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Differential quadrature time element method for structural dynamics

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Acta Mechanica Sinica 2012年第3期28卷 782-792页

作者： Yu-Feng Xing Jing guo The Solid Mechanics Research Center Beihang University100191 BeijingChina

An accurate and efficient differential quadrature time element method （DQTEM） is proposed for solving ordi- nary differential equations （ODEs）, the numerical dissipation and dispersion of DQTEM is much smaller than that of the direct integration method of single/multi steps. Two methods of imposing initial conditions are given, which avoids the tediousness when derivative initial conditions are imposed, and the numerical comparisons indicate that the first method, in which the analog equations of initial displacements and velocities are used to directly replace the differential quadra- ture （DQ） analog equations of ODEs at the first and the last sampling points, respectively, is much more accurate than the second method, in which the DQ analog equations of initial conditions are used to directly replace the DQ analog equations of ODEs at the first two sampling points. On the contrary to the conventional step-by-step direct integration schemes, the solutions at all sampling points can be obtained simultaneously by DQTEM, and generally, one differential quadrature time element may be enough for the whole time domain. Extensive numerical comparisons validate the effi- ciency and accuracy of the proposed method.

关键词： Differential quadrature rule Direct integrationmethod Time element Phase error. Artificial damping

An unscented particle filter for ground maneuvering target tracking

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1588-1595页

作者： guo Rong-hua QIN Zheng Department of Computer Science and Technology Tsinghua University Beijing 100084 China

In this study, an unscented particle filtering method based on an interacting multiple model (IMM) frame for a Markovian switching system is presented. The method integrates the multiple model (MM) filter with an unscented particle filter (UPF) by an interaction step at the beginning. The framework (interaction/mixing, filtering, and combination) is similar to that in a standard IMM filter, but an UPF is adopted in each model. Therefore, the filtering performance and degeneracy phenomenon of particles are improved. The filtering method addresses nonlinear and/or non-Gaussian tracking problems. Simulation results show that the method has better tracking performance compared with the standard IMM-type filter and IMM particle filter.

关键词： Interacting multiple model (IMM) Unscented particle filter (UPF) Ground target tracking Particle filter (PF)

GLOBAL SUPERCONVERGENCES OF THE DOMAIN DECOMPOSITION METHODS WITH NONMATCHING GRIDS

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Journal of Computational Mathematics 2001年第2期19卷 187-194页

作者： Ping Luo guo-ping Liang Department of Computer Science Tsinghua UniversityBeijing 100084China Institute of Mathematics Academy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100080China

Focuses on a study which determined the use of the global convergences of the domain decomposition methods with Lagrangian multiplier and nonmatching grids in solving the second order elliptic boundary value problems. Background on domain decomposition and global superconvergence; Correction scheme and estimates; Numerical examples.

关键词： domain decomposition defect correction global superconvergence nonmatching grids

Tomato SlRUP is a negative regulator of UV-B photomorphogenesis

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Molecular Horticulture 2021年第1期1卷 108-111页

作者： Chunli Zhang Qianwen Zhang Hongye guo Xiaohui Yu Wenjing Liang Yinhua Chen Ruohe Yin Li lin School of Agriculture and Biology Shanghai Jiao Tong University800 Dongchuan RDMinhang DistrictShanghai 200240People’s Republic of China Key Laboratory of Urban Agriculture(Ministry of Agriculture)and Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource Hainan UniversityHaikou 570228People’s Republic of China

Introduction Sunlight is an environmental factor regulating plant growth and *** have evolved a battery of photoreceptors to sense and respond to different wavelengths of light(Jenkins,2017;Liu et al.,2020a).UV-B(280–315 nm)comprises the shortest wavelength of sunlight on the earth *** general,low fluence rate UV-B does not generate damage effects on plants,rather it induces plant photomorphogenic responses(Yin and Ulm,2017).High fluence rate UV-B may damage macromolecules,including nucleic acids,protein and membranes(Hideg et al.,2013).The UV-B photoreceptor UVR8 protein((UV RESISTANCE LOCUS 8)perceives the low dose UV-B and triggers UV-B specific signal transduction.

关键词： photoreceptor development. morphogenesis

Novel compound heterozygous GPR56 gene mutation in a twin with lissencephaly:A case report

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World Journal of Clinical Cases 2022年第2期10卷 607-617页

作者： Wen-Xin lin Ying-Ying Chai Ting-Ting Huang Xia Zhang guo Zheng Gang Zhang Fang Peng Yan-Jun Huang Department of Neurology Children’s Hospital of Nanjing Medical UniversityNanjing 210000Jiangsu ProvinceChina Department of Neurology Huashan HospitalFudan UniversityShanghai 200040China

BACKGROUND Lissencephaly(LIS)is a malformation of cortical development with broad gyri,shallow sulci and thickened cortex characterized by developmental delays and ***,20 genes have been implicated in ***,GRP56-related LIS has never been ***56 is considered one of the causative genes for bilateral frontoparietal ***,we report a twin infant with LIS and review the relevant *** twins both carried the novel compound heterozygous GPR56 *** SUMMARY A 5-mo-old female infant was hospitalized due to repeated convulsions for 1 *** patient had a flat head deformity that manifested as developmental delays and a sudden onset of generalized tonic-clonic seizures at 5 mo without any *** electroencephalography was *** magnetic resonance imaging revealed a simple brain structure with widened and thickened gyri and shallow *** white matter of the brain was significantly *** long T1 and T2 signals could be seen around the ventricles,which were expanded,and the extracerebral space was *** testing confirmed that the patient carried the GPR56 gene compound heterozygous mutations c.228delC(p.F76fs)and c.1820_1821delAT(p.H607fs).The unaffected father carried a heterozygous c.1820_1821delAT mutation,and the unaffected mother carried a heterozygous c.228delC *** twin sister carried the same mutations as the *** patient was diagnosed with *** This is the first case report of LIS that is likely caused by mutations of the GPR56 gene.

关键词： Lissencephaly Epilepsy GPR56 mutations Compound heterozygous mutations Case report

Quantum twisted double-slits experiments:confirming wavefunctions'physical reality

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Science Bulletin 2017年第17期62卷 1185-1192页

作者： Zhi-yuan Zhou Zhi-Han Zhu Shi-Long Liu Yin-Hai Li Shuai Shi Dong-Sheng Ding Li-Xiang Chen Wei Gao Guang-Can guo Bao-Sen Shi Wang Da-Heng Collaborative Innovation Center for Science of Quantum Manipulation&Control Heilongjiang Province&Harbin University of Science and TechnologyHarbin 150080China CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China Department of Physics Harbin University of Science and TechnologyHarbin 150080China Department of Physics and Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices Xiamen UniversityXiamen 361005China

Are quantum states real? This most fundamental question in quantum mechanics has not yet been satisfactorily resolved, although its realistic interpretation seems to have been rejected by various delayedchoice experiments. Here, to address this long-standing issue, we present a quantum twisted double-slit experiment. By exploiting the subluminal feature of twisted photons, the real nature of a photon during its time in flight is revealed for the first time. We found that photons' arrival times were inconsistent with the states obtained in measurements but agreed with the states during propagation. Our results demonstrate that wavefunctions describe the realistic existence and evolution of quantum entities rather than a pure mathematical abstraction providing a probability list of measurement outcomes. This finding clarifies the long-held misunderstanding of the role of wavefunctions and their collapse in the evolution of quantum entities.

关键词： Orbital angular momentum Subluminal group velocity Double slitsWave functions Physical reality

Effects of air relief openings on the mitigation of solitary wave forces on bridge decks

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Journal of Hydrodynamics 2019年第3期31卷 594-602页

作者： Sheng-chao Xiao An-xin guo Ministry-of-Education Key Laboratory of Structural Dynamic Behavior and Control School of Civil Engineering Harbin Institute of Technology Harbin 150090 China Department of Civil Engineering The University of Queensland Brisbane 4072 Australia

For inverted T-type bridge decks, the air entrapped in the chambers between adjacent girders could increase the wave forces and lead to the destruction of the bridge decks. This paper studies the effects of the air relief openings (ARO) on the mitigation of the solitary wave-induced forces on the bridge decks. Hydrodynamic experiments are conducted for three inverted T-type decks with four, five, and six girders with different wave properties and deck clearances. The open source computational fluid dynamics toolbox OpenFOAM is adopted to conduct numerical simulations for the effects of the AROs. Since the numerical results correlate well with the measurements, the mechanism of the wave-structure interaction can be revealed by the numerical flow fields. Furthermore, the relationship between the shape and the volume of the ARO and the wave forces on the bridge decks, as well as the contribution of each ARO to the effect of the wave force mitigation, is also obtained from the numerical results of the OpenFOAM. Experimental and numerical results demonstrate that the AROs could effectively reduce the vertical wave forces on the bridge decks. The effects of the AROs increase with the increase of the volume of the ARO, while the shape of the ARO has no effect on the reduction of the wave forces.

关键词： Air entrapped hydrodynamic experiment solitary wave forces bridge decks OpenFOAM

Bilateral and symmetric C1-C2 dumbbell ganglioneuromas associated with neurofibromatosis type 1: A case report

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World Journal of Clinical Cases 2019年第1期7卷 109-115页

作者： Chun-Yu Tan Jia-Wei Liu Yi lin Xin-Xin Tie Peng Cheng Xue Qi Yue Gao Zong-Ze guo Department of Neurosurgery The First Hospital of China Medical University X-ray Department The First Hospital of China Medical University Department of Pathology The First Hospital of China Medical University

BACKGROUND Ganglioneuroma(GN) is a rare and benign tumor that originates from autonomic nervous system ganglion cells. The most frequently involved sites are the posterior mediastinum, the abdominal cavity, and the retroperitoneal space. It rarely occurs in the cervical area, compressing the spinal cord. Neurofibromatosis type 1(NF-1) is an autosomal dominant inheritance disorder, whose prevalence rate approximates one per *** SUMMARY We report an extremely rare case of bilateral and symmetric dumbbell GNs of the cervical spine with NF-1. A 27-year-old man with NF-1 presented with a one-year history of gradually progressive right upper extremity weakness and numbness in both hands. Magnetic resonance imaging showed bilateral and symmetric dumbbell lesions at the C1-C2 levels compressing the spinal cord. We performed total resection of bilateral tumors, and the postoperative histopathological diagnosis of the resected mass was GN. After operation, the preoperative symptoms were gradually relieved without complications. To our knowledge,this is the sixth report of cervical bilateral dumbbell *** In some cases, cervical bilateral dumbbell GNs could be associated with *** exact diagnosis cannot be obtained before operation, and pathological outcome is the current gold standard. Surgical resection is the most effective option, and disease outcome is generally good after treatment.

关键词： Ganglioneuroma Cervical Bilateral Dumbbell Surgery Case report

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冷战初期英国政府对南沙问题的讨论及立场

太平洋学报 2018年第10期26卷 91-102页

作者：郭渊暨南大学广东广州510632

20世纪50年代南沙争议凸显之时,英国政府内部讨论了在历史上与其有一定关联的南威岛和安波沙洲如何应对问题,然而一致意见是因法理依据薄弱而导致"主权"主张失效,此立场在对外交往中亦有所表述。为应对南沙问题,英国政府一方面既不承认... 详细信息

20世纪50年代南沙争议凸显之时,英国政府内部讨论了在历史上与其有一定关联的南威岛和安波沙洲如何应对问题,然而一致意见是因法理依据薄弱而导致"主权"主张失效,此立场在对外交往中亦有所表述。为应对南沙问题,英国政府一方面既不承认他方的南沙主权主张,也不公开放弃对两岛屿的声索;另一方面对南沙纷争持中立、不介入立场,然而在实际分析问题时有对两群岛属于中国的默认,并质疑南越、菲律宾提出的主张。在东南亚力量日渐式微的背景下,加之考虑到在南沙无实在的地缘利益,英国政府选择逐渐淡出争议舞台。英国政府相关部门对南沙某些情报的搜集和分析,能为客观认识南海局势的变化,以及他方立场提供一定参照。与美国的遏制战略不同,英国基于实际的地缘政治考虑而决定南海立场,这反映出其南海决策的自主性。

关键词：南沙群岛英国政府主权归属