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Discrimination for ablative control mechanism in solid-propellant rocket nozzle

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Science China(Technological Sciences) 2009年第10期52卷 2911-2917页

作者： HUANG HaiMing xu xiaoliang JIANG GuiQing Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China China Academy of Aerospace Aerodynamics Beijing 100074China

The ablation in solid-propellant rocket nozzle is a coupling process resulted by chemistry, heat and mass transfer. Based on the heat and mass transfer theory, the aero-thermo-dynamic, and thermo-chemical kinetics, the thermal-chemical ablation model is established. Simulations are completed on the heat flow field and chemical ablation in the nozzle with different concentrations, frequency factors and activation energy of H2. The calculation results show that the concentration and the activation energy of H2 can provoke the transformation of control mechanism, whereas the influence brought by the frequency factor of H2 is feeble under a high-temperature and high-pressure combustion circumstance. The discrimination for ablative control mechanism is dependent on both concentration and activation energy of H2. This study will be useful in handling ablation and thermal protection problem in the design of solid-propellant rocket.

关键词： nozzle ablation control mechanism activation energy frequency factor

Image recognition and empirical application of desert plant species based on convolutional neural network

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Journal of Arid Land 2022年第12期14卷 1440-1455页

作者： LI Jicai SUN Shiding JIANG Haoran TIAN Yingjie xu xiaoliang School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of SciencesBeijing 100190China Research Center on Fictitious Economy and Data Science Chinese Academy of SciencesBeijing 100190China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

In recent years,deep convolution neural network has exhibited excellent performance in computer vision and has a far-reaching *** plant taxonomic identification requires high expertise,which is *** nature reserves have problems such as incomplete species surveys,inaccurate taxonomic identification,and untimely updating of status *** and accurate recognition of plant images can be achieved by applying convolutional neural network technology to explore the best network *** 24 typical desert plant species that are widely distributed in the nature reserves in Xinjiang Uygur Autonomous Region of China as the research objects,this study established an image database and select the optimal network model for the image recognition of desert plant species to provide decision support for fine management in the nature reserves in Xinjiang,such as species investigation and monitoring,by using deep *** desert plant species were not included in the public dataset,the images used in this study were mainly obtained through field shooting and downloaded from the Plant Photo Bank of China(PPBC).After the sorting process and statistical analysis,a total of 2331 plant images were finally collected(2071 images from field collection and 260 images from the PPBC),including 24 plant species belonging to 14 families and 22 genera.A large number of numerical experiments were also carried out to compare a series of 37 convolutional neural network models with good performance,from different perspectives,to find the optimal network model that is most suitable for the image recognition of desert plant species in *** results revealed 24 models with a recognition Accuracy,of greater than 70.000%.Among which,Residual Network X_8GF(RegNetX_8GF)performs the best,with Accuracy,Precision,Recall,and F1(which refers to the harmonic mean of the Precision and Recall values)values of 78.33%,77.65%,69.55%,and 71.26%,*** t

关键词： desert plants image recognition deep learning convolutional neural network Residual Network X_8GF(RegNetX_8GF) Mobile Network V2(MobileNetV2) nature reserves

Natural Heritage Value of Xinjiang Tianshan and Global Comparative Analysis

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Journal of Mountain Science 2012年第2期9卷 262-273页

作者： xu xiaoliang YANG Zhaoping Adayi Saiken Shao Rui LIU Xinyu Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011XinjiangChina Graduate University of the Chinese Academy of Sciences Beijing 100049China

Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage *** paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tianshan according to the World Heritage *** biological,ecological and aesthetic values,which are of global importance, are *** is concluded that Xinjiang Tianshan meets the world heritage criteria(vii)and (ix).Xinjiang Tianshan is compared with other mountain world heritage sites,mountains in Central Asia,the Tianshan Mountains outside China,and with the protected areas of the Tianshan Mountains on the Tentative List for World Heritage Sites,so as to provide objective data for the world heritage application.

关键词： Xinjiang Tianshan Natural Heritage Heritage characteristics Heritage values Comparative analysis

Sand flux estimation during a sand-dust storm at Tazhong area of Taklimakan Desert, China

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Journal of Arid Land 2011年第3期3卷 199-205页

作者： XingHua YANG xiaoliang xu Qing HE Ali Mamtimin Bo YU ShiHao TANG Institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Desert Atmosphere and Environment Observation Experiment of Taklimakan Station Tazhong 841000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China National Satellite Meteorological Center China Meteorological Administration Beijing100081 China

In this paper, the sand transport during a sand-dust storm in the Tazhong area of the central Taklimakan Desert from 11：29 to 23：56 on July 19, 2008 was observed and measured in real time. The sand flux at Tazhong was estimated using sand transport empirical formulas. The critical friction velocity at Tazhong was 0.24 m/s and the functional relation between the wind speed and sediment discharge at the height of 2 m was established. It was also found that the calculated values by Lettau＇s sediment discharge formula were close to those of the instrument measurements. The horizontal sand flux and the vertical sand flux during this sand-dust storm at Tazhong were respectively 258.67×10-4 kg/（m·s） and 40.07×10-7 kg/（m2·s）.

关键词： friction velocity sand transport flux Taklimakan Desert

Nonlinear Fusion Using Quantized Measurements and Cubature Particle Filter

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Nonlinear Fusion Using Quantized Measurements and Cubature P...

Pt-Ni core-shell structure with Pt-skin and electronic effect on catalytic performance

第25届中国控制与决策会议

作者： Xianfeng Tang Binlei Guan Quanbo Ge xiaoliang xu Modem Educational Technology Center Zhejiang University School of Electron and Information Engineering Ningbo University of Technology Institute of System Science and Control Engineering Hangzhou Dianzi University School of Computer Science and Technology Hangzhou Dianzi University

ISBN: (纸本)9781467355322

Consider the nonlinear estimation fusion problem for dynamic stochastic process in sensor networks. Due to bandwidth or energy constraints, only quantized messages of the original information from local sensor are available. For a class of vector state-vector observation model, a quantized cubature particle filter （CPF） method is presented in this paper. Firstly, each sensor quantizes each component of the measurement verbatim and sends to fusion center （FC）. Subsequently, FC compresses the quantized messages from local sensors in best linear unbiased estimation （BLUE） fusion rule. Finally, CPF is used to obtain a state estimation. Computer simulations show effectiveness of the developed method.

关键词： Nonlinear fusion Wireless sensor network Quantization Cubature particle filter

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Chinese Journal of Chemical Engineering 2023年第11期63卷 260-267页

作者： Chong Yao Dandan Ma Jie Luo Yixin Chen Min Tian Haoxuan Xie Chunshan Lu Feng Feng xiaoliang xu Qingtao Wang Qunfeng Zhang Xiaonian Li State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

In order to improve the catalytic performance of the nitrobenzene hydrogenation rearrangement to prepare p-aminophenol,a bimetallic Pt-Ni/C(PNC)catalyst was *** advantage of the synergistic effect of Ni and Pt to enhance product selectivity and catalytic performance stability,the electrons in Ni are moved to Pt by the electron effect,which affects the catalyst’s ability to activate H_(2)as well as the amount of hydrogen ***,due to the strong Pt(5d)-Ni(3d)coupling effect,Ni can effectively maintain Pt stability in the acidic system and reduce Pt *** stability of the PNC can be found to be greatly enhanced compared to the Pt/C(PC)catalyst,and p-aminophenol selectivity is greatly enhanced,showing excellent catalytic performance.

关键词： Nitrobenzene p-Aminophenol Pt-Ni/C bimetallic catalyst Electronic effect Pt(5d)-Ni(3d)coupling

Nano Ag-enhanced photoelectric conversion efficiency in all-inorganic,hole-transporting-layer-free CsPbIBr_(2) perovskite solar cells

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Chinese Physics B 2022年第12期31卷 711-717页

作者： Youming Huang Yizhi Wu xiaoliang xu Feifei Qin Shihan Zhang Jiakai An Huijie Wang Ling Liu Tiangong University Tianjin 300387China University of Science and Technology of China Hefei 230026China Nanjing University of Posts and Telecommunications Nanjing 210003China Shanxi Normal University Shanxi 041004China

All-inorganic,hole-transporting-layer-free CsPbIBr_(2)perovskite solar cells have great potential for development,but their device performance needs to be further ***,metal nanostructures have been successfully applied in the field of solar cells to improve their *** Ag-enhanced power conversion efficiency(PCE)in one CsPbIBr_(2)perovskite solar cell utilizing localized surface plasmons of Ag nanoparticles(NPs)on the surface has been researched experimentally and by simulation in this *** localized surface plasmon resonance of Ag NPs has a near-field enhancement effect,which is expected to improve the light absorption of CsPbIBr_(2)perovskite photovoltaic *** addition,Ag NPs have a forward-scattering effect on the incident light,which can also improve the performance of CsPbIBr_(2)-based perovskite photovoltaic *** directly assembling Ag NPs(with a size of about 150 nm)on the surface of fluorine-doped tin oxide it is found when the particle surface coverage is 10%,the CsPbIBr_(2)perovskite photovoltaic device achieves a best PCE of 2.7%,which is 9.76%higher than that of the control *** changing any existing structure in the ready-made solar cell,this facile and efficient method has huge *** the best of our knowledge,this paper is the first report on nano Ag-enhanced photoelectric conversion efficiency in this kind of CsPbIBr_(2)perovskite solar cell.

关键词： Ag nanoparticles local surface plasmons perovskite solar cells based on CsPbIBr_(2)

＂Overseas Training Programme on Museum Education and Curating＂ Opens at the Museum of Modern Art in New York

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China & The World Cultural Exchange 2017年第11期83卷 30-31页

作者： Xin Yu xu xiaoliang

In the critical period of the development of Chinese museum underta -ldng, successful experiences and theoretical guidance will benefit Chinese museum undertaking and problems and thoughts encountered during the devel... 详细信息

关键词：博物馆现代艺术训练计划教育纽约海外中国

纯粹理性的法律构造——《纯粹理性批判》的法哲学意蕴

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学术月刊 2016年第7期48卷 66-78页

作者：许小亮苏州大学王健法学院副教授江苏苏州215006

批判哲学体系乃是有关"世界"的世界公民哲学,这使得《纯粹理性批判》中关于知识论的阐述具有强烈的法律特质。在康德的论说中,纯粹理性的法律特质展现为裁决法庭的隐喻、原始立法者的理性事实以及先验演绎的法律程序特质。将纯粹理性作... 详细信息

批判哲学体系乃是有关"世界"的世界公民哲学,这使得《纯粹理性批判》中关于知识论的阐述具有强烈的法律特质。在康德的论说中,纯粹理性的法律特质展现为裁决法庭的隐喻、原始立法者的理性事实以及先验演绎的法律程序特质。将纯粹理性作为裁决法庭,在心智层面克服了独断语句所可能具有的独断论与专制主义特质。从原始立法者的角度对纯粹理性进行言说,则有助于我们认识到立法者与法的创作者之间的根本差异。纯粹理性自身的先验演绎揭示出程序性乃是批判哲学体系的本质。

关键词：纯粹理性裁决法庭原始立法者先验演绎