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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Assessing the Active Transportation Potential of Neighbourhood Models Using GIS

Cantell, Amber Marie January 2012 (has links)
This study sought to determine how five neighbourhood models (the Grid, Loop and Cul-de-Sac, Fused Grid, New Urbanist and Greenway) compare in terms of the characteristics known to affect active transportation rates, and which model is most likely to be able to facilitate active transportation as a result. In order to do so, model principles and design characteristics of case study neighbourhoods were described and used to create a range of design specifications for each model. These specifications were then used to develop a GIS-based representation of an example neighbourhood for each model, which included the transportation network, parcels of different land use types and densities, homes and destinations. GIS, statistical and graph-based techniques were then used to comprehensively assess and compare the models in terms of their potential to facilitate walking and biking through the built environment correlates identified in through a literature review. The models were ranked on each variable, and then an overall comparison was made on the basis diversity (land use mix), density and design - the three dimensions identified by Cervero and Kockelman (1997) as being the key ways through which the built environment can contribute to creating walkable (and potentially bikeable) neighbourhoods. Additional measures related to trip characteristics and issues of importance to developers (such as buildable area) were also included. The results illustrate how each model’s unique approach to facilitating walking and/or biking is reflected in the built environment characteristics assessed. While a model that was strong in one category was often weaker in another (a finding which echoes that of Filion and Hammond, 2003), the three alternative models (Fused Grid, New Urbanist and Greenway) consistently fared better than the more traditional Grid and Loop and Cul-de-Sac designs, with the New Urbanist scoring the highest on the overall evaluation of walkability and bikeability and the Greenway the best on network design for cyclists. In addition to these findings, the study also provided an opportunity to explore several challenges related to model assessment, such as issues arising from frame choice, off-set networks, and the use of roads as proxies for active transportation networks.
72

Assessing the Active Transportation Potential of Neighbourhood Models Using GIS

Cantell, Amber Marie January 2012 (has links)
This study sought to determine how five neighbourhood models (the Grid, Loop and Cul-de-Sac, Fused Grid, New Urbanist and Greenway) compare in terms of the characteristics known to affect active transportation rates, and which model is most likely to be able to facilitate active transportation as a result. In order to do so, model principles and design characteristics of case study neighbourhoods were described and used to create a range of design specifications for each model. These specifications were then used to develop a GIS-based representation of an example neighbourhood for each model, which included the transportation network, parcels of different land use types and densities, homes and destinations. GIS, statistical and graph-based techniques were then used to comprehensively assess and compare the models in terms of their potential to facilitate walking and biking through the built environment correlates identified in through a literature review. The models were ranked on each variable, and then an overall comparison was made on the basis diversity (land use mix), density and design - the three dimensions identified by Cervero and Kockelman (1997) as being the key ways through which the built environment can contribute to creating walkable (and potentially bikeable) neighbourhoods. Additional measures related to trip characteristics and issues of importance to developers (such as buildable area) were also included. The results illustrate how each model’s unique approach to facilitating walking and/or biking is reflected in the built environment characteristics assessed. While a model that was strong in one category was often weaker in another (a finding which echoes that of Filion and Hammond, 2003), the three alternative models (Fused Grid, New Urbanist and Greenway) consistently fared better than the more traditional Grid and Loop and Cul-de-Sac designs, with the New Urbanist scoring the highest on the overall evaluation of walkability and bikeability and the Greenway the best on network design for cyclists. In addition to these findings, the study also provided an opportunity to explore several challenges related to model assessment, such as issues arising from frame choice, off-set networks, and the use of roads as proxies for active transportation networks.
73

A General Vehicle Routing Problem

Goel, Asvin, Gruhn, Volker 17 January 2019 (has links)
In this paper, we study a rich vehicle routing problem incorporating various complexities found in real-life applications. The General Vehicle Routing Problem (GVRP) is a combined load acceptance and generalised vehicle routing problem. Among the real-life requirements are time window restrictions, a heterogeneous vehicle fleet with different travel times, travel costs and capacity, multi-dimensional capacity constraints, order/vehicle compatibility constraints, orders with multiple pickup, delivery and service locations, different start and end locations for vehicles, and route restrictions for vehicles. The GVRP is highly constrained and the search space is likely to contain many solutions such that it is impossible to go from one solution to another using a single neighbourhood structure. Therefore, we propose iterative improvement approaches based on the idea of changing the neighbourhood structure during the search.
74

Injury and Neighborhood Marginalization: Does it Matter Where You Live?

Lee, Patricia Pui Shuen 15 February 2010 (has links)
Background: Injury is an enormous public health problem in Canada. Recent studies have suggested that characteristics of the residential environment, particularly neighborhood marginalization, may be important in determining injury risk. Objective: To determine whether there is an association between neighborhood marginalization and injury in the largest urban cities of Ontario. Methods: A retrospective, cross-sectional, ecological study was conducted to evaluate the relationship between neighborhood marginalization and injury in 0-64 year olds who resided in the ten largest cities of Ontario between 2003-2005. Results: Neighborhoods with high levels of ethnic diversity had significantly lower rates of unintentional injuries, neighborhoods with high levels of material deprivation had significantly higher rates of assaults, and neighborhoods with high levels of residential instability and material deprivation had significantly higher rates of self-inflicted injuries in adults. Conclusions: The association between neighborhood marginalization and injury differs depending on the type of injury examined.
75

Injury and Neighborhood Marginalization: Does it Matter Where You Live?

Lee, Patricia Pui Shuen 15 February 2010 (has links)
Background: Injury is an enormous public health problem in Canada. Recent studies have suggested that characteristics of the residential environment, particularly neighborhood marginalization, may be important in determining injury risk. Objective: To determine whether there is an association between neighborhood marginalization and injury in the largest urban cities of Ontario. Methods: A retrospective, cross-sectional, ecological study was conducted to evaluate the relationship between neighborhood marginalization and injury in 0-64 year olds who resided in the ten largest cities of Ontario between 2003-2005. Results: Neighborhoods with high levels of ethnic diversity had significantly lower rates of unintentional injuries, neighborhoods with high levels of material deprivation had significantly higher rates of assaults, and neighborhoods with high levels of residential instability and material deprivation had significantly higher rates of self-inflicted injuries in adults. Conclusions: The association between neighborhood marginalization and injury differs depending on the type of injury examined.
76

Planering av stränggjutningsproduktion : En heruistisk metod

Äng, Oscar, Trygg, Alexander January 2017 (has links)
Detta arbete syftar till att undersöka om det är möjligt att med en heuristisk metod skapa giltiga lösningar till ett problem vid planering av stränggjutningsproduktion på SSAB. Planeringsproblemet uppstår när stål av olika sorter ska gjutas under samma dag. Beroende på i vilken ordning olika kundordrar av stål gjuts uppstår spill av olika storlek. Detta spill ska minimeras och tidigare arbete har genomförts på detta problem och resulterat i en matematisk modell för att skapa lösningar till problemet. Det tar i praktiken lång tid att hitta bra lösningar med modellen och frågeställningen är om det går att göra detta med en heuristisk metod för att kunna generera bra lösningar snabbare. Med inspiration från Variable Neighbourhood Search, Simulated Annealing och tabusökning har heuristiker skapats, implementerats och utvärderats mot den matematiska modellen. En av heuristikerna presterar bättre än den matematiska modellen gör på 10 minuter. Matematiska modellens resultat efter 60 minuter körtid är bättre än den utvecklade heuristiken, men resultaten är nära varandra. Körtiden för heuristiken tar signifikant mindre tid än 10 minuter. / This study aims to investigate if it is possible to use a heuristic method to create feasible solution in a Cast Batching Problem at SSAB. The problem occurs when different kinds of steel should be cast during the same day. Depending on which order the groups of different steel is placed different amounts of waste is produced, the goal is to minimize this waste. Earlier work has been done on this problem and resulted in a mathematical model to create feasible solutions to this problem. In practice the time it takes to create good solutions are long and the question is if it is possible to use a heuristic method to generate good solutions in a shorter amount of time. Drawing upon inspiration from metaheuristics such as Variable Neighbourhood Search, Simualted Annealing and Tabu Search multiple heuristics have been created, implemented and evaluated against the mathematical model. One of the heuristics perform better than the mathematical model does in 10 minutes. The result from the mathematical model after 60 minutes is slightly better than the heuristic, but the results are similar. With regards to running time the heuristic takes considerably less time than 10 minutes.
77

Monomial Cellular Automata : A number theoretical study on two-dimensional cellular automata in the von Neumann neighbourhood over commutative semigroups

Fransson, Linnea January 2016 (has links)
In this report, we present some of the results achieved by investigating two-dimensional monomial cellular automata modulo m, where m is a non-zero positive integer. Throughout the experiments, we work with the von Neumann neighbourhood and apply the same local rule based on modular multiplication. The purpose of the study is to examine the behaviour of these cellular automata in three different environments, (i.e. the infinite plane, the finite plane and the torus), by means of elementary number theory. We notice how the distance between each pair of cells with state 0 influences the evolution of the automaton and the convergence of its configurations. Similar impact is perceived when the cells attain the values of Euler's-<img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cphi" />function or of integers with common divisors with m, when m &gt; 2. Alongside with the states of the cells, the evolution of the automaton, as well as the convergence of its configurations, are also decided by the values attributed to m, whether it is a prime, a prime power or a multiple of primes and/or prime powers.
78

Perceived neighbourhood insecurity and psychosomatic health complaints among adolescents in Stockholm : Exploring district-level and gendered inequalities

Abrahamsson, Klara January 2016 (has links)
The neighbourhood is an essential arena for adolescents’ health development and research suggests that perceived neighbourhood insecurity (PNI) is associated with socio-economic status and self-rated health. The present study explored the distribution of adolescents’ PNI and its association with psychosomatic health complaints across districts. It also examined gender differences and whether family socio-economic position, foreign background and previous exposure to crime could explain part of the association. Data came from classroom-surveys within Stockholm municipality’s 14 districts in 2010, 2012 and 2014 (n=10,291). Linear and logistic multilevel regression models were applied. Results showed that the average level of PNI varied considerably between districts and were strongly connected to its socio-demographic composition. However, individual characteristics in terms of family background and previous exposure to crime only explained a minor part of the variation in PNI across districts. Girls reported more insecurity than boys in all districts. Gender differences in PNI decreased in absolute numbers, but increased in relative numbers, as the overall ‘neighbourhood safety’ increased. Between-district differences in health were minor, but PNI was still a strong predictor of individual-level health, especially for boys. Furthermore, the predictive power of PNI on health was stronger in districts perceived as safer.
79

With a little help from our friends : The European Union and its relation to Ukraine concerning regional cooperation

Sjölund, Mikael January 2007 (has links)
<p>This study examines the European Unions (EU) promoting of regional cooperation, included in its programme, the European Neighbourhood Policy (ENP). The thesis is based upon the agreed activities in the EU/Ukraine relation concerning regional cooperation.</p><p>The aim for this thesis is to visualise the policy outcome of the ENP concerning the EU/Ukraine relation and regional cooperation. The following questions are posed: What are the goals for the EU; what are the achievements and planned actions and what instruments are used by the EU in the ENP concerning the EU/Ukraine relation and regional cooperation?</p><p>The theoretical approach assumes that the Union is a power in international relations. It’s well suited promoting its policies in an asymmetric power environment, where the EU is the supremacy.</p><p>This study is conducted with a qualitative research method, based on text analysis on the European Unions official documents.</p><p>The result shows that the goals for the Union are the protection of its prosperity and its energy supply. Ukraine shall assist the EU, reaching these goals. In exchange, is the EU promising integration to the Unions internal market for Ukraine. But the EU has problems when this contravenes to Russia’s interests. This confirms the theory.</p>
80

The Impacts Of Neighbourhood Traffic Management

David Daniel, Basil January 2012 (has links)
A major traffic-related problem faced by residents is speeding, which not only causes safety concerns, but also noise issues. Traffic calming is a much favoured traffic management tool employed by road controlling authorities to primarily reduce vehicle speed, hence improve community liveability. This research aimed to investigate the impacts of traffic calming on speed, safety and traffic noise. The objectives included developing models for the prediction of speed and noise on traffic-calmed streets, and providing guidance for good design practices. Speeds of individual vehicles as they approached and crossed traffic calming devices were observed in order to identify the behaviour of individual drivers. Results indicated that the speed hump and the raised angled slow point produced the largest speed reductions and least variation in speeds, while mid-block narrowings had no significant speed changes. Inter-device speed was found to be mainly controlled by the separation between devices. 85th percentile speeds at distances from calming devices were 40 – 45 km/h for vertical deflections and 45 – 55 km/h for horizontal deflections. Speeds on approach to speed humps were found to be influenced by the distance available on the approaches, while operating speed at the speed humps were partly influenced by the hump width relative to the road width. There was evidence of safety benefits of traffic calming overall, despite mid-block crashes increasing post-calming. However, there was no association between the traffic calming and the crashes, which appeared to probably be due to other factors, human factors in particular. Noise levels produced by light vehicles across speed humps were in fact lower than on a flat section of road, given their respective mean speeds. At a reference speed of 25 km/h, noise levels produced over the 100 mm hump were 3.6 dBA higher than those produced by the 75 mm hump.

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