69,088 research outputs found
Enteral feeding pumps: efficacy, safety, and patient acceptability.
Enteral feeding is a long established practice across pediatric and adult populations, to enhance nutritional intake and prevent malnutrition. Despite recognition of the importance of nutrition within the modern health agenda, evaluation of the efficacy of how such feeds are delivered is more limited. The accuracy, safety, and consistency with which enteral feed pump systems dispense nutritional formulae are important determinants of their use and acceptability. Enteral feed pump safety has received increased interest in recent years as enteral pumps are used across hospital and home settings. Four areas of enteral feed pump safety have emerged: the consistent and accurate delivery of formula; the minimization of errors associated with tube misconnection; the impact of continuous feed delivery itself (via an enteral feed pump); and the chemical composition of the casing used in enteral feed pump manufacture. The daily use of pumps in delivery of enteral feeds in a home setting predominantly falls to the hands of parents and caregivers. Their understanding of the use and function of their pump is necessary to ensure appropriate, safe, and accurate delivery of enteral nutrition; their experience with this is important in informing clinicians and manufacturers of the emerging needs and requirements of this diverse patient population. The review highlights current practice and areas of concern and establishes our current knowledge in this field
Preduals of semigroup algebras
For a locally compact group G, the measure convolution algebra M(G) carries a natural coproduct. In previous work, we showed that the canonical predual C 0(G) of M(G) is the unique predual which makes both the product and the coproduct on M(G) weak*-continuous. Given a discrete semigroup S, the convolution algebra ℓ 1(S) also carries a coproduct. In this paper we examine preduals for ℓ 1(S) making both the product and the coproduct weak*-continuous. Under certain conditions on S, we show that ℓ 1(S) has a unique such predual. Such S include the free semigroup on finitely many generators. In general, however, this need not be the case even for quite simple semigroups and we construct uncountably many such preduals on ℓ 1(S) when S is either ℤ+×ℤ or (ℕ,⋅)
Measured and predicted shock shapes and aerodynamic coefficients for blunted cones at incidence in helium at Mach 20.3
Experimental values of shock shapes (alpha = 0 degrees and 10 degrees) and static aerodynamic coefficients (alpha = -4 degrees to 12 degrees) for sharp and spherically blunted cones having cone half-angles of 30, 45, 60, and 70 degrees and nose bluntness ratios of 0, 0.25, and 0.50 are presented. Shock shapes were also measured at 0 degree angle of attack by using a flat-faced cylinder (90 degree cone) and a hemispherically blunted cylinder (sphere). All tests were conducted in helium (gamma = 5/3) at a free-stream Mach number of 20.3 and a unit free-stream Reynolds number of 22,400,000 per meter. Comparisons between measured values and predicted values were made by using several numerical and simple engineering methods
A simplified PERT system
Modified PERT technique processes the input data and arranges it in familiar graphic form in a booklet which is issued at periodic intervals. The tabulated data provides readily available information to management personnel concerned with monitoring the progress of a program
Effects of the roller feed ratio on wrinkling failure in conventional spinning of a cylindrical cup
In this study, wrinkling failure in conventional spinning of a cylindrical cup has been investigated by using both finite element (FE) analysis and experimental methods. FE simulation models of a spinning experiment have been developed using the explicit finite element solution method provided by the software Abaqus. The severity of wrinkles is quantified by calculating the standard deviation of the radial coordinates of element nodes on the edge of the workpiece obtained from the FE models. The results show that the severity of wrinkles tends to increase when increasing the roller feed ratio. A forming limit study for wrinkling has been carried out and shows that there is a feed ratio limit beyond which the wrinkling failure will take place. Provided that the feed ratio is kept below this limit, the wrinkling failure can be prevented. It is believed that high compressive tangential stresses in the local forming zone are the causes of the wrinkling failure. Furthermore, the computational performance of the solid and shell elements in simulating the spinning process are examined and the tool forces obtained from wrinkling and wrinkle-free models are compared. Finally, the effects of the feed ratio on variations of the wall thickness of the spun cylindrical cup are investigated. </jats:p
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