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21.
The telecommunications arena is currently undergoing a period of metamorphosis in which the traditional roles of organisations and the services they offer are likely to experience significant transformations. This transitional regime will probably last through to the turn of the century and presents a considerable challenge to our creativity as we attempt to develop an adequate set of tools for advising on corporate policy.This paper maps out the development path of a dynamic strategic model beginning with a discussion of alternative viewpoints of the future and our conceptual framework. We then describe the computer package itself which includes a brief overview of a recently developed control module which will track a set of corporate objectives. The last three sections are all concerned with various aspects of the implementation of both the computer package and the strategic plans themselves.  相似文献   
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Measurements of whistler-mode electron-cyclotron emission made in the Phaedrus-B tandem-mirror end cell are described. The receiving horn was located on the axis of the machine just outboard of the end cell. Under normal conditions, the signal had a component which was identified as blackbody emission, and an electron temperature was obtained which was in good agreement with electron end loss-energy-analyzer data. In addition, the signal contained short bursts of unknown origin. Significant heating of the electrons due to end-cell ion-cyclotron frequency range (ICRF) was seen. Comparison of end loss and Thomson scattering data shows that emission from hotter edge electrons is responsible for a large part of the total signal  相似文献   
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We have developed synthesis routes for the introduction of short and long dialkylsulfides onto the primary side of alpha-, beta-, and gamma-cyclodextrins. Monolayers of these cyclodextrin adsorbates were characterized by electrochemistry, wettability studies, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (TOF-SIMS), and atomic force microscopy (AFM). The differences in thickness and polarity of the outerface of the monolayers were measured by electro-chemistry and wettability studies. On average about 70% of the sulfide moieties were used for binding to the gold, as measured by XPS. Tof-SIMS measurements showed that the cyclodextrin adsorbates adsorb without any bond breakage. AFM measurements revealed for beta-cyclodextrin monolayers a quasi-hexagonal lattice with a lattice constant of 20.6 A, which matches the geometrical size of the adsorbate. The alpha-cyclodextrin and gamma-cyclodextrin monolayers are less ordered. Interactions of the anionic guests 1-anilinonaphthalene-8-sulfonic acid (1,8-ANS) and 2-(p-toluidinyl)naphthalene-6-sulfonic acid (2,6-TNS) and the highly ordered monolayers of heptapodant beta-cyclodextrin adsorbates were studied by surface plasmon resonance (SPR) and electrochemical impedance spectroscopy. The SPR measurements clearly showed interactions between a beta-cyclodextrin monolayer and 1,8-ANS. Electrochemical impedance spectroscopy measurements gave high responses even at low guest concentrations (< or = 5 microM). The association constant for the binding of 1,8-ANS (K = 289,000 +/- 13,000M-1) is considerably higher than the corresponding value in solution. (Partial) methylation of the secondary side of the beta-cyclodextrin strongly decreases the binding.  相似文献   
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The advantages of performing Langevin dynamics in extended systems are discussed. A simple Langevin dynamics scheme for producing the canonical ensemble is reviewed, and is then extended to the Hoover ensemble. We show that the resulting equations of motion generate the isobaric-isothermal ensemble. The Parrinello-Rahman ensemble is then discussed and we show that despite the presence of intrinsic probability gradients in this system, a Langevin dynamics approach samples the extended phase space in the correct fashion. The implementation of these methods in the ab initio plane wave density functional theory code CASTEP [M. D. Segall, P. L. D. Lindan, M. J. Probert, C. J. Pickard, P. J. Hasnip, S. J. Clarke, and M. C. Payne, J. Phys.: Condens. Matter 14, 2717 (2003)] is demonstrated.  相似文献   
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Some new phosphorus(III) derivatives Ar(2)PX (X = Br, Cl, F or H), ArPX(2) (X = Br or Cl), Ar(3)P and Ar(t)BuPCl, with the 2,5-bis(trifluoromethyl)phenyl (Ar) substituent on phosphorus, have been prepared, and characterised by (31)P and (19)F NMR solution-state spectroscopy. The complexing ability of Ar(2)PX, Ar(3)P and Ar(t)BuPCl towards the dimeric platinum(II) complexes [PtY(μ-Y)(PEt(3))](2) (Y = Cl or Br, the latter for X = Br only) has also been investigated. Single-crystal X-ray diffraction studies at low temperature have been carried out for Ar(3)P, Ar(2)PCl and the hydrolysis or oxidation products Ar(2)P(H)OH and Ar(2)P(O)OH. The structures of Ar(3)P and Ar(2)PCl are particularly interesting as in each compound the geometry around P is approximately octahedral. In Ar(3)P there are three short contacts to fluorine as well as the three bonded C atoms for both of the independent molecules in the unit cell. For Ar(2)PCl there are two short P-F contacts, and the octahedron is completed by a weak P-P interaction to a neighbouring molecule. In both instances the lone pair on the P(III) centre appears to be stereochemically inactive, and does not play a significant role in the structure.  相似文献   
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