On estimation in weibull distributions with random scale parameters

Work by the present authors on life distributions derived from stochastic hazard functions [4] is related to certain articles that have appeared in this journal. This relationship is illustrated. The emphasis of this article is upon problems of parameter estimation.     

Book reviews

America's Secret Power: the CIA in a Democratic Society. By Loch K. Johnson. Oxford University Press, New York (1989), ISBN 0–19–505490–3, $24.95

The Bundeswehr and Western Security. Edited by Stephen F. Szabo. Houndmills, Basingstoke, and Macmillan, London (1990), ISBN 0–333–49880–1, £45.00

Symbolic Defense: the Cultural Significance of the Strategic Defense Initiative. By Edward Tabor Linenthal. University of Illinois Press, Chicago, IL (1989), ISBN 0–252–01619‐X, $19.95

Rethinking European Security. Edited by Furio Cerutti and Rodolfo Ragionieri. Crane Russak, New York (1990), £29.00

Alternative Conventional Defense Postures in the European Theater, Vol. 1: The Military Balance and Domestic Constraints. Edited by Hans Günter Brauch and Robert Kennedy, Crane Russak, New York (1990), £32.00

The Gulf War. Edited by Hanns Maull and Otto Pick. Pinter, London (1989), ISBN 0–86187–763–2, £36.00     

The probability of survival of a subterranean target under mtensive attack

This paper deals with the analysis of a model for studying the probability of survival of a subterranean target under an intensive attack. Most of the analysis is based on the assumption that the explosions are circularly distributed about the target and that the number of explosions is known. In the last two sections it is shown what effect a relaxation of these assumptions has on the probability of survival of the target.     

Multiple common due dates

Common due date problems have been extensively discussed in the scheduling literature. Initially, these problems discussed finding a common due date for a set of jobs on a single machine. These single machine problems were later extended to finding the common due date on a set of parallel machines. This paper further extends the single machine problem to finding multiple common due dates on a single machine. For a basic and important class of penalty functions, we show that this problem is comparable to the parallel machine problem. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 293–298, 2001     

Institutional parameters that condition farmer–herder conflicts in Tivland of Benue State,Nigeria

ABSTRACT

This conceptual review examines institutional parameters that underpin farmer–herder conflicts in Tivland of Benue State, Nigeria. Anchored on the theory of New Institutionalism, it argues that tensions and conflicts between Tiv-farmers and the Fulani-herdsmen is occasioned largely by the disarticulation of the traditional institutional norms/rules of interaction by formal political institutions expressed in land use laws, West African sub-regional protocol, human rights provision of the Nigerian constitution and the Benue State law on anti-grazing. In these contrasting institutional forms, the formal political institution is prioritised by the state while farmers and herders are divided about the institutional basis of their coexistence. Farmers who host the herdsmen demonstrate preference for traditional norms of land ownership and control while the herdsmen incline towards new political/legal instruments which they interpret, purports to give them access to grazing lands and hence an alibi for rejecting institutions that contradict their claim to access spaces for pastoralism. Thus, persisting claims to the exercise of rights to freedom of movement and access to grazing land as opposed to claims to traditional rights of ownership and control of ancestral lands explain the origin and continuity of the farmer–herder conflicts in Benue state, Nigeria.     

Optimizing barge utilization in hinterland container transportation

In hinterland container transportation the use of barges is getting more and more important. We propose a real‐life operational planning problem model from an inland terminal operating company, in which the number of containers shipped per barge is maximized and the number of terminals visited per barge is minimized. This problem is solved with an integer linear program (ILP), yielding strong cost reductions, about 20%, compared to the method used currently in practice. Besides, we develop a heuristic that solves the ILP in two stages. First, it decides for each barge which terminals to visit and second it assigns containers to the barges. This heuristic produces almost always optimal solutions and otherwise near‐optimal solutions. Moreover, the heuristic runs much faster than the ILP, especially for large‐sized instances.