19,286 research outputs found
The effect of growth hormone on the growth of the tibia/fibula complex and femurs of hypophysectomized rats after unilateral limb denervation
Thesis (M.Sc.D.)--Boston University School of Graduate Dentistry, 1972 (Orthodontics)Bibliography included
Division and the Giambelli Identity
Given two polynomials f(x) and g(x), we extend the formula expressing the
remainder in terms of the roots of these two polynomials to the case where f(x)
is a Laurent polynomial. This allows us to give new expressions of a Schur
function, which generalize the Giambelli identity.Comment: 9 pages, 1 figur
Operational cost drivers
To be economically viable, the operations cost of launch vehicles must be reduced by an order of magnitude as compared to the Space Transportation System (STS). A summary of propulsion-related operations cost drivers derived from a two-year study of Shuttle ground operations is presented. Examples are given of the inordinate time and cost of launch operations caused by propulsion systems designs that did not adequately consider impacts on prelaunching processing. Typical of these cost drivers are those caused by central hydraulic systems, storable propellants, gimballed engines, multiple propellants, He and N2 systems and purges, hard starts, high maintenance turbopumps, accessibility problems, and most significantly, the use of multiple, nonintegrated RCS, OMS, and main propulsion systems. Recovery and refurbishment of SRBs have resulted in expensive crash and salvage operations. Vehicle system designers are encouraged to be acutely aware of these cost drivers and to incorporate solutions (beginning with the design concepts) to avoid business as usual and costs as usual
CIRCA 2000 operations criteria
The current Shuttle Program was used as a working model and certified data source in the identification of Space Transportation System (STS) operational cost drivers. Changes to flight hardware, processing methodologies, and identification of automation applications that would reduce costs were derived by reference to that data. The CIRCA 2000 Criteria were developed using these critical analyses of the on-going Shuttle Program. Several innovative suggestions are reviewed
High effectiveness contour matching contact heat exchanger
There is a need in the art for a heat exchanger design having a flexible core providing contour matching capabilities, which compensates for manufacturing tolerance and distortion buildups, and which accordingly furnishes a relatively uniform thermal contact conductance between the core and external heat sources under essentially all operating conditions. The core of the heat exchanger comprises a top plate and a bottom plate, each having alternate rows of pins attached. Each of the pins fits into corresponding tight-fitting recesses in the opposite plate
Sensitivity of LDEF foil analyses using ultra-low background germanium vs. large NaI(Tl) multidimensional spectrometers
Cobalt foils and stainless steel samples were analyzed for induced Co-60 activity with both an ultra-low background germanium gamma-ray spectrometer and with a large NaI(Tl) multidimensional spectrometer, both of which use electronic anticoincidence shielding to reduce background counts resulting from cosmic rays. Aluminum samples were analyzed for Na-22. The results, in addition to the relative sensitivities and precisions afforded by the two methods, are presented
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