Transportation of handicapped persons

Transcription

1 Trnsporttion of hndicpped s Andres Reinholz Mrí Soto Mrc Sevux André Rossi DLR Institute of Solr Reserch Cologne GERMANY Lb-STICC Université de Bretgne-Sud Lorient FRANCE LOT September /25

2 A collbortion ith KERPAPE KERPAPE is medicl unit for reeduction of hndicpped people in poly-trumtology full time ptients ptients on dily progrms for severl months 2/25

3 Trnsporttion of hndicpped s Medicl units should orgnize dily the of more thn 75 ptients: from home to medicl center from medicl center to home 3/25

4 Trnsporttion of hndicpped s (cont d) Humn fctor is very importnt Specilized service Individul needs Time nd medicl constrints 4/25

5 Cost of Cost is clculted from mny fctors durtion distnce number of vehicles used type of vehicles cpcity of vehicles but most of the is done by txis... 5/25

6 description Objective Design vehicle tours to ensure dily of ptients hile minimizing the totl cost Constrints vehicle cpcity 6/25

7 Route structure Open routes: cost is pid only from home to medicl center or from medicl center to home (bck route is not pid) 7/25

8 OVRP-1 In the cse of of hndicpped s, e hve the folloing constrints: open routes (Open VRP) demnd is lys one no service time no constrints on route durtion homogeneous fleet 8/25

9 : ILS-TSMN Iterted Locl Serch is combined ith Tbu Serch nd Tbu serch is run on multiple neighborhoods Algorithm 1: ILS-TSMN Define the k mx neighborhoods N 1,N 2,,N kmx Compute initil solution s Sve best solution s s hile stopping conditions not stisfied do for k 1 to k mx do s TbuSerch(N k,s) if f(s) < f(s ) then s s end s Muttion(s ) end 9/25

10 List of neighborhoods Intr route moves Relocte 2-Opt 10/25

11 List of neighborhoods (cont d) Inter route moves Relocte (fesible) Pth-Exchnge Cross/ICross Exchnge (fesible) 2-Opt* (fesible) 11/25

12 List of neighborhoods (cont d) Inter/Intr route moves Split route (fesible) Ejection chins (not fesible) R1 R2 R1 R2 Not Fesible R1 R2 Not Fesible Repir-1 R1 R2 Fesible Repir-2 12/25

13 Similr ork on OVRP nd H. Schneider A hybrid (1+1)-evolutionry strtegy for the OVRP. In L. Di Gspero, A. Scherf, nd T. Stützle, editors, Advnces in, volume 53 of Opertions Reserch/Computer Science Interfces Series, pges Springer, M. Slri, P. Toth nd A. Trmontni. An ILP improvement procedure for the Open Vehicle Routing. Computers & Opertions Reserch 37: , U. Derigs nd K. Reuter. A simple nd efficient tbu serch heuristic for solving the open vehicle routing problem. Journl of the Opertionl Reserch Society 60: , /25

14 Comprison Hybrid (1+1)-ES vs. ILS-TSMN Hybrid (1+1)-ES (1+1)-Evolutionry Rndom serch ith multiple neighborhoods Pth exchnge neighborhoods 2-Opt relocte exchnges split route conctente routes pth exchnge using ll possible sizes ILS-TSMN Iterted Locl Serch Tbu serch ith multiple neighborhoods Ejection chins nd pth exchnge neighborhoods 2-Opt relocte split route ejection chins ith 1, 2 nodes up to the finl node 14/25

15 Comprison on OVRP instnces Clssicl instnces of OVRP from the literture Instnces Hybrid (1+1)-Evolutionry ILS-TSMN Nme Size Durtion # routes Objective CPU* # routes Objective CPU % C C C C C C C C C C C C C C F F Averge % *CPU times re scles ccording to Linpck results 15/25

16 Other instnces from Derigs nd Reuters Instnces Best Metheuristic ILS-TSMN Group Size GpLB CPU #Opt GpLB GpBest CPU #Opt A (27) % / % -0.04% /21 B (23) % / % 0.00% /19 P (24) % / % 0.02% /19 EF (12) % /9 0.24% -0.03% /9 G (8) % /25

17 OVRP-1: comprison ILP vs. ILS-TSMN Instnces ILP ILS-TSMN Nme Size Objective CPU Opt. Objective CPU % A yes A yes A yes A yes A yes A yes A yes P yes P yes P yes P yes P yes P yes B no B no A no F no C no C no C no C no C no Averge % 17/25

18 Anlysis OVRP-1 not ne but less ttention thn OVRP efficient method ILS-TSMN poer of to opertors SPLIT nd Ejection chins ILS-TSMN is comprble to Hybrid (1+1)-ES (Objective) ILS-TSMN is much better thn Hybrid (1+1)-ES (CPU) ILS-TSMN is good cndidte for OVRP-1 18/25

19 of the problem Still so mny constrints time indos service time incomptibility beteen ptients equipment for ptients Wht e tke into ccount in ne version of the problem mximum route durtion heterogeneous fleet (ith modulrity) rented vehicles 19/25

20 A ne nd more complicted problem Current fleet composed of vehicles for heelchirs vehicles for mbultory mixed vehicles for heelchirs nd mbultory With our current fleet e cn trnsport some ptients, but not ll... t loer cost thn txi or rented mini-bus our vehicles should come bck to the medicl center For ll ptients tht re not trnsported by our vehicles, e rent service 20/25

21 Ne problem definition: Mixed-VRP-1 The ne problem is Mixed Vehicle Routing ith unitry demnd (Mixed-VRP-1) Mixed routes our vehicles should mke complete routes (VRP) rented vehicles mke open routes (OVRP) Vehicle cpcity: Vehicle Cpcity Cost type heelchir mbultory fixed vrible Mini-bus W 4 0 x Mini-bus A 0 7 x Mini-bus M 4 3 x Mini-bus W (R) 4 0 x x Mini-bus A (R) 0 7 x x Mini-bus M (R) 4 3 x x Txi W (R) 1 0 x x Txi A (R) 0 1 x x 21/25

22 Solving methods Exct method n ILP model is vilble but solves only smll instnces Metheuristic currently dpting the ILS-TSMN flexible method promising results 22/25

23 An exmple of solution Only rented vehicles or txis MiniBus A (R) MiniBus W (R) MiniBus M 1 (R) MiniBus M 2 (R) Txi A (R) 23/25

24 Politicl spect Solve the problem t the politicl level convince Kerppe tht the cost could be reduced...but they do not cre, they do not py for it... txis nd rented mini-buses re pid by the socil security convince the socil security trde unions do not nt to loose positions... nd txis re relly ginst it... 24/25

25 Contcts: 25/25