Freight and Goods Movement

Physical Distribution from a Warehouse

Carlos Daganzo
1983

This paper studies the costs involved in distributing items from a warehouse or depot to randomly scattered customers on a day-to-day basis. Two trade-offs are explored simultaneously. The first one arises because by accumulating large inventories at the depot it is possible to build more efficient distribution tours. This trade-off has already been explored for both distribution of goods (Burns et al., 1983) and passengers (Daganzo et al., 1977; Hendrickson, 1978). Another tradeoff, which involves the length of individual vehicle tours (...

The Distance Traveled to Visit N Points with a Maximum of C Stops per Vehicle: An Analytic Model and an Application

Carlos Daganzo
1984

The purpose of this paper is to develop a simple formula to predict the distance traveled by fleets of vehicles in physical distribution problems involving a depot and its area of influence. Since the transportation cost of operating a break-bulk terminal (or a warehouse) is intimately related to the distance traveled, the availability of such a simple formula should facilitate the study of more complex logistics problems. A simple manual dispatching strategy intended to mimic what dispatchers do, but simple enough to admit analytical modeling is presented. Since the formulas agree rather...

Vehicle-Miles for a Freight Carrier with Two Capacity Constraints

Hall, Randolf W.
Carlos Daganzo
1985

The amount of freight that can be fit on a vehicle depends on the vehicle's weight capacity and volume capacity. In this paper mathematical equations are developed for evaluating the impact of weight capacity and volume capacity on total vehicle-miles. It is shown that the number of vehicle loads needed to carry a large amount of material is minimized when all vehicles are filled to the same capacity constraint. This is accomplished by mixing light items with heavy items in vehicle loads. Following this policy can reduce the number of vehicle loads and vehicle-miles. Under ideal...

Analyzing Trade-offs Between Transportation, Inventory and Production Costs on Freight Networks

Blumenfeld, Dennis E.
Burns, Lawrence D.
Diltz, J. David
Carlos Daganzo
1985

The purpose of this paper is to determine optimal shipping strategies (i.e. routes and shipment sizes) on freight networks by analyzing trade-offs between transportation, inventory, and production set-up costs. Networks involving direct shipping, shipping via a consolidation terminal, and a combination of terminal and direct shipping are considered. This paper makes three main contributions. First, an understanding is provided of the interface between transportation and production set-up costs, and of how these costs both affect inventory. Second, conditions are identified that indicate...

Physical Distribution from a Warehouse: Vehicle Coverage and Inventory Levels

Carlos Daganzo
Newell, Gordon F.
1985

This paper studies the costs involved in distributing items from a warehouse or depot to randomly scattered customers on a day-to-day basis. Two trade-offs are explored simultaneously. The first one arises because by accumulating large inventories at the depot it is possible to build more efficient distribution tours. This trade-off has already been explored for both distribution of goods (Burns et al., 1983) and passengers (Daganzo et al., 1977; Hendrickson, 1978). Another tradeoff, which involves the length of individual vehicle tours (Clarens and Hurdle, 1975), balances the inventory...

Distribution Strategies that Minimize Transportation and Inventory Costs

Burns, Lawrence D.
Hall, Randolph W.
Blumenfeld, Dennis E.
Carlos Daganzo
1985

This paper develops an analytic method for minimizing the cost of distributing freight by truck from a supplier to many customers. It derives formulas for transportation and inventory costs, and determines the optimal trade-off between these costs. The paper analyzes and compares two distribution strategies: direct shipping (i.e., shipping separate loads to each customer) and peddling (i.e., dispatching trucks that deliver items to more than one customer per load). The cost trade-off in each strategy depends on shipment size. Our results indicate that, for direct shipping, the optimal...

Supplying a Single Location from Heterogeneous Sources

Carlos Daganzo
1985

This paper studies how items with different characteristics, and being demanded at different rates from a finite number of supply points, should be transported to a common destination. The items may differ in size and value, and the origins may differ in their spatial distribution, the kind of items they produce and the production rate. Depending on the application context, the common destination can represent a warehouse, a factory, a military base, a break-bulk terminal, a port or another kind of transportation terminal. Different kinds of items may call for separate transportation...

Distributing Nonstorable Items Without Transshipments

Han, Anthony F. W.
Carlos Daganzo
1986

The research reported in this paper attempted to find optimal strategies for distributing items from one depot to many demand points without transshipments and within a limited amount of time. The objective was to find a near optimal partition of the region supplied by the depot into districts (the zones containing the points visited by one delivery route) and corresponding shipment sizes and costs. Initially, the average distribution cost per demand point on a single delivery route was studied using expressions that relate route length to the dimensions of a delivery district. Two...