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Target intention prediction of air combat based on Mog-GRU-D network under incomplete information
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作者 CHEN Jun SUN Xiang +1 位作者 XUE Zhe ZHANG Xinyu 《Journal of Systems Engineering and Electronics》 2025年第4期972-984,共13页
High complexity and uncertainty of air combat pose significant challenges to target intention prediction.Current interpolation methods for data pre-processing and wrangling have limitations in capturing interrelations... High complexity and uncertainty of air combat pose significant challenges to target intention prediction.Current interpolation methods for data pre-processing and wrangling have limitations in capturing interrelationships among intricate variable patterns.Accordingly,this study proposes a Mogrifier gate recurrent unit-D(Mog-GRU-D)model to address the com-bat target intention prediction issue under the incomplete infor-mation condition.The proposed model directly processes miss-ing data while reducing the independence between inputs and output states.A total of 1200 samples from twelve continuous moments are captured through the combat simulation system,each of which consists of seven dimensional features.To bench-mark the experiment,a missing valued dataset has been gener-ated by randomly removing 20%of the original data.Extensive experiments demonstrate that the proposed model obtains the state-of-the-art performance with an accuracy of 73.25%when dealing with incomplete information.This study provides possi-ble interpretations for the principle of target interactive mecha-nism,highlighting the model’s effectiveness in potential air war-fare implementation. 展开更多
关键词 intention prediction incomplete information gate recurrent unit(GRU) Mogrifier interaction mechanism.
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多模式选择的OFDM索引调制传输方案
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作者 郭漪 朱煜晨 +2 位作者 王翊卿 刘刚 付少忠 《通信学报》 北大核心 2025年第1期23-34,共12页
针对基于索引调制的正交频分复用(OFDM-IM)技术在索引信息受限于载波激活模式数量和单一信号星座模式的问题,提出一种多模式选择的OFDM索引调制传输方案。该方案通过设计可区分的信号星座,使得模式组内和模式组间相邻星座点之间的欧氏... 针对基于索引调制的正交频分复用(OFDM-IM)技术在索引信息受限于载波激活模式数量和单一信号星座模式的问题,提出一种多模式选择的OFDM索引调制传输方案。该方案通过设计可区分的信号星座,使得模式组内和模式组间相邻星座点之间的欧氏距离相等,从而提升误码率。此外,通过在多模式选择索引调制的索引信息中引入全子载波激活模式,显著提升系统的频谱效率。同时,由于所提方案的子载波激活模式与二进制数字相匹配,系统能够采用低复杂度的对数似然比检测算法,并保持良好的误码率性能。理论分析与仿真结果表明,在加性白高斯噪声信道和瑞利衰落信道下,相较于OFDM-IM、OFDM-SSIM和MMS-OFDM-IM传输方案,所提方案有效提升了频谱效率且保持了良好的误码率。 展开更多
关键词 多模式选择 索引调制 正交频分复用 频谱效率 误码率
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基于多包络方法的3D双模OFDM-IM调制及其性能分析
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作者 郭漪 华朱昊 +1 位作者 刘刚 付少忠 《通信学报》 北大核心 2025年第5期159-166,共8页
针对当前高维OFDM索引调制系统误码率较高、抗干扰能力有限的问题,提出了一种基于多包络三维星座调制的双模正交频分复用索引调制(3D-DM-OFDM-IM)方案。该方案采用多个球体包络内接正多面体的方法来设计3D星座图,相比现有3D星座映射方案... 针对当前高维OFDM索引调制系统误码率较高、抗干扰能力有限的问题,提出了一种基于多包络三维星座调制的双模正交频分复用索引调制(3D-DM-OFDM-IM)方案。该方案采用多个球体包络内接正多面体的方法来设计3D星座图,相比现有3D星座映射方案,增大了星座点间的最小欧氏距离。仿真结果表明,在保证频谱效率相同的条件下,无论是低阶调制还是高阶调制,所提方案相比现有3D双模OFDM-IM调制方案,都具有更好的误码率性能和更低的峰均比。 展开更多
关键词 三维星座 索引调制 正交频分复用 频谱效率 误码率
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6DOF机器人末端加速度的数值求解及预测研究
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作者 林义忠 陈祯阳 +1 位作者 秦琦航 程辉煌 《机械设计与制造》 北大核心 2025年第4期362-366,共5页
针对多自由度机器人末端加速度的获取方法中,基于模型的加速度的传统求解方法存在计算过程复杂、实时性差的缺点,提出了一种基于机器人关节信息的末端加速度计算方法,使用机器人的关节位置与关节速度信息,结合机器人速度雅可比和差分法... 针对多自由度机器人末端加速度的获取方法中,基于模型的加速度的传统求解方法存在计算过程复杂、实时性差的缺点,提出了一种基于机器人关节信息的末端加速度计算方法,使用机器人的关节位置与关节速度信息,结合机器人速度雅可比和差分法得到机器人末端加速度。在求解加速度的基础上,结合灰色预测理论对加速度进行超前预估,提高了求解过程的实时性。经过仿真分析,验证了该针对多自由度机器人末端加速度的求解及预测方法的合理性,为末端加速度反馈控制提供了支持。 展开更多
关键词 雅可比 关节信息 加速度 数值方法 灰色预测
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A framework of force of information influence and application for C4KISR system
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作者 MAO Shaojie DIAO Lianwang +6 位作者 SUN Yu WANG Heng YI Kan XU Xin MAO Xiaobin ZHANG Kecheng SHENG Long 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期430-443,共14页
The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. It has always been a challenge to quantitatively analyze the function and e... The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. It has always been a challenge to quantitatively analyze the function and effect of information flow through command, control, communications, computer, kill, intelligence,surveillance, reconnaissance (C4KISR) system. In this work, we propose a framework of force of information influence and the methods for calculating the force of information influence between C4KISR nodes of sensing, intelligence processing,decision making and fire attack. Specifically, the basic concept of force of information influence between nodes in C4KISR system is formally proposed and its mathematical definition is provided. Then, based on the information entropy theory, the model of force of information influence between C4KISR system nodes is constructed. Finally, the simulation experiments have been performed under an air defense and attack scenario. The experimental results show that, with the proposed force of information influence framework, we can effectively evaluate the contribution of information circulation through different C4KISR system nodes to the corresponding tasks. Our framework of force of information influence can also serve as an effective tool for the design and dynamic reconfiguration of C4KISR system architecture. 展开更多
关键词 information warfare command control communications computer KILL intelligence surveillance reconnaissance(C4KISR)system information circulation force of information influence information entropy
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深度学习驱动的OFDM索引调制信号检测
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作者 王婵飞 杨婧 +1 位作者 许亚美 何继爱 《计算机科学》 北大核心 2025年第S1期792-797,共6页
在探讨正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统的优化中,一个显著挑战在于其信号检测性能的相对不足。同时,针对基于深度神经网络的索引调制(Deep Neural Network Based Index Modulation,DNN-IM)检测算法... 在探讨正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统的优化中,一个显著挑战在于其信号检测性能的相对不足。同时,针对基于深度神经网络的索引调制(Deep Neural Network Based Index Modulation,DNN-IM)检测算法,普遍存在着误码率及损失值偏高的问题。为了弥补上述难题,文中提出一种基于多层感知机(Multilayer Perceptron,MLP)的索引调制检测算法,即MLP-IM算法。该算法采用融合两个连接层与一个输出层的架构设计,通过挑选的激活函数实现对OFDM索引调制系统中数据比特的精准还原。首先将OFDM索引调制系统的基础理论巧妙应用于数据的预处理阶段,随后利用仿真数据集对MLP神经网络模型进行全面而深入的离线训练,确保模型的稳健性与准确性。在检测阶段,通过MLP-IM检测算法实现了对OFDM索引调制系统的高效检测。仿真结果表明,所提出的MLP-IM算法在误码率控制和损失值两个方面的性能表现与最大似然检测算法相媲美,甚至在某些场景下超越了现有DNN-IM算法的性能,其性能改善幅度在0.2~6 dB的区间内。 展开更多
关键词 正交频分复用(ofDM) 索引调制 信号检测 深度学习 低损失值
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脓毒症肺损伤患者中医证型分布状况与肺损伤相关指标及SOFA、APACHEⅡ评分的相关性分析 被引量:1
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作者 闫云 赵璟 +5 位作者 范风江 包建颖 史晶心 李博 左远航 冯丽霞 《中华中医药学刊》 北大核心 2025年第3期175-178,共4页
目的分析脓毒症肺损伤患者中医证型分布状况与肺损伤相关指标及序贯性器官衰竭评分(sequential organ failure assessment,SOFA)、急性生理和慢性健康状况Ⅱ(Acute Physiology and Chronic Health EvaluationⅡ,APACHEⅡ)评分的相关性... 目的分析脓毒症肺损伤患者中医证型分布状况与肺损伤相关指标及序贯性器官衰竭评分(sequential organ failure assessment,SOFA)、急性生理和慢性健康状况Ⅱ(Acute Physiology and Chronic Health EvaluationⅡ,APACHEⅡ)评分的相关性。方法选取2022年1月—2023年1月医院收治的脓毒症肺损伤患者80例,收集患者的一般资料、肺损伤相关指标[动脉血氧合指数(ratio of partial pressure of O_(2) in arterial blood to fraction of inspired oxygen,PaO_(2)/FiO_(2))、肺泡动脉氧分压差(alveolar-arterial oxygen gradient,P(A-a)O_(2))]及SOFA、APACHEⅡ评分情况,根据中医分型标准对脓毒症肺损伤患者进行分型,比较不同分型的脓毒症肺损伤患者以上各观察指标情况并分析相关性。结果脓毒症肺损伤患者以肺热壅痹证型占比最高、35.00%(28/80),其次为瘀血阻肺型27.50%(22/80),肺塞腑实型23.75%(19/80),水饮郁肺型13.75%(11/80)。不同证型的患者在性别、年龄方面差异均无统计学意义(P>0.05);不同证型的患者肺损伤指标PaO_(2)/FiO_(2)、P(A-a)O_(2)差异均有统计学意义(P<0.05);不同证型的患者SOFA、APACHEⅡ评分差异均有统计学意义(P<0.05)。肺热壅痹、瘀血阻肺、肺塞腑实、水饮郁肺证型与PaO_(2)/FiO_(2)呈显著负相关(P<0.05),与P(A-a)O_(2)、SOFA评分、APACHEⅡ评分呈显著正相关(P<0.05)。结论脓毒症肺损伤患者中医证型主要为肺热壅痹、瘀血阻肺、肺塞腑实、水饮郁肺,与肺损伤相关指标及SOFA、APACHEⅡ评分密切相关,掌握脓毒症肺损伤辨证分型特点并观察患者肺损伤相关指标及SOFA、APACHEⅡ评分变化,对疾病诊治及预后评估具有较高价值。 展开更多
关键词 脓毒症 肺损伤 中医证型 动脉血氧合指数 肺泡动脉氧分压差 序贯性器官衰竭评分 急性生理和慢性健康状况Ⅱ
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Properties of Self-recoverable Mechanoluminescence Phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) and Its Information Encryption Application
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作者 ZHANG Ting WANG Zhijun +3 位作者 WANG Dawei ZHAO Jinxin YANG Zhiping LI Panlai 《发光学报》 EI CAS CSCD 北大核心 2024年第9期1445-1455,共11页
A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)... A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)∶Eu^(3+)can produce red mechanoluminescence,and importantly,it shows good repeatability.The mechanoluminescence of Ca_(5)Ga_(6)O_(14)∶Eu^(3+) results from the piezoelectric field generated inside the material under stress,rather than the charge carriers stored in the traps,which can be confirmed by the multiple cycles of mechanoluminescence tests and heat treatment tests.The mechanoluminescence color can be turned from red to green by co-doping varied concentrations of Tb^(3+),which may be meaningful for encrypted letter writing.The encryption scheme for secure communication was devised by harnessing mechanoluminescence patterns in diverse shapes and ASCII codes,which shows good encryption performance.The results suggest that the mechanoluminescence phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+),Tb^(3+)may be applied to the optical information encryption. 展开更多
关键词 PHOSPHOR MECHANOLUMINESCENCE self-recoverable information encryption
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Review on uncertainty analysis and information fusion diagnosis of aircraft control system
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作者 ZHOU Keyi LU Ningyun +1 位作者 JIANG Bin MENG Xianfeng 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1245-1263,共19页
In the aircraft control system,sensor networks are used to sample the attitude and environmental data.As a result of the external and internal factors(e.g.,environmental and task complexity,inaccurate sensing and comp... In the aircraft control system,sensor networks are used to sample the attitude and environmental data.As a result of the external and internal factors(e.g.,environmental and task complexity,inaccurate sensing and complex structure),the aircraft control system contains several uncertainties,such as imprecision,incompleteness,redundancy and randomness.The information fusion technology is usually used to solve the uncertainty issue,thus improving the sampled data reliability,which can further effectively increase the performance of the fault diagnosis decision-making in the aircraft control system.In this work,we first analyze the uncertainties in the aircraft control system,and also compare different uncertainty quantitative methods.Since the information fusion can eliminate the effects of the uncertainties,it is widely used in the fault diagnosis.Thus,this paper summarizes the recent work in this aera.Furthermore,we analyze the application of information fusion methods in the fault diagnosis of the aircraft control system.Finally,this work identifies existing problems in the use of information fusion for diagnosis and outlines future trends. 展开更多
关键词 aircraft control system sensor networks information fusion fault diagnosis UNCERTAINTY
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Thermal depolymerization of polyethylene terephthalate waste and its use in coal-blending coking
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作者 FANG Shixian SONG Huan +1 位作者 LIU Xiangchun CUI Ping 《燃料化学学报(中英文)》 北大核心 2025年第4期602-612,共11页
This work proposed a strategy to improve the caking index of polyethylene terephthalate(PET)waste,in which low-temperature pyrolysis treatment(LTPT)was used to depolymerize PET waste.The mechanism of G modification wa... This work proposed a strategy to improve the caking index of polyethylene terephthalate(PET)waste,in which low-temperature pyrolysis treatment(LTPT)was used to depolymerize PET waste.The mechanism of G modification was revealed combining thermogravimetric(TG)analysis,Fourier transform infrared spectroscopy,pyrolysis-gas chromatography with mass spectrometric detection,and solid-state 13C nuclear magnetic resonance spectroscopy.Furthermore,crucible coking experiments were also conducted using industrial coal mixture and treated PET with the optimum G(PET300)or raw PET to evaluate the applicability of PET waste in coal-blending coking.According to characterization results of coke reactivity(CR),coke strength after reaction(CSR)indices,TG-related curves,pore volumes,and Raman spectra of the resultant cokes,LTPT could greatly increase the G of PET,and the optimum temperature was 300℃.Specifically,compared with the coke obtained from the blend with PET,the CR of the coke produced from the blend with PET300 decreased by 4.9%,whereas the CSR of the increased by 7.4%,suggesting that LTPT could increase the proportion of PET used for coal-blending coking.The improvement in G is attributed to the changes in C-O/C=O ratio,aliphatic H and aromaticity caused by LTPT. 展开更多
关键词 polyethylene terephthalate PYROLYSIS caking index coking property
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Prediction Method of Polar Navigation Window Period Based on Risk Evaluation
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作者 JIANG Jia−qi SHI Gui−jie WANG De−yu 《船舶力学》 北大核心 2025年第6期986-999,共14页
With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation wind... With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation window period is crucial for navigating in the Arctic route,which is of great significance to the selection of the route and the optimization of navigation.This paper introduces the establishment of a risk index system,determination of risk index weight,establishment of a risk evaluation model,and prediction algorithm for the window period.In addition,data sources of both environmental factors and ship factors are introducted,and their shortcomings are analyzed,followed by introduction of various methods involved in window prediction and analysis of their advantages and disadvantages.The quantitative risk evaluation and window period algorithm can provide a reference for the research of polar navigation window period prediction. 展开更多
关键词 window period risk evaluation polar navigation risk index
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Foam and mildness study of trehalolipid surfactant in rinse off formulations
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作者 Mei Chen Yaoyao Wu +3 位作者 Dandan Xia Xiaowei Chang Guizhen Su Chen Liu 《日用化学工业(中英文)》 北大核心 2025年第9期1153-1162,共10页
The paper investigates the foaming and mildness properties of trehalolipids surfactant in rinse-off formulations,comparing it with the traditional nonionic surfactant alkyl-polyglycolide(APG).Both single surfactant an... The paper investigates the foaming and mildness properties of trehalolipids surfactant in rinse-off formulations,comparing it with the traditional nonionic surfactant alkyl-polyglycolide(APG).Both single surfactant and their surfactant complexes are evaluated.And the results show that trehalolipids have significant advantages in reducing surface tension,improving foam performance,and enhancing mildness.For mildness evaluation,multiple methods are employed in the study,including in vitro cell toxicity,inflammatory markers,colorimetric index of mildness CIM,and in vivo method of human skin patch test.The results show that the addition of trehalolipids increases IC50 and reduces the release of inflammatory markers of the binary surfactant system.However,the incorporation of trehalolipids has some negative effects on the skin’s lipid barrier function.Skin patch test results indicate that the addition of trehalolipids improves the mildness of surfactant system,particularly in sulfate-free system.Overall,trehalolipids,as nonionic surfactants,presents great potential to replace traditional surfactants in rinse off formulations with enhanced mildness and foam performance. 展开更多
关键词 trehalolipids foam MILDNESS colorimetric index of mildness CIM zeta potential skin patch test
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Three-dimensional finite-time optimal cooperative guidance with integrated information fusion observer
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作者 Yiao Zhan Linwei Wang Di Zhou 《Defence Technology(防务技术)》 2025年第4期12-28,共17页
Intercepting high-maneuverability hypersonic targets in near-space environments poses significant challenges due to their extreme speeds and evasive capabilities.To address these challenges,this study presents an inte... Intercepting high-maneuverability hypersonic targets in near-space environments poses significant challenges due to their extreme speeds and evasive capabilities.To address these challenges,this study presents an integrated approach that combines a Three-Dimensional Finite-Time Optimal Cooperative Guidance Law(FTOC)with an Information Fusion Anti-saturation Predefined-time Observer(IFAPO).The proposed FTOC guidance law employs a nonlinear,non-quadratic finite-time optimal control strategy designed for rapid convergence within the limited timeframes of near-space interceptions,avoiding the need for remaining flight time estimation or linear decoupling inherent in traditional methods.To complement the guidance strategy,the IFAPO leverages multi-source information fusion theory and incorporates anti-saturation mechanisms to enhance target maneuver estimation.This method ensures accurate and real-time prediction of target acceleration while maintaining predefined convergence performance,even under complex interception conditions.By integrating the FTOC guidance law and IFAPO,the approach optimizes cooperative missile positioning,improves interception success rates,and minimizes fuel consumption,addressing practical constraints in military applications.Simulation results and comparative analyses confirm the effectiveness of the integrated approach,demonstrating its capability to achieve cooperative interception of highly maneuvering targets with enhanced efficiency and reduced economic costs,aligning with realistic combat scenarios. 展开更多
关键词 Anti-saturation predefined-time observer Nonlinear finite-time optimal control Three-dimensional guidance information fusion
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A review of current studies on the unmanned aerial vehicle-based moving target tracking methods
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作者 Binbin Yan Yuxin Wei +3 位作者 Shuangxi Liu Wei Huang Ruizhe Feng Xiaoqian Chen 《Defence Technology(防务技术)》 2025年第9期201-219,共19页
Unmanned aerial vehicles(UAVs)have become crucial tools in moving target tracking due to their agility and ability to operate in complex,dynamic environments.UAVs must meet several requirements to achieve stable track... Unmanned aerial vehicles(UAVs)have become crucial tools in moving target tracking due to their agility and ability to operate in complex,dynamic environments.UAVs must meet several requirements to achieve stable tracking,including maintaining continuous target visibility amidst occlusions,ensuring flight safety,and achieving smooth trajectory planning.This paper reviews the latest advancements in UAV-based target tracking,highlighting information prediction,tracking strategies,and swarm cooperation.To address challenges including target visibility and occlusion,real-time prediction and tracking in dynamic environments,flight safety and coordination,resource management and energy efficiency,the paper identifies future research directions aimed at improving the performance,reliability,and scalability of UAV tracking system. 展开更多
关键词 Unmanned aerial vehicle(UAV) Tracking methods Moving targets information prediction Tracking strategies Swarm cooperation
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Mechanical response and impact tendency index correction of gangue-coal combined structure
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作者 WEN Zhi-jie XU Chang-long +2 位作者 GONG Feng-qiang ZUO Yu-jun SONG Zhen-qi 《Journal of Central South University》 2025年第6期2288-2306,共19页
To investigate the mechanical response during failure and the impact tendency characteristics of gangue-coal combined structure,uniaxial compression tests were conducted on nine groups of combined structures,each with... To investigate the mechanical response during failure and the impact tendency characteristics of gangue-coal combined structure,uniaxial compression tests were conducted on nine groups of combined structures,each with varying gangue thicknesses and positions.The response patterns of compressive strength,elastic modulus,pre-peak accumulated energy,elastic energy index,and impact energy index were systematically analyzed.Furthermore,a new index for evaluating the impact tendency of gangue-containing coal was proposed,and its effectiveness was verified.The findings are as follows:(1)As the gangue thickness increases,both the compressive strength and the pre-peak energy of the combined structure decrease,whereas the elastic modulus increases accordingly.When the gangue is located in the lower middle position,the combined structure exhibits the lowest compressive strength and elastic modulus but the highest pre peak energy.(2)As the gangue shifts toward the middle position of the combined structure,the failure mode gradually transitions from comple te“crushing”failure to an incomplete“point-type”failure.As gangue thickness further increases,the failure region evolves from overall failure to localized failure,with the degree of failure shifting from complete to incomplete.The K_(crc)value corresponding to“crushing”complete failure is higher and has a stronger impact tendency compared to“point-type”incomplete failure.(3)The proposed comprehensive impact instability evaluation index K_(crc)for the gangue-coal combined structure has shown a significant positive correlation with compressive strength(R_(c))and impact energy index(K_(E)),further verifyi ng its rationality in comprehensively assessing the impact tendency of gangue-containing coal bodies.Applying this index to the evaluation of gangue-containing coal seams provides a more accurate reflection of their impact tendency compared with the residual energy index,which has a wide range of potential applications and practical significance. 展开更多
关键词 gangue-coal combined structure mechanical response peak elastic energy density difference impact tendency comprehensive impact instability index
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The predictive value of NLR and SII in anti⁃MDA5 antibody⁃positive dermatomyositis with rapidly progressive interstitial lung disease
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作者 CAI Qingqing YOU Hanxiao +7 位作者 WANG Lei LÜChengyin SHI Yumeng QIU Yulu WU Lingyun WANG Fang ZHANG Miaojia TAN Wenfeng 《南京医科大学学报(自然科学版)》 北大核心 2025年第2期196-207,共12页
Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(... Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(anti⁃MDA5+)dermatomyositis(DM)develop into the rapidly progressive interstitial lung disease(RPILD).Methods:We retrospectively analyzed the clinical and laboratory data of 124 anti⁃MDA5+DM patients from the First Affiliated Hospital of Nanjing Medical University between March 2019 and September 2023.We identified independent risk factors associated with the development and mortality of RPILD with the Cox regression analysis,and determined the optimal cut⁃off values for predicting adverse outcomes with the receiver operating characteristic(ROC)curve analysis.Results:Among the 124 patients,36 patients(29.03%)developed RPILD,and 39 patients(31.45%)died during the follow⁃up period.The results of multivariate Cox regression analysis showed that the elevated NLR was an independent risk factor for RPILD development,while the elevated SII expression was independently associated with the increased mortality of RPILD.Based on the ROC curve analysis,NLR>6.12 was a predictor for RPILD,and SII>875.79 was associated with increased mortality risk of RPILD.Conclusion:Both NLR and SII are accessible,cost⁃effective,and reliable prognostic indicators for the prognosis of patients with anti⁃MDA5^(+)DM,providing a valuable guidance for clinical management and risk stratification of the disease. 展开更多
关键词 anti⁃melanoma differentiation⁃associated gene 5⁃positive dermatomyositis neutrophil⁃to⁃lymphocyte ratio rapidly pro⁃gressive interstitial lung disease systemic immune⁃inflammation index
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基于CloFormer-Bi-LSTM的液压泵故障诊断方法
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作者 宋宇宁 《现代制造工程》 北大核心 2025年第8期141-150,共10页
针对液压泵故障诊断中信号复杂性高、空间特征信息提取能力不足的问题,提出一种结合CloFormer和Bi-LSTM的故障诊断方法。该方法将Bi-LSTM神经网络嵌入到CloFormer网络,加强模型对故障特征的学习能力,并提高模型对全局长距离信息和局部... 针对液压泵故障诊断中信号复杂性高、空间特征信息提取能力不足的问题,提出一种结合CloFormer和Bi-LSTM的故障诊断方法。该方法将Bi-LSTM神经网络嵌入到CloFormer网络,加强模型对故障特征的学习能力,并提高模型对全局长距离信息和局部时序信息的表征性能。同时,设计一种多层特征信息融合结构,学习和融合多尺度特征,并促进特征信息的流动和传递。最后,将所提方法应用到液压泵故障诊断任务,验证所提方法的有效性。结果表明,所提方法实现了5类液压泵状态的准确诊断,准确率和F_(1)分数分别达到98.74%和98.85%,优于其他5种对比方法。 展开更多
关键词 液压泵 故障诊断 Cloformer 双向长短时记忆网络 全局局部信息
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Effects of Media and Distributed Information on Collaborative Concept-Learning 被引量:1
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作者 傅小兰 《心理与行为研究》 2005年第4期248-255,共8页
The present study explores the effects of media and distributed information on the performance of remotely located pairs of people′s completing a concept-learning task. Sixty pairs performed a concept-learning task u... The present study explores the effects of media and distributed information on the performance of remotely located pairs of people′s completing a concept-learning task. Sixty pairs performed a concept-learning task using either audio-only or audio-plus-video for communication. The distribution of information includes three levels: with totally same information, with partly same information, and with totally different information. The subjects′ primary psychological functions were also considered in this study. The results showed a significant main effect of the amount of information shared by the subjects on the number of the negative instances selected by the subjects, and a significant main effect of media on the time taken by the subjects to complete the task. 展开更多
关键词 学习观 学习心理学 电视传媒 心理应用
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Effect of information delay on string stability of platoon of automated vehicles under typical information frameworks 被引量:12
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作者 肖凌云 高峰 《Journal of Central South University》 SCIE EI CAS 2010年第6期1271-1278,共8页
The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal ve... The effect of the information delay, which was caused by thc naturc of the distance sensors and wireless communication systems, on the string stability of platoon of automated vehicles was studied. The longitudinal vehicle dynamics model was built by taking the information delay into consideration, and three typical information frameworks, i.e., leader-predecessor framework (LPF), multiple-predecessors framework (MPF) and predecessor-successor framework (PSF), were defined and their related spacing error dynamics models in frequency domain were proposed. The string stability of platoon of automated vehicles was analyzed for the LPF, MPF and PSF, respectively. Meanwhile, the related sufficient string stable conditions were also obtained. The results demonstrate that the string stability can be guaranteed tbr the LPF and PSF with considering the information delay, but the ranges of the control gains of the control laws are smaller than those without considering the information delay. For the MPF, the "weak" string stability, which can be guaranteed without considering the information delay, cannot be obtained with considering the information delay. The comparative simulations further demonstrate that the LPF shows better string stability, but the PSF shows better string scalable performance. 展开更多
关键词 string stability information delay information framework automated vehicle intelligent transportation system
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湍流信道下非对称限幅光OFDM自适应索引调制方案 被引量:1
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作者 王惠琴 裴岩浩 +3 位作者 王真 唐崎涵 茹辉 张红彦 《通信学报》 EI CSCD 北大核心 2024年第11期174-183,共10页
针对现有光正交频分复用(OFDM)索引调制技术难以适应信道变化,导致系统传输速率受限的问题,构建了一个以最大化传输速率为目标的阈值优化模型。通过动态地寻找最佳M-QAM调制切换阈值,提出一种光OFDM自适应索引调制方案。在详细介绍信号... 针对现有光正交频分复用(OFDM)索引调制技术难以适应信道变化,导致系统传输速率受限的问题,构建了一个以最大化传输速率为目标的阈值优化模型。通过动态地寻找最佳M-QAM调制切换阈值,提出一种光OFDM自适应索引调制方案。在详细介绍信号的映射原理后,推导出所提方案在不同湍流强度下的最佳阈值和理论误码率。仿真结果表明,与传统光OFDM索引调制方案相比,所提方案在满足目标误码率的前提下,显著提升了系统的传输速率。 展开更多
关键词 索引调制 自适应调制 最佳阈值 传输速率
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