Global ETD Search

281	Modeling, Control, and Design Study of Balanced Pneumatic Suspension for Improved Roll Stability in Heavy Trucks Chen, Yang 03 May 2017 (has links) This research investigates a novel arrangement to pneumatic suspensions that are commonly used in heavy trucks, toward providing a dynamically balanced system that resists body roll and provides added roll stability to the vehicle. The new suspension, referred to as "balanced suspension," is implemented by retrofitting a conventional pneumatic suspension with two leveling valves and a symmetric plumbing arrangement to provide a balanced airflow and air pressure in the airsprings. This new design contributes to a balanced force distribution among the axles, which enables the suspension to maintain the body in a leveled position both statically and dynamically. This is in contrast to conventional heavy truck pneumatic suspensions that are mainly adjusted quasi-statically to level the body in response to load variations. The main objectives of the research are to discover and analyze the effects of various pneumatic components on the suspension dynamic response and numerically study the benefits of the pneumatically balanced suspension system. A pneumatic suspension model is established to capture the details of airsprings, leveling valves, check valves, pipes, and air tank based on the laws of fluid mechanics and thermodynamics. Experiments are designed and conducted to help determine and verify the modeling parameters and components. Co-simulation technique is applied to establish a multi-domain model that couples highly non-linear fluid dynamics of the pneumatic suspension with complex multi-body dynamics of an articulated vehicle. The model is used to extensively study effects of pneumatic balanced control of the suspensions on the tractor and trailer combination dynamics. The simulations indicate that the dual leveling valve arrangement of the balanced suspension provides better adjustments to the body roll by charging the airsprings on the jounce side, while purging air from the rebound side. Such an adjustment allows maintaining a larger difference in suspension force from side to side, which resists the vehicle sway and levels the truck body during cornering. Additionally, the balanced suspension better equalizes the front and rear drive axle air pressures, for a better dynamic load sharing and pitch control. It is evident from the simulation results that the balanced suspension increases roll stiffness without affecting vertical stiffness, and thereby it can serve as an anti-roll bar that results in a more stable body roll during steering maneuvers. Moreover, the Failure Mode and Effects Analysis (FMEA) study suggests that when one side of the balanced suspension fails, the other side acts to compensate for the failure. On the other hand, if the trailer is also equipped with dual leveling valves, such an arrangement will bring an additional stabilizing effect to the vehicle in case of the tractor suspension failure. The overall research results presented show that significant improvements on vehicle roll dynamics and suspension dynamic responsiveness can be achieved from the balanced suspension system. / PHD Pneumatic suspension heavy truck multi-domain modeling co-simulation roll stability balanced suspension
282	"No peito e na raça" - a construção da vulnerabilidade de caminhoneiros. Um estudo antropológico de políticas públicas para HIV/AIDS no Sul do Brasil / "The long haul" - The construction of truck drivers vulnerability. An anthropological study of HIV/AIDS public policy in the South of Brazil. Leal, Andrea F. 05 May 2008 (has links) The main goal of this study, in the field of the Anthropology of Policy, was to analyze the social construction of the AIDS vulnerability of truck drivers in the South of Brazil, examining the national HIV/AIDS prevention policies. The discourse of three social actors were analyzed using the Medical Anthropology framework: (i) the national gonvernmental AIDS agency, (ii) the Non Governmental Organizations supported by the National AIDS Program to execute prevention projects targeting truck drivers, and (iii) the truck drivers themselves, passing through Rio Grande do Sul state. Three important themes traverse this study: (i) globalization (and the global/local relations), (ii) the identity of a social group or a community, and (iii) the construction of a sexual culture. To understand the social construction of the truck drivers’ vulnerability, I followed the route that this idea went through different institutions and levels. Beginning at international intergovernmental agencies such as the World Health Organization, the United Nations AIDS Program (UNAIDS) and the World Bank, the course followed through the analysis of scientific research on the theme, and finally the national AIDS agency’s discourse. The route finally came to how NGOs seize and use the idea that truck drivers are a vulnerable group, ending with how the truckers themselves perceive their vulnerability to HIV, AIDS and sexually transmitted infections. The study was limited in scope by the action of NGOs who had developed publicly funded projects targeting truck drivers. Methodologically, the study collected and analyzed data of different origins, types and qualities. Official documents, grey literature, scientific papers on truckers and HIV/AIDS, as well as NGO project proposals were studied. Data collection also involved an ethnography and a survey (N=854) of truck drivers. Both qualitative and quantitative studies of truckers were developed in Rio Grande do Sul, southernmost state of Brazil, in the cities of Porto Alegre, Gravataí, Canoas, Rio Grande and Chuí. Truckers are immersed in a social network, both in the truck stops (fuel stations and customs) and in their places of origin (where family relations prevail). The social universe of the truckstops is not a simply a transitory place: there are rules of conduct, leaderships, social spaces which are symbolic and geographically marked, and a number of persons who maintain diverse relations amongst themselves for a long time. Truck drivers did mention inconsistent use of condoms, specially with regular or fixed partners, that certainly increases their vulnerability to HIV and sexually transmitted infections. However, inconsistent condom use, and the availability of commercial sex workers, is not exclusive to truckers or truck stops. Emphasis is given to the programmatic or institutional vulnerability of truck drivers. AIDS HIV Medical Anthropology Cultural Anthropology Truck drivers Public policy Health vulnerability H1 RA0421 GN
283	Increasing Haul Truck Safety through the use of Virtual Pre-Shift Inspection Training Schaum, Adam Michael 22 June 2007 (has links) On average, there are approximately ten fatal haul truck accidents per year in the United States. The most common causes for haul truck accidents include mechanical problems, inadequate training, and insufficient road/berm maintenance. Due to the frequency and magnitude of haul truck accidents, new training methods are being investigated. With the widespread availability of inexpensive and powerful computers and newer information technology, the ability to incorporate computer based training for miners is becoming more of a possibility. Computer based training is as effective in knowledge acquisition as traditional lecture, and computer based training can also lead to a significant increase in the retention of material. Studies have also shown that more engaging training methods lead to much more effective knowledge acquisition. A computer-based virtual environment training system was developed to supplement current new miner training and address the common causes of fatal accidents. The new training system is a virtual pre-shift inspection of a haul truck, and will train the beginner haul truck operator to identify parts which look defective compared to how the parts look normally. The training will increase the operator's ability to recognize problematic parts and correctly identify the corrective action needed. Increasing the quality of training by providing a very engaging simulated hands-on environment will lead to safer behaviors by the trainees, and ultimately fewer accidents and fatalities. / Master of Science X3D Virtual Reality Virtual Environments Safety Haul Truck Pre-Shift Inspection
284	Black Food Trucks Matter: A Qualitative Study Examining The (Mis)Representation, Underestimation, and Contribution of Black Entrepreneurs In The Food Truck Industry Ariel D Smith (14223191) 11 August 2023 (has links) <p>Food trucks have become increasingly popular over the last decade following the Great Recession of 2008. Scholars have begun to study the food truck phenomenon, its future projected trajectory, and even positioning it within social justice discourse along cultural lines; however, scholarship has yet to address the participation of Black entrepreneurs in the food truck industry.</p> <p><br></p> <p>The objective of this dissertation is to expand the perception of Black food entrepreneurs within the food truck industry by interrogating how Black food truck owners are misrepresented, under analyzed, and underestimated. Using a series of interdisciplinary qualitative methods including introspective analysis, thematic coding analysis, and case studies, I approach this objective by addressing three questions. First, I analyze movies and television to understand where Black-owned food trucks are represented in popular culture and how they are depicted. In doing so, we come to understand that Black business representation, specifically Black food truck representation consistently falls victim to negative stereotypes. These stereotypes can influence the extent to which Black food truck owners are taken seriously and seen as legitimate business leaders in their community. Second, I interview 16 Black food truck entrepreneurs to understand why the mobile food industry appealed to them and how it has become a platform for them to explore other opportunities. Finally, I review eight cities that have launched Black food truck festivals and parks within the last 6 years to gain an understanding of the collective power wielded by Black food truck owners and its impact Black communities. Moreover, this dissertation challenges the myth that collectivism does not exist among Black entrepreneurs and the Black community broadly.</p> Business systems in context Food and hospitality services Business and labour history Entrepreneurship Cinema studies Screen media Digital heritage Heritage and cultural conservation Heritage collections and interpretations Social and cultural anthropology Urban community development Sociology of inequalities Urban sociology and community studies Media studies Consumption and everyday life Cultural and creative industries Cultural studies of nation and region Culture, representation and identity Screen and media culture Food Truck food trucks Black owned Black owned food truck mobile food street food street food vending street food entrepreneurship Black food Black food truck studies food truck studies African American Studies African American foodways Black foodways Black food entrepreneurship Black movies Black television The Food Truck Scholar The Food Truck Scholar Podcast Black business Black businesses Barbershop 3 The Last OG The Chi Think Like a Man food truck festivals food truck park foodtruck Roi Choi The Great Food Truck Race Chef Chef movie Black representation Black men Black women Black men representation Black women representation critical race theory case study introspective analysis Black entrepreneurs African American entrepreneurs food truck industry mobile food vending Black food truck owner Black food truck entrepreneur food truck owner food truck operator food trucker Black food trucker African American food truck owner African American food trucker food truck podcast food truck show storytelling African American storytelling Black studies africana studies entrepreneurial storytelling food studies Black food studies African American food studies enterprise food truck enterprise Black food trucks matter Black businesses matter Buy Black Black dollars Black economics Black dollar soul food southern studies Black diaspora \
285	The concurrent validity of learning potential and psychomotor ability measures for the selection of haul truck operators in an open-pit mine Pelser, Marikie Karen 11 1900 (has links) The purpose of the present study was to determine the concurrent validity of learning potential and psychomotor ability measures for the prediction of haul truck operator (N=128) performance in an open-pit mine. Specific aims were to determine the nature of the relationship between learning potential and psychomotor ability; whether there are higher order cognitive or psychomotor factors present in the combined use of the TRAM 1 and Vienna Test System measures; and the relative contribution of learning potential and psychomotor ability in the prediction of haul truck operator performance. The validity of learning potential and psychomotor ability measures was partially supported. A positive correlation between general (cognitive) ability (g) and psychomotor ability was reported. Factor analysis provided relatively consistent evidence for a general (cognitive) ability factor (g) underlying performance on all measures. The relative contribution of learning potential and psychomotor ability in the prediction of performance could not be established. / Industrial and Organisational Psychology / M. Com. (Industrial and Organisational Psychology) Haul truck operators Open-pit mines selection measures Concurrent Validity Learning Potential Psychomotor Ability 150.287024622 Learning ability--Testing Psychological tests Psychometrics Motor ability--Testing Miners--Psychological tests Truck driving--Testing Vienna Test System
286	Interface Development for Semi-Autonomous Trucks : Visual and Auditory Feedback Eriksson, Frida, Andersson, Märta January 2015 (has links) Vehicles are becoming increasingly autonomous, as automotive industries are investing in innovative technology. Therefore the technology becomes more available and affordable, making it possible for Toyota Material Handling Europe (TMHE) to introduce automated features in their trucks. Vehicles that have a forward collision warning system, and thus are partly autonomous, are involved in less accidents than those without. In manufacturing industries there is currently a problem with truck collisions and an automated solution might be a suitable way to prevent these. When implementing an automation device, human machine interaction and user-friendliness are aspects to keep in mind during the development. The thesis concerns how autonomous features can assist the truck driver, and how to provide the driver with intuitive feedback. The purpose was to ensure the drivers’ and surrounding personnel’s safety as well as increase the productivity. Research was performed regarding in what situation an assisting device is needed and how to communicate information in an intuitive manner to help the driver in this situation. A conceptual interface was developed that allows communication between the driver and a future all-knowing system, that tracks all objects and personnel in a warehouse. The drivers have had a central role in the process. The observations were performed in the TMHE warehouse to identify situations. The most perilous and frequent situation was when drivers need to focus both in the fork and drive wheel directions simultaneously. This either puts the surroundings or the driver in danger. A conceptual interface was developed to help the driver in this situation. This resulted in a concept implementable in both current and future trucks, to harmonise the solution and ensure a safe warehouse environment. A lo-fi prototype was constructed and evaluated iteratively with drivers to ensure the quality and usability of the concept. The resulting feedback solution consists of sounds from speakers mounted in the headrest and a display interface with warning symbols. The sounds are directional to notify the driver if the danger is to the left or right behind his back. If the danger is only semi-close, the driver receives a warning, but if it is very close, the truck is stopped autonomously. The symbols appear on the display simultaneously as the sounds are heard, to provide further feedback. Additionally, an Autonomous Positioning feature has been developed, that consists of symbols and buttons on the display interface, as well as an alert sound from the display to indicate the system’s activation and deactivation. Safety is enhanced since neither personnel nor trucks are in risk of collision when implementing the concept. As the concept helps the driver position the truck effortlessly towards the pallet the productivity is also improved. Interface Interaction HMI Display Development Semi-Autonomous Concept Prototype Forklift Trucks Truck Visual Auditory Feedback Toyota TMHE Design Ergonomics Sound GUI Automation Autonomous Driver User Truckar Truck Gränssnitt Feedback Återkoppling Användare Förare Automation Interaktion Semi-automation Ljud Display Toyota TMHE
287	Volvo Trucks: A Trucker's Pride : Increasing the Quality of Life for American Long-Haul Truckers Vaninetti, Travis January 2012 (has links) Volvo Trucks: A Trucker's Pride The North American trucking industry is in decline. By 2014, the United States is projected to be short 110,000 drivers (Wikipedia). The hardest hit segment is the long-haul sector, due to the difficult lifestyle of the long-haul trucker. Drivers experience long periods of time away from home, mediocre pay, and “miserable” working conditions. In order to revive the struggling industry and refresh the lifeblood of our civilization, the long-haul trucker lifestyle must be made more appealing. This project is a study into how to make the North American Long-Haul trucker lifestyle appealing to future trucker generations through both interior and exterior design. In-depth research found that emotional needs of American long-haul truckers are not being met. Emotional needs are directly linked to the concept of “quality of life”. Therefore, increasing the trucker’s quality of life would help truckers meet their emotional needs and thus help revive the North American trucking industry. Through interviews and questionnaires, pride was determined to be the key emotional need of the American Trucker. These interviews revealed that the best method to appeal to this key emotional need was to rethink the exterior form. It was decided that a design sculpture should be used to illustrate the concept of emotionally appealing transportation. For the interior design, research showed that a trucker’s fundamental human needs were not being met aboard the truck. Expanding the living space on-board and providing truckers access to their basic human needs allow people to truly live life on the road. The Volvo Vision Long-Haul (VLH) helps future truckers take pride in themselves and their lifestyles. Pride comes from the aesthetics of assertive strength and the confident stance of the vehicle. A higher seating position gives drivers a commanding view of the road and the use of noble materials helps drivers feel they live in a quality environment. Onboard, the Volvo VLH maximizes interior space, providing enough room for a trucker to live life on the road. To meet basic human needs, the truck has a shower and toilet onboard, along with a kitchen complete with stove and sink. The lofted bedroom offers feelings of exclusivity and expands upward when the vehicle is parked. This unique expanding space is accessed via a spiral staircase, which stores neatly away when not in use. The Volvo VLH meets the emotional needs of the American long-haul trucker, making the lifestyle appealing to future generations. TJ Vaninetti Vaninetti Travis Vaninetti Volvo Trucks Volvo Emotion and Design Strategic Design Transportation Design Truck Design Car Design Truck Trucking Trucking Industry US Trucking USA Trucking Industry American Trucking
288	The concurrent validity of learning potential and psychomotor ability measures for the selection of haul truck operators in an open-pit mine Pelser, Marikie Karen 11 1900 (has links) The purpose of the present study was to determine the concurrent validity of learning potential and psychomotor ability measures for the prediction of haul truck operator (N=128) performance in an open-pit mine. Specific aims were to determine the nature of the relationship between learning potential and psychomotor ability; whether there are higher order cognitive or psychomotor factors present in the combined use of the TRAM 1 and Vienna Test System measures; and the relative contribution of learning potential and psychomotor ability in the prediction of haul truck operator performance. The validity of learning potential and psychomotor ability measures was partially supported. A positive correlation between general (cognitive) ability (g) and psychomotor ability was reported. Factor analysis provided relatively consistent evidence for a general (cognitive) ability factor (g) underlying performance on all measures. The relative contribution of learning potential and psychomotor ability in the prediction of performance could not be established. / Industrial and Organisational Psychology / M. Com. (Industrial and Organisational Psychology) Haul truck operators Open-pit mines selection measures Concurrent Validity Learning Potential Psychomotor Ability 150.287024622 Learning ability--Testing Psychological tests Psychometrics Motor ability--Testing Miners--Psychological tests Truck driving--Testing Vienna Test System
289	Complex Vehicle Modeling: A Data Driven Approach Schoen, Alexander C. 12 1900 (has links) Indiana University-Purdue University Indianapolis (IUPUI) / This thesis proposes an artificial neural network (NN) model to predict fuel consumption in heavy vehicles. The model uses predictors derived from vehicle speed, mass, and road grade. These variables are readily available from telematics devices that are becoming an integral part of connected vehicles. The model predictors are aggregated over a fixed distance traveled (i.e., window) instead of fixed time interval. It was found that 1km windows is most appropriate for the vocations studied in this thesis. Two vocations were studied, refuse and delivery trucks. The proposed NN model was compared to two traditional models. The first is a parametric model similar to one found in the literature. The second is a linear regression model that uses the same features developed for the NN model. The confidence level of the models using these three methods were calculated in order to evaluate the models variances. It was found that the NN models produce lower point-wise error. However, the stability of the models are not as high as regression models. In order to improve the variance of the NN models, an ensemble based on the average of 5-fold models was created. Finally, the confidence level of each model is analyzed in order to understand how much error is expected from each model. The mean training error was used to correct the ensemble predictions for five K-Fold models. The ensemble K-fold model predictions are more reliable than the single NN and has lower confidence interval than both the parametric and regression models. Neural Network Prediction Fuel Consumption Improvement Ensemble Learning Refuse Truck Complex System Modeling Delivery Truck Vehicle Routing SAE J1321 Synthetic Data Generation Aerodynamic Speed Characteristic Acceleration Feature Importance Influence of Weights Machine Learning Point-wise Error Artificial Neural Network
290	Mission-based Design Space Exploration and Traffic-in-the-Loop Simulation for a Range-Extended Plug-in Hybrid Delivery Vehicle Anil, Vijay Sankar January 2020 (has links) No description available. Automotive Engineering Engineering Mechanical Engineering Sustainability Systems Design Transportation Design Space Exploration Hybrid Vehicles Series Hybrid PHEV Range Extended Hybrid Pickup and Delivery Truck SUMO Traffic Simulation ECMS Dynamic Programming Gaussian Process Architecture Selection Logistics Class 6 Truck Energy Management

Search results