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The Prevalence of Overweight/Obesity and Related Comorbidities among HIV-Positive and HIV-Negative Patients Attending the Same Clinics in Gaborone, Botswana
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作者 Jose Gaby Tshikuka Matshwenyego Boitshwarelo +3 位作者 Shimeles Genna Hamda Roy Tapera Ngoyi Kashiba Zacharie Bukonda Marie Esako Onokoko 《Advances in Infectious Diseases》 CAS 2024年第3期523-540,共18页
Context: Antiretroviral therapy (ART) helps restore the health status of people living with HIV (PLHIV). Likewise, it increases the risk of overweight/obesity and related comorbidities among the recipients. In countri... Context: Antiretroviral therapy (ART) helps restore the health status of people living with HIV (PLHIV). Likewise, it increases the risk of overweight/obesity and related comorbidities among the recipients. In countries like Botswana where ±84% of PLHIV is on ART, the paucity of data comparing overweight/obesity between HIV-positive on ART and HIV-negative patients may impede clinical and policy decision-making. This study sought to estimate and compare: i) the prevalence of overweight/obesity between HIV-positive on ART and HIV-negative patients;ii) the prevalence of hypertension (HTN), diabetes mellitus (DM)/coronary heart disease (CHD) between HIV-positive patients on ART and HIV-negative patients attending same outpatient departments of general clinics in Gaborone, Botswana. Patients and Methods: Five hundred eighty-one (581) outpatients were recruited in four major clinics of Gaborone, Botswana, between June and July 2019;294 or 51% of them were HIV-negative and 287 or 49% were HIV-positive on ART. The prevalence of overweight/obesity and of HTN and DM/CHD were calculated and examined using stratified analysis. Subgroups were compared using Chi-square analysis with Yates correction or Fisher exact test and t-student test for continuous data. Results: Major findings after stratification of the study population by HIV status were: i) the prevalence of all categories of (BMI), including overweight/obesity, were comparable between HIV-negative-patients and HIV-positive. In fact, there were 24 (8.0%) cases of underweight among HIV-negative-Patients and 15(5%) cases among HIV-positive patients, p = 0.2;145 (49%) HIV-negative-patients and 128 (45%) HIV-positive, p = 0.07 cases of normal weight;72 (25%) HIV-negative-patients and 87 (30%) HIV-positive, p = 0.08, were overweight;53 (18%) HIV-negative-patients and 57 (20%) HIV-positive, p = 0.12, were obese;125 (43%) HIV-negative patients and 144 (50%) HIV-positive, p=0.06 were overweight/obese;ii) the prevalence of HTN and DM/CHD among HIV-positive-patients were significantly lower (p < 0.05) compared to HIV-negative patients: There were 32 (10.9%) cases of HTN among HIV-negative patients compared to 18 (6.3%) cases of HTN among HIV-positive patients, p = 0.001;32 (11%) cases of DM/CHD HIV-negative patients compared to 4 (1.4%) cases of DM/CHD among HIV-positive patients, p = 0.001. Conclusion: the prevalence of overweight/obesity observed between HIV-negative and HIV-positive patients may suggest that the two groups shared the same exposure factors. That HTN and DM/CHD prevalence was lower among HIV-positive compared to HIV-negative patients, is possibly due to interplay factors of ART, HIV or the host population. Further studies are, however, recommended for clarifications. 展开更多
关键词 OVERWEIGHT/OBESITY related Comorbidities HIV-positive HIV-Negative
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Principled Pragmatism: Understanding the EU Position on Economic Relations with China
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作者 Men Jing 《国际问题研究》 CSSCI 北大核心 2018年第3期216-230,共15页
关键词 Principled PRAGMATISM he EU positION on ECONOMIC relations with China
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Cooperation Benefits Both Sides While Confrontation Harms——Thoughts on Strategic Positioning of Sino-U.S. Relations
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作者 Ma Zhengang 《China International Studies》 2006年第1期35-54,共20页
关键词 rate relations Thoughts on Strategic positioning of Sino-U.S Cooperation Benefits Both Sides While Confrontation Harms
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Motor Imagery and Error Related Potential Induced Position Control of a Robotic Arm 被引量:5
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作者 Saugat Bhattacharyya Amit Konar D.N.Tibarewala 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第4期639-650,共12页
The paper introduces an electroencephalography(EEG) driven online position control scheme for a robot arm by utilizing motor imagery to activate and error related potential(ErrP) to stop the movement of the individual... The paper introduces an electroencephalography(EEG) driven online position control scheme for a robot arm by utilizing motor imagery to activate and error related potential(ErrP) to stop the movement of the individual links, following a fixed(pre-defined) order of link selection. The right(left)hand motor imagery is used to turn a link clockwise(counterclockwise) and foot imagery is used to move a link forward. The occurrence of ErrP here indicates that the link under motion crosses the visually fixed target position, which usually is a plane/line/point depending on the desired transition of the link across 3D planes/around 2D lines/along 2D lines respectively. The imagined task about individual link's movement is decoded by a classifier into three possible class labels: clockwise, counterclockwise and no movement in case of rotational movements and forward, backward and no movement in case of translational movements. One additional classifier is required to detect the occurrence of the ErrP signal, elicited due to visually inspired positional link error with reference to a geometrically selected target position. Wavelet coefficients and adaptive autoregressive parameters are extracted as features for motor imagery and ErrP signals respectively. Support vector machine classifiers are used to decode motor imagination and ErrP with high classification accuracy above 80%. The average time taken by the proposed scheme to decode and execute control intentions for the complete movement of three links of a robot is approximately33 seconds. The steady-state error and peak overshoot of the proposed controller are experimentally obtained as 1.1% and4.6% respectively. 展开更多
关键词 Brain-computer interfacing(BCI) error related potential(Errp) motor imagery decoding position control of a robot arm
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Influence of relative positions between RF coil and crucible on sapphire crystals by edge-defined film-fed growth(EFG) technique 被引量:1
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作者 吴小凤 姚正军 +4 位作者 裴广庆 罗西希 徐尚君 林玉划 杨红勤 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3731-3737,共7页
To obtain the stable temperature field required for growing sapphire crystals, the influence of relative positions between RF coil and crucible on the performances of sapphires produced by edge-defined film-fed growth... To obtain the stable temperature field required for growing sapphire crystals, the influence of relative positions between RF coil and crucible on the performances of sapphires produced by edge-defined film-fed growth(EFG) technique was investigated. For comparison, the crucible was located at the top(case A) and the middle(case B) of the RF coil, respectively. Furthermore, the lattice integrities were studied by the double-crystal X-ray diffraction, and the dislocations were observed under the optical microscope and atomic force microscope after corroding in molten KOH at 390 ℃. The crystals in case B exhibit better lattice integrity with smaller full width at half maximum of 29.13 rad·s, while the value in case A is 45.17 rad·s. The morphologies of dislocation etch pits in both cases show typical triangular symmetry with smooth surfaces. However, the dislocation density of 2.8×104 cm-2 in case B is only half of that in case A, and the distribution is more uniform, compared to the U-shaper in case A. 展开更多
关键词 sapphire single-crystal edge-defined film-fed growth two relative positions lattice integrity dislocations
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A Positive Influence Maximization Algorithm in Signed Social Networks 被引量:1
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作者 Wenlong Zhu Yang Huang +2 位作者 Shuangshuang Yang Yu Miao Chongyuan Peng 《Computers, Materials & Continua》 SCIE EI 2023年第8期1977-1994,共18页
The influence maximization(IM)problem aims to find a set of seed nodes that maximizes the spread of their influence in a social network.The positive influence maximization(PIM)problem is an extension of the IM problem... The influence maximization(IM)problem aims to find a set of seed nodes that maximizes the spread of their influence in a social network.The positive influence maximization(PIM)problem is an extension of the IM problem,which consider the polar relation of nodes in signed social networks so that the positive influence of seeds can be the most widely spread.To solve the PIM problem,this paper proposes the polar and decay related independent cascade(IC-PD)model to simulate the influence propagation of nodes and the decay of information during the influence propagation in signed social networks.To overcome the low efficiency of the greedy based algorithm,this paper defines the polar reverse reachable(PRR)set and devises a signed reverse influence sampling(SRIS)algorithm.The algorithm utilizes the ICPD model as well as the PRR set to select seeds.There are two phases in SRIS.One is the sampling phase,which utilizes the IC-PD model to generate the PRR set and a binary search algorithm to calculate the number of needed PRR sets.The other is the node selection phase,which uses a greedy coverage algorithm to select optimal seeds.Finally,Experiments on three real-world polar social network datasets demonstrate that SRIS outperforms the baseline algorithms in effectiveness.Especially on the Slashdot dataset,SRIS achieves 24.7% higher performance than the best-performing compared algorithm under the weighted cascade model when the seed set size is 25. 展开更多
关键词 positive influencemaximization polar relation information decay reverse influence sampling
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Influence of Inner/Outer Stator Pole Ratio and Relative Position on Electromagnetic Performance of Partitioned Stator Switched Flux Permanent Magnet Machines 被引量:1
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作者 J.T.Shi Z.Q.Zhu 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第3期259-268,共10页
Based on the 6-pole outer stator(armature winding-stator),the influence of inner(permanent magnet-stator)/outer stator pole ratio n(n=NIS/NOS),stator relative positions and rotor pole number combinations on electromag... Based on the 6-pole outer stator(armature winding-stator),the influence of inner(permanent magnet-stator)/outer stator pole ratio n(n=NIS/NOS),stator relative positions and rotor pole number combinations on electromagnetic performance of partitioned stator switched flux permanent magnet(PM)machines(PS-SFPMMs)is investigated in this paper.Since the armature windings and PMs are located in two separated stators and PMs are stationary,PS-SFPMMs have high fault tolerance capabilities.To maximize the torque performance,the PM of inner stator pole should be aligned with outer stator pole when n is odd while the iron rib of inner stator pole should be aligned with outer stator pole when n is even.No matter what n is selected,the rotor pole number NR can be any integers except the phase number and its multiples.The analysis results indicate that the optimal NR is closed to(NIS+NOS)/2 and it is odd when n is odd while it is even when n is even.Meanwhile,symmetrical phase back-EMF waveform will be obtained when the ratio of Min(NOS,NIS)to the greatest common divisor of Min(NOS,NIS)and NR is even.Based on the optimal rotor pole numbers for 6-pole outer stator with different n and corresponding optimal relative position together with same rated copper loss,the average torque is improved by 18.4%,25.1%and 25.7%respectively in PS-SFPMMs with n equal to 2,3 and 4 when compared with PS-SFPMM with n equal to 1.The analyses are validated by experiment results of the prototype machine. 展开更多
关键词 Inner/outer stator partitioned stator permanent magnet pole ratio relative position switched flux.
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Impact of sampling interval on variance components of epoch-wise residual error in relative GPS positioning: A case study of a 40-km-long baseline
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作者 Darko Andic 《Geodesy and Geodynamics》 CSCD 2021年第5期368-380,共13页
The study presents sampling interval impacts on variance components of the epoch-wise residual errors in relative GPS positioning. In the variance components estimation process, the 2-way nested ANOVA method was used.... The study presents sampling interval impacts on variance components of the epoch-wise residual errors in relative GPS positioning. In the variance components estimation process, the 2-way nested ANOVA method was used. For that purpose, GPS observation data during four months at two permanent GPS stations, establishing a 40-km-long baseline as a part of the Montenegrin permanent network(Monte Pos), were used. The study results showed that there is no statistically significant impact of sampling interval changes on epoch-wise variance components related to the residual tropospheric and ionospheric delays(effect a) when it comes to such a baseline. However, it is not the case with epoch-wise variance components related to the interstation-distance-independent residual ‘far-field’ multipath effect(effect b). It turned out that the absolute values of relative differences of standard deviations of the effect a on the relative GPS coordinates(e, n and u) had maximum values 11.1%, 10.2% and 8.9%,respectively. Keeping the same order of presentation for the effect b, the values of 5.9%, 9.9% and 12.5%were obtained. In addition, absolute values of relative differences of standard deviations of horizontal and vertical position had maximum values of 3.8% and 7.7%, respectively. 展开更多
关键词 relative GPS positioning Residual effects Variance components positional accuracy Sampling interval
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Relative-Position Estimation Based on Loosely Coupled UWB–IMU Fusion for Wearable IoT Devices
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作者 A.S.M.Sharifuzzaman Sagar Taein Kim +2 位作者 Soyoung Park Hee Seh Lee Hyung Seok Kim 《Computers, Materials & Continua》 SCIE EI 2023年第4期1941-1961,共21页
Relative positioning is one of the important techniques in collaborativerobotics, autonomous vehicles, and virtual/augmented reality (VR/AR)applications. Recently, ultra-wideband (UWB) has been utilized to calculatere... Relative positioning is one of the important techniques in collaborativerobotics, autonomous vehicles, and virtual/augmented reality (VR/AR)applications. Recently, ultra-wideband (UWB) has been utilized to calculaterelative position as it does not require a line of sight compared to a camerato calculate the range between two objects with centimeter-level accuracy.However, the single UWB range measurement cannot provide the relativeposition and attitude of any device in three dimensions (3D) because oflacking bearing information. In this paper, we have proposed a UWB-IMUfusion-based relative position system to provide accurate relative positionand attitude between wearable Internet of Things (IoT) devices in 3D. Weintroduce a distributed Euler angle antenna orientationwhich can be equippedwith the mobile structure to enable relative positioning. Moving average andmin-max removing preprocessing filters are introduced to reduce the standarddeviation. The standard multilateration method is modified to calculate therelative position between mobile structures. We combine UWB and IMUmeasurements in a probabilistic framework that enables users to calculatethe relative position between two nodes with less error. We have carried outdifferent experiments to illustrate the advantages of fusing IMU and UWBranges for relative positioning systems. We have achieved a mean accuracy of0.31m for 3D relative positioning in indoor line of sight conditions. 展开更多
关键词 relative position UWB IMU TRILATERATION IOT bayesian filter
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An Approach to Reasoning Topological Relations Between Areal Objects Under Randomness
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作者 DENGMin ZHANGXuesong LIUWenbao 《Geo-Spatial Information Science》 2004年第4期255-261,278,共8页
This paper describes the geometric and statistical properties of areal object under randomness. In order to describe formally such a uncertain topological relation, a new formal model (i.e. 4ID model) is proposed. On ... This paper describes the geometric and statistical properties of areal object under randomness. In order to describe formally such a uncertain topological relation, a new formal model (i.e. 4ID model) is proposed. On the basis of this, the effects of positional uncertainty on topological relations between areal objects are investigated in detail. Some possibility functions for the determination of relations are constructed based on the assumption that randomness of point location complies with a normal distribution, and the concept of uncertain sets of topological relations under randomness is introduced. 展开更多
关键词 topological relations RANDOMNESS positional error
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Design of relative position sensing system for high-speed maglev train
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作者 钱存元 Han Zhengzhi +1 位作者 Xie Weida Shao Derong 《High Technology Letters》 EI CAS 2008年第1期18-23,共6页
In the high-speed maglev system,accurate real-time information of the train position is essential forstable,safe and efficient train operation.To detect the relative position of the high-speed maglev trainfrom a refer... In the high-speed maglev system,accurate real-time information of the train position is essential forstable,safe and efficient train operation.To detect the relative position of the high-speed maglev trainfrom a reference position,a location method based on long stator slot detection was proposed.Besides,aprototype system has been successfully developed.The hardware structure of the system,as well as itsworking principle was described.Moreover,a subdivision algorithm for calculating the pole location anglesignal was elucidated.Experiments show that the proposed method is feasible.The technical indexes ofthe detection system satisfy the requirements of the vehicle operation control system.The relative positionsensing system can be put into practice. 展开更多
关键词 MAGLEV relative position linear synchronous motor SUBDIVISION
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Relative Position and Attitude Control for Drag-Free Satellite with Prescribed Performance and Actuator Saturation
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作者 TAO Jiawei ZHANG Tao 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第4期617-627,共11页
An adaptive prescribed performance control scheme is proposed for the drag free satellite in the presence of actuator saturation and external disturbances.The relative translation and rotation dynamics between the tes... An adaptive prescribed performance control scheme is proposed for the drag free satellite in the presence of actuator saturation and external disturbances.The relative translation and rotation dynamics between the test mass and outer satellite are firstly derived.To guarantee prescribed performance bounds on the transient and steady control errors of relative states,a performance constrained control law is formulated with an error transformed function.In addition,the requirements to know the system parameters and the upper bound of the external disturbance in advance have been eliminated by adaptive updating technique.A command filter is concurrently used to overcome the problem of explosion of complexity inherent in the backstepping control design.Subsequently,a novel auxiliary system is constructed to compensate the adverse effects of the actuator saturation constrains.It is proved that all signals in the closed?loop system are ultimately bounded and prescribed performance of relative position and attitude control errors are guaranteed.Finally,numerical simulation results are given to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 relative position and attitude control drag‑free satellite command filter prescribed performance actuator saturation
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Gly-LysPred: Identification of Lysine Glycation Sites in Protein Using Position Relative Features and Statistical Moments via Chou’s 5 Step Rule
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作者 Shaheena Khanum Muhammad Adeel Ashraf +5 位作者 Asim Karim Bilal Shoaib Muhammad Adnan Khan Rizwan Ali Naqvi Kamran Siddique Mohammed Alswaitti 《Computers, Materials & Continua》 SCIE EI 2021年第2期2165-2181,共17页
Glycation is a non-enzymatic post-translational modification which assigns sugar molecule and residues to a peptide.It is a clinically important attribute to numerous age-related,metabolic,and chronic diseases such as... Glycation is a non-enzymatic post-translational modification which assigns sugar molecule and residues to a peptide.It is a clinically important attribute to numerous age-related,metabolic,and chronic diseases such as diabetes,Alzheimer’s,renal failure,etc.Identification of a non-enzymatic reaction are quite challenging in research.Manual identification in labs is a very costly and timeconsuming process.In this research,we developed an accurate,valid,and a robust model named as Gly-LysPred to differentiate the glycated sites from non-glycated sites.Comprehensive techniques using position relative features are used for feature extraction.An algorithm named as a random forest with some preprocessing techniques and feature engineering techniques was developed to train a computational model.Various types of testing techniques such as self-consistency testing,jackknife testing,and cross-validation testing are used to evaluate the model.The overall model’s accuracy was accomplished through self-consistency,jackknife,and cross-validation testing 100%,99.92%,and 99.88%with MCC 1.00,0.99,and 0.997 respectively.In this regard,a user-friendly webserver is also urbanized to accumulate the whole procedure.These features vectorization methods suggest that they can play a critical role in other web servers which are developed to classify lysine glycation. 展开更多
关键词 Gly-LysPred PseAAC post-translational modification lysine glycation Chou’s 5 step rule position relative features
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An adaptive routing protocol based on relative positions in VANETs
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作者 Wang Lei Yang Yang +2 位作者 Wang Xiaobo Ibrahima Kalil Toure Mi Zhenqiang 《High Technology Letters》 EI CAS 2012年第1期13-19,共7页
After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks (VANETs) by a qualitative comparison, this paper proposes a novel self-adaptive routing protocol, named ARPP. Wit... After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks (VANETs) by a qualitative comparison, this paper proposes a novel self-adaptive routing protocol, named ARPP. With respect to the specific characteristics of VANETs, the proposed routing protocol adopts a dynamic topology establishment and time-varying control message sending mechanism. A direction-based forwarding strategy and a specific warning solution enhance the routing performance in ARPP. Simulation results show that the ARPP protocol outperforms the classic AODV in urban vehicle environment. 展开更多
关键词 vehicular ad hoc networks(VANETs) routing protocol relative positions self-adaptivemechanism
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Dependence of epoch-wise two-way nested ANOVA estimates of variances of unmodeled effects present in relative GPS positioning on satellite elevation cutoff angle and PDOP mask
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作者 Darko Andic Radovan Durovic 《Geodesy and Geodynamics》 CSCD 2022年第5期473-491,共19页
Impact of satellite elevation cutoff angle and position dilution of precision(PDOP)mask change on epoch-wise variance components of unmodeled effects that accompany relative Global Positioning System(GPS)positioning i... Impact of satellite elevation cutoff angle and position dilution of precision(PDOP)mask change on epoch-wise variance components of unmodeled effects that accompany relative Global Positioning System(GPS)positioning is presented herein.Data used for this study refer to the winter and summer periods of the years with minimal(2008)and maximal(2013)solar activity.These data were collected every 30 s in static mode,at two permanent GPS stations located in Montenegro,establishing a mediumdistance(116-km-long)baseline with a height difference of approximately 760 m between its endpoints.The study showed that changing satellite elevation cutoff angle,with a fixed PDOP mask,affects epochwise two-way nested ANOVA estimates of variances related to the‘far-field’multipath(considered as the nested factor herein)and the combined unmodeled effect of tropospheric and ionospheric refraction(considered as the nesting factor herein).However,changing of PDOP mask,with a fixed satellite elevation cutoff angle,doesn’t affect epoch-wise two-way nested ANOVA estimate of variance of the combined unmodeled effect of tropospheric and ionospheric refraction,but,generally,affects the estimate of variance of the‘far-field’multipath(possibly mixed with a part of a‘shorter-term’ionospheric refraction),which is especially pronounced for the summer period.It should also be noted that there is a significant influence of satellite elevation cutoff angle change on both epoch-wise horizontal and vertical position accuracy,only for the summer period,especially in the presence of maximal solar activity,while there is no significant impact of PDOP mask change on epoch-wise positional accuracy. 展开更多
关键词 Unmodeled effects in relative GPS positioning 2-way nested ANOVA Epoch-wise variance components Satellite elevation cutoff angle change PDOP mask change
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The Influence of Surface Building's Relative Position on the Seismic Response of Subway Structures
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作者 Li Fangjie Zhao Fengxin Zhang Yushan You Hongbing 《Earthquake Research in China》 2011年第2期250-259,共10页
By using the finite element method and viscoelastic artificial boundary, a soil-structure interaction system is established to simulate the influence of surface buildings on the seismic response of subway structures. ... By using the finite element method and viscoelastic artificial boundary, a soil-structure interaction system is established to simulate the influence of surface buildings on the seismic response of subway structures. The conditions of different relative positions between ground building and subway structure are analyzed. The result~ indicate that when considering the existence of surface buildings, the relative story displacements and internal forces of subway structures are changed greatly. Further the influence of surface buildings on subway structure changes as the distance increases. 展开更多
关键词 Subway structure Ground building relative position Seismic response
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A stealthy method to determine the relative position and velocity for satellite formation flying
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作者 田继超 崔乃刚 +1 位作者 姚劼 郭继峰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第1期137-140,共4页
To achieve the satellite formation control and the succeed formation missions, we present a new stealthy method to determine the relative states between formation satellites. In this method, the combination of a CCD c... To achieve the satellite formation control and the succeed formation missions, we present a new stealthy method to determine the relative states between formation satellites. In this method, the combination of a CCD camera and laser radar is used as the relative measure sensors. To reduce electromagnetic radiation, the laser radar works intermittently to minimize the probability of being discovered. And an unscented Kalman filter (UKF) is applied to estimate the relative states. The observability of this method is analyzed. The validity and effectiveness of the method is demonstrated in a typical application of formation relative navigation. 展开更多
关键词 formation flying unscented Kalman filter relative position and velocity
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Reference satellite selection method for GNSS high-precision relative positioning
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作者 Xiao Gao Wujiao Dai +1 位作者 Zhiyong Song Changsheng Cai 《Geodesy and Geodynamics》 2017年第2期125-129,共5页
Selecting the optimal reference satellite is an important component of high-precision relat/ve positioning because the reference satellite directly influences the strength of the normal equation. The reference satelli... Selecting the optimal reference satellite is an important component of high-precision relat/ve positioning because the reference satellite directly influences the strength of the normal equation. The reference satellite selection methods based on elevation and positional dilution of precision (PDOP) value were compared. Results show that all the above methods cannot select the optimal reference satellite. We introduce condition number of the design matrix in the reference satellite selection method to improve structure of the normal equation, because condition number can indicate the ill condition of the normal equation. The experimental results show that the new method can improve positioning accuracy and reliability in precise relative positioning. 展开更多
关键词 Global Navigation Satellite System (GNSS)relative positioning Reference satellite positional dilution of precision (PDOP)Condition number
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Method for determining the position of landslide slip-surface with a typical inclinometric curves
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作者 CHEN Hao WU Hong-gang 《Journal of Mountain Science》 SCIE CSCD 2024年第2期413-432,共20页
In the actual monitoring of deep hole displacement,the identification of slip surfaces is primarily based on abrupt changes observed in the inclinometric curve.In conventional identification methods,inclinometric curv... In the actual monitoring of deep hole displacement,the identification of slip surfaces is primarily based on abrupt changes observed in the inclinometric curve.In conventional identification methods,inclinometric curves exhibiting indications of sliding can be categorized into three types:B-type,D-type,and r-type.The position of the slip surface is typically determined by identifying the depth corresponding to the point of maximum displacement mutation.However,this method is sensitive to the interval of measurement points and the observation scale of the coordinate axes and suffers from unclear sliding surfaces and uncertain values.Based on the variation characteristics of these diagonal curves,we classified the landslide into three components:the sliding body,the sliding interval,and the immobile body.Moreover,three different generalization models were established to analyze the relationships between the curve form and the slip surface location based on different physical indicators such as displacement rate,relative displacement,and acceleration.The results show that the displacement rate curves of an r-type slope exhibit a clustering feature in the sliding interval,and by solving for the depth of discrete points within the step phase,it is possible to determine the location of the slip surface.On the other hand,D-type slopes have inflection points in the relative displacement curve located at the slip surface.The acceleration curves of B-type slopes exhibit clustering characteristics during the sliding interval,while the scattered acceleration data demonstrate wandering characteristics.Consequently,the slip surface location can be revealed by solving the depth corresponding to the maximum acceleration with cubic spline interpolation.The approach proposed in this paper was applied to the monitoring data of a landslide in Yunnan Province,China.The results indicate that our approach can accurately identify the slip surface location and enable computability of its position,thereby enhancing applicability and reliability of the deep-hole displacement monitoring data. 展开更多
关键词 Inclinometric curve Slip-surface position Displacement rate relative displacement Acceleration
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Assessing the socio-cultural impact of urban revitalisation using Relative Positive Impact Index(RPII)
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作者 Shahim Abdurahiman A.K.Kasthurba Affa Nuzhat 《Built Heritage》 CSCD 2024年第1期67-83,共17页
Urban heritage is a vital resource that connects communities to their local identity.Unplanned developments and rapid urbanisation often harm the authenticity of historic areas,disrupting the cultural fabric and alter... Urban heritage is a vital resource that connects communities to their local identity.Unplanned developments and rapid urbanisation often harm the authenticity of historic areas,disrupting the cultural fabric and altering their character.This study introduces the Relative Positive Impact Index(RPll),a novel technique for assessing the socio-cultural impacts of urban revitalisation.The significance of RPII lies in its ability to quantitatively evaluate the impacts on the cultural fabric and integrity of historic urban areas,which is crucial for sustainable urban development.The study's objective is to apply RPII in evaluating qualitative socio-cultural characteristics in historic urban areas,with a focus on four main criteria and 16 sub-criteria,in the case of the Kuttichira precinct.The methodology integrates the analysis of published literature,a quantitative survey mapping the stakeholders'perception,and qualitative insights.This approach facilitates an in-depth understanding of how urban revitalisation affects local socio-cultural dynamics,preserving the authenticity and character of historic areas.The study reveals that the revitalisation project in Kuttichira positively impacts the socio-cultural fabric of the area,maintaining cultural integrity and addressing social challenges.These findings offer valuable insights for sustainable urban development and policymaking in historic areas.The study recommends the application of RPll in other urban precincts for comparative analysis and further development of urban development practices,contributing to informed urban policy and planning decisions. 展开更多
关键词 urban revitalisation socio-cultural impact relative positive impact index urban heritage sustainability
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