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Evaluation of global land cover maps for cropland area estimation in the conterminous United States

International Journal of Digital Earth 2015年第2期8卷 102-117页

作者： lu liang Peng Gong Department of Environmental Science Policy and ManagementUniversity of CaliforniaBerkeleyCAUSA Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System ScienceTsinghua UniversityBeijingChina

Global land cover data could provide continuously updated cropland acreage and distribution information,which is essential to a wide range of applications over large geographical *** area estimates were evaluated in the conterminous USA from four recent global land cover products:MODIS land cover(MODISLC)at 500-m resolution in 2010,GlobCover at 300-m resolution in 2009,FROM-GLC and FROM-GLC-agg at 30-m resolution based on Landsat imagery circa 2010 against the US Department of Agriculture survey *** estimators derived from the 30-m resolution Cropland Data Layer were applied to MODIS and GlobCover land cover products,which greatly improved the estimation accuracy of MODISLC by enhancing the correlation and decreasing mean deviation(MDev)and RMSE,but were less effective on GlobCover *** found that,in the USA,the CDL adjusted MODISLC was more suitable for applications that concern about the aggregated county cropland acreage,while FROM-GLC-agg gave the least deviation from the survey at the state *** between land cover map estimates and survey estimates is significant,but stronger at the state level than at the county *** regions where most mismatches happen at the county level,MODIS tends to underestimate,whereas MERIS and Landsat images incline to *** uncertainties should be taken into consideration in relevant *** interannual and seasonal effects,R 2 of the FROM-GLC regression model increased from 0.1 to 0.4,and the slope is much closer to *** analysis shows that images acquired in growing season are most suitable for Landsat-based cropland mapping in the conterminous USA.

关键词： cropland area global land cover FROM-GLC area estimation NASS survey

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A Degree Condition for Graphs Having All(a,b)-parity Factors

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 656-664页

作者： Hao-dong LIU Hong-liang lu School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China

Let a and b be positive integers such that a≤b and a≡b(mod 2).We say that G has all(a,b)-parity factors if G has an h-factor for every function h:V(G)→{a,a+2,…,b-2,b} with b|V(G)| even and h(v)≡b(mod 2) for all v∈V(G).In this paper,we prove that every graph G with n≥2(b+1)(a+b) vertices has all(a,b)-parity factors if δ(G)≥(b^(2)-b)/a,and for any two nonadjacent vertices u,v ∈V(G),max{d_(G)(u),d_(G)(v)}≥bn/a+***,we show that this result is best possible in some sense.

关键词： degree condition all(a,b)-factors

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PREPARATION AND CHARACTERIZATION OF INCluSION COMPLEXES OF TWO-ARM LINEAR AND FOUR-ARM STAR-SHAPED POLY(ε-CAPROLACTONE)S WITHα-CYCLODEXTRIN

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Chinese Journal of Polymer Science 2006年第3期24卷 245-252页

作者： lu Wang Jing-liang Wang 董常明 Department of Polymer Science ＆ Engineering School of Chemistry and Chemical Technology Shanghai Jiao Tong University Shanghai 200240 China

Both four-ann star-shaped poly（ε-caprolactone）（4sPCL） and two-ann linear PCL （2LPCL） were synthesized and their inclusion complexation with α-cyclodextrin （α-CD） were studied. The inclusion complexes （ICs） formed between the PCL polymers and α-CD were characterized by ^1H-NMR, DSC, TGA, WAXD, and FT-1R, respectively. Both branch ann number and molecular weight of the PCL polymers have apparent effect on the stoichiometry （CL：CD, mol：mol） of these ICs. All these analytical results indicate that the branch arms of the PCL polymers are incorporated into the hydrophobic α-CD cavities and their original crystalline properties are completely suppressed. Moreover, the inclusion complexation between two-ann linear or four-ann star-shaped PCL polymers and α-CD not only enhances the thermal stability of the guest PCL polymers but also improves that of α-CD.

关键词： Inclusion complexes Linear poly(ε-caprolactone) Star-shaped poly(ε-caprolactone) Thermal stability.

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Nanoscale ultraviolet photodetectors based on one- dimensional metal oxide nanostructures

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Nano Research 2015年第2期8卷 382-405页

作者： Wei Tian Hao lu liang Li College of Physics Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology SoochowUniversity Suzhou 215006 China

Among the important optoelectronic devices, ultraviolet （UV） photodetectors show wide applications in fire monitoring, biological analysis, environmental sensors, space exploration, and UV irradiation detections. Research interest has focused on the utilization of one-dimensional （1D） metal oxide nanostructures to build advanced UV photodetectors through various processes. With large surface-to-volume ratio and well-controlled morphology and composition, 1D metal oxide nanostructures are regarded as promising candidates as components for building photodetectors with excellent sensitivity, superior quantum efficiency, and fast response speed. This article reviews the latest achievements with 1D metal oxide nanostructures reported over the past five years and their applications in UV light detection. It begins with an introduction of 1D metal oxide nanostructures, and the significance, key parameters and types of photo- detectors. Then we present several kinds of widely-studied 1D nanostructures and their photodetection performance, focusing on binary oxides with wide- bandgap （such as ZnO, SnO2, Ga203, Nb2Os, and WO3） and ternary oxides （such as Zn2SnO4, Zn2GeO4, and In2Ge2OT）. Finally, the review concludes with our perspectives and outlook on future research directions in this field.

关键词： metal oxide 1D nanostructures UV light photodetector nanodevices

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Analysis of the one-decoy-state SARG04 quantum cryptography protocol in the presence of afterpulse effects

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Communications in Theoretical Physics 2024年第6期76卷 66-71页

作者： Hu Nian Ya-Feng Nie Chun-Mei Zhang liang-liang lu Key Laboratory of Optoelectronic Technology of Jiangsu Province School of Physical Science and TechnologyNanjing Normal UniversityNanjing 210023China Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China Hefei National Laboratory Hefei 230088China

The SARG04 quantum key distribution protocol can offer greater robustness against photon number splitting attacks than the BB84 protocol that is implemented with weak *** this paper,we propose a tight key analysis for the SARG04 protocol,by considering the one-decoy method and investigating its performance under the influence of a detector *** results demonstrate that an increase in block size leads to a slight increase in both the secure key rate and the maximum transmission ***,the detector afterpulse plays a crucial role in practical applications and has a more pronounced effect on the SARG04 protocol compared to the BB84 protocol.

关键词： Quantum key distribution SARG04 protocol one decoy afterpulse

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Two-Variable Hermite Function as Quantum Entanglement of Harmonic Oscillator＇s Wave Functions

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Communications in Theoretical Physics 2007年第6期47卷 1024-1028页

作者： lu Hai-liang FAN Hong-Yi Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

We reveal that the two-variable Hermite function hm,n, which is the generalized Bargmann representation of the two-mode Fock state, involves quantum entanglement of harmonic oscillator＇s wave functions. The Schmidt decomposition of hm,n is derived. It also turns out that hm,n can be generated by windowed Fourier transform of the single-variable Hermite functions. As an application, the wave function of the two-variable Hermite polynomial state S（γ）Hm,n （μa1^＋, μa2^＋│00〉, which is the minimum uncertainty state for sum squeezing, in （ η│representation is calculated.

关键词： two-variable Hermite function quantum entanglement Bargmann representation Schmidt decomposition

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Land Use and Land Cover Change on Slope in Qiandongnan Prefecture of Southwest China

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Journal of Mountain Science 2014年第3期11卷 762-773页

作者： lu liang GUO luo ZHAO Song-ting College of Life and Environmental Science Minzu University of China Geomatics Centre of Zhejiang Beijing Institute of Landscape Architecture

This study uses DEM （Digital Elevation Model） data and remote sensing maps of the study area in 1993, 1999, and 2009 to analyze the slope gradient change of land use patterns in Qiandongnan Prefecture, Guizhou province, China. The land use data were classified into five types, forest, farmland, grassland, water and built-up, the slope gradients were divided into four grades. Indices for analyzing land use features were defined by their proportions, transformation matrixes, land use degree and changes The results showed that all land use types can be found at every gradient. Generally, with the slope degree increased, the area of forest being augmented as well, while the area of the other land use types （farmland, grassland and build-up） declined. Moreover, a mass of farmland were shifted from other land use types from o° to 25°, while a quantity of forest were transformed from the other land use types on 〉 25° from 2993 to 2009. In terms of land use degree and changes, the area of farmland and buildup land use types decreased when slope degree increased. Finally, we calculated the five landscape pattern metrics： Patch Density （PD） value, Largest Patch Index （LPI）, Shannon＇s Diversity Index （SHDI）, Area-Weighted Mean Shape Index （AWMSI） and Contagion Index （CONTAG）. The results of metricsanalysis showed that PD values, SHDI values and CONTA values had a similar variation trend, that is, they decreased when slope degree increased. There was no obvious variation trend on LPI value.

关键词： Land use Land cover change Spatialgradient slope Landscape metrics Qiandongnanprefecture

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Lasiodiplodia pseudotheobromae causes stem canker of Chinese hackberry in China

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Journal of Forestry Research 2020年第6期31卷 2571-2580页

作者： lu liang Huan Li Lifeng Zhou Fengmao Chen Co-Innovation Center for Sustainable Forestry in Southern China College of ForestryNanjing Forestry UniversityNanjing 210037JiangsuPeople’s Republic of China

Chinese hackberry(Celtis sinensis Pers.)is an adaptable species widely growing in southern *** symptoms of canker on stems of seedlings were discovered mid-July 2017 in Shuyang,Jiangsu *** diseased portions of the stems were dark brown due to discoloured *** seedlings showed symptoms of wilting,leaf fall,twig dieback,and tissue *** outbreak period was concentrated in July and August,suggesting that the disease spread during summer *** fungal causal agents were isolated from naturally infected canker tissue and discoloured *** isolate from xylem tissue with a high frequency(>50%)was named Ls7 *** tests were carried out on 4-yearold *** symptoms of canker began to develop 20 days after inoculation with Ls7 isolate and by day 35,there were dark,enlarged longitudinal lesions.A phylogenetic tree of the isolate was developed using the internal transcribed spacer,elongation factor-1α(tef1-α),β-tubulin gene(TUB)and RNA polymerase II subunit primer genes(RPB2).Based on morphological features and phylogenetic information,the pathogen was identifi ed as Lasiodiplodia *** is the fi rst report of *** causing canker on Chinese hackberry stems in China.

关键词： Botryosphaeriaceae Plant pathogen Tree disease

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Adaptive Change Detection for Long-Term Machinery Monitoring Using Incremental Sliding-Window

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1338-1346页

作者： Teng Wang Guo-liang lu Jie Liu Peng Yan Key Laboratory of High-Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong University Department of Mechanical and Aerospace Engineering Carleton University

Detection of structural changes from an opera- tional process is a major goal in machine condition moni- toring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detection delay that limits their usages in real applications. This paper presents a new adaptive real-time change detection algorithm, an extension of the recent research by combin- ing with an incremental sliding-window strategy, to handle the multi-change detection in long-term monitoring of machine operations. In particular, in the framework, Hil- bert space embedding of distribution is used to map the original data into the Re-producing Kernel Hilbert Space （RK_HS） for change detection; then, a new adaptive threshold strategy can be developed when making change decision, in which a global factor （used to control the coarse-to-fine level of detection） is introduced to replace the fixed value of threshold. Through experiments on a range of real testing data which was collected from an experimental rotating machinery system, the excellent detection performances of the algorithm for engineering applications were demonstrated. Compared with state-of- the-art methods, the proposed algorithm can be more suitable for long-term machinery condition monitoring without any manual re-calibration, thus is promising in modern industries.

关键词： Machine monitoring Change detection Long-term monitoring Adaptive threshold

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Depression behaviors of N-thiourea-maleamic acid and its adsorption mechanism on galena in Mo-Pb flotation separation

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International Journal of Mining Science and Technology 2022年第1期32卷 181-189页

作者： liang lu Wei Xiong Yangge Zhu Xingrong Zhang Yongxing Zheng State Key Laboratory of Mineral Processing Beijing 102628China BGRIMM Technology Group Beijing 102628China China-South Africa Belt and Road Joint Laboratory on Sustainable Exploration and Utilization of Mineral Resources Beijing 102628China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming 650093China

In present study,a novel organic depressant N-thiourea-maleamic acid(TMA)was synthesized and applied as a galena depressant in the flotation separation of Mo-Pb *** depression behaviors of TMA were tested through flotation experiments.A wider separation window for single minerals over 90.0%was obtained at 30.0 mg/L TMA,confirming that TMA could depress galena significantly,while effected molybdenite floatability *** effective separation was obtained for artificially mixed minerals and actual Mo-Pb *** adsorption mechanism on galena was revealed by UV-Vis spectra,zeta potential tests,Fourier transform infrared spectroscopy(FT-IR)analysis,contact angle tests and X-ray photoelectron spectroscopy(XPS)*** zeta potentials of galena became more negative and the contact angle of galena dropped from initial 74.36°to 57.8°with 30.0 mg/L TMA depressant,inferring that TMA had adsorbed on galena *** analysis results of UV-Vis spectra,FT-IR and XPS gave further evidence that TMA might chemisorb on galena surface via Pb sites on galena surface and the thiourea group in TMA molecular structure,while the carboxyl group played a role of hydrophilicity.

关键词： Molybdenite Galena TMA Separation Adsorption

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