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Single View Based Measurement on Space Planes

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Journal of Computer Science & Technology 2004年第3期19卷 374-382页

作者： guang-HuiWang zhan-YiHu Fu-ChaoWu NationalLaboratoryofPatternRecognition InstituteofAutomationTheChineseAcademyofSciencesBeijing100080P.R.China

The plane metrology using a single uncalibrated image is studied in the paper, and three novel approaches are proposed. The first approach, namely key-line-based method, is an improvement over the widely used key-point-based method, which uses line correspondences directly to compute homography between the world plane and its image so as to increase the computational accuracy. The second and third approaches are both based on a pair of vanishing points from two orthogonal sets of parallel lines in the space plane together with two unparallel referential distances, but the two methods deal with the problem in different ways. One is from the algebraic viewpoint which first maps the image points to an affine space via a transformation constructed from the vanishing points, and then computes the metric distance according to the relationship between the affine space and the Euclidean space, while the other is from the geometrical viewpoint based on the invariance of cross ratios. The second and third methods avoid the selection of control points and are widely applicable. In addition, a brief description on how to retrieve other geometrical entities on the space plane, such as distance from a point to a line, angle formed by two lines, etc., is also presented in the paper. Extensive experiments on simulated data as well as on real images show that the first and the second approaches are of better precision and stronger robustness than the key-point-based one and the third one, since these two approaches are fundamentally based on line information.

关键词： single view metrology projective geometry geometrical parameter retrieval plane homography

UAV maneuvering decision-making algorithm based on deep reinforcement learning under the guidance of expert experience

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Journal of Systems Engineering and Electronics 2024年第3期35卷 644-665页

作者： zhan guang zhanG Kun LI Ke PIAO Haiyin School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Electro-Optic Control Laboratory Luoyang 471009China

Autonomous umanned aerial vehicle(UAV) manipulation is necessary for the defense department to execute tactical missions given by commanders in the future unmanned battlefield. A large amount of research has been devoted to improving the autonomous decision-making ability of UAV in an interactive environment, where finding the optimal maneuvering decisionmaking policy became one of the key issues for enabling the intelligence of UAV. In this paper, we propose a maneuvering decision-making algorithm for autonomous air-delivery based on deep reinforcement learning under the guidance of expert experience. Specifically, we refine the guidance towards area and guidance towards specific point tasks for the air-delivery process based on the traditional air-to-surface fire control ***, we construct the UAV maneuvering decision-making model based on Markov decision processes(MDPs). Specifically, we present a reward shaping method for the guidance towards area and guidance towards specific point tasks using potential-based function and expert-guided advice. The proposed algorithm could accelerate the convergence of the maneuvering decision-making policy and increase the stability of the policy in terms of the output during the later stage of training process. The effectiveness of the proposed maneuvering decision-making policy is illustrated by the curves of training parameters and extensive experimental results for testing the trained policy.

关键词： unmanned aerial vehicle(UAV) maneuvering decision-making autonomous air-delivery deep reinforcement learning reward shaping expert experience

The recent advances in constructing designed electrode in lithium metal batteries

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Chinese Chemical Letters 2017年第12期28卷 2171-2179页

作者： Jiecheng Cui Tian-guang zhan Kang-Da zhang Dong Chen Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Life ScienceZhejiang Normal UniversityJinhua 321004China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China

Lithium metal battery, one of the most promising candidates for high-energy-density storage system, has attracted extensive interest due to its extremely high theoretical specific capacity, low gravimetric density and lowest negative redox potential. However, the formation of lithium dendrites, uncontrolled interfacial reactions, and huge volume change during the cycles of charging and discharging lower the Coulombic efficiency and cause harsh safety issues; they are the major hurdles towards the practical applications of lithium metal batteries. This review presents the recent advances in lithium metal battery and focuses on the functional hybrid electrodes, which are constructed to boost the electrochemical performance of metallic lithium and suppress the growth of lithium dendrites. Their general design rules, fabrication strategies, enhanced performances, and potential applications are summarized and analyzed. An outlook of the challenges and the potentials of lithium metal battery is also provided, which facilitates the future development of lithium metal batteries

关键词： Lithium metal batteryLithium dendritesFunctional lithium electrodeUniform depositionEnergy storage materials

Synthesis,properties,and self-assembly of 2,3-bis(n-octyl)hexaazatriphenylene

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Chinese Chemical Letters 2013年第6期24卷 453-456页

作者： Zhi-Gang Tao Tian-guang zhan Tian-You Zhou Xin Zhao zhan-Ting Li Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

A hexaazatriphenylene（HAT） derivative that bears two n-octyl chains was designed and *** photophysical and electrochemical properties have been *** study revealed that it could self-assemble into well-ordered 1D nan... 详细信息

关键词： Hexaazatriphenylene Self-assembly Microsheets Nanoribbons

Effect of Asynchronous Adjustments of Clamping Cylinders on Triangular Crack of Slab Castings Under Application of Soft Reduction

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Journal of Iron and Steel Research International 2013年第2期20卷 38-47页

作者： LIU Ke CHANG Yun-he HAN zhan-guang zhanG Jia-quan State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology Beijing

Soft reduction is known to be one of the best ways to improve the internal quality of slab castings such as center segregation, center porosity, centerline or triangular zone cracks, which is based on a proper adoption of the amount of reduction upon the given final solidification zone through roll gap adjustments. The synchronization of the clamping cylinders for roll gap adjustments should be very important to the application of soft reduction, including the synchronization of the clamping cylinders adjustments in the same and different segments. The synchronization of clamping cylinders adjustments is mainly affected by the adjustable accuracy of the four position-controlled clamping cylinders mounted in the upper frames of the segments according to a predetermined transformation relationship between the signals of displacement sensors and aimed roll gap, which, however, is also influenced by the installation accuracy, the precision of displacement sensors, the deformation of the segment frames and/or its bearing pedestals. Due to the actual asynchronous adjustments of the four clamping cylinders, the dynamic soft reduction operation is normally applied at non-ideal mechanical conditions. Here 7 possible situations of asynchronous adjustments of the local segments which may induce gap deviation have been presented. The roll gap deviation in the soft reduction region of a slab casting has been studied by a 3-D visco-elastic plastic FEM model, through which the additional inter-roll bulging, the related triangular cracks induced by one kind of the possible asynchronous adjustment situation and the effectiveness of soft reduction have been analyzed. A critical tolerance for the gap adjustments has been proposed for better contribution of soft reduction to the internal quality of slabs.

关键词： slab casting soft reduction clamping cylinder asynchronous adiustment

Charactering the spoilage mechanism of"three sticks"of Jinhua ham

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Food Science and Human Wellness 2022年第5期11卷 1322-1330页

作者： Changyu Zhou guang zhan Daodong Pan guanghong Zhou Ying Wang Jun He Jinxuan Cao State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Ningbo UniversityNingbo 315211China Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province Ningbo UniversityNingbo 315211China Key Laboratory of Meat Processing and Quality Control MOEKey Laboratory of Meat ProcessingMOAJiangsu Synergetic Innovation Center of Meat Processing and Quality ControlNanjing Agricultural UniversityNanjing 210095China

To investigate the spoilage characteristics of Jinhua ham,sensory scores,volatile compounds,biogenic amine,physicochemical parameters and microbial counts were evaluated between normal and spoiled *** results showed that off-odors of spoiled hams were dominated by rancid,sour,sulfide and ammonia odors derived from these compounds including butanoic acid,methanethiol and dimethyl *** content of biogenic amine in spoiled hams was significantly higher(more than 10-fold)compared with normal hams,and putrescine,cadaverine and histamine were the key components of biogenic amine of spoiled *** salt content,and higher moisture,TVB-N and thiobarbituric acid reactive substances(TBARS)values were observed in spoiled hams compared with normal *** populations of Enterobacteriaceae and Enterococcus of spoiled hams were obviously higher than that of normal *** moisture and low salt content caused the abnormal growth of Enterobacteriaceae and Enterococcus in spoiled hams,which contributed to the spoilage of Jinhua ham.

关键词： Jinhua ham Three sticks Spoilage Microbial counts Volatile compounds Biogenic amine

Comparative features of colorectal and gastric cancers with microsatellite instability in Chinese patients

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 647-653页

作者： Yan-qin HUANG Ying YUAN Wei-ting GE Han-guang HU Su-zhan zhanG Shu ZHENG Key Laboratory of Cancer Prevention and Intervention of Ministry of Education Key Laboratory of Molecular Biology in Medical Science of Zhejiang Province Cancer Institute the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

Objective:The purpose of this study was to determine the unique and universal features of microsatellite instability-high(MSI-H) colorectal cancer(CRC) and MSI-H gastric cancer(GC) in the Chinese ***:A new panel of mononucleotide MSI markers,BAT25,BAT26,NR21,NR24,and MONO-27,was used to define MSI status in 303 CRC and 288 GC *** features of both types of MSI-H tumors were *** analysis in the hMLH1 promoter region by methylation specific polymerase chain reaction(PCR) and mutation detection of hMSH2/hMLH1 genes by denaturing high-performance liquid chromatography(DHPLC) were carried out ***:MSI-H CRCs and MSI-H GCs account for 11.9% and 8.0% of unselected sporadic CRCs and GCs,***-H CRCs are strongly characterized by early onset,right-side location,low differentiation,mucinous tumor,less infiltration,less lymphatic metastasis,and more often familial ***-H GCs only showed site preference for the antrum and less lymphatic *** and epigenetic analyses were positive in 6/36 MSI-H CRCs and 0/23 MSI-H GCs with pathological mutation in major mismatch repair genes,and in 7/36 MSI-H CRCs and 18/23 MSI-H GCs with methylated hMLH1 promoter(P<0.01),***:Although there are many differences in the genetic basis and clinicopathological features between MSI-H CRC and MSI-H GC,when compared with their microsatellite stable(MSS) counterparts,site preference and lymphatic metastasis are features common to both types of MSI-H tumors.

关键词： Microsatellite instability Colorectal cancer Gastric cancer Mutation DNA methylation

Water leaching kinetics and recovery of potassium salt from sintering dust

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Transactions of Nonferrous Metals Society of China 2013年第12期23卷 3770-3779页

作者：詹光郭占成北京科技大学钢铁冶金新技术国家重点实验室北京100083

Surface morphology and inner structure of the dust were observed by ICP-AES, SEM-EDS and XRD to examine the strengthening measures of leaching potassium salt from the sintering dust by water. The results showed that the main component of the sintering dust was iron-oxygen compound, with KCl adsorbed on its surface. Leaching experiments showed that the KCl in the ESP dust could be separated and recovered by water leaching and fractional crystallization. The yield of K-Na vaporized crystalline salt was 18.56%, in which the mass fractions of KCl, NaCl, CaSO4 and K2SO4 were about 61.21%, 13.40%, 14.62%and 10.86%, respectively. The leaching kinetics of potassium salt from the sintering dust fits the external diffusion model well. The leaching speed and the leaching rate of the potassium salt can be increased by increasing the leaching temperature, strengthening the stirring speed and increasing the liquid-solid ratio.

关键词： potassium salt sintering dust leaching kinetics intensified leaching

Preparation of potassium salt with joint production of spherical calcium carbonate from sintering dust

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Transactions of Nonferrous Metals Society of China 2015年第2期25卷 628-639页

作者：詹光郭占成北京科技大学钢铁冶金新技术国家重点实验室北京100083

Several physical and chemical detection methods were used to study the basic properties of sintering dust （ESP dust） collected from Baogang Steel Corporation. The result shows that the major constituents of the ESP dust are KCl, NaCl, Fe2O_3 and Fe3O_4. Water leaching experiment on the sintering dust shows that KCl in the ESP dust can be separated and recovered by water leaching and fractional crystallization. Component analysis of leaching solution indicates that the massive calcium sulfate in the leaching solution should be removed first in order to obtain the pure potassium salt. In order to provide theoretical guidance to inhibit the dissolution of calcium ions from the sintering dust, the water leaching experiment of ESP dust and the dissolution behavior of CaSO_4 in the potassium chloride, sodium chloride, potassium sulfate and their mixed salt solution were studied. It is found that, a lower liquid-solid ratio should be chosen in the leaching process to inhibit the dissolution of calcium sulfate dehydrate. Using sodium carbonate solution as a precipitating agent, the influences of the concentration of sodium carbonate solution, reaction temperature, stirring speed and equilibrium time on the preparation of the spherical calcium carbonate were studied. Spherical calcium carbonate with good dispersing performance and grain size distribution in nanometer range of less than 10 μm was obtained. Furthermore, a potassium recovery process with joint production of spherical calcium carbonate was designed. This process is technically viable and considerable in economic benefit.

关键词： sintering dust potassium salt recovery experiment spherical CaCO_3