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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 345-358页

作者： Zan zhou Thomas Man-Hoi Lok Wan-Huan zhou Department of Civil and Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoMacaoChina

Surface wave inversion is a key step in the application of surface waves to soil velocity ***,a common practice for the process of inversion is that the number of soil layers is assumed to be known before using heuristic search algorithms to compute the shear wave velocity profile or the number of soil layers is considered as an optimization ***,an improper selection of the number of layers may lead to an incorrect shear wave velocity *** this study,a deep learning and genetic algorithm hybrid learning procedure is proposed to perform the surface wave inversion without the need to assume the number of soil ***,a deep neural network is adapted to learn from a large number of synthetic dispersion curves for inferring the layer ***,the shear-wave velocity profile is determined by a genetic algorithm with the known layer *** applying this procedure to both simulated and real-world cases,the results indicate that the proposed method is reliable and efficient for surface wave inversion.

关键词： surface wave inversion analysis shear-wave velocity profile deep neural network genetic algorithm

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肠系膜下静脉血栓形成致瘀血性肠病1例

胃肠病学 2019年第7期24卷 447-448页

作者：张寅王军周世亮陈东风陆军军医大学大坪医院消化内科

病例:患者男,64岁。因“腹部反复不适1个月,加重 3 d”于2017年12月3日收治入院。患者于1个月前出现腹部不适,主要表现为阵发性全腹部隐痛,可自行缓解,偶有排便不成形。3 d前饮酒和食用海鲜后,腹痛症状加重,表现为下腹部剧烈绞痛,持续... 详细信息

病例:患者男,64岁。因“腹部反复不适1个月,加重 3 d”于2017年12月3日收治入院。患者于1个月前出现腹部不适,主要表现为阵发性全腹部隐痛,可自行缓解,偶有排便不成形。3 d前饮酒和食用海鲜后,腹痛症状加重,表现为下腹部剧烈绞痛,持续不缓解,伴恶心、呕吐,呕吐物为胃内容物。于我院急诊科就诊,予以解痉、镇痛等治疗后,症状无明显缓解,遂收治入院。体检:体温36.5 ℃,心率 95次/min ,呼吸18次/min,血压117/86 mm Hg(1 mm Hg= 0.133 kPa ),心肺体检无明显异常,腹部平坦,腹软,下腹部压痛,无反跳痛,左下腹稍有肌紧张,似可扪及质硬肠管,移动性浊音阴性,肠鸣音正常。

关键词：肠系膜静脉静脉血栓形成瘀血性肠病诊断治疗

Track-before-detect for bistatic radar based on pseudo-spectrum

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Chinese Journal of Aeronautics 2024年第1期37卷 236-246页

作者： Tao HAN Gongjian zhou School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Marine Environmental Monitoring and Information Processing Ministry of Industry and Information TechnologyHarbin 150001China

Track-Before-Detect(TBD) is an efficient method to detect dim targets for radars. Conventional TBD usually follows an approximate motion model of the target, which may cause an inaccurate integration of the target energy. A TBD technique on basis of pseudo-spectrum in mixed coordinates adopting an accurate motion model for bistatic radar system is developed in this *** predicted position in bistatic polar plane is derived according to a nonlinear function that exactly describes the constant Cartesian velocity motion. Then around the predicted position, a pseudo-spectrum is formulated and its samples are accumulated to the integration frame for energy integration. The evolution of the state and the procedure of accumulation of the target energy are derived elaborately. The superior performance of the proposed method is demonstrated by some simulations.

关键词： Weak target detection Bistatic radar Track-before-detect Pseudo-spectrum Multiframe integration

The prescribed Gauduchon scalar curvature problem in almost Hermitian geometry

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Science China Mathematics 2024年第10期67卷 2357-2372页

作者： Yuxuan Li Wubin zhou Xianchao zhou School of Mathematical Sciences Tongji University Department of Applied Mathematics Zhejiang University of Technology

In this paper, we consider the prescribed Gauduchon scalar curvature problem on almost Hermitian manifolds. By deducing the expression of the Gauduchon scalar curvature under the conformal variation, we reduce the problem to solving a semi-linear partial differential equation with exponential nonlinearity. Using the super-and sub-solutions method, we show that the existence of the solution to this semi-linear equation depends on the sign of a constant associated with the Gauduchon degree. When the sign is negative, we give both necessary and sufficient conditions such that a prescribed function is the Gauduchon scalar curvature of a conformal Hermitian metric. Besides, this paper recovers the Chern-Yamabe problem, the Lichnerowicz-Yamabe problem, and the Bismut-Yamabe problem.

关键词： almost Hermitian manifold Gauduchon connection prescribed scalarcurvature problem

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基于水岩相互作用的岩石力学性能研究

重庆交通大学学报（自然科学版） 2012年第2期31卷 268-273,313页

作者：刘小强周世良尚明芳李怡重庆交通大学河海学院重庆400074

依托云南省富宁港一期工程,现场采集岩石试样,经过不同次数的干湿循环后作常规三轴压缩试验;对实测岩石力学性能参数进行回归分析,得到泥岩及砂岩在水岩相互作用下力学性能的变化规律;基于岩石弹性模量,应用连续介质损伤力学方法对比分... 详细信息

依托云南省富宁港一期工程,现场采集岩石试样,经过不同次数的干湿循环后作常规三轴压缩试验;对实测岩石力学性能参数进行回归分析,得到泥岩及砂岩在水岩相互作用下力学性能的变化规律;基于岩石弹性模量,应用连续介质损伤力学方法对比分析了泥岩及砂岩的损伤劣化特点;应用Hoek-Brown强度准则对岩石力学参数进行转换得到岩体综合强度参数;通过有限单元法得到不同次数的水岩相互作用下架空斜坡码头性能的变化特点。

关键词：水岩相互作用力学性能劣化架空斜坡码头库岸边坡

Effect of CO_(2) Opposing Multiple Jets on Thermoacoustic Instability and NO_(x) Emissions in a Lean-Premixed Model Combustor

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Journal of Thermal Science 2024年第1期33卷 207-221页

作者： zhou Hao HU Liubin Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

This paper experimentally studied the effect of CO_(2) opposing multiple jets on the thermoacoustic instability and NO_(x) emissions in a lean-premixed model *** feasibility was verified from three variables:the CO_(2) jet flow rate,hole numbers,and hole diameters of the *** indicate that the control effect of thermoacoustic instability and NO_x emissions show a reverse trend with the increase of open area ratio on the whole,and the optimal jet flow rate range is 1-4 L/min with CO_(2) opposing multiple *** this flow rate range,the amplitude and frequency of the dynamic pressure and heat release signals CH~* basically decrease as the CO_(2) flow rate increases,which avoids high-frequency and high-amplitude thermoacoustic *** amplitude-damped ratio of dynamic pressure and CH*can reach as high as 98.75% and 93.64% with an optimal open area ratio of 3.72%.NO_(x) emissions also decrease as the jet flow rate increases,and the maximum suppression ratio can reach 68.14%.Besides,the flame shape changes from a steep inverted "V" to a more flat "M",and the flame length will become shorter with CO_(2) opposing multiple *** research achieved the synchronous control of thermoacoustic instability and NO_(x) emissions,which could be a design reference for constructing a safer and cleaner combustor.

关键词： thermoacoustic instability lean-premixed model combustor CO_(2)opposing multiple jets open area ratio NO_(x)emissions

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水位变化对库区某岩质边坡的稳定性影响分析

地下空间与工程学报 2010年第2期6卷 429-435页

作者：左良栋周世良吴飞桥王全重庆交通大学河海学院重庆40007

三峡水库岩质边坡的结构十分复杂、所处的地质环境多样,极易发生失稳破坏。传统的极限平衡理论的分析方法在对岩质边坡的稳定性分析上存在一定的局限性,分析结果存在一定偏差。文章采用有限元强度折减法,分析了库水位变化及岸坡结构面... 详细信息

三峡水库岩质边坡的结构十分复杂、所处的地质环境多样,极易发生失稳破坏。传统的极限平衡理论的分析方法在对岩质边坡的稳定性分析上存在一定的局限性,分析结果存在一定偏差。文章采用有限元强度折减法,分析了库水位变化及岸坡结构面宽度改变与边坡稳定性影响的关系。研究表明,库水位变动速度的增加和结构面宽度的增大都会使得岸坡稳定性降低,两者变化均存在一个临界值,当变化超过这一临界值时,滑动面由浅层向深层发展,安全系数骤降。

关键词：三峡水库岩质边坡稳定性影响因素有限元强度折减

Design of integral sliding mode guidance law based on disturbance observer

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Journal of Systems Engineering and Electronics 2024年第1期35卷 186-194页

作者： zhou Jianping ZHANG Wenjie zhou Hang LI Qiang XIA Qunli School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Informatic Engineering Mianyang Techers’CollegeMianyang 62100China Beijing Institute of Electronic System Engineering Beijing 100854China Beijing Institute of Space Long March Vehicle Beijing 100076China

With the increasing precision of guidance,the impact of autopilot dynamic characteristics and target maneuvering abilities on precision guidance is becoming more and more *** order to reduce or even eliminate the autopilot dynamic operation and the target maneuvering influence,this paper suggests a guidance system model involving a novel integral sliding mode guidance law(ISMGL).The method utilizes the dynamic characteristics and the impact angle,combined with a sliding mode surface scheme that includes the desired line-ofsight angle,line-of-sight angular rate,and second-order differential of the angular *** the same time,the evaluation scenario considere the target maneuvering in the system as the external disturbance,and the non-homogeneous disturbance observer estimate the target maneuvering as a compensation of the guidance *** proposed system’s stability is proven based on the Lyapunov stability *** simulations reveale that ISMGL effectively intercepted large maneuvering targets and present a smaller miss-distance compared with traditional linear sliding mode guidance laws and trajectory shaping guidance ***,ISMGL has a more accurate impact angle and fast convergence speed.

关键词： disturbance observer pilot dynamics integral sliding mode impact angle constraint maneuvering target

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燃煤机组降氮改造与运行优化技术研究

电力安全技术 2020年第5期22卷 45-51页

作者：周世亮何运业天津蓝巢电力检修有限公司天津300380

对不同炉型、不同煤种机组典型超低排放技术路线进行了阐述,并对超低排放标准下脱硝运行优化技术进行了介绍。提高超低排放运行方式下脱硝系统及机组的安全性和经济性,指导燃煤机组科学合理地选择NOx超低排放技术路线。

关键词：燃煤机组超低排放技术路线运行优化

Progresses and Prospects of Asymmetrically Coordinated Single Atom Catalysts for Lithium-Sulfur Batteries

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Energy & Environmental Materials 2024年第4期7卷 48-63页

作者： Rong zhou Shaonan Gu Meng Guo Shuzheng Xu Guowei zhou Key Laboratory of Fine Chemicals in Universities of Shandong Jinan Engineering Laboratory for Multi-scale Functional Materials School of Chemistry and Chemical Engineering Qilu University of Technology(Shandong Academy of Sciences)

Lithium-sulfur batteries (LSBs) are widely regarded as promising next-generation batteries due to their high theoretical specific capacity and low material ***,the practical applications of LSBs are limited by the shuttle effect of lithium polysulfides (LiPSs),electronic insulation of charge and discharge products,and slow LiPSs conversion reaction kinetics.

关键词： asymmetrical coordination conversion catalysis Li-S batteries shuttle effect single atom catalysts