|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Semi-tightly coupled integration of multi-GNSS PPP and S-VINS for precise positioning in GNSS-challenged environments显示文摘Because of its high-precision,low-cost and easy-operation,Precise Point Positioning(PPP)becomes a potential and attractive positioning technique that can be applied to self-driving cars and drones.However,the reliability and availability of PPP will be significantly degraded in the extremely difficult conditions where Global Navigation Satellite System(GNSS)signals are blocked frequently.Inertial Navigation System(INS)has been integrated with GNSS to ameliorate such situations in the last decades.Recently,the Visual-Inertial Navigation Systems(VINS)with favorable complementary characteristics is demonstrated to realize a more stable and accurate local position estimation than the INS-only.Nevertheless,the system still must rely on the global positions to eliminate the accumulated errors.In this contribution,we present a semi-tight coupling framework of multi-GNSS PPP and Stereo VINS(S-VINS),which achieves the bidirectional location transfer and sharing in two separate navigation systems.In our approach,the local positions,produced by S-VINS are integrated with multi-GNSS PPP through a graph-optimization based method.Furthermore,the accurate forecast positions with S-VINS are fed back to assist PPP in GNSS-challenged environments.The statistical analysis of a GNSS outage simulation test shows that the S-VINS mode can effectively suppress the degradation of positioning accuracy compared with the INS-only mode.We also carried out a vehicle-borne experiment collecting multi-sensor data in a GNSS-challenged environment.For the complex driving environment,the PPP positioning capability is significantly improved with the aiding of S-VINS.The 3D positioning accuracy is improved by 49.0%for Global Positioning System(GPS),40.3%for GPS+GLOANSS(Global Navigation Satellite System),45.6%for GPS+BDS(BeiDou navigation satellite System),and 51.2%for GPS+GLONASS+BDS.On this basis,the solution with the semi-tight coupling scheme of multi-GNSS PPP/S-VINS achieves the improvements of 41.8-60.6%in 3D position-ing accuracy compared with the multi-GNSS PPP/INS solutions. | Xingxing Li Xuanbin Wang Jianchi Liao Xin Li Shengyu Li Hongbo Lyu | 2021 | Satellite Navigation2021，2，1： | 10 |
| 2 | Effects of Constant versus Fluctuating Incubation Temperatures on Hatching Success, Incubation Length, and Hatchling Morphology in the Chinese Skink (Plestiodon chinensis)显示文摘We incubated eggs of Plestiodon chinensis under five constant(24, 26, 28, 30, and 32 °C) and one fluctuating thermal regimes to examine the effects of constant versus fluctuating incubation temperatures on hatching success, incubation length, and hatchling morphology. The duration of incubation varied considerably among the six temperature treatments, whereas hatching success did not. The mean incubation length decreased as temperature increased in a nonlinear way, and increased as the thermal variance increased. Incubation temperature affected the body size(linear length and mass) and shape of hatchlings, with eggs incubated at 26, 28, and 30 °C producing larger and heavier hatchlings than did those incubated at 24 °C, 32 °C, or fluctuating temperatures. Our results showed that exposure of P. chinensis eggs to extreme temperatures for brief periods of time did not increase embryonic mortality and, in the fluctuating-temperature treatment, the thermal variance affected hatchling morphology more evidently than the thermal mean. Our results highlight the importance of the thermal variance in affecting embryonic development and hatchling morphology, and add further evidence that temperatures within the range of 26-30 °C are optimal for P. chinensis embryos. | Wen SHEN Jianchi PEI Longhui LIN Xiang JI | 2017 | Asian Herpetological Research2017，18，4： | 5 |
| 3 | Research on the influence of the fly ash on the concrete carbonation显示文摘The influence of fly ash on the fresh properties, mechanical properties and carbonation properties were studied in this paper. The performance of a kind of curing agent which was applied to the hardened concrete surface was evaluated. Incorporating large volume of fly ash will risk the concrete carbonation. The curing agent could prevent the concrete carbonation, and the mechanism was explained. | Chen Ce Zhong Jianchi | 2011 | Engineering Sciences2011，9，2： | 2 |
| 4 | GIL:a tightly coupled GNSS PPP/INS/LiDAR method for precise vehicle navigation显示文摘Accurate positioning and navigation play a vital role in vehicle-related applications,such as autonomous driving and precision agriculture.With the rapid development of Global Navigation Satellite Systems(GNSS),Precise Point Positioning(PPP)technique,as a global positioning solution,has been widely applied due to its convenient operation.Nevertheless,the performance of PPP is severely affected by signal interference,especially in GNSS-challenged environments.Inertial Navigation System(INS)aided GNSS can significantly improve the continuity and accuracy of navigation in harsh environments,but suffers from degradation during GNSS outages.LiDAR(Laser Imaging,Detection,and Ranging)-Inertial Odometry(LIO),which has performed well in local navigation,can restrain the divergence of Inertial Measurement Units(IMU).However,in long-range navigation,error accumulation is inevitable if no external aids are applied.To improve vehicle navigation performance,we proposed a tightly coupled GNSS PPP/INS/LiDAR(GIL)integration method,which tightly integrates the raw measurements from multi-GNSS PPP,Micro-Electro-Mechanical System(MEMS)-IMU,and LiDAR to achieve high-accuracy and reliable navigation in urban environments.Several experiments were conducted to evaluate this method.The results indicate that in comparison with the multi-GNSS PPP/INS tightly coupled solution the positioning Root-Mean-Square Errors(RMSEs)of the proposed GIL method have the improvements of 63.0%,51.3%,and 62.2%in east,north,and vertical components,respectively.The GIL method can achieve decimeter-level positioning accuracy in GNSS partly-blocked environment(i.e.,the environment with GNSS signals partly-blocked)and meter-level positioning accuracy in GNSS difficult environment(i.e.,the environment with GNSS hardly used).Besides,the accuracy of velocity and attitude estimation can also be enhanced with the GIL method. | Xingxing Li Huidan Wang Shengyu Li Shaoquan Feng Xuanbin Wang Jianchi Liao | 2021 | Satellite Navigation2021，2，1： | 2 |
| 5 | Performance Analysis of Inter-Stage Leakage Flows at Rotating Conditions in an Axial Compressor显示文摘For the compressor with shrouded stator blades,the stator well is a rotor-stator space between the rotating drum and the stationary shroud.Due to the pressure difference,a reverse leakage flow would travel through the stator well and inject into the main flow path.Although,the labyrinth seal is commonly placed under the shroud,the rotation effect and seal clearance variation in actual operation process have great impact on the characteristics of this inter-stage leakage,as well as the compressor performance.In this paper,experiments were conducted at a compressor inter-stage seal test rig.The leakage flow rates,total temperatures and swirl ratios were obtained at different speeds and working clearances.The proportions of rotation effect and the clearance reduction effect were analyzed by data processing.Comparisons indicate that the working clearance and leakage flow reduce about 43%and 50%respectively,when the rotational speedω=8100 r/min.The proportion of reduction caused by the rotation effect is around 15%,while the influence of working clearance variation is much greater,accounting for about 35%.The windage heating coefficient and swirl ratio in the outlet cavity are almost in exponential relationship with the rotor speed.The increases in total temperature and swirl ratio generated by the rotation effect are found to be about 80%.In addition,the swirl and radial velocity profiles in the cavities were discussed by validated numerical simulations to reveal the typical flow characteristics.The data presented can provide guidance for better leakage conditions prediction as well as the inter-stage seal design enhancement. | KONG Xiaozhi LIU Yuxin LU Huawei TIAN Zhitao XIN Jianchi | 2020 | Journal of Thermal Science2020，29，6： | 2 |
| 6 | Software development of modeling assistant for continuous suspension bridges with multi-pylon显示文摘Building a reasonable and accurate finite element model is the first and critical step for structural analysis of complicated bridge. In this article, modeling assistant for continuous suspension with multi-pylon is developed based on .Net platform, with VB.Net, C# language and OpenGL graphic technique. With parameterized modeling method, finite element model of this kind of bridge can be built quickly and accurately, and multi-type element modeling with uniform parameters is realized. With advanced graphic technique, three-dimensional model graph can be real-timely previewed for intuitive data check. With an example of practice project, the accuracy and feasibility of this modeling method and practicality of this software are verified. | Zhong Jianchi Chen Ke Chen Yunhai Lu jianming | 2012 | Engineering Sciences2012，10，3： | 1 |
| 7 | Zebrafish Gli3 functions as both an activator and a repressor in Hedgehog signaling显示文摘 | Oksana V. Tyurina Burcu Guner Evgenya Popova Jianchi Feng Alexander F. Schier Jhumku D. Kohtz Rolf O. Karlstrom | 2004 | Developmental Biology2004，，2： | 1 |
| 8 | Computer-controlled automated jumbo drilling robot manipulator显示文摘 | Ho C Y Yao Jianchi | 1986 | International Journal nf Mining and Geological Engineering1986，，4： | 1 |
| 9 | Sexual Dimorphism, Female Reproductive Characteristics and Egg Incubation in an Oviparous Forest Skink(Sphenomorphus incognitus) from South China显示文摘We studied sexual dimorphism and female reproduction in an oviparous forest skink(Sphenomorphus incognitus)from South China.We incubated eggs under five thermal regimes(22,25,28,25±3 and 27±5°C)to examine the effects of constant versus fluctuating temperatures on incubation length and hatchling morphology.In our sample the largest male and female were 110 mm and 108 mm snout-vent length(SVL),respectively.Adult males and females did not differ in mean SVL;adult males were larger in head size(both length and width),longer in foreand hind-limb lengths and shorter in abdomen length than females of the same SVL.Accordingly,we conclude that S.incognitus is a sexually monomorphic species in terms of SVL but shows sexual dimorphism in head size,abdomen length and appendage length.Females laid a single clutch of 3-10 eggs per breeding season from early May to midAugust,with larger females generally laying more(but not always larger)eggs per clutch than did smaller ones.Embryonic stages at laying ranged from Dufaure and Hubert's(1961)stage 31 to 32,with a mean stage of 31.3.The positive relationship between clutch mass and female SVL was not significant.The offspring size-number trade-off does not exist in S.incognitus,as revealed by the fact that egg mass was independent of relative fecundity.Incubation length decreased as temperature increased,and stable temperatures resulted in delayed hatching.Hatchlings incubated under the five thermal regimes did not differ from each other in any examined trait,suggesting that S.incognitus is among oviparous reptilian species where incubation temperature has no role in modifying hatchling morphology as long as eggs are not exposed to extreme temperatures for prolonged periods of time. | Li MA Jianchi PEI Cuntong ZHOU Yu DU Xiang JI Wen SHEN | 2018 | Asian Herpetological Research2018，9，2： | 1 |
| 10 | Pulsed - field fingerprinting of Listeriae : Identification of genomic divisions for Listeria monocytogenes and their correlation with serovar显示文摘 | Roland Brosch Jianchi Chen John Bluchansky | 1994 | Appl Environ Microbiol1994，2584，： | 1 |
| 11 | Improved Outcome of Frozen-Thawed Blastocyst Transfer with Menezo’s two-step Thawing Compared to the Stepwise Thawing Protocol显示文摘 | Jianchi Ding Michelle Pry Nasir Rana W. Paul Dmowski | 2004 | Journal of Assisted Reproduction and Genetics2004，，6： | 1 |
| 12 | Pulsed-field fingerprinting of Listeriae: identification of genomic divisions for Listeria monocytogenes and their correlation with serovar 显示文摘 | ROLAND BROSCH JIANCHI CHEN JOHN LUCHANSKYI B | 1994 | Appl Environ Microbiol1994，60，7： | 1 |
| 13 | Taizhou Yangtze River Bridge——The first kilometer level three-pylon two-span suspension bridge in the world显示文摘Taizhou Bridge, located at the middle of Jiangsu Province, connecting Taizhou City and Zhenjiang City, started in Dec. 2007. The bridge is the first kilometer level three-pylon suspension bridge in the world, and it adopts longitudinal herringbone shape steel middle pylon for the first time in the world. The foundation of the middle tower is the deepest underwater caisson in soil on earth. A great many of technical innovations such as the design techniques of three-pylon suspension bridge,precisely locating and bottom-sealing techniques of the large scale caisson foundation, manufacturing, combination techniques of steel and concrete in the middle tower, welding of extra thick steel plate, manufacture and control techniques of abnormal sections of the middle tower and so on were introduced. | Zhong Jianchi | 2011 | Engineering Sciences2011，9，2： | 0 |
| 14 | Uplink Multiple Access Schemes for 5G:A Survey显示文摘In non-orthogonal multiple access(NMA) system, signal transmitter and receiver are jointly optimized, so that multiple layers ofdata from more than one user can be simultaneously delivered in the same resource. To meet the 5G requirements on the numberof connections and spectral efficiency, uplink NMA is becoming an important candidate technology and has been extensively stud-ied in 3GPP. A number of uplink NMA schemes from different industrial companies have been proposed in recent 3GPP meet-ings. In terms of their basic technique principles, this paper classifies these NMA schemes into three categories, namely: scram-bling based NMA schemes, interleaving based NMA schemes, and spreading based NMA schemes. Moreover, the key characteris-tics of these schemes are summarized, and the detailed introduction of each scheme is provided according to the comprehensivesurvey of the latest progress in 3GPP 5G standardization work. | YANG Shan CHEN Peng LIANG Lin ZHU Jianchi SHE Xiaoming | 2017 | ZTE Communications2017，15，B06： | 0 |
| 15 | New method for cotton fractional vegetation cover extraction based on UAV RGB images显示文摘As the key principle of precision farming,the distribution of fractional vegetation cover is the basis of crop management within the field serves.To estimate crop FVC rapidly at the farm scale,high temporal-spatial resolution imagery obtained by unmanned aerial vehicle(UAV)was adopted.To verify the application potential of consumer-grade UAV RGB imagery in estimated FVC,blue-green characteristic vegetation index(TBVI)and red-green vegetation index(TRVI)were proposed in this study according to the differences of the gray value among cotton vegetation,soil and shadow in the field.First,two new constructed indices and several published indices were used to extract visible light images and generate greyscale images for each of the visible light vegetation indices.Then,the thresholds of cotton vegetation and non-vegetation pixels were established based on the vegetation index threshold method which combines support vector machine classification and vegetation index.Finally,the accuracy difference in vegetation information extraction between the newly constructed and several published indices was compared.The results show that the accuracy of the information extracted by TRVI is higher than that of subdivision index of other visible light(FVC extraction precision in the first bud stage of cotton:R2=0.832,RMSE=2.307,nRMSE=4.405%;FVC extraction precision in the bud stage of cotton:R2=0.981,RMSE=1.393,nRMSE=1.984%;FVC extraction precision in the flowering stage of cotton:R2=0.893,RMSE=2.101,nRMSE=2.422%;FVC extraction precision in the boll stage of cotton:R2=0.958,RMSE=1.850,nRMSE=2.050%). | Huanbo Yang Yubin Lan Liqun Lu Daocai Gong Jianchi Miao Jing Zhao | 2022 | International Journal of Agricultural and Biological Engineering2022，15，4： | 0 |
| 16 | Intelligent 6G Wireless Network with Multi-Dimensional Information Perception显示文摘Intelligence and perception are two operative technologies in 6G scenarios.The intelligent wireless network and information perception require a deep fusion of artificial intelligence(AI)and wireless communications in 6G systems.Therefore,fusion is becoming a typical feature and key challenge of 6G wireless communication systems.In this paper,we focus on the critical issues and propose three application scenarios in 6G wireless systems.Specifically,we first discuss the fusion of AI and 6G networks for the enhancement of 5G-advanced technology and future wireless communication systems.Then,we introduce the wireless AI technology architecture with 6G multidimensional information perception,which includes the physical layer technology of multi-dimensional feature information perception,full spectrum fusion technology,and intelligent wireless resource management.The discussion of key technologies for intelligent 6G wireless network networks is expected to provide a guideline for future research. | YANG Bei LIANG Xin LIU Shengnan JIANG Zheng ZHU Jianchi SHE Xiaoming | 2023 | ZTE Communications2023，21，2： | 0 |
| 17 | Easy Network: The Way to Go for 5G显示文摘To satisfy the explosive growth of mobile data traffic and communication connections in the year 2020 and beyond, the 5th generation(5G) mobile network will have to support more access schemes, frequency bands and diversified scenarios compared with the existing networks. Throughout the development of communication systems, the diversified combination of different technologies always makes the network more and more 'heavy', e.g., heavy deployment, heavy investment, heavy operation and maintenance(O&M), which has brought great challenges to the network applications. Therefore, 5G system should be designed as an easy network, characterized by easy deployment, low investment, easy O&M and delightful experience. According to this discussion, this paper identifies several technical components which can make up an Easy Network for 5G air interface, and the details of the Easy Network features are analyzed. Our study aims to make efforts to promote a healthy and sustainable environment for 5G at the beginning of the system design. | LIU Yang SHE Xiaoming CHEN Peng ZHU Jianchi YANG Fengyi | 2015 | China Communications2015，12，S1： | 0 |
| 18 | Summer maize LAI retrieval based on multi-source remote sensing data显示文摘Leaf Area of Index(LAI)refers to half of the total leaf area of all crops per unit area.It is an important index to represent the photosynthetic capacity and biomass of crops.To obtain LAI conditions of summer maize in different growth stages quickly and accurately,further guiding field fertilization and irrigation.The Unmanned aerial vehicles(UAV)multispectral data,growing degree days,and canopy height model of 2020-2021 summer maize were used to carry out LAI inversion.The vegetation index was constructed by the ground hyperspectral data and multispectral data of the same range of bands.The correlation analysis was conducted to verify the accuracy of the multispectral data.To include many bands as possible,four vegetation indices which included R,G,B,and NIR bands were selected in this study to test the spectral accuracy.There were nine vegetation indices calculated with UAV multispectral data which were based on the red band and the near-infrared band.Through correlation analysis of LAI and the vegetation index,vegetation indices with a higher correlation to LAI were selected to construct the LAI inversion model.In addition,the Canopy Height Model(CHM)and Growing degree days(GDD)of summer maize were also calculated to build the LAI inversion model.The LAI inversion of summer maize was carried out based on multi-growth stages by using the general linear regression model(GLR),Multivariate nonlinear regression model(MNR),and the partial least squares regression(PLSR)models.R²and RMSE were used to assess the accuracy of the model.The results show that the correlation between UAV multispectral data and hyperspectral data was greater than 0.64,which was significant.The Wide Dynamic Range Vegetation Index(WDRVI),Normalized Difference Vegetation Index(NDVI),Ratio Vegetation Index(RVI),Plant Biochemical Index(PBI),Optimized Soil-Adjusted Vegetation Index(OSAVI),CHM and GDD have a higher correlation with LAI.By comparing the models constructed by the three methods,it was found that the PLSR has the best inversion effect.It was based on OSAVI,GDD,RVI,PBI,CHM,NDVI,and WDRVI,with the training model’s R²being 0.8663,the testing model’s R²being 0.7102,RMSE was 1.1755.This study showed that the LAI inversion model based on UAV multispectral vegetation index,GDD,and CHM improves the accuracy of LAI inversion effectively.That means the growing degree days and crop population structure change have influenced the change of maize LAI certainly,and this method can provide decision support for maize growth monitoring and field fertilization. | Fangjiang Pan Jinkai Guo Jianchi Miao Haiyu Xu Bingquan Tian Daocai Gong Jing Zhao Yubin Lan | 2023 | International Journal of Agricultural and Biological Engineering2023，16，2： | 0 |
| 19 | Progress and Achievements of Multi-sensor Fusion Navigation in China during 2019—2023显示文摘Global Navigation Satellite System(GNSS)can provide all-weather,all-time,high-precision positioning,navigation and timing services,which plays an important role in national security,national economy,public life and other aspects.However,in environments with limited satellite signals such as urban canyons,tunnels,and indoor spaces,it is difficult to provide accurate and reliable positioning services only by satellite navigation.Multi-source sensor integrated navigation can effectively overcome the limitations of single-sensor navigation through the fusion of different types of sensor data such as Inertial Measurement Unit(IMU),vision sensor,and LiDAR,and provide more accurate,stable and robust navigation information in complex environments.We summarizes the research status of multi-source sensor integrated navigation technology,and focuses on the representative innovations and applications of integrated navigation and positioning technology by major domestic scientific research institutions in China during 2019—2023. | Xingxing LI Xiaohong ZHANG Xiaoji NIU Jian WANG Ling PEI Fangwen YU Hongjuan ZHANG Cheng YANG Zhouzheng GAO Quan ZHANG Feng ZHU Weisong WEN Tuan LI Jianchi LIAO Xin LI | 2023 | Journal of Geodesy and Geoinformation Science2023，6，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员