Arquitetura da (in)segurança: estudando relações entre configuração espacial, artifícios de segurança e violência urbana no bairro Manaíra, João Pessoa, Paraíba

João Pessoa, the capital city of the state of Paraíba (Northeast Brazil), is reputed throughout the country as a quiet place, although it has been acquiring, over the past years, an urban character with social implications similar to those of major metropolitan Brazilian areas. The new situation is evident by the social inequalities, with the creation of confined spaces, which segregate and cause enclosure of the inhabitants, leading to death the public space. This study correlates accessibility in spatial structure with two types of crime data, burglary and robbery, recorded in 2008 and 2009, by the Secretaria de Segurança da Paraíba (The government agency public in charge of safety), in the district of Manaíra, an upper middle class neighborhood, which has, in recent times, been considered one of the most violent areas in João Pessoa. Sought to understand connections between these events and morpho-social aspects of the built environment, where examined the spatial properties, such as accessibility of the urban net, the presence of control measures, the safety of buildings and their uses. Spatial properties were also validated by the observation of pedestrian flows at strategic points of the study area. It was concluded that the presence of intense flows helps to attract potential thieves, physical security and control offers little protection

Gênese e evolução da região metropolitana de Maringá

Pós-graduação em Geografia - FCT

Aglomeração urbana de Londrina: integração territorial e intensificação de fluxos

Pós-graduação em Geografia - FCT

Um estudo sobre o processo de aglomeração urbana: Álvares Machado, Presidente Prudente e Regente Feijó

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Renda da terra e produção do espaço urbano em Jales - SP

Pós-graduação em Geografia - IGCE

Arquitetura da (in)segurança: estudando relações entre configuração espacial, artifícios de segurança e violência urbana no bairro Manaíra, João Pessoa, Paraíba

João Pessoa, the capital city of the state of Paraíba (Northeast Brazil), is reputed throughout the country as a quiet place, although it has been acquiring, over the past years, an urban character with social implications similar to those of major metropolitan Brazilian areas. The new situation is evident by the social inequalities, with the creation of confined spaces, which segregate and cause enclosure of the inhabitants, leading to death the public space. This study correlates accessibility in spatial structure with two types of crime data, burglary and robbery, recorded in 2008 and 2009, by the Secretaria de Segurança da Paraíba (The government agency public in charge of safety), in the district of Manaíra, an upper middle class neighborhood, which has, in recent times, been considered one of the most violent areas in João Pessoa. Sought to understand connections between these events and morpho-social aspects of the built environment, where examined the spatial properties, such as accessibility of the urban net, the presence of control measures, the safety of buildings and their uses. Spatial properties were also validated by the observation of pedestrian flows at strategic points of the study area. It was concluded that the presence of intense flows helps to attract potential thieves, physical security and control offers little protection

Arquitetura da (in)segurança: estudando relações entre configuração espacial, artifícios de segurança e violência urbana no bairro Manaíra, João Pessoa, Paraíba

João Pessoa, the capital city of the state of Paraíba (Northeast Brazil), is reputed throughout the country as a quiet place, although it has been acquiring, over the past years, an urban character with social implications similar to those of major metropolitan Brazilian areas. The new situation is evident by the social inequalities, with the creation of confined spaces, which segregate and cause enclosure of the inhabitants, leading to death the public space. This study correlates accessibility in spatial structure with two types of crime data, burglary and robbery, recorded in 2008 and 2009, by the Secretaria de Segurança da Paraíba (The government agency public in charge of safety), in the district of Manaíra, an upper middle class neighborhood, which has, in recent times, been considered one of the most violent areas in João Pessoa. Sought to understand connections between these events and morpho-social aspects of the built environment, where examined the spatial properties, such as accessibility of the urban net, the presence of control measures, the safety of buildings and their uses. Spatial properties were also validated by the observation of pedestrian flows at strategic points of the study area. It was concluded that the presence of intense flows helps to attract potential thieves, physical security and control offers little protection

Finding best urban routes based on analyses of high level and IOPT Petri net models

This paper presents a tool that combines two kinds of Petri Net analyses to set the fastest routes to one vehicle in a bounded area of traffic urban. The first analysis consists of the discovery of possible routes in a state space generated from an IOPT Petri net model given the initial marking as the vehicle position. The second analysis receives the routes found in the first analysis and calculates the state equations at incidence matrix created from the High Level Petri net model to define the fastest route for each vehicle that arrive in the roads. It was considered the exchange of information between vehicle and infrastructure (V2I) to get the position and speed of all vehicles and support the analyses. With the results obtained we conclude that is possible optimizing the urban traffic flow if this tool is applied to all vehicles in a bounded urban traffic. © 2012 IEEE.

Controlling traffic jams on urban roads modeled in Coloured Petri net using Genetic Algorithm

This paper presents an application to traffic lights control in congested urban traffic, in real time, taking as input the position and route of the vehicles in the involved areas. This data is obtained from the communication between vehicles and infrastructure (V2I). Due to the great complexity of the possible combination of traffic lights and the short time to get a response, Genetic Algorithm was used to optimize this control. According to test results, the application can reduce the number of vehicles in congested areas, even with the entry of vehicles that previously were not being considered in these roads, such as parked vehicles. © 2012 IEEE.

Optimizing urban traffic flow using genetic algorithm with petri net analysis as fitness function

This paper describes a new methodology adopted for urban traffic stream optimization. By using Petri net analysis as fitness function of a Genetic Algorithm, an entire urban road network is controlled in real time. With the advent of new technologies that have been published, particularly focusing on communications among vehicles and roads infrastructures, we consider that vehicles can provide their positions and their destinations to a central server so that it is able to calculate the best route for one of them. Our tests concentrate on comparisons between the proposed approach and other algorithms that are currently used for the same purpose, being possible to conclude that our algorithm optimizes traffic in a relevant manner.

An investigation of nucleation events in a coastal urban environment in the southern hemisphere

The occurrence of and conditions favourable to nucleation were investigated at an industrial and commercial coastal location in Brisbane, Australia during five different campaigns covering a total period of 13 months. To identify potential nucleation events, the difference in number concentration in the size range 14-30 nm (N14-30) between consecutive observations was calculated using first-order differencing. The data showed that nucleation events were a rare occurrence, and that in the absence of nucleation the particle number was dominated by particles in the range 30-300 nm. In many instances, total particle concentration declined during nucleation. There was no clear pattern in change in NO and NO2 concentrations during the events. SO2 concentration, in the majority of cases, declined during nucleation but there were exceptions. Most events took place in summer, followed by winter and then spring, and no events were observed for the autumn campaigns. The events were associated with sea breeze and long-range transport. Roadside emissions, in contrast, did not contribute to nucleation, probably due to the predominance of particles in the range 50-100 nm associated with these emissions.

Urban Informatics in Creative Industries

Presentation of research projects

Examination of relationships between urban form, household activities, and time allocation in the Atlanta Metropolitan Region

A substantial body of research is focused on understanding the relationships between socio-demographics, land-use characteristics, and mode specific attributes on travel mode choice and time-use patterns. Residential and commercial densities, inter-mixing of land uses, and route directness in conjunction with transportation performance characteristics interact to influence accessibility to destinations as well as time spent traveling and engaging in activities. This study uniquely examines the activity durations undertaken for out-of-home subsistence; maintenance, and discretionary activities. Also examined are total tour durations (summing all activity categories within a tour). Cross-sectional activities are obtained from household activity travel survey data from the Atlanta Metropolitan Region. Time durations allocated to weekdays and weekends are compared. The censoring and endogeneity between activity categories and within individuals are captured using multiple equations Tobit models. The analysis and modeling reveal that land-use characteristics such as net residential density and the number of commercial parcels within a kilometer of a residence are associated with differences in weekday and weekend time-use allocations. Household type and structure are significant predictors across the three activity categories, but not for overall travel times. Tour characteristics such as time-of-day and primary travel mode of the tours also affect traveler's out-of-home activity-tour time-use patterns.

Air ion concentrations in various urban outdoor environments

Atmospheric ions are produced by many natural and anthropogenic sources and their concentrations vary widely between different environments. There is very little information on their concentrations in different types of urban environments, how they compare across these environments and their dominant sources. In this study, we measured airborne concentrations of small ions, particles and net particle charge at 32 different outdoor sites in and around a major city in Australia and identified the main ion sources. Sites were classified into seven groups as follows: park, woodland, city centre, residential, freeway, power lines and power substation. Generally, parks were situated away from ion sources and represented the urban background value of about 270 ions cm-3. Median concentrations at all other groups were significantly higher than in the parks. We show that motor vehicles and power transmission systems are two major ion sources in urban areas. Power lines and substations constituted strong unipolar sources, while motor vehicle exhaust constituted strong bipolar sources. The small ion concentration in urban residential areas was about 960 cm-3. At sites where ion sources were co-located with particle sources, ion concentrations were inhibited due to the ion-particle attachment process. These results improved our understanding on air ion distribution and its interaction with particles in the urban outdoor environment.

Physical characteristics of small ions and their interaction with ultrafine particles in the urban environment

In recent years, the effect of ions and ultrafine particles on ambient air quality and human health has been well documented, however, knowledge about their sources, concentrations and interactions within different types of urban environments remains limited. This thesis presents the results of numerous field studies aimed at quantifying variations in ion concentration with distance from the source, as well as identifying the dynamics of the particle ionisation processes which lead to the formation of charged particles in the air. In order to select the most appropriate measurement instruments and locations for the studies, a literature review was also conducted on studies that reported ion and ultrafine particle emissions from different sources in a typical urban environment. The initial study involved laboratory experiments on the attachment of ions to aerosols, so as to gain a better understanding of the interaction between ions and particles. This study determined the efficiency of corona ions at charging and removing particles from the air, as a function of different particle number and ion concentrations. The results showed that particle number loss was directly proportional to particle charge concentration, and that higher small ion concentrations led to higher particle deposition rates in all size ranges investigated. Nanoparticles were also observed to decrease with increasing particle charge concentration, due to their higher Brownian mobility and subsequent attachment to charged particles. Given that corona discharge from high voltage powerlines is considered one of the major ion sources in urban areas, a detailed study was then conducted under three parallel overhead powerlines, with a steady wind blowing in a perpendicular direction to the lines. The results showed that large sections of the lines did not produce any corona at all, while strong positive emissions were observed from discrete components such as a particular set of spacers on one of the lines. Measurements were also conducted at eight upwind and downwind points perpendicular to the powerlines, spanning a total distance of about 160m. The maximum positive small and large ion concentrations, and DC electric field were observed at a point 20 m downwind from the lines, with median values of 4.4×103 cm-3, 1.3×103 cm-3 and 530 V m-1, respectively. It was estimated that, at this point, less than 7% of the total number of particles was charged. The electrical parameters decreased steadily with increasing downwind distance from the lines but remained significantly higher than background levels at the limit of the measurements. Moreover, vehicles are one of the most prevalent ion and particle emitting sources in urban environments, and therefore, experiments were also conducted behind a motor vehicle exhaust pipe and near busy motorways, with the aim of quantifying small ion and particle charge concentration, as well as their distribution as a function of distance from the source. The study found that approximately equal numbers of positive and negative ions were observed in the vehicle exhaust plume, as well as near motorways, of which heavy duty vehicles were believed to be the main contributor. In addition, cluster ion concentration was observed to decrease rapidly within the first 10-15 m from the road and ion-ion recombination and ion-aerosol attachment were the most likely cause of ion depletion, rather than dilution and turbulence related processes. In addition to the above-mentioned dominant ion sources, other sources also exist within urban environments where intensive human activities take place. In this part of the study, airborne concentrations of small ions, particles and net particle charge were measured at 32 different outdoor sites in and around Brisbane, Australia, which were classified into seven different groups as follows: park, woodland, city centre, residential, freeway, powerlines and power substation. Whilst the study confirmed that powerlines, power substations and freeways were the main ion sources in an urban environment, it also suggested that not all powerlines emitted ions, only those with discrete corona discharge points. In addition to the main ion sources, higher ion concentrations were also observed environments affected by vehicle traffic and human activities, such as the city centre and residential areas. A considerable number of ions were also observed in a woodland area and it is still unclear if they were emitted directly from the trees, or if they originated from some other local source. Overall, it was found that different types of environments had different types of ion sources, which could be classified as unipolar or bipolar particle sources, as well as ion sources that co-exist with particle sources. In general, fewer small ions were observed at sites with co-existing sources, however particle charge was often higher due to the effect of ion-particle attachment. In summary, this study quantified ion concentrations in typical urban environments, identified major charge sources in urban areas, and determined the spatial dispersion of ions as a function of distance from the source, as well as their controlling factors. The study also presented ion-aerosol attachment efficiencies under high ion concentration conditions, both in the laboratory and in real outdoor environments. The outcomes of these studies addressed the aims of this work and advanced understanding of the charge status of aerosols in the urban environment.