16,952 research outputs found
Multichannel wireway adapter box
Adapter box provides continuous separation of different electrical leads at points where their runs must intersect. Thus, multichannel conduits of standard commercial design may be used in a manner that prevents crossing of wire leads carrying different currents where the runs intersect and change direction
One-way nesting for a primitive equation ocean model
Prognostic numerical models for atmospheric and oceanic circulations require initial fields, boundary conditions, and forcing functions in addition to a consistent set of partial differential equations, including a state relation and equations expressing conservation of mass, momentum, and energy. Depending on the horizontal domain to be modeled, the horizontal boundary conditions are either physically obvious or extremely difficult to specify consistently. If the entire atmosphere is modeled, periodic horizontal boundary conditions are appropriate. On the other hand, the physical horizontal boundaries on the entire ocean are solid walls. Obviously, the normal velocity at a solid wall is zero while the specification of the tangential velocity depends on the mathematical treatment of the horizontal viscous terms. Limitations imposed by computer capacity and cost, as well as research interests, have led to the use of limited area models to study flows in the atmosphere and ocean. The limited area models do not have physical horizontal boundaries, merely numerical ones. Correctly determining these open boundary conditions for limited-area numerical models has both intrigued and frustrated numerical modelers for decades. One common approach is to use the closed or solid wall boundary conditions for a limited-area model. The argument given for this approach is that the boundary conditions affect flow near the walls but that none of these effects are propagated into the interior. Therefore, one chooses a big enough domain that the central region of interest is not corrupted by the boundary flow. Research in progress to model the North Atlantic circulation vividly illustrates the pitfalls of this approach. Two model runs are compared: (1) the southern boundary at 20S between latitudes 0 and 40W is artificially closed; and (2) the same boundary is specified as open with an inward transport of 15 Sv (determined from a global model with the same physics) uniformly spread across the boundary. A comparison of both runs is presented
Reducing Medication Errors Through Workflow Redesign
Lack of medication reconciliation at the point of transitions between skilled nursing facilities/nursing homes (SNF/NHs) and acute care hospitals (ACHs) is a common point of origin for medical errors that cause harm to patients. The goal of this quality improvement initiative was to improve medication reconciliation at the point of transition from the SNF/NH to the ACH which in turn would reduce medication errors, adverse drug events, and medication-induced injury to the vulnerable elderly population. We implemented a workflow redesign process to reconcile the accuracy of residents’ medications at the time of transfer from the SNF/NH to the ACH. After the initiation of a medication reconciliation protocol, 72% (n=13/18) of the medication administration records (MARs) had no medication errors
Cash Flow Trends and Their Fundamental Drivers: A Continuing Look Comprehensive Industry Review (Qtr 4, 2008)
This research report is one of a series that looks at the cash flow performance of Corporate America. Our primary focus is on free cash margin, or free cash flow measured as a percent of revenue. We also look at the drivers or components of free cash margin in an effort to determine factors behind observed changes. In the current study we conduct a comprehensive review of 20 four-digit GICS non-financial industries and their 61 six-digit GICS sub-industries for a series of rolling twelve-month periods from the first quarter of 2000 through the fourth quarter of 2008.
Recession notwithstanding, due to declining capital expenditures and reduced working capital requirements, free cash margin held up reasonably well during the twelve months ended December 2008. The metric declined to 4.12%, down from a high of 5.14% reached in June 2004, and more recently, the 4.93% level reached in December 2007 and 4.44% in September 2008. With free cash margin at 4.12%, corporate America is generating 4.12 cents of free cash flow for every dollar of revenue generated. The number of industries experiencing declining free cash margin increased from our last report. For our sample as a whole, free cash margin last bottomed at 2.43% during the 2001 recession.
We continue to believe that during the current recession, free cash margin will likely decline to levels that are at or below those found in the 2001 recession, suggesting a continuing contraction of free cash flow of 50% or more from current levels. However, a continuing focus on maintaining low working capital levels and reduced capital expenditures may leave companies better off on a cash flow basis than they were in 2001
The identification of gamma ray induced EAS
Some of the penetrating particles in gamma-induced EAS from Cygnus X-3 observed by a single layer of flash-bulbs under 880 g cm/2 concrete, may be punched through photons rather than muons. An analysis of the shielded flash-tube response detected from EAS is presented. The penetration of the electro-magnetic component through 20 cm of Pb is observed at core distances approx. 10 m
Dispersion of microbes from floors when walking in ventilated rooms
The redispersion factor of microbe-carrying particles, which is the ratio of the concentration of floor-derived microbes in room air to those on a floor surface, was determined, as was the percentage of floor-derived microbes in room air. These relationships were shown to vary according to conditions in the room. Equations were derived that allow these relationships to be calculated for a variety of room conditions, including air supply rates, levels of personnel activity, and the effect of gravitational deposition on microbe-carrying particles.<p></p>
The redispersion factor in ventilated rooms, such as cleanrooms and operating rooms, when the floor surface concentration was measured by nutrient agar contact dishes, was found to vary from about 1.5 x 10-4 to 7.4 x 10-6, and the percentage of floor-derived microbes in room air from about 0.004% to 10.5%. In a typical cleanroom, the redispersion factor is likely to be about 1.0 x 10-4, and the percentage of floor-derived microbes, 0.7. In a typical operating room, the redispersion factor is likely to be about 5.2 x 10-6 and the percentage of floor-derived microbes, 2.<p></p>
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Spatial and temporal variablity of nonmethane hydrocarbon mixing ratios and their relation to photochemical lifetime
The relationship between temporal and spatial variability of C2-C8 nonmethane hydrocarbon mixing ratios and their HO lifetimes (τ) is presented for samples collected during the 1993 North Atlantic Regional Experiment (NARE) and from other urban and remote sites. The C2-C4 alkanes, acetylene and benzene typically define a trend of the form slnx=Aτ-b where slnx is the standard deviation of the ln of the mixing ratio. The relationship extended over a wider range of hydrocarbons in winter. The exponent b ranged in value from 0.2±0.023 for winter urban data where C2-C8 hydrocarbons defined a strongly correlated trend, to 0.56±0.15 for C2-C4 hydrocarbons at a coastal site in Nova Scotia during NARE. The trends are significantly different from that given by the Junge relationship [Junge, 1974]. Data from the Azores do not display such a trend and were likely influenced by local emissions. Variance trends are a useful analytical tool for examining the validity of hydrocarbon measurements
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