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Associations of preterm and early-term birth with suspected developmental coordination disorder:a national retrospective cohort study in children aged 3-10 years

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World Journal of Pediatrics 2023年第3期19卷 261-272页

作者： Ming-xia liu Hai-Feng Li Mei-Qin Wu Shan-Shan Gengg Li Ke bi-Wen Lou Wenchong Du Jing Hua The Women's and Children's Department Shanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityShanghaiChina Shanghai Key Laboratory of Maternal Fetal Medicine Shanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityShanghaiChina Department of Rehabilitation Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhouChina State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal UniversityBeijingChina Leitontech Research Institution SuzhouChina Department of Psychology NTU PsychologyNottingham Trent UniversityNottinghamUK

Background This study analyzed the motor development and suspected developmental coordination disorder of very and moderately preterm(0.05).Conclusions Our findings have important implications for understanding motor impairment in children born at different gestational *** and moderately preterm preschoolers have an increased risk of DCD,and long-term follow-up should be provided for early detection and intervention.

关键词： China Early-term and preterm birth Late motor impairment Movement Assessment Battery-2 for Children

Remarks on BCOV invariants and degenerations of Calabi-Yau manifolds

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Science China Mathematics 2019年第1期62卷 171-184页

作者： Kefeng liu Wei xia Department of Mathematics Capital Normal University Department of Mathematics University of California at Los Angeles Center of Mathematical Sciences Zhejiang University

For a one parameter family of Calabi-Yau threefolds, Green et al.(2009) expressed the total singularities in terms of the degrees of Hodge bundles and Euler number of the general fiber. In this paper,we show that the total singularities can be expressed by the sum of asymptotic values of BCOV(BershadskyCecotti-Ooguri-Vafa) invariants, studied by Fang et al.(2008). On the other hand, by using Yau's Schwarz lemma, we prove Arakelov type inequalities and Euler number bound for Calabi-Yau family over a compact Riemann surface.

关键词： BCOV invariants Calabi-Yau manifolds singularities Arakelov inequalities

Experimental study on flow excursion instability of supercritical hydrocarbon fuel in scramjet regenerative cooling parallel channels

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Chinese Journal of Aeronautics 2023年第1期36卷 201-215页

作者： xiaoyong liu Zhuqiang YANG Ruipu MIAO Feng liu Shujun ZHAO Qincheng bi Beijing Power Machinery Research Institute Beijing 100074China Liaoning Key Laboratory of Complex Energy Conversion and Utilization School of Energy and Power EngineeringDalian University of TechnologyDalian 116024China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

Flow instability of supercritical hydrocarbon fuel is a crucial issue in scramjet regenerative cooling structure. In this study, flow excursion instability and flow distribution in parallel tubes were experimentally studied for supercritical fluids. Two types of flow excursion occur in a single tube. Type Ⅰ and Type Ⅱ excursions, and they are corresponding to decreasing and increasing flow rate respectively. They can trigger flow maldistribution between parallel tubes and the hysteresis phenomenon of flow distribution. The effects of system parameters, including inlet temperature,system pressure, and heat flux, on flow distribution were analyzed. In addition, the relationship between flow excursion and the pseudo-critical interval proposed in the literature was established according to the heated tube outlet temperature at the onset of flow instability. Finally, the flow excursion instability boundary was obtained using two dimensionless parameters. These experimental results can provide helpful insight on the mechanism of Scramjet regenerative cooling.

关键词： Flow distribution Ledinegg instability Onset of flow excursion Parallel channels Regenerative cooling Scramjet Supercritical flow

Design and performance analysis of networked control systems with random delay

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Journal of Systems Engineering and Electronics 2009年第4期20卷 807-822页

作者： xia Yuanqing Fu Mengyin liu Bo liu Guoping Dept. of Automatic Control Beijing Inst. of Technology Beijing 100081 P. R. China Dept. of Engineering Univ. of Glamorgan Pontypridd CF37 1DL U. K.

The design and performance analysis of networked control systems with random network delay in the forward channel is proposed, which are described in a state-space form. A new control scheme is used to overcome the effects of network transmission delay, which is termed networked predictive control （NPC）. Furthermore, three different ways to choose control input are discussed and the performances are analyzed, respectively. Both real-time simulations and practical experiments show the effectiveness of the control scheme.

关键词： networked control system. Dredictive control random network delay stability

The gap-free genome of mulberry elucidates the architecture and evolution of polycentric chromosomes

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Horticulture Research 2023年第7期10卷 221-232页

作者： bi Ma Honghong Wang Jingchun liu Lin Chen xiaoyu xia Wuqi Wei Zhen Yang Jianglian Yuan Yiwei Luo Ningjia He State Key Laboratory of Resource Insects Southwest UniversityChongqing400715China

Mulberry is a fundamental component of the global sericulture industry,and its positive impact on our health and the environment cannot be ***,the mulberry reference genomes reported previously remained unassembled or unplaced ***,we report the assembly and analysis of the telomere-to-telomere gap-free reference genome of the mulberry species,Morus notabilis,which has emerged as an important reference in mulberry gene function research and genetic *** mulberry gap-free reference genome produced here provides an unprecedented opportunity for us to study the structure and function of *** results revealed that all mulberry centromeric regions share conserved centromeric satellite repeats with different ***,we found that *** is a species with polycentric chromosomes and the only reported polycentric chromosome species up to *** propose a compelling model that explains the formation mechanism of new centromeres and addresses the unsolved scientific question of the chromosome fusion-fission cycle in mulberry *** study sheds light on the functional genomics,chromosome evolution,and genetic improvement of mulberry species.

关键词： evolution free mulberry

Moments of the maximum of normed partial sums of ρ^--mixing random variables

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Applied Mathematics(A Journal of Chinese Universities) 2009年第3期24卷 355-360页

作者： liu xiang-dong liu Jin-xia Dept. of Statist. Jinan Univ. Guangzhou 510630 China

Let {Xn,n ≥ 1} be a sequence of identically distributed ρ^--mixing random variables and set Sn =∑i^n=1 Xi,n ≥ 1,the suffcient and necessary conditions for the existence of moments of supn≥1 ｜Sn/n^1/r｜^p（0 〈 r... 详细信息

关键词： moment of supremum of normed partial sum ρ^--mixing random variable

Dynamics of ionisation wave propagation in an applied external electric field

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High Voltage 2016年第2期1卷 90-94页

作者： Yang xia Dongping liu Hamidreza Ghomi Wenchun Wang Zhenhua bi Longfei Ji Xueyang Wang Zhihua Qi bin Li Liaoning Key Laboratory of Optoelectronic Films and Materials School of Physics and Materials EngineeringDalian Nationalities UniversityDalian 116600People’s Republic of China School of Physics and Optoelectronic Technology Dalian University of TechnologyDalian 116024People’s Republic of China Laser and Plasma Research Institute Shahid Beheshti UniversityEvinTehran ***Iran Beijing Guangyao Energy Technology Co. LtdBeijing 100015People’s Republic of China

This study presents spatio-temporal development of the ionisation waves(IWs)along one dielectric tube with an extra alternating electric field.A pulsed direct current power supply is used for generating the IWs,and another alternating current power supply is used for altering the distribution of electric fields along the dielectric *** measurements show that the propagation velocity and density of IWs are strongly affected by the external electric *** direct relation between external electric field and the velocity of the IWs is *** analysis indicates that the external electric field can be utilised to control the propagation of the IWs,resulting in a change of their density and velocity.

关键词： field. propagation dielectric

An Information Fusion Model of Innovation Alliances Based on the Bayesian Network

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Tsinghua Science and Technology 2018年第3期23卷 347-356页

作者： Jun xia Yuqiang Feng Luning liu Dongjun liu School of Management Harbin Institute of TechnologyHarbin 150001 China. Shenzhen Institute ofElectronics Shenzhen 518055 China

To solve the problem of information fusion from multiple sources in innovation alliances, an information fusion model based on the Bayesian network is presented. The multi-source information fusion process of innovation alliances was classified into three layers, namely, the information perception layer, the feature clustering layer,and the decision fusion layer. The agencies in the alliance were defined as sensors through which information is perceived and obtained, and the features were clustered. Finally, various types of information were fused by the innovation alliance based on the fusion algorithm to achieve complete and comprehensive information. The model was applied to a study on economic information prediction, where the accuracy of the fusion results was higher than that from a single source and the errors obtained were also smaller with the MPE less than 3%, which demonstrates the proposed fusion method is more effective and reasonable. This study provides a reasonable basis for decision-making of innovation alliances.

关键词： information fusion innovation alliance Bayesian networks forecasting model decision making big data

Existence of Solutions for the Critical Elliptic System with Inverse Square Potentials

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Acta Mathematicae Applicatae Sinica 2013年第2期29卷 315-328页

作者： Zhao-xia liu Zhao-hui liu Department of Information and Computational Science School of Sciences Minzu University of China Suncun Middle School Gaoxin District of Jinan

Let Ω∈← 0 be an open bounded domain in RN （N 〉 3） and 2＊（s） = 2（N-8） =2（N-s）N-22. We consider the following elliptic system of two equations in where A, μ 〉 0 and α, β 〉 1 satisfy α ＋ β = 2＊（s... 详细信息

Let Ω∈← 0 be an open bounded domain in RN （N 〉 3） and 2＊（s） = 2（N-8） =2（N-s）N-22. We consider the following elliptic system of two equations in where A, μ 〉 0 and α, β 〉 1 satisfy α ＋ β = 2＊（s）. Using the Moser iteration, we prove the asymptotic behavior of solutions at the origin. In addition, by exploiting the Mountain-Pass theorem, we establish the existence of solutions.

关键词： elliptic system variational functional Palais-Smale condition critical point