Message passing and Monte Carlo algorithms: connecting fixed points with metastable states

Mean field-like approximations (including naive mean field, Bethe and Kikuchi and more general Cluster Variational Methods) are known to stabilize ordered phases at temperatures higher than the thermodynamical transition. For example, in the Edwards-Anderson model in 2-dimensions these approximations predict a spin glass transition at finite $T$. Here we show that the spin glass solutions of the Cluster Variational Method (CVM) at plaquette level do describe well actual metastable states of the system. Moreover, we prove that these states can be used to predict non trivial statistical quantities, like the distribution of the overlap between two replicas. Our results support the idea that message passing algorithms can be helpful to accelerate Monte Carlo simulations in finite dimensional systems.Comment: 6 pages, 6 figure

Las maravillas ocultas en la tabla periódica

Este trabajo constituye un enfoque holista de la Tabla Periódica (TP). Basados en el origen de los nombres de los elementos como punto de partida, es posible recorrer distintos campos del conocimiento, no sólo química, sino historia, geografía, mitología, biografías de personajes famosos, etc. Así, a medida que se aprende sobre los elementos químicos, su comportamiento y sus propiedades, se tiene la oportunidad de aprender y repasar sobre otras disciplinas. Es como si la (TP), a través de cada casilla, abriera una puerta hacia el maravilloso mundo del saber. La aplicación de esta propuesta en un curso electivo en la Universidad del Valle (Cali, Colombia) usando la TP como eje central ha permitido identificar nuevos caminos para enseñar química y caracterizar los aspectos que aumentan las competencias transversales de los alumnos de diversas carreras en la Universidad

Ultrasonic Fatigue Analysis on Steel Specimen with Temperature Control : Evaluation of Variable Temperature Effect

Non peer reviewe

Generalized L\"uscher Formula in Multi-channel Baryon-Meson Scattering

L\"uscher's formula relates the elastic scattering phase shifts to the two-particle energy levels in a finite cubic box. The original formula was obtained for elastic scattering of two massive spinless particles in the center of mass frame. In this paper, we consider the case for the scattering of a spin 1/2 particle with a spinless particle in multi-channel scattering. A generalized relation between the energy of two particle system and the scattering matrix elements is established. We first obtain this relation using quantum-mechanics in both center-of-mass frame and in a general moving frame. The result is then generalized to quantum field theory using methods outlined in Ref. \cite{Hansen:2012tf}. We verify that the results obtained using both methods are equivalent up to terms that are exponentially suppressed in the box size.Comment: One reference adde

Glauber Critical Dynamics: Exact Solution of the Kinetic Gaussian Model

In this paper, we have exactly solved Glauber critical dynamics of the Gaussian model on three dimensions. Of course, it is much easy to apply to low dimensional case. The key steps are that we generalize the spin change mechanism from Glauber's single-spin flipping to single-spin transition and give a normalized version of the transition probability . We have also investigated the dynamical critical exponent and found surprisingly that the dynamical critical exponent is highly universal which refer to that for one- two- and three-dimensions they have same value independent of spatial dimensionality in contrast to static (equilibrium) critical exponents.Comment: 9 page

Qualidade da carne de ovinos puros e cruzados criados no Semiárido Nordestino brasileiro.

Resumo: A procura por carne de qualidade tem proporcionado ao setor de ovinocultura a adoção por técnicas de produção que possam contribuir para disponibilizar ao mercado produtos que atendam as necessidades dos consumidores, que se tornam cada vez mais exigentes quanto à aquisição de produtos que possam trazer benefícios a saúde. Assim, objetivou-se determinar a qualidade da carne de ovinos puros e cruzados criados no semiárido Nordestino. Utilizaram-se 30 cordeiros machos e fêmeas, oriundos dos cruzamentos Morada Nova x Morada Nova, Rabo Largo x Morada Nova e Santa Inês x Morada Nova, alojados em baias e alimentados com dieta a base de capim Canarana, milho farelo de soja e calcário. Os animais foram abatidos com peso médio de 24 kg de peso vivo e as carcaças mantidas em câmara frigorífica a 4?C, por 24 horas. Após esse período, foi seccionado o músculo Longissimus dorsi que foi embalado, identificado e armazenado a 20 oC. Foram determinados os atributos físicos de capacidade de retenção de água, perda de peso por cocção e força de cisalhamento; os atributos químicos como umidade, proteína, cinza, lipídios e colesterol; avaliações subjetivas da carcaça como cor, marmoreio, textura da carne, distribuição da gordura, espessura da gordura e área de olho de lombo; os sensoriais de dureza, suculência, sabor, aroma e aceitação global e o perfil de ácidos graxos. O delineamento utilizado foi em esquema fatorial 3x2 (três grupos genéticos e dois sexos) e as médias comparadas pelo teste de Duncan a 5%. Não houve diferença (p>0,05) entre os genótipos para a composição química da carne, exceto para a variável lipídio (p0,05) dos genótipos avaliados. Os genótipos influenciaram (p 0.05) between genotypes for the chemical composition of meat, except for the lipid variable (p 0.05) of the evaluated genotypes. The genotypes influenced (p <0.05) in the concentrations of saturated fatty acids, monounsaturated and polyunsaturated as well as in the relations Ômega 3: Ômega : 6. and AGM:AGS. The gender factor influenced (P <0.05) in the variables moisture, shear strength, hardness, desirable fatty acids and relation Ômega 3: Õmega : 6. The cross between native breeds showed up with potential for quality meat production, the Morada Nova improved the physical and chemical attributes of the flesh and in their lipid profiles and sex factor improved softness attribute highlighting the meat of females.Dissertação (Mestrado em Zootecnia) - Universidade Estadual Vale do Acaraú, Sobral. Orientador: Aline Vieira Landim; Coorientadora: Lisiane Dorneles Lima

Imagens e a regulação da comoção: vulnerabilidade e testemunho

The aim of this work is to reflect on the compassionate appeal, political power and testimonial dimension of the photographs of the Syrian boy Aylan Kurdi, made by the Turkish photographer Nilüfer Demir in September of 2015, in the beach of Ali Hoca, in Bodrum, Turkey. At first, these photographs are distinguished in the wake of the so-called “trauma images”, or hyperimagens. Next, we argue that these images seems marked by the ostensible and expressive presence of children as suffering subjects in the visual construction of compassionate appeals. It is argued, then, about the capacity that images of the Syrian boy have to communicate the precariousness of certain lives. Finally, we analyze the photograph in light of the political potential of the witnessing and the very meaning of photography as rest.Keywords: Image. Affection. Vulnerability. Witnessing.O objetivo deste trabalho é refletir sobre o apelo compassivo, a força política e a dimensão testemunhal das fotografias do menino sírio Aylan Kurdi, feitas pela fotógrafa turca Nilüfer Demir em setembro de 2015, na praia de Ali Hoca, em Bodrum, na Turquia. Num primeiro momento, distingue-se essas fotografias na esteira das chamadas “imagens do trauma”, ou hiperimagens. Em seguida, destaca-se uma espécie de tópica em torno da qual algumas dessas imagens parecem se reunir, a saber, a presença ostensiva e expressiva de crianças como sujeitos sofredores na construção visual dos apelos compassivos. Argumenta-se, então, sobre a capacidade que imagens como as do menino sírio têm para comunicar a precariedade de certas vidas. Por fim, analisamos a fotografia à luz do potencial político do testemunho e do próprio significado da fotografia enquanto resto.Palavras-chave: Imagem. Comoção. Vulnerabilidade. Testemunho

Understanding motivational factors in choosing a mobility destination: the case of Kauno Kolegija

With the central question being why mobility students choose Kauno Kolegija, it is the main goal to find out their opinion about the school starting with the question, what was their motivation to study in Kauno Kolegija. 53 students participated in the survey, being the majority of them Erasmus students.The data were obtained by a survey that took the form of an online questionnaire. This survey includes answers from EU and Non-EU students and it is based on a quantitative survey, which is after studied using the graphical analysis program SPSS.The major objective of this research is to help Kauno Kolegija with the best information and results to provide the responsible people with enough material to improve and increase the incoming students flow into the school from mobility studies and internships.Since the Erasmus program started, the flow of students has been going up and down, having students from Turkey as 40% of the income, Kauno Kolegija will benefit with the results by understanding why East Europe and nearby countries has more incoming students than West Europe and be able to fight this unbalance.info:eu-repo/semantics/publishedVersio

Replica Cluster Variational Method

We present a general formalism to make the Replica-Symmetric and Replica-Symmetry-Breaking ansatz in the context of Kikuchi's Cluster Variational Method (CVM). Using replicas and the message-passing formulation of CVM we obtain a variational expression of the replicated free energy of a system with quenched disorder, both averaged and on a single sample, and make the hierarchical ansatz using functionals of functions of fields to represent the messages. We begin to study the method considering the plaquette approximation to the averaged free energy of the Edwards-Anderson model in the paramagnetic Replica-Symmetric phase. In two dimensions we find that the spurious spin-glass phase transition of the Bethe approximation disappears and the paramagnetic phase is stable down to zero temperature in all the three regular 2D lattices. The quantitative estimates of the free energy and of various other quantities improve those of the Bethe approximation. We provide the physical interpretation of the beliefs in the replica-symmetric phase as disorder distributions of the local Hamiltonians. The messages instead do not admit such an interpretation and indeed they cannot be represented as populations in the spin-glass phase at variance with the Bethe approximation.Comment: 32 pages, 14 figures. In the revised version the content has been reorganized in order to imporve readabilit