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Winter wheat identification by integrating spectral and temporal information derived from multi-resolution remote sensing data

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Journal of Integrative Agriculture 2019年第11期18卷 2628-2643页

作者： ZHANG Xi-wang LIU jian-feng Zhenyue Qin QIN fen Key Laboratory of Geospatial Technology for Middle and Lower Yellow River Regions Ministry of EducationKaifeng 475004P.R.China Research School of Computer Science The Australian National UniversityCanberra 2601Australia College of Environment and Planning Henan UniversityKaifeng 475004P.R.China Yellow River Conservancy Technical Institute Kaifeng 475004P.R.China Institute of Urban Big Data Henan UniversityKaifeng 475004P.R.China

Timely crop acreage and distribution information are the basic data which drive many agriculture related *** identifying crop types based on remote sensing,methods using only a single image type have significant *** research that integrates fine and coarser spatial resolution images,using techniques such as unmixing methods,regression models,and others,usually results in coarse resolution abundance without sufficient detail within pixels,and limited attention has been paid to the spatial relationship between the pixels from these two kinds of *** we propose a new solution to identify winter wheat by integrating spectral and temporal information derived from multi-resolution remote sensing data and determine the spatial distribution of sub-pixels within the coarse resolution ***,the membership of pixels which belong to winter wheat is calculated using a 25-m resolution resampled Landsat Thematic Mapper(TM)image based on the Bayesian ***,the winter wheat abundance(acreage fraction in a pixel)is assessed by using a multiple regression model based on the unique temporal change features from moderate resolution imaging spectroradiometer(MODIS)time series ***,winter wheat is identified by the proposed Abundance-Membership(AM)model based on the spatial relationship between the two types of ***,winter wheat is identified by comparing the spatially corresponding 10×10 membership pixels of each abundance *** other words,this method takes advantage of the relative size of membership in a local space,rather than the absolute size in the entire study *** method is tested in the major agricultural area of Yiluo Basin,China,and the results show that acreage accuracy(Aa)is 93.01%and sampling accuracy(As)is 91.40%.Confusion matrix shows that overall accuracy(OA)is 91.4%and the kappa coefficient(Kappa)is *** values are significantly improved compared to the traditional Maximum Likeli

关键词： temporal change characteristics membership abundance winter wheat multi-resolution remote sensing

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Analysis of the Abnormal Segregation of Pathogenicity in Magnaporthe grisea by Using a Genetic Cross of Oryza and Eleusine Isolates

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Agricultural Sciences in China 2010年第3期9卷 383-391页

作者： YIN liang-fen LUO Chao-xi Kusaba Motoaki Yaegashi Hiroshi Department of Plant Pathology College of Plant Science and Technology Huazhong Agricultural University Wuhan 430070 P.R.China Key Lab of Crop Disease Monitoring ＆ Safety Control in Hubei Province Huazhong Agricultural University Wuhan 430070 P.R.China Faculty of Agriculture Saga University Saga 840-8502 Japan

A genetic cross between Oryza isolate Y93-164a-1 and Eleusine isolate SA98-4 was established, and the pathogenicity of 151 F1 progeny isolates was investigated on both host plants rice and finger millet. Results showed that the segregation of pathogenicity in this genetic cross was abnormal, i.e., most of the progeny isolates were nonpathogenic on both host plants. However, no abnormal segregation was observed when middle repetitive sequence MGR586 and 31 single-copy RFLP markers from all of the chromosomes were genetically analyzed. At the same time, comparison of the chromosomal organization among two pairs of parental isolates did not find any genomic abnormity. These results suggested that the ＂abnormal＂ inheritance of pathogenicity in this cross was most likely due to the reassortment of numerous host species specificity genes but not the biased segregation of the host species specificity genes. The host species specificities in M. grisea were likely to be multigenically controlled, at least in the genetic cross involving rice pathogen and the grasses pathogen other than rice.

关键词： Magnaporthe grisea rice blast fungus host species specificity pathogenicity contour-clamped homogeneous electric field (CHEF) electrophoresis Southern hybridization

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Heat transport mechanisms of low Mach number turbulent channel flow with spanwise wall oscillation

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Acta Mechanica Sinica 2010年第3期26卷 391-399页

作者： jian Fang Li-Peng Lu liang Shao National Key Laboratory of Science and Technology on Aero-Engines School of Jet Propulsion Beihang University 100191 Beijing China Laboratory of Fluid Mechanics and Acoustics Ecole Centrale de Lyon Lyon France

Large eddy simulation （LES） of low Mach num- ber compressible turbulent channel flow with spanwise wall oscillation （SWO） is carried out. The flow field is analyzed with emphases laid on the heat transport as well as its rela- tion with momentum transport. When turbulent coherent structures are suppressed by SWO, the turbulent transports are significantly changed, however the momentum and heat transports change in the same manner, which gives the evi- dence of inherently consistent transport mechanisms between momentum and heat in turbulent boundary layers. The Reynolds analogies of all the flow cases are quite good, which confirms again the fact that the transport mechanisms of momentum and heat are consistent, which gives theoreti- cal support for controlling the wall heat flux control by using the drag reducing techniques.

关键词： Large eddy simulation Turbulent heat transport Wall heat fluxSpanwise wall oscillation

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Design Strategy of Infrared 4-Hydroxybenzylidene-imidazolinone-Type Chromophores based on Intramolecular Charge Transfer:a Theoretical Perspective

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Chinese Journal of Chemical Physics 2023年第5期36卷 582-592,I0002页

作者： jian Song WenLong liang Shouning Yang Huayan Yang School of Physics Henan Normal UniversityXinxiang 453007China NMPA Key Laboratory for Research and Evaluation of Innovative Drug Henan Key Laboratory of Organic Functional Molecule and Drug InnovationCollaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China

Partial genetically encoded 4-hy-droxybenzylidene-imidazolinone(HBI)-type chromophores are new promising fluorescent probes,which are suitable for imaging and detection of living ***-ever,the lack of infrared chro-mophores hinders the develop-ment *** more than 30 HBI-type chromophores with reg-ular structure modifications were employed and typical spectral redshift change laws and mechanisms were investigated by quantum *** show that both one-photon spectrum(OPS,absorption/emission)and two-photon absorption(TPA)can achieve large redshift via either extending conjugated lengths of frag-3 or enlarging conjugated areas of frag-1 of HBI *** redshifts of all chromophores are highly related to intramolecular charge transfer(ICT),but neutral ones are closely related to the total ICT or electron-accept-ing-numbers of frag-3,and the high correlative factor of anions is the aromaticity of frag-2 *** frag-2 bridge with high aromaticity can open a reverse charge transfer channel in anion relative to neutral,obtaining significant *** on analysis,a new 6-hydroxyl-naphthalene-imidazolinone(HNI)series,which have larger conjugated area in frag-1,are *** OPS and TPA of anionic HNI ones acquire about 76−96 nm and 119−146 nm red-shift relative to traditional HBI series respectively as a *** longest emission of anionic HNI-4 realizes more 244 nm redshift relative to *** work clarifies worthy spectral reg-ularities and redshift mechanisms of HBI-type chromophores and provides valuable design strategy for infrared chromophores synthesis in experiment.

关键词： Intramolecular charge transfer Near-infrared fluorescent chromophore 4-Hy-droxybenzylidene-imidazolinone One-photon spectrum Two-photon absorption

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Securing offshore resources development:A mathematical investigation into gas leakage in long-distance flexible pipes

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Petroleum Science 2024年第4期21卷 2734-2744页

作者： Xiang-An Lu liang-liang jiang jian-Sheng Zhang Min-Gui Wang Guangling College of Yangzhou University Yangzhou225131JiangsuChina Department of Chemical and Petroleum Engineering University of CalgaryCalgaryT2N 1N4AlbertaCanada Department of Energy and Power Engineering Tsinghua UniversityBeijing100084China

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas *** high pressure conditions,small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space,incurring annular pressure build-up and/or production of acidic environment,which poses serious challenges to the structure and integrity of the flexible *** permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature,annular structure,external *** a long-distance gas flexible pipe,moreover,gas permeation exhibits non-uniform features,and the gas permeated into the annular space flows along the metal *** assess the complex gas transport behavior in long-distance gas flexible pipes,a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes,the diffusion of gas in the inner liner,and the gas seepage in the annular space under varying permeable properties of the *** addition,the effect of a variable temperature is accounted.A numerical calculation method is accordingly constructed to solve the coupling mathematical *** annular permeability was shown to significantly influence the distribution of annular *** permeability increases,the annular pressure tends to become more uniform,and the annular pressure at the wellhead rises more *** annular pressure relief followed by shut-in,the pressure increase follows a convex *** simulating the pressure recovery pattern after pressure relief and comparing it with test results,we deduce that the annular permeability lies between 123 and 512 m *** results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources.

关键词： Offshore resources development Transport security Long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation

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Quantum Codes from Constacyclic Codes over Polynomial Residue Rings

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Chinese Journal of Electronics 2019年第6期28卷 1131-1138页

作者： DING jian LI Hongju liang Jing TANG Yongsheng College of Mathematics and Informatics Fujian Normal University Fujian Provincial Key Lab of Network Security and Cryptology Fujian Normal University Department of General Education Anhui Xinhua University School of Mathematics and Statistics Hefei Normal University

Sufficient and necessary conditions for Hermitian（1 + λu）-constacyclic self-orthogonal codes over F;m +uF;m are obtained, where λ is a unit of F;m +uF;*** on this, a new method for the construction of p;ary quantum codes from the obtained Hermitian（1 + λu）-constacyclic self-orthogonal codes over F;m +uF;m is *** an example, [[p;-1, p;-2d + 1, d]];m quantum MDS codes are constructed for 1 ≤ d ≤（p;+ 1）/2 and p ≠ 2, as well as some other quantum codes.

关键词： Quantum code Quantum MDS code Constacyclic code Self-orthogonal code

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A Numerical Study on the Water Impact of the Rigid/Elastic Box-Like Structure

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China Ocean Engineering 2023年第2期37卷 333-342页

作者： YANG jian SUN Zhao-chen liang Shu-xiu State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Recent damages to the box-like structures caused by wave slamming have made it necessary to study the impact problems of this kind of structure. This paper showed findings from numerical simulations of the rigid/elastic structures, aiming to gain insights into the characteristics of the problem. The results of the rigid cases showed the significance of air compressibility during the impact process, while the slamming phenomena became quite different without the effect. In the elastic cases, the trapped air made the structure vibrate at frequencies much smaller than its eigenfrequencies. Besides, the structural deformation made it easy for the trapped air to escape outwards, which weakened the air cushioning effect, especially at high impact velocities. The above analysis gives the results when the structural symmetry axis was vertical to the water(vertical impacts). In addition, the results were given when the axis was oblique to the water(oblique impacts). Compared with the vertical cases, the impact phenomena and structural response showed asymmetry. This work used the computational fluid dynamics(CFD) method to describe fluid motion and the finite element method(FEM) for the deformable structure. A two-way coupling approach was used to deal with the fluid-structure interaction in the elastic cases.

关键词： water impact fluid-structure interaction air compressibility box-like structures two-way coupling

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Spur Gear Tooth Pitting Propagation Assessment Using Model-based Analysis

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1369-1382页

作者： Xi-Hui liang Zhi-liang Liu Jun Pan Ming jian Zuo Department of Mechanical Engineering University of Alberta School of Mechatronics Engineering University of Electronic Science and Technology Key Laboratory of Reliability Technology for Mechanical and Electrical Product of Zhejiang Province Zhejiang Sci-Tech University

Tooth pitting is a common failure mode of a gearbox. Many researchers investigated dynamic properties of a gearbox with localized pitting damage on a single gear tooth. The dynamic properties of a gearbox with pitting distributed over multiple teeth have rarely been investi- gated. In this paper, gear tooth pitting propagation to neighboring teeth is modeled and investigated for a pair of spur gears. Tooth pitting propagation effect on time-vary- ing mesh stiffness, gearbox dynamics and vibration char- acteristics is studied and then fault symptoms are revealed. In addition, the influence of gear mesh damping and environmental noise on gearbox vibration properties is investigated. In the end, 114 statistical features are tested to estimate tooth pitting growth. Statistical features that are insensitive to gear mesh damping and environmental noise are recommended.

关键词： Mesh stiffness Mesh damping Geardynamics Vibration Statistical feature Dynamicsimulation

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Enhanced strength and electrical conductivity of Al-0.3Ce alloy simultaneously with Ti(C,N)nanoparticle addition

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Rare Metals 2021年第7期40卷 1890-1896页

作者： Wan-Peng Li Yu-liang Zhang jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Ti(C,N)nanoparticles were added to an Al-0.3 Ce alloy by ultrasonic *** annealing at 570℃for4 h afforded the ultimate tensile strength of 79 MPa and electrical conductivity of 64.0%IACS for the Al-0.3 Ce alloy with1.5 vol%Ti(C,N)*** performance parameters were improved by 23.4%and 0.6%IACS,respectively,compared with those of casting refining pure aluminum(64 MPa and63.4%IACS).This could be explained by the following *** addition of Ti(C,N)nanoparticles could significantly refine the grain of Al-0.3 Ce ***,most of the coarse strip-shaped second phases distributed at the grain boundaries in Al-0.3 Ce were also transformed into spherical microparticles distributed in the grains,with micro-nano hierarchical structures comprising orientated nanosized strip phases with lengths of~400 nm and widths of~100 ***,a fine micro-nano hierarchical spherical structure could be obtained after annealing at 570℃for 4 *** numbers of micro-nano hierarchical spherical structures also increased due to the precipitation of pseudosolution Ce from the aluminum matrix during the annealing treatment.

关键词： Conductive aluminum alloy Ti(C,N)nanoparticles Ce Micro-nano hierarchical spherical structure Annealing treatment

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Dynamic p-y curves for vertical and batter pile groups in liquefied sand

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Earthquake Engineering and Engineering Vibration 2022年第3期21卷 605-616页

作者： Zhang jian Li Yurun Rong Xian liang Yan School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Campus Construction and Management Hebei University of TechnologyTianjin 300401China

In this study,centrifuge model tests of vertical and batter pile groups in liquefied sand were conducted on a centrifuge shaking *** dynamic p-y curves for these pile groups before and during sand liquefaction were obtained from calculations based on test *** results confirm that liquefaction contributes to a reduction in the energy consumption of pile foundations,with the degradation effect being more pronounced for batter pile *** shallow depths,the difference in the backbone gradients of the p-y curves after liquefaction for vertical and batter pile groups indicates that the lateral stiffness of a batter pile group is greater than that of a vertical pile *** shaking intensity increases,the lateral stiffness of a vertical pile group increases with depth during the late stage of sand ***,the lateral stiffness of a batter pile group during liquefaction does not vary with *** results of this study provide a reference for the seismic design of vertical and batter pile groups in liquefied soil.

关键词： soil liquefaction pile-soil interaction p-y curve centrifuge shaking table

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