Global Positioning System

This paper presents the results of ground vibration measurements carried out in Hisarcik Boron open pit mine located on the west side of central Anatolia near Kütahya province in Turkey. Within the scope of this study to predict peak particle velocity (PPV) level for this site, ground vibration components were measured for 304 shots during bench blasting. In blasting operations, ANFO (blasting agent), gelatin dynamite (priming), and delay electric detonators (firing) were used as explosives. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured for all blast events using two different types of vibration monitors (one White Mini-Seis and one Instantel Minimate Plus Model). The absolute distances between shot points and monitor stations were determined using GPS. The equation of square root scaled distance extensively used in the literature was taken into consideration for the prediction of PPV. Then, the data pairs of scaled distance and particle velocity obtained from the 565 event records were analyzed statistically. At the end of statistical evaluation of the data pairs, an empirical relation which gives 50% prediction line with a reasonable correlation coefficient was established between PPV and scaled distance.

In this paper a method based on combining adaptive neuro fuzzy inference systems (ANFISs) and genetic algorithm (GA) is applied for design and optimization of a circularly polarized microstrip antenna for L1 frequency band of GPS. In design process, trained ANFISs are used for estimating return loss and axial ratio. In optimization process, a proper objective function is defined and minimized with GA in order to obtain optimum physical parameters. The optimization method is much faster than conventional optimization methods. Both simulation and measurement results confirm the accuracy and efficiency of the method.

The key issue of the localization study is that how we can minimize the energy consumption of devices with guaranteeing high degree of accuracy. In this paper, we show that the collaboration among proxy devices with short range communication is helpful to energy-efficiently localize their locations in time-average sense by analyzing the device proximity including real GPS trace of students in KAIST and NCSU campuses. Next, we deliberate what is the best method for selfish mobile users to collaborate for the energy-efficient localization, and formulate an optimization problem which considers the energy efficiency and/or user fairness. However, optimizing this problem is tricky since it requires a global knowledge of sets of proxy devices and also solving a NP-hard problem to select devices which directly measure locations. This paper makes a contribution towards presenting a practical and fully distributed location sharing protocol based on competition for turning off GPS, and an opt...

The increasing demand for up-to-date 3-D geographic information systems (GIS) in planning, transportation, and utility management applications poses significant challenges to the Geomatics community. Of all the challenges in acquiring, building, maintaining, and using GIS, none is more central than that of dala acquisition. Obtaining the required spatial and attribute data by conventional methods such as aerial photogrammetry and terrestrial surveying is expensive, slow, or inaccurate. These methods are, therefore, not well suited for rapid updating. Fortunately, however, the development of land-based mobile mapping systems (MMS) has opened a new avenue to meet these challenges. Land-based MMS are capable of providing fast, efficient, cost-effective and complete data acquisition. As such, they are an innovative technology for creating and updating 3-D GIS databases both quickly and inexpensively. Basically, MMS are based on integrated navigation systems, mainly the integration of GP...

This paper presents a GPS multipath mitigation method using a dual circularly polarized antenna array and a multi-channel receiver. The method is based on the exploitation of both polarization and spatial diversity associated with a GPS signal and its multipath signals available at the receiver input. Conventional GPS antennas are right-hand circularly polarized (RHCP) to suppress multipath contributions to the input. This polarization-based discrimination of multipath signal cannot completely eliminate multipath induced GPS range measurement errors. We present an algorithm that performs spatial processing on the input from the left-hand circular polarized (LHCP) array with an increased relative strength of the multipath signal, thereby providing improved multipath angle of arrival (AOA) estimation. With the known multipath AOA and direct signal AOA (which can be obtained from almanac/ephemeris together with the antenna attitude or estimated in a separate process), we can then take ...

In this study, the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) with three-dimensional variational data assimilation (3DVAR) is utilized to investigate influences of GPS occultation refractivity on simulations of typhoons past Taiwan. Two recent cases were simulated, including Typhoon Nari in September 2001 and Typhoon Nakri in July 2002. The GPS observation data are taken from the Challenging Minisatellite Payload for Geophysical Research and Application (CHAMP) and Satélite de Aplicaciones Científicas-C (SAC-C) satellites that provide several retrieved refractivity profiles in the simulated domain near the initialization time. Through 3DVAR, the observed refractivity can be quickly ingested into the model initial conditions to recover the information over the ocean. The initial moisture increments from ingested GPS refractivity soundings exhibit a maximum magnitude of about 1.5 g kg−1 associated with temperature incr...

The inequalities in the spatial distribution of infrastructural facilities have led to exclusion, poverty and lopsidedness in sustainable development. This is worsened by lack of reliable spatial and local data to plan for development issues. This paper employs the benefits of Participatory Geographical Information System to data collection and analysis for decision making in Community Driven Development at Upperland community, Ado- Ekiti in Nigeria. The data used for the study were collected through Participatory Rural Appraisal - Stakeholders' Analysis, Focus Group Discussion, Transect Walk and Voting- while ArcGIS 10.2.2 software was used for analysis such buffering. The results showed that the community people have indigenous spatial knowledge that development planners can rely upon. The study concludes that to have a sustainable community development, planners should tap into motivation, desire, knowledge and networks of local communities.

In this paper, we present the implementation of the acquisition algorithm of a versatile Global Navigation Satellite System (GNSS) receiver for satellite applications. For versatility purpose, the choice of the receiver algorithms has been motivated by 1) their capability to fulfill the application requirements with a moderate complexity, 2) their capability of being factorized in a small set of elementary modules that can be configured and combined in various ways in order to process both GPS and Galileo current and future signals. These algorithms have been specified using SystemC, a modeling language that can be common to hardware and software flow. The use of a virtual platform for simulation allows us to identify bottleneck of the architecture and to propose algorithm modification to solve them.

The growing demand for electricity makes the power grid ever expanding day by day and more and more complex. There is a potential requirement to continuously monitor the power grid and thus making it smarter and reliable. Traditional measurement systems are getting replaced by PMUs, which enables the online monitoring of the power system. With the aid of GPS, PMUs can measure the phasor values of voltages at the bus, where it is placed and the current through the branches connected to that bus. The Current measurement enables us to estimate the voltages at the neighbouring buses. Because of this, placing PMUs at all buses for the complete monitoring of the power system is redundant. Finding the optimal locations of PMUs to make the power system completely observable is of great research interest. This paper proposes the optimal locations of PMU in Tamil Nadu state of Indian power grid using ILP. PMU placement problem has been formulated and optimization has been carried out. Results showing the various optimal locations are tabulated.

LiDAR, typically used as an acronym for "'light detection and ranging'", is essentially a sonar that uses pulsed laser waves to map the distance to surrounding objects. It is used by a large number of autonomous vehicles to navigate environments in real time. Its advantages include impressively accurate depth perception, which allows LiDAR to know the distance to an object to within a few centimetres, up to 60 metres away. It's also highly suitable for 3D mapping, which means returning vehicles can then navigate the environment predictably-a significant benefit for most self-driving technologies. One of the key strengths of LiDAR is the number of areas that show potential for improvement. These include solid-state sensors, which could reduce its cost tenfold, sensor range increases of up to 200m, and 4-dimensional LiDAR, which senses the velocity of an object as well as its position in 3-D space. However, despite these exciting advances, LiDAR is still hindered by a key factor; its significant cost. LiDAR is not the only self-driving detection technology, with cameras as the major rival, championed by Tesla as the best way forward. Elon Musk has described LiDAR as "a fool's errand" and "unnecessary". The argument runs that humans drive based only on ambient visible light, so robots should equally be able to. A camera is significantly smaller and cheaper than LiDAR (although more of them are needed), and has the advantage of seeing in better resolution and in colour, meaning it can read traffic lights and signs. However, cameras have a wide host of characteristics that make them tricky to use in common driving conditions. Whereas LiDAR uses near infra-red light, cameras use visible light, and are thus more susceptible to issues when faced with rain, fog, or even some textures. In addition, LiDARs do not depend on ambient light, generating their own light pulses, whereas cameras are more sensitive to sudden light changes, direct sunlight and even raindrops.

The use of GPS for the estimation of orthometric heights in a given region, with the help of existing levelling data requires the determination of a local geoid and the bias between the local levelling and the one implicitly defined when the geoid is calculated which is generally based on the gravity anomalies data. The heights of new data can