Superfluid phases of 3^3He in a periodic confined geometry

Predictions and discoveries of new phases of superfluid $^3$He in confined geometries, as well as novel topological excitations confined to surfaces and edges of near a bounding surface of $^3$He, are driving the fields of superfluid $^3$He infused into porous media, as well as the fabrication of sub-micron to nano-scale devices for controlled studies of quantum fluids. In this report we consider superfluid $^3$He confined in a periodic geometry, specifically a two-dimensional lattice of square, sub-micron-scale boundaries ("posts") with translational invariance in the third dimension. The equilibrium phase(s) are inhomogeneous and depend on the microscopic boundary conditions imposed by a periodic array of posts. We present results for the order parameter and phase diagram based on strong pair breaking at the boundaries. The ordered phases are obtained by numerically minimizing the Ginzburg-Landau free energy functional. We report results for the weak-coupling limit, appropriate at ambient pressure, as a function of temperature T, lattice spacing L, and post edge dimension, $d$. For all $d$ in which a superfluid transition occurs, we find a transition from the normal state to a periodic, inhomogeneous "polar" phase with $T_{c_1} < T_c$ for bulk superfluid $^3$He. For fixed lattice spacing, L, there is a critical post dimension, d_c, above which only the periodic polar phase is stable. For $d < d_c$ we find a second, low-temperature phase onsetting at $T_{c_2} < T_{c_1}$ from the polar phase to a periodic "B-like" phase. The low temperature phase is inhomogeneous, anisotropic and preserves time-reversal symmetry, but unlike the bulk B-phase has only $D_{4h}$ point symmetry.Comment: 14 pages, 4 figures. Journal of Low Temperature Physics (2013

A comparison of metaheuristics algorithms for combinatorial optimization problems. application to phase balancing in electric distribution systems

Metaheuristics Algorithms are widely recognized as one of most practical approaches for Combinatorial Optimization Problems. This paper presents a comparison between two metaheuristics to solve a problem of Phase Balancing in Low Voltage Electric Distribution Systems. Among the most representative mono-objective metaheuristics, was selected Simulated Annealing, to compare with a different metaheuristic approach: Evolutionary Particle Swarm Optimization. In this work, both of them are extended to fuzzy domain to modeling a multiobjective optimization, by mean of a fuzzy fitness function. A simulation on a real system is presented, and advantages of Swarm approach are evidenced.Fil: Schweickardt, Gustavo Alejandro. Fundacion Bariloche. Instituto de Economia Energetica; Argentina. Comision Nacional de Energia Atomica. Gerencia del Area de Investigaciones y Aplicaciones no Nucleares. Gerencia de Fisica (CAB); ArgentinaFil: Miranda, V.. Universidad de Porto; PortugalFil: Wiman, G.. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentin

The extended mapping class group is generated by three symmetries

We prove that the extended mapping class group is generated by three orientation reversing involutions.Comment: A version of the article which appeared in C. R. Acad. Sc

Forest-edge effects on sea-salt aerosol deposition : a wind-tunnel study using living oak leaves

Landscape patchiness creates aerodynamic transition zones that affect the exchange of nutrients and pollutants between the atmosphere and vegetation. Using an artificially-generated NaCl aerosol (mass-versus-particle-size distribution with aerodynamic mean particle diameter 1.6 mu m; geometric standard deviation 1.9), we investigated the forest-edge effect on aerosol deposition within a model oak (Quercus robur) canopy in a wind tunnel with an emulated beach-to-forest transition. The deposition rate around the forest edge was 2-3 times higher than to the beach and 50%-60% higher than to the interior of the forest. The deposition velocity at the edge was 0.06 cm s(-1), which is 2-3 times higher than the beach-deposition velocity. Our results can help improve estimates of aerosol-borne inputs of nutrients or pollutants to forested landscapes that experience shifts in meteorological regimes due to changes in climate and forestry practices, in particular with respect to deciduous species in coastal environments

An Alternative Method for Solving a Certain Class of Fractional Kinetic Equations

An alternative method for solving the fractional kinetic equations solved earlier by Haubold and Mathai (2000) and Saxena et al. (2002, 2004a, 2004b) is recently given by Saxena and Kalla (2007). This method can also be applied in solving more general fractional kinetic equations than the ones solved by the aforesaid authors. In view of the usefulness and importance of the kinetic equation in certain physical problems governing reaction-diffusion in complex systems and anomalous diffusion, the authors present an alternative simple method for deriving the solution of the generalized forms of the fractional kinetic equations solved by the aforesaid authors and Nonnenmacher and Metzler (1995). The method depends on the use of the Riemann-Liouville fractional calculus operators. It has been shown by the application of Riemann-Liouville fractional integral operator and its interesting properties, that the solution of the given fractional kinetic equation can be obtained in a straight-forward manner. This method does not make use of the Laplace transform.Comment: 7 pages, LaTe

Making mentoring work: The need for rewiring epistemology

To help produce expert coaches at both participation and performance levels, a number of governing bodies have established coach mentoring systems. In light of the limited literature on coach mentoring, as well as the risks of superficial treatment by coach education systems, this paper therefore critically discusses the role of the mentor in coach development, the nature of the mentor-mentee relationship and, most specifically, how expertise in the mentee may best be developed. If mentors are to be effective in developing expert coaches then we consequently argue that a focus on personal epistemology is required. On this basis, we present a framework that conceptualizes mentee development on this level through a step by step progression, rather than unrealistic and unachievable leap toward expertise. Finally, we consider the resulting implications for practice and research with respect to one-on-one mentoring, communities of practice, and formal coach education

Interaksi Sosial Komunitas Wibu Harajuku Nation (HANA) Purwokerto

Artikel ini membahas interaksi sosial yang terjadi pada wibu di dalam komunitas Harajuku Nation Purwokerto. Interaksi sosial merupakan kebutuhan mendasar setiap manusia sebagai makhluk sosial. Selama ini masih terdapat asumsi negatif dari masyarakat mengenai wibu yaitu seseorang yang nolep, ansos, dan tidak dapat berbaur dengan lingkungan. Padahal interaksi sosial menjadi sebuah kunci seluruh kehidupan sosial, karena pada dasarnya manusia adalah makhluk hidup yang membutuhkan satu dengan lainnya. Sehingga manusia tidak dapat hidup sendiri. Kemudian terbentuklah sebuah komunitas yang dapat menjadi menampung mereka dan berisi orang-orang yang menyukai budaya populer Jepang. Penelitian ini menggunakan metode kualitatif deskriptif. Teknik analisis datanya menggunakan model dari Miles dan Huberman (1992) yang meliputi tiga langkah yaitu reduksi data, penyajian data, dan verifikasi data/ kesimpulan. Hasil dari penelitian ini menunjukkan bahwa terdapat interaksi sosial yang dilakukan anggota komunitas Harajuku Nation yang terbagi menjadi dua yaitu interaksi di dalam komunitas dan interaksi di luar komunitas. Hal tersebut menunjukkan bahwa asumsi negatif mengenai wibu tidak sepenuhnya benar, karena pada kenyataannya mereka dapat melakukan interaksi sosial di dalam komunitas maupun di luar komunitas dengan baik. Kata Kunci: Interaksi Sosial, Wibu, Komunitas &nbsp; This article discusses the social interactions that occur in wibu in the Harajuku Nation Purwokerto community. Social interaction is a fundamental need of every human being as a social being. There are still negative assumptions from society about wibu, namely someone who is nolep, ansos, and cannot blend in with the environment. Whereas social interaction is a key to all social life, because basically humans are living things that need one another. So humans cannot live alone. Then a community was formed that can accommodate them and contains people who like Japanese popular culture. This research uses descriptive qualitative methods. The data analysis technique uses a model from Miles and Huberman (1992) which includes three steps, namely data reduction, data presentation, and data verification/conclusion. The results of this study show that there are social interactions carried out by members of the Harajuku Nation community which are divided into two, namely interactions within the community and interactions outside the community. This shows that the negative assumptions about wibu are not entirely true, because in reality they can carry out social interactions within the community and outside the community well. Keywords: Social Interaction, Wibu, Communit