A new approach to sustainable project scheduling for public institutions is proposed. The based on experts’ opinions three aspects of sustainability activities (human resources consumption, material consumption and negative influence local communities), expressed by means Z-fuzzy numbers. fuzzy bicriterial optimization model proposed, whose objective obtain a schedule an acceptable degree durat...

this paper presents a mathematical model for a flow shop scheduling problem consisting of m machine and n jobs with fuzzy processing times that can be estimated as independent stochastic or fuzzy numbers. in the traditional flow shop scheduling problem, the typical objective is to minimize the makespan). however,, two significant criteria for each schedule in stochastic models are: expectable m...

The Crew Rostering Problem considers the assignment of the crew staff to a set of pairings covering all the scheduled flights so that operations costs are minimized while its solution must meet hard constraints resulting from the safety regulations of Civil Aviation as well as from the airlines’ internal agreements. Another goal is of the highest interest for airlines: since the overall satisfa...

Scheduling problem for repetitive construction projects involves three conflicting objectives. These objectives are project duration, project total cost, and project total interruption time. This paper presents a multi-objective fuzzy linear programming model (FLP) for resolving this problem. Literature concerned with scheduling problems for repetitive construction projects was reviewed. Multi-...

Several approaches are followed in project scheduling under multiple resources. Typically, priorities for each activity are obtained using qualitative data. In this paper, both quantitative and qualitative data are considered in a fuzzy environment. A Fuzzy Analytical Hierarchy process is developed to obtain weightages for each activity that needs multiple resources. Fuzzy AHP efficiently handl...

In this paper a new method based on fuzzy theory is developed to solve the Project Resource Leveling Problem in fuzzy environment. Resource Leveling Problem attempts to minimize the resource usage fluctuations in project plan. Assuming that the duration of activities and resource requirements are fuzzy, in this method we compute several project characteristics such as earliest times, latest tim...

extensive research has been devoted to resource constrained project scheduling problem. however, little attention has been paid to problems where a certain time penalty must be incurred if activity preemption is allowed. in this paper, we consider the project scheduling problem of minimizing the total cost subject to resource constraints, earliness-tardiness penalties and preemption penalties, ...

In this paper we shall represent strategic planning problems by dynamic decison trees, in which the nodes are projects that can be deferred or postponed for a certain period of time. Using the theory of real options we shall identify the optimal path of the tree, i.e. the path with the biggest real option value in the end of the planning period.

The paper aims to present an application of constraint programming techniques for project portfolio scheduling taking into account the imprecision in activity duration and cost. Data specification in the form of discrete α-cuts allows combining distinct and imprecise data, and implementing a constraint satisfaction problem with the use of constraint programming. Moreover using α-cuts, optimisti...

In this paper, a new fuzzy logic-based approach to production scheduling in the presence of uncertain disruptions is presented. The approach is applied to a real-life problem of a pottery company where the uncertain disruption considered is glaze shortage. This disruption is defined by two parameters that are specified imprecisely: number of glaze shortage occurrences and glaze delivery time. T...