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Separate Source Channel Coding Is Still What You Need:An LLM-Based Rethinking
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作者 REN Tianqi LI Rongpeng +5 位作者 ZHAO Mingmin CHEN Xianfu LIU Guangyi YANG Yang ZHAO Zhifeng ZHANG Honggang 《ZTE Communications》 2025年第1期30-44,共15页
Along with the proliferating research interest in semantic communication(Sem Com),joint source channel coding(JSCC)has dominated the attention due to the widely assumed existence in efficiently delivering information ... Along with the proliferating research interest in semantic communication(Sem Com),joint source channel coding(JSCC)has dominated the attention due to the widely assumed existence in efficiently delivering information semantics.Nevertheless,this paper challenges the conventional JSCC paradigm and advocates for adopting separate source channel coding(SSCC)to enjoy a more underlying degree of freedom for optimization.We demonstrate that SSCC,after leveraging the strengths of the Large Language Model(LLM)for source coding and Error Correction Code Transformer(ECCT)complemented for channel coding,offers superior performance over JSCC.Our proposed framework also effectively highlights the compatibility challenges between Sem Com approaches and digital communication systems,particularly concerning the resource costs associated with the transmission of high-precision floating point numbers.Through comprehensive evaluations,we establish that assisted by LLM-based compression and ECCT-enhanced error correction,SSCC remains a viable and effective solution for modern communication systems.In other words,separate source channel coding is still what we need. 展开更多
关键词 separate source channel coding(SSCC) joint source channel coding(JSCC) end-to-end communication system Large Language Model(LLM) lossless text compression Error Correction Code Transformer(ECCT)
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Intrusion Detection Model Using Chaotic MAP for Network Coding Enabled Mobile Small Cells
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作者 Chanumolu Kiran Kumar Nandhakumar Ramachandran 《Computers, Materials & Continua》 SCIE EI 2024年第3期3151-3176,共26页
Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),a... Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),are essential due to the limitations of simpler security measures,such as cryptography and firewalls.Due to their compact nature and low energy reserves,wireless networks present a significant challenge for security procedures.The features of small cells can cause threats to the network.Network Coding(NC)enabled small cells are vulnerable to various types of attacks.Avoiding attacks and performing secure“peer”to“peer”data transmission is a challenging task in small cells.Due to the low power and memory requirements of the proposed model,it is well suited to use with constrained small cells.An attacker cannot change the contents of data and generate a new Hashed Homomorphic Message Authentication Code(HHMAC)hash between transmissions since the HMAC function is generated using the shared secret.In this research,a chaotic sequence mapping based low overhead 1D Improved Logistic Map is used to secure“peer”to“peer”data transmission model using lightweight H-MAC(1D-LM-P2P-LHHMAC)is proposed with accurate intrusion detection.The proposed model is evaluated with the traditional models by considering various evaluation metrics like Vector Set Generation Accuracy Levels,Key Pair Generation Time Levels,Chaotic Map Accuracy Levels,Intrusion Detection Accuracy Levels,and the results represent that the proposed model performance in chaotic map accuracy level is 98%and intrusion detection is 98.2%.The proposed model is compared with the traditional models and the results represent that the proposed model secure data transmission levels are high. 展开更多
关键词 Network coding small cells data transmission intrusion detection model hashed message authentication code chaotic sequence mapping secure transmission
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The Application of Nicotiana benthamiana as a Transient Expression Host to Clone the Coding Sequences of Plant Genes
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作者 Jianzhong Huang Peng Jia +3 位作者 Xiaoju Zhong Xiuying Guan Hongbin Zhang Honglei Ruan 《American Journal of Molecular Biology》 CAS 2024年第2期54-65,共12页
Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using co... Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using complementary DNA (cDNA) derived from messenger RNA (mRNA) extracted from plant tissues and generated by reverse transcription. However, some CDS are difficult to acquire through this process as they are expressed at extremely low levels or have specific spatial and/or temporal expression patterns in vivo. These challenges require the development of alternative CDS cloning technologies. In this study, we found that the genomic intron-containing gene coding sequences (gDNA) from Arabidopsis thaliana, Oryza sativa, Brassica napus, and Glycine max can be correctly transcribed and spliced into mRNA in Nicotiana benthamiana. In contrast, gDNAs from Triticum aestivum and Sorghum bicolor did not function correctly. In transient expression experiments, the target DNA sequence is driven by a constitutive promoter. Theoretically, a sufficient amount of mRNA can be extracted from the N. benthamiana leaves, making it conducive to the cloning of CDS target genes. Our data demonstrate that N. benthamiana can be used as an effective host for the cloning CDS of plant genes. 展开更多
关键词 coding Sequence Genomic Sequence Nicotiana benthamiana Plant Genes
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A quantum blind signature scheme based on dense coding for non-entangled states
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作者 邢柯 殷爱菡 薛勇奇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期220-228,共9页
In some schemes, quantum blind signatures require the use of difficult-to-prepare multiparticle entangled states. By considering the communication overhead, quantum operation complexity, verification efficiency and ot... In some schemes, quantum blind signatures require the use of difficult-to-prepare multiparticle entangled states. By considering the communication overhead, quantum operation complexity, verification efficiency and other relevant factors in practical situations, this article proposes a non-entangled quantum blind signature scheme based on dense encoding. The information owner utilizes dense encoding and hash functions to blind the information while reducing the use of quantum resources. After receiving particles, the signer encrypts the message using a one-way function and performs a Hadamard gate operation on the selected single photon to generate the signature. Then the verifier performs a Hadamard gate inverse operation on the signature and combines it with the encoding rules to restore the message and complete the verification.Compared with some typical quantum blind signature protocols, this protocol has strong blindness in privacy protection,and higher flexibility in scalability and application. The signer can adjust the signature operation according to the actual situation, which greatly simplifies the complexity of the signature. By simultaneously utilizing the secondary distribution and rearrangement of non-entangled quantum states, a non-entangled quantum state representation of three bits of classical information is achieved, reducing the use of a large amount of quantum resources and lowering implementation costs. This improves both signature verification efficiency and communication efficiency while, at the same time, this scheme meets the requirements of unforgeability, non-repudiation, and prevention of information leakage. 展开更多
关键词 quantum blind signature dense coding non-entanglement Hadamard gate
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Decoding topological XYZ^(2) codes with reinforcement learning based on attention mechanisms
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作者 陈庆辉 姬宇欣 +2 位作者 王柯涵 马鸿洋 纪乃华 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期262-270,共9页
Quantum error correction, a technique that relies on the principle of redundancy to encode logical information into additional qubits to better protect the system from noise, is necessary to design a viable quantum co... Quantum error correction, a technique that relies on the principle of redundancy to encode logical information into additional qubits to better protect the system from noise, is necessary to design a viable quantum computer. For this new topological stabilizer code-XYZ^(2) code defined on the cellular lattice, it is implemented on a hexagonal lattice of qubits and it encodes the logical qubits with the help of stabilizer measurements of weight six and weight two. However topological stabilizer codes in cellular lattice quantum systems suffer from the detrimental effects of noise due to interaction with the environment. Several decoding approaches have been proposed to address this problem. Here, we propose the use of a state-attention based reinforcement learning decoder to decode XYZ^(2) codes, which enables the decoder to more accurately focus on the information related to the current decoding position, and the error correction accuracy of our reinforcement learning decoder model under the optimisation conditions can reach 83.27% under the depolarizing noise model, and we have measured thresholds of 0.18856 and 0.19043 for XYZ^(2) codes at code spacing of 3–7 and 7–11, respectively. our study provides directions and ideas for applications of decoding schemes combining reinforcement learning attention mechanisms to other topological quantum error-correcting codes. 展开更多
关键词 quantum error correction topological quantum stabilizer code reinforcement learning attention mechanism
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Recurrent neural network decoding of rotated surface codes based on distributed strategy
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作者 李帆 李熬庆 +1 位作者 甘启迪 马鸿洋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期322-330,共9页
Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error corre... Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error correction using neural network-based machine learning methods is a promising approach that is adapted to physical systems without the need to build noise models.In this paper,we use a distributed decoding strategy,which effectively alleviates the problem of exponential growth of the training set required for neural networks as the code distance of quantum error-correcting codes increases.Our decoding algorithm is based on renormalization group decoding and recurrent neural network decoder.The recurrent neural network is trained through the ResNet architecture to improve its decoding accuracy.Then we test the decoding performance of our distributed strategy decoder,recurrent neural network decoder,and the classic minimum weight perfect matching(MWPM)decoder for rotated surface codes with different code distances under the circuit noise model,the thresholds of these three decoders are about 0.0052,0.0051,and 0.0049,respectively.Our results demonstrate that the distributed strategy decoder outperforms the other two decoders,achieving approximately a 5%improvement in decoding efficiency compared to the MWPM decoder and approximately a 2%improvement compared to the recurrent neural network decoder. 展开更多
关键词 quantum error correction rotated surface code recurrent neural network distributed strategy
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Single Photon Detection Technology in Underwater Wireless Optical Communication:Modulation Modes and Error Correction Coding Analysis
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作者 GAI Lei LI Wendong WANG Guoyu 《Journal of Ocean University of China》 CAS CSCD 2024年第2期405-414,共10页
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 type... 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. 展开更多
关键词 error correction coding modulation mode single photon detection underwater communication wireless optical communication
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On Zero Dynamics and Controllable Cyber-Attacks in Cyber-Physical Systems and Dynamic Coding Schemes as Their Countermeasures
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作者 Mahdi Taheri Khashayar Khorasani Nader Meskin 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第11期2191-2203,共13页
In this paper, we study stealthy cyber-attacks on actuators of cyber-physical systems(CPS), namely zero dynamics and controllable attacks. In particular, under certain assumptions, we investigate and propose condition... In this paper, we study stealthy cyber-attacks on actuators of cyber-physical systems(CPS), namely zero dynamics and controllable attacks. In particular, under certain assumptions, we investigate and propose conditions under which one can execute zero dynamics and controllable attacks in the CPS. The above conditions are derived based on the Markov parameters of the CPS and elements of the system observability matrix. Consequently, in addition to outlining the number of required actuators to be attacked, these conditions provide one with the minimum system knowledge needed to perform zero dynamics and controllable cyber-attacks. As a countermeasure against the above stealthy cyber-attacks, we develop a dynamic coding scheme that increases the minimum number of the CPS required actuators to carry out zero dynamics and controllable cyber-attacks to its maximum possible value. It is shown that if at least one secure input channel exists, the proposed dynamic coding scheme can prevent adversaries from executing the zero dynamics and controllable attacks even if they have complete knowledge of the coding system. Finally, two illustrative numerical case studies are provided to demonstrate the effectiveness and capabilities of our derived conditions and proposed methodologies. 展开更多
关键词 Controllable attacks cyber-physical systems(CPS) dynamic coding zero dynamics attacks stealthy cyber-attacks
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Improved Segmented Belief Propagation List Decoding for Polar Codes with Bit-Flipping
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作者 Mao Yinyou Yang Dong +1 位作者 Liu Xingcheng Zou En 《China Communications》 SCIE CSCD 2024年第3期19-36,共18页
Belief propagation list(BPL) decoding for polar codes has attracted more attention due to its inherent parallel nature. However, a large gap still exists with CRC-aided SCL(CA-SCL) decoding.In this work, an improved s... Belief propagation list(BPL) decoding for polar codes has attracted more attention due to its inherent parallel nature. However, a large gap still exists with CRC-aided SCL(CA-SCL) decoding.In this work, an improved segmented belief propagation list decoding based on bit flipping(SBPL-BF) is proposed. On the one hand, the proposed algorithm makes use of the cooperative characteristic in BPL decoding such that the codeword is decoded in different BP decoders. Based on this characteristic, the unreliable bits for flipping could be split into multiple subblocks and could be flipped in different decoders simultaneously. On the other hand, a more flexible and effective processing strategy for the priori information of the unfrozen bits that do not need to be flipped is designed to improve the decoding convergence. In addition, this is the first proposal in BPL decoding which jointly optimizes the bit flipping of the information bits and the code bits. In particular, for bit flipping of the code bits, a H-matrix aided bit-flipping algorithm is designed to enhance the accuracy in identifying erroneous code bits. The simulation results show that the proposed algorithm significantly improves the errorcorrection performance of BPL decoding for medium and long codes. It is more than 0.25 d B better than the state-of-the-art BPL decoding at a block error rate(BLER) of 10^(-5), and outperforms CA-SCL decoding in the low signal-to-noise(SNR) region for(1024, 0.5)polar codes. 展开更多
关键词 belief propagation list(BPL)decoding bit-flipping polar codes segmented CRC
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Angular-tunable on-chip coding metasurface enabled by phase-change material with immersion liquid
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作者 LI Xue-Nan ZHAO Zeng-Yue +4 位作者 YU Fei-Long CHEN Jin LI Guan-Hai LI Zhi-Feng CHEN Xiao-Shuang 《红外与毫米波学报》 CSCD 北大核心 2024年第6期806-812,共7页
Metasurfaces provide a potent platform for the dynamic manipulation of electromagnetic waves.Coupled with phase-change materials,they facilitate the creation of versatile metadevices,showcasing various tunable functio... Metasurfaces provide a potent platform for the dynamic manipulation of electromagnetic waves.Coupled with phase-change materials,they facilitate the creation of versatile metadevices,showcasing various tunable functions based on the transition between amorphous and crystalline states.However,the inherent limitation in tunable states imposes constraints on the multiplexing channels of metadevices.Here,this paper introduces a novel approach-a multi-functional metadevice achieved through the two-level control of the encoding phasechange metaatoms.Utilizing the phase-change material Ge_(2)Sb_(2)Se_(4)Te1(GSST)and high refractive-index liquid diiodomethane(CH_(2)I_(2)),this paper showcases precise control over electromagnetic wave manipulation.The GSST state governs the tunable function,switching it ON and OFF,while the presence of liquid in the hole dictates the deflection angle when the tunable function is active.Importantly,our tunable coding metasurface exhibits robust performance across a broad wavelength spectrum.The incorporation of high refractive-index liquid extends the regulatory dimension of the metadevice,enabling dynamic switching of encoding bit levels.This two-level tunable metadevice,rooted in phase-change materials,presents a promising avenue for the dynamic control of functions. 展开更多
关键词 coding metasurface tunable control phase change material electromagnetic wave manipulation
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Adoption of network and plan-do-check-action in the international classification of disease 10 coding
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作者 Biao Lian 《World Journal of Clinical Cases》 SCIE 2024年第19期3734-3743,共10页
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 a... 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. 展开更多
关键词 Plan-do-check-action cycle management mode Computer network International classification of diseases tenth edition coding Accuracy
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Adaptive Hybrid Forward Error Correction Coding Scheme for Video Transmission
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作者 XIONG Yuhui LIU Zhilong +4 位作者 XU Lingmin HUA Xinhai WANG Zhaoyang BI Ting JIANG Tao 《ZTE Communications》 2024年第2期85-93,共9页
This paper proposes an adaptive hybrid forward error correction(AH-FEC)coding scheme for coping with dynamic packet loss events in video and audio transmission.Specifically,the proposed scheme consists of a hybrid Ree... This paper proposes an adaptive hybrid forward error correction(AH-FEC)coding scheme for coping with dynamic packet loss events in video and audio transmission.Specifically,the proposed scheme consists of a hybrid Reed-Solomon and low-density parity-check(RS-LDPC)coding system,combined with a Kalman filter-based adaptive algorithm.The hybrid RS-LDPC coding accommodates a wide range of code length requirements,employing RS coding for short codes and LDPC coding for medium-long codes.We delimit the short and medium-length codes by coding performance so that both codes remain in the optimal region.Additionally,a Kalman filter-based adaptive algorithm has been developed to handle dynamic alterations in a packet loss rate.The Kalman filter estimates packet loss rate utilizing observation data and system models,and then we establish the redundancy decision module through receiver feedback.As a result,the lost packets can be perfectly recovered by the receiver based on the redundant packets.Experimental results show that the proposed method enhances the decoding performance significantly under the same redundancy and channel packet loss. 展开更多
关键词 video transmission packet loss Reed-Solomon code Kalman filter
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Recent Advances in Video Coding for Machines Standard and Technologies
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作者 ZHANG Qiang MEI Junjun +3 位作者 GUAN Tao SUN Zhewen ZHANG Zixiang YU Li 《ZTE Communications》 2024年第1期62-76,共15页
To improve the performance of video compression for machine vision analysis tasks,a video coding for machines(VCM)standard working group was established to promote standardization procedures.In this paper,recent advan... To improve the performance of video compression for machine vision analysis tasks,a video coding for machines(VCM)standard working group was established to promote standardization procedures.In this paper,recent advances in video coding for machine standards are presented and comprehensive introductions to the use cases,requirements,evaluation frameworks and corresponding metrics of the VCM standard are given.Then the existing methods are presented,introducing the existing proposals by category and the research progress of the latest VCM conference.Finally,we give conclusions. 展开更多
关键词 video coding for machines VCM video compression
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Index modulation aided generalized space-time block coding:A unified MIMO framework
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作者 Zhiqin Wang Hui Liu +3 位作者 Lixia Xiao Liuke Li Guochao Song Tao Jiang 《Digital Communications and Networks》 CSCD 2024年第5期1459-1470,共12页
In this paper,Index Modulation(IM)aided Generalized Space-Time Block Coding(GSTBC)is proposed,which intrinsically exploits the benefits of IM concept,diversity gain and spatial multiplexing gain.Specifically,the infor... In this paper,Index Modulation(IM)aided Generalized Space-Time Block Coding(GSTBC)is proposed,which intrinsically exploits the benefits of IM concept,diversity gain and spatial multiplexing gain.Specifically,the information bits are partitioned into U groups,with each being modulated by IM symbols(i.e.Spatial Modulation(SM),Quadrature SM(QSM),etc).Next,the structure of GSTBC is invoked for each K IM symbol,and a total ofμ=U/K GSTBC codes are transmitted via T time slots.A Block Expectation Propagation(B-EP)detector is designed for the proposed IM-GSTBC structure.Moreover,the theoretical Average Bit Error Probability(ABEP)is derived for our IM-GSTBC system,which is confirmed by the simulation results and helpful for performance evaluation.Simulation results show that our proposed IM-GSTBC system is capable of striking an efficient trade-off between spatial multiplexing gain,spatial diversity gain as well as implementation cost imposed for both small-scale and large-scale MIMO antenna configurations. 展开更多
关键词 Index modulation(IM) Generalized space time block coding(GSTBC) Spatial multiplexing gain Diversity gain Block expectation propagation(B-EP)
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Research on Big Data Coding System Based on the Classification of Artificial Materials and Mechanical Equipment in Construction Engineering
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作者 Zuguo Bai Sheng Han +1 位作者 Zhan Wei Jinping Chu 《Journal of Architectural Research and Development》 2024年第6期40-50,共11页
By analyzing and comparing the current application status and advantages and disadvantages of domestic and foreign artificial material mechanical equipment classification coding systems,and conducting a comparative st... By analyzing and comparing the current application status and advantages and disadvantages of domestic and foreign artificial material mechanical equipment classification coding systems,and conducting a comparative study of the existing coding system standards in different regions of the country,a coding data model suitable for big data research needs is proposed based on the current national standard for artificial material mechanical equipment classification coding.This model achieves a horizontal connection of characteristics and a vertical penetration of attribute values for construction materials and machinery through forward automatic coding calculation and reverse automatic decoding.This coding scheme and calculation model can also establish a database file for the coding and unit price of construction materials and machinery,forming a complete big data model for construction material coding unit prices.This provides foundational support for calculating and analyzing big data related to construction material unit prices,real-time information prices,market prices,and various comprehensive prices,thus contributing to the formation of cost-related big data. 展开更多
关键词 Data of labor MATERIALS EQUIPMENT CLASSIFICATION Big data coding system
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伪码调相连续波雷达微弱机动目标高精度参数估计方法
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作者 崔嵬 邢天乐 +1 位作者 金小萍 吴爽 《信号处理》 北大核心 2025年第1期31-42,共12页
伪码调相连续波雷达具有探测距离远、测量精度高、抗干扰能力强等优势,是天基雷达空间目标探测的重要手段。本文针对高速伪码调相连续波雷达对远距、机动目标的高精度参数估计问题,提出了一种基于跟踪环路的机动目标参数高精度估计算法... 伪码调相连续波雷达具有探测距离远、测量精度高、抗干扰能力强等优势,是天基雷达空间目标探测的重要手段。本文针对高速伪码调相连续波雷达对远距、机动目标的高精度参数估计问题,提出了一种基于跟踪环路的机动目标参数高精度估计算法。该算法首先利用分数阶傅里叶变换获得载波多普勒频率初始值和多普勒频率变化率的估计,并构造对数据跳变不敏感的相干载波提取环路,实现对伪码调相信号中载波参数的鲁棒提取与精确跟踪,从而得到高精度的相对速度估计结果;之后,利用载波多普勒频率估计结果“修正”本地发射伪码,消除伪码相位偏移。在通过相关处理得到伪码相位初始估计后,构造载波辅助相干伪码跟踪环路,实现对伪码相位的精确跟踪,从而获得高精度的相对距离估计结果。所提算法利用参数跟踪环路实时动态匹配的优点,解决了机动目标回波信号伪码相位偏移和多普勒扩展引入的积累效能降低和检测性能恶化问题,有效提高了机动目标参数估计精度。与部分相关-分数阶傅里叶变换、广义拉登傅里叶变换方法、迭代相邻相关运算方法相比,所提算法将机动目标多维参数搜索与匹配问题转化为两次一维参数精确提取问题,在获得机动目标相对距离、相对速度高精度估计的同时,有效降低了算法的运算量,为航天器空间平台资源强约束下实现自主探测感知提供了一种可行思路。 展开更多
关键词 伪码调相连续波雷达 机动目标 相干载波提取 伪码跟踪 参数估计
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基于二维码识别的分拣机械臂控制系统设计
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作者 关静丽 侯明 柏森 《机床与液压》 北大核心 2025年第3期60-65,共6页
为了提高物流行业自动化水平,提高物料分拣的工作效率、减少人工成本,设计基于二维码识别的分拣机械臂控制系统。以树莓派为主控制器,通过OpenCV图像处理、二维码识别、逆运动学求解和六自由度机械臂驱动等环节,实现了根据二维码存储的... 为了提高物流行业自动化水平,提高物料分拣的工作效率、减少人工成本,设计基于二维码识别的分拣机械臂控制系统。以树莓派为主控制器,通过OpenCV图像处理、二维码识别、逆运动学求解和六自由度机械臂驱动等环节,实现了根据二维码存储的信息进行物料分拣。为了提高二维码识别的准确率,针对二维码图像的磨损、划痕等问题,利用OpenCV对图像进行灰度化、滤波、二值化和闭运算等图像预处理操作;针对二维码位置的随机性和镜头畸变问题,通过定位算法和透视矫正提取出二维码,再根据QR码结构和编码规则进行二维码译码。为了使机械臂平滑稳定运行,采用简洁的几何法进行逆运动学的计算,并在机械臂驱动中加入多路舵机速度控制。实验结果表明:对于正常和有轻微划痕的二维码,二维码识别率可以达到100%,机械臂能够有效完成自动分拣任务,具有一定的实用价值。 展开更多
关键词 分拣机械臂 树莓派 二维码 OPENCV
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基于医保分类编码的医用耗材编码体系研究
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作者 陶敏 张晓雷 《医疗卫生装备》 2025年第1期83-87,共5页
介绍了现行医用耗材编码管理现状,基于医保分类编码并结合医院管理工作的实际需求建立了医用耗材编码体系,使分类标准明确、科学、统一,为公立医院医用耗材管理工作提供了具有可操作性的分类编码方法和思路。
关键词 医保分类编码 医用耗材编码 编码体系 医用耗材 医用耗材管理
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外泌体来源非编码RNA对骨关节炎微环境的作用及临床应用进展
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作者 李志超 杨振国 +4 位作者 王磊 王文波 薛景才 刘文斌 曹慧 《中国组织工程研究》 CAS 北大核心 2025年第13期2784-2792,共9页
背景:骨关节炎是一种常见的关节退行性疾病,其发生发展的病因学机制尚不清楚。早期骨关节炎的及时诊治十分重要,目前尚无确切有效的方法。外泌体来源广泛,其中包含非编码RNA(Non-coding RNAs,ncRNAs),如微小RNAs、环状RNAs和长链非编码R... 背景:骨关节炎是一种常见的关节退行性疾病,其发生发展的病因学机制尚不清楚。早期骨关节炎的及时诊治十分重要,目前尚无确切有效的方法。外泌体来源广泛,其中包含非编码RNA(Non-coding RNAs,ncRNAs),如微小RNAs、环状RNAs和长链非编码RNAs。外泌体ncRNAs可直接从原始细胞递送至邻近或远程细胞,通过细胞间通讯调节细胞活性,在重塑骨关节微环境中具有重要的调控作用。目的:总结外泌体来源ncRNAs对骨关节炎关节内微环境的干预作用,以及在临床应用中取得的进展,阐明其在骨关节炎诊治方面的潜力。方法:以“exosomes,non-coding RNA,osteoarthritis,application,signal pathway,synovial fluid,cartilage cells,cartilage matrix,subchondral bone,mechanism”为检索词在PubMed数据库中进行检索,最终纳入66篇相关文献进行综述分析。结果与结论:①外泌体来源ncRNAs在骨关节炎的发病过程中对关节内微环境具有重要调控作用,主要体现在外泌体ncRNAs调控关节内炎症反应、软骨细胞及软骨基质的退化,软骨下骨重塑和细胞间通讯。②外泌体中的ncRNAs可以作为骨关节炎的生物标志物,帮助骨关节炎的早期诊断和监测疾病进展与预后。③外泌体ncRNAs可作为骨关节炎的治疗靶点,外泌体携带miRNAs递送到关节的软骨细胞及软骨基质,发挥调控作用。④外泌体ncRNAs可以通过调控基因表达、促进细胞间通讯,提高软骨组织工程的效果,修复或再生受损软骨。⑤未来研究者应继续发掘外泌体来源ncRNAs对骨关节炎的干预机制,并可结合最新软骨组织工程的研究成果应用到临床之中,这将有效帮助解决骨关节炎患者的病痛。 展开更多
关键词 外泌体 非编码RNA 骨关节炎 关节内微环境 信号通路 软骨退变 生物标志物 临床应用
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肾病综合征病人血清lncRNA ANRIL和BDNF水平变化与血栓栓塞的相关性分析
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作者 顾玉 梁晓艳 +2 位作者 马胜辉 佟娜 阎泽君 《安徽医药》 CAS 2025年第1期141-146,共6页
目的探究肾病综合征(NS)病人血清长链非编码RNA(lncRNA)细胞周期激酶抑制因子4基因座中反义非编码RNA(ANRIL)和脑源性神经营养因子(BDNF)水平变化与血栓栓塞(TE)的相关性。方法选取2019年3月至2021年12月在承德市中心医院住院治疗的220... 目的探究肾病综合征(NS)病人血清长链非编码RNA(lncRNA)细胞周期激酶抑制因子4基因座中反义非编码RNA(ANRIL)和脑源性神经营养因子(BDNF)水平变化与血栓栓塞(TE)的相关性。方法选取2019年3月至2021年12月在承德市中心医院住院治疗的220例NS病人为研究对象,根据随访结果将其分为NS组118例和TE组102例,另外选取同期体检健康者100例为对照组。采用实时荧光定量PCR(qRT-PCR)测定研究对象血清lncRNA ANRIL水平;采用酶联免疫吸附测定(ELISA)检测研究对象血清BDNF水平;使用全自动生化分析仪检测相关生化指标;采用Pearson相关性分析血清lncRNA ANRIL、BDNF水平与生化指标相关性;采用多因素logistic回归分析NS病人发生TE的影响因素;采用受试者操作特征曲线(ROC曲线)分析血清lncRNA ANRIL、BDNF在预测NS病人发生TE中的价值。结果与对照组相比较,NS组、TE组血清lncRNA ANRIL水平显著升高(2.54±0.43比5.82±1.34、8.35±2.17),BDNF水平显著降低[(32.77±8.25)μg/L比(24.49±4.58)μg/L、(18.63±3.62)μg/L](P<0.05);与NS组相比较,TE组血清lncRNA ANRIL水平显著升高,BDNF水平显著降低(P<0.05);对照组、NS组、TE组三组的尿酸、血肌酐、乳酸脱氢酶、血尿素氮、尿蛋白水平呈逐渐升高趋势,血清白蛋白、血红蛋白水平呈逐渐降低趋势(P<0.05)。Pearson相关性分析显示,NS合并TE病人血清lncRNA ANRIL水平与尿酸、血肌酐、乳酸脱氢酶、血尿素氮、尿蛋白水平呈正相关,与血清白蛋白、血红蛋白水平呈负相关(P<0.05);NS合并TE病人血清BDNF水平与尿酸、血肌酐、乳酸脱氢酶、血尿素氮、尿蛋白水平呈负相关,与血清白蛋白、血红蛋白水平呈正相关(P<0.05)。多因素logistic回归分析显示,lncRNA ANRIL、尿蛋白和BDNF是NS病人发生TE的影响因素(P<0.05);ROC曲线结果显示,血清lncRNA ANRIL、BDNF预测NS病人发生TE的曲线下面积(AUC)分别为0.84、0.85,两者联合预测的AUC为0.92,高于lncRNA ANRIL、BDNF单独检测,特异度为83.05%,灵敏度为88.24%。结论NS伴TE病人中血清lncRNA ANRIL水平升高,BDNF水平降低,二者对NS病人发生TE具有一定的预测价值。 展开更多
关键词 肾病综合征 非编码RNA ANRIL 脑源性神经营养因子 血栓栓塞 预测价值
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