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Categories and characteristics of urban villages by GIS-based analysis:A case study of the Shenzhen Special Economic Zone

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science{1.(Technological sciences) 2010年第S1期53卷 150-157页

作者： TONG De1.FENG ChangChun2,LI GuiCai1.& CHEN peng1.2 1. henzhen Graduate {1.,Peking university,Shenzhen 51.055,china 2College of Urban and Environmental science,Peking university,Beijing 1.0871.china 1. Shenzhen Graduate school Peking University Shenzhen 518055 China 2. College of Urban and Environmental science Peking University Beijing 100871 China

Studies on the characteristics of urban villages have attracted much interest in urban ***,how to advance the development of further theoretical analysis and quantitative methodologies,especially in the era that GIS and digital-urban technologies develop rapidly and provide precious resources on spatial issues,has always been a heated debate and *** this paper,a mathematical model based on spatial analysis is introduced to deal with the categorization and characterization of urban villages.A total of 89 urban villages in the Shenzhen Special Economic Zone(SEZ)are used in this case *** ArcGIS tools on buffer analysis,distance and density calculation,and socio-economic and spatial attributes conjunction,urban villages’31.spatial variables in 4 aspects—social,economic,locational,and physical—are extracted,and 6 principal factors are concluded by principal components analysis to indicate the spatial characteristic of urban *** on the 6 principal factors,6 types of urban villages,including rapidly sprawling,large,rapidly industrializing periphery,overcrowded,intensively mobile and economically backward,are divided through the Hierarchical Clustering ***,the spatial features and formation mechanisms of each type of urban villages are ***,the advantages and the shortcomings of the methodology for this specific application are also ***,several guidelines on urban village management and renewal are provided based on the result of type *** outcome of the paper depends on the informational and technological support from the development of digital-city management,and is able to in turn provide basis on monitoring and improving urban villages which can further digital urban framework.

关键词： urban villages GIS-based analysis principal component hierarchical cluster the Shenzhen Special Economic Zone (SEZ)

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Identification of Motor Nuclei in the Medulla Oblongata of Carp for Biological Control

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Journal of Bionic Engineering 2024年第2期21卷 842-851页

作者： Yang zhao Yong {1. Yudong Wen Lingjun Han Yanhong Yan Xueying Dong Hui Zhang Zheng zhao Xiaoyue liu school of Electrical Engineering Yanshan UniversityQinhuangdao066004China school of Mechanical Engineering Yanshan UniversityQinhuangdao066004China Key Laboratory of National Defense of Mechanical Structure and Material science Under Extreme Conditions Yanshan UniversityQinhuangdao066004China Institute of Marine science and Engineering Yanshan UniversityQinhuangdao066004China Shijiazhuang university Shijiazhuang050035China

Brain-controlled technology is the key technology in biological control,and the corresponding relationship between animal brain nuclei and motor behavior is the *** purpose of this study was to explore the motor nuclei of the medulla oblongata in *** carps were subjected to electrical stimulation and chemical stimulation experiments,respectively,in the water-free state,and the effective chemical stimulation sites were injected with the pontamine sky blue *** brain tissue sections were obtained by paraffin tissue section technology and the neutral red staining *** comparing the positions of the brain nuclei shown in earlier studies,the motor nerve nuclei in the medulla oblongata were *** brain electrode was implanted into the motor nucleus of the medulla oblongata,and the underwater control experiment and behavioral tests were carried out with different electrical stimulation *** results showed that the abducens nucleus(NVI)was the motor nucleus that controls the ipsilateral steering,and the facial nucleus(NVII)was the motor nucleus that controls the forward *** adjusting the stimulation voltage and the stimulation pulse number,the carp can be stably controlled to achieve a left–right steering motion of 30°–1.0°and a forward motion of more than 80 cm/*** study indicated that the quantitative control of the steering and forward behavior of the carp can be achieved by electrical stimulation of the NVI and NVII,which provided a certain experimental basis for the accurate control of the carp robot.

关键词： Biological control Carp Medulla oblongata motor nucleus Electrical stimulation technique Chemical stimulation technique

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Swelling of Spherical Polyelectrolyte Gels

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Chinese Journal of Polymer science 2024年第9期42卷 1386-1392,I0009页

作者： Ming-Yu Duan Jia-Dong Chen Yi-Ming liu {1.-Feng peng Guang Chen Department of Advanced Manufacturing and Robotics College of EngineeringPeking UniversityBeijing 100871China

Polyelectrolyte(PE)gels,distinguished by their unique stimuli-responsive swelling behavior,serve as the basis of broad applications,such as artificial muscles and drug *** this work,we present a theoretical model to analyze the electrostatics and its contribution to the swelling behavior of PE gels in salt *** minimizing the free energy of PE gels,we obtain two distinct scaling regimes for the swelling ratio at equilibrium with respect to the salt *** compare our predictions for the swelling ratio with experimental measurements,which show excellent *** addition,we employ a finite element method to assess the applicability range of our theoretical model and *** anticipate that our model will also provide valuable insights into drug adsorption and release,deformation of red blood cells,4D printing and soft robotics,where the underlying mechanism of swelling remains enigmatic.

关键词： Gels Polyelectrolytes Swelling Stimuli-responsive Electrostatic interaction Cell model

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Synthesis and photochromic properties of WO_3 powder induced by oxalic acid

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science{1. Chemistry 2009年第5期52卷 609-614页

作者： SHEN Yi1. ZHU Hua1. HUANG Rong1. zhao Li2 & YAN ShaNing1.1.Faculty of Material {1. and Chemical Engineering, china university of Geo{1.s, Wuhan 430074, china 2 Faculty of Materials {1. and Engineering, Hubei university, Wuhan 430062, china 1. Faculty of Material science and Chemical Engineering China University of Geosciences Wuhan 430074 China 2. Faculty of Materials science and Engineering Hubei University Wuhan 430062 China

Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up of regularly spindle particles with 200-300 nm in length and 30-50 nm in width. The ratio of the length and width was from 4 to 1.. Moreover, the special morphology improved its absorptive capacity to the excitation light source, resulting in its high photochromic properties.

关键词： WO3 powder photochromism oxalic acid organic inducer

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Balanced multiple description subband coding based on multifilter banks

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science{1.(Information sciences) 2011年第11期54卷 2359-2372页

作者： WANG Ning 1.LI BaoBin 2 & peng LiZhong 1.1.LMAM,{1. of Mathematical sciences,Peking university,Beijing 1.0871.china 2 {1. of Information science and Engineering,Graduate university of Chinese Academy of sciences,Beijing 1.01.0,china 1. LMAM School of Mathematical Sciences Peking University Beijing 100871 China2. School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing 100190 China

Multiple description coding is one of the source coding techniques to alleviate the problems of packet loss in *** encoder generates several different descriptions of the source and the decoder can produce a useful reconstruction with any received subset of these *** of the earlier works concentrated on redundancy and the average distortion of the single-description reconstructions,which is insufficient to describe the *** this paper,a metric of the coding system,balance eccentric modulus,is defined to evaluate the difference in quality between the individual *** the discrete wavelet transform becomes trivial polyphase transform when setting the balance eccentric modulus at zero,we introduce a multiwavelet based scheme ***,a sufficient condition for balanced multiwavelet based multiple description coding is presented.

关键词： multiple description coding rate-distortion theory balance eccentric modulus balanced multiwavelet multifilter bank

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Hydration Kinetics of Phosphorus Slag-cement Paste

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Journal of Wuhan university of Technology(Materials {1.) 2011年第1期26卷 142-146页

作者：陈霞 school of Civil Engineering Wuhan University Department of Mateials and Structure Changjiang River Scientific Research lnstitute

Hydration characteristics of Portland cement paste with phosphorus slag powder incorporated and hydration kinetics was investigated with SEM, X-ray diffraction, DTA-TG and calorimeter Ⅱ80. Results showed that phosphorus slag powder could reduce total amount of hydration products yet had little influence on the type of hydration products. The total amount of heat of hydration was decreased by 49.1.% and the final setting was postponed by 2.28 h when phosphorus slag powder substituted 35% Portland cement by mass. The accelerating stage of this composite paste was controlled by catalysis, decreasing stage controlled by both catalysis and diffusion while stabilizing stage by diffusion alone. Hydration resistance and activation energy were reduced and hydration speed was accelerated.

关键词： phosphorus slag hydration kinetics cement micro structure mechanism.

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Radiance-based color calibration for image-based modeling with multiple cameras

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science{1.(Information sciences) 2012年第7期55卷 1509-1519页

作者： zhao Xu 1.2 ,ZHOU Zhong 1.2 & WU Wei 1.2 1.State Key Laboratory of Virtual Reality Technology and Systems,Beihang {1.,Beijing 1.01.1.china 2 school of Computer science and Engineering,Beihang {1.,Beijing 1.01.1.china 1. State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China2. School of Computer Science and Engineering Beihang University Beijing 100191 China

Photo-consistency estimation is an important part for many image-based modeling *** paper presents a novel radiance-based color calibration method to reduce the uncertainty of photo-consistency estimation across multiple *** idea behind our method is to convert colors into a uniform radiometric color space in which multiple image data are *** results demonstrate that our method can achieve comparable color calibration effect without adjusting camera parameters and is more robust than other existing ***,we obtain an auto-determined threshold for photo-consistency check,which will lead to a better performance than existing photo-consistency based reconstruction algorithms.

关键词： color calibration photo-consistency estimation multi-camera system image-based modeling

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Non-invasive scanning ion-selective electrode technique and its applications to the research of higher plants

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Progress in Natural science:Materials International 2007年第6期17卷 625-629页

作者： Sun Tong1. Xu Yue2, Li peng1. Yu Shangguan2 and Yin Liping1.1. College of Life {1., Capital Normal university, Beijing 1.0037, china 2. Younger USA {1. & Technology Corporation, 7 Dayton Lane, Amherst MA 01.02, USA) [a]College of Life science Capital Normal University Beijing China [b]Younger USA science & Technology Corporation Amherst MA USA

The process of various ions and molecules getting into and out of cells is critical for plant survival. The non-invasive scanning ion-selective electrode technique (SIET) is a non-invasive method to obtain the information of ions/molecules across membranes in plant. This technique can measure the absolute concentration of ions and molecules, and also their fluxes and directions of movement. The samples to be analyzed can be a single cell, a piece of tissue, a whole organ and even an intact seedling. This article reviews the recent progress made in plant physiology by using this technique and discusses its potentials in future studies on plant physiology.

关键词： non-invasive electrophysiology technique ion-selective electrode ion transport across membrane SIET.

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Ferroelectric properties of Bi_4Zr_(0.5)Ti_(2.5)O_(1.) thin films prepared on LaNiO_3 bottom electrode by sol-gel method

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science{1.(Technological sciences) 2007年第4期50卷 472-477页

作者： GUO DongYun1. LI MeiYa1. liu Jun1. PEI Ling1. YU BenFang1. {1. XingZhong1. YANG Bin2, WANG YunBo2 & YU Jun2 1.Department of Physics, Wuhan university, Wuhan 430072, china 2 Department of Electronic science and Technology, Huazhong university of science and Technology, Wuhan 430074, china 1. Department of Physics Wuhan University Wuhan 430072 China 2. Department of Electronic science and Technology Huazhong University of Science and Technology Wuhan 430074 China

The Bi4Zr0.5Ti2.5O1. (BZT) thin films were fabricated on the LaNiO3 bottom electrode using sol-gel method. The structure and morphology of the films were character-ized using X-ray diffraction, AFM and SEM. The results show that the films have a perovskite phase and dense microstructure. The 2Pr and 2Vc of the Pt/BZT/LaNiO3 capacitor are 28.2 μC/cm2 and 1..7 V respectively at an applied voltage of 25 V. After the switching of 1.1.1. cycles, the Pr value decreases to 87% of its pre-fatigue val-ues. The dielectric constant (ε) and the dissipation factor (tanδ) of the BZT thin films are about 204 and 0.029 at 1.kHz, respectively. The films show good insulating behavior according to the test of leakage current. The clockwise C-V hysteresis curve observed shows that the Pt/BZT/LaNiO3 structure has a memory effect be-cause of the BZT film’s ferroelectric polarization.

关键词： Bi_4Zr_(0.5)Ti_(2.5)O_(1.) thin film sol-gel method LaNiO_3 bottom electrode ferroelectric properties

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Pyridapeptides F–I,cyclohexapeptides from marine sponge-derived Streptomyces ***-4539

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Chinese Chemical Letters 2024年第7期35卷 341-344页

作者： Shuige zhao {1.cheng Yan Peipei liu Haishan liu Ning Li {1. Fu Weiming Zhu Key Laboratory of Marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Key Laboratory for Marine Drugs and Bioproducts Laoshan LaboratoryQingdao 266237China school of Biological {1. and Technology University of JinanJi'nan 250022China Key Laboratory for Biosensors of Shandong Province Biology InstituteQilu University of TechnologyJi'nan 250103China

Four new cyclohexapeptides,pyridapeptides F–I(1.4),were isolated from the fermentation broth of marine sponge-derived Streptomyces *** pyridapeptides F–H(1.3)are composed ofβ-hydroxyleucine,alanine,O-methylthreonine,hexahydropyridazine-3-carboxylic acid,5-hydroxytetrahydropyridazine-3-carboxylic acid,and(2S,3R,4E,6E)-2-amino-3–hydroxy-4,6-dienoic acid *** I(4)contains(2S,3R,4E,6E)-2-amino-3–hydroxy-8-methylnona-4,6-dienoic acid residue and a very rare glycose residue,*** structures were determined based on spectroscopic analysis and chemical *** G–I(2–4)have the 2,3,6-trideoxyhexose units glycosylated at theγ-OH-TPDA residue,displayed significant antiproliferative activity against four(PC9,MKN45,Hep G2,K562)or two(PC9,MKN45)human cancer cell lines.

关键词： Marine microorganism Streptomyces Cyclopeptide glycosides Pyridapeptides Antiproliferative activity

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