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Hadley, Mark D

Publications and source records attributed to Hadley, Mark D.

A Multi-layer, Hierarchical Information Management System for the Smart Grid

This paper presents the modeling approach, methodologies, and initial results of setting up a multi-layer, hierarchical information management system (IMS) for the smart grid. The IMS allows its users to analyze the data collected by multiple control and communication networks to characterize the states of the smart grid. Abnormal, corrupted, or erroneous measurement data and outliers are detected and analyzed to identify whether they are caused by random equipment failures, unintentional human errors, or deliberate tempering attempts. Data collected from different information networks are crosschecked for data integrity based on redundancy, dependency, correlation, or cross-correlations, which reveal the interdependency between data sets. A hierarchically structured reasoning mechanism is used to rank possible causes of an event to aid the system operators to proactively respond or provide mitigation recommendations to remove or neutralize the threats. The model provides satisfactory performance on identifying the cause of an event and significantly reduces the need of processing myriads of data collected.

99 GENERAL AND MISCELLANEOUS↗

The Development of a Smart Distribution Grid Testbed for Integrated Information Management Systems

This paper presents a smart distribution grid testbed to test or compare designs of integrated information management systems (I2MSs). An I2MS extracts and synthesizes information from a wide range of data sources to detect abnormal system behaviors, identify possible causes, assess the system status, and provide grid operators with response suggestions. The objective of the testbed is to provide a modeling environment with sufficient data sources for the I2MS design. The testbed includes five information layers and a physical layer; it generates multi-layer chronological data based on actual measurement playbacks or simulated data sets produced by the physical layer. The testbed models random hardware failures, human errors, extreme weather events, and deliberate tampering attempts to allow users to evaluate the performance of different I2MS designs. Initial results of I2MS performance tests showed that the testbed created a close-to-real-world environment that allowed key performance metrics of the I2MS to be evaluated.

99 GENERAL AND MISCELLANEOUS↗

Home Area Networks and the Smart Grid

With the wide array of home area network (HAN) options being presented as solutions to smart grid challenges for the home, it is time to compare and contrast their strengths and weaknesses. This white paper examines leading and emerging HAN technologies. The emergence of the smart grid is bringing more networking players into the field. The need for low consistent bandwidth usage differs enough from the traditional information technology world to open the door to new technologies. The predominant players currently consist of a blend of the old and new. Within the wired world Ethernet and HomePlug Green PHY are leading the way with an advantage to HomePlug because it doesn't require installing new wires. In the wireless the realm there are many more competitors but WiFi and ZigBee seem to have the most momentum.

99 GENERAL AND MISCELLANEOUS↗