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China Ocean Engineering 2024年第3期38卷 453-466页

作者： zhang guo-xing XIA Xin-lu guo Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

基于多关键点检测加权融合的无人机相对位姿估计算法

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自动化学报 2024年第7期50卷 1402-1416页

作者：葛泉波李凯张兴国南京信息工程大学自动化学院南京210044 江苏大数据分析与智能系统省高校重点实验室南京210044 大气环境与装备技术协同创新中心南京210044 中国飞行试验研究院西安710089

针对无人机降落阶段中无人船受水面波浪影响导致图像产生运动模糊以及获取无人机相对位姿精度低且鲁棒性差的问题,提出一种基于多模型关键点加权融合的6D目标位姿估计算法,以提高位姿估计的精度和鲁棒性.首先,基于无人船陀螺仪得到的运... 详细信息

针对无人机降落阶段中无人船受水面波浪影响导致图像产生运动模糊以及获取无人机相对位姿精度低且鲁棒性差的问题,提出一种基于多模型关键点加权融合的6D目标位姿估计算法,以提高位姿估计的精度和鲁棒性.首先,基于无人船陀螺仪得到的运动信息设计帧间抖动模型,通过还原图像信息达到降低图像噪声的目的;然后,设计一种多模型的级联回归特征提取算法,通过多模型检测舰载视觉系统获取的图像,以增强特征空间的多样性;同时,将检测过程中关键点定位形状增量集作为融合权重对模型进行加权融合,以提高特征空间的鲁棒性;紧接着,利用EPnP(Efficient perspective-n-point)计算关键点相机坐标系坐标,将PnP(Perspective-n-point)问题转化为ICP(Iterative closest point)问题;最终,基于关键点解集的离散度为关键点赋权,使用ICP算法求解位姿以削弱深度信息对位姿的影响.仿真结果表明,该算法能够建立一个精度更高的特征空间,使得位姿解算时特征映射的损失降低,最终提高位姿解算的精度.

关键词：辅助无人机降落舰载视觉系统 6D 位姿估计加权融合关键点检测级联特征提取

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地电阻率观测中信噪比与观测精度

地震地质 2024年第4期46卷 955-971页

作者：张宇王兰炜张世中张兴国胡哲中国地震局地球物理研究所北京100081 中国地震局地震预测研究所北京100036

地电阻率观测方法在地震监测、预测研究中发挥了重要作用。地震监测、预测研究要求测量系统误差小且观测精度高,在测量系统性能指标满足测量最大允许误差的前提下,观测精度就取决于测量过程的信噪比,即观测场地的干扰情况。文中从理论... 详细信息

地电阻率观测方法在地震监测、预测研究中发挥了重要作用。地震监测、预测研究要求测量系统误差小且观测精度高,在测量系统性能指标满足测量最大允许误差的前提下,观测精度就取决于测量过程的信噪比,即观测场地的干扰情况。文中从理论上研究了地电阻率观测中信噪比和观测精度之间的关系,分析了地表和井下不同观测装置条件下信噪比的变化情况。当供电电流不变且主要受到均匀场的干扰影响时,减小极距可有效提高测量的信噪比。当地表装置的测量极距缩小为原来的1/3,或井下装置的测量极距缩小为原来的1/4时,信噪比可提高约20dB。以江宁台不同深度、极距观测结果为例,讨论了江宁台井下装置设计的合理性。文中研究结果可为今后地电阻率观测装置的设计和观测场地的选择提供参考。

关键词：地电阻率信噪比观测精度极距

能源电力系统绿色转型:政策演进逻辑与实践进路

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兰州大学学报（社会科学版） 2024年第3期52卷 96-108页

作者：张国兴冯祎琛聂龑兰州大学管理学院兰州大学经济学院甘肃兰州730000

电力行业是能源消耗和碳排放的重点行业,政策则是推进能源电力行业绿色转型的主要抓手。以政策目标和措施为依据,分析我国能源电力系统节能减排政策的演进规律,揭示其理论逻辑和实践进路。研究结果表明:我国能源电力系统节能减排政策沿... 详细信息

电力行业是能源消耗和碳排放的重点行业,政策则是推进能源电力行业绿色转型的主要抓手。以政策目标和措施为依据,分析我国能源电力系统节能减排政策的演进规律,揭示其理论逻辑和实践进路。研究结果表明:我国能源电力系统节能减排政策沿循“节约能源—环境保护—促进可再生能源发展”的演进脉络,经历“以行政指令为主的探索阶段—以法律法规为主的强化阶段—以行政指令和市场化方式相结合的多元化发展阶段”的演进过程,逐步形成促进节能减污降碳和能源结构优化相协同的循环发展格局。我国能源电力系统转型过程中始终体现以党的意志为意志、以人民为中心、统筹发展和安全的基本特征,节能减排技术创新成效显著。未来,推动能源电力系统绿色安全转型应从培育新质生产力、健全财税金融政策、促进多目标协同增效、增强绿色低碳意识四个方面进行深入的实践探索。

关键词：能源电力系统节能减排政策能源结构转型新质生产力高质量发展

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Flow of Steel in Mold Region During Continuous Casting

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Journal of Iron and Steel Research International 2007年第2期14卷 30-35,41页

作者： zhang xing-guo zhang Wen-xiao JIN Jun-ze J. W. Evans Research Center of Foundry Engineering Dalian University of Technology Dalian 116023 Liaoning China Department of Material Science and Engineering University of California at Berkeley Berkeley CA94720 USA

The particle image velocimetry （PIV） technique was used to study the fluid flow phenomena that occurred during continuous casting, using a water model with dimensions of 1 840mm× 280 mm. Two types of solidified shells, i. e. , the smooth type and the coarse type, were used to characterize the dendrite in order to simulate different liquid-solid interfacial conditions. The influence of the nozzle angle and the immersion depth of nozzle, as well as the casting speed on the flow behavior was investigated quantitatively. The results were as follows：（1） There are two large recirculations above and below the fluid jet in the mold, respectively, under the smooth interface condition. However, in the case of the dendrite solidified shell, it was found that the flow velocity of the fluid decreased and more smaller vortices appeared in the upper region of the mold. （2） The angle and the immersion depth of nozzle are two important factors affecting the flow pattern, and they are also capable of bringing about the change in the flow direction. （3） The higher the casting speed, the higher are the jet stream and the impacting point on the narrow face. However, the high casting speed causes serious fluctuation of the meniscus, and correspondingly leads to various defects.

关键词： particle image velocimetry continuous casting steel fluid flow

Solidification Properties of CaO-SiO_2-TiO_2 Based Mold Fluxes

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Journal of Iron and Steel Research International 2011年第7期18卷 15-19,52页

作者： HE Sheng-ping HUANG Qing-yun zhang guo-xing LU Yong-jian WANG Qian Chongqing Key Laboratory of Metallurgical Engineering College of Materials Science and EngineeringChongqing University Chongqing 400044 China

In continuous casting of peritectic steel grades sensitive to longitudinal cracking, the solidification properties of mold fluxes play an important role in keeping smooth running of continuous casting process and achieving high surface quality of casting strands. To reduce fluorine pollution in molten slag, types of CaO-SiO2-TiO2 （CTS） based mold fluxes were investigated. The solidification and crystallization properties, including viscosity η at 1 573 K, break temperature Tbr, crystallization ratio Rc and solidification mineragraphy were measured, which were compared with those of CaO-SiO2-CaF2 based mold fluxes. The experiments show that there are unstable viscosity-high tem- perature properties and high Tbr in part of CTS slag system, which are bad for lubrication between liquid flux film and strand. And when temperature is below Tbr, the viscosities change slowly during cooling in some part of this slag system, which imply that liquid mold fluxes solidify slowly and it is easy to cause surface longitudinal cracks on strand. Major mineragraphy of the CaO-SiO2-TiO2 based mold fluxes are CaO · TiO2 or CaO · TiO2 and CaO · SiO2 · TiO2. TiN and Ti（C,N） can be formed in mold fluxes bearing high TiO2 during the continuous casting.

关键词： mold flux solidification property peritectic steel mineragraphy

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Y对C611铝合金凝固组织及性能的影响

铸造 2024年第9期73卷 1225-1232页

作者：娄鑫宇孟令刚史淑艳王荫洋亚斌周秉文王军宋运坤张兴国大连理工大学材料科学与工程学院辽宁大连116024 大连理工大学宁波研究院浙江宁波315000 中国兵器科学研究院宁波分院浙江宁波315048

研究了添加Y元素对C611铝合金凝固组织和力学性能的影响。结果表明,随着Y含量的增加,C611合金中的α-Al组织的二次枝晶间距和共晶Si逐渐细化、变质,割裂基体的针状Al_(4)(Fe,Mn)Si_(2)相尺寸逐步减小。当Y含量为0.10%时,Al_(4)(Fe,Mn)Si... 详细信息

研究了添加Y元素对C611铝合金凝固组织和力学性能的影响。结果表明,随着Y含量的增加,C611合金中的α-Al组织的二次枝晶间距和共晶Si逐渐细化、变质,割裂基体的针状Al_(4)(Fe,Mn)Si_(2)相尺寸逐步减小。当Y含量为0.10%时,Al_(4)(Fe,Mn)Si_(2)相的平均长度由48.65μm减小到28.20μm,部分Fe以颗粒状Al_(15)(Fe,Mn)4Si_(2)相形式析出弥散分布在共晶硅当中,对基体起到了一定的强化作用;此时铝合金的抗拉强度和伸长率为166 MPa和6.2%,较未添加Y的基体合金分别提升了7.1%和29.2%。

关键词： C611铝合金稀土元素Y 凝固组织抗拉强度

The dynamics of traveling wavefronts for a model describing host tissue degradation by bacteria

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International Journal of Biomathematics 2024年第3期17卷 265-287页

作者： xing-xing Yang guo-Bao zhang Ge Tian College of Mathematics and Statistics Northwest Normal University Lanzhou Gansu 730070P.R.China

In this paper,we mainly investigate the dynamics of traveling wavefronts for a model describing host tissue degradation by *** first establish the existence of spreading speed,and show that the spreading speed coincides with the minimal wave speed of traveling ***,a lower bound estimate of the spreading speed is ***,we prove that the traveling wavefronts with large speeds are globally exponentially stable,when the initial perturbation around the traveling wavefronts decays exponentially asχ→-∞,but the initial perturbation can be arbitrarily large in other *** adopted methods are the weighted energy and the squeezing technique.

关键词： Host tissue degradation bacterial infection traveling wavefronts minimal wave speed stability

The Evolution of Organic Carbon in Chinese Mollisol Under Different Farming Systems: Validation and Prediction by Using Century Model

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Agricultural Sciences in China 2008年第12期7卷 1490-1496页

作者： GAO Chong-sheng WANG Jian-guo zhang xing-yi SUI Yue-yu Hailun Agro-Ecological Experimental Station Northeast Institute of Geography and Agro-Ecology Chinese Academy of Sciences Harbin150081 P.R.China

Soil organic carbon （SOC） is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processing and assorting concerning data, based on clarifying parameters of Century model need, combined with best use of recorded data of field management, observed data of long-term experiments, climate, soil, and biology, and achieved results from Hailun Agro-Ecological Experimental Station, Chinese Academy of Sciences. The results were showed as follows： Before reclamation, SOC content was around 58.00 g kg^-1, SOC content dropped quickly in early years, and then decreased slowly after reclamation. SOC content was around 34.00 g kg^-1 with a yearly average rate of 8.91‰ decrease before long-term experiments was established. After a long-term experiment, SOC would change under different farming systems. Shift farming system changed as follows： By 20-year model simulation, SOC content decreased from 34.03 to 30.19 g kg^-1, with a yearly average rate of 5.97‰; by 100-year model simulation, SOC content decreased to 24.31 g kg^-1, with a yearly average rate of 3.36‰. Organic farming system changed as follows： By 20-year model simulation, SOC content decreased slowly from 34.03 to 33.39 g kg^-1, with a yearly average rate of 0.95‰, 5‰ less than that of shift farming system; by 100-year model simulation, SOC content decreased to 32.21 g kg^-1, with a yearly average rate of 0.55‰. ＂Petroleum＂ farming system changed as follows： By 20-year model simulation, SOC content decreased from 34.03 to 32.88 g kg^-1, with a yearly average rate of 1.72‰, much more than that of organic farming system; by 100-year model simulation, SOC content decreased to 30.89 g kg^-1, with a yearly average rate of 0.96‰. Combined ＂petroleum＂-organic farming system changed as follows： By 20-year model simulation, SOC content was increased slightly; by 100-year model simulation, SOC content increa

关键词： Century model Chinese mollisol farmland soil organic carbon various farming systems prediction

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电沉积锌用铅基阳极服役后表面结构演变研究

云南冶金 2024年第2期53卷 94-99页

作者：袁绶章林阳董伟陈继园张兴国巢书绪昆明物理研究所云南昆明650217 昆明理工大学材料科学与工程学院云南昆明650093

针对由于析氧反应的过电位对阳极氧化膜的高度依赖性,极大地影响了能耗这一问题,采用扫描电子显微镜(SEM)、能量色散光谱(EDS)、电子探针(EPMA)和X射线衍射(XRD)对Pb基阳极(阳极含量:Pb-0.5%Ag-(0.02~0.03%)Ca-(0.01~0.02%)Sr-(0.01~0.0... 详细信息

针对由于析氧反应的过电位对阳极氧化膜的高度依赖性,极大地影响了能耗这一问题,采用扫描电子显微镜(SEM)、能量色散光谱(EDS)、电子探针(EPMA)和X射线衍射(XRD)对Pb基阳极(阳极含量:Pb-0.5%Ag-(0.02~0.03%)Ca-(0.01~0.02%)Sr-(0.01~0.02%)La)的表面形貌、元素分布和织构进行了表征分析,结果表明:服役后的阳极板表面出现了裂纹和大量空洞。同时还观察了阳极泥的形成可能会导致阳极表面的钝化,影响了其电化学性能。

关键词：电沉积锌铅基阳极服役性能表面结构