963 resultados para materials management


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Tertiary institutions now face serious challenges. Modern industry requires engineering graduates with strong knowledge of modern technologies, highly practical focus, management skills, ability to work individually and in a team, understanding of environmental issues and many other skills and graduate attributes. Institutions in the tertiary sector change courses and modify curriculum to reflect challenges of the modern industry and make engineering graduates better prepared for the “real world”. Queensland University of Technology in the recent years introduced an innovative structure of engineering courses with a common core for Bachelor of Engineering Mechanical, Infomechatronics and Medical, where manufacturing is taught in conjunction with engineering design and engineering materials. In this paper we discuss the innovative curriculum structure, teaching and learning approaches of coherent delivery of manufacturing in conjunction with engineering design and

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In response to the call for sustainability education in construction courses, higher education institutions have started to incorporate sustainability components into their construction courses to some extent. This research aims to investigate sustainability embedded in construction management (CM) courses using the Queensland University of Technology as a case study. A content analysis of its CM course structure, unit aims, learning objectives and lecture materials is conducted to examine the sustainability elements incorporated into the CM curriculum. The results show that the course incorporates sustainability components into the existing course structure mainly through horizontal integration, embedding sustainability into general units rather than as an add-on subject. Additionally, the sustainability topics embedded in the course cover a comparatively broad and balanced range of sustainability categories, i.e. background knowledge, policies and regulations, environmental issues, social issues and economic issues as well as technology and innovation, although social sustainability aspects need to be further strengthened. This research addresses the need for urgency in the development of an effective sustainability education framework for construction courses. It is expected that the findings from this study will facilitate the improvement of sustainability education in construction courses generally.

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This study estimates the environmental efficiency of international listed firms in 10 worldwide sectors from 2007 to 2013 by applying an order-m method, a non-parametric approach based on free disposal hull with subsampling bootstrapping. Using a conventional output of gross profit and two conventional inputs of labor and capital, this study examines the order-m environmental efficiency accounting for the presence of each of 10 undesirable inputs/outputs and measures the shadow prices of each undesirable input and output. The results show that there is greater potential for the reduction of undesirable inputs rather than bad outputs. On average, total energy, electricity, or water usage has the potential to be reduced by 50%. The median shadow prices of undesirable inputs, however, are much higher than the surveyed representative market prices. Approximately 10% of the firms in the sample appear to be potential sellers or production reducers in terms of undesirable inputs/outputs, which implies that the price of each item at the current level has little impact on most of the firms. Moreover, this study shows that the environmental, social, and governance activities of a firm do not considerably affect environmental efficiency.

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Introduction: Injuries in the lower extremity are considered to have multifactorial causes, whilst people with heel pain represent the most frequent cause of visits to health professionals. Managing these patients can be very difficult. The purpose of this research is to identify key variables which can influence foot health in patients with heel pain. Materials and method: A cross-sectional observational study was carried out with a sample of sixty-two participants recruited from the Educational Welfare Unit of the University of Malaga. The therapists, blinded for the study, fill in the data with anthropometric information and the FPI, while participants fill in the foot health status questionnaire, FHSQ. The most significant results reveal that there is a moderate relation between the clinical variables and the FHSQ commands. The most significant contribution is the BMI in the foot health status questionnaire. Conclusion: The variables which can help manage clinical subjects with heel pain are age, BMI, footwear and FPI (left foot).

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The heat pipe is an innovative engineering structure characterized by its capacity to transfer large quantities of heat through relatively small cross-sectional areas with very small temperature differences; it also possesses high thermal conductance and low thermal impedance. In recent times, heat pipes in various forms and designs have found a wide variety of applications. This paper briefly presents the basic concepts of heat pipes, recent innovations in design and their applications.

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In 2002, AFL Queensland and the Brisbane Lions Football Club approached the Department of Primary Industries and Fisheries (Queensland) for advice on improving their Premier League sports fields. They were concerned about player safety and dissatisfaction with playing surfaces, particularly uneven turf cover and variable under-foot conditions. They wanted to get the best from new investments in ground maintenance equipment and irrigation infrastructure. Their sports fields were representative of community-standard, multi-use venues throughout Australia; generally ‘natural’ soil fields, with low maintenance budgets, managed by volunteers. Improvements such as reconstruction, drainage, or regular re-turfing are generally not affordable. Our project aimed to: (a) Review current world practice and performance benchmarks; (b) Demonstrate best-practice management for community-standard fields; (c) Adapt relevant methods for surface performance testing; (d) Assess current soils, and investigate useful amendments; (e) Improve irrigation system performance; and (e) Build industry capacity and encourage patterns for ongoing learning. Most global sports field research focuses on elite, sand-based fields. We adjusted elite standards for surface performance (hardness, traction, soil moisture, evenness, sward cover/height) and maintenance programs, to suit community-standard fields with lesser input resources. In regularly auditing ground conditions across 12 AFLQ fields in SE QLD, we discovered surface hardness (measured by Clegg Hammer) was the No. 1 factor affecting player safety and surface performance. Other important indices were turf coverage and surface compaction (measured by penetrometer). AFLQ now runs regularly audits affiliated fields, and closes grounds with hardness readings greater than 190 Gmax. Aerating every two months was the primary mechanical practice improving surface condition and reducing hardness levels to < 110 Gmax on the renovated project fields. With irrigation installation, these fields now record surface conditions comparable to elite fields. These improvements encouraged many other sporting organisations to seek advice / assistance from the project team. AFLQ have since substantially invested in an expanded ground improvement program, to cater for this substantially increased demand. In auditing irrigation systems across project fields, we identified low maintenance (with < 65% of sprinklers operating optimally) as a major problem. Retrofitting better nozzles and adjusting sprinklers improved irrigation distribution uniformity to 75-80%. Research showed that reducing irrigation frequency to weekly, and preparedness to withhold irrigation longer after rain, reduced irrigation requirement by 30-50%, compared to industry benchmarks of 5-6 ML/ha/annum. Project team consultation with regulatory authorities enhanced irrigation efficiency under imposed regional water restrictions. Laboratory studies showed incorporated biosolids / composts, or topdressed crumb rubber, improved compaction resistance of soils. Field evaluations confirmed compost incorporation significantly reduced surface hardness of high wear areas in dry conditions, whilst crumb rubber assisted turf persistence into early winter. Neither amendment was a panacea for poor agronomic practices. Under the auspices of the project Trade Mark Sureplay®, we published > 80 articles, and held > 100 extension activities involving > 2,000 participants. Sureplay® has developed a multi-level curator training structure and resource materials, subject to commercial implementation. The partnerships with industry bodies (particularly AFLQ), frequent extension activities, and engagement with government/regulatory sectors have been very successful, and are encouraged for any future work. Specific aspects of sports field management for further research include: (a) Understanding of factors affecting turf wear resistance and recovery, to improve turf persistence under wear; (b) Simple tests for pinpointing areas of fields with high hardness risk; and (c) Evaluation of new irrigation infrastructure, ‘water-saving’ devices, and irrigation protocols, in improving water use and turf cover outcomes.

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Synthetic, natural, or composite, biomaterials occupy a key position in the management of disease and support continuous advancement of health care. Clinical utility of many permanent and biodegradable implants can be significantly improved via surface modification. Here, we discuss a novel polymer material developed from essential oil-based monoterpene alcohol using plasma polymerisation. The developed coatings are cytocompatible and limit adhesion and proliferation of a variety of pathogens. The coating can also be used to control degradation behaviour of resorbable materials, such as magnesium.

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This paper analyses the influence of management on Technical Efficiency Change (TEC) and Technological Progress (TP) in the communication equipment and consumer electronics sub-sectors of Indian hardware electronics industry. Each sub-sector comprises 13 sample firms for two time periods.The primary objective is to determine the relative contribution of TP and TEC to TFP Growth (TFPG) and to establish the influence of firm specific operational management decision variables on these two components. The study finds that both the sub-sectors have strived and achieved steady TP but not TEC in the period of economic liberalisation to cope with the intensifying competition. The management decisions with respect to asset and profit utilization, vertical integration, among others, improved TP and TE in the sub-sectors. However, R&D investments and technology imports proved costly for TFP indicating inadequate efforts and/or poor resource utilisation by the management. Management was found to be complacent in terms of improving or developing their own technology as indicated by their higher dependence on import of raw materials and no influence of R&D on TP.

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Cell voltage for a fully charged-substrate-integrated lead-carbon hybrid ultracapacitor is about 2.3 V. Therefore, for applications requiring higher DC voltage, several of these ultracapacitors need to be connected in series. However, voltage distribution across each series-connected ultracapacitor tends to be uneven due to tolerance in capacitance and parasitic parallel-resistance values. Accordingly, voltage-management circuit is required to protect constituent ultracapacitors from exceeding their rated voltage. In this study, the design and characterization of the substrate-integrated lead-carbon hybrid ultracapacitor with co-located terminals is discussed. Voltage-management circuit for the ultracapacitor is presented, and its effectiveness is validated experimentally.

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Phase-change cooling technique is a suitable method for thermal management of electronic equipment subjected to transient or cyclic heat loads. The thermal performance of a phase-change based heat sink under cyclic heat load depends on several design parameters, namely, applied heat flux, cooling heat transfer coefficient, thermophysical properties of phase-change materials (PCMs), and physical dimensions of phase-change storage system during melting and freezing processes. A one-dimensional conduction heat transfer model is formulated to evaluate the effectiveness of preliminary design of practical PCM-based energy storage units. In this model, the phase-change process of the PCM is divided into melting and solidification subprocesses, for which separate equations are written. The equations are solved sequentially and an explicit closed-form solution is obtained. The efficacy of analytical model is estimated by comparing with a finite-volume-based numerical solution for both transient and cyclic heat loads.

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An efficient buffer layer scheme has been designed to address the issue of curvature management during metalorganic chemical vapour deposition growth of GaN on Si (111) substrate. This is necessary to prevent cracking of the grown layer during post-growth cooling down from growth temperature to room temperature and to achieve an allowable bow (<40 m) in the wafer for carrying out lithographic processes. To meet both these ends simultaneously, the stress evolution in the buffer layers was observed carefully. The reduction in precursor flow during the buffer layer growth provided better control over curvature evolution in the growing buffer layers. This has enabled the growth of a suitable high electron mobility transistor (HEMT) stack on 2'' Si (111) substrate of 300 m thickness with a bow as low as 11.4 m, having a two-dimensional electron gas (2DEG) of mobility, carrier concentration, and sheet resistance values 1510 cm(2)/V-s, 0.96 x 10(13)/cm(2), and 444 /, respectively. Another variation of similar technique resulted in a bow of 23.4 m with 2DEG mobility, carrier concentration, and sheet resistance values 1960 cm(2)/V-s, 0.98 x 10(13)/cm(2), and 325 /, respectively.

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Executive Summary: Tropical marine ecosystems in the Caribbean region are inextricably linked through the movement of pollutants, nutrients, diseases, and other stressors, which threaten to further degrade coral reef communities. The magnitude of change that is occurring within the region is considerable, and solutions will require investigating pros and cons of networks of marine protected areas (MPAs), cooperation of neighboring countries, improved understanding of how external stressors degrade local marine resources, and ameliorating those stressors. Connectivity can be broadly defined as the exchange of materials (e.g., nutrients and pollutants), organisms, and genes and can be divided into: 1) genetic or evolutionary connectivity that concerns the exchange of organisms and genes, 2) demographic connectivity, which is the exchange of individuals among local groups, and 3) oceanographic connectivity, which includes flow of materials and circulation patterns and variability that underpin much of all these exchanges. Presently, we understand little about connectivity at specific locations beyond model outputs, and yet we must manage MPAs with connectivity in mind. A key to successful MPA management is how to most effectively work with scientists to acquire the information managers need. Oceanography connectivity is poorly understood, and even less is known about the shape of the dispersal curve for most species. Dispersal kernels differ for various systems, species, and life histories and are likely highly variable in space and time. Furthermore, the implications of different dispersal kernels on population dynamics and management of species is unknown. However, small dispersal kernels are the norm - not the exception. Linking patterns of dispersal to management options is difficult given the present state of knowledge. The behavioral component of larval dispersal has a major impact on where larvae settle. Individual larval behavior and life history details are required to produce meaningful simulations of population connectivity. Biological inputs are critical determinants of dispersal outcomes beyond what can be gleaned from models of passive dispersal. There is considerable temporal and spatial variation to connectivity patterns. New models are increasingly being developed, but these must be validated to understand upstream-downstream neighborhoods, dispersal corridors, stepping stones, and source/sink dynamics. At present, models are mainly useful for providing generalities and generating hypotheses. Low-technology approaches such as drifter vials and oceanographic drogues are useful, affordable options for understanding local connectivity. The “silver bullet” approach to MPA design may not be possible for several reasons. Genetic connectivity studies reveal divergent population genetic structures despite similar larval life histories. Historical stochasticity in reproduction and/or recruitment likely has important, longlasting consequences on present day genetic structure. (PDF has 200 pages.)

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In addition to providing vital ecological services, coastal areas of North Carolina provide prized areas for habitation, recreation, and commercial fisheries. However, from a management perspective, the coasts of North Carolina are highly variable and complex. In-water constituents such as nutrients, suspended sediments, and chlorophyll a concentration can vary significantly over a broad spectrum of time and space scales. Rapid growth and land-use change continue to exert pressure on coastal lands. Coastal environments are also very vulnerable to short-term (e.g., hurricanes) and long-term (e.g., sea-level rise) natural changes that can result in significant loss of life, economic loss, or changes in coastal ecosystem functioning. Hence, the dynamic nature, effects of human-induced change over time, and vulnerability of coastal areas make it difficult to effectively monitor and manage these important state and national resources using traditional data collection technologies such as discrete monitoring stations and field surveys. In general, these approaches provide only a sparse network of data over limited time and space scales and generally are expensive and labor-intensive. Products derived from spectral images obtained by remote sensing instruments provide a unique vantage point from which to examine the dynamic nature of coastal environments. A primary advantage of remote sensing is that the altitude of observation provides a large-scale synoptic view relative to traditional field measurements. Equally important, the use of remote sensing for a broad range of research and environmental applications is now common due to major advances in data availability, data transfer, and computer technologies. To facilitate the widespread use of remote sensing products in North Carolina, the UNC Coastal Studies Institute (UNC-CSI) is developing the capability to acquire, process, and analyze remotely sensed data from several remote sensing instruments. In particular, UNC-CSI is developing regional remote sensing algorithms to examine the mobilization, transport, transformation, and fate of materials between coupled terrestrial and coastal ocean systems. To illustrate this work, we present the basic principles of remote sensing of coastal waters in the context of deriving information that supports efficient and effective management of coastal resources. (PDF contains 4 pages)