Risk analysis of a construction cost estimate

A risk analysis of a construction cost estimate for a large hydroelectric project is discussed. The purpose of the study was to provide an independent check on the reliability of the estimate and the adequacy of the contingency allowance. The paper describes the basecost estimate, the risk analysis approach, the sources of risk considered, the details of the risk analysis method and the implementation of the risk analysis. The relationship between this form of risk analysis and the cost estimating process is discussed in some detail. It is concluded that a combined approach may be possible and that the benefits could be substantial.     

Performance of small-radius thin-wall drift tubes in an SSCradiation environment at the MIT Research Reactor

Drift tubes of 1.9-mm radius and 25-μ wall thickness were exposed to neutrons and associated gamma radiation from uranium fission at the MIT Research Reactor. In 45 hours of irradiation, the drift tubes received a neutron fluence with energy greater than 0.5 MeV of 1.1×10¹³ cm^-2 And accumulated a charge per wire length of 0.08 coul cm^-1, about that expected for three years of operation at the SSC for a lead scintillator calorimeter at a 1-m radius and for drift tubes at a distance of several tens of centimeters from the beam axis. Measurement of the pulse height, pulse shape, counting rates, andcurrents showed no degradation in drift tube performance. Fast (few nanosecond rise time), sharp (20-ns width) pulses were observed at counting rates of 5 MHz using CF₄ as the drift gas     

Bacteriology of tonsil and adenoid and sampling techniques of adenoidal bacteriology

Twenty-six laboratories including 22 Blood Transfusion Centres in England, Scotland, Wales and Northern Ireland participated in a collaborative study to assess the suitability of proposed working standards for hepatitis B surface antigens (HBsAg) for use in the UK Blood Transfusion Service. Data from 88 assays indicated that all laboratories could detect HBsAg in the proposed working standard at a concentration of 0.5 IU/ml. Samples containing HBsAg at a concentration of 0.125 IU/ml were scored positive in 80% of assays and it was concluded that this would be a suitable concentration for inclusion in a monitor sample which would indicate whether the sensitivity of an assay system in routine use is varying over a period of time. The use of a batch of 'provisional' working standard tested under field conditions over a period of 4 months has been monitored. HBsAg was not detected in only 2 out of 6,523 assays.     

Intraarterial papaverine as an adjunct to transluminal angioplasty for vasospasm induced by subarachnoid hemorrhage

Basilar artery vasospasm refractory to medical therapy was confirmed by clinical deterioration and angiography in a 47-year-old man; successful passage of a nondetachable balloon system and angioplasty were facilitated by intraarterial papaverine.