Analysis of source term aspects in the experiment Phebus FPT1 with the MELCOR and CFX codes

Several aspects related to the source term in the Phebus FPT1 experiment have been analyzed with the help of MELCOR 1.8.5 and CFX 5.7 codes. Integral aspects covering circuit thermalhydraulics, fission product and structural material release, vapours and aerosol retention in the circuit and containment were studied with MELCOR, and the strong and weak points after comparison to experimental results are stated. Then, sensitivity calculations dealing with chemical speciation upon release, vertical line aerosol deposition and steam generator aerosol deposition were performed. Finally, detailed calculations concerning aerosol deposition in the steam generator tube are presented. They were obtained by means of an in-house code application, named COCOA, as well as with CFX computational fluid dynamics code, in which several models for aerosol deposition were implemented and tested, while the models themselves are discussed.     

Understanding the Role of Body Movement in Player Engagement

The introduction of full-body controllers has made computer games more accessible and promises to provide a more natural and engaging experience to players. However, the relationship between body movement and game engagement is not yet well understood. In this article, I consider how body movement affects the player's experience during game play. I start by presenting a taxonomy of body movements observed during game play. These are framed in the context of a body of previously published research that is then embedded into a novel model of engagement. This model describes the relationship between the taxonomy of movement and the type of engagement that each class of movement facilitates. I discuss the factors that may inhibit or enhance such relationship. Finally, I conclude by considering how the proposed model could lead to a more systematic and effective use of body movement for enhancing game experience.     

Congestion-aware ant colony based routing algorithms for efficient application execution on Network-on-Chip platform

Networks-on-Chip (NoC) is an interesting option in design of communication infrastructures for embedded systems. It provides a scalable structure and balanced communication between the cores. Parallel applications that take advantage of the NoC architectures, are usually are communication-intensive. Thus, a big deal of data packets is transmitted simultaneously through the network. In order to avoid congestion delays that deteriorate the execution time of the implemented applications, an efficient routing strategy must be thought of carefully. In this paper, the ant colony optimization paradigm is explored to find and optimize routes in a mesh-based NoC. The proposed routing algorithms are simple yet efficient. The routing optimization is driven by the minimization of total latency during packets transmission between the tasks that compose the application. The presented performance evaluation is threefold: first, the impact of well-known synthetic traffic patterns is assessed; second, randomly generated applications are mapped into the NoC infrastructure and some synthetic communication traffics, that follow known patterns, are used to simulate real situations; third, sixteen real-world applications of the E3S and one specific application for digital image processing are mapped and their execution time evaluated. In both cases, the obtained results are compared to those obtained with known general purpose algorithms for deadlock free routing. The comparison avers the effectiveness and superiority of the ant colony inspired routing.     

Observation of an Isokinetic Temperature and Compensation Effect for High-Temperature Crude Oil Fouling

The initial fouling rates of four crude oils were determined at a nominal bulk temperature of 315°C, an initial heated wall shear stress of 13 Pa, and initial surface temperatures between 375 and 445°C. These initial fouling rates ranged from 1.3(10^{? 6}) to 7.8(10^{? 5}) m² K/kJ. Corresponding Arrhenius plots were linear with the initial fouling rates passing through an isokinetic temperature of 407.5°C. A plot of the natural logarithm of the pre-exponential factors [7.6(10⁴)–5.2(10¹⁵) m² K/kJ] versus the apparent activation energies (128–269 kJ/mol) was also linear, confirming the validity of the isokinetic temperature and the presence of the compensation effect. Below the isokinetic temperature, the relative fouling rates were Crude Oil C > Crude Oil A > Crude Oil D > Crude Oil B; above the isokinetic temperature, the relative fouling rates were reversed (Crude Oil B > Crude Oil D > Crude Oil A > Crude Oil C). Chemical characterization of a fouling deposit suggested that the dominant fouling mechanism at these conditions was coking, with significant contributions from sedimentation (iron sulfide) and corrosion (～ 340 μ m/yr) of the 304 stainless steel test material.     

Valorization of Beef Tallow by Lipase-Catalyzed Interesterification with High Oleic Sunflower Oil

Although beef tallow (BT) has been considered a hard low-trans fat convenient to be used in several bakery applications, it has some undesirable characteristics like fatty acid composition, crystallization behavior, graininess formation and poor plastic range. This work studied the modification of BT by blending at different percentages with high oleic sunflower oil (HOSFO) followed by the enzyme-catalyzed interesterification of the blends. The reduction in the solid fat content achieved by the simple blending was enhanced by the interesterification process, as a result of the increase in the concentration of the diunsaturated monosaturated type triacylglycerols. Interesterification strongly impacted too on the crystallization behavior of the blends, since products showed more homogeneous and regular crystals than the starting mixture. Results show that lipase catalyzed interesterification of BT with HOSFO offers a useful tool for the design of fats with adjustable physicochemical properties, improved with respect to that of the starting fats.     

Prediction of Buckling-Mode Interaction in Composite Columns

Pultruded structural shapes are often used as columns of intermediate length, for which the global and local buckling loads are close. Interaction between the two buckling modes is accounted for in design by an empirical interaction constant. Theoretical/numerical prediction of such a constant is presented in this article. Stability theory is used to demonstrate the existence of buckling-mode interaction. The continuation method is used to study the imperfection sensitivity of the columns. A relationship between column imperfection and the interaction constant is established. Experimental results are presented to support the analysis.     

Structure identification of Boolean relations and plain bases for co-clones

We give a quadratic algorithm for the following structure identification problem: given a Boolean relation R and a finite set S of Boolean relations, can the relation R be expressed as a conjunctive query over the relations in the set S? Our algorithm is derived by first introducing the concept of a plain basis for a co-clone and then identifying natural plain bases for every co-clone in Post's lattice. In the process, we also give a quadratic algorithm for the problem of finding the smallest co-clone containing a Boolean relation.