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Management characteristics and prognosis after stroke in China:findings from a large nationwide stroke registry

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Stroke & Vascular Neurology 2021年第1期6卷 1-9页

作者： Haiqiang Qin Yiping Chen Gaifen Liu Iain Turnbull Runhua Zhang Zixiao Li Yilong Wang Liping Liu Xingquan Zhao Zhengming Chen Yongjun Wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Center of Stroke Beijing Institute for Brain DisordersBeijingChina beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease BeijingChina Medical Research Council Population Health Research Unit Nuffield Department of Population HealthUniversity of OxfordOxfordUK Clinical Trial Service Unit&Epidemiological Studies Unit Nuffield Department of Population HealthUniversity of OxfordOxfordUK

Background and purpose There is limited nationwide evidence about the standard management characteristics of stroke types and prognosis in *** study aimed to assess clinical characteristics,in-hospital and after-discharge management characteristics and prognosis for stroke types in *** A nationwide registry recruited 14244 imaging-confirmed first-ever incident strokes from 132 hospitals across 31 provinces of China during 2007-2008,recording presenting characteristics,diagnostic procedures and in-hospital *** hospital discharge,patients were followed up for 6 *** statistical methods were used to examine the patterns of management and *** Overall,68.7%,26.9%and 4.4%were ischaemic stroke(IS),intracerebral haemorrhage(ICH),and subarachnoid haemorrhage(SAH),*** 20%were managed in a dedicated stroke *** IS,1.3%received thrombolysis within 3 hours after symptom onset,whereas the proportions of receiving in-hospital antiplatelet therapy,neuroprotective agents and traditional Chinese medicines(TCM)were 88.4%,69.7%and 70.6%,*** ICH,63.3%and 36.3%received neuroprotective agents and TCM in hospital,*** discharge,70.7%and 38.0%of the patients with IS were given antiplatelet and statin therapies,respectively,decreasing to 64.8%and 23.9%,respectively,at 6 ***-hospital mortality was 3.2%,9.3%and 10.1%for IS,ICH and SAH,respectively,with a further 8.6%,18.2%and 22.0%,respectively,died by 6 ***,in-hospital recurrence rate was 2.6%,1.9%and 7.2%for IS,ICH and SAH,respectively,with a further 8.0%,5.1%and 7.5%,respectively,recurred by 6 *** In China,the mortality rate of stroke is lower than that reported from west populations,though most strokes are not managed in specialised stroke *** is widespread use of some unproven therapies but limited proven treatments,especially after discharge,leading to unnecessary recurrent risks.

关键词： protective prognosis mortality

Asymmetric Information, Heterogeneous Prior Beliefs and Market Regulation

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Acta Mathematicae Applicatae Sinica 2021年第3期37卷 459-476页

作者： Hong LIU Ying JIANG Huai-nian ZHANG KLAS and School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024China Department of Mathematics and Physics Beijing Institute of Petrochemical TechnologyBeijing 102617China

This paper studies the trading behavior of an irrational insider and its influence on the market equilibrium in the presence of market *** find that the market with only one insider with private information is almost close to a strong efficient market,under the condition of market *** the equilibrium,the probability of the insider being caught trading with private information is zero,which shows that the reasonable behavior of the regulator is to essentially give up *** the market efficiency and the irrational trader’s trading intensity all greatly improve because of the existence of the market regulation.

关键词： insider trading market regulation heterogeneous prior beliefs asymmetric information

Feature and Tendency of technology Transfer in Z-Park Patent Cooperation Network:From the Perspective of Global Optimal Path

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Journal of Data and Information science 2021年第4期6卷 111-138页

作者： Jun Guan Jingying Xu Yu Han Dawei Wang Lizhi Xing School of Economics and Management Beijing University of TechnologyBeijing 100124China

Purpose:This study aims to provide a new framework for analyzing the path of technology diffusion in the innovation network at the regional level and industrial level respectively,which is conducive to the integration of innovation resources,the coordinated development of innovative subjects,and the improvement of innovation ***/methodology/approach:Based on the Z-Park patent cooperation data,we establish Inter-Enterprise technology Transfer Network model and apply the concept of Pivotability to describe the key links of technology diffusion and quantify the importance of innovative *** measuring the topologically structural characteristics in the levels of branch park and the technosphere,this paper demonstrates how technology spreads and promotes overall innovation activities within the innovation ***:The results indicate that:(1)Patent cooperation network of the Z-Park displays heterogeneity and the connections between the innovative subjects distribute extremely uneven.(2)Haidian park owns the highest pivotability in the IETTN model,yet the related inter-enterprise patent cooperation is mainly concentrated in its internal,failing to facilitate the technology diffusion across multiple branch parks.(3)Such fields as“electronics and information”and“advanced manufacturing”are prominent in the cross-technosphere cooperation,while fields such as“new energy”and“environmental protection technology”can better promote industrial *** limitations:Only the part of the joint patent application is taken into account while establishing the patent cooperation *** other factors that influence the mechanism of technology diffusion in the innovation network need to be further studied,such as financial capital,market competition,and personnel mobility,*** implications:The findings of this paper will provide useful information and suggestions for the administration and policy-making of high-tech ***

关键词： Patent Cooperation Innovation Network Industrial Integration Z-Park

The effect of NDGA-modified etchant on the enzymatic degradation resistance and mechanical properties of collagen matrix

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Chinese Chemical Letters 2018年第1期29卷 205-208页

作者： Shi-Qiang Gong Zhen-Jie Xue Shu-Teng Liao Ya-Bo Wu Yan Liu Center of Stomatology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology beijing National Laboratory for Molecular science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry the Chinese Academy of Sciences Laboratory of Biomimetic Nanomaterials Department of Orthodontics Peking University School and Hospital of Stomatology National Engineering Laboratory for Digital and Material Technology of Stomatology Beijing Key Laboratory of Digital Stomatology

Enzymatic degradation of demineralized collagen matrix seriously impairs durable resin-dentin bonding. In this study, we evaluated the effect of nordihydroguaiaretic acid （NDGA）-modified etchant on the resistance to enzymatic degradation and mechanical properties of demineralized collagen matrix. Dentin beams were randomly demineralized by following solutions： 1 ） 10% phosphoric acid （PhA） solution, 2） 10% dimethyl sulfoxide （DMSO）-PhA solution, 3） NDGA-modified etchant, and 4） proanthocyanidins （PA）-modified etchant. The demineralized dentin collagen was then digested by type l collagenase solution. The collagenase degradation resistance was evaluated by measuring loss of dry mass, hydroxyproline release, and elastic modulus change. The degradation rate and hydroxyproline release of dentin collagen treated with NDGA-modified etchant were significantly lower than those in the other groups （P〈 0.001）. The elastic modulus of dentin beams treated with NDGA-modified etchant did not increase significantly. However, after 48 h of collagenase degradation, the loss of elastic modulus of dentin beams treated with NDGA-modified etchant was significantly lower than that of the control group （P〈 0.001）. The NDGA-modified etchant could improve the resistance to enzymatic degradation of type l collagenase degradation, and the stability of the mechanical properties of dentin collagen. This proof-of-concept study validates the etch-and-crosslink technique that improves durability of dentin bonding through simultaneous dentin etching and collagen crosslinking.

关键词： NDGACrosslinkDegradationMechanical propertiesCollagen

Foundation Treatment in Urban Underground Engineering Using Big Data Analysis for Smart City Applications

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Computer Modeling in Engineering & sciences 2022年第7期132卷 153-172页

作者： Fei Liu Yunkai Zhang Jian Zhang School of Civil and Transportation Engineering Beijing University of Civil Engineering and ArchitectureBeijing102616China beijing Advanced Innovation Center for Future Urban Design Beijing102616China School of science Beijing University of Civil Engineering and ArchitectureBeijing102616China

A core element of the sustainable approach to global living quality improvement can now become the intensive and organized usage of underground *** is a growing interest in underground building and growth *** reduced consumption of electricity,effective preservation of green land,sustainable wastewater and sewage treatment,efficient reverse degradation of the urban environment,and reliable critical infrastructure management can improve the quality of *** the same time,technological innovations such as artificial intelligence(AI),cloud computing(CC),the internet of things(IoT),and big data analytics(BDA)play a significant role in improved quality of ***,this study aims to integrate the technological innovations in urban underground engineering to ensure a high quality of ***,this study uses big data analytics to carry out the status quo of foundation treatment and proposes a conceptual framework named the BDA with IoT on urban underground engineering(BI0T-UUE).This framework connects hidden features with various high-level sensing sources and practical predictive model characterization to lower building costs,productive infrastructure management,preparedness for disasters,and modern community smart *** IoT integration gives an optimum opportunity to work towards the functionality of‘‘digital doubles’’of secret infrastructure,both economical and scalable,with the increasing sophistication and tooling of the *** simulation analysis ensures the highest efficiency and cost-effectiveness of the underground engineering with a value of 96.54%and 97.46%.

关键词： Underground engineering internet of things big data analytics status quo economic and social smart city

Machine-learning-assisted prediction of the mechanical properties of Cu–Al alloy

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 362-373页

作者： Zheng-hua Deng Hai-qing Yin Xue Jiang Cong Zhang Guo-fei Zhang Bin Xu Guo-qiang Yang Tong Zhang Mao Wu Xuan-hui Qu Collaborative Innovation Center of Steel technology University of Science and Technology BeijingBeijing 100083China Chongqing Engineering technology Research Center for Light Alloy and Processing Chongqing Three Gorges UniversityChongqing 404000China beijing Advanced Innovation Center for Materials Genome Engineering Beijing 100083China Institute for Advanced Materials and technology University of Science and Technology BeijingBeijing 100083China

The machine-learning approach was investigated to predict the mechanical properties of Cu–Al alloys manufactured using the powder metallurgy technique to increase the rate of fabrication and characterization of new materials and provide physical insights into their *** algorithms were used to construct the prediction models, with chemical composition and porosity of the compacts chosen as the *** results show that the sequential minimal optimization algorithm for support vector regression with a puk kernel(SMOreg/puk) model demonstrated the best prediction ability. Specifically, its predictions exhibited the highest correlation coefficient and lowest error among the predictions of the six models. The SMOreg/puk model was subsequently applied to predict the tensile strength and hardness of Cu–Al alloys and provide guidance for composition design to achieve the expected values. With the guidance of the SMOreg/puk model, Cu–12Al–6Ni alloy with a tensile strength(390 MPa) and hardness(HB 139) that reached the expected values was developed.

关键词： powder metallurgy tensile strength hardness machine learning Cu–Al alloy SMOreg/puk

BGMM： A Body Gauss-Markov Based Mobility Model for Body Area Networks

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Tsinghua science and technology 2018年第3期23卷 277-287页

作者： Yi Liu Danpu Liu Guangxin Yue School of Information and Communication Engineering Beijing University of Post and TelecommunicationsBeijing 100876 China. Email: mableliuyi@*** School of Information Engineering Beijing Institute of Fashion Technology Beijing 100029China Jacob School University of California SanDiego CA 92122 USA.

Existing mobility models have limitations in their ability to simulate the movement of Wireless Body Area Network（WBAN） since body nodes do not exactly follow either classic mobility models or human contact distributions. In this paper, we propose a new mobility model called Body Gauss–Markov Mobility（BGMM） model,which is oriented specially to WBAN. First, we present the random Gauss-Markov mobility model as the most suitable theoretical basis for developing our new model, as its movement pattern can reveal real human body movements. Next, we examine the transfer of human movement states and derive a simplified mathematical Human Mobility Model（HMM）. We then construct the BGMM model by combining the RGMM and HMM models. Finally,we simulate the traces of the new mobility model. We use four direct metrics in our proposed mobility model to evaluate its performance. The simulation results show that the proposed BGMM model performs with respect to the direct mobility metrics and can effectively represent a general WBAN-nodes movement pattern.

关键词： mobility metric mobility model human movement model random Gauss-Markov Wireless Body Area Network(WBAN)

A Hybrid Aspect Based Latent Factor Model for Recommendation

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Chinese Journal of Electronics 2020年第3期29卷 482-490页

作者： YUAN Hanning CHEN Zhengyu YANG Jingting WANG Shuliang GENG Jing KE Chuwen School of Computer science & technology Beijing Institute of Technology

Recommender system has been recognized as a superior way for solving personal information overload problem. More and more aspect-based models are leveraging user ratings and extracting information from review texts to support recommendation. Aspect-based latent factor model predicts user ratings relying on latent aspect inferred from user reviews. It usually constructs only a single global model for all users, which may be not sufficient to capture the diversity of users' preferences and leave some items or users be badly modeled. We propose a Hybrid aspect-based latent factor model(HALFM),which jointly optimizes the Global aspect-based latent factor model(GALFM) and the Local Aspect-based Latent Factor Models(LALFM), their user-specific combination,and the assignment of users to the LALFMs. HALFM makes prediction by combining user-specific of GALFM and many LALFMs. Experimental results demonstrate that the proposed HALFM outperforms most of aspectbased recommendation techniques in rating prediction.

关键词： Recommender systems Latent factor model Review aspect

Penetration Estimation of GMA Backing Welding Based on Weld Pool Geometry Parameters

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Chinese Journal of Mechanical Engineering 2019年第3期32卷 134-144页

作者： Junfen Huang Long Xue Jiqiang Huang Yong Zou Ke Ma Opto-Mechatronic Equipment technology beijing Area Major Laboratory Beijing Institute of Petrochemical Technology

Penetration estimation is a prerequisite of the automation of backing welding based on vision sensing technology. However, the arc interference in welding process leads to the difficulties of extracting the weld pool characteristic information, which brings great challenges to the penetration estimation. At present, most researches focus on the extraction of weld pool geometry parameters, and the visual sensing systems are complex in structure and complicated in the image processing algorithms. The research of penetration estimation based on weld pool geometry parameters is still in the exploratory stage. The purpose of this paper is to research the relationship between the weld pool geometry parameters and the penetration during backing welding and to estimate penetration using the weld pool geometry parameters. A passive vision sensing test system for gas metal arc (GMA) backing welding was established. An image processing algorithm was developed to extract the weld pool geometry parameters, namely, the area, maximum width and length, half-length, length-width ratio and advancing contact angle (simplified as AWP, MWWP, MLWP, HLWP, LWR and ACA, respectively). The corresponding relationships between the weld pool geometry parameters and the penetration state were explored by analysing their changes with the welding current and speed. The distribution of the weld pool geometry parameters corresponding to penetration was determined. When the AWP of the weld pool is within a certain range and the values of LWR and ACA are close to their maximum and minimum respectively, the penetration is in good condition. A mathematical model with the weld pool geometry parameters as independent variables and the back-bead width (the indicator of the penetration state) as a dependent variable was established based on multivariable linear regression analysis, and relevant statistical tests were carried out. Multivariable linear regression equations for the weld pool geometry parameter

关键词： Welding automation Passive vision sensing Weld pool geometry parameters Penetration state Mathematical model