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An approach to Optimization and Business rules context. Contents Optimization: Fundamental principles (maritime terminal example) Examples of Business rule effects Mathematical solutions (transportation and assignment problem)
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An approach to Optimization and Business rules context Contents • Optimization: Fundamental principles (maritime terminal example) • Examples of Business rule effects • Mathematical solutions (transportation and assignment problem) • Adopting the transportation / assignment solutions for the F-MAN asset management allocation problem National Technical University of Athens
Optimization: Fundamental principles 3 shipping lines Blue : 3000 containers / ship Red : 3000 containers / ship Green: 1200 containers / ship 2 harbor cranes / berth 20 containers / crane / hour 15 working hours / day 2 x 20 x 15 = 600 containers / berth / day National Technical University of Athens
Cost per loading unit transshipped Port cost Cost due to intensive terminal work Cw Additional energy and maintenance cost Ce Fixed operating cost Cf Port equipment utilisation factor Cost per loading unit transshipped Total cost Port cost Ship cost Port equipment utilisation factor Conflicting aspects and limitations of optimization Number of berths and/or equipment: under consideration National Technical University of Athens
Business rules: Setting FiFo service discipline FiFo priority Work progress 0% 2 harbor cranes Work progress 0% 2 harbor cranes 2 harbor cranes National Technical University of Athens
Work progress 0% 2 harbor cranes Work progress 0% 2 harbor cranes 2 harbor cranes Business rules: Service discipline favor specific customers Shipping line Blue has priority Difference form FiFo National Technical University of Athens
Work progress 0% 2 harbor cranes Work progress 0% 2 harbor cranes 2 harbor cranes Business rules: Service discipline improves port productivity Shipping line Green is served first as it has low transshipment volume Difference form FiFo National Technical University of Athens
Business rules: Service discipline favor specific customers while as secondary effect port productivity is improved Shipping line Blue has priority. The norm foresees 4 harbor cranes Assuming no productivity losses due to multi-crane operations on the same ship Work progress 0% 0 harbor cranes (1st phase) 4 harbor cranes (2nd phase) Work progress 0% 2 harbor cranes 4 harbor cranes (1st phase) 2 harbor cranes (2nd phase) Difference form FiFo National Technical University of Athens
n sinks 1 2 m sources 2 1 n sinks 1 2 sources m 2 1 Typical transportation and assignment problems Transportation problem m sources each having a single commodity ai (i=1,2 …m) n sinks each having demands bj (j=1,2,…n) xij,number of units of the product transported from source i to destination j, via the route (i,j) at cost cij per unit Cost relationship is linear ( i.e. the cost of transporting xijunits over route(i,j) is cij*xij) Assignment problem The assignment problem represents a special case of the transportation problem, where ai=1, iI, where I={1,2,…n} bj=1, jJ, where J={1,2,…n} National Technical University of Athens
Various other methodological approaches • Pickup and delivery problem with time windows • Emergency response Fleets (fire department, ambulance etc) • Real time Emergency Vehicle Dispatching and Routing • Taxi dispatching • Time dependent shortest-path algorithms A B 2 1 Heuristics Analytical solutions under assumptions National Technical University of Athens
Minimize the total transport cost under the conditions: where = availabilities and = requirements Solving the typical transportation and assignment problems National Technical University of Athens
Methodological approach for solving the transportation problem (two dimension domain) National Technical University of Athens
D) Solving the : assumption by BUSINESS RULES! Adopting the transportation /assignment solutions for the F-MAN asset management allocation problem A) Defining the cost function: (1) Geographical proximity (2) Railway line length and /or time (3) Trip time statistics B) Include uncertainties in the decision making (1) Use statistics for the required time and probabilities of non-shown (2) Generalized cost functions (including uncertainties) C) Adopting time windows by filters National Technical University of Athens