Multiple Facility Location

It is not easy to extend the gravity model to multiple facilities. The main problem is that one has to decide not only the location of the multiple warehouses, but also the quantity shipped from each warehouse to the various 

Assume a set of potential sites for the multiple facilities This is more typical in practice and the IP models we discussed in Section 5.2 can then be applied directly to choose the best sites and the optimal distribution plan. Here we can take into account fixed facility cost, warehouse capacities, etc. 

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We then presented the basics of the "continuous location" models. We presented the "gravity model" for single facility location and the iterative algorithm for its solution. Extensions to the multiple facility location models were... 

You must provide information on your parent company. For purposes of Form R. a parent company is defined as the highest level company, located in the United States, that directly owns at least 50 percent of the voting stock of your company. If yourfacility is owned by a foreign entity, enter not applicable, NA, in this space. Corporate names should be treated as parent company names for companies with multiple facility sites. For example, the Bestchem Corporation is not owned or controlled by any other corporation but has sites throughout the country whose names begin with Bestchem. In this case, Bestchem Corporation would be listed as the parent company. 

Karakaya F, Canel C (1998) Underlying dimensions of business location decisions. Industrial Management Data Systems 7 321-329 Karkazis J (1989) Facilities location in a competitive environment A PROMETHEE based multiple criteria analysis. European Journal of Operational Research 42 294-304... 

Wirtschaftswissenschaftliches Studium 1 388-393 Tong H-M, Walter CK (1980) An Empirical Study of Plant Location Decisions of Foreign Manufacturing Investors in the United States. Columbia Journal of World Business 15 66-73 Tragantalerngsak S, Holt J, Ronnqvist M (2000) An exact method for the two-echelon, single-source, capacitated facility location problem. European Journal of Operational Research 123 473-489 Triantaphyllou E (2001) Two New Cases of Rank Reversals when the AHP and Some of its Additive Variants are Used that do not Occur with the Multiplicative AHP. Journal of Multi-Criteria Decision Analysis 10 11-25... 

Ranking Unit. "Ranking unit" refers to an environmental issue at a facility. The definition of a ranking unit is derived directly from its use in the Environmental Survey. A ranking unit is a composite of similar and related environmental problems located in approximately the same geographic location. There can be, and often are, multiple ranking units at each DOE site. Each ranking unit may have multiple exposure modes (e.g., multiple release locations, different release methods, different pathways). 

The problems presented above can be extended further when the facilities are not aU similar but are organized hierarchically, resulting in hierarchical facility-location problems. Similarly, when multiple, and sometimes conflicting, objectives are present, multiobjective facility-location problems are obtained. Finally, many models exist that deal with the location of undesirable facilities (e.g., hazardous waste dumps) where instead of wanting to minimize, we want to maximize some measure of the distance between the demand nodes (e.g., population centers) and the facilities. 

Abstract Transportation and facility location decisions are crucial in strategic supply chain design. Optimization models guide location decisions giving the optimal site selection under certain assumptions and constraints. It is an art to decide which model to use and how to modify the results based on the needs of a company. This chapter presents some of the important optimization models in supply chain. Mathematical formulations and solution procedures are also given. The models can be expanded for multi-echelon supply chains and/or include multiple products. 

We will save the discussion of production planning models, however, for Chapter 5, based on the similarity of that problem to the facility location and location-allocation problems discussed in that chapter. Also in Chapter 5, we introduce the notion of risk pooling, which is a means of reducing the safety stock required to support a target service level by aggregating demands across multiple sources, for example across multiple customers or customer regions supported by a single facility. 

Facility location Where a company has multiple factories (facilities) for production and factories are set for a specific product, the planner must identify which facility will be most suitable for new orders. Sometimes there may be a capacity shortage in a factory in that case the planner must decide which facility will be selected for those orders. 

This constraint is similar to constraints often used in traditional facility location models assigning each demand point exclusively to a single facility. In order to avoid nonlinearity, multiplication XjXj is replaced by the following constraints ... 

Masud AM, Ravindran AR (2008) Multiple criteria decision making. In Ravindran AR (ed) Operations research and management science handbook. CRC Press, Boca Raton Melo MT, Nickel S, Saldanha-da-Gama F (2009) Facility location and supply chain management—a review. Fur J Oper Res 196 401 12... 

Each depot can be linked to a single hub, called single-allocation, or it can be linked to more than one hub, called multiple-allocation. Both situations occur in practice. As seen in Fig. 5.7, LTL trucking networks have each depot assigned to a single break bulk terminal (hub) for load consolidation. Passenger airline networks, on the other hand, have flights scheduled from many non-hub cities to a few hubs. Also note that capacity limitations at hubs may force multiple-allocation, as seen in many facility location problems. 

Prepositioned supplies (in a general delivery warehouse) are used only when a disaster strikes. Therefore, the length of storage needed at such warehouses is uncertain. Balcik and Beamon (2008) discuss a facility location problem for humanitarian relief that integrates facility location with inventory decisions, and considers multiple items with different criticalities and response time requirements. 

A fire-resistant building is located in the facility, 75 ft (23 m) from the nearest tank, and 25 ft (7.5 m) from the nearest edge of the dike wall. The building contains tank field monitoring and control equipment, provides shelter to the operators, and also houses administrative support activities. The building is equipped with multiple means of egress. 

In addition to the criteria contained in para. PL-3.2, additional consideration shall be given to the possible consequences of a failure near areas where a concentration of people is likely, such as a church, school, multiple dwelling unit, hospital, or recreational area of an organized character in Location Class 1 or 2. If the facility is used infrequently, the requirements of para. PL-3.3.2 need not be applied. However, the depth of cover shall... 

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