In recent years, there have been a significant influenza activity and emerging strains in China, resulting an increasing number of virus infections leading to public health concerns. The aims this study were identify the epidemiological aetiological characteristics establish seasonal autoregressive integrated moving average (SARIMA) models for forecasting percentage visits influenza-like illness (ILI%) urban rural areas Shenyang. Influenza surveillance data obtained ILI cases positivity from...

Abstract Precise point positioning (PPP) is famous for its capability of high-precision with just one station as long the receiver can receive global navigation satellite system (GNSS) signals. With rapid development BDS and Galileo, number available satellites has increased significantly. In addition, GPS III, GLONASS-K, BDS, Galileo transmit triple-frequency The potentials multi-constellation GNSS PPP requires further analysis on a scale. Therefore, we selected 96 multi-GNSS experiment...

Abstract PPP-RTK is Precise Point Positioning (PPP) using corrections from a ground reference network, which enables single-receiver users with integer ambiguity resolution thereby improving its performance. However, most of the studies are investigated and evaluated in static situation or post-processing mode because complexity implementation real-time practical applications. Moreover, although achieves faster convergence than PPP, it typically needs 30 s even longer to derive high-accuracy...

Landslides and ground subsidence pose significant threats to the successful construction operation of transmission line projects in Loess Plateau region. This study aims explore an accurate early identification method for geological hazards, providing support smooth project along route from Baishui County, Weinan City, Shaanxi Province Lantian Xi’an Province. Small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technology was used acquire surface deformation data area...

In this paper, a 5km area along the 750kV Third passage project in Shaanxi Province is taken as research area. Based on analysis of application and limitation traditional two-dimensional regression model land subsidence simulation, advantages multi-scale geographical weighted automatically calculating bandwidth exploring spatial heterogeneity impact factors are explored. geological environment region latest disaster data, seven influencing including slope, topographic relief, average annual...

For GPS medium-long baseline real-time kinematic (RTK) positioning, the troposphere parameter is introduced along with coordinates, and model ill-conditioned due to its strong correlation height parameter. BeiDou Navigation Satellite System (BDS), additional difficulties occur special satellite constellation. In fact, relative zenith delay (RZTD) derived from high-precision empirical models can be introduced. Thus, strength improved, which also called RZTD-constrained RTK model. this...

Advanced driver-assistance system (ADAS) and high levels of autonomy for vehicular applications require reliable precision pose information their functioning. Pose estimation comprises solving the localization orientation problems a rigid body in three-dimensional space. In outdoor scenarios, fusion Global Navigation Satellite Systems (GNSS) inertial data high-end receivers constitutes baseline ground truth solutions, such as Real-Time Kinematic (RTK) or Precise Point Positioning (PPP)....

Abstract Background Since 2011, there has been an increase in the incidence of scarlet fever across China. The main objective this study was to depict spatiotemporal epidemiological characteristics Shenyang, China, 2018 so as provide scientific basis for effective strategies control and prevention. Methods Excel 2010 used demonstrate temporal distribution at month level ArcGIS10.3 spatial district/county level. Moran’s autocorrelation coefficient examine Getis-Ord statistic determine...

Surface temperature and pressure are indispensable variables in Global Navigation Satellite System (GNSS) meteorology. The lack of meteorological observations located at or near the GNSS sites is a big challenge for calculation accurate zenith hydrostatic delay (ZHD). Therefore, various empirical models with different model forms were established to provide values. In this study, influence modelling factors, including forms, temporal resolution data sources, spatial evaluated best...

With the emergence of BeiDou and Galileo as well modernization GPS GLONASS, more available satellites signals enhance capability Global Navigation Satellite Systems (GNSS) to monitor ionosphere. However, currently International GNSS Service (IGS) Ionosphere Associate Analysis Centers (IAACs) just use GLONASS dual-frequency observations in ionosphere estimation. To better determine global ionosphere, we used multi-frequency, multi-constellation a priori Reference (IRI) model The newly...

Abstract Traditionally, the ionosphere determination just uses American Global Positioning System and Russian GLObal NAvigation Satellite dual‐frequency data has a low precision particularly on oceans. With rapid development of Chinese BeiDou European Galileo systems, they are playing an increasingly important role for modeling global ionosphere. Meanwhile, satellite altimetry provides valuable precise delay over Through introducing priori values from advanced empirical model, combining...

Site-dependent effects are now the key factors that restrict high accuracy applications of Global Navigation Satellite System (GNSS) technology, such as deformation monitoring. To reduce non-line-of-sight (NLOS) signal and multipath, methods models applied to both function model stochastic least-squares (LS) have been proposed. However, existing may not be convenient use appropriate all GNSS satellites. In this study, SNR features GPS GLONASS analyzed first, a refined based is proposed, in...

Inland waterway transport (IWT) is an efficient way of mass good transportation with low energy consumption and reasonable ecological impact. As for other systems, there a need reliable advanced driver-assistance functions increased autonomy. In this regard, High Definition (HD) Maps play role by enhancing vessels' localisation perception capabilities. Obtaining HD important step towards the ongoing digitalisation water-based forms basis assistant systems to captains inland vessels or even...

It is difficult to enable traditional precise point positioning (PPP) with ambiguity resolution (AR) due fractional cycle biases (FCBs), which limit the accuracy and reliability of results. The BeiDou Navigation Satellite System (BDS) has been providing continuous positioning, navigation, timing (PNT) services in global region since end 2018. BDS constellation includes geostationary earth orbit (GEO), inclined (IGSO), medium (MEO) satellites. However, its hybrid structure satellite-side...

Real-time Kinematic (RTK) positioning provides centimeter-level accuracy within several seconds, but it has to rely on a nearby base station. Although Precise Point Positioning (PPP) supplies precise positions with one receiver, its convergence time takes tens of minutes, which makes PPP not well suited for real-time kinematic applications where rapid is required. PPP-RTK integrates the benefits and RTK, actually augmented by ground GNSS network. The satellite orbit, clock offsets, signal...

The high-precision satellite velocities and accelerations calculated by the Global Navigation Satellite System (GNSS) are essential for tasks such as airborne gravity data processing. Users generally interpolate positions in precise ephemeris to calculate velocity acceleration. However, due edge effect, accuracy of interpolation is relatively low near day boundaries. In this study, a method calculating GNSS acceleration based on orbit fitting integration was proposed, transformation...