Boolean decomposition for AIG optimization

Restructuring techniques for And-Inverter Graphs (AIG), such as rewriting and refactoring, are powerful, scalable and fast, achieving highly optimized AIGs after few iterations. However, these techniques are biased by the original AIG structure and limited by single output optimizations. This paper investigates AIG optimization for area, exploring how far Boolean methods can reduce AIG nodes through local optimization.Boolean division is applied for multi-output functions using two-literal divisors and Boolean decomposition is introduced as a method for AIG optimization. Multi-output blocks are extracted from the AIG and optimized, achieving a further AIG node reduction of 7.76% on average for ITC99 and MCNC benchmarks.Peer ReviewedPostprint (author's final draft

Voltage noise analysis with ring oscillator clocks

Voltage noise is the main source of dynamic variability in integrated circuits and a major concern for the design of Power Delivery Networks (PDNs). Ring Oscillators Clocks (ROCs) have been proposed as an alternative to mitigate the negative effects of voltage noise as technology scales down and power density increases. However, their effectiveness highly depends on the design parameters of the PDN, power consumption patterns of the system and spatial locality of the ROCs within the clock domains. This paper analyzes the impact of the PDN parameters and ROC location on the robustness to voltage noise. The capability of reacting instantaneously to unpredictable voltage droops makes ROCs an attractive solution, which allows to reduce the amount of decoupling capacitance without downgrading performance. Tolerance to voltage noise and related benefits can be increased by using multiple ROCs and reducing the size of the clock domains. The analysis shows that up to 83% of the margins for voltage noise and up to 27% of the leakage power can be reduced by using local ROCs.Peer ReviewedPostprint (author's final draft

Pre-Supernova Alert System for Super-Kamiokande with Gadolinium

The current phase of the Super-Kamiokande experiment, SK-Gd, is characterized by the addition of gadolinium sulfate to the water Cherenkov detector, which improves the detection capability of thermal neutrons. For low energy events, the main detection channel for electron anti-neutrinos is the Inverse Beta Decay interaction, which has, in its final state, a positron and a neutron. The neutron thermal capture by gadolinium emits an 8 MeV gamma-ray cascade, improving the identification of the products of this process. This improved identification reduces the background for low energy events, allowing the analysis of neutrinos with en- ergies below the usual Super-Kamiokande thresholds. One possible detection by SK-Gd is the neutrinos coming from pre-Supernova stars, which correspond to the last evolutionary state of massive stars before core-collapse Supernova. During this stage, pair annihilation and beta decay processes are the main cooling mechanisms of the massive stars, emitting high fluxes of electron anti-neutrinos. Their detection could provide an early warning for core-collapse Supernovae. The techniques for the development of the pre-Supernova alert system for SK-Gd are presented in this thesis

Support-reducing decomposition for FPGA mapping

Decomposition is a technology-independent process, in which a large complex function is broken into smaller, less complex functions. The costs of two-level or factored-form representations (cubes and literals) are used in most decomposition methods, as they have a high correlation with the area of cell-based designs. However, this correlation is weaker for field-programmable gate arrays (FPGAs) based on look-up tables. Furthermore, local optimizations have limited power due to the structural bias of the circuit descriptions. This paper tries to reduce the structural biasing by remapping the LUT network and decomposing the derived functions using the support as cost function. The proposed method improves the FPGA mapping results of a commercial tool for the 20 largest MCNC benchmarks, with gains of 28% in delay plus 18% in area when targeting delay, and a reduction of 28% in area plus 14% in delay with area as cost function. Results with 23% less area and 6% less delay are obtained after physical synthesis (post place-and-route). Moreover, 12 of the best known results for delay (and 3 for area) of the EPFL benchmarks are improved.Peer ReviewedPostprint (author's final draft

Uma ponte entre a Teoria e a prática: PIBID História dna Era Vargas

Anais do XVII Congresso Internacional das Jornadas de Educaão História - teoria, pesquisa e prática - I Encontro da AIPEDH - Associação Iber-Americana de Pesquisadores em Educação História, realizado pela Universidade Federal da Integração Latino-Americana, entre 02, 03 e 04 de agosto de 2017.O PIBID História UNICENTRO-PR, busca ressignificar os parâmetros de ensino de História, no Colégio Estadual João XXIII, a partir de suas experiências, desenvolvendo problematizações e a criticidade dos alunos, afastando-se da História pautada em números e na reprodução de conteúdo, para aquela que faz seres conscientes da sua posição na sociedade enquanto agentes históricos, delineando o despertar da sua consciência histórica. O PIBID nos proporciona um laboratório experimental da profissão, como futuros docentes, sair do teórico oportunizado pela graduação, e vivenciar a profissão em sala de aula. Desenvolvemos no terceiro ano, do ensino médio, no Colégio Estadual João XXIII, uma dessas experiências. A partir da construção do conhecimento histórico, e a busca pelo saber. Arquitetou-se o debate, no qual os alunos problematizaram diversas características importantes da Era Vargas, apontando aspectos contra e a favor do governo, elaborando suas considerações, sobre tal momento político passado em nossa sociedade. Fazendo um vínculo com a atual política brasileir

On the well-posedness in Besov-Herz spaces for the inhomogeneous incompressible Euler equations

In this paper we study the inhomogeneous incompressible Euler equations in the whole space $\mathbb{R}^n$ with $n\geq3$. We obtain well-posedness and blow-up results in a new framework for inhomogeneous fluids, more precisely Besov-Herz spaces that are Besov spaces based on Herz ones, covering particularly critical cases of the regularity. Comparing with previous works on Besov spaces, our results provide a larger initial data class for a well-defined flow. For that, we need to obtain suitable linear estimates for some conservation-law models in our setting such as transport equations and the linearized inhomogeneous Euler system.Comment: 26 pages. We have included some further comments and remark

Nuclear modification factor in small system collisions within perturbative QCD including thermal effects

In this paper, the nuclear modification factors, RxA, are investigated for pion production in small system collisions, measured by PHENIX experiment at RHIC (Relativistic Heavy Ion Collider). The theoretical framework is the parton transverse momentum kT-factorization formalism for hard processes at small momentum fraction, x. Evidence for collective expansion and thermal effects for pions, produced at equilibrium, is studied based on phenomenological parametrization of blast-wave type in the relaxation time approximation. The dependencies on the centrality and on the projectile species are discussed in terms of the behavior of Cronin peak and the suppression of RxA at large transverse momentum, pT. The multiplicity of produced particles, which is sensitive to the soft sector of the spectra, is also included in the present analysis

Increasing the robustness of digital circuits with ring oscillator clocks

Technology scaling enables lower supply voltages, but also increases power density of integrated circuits. In this context, power integrity becomes a major concern in the implementation of highperformance designs. This paper analyzes the influence of Ring Oscillator Clocks (ROCs) on mitigating the impacts of voltage noise. A design with an ROC as the clock source is able to work correctly even in the presence of severe and unpredictable voltage emergencies, without degrading the average performance and power metrics of the circuit. ROCs offer an instantaneous and continuous adaptation to the environment conditions, thus reducing the margins used to prevent timing failures. ROCs provide robustness independently of the power delivery network, thus relaxing the constraints required for the design of the PCB and package. As a by-product, the inherent jitter generated by ROCs produces a spreadspectrum effect that reduces electromagnetic emissions.Peer ReviewedPostprint (published version

Local and global analysis in Besov-Morrey spaces for inhomogeneous Navier-Stokes equations

In this paper we consider the incompressible inhomogeneous Navier-Stokes equations in the whole space with dimension $n\geq 3$. We present local and global well-posedness results in a new framework for inhomogeneous fluids, namely Besov-Morrey spaces $\mathcal{N}_{p,q,r}^{s}$ that are Besov spaces based on Morrey ones. In comparison with the previous works in Sobolev and Besov spaces, our results provide a larger initial-data class for both the velocity and density, constructing a unique global-in-time flow under smallness conditions on weaker initial-data norms. In particular, we can consider some kind of initial discontinuous densities, since our density class $\mathcal{N}_{p,q,\infty }^{n/p}\cap L^{\infty }$ is not contained in any space of continuous functions. From a technical viewpoint, the Morrey underlying norms prevent the common use of energy-type and integration by parts arguments, and then we need to obtain some estimates for the localizations of the heat semigroup, the commutator, and the volume-preserving map in our setting, as well as estimates for transport equations and the linearized inhomogeneous Navier-Stokes system.Comment: 34 pages. We have improved some results and included some further words/phrases and remark