Application of hybrid coded genetic algorithm in fuzzy neural network controller

Presents the fuzzy neural network optimized by hybrid coded genetic algorithm of decimal encoding and binary encoding, the searching ability and stability of genetic algorithms enhanced by using binary encoding during the crossover operation and decimal encoding during the mutation operation, and the way of accepting new individuals by probability adopted, by which a new individual is accepted and its parent is discarded when its fitness is higher than that of its parent, and a new individual is accepted by probability when its fitness is lower than that of its parent. And concludes with calculations made with an example that these improvements enhance the speed of genetic algorithms to optimize the fuzzy neural network controller.

Hybrid weighted symbol-flipping decoding for nonbinary LDPC codes

A hybrid decoding algorithm is proposed for nonbinary low-density parity-check （LDPC） codes, which combines the weighted symbol-flipping （WSF） algorithm with the fast Fourier trans- form q-ary sum-product algorithm （FFT-QSPA）. The flipped position and value are determined by the symbol flipping metric and the received bit values in the first stage WSF algorithm. If the low- eomplexity WSF algorithm is failed, the second stage FFT-QSPA is activated as a switching strategy. Simulation results show that the proposed hybrid algorithm greatly reduces the computational complexity with the performance close to that of FFT-QSPA.

An Efficient Test Data Compression Technique Based on Codes

This paper presents a new test data compression/decompression method for SoC testing,called hybrid run length codes. The method makes a full analysis of the factors which influence test parameters：compression ratio,test application time, and area overhead. To improve the compression ratio, the new method is based on variable-to-variable run length codes,and a novel algorithm is proposed to reorder the test vectors and fill the unspecified bits in the pre-processing step. With a novel on-chip decoder, low test application time and low area overhead are obtained by hybrid run length codes. Finally, an experimental comparison on ISCAS 89 benchmark circuits validates the proposed method

基于5G LDPC码的增强耦合编码及HARQ设计

针对CB级反馈场景,提出了一种基于现有的5G标准低密度一致校验码的增强耦合编码与混合自动重传方案,旨在提升5G链路数据传输的可靠性并改善其吞吐性能。具体而言,在FEC设计方面,基于5G LDPC码引入分组马尔可夫叠加传输技术,设计了BMST-5G-LDPC码,通过部分叠加耦合机制有效提升了传输可靠性;在HARQ设计方面,基于BMST-5G-LDPC码提出了一种兼容型HARQ方案,支持增量冗余IR和重复冗余RR机制。为进一步改善吞吐性能,特别提出了部分重传HARQ方案,通过对错误CB的部分比特进行重组并重传,节省信道传输资源改善吞吐性能,并同样支持IR和RR部分重传设计。仿真结果表明,所设计的BMST-5G-LDPC码在准静态衰落信道下相比传统5G LDPC码有约1.25 dB的性能增益;对于HARQ设计,兼容型HARQ设计相比于传统IR-HARQ方案,有10%以上吞吐增益;特别地,采用IR机制的PR-HARQ相比于传统IR-HARQ方案在中高噪比有20%以上的吞吐增益。

面向6G的多级编码调制技术

6G移动通信对高数据速率的需求推动了更高效的编码调制技术的发展。多级编码调制通过将数据分层并使用不同的编码和调制策略,能够有效降低编解码复杂度、提升频谱效率并增强系统的适应性和灵活性。简要介绍了5G通信系统中比特交织编码调制流程和优缺点。详细介绍了多级编码调制的基本原理、分层设计、发送和接收机制,以及基于多级编码调制的自适应重传方案。仿真表明,相比传统的比特交织编码调制,多级编码调制在高阶调制、高码率场景下能显著降低信道编解码的负荷,从而降低编解码的功耗。最后,结合研究现状,探讨了多级编码调制在未来6G通信系统中的潜力和面临的挑战。

Efficient Reliable Opportunistic Network Coding Based on Hybrid Flow in Wireless Network

Although the wireless network is widely used in many fields,its characteristics such as high bit error rate and broadcast links may block its development.Network coding is an artistic way to exploit its intrinsic characteristics to increase the network reliability.Some people research network coding schemes for inter-flow or intra-flow,each type with its own advantages and disadvantages.In this paper,we propose a new mechanism,called MM-NCOPE,which integrates the idea of inter-flow and intra-flow coding.On the one hand,MM-NCOPE utilizes random liner coding to encode the NCOPE packets while NCOPE is a sub-protocol for optimizing the COPE algorithm by iteration.In NCOPE,packets are automatically matched by size to be coded.As a result,it improves the coding gain in some level.On the other hand,we adopt the partial Acknowledgement retransmission scheme to achieve high compactness and robustness.ACK is an independent packet with the highest priority rather than a part of the data packets.Compared with existing works on opportunistic network coding,our approach ensures the reliability of wireless links and improves the coding gain.

Novel joint encoding/decoding algorithms of fountain codes for underwater acoustic communication

Fountain codes are considered to be a promising coding technique in underwater acoustic communication（UAC） which is challenged with the unique propagation features of the underwater acoustic channel and the harsh marine environment. And Luby transform（LT） codes are the first codes fully realizing the digital fountain concept. However, in conventional LT encoding/decoding algorithms, due to the imperfect coverage（IC） of input symbols and short cycles in the generator matrix, stopping sets would occur and terminate the decoding. Thus, the recovery probability is reduced,high coding overhead is required and decoding delay is increased.These issues would be disadvantages while applying LT codes in underwater acoustic communication. Aimed at solving those issues, novel encoding/decoding algorithms are proposed. First,a doping and non-uniform selecting（DNS） encoding algorithm is proposed to solve the IC and the generation of short cycles problems. And this can reduce the probability of stopping sets occur during decoding. Second, a hybrid on the fly Gaussian elimination and belief propagation（OFG-BP） decoding algorithm is designed to reduce the decoding delay and efficiently utilize the information of stopping sets. Comparisons via Monte Carlo simulation confirm that the proposed schemes could achieve better overall decoding performances in comparison with conventional schemes.

On Cross-Layer Design of AMC Based on Rate Compatible Punctured Turbo Codes

This paper extends the work on cross-layer design which combines adaptive modulation and coding at the physical layer and hybrid automatic repeat request protocol at the data link layer. By contrast with previous works on this topic, the present development and the performance analysis as well, is based on rate compatible punctured turbo codes. Rate compatibility provides incremental redundancy in transmission of parity bits for error correction at the data link layer. Turbo coding and iterative decoding gives lower packet error rate values in low signal-to-noise ratio regions of the adaptive modulation and coding (AMC) schemes. Thus, the applied cross-layer design results in AMC schemes can achieve better spectral efficiency than convolutional one while it retains the QoS requirements at the application layer. Numerical results in terms of spectral efficiency for both turbo and convolutional rate compatible punctured codes are presented. For a more comprehensive presentation, the performance of rate compatible LDPC is contrasted with turbo case as well as the performance complexity is discussed for each of the above codes.

Molecular characterization of LMW-GS genes from a somatic hybrid introgression line Ⅱ-12 between Triticum aestivum and Agropyron elongatum in relation to quick evolution

In order to exploit the evolution and find novel low-molecular-weight glutenin subunit （LMW-GS） for improvement of common wheat quality, thirteen variants from a somatic hybrid introgression line II-12 between Triticum aestivum cv. Jinan 177 （JN177） and Agropyron elongatum were characterized via genomic PCR. Four clones were pseudogenes because they contained an internal stop codon. The remaining nine variants contained intact open reading frames （ORFs）. Sequence alignment indicates that the proteins deduced from the nine ORFs have similar primary structure with LMW-GS cloned from its parents previously. However, they have some unique modifications in the structures. For example, EU292737 contains not only an extra Cys residue in the C-terminal domain but also a long repetitive domain. Both EU 159511 and EU292738 start their first Cys residue in the N-terminal repetitive domain, but not in the N-conserved domain traditionally. These structural alterations may have positive contributions to wheat flour quality. The results of phylogeny showed that most LMW-GS variances from 11-12 were homologous to those from parent JN177 and other wheat lines. The reason for quick evolution of LMW-GS in 11-12 was discussed.

Research of Hybrid Modulation Radar Signal

Based on the advantage of phase coded signal and stepped frequency signal,a new hybrid modulation signal is introduced in this paper. It combines phase code modulation during the pulse with stepped frequency modulation between the pulses, which is named as phase-coded stepped-frequency ( PCSF ) signal. By analyzing its waveform and ambiguity function,the comparison between Stepped-Frequency ( SF) signal and PCSF signal is given,which shows that the PCSF signal is better than SF signal. Finally,the signal processing method with two stage compressed processing is presented. The simulation results show that this new hybrid modulation radar signal can get a higher stepped frequency than ordinary SF signal,realize the same equivalent bandwidth with less pulse number,and solve the conflict among the stepped frequency,the number of pulse, and transmit average power. Under the premises of a certain range resolution,this new hybrid modulation radar signal not only raises the data rate of radar system,but also reduces Doppler sensitivity with a good prospect, and the effect of one-dimensional range profile is much better than that of traditional SF signal. Therefore,this new hybrid modulation radar signal can be widely used in application.

基于二维混合式位置编码的高精度测角

针对具有精密旋转轴系类的高端制造装备或精密测量仪器,其旋转角度采用传统圆光栅难以消除偏心误差对测量角度精度的影响,提出了一种基于二维混合式位置编码的旋转角度高精度测量方法。该测角系统由一个二维混合式位置编码盘、两个CCD相机和远心镜头组成,二维混合式位置编码盘被固定在精密旋转轴系上以获得其旋转角度。然后,建立了测角模型并从数学上证明了测角精度与安装偏心无关。利用多齿分度台对已提出测角系统精度进行检测,测量角度误差在±1″。最后,利用已提出测量方法对直驱转台的角度定位精度进行测量,角度定位误差在±5″内。与传统圆光栅测角相比,该方法不需要考虑安装偏心误差对测角精度的影响,具有稳定性好、使用简单等特点,可用于角度定位误差的检测。

无人机遥感反演小麦地上生物量模型的特征选择

无人机多光谱技术能快速、无损地测定小麦地上生物量(AGB)。然而,多光谱方法在计算植被特征时会产生大量具有高度相关的重复特征。因此,建立结构简单、精度高的模型对特征进行筛选具有重要意义。本文提出了一种可以同时实现特征筛选与参数优化的混合编码灰狼粒子群优化算法(CGWOPSO)。同时,为评估基于该算法驱动的极限梯度提升模型(CGWOPSO-XGB)的性能,将其及基于两种流行特征筛选方法(Pearson和SHAP方法)的模型(P-XGB和S-XGB)的反演AGB表现进行了对比。结果表明,S-XGB模型优于P-XGB模型,前者均方根误差(RMSE)比后者低3.0%~16.3%;而CGWOPSO-XGB模型精度高于S-XGB模型,前者RMSE比后者低16.0%。

Design of Digital Hybrid Chaotic Sequence Generator

The feasibility of the hybrid chaotic sequences as the spreading codes in code divided multiple access(CDMA) system is analyzed. The design and realization of the digital hybrid chaotic sequence generator by very high speed integrated circuit hardware description language(VHDL) are described. A valid hazard canceledl method is presented. Computer simulations show that the stable digital sequence waveforms can be produced. The correlations of the digital hybrid chaotic sequences are compared with those of m-sequences. The results show that the correlations of the digital hybrid chaotic sequences are almost as good as those of m-sequences. The works in this paper explored a road for the practical applications of chaos.

AOS中基于最优帧长的链路自适应联合优化方法

针对AOS中数据传输误码率高的问题,导致系统吞吐量低的问题,提出基于最优帧长的链路自适应联合优化方法。该方法以系统吞吐量最大化为目标,联合可变帧长,自适应编码调制和混合自动重传请求技术进行优化,根据信道状态信息分配下一帧传输最佳的帧长和编码调制方式,并对出错数据进行纠错和重传,最终提升系统吞吐量。仿真验证表明,与AMC-HARQ和AMC-ARQ方法相比,该方法在保证系统误帧率的同时,提高了系统的吞吐量。

基于神经网络的低码率语音编码技术研究综述

语音编码算法在无线或网络语音的传输过程中具有重要作用,在降低语音编码速率的同时确保编码语音质量不变甚至提升一直是设计者们追求的核心目标。然而,传统语音编解码器在较低速率下经过压缩后的语音音质、可懂度和有效带宽均有明显下降,极大程度上影响了用户的听觉体验。随着人工智能技术的不断进步,深度神经网络模型在语音处理任务中的应用也日益广泛,其性能普遍远超传统方法。在语音编解码领域,近年来很多研究也开始关注如何将神经网络模块融入编解码器,以实现更高效的语音传输,旨在低码率下实现传统方案无法达到的性能,为无线或网络语音传输提供新的解决方案。本文对基于神经网络的低码率语音编解码算法进行全面的整理分析和分类汇总,详细介绍了使用传统方法与神经网络结合的混合式编解码器以及使用编码器-解码器联合训练的端到端编解码器的发展历程、原理、特点及评价指标,并总结了这些方法的优势与不足。最后,结合当前各类编解码器的发展状况,对低速率语音编解码器的未来进行展望。基于神经网络的低码率语音编码技术有望解决实际通话中传输带宽受限时通话质量不佳的问题,为实时语音通信的进一步发展提供有力支持,并为未来压缩编码的研究方向提供新的思路。

面向重访周期需求的敏捷成像卫星任务规划方法

为满足敏捷成像星座观测目标的重访周期需求,提出一种混合编码差分进化算法.分析敏捷成像卫星的工作特点,构造评价重访周期需求满足情况的目标函数,建立成像任务约束满足模型.针对观测任务选择与否、执行顺序和成像时间的优化需求,提出一种二进制-实数混合编码差分进化算法,实现了成像任务在时间轴上的分布优化.通过工程实例进行仿真校验,仿真结果表明相比于基于二进制编码的遗传算法,本文算法在优化时间和优化效果方面都有较大优势.

Applications of Low-Emissivity Hybrid Insulation in South Korea

Low-Emissivity Hybrid Insulation has been developed in South Korea. It combines both resistive and reflective insulating principle. It is composed with many layers of reflective aluminum foils and honeycomb-structure air cells with polyethylene foam. This paper introduces recent South Korean building insulation code and the applications of Low-Emissivity Hybrid Insulation to meet the code.

《海牙规则》之回顾与启示

《海牙规则》是船货双方利益妥协的产物,以统一提单若干法律规则为宗旨,具有调整内容的限定性、法律规范的强制性和规则内容的明确性之特点,其实施至少在20世纪60年代基本实现了海上货物运输法律国际化,且对当前这一领域的国际化仍然发挥着基础性作用。《汉堡规则》和《鹿特丹规则》采用的承运人责任规则超出海上贸易实际需求,以及在上述特点方面存在不足,是其未能发挥实现海上货物运输法律国际化作用的主要原因。在正确认识海上货物运输条约与国内法的关系、立法的共性和差异基础上,中国在对参加《鹿特丹规则》持谨慎态度的同时,应当在《海商法》修改时积极借鉴或吸收该规则中合理和成熟的内容,优化《海商法》第四章采用的“混合制度”。

基于改进遗传算法的家庭用电调度优化方法

用电高峰期的用电需求给电力系统带来了巨大压力,因此优化家庭用电调度变得尤为重要。针对用电高峰期用户端存在的用电经济性及舒适度不够的问题,提出了一种基于改进遗传算法的家庭用电调度优化方法。首先以分时电价为基础,建立综合考虑用电经济性与用户满意度的家用电器调度模型,然后对不同类型的电器采取不同的编码方式来替代传统遗传算法的单一编码,并用带惩罚函数的适应度函数来约束各个电器用电任务所需时长等,以对传统遗传算法进行改进和用电行为优化。结果表明,所提算法可有效地依据分时电价实现用电负荷调度优化,在满足用户用电舒适度情况下为用户提供经济性的用电方案,且复杂度较低,能有效解决用电高峰期的用电经济性和舒适度问题。

基于重传错误率估计的自适应HARQ

自适应混合自动重传请求(hybrid automatic repeat request,HARQ)系统的性能与每次传输中的调制与编码方案(modulation and coding scheme,MCS)、发送功率选择密切相关,通过优化重传时的MCS及发送功率可以提升HARQ系统的吞吐率并降低能耗。由于不同MCS传输合并后的译码性能没有闭式解,这导致自适应HARQ优化问题不易解决。首先基于译码的判决域半径给出了一种HARQ合并后译码错误率的近似公式,进而提出了多种能权衡吞吐率和能耗性能的自适应HARQ优化策略。仿真结果验证了所提错误率估计方法的可靠性以及所提自适应HARQ的性能。与传统HARQ方案相比,所提方案能同时提高吞吐率、降低能耗,实现更好的吞吐率与能耗的性能折中。