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An issue has arisen with regard to which of the schedule generation schemes will perform better for an arbitrary instance of the resource-constrained project scheduling problem (RCPSP), which is one of the most challenging areas in construction engineering and management. No general answer has been given to this issue due to the different mechanisms between the serial scheme and the parallel scheme. In an effort to address this issue, this paper compares the two schemes using a permutation-based Elitist genetic algorithm for the RCPSR Computational experiments are presented with multiple standard problems. From the results of a paired difference experiment, the algorithm using the serial scheme provides better solutions than the one using the parallel scheme. The results also show that the algorithm with the parallel scheme takes longer to solve each problem than the one using the serial scheme. DOI: 10.1061/(ASCE)0733-9364(2010)136:2(160) CE Database subject headings: Optimization; Project management; Scheduling; Algorithms; Comparative studies. Author keywords: Optimization; Project management; Scheduling; Resource; Genetic algorithms; Comparative study.

The resource-constrained project scheduling problem (RCPSP) has received the attention of many researchers because its general model can be used in a wide variety of construction planning and scheduling applications. The exact procedures and priority-rule-based heuristics fail to search for the optimum solution to the RCPSP of large-sized project networks in a reasonable amount of time for successful application in practice. This paper presents a permutation-based elitist genetic algorithm for solving the problem in order to fulfill the lack of an efficient optimal solution algorithm for project networks with 60 activities or more as well as to overcome the drawback of the exact solution approaches for large-sized project networks. The proposed algorithm employs the elitist strategy to preserve the best individual solution for the next generation so the improved solution can be obtained. A random number generator that provides and examines precedence feasible individuals is developed. A serial schedule generation scheme for the permutation-based decoding is applied to generate a feasible solution to the problem. Computational experiments using a set of standard test problems are presented to demonstrate the performance and accuracy of the proposed algorithm. CE Database subject headings: Optimization; Construction management; Scheduling; Algorithm.

Abstract: Planning is an essential function of project management. Yet, many small- and medium-sized contractors do a relatively poor job of operational planning. Better prebid plans will reduce costs, shorten schedules, and improve labor productivity. Unfortunately, the published literature offers little guidance for smaller contractors on what constitutes effective planning. Most papers describe planning as a macrolevel process for owners. Most emphasize scope definition for industrial projects. This paper describes a microlevel planning process for contractors. It consists of eight steps which are: (1) assess contract risks; (2) develop a preliminary execution plan; (3) develop site layout plans; (4) identify the sequences that are essential-to-success; (5) develop detailed operational plans; (6) develop proactive strategies to assure construction input into design; (7) revise the preliminary plan; and (8) communicate and enforce the plan. The entire process is illustrated with a case study project and is fully illustrated with figures which show how to integrate the work of multiple contractors, keep key resources (crews or equipment) fully engaged with no downtime, provide time buffers so the work of follow on crews can be efficiently done, expedite the schedule using multiple work stations and concurrent work, ways to communicate the work plan to the superintendent and foremen, and how to assess the feasibility of various work methods. The steps are easy to understand and implement. They will yield immediate positive results. DOI: 10.1061/(ASCE)0733-9364(2007) 133:8(542) CE Database subject headings: Construction costs; Productivity; Labor; Scheduling; Contractors; Planning.

Wheeler, M. (2005). Reconstructing the Cognitive World. Cambridge, MA: MIT Press. Michael Wheeler's Reconstructing the Cognitive World is a good read for phenomenological psychologists and those from all the various [...]

This research study introduces the development of a method for measuring and analyzing the project level productivity (PLP) of all project activity over the life of the project. A key aspect of the measurement method was the development of a process to combine multiple simultaneous work activity productivity into a global productivity value for the project as a whole. Three case studies, including the collection of thousands of productivity values, were performed on highway construction projects to demonstrate the validity of the analysis method. Results indicate that productivity can be measured and analyzed at the project level based upon the field data of construction operations. DOI: 10.1061/(ASCE)0733-9364(2006)132:3(314) CE Database subject headings: Productivity; Highway construction: Project management; Research.

Globus, G. (2003). Quantum closures and disclosures: Thinking-together post-phenomenology and quantum brain dynamics. Erdenheim, PA: John Benjamins, 198 pp., ISBN 1-58811-371-X, $48.95 (paper). This is not your father's quantum brain [...]