Network and System Management for the Security Monitoring of Microgrids using IEC 62351-7

Interest in adding renewable energy sources to the power grid has risen substantially in recent years. As a response to this growing interest, the deployment of microgrids capable of integrating renewable energy has become more widespread. Microgrids are independent power systems that deliver power from different kinds of Distributed Energy Resources (DERs) to local energy consumers more efficiently than the conventional power grid. The microgrid leverages advanced information and communication technologies for vital protection, monitoring, and control operations as well as for energy management. With the use of information technology comes the need to protect the microgrid information layer from cyberattacks that can impact critical microgrid power operations. In this research, a security monitoring system to detect cyberattacks against the microgrid, in near-real time, is designed and implemented. To achieve this, the system applies Network and System Management (NSM) for microgrid security monitoring, as specified by the IEC 62351-7 security standard for power systems. The specific contributions of this research are (i) an investigation on the suitability of NSM for microgrid security monitoring; (ii) the design and implementation of an NSM platform; (iii) the design and implementation of a security analytics framework for NSM based on deep learning models; (iv) the elaboration of a comprehensive microgrid simulation model deployed on a Hardware in the Loop (HIL) co-simulation framework; and (v) an experimental evaluation on the effectiveness and scalability of the NSM security monitoring platform for detection against microgrid attack scenarios, with a methodology being used to systematically generate the scenarios. The experimental results validate the usefulness of NSM in detecting attacks against the microgrid

Impacts of dissolved oxygen on the sorption of humic substances and the subsequent inhibition of o-cresol ptake by granular activated carbon

The impacts of dissolved oxygen (DO) on the sorption of natural and model humic substances by granular activated carbon (GAC) were investigated. Among five substances tested, the sorptions of only two, polymaleic acid (PMA) and peat humic acid, were affected by the presence of DO. The uptake of the target compound o-cresol on virgin GAC and on GAC preloaded with PMA under oxic and anoxic conditions was also examined. The oxic and anoxic preloading conditions had similar effects on subsequent o-cresol reactions under both oxic and anoxic sorption conditions. A reduction of approximately 20 % in o-cresol uptake observed under anoxic conditions by GAC preloaded under each condition is attributed to a decrease in the adsorption capacity of the GAC by preloading. In the presence of oxygen, however, an observed reduction of about 45% in o-cresol uptake by preloaded GAC appears to result from a combination of decreased adsorption and inhibited o-cresol polymerization.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31488/1/0000410.pd

The Impact of Filtrate Turbidity on UV254 and SUVA254 Determinations

UV254 and SUVA254 determinations are used in water treatment to obtain information about the nature of dissolved organic carbon (DOC) in water samples. This article presents new information about obtaining accurate results for UV254 and SUVA254 (the ratio of UV254 to the concentration of DOC in the water) in freshwater samples. Although the potential impact of colloidal materials on UV254 results is mentioned in standard and US Environmental Protection Agency methods, these methods provide no clear guidance for validating such measurements. The main objectives of this research were to examine the effects of colloidal and particulate matter in freshwaters on DOC and UV254 determinations and to develop some guidelines for filtering freshwater samples with widely varying turbidities. The experimental results showed that the water sample turbidity level and characteristics as well as the nature of the membrane filter pore structures and pore size distribution play important roles in UV254 and SUVA254 determinations. Measuring turbidity in the sample filtrate was a simple way to validate UV254 and SUVA254 results. The findings of this study will help the water treatment industry obtain more reliable UV254 and SUVA254 results and assist in developing improved experimental protocols

Serotyping Pneumococcal Meningitis Cases in the African Meningitis Belt by Use of Multiplex PCR with Cerebrospinal Fluid▿

We reformulated a multiplex PCR algorithm for serotyping of pneumococcal meningitis directly on cerebrospinal fluid (CSF). Compared to established methods on isolates, CSF-based PCR had at least 80% sensitivity and 100% specificity. In regional meningitis surveillance, CSF-based PCR increased the serotype information yield from 40% of cases (isolate testing) to 90%