51 research outputs found

    Model of geosensor network for real-time monitoring of terrain and objects

    Get PDF
    Praćenje promena, odnosno, monitoring terena i objekata je zadatak od izuzetnog značaja, jer omogućava, u prvom redu, pravovremeno reagovanje i time smanjenje materijalne štete i ljudskih žrtava. Primena modernih tehnologija u oblasti senzora i komunikacija obezbeđuje monitoring terena i objekata u realnom vremenu. Prostorno distribuirani senzori – geosenzorska mreža, prikupljaju podatke, koji se na računarima skladište i analiziraju. Disertacija se bavi modelom geosenzorske mreže, kao opštim rešenjem za monitoring terena i objekata, koje predstavlja polaznu osnovu od koje se može doći do sistema koji zadovoljava postavljene zahteve.Observing of changes, that is, monitoring of terrain and objects, is very significant task, since it enables timely response and thus decreasing of material damage and human casualties. Usage of modern sensor and communication technologies provides real-time monitoring of terrain and objects. Spatialy distributed sensors, i.e. geosensor network, gather the data which are then stored and analyzed. In this disertation a model of geosensor network is proposed as a generalized solution for monitoring of terrain and objects which can represent a basis in creating a system that can be altered to meet the requirements in certain cases

    Generalized Model of Real-Time Deformation Measurements and its Experimental Verification

    Get PDF
    Technology development enabled real-time monitoring of terrain and artificial structures through the use of the systems comprised of geodetic and geotechnical sensors. Although the structure and the architecture of those systems can vary, they have many common features: automated measurements which provide monitoring and alarming when tolerances are exceeded, systems robustness involving hot-swapping sensors, its redundancy and error detection. Also, they can be structured and configured to achieve desired functionality and performance. Generalized model of real-time deformation measurements, presented in this paper, involves these common characteristics. The model is presented as a flowchart, and later applied within an experiment carried out in laboratory environment. The established system includes geodetic and geotechnical sensors and measurements are done on a physical model of a landslide. Several functions included in generalized model were implemented in the experiment. Results show that system designed using the proposed model can provide required functionality, accuracy, robustness and configurability. Aim of the paper is to propose a general procedure which, with minor modifications, can be applied as a starting point in designing various systems for monitoring landslides, bridges, high buildings etc., and which overcomes some limitations that can be found in commercial software solutions

    Comparative analysis of the ellipsoid approximation with the sphere

    Get PDF
    The paper analyzes the approximation of the ellipsoid by the sphere. Earth is a space body with a mathematically irregular shape, so idealized smooth surfaces are used for calculations. The first is the geoid, a smooth, equipotential surface that best approximates mean sea level. However, the geoid does not have an analytical form and is unsuitable for many applications, so an ellipsoid is used for approximation. In applications where high accuracy is not required (e.g., with small scale maps), the ellipsoid is approximated by a sphere. The radius of the sphere can be calculated in three ways: according to the equivalent volume criterion, according to the equivalent surface criterion, or as the mean value of the three semi-axes of the ellipsoid. All three methods of approximation were tested by calculating the length of the geodetic line on the ellipsoid, the orthodrome on the spheres and then the error. Also, the influence of latitude on the error value was tested. For three different values of geographic latitude, the lengths of geodetic lines up to one hundred points were calculated (using the Bessel method for solving the second main geodetic task on the ellipsoid), as well as the lengths of the orthodromes on the spheres, with the radii of the spheres determined in the three mentioned ways. The obtained results were then analyzed and discussed

    On the introduction of canny operator in an advanced imaging algorithm for real-time detection of hyperbolas in ground-penetrating radar data

    Get PDF
    This paper focuses on the use of the Canny edge detector as the first step of an advanced imaging algorithm for automated detection of hyperbolic reflections in ground-penetrating radar (GPR) data. Since the imaging algorithm aims to work in real time; particular attention is paid to its computational efficiency. Various alternative criteria are designed and examined, to fasten the procedure by eliminating unnecessary edge pixels from Canny-processed data, before such data go through the subsequent steps of the detection algorithm. The effectiveness and reliability of the proposed methodology are tested on a wide set of synthetic and experimental radargrams with promising results. The finite-difference time-domain simulator gprMax is used to generate synthetic radargrams for the tests, while the real radargrams come from GPR surveys carried out by the authors in urban areas. The imaging algorithm is implemented in MATLAB

    Preliminary Analysis of Quality of Contour Lines Using Smoothing Algorithms

    Get PDF
    In this paper several well-known filtering techniques were compared in the purpose of automatic line generalization. The used methods for line simplification are digital first order low-pass filter, Savitzky-Golay (SG) filter and Whittaker filter. Two versions of the algorithm for line feature generalization were tested, from source scale 1:25 000 towards target scale of 1:100 000 and from source scale 1:25 000 towards scale of 1:50 000. Also, GPS data filtering for the target scale 1:50 000 was tested. The first version of the algorithm considers that there are no control data, and the filtering parameter is dictated by the desired accuracy for the target scale. The second version involves control data in the target scale. This means that the optimal value for the filtering parameter is the value for which the difference between input and control data is the smallest. Analysis showed that the SG filter yielded the best results in general. The proposed filters can be considered as a new solution for automated cartographic line simplification

    Asheville: Resilience through Leadership, Partnerships and Diversity

    Get PDF
    Asheville’s ability to rebuild itself and to foster a vibrant downtown in the second half of the 20th century owes much to its early history. Asheville was a booming town in 1900, an urban center for the mountain area with numerous trading-related businesses. The completion of the railway line to Asheville in 1880 had ushered in a period of increased tourism and development. By the turn of the century, the area hosted a number of health sanitariums that attracted people from far and wide. It was marketed as a beautiful place where people could rest, renew, relax, and recover from illnesses. Ever since this time, tourism has played an important and growing role in Asheville’s economy

    Functional Magnetic Resonance Imaging of Motor Cortex Activation in Schizophrenia

    Get PDF
    Previous fMRI studies of sensorimotor activation in schizophrenia have found in some cases hypoactivity, no difference, or hyperactivity when comparing patients with controls; similar disagreement exists in studies of motor laterality. In this multi-site fMRI study of a sensorimotor task in individuals with chronic schizophrenia and matched healthy controls, subjects responded with a right-handed finger press to an irregularly flashing visual checker board. The analysis includes eighty-five subjects with schizophrenia diagnosed according to the DSM-IV criteria and eighty-six healthy volunteer subjects. Voxel-wise statistical parametric maps were generated for each subject and analyzed for group differences; the percent Blood Oxygenation Level Dependent (BOLD) signal changes were also calculated over predefined anatomical regions of the primary sensory, motor, and visual cortex. Both healthy controls and subjects with schizophrenia showed strongly lateralized activation in the precentral gyrus, inferior frontal gyrus, and inferior parietal lobule, and strong activations in the visual cortex. There were no significant differences between subjects with schizophrenia and controls in this multi-site fMRI study. Furthermore, there was no significant difference in laterality found between healthy controls and schizophrenic subjects. This study can serve as a baseline measurement of schizophrenic dysfunction in other cognitive processes

    THE PSYCHOMOTOR THEORY OF HUMAN MIND

    Full text link

    An analog-to-digital converter for on-line use in response dynamics research

    No full text
    corecore