Web log analysis: a review of a decade of studies about information acquisition,inspection and interpretation of user interaction

In the last decade, the importance of analyzing information management systems logs has grown, because log data constitute a relevant aspect in evaluating the quality of such systems. A review of 10 years of research on log analysis is presented in this paper. About 50 papers and posters from five major conferences and about 30 related journal papers have been selected to trace the history of the state-of-the-art in this field. The paper presents an overview of two main themes: Web search engine log analysis and Digital Library System log analysis. The problem of the analysis of different sources of log data and the distribution of data are investigated.     

Cutting force and tool wear of single diamond-coated bead

The aim of this study is to optimize stone materials cutting by diamond wire cutter. Attention is focused on the study of the cutting process through sintered diamond-encrusted beads used to work granite. This study is aimed at understanding the interaction between the bead and the material; in detail, experimental equipment was designed to test individual diamond-coated beads, and it was installed on a numerical-control work center. This equipment made it possible to test an individual bead and, in particular, to determine its cutting power and its main force components on the basis of various process parameters, such as cutting velocity (V _t) and feed velocity (V _a). The test runs also made it possible to determine wear on each bead on the basis of process parameters. This is a necessary first step to be able, in the future, to optimize the tool and the cutting process.     

e-Infrastructures for e-Science: A Global View

In the last 10?years, a new way of doing science is spreading in the world thank to the development of virtual research communities across many geographic and administrative boundaries. A virtual research community is a widely dispersed group of researchers and associated scientific instruments working together in a common virtual environment. This new kind of scientific environment, usually addressed as a ??collaboratory??, is based on the availability of high-speed networks and broadband access, advanced virtual tools and Grid-middleware technologies which, altogether, are the elements of the e-Infrastructures. The European Commission has heavily invested in promoting this new way of collaboration among scientists funding several international projects with the aim of creating e-Infrastructures to enable the European Research Area and connect the European researchers with their colleagues based in Africa, Asia and Latin America. In this paper we describe the actual status of these e-Infrastructures and present a complete picture of the virtual research communities currently using them. Information on the scientific domains and on the applications supported are provided together with their geographic distribution.     

Uncertainty Assessment of a Water-Quality Model for Ephemeral Rivers Using GLUE Analysis

Every model is, by definition, a simplification of the system under investigation. Although it would be desirable to reduce the gap between the simulated and the observed behaviors of the system to zero, this reduction is generally impossible owing to the unavoidable uncertainties inherent in any modeling procedure. Uncertainty analyses can provide useful insights into the best model approach to be used for obtaining results with a high level of significance and reliability. The evaluation of parameter uncertainties is necessary for calibration and for estimating the impact of these uncertainties on model performance. In this context, the uncertainty of a river water-quality model developed in previous studies is presented. The main goal is to gain insights into the modeling approaches concerning small rivers. Previous works generally focused on modeling the large river while neglecting the small one. Following a model calibration, the model uncertainty has been assessed by means of the generalized likelihood uncertainty estimation (GLUE). The results showed that the biological process related to the biological oxygen demand (BOD) removal influenced mainly by the parameters characterizing deoxygenation and nitrogen removal. On the other hand, the biological processes related to nitrogen removal were influenced not only by the parameters related to the nitrogen removal but also to oxygen concentration. The application of the GLUE methodology shows that the river quality model considered is suitable for simulating the important processes involved. Uncertainty bounds showed different amplitudes with respect to the pollutant species considered. In particular, the oxygen uncertainty bounds were narrower with respect to the other model components suggesting much attention must be paid to both model algorithms and quality data to be gathered. The study confirmed the suitability of the GLUE methodology as a powerful tool as a simplified screening methodology to assess uncertainty.     

Improving die casting processes through optimization of lubrication

Lubrication plays a significant role among the processes that affect aesthetic quality in die casting. Nevertheless, comprehensive investigations are still missing in literature. In this paper, the effect of lubrication is investigated and optimized, by focusing on its influence on the die temperature. Indeed, since the surface quality of castings is related to the interaction between melt and die, lubrication allows ejection of castings without generating defects and cooling of the die, by preserving its surface. Hence, the die temperature should be accurately selected and spraying should be improved to achieve the optimal temperature. In the experimentation proposed, the lubricant release agent percentage and the lubrication duration have been varied to trade-off between some conflicting effects, while making the die temperature approach the ‘Nukiyama point’. At the same time, reduction of the cycle time has been obtained. The results corroborate the approach, since defects are reduced after optimization.