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Reconstruction of dynamic structures of experimental setups based on measurable experimental data only

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Chinese Physics B 2018年第3期27卷 177-183页

作者： Tian-Yu Chen Yang Chen hu-Jiang Yang Jing-hua Xiao Gang hu School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Physics Beijing Normal UniversityBeijing 100875China

Nowadays,massive amounts of data have been accumulated in various and wide fields,it has become today one of the central issues in interdisciplinary fields to analyze existing data and extract as much useful information as possible from *** is often that the output data of systems are measurable while dynamic structures producing these data are hidden,and thus studies to reveal system structures by analyzing available data,i.e.,reconstructions of systems become one of the most important tasks of information *** the past,most of the works in this respect were based on theoretical analyses and numerical *** analyses of experimental data are very *** physical science,most of the analyses of experimental setups were based on the first principles of physics laws,i.e.,so-called top-down *** this paper,we conducted an experiment of"Boer resonant instrument for forced vibration"(BRIFV)and inferred the dynamic structure of the experimental set purely from the analysis of the measurable experimental data,i.e.,by applying the bottom-up *** of the experimental set is strongly nonlinear and chaotic,and it's subjects to inevitable *** proposed to use high-order correlation computations to treat nonlinear dynamics;use two-time correlations to treat noise *** applying these approaches,we have successfully reconstructed the structure of the experimental setup,and the dynamic system reconstructed with the measured data reproduces good experimental results in a wide range of parameters.

关键词： dynamics inverse problem data analysis

Simulation of Land-use Scenarios for Beijing Using CLUE-S and Markov Composite Models

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Chinese Geographical Science 2013年第1期23卷 92-100页

作者： hu Yecui ZHENG Yunmei ZHENG Xinqi School of Land Science & Technique China University of Geosciences Key Laboratory of Land Consolidation Ministry of Land and Resources

This study investigated and simulated land use patterns in Beijing for the year 2000 and the year 2005 from the actual land use data for the year 1995 and the year 2000,respectively,by combining spatial land allocation simulation using the CLUE-S model,and numerical land demand prediction using the Markov *** simulations for 2000 and 2005 were confirmed to be generally accurate using Kappa *** the land-use scenarios for Beijing in 2015 were simulated assuming two modes of development:1) urban development following existing trends;and 2) under a strict farmland *** simulations suggested that under either mode,urbanized areas would expand at the expense of land for other *** expansion was predicted to dominate the land-use conversions between 2005 and 2015,and was expected to be accompanied by an extensive loss of *** key susceptible to land-use changes were found to be located at the central urban Beijing and the surrounding regions including Yanqing County,Changping District and Fangshan ***,the simulations predicted a considerable expansion of urban/suburban areas in the mountainous regions of Beijing,suggesting a need for priority monitoring and protection.

关键词： CLUE-S model land use Markov model scenario simulation Beijing

Toward automatic estimation of urban green volume using airborne LiDAR data and high resolution Remote Sensing images

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Frontiers of Earth Science 2013年第1期7卷 43-54页

作者： Yan huANG Bailang YU Jianhua ZHOU chunlin hu Wenqi TAN Zhiming hu Jianping WU Key Laboratory of Geographic Information Science (Ministry of Education) East China Normal University Shanghai 200241 China Shanghai Landscape and City Appearance Administration Information Center Shanghai 200040 China

Urban green volume is an important indicator for analyzing urban vegetation structure, ecological evaluation, and green-economic estimation. This paper proposes an object-based method for automated estimation of urban green volume combining three-dimensional （3D） information from airborne Light Detection and Ranging （LiDAR） data and vegetation information from high resolution remotely sensed images through a case study of the Lujiazui region, Shanghai, China. High resolution airborne near-infrared photographs are used for identifying the urban vegetation distribution. Airborne LiDAR data offer the possibility to extract individual trees and to measure the attributes of trees, such as tree height and crown diameter. In this study, individual trees and grassland are identified as the independent objects of urban vegetation, and the urban green volume is computed as the sum of two broad portions： individual trees volume and grassland volume. The method consists of following steps： generating and filtering the normalized digital surface model （nDSM）, extracting the nDSM of urban vegetation based on the Normalized Difference Vegetation Index （NDVI）, locating the local maxima points, segment- ing the vegetation objects of individual tree crowns and grassland, and calculating the urban green volume of each vegetation object. The results show the quantity and distribution characteristics of urban green volume in the Lujiazui region, and provide valuable parameters for urban green planning and management. It is also concluded from this paper that the integrated application of LiDAR data and image data presents an effective way to estimate urban green volume.

关键词： Urban areas Vegetation mapping Remote sensing Environmental quality

All-Climate Aluminum-Ion Batteries Based on Binder-Free MOF-Derived FeS_(2)@C/CNT Cathode

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Nano-Micro Letters 2021年第10期13卷 276-287页

作者： Yuxiang hu hongjiao huang Deshuang Yu Xinyi Wang Linlin Li Han hu Xiaobo Zhu Shengjie Peng Lianzhou Wang Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandBrisbaneQueensland 4072Australia Jiangsu Key Laboratory of Electrochemical Energy Storage Technologies College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 211106People’s Republic of China State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringUniversity of Petroleum(East China)Qingdao 266580People’s Republic of China

Aluminum-ion batteries(AIBs)are promising next-generation batteries systems because of their features of low cost and abundant aluminum ***,the inferior rate capacity and poor all-climate performance,especially the decayed capacity under low temperature,are still critical challenges toward high-specific-capacity ***,we report a binder-free and freestanding metal-organic framework-derived FeS_(2)@C/carbon nanotube(FeS_(2)@C/CNT)as a novel all-climate cathode in AIBs working under a wide temperature window between−25 and 50℃ with exceptional *** resultant cathode not only drastically suppresses the side reaction and volu-metric expansion with high capacity and long-term stability but also greatly enhances the kinetic process in AIBs with remarkable rate capacity(above 151 mAh g^(−1) at 2 A g^(−1))at room *** importantly,to break the bottleneck of the inherently low capacity in graphitic material-based all-climate AIBs,the new hierarchical conductive composite FeS_(2)@C/CNT highly promotes the all-climate performance and delivers as high as 117 mAh g^(−1) capacity even under−25°*** well-designed metal sulfide electrode with remarkable performance paves a new way toward all-climate and flexible AIBs.

关键词： Aluminum-ion battery All-climate battery Iron sulfide Binder-free High rate capacity

Synthesis of 9-Substituted Berberine Derivatives with Microwave Irradiation

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Chemical Research in Chinese Universities 2018年第4期34卷 571-577页

作者： HAN Xie SHAO Kaiyuan hu Wenxiang School of Chemical Engineering and Pharmacy Wuhan Institute of Technology Wuhan 430000 P. R. China Jingdong Xianghu Microwave Chemistry Union Laboratory Beijing Excalibur Space Military Academy of Medical Sciences Belling 101601 P. R. China Space Systems Division Strategic' Support Troops Chinese People's Liberation Army Beijing 100101 P. R. China

Hyperglycemia is frequently accompanying with hyperlipidemia. To explore the potent drugs with dual-activity and dual-site effects that could reduce blood glucose and blood lipid at the same time, fibrate group with lipid-lowering effect on the 9th position of berberine（BBR） was introduced using the drug design combination principle and the multi-target collaborative treatment method, Moreover, the molecular structure of BBR was modified, and six 9-substituted derivatives of BBR were designed and synthesized, among which, five compotmds have never been reported before. In addition, the molecular structttres of these derivatives were identified using liquid chromato- graphy-mass spectrometry（LC-MS）, IH nuclear n^tgnetic resonance（1H NMR） and 13C NMR, respectively. Fu^her- more, the microwave irradiation experimental technique was applied in the synthesis reaction using the novel micro- wave synthesizer, which accelerated the reaction rate, enhanced the reaction yield, reduced the reaction by-products, and simplified the post-processing steps. In the meantime, the 9-position regioselective demethylation of BBR was explored through quantum chemical calculation during the synthesis of berberrubine. The computations were consistent with the experimental results, which contributed to deducing the mechanism of its selective methylation.

关键词： Berberine derivative Microwave irradiation Quantum chemistry Regioselectivity

Quadrature-free spline method for two-dimensional Navier-Stokes equation

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 31-42页

作者： hu Xian-liang HAN Dan-fu Dept. of Math. Zhejiang Univ. Hangzhou 310027 China.

In this paper, a quadrature-free scheme of spline method for two-dimensional Navier- Stokes equation is derived, which can dramatically improve the efficiency of spline method for fluid problems proposed by Lai and Wenston（2004）. Additionally, the explicit formulation for boundary condition with up to second order derivatives is presented. The numerical simulations on several benchmark problems show that the scheme is very efficient.

关键词： quadrature-free spline method Navier-Stokes equation.

Prognostic prediction in gastric cancer patients without serosal invasion: comparative study between UICC 7^(th) edition and JCGS 13^(th) edition N-classification systems

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Chinese Journal of Cancer Research 2014年第5期26卷 596-601页

作者： Xiang hu Liang Cao Yi Yu Department of General Surgery The First Affiliated HospitalDalian Medical University

Objective： T-stage and N-stage have been proven to be the most important factors influencing survival in gastric cancer patients, and have been accepted for use in the Japanese Classification of Gastric Carcinoma（JCGC） and the Union International Cancer Control（UICC-TNM） staging systems. The purpose of this study was to compare the prognostic values of the different N classification systems in gastric cancer patients without serosal ***： We retrospectively compared the clinicopathological results of 1,115 patients with primary gastric cancer who underwent curative gastric resection.Results： Serosal invasion was identified in 212 of 1,115 patients（19.0%）, and it was associated with lymph node metastasis according to the JCGC^13th（P〈0.001） and TNM^7th（P〈0.001） systems. The 5-year survival rate for the serosal invasion-negative patients（78.2%） was significantly higher than that for the serosal invasion-positive patients（31.1%）（P〈0.001）. Multivariate Cox regression survival analysis showed that depth of invasion（P=0.013）, 13 th JCGC PN stage（P〈0.001）, and 7th TNM PN stage（P〈0.001） were independent prognostic factors for serosal invasion-negative gastric cancer patients.Conclusions： The prognosis of gastric cancer patients with serosal invasion is very poor. Both the 13 th JCGC and 7th TNM N-staging systems were able to accurately estimate the prognosis of gastric cancer patients, but the 7th TNM system was simpler and easier to use.

关键词： Gastric cancer serosal invasion depth of invasion lymph node metastasis

V2I Physical Layer Security Beamforming with Antenna Hardware Impairments under RIS Assistance

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Computers, Materials & Continua 2024年第10期81卷 1835-1854页

作者： Zerong Tang Tiecheng Song Jing hu School of Information Science and Engineering Southeast UniversityNanjing210096China

The Internet of Vehicles(IoV)will carry a large amount of security and privacy-related data,which makes the secure communication between the IoV terminals increasingly *** paper studies the joint beamforming for physical-layer security transmission in the coexistence of Vehicle-to-Infrastructure(V2I)and Vehicle-toVehicle(V2V)communication with Reconfigurable Intelligent Surface(RIS)assistance,taking into account hardware impairments.A communication model for physical-layer security transmission is established when the eavesdropping user is present and the base station antenna has hardware impairments assisted by *** on this model,we propose to maximize the V2I physical-layer security transmission *** solve the coupled non-convex optimization problem,an alternating optimization algorithm based on second-order cone programming and semidefinite relaxation is proposed to obtain the optimal V2I base station transmit precoding and RIS reflect phase shift ***,simulation results are presented to verify the convergence and superiority of our proposed algorithm while analyzing the impact of system parameters on the V2I physical-layer security transmission *** simulation results further demonstrate that the proposed robust beamforming algorithm considering hardware impairments will achieve an average performance improvement of 0.7 dB over a non-robustly designed ***,increasing the number of RIS reflective units from 10 to 50 results in an almost 2 dB enhancement in secure transmission rate.

关键词： Internet of vehicle reconfigurable intelligent surface physical-layer security transmission antenna hardware impairments

Therapeutic application of hydrogen sulfide donors： the potential and challenges

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Frontiers of Medicine 2016年第1期10卷 18-27页

作者： Dan Wu Qingxun hu Yizhun Zhu Department of Pharmacology School of Pharmacy Fudan University Shanghai 201203 China Department of Pharmacy Tongji Hospital Tongji University Sc-hool of Meclicine Shanghai 200065 China

Hydrogen sulfide （HeS）, a colorless gas smelling of rotten egg, has long been considered a toxic gas and environment hazard. However, evidences show that H2S plays a great role in many physiological and pathological activities, and it exhibits different effects when applied at various doses. In this review, we summarize the chemistry and biomedical applications of H2S-releasing compounds, including inorganic salts, phosphorodithioate derivatives, derivatives of Allium sativum extracts, derivatives of thioaminoacids, and derivatives of anti- inflammatory drugs.

关键词： hydrogen sulfide cardiovascular cancer hypertension