Wedge disclination in the field theory of elastoplasticity

In this paper we study the wedge disclination within the elastoplastic defect theory. Using the stress function method we found exact analytical solutions for all characteristic fields of a straight wedge disclination in a cylinder. The elastic stress, elastic strain, elastic bend-twist, displacement and rotation have no singularities at the disclination line. We found a modified stress function for the wedge disclination.Comment: 11 pages, 3 figure

Risky Business: Intra-Firm Trade with Foreign Commercial Risk and Asymmetric Insurance

A partial equilibrium model is used to examine the international production allocation of a two-plant risk averse multinational firm which is confronted with uncertainty with respect to foreign sales. The firm has price-discriminating monopoly power in both markets and uses specific factors in both plants, producing an identical good. We focus on the question how unequal insurance facilities in the firm’s home and host market influence the firm’s international production decision and its level of intra-firm trade.multinationals; uncertainty; export insurance; intra-firm trade

Extensional tectonics during the igneous emplacement of the mafic-ultramafic rocks of the Barberton greenstone belt

The simatic rocks (Onverwacht Group) of the Barberton greenstone belt are part of the Jamestown ophiolite complex. This ophiolite, together with its thick sedimentary cover occupies a complex thrust belt. Field studies have identified two types of early faults which are entirely confined to the simatic rocks and are deformed by the later thrusts and associated folds. The first type of fault (F1a) is regional and always occurs in the simatic rocks along and parallel to the lower contacts of the ophiolite-related cherts (Middle Marker and equivalent layers). These fault zones have previously been referred to both as flaser-banded gneisses and as weathering horizons. In general the zones range between 1-30m in thickness. Displacements along these zones are difficult to estimate, but may be in the order of 1-100 km. The structures indicate that the faults formed close to horizontal, during extensional shear and were therefore low angle normal faults. F1a zones overlap in age with the formation of the ophiolite complex. The second type of faults (F1b) are vertical brittle-ductile shear zones, which crosscut the complex at variable angles and cannot always be traced from plutonic to overlying extrusive (pillowed) simatic rocks. F1b zones are also apparently of penecontemporaneous origin with the intrusive-extrusive igneous processs. F1b zones may either represent transform fault-type activity or represent root zones (steepened extensions) of F1a zones. Both fault types indicate extensive deformation in the rocks of the greenstone belt prior to compressional overthrust tectonics

Tax uniformity: A commitment device for restraining opportunistic behaviour.

We investigate whether and to what extent uniform and differentiated tax systems diverge in their propensity to create distortionary opportunistic behavoiur. The set-up in which we carry out our analysis features polluting firms that are confronted with existence a Pigovian emission tax. Firms can invest in pollution abatement. We first show that the existence of emmission taxes, although optimally chosen, create strategic incentives for firms to distort their abatement investment. Second, we find that a system of differentiated emission taxes has a greater propensity to foster strategic distortions in abatement investment than a uniform emission tax regime.Uniform tax, Differentiated taxes, Emission tax, Short-run policy commitment, Pollution-abating investment, Strategic investment.

Short-run policy commitment when investment timing is endogenous: "More harm than good?"

We introduce endogenous leadership in a game between government and firms, in which the government has short-run commitment power only and firms choose when to invest. We show that firms that delay investment in the absence of government intervention have an incentive to invest early and strategically under policy activism. Then, even though a policy scheme succeeds in correcting an existing distortion targeted by the government, it can create a new and potentially more harmful one. We investigate when the government may do better by adhering to laissez-faire than by engaging in active policy intervention.Short-run government commitment, Microeconomic policy,Endogenous policy leadership, Investment timing,Uncertainty, Laissez faire

Oligopsonistic Cats and Dogs

We study the strategic investment behaviour of oligopsonistic rivals in the labour market. Under wage competition, firms play "puppy dog" with productivityaugmenting investment and "fat cat" with supply-enhancing investment. Under employment competition, investing strategically always involves playing "top dog".Oligopsony,Strategic behaviour,Productivity-augmenting investment

A case of sectoral export promotion: Export insurance subsidies in Belgium.

Belgium; export promotion; Insurance; Subsidies;

Strategic Investment and the Gains from Trade

This paper examines how trade liberalisation affects innovation, profits and welfare when firms are engaging in strategic R&D investment. We show that there are multiple equilibria including an autarky equilibrium for a range of high but non-prohibitive trade costs. At lower trade costs, only the trading equilibrium survives. Welfare is U-shaped in the trade costs, so a small fall in trade costs can be welfare reducing. However we find a threshold level of the effectiveness of investment above which trade is always welfare superior to autarkyReciprocal Markets, Strategic R&D Investment, Trade Costs, Trade Liberalisation, Effectiveness of R&D.