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Engineering Cognition of State Transition Matrix and the Unique Discrimination Method

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Wuhan University Journal of Natural Sciences 2020年第1期25卷 65-70页

作者： zhang yuye College of Physics and Electronics Engineering Xianyang Normal CollegeXianyang 712000ShaanxiChina

State transition matrix is an important concept in modern control system. It studies the motion law of linear control system from initial state to any state at time t. In this paper, joining an engineering example, an approach to determine zero-input responses is developed, and the design of simulation experiments with the aid of Matlab is used to illustrate the physical meaning of it. Furthermore, during the engineering application, for the discrimination of state transition matrix, a discrimination method of state transition matrix is proposed based on related theorems and an effective method is derived by calculating characteristics during tedious verification of theorem. The simulation results have proved the correctness of system analysis by using such discrimination method under different parameter models.

关键词： state transition matrix simulation experiment homogeneous state equation discrimination

Mosaic of Printed Circuit Board Image Based on Gaussian-Hermite Moment Invariants

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Wuhan University Journal of Natural Sciences 2017年第5期22卷 380-386页

作者： zhang yuye YANG Bo College of Physics and Electronics Engineering Xianyang Normal College School of Automation Northwestern Polytechnical University

Quality inspection of a PCB （Printed Circuit Board） always requires us to stitch some separated images into an integral one. However, during image acquisition, some environmental influences such as vibration, noise and illumination will cause image degradation. An efficient image mosaic method has been urgently required to obtain a high-quality PCB panorama. Hence, an image mosaic method based on Gaussian-Hermite moments is presented in this paper. The characteristic points in the neighborhood of a PCB are represented by Gaussian-Hermite moment in- variants. They are characterized by independence to translation or rotation transformations. Meanwhile, such feature representation shows better noise robustness. Experimental results show that the proposed method produces a qualified mosaic of PCB image.

关键词： image processing template matching Gaussian-Hermite moment invariants image mosaic

Dynamic response of precast segmental bridge columns under heavy truck impact

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Frontiers of Structural and Civil Engineering 2023年第3期17卷 327-349页

作者： yuye zhang Mingli HU Wei FAN Daniel DIAS-DA-COSTA Department of Civil Engineering Nanjing University of Science and TechnologyNanjing 210094China Research Institute of Hunan University in Chongqing Chongqing 401120China Key Laboratory for Wind and Bridge Engineering of Hunan Province Hunan UniversityChangsha 410082China School of Civil Engineering The University of SydneySydneyNSW 2006Australia

Considering the wide application of precast segmental bridge columns(PSBCs)in engineering practice,impact-resistant performance has gained significant ***,few studies have focused on PSBCs subjected to high-energy impacts caused by heavy truck ***,the behavior of PSBCs under a heavy truck impact was investigated in this study using high-fidelity finite element(FE)*** detailed FE modeling methods of the PSBCs and heavy trucks were validated against experimental *** validated modeling methods were employed to simulate collisions between PSBCs and heavy *** simulation results demonstrated that the engine and cargo caused two major peak impact forces during ***,the impact force,failure mode,displacement,and internal force of the PSBCs under heavy truck impacts were *** extensive study was performed to assess the influence of the section size,truck weight,impact velocity,and number of precast segments on the impact *** truck weight was found to have a minor effect on the engine impact *** was found to be localized at the bottom of the three segments,with the top remaining primarily *** parametric study demonstrated that larger cross-sections may be a preferred option to protect PSBCs against the impact of heavy trucks.

关键词： precast segmental bridge columns heavy truck collision dynamic response

Explosion resistance performance of reinforced concrete box girder coated with polyurea:Model test and numerical simulation

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Defence Technology（防务技术） 2024年第3期33卷 1-18页

作者： Guangpan Zhou Rong Wang Mingyang Wang Jianguo Ding yuye zhang School of Science Nanjing University of Science and TechnologyNanjing 210094JiangsuChina School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina State Key Laboratory of Explosion and Impact and Disaster Prevention and Mitigation Army Engineering University of PLANanjing 210007JiangsuChina

To study the anti-explosion protection effect of polyurea coating on reinforced concrete box girder,two segmental girder specimens were made at a scale of 1:3,numbered as G(without polyurea coating)and PCG(with polyurea coating).The failure characteristics and dynamic responses of the specimens were compared through conducting explosion *** reliability of the numerical simulation using LS-DYNA software was verified by the test *** effects of different scaled distances,reinforcement ratios,concrete strengths,coating thicknesses and ranges of polyurea were *** results show that the polyurea coating can effectively enhance the anti-explosion performance of the *** top plate of middle chamber in specimen G forms an elliptical penetrating hole,while that in specimen PCG only shows a very slight local *** peak vertical displacement and residual displacement of PCG decrease by 74.8% and 73.7%,respectively,compared with those of specimen *** the TNT explosion with small equivalent,the polyurea coating has a more significant protective effect on reducing the size of *** the increase of TNT equivalent,the protective effect of polyurea on reducing girder displacement becomes more *** optimal reinforcement ratio,concrete strength,thickness and range of polyurea coating were also drawn.

关键词： Explosive load Explosion resistance performance Model test Polyurea Concrete box girder Numerical simulation

Promoting condensation kinetics of polymeric carbon nitride for enhanced photocatalytic activities

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Chinese Chemical Letters 2020年第1期31卷 115-118页

作者： Dongya Ni yuye zhang Yanfei Shen Songqin Liu Yuanjian zhang Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical ResearchSchool of Chemistry and Chemical EngineeringMedical SchoolSoutheast University

Polymeric carbon nitride(CN)semiconductor by thermal condensation of N-rich precursors has attracted much attention for its capability ranging from photocatalytic and photoelectrochemical energy conversion to ***,the influence of condensation process on the final structure of CN was rarely studied,making the condensation kinetic far from be fully ***,we report the preparation of CN by a simple condensation kinetics modulation using a faster ramping rate during the polymerization *** modified condensation recipe was even simpler than the conventional one,but led to an improved photocatalytic H2 evolution up to 3 times without any additional chemicals or other *** mechanism studies revealed the increase of crystallinity and surface area due to the rapid condensation played the key *** work would offer a more facile and effective way to prepare bulk CN for large-scale industrial applications of bulk CN with higher photocatalytic actives for sustainable energy,environmental and biosensing.

关键词： Polymeric carbon nitride Condensation kinetics Fast ramping rate High crystallinity Photocatalytic hydrogen evolution

Motion-Blurred Image Restoration Based on Joint Invertibility of PSFs

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Computer Systems Science & Engineering 2021年第2期36卷 407-416页

作者： yuye zhang Jingli Huang Jiandong Liu Hakeel Ahmed Chohan Qingdao Branch Navy Aeronautical and Astronautical UniversityQingdao266041China Dazzle Color Flower Core Speech Training School Qingdao266041China

To implement restoration in a single motion blurred image,the PSF(Point Spread Function)is difficult to estimate and the image deconvolution is ill-posed as a result that a good recovery effect cannot be *** that several different PSFs can get joint invertibility to make restoration wellposed,we proposed a motion-blurred image restoration method based on joint invertibility of PSFs by means of computational ***,we designed a set of observation device which composed by multiple cameras with the same parameters to shoot the moving target in the same field of view continuously to obtain the target images with the same *** target images have the same brightness,but different exposure time and different motion blur *** is easy to estimate the blur PSFs of the target images make use of the sequence frames obtained by one *** to the motion blur superposition feature of the target and its background,the complete blurred target images can be extracted from the observed images ***,for the same target images with different PSFs,the iterative restoration is solved by joint solution of multiple images in spatial *** experiments showed that the moving target observation device designed by this method had lower requirements on hardware conditions,and the observed images are more convenient to use joint-PSF solution for image restoration,and the restoration results maintained details well and had lower signal noise ratio(SNR).

关键词： Motion-blurred image restoration PSF invertibility ill-posed problem computational photography

Improved dynamic grey wolf optimizer

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Frontiers of Information Technology & Electronic Engineering 2021年第6期22卷 877-890页

作者： Xiaoqing zhang yuye zhang Zhengfeng MING School of Physics and Electronic Engineering Xianyang Normal UniversityXianyang 712000China School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China

In the standard grey wolf optimizer(GWO), the search wolf must wait to update its current position until the comparison between the other search wolves and the three leader wolves is completed. During this waiting period, the standard GWO is seen as the static GWO. To get rid of this waiting period, two dynamic GWO algorithms are proposed: the first dynamic grey wolf optimizer(DGWO1) and the second dynamic grey wolf optimizer(DGWO2). In the dynamic GWO algorithms, the current search wolf does not need to wait for the comparisons between all other search wolves and the leading wolves, and its position can be updated after completing the comparison between itself or the previous search wolf and the leading wolves. The position of the search wolf is promptly updated in the dynamic GWO algorithms, which increases the iterative convergence rate. Based on the structure of the dynamic GWOs, the performance of the other improved GWOs is examined, verifying that for the same improved algorithm, the one based on dynamic GWO has better performance than that based on static GWO in most instances.

关键词： Swarm intelligence Grey wolf optimizer Dynamic grey wolf optimizer Optimization experiment

Regulation of the density distribution of a strongly dissipative plasma by a pulsed magnetic field

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Plasma Science and Technology 2021年第11期23卷 50-58页

作者： Wenbin LING Chenggang JIN Jian GUAN yuye zhang Peng E School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001People's Republic of China Laboratory for Space Environment and Physical Sciences Harbin Institute of TechnologyHarbin 150001People's Republic of China

A pulsed transverse magnetic field with pulse width of 12 ms and magnitude of 2 T was used to modify the density distribution of a weakly-ionized plasma flow with strong collisions between the charged particles and *** morphology of the plasma is changed substantially,with the density increased upstream and decreased ***,the plasma toward the axis contracts laterally and gradually converges to a collimated *** addition,a drift wave is observed to be excited in the inhomogeneous plasma by the magnetic field.

关键词： pulsed magnetic field weakly-ionized plasma plasma dynamics drift instability

爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤分析

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爆炸与冲击 2019年第3期39卷 141-148页

作者：杨旭张于晔张宁南京理工大学土木工程系江苏南京210094

为研究爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤,采用ANSYS/LS-DYNA建立圆形截面预制节段拼装桥墩受爆的三维实体分离式模型。通过与已有实验结果的对比分析,验证了该模拟方法的可靠性。基于该模型,研究了爆炸冲击作用下节段长... 详细信息

为研究爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤,采用ANSYS/LS-DYNA建立圆形截面预制节段拼装桥墩受爆的三维实体分离式模型。通过与已有实验结果的对比分析,验证了该模拟方法的可靠性。基于该模型,研究了爆炸冲击作用下节段长细比、初始预应力水平及桥墩体系对圆形截面预制拼装桥墩动态响应与损伤的影响规律。结果表明:减小节段长细比使墩身由剪切破坏逐渐变为节段间相对位移,并减小墩身的整体侧向位移;提高初始预应力水平可以在一定程度上提高桥墩的抗爆性能;爆炸冲击作用下混合体系桥墩兼具完全节段和整体现浇桥墩的破坏特征。

关键词：节段拼装桥墩爆炸响应抗爆性能损伤分析