Def Stan 00-56 requires a safety case to be built before an autonomous system can be certified, but there is no current guidance on how such a case should be structured. The authors have reviewed several plausible app...
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Def Stan 00-56 requires a safety case to be built before an autonomous system can be certified, but there is no current guidance on how such a case should be structured. The authors have reviewed several plausible approaches to structuring a safety case, including arguing human equivalence, deriving necessary capabilities from a level of autonomy scheme, and by deriving an explicit rationale for the unmanned systems safety guide recently published by the US Department of Defense. From this, we have produced an initial recommended approach. The process of deriving it has revealed that much of the published advice on autonomous system safety is either of very low value or potentially dangerous.
The seismic design of a nuclear power plant includes two levels of design earthquake, the safe shutdown earthquake (SSE) and the operating basis earthquake (OBE). The OBE and SSE are considered in the nuclear power pl...
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The seismic design of a nuclear power plant includes two levels of design earthquake, the safe shutdown earthquake (SSE) and the operating basis earthquake (OBE). The OBE and SSE are considered in the nuclear power plant design as required by the IAEA safety regulations. A typical piping model for the ETRR-2 core cooling system includes ASME-class 1, 2 and 3 piping and was analyzed with regard to both IAEA safety regimes. A load combination, as stated by the IAEA safety Guide 50-SG-S2, has been considered. The safety guide requires that the OBE should equal to at least one half SSE and that the plant should be shut down if exposed to earthquake intensity greater than the OBE. The results reflect the requirement for the precise design of a supporting system to accommodate for higher seismic peaks more than 0.2 g and the system needs to be more flexible.
Surface-temperature elevation of the wrist and the ankle sections were measured for a healthy human subject at room temperature (22-25 degrees C) for a variety of RF currents and SARs (specific absorption rate) in the...
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Surface-temperature elevation of the wrist and the ankle sections were measured for a healthy human subject at room temperature (22-25 degrees C) for a variety of RF currents and SARs (specific absorption rate) in the frequency band 1-50 MHz. The observed highest rates of temperature increase in degrees C/min are given by the best-fit relationships: 0.0045*SAR in W/kg for the ankle section and 0.0048*SAR for the wrist section, the latter being involved for conditions of contact with ungrounded bodies like cars, trucks, fences, etc. Since ankle-section SARs on the order of 182-243 W/kg and wrist-section SARs as high as 1045 W/kg have previously been projected for the E fields recommended in the ANSI C95.1-1982 safety guide, fairly high rates of temperature increase are anticipated.
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