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An Algorithm of Deformation Image Correction Based on Spatial Mapping

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Chinese Journal of Electronics 2024年第5期33卷 1326-1336页

作者： Xiangyu DENG Aijia ZHANG Jinhong YE College of physics and Electronic engineering Northwest Normal University

The original image undergoes geometric deformation in terms of position, shape, size, and orientation due to the shooting angle or capturing process during image acquisition. This leads to inconveniences and significant challenges in various image processing fields such as image fusion, denoising, recognition, and segmentation. To enhance the processing ability and recognition accuracy of deformation images, an adaptive algorithm for correcting image deformities is proposed for quadrilaterals and triangles. Firstly, the deformation image undergoes preprocessing, and the contour of the image edge is extracted. Then, discrete points on the image edge are identified to accurately locate the edges. Finally, the deformation of the quadrilateral or triangle is transformed into a standard rectangular or equilateral triangular image using the proposed three-dimensional homography transformation algorithm. This effectively completes the conversion from an irregular image to a regular image in an adaptive manner. Numerous experiments demonstrate that the proposed algorithm surpasses traditional methods like Hough transform and Radon *** improves the effectiveness of correcting deformation in images, effectively addresses the issue of geometric deformation, and provides a new technical method for processing deformation images.

关键词： Image preprocessing Image vertex positioning Three-dimensional space Homography transformation Image correction Image preprocessing Image vertex positioning Three-dimensional space Homography transformation Image correction DISTORTION

Dynamics of 2×2 matrix non-Hermitian quantum systems on Bloch sphere

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Communications in Theoretical physics 2024年第4期76卷 66-71页

作者： Libin Fu Graduate School of China Academy of engineering physics Beijing 100193China

By casting evolution to the Bloch sphere, the dynamics of 2 × 2 matrix non-Hermitian systems are investigated in detail. This investigation reveals that there are four kinds of dynamical modes for such systems. The different modes are classified by different kinds of fixed points, namely,the elliptic point, spiral point, critical node, and degenerate point. The Hermitian systems and the unbroken PT non-Hermitian cases belong to the category with elliptic points. The degenerate point just corresponds to the systems with exceptional point(EP). The topological properties of the fixed point are also discussed. It is interesting that the topological charge for the degenerate point is two, while the others are one.

关键词： non-Hermitian quantum system two-level system dynamics on the Bloch sphere PT-symmetry fixed points

Pipeline thickness estimation using the dispersion of higher-order SH guided waves

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Chinese physics B 2024年第7期33卷 389-396页

作者：代政辰刘金霞龙云飞张建海 Tribikram Kundu 崔志文 department of Acoustics and Microwave physics College of PhysicsJilin UniversityChangchun 130012China School of Mechanical and Aerospace engineering Jilin UniversityChangchun 130025China department of Civil and Architectural engineering and Mechanics University of ArizonaTucsonArizona 85721USA College of Aerospace and Mechanical engineering University of ArizonaTucsonAZ 85721USA State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thickness measurement limits its widespread application. This paper proposes a method that utilizes cylindrical shear horizontal(SH) guided waves to estimate pipeline thickness without prior knowledge of shear wave velocity. The inversion formulas are derived from the dispersion of higher-order modes with the high-frequency approximation. The waveform of the example problems is simulated using the real-axis integral method. The data points on the dispersion curves are processed in the frequency domain using the wave-number method. These extracted data are then substituted into the derived formulas. The results verify that employing higher-order SH guided waves for the evaluation of thickness and shear wave velocity yields less than1% error. This method can be applied to both metallic and non-metallic pipelines, thus opening new possibilities for health monitoring of pipeline structures.

关键词： pipeline wall thickness higher-order modes SH guided waves dispersion

Facile synthesis of nanosized spinel high entropy oxide (FeCoNiCrMn)_(3)O_(4) for efficient oxygen evolution reaction

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Journal of Materiomics 2024年第4期10卷 919-927页

作者： Bomin Feng Jun Chen Yifei Yang Mao Yang Hongbing Wang Changyin Zhong Xiaochong Zhao Yunxi Yao Institute of Materials China Academy of Engineering PhysicsJiangyou621908China

The sluggish reaction kinetics of oxygen evolution reaction(OER)and the high price of noble metal catalysts hinder the wide application of water electrolysis for hydrogen ***-entropy oxides(HEOs)with multi-components and high entropy stabilized structures have attracted great research interests due to their efficient and durable performance in electrolytic water splitting ***,the development of efficient HEO electrocatalysts are often hindered by the limited surface exposed active sites because high temperature is usually required to form a high entropy stabilized ***,a flaky high-entropy oxide with a spinel structure,(FeCoNiCrMn)_(3)O_(4),was synthesized by using the sacrificial layered carbon template in situ prepared by the volatile reaction between ammonium sulfate and molten ***-resolution TEM results show the as-prepared(FeCoNiCrMn)_(3)O_(4) flakes are composed of nanosized HEO *** nanosized(FeCoNiCrMn)_(3)O_(4) HEO electrocatalysts exhibit excellent OER activity,with an overpotential of 239 mV at 10 mA/cm^(2) and a Tafel slope of 52.4 mV/*** electrocatalyst has excellent *** at a high current density of 100 mA/cm^(2),the activity remains unchanged during the stability test for 24 *** results here shed a new light in the design and fabrication of highly efficient HEO electrocatalysts.

关键词： High entropy oxides Oxygen evolution reaction Spinel oxide Millard reaction Electrocatalyst

Residual stress modeling of mitigated fused silica damage sites with CO_(2)laser annealing

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Chinese physics B 2024年第3期33卷 509-514页

作者：张传超廖威张丽娟蒋晓龙方振华蒋晓东 Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China

A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage *** proposed model extracts the residual strain from the differences in thermoelastic contraction of fused silica with different fictive temperatures from the initial frozen-in temperatures to ambient *** residual stress fields of mitigated damage sites for the CO_(2)laser-annealed case are obtained by a finite element analysis of equilibrium equations and constitutive *** simulated results indicate that the proposed model can accurately evaluate the residual stress fields of laser-annealed mitigated damage sites with a complex thermal *** calculated maximum hoop stress is in good agreement with the reported experimental *** estimated optical retardance profiles from the calculated radial and hoop stress fields are consistent with the photoelastic *** results provide sufficient evidence to demonstrate the suitability of the proposed model for describing the residual stresses of mitigated fused silica damage sites after CO_(2)laser annealing.

关键词： fused silica damage mitigation residual stress laser annealing

Simulation of deuterium pellet ablation and deposition in the EAST tokamak with HPI2 code

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Chinese physics B 2024年第4期33卷 561-569页

作者：李大正张洁侯吉磊李懋孙继忠 Key Laboratory of Materials Modification by Laser Ionand Electron BeamsSchool of PhysicsDalian University of TechnologyDalian 116024China department of Plasma physics and Fusion engineering University of Science and Technology of ChinaHefei 230026China Institute of Plasma physics Chinese Academy of SciencesHefei 230031China

Pellet injection is a primary method for fueling the plasma in magnetic confinement *** that goal the knowledges of pellet ablation and deposition profiles are *** the present study,the pellet fueling code HPI2 was used to predict the ablation and deposition profiles of deuterium pellets injected into a typical H-mode discharge on the EAST *** ablation and deposition profiles were evaluated for various pellet injection locations,with the aim at optimizing the pellet injection to obtain a deep fueling *** this study,we investigate the effect of the injection angle on the deposition depth of the pellet at different velocities and *** ablation and deposition of the injected pellet are mainly studied at each injection position for three different injection angles:0°,45°,and 60°.The pellet injection on the high field side(HFS)can achieve a more ideal deposition depth than on the low field side(LFS).Among these angles,horizontal injection on the middle plane is relatively better on either the HFS or the *** the injection location is 0.468 m below the middle plane on the HFS or 0.40 m above the middle plane of the LFS,it can achieve a similar deposition depth to the one of its corresponding *** the pre-cooling effect is taken into account,the deposition depth is predicted to increase only slightly when the pellet is launched from the *** findings of this study will serve as a reference for the update of pellet injection systems for the EAST tokamak.

关键词： pellet injection pellet ablation HPI2 pellet deposition

Room-temperature hydrogen adsorption in Pd nanoparticle decorated UiO-66-NH2 via spillover

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Particuology 2024年第10期93卷 309-315页

作者： Jingchuan Wang Junhong Luo Yong Yao Jiangfeng Song Yan Shi Institute of Materials China Academy of Engineering PhysicsJiangyou621908China

To improve room-temperature hydrogen storage, palladium (Pd) nanoparticles were innovatively decorated by carbon bridge onto the amino-group functioned Zr-terephthalate metal-organic framework (MOF) UiO-66 to reduce the diffusion energy barrier and then improve the hydrogen spillover effect. Powder X-ray diffraction shows broad Pd peak and retained UiO-66-NH_(2) integrity after Pd decoration. The hydrogen uptake capacity show that UiO-66-NH_(2)-Pd exhibits best hydrogen storage performance than UiO-66-NH_(2) and pristine UiO-66. The hydrogen up taken in Pd decorated UiO-66 (UiO-66-NH_(2)-1Pd) was close to 4 wt% under 20 MPa at room temperature. Density functional theory (DFT) calculations show that hydrogen adsorption energy of UiO-66-NH_(2)-Pd was −0.5897 eV, which was much lower than that of UiO-66-NH_(2) (−0.3716 eV) and UiO-66 (−0.2975 eV). Ultimately, Pd decorated NH_(2) group functioned UiO-66 enable improve storage capacities through hydrogen spillover under ambient conditions which could satisfy the demand for sustainable energy, especially for the long-term storage energy media.

关键词： Hydrogen storage UiO-66-NH_(2) Pd decorated Spillover

Dynamics of self-hybridized exciton–polaritons in 2D halide perovskites

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Light(Science & Applications) 2024年第1期13卷 13-22页

作者： Surendra B.Anantharaman Jason Lynch Christopher E.Stevens Christopher Munley Chentao Li Jin Hou Hao Zhang Andrew Torma Thomas Darlington Francis Coen Kevin Li Arka Majumdar PJames Schuck Aditya Mohite Hayk Harutyunyan Joshua R.Hendrickson Deep Jariwala department of Electrical and Systems engineering University of PennsylvaniaPhiladelphiaPA19104USA KBR Inc. BeavercreekOH45431USA Air Force Research Laboratory Sensors DirectorateWright-Patterson Air Force BaseOH45433USA department of physics University of WashingtonSeattleWA98195USA department of physics Emory UniversityAtlantaGA30322USA department of Chemical and Biomolecular engineering Rice UniversityHoustonTX77005USA department of Materials Science and Nanoengineering Rice UniversityHoustonTX77005USA Applied physics Program Smalley‐Curl InstituteRice UniversityHoustonTX77005USA department of Mechanical engineering Columbia UniversityNew YorkNY10027USA department of Electrical and Computer engineering University of WashingtonSeattleWA98195USA

Excitons,bound electron–hole pairs,in two-dimensional hybrid organic inorganic perovskites(2D HOIPs)are capable of forming hybrid light-matter states known as exciton-polaritons(E–Ps)when the excitonic medium is confined in an optical *** the case of 2D HOIPs,they can self-hybridize into E–Ps at specific thicknesses of the HOIP crystals that form a resonant optical cavity with the ***,the fundamental properties of these self-hybridized E–Ps in 2D HOIPs,including their role in ultrafast energy and/or charge transfer at interfaces,remain ***,we demonstrate that>0.5µm thick 2D HOIP crystals on Au substrates are capable of supporting multiple-orders of self-hybridized E–P *** E–Ps have high Q factors(>100)and modulate the optical dispersion for the crystal to enhance sub-gap absorption and *** varying excitation energy and ultrafast measurements,we also confirm energy transfer from higher energy E–Ps to lower energy E–***,we also demonstrate that E–Ps are capable of charge transport and transfer at *** findings provide new insights into charge and energy transfer in E–Ps opening new opportunities towards their manipulation for polaritonic devices.

关键词： charge polar excitation

Edge modes in finite-size systems with different edge terminals

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Chinese physics B 2024年第10期33卷 381-387页

作者： Huiping Wang Li Ren Xiuli Zhang Liguo Qin School of Mathematics Physics and StatisticsShanghai University of Engineering ScienceShanghai 201620China

We investigate the behavior of edge modes in the presence of different edge terminations and long-range(LR)***,we mainly focus on such model crystals with two different types of structures(type I:“…-P-Q-P-Q-…”and type II:“…=P-Q=P-Q=…”),where P and Q represent crystal lines(CLs),while the symbols“-”and“=”denote the distance between the nearest neighbor(NN)*** on the lattice model Hamiltonian with LR hopping,the existence of edge modes is determined analytically by using the transfer matrix method(TMM)when different edge terminals are taken into *** findings are consistent with the numerical results obtained by the exact diagonalization *** also notice that edge modes can exhibit different behaviors under different edge *** result is helpful in solving novel edge modes in honeycomb crystalline graphene and transition metal dichalcogenides with different edge terminals.

关键词： edge modes long-range hopping different edge terminals