The two-echelon capacitated vehicle routing problem: models and math-based heuristics

Multiechelon distribution systems are quite common in supply-chain and logistics. They are used by public administrations in their transportation and traffic planning strategies, as well as by companies, to model own distribution systems. In the literature, most of the studies address issues relating to the movement of flows throughout the system from their origins to their final destinations. Another recent trend is to focus on the management of the vehicle fleets required to provide transportation among different echelons. The aim of this paper is twofold. First, it introduces the family of two-echelon vehicle routing problems (VRPs), a term that broadly covers such settings, where the delivery from one or more depots to customers is managed by routing and consolidating freight through intermediate depots. Second, it considers in detail the basic version of two-echelon VRPs, the two-echelon capacitated VRP, which is an extension of the classical VRP in which the delivery is compulsorily delivered through intermediate depots, named satellites. A mathematical model for two-echelon capacitated VRP, some valid inequalities, and two math-heuristics based on the model are presented. Computational results of up to 50 customers and four satellites show the effectiveness of the methods developed

Simulation Testing of Aggregate Production Planning Models in an Implementation Methodology

The planning of production, inventories, and work force at an aggregate level to respond to fluctuating demands on a production system has received substantial theoretical treatment in the literature for several years. However, widespread implementation of the available analytical techniques has not occurred. The objectives of this research are to explore this implementation problem: (1) by developing a simulation model of an operating firm, (2) by using this simulation to compare the performance of aggregate production planning models, and (3) by formulating a generalized methodology for implementing quantitative planning models into the decision procedures of operating firms.

COMPARING FORECAST ACCURACY FOR EXPONENTIAL SMOOTHING MODELS OF EARNINGS‐PER‐SHARE DATA FOR FINANCIAL DECISION MAKING

This paper relates recent research in predicting accounting earnings per share (EPS) to an experiment comparing the performance of extrapolative forecasting models. The paper points out the usefulness of the results to decision‐making processes such as those used in portfolio analysis or financial management. The statistical results of the experiment point to the usefulness of the Holt‐Winter (HW) model in predicting EPS for a random sample of firms over a 20‐year horizon. For short‐term forecasting, the HW model provides relatively accurate forecasts in comparison to other methods used. HW is likely to be a costeffective alternative to more time‐consuming and expensive techniques. Copyright © 1986, Wiley Blackwell. All rights reserve

Note---Revising Forecasts of Accounting Earnings: A Comparison with the Box-Jenkins Method

The purpose of this study was to contribute to the literature concerning forecasting the time series of accounting earnings. To accomplish this objective an experiment was conducted to compare the performance of Theil's Optimal Linear Correction technique for revising quarterly Box-Jenkins and other naive model forecasts of accounting earnings against the unrevised forecasts. Several results of this study are of particular interest. First, the study indicated that the Watts-Griffin parsimonious model outperformed other firm specific Box-Jenkins models. Second, the Optimal Linear Correction produced revised forecasts that were uniformly more accurate than the original unadjusted forecasts. Finally, the naive extrapolative time series models outperformed Box-Jenkins forecasts of accounting earnings.forecasting applications: arima processes

Note--A Note on El-Shaieb's New Algorithm for Locating Sources Among Destinations

The objective of this note is (i) to identify and briefly review some references not included in [El-Shaieb, A. M. 1973. A new algorithm for locating sources among destinations. Management Sci. 20 221-231.] as well as more recent additions and (ii) to give computational comparisons of three other solution methods with that of El-Shaieb on his 30-city test data.