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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.
51

"Community means the world to me" : an ethnographic study of a public house and bowling club

Glen, Ian J. January 2014 (has links)
This thesis is an ethnographic study of two local institutions within the community of Fallin which explores how twenty-four men understand, maintain and reproduce community and belonging. Throughout, the thesis suggests that the past acts as a stable reference point for the men to deal with social change. The Bowling Club and the Pub are suggested as being sanctuaries for this type of collective remembering to take place as they still reflect a mode of life associated with the past. It is argued that imagined histories were recollected, recreated and maintained through the power of storytelling and sharing experiences to the younger generations or outsiders (Blenkinsopp, 2012; Homans, 1974). This thesis suggests that perceived threats from outsiders only serve to further galvanise the central values of their community (Cohen, 1985; Homans, 1974). Chapter Two provides a review of the literature and theoretical concepts which sets out the academic foundations of this thesis. The work of Bourdieu shapes the theoretical, methodological and reflexive nature of this project. Chapter Three introduces the ethnographic method which gives this study an in-depth account of the narratives and identities of the men in this project. Chapter Four outlines the reflexive nature of the author’s relationship with the community, the Bowling Club and The Goth and how this affects the interpretations presented in this thesis. Chapter Five provides the reader with descriptive and demographic data of the community of Fallin and the research sites. Chapters Six and Seven analyse the data and directly answer the research question through interpreting interview data and using field notes. Concluding in Chapter Eight, this thesis suggests that the version of community that the men helped to reproduce and maintain is strongly associated with a historical working-class mode of life. This thesis suggests that these local institutions reproduce historical notions of community and belonging through outside forces and incomers challenging this traditional mode of life. Of particular interest is how the younger men in the study often adopt this shared habitus and learn how to be a man through regular interactions in The Goth and the Bowling Club.
52

Landscaping Practices, Environmental Ethics, and Sustainability in South Florida

Unknown Date (has links)
The research conducted for this thesis explores the link between environmental ethics and household landscaping practices. The central issue of any concept of sustainability is the incommensurability of various elements that define approaches, which is why it is treated here as a politicoethical process of subjective valuation. The ethics of sustainability were delineated according to major currents in environmental ethics, as well as briefly illustrated in the context of a broad discussion of climate change and resource availability, with some examples of strategies at different institutional levels. An online survey of 87 participants provided responses about local landscaping practices, environmental concerns, environmental ethics, and landscaping aesthetics at the household level. Quantitative analyses of the data yielded significant, but lowstrength correlations between environmentally sustainable landscaping practices and environmental ethics. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
53

Avaliação da eficiência e modelagem matemática da remoção de material particulado em canal gramado integrante de técnica compensatória construída em escala real

Felipe, Mayara Caroline 09 June 2014 (has links)
Made available in DSpace on 2016-06-02T20:00:58Z (GMT). No. of bitstreams: 1 6130.pdf: 2869136 bytes, checksum: 7b897b70a9098d8c22f48d18aeb83c6a (MD5) Previous issue date: 2014-06-09 / Financiadora de Estudos e Projetos / A math model was applied to describe the removal of particulate matter in lawn canal built in real scale. For this purpose different initial concentrations (Co) of particulate matter were investigated, as following: 65; 131; 196; 262 and 327 mg/L. The investigated rains, containing suspended solids, were discharged on the channel which has 100 m in length and slope of 2 %. Measurements were made of particulate material through the analysis of turbidity and total suspended solids (TSS) in 26 locations along the length of the channel. The experimental data were fit to the model using nonlinear regression parameter (kd) and (C*), which correspond to the decay kinetics constant and minimum limiting values the curve removal, respectively. Fractions removed and mathematical adjustment were assessed and performed for each isolated event and also for the result set. On average, the magnitude of the relative error ranged from 0.83% to 5.11%, with the highest average value obtained for the lowest concentration of particulate matter (65 mg L- 1). Regarding the values obtained for the decay constants (kd ), which represent the frequency of removal of particulate matter, it is noted that the same trends to a minimum value for the higher initial concentrations of particles (Co) . This fact indicates that the higher the initial concentration of particulate matter (Co), the greater the extent of travel required for its removal, with a maximum observed at around 80 m, for concentrations above 196 mg.L-1. / Neste trabalho, buscou-se avaliar e modelar matematicamente, por meio de modelo fenomenológico, a remoção de material particulado em canal gramado construído em escala real. Para tal, foram investigadas diferentes concentrações iniciais (Co) de material particulado: 65; 131; 196; 262 e 327 mg/L, os quais foram descarregados por meio de chuvas simuladas em canal de 100 m de extensão e declividade de 2%. As medidas de material particulado foram feitas por meio da turbidez e da análise de sólidos suspensos totais (SST), em 26 posições ao longo do comprimento do canal. Os dados experimentais foram ajustados ao modelo por meio de regressão não linear dos parâmetros (k) e (C*), os quais correspondem à constante cinética de decaimento e ao valor mínimo assintótico a curva de remoção, respectivamente. As frações removidas e o ajuste matemático foram avaliados e realizados para cada evento isolado e, também, para o conjunto de resultados. Em termos médios, o módulo do erro relativo variou entre 0,83% e 5,11%, sendo o maior valor médio obtido para a menor concentração de material particulado investigado (65 mg.L-1). Em relação aos valores obtidos para as constantes de decaimento (kd), as quais representam a frequência de remoção de material particulado, verifica-se que a mesma tende a um valor mínimo para as maiores concentrações iniciais de material particulado (Co). Tal fato indica que, quanto maior a concentração inicial de material particulado (Co), maior a extensão de percurso requerida para sua remoção, com limite máximo observado em torno de 80 m, para concentrações acima de 196 mg.L-1.
54

Evaluation of a robotic testing dashboard (RTD) used to compare autonomous robots with human pilots

Bergenholtz, Claes, Isacsson, John January 2021 (has links)
Autonomous robots are becoming a bigger part of our society. This thesis aims to evaluate a robot testing dashboard (RTD) that can be used as a new way of finding improvements when developing autonomous robots that do not use machine learning. The method that is used is design science research, which is used when creating and evaluating an artifact to address a practical problem. In our case the artifact isthe RTD. This project was performed at a company called Greenworks, which among other things develops and sells autonomous lawn mowers. The company wants to find new testing methods to help develop their autonomous lawnmowers. The RTD is created to visualize the inputs that the lawn mower utilizes to perform its tasks. A human pilot will then control the lawn mower, by only looking at that visualized data. If the pilot using the RTD can execute the same tasks as the lawn mower in its autonomous mode, the test results can be analyzed to see whether the human has done some parts of the tasks differently. The best outcome from the analysis of the test results is to find areas of improvement that can be implemented into the autonomous lawn mower design, both in software and hardware. For this purpose, an RTD was built and tested at Greenworks. From the tests using the RTD we concluded that it is helpful in the testing process, and we could find areas of improvements after analysis of our tests. However, the use of the RTD will require more time and resources compared to other methods. Each company that uses a similar dashboard concept will have to evaluate if the benefits are worth the time. Furthermore, the concept may not suit all areas of robotics but does seem to suit situations where a human can have an advantage over robots, such as in creative problem solving.
55

Object detection for a robotic lawn mower with neural network trained on automatically collected data

Sparr, Henrik January 2021 (has links)
Machine vision is hot research topic with findings being published at a high pace and more and more companies currently developing automated vehicles. Robotic lawn mowers are also increasing in popularity but most mowers still use relatively simple methods for cutting the lawn. No previous work has been published on machine learning networks that improved between cutting sessions by automatically collecting data and then used it for training. A data acquisition pipeline and neural network architecture that could help the mower in avoiding collision was therefor developed. Nine neural networks were tested of which a convolutional one reached the highest accuracy. The performance of the data acquisition routine and the networks show that it is possible to design a object detection model that improves between runs.
56

A Navigation Subsystem for an Autonomous Robot Lawn Mower

Hughes, Bradley Evan 19 September 2011 (has links)
No description available.
57

Avaliação da remoção de material particulado em canal raso gramado

Shinzato, Alexandre Hideki 10 April 2015 (has links)
Submitted by Izabel Franco (izabel-franco@ufscar.br) on 2016-09-27T14:11:10Z No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-03T19:41:52Z (GMT) No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-03T19:42:02Z (GMT) No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) / Made available in DSpace on 2016-10-03T19:50:38Z (GMT). No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) Previous issue date: 2015-04-10 / Não recebi financiamento / The study conducted examined the sediment removal behavior for a lawn channel built full-scale, 100 m in length, slope of 2% and wide base of 0.7 m in the Federal University of São Car them, San Carlos - SP. For this analysis, we simulated runoff for three volumes of downloads 5; 7; 10 m³, represented each with their respective hydrograph and blade height by passing the flood wave. These flows were mixed with the particulate material produced from the local ground of the campus area, sieved to smaller than 75 micron, which is used for varying the initial concentration for tests. The experimental data were fit to a model first order decay, Meira optimum slug flow in through non-linear regression using decay kinetic parameters (k d) and equilibrium concentration (C *). Fractions removed and the mathematical adjustment were evaluated and executed for each single event along the length of the lawn channel monitored in 26 positions. The peak of the hydrograph was investigated in the range of 11 ± 2 L / s and time base (tb) determined at the unloading point on the channel varied from 15, 25 and 35 minutes. The transit time in the channel (tT) was approximately 10.5 ± 2.5 m, corresponding to 0.14 ± speed 0,02 m / s. The maximum efficiency of particulate matter removing over the lawn channel length ranged from 47 to 81% in 20-90 m positions. Whereas all concentrations of investigates, it was found that for 15 minutes tB, the average maximum efficiencies were on the order of 64 ± 3% to ± 26 position of 31 m. TB to 25 minutes the average maximum were of the order of 73 ± 3% to 59 ± 24 m positions. Finally, for 35 minutes tB the average maximum efficiencies were obtained in the range of 65 ± 3% in the 73 ± 15 m positions. The ratio tb / tT correlated 0.98 with the position of maximum efficiency. The maximum removal positions are related to the decay constant (Kd). It was found that 70% of the values of the decay constant (Kd) is between 0.005 and 0.015 s-1, and to disregard the hydrograph represented by tB 15 minutes, 90% of the data is contained in it Halftone 0.005 Kd ≤ ≤ 0.015 s-1 and 85% in the range 0.007 ≤ 0.012 ≤ Kd s-1. It was identified direct and proportional relation of the equilibrium concentration (C *) and initial concentration (Co). / O estudo desenvolvido analisou o comportamento de remoção de sedimento para um canal gramado construído em escala real, 100m de extensão, declividade de 2% e largura de base de 0,7m, localizado na Universidade Federal de São Carlos, São Carlos - SP. Para tal análise, foram simulados escoamentos superficiais para três volumes de descarregamentos: 5; 7; 10m³, representados cada um com seu respectivo hidrograma e altura de lâmina pela passagem da onda de cheia. Estes escoamentos foram misturados com o material particulado produzido a partir do solo local da região do campus, peneirado para dimensões menores que 75μm, o qual foi utilizado para variação da concentração inicial para os ensaios realizados. Os dados experimentais foram ajustados a um modelo de decaimento de primeira ordem, em escoamento ideal pistonado por meio de regressão não linear, usando os parâmetros cinéticos de decaimento (kd) e de concentração de equilíbrio (C*). As frações removidas e o ajuste matemático foram avaliados e realizados para cada evento isolado, ao longo do comprimento do canal gramado e monitorados em 26 posições. O pico dos hidrogramas investigados foi da ordem de 11±2L/s, e o tempo de base (tB) determinado no ponto de descarregamento no canal variou de 15, 25 e 35 minutos. O tempo de trânsito no canal (tT) foi da ordem de 10,5±2,5 minutos, correspondente à velocidade de 0,14±0,02m/s. A eficiência máxima de remoção de material particulado ao longo do comprimento do canal gramado variou de 47 a 81% em posições de 20 a 90m. Considerando todas as concentrações investigadas, verificou-se que para tB de 15 minutos, a média das máximas eficiências foram da ordem de 64±3% para posição de 31±26m. Para tB de 25 minutos a média das máximas foram da ordem de 73±3% para posições de 59±24m. Finalmente, para tB de 35 minutos a média das máximas eficiências obtidas foram da ordem de 65±3% nas posições de 73±15m. O quociente tB/tT apresentaram correlação de 0,98 com a posição de máxima eficiência. As posições de máxima remoção estão relacionadas à constante de decaimento (kd). Verificou-se que 70% dos valores da constante de decaimento (kd) estão entre 0,005 e 0,015 s-1, sendo que ao desconsiderar o hidrograma representado por tB de 15 minutos, 90% dos dados estão contidos no intervalo 0,005 ≤ kd ≤ 0,015s-1 e 85% no intervalo 0,007 ≤ kd ≤ 0,012s-1. Foi identificada relação direta e proporcional da concentração de equilíbrio (C*) e concentrações iniciais (Co).
58

Thermal Performance of Various Roof Elements Under Different Weather Conditions

Joshi, Vijesh Vasanth January 2015 (has links) (PDF)
Beside the point of whether the country is developed or underdeveloped, energy crisis is a common scene all over the world. In order to balance energy supply and demand, either one has to increase the supply or decrease the demand. The latter seems to be the better choice since we have limited sources of energy. About 20% - 40% of energy produced by a country is being consumed by HVACs in buildings. Hence much e ort is towards energy conservation in buildings. Around 30% of the building energy consumption in India is due to cooling load. Previous studies have shown that around 60% of the heat due to solar radiation enters through the roof of the building. The present work aims to reduce the heat load entering through the roof by coming up with a better roofing technique for moderate climatic regions. In the present work, enclosures with the side walls and the floor (bottom slab) insulated has been studied both numerically and experimentally. Heat transfer between the ambient and enclosure is only through the roof (top slab). Six common roofing types have been studied in this thesis. Reinforced cement concrete (RCC) roof Mangalore tile roof Thatched roof GI Sheet roof and Concrete roof with lawn (green roof) Concrete roof with a layer of wet sand The experimental studies have been carried out to understand heat transfer through these roofs. A comparative study of all six types of roofs has been done. Apart from this, the effect of a shade net on room models with bare RCC roof and GI sheet roof is also studied and presented in this thesis. Each enclosure has a height of 0.3m and the sides are 1m in size. Mangalore tile and thatched roofs are inclined to the horizontal. To understand the heat flow process, the temperature variations of different surfaces and enclosure air, and, air temperatures near the top and bottom slabs were recorded. In addition, weather conditions such as solar radiation, ambient air temperature, and wind speed are recorded. The details of the experimental set up are given in chapter 3. In chapter 2, a mathematical model to determine the temperature variations in the enclosure is given. All the three modes of heat transfer (conduction, convection and radiation) are present and the system is unsteady. The objective is to find the temperatures of the walls and the enclosure air temperature. Heat flows either from surroundings to the enclosure or from enclosure to the surroundings through the walls of the enclosure. As the solar radiation data is known for a given location, un-steady heat conduction equation is solved for the walls of the enclosure with heat flux boundary conditions to solve for the temperatures. Standard correlations have been used for calculating the convective heat transfer to the ambient and in the enclosure. Most importantly, the experiments conducted were field experiments. The main objective of the study had been to understand the effect of roof on thermal comfort conditions inside the scaled model rooms under five different weather conditions which are commonly observed in warm tropics: (1)summer, (2)winter, (3)cloudy, (4)unsteady, and, (5)rainy. The details of weather conditions have been discussed in chapter 4. In the present analysis, various issues were looked upon such as, temperature values, time lag, thermo-physical properties of the roof material, weather conditions, average over a 24 hours cycle etc. For the comparative analysis, bare RCC roof has been assumed to the base case as most of the buildings are built with RCC roof (for example, in India, around 29% of the buildings have RCC roof, as per 2011 census). On one side we have passive cooling techniques (lawn over RCC roof and wet sand over RCC roof), and, on the other side we have breathing roofs (Mangalore tile roof and thatched roof). Apart from these, the GI sheet roof is commonly used for small scale industries and residential houses. It has been observed that the concrete roof with lawn (hereafter called as lawn over RCC roof ) being the best one among the considered six roofs. Having lawn over RCC roof could result reduction in both solar gain and the diurnal variation of enclosure inside temperatures. The range of temperature variation was least disturbed due to change in weather conditions. In the case of wet sand over RCC roof, the diurnal variations of enclosure inside temperatures were relatively higher as compared with those in the lawn over RCC roof case. As far as breathing roofs are concerned, the two were found to be better than bare RCC roof with thermal comfort as point of view. On the other hand, breathing effects are found to be better in case of Mangalore tile roof than in case of thatched roof. GI sheet roof was found to be the worst among considered for thermal comfort. The effect of using shade net over RCC and GI sheet roof proves to have good potential to reduce cooling load with negligible adverse effects during night time. Detailed discussion of results has been done in chapter 4. Numerical simulations have been carried out for the case of model room with bare RCC roof. A comparative analysis of both experimental and numerical results has been discussed in chapter 5. The important conclusions are discussed in chapter 6.
59

Akumulátorová sekačka na trávu / Battery supplied lawn mower

Picmaus, Jan January 2021 (has links)
The thesis deals with a concept of turning a conventional petrol powered lawn mower to a battery powered solution which is powered by lithium cells. A division to three chapters, comparison, mechanical and electrical, provides fluency of the whole design and further realization. The arrangement of chapters is performed so that the continuity of the thesis is maintained. Calculations of parameters of every motor and transmission with choosing particular devices are just a part of much interesting information which can be found in this thesis. All new components have full documentation except those which were changed during manufacturing. The electrical part explains every part of the schematics in detail. The realization contains difference between preliminary design and further production, manufacturing of the PCB and powering up the motor drives. The last part of the thesis contains temperature measurements of the device at no load.
60

Improving the diagnostic process for robotic lawnmowers : After-sales efficiency benefits from an Experimental Diagnostic Tool

Appelberg, John, Andersson, Adam January 2022 (has links)
An Experimental Diagnostic Tool (EDT) was developed to increase the efficiency of the diagnostic process of robotic lawn mowers which resulted in a 200% productivity increase when utilizing a proposed formula specifically designed for the diagnostic process of robotic lawn mowers. The tool does not only extract and process data from the robotic lawn mower wirelessly but also highlights potential faults through an intuitive and easy-to-use interface - empowering servicing technicians who perform the diagnostics to perform at a higher level. Further, efficiency is a term widely used in various domains and contexts when measuring the capacity of a process. Proposed general definitions of the term have been given by previous authors and researchers. However, due to a lack of universally set definitions which fit all situations, the term remains ambiguous when improvements to a specific process are needed. The unclear definition is due to the variations within each process affecting the definition of both the term itself, but also similar terms fundamentally connected to it such as productivity, performance, and profitability. The following report contains an investigation of exploratory research where the understanding of efficiency and its related concepts are analyzed within the after-sales diagnostic process of robotic lawn mowers.

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