In recent years, the measurement of dam displacements has benefited from a great improvement of existing technology, which has allowed a higher degree of automation. This has led to data collection with an improved temporal and spatial resolution. Robotic total stations and GNSS (Global Navigation Satellite System) techniques, often in an integrated manner, may provide efficient solutions for measuring 3D displacements on precise locations on the outer surfaces of dams. On the other hand, remote-sensing techniques, such as terrestrial laser scanning, ground-based SAR (synthetic aperture radar) and satellite differential interferometric SAR offer the chance to extend the observed region to a large portion of a structure and its surrounding areas, integrating the information that is usually provided in a limited number of in-situ control points. The design and implementation of integrated monitoring systems have been revealed as a strategic solution to analyze different situations in a spatial and temporal context. Research devoted to the optimization of data processing tools has evolved with the aim of improving the accuracy and reliability of the measured deformations. The analysis of the observed data for the interpretation and prediction of dam deformations under external loads has been largely investigated on the basis of purely statistical or deterministic methods. The latter may integrate observation from geodetic, remote-sensing and geotechnical/structural sensors with mechanical models of the dam structure. In this paper, a review of the available technologies for dam deformation monitoring is provided, including those sensors that are already applied in routinary operations and some experimental solutions. The aim was to support people who are working in this field to have a complete view of existing solutions, as well as to understand future directions and trends.

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Geodetic and Remote-Sensing Sensors for Dam Deformation Monitoring.

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Integration of a mobile autonomous robot in a surveillance multi-agent system

We present a comprehensive review of several variometric tests recently carried out on a home-made measurement system composed of a tern of low-cost accelerometer sensors of MEMS (Micro-Electro-Mechanical Systems) type equipped with autonomous electric supply and wireless transmission. The most important parameters characterizing the systematic errors, i.e. bias, scale factor and thermal correction factor, have been evaluated by calibration tests based upon the so-called “six -positions” static test proposed by the IEEE 517 Standard. In this way the system optimal configuration has been defined in terms of data acquisition frequency and of scale factor. In addition to such tests, partly documented elsewhere, the results of some sensitivity tests on the influence of external environmental factors are also presented. With the aim of employing the proposed MEMS-based system as a device for monitoring the onset of slope landslides, some further tests have been carried out in order to measure the inclination of rigid objects which the sensors have been fixed to. The most significant results of the tests are illustrated and discussed.

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Variometric tests for accelerometer sensors

This paper attempts to define a name for an area of science and technology that encompasses the acquisition, processing and application of spatial data in the mining industry. A comparative study of the evolution of spatial data exchange methods between Geographic Information Systems (GISs) and General Mining Planning (GMP) software is carried out to define the problem and name it. Subsequent modifications of the acronym GIS towards the specialisation of its application in mining are then reviewed. This is followed by the identification of three terminological postulates designed to formulate constraints and rules for the creation of a new definition. The subsequent analysis identifies the nomenclatural basis of the research area of geomatics and determines its applicability in the context of mining. The results of the research made it possible to formulate a new definition of “mining geomatics”. The final section of the article presents an initial proposal for an inventory of the basic concepts of mining geomatics in the form of a Body of Knowledge for mining geomatics.

Mining Geomatics

We are at a time of transition in the fields of planetary geodesy, mapping, and imaging. Planetary exploration has moved from a time of initial reconnaissance of the solar system using mostly planetary flyby missions and images exclusively from framing cameras to much more extensive missions of targeted exploration using orbiting spacecraft, line-scanner cameras, laser altimeters, and other sensors. It is appropriate to review the past history of this effort, recent advances in this area, and the current state of the art in both planetary and terrestrial geodesy, mapping, planetary imaging and surveillance, and reference systems. A wireless sensor network is a network consisting of small sensing devices spatially distributed using sensors to cooperatively monitor various conditions (Romer and Mattern, IEEE Wireless Comm 11(6):54–61, 2004; Thomas Haenselmann, Sensornetworks, GFDL Wireless Sensor Network textbook, http://www.informatik.uni-mannheim.de/∼haensel/sn_book, 2006). So far, over 100 physical (light, pressure, humidity, etc.), chemical (gas, liquid, solid, etc.), and biological (DNA, protein, acoustics, etc.) properties can be sensed by using in situ sensing technology. With the presence of cheaper, miniature, faster, and smart in situ sensors, the increasing availability of abundant ubiquitous computing devices, wireless and mobile network access, and autonomous and intelligent geospatial software agents, distributed networked in situ sensing becomes clearly a technological trend. Sensor Webs can perform as an extensive monitoring and sensing system that provides timely, comprehensive, continuous, and multi-mode observations on underground mining, wildlife, and various physical infrastructures such as bridges, pipelines, and buildings. These new earth-observation systems open up new avenues to fast assimilation of data from various sensors (both in situ and remote) and to accurate analysis and informed decision-makings. This paper studies the security aspects and present and future applications of these networks. The paper first introduces the revolutionary concept of the Sensor Web and provides a comprehensive study of Sensor Web (both Sensor Web and sensors mean the same), and then presents its related security problems, threats, risks, and characteristics. Additionally, the paper gives a brief introduction to the application and the opportunities available for these networks in rural India and thereby provides an opportunity to improve the quality of life which is integrated with that of domestic animal health, soil and water quality, and plant/crop health. We examine the possibility of setting up of sensor networks to monitor these aspects so as to provide a detailed set of information to the residents as well as planners.

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Ravish Khichar

Papers

Wireless sensor networks and their applications in geomatics: case study on developments in developing countries