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An artificial neural network model of the landscape pattern in Shanghai metropolitan region,China

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Frontiers in Biology 2006年第4期1卷 463-469页

作者： zhang liquan ZHEN Yu State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China

To characterize the urbanization pattern quantitatively,a study on the mechanisms of the landscape pattern formation could facilitate the understanding on urban landscape patterns and processes,the ecological and socioeconomic consequences of urbanization,as well as the establishment of more effective strategies for landscape *** this study,we integrated a Geographic Information System(GIS)-based analysis on landscape pattern with an artificial neural network(ANN)to quantitatively characterize the urbanization pattern of the metropolitan area of Shanghai,China,and to establish an ANN model that could preferably simulate the responses of urban landscape pattern to the natural and socioeconomic factors such as residence area,road density,population density,urban development history and the Huangpu River as an element of economic *** results showed that the ANN model seems appropriate for studying the nonlinear relationship among the forcing factors of urbanization and the urban landscape patterns,which provided an effective and practical approach for further understanding the mechanisms of the landscape formation pattern and the reciprocal relationship between landscape spatial pattern and ecological process.

关键词： Shanghai urbanization landscape pattern artificial neural network(ANN) forcing mechanism

Photo-induced Birefringence of Azo-dye Based on Three-dimensional Opal Photonic Crystals

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Chemical Research in Chinese Universities 2016年第6期32卷 1063-1068页

作者： ZHONG Qiulin ZOU Lu WANG Yinghui SUI Ning LIU Qinghui zhang liquan zhang Hanzhuang Key Laboratory of Physics and Technology for Advanced Batteries Ministry of Education College of Physics Jilin University Changchun 130012 P. R. China

A series of three-dimensional opal photonic crystals based on the polymer was synthesized and applied inthe field of photo-induced birefringence. The data show that the photo-induced birefringence（PIB） of pure Sudan IIIfilm could be enhanced by increasing the thickness of azo films. When Sudan III was distributed on thethree-dimensional opal photonic crystals, the photo-induced birefringence process could be modulated. In addition,the data also exhibit that the PIB processes with different pumping polarization directions are sensitive to the role ofphotonic crystals. The results could be beneficial to further understanding the photo-induced birefringence and uti-lizing the photonic crystals.

关键词： Photonic crystal Photo-reduced birefringence Azo-dye

Spectral characteristics of plant communities from salt marshes:A case study from Chongming Dongtan,Yangtze estuary,China

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Frontiers of Environmental Science & Engineering 2008年第2期2卷 187-197页

作者： liquan zhang zhanguo GAO Richard ARMITAGE Martin KENT State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China Environment Monitoring Center of Ningbo Ningbo 315012China Research Institute for the Built and Human Environment School of Environment and Life ScienceUniversity of SalfordSalford M54WTUK School of Geography University of PlymouthPlymouth PL48AAUK

The spectral reflectance of recently formed salt marshes at the mouth of the Yangtze River,which are undergoing invasion by Spartina alterniflora,were assessed to determine the potential utility of remotely sensed data in assessing future invasion and changes in species *** a review of published research on remote sensing of salt marshes,53 locations along three transects were sampled for paired data on plant species composition and spectral reflectance using a FieldSpecTM Pro JR Field Portable *** data were processed concerning reflectance,and the averaged reflectance values for each sample were reanalysed to correspond to a 12-waveband bandset of the Compact Airborne Spectral *** spectral data were summarised using principal components analysis(PCA)and the relationships between the vegetation composition,and the PCA axes of spectral data were *** first PCA axis of the reflectance data showed a strong correlation with variability in near infrared reflectance and‘brightness’,while the second axis was correlated with visible reflectance and‘greenness’.Total vegetation cover,vegetation height,and mudflat cover were all significantly related to the first *** implications of this in terms of the ability of remote sensing to distinguish the various salt marsh species and in particular the invasive species *** were *** differences in species with various physiognomies could be recognised but problems occurred in separating early colonising *** from other species at that *** work using multi-seasonal hyperspectral data might assist in solving these problems.

关键词： Chongming Dongtan of China salt marsh vegetation spectroradiometer compact airborne spectral imager(CASI) canopy reflectance indirect ordination

Studying the charge carrier properties in CuInS_2 films via femtosecond transient absorption and nanosecond transient photocurrents

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Chinese Physics B 2019年第5期28卷 222-225页

作者： Mingrui Tan Qinghui Liu Ning Sui Zhihui Kang liquan zhang Hanzhuang zhang Wenquan Wang Qiang Zhou Yinghui Wang Femtosecond Laser Laboratory Key Laboratory of Physics and Technology for Advanced Batteries College of PhysicsJilin University State Key Laboratory of Superhard Materials College of Physics Jilin University

The carrier behavior in CuInS_2 thin films at femtosecond and microsecond time scales is discussed in detail. Transient absorption data suggests that the photo-generated carriers relax rapidly accompanied by a change in energy. The photogenerated charge carriers are extracted by a bias electric field E in the nanosecond transient photocurrent system. An applied E improves the efficiency of photon conversion to charge carriers and enhances the velocity of the extracted charge carriers. In addition, there exists a threshold of illumination intensity in the extraction process of charge carriers in the CuInS_2 thin film, above which carrier recombination occurs. The corresponding loss further increases with illumination intensity and the recombination rate is almost independent of E. Our results provide useful insights into the characteristics of carriers in the CuInS_2 thin film and are important for the operation of optoelectronic devices realized with these films.

关键词： semiconductor film carrier dynamics transient absorption transient photocurrent

Human infection with a further evolved avian H9N2 influenza A virus in Sichuan, China

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Science China(Life Sciences) 2018年第5期61卷 604-606页

作者： Jianan Xu Shuang Li Yong Yang Bing Liu Huiping Yang Tiansu Li Lin zhang Wei Li Xiaohu Luo liquan zhang Ming Pan Sichuan Provincial Center for Disease Prevention and Control Chengdu 610000 China Bazhong Prefecture Center for Disease Prevention and Control Bazhong 636000 China Central Hospital of Bazhong City Bazhong 636000 China

Dear Editor,Avian influenza A （H9N2） virus plays a crucial role in interspecies transmission between animals and humans due to its wide host range, adaptation in mammals and the diversified gene reassortments. Since... 详细信息

关键词：流行性感冒 H9N2 病毒四川感染中国鸟哺乳动物

Improved face recognition based on the fusion of PCA feature extraction and sparse representation

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Improved face recognition based on the fusion of PCA feature...

Effects of Microstructure on Quasi⁃Static Transverse Loading Behavior of 3D Circular Braided Composite Tubes

第30届中国控制与决策会议

作者： Jie Gao liquan zhang College of Electrical and Information Engineering Beijing University of Civil Engineering and Architecture

Sparse representation is a hot research topic in the field of biometrics in recent years. Even though the image has different expression and illumination, as well as occlusion, most of the algorithms still have good recognition effect. However, when the image contains illumination and facial expression changes, sparse classification method does not have good robustness. In this paper, we present a method that combination the PCA feature extraction method and sparse representation, which is a simple and effective face recognition algorithm. Based on the sparse concentration index, we propose the index threshold. When the concentration index is lower than the threshold value, we need to choose five training samples which corresponding to the minimum residuals, then construct a new training sample dictionary, and use the reconstructed dictionary to classify the test samples. This method strengthening the verification of abnormal test samples and optimizes the classification strategy. Comparing with the traditional SRC method, the simulation results show that the improved method is better than the SRC classification.

关键词： Face recognition Sparse representation PCA feature extraction Two stage classification strategy Facial expression Illumination

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Journal of Donghua University(English Edition) 2021年第5期38卷 392-397页

作者： ZHOU Haili LI Chao HAN Chenchen LIU Zhiyan ZHOU Feng zhang liquan Nanjing Fiberglass Research&Design Institute Nanjing 210000China

The effects of microstructure on quasi-static transverse loading behavior of 3D circular braided composite tubes were studied. Transverse loading tests were conducted. Transverse load-deflection curves were obtained to analyze the effects of braiding parameters including the braiding angle, the wall thickness, and the diameter on the transverse loading of 3D circular braided composite tubes. Breaking loads, moduli and strengths had also been used to describe the transverse loading behaviors. The failure morphologies were shown to reveal damage mechanisms. From the results, the increase in braiding angle, wall thickness and diameter increases the ability of anti-deformation and breaking load of braided tubes. The breaking load of specimen with a braiding angle of 45° is about 1.68 times that of specimen with a braiding angle of 15°. The breaking load of specimen with 4 layers of yarns is about 2.15 times that of specimen with 2 layers of yarns. The breaking load of the tube with a diameter of 25.5 mm is about 2.39 times that of the tube with a diameter of 20.5 mm.

关键词： 3D circular braided composite tube quasi⁃static transverse loading test braiding parameter failure morphology

Transgene inheritance and quality improvement by expressing novel HMW glutenin subunit (HMW-GS) genes in winter wheat

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Chinese Science Bulletin 2003年第8期48卷 771-776页

作者： zhang Xiaodong, LIANG Rongqi, CHEN Xqing, YANG Fengping & zhang liquan Beijing Agro-Biotechnology Research Center, Beijing Academy of Ag-ricultural & Forestry Science, Beijing 100089, China Correspondence should be addressed to zhang Xiaodong (e-mail: zhangxd@***) Beijing Agro-Biotechnology Research Center Beijing Academy of Agricultural & Forestry Science Beijing China

The expression vector pBPC30, which carries the high molecular weight glutenin subunit (HMW-GS) 1Dx5 and 1Dy10 genes, was transferred into hexaploid winter wheat cv. Jinghua No. 1, Jing411 and Jingdong No. 6 ex-plants of immature embryos and immature inflorescence by particle bombardment. A large number of resistant trans-genic plants were obtained under the selection of herbicide bialaphos or phosphinothricin (PPT). Confirmed transgenic plants of T0 generation showed successful integration of HMW-GS genes and bar gene into the wheat genome. T1 generation of transgenic plants can resist 20150 mg/L PPT. Protein analysis of T2 seed by SDS-PAGE showed that HMW-GS 1Dx5 and 1Dy10 genes were well expressed in offspring seed of transgenic lines by co-expression with or substitution of endogenous 1Dx2 or 1Dy10. In one transgenic line, TG3-74, a new protein band between endogenous pro-tein subunits 7 and 8 (marked as 8*) of glutenin appeared, but endogenous subunit 8 (encoded by 1By8 gene) was ab-sent. Analysis of gluten rheological quality on seed proteins of 102 T3 plants showed that the sedimentation value of 5 transgenic lines (44.249.0 mL) was remarkably improved, 59.6%64.3% higher than that of wild type Jinghua No. 1 and Jingdong No. 6, similar to bread wheat Cheyenne (48.0 mL). Analysis of dough rheological properties of transgenic lines showed that the dough stable time of 5 transgenic lines range from 16 to 30 min, whereas the dough stable time of wild type was only between 37 min. Our research suggests that introducing novel HMW-GS genes into wheat is an effi-cient way to improve its bread-making quality.

关键词：转基因技术麦谷蛋白冬小麦基因表达

土壤生物工程在河道坡岸生态修复中应用与效果

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应用生态学报 2006年第9期17卷 1705-1710页

作者：李小平张利权上海市环境科学研究院上海200233 华东师范大学河口海岸国家重点实验室上海200062

土壤生物工程是一项采用存活植物构筑边坡结构,稳定河道(流)坡岸和生态修复的工程技术.本文简要讨论了土壤生物工程的原理和活枝扦插、柴笼、灌丛垫以及复合工程等基本种植技术;介绍了我国第一个采用土壤生物工程修复河道坡岸的示范工程... 详细信息

土壤生物工程是一项采用存活植物构筑边坡结构,稳定河道(流)坡岸和生态修复的工程技术.本文简要讨论了土壤生物工程的原理和活枝扦插、柴笼、灌丛垫以及复合工程等基本种植技术;介绍了我国第一个采用土壤生物工程修复河道坡岸的示范工程,对比了工程实施后河道坡岸10个月来的坡岸土壤剪切力、生境条件和生物多样性变化.研究和示范工程表明,采用土壤生物工程方法可以稳定坡岸、改善坡岸的栖息地质量、修复河道的生态环境.土壤生物工程方法可以在我国各类岸(边)坡的生态修复中广泛运用.

关键词：土壤生物工程河道坡岸生态修复