35 resultados para Frane Appenniniche Back analysis colate stabilizzazione versanti

em Deakin Research Online - Australia


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Some of the geotechnical parameters used in the analysis may not be accurately measured directly from laboratory tests due to effects of sample disturbance and errors of tests. The back analysis or the observational method are thus often applied to determine the representative and/or dominant strength parameters based on field observations in practice. Based on the Hoek-Brown failure criterion, it was known that the disturbance factor (D) should be determined with caution. The difficulty of measuring rock mass disturbance accurately has been shown. Three rock slope failures will be investigated in this paper using back-analysis technique. In addition, various rock mass strength parameters are taken into consideration.

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It is known that rock masses are inhomogeneous, discontinuous media composed of rock material and naturally occurring discontinuities such as joints, fractures and bedding planes. These features make any analysis very difficult using simple theoretical solutions. Generally speaking, back analysis technique can be used to capture some implicit parameters for geotechnical problems. In order to perform back analyses, the procedure of trial and error is generally required. However, it would be time-consuming. This study aims at applying a neural network to do the back analysis for rock slope failures. The neural network tool will be trained by using the solutions of finite element upper and lower bound limit analysis methods. Therefore, the uncertain parameter can be obtained, particularly for rock mass disturbance.

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The analysis of rock slope stability is a classical problem for geotechnical engineers. However, for practicing engineers, proper software is not usually user friendly, and additional resources capable of providing information useful for decision-making are required. This study developed a convenient tool that can provide a prompt assessment of rock slope stability. A nonlinear input-output mapping of the rock slope system was constructed using a neural network trained by an extreme learning algorithm. The training data was obtained by using finite element upper and lower bound limit analysis methods. The newly developed techniques in this study can either estimate the factor of safety for a rock slope or obtain the implicit parameters through back analyses. Back analysis parameter identification was performed using a terminal steepest descent algorithm based on the finite-time stability theory. This algorithm not only guarantees finite-time error convergence but also achieves exact zero convergence, unlike the conventional steepest descent algorithm in which the training error never reaches zero.

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The advent of the World Wide Web (WWW) and the emergence of Internet commerce have given rise to the web as a medium of information exchange. In recent years, the phenomenon has affected the realm of transaction processing systems, as organizations are moving from designing web pages for marketing purposes, to web-based applications that support business-to-business (WEB) and business-to-consumer (B2C) interactions, integrated with databases and other back-end systems (Isakowitz, Bieber et al., 1998). Furthermore, web-enabled applications are increasingly being used to facilitate transactions even between various business units within a single enterprise. Examples of some of the more popular web-enabled applications in use today include airline reservation systems, internet banking, student enrollment systems in universities, and Human Resource (HR) and payroll systems. The prime motive behind the adoption of web-enabled applications are productivity gains due to reduced processing time, decrease in the usage of paper-based documentation and conventional modes of communication (such as letters, fax, or telephone), and improved quality of services to clients. Indeed, web-based solutions are commonly referred to as customer-centric (Li, 2000), which means that they provide user interfaces that do not necessitate high level of computer proficiency. Thus, organizations implement such systems to streamline routine transactions and gain strategic benefits in the process (Nambisan & Wang, 1999), though the latter are to be expected in the long-term. Notwithstanding the benefits of web technology adoption, the web has ample share of challenges for initiators and developers. Many of these challenges are associated with the unique nature of web-enabled applications. Research in the area of web-enabled information systems has revealed several differences with traditional applications. These differences exist with regards to system development methodology, stakeholder involvement, tasks, and technology (Nazareth, 1998). According to Fraternali (1999), web applications are commonly developed using an evolutionary prototyping approach, whereby the simplified version of the application is deployed as a pilot first, in order to gather user feedback. Thus, web-enabled applications typically undergo continuous refinement and evolution (Ginige, 1998; Nazareth, 1998; Siau, 1998; Standing, 2001). Prototype-based development also leads web-enabled information systems to have much shorter development life cycles, but which, unlike traditional applications, are regrettably developed in a rather adhoc fashion (Carstensen & Vogelsang, 2001). However, the principal difference between the two kinds of applications lies in the broad and diverse group of stakeholders associated with web-based information systems (Gordijn, Akkermans, et al., 2000; Russo, 2000; Earl & Khan, 2001; Carter, 2002; Hasselbring, 2002; Standing, 2002; Stevens & Timbrell, 2002). Stakeholders, or organizational members participating in a common business process (Freeman, 1984), vary in their computer competency, business knowledge, language and culture. This diversity is capable of causing conflict between different stakeholder groups with regards to the establishment of system requirements (Pouloudi & Whitley, 1997; Stevens & Timbrell, 2002). Since, web-based systems transcend organizational, departmental, and even national boundaries, the issue of culture poses a significant challenge to the web systems’ initiators and developers (Miles & Snow, 1992; Kumar & van Dissel, 1996; Pouloudi & Whitley, 1996; Li & Williams, 1999).

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Objective To evaluate the effectiveness of a population based, state-wide public health intervention designed to alter beliefs about back pain, influence medical management, and reduce disability and costs of compensation. Design Quasi-experimental, non-randomised, non-equivalent, before and after telephone surveys of the general population and postal surveys of general practitioners with an adjacent state as control group and descriptive analysis of claims database. Setting Two states in Australia Participants 4730 members of general population before and two and two and a half years after campaign started, in a ratio of2:1:1; 2556 general practitioners before and two years after campaign onset. Main outcome measures Back beliefs questionnaire, knowledge and attitude statements about back pain, incidence of workers' financial compensation claims for back problems, rate of days compensated, and medical payments for claims related to back pain and other claims. Results In the intervention state beliefs about back pain became more positive between successive surveys (mean improvement in questionnaire score 1.9 (95% confidence interval 1.3 to 2.5), P<0.001 and 3.2 (2.6 to 3.9), P < 0.001, between baseline and the second and third survey, respectively). Beliefs about back pain also improved among doctors. There was a clear decline in number of claims for back pain, rates of days compensated, and medical payments for claims for back pain over the duration of the campaign. Conclusions A population based strategy of provision of positive messages about back pain improves population and general practitioner beliefs about back pain and seems to influence medical management and reduce disability and workers' compensation costs related to back pain.

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Wrought magnesium alloys exhibit poor cold formability and the accepted explanation is the shortage of independent slip systems. In order to improve the formability in these alloys, an understanding of the deformation modes is required. In the present work, activation of different slip and twinning systems are investigated in rolled Mg–3Al–1Zn using electron back scattering diffraction. Analysis was performed on deformed surfaces and on metallographically prepared cross-sections following deformation at room temperature. The results reinforce the importance of prismatic slip and c-axis compression double twinning.

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In Australia, male sports attendees outnumber female sports attendees by 25%, yet little research has been conducted into the attendance motives of women. This study undertakes an analysis of 460 respondents using descriptive and multivariate statistics to distinguish the attendance motivations of women and compare them directly to those of male attendees. The findings suggest that female attendance can be influenced through management and promotional strategies.

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With the continually evolving social nature of information systems research there is a need to identify different “modes of analysis” (Myers, 1997) to uncover our understanding of the complex, messy and often chaotic nature of human factors. One suggested mode of analysis is that of social dramas, a tool developed in the anthropological discipline by Victor Turner. The use of social dramas also utilises the work by Goffman (1959; 1997) and enables the researcher to investigate events from the front stage, reporting obvious issues in systems implementation, and from the back stage, identifying the hidden aspects of systems implementation and the underpinning discourses. A case study exploring the social dramas involved in systems selection and implementation has been provided to support the use of this methodological tool.

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We designed and implemented a traffic accident analysis system (TAAS) in the paper. TAAS is the system faced traffic accident analysis, which uses the traffic rules (law) as knowledge sources to judge if the driver is responsible for a traffic accident. TAAS has characteristics of separating knowledge base and inference engine, using production rule and backward chaining. Besides, TAAS used predefined text and tracing program to realize explanation mechanism.

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Drawing on Michel Foucault’s later genealogies of the Self the paper will illustrate particular dimensions of the increasingly powerful individualizing and normalizing processes shaping the lifeworlds of worker-citizens in a globalizing risk society. Processes that require those who wish to be positively identified as professional, entrepreneurial, resilient, effective, athletic to do particular sorts of work on themselves. Here the paper argues that we can identify the emergence of what we call New Work Ethics. We illustrate this more general argument via an analysis of the ways in which a large Information Technology (IT) organization seeks to produce—via a workplace health and fitness program—employees who imagine themselves as embodying the behaviours and dispositions that mark the person as a corporate athlete. Knowledge of the Self in these terms can, it is promised, enhance the performance of the Self, and the organization.

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Electron back-scattered diffraction in conjunction with transmission electron microscopy was employed to investigate the crystallographic nature of bainitic laths formed at relatively low transformation temperatures where a nanostructured bainite forms. It was revealed that the bainitic ferrite laths are close to the Nishiyama–Wasserman orientation relationship with the parent austenite. Furthermore, the temperature showed a significant effect on the retained austenite characteristics and the variant selection of the bainitic ferrite laths. A decrease in temperature generally refined the bainitic structure and weakened the variant selection.

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The development and use of cocycles for analysis of non-autonomous behaviour is a technique that has been known for several years. Initially developed as an extension to semi-group theory for studying rion-autonornous behaviour, it was extensively used in analysing random dynamical systems [2, 9, 10, 12]. Many of the results regarding asymptotic behaviour developed for random dynamical systems, including the concept of cocycle attractors were successfully transferred and reinterpreted for deterministic non-autonomous systems primarily by P. Kloeden and B. Schmalfuss [20, 21, 28, 29]. The theory concerning cocycle attractors was later developed in various contexts specific to particular classes of dynamical systems [6, 7, 13], although a comprehensive understanding of cocycle attractors (redefined as pullback attractors within this thesis) and their role in the stability of non-autonomous dynamical systems was still at this stage incomplete. It was this purpose that motivated Chapters 1-3 to define and formalise the concept of stability within non-autonomous dynamical systems. The approach taken incorporates the elements of classical asymptotic theory, and refines the notion of pullback attraction with further development towards a study of pull-back stability arid pullback asymptotic stability. In a comprehensive manner, it clearly establishes both pullback and forward (classical) stability theory as fundamentally unique and essential components of non-autonomous stability. Many of the introductory theorems and examples highlight the key properties arid differences between pullback and forward stability. The theory also cohesively retains all the properties of classical asymptotic stability theory in an autonomous environment. These chapters are intended as a fundamental framework from which further research in the various fields of non-autonomous dynamical systems may be extended. A preliminary version of a Lyapunov-like theory that characterises pullback attraction is created as a tool for examining non-autonomous behaviour in Chapter 5. The nature of its usefulness however is at this stage restricted to the converse theorem of asymptotic stability. Chapter 7 introduces the theory of Loci Dynamics. A transformation is made to an alternative dynamical system where forward asymptotic (classical asymptotic) behaviour characterises pullback attraction to a particular point in the original dynamical system. This has the advantage in that certain conventional techniques for a forward analysis may be applied. The remainder of the thesis, Chapters 4, 6 and Section 7.3, investigates the effects of perturbations and discretisations on non-autonomous dynamical systems known to possess structures that exhibit some form of stability or attraction. Chapter 4 investigates autonomous systems with semi-group attractors, that have been non-autonomously perturbed, whilst Chapter 6 observes the effects of discretisation on non-autonomous dynamical systems that exhibit properties of forward asymptotic stability. Chapter 7 explores the same problem of discretisation, but for pullback asymptotically stable systems. The theory of Loci Dynamics is used to analyse the nature of the discretisation, but establishment of results directly analogous to those discovered in Chapter 6 is shown to be unachievable. Instead a case by case analysis is provided for specific classes of dynamical systems, for which the results generate a numerical approximation of the pullback attraction in the original continuous dynamical system. The nature of the results regarding discretisation provide a non-autonomous extension to the work initiated by A. Stuart and J. Humphries [34, 35] for the numerical approximation of semi-group attractors within autonomous systems. . Of particular importance is the effect on the system's asymptotic behaviour over non-finite intervals of discretisation.

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This study investigates the influences on participation in physical activity of thirty adolescent girls from a metropolitan secondary school in Victoria. It seeks to understand how they perceived, experienced and explained their involvement or non involvement in both competitive and non competitive physical activity during four years of their secondary schooling. Participants experienced physical education as both a single sex group in Years 7 and 9 and a coeducational group in Years 8 and 10. They were exposed to a predominantly competitive curriculum in Years 7 to 9 and a less structured, more social, recreational program in Year 10. These experiences enabled them to compare the differences between class structures and activity programs and identify the significant issues which impacted on their participation. Large Australian population studies have revealed that fewer girls participated in sport and regular physical activity than boys. An important consequence is that girls miss out on the health benefits associated with participating in physical activity. Other research has found adolescence is the time that girls drop out of competitive sport. However, an important issue is whether girls who drop out of competitive sport cease to be involved in any physical activity. There are some studies which have reported good participation rates by adolescent girls in non competitive, recreational forms of physical activity and the possibility exists that they may drop out of competitive and into non competitive physical activity. This study primarily utilises a qualitative approach in contrast to previous studies which have largely relied upon the use of surveys and questionnaires. Whilst quantitative research has provided useful information about the bigger picture, there are limitations caused by reliance on the researchers' own interpretations of the data. Additionally there is no opportunity for any clarification and explanation of findings and trends by the respondents themselves. The current study utilized qualitative individual and collective interviews in three stages. Questions were asked in the broad areas of coeducation and single sex classes, preferences for competitive or recreational activity and body image issues. Some quantitative information focusing on nature and extent of current activity patterns was also gathered in the first stage. Thirty Year 10 girls participated in individual first interviews. Nine selected girls then took part in the second (individual) and third (collective) interview stages. Results revealed three groups based on the nature of physical activity involvement: [1] competitive activity group, [2] social activity group and [3] transition group. The transition group represented those who were in the process of withdrawing from competitive sport to take up more non competitive, recreational activity. The most significant difference between groups was skill level. On the whole those entering adolescence with the highest skill levels, such as those in the competitive group, were the most confident and relished competing against others. The social group was low in skill and confidence and had predominantly negative experiences in physical education and sport because their deficiencies were plainly visible to all. Similarly, a lack of skill improvement relative to those of 'better performers' affected the interest and confidence levels of those in the transition group. Boys' domination in coeducational classes through verbal and physical intimidation of the less competent and confident girls and exclusion of very competent girls was a major issue. Social and transition group members demonstrated compliance with boys' power by hanging back and sitting out of competitive activities. Conversely, the competitive group resisted boy's attempts to dominate but had to work hard to demonstrate their athletic capabilities in order to do so. Body image issues such as the skimpy physical education and sport uniform along with body revealing activities such as swimming and gymnastics, heightened feelings of self-consciousness and embarrassment for most girls. When strategies were adopted by social and transition group members to avoid any body exposure or physical humiliation, participation levels were subsequently affected. However, where girls felt confident about their physical abilities and body image, they were able to ignore their unflattering uniforms and thus participation was unaffected. Specific teaching practices such as giving more attention to boys, for example by segregating the sexes in mixed classes to focus attention on boys, reinforced stereotypical notions of gender and contributed to the inequities for girls in physical education. The competitive group were frustrated with having to prove themselves as capable as boys in order to receive greater teacher attention. The transition group rejected teacher's attempts to coerce them into participating in the inter school sports program. The social group believed that teachers viewed and treated them less favourably than others because of their limited skills. Girls were not passive in the face of these obstacles. Rather than give up physical activity they disengaged from competitive sport and took up other forms of activity which they had the confidence to perform. These activity choices also reflected their expanding social interests such as spending time with male and female friends outside school and increased demands on their time by study and part time work commitments. This study not only highlighted the diversity and complexity of attitudes and behaviours of girls towards physical activity but also demonstrated that they display agency in making conscious, sensible decisions about their physical activity choices. Plain Language Summary of Thesis Adolescent girls in physical education and sport; An analysis of influences on participation by Julia Whitty Submitted for the degree of Master of Applied Science Deakin University Supervisor: Dr Judy Ann Jones This study investigates the influences on participation in physical activity of thirty adolescent girls from a metropolitan secondary school in Victoria in order to understand how girls' perceived, experienced and explained their involvement or non involvement in both competitive and non competitive physical activity. Qualitative individual and collective interviews were conducted. Questions focussed on attitudes about coeducation and single sex classes, preferences for competitive or recreational activity and feelings about body image. Some quantitative information about the nature and extent of current activity patterns was also gathered in the first stage. Thirty Year 10 girls participated in individual first interviews. Nine selected girls then took part in the second (individual) and third (collective) interview stages. Results revealed three clearly different groups based on the nature of physical activity involvement (1) Competitive, (2) Social and (3) Transition (those in the process of withdrawing from competitive sport to take up more non competitive, recreational activity). The major difference between groups was skill level. Those entering adolescence with the highest skill levels were more competent and confident in the coeducational and competitive sport setting. Other significant issues included boys' domination, body image and teaching behaviours and practices.

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Headteacher workloads are often in the news. Long hours, punitive audit regimes and excessive amounts of paperwork take their toll on many, including John Illingworth, former National Union of Teachers (UK) President, and ex primary headteacher. In this paper, I investigate a UK BBC Radio 4 human interest interview conducted with Illingworth by the usually acerbic John Humphrys. Mobilising Bourdieu’s notion of field, I examine the interview and argue that the analysis suggests that the media game of market share and the doxa of the fourth estate might work to delimit the capacity of such interviews to speak truth to policy power.