Heat fluctuations in Ising models coupled with two different heat baths

Monte Carlo simulations of Ising models coupled to heat baths at two different temperatures are used to study a fluctuation relation for the heat exchanged between the two thermostats in a time $\tau$. Different kinetics (single--spin--flip or spin--exchange Kawasaki dynamics), transition rates (Glauber or Metropolis), and couplings between the system and the thermostats have been considered. In every case the fluctuation relation is verified in the large $\tau$ limit, both in the disordered and in the low temperature phase. Finite-$\tau$ corrections are shown to obey a scaling behavior.Comment: 5 pages, 2 figures. To be published in Journal of Physics A: Mathematical and Theoretical as fast track communicatio

Energy and Heat Fluctuations in a Temperature Quench

Fluctuations of energy and heat are investigated during the relaxation following the instantaneous temperature quench of an extended system. Results are obtained analytically for the Gaussian model and for the large $N$ model quenched below the critical temperature $T_C$. The main finding is that fluctuations exceeding a critical threshold do condense. Though driven by a mechanism similar to that of Bose-Einstein condensation, this phenomenon is an out-of-equilibrium feature produced by the breaking of energy equipartition occurring in the transient regime. The dynamical nature of the transition is illustrated by phase diagrams extending in the time direction.Comment: To be published in the Proceedings of the Research Program "Small system non equilibrium fluctuations, dynamics and stochastics, and anomalous behavior", Kavli Institute for Theoretical Physics China, July 2013. 40 pages, 9 figure

A data analytics-based energy information system (EIS) tool to perform meter-level anomaly detection and diagnosis in buildings

Recently, the spread of smart metering infrastructures has enabled the easier collection of building-related data. It has been proven that a proper analysis of such data can bring significant benefits for the characterization of building performance and spotting valuable saving opportunities. More and more researchers worldwide are focused on the development of more robust frameworks of analysis capable of extracting from meter-level data useful information to enhance the process of energy management in buildings, for instance, by detecting inefficiencies or anomalous energy behavior during operation. This paper proposes an innovative anomaly detection and diagnosis (ADD) methodology to automatically detect at whole-building meter level anomalous energy consumption and then perform a diagnosis on the sub-loads responsible for anomalous patterns. The process consists of multiple steps combining data analytics techniques. A set of evolutionary classification trees is developed to discover frequent and infrequent aggregated energy patterns, properly transformed through an adaptive symbolic aggregate approximation (aSAX) process. Then a post-mining analysis based on association rule mining (ARM) is performed to discover the main sub-loads which mostly affect the anomaly detected at the whole-building level. The methodology is developed and tested on monitored data of a medium voltage/low voltage (MV/LV) transformation cabin of a university campus

Economias Sexuais, Amor E Tráfico De Pessoas – Novas Questões Conceituais

In this text I comment on recent discussions about sexual economies, human trafficking and the relationship between these problematics, considering new questions that are raised in the debate about them. I dialog with other articles published in this issue of the cadernos pagu, considering the results of studies conducted in Brazil and other Latin American countries. My comments focus on two issues that arose in the dialog between this work and the articles of Christian Groess Gren, Marcia Anita Sprandel, Kamala Kempadoo and Amalia Cabezas published in this volume. I first refer to the analytical possibilities and the limits of concepts such as sexual economies and sex markets. A second question relates to forms of governmentality articulated in the regimes for fighting human trafficking that affect these exchanges, particularly sexual work. The question is, in the fifteen years since the enactment of the Palermo Protocol, the most important supranational legal instrument related to this crime, what new issues appear in the analysis of these regimes and of their effects on sexual and economic exchanges?. © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.20164

Phase separation of binary fluids with dynamic temperature

Phase separation of binary fluids quenched by contact with cold external walls is considered. Navier-Stokes, convection-diffusion, and energy equations are solved by lattice Boltzmann method coupled with finite-difference schemes. At high viscosity, different morphologies are observed by varying the thermal diffusivity. In the range of thermal diffusivities with domains growing parallel to the walls, temperature and phase separation fronts propagate towards the inner of the system with power-law behavior. At low viscosity hydrodynamics favors rounded shapes, and complex patterns with different lengthscales appear. Off-symmetrical systems behave similarly but with more ordered configurations.Comment: Accepted for publication in Phys. Rev. E, 11 figures, best quality figures available on reques

Enhancing operational performance of AHUs through an advanced fault detection and diagnosis process based on temporal association and decision rules

The pervasive monitoring of HVAC systems through Building Energy Management Systems (BEMSs) is enabling the full exploitation of data-driven based methodologies for performing advanced energy management strategies. In this context, the implementation of Automated Fault Detection and Diagnosis (AFDD) based on collected operational data of Air Handling Units (AHUs) proved to be particularly effective to prevent anomalous running modes which can lead to significant energy waste over time and discomfort conditions in the built environment. The present work proposes a novel methodology for performing AFDD, based on both unsupervised and supervised data-driven methods tailored according to the operation of an AHU during transient and non-transient periods. The whole process is developed and tested on a sample of real data gathered from monitoring campaigns on two identical AHUs in the framework of the Research Project ASHRAE RP-1312. During the start-up period of operation, the methodology exploits Temporal Association Rules Mining (TARM) algorithm for an early detection of faults, while during non-transient period a number of classification models are developed for the identification of the deviation from the normal operation. The proposed methodology, conceived for quasi real-time implementation, proved to be capable of robustly and promptly identifying the presence of typical faults in AHUs

Online implementation of a soft actor-critic agent to enhance indoor temperature control and energy efficiency in buildings

Recently, a growing interest has been observed in HVAC control systems based on Artificial Intelligence, to improve comfort conditions while avoiding unnecessary energy consumption. In this work, a model-free algorithm belonging to the Deep Reinforcement Learning (DRL) class, Soft Actor-Critic, was implemented to control the supply water temperature to radiant terminal units of a heating system serving an office building. The controller was trained online, and a preliminary sensitivity analysis on hyperparameters was performed to assess their influence on the agent performance. The DRL agent with the best performance was compared to a rule-based controller assumed as a baseline during a three-month heating season. The DRL controller outperformed the baseline after two weeks of deployment, with an overall performance improvement related to control of indoor temperature conditions. Moreover, the adaptability of the DRL agent was tested for various control scenarios, simulating changes of external weather conditions, indoor temperature setpoint, building envelope features and occupancy patterns. The agent dynamically deployed, despite a slight increase in energy consumption, led to an improvement of indoor temperature control, reducing the cumulative sum of temperature violations on average for all scenarios by 75% and 48% compared to the baseline and statically deployed agent respectively

Late Quaternary activity along the Scorciabuoi Fault (Southern Italy) as inferred from electrical resistivity tomographies

The Scorciabuoi Fault is one of the major tectonic structures affecting the Southern Apennines, Italy. Across its central sector, we performed several electrical resistivity tomographies with different electrode spacing (5 and 10 m) and using a multielectrode system with 32 electrodes. All tomographies were acquired with two different arrays, the dipole-dipole and the Wenner-Schlumberger. We also tested the different sensitivity of the two arrays with respect to the specific geological conditions and research goals. Detailed geological mapping and two boreholes were used to calibrate the electrical stratigraphy. In all but one tomography (purposely performed off the fault trace), we could recognise an abrupt subvertical lateral variation of the main sedimentary bodies showing the displacement and sharp thickening of the two youngest alluvial bodies in the hanging-wall block. These features are interpreted as evidence of synsedimentary activity of the Scorciabuoi Fault during Late Pleistocene and possibly as recently as Holocene and allow accurate location of the fault trace within the Sauro alluvial plain

Trichoderma harzianum cerato-platanin enhances hydrolysis of lignocellulosic materials

Considering its worldwide abundance, cellulose can be a suitable candidate to replace the fossil oil-based materials, even if its potential is still untapped, due to some scientific and technical gaps. This work offers new possibilities demonstrating for the first time the ability of a cerato-platanin, a small fungal protein, to valorize lignocellulosic Agri-food Wastes. Indeed, cerato-platanins can loosen cellulose rendering it more accessible to hydrolytic attack. The cerato-platanin ThCP from a marine strain of Trichoderma harzianum, characterized as an efficient biosurfactant protein, has proven able to efficiently pre-treat apple pomace, obtaining a sugar conversion yield of 65%. Moreover, when used in combination with a laccase enzyme, a notable increase in the sugar conversion yield was measured. Similar results were also obtained when other wastes, coffee silverskin and potato peel, were pre-treated. With respect to the widespread laccase pre-treatments, this new pre-treatment approach minimizes process time, increasing energy efficiency