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This chapter presents the design of a system of fuzzy controllers for a differential mobile robot that was developed to navigate in outdoors environments over a predetermined route from point A to point B without human intervention. The mobile robot has the main features of geo-navigation to obtain its current position during the navigation, obstacles detection and the avoidance of these obstacles in an autonomous form. In this work to achieve the autonomous navigation in real-time, it was necessary to design a system based on fuzzy controllers. The system performs the detection and the analysis of the surrounding environment of the mobile robot to take actions that allow achieving the target point in a safe way. The position and orientation of the mobile robot is achieved with the use of geographical coordinates, through a GPS and the use of a magnetic compass which determines the steering angle. The detection of the environment is through ultrasonic sensors mounted on the mobile robot. All the inputs are taken by the system to compute through fuzzy rules the motion control of the mobile robot, to estimate the position and orientation accurately and to control the speed of the two DC motors to drive the wheels. In this work, the experiments were performed in dynamic outdoors environments, where the mobile robot performed successfully the navigation and the obstacles avoidance. In all the experiments, the mobile robot achieved its mission to reach the target position without human intervention; the results show the validity of the developed system. The experimental framework, experiments and results are explained in terms of performance and accuracy. [ABSTRACT FROM AUTHOR]

This chapter describes the preliminary study of real-time data streaming in support of the proposed low-cost landslide monitoring system using the Reverse Real-Time Kinematic (RRTK) technique. The RRTK algorithm was implemented by streaming raw Global Positioning System (GPS) data of both the reference and roving station(s) to the control centre for processing, and transmission of the position solution to the roving station. The main purpose of the data streaming was to investigate the quality of the measurements, for utilization in landslide modelling and analysis in near real-time. A novel methodology using a high pass filtering technique was implemented, to detect outliers in the observations. Also, the autocorrelation of GPS time series was investigated. [ABSTRACT FROM AUTHOR]

In geographic search tasks, where the location of the user is an important part of the task context, knowing whether or not a user has visited a location associated with a returned result could be a useful indicator of system performance. In this paper we derive and evaluate a model to estimate, based on user interaction logs, GPS information and event meta-data, the events that were visited by users of a mobile search system for an annual cultural evening where multiple events were organised across the city of Munich. Using a training / testing set derived from 111 users, our model is able to achieve high levels of accuracy, which will, in future work, allow us to explore how different ways of using the system lead to different outcomes for users. [ABSTRACT FROM AUTHOR]

This paper presents a geographically distributed mobile teamwork management system that combines the simplicity of Web services architecture and protocols, with the GPS-based location information retrieval, and a geographical mapping application. The aim of our work is to offer a Web-based client-server system heading towards a better management of mobile teamwork departments (such as operating and maintenance departments of telecommunications companies) in the idea of making more efficient use of overall resources. [ABSTRACT FROM AUTHOR]

One opportunity to manage the increase of freight transportation and to optimize utilization of motorway capacities is the concept of truck platoons. With the aid of Advanced Driver Assistance Systems, trucks are electronically coupled keeping very short gaps (approx. 10 meters) to form truck platoons on motorways. This contributes to optimization of traffic flow and reduction of fuel consumption advantaged by slipstream driving. In this paper, a brief introduction into these truck platoons is given as well as a short overview about the elements of the automation-, information- and automotive-technology of the experimental trucks. The paper focuses on the determination of the order of the electronically coupled trucks, which is essential to organize and operate these platoons. The order is necessary for the communication between trucks in order to receive the correct information via vehiclevehicle- communication. An algorithm for the determination of the order of vehicles on motorways based on GPS-data is derived, which finally has been applied on test drives. [ABSTRACT FROM AUTHOR]

The altimeter range should be corrected for tropospheric path delays due to atmospheric pressure at sea level and atmospheric humidity. Over open ocean, these corrections are performed with enough accuracy using the microwave radiometer for the wet path delay and meteorological model analyses for the dry path delay. In coastal areas, specific studies are needed to assess the quality of the standard products and to propose specific processing if necessary. For the wet tropospheric correction, new promising approaches are presented based on optimal combination of radiometer, meteorological model, GNSS and land information. For the dry tropospheric correction, an assessment of the accuracy of the model-based estimation is provided. [ABSTRACT FROM AUTHOR]

The determination of global and regional mean sea level variations with accuracies better than 1 mm/year is an important yet challenging problem, the resolution of which is central to the current debate on climate change and its impact on the environment. To address this, highly accurate time series from both satellite altimetry and tide gauges are needed. In both cases, the desired accuracy represents a significant challenge for the geodetic community. From the perspective of space borne altimetry, systematic errors from the orbit, reference frame and altimeter systems are all important limiting factors and must be minimized in order to derive data products of greatest geophysical value. Indeed, the objective for the overall accuracy of future altimeter systems is 1-cm (RMS) along with a stability of 1 mm/year. From the terrestrial perspective, estimating the vertical velocity of tide gauge sites to sufficient accuracy is also one of the most important and challenging problems in modern geodesy. Essential to reaching these goals in the measurement of mean sea level variation are ultra-precise validation and calibration techniques, including in situ absolute calibration experiments. Most of the present calibration experiments are on or near the coast, reinforcing the need for developing such techniques to unify the altimetric error budget for both open-ocean and local (coastal) conditions. [ABSTRACT FROM AUTHOR]

Advanced GIS applications and GPS loggers allow travelers to record their own tracks and later examine, modify and share them. Searching for the areas of interest, AOIs, however, is often not an easy task, especially with long routes. This paper proposes a system for inferring and focusing AOIs, from a GPS trace. The proposed system consists of three main functions: fragmentation, defragmentation, and focusing. The fragmentation detects the changes of the travelling pace and decomposes the GPS trace into a large number of small fragments according the traveling pace while the defragmentation composes adjacent fragments into one fragment which is inside the AOI. The focusing provides a Focus+Context+Glue map where the Focus is an area of a large-scale map including the AOI that enables users to understand details of the AOI. We have developed a prototype of the proposed method that includes the above features and evaluated the feasibility and advantages of the proposed system. [ABSTRACT FROM AUTHOR]

The paper describes the results of an engagement in the international cooperation within the EDCN network and it draws conclusions based on experience in monitoring of the EGNOS system. The experience gained by the authors in the EDCN project course is expected to have a serious impact on the research and development dedicated for enhancement of the reliability of the EDCN network. Therefore, in the paper not only are the current results of cooperation presented, but also the challenging issues, which are to be resolved in the future based on the conclusions drawn on the experience gained. [ABSTRACT FROM AUTHOR]

Laser-controlled land leveling system can obviously improve the planeness of the field and enhance the efficiency of irrigation. The 3D topographic information was needed for project design and evaluation of laser land leveling. In order to obtain the topographic information efficiently, an onboard field 3D topography surveying system was developed. The surveying system consisted of a measuring laser receiver, a GPS receiver, a controller and a hydraulic system. Besides topographic measurement, the system could also achieve laser land leveling. The measuring laser receiver was used to obtain the elevation and the GPS receiver was employed to obtain the longitude and latitude data. The data was fused in the controller to get the 3D topographic information. Field experiments were carried out in different speed and compared with the data from the fixed-point surveying method. The result showed the surveying system had a good consistency with the fixed-point surveying method in slower speed. [ABSTRACT FROM AUTHOR]

The paper introduces the problems in china΄s agricultural machinery information. We provide an architecture for the agricultural machinery intelligent scheduling in cross-regional work. We put forward constructing the private cloud of agricultural machinery with the aid of cloud computing technology, and forward agricultural machinery will link together through Internet of Things technology. We provide an information platform and simplified it to three components including information service system, communication line and monitoring front-end equipment machine carrying. We also describes two modes to realize the intelligent scheduling function of agricultural machinery cross-regional working. [ABSTRACT FROM AUTHOR]

In Intelligent Vehicular Networks, featured as car-to-car and car-to-infrastructure wireless communication, most applications need important location information or credential information. We address a location-based encryption method that not only ensures messages confidentiality but also authenticates identity and location of communication peers. The authentication of location means that a message can only decrypted by the receiver which is ˵physically″ present inside a decryption region specified by locations, and is moving at a specific speed, acceleration and at a specific time period. A secret key is generated by converting location, time and mobility information (such as speed and acceleration) into a unique number. The determination of the decryption region is addressed in two steps: predicting and updating. The proposed method evaluated by simulations is efficient and secure. [ABSTRACT FROM AUTHOR]

This paper analyses the statements of video imaging, CT, infrared thermography and radiography applied in the road nondestructive testing, and design a path planning mobile robot with GPS positioning which can remarkably increase the efficient of road nondestructive testing. Besides, appropriate algorithm for nondestructive testing on the road autonomous mobile robot path planning is given. This method is simplicity, versatility, and efficiency. The mobile robot are selected for example and the simulation results represent the effectiveness of this method. [ABSTRACT FROM AUTHOR]

Routing has been the main challenge for ad hoc networks due to dynamic topology as well as resource constraints. Completely GPS free as well as GPS scarce positioning systems for wireless, mobile, ad-hoc networks has been proposed recently by many authors. High computational overhead and high mobility of the nodes typically require completely GPS enabled MANETs for higher performance. In this paper, Improved Location aided Cluster based Routing Protocol (ILCRP) for GPS enabled MANETs has been evaluated for performance metrics such as end to end delay, control overhead, and packet delivery ratio. Use of cluster based routing as well as exact location information of the nodes in ILCRP reduces the control overhead resulting in higher packet delivery ratio. GPS utility in nodes reduces the end to end delay even during its high mobility. Simulations are performed using NS2 varying the mobility (speed) of nodes as well as number of the nodes. Results illustrate that the ILCRP performs better compared to other protocols. [ABSTRACT FROM AUTHOR]

In this article we discuss the strategic use of visitor tracking data in the good management of visitor attractions and tourist destinations, also highlighting the challenges that could be presented by tracking visitors in different attraction types and sites. Based on the practice and results from a tracking experiment in the PortAventura theme park, an enclosed and controlled environment, we then illustrate the actual and potential uses that attraction managers can do of this information, proposing a number of logistic and technical solutions to enhance the use of tracking data in this specific type of attractions. Finally, the paper present a future research agenda into visitor spatial behaviour using tracking technologies in semi-open and open environments other than theme parks and leisure attractions. [ABSTRACT FROM AUTHOR]

Recent technological developments have produced a range of sophisticated and readily available digital tracking technologies, of which the best known is the Global Positioning System [GPS]. Yet, despite this remarkable surge in technology, researchers in the field of tourist studies have failed to take full advantage of what these relatively new systems have to offer. Tracking technologies are able to provide high-resolution spatial and temporal data that could potentially, aid, augment, and advance research in various areas in the field of tourist studies. This article present the possibility to use aggregative data obtained from GPS receivers in order to better understand the impact of visitors on destinations. The data presented in this paper were collected in four different locations: PortAventura amusement park and the Mini Israel theme park (two enclosed outdoor environments) the Old City of Akko in Israel (a small historic city) and Hong Kong a truly World City. [ABSTRACT FROM AUTHOR]

This chapter presents results from a 1-year field experiment in West Africa deploying a suite of ground-based instrumentation. Weather and climate over tropical West Africa are determined by the annual cycle of the West African monsoon. The relationships between the monsoon season and the displacements of the inter-tropical convergence zone and the inter-tropical discontinuity are briefly remarked, as well as the importance of atmospheric humidity in determining the strength of the monsoon. The scarce and discontinuous observations in the West Africa region cause lack of measurements with high temporal resolution and diurnal-to-annual coverage; conversely, long-term and continuous monitoring is essential for deepening the understanding of the mechanisms that are responsible for inter-annual variability of the West African monsoon. Within the African Monsoon Multidisciplinary Analysis project a wealth of observations from ground-based instrumentation, such as microwave radiometer, ceilometer, and microrain radar, were possible for a period of one year or more. The complete annual cycle of cloud cover, integrated water and liquid contents, and temperature profiles are reported. Furthermore, a distinct diurnal cycle, connected with the move of the inter-tropical discontinuity before the onset of the wet season, was observed and used to evaluate a mesoscale model. [ABSTRACT FROM AUTHOR]

The UK Space Geodesy Facility has operated a highly precise Satellite Laser Ranging station at Herstmonceux in southern England for over 25 years and the laser ranger is one of the ILRS core stations. It also operates two GNSS receivers contributing to IGS for over 14 years, and an Absolute Gravimeter (AG) which provides 24-h data weekly since November 2006. The facility has environmental monitoring in the form of a borehole, in close proximity to both the SLR and the gravimeter room, which provides automatic ground-water level measurements, and precise temperature, pressure and humidity devices. In this work we will investigate time series of site height variations determined by the independent techniques of SLR, AG and GPS since November 2006. The geodetic results suggest annual periodic vertical variations of amplitude about 15 mm and the absolute gravity values show systematic variations of order four microgals. We are particularly interested in the hydrological effects on the gravimeter data and will aim to use the space geodetic results to separate them from local vertical signals. [ABSTRACT FROM AUTHOR]

KTIMATOLOGIO S.A. developed the HEllenic POsitioning System (HEPOS) for facilitating the establishment of the National Cadastre in Greece. HEPOS is a modern RTK-network consisting of 98 permanent GPS reference stations distributed throughout Greece. Like in any other RTK-network, the coordinates of the reference stations must be estimated with high accuracy, on the order of 1 cm. This requirement is a great challenge for HEPOS, due to the strong geodynamic effects taking place in Greece. Besides the slow displacements caused by the individual velocities of the different tectonic plates, abrupt displacements may occur as a result of strong earthquakes. During the first months of the operation of HEPOS, several strong earthquakes (ML >6.0) with different characteristics took place in certain areas of Greece. By post-processing and analyzing GPS observations of the reference stations of HEPOS, it was proved that some earthquakes have detectable effects on the positions of the reference stations. The paper describes the methodology that has been used for revealing these effects as well as the results that have been obtained. [ABSTRACT FROM AUTHOR]

We have conducted various experiments of sea surface height (SSH) measurements in Greece΄s Aegean Sea using on-board kinematic GPS recordings and the KMSS04 satellite altimetry-derived mean sea surface for comparison. This region is of particular interest because of strong crustal movements due to intense tectonic activity that create significant local geoid variations. In this paper, we report on the results of separate SSH surveys that were conducted in three test areas in the Aegean Sea. Ship borne GPS data were collected together with GPS data simultaneously collected at nearby mainland reference stations. These high rate data were processed in kinematic mode using scientific GPS software and related to SSH observations, thus allowing us to obtain maps of the instantaneous sea surface, which was estimated with a precision at the level of a few centimeters. Tidal recordings from nearby tidal stations provided us with the required tidal corrections for the reduction of the GPS-derived SSHs to mean sea level (MSL). Following a filtering process, a cross over adjustment and gridding of the pointwise SSH observations in each test area, local maps of the mean sea surface (MSS) were obtained, which can be compared with the available KMSS04 global solution for the MSS. To examine further the MSS-related results that we observed in these experiments, we compared both the GPS-derived and the KMSS04-related MSS with JASON-1 radar altimetry and ICEsat laser altimetry data over the same areas. We show that the SSHs derived from the GPS ship surveys, when carefully analyzed and applying suitable filtering techniques and necessary corrections for the Dynamic Ocean Topography (DOT) can provide enhanced shorter wavelength components of the local geoid. This is illustrated with additional comparisons with the EGM96 and EGM08 global geoid models, in order to reveal any significant differences, mainly in the short wavelength domain, when compared to the aforementioned local geoid models computed from purely GPS-derived SSH data. [ABSTRACT FROM AUTHOR]

We investigate loading consequences on the time-variable GPS station positions of one hundred stations around the world during the 2001–2006 time period. We model the three dimensional site displacements using a Love number formalism to describe the elastic deformation of a spherical Earth model submitted to atmospheric, oceanic and hydrological loadings. We produce site position time series using the GPS analysis software GAMIT/GLOBK with or without inserting a combination of loading models and study their impact on 3D site positions. First of all, we compare the variability of modeled and observed site positions without integrating loading. We secondly study the variability reduction in the GPS site positions provided by the loading when integrating it in the GAMIT Software as an a priori contribution to the station motion model. We conclude that the seasonal variability of site vertical displacement is quite well explained by our model at several locations, mainly located at mid-latitudes in the northern hemisphere, while it is much less understood near coastal areas. [ABSTRACT FROM AUTHOR]

In this paper we present a method for detecting three-dimensional systematic errors of Digital Surface Models (DSMs) derived from satellite data. The detection process is realized via a three-dimensional comparison with reference altimetric models of better accuracy, by a matching process based on a 3D geospatial transformation without scale factor correction. The matching process of the two altimetric models is based on the estimation of the six parameters of a geospatial transformation between two 3D surfaces, minimizing the Euclidean distances between the surfaces by least squares method; this procedure does not require the a priori availability of homologous points. The method is applied on comparison of GPS surveys over Lombardy Region of Northern Italy, with SRTM (3 arc sec) and ASTER (1 arc sec) DSMs in the same region; tests of statistical significance are performed confirming, in the latter case, the existing 3D systematic error. [ABSTRACT FROM AUTHOR]

This paper shows a lightweight technique for extending the positioning capabilities of a global navigation satellite system to areas characterized by reduced satellite visibility. This technique includes the presence of a WiFi coverage, used to implement the virtual satellite concept. In particular we assume that a customer terminal can receive both Global Positioning System (GPS) signals and WiFi beacons broadcasted by an access point (AP). We show that if such beacons include the geo-referenced position of the relevant AP, the suitable usage of this information allows determining the GPS receiver position even if only three satellites are visible. Experimental results show that the achievable performance are similar to that obtainable by a plain GPS receiver using four visible satellites. [ABSTRACT FROM AUTHOR]

Galileo is the program that has been launched by the European Union for the purpose of building a Global Navigation Satellite System (GNSS) for serving civilians and to exist under civil control. Our project combines many previous researched scenarios for Galileo system to a final one, which has been simulated and adjusted to meet the most demanding standards (of proposed GNSS services). The final simulated scenario is consisted of 30 (27+3 spare) satellites allocated in 3 orbital planes. [ABSTRACT FROM AUTHOR]

Global Positioning System (GPS) is a popular technology applied in many areas and embedded in many devices, facilitating end-users to navigate effectively to user΄s intended destination via the best calculated route. The ability of GPS to track precisely according to coordinates of specific locations can be utilized to assist a Muslim traveler visiting or passing an unfamiliar place to find the nearest mosque in order to perform his prayer. However, not many techniques have been proposed for Mosque tracking. This paper presents the development of GPS technology in tracking the nearest mosque using mobile application software embedded with the prayer time΄s synchronization system on a mobile application. The prototype GPS system developed has been successfully incorporated with a map and several mosque locations. [ABSTRACT FROM AUTHOR]

As an alternative to expensive road surveys, we are working toward a method to infer the road network from GPS data logged from regular vehicles. One of the most important components of this problem is to find road intersections. We introduce an intersection detector that uses a localized shape descriptor to represent the distribution of GPS traces around a point. A classifier is trained on the shape descriptor to discriminate intersections from non-intersections, and we demonstrate its effectiveness with an ROC curve. In a second step, we use the GPS data to prune the detected intersections and connect them with geometrically accurate road segments. In the final step, we use the iterative closest point algorithm to more accurately localize the position of each intersection. We train and test our method on GPS data gathered from regular vehicles in the Seattle, WA, USA area. The tests show we can correctly find road intersections. [ABSTRACT FROM AUTHOR]

Dementia is a chronic brain disease affecting cognitive functioning. People with dementia have a higher risk of getting lost. In recent years GPS based technology has been utilised to locate lost persons with dementia. We interviewed six families using such technology focusing on perceived usability, user-friendliness and usefulness. The informants also completed the QUEST 2.0 questionnaire which measures satisfaction with assistive technology. By and large the informants found the equipment easy to use, and it was viewed by all as being very useful. There were a number of usability issues which adversely affected usage, e.g. system stability, secure fastening, size, user interface issues and varying GPS-reception. The QUEST 2.0 results corresponded with the findings in the interviews. Further usability studies, as well as R&D to address issues such as security and privacy protection and use in the public health sector are needed. [ABSTRACT FROM AUTHOR]

Real-time information about traffic flow, accidents, or road availability is very important for drivers, and it is useful to implement a messaging system for supporting inter-vehicular communication. Aided by positioning instruments and ad hoc network, important messages can be sent from vehicle to vehicle to regulate traffic flow, enhance driving safety and distribute alert messages. We identified various types of broadcasting and analyzed the circumstances for broadcasting. The usefulness of broadcasting was considered in which a message about an accident is important for vehicles approaching the accident, and the information that an ambulance is coming is also important for vehicles before the ambulance. LAN and 3G provide a communication platform for messaging. Broadcasting, P2P communication and SMS are a choice for the messaging system. A prototype of the system was implemented and its application was discussed as well. [ABSTRACT FROM AUTHOR]

One of the goals of Intelligent Transport Systems (ITS) is to reduce traffic accidents and enhance safety. However, plenty of technologies for safe driving can not prevent traffic accidents, if a driver does not understand what safe driving is exactly. Thus, driver education is quite important even if ITSs spread. However, most educational methods for safe driving are subjective and lacking in concreteness. We have proposed safe driving theory based on a mechanism of collision and human cognitive characteristics. In this paper, we report an ASSIST, which stands for an Assistant System for Safe Driving by Informative Supervision and Training, and was created to prevent accidents based on our safe driving theory. The ASSIST uses sensors in a vehicle, computers, mobile phones and the Internet. We report development of web based management software for safe driving on the ASSIST. [ABSTRACT FROM AUTHOR]

In Japan, population of aged people is becoming greater. According to it, number of the wheelchair user would become larger. The government has being improved to lessen the barriers for these people. But depending on the physical power of wheel chair users, it was pointed out that there could be the places where they could not move by their physical power. This is a reason that many wheelchair users do not move by their alone. Therefore we tried to develop the navigation system to eliminate the problem. At the beginning we have developed the system to measure the required force to move the wheelchair, the width of the space of aisle where they could turn back the direction, and the position information. By the data base, we planned to develop the navigation system for wheelchair users who could move alone to working places or other places where they want to go. In this paper, we report the system developed to collect data for navigation of wheelchair users. [ABSTRACT FROM AUTHOR]