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Research on Driver’s Fatigue Detection Based on Information Fusion

Computers, Materials & Continua 2024年第4期79卷 1039-1061页

作者： Meiyan Zhang Boqi Zhao Jipu Li qisong wang Dan Liu Jinwei Sun Jingxiao Liao Harbin Institute of Technology School of Instrument Science and EngineeringHarbin150036China Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong Kong100872China

Driving fatigue is a physiological phenomenon that often occurs during *** the driver enters a fatigued state,the attentionis lax,the response is slow,and the ability todeal with emergencies is significantly reduced,which can easily cause traffic ***,studying driver fatigue detectionmethods is significant in ensuring safe ***,the fatigue state of actual drivers is easily interfered with by the external environment(glasses and light),which leads to many problems,such as weak reliability of fatigue driving ***,fatigue is a slow process,first manifested in physiological signals and then reflected in human face *** improve the accuracy and stability of fatigue detection,this paper proposed a driver fatigue detection method based on image information and physiological information,designed a fatigue driving detection device,built a simulation driving experiment platform,and collected facial as well as physiological information of drivers during ***,the effectiveness of the fatigue detection method was *** movement feature parameters and physiological signal features of drivers’fatigue levels were *** driver fatigue detection model was trained to classify fatigue and non-fatigue states based on the extracted *** rates of the image,electroencephalogram(EEG),and blood oxygen signals were 86%,82%,and 71%,*** fusion theory was presented to facilitate the fatigue detection effect;the fatigue features were fused using multiple kernel learning and typical correlation analysis methods to increase the detection accuracy to 94%.It can be seen that the fatigue driving detectionmethod based onmulti-source feature fusion effectively detected driver fatigue state,and the accuracy rate was higher than that of a single information *** summary,fatigue drivingmonitoring has broad development prospects and can be used in traffic accident prevention and wearable dr

关键词： Driving fatigue information fusion EEG blood oxygen

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Experimental study on flocculation and sedimentation characteristics of cohesive fine sediment measured using ultrasound in the Pearl River Estuary

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International Journal of Sediment Research 2023年第6期38卷 880-890页

作者： Qinqin Liu Xiaojian Liu Jian Chen Peng Hou Yong He qisong wang Xiaowei Zhu Qiang wang Huan Gao Pearl River Hydraulic Research Institute Pearl River Water Resources Commission of the Ministry of Water Resources Key Laboratory of the Pearl River Estuary Regulation and Protection of the Ministry of Water Resources School of Water Conservancy North China University of Water Resources and Electric Power Department of the College of Water Conservancy and Hydropower Engineering Hohai University

Flocculation-settling of cohesive fine sediment is the main cause of sediment deposition and changes in topography and geomorphology in ***,studies on estuary morphology have often focused on a single influencing factor,and sediment deposition characteristics under disturbances in sediment concentration,moisture content,and external forces have rarely been considered *** authors propose an ultrasound-assisted flocculation-settling method to analyze the various factor affecting cohesive *** current study examined the sedimentation patterns of cohesive sediment with a sediment content concentration of 30%-80% through ultrasound *** results show that when the sediment concentration is 40%-50%,the best effect on flocculation and sedimentation is induced by ultrasound *** corresponding settling height at the clear-muddy water interface is 3.05-3.45 cm,and the settling rate is 0.161-0.173 cm/***,using ultrasound waves,a moisture content of the sediment concentration of 30%-80% was analyzed based on wet and dry *** a sediment concentration of 50% as an example,the maximum values of the variation in the water contents of the upper,middle,and lower layers of the wet basis were 0.82%,0.51%,and0.37%,respectively,whereas those of the upper,middle,and lower layers of the dry basis were 4.77%,1.07%,and 0.60%,***,the moisture content of dry and wet sediment varied as follows:Wupper> Wmiddle> *** current research results can provide a theoretical basis and technical reference for siltation in channels,harbors,and reservoirs;the evolution of submarine deltas and coastal beaches;transportation of fluid mud;and the treatment of hyper-concentrated sediment flows.

关键词： Cohesive sediment Flocculation-settling Moisture content Ultrasound experiments

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连续法制备短切石英纤维/酚醛树脂预混料的固化反应动力学及其模压制品性能

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北京化工大学学报（自然科学版） 2024年第1期51卷 49-58页

作者：王齐崧宋金梅杨帆张薇张翠妙北京玻钢院复合材料有限公司北京102101

采用连续浸胶法,使用自制的压辊式浸胶槽制备了短切石英纤维/酚醛树脂预混料,通过红外光谱法(FT-IR)、热重分析法(TG)和差示扫描量热法(DSC)对预混料进行了表征,并研究了其固化反应动力学。结果表明,溶剂乙醇影响石英纤维的浸胶过程,连... 详细信息

采用连续浸胶法,使用自制的压辊式浸胶槽制备了短切石英纤维/酚醛树脂预混料,通过红外光谱法(FT-IR)、热重分析法(TG)和差示扫描量热法(DSC)对预混料进行了表征,并研究了其固化反应动力学。结果表明,溶剂乙醇影响石英纤维的浸胶过程,连续法制备的石英纤维/酚醛树脂预混料能够降低乙醇的影响;预混料的固化工艺参数为:凝胶温度108.40℃,固化温度183.04℃,后处理温度264.47℃;固化反应级数为0.95,固化反应动力学模型为:dα/dt=Aexp(-ΔE/RT)(1-α)n=4.3×10^(12)exp(-140.74/RT)(1-α)0.95。使用模压法对所制备的预混料进行压制,得到石英纤维/酚醛树脂复合材料的模压制品,该模压制品在800℃下的质量残留率为82.3%,拉伸强度为58 MPa,断裂伸长率为0.353%,剪切强度为105 MPa,线烧蚀率为0.088 mm/s,烧蚀表面形貌未见异常,结果表明采用连续法制备的石英纤维/酚醛树脂预混料的模压制品具有较好的耐热性、烧蚀性和力学性能。

关键词：连续法石英纤维酚醛树脂预混料固化反应动力学性能

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General Optimal Trajectory Planning:Enabling Autonomous Vehicles with the Principle of Least Action

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Engineering 2024年第2期33卷 63-76页

作者： Heye Huang Yicong Liu Jinxin Liu qisong Yang Jianqiang wang David Abbink Arkady Zgonnikov School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China Department of Cognitive Robotics Faculty of MechanicalMaritime and Materials Engineering(3mE)Delft University of TechnologyDelft 2628Netherlands Department of Software Technology Faculty of Electrical EngineeringMathematics and Computer ScienceDelft University of TechnologyDelft 2628Netherlands Xi’an Institute of High-Technology Xi’an 710051China

This study presents a general optimal trajectory planning(GOTP)framework for autonomous vehicles(AVs)that can effectively avoid obstacles and guide AVs to complete driving tasks safely and ***,we employ the fifth-order Bezier curve to generate and smooth the reference path along the road *** coordinates are then transformed to achieve the curvature continuity of the generated *** the road constraints and vehicle dynamics,limited polynomial candidate trajectories are generated and smoothed in a curvilinear coordinate ***,in selecting the optimal trajectory,we develop a unified and auto-tune objective function based on the principle of least action by employing AVs to simulate drivers’behavior and summarizing their manipulation characteristics of“seeking benefits and avoiding losses.”Finally,by integrating the idea of receding-horizon optimization,the proposed framework is achieved by considering dynamic multi-performance objectives and selecting trajectories that satisfy feasibility,optimality,and *** simulations and experiments are performed,and the results demonstrate the framework’s feasibility and effectiveness,which avoids both dynamic and static obstacles and applies to various scenarios with multi-source interactive traffic ***,we prove that the proposed method can guarantee real-time planning and safety requirements compared to drivers’manipulation.

关键词： Autonomous vehicle Trajectory planning Multi-performance objectives Principle of least action

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EEMD and bidimensional RLS to suppress physiological interference for heterogeneous distribution in fNIRS study

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Journal of Innovative Optical Health Sciences 2018年第6期11卷 97-108页

作者： Yan Zhang Dan Liu qisong wang Xin Liu Chunling Yang Jinwei Sun Jingyang Lu Peter Rolfe School of Electrical Engineering and Automaton Harbin Institute of Technology HarbinP.R.China School of Transportation Science and Engineering Harbin Institute of Technology HarbinP.R.China Intelligent Fusion Technology Inc.GermantownMDUSA

Near-infrared spectroscopy(NIRS)can provide the hemodynamics information based on the hemoglobin concentration representing the blood oxygen metabolism of the cerebral cortical,which can be deployed for the cerebral function ***,NIRS-based cerebral function detection accuracy can be signi¯cantly in°uenced by the physiological activities such as cardic cycle,respiration,spontaneous low-frequency oscillation and ultra-low frequency *** distribution difference of the capillary,artery and vein leads to the heterogeneity feature of the cerebral *** the case that the heterogeneity is not serious,good detection accuracy and stable performance can be achieved through the regression analysis as the reference signal can well represent the interference in the measurement signal when conducting the multi-distance measurement *** direct use of the reference signal to estimate the interference is not able to achieve good performance in the case that the heterogeneity is *** this study,the cerebral function activity signal is extracted using recursive least square(RLS)method based on the multi-distance measurement method in which the reference signal is processed by ensemble empirical mode decomposition(EEMD)*** temporal and dimensional correlation of the neighboring sampling values are applied to estimate the interference in the measurement *** Carlo simulation based on a heterogeneous model is adopted here to investigate the effectiveness of this *** results show that this methodology can effectively suppress the physiological interference and improve the detection accuracy of cerebral activity signal.

关键词： Ensemble empirical mode decomposition recursive least square methods physiological interference heterogeneous distribution

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江南造山带西南段宰便辉绿岩年代学、地球化学及其构造意义

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岩石学报 2022年第4期38卷 1202-1218页

作者：王琦崧王林均孙思辰周家喜钟昌悦贵州民族大学建筑工程学院贵阳550025 福建省地质矿产勘查开发局福州350001 云南大学地球科学学院云南省高校关键矿产成矿学重点实验室昆明650500

宰便地区位于江南造山带西南段,发育有一系列新元古代镁铁质-超镁铁质火成岩。然而,其成因与构造背景仍存在广泛争议。因此,本文选择江南造山带西南段宰便辉绿岩为研究对象,系统开展岩石学、地球化学、Nd-Hf同位素和锆石U-Pb年代学研究... 详细信息

宰便地区位于江南造山带西南段,发育有一系列新元古代镁铁质-超镁铁质火成岩。然而,其成因与构造背景仍存在广泛争议。因此,本文选择江南造山带西南段宰便辉绿岩为研究对象,系统开展岩石学、地球化学、Nd-Hf同位素和锆石U-Pb年代学研究。研究结果表明,辉绿岩具有高Mg^(#)(50~69)、高Al_(2)O_(3)(13.94%~18.63%)、低钾(0.03%~0.33%)、低磷(0.04%~0.28%)特征,显示为低钾拉斑系列岩石特点。同时,岩石整体相对富集Th、U等大离子亲石元素,亏损Nb和Y等高场强元素,Eu具有微弱负异常特征。辉绿岩的Nb/Ta、Zr/Nb比值揭示了母岩浆在岩浆侵位过程中未发生地壳混染。3件样品的锆石U-Pb年龄分别为820.7±3.0Ma、821.1±9.2Ma和823.1±9.5Ma,表明岩浆侵位时代为新元古代早期。锆石ε_(Hf)(t)值介于-13.6~7.7之间,Hf的t_(DM2)值介于1214~2547Ma之间,结合全岩地球化学特征,揭示其原始岩浆可能源于富集地幔,并伴有一定的亏损地幔参与。综合前人和本次研究的地质、地球化学和年代学数据,本文认为江南造山带西南段宰便地区在新元古代早期处于板内构造环境。

关键词：锆石U-Pb年龄岩石地球化学 Lu-Hf同位素江南造山带宰便地区华南

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Walking Rehabilitation Evaluation Based on Gait Analysis

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Journal of Biosciences and Medicines 2020年第6期8卷 215-223页

作者： Meiyan Zhang Jinwei Sun qisong wang Dan Liu School of Instrumentation science and engineering Harbin Institute of Technology Harbin China

With the development of medicine and the improvement of people’s living standards, the issue of rehabilitation is getting more and more attention. Gait rehabilitation provides a brand-new treatment method for patients with walking disfunction. It is currently recognized as an advanced rehabilitation medical method in the world. In recent years, the number of patients suffering from dyskinesias in the lower limbs in China has been increasing, and the society's demand for walking rehabilitation treatment is also increasing. The emergence of gait rehabilitation solves the problem of fewer therapists and more patients, reduces the intensity of the therapist’s work, and has the incomparable advantage that traditional rehabilitation methods lack. However, because there are no mature related products in China at present, and the prices of foreign products are very expensive, domestic medical institutions have not yet put them into practice. Accelerating the development of gait re-habilitation equipment is of great significance for improving China’s medical level, improving the quality of life of patients, and reducing social burden. Usually, high-precision optical sensors are installed on human limbs or using high-speed cameras to capture motion. However, due to the high cost of the equipment, the relative high price of image processing software when processing the collected motion data. In this paper, the acceleration sensors are installed on the human body and the data in a gait cycle can be obtained. After smoothing, using it as the input signal for gait feature extraction and classification. In order to classify normal gait and abnormal gait for evaluation and better walking rehabilitation.

关键词： Rehabilitation Gait Accelerator Sensor SVM

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东天山马庄山金矿区赋矿石英斑岩的岩石成因和构造背景:元素地球化学、U-Pb年代学和Sr-Nd-Hf同位素约束

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岩石学报 2019年第5期35卷 1503-1518页

作者：王琦崧张静王肃于立栋肖兵中国地质大学地质过程与矿产资源国家重点实验室北京100083 中国科学院广州地球化学研究所中国科学院矿物学与成矿学重点实验室广州510640

马庄山金矿位于东天山东段,矿区出露有大量的石英斑岩,总体上呈北东走向,沿矿区中部断裂侵入。石英斑岩呈灰白色,具斑状结构,斑晶主要为石英,少量正长石和斜长石,基质为长英质和少量暗色矿物。石英斑岩的Na_2O+K_2O含量为3. 55%～9. 67%... 详细信息

马庄山金矿位于东天山东段,矿区出露有大量的石英斑岩,总体上呈北东走向,沿矿区中部断裂侵入。石英斑岩呈灰白色,具斑状结构,斑晶主要为石英,少量正长石和斜长石,基质为长英质和少量暗色矿物。石英斑岩的Na_2O+K_2O含量为3. 55%～9. 67%,Al_2O_3含量(10. 37%～14. 28%),K_2O/Na_2O比值为2. 57～66. 5,显示富碱高钾、过铝质特征;稀土含量中等(65×10^(-6)～161×10^(-6)),轻重稀土分异中等([La/Yb]N=6. 15～12. 5),相对富集轻稀土元素、具弱的负Eu异常。微量元素总体富集Rb、K、Th、U和Pb,亏损Sr、Ba、P、Nb和Ti等元素,与活动大陆边缘弧火成岩的微量元素特征一致。马庄山石英斑岩的SiO_2与P_2O_5呈现负相关关系,Y、Th与Rb均呈现正相关的关系,说明研究区的次火山岩属于I型花岗岩类。对马庄山石英斑岩内岩浆锆石进行LA-ICP-MS U-Pb定年,获得一致曲线年龄为315. 4±0. 6Ma(MSWD=0. 67),加权平均年龄为316. 0±2. 0Ma(MSWD=0. 23),将矿区内以石英斑岩为主的次火山岩侵位时间限定在314～318Ma。石英斑岩具有较高的(87Sr/86Sr)i值(0. 7077～0. 7102),较低的εNd(t)值(-1. 62～1. 82),Nd的二阶段模式年龄(tDM2)为0. 9～1. 2Ga,εHf(t)值为-3. 2～0. 4,tDM2在1. 28～1. 51Ga之间,暗示岩石来自于下地壳物质重熔,可能有部分地幔物质加入。综合石英斑岩的地质、地球化学和年代学特征,认为东天山东段,在晚石炭世,马庄山地区处于与俯冲相关的活动陆缘弧环境。

关键词：东天山石英斑岩锆石U-Pb年龄岩石地球化学 Sr-Nd-Hf同位素

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Walking Rehabilitation Evaluation Based on Gait Analysis

Walking Rehabilitation Evaluation Based on Gait Analysis

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作者： Meiyan Zhang Jinwei Sun qisong wang Dan Liu School of Instrumentation science and engineering Harbin Institute of Technology

With the development of medicine and the improvement of people’s living standards, the issue of rehabilitation is getting more and more attention. Gait rehabilitation provides a brand-new treatment method for patients with walking disfunction. It is currently recognized as an advanced rehabilitation medical method in the world. In recent years, the number of patients suffering from dyskinesias in the lower limbs in China has been increasing, and the society’s demand for walking rehabilitation treatment is also increasing. The emergence of gait rehabilitation solves the problem of fewer therapists and more patients, reduces the intensity of the therapist’s work, and has the incomparable advantage that traditional rehabilitation methods lack. However, because there are no mature related products in China at present, and the prices of foreign products are very expensive, domestic medical institutions have not yet put them into practice. Accelerating the development of gait rehabilitation equipment is of great significance for improving China’s medical level, improving the quality of life of patients, and reducing social burden. Usually, high-precision optical sensors are installed on human limbs or using high-speed cameras to capture motion. However, due to the high cost of the equipment, the relative high price of image processing software when processing the collected motion data. In this paper, the acceleration sensors are installed on the human body and the data in a gait cycle can be obtained. After smoothing, using it as the input signal for gait feature extraction and classification. In order to classify normal gait and abnormal gait for evaluation and better walking rehabilitation.

关键词： Rehabilitation Gait Accelerator Sensor SVM

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吉林东部天然次生林下光强衰减的空间分布特征

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南京林业大学学报（自然科学版） 2023年第1期47卷 101-108页

作者：王麒淞国庆喜东北林业大学生态研究中心森林生态系统可持续经营教育部重点实验室黑龙江哈尔滨150040

【目的】探究长白山北坡不同林型天然次生林下空间尺度及方位间的光强衰减特征。【方法】以吉林东部长白山北坡天然次生林5块0.6 hm^(2)样地为研究对象,调查了样地内乔木生长及光强衰减状况,对林型、空间尺度及方位进行划分,采用移动窗... 详细信息

【目的】探究长白山北坡不同林型天然次生林下空间尺度及方位间的光强衰减特征。【方法】以吉林东部长白山北坡天然次生林5块0.6 hm^(2)样地为研究对象,调查了样地内乔木生长及光强衰减状况,对林型、空间尺度及方位进行划分,采用移动窗口法分析不同空间尺度下森林群落结构对林下光强衰减的影响。【结果】吉林东部天然次生林乔木胸高断面积与林下光强衰减率相关性显著(P<0.01)。随着空间尺度增大,乔木胸高断面积与光强衰减率的相关系数逐渐增大,大部分林型在内侧窗口达到10 m×10 m时,光强衰减率与乔木胸高断面积显著正相关(P<0.01),在25 m×25 m尺度时相关系数最大,内侧窗口周围10 m内的乔木也与内侧窗口下的光强衰减率显著正相关(P<0.01)。东侧、南侧的树木对于内侧窗口下的光强衰减率影响比西侧、北侧影响更大。【结论】通过移动窗口法可以分析不同林型乔木对于林下光强衰减的影响范围,与耐阴树种相比,喜光树种乔木胸高断面积与光强衰减率在更多尺度下显著相关;在(10 m×10 m)~(40 m×40 m)的尺度范围内,多数林型乔木胸高断面积与光强衰减率显著正相关(P<0.01)。不同方位的乔木对于光强衰减的影响也存在差异。

关键词：天然次生林光环境光强衰减空间异质性移动窗口法长白山北坡

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