Tato práce se zabývá popisem stavu resource-constrained project scheduling problem. Definuje základní problém a jeho složitost. Také popisuje varianty tohoto problému. Jsou před...
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Tato práce se zabývá popisem stavu resource-constrained project scheduling problem. Definuje základní problém a jeho složitost. Také popisuje varianty tohoto problému. Jsou představeny algoritmy pro řešení RCPSP. V práci je důkladně rozebrán heuristický genetický algoritmus GARTH. Je také naznačena implementace dvou prototypů řešících RCPSP pomocí algoritmu GARTH. Je navrhnuto několik vylepšení originálního algoritmu a ty jsou vyhodnoceny.
A variety of schedule compression techniques are used to get delayed construction projects "back on tracks". This paper presents a new optimization approach to schedule crashing by relocating some of the wor...
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A variety of schedule compression techniques are used to get delayed construction projects "back on tracks". This paper presents a new optimization approach to schedule crashing by relocating some of the workers from non-critical to critical processes (changing composition of crews using the initial pool of workers) and employing additional resources. The authors describe their idea in the form of a mixed-integer linear problem. A numerical example illustrates the merits of the proposed approach. The method may become a practical support in construction scheduling decisions.
Data structures are the main ingredient to strengthen both the time complexity and the filtering power of algorithms in Constraint-Based scheduling. The TimeTable and the Profile are well-known data structures applied...
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Data structures are the main ingredient to strengthen both the time complexity and the filtering power of algorithms in Constraint-Based scheduling. The TimeTable and the Profile are well-known data structures applied to filtering algorithms for CUMULATIVE constraint. The two data structures in this paper are applied simultaneously to overload checking and edge-finding rules. The resulting rules named TimeTable Horizontally Elastic Overload Checker and TimeTable Horizontally Elastic Edge Finder rules respectively subsume the enhancement of the overload checking rule and the edge-finding rule with the individual data structure. This new edge-finding rule is relaxed after a successive application of Profile on well-selected task intervals, then TimeTable on the new horizontally elastic edge-finding rule. Potential task intervals for the edge-finding rule are selected based on two criteria (specified later in the paper) and the strong detection rule of the horizontally elastic edge finder rule of Fetgo Betmbe and Djamegni (2022) is then applied to those selected task intervals. The new horizontally elastic edge-finder rule subsumes the edge-finding rule and is not comparable to the timetable edge-finding rule. A two-phase filtering algorithm of complexity O(n2) ( n 2 ) each (where n is the number of tasks sharing the resource) is proposed for the new rule. Improvements based on the TimeTable are obtained by considering fixed parts of external tasks that overlap with the potential task intervals. The improved rule subsumes the timetable edge-finding rule, and a quadratic algorithm is derived from the previous algorithm. Experimental results, on a well-known suite of benchmark instances of resource-constrained project scheduling problems, show that the propounded algorithms are competitive with the state-of-the-art algorithms regarding running time and tree search reduction.
The paper analyses the problem of discounted cash flow maximising for the resource-constrainedprojectscheduling from the project contractor's perspective. Financial optimisation for the multi-stage project is co...
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The paper analyses the problem of discounted cash flow maximising for the resource-constrainedprojectscheduling from the project contractor's perspective. Financial optimisation for the multi-stage project is considered. Cash outflows are the contactor's expenses related to activity execution. Cash inflows are the client's payments for the completed milestones. To solve the problem, the procedure of backward scheduling taking into account contractual milestones is proposed. The effectiveness of this procedure, as used to generate solutions for the simulated annealing algorithm, is verified with use of standard test instances with additionally defined cash flows and contractual milestones.
resource-constrained project scheduling problem(RCPSP) is an important problem in research on project management. But there has been little attention paid to the objective of minimizing activities' cost with the r...
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resource-constrained project scheduling problem(RCPSP) is an important problem in research on project management. But there has been little attention paid to the objective of minimizing activities' cost with the resource constraints that is a critical sub-problem in partner selection of construction supply chain management because the capacities of the renewable resources supplied by the partners will effect on the projectscheduling. Its mathematic model is presented firstly, and analysis on the characteristic of the problem shows that the objective function is non-regular and the problem is NP-complete following which the basic idea for solution is clarified. Based on a definition of preposing activity cost matrix, a heuristic algorithm is brought forward. Analyses on the complexity of the heuristics and the result of numerical studies show that the heuristic algorithm is feasible and relatively effective.
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