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Unobtrusive sleep monitoring in children presents challenges. We investigated the possibility of using an ultra-wide band (UWB) radar to measure sleep in children. Tested on 32 children undergoing a clinical polysomnography, the use of 38 features extracted from radar signals and an adaptive boosting algorithm led to promising results in estimating sleep stages.

NFPA 70E-2018 requires arc flash incident energy analysis to be updated when changes occur in the electrical power distribution system and the analysis shall be reviewed for accuracy at least every five years. NFPA-70E-2018 also requires data used for creating equipment labels, which contain arc flash energy information, to be reviewed at least every five years and, if the review identifies a change that renders the arc flash energy label inaccurate, the equipment label must be updated.The challenge for consultants and end users is to determine how much of a data review is required. NFPA 70E does not address this specific issue. For a small facility with only a few substations, the entire system model can be reviewed without too much work. For large facilities with many substations, a complete review of the entire system could take a year, which would be costly or a large burden on resources. In this paper, the authors will provide suggested guidelines for performing the five-year review. The authors provide their recommended arc flash incident energy analysis renewal approach that would help ensure the system labeling can be updated appropriately while allowing the model to be reviewed and updated in a reasonable amount of time.

For more than 50 years, IEEE Industry Applications Society (IAS) members have been at the forefront of pioneering leadership in advancing knowledge of arcing faults and the application of practical measures to protect people from thermal and blast hazards inherent in electric power systems. This article highlights some of the key milestones in this evolution and recognizes the IAS members who made pioneering contributions in this field.

In recent years, engineers have been redesigning the protection schemes for electrical installations to reduce the arc flash hazard associated with switching and maintaining equipment. For electrical fire pumps, however, NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, prescribes very strict requirements for reliability of the power feed and overcurrent protection for an electric fire pump. The result is that current is allowed to flow for a longer time period to ensure that a fire pump may start without nuisance tripping. These requirements are made without consideration for the associated arc flash hazard. These requirements do not acknowledge that a redundant fire pump installation can provide equal or greater system reliability, plus greater operator safety, than possible with a potentially hazardous "reliable" power feed to a single fire pump. This paper will summarize reliability requirements currently mandated for electric fire pumps, discuss the arc flash impact of those requirements, and propose language that could be incorporated in future code revisions to reduce safety hazards while preserving operating reliability of system installations