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Effects of Acetic Acid Bacteria (Gluconacetobacter hansenii GK-1) on Fatigue Induced by Temporary Mental Stress: A Randomized, Double-Blind, Placebo-Controlled Study
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作者 Wei Wang Mariko Oe +6 位作者 Mengwei Yuan Keiko Kuriyama Yumi Takeda Mamoru Kimura Ryosuke Matsuoka Kiichi Sugiyama Naoki Miura 《Food and Nutrition Sciences》 2025年第1期44-54,共11页
Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placeb... Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placebo-controlled, parallel-group study included 100 healthy male and female adults aged 20 - 64 years. Participants consumed either the G. hansenii GK-1 supplement (9 × 10⁹ cells/day) or a placebo daily for 12 weeks. The impact of temporary mental stress on fatigue in G. hansenii GK-1 was assessed using a Visual Analog Scale (VAS) before the study began and after 12 weeks of supplementation. Results: Subjective fatigue measured by Visual Analog Scale (VAS) showed a significant decrease in fatigue induced by temporary mental stress after 12 weeks of consumption in the G. hansenii GK-1 group compared with the placebo group. No adverse events were attributed to G. hansenii GK-1. These findings confirm that continuous oral ingestion of G. hansenii GK-1 by healthy Japanese adults reduces feelings of fatigue caused by temporary mental stress. 展开更多
关键词 Acetic Acid Bacteria Gluconacetobacter hansenii GK-1 FATIGUE Temporary Mental Stress Double-blind Study
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A Blind Batch Encryption and Public Ledger-Based Protocol for Sharing Sensitive Data 被引量:1
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作者 Zhiwei Wang Nianhua Yang +2 位作者 Qingqing Chen Wei Shen Zhiying Zhang 《China Communications》 SCIE CSCD 2024年第1期310-322,共13页
For the goals of security and privacy preservation,we propose a blind batch encryption-and public ledger-based data sharing protocol that allows the integrity of sensitive data to be audited by a public ledger and all... For the goals of security and privacy preservation,we propose a blind batch encryption-and public ledger-based data sharing protocol that allows the integrity of sensitive data to be audited by a public ledger and allows privacy information to be preserved.Data owners can tightly manage their data with efficient revocation and only grant one-time adaptive access for the fulfillment of the requester.We prove that our protocol is semanticallly secure,blind,and secure against oblivious requesters and malicious file keepers.We also provide security analysis in the context of four typical attacks. 展开更多
关键词 blind batch encryption data sharing onetime adaptive access public ledger security and privacy
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For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology 被引量:1
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作者 Chengjie Li Lidong Zhu Zhen Zhang 《China Communications》 SCIE CSCD 2024年第2期85-95,共11页
In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signal... In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system. 展开更多
关键词 blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction
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Countermeasure against blinding attack for single-photon detectors in quantum key distribution
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作者 Lianjun Jiang Dongdong Li +12 位作者 Yuqiang Fang Meisheng Zhao Ming Liu Zhilin Xie Yukang Zhao Yanlin Tang Wei Jiang Houlin Fang Rui Ma Lei Cheng Weifeng Yang Songtao Han Shibiao Tang 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期76-81,共6页
Quantum key distribution(QKD),rooted in quantum mechanics,offers information-theoretic security.However,practi-cal systems open security threats due to imperfections,notably bright-light blinding attacks targeting sin... Quantum key distribution(QKD),rooted in quantum mechanics,offers information-theoretic security.However,practi-cal systems open security threats due to imperfections,notably bright-light blinding attacks targeting single-photon detectors.Here,we propose a concise,robust defense strategy for protecting single-photon detectors in QKD systems against blinding attacks.Our strategy uses a dual approach:detecting the bias current of the avalanche photodiode(APD)to defend against con-tinuous-wave blinding attacks,and monitoring the avalanche amplitude to protect against pulsed blinding attacks.By integrat-ing these two branches,the proposed solution effectively identifies and mitigates a wide range of bright light injection attempts,significantly enhancing the resilience of QKD systems against various bright-light blinding attacks.This method forti-fies the safeguards of quantum communications and offers a crucial contribution to the field of quantum information security. 展开更多
关键词 quantum key distribution single photon detector blinding attack pulsed blinding attack COUNTERMEASURE quan-tum communication
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Blind Recognition of Non-Binary LDPC Codes Based on Ant Colony Optimization
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作者 Guan Mengsheng Gao Wanting +2 位作者 Chen Qi Zhu Min Bai Baoming 《China Communications》 SCIE CSCD 2024年第10期59-69,共11页
This paper introduces a novel blind recognition of non-binary low-density parity-check(LDPC)codes without a candidate set,using ant colony optimization(ACO)algorithm over additive white Gaussian noise(AWGN)channels.Sp... This paper introduces a novel blind recognition of non-binary low-density parity-check(LDPC)codes without a candidate set,using ant colony optimization(ACO)algorithm over additive white Gaussian noise(AWGN)channels.Specifically,the scheme that effectively combines the ACO algorithm and the non-binary elements over finite fields is proposed.Furthermore,an improved,simplified elitist ACO algorithm based on soft decision reliability is introduced to recognize the parity-check matrix over noisy channels.Simulation results show that the recognition rate continuously increases with an increased signalto-noise ratio(SNR)over the AWGN channel. 展开更多
关键词 ACO blind recognition non-binary LDPC codes open-set
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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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Quantum circuit-based proxy blind signatures:A novel approach and experimental evaluation on the IBM quantum cloud platform
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作者 娄小平 昝慧茹 徐雪娇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期247-253,共7页
This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a... This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive information.The main objective of this research is to introduce a quantum proxy blind signature(QPBS)protocol that utilizes quantum logical gates and quantum measurement techniques.The QPBS protocol is constructed by the initial phase,proximal blinding message phase,remote authorization and signature phase,remote validation,and de-blinding phase.This innovative design ensures a secure mechanism for signing documents without revealing the content to the proxy signer,providing practical security authentication in a quantum environment under the assumption that the CNOT gates are securely implemented.Unlike existing approaches,our proposed QPBS protocol eliminates the need for quantum entanglement preparation,thus simplifying the implementation process.To assess the effectiveness and robustness of the QPBS protocol,we conduct comprehensive simulation studies in both ideal and noisy quantum environments on the IBM quantum cloud platform.The results demonstrate the superior performance of the QPBS algorithm,highlighting its resilience against repudiation and forgeability,which are key security concerns in the realm of proxy blind signatures.Furthermore,we have established authentic security thresholds(82.102%)in the presence of real noise,thereby emphasizing the practicality of our proposed solution. 展开更多
关键词 proxy blind signature quantum circuits quantum computation IBM quantum cloud platform
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Robust blind image watermarking based on interest points
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作者 Zizhuo WANG Kun HU +3 位作者 Chaoyangfan HUANG Zixuan HU Shuo YANG Xingjun WANG 《虚拟现实与智能硬件(中英文)》 EI 2024年第4期308-322,共15页
Digital watermarking technology plays an essential role in the work of anti-counterfeiting and traceability.However,image watermarking algorithms are weak against hybrid attacks,especially geometric attacks,such as cr... Digital watermarking technology plays an essential role in the work of anti-counterfeiting and traceability.However,image watermarking algorithms are weak against hybrid attacks,especially geometric attacks,such as cropping attacks,rotation attacks,etc.We propose a robust blind image watermarking algorithm that combines stable interest points and deep learning networks to improve the robustness of the watermarking algorithm further.First,to extract more sparse and stable interest points,we use the Superpoint algorithm for generation and design two steps to perform the screening procedure.We first keep the points with the highest possibility in a given region to ensure the sparsity of the points and then filter the robust interest points by hybrid attacks to ensure high stability.The message is embedded in sub-blocks centered on stable interest points using a deep learning-based framework.Different kinds of attacks and simulated noise are added to the adversarial training to guarantee the robustness of embedded blocks.We use the ConvNext network for watermark extraction and determine the division threshold based on the decoded values of the unembedded sub-blocks.Through extensive experimental results,we demonstrate that our proposed algorithm can improve the accuracy of the network in extracting information while ensuring high invisibility between the embedded image and the original cover image.Comparison with previous SOTA work reveals that our algorithm can achieve better visual and numerical results on hybrid and geometric attacks. 展开更多
关键词 blind watermarking Robust region selection Geometric distortion Deep learning
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Blind radar signal separation algorithm based on third-order degree of cyclostationarity criteria
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作者 FAN Xiangyu LIU Bin +2 位作者 DONG Danna CHEN You WANG Yuancheng 《Journal of Systems Engineering and Electronics》 CSCD 2024年第6期1441-1453,共13页
Separation and recognition of radar signals is the key function of modern radar reconnaissance,which is of great sig-nificance for electronic countermeasures and anti-countermea-sures.In order to improve the ability o... Separation and recognition of radar signals is the key function of modern radar reconnaissance,which is of great sig-nificance for electronic countermeasures and anti-countermea-sures.In order to improve the ability of separating mixed signals in complex electromagnetic environment,a blind source separa-tion algorithm based on degree of cyclostationarity(DCS)crite-rion is constructed in this paper.Firstly,the DCS criterion is con-structed by using the cyclic spectrum theory.Then the algo-rithm flow of blind source separation is designed based on DCS criterion.At the same time,Givens matrix is constructed to make the blind source separation algorithm suitable for multiple sig-nals with different cyclostationary frequencies.The feasibility of this method is further proved.The theoretical and simulation results show that the algorithm can effectively separate and re-cognize common multi-radar signals. 展开更多
关键词 blind signal separation cyclostationary frequency Givens matrix degree of cyclostationarity(DCS)blind source separation algorithm
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Research on blind source separation of operation sounds of metro power transformer through an Adaptive Threshold REPET algorithm
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作者 Liang Chen Liyi Xiong +2 位作者 Fang Zhao Yanfei Ju An Jin 《Railway Sciences》 2024年第5期609-621,共13页
Purpose–The safe operation of the metro power transformer directly relates to the safety and efficiency of the entire metro system.Through voiceprint technology,the sounds emitted by the transformer can be monitored ... Purpose–The safe operation of the metro power transformer directly relates to the safety and efficiency of the entire metro system.Through voiceprint technology,the sounds emitted by the transformer can be monitored in real-time,thereby achieving real-time monitoring of the transformer’s operational status.However,the environment surrounding power transformers is filled with various interfering sounds that intertwine with both the normal operational voiceprints and faulty voiceprints of the transformer,severely impacting the accuracy and reliability of voiceprint identification.Therefore,effective preprocessing steps are required to identify and separate the sound signals of transformer operation,which is a prerequisite for subsequent analysis.Design/methodology/approach–This paper proposes an Adaptive Threshold Repeating Pattern Extraction Technique(REPET)algorithm to separate and denoise the transformer operation sound signals.By analyzing the Short-Time Fourier Transform(STFT)amplitude spectrum,the algorithm identifies and utilizes the repeating periodic structures within the signal to automatically adjust the threshold,effectively distinguishing and extracting stable background signals from transient foreground events.The REPET algorithm first calculates the autocorrelation matrix of the signal to determine the repeating period,then constructs a repeating segment model.Through comparison with the amplitude spectrum of the original signal,repeating patterns are extracted and a soft time-frequency mask is generated.Findings–After adaptive thresholding processing,the target signal is separated.Experiments conducted on mixed sounds to separate background sounds from foreground sounds using this algorithm and comparing the results with those obtained using the FastICA algorithm demonstrate that the Adaptive Threshold REPET method achieves good separation effects.Originality/value–A REPET method with adaptive threshold is proposed,which adopts the dynamic threshold adjustment mechanism,adaptively calculates the threshold for blind source separation and improves the adaptability and robustness of the algorithm to the statistical characteristics of the signal.It also lays the foundation for transformer fault detection based on acoustic fingerprinting. 展开更多
关键词 TRANSFORMER Voiceprint recognition blind source separation Mel frequency cepstral coefficients(MFCC) Adaptive threshold
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Exploring the meaning of care among lived experiences of patients with blindness:an interpretive phenomenological study
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作者 Mohammad Ali Mohammadi Mehdi Heidarzadeh +1 位作者 Saeed Mehri Mahmood Shamshiri 《Frontiers of Nursing》 2024年第3期319-326,共8页
Objective:To explore the meaning of care experienced by people with blindness in hospitals.Methods:Interpretive phenomenology along with the 6-step method of van Manen was used to conduct the study.Using purposeful sa... Objective:To explore the meaning of care experienced by people with blindness in hospitals.Methods:Interpretive phenomenology along with the 6-step method of van Manen was used to conduct the study.Using purposeful sampling,15 people with legal blindness were interviewed.Thematic analysis was used to isolate the meaning of care.Results:Five themes emerged:(a)nurses in the eyes of patients with blindness;(b)negligence in the caring moments;(c)being cared for in ambiguity;(d)Uncoordinated care;and(e)Psychological discomfor t.These sub-themes were condensed into an overarching theme titled as“marginalized patients inside the stereotypical healthcare system.”Conclusions:Lived experiences of patients with blindness revealed that hospitals provide stereotypic or inappropriate care for this minority group in society.Health professionals par ticularly nurses should be skilled to provide person-centered and coordinated care for patients with blindness. 展开更多
关键词 HOSPITALIZATION lived experience meaning of care people with blindness PHENOMENOLOGY
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结合SM9和盲签名的联盟链交易隐私保护方案 被引量:1
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作者 邵清 张磊军 《小型微型计算机系统》 北大核心 2025年第1期217-224,共8页
为了解决联盟链应用场景中交易数据存在的隐私泄露问题,本文提出了一种结合SM9标识密码算法和盲签名的联盟链交易隐私保护方案.一方面,引入布隆过滤器对密钥生成中心(KGC)生成的密钥进行唯一性验证,解决密钥可能重复的问题.另一方面,在... 为了解决联盟链应用场景中交易数据存在的隐私泄露问题,本文提出了一种结合SM9标识密码算法和盲签名的联盟链交易隐私保护方案.一方面,引入布隆过滤器对密钥生成中心(KGC)生成的密钥进行唯一性验证,解决密钥可能重复的问题.另一方面,在SM9标识密码算法中引入了盲签名机制,增强交易的隐私性.通过方案对比证明该方案的效率有所提高:在签名阶段比杨等人的方案减少了1次群内点乘操作,在验签阶段比刁等人的方案减少了近2次双线性配对操作.仿真实验发现布隆过滤器对私钥生成过程的耗时影响微乎其微.本方案在效率和隐私保护方面实现了良好的平衡,在需要身份可溯源、但又要求交易内容匿名的场景具有一定的价值. 展开更多
关键词 SM9算法 盲签名 联盟链 布隆过滤器 隐私保护
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基于DDPM的盲解调实验系统设计
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作者 臧淼 邢志强 李响 《实验室研究与探索》 北大核心 2025年第1期91-95,170,共6页
盲解调技术因其在非协作通信领域的重要应用而广受关注,因其理论的抽象、复杂性成为课程教学中的一个难点。基于Matlab设计一套非协作通信环境下的盲解调系统。系统涵盖载波频率估计、符号速率估计、调制方式识别、载波同步、符号同步... 盲解调技术因其在非协作通信领域的重要应用而广受关注,因其理论的抽象、复杂性成为课程教学中的一个难点。基于Matlab设计一套非协作通信环境下的盲解调系统。系统涵盖载波频率估计、符号速率估计、调制方式识别、载波同步、符号同步以及盲均衡等多个模块。通过采用去噪扩散概率模型(DDPM)对调制信号星座图样点去噪,基于最小均方误差自动识别多进制相移键控的调制方式。实验结果表明,该盲解调系统能有效估计信号参数、提取信号星座图和识别调制方式,成功解调还原信号,并保持较低的误码率。该系统具有较强的综合性、直观性和可扩展性,有利于学生理解盲解调系统的工作原理和DDPM的应用场景,培养学生的工程实践能力和创新思维。 展开更多
关键词 去噪扩散概率模型 盲解调 星座图 调制方式识别
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刮痧联合刺络拔罐对稳定期慢性阻塞性肺疾病患者症状及未来风险的影响
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作者 张虹 苏景深 +5 位作者 马兆润 刘臣超 冯李婷 张凤超 陈瑞雪 苏东岳 《天津中医药》 2025年第3期289-296,共8页
[目的]评价刮痧联合刺络拔罐对稳定期慢性阻塞性肺疾病(COPD)患者症状及未来风险的影响。[方法]将2021年12月1日—2023年12月31日期间招募的120例稳定期COPD患者随机分为刮痧刺络拔罐组、刮痧组、对照组,每组各40例。刮痧刺络拔罐组给... [目的]评价刮痧联合刺络拔罐对稳定期慢性阻塞性肺疾病(COPD)患者症状及未来风险的影响。[方法]将2021年12月1日—2023年12月31日期间招募的120例稳定期COPD患者随机分为刮痧刺络拔罐组、刮痧组、对照组,每组各40例。刮痧刺络拔罐组给予循经刮痧联合刺络拔罐。刮痧组给予循经刮痧,对照组给予假刮痧。整个治疗期共2个疗程(农历三九和农历三伏),含刮痧(假刮痧)8次,刺络拔罐治疗24次。随访期6个月。治疗前后、随访时,记录患者肺功能(PFT)指标,包括用力第1秒呼气量(FEV_(1)%)和1 s用力呼气容积与用力肺活量的比值(FEV_(1)/FVC%),动脉氧分压(PaO_(2))和动脉二氧化碳分压(PaCO_(2)),圣乔治呼吸问卷(SGRQ)评分,6 min步行试验距离(6MWD),急性加重事件次数。评估患者治疗前后、随访时各指标的变化。[结果]研究过程中,刮痧刺络拔罐组和刮痧组的PET、PaO_(2)、SGRQ评分数值均出现上升,3组在治疗前、治疗后、随访时3个时间点进行重复测量方差分析显示,以上指标的时间和组别之间的交互作用均有统计学意义(P<0.05)。组内比较显示,刮痧刺络拔罐组和刮痧组治疗后、随访时PET、PaO_(2)指标数值及SGRQ评分均较各自治疗前提高(P<0.05)。组间比较显示,刮痧刺络拔罐组和刮痧组治疗后、随访时的PET指标及SGRQ评分比较,差异均无统计学意义(P>0.05),而治疗后、随访时的PaO_(2)比较,差异有统计学意义(P<0.05),且均高于对照组(P<0.05)。但3组PaCO_(2)的重复测量方差分析显示,时间和组别之间的交互作用差异无统计学意义(P>0.05),组内和组间比较显示差异无统计学意义(P>0.05)。[结论]刮痧刺络拔罐、刮痧均能够有效改善稳定期COPD的气流受限,提高动脉氧含量,增加心肺耐力,提高生活质量,降低急性加重事件次数,具有后治疗效应。两种疗法在改善气流受限、提高心肺耐力,提高生活质量,降低未来加重风险方面作用基本一致,且均不能改善CO_(2)潴留状态。但刮痧刺络拔罐比刮痧更能够显著提高血氧含量。 展开更多
关键词 刮痧 刺络拔罐 COPD 单盲 随机对照试验
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开盲盒式微波技术基础课程系列测量实验方案设计
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作者 王亚飞 李学华 +1 位作者 张兰杰 赵彦晓 《实验科学与技术》 2025年第2期1-6,共6页
微波测量是微波工程中的重要环节,为了培养学生微波测量的实践能力和工程应用能力,在微波技术基础课程中设计了开盲盒式微波测量“探究性—验证性”系列实验。开盲盒式微波测量系列实验以测量驻波比、负载阻抗、二端口网络S参量等为内容... 微波测量是微波工程中的重要环节,为了培养学生微波测量的实践能力和工程应用能力,在微波技术基础课程中设计了开盲盒式微波测量“探究性—验证性”系列实验。开盲盒式微波测量系列实验以测量驻波比、负载阻抗、二端口网络S参量等为内容,在同一个测量实验中,设置多个测量对象但不给出测量对象的基本指标,以开盲盒的方式测量微波器件,增加了实验结果的不确定性。同时在测量对象中设置“隐藏款”,以锻炼与检验学生的微波工程实践能力和分析解决问题的能力,为学生进一步设计微波元件打下技术基础。 展开更多
关键词 微波技术 微波测量实验 盲盒 矢量网络分析仪
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基于K-PSO和StOMP的往复压缩机激振信号盲源分离
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作者 王金东 马智超 +2 位作者 赵海洋 李彦阳 张宇 《机床与液压》 北大核心 2025年第3期228-234,共7页
在当前信号的盲源分离中,传统“两步法”易陷入局部最优解,并且其准确率会随采集信号数的增加或稀疏性的降低而大幅下降。针对上述问题,提出一种结合K均值-粒子群(K-PSO)和分段正交匹配追踪(StOMP)的稀疏分量分析方法。对采集信号执行K... 在当前信号的盲源分离中,传统“两步法”易陷入局部最优解,并且其准确率会随采集信号数的增加或稀疏性的降低而大幅下降。针对上述问题,提出一种结合K均值-粒子群(K-PSO)和分段正交匹配追踪(StOMP)的稀疏分量分析方法。对采集信号执行K均值聚类算法,将产生的结果反馈至PSO聚类中估计混合矩阵。在获得混合矩阵后,将其源信号矩阵转化成列数为1的向量,再通过分段正交匹配追踪算法重构源信号。将实测的往复压缩机正常信号和3种单一故障信号混合成2种复合故障信号,并对复合故障信号进行试验验证。结果表明:在计算时间方面,相较模糊C均值聚类(0.335 s)和K均值聚类(0.299 s),尽管K-PSO聚类方法牺牲了一部分效率(1.561 s),但在总体角度偏差和归一化均方根误差方面表现更优,具有更好的估计精度;相较最短路径法(0.123 s),StOMP算法同样牺牲效率(2.031 s),却获得更佳的相关系数和均方根误差,表现更好的分离重构能力。这说明,该方法在盲源分离中具有可行性和实际应用价值。 展开更多
关键词 往复压缩机 欠定盲源分离 K均值聚类 粒子群算法 分段正交匹配追踪
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数字图像水印综述
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作者 赵学军 曹天宇 李琳 《工业控制计算机》 2025年第1期108-110,共3页
随着数字化时代的到来,数字媒体信息的传播和复制变得非常容易,数字内容的版权问题越来越严重。为解决这一问题,数字水印技术应运而生,将信息嵌入到数字内容中,从而保护数字版权。将对数字水印技术的概念、分类、特点、应用及发展进行... 随着数字化时代的到来,数字媒体信息的传播和复制变得非常容易,数字内容的版权问题越来越严重。为解决这一问题,数字水印技术应运而生,将信息嵌入到数字内容中,从而保护数字版权。将对数字水印技术的概念、分类、特点、应用及发展进行全面的综述,首先,总结了数字水印当前的技术特点,并进行分类;其次,介绍了数字水印的特点以及评价指标;然后,介绍了目前对水印的攻击方式以及数字水印的应用;最后,提出了数字水印的不足及未来发展趋势。 展开更多
关键词 数字水印 数字图像 鲁棒性 盲水印 脆弱水印
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X80高钢级管道焊接残余应力测试研究
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作者 古松 蒋广 +3 位作者 顾颖 陈祥斌 孔超 张豫 《精密成形工程》 北大核心 2025年第1期127-133,共7页
目的获得X80高钢级管道环焊缝焊接残余应力大小与分布模式。方法首先采用盲孔法对X80高钢级管道的环焊缝焊接残余应力进行了测试,然后将测试结果与X80管道焊接残余应力的相关文献试验数据以及国家标准《在用含缺陷压力容器安全评定》GB/... 目的获得X80高钢级管道环焊缝焊接残余应力大小与分布模式。方法首先采用盲孔法对X80高钢级管道的环焊缝焊接残余应力进行了测试,然后将测试结果与X80管道焊接残余应力的相关文献试验数据以及国家标准《在用含缺陷压力容器安全评定》GB/T 19624—2019所规定的内容进行了对比分析,最后根据测试数据提出了X80高钢级管道环焊缝焊接残余应力σ_(R)与距焊缝中心距离x之间的函数关系式,进一步得到了X80管道环焊缝沿环向与轴向的焊接残余应力计算公式。结果X80管道环焊缝沿环向区域存在较大的残余拉应力,焊接残余应力在焊趾区域达到峰值,表现为随着距焊缝中心距离的增加,环向残余应力由拉应力小幅度增加达到峰值567 MPa后迅速转变为压应力,随后缓慢转变为拉应力并趋近于0。随着距焊缝中心距离的增加,轴向残余应力由压应力迅速转变为拉应力,其中压应力峰值为92 MPa,发生在焊缝熔合线位置,拉应力峰值为188 MPa,出现在远离熔合线16 mm位置。结论根据试验结果提出了适用于X80管道环焊缝沿环向与轴向的焊接残余应力分布模式,为含缺陷X80管道的安全评定及修复提供理论参考。 展开更多
关键词 X80管道 焊接残余应力 盲孔法 环焊缝 试验研究
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一种基于Blind Kriging模型和差分进化的电磁结构优化算法 被引量:2
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作者 陈晓辉 郭欣欣 裴进明 《电子测量与仪器学报》 CSCD 北大核心 2016年第11期1694-1700,共7页
各类电磁结构日趋复杂,设计自由度不断提升.传统优化算法需要对大量的参数组合进行全波仿真试探,设计效率普遍较低。针对这一问题,提出BK(blind Kriging)模型和差分进化相结合的电磁结构优化算法.相比普通Kriging模型,BK模型通过贝叶斯... 各类电磁结构日趋复杂,设计自由度不断提升.传统优化算法需要对大量的参数组合进行全波仿真试探,设计效率普遍较低。针对这一问题,提出BK(blind Kriging)模型和差分进化相结合的电磁结构优化算法.相比普通Kriging模型,BK模型通过贝叶斯参数选择算法将影响性能的主要因子加入回归模型,提高对响应的预测精度;依据BK模型的预测结果从每代差分进化种群中选择最优个体执行电磁仿真。由于优化过程中大量的电磁计算转移到快速的BK模型,优化效率得到显著提升。通过一个圆波导多螺钉极化转换器的优化设计,表明该方法的求解质量和收敛速度优于现有算法。 展开更多
关键词 电磁结构 优化算法 blind KRIGING 差分进化
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一种基于新型级联结构的宽带非线性盲均衡算法
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作者 刘洋 《通信技术》 2025年第2期123-127,共5页
针对高速高动态宽带卫星信道中线性失真和非线性失真并存的问题,提出一种基于新型级联结构的宽带非线性盲均衡算法。算法通过构建一种线性与非线性级联的滤波器算法结构,以同时矫正宽带卫星信道带来的线性畸变和非线性畸变。为验证算法... 针对高速高动态宽带卫星信道中线性失真和非线性失真并存的问题,提出一种基于新型级联结构的宽带非线性盲均衡算法。算法通过构建一种线性与非线性级联的滤波器算法结构,以同时矫正宽带卫星信道带来的线性畸变和非线性畸变。为验证算法的有效性,在10 Gbit/s高速数传接收机平台进行了实验。实验结果表明,相比传统的线性均衡算法,该算法可以同时矫正信道的线性畸变和非线性畸变,工程应用价值高。 展开更多
关键词 卫星信道 线性失真 非线性失真 新型级联结构 宽带信号盲均衡
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