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71.
The subject matter is the sustainability of naval forces in combat and the intimate relationships between tactics and logistics. The observation is made that it has been a long time since the United States Navy has worried about logistics in combat and that to some extent combat logistics have become ‘somebody else's’ responsibility. It is argued that combat logistics is inescapably the force commander's responsibility and its dimensions are sketched. Necessarily, the amount of data and calculation is extensive if an accurate picture of the combat logistics states of the force are to be maintained and predictions of future states are to be made. It is in the predictions of future states that the interactions between tactics and logistics become most apparent. The data storage and retrieval and computational aspects suggest a microprocessor-based support system. BGLCSS (battle group logistics co-ordinator support system) is a program of combat logistics data, event routines, and algorithms designed to allow the logistics co-ordinator to track and predict force combat logistics states and provide timely and meaningful insight to the force commander.  相似文献   
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The dissolution process and some solution properties of cellulose in mixtures of liquid ammonia (NH3) and ammonium thiocyanate (NH4SCN) are discussed. The mole fraction ratio of NH3, NH4SCN, and H2O which dissolve cellulose were determined. The effect of temperature on several solution properties was also examined. The temperature coefficient d In [n]/dT for the limiting viscosity number [n] has a value of ?1.58 × 10?2 °C?1. This is considered to be rather large but is, in fact, a common occurrence for almost all cellulose derivatives in solution. The values for the Huggins constant K′ showed no systematic trends with temperature. They did, however, suggest the presence of considerable association of the cellulose in solution. Miscibility results of adding the cellulose solutions to organic liquids are also reported.  相似文献   
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We show that a finite-dimensional tame division algebra D over a Henselian field F has a maximal subfield Galois over F if and only if its residue division algebra \(\overline D \) has a maximal subfield Galois over the residue field \(\overline F \).  相似文献   
75.
Widely tunable optical parametric generation in a photonic crystal fiber   总被引:1,自引:0,他引:1  
We report on the observation of widely tunable optical parametric generation in a photonic crystal fiber. The frequency shift of the generated sidebands that arise from modulational instability is strongly dependent on the detuning of the pump from the fiber's zero-dispersion wavelength. We are able to demonstrate experimentally more than 450 nm of sideband tunability as we tune the pump wavelength over 10 nm. Excellent agreement has been found between the experimentally measured and theoretically predicted shifts.  相似文献   
76.
The nucleus 193Pb was populated via the 168Er(30Si, 5n) reaction at a beam energy of 159 MeV and studied with the EUROGAM II spectrometer. Five new dipole ΔI = 1 cascades have been found. The 193Pb dipole bands are discussed in terms of microscopic HF+BCS calculations. The proposed configurations are based on a high-K two-quasiproton excitation coupled to rotation aligned quasineutrons. Parallel to the dipole bands the six superdeformed bands have been discussed in the framework of microscopic mean-field calculations. The bands are interpreted as three pairs of signature partners based on quasineutron excitations. Cross-talk transitions linking two signature partner superdeformed bands have been observed and, for the first time in lead isotopes, a mean B(M1)/B(E2) ratio value of 0.15±0.04 μ N 2 /e2b2 has been extracted.  相似文献   
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Flame-retardant polyester/cotton fabrics are increasing in importance in the apparel and household fabrics market. Phosphorus-nitrogen flame-retardant systems developed for 100% cotton are not necessarily effective for polyester/cotton blends. Bromine effectively imparts flame-retardant properties of polyester resins. It has been theorized that systems containing both bromine and phosphorus should be suitable for polyester/cotton blends. A thermoanalytical study was undertaken to elucidate the effect of bromine in flame-retardant polyester/cotton blend fabrics. Fabrics having various ratios of polyester to cotton were treated with THPOH---NH3, which is particularly effective on 100% cotton, and with THPC-urea-PVBr, which was designed for 50/50 polyester/cotton blends. For comparison, data are also presented on a 50/50 polyester blend fabric treated with THPOH---NH3 and with THPC—urea flame retardants plus tris(2,3-dibromopropyl) phosphate in a two-step application. TG and DSC data were obtained in atmospheres of either nitrogen or air, using a DuPont 990 Thermal Analysis System2. The thermal changes are assigned to decompositions of cotton, polyester, char, and resin finish. A comparison is made of the effects caused by the different flame-retardant finishes. Ol values and FF 3-71 data are reported.  相似文献   
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