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Design and Development of a Passive Infra-Red-Based Sensor Platform for Outdoor DeploymentUpadrashta, Raviteja January 2017 (has links) (PDF)
This thesis presents the development of a Sensor Tower Platform (STP) comprised of an array of Passive Infra-Red (PIR) sensors along with a classification algorithm that enables the STP to distinguish between human intrusion, animal intrusion and clutter arising from wind-blown vegetative movement in an outdoor environment. The research was motivated by the aim of exploring the potential use of wireless sensor networks (WSNs) as an early-warning system to help mitigate human-wildlife conflicts occurring at the edge of a forest.
While PIR sensors are in commonplace use in indoor settings, their use in an outdoor environment is hampered by the fact that they are prone to false alarms arising from wind-blown vegetation. Every PIR sensor is made up of one or more pairs of pyroelectric pixels arranged in a plane, and the orientation of interest in this thesis is one in which this plane is a vertical plane, i.e., a plane perpendicular to the ground plane. The intersection of the Field Of View (FOV) of the PIR sensor with a second vertical plane that lies within the FOV of the PIR sensor, is called the virtual pixel array (VPA). The structure of the VPA corresponding to the plane along which intruder motion takes place determines the form of the signal generated by the PIR sensor. The STP developed in this thesis employs an array of PIR sensors designed so as to result in a VPA that makes it easier to discriminate between human and animal intrusion while keeping to a small level false alarms arising from vegetative motion. The design was carried out in iterative fashion, with each successive iteration separated by a lengthy testing phase. There were a total of 5 design iterations spanning a total period of 14 months.
Given the inherent challenges involved in gathering data corresponding to animal intrusion, the testing of the SP was carried out both using real-world data and through simulation. Simulation was carried out by developing a tool that employed animation software to simulate intruder and animal motion as well as some limited models of wind-blown vegetation. More specifically, the simulation tool employed 3-dimensional models of intruder and shrub motion that were developed using the popular animation software Blender. The simulated output signal of the PIR sensor was then generated by calculating the area of the 3-dimensional intruder when projected onto the VPA of the STP. An algorithm for efficiently calculating this to a good degree of approximation was implemented in Open Graphics Library (OpenGL). The simulation tool was useful both for evaluating various competing design alternatives as well as for developing an intuition for the kind of signals the SP would generate without the need for time-consuming and challenging animal-motion data collection.
Real-world data corresponding to human motion was gathered on the campus of the Indian Institute of Science (IISc), while animal data was recorded at a dog-trainer facility in Kengeri as well as the Bannerghatta Biological Park, both located in the outskirts of Bengaluru. The array of PIR sensors was designed so as to result in a VPA that had good spatial resolution. The spatial resolution capabilities of the STP permitted distinguishing between human and animal motion with good accuracy based on low-complexity, signal-energy computations. Rejecting false alarms arising from vegetative movement proved to be more challenging. While the inherent spatial resolution of the STP was very helpful, an alternative approach turned out to have much higher accuracy, although it is computationally more intensive. Under this approach, the intruder signal, either human or animal, was modelled as a chirp waveform. When the intruder moves along a circular arc surrounding the STP, the resulting signal is periodic with constant frequency. However, when the intruder moves along a more likely straight-line path, the resultant signal has a strong chirp component. Clutter signals arising from vegetative motion does not exhibit this chirp behavior and an algorithm that exploited this difference turned in a classification accuracy in excess of 97%.
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Návrh zabezpečovacího systému areálu společnosti / A Proposal for a Security System of the Company PremisesČerný, Jan January 2014 (has links)
The content of this thesis is the complex security system proposal, specifically of PZTS system and CCTV system. The thesis is divided into three parts. The first part is analysis of the current state, the second is theoretical part and the third part is a practical part. The first part deals with the analysis of the current state of physical security and technical protection of the premises. The theoretical part deals with theoretical solutions for security system proposal. The practical part is focused on separate PZTS and CCTV systems proposal, that will meet all the requirements and standards of the customer.
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Návrh a analýza systémů pokročilého zabezpečení a střežení objektů a prostor / Design and Analysis of Systems for Advanced Guarding and Securing Objects and AreasKomínek, Petr January 2011 (has links)
This diploma thesis deals with design, realization and analysis of security and surveillance systems for buildings and spaces containing advanced components. One of the main design's parts is dedicated to intruder alarm system, access system, attendance and CCTV systems with the possibility of automatic motion tracking. Controlling and monitoring of particular subsystems is possible both locally and remotely from a computer via a web interface or by means of a software. The access to camera system from a mobile phone is also possible. IAS/ACS systems also enable controlling and transferring information about their state via SMS. The designed system was realized completely and its operating was demonstrated. The realization is described in detail including illustration of configuration of particular components. A security analysis and a possible future development of the project is summarized in the conclusion.
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