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Spatial-temporal Pattern and Population Driving Force of Land Use Change in Liupan mountains Region, Southern Ningxia, China

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Chinese Geographical Science 2008年第4期18卷 323-330页

作者： QUAN Bin m J m ROmKENS TAO Jianjun LI Bicheng LI Chaokui yu Guanghui CHEN Qichun Institute of Geospatial Information Science Hunan University of Science and Technology Xiangtan 411201 China USDA/ARS National Sedimentation Laboratory P O. Box 1157 Oxford MS 38655 USA Researeh Center of Soil and Water Conservation and Ecological Environment Chinese Academy of Sciences and Ministry of Education Northwest Sci-tech University of Agriculture and Forestry Yangling 712100 China

The Liupan mountains is located in the southern Ningxia Hui Autonomous Region of China, which forms an important dividing line between landforms and bio-geographic regions. The populated part of the Liupan mountains region has suffered tremendous ecological damages over time due to population pressure, excessive demand and inappropriate use of agricultural land resources. In this paper, datasets of land use between 1990 and 2000 were obtained from Landsat Tm imagery, and then spatial models were used to characterize landscape conditions. Also, the relationship between the population density and land use/cover change (LUCC) was analyzed. Results indicate that cropland, forestland, and urban areas have increased by 44,186ha, 9001ha and 1550ha, respectively while the grassland area has appreciably decreased by 54,025ha in the study period. The decrease in grassland was most notable. Of the grassland lost, 49.4% was converted into cropland. The largest annual land conversion rate in the study area was less than 2%. These changes are attributed to industrial and agricultural development and population growth. To improve the eco-economic conditions in the study region, population control, urbanization and development of an ecological friendly agriculture were suggested.

关键词： land use/cover change (LUCC) GIS remote sensing Liupan mountains region Loess Plateau

Guided Waves in the multilayered One-Dimensional Hexagonal Quasi-crystal Plates

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Acta mechanica Solida Sinica 2021年第1期34卷 91-103页

作者： B.Zhang J.G.yu X.m.Zhang X.H.Wang School of mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo454003China

Guided waves in the multilayered one-dimensional quasi-crystal plates are,respectively,investigated in the context of the Bak and elasto-hydrodynamic *** curves and phonon and phason displacements are calculated using the Legendre polynomial *** characteristics in the context of these two models are analyzed in *** show that the phonon-phason coupling effects on the first two layers are the same at low frequencies;but,they are more significant on the first layer than those on the second layer at high *** obtained results lay the theoretical basis of guided-wave nondestructive test on multilayered quasi-crystal plates.

关键词： multilayered structures Quasi-crystal plate Guided wave Phonon-phason coupling effect

Study of variable stars associated with maser sources: G025.65+1.05

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Research in Astronomy and Astrophysics 2019年第3期19卷 47-52页

作者： Andrey m.Sobolev Anastasia P.Bisyarina Stanislav yu.Gorda Andrey m.Tatarnikov Astronomical Observatory of the Ural Federal University Sternberg Astronomical Institute of moscow State University

We report variation of K-band infrared(IR) emission in the vicinity of the G025.65+1.05 water and methanol maser source. New observational data were obtained with the 2.5 m telescope at the Caucasian mountain Observatory(CmO) of moscow State University on 2017–09–21 during a strong water maser flare. We found that the IR source situated close to the maser position had decreased brightness in comparison to archive data. This source is associated with a massive young stellar object(mYSO) corresponding to the compact IR source IRAS 18316–0602(RAFGL 7009 S). A similar decrease in K-brightness of the IR source close to the maser position was observed in march 2011 when the water maser experienced a period of increased activity. The dips in mYSO brightness can be related to the maser flare phases. maser flares that are concurrent with dips in the IR emission can be explained if the lower IR radiation field enables a more efficient sink for the pumping cycle by allowing IR photons to escape the maser region.

关键词： techniques photometric-infrared stars-masers

Special Focus on machine-Type Communications

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Science China(Information Sciences) 2017年第10期60卷 5-6页

作者： Xiaofeng TAO Ping ZHANG Victor C.m.LEUNG Songwu LU yu CHEN Beijing University of Posts and Telecommunications The University of British Columbia The University of California

machine-type communication(mTC)refers to the communication between devices with or without the involvement of the network *** recent years,we have witnessed a rapid penetration of embedded devices;and we believed that... 详细信息

关键词： mTC In Special Focus on machine-Type Communications HTC ATS

New methods for processing and interpreting marine magnetic anomalies:Application to structure,oil and gas exploration,Kuril forearc,Barents and Caspian seas

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Geoscience Frontiers 2013年第1期4卷 73-85页

作者： A.m.Gorodnitskiy yu.V.Brusilovskiy A.N.Ivanenko A.m.Filin N.A.Shishkina Shirshov Institute of Oceanology MoscowRussia

New methods are presented for processing and interpretation of shallow marine differential magnetic data, including constructing maps of offshore total magnetic anomalies with an extremely high reso- lution of up to 1-2 nT, mapping weak anomalies of 5-10 nT caused by mineralization effects at the contacts of hydrocarbons with host rocks, estimating depths to upper and lower boundaries of anom- alous magnetic sources, and estimating thickness of magnetic layers and boundaries of tectonic blocks. Horizontal dimensions of tectonic blocks in the so-called ＂seismic gap＂ region in the central Kuril Arc vary from 10 to 100 km, with typical dimensions of 25-30 km. The area of the ＂seismic gap＂ is a zone of intense tectonic activity and recent volcanism. Deep sources causing magnetic anomalies in the area are similar to the ＂magnetic belt＂ near Hokkaido. In the southern and central parts of Barents Sea, tectonic blocks with widths of 30-100 kin, and upper and lower boundaries of magnetic layers ranging from depths of 10 to 5 km and 18 to 30 km are calculated. models of the magnetic layer underlying the mezen Basin in an inland part of the White Sea-Barents Sea paleorift indicate depths to the lower boundary of the layer of 12-30 km. Weak local magnetic anomalies of 2-5 nT in the northern and central Caspian Sea were identified using the new methods, and drilling confirms that the anomalies are related to concentrations of hydrocarbon. Two layers causing magnetic anomalies are identified in the northern Caspian Sea from magnetic anomaly spectra. The upper layer lies immediately beneath the sea bottom and the lower layer occurs at depths between 30-40 m and 150-200 m.

关键词： Geophysical survey magnetic data processing Hydrocarbon prospecting Kuril Arc Barents Sea Caspian Sea

A stable biocompatible porous coordination cage promotes in vivo liver tumor inhibition

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Nano Research 2021年第10期14卷 3407-3415页

作者： yu Liang yu Fang Yong Cui Hongcai Zhou State Key Laboratory for Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Texas A&M UniversityCollege StationTX 77843USA

many emerging strategies in chemo-,gene-,and immunotherapy require the accumulation of reagents in the cell ***,their delivery into the nucleus is often *** delivery could be enhanced with a rationally designed cargo-delivery scaffold,but this approach has rarely been successfully ***,a stable,biocompatible molecular capsule that encapsulates and delivers camptothecin,a DNA topoisomerase I inhibitor,into the nucleus of living cells was *** delivery is facilitated by the ultra-small diameter,zero net charge,and hydrophobicity of the *** encapsulated drug complex displays superior toxicity towards multiple cancer cells over the free drug,the Food and Drug Administration(FDA)approved drugs,as well as conventionally reported drug ***,it inhibits liver cancer tumor growth in a xenograft mouse *** of the properties of such molecular capsules may make it possible to design therapeutic strategies that target specific cell organelles.

关键词： metal-organic polyhedron biocompatible cage compound cavity drug delivery

Transferability of microsatellite markers from Brachypodium distachyon to miscanthus sinensis,a Potential Biomass Crop

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Journal of Integrative Plant Biology 2011年第3期53卷 232-245页

作者： Hua Zhao Jiangyan yu Frank m. You mingcheng Luo Junhua Peng Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical Garden the Chinese Academy of Sciences Wuhan 430074 China Department of Plant Sciences University of California Davis CA 95616 USA Department of Soil and Crop Sciences Colorado State University Fort Collins CO 80523-1170 USA

miscanthus sinensis has high biomass yield and contributed two of the three genomes in m. x giganteus, a bioenergy crop widely studied in Europe and North America, and thus is a potential biomass crop and an important germplasm for miscanthus breeding. molecular markers are essential for germplasm evaluation, genetic analyses and new cultivar development in m. sinensis. In the present study, we reported transferability of simple sequence repeat （SSR） markers from Brachypodium distachyon to m. sinensis. A set of 57 SSR markers evenly distributed across the B. distachyon genome were deliberately designed. Out of these B. distachyon SSR markers, 86.0% are transferable to m. sinensis. The SSR loci amplified in m. sinensis were validated by re-sequencing the amplicons. The polymorphism information content （PIC） of the transferable SSR markers varied from 0.073 to 0.375 with a mean of 0.263, assessed based on 21 m. sinensis genotypes. Phylogenetic tree based on 162 alleles detected by 49 SSR markers could unambiguously distinguish B. distachyon from m. sinensis, and cluster 21 m. sinensis genotypes into three groups that are basically in coincidence with their geographical distribution and ecotype classifications. The markers developed by the comparative genomic approach could be useful for germplasm evaluation, genetic analysis, and marker-assisted breeding in miscanthus.

关键词： BRACHYPODIUm mISCANTHUS mICROSATELLITES (Genetics) GENETIC markers ENERGY crops GENETIC transformation BIOmASS production

A Novel Deep Hybrid Recommender System Based on Auto-encoder with Neural Collaborative Filtering

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Big Data mining and Analytics 2018年第3期1卷 211-221页

作者： yu Liu Shuai Wang m.Shahrukh Khan Jieyu He School of Computer Science and Engineering and also with MOE Key Laboratory of Computer Network and Information Integration Southeast University

Due to the widespread availability of implicit feedback(e.g., clicks and purchases), some researchers have endeavored to design recommender systems based on implicit feedback. However, unlike explicit feedback,implicit feedback cannot directly reflect user preferences. Therefore, although more challenging, it is also more practical to use implicit feedback for recommender systems. Traditional collaborative filtering methods such as matrix factorization, which regards user preferences as a linear combination of user and item latent vectors, have limited learning capacities and suffer from data sparsity and the cold-start problem. To tackle these problems,some authors have considered the integration of a deep neural network to learn user and item features with traditional collaborative filtering. However, there is as yet no research combining collaborative filtering and contentbased recommendation with deep learning. In this paper, we propose a novel deep hybrid recommender system framework based on auto-encoders(DHA-RS) by integrating user and item side information to construct a hybrid recommender system and enhance performance. DHA-RS combines stacked denoising auto-encoders with neural collaborative filtering, which corresponds to the process of learning user and item features from auxiliary information to predict user preferences. Experiments performed on the real-world dataset reveal that DHA-RS performs better than state-of-the-art methods.

关键词： hybrid recommender system neural collaborative filtering auto-encoder implicit feedback

micropillar Cavity Design for 1.55-μm Quantum-Dot Single-Photon Sources

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Journal of Electronic Science and Technology 2019年第3期17卷 221-230页

作者： Hai-Zhi Song Wei Zhang Li-Bo yu Zhiming m.Wang the Institute of Fundamental and Frontier Sciences University of Electronic Science and TechnologyChengdu 610054 Southwest Institute of Technical Physics Chengdu 610041

The 1.55-μm quantum-dot (QD) micropillar cavities are strongly required as single photon sources (SPSs) for silica-fiber-based quantum information processing. Theoretical analysis shows that the adiabatic distributed Bragg reflector (DBR) structure may greatly improve the quality of a micropillar cavity. An InGaAsP/InP micropillar cavity is originally difficult, but it becomes more likely usable with inserted tapered (thickness decreased towards the center) distributed DBRs. Simulation turns out that, incorporating adiabatically tapered DBRs, a Si/SiO2- InP hybrid micropillar cavity, which enables weakly coupling InAs/InP quantum dots (QDs), can even well satisfy strong coupling at a smaller diameter. Certainly, not only the tapered structure, other adiabatic designs, e.g., both DBR layers getting thicker and one thicker one thinner, also improve the quality, reduce the diameter, and degrade the fabrication difficulty of Si/SiO2-InP hybrid micropillar cavities. Furthermore, the problem of the thin epitaxial semiconductor layer can also be greatly resolved by inserting adiabatic InGaAsP/InP DBRs. With tapered DBRs, the InGaAsP/InP-air-aperture micro-pillar cavity serves as an efficient, coherent, and monolithically producible 1.55-μm single-photon source (SPS). The adiabatic design is thus an effective way to obtain prospective candidates for 1.55-μm QD SPSs.

关键词： Cavity distributed Bragg reflectors(DBRs) micropillar quantum dot(QD) single-photon source(SPS)