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This study investigates a novel approach both to precisely plan for project execution and to monitor execution status in near real-time. In this approach, two lean construction techniques-such as pull planning and integrated project delivery-are combined with the fine-grained planning and near real-time monitoring of the executed work. In order to plan for and monitor the flow of work, work packages are defined at the smallest discernible amount of work, the task. Work packages are divided by unique location sectors, and hence further discretized. Deviations based on predictions of completed work are proactively reported and assessed in near realtime. In addition, productivity ratios for completed projects are utilized to pre-qualify contractors for future project endeavors and to generate accurate bidding information. Thus, an emphasis to stabilize workflow is at the core of the proposed fine-grained production planning and near real-time monitoring approach. Through an intervention test in a facility project, a comparison of relevant metrics is used to quantify and validate the impact of the novel approach.

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Permanent magnet synchronous motors (PMSMs) are increasingly used in high performance variable speed drives of many industrial applications. PMSM has many features, like high efficiency, compactness, high torque to inertia ratio, rapid dynamic response, simple modeling and control, and maintenance free operation. Presence of position sensors presents several disadvantages, such as reduced reliability, susceptibility to noise, additional cost and weight and increased complexity of the drive system. For these reasons, the development of alternative indirect methods for speed and position control becomes an important research topic. Advantages of sensorless control are reduced hardware complexity, low cost, reduced size, cable elimination, increased noise immunity, increased reliability and decreased maintenance. The key problem in sensorless vector control of ac drives is the accurate dynamic estimation of the stator flux vector over a wide speed range using only terminal variables (currents and voltages). The difficulty comprises state estimation at very low speeds where the fundamental excitation is low and the observer performance tends to be poor. Moreover, the noises of system and measurements are considered other main problems. This paper presents a comprehensive study of the different sliding mode observer methods of speed and position estimations for sensorless control of PMSM drives.

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