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Positive health:An integrated quantitative approach in patients with chronic gastrointestinal and hepato-pancreatico-biliary disorders
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作者 Anja H W M Lemlijn-Slenter Karolina AP Wijnands +4 位作者 Gijs van der Hamsvoort Luuk P van Iperen Nico Wolter Angelique E de Rijk Ad AM Masclee 《World Journal of Gastroenterology》 SCIE CAS 2024年第28期3418-3427,共10页
BACKGROUND The concept of positive health(PH)supports an integrated approach for patients by taking into account six dimensions of health.This approach is especially relevant for patients with chronic disorders.Chroni... BACKGROUND The concept of positive health(PH)supports an integrated approach for patients by taking into account six dimensions of health.This approach is especially relevant for patients with chronic disorders.Chronic gastrointestinal and hepatopancreatico-biliary(GI-HPB)disorders are among the top-6 of the most prevalent chronically affected organ systems.The impact of chronic GI-HPB disorders on individuals may be disproportionally high because:(1)The affected organ system frequently contributes to a malnourished state;and(2)persons with chronic GIHPB disorders are often younger than persons with chronic diseases in other organ systems.AIM To describe and quantify the dimensions of PH in patients with chronic GI-HPB disorders.METHODS Prospective,observational questionnaire study performed between 2019 and 2021 in 235 patients with a chronic GIHPB disorder attending the Outpatient Department of the Maastricht University Medical Center.Validated questionnaires and data from patient files were used to quantify the six dimensions of PH.Internal consistency was tested with McDonald’s Omega.Zero-order Pearson correlations and t-tests were used to assess associations and differences.A P value<0.05 was considered significant.RESULTS The GI-HPB patients scored significantly worse in all dimensions of PH compared to control data or norm scores from the general population.Regarding quality of life,participation and daily functioning,GI-HPB patients scored in the same range as patients with chronic disorders in other organ systems,but depressive symptoms(in 35%)and malnutrition(in 45%)were more frequent in patients with chronic GI-HPB disorders.Intercorrelation scores between the six dimensions were only very weak to weak,forcing us to quantify each domain separately.CONCLUSION All six dimensions of PH are impaired in the GI-HPB patients.Malnutrition and depressive symptoms are more prevalent compared to patients with chronic disorders in other organ systems. 展开更多
关键词 positive health Chronic gut disorders Gastrointestinal disorders Hepato-pancreatico-biliary disorders integrated care
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Performance Trade-off for Integrated Communication and Data-Assisted Positioning in MIMO-OFDM System 被引量:1
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作者 Lincong Han Rongke Liu +3 位作者 Zijie Wang Qirui Liu Qian Zhu John S.Thompson 《China Communications》 SCIE CSCD 2022年第11期129-147,共19页
Communication and positioning,the two pillars of mobile communication systems,are currently being integrated together.The development of communication technologies is the driving force of the positioning progress.In t... Communication and positioning,the two pillars of mobile communication systems,are currently being integrated together.The development of communication technologies is the driving force of the positioning progress.In turn,the location information provided by positioning improves the communication performance in various ways.However,the competition of these two functions in terms of resource allocation is a critical issue hindering their integration.In this article,we investigate the trade-off for the integrated communication and data-assisted positioning in multiple-input multiple-output orthogonal frequency division multiplexing systems.A data-assisted positioning method is designed first,which uses both positioning reference signals(PRSs)and data signals for positioning.The positioning and communication performance are theoretically evaluated respectively,then combined to obtain an integrated performance metric.The trade-off is analyzed and the integrated performance is optimized considering the priority of different functions.Numerical simulations show that the data-assisted positioning can not only improve the positioning accuracy,but also reduce the PRS overhead.And the established integrated performance metric can identify the optimal performance and the corresponding resource allocation schemes. 展开更多
关键词 integrated communication and positioning MIMO OFDM non-data aided CRLB MMSE
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Fuzzy adaptive Kalman filter for indoor mobile target positioning with INS/WSN integrated method 被引量:10
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作者 杨海 李威 罗成名 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1324-1333,共10页
Pure inertial navigation system(INS) has divergent localization errors after a long time. In order to compensate the disadvantage, wireless sensor network(WSN) associated with the INS was applied to estimate the mobil... Pure inertial navigation system(INS) has divergent localization errors after a long time. In order to compensate the disadvantage, wireless sensor network(WSN) associated with the INS was applied to estimate the mobile target positioning. Taking traditional Kalman filter(KF) as the framework, the system equation of KF was established by the INS and the observation equation of position errors was built by the WSN. Meanwhile, the observation equation of velocity errors was established by the velocity difference between the INS and WSN, then the covariance matrix of Kalman filter measurement noise was adjusted with fuzzy inference system(FIS), and the fuzzy adaptive Kalman filter(FAKF) based on the INS/WSN was proposed. The simulation results show that the FAKF method has better accuracy and robustness than KF and EKF methods and shows good adaptive capacity with time-varying system noise. Finally, experimental results further prove that FAKF has the fast convergence error, in comparison with KF and EKF methods. 展开更多
关键词 inertial navigation system(INS) wireless sensor network(WSN) mobile target integrated positioning fuzzy adaptive Kalman filter
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Application of interacting multiple model in integrated positioning system of vehicle
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作者 WEI Wen jun GAO Xue ze +1 位作者 GE Li rain GAO Zhong jun 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第3期279-285,共7页
To solve low precision and poor stability of the extended Kalman filter (EKF) in the vehicle integrated positioning system owing to acceleration, deceleration and turning (hereinafter referred to as maneuvering) ,... To solve low precision and poor stability of the extended Kalman filter (EKF) in the vehicle integrated positioning system owing to acceleration, deceleration and turning (hereinafter referred to as maneuvering) , the paper presents an adaptive filter algorithm that combines interacting multiple model (IMM) and non linear Kalman filter. The algorithm describes the motion mode of vehicle by using three state spacemode]s. At first, the parallel filter of each model is realized by using multiple nonlinear filters. Then the weight integration of filtering result is carried out by using the model matching likelihood function so as to get the system positioning information. The method has advantages of nonlinear system filter and overcomes disadvantages of single model of filtering algorithm that has poor effects on positioning the maneuvering target. At last, the paper uses IMM and EKF methods to simulate the global positioning system (OPS)/inertial navigation system (INS)/dead reckoning (DR) integrated positioning system, respectively. The results indicate that the IMM algorithm is obviously superior to EKF filter used in the integrated positioning system at present. Moreover, it can greatly enhance the stability and positioning precision of integrated positioning system. 展开更多
关键词 VEHICLE integrated positioning system information fusion algorithm extended Kalman filter (KEF) interacting multiple model (IMM)
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Multi-modal Gesture Recognition using Integrated Model of Motion, Audio and Video 被引量:3
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作者 GOUTSU Yusuke KOBAYASHI Takaki +4 位作者 OBARA Junya KUSAJIMA Ikuo TAKEICHI Kazunari TAKANO Wataru NAKAMURA Yoshihiko 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第4期657-665,共9页
Gesture recognition is used in many practical applications such as human-robot interaction, medical rehabilitation and sign language. With increasing motion sensor development, multiple data sources have become availa... Gesture recognition is used in many practical applications such as human-robot interaction, medical rehabilitation and sign language. With increasing motion sensor development, multiple data sources have become available, which leads to the rise of multi-modal gesture recognition. Since our previous approach to gesture recognition depends on a unimodal system, it is difficult to classify similar motion patterns. In order to solve this problem, a novel approach which integrates motion, audio and video models is proposed by using dataset captured by Kinect. The proposed system can recognize observed gestures by using three models. Recognition results of three models are integrated by using the proposed framework and the output becomes the final result. The motion and audio models are learned by using Hidden Markov Model. Random Forest which is the video classifier is used to learn the video model. In the experiments to test the performances of the proposed system, the motion and audio models most suitable for gesture recognition are chosen by varying feature vectors and learning methods. Additionally, the unimodal and multi-modal models are compared with respect to recognition accuracy. All the experiments are conducted on dataset provided by the competition organizer of MMGRC, which is a workshop for Multi-Modal Gesture Recognition Challenge. The comparison results show that the multi-modal model composed of three models scores the highest recognition rate. This improvement of recognition accuracy means that the complementary relationship among three models improves the accuracy of gesture recognition. The proposed system provides the application technology to understand human actions of daily life more precisely. 展开更多
关键词 gesture recognition multi-modal integration hidden Markov model random forests
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Double Position Servo Synchronous Drive System Based on Cross-Coupling Integrated Feedforward Control for Broacher 被引量:2
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作者 Wenqi LU Kehui JI +3 位作者 Hanqing DONG Jianya ZHANG Quanwu WANG Liang GUO 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期272-285,共14页
Synchronization errors directly deteriorate the machining accuracy of metal parts and the existed method cannot keep high synchronization precision because of external disturbances. A new double position servo synchro... Synchronization errors directly deteriorate the machining accuracy of metal parts and the existed method cannot keep high synchronization precision because of external disturbances. A new double position servo synchronous driving scheme based on semi-closed-loop cross- coupling integrated feedforward control is proposed. The scheme comprises a position error cross-coupling feedfor-ward control and a load torque identification with feed- forward control. A digital integrated simulation system for the dual servo synchronous drive system is established. Using a 20 t servo broacher, performance analysis of the scheme is conducted based on this simulation system and the simulation results show that systems with traditional parallel or single control have problems when the work- table works with an unbalanced load. However, the system with proposed scheme shows good synchronous perfor- mance and positional accuracy. Broaching tests are performed and the experimental results show that the maximum dual axis synchronization error of the system is only 8μm during acceleration and deceleration processes and the error between the actual running position and the given position is almost zero. A double position servo synchronous driving scheme is presented based on crosscoupled integrated feedforward compensation control, which can improve the synchronization precision. 展开更多
关键词 Broacher Double drive system Cross coupling position servo synchronous integrated feedforward
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Coupled Dynamics and Integrated Control for Position and Attitude Motions of Spacecraft:A Survey 被引量:2
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作者 Feng Zhang Guangren Duan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第12期2187-2208,共22页
Inspired by the integrated guidance and control design for endo-atmospheric aircraft,the integrated position and attitude control of spacecraft has attracted increasing attention and gradually induced a wide variety o... Inspired by the integrated guidance and control design for endo-atmospheric aircraft,the integrated position and attitude control of spacecraft has attracted increasing attention and gradually induced a wide variety of study results in last over two decades,fully incorporating control requirements and actuator characteristics of space missions.This paper presents a novel and comprehensive survey to the coupled position and attitude motions of spacecraft from the perspective of dynamics and control.To this end,a systematic analysis is firstly conducted in details to show the position and attitude mutual couplings of spacecraft.Particularly,in terms of the time discrepancy between spacecraft position and attitude motions,space missions can be categorized into two types:space proximity operation and space orbital maneuver.Based on this classification,the studies on the coupled dynamic modeling and the integrated control design for position and attitude motions of spacecraft are sequentially summarized and analyzed.On the one hand,various coupled position and dynamic formulations of spacecraft based on various mathematical tools are reviewed and compared from five aspects,including mission applicability,modeling simplicity,physical clearance,information matching and expansibility.On the other hand,the development of the integrated position and attitude control of spacecraft is analyzed for two space missions,and especially,five distinctive development trends are captured for space operation missions.Finally,insightful prospects on future development of the integrated position and attitude control technology of spacecraft are proposed,pointing out current primary technical issues and possible feasible solutions. 展开更多
关键词 Coupled position and attitude dynamic modeling integrated position and attitude control position and attitude coupling analysis SPACECRAFT space missions
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IAE-adaptive Kalman filter for INS/GPS integrated navigation system 被引量:14
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作者 Bian Hongwei Jin Zhihua Tian Weifeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期502-508,共7页
A marine INS/GPS adaptive navigation system is presented. GPS with two antenna providing vessel' s altitude is selected as the auxiliary system fusing with INS to improve the performance of the hybrid system. The Kal... A marine INS/GPS adaptive navigation system is presented. GPS with two antenna providing vessel' s altitude is selected as the auxiliary system fusing with INS to improve the performance of the hybrid system. The Kalman filter is the most frequently used algorithm in the integrated navigation system, which is capable of estimating INS errors online based on the measured errors between INS and GPS. The standard Kalman filter (SKF) assumes that the statistics of the noise on each sensor are given. As long as the noise distributions do not change, the Kalman filter will give the optimal estimation. However GPS receiver will be disturbed easily and thus temporally changing measurement noise will join into the outputs of GPS, which will lead to performance degradation of the Kalman filter. Many researchers introduce fuzzy logic control method into innovation-based adaptive estimation adaptive Kalman filtering (IAE-AKF) algorithm, and accordingly propose various adaptive Kalman filters. However how to design the fuzzy logic controller is a very complicated problem still without a convincing solution. A novel IAE-AKF is proposed herein, which is based on the maximum likelihood criterion for the proper computation of the filter innovation covariance and hence of the filter gain. The approach is direct and simple without having to establish fuzzy inference rules. After having deduced the proposed IAEAKF algorithm theoretically in detail, the approach is tested by the simulation based on the system error model of the developed INS/GPS integrated marine navigation system. Simulation results show that the adaptive Kalman filter outperforms the SKF with higher accuracy, robustness and less computation. It is demonstra- ted that this proposed approach is a valid solution for the unknown changing measurement noise exited in the Kalman filter. 展开更多
关键词 inertial navigation system global positioning system integrated navigation system adaptive Kalman filter
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Existence of Positive Solutions for Systems of Second-order Nonlinear Singular Differential Equations with Integral Boundary Conditions on Infinite Interval 被引量:18
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作者 LI Yao-hong 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期55-64,共10页
By using cone theory and the MSnch fixed theorem combined with a monotone iterative technique, we investigate the existence of positive solutions for systems of second- order nonlinear singular differential equations ... By using cone theory and the MSnch fixed theorem combined with a monotone iterative technique, we investigate the existence of positive solutions for systems of second- order nonlinear singular differential equations with integral boundary conditions on infinite interval and establish the existence theorem of positive solutions and iterative sequence for approximating the positive solutions. The results in this paper improve some known results. 展开更多
关键词 boundary value problems positive solutions integral boundary conditions theMSnch fixed point theorem
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CLASSIFICATION OF POSITIVE SOLUTIONS FOR NONLINEAR DIFFERENTIAL AND INTEGRAL SYSTEMS WITH CRITICAL EXPONENTS 被引量:8
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作者 Wenxiong Chen Congming Li 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期949-960,共12页
We classify all positive solutions for the following integral system:{ui(x)=∫Rn1/│x-y│^n-α fi(u(y))dy,x∈R^n,i=1,…,m,0〈α〈n,and u(x)=(u1(x),u2(x)…,um(x)).Here fi(u), 1 ≤ i ≤m, monotone non... We classify all positive solutions for the following integral system:{ui(x)=∫Rn1/│x-y│^n-α fi(u(y))dy,x∈R^n,i=1,…,m,0〈α〈n,and u(x)=(u1(x),u2(x)…,um(x)).Here fi(u), 1 ≤ i ≤m, monotone nondecreasing are real-valued functions of homogeneous degree n+α/n-α and are monotone nondecreasing with respect to all the independent variables U1, u2, ..., urn.In the special case n ≥ 3 and α = 2. we show that the above system is equivalent to thefollowing elliptic PDE system:This system is closely related to the stationary SchrSdinger system with critical exponents for Bose-Einstein condensate 展开更多
关键词 integral and PDE systems positive solutions method of moving planes radial symmetry UNIQUENESS
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M3SC:A Generic Dataset for Mixed Multi-Modal(MMM)Sensing and Communication Integration 被引量:3
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作者 Xiang Cheng Ziwei Huang +6 位作者 Lu Bai Haotian Zhang Mingran Sun Boxun Liu Sijiang Li Jianan Zhang Minson Lee 《China Communications》 SCIE CSCD 2023年第11期13-29,共17页
The sixth generation(6G)of mobile communication system is witnessing a new paradigm shift,i.e.,integrated sensing-communication system.A comprehensive dataset is a prerequisite for 6G integrated sensing-communication ... The sixth generation(6G)of mobile communication system is witnessing a new paradigm shift,i.e.,integrated sensing-communication system.A comprehensive dataset is a prerequisite for 6G integrated sensing-communication research.This paper develops a novel simulation dataset,named M3SC,for mixed multi-modal(MMM)sensing-communication integration,and the generation framework of the M3SC dataset is further given.To obtain multimodal sensory data in physical space and communication data in electromagnetic space,we utilize Air-Sim and WaveFarer to collect multi-modal sensory data and exploit Wireless InSite to collect communication data.Furthermore,the in-depth integration and precise alignment of AirSim,WaveFarer,andWireless InSite are achieved.The M3SC dataset covers various weather conditions,multiplex frequency bands,and different times of the day.Currently,the M3SC dataset contains 1500 snapshots,including 80 RGB images,160 depth maps,80 LiDAR point clouds,256 sets of mmWave waveforms with 8 radar point clouds,and 72 channel impulse response(CIR)matrices per snapshot,thus totaling 120,000 RGB images,240,000 depth maps,120,000 LiDAR point clouds,384,000 sets of mmWave waveforms with 12,000 radar point clouds,and 108,000 CIR matrices.The data processing result presents the multi-modal sensory information and communication channel statistical properties.Finally,the MMM sensing-communication application,which can be supported by the M3SC dataset,is discussed. 展开更多
关键词 multi-modal sensing RAY-TRACING sensing-communication integration simulation dataset
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Clock-based RAIM method and its application in GPS receiver positioning 被引量:4
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作者 滕云龙 师奕兵 《Journal of Central South University》 SCIE EI CAS 2012年第6期1558-1563,共6页
Because the signals of global positioning system (GPS) satellites are susceptible to obstructions in urban environment with many high buildings around, the number of GPS useful satellites is usually less than six. I... Because the signals of global positioning system (GPS) satellites are susceptible to obstructions in urban environment with many high buildings around, the number of GPS useful satellites is usually less than six. In this case, the receiver autonomous integrity monitoring (RAIM) method earmot exclude faulty satellite. In order to improve the performance of RAIM method and obtain the reliable positioning results with five satellites, the series of receiver clock bias (RCB) is regarded as one useful satellite and used to aid RAIM method. From the point of nonlinear series, a grey-Markov model for predicting the RCB series based on grey theory and Markov chain is presented. And then the model is used for aiding RAIM method in order to exclude faulty satellite. Experimental results demonstrate that the prediction model is fit for predicting the RCB series, and with the clock-based RAIM method the faulty satellite can be correctly excluded and the positioning precision of GPS receiver can be improved for the case where there are only five useful satellites. 展开更多
关键词 positioning precision receiver autonomous integrity monitoring (RAIM) receiver clock bias (RCB) grey theory Markov chain
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Integrated modeling of spacecraft relative motion dynamics using dual quaternion 被引量:1
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作者 PENG Xuan SHI Xiaoping GONG Yupeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期367-377,共11页
To realize high accurate control of relative position and attitude between two spacecrafts, the coupling between position and attitude must be fully considered and a more precise model should be established. This pape... To realize high accurate control of relative position and attitude between two spacecrafts, the coupling between position and attitude must be fully considered and a more precise model should be established. This paper breaks the traditional divide and conquer idea, and uses a mathematical tool, namely dual quaternion to establish the integrated 6 degree-of-freedom(6-DOF) model of relative position and attitude, which describes the coupled relative motion in a compact and efficient form and needs less information of the target. Considering the complex operation rules and the unclarity of the current relative motion model in dual quaternion, necessary mathematical foundations are given at first, followed by clear and detailed modeling process and analysis. Finally a generalized proportion-derivative(PD) controller law is designed. The simulation results show that based on the integrated model established by dual quaternion, this control law can achieve a high control accuracy of relative motion. 展开更多
关键词 relative motion dual quaternion position and attitude coupling integrated modeling
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Multi-mode controller IC for soft-switched flyback converter with high efficiency over the entire load range 被引量:1
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作者 Hai CHEN Meng-lian ZHAO +1 位作者 Xiao-bo WU Xiao-lang YAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1411-1419,共9页
This paper presents a multi-mode control scheme for a soft-switched flyback converter to achieve high efficiency and excellent load regulation over the entire load range. At heavy load, critical conduction mode with v... This paper presents a multi-mode control scheme for a soft-switched flyback converter to achieve high efficiency and excellent load regulation over the entire load range. At heavy load, critical conduction mode with valley switching (CCMVS) is employed to realize soft switching so as to reduce turn-on loss of power switch as well as conducted electromagnetic interference (EMI). At light load, the converter operates in discontinuous conduction mode (DCM) with valley switching and adaptive off-time control (AOT) to limit the switching frequency range and maintain load regulation. At extremely light load or in standby mode, burst mode operation is adopted to provide low power consumption through reducing both switching frequency and static power dissipation of the controller. The multi-mode control is implemented by an oscillator whose pulse duration is adjusted by output feedback. An accurate valley switching control circuit guarantees the minimum turn-on voltage drop of power switch. The pro-totype of the controller IC was fabricated in a 1.5-μm BiCMOS process and applied to a 310 V/20 V, 90 W flyback DC/DC converter circuitry. Experimental results showed that all expected functions were realized successfully. The flyback converter achieved a high efficiency of over 80% from full load down to 2.5 W, with the maximum reaching 88.8%, while the total power consumption in standby mode was about 300 mW. 展开更多
关键词 integrated circuit multi-mode controller Soft-switched flyback converter Valley detection
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Research Status and Trends of Indoor Positioning and Navigation Technology in China 被引量:2
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作者 Baoguo YU Lu HUANG +3 位作者 Yachuan BAO Haonan JIA Shuang LI Chong CHEN 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第3期87-101,共15页
As an essential component of future comprehensive Positioning,Navigation,and Timing(PNT)system,indoor positioning technology has extensive application demands,making it a focal point of attention in both academia and ... As an essential component of future comprehensive Positioning,Navigation,and Timing(PNT)system,indoor positioning technology has extensive application demands,making it a focal point of attention in both academia and industry.This article comprehensively reviews the research status of indoor positioning technology in China,with a focus on highlighting representative achievements and application validations from major research institutions in recent years.It addresses the challenges and issues faced in promotion and application of large-scale,high-precision indoor positioning.Furthermore,a universal and seamless indoor-outdoor positioning system architecture is proposed,along with a technical roadmap and key technologies to achieve this architecture.Finally,an analysis and outlook on future technological trends are presented. 展开更多
关键词 indoor positioning location services integrated PNT
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Hybrid Kalman and unscented Kalman filters for INS/GPS integrated system considering constant lever arm effect 被引量:1
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作者 常国宾 柳明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期575-583,共9页
In inertial navigation system(INS) and global positioning system(GPS) integrated system, GPS antennas are usually not located at the same location as the inertial measurement unit(IMU) of the INS, so the lever arm eff... In inertial navigation system(INS) and global positioning system(GPS) integrated system, GPS antennas are usually not located at the same location as the inertial measurement unit(IMU) of the INS, so the lever arm effect exists, which makes the observation equation highly nonlinear. The INS/GPS integration with constant lever arm effect is studied. The position relation of IMU and GPS's antenna is represented in the earth centered earth fixed frame, while the velocity relation of these two systems is represented in local horizontal frame. Due to the small integration time interval of INS, i.e. 0.1 s in this work, the nonlinearity in the INS error equation is trivial, so the linear INS error model is constructed and addressed by Kalman filter's prediction step. On the other hand, the high nonlinearity in the observation equation due to lever arm effect is addressed by unscented Kalman filter's update step to attain higher accuracy and better applicability. Simulation is designed and the performance of the hybrid filter is validated. 展开更多
关键词 inertial navigation system global positioning system(GPS) integrated system lever arm effect Kalman filter unscented Kalman filter
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Multiple Positive Solutions to Singular Fractional Differential System with Riemann-Stieltjes Integral Boundary Condition
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作者 Zhang Hai-yan Li Yao-hong 《Communications in Mathematical Research》 CSCD 2019年第3期208-218,共11页
In this paper, we study a class of singular fractional differential system with Riemann-Stieltjes integral boundary condition by constructing a new cone and using Leggett-Williams fixed point theorem. The existence of... In this paper, we study a class of singular fractional differential system with Riemann-Stieltjes integral boundary condition by constructing a new cone and using Leggett-Williams fixed point theorem. The existence of multiple positive solutions is obtained. An example is presented to illustrate our main results. 展开更多
关键词 FRACTIONAL differential equation positive solution integral boundary condition fixed point THEOREM
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SOME PROPERTIES OF INTEGRATED BISEMIGROUPS
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作者 许跟起 冯德兴 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期50-60,共11页
Some properties of integrated bisemigroup S(t) of linear operators on a Banach space X are studied. The structure of the positive and negative subspaces and the operation of integrated bisemigroup on corresponding dif... Some properties of integrated bisemigroup S(t) of linear operators on a Banach space X are studied. The structure of the positive and negative subspaces and the operation of integrated bisemigroup on corresponding differentiable subspace C-n are established. respectively. The decomposition of the infinitesimal generator A of S(t) and other interested problems are also considered. As application, an abstract boundary value problem is discussed. 展开更多
关键词 integrated bisemigroup positive and negative subspace abstract differential equation boundary value problem
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Optimal predication of double-star position/SINS based on discrete integration
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作者 林雪原 何友 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第2期179-182,共4页
Aiming at Double-Star positioning system's shortcomings of delayed position information and easy exposition of the user as well as the error increase of the SINS with the accumulation of time, the integration of D... Aiming at Double-Star positioning system's shortcomings of delayed position information and easy exposition of the user as well as the error increase of the SINS with the accumulation of time, the integration of Double-Star positioning system and the SINS is one of the developing directions for an integrated navigation system. This paper puts forward an optimal predication method of Double-Star/SINS integrated system based on discrete integration, which can make use of the delayed position information of Double-Star positioning system to optimally predicate the integrated system, and then corrects the SINS. The experimental results show that this method can increase the user's concealment under the condition of assuring the system's accuracy. 展开更多
关键词 discrete integration optimal predication Double-Star positioning system SINS
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Optimal Filtering Correction forMarine Dynamical Positioning Control System
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作者 Evgeny Veremey Margarita Sotnikova 《Journal of Marine Science and Application》 CSCD 2016年第4期452-462,共11页
This paper focuses on the problem of control law optimization for marine vessels working in a dynamical positioning (DP) regime. The approach proposed here is based on the use of a special unified multipurpose contr... This paper focuses on the problem of control law optimization for marine vessels working in a dynamical positioning (DP) regime. The approach proposed here is based on the use of a special unified multipurpose control law structure constructed on the basis of nonlinear asymptotic observers, that allows the decoupling of a synthesis into simpler particular optimization problems. The primary reason for the observers is to restore deficient information concerning the unmeasured velocities of the vessel. Using a number of separate items in addition to the observers, it is possible to achieve desirable dynamical features of the closed loop connection. The most important feature is the so-called dynamical corrector, and this paper is therefore devoted to solving its optimal synthesis in marine vessels controlled by DP systems under the action of sea wave disturbances. The problem involves the need for minimal intensity of the control action determined by high frequency sea wave components. A specialized approach for designing the dynamical corrector is proposed and the applicability and effectiveness of the approach are illustrated using a practical example of underwater DP system synthesis. 展开更多
关键词 dynamical positioning control law OBSERVER stability filter external disturbances sea waves CORRECTOR integral action
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