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Stabilization　Variable　Structure　Control　for　Singular　Decoupling　Motor　System

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Journal of Systems Engineering and Electronics 1997年第1期8卷 65-72页

作者： Zou, Wenxun liu, yongqing SCUT Guangzhou China

This paper describes the important application of variable structure control (VSC) theory on induction motor (IM) decoupling control system. A design scheme using singular system variable structure control method for a decoupling IM system is presented. The scheme is shown to be robust to parametric variations and external disturbances. Simulation results show the stability and effectiveness of the proposed scheme

关键词： Singular system Sliding mode Variable structure control Decoupling control Switch- ing function.

Cell-based therapies for age-related macular degeneration:cell replacement versus paracrine effects

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Neural Regeneration Research 2021年第6期16卷 1214-1215页

作者： Xiaoyan Peng Ling Gao yongqing liu Department of Ophthalmology Beijing Tongren HospitalCapital Medical UniversityBeijingChina Department of Ophthalmology Second Affiliated Hospital of Xiangya Medical SchoolCentral South China UniversityChangshaHunan ProvinceChina James Graham Brown Cancer Center Department of Ophthalmology and Visual SciencesBirth Defects CenterUniversity of Louisville School of MedicineLouisvilleKYUSA

Age-related macular degeneration(AMD)is a leading cause for severe visual loss and legal blindness in seniors *** molecular basis for the disease remains poorly understood,likely involving genetic and environment-related ocular *** pathogenesis proceeds slowly,started with deposits of fatty proteins(drusen)in the Bruch’s membrane,followed by gradual impairments of the posterior choriocapillaris and the anterior retinal pigment epithelium(RPE),and lead to irreversible degeneration of the light receiving neurons(photoreceptor)and vision ***,AMD is divided into two subgroups:dry or atrophy form and wet or exudative *** percent of AMD patients have the wet form.

关键词： degeneration legal irreversible

Natural Gradient Approach to Multichannel Blind Deconvolution

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Journal of Systems Engineering and Electronics 2000年第1期11卷 22-31页

作者： Zhang, Liqing liu, yongqing Li, Yuanqing South China Univ of Technology Guangzhou China

In this paper we study the geometrical structures of FIR filters and their application to multichannel blind deconvolution. First we introduce a Lie group structure and a Riemannian structure on the manifolds of the FIR filters. Then we derive the natural gradients on the manifolds using the isometry of the Riemannian metric. Using the natural gradient, we present a novel learning algorithm for blind deconvolution based on the minimization of mutual information. Some properties of the learning algorithm, such as equivariance and stability are also studied. Finally, the simulations are given to illustrate the effectiveness and validity of the proposed algorithm.

关键词： Communication channels (information theory) Learning algorithms Signal filtering and prediction

On the Lower Cretaceous in Yixian County of Jinzhou City,Western Liaoning,China

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 437-442页

作者： JI Qiang liu yongqing JIANG Xiaojun Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Traditionally, the lacustrine deposits in Yixian County of Western Liaoning have been assigned to either ＂the Dakangpu Bed＂ of the Yixian Formation or the Jiufotang Formation. However,a 206pb/238U age of 126.47±0.87 Ma is newly obtained from the tuff sample （06051） of the lacustrine deposits in the Baitaigou fossil site of Potaizi village, Yixian County, indicating that the lacustrine deposits in Potaizi area are approximately equivalent to the Wumingshan volcanics of the Sihetun Bed of the Yixian Formation in Beipiao. From our new dating data have arisen some new problems： Where could we find the Jiufotang Formation in Yixian County？ How widely distributed is the Jiufotang Formation in Western Liaoning？ Could the traditionally named Jiufotang Formation somewhere in Western Liaoning be the synchronous deposits of other litho-units （e.g. the Yixian Formation） in different facies？ Could some lacustrine deposits somewhere in Western Liaoning have been assigned to the Jiufotang Formation？

关键词： Lower Cretaceous Yixian Formation Jiufotang Formation Yixian County

Neoproterozoic Molar-tooth Structure and Constraint of Depositional Facies and Environment in the North China Platform in Jiangsu, Anhui and Liaoning, Eastern China

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Acta Geologica Sinica(English Edition) 2005年第4期79卷 533-539页

作者： liu yongqing GAO Linzhi liu Yanxue Institute of Geology Chinese Academy of Geological Sciences Beijing 100037

Molar tooth structure （MTS） represented by complex ptygmatical shapes is widely distributed in the Proterozoic of the world. MTS filled by fine, equant sparry calcite （or dolomite） displays an abrupt contact with hosting rocks, which are mainly composed of carbonaceous micrites and fine-grained carbonates with local silts and stormdominated deposits with graded, cross or wave beddings, numerous erosional surfaces and truncated and fills or guttered bases. Occurrence of MTS suggests a result of the constraint of sedimentary facies, and the storm-base in ramp settings is the maximum depth for the formation of MTS. Vertical succession of MTS-bearing carbonates shows a deposition stacked by high-frequency shallow subtidal and peritidal cycles. An individual cyclic MTS-bearing sequence is characterized by thinning, shallowing and dynamic decreasing-upward, and peritidal caps of purple red iron and organic carbonaceous sediments with more complicated shapes of MTS are common on the top of individual MTS-bearing sequences.

关键词： North China Platform Neoproterozoic Molar-tooth structure carbonate facies and environment

LA-ICPMS Zircon U-Pb Dating in the Jurassic Daohugou Beds and Correlative Strata in Ningcheng of Inner Mongolia

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Acta Geologica Sinica(English Edition) 2006年第5期80卷 733-742页

作者： liu Yanxue liu yongqing ZHANG Hong Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 Key Laboratory of Insect Evolution and Environmental Changes Capital Normal University Beijing 100037 Shenyang Institute of Geology and Minerals Resources China Geological Survey Shenyang Liaoning 110032

LA-ICPMS Zircon U-Pb dating is applied to volcanic rocks overlying and underlying the Salamander-bearing bed in the Daohugou beds of Ningcheng in Inner Mongola and Reshuichang of Lingyuan and Mazhangzi of Jianping in western Liaoning. The results indicate that the youngest age of the rocks in Daohugou of Ningcheng is 158 Ma, and the oldest one is 164 Ma. Synthesized researches indicate that the salamander-bearing beds in Daohugou of Ningcheng, Reshuichang of Lingyuan and Mazhangzi of Jianping were developed in the same period. The Daohugou beds were formed in the geological age of 164-158 Ma of the middle-late Jurassic. Whilst, the Daohugou beds and its corrdative strata should correspond to the Tiaojishan Formation （or Lanqi Formation） of the middle Jurassic in northern Hebei Province and western Liaoning Province, based on the disconformity between the Daohugou beds and its overlaying beds of the Tuchengzi Formation of Late Jurassic and the Jehol Beds of early Cretaceous, and the disconformity between the Daohugou Beds and its underlying Jiulongshan Formation, which is composed of conglomerate, sandstone, shale with coal and thin coal beds.

关键词： Inner Mongolia Liaoning Daohugou Beds Zircon U-Pb dating LA-ICPMS Tiaojishan Formation Jurassic

Almost periodic solution to singular systems

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Chinese Science Bulletin 1998年第8期43卷 698-700页

作者： Jiarong Liang yongqing liu Cunchen Gao S China Univ Technol Dept Automat Canton 510641 Peoples R China

The problems about the almost periodic solution to singular systems are studied. The criterion that the singular systems have almost periodic solutions is obtained. At the same time, the applied example is given.

关键词： singular systems almost periodic solutions boundary.

Ca. 1.7 Ga Magmatism on Southwestern Margin of the Yangtze Block: Response to the Breakup of Columbia

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 2031-2052页

作者： GENG Yuansheng DU Lilin KUANG Hongwei liu yongqing Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

This paper presents some data of the Jiaopingdu gabbro and Caiyuanzi granite at the southwestern margin of the Yangtze Block,on the geochemical compositions,zircon LA-ICP-MS U-Pb ages and Hf isotopic *** Jiaopingdu gabbro gives the age of 1721±5 Ma,the Caiyuanzi granite 1732±6 Ma and 1735±4 Ma,and the Wenjiacun porphyry granite 1713±4 Ma,suggesting nearly contemporaneous formation time of the gabbro and *** bimodal feature is demonstrated by the gabbro Si O2 content of 44.64-46.87 wt%and granite 73.81-77.03 wt%.In addition,the granite has high content of Si O2 and Na2 O+K2 O,low content of Al2 O3 and Ca O,enriched in REEs(except Eu)and Zr,Nb,Ga and Y,depleted in Sr,implying it belongs to A-type granite geochemistry and origin of within-plate *** zirconε(Hf)(t)of the granite and gabbro is at the range of 2-6,which is near the 2.0 Ga evolution line of the crust,implying the parent magma of the gabbro being derived from the depleted mantle and a small amount of crustal material,and the parent magma of the granite from partial melting of the juvenile crust and some ancient crustal material at the same *** with 1.8-1.7 Ga magmatism during breakup of other cratons in the world,we can deduce that the Columbia has initially broken since ca.1.8 Ga,and some continental marginal or intra-continental rifts occurred at ca.1.73 Ga.

关键词： 1.7 Ga magmatism bimodal intrusions geochemistry and geochronology Columbia supercontinent break-up southwestern margin of Yangtze Block

Transcriptional Analysis of Normal Human Fibroblast Responses to Microgravity Stress

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Genomics, Proteomics & Bioinformatics 2008年第1期6卷 29-41页

作者： yongqing liu Eugenia Wang Department of Biochemistry and Molecular Biology University of Louisville School of Medicine Louisville KY 40202 USA. Current address. James Graham Brown Cancer Center Department of Ophthalmology and Visual SciencesUniversity of Louisville School of Medicine Louisville KY 40202 USA.

To understand the molecular mechanism（s） of how spaceflight affects cellular signaling pathways, quiescent normal human WI-38 fibroblasts were flown on the STS-93 space shuttle mission. Subsequently, RNA samples from the spaceflown and ground-control cells were used to construct two cDNA libraries, which were then processed for suppression subtractive hybridization （SSH） to identify spaceflight-specific gene expression. The SSH data show that key genes related to oxidative stress, DNA repair, and fatty acid oxidation are activated by spaceflight, suggesting the induction of cellular oxidative stress. This is further substantiated by the up-regulation of neuregulin 1 and the calcium-binding protein calmodulin 2. Another obvious stress sign is that spaceflight evokes the Ras/mitogen-activated protein kinase and phosphatidylinositol-3 kinase signaling pathways, along with up-regulating several Gl-phase cell cycle traverse genes. Other genes showing upregulation of expression are involved in protein synthesis and pro-apoptosis, as well as pro-survival. Interactome analysis of functionally related genes shows that c-Myc is the ＂hub＂ for those genes showing significant changes. Hence, our results suggest that microgravity travel may impact changes in gene expression mostly associated with cellular stress signaling, directing cells to either apoptotic death or premature senescence.

关键词： microgravity apoptosis premature senescence oxidative stress subtractive hybridization