Maintaining traceability for transfer standards in the range of 10 Pa to 5 kPa is critical to many calibration laboratories. However, standards with suitable uncertainty that can also be practically implemented in the typical laboratory have not been available. A new pressure standard based on piston-cylinder technology has been developed that provides the measurement uncertainty needed to supp...

Pseudoexfoliation syndrome is a systemic age-related disease in which abnormal extracellular material is produced and accumulates in many ocular tissues. Its ocular manifestations involve all of the structures of the anterior segment as well as conjunctiva and orbital structures. The presence of pseudoexfoliation should alert the physicians to the increased risks associated during and after cat...

We develop an equilibrium business cycle model where nonconvex delivery costs lead producers of final goods to follow generalized (S,s) inventory policies with respect to intermediate goods. When calibrated to match the average inventory-to-sales ratio in postwar U.S. data, our model reproduces two-thirds of the cyclical variability of inventory investment. Moreover, inventory accumulation is s...

In a dynamic storable good market where demand changes over time, we investigate the producer’s strategic incentives to hold inventories in response to the possibility of buyer stockpiling. The literature on storable goods has demonstrated that buyer stockpiling in anticipation of higher future prices harms the producer’s profitability, particularly when the producer cannot commit to future pri...

We develop an equilibrium business cycle model in which the producers of final goods pursue generalized (S,s) inventory policies with respect to intermediate goods, a consequence of nonconvex factor adjustment costs. Calibrating our model to reproduce the average inventory-to-sales ratio in postwar U.S. data, we find that it explains over half of the cyclical variability of inventory investment...

A critical question in planning a response to bioterrorism is how antibiotics and medical supplies should be stockpiled and dispensed. The objective of this work was to evaluate the costs and benefits of alternative strategies for maintaining and dispensing local and regional inventories of antibiotics and medical supplies for responses to anthrax bioterrorism. We modeled the regional and local...

A modern physics facility must synchronize the operation of equipment over a wide area. The primary purpose of the site wide SNS synchronization and timing system is to synchronize the operation of the LINAC, accumulator ring and neutron choppers and to distribute appropriate timing signals to accelerator systems, including the Injector, LINAC, Accumulator Ring and Experimental Facilities. Sign...

An economical analysis of the LPCVD hot wall tubular reactor functioning is presented including equipment amortization, clean room location, supplies, maintenance, labor, gas and energy consumption. From a technical point of view, CVDl model is used to characterise the phenomena involved during polysilicon deposition, linking growth rate distribution to operating conditions. An optimization is ...

OBJECTIVE In 2000, a referral hospital in the Gambia accepted a donation of oxygen concentrators to help maintain oxygen supplies. The concentrators broke down and were put into storage. A case study was done to find the reasons for the problem and to draw lessons to help improve both oxygen supplies and the success of future equipment donations. METHODS A technical assessment of the concentr...