Price vs. revenue stabilization through a buffer stock: Which is more financially feasible for LDCs?
Abstract Optimal control theory is used to analyze the implications of the adoption of price and LDC export revenue stabilization objectives by an international buffer stock for cocoa. The results obtained for the period 1956–76 suggest that the stabilization of either price or revenue at systematic trend would reduce the instability of both variables from that during the sample period. Although the stabilization of revenues at systematic trend decreases their average level, the stabilization of price has the opposite effect. Because of this, it may be financially feasible for the LDCs to provide the necessary resources for a price-stabilizing buffer stock.
INSTABILITY IN WORLD GRAIN MARKETS
The paper discusses the nature of international price variability for wheat and coarse grains. In particular, it explores the relationship between variability in national grain markets and international trade. Empirical evidence is presented on the degree to which short-run fluctuations in domestic grain production are transmitted to the world market by major countries or country aggregates, and on their absorption of international market variability. The impact of possible structural or policy changes upon future international price variability is explored. It is argued that multilateral action to promote greater international stability should focus on the modification of domestic storage policies to reduce the transmission of short-run domestic fluctuations in supply or demand to world markets.
Effect of stress conditions on collapse deformation behavior of a rockfill material
A set of saturated and dry-saturated large-scale triaxial tests were conducted in order to explore the effects of stress conditions on the saturation-induced collapse deformation behavior of a rockfill material. Specimens were tested in different confining pressures and for dry-saturated tests the specimens were submerged in various shear stress levels. The results indicate that in all of the dry-saturated tests a sudden reduction in the volume of the specimens was observed during the submerging process. The ratio of the minimum axial strength of a submerged specimen (at the end of the saturation process) to the shear strength of the specimen before saturation is defined as the coefficient of stress recovery, Csr. Results of the dry-saturated tests showed that this ratio increases as the confining pressure increases and decreases by increasing the shear stress level. According to the results of dry-saturated tests the values of internal friction angle reduction caused by saturation (Δϕc), the ratio of the elasticity modulus of the material after saturation to its elasticity modulus in dry condition, i.e., Ewet/Edry, and also the saturation induced sudden volumetric strain (εvc) decrease as the confining pressure increases. However the shear stress level does not have any meaningful effect on the variation of Dfc, Ewet/Edry and (εvc).