O slideshow foi denunciado.
Seu SlideShare está sendo baixado. ×

Brief presentation fleet of ships optimized programming

Mais Conteúdo rRelacionado

Audiolivros relacionados

Gratuito durante 30 dias do Scribd

Ver tudo

Brief presentation fleet of ships optimized programming

  1. 1. Programa de Atualização Profissional Fleet of Ships Optimized Programming methodology summary by Gláucio Bastos, M.B.A., Ch.E.
  2. 2. Programa de Atualização Profissional abstract  target: from true characteristics of various types of fleets of ships and service vessels, cargoes and ports, it is generated a large number of ships scheduling initial solutions to serve loads in their ports, which will be refined in several optimization steps until achievement of a viable solution for greater financial return; this solution is then refined to produce the best 'timing’ decision for shipments starting, considering constraints in ports, docks availability, and stock levels in case of bulk cargo
  3. 3. Programa de Atualização Profissional neeed  during the last decades there has been an increase in competition among shipping companies, squeezing profit margins to a minimum  this situation is caused and amplified by the consolidation of the manufacturing sector, giving greater market power for cargo owners and shippers  to reduce this imbalance, there have been many mergers among shipping companies in the pursuit of scale economies gains
  4. 4. Programa de Atualização Profissional neeed  this trend of mergers and groupings leads to larger fleets, distributed geographically in extensive areas which require more efficient management  this picture of high complexity and dynamism makes uncertainties and delays inevitable phenomena in the operation of shipping, caused by factors such as adverse weather conditions, mechanical breakdowns, strikes and insufficient infrastructure, both in port and on board
  5. 5. Programa de Atualização Profissional neeed  in this context and considering the long lead times involved, it is imperative to shipping companies ensure efficiency by generating quality schedules based on advanced methods for decision support in terms of reliability and punctuality, which currently are the shortest and most effective way for achieving cost savings and generating higher profit margins
  6. 6. Programa de Atualização Profissional fleet characteristics  in shipping can be distinguished 03 different modes of operations:  industrial - the cargo owner also owns a fleet of vessels to transport it, the load is a certain amount of product to be shipped from one port to another within time windows, all charges are mandatory and must be met by the fleet available, no optional spot cargoes, the goal is to minimize costs
  7. 7. Programa de Atualização Profissional fleet characteristics  in shipping can be distinguished 03 different modes of operations:  tramp – operations that are similar to a taxi service, where ships carry available loads, is normal to an operator having some contractual charges and other options that can be met if considered profitable, the goal is to maximize profit; and  liner – operations that are similar to regular shipping lines, where the boats sail by pre-booked and published itineraries seeking to maximize their profit
  8. 8. Programa de Atualização Profissional issue description  the problem of ship schedule as analyzed here, applies to any type of fleet and can be a maximization problem of cost or profit and may involve contracts of affreightment (COA), signed to transport certain amounts or types of cargo between specified ports or among specific operations within a certain period, for an agreed payment per tonne or per service  there are cases where the fleet does not have enough capacity to meet all COAs during the planning horizon, so some loads can be met by spot charters, chartered for just a trip
  9. 9. Programa de Atualização Profissional issue description  time windows are imposed for loading and sometimes also for unloading  depending on the operation, the ships can serve single or multiple loads simultaneously with a new charging port being played and some cargo remaining on board  operations are considered with existing vessels without changes in fleet size for the short term, out of such changes are not interesting
  10. 10. Programa de Atualização Profissional issue description  fixed costs are disregarded, since do not influence the planning of optimum routes and schedules  variable costs of travel are considered mainly from consumption of fuel oil and diesel  it is considered a heterogeneous fleet of ships with special features, including different cost structures and load capacities  fees are charged for use of the port and channel, depending on the size of the vessel
  11. 11. Programa de Atualização Profissional related data  the planning horizon is 3,600 hours or 150 days  freight value (US$ / knot / m3)  general data:  buffer–times for trip and port (hr) – slack time in case of possible delays  IFO price – interm.(trip) and MDO (port) (US$ / ton)  time window for standard operation at port (hr)  cargo data:  identification, volum (m3), weight (ton)  load port, unload port  cargo time availability at loading port (hr), cargo time of arrival at unloading port (hr)
  12. 12. Programa de Atualização Profissional related data  ship data:  identification, volumetric capacity (m3), dead-weight tonnage - dwt (ton)  mean speed (knot / hr)  IFO consumption (ton / day), MDO consumption idle at port (ton / day)  port data:  identification, distance between ports of trip (knot)  produtivity (m3 / hr), port fee (US$), cargo operation fee (US$ / m3)  available ETAs for arrivings (hr)
  13. 13. Programa de Atualização Profissional solution • using MSLS heuiístics *  solution steps:  1ª: large amount (no_init) of initial solution are generated by a partially random insertion heuristic of cargo on ships schedules  2ª: a certain amount (no_quick) of the best (by profit or cost criterion) initial solutions are improved by a fast local search heuristic  3ª: it is selected a certain amount (no_extended) of the best quick local search solutions to be enhanced by a extended local search heuristic
  14. 14. Programa de Atualização Profissional results  from data of:  13 ships  50 cargoes  9 ports located among southeast USA and west Europe  the following developments in profit fleet were obtained:  to no_init = 100, no_quick = 6, no_extended = 1  init. sol.: worst = $ 628.638 / best = $ 1.127.639  fast sol.: worst = $ 1.109.300 / best = $ 1.168.316  extended sol.: $ 1.295.348  to no_init = 1000, no_quick = 14, no_extended = 4  init. sol.: worst = $ 576.334 / best = $ 1.334.752  fast sol.: worst = $ 1.183.747 / best = $ 1.334.752  extend.sol.: worst = $ 1.237.389 / best = $ 1.334.752
  15. 15. Programa de Atualização Profissional results  conclusions:  to a smaller number of initial solutions, it is evident the effective contribution of each optimization level to achieve the best final solution  for a large number of initial solutions, the optimization included in his generation algorithm is sufficient to reach the best solution, even before the next two optimization levels  so as was hit the nearest optimal solution, it can hardly be optimized and is better than that achieved with a smaller number of initial solutions, featuring the robustness of the results
  16. 16. Programa de Atualização Profissional results optimal solution – cargoes data: volums
  17. 17. Programa de Atualização Profissional results optimum solution – cargoes data: times 1.ETA load port 2.trip time 3.load port time 4.unload port time 5.reduced trip time
  18. 18. Programa de Atualização Profissional results optimum solution – scheduling result: cargoes through ships and ports 1.ship 2.load port 3.unload port
  19. 19. Programa de Atualização Profissional results optimum solution– scheduling result: routes of loaded vessels Port 2 Port 3 Port 1 Port 9 Port 5 Port 6 Port 7 Port 4 Port 8 Ship 9 Ship 10 Ship 12 Ship 1 Ship 3 Cargo 3 Cargo 5 Cargo 14 Cargo 10 Cargo 15 Ship 11 Cargo 16 Ship 2 Cargo 22 Ship 7 Cargo 24 Ship 5 Cargo 25 Ship 13 Cargo 27 Cargo 29 Cargo 31 Ship 6 Cargo 32 Ship 8 Cargo 42 Ship 4 Cargo 46
  20. 20. Programa de Atualização Profissional issue extension  if the fleet is designed to bulk transport, e.g. LNG, between liquefaction port (load) and regasification port (unload), it is considered availability of docks and stock (between maximum and minimum levels) at liquefaction port  if production exceeds contractual obligations for LNG delivery spot cargoes are sold on the market, including through other shipping company’s ships, considered as a means of controlling the inventory level without profit associated
  21. 21. Programa de Atualização Profissional issue extension  customers specify certain dates or periods - windows of time - when may or may not accept deliveries  from the time window for supplying is determined the time window for loading  delivery should occur within the time windows:  internal – periods of customer preference, and  external – besides internal comprises additional periods of a few days before and after the internal  delivery must necessarily take place inside the external window which comprises also the inner window  if delivery occurs in periods between internal and external window, there will be contractual penalties, as exemplified in the following figure
  22. 22. Programa de Atualização Profissional issue extension example of penalty cost function proportional to the square of the number of days before or after the inner window on which delivery is made - inner window is 7 days and outer window also contains 7 more days before and after the inner window
  23. 23. Programa de Atualização Profissional issue extension results  considering the same data and the solution given for the 1st part of the problem, in the extension through application of MILP method, came out the solution for minimization of penalty cost, including not only the docks restrictions but also the LNG stock in liquefaction port  in next figure are presented the optimal time partitions defined for boarding each LNG cargo within a time window with the total of 21 continuous partitions: 07 partitions of the inner window with more 07 before and 07 after completing the external window
  24. 24. Programa de Atualização Profissional issue extension results optimum solution: cargoes and their time partitions for loading start time partitions: from 01 to 21 inside external time window

×