|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Towards 6G wireless communication networks:vision,enabling technologies,and new paradigm shifts显示文摘The fifth generation(5G)wireless communication networks are being deployed worldwide from 2020 and more capabilities are in the process of being standardized,such as mass connectivity,ultra-reliability,and guaranteed low latency.However,5G will not meet all requirements of the future in 2030 and beyond,and sixth generation(6G)wireless communication networks are expected to provide global coverage,enhanced spectral/energy/cost efficiency,better intelligence level and security,etc.To meet these requirements,6G networks will rely on new enabling technologies,i.e.,air interface and transmission technologies and novel network architecture,such as waveform design,multiple access,channel coding schemes,multi-antenna technologies,network slicing,cell-free architecture,and cloud/fog/edge computing.Our vision on 6G is that it will have four new paradigm shifts.First,to satisfy the requirement of global coverage,6G will not be limited to terrestrial communication networks,which will need to be complemented with non-terrestrial networks such as satellite and unmanned aerial vehicle(UAV)communication networks,thus achieving a space-airground-sea integrated communication network.Second,all spectra will be fully explored to further increase data rates and connection density,including the sub-6GHz,millimeter wave(mmWave),terahertz(THz),and optical frequency bands.Third,facing the big datasets generated by the use of extremely heterogeneous networks,diverse communication scenarios,large numbers of antennas,wide bandwidths,and new service requirements,6G networks will enable a new range of smart applications with the aid of artificial intelligence(AI)and big data technologies.Fourth,network security will have to be strengthened when developing 6G networks.This article provides a comprehensive survey of recent advances and future trends in these four aspects.Clearly,6G with additional technical requirements beyond those of 5G will enable faster and further communications to the extent that the boundary between physical and cyber worlds disappears. | Xiaohu YOU Cheng-Xiang WANG Jie HUANG Xiqi GAO Zaichen ZHANG Mao WANG Yongming HUANG Chuan ZHANG Yanxiang JIANG Jiaheng WANG Min ZHU Bin SHENG Dongming WANG Zhiwen PAN Pengcheng ZHU Yang YANG Zening LIU Ping ZHANG Xiaofeng TAO Shaoqian LI Zhi CHEN Xinying MA Chih-Lin I Shuangfeng HAN Ke LI Chengkang PAN Zhimin ZHENG Lajos HANZO Xuemin(Sherman)SHEN Yingjie Jay GUO Zhiguo DING Harald HAAS Wen TONG Peiying ZHU Ganghua YANG Jun WANG Erik GLARSSON Hien Quoc NGO Wei HONG Haiming WANG Debin HOU Jixin CHEN Zhe CHEN Zhangcheng HAO Geoffrey Ye LI Rahim TAFAZOLLI Yue GAO HVincent POOR Gerhard P.FETTWEIS Ying-Chang LIANG | 2021 | Science China(Information Sciences)2021,64,1: | 122 |
| 2 | Paleogene-Neogene stratigraphic realm and sedimentary sequence of the Qinghai-Tibet Plateau and their response to uplift of the plateau显示文摘Based on the data of 1:250000 geological mapping completed by CGS and the previous literature of the Cenozoic strata, 98 remnant basins and 5 stratigraphic realms with 13 stratigraphic subrealms have been recognized on the Qinghai-Tibet Plateau and its adjacent area. Through the research of the types of remnant basins, tectonic setting, stratigraphic sequence and sedimentary characteristics, contact relationship between the strata, the formation time and evolution history of sediments, we divided the uplift process and sedimentary response of the Qinghai-Tibet Plateau into 3 stages and 8 sub-stages, namely, subduction-collision uplift stage (65-34 Ma) with three sub-stages, intercontinental convergence and compressive uplift stage (34-13 Ma) with three sub-stages, and intercontinental isostatic adjustment uplift stage (since 13 Ma) with two sub-stages. | ZHANG KeXin WANG GuoCan JI JunLiang LUO ManSheng KOU XiaoHu WANG YueMing XU YaDong CHEN FenNing CHEN RuiMing SONG BoWen ZHANG JianYu LIANG YinPing | 2010 | Science China Earth Sciences2010,53,9: | 49 |
| 3 | Cenozoic sedimentary records and geochronological constraints of differential uplift of the Qinghai-Tibet Plateau显示文摘Geological mapping data (1:250000) in the Qinghai-Tibet Plateau and its adjacent regions reveal the sediment sequences, distribution and tectonic evolution of the 92 Tertiary remnant basins. Southern Tibet and the Yecheng area in Xinjiang, located at southern and northwestern margins of the Qinghai-Tibet Plateau, respectively, were parts of the Neo-Tethys remnant sea in the Paleogene. In southern Tibet, both the subabyssal and abyssal sequences occur at the Gyangze, Saga, Guoyala, and Sangmai areas. The deep-water facies successions outcrop in the west, whereas the shallow-water facies sequences in the east, indicating the east to the west retreat of the Neo-Tethys Ocean. The retreat of the Neo-Tethys Ocean in the east was contributed to the earlier tectonic uplift of the eastern Qinghai-Tibet Plateau. The uplift process of the Plateau from the Late Cretaceous to Pliocene is described as follows: During the Late Cretaceous, tectonic uplift of the Qinghai-Tibet Plateau occurred in the northeastern part and the configuration of the Qinghai-Tibet Plateau was characterized by rise in the northeast and depression in the west. In the Paleocene-Eocene interval, the Tengchong-Baingoin and Kuyake-Golmud areas experienced local tectonic uplifting, the West Kunlun uplift zone broadened easterly, the Qilian uplift zone broadened southerly, and the Songpan-Garzê uplift zone shrank easterly. The Oligocene configuration of the Qinghai-Tibet Plateau was characterized by mountain chains rising along its margins and sedimentary basins in the central part because of tectonic uplifts of the Gangdisê and the Himalaya blocks. Meanwhile, the Kunlun-Altyn-Qilian uplift zones have also broadened southerly and northerly. In contrast, the great uplift zones of the Gangdisê, the Himalaya, the Karakorum, and the Kunlun blocks characterize the paleogeographic contours of the Qinghai-Tibet Plateau during the Miocene-Pliocene. Additionally, the thermochronological data on tectonic uplift events in southern Tibet, West Kunlun Mountains, Altyn Tagh, eastern Tibet, and western Sichuan all suggest that the most intense deformation occurred at 13-8 Ma and since 5 Ma, respectively, corresponding to two great uplift periods in Neogene. As a result, turnover of paleogeographic configuration of the Qinghai-Tibet Plateau occurred during the Neogene, experiencing a change from high contours in the east in the pre-Oligocene to high contours in the west at the end-Pliocene. The uplift of the Qinghai-Tibet Plateau during the Cenozoic was episodic, and the uplifts of various blocks within the Plateau were spatially and chronologically different. | ZHANG KeXin WANG GuoCan CAO Kai LIU Chao XIANG ShuYuan HONG HanLie KOU XiaoHu XU YaDong CHEN FenNing MENG YanNing CHEN RuiMing | 2008 | Science China Earth Sciences2008,51,11: | 31 |
| 4 | An overview of transmission theory and techniques of large-scale antenna systems for 5G wireless communications显示文摘To meet the future demand for huge traffic volume of wireless data service, the research on the fifth generation(5G) mobile communication systems has been undertaken in recent years. It is expected that the spectral and energy efficiencies in 5G mobile communication systems should be ten-fold higher than the ones in the fourth generation(4G) mobile communication systems. Therefore, it is important to further exploit the potential of spatial multiplexing of multiple antennas. In the last twenty years, multiple-input multiple-output(MIMO) antenna techniques have been considered as the key techniques to increase the capacity of wireless communication systems. When a large-scale antenna array(which is also called massive MIMO) is equipped in a base-station, or a large number of distributed antennas(which is also called large-scale distributed MIMO)are deployed, the spectral and energy efficiencies can be further improved by using spatial domain multiple access. This paper provides an overview of massive MIMO and large-scale distributed MIMO systems, including spectral efficiency analysis, channel state information(CSI) acquisition, wireless transmission technology, and resource allocation. | Dongming WANG Yu ZHANG Hao WEI Xiaohu YOU Xiqi GAO Jiangzhou WANG | 2016 | Science China(Information Sciences)2016,59,8: | 21 |
| 5 | Management of cytokine release syndrome related to CAR-T cell therapy显示文摘Chimeric antigen receptor T (CAR-T) cell therapy is a novel cellular immunotherapy that is widely used to treat hematological malignancies, including acute leukemia, lymphoma, and multiple myeloma. Despite its remarkable clinical effects, this therapy has side effects that cannot be underestimated. Cytokine release syndrome (CRS) is one of the most clinically important and potentially life-threatening toxicities. This syndrome is a systemic immune storm that involves the mass cytokines releasing by activated immune cells. This phenomenon causes multisystem damages and sometimes even death. In this study, we reported the management of a patient with recurrent and refractory multiple myeloma and three patients with acute lymphocytic leukemia who suffered CRS during CAR-T treatment. The early application of tocilizumab, an anti-IL-6 receptor antibody, according to toxicity grading and clinical manifestation is recommended especially for patients who suffer continuous hyperpyrexia, hypotensive shock, acute respiratory failure, and whose CRS toxicities deteriorated rapidly. Moreover, low doses of dexamethasone (5-10 mg/day) were used for refractory CRS not responding to tocilizumab. The effective management of the toxicities associated with CRS will bring additional survival opportunities and improve the quality of life for patients with cancer. | Hongli Chen Fangxia Wang Pengyu Zhang Yilin Zhang Yinxia Chen Xiaohu Fan Xingmei Cao Jie Liu Yun Yang Baiyan Wang Bo Lei Liufang Gu Ju Bai Lili Wei Ruili Zhang Qiuchuan Zhuang Wanggang Zhang Wanhong Zhao Aili He | 2019 | Frontiers of Medicine2019,13,5: | 21 |
| 6 | Magnetostratigraphy and Anisotropy of Magnetic Susceptibility of the Lulehe Formation in the Northeastern Qaidam Basin显示文摘The timing of onset of deposition of the Lulehe Formation is a significant factor in understanding the genesis of the Qaidam basin and the evolution of the Tibetan Plateau. Here, we describe a detailed magnetostratigraphic and magnetic fabric study of the middle and lower parts of the Lulehe Formation. A total of 234 samples were collected from 117 sites throughout a thickness of almost 460 m of fluvial and lacustrine deposits at the Xitieshan section in the northeastern Qaidam basin. Out of these sites, 94 sites yielded well-defined characteristic remanent magnetization components by stepwise thermal demagnetization and were used to establish the magnetostratigraphy of the studied section. Based on correlation with the geomagnetic polarity timescale, the studied section spans the period from 53.8 Ma to 50.7 Ma. Our results show a three-fold decrease in sedimentation rates as well as marked change in facies from braided river to delta and shore-shallow lake around 52.6 Ma, which suggests tectonic uplift of the northeastern Qaidam basin margin ridge was rapid at the onset of formation of the Qaidam basin and subsequently weakened after 52.6 Ma. The anisotropy of magnetic susceptibility results indicate that tectonic compression stress had reached the northeastern Tibetan Plateau by the early stages of Indo-Eurasian plate collision and that the direction of stress in the study area was NE-SW. Furthermore, a weakening of tectonic compression stress around 52.6 Ma is consistent with sedimentary records. The age of initial deposition of the Qaidam basin (around 53.8 Ma) was almost synchronous with that of the Qiangtang, Hoh Xil, Xining, and Lanzhou basins, which implies that stress was transferred rapidly through the Tibetan Plateau during or immediately after the onset of Indo-Eurasian collision. | KE Xue JI Junliang ZHANG Kexin KOU Xiaohu SONG Bowen WANG Chaowen | 2013 | Acta Geologica Sinica(English Edition)2013,87,2: | 18 |
| 7 | Application of novel force control strategies to enhance robotic abrasive belt grinding quality of aero-engine blades显示文摘Robotic belt grinding has emerged as a finishing process in recent years for machining components with high surface finish and flexibility.The surface machining consistency,however,is difficult to be guaranteed in such a process.To overcome this problem,a method of hybrid force-position control combined with PI/PD control is proposed to be applied in robotic abrasive belt grinding of complex geometries.Voltage signals are firstly obtained and transformed to force information with signal conditioning methods.Secondly,zero drift and gravity compensation algorithms are presented to calibrate the F/T transducer which is installed on the robot end-effector.Next,a force control strategy combining hybrid force-position control with PI/PD control is introduced to be employed in robotic abrasive belt grinding operations where the force control law is applied to the Z direction of the tool frame and the positon control law is used in the X direction of the tool frame.Then,the accuracy of the F/T transducer and the robotic force control system is analyzed to ensure the stability and reliability of force control in the robotic grinding process.Finally,two typical cases on robotic belt grinding of a test workpiece and an aero-engine blade are conducted to validate the practicality and effectiveness of the force control technology proposed. | Xiaohu XU Dahu ZHU Haiyang ZHANG Sijie YAN Han DING | 2019 | Chinese Journal of Aeronautics2019,32,10: | 16 |
| 8 | Radio Propagation and Wireless Coverage of LSAA-Based 5G Millimeter-Wave Mobile Communication Systems显示文摘Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell radii and complicated network architectures. A coverage extension scheme using large-scale antenna arrays(LSAAs) has been suggested and theoretically proven to be cost-efficient in combination with ultradense small cell networks. To analyze and optimize the LSAA-based network deployments, a comprehensive survey of recent advances in statistical mmWave channel modeling is first presented in terms of channel parameter estimation, large-scale path loss models, and small-scale cluster models. Next, the measurement and modeling results at two 5G candidate mmWave bands(e.g., 28 GHz and 39 GHz) are reviewed and compared in several outdoor scenarios of interest, where the propagation characteristics make crucial contributions to wireless network designs. Finally, the coverage behaviors of systems employing a large number of antenna arrays are discussed, as well as some implications on future mmWave cellular network designs. | Haiming Wang Peize Zhang Jing Li Xiaohu You | 2019 | China Communications2019,16,5: | 12 |
| 9 | Preliminary Experimental Investigation on MHD Power Generation Using Seeded Supersonic Argon Flow as Working Fluid显示文摘这篇论文在 magnetohydrodynamic (MHD ) 上论述初步的试验性的调查把播种的超声的氩流动用作工作液体的发电。氦和氩被用作司机并且在一条吃惊隧道分别地驾驶气体。平衡接触表面操作模式被用来获得高温度气体,并且传导性被增加种子 K2CO3 粉末进驾驶的节获得。在嘴入口总数压力的条件下面是 0.32 MPa,全部的温度 6 504 K,磁场密度大约 0.5 T 和嘴插头速度 1 959 m/s,正式就职电压和分割 MHD 发电隧道的电线走火电流被测量,并且试验性的结果同意理论计算;平均传导性是从电压和电流的特征计算的大约 20 S/m。当负担因素是 0.5 时, MHD 发电隧道的最大的力量密度到达 4.797 1 MW/m3,和最大的热含量抽取率是 0.34% 。最后,为煤气的州的参数的间接测试的原则和方法被导出并且分析。 | LI Yiwen LI Yinghong LU Haoyu ZHU Tao ZHANG Bailing CHEN Feng ZHAO Xiaohu | 2011 | Chinese Journal of Aeronautics2011,24,6: | 11 |
| 10 | New method for camera pose estimation based on line correspondence显示文摘The key technology of the measuring method of pose shaking of unstable platform based on CCD lies in the camera pose estimation.A new method for camera pose estimation based on line correspondence is put forward in this paper.First,two appropriate lines are selected in the space to establish a local coordinate system,the remaining lines form three-line sets with these two lines respectively and then the angle depth of the lines of the local coordinate system can be obtained by using the linearity of interpretation plane;then the invariance of included angle between spatial coordinate system and camera coordinate system during rigid transformation is used to establish a constraint equation set of angle depth of three lines similar to traditional P3P,and the corresponding angle depth of the third line in the set can be obtained linearly by variable substitution;finally,the rotation matrix can be expressed with quaternion and the pose parameters of camera in the space can be calculated by singular value decomposition(SVD).The static experiment and dynamic experiment verify the accuracy and stability of the algorithm and that the camera pose shocking is within 1°and the 3σ error is superior to 0.3′.The method in this paper can be directly used in the micro-vibration measurement of experimental platform and robot navigation and other fields and is of important theoretical significance and engineering application prospect. | LIU JinBo ZHANG XiaoHu LIU HaiBo YUAN Yun ZHU ZhaoKun YU QiFeng | 2013 | Science China(Technological Sciences)2013,56,11: | 11 |
| 11 | AI for 5G: research directions and paradigms显示文摘Wireless communication technologies such as fifth generation mobile networks(5 G) will not only provide an increase of 1000 times in Internet traffic in the next decade but will also offer the underlying technologies to entire industries to support Internet of things(IOT) technologies. Compared to existing mobile communication techniques, 5 G has more varied applications and its corresponding system design is more complicated. The resurgence of artificial intelligence(AI) techniques offers an alternative option that is possibly superior to traditional ideas and performance. Typical and potential research directions related to the promising contributions that can be achieved through AI must be identified, evaluated, and investigated.To this end, this study provides an overview that first combs through several promising research directions in AI for 5 G technologies based on an understanding of the key technologies in 5 G. In addition, the study focuses on providing design paradigms including 5 G network optimization, optimal resource allocation, 5 G physical layer unified acceleration, end-to-end physical layer joint optimization, and so on. | Xiaohu YOU Chuan ZHANG Xiaosi TAN Shi JIN Hequan WU | 2019 | Science China(Information Sciences)2019,62,2: | 10 |
| 12 | Monocular trajectory intersection method for 3D motion measurement of a point target显示文摘This article proposes a monocular trajectory intersection method,a videometrics measurement with a mature theoretical system to solve the 3D motion parameters of a point target.It determines the target’s motion parameters including its 3D trajectory and velocity by intersecting the parametric trajectory of a motion target and series of sight-rays by which a motion camera observes the target,in contrast with the regular intersection method for 3D measurement by which the sight-rays intersect at one point.The method offers an approach to overcome the technical failure of traditional monocular measurements for the 3D motion of a point target and thus extends the application fields of photogrammetry and computer vision.Wide application is expected in passive observations of motion targets on various mobile beds. | YU QiFeng SHANG Yang ZHOU Jian ZHANG XiaoHu LI LiChun | 2009 | Science China(Technological Sciences)2009,52,12: | 10 |
| 13 | Soil Microbial Population Dynamics along a Chronosequence of Moist Evergreen Broad-leaved Forest Succession in Southwestern China显示文摘Little is known about whether soil microbial population dynamics are correlated with forest succession.To test the hypotheses that(1) soil microbial composition changes over successional stages,and(2) soil microbial diversity is positively correlated with plant species diversity,we determined the soil microbial populations,community composition,and microflora diversity in evergreen broad-leaved forests along a chronosequence of vegetation succession from 5 to 300 years in southwestern China.The soil microbial community was mainly composed of bacteria(87.1-98.7% of the total microorganisms and 10 genera identified),fungi(0.3-4.0%,7 genera),and actinomycetes(2.1-9.1%,8 species and 1 genus).There were significant differences in soil microbial populations among different successional stages and within the four seasons.The seasonal variations of the soil microbial community may be associated with the seasonal changes in environmental conditions.The changes in soil microbial diversity(Shannon-Wiener index) with successional time followed one-humped,convex curves peaked at-100 years since restoration,which is identical with the trends of the aboveground plant diversity.Higher plant diversity resulting in enhanced nutrient flow and root exudation may contribute to positive relationships between the soil microbial diversity and plant diversity.Hence,decreases in soil microbial diversity in the late-successional stages appear to be related to the net loss in species richness that occurs after 100 years since restoration.Our findings confirm the intermediate disturbance hypothesis that suggests diversity peaks at midsuccessional stages. | ZHU Wanze CAI Xiaohu LIU Xingliang WANG Jinxi CHENG Song ZHANG Xiuyan LI Dengyu LI Maihe | 2010 | Journal of Mountain Science2010,7,4: | 8 |
| 14 | A new process to improve short-chain fatty acids and bio-methane generation from waste activated sludge显示文摘As an important intermediate product, short-chain fatty acids(SCFAs) can be generated after hydrolysis and acidification from waste activated sludge, and then can be transformed to methane during anaerobic digestion process. In order to obtain more SCFA and methane,most studies in literatures were centered on enhancing the hydrolysis of sludge anaerobic digestion which was proved as un-efficient. Though the alkaline pretreatment in our previous study increased both the hydrolysis and acidification processes, it had a vast chemical cost which was considered uneconomical. In this paper, a low energy consumption pretreatment method, i.e. enhanced the whole three stages of the anaerobic fermentation processes at the same time, was reported, by which hydrolysis and acidification were both enhanced, and the SCFA and methane generation can be significantly improved with a small quantity of chemical input. Firstly, the effect of different pretreated temperatures and pretreatment time on sludge hydrolyzation was compared. It was found that sludge pretreated at 100°C for 60 min can achieve the maximal hydrolyzation. Further, effects of different initial p Hs on acidification of the thermal pretreated sludge were investigated and the highest SCFA was observed at initial p H 9.0with fermentation time of 6 d, the production of which was 348.63 mg COD/g VSS(6.8 times higher than the blank test) and the acetic acid was dominant acid. Then, the mechanisms for this new pretreatment significantly improving SCFA production were discussed. Finally,the effect of this low energy consumption pretreatment on methane generation was investigated. | Bin Dong Peng Gao Dong Zhang Yinguang Chen Lingling Dai Xiaohu Dai | 2016 | Journal of Environmental Sciences2016,28,5: | 7 |
| 15 | Human infection with a further evolved avian H9N2 influenza A virus in Sichuan, China显示文摘Dear Editor,Avian influenza A (H9N2) virus plays a crucial role in interspecies transmission between animals and humans due to its wide host range, adaptation in mammals and the diversified gene reassortments. Since 1990s, two lineages of H9N2 virus, A/Duck/HK/Y280/97 (Y280-like)and A/Quail/HK/G1/97 (G1) have established in domestic poultry in China and are now widespread in the | Jianan Xu Shuang Li Yong Yang Bing Liu Huiping Yang Tiansu Li Lin Zhang Wei Li Xiaohu Luo Liquan Zhang Ming Pan | 2018 | Science China(Life Sciences)2018,61,5: | 7 |
| 16 | Design and Analysis of Gecko-like Robot显示文摘Gecko-like robot(Geckobot),an important branch of bionic robotics,is a robot that simulates gecko's capacity to climb walls and ceilings.The work environment of the traditional wall-climbing robot is greatly limited as the moving structure and adsorption principle of the robot have nothing to do with the real gecko.However,the adsorption principle and moving mode of the real gecko can provide a new way to break through the restrictions of the traditional wall-climbing robot.Inspired by the moving mechanism of geckos, this paper develops the Geckobot with motile body.Two types of Geckobots are addressed:one with compliant flat bar as the body,and the other with prismatic joint as the body.The compliant body not only resembles the moving mode of the real gecko body,but also simplifies the Geckobot's structure.The prismatic joint body is used to adapt the change of body length in ground-to-wall transition. The gait planning on the plane and the transition between perpendicular intersectional planes is discussed,with an emphasis on the analysis of the kinematics degree of freedom(DOF) and body posture.Central pattern generator(CPG) neural network is realized in LabVIEW and utilized to control Geckobot's movement.The CPG scheme in Lab VIEW is given,and how CPG is used to control Geckobot to turn or move forward is explored.Simulations are conducted in ADAMS to verify the feasibility of the structure design and gait planning and to acquire some parameters for practical Geckobot development.The experiment with Geckobot-Ⅰand Geckobot-Ⅱon their crawling capacity on the plane and the ground-to-wall transition finds that the robot can complete the crawling movement and ground-to-wall transition,verifying the feasibility of the structure design,gait planning and the CPG motion control.The Geckobot structure design approach,gait planning and the CPG motion control presented would be useful for the research on wall-climbing robots. | MENG Cai WANG Tianmiao GUAN Shengguo ZHANG Long WANG Jing LI Xiaohu | 2011 | Chinese Journal of Mechanical Engineering2011,24,2: | 6 |
| 17 | Videometric research on deformation measurement of large-scale wind turbine blades显示文摘Utilization of wind energy is a promising way to generate power,and wind turbine blades play a key role in collecting the wind energy effectively.This paper attempts to measure the deformation parameter of wind turbine blades in mechanics experiments using a videometric method. In view that the blades experience small buckling deformation and large integral deformation simultaneously, we proposed a parallel network measurement(PNM) method including the key techniques such as camera network construction,c... | Xiangyi Sun,Yun Yuan,~(a))Zhaokun Zhu,Xiaohu Zhang,and Qifeng Yu College of Aerospace and Materials Engineering,National University of Defense Technology,Changsha 410073, Hunan,China | 2011 | Theoretical & Applied Mechanics Letters2011,1,1: | 5 |
| 18 | Airport automatic detection in large space-borne SAR imagery显示文摘A method to detect airports in large space-borne synthetic aperture radar(SAR) imagery is studied.First,the large SAR imagery is segmented according to amplitude characteristics using maximum a posteriori(MAP) estimator based on the heavytailed Rayleigh model.The attention is then paid on the object of interest(OOI) extracted from the large images.The minimumarea enclosing rectangle(MER) of OOI is created via a rotating calipers algorithm.The projection histogram(PH) of MER for OOI is then computed and the scale and rotation invariant feature for OOI are extracted from the statistical characteristics of PH.A support vector machine(SVM) classifier is trained using those feature parameters and the airport is detected by the SVM classifier and Hough transform.The application in space-borne SAR images demonstrates the effectiveness of the proposed method. | Shaoming Zhang Yi Lin Xiaohu Zhang Yingying Chen | 2010 | Journal of Systems Engineering and Electronics2010,21,3: | 5 |
| 19 | Plant crop remains from the outer burial pit of the Han Yangling Mausoleum and their significance to Early Western Han agriculture显示文摘A large amount of carbonized plant remains were discovered in one of the outer burial pits of the Han Yangling Mausoleum, which was built more than 2000 years ago for the Jing Emperor, Liu, Qi (188―141 cal a BC), the fourth emperor of the Western Han Dynasty. The remains are identified by phytolith analysis and macrofossil morphological features. Seeds from foxtail millet (Setaria italica), broomcorn millet (Panicum miliaceum), rice (Oryza sativa) and chenopod (possible Chenopodium giganteum) are identified, suggesting that these four crops might have been the staple plant foods in the capital area (Guanzhong area), Shaanxi Province during the Early Western Han Dynasty. Chenopods were often considered as weeds since they have only been rarely found as carbonized seeds in prehistoric sites. This is the first time such a large amount of seeds has been found at a site, which provides strong material evidence for chenopod cultivation with a long history in China. Wheat was thought to be promoted and popularized in the Guanzhong area since the Wu Emporor, Liu, Che (156―87 cal a BC), the fifth emperor of the Western Han Dynasty. No wheat was found at this site, which supports the historical document record that wheat was still secondary in the diet and agrarian economy before the Wu Emperor's reign. | YANG XiaoYan LIU ChangJiang ZHANG JianPing YANG WuZhan ZHANG XiaoHu LV HouYuan | 2009 | Chinese Science Bulletin2009,54,10: | 5 |
| 20 | Correction method for non-landing measuring of vehicle-mounted theodolite based on static datum conversion显示文摘During the non-landing measuring of vehicle mounted theodolite, especially under high-speed tracking measurement, the misalignment of theodolite's center of mass and spindle etc. will cause high-frequency vibration of theodolite platform, increase the observation error of targets and even unbelievable results. In this paper, a correction method of non-landing measuring of theodolite based on static datum conversion is presented, which can effectively improve the observation accuracy of theodolite. The CCD camera is fixed to the theodolite platform to calculate the gesture shaking quantity of theodolite platform in geodetic coordinate system through the real time imaging of static datum. The observation results of theodolite are corrected by using such shaking quantity. The experiment shows that the correction accuracy exceeds 10 s of arc. The intrinsic parameter calibration technology of camera based on stellar angular distance and absolute conic put forward in this paper can prevent the estimated error of extrinsic parameters influencing the intrinsic parameter calibration and improve the intrinsic parameter calibration accuracy; the static datum conversion technology can reduce the influence of installation error of camera and theodolite platform on gesture measuring of the platform. The simulation experiment shows that when the shaking range of the platform is less than 30 min of arc, the influence of the three-axis installation error of camera within 3deg on the accuracy of correction results is less than 8 s of arc. The method in this paper can be extended to and used in the field of gesture shaking measuring and micro-structure deformation of various unstable platforms, therefore it is of important theoretical research significance and has wide engineering application prospect. | LIU JinBo ZHANG XiaoHu LIU HaiBo YUAN Yun ZHU ZhaoKun YU QiFeng | 2013 | Science China(Technological Sciences)2013,56,9: | 5 |