Research On Multi-mode Resource Constrained Project Scheduling Probelm With Considering Spatial Resource

With the development of social economy,the problem of project scheduling widely exists in various industries.How to make reasonable arrangements for activities to ensure that the project is delivered on schedule under the conditions of ensuring quality and safety with limiteation of resources,and complete the original plan and goals.That is,the Resource Constrained Project Scheduling Problem,RCPSP and its branches are research questions which have always received much attention.In the engineering field,due to the complexity of the engineering project itself,the research of RCPSP issues and its branch projects is an important content in the field of engineering project management research.Multi-mode Resource Constrained Project Scheduling Problem,MRCPSP,as one of the branches of RCPSP,considers more practical problems in the construction and production of enterprises,that is,facing different resource supply,there is often more than one mode of execution for each activity.The MRCPSP problem considers different ways of resource allocation for project execution,which can give managers more decision-making space.Therefore,this paper conducts research based on the MRCPSP model,and aims to guide the solution of practical problems in engineering project scheduling.In the past research on resource-constrained project scheduling problems,due to algorithmic constraints,people often consider only three typical resources: people,materials,and machines when they consider resource types,or convert them into funds and construction periods,so as to be constraints during project scheduling.However,in the process of on-site construction,the supply and utilization of another type of resources has an important impact on the safety and quality of engineering projects—space resources.Poor construction quality,rework,and even safety accidents caused by space collisions between different activities at the construction site will seriously affect the smooth progress of the project and cause significant losses.Therefore,based on the original MRCPSP problem model,this paper considers the limited space resources on the construction site as one of the constraints in the project scheduling process.In this paper,a dual-objective MRCPSP mathematical model is established with the shortest duration and minimum average space congestion,and the algorithm design is based on the NSGA-II algorithm,which is widely used and solves multi-objective optimization problems.It aims to generate a project schedule without space collision.In addition,the setting of the dual objective can generate different schemes,giving decision makers more space from the two dimensions of time and construction site management.Aiming at the characteristics of space resources,this paper analyzes the existing space requirements of the construction site,classifies the space requirements of activities,and then uses the space-time matrix based on the construction site space to innovatively propose different space requirements,utilizing different assignments of the value in matrix to store space requirements information for activities.In addition,the space occupancy of the construction site is obtained through the calculation of the space resource demand matrixs,and the average space congestion is also calculated.Finally,this article uses the Geatpy toolkit to programmatically implement a calculation example in the Python language environment,and proves the effectiveness of the algorithm.This paper considers the requirements of active space resources in the scheduling stage,and uses the space-time matrix to creatively propose different assignment methods to allow the project scheduling stage to consider the complex threedimensional spatial information.This research broadens the research field of RCPSP problem,the establishment of a dual-objective model with the shortest duration and the minimum average spatial congestion,and the generation of different schemes,allowing managers to weigh the two for different realities and then make scheduling scheme choices,therefore it can be more practical to guide the construction scheduling.