Optimization Model for Determination of Characteristics for the Development of Construction Project Involving Labor Forces

Abstract This paper presents a novel approach for determining the best combination of groynes in terms of their number, lengths and positions for controlling bank erosion. The vulnerable bank is considered to be protected if a very small value of water flow speed is achieved on the near bank area. A linked simulation–optimization model is developed in this regard which minimizes the total construction cost of the groyne project. At the same time, a constraint in terms of low flow speed in a predefined zone is incorporated, which helps in bank erosion prevention. In the simulation model, the depth-averaged shallow water equations are solved using a finite difference scheme. The optimization problem is formulated in three different approaches to tackle different types of in situ field problems. Genetic algorithm (GA) is used to solve the optimization problem. The proposed optimization model is used in two hypothetical test cases including one straight channel and one meandering channel. The results obtained with all the three formulations are found to be logical and establish the potential of the present model for application in real cases.

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Critical Safety Factors in Construction Projects

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.255-260.3921 ◽

2011 ◽

Vol 255-260 ◽

pp. 3921-3927 ◽

Cited By ~ 2

Author(s):

Gholamreza Heravi ◽

Hamed Nabizadeh Rafsanjani

Keyword(s):

Construction Projects ◽

Safety Management ◽

Construction Project ◽

Limited Resources ◽

Safety Engineering ◽

Safety Factors ◽

Work Related ◽

Definition Of ◽

Project Lifecycle

Safety is very important aspects of construction projects which are the most hazardous endeavors have many work-related injuries and accidents. Accordingly, safety factors must be considered in project lifecycle from beginning of a project to its end. To improve project safety, the definition of safety factors and determination of their importance are necessary. In some of the previous researches several safety factors are introduced. In this paper, safety factors in construction project are reviewed and categorized as well as an exhaustive classified catalogue of critical safety factors in construction project which don't have unnecessary details is developed. The identification of the critical safety factors which are categorized in four main groups consists of safety approach, safety engineering, safety management and safety on construction site will enable appropriate allocation of limited resources.

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RESILIENCE-COST TRADEOFF SUPPLY CHAIN PLANNING FOR THE PREFABRICATED CONSTRUCTION PROJECT

Journal of Civil Engineering and Management ◽

10.3846/jcem.2021.14114 ◽

2021 ◽

Vol 27 (1) ◽

pp. 45-59

Author(s):

Hong Zhang ◽

Lu Yu

Keyword(s):

Supply Chain ◽

Optimization Model ◽

Construction Project ◽

Transportation Cost ◽

Planning Problem ◽

Multi Objective Optimization ◽

Planning Stage ◽

Multi Objective ◽

Construction Schedule

Delivery of the prefabricated components may be disrupted by low productivity and various of traffic restrictions, thus delaying the prefabricated construction project. However, planning of the prefabricated component supply chain (PCSC) under disruptions has seldom been studied. This paper studies the construction schedule-dependent resilience for the PCSC plan by considering transportation costs and proposes a multi-objective optimization model. First, the PCSC planning problem regarding schedule-dependent resilience and resultant transportation cost is analyzed. Second, a quantification scheme of the schedule-dependent resilience of the PCSC plan is proposed. Third, formulation of the resilience-cost tradeoff optimization model for the PCSC planning is developed. Fourth, the multi-objective particle swarm optimization (MOPSO)-based method for solving the resilience-cost tradeoff model is presented. Finally, a case study is presented to demonstrate and justify the developed method. This study contributes to the knowledge and methodologies for PCSC management by addressing resilience at the planning stage.

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On Sequential Decision Problems with Constant Costs of Observation

Stochastic Processes and Models in Operations Research - Advances in Logistics, Operations, and Management Science ◽

10.4018/978-1-5225-0044-5.ch013 ◽

2016 ◽

pp. 218-229

Author(s):

Sören Christensen ◽

Albrecht Irle

Keyword(s):

Portfolio Optimization ◽

Optimal Stopping ◽

Optimization Model ◽

Decision Problems ◽

Solution Technique ◽

Sequential Decision ◽

Sequential Decision Problems ◽

Optimal Stopping Problems ◽

Portfolio Optimization Model

We present a solution technique for optimal stopping problems with constant costs of observation in a diffusion setting. Such problems arise naturally, e.g., in Wald's type sequential decision problems and the Portfolio optimization model by Morton and Pliska. The main result is that the treatment of such problem boils down to the determination of the maximum points of a class of explicitly given functions. The findings are illustrated by a variety of examples and generalized to random costs of observation.

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