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Journal of Mountain Science 2011年第2期8卷 239-245页

作者： MUKOYAMA Sakae Department of research & Development of Kokusai Kogyo Co. Ltd.

In this study, a new method for quantitative and efficient measurement for the ground surface movement was developed. The feature of this technique is to identify geomorphic characteristics by image matching analysis, using the intelligent images made from high resolution DEM(Digital Elevation Model). This method is useful to extract the small ground displacement where the surface shape was not intensely deformed.

关键词： Ground deformation Ground surface movement Digital Elevation Model(DEM) Geomorphic image analysis Japan

Evaluation of strategies for the ultra-rapid orbit prediction of BDS GEO satellites

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Geo-Spatial Information Science 2023年第1期26卷 16-30页

作者： Wenxi Zhao Xiaolei Dai Yidong Lou Yaquan Peng Xueyong Xu GNSS research Center Wuhan UniversityWuhanChina Northern Information Control research Academy Group Co.ltd. NanjingChina

The quality of BeiDou Navigation Satellite System(BDS)Geostationary Earth Orbit(GEO)ultrarapid products is unsatisfactory because GEO satellites are nearly stationary relative to ground *** optimize the quality of these ultra-rapid orbit products,we investigated the effects of the fitting arc length,an a priori Solar-Radiation Pressure(SRP)model,and the along-track empirical acceleration on the prediction of BDS GEO satellite *** predicted orbit arcs of 24-h were evaluated through comparisons with the corresponding observed orbit arc and Satellite Laser Ranging(SLR)*** both eclipse and non-eclipse seasons,accuracy of the orbit predictions obtained using a 48-h fitting arc length were better than those obtained using 24-h and 72-h fitting arc *** the overlapping precision of predicted orbits exhibited no obvious improvement when an a priori SRP model was employed,the systematic bias in the SLR residuals was significantly ***,the mean value of SLR residuals decreased from−0.248 m to−0.024 m during non-eclipse seasons and from−0.333 m to−0.041 m during eclipse seasons,*** addition,when an empirical acceleration in the along-track direction was introduced,the three-Dimensional Root-Mean-Square(3D RMS)of overlapping orbits during eclipse seasons decreased from 2.964 to 1.080 m,which is comparable to that during non-eclipse ***,the Standard Deviation(STD)of SLR residuals decreased from 0.419 to 0.221 m during eclipse *** analysis of SRP estimates shows that the stability of SRP parameters was significantly enhanced after the introduction of along-track empirical acceleration in eclipse *** optimal BDS GEO ultra-rapid orbit prediction products were yielded by using a 48-h fitting arc length,an a priori SRP model and an along-track empirical acceleration.

关键词： BDS GEO satellites orbit prediction solar radiation pressure model

Performance evaluation for selectivity of the flocculant on hematite in selective flocculation

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1123-1129页

作者： Lopamudra Panda Pradip K.Banerjee Surendra Kumar Biswal R.Venugopal N.R.Mandre research and Development Tata Steel Ltd. Institute of Minerals and Materials Technology (Council of Scientific and Industrial research) Indian School of Mines University

Increased demand for iron ore necessitates the utilization of low-grade iron ore fines, slimes, and existing tailings. Selective flocculation can be an alternative physico-chemical process for utilizing these low-grade fines, slimes, and tailings. In selective fiocculation, the most critical objective is the selection of proper reagents that will make fioc of desired minerals. In present study, selective flocculation was applied to ultra-fine synthetic mixtures of hematite and kaolinite, and the Fe value was upgraded up to 65.78% with the reduction of Al2O3 and SiO2 values to 2.65% and 3.6670, respectively. Here, degraded wheat starch was used as a *** this process, separation occurs on the basis of the selectivity of the flocculant. The selectivity of the fiocculant can be quantified in terms of separation efficiency. Here, an attempt was also made to develop a correlation between separation efficiency and major operating parameters such as flocculent dose, pH value, and solid concentration to predict the separation performance.

关键词： hematite kaolinite selective fiocculation modeling iron ores tailings

Effect of grain size on thermal stability and oxygen storage capacity of Ce_(0.17)Zr_(0.73)La_(0.02)Nd_(0.04)Y_(0.04)O_2 solid solutions

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Journal of Rare Earths 2019年第2期37卷 178-184页

作者： Yuhui Zhang Meisheng Cui Yongke Hou Xiaowei Huang Yongqi Zhang Qiannan Xue National Engineering research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co.ltd.

Nanostructured CeO_2-ZrO_2 materials are an irreplaceable constituent in catalytic systems for automobile exhaust purification due to their unique oxygen storage capacity(OSC). However, traditional CeO_2-ZrO_2 materials are easy to sinter at high temperature, which causes a sharp decrease of OSC. In this paper,La^(3+) , Nd^(3+) and Y^(3+) are chosen as dopants for CeO_2-ZrO_2 to improve anti-sintering and OSC *** Ce_(0.17) Zr_(0.73) La_(0.02) Nd_(0.04) Y_(0.04) O_2 powders(CZLNY) were prepared by co-precipitation method. The effects of grain sizes with different mixed chlorinated solution concentrations on performances were investigated. X-ray diffraction(XRD) and transmission electron micrograph(TEM) were performed to calculate the grain sizes of CZLNY. The specific surfaces, OSC and redox properties were investigated by N_2 adsorption/desorption and temperature programmed reduction(H2-TPR). The results show that introducing La^(3+) , Nd^(3+) and Y^(3+) into CeO_2-ZrO_2 lattice can improve the stability of phase structure and anti-sintering ability. Moreover, low concentration of mixed chlorinated solution remarkably improves structural and textural properties of CZLNY. Relatively large fresh grain exhibits superior thermal stability and OSC under the condition of being calcined at 800℃ for 3 h. The specific surface and OSC are42.37 m^2/g and 333.13 mmol/g after calcining at 1000℃ for 10 h, respectively. This is owing to the low sintered driving force of large grain and long-range migration energy of large pores during the sintering process, which are beneficial to the stability of structure in CZLNY materials.

关键词： Grain size Thermal stability Oxygen storage capacity CeO2-ZrO2 Rare earths

Fault reconstruction observer design for continuous-time systems with measurement disturbances via descriptor system approach

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Journal of Systems Engineering and Electronics 2014年第5期25卷 877-885页

作者： Qingxian Jia Yingchun Zhang Chengliang Li Xueqin Chen research Center of Satellite Technology Harbin Institute of Technology Aerospace Dongfanghong Development ltd

This paper addresses a problem of observer-based sensor fault reconstruction for continuous-time systems subject to sensor faults and measurement disturbances via a descriptor system approach. An augmented descriptor plant is first formulated, by assembling measurement disturbances and sensor faults into an auxiliary state vector. Then a novel descriptor state observer for the augmented plant is constructed such that simultaneous reconstruction of original system states, sensor faults and measurement disturbances are obtained readily. Sufficient conditions for the existence of the proposed observer are explicitly provided, and the application scope of the observer is further discussed. In addition, an extension of the proposed linear approach to a class of nonlinear systems with Lipschitz constraints is investigated. Finally, two numerical examples are simulated to illustrate the effectiveness of the proposed fault-reconstructing approaches.

关键词： fault reconstruction descriptor system approach ob- server design measurement disturbance.

Friction moment analysis of space gyroscope bearing with ribbon cage under ultra-low oscillatory motion

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Chinese Journal of Aeronautics 2014年第5期27卷 1301-1311页

作者： Jiang Shaona Chen Xiaoyang Gu Jiaming Shen Xuejin research Institute of Bearings Shanghai University Shanghai Tianan Bearing Co. Ltd

This paper presents the model of calculating the total friction moment of space gyroscope ball bearings which usually work under ultra-low oscillatory motion and are very sensitive to the friction moment. The aim is to know the proportion of the friction moment caused by each frictional source in the bearing＇s total friction moment, which is helpful to optimize the bearing design to deduce the friction moment. In the model, the cage dynamic equations considering six degree-of-freedom and the balls dynamic equations considering two degree-of-freedom were *** good trends with different loads between the measured friction moments and computational results prove that the model under constant rate was validated. The computational results show that when the speed was set at 5 r/min, the bearing＇s maximum total friction moment when oscillation occurred was obviously larger than that occurred at a constant rate. At the onset of each oscillatory motion, the proportion of the friction moment caused by cage in the bearing＇s total friction moment was very high, and it increased with the increasing speed. The analyses of different cage thicknesses and different clearances between cage pocket and ball show that smaller thickness and clearance were preferred.

关键词： Ball bearings Cage thicknesses Clearances Dynamic equations Friction moment Frictional sources Oscillatory motion

Preparation of Spherical Tungsten Particles Assisted by Hydrothermal Method

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1457-1462页

作者： GUO Jiawang WEN Xiaoqiang WU Ying XU Jianbing ZHOU Jieying Ganzhou Nonferrous Metallurgy research Institute Co. LtdGanzhou 341000China

We presented a strategy to prepare spherical tungsten powder by the combination of hydrothermal method and H2reduction *** hydrothermal process,the micelle of tetraethylammonium bromide(TEAB)act as spherical templates for the deposition of tungsten oxide,whereas the excessive TEAB inhibit the formation of spherical tungsten oxide due to the dense molecular layer of TEAB on the tungsten oxide *** acid(CA)can control the formation rate and structure of the tungsten oxide when its concentration is more than 0.2 mol/L,because of its ability to coordinate with tungsten *** synergistic effect of TEAB and CA facilitates the formation of spherical tungsten oxide with nanorod *** being treated by H_(2)at 600 and 650℃,the tungsten oxide particles are reduced to tungsten particles,which maintain the spherical structure of tungsten oxide and have porous structure.

关键词： spherical tungsten particles spherical tungsten oxide hydrothermal method citric acid tetraethylammonium bromide

Preparation and electrocatalytic performance of novelintegrated Ni-Mo sulfide electrode materials for water splitting

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Rare Metals 2024年第12期43卷 6384-6393页

作者： Shan-Shan Li Qing-He Yu Jing Mi Lei Hao Li-Jun Jiang Shu-Xian Zhuang GRIMAT Engineering Institute Co. Ltd National Engineering research Center of Nonferrous Metals Materials and Products for New Energy China GRINM Group Co.Ltd. Carbon Neutrality research Center State Power Investment Corporation Central Research Institute

Advanced electrode materials for electrocatalysis of electrolytic decomposition are crucial materials in the field of hydrogen production from renewable *** this work,a new type of integrated hydrogen evolution electrode material was synthesized by selective acidification etching and in situ growth technology.A no vel-integrated Ni-Mo sulfide electrode material with a threedimensional network structure was successfully prepared using a two-step method（convenient surface modification and in situ growth techniques）,which involved surface modification at 30% HNO3for 10 min and followed by annealing treatment at 600℃ for 1 h with 10℃·min-1heating *** structure displayed an electrochemical active surface area（ECSA） of 30.125 mF·cm-2,calculated on 0.10-0.30 V（***） CV curves with a 5-50 mV·s-1sweep rate *** ECS A of other samples was also tested by aforementioned methods,which had great distinction on ECS A with different *** novel-integrated Ni-Mo sulfide electrode material appeared to have extremity electrochemical performance in a three-electrode configuration employing 1 M KOH solution as an electrolyte,including an excellent hydrogen evolution overpotential of 346 mV at the current density of500 mA·cm-2,superior Tafel slope with 103 mV·*** outstanding electrochemical performances of the novel-integrated Ni-Mo sulfide electrode materials were directly related to the distinctive integrated ***,it was facility to find that the successful preparation of novel-integrated Ni-Mo sulfide electrode material provided more selection opportunities for alkaline electrolysis of water and offered an innovative mentality for the preparation of other types of electrode materials.

关键词： In-situ growth technology Novel-integrated electrode materials Surface modification Water splitting

A User-Centric Approach to Activity Recognition and Guidance in Semantic Smart Home

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China Communications 2015年第S2期12卷 103-113页

作者： LI Haitao GUO Kun LU Yueming LI Yonghua South China University of Technology Guangdong Power Grid Co. ltd Key Laboratory of Trustworthy Distributed computing and Service (BUPT) Ministry of Education

Wireless smart home system is to facilitate people's lives and it trend to adopt a more intelligent way to provide services. It is very desirable in the recent SH market for the system to recognize users' behaviors and automatically response the corresponding activities to satisfy users' actual demands. However, activity models in the existing approaches are usually defined separately through knowledge-driven methods. These approaches cause that the activity models can't be matched with the services dynamically. To address the problem, we develop the semantic association model and a novel approach of activity recognition and guidance is presented. In our approach, the smart devices and users' requirements are described by semantic models. When the requirements are detected and understood, smart gateway can provide appropriate services, achieving activity assistance. The semantic association model allows all related elements in smart home connect with each other logically. The approach has been implemented and the results show that the success rate of the approach based on semantic association model is higher than 33% at average as compared to the approach based on predefined models. The proposed approach can effectively help people who are in trouble with learning or remembering in the common life.

关键词： Internet of Things smart home activity recognition activity guidance semantic model

Study of Macro-Mixing in a Microreactor

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China Petroleum Processing & Petrochemical Technology 2023年第4期25卷 117-126页

作者： Cao Huili Tang Xiaojin Bao Di Hou Shuandi SINOPEC research Institute of Petroleum Processing Co. Ltd.Beijing 100083 SINOPEC(Dalian)research Institute of Petroleum and Petrochemicals Co. Ltd.Dalian 116045

The transfer rate between fluids in a microreactor is directly influenced by the mixing within the reactor, which subsequently impacts the reaction rate. This paper investigates the flow behavior and macro-mixing performance in a microreactor. First, the flow performance of the Ehrfeld Miprowa microreactor is studied. Cold experiments are conducted to examine fundamental flow laws and verify the accuracy of the chosen computational fluid dynamics simulation ***, macro-mixing performance in the microreactor, both with and without internal components, is investigated through both experiment and simulation. A bromocresol violet–NaOH–H2SO4 system is utilized in the macro-mixing experiments, which explore the effects of flow rate and internal components on macro-mixing. The Navier–Stokes equation is adopted as the computational model for macro-mixing simulations, which also consider the mass transfer and diffusion of tracer. The simulation results are in good agreement with the experimental results. Both experimental and simulation results demonstrate that the presence of internal components in the microreactor enhance its macro-mixing performance.

关键词： microreactor flow model macro-mixing