578 resultados para Automotive engineering.
Resumo:
This research project explores how interdisciplinary art practices can provide ways for questioning and envisaging alternative modes of coexistence between humans and the non-humans who together, make up the environment. As a practiceled project, it combines a body of creative work (50%) and this exegesis (50%). My interdisciplinary artistic practice appropriates methods and processes from science and engineering and merges them into artistic contexts for critical and poetic ends. By blending pseudo-scientific experimentation with creative strategies like visual fiction, humour, absurd public performance and scripted audience participation, my work engages with a range of debates around ecology. This exegesis details the interplay between critical theory relating to these debates, the work of other creative practitioners and my own evolving artistic practice. Through utilising methods and processes drawn from my prior career in water engineering, I present an interdisciplinary synthesis that seeks to promote improved understandings of the causes and consequences of our ecological actions and inactions.
Resumo:
Road safety barriers are used to redirect traffic at roadside work-zones. When filled with water, these barriers are able to withstand low to moderate impact speeds up to 50kmh-1. Despite this feature, Portable Water-filled barriers (PWFB) face challenges such as large lateral displacements, tearing and breakage during impact; especially at higher speeds. This study explores the use of composite action to enhance the crashworthiness of PWFBs and enable their usage at higher speeds. Initially, energy absorption capability of water in PWFB is investigated. Then, composite action of the PWFB with the introduction of steel frame is considered to evaluate its enhanced impact performance. Findings of the study show that the initial height of the impact must be lower than the free surface level of water in a PWFB in order for the water to provide significant crash energy absorption. In general, an impact of a road barrier with 80% filled is a good estimation. Furthermore, the addition of a composite structure greatly reduces the probability of tearing by decreasing the strain and impact energy transferred to the shell container. This allows the water to remain longer in the barrier to absorb energy via inertial displacements and sloshing response. Information from this research will aid in the design of new generation roadside safety structures aimed to increase safety in modern roadways.
Resumo:
This research study examines qualitatively and quantitatively the influence of introducing an activity in the traditional engineering classroom. It studies instances of active learning and its relationship with the student learning outcomes. The primary purpose of this study was to compare the learning outcomes of students who were involved in an active TLA with those students who were not, instead they learned under traditional teaching and studying approaches. I present the argument that the introduction of a TLA in class stimulates student engagement bringing enormous benefits to student learning. The outcomes of this study were measured using qualitative and quantitative data to evaluate the levels of student engagement, achievement and satisfaction in the terms of Intended Learning Outcomes (ILOs). Results indicate that students held positive attitude towards the activities in class and also, that a positive link between TLA, learning approach and learning outcome exist. It also provides insights about the potential benefits of active learning when compared with traditional, passive and teacher-centred methods of teaching & learning.
Resumo:
Magnesium and its alloys have shown a great potential in effective hydrogen storage due to their advantages of high volumetric/gravimetric hydrogen storage capacity and low cost. However, the use of these materials in fuel cells for automotive applications at the present time is limited by high hydrogenation temperature and sluggish sorption kinetics. This paper presents the recent results of design and development of magnesium-based nanocomposites demonstrating the catalytic effects of carbon nanotubes and transition metals on hydrogen adsorption in these materials. The results are promising for the application of magnesium materials for hydrogen storage, with significantly reduced absorption temperatures and enhanced ab/desorption kinetics. High level Density Functional Theory calculations support the analysis of the hydrogenation mechanisms by revealing the detailed atomic and molecular interactions that underpin the catalytic roles of incorporated carbon and titanium, providing clear guidance for further design and development of such materials with better hydrogen storage properties.
Resumo:
In this study, a hierarchical nano/microfibrous chitosan/collagen scaffold that approximates structural and functional attributes of native extracellular matrix (ECM), has been developed for applicability in skin tissue engineering. Scaffolds were produced by electrospinning of chitosan followed by imbibing of collagen solution, freeze-drying and subsequent cross-linking of two polymers. Scanning electron microscopy showed formation of layered scaffolds with nano/microfibrous architechture. Physico-chemical properties of scaffolds including tensile strength, swelling behavior and biodegradability were found satisfactory for intended application. 3T3 fibroblasts and HaCaT keratinocytes showed good in vitro cellular response on scaffolds thereby indicating the matrices′ cytocompatible nature. Scaffolds tested in an ex vivo human skin equivalent (HSE) wound model, as a preliminary alternative to animal testing, showed keratinocyte migration and wound re-epithelization — a pre-requisite for healing and regeneration. Taken together, the herein proposed chitosan/collagen scaffold, shows good potential for skin tissue engineering.
Resumo:
Targeting females at high school or earlier may be a key towards engaging them in science, technology, engineering and mathematics (STEM) education. This ethnographic study, part of a three-year longitudinal research project, investigated Year 8 female students’ learning about engineering concepts associated with designing, constructing, testing, and evaluating a catapult. There was a series of lead-up lessons and four lessons for the catapult challenge (total of 18 x 45-minute lessons) over a nine-week period. Data from two girls within a focus group showed that they needed to: (1) receive clarification on engineering terms to facilitate more fluent discourse, (2) question and debate conceptual understandings without peers being judgemental, and (3) have multiple opportunities for engaging with materials towards designing, constructing and explaining key concepts learnt. There are implications for teachers facilitating STEM education, such as: clarifying STEM terms, articulating how students can interact in non-judgmental ways, and providing multiple opportunities for interacting within engineering education.
Resumo:
Increases in functionality, power and intelligence of modern engineered systems led to complex systems with a large number of interconnected dynamic subsystems. In such machines, faults in one subsystem can cascade and affect the behavior of numerous other subsystems. This complicates the traditional fault monitoring procedures because of the need to train models of the faults that the monitoring system needs to detect and recognize. Unavoidable design defects, quality variations and different usage patterns make it infeasible to foresee all possible faults, resulting in limited diagnostic coverage that can only deal with previously anticipated and modeled failures. This leads to missed detections and costly blind swapping of acceptable components because of one’s inability to accurately isolate the source of previously unseen anomalies. To circumvent these difficulties, a new paradigm for diagnostic systems is proposed and discussed in this paper. Its feasibility is demonstrated through application examples in automotive engine diagnostics.
Resumo:
Faculty and reference librarians at the Queensland University of Technology have collaborated in an attempt to improve the quality of literature reviews in civil engineering final -year research projects. This article describes the instructional program devised and the level of faculty support for the librarians' contribution, and presents survey results revealing how students could most benefit from BI and how the classroom collaboration affected student project work. The authors offer some observations about the possible impact of 81 in general, and on engineers in particular, which may provide a focus for future research.
Resumo:
Vehicular accidents are one of the deadliest safety hazards and accordingly an immense concern of individuals and governments. Although, a wide range of active autonomous safety systems, such as advanced driving assistance and lane keeping support, are introduced to facilitate safer driving experience, these stand-alone systems have limited capabilities in providing safety. Therefore, cooperative vehicular systems were proposed to fulfill more safety requirements. Most cooperative vehicle-to-vehicle safety applications require relative positioning accuracy of decimeter level with an update rate of at least 10 Hz. These requirements cannot be met via direct navigation or differential positioning techniques. This paper studies a cooperative vehicle platform that aims to facilitate real-time relative positioning (RRP) among adjacent vehicles. The developed system is capable of exchanging both GPS position solutions and raw observations using RTCM-104 format over vehicular dedicated short range communication (DSRC) links. Real-time kinematic (RTK) positioning technique is integrated into the system to enable RRP to be served as an embedded real-time warning system. The 5.9 GHz DSRC technology is adopted as the communication channel among road-side units (RSUs) and on-board units (OBUs) to distribute GPS corrections data received from a nearby reference station via the Internet using cellular technologies, by means of RSUs, as well as to exchange the vehicular real-time GPS raw observation data. Ultimately, each receiving vehicle calculates relative positions of its neighbors to attain a RRP map. A series of real-world data collection experiments was conducted to explore the synergies of both DSRC and positioning systems. The results demonstrate a significant enhancement in precision and availability of relative positioning at mobile vehicles.
Resumo:
In this paper, problems are described which are related to the ergonomic assessment of vehicle package design in vehicle systems engineering. The traditional approach, using questionnaire techniques for a subjective assessment of comfort related to package design, is compared to a biomechanical approach. An example is given for ingress design. The biomechanical approach is based upon objective postural data. The experimental setup for the study is described and methods used for the biomechanical analysis are explained. Because the biomechanic assessment requires not only a complex experimental setup but also time consuming data processing, a systematic reduction and preparation of biomechanic data for classification with an Artificial Neural Network significantly improves the economy of the biomechanical method.
Resumo:
The performance of visual speech recognition (VSR) systems are significantly influenced by the accuracy of the visual front-end. The current state-of-the-art VSR systems use off-the-shelf face detectors such as Viola- Jones (VJ) which has limited reliability for changes in illumination and head poses. For a VSR system to perform well under these conditions, an accurate visual front end is required. This is an important problem to be solved in many practical implementations of audio visual speech recognition systems, for example in automotive environments for an efficient human-vehicle computer interface. In this paper, we re-examine the current state-of-the-art VSR by comparing off-the-shelf face detectors with the recently developed Fourier Lucas-Kanade (FLK) image alignment technique. A variety of image alignment and visual speech recognition experiments are performed on a clean dataset as well as with a challenging automotive audio-visual speech dataset. Our results indicate that the FLK image alignment technique can significantly outperform off-the shelf face detectors, but requires frequent fine-tuning.
Resumo:
Policy makers increasingly recognise that an educated workforce with a high proportion of Science, Technology, Engineering and Mathematics (STEM) graduates is a pre-requisite to a knowledge-based, innovative economy. Over the past ten years, the proportion of first university degrees awarded in Australia in STEM fields is below the global average and continues to decrease from 22.2% in 2002 to 18.8% in 2010 [1]. These trends are mirrored by declines between 20% and 30% in the proportions of high school students enrolled in science or maths. These trends are not unique to Australia but their impact is of concern throughout the policy-making community. To redress these demographic trends, QUT embarked upon a long-term investment strategy to integrate education and research into the physical and virtual infrastructure of the campus, recognising that expectations of students change as rapidly as technology and learning practices change. To implement this strategy, physical infrastructure refurbishment/re-building is accompanied by upgraded technologies not only for learning but also for research. QUT’s vision for its city-based campuses is to create vibrant and attractive places to learn and research and to link strongly to the wider surrounding community. Over a five year period, physical infrastructure at the Gardens Point campus was substantially reconfigured in two key stages: (a) a >$50m refurbishment of heritage-listed buildings to encompass public, retail and social spaces, learning and teaching “test beds” and research laboratories and (b) destruction of five buildings to be replaced by a $230m, >40,000m2 Science and Engineering Centre designed to accommodate retail, recreation, services, education and research in an integrated, coordinated precinct. This landmark project is characterised by (i) self-evident, collaborative spaces for learning, research and social engagement, (ii) sustainable building practices and sustainable ongoing operation and; (iii) dynamic and mobile re-configuration of spaces or staffing to meet demand. Innovative spaces allow for transformative, cohort-driven learning and the collaborative use of space to prosecute joint class projects. Research laboratories are aggregated, centralised and “on display” to the public, students and staff. A major visualisation space – the largest multi-touch, multi-user facility constructed to date – is a centrepiece feature that focuses on demonstrating scientific and engineering principles or science oriented scenes at large scale (e.g. the Great Barrier Reef). Content on this visualisation facility is integrated with the regional school curricula and supports an in-house schools program for student and teacher engagement. Researchers are accommodated in a combined open-plan and office floor-space (80% open plan) to encourage interdisciplinary engagement and cross-fertilisation of skills, ideas and projects. This combination of spaces re-invigorates the on-campus experience, extends educational engagement across all ages and rapidly enhances research collaboration.
Resumo:
Critical-sized osteochondral defects are clinically challenging, with limited treatment options available. By engineering osteochondral grafts using a patient's own cells and osteochondral scaffolds designed to facilitate cartilage and bone regeneration, osteochondral defects may be treated with less complications and better long-term clinical outcomes. Scaffolds can influence the development and structure of the engineered tissue, and there is an increased awareness that osteochondral tissue engineering concepts need to take the in vivo complexities into account in order to increase the likelihood of successful osteochondral tissue repair. The developing trend in osteochondral tissue engineering is the utilization of multiphasic scaffolds to recapitulate the multiphasic nature of the native tissue. Cartilage and bone have different structural, mechanical, and biochemical microenvironments. By designing osteochondral scaffolds with tissue-specific architecture, it may be possible to enhance osteochondral repair within shorter timeframe. While there are promising in vivo outcomes using multiphasic approaches, functional regeneration of osteochondral constructs still remains a challenge. In this review, we provide an overview of in vivo osteochondral repair studies that have taken place in the past three years, and define areas which needs improvement in future studies
Resumo:
This article presents a method for making highly porous biodegradable scaffold that may ultimately be used for tissue engineering. Poly(L-lactic-co-1-caprolactone) acid (70:30) (PLCL) scaffold was produced using the solvent casting/leaching out method, which entails dissolving the polymer and adding a porogen that is then leached out by immersing the scaffold in distillated water. Tensile tests were performed for three types of scaffolds, namely pre-wetted, dried, and UV-irradiated scaffolds and their mechanical properties were measured. The prewetted PLCL scaffold possessed a modulus of elasticity 0.92+0.09 MPa, a tensile strength of 0.12+0.03 MPa and an ultimate strain of 23+5.3%. No significant differences in the modulus elasticity, tensile strength, nor ultimate strain were found between the pre-wetted, dried, and UV irradiated scaffolds. The PLCL scaffold was seeded by human fibroblasts in order to evaluate its biocompatibility by Alamar bluew assays. After 10 days of culture, the scaffolds showed good biocompatibility and allowed cell proliferation. However, the fibroblasts stayed essentially at the surface. This study shows the possibility to use the PLCL scaffold in dynamic mechanical conditions for tissue engineering