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| 1 | Advances in communications using optical vortices显示文摘An optical vortex having an isolated point singularity is associated with the spatial structure of light waves.A polarization vortex(vector beam) with a polarization singularity has spatially variant polarizations. A phase vortex with phase singularity or screw dislocation has a spiral phase front. The optical vortex has recently gained increasing interest in optical trapping, optical tweezers, laser machining, microscopy, quantum information processing, and optical communications. In this paper, we review recent advances in optical communications using optical vortices. First, basic concepts of polarization/phase vortex modulation and multiplexing in communications and key techniques of polarization/phase vortex generation and(de)multiplexing are introduced. Second, free-space and fiber optical communications using optical vortex modulation and optical vortex multiplexing are presented. Finally, key challenges and perspectives of optical communications using optical vortices are discussed. It is expected that optical vortices exploiting the space physical dimension of light waves might find more interesting applications in optical communications and interconnects. | Jian Wang | 2016 | Photonics Research2016，4，5： | 43 |
| 2 | Rural vitalization in China:A perspective of land consolidation显示文摘The core objective of rural vitalization is to systemically establish a coupling pattern of various rural development elements including population,land and industry.As one of the prerequisites,land resources is required to be optimally allocated via land consolidation.Con seque ntly,la nd con solidati on con tributes greatly to population agglomeration,industrial developme nt and resources support under the con text of combati ng rural decline.Based on the key eleme nts affecting rural development,this paper elaborates the con no tation of rural vitalization and land consolidation in the new era as well as their relationships.Furthermore,the paper analyzes the alternative paths for achieving rural vitalization via land consolidation,and discusses the future directions of land consolidation and rural vitalization.The conclusions are drawn as follows:(1)To cope with the loss and decline of the intrinsic elements in rural areas,rural vitalization is a development strategy aimed at realizing economic,political,cultural and ecological rejuvenation in rural area by reshaping socio?economic morphology and spatial pattern in rural territory.(2)From the perspective of rural vitalization,land consolidation is endowed with new connotation,which should not only target at activating the key elements of rural development,but also place emphasis on coordimating material space and spirit core as well as integrating the restructuring of the physical space and the rural gov?ernance system.(3)Land consolidation should be compatible with regional natural conditions and the current stage of socio-economic development.According to the principle of regional planning and classification strategy,the appropriate models and paths should be adopted to promote the benign interactions of population,land and industry based on engineering techniques and ecological means.(4)Under the background of national strategy of rural vitaliza?tion,it is n ecessary to reshape the value orientati on of la nd con solidation based on a scie tific understanding of urban-rural relations and rural territorial functions,coordinate land consolidation planning and rural vitalization planning under the unified spatial planning system,and explore the new model combining land consolidation and multifunctional agriculture. | LONG Hualou ZHANG Yingnan TU Shuangshuang | 2019 | Journal of Geographical Sciences2019，29，4： | 33 |
| 3 | 基于EMD的振动信号去噪方法研究显示文摘煤矿机械在重载情况下运行,其振动信号往往具有非线性、不平稳等特性,其不仅带有大量设备运动状态的信息,同时也夹杂着大量的环境噪声,无法直接对其进行分析。而经验模式分解(EMD)在处理非线性、非平稳信号时具有一定优势,是一种自适应的信号处理方法。针对煤矿机械振动信号的特性,提出基于EMD的去噪方法,首先将振动信号进行EMD分解,得到各固有模态函数(IMF),然后计算各IMF与原始信号的相关系数,并将相关系统按照从小到大进行排序,通过相邻两个相关系数的差值最大,找到敏感IMF分量重构,实现非平稳信号的滤波,为机械设备后期故障诊断奠定了良好基础。并通过实验数据分析,验证了EMD方法对振动信号进行去噪的有效性及可行性。 | 马宏伟 张大伟 曹现刚 董明 李从会 | 2016 | 振动与冲击2016，35，22： | 28 |
| 4 | 三种高分辨率格点降水预报检验方法的对比显示文摘客观有效的评估高分辨率模式格点降水的预报能力,不仅是模式发展中的基础问题,而且直接关系到目前中国气象局主推的格点天气预报业务。以ECMWF(European Centre for Medium-Range Weather Forecasts)模式高分辨率降水格点预报资料、CMORPH(NOAA Climate Prediction Center Morphing Method)卫星与全国3×104个自动观测站的逐时降水量融合资料为基础,选择2015年6~8月55个降水个例,研究传统检验方法、面向对象MODE(Method for Object-based Diagnostic Evaluation)方法、以及邻域法在高分辨率格点降水预报检验中的适用性及优缺点,以期为高分辨率格点降水的预报性能评估提供参考。主要结论如下:(1)尽管点对点的传统方法在高分辨率格点降水检验中存在一定的局限,但传统方法能够在空间上表现高分辨率格点降水预报技巧的地域性差异,在时间上刻画预报的整体性能,对高分辨率格点预报性能评估仍然具有重要的适用价值;(2)邻域法的显著优点在于一方面能够通过变换邻域窗获得不同空间尺度上的传统预报技巧,另一方面独有的FSS(Fractions Skill Score)技巧评分能够表现预报相对于观测降水在格点数量上的比值,结合FSS和不同邻域窗上的传统技巧评分,可以判别在多大空间尺度上能够获得较好的预报技巧;(3)MODE方法在变换卷积半径的基础上提取降水对象,基于降水对象不仅能统计模式的传统技巧评分和预报性能的尺度变化,还可以表现降水对象的质心距离、轴角、面积、强度、综合收益、位移距离等多种属性,这些属性首先为用户提供了模式预报性能的多视角表现,其次从侧面定量描述了模式对天气系统发展快慢、槽脊强弱等预报误差,具有独特的优势,但如何应用对象属性来提高实际的预报能力还存在一些困难。 | 潘留杰 薛春芳 张宏芳 王建鹏 姚静 | 2017 | 气候与环境研究2017，22，1： | 25 |
| 5 | The 1997-1998 warm event in the South China Sea显示文摘A strong warm event happens during spring 1997 to spring 1999 in the South China Sea. Its intensity and duration show that it is the strongest event on the record over the past decades. It also corresponds with the severe flood over the valley of the Yangtze River and a couple of marine environmental events. This note addressed the evolution process by using several data sets, such as sea surface temperature, height and wind stress in addition to subsurface temperature. The onset of the warm event almost tele-connects with the El Nino event in the tropical Pacific Ocean. Summer monsoon is stronger and winter monsoon is weaker in 1997 so that there are persistent westerly anomalies in the South China Sea. During the development phase, the warm advection caused by southerly anomalies is the major factor while the adjustment of the thermocline is not obvious. Subsequently, the southerly anomalies decay and even northerly anomalies appear in the summer of 1998 resulting from the weaker than normal summer | WANG Dongxiao XIE Qiang DU Yan WANG Weiqiang CHEN Ju | 2002 | Chinese Science Bulletin2002，47，14： | 24 |
| 6 | Design Theory of Full Face Rock Tunnel Boring Machine Transition Cutter Edge Angle and Its Application显示文摘At present, the inner cutters of a full face rock tunnel boring machine (TBM) and transition cutter edge angles are designed on the basis of indentation test or linear grooving test. The inner and outer edge angles of disc cutters are characterized as symmetric to each other with respect to the cutter edge plane. This design has some practical defects, such as severe eccentric wear and tipping, etc. In this paper, the current design theory of disc cutter edge angle is analyzed, and the characteristics of the rock-breaking movement of disc cutters are studied. The researching results show that the rotational motion of disc cutters with the cutterhead gives rise to the difference between the interactions of inner rock and outer rock with the contact area of disc cutters, with shearing and extrusion on the inner rock and attrition on the outer rock. The wear of disc cutters at the contact area is unbalanced, among which the wear in the largest normal stress area is most apparent. Therefore, a three-dimensional model theory of rock breaking and an edge angle design theory of transition disc cutter are proposed to overcome the flaws of the currently used TBM cutter heads, such as short life span, camber wearing, tipping. And a corresponding equation is established. With reference to a specific construction case, the edge angle of the transition disc cutter has been designed based on the theory. The application of TBM in some practical project proves that the theory has obvious advantages in enhancing disc cutter life, decreasing replacement frequency, and making economic benefits. The proposed research provides a theoretical basis for the design of TBM three-dimensional disc cutters whose rock-breaking operation time can be effectively increased. | ZHANG Zhaohuang MENG Liang SUN Fei | 2013 | Chinese Journal of Mechanical Engineering2013，26，3： | 24 |
| 7 | Biological couplings: Function, characteristics and implementation mode显示文摘Through rigorous natural selection, biological organisms have evolved exceptional functions highly adaptable to their living environments. Biological organisms can achieve a variety of biological functions efficiently by using the synergic actions of two or more different parts of the body, or the coupling effects of multiple factors, and demonstrate optimal adaptations to the living environment. In this paper, the function, characteristics and types of biological couplings are analyzed, the implementation mechanism and mode of biological coupling functions are revealed from the bionic viewpoint. Finally, the technological prospects of the bionic implementation of biological coupling function are predicted. | REN LuQuan & LIANG YunHong Key Laboratory of Bionic Engineering of Ministry of Education, School of Biological and Agricultural Engineering, Jilin University, Changchun 130025, China | 2010 | Science China(Technological Sciences)2010，53，2： | 23 |
| 8 | 基于对象诊断的空间检验方法(MODE)显示文摘基于对象诊断的空间检验方法 MODE(Method for Object-Based Diagnostic Evaluation),通过在空间场中识别对象,计算对象的相似度,并最终形成两个场的综合相似度来实现对两个空间场的检验。相对于传统的点对点的检验方法,该方法综合考虑了空间位置、形状、面积等多种因素,并通过符合主观判断的模糊逻辑算法计算相似度,克服了数值预报传统检验方法对于空间位置的过度依赖以及TS评分中的'双重惩罚'等不足。个例研究表明该方法具有明显的优势,有较高的实际应用价值。 | 王国荣 陈敏 由凤春 郭锐 | 2014 | 气象科技2014，42，4： | 20 |
| 9 | 目标检验方法在高分辨率数值天气预报检验中的应用显示文摘基于高分辨率数值模式的特点,为了弥补传统站点对站点等检验方法的不足,采用基于目标诊断的空间检验方法 MODE,对上海快速更新同化系统预报的2014年3月19日强对流降水和冰雹雷达回波进行了客观检验。该方法通过在空间场中识别目标,综合考虑了空间位置、形状、面积等多种因素,采用模糊逻辑算法计算预报和观测目标的相似度。结果表明,MODE在高分辨率数值模式检验中比传统方法具有明显的优势,尤其针对雷达回波的检验有较高的实际应用价值。同时讨论了MODE方法卷积平滑半径参数的选取对高分辨模式检验结果的影响。 | 李佳 陈葆德 徐同 | 2016 | 沙漠与绿洲气象2016，10，5： | 19 |
| 10 | MARK XIIA IFF系统及其信号消息格式显示文摘Mark XIIA是美军和北约盟军统一研制的新型敌我识别系统,其中Mode 5 IFF是Mark XIIA的最重要部分。首先,分析了Mark XIIA Mode 5的性能特点,表明Mode 5不仅能完成基本的敌我识别功能,同时具有态势感知、选址询问、数据传输等功能;其次,对Mark XIIA系统的工作原理进行了分析,给出了系统工作原理框图;最后,叙述了Mark XIIA Mode 5的信号消息格式及处理流程,分析了其抗干扰性能。 | 邱宏坤 杨建波 毛虎 | 2010 | 电讯技术2010，50，6： | 16 |
| 11 | Assessment of bearing performance degradation via extension and EEMD combined approach显示文摘As a key component in rotating machinery, the operating reliability of bearing influences the performance and service life of the equipment directly. In order to describe bearing performance degradation(BPD) process effectively, an assessment approach combining extension and ensemble empirical mode decomposition(EEMD) was proposed. First, the extension was utilized to construct the matter-element of bearing operating state, and the energy moment of intrinsic mode functions(IMFs) was used as characteristic parameter of the matter-element. Then, to determine classical domains of characteristic parameters, the mathematical statistics method was adopted. Finally, the BPD was analyzed qualitatively and quantitatively according to the comprehensive correlation degree of bearing current operating state related to its healthy state. The analytic results of bearing test-rig show that the proposed method indicates the incipient fault approximately occurring in the 81 st hour, and the method also quantitatively presents the degree of BPD. By contrast, the BPD assessment based on time-domain features extraction method could not achieve the above two results effectively. | 刘玉梅 赵聪聪 熊明烨 赵颖慧 乔宁国 田广东 | 2017 | Journal of Central South University2017，24，5： | 16 |
| 12 | Passive Q-switching and Q-switched mode-locking operations of 2 μm Tm:CLNGG laser with MoS2 saturable absorber mirror显示文摘With MoS2 as saturable absorber, passive Q-switching and Q-switched mode-locking operations of a Tm-doped calcium lithium niobium gallium garnet(Tm:CLNGG) laser were experimentally demonstrated. The Q-switched laser emitted a maximum average output power of 62 mW and highest pulse energy of 0.72 μJ. Q-switched mode locking was also obtained in the experiment. The research results will open up applications of MoS2 at the mid-infrared wavelength. | L.C.Kong G.Q.Xie P.Yuan L.J.Qian S.X.Wang H.H.Yu H.J.Zhang | 2015 | Photonics Research2015，3，2： | 16 |
| 13 | Processes and modes of permafrost degradation on the Qinghai-Tibet Plateau显示文摘Climate warming must lead the mainly air temperature controlled permafrost to degrade.Based on the numerical simulation,the process of permafrost degradation can be divided into five stages,i.e.,starting stage,temperature rising stage,zero geothermal gradient stage,talic layers stage,and disappearing stage,according to the shape of ground temperature profile.Permafrost on the Qinghai-Tibet Plateau (QTP) is generally considered a relic from late Pleistocene,and has been degenerating as a whole during Holocene.According to spatial-temporal compensation,the present thermal state discrepancy of permafrost in different areas on the QTP may correspond with their degradation stages.On the QTP,permafrost in the high and middle mountains belongs to temperature rising stage,the permafrost thermal state is transiting from late rising temperature stage to zero geothermal gradient stage that is distributed in the middle-low-mountains.Permafrost that is in a zero gradient stage mainly appears in the high plateau and valley,whereas the transition from zero gradient stage to talic layers stage of permafrost is located in the vicinity of the lower limit of permafrost,and permafrost is disappearing from margin of perennially frozen ground.There are two modes of perennially frozen ground thawing,thawing from top to bottom and thawing from bottom to top respectively.During the temperature rising stage,when the heat flux in the perennially frozen soil layer is less than that in the unfrozen soil underlying frozen soil layer,the geothermal flux is partly used to thaw the base of permafrost,and permafrost thaws from bottom to top.With the decrease of thermal gradient in the perennially frozen ground,the heat that is used to thaw permafrost base increases,and geothermal heat will be entirely consumed to thaw the base of permafrost until the temperature gradient reaches zero thermal gradient state.On the other hand,the disappearance of permafrost may be delayed by 'thermal offset' and 'seasonal offset' effects in the upper of permafrost layer.When ground surface temperature rises to the level that can counteract the thermal offset effect,heat accumulation in the active layer would start,and the thickness of the active layer increases until a talic layer to appear.This process can be intensified by the 'seasonal anti-offset effect'. | WU JiChun,SHENG Yu,WU QingBai & WEN Zhi State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China | 2010 | Science China Earth Sciences2010，53，1： | 16 |
| 14 | Recent progress on ULF wave and its interactions with energetic particles in the inner magnetosphere显示文摘The global distribution properties of Ultra Low Frequency wave (ULF) in the inner magnetospgere and its interactions with energetic particles, such as the wave-particle resonance, modulation, and particle acceleration, are active topics in space physics research. These problems are fundamentally important issues to understand the energy transport from the solar wind into the magnetosphere. In this paper we briefly reviewed the recent research progress on ULF wave and its interactions with energetic particles in the inner magnetosphere; furthermore, we suggested some open questions for future study. | Theodore A. FRITZ | 2008 | Science China(Technological Sciences)2008，51，10： | 16 |
| 15 | 现代空袭作战模式研究显示文摘依据近期空袭作战的实际战例,以及空袭兵器的电子信息装备的发展水平,阐述现代航空航天兵器的空袭基本作战模式,以及现代空袭模式的可能发展变化。重点论述了空袭电子战作战模式。 | 李可达 | 2010 | 航天电子对抗2010，26，6： | 15 |
| 16 | Inversion for the sea bottom acoustic parameters by using the group time delays and amplitude of normal mode显示文摘The group time delays and amplitudes of the normal mode are derived using the normal mode filter. The sea bottom sound speed, density and attenuation are inversely deduced by matching the group time delays and the amplitude of the normal mode. A genetic algorithm (GA) is used for optimization search in the parameter space. The inverted attenuation has the nonlinear frequency relationship a = 0.29f1.91 dB/m (the unit of frequency is kHz) in the frequency range 200 - 500 Hz. The theoretical transmission loss calculated using the deduced parameters matches the experiment data very well. | LI Zhenglin YAN Jin LI Fenghua GUO Lianghao(National Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences Beijing 100080) | 2003 | Chinese Journal of Acoustics2003，22，2： | 15 |
| 17 | Stability analysis of large-scale stope using stage subsequent fillingmining method in Sijiaying iron mine显示文摘To improve mining production capacity, a stage subsequent filling mining(SSFM) method is employed for Sijiaying iron mine. The height of the stage stope is approximately 100 m. As there are farmlands and villages on the surface of the mine, the surface deformation should be controlled when the ore is mined out for the purpose of stope stability and minimizing surface subsidence. In this paper, according to the site-specificgeological conditions, the self-stability of the stagefi lling body was analyzed, and the failure mechanism of back filling body was defined. Thus the relationship between the exposed height of filling body and the required strength was obtained. Next, the stability of back filling body and the characteristics of surface subsidence due to mining of 450 m level were analyzed using physical modeling.Finally, a three-dimensional numerical model was established using FLAC3 D, with which the surface subsidence and the stability of stope were achieved. The results show that the stope basically remains stable during the two-step recovery process. The maximum magnitude of the incline is 10.99 mm/m, a little larger than the permissible value of 10 mm/m, and the horizontal deformation is 5.9 mm/m,approaching the critical value of 6.0 mm/m, suggesting that the mine design is feasible for safety mining. | Zhiqiang Yang Shuhua Zhai Qian Gao Maohui Li | 2015 | 岩石力学与工程学报2015，34，1： | 15 |
| 18 | 无陪护管理研究进展显示文摘无陪护管理模式(Without accompanying nursing management mode,WANMM)是与现代医学模式相适应的一种以患者为中心,注重生活护理及强化健康指导的优质护理服务模式。其在发达国家已十分普遍,也是衡量医院病房管理水平和服务质量的一项客观指标。近年来,我国也在一些省市尝试运行,现就国内外发展现况作一简单综述。 | 于利双 黄海玲 肖潇 张艳芳 王雅聪 赵有红 | 2017 | 护理实践与研究2017，14，2： | 15 |
| 19 | Development status of high power fiber lasers and their coherent beam combination显示文摘High-power fiber laser has been emerged great potential in a wide range of applications and becomes a robust candidate for high energy solid state laser system. To further increase the output brightness of single-channel fiber laser, high-brightness pump sources and high-power-handling passive components should be fabricated and utilized in the fiber laser systems, in addition to the advanced techniques for multiple nonlinear effects managements. The state-of-the-art high power fiber lasers are reviewed, in terms of narrow-linewidth fiber lasers, broadband fiber lasers and fiber lasers at 2 μm. Coherent beam combining is a promising technique to obtain higher output power while maintaining excellent beam quality simultaneously,which breaks through the bottlenecks of single-channel fiber laser. Based on a series of key techniques for coherent beam combining, high-power coherent beam combining of fiber lasers could be enabled with high combining efficiency. In this paper, we review the progress of high-power fiber lasers and their coherent beam combining in the recent decade, particularly the relevant work in our group. The future prospects of fiber lasers and coherent beam combining technique are also discussed. | Zejin LIU Xiaoxi JIN Rongtao SU Pengfei MA Pu ZHOU | 2019 | Science China(Information Sciences)2019，62，4： | 15 |
| 20 | 1.3 kW monolithic linearly polarized single-mode master oscillator power amplifier and strategies for mitigating mode instabilities显示文摘We report on the high-power amplification of a 1064 nm linearly polarized laser in an all-fiber polarizationmaintained master oscillator power amplifier,which can operate at an output power level of 1.3 kW.The beam quality(M^2) was measured to be <1.2 at full power operation.The polarization extinction rate of the fiber amplifier was measured to be above 94% before mode instabilities(MIs) set in,which reduced to about 90% after the onset of MI.The power scaling capability of strategies for suppressing MI is analyzed based on a semianalytical model,the theoretical results of which agree with the experimental results.It shows that mitigating MI by coiling the gain fiber is an effective and practical method in standard double-cladding large mode area fiber,and,by tight coiling of the gain fiber to the radius of 5.5 cm,the MI threshold can be increased to three times higher than that without coiling or loose coiling.Experimental studies have been carried out to verify the idea,which has proved that MI was suppressed successfully in the amplifier by proper coiling. | Rumao Tao Pengfei Ma Xiaolin Wang Pu Zhou Zejin Liu | 2015 | Photonics Research2015，3，3： | 15 |
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