• Title/Summary/Keyword: adaptive protection

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A study on Scalable Video Coding Signals Transmission using inter-layer Differential OVSF code allocation scheme in MC-CDMA (MC-CDMA 기반의 SVC 전송 시스템에서 계층 간 차등 OVSF코드 할당 기법에 관한 연구)

  • Shin, Hyung-Song;Kim, Kyun-Tak;Lee, Kyu-Jin;Lee, Kye-San
    • Journal of Convergence Society for SMB
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    • v.6 no.3
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    • pp.49-55
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    • 2016
  • This paper proposes an adaptive video signal transmission scheme in order to ensure the QoS (Quality of Service) of user requirements. SVC (Scalable Video Coding) is an effective transmission scheme, because that can transmit video signal according to the video layer's weight. However, in previous works, those adaptive transmission systems which are considered about the various channel environments and user requirements have not been insufficiently studied. So, we propose the SVC signal transmission using inter-layer differential OVSF code allocation scheme in MC-CDMA. The proposed scheme is able to obtain each layer signal's protection order and control the sub-block of MC-CDMA by feedback information from receiver. Therefore, our proposed scheme is possible to provide the video quality for each users according to variable channel environments. The simulation results demonstrate the enhancement of proposed system in terms of BER performance.

Wavelet based data Watermarking (웨이브릿 기반의 데이터 워터마킹)

  • 김동현
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.6
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    • pp.1224-1228
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    • 2003
  • The use of digital imaging technique and digital contents based on internet has grown rapidly for last several years, and the needs of digital image protection become more important. For the purpose of copyright protection on digital image, the verification of authentication techniques like content authentication, ownership authentication, illegal copy and etc are needs. Digital watermarking, the invisible encryption technique to insert digital watermarking into image, the sophisticated perceptual information should be used for providing transparency and robustness of images on watermarking process. In this paper, we implement the algorithm for preventing forged attack. ownership protection and authentication by transforming the wavelet algorithms in frequency domain in terms of human visual system.

A Novel Shared Segment Protection Algorithm for Multicast Sessions in Mesh WDM Networks

  • Lu, Cai;Luo, Hongbin;Wang, Sheng;Li, Lemin
    • ETRI Journal
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    • v.28 no.3
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    • pp.329-336
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    • 2006
  • This paper investigates the problem of protecting multicast sessions in mesh wavelength-division multiplexing (WDM) networks against single link failures, for example, a fiber cut in optical networks. First, we study the two characteristics of multicast sessions in mesh WDM networks with sparse light splitter configuration. Traditionally, a multicast tree does not contain any circles, and the first characteristic is that a multicast tree has better performance if it contains some circles. Note that a multicast tree has several branches. If a path is added between the leave nodes on different branches, the segment between them on the multicast tree is protected. Based the two characteristics, the survivable multicast sessions routing problem is formulated into an Integer Linear Programming (ILP). Then, a heuristic algorithm, named the adaptive shared segment protection (ASSP) algorithm, is proposed for multicast sessions. The ASSP algorithm need not previously identify the segments for a multicast tree. The segments are determined during the algorithm process. Comparisons are made between the ASSP and two other reported schemes, link disjoint trees (LDT) and shared disjoint paths (SDP), in terms of blocking probability and resource cost on CERNET and USNET topologies. Simulations show that the ASSP algorithm has better performance than other existing schemes.

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Target-free vision-based approach for vibration measurement and damage identification of truss bridges

  • Dong Tan;Zhenghao Ding;Jun Li;Hong Hao
    • Smart Structures and Systems
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    • v.31 no.4
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    • pp.421-436
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    • 2023
  • This paper presents a vibration displacement measurement and damage identification method for a space truss structure from its vibration videos. Features from Accelerated Segment Test (FAST) algorithm is combined with adaptive threshold strategy to detect the feature points of high quality within the Region of Interest (ROI), around each node of the truss structure. Then these points are tracked by Kanade-Lucas-Tomasi (KLT) algorithm along the video frame sequences to obtain the vibration displacement time histories. For some cases with the image plane not parallel to the truss structural plane, the scale factors cannot be applied directly. Therefore, these videos are processed with homography transformation. After scale factor adaptation, tracking results are expressed in physical units and compared with ground truth data. The main operational frequencies and the corresponding mode shapes are identified by using Subspace Stochastic Identification (SSI) from the obtained vibration displacement responses and compared with ground truth data. Structural damages are quantified by elemental stiffness reductions. A Bayesian inference-based objective function is constructed based on natural frequencies to identify the damage by model updating. The Success-History based Adaptive Differential Evolution with Linear Population Size Reduction (L-SHADE) is applied to minimise the objective function by tuning the damage parameter of each element. The locations and severities of damage in each case are then identified. The accuracy and effectiveness are verified by comparison of the identified results with the ground truth data.

Adaptive Response Induced by Low Dose Ionizing Radiation in Human Lymphocytes (인체 말초 혈액 림프구에서 저선량 방사선 조사에 의해 유도되는 적응 반응)

  • Kim, Jeong-Hee;Lee, Kyung-Jong;Cho, Chul-Koo;Yoo, Seong-Yul;Kim, Tae-Hwan;Kim, Sung-Ho
    • Journal of Radiation Protection and Research
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    • v.20 no.2
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    • pp.97-102
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    • 1995
  • Adaptive response induced by low dose ${\gamma}-ray$ irradiation in human peripheral lymphocytes was examimed. Human lymphocytes were exposured to low dose of ${\gamma}-ray$ (priming dose, 0.01Gy) followed by high dose (challenging dose, 1.5Gy) after various time intervals (4, 7, 20 hours). Frequencies of micronuclei were enumerated in both primed and unprimed groups. Maximum reduction in frequency of micronuclei was observed when challenging dose irradiation was followed by priming dose after 4hr incubation period. When challenging doses were irradiated 7 or 20hr after priming dose, frequencies of micronuclei were reduced slighty. However, these reduction were not statistically significant. In this study, human peripheral lymphocytes were irradiated at Go phase and they showed adaptive response induced by low dose radiation. Since micronucleus assay is relatively simpler and faster than other methods, it may be a good tool for evaluating radiation-induced adaptive responses.

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Special Protection and Control Scheme for Transmission Line Overloading Elimination Based on Hybrid Differential Evolution/Electromagnetism-Like Algorithm

  • Hadi, Mahmood Khalid;Othman, Mohammad Lutfi;Wahab, Noor Izzri Abd
    • Journal of Electrical Engineering and Technology
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    • v.12 no.5
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    • pp.1729-1742
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    • 2017
  • In designing System Protection Schemes (SPSs) in power systems, protecting transmission network against extreme undesired conditions becomes a significant challenge in mitigating the transmission line overloading. This paper presents an intelligent Special Protection and Control Scheme (SPCS) using of Differential Evolution with Adaptive Mutation (DEAM) approach to obtain the optimum generation rescheduling to solve the transmission line overloading problem in system contingency conditions. DEAM algorithm employs the attraction-repulsion idea that is applied in the electromagnetism-like algorithm to support the mutation process of the conventional Differential Evolution (DE) algorithm. Different N-1 contingency conditions under base and increase load demand are considered in this paper. Simulation results have been compared with those acquired from Genetic Algorithm (GA) application. Minimum severity index has been considered as the objective function. The final results show that the presented DEAM method offers better performance than GA in terms of faster convergence and less generation fuel cost. IEEE 30-bus test system has been used to prove the effectiveness and robustness of the proposed algorithm.

Parametric Evaluation Method of Protectability in a Distribution System (파라메터 관점에서의 배전계통 보호도 평가방법)

  • Cho, P.S.;Hyun, S.H.;Lim, S.I.;Lee, S.J.;Lee, D.S.;Waldemar, Waldemar
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.241-243
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    • 2002
  • Recently, great efforts are concentrated on the autonomous, adaptive protection schemes with advanced artificial intelligence and digital technology. It is highly required for a next generation protective system not only to detect and to clear a fault, but also to fit itself to the changing environment. In this paper it is suggested an evaluation method for the protection ability of a protective system in a distributed system. The suggested method is of bottom-up scheme, in other words, protection ability is estimated from the lowest level of parameters in each protective devices to the highest level of the whole protective system. This feature makes it possible to evaluate the protection ability either for the protective device(or a system), or for a protected system. And, in addition, it is enabled that the protectability concept can be applied in the design stage of a protective system for a distribution network. The proposed method is applied to a simple distributed network to show its effectiveness.

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Priority-based Unequal Error Protection Scheme of Data partitioned H.264 video with Hierarchical QAM

  • Chen, Rui;Wu, Minghu;Yang, Jie;Rui, Xiongli
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.4189-4202
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    • 2014
  • In this paper, we propose a priority-based unequal error protection scheme of data partitioned H.264/AVC video with hierarchical quadrature amplitude modulation. In order to map data with higher priority onto the most significant bits of QAM constellation points, a priority sorting method categorizes different data partitions according to the unequal importance factor of encoded video data in one group of pictures by evaluated the average distortion. Then we propose a hierarchical quadrature amplitude modulation arrangement with adaptive constellation distances, which takes into account the unequal importance of encoded video data and the channel status. Simulation results show that the proposed scheme improves the received video quality by about 2 dB in PSNR comparing with the state-of-the-art unequal error protection scheme, and outperforms EEP scheme by up to 5 dB when the average channel SNR is low.

Genetic Diversity of Orobanche cumana Populations in Serbia

  • Ivanovic, Zarko;Marisavljevic, Dragana;Marinkovic, Radovan;Mitrovic, Petar;Blagojevic, Jovana;Nikolic, Ivan;Pavlovic, Danijela
    • The Plant Pathology Journal
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    • v.37 no.6
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    • pp.512-520
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    • 2021
  • In this study, we report genetic characterization of Orobanche cumana, the causal agent of sunflower wilting in Serbia. The genetic diversity of this parasitic plant in Serbia was not studied before. Random amplified polymorphic DNA (RAPD) markers and partial rbcL gene sequences analysis were used to characterize the O. cumana populations at the molecular level. While phylogenetic analyses of RAPD-PCR amplicons were performed using unweighted pair-group Method analyses, rbcL gene sequences were analyzed using neigbor joining method and minimum spanning tree. Molecular analyses of RAPD-PCR analysis revealed high genetic diversity of O. cumana populations which indicated high adaptive potential of this parasitic weed in Serbia. Further analyses of rbcL gene using minimum spanning tree revealed clear differences among diverse sections of Orobanche genus. Although this molecular marker lacked the resolution to display intrapopulation diversity it could be a useful tool for understanding the evolution of this parasitic plant. Our results suggested that O. cumana has great genetic potential which can lead to differentiation of more virulent races which is important for determining crop breeding strategies for their control.

Adaptive High-order Variation De-noising Method for Edge Detection with Wavelet Coefficients

  • Chenghua Liu;Anhong Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.2
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    • pp.412-434
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    • 2023
  • This study discusses the high-order diffusion method in the wavelet domain. It aims to improve the edge protection capability of the high-order diffusion method using wavelet coefficients that can reflect image information. During the first step of the proposed diffusion method, the wavelet packet decomposition is a more refined decomposition method that can extract the texture and structure information of the image at different resolution levels. The high-frequency wavelet coefficients are then used to construct the edge detection function. Subsequently, because accurate wavelet coefficients can more accurately reflect the edges and details of the image information, by introducing the idea of state weight, a scheme for recovering wavelet coefficients is proposed. Finally, the edge detection function is constructed by the module of the wavelet coefficients to guide high-order diffusion, the denoised image is obtained. The experimental results showed that the method presented in this study improves the denoising ability of the high-order diffusion model, and the edge protection index (SSIM) outperforms the main methods, including the block matching and 3D collaborative filtering (BM3D) and the deep learning-based image processing methods. For images with rich textural details, the present method improves the clarity of the obtained images and the completeness of the edges, demonstrating its advantages in denoising and edge protection.