840 resultados para LCA, life cycle assessment, LCC, life cycle cost


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A generic, hierarchical, and multifidelity unit cost of acquisition estimating methodology for outside production machined parts is presented. The originality of the work lies with the method’s inherent capability of being able to generate multilevel and multifidelity cost relations for large volumes of parts utilizing process, supply chain costing data, and varying degrees of part design definition information. Estimates can be generated throughout the life cycle of a part using different grades of the combined information available. Considering design development for a given part, additional design definition may be used as it becomes available within the developed method to improve the quality of the resulting estimate. Via a process of analogous classification, parts are classified into groups of increasing similarity using design-based descriptors. A parametric estimating method is then applied to each subgroup of the machined part commodity in the direction of improved classification and using which, a relationship which links design variables to manufacturing cycle time may be generated. A rate cost reflective of the supply chain is then applied to the cycle time estimate for a given part to arrive at an estimate of make cost which is then totalled with the material and treatments cost components respectively to give an overall estimate of unit acquisition cost. Both the rate charge applied and the treatments cost calculated for a given procured part is derived via the use of ratio analysis.

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Background: SPARCLE is a cross-sectional survey in nine European regions, examining the relationship of the environment of children with cerebral palsy to their participation and quality of life. The objective of this report is to assess data quality, in particular heterogeneity between regions, family and item non-response and potential for bias. Methods: 1,174 children aged 8–12 years were selected from eight population-based registers of children with cerebral palsy; one further centre recruited 75 children from multiple sources. Families were visited by trained researchers who administered psychometric questionnaires. Logistic regression was used to assess factors related to family non-response and self-completion of questionnaires by children. Results: 431/1,174 (37%) families identified from registers did not respond: 146 (12%) were not traced; of the 1,028 traced families, 250 (24%) declined to participate and 35 (3%) were not approached. Families whose disabled children could walk unaided were more likely to decline to participate. 818 children entered the study of which 500 (61%) self-reported their quality of life; children with low IQ, seizures or inability to walk were less likely to self-report. There was substantial heterogeneity between regions in response rates and socio-demographic characteristics of families but not in age or gender of children. Item non-response was 2% for children and ranged from 0.4% to 5% for questionnaires completed by parents. Conclusion: While the proportion of untraced families was higher than in similar surveys, the refusal rate was comparable. To reduce bias, all analyses should allow for region, walking ability, age and socio-demographic characteristics. The 75 children in the region without a population based register are unlikely to introduce bias

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A methodology to estimate the cost implications of design decisions by integrating cost as a design parameter at an early design stage is presented. The model is developed on a hierarchical basis, the manufacturing cost of aircraft fuselage panels being analysed in this paper. The manufacturing cost modelling is original and relies on a genetic-causal method where the drivers of each element of cost are identified relative to the process capability. The cost model is then extended to life cycle costing by computing the Direct Operating Cost as a function of acquisition cost and fuel burn, and coupled with a semi-empirical numerical analysis using Engineering Sciences Data Unit reference data to model the structural integrity of the fuselage shell with regard to material failure and various modes of buckling. The main finding of the paper is that the traditional minimum weight condition is a dated and sub-optimal approach to airframe structural design.

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The purpose of this study is to develop a decision making system to evaluate the risks in E-Commerce (EC) projects. Competitive software businesses have the critical task of assessing the risk in the software system development life cycle. This can be conducted on the basis of conventional probabilities, but limited appropriate information is available and so a complete set of probabilities is not available. In such problems, where the analysis is highly subjective and related to vague, incomplete, uncertain or inexact information, the Dempster-Shafer (DS) theory of evidence offers a potential advantage. We use a direct way of reasoning in a single step (i.e., extended DS theory) to develop a decision making system to evaluate the risk in EC projects. This consists of five stages 1) establishing knowledge base and setting rule strengths, 2) collecting evidence and data, 3) determining evidence and rule strength to a mass distribution for each rule; i.e., the first half of a single step reasoning process, 4) combining prior mass and different rules; i.e., the second half of the single step reasoning process, 5) finally, evaluating the belief interval for the best support decision of EC project. We test the system by using potential risk factors associated with EC development and the results indicate that the system is promising way of assisting an EC project manager in identifying potential risk factors and the corresponding project risks.

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Objectives: To examine whether any response shift in quality of life assessment over the course of a cardiac rehabilitation programme could be explained by changes in individuals’ internal standards (recalibration), values (reprioritization) and/or conceptualization of quality of life and the extent to which any response shift could be explained by health locus of control, optimism and coping strategy. Design: Longitudinal survey design. Methods: The SEIQoL-DW was administered at the beginning and end of a cardiac rehabilitation programme. At the end of the programme, the SEIQoL-DW then-test was also administered to measure response shift. A total of 57 participants completed these measures and other measures to assess health locus of control, optimism and coping. Results: Response shift effects were observed in this population mainly due to recalibration. When response shift was incorporated into the analysis of QoL a larger treatment effect was observed. Active coping as a mechanism in the response shift model was found to have a significant positive correlation with response shift. Conclusion: This study showed that response shift occurs during cardiac rehabilitation. The occurrence of response shift in QoL ratings over time for this population could have implications for the estimation of the effectiveness of the intervention.

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Advances in stem cell science and tissue engineering are being turned into applications and products through a novel medical paradigm known as regenerative medicine. This paper begins by examining the vulnerabilities and risks encountered by the regenerative medicine industry during a pivotal moment in its scientific infancy: the 2000s. Under the auspices of New Labour, British medical scientists and life science innovation firms associated with regenerative medicine, received demonstrative rhetorical pledges of support, aligned with the publication of a number of government initiated reports presaged by Bioscience 2015: Improving National Health, Increasing National Wealth. The Department of Health and the Department of Trade and Industry (and its successors) held industry consultations to determine the best means by which innovative bioscience cultures might be promoted and sustained in Britain. Bioscience 2015 encapsulates the first chapter of this sustainability narrative. By 2009, the tone of this storyline had changed to one of survivability. In the second part of the paper, we explore the ministerial interpretation of the ‘bioscience discussion cycle’ that embodies this narrative of expectation, using a computer-aided content analysis programme. Our analysis notes that the ministerial interpretation of these reports has continued to place key emphasis upon the distinctive and exceptional characteristics of the life science industries, such as their ability to perpetuate innovations in regenerative medicine and the optimism this portends – even though many of the economic expectations associated with this industry have remained unfulfilled.

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Gymnogongrus sp. (Phyllophoraceae) from Nova Scotia, Canada, identified tentatively as G. devoniensis (Greville) Schotter, grows in association with an Erythrodermis-like crust that forms chains of tetrasporangia or bisporangia. The crust resembles tetrasporophytic phases of other Gymnogongrus species, but in culture both it and the G. ?devoniensis gametophytes cycle independently by apomictic reproduction.

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The objective of this research was to determine the surface temperature of a high pressure die casting die during casting conditions. This was achieved by instrumentation of an insert which was placed in the shotplate region of the die. This research overcame the challenge of directly measuring the die surface temperature during a HPDC production casting cycle and shows that this is an effective method to determine the die surface temperature during the casting cycle. The instrumentation results gave a peak and minimum temperature of 500 C and 240 C respectively during steady state running conditions with a molten aluminium casting temperature of 660 C. Stress analysis from the steady state measured temperature of the die surface was calculated through a simple FEA model and the resulting stress uctuation was applied to a fatigue equation for the die material, the predicted number of cycles for cracking to start was found to correlate well with observed die damage.

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Objective: To evaluate the impact of a provider initiated primary care outreach intervention compared with usual care among older adults at risk of functional decline. Design: Randomised controlled trial. Setting: Patients enrolled with 35 family physicians in five primary care networks in Hamilton, Ontario, Canada. Participants Patients: were eligible if they were 75 years of age or older and were not receiving home care services. Of 3166 potentially eligible patients, 2662 (84%) completed the validated postal questionnaire used to determine risk of functional decline. Of 1724 patients who met the risk criteria, 769 (45%) agreed to participate and 719 were randomised. Intervention: The 12 month intervention, provided by experienced home care nurses in 2004-6, consisted of a comprehensive initial assessment using the resident assessment instrument for home care; collaborative care planning with patients, their families, and family physicians; health promotion; and referral to community health and social support services. Main outcome measures: Quality adjusted life years (QALYs), use and costs of health and social services, functional status, self rated health, and mortality. Results: The mean difference in QALYs between intervention and control patients during the study period was not statistically significant (0.017, 95% confidence interval -0.022 to 0.056; P=0.388). The mean difference in overall cost of prescription drugs and services between the intervention and control groups was not statistically significant, (-$C165 (£107; €118; $162), 95% confidence interval -$C16 545 to $C16 214; P=0.984). Changes over 12 months in functional status and self rated health were not significantly different between the intervention and control groups. Ten patients died in each group. Conclusions: The results of this study do not support adoption of this preventive primary care intervention for this target population of high risk older adults. Trial registration: Clinical trials NCT00134836.

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Background: Increasing emphasis is being placed on the economics of health care service delivery - including home-based palliative care. Aim: This paper analyzes resource utilization and costs of a shared-care demonstration project in rural Ontario (Canada) from the public health care system's perspective. Design: To provide enhanced end-of-life care, the shared-care approach ensured exchange of expertise and knowledge and coordination of services in line with the understood goals of care. Resource utilization and costs were tracked over the 15 month study period from January 2005 to March 2006. Results: Of the 95 study participants (average age 71 years), 83 had a cancer diagnosis (87%); the non-cancer diagnoses (12 patients, 13%) included mainly advanced heart diseases and COPD. Community Care Access Centre and Enhanced Palliative Care Team-based homemaking and specialized nursing services were the most frequented offerings, followed by equipment/transportation services and palliative care consults for pain and symptom management. Total costs for all patient-related services (in 2007 CAN) were 1,625,658.07 - or 17,112.19 per patient/117.95 per patient day. Conclusion: While higher than expenditures previously reported for a cancer-only population in an urban Ontario setting, the costs were still within the parameters of the US Medicare Hospice Benefits, on a par with the per diem funding assigned for long-term care homes and lower than both average alternate level of care and hospital costs within the Province of Ontario. The study results may assist service planners in the appropriate allocation of resources and service packaging to meet the complex needs of palliative care populations. © 2012 The Author(s).