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基于机器视觉的导盲杖设计

河南科技 2024年第12期51卷 24-29页

作者：高勇陈凯文张城黄淼重庆移通学院通信与信息工程学院重庆401520

【目的】为了满足视障人士多方面的实际出行需求,设计了一款基于机器视觉的导盲杖。【方法】该系统整体为模块化设计,采用了STM32F407VET6单片机和边缘智能计算K210芯片为核心。其机器视觉功能是利用神经网络和YOLOv2算法训练建立起模型... 详细信息

【目的】为了满足视障人士多方面的实际出行需求,设计了一款基于机器视觉的导盲杖。【方法】该系统整体为模块化设计,采用了STM32F407VET6单片机和边缘智能计算K210芯片为核心。其机器视觉功能是利用神经网络和YOLOv2算法训练建立起模型,并对摄像头拍摄到的实时图像进行检测而实现的。系统自身具备陀螺仪姿态角度测量功能,通过判断系统旋转角度是否达到设定阈值,以此来判断使用者是否有摔倒迹象;系统还具有GPS定位功能,在突发情况下系统会通过串口发送AT指令控制GSM模块向紧急联络人发送位置信息。【结果】该系统各个功能经模拟测试,其机器视觉功能检测的正确率达到99%以上;姿态角度测量误差维持在1°以内;GPS和GSM功能可以定位并发送短信息。【结论】该系统的功能可满足视障人士基本的实际出行需要。此外,图像检测模型的建立,可为今后训练模型以检测更多物体,完善机器视觉功能,应对更多实际出行的情况。

关键词：图像识别卷积神经网络智能导盲杖模块化设计

Comprehensive review of advances in machine-learning-driven optimization and characterization of perovskite materials for photovoltaic devices

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Journal of Energy Chemistry 2025年第2期101卷 298-323页

作者： Bonghyun Jo Wenning chen Hyun Suk Jung School of Advanced Materials Science and Engineering Sungkyunkwan University SKKU Institute of Energy Science and Technology (SIEST) Sungkyunkwan University Department of Future Energy Engineering Sungkyunkwan University

Perovskite solar cells(PSCs) have developed rapidly,positioning them as potential candidates for nextgeneration renewable energy ***,conventional trial-and-error approaches and the vast compositional parameter space continue to pose challenges in the pursuit of exceptional performance and high stability of perovskite-based *** increasing demand for novel materials in optoelectronic devices and establishment of substantial databases has enabled data-driven machinelearning(ML) approaches to swiftly advance in the materials *** review succinctly outlines the fundamental ML procedures,techniques,and recent breakthroughs,particularly in predicting the physical characteristics of perovskite ***,it highlights research endeavors aimed at optimizing and screening materials to enhance the efficiency and stability of ***,this review highlights recent efforts in using characterization data for ML,exploring their correlations with material properties and device performance,which are actively being researched,but they have yet to receive significant ***,we provide future perspectives,such as leveraging Large Language Models(LLMs) and text-mining,to expedite the discovery of novel perovskite materials and expand their utilization across various optoelectronic fields.

关键词： Characterization Data-driven machine learning Perovskite materials Perovskite solar cell

Integration of wearable electronics and heart rate variability for human physical and mental well-being assessment

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Journal of Semiconductors 2025年第1期46卷 58-76页

作者： Feifei Yin Jian chen Haiying Xue Kai Kang Can Lu Xinyi chen Yang Li East China Institute of Photo-Elextro ICs Suzhou 215163China Bengbu Representative Department Bengbu 233000China School of Integrated Circuits Shandong UniversityJinan 250101China

Heart rate variability(HRV)that can reflect the dynamic balance between the sympathetic nervous and parasympathetic nervous of human autonomic nervous system(ANS)has attracted considerable ***,traditional electrocardiogram(ECG)devices for HRV analysis are bulky,and hard wires are needed to attach measuring electrodes to the chest,resulting in the poor wearable experience during the long-term *** with that,wearable electronics enabling continuously cardiac signals monitoring and HRV assessment provide a desirable and promising approach for helping subjects determine sleeping issues,cardiovascular diseases,or other threats to physical and mental *** now,significant progress and advances have been achieved in wearable electronics for HRV monitoring and applications for predicting human physical and mental *** this review,the latest progress in the integration of wearable electronics and HRV analysis as well as practical applications in assessment of human physical and mental health are *** commonly used methods and physiological signals for HRV analysis are briefly ***,we highlighted the research on wearable electronics concerning HRV assessment and diverse applications such as stress estimation,drowsiness detection,***,the current limitations of the integrated wearable HRV system are concluded,and possible solutions in such a research direction are outlined.

关键词： wearable electronics HRV analysis physical and mental well-being machine learning stress detection

Rendering acceleration method based on JND and sample gradient

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Optoelectronics Letters 2025年第3期21卷 177-182页

作者： ZHANG Ripei chen Chunyi School of Computer Science and Technology Qinghai Normal University School of Computer Science and Technology Changchun University of Science and Technology

Currently, the main idea of iterative rendering methods is to allocate a fixed number of samples to pixels that have not been fully rendered by calculating the completion rate. It is obvious that this strategy ignores the changes in pixel values during the previous rendering process, which may result in additional iterative operations.

关键词： Pixels

Soil colloids can significantly enhance spreading of polybromodiphenyl ethers in groundwater by serving as an effective carrier

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Journal of Environmental Sciences 2025年第1期147卷 93-100页

作者： Lin Duan Min Li Jiameng Liu Wei chen College of Environmental Science and Engineering Ministry of Education Key Laboratory of Pollution Processes and Environmental CriteriaTianjin Key Laboratory of Environmental Remediation and Pollution ControlNankai UniversityTianjin 300350China

Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling *** association of PBDEs with soil colloids has been observed,indicating the potential risk to groundwater due to colloid-facilitated ***,the extent to which soil colloidsmay enhance the spreading of PBDEs in groundwater is largely ***,we report the co-transport of decabromodiphenyl ester(BDE-209)and soil colloids in saturated porous *** colloids released froma soil sample collected at an e-waste recycling site in Tianjin,China,contain high concentration of PBDEs,with BDE-209 being the most abundant conger(320±30 mg/kg).The colloids exhibit relatively high mobility in saturated sand columns,under conditions commonly observed in groundwater ***,under all the tested conditions(i.e.,varying flow velocity,pH,ionic species and ionic strength),the mass of eluted BDE-209 correlates linearly with that of eluted soil colloids,even though the mobility of the colloids varies markedly depending on the specific hydrodynamic and solution chemistry conditions ***,the mass of BDE-209 retained in the columns also correlates strongly with themass of retained ***,the PBDEs remain bound to soil colloids during transport in porous *** in this study indicate that soil colloidsmay significantly promote the transport of PBDEs in groundwater by serving as an effective *** might be the reason why the highly insoluble and adsorptive PBDEs are found in groundwater at some PBDE-contaminated sites.

关键词： Polybromodiphenyl ethers Soil colloids E-waste recycling sites Groundwater Facilitated transport

The mechanisms of pH regulation on promoting volatile fatty acids production from kitchen waste

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Journal of Environmental Sciences 2025年第1期147卷 414-423页

作者： Feng Liu Tingting Wang Leiyu Feng Yinguang chen College of Environmental Science and Engineering Tongji UniversityShanghai 200092China TUS-Environmental Science and Technology Development Co. Ltd.Beijing 100084China

The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH *** results showed that pH 8 was considered to be the most suitable condition for acid production,especially for the formation of acetic acid and propionic *** average value of total volatile fatty acid at pH 8 was 8814 mg COD/L,1.5 times of that under blank *** average yield of acetic acid and propionic acid was 3302 mg COD/L and 2891 mg COD/L,*** activities of key functional enzymes such as phosphotransacetylase,acetokinase,oxaloacetate transcarboxylase and succinylcoA transferase were all *** further explore the regulatory mechanisms within the system,the distribution of microorganisms at different levels in the fermentation system was obtained by microbial sequencing,results indicating that the relative abundances of Clostridiales,Bacteroidales,Chloroflexi,Clostridium,Bacteroidetes and Propionibacteriales,which were great contributors for the hydrolysis and acidification,increased rapidly at pH 8 compared with the blank ***,the proportion of genes encoding key enzymes was generally increased,which further verified the mechanism of hydrolytic acidification and acetic acid production of organic matter under pH regulation.

关键词： Kitchen waste Acid fermentation Volatile fatty acids pH regulation Functional genes

Synthesis of ternary geopolymers using prediction for effective solidification of mercury in tailings

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Journal of Environmental Sciences 2025年第1期147卷 392-403页

作者： Xuan Lu Jinfa Guo Fang chen Mengkui Tian School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China

This study used steel slag,fly ash,and metakaolin as raw materials(SFM materials)to create silica-alumina-based geopolymers that can solidify Hg^(2+)when activated with sodiumbased water *** experiments began with a triangular lattice point mixing design experiment,and the results were fitted,analyzed,and *** optimum SFM material mass ratio was found to be 70%steel slag,25%fly ash,and 5%*** optimum modulus of the activator was identified by comparing the unconfined compressive strength and solidifying impact on Hg^(2+)of geosynthetics with different *** SFM geopolymer was then applied in the form of potting to cure the granulated mercury *** inclusion of 50%SFM material generated a geosynthetic that reduced mercury transport to the surface soil by roughly 90%.The mercury concentration of herbaceous plant samples was also reduced by 78%.It indicates that the SFM material can effectively attenuate the migration transformation of ***,characterization methods such as XPS and FTIR were used to investigate the mechanism of Hg^(2+)solidification by geopolymers generated by SFM *** possible solidification mechanisms were proposed as alkaline environment-induced mercury precipitation,chemical bonding s,surface adsorption of Hg^(2+)and its precipitates by the geopolymer,and physical encapsulation.

关键词： Mercury Geopolymer Solidification Tailings

Seismic isolation design and resilience improvement of railway station considering the influence of near-fault pulse-like ground motions

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 257-270页

作者： Pan Yi Song Jiayu chen Qi Liu Yongxin School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Seismic Engineering of Sichuan Province Chengdu 610031China

To improve the resilience of railway stations,a typical station was selected as the research object,and an isolation design was ***-four groups of near-fault pulse-like ground motions were *** seismic resilience of the no-isolation railway stations(NIRS)and the isolation railway stations(IRS)were compared to provide a numerical result of the improvement in *** results show that in the station isolation design,the station's functional requirements and structural characteristics should be considered and the appropriate placement of isolation bearings is under the waiting *** the action of a rare earthquake,the repair cost,repair time,rate of harm and death of the IRS were decreased by 8.04 million,18.30 days,6.93×10^(-3)and 1.21×10^(-3),respectively,when compared to the *** IRS received a seismic resilience grade of three-stars and the NIRS only one-star,indicating that rational isolation design improves the seismic resilience of ***,for the design of stations close to earthquake faults,it is suggested to utilize appropriate isolation techniques to improve their seismic resilience.

关键词： railway station near-fault pulse-like ground motion isolation design seismic resilience resilience improvement

Boron shielding design for neutron and gamma detectors of a pulsed neutron tool

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Nuclear Science and Techniques 2025年第1期36卷 115-126页

作者： Xin-Yang Wang Jun-Yan chen Qiong Zhang University of Electronic Science and Technology of China Chengdu 611731China

Shielding materials are critical for downhole pulsed neutron tool design because they directly influence the accuracy of formation measurements.A well-designed shield configuration ensures that the response of the tool is maximally representative of the formation without being affected by the tool and borehole *** study investigated the effects of boron-containing materials on neutron and gamma detectors based on a newly designed logging-while-drilling tool that is currently undergoing *** the boron content increased,the ability to absorb thermal neutrons increased *** simulation,it was proven that boron carbide(B_(4)C)can be used as an effective boron shielding material for thermal neutrons,and is therefore employed in this *** shield against thermal neutrons migrating from the mud pipes,the optimal shielding thicknesses for the near-and far-neutron detectors were determined to be 5 and 4 *** a porosity of 25 p.u.,near-neutron sensitivity exhibited a 5.6%***,to shield the capture gamma generated by thermal neutrons once they enter the tool from the mud pipe and formation,internal and external shields for the gamma detector were *** results show that the internal shield requires a boron content of 75%,whereas the external shield has a thickness of 14.2 mm thickness and a boron content of 25%to minimize the tool effect.

关键词： Nuclear well logging Pulsed neutron tool Boron shielding