mobile networks

  • Hyeonji Lee;Yoohwa Kang;Minju Gwak;Donghyeok An
    • ETRI Journal
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    • v.46 no.2
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    • pp.205-217
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    • 2024
  • We propose a bandwidth prediction approach based on deep learning. The approach is intended to accurately predict the bandwidth of various types of mobile networks. We first use a machine learning technique, namely, the gradient boosting algorithm, to recognize the connected mobile network. Second, we apply a handover detection algorithm based on network recognition to account for vertical handover that causes the bandwidth variance. Third, as the communication performance offered by 3G, 4G, and 5G networks varies, we suggest a bidirectional long short-term memory model with time distribution for bandwidth prediction per network. To increase the prediction accuracy, pretraining and fine-tuning are applied for each type of network. We use a dataset collected at University College Cork for network recognition, handover detection, and bandwidth prediction. The performance evaluation indicates that the handover detection algorithm achieves 88.5% accuracy, and the bandwidth prediction model achieves a high accuracy, with a root-mean-square error of only 2.12%.

Enhanced Secure Sensor Association and Key Management in Wireless Body Area Networks

  • Shen, Jian;Tan, Haowen;Moh, Sangman;Chung, Ilyong;Liu, Qi;Sun, Xingming
    • Journal of Communications and Networks
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    • v.17 no.5
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    • pp.453-462
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    • 2015
  • Body area networks (BANs) have emerged as an enabling technique for e-healthcare systems, which can be used to continuously and remotely monitor patients' health. In BANs, the data of a patient's vital body functions and movements can be collected by small wearable or implantable sensors and sent using shortrange wireless communication techniques. Due to the shared wireless medium between the sensors in BANs, it may be possible to have malicious attacks on e-healthcare systems. The security and privacy issues of BANs are becoming more and more important. To provide secure and correct association of a group of sensors with a patient and satisfy the requirements of data confidentiality and integrity in BANs, we propose a novel enhanced secure sensor association and key management protocol based on elliptic curve cryptography and hash chains. The authentication procedure and group key generation are very simple and efficient. Therefore, our protocol can be easily implemented in the power and resource constrained sensor nodes in BANs. From a comparison of results, furthermore, we can conclude that the proposed protocol dramatically reduces the computation and communication cost for the authentication and key derivation compared with previous protocols. We believe that our protocol is attractive in the application of BANs.

A scheme on multi-tier heterogeneous networks for citywide damage monitoring in an earthquake

  • Fujiwara, Takahiro;Watanabe, Takashi;Shinozuka, Masanobu
    • Smart Structures and Systems
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    • v.11 no.5
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    • pp.497-510
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    • 2013
  • Quick, accurate damage monitoring is strongly required for damage assessment in the aftermath of a large natural disaster. Wireless sensor networks are promising technologies to acquire damage information in a citywide area. The wireless sensor networks, however, would be faced with difficulty to collect data in real-time and to expand the scalability of the networks. This paper discusses a scheme of network architecture to cove a whole city in multi-tier heterogeneous networks, which consist of wireless sensor networks, access networks and a backbone network. We first review previous studies for citywide damage monitoring, and then discuss the feature of multi-tier heterogeneous networks to cover a citywide area.

Trust-aware secure routing protocol for wireless sensor networks

  • Hu, Huangshui;Han, Youjia;Wang, Hongzhi;Yao, Meiqin;Wang, Chuhang
    • ETRI Journal
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    • v.43 no.4
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    • pp.674-683
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    • 2021
  • A trust-aware secure routing protocol (TSRP) for wireless sensor networks is proposed in this paper to defend against varieties of attacks. First, each node calculates the comprehensive trust values of its neighbors based on direct trust value, indirect trust value, volatilization factor, and residual energy to defend against black hole, selective forwarding, wormhole, hello flood, and sinkhole attacks. Second, any source node that needs to send data forwards a routing request packet to its neighbors in multi-path mode, and this continues until the sink at the end is reached. Finally, the sink finds the optimal path based on the path's comprehensive trust values, transmission distance, and hop count by analyzing the received packets. Simulation results show that TSRP has lower network latency, smaller packet loss rate, and lower average network energy consumption than ad hoc on-demand distance vector routing and trust based secure routing protocol.

Automatic Mobile Screen Translation Using Object Detection Approach Based on Deep Neural Networks (심층신경망 기반의 객체 검출 방식을 활용한 모바일 화면의 자동 프로그래밍에 관한 연구)

  • Yun, Young-Sun;Park, Jisu;Jung, Jinman;Eun, Seongbae;Cha, Shin;So, Sun Sup
    • Journal of Korea Multimedia Society
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    • v.21 no.11
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    • pp.1305-1316
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    • 2018
  • Graphical user interface(GUI) has a very important role to interact with software users. However, designing and coding of GUI are tedious and pain taking processes. In many studies, the researchers are trying to convert GUI elements or widgets to code or describe formally their structures by help of domain knowledge of stochastic methods. In this paper, we propose the GUI elements detection approach based on object detection strategy using deep neural networks(DNN). Object detection with DNN is the approach that integrates localization and classification techniques. From the experimental result, if we selected the appropriate object detection model, the results can be used for automatic code generation from the sketch or capture images. The successful GUI elements detection can describe the objects as hierarchical structures of elements and transform their information to appropriate code by object description translator that will be studied at future.

Interpolation based Single-path Sub-pixel Convolution for Super-Resolution Multi-Scale Networks

  • Alao, Honnang;Kim, Jin-Sung;Kim, Tae Sung;Oh, Juhyen;Lee, Kyujoong
    • Journal of Multimedia Information System
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    • v.8 no.4
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    • pp.203-210
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    • 2021
  • Deep leaning convolutional neural networks (CNN) have successfully been applied to image super-resolution (SR). Despite their great performances, SR techniques tend to focus on a certain upscale factor when training a particular model. Algorithms for single model multi-scale networks can easily be constructed if images are upscaled prior to input, but sub-pixel convolution upsampling works differently for each scale factor. Recent SR methods employ multi-scale and multi-path learning as a solution. However, this causes unshared parameters and unbalanced parameter distribution across various scale factors. We present a multi-scale single-path upsample module as a solution by exploiting the advantages of sub-pixel convolution and interpolation algorithms. The proposed model employs sub-pixel convolution for the highest scale factor among the learning upscale factors, and then utilize 1-dimension interpolation, compressing the learned features on the channel axis to match the desired output image size. Experiments are performed for the single-path upsample module, and compared to the multi-path upsample module. Based on the experimental results, the proposed algorithm reduces the upsample module's parameters by 24% and presents slightly to better performance compared to the previous algorithm.

A study of handover for dynamic QoS in B3G networks (B3G 네트워크에서 동적 QoS를 위한 핸드오버 연구)

  • Park, Sang-Joon;Lee, Jong-Chan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.3
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    • pp.1373-1379
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    • 2011
  • The SLA (Service Level Agreement) is once determined between service provider and users in B3G networks so that the network service must be provided as QoS management. Here, the network situation is changed as the time flow, and the service environment is also altered. Hence, dynamic QoS management scheme should be considered. In this paper, we propose a handover scheme for dyanamic QoS as the network situation in B3G networks. The heterogeneous networks can be used for dynamic QoS management in B3G networks.

An Adaptive FEC Code Control Algorithm for Mobile Wireless Sensor Networks

  • Ahn Jong-Suk;Hong Seung-Wook;Heidemann John
    • Journal of Communications and Networks
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    • v.7 no.4
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    • pp.489-498
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    • 2005
  • For better performance over a noisy channel, mobile wireless networks transmit packets with forward error correction (FEC) code to recover corrupt bits without retransmission. The static determination of the FEC code size, however, degrades their performance since the evaluation of the underlying channel state is hardly accurate and even widely varied. Our measurements over a wireless sensor network, for example, show that the average bit error rate (BER) per second or per minute continuously changes from 0 up to $10^{-3}$. Under this environment, wireless networks waste their bandwidth since they can't deterministically select the appropriate size of FEC code matching to the fluctuating channel BER. This paper proposes an adaptive FEC technique called adaptive FEC code control (AFECCC), which dynamically tunes the amount of FEC code per packet based on the arrival of acknowl­edgement packets without any specific information such as signal to noise ratio (SNR) or BER from receivers. Our simulation experiments indicate that AFECCC performs better than any static FEC algorithm and some conventional dynamic hybrid FEC/ARQ algorithms when wireless channels are modeled with two-state Markov chain, chaotic map, and traces collected from real sensor networks. Finally, AFECCC implemented in sensor motes achieves better performance than any static FEC algorithm.