Stigmergy-based modeling to discover urban activity patterns from positioning data

Positioning data offer a remarkable source of information to analyze crowds urban dynamics. However, discovering urban activity patterns from the emergent behavior of crowds involves complex system modeling. An alternative approach is to adopt computational techniques belonging to the emergent paradigm, which enables self-organization of data and allows adaptive analysis. Specifically, our approach is based on stigmergy. By using stigmergy each sample position is associated with a digital pheromone deposit, which progressively evaporates and aggregates with other deposits according to their spatiotemporal proximity. Based on this principle, we exploit positioning data to identify high density areas (hotspots) and characterize their activity over time. This characterization allows the comparison of dynamics occurring in different days, providing a similarity measure exploitable by clustering techniques. Thus, we cluster days according to their activity behavior, discovering unexpected urban activity patterns. As a case study, we analyze taxi traces in New York City during 2015

Stigmergic behaviour and nodal places in residential areas: Case of post-socialist city Kharkiv in Ukraine

The study of urban development and regeneration of residential areas in the cities are mainly focused on the separate infrastructural systems and less how networks of infrastructural systems and their elements, as nodal places, interact with the existing living environment and its urban tissue. The central goal of the paper is to examine contemporary residential areas of low liveability with nodal places of logistics and services infrastructural networks, with an eye on existing urban policies and application of transdisciplinary concept of stigmergy in contemporary urban environment. Research objectives: (a) conceptualisation of stigmergic process in urban planning; (b) overview of socialist and post-socialist urban policies for residential areas; (c) stigmergic behaviour in the development of nodal places in residential areas. Methodology: Use of Earth Time Observation Systems for identification of urban changes of nodal places under the stigmergic behaviour in the case study residential area in post-socialist city in Ukraine; contextualization of the case study with the categories: Ideology, Institutional level, Politics, Economics, Mobile Infrastructures. Discussion and conclusion: (a) as concept, stigmergic behaviours are efficient, but work as a self-organization form; (b) urban policies should, under the stigmergic behaviours, contextualize changes, continue or prevent the process

A stigmergy-based analysis of city hotspots to discover trends and anomalies in urban transportation usage

A key aspect of a sustainable urban transportation system is the effectiveness of transportation policies. To be effective, a policy has to consider a broad range of elements, such as pollution emission, traffic flow, and human mobility. Due to the complexity and variability of these elements in the urban area, to produce effective policies remains a very challenging task. With the introduction of the smart city paradigm, a widely available amount of data can be generated in the urban spaces. Such data can be a fundamental source of knowledge to improve policies because they can reflect the sustainability issues underlying the city. In this context, we propose an approach to exploit urban positioning data based on stigmergy, a bio-inspired mechanism providing scalar and temporal aggregation of samples. By employing stigmergy, samples in proximity with each other are aggregated into a functional structure called trail. The trail summarizes relevant dynamics in data and allows matching them, providing a measure of their similarity. Moreover, this mechanism can be specialized to unfold specific dynamics. Specifically, we identify high-density urban areas (i.e hotspots), analyze their activity over time, and unfold anomalies. Moreover, by matching activity patterns, a continuous measure of the dissimilarity with respect to the typical activity pattern is provided. This measure can be used by policy makers to evaluate the effect of policies and change them dynamically. As a case study, we analyze taxi trip data gathered in Manhattan from 2013 to 2015.Comment: Preprin

Stigmergy-Based Modeling to Discover Urban Activity Patterns from Positioning Data

Positioning data offer a remarkable source of information to analyze crowds urban dynamics. However, discovering urban activity patterns from the emergent behavior of crowds involves complex system modeling. An alternative approach is to adopt computational techniques belonging to the emergent paradigm, which enables self-organization of data and allows adaptive analysis. Specifically, our approach is based on stigmergy. By using stigmergy each sample position is associated with a digital pheromone deposit, which progressively evaporates and aggregates with other deposits according to their spatiotemporal proximity. Based on this principle, we exploit positioning data to identify highdensity areas (hotspots) and characterize their activity over time. This characterization allows the comparison of dynamics occurring in different days, providing a similarity measure exploitable by clustering techniques. Thus, we cluster days according to their activity behavior, discovering unexpected urban activity patterns. As a case study, we analyze taxi traces in New York City during 2015

Contributo para o ordenamento territorial de infraestruturas de logística portuária

Tese de Doutoramento em Urbanismo, com a especialização em Urbanismo apresentada na Faculdade de Arquitetura da Universidade de Lisboa para obtenção do grau de Doutor.O alcance espacial e os efeitos de polarização territorial afectos à infraestrutura e actividade portuária têm sido uma preocupação patente nos estudos relacionados com as disciplinas do urbanismo e da geografia portuária. No entanto, são poucos os estudos em Portugal que analisam o efeito da actividade portuária nos diferentes sistemas territoriais – do internacional ao municipal – e quais as repercussões no ordenamento e planeamento do território. Na maioria dos casos verifica-se a inexistência de sistemas de monitorização da actividade logística-portuária, levando a que os processos de ordenamento e planeamento do território, a esta associada, sejam de natureza reactiva. Esta realidade, apresentada em Portugal, limita o potencial estratégico de que alguns territórios nacionais podem beneficiar em função do seu posicionamento nas Cadeias de Valor Globais. Esta tese argumenta que, dada a importância estratégica e a natureza quantitativa dos fluxos gerados nas infraestruturas portuárias do Arco Metropolitano de Lisboa, existe um potencial de organização territorial, e por conseguinte também urbano, associado à logística-portuária, que está localizado para além dos limites espaciais da infraestrutura portuária e que podem constituir, pela concentração e especialização de actividades no território, economias de escala que contribuam para a correção de distorções e assimetrias verificadas nos diferentes níveis de planeamento (Nacional, Regional e Local). Considerando os Conceitos associados ao desenvolvimento portuário, bem como as Politicas Públicas Europeias e Nacionais, a presente investigação visa explorar contributos para o planeamento e ordenamento da logística-portuária, no Arco Metropolitano de Lisboa, através do uso de dados relacionais, em particular dos fluxos de mercadorias dos portos de Lisboa, Setúbal e Sines. Este modelo, que é em parte simulado por ausência de dados de fluxos desagregados, documenta o potencial de análise territorial e urbana proveniente dos fluxos logístico-portuários, demonstrando possibilidades de hierarquização regional e urbana, bem como de identificação de fenómenos organizacionais. Por outro lado, este modelo demonstra igualmente as possibilidades de análise regional, sem constrangimentos de natureza administrativa, enquadrada nos conceitos de regionalização do sistema portuário. Os resultados da investigação evidenciam: i) a existência de conceitos de análise concorrentes no contexto dos territórios regionais e portuários; ii) a existência de fases de desenvolvimento do processo de regionalização do sistema portuário, em função do seu conhecimento, e o reconhecimento que no Arco Metropolitano de Lisboa este processo ainda é incipiente; e, iii) que o processo de regionalização do sistema portuário no Arco Metropolitano de Lisboa é um fenómeno estigmérgico. Perante estes resultados, os trabalhos futuros, focados nas relações funcionais, deverão incidir sobre: i) a elaboração de Plano Nacional de Logística-Portuária, reconhecendo a necessária capacitação institucional e tecnológica; e, ii) o desenvolvimento de investigação integrada na Estratégia de Investigação e Inovação para uma Especialização Inteligente.ABSTRACT: The spatial extent and effects of territorial polarization on infrastructure and port activity have been a clear concern in studies related to the disciplines of urbanism and port geography. However, there are few studies in Portugal that analyze the effect of port activity on the different territorial systems - from international to local - and the repercussions in the planning of territory. In most cases, there is a lack of monitoring systems for logistic-port activity, which means that planning processes of the associated territory are reactive in nature. This reality, presented in Portugal, limits the strategic potential that some national territories can benefit from depending on their position in the Global Value Chains. This thesis argues that, given the strategic importance and the quantitative nature of the flows generated in the port infrastructure of the Lisbon Metropolitan Arc, there is a potential for territorial, and therefore also urban, organization associated with port logistics, which is located beyond limits of the port infrastructure and that can contribute to the correction of distortions and asymmetries at different levels of planning (National, Regional and Local) by concentrating and specializing activities in the territory. Considering the Concepts associated with port development, as well as the European and National Public Policies, this research aims to explore contributions to the planning and ordering of port logistics in the Lisbon Metropolitan Arch through the use of relational data, in particular flows of goods from the ports of Lisbon, Setúbal and Sines. This model, which is partly simulated by lack of data on disaggregated flows, documents the potential of territorial and urban analysis from logistical-port flows, demonstrating possibilities of regional and urban hierarchization, as well as identification of organizational phenomena. On the other hand, this model also demonstrates the possibilities of regional analysis, without administrative constraints, framed in the concepts of regionalization of the port system. The research results show: i) the existence of concurrent analysis concepts in the context of regional and port territories; ii) the existence of stages of development of the process of regionalization of the port system, due to its knowledge, and the recognition that in the Lisbon Metropolitan Arc this process is still incipient; and iii) that the process of regionalization of the port system in the Lisbon Metropolitan Arch is a stigmergic phenomenon. In view of these results, future work, focused on functional relations, should focus on: i) the preparation of a National Port-Logistics Plan, recognizing the necessary institutional and technological capacity building; and (ii) the development of integrated research in the Research and Innovation Strategy for Intelligent Specialization.N/