Postcards from the Edge: A Review of the Business and Environment Literature

Environmental issues, while of growing interest, have been outside the main focus of business scholarship. This position on the periphery may have been a good thing. It allowed scholars of business and the environment to consider unusual theories and evaluate overlooked phenomenon. In doing so, they created a body of research that provides new insights on two topics of mainstream interest -- the sources of competitive advantage and the origin and function of self-regulatory institutions.competitive advantage;business and environment;environmental issues

Postcards from the Edge: A Review of the Business and Environment Literature

Environmental issues, while of growing interest, have been outside the main focus of business scholarship. This position on the periphery may have been a good thing. It allowed scholars of business and the environment to consider unusual theories and evaluate overlooked phenomenon. In doing so, they created a body of research that provides new insights on two topics of mainstream interest -- the sources of competitive advantage and the origin and function of self-regulatory institutions

Ink Drying in Inkjet Printers

The first problem put to the Study Group for Maths in Industry by Domino UK Ltd concerns ink drying and blocking nozzles in a printer. The goals were as follows: 1. To propose mechanisms for the growth of a plug of dried ink in the open end of a Drop-on-Demand drop generator, 2. To suggest cures to this problem, 3. To consider why oscillating the meniscus appears to alleviate the problem

The Strategic Determinants of Tardy Entry: Is Timeliness Next to Godliness?

Previous research has considered extensively the causes and effects of market entry order and timing. It has neglected, however, the timeliness of such entry — the degree to which a firm delivered a new product on the date it had set for its release. In this article, we begin to fill the need for such research by evaluating some strategic explanations for why a firm might miss a scheduled entry date. We then test whether such “tardy entry” influences sales performance in the new market

Mobile radio propagation prediction using ray tracing methods

The basic problem is to solve the two-dimensional scalar Helmholtz equation for a point source (the antenna) situated in the vicinity of an array of scatterers (such as the houses and any other relevant objects in 1 square km of urban environment). The wavelength is a few centimeters and the houses a few metres across, so there are three disparate length scales in the problem. The question posed by BT concerned ray counting on the assumptions that: (i) rays were subject to a reflection coefficient of about 0.5 when bouncing off a house wall and (ii) that diffraction at corners reduced their energy by 90%. The quantity of particular interest was the number of rays that need to be accounted for at any particular point in order for those neglected to only contribute 10% of the field at that point; a secondary question concerned the use of rays to predict regions where the field was less than 1% of that in the region directly illuminated by the antenna. The progress made in answering these two questions is described in the next two sections and possibly useful representations of the solution of the Helmholtz equations in terms other than rays are given in the final section

Generalized plane-fronted gravitational waves in any dimension

We study the gravitational waves in spacetimes of arbitrary dimension. They generalize the pp-waves and the Kundt waves, obtained earlier in four dimensions. Explicit solutions of the Einstein and Einstein-Maxwell equations are derived for an arbitrary cosmological constant.Comment: Revtex, 18 pages, no figure

New solutions in 3D gravity

We study gravitational theory in 1+2 spacetime dimensions which is determined by the Lagrangian constructed as a sum of the Einstein-Hilbert term plus the two (translational and rotational) gravitational Chern-Simons terms. When the corresponding coupling constants vanish, we are left with the purely Einstein theory of gravity. We obtain new exact solutions for the gravitational field equations with the nontrivial material sources. Special attention is paid to plane-fronted gravitational waves (in case of the Maxwell field source) and to the circularly symmetric as well as the anisotropic cosmological solutions which arise for the ideal fluid matter source.Comment: Revtex, 21 pages, no figure

Electron localization : band-by-band decomposition, and application to oxides

Using a plane wave pseudopotential approach to density functional theory we investigate the electron localization length in various oxides. For this purpose, we first set up a theory of the band-by-band decomposition of this quantity, more complex than the decomposition of the spontaneous polarization (a related concept), because of the interband coupling. We show its interpretation in terms of Wannier functions and clarify the effect of the pseudopotential approximation. We treat the case of different oxides: BaO, $\alpha$-PbO, BaTiO$_3$ and PbTiO$_3$. We also investigate the variation of the localization tensor during the ferroelectric phase transitions of BaTiO$_3$ as well as its relationship with the Born effective charges

Tilt and phantom cosmology

We show that in tilting perfect fluid cosmological models with an ultra-radiative equation of state, generically the tilt becomes extreme at late times and, as the tilt instability sets in, observers moving with the tilting fluid will experience singular behaviour in which infinite expansion is reached within a finite proper time, similar to that of phantom cosmology (but without the need for exotic forms of matter).Comment: 9 pages, v2: more discussion, added reference