Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2006. / James Tsai, Committee Member ; John Leonard, Committee Member ; Karen Dixon, Committee Member ; Michael Meyer, Committee Member ; Randall Guensler, Committee Chair. Includes bibliographical references.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 54-56). Also available in electronic version.

Cette thèse se situe dans l'articulation entre les thématiques du transport et du développement durable, par le biais du concept de congruence. Elle aborde plus spécifiquement la question du rôle du chemin de fer dans l'amélioration de la vie des populations rurales et particulièrement dans deux états africains, le Mozambique et le Kenya. / This thesis is the relationship between the themes of transport and sustainable development through the concept of congruence. It specifically addresses the issue of the role of the railway in improving the lives of rural populations and particularly in two African states, Mozambique and Kenya.

This thesis examines issues surrounding route navigation. Emphasis is on the problems of elderly motorists. Elderly drivers have been said to avoid unfamiliar routes and may have wayfinding problems, but the extent and nature of these problems have not previously been investigated. This thesis aims to determine how drivers plan their routes and find their way in transit. It also seeks to investigate the prevalence and types of driver wayfinding problems, as well as their causes, consequences and psychological implications. Lastly, this thesis aims to measure the impact wayfinding problems have on mobility and identify potential solutions. Three studies were conducted, the first was a preliminary investigation into route navigation issues. Focus group discussions explored driver wayfinding strategies and problems. The second study consisted of a postal questionnaire survey of motorists. Results suggested the most common route planning method was to read a map and take notes of the route. For wayfinding on major roads, drivers stated a preference for road number, place name, and junction information. In cities, they requested information about street names, lane position and landmarks. More drivers under 60 years of age preferred landmark information than did elderly drivers. The most frequent wayfinding errors were: missing a road sign, choosing the wrong lane, and detecting a sign or a turn too late to respond safely. The most frequently reported causes of wayfinding errors were: insufficient, inaccurate, obscured or non-existent traffic signs; inattention or distraction; inaccurate directions; darkness; busy roads and road repairs. As hypothesised, elderly drivers reported more difficulties with wayfinding and this was related to reduced mobility. The third study explored different means of presenting route guidance information. An experiment was conducted to investigate the safety and efficiency of visual, auditory (speech) or a combined visual-auditory display. Driver performance, visual behaviour, subjective mental workload and preferences were recorded. For displaying simple route guidance information to drivers across ages, it is recommended that verbal displays be used as a primary source of guidance information and visual displays as a redundant reminder.

During the route discovery process, each node receiving the route request packet (RReq) will retransmit it exactly once. A distant neighbor may accidentally receive/loose the only RReq and use it to announce a new route, although that link is inferior/superior for route reply packets (RRep) or actual message routing. Overall, the constructed route may be far from the optimal. All existing route discovery schemes (including DSR/AODV) apply retransmission during route discovery exactly once (1R). Based on a realistic physical layer model, we propose two new route discovery schemes: n-retransmission (nR, retransmitting exactly n times) and n-retransmission c-reception (ncRR), retransmitting until we either reach a total of n own retransmissions or c copies from neighbors are heard. We compare our two new scheme with the traditional one, under otherwise identical conditions (same metric, same packet reception probability on each link) and the same choices about possibly retransmitting again upon discovering a better route (R+) or discarding it (R1), generating route reply packet for every received RRep (B*), or for first and better discovered routes only (B2), and retransmitting RRep exactly once (A1), up to a maximum of three times (A3), or optimally u times decided by link quality (Au). Experimental results show that the proposed ncRR scheme (for n=2 and c=3 or c=4) achieves the best tradeoff between quality of route, success rate and message overhead in the route discovery process, followed by the nR scheme, and both of them are superior to the existing traditional schemes.

In the Internet today, learnt prefixes are forwarded within autonomous systems (ASs) over internal Border Gateway Protocol (iBGP) sessions. Existing schemes for iBGP routing include the full-mesh (FM) solution, route reflection (RR) solution and confederation. Optimal prefix routing and route diversity are the main strength of the FM solution. However, it is rarely employed in a large networks due to its deficiency in aspects including scalability and large Routing Information Base (RIB) size requirement of routers. This is due to the fact that routers in this topology are required to peer with every other router within the AS. To combat these challenges, the RR scheme provides solution for scalability by decreasing the iBGP sessions requirement. Notwithstanding, the RR solution has its own challenges which includes reduced route diversity, introduction of divergence and forwarding anomalies. Also, the FM optimality may be lost since the Route Reflectors are responsible for reflecting the learnt prefixes to their corresponding clients based on its partial view of the network. The concept of Software Defined Networking (SDN) entails decoupling of the control plane from the forwarding plane such that the control plane is logically centralized benefiting from an overall knowledge of the network for decision making. In this work, we propose a solution based on multicasting which employs relay nodes in the iBGP message dissemination. Our solution brings session management scalability and minimization of duplicate prefix announcement through elimination of peer sessions deemed unnecessary. SDN controller is employed to configure and coordinate the multicast tree.

Recent newspaper headlines announced "Coastal plot prices up 500 per cent - SOUTHERN CAPE LAND SCRAMBLE" and reference was made to the big demand for plots at coastal resorts between Mossel Bay and Knynsa, and the holiday trade's interest in such big hotel deals as R400,000 at The Wilderness. ''Local authorities and businessmen feel the upsurge in demand for property, may indicate that the Southern Cape is set to take over "holiday mecca of the country". While the echo of these super cents in the till is deadening even the sound of the sea to some, other's concern is sending a chill down the spine. Many, during their active lives, craved for a slaver pace of living. Many found it here, and called it Hunter's Home, and Leisure Isle. Nov they see man's restlessness give a new scale to his pursuit of leisure.

Located in the Harbour of Cork, this work encourages the Harbour to turn back upon itself and re-establish the collective memory of transport by water. It was inspired by the Harbour Authority’s decision to introduce a passenger ferry network, servicing the City and the towns along the harbour. The meeting of the people and their harbour is to be finely nuanced through new installations, which facilitate the landing of these new vessels. Without these comprehensible points, which together create boundaries and act as threshold, the harbour is immense and continually shifting. These interventions intend to create a middle space between the landscape edge and the vast harbour: a type of ‘airlock’ which prepares the pedestrian for passage, using tools of sequencing and reframing to direct views. The project is investigated through mapping with an architecture that addresses the shifting scale along the harbour and a conversation begins between the macro and microcosm.

In the case of one car following another to a destination, it is very effective at getting the second vehicle to the destination quickly; however, the driver of the second car may not learn the route. Yet, for individuals, such as firefighters, law enforcement, and military personnel, it is imperative that a route be learned quickly and accurately and that an awareness of the situation is maintained while they traverse the given route. This leads to three questions, (a) will navigation aids affect initial route navigation; (b) will navigation aids affect retention; and (c) will navigation aids affect situation awareness while en route? The hypotheses of this study were that navigation aids would significantly increase the speed at which a person can initially navigate a route, but the use of the aids would significantly decrease the retention of the route navigated. The findings of this study support the hypotheses. The results suggest that participants that followed a confederate and participants that were given verbal directions were quicker and made fewer errors than participants that reviewed a map or initially figured the route out on their own (control group). The study also showed that as the participants navigated the route for a second time with no navigational assistance, the ones that reviewed a map or that were in the control group outperformed participants that initially had a confederate to follow or were given verbal directions their first time through. Finally, no real effects were found on the participants' situation awareness during the retention portion of the study.

Cycling for transport is an increasingly popular mode of travel in Hamilton, Ontario. Between 2011 and 2016, the mode share of cycling grew from 0.6% to 1.2%. As of 2019, 46% of the planned cycling facilities network has been built, which suggests that the city is transitioning to a cycling city. However, less is known about the built environment factors that influence cycling trips or the routes travelled by people who cycle in Hamilton. Drawing on the strengths of quantitative and qualitative methods, this research explores the built environment correlates of cycling and the perceptions of people who regularly cycle. First, a spatial interaction model was developed to test the level of cycling flows against various built environment attributes using trips data from the 2016 Transportation Tomorrow Survey. A novel feature of this analysis is the use of a cycle routing algorithm to infer routes as impedance factors. The most parsimonious model suggests that the shortest-path quietest routes best explain the pattern of travel by bicycle in Hamilton. To build upon these findings, objective built environment attributes were documented along select shortest-path quietest routes using environmental audits. The qualitative phase of the study then explores how well these approximated routes match where cyclists travel in Hamilton, as well as how the built environment more broadly in a growing city is perceived and experienced, by interviewing people who regularly travel by bicycle. The interviews highlight that the built environment is not yet bicycle-oriented and that cycling infrastructure influences mobility and route choice. As a result, people who cycle seek out routes that enable them to minimize interactions with cars, by incorporating quiet streets, and that have enjoyable environments. Policy implications and recommendations specific to these findings are discussed to further support the city of Hamilton’s transition to a more bikeable city. / Thesis / Master of Public Health (MPH)