About VINNOVA VINNOVA, the Swedish Agency for Innovation Systems, integrates research and development in technology, transport, communication and working life. VINNOVA´s mission is to promote sustainable growth by developing effective innovation systems and funding problem-oriented research. Through its activities in this field, VINNOVA aims to make a significant contribution to Sweden´s develo...

An EOQ (Economic Order Quantity) model for a deteriorating item with quadratic demand pattern and quadratic holding cost and constant deterioration rate is considered in this paper. In addition, shortages and partial backlogging are allowed. It is assumed that the backlogging rate acts as not only a variable, but also depends on the length of the waiting time up to next replenishment during the...

hy do firms and inventors tend to locate in dense, costly areas? One intriguing hypothesis is that such geographic clustering lets them benefit from local knowledge spillovers. As nobel laureate robert Lucas has noted, the benefits of one person’s knowledge spilling over to others play a central role in economic growth and the existence of cities: “What can people be paying Manhattan or downtow...

In this paper, two economic production quantity (EPQ) models are proposed for deteriorating/imperfect items with rework process. The production process is imperfect, and imperfect quality items are reworked to become serviceable. At the same time, the remaining good quality items may deteriorate. The inspection of deteriorated items is also imperfect, so that deteriorated items may be sold to c...

R etailers must constantly strive for excellence in operations; extremely narrow profit margins leave little room for waste and inefficiency. This article reports a retailer’s challenge to balance transportation, shelf space, and inventory costs. A retailer sells multiple products with stochastic demand. Trucks are dispatched from a warehouse and arrive at a store with a constant lead time. Eac...

Within the economic production quantity (EPQ) framework, the main purpose of this paper is to deal with Chung and Huang’s model (2003) and extend Chung and Huang’s model (2003) by considering the unit selling price higher than the unit purchasing cost using the algebraic method to determine the optimal inventory replenishment policy for the retailer under trade credit. This paper provides this ...

Inventory models with imperfect quality items are studied by researchers in past two decades. Till now none of them have considered the effect of substitutions to cope up with shortage and avoid lost sales. This paper presents an EOQ approach for inventory system with shortages and two types of products with imperfect quality by one way substitution. Our model provides significant advantage for...

The demand pattern for most perishable products varies during their life cycle in the market. These variations must be properly reflected in inventory management in order to prevent unnecessary stock-out or excess inventory with associated increase in cost. In this paper, a multi-period economic order quantity (EOQ) model for managing the inventory of perishable items having varying demand patt...

Knowledge-infused clusters, involving governmental and university, as well as firm actors are the epitome of contemporary economic development strategy. The role of Southern Oregon University (SOU) in the inception of the Oregon Shakespeare Festival (OSF) gives rise to a model for education-focused universities to play a significant role in local economic development through creation of cultura...

This paper addresses the issue of causality in the relationship between various types of institutions—namely, political and economic freedom—and long-run economic growth. It is shown that existing empirical studies of these relationships provide evidence of correlation, but not causation. Granger causality tests of freedom vs. growth, and freedom vs. investment are conducted using aggregate mea...