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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.
81

Measuring what matters : comparing the lived experience to objective measures of accessibility

Curl, Angela January 2013 (has links)
Accessibility is an enduring concept in Transport Planning, historically relating to the performance of the transport system and more recently to the understanding of social aspects of transport planning and practice. Accessibility Planning, set in the context of addressing social exclusion, is one example of an applied approach to accessibility which seeks to reflect user perspectives. However, translating the concept into practice is problematic. Measurement is dominated by time and distance and separation of people from destinations, rather than reflecting individuals’ perceptions. The core aims of this thesis are to critically appraise dominant approaches to Accessibility Planning and to understand how objective measures relate to perceptions of accessibility. The thesis is structured into two main empirical stages. Firstly a review of current approaches is undertaken through engagement with accessibility practitioners in England and a comparative analysis of accessibility measures in the English Core Accessibility Indicators and National Travel Survey. Secondly a mixed methods case study, utilising household survey and mental mapping interviews in Greater Nottingham, is presented. Statistical analyses are used to compare objective and self-reported measures of accessibility and to explore factors contributing to perceptions of accessibility. Perceived accessibility is more strongly related to selfreported measures than to objective measures. Demographic characteristics and attitudes are also important in explaining variation in perceptions. For example, while an elderly person may perceive accessibility to be worse because of physical mobility issues, car users may perceive inaccessibility due to lack of awareness of alternatives, leading to different policy approaches. A grounded theory analysis of interview data highlights that affective and symbolic factors are useful in understanding perceptions of accessibility, in addition to the instrumental factors more usually studied. Recommendations include a need to incorporate subjective measurement alongside more traditional accessibility measures, in line with wider policy discourses such as the recent development of subjective wellbeing measures by the Office for National Statistics.
82

Resilience to food insecurity: Measuring access to food in the urban environment

Reynolds, Stuart David January 2014 (has links)
Food security in urban environments is becoming an increasingly important issue worldwide; urban expansion and urban infilling means that city populations are rising while the amount of available land for growing food is reducing. Accessibility of food, in regards to potential food growing space and food retail locations at the household level, is a key indicator for determining how resilient households are to food insecurity. This thesis investigates accessibility of food in urban environments, and a methodology has been developed that employs a non location-specific data structure that assigns resilience categories to individual households. User-defined input variables for the amount of food-growing space required per person, and the maximum travel distance allowed, mean that different scenarios can be created. Two case studies of Christchurch and Stockholm are used to demonstrate how different datasets can be incorporated to give insight into the levels of resilience to food insecurity. Examples of potential sources of error caused by the variations in input dataset quality have been uncovered in the case studies, and possible strategies for dealing with these sources of error are discussed. Results of this study showed that greater maximum travel distances play a key role in accessibility of food in the urban environment, and that both cities are reliant on food retailers to supply food to the urban population, even when potential food growing space is taken into account. City planners or decision-makers can use the methodology developed in this thesis to make decisions about where potential growing space needs to be protected or allocated. They can also use it to model the potential effects of different scenarios, such as the addition of new subdivisions or changes in land use for public land.
83

The Influence of Sociodemographic and Land Use Patterns on Public Transport Use in Christchurch, New Zealand

Wright, Edward Peter Nelson January 2010 (has links)
This thesis investigated the links between public transport use and sociodemographic and land use factors. A dataset of address information about regular bus smartcard users was sourced. These addresses were geocoded using Geographical Information Systems, and the address points derived through this process were used to calculate the percentage of regular bus users in Census meshblock spatial areas. This percentage was then compared to a number of different factors, including deprivation levels (a measure of sociodemographic status), average distance to the nearest bus stop and bus route, and a number of variables from the New Zealand Census of Population and Dwellings, using a number of forms of analysis. The number of cardholders in different residential zonings was assessed, along with the average number of trips taken per day by cardholders. Results indicate that there was a relationship between the regular Metrocard users and deprivation, and regular Metrocard users and land use, however the statistical validity of these relationships was low. Principal component analysis and regression analysis were carried out to assess what variables best explained the proportion of bus use. It was found that the presence of International Students in an area accounted for the biggest variation in the levels of bus use, along with people who were Unemployed and of Maori or Pacific ethnicity, and people who have limited access to vehicles. However, the statistical validity of these results was again low.
84

Using a natural experiment to assess the effect of spatial barriers on health service utilization.

MacRae, Jayden January 2014 (has links)
The closure of the Manawatu Gorge in August 2011 caused a change in the travel time for patients living in the eastern area of the MidCentral Health District to their main hospital and health services located in Palmerston North. This presented an opportunity to study the effect a change in travel time and spatial access had on a population before and after such an event. This study used a retrospective cohort design, using routinely collected data from general practice, emergency department, hospital admissions and outpatient services. The investigation was completed using novel geospatial information systems methods to produce high fidelity data for analysis with free and open source software by developing and validating two new methods of improving geocoding data quality and a new travel time prediction model. Potential and realised spatial accessibility measures were calculated for 101,456 patients over 3.5 years while the gorge was both open and closed. Catchment sensitivity analysis and two-step floating catchment area using distance decays presented complimentary evidence of accessibility change during the Manawatu Gorge closure. Analysis of utilisation measures in both primary and secondary care were correlated with travel time. Utilisation of general practice services appeared to be negatively impacted by increased travel time when comparing realised accessibility in a control and intervention group during the gorge closure. It appeared as though other factors affected access to health services to a greater degree than an increase of up to fifteen minutes travel time.
85

Winter 'n' Wheels study: Understanding experiences of key stakeholder groups regarding sidewalks accessibility in winter for wheeled mobility device users.

Joshi, Deepak 20 October 2014 (has links)
Community participation during the cold winter months is difficult for wheeled mobility device (WMD) users. However, limited attention has been given to understanding this problem, and collaboratively identifying solutions with stakeholders. This qualitative study explored the issues faced by key stakeholders (WMD users and Public Works Department employees) regarding use and provision of accessible sidewalks in winter and identified solutions. Eleven participants informed the study through a combination of go-along interviews, key informant interviews, photographs, and meteorological data. Four themes were identified: the context of winter season, winter and wheels interact, winter versus the city, and a framework for winter access and success. Solutions included creating awareness, taking action, and assuming accountability through collaborative efforts and increased information sharing. Based on the perspectives of informed stakeholders this study contributes to the development of focused interventions for overcoming winter sidewalk barriers and thus, enabling winter community participation of WMD users.
86

Binding of Self-assembling Peptides to Oligodeoxynucleotides

Wang, Mei January 2007 (has links)
This thesis is an experimental investigation on the binding of self-assembling peptides to oligodeoxynucleotides (ODNs) and the characterization of the resulting peptide-ODN complexes/aggregates, the first key step in the development of a peptide-based gene delivery system. Effects of pH, charge distribution along the peptide backbone, and oligonucleotide sequences on the peptide-ODN binding were investigated by a series of physicochemical methods. UV-Vis absorption and fluorescence anisotropy experiments demonstrate that aggregates are formed after mixing the peptide and ODN in aqueous solution. The aggregates in solution can be centrifuged out. Based on this property, the fraction of ODNs incorporated in the peptide-ODN aggregates can be obtained by comparing the UV-Vis absorption of the solution before and after centrifugation. Binding isotherms are generated by a binding density function analysis of the UV absorbance results. The binding parameters are extracted from the analysis of the binding isotherms based on the McGhee and von Hippel model. Equilibrium binding parameter studies show that the binding of two self-assembling peptides, EAK16-II and EAK 16-IV, to model single and double-stranded ODNs at pH 4 is stronger than at pH 7, and that no binding occurs at pH 11. These results demonstrate that electrostatic interactions play an important role in the EAK-ODN binding because EAKs are more positively charged at low pH. EAKs bind more strongly to dG16 than to the other ODN sequences dC16 and dGC16. This demonstrates that the hydrogen bond might be involved because they promote the binding of the lysine residues of the peptide to dG16 to a greater extent than to dC16. The charge distribution along the peptides is found to have an effect on the binding. EAK16-IV, whose positively charged residues are clustered at one end of the peptide, binds to the ODNs more strongly than EAK16-II, whose positively charged residues are distributed throughout the peptide chain, at the same pH. The binding process of EAKs to the ODNs was investigated by fluorescence anisotropy and static light scattering experiments. The results show that individual EAK and ODN molecules complex first, followed by the aggregation of these complexes into large aggregates. The nature of the resulting peptide-ODN complexes/aggregates is examined by UV-Vis absorption, fluorescence anisotropy, and PAGE experiments. The results demonstrate that free EAK, free ODNs, and small EAK-ODN complexes, which can not be centrifuged out, exist in the supernatant, and that large aggregates are collected in the pellets after centrifugation of the solution. The size of the resulting EAK-ODN complexes/aggregates measured by AFM and DLS is around a few hundreds of nanometers at low EAK concentrations. The accessibility of the ODNs to the quencher in the solution is reduced by 40 % and 60 % after binding to EAK16-II and EAK16-IV, respectively, as determined by fluorescence quenching experiments on EAK-ODN mixture solutions. An ODN protection from Exonuclease 1 degradation is provided by the EAK16-II or EAK16-IV matrix when they are mixed with the ODNs at pH 4. However, the ODNs are protected to a much lower degree when the EAK-ODN aggregates are prepared at pH 7. The EAK-ODN aggregates prepared at pH 7 are found to dissociate more easily than those prepared at pH 4 when they are incubated with exonuclease I solution at pH 9.5. These results suggest that the ODN protection afforded by the EAK-ODN aggregates is correlated with their structural stability after being incubated with the nuclease solution. The stability of the EAK-ODN aggregates after dilution is determined by UV-Vis absorption. No detectable dissociation of the aggregates is observed over 20 hrs after a 5- and 10-fold dilution of the solution in the same buffer used for their preparation. The EAK-ODN aggregates remain stable after the solutions are centrifuged, and re-dissolved in fresh buffer solutions. The ability of an EAK matix to protect ODNs from nuclease degradation together with its biocompatibility and low-toxicity suggests that EAK self-assembling peptides could be used as carriers for gene delivery.
87

What individual characteristics influence commuting distance and mode transportation? : A quantitative case study of Malmö, Southern Sweden

Hägg, Erika January 2014 (has links)
How mobile people are affects the accessibility which can lead to several benefits like better match in the labour market and economical gain in the labour market. How mobile people are and their accessibility are effected by several factors. The purpose with this study is to see what individual characteristics that influences the choice of mode of transport when commuting and the travelled distance. This was done with a quantitative method that analyzed the Travel Survey of Southern Sweden. The result was carried out from descriptive result and regressions that was analysed. Findings from the result shows that gender, income and origin of birth are the individual characteristic that affects the choice of mode and travelled distance the most. The result can indicate that the commuting is also effected by structures as well as the economical incitement. The most used mode for transport and the probability to go by car increases with the economical gain does as well.
88

An analysis of crisis services accessibility of new Francophone arrivals in the city of Winnipeg

Buisse, Diane M.N. 13 October 2006 (has links)
Abstract The purpose of this practicum project was to facilitate access to mental health services and those health services that address issues causing emotional distress for new Francophone non English-speaking arrivals in the City of Winnipeg. The objectives were 1) to uncover Francophone mental health and specialized health resources in the city of Winnipeg, 2) to identify barriers, attitudes, and access issues pertaining to Francophone services, 3) to develop a directory of Francophone resources and links for health care professionals and other essential providers, and 4) to develop recommendations for future study and consideration. The project was implemented through telephone interviewing of 24 administrators and direct providers in 19 agencies that provided mental health and specialized health services, as well as refugee and immigration agencies. The study used qualitative methods and a semi-structured survey interview design. Via analysis of the results, the project presents an argument that language barriers are indeed preventing access to care for Francophone immigrants, refugees and international students in the City of Winnipeg. This was widely stated by participants from key organizations that work with this aggregate population on an occasional to a frequent basis. It is also evident that, with use of Bachrach’s Continuity of Care Dimensions/Principles, continuity of care for this population is equally compromised because of language barriers, lack of culturally sensitive providers, and lack of Francophone providers.
89

Age-Friendliness of the Urban Design Guidelines of the Cities of Kitchener and Waterloo

Bhupinder Preet, Kohli January 2014 (has links)
The fastest growing age group in Canada is seniors aged 65 years or older (Statistics Canada’s 2006 & 2007). The population of seniors is projected to increase to 6.7 million by 2021 and 9.2 million by 2041 (nearly one in every four Canadians) (Social Development Canada, 2006a; Statistics Canada, 2007b). Similarly, Population Estimates, Waterloo Region and Ontario, 2011 and Population Projections, Waterloo Region and Ontario, 2016, 2026 & 2036 (Region of Waterloo, 2012b, 2012c) indicate that the Region of Waterloo expects an increase in its senior population by 145.4% from year 2011 to 2036. Due to increased longevity and an increased percentage of older adults, this demographic shift poses challenges for communities, including increased healthcare costs and social isolation among seniors, which may threaten their active participation in the community. The research question ‘Do urban design guidelines of the Cities of Kitchener and Waterloo address the needs of an ageing population?’ motivates this study to examine the Urban Design Manuals of the Cities of Waterloo and Kitchener to determine the age-friendliness of the current urban design guidelines, and the role of the built environment in active ageing. The current urban design guidelines of the Cities of Kitchener and Waterloo are compared with the Design of Public Spaces Standards (Accessibility Standards for the Built Environment) by Accessibility for Ontarians with Disabilities Act, 2005 (AODA); the Universal Design Principles; key findings based on the literature review (Levine, 2003; Story, Mueller, & Mace, 1998); and analysed with in-depth knowledge gained through semi-structured interviews with seniors, planners, and focus groups. The participation of the seniors provided information on the gaps between what already exists and what is required. The key finding of the report is that the urban design guidelines of the Cities of Waterloo and Kitchener are fairly comprehensive in addressing the needs of seniors, but there is inadequate implementation of these guidelines.
90

KeySurf: a keyboard Web navigation system for persons with disabilities.

Spalteholz, Leonhard 23 April 2012 (has links)
For people with motor disabilities unable to control a pointing device, there is a need for an efficient keyboard Web navigation method. The current state of keyboard navigation tools is surveyed and discussed. The standard tab key navigation system is widely regarded as insufficient for practical keyboard access to the Web. Other techniques, such as identifier navigation --- where links are activated by entering their numeric code --- are found to be much more efficient, but possibilities remain for improvement. A technique based on selecting links by text search provides an alternative method of keyboard navigation, but does not minimize the number of required keyboard inputs, which is important for individuals not capable of fast typing input. A new technique called KeySurf is proposed, which aims to make text search navigation more efficient and intuitive by estimating which elements are more likely to be selected by the user, and then allowing those elements to be selected with fewer keystrokes. Web page elements without text associated with them are assigned labels based on algorithms that make generated labels predictable to the user. Various constraints on the searching algorithm are implemented to decrease the keystroke cost of selections, such as selecting visible elements first, matching the first characters of labels, and prioritizing visually prominent elements. In addition, the user's browsing history is used to calculate a measure of page and element interest in order to make interesting elements easier to select. KeySurf performance is examined in three experiments: an automated analysis of keystroke cost of element selection on randomly selected Web pages, a small study involving four individuals with motor disabilities to compare KeySurf and mouse use, and a study of 11 individuals browsing the Web with KeySurf collecting data passively in the background. The automated selection test calculates the number of keys necessary to activate each link for 48,182 links, resulting in a mean of 2.69 keystrokes. The study involving individuals with disabilities shows that KeySurf can be faster than mouse use if the user is able to type 2 or 3 keystrokes faster than pointing to a target using their pointing device. The study with 11 non-disabled individuals shows that for 4,601 recorded clicks, KeySurf would have required 2.38 keys per selection. Comparing mean keystroke cost for pages containing similar numbers of elements, we find that for real Web sessions KeySurf can decrease keystroke cost by 15\% compared to the simulation results by anticipating which elements a user is likely to select. A keystroke level model of tabbing, ID navigation, and KeySurf indicates that the predictability of ID navigation makes it more efficient for faster typists, while KeySurf is likely to be faster for slower typists. / Graduate

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