Resumo O artigo apresenta novas abordagens para investigar o passado usando tecnologias digitais. O projeto “Pauliceia 2.0: mapeamento colaborativo da história de São Paulo (1870-1920)” é de código aberto e visa engajar o público de maneira ampla, usando metodologias colaborativas. O texto discute a concepção do projeto, seu estágio atual e suas perspectivas. Além disso, também se oferece o Pauliceia 2.0 como um estudo de caso para discutir a relação entre tecnologias digitais e métodos históricos. O resultado desse percurso, ao menos essa é a intenção dos autores listados e dos demais integrantes da equipe do projeto, nomeados ao final do artigo, almeja ressignificar o trabalho em questão na confluência entre humanidades digitais, história pública e ciência aberta.

Abstract This article presents new approaches for investigating the past using digital technologies. “Pauliceia 2.0: collaborative mapping of the history of São Paulo (1870-1920)” is an open-source project intended to broadly engage with the public through collaborative methodologies. This text discusses the concept, current status, and prospects of this project, and presents it as a case study to discuss the relationship between digital technologies and historical methods. The product of this journey (at least the outcome intended by the authors and the other team members listed at the end of the article) is meant to assign new meaning to the project at the juncture between digital humanities, public history, and open science.

ABSTRACT Time metrics are extremely important to evaluate the transmission performance on Wireless Mesh Networks (WMNs), whose main characteristic is to use multihop technology to extend the network coverage area. One of such metrics is WCETT (Weighted Cumulative Expected Transmission Time), in which transmission times per hop are weighted for both proactive and reactive conditions. Furthermore, such metrics are able to detect delays that can degrade some network services. This paper presents an optimization model to minimize WCETT in a WMN, subject to constraints grouped by bandwidth, flow control and power control. As the model includes nonlinear constraints, we propose a heuristic to solve it, which divides the problem in two subproblems. The first subproblem maximizes the network link capacity and a Simulated Annealing algorithm is used to solve it. Considering the link capacities obtained, the second subproblem minimizes the WCETTs, which is formulated as a linear programming model. Some numerical results are presented, based on instances of WMNs randomly generated. Some of these results are compared with the results obtained by a commercial simulator in order to verify the coherence of the proposed heuristic for realistic scenarios.

Statecharts representam graficamente sistemas reativos que respondem aos estímulos externos ou internos e mudam estados de um dado sistema. Statecharts estendem diagramas de estado com hierarquia, paralelismo e interdependência. Devido às suas características, eles foram adaptados para representar e tratar analiticamente modelos de desempenho (sistemas reativos cujo desempenho deve ser avaliado). Uma característica presente em Statecharts é registrar (ou memorizar) um estado do sistema que não é possível representar numa forma direta em modelos Markovianos devido à sua propriedade de "sem memória". São duas as contribuições deste artigo: mostrar que Statecharts são viáveis para especificar sistemas reativos e avaliar o seu desempenho tanto por técnicas analíticas quanto por simulação; mostrar que a inclusão de representação de memória em Statecharts pode, de fato, ser tratada por abordagens analíticas e de simulação. Um estudo de caso de um sistema de manufatura é considerado para mostrar que os objetivos foram alcançados.

Statecharts are a graphical representation to model reactive systems that respond to external or internal stimuli by changing the state of a given system. Statecharts can be seen as an extension of state-transition diagrams that allows modeling hierarchy, orthogonality, and interdependence. Due to their features to represent reactive systems, Statecharts have been adapted to represent and deal analytically with performance models (reactive systems whose performance is to be evaluated). An interesting feature present in Statecharts is to record the system's state, which cannot be represented in Markov models in a straightforward manner due to its "memory-less" property. The contributions of this paper are: show that Statecharts are a feasible alternative to specify a reactive system so that its performance can be evaluated by both analytical and simulation techniques; show that the inclusion of the memory representation in the Statecharts specification can indeed be made by both analytical and simulation techniques. The results of a case study of a manufacturing system show that the objectives are achieved.

This paper describes an innovative technique, the gradient pattern analysis (GPA), for analysing spatially extended dynamics. The measures obtained from GPA are based on the spatio-temporal correlations between large and small amplitude fluctuations of the structure represented as a dynamical gradient pattern. By means of four gradient moments it is possible to quantify the relative fluctuations and scaling coherence at a dynamical numerical lattice and this is a set of proper measures of the pattern complexity and equilibrium. The GPA technique is applied for the first time in 3D-simulated molecular chains with the objective of characterizing small symmetry breaking, amplitude and phase disorder due to spatio-temporal fluctuations driven by the spatially extended dynamics of a relaxation regime.