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Research on polarization of oil spill and detection

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Acta Oceanologica Sinica 2016年第3期35卷 84-89页

作者： CAI Yang zou Yarong LIANG Chao zou bin South China Sea Forecast Center State Oceanic Administration Guangzhou 510310 China National Satellite Ocean Application Services Beijing 100081 China Key Laboratory of Space Ocean Remote Sensing and Application State Oceamic Administration Beijing 100081 China

The SAR（Synthetic Aperture Radar） has the capabilities for all-weather day and night use. In the case of determining the effects of oil spill dumping, the oil spills areas are shown as dark spots in the SAR ***, using SAR data to detect oil spills is becoming progressively popular in operational monitoring, which is useful for oceanic environmental protection and hazard reduction. Research has been conducted on the polarization decomposition and scattering characteristics of oil spills from a scattering matrix using allpolarization of the SAR data, calculation of the polarization parameters, and utilization of the CPD（Co-polarized Phase Difference） of the oil and the sea, in order to extract the oil spill information. This method proves to be effective by combining polarization parameters with the characteristics of oil spill. The results show that when using Bragg, the oil spill backscattering machine with Enopy and a mean scatter α parameter. The oil spill can be successfully identified. However, the parameter mechanism of the oil spill remains unclear. The use of CPD can easily extract oil spill information from the ocean, and the polarization research provides a base for oil spill remote sensing detection.

关键词： oil spill polarization detection SAR

Spatiotemporal influences of land use/cover changes on the heat island effect in rapid urbanization area

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Frontiers of Earth Science 2019年第3期13卷 614-627页

作者： Ying XIONG Fen PENG bin zou Research Center of Resource Environment and Urban Planning Changsha 410114China School of Architecture Changsha University of Science & TechnologyChangsha 410114China School of Geosciences and Info-physics Central South UniversityChangsha 410083China

Rapid urban sprawl and growth led to substantial urban thermal environment changes and influenced the local climate, environment, and quality of life of residents. Taking the Chang-Zhu-Tan urban agglomeration in China as a case, this study firstly identified the spatiotemporal patterns of surface urban heat island intensity (SUHII) and the land use/cover changes (LUCC) based on multi-temporal Landsat TM satellite data over 21 years, and then investigated the relationship between LUCC and SUHII by methods of logistic regression model and centroid shift analysis. The results showed that green spaces (e.g., cropland, forestland) of 899.13 km2 had been converted to built-up land during the 1994—2015 period, which caused significant urban expansion. The SUHII was the highest for built-up land, high for unused land, low for cropland and grassland, and the lowest for forestland and open water. Many areas experienced extensive rapid urbanization because of the emergence of the urban agglomeration, which resulted in the loss of green spaces and increased SUHI effects over the 21-year study period. In addition, the results of centroid shift analysis found that the growth of SUHII and the expansion of high SUHII areas are closely related to the expansion of an existing urban area in Xiangtan, while the increases of building density and height in Changsha resulted in the decrease of SUHII and spatiotemporal change of high SUHII areas. The analysis of the effects of land use/cover types on the SUHII in this study will contribute to future urban land use allocation for the mitigation of SUHI formation.

关键词： land use/cover change urbanization remote sensing surface urban heat island intensity centroid shift analysis

Self-organizing dual clustering considering spatial analysis and hybrid distance measures

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Science China Earth Sciences 2011年第8期54卷 1268-1278页

作者： JIAO LiMin LIU YaoLin zou bin School of Resource and Environment Science Wuhan University Wuhan 430079 China Key Laboratory of Geographic Information System Ministry of Education Wuhan University Wuhan 430079 China School oflnfo-physics and Geomatics Engineering Central South University Changsha 410086 China

Dual clustering performs object clustering in both spatial and non-spatial domains that cannot be dealt with well by traditional clustering ***,recent dual clustering research has often omitted spatial outliers,subjectively determined the weights of hybrid distance measures,and produced diverse clustering *** this study,we first redefined the dual clustering problem and related concepts to highlight the clustering *** then presented a self-organizing dual clustering algorithm (SDC) based on the self-organizing feature map and certain spatial analysis operations,including the Voronoi diagram and polygon aggregation and *** algorithm employs a hybrid distance measure that combines geometric distance and non-spatial similarity,while the clustering spectrum analysis helps to determine the weight of non-spatial similarity in the measure.A case study was conducted on a spatial database of urban land price samples in Wuhan,*** detected spatial outliers and clustered the points into spatially connective and attributively homogenous *** particular,SDC revealed zonal areas that describe the actual distribution of land prices but were not demonstrated by other *** reduced the subjectivity in dual clustering.

关键词： dual clustering datamining self-organizing feature map Voronoi diagram

The learning performance of support vector machine classification based on Markov sampling

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Science China(Information Sciences) 2013年第3期56卷 107-122页

作者： zou bin PENG ZhiMing XU ZongBen Faculty of Mathematics and Computer Science Hubei University Institute for Information and System Science Xi'an Jiaotong University

The previously known frameworks describing the consistency of support vector machine classification(SVMC) algorithm are usually based on the assumption of independent and identically distributed(i.i.d.) *** this paper we go far beyond these classical frameworks by studying the consistency of SVMC algorithm with uniformly ergodic Markov chain samples based on linear prediction *** establish the bound on the consistency of SVMC algorithm with uniformly ergodic Markov chain samples,and show that SVMC algorithm with uniformly ergodic Markov chain samples is *** by the idea from Markov chain Monto Carlo(MCMC) methods,we introduce a new Markov sampling algorithm for classification to generate uniformly ergodic Markov chain samples from large data set,and present numerical studies on simulated data and benchmark repository using SVMC algorithm.

关键词： SVMC uniformly ergodic Markov chain learning performance Markov sampling linear prediction models

A routine operational backscattering coefficient regrouping algorithm for a HY-2A scatterometer

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Acta Oceanologica Sinica 2018年第3期37卷 111-116页

作者： zou Juhong LIN Mingsen zou bin GUO Maohua ZHANG Yi Key Laboratory of Space Ocean Remote Sensing and Application State Oceanic Administration National Satellite Ocean Application Sevice State Oceanic Administration

The routine operational sigma0 regrouping method is proposed for a HY-2 A scatterometer（HSCAT） that maps time-ordered sigma0 s and related parameters into a subtrack aligned grid of wind vector cells（WVCs）. The regrouping method consists of two critical steps： ground grid generation and sigma0 resampling. The HSCAT uses subtrack swath coordinates, in which the nadir track of the satellite represents the center and the designated positions are specified in terms of a pair of along-track and cross-track coordinates. To calculate the subtrack coordinates for each sigma0, a ＂triangle marking＂ resampling method is developed. Three points, including the point of intersection, the center of a pulse footprint, and the origin of the subtrack coordinate system, form a right triangle; the length of the two right-angled sides is used to represent the cross-track and the along-track coordinates in the subtrack coordinate system. In addition, a nadir point interpolation correction is used to ensure the operation of the regrouping algorithm when the nadir point positional information is missing. To illustrate the ability of the proposed regrouping algorithm, the distribution of the WVC positions and wind vector retrieval results are analyzed, which show that the proposed regrouping algorithm meets the requirements for high-quality sea surface wind field retrieval.

关键词： regrouping HY-2A scatterometer backscattering coefficient

Synergistically Toughening Effect of SiC Whiskers and Nanoparticles in Al_2O_3-based Composite Ceramic Cutting Tool Material

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 977-982页

作者： LIU Xuefei LIU Hanlian HUANG Chuanzhen WANG Limei zou bin ZHAO bin Centre for Advanced Jet Engineering Technologies School of Mechanical EngineeringShandong University School of Mechanical and Electrical Engineering Qilu Institute of Technolegy Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education Shandong University

In recent decades, many additives with different characteristics have been applied to strengthen and toughen Al2O3-based ceramic cutting tool materials. Among them, SiC whiskers and SiC nanoparticles showed excellent performance in improving the material properties. While no attempts have been made to add SiC whiskers and SiC nanoparticles together into the ceramic matrix and the synergistically toughening effects of them have not been studied. An Al2O3-SiCw-SiC np advanced ceramic cutting tool material is fabricated by adding both one-dimensional SiC whiskers and zero-dimensional SiC nanoparticles into the Al2O3 matrix with an effective dispersing and mixing process. The composites with 25 vol% SiC whiskers and 25 vol% SiC nanoparticles alone are also investegated for comparison purposes. Results show that the Al2O3-SiCw-SiCnp composite with both 20 vo1% SiC whiskers and 5 vol% SiC nanoparticles additives have much improved mechanical properties. The flexural strength of Al2O3-SiCw-SiCnp is 730＋ 95 MPa and fracture toughness is 5.6 ± 0.6 MPa.m1/2. The toughening and strengthening mechanisms of SiC whiskers and nanoparticles are studied when they are added either individually or in combination. It is indicated that when SiC whiskers and nanoparticles are added together, the grains are further refined and homogenized, so that the microstructure and fracture mode ratio is modified. The SiC nanoparticles are found helpful to enhance the toughening effects of the SiC whiskers. The proposed research helps to enrich the types of ceramic cutting tool and is benefit to expand the application range of ceramic cutting tool.

关键词： Al2O3-based ceramic cutting tool materials SiC whiskers SiC nanoparticles mechanical properties,toughening and strengthening mechanisms

Reducing environmental risk of nitrogen by popularizing mechanically dense transplanting for rice production in China

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Journal of Integrative Agriculture 2020年第9期19卷 2362-2366页

作者： HUANG Min zou Ying-bin Crop and Environment Research Center College of AgronomyHunan Agricultural UniversityChangsha 410128P.R.China

The high nitrogen(N)application rates typically used in Chinese cropping systems have led to diminishing returns for yields and have also imposed substantial environmental ***,we estimate that the annual N loss from rice production in China reached approximately 2.6×109 kg from 2011 to 2015,and we demonstrate that adoption of the mechanically dense transplanting technique by producers is an effective method to reduce N loss from rice cropping systems without suffering a yield penalty.

关键词： dense planting environmental risk mechanical transplanting nitrogen loss rice

Entropy Exchange and Entanglement in Superconducting Charge Qubit Inside a Resonant Cavity with Intrinsic Decoherence

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Communications in Theoretical Physics 2008年第6期49卷 1463-1467页

作者： ZHANG Jian SHAO bin zou Jian Department of Physics Beijing Institute of Technology Beijing 100081 China

By considering the intrinsic decoherence effect, we investigate the entropy exchange and entanglement in the interacting system of a superconducting charge qubit coupled to a single-mode optical cavity. We found that although the intrinsic decoherence leads to an irreversible evolution of the interacting system due to a suppression of coherent quantum features through the decay of off-diagonal matrix elements of the density operator, and has an apparently influence on the partial entropies of the two-component subsystems, it dose not destroy entropy exchange behavior. In addition, the lower bound of the concurrence, as the measure of entanglement of the coupling system, is calculated. It is shown that the evolution of entanglement is sensitive to the change of the intrinsic decoherence.

关键词： intrinsic decoherence entropy exchange entanglement the lower bound of concurrence

Quantum Information Processing in a Coupled Cavity Array

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Communications in Theoretical Physics 2008年第12期50卷 1312-1316页

作者： LI Jian zou Jian SHAO bin Department of Physics Beijing Institute of Technology Beijing 100（}81 China

We consider a one-dimensional array of L identical coupled cavities,and each cavity is doped with atwo-level ***,it has been developed in several varieties by the newest *** find that theone-qubit quantum state can be perfectly transferred through the cavity array,and the entanglement between the firsttwo qubits can also be transferred to the last two *** addition,we successfully realized the entangling gate andswap gate in the coupled cavity array.

关键词： state transfer entanglement transfer quantum gate coupled cavity array