Majority and Minority Voted Redundancy for Safety-Critical Applications

A new majority and minority voted redundancy (MMR) scheme is proposed that can provide the same degree of fault tolerance as N-modular redundancy (NMR) but with fewer function units and a less sophisticated voting logic. Example NMR and MMR circuits were implemented using a 32/28nm CMOS process and compared. The results show that MMR circuits dissipate less power, occupy less area, and encounter less critical path delay than the corresponding NMR circuits while providing the same degree of fault tolerance. Hence the MMR is a promising alternative to the NMR to efficiently implement high levels of redundancy in safety-critical applications

Kinetics of CO<inf>2</inf>-fluid-rock reactions in a basalt aquifer, Soda Springs, Idaho

The dissolution of silicate minerals by CO2–rich fluids and the subsequent precipitation of CO2 as carbonate minerals represent a means of permanently storing anthropogenic CO2 waste products in a solid and secure form. Modelling the progression of these reactions is hindered by our poor understanding of the rates of mineral dissolution-precipitation reactions and mineral surface properties in natural systems. This study evaluates the chemical evolution of groundwater flowing through a basalt aquifer, which forms part of the leaking CO2-charged system of the Blackfoot Volcanic Field in south-eastern Idaho, USA. Reaction progress is modelled using changes in groundwater chemistry by inverse mass balance techniques. The CO2-promoted fluid-mineral reactions include the dissolution of primary plagioclase, orthoclase, pyroxene and gypsum which is balanced by the precipitation of secondary albite, calcite, zeolite, kaolinite and silica. Mineral mole transfers and groundwater flow rates estimated from hydraulic head data are used to determine the kinetics of plagioclase and orthoclase feldspar dissolution. Plagioclase surface area measurements were determined using the evolution of the U-series isotope ratios in the groundwater and are compared to published surface area measurements. Calculated rates of dissolution for plagioclase range from 2.4 x 10-12 to 4.6 x 10-16 mol/m2/s and orthoclase from 2.0 x 10-13 to 6.8 x 10-16 mol/m2/s respectively. These feldspar reaction rates, correlate with the degree of mineral-fluid disequilibrium and are similar to the dissolution rates for these mineral measured in other natural CO2-charged groundwater systems.Carbon research at Cambridge is supported by Natural Environment Research Council grant NE/F004699/1, part of the UK CRIUS (Carbon Research Into Underground Storage) consortium and DECC through the ‘£20 million’ competition. Niko Kampman acknowledges financial support from Shell Global Solutions International.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.apgeochem.2015.06.01

Archaeological Geophysical Prospection in Peatland Environments: case studies and suggestions for future practice

Peatland environments, in contrast to ‘dry-land’ sites, preserve organic material, including anthropogenic objects, because they are anaerobic, and are therefore of great importance to archaeology. Peat also preserves macro- and micro- paleoenvironmental evidence and is the primary resource for understanding past climates and ecology. Archaeological sites often lie within or at the base of wet, deep, homogenous peat rendering them invisible to surface observers. As a result, they most often c..

Pleuroparenchymal sarcoidosis - A recognised but rare manifestation of disease

Pleural involvement is rare in sarcoidosis. The presence of a large symptomatic effusion in a patient with sarcoidosis should therefore prompt further investigation for an alternate aetiology. Here we present a case of confirmed pleuro-parenchymal sarcoidosis. We discuss the important differential diagnoses and review the current literature

Management of Septated Malignant Pleural Effusions

Purpose of Review: We review recent studies of patients with septated malignant pleural effusions, to understand what the clinical implications for patients are and what evidence-based methods should be used to manage these effusions. Recent Findings: Fibrinolytics improve effusion size assessed radiologically in patients with a chest drain inserted for septated malignant pleural effusions but this does not translate into an improvement in breathlessness relief or pleurodesis success. Fibrinolytics have also been used in patients with septated effusions associated with indwelling pleural catheters, but dyspnoea relief has not been assessed in this population. Patients with septated effusions or extensive adhesions appear to have a worse prognosis. Summary: Patients with septated malignant pleural effusions have a poor prognosis and do not gain clinical benefit from fibrinolytics via chest drain. The role of fibrinolytics for septated effusions associated with indwelling pleural catheters requires further study