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一种利用稀疏贝叶斯学习的低复杂度DOA估计算法

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信息工程大学学报 2024年第5期25卷 512-517页

作者：张保华刘广怡梅俸铜沈智翔李鸥信息工程大学河南郑州450001 河南开放大学河南郑州450046

针对有限快拍数下传统利用子空间的多信号分类(MUSIC)算法估计信号波达方向(DOA)性能差,以及采用稀疏贝叶斯学习算法估计信号DOA时复杂度高的问题,提出一种联合利用稀疏贝叶斯学习和消息传递的高精度低复杂度DOA估计算法。该算法首先对... 详细信息

针对有限快拍数下传统利用子空间的多信号分类(MUSIC)算法估计信号波达方向(DOA)性能差,以及采用稀疏贝叶斯学习算法估计信号DOA时复杂度高的问题,提出一种联合利用稀疏贝叶斯学习和消息传递的高精度低复杂度DOA估计算法。该算法首先对信号进行实值化处理,其次把信号因子化为标量,最后使用消息传递策略避开稀疏贝叶斯学习算法每次迭代时的大矩阵求逆,降低计算复杂度。通过仿真对所提出的算法和经典算法进行对比验证,发现该算法在有限快拍数下不仅可以适用稀疏阵列的DOA欠定估计,而且在CPU运算时间方面与空间平滑MUSIC算法相当,且估计精度更高。

关键词：波达方向估计多信号分类稀疏贝叶斯学习消息传递实值化处理

经脑脊液宏基因组二代测序确诊的水痘-带状疱疹病毒脑膜脑炎临床分析

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中国实用神经疾病杂志 2024年第5期27卷 622-626页

作者：贾永林张保华朱丽娟高营礼高成恩开封市中心医院河南开封475000

目的探讨水痘-带状疱疹病毒(VZV)脑膜脑炎患者的诊断方法及脑脊液检查特点。方法回顾性分析开封市中心医院收治的15例应用脑脊液二代测序诊断的VZV脑膜脑炎的临床特点及实验室检查结果并行临床分析。结果 15例VZV脑膜脑炎患者中,11例... 详细信息

目的探讨水痘-带状疱疹病毒(VZV)脑膜脑炎患者的诊断方法及脑脊液检查特点。方法回顾性分析开封市中心医院收治的15例应用脑脊液二代测序诊断的VZV脑膜脑炎的临床特点及实验室检查结果并行临床分析。结果 15例VZV脑膜脑炎患者中,11例表现为头痛,发热7例,合并皮肤带状疱疹8例,面神经麻痹1例,认知功能障碍4例,癫痫发作2例。脑脊液结果:白细胞数轻-中度升高,以淋巴细胞为主,其中6例氯化物降低,5例乳酸增高。结论 VZV脑膜脑炎患者临床上多表现为头痛,合并发热、皮肤带状疱疹者较多。脑脊液宏基因组二代测序是诊断VZV脑膜脑炎的一种新的有效方法。中枢神经系统VZV主要表现为脑膜炎与脑膜脑炎,抗病毒治疗预后良好。

关键词：二代测序水痘-带状疱疹病毒脑膜脑炎脑脊液

Mechanical behaviours of bedded sandstone under hydromechanical coupling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1245-1261页

作者： Junwen zhang Zhixiang Song Lichao zhang Shaokang Wu Shanyong Wang Yang zhang Xukai Dong Jinxin Wang Yanbo Han baohua Kan School of Energy and Mining Engineering China University of Mining and Technology (Beijing)Beijing100083China Jarud Banner Zhahanao'er Coal Industry Co. Ltd.ZhaluteqiInner Mongolia029200China Priority Research Centre for Geotechnical Science & Engineering The University of NewcastleCallaghanNSW 2308Australia

The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal ***,H-M coupling tests of bedded sandstones under identical osmotic pressure and various confining pressures were ***,the evolution curves of stress-strain,permeability and damage,macro-and mesoscopic failure characteristics were ***,the mechanical behaviour was characterized,and finally the failure mechanism was *** results showed that:(1)The failure of the sandstone with the bedding angle of 45°or 60°was the structure-dominant type,while that with the bedding angle of 0°,30°or 90°was the force-dominant type.(2)When the bedding angle was in the range of(0°,30°)or(45°,90°),the confining pressure played a dominant role in influencing the peak ***,withinβ∈(30°,45°),the bedding effect played a dominant role in the peak strength.(3)With the increase in bedding angle,the cohesion increased first,then decreased and finally increased,while the internal friction angle was the opposite.(4)When the bedding angle was 0°or 30°,the“water wedging”effect and the“bedding buckling”effect would lead to the forking or converging shear *** the bedding angle was 45°or 60°,the sliding friction effect would lead to the shear slipping *** the bedding angle was 90°,the combination of the“bedding buckling”effect and shear effect would lead to the mixed tension-shear *** above conclusions obtained are helpful for the prevention of water inrush disasters in water-rich roadways with different dips in coal mines.

关键词： Hydromechanical coupling Bedded sandstones Mechanical behaviour Bedding effect Failure mechanism

MOF‐derived 1D/3D N‐doped porous carbon for spatially confined electrochemical CO2 reduction to adjustable syngas

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Carbon Energy 2024年第8期6卷 1-13页

作者： Wei zhang Hui Li Daming Feng Chenglin Wu Chenghua Sun baohua Jia Xue Liu Tianyi Ma Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials Institute of Clean Energy ChemistryCollege of ChemistryLiaoning UniversityShenyangLiaoningChina School of Science RMIT UniversityMelbourneVictoriaAustralia School of Pharmaceutical and Chemical Engineering Taizhou UniversityTaizhouZhejiangChina Department of Chemistry and Biotechnology Swinburne University of TechnologyHawthornVictoriaAustralia

Electrochemical reduction of CO_(2)to syngas(CO and H_(2))offers an efficient way to mitigate carbon emissions and store intermittent renewable energy in ***,the hierarchical one‐dimensional/three‐dimensional nitrogen‐doped porous carbon(1D/3D NPC)is prepared by carbonizing the composite of Zn‐MOF‐74 crystals in situ grown on a commercial melamine sponge(MS),for electrochemical CO_(2)reduction reaction(CO_(2)RR).The 1D/3D NPC exhibits a high CO/H_(2)ratio(5.06)and CO yield(31 mmol g^(−1)h^(−1))at−0.55 V,which are 13.7 times and 21.4 times those of 1D porous carbon(derived from Zn‐MOF‐74)and N‐doped carbon(carbonized by MS),*** is attributed to the unique spatial environment of 1D/3D NPC,which increases the adsorption capacity of CO_(2)and promotes electron transfer from the 3D N‐doped carbon framework to 1D carbon,improving the reaction kinetics of CO_(2)*** results and charge density difference plots indicate that the active site of CO_(2)RR is the positively charged carbon atom adjacent to graphitic N on 1D carbon and the active site of HER is the pyridinic N on 1D *** presence of pyridinic N and pyrrolic N reduces the number of electron transfer,decreasing the reaction kinetics and the activity of CO_(2)*** CO/H_(2)ratio is related to the distribution of N species and the specific surface area,which are determined by the degree of spatial confinement *** CO/H_(2)ratios can be regulated by adjusting the carbonization temperature to adjust the degree of spatial confinement *** the low cost of feedstock and easy strategy,1D/3D NPC catalysts have great potential for industrial application.

关键词： electrochemical CO_(2)reduction reaction melamine sponge metal‐organic frameworks porous carbon syngas

甜菜夜蛾核型多角体病毒颗粒剂制备及其抗逆性能评价

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世界农药 2024年第4期46卷 58-64页

作者：胡素楠战映妤陈泳汀王淑涵郑桂玲张保华青岛农业大学新农药创制研究所青岛266109

甜菜夜蛾核型多角体病毒(SeNPV)具有专一性和高效性,可以有效控制甜菜夜蛾种群,而且对环境和生态安全。为了提高甜菜夜蛾核型多角体病毒的稳定性,以海藻酸钠为包埋材料,通过优化载体用量和进料速率等条件,采用喷雾法制备了病毒颗粒剂,... 详细信息

甜菜夜蛾核型多角体病毒(SeNPV)具有专一性和高效性,可以有效控制甜菜夜蛾种群,而且对环境和生态安全。为了提高甜菜夜蛾核型多角体病毒的稳定性,以海藻酸钠为包埋材料,通过优化载体用量和进料速率等条件,采用喷雾法制备了病毒颗粒剂,并对其相关性能进行了表征和评价。结果表明:海藻酸钠质量浓度为1%,进料速率为13mL/min时制备的病毒颗粒剂呈不规则形状,颗粒剂产率79.4%,病毒含量1.0×10^(6)PIB/g,D_(50)在130μm左右。经颗粒剂海藻酸钠包埋的甜菜夜蛾核型多角体病毒具有良好的热稳定性和抗紫外性能,同时不会影响其对甜菜夜蛾幼虫的致病力。

关键词：甜菜夜蛾核型多角体病毒颗粒剂制备抗逆性

花生壳生物炭基Bt复合颗粒剂的制备及其性能评价

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现代农药 2024年第3期23卷 51-56页

作者：朱海云朱美琦高明惠王静徐晓庆张保华宁夏工商职业技术学院能源化工学院银川750021 青岛农业大学化学与药学院山东青岛266109 乳山韩威生物科技有限公司山东威海264500

在采用不同热解温度制备生物炭的基础上,筛选出与Bt相容性好的生物炭和颗粒剂助剂,并运用正交试验优化制剂配方和制备工艺。结果表明,热解温度500℃制备的花生壳生物炭(HS-5)与Bt相容性好。优化后的颗粒剂配方(质量分数)为:Bt菌粉22%、... 详细信息

在采用不同热解温度制备生物炭的基础上,筛选出与Bt相容性好的生物炭和颗粒剂助剂,并运用正交试验优化制剂配方和制备工艺。结果表明,热解温度500℃制备的花生壳生物炭(HS-5)与Bt相容性好。优化后的颗粒剂配方(质量分数)为:Bt菌粉22%、生物炭(HS-5)0.5%、润湿剂拉开粉2%、黏结剂硅酸镁铝2%、崩解剂氯化钠2%。最优制粒工艺条件为:筛孔粒径1.0 mm,40℃条件下烘干40 min。所得颗粒剂各项指标符合国家标准。该研究为生物炭与Bt联合应用提供了参考。

关键词：生物炭苏云金杆菌颗粒剂正交试验制备工艺

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Micromorphology of landslide soil Case study on the Jibazi landslide in Yunyang in the Three Gorges Region, China

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Journal of Mountain Science 2006年第2期3卷 147-157页

作者： HE Yurong CUI Peng LIAO Chaolin zhang baohua ZHAO Yu Chengdu Institute of Mountain Hazards and Environment Chinese Academy of Science ＆ Ministry of Water Conservation Chengdu 610064 China

Abstract： Landslide is one of natural catastrophes affecting national economy and people＇s livelihood. There are many reports on the forming mechanism and control of landslide, but the studies on micromorphology of landslide soil are few. There are many potential landslides in the Three Gorges Region in China. In this paper, the micromorphologic features of the Jibazi landslide soil in Yunyang in the Three Gorges Region of the Yangtze River were studied using routine methods, that is, soil micromorphology, X-ray diffraetometer and scanning electron microscope. The main conclusions are as follow：（1） The basic micromorphologic characteristics of the landslide soil are that the fine soil particles are commonly cohesive matrix, finer and lower content of skeleton grains, the microstructures are mainly types of phenocrystal gelatinization, densely chap and fissure structure. As a result, these micromorphologic features affect the discharging of soil water, favor the movement of landslide body and provide an internal basis of materials for the formation of landslide. （2） The concept on the forming material of landslide was proposed, and types of optical beamed clay aggregates, Fe-Mn isolates and glassy material were found in landslide-belt soil, which were remarkably different from the natural soil formation, and had some scientific significance in analyzing the forming mechanism of landslide and distinguishing me landslide-belt soil. （3） Some special micromorphologic and sub-micromorphologic characteristics, such as fingerprint microstructure, clay beamed bedding microstructure, oppressive microstructure, moulage microstructure and extending hole microstncture, could bring useful micromorphologic evidences for the observation and forecasting of landslide. The results mentioned above will bring helpful micromorphologic evidences for distinguishing slide soil, analyzing the formation mechanism of landslide, and monitoring and forecasting the occurrence of landslide.

关键词： Landslide Microstructure forming material of landslide Three Gorges Region China

Accurate Source-Receiver Positioning Method for a High-Resolution Deep-Towed Multichannel Seismic Exploration System

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Journal of Ocean University of China 2024年第2期23卷 415-426页

作者： LI Jing LIU Kai WEI Zhengrong zhang Liancheng LIU Yangting PEI Yanliang LIU Chenguang LIU baohua Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMNRQingdao 266061China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266061China College of Ocean Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou 310018China

The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high vertical and horizontal ***,the quality of deep-towed seismic imaging hinges on accurate source-receiver positioning *** light of existing technical problems,we propose a novel array geometry inversion method tailored for high-resolution deep-towed multichannel seismic exploration *** method is independent of the attitude and depth sensors along a deep-towed seismic streamer,accounting for variations in seawater velocity and seabed slope *** approach decomposes the towed line array into multiline segments and characterizes its geometric shape using the line segment distance and pitch *** optimization parameters for seawater velocity and seabed slope angle,we establish an objective function based on the model,yielding results that align with objective *** the particle swarm optimization algorithm enables synchronous acquisition of optimized inversion results for array geometry and seawater *** validation using theoretical models and practical data verifies that our approach effectively enhances source and receiver positioning inversion *** algorithm exhibits robust stability and reliability,addressing uncertainties in seismic traveltime picking and complex seabed topography conditions.

关键词： high-resolution deep-towed multichannel seismic exploration source-receiver positioning array geometry inversion seawater heterogeneity seabed slope angle

Regulating the inner Helmholtz plane structure at the electrolyte-electrode interface for highly reversible aqueous Zn batteries

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Journal of Energy Chemistry 2024年第8期95卷 57-67,I0002页

作者： Jianghe Liu Sanlue Hu Hexin Guo Guobin zhang Wen Liu Jianwei Zhao Shenhua Song Cuiping Han baohua Li Shenzhen Key Laboratory on Power Battery Safety and Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055GuangdongChina Shenzhen Key Laboratory of Advanced Materials School of Materials Science and EngineeringHarbin Institute of TechnologyShenzhen 518055GuangdongChina Faculty of Materials Science and Energy Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina Shenzhen HUASUAN Technology Co. Ltd.Shenzhen 518055GuangdongChina

The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite *** address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cost,non-toxic maltitol as the electrolyte *** preferential adsorption behavior of maltitol can expel the water from the inner Helmholtz plane,and thus hinder the immediate contact between Zn metal and H_(2)***,strong interaction between maltitol and H_(2)O molecules can restrain the activity of H_(2)***,the"IHP adsorption effect"along with the low LUMO energy level of maltitol-CF_(3)SO_(3)^(-)can promote the in-situ formation of an organic-inorganic complex solid electrolyte interface(SEI)*** a result,the hydrogen/oxygen evolution side reaction,corrosion,and dendrites issues are effectively suppressed,thereby leading to highly reversible and dendrite-free Zn plating/*** Zn‖I_(2)battery with hybrid electrolytes also demonstrates high electrochemical performance and ultralong cycling stability,showing a capacity retention of 75%over 20000 charge-discharge cycles at a large current density of 5 A g^(-1).In addition,the capacity of the device has almost no obvious decay over20000 cycles even at-30℃.This work offers a successful electrolyte regulation strategy via the IHP adsorption effect to design electrolytes for high-performance rechargeable Zn-ion batteries.

关键词： Inner Helmholtz plane Adsorption effect Dendrite suppression SEI layer Zn||I_(2)battery