9 research outputs found

    Application framework for wireless sensor networks [thesis]

    Get PDF
    Wireless Sensor Networks (WSNs) are based on innovative technologies that had revolutionized the methods in which we interact with the environment; i.e., through sensing the physical (e.g., fire motion, contact) and chemical (e.g., molecular concentration) properties of the natural surroundings. The hardware in which utilized by WSNs is rapidly evolving into sophisticated platforms that seamlessly integrate with different vendors and protocols (plug-n-play). In this thesis, we propose a WSN framework which provides assistance with monitoring environmental conditions; we focus on three main applications which include: a. Air-quality monitoring, b. Gas-leak detection, and c. Fire sensing. The framework involves four specifications: 1. Over the air programming (OTAP), 2. Network interconnections, 3. Sensors manageability, and 4. Alarm signaling. Their aim is to enhance the internetwork relations between the WSNs and the outside-world (i.e., main users, clients, or audience); by creating a medium in which devices efficiently communicate, independent of location or infrastructure (e.g., Internet), in order to exchange data among networked-objects and their users. Therefore, we propose a WSN-over-IP architecture which provides several renowned services of the Internet; the major functionalities include: live-data streaming (real-time), e-mailing, cloud storage (external servers), and network technologies (e.g., LAN or WLAN). WSNs themselves operate independently of the Internet; i.e., their operation involve unique protocols and specific hardware requirements which are incompatible with common network platforms (e.g., within home network infrastructure). Hybrid technologies are those which support multiple data-communication protocols within a single device; their main capabilities involve seamless integration and interoperability of different hardware vendors. We propose an overall architecture based on hybrid communication technology in which data is transmitted using three types of protocols: 802.11 (Wi-Fi), 802.15.4 and Digimesh (WSN)

    Remote beehive monitoring using acoustic signals

    Get PDF
    Recent developments in Wireless Sensor Networks (WSNs) have led to their use in remote data acquisition and automatic data analysis applications, which have proven to be an invaluable tool in a diverse range of fields including biosecurity. Further indications have been found that honeybee health can be monitored and determined through the use of acoustic analysis. In this paper, we present a system that has the ability to remotely detect the presence of pest infestation on a colony of honeybees by comparing the acoustic fingerprint of a hive to a fingerprint of known status. This will aid the goals of increasing surveillance programs by reducing the labour time and costs that are associated with managing and maintaining monitoring programs. Other benefits of the system proposed in this article include the ability to make available a collection of deterministic, standardised and nondiscriminatory statistical data for the purpose of research into determining the causes of colony collapse disorder

    Comparison of STPA and Bow-tie Method Outcomes in the Development and Testing of an Automated Water Quality Management System

    Get PDF
    The technology available to water quality management applications needs to be advanced due to greater use of automation to increase ease of operation, support remote operation and reduce risks due to operator error. In this case study, a comparison is made between System-Theoretic Process Analysis (STPA) and the Bow-tie methodology for identifying process hazards and countermeasures which can be used to guide the design and testing of an automated water quality management system (AWQMS). For this study, the application considered is a small hydroponics installation where water quality management has been automated. The STPA methodology uses a system theory-based approach to identify hazards, which include operational failures, human errors, and component interactions. The Bow-tie diagram focuses on individual barriers for a given threat which can prevent the realisation of a hazardous event and unwanted consequences. Thus, the 22 preventative barriers and seven recovery barriers identified through the Bow-tie diagram provide the design process with broad requirements for reducing the risks of user error as well as the ones associated with ongoing operations. The STPA method identified many Causal Factors (CF) generated from the Unsafe Control Actions after considering all the feasible scenarios. For design input, the STPA provided the design process with 204 specific CFs which were used to create 94 countermeasures to be included in software and hardware design as well as user information material. Both methods identified useful measures to control the hazards associated with human interaction with the AWQMS. However, the measures differed in the level of detail and the involvement in the evolution in the final system losses. In this study, the STPA process was able to identify several hazards which did not visibly relate to the Bow-tie barriers. However, the Bow-tie diagram illustrates a distinction between preventative and recovery hazard controls

    Comparison of STPA and Bow-tie Method Outcomes in the Development and Testing of an Automated Water Quality Management System

    No full text
    The technology available to water quality management applications needs to be advanced due to greater use of automation to increase ease of operation, support remote operation and reduce risks due to operator error. In this case study, a comparison is made between System-Theoretic Process Analysis (STPA) and the Bow-tie methodology for identifying process hazards and countermeasures which can be used to guide the design and testing of an automated water quality management system (AWQMS). For this study, the application considered is a small hydroponics installation where water quality management has been automated. The STPA methodology uses a system theory-based approach to identify hazards, which include operational failures, human errors, and component interactions. The Bow-tie diagram focuses on individual barriers for a given threat which can prevent the realisation of a hazardous event and unwanted consequences. Thus, the 22 preventative barriers and seven recovery barriers identified through the Bow-tie diagram provide the design process with broad requirements for reducing the risks of user error as well as the ones associated with ongoing operations. The STPA method identified many Causal Factors (CF) generated from the Unsafe Control Actions after considering all the feasible scenarios. For design input, the STPA provided the design process with 204 specific CFs which were used to create 94 countermeasures to be included in software and hardware design as well as user information material. Both methods identified useful measures to control the hazards associated with human interaction with the AWQMS. However, the measures differed in the level of detail and the involvement in the evolution in the final system losses. In this study, the STPA process was able to identify several hazards which did not visibly relate to the Bow-tie barriers. However, the Bow-tie diagram illustrates a distinction between preventative and recovery hazard controls
    corecore