38 resultados para Urban space reproduction


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In this paper, we propose an algorithm for an upgrading arc median shortest path problem for a transportation network. The problem is to identify a set of nondominated paths that minimizes both upgrading cost and overall travel time of the entire network. These two objectives are realistic for transportation network problems, but of a conflicting and noncompensatory nature. In addition, unlike upgrading cost which is the sum of the arc costs on the path, overall travel time of the entire network cannot be expressed as a sum of arc travel times on the path. The proposed solution approach to the problem is based on heuristic labeling and exhaustive search techniques, in criteria space and solution space, respectively. The first approach labels each node in terms of upgrading cost, and deletes cyclic and infeasible paths in criteria space. The latter calculates the overall travel time of the entire network for each feasible path, deletes dominated paths on the basis of the objective vector and identifies a set of Pareto optimal paths in the solution space. The computational study, using two small-scale transportation networks, has demonstrated that the algorithm proposed herein is able to efficiently identify a set of nondominated median shortest paths, based on two conflicting and noncompensatory objectives.

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This paper proposes an alternative algorithm to solve the median shortest path problem (MSPP) in the planning and design of urban transportation networks. The proposed vector labeling algorithm is based on the labeling of each node in terms of a multiple and conflicting vector of objectives which deletes cyclic, infeasible and extreme-dominated paths in the criteria space imposing cyclic break (CB), path cost constraint (PCC) and access cost parameter (ACP) respectively. The output of the algorithm is a set of Pareto optimal paths (POP) with an objective vector from predetermined origin to destination nodes. Thus, this paper formulates an algorithm to identify a non-inferior solution set of POP based on a non-dominated set of objective vectors that leaves the ultimate decision to decision-makers. A numerical experiment is conducted using an artificial transportation network in order to validate and compare results. Sensitivity analysis has shown that the proposed algorithm is more efficient and advantageous over existing solutions in terms of computing execution time and memory space used.

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Urban Sustainability expresses the level of conservation of a city while living a town or consuming its urban resources, but the measurement of urban sustainability depends on what are considered important indicators of conservation besides the permitted levels of consumption in accordance with adopted criteria. This criterion should have common factors that are shared for all the members tested or cities to be evaluated as in this particular case for Abu Dhabi, but also have specific factors that are related to the geographic place, community and culture, that is the measures of urban sustainability specific to a middle east climate, community and culture where GIS Vector and Raster analysis have a role or add a value in urban sustainability measurements or grading are considered herein. Scenarios were tested using various GIS data types to replicate urban history (ten years period), current status and expected future of Abu Dhabi City setting factors to climate, community needs and culture. The useful Vector or Raster GIS data sets that are related to every scenario where selected and analysed in the sense of how and how much it can benefit the urban sustainability ranking in quantity and quality tests, this besides assessing the suitable data nature, type and format, the important topology rules to be considered, the useful attributes to be added, the relationships which should be maintained between data types of a geo- database, and specify its usage in a specific scenario test, then setting weights to each and every data type representing some elements of a phenomenon related to urban suitability factor. The results of assessing the role of GIS analysis provided data collection specifications such as the measures of accuracy reliable to a certain type of GIS functional analysis used in an urban sustainability ranking scenario tests. This paper reflects the prior results of the research that is conducted to test the multidiscipline evaluation of urban sustainability using different indicator metrics, that implement vector GIS Analysis and Raster GIS analysis as basic tools to assist the evaluation and increase of its reliability besides assessing and decomposing it, after which a hypothetical implementation of the chosen evaluation model represented by various scenarios was implemented on the planned urban sustainability factors for a certain period of time to appraise the expected future grade of urban sustainability and come out with advises associated with scenarios for assuring gap filling and relative high urban future sustainability. The results this paper is reflecting are concentrating on the elements of vector and raster GIS analysis that assists the proper urban sustainability grading within the chosen model, the reliability of spatial data collected; analysis selected and resulted spatial information. Starting from selecting some important indicators to comprise the model which include regional culture, climate and community needs an example of what was used is Energy Demand & Consumption (Cooling systems). Thus, this factor is related to the climate and it‟s regional specific as the temperature varies around 30-45 degrees centigrade in city areas, GIS 3D Polygons of building data used to analyse the volume of buildings, attributes „building heights‟, estimate the number of floors from the equation, following energy demand was calculated and consumption for the unit volume, and compared it in scenario with possible sustainable energy supply or using different environmental friendly cooling systems this is followed by calculating the cooling system effects on an area unit selected to be 1 sq. km, combined with the level of greenery area, and open space, as represented by parks polygons, trees polygons, empty areas, pedestrian polygons and road surface area polygons. (initial measures showed that cooling system consumption can be reduced by around 15 -20 % with a well-planned building distributions, proper spaces and with using environmental friendly products and building material, temperature levels were also combined in the scenario extracted from satellite images as interpreted from thermal bands 3 times during the period of assessment. Other examples of the assessment of GIS analysis to urban sustainability took place included Waste Productivity, some effects of greenhouse gases measured by the intensity of road polygons and closeness to dwelling areas, industry areas as defined from land use land cover thematic maps produced from classified satellite images then vectors were created to take part in defining their role within the scenarios. City Noise and light intensity assessment was also investigated, as the region experiences rapid development and noise is magnified due to construction activities, closeness of the airports, and highways. The assessment investigated the measures taken by urban planners to reduce degradation or properly manage it. Finally as a conclusion tables were presented to reflect the scenario results in combination with GIS data types, analysis types, and the level of GIS data reliability to measure the sustainability level of a city related to cultural and regional demands.

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This paper proposes an efficient solution algorithm for realistic multi-objective median shortest path problems in the design of urban transportation networks. The proposed problem formulation and solution algorithm to median shortest path problem is based on three realistic objectives via route cost or investment cost, overall travel time of the entire network and total toll revenue. The proposed solution approach to the problem is based on the heuristic labeling and exhaustive search technique in criteria space and solution space of the algorithm respectively. The first labels each node in terms of route cost and deletes cyclic and infeasible paths in criteria space imposing cyclic break and route cost constraint respectively. The latter deletes dominated paths in terms of objectives vector in solution space in order to identify a set of Pareto optimal paths. The approach, thus, proposes a non-inferior solution set of Pareto optimal paths based on non-dominated objective vector and leaves the ultimate decision to decision-makers for purpose specific final decision during applications. A numerical experiment is conducted to test the proposed algorithm using artificial transportation network. Sensitivity analyses have shown that the proposed algorithm is advantageous and efficient over existing algorithms to find a set of Pareto optimal paths to median shortest paths problems.

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Historic architectural heritage is important to sustainable urban planning policy, particularly in cities that have heritage sites and/or themselves have ancient archaeological value. Delhi is one of the oldest living cities in the world. However, the vision of its planning policy is limited to valuing heritage for itself and for its economic value instead of also exploring the ways in the city’s heritage might contribute to the social organisation and utilisation of the urban public space. Particularly, like most national policy documents on heritage, it ignores the heritage/gender nexus, which has implications for the identity and status of women in Delhi, community development and ecological preservation. But twenty women practioners and scholars of development in Delhi referred to heritage as a challenge as well as opportunity for gender and urban sustainability when asked for their perspectives on the most important sustainability issues in the city. I argue that Delhi’s urban planning strategies must acknowledge the gender/heritage nexus to enable holistic and gender-inclusive urban development for the present and future generations of its citizens, which is an important thrust of the sustainability agenda.

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Educational campaigning has received little attention in the literature. This study investigates long-term and organised urban campaigns that are collectively lobbying the Victorian State Government in Australia, for a new public high school to be constructed in their suburb. A public high school is also known as a state school, government school, or an ordinary comprehensive school. It receives the majority of its funding from the State and Federal Australian Government, and is generally regarded as ‘free’ education, in comparison to a private school. Whilst the campaigners frame their requests as for a ‘public school’, their primary appeal is for a local school in their community. This study questions how collective campaigning for a locale-specific public school is influenced by geography, class and identity. In order to explore these campaigns, I draw on formative studies of middle-class school choice from an Australian and United Kingdom perspective (Campbell, Proctor, & Sherington, 2009; Reay, Crozier, & James, 2011). To think about the role of geography and space in these processes of choice, I look to apply Harvey’s (1973) theory of absolute, relational and relative space. I use Bourdieu (1999b) as a sociological lens that is attentive to “site effects” and it is through this lens that I think about class as a “collection of properties” (Bourdieu, 1984, p. 106), actualised via mechanisms of identity and representation (Hall, 1996; Rose, 1996a, 1996b). This study redresses three distinct gaps in the literature: first, I focus attention on a contemporary middle-class choice strategy—that is, collective campaigning for a public school. Research within this field is significantly under-developed, despite this choice strategy being on the rise. Second, previous research argues that certain middle-class choosers regard the local public school as “inferior” in some way (Reay, et al., 2011, p. 111), merely acting as a “safety net” (Campbell, et al., 2009, p. 5) and connected to the working-class chooser (Reay & Ball, 1997). The campaigners are characteristic of the middle-class school chooser, but they are purposefully and strategically seeking out the local public school. Therefore, this study looks to build on work by Reay, et al. (2011) in thinking about “against-the-grain school choice”, specifically within the Australian context. Third, this study uses visual and graphic methods in order to examine the influence of geography in the education market (Taylor, 2001). I see the visualisation of space and schooling that I offer in this dissertation as a key theoretical contribution of this study. I draw on a number of data sets, both qualitative and quantitative, to explore the research questions. I interviewed campaigners and attended campaign meetings as participant observer; I collected statistical data from fifteen different suburbs and schools, and conducted comparative analyses of each. These analyses are displayed by using visual graphs. This study uses maps created by a professional graphic designer and photographs by a professional photographer; I draw on publications by the campaigners themselves, such as surveys, reports and social media; but also, interviews with campaigners that are published in local or state newspapers. The multiple data sets enable an immersive and rich graphic ethnography. This study contributes by building on understandings of how particular sociological cohorts of choosers are engaging with, and choosing, the urban public school in Australia. It is relevant for policy making, in that it comes at a time of increasing privatisation and a move toward independent public schools. This study identifies cohorts of choosers that are employing individual and collective political strategies to obtain a specific school, and it identifies this cohort via explicit class-based characteristics and their school choice behaviours. I look to use fresh theoretical and methodological approaches that emphasise space and geography, theorising geo-identity and the pseudo-private school

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Market Square was a public reserve located in the centre of the Victorian regional city of Geelong. It was established by Governor Sir George Gipps during the initial surveying of the area in 1838. The square later became a produce market, before being progressively built upon for public and commercial purposes. Today, the modern Market Square Shopping Centre occupies a substantial portion of the original site. Opened in 1985 by the City of Geelong, the complex initially drew high rental incomes for the Council. However, by the early 1990s revenue began to decline after the collapse of the Pyramid Building Society and competition from the new Bay City Plaza shopping centre (now Westfield) that was built directly opposite. In 1993 the city council decided to sell the complex. Today it remains privately owned and while it adjoins the Little Malop Street Mall which was also part of the original public square, its connection with the surrounding urban environment is poor. The introverted architectural nature of Geelong’s two large retail shopping complexes has significantly altered the city’s spatial dynamic. The traditional intimate urban structure and streetscape has been fragmented. This has led to a deterioration of the city’s social cohesion, sense of place and economic prosperity. This paper chronicles the myriad errors of judgement by the institution of local government that have contributed to this situation. Heeding past mistakes, it explores ways in which the Council might work with private landowners to improve the permeability of the city’s public urban spaces and internalised retail centres for improved use, integration, functionality and resilience. Achieving a shared culture of concern for the city’s urban fabric presents some significant challenges. How might ‘big box’ shopping centres be reconsidered to make a positive contribution to the city’s urban spatial network while remaining commercially viable? The built environment has an important role to play in addressing the problem by presenting opportunities for these new urban institutions to also benefit from stronger connections between the public and private realm.

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Bicycle advisory treatments are used to advise road users of the potential presence of cyclists and of the location where cyclists may be expected to ride on a road. They include pavement markings, warning signs, guide signs, and as such have no regulatory function. The most common type of bicycle advisory pavement markings is the shared lane marking. Other forms of bicycle advisory pavement marking have also been trialled and used in several local jurisdictions. The bicycle awareness zone is an example of such facility which has been trialled and used in southeast Queensland, Australia since the late 1990s. A bicycle awareness zone is similar to shared lane marking in principle but differs in the type of logo and, in some cases, location of its placement on the road. This study assesses the operational and safety issues at three bicycle awareness zone sites by analysing video-assisted observation data collected in 2011 by Queensland Department of Transport and Main Roads, Australia. Of the several applications of bicycle awareness zones, this study only covers a particular application where the centre of the bicycle symbol is placed exactly over the parking edge line. Unlike previous studies, which mostly covered before-and-after evaluations of bicycle advisory pavement markings, the focus of this study is to assess whether the placement of bicycle awareness zone symbols has been successful. The aggregated results from video-assisted observational data show that the cyclists did not always track themselves over the centre of the symbols. Rather, both the cyclists' lateral tracking positions and road user interactions varied with the widths of kerbside parallel parking space. Since the bicycle awareness zone symbols are not positioned on the cyclists' desired line of ride on some roads, their operational effectiveness and safety value are questioned.