Single Photon Detection Technology in Underwater Wireless Optical Communication:Modulation Modes and Error Correction Coding Analysis

This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding types on communication performance.The study investigates the impact of on-off keying(OOK)and 2-pulse-position modulation(2-PPM)on the bit error rate(BER)in single-channel intensity and polarization multiplexing.Furthermore,it compares the error correction performance of low-density parity check(LDPC)and Reed-Solomon(RS)codes across different error correction coding types.The effects of unscattered photon ratio and depolarization ratio on BER are also verified.Finally,a UWOC system based on SPD is constructed,achieving 14.58 Mbps with polarization OOK multiplexing modulation and 4.37 Mbps with polarization 2-PPM multiplexing modulation using LDPC code error correction.

Adaptation of the Two Sources of Code and One-Hot Encoding Method for Designing a Model of Microprogram Control Unit with Output Identification

This article presents a proposal for a model of a microprogram control unit (CMCU) with output identification adapted for implementation in complex programmable logic devices (CPLD) equipped with integrated memory modules [1]. An approach which applies two sources of code and one-hot encoding has been used in a base CMCU model with output identification [2] [3]. The article depicts a complete example of processing for the proposed CMCU model. Furthermore, it also discusses the advantages and disadvantages of the approach in question and presents the results of the experiments conducted on a real CPLD system.

Reconfigurable mechanism-based metamaterials for ternary-coded elastic wave polarizers and programmable refraction control

Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are frequency-dependent and unchangeable.Here,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties.Based on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are demonstrated.Particularly,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first achieved.Then,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative refraction.Finally,the wave functions with detailed microstructures are numerically verified.

The Application and Adaptation of the Two Sources of Code and Natural Encoding Method for Designing a Model of Microprogram Control Unit with Base Structure

The article presents a modification to the method which applies two sources of data. The modification is depicted on the example of a compositional microprogram control unit (CMCU) model with base structure implemented in the complex programmable logic devices (CPLD). First, the conditions needed to apply the method are presented, followed by the results of its implementation in real hardware.

Adoption of network and plan-do-check-action in the international classification of disease 10 coding

BACKGROUND with the widespread application of computer network systems in the medical field,the plan-do-check-action(PDCA)and the international classification of diseases tenth edition(ICD-10)coding system have also achieved favorable results in clinical medical record management.However,research on their combined application is relatively lacking.Objective:it was to explore the impact of network systems and PDCA management mode on ICD-10 encoding.Material and Method:a retrospective collection of 768 discharged medical records from the Medical Record Management Department of Meishan People’s Hospital was conducted.They were divided into a control group(n=232)and an observation group(n=536)based on whether the PDCA management mode was implemented.The two sets of coding accuracy,time spent,case completion rate,satisfaction,and other indicators were compared.AIM To study the adoption of network and PDCA in the ICD-10.METHODS A retrospective collection of 768 discharged medical records from the Medical Record Management Department of Meishan People’s Hospital was conducted.They were divided into a control group(n=232)and an observation group(n=536)based on whether the PDCA management mode was implemented.The two sets of coding accuracy,time spent,case completion rate,satisfaction,and other indicators were compared.RESULTS In the 3,6,12,18,and 24 months of PDCA cycle management mode,the coding accuracy and medical record completion rate were higher,and the coding time was lower in the observation group as against the controls(P<0.05).The satisfaction of coders(80.22%vs 53.45%)and patients(84.89%vs 51.72%)in the observation group was markedly higher as against the controls(P<0.05).CONCLUSION The combination of computer networks and PDCA can improve the accuracy,efficiency,completion rate,and satisfaction of ICD-10 coding.

Efficient fast mode decision using mode complexity for multi-view video coding

The variable block-size motion estimation(ME) and disparity estimation(DE) are adopted in multi-view video coding(MVC) to achieve high coding efficiency. However, much higher computational complexity is also introduced in coding system, which hinders practical application of MVC. An efficient fast mode decision method using mode complexity is proposed to reduce the computational complexity. In the proposed method, mode complexity is firstly computed by using the spatial, temporal and inter-view correlation between the current macroblock(MB) and its neighboring MBs. Based on the observation that direct mode is highly possible to be the optimal mode, mode complexity is always checked in advance whether it is below a predefined threshold for providing an efficient early termination opportunity. If this early termination condition is not met, three mode types for the MBs are classified according to the value of mode complexity, i.e., simple mode, medium mode and complex mode, to speed up the encoding process by reducing the number of the variable block modes required to be checked. Furthermore, for simple and medium mode region, the rate distortion(RD) cost of mode 16×16 in the temporal prediction direction is compared with that of the disparity prediction direction, to determine in advance whether the optimal prediction direction is in the temporal prediction direction or not, for skipping unnecessary disparity estimation. Experimental results show that the proposed method is able to significantly reduce the computational load by 78.79% and the total bit rate by 0.07% on average, while only incurring a negligible loss of PSNR(about 0.04 d B on average), compared with the full mode decision(FMD) in the reference software of MVC.

Fast Inter Coding Mode Selection Algorithm for H.264

In order to reduce the encoding complexity of macroblock coding mode decision in H.264/AVC, a selective smaller block-size searching algorithm and a selective intra coding mode searching algorithm are proposed by using the high correlation among coding modes and in spatial and temporal domains of video sequence. Simulation results demonstrate that the proposed algorithm can provide significant improvement in computational requirement, with negligible small picture quality degradation and slight bit rate increase.

Fast mode decision for Hierarchical-B pictures in scalable video coding

To decrease the computational complexity of adaptive inter-layer prediction and improve the encoding efficiency in sealable video coding, a mode decision algorithm is proposed by exploiting the part of used candidate modes of the co-located reference macrobloeks for Hierarchical-B pictures. This scheme reduces the amount of the candidate modes to generate a dynamic list for the current encoding macroblock according to the statistical information derived from the co-located reference macroblocks in different temporal levels. The experimental results show that this fast algorithm reduces approximately 31% encoding time on average with the negligible loss of encoding performance.

A SEMI-OPEN-LOOP CODING MODE SELECTION ALGORITHM BASED ON EFM AND SELECTED AMR-WB+ FEATURES

To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitation) classification are investigated.11 classifying features in the AMR-WB+ codec are selected and 2 novel classifying features,i.e.,EFM(Energy Flatness Measurement) and stdEFM(standard deviation of EFM),are proposed.Consequently,a novel semi-open-loop mode selection algorithm based on EFM and selected AMR-WB+ features is proposed.The results of classifying test and listening test show that the performance of the novel algorithm is much better than that of the AMR-WB+ semi-open-loop coding mode selection algorithm.

Effectiveness and failure modes of error correcting code in industrial 65 nm CMOS SRAMs exposed to heavy ions

Single event upsets(SEUs) induced by heavy ions were observed in 65 nm SRAMs to quantitatively evaluate the applicability and effectiveness of single-bit error correcting code(ECC) utilizing Hamming Code.The results show that the ECC did improve the performance dramatically,with the SEU cross sections of SRAMs with ECC being at the order of 10^(-11) cm^2/bit,two orders of magnitude higher than that without ECC(at the order of 10^(-9) cm^2/bit).Also,ineffectiveness of ECC module,including 1-,2- and 3-bits errors in single word(not Multiple Bit Upsets),was detected.The ECC modules in SRAMs utilizing(12,8) Hamming code would lose work when 2-bits upset accumulates in one codeword.Finally,the probabilities of failure modes involving 1-,2- and 3-bits errors,were calcaulated at 39.39%,37.88%and 22.73%,respectively,which agree well with the experimental results.

Spatial Models in Thinking and Communication

Spatial models joint external and internal aspects of human activity,mental schemas of thinking,and spatial structures of things.These models represent objects of knowledge,valuation,and transformation due to similarity with them in various relations,and they participate in inter-subject communication using schemata common for many people.The spatial models can reproduce a modelled object or be productive regarding it.These models are created in cognitive modus of comprehension as images of objects known at various mental levels;in projective modus,they appear as projects of object’s transformation and planes of subject’s actions;in communicative modus,they are interpreted as spatial texts expressing certain senses.All of them interact in spatial thinking,which deals with the relationship of parts and the whole,unlike logical thinking operating with genus-species relations.Both practical and theoretical thinking use common spatial schemas as means of internal modelling,which are elaborated in collective and individual experience.Due to their simplicity and unification,these schemas can serve also as units of spatial codes mediating the objects representation and inter-subject communication through spatial texts created in the semiotized space.

南京野生长江江豚行为谱及PAE编码系统

行为谱是依据对动物行为的辨识、分类等编制而成的行为目录,是深入开展动物行为生态学研究的重要基础和科学依据.2019—2023年,在南京长江江豚自然保护区内开展了112 d船只调查和10 d无人机定点监测,记录江豚出水4258次.本文构建了长江江豚的行为谱和PAE(姿势-动作-环境)编码系统,共定义P码13种,A码26种,E码10种,总计61种行为,归为10类:游动方式、生理功能行为、鳍肢行为、躯体行为、跳跃行为、社会行为、母子豚行为、捕食行为、交配行为和吐水行为.与铜陵半自然水域长江江豚相比较,有47种相同的行为,多数是江豚的基本生命活动所需,14种仅在南京江豚发生的行为可能是长江江豚对繁忙的航运产生的适应性对策,41种仅在铜陵半自然水域中发现的行为如冲突、滑行、悬挂等,可能与人工喂食等相关.部分行为在枯水期和丰水期、不同风力条件下出现的频率有显著差异,可能与育幼和环境适应性相关.本研究构建了野生江豚的行为谱和第一个PAE编码系统,对物种的保护与管理提供了重要参考.

生态环境法典的罪刑条款设置

“《刑法典》是环境刑法更好的归属”的观点,只是一种主观判断,不一定符合事实;我国清末以来的刑法典都预设了多元刑事立法模式,单一刑法典模式不是由刑法典自身形成的,而是由于其他法律不设置罪刑条款形成的,生态环境法典应当直接设置环境犯罪的罪刑条款;罪刑条款应当与行为规则、行政处罚条款密切接近,故应采取分散型设置方式;行政刑法的特点是通过补强行为规则,确保行为规则的有效性,故生态环境法典中的罪刑条款通常采取行政犯的表述方式,但部分条款也可以采取刑法犯的表述方式;罪刑条款应以行政处罚条款为基础,通过增加不法要素与责任要素的方式,使环境犯罪具备应受刑罚处罚性;处理行政处罚与刑罚处罚的关系时,重在防止以刑罚处罚替代行政处罚;应当将行为人积极履行《民法典》规定的“修复生态环境责任”,规定为环境犯罪的减免处罚事由;生态环境法典中的罪刑条款设置应注重必要性、明确性、合理性、协调性,不必顾虑与现行刑法典中环境犯罪条款的重复与交叉。

基于人脑知识双重编码理论的程序设计混合式教学实践

程序设计是管理类专业的学科基础课程,针对非计算机专业学生在课程学习中的“痛点”问题,基于人脑认知的双重编码理论来设计课程的总体框架。该文以对教学内容和教学组织形式进行重构,采用信息化技术手段驱动教学的反馈与反思,以学生为中心,依据学生学习过程中相互重叠的四种思考方式来完善教学设计,采用混合式团队教学模式,解决学生学习中的“痛点”问题。

稀疏网络编码中秩分布分析模型研究

针对现有稀疏网络编码研究中线性相关概率性能指标精准度较低的问题,提出基于马尔可夫链的性能分析模型。对线性相关概率、秩的概率分布等性能指标及其复杂度进行分析,并通过该性能分析模型分析编码包传输后期的译码成功概率;基于吸收马尔可夫链计算编码包传输过程中的瞬态、吸收态以及各状态间的状态转移概率,并对状态转移概率中蒙特卡罗模拟误差较大的问题进行改进,由状态转移概率构建吸收马尔可夫链基本矩阵,得出信宿端收到非再生包的线性相关概率,进而推导出秩的概率分布和译码成功概率性能指标。仿真结果表明,在相同条件下所提模型性能指标精确度均优于对比模型,且能精确地评估信宿端解码矩阵秩的概率分布、译码成功概率等稀疏网络编码的译码行为。

HEVC视频加密技术综述

针对视频数据在传输和存储过程中存在被非法获取和恶意破坏的问题,从高效视频编码(HEVC)标准和加密技术出发,对HEVC视频编码标准下的加密技术进行综述。回顾了视频编码技术的发展历程,介绍了HEVC视频编码标准,讨论了视频加密技术常见攻击方法及性能评估指标,全面梳理与详细分析了不同视频加密技术性能及其优缺点,展望了视频加密技术的发展趋势,旨在为视频加密技术的研究和应用提供参考。

西方体制Mark XIIA的Mode5数据格式分析

Mark XIIA是北约盟军统一研制的新型敌我识别系统,该系统的核心是Mode 5敌我识别。该文概述了Mark XIIA敌我识别系统的发展和系统组成,总结了Mode 5的4级工作模式,表明Mode 5不仅能完成基本的敌我识别功能,并具有态势感知、数据传输等功能;其次从安全性、数据容量、系统可靠性3个方面详细分析了Mode 5 Level 1和Level 2的数据格式特征,指出了Mode 5 Level 1和Level 2询问应答数据中的加解密数据段;最后,总结了Mode 5 IFF系统的特点。

QR code二维条码数据编码的研究

为了实现二维条码的超大容量和高效汉字表示,应用快速响应矩阵码(QRcode)进行编码.QRcode码可以对任何类型数据,如数字、字母、字节以及汉字等进行编码.汉字模式下输入字符被压缩成13bit二进制数,然后将二进制数连接起来,并在前面加上模式指示符、汉字子集指示符和字符计数指示符.在对输入数据进行汉字编码时,发现国家标准(GB/T18284—2000)中存在错误,生成的数据位流超出国标中规定的符号数据容量.提出了3种修订方法,修改了国标中汉字模式的数据容量.测试结果表明所提方法是可行和有效的.

一种基于图神经网络和统计分析的VVC帧内编码快速算法

多功能视频编码(versatile video coding,VVC)作为最新一代的视频编码标准,通过引入多种高效的编码工具进一步提升了视频编码性能。然而,VVC标准引入了四叉树加多类型树(quadtree plus multi-type tree,QTMT)划分结构,并将帧内预测模式从35种扩展到67种,导致编码复杂度急剧上升。为降低VVC的帧内编码复杂度,首先,提出了一种基于图神经网络的帧内编码单元(coding unit,CU)划分快速算法,该算法利用高效的图神经网络模型直接预测CU的最优划分模式,从而跳过冗余的CU划分遍历。其次,提出了一种基于空间相关性和纹理特征的帧内模式选择快速算法,该算法利用平均方向方差和Sobel梯度算子确定纹理方向,并跳过部分角度预测模式,同时结合预测模式间的相关性精简率失真模式列表。实验结果表明,该算法能够在BDBR(bjontegaard delta bit rate)上升2.29%的代价下,节省64.04%的编码时间。