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We have developed a coarse-grained (CG) model of a polymer-clay system consisting of organically modified montmorillonite nanoclay as the nanoparticle in accordance with the MARTINI forcefield. We have used mechanical properties and cleavage free energy of clay particle to respectively parameterize bonded and nonbonded interaction parameters for an organically modified montmorillonite (oMMT) clay particle where intergallery Na+ ions are replaced by tetramethylammonium (TMA) ions. The mechanical properties were determined from the slope of stress-strain curve and cleavage free energy was determined by allowing for full surface reconstruction corresponding to a slow equilibrium cleavage process. Individual dispersive and polar contributions to oMMT cleavage energy were used for determination of appropriate MARTINI bead types for CG oMMT sheet. The self-consistency of developed MARTINIFF parameters for TMA-MMT-polymer system was verified by comparing estimates for select structural, thermodynamic, and dynamic properties obtained in all-atomistic simulations with that obtained in coarse-grained simulations. We have determined the influence of clay particle on properties of three polymer melts (polyethylene, polypropylene, and polystyrene) at two temperatures to establish transferability of the developed parameters. We have also shown that the effect of clay-polymer interactions on structure-property relationships in this nanocomposite system is well captured by Rosenfeld's excess entropy scaling., Comment: 45 pages, 7 figures, 2 tables

Estimation is one of the most critical areas in software project management life cycle, which is still evolving and less matured as compared to many other industries like construction, manufacturing etc. Originally the word estimation, in the context of software projects use to refer to cost and duration estimates only with software-size almost always assumed to be a fixed input. Continued legacy of bad estimates has compelled researchers, practitioners and business organizations to draw their attention towards another dimension of the problem and seriously validate an additional component, viz. size estimation. Recent studies have shown that size is the principal determinant of cost, and therefore an accurate size estimate is crucial to good cost estimation. Improving the accuracy of size estimates is, therefore, instrumental in improving the accuracy of cost and schedule estimates. Moreover, software size and cost estimates have the highest utility at the time of project inception, when most important decisions (e.g. budget allocation, personnel allocation, etc). are taken. The dilemma, however, is that only high-level requirements for a project are available at this stage. Leveraging this high-level information to produce an accurate estimate of software size is an extremely challenging and high risk task. This study acknowledges the presence and effect of risk in any software estimate and offers pragmatic strategies for risk mitigation.

It is well known fact that was phrased by famous quality scholar P.B. Crosby that it is always cheaper to do the job right the first time. However, this statement must be reconsidered with respect to software development projects, because the concept of quality and associated costs measurements in software engineering discipline is not as matured as in manufacturing and other fields of the industry. Post delivery defects (i.e. software bugs) are very common and integral part of software industry. While the process of measuring and classifying quality cost components is visible, obvious and institutionalized in manufacturing industry, it is still evolving in software industry. In addition to this, the recommendations of British standard BS-6143-2:1990 for classifying quality-related costs into prevention costs, appraisal costs, and failure costs have been successfully adopted by many industries, by identifying the activities carried out within each of these categories, and measuring the costs connected with them, software industry has a long-way to go to have the same level of adoption and institutionalization of cost of quality measurements and visibility. Cost of Quality for software isn't the price of creating a quality software product or IT-service. It's actually the cost of NOT creating a quality software product or IT-service. The chronic affliction of majority of software development projects that are frequently found bleeding with cost overruns, schedule slippage, scope creep and poor quality of deliverables in the global IT industry, was the trigger for this research work. Lessons learnt from this study offer valuable prescriptive guidance for small and medium software businesses, who can benefit from this study by applying the same for their quality improvement initiatives using CoQ-metric, to enhance the capability and maturity of their SDLC-project performance., Comment: arXiv admin note: text overlap with arXiv:1202.2506 by other authors without attribution

Growth in the number of PMOs established by the industry over last decade and ever growing body of literature on PMO related research in academia is a clear indication that there is very clear interest of researchers, practitioners and industries across the globe to understand and explore value propositions of PMO. However, there is still a lack of consensus on many critical aspects of PMOs. While there are many PMOs being established, but there are also many being closed and disbanded, which is definitely a matter of concern. In industry environment, a narrow majority of PMOs are well-regarded by their organizations and are seen as contributing business value, many of the others are still struggling to show value for money and some are failing, causing a high mortality rate among PMOs. This paper is the result of a study undertaken to get a deeper understanding of factors that may be causing mortality and failure of PMOs. Post Implementation Reviews of 4-failed & 3-challenged PMOs in IT-Industry were carried out with concerned Project Managers & PMO-staff, using grounded theory research method, with support from the concerned enterprise from IT-Industry.