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Influence of Pre-strain on the Mechanical Properties of A6111-T4P Sheet with Bake Hardening

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 678-683页

作者： shan-shan Li Jie-Shi Chen jun Chen Cedric Xia Danielle Zeng Institute of Forming Technology and Equipment School of Materials Science and Engineering Shanghai Jiao Tong University Research and Innovation Center Ford Motor Company

A6111 is an aluminum alloy, which exhibits good formability and excellent bake hardening property. This study aimed to reveal the influence of strain path, pre-strain orientation （c0 as well as pre-strain level on the mechanical properties of A6111-T4P sheet under bake treatment through uniaxial tension test. （0-5）% pre-strain, 150-170 ℃ bake temperature and 20-30 min bake time were considered in the study by referring to the actual production process. The results show that both pre-strain level and strain path play significant roles in improving the material properties. In the condition that tensile orientation （β） parallel with pre-strain orientation （β= a）, the yield strength can be remarkably improved, and much higher parameter of n in Hockett-Sherby model can be obtained than those when tensile orientation non-parallel with pre-strain orientation （a≠ β）. In addition, when the pre-strain level, paint bake process were settled and β = a, the curves obtained in five tension orientations are similar in the plastic deformation stage.

关键词： Aluminum alloy Pre-strain Bake hardening Mechanical properties

A fast decoupled ISAR high-resolution imaging method using structural sparse information under low SNR

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Journal of Systems Engineering and Electronics 2019年第3期30卷 492-503页

作者： xiang Long LI Shaodong YANG jun CHEN Wenfeng xiang Hu Department of Air Defense Early Warning Equipment Air Force Early Warning Academy Wuhan 430019 China Unit 93253 of the PLA Dalian 116000 China

Inverse synthetic aperture radar (ISAR) image can be represented and reconstructed by sparse recovery (SR) approaches. However, the existing SR algorithms, which are used for ISAR imaging, have suffered from high computational cost and poor imaging quality under a low signal to noise ratio (SNR) condition. This paper proposes a fast decoupled ISAR imaging method by exploiting the inherent structural sparse information of the targets. Firstly, the ISAR imaging problem is decoupled into two sub-problems. One is range direction imaging and the other is azimuth direction focusing. Secondly, an efficient two-stage SR method is proposed to obtain higher resolution range profiles by using jointly sparse information. Finally, the residual linear Bregman iteration via fast Fourier transforms (RLBI-FFT) is proposed to perform the azimuth focusing on low SNR efficiently. Theoretical analysis and simulation results show that the proposed method has better performence to efficiently implement higher-resolution ISAR imaging under the low SNR condition.

关键词： sparse recovery inverse synthetic aperture radar (ISAR) imaging high-resolution signal to noise ratio (SNR) structural sparse information

CT和MRI评估口腔癌下颌骨受累的临床对研究

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中国CT和MRI杂志 2025年第1期23卷 33-34页

作者：王珊孙翔宇白阳哈尔滨医科大学附属第一医院口腔颌面外科一病房黑龙江哈尔滨150001

目的本研究旨在评价计算机断层扫描(CT)和磁共振成像(MRI)在口腔鳞状细胞癌下颌骨侵犯中的诊断价值,以期为临床诊治提供参考。方法对98例口底、下牙槽、磨牙后三角区鳞状细胞癌患者的临床资料进行回顾性分析。术前CT和MRI扫描由一名... 详细信息

目的本研究旨在评价计算机断层扫描(CT)和磁共振成像(MRI)在口腔鳞状细胞癌下颌骨侵犯中的诊断价值,以期为临床诊治提供参考。方法对98例口底、下牙槽、磨牙后三角区鳞状细胞癌患者的临床资料进行回顾性分析。术前CT和MRI扫描由一名专科医师复查,原始组织由3名病理学家复查。结果45例患者进入最终研究。CT和MRI联合诊断的敏感性为100%,特异性为72%。结论 CT和MRI联合检查对口腔癌侵犯下颌骨有一定的诊断价值,但假阳性率较高。

关键词：计算机断层扫描磁共振成像口腔鳞状细胞癌下颌骨侵犯

Embryonic Growth and Yolk Depletion during Incubation in the Chinese Skink, Plestiodon chinensis

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Asian Herpetological Research 2019年第1期10卷 56-61页

作者： Li MA Kun GUO shan SU xiang JI Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life Sciences Nanjing Normal University

We collected 24 gravid female Chinese skinks(Plestiodon chinensis) to study embryonic growth and yolk depletion during incubation. Females laid eggs between late May and mid-june. Eggs were incubated at 24(± 0.3) ℃. One egg from each clutch was dissected at 5-d intervals starting at laying. Embryonic stages at laying varied from Dufaure and Hubert's(1961) Stage 30-35, with a mean stage of 32.6. Incubation lengths at 24 ℃ varied from 35.1 to 48.3 d, with a mean of 41.5 d. Based on the derived functions describing instantaneous changes in embryo dry mass and yolk dry mass, we identified three phases of embryonic growth or yolk depletion in P. chinensis. Phase 1, from Day 0(at laying) to Day 15(～36% of the way through incubation), was one of minimal transfer of material from yolk to embryo. Phase 2, from Day 15 to Day 32-33(～77%-80% of the way through incubation), was characterized by increasingly rapid embryonic growth or yolk depletion. Phase 3, from Day 32-33 to hatching, was characterized by reduced embryonic growth or yolk depletion. The length of the last embryonic stage(Stage 40 = completely differentiated embryos) accounted for about 28% of incubation length, and the dry mass of the smallest embryos of Stage 40 accounted for only ～48% of the hatchling dry mass. Our study adds evidence to the idea that oviposition is not timed to coincide with the onset of rapid embryonic growth in oviparous reptiles, and is first to demonstrate that ～50% embryonic growth occurs in the last quarter of incubation in P. chinensis.

关键词： egg incubation embryonic growth embryonic stage Plestiodon chinensis scincid lizard yolk depletion

Photocatalyst-controlled and visible light-enabled selective oxidation of pyridinium salts

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Science China Chemistry 2021年第5期64卷 753-760页

作者： xiang-jun Peng Hai-Ping He Qian Liu Kun She Bao-Qi Zhang Heng-shan Wang Hai-Tao Tang Ying-Ming Pan State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal UniversityGuilin 541004China Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases of Ministry of Education Gannan Medical UniversityGanzhou 341000China

This study proposes two different methods of photocatalytic-controlled and visible light-induced selective oxidation of pyridiniums with air as the terminal *** key to these transformations is to choose the appropriate light source and *** are successfully converted into pyrroles through oxygen-mediated cycloaddition,proton-coupled electron transfer(PCET),pyridine ring opening,and *** other route is that pyridiniums selectively form 4-carbonyl pyridines through free radical rearrangement/aerobic oxidation under the catalysis of cobalt(Ⅱ).

关键词： photocatalytic-controlled reaction proton-coupled electron transfer ring opening/recyclization process rearrangement/aerobic oxidation the Ladenburg rearrangement pyridinium

A Real-Time Multi-Stage Architecture for Pose Estimation of Zebrafish Head with Convolutional Neural Networks

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Journal of Computer Science & Technology 2021年第2期36卷 434-444页

作者： Zhang-Jin Huang xiang-xiang He Fang-jun Wang Qing Shen School of Computer Science and Technology University of Science and Technology of ChinaHefei 230027China School of Data Science University of Science and Technology of ChinaHefei 230027China Anhui Province Key Laboratory of Software in Computing and Communication Hefei 230027China

In order to conduct optical neurophysiology experiments on a freely swimming zebrafish,it is essential to quantify the zebrafish head to determine exact lighting *** efficiently quantify a zebrafish head's behaviors with limited resources,we propose a real-time multi-stage architecture based on convolutional neural networks for pose estimation of the zebrafish head on *** stage is implemented with a small neural ***,a light-weight object detector named Micro-YOLO is used to detect a coarse region of the zebrafish head in the first *** the second stage,a tiny bounding box refinement network is devised to produce a high-quality bounding box around the zebrafish ***,a small pose estimation network named tiny-hourglass is designed to detect keypoints in the zebrafish *** experimental results show that using Micro-YOLO combined with RegressNet to predict the zebrafish head region is not only more accurate but also much faster than Faster R-CNN which is the representative of two-stage *** with DeepLabCut,a state-of-the-art method to estimate poses for user-defined body parts,our multi-stage architecture can achieve a higher accuracy,and runs 19x faster than it on CPUs.

关键词： convolutional neural network pose estimation real-time zebrafish

Impacts of Land Use and Cover Change on Land Surface Temperature in the Zhujiang Delta

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Pedosphere 2006年第6期16卷 681-689页

作者： QIAN Le-xiang CUI Hai-shan CHANG Jie School of Geographical Sciences Guangzhou University Guangzhou 510006China College of Environment ＆ Planning Henan University Kaifeng 475004China program in Geographic Information Sciences University of Texas at Dallas Richardson TX 75083 USA

Remote sensing and geographic information systems (GIS) technologies were used to detect land use/cover changes (LUCC) and to assess their impacts on land surface temperature (LST) in the Zhujiang Delta. Multi-temporal Landsat TM and Landsat ETM+ data were employed to identify patterns of LUCC as well as to quantify urban expansion and the associated decrease of vegetation cover. The thermal infrared bands of the data were used to retrieve LST. The results revealed a strong and uneven urban growth,which caused LST to raise 4.56℃in the newly urbanized part of the study area. Overall, remote sensing and GIS technologies were effective approaches for monitoring and analyzing urban growth patterns and evaluating their impacts on LST.

关键词： land surface temperature land use/cover change Landsat ETM+ Landsat TM Zhujiang Delta

Comparison of nonclassicality between photon-added and photon-subtracted squeezed vacuum states

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Chinese Physics B 2012年第2期21卷 301-308页

作者： Ma shan-jun Luo Wen-Wei College of Physics and Communication Electronics Jiangxi Normal UniversityNanchang 330022China

In this paper, we introduce photon-added and photon-subtracted squeezed vacuum state （PASV and PSSV） and obtain their normalized factors, which have the similar forms involved in Lengendre polynomials. Moreover, we give the compact expressions of Wigner function, which are related to single-variable Hermite polynomials. Especially, we compare their nonclassicality in terms of Mandel Q-factor and the negativity of Wigner function.

关键词： photon-added and photon-subtracted squeezed vacuum state nonclassicality Wigner function

High-Order Hamilton's Principle and the Hamilton's Principle of High-Order Lagrangian Function

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Communications in Theoretical Physics 2008年第2期49卷 297-302页

作者： ZHAO Hong-Xia MA shan-jun College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China

In this paper, based on the theorem of the high-order velocity energy, integration and variation principle, the high-order Hamilton＇s principle of general holonomic systems is given. Then, three-order Lagrangian equations and four-order Lagrangian equations are obtained from the high-order Hamilton＇s principle. Finally, the Hamilton＇s principle of high-order Lagrangian function is given.

关键词： Hamilton's principle high-order velocity energy integration and variation principle Lagrangian function