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| 1 | Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s显示文摘Land-use/land-cover 变化(LUCC ) 有连接到人和自然相互作用。瓷器 Land-Use/cover 数据集(CLUD ) 从 1980 年代末在 5 年的间隔定期被更新到 2010,与基于 Landsat TMETM+ 图象的标准过程。陆地使用动态区域化方法被建议分析主要陆地使用变换。在国家规模的陆地使用变化的空间与时间的特征,差别,和原因然后被检验。主要调查结果如下被总结。越过中国的陆地使用变化(LUC ) 在最后 20 年(19902010 ) 里在空间、时间的特征显示了一个重要变化。农田变化的区域在南方减少了并且在北方,而是仍然是的全部的区域增加了几乎未改变。回收农田从东北被转移到西北。布满建筑物陆地很快膨胀了,主要在东方被散布,并且逐渐地展开到中央、西方的中国。树林首先减少了,然后增加但是荒芜的区域是反面。草地继续减少。在中国的 LUC 的不同空间模式被发现在之间迟了第 20 世纪并且早第 21 世纪。原版 13 个 LUC 地区在一些地区被边界的变化由 15 个单位代替。包括的这些变化(1 ) 的主要空间特征加速的扩大布满建筑物在 Huang-Huai-Hai 区域,东南的沿海的区域,长江的中流区域,和四川盆登陆;(2 ) 从东北中国和东方内部蒙古在北方转移了陆地开垦到绿洲在西北中国的农业区域;(3 ) 从在到稻的东北中国的喂雨的农田的连续转变回答;并且(4 ) 为在内部蒙古,黄土高原,和西南的多山的区域的南部的农业牧剧的交错群落的格林工程的谷物的有效性。在最后二十年,尽管在北方的气候变化在农田影响了变化,政策规定和经济驱动力仍然是越过中国的 LUC 的主要原因。在第 21 世纪的第一十年期间,在陆地使用模式驾驶了变化的人为的因素从单程的陆地开发转移了强调到开发和保存。动态区域化方法被用来在单位的 zoning 边界,地区的内部特征,和生长和减少的空间模式分析变化。结果揭示了变化过程的模式,也就是 LUC 的过程和在在不同阶段的特征的地区性的差别。地区的生长和减少在这动态 LUC zoning,在统一边界的变化,和在前者和后者十年之间的变化紧张的特征期间被检验。在为在不同类型和陆地使用的不同区域的变化的陆地使用和原因的模式和过程之间的其他的转变的模式被探索。 | LIU Jiyuan KUANG Wenhui ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng | 2014 | Journal of Geographical Sciences2014，24，2： | 245 |
| 2 | Prescribed Performance Finite-Time Tracking Control for Uncertain Nonlinear Systems显示文摘This work investigates the finite-time tracking control problem for a class of uncertain strict-feedback nonlinear systems from a new perspective. First, a novel concept called finite-time performance function (FTPF) is defined. Further, a new sufficien t condition of finite-time st ability is derived and the tracking error can converge to a predefined region within a finite-time interval. The design process of the proposed technique is simpler. Finally, four simulation examples are carried out to illustrate the effectiveness of presented method. | JING Yuanwei LIU Yang ZHOU Shaowei | 2019 | Journal of Systems Science & Complexity2019，32，3： | 11 |
| 3 | Reconfigurable intelligent surfaces for wireless communications:Overview of hardware designs,channel models,and estimation techniques显示文摘The demanding objectives for the future sixth generation(6G)of wireless communication networks have spurred recent research efforts on novel materials and radio-frequency front-end architectures for wireless connectivity,as well as revolutionary communication and computing paradigms.Among the pioneering candidate technologies for 6G belong the reconfigurable intelligent surfaces(RISs),which are artificial planar structures with integrated electronic circuits that can be programmed to manipulate the incoming electromagnetic field in a wide variety of functionalities.Incorporating RISs in wireless networks have been recently advocated as a revolutionary means to transform any wireless signal propagation environment to a dynamically programmable one,intended for various networking objectives,such as coverage extension and capacity boosting,spatiotemporal focusing with benefits in energy efficiency and secrecy,and low electromagnetic field exposure.Motivated by the recent increasing interests in the field of RISs and the consequent pioneering concept of the RIS-enabled smart wireless environments,in this paper,we overview and taxonomize the latest advances in RIS hardware architectures as well as the most recent developments in the modeling of RIS unit elements and RIS-empowered wireless signal propagation.We also present a thorough overview of the channel estimation approaches for RIS-empowered communications systems,which constitute a prerequisite step for the optimized incorporation of RISs in future wireless networks.Finally,we discuss the relevance of the RIS technology in the latest wireless communication standards,and highlight the current and future standardization activities for the RIS technology and the consequent RIS-empowered wireless networking approaches. | Mengnan Jian George C.Alexandropoulos Ertugrul Basar Chongwen Huang Ruiqi Liu Yuanwei Liu Chau Yuen | 2022 | Intelligent and Converged Networks2022，3，1： | 9 |
| 4 | Impacts of ecological restoration projects on agricultural productivity in China显示文摘在农田数量和质量的变化由于陆地使用是国家食物安全的批评担心,特别地为中国。尽管有重要生态的效果,生态的恢复节目(ERP ) ,从 1999 开始了,显然改变了瓷器农田和农业生产率的空间模式。从 2000 ~ 2008 把动态数据基于农田首先与主要生产率建模的 30-m 分辨率和基于卫星的网源于卫星图象,我们在 ERP 引起的农业生产率上识别了影响,包括为格林的谷物,节目(GFGP ) 和到湖(RCTL ) 的回收农田编程序。我们的结果显示农业生产率与 132.67lis 的率输了。在 R 的射击的 Pb 的累积。pseudoacacia 比另外的种类显著地高。在学习区域的土壤的 Pb 的数量是 s 吗?? | QIN Yuanwei YAN Huimin LIU Jiyuan DONG Jinwei CHEN Jingqing XIAO Xiangming | 2013 | Journal of Geographical Sciences2013，23，3： | 8 |
| 5 | Microstructure and properties of novel Al-Ce-Sc,Al-Ce-Y,Al-Ce-Zr and Al-Ce-Sc-Y alloy conductors processed by die casting,hot extrusion and cold drawing显示文摘In order to overcome the trade-off between the strength and electrical conductivity of aluminum alloy conductors,the new Al-Ce-Sc,Al-Ce-Y,Al-Ce-Zr and Al-Ce-Sc-Y alloys were prepared by die casting,high temperature homogenization treatment,hot extrusion and cold drawing.Adding Sc and Y eliminated the dendrite segregation of the as-cast Al-0.2 Ce alloy and promoted the formation of equiaxed grains with the average grain size of 142.5μm.The Al-0.2 Ce-0.2 Sc-0.1 Y alloy inherited the great tensile properties of Al-0.2 Ce-0.2 Sc alloy and the high electrical conductivity of Al-0.2 Ce-0.1 Y alloy simultaneously.After cold drawing and annealing at 200℃for 5 h,the ultimate tensile strength of Al-0.2 Ce-0.2 Sc-0.1 Y alloy reached 200 MPa and 198 MPa,the elongation reached 6.8%and 8.5%,and the electrical conductivity reached 61.01%and 61.77%,respectively.The main second phase of Al-0.2 Ce-0.2 Sc-0.1 Y alloy after hot extrusion were Al_(13)Fe_3 Ce containing a few Y and Si atoms.The larger size and proportion of the second phase greatly reduced the concentration of solute Fe and Si atoms and the addition of Y significantly decreased the density of defects after cold drawing compared to Al-0.2 Ce-0.2 Sc alloy,which improved electrical conductivity of the alloy.Furthermore,the dispersed and coherent nano-size Al_3 Sc precipitions of Al-0.2 Ce-0.2 Sc-0.1 Y alloy greatly improved strength,elongation and heat resistance.Compared with Al-0.2 Ce-0.2 Sc alloy,the lower density of dislocation,stacking fault and subgrain boundary and the larger size of Al_3 Sc precipitions with enrichment of Y atoms enable the Al-0.2 Ce-0.2 Sc-0.1 Y alloy to maintain high strength,elongation and electrical conductivity after annealing. | Weiyi Wang Qinglin Pan Geng Lin Xiaoping Wang Yuqiao Sun Xiangdong Wang Ji Ye Yuanwei Sun Yi Yu Fuqing Jiang Jun Li Yaru Liu | 2020 | Journal of Materials Science & Technology2020，58，23： | 4 |
| 6 | Space-confined growth of monolayer ReSe2 under a graphene layer on Au foils显示文摘Vertical heterostructures based on two-dimensional(2D)materials have attracted widespread interest for their numerous applications in electronic and optoelectronic devices.Herein,we report the direct construct!on of an abnormal graphene/ReSe2 stack on Au foils by a two-step chemical vapor deposition(CVD)strategy.During the second growth stage,mono layer ReSe2 is found to prefere ntially evolve at the irUerface between the first-grown graphene layer and the Au substrate.The unusual stacking behavior is unraveled by in-situ'cutting open'the upper graphene from the defects to expose the lower ReSe2 using scanning tunneling microscopy(STM).From combination of these results with density functional theory calculations,the domain boundaries and edge sites of graphene are proposed to be adsorption sites for Re and Se precursors,further facilitating the growth of ReSe2 at the van der Waals gap of graphene/Au.This work hereby offers an intriguing strategy for obtaining vertical 2D heterostructures featured with an ultra-clean interface and a designed stacking geometry. | Chunyu Xie Shaolong Jiang Xiaolong Zou Yuanwei Sun Liyun Zhao Min Hong Shulin Chen Yahuan Huan Jianping Shi Xiebo Zhou Zhepeng Zhang Pengfei Yang Yuping Shi Porun Liu Qing Zhang Peng Gao Yanfeng Zhang | 2019 | Nano Research2019，12，1： | 4 |
| 7 | Evaluating the safety of high arch dams with fractures based on numerical simulation and geomechanical model testing显示文摘It is important to estimate the probability of fracture extension and its impact on the safety of arch dams with fractures. Numerical simulation and geomechanical model test were combined to evaluate the overall stability and the extension probability of fractures. Numerical simulation forecasted the dam displacement and the operating behavior based on the parameters obtained from the back analysis. Geomechanical model test was based on small block masonry and the models with or without fractures were both tested. The results show that the deformation of dams is in line with general rules at a normal water load and the extension probability of the existing fractures is very small, which has no significant impact on the global stability of dams. Moreover, the failure process of arch dams with the existing fractures in dams at overload scenarios is similar to the one without the embedded fractures, i.e., the failure crack which is not caused by the existing fractures inside comes into being on the surface of dams itself. | HE Zhu LIU YaoRu PAN YuanWei YANG Qiang | 2015 | Science China(Technological Sciences)2015，58，10： | 3 |
| 8 | Experimental study of single-row chevron-jet impingement heat transfer on concave surfaces with different curvatures显示文摘To address the curvature effect on single-row chevron-nozzle jet impingement heat transfer on concave surface,a series of experiments are conducted in the present investigation.Four concave surfaces including one semi-cylindrical concave surface and three parabolic concave surfaces with different width-to-depth ratios are tested under three typical Reynolds numbers(Re=5000,10000 and 15000)and several dimensionless nozzle-to-surface distances ranging from 1 to 8.The results show that the concave curvature has a clear impact on chevron-nozzle jet impingement heat transfer,tightly dependent on jet Reynolds number and impinging distance.In general,the semicylindrical concave surface produces the highest longitudinally-averaged Nusselt number at the leading line of concave surface.Under a low jet Reynolds number,the parabolic concave surface with a highly curved curvature produces higher longitudinally-averaged Nusselt number at the leading line and more uniform longitudinally-averaged Nusselt number distribution along the curvilinear direction.However,the longitudinally-averaged Nusselt number at the leading line of concave surface is the lowest for the highly curved surface under a high jet Reynolds number and large impinging distance.In comparison with the round-nozzle,chevron nozzle plays a more significant role on improving jet impingement heat transfer at small impinging distances. | Yuanwei LYU Jingzhou ZHANG Xichen LIU Yong SHAN | 2019 | Chinese Journal of Aeronautics2019，32，10： | 3 |
| 9 | Block copolymerization of poly (diethylene glycol phthalic anhydride and methyl methacrylate initiated by potassium diperiodatonickelate (Ⅳ)显示文摘 | Liu Yinghai Bai Libin Zhou Weiqi Liu Yuanwei Li Yanxiang Deng Kuilin | | 0，，02： | 1 |
| 10 | Surface Cu^(+) modified ZnIn_(2)S_(4) for promoted visible-light photocatalytic hydrogen evolution显示文摘Surface modification by metal ion has been considered a promising strategy to enhance the photocatalytic activity by extending optical response and improving charge separation and transportation.Here,univalent copper species were modified on ZnIn_(2)S_(4)photocatalyst via an in-situ photodeposition method,exhibiting a much higher H2evolution rate of 41.10±3.43 mmol g^(-1)h^(-1)and an impressive apparent quantum efficiency(AQE)of 20.81%at 420±15 nm.Our characterizations indicate that the surface modification by copper species can broaden light utilization as well as promote charge separation and transportation.Besides,the density functional theory(DFT)results further exhibit that the energy levels(LUMO and HOMO)for copper-surface modified ZnIn_(2)S_(4)present spatial separation,locating on the Zn-S and In-S layers,respectively,which can suppress the recombination of electron and hole and thus achieves higher photocatalytic H2evolution efficiency. | Wen Li Jia Wen Jing Li Hai Yang Yuan Xuefeng Wu Yuanwei Liu Sheng Dai Qilin Cheng Peng Fei Liu Hua Gui Yang | 2022 | Journal of Energy Chemistry2022，31，11： | 1 |
| 11 | The Design of Surface Geometric Microtexture Based on Function 显示文摘 | LI Bokui LIU Yuanwei ZUO Dunwen | 2010 | Applied Mechanics and Materials2010，33，： | 1 |
| 12 | Performance Improvement of Single Screw Compressor by Meshing Clearance Adjustment Used in Refrigeration System显示文摘The single screw compressor(SSC)is widely used in air compression and refrigeration systems due to its many advantages.The meshing clearance between the screw groove and gate rotor teeth flank has a significant influence on the compressor performance.In this paper,mathematical calculation models describing the internal working process of the SSC are established in order to evaluate the thermal dynamic characteristics of the compressor under varying meshing clearance heights.The refrigerating capacity,volume efficiency and adiabatic efficiency of the SSC are calculated and discussed.Three prototypes,with different meshing clearance heights,were manufactured to study the internal influence mechanisms.The theoretical model was verified using experimental data and the calculation results strongly agreed with the experimental results.Results demonstrate that comparisons of volume efficiency and adiabatic efficiency between the measured and calculated results exhibited deviations of 3.64%-7.98%and 5.92%-9.4%,respectively.Based on the models,analysis under varying meshing clearance heights and working conditions was performed.Taking into account working performance,actual manufacturing conditions and manufacturing cost limitations,a meshing clearance height range from 0.01 mm to 0.08 mm is suggested.This study can provide important theoretical data and experimental support for the design,manufacturing and optimization of single screw compressors. | LU Yuanwei LIU Shanwei WU Yuting LEI Biao ZHI Ruiping WEN Qiangyu MA Chongfang | 2021 | Journal of Thermal Science2021，30，1： | 1 |
| 13 | Solvothermal synthesis of spherical YAG powders via different precipitants显示文摘 | Zuogui Wu Xudong Zhang Wen He Yuanwei Du Naitao Jia Pengcheng Liu Fanqing Bu | 2008 | Journal of Alloys and Compounds2008，，1： | 1 |
| 14 | A universal etching-free transfer of MoS2 films for applications in photodetectors显示文摘从生长底层转移瞬间 2 电影到目标底层上是为他们的实际应用的一个关键问题。而且,避免样品降级和底层破坏仍然是大挑战,因为当前的转移方法不可避免地采用蚀刻的湿化学药品,处理。我们为由使用 ultrasonication 转移瞬间 2 电影到任意的底层上开发了一个蚀刻免费的转移方法。简短,在在聚合物涂的瞬间 2 之间的接口的产生 ultrasonication 的 microbubbles 的倒塌电影和底层导致足够的力量到 delaminate 瞬间 2 电影。用这个方法,瞬间 2 电影能从所有底层(硅石,云母,锶 titanate,和蓝宝石) 被转移并且保留原来的样品形态学和质量。这个方法保证一个简单转移过程并且允许生长底层的复用,没有包含任何危险蚀刻剂。蚀刻免费的转移方法是可能的在光电探测器支持瞬间 2 的宽广应用程序。 | Donglin Ma Jianping Shi Qingqing Ji Ke Chen Jianbo Yin Yuanwei Lin Yu Zhang Mengxi Liu Qingliang Feng Xiuju Song Xuefeng Guo Jin Zhang Yanfeng Zhang Zhongfan Liu | 2015 | Nano Research2015，8，11： | 1 |
| 15 | Continued Increases of Gross Primary Production in Urban Areas during 2000-2016显示文摘Urbanization affects vegetation within city administrative boundary and nearby rural areas.Gross primary production(GPP)of vegetation in global urban areas is one of important metrics for assessing the impacts of urbanization on terrestrial ecosystems.To date,very limited data and information on the spatial-temporal dynamics of GPP in the global urban areas are available.In this study,we reported the spatial distribution and temporal dynamics of annual GPP during 2000–2016 from 8,182 gridcells(0.5°by 0.5°latitude and longitude)that have various proportion of urban areas.Approximately 79.3%of these urban gridcells had increasing trends of annual GPP during 2000-2016.As urban area proportion(%)within individual urban gridcells increased,the means of annual GPP trends also increased.Our results suggested that for those urban gridcells,the negative effect of urban expansion(often measured by impervious surfaces)on GPP was to large degree compensated by increased vegetation within the gridcells,mostly driven by urban management and local climate and environment.Our findings on the continued increases of annual GPP in most of urban gridcells shed new insight on the importance of urban areas on terrestrial carbon cycle and the potential of urban management and local climate and environment on improving vegetation in urban areas. | Yaoping Cui Xiangming Xiao Jinwei Dong Yao Zhang Yuanwei Qin Russell BDoughty Xiaocui Wu Xiaoyan Liu Joanna Joiner Berrien Moore III | 2022 | Journal of Remote Sensing2022，，1： | 0 |
| 16 | Flow field and convective heat transfer of smallscale Taylor-Couette flow induced by end leakage显示文摘More and more researchers have paid attention to Taylor-Couette flow whose axial dimension is much larger than other dimensions.However,featured by the limited axial length of the bearing,its flow field and convective heat transfer between the rotator and the stator are highly conglutinated with the leakage at the end of the clearance.An investigation was conducted on the flow field and convective heat transfer of small-scale Taylor-Couette flow induced by end leakage through means of numerical simulation and experimental measurement.The static pressure and temperature of the stator were captured by a micromanometer and a time-resolved infrared camera,respectively.Large Eddy Simulation(LES)was performed to reveal the instantaneous and mean flow field of the shearing flow.Results show that the flow field and convective heat transfer are tightly associated with the presence of end leakage.As approaching the end of the clearance,the flow is dominated by the axial flow induced by the end leakage,and then a series of Taylor vortices gradually distorts and tilts as moving downstream.Along the angular direction,the maximum and minimum static pressures take place near minimum clearance height,respectively.The static pressure along the angular direction and the axial velocity near the minimum clearance height as well as the Nusselt number increase with increases of the rotational Reynolds number and the eccentricity ratio while decreasing with an increase of the dimensionless clearance height.Both natural convection by buoyancy and forced convection by the shearing flow play a significant role in convective heat transfer.Compared with classic Taylor-Couette flow,the occurrence of leakage decreases the maximum static pressure while increasing the minimum static pressure.The formation and evolution of the Taylor vortex are dominated by the axial flow. | Jingyang ZHANG Zhaokun MA Yuan LIU Guiping ZHU Yuanwei LYU | 2023 | Chinese Journal of Aeronautics2023，36，11： | 0 |
| 17 | Output regulation of nonaffine nonlinear systems using singular perturbation theory显示文摘A control synthesis method for output regulation based on singular perturbation theory combined with inverting design is considered for a class of nonaffine nonlinear systems.The resulting control signal is defined as a solution to 'fast' dynamics which inverts a series error model,whose state is exponentially stable.It is shown that,under sufficient conditions being consistent with the assumptions of singular perturbation theory,this problem is solvable with(ε) tracking error if and only if a set of first-order nonlinear partial differential equations are solvable.The control law can be easily constructed and the simulations show the feasibility and effectiveness of the controller. | Bo MENG Yuanwei JING, Xiaoping LIU | 2009 | 控制理论与应用(英文版)2009，7，2： | 0 |
| 18 | Atomic origin of spin-valve magnetoresistance at the SrRuO3 grain boundary显示文摘Defects exist ubiquitously in crystal materials, and usually exhibit a very different nature from the bulk matrix.Hence, their presence can have significant impacts on the properties of devices.Although it is well accepted that the properties of defects are determined by their unique atomic environments, the precise knowledge of such relationships is far from clear for most oxides because of the complexity of defects and difficulties in characterization.Here, we fabricate a 36.8°Sr RuO3 grain boundary of which the transport measurements show a spin-valve magnetoresistance.We identify its atomic arrangement, including oxygen,using scanning transmission electron microscopy and spectroscopy.Based on the as-obtained atomic structure, the density functional theory calculations suggest that the spin-valve magnetoresistance occurs because of dramatically reduced magnetic moments at the boundary.The ability to manipulate magnetic properties at the nanometer scale via defect control allows new strategies to design magnetic/electronic devices with low-dimensional magnetic order. | Xujing Li Li Yin Zhengxun Lai Mei Wu Yu Sheng Lei Zhang Yuanwei Sun Shulin Chen Xiaomei Li Jingmin Zhang Yuehui Li Kaihui Liu Kaiyou Wang Dapeng Yu Xuedong Bai Wenbo Mi Peng Gao | 2020 | National Science Review2020，7，4： | 0 |
| 19 | Design and performance analysis of tracking controller for uncertain nonlinear composite system using neural networks显示文摘Based on high order dyna mi c neural network,this paper presents the tracking problem for uncertain nonlinear composite system,which contain s external disturbance,whose nonlinear ities are assumed to be unknown.A smooth contr oller is designed to guarantee a uniform ultimate boundedness property for the tracking error and a ll other signals in the closed loop.Certain meas ures are utilized to test its performance.No a priori knowledge of an upper bound on the “ optimal' weight and modeling error is required;the weights of neural networks are updated on-line.N umerical simulations performed on a simple example i llustrate and clarify the approach. | Endong LIU Yuanwei JING Siying ZHANG | 2005 | 控制理论与应用(英文版)2005，3，2： | 0 |
| 20 | Simultaneously transmitting and reflecting(STAR)RISs for 6G:fundamentals,recent advances,and future directions显示文摘Simultaneously transmitting and reflecting reconfigurable intelligent surfaces(STAR-RISs)have been attracting significant attention in both academia and industry for their advantages of achieving 360°coverage and enhanced degrees-of-freedom.This article first identifies the fundamentals of STAR-RIS,by discussing the hardware models,channel models,and signal models.Then,three representative categorizing approaches for STAR-RISs are introduced from the phase-shift,directional,and energy consumption perspectives.Furthermore,the beamforming design of STAR-RISs is investigated for both independent and coupled phase-shift cases.As a recent advance,a general optimization framework,which has high compatibility and provable optimality regardless of the application scenarios,is proposed.As a further advance,several promising applications are discussed to demonstrate the potential benefits of applying STAR-RISs in sixth-generation wireless communication.Lastly,a few future directions and research opportunities are highlighted. | Yuanwei LIU Jiaqi XU Zhaolin WANG Xidong MU Jianhua ZHANG Ping ZHANG | 2023 | Frontiers of Information Technology & Electronic Engineering2023，24，12： | 0 |
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