We determine the complete set of rational integers x, y that satisfy the Thue inequality | x^3 + x^2 y - 2 x y^2 - y^3 | <= 10^6 .

Tourism is a major source of service receipts for many countries, including Taiwan. The two leading tourism countries for Taiwan, comprising a high proportion of world tourist arrivals to Taiwan, are Japan and USA, which are sources of short and long haul tourism, respectively. As it is well...

Many markets are characterized by a high level of inter-firm collaboration in R&D activity. This paper develops a simple model of strategic networks which captures two distinctive features of such collaboration activity: bilateral agreements and non-exclusive relationships. We study the effects...

The main objective of this paper is to stimulate interest in stability analysis for scheduling problems. In spite of impressive theoretical results in sequencing and scheduling, up to now the implementation of scheduling algorithms with a rather deep mathematical background in production...

In this technical note we give a short proof based on standard results in convex analysis of some important characterization results listed in Theorem 3 and 4 of [1]. Actually our result is slightly general since we do not specify the convex set X. For clarity we use the same notation for the...

This paper documents that salient features of (time series of annual) citations to scientific publications might be captured by a Bass type diffusion model. This is particularly useful as it allows for a comparison of these features across journals, across disciplines and over time. For the...

A key feature of many nonlinear time series models is that they allow for the possibility that the model structure experiences changes, depending on for example the state of the economy or of the financial market. A common property of these models is that it generally is not possible to fully...

This paper extends a fundamental result about single-item inventory systems. This approach allows more general performance measures, demand processes and order policies, and leads to easier analysis and implementation, than prior research. We obtain closed form expressions for the Laplace...

This chapter deals with forecasting sales (in units or money), where an explicit distinction is made between sales of durable goods (computers, cars, books) and sales of utilitarian products (SKU level in supermarkets). Invariably, sales forecasting amounts to a combination of statistical...

Outliers and nonlinearity may easily be mistaken. This paper uses Monte Carlo methods to examine and compare the behavior of two competing specification procedures for Smooth Transition AutoRegressive [STAR] models under various different circumstances (linear and nonlinear data generating...