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太行山河北段“23•7”强降雨引发的地质灾害规律研究

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中国地质灾害与防治学报 2024年第2期35卷 55-65页

作者：顾福计钱龙王梦洁沈荣辉李朦王立峰闫国芹河北省地质环境监测院/河北省地质资源环境监测与保护重点实验室河北石家庄050021

强降雨是引发地质灾害的主要因素。中国北方地区目前多侧重短时强降雨引发地质灾害方面的研究,对区域性极端降水条件下地质灾害特征规律方面研究尚存在不足。基于“23•7”强降雨引发的地质灾害样本分析,研究了太行山河北段地质灾害发生... 详细信息

强降雨是引发地质灾害的主要因素。中国北方地区目前多侧重短时强降雨引发地质灾害方面的研究,对区域性极端降水条件下地质灾害特征规律方面研究尚存在不足。基于“23•7”强降雨引发的地质灾害样本分析,研究了太行山河北段地质灾害发生的规律特征。结果表明:(1)地质灾害呈现出多发、群发性态势,发生数量达历史新高,类型以崩塌、滑坡、泥石流为主,激发新的地质灾害明显增多;(2)地质灾害发生时空范围与强降雨区域高度吻合,太行山南段和北段呈现差异性分布;(3)泥石流造成的损失最大,坡面型泥石流明显多发,松散物覆盖型滑坡多发易发。研究结果可为极端降水条件下地质灾害防范提供参考。

关键词：杜苏芮极端降水地质灾害特征规律太行山

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水下SLAM技术：挑战、进展与未来方向

数字海洋与水下攻防 2024年第4期7卷 356-364页

作者：王力锋丛大纲封志文中国船舶及海洋工程设计研究院黑龙江职业学院

水下同步定位与地图构建（SLAM）技术是水下机器人探索未知区域的重要手段，在复杂海洋环境中广泛应用。水下SLAM主要分为3种主流技术：前视声呐SLAM、水下光学SLAM及基于测深信息的SLAM。首先，对这些技术在海底地形测绘和深海资源勘... 详细信息

水下同步定位与地图构建（SLAM）技术是水下机器人探索未知区域的重要手段，在复杂海洋环境中广泛应用。水下SLAM主要分为3种主流技术：前视声呐SLAM、水下光学SLAM及基于测深信息的SLAM。首先，对这些技术在海底地形测绘和深海资源勘探中的应用进行了总结，不同的技术显示出不同的适用性和准确性，其中多波束声呐技术因其高分辨率和大范围覆盖能力，在大规模海底地图构建中展现了优越性。然后，总结了人工智能技术等关键技术在处理复杂海底数据中的应用，例如通过神经网络优化的数据处理提高了地图构建的效率和精度。最后，对未来的SLAM技术进行了展望，未来通过算法优化和硬件发展，进一步提升数据处理速度和降低能耗。

关键词：水下同步定位与地图构建多波束声呐机器人导航传感器融合海底地形测绘

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固定翼无人机飞行参数评估模型与实验

建模与仿真 2024年第3期13卷 3627-3634页

作者：李欣平王立峰李昊晨北方工业大学电气与控制工程学院北京

固定翼无人机飞行过程中,为减小模型参数的不确定性和外界扰动对控制器的影响,本文提出了一种飞行参数估计模型,在STM32上通过编程实现了该模型,通过飞行试验验证了该飞行参数估计模型的可行性。

关键词： STM32 固定翼无人机飞行参数估计模型

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超长钢筋笼分体吊装技术的施工应用研究

中国水能及电气化 2024年第8期 17-23页

作者：戴葱葱王礼峰耿占东北京金河水务建设集团有限公司北京102200

针对超长钢筋笼在吊装施工中可能出现的重心不稳、受施工环境和吊装设备限制等问题,文章以广东省东莞市江库联网原水绕松木山水库段原水管道(主体段)第二标段的地连墙钢筋笼吊装工程为案例,通过分析钢筋笼的制作加固、吊点选择、机械选... 详细信息

针对超长钢筋笼在吊装施工中可能出现的重心不稳、受施工环境和吊装设备限制等问题,文章以广东省东莞市江库联网原水绕松木山水库段原水管道(主体段)第二标段的地连墙钢筋笼吊装工程为案例,通过分析钢筋笼的制作加固、吊点选择、机械选型、分体吊装施工、吊装验算等过程,总结了分体吊装技术在实际应用中存在的挑战、解决方案及关键控制点。研究结果可为超长钢筋笼的吊装施工提供设计经验和工程案例参考,促进施工安全性和效率的提升。

关键词：超长钢筋笼分体吊装双机抬吊吊装验算

Acoustic characteristics of cold-seep methane bubble behavior in the water column and its potential environmental impact

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Acta Oceanologica Sinica 2020年第5期39卷 133-144页

作者： Jiangong Wei Tingting Wu Xiguang Deng Zongze Yu lifeng wang Gas Hydrate Engineering and Technology Center Guangzhou Marine Geological SurveyGuangzhou 510075China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyGuangzhou 510075China

The amount of methane leaked from deep sea cold seeps is enormous and potentially affects the global warming,ocean acidification and global carbon *** is of great significance to study the methane bubble movement and dissolution process in the water column and its output to the *** bubbles produce strong acoustic impedance in water bodies,and bubble strings released from deep sea cold seeps are called"gas flares"which expressed as flame-like strong backscatter in the water *** characterized the morphology and movement of methane bubbles released into the water using multibeam water column data at two cold *** result shows that methane at site I reached 920 m water depth without passing through the top of the gas hydrate stability zone(GHSZ,850 m),while methane bubbles at site II passed through the top of the GHSZ(597 m)and entered the non-GHSZ(above 550 m).By applying two methods on the multibeam data,the bubble rising velocity in the water column at sites I and II were estimated to be 9.6 cm/s and 24 cm/s,*** velocity is positively associated with water depth which is inferred to be resulted from decrease of bubble size during methane ascending in the *** with numerical simulation,we concluded that formation of gas hydrate shells plays an important role in helping methane bubbles entering the upper water bodies,while other factors,including water depth,bubble velocity,initial kinetic energy and bubble size,also influence the bubble residence time in the water and the possibility of methane entering the *** estimate that methane gas flux at these two sites is 0.4×10~6–87.6×10~6 mol/a which is extremely small compared to the total amount of methane in the ocean body,however,methane leakage might exert significant impact on the ocean acidification considering the widespread distributed cold *** addition,although methane entering the atmosphere is not observed,further research is still needed to

关键词： gas bubble methane cold seep Nigerian Continental Margin Greenhouse effect Makran accretion wedge

Efficient Security Multimedia System on Embedded Platform

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China Communications 2010年第4期7卷 120-125页

作者： wang lifeng MENG Qinglei XIAO Chen MA Jian DU Yaogang wang Wendong Beijing Electronic Science and Technology Institute Beijing 100070 China Institute of Network Technology Beijing University of Posts and Telecommunications Beijing 100876 China 706 Institute Second Academy of CASIC Beijing 100854 China School of Computer Science and Technology Bei Hang University Beijing 100083 China

Security video communication is a challenging task,especially for wireless video *** efficient security multimedia system on embedded platform is *** analyzing the hardware architecture and resource,the efficient DSP-based H.264/AVC coding is studied by efficient video coding techniques and system optimizing *** protect the confidentiality and integrity of media information,a novel security mechanism is presented,which includes user identify authentication and a perceptual video encryption algorithm based on exploiting the special feature of entropy coding in *** results show that the proposed hardware framework has high performance and achieves a better balance between security and *** proposed security mechanism can achieve high security and low complexity cost,and has a little effect on the compression ratio and transmission ***’s more,encoding and encryption at the same time,the performance of data process can meet real-time application.

关键词： H.264/AVC Encode Optimizing Encryption Identify Authentication

Vibration coupling effects and machining behavior of ultrasonic vibration plate device for creep-feed grinding of Inconel 718 nickel-based superalloy

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Chinese Journal of Aeronautics 2022年第2期35卷 332-345页

作者： Yang CAO Yejun ZHU Wenfeng DING Yutong QIU lifeng wang Jiuhua XU National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Engineering Nanjing Agricultural UniversityNanjing 210032China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Ultrasonic vibration-assisted grinding(UVAG)is an effective and promising method for machining of hard-to-cut *** article proposed an ultrasonic vibration plate device enabling the longitudinal full-wave and transverse half-wave(L2T1)vibration mode for *** characteristics of two-dimensional coupled vibration in different directions were analyzed on the basis of apparent elastic method and finite element ***,a correction factor was applied to correct the frequency error caused by the apparent elastic ***,the comparative experiments between the conventional creep-feed grinding and UVAG of Inconel 718 nickel-based superalloy were carried *** results indicate that the apparent elastic method with the correction factor is accurate for the design of plate device under the L2T1 vibration *** with the conventional creep-feed grinding,the UVAG causes the reduction of grinding force and the improvement of machined surface quality of Inconel 718 nickel-based ***,under the current experimental conditions,the optimal ultrasonic vibration amplitude is determined as 6μm,with which the minimum surface roughness is achieved.

关键词： Apparent elastic method Machining behavior Ultrasonic vibration-assisted grinding Ultrasonic vibration plate device Vibration coupling effects

Vibration of two-dimensional hexagonal boron nitride

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Theoretical & Applied Mechanics Letters 2018年第6期8卷 408-414,I0005页

作者： Jianpeng Yi lifeng wang Yiqing Zhang State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

The dynamic behavior of two-dimensional nanostructures is important to the future application of nano devices. The vibrational behaviors of single-layered hexagonal boron nitride(h-BN) are studied by molecular dynamics simulation and continuum plate model. The bending stiffness and Poisson’s ratios of h-BN along zigzag direction and armchair direction are calculated. H-BN is softer compared with graphene. The continuum plate model can predict the vibration of h-BN with four edge-clamped boundary conditions well. The electric fields in different directions have obvious influence on the vibration of h-BN. The natural frequency of h-BN changes linearly with the electric field intensity along the polarization direction. The natural frequency of h-BN decreases with the increase of electric field intensity along both positive and negative nonpolarization direction. While the natural frequency of h-BN increases with the increase of electric field intensity along both positive and negative transverse electric field.

关键词： Hexagonal boron nitride Molecular dynamics Natural frequency Electric field

A level set method to reconstruct the discontinuity of the conductivity in EIT

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Science China Mathematics 2009年第1期52卷 29-44页

作者： CHEN WenBin CHENG Jin LIN JunShan wang lifeng School of Mathematical Sciences Fudan UniversityShanghai 200433China Department of Mathematics Michigan State UniversityEast LansingMI 48824USA

In this paper, one level set method is applied to finding the interface of discontinuity of the conductivity in EIT(electrical impedance tomography) problem. By choosing one suitable velocity function, a level set reconstruction algorithm is proposed. The theoretical results for EIT problem and regularization are given. Finally the numerical examples demonstrate that the reconstruction algorithm is efficient and stable.

关键词： EIT reconstruction algorithm level set method 34K29 35J05