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Astronomical data fusion tool based on PostgreSQL

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Research in Astronomy and Astrophysics 2016年第11期16卷 105-112页

作者： bo Han Yan-Xia Zhang Shou-bo zhong Yong-Heng Zhao International School of Software Wuhan University Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences

With the application of advanced astronomical technologies, equipments and methods all over the world, astronomical observations cover the range from radio, infrared, visible light, ultraviolet, X-ray and gamma-ray bands, and enter into the era of full wavelength astronomy. How to effectively integrate data from different ground- and space-based observation equipments, different observers, different bands and different observation times, requires data fusion technology. In this paper we introduce a cross-match tool that is developed in the Python language, is based on the PostgreSQL database and uses Q3C as the core index, facilitating the cross-match work of massive astronomical data. It provides four different cross- match functions, namely：（I） cross-match of the custom error range; （II） cross-match of catalog errors; （III） cross-match based on the elliptic error range; （IV） cross-match of the nearest neighbor algorithm. The resulting cross-matched set provides a good foundation for subsequent data mining and statistics based on multiwavelength data. The most advantageous aspect of this tool is a user-oriented tool applied locally by users. By means of this tool, users can easily create their own databases, manage their own data and cross- match databases according to their requirements. In addition, this tool is also able to transfer data from one database into another database. More importantly, it is easy to get started with the tool and it can be used by astronomers without writing any code.

关键词： astronomical databases: miscellaneous - catalogs - surveys

Contention-Based Nonorthogonal Massive Access with Massive MIMO

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China Communications 2020年第11期17卷 79-90页

作者： Yanna Bai Wei Chen bo Ai Zhangdui zhong State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China Beijing Engineering Research Center of High-speed Railway Broadband Mobile Communications Beijing 100044China

The sporadic communication character of massive machine-type communication systems provides natural advantages to utilize the principle of compressive sensing(CS).However,due to the high computational complexity of CS algorithms,CS-based contention-free access schemes have limited scalability and high computational complexity for massive access with user-specific *** address these problems,in this paper,we propose a new contention-based scheme for CSbased massive access,which can support the sporadic access of massive devices(more than one million devices)with limited ***,an advanced receiver algorithm is designed to solve the optimal solutions for the proposed scheme,which utilizes various prior information to enhance the *** specific,the joint sparsity between the channel and data is used to improve the accuracy of pilot detection,and the information of modulation and cyclic redundancy check is exploited for channel correction to improve the performance of data *** simulation results show that the proposed scheme can achieve improved active user detection performance and data recovery accuracy than existing methods.

关键词： massive machine-type communication nonorthogonal access compressive sensing contention based access

Optimized Selection Method of Air Combat Course of Action under Stochastic Uncertainty

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 494-518页

作者： yun zhong Jieyong Zhang Peng Sun Lujun Wan Kepeng Wang Information and Navigation College Air Force Engineering UniversityXi’an710077China Equipment Management and Unmanned Aerial Vehicle Engineering College Air Force Engineering UniversityXi’an710051China Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710051China Unit 94040 of PLA Korla841000China

Aiming at the design problem of aviation swarm combat course of action(COA),considering the influence of stochastic parameters in the causal relationship model and optimization problem model,according to the dynamic influence net(DIN)theory,stochastic simulation technique,feedforward neural network(FNN)function approximation technique and multi-objective artificial fish school algorithm(MOAFSA),this paper proposed a COA optimized method based on DIN and multi-objective stochastic chance constraint optimization for aviation swarm ***,on the basis of establishing the overall framework of the model and defining the elements of causal relationship modeling,the static and dynamic causal relationship modeling and optimization problem modeling were carried out ***,the probability propagation mechanism of DIN was established,which mainly included two aspects,i.e.,the overall process and the specific ***,input and output data were generated based on stochastic *** to these data,FNN was adopted for function approximation,and MOAFSA was adopted for iterative ***,the rationality of the model,and the effectiveness and superiority of the algorithm were verified through multiple sets of simulation cases.

关键词： Stochastic uncertainty aviation swarm stochastic simulation course of action feedforward neural network multi-objective artificial fish school algorithm

A novel method for synthesis of styryl phosphonate monoester and its application in La(Ⅲ) extraction

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Journal of Rare Earths 2020年第6期38卷 649-656页

作者： Kaihua Huang yun Jia Shuai Wang Jia Yang Hong zhong College of Chemistry and Chemical Engineering Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese ResourcesCentral South UniversityChangsha 410083China

Herein,styryl phosphonate monoester(SPE) was synthesized and first introduced as rare earth *** solvent extraction of lanthanum(Ⅲ) from nitrate solution using styryl phosphonate mono-isooctyl ester(SPE108),di-2-ethylhexyl phosphoric acid(D2 EHPA) and 2-ethylhexyl phosphonic acidmono-2-ethylhexyl ester(EHEHPA) as extractants was *** effects of experimental parameters including equilibrium time,extractant concentration,aqueous pH,phase ratio and salt concentration on the extraction process were *** results indicate that the extraction ability and capacity of the extractants follow the order:SPE108> D2 EHPA> ***’s more,the extraction process is less affected by ammonium sulfate in the aqueous phase with *** results of the separation between lanthanum and adjacent lanthanides(Ce,Pr,Nd,Sm) show that SPE108 can separate lanthanides efficiently at low *** extraction mechanism of SPE108 is proved to be similar to D2 EHPA,and the density functional theory(DFT) calculation results infer that SPE108 exhibits superior extraction ability due to its strong electron-accepting ability.

关键词： Styryl phosphonate monoester Rare earth Extraction Extractant

Supervised Contrastive Learning with Term Weighting for Improving Chinese Text Classification

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Tsinghua Science and Technology 2023年第1期28卷 59-68页

作者： Jiabao Guo bo Zhao Hui Liu Yifan Liu Qian zhong School of Cyber Science and Engineering Wuhan UniversityWuhan 430000China

With the rapid growth of information retrieval technology,Chinese text classification,which is the basis of information content security,has become a widely discussed *** view of the huge difference compared with English,Chinese text task is more complex in semantic information ***,most existing Chinese text classification approaches typically regard feature representation and feature selection as the key points,but fail to take into account the learning strategy that adapts to the ***,these approaches compress the Chinese word into a representation vector,without considering the distribution of the term among the categories of *** order to improve the effect of Chinese text classification,a unified method,called Supervised Contrastive Learning with Term Weighting(SCL-TW),is proposed in this *** contrastive learning makes full use of a large amount of unlabeled data to improve model *** SCL-TW,we calculate the score of term weighting to optimize the process of data augmentation of Chinese ***,the transformed features are fed into a temporal convolution network to conduct feature *** verifications are conducted on two Chinese benchmark *** results demonstrate that SCL-TW outperforms other advanced Chinese text classification approaches by an amazing margin.

关键词： Chinese text classification Supervised Contrastive Learning(SCL) Term Weighting(TW) Temporal Convolution Network(TCN)

Rh single atoms embedded in CeO_(2) nanostructure boost CO_(2) hydrogenation to HCOOH

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Chinese Journal of Chemical Engineering 2022年第3期35卷 62-69页

作者： bo Wu Xing Yu Min Huang Liangshu zhong Yuhan Sun CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

CO_(2)hydrogenation to value-added chemicals is a promising pathway to solve CO_(2)-relevant environmental problems but still remains a great ***,we report a CeO_(2)nanostructure supported Rh single atoms(Rh-SAs/CeO_(2))catalyst and was used for the efficient CO_(2)hydrogenation to *** Rh-SAs/CeO_(2)exhibited high catalytic activity with turnover numbers(TON)up to 221 at 200℃,which was 4-fold to that of CeO_(2)supported Rh nanoparticles(Rh-NPs/CeO_(2)).Moreover,HCOOH selectivity for Rh-SAs/CeO_(2)reached 85%,much higher than that of Rh-NPs/CeO_(2)(46%).Mechanism studies revealed that Rh single atoms in the Rh-SAs/CeO_(2)with high metal atoms utilization efficiency not only provided abundant active sites to promote the catalytic activity,but also suppressed the decomposition of HCOOH to CO and benefited the formation of HCOOH.

关键词： CO_(2)hydrogenation Selectivity Single-atom catalysts(SACs) Rh HCOOH

Hysteretic behavior of cambered surface steel tube damper:Theoretical and experimental research

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Frontiers of Structural and Civil Engineering 2023年第4期17卷 606-624页

作者： Jiale LI yun ZHOU Zhiming HE Genquan zhong Chao ZHANG Department of Civil Engineering Guangzhou UniversityGuangzhou 510006China Department of Civil&Transportation Engineering Guangdong University of TechnologyGuangzhou 510006China

A novel cambered surface steel tube damper(CSTD)with a cambered surface steel tube and two concave connecting plates is proposed *** steel tube is the main energy dissipation component and comprises a weakened segment in the middle,a transition segment,and an embedded *** is believed that during an earthquake,the middle weakened segment of the CSTD will be damaged,whereas the reliability of the end connection is *** and experimental studies are conducted to verify the effectiveness of the proposed *** for the initial stiffness and yield force of the CSTD are ***,two CSTD specimens with different steel tube thicknesses are fabricated and tested under cyclic quasi-static *** result shows that the CSTD yields a stable hysteretic response and affords excellent energy dissipation.A parametric study is conducted to investigate the effects of the steel tube height,diameter,and thickness on the seismic performance of the *** with equalstiffness design steel tube dampers,the CSTD exhibits better energy dissipation performance,more stable hysteretic response,and better uniformity in plastic deformation distributions.

关键词： cambered surface steel tube damper energy dissipation capacity finite element model hysteretic performance parametric study

Comparative study on pyrolysis of bamboo in microwave pyrolysis-reforming reaction by binary compound impregnation and chemical liquid deposition modified HZSM-5

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Journal of Environmental Sciences 2020年第8期32卷 186-196页

作者： Haoran Du Zhaoping zhong bo Zhang Kun Shi Zhaoying Li Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education Southeast UniversityJiangsu 210096China

The deactivation of catalyst is a significant reason for its limited application during the catalytic fast pyrolysis(CFP)*** reduce the coke formation,binary compound impregnation(BCI)and chemical liquid deposition(CLD)were used to modify HZSM-5 *** the same time,the self-designed microwave reactor separated the pyrolysis of bamboo and catalytic upgrading of primary vapor,which made the catalytic effect more *** results indicated that CLD used TiO 2 deposition to cover external acid sites,while BCI by phosphorus-nickel could cover and partly destroy superficial acid sites through two different *** the scope of the loaded amount studied,the yield of aromatic hydrocarbons in the oil phase increased at first and then decreased,while the coke formation reduced ***(benzene,toluene and xylene),the most valuable product in bio-oil,drastically increased by 39.1%and 22.6%respectively over the CLD and BCI modified *** the catalytic performance as well as cost,CLD over HZSM-5 has more advantages in the CFP process to upgrade bio-oil.

关键词： Bamboo Modified HZSM-5 Microwave Binary compound impregnation Chemical liquid deposition

A characteristic modeling method of error-free compression for nonlinear systems

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Control Theory and Technology 2021年第3期19卷 375-383页

作者： Bin Meng yun-bo Zhao Jing-Jing Mu Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijingChina Department of Automation University of Science and Technology of ChinaBeijingChina China Aerospace Science and Technology Corporation BeijingChina

The existence of error when compressing nonlinear functions into the coefficients of the characteristic model is known to be a key issue in existing characteristic modeling approaches,which is solved in this work by an error-free compression *** first define a key concept of relevant states with corresponding compressing methods into their coefficients,where the coefficients are continuous and bounded and the compression is ***,we give the conditions for decoupling characteristic modeling for MIMO systems,and sequentially,we establish characteristic models for nonlinear systems with minimum phase and relative order two as well as the flexible spacecrafts,realizing the equivalence in the characteristic model ***,we explicitly explain the reasons for normalization in the characteristic model theory.

关键词： Characteristic modeling Relevant states Error-free compression Flexible spacecraft Normalization