Abstract: Cash shortage is one of the most dangerous problems that may appear while projects are in progress. Inadequate cash flows force the companies to take short term or long term loans and in some cases companies end up being bankruptcy. In this study the planned and actual cumulative percentages of cash flows and work progress which are represented using S-curves are used as the basis for analyzing cash flows using artificial neural networks. The planned and actual cash flows are imported to MATLAB and are trained using the developed cash flow analysis model. The results of this analysis will assist the contractor in identifying the down fall of the cumulative percentage of actual cash flows with respect to the percentage of the work completed based on which the contractor can manage the cash flows to maintain work continuity, prevent interruption of project and take precautions to protect the company from being bankruptcy

• Publication Date: 02-Jun-2014
• DOI: 10.15224/978-1-63248-012-5-70
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Abstract: Frictional behaviour becomes main study in machining, especially for ball screw driven positioning stage. This paper presents friction behaviour analysis in pre-sliding regime using various mathematical models that produce a sigmoid like curve. In pre-sliding regime, friction behaviour is described while axes moving at relatively low velocity. Furthermore, a smooth continuous curve is needed in the transition between sliding regimes. Generalized Maxwell Slip (GMS) model is known model that well describes the friction behaviour at pre-sliding regime. Sigmoid like function is proposed as a significant parameter in modified GMS. The numerical simulation was performed to show the influences and effects for each sigmoid like curve. The result analysis leads to the development of an adaptive friction compensation model

• Publication Date: 02-Jun-2014
• DOI: 10.15224/978-1-63248-012-5-71
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