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Many Vehicular Ad-hoc Networks (VANETs) applications require that each vehicle knows precisely its current position in real time. The Global Positioning System (GPS) is technology most widely used to determine the positioning of vehicles in VANETs. However, the GPS has several drawbacks, one of them is the lack of accuracy of the measurement of impact is the most unacceptable disadvantage. In this...
Trajectory models have numerous applications in the area of wiewlwss communications. The aim of this paper is to develop an empirical trajectory model for drifted motions. Recently, a highly flexible trajectory model based on the primitives of Brownian fields (TramBrown) was proposed by A. Borhani and M. Pätzold. This paper provides an empirical proof for TramBrown using global positioning system...
Lane-based road network information, such as the number and locations of traffic lanes on a road, has played an important role in intelligent transportation systems. In this paper, we propose a Collecting Lane-based Road Information via Crowdsourcing (CLRIC) method, which can automatically extract detailed lane structure of roads by using crowdsourcing data collected by vehicles. First, CLRIC filters...
This paper proposes an efficient hybrid positioning method for land vehicles in urban area. As widely known, any single satellite positioning system suffers from the lack of satellite visibility in urban area. To improve positioning availability in urban area, the proposed method integrates a GPS/BeiDou receiver, an OBD-II (On-Board Diagnostics-II) device, and a MEMS IMU (Micro Electro Mechanical...
Energy efficiency has become one of the major concerns in railway operation today. Generation of energy-efficient train trajectories can be modeled as solving a complex optimization problem with nonlinear and time-varying variables under multiple constraints of equality and inequality, as train operation is a dynamically vacillating process due to complex railway operational conditions. In recent...
With the rapid development of GPS devices, satellite and wireless communications technologies, many trajectory data is generated. Consequently, processing and analyzing trajectory data have become a hot topic. In this paper, an improved noise filtering, trajectory compression and trajectory segmentation method based on Kalman filter and Douglas-Peucker algorithm and corner is proposed. Firstly, the...
This paper proposes a position accuracy improvement algorithm for a low-cost global positioning system (GPS) receiver of a car navigation system considering a distance boundary. The proposed method enhances the position accuracy by matching the trajectory of a vehicle acquired by a GPS receiver with prebuilt map information. After acquiring the trajectory of a vehicle, the iterative closest point...
In the calculation process of spatial-temporal co-occurrence patterns, traditional methods often set the whole time frame as the actual existence time by default for all moving targets. However, in practice, existence time frame of different types is not necessarily the whole time frame. Based on this fact, the paper describes the calculation method of spatial-temporal interest degree-spatial frequency...
This paper presents a new design of vehicle remote monitoring system. ARM9 core processor, GPRS module, GPS module, sensor module and display module are used to build a car terminal. And develops a piece of software that runs on monitoring center server with .NET development. Based on these, a client software based on android platform is developed to help user to manage their car. The whole system...
We consider a target tracking problem where, in addition to the usual sensor measurements, accurate observations with uncertain timestamps are available. Such observations could, e.g., come from traces left by a target or from witnesses of an event, and have the potential in some scenarios to improve the accuracy of an estimate significantly. The Bayesian solution to the smoothing problem for one...
The growth of the world's population and the dramatic increase in average life expectancy raise awareness of the global burden of elderly diseases. Mild cognitive impairments affect elderly people, which suffer a deterioration of their capabilities, with special regard to memory. Such problems often lead to disorientation or wandering: erratic movements and changes in mobility and behavioural patterns...
Urban travel characteristics is an essential apart of urban crowd flow analysis. Floating car data, known as “FCD”, have been recorded taxis' routine trajectories in cities, which can draw the characteristics of urban crowd flow. As a large volume of datasets, floating car data need an efficient way to process and analyze. A Hadoop-GIS methodology is used in this paper, consists of two major tools...
In this study, we proposed a user relationship strength hierarchy vote (URSHV) model to measure the relationship strength, which can reflect the degree of intimacy between two different persons. This model is a hierarchical model measuring the relationship by voting on users' daily moving trajectory similarity, physical position similarity,, the corresponding semantic location similarity, capable...
Mobility motif is a typical topology structure shared by movement trajectories, which could exhibit multi-scale spatio-temporal patterns in human behavior. There are two types of motifs, frequent, infrequent. The infrequent one hasn't got enough attention in research. In this paper, we study the relationship between infrequent motifs, mass activities. We have discovered that crowds are more likely...
Coordinated animal behavior is abundant in nature, such as the uniform moving phenomenon among bird flocks, the collective evasion maneuvers of fish schools. To explore the appealing inter-individual interaction mechanism governing the abundant biological grouping behaviors, more and more efforts have been devoted to collective motion investigation in recent years. Previous research claims the existence...
Trajectory simplification is a problem encountered in areas like Robot programming by demonstration, CAD/CAM, computer vision, and in GPS-based applications like traffic analysis. This problem entails reduction of the points in a given trajectory while keeping the relevant points which preserve important information. The benefits include storage reduction, computational expense, while making data...
At present, it is a hot-spot in the research of data mining to mine mobility patterns on the basis of GPS trajectories. In order to solve the problems that data sampling frequency uncertainty, the value of experience as period parameter by human input, and spatiotemporal noises and outliers, we propose a framework called PMPM (Periodic Mobility Pattern Mining) to adaptively detect periodic parameters...
In this paper relative dispersion of satellite-tracked GPS-equipped drifters of the GLAD campaign in the Gulf of Mexico was investigated. Relative dispersion and relative velocity variance were computed pointing out different growth regimes. An exponential growth of the dispersion was detected and confirmed on the initial phase of deployment. The influence of the GPS-position error, in relation with...
This paper presents a design and implementation of an unmanned aerial vehicle (UAV) for outdoor firefighting application. The proposed UAV firefighting system consists of a self-designed quadcopter as platform, a transmission system to collect and release water, a real time kinematic (RTK) based navigation system and a mission control system to monitor and coordinate the UAV. In our proposed autonomous...
Cargo transportation between moving platforms is one of the most meaningful potential applications of UAVs. However, to fully autonomously transport the cargos, the UAV is required to have high position precision and high intelligence to tackle all the emergencies, on which the technology is not mature yet. In this article, we present a quadrotor system targeting at fully autonomous cargo transportation...
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