Amplify-and-Forward Cooperative Diversity for Green UWB-Based WBSNs by Heba Shaban, Mohamad Abou El-Nasr

“…In addition, it analyzes the bit-error-rate (BER) performance of the proposed nodes. …”
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DFT-SV-OFDM based adaptive multi-rate DFT scrambling vector code division multiple access by Gao ZHOU, Ping-zhi FAN, Li HAO

“…Multipath interference would degrade the performance of multi-rate systems based on OFDM and CDMA,which spectrum efficiency was also lower relatively.To improve the performance and spectrum efficiency,a novel adaptive multi-rate DFT scrambling vector multi-carrier CDMA (AMR-DFT-VMC-CDMA) was proposed based on the theory of matrix permutation and r-cyclical matrix decomposition characteristics.Meanwhile,by theoretical analysis,the parameters of the system could be adaptively adjusted to ensure frame length long enough to break the restriction between channel bit error rate and data frame length on a certain channel utilization condition.The simulation results show that compared with the traditional multi-rate,multi-subcarrier and spreading system,the new system could achieve multi-rate and multi-user information transmission flexibly with better performance and better spectrum efficiency in fading channels.Moreover,it can satisfy the requirement of frame length under certain channel utilization by adjusting the parameters.…”
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Exploring the nonlinear coded superposed modulation MISO visible light communication system by Zengyi XU, Wenqing NIU, Hui CHEN, Zhixue HE, Nan CHI

“…The light-emitting diode (LED) based visible light multi-input single-output (MISO) system usually suffers from the nonlinearity in LED and its incoherent nature in emission.Adopting precoding would alleviate this limitation at comparatively lower cost.Existing researches usually apply the same coding scheme to all the channels.An asymmetric coding scheme was proposed, which nonlinearly encodes one of the two channels in a MISO system.This solution enlarges the dynamic range of the uncoded channel at the cost of a higher bit error ratio (BER) in the coded one.When the BER threshold is set at 3.8×10^-3, the uncoded channel gains a dynamic range 30% larger than that of the coded one.If this solution is combined with flexible forward error correction redundancy, it would allow the system to adapt to varying channel condition while still maintaining the communication in both channels.This research would be beneficial in the study on indoor or underwater visible light communication (VLC) system.…”
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MUSTAFA KEMAL PAŞANIN MİLLÃŽ MÜCADELE LEHİNE KAMUOYU OLUŞTURMA ÇABALARI: BAZI İSTANBUL GAZETELERİ MUHABİRLERİYLE YAPTIĞI MÜLKAT VE VERDİĞİ DEMEÇLER by Osman Akandere

“…Millî hakimiyet esasına dayanan yeni bit Türk devleti kurmak gibi bir gayeyle Samsun'a çıkmış olan Mustafa Kemal Paşanın öncelikle ele aldığı konu, vatan bütünlüğünü ve millî istiklalini kaybetme noktasına gelmiş olan Türk Milletini karşı karşıya kaldığı tehlikenin büyüklüğü konusunda uyarmak, dağınık, çekingen ve  bölgesel kurtuluş çabalarını topyekün bir Millî Mücadele hareketine yöneltmek olmuştu. …”
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Pre-repeat cooperative GBN-ARQ for TDD/TDMA based wireless networks by Luo-bing DONG, Ke-chu YI, Pei-yi SHEN, Quan YU

“…An efficient pre-repeat cooperative go-back-N automatic repeat request(PC-GBN-CARQ)algorithm for slow fading TDD/TDMA-based Wireless Networks was proposed.Taking advantage of the multiple access property of TDMA,the proposed scheme enabled both the source and the relay to retransmit packets to the destination simultaneously,which could greatly increase the successful probability of the retransmission.When the source was sending a group of data packets,it also sent 8bit of attached message to tell the relay about which packets among the group would be probably error in transmission,which was the result predicted based on TDD reciprocity,so that the relay could also pre-retransmit these packets like the source does.It should be very effective to raise the transmission efficiency.Simulation results show that the proposed algorithms can get an S/N ratio gain of about 5dB compared with the conventional ones for the normalized throughput of 0.7.…”
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Iterative rake equalization method for low-complexity OTSM in high-speed mobile environment by Guojun LI, Kun LONG, Changrong YE, Jiawen LIANG

“…Aiming at the problems of poor anti-noise performance and high computational complexity of the existing orthogonal time sequency multiplexing (OTSM) equalization methods, a low-complexity iterative rake equalizer based on maximum ratio combining (MRC) was proposed.The main idea was to use MRC to iteratively extract and coherently combine the received multipath components of the transmitted symbols in the delay-time domain to improve the signal-to-noise ratio of the combined signal.In order to speed up the convergence of the MRC iterative algorithm, a single-tap time-frequency equalizer was designed to provide an initial estimate, and then combined with an external error correction code to further improve the bit error performance.The simulation results show that the performance of the iterative rake equalizer based on MRC is significantly better than that of the LMMSE linear equalizer, and the performance and computational complexity are greatly improved compared with the currently widely used Gauss-Seidel (GS) iterative equalizer.…”
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Packet-loss robust scalable authentication algorithm for compressed image streaming by Xiao-wei YI, Heng-tai MA, Gang ZHENG, Chang-wen ZHENG

“…To construct the authentication algorithm by hash chaining and error-correction coding, the proposed approach can realize optimizing bit-rate allocations and unequal authentication protection. …”
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Mémoires d’immigrés, mémoires de France? Mémoires et reconnaissance by Marine Corde

“…However one only needs to look a bit closer into history to discover that immigration to France is a very old element, which has played a part in the development of France not only economically but also politically, socially and culturally. …”
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Channel interleaver design and performance analysis for ultrasonic through-metal communication by Linsen XU, Wei YANG, Hongxian TIAN

“…Aiming at the problem that the UTM channel can produce successive error bits, a multiple input channel interleaver for UTM communication was proposed.By taking advantages of the grouping idea in multiple input interleaver and the periodic oscillation characteristic of the power gain in the UTM channel, encoded bits were first divided into several groups so that error probabilities of bits in each group varied smoothly.And then, the shift operation and the rectangular interleaver were applied to encoded bits in each group.This not only ensured that interleaved bits in the same group were dispersed into different oscillation cycles, which avoided that the successive bits suffer the high error probability, but also maintained the original bit position sequences, which reduced the influence of UEP.Approximate BER performances for the random interleaver and the proposed interleaver were analyzed and verified by simulation.Simulation results indicate that the proposed interleaver increases the frequency diversity of the UTM communication system and has a lower BER than the random interleaver at high SNR.…”
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Cache timing attack on SMS4 by ZHAO Xin-jie, WANG Tao, ZHENG Yuan-yuan

“…Two access driven Cache timing analysis methods on both first four rounds and last four rounds of SMS4 encryption were proposed and discussed.On the precondition of not interfering SMS4 encryption,a spy process was designed to gather the un-accessed lookup table related Cache sets during first four rounds and last four rounds of SMS4 encryption,then transferred them into impossible lookup table indices,combing plaintext or cipher text to analyze the impossible key byte candidates,finally the initial SMS4 key was recovered.Experiment results demonstrate that multi-process sharing Cache space feature and SMS4 lookup table structure decide that SMS4 is vulnerable to Cache timing attack,for about 80 samples are enough to recover full 128bit SMS4 key during both first four rounds attack and last four rounds attack,so it’s necessary to take certain countermeasures to prevent this kind of attack.…”
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Aquaculture Applications of the Family Gobiidae by Matt DiMaggio, Jesse Von Linden, Joshua Patterson, Cortney Ohs

“…DiMaggio and published by the UF/IFAS Program in Fisheries and Aquatic Sciences, School of Forest Resources and Conservation provides a brief overview of the family including description and taxonomy, natural history, culture techniques, a bit about disease challenges, and advice on marketing for ornamental Gobids. …”
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Improved RLCE public key encryption scheme based on Polar codes by Zhe LI, Yiliang HAN, Yu LI

“…For PolarRLCE has no semantic security and be vulnerable to adaptively chosen ciphertext attacks.Based onrandom linear code encryptionscheme,the structure of the RLCE scheme and Polar code polarization propertieswere used to make the Polar code as underlying encoding scheme,and through the method of RLCEspad message padding,a kind of improved public key encryption scheme which considers semantic security and can resistant toadaptively chosen ciphertext attacks was proposed.The improved scheme transformed the public key matrix into a system matrix and reduces the storage space of the public key.Some pre-computation for private key are estimated to reduce the storage space of private key.Through analysis,this scheme does not change the structure of PolarRLCE scheme,which can resist structural attacks against hamming quasi-cyclic codes.At the 128 bit security level,compared with HermitianRLCE scheme,GRSRLCE scheme and GoppaMcEliece scheme,the public key size of this scheme decreased by 4%,46.5% and 47.9% respectively.…”
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Generalized 2D polynomial chaotic map and its application in information transmission by Wenhao YAN, Zijing JIANG, Xin HUANG, Shujuan ZHU, Qun DING

“…Existing chaotic systems have many defects in engineering applications, such as discontinuous chaotic parameter range, weak chaos, uneven output of chaotic sequences and dynamic degradation.Therefore, a generalized 2D polynomial chaotic mapping model was proposed.By setting different control parameters and the highest degree of polynomial, a series of 2D robust chaotic maps with specific Lyapunov exponent could be obtained.In order to avoid the output of the second state equation collapsing to a fixed value, a random disturbance variable which did not change with time was introduced.Finally, a numerical example was given to verify the effectiveness of the proposed model, and the dynamic analysis showed that the mapping has complex dynamic behavior.Finally, the system was applied to information transmission technology.Compared with other chaotic maps, the system can achieve lower bit error rate, which indicates that the chaotic map is more suitable for chaotic information transmission.…”
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IoV vertical handoff research based on Bayesian decision by Cun-qun FAN, Shang-guang WANG, Qi-bo SUN, Hua ZOU, Fang-chun YANG

“…Firstly, according to the signal strength, transmission rate, bit error rate, blocking probability, vehicle speed and movement trend, the handoff probability distribution of Multi-condition was established and the handoff prior probability was calculated. …”
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DYNAMIC ANALYSIS AND SIMULATION OF FULL ROTARY BUILT-IN STEERING DRILLING TOOLS by ZHANG GuangWei, QIAO Yang, TIAN Fan, GAO SiTu, YIN FuLai

“…The full-rotation built-in steerable drilling tool is one of the important components of the rotary steerable drilling system.It is a new type of dynamic directional downhole closed-loop rotary steerable drilling tool.In order to study the motion condition of the full-rotation built-in rotary steerable drilling tool,based on the principle of space mechanism,The dynamics concentration parameter model of the full-rotation built-in directional drilling tool was established,and the system dynamics analysis was carried out.The correctness of the model was verified by ADAMS simulation.The results show that the basic parameters of velocity and attitude of the eccentric ring and the guide shaft of the key components are theoretically obtained,and the motion characteristics of the attitude mechanism are revealed.The rotational speed,eccentricity and bit motion of the eccentric ring and the guide shaft are studied.The relationship is obtained,and the variation of each parameter in the guiding system with time is obtained.It lays a theoretical foundation for the research of the full-rotation built-in directional drilling tool and the realization of the optimal design of the drilling system.…”
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Cognitive Waveform Design for Radar-Communication Transceiver Networks by Yu Yao, Lenan Wu

“…In addition to theoretical considerations, the simulation results show an improvement in target scattering coefficient (TSC) estimation and target detection probability as the number of iterations increases, while still transmitting data rates in the range of several Mbps with low bit error rates between CRC transceivers.…”
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Building method of distributed COW disk on network computing environment by Huai-liang TAN, Zheng LUO, Zai-hong HE, Ren-fa LI

“…Aiming to distributed computing and data centralizing storage in large-scale network computing environments and combining sparse and bursting characteristic of COW(copy-on-write) disk storing modified data blocks,the distributed COW network disk architecture was presented.The system building process of network computing environments was speeded up by apportioning the aggregation spending that server manages all related COW disks of client hosts to each client host.A improving 64bit bitmap compress arithmetic was designed to reduce the size of COW disk’s bitmap,so server disk space was saved and the network communication spending of distributed COW disk was less.The modified prefetching arithmetic based on COW bursting blocks was presented to improve the hit rate of Cache relating with distributed COW disk.Experiments on the prototype show that the distributed COW mechanism can effectively reduce system building latency of multi-client hosts network computing environment based on improving COW bitmap compress and prefetching arithmetic.…”
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Vertical handoff research based on cognitive self-selection decision tree by Cun-qun FAN, Shang-guang WANG, Qi-bo SUN, Hua ZOU, Fang-chun YANG

“…Firstly, according to the signal strength, transmission rate, bit error rate, blocking probability and movement trend, the respective handoff probability distribution of them was established and the decisions through the self-selection decision tree was made. …”
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Optimization of Embedded Mobile Teaching Model Based on Network Streaming Media Technology by Jing Tian

“…The system energy consumption, bit rate of video information, and buffer technology were optimized, respectively. …”
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Improved embedded wideband speech codec fitting EV-VBR standard by XIN Jie, BAO Chang-chun, JIA Mao-shen, LIU Xin

“…Based on the International Telecommunication Union Telecommunication Standardization Sector（ITU-T） recommendation for EV-VBR coding standard and the candidate codec designed by Speech and Audio Signal Processing Laboratory（SASPL） of Beijing University of Technology,an improved embedded variable bit rates wideband speech codec was proposed.In the improved codec,ACELP coding was implied to the first two coding layers.The middle sub-frame spectral parameters were computed and quantized.Three pulses depth first tree search algorithm was designed.On the higher three coding layers embedded TCX coding was reconstructed by accumulating frequency coefficients vectors.Addition-ally,VAD and DTX functions were implemented in the improved codec.Test results show that the improved codec achieves better speech quality and much lower coding complexity than the original codec.The speech quality and coding efficiency are comparable with G.718 of a new ITU-T speech coding standard and the low delay feature is retained.…”
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