65 resultados para Parallel design patterns


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Permanent magnet synchronous machines (PMSMs) are popular in both industrial and domestic applications because of its high efficiency, power density, and reliability as compared with the conventional types of electrical machines. Generally, the analytical models and their field solutions are preferable to provide an accurate insight of the PMSM performances, instead of using the finite element models, because the former takes a considerably shorter computational time. PMSM design could have different properties of either slotted or slotless, or varieties of magnet placement on the rotor. By focusing on semi-closed surface-mounted PMSMs, the 2D analytical subdomain model in [1] demonstrates an accurate prediction of the magnetic fields that can facilitate the evaluation of the global quantities of PMSMs, such as cogging torque (Tcog), back-EMF, and total harmonic distortion (THDv). Previously, researchers investigated the influences of the machine performance by a single factor, e.g., the variation of Tcog during changes of magnet pole-arc (αP) [2, 3], or slot-opening [2, 3]. These investigations normally considered two types of magnetization patterns, i.e., parallel (PaM) and radial magnetization (RM). Therefore, the motivation of our work hinges on predicting the optimum value of αP in designing a surface-mounted PMSM under influence of four different magnetization patterns, using the analytical subdomain model.

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Objective: This study investigated 5-year trends in body weight, overweight and obesity and their association with sociodemographic variables in a large, multi-ethnic community sample of Australian adults.  Design: This prospective population study used baseline and 5-year follow-up data from participants in the Melbourne Collaborative Cohort Study (MCCS). Setting: Population study in Melbourne, Australia. Subjects: In total, 12 125 men and 17 674 women aged 35–69 years at baseline. Results: Mean 5-year weight change in this sample was +1.58 (standard deviation (SD) 4.82) kg for men and +2.42 (SD 5.17) kg for women. Younger (35–44 years) men and, in particular, women gained more weight than older adults and were at highest risk of major weight gain ($5 kg) and becoming overweight. Risk of major weight gain and associations between demographic variables and weight change did not vary greatly by ethnicity. Education level showed complex associations with weight outcomes that differed by sex and ethnicity. Multivariate analyses showed that, among men, higher initial body weight was associated with decreased likelihood of major weight gain, whereas among women, those initially overweight or obese were about 20% more likely to experience major weight gain than underweight or healthy weight women. Conclusions: Findings of widespread weight gain across this entire population sample, and particularly among younger women and women who were already overweight, are a cause for alarm. The prevention of weight gain and obesity across the entire population should be an urgent public health priority. Young-to-mid adulthood appears to be a critical time to intervene to prevent future weight gain.

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Objective: The aim of this study is to evaluate the consistency of dietary patterns assessed through the use of a dietary recall and a 5-day food diary. Design: Participants (n=2265) of a longitudinal study of health and development completed 48-h dietary recall at interview, followed by a 5-day food diary and with the 24 h immediately preceding the interview analysed separately as a 24-h recall. Mean intakes of foods and nutrients were calculated and dietary patterns were assessed using exploratory factor analysis, using the method of principal components. Paired t-tests and correlation coefficients were used to compare the three dietary assessment methods. Results: Five distinct dietary patterns were identified using the food diary and the 48-h recall but were less consistent on the 24-h recall.  Correlations between factor scores on the 48-h recall and the food diary (r=0.13–0.67) were higher than those between the 24-h recall and food diary (r=-0.01–0.59). The recall methods were effective at ranking subjects according to food and nutrient intakes, with the 48-h recall and food diary showing higher correlations in both males and females. Conclusions: This study indicates that a 48-h recall effectively characterises dietary patterns in British adults when compared to a food diary and ranks participants appropriately with respect to most nutrients and foods and is superior to a single 24-h recall. These results have implications for longitudinal studies where maximising response rates to repeat dietary assessment tools is essential.

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Based on an analysis of a corpus of forty of Sir Edwin Lutyens's country house designs (Rollo 1997) a procedure for developing Parallel Descriptions will be discussed. This procedure will attempt to facilitate an integrated approach to the analysis of complex architectural forms and will provide a framework for investigating the development of parallel grammars. This is an approach which acknowledges that design does not necessarily involve the importance of one aspect, but rather a number of coextensive issues with emphasis on the ordering and priority of these issues periodically shifting.

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The emergence of the global ecological crisis is presenting unique opportunities for the coordination of ethical thinking across cultural boundaries. Harm minimization as an ethical imperative operates as the ‘modus operandi’ behind both Ecologically Sustainable Design (ESD) and Buddhist practice. The architectural response to ESD is founded upon the ‘Declaration of Interdependence for a Sustainable Future’ adopted in 1993 by the International Union of Architects, of which the RAIA is a member.

Buddhism is a response to existential concerns universal to humanity. It developed as a set of principles for personal transformation known as the Four Noble Truths elucidated two and a half thousand years ago. Buddhist meditation practise ‘interrupts automatic patterns of conditioned behaviour’ recognised as the major obstacle to be overcome in any programme for change. Unsustainable egocentric behaviour is considered fundamental to our global ecological crisis and calls for radical behavioural change are increasingly being heard at the professional as well as the personal level. Emerging synergies between the Western cognitive sciences and Buddhist study of the mind increasingly validate the Tibetan Buddhist mind development phenomenon. Buddhists argue that their programme for enhancing ethical behaviour through mind development is a step-by step process of observation and analysis built upon empirical observation – a fundamental pre-requisite of any ‘scientific’ enquiry. Collaborative research programmes currently underway are an attempt to re-interpret Buddhist meditation techniques within a framework acceptable to Western scientific understanding. A truly holistic approach to harm minimization requires its consideration.

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The aim of this paper is to show a general design of autonomic elements and initial implementation of a cluster operating system that moves parallel processing on clusters to the computing mainstream using the autonomic computing vision. The significance of this solution is as follows. Autonomic Computing was identified by IBM as one of computing's Grand Challenges. The human body was used to illustrate an Autonomic Computing system that possesses self-knowledge, self-configuration, self optimization, self-healing, and self-protection, knowledge of its environment and user friendliness properties. One of the areas that could benefit from the comprehensive approach created by the autonomic computing vision is parallel processing on non-dedicated clusters. Many researchers and research groups have responded positively to the challenge by initiating research around one or two of the characteristics identified by IBM as the requirements for autonomic computing. We demonstrate here that it is possible to satisfy all Autonomic Computing characteristics.

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Parallel file systems offer improved performance over traditional file systems by allowing processes to access file data, stored over a number of disks, in parallel. When this file is to be accessed by many processes at the same time for reading and writing, the problem of maintaining file consistency is introduced. The general approach to maintaining file consistency is through the use locks which grant a single process exclusive access to the file. Existing studies have found parallel file systems and associated applications rarely experience conflict, resulting in unnecessary overheads from locks being acquired. This paper examines an alternate approach to maintaining file consistency, which is based on optimistic concurrency control. This approach was shown to have a much smaller overhead when compared with traditional lock-based approaches; especially in situations when there is little contention. This paper presents the design, implementation and initial testing results of an optimistic based concurrency control mechanism.

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The paper describes some details of the mechanical and kinematics design of a five-axis mechanism. The design has been utilized to physically realize an industrial-scale five-axis milling machine that can carry a three KW spindle. However, the mechanism could be utilized in other material processing and factory automation applications. The mechanism has five rectilinear joints/axes. Two of these axes are arranged traditionally, i.e. in series, and the other three axes utilize the concept of parallel kinematics. This combination results in a design that allows three translational and two rotational two-mode degrees of freedom (DOFs). The design provides speed, accuracy and cost advantages over traditional five-axis machines. All axes are actuated using linear motors.

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Objectives: This study aimed 10 evaluate the food intake pattens of adolescents with respect to the Australian Guide to Healthy Eating, and to examine variations in food intake patterns by age, gender and region of residence.
Design: Cross-sectional online food survey administered through schools. Participants and setting: In 2004-2005,3841 secondary students in years seven (12-13 years) and nine (14-15 years) drawn from 37 secondary schools in Victoria, Australia completed an online food intake patterns survey.
Outcome measures: Food intake was measured by a Food Frequency Questionnaire (FFQ), and categorized according to the five basic food groups (fruit, vegetables, meat, daily, cereal) and the 'extra' food group as defined by the Australian Guide to Healthy Eating (AGHE). The foods groups were examined in the study population and compared across age, gender and region.
Results: Many adolescents in this sample reported food intakes that deviated substantially from recommendations of the AGHE. For example, two-thirds of participants failed to consume foods from the five recommended food groups daily; over a third reported eating fruit 'rarely or never'; and 22% reported eating fast foods every day. Food intakes were generally more in line with dietary guidelines among girls than boys.
Regional differences were less consistent, and there were few differences by age.
Conclusion: A significant proportion of adolescents have food intakes that fall short of the recommendations outlined in the Australian Guide to Healthy Eating. This highlights the need for public health initiatives to promote healthier food intake pattens among adolescents.

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Objective: To describe dietary patterns among men and women in the Australian population, and to explore how these varied according to socioeconomic status (SES).

Design: A cross-sectional self-report population survey, the 1995 Australian National Nutrition Survey (NNS), was used.

Setting: Private dwelling sample, covering urban and rural areas across Australia.

Subjects: Data provided by 6680 adults aged 18-64 who participated in the NNS were used in the analyses.

Methods: Factor analyses were used to analyse data from a Food Frequency Questionnaire (FFQ) completed by participants. Associations between SES and dietary pattens were assessed using ANOVA.

Results:
Separate factor analyses of the FFQ data for men and women revealed 15 factors, accounting for approximately 50% of the variance in both men's and women's dietary patterns. Several gender and SES differences in food patterns were observed. Lower SES males more frequently consumed 'tropical fruits', 'protein foods', and 'offal and canned fish', while high SES males more often ate 'breakfast cereals' and 'wholemeal bread'. Lower SES females more often ate 'traditional vegetables', 'meat dishes' and 'pasta, rice and other mixed foods', while high SES females more frequently ate 'ethnic vegetables' and 'breakfast cereal/muesli'.

Conclusions: These findings contribute to a better understanding of the dietary patterns that underscore gender-specific SES differences in nutrient intakes. Analyses of the type employed in this study will facilitate the development of interventions aimed at modifying overall eating patterns, rather than specific components of the diet.


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OBJECTIVE—We examined the associations of objectively measured sedentary time and physical activity with continuous indexes of metabolic risk in Australian adults without known diabetes.

RESEARCH DESIGN AND METHODS—An accelerometer was used to derive the percentage of monitoring time spent sedentary and in light-intensity and moderate-to-vigorous–intensity activity, as well as mean activity intensity, in 169 Australian Diabetes, Obesity and Lifestyle Study (AusDiab) participants (mean age 53.4 years). Associations with waist circumference, triglycerides, HDL cholesterol, resting blood pressure, fasting plasma glucose, and a clustered metabolic risk score were examined.

RESULTS—Independent of time spent in moderate-to-vigorous–intensity activity, there were significant associations of sedentary time, light-intensity time, and mean activity intensity with waist circumference and clustered metabolic risk. Independent of waist circumference, moderate-to-vigorous–intensity activity time was significantly beneficially associated with triglycerides.

CONCLUSIONS—These findings highlight the importance of decreasing sedentary time, as well as increasing time spent in physical activity, for metabolic health.

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This thesis provides an examination of the work of instructional designers in distance education, through the conceptual lens of chaos theory. Chaos theory was chosen as an analytical tool because of its ability to reveal the patterns and processes of complex systems as they move between order and turbulence. Recent work in the social sciences, specifically literary theory, has provided impetus for applications of chaos theory to educational settings. Specifically, chaos theory is used to analyse eight case studies of projects volunteered by instructional designers working in five institutions in Hong Kong and Australia. Data were gathered over a period of months with each participant, chiefly through interviews, but also involving diary accounts, electronic mail and letters. The methodology was thus qualitative, specifically informed by Eisner's vision of the ‘critical connoisseur’. Eisner equates an ‘enlightened eye’ with attainment of the skills of a critical connoisseur. First, an effective qualitative researcher must develop connoisseurship, the art of appreciation. On its own, though, connoisseurship is not enough; it is a private act, and thus needs a public face or presence. Criticism is this link, criticism being the art of disclosure. The critical connoisseur aims to help others to increase perception and deepen understanding of an educational situation or event. In addition to the empirical work, a parallel strand of this thesis investigates the theory and reported practice of instructional design. A brief history of instructional design is presented, along with discussion of acknowledged deficiencies of current theory and approaches. Recent reported investigations of both theory and practice are analysed from the viewpoint of chaos theory. Examination of key contributions in the literature of instructional design and distance education reveals considerable resonance between these contributions and the fundamental properties of chaotic systems. Links are made, in both the theoretical and empirical strands, between instructional design and the behaviour of dissipative structures, attractors and the process of bifurcation. Use is also made of the time-dependent nature of chaos theory as a theory of becoming, rather than one of being. The thesis comprises eight chapters, two appendices and a references section. The introductory chapter explains the research problem, and outlines the structure of the thesis. Methodological considerations are left until after an assessment of instructional design literature and (reported) practice. This deliberately theoretical investigation (Chapters 2 and 3) comprises the first of the parallel strands that are presented. The basic conclusions are that instructional design theory has not been particularly helpful to or used by instructional designers, and that chaos theory might provide an alternative way of viewing instructional design practice. The other parallel strand is the empirical work, which for four chapters outlines the methodology and my findings concerning the role of instructional designers in distance education. The methodology is detailed in Chapter 4. Chapter 5 establishes the contexts of the participants, by examining their backgrounds and introductions to their roles. It also investigates their views on their role and status within their institutions and with working colleagues. Chapter 6 is an exploration of the major issues that influenced the work of the instructional designers. These are the issues that arose naturally in the interviews as the participants outlined the development and interactions that took place on a day to day basis. Time emerges as a key influence in their work, and its effects on the projects are outlined and analysed. The ways that instructional designers give advice to those with whom they work is also investigated. The next chapter continues consideration of their work, but this time as they reflect on their role and its demands. This includes their reactions to the various metaphors that have appeared in the literature, along with those that they introduced into our discussions. The links that are established between the two parallel strands are drawn more explicitly in the final chapter, Chapter 8, which is a notion of what a model of instructional design based on my conclusions might resemble. It summarises the evidence that it is not necessarily by striving for order—in fact quite the opposite — during key periods of course development, that leads to creative outcomes. The introduction of uncertainty and turbulence does, in some cases and under some conditions, move the system to a higher level. The image that is offered from chaos theory is that of time-bound dissipative structures, interacting with their open environment at far-from-equilibrium conditions, and transforming themselves from disorder to order through bifurcation. The role of strange or chaotic attractors is highlighted in the process. The first appendix gives background information in terms of the methodology. The second is the heart of the data upon which the thesis draws. That is, the second appendix outlines the case studies of the participants. Most are short summaries, but the final one is a detailed study, tracing the progress of the design and development of a subject in distance education.

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Current attempts to manage parallel applications on Clusters of Workstations (COWs) have either generally followed the parallel execution environment approach or been extensions to existing network operating systems, both of which do not provide complete or satisfactory solutions. The efficient and transparent management of parallelism within the COW environment requires enhanced methods of process instantiation, mapping of parallel process to workstations, maintenance of process relationships, process communication facilities, and process coordination mechanisms. The aim of this research is to synthesise, design, develop and experimentally study a system capable of efficiently and transparently managing SPMD parallelism on a COW. This system should both improve the performance of SPMD based parallel programs and relieve the programmer from the involvement into parallelism management in order to allow them to concentrate on application programming. It is also the aim of this research to show that such a system, to achieve these objectives, is best achieved by adding new special services and exploiting the existing services of a client/server and microkernel based distributed operating system. To achieve these goals the research methods of the experimental computer science should be employed. In order to specify the scope of this project, this work investigated the issues related to parallel processing on COWs and surveyed a number of relevant systems including PVM, NOW and MOSIX. It was shown that although the MOSIX system provide a number of good services related to parallelism management, none of the system forms a complete solution. The problems identified with these systems include: instantiation services that are not suited to parallel processing; duplication of services between the parallelism management environment and the operating system; and poor levels of transparency. A high performance and transparent system capable of managing the execution of SPMD parallel applications was synthesised and the specific services of process instantiation, process mapping and process interaction detailed. The process instantiation service designed here provides the capability to instantiate parallel processes using either creation or duplication methods and also supports multiple and group based instantiation which is specifically design for SPMD parallel processing. The process mapping service provides the combination of process allocation and dynamic load balancing to ensure the load of a COW remains balanced not only at the time a parallel program is initialised but also during the execution of the program. The process interaction service guarantees to maintain transparently process relationships, communications and coordination services between parallel processes regardless of their location within the COW. The combination of these services provides an original architecture and organisation of a system that is capable of fully managing the execution of SPMD parallel applications on a COW. A logical design of a parallelism management system was developed derived from the synthesised system and was shown that it should ideally be based on a distributed operating system employing the client server model. The client/server based distributed operating system provides the level of transparency, modularity and flexibility necessary for a complete parallelism management system. The services identified in the synthesised system have been mapped to a set of server processes including: Process Instantiation Server providing advanced multiple and group based process creation and duplication; Process Mapping Server combining load collection, process allocation and dynamic load balancing services; and Process Interaction Server providing transparent interprocess communication and coordination. A Process Migration Server was also identified as vital to support both the instantiation and mapping servers. The RHODOS client/server and microkernel based distributed operating system was selected to carry out research into the detailed design and to be used for the implementation this parallelism management system. RHODOS was enhanced to provide the required servers and resulted in the development of the REX Manager, Global Scheduler and Process Migration Manager to provide the services of process instantiation, mapping and migration, respectively. The process interaction services were already provided within RHODOS and only required some extensions to the existing Process Manager and IPC Managers. Through a variety of experiments it was shown that when this system was used to support the execution of SPMD parallel applications the overall execution times were improved, especially when multiple and group based instantiation services are employed. The RHODOS PMS was also shown to greatly reduce the programming burden experienced by users when writing SPMD parallel applications by providing a small set of powerful primitives specially designed to support parallel processing. The system was also shown to be applicable and has been used in a variety of other research areas such as Distributed Shared Memory, Parallelising Compilers and assisting the port of PVM to the RHODOS system. The RHODOS Parallelism Management System (PMS) provides a unique and creative solution to the problem of transparently and efficiently controlling the execution of SPMD parallel applications on COWs. Combining advanced services such as multiple and group based process creation and duplication; combined process allocation and dynamic load balancing; and complete COW wide transparency produces a totally new system that addresses many of the problems not addressed in other systems.

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The majority of women's health nurses in this study work in generalist community health centres. They have developed their praxis within the philosophy and policies of the broader women's health movement and primary health care principles in Australia. The fundamental assumption underlying this study is that women's health nurses possess a unique body of knowledge and clinical wisdom that has not been previously documented and explored. The epistemological base from which these nurses' operate offers important insights into the substantive issues that create and continually shape the practice world of nurses and their clients. Whether this represents a (re)construction of the dominant forms of health care service delivery for women is examined in this study. The study specifically aims at exploring the practice issues and experience of women's health service provision by women's health nurses in the context of the provision of cervical cancer screening services. In mapping this particular group of nurses practice, it sets out to examine the professional and theoretical issues in contemporary nursing and women's health care. In critically analysing the powerful discourses that shape and reshape nursing work, the study raises the concern that previous analyses of pursing work tend to universalise the structural and social subordination of nurses and nursing knowledge. This universalism is most often based on examples of midwifery and nursing work in hospital settings, and subsequently, because of these conceptualisations, all of nursing is too often deemed as a dependent occupation, with little agency, and is analysed as always in relation to medicine, to hospitals, to other knowledge forms. Denoting certain discourses as dominant proposes a relationship of power and knowledge and the thesis argues that all work relations and practices in health are structured by certain power/knowledge relations. This analysis reveals that there IX are many competing and complimentary power/knowledge relations that structure nursing, but that nursing, and in particular women's health nurses, also challenge the power/knowledge relations around them. Through examining theories of power and knowledge the analysis, argues that theoretical eclecticism is necessary to address the complex and varied nature of nursing work. In particular it identifies that postmodern and radical feminist theorising provide the most appropriate framework to further analyse and interpret the work of women's health nurses. Fundamental to the position argued in this thesis is a feminist perspective. This position creates important theoretical and methodological links throughout the whole study. Feminist methodology was employed to guide the design, the collection and the analysis. Intrinsic to this process was the use of the 'voices' of women's health nurses as the basis for theorising. The 'voices' of these nurses are highlighted in the chapters as italicised bold script. A constant companion along the way in examining women's health nurses' work, was the reflexivity with feminist research processes, the theoretical discussions and their 'voices'. Capturing and analysing descriptive accounts of nursing praxis is seen in this thesis as providing a way to theorise about nursing work. This methodology is able to demonstrate the knowledge forms embedded in clinical nursing praxis. Three conceptual threads emerge throughout the discussions: one focuses on nursing praxis as a distinct process, with its own distinct epistemological base rather than in relation to 'other' knowledge forms; another describes the medical restriction and opposition as experienced by this group of nurses, but also of their resistance to medical opposition. The third theme apparent from the interviews, and which was conceptualised as beyond resistance, was the description of the alternative discourses evident in nursing work, and this focused on notions of being a professional and on autonomous nursing praxis. This study concludes that rather than accepting the totalising discourses about nursing there are examples within nursing of resistance—both ideologically and X in practice—to these dominant discourses. Women's health nurses represent an important model of women's health service delivery, an analysis of which can contribute to critically reflecting on the 'paradigm of oppression' cited in nursing and about nursing more generally. Reflecting on women's health service delivery also has relevance in today's policy environment, where structural shifts in Commonwealth/State funding arrangements in community based care, may undermine women's health programs. In summary this study identifies three important propositions for nursing: • nursing praxis can reconstruct traditional models of health care; • nursing praxis is powerful and able to 'resist' dominant discourses; and • nursing praxis can be transformative. Joining feminist perspectives and alternative analyses of power provides a pluralistic and emancipatory politics for viewing, describing and analysing 'other' nursing work. At the micro sites of power and knowledge relations—in the everyday practice worlds of nurses, of negotiation and renegotiation, of work on the margins and at the centre—women's health nurses' praxis operates as a positive, productive and reconstructive force in health care.

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The aim of the work was to reduce the cost and improve the performance of five-axis machines. The main performance criteria were motion cycle-time and positioning accuracy/precision. A novel machine that utilizes the concept of parallel-kinematics and linear motor technology is proposed, designed, built and controlled for this sake.