953 resultados para Process resources
Resumo:
Optimisation of Organic Rankine Cycle (ORCs) for binary-cycle geothermal applications could play a major role in determining the competitiveness of low to moderate temperature geothermal resources. Part of this optimisation process is matching cycles to a given resource such that power output can be maximised. Two major and largely interrelated components of the cycle are the working fluid and the turbine. Both components need careful consideration: the selection of working fluid and appropriate operating conditions as well as optimisation of the turbine design for those conditions will determine the amount of power that can be extracted from a resource. In this paper, we present the rationale for the use of radial-inflow turbines for ORC applications and the preliminary design of several radial-inflow machines based on a number of promising ORC systems that use five different working fluids: R134a, R143a, R236fa, R245fa and n-Pentane. Preliminary meanline analysis lead to the generation of turbine designs for the various cycles with similar efficiencies (77%) but large differences in dimensions (139–289 mm rotor diameter). The highest performing cycle, based on R134a, was found to produce 33% more net power from a 150 °C resource flowing at 10 kg/s than the lowest performing cycle, based on n-Pentane.
Resumo:
Optimisation of Organic Rankine Cycles (ORCs) for binary-cycle geothermal applications could play a major role in the competitiveness of low to moderate temperature geothermal resources. Part of this optimisation process is matching cycles to a given resource such that power output can be maximised. Two major and largely interrelated components of the cycle are the working fluid and the turbine. Both components need careful consideration. Due to the temperature differences in geothermal resources a one-size-fits-all approach to surface power infrastructure is not appropriate. Furthermore, the traditional use of steam as a working fluid does not seem practical due to the low temperatures of many resources. A variety of organic fluids with low boiling points may be utilised as ORC working fluids in binary power cycle loops. Due to differences in thermodynamic properties, certain fluids are able to extract more heat from a given resource than others over certain temperature and pressure ranges. This enables the tailoring of power cycle infrastructure to best match the geothermal resource through careful selection of the working fluid and turbine design optimisation to yield the optimum overall cycle performance. This paper presents the rationale for the use of radial-inflow turbines for ORC applications and the preliminary design of several radial-inflow turbines based on a selection of promising ORC cycles using five different high-density working fluids: R134a, R143a, R236fa, R245fa and n-Pentane at sub- or trans-critical conditions. Numerous studies published compare a variety of working fluids for various ORC configurations. However, there is little information specifically pertaining to the design and implementation of ORCs using realistic radial turbine designs in terms of pressure ratios, inlet pressure, rotor size and rotational speed. Preliminary 1D analysis leads to the generation of turbine designs for the various cycles with similar efficiencies (77%) but large differences in dimensions (139289 mm rotor diameter). The highest performing cycle (R134a) was found to produce 33% more net power from a 150°C resource flowing at 10 kg/s than the lowest performing cycle (n-Pentane).
Resumo:
As features of the landscape, waterfalls have been studied extensively by geographers, but the names given to these landforms have received relatively little scholarly attention. This paper examines the naming of waterfalls and addresses the question of classifying these hydronyms. The subject is considered in a global historical context, focusing on place names in the anglophone world. Until the 18th and 19th centuries, relatively few waterfalls were named.With the beginning of the Industrial Revolution, water power rose in economic importance, and at the same time, there was a growing scientific and aesthetic engagement with the landscape. These developments are suggested as reasons for the increased interest in waterfalls which were then being recorded in topographical literature and on maps, individual names being given to increasing numbers of falls. European exploration added to the knowledge of the world’s waterfalls, many of which were given names by their ‘discoverers’. This naming process accelerated with the growth of domestic and overseas tourism which exploited scenic resources such as waterfalls. Until now, research on the names of waterfalls has been fragmentary, and the classification of these hydronyms has been neglected. This paper demonstrates that waterfall names can be classified in accordance with a recognised toponymic typology. Using examples drawn from waterfall guidebooks, databases, maps, and other sources, the following discussion supports George Stewart’s claim that his toponymic classification is valid for place names of all kinds.
Resumo:
Mobile telecommunications have become a key lifestyle and technological trend of the twenty first century. In the context of increased urbanism and pressure on cites for citizen engagement for the purpose of creating good public places the potential of these technologies raises critical questions for planning professionals. Even though technology has become integral to all functions within our urban environment, little is known about perceptions and relationship between urban planners and the ubiquitous, ever-present digital layer of urban data and information. This paper explores this issue, via three focus groups and an additional follow-up interview with planners from local and state government, education and private sector. This paper explores the issues of integrating information and communication technologies into planning practice and the affordances that these technologies offer for community consultation and placemaking.
Resumo:
Optimal Asset Maintenance decisions are imperative for efficient asset management. Decision Support Systems are often used to help asset managers make maintenance decisions, but high quality decision support must be based on sound decision-making principles. For long-lived assets, a successful Asset Maintenance decision-making process must effectively handle multiple time scales. For example, high-level strategic plans are normally made for periods of years, while daily operational decisions may need to be made within a space of mere minutes. When making strategic decisions, one usually has the luxury of time to explore alternatives, whereas routine operational decisions must often be made with no time for contemplation. In this paper, we present an innovative, flexible decision-making process model which distinguishes meta-level decision making, i.e., deciding how to make decisions, from the information gathering and analysis steps required to make the decisions themselves. The new model can accommodate various decision types. Three industrial case studies are given to demonstrate its applicability.
Resumo:
As business process management technology matures, organisations acquire more and more business process models. The management of the resulting collections of process models poses real challenges. One of these challenges concerns model retrieval where support should be provided for the formulation and efficient execution of business process model queries. As queries based on only structural information cannot deal with all querying requirements in practice, there should be support for queries that require knowledge of process model semantics. In this paper we formally define a process model query language that is based on semantic relationships between tasks in process models and is independent of any particular process modelling notation.
Resumo:
A recent Australian literature digitisation project uncovered some surprising discoveries in the children’s books that it digitised. The Children’s Literature Digital Resources (CLDR) Project digitised children’s books that were first published between 1851 to 1945 and made them available online through AustLit: The Australian Literature Resource. The digitisation process also preserved, within the pages of those books, a range of bookplates, book labels, inscriptions, and loose ephemera. This material allows us to trace the provenance of some of the digitised works, some of which came from the personal libraries of now-famous authors, and others from less celebrated sources. These extra-textual traces can contribute to cultural memory of the past by providing evidence of how books were collected and exchanged, and what kinds of books were presented as prizes in schools and Sunday schools. They also provide insight into Australian literary and artistic networks, particularly of the first few decades of the 20th century. This article describes the kinds of material uncovered in the digitisation process and suggests that the material provides insights into literary and cultural histories that might otherwise be forgotten. It also argues that the indexing of this material is vital if it is not to be lost to future researchers.
Resumo:
The process of researching children’s literature from the past is a growing challenge as resources age and are increasingly treated as rare items, stored away within libraries and other research centres. In Australia, researchers and librarians have collaborated with the bibliographic database AustLit: The Australian Literature Resource to produce the Australian Children’s Literature Digital Resources Project (CLDR). This Project aims to address the growing demand for online access to rare children’s literature resources, and demonstrates the research potential of early Australian children’s literature by supplementing the collection with relevant critical articles. The CLDR project is designed with a specific focus and provides access to full text Australian children’s literature from European settlement to 1945. The collection demonstrates a need and desire to preserve literature treasures to prevent losing such collections in a digital age. The collection covers many themes relevant to the conference including, trauma, survival, memory, survival, hauntings, and histories. The resource provides new and exciting ways with which to research children’s literature from the past and offers a fascinating repository to scholars and professionals of ranging disciplines who are in interested in Australian children’s literature.
Resumo:
Asset management (AM) processes play an important role in assisting enterprises to manage their assets more efficiently. To visualise and improve AM processes, the processes need to be modelled using certain process modelling methodologies. Understanding the requirements for AM process modelling is essential for selecting or developing effective AM process modelling methodologies. However, little research has been done on analysing the requirements. This paper attempts to fill this gap by investigating the features of AM processes. It is concluded that AM process modelling requires intuitive representation of its processes, ‘fast’ implementation of the process modelling, effective evaluation of the processes and sound system integration.
Resumo:
The use of material artefacts within the design process is a long-standing and continuing characteristic of interaction design. Established methods, such as prototyping, which have been widely adopted by educators and practitioners, are seeing renewed research interest and being reconsidered in light of the evolving needs of the field. Alongside this, the past decade has seen the introduction and adoption of a diverse range of novel design methods into interaction design, such as cultural probes, technology probes, context mapping, and provotypes.
Resumo:
There have been many improvements in Australian engineering education since the 1990s. However, given the recent drive for assuring the achievement of identified academic standards, more progress needs to be made, particularly in the area of evidence-based assessment. This paper reports on initiatives gathered from the literature and engineering academics in the USA, through an Australian National Teaching Fellowship program. The program aims to establish a process to help academics in designing and implementing evidence-based assessments that meet the needs of not only students and the staff that teach them, but also industry as well as accreditation bodies. The paper also examines the kinds and levels of support necessary for engineering academics, especially early career ones, to help meet the expectations of the current drive for assured quality and standards of both research and teaching. Academics are experiencing competing demands on their time and energy with very high expectations in research performance and increased teaching responsibilities, although many are researchers who have not had much pedagogic training. Based on the literature and investigation of relevant initiatives in the USA, we conducted interviews with several identified experts and change agents who have wrought effective academic cultural change within their institutions and beyond. These reveal that assuring the standards and quality of student learning outcomes through evidence-based assessments cannot be appropriately addressed without also addressing the issue of pedagogic training for academic staff. To be sustainable, such training needs to be complemented by a culture of on-going mentoring support from senior academics, formalised through the university administration, so that mentors are afforded resources, time, and appropriate recognition.
Resumo:
Empirical research in business process management(BPM) is coming of age. In 2009, when the inaugural ER-BPM workshop was held, the field of BPM research was characterized by a strong emphasis on solution development, but also by an increasing demand for insights or evaluations of BPM technology based on dedicated empirical research strategies. The ER-BPM workshop series was created to provide an international forum for researchers to discuss and present such research.
Resumo:
Environmental issues continue to capture international headlines and remain the subject of intense intellectual, political and public debate. As a result, environmental law is widely recognised as the fastest growing area of international jurisprudence. This, combined with the rapid expansion of environmental agreements and policies, has created a burgeoning landscape of administrative, regulatory and judicial regimes. Emerging from these developments are increases in environmental offences, and more recently environmental crimes. The judicial processing of environmental or ‘green’ crimes is rapidly developing across many jurisdictions. Since 1979, Australia has played a lead role in criminal justice processing of environment offences through the New South Wales Land and Environment Court (NSW LEC). This article draws on case data, observations and interviews with court personnel, to examine the ways in which environmental justice is now administered through the existing court structures, and how it has changed since the Court’s inception.