Process control for laser materials processing

Examples of process monitoring and real time process control are given. Considering industrial applications, methods for the detection of process signals are integrated into the beam path to provide free access to the workpiece without being blocked by the diagnostic tools. When carrying out industrial applications, it is necessary to detect process signals independent of workpiece geometry and characteristics of the handling system. The application of the diagnostic methods and devices presented in this paper enables to detect the process in all laser machining processes. The possibilities of process control are demonstrated in case of welding. A sensor/actuator field bus network allows it to collect and analyze a lot of sensor signals to facilitate extensive on line process control with the greatest possible autonomy and self-calibration of the processing system

Privacy-Preserving Power Usage Control in the Smart Grid

Part 3: INFRASTRUCTURE SECURITYInternational audienceIn the smart grid, the power usage of households are recorded and analyzed in (near) real time by utility companies. The usage data enables a utility to manage its electric power supply to neighborhoods more efficiently and effectively. For instance, to prevent a power outage during a peak demand period, the utility can determine the power supply threshold for a neighborhood. When the total power usage of the neighborhood exceeds the threshold, certain households in the neighborhood are required to reduce their energy consumption. This type of power usage control benefits electric utilities and their consumers. However, the energy usage data collected by a utility can also be used to profile an individual’s daily activities – a potentially serious breach of personal privacy. To address the problem, this paper specifies distributed, privacy-preserving energy usage control protocols that enable utilities to efficiently manage power distribution while ensuring that individual power usage data is not revealed