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Redox mechanism of geobattery and related electrical signals using a novel real-time self-potential monitoring experimental platform 被引量:2
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作者 XIE Jing CUI Yi-an +4 位作者 ZHANG Li-juan GUO You-jun CHEN Hang ZHANG Peng-fei LIU Jian-xin 《Journal of Central South University》 CSCD 2024年第11期4155-4173,共19页
Controlled laboratory experiments are proved to be a valuable tool for investigating changes in underground physical properties and the related response of surface geophysical signals.The self-potential(SP)method is w... Controlled laboratory experiments are proved to be a valuable tool for investigating changes in underground physical properties and the related response of surface geophysical signals.The self-potential(SP)method is widely used in mineral resource exploration due to its direct correlation with underground electrochemical gradients.This paper presented the design and construction of an experimental platform based on a multi-channel SP monitoring system.The proposed platform was used to monitor the anodizing corrosion process of different metal blocks from a laboratory perspective,record the real-time SP signal generated by the redox reaction,as well as investigate the geobattery mechanism associated with the natural polarization process of metal mineral resources.The experimental results demonstrate that the constructed SP monitoring platform effectively captures time-series SP signals and provides direct laboratory evidence for the geobattery model.The measured SP data were quantitatively interpreted using the simulated annealing algorithm,and the inversion results closely match the real model.This finding highlights the potential of the SP method as a promising tool for determining the location and spatial distribution of underground polarizers.The study holds reference value for the exploration and exploitation of mineral resources in both terrestrial and marine environments. 展开更多
关键词 SELF-POTENTIAL real-time monitoring laboratory experiment geobattery mechanism quantitative inversion
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Analog-experiment analysis of ash-deposition monitoring model of boiler economizers in power plants
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作者 程伟良 夏国栋 徐寿臣 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第6期680-683,共4页
Ash deposition is a form of particulate fouling, and appears usually in boiler economizers. The ash deposition increases capital expenditure, energy input and maintenance costs. An analog experiment for monitoring ash... Ash deposition is a form of particulate fouling, and appears usually in boiler economizers. The ash deposition increases capital expenditure, energy input and maintenance costs. An analog experiment for monitoring ash deposition was performed from the analogous objective of a 410 t/h boiler economizer to verify the rationality and reliability of the ash-deposition-monitoring model presented in order to increase the security and economy in economizer running. The analog experiment platform is a tube-shell exchanger that conforms well to the conditions of a self-modeling area. The analog flue gas in the shell side is the heated air mixed with ash, and in the tube side the fluid is water heated by the flue gas. The fluid state in the water side and the flue gas side follows the second self-modeling area. A 4-factor-3-level orthogonal table was used to schedule 9 operation conditions of orthogonal experiment, with the 4 factors being heat power, flue gas velocity, ashes grain diameter and adding ashes quantity while the three levels are different values due to different position classes in every factor. The ash deposition thermal resistances is calculated by the model with the measure parameters of temperature and pressure drop. It shows that the values of the ash deposition thermal resistances gradually increase up to a stable state. And the experimental results are reliable by F testing method at α= 0.001. Therefore, the model can be applied in online monitoring of ash deposition in a boiler economizers in power plants and provides scientific decision on ash deposition prediction and sootblowing. 展开更多
关键词 thermal power engineering monitoring model ash deposition orthogonal experiment boiler economizer tube-shell exchanger
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A Study on the Design of Elderly-Following Monitoring Robots Based on AHP
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作者 Xiaorong Wei Jiayu Cao Aihui Yang 《Journal of Electronic Research and Application》 2025年第6期435-442,共8页
This study constructs a design model for elderly-following monitoring robots based on the Analytic Hierarchy Process(AHP),establishing four evaluation dimensions:functional adaptability,interaction usability,environme... This study constructs a design model for elderly-following monitoring robots based on the Analytic Hierarchy Process(AHP),establishing four evaluation dimensions:functional adaptability,interaction usability,environmental adaptability,and safety reliability.Design priorities were determined through expert scoring and weight analysis,followed by practical optimization of structure and interaction.Results indicated that this approach can effectively enhance the scientific rigor of robot design and improve user satisfaction,providing a feasible solution for the design of intelligent elderly-care products. 展开更多
关键词 Analytic hierarchy process Human-robot interaction Industrial design Follow-up monitoring robot User experience
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Screening of TiB2-based ternary composites for X-ray transparent heaters in high-pressure and high-temperature experiments
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作者 Yutian Zhang Guoliang Niu +4 位作者 Pengfei Tan Chuanhui Zhu Huiyang Gou David Walker Man-Rong Li 《Matter and Radiation at Extremes》 2025年第6期122-130,共9页
High-pressure and high-temperature(HPHT)experiments in large-volume presses(LVPs)benefit from reliable,available,and affordable heaters to achieve stable and homogeneous heating and,in some circumstances,X-ray transpa... High-pressure and high-temperature(HPHT)experiments in large-volume presses(LVPs)benefit from reliable,available,and affordable heaters to achieve stable and homogeneous heating and,in some circumstances,X-ray transparency for monitoring of properties of an in situ experiment using X-ray diffraction and contrast imaging techniques.We have developed heaters meeting the above requirements,and we screen the ternary system TiB2–SiC–hexagonal(h)BN(denoted as TSB)to enable manufacture of X-ray transparent heaters for HPHT runs.Heaters fabricated using optimized TSB-631(60%TiB2–30%SiC–10%hBN by weight)have been tested in modified truncated assemblies,showing excellent performance up to 22 GPa and 2395 K in HPHT runs.TSB-631 has good ceramic machinability,outstanding reproducibility,high stability,and negligible temperature gradient for runs at 3–7 GPa with cell assemblies with truncated edge lengths of 8–12 mm.The fabricated heaters not only show excellent performance in HPHT runs,but also demonstrate high X-ray transparency over a wide X-ray wavelength region,indicating potential applications for in situ X-ray diffraction/imaging under HPHT conditions in LVPs and other high-pressure apparatus. 展开更多
关键词 TIB monitoring properties Hexagonal boron nitride X ray transparent heaters large volume presses Ternary composites situ experiment high pressure high temperature experiments
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Study on the spectral response of fiber Bragg grating sensor under non-uniform strain distribution in structural health monitoring 被引量:20
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作者 黄红梅 袁慎芳 《Optoelectronics Letters》 EI 2011年第2期109-112,共4页
Many theoretical studies have been developed to study the spectral response of a fiber Bragg grating (FBG) under non-uniform strain distribution along the length of FBG in recent years. However, almost no experiments ... Many theoretical studies have been developed to study the spectral response of a fiber Bragg grating (FBG) under non-uniform strain distribution along the length of FBG in recent years. However, almost no experiments were designed to obtain the evolution of the spectrum when a FBG is subjected to non-uniform strain. In this paper, the spectral responses of a FBG under non-uniform strain distributions are given and a numerical simulation based on the Runge-Kutta method is introduced to investigate the responses of the FBG under some typical non-uniform transverse strain fields, including both linear strain gradient and quadratic strain field. Experiment is carried out by using loads applied at different locations near the FBG. Good agreements between experimental results and numerical simulations are obtained. 展开更多
关键词 Computer simulation experimentS Fiber Bragg gratings Fiber optic components Fiber optic sensors Numerical methods Runge Kutta methods Structural health monitoring
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Comparison of Using an Electronic System and Conventional Monitoring Method for Monitoring the Quality of Drinking Water and Defects Discovery in Rural Area Water Distribution Network of Abarkouh, Iran 被引量:2
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作者 Reza Ali Fallahzadeh Maryam Gholami +4 位作者 Elham Madreseh Mohammad Taghi Ghaneian Mohamad Hadi Farahzadi Ali Akbar Askarnejad Shahram Sadeghi 《Health》 2015年第1期35-40,共6页
The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventi... The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventional monitoring method (According to ISIR (Institute of Standards and Industrial Research of Iran), 1053 and 4208) and use of electronic system method (Patent in industrial property general office of Iran, 77815). Free chlorine monitoring and pH test done by health workers in the conventional method and the results will be sent to the Health Network monthly. Sampling for microbiological testing is done monthly based on population (According to ISIR, 4208). On the electronic system, the procedure is also done by health workers, but the result will be sent to the receiver device by using a cell phone. According to the chlorine test results if the free chlorine residual reported zero, microbiological sampling was done by a health expert. Finally, the number of chlorine test and microbiological sampling and the results of these experiments collected in the both methods and recorded in SPSS 22 then were analyzed by using chi-square test and Fisher exact test. The result of microbiological experiments shows that the sampling rate decreased 29% in using of electronic system method in comparison to the conventional monitoring method while the number of microbial defect detection increased 19% in drinking water networks monitoring by electronic system. Using of electronic system monitoring can reduce the rate and cost of microbiological sampling and its experiments and increase accuracy of these tests, in this way it will increase the quality and safety of drinking water in distribution network in small and dispersed rural communities. 展开更多
关键词 WATER Distribution Network monitoring MICROBIOLOGICAL experiments WATER Quality RURAL Area
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Semi-implantable device based on multiplexed microfilament electrode cluster for continuous monitoring of physiological ions
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作者 Shuang Huang Shantao Zheng +9 位作者 Mengyi He Chuanjie Yao Xinshuo Huang Zhengjie Liu Qiangqiang Ouyang Jing Liu Feifei Wu Hang Gao Xi Xie Hui-jiuan Chen 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期88-103,共16页
Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in bio... Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in biological subjects.Current semi-implantable devices are mainly based on single-parameter detection.Miniaturized semi-implantable electrodes for multiparameter sensing have more restrictions on the electrode size due to biocompatibility considerations,but reducing the electrode surface area could potentially limit electrode sensitivity.This study developed a semi-implantable device system comprising a multiplexed microfilament electrode cluster(MMEC)and a printed circuit board for real-time monitoring of intra-tissue K^(+),Ca^(2+),and Na^(+)concentrations.The electrode surface area was less important for the potentiometric sensing mechanism,suggesting the feasibility of using a tiny fiber-like electrode for potentiometric sensing.The MMEC device exhibited a broad linear response(K^(+):2–32 mmol/L;Ca^(2+):0.5–4 mmol/L;Na^(+):10–160 mmol/L),high sensitivity(about 20–45 mV/decade),temporal stability(>2weeks),and good selectivity(>80%)for the above ions.In vitro detection and in vivo subcutaneous and brain experiment results showed that the MMEC system exhibits good multi-ion monitoring performance in several complex environments.This work provides a platform for the continuous real-time monitoring of ion fluctuations in different situations and has implications for developing smart sensors to monitor human health. 展开更多
关键词 Multiplexed microfilament electrode cluster Physiological ion sensing Subcutaneous and brain experiment Wearable platform for multi-ion detection Continuous real-time monitoring system
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便携式生态水文实验与监测系统(Eco-monitors)的集成与应用 被引量:2
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作者 宋文龙 杨胜天 +3 位作者 高云飞 王玉娟 董国涛 王志伟 《南水北调与水利科技》 CAS CSCD 北大核心 2012年第5期7-12,共6页
生态水文实验与监测装置的研制对生态水文过程模拟、参数获取与结果验证具有重要意义。在合理创新基础上,构建了便携式生态水文实验与监测系统(Eco-monitors)。Eco-monitors由植被覆盖度动态获取系统(VC-DAS)、便携式光合作用测量系统... 生态水文实验与监测装置的研制对生态水文过程模拟、参数获取与结果验证具有重要意义。在合理创新基础上,构建了便携式生态水文实验与监测系统(Eco-monitors)。Eco-monitors由植被覆盖度动态获取系统(VC-DAS)、便携式光合作用测量系统、便携式人工模拟降雨装置、土壤水运动监测装置及径流/土壤水采样装置等功能模块组成。Eco-monitors及其各功能模块的集成与设计重点突出便携性特点,既包括现有产品如便携式光合作用测量系统、土壤水运动监测装置及径流/土壤水采样装置;也包括自主创新部分如植被覆盖度动态获取系统(VC-DAS)采用摄像头方案代替传统的数码相机,便携式人工模拟降雨装置采用人工压力泵,克服了蓄电池或电力传动装置供电要求高且难以携带的限制。Eco-monitors在多项研究项目中得到了成功应用。 展开更多
关键词 生态水文过程 实验与监测 植被覆盖度 植物生理过程 人工模拟降雨 土壤水
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单相变压器匝间短路故障的漏磁幅值与相位规律分析
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作者 孙毅南 赵维涛 +3 位作者 李雪龙 邵景晖 杨兰均 张正扬 《高电压技术》 北大核心 2026年第1期156-168,共13页
针对变压器现有保护无法及时和准确判别变压器小比例匝间短路故障的不足,分别研究单相变压器正常运行与不同比例的匝间短路故障下变压器漏磁分布规律。该文建立了单相变压器绕组匝间短路计算及仿真模型,搭建了单相变压器匝间短路故障漏... 针对变压器现有保护无法及时和准确判别变压器小比例匝间短路故障的不足,分别研究单相变压器正常运行与不同比例的匝间短路故障下变压器漏磁分布规律。该文建立了单相变压器绕组匝间短路计算及仿真模型,搭建了单相变压器匝间短路故障漏磁测量平台,分析了变压器匝间短路故障前后径向漏磁对称性破坏规律,探究了短路匝匝数与位置对漏磁特征的影响。通过对仿真及实验数据分析可得以下结论:当变压器正常工作时,绕组上下两侧漏磁场方向相反,呈对称分布;当变压器发生匝间短路故障时,漏磁场对称性会被破坏,幅值会随短路匝数的增加而增加,同时漏磁反向点会随短路位置反向移动。最后研究了基于漏磁幅值变化量与漏磁相位反相点位置的变压器匝间短路故障监测方法和漏磁传感器布置方案,可以准确识别0.5%比例变压器匝间短路故障,为变压器匝间短路故障漏磁监测方法提供依据。 展开更多
关键词 变压器 匝间短路故障 漏磁 在线监测 匝间短路实验
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An Integrated Approach to Condition-Based Maintenance Decision-Making of Planetary Gearboxes: Combining Temporal Convolutional Network Auto Encoders with Wiener Process
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作者 Bo Zhu Enzhi Dong +3 位作者 Zhonghua Cheng Xianbiao Zhan Kexin Jiang Rongcai Wang 《Computers, Materials & Continua》 2026年第1期661-686,共26页
With the increasing complexity of industrial automation,planetary gearboxes play a vital role in largescale equipment transmission systems,directly impacting operational efficiency and safety.Traditional maintenance s... With the increasing complexity of industrial automation,planetary gearboxes play a vital role in largescale equipment transmission systems,directly impacting operational efficiency and safety.Traditional maintenance strategies often struggle to accurately predict the degradation process of equipment,leading to excessive maintenance costs or potential failure risks.However,existing prediction methods based on statistical models are difficult to adapt to nonlinear degradation processes.To address these challenges,this study proposes a novel condition-based maintenance framework for planetary gearboxes.A comprehensive full-lifecycle degradation experiment was conducted to collect raw vibration signals,which were then processed using a temporal convolutional network autoencoder with multi-scale perception capability to extract deep temporal degradation features,enabling the collaborative extraction of longperiod meshing frequencies and short-term impact features from the vibration signals.Kernel principal component analysis was employed to fuse and normalize these features,enhancing the characterization of degradation progression.A nonlinear Wiener process was used to model the degradation trajectory,with a threshold decay function introduced to dynamically adjust maintenance strategies,and model parameters optimized through maximum likelihood estimation.Meanwhile,the maintenance strategy was optimized to minimize costs per unit time,determining the optimal maintenance timing and preventive maintenance threshold.The comprehensive indicator of degradation trends extracted by this method reaches 0.756,which is 41.2%higher than that of traditional time-domain features;the dynamic threshold strategy reduces the maintenance cost per unit time to 55.56,which is 8.9%better than that of the static threshold optimization.Experimental results demonstrate significant reductions in maintenance costs while enhancing system reliability and safety.This study realizes the organic integration of deep learning and reliability theory in the maintenance of planetary gearboxes,provides an interpretable solution for the predictive maintenance of complex mechanical systems,and promotes the development of condition-based maintenance strategies for planetary gearboxes. 展开更多
关键词 Temporal convolutional network autoencoder full lifecycle degradation experiment nonlinear Wiener process condition-based maintenance decision-making fault monitoring
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基于STM8的温室环境多参数智能调控系统设计与试验
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作者 王瑞 王耸 +5 位作者 焦锐斌 史慧锋 吴乐天 刘霞 郭申伯 岳秋星 《新疆农机化》 2026年第1期40-44,共5页
针对传统农业温室环境调控依赖人工操作、参数控制精度低、能源消耗大等问题,本文设计了一款基于STM8微控制器的多参数温室环境智能调控系统。该系统采用分段式PID控制算法对通风设备、喷雾装置、补光系统及灌溉设备进行精准调控,并以番... 针对传统农业温室环境调控依赖人工操作、参数控制精度低、能源消耗大等问题,本文设计了一款基于STM8微控制器的多参数温室环境智能调控系统。该系统采用分段式PID控制算法对通风设备、喷雾装置、补光系统及灌溉设备进行精准调控,并以番茄(结果期)为供试对象,通过在乌鲁木齐南山水西沟试验地开展日光温室试验,设置智能调控组(T2)与传统人工调控组(T1)进行对比测试。试验结果表明,相比传统人工调控模式,智能调控组不仅显著提升了环境参数控制稳定性,还节省能耗32.0%,减少人工成本93.3%,番茄株高增长速率提升60.0%,单株结果数增加51.2%,单果重提高10.4%,每亩增收5610元。该系统具备操作简便、稳定性强、成本低等特点,可满足新疆地区不同类型农业温室的智能化调控需求。 展开更多
关键词 STM8 微控制器 温室环境调控 多参数监测 智能控制 试验
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适老化智能家居场景化设计与用户体验提升
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作者 周红丽 刘馨贻 《鞋类工艺与设计》 2026年第1期174-176,共3页
本文基于老年用户身心特点与生活行为,系统梳理适老化智能家居的内涵,提出基于场景化设计的用户体验提升路径。结合智能照明、语音交互、多模态传感和边缘计算技术,构建符合老年人认知习惯与操作能力的五大典型场景设计策略,涵盖早晨唤... 本文基于老年用户身心特点与生活行为,系统梳理适老化智能家居的内涵,提出基于场景化设计的用户体验提升路径。结合智能照明、语音交互、多模态传感和边缘计算技术,构建符合老年人认知习惯与操作能力的五大典型场景设计策略,涵盖早晨唤醒、厨房用餐、卫浴如厕、休闲社交及健康紧急响应。本文构建了多维度用户体验评价框架,强调情感关怀与技术隐形融合,力求破解当前智能家居适老化设计的功能碎片化和体验割裂问题。本文为智能家居产品设计与优化提供了理论支撑和实践指导,推动适老化智能家居服务向更具温度和效率的方向发展。 展开更多
关键词 适老化智能家居 场景化设计 用户体验 多模态交互 健康监测
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考虑泥岩蠕变特性的富水隧洞施工控制研究
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作者 孙星亮 刘博宇 +1 位作者 张岳峰 韩佳伟 《河北工程大学学报(自然科学版)》 2026年第1期45-53,共9页
为探究在围岩蠕变作用下采用不同支护参数和施工方法对隧洞稳定性的影响,以新疆输水隧洞工程为背景,对现场取得的土样开展了三轴蠕变试验,用CVISC模型对试验结果进行泥岩蠕变参数拟合;利用FLAC 3D软件基于实际工况建立数值模型,优化支... 为探究在围岩蠕变作用下采用不同支护参数和施工方法对隧洞稳定性的影响,以新疆输水隧洞工程为背景,对现场取得的土样开展了三轴蠕变试验,用CVISC模型对试验结果进行泥岩蠕变参数拟合;利用FLAC 3D软件基于实际工况建立数值模型,优化支护参数;开展施工控制后的变形监测,验证数值模拟结果的有效性。结果表明:(1)泥岩变形包括施加荷载时产生的瞬时变形和随时间变化的蠕变变形,其中以蠕变变形为主;(2)泥岩蠕变参数拟合度较高,泥岩蠕变特性可通过CVISC模型表征;(3)模拟发现钢拱架布设间距为50 cm,C25混凝土喷层厚度为25 cm,锁脚锚杆打设长度为4.5 m,角度为60°时,能有效减小隧道变形,充分发挥支护结构作用;(4)现场优化施工后的监测数据验证了数值模拟结果的可靠性,证明该施工控制措施下隧洞是稳定的。 展开更多
关键词 软弱泥岩 三轴蠕变试验 蠕变参数识别 支护参数优化 现场监测 时间效应
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Monitoring system experiments on beam loss at SSRF injector 被引量:1
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作者 CAI Jun XIA XiaoBin +4 位作者 XU XunJiang LIU Xin XU JiaQiang WANG GuangHong ZENG Ming 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第S2期279-282,共4页
Experiments on beam loss by using beam loss monitoring (BLM) system were carried out at Shanghai Synchrotron Radiation Facility (SSRF) injector. This system used highly sensitive and current-integrated Si-photodiode d... Experiments on beam loss by using beam loss monitoring (BLM) system were carried out at Shanghai Synchrotron Radiation Facility (SSRF) injector. This system used highly sensitive and current-integrated Si-photodiode detectors and an Ethernet data acquisition (DAQ) system. The experimental results demonstrate that the Si-photodiode detectors are a useful tool that provides dynamic information on beam loss and investigates problems of machine operation. It also shows that the Si-photodiode BLM system is suitable for pulse-radiation of high-energy accelerators. 展开更多
关键词 Si-photodiode beam loss monitoring (BLM) experimentS ETHERNET
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基于无线电被动感知的近月空间航天器天地基监测方案设计
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作者 孙军 陈略 +3 位作者 路伟涛 张雨佳 孔静 韩松涛 《中国图象图形学报》 北大核心 2025年第9期2943-2950,共8页
目的针对地月距离上航天器监测手段地基光学与雷达作用限制,提出一种基于无线电被动感知技术的近月空间航天器天地基联合监测方案,无需主动发射无线电信号,仅利用在轨航天器发送的下行无线电信号实现目标监测。方法首先,介绍了无线电被... 目的针对地月距离上航天器监测手段地基光学与雷达作用限制,提出一种基于无线电被动感知技术的近月空间航天器天地基联合监测方案,无需主动发射无线电信号,仅利用在轨航天器发送的下行无线电信号实现目标监测。方法首先,介绍了无线电被动感知技术的理论方法;然后,设计了一种适用于近月空间航天器的天基、地基与天地基协同监测方案,包括系统架构、工作流程,分析了传感器布局、目标引导、信号接收、TDOA(time difference of arrival)/FDOA(frequency difference of arrival)处理、误差修正、目标定轨与预报等关键技术;最后,通过近月空间在轨航天器无线电被动感知监测实验进行初步验证。结果利用所提方案开展了基于地基测站的近月空间在轨航天器监测实验,有效监测到目标下行信号与多普勒变化运动规律,初步验证了监测方案可行性。结论提出的基于无线电被动感知的近月空间航天器天地基监测方案,可为后续近月空间航天器监测系统设计与实现提供有益的技术参考。 展开更多
关键词 近月空间 航天器 下行信号 无线电被动感知 监测实验
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自然电位法实时监测金属阳极氧化腐蚀实验研究 被引量:2
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作者 谢静 崔益安 黄清华 《地球物理学报》 北大核心 2025年第1期244-259,共16页
金属腐蚀是一种涉及氧化还原反应的自然过程,探测金属腐蚀情况有助于识别金属制品的潜在缺陷或间接圈定地下金属目标体.自然电位法是一种无损物探技术,基于自然电位信号与电化学梯度之间的直接联系,通过定性或定量解释自然电位数据可表... 金属腐蚀是一种涉及氧化还原反应的自然过程,探测金属腐蚀情况有助于识别金属制品的潜在缺陷或间接圈定地下金属目标体.自然电位法是一种无损物探技术,基于自然电位信号与电化学梯度之间的直接联系,通过定性或定量解释自然电位数据可表征金属腐蚀相关特征.本研究基于多通道自然电位观测系统搭建室内沙箱实验平台,通过将铁-铜球体模型放置于自来水中以复现球形金属体的自然极化过程,并实时监测金属阳极氧化腐蚀产生的自然电位信号.实验结果表明自然电位的负、正偶极性分布特征与地电池模型的阴、阳极相对应,揭示了电化学半电池反应理论,并提供了地电池模型的可视化实验室证据.采用贝叶斯框架下的自适应马尔科夫链蒙特卡洛算法开展参数化反演以定量解释实验测量数据,获得了球体模型的几何参数和极化强度,突显出自然电位法在检测金属腐蚀的存在性和严重程度以及确定埋藏金属体的空间分布等应用中极具潜力.本研究为非侵入性探测地下金属管道、未爆弹、岩土工程中的金属结构、陆地金属矿产以及海底热液多金属硫化物矿床等埋藏金属性目标体提供了有价值的见解. 展开更多
关键词 自然电位 金属阳极氧化腐蚀 室内监测实验 参数化反演
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基于原型试验和封装式策略的PCCP断丝信号有效特征挖掘 被引量:2
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作者 杨光 栾博文 +3 位作者 李波 孙锦 朱赵辉 张建伟 《水利学报》 北大核心 2025年第2期170-180,共11页
为提升分布式光纤监测系统对预应力钢筒混凝土管(PCCP)断丝信号的实时探测能力,基于封装式策略构建分析模型,挖掘利于振动模式识别的有效特征参量。应用相位敏感光时域反射(Φ-OTDR)型分布式光纤监测系统采集振动信号,针对时域、频域以... 为提升分布式光纤监测系统对预应力钢筒混凝土管(PCCP)断丝信号的实时探测能力,基于封装式策略构建分析模型,挖掘利于振动模式识别的有效特征参量。应用相位敏感光时域反射(Φ-OTDR)型分布式光纤监测系统采集振动信号,针对时域、频域以及时频域建立原始特征参量集合;引入非线性收敛因子、非线性自适应权值、高斯变异扰动和Tent混沌扰动,对鲸鱼优化算法(WOA)进行改进,在此基础上,借助改进的WOA(IWOA)和层次聚类(HC),提出IWOA-HC有效特征挖掘模型。案例分析结果显示:Fisher、BPSO-HC、WOA-HC和IWOA-HC分别挖掘出61、35、32和27个有效特征参量,利用4组有效特征参量进行振动模式识别,准确率分别为71.11%、86.67%、89.44%和97.22%,IWOA-HC挖掘出的有效特征参量具备最佳的模式识别能力。本研究可为在役PCCP工程的健康诊断及灾害预警提供技术支持。 展开更多
关键词 预应力钢筒混凝土管 断丝实时监测 原型试验 有效特征挖掘 封装式建模
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高温隧道气温变化规律及喷雾降温参数优化研究 被引量:2
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作者 王文 杨继康 +3 位作者 胡吉春 王秀博 张恒 王博 《铁道科学与工程学报》 北大核心 2025年第9期4064-4078,共15页
为优化设计参数,改善施工条件,保障人员安全与工程进度,针对高温隧道施工环境中的降温措施及其效果进行研究。以重庆铁路枢纽东环线金山隧道工程为依托,通过全面收集施工动态信息,系统开展气温监测工作,揭示了高温隧道气温变化的内在规... 为优化设计参数,改善施工条件,保障人员安全与工程进度,针对高温隧道施工环境中的降温措施及其效果进行研究。以重庆铁路枢纽东环线金山隧道工程为依托,通过全面收集施工动态信息,系统开展气温监测工作,揭示了高温隧道气温变化的内在规律。首先,利用温度记录仪对隧道内不同位置的气温进行实时监测,详细分析单循环工序下高地温隧道的气温变化趋势及特性。其次,通过自制模型试验平台,探究不同喷雾流量和喷射角度对高温隧道中不同截面位置温度场分布的影响。研究结果表明:隧道内气温随掌子面距离的增加而逐渐降低,且受爆破作业影响显著。喷雾流量的变化对降温速率具有显著影响,且降温效率在不同区域存在差异。喷头后方区域的降温效率最高,风管出口区域次之,两者之间区域最低。喷雾角度虽不影响隧道各断面的起始降温时刻,但掌子面处的降温速率随喷头角度的增加而增大,其中75°喷雾角度的工况降温效果最为显著。本研究揭示了高温隧道气温变化的复杂性和多样性,通过量化分析不同喷雾流量和角度对降温效果的影响,提出了优化喷雾降温参数的设计方案,为隧道施工降温措施提供了科学依据,为高温隧道施工环境控制提供了实用指导。研究成果对提高隧道施工的安全性、效率和工程质量具有现实意义。 展开更多
关键词 高温隧道 气温监测 喷雾降温 温度场分布 模型试验
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汽轮机叶片监测系统功能可靠性试验研究
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作者 关淳 赵发林 +3 位作者 薛海亮 郭魁俊 马义良 李宇峰 《汽轮机技术》 北大核心 2025年第6期426-430,共5页
对哈尔滨汽轮机厂自主研制的汽轮机叶片监测系统的算法和功能可靠性进行了仿真计算和试验研究,从4个方面进行了可靠性论证:(1)基于有限元仿真计算方法,探究了叶片出现缺口、磕碰等故障后振动特性的变化规律,以证实监测方法的可行性。(2... 对哈尔滨汽轮机厂自主研制的汽轮机叶片监测系统的算法和功能可靠性进行了仿真计算和试验研究,从4个方面进行了可靠性论证:(1)基于有限元仿真计算方法,探究了叶片出现缺口、磕碰等故障后振动特性的变化规律,以证实监测方法的可行性。(2)基于仿真计算的试验叶片,在小型转子试验台上完成了叶片振动监测试验验证,通过叶片频谱识别论证了当前监测系统功能的有效性。(3)基于汽轮机真实长叶片,在大型汽轮机转子试验台上完成了汽轮机长叶片振动监测试验验证,探究了传感器安装、信号调理、数据采集及数据分析等关键技术,为产品工程化提供技术支持。(4)联合示范电厂,完成监测系统现场调试和验证试验,提取出了叶片一阶M0~M4振动的主要成分,与仿真计算结果相对比,证实了当前监测系统工程应用的可靠性。 展开更多
关键词 叶片监测 有限元仿真 试验验证 工程应用
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纤维增强802双马树脂基复合材料成型孔隙演变观测
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作者 陈文龙 吴柯锐 +3 位作者 于雅琳 孙宏杰 周何乐子 周华民 《化工新型材料》 北大核心 2025年第6期192-196,共5页
孔隙是复合材料的主要缺陷之一,成型过程中孔隙演变的研究对低孔隙率成型T800/802双马树脂碳纤维复合材料制件起到积极作用。采用扫描电镜(SEM)表征了未固化预浸料的断面形貌;自主搭建了在线监测平台,原位观测802双马树脂145℃恒温加热... 孔隙是复合材料的主要缺陷之一,成型过程中孔隙演变的研究对低孔隙率成型T800/802双马树脂碳纤维复合材料制件起到积极作用。采用扫描电镜(SEM)表征了未固化预浸料的断面形貌;自主搭建了在线监测平台,原位观测802双马树脂145℃恒温加热过程中不同时刻气泡的形成与生长;设计了层压板成型断点实验,采用金相表征方法统计5个不同时刻点孔隙率。结果表明:成型前预浸料初始孔隙率为7.81%,成型过程中树脂反应生成气体,气体成核形成孔隙并长大,在压力和树脂状态共同作用下,孔隙经历形成-生长-缩小-稳定过程,孔隙率、孔隙数目和尺寸均先增大后减小。 展开更多
关键词 孔隙演变 在线监测 断点实验 孔隙率
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