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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.
271

Evaluating LoRaWAN for IoT applications by developing a wireless parking space monitoring sensor

Jontegen, Felix, Good, Emma January 2018 (has links)
The process of finding a parking space can be a tedious task that drivers spent too much time on today. With the rising threat from global warming, reducing the time spent driving is vital. The purpose of this thesis is to evaluate the use of LoRaWAN for urban IoT applications by developing a sensor system for parking space monitoring to make this process easier. The main component of the developed prototype of the sensor system consists of a The Things UNO, which is a modified version of the Arduino Leonardo with an integrated RN2483 LoRaWAN transceiver module. Two types of sensors, an ultrasonic distance sensor and a magnetometer, were tested for car detecting abilities in the sensor system. The distance sensor was proven to be the more reliable sensor for detecting cars, but a combination of both a distance sensor and a magnetometer can be used to improve the power usage of the system. LoRaWAN has a high potential to work great in a parking space monitoring system and other urban IoT applications, but its coverage and reliability in different conditions requires more testing. / Att hitta en parkeringsplats kan vara en omständing uppgift, och är något som bilister idag spenderar för mycket tid på. Med den ökade risken från global uppvärmning är det viktigt att försöka reducera körtid. Syftet med den här rapporten är att utvärdera användandet av LoRaWAN för urbana IoT-applikationer genom att utveckla ett sensorsystem för att bevaka parkeringsplatser för att göra det enklare att hitta lediga parkeringsplatser. Huvudkomponenten i den utvecklade prototypen av sensorsystemet är en TheThings UNO, vilket är en modifierad version av en Arduino Leonardo med en inbyggd RN2483 LoRaWAN-modul. Två sorters sensorer, en avståndssensor och en magnetometer, testades i sensorsystemet. Avståndssensorn visade sig vara den mer pålitliga sensorn för att detektera bilar. En kombination av en avståndssensor och en magnetometer kan poteniellt användas tillsammans för att minska strömanvändningen. LoRaWANhar stor potential att fungera i ett parkeringbevakningssystem samt andra urbana IoT-applikationer, men dess täcking och pålitlighet i olika miljöer borde undersökas mer.
272

Bike-and-ride in a suburban environment : An analysis of methods to increase bike-and-ride in Knivsta / Bike-and-ride i ett förortsmiljö : En analys av metoder för att öka bike-and-ride i Knivsta

Magnadóttir, Helga January 2019 (has links)
When striving to develop towards sustainability, reducing private car use is a crucial factor. The most convenient alternative is to replace the private car with public transport. Fast public transport types, such as trains, have large catchment areas, thus walking to the station can be time consuming and increases door-to-door travel time compared with the private car. An alternative to this is bike-and-ride, i.e. cycling to the transit station and continuing with public transport. This study aims to find ways to increase public transport use, focusing on cycling between the home and the transit station. This is done through a literature study and a case study in Knivsta, a suburban area of Stockholm connected to the city center through commuter trains. Improvements in the current bike-and-ride infrastructure in Knivsta are suggested, using the principles of Transit Oriented Development and Theory of Planned Behavior as guidelines. The most important aspects of high bike-and-ride proportions is the provision of separate bicycle paths and plentiful high-quality bicycle parking at transit stations. The current situation in Knivsta is inadequate with few separate bicycle paths and the bicycle parking does not fulfil recommendations. Suggestions for improvements are proposed, with developing a regional bicycle highway network in addition to other bicycle paths throughout the town of Knivsta, in addition to increased and improved bicycle parking at Knivsta train station to fulfil the requirements of the future as Knivsta is expected to double in population towards 2030. The changes proposed to the bicycle infrastructure in Knivsta have potential to increase public transport use, decreasing private car and park-and-ride use. Due to the bicycle network being convenient and accessible for virtually everyone, the municipality will develop towards environmental, economic, and social sustainability.
273

Safety Assessment of Different Bike Infrastructure Types: A Data-Driven Approach / SAFETY ASSESSMENT OF DIFFERENT BIKE INFRASTRUCTURE TYPES

Imad Monzer, Yasmina January 2023 (has links)
This thesis comprises two studies that investigated bike infrastructure safety in North America. The first study conducted a corridor-level analysis to quantify the safety of different bike infrastructure types and assess the influence of corridor-specific characteristics on their performance. Using a Poisson-lognormal Full Bayesian model, the study analyzed fatal and injury bike-vehicle collisions on over 7800 corridors in Toronto, Canada. The findings revealed that bike infrastructure effectively reduces bike collisions, with cycle tracks demonstrating superior safety benefits due to the physical separation of cyclists from vehicular traffic. Cycle tracks were found to be particularly effective on long corridors with fewer intersections as bike-vehicle interactions along the corridor are minimized. Signed routes were safe on low-volume and low-speed roads, while bike lanes are more suited for a short section of high-volume corridors with a high intersection density. The second study assessed the safety of parking-protected bike lanes (PPBL), a new concept that is rapidly growing in North America. Utilizing data from nineteen street sections in Vancouver and Ottawa, the study developed a Full Bayesian Before-and-after model to evaluate the safety impacts of converting traditional painted bike lanes to PPBLs. The results indicated a significant reduction of 31.2% in total collisions after PPBL implementation. However, the effects of PPBLs on cyclist safety were found to be sensitive to factors such as bike path opening density, intersection density, and intersection treatments. In roads where proper intersection treatments and minimal protection of PPBL openings can be provided, painted bike lanes can be converted into PPBLs, and significant safety benefits can be expected. The findings of this thesis offer practical guidance for city planners and policymakers regarding the safety implications of different bike infrastructure types and the most appropriate conditions to implement them, which supports bike safety enhancement initiatives and attracts more people to bike. / Thesis / Master of Applied Science (MASc) / This thesis presents two studies that offer valuable insights to improve bike safety. The first study examined the safety of various bike infrastructure types along with the impact of corridor characteristics on their performance. The findings emphasized the effectiveness of cycle tracks in reducing collisions on long corridors with fewer intersections. Signed routes were found to be effective on low-volume and low-speed roads, while bike lanes were ideal on short sections of high-volume roads with a high intersection density. The second study assessed the impacts of new designed concept, known as the parking-protected bike lanes (PPBLs). The study showed that converting painted bike lanes to PPBLs significantly reduced total collisions. However, proper treatment of intersection and bikeway openings is crucial for enhancing cyclist safety and reducing multi-vehicle rear-end collisions. Where proper intersection treatment and minimal protection of bikeway openings can be provided, bike lanes can be safely converted into PPBLs.
274

City of Los Angeles Cornfield Arroyo Seco Specific Plan: Parking Management Strategies

Thompson, Miriam L 01 June 2013 (has links) (PDF)
This study examines the state of off-street parking in the Cornfield Arroyo Seco Specific Plan (CASP) area of the City of Los Angeles. The focus is on discovering relevant strategies to strengthen the plans ability to reduce parking supply and demand. Research has shown a causal relationship between planning policies and the oversupply of parking. An auto-centric approach to land use and urban form creates societal problems such as traffic congestion, air pollution, inflated development costs, and hostile pedestrian landscapes. Further issues that are directly associated with parking include: poor water quality, neighborhood livability, and ambient temperature. Additionally, an overabundance of parking supports increased vehicle miles traveled which is a major source of greenhouse gases. The imbalance between parking supply and demand in the City of Los Angeles has resulted in large tracts of land that are paved over by parking lots instead of more valuable land uses. A thorough assessment of the opportunities to improve the state of parking in the Los Angeles CASP area is needed. The (qualitative) research consisted of a review of secondary data such as the Los Angeles General Plan, the Los Angeles Municipal Code (LAMC), the best practices of Pasadena, Santa Monica and an exposé of scholarly parking theory. The primary (quantitative) data collection methods in this study comprised an aerial survey and a field survey. The results show that half of the major land uses in the area never reach optimal occupancy. A careful evaluation of the CASP revealed that it does institute several progressive parking policies that are more stringent than the LAMC, namely being the first plan in the city that does not include parking requirements. However there are a number of relevant parking management strategies which could serve to further strengthen the CASP. The Specific Plan does not mandate employers to provide transit passes or parking cash-outs. Providing Eco Passes can yield benefits for developers, property owners, employers, commuters, transit agencies, and cities. Another way to reduce parking demand and parking requirements is to offer commuters the option to “cash out” their employer-paid parking. Both transit passes and parking cash-out are cost effective because it is much cheaper to pay for a transit ride to and from work than to pay for a free parking space at work. These two strategies have potential to add another dimension to demand management, civic viability and contribute to the paradigm shift that is needed to mitigate our environmental impact.
275

Analysis of Charging Patterns of Electric Vehicles, Case Study in Uppsala, Sweden.

Yousef, Ahmed January 2022 (has links)
Electric vehicles (EVs) are used instead of fossil fuel-burning vehicles to reduce greenhouse gases. The increased rate of utilizing EVs has an impact on the electric power system. This is due to the fact that EVs are loads that increase the peak demand. From these perspectives, this thesis studies the load of the electric chargers in a parking house in Uppsala and studies the effect of adding battery storage systems. The cost of used electricity is also calculated at different battery storage system (BSS) capacities, and the electricity bill is evaluated at these different conditions.  The data used in this work was collected from a parking house allocated in Uppsala city in 2021. It is equipped with 30 charging stations and 60 charging points in total. In addition, the parking house is connected to a PV system with two racks of batteries with a capacity of 137kWh. The surplus power generated by the PV system is sold to the grid. The data from the PV production and EVs demand is analyzed using MATLAB. The electricity price used in this study is from a standard contract from Vattenfall, with different prices at day and night (0.144 SEK/kWh at night and 0.48 SEK/kWh during day time). The battery is charged during the night, at a lower price, and discharges during the day. The excess power from the PV is also stored in the battery as self-consumption is more profitable than selling it to the grid.  The results show that the installed BSS units reduce the overall cost of the load as compared to those without BSS units. By studying the system under different battery capacities, the electricity bill is reduced to a certain limit. However, the increase in storage capacity beyond 137 kWh has no effect on the overall electricity cost. This maximum limit of the BSS unit's capacity would be greatly affected by the size of the installed PV system and the number of EVs to be charged. Controlling the charging and discharging periods has a significant impact on reducing the system cost.
276

Towards a sustainable mobility paradigm? An assessment of three policy measures

Johansson, Fredrik January 2019 (has links)
Transportation and mobility are important components in the organisation and structure of people´s daily activities, but the transport sector has considerable environmental impacts, e.g. greenhouse gas emissions and land use. Governance of the sector is difficult, as there is an ongoing a shift in governance structures away from hierarchical towards more collaborative governance. Given these challenges, it may be necessary to shift the focus from mobility to accessibility and to adopt a new paradigm in transport planning. This thesis critically investigates what a paradigm shift might mean for the Swedish national and municipal transport, housing and parking planning context and examines what a Social Practice Theory framework could contribute in analysing such a paradigm shift. This is done by investigating three different policies that are arguably in line with a shift in planning paradigms. All three policy measures open up decision making to different stakeholders or even citizens, reflecting a shift in governance, and all highlight the need to shift the focus from physical infrastructure to accessibility, through collaboration with a range of stakeholders. However, in each case, current conditions and practices render a transition more difficult. The Swedish Transport Administration (STA) states the importance of reducing the need to travel and of using existing infrastructure more efficiently, and stipulates that these types of measures should be considered before new infrastructure investments. However, the STA has a limited mandate to finance these measures, resulting in ambiguous signals and frustration among regional STA officials. This thesis shows that making the STA’s mandate more function-oriented would facilitate a transition in line with the sustainable mobility paradigm. Another policy measure discussed in the thesis is a shift from minimum parking requirements, where developers are required to build a minimum number of parking spaces, to flexible parking requirements, where the number of parking spaces provided depends on the local context and where other mobility services may replace the need for physical parking spaces. In this thesis, people who have bought apartments in developments with flexible parking requirements were surveyed in order to understand their practices and how they perceive and plan to use the mobility services provided. The feasibility of using a new parking management tool, Parking Benefit Districts, in a European context (Stockholm, Sweden) was assessed. In a Parking Benefit Districts system, parking charges are implemented, increased or extended to curb parking, with the revenues being returned to the area where the charges are imposed and with citizens, or other stakeholders, participating in decisions on how to use the revenues. The underlying intention is to increase acceptance of parking charges, as on-street parking charges may be deemed necessary by planners, but are unpopular among citizens and other stakeholders. This thesis shows that there are no legal barriers to implementing a Parking Benefit District programme in Sweden, but there are some limitations on how revenues can be used. Moreover, Sweden does not have this planning tradition and the programme may not be perceived as legitimate. Another important issue is equity and participation, e.g. it is important to consider who to include and how to include them. Overall, the policy measures studied involve a shift away from an infrastructure-centred to a people-centred approach. However, other planning practices and institutions may push in different directions. This thesis shows that a Social Practice Theory framework can be useful as a lens through which researchers and policymakers view possible changes needed to achieve a sustainable mobility paradigm. / Transport och mobilitet är viktiga komponenter i organiseringen och strukturen av människors dagliga aktiviteter. Transportsektorn ger emellertid upphov till stor miljöpåverkan, exempelvis växthusgasutsläpp och markanvändning. Governance av sektorn är komplicerad och det har skett ett skifte från en hierarkisk styrning mot en större delaktighet och samarbete mellan olika aktörer. Givet dessa utmaningar kan det finnas behov av att flytta fokus från att palnera för rörlighet till tillgänglighet samt att ändra planeringsparadigmer. Syftet med avhandlingen är dels att kritiskt undersöka vad ett paradigmskifte skulle kunna innebära i det svenska nationella och kommunala transport-, bostads- och parkeringsplaneringssammanhanget, dels att undersöka hur ett Social Practice Theory ramverk skulle kunna bidra till förståelsen av ett sådant paradigmskifte. För att göra detta har avhandlingen undersökt tre policys som är i linje med ett paradigmskifte. Alla policys som diskuteras i avhandlingen öppnar upp beslutsfattande för olika aktörer eller medborgare. Vidare lyfter alla diskuterade strategier fram behovet av att flytta fokus från fysisk infrastruktur till tillgänglighet och att samarbete mellan olika intressenter är nödvändigt. I varje fall finns dock förhållanden och praktiker som försvårar omställningen. Trafikverket framhåller exempelvis vikten av att minska behovet av att resa och av att använda befintlig infrastruktur mer effektivt, och de menar att dessa åtgärder bör övervägas innan nya infrastrukturinvesteringar. Samtidigt har Trafikverket begränsat mandat att finansiera dessa åtgärder, vilket ger upphov till tvetydiga signaler och frustration bland regionala planerare på Trafikverket. Papper I argumenterar för att ett mer funktionsorienterat mandat skulle kunna underlätta en ett paradigmskifte i linje med en ’sustainable mobility paradigm’. I paper II diskuteras en förändring från miniminorm för parkeringsplatser vid bostäder, där byggherrarna måste bygga minst ett visst antal parkeringsplatser, till flexibla parkeringstal, där antal parkeringsplatser som ska byggas beror på den lokala kontexten och där andra mobilitetstjänster kan ersätta behovet av parkeringsplatser. I detta paper studeras personer som har köpt lägenheter i flerbostadshus med flexibla parkeringstal. Målet är att förstå dessa människors praktiker och hur de använder och uppfattar de mobilitetstjänster som tillhandahålls. I papper III diskuteras möjligheten att använda ett nytt parkeringsverktyg, Parking Benefit Districts, i en europeisk kontext. Parkering Benefit Districts är ett koncept där parkeringsavgifter på gatan införs, höjs eller utökas. Intäkterna från parkeringsavgifterna återförs därefter till det område där de togs ut, och medborgare, eller andra intressenter i området, deltar sedan i beslutet om hur intäkterna ska användas. Syftet med denna åtgärd har traditionellt varit att öka acceptansen för parkeringsavgifter, eftersom parkeringsavgifter på gatan kan anses vara fördelaktiga av planerare, men impopulära bland medborgare och andra intressenter. Paper III nämner i analysen att det inte finns några legala hinder för att genomföra ett Parking Benefit District program i Sverige, men det finns vissa begränsningar för hur intäkterna kan användas. Planerare i Stockholms stad hävdar dock att Sverige inte har den här planeringstraditionen och påpekar att ett sådant åtgärd kanske inte uppfattas som legitim. En annan viktig fråga att diskutera är jämlikhet och deltagande. Det finns en risk att vissa grupper i samhället inte deltar i samma utsträckning och det är därför viktigt att överväga vem som ska involveras samt hur det ska ske. I slutet diskuteras resultaten i relation till forskningsfrågorna. Alla de studerade policys skiftar fokus från fysisk infrastruktur till människors behov. Samtidigt finns det andra planerings praktiker och institutioner som drar samhällsutvecklingen i motsatt riktning. I avhandlingen diskuteras även hur ett Social Practice ramverk kan hjälpa både forskare och beslutsfattare att se de förändringar som behövs för att nå en ’sustainable mobility paradigm’. / <p>QC 20181228</p>
277

Reimagining Streets through the Autonomous Car

Chambard, Agustin Andres 13 July 2023 (has links)
The widespread adoption of autonomous cars has the potential to revolutionize urban transportation, but what impact will it have on urban form? This thesis examines the hypothesis that adopting autonomous cars can transform street space into a more human-centric purpose, leading to more livable and sustainable cities. The research was conducted through a literature review, analysis of case studies, and the development of specific street designs in order to reveal possible scenarios. The literature review suggests that adopting autonomous cars can reduce the need for parking and increase the efficiency of transportation. Furthermore, the rise of shared cars is expected to revolutionize the way people move. With the advent of autonomous cars, it is possible that personal cars will become less necessary as people can rely on these constant-moving vehicles for transportation. These changes will impact our cities creating new opportunities to improve the urban space. The thesis explores these challenges and opportunities through design for the actual urban environment of Washington D.C. As the capital of the United States, the country where cars have significantly shaped its cities, it is also home to influential political and policy-makers. As a result, the city offers a good opportunity to rethink the future urban environment when this technology will be widely adopted. The findings of this thesis suggest that the adoption of autonomous cars has the potential to transform urban form reclaiming street space for people, but also requires careful planning and design to ensure that the benefits are distributed equitably and the negative impacts are minimized. The thesis concludes with four street proposals, each performing a different role in the city and the results provoke a reflection of the role of the street in our cities. / Master of Science / The widespread use of self-driving cars can transform our lives in cities. This new technology could lead to a more human-centered urban environment, where streets are designed for people rather than cars. The use of self-driving cars could also reduce the need for parking and improve the efficiency of transportation. However, this transformation requires careful planning and design to ensure that the benefits are distributed fairly and that negative impacts are minimized. A recent study looked at the potential impact of self-driving cars in Washington D.C., and suggests that the adoption of this technology could transform urban form and make cities more livable and sustainable. The study concludes with several street design proposals that could help shape the future of our cities. The findings of this thesis suggest that the adoption of autonomous cars has the potential to transform urban form reclaiming street space for people, it concludes with street proposals, each performing a different role in the city.
278

Crack Propagation Analysis of a Pre-stressed L-shaped Spandrel Parking Garage Beam

Hashtroodi, Seyedowjan January 2014 (has links)
No description available.
279

Development of Storage and Retrieval Algorithms for Automated Parking Systems

Dou, Chao 17 July 2012 (has links)
No description available.
280

APPROACHING URBAN SUSTAINABILITY THROUGH RESTORATION ECOLOGY AND GREEN INFRASTRUCTURE / NATIVE PLANT PERFORMANCE ON A RIPARIAN BUFFER RESTORATION AND FEASIBILITY OF A CONSTRUCTED WETLAND AT AN URBAN PARKING LOT

Matties, Reyna 17 November 2017 (has links)
Most cities are dominated by asphalt and concrete, which blocks the natural movement of rain water. Wetlands, riparian buffers, and roadsides are being lost or degraded in urban areas due to human development. Cities can be designed to benefit humans and nature by using techniques from green infrastructure and restoration ecology to improve urban sustainability. Parking lot M on McMaster University's west campus, constructed in 1968 on a former floodplain, directs the highly saline parking lot runoff into the adjacent Ancaster Creek. Natural groundwater sources along the surrounding hillslopes are directed into pipes under the parking lot and into the creek. A one-hectare riparian buffer restoration at lot M was used to assess the viability of depaving asphalt and establishing native plants through a vegetation study. Total native plant biomass was found to be similar to non-native plant biomass and was affected by road-salt salinity from the parking lot. Species richness per quadrat was higher for non-native plants, and greater for both non-native and native plants where less salt was present. Key hydrological fluxes were examined at the parking lot that could contribute to a proposed 0.6 hectare constructed wetland on the parking lot, known as “McMarsh.” Potential wetland water storage is in surplus year round, with an average storage of 265 mm/month. Successful restorations require maintenance following the establishment of native species. Management and maintenance of the restoration can help decrease non-native species. Engaging with the community through outreach and education on restoration projects is important for a successful restoration and increasing urban sustainability in cities. / Thesis / Master of Science (MSc) / Most cities are dominated by asphalt and concrete, which blocks the natural movement of rain water. Wetlands, riparian buffers, and roadsides are being lost or degraded in urban areas due to human development. Cities can be designed to benefit humans and nature by using techniques from green infrastructure and restoration ecology to improve urban sustainability. Parking lot M on McMaster University's west campus, constructed in 1968 on a former floodplain, directs the highly saline parking lot runoff into the adjacent Ancaster Creek. Natural groundwater sources along the surrounding hillslopes are directed into pipes under the parking lot and into the creek. A one-hectare riparian buffer restoration at lot M was used to assess the viability of depaving asphalt and establishing native plants through a vegetation study. Total native plant biomass was found to be similar to non-native plant biomass and was affected by road-salt salinity from the parking lot. Species richness per quadrat was higher for non-native plants, and greater for both non-native and native plants where less salt was present. Key hydrological fluxes were examined at the parking lot that could contribute to a proposed 0.6 hectare constructed wetland on the parking lot, known as “McMarsh.” Potential wetland water storage is in surplus year round, with an average storage of 265 mm/month. Successful restorations require maintenance following the establishment of native species. Management and maintenance of the restoration can help decrease non-native species. Engaging with the community through outreach and education on restoration projects is important for a successful restoration and increasing urban sustainability in cities.

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