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201.
One of the functions of government is to invest tax dollars in programs, projects, and properties that will result in greater
public benefit than would have resulted from leaving the tax dollars in the private sector or using them to pay off the public
debt. This paper describes the use of Net Present Value(npv) as an approach to analyze and select investment opportunities for government money in public research, development, and demonstration
(RD&D) programs and to evaluate potential private sector participation in the programs. This approach is then applied to a
specific biomass-to-ethanol opportunity in California. 相似文献
202.
203.
Jeffrey P. Emerson Daniel A. Wright Robert A. Fisher Norman E. Phillips 《Czechoslovak Journal of Physics》1996,46(3):1209-1210
The specific heat and magnetic susceptibility of a sample of YBa2Cu3O7?δ (YBCO) was measured for 0≤δ≤0.85, 0.8≤T≤120K, and H=0, 3, 5, 7, 9T. The data show the existence of both S=1/2 and S=2 paramagnetic centers, consistent with EPR results. The δ dependences of their concentrations and of other parameters are reported. 相似文献
204.
205.
Vassilios Fessatidis Norman J.M. Horing 《Physica E: Low-dimensional Systems and Nanostructures》2005,27(4):487-494
We examine the collective mode spectrum for a double quantum-wire system embedded in semi-infinite polar medium, taking account of the role of optical phonons in interaction with the double quantum-wire plasmons and bulk/surface plasmons. The collective mode frequencies are exhibited as functions of qx (wavenumber parallel to the wires) and as functions of z0 (distance of first wire from the interface). We also find that the region of drift instability of the collective modes is split into two disjoint regions of instability by the optical phonons, with a region of stability between them. 相似文献
206.
207.
A methodology to create robust job rotation schedules 总被引:1,自引:0,他引:1
This research proposes a methodology for developing robust job rotation schedules to reduce the likelihood of low back injury
due to lifting. We consider settings that have uncertain task demands and different worker profiles in order to simulate real
settings. We begin by considering deterministic versions of the problem and solve these using mathematical programming. Because
mathematical programming cannot be readily applied to stochastic versions of the problem, heuristic solution methods are developed.
The effectiveness of these methods is demonstrated by comparing the results with provably optimal solutions from the deterministic
problems and with an enumerative approach that is applied to the stochastic version of the problem. Across the test problems,
the proposed heuristics are effective at finding good job rotation solutions. The proposed methods could also be applied to
solve other job rotation objectives such as maximizing productivity and reducing exposure to other work environmental factors
such as excessive noise. 相似文献
208.
Journal of Experimental and Theoretical Physics - Langmuir waves and particle-particle collisions in an equilibrium two-component plasma consisting of nondegenerate electrons and singly charged... 相似文献
209.
Ksenija Babić-Samardžija Norman Hackerman 《Journal of Solid State Electrochemistry》2005,9(7):483-497
The effect of a 1H-1,2,3-triazole, 1,2,3-benzotriazole and a number of substituted benzotriazoles, namely 1-hydroxybenzotriazole, 1H-benzotriazole-1-methanol and N-(1H-benzotriazol-1-ylmethyl)-formamide, have been investigated with respect to the corrosion of iron in 1 mol/l HCl and 1 mol/l HClO4. The Tafel extrapolation method, linear polarization resistance and electrochemical impedance spectroscopy illustrate the inhibiting effect of all of these compounds in both acids. They are better inhibitors in 1 mol/l HCl than in 1 mol/l HClO4. The changes of charge transfer resistance are also indicative for adsorption and inhibition of all of these compounds. This effect increases with time up to 16 h. An equivalent circuit is suggested as a model for the impedance. The adsorption of triazole-type of compounds in both acids follows a Langmuir isotherm. Molecular modeling was used to gain some insight, about structural and electronic effects in relation to the inhibiting efficiencies. 相似文献
210.
Norman Gray. 《Mathematics of Computation》2002,71(237):311-318
In a series of papers, B. C. Carlson produced tables of elliptic integrals, evaluating them in terms of easily computed symmetrical functions, using a group of multivariate recurrence relations. These relations are, however, cumbersome to use by hand and, in the absence of a specific reductive algorithm, difficult to use with computer algebra. This paper presents such an algorithm, guaranteed to reduce a general elliptic integral to a set of fundamental ones.