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Highest Costs (highest + cost)
Selected AbstractsEnergy, exergy and exergoeconomic analysis of a steam power plant: A case studyINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 5 2009Mohammad Ameri Abstract The objective of this paper is to perform the energy, exergy and exergoeconomic analysis for the Hamedan steam power plant. In the first part of the paper, the exergy destruction and exergy loss of each component of this power plant is estimated. Moreover, the effects of the load variations and ambient temperature are calculated in order to obtain a good insight into this analysis. The exergy efficiencies of the boiler, turbine, pump, heaters and the condenser are estimated at different ambient temperatures. The results show that energy losses have mainly occurred in the condenser where 306.9,MW is lost to the environment while only 67.63,MW has been lost from the boiler. Nevertheless, the irreversibility rate of the boiler is higher than the irreversibility rates of the other components. It is due to the fact that the combustion reaction and its high temperature are the most significant sources of exergy destruction in the boiler system, which can be reduced by preheating the combustion air and reducing the air,fuel ratio. When the ambient temperature is increased from 5 to 24°C, the irreversibility rate of the boiler, turbine, feed water heaters, pumps and the total irreversibility rate of the plant are increased. In addition, as the load varies from 125 to 250,MW (i.e. full load) the exergy efficiency of the boiler and turbine, condenser and heaters are increased due to the fact that the power plant is designed for the full load. In the second part of the paper, the exergoeconomic analysis is done for each component of the power plant in order to calculate the cost of exergy destruction. The results show that the boiler has the highest cost of exergy destruction. In addition, an optimization procedure is developed for that power plant. The results show that by considering the decision variables, the cost of exergy destruction and purchase can be decreased by almost 17.11%. Copyright © 2008 John Wiley & Sons, Ltd. [source] Estimating personal costs incurred by a woman participating in mammography screening in the National Breast and Cervical Cancer Early Detection Program,,CANCER, Issue 3 2008Donatus U. Ekwueme PhD Abstract BACKGROUND. The National Breast and Cervical Cancer Early Detection Program (NBCCEDP) covers the direct clinical costs of breast and cervical cancer screening and diagnostic follow-up for medically underserved, low-income women. Personal costs are not covered. In this report, the authors estimated personal costs per woman participating in NBCCEDP mammography screening by race/ethnicity and also estimated lifetime personal costs (ages 50-74 years). METHODS. A decision analysis model was constructed and parameterized by using empiric data from a retrospective cohort survey of mammography rescreening among women ages 50 years to 64 years who participated in the NBCCEDP. Data from 1870 women were collected from 1999 to 2000. The model simulated the flow of resources incurred by a woman participating in the NBCCEDP. The analysis was stratified by annual income into 2 scenarios: Scenario 1, <$10,000; and Scenario 2, from $10,000 to <$20,000. Sensitivity analyses were conducted to appraise uncertainty, and all costs were standardized to 2000 U.S. dollars. RESULTS. In Scenario 1, for all races/ethnicities, a woman incurred a 1-time cost of $17 and a discounted lifetime cost of $108 for 10 screens and $262 for 25 screens; in Scenario 2, these amounts were $31 and from $197 to $475, respectively. In both scenarios, a non-Hispanic white woman incurred the highest cost. The sensitivity analyses revealed that >70% of cost incurred was attributable to opportunity cost. CONCLUSIONS. Capturing and quantifying personal costs will help ascertain the total cost (ie, societal cost) of providing mammography screening to a medically underserved, low-income woman participating in a publicly funded cancer screening program and, thus, will help determine the true cost-effectiveness of such programs. Cancer 2008. Published 2008 by the American Cancer Society. [source] Statistical optimization of octree searchesCOMPUTER GRAPHICS FORUM, Issue 6 2008Rener Castro Abstract This work emerged from the following observation: usual search procedures for octrees start from the root to retrieve the data stored at the leaves. But as the leaves are the farthest nodes to the root, why start from the root? With usual octree representations, there is no other way to access a leaf. However, hashed octrees allow direct access to any node, given its position in space and its depth in the octree. Search procedures take the position as an input, but the depth remains unknown. This work proposes to estimate the depth of an arbitrary node through a statistical optimization of the average cost of search procedures. As the highest costs of these algorithms are obtained when starting from the root, this method improves on both the memory footprint by the use of hashed octrees, and execution time through the proposed optimization. [source] A cost-effectiveness analysis of four management strategies in the determination and follow-up of atypical squamous cells of undetermined significanceDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2005Alice A. Hughes M.S.P.H. Abstract Atypical squamous cells of undetermined significance (ASC-US) are the most common abnormal cytological result on Papanicolaou (Pap) smear. We analyzed four management strategies in a hypothetical cohort of women divided by age group: (1) immediate colposcopy, (2) repeat cytology after an ASC-US Pap smear result, (3) conventional Pap with reflex human papillomavirus (HPV) testing, and (4) liquid-based cytology with reflex HPV testing. Parameter variables were collected from previously published data. Strategies that included reflex HPV testing had the lowest overall costs for all age groups combined. Repeat Pap smears had the highest number of true positive results throughout all stages but also had the uppermost number of missed cancers and highest costs. Immediate colposcopy had the second highest overall costs and detected fewer true positive results than liquid-based cytology. Younger women (aged 18,24 yr) consistently had higher total costs for all strategies investigated. Using the incremental cost-effectiveness (CE) ratio, the immediate colposcopy strategy was more costly and less effective than liquid-based cytology and, therefore, was dominated. The incremental CE ratio was lowest for liquid-based cytology compared with conventional cytology and liquid-based cytology with reflex HPV testing was the most cost-effective strategy. Diagn. Cytopathol. 2005;32:125,132. © 2005 Wiley-Liss, Inc. [source] Costs by industry and diagnosis among musculoskeletal claims in a state workers compensation system: 1999,2004AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2010Kari K. Dunning PhD Abstract Background Musculoskeletal disorders (MSDs) are a tremendous burden on industry in the United States. However, there is limited understanding of the unique issues relating to specific industry sectors, specifically the frequency and costs of different MSDs. Methods Claim data from 1999 to 2004 from the Ohio Bureau of Workers' Compensation were analyzed as a function of industry sector (NAICS industry-sector categories) and anatomical region (ICD-9 codes). Results Almost 50% of the claims were lumbar spine (26.9%) or hand/wrist (21.7%). The majority of claims were from manufacturing (25.1%) and service (32.8%) industries. The industries with the highest average costs per claim were transportation, warehouse, and utilities and construction. Across industries, the highest costs per claim were consistently for the lumbar spine, shoulder, and cervical spine body regions. Conclusion This study provides insight into the severity (i.e., medical and indemnity costs) of MSDs across multiple industries, providing data for prioritizing of resources for research and interventions. Am. J. Ind. Med. 53:276,284, 2010. © 2009 Wiley-Liss, Inc. [source] | ||||||||||