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Due to the increasing complexity of software systems, there is a growing need for automated and scalable software synthesis and analysis. In the last decade, active research in the formal methods community brought interesting results and valuable tools. However, there are still challenges to face and hard problems that need to be solved. We briefly outline some recent trends, and review some of the latest achievements, introducing six papers selected from the 20th International Conference on Tools and Algorithms for the Construction and Analysis of Systems (TACAS 2014). [ABSTRACT FROM AUTHOR]

This paper focuses on the application of principal component analysis (PCA) to thoroughly analyse and interpret multidimensional data from a cold rolling process. The analysis includes the effects of variables on the final properties of strips in a cold rolling mill. Unscrambler software was used to analyse and identify hidden variables. Variable correlations were also used to derive correlations between the control parameters. The results of this research will be used to improve the selection of material in order to reduce the occurrence of defects in the cold rolling process and to improve the adjustment of the set points that are performed in every pass or section of the cold rolling process. The hot rolled strips that enter the cold rolling mill are made of different materials and are produced by different strip manufacturers. Some strips break during the thickness reduction process in the cold rolling mill. This paper focuses on two possible causes of breakage: non-uniform strip material properties and failures in the rolling mill process. Two types of rolled strips (those that break and those that do not break) were compared to identify causes of breakage. The results indicate that breakages are caused by material or process failures. PCA was applied to the dataset in order to identify and analyse the relationships between the variables in the process. This information was used to interpret and diagnose the process behaviour. Swarm analysis and relating observations to process behaviour were able to distinguish between different start-up conditions, and between desirable and undesirable process conditions. [ABSTRACT FROM AUTHOR]

Flexible manufacturing system (FMS) is one of the solutions that enables any manufacturing system to withstand changing requirements of the market. An FMS consists of different automated workstations, material handling devices, and storage systems, all of which work under computer control. In the present work, analysis and modeling of a real problem has been considered for performance improvement. Modeling is done for analyzing the performance of an existing model, to propose a new layout for the system. Effect of factors like part mix, layout type, and batching condition, on the system performance in terms of productivity, system utilization rate, and cycle time is analyzed. The work includes simulation study along with Taguchi's experimental design framework for studying how different factors with varying levels affect system performance. ProModel software is used for simulating existing and proposed models of the manufacturing firm. Further, analysis of variance (ANOVA) is employed for finding the most important factor that affects system performance. Proposed methodology helps in determining best factor-level combination for each performance parameter. The results show that the system performs well with the implementation of loop layout having many numbers of batches. Towards the end, the scope of further is highlighted. [ABSTRACT FROM AUTHOR]

The first step of a geometrical and dimensional tolerance analysis is to determine kinematic loops that affect the functional requirements and the tolerances that influence the relative positioning between two topological elements of a part. This process is called the interpretation of geometric and dimensional tolerances. The second step is a solution procedure to verify if the functional requirements will be met with the current tolerances. This paper presents the implementation of a C++ library for the interpretation of geometric and dimensional tolerances in order to accomplish the first step of the tolerance analysis process. First, the data structures that allow storing the tolerances, the toleranced part data model, and the assembly graph model are introduced. This is followed by the description of the algorithms for retrieving the relevant kinematic loops from the assembly graph and the tolerances that affect the relative positioning between any two topological elements. Finally, an example demonstrates how to use the interpretation data obtained from the library to calculate and verify the functional requirements. [ABSTRACT FROM AUTHOR]

This paper reports the development of a fully automated method for the multianalyte determination of twenty pesticides belonging to different classes (triazines, phenylureas, organophosphates, anilines, acidic, propanil, and molinate) in natural and treated waters. The method, based on on-line solid-phase extraction–liquid chromatography–electrospray–tandem mass spectrometry, is highly sensitive (limits of detection between 0.004 and 2.8 ng L−1), precise (relative standard deviations between 2.0 and 12.1%), reliable (two selected reaction-monitoring transitions are monitored per compound), rapid (45 min per sample), and simple. The application of this method to the monitoring of the target compounds in a waterworks revealed the presence of the pesticides investigated at concentrations up to 516 and 82 ng L−1 (total pesticide concentration) in river water and ground water, respectively, used as sources, and their gradual removal through the purification process. [ABSTRACT FROM AUTHOR]