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Phase precipitation and isothermal crystallization kinetics of FeZrB amorphous alloy

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Advances in Manufacturing 2013年第3期1卷 251-257页

作者： Bing-Ge zhao Ling-Hong Kong ting-ting Song Qi-Jie Zhai yu-Lai Gao Laboratory for Microstructures Shanghai University School of Materials Science and Engineering Shanghai University

The crystallization process of Fe78ZrTBls （at%） amorphous ribbon was investigated by Xray diffraction （XRD）, differential scanning calorimetry and scanning electron microscopy （SEM）. The fully amorphous structure of asquenched （Aq） ribbons was confirmed by XRD pattern. The saturation magnetization （Ms） and Curie tem perature of the Aq ribbon were measured as 124.3 （***）＆g and 305 ℃ with vibrating sample magnetometer （VSM）, respectively. When the ribbons was annealed at 550 ℃ near the first onset temperature （Txl = 564.9 ℃）, the Ms was increased by 17 %, which was caused by the formation of a dual phase structure. The isothermal crystallization kinetics and crystallization mechanism of primary ctFe phase in the dual phase structure were studied by Arrhenius and JohnsonMehlAvramiKolmogorov equations respectively. The results showed that the crystallization of Fe phase was a diffusioncontrolled surface nucleation growth process, and the nucleation rate decreased with longer crystallization time.

关键词： Crystallization Dual phase structure Activation energy Avrami exponent

Iterative parameter estimate with batched binary-valued observations

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Science China(Information Sciences) 2016年第5期59卷 158-175页

作者： Yanlong zhao Wenjian BI ting WANG Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, we consider linear system identification with batched binary-valued *** constructed an iterative parameter estimate algorithm to achieve the maximum likelihood(ML) *** first interesting result was that there exists at most one finite ML solution for this specific maximum likelihood problem, which was induced by the fact that the Hessian matrix of the log-likelihood function was negative definite under binary data and Gaussian system noises. The global concave property and local strongly concave property of the log-likelihood function were obtained. Under mild conditions on the system input, we proved that the ML function has a unique maximum point. The second main result was that the ML estimate was consistent under persistent excitation inputs, which infers the effectiveness of ML estimate. Finally, the proposed iterative estimate algorithm converged to a fixed vector with an exponential rate that was proved by constructing a Lyapunov function. A more interesting result was that the limit of the iterative algorithm achieved the maximization of the ML function. Numerical simulations are illustrated to support the theoretical results obtained in this paper well.

关键词： Binary-valued observation maximum likelihood estimate strongly convex system identification exponential rate

Consensus Control With a Constant Gain for Discrete-time Binary-valued Multi-agent Systems Based on a Projected Empirical Measure Method

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IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 1052-1059页

作者： ting Wang Min Hu Yanlong zhao IEEE the Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China the School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China

This paper studies the consensus control of multiagent systems with binary-valued *** algorithm alternating estimation and control is *** agent estimates the states of its neighbors based on a projected empirical measure method for a holding *** on the estimates,each agent designs the consensus control with a constant gain at some skipping *** states of the system are updated by the designed control,and the estimation and control design will be *** the estimation,the projected empirical measure method is proposed for the binary-valued *** algorithm can ensure the uniform boundedness of the estimates and the mean square error of the estimation is proved to be at the order of the reciprocal of the holding time(the same order as that in the case of accurate outputs).For the consensus control,a constant gain is designed instead of the stochastic approximation based gain in the existing literature for binary-valued ***,there is no need to make modification for control since the uniform boundedness of the estimates ensures the uniform boundedness of the agents’***,the systems updated by the designed control are proved to achieve consensus and the consensus speed is faster than that in the existing *** are given to demonstrate the theoretical results.

关键词： Binary-valued observations consensus control constant gain convergence rate multi-agent systems projected empirical measure method

Groundwater impact of open cut coal mine and an assessment methodology:A case study in NSW

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International Journal of Mining Science and Technology 2017年第5期27卷 861-866页

作者： zhao Liang ting Ren Wang Ningbo Shenhua Watermark Coal Ltd Pty GunnedahNSW 2380Australia School of Civil Mining and Environmental EngineeringUniversity of WollongongNSW 2522Australia School of Mines China University of Mining&TechnologyXuzhou 221116China

Large scale open cut coal mining operations have significant impacts to groundwater in surrounding areas in both active and post-mining phases. The prediction of water inflows into a surface mine excavation is one of the many components involved in mine design phase. Groundwater performance also reacts to mining activities from the operational, economic and safety implications perspective. Under NSW planning legislation, as part of the comprehensive risk assessment, a groundwater impact assessment has to be conducted for a coal project to predict and mitigate the impacts in consideration of the government requirements. In this paper, the groundwater assessment modelling of mine pits was discussed in predicting of groundwater inflows and reviewing analytical and numerical approaches. A methodology of groundwater impact assessment for an open cut mine in NSW with a three-dimensional groundwater flow model Modflow Surfact demonstrated its functions in simulating the project's impacts on the groundwater regime. The key findings with mitigations are discussed and recommended in the paper to reduce impacts on groundwater and fulfil regulation requirements in NSW.

关键词： Open cut coal mine Groundwater impact assessment Mining exposure area Groundwater modelling methodology

Transmissive-detected laser speckle contrast imaging for blood flow monitoring in thick tissue: from Monte Carlo simulation to experimental demonstration

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Light(Science & Applications) 2021年第12期10卷 2492-2506页

作者： Dong-yu Li Qing Xia ting-ting yu Jing-Tan Zhu Dan Zhu Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology430074 WuhanHubeiChina MoE Key Laboratory for Biomedical Photonics Huazhong University of Science and Technology430074 WuhanHubeiChina

Laser speckle contrast imaging(LSCI)is a powerful tool to monitor blood flow distribution and has been widely used in studies of microcirculation,both for animal and clinical ***,LSCI usually works on reflectivedetected ***,it could provide promising temporal and spatial resolution for in vivo applications only with the assistance of various tissue windows,otherwise,the overlarge superficial static speckle would extremely limit its contrast and ***,we systematically investigated the capability of transmissive-detected LSCI(TR-LSCI)for blood flow monitoring in thick *** Monte Carlo simulation,we theoretically compared the performance of transmissive and reflective *** was found that the reflective-detected mode was better when the target layer was at the very surface,but the imaging quality would rapidly decrease with imaging depth,while the transmissivedetected mode could obtain a much stronger signal-to-background ratio(SBR)for thick *** further proved by tissue phantom,animal,and human experiments that in a certain thickness of tissue,TR-LSCI showed remarkably better performance for thick-tissue imaging,and the imaging quality would be further improved if the use of longer wavelengths of near-infrared ***,both theoretical and experimental results demonstrate that TR-LSCI is capable of obtaining thick-tissue blood flow information and holds great potential in the field of microcirculation research.

关键词： reflective thick speckle

FIR system identification with set-valued and precise observations from multiple sensors

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Science China(Information Sciences) 2019年第5期62卷 179-194页

作者： Hang ZHANG ting WANG Yanlong zhao Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper considers the system identification problem for FIR(finite impulse response) systems with set-valued and precise observations received from multiple sensors. A fusion estimation algorithm based on some suitable identification algorithms for different types of observations is proposed. In particular, least square method is chosen for FIR systems with precise observations, while empirical measure method and EM algorithm are chosen for FIR systems with set-valued observations in the cases of periodic and general system inputs, respectively. Then, the quasi-convex combination estimator(QCCE) fusing the two different estimators by a linear combination with appropriate weights is constructed. Furthermore, the convergence properties are theoretically analyzed in terms of strong consistency and asymptotic efficiency. The fused estimator QCCE is proved to achieve the Cram′er-Rao(CR) lower bound asymptotically under periodic inputs. Extensive numerical simulations validate the superiority of the fusion estimation algorithm under both periodic and general inputs.

关键词： system identification FIR system set-valued precise fusion estimation quasi-convex combination estimator

One-step synthesis of Cu(Ⅱ) metal–organic gel as recyclable material for rapid, efficient and size selective cationic dyes adsorption

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Journal of Environmental Sciences 2019年第12期31卷 203-212页

作者： Qing Wu Li He Zhong Wei Jiang Yang Li ting ting zhao yu Han Li Cheng Zhi Huang yuan Fang Li Key Laboratory of Luminescent and Real-Time Analytical Chemistry(Southwest University) Ministry of EducationSchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China College of Pharmaceutical Science Soiithiuest UniuersityChongqing 400715China College of Science Beihua UniversityJilin 132013China

Efficient removal of non-biodegradable and hazardous dyes from wastewater remains a hot research ***,a rationally designed a Cu(Ⅱ)-based metal–organic gel(Cu-MOG)with a nanoporous 3 D network structure prepared via a simple one-step mixing method was successfully employed for the removal of cationic *** Cu-MOG exhibited high efficiency,with an adsorption capacity of up to 650.32 mg/g,and rapid adsorption efficiency,with the ability to adsorb 80%of Neutral Red within 1 *** high adsorption efficiency was attributed to its large specific surface area,which enabled it to massively bind cationic dyes through electrostatic interaction,and a nanoporous structure that promoted intra-pore ***,the Cu-MOG displayed size-selective adsorption,based on adsorption studies concerning dyes of different sizes as calculated by density functional ***,the adsorption performance of the Cu-MOG still maintained removal efficiency of 100%after three regeneration *** results suggested that the Cu-MOG could be expected to be a promising and competitive candidate to conveniently process wastewater.

关键词： Cu(Ⅱ)-based metal–organic gel Electrostatic interaction Intraporous diffusion Dyes removal Size selective

Encoding syntactic representations with a neural network for sentiment collocation extraction

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Science China(Information Sciences) 2017年第11期60卷 7-18页

作者： Yanyan zhao Bing QIN ting LIU Department of Media Technology and Art Harbin Institute of Technology Department of Computer Science and Technology Harbin Institute of Technology

Sentiment collocation refers to the collocation of a target word and a polarity word. Sentiment collocation extraction aims to extract the targets and their modifying polarity words by analyzing the relationships between them. This can be regarded as a basic sentiment analysis task and is relevant in many practical applications. Previous studies relied mainly on the syntactic path, which is used to connect the target word and the polarity word. To deeply exploit the semantic information of the syntactic path, we propose two types of syntactic representation, namely, relation embedding and subtree embedding, to capture the latent semantic features. Relation embedding is used to represent the latent semantics between targets and their corresponding polarity words, and subtree embedding is used to explore the rich syntactic information for each word on the path. To combine the two types of syntactic representations, a neural network is constructed. We use a recursive neural network(RNN) to model the subtree embeddings, and then the subtree embedding and the word embedding are combined as the enhanced word representation for each word in the syntactic path. Finally,a convolutional neural network(CNN) is adopted to integrate the two types of syntactic representations to extract the sentiment collocations from reviews. Our experiments were conducted on six types of reviews, which included product domains(such as cameras and phones) and service domains(such as hotels and restaurants).The experimental results show that our proposed method can accurately capture the latent semantic features hidden behind the syntactic paths that neither the common feature-based methods nor the syntactic-path-based method can handle, and, further, that it significantly outperforms numerous baselines and previous methods.

关键词： sentiment collocation extraction sentiment analysis syntactic representation neural network re cursive neural network(RNN) convolutional neural network(CNN)

Heterogeneity Analysis of Cucumber Canopy in the Solar Greenhouse

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Journal of Integrative Agriculture 2014年第12期13卷 2645-2655页

作者： QIAN ting-ting LU Sheng-lian zhao Chun-jiang GUO Xin-yu WEN Wei-liang DU jian-jun Shanghai Jiao Tong University Beijing Research Center for Information Technology in Agriculture

Detailed analysis of canopy structural heterogeneity is an essential step in conducting parameters for a canopy structural model. This paper aims to analyze the structural heterogeneity of a cucumber （Cucumis sativus L.） canopy by means of analyzing leaf distribution in a greenhouse environment with natural sunlight and also to assess the effect of structural canopy heterogeneity on light interception and photosynthesis. Two experiments and four measurements were carried out in autumn 2011 and spring 2012. A static virtual three-dimensional （3D） canopy structure was reconstructed using a 3D digitizing method. The diurnal variation of photosynthesis rate was measured using CIRAS-2 photosynthesis system. The results showed that, leaf azimuth as tested with the Rayleigh-test was homogeneous at vine tip over stage but turned heterogeneous at fruit harvest stage. After eliminating the inlfuence of the environment on the azimuth using the von Mises-Fisher method, the angle between two successive leaves was 144°;at the same time, a rule for the azimuth distribution in the canopy was established, stating that the azimuth distribution in cucumber followed a law which was positive spin and anti-spin. Leaf elevation angle of south-oriented leaves was on average 13.8° higher than that of north-oriented leaves. The horizontal distribution of light interception and photosynthesis differed signiifcantly between differently oriented leaves. East-and west-oriented leaves exhibited the highest photosynthetic rate. In conclusion, detailed analysis of canopy structural heterogeneity in this study indicated that leaf azimuth and elevation angle were heterogeneous in cucumber canopy and they should be explicitly described as they have a great impact both on light distribution and photosynthesis.

关键词： heterogeneity inclination leaf azimuth light interception photosynthesis