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Dense Mapping From an Accurate Tracking SLAM

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IEEE/CAA Journal of Automatica Sinica 2020年第6期7卷 1565-1574页

作者： Weijie huang guoshan Zhang Xiaowei Han School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China Institute of Information Engineering Shenyang UniversityShenyang 110044China

In recent years, reconstructing a sparse map from a simultaneous localization and mapping(SLAM) system on a conventional CPU has undergone remarkable progress. However,obtaining a dense map from the system often requires a highperformance GPU to accelerate computation. This paper proposes a dense mapping approach which can remove outliers and obtain a clean 3D model using a CPU in real-time. The dense mapping approach processes keyframes and establishes data association by using multi-threading technology. The outliers are removed by changing detections of associated vertices between keyframes. The implicit surface data of inliers is represented by a truncated signed distance function and fused with an adaptive weight. A global hash table and a local hash table are used to store and retrieve surface data for data-reuse. Experiment results show that the proposed approach can precisely remove the outliers in scene and obtain a dense 3D map with a better visual effect in real-time.

关键词： Adaptive weights data association dense mapping hash table simultaneous localization and mapping(SLAM)

Path Planning for Intelligent Robots Based on Deep Q-learning With Experience Replay and Heuristic Knowledge

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1179-1189页

作者： Lan Jiang Hongyun huang Zuohua Ding the Laboratory of Intelligent Computing and Software Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China the Center of Multi-Media Big Data of Library Zhejiang Sci-Tech UniversityHangzhou 310018China

Path planning and obstacle avoidance are two challenging problems in the study of intelligent robots. In this paper, we develop a new method to alleviate these problems based on deep Q-learning with experience replay and heuristic knowledge. In this method, a neural network has been used to resolve the "curse of dimensionality" issue of the Q-table in reinforcement learning. When a robot is walking in an unknown environment, it collects experience data which is used for training a neural network;such a process is called experience *** knowledge helps the robot avoid blind exploration and provides more effective data for training the neural network. The simulation results show that in comparison with the existing methods, our method can converge to an optimal action strategy with less time and can explore a path in an unknown environment with fewer steps and larger average reward.

关键词： Deep Q-learning(DQL) experience replay(ER) heuristic knowledge(HK) path planning

A partial information linear-quadratic optimal control problem of backward stochastic differential equation with its applications

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Science China(Information Sciences) 2020年第9期63卷 188-200页

作者： Pengyan huang Guangchen WANG Huanjun ZHANG School of Control Science and Engineering Shandong University

In this paper, we investigate a kind of partial information linear-quadratic optimal control problem driven by a backward stochastic differential equation, where the state equation and the cost functional contain diffusion terms. Using maximum principle, we derive the corresponding Hamiltonian system, which is a conditional mean-field forward-backward stochastic differential equation. By the backward separation approach and the filtering technique, we get two Riccati equations, and a backward and a forward optimal filtering equations. Then a feedback form of optimal control is obtained. We also extend the control problem to the case of mean-field backward stochastic differential equation under partial information. A corresponding feedback form of optimal control is also obtained.

关键词： backward stochastic differential equation feedback representation linear-quadratic optimal control mean-field optimal filter

Coupled Thermal and Mechanical Dynamic Performances of the Molten Salt Packed-Bed Thermal Energy Storage System

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Journal of Thermal Science 2022年第5期31卷 1337-1350页

作者： huang Lijuan DU Baocun LEI Yonggang College of Civil Engineering Taiyuan University of TechnologyTaiyuan030024China

In this paper,the thermal and mechanical dynamic performances of molten salt packed-bed thermal energy storage(TES)system are investigated by coupling Finite Volume Method(FVM)and Finite Element Method(FEM).Firstly,an integration model coupling FVM and FEM in packed-bed tank is ***,the pore water static pressure caused by the liquid level of molten salt is applied in the coupled *** on this model,the dynamic characteristics of thermal and stress distributions are ***,the effects of porosity,inlet temperature and velocity on the thermal and stress performances are *** results indicate that the temperature and stress of the wall increase during the discharging process,and the peak stress occurs at the tank bottom connecting with the ground *** method of increasing porosity is helpful to improve the discharging power,but the plastic failure on the wall would probably occur due to the higher stress *** inlet temperature has negative influence on the thermal and safety performances,because lower discharging power and higher stress would be produced *** the lower stress can be achieved when the higher inlet velocity is adopted,the effective discharge time would be decreased significantly.

关键词： solar power thermal energy storage packed-bed dynamic performance stress

Development of High Performance Liquid Chromatography-Tandem Mass Spectrometry Method for the Detection of Tulathromycin in Swine Plasma

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Journal of Integrative Agriculture 2012年第3期11卷 465-473页

作者： huang Xian-hui ZHAO Yong-da HE Li-min LIANG Zi-sen guo Li-li ZENG Zhen-ling CHEN ZHANG-liu ZHANG Min FANG Bing-hu National Reference Laboratory of Veterinary Drug Residues College of Veterinary Medicine South China Agricultural UniversityGuangzhou 510642 P.R. China Qingdao Conyinent Phaimaceutical Co. Ltd. Qingdao 266061 P.R. China

An accurate and precise method for the determination of tulathromycin in swine plasma was developed and *** samples were analyzed by high-performance liquid chromatography with tandem mass spectrometry detection （HPLC-MS/MS） using electrospray ionization （ESI）.Tulathromycin was extracted from plasma by precipitation with acetonitrile and separated using a Phenomenex Luna 5 μm C18 column （150 mm×2.0 mm） at a flow rate of 0.25 mL min^-*** A consisted of 0.002 mol L^-1 ammonium acetate and formic acid （999：1,v/v）,and solvent B was *** mass spectrometer was operated in the selected-ion mode with atmospheric pressure chemical ionization to monitor the respective MH＋ ions,namely,m/z 577.3 for tulathromycin and m/z 679.3 for the internal standard *** calibration curves were linear in a dynamic range of 2.0-500 ng mL^-1 on the *** accuracy was ranged from 95.25 to 109.75%,and the precision was ranged from 2.81 to 7.72%.The recoveries measured at 3 concentration levels （20,250,and 500 ng mL^-1） were higher than 98%.The method described above is efficient,and has the required accuracy and precision for rapid determination of tulathromycin in *** method was applied to study the pharmacokinetics of tulathromycin in swine,and tulathromycin demonstrated a rapid absorption,wide distribution,and slow elimination after intramuscular administration.

关键词： tulathromycin drug assay pharmacokinetics plasma swine HPLC-MS/MS

An efficient approach for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic excitations

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 677-690页

作者： huang Huan Li Yingxiong Li Yuyu College of Water Conservancy and Civil Engineering South China Agricultural UniversityGuangzhou 510642China Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 611756China

An efficient approach is proposed for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic *** concentrated plastic hinges,described by the Bouc-Wen model,are assumed to occur at the two ends of a linear-elastic beam *** auxiliary differential equations governing the plastic rotational displacements and their corresponding hysteretic displacements are replaced with linearized differential ***,the two sets of equations of motion for the original nonlinear system can be reduced to an expanded-order equivalent linearized equation of motion for equivalent linear *** solve the equation of motion for equivalent linear systems,the nonstationary random vibration analysis is carried out based on the explicit time-domain method with high ***,the proposed treatment method for initial values of equivalent parameters is investigated in conjunction with parallel computing technology,which provides a new way of obtaining the equivalent linear systems at different time *** on the explicit time-domain method,the key responses of interest of the converged equivalent linear system can be calculated through dimension reduction analysis with high *** examples indicate that the proposed approach has high computational efficiency,and shows good applicability to weak nonlinear and medium-intensity nonlinear systems.

关键词： nonstationary random vibration plastic hinge equivalent linearization method explicit time-domain method parallel computation

Hardening-Softening Constitutive Model of Hard Brittle Rocks Considering Dilatant Effects and Safety Evaluation Index

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Acta Mechanica Solida Sinica 2020年第1期33卷 121-140页

作者： Shuling huang Chuanqing Zhang Xiuli Ding Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Yangtze River Scientific Research InstituteWuhan 430071HubeiChina State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071HubeiChina University of Chinese Academy of Sciences Beijing 100049China

The damage and even failure of hard brittle rocks has been the most important challenge facing the safety of construction of deep engineering works,so the key to solving this problem is the recognition of the strength characteristics and description of the mechanical behavior of hard brittle ***,in view of this problem,in this study,we first analyzed the strength and mechanical response characteristics revealed in tests of,and site excavation in,hard brittle ***,by analyzing rock-strength envelopes on meridional and deviatoric planes,the generalized polyaxial strain energy(GPSE)strength criterion was *** allows description of the effects of the minimum principal stress,intermediate principal stress,hydrostatic pressure,and Lode’s angle of stress on the strength of hard *** establishing evolutionary relationships of strength parameters and dilation parameters with plastic volumetric strain in rock failure,we established an elasto-plastic mechanical constitutive model for hard brittle rocks based on the GPSE *** addition,through use of the failure approach index theory and the dilatancy safety factor,an evaluation index for degree of damage considering dilatant effects of rocks was ***,the constitutive model established in this study and the proposed evaluation index were integrated into the numerical simulation method to simulate triaxial tests on rocks and numerical simulation of deformation and fracture of the rocks surrounding the deep-buried auxiliary tunnels in China’s Jinping II Hydropower *** this way,the reasonableness of the model and the index was *** strength theory and the constitutive model established in this research are applicable to the analysis of high-stress deformation and fracture of hard brittle rock masses,which supports the theoretical work related to deep engineering operations.

关键词： Hard brittle rock.Constitutive model Safety evaluation index.Dilatant effect Strength criterion

Correlation of fibrinogen-like protein 2 with progression of acute pancreatitis in rats

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World Journal of Gastroenterology 2013年第16期19卷 2492-2500页

作者： Xiao-Hua Ye Tan-Zhou Chen Jia-Ping Huai Guang-Rong Lu Xiao-Ju Zhuge Ren-Pin Chen Wu-Jie Chen Chen Wang zhi-Ming huang Department of Gastroenterology and Hepatology First Affiliated Hospital of Wenzhou Medical College

AIM: To examine fibrinogen-like protein 2 (fgl2) expression during taurocholate-induced acute pancreatitis progression in rats and its correlation with pancreatic injury severity. METHODS: Forty-eight male Sprague-Dawley rats were randomly divided into the severe acute pancreatitis (SAP) group (n = 24) and the sham operation (SO) group (n = 24). Sodium taurocholate (4% at doses of 1 mL/kg body weight) was retrogradely injected into the biliopancreatic ducts of the rats to induce SAP. Pancreatic tissues were prepared immediately after sacrifice. At the time of sacrifice, blood was obtained for determination of serum amylase activity and isolation of peripheral blood mononuclear cells (PBMCs). Pancreatic tissue specimens were obtained for routine light microscopy including hematoxylin and eosin staining, and the severity of pancreatic injury was evaluated 1, 4 and 8 h after induction. Expression of fgl2 mRNA was measured in the pancreas and PBMCs using reverse transcription polymerase chain reaction. Expression of fgl2 protein was evaluated in pancreatic tissues using Western blotting and immunohistochemical staining. Masson staining was also performed to observe microthrombosis. RESULTS: At each time point, levels of fgl2 mRNAs in pancreatic tissues and PBMCs were higher (P < 0.05) in the SAP group than in the SO group. For pancreatic tissue in SAP vs SO, the levels were: after 1 h, 3.911 ± 1.277 vs 1.000 ± 0.673; after 4 h, 9.850 ± 3.095 vs 1.136 ± 0.609; and after 8 h, 12.870 ± 3.046 vs 1.177 ± 0.458. For PBMCs in SAP vs SO, the levels were: after 1 h, 2.678 ± 1.509 vs 1.000 ± 0.965; after 4 h, 6.922 ± 1.984 vs 1.051 ± 0.781; and after 8 h, 13.533 ± 6.575 vs 1.306 ± 1.179. Levels of fgl2 protein expression as determined by Western blotting and immunohistochemical staining were markedly up-regulated (P < 0.001) in the SAP group compared with those in the SO group. For Western blotting in SAP vs SO, the results were: after 1 h, 2.183 ± 0.115 vs 1.110 ± 0.158; after 4

关键词： Fibrinogen-like protein 2 Microthrombosis Fibrin Severe acute pancreatitis Peripheral blood mononuclear cell

Cipatrijugin G,a new trijugin-type limonoid bearing an uncommonγ-hydroxybutenolide unit from the aerial parts of Cipadessa cinerascens

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Natural Products and Bioprospecting 2013年第6期3卷 267-270页

作者： Cheng-Shi JIANG Yan LI Zhen-Zhong WANG Xiao-Yin huang Wei XIAO Yue-Wei guo State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Jiangsu Kanion Pharmaceutical Co.Ltd. Lianyungang 222001China

A new trijugin-type limonoid,cipatrijugin G(1),together with the related known cipatrijugin A(2),were isolated from the aerial parts of Cipadessa *** structure of the new compound was determined by extensive analysis of its spectroscopic data and by comparison of its NMR data with those reported in the *** 1 showed cytotoxicity against tumor cell line A549 with an IC_(50) value of 9.78μ*** is the first report of a trijugin-type limonoid bearing aγ-hydroxybutenolide unit,in comparison to the common furan unit as ring E.

关键词： Cipadessa cinerascens trijugin-type limonoid