Isoscaling and the high Temperature limit

This study shows that isoscaling, usually studied in nuclear reactions, is a phenomenon common to all cases of fair sampling. Exact expressions for the yield ratio $R_{21}$ and approximate expressions for the isoscaling parameters $\alpha$ and $\beta$ are obtained and compared to experimental results. It is concluded that nuclear isoscaling is bound to contain a component due to sampling and, thus, a words of caution is issued to those interested in extracting information about the nuclear equation of state from isoscaling.Comment: 7 pages, 1 figur

Control Properties and Thermodynamic Analysis of Two Alternatives to Thermally Coupled Distillation Systems with Side Columns

The thermally coupled distillation configurations have received considerable attention because of their efficiency to reduce the energy required for the separation of ternary mixtures. The structure of the complex systems offers some control challenges arising from the transfer of vapor (or liquid) streams between the columns. Recently, some alternate schemes to thermally coupled distillation arrangements, that might provide better operational properties than the complex columns, have been proposed. In this work, we analyze the control properties of two alternative distillation schemes to the coupled systems. The theoretical control properties are analyzed with the application of the singular value decomposition technique. The results indicate that a reduction in the number of interconnections of the alternate configurations does not necessarily provide an improvement of its controllability properties. Also, second law calculations and energy consumptions were performed for the two alternate distillations schemes

Safer parameters for the Chor–Rivest cryptosystem

AbstractVaudenay’s cryptanalysis against Chor–Rivest cryptosystem is applicable when the parameters, p and h, originally proposed by the authors are used. Nevertheless, if p and h are both prime integers, then Vaudenay’s attack is not applicable. In this work, a choice of these parameters resistant to the existing cryptanalytic attacks, is presented. The parameters are determined in a suitable range guaranteeing its security and the computational feasibility of implementation. Regrettably, the obtained parameters are scarce in practice

Usos de Lengua Materna (L1) y Lengua Meta (L2) en un Contexto de Inmersión Real

Indiana University-Purdue University Indianapolis (IUPUI)The study of L1 and L2 uses by graduate students in a genuine immersion context or study abroad has not been widely explored. This study is an attempt to provide new insights from the perspective of the interactional and sociocultural sociolinguistics while maintaining constant links with studies in Second Language Acquisition and study abroad. The data collection stage of this study took place at the Universidad de Salamanca in Spain during the summer of 2005. For data collection, the researcher used participant observation. Students also completed a questionnaire about their uses of L1 and L2 while in their home country and during their stay in Spain, one at the beginning and another by the end of their studies in Salamanca. Results first concluded that the uses of L1 seem to be linked to the students’ own effort to carry out their class work or to learn more about the language or the topic they are working on in class, without being directly related with their instructor’s primary objective. Similar uses have been reported by Antón & DiCamilla (1999), Alley (2005), Brooks & Donato (1994), and Centeno-Cortés & Jiménez (2004). Secondly, perceived uses of L2 in the classroom were mostly related with those reported by Tarone & Swain (1995), that is, students used L2 for academic purposes. Thirdly, the L1-L2 switching supported by the findings of Liebscher y Dailey-O’Cain (2005) seems to indicate that students perceive themselves as a bilingual speech community and take it for granted that their interlocutor is proficient in both languages. Finally, the study suggests some pathway for future research including the reasons for the poor L2 use by students whose supposed proficiency level is advanced as reported in the study. Additionally, some pedagogical implications are provided

Advanced titanium scaffolds obtained by directional freeze-drying: on the influence of processing conditions

Ministry of Science and Innovation of Spain under Grant No. MAT2010-20855Junta de Andalucía (Spain) / FEDER (EU), through the project Ref. P12-TEP-140