Sensitivity analysis as a means of reducing the dimensionality of a certain class of transportation problems

Sensitivity analysis of the transportation problem is developed in a way which enables reducing the dimensionality of the associated tableau. This technique is used to reduce the dimensionality of a transportation problem whose origin requirements are relatively small at the majority of origins. A long transportation problem, for which efficient solution procedures exist, results. A second application relates to the location-allocation problem. Reducing the dimensionality of such a problem, accompanied by the partial determination of the optimal solution, should prove helpful in the quest for an analytic solution to the aforementioned problem. In the meantime, reducing dimensionality greatly decreases the effort involved in solution by trial and error. Examples of the two applications are provided.     

Subcontracting State-Building

Abstract

Contemporary development assistance often takes the form of subcontracted state-building. Foreign donors hire for-profit firms to provide services and to improve or create institutions in developing countries, particularly those experiencing internal conflict. This arrangement creates two counterproductive dynamics: first, it introduces agency problems between donors, recipient states, subcontractors, and citizens; and second, it undermines the long-run development of domestic bureaucratic capacity by creating disincentives for the host government to invest. These dynamics hinder, rather than foster, the legitimacy of state institutions. This paper summarizes trends in external support to state-building since the 1970s and illustrates subcontracted state-building with examples from Colombia.     

An (s,S) inventory system with rest periods to the server

We study the (s,S) inventory system in which the server takes a rest when the level of the inventory is zero. The demands are assumed to occur for one unit at a time. The interoccurrence times between successive demands, the lead times, and the rest times are assumed to follow general distributions which are mutually independent. Using renewal and convolution techniques we obtain the state transition probabilities.     

Auxiliary procedures for solving long transportation problems

An efficient auxiliary algorithm for solving transportation problems, based on a necessary but not sufficient condition for optimum, is presented.     

Transient solution of a finite-capacity M/Ga,b/1 queueing system

In this article we consider a single-server, bulk-service queueing system in which the waiting room is of finite capacity. Arrival process is Poisson and all the arrivals taking place when the waiting room is full are lost. The service times are generally distributed independent random variables and the distribution is depending on the batch size being served. Using renewal theory, we derive the time-dependent solution for the system-size probabilities at arbitrary time points. Also we give expressions for the distribution of virtual waiting time in the queue at any time t.