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Comprehensive Evaluation Method for Traffic Flow Data Quality based on Grey Correlation Analysis and Particle Swarm Optimization

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 106-128页

作者： Wei ba baojun Chen Qi Li School of Automation and Electrical Engineering Dalian Jiaotong UniversityDalian116028China Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian116023China

Nowadays,data are more and more used for intelligent modeling and prediction,and the comprehensive evaluation of data quality is getting more and more attention as a necessary means to measure whether the data are usable or ***,the comprehensive evaluation method of data quality mostly contains the subjective factors of the evaluator,so how to comprehensively and objectively evaluate the data has become a bottleneck that needs to be solved in the research of comprehensive evaluation *** order to evaluate the data more comprehensively,objectively and differentially,a novel comprehensive evaluation method based on particle swarm optimization(PSO)and grey correlation analysis(GCA)is presented in this *** first,an improved GCA evaluation model based on the technique for order preference by similarity to an ideal solution(TOPSIS)is ***,an objective function model of maximum difference of the comprehensive evaluation values is built,and the PSO algorithm is used to optimize the weights of the improved GCA evaluation model based on the objective function ***,the performance of the proposed method is investigated through parameter analysis.A performance comparison of traffic flow data is carried out,and the simulation results show that the maximum average difference between the evaluation results and its mean value(MDR)of the proposed comprehensive evaluation method is 33.24%higher than that of TOPSIS-GCA,and 6.86%higher than that of *** proposed method has better differentiation than other methods,which means that it objectively and comprehensively evaluates the data from both the relevance and differentiation of the data,and the results more effectively reflect the differences in data quality,which will provide more effective data support for intelligent modeling,prediction and other applications.

关键词： Data quality comprehensive evaluation particle swarm optimization grey correlation analysis traffic flow data

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Boosting CO_(2) hydrogenation to high-value olefins with highly stable performance over ba and na co-modified Fe catalyst

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Journal of Energy Chemistry 2023年第5期80卷 614-624,I0014页

作者： Joshua Iseoluwa Orege na Liu Cederick Cyril Amoo Jian Wei Qingjie Ge Jian Sun Dalian national Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

CO_(2)hydrogenation has been considered to be a highly promising route for the production of high-value olefins(HVOs)while also mitigating CO_(2)***,it is challenging to achieve high selectivity and maintain stable performance for HVOs(ethylene,propylene,and linear a-olefins)over a prolonged reaction time due to the difficulty in precise control of carbon coupling and rapid catalyst ***,we present a selective ba and na co-modified Fe catalyst enriched with Fe_(5)C_(2)and Fe_(3)C active sites that can boost HVO synthesis with up to 66.1%selectivity at an average CO_(2)conversion of 38%for over 500 *** to traditional naFe catalyst,the combined effect of ba and na additives in the nabaFe-0.5 catalyst suppressed excess oxidation of FeCxsites by H_(2)*** absence of Fe3O4phase in the spent nabaFe-0.5 catalyst reflects the stabilization effect of the co-modifiers on the *** study provides a strategy to design Fe-based catalysts that can be scaled up for the stable synthesis of HVOs from CO_(2)hydrogenation.

关键词： CO_(2)hydrogenation High-value olefins barium additive Iron carbide Catalytic stability

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Diffraction of SH-waves by topographic features in a layered transversely isotropic half-space

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 11-22页

作者： ba Zhenning Liang Jianwen Zhang Yanju Department of Civil Engineering Tianjin University Tianjin 300072 China Key Laboratory of Coast Civil Structure Safety ( Tianjin University) Ministry of Education Tianjin 300072 China

Abstract： The scattering of plane SH-waves by topographic features in a layered transversely isotropic （TI） half-space is investigated by using an indirect boundary element method （IBEM）. Firstly, the anti-plane dynamic stiffness matrix of the layered TI half-space is established and the free fields are solved by using the direct stiffness method. Then, Green＇s functions are derived for uniformly distributed loads acting on an inclined line in a layered TI half-space and the scattered fields are constructed with the deduced Green＇s functions. Finally, the free fields are added to the scattered ones to obtain the global dynamic responses. The method is verified by comparing results with the published isotropic ones. Both the steady-state and transient dynamic responses are evaluated and discussed. Numerical results in the frequency domain show that surface motions for the TI media can be significantly different from those for the isotropic case, which are strongly dependent on the anisotropy property, incident angle and incident frequency. Results in the time domain show that the material anisotropy has important effects on the maximum duration and maximum amplitudes of the time histories.

关键词： wave scattering and diffraction Green's function transversely isotropic SH-waves indirect boundaryelement method

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P-wave velocity prediction in porous medium with liquid-pocket patchy saturation

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Applied Mathematics and Mechanics(English Edition) 2015年第11期36卷 1427-1440页

作者： Jiawei LIU Weitao SUN Jing ba Zhou Pei-Yuan Center for Applied Mathematics Tsinghua University Department of Computational Geophysics Xi'an Jiaotong University

It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical gas pockets were located at the center of a liquid saturated cube. For an extremely light and compressible inner gas, the physical properties can be approximated by a vacuum with White＇s model. The model successfully analyzes the dispersion phenomena of a P-wave velocity in gas-water- saturated rocks. In the case of liquid pocket saturation, e.g., an oil-pocket surrounded by a water saturated host matrix, the light fluid-pocket assumption is doubtful, and few works have been reported in White＇s framework. In this work, Poisson＇s ratio, the bulk modulus, and the effective density of a dual-liquid saturated medium are formulated for the heterogeneous porous rocks containing liquid-pockets. The analysis of the difference between the newly derived bulk modulus and that of White＇s model shows that the effects of liquid-pocket saturation do not disappear unless the porosity approaches zero. The inner pocket fluid can no longer be ignored. The improvements of the P-wave velocity predictions are illustrated with two examples taken from experiments, i.e., the P-wave velocity in the sandstone saturated by oil and brine and the P-wave velocity for heavy oils and stones at different temperatures.

关键词： White's model porous medium P-wave dispersion liquid pocket

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In-plane dynamic Green's functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic half-space

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Earthquake Engineering and Engineering Vibration 2018年第2期17卷 293-309页

作者： ba Zhenning Kang Zeqing Liang Jianwen Department of Civil Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Coast Civil Structure Safety(Tianjin University) Tianjin 300072China

The dynamic stiffness method combined with the Fourier transform is utilized to derive the in-plane Green’s functions for inclined and uniformly distributed loads in a multi-layered transversely isotropic（TI）*** loaded layer is fixed to obtain solutions restricted in it and the corresponding reactions forces,which are then applied to the total system with the opposite *** adding solutions restricted in the loaded layer to solutions from the reaction forces,the global solutions in the wavenumber domain are obtained,and the dynamic Green’s functions in the space domain are recovered by the inverse Fourier *** presented formulations can be reduced to the isotropic case developed by Wolf（1985）,and are further verified by comparisons with existing solutions in a uniform isotropic as well as a layered TI halfspace subjected to horizontally distributed loads which are special cases of the more general problem *** deduced Green’s functions,in conjunction with boundary element methods,will lead to significant advances in the investigation of a variety of wave scattering,wave radiation and soil-structure interaction problems in a layered TI *** numerical results are given to investigate the influence of material anisotropy,frequency of excitation,inclination angle and layered on the responses of displacement and stress,and some conclusions are drawn.

关键词： Green's functions transversely isotropic medium multi-layered half-space stiffness method dynamic response

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Effect of mineral admixtures and repeated loading on chloride migration through concrete

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第9期11卷 683-690页

作者： Wu-man ZHANG Heng-jing ba School of Transportation Science and Engineering Beihang University Beijing 100191 China School of Civil Engineering Harbin Institute of Technology Harbin 150006 China

The effect of fly ash (FA) and ground granulated blast furnace slag (GGBFS) on chloride migration through concrete subjected to repeated loading was examined. Portland cement was replaced by three percentages (20%, 30%, and 40%) of mineral admixtures. Five repeated loadings were applied to concrete specimens using a WHY series fully automatic testing machine. The maximum loadings were 40% and 80% of the axial cylinder compressive strength (f′c). Chloride migration through concretes was evaluated using the rapid chloride migration test and the chloride concentration in the anode chamber was measured. The results showed that the replacement percentages of mineral admixtures, the curing time and repeated loading had a significant effect on chloride migration through concrete. The transport number of chloride through concrete cured for 28 d increased with increasing FA replacement and markedly decreased with extension of the curing time. 20% and 30% GGBFS replacement decreased the transport number of chloride through concrete, but 40% GGBFS replacement increased the transport number. Five repeated loadings at 40% or 80% f′c increased the transport number of chloride for all mixes.

关键词： Concrete Fly ash (FA) Ground granulated blast furnace slag (GGBFS) Chloride migration Repeated loading

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Water-stable ZIF-300/Ultrason? mixed-matrix membranes for selective CO_2 capture from humid post combustion flue gas

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1012-1021页

作者： Muhammad Sarfraz M. ba-Shammakh Department of Polymer and Process Engineering University of Engineering and Technology Lahore 54890 Pakistan Department of Chemical Engineering King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

Water stable mixed-matrix membranes(MMMs) were developed to help control the global warming by capturing and sequestrating carbon dioxide(CO_2) from post-combustion flue gas originated from burning of fossil *** of different compositions were prepared by doping glassy polymer Ultrason? S 6010(US) with nanocrystals of zeolitic imidazolate frameworks(ZIF-300) in varying degrees. Solution-casting technique was used to fabricate various MMMs to optimize their CO_2 capturing performance from both dry and wet gases. The prepared composite membranes indicated enhanced filler-polymer interfacial adhesion, consistent distribution of nanofiller, and thermally established matrix configuration. CO_2 permeability of the membranes was enhanced as demonstrated by gas sorption and permeation experiments performed under both dry and wet conditions. As compared to neat Ultrason? membrane, CO_2 permeability of the composite membrane doped with 40 wt% ZIF-300 nanocrystals was increased by four times without disturbing CO_2/N_2 ideal selectivity. In contrast to majority of previously reported membranes, key features of the fabricated MMMs include their structural stability under humid conditions coupled with better and unaffected gas separation performance.

关键词： Hydrophobic MMMs ZIF-300 Gas permeation CO2 capture Permselectivity

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Scattering and diffraction of plane SH-waves by periodically distributed canyons

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 325-339页

作者： ba Zhenning Liang Jianwen Zhang Yanju Department of Civil Engineering Tianjin University Key Laboratory of Coast Civil Structure Safety (Tianjin University) Ministry of Education

A new method is presented to study the scattering and diffraction of plane SH-waves by periodically distributed canyons in a layered half-space. This method uses the indirect boundary element method combined with Green＇s functions of uniformly distributed loads acting on periodically distributed inclined lines. The periodicity feature of the canyons is exploited to limit the discretization effort to a single canyon, which avoids errors induced by the truncation of the infinite boundary, and the computational complexity and the demand on memory can be significantly reduced. Furthermore, the total wave fields are decomposed into the free field and scattered field in the process of calculation, which means that the method has definite physical meaning. The implementation of the method is described in detail and its accuracy is verified. Parametric studies are performed in the frequency domain by taking periodically distributed canyons of semi-circular and semi-elliptic cross-sections as examples. Numerical results show that the dynamic responses of periodically distributed canyons can be quite different from those for a single canyon and significant dynamic interactions exist between the canyons.

关键词： periodically layered uniformly verified decomposed truncation elliptic discretization scattered circular

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Effects of Cr2O3 doping on the microstructure and electrical properties of （ba,Ca）（Zr,Ti）O3 lead-free ceramics

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Frontiers of Materials Science 2016年第2期10卷 203-210页

作者： Xiang XlA Xiangping JIANG Chao CHEN Xingan JIANG na TU Yunjing CHEN Jiangxi Key Laboratory of Advanced Ceramic Materials School of Materials Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China

Lead-free ceramics （ba0.85Ca0.15）（Zr0.1Ti0.9）O3-x wt,%Cr2O3 （BCZT-xCr） were prepared via the conventional solid-state reaction method. The microstructure and electrical properties of BCZT-xCr samples were systematically studied. XRD and Raman results showed that all samples possessed a single phased perovskite structure and were close to the morphotropic phase boundary （MPB）. With the increase of the Cr content, the rhombohedral-tetragonal phase transition temperature （TR-T） increases slightly, and the Curie temperature （Tc） shifts towards the low temperature side. XPS analysis reveals that Cr3. and Cr5＊ ions co-existed in Cr-doped BCZT ceramics, indicating the different impact on the electrical properties from Cr ions as ＂acceptor＂ or ＂donor＂. For the x = 0.1 sample, relative high piezoelectric constants d33 （-316 pC/N） as well as high Qm （-554） and low tan6 （-0.8%） were obtained. In addition, the AC conductivity was also investigated. Hopping charge was considered as the main conduction mechanism at low temperature. As the temperature increases, small polarons and oxygen vacancies conduction played important roles.

关键词： lead-free ceramics electrical properties BCZT XPS analysis

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Treatment strategies for patients with HER2-positive gastric cancer

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Cancer Biology & Medicine 2023年第12期20卷 934-941页

作者： Feixue Wang Yi ba Department of Medical Oncology Department of Cancer CenterPeking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100032China Department of GI Medical Oncology Tianjin Medical University Cancer Institute&HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerTianjin Key Laboratory of Digestive CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060China

Gastric cancer (GC) is a major health concern globally,ranking fifth in frequency and fourth in cancer-associated *** China,an estimated 396,500 new cases are diagnosed each year,and late-stage disease comprises more than 80%of *** of late diagnosis and heterogeneous characteristics,the prognosis of GC remains *** patients with advanced disease,traditional chemotherapy has been the mainstay of treatment,but its clinical outcomes are far from satisfactory,with a 5-year survival rate below 10%.

关键词： patients cancer Gastric

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