Devolving command decisions in complex operations

In contemporary military endeavours, Command and Control (C2) arrangements generally aim to ensure an appropriate regulation of command-decision autonomy such that decision makers are able to act in a way that is consistent with the overall set of commanders’ intents and according to the nature of the unfolding situation. This can be a challenge, especially in situations with increasing degrees of uncertainty, ambiguity and complexity, also where individual commanders are faced with conflicting objectives. Increasingly, it seems that command decisions are being taken under conditions of internal command contention; for example, when the likely successful outcome of a tactical mission can often be at odds with the overall strategic and political aims of the campaign. The work in the paper builds on our previous research in decision making under uncertainty and conflicting objectives, where we analysed the responses of military commanders in decision experiments. We demonstrated how multi-attribute utility theory could be used to represent and understand the effects of uncertainty and conflicting objectives on a particular commander's choices. In this paper, we further develop and generalize the theory to show that the geometrical forms of expected utilities, which arise from the assumption of commander rationality, are qualitatively stable in a wide range of scenarios. This opens out into further analysis linking to Catastrophe Theory as it relates to C2 regulatory frameworks for devolving command decision freedoms. We demonstrate how an appreciation of this geometry can aid understanding of the relationship between socially complex operational environments and the prevailing C2, which can also inform selection and training of personnel, to address issues of devolving command decision-rights, as appropriate for the endeavour as a whole. The theory presented in the paper, therefore, provides a means to explore and gain insight into different approaches to regulation of C2 decision making aimed ultimately at achieving C2 agility, or at least at a conceptual language to allow its formal representation. C2 regulatory agents are discussed in terms of detailed functions for moderating command decision making, as appropriate for the degrees of uncertainty and goal contention being faced. The work also begins to address implications of any lack of experience and any differences in personality-type of the individual commanders with respect to risk-taking, open-mindedness and creativity.     

Syntheses and structures of isoindoline complexes of Zn(II) and Cu(II): an unexpected trinuclear Zn(II) complex

Deprotonation of the tridentate isoindoline ligand 1,3-bis[2-(4-methylpyridyl)imino]-isoindoline, 4'-MeLH, and reaction with hydrated zinc(II) perchlorate produces an unexpected trinuclear Zn(II) complex, [Zn(3)(4'-MeL)(4)](ClO(4))(2).5H(2)O (1), whereas reaction with hydrated copper(II) perchlorate in methanol produces the expected mononuclear product, [Cu(4'-MeL)(H(2)O)(2)]ClO(4) (2). X-ray diffraction shows that the trinuclear Zn(II) complex (1) contains a linear zinc backbone, and the arrangement of ligands about the outer chiral zinc(II) atoms is helical. The two terminal zinc ions exhibit approximate C(2) site symmetry, with tetrahedral coordination by two pyrrole and two pyridyl nitrogen atoms of the potentially tridentate isoindoline ligands. The central zinc ion exhibits approximate tetrahedral symmetry, with coordination by four pyridyl nitrogen atoms of four different isoindoline ligands. Pyridyl-pyrrole intramolecular pi-stacking interactions contribute to the stability of the trinuclear cation. The structure of the mononuclear copper(II) complex cation in 2 is best described as a distorted trigonal bipyramid. The isoindoline anion binds Cu(II) in both axial positions and one of the equatorial positions; water molecules occupy the other two equatorial positions.     

Electrochemical synthesis and study of polydiphenylamine

The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent conducting polymer film at the electrode. Conductivity measurements on pressed pellets of this polymer give a room temperature conductivity of 10 S cm⁻¹. The polymer can be cycled between 25 and 200°C without deterioration in the conductivity. Preliminary SEM/EDS studies suggest that there is one BF⁻₄ counter ion for every four monomer units in the oxidised polymer film.     

Effect of Particle Size on the Photocatalytic Activity of Nanoparticulate Zinc Oxide

In this study, a three-stage process consisting of mechanical milling, heat treatment, and washing has been used to manufacture nanoparticulate ZnO powders with a controlled particle size and minimal agglomeration. By varying the temperature of the post-milling heat treatment, it was possible to control the average particle size over the range of 28–57 nm. The photocatalytic activity of these powders was characterized by measuring the hydroxyl radical concentration as a function of irradiation time using the spin-trapping technique with electron paramagnetic resonance spectroscopy. It was found that there exists an optimum particle size of approximately 33 nm for which the photocatalytic activity is maximized. The existence of this optimal particle size is attributable to an increase in the charge carrier recombination rate, which counteracts the increased activity arising from the higher specific surface area for a sufficiently small particle size.     

A comparative evaluation of the photocatalytic and optical properties of nanoparticulate ZnO synthesised by mechanochemical processing

In this study, mechanochemical processing has been used to manufacture a nanoparticulate powder of ZnO with a controlled particle size and minimal hard agglomeration. The suitability of this ZnO powder for use as either a photocatalyst or an optically transparent UV-filter was evaluated by comparing its optical and photocatalytic properties with those of three commercially available powders that were synthesised by chemical precipitation and flame pyrolysis. The ZnO powder synthesised by mechanochemical processing was found to exhibit high optical transparency and low photocatalytic activity per unit of surface area, which indicates that it is suitable for use in optically transparent UV-filters.

     

`Spiking' radiation in the Columbia free electron laser

A report is presented on the observation of spikes of high-intensity radiation emitted from a 2-mm wavelength Raman free electron laser oscillator. The spikes are correlated with a well-developed sideband spectrum, including several sideband harmonics, together with the carrier. A pulse width ~150 ps is obtained from analysis of data obtained with a two-slit Young's experiment. An even shorter pulse width results from a numerical model. Using an elementary model of the spike, it is estimated that the peak spike pulse power is ~100 MW     

Nonlinear spectral signatures and spatiotemporal behavior of stimulated Raman scattering from single laser speckles

Simulations are reported of the Thomson scatter spectrum of electrostatic waves (ESWs) excited in single laser hot spots by backward stimulated Raman scattering (BSRS). Under conditions similar those in the recent experiments of Kline et al. [Phys. Rev. Lett. 94, 175003 (2005)], a spectral streak, resulting from the trapping-induced frequency shift of the ESW, is found for high wave-number ESWs, similar to the observations. This shift and parametric frequency matching lead to isolated BSRS pulses. Modes with acoustic dispersion, resulting from the trapping-modified electron velocity distribution, can enhance the frequency range of the streak.