38 resultados para Tool life


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Machining of titanium is quite difficult and expensive. Heat generated in the process of cutting does not dissipate quickly, which affects tool life. In the last decade ultra fine grained (UFG) titanium has emerged as an option for substitution for more expensive titanium alloys. Extreme grain refinement can be readily performed by severe plastic deformation techniques. Grain refinement of a material achieved in this way was shown to change its mechanical and physical properties. In the present study, the microstructure evolution and the shear band formation in chips of coarse grained and UFG titanium machined to three different depths and three different feeding rates was investigated. A change in thermal characteristics of commercial purity Ti with grain refinement was studied by comparing heating/cooling measurements with an analytical solution of the heat transfer boundary problem. It was demonstrated that an improvement in the machinability can be expected for UFG titanium. © 2012 Springer Science+Business Media, LLC.

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The research aim is to study and analyze the shear zone by application of merchant circle during machining of titanium alloy (Ti6Al4V). The thermo-mechanical reaction during machining plays an important role in defining machinability of titanium alloys. The scientific community is concerned about machining of titanium alloy due to problems occurring in the shear zone that affect tool life. Studying the cutting action contributes to understanding and addressing these problems effectively. For this purpose, an experimental setup, utilizing a high speed camera will be used to study the shear zone. The shear zone characteristics are studied by analyzing the images captured by a high speed camera placed near to the shear zone during machining. The experimental design consists of conducting a series of turning trials using combination of cutting parameters namely constant spindle speed (n) 770 rpm; feed rate (f) of 2 and 4 mm/rev; and depth of cut (d) of 1 and 2 mm. The length of cut (L) of 10 mm remains constant and no coolant is used for all trials. The images obtained from the camera are analyzed against the theory of orthogonal cutting using merchants circle.

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The significant effects of the building industry on the natural environment are well documented and improving the environmental performance of buildings is an on-going challenge. This is particularly the case for projects with restrictive budgets and timelines and because many existing environmental assessment tools are designed to be used too late in the design process. The use of tools during the early design stages may assist in achieving greater improvements in a building’s environmental performance. However, user-friendly tools with the ability to comprehensively compare environmental information between various building assemblies and materials, which can be easily adopted during the early design stages of a project, are not readily available. This paper presents the progress to date in developing a tool which supports building designers in identifying and selecting preferred building assemblies with the aim of minimising a building’s life cycle energy demand. The tool is based on comprehensive energy performance data for a broad range of building assemblies across all Australian climate zones. Allowing for adjustments to a set of pre-defined and user-defined assemblies the designer is able to see how assemblies perform in relation to each other. This provides valuable information to support decision-making relating to minimising the life cycle energy demand of buildings.

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The quality of life of caregivers of patients with cancer is an important construct given the substantial impact of caring on the physical, psychological, social, and financial well-being of caregivers. Moreover, caring for patients with cancer also affects family functioning and places burdens on caregivers. The reliability and validity of instruments used to assess the quality of life of caregivers of patients with cancer were reviewed to aid in the selection of the most appropriate measures For research and practice. MEDLINE (1980-2000) and c/NAHL (1982-2000) searches located relevant quality of life instruments using the keywords "cancer and quality of Iife" and "caregiver or spouse or partner." The search identified the following instruments: the Caregiver Quality of life Index-Cancer Scale, the 'Caregiver Quality of Life Index, the Quality of Life Tool, and the Quality of life Index-Cancer Version. Quality of life instruments developed specifically to measure the quality of life of caregivers of patients with cancer had the best psychometric properties. The Caregiver Quality of Life Index-Cancer Scale, in particular, met or exceeded minimum psychometric criteria for reliability and validity. The development of reliable and valid caregiver quality of life measures is an important factor in developing interventions to enhance quality of life of caregivers of patients with cancer.

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Life-cycle assessment (LCA) is a technique that is used worldwide by clients and their design team to assess the impact of
their projects on the environment. The main advantage of LCA is in supporting decision making with quantitative data. LCA inventories
can be either fully developed or streamlined. Fully developed LCAs are time-consuming and costly to prepare. Streamlined LCAs can be
used as an effective decision-making tool when considering environmental performance during the design process, but with a loss of
inventory completeness. Acknowledging the advantages and disadvantages of both types of LCA, this paper proposes a hybrid LCA
method that uses input-output data to fill in those gaps routinely left in conventional LCA inventories.

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The aims of this study are (1) to establish a reliable and valid quality-of-life (QOL) questionnaire for Chinese patients with head and neck (H&N) cancer who are treated with radiation therapy and (2) to evaluate the impact of the immediate side effects of treatment on the QOL of these patients. The 39-item "Quality of Life Radiation Therapy Instrument with Head and Neck Companion Module" (QOL-RTI/H&N) was translated into Chinese. In the reliability evaluation phase (study module 1), the questionnaire was administered twice to 56 H&N cancer patients, 7 days apart, during the second and third week of radiation therapy. In the validity evaluation phase (study module 2), 138 patients completed the QOL-RTI/H&N before starting and at the end of radiation therapy. Sixty-nine of these 138 patients also completed the QOL-RTI/H&N during the second week of their radiation therapy, at the same time as completing the Functional Assessment of Cancer Therapy-Head and Neck (FACT-H&N) questionnaire. Cronbach alpha coefficients were 0.88 for the general-tool QOL-RTI and 0.90 for the H&N subscale. Test-retest reliability was satisfactory with intraclass correlation coefficients of 0.89 for the general-tool QOL-RTI and 0.75 for the H&N subscale. The instrument can discriminate between patients with stage I or II disease and those with stage III or IV disease (P < .05). Concurrent validity was established by the good agreement with the FACT-H&N (r = 0.86, P < .001). A highly significant deterioration was in the QOL from the baseline to the end of treatment (mean difference for general tool = 1.95, P < .001; mean difference for H&N subscale = 4.85, P < .001). The Chinese QOL-RTI/H&N is a reliable and valid tool for determining the QOL in H&N cancer patients receiving radiation therapy. The immediate side effects of treatment had a significantly negative impact on the patients' QOL. The impact was relatively large for the functional and treatment-site aspects.

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Objective: To evaluate the psychometric properties of the World Health Organization Quality of Life short version instrument (WHOQOL-BREF), and to determine its responsiveness in assessing early outcome after total hip or knee replacement surgery.

Methods:
At baseline (entry to an orthopedic waiting list), 279 participants completed the WHOQOL-BREF instrument, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Assessment of Quality of Life (AQOL) instrument, Kessler Psychological Distress (K10) scale, and the modified Health Assessment Questionnaire (MHAQ). A total of 74 patients completed reassessments 3 months after surgery.

Results: The WHOQOL-BREF demonstrated acceptable internal consistency for all domains (Cronbach's = 0.76-0.84) and moderate concurrent validity for the physical and psychological domains (r = 0.67 for physical versus AQOL; r = -0.71 for psychological versus K10). Minimal ceiling or floor effects were identified at baseline or 3 months, except for the social relationships domain. The disease-specific WOMAC subscales were most responsive to change (relative efficiency [RE] 0.66-1.00). Apart from social relationships, all WHOQOL-BREF scores improved significantly after surgery. The physical domain was more responsive than the AQOL (RE 0.50 versus 0.42) and was similar to the MHAQ (RE 0.55 for MHAQ). The responsiveness of the psychological domain was similar to that of the K10 scale (RE 0.11 versus 0.08).

Conclusion: The WHOQOL-BREF has good psychometric properties for use in persons with severe joint disease, and by providing complementary information, it offers clinicians and researchers an additional tool for comprehensively assessing quality of life in this patient group.

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Background: Patient education and self-management programs are offered in many countries to people with chronic conditions such as osteoarthritis (OA). The most well-known is the disease-specific Stanford Arthritis Self-Management Program (ASMP). While Australian and international clinical guidelines promote the concept of self-management for OA, there is currently little evidence to support the use of the ASMP. Several meta-analyses have reported that arthritis self-management programs had minimal or no effect on reducing pain and disability. However, previous studies have had methodological shortcomings including the use of outcome measures which do not accurately reflect program goals. Additionally, limited cost-effectiveness analyses have been undertaken and the cost-utility of the program has not been explored.

Methods/design: This study is a randomised controlled trial to determine the efficacy (in terms of Health-Related Quality of Life and self-management skills) and cost-utility of a 6-week group-based Stanford ASMP for people with hip or knee OA.

Six hundred participants referred to an orthopaedic surgeon or rheumatologist for hip or knee OA will be recruited from outpatient clinics at 2 public hospitals and community-based private practices within 2 private hospital settings in Victoria, Australia. Participants must be 18 years or over, fluent in English and able to attend ASMP sessions. Exclusion criteria include cognitive dysfunction, previous participation in self-management programs and placement on a waiting list for joint replacement surgery or scheduled joint replacement.

Eligible, consenting participants will be randomised to an intervention group (who receive the ASMP and an arthritis self-management book) or a control group (who receive the book only). Follow-up will be at 6 weeks, 3 months and 12 months using standardised self-report measures. The primary outcome is Health-Related Quality of Life at 12 months, measured using the Assessment of Quality of Life instrument. Secondary outcome measures include the Health Education Impact Questionnaire, Western Ontario and McMaster Universities Osteoarthritis Index (pain subscale and total scores), Kessler Psychological Distress Scale and the Hip and Knee Multi-Attribute Priority Tool. Cost-utility analyses will be undertaken using administrative records and self-report data. A subgroup of 100 participants will undergo qualitative interviews to explore the broader potential impacts of the ASMP.

Discussion:
Using an innovative design combining both quantitative and qualitative components, this project will provide high quality data to facilitate evidence-based recommendations regarding the ASMP.

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The impacts on the environment from human activities are of increasing concern. The need to consider the reduction in energy consumption is of particular interest, especially in the construction and operation of buildings, which accounts for between 30 and 40% of Australia's national energy consumption. Much past and more recent emphasis has been placed on methods for reducing the energy consumed in the operation of buildings. With the energy embodied in these buildings having been shown to account for an equally large proportion of a building's life cycle energy consumption, there is a need to look at ways of reducing the embodied energy of buildings and related products. Life cycle assessment (LCA) is considered to be the most appropriate tool for assessing the life cycle energy consumption of buildings and their products. The life cycle inventory analysis (LCIA) step of a LCA, where an inventory of material and energy inputs is gathered, may currently suffer from several limitations, mainly concerned with the use of incomplete and unreliable data sources and LCIA methods. These traditional methods of LCIA include process-based and input-output-based LCIA. Process-based LCIA uses process specific data, whilst input-output-based LCIA uses data produced from an analysis of the flow of goods and services between sectors of the Australian economy, also known as input-output data. With the incompleteness and unreliability of these two respective methods in mind, hybrid LCIA methods have been developed to minimise the errors associated with traditional LCIA methods, combining both process and input-output data. Hybrid LCIA methods based on process data have shown to be incomplete. Hybrid LCIA methods based on input-output data involve substituting available process data into the input-output model minimising the errors associated with process-based hybrid LCIA methods. However, until now, this LCIA method had not been tested for its level of completeness and reliability. The aim of this study was to assess the reliability and completeness of hybrid life cycle inventory analysis, as applied to the Australian construction industry. A range of case studies were selected in order to apply the input-output-based hybrid LCIA method and evaluate the subsequent results as obtained from each case study. These case studies included buildings: two commercial office buildings, two residential buildings, a recreational building; and building related products: a solar hot water system, a building integrated photovoltaic system and a washing machine. The range of building types and products selected assisted in testing the input-output-based hybrid LCIA method for its applicability across a wide range of product types. The input-output-based hybrid LCIA method was applied to each of the selected case studies in order to obtain their respective embodied energy results. These results were then evaluated with the use of a number of evaluation methods. These evaluation methods included an analysis of the difference between the process-based and input-output-based hybrid LCIA results as an evaluation of the completeness of the process-based LCIA method. The second method of evaluation used was a comparison between equivalent process and input-output values used in the input-output-based hybrid LCIA method as a measure of reliability. It was found that the results from a typical process-based LCIA and process-based hybrid LCIA have a large gap when compared to input-output-based hybrid LCIA results (up to 80%). This gap has shown that the currently available quantity of process data in Australia is insufficient. The comparison between equivalent process-based and input-output-based LCIA values showed that the input-output data does not provide a reliable representation of the equivalent process values, for material energy intensities, material inputs and whole products. Therefore, the use of input-output data to account for inadequate or missing process data is not reliable. However, as there is currently no other method for filling the gaps in traditional process-based LCIA, and as input-output data is considered to be more complete than process data, and the errors may be somewhat lower, using input-output data to fill the gaps in traditional process-based LCIA appears to be better than not using any data at all. The input-output-based hybrid LCIA method evaluated in this study has shown to be the most sophisticated and complete currently available LCIA method for assessing the environmental impacts associated with buildings and building related products. This finding is significant as the construction and operation of buildings accounts for a large proportion of national energy consumption. The use of the input-output-based hybrid LCIA method for products other than those related to the Australian construction industry may be appropriate, especially if the material inputs of the product being assessed are similar to those typically used in the construction industry. The input-output-based hybrid LCIA method has been used to correct some of the errors and limitations associated with previous LCIA methods, without the introduction of any new errors. Improvements in current input-output models are also needed, particularly to account for the inclusion of capital equipment inputs (i.e. the energy required to manufacture the machinery and other equipment used in the production of building materials, products etc.). Although further improvements in the quantity of currently available process data are also needed, this study has shown that with the current available embodied energy data for LCIA, the input-output-based hybrid LCIA appears to provide the most reliable and complete method for use in assessing the environmental impacts of the Australian construction industry.

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Aims. This study sought to measure the rates and trajectory of depression over six months following admission for an acute cardiac event and describe the relationship between depression and life satisfaction.
Background. Co-morbid depression has an impact on cardiac mortality and is associated with the significant impairment of quality of life and well-being, impairments in psychosocial function, decreased medication adherence and increased morbidity.
Design. This was a descriptive, correlational study.
Method. The study was undertaken at a large public hospital in Melbourne. Participants were asked to complete a survey containing the cardiac depression scale (CDS) and the Personal Well-being Index.
Results. This study mapped the course of depression over six months of a cohort of patients admitted for an acute cardiac event. Significant levels of depressive symptoms were found, at a level consistent with the literature. A significant correlation between depressive symptoms as measured by the CDS and the Personal Well-being Index was found.
Conclusions. Depression remains a significant problem following admission for an acute coronary event. The Personal Wellbeing Index may be a simple, effective and non-confrontational initial screening tool for those at risk of depressive symptoms in this population. Relevance to clinical practice. Despite the known impact of depression on coronary heart disease (CHD), there is limited research describing its trajectory. This study makes a compelling case for the systematic screening for depression in patients with CHD and the importance of the nursing role in identifying at risk individuals.

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This thesis reveals that context can be used as a tool to explore the connections, interpretations and meanings individuals assign to their existence and unique constructions of reality. Effective and transformative environmental education is dependent on a deeper understanding and examination of these unique existential and contextual forces.

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The paper provides a brief description of the tool for evaluating the quality and utilisation of academic library spaces (TEALS). Supported by Deakin University Library, TEALS has been developed out of a research project in the School of Architecture and Building, Deakin University, Geelong Waterfront Campus. The tool is intended to establish the setting for evaluation of physical spaces at different phases of development of new academic library spaces and refurbishment of existing ones as well as throughout the life of buildings. The methodological framework of the tool consists of four key elements; establishing Criteria of Quality (CoQ), determining Quality Indicators, evaluating library spaces against QIs and interpreting results for future improvements. The characteristics that distinguish TEALS from existing evaluation models include adopting an approach that focus on people (students, faculty and library staff), acting as a “reflective” and “empowering” tool and being user-friendly, quick and easy to use.

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This paper examines the “Respect for History” project on Turkey's Gallipoli Peninsula sponsored by a Turkish oil company, OPET. The project sought to enhance and protect the cultural and historical experiences of tourists visiting Gallipoli, and to bring direct and indirect benefits to local communities through enhancing tourism-related business opportunities and improving community infrastructure. This research investigates the project's impact on residents’ perceived social and economic wellbeing, using a quality of life framework, and also ascertains residents’ views of the sponsoring firm. The context illustrates key differences between pure philanthropy and strategic philanthropy; the latter defined as doing good by purposefully achieving corporate and civic benefits. The role of strategic philanthropy as a sustainable tourism development tool, and its impact on tourism governance, are considered. Data were collected from 674 residents on the Turkish Gallipoli Peninsula in areas impacted by OPET's investment program. The results, using structural equation modelling (SEM), identify that respondents generally believe that both their economic and social quality of life have improved. This, in turn, has positively influenced respondents’ views of the sponsoring organization. The concept of strategic philanthropy appears valuable as a private sector, non-tourism, sustainable tourism development tool in some circumstances.

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Background : The Beck Depression Inventory (BDI) is one of the most commonly used instruments to assess depression in persons with obesity. While it has been validated in normal and psychiatric populations, in obese populations, its validity remains uncertain. This study aimed to investigate the validity and reliability of the BDI-IA and BDI-II in severely obese bariatric surgery candidates.

Methods : Consecutive new candidates at a bariatric surgery clinic were invited to participate in the study by their consulting surgeon. All candidates were assessed using the Structured Clinical Interview for DSM-IV Disorders (SCID-I); 118 completed the BDI-IA and 83 completed the BDI-II. Two hundred one patients (response rate, 88 %) participated in the study. The current sample (82 % female) had an average body mass index of 42.83 ± 6.34 and an average age of 45 ± 12 years.

Results : Based on the SCID-I, 54 candidates (26.9 %) met the criteria for a mood disorder, with 37 meeting the criteria for current major depressive disorder. Individuals diagnosed with a clinical mood disorder had significantly higher scores on the BDI (BDI-IA, 23.59 ± 9.69 vs. 12.76 ± 8.29; BDI-II, 22.93 ± 5.22 vs. 11.25 ± 8.44). Our results indicated that, as a screening tool for a clinical mood disorder, the BDI-II had an optimal cutoff of 13, with a sensitivity of 100 and specificity of 67.75.

Conclusions : Results indicated that the BDI-IA should not be used as a tool to measure depressive symptomatology in obese bariatric surgery candidates. No cutoff was identified with adequate sensitivity and specificity, and over 20 % of patients were misclassified. As a screening tool for a clinical mood disorder, the BDI-II was adequate; however, prevalence rates were significantly overestimated.

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OBJECTIVE To develop a linguistically and psychometrically validated U.K. English (U.K./Ireland) version of the Diabetes-Specific Quality-of-Life Scale (DSQOLS) for adults with type 1 diabetes.

RESEARCH DESIGN AND METHODS We conducted independent forward and backward translation of the validated German DSQOLS. An iterative interview study with health professionals (n = 3) and adults with type 1 diabetes (n = 8) established linguistic validity. The DSQOLS was included in three Dose Adjustment for Normal Eating (DAFNE) studies (total N = 1,071). Exploratory factor analysis (EFA) was undertaken to examine questionnaire structure. Concurrent and discriminant validity, internal consistency, and reliability were assessed.

RESULTS EFA indicated a six-factor structure for the DSQOLS (social aspects, fear of hypoglycemia, dietary restrictions, physical complaints, anxiety about the future, and daily hassles). High internal consistency reliability was found for these factors and the weighted treatment satisfaction scale (α = 0.85–0.94). All subscales were moderately, positively correlated with the Audit of Diabetes-Dependent Quality-of-Life (ADDQoL) measure, demonstrating evidence of concurrent validity. Lower DSQOLS subscale scores [indicating impaired quality of life (QoL)] were associated with the presence of diabetes-related complications.

CONCLUSIONS The DSQOLS captures the impact of detailed aspects of modern type 1 diabetes management (e.g., carbohydrate counting and flexible insulin dose adjustment) that are now routine in many parts of the U.K. and Ireland. The U.K. English version of the DSQOLS offers a valuable tool for assessing the impact of treatment approaches on QoL in adults with type 1 diabetes.