WorldWideScience

Sample records for modelling lifetime cost

  1. LCP- LIFETIME COST AND PERFORMANCE MODEL FOR DISTRIBUTED PHOTOVOLTAIC SYSTEMS

    Science.gov (United States)

    Borden, C. S.

    1994-01-01

    The Lifetime Cost and Performance (LCP) Model was developed to assist in the assessment of Photovoltaic (PV) system design options. LCP is a simulation of the performance, cost, and revenue streams associated with distributed PV power systems. LCP provides the user with substantial flexibility in specifying the technical and economic environment of the PV application. User-specified input parameters are available to describe PV system characteristics, site climatic conditions, utility purchase and sellback rate structures, discount and escalation rates, construction timing, and lifetime of the system. Such details as PV array orientation and tilt angle, PV module and balance-of-system performance attributes, and the mode of utility interconnection are user-specified. LCP assumes that the distributed PV system is utility grid interactive without dedicated electrical storage. In combination with a suitable economic model, LCP can provide an estimate of the expected net present worth of a PV system to the owner, as compared to electricity purchased from a utility grid. Similarly, LCP might be used to perform sensitivity analyses to identify those PV system parameters having significant impact on net worth. The user describes the PV system configuration to LCP via the basic electrical components. The module is the smallest entity in the PV system which is modeled. A PV module is defined in the simulation by its short circuit current, which varies over the system lifetime due to degradation and failure. Modules are wired in series to form a branch circuit. Bypass diodes are allowed between modules in the branch circuits. Branch circuits are then connected in parallel to form a bus. A collection of buses is connected in parallel to form an increment to capacity of the system. By choosing the appropriate series-parallel wiring design, the user can specify the current, voltage, and reliability characteristics of the system. LCP simulation of system performance is site

  2. Lifetime costs of cerebral palsy

    DEFF Research Database (Denmark)

    Kruse, Marie; Michelsen, Susan Ishøy; Flachs, Esben Meulengracht

    2009-01-01

    This study quantified the lifetime costs of cerebral palsy (CP) in a register-based setting. It was the first study outside the US to assess the lifetime costs of CP. The lifetime costs attributable to CP were divided into three categories: health care costs, productivity costs, and social costs....... The population analyzed was retrieved from the Danish Cerebral Palsy Register, which covers the eastern part of the country and has registered about half of the Danish population of individuals with CP since 1950. For this study we analyzed 2367 individuals with CP, who were born in 1930 to 2000 and were alive...

  3. The lifetime cost of a magnetic refrigerator

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Bahl, Christian R.H.; Nielsen, Kaspar Kirstein

    2016-01-01

    The total cost of a 25 W average load magnetic refrigerator using commercial grade Gd is calculated using a numerical model. The price of magnetocaloric material, magnet material and cost of operation are considered, and all influence the total cost. The lowest combined total cost with a device...... lifetime of 15 years is found to be in the range $150-$400 depending on the price of the magnetocaloric and magnet material. The cost of the magnet is largest, followed closely by the cost of operation, while the cost of the magnetocaloric material is almost negligible. For the lowest cost device...... characteristics are based on the performance of a conventional A+++ refrigeration unit. In a rough life time cost comparison between the AMR device and such a unit we find similar costs, the AMR being slightly cheaper, assuming the cost of the magnet can be recuperated at end of life....

  4. The lifetime cost of a magnetic refrigerator

    CERN Document Server

    Bjørk, R; Nielsen, K K

    2016-01-01

    The total cost of a 25 W average load magnetic refrigerator using commercial grade Gd is calculated using a numerical model. The price of magnetocaloric material, magnet material and cost of operation are considered, and all influence the total cost. The lowest combined total cost with a device lifetime of 15 years is found to be in the range \\$150-\\$400 depending on the price of the magnetocaloric and magnet material. The cost of the magnet is largest, followed closely by the cost of operation, while the cost of the magnetocaloric material is almost negligible. For the lowest cost device, the optimal magnetic field is about 1.4 T, the particle size is 0.23 mm, the length of the regenerator is 40-50 mm and the utilization is about 0.2, for all device lifetimes and material and magnet prices, while the operating frequency vary as function of device lifetime. The considered performance characteristics are based on the performance of a conventional A$^{+++}$ refrigeration unit. In a rough life time cost comparis...

  5. Modeling lifetime costs and health outcomes attributable to secondhand smoke exposure at home among Korean adult women.

    Science.gov (United States)

    Lee, Jiyae; Han, Ah Ram; Choi, Dalwoong; Lim, Kyung-Min; Bae, SeungJin

    2017-05-17

    The aim of this research is to estimate lifetime costs and health consequences for Korean adult women who were exposed to secondhand smoke (SHS) at home. A Markov model was developed to project the lifetime healthcare costs and health outcomes of a hypothetical cohort of Korean women who are 40 years old and were married to current smokers. The Korean epidemiological data were used to reflect the natural history of SHS-exposed and non-exposed women. The direct healthcare costs (in 2014 US dollars) and quality-adjusted life years (QALYs) were annually discounted at 5% to reflect time preference. The time horizon of the analysis was lifetime and the cycle length was 1 year. Deterministic and probabilistic sensitivity analyses were conducted. In the absence of SHS exposure, Korean women will live 41.32 years or 34.56 QALYs before discount, which corresponded to 17.29 years or 15.35 QALYs after discount. The SHS-exposed women were predicted to live 37.91 years and 31.08 QALYs before discount and 16.76 years and 14.62 QALYs after discount. The estimated lifetime healthcare cost per woman in the SHS non-exposed group was US$11 214 before the discount and US$2465 after discount. The negative impact of SHS exposure on health outcomes and healthcare costs escalated as the time horizon increased, suggesting that the adverse impact of SHS exposure may have higher impact on the later part of the lifetime. The result was consistent across a wide range of assumptions. Life expectancy might underestimate the impact of SHS exposure on health outcomes, especially if the time horizon of the analysis is not long enough. Early intervention on smoking behaviour could substantially reduce direct healthcare costs and improve quality of life attributable to SHS exposure. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Benefits and costs of substance abuse treatment programs for state prison inmates: results from a lifetime simulation model.

    Science.gov (United States)

    Zarkin, Gary A; Cowell, Alexander J; Hicks, Katherine A; Mills, Michael J; Belenko, Steven; Dunlap, Laura J; Houser, Kimberly A; Keyes, Vince

    2012-06-01

    Reflecting drug use patterns and criminal justice policies throughout the 1990s and 2000s, prisons hold a disproportionate number of society's drug abusers. Approximately 50% of state prisoners meet the criteria for a diagnosis of drug abuse or dependence, but only 10% receive medically based drug treatment. Because of the link between substance abuse and crime, treating substance abusing and dependent state prisoners while incarcerated has the potential to yield substantial economic benefits. In this paper, we simulate the lifetime costs and benefits of improving prison-based substance abuse treatment and post-release aftercare for a cohort of state prisoners. Our model captures the dynamics of substance abuse as a chronic disease; estimates the benefits of substance abuse treatment over individuals' lifetimes; and tracks the costs of crime and criminal justice costs related to policing, adjudication, and incarceration. We estimate net societal benefits and cost savings to the criminal justice system of the current treatment system and five policy scenarios. We find that four of the five policy scenarios provide positive net societal benefits and cost savings to the criminal justice system relative to the current treatment system. Our study demonstrates the societal gains to improving the drug treatment system for state prisoners.

  7. The total lifetime costs of smoking

    DEFF Research Database (Denmark)

    Rasmussen, Gitte Susanne; Prescott, Eva; Sørensen, Thorkild I A;

    2004-01-01

    Net costs of smoking in a lifetime perspective and, hence, the economic interests in antismoking policies have been questioned. It has been proposed that the health-related costs of smoking are balanced by smaller expenditure due to shorter life expectancy.......Net costs of smoking in a lifetime perspective and, hence, the economic interests in antismoking policies have been questioned. It has been proposed that the health-related costs of smoking are balanced by smaller expenditure due to shorter life expectancy....

  8. Projected Lifetime Healthcare Costs Associated with HIV Infection

    DEFF Research Database (Denmark)

    Nakagawa, Fumiyo; Miners, Alec; Smith, Colette J

    2015-01-01

    computer simulation model to project the distribution of lifetime outcomes and costs of men-who-have-sex-with-men (MSM) infected with HIV in 2013 aged 30, over 10,000 simulations. We assumed a resource-rich setting with no loss to follow-up, and that standards and costs of healthcare management remain...... had been infected in 2013, then future lifetime costs relating to HIV care is likely to be in excess of £ 1 billion. It is imperative for investment into prevention programmes to be continued or scaled-up in settings with good access to HIV care services. Costs would be reduced considerably with use...

  9. Lifetime costs of colon and rectal cancer management in Canada.

    Science.gov (United States)

    Maroun, Jean; Ng, Edward; Berthelot, Jean-Marie; Le Petit, Christel; Dahrouge, Simone; Flanagan, William M; Walker, Hugh; Evans, William K

    2003-01-01

    Colorectal cancer is the second leading cause of cancer-related mortality among Canadians. We derived the direct health care costs associated with the lifetime management of an estimated 16,856 patients with a diagnosis of colon and rectal cancer in Canada in 2000. Information on diagnostic approaches, treatment algorithms, follow-up and care at disease progression was obtained from various databases and was integrated into Statistics Canada's Population Health Model (POHEM) to estimate lifetime costs. The average lifetime cost (in Canadian dollars) of managing patients with colorectal cancer ranged from $20,319 per case for TNM stage I colon cancer to $39,182 per case for stage III rectal cancer. The total lifetime treatment cost for the cohort of patients in 2000 was estimated to be over $333 million for colon and $187 million for rectal cancer. Hospitalization represented 65% and 61% of the lifetime costs of colon and rectal cancer respectively. Disease costing models can be important policy- relevant tools to assist in resource allocation. Our results highlight the importance of performing preoperative tests and staging in an ambulatory care setting, where possible, to achieve optimal cost efficiencies. Similarly, terminal care might be delivered more efficiently in the home environment or in palliative care units.

  10. Models for Battery Reliability and Lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G. H.; Neubauer, J.; Pesaran, A.

    2014-03-01

    Models describing battery degradation physics are needed to more accurately understand how battery usage and next-generation battery designs can be optimized for performance and lifetime. Such lifetime models may also reduce the cost of battery aging experiments and shorten the time required to validate battery lifetime. Models for chemical degradation and mechanical stress are reviewed. Experimental analysis of aging data from a commercial iron-phosphate lithium-ion (Li-ion) cell elucidates the relative importance of several mechanical stress-induced degradation mechanisms.

  11. The lifetime cost of a magnetic refrigerator

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Bahl, Christian R.H.; Nielsen, Kaspar Kirstein

    2016-01-01

    The total cost of a 25 W average load magnetic refrigerator using commercial grade Gd is calculated using a numerical model. The price of magnetocaloric material, magnet material and cost of operation are considered, and all influence the total cost. The lowest combined total cost with a device l...... characteristics are based on the performance of a conventional A+++ refrigeration unit. In a rough life time cost comparison between the AMR device and such a unit we find similar costs, the AMR being slightly cheaper, assuming the cost of the magnet can be recuperated at end of life....

  12. Cost-effectiveness of dronedarone and standard of care compared with standard of care alone: US results of an ATHENA lifetime model

    Directory of Open Access Journals (Sweden)

    Reynolds MR

    2013-01-01

    Full Text Available Matthew R Reynolds,1 Jonas Nilsson,2 Örjan Åkerborg,2 Mehul Jhaveri,3 Peter Lindgren2,41Beth Israel Deaconess Medical Center, VA Boston Healthcare System, Boston, MA, USA; 2OptumInsight, Stockholm, Sweden; 3sanofi-aventis Inc, Bridgewater, NJ, USA; 4Institute of Environmental Medicine, Karolinska Institute, Stockholm, SwedenBackground: The first antiarrhythmic drug to demonstrate a reduced rate of cardiovascular hospitalization in atrial fibrillation/flutter (AF/AFL patients was dronedarone in a placebo-controlled, double-blind, parallel arm Trial to assess the efficacy of dronedarone 400 mg bid for the prevention of cardiovascular Hospitalization or death from any cause in patiENts with Atrial fibrillation/atrial flutter (ATHENA trial. The potential cost-effectiveness of dronedarone in this patient population has not been reported in a US context. This study assesses the cost-effectiveness of dronedarone from a US health care payers’ perspective.Methods and results: ATHENA patient data were applied to a patient-level health state transition model. Probabilities of health state transitions were derived from ATHENA and published data. Associated costs used in the model (2010 values were obtained from published sources when trial data were not available. The base-case model assumed that patients were treated with dronedarone for the duration of ATHENA (mean 21 months and were followed over a lifetime. Cost-effectiveness, from the payers' perspective, was determined using a Monte Carlo microsimulation (1 million fictitious patients. Dronedarone plus standard care provided 0.13 life years gained (LYG, and 0.11 quality-adjusted life years (QALYs, over standard care alone; cost/QALY was $19,520 and cost/LYG was $16,930. Compared to lower risk patients, patients at higher risk of stroke (Congestive heart failure, history of Hypertension, Age ≥ 75 years, Diabetes mellitus, and past history of Stroke or transient ischemic attack (CHADS2 scores 3

  13. Lifetime costs of lung transplantation : Estimation of incremental costs

    NARCIS (Netherlands)

    VanEnckevort, PJ; Koopmanschap, MA; Tenvergert, EM; VanderBij, W; Rutten, FFH

    1997-01-01

    Despite an expanding number of centres which provide lung transplantation, information about the incremental costs of lung transplantation is scarce. From 1991 until 1995, in The Netherlands a technology assessment was performed which provided information about the incremental costs of lung transpla

  14. Lifetime costs of lung transplantation : Estimation of incremental costs

    NARCIS (Netherlands)

    VanEnckevort, PJ; Koopmanschap, MA; Tenvergert, EM; VanderBij, W; Rutten, FFH

    1997-01-01

    Despite an expanding number of centres which provide lung transplantation, information about the incremental costs of lung transplantation is scarce. From 1991 until 1995, in The Netherlands a technology assessment was performed which provided information about the incremental costs of lung transpla

  15. Modelling lifetime data with multivariate Tweedie distribution

    Science.gov (United States)

    Nor, Siti Rohani Mohd; Yusof, Fadhilah; Bahar, Arifah

    2017-05-01

    This study aims to measure the dependence between individual lifetimes by applying multivariate Tweedie distribution to the lifetime data. Dependence between lifetimes incorporated in the mortality model is a new form of idea that gives significant impact on the risk of the annuity portfolio which is actually against the idea of standard actuarial methods that assumes independent between lifetimes. Hence, this paper applies Tweedie family distribution to the portfolio of lifetimes to induce the dependence between lives. Tweedie distribution is chosen since it contains symmetric and non-symmetric, as well as light-tailed and heavy-tailed distributions. Parameter estimation is modified in order to fit the Tweedie distribution to the data. This procedure is developed by using method of moments. In addition, the comparison stage is made to check for the adequacy between the observed mortality and expected mortality. Finally, the importance of including systematic mortality risk in the model is justified by the Pearson's chi-squared test.

  16. Cost-effectiveness of newborn circumcision in reducing lifetime HIV risk among U.S. males.

    Directory of Open Access Journals (Sweden)

    Stephanie L Sansom

    Full Text Available BACKGROUND: HIV incidence was substantially lower among circumcised versus uncircumcised heterosexual African men in three clinical trials. Based on those findings, we modeled the potential effect of newborn male circumcision on a U.S. male's lifetime risk of HIV, including associated costs and quality-adjusted life-years saved. METHODOLOGY/PRINCIPAL FINDINGS: Given published estimates of U.S. males' lifetime HIV risk, we calculated the fraction of lifetime risk attributable to heterosexual behavior from 2005-2006 HIV surveillance data. We assumed 60% efficacy of circumcision in reducing heterosexually-acquired HIV over a lifetime, and varied efficacy in sensitivity analyses. We calculated differences in lifetime HIV risk, expected HIV treatment costs and quality-adjusted life years (QALYs among circumcised versus uncircumcised males. The main outcome measure was cost per HIV-related QALY saved. Circumcision reduced the lifetime HIV risk among all males by 15.7% in the base case analysis, ranging from 7.9% for white males to 20.9% for black males. Newborn circumcision was a cost-saving HIV prevention intervention for all, black and Hispanic males. The net cost of newborn circumcision per QALY saved was $87,792 for white males. Results were most sensitive to the discount rate, and circumcision efficacy and cost. CONCLUSIONS/SIGNIFICANCE: Newborn circumcision resulted in lower expected HIV-related treatment costs and a slight increase in QALYs. It reduced the 1.87% lifetime risk of HIV among all males by about 16%. The effect varied substantially by race and ethnicity. Racial and ethnic groups who could benefit the most from circumcision may have least access to it due to insurance coverage and state Medicaid policies, and these financial barriers should be addressed. More data on the long-term protective effect of circumcision on heterosexual males as well as on its efficacy in preventing HIV among MSM would be useful.

  17. Statistical Models and Methods for Lifetime Data

    CERN Document Server

    Lawless, Jerald F

    2011-01-01

    Praise for the First Edition"An indispensable addition to any serious collection on lifetime data analysis and . . . a valuable contribution to the statistical literature. Highly recommended . . ."-Choice"This is an important book, which will appeal to statisticians working on survival analysis problems."-Biometrics"A thorough, unified treatment of statistical models and methods used in the analysis of lifetime data . . . this is a highly competent and agreeable statistical textbook."-Statistics in MedicineThe statistical analysis of lifetime or response time data is a key tool in engineering,

  18. Toward a new spacecraft optimal design lifetime? Impact of marginal cost of durability and reduced launch price

    Science.gov (United States)

    Snelgrove, Kailah B.; Saleh, Joseph Homer

    2016-10-01

    The average design lifetime of satellites continues to increase, in part due to the expectation that the satellite cost per operational day decreases monotonically with increased design lifetime. In this work, we challenge this expectation by revisiting the durability choice problem for spacecraft in the face of reduced launch price and under various cost of durability models. We first provide a brief overview of the economic thought on durability and highlight its limitations as they pertain to our problem (e.g., the assumption of zero marginal cost of durability). We then investigate the merging influence of spacecraft cost of durability and launch price, and we identify conditions that give rise cost-optimal design lifetimes that are shorter than the longest lifetime technically achievable. For example, we find that high costs of durability favor short design lifetimes, and that under these conditions the optimal choice is relatively robust to reduction in launch prices. By contrast, lower costs of durability favor longer design lifetimes, and the optimal choice is highly sensitive to reduction in launch price. In both cases, reduction in launch prices translates into reduction of the optimal design lifetime. Our results identify a number of situations for which satellite operators would be better served by spacecraft with shorter design lifetimes. Beyond cost issues and repeat purchases, other implications of long design lifetime include the increased risk of technological slowdown given the lower frequency of purchases and technology refresh, and the increased risk for satellite operators that the spacecraft will be technologically obsolete before the end of its life (with the corollary of loss of value and competitive advantage). We conclude with the recommendation that, should pressure to extend spacecraft design lifetime continue, satellite manufacturers should explore opportunities to lease their spacecraft to operators, or to take a stake in the ownership

  19. Lifetime-Aware Battery Allocation for Wireless Sensor Network under Cost Constraints

    Science.gov (United States)

    Liu, Yongpan; Wang, Yiqun; Long, Hengyu; Yang, Huazhong

    Battery-powered wireless sensor networks are prone to premature failures because some nodes deplete their batteries more rapidly than others due to workload variations, the many-to-one traffic pattern, and heterogeneous hardware. Most previous sensor network lifetime enhancement techniques focused on balancing the power distribution, assuming the usage of the identical battery. This paper proposes a novel fine-grained cost-constrained lifetime-aware battery allocation solution for sensor networks with arbitrary topologies and heterogeneous power distributions. Based on an energy-cost battery pack model and optimal node partitioning algorithm, a rapid battery pack selection heuristic is developed and its deviation from optimality is quantified. Furthermore, we investigate the impacts of the power variations on the lifetime extension by battery allocation. We prove a theorem to show that power variations of nodes are more likely to reduce the lifetime than to increase it. Experimental results indicate that the proposed technique achieves network lifetime improvements ranging from 4-13× over the uniform battery allocation, with no more than 10 battery pack levels and 2-5 orders of magnitudes speedup compared with a standard integer nonlinear program solver (INLP).

  20. Lifetime medical costs of obesity: prevention no cure for increasing health expenditure.

    Directory of Open Access Journals (Sweden)

    Pieter H M van Baal

    2008-02-01

    Full Text Available BACKGROUND: Obesity is a major cause of morbidity and mortality and is associated with high medical expenditures. It has been suggested that obesity prevention could result in cost savings. The objective of this study was to estimate the annual and lifetime medical costs attributable to obesity, to compare those to similar costs attributable to smoking, and to discuss the implications for prevention. METHODS AND FINDINGS: With a simulation model, lifetime health-care costs were estimated for a cohort of obese people aged 20 y at baseline. To assess the impact of obesity, comparisons were made with similar cohorts of smokers and "healthy-living" persons (defined as nonsmokers with a body mass index between 18.5 and 25. Except for relative risk values, all input parameters of the simulation model were based on data from The Netherlands. In sensitivity analyses the effects of epidemiologic parameters and cost definitions were assessed. Until age 56 y, annual health expenditure was highest for obese people. At older ages, smokers incurred higher costs. Because of differences in life expectancy, however, lifetime health expenditure was highest among healthy-living people and lowest for smokers. Obese individuals held an intermediate position. Alternative values of epidemiologic parameters and cost definitions did not alter these conclusions. CONCLUSIONS: Although effective obesity prevention leads to a decrease in costs of obesity-related diseases, this decrease is offset by cost increases due to diseases unrelated to obesity in life-years gained. Obesity prevention may be an important and cost-effective way of improving public health, but it is not a cure for increasing health expenditures.

  1. Charmed particle lifetimes. [Review, six quark model

    Energy Technology Data Exchange (ETDEWEB)

    Rosner, J.L.

    1979-01-01

    Conventional estimates are reviewed for charmed particle lifetimes. Free-quark models give values of (a few) x 10/sup -13/ sec to (a few) x 10/sup -12/ sec. The shorter of these values also follows from an extrapolation based on D ..-->.. Ke/sup nu/. Possible differences among the lifetimes and production rates of D/sup 0/, D/sup +/, F/sup +/, C/sub 0//sup +/, the heavy lepton tau, and the fifth quark b are discussed. Extreme values of mixing angles in a six-quark model could extend charmed particle lifetimes by a factor of at most three from the above estimates, while shorter lifetimes than those predicted could occur for some species like D/sup 0/ or F/sup +/ if their nonleptonic decays were enhanced. The predictions are discussed in the light of some current experimental results, and it is estimated that sigma(pp ..-->.. charm) approx. = 10 ..mu..b at 400 GeV/c. 95 references.

  2. Optimizing design of converters using power cycling lifetime models

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Ørndrup; Munk-Nielsen, Stig

    2015-01-01

    Converter power cycling lifetime depends heavily on converter operation point. A lifetime model of a single power module switched mode power supply with wide input voltage range is shown. A lifetime model is created using a power loss model, a thermal model and a model for power cycling capability...... with a given mission profile. A method to improve the expected lifetime of the converter is presented, taking into account switching frequency, input voltage and transformer turns ratio....

  3. The total lifetime health cost savings of smoking cessation to society

    DEFF Research Database (Denmark)

    Rasmussen, Gitte Susanne; Prescott, Eva; Sørensen, Thorkild I A;

    2005-01-01

    Smoking cessation has major immediate and long-term health benefits. However, ex-smokers' total lifetime health costs and continuing smokers' costs remain uncompared, and hence the economic savings of smoking cessation to society have not been determined....

  4. Predictive Models of Li-ion Battery Lifetime (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G.; Shi, Y.; Pesaran, A.

    2014-09-01

    Predictive models of Li-ion battery reliability must consider a multiplicity of electrochemical, thermal and mechanical degradation modes experienced by batteries in application environments. Complicating matters, Li-ion batteries can experience several path dependent degradation trajectories dependent on storage and cycling history of the application environment. Rates of degradation are controlled by factors such as temperature history, electrochemical operating window, and charge/discharge rate. Lacking accurate models and tests, lifetime uncertainty must be absorbed by overdesign and warranty costs. Degradation models are needed that predict lifetime more accurately and with less test data. Models should also provide engineering feedback for next generation battery designs. This presentation reviews both multi-dimensional physical models and simpler, lumped surrogate models of battery electrochemical and mechanical degradation. Models are compared with cell- and pack-level aging data from commercial Li-ion chemistries. The analysis elucidates the relative importance of electrochemical and mechanical stress-induced degradation mechanisms in real-world operating environments. Opportunities for extending the lifetime of commercial battery systems are explored.

  5. Lifetime

    Institute of Scientific and Technical Information of China (English)

    姚祎

    2004-01-01

    @@ 继ESPN刊出同名杂志之后,2003年赫斯特公司(Hearst Corp.)和迪斯尼(Walt Disney Co.)的合作促成了一本新杂志的诞生:(Lifetime),其目标读者是成百万收看同名有线电视网节目的妇女们.

  6. Advanced Models and Controls for Prediction and Extension of Battery Lifetime (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G.; Pesaran, A.

    2014-02-01

    Predictive models of capacity and power fade must consider a multiplicity of degradation modes experienced by Li-ion batteries in the automotive environment. Lacking accurate models and tests, lifetime uncertainty must presently be absorbed by overdesign and excess warranty costs. To reduce these costs and extend life, degradation models are under development that predict lifetime more accurately and with less test data. The lifetime models provide engineering feedback for cell, pack and system designs and are being incorporated into real-time control strategies.

  7. Remaining Useful Lifetime (RUL - Probabilistic Predictive Model

    Directory of Open Access Journals (Sweden)

    Ephraim Suhir

    2011-01-01

    Full Text Available Reliability evaluations and assurances cannot be delayed until the device (system is fabricated and put into operation. Reliability of an electronic product should be conceived at the early stages of its design; implemented during manufacturing; evaluated (considering customer requirements and the existing specifications, by electrical, optical and mechanical measurements and testing; checked (screened during manufacturing (fabrication; and, if necessary and appropriate, maintained in the field during the product’s operation Simple and physically meaningful probabilistic predictive model is suggested for the evaluation of the remaining useful lifetime (RUL of an electronic device (system after an appreciable deviation from its normal operation conditions has been detected, and the increase in the failure rate and the change in the configuration of the wear-out portion of the bathtub has been assessed. The general concepts are illustrated by numerical examples. The model can be employed, along with other PHM forecasting and interfering tools and means, to evaluate and to maintain the high level of the reliability (probability of non-failure of a device (system at the operation stage of its lifetime.

  8. Lifetime Cost-Effectiveness of Calcineurin Inhibitor Withdrawal After De Novo Renal Transplantation

    Science.gov (United States)

    Earnshaw, Stephanie R.; Graham, Christopher N.; Irish, William D.; Sato, Reiko; Schnitzler, Mark A.

    2008-01-01

    After renal transplantation, immunosuppressive regimens associated with high short-term survival rates are not necessarily associated with high long-term survival rates, suggesting that regimens may need to be optimized over time. Calcineurin inhibitor (CNI) withdrawal from a sirolimus-based immunosuppressive regimen may maximize the likelihood of long-term graft and patient survival by minimizing CNI-associated nephrotoxicity. In this study, a lifetime Markov model was created to compare the cost-effectiveness of a sirolimus-based CNI withdrawl regimen (sirolimus plus steroids) with other common CNI-containing regimens in adult de novo renal transplantation patients. Long-term graft survival was estimated by renal function and data from published studies and the US transplant registry, including short- and long-term outcomes, utility weights, and health-state costs were incorporated. Drug costs were based on average daily consumption and wholesale acquisition costs. The model suggests that treatment with sirolimus plus steroids is more efficacious and less costly than regimens consisting of a CNI, mycophenolate mofetil, and steroids; therefore, CNI withdrawal not only shows potential for long-term clinical benefits but also is expected to be cost-saving over a patient's life compared with the most commonly prescribed CNI-containing regimens. PMID:18562571

  9. Distribution Network Design for Fixed Lifetime Perishable Products: A Model and Solution Approach

    Directory of Open Access Journals (Sweden)

    Z. Firoozi

    2013-01-01

    Full Text Available Nowadays, many distribution networks deal with the distribution and storage of perishable products. However, distribution network design models are largely based on assumptions that do not consider time limitations for the storage of products within the network. This study develops a model for the design of a distribution network that considers the short lifetime of perishable products. The model simultaneously determines the network configuration and inventory control decisions of the network. Moreover, as the lifetime is strictly dependent on the storage conditions, the model develops a trade-off between enhancing storage conditions (higher inventory cost to obtain a longer lifetime and selecting those storage conditions that lead to shorter lifetimes (less inventory cost. To solve the model, an efficient Lagrangian relaxation heuristic algorithm is developed. The model and algorithm are validated by sensitivity analysis on some key parameters. Results show that the algorithm finds optimal or near optimal solutions even for large-size cases.

  10. A Real Options Approach to Quantity and Cost Optimization for Lifetime and Bridge Buys of Parts

    Science.gov (United States)

    2015-04-30

    greater than zero penalty cost avoided , but LTB costs will have to be paid. The cost avoidances in Equation 1 are uncertain due to uncertainties in...buys and to determine the optimum part quantity for a lifetime or bridge buy. The approach accommodates uncertainties in demand, holding costs, and end... uncertainties in demand, holding costs, and end of support dates. Introduction Background A significant problem facing many complex systems is

  11. Estimating Lifetime Costs of Social Care: A Bayesian Approach Using Linked Administrative Datasets from Three Geographical Areas.

    Science.gov (United States)

    Steventon, Adam; Roberts, Adam

    2015-12-01

    We estimated lifetime costs of publicly funded social care, covering services such as residential and nursing care homes, domiciliary care and meals. Like previous studies, we constructed microsimulation models. However, our transition probabilities were estimated from longitudinal, linked administrative health and social care datasets, rather than from survey data. Administrative data were obtained from three geographical areas of England, and we estimated transition probabilities in each of these sites flexibly using Bayesian methods. This allowed us to quantify regional variation as well as the impact of structural and parameter uncertainty regarding the transition probabilities. Expected lifetime costs at age 65 were £20,200-27,000 for men and £38,700-49,000 for women, depending on which of the three areas was used to calibrate the model. Thus, patterns of social care spending differed markedly between areas, with mean costs varying by almost £10,000 (25%) across the lifetime for people of the same age and gender. Allowing for structural and parameter uncertainty had little impact on expected lifetime costs, but slightly increased the risk of very high costs, which will have implications for insurance products for social care through increasing requirements for capital reserves.

  12. Lifetime health effects and costs of diabetes treatment

    NARCIS (Netherlands)

    L.W. Niessen (Louis Wilhelmus); R. Dijkstra; R.C.W. Hutubessy (Raymond); G.E.H.M. Rutten (Guy); A.F. Casparie (Anton)

    2003-01-01

    textabstractBACKGROUND: This article presents cost-effectiveness analyses of the major diabetes interventions as formulated in the revised Dutch guidelines for diabetes type 2 patients in primary and secondary care. The analyses consider two types of care: diabetes control and the

  13. Lifetime medical costs of obesity : Prevention no cure for increasing health expenditure

    NARCIS (Netherlands)

    van Baal, Pieter H. M.; Polder, Johan J.; de Wit, G. Ardine; Hoogenveen, Rudolf T.; Feenstra, Talitha L.; Boshuizen, Hendriek C.; Engelfriet, Peter M.; Brouwer, Werner B. F.

    2008-01-01

    Background Obesity is a major cause of morbidity and mortality and is associated with high medical expenditures. It has been suggested that obesity prevention could result in cost savings. The objective of this study was to estimate the annual and lifetime medical costs attributable to obesity, to c

  14. Lifetime Modeling of Thermal Barrier Coatings

    NARCIS (Netherlands)

    Hille, T.S.

    2009-01-01

    Thermal barrier coatings (TBCs) are applied in gas turbines to enhance their thermal efficiency by isolating the metallic components from the aggressive hot gas. TBC lifetime is limited by damage processes originating at internal interfaces, which may ultimately lead to delamination and spallation.

  15. State-Level Lifetime Medical and Work-Loss Costs of Fatal Injuries - United States, 2014.

    Science.gov (United States)

    Luo, Feijun; Florence, Curtis

    2017-01-13

    Injury-associated deaths have substantial economic consequences in the United States. The total estimated lifetime medical and work-loss costs associated with fatal injuries in 2013 were $214 billion (1). In 2014, unintentional injury, suicide, and homicide (the fourth, tenth, and seventeenth leading causes of death, respectively) accounted for 194,635 deaths in the United States (2). In 2014, a total of 199,756 fatal injuries occurred in the United States, and the associated lifetime medical and work-loss costs were $227 billion (3). This report examines the state-level economic burdens of fatal injuries by extending a previous national-level study (1). Numbers and rates of fatal injuries, lifetime costs, and lifetime costs per capita were calculated for each of the 50 states and the District of Columbia (DC) and for four injury intent categories (all intents, unintentional, suicide, and homicide). During 2014, injury mortality rates and economic burdens varied widely among the states and DC. Among fatal injuries of all intents, the mortality rate and lifetime costs per capita ranged from 101.9 per 100,000 and $1,233, respectively (New Mexico) to 40.2 per 100,000 and $491 (New York). States can engage more effectively and efficiently in injury prevention if they are aware of the economic burden of injuries, identify areas for immediate improvement, and devote necessary resources to those areas.

  16. Cost and Performance Model for Photovoltaic Systems

    Science.gov (United States)

    Borden, C. S.; Smith, J. H.; Davisson, M. C.; Reiter, L. J.

    1986-01-01

    Lifetime cost and performance (LCP) model assists in assessment of design options for photovoltaic systems. LCP is simulation of performance, cost, and revenue streams associated with photovoltaic power systems connected to electric-utility grid. LCP provides user with substantial flexibility in specifying technical and economic environment of application.

  17. Lifetime of {sup 44}Ti as probe for supernova models

    Energy Technology Data Exchange (ETDEWEB)

    Goerres, J.; Meissner, J.; Schatz, H.; Stech, E.; Tischhauser, P.; Wiescher, M. [Univ. of Notre Dame, Notre Dame, IN (United States); Bazin, D.; Harkewicz, R.; Hellstroem, M.; Sherrill, B.; Steiner, M. [Michigan State Univ., East Lansing, MI (United States); Boyd, R.N. [Ohio State Univ., Columbus, OH (United States); Buchmann, L. [TRIUMF, Vancouver, BC (Canada); Hartmann, D.H. [Clemson Univ., Clemson, SC (United States); Hinnefeld, J.D. [Indiana Univ. South Bend, South Bend, IN (United States)

    1998-06-01

    The recent observation of {sup 44}Ti radioactivity in the supernova remnant Cassiopeia A with the Compton Gamma Ray Observatory allows the determination of the absolute amount of {sup 44}Ti. This provides a test for current supernova models. The main uncertainty is the lifetime of {sup 44}Ti. We report a new measurement of the lifetime of {sup 44}Ti applying a novel technique. A mixed radioactive beam containing {sup 44}Ti as well as {sup 22}Na was implanted and the resulting {gamma}-activity was measured. This allowed the determination of the lifetime of {sup 44}Ti relative to the lifetime of {sup 22}Na, {tau} = (87.0 {+-} 1.9) y. With this lifetime, the {sup 44}Ti abundance agrees with theoretical predictions within the remaining observational uncertainties. (orig.)

  18. Lifetime-Aware Cloud Data Centers: Models and Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Luca Chiaraviglio

    2016-06-01

    Full Text Available We present a model to evaluate the server lifetime in cloud data centers (DCs. In particular, when the server power level is decreased, the failure rate tends to be reduced as a consequence of the limited number of components powered on. However, the variation between the different power states triggers a failure rate increase. We therefore consider these two effects in a server lifetime model, subject to an energy-aware management policy. We then evaluate our model in a realistic case study. Our results show that the impact on the server lifetime is far from negligible. As a consequence, we argue that a lifetime-aware approach should be pursued to decide how and when to apply a power state change to a server.

  19. Modeling and optimization of membrane lifetime in dead-end ultra filtration

    NARCIS (Netherlands)

    Zondervan, Edwin; Roffel, Brian

    2008-01-01

    In this paper, a membrane lifetime model is developed and experimentally validated. The lifetime model is based on the Weibull probability density function. The lifetime model can be used to determine an unambiguous characteristic membrane lifetime. Experimental results showed that membrane lifetime

  20. Predictive Models of Li-ion Battery Lifetime

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kandler; Wood, Eric; Santhanagopalan, Shriram; Kim, Gi-heon; Shi, Ying; Pesaran, Ahmad

    2015-06-15

    It remains an open question how best to predict real-world battery lifetime based on accelerated calendar and cycle aging data from the laboratory. Multiple degradation mechanisms due to (electro)chemical, thermal, and mechanical coupled phenomena influence Li-ion battery lifetime, each with different dependence on time, cycling and thermal environment. The standardization of life predictive models would benefit the industry by reducing test time and streamlining development of system controls.

  1. Lifetime models of female labor supply, wage rates, and fertility.

    Science.gov (United States)

    Carliner, G; Robinson, C; Tomes, N

    1984-01-01

    A simple 1 period lifetime model is specified in which schooling is part of the lifetime period. This implies that an adding-up constraint is imposed on the uses of time in the lifetime including schooling, which may induce a negative correlation between years of schooling and years in the market, while producing a positive correlation between years of schooling and the fraction of the postschool lifetime spent in the market. The model is used to interpret empirical analyses based on alternative measures of lifetime labor supply and on alternative specifications of which variables may be treated as exogenous. In the empirical analysis the retrospective and longitudinal aspects of the newly available National Longitudinal Survey of Women is used to construct a measure of the fraction of the lifetime supplied to the market and measures of the lifetime wage rates of both the husband and the wife. The empirical results take the lifetime model of labor supply seriously in that the empirical measures of labor supply and wage rates bear a much closer resemblance to the theoretical concepts than measures typically employed in the literature. The estimates indicate that the "plausible assumptions" required for the true coefficient on fertility in a labor supply equation to be zero are fulfilled. These estimates are compared with those obtained using current measures as proxies for lifetime variables. Based on these estimates, an explanation is offered for the apparent contradiction between the findings of studies using a simultaneous equations approach that report no effect of fertility on female labor supply and the strong depressing effect of children on (current) labor supply obtained from research that treats children as exogenous. Current female hours appear more responsive to husbands' current earnings and female education than is the case with the lifetime variables. There are marked differences in the effects of race. The lifetime hours of white women are only some

  2. Cost per QALY (quality-adjusted life year and lifetime cost of prolonged mechanical ventilation in Taiwan.

    Directory of Open Access Journals (Sweden)

    Mei-Chuan Hung

    Full Text Available INTRODUCTION: Patients who require prolonged mechanical ventilation (PMV are increasing and producing financial burdens worldwide. This study determines the cost per QALY (quality-adjusted life year, out-of-pocket expenses, and lifetime costs for PMV patients stratified by underlying diseases and cognition levels. METHODS: A nationwide sample of 50,481 patients with continual mechanical ventilation for more than 21 days was collected during 1997-2007. After stratifying the patients according to specific diagnoses, a latent class analysis (LCA was performed to categorise PMV patients with multiple co-morbidities into several homogeneous groups. The survival functions were estimated for individual groups using the Kaplan-Meier method and extrapolated to 300 months through a semi-parametric method. The survival functions were adjusted using an EQ-5D utility value derived from a convenience sample of 142 PMV patients to estimate quality-adjusted life expectancies (QALE. Another convenience sample of 165 patients was used to estimate the out-of-pocket expenses. The lifetime expenditures paid by the single-payer National Health Insurance (NHI system and patients' families were estimated by multiplying average monthly expenditures by the survival probabilities and summing the values over lifetime. RESULTS: PMV therapy costs more than 100,000 U.S. dollars (USD per QALY for all patients with poor cognition. For patients with partial cognition, PMV therapy costs less than 56,000 USD per QALY for those with liver cirrhosis, intracranial or spinal cord injuries, and 57,000-69,000 USD for patients with multiple co-morbidities under age of 65. The average lifetime cost of PMV was usually below 56,000 USD. The out-of-pocket expenses were often more than one-third of the total cost of treatment. CONCLUSIONS: PMV treatment for patients with poor cognition would cost more than 5 times Taiwan's GDP (gross domestic products, or less cost-effective. The out

  3. Lifetime injury prevention: The sport profile model*

    African Journals Online (AJOL)

    2012-01-04

    Jan 4, 2012 ... develop models of understanding of injury risk at different life ... University of Brighton, Sussex Centre for Sport and Exercise ... of knee and hip osteoarthritis in former professional soccer players is ... equally to all situations for that sport. .... prevention and better treatment of injuries that limit physical activity.

  4. Modeling churn using customer lifetime value

    OpenAIRE

    Glady, Nicolas; Baesens, Bart; Croux, Christophe

    2009-01-01

    The definition and modeling of customer loyalty have been central issues in customer relationship management since many years. Recent papers propose solutions to detect customers that are becoming less loyal, also called churners. The churner status is then defined as a function of the volume of commercial transactions. In the context of a Belgian retail financial service company, our first contribution is to redefine the notion of customer loyalty by considering it from a customer-centric vi...

  5. Modeling customer loyalty using customer lifetime value.

    OpenAIRE

    Glady, N.; Baesens, Bart; Croux, Christophe

    2006-01-01

    The definition and modeling of customer loyalty have been central issues in customer relationship management since many years. Recent papers propose solutions to detect customers that are becoming less loyal, also called churners. The churner status is then defined as a function of the volume of commercial transactions. In the context of a Belgian retail financial service company, our first contribution will be to redefine the notion of customer's loyalty by considering it from a customer-cen...

  6. Design of Boiler Welding for Improvement of Lifetime and Cost Control

    OpenAIRE

    Atcharawadi Thong-On; Chatdanai Boonruang

    2016-01-01

    Fe-2.25Cr-1Mo a widely used material for headers and steam tubes of boilers. Welding of steam tube to header is required for production of boiler. Heat affected zone of the weld can have poor mechanical properties and poor corrosion behavior leading to weld failure. The cost of material used for steam tube and header of boiler should be controlled. This study propose a new materials design for boiler welding to improve the lifetime and cost control, using tungsten inert gas (TIG) welding of F...

  7. Mathematical Model of Lifetime Duration at Insulation of Electrical Machines

    Directory of Open Access Journals (Sweden)

    Mihaela Răduca

    2009-10-01

    Full Text Available Abstract. This paper present a mathematical model of lifetime duration at hydro generator stator winding insulation when at hydro generator can be appear the damage regimes. The estimation to make by take of the programming and non-programming revisions, through the introduction and correlation of the new defined notions.

  8. Remaining lifetime modeling using State-of-Health estimation

    Science.gov (United States)

    Beganovic, Nejra; Söffker, Dirk

    2017-08-01

    Technical systems and system's components undergo gradual degradation over time. Continuous degradation occurred in system is reflected in decreased system's reliability and unavoidably lead to a system failure. Therefore, continuous evaluation of State-of-Health (SoH) is inevitable to provide at least predefined lifetime of the system defined by manufacturer, or even better, to extend the lifetime given by manufacturer. However, precondition for lifetime extension is accurate estimation of SoH as well as the estimation and prediction of Remaining Useful Lifetime (RUL). For this purpose, lifetime models describing the relation between system/component degradation and consumed lifetime have to be established. In this contribution modeling and selection of suitable lifetime models from database based on current SoH conditions are discussed. Main contribution of this paper is the development of new modeling strategies capable to describe complex relations between measurable system variables, related system degradation, and RUL. Two approaches with accompanying advantages and disadvantages are introduced and compared. Both approaches are capable to model stochastic aging processes of a system by simultaneous adaption of RUL models to current SoH. The first approach requires a priori knowledge about aging processes in the system and accurate estimation of SoH. An estimation of SoH here is conditioned by tracking actual accumulated damage into the system, so that particular model parameters are defined according to a priori known assumptions about system's aging. Prediction accuracy in this case is highly dependent on accurate estimation of SoH but includes high number of degrees of freedom. The second approach in this contribution does not require a priori knowledge about system's aging as particular model parameters are defined in accordance to multi-objective optimization procedure. Prediction accuracy of this model does not highly depend on estimated SoH. This model

  9. Design of Boiler Welding for Improvement of Lifetime and Cost Control

    Directory of Open Access Journals (Sweden)

    Atcharawadi Thong-On

    2016-11-01

    Full Text Available Fe-2.25Cr-1Mo a widely used material for headers and steam tubes of boilers. Welding of steam tube to header is required for production of boiler. Heat affected zone of the weld can have poor mechanical properties and poor corrosion behavior leading to weld failure. The cost of material used for steam tube and header of boiler should be controlled. This study propose a new materials design for boiler welding to improve the lifetime and cost control, using tungsten inert gas (TIG welding of Fe-2.25Cr-1Mo tube to carbon steel pipe with chromium-containing filler. The cost of production could be reduced by the use of low cost material such as carbon steel pipe for boiler header. The effect of chromium content on corrosion behavior of the weld was greater than that of the microstructure. The lifetime of the welded boiler can be increased by improvement of mechanical properties and corrosion behavior of the heat affected zone.

  10. Cost model for biobanks.

    Science.gov (United States)

    Gonzalez-Sanchez, M Beatriz; Lopez-Valeiras, Ernesto; Morente, Manuel M; Fernández Lago, Orlando

    2013-10-01

    Current economic conditions and budget constraints in publicly funded biomedical research have brought about a renewed interest in analyzing the cost and economic viability of research infrastructures. However, there are no proposals for specific cost accounting models for these types of organizations in the international scientific literature. The aim of this paper is to present the basis of a cost analysis model useful for any biobank regardless of the human biological samples that it stores for biomedical research. The development of a unique cost model for biobanks can be a complicated task due to the diversity of the biological samples they store. Different types of samples (DNA, tumor tissues, blood, serum, etc.) require different production processes. Nonetheless, the common basic steps of the production process can be identified. Thus, the costs incurred in each step can be analyzed in detail to provide cost information. Six stages and four cost objects were obtained by taking the production processes of biobanks belonging to the Spanish National Biobank Network as a starting point. Templates and examples are provided to help managers to identify and classify the costs involved in their own biobanks to implement the model. The application of this methodology will provide accurate information on cost objects, along with useful information to give an economic value to the stored samples, to analyze the efficiency of the production process and to evaluate the viability of some sample collections.

  11. Comparison of Parameter Estimation Methods for Transformer Weibull Lifetime Modelling

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dan; LI Chengrong; WANG Zhongdong

    2013-01-01

    Two-parameter Weibull distribution is the most widely adopted lifetime model for power transformers.An appropriate parameter estimation method is essential to guarantee the accuracy of a derived Weibull lifetime model.Six popular parameter estimation methods (i.e.the maximum likelihood estimation method,two median rank regression methods including the one regressing X on Y and the other one regressing Y on X,the Kaplan-Meier method,the method based on cumulative hazard plot,and the Li's method) are reviewed and compared in order to find the optimal one that suits transformer's Weibull lifetime modelling.The comparison took several different scenarios into consideration:10 000 sets of lifetime data,each of which had a sampling size of 40 ~ 1 000 and a censoring rate of 90%,were obtained by Monte-Carlo simulations for each scienario.Scale and shape parameters of Weibull distribution estimated by the six methods,as well as their mean value,median value and 90% confidence band are obtained.The cross comparison of these results reveals that,among the six methods,the maximum likelihood method is the best one,since it could provide the most accurate Weibull parameters,i.e.parameters having the smallest bias in both mean and median values,as well as the shortest length of the 90% confidence band.The maximum likelihood method is therefore recommended to be used over the other methods in transformer Weibull lifetime modelling.

  12. Sunspot and starspot lifetimes in a turbulent erosion model

    CERN Document Server

    Litvinenko, Yuri E

    2016-01-01

    Quantitative models of sunspot and starspot decay predict the timescale of magnetic diffusion and may yield important constraints in stellar dynamo models. Motivated by recent measurements of starspot lifetimes, we investigate the disintegration of a magnetic flux tube by nonlinear diffusion. Previous theoretical studies are extended by considering two physically motivated functional forms for the nonlinear diffusion coefficient $D$: an inverse power-law dependence $D \\propto B^{-\

  13. The Sprint to Lifetime Sports

    Science.gov (United States)

    Ernst, Leonard

    1973-01-01

    Describes the trend in high school physical education programs toward lifetime sports, defined by the author as physical activities that will serve the interests of students for a lifetime. Included are a special report on program costs and a model of a performance-based lifetime sports program. (Author/DN)

  14. Dynamical modeling and lifetime analysis of geostationary transfer orbits

    Science.gov (United States)

    Wang, Yue; Gurfil, Pini

    2016-11-01

    The dynamics and lifetime reduction of geostationary transfer orbits (GTOs) are of great importance to space debris mitigation. The orbital dynamics, subjected to a complex interplay of multiple perturbations, are complicated and sensitive to the initial conditions and model parameters. In this paper, a simple but effective non-singular orbital dynamics model in terms of Milankovitch elements is derived. The orbital dynamics, which include the Earth oblateness, luni-solar perturbations, and atmospheric drag, are averaged over the orbital motion of the GTO object, or, as needed, also over the orbital motions of the Moon and Sun, to eliminate the short-period terms. After the averaging process, the effect of the atmospheric drag assumes a simple analytical form. The averaged orbital model is verified through a numerical simulation compared with commercial orbit propagators. GTO lifetime reduction by using the luni-solar perturbations is studied. It is shown that the long-period luni-solar perturbation is induced by the precession of the GTO orbital plane and apsidal line, whereas the short-period perturbation is induced by the periodic luni-solar orbital motions. The long- and short-period perturbations are isolated and studied separately, and their global distribution with respect to the orbital geometry is given. The desired initial orbital geometry with a short orbital lifetime is found and verified by a numerical simulation.

  15. Lifetime Cost-Effectiveness of Calcineurin Inhibitor Withdrawal After De Novo Renal Transplantation

    OpenAIRE

    Earnshaw, Stephanie R; Graham, Christopher N.; Irish, William D.; Sato, Reiko; Mark A. Schnitzler

    2008-01-01

    After renal transplantation, immunosuppressive regimens associated with high short-term survival rates are not necessarily associated with high long-term survival rates, suggesting that regimens may need to be optimized over time. Calcineurin inhibitor (CNI) withdrawal from a sirolimus-based immunosuppressive regimen may maximize the likelihood of long-term graft and patient survival by minimizing CNI-associated nephrotoxicity. In this study, a lifetime Markov model was created to compare the...

  16. A simulation model for the lifetime of wireless sensor networks

    CERN Document Server

    Elleithy, Abdelrahman

    2012-01-01

    In this paper we present a model for the lifetime of wireless sensor networks. The model takes into consideration several parameters such as the total number of sensors, network size, percentage of sink nodes, location of sensors, the mobility of sensors, and power consumption. A definition of the life time of the network based on three different criteria is introduced; percentage of available power to total power, percentage of alive sensors to total sensors, and percentage of alive sink sensors to total sink sensors. A Matlab based simulator is developed for the introduced model. A number of wireless sensor networks scenarios are presented and discussed.

  17. Costs of mating competition limit male lifetime breeding success in polygynous mammals.

    Science.gov (United States)

    Lukas, Dieter; Clutton-Brock, Tim

    2014-07-01

    Although differences in breeding lifespan are an important source of variation in male fitness, the factors affecting the breeding tenure of males have seldom been explored. Here, we use cross-species comparisons to investigate the correlates of breeding lifespan in male mammals. Our results show that male breeding lifespan depends on the extent of polygyny, which reflects the relative intensity of competition for access to females. Males have relatively short breeding tenure in species where individuals have the potential to monopolize mating with multiple females, and longer ones where individuals defend one female at a time. Male breeding tenure is also shorter in species in which females breed frequently than in those where females breed less frequently, suggesting that the costs of guarding females may contribute to limiting tenure length. As a consequence of these relationships, estimates of skew in male breeding success within seasons overestimate skew calculated across the lifetime and, in several polygynous species, variance in lifetime breeding success is not substantially higher in males than in females.

  18. A simple model for skewed species-lifetime distributions

    KAUST Repository

    Murase, Yohsuke

    2010-06-11

    A simple model of a biological community assembly is studied. Communities are assembled by successive migrations and extinctions of species. In the model, species are interacting with each other. The intensity of the interaction between each pair of species is denoted by an interaction coefficient. At each time step, a new species is introduced to the system with randomly assigned interaction coefficients. If the sum of the coefficients, which we call the fitness of a species, is negative, the species goes extinct. The species-lifetime distribution is found to be well characterized by a stretched exponential function with an exponent close to 1/2. This profile agrees not only with more realistic population dynamics models but also with fossil records. We also find that an age-independent and inversely diversity-dependent mortality, which is confirmed in the simulation, is a key mechanism accounting for the distribution. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

  19. Estimating the lifetime economic burden of stroke according to the age of onset in South Korea: a cost of illness study

    Directory of Open Access Journals (Sweden)

    Suh Hae Sun

    2011-08-01

    Full Text Available Abstract Background The recently-observed trend towards younger stroke patients in Korea raises economic concerns, including erosion of the workforce. We compared per-person lifetime costs of stroke according to the age of stroke onset from the Korean societal perspective. Methods A state-transition Markov model consisted of three health states ('post primary stroke event', 'alive post stroke', and 'dead' was developed to simulate the natural history of stroke. The transition probabilities for fatal and non-fatal recurrent stroke by age and gender and for non-stroke causes of death were derived from the national epidemiologic data of the Korean Health Insurance Review and Assessment Services and data from the Danish Monitoring Trends in Cardiovascular Disease study. We used an incidence-based approach to estimate the long-term costs of stroke. The model captured stroke-related costs including costs within the health sector, patients' out-of-pocket costs outside the health sector, and costs resulting from loss of productivity due to morbidity and premature death using a human capital approach. Average insurance-covered costs occurring within the health sector were estimated from the National Health Insurance claims database. Other costs were estimated based on the national epidemiologic data and literature. All costs are presented in 2008 Korean currency values (Korean won = KRW. Results The lifetime costs of stroke were estimated to be: 200.7, 81.9, and 16.4 million Korean won (1,200 KRW is approximately equal to one US dollar for men who suffered a first stroke at age 45, 55 and 65 years, respectively, and 75.7, 39.2, and 19.3 million KRW for women at the same age. While stroke occurring among Koreans aged 45 to 64 years accounted for only 30% of the total disease incidence, this age group incurred 75% of the total national lifetime costs of stroke. Conclusions A higher lifetime burden and increasing incidence of stroke among younger Koreans

  20. LIFETIME PREDICTION FOR MODEL 9975 O-RINGS IN KAMS

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, E.; Skidmore, E.

    2009-11-24

    The Savannah River Site (SRS) is currently storing plutonium materials in the K-Area Materials Storage (KAMS) facility. The materials are packaged per the DOE 3013 Standard and transported and stored in KAMS in Model 9975 shipping packages, which include double containment vessels sealed with dual O-rings made of Parker Seals compound V0835-75 (based on Viton{reg_sign} GLT). The outer O-ring of each containment vessel is credited for leaktight containment per ANSI N14.5. O-ring service life depends on many factors, including the failure criterion, environmental conditions, overall design, fabrication quality and assembly practices. A preliminary life prediction model has been developed for the V0835-75 O-rings in KAMS. The conservative model is based primarily on long-term compression stress relaxation (CSR) experiments and Arrhenius accelerated-aging methodology. For model development purposes, seal lifetime is defined as a 90% loss of measurable sealing force. Thus far, CSR experiments have only reached this target level of degradation at temperatures {ge} 300 F. At lower temperatures, relaxation values are more tolerable. Using time-temperature superposition principles, the conservative model predicts a service life of approximately 20-25 years at a constant seal temperature of 175 F. This represents a maximum payload package at a constant ambient temperature of 104 F, the highest recorded in KAMS to date. This is considered a highly conservative value as such ambient temperatures are only reached on occasion and for short durations. The presence of fiberboard in the package minimizes the impact of such temperature swings, with many hours to several days required for seal temperatures to respond proportionately. At 85 F ambient, a more realistic but still conservative value, bounding seal temperatures are reduced to {approx}158 F, with an estimated seal lifetime of {approx}35-45 years. The actual service life for O-rings in a maximum wattage package likely lies

  1. The predicted lifetime costs and health consequences of calcium and vitamin D supplementation for fracture preventio

    DEFF Research Database (Denmark)

    Hagen, G.; Wisløff, T.; Sønbø Kristiansen, Ivar

    2016-01-01

    Summary: Some studies indicate that calcium supplementation increases cardiovascular risk. We assessed whether such effects could counterbalance the fracture benefits from supplementation. Accounting for cardiovascular outcomes, calcium may cause net harm and would not be cost-effective. Clinicians...... and to evaluate the cost-effectiveness of such supplementation. Methods: We created a probabilistic Markov simulation model that was analysed at the individual patient level. We analysed 65-year-old Norwegian women with a 2.3 % 10-year risk of hip fracture and a 9.3 % risk of any major fracture according......-, and high-risk scenario. Results: Assuming no cardiovascular effects, CaD supplementation produces improved health outcomes resulting in an incremental gain of 0.0223 quality-adjusted life years (QALYs) and increases costs by €322 compared with no treatment (cost-effectiveness ratio €14,453 per QALY gained...

  2. A New Estimation Model of IC Interconnect Lifetime Based on Uniform Defect Distribution Model

    Institute of Scientific and Technical Information of China (English)

    ZHAOTianxu; DUANXuchao; HAOYue; MAPeijun

    2004-01-01

    Defect, which exists throughout IC manufacturing process, is one of the important factors affecting IC interconnection lifetime. In this paper, a new failure model of IC interconnection is proposed based on analysis of the awdlable lifetime estimation models of IC interconnect lifetime. Many factors, such as the sizes of the defect, wire width, wire length and so on, are considered in this new model. The simulation results show that defect has a great influence on IC's interconnect lifetime, and the larger the defect size, the greater the influence. The new model can be used in an IC design to estimate electromigration loss related to the IC missing material defect and to some other factors.

  3. Evaluation of Battery Lifetimes using Inhomogeneous Markov Reward Models

    NARCIS (Netherlands)

    Cloth, L.; Haverkort, Boudewijn R.H.M.; Jongerden, M.R.

    2006-01-01

    The usage of mobile devices like cell phones, navigation systems, or laptop computers, is limited by the lifetime of the included batteries. This lifetimes depends naturally on the rate at which energy is consumed, however, it also depends on the usage pattern of the battery. Continuous drawing of a

  4. Evaluation of Battery Lifetimes using Inhomogeneous Markov Reward Models

    NARCIS (Netherlands)

    Cloth, Lucia; Haverkort, Boudewijn R.; Jongerden, Marijn

    2006-01-01

    The usage of mobile devices like cell phones, navigation systems, or laptop computers, is limited by the lifetime of the included batteries. This lifetimes depends naturally on the rate at which energy is consumed, however, it also depends on the usage pattern of the battery. Continuous drawing of a

  5. Sunspot and Starspot Lifetimes in a Turbulent Erosion Model

    Science.gov (United States)

    Litvinenko, Yuri E.; Wheatland, M. S.

    2017-01-01

    Quantitative models of sunspot and starspot decay predict the timescale of magnetic diffusion and may yield important constraints in stellar dynamo models. Motivated by recent measurements of starspot lifetimes, we investigate the disintegration of a magnetic flux tube by nonlinear diffusion. Previous theoretical studies are extended by considering two physically motivated functional forms for the nonlinear diffusion coefficient D: an inverse power-law dependence D ∝ B‑ν and a step-function dependence of D on the magnetic field magnitude B. Analytical self-similar solutions are presented for the power-law case, including solutions exhibiting “superfast” diffusion. For the step-function case, the heat-balance integral method yields approximate solutions, valid for moderately suppressed diffusion in the spot. The accuracy of the resulting solutions is confirmed numerically, using a method which provides an accurate description of long-time evolution by imposing boundary conditions at infinite distance from the spot. The new models may allow insight into the differences and similarities between sunspots and starspots.

  6. Two-Year and Lifetime Cost-Effectiveness of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Head-and-Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Racquel E. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Sheets, Nathan C. [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States); Wheeler, Stephanie B. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Nutting, Chris [Royal Marsden Hospital, London, United Kindom (United Kingdom); Hall, Emma [Clinical Trials and Statistics Unit, Division of Clinical Studies, Institute of Cancer Research, London (United Kingdom); Chera, Bhishamjit S., E-mail: bchera@med.unc.edu [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States)

    2013-11-15

    Purpose: To assess the cost-effectiveness of intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3D-CRT) in the treatment of head-and neck-cancer (HNC). Methods and Materials: We used a Markov model to simulate radiation therapy-induced xerostomia and dysphagia in a hypothetical cohort of 65-year-old HNC patients. Model input parameters were derived from PARSPORT (CRUK/03/005) patient-level trial data and quality-of-life and Medicare cost data from published literature. We calculated average incremental cost-effectiveness ratios (ICERs) from the US health care perspective as cost per quality-adjusted life-year (QALY) gained and compared our ICERs with current cost-effectiveness standards whereby treatment comparators less than $50,000 per QALY gained are considered cost-effective. Results: In the first 2 years after initial treatment, IMRT is not cost-effective compared with 3D-CRT, given an average ICER of $101,100 per QALY gained. However, over 15 years (remaining lifetime on the basis of average life expectancy of a 65-year-old), IMRT is more cost-effective at $34,523 per QALY gained. Conclusion: Although HNC patients receiving IMRT will likely experience reduced xerostomia and dysphagia symptoms, the small quality-of-life benefit associated with IMRT is not cost-effective in the short term but may be cost-effective over a patient's lifetime, assuming benefits persist over time and patients are healthy and likely to live for a sustained period. Additional data quantifying the long-term benefits of IMRT, however, are needed.

  7. Attrition Cost Model Instruction Manual

    Science.gov (United States)

    Yanagiura, Takeshi

    2012-01-01

    This instruction manual explains in detail how to use the Attrition Cost Model program, which estimates the cost of student attrition for a state's higher education system. Programmed with SAS, this model allows users to instantly calculate the cost of attrition and the cumulative attrition rate that is based on the most recent retention and…

  8. Finite lifetime fragment model for synchronic band formation in dust tails of comets

    Energy Technology Data Exchange (ETDEWEB)

    Nishioka, Kimihiko; Watanabe, Junichi (Olympus Optical Co., Ltd., Tokyo (Japan) National Astronomical Observatory, Mitaka (Japan))

    1990-10-01

    Synchronic band (SYB) formation in comet dust tails is explained on the basis of a finite lifetime fragment model. Parent particles ejected from the comet nucleus break up at various times, and fragments with a finite lifetime are produced. The observed SYB is produced by the new fragments; it is formed within the lifetime. The model has been applied to SYBs in three comets, and the SYB particle lifetime was found to range from 25 to 70 days. The model describes well the shape of a SYB of Comet West. 14 refs.

  9. Achieving high performance polymer optoelectronic devices for high efficiency, long lifetime and low fabrication cost

    Science.gov (United States)

    Huang, Jinsong

    This thesis described three types of organic optoelectronic devices: polymer light emitting diodes (PLED), polymer photovoltaic solar cell, and organic photo detector. The research in this work focuses improving their performance including device efficiency, operation lifetime simplifying fabrication process. With further understanding in PLED device physics, we come up new device operation model and improved device architecture design. This new method is closely related to understanding of the science and physics at organic/metal oxide and metal oxide/metal interface. In our new device design, both material and interface are considered in order to confine and balance all injected carriers, which has been demonstrated very be successful in increasing device efficiency. We created two world records in device efficiency: 18 lm/W for white emission fluorescence PLED, 22 lm/W for red emission phosphorescence PLED. Slow solvent drying process has been demonstrated to significantly increase device efficiency in poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C 61-butyric acid methyl ester (PCBM) mixture polymer solar cell. From the mobility study by time of flight, the increase of efficiency can be well correlated to the improved carrier transport property due to P3HT crystallization during slow solvent drying. And it is found that, similar to PLED, balanced carrier mobility is essential in high efficient polymer solar cell. There is also a revolution in our device fabrication method. A unique device fabrication method is presented by an electronic glue based lamination process combined with interface modification as a one-step polymer solar cell fabrication process. It can completely skip the thermal evaporation process, and benefit device lifetime by several merits: no air reactive. The device obtained is metal free, semi-transparent, flexible, self-encapsulated, and comparable efficiency with that by regular method. We found the photomultiplication (PM) phenomenon in C

  10. Cost and Performance Assumptions for Modeling Electricity Generation Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Tidball, Rick [ICF International, Fairfax, VA (United States); Bluestein, Joel [ICF International, Fairfax, VA (United States); Rodriguez, Nick [ICF International, Fairfax, VA (United States); Knoke, Stu [ICF International, Fairfax, VA (United States)

    2010-11-01

    The goal of this project was to compare and contrast utility scale power plant characteristics used in data sets that support energy market models. Characteristics include both technology cost and technology performance projections to the year 2050. Cost parameters include installed capital costs and operation and maintenance (O&M) costs. Performance parameters include plant size, heat rate, capacity factor or availability factor, and plant lifetime. Conventional, renewable, and emerging electricity generating technologies were considered. Six data sets, each associated with a different model, were selected. Two of the data sets represent modeled results, not direct model inputs. These two data sets include cost and performance improvements that result from increased deployment as well as resulting capacity factors estimated from particular model runs; other data sets represent model input data. For the technologies contained in each data set, the levelized cost of energy (LCOE) was also evaluated, according to published cost, performance, and fuel assumptions.

  11. Cost and Performance Assumptions for Modeling Electricity Generation Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Tidball, R.; Bluestein, J.; Rodriguez, N.; Knoke, S.

    2010-11-01

    The goal of this project was to compare and contrast utility scale power plant characteristics used in data sets that support energy market models. Characteristics include both technology cost and technology performance projections to the year 2050. Cost parameters include installed capital costs and operation and maintenance (O&M) costs. Performance parameters include plant size, heat rate, capacity factor or availability factor, and plant lifetime. Conventional, renewable, and emerging electricity generating technologies were considered. Six data sets, each associated with a different model, were selected. Two of the data sets represent modeled results, not direct model inputs. These two data sets include cost and performance improvements that result from increased deployment as well as resulting capacity factors estimated from particular model runs; other data sets represent model input data. For the technologies contained in each data set, the levelized cost of energy (LCOE) was also evaluated, according to published cost, performance, and fuel assumptions.

  12. Recording Lifetime Behavior and Movement in an Invertebrate Model

    Science.gov (United States)

    Zou, Sige; Liedo, Pablo; Altamirano-Robles, Leopoldo; Cruz-Enriquez, Janeth; Morice, Amy; Ingram, Donald K.; Kaub, Kevin; Papadopoulos, Nikos; Carey, James R.

    2011-01-01

    Characterization of lifetime behavioral changes is essential for understanding aging and aging-related diseases. However, such studies are scarce partly due to the lack of efficient tools. Here we describe and provide proof of concept for a stereo vision system that classifies and sequentially records at an extremely fine scale six different behaviors (resting, micro-movement, walking, flying, feeding and drinking) and the within-cage (3D) location of individual tephritid fruit flies by time-of-day throughout their lives. Using flies fed on two different diets, full sugar-yeast and sugar-only diets, we report for the first time their behavioral changes throughout their lives at a high resolution. We have found that the daily activity peaks at the age of 15–20 days and then gradually declines with age for flies on both diets. However, the overall daily activity is higher for flies on sugar-only diet than those on the full diet. Flies on sugar-only diet show a stronger diurnal localization pattern with higher preference to staying on the top of the cage during the period of light-off when compared to flies on the full diet. Clustering analyses of age-specific behavior patterns reveal three distinct young, middle-aged and old clusters for flies on each of the two diets. The middle-aged groups for flies on sugar-only diet consist of much younger age groups when compared to flies on full diet. This technology provides research opportunities for using a behavioral informatics approach for understanding different ways in which behavior, movement, and aging in model organisms are mutually affecting. PMID:21559058

  13. Reliability estimation and remaining useful lifetime prediction for bearing based on proportional hazard model

    Institute of Scientific and Technical Information of China (English)

    王鹭; 张利; 王学芝

    2015-01-01

    As the central component of rotating machine, the performance reliability assessment and remaining useful lifetime prediction of bearing are of crucial importance in condition-based maintenance to reduce the maintenance cost and improve the reliability. A prognostic algorithm to assess the reliability and forecast the remaining useful lifetime (RUL) of bearings was proposed, consisting of three phases. Online vibration and temperature signals of bearings in normal state were measured during the manufacturing process and the most useful time-dependent features of vibration signals were extracted based on correlation analysis (feature selection step). Time series analysis based on neural network, as an identification model, was used to predict the features of bearing vibration signals at any horizons (feature prediction step). Furthermore, according to the features, degradation factor was defined. The proportional hazard model was generated to estimate the survival function and forecast the RUL of the bearing (RUL prediction step). The positive results show that the plausibility and effectiveness of the proposed approach can facilitate bearing reliability estimation and RUL prediction.

  14. A Real Options Approach to Quantity and Cost Optimization for Lifetime and Bridge Buys of Parts

    Science.gov (United States)

    2015-05-01

    options in that they apply to tangible assets that are not typically traded as securities. • Unlike conventional net present value analysis...buys play a role in nearly every part obsolescence management portfolio. • Advantages of Lifetime Buys: – Design modifications and re-qualification... value of an option would be trivial to determine. - However, everything is uncertain and the future returns are generally highly asymmetric (upside

  15. Lifetime-Temperature Rise Model for the Evaluation of Degradation in Electric Connections/Contacts

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.T.; Kim, N.J. [Daejin University, Pochon (Korea)

    2002-02-01

    In this paper, 'lifetime-temperature rise model' based on the 'lifetime-resistance model' is theoretically proposed, in order to find out the evaluation method of degradation and the residual lifetime by use of infrared image camera for electric connections/contacts. Two assumptions have been builded up for the 'lifetime-temperature rise model' ; one is associated with the linear relationship between the temperature rise {delta}K and contact resistance, and the other the functional relationship between the temperature of electric connections/contacts and the operating time presenting in the 'lifetime-resistance model'. To prove the proposed model, experiments have been performed for various electric connections/contacts. >From the experimental results, measured values were quite similar to the calculated values, which proved the above-mentioned two assumptions. Therefore, by use of 'lifetime-temperature rise model', it is possible to estimate the trend of degradation and the residual lifetime for electric connections/contacts through the temperature measurements. (author). 5 refs., 7 figs., 3 tabs.

  16. Hydropower Baseline Cost Modeling

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, Patrick W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zhang, Qin Fen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DeNeale, Scott T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Chalise, Dol Raj [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Centurion, Emma E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    Recent resource assessments conducted by the United States Department of Energy have identified significant opportunities for expanding hydropower generation through the addition of power to non-powered dams and on undeveloped stream-reaches. Additional interest exists in the powering of existing water resource infrastructure such as conduits and canals, upgrading and expanding existing hydropower facilities, and the construction new pumped storage hydropower. Understanding the potential future role of these hydropower resources in the nation’s energy system requires an assessment of the environmental and techno-economic issues associated with expanding hydropower generation. To facilitate these assessments, this report seeks to fill the current gaps in publically available hydropower cost-estimating tools that can support the national-scale evaluation of hydropower resources.

  17. Overcoming bottlenecks of enzymatic biofuel cell cathodes: crude fungal culture supernatant can help to extend lifetime and reduce cost.

    Science.gov (United States)

    Sané, Sabine; Jolivalt, Claude; Mittler, Gerhard; Nielsen, Peter J; Rubenwolf, Stefanie; Zengerle, Roland; Kerzenmacher, Sven

    2013-07-01

    Enzymatic biofuel cells (BFCs) show great potential for the direct conversion of biochemically stored energy from renewable biomass resources into electricity. However, enzyme purification is time-consuming and expensive. Furthermore, the long-term use of enzymatic BFCs is hindered by enzyme degradation, which limits their lifetime to only a few weeks. We show, for the first time, that crude culture supernatant from enzyme-secreting microorganisms (Trametes versicolor) can be used without further treatment to supply the enzyme laccase to the cathode of a mediatorless BFC. Polarization curves show that there is no significant difference in the cathode performance when using crude supernatant that contains laccase compared to purified laccase in culture medium or buffer solution. Furthermore, we demonstrate that the oxygen reduction activity of this enzymatic cathode can be sustained over a period of at least 120 days by periodic resupply of crude culture supernatant. This is more than five times longer than control cathodes without the resupply of culture supernatant. During the operation period of 120 days, no progressive loss of potential is observed, which suggests that significantly longer lifetimes than shown in this work may be possible. Our results demonstrate the possibility to establish simple, cost efficient, and mediatorless enzymatic BFC cathodes that do not require expensive enzyme purification procedures. Furthermore, they show the feasibility of an enzymatic BFC with an extended lifetime, in which self-replicating microorganisms provide the electrode with catalytically active enzymes in a continuous or periodic manner.

  18. Estimated Lifetime Medical and Work-Loss Costs of Emergency Department-Treated Nonfatal Injuries--United States, 2013.

    Science.gov (United States)

    Florence, Curtis; Haegerich, Tamara; Simon, Thomas; Zhou, Chao; Luo, Feijun

    2015-10-02

    A large number of nonfatal injuries are treated in U.S. emergency departments (EDs) every year. CDC's National Center for Health Statistics estimates that approximately 29% of all ED visits in 2010 were for injuries. To assess the economic impact of ED-treated injuries, CDC examined injury data from the National Electronic Injury Surveillance System--All Injury Program (NEISS-AIP) for 2013, as well as injury-related lifetime medical and work-loss costs from the Web-Based Injury Statistics Query and Reporting System (WISQARS). NEISS-AIP collects data from a nationally representative sample of EDs, using specific guidelines for recording the primary diagnosis and mechanism of injury. Number of injuries, crude- and age-specific injury rates, and total lifetime work-loss costs and medical costs were calculated for ED-treated injuries, stratified by sex, age groups, and intent and mechanism of injury. ED-treated injuries were further classified as those that were subsequently hospitalized or treated and released. The rate of hospitalized injuries was 950.8 per 100,000, and the rate of treated and released injuries was 8,549.8 per 100,000. Combined medical and work-loss costs for all ED-treated injuries (both hospitalized and treated and released) were $456.9 billion, or approximately 68% of the total costs of $671 billion associated with all fatal and ED-treated injuries. The substantial economic burden associated with nonfatal injuries underscores the need for effective prevention strategies.

  19. PV O&M Cost Model and Cost Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Andy

    2017-03-15

    This is a presentation on PV O&M cost model and cost reduction for the annual Photovoltaic Reliability Workshop (2017), covering estimating PV O&M costs, polynomial expansion, and implementation of Net Present Value (NPV) and reserve account in cost models.

  20. The direct cost of traumatic secretion transfer in hermaphroditic land snails: individuals stabbed with a love dart decrease lifetime fecundity.

    Science.gov (United States)

    Kimura, Kazuki; Chiba, Satoshi

    2015-04-07

    Several taxa of simultaneously hermaphroditic land snails exhibit a conspicuous mating behaviour, the so-called shooting of love darts. During mating, such land snail species transfer a specific secretion by stabbing a mating partner's body with the love dart. It has been shown that sperm donors benefit from this traumatic secretion transfer, because the secretions manipulate the physiology of a sperm recipient and increase the donors' fertilization success. However, it is unclear whether reception of dart shooting is costly to the recipients. Therefore, the effect of sexual conflict and antagonistic arms races on the evolution of traumatic secretion transfer in land snails is still controversial. To examine this effect, we compared lifetime fecundity and longevity between the individuals that received and did not receive dart shooting from mating partners in Bradybaena pellucida. Our experiments showed that the dart-receiving snails suffered reduction in lifetime fecundity and longevity. These results suggest that the costly mating behaviour, dart shooting, generates conflict between sperm donors and recipients and that sexually antagonistic arms races have contributed to the diversification of the morphological and behavioural traits relevant to dart shooting. Our findings also support theories suggesting a violent escalation of sexual conflict in hermaphroditic animals.

  1. Multiphysics modelling, quantum chemistry and risk analysis for corrosion inhibitor design and lifetime prediction.

    Science.gov (United States)

    Taylor, C D; Chandra, A; Vera, J; Sridhar, N

    2015-01-01

    Organic corrosion inhibitors can provide an effective means to extend the life of equipment in aggressive environments, decrease the environmental, economic, health and safety risks associated with corrosion failures and enable the use of low cost steels in place of corrosion resistant alloys. To guide the construction of advanced models for the design and optimization of the chemical composition of organic inhibitors, and to develop predictive tools for inhibitor performance as a function of alloy and environment, a multiphysics model has been constructed following Staehle's principles of "domains and microprocesses". The multiphysics framework provides a way for science-based modelling of the various phenomena that impact inhibitor efficiency, including chemical thermodynamics and speciation, oil/water partitioning, effect of the inhibitor on multiphase flow, surface adsorption and self-assembled monolayer formation, and the effect of the inhibitor on cathodic and anodic reaction pathways. The fundamental tools required to solve the resulting modelling from a first-principles perspective are also described. Quantification of uncertainty is significant to the development of lifetime prediction models, due to their application for risk management. We therefore also discuss how uncertainty analysis can be coupled with the first-principles approach laid out in this paper.

  2. Life cycle monitoring of lithium-ion polymer batteries using cost-effective thermal infrared sensors with applications for lifetime prediction

    Science.gov (United States)

    Zhou, Xunfei; Malik, Anav; Hsieh, Sheng-Jen

    2017-05-01

    Lithium-ion batteries have become indispensable parts of our lives for their high-energy density and long lifespan. However, failure due to from abusive usage conditions, flawed manufacturing processes, and aging and adversely affect battery performance and even endanger people and property. Therefore, battery cells that are failing or reaching their end-of-life need to be replaced. Traditionally, battery lifetime prediction is achieved by analyzing data from current, voltage and impedance sensors. However, such a prognostic system is expensive to implement and requires direct contact. In this study, low-cost thermal infrared sensors were used to acquire thermographic images throughout the entire lifetime of small scale lithium-ion polymer batteries (410 cycles). The infrared system (non-destructive) took temperature readings from multiple batteries during charging and discharging cycles of 1C. Thermal characteristics of the batteries were derived from the thermographic images. A time-dependent and spatially resolved temperature mapping was obtained and quantitatively analyzed. The developed model can predict cycle number using the first 10 minutes of surface temperature data acquired through infrared imaging at the beginning of the cycle, with an average error rate of less than 10%. This approach can be used to correlate thermal characteristics of the batteries with life cycles, and to propose cost-effective thermal infrared imaging applications in battery prognostic systems.

  3. Deployment-based lifetime optimization model for homogeneous Wireless Sensor Network under retransmission.

    Science.gov (United States)

    Li, Ruiying; Liu, Xiaoxi; Xie, Wei; Huang, Ning

    2014-12-10

    Sensor-deployment-based lifetime optimization is one of the most effective methods used to prolong the lifetime of Wireless Sensor Network (WSN) by reducing the distance-sensitive energy consumption. In this paper, data retransmission, a major consumption factor that is usually neglected in the previous work, is considered. For a homogeneous WSN, monitoring a circular target area with a centered base station, a sensor deployment model based on regular hexagonal grids is analyzed. To maximize the WSN lifetime, optimization models for both uniform and non-uniform deployment schemes are proposed by constraining on coverage, connectivity and success transmission rate. Based on the data transmission analysis in a data gathering cycle, the WSN lifetime in the model can be obtained through quantifying the energy consumption at each sensor location. The results of case studies show that it is meaningful to consider data retransmission in the lifetime optimization. In particular, our investigations indicate that, with the same lifetime requirement, the number of sensors needed in a non-uniform topology is much less than that in a uniform one. Finally, compared with a random scheme, simulation results further verify the advantage of our deployment model.

  4. Temperature dependency of the silicon heterojunction lifetime model based on the amphoteric nature of dangling bonds

    Science.gov (United States)

    Vasudevan, R.; Poli, I.; Deligiannis, D.; Zeman, M.; Smets, A. H. M.

    2016-11-01

    This work adapts a model to simulate the carrier injection dependent minority carrier lifetime of crystalline silicon passivated with hydrogenated amorphous silicon at elevated temperatures. Two existing models that respectively calculate the bulk lifetime and surface recombination velocity are used and the full temperature dependency of these models are explored. After a thorough description of these temperature dependencies, experimental results using this model show that the minority carrier lifetime changes upon annealing of silicon heterojunction structures are not universal. Furthermore, comparisons of the temperature dependent model to using the room temperature model at elevated temperatures is given and significant differences are observed when using temperatures above 100 °C. This shows the necessity of taking temperature effects into account during in-situ annealing experiments.

  5. Wind Turbine Blade Life-Time Assessment Model for Preventive Planning of Operation and Maintenance

    Directory of Open Access Journals (Sweden)

    Mihai Florian

    2015-09-01

    Full Text Available Out of the total wind turbine failure events, blade damage accounts for a substantial part, with some studies estimating it at around 23%. Current operation and maintenance (O&M practices typically make use of corrective type maintenance as the basic approach, implying high costs for repair and replacement activities as well as large revenue losses, mainly in the case of offshore wind farms. The recent development and evolution of condition monitoring techniques, as well as the fact that an increasing number of installed turbines are equipped with online monitoring systems, offers a large amount of information on the blades structural health to the decision maker. Further, inspections of the blades are often performed in connection with service. In light of the obtained information, a preventive type of maintenance becomes feasible, with the potential of predicting the blades remaining life to support O&M decisions for avoiding major failure events. The present paper presents a fracture mechanics based model for estimating the remaining life of a wind turbine blade, focusing on the crack propagation in the blades adhesive joints. A generic crack propagation model is built in Matlab based on a Paris law approach. The model is used within a risk-based maintenance decision framework to optimize maintenance planning for the blades lifetime.

  6. Deriving estimates of individual variability in genetic potentials of performance traits for 3 dairy breeds, using a model of lifetime nutrient partitioning

    DEFF Research Database (Denmark)

    Phuong, H N; Martin, O; de Boer, I J M;

    2015-01-01

    , body reserve usage, and growth for different genotypes of cow. Moreover, it can be used to separate genetic variability in performance between individual cows from environmental noise. The model enables simulation of the effects of a genetic selection strategy on lifetime efficiency of individual cows......, which has a main advantage of including the rearing costs, and thus, can be used to explore the impact of future selection on animal performance and efficiency.......This study explored the ability of an existing lifetime nutrient partitioning model for simulating individual variability in genetic potentials of dairy cows. Generally, the model assumes a universal trajectory of dynamic partitioning of priority between life functions and genetic scaling...

  7. Prediction of the lifetime productive and reproductive performance of Holstein cows managed for different lactation durations, using a model of lifetime nutrient partitioning

    DEFF Research Database (Denmark)

    Gaillard, Charlotte; Martin, O; Blavy, P

    2016-01-01

    The GARUNS model is a lifetime performance model taking into account the changing physiological priorities of an animal during its life and through repeated reproduction cycles. This dynamic and stochastic model has been previously used to predict the productive and reproductive performance of va...

  8. A Departmental Cost-Effectiveness Model.

    Science.gov (United States)

    Holleman, Thomas, Jr.

    In establishing a departmental cost-effectiveness model, the traditional cost-effectiveness model was discussed and equipped with a distant and deflation equation for both benefits and costs. Next, the economics of costing was examined and program costing procedures developed. Then, the model construct was described as it was structured around the…

  9. Lifetime Models for Lithium-ion Batteries used in Virtual Power Plant Applications

    DEFF Research Database (Denmark)

    Stroe, Daniel Ioan

    . Moreover, in this thesis, the use of the electrochemical impedance spectroscopy (EIS) technique was proposed as a method to estimate the pulse power capability decrease, which is caused by ageing, of the tested LFP/C battery cells. The developed lifetime models were used to analyse the degradation......The penetration of wind power into the power system has been increasing in recent years. However, despite its environmental friendliness, the wind power grid integration at a large scale faces several limitations, mainly caused by the characteristics of the wind (i.e. intermittent, variable......-ion batteries are presented in the literature. In this thesis an equivalent-electrical circuit performance-degradation modelling approach was followed to develop the lifetime models for the selected LFP/C battery cells. In order to develop the desired lifetime model, laboratory ageing tests are mandatory...

  10. Cost Model for Digital Preservation: Cost of Digital Migration

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2011-01-01

    The Danish Ministry of Culture has funded a project to set up a model for costing preservation of digital materials held by national cultural heritage institutions. The overall objective of the project was to increase cost effectiveness of digital preservation activities and to provide a basis...... for comparing and estimating future cost requirements for digital preservation. In this study we describe an activity-based costing methodology for digital preservation based on the Open Archice Information System (OAIS) Reference Model. Within this framework, which we denote the Cost Model for Digital...... Preservation (CMDP), the focus is on costing the functional entity Preservation Planning from the OAIS and digital migration activities. In order to estimate these costs we have identified cost-critical activities by analysing the functions in the OAIS model and the flows between them. The analysis has been...

  11. Cost Model for Digital Preservation: Cost of Digital Migration

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2011-01-01

    calculate the cost of different migration scenarios for a series of preservation formats for text, images, sound, video, geodata, and spreadsheets. In order to verify the model it has been tested on cost data from two different migration projects at the Danish National Archives (DNA). The study found...... Preservation (CMDP), the focus is on costing the functional entity Preservation Planning from the OAIS and digital migration activities. In order to estimate these costs we have identified cost-critical activities by analysing the functions in the OAIS model and the flows between them. The analysis has been...... that the OAIS model provides a sound overall framework for the cost breakdown, but that some functions need additional detailing in order to cost activities accurately. Running the two sets of empirical data showed among other things that the model underestimates the cost of manpower-intensive migration...

  12. Potential lifetime cost-effectiveness of catheter-based renal sympathetic denervation in patients with resistant hypertension.

    Science.gov (United States)

    Dorenkamp, Marc; Bonaventura, Klaus; Leber, Alexander W; Boldt, Julia; Sohns, Christian; Boldt, Leif-Hendrik; Haverkamp, Wilhelm; Frei, Ulrich; Roser, Mattias

    2013-02-01

    Recent studies have demonstrated the safety and efficacy of catheter-based renal sympathetic denervation (RDN) for the treatment of resistant hypertension. We aimed to determine the cost-effectiveness of this approach separately for men and women of different ages. A Markov state-transition model accounting for costs, life-years, quality-adjusted life-years (QALYs), and incremental cost-effectiveness was developed to compare RDN with best medical therapy (BMT) in patients with resistant hypertension. The model ran from age 30 to 100 years or death, with a cycle length of 1 year. The efficacy of RDN was modelled as a reduction in the risk of hypertension-related disease events and death. Analyses were conducted from a payer's perspective. Costs and QALYs were discounted at 3% annually. Both deterministic and probabilistic sensitivity analyses were performed. When compared with BMT, RDN gained 0.98 QALYs in men and 0.88 QALYs in women 60 years of age at an additional cost of €2589 and €2044, respectively. As the incremental cost-effectiveness ratios increased with patient age, RDN consistently yielded more QALYs at lower costs in lower age groups. Considering a willingness-to-pay threshold of €35 000/QALY, there was a 95% probability that RDN would remain cost-effective up to an age of 78 and 76 years in men and women, respectively. Cost-effectiveness was influenced mostly by the magnitude of effect of RDN on systolic blood pressure, the rate of RDN non-responders, and the procedure costs of RDN. Renal sympathetic denervation is a cost-effective intervention for patients with resistant hypertension. Earlier treatment produces better cost-effectiveness ratios.

  13. Modeling and optimization of the lifetime of technologies

    CERN Document Server

    Hritonenko, Natali

    1996-01-01

    Modern economic growth is characterized by structural changes based on the introduction of new technologies into economics. The replacement and renova­ tion of technologies in industrial environments undergoing technical change is clearly one of the key aspects of economic development. The mathematical modeling of evolutionary economics under technical change (TC) has been rigorously considered by many authors during last decades. There is a wide variety of economic approaches and models describing different aspects of technical change. Among these are the models of embodied technical progress [19], [35], [70], [129], endogenous growth models [94], [102], the models of technological innovations [31], [32], [41], and others. The perspective self­ organization evolutionary approach is developed in [20], [38], [122], [123], [124], [126], which unites the aspects of diffusion of new technologies, technological and behavioral diversity of firms, learning mechanisms, age-dependent effects, and other important fea...

  14. Grid-connected polymer solar panels: initial considerations of cost, lifetime, and practicality

    DEFF Research Database (Denmark)

    Medford, Andrew James; Lilliedal, Mathilde Raad; Jørgensen, Mikkel;

    2010-01-01

    Large solar panels were constructed from polymer solar cell modules prepared using full roll-to-roll (R2R) manufacture based on the previously published ProcessOne. The individual flexible polymer solar modules comprising multiple serially connected single cell stripes were joined electrically...... station and their output was grid connected between testing. Several generations of polymer solar cells and panel constructions were tested in this context to optimize the production of polymer solar panels. Cells lacking a R2R barrier layer were found to degrade due to diffusion of oxygen after less than...... that the inclusion of a thin protective foil between the cell and the barrier foil is critical. The findings provide a preliminary foundation for the production and optimization of large-area polymer solar panels and also enabled a cost analysis of solar panels based on polymer solar cells....

  15. Cost Model for Digital Preservation: Cost of Digital Migration

    Directory of Open Access Journals (Sweden)

    Ulla Bøgvad Kejser

    2011-03-01

    Full Text Available The Danish Ministry of Culture has funded a project to set up a model for costing preservation of digital materials held by national cultural heritage institutions. The overall objective of the project was to increase cost effectiveness of digital preservation activities and to provide a basis for comparing and estimating future cost requirements for digital preservation. In this study we describe an activity-based costing methodology for digital preservation based on the Open Archice Information System (OAIS Reference Model. Within this framework, which we denote the Cost Model for Digital Preservation (CMDP, the focus is on costing the functional entity Preservation Planning from the OAIS and digital migration activities. In order to estimate these costs we have identified cost-critical activities by analysing the functions in the OAIS model and the flows between them. The analysis has been supplemented with findings from the literature, and our own knowledge and experience. The identified cost-critical activities have subsequently been deconstructed into measurable components, cost dependencies have been examined, and the resulting equations expressed in a spreadsheet. Currently the model can calculate the cost of different migration scenarios for a series of preservation formats for text, images, sound, video, geodata, and spreadsheets. In order to verify the model it has been tested on cost data from two different migration projects at the Danish National Archives (DNA. The study found that the OAIS model provides a sound overall framework for the cost breakdown, but that some functions need additional detailing in order to cost activities accurately. Running the two sets of empirical data showed among other things that the model underestimates the cost of manpower-intensive migration projects, while it reinstates an often underestimated cost, which is the cost of developing migration software. The model has proven useful for estimating the

  16. How Much? Cost Models for Online Education.

    Science.gov (United States)

    Lorenzo, George

    2001-01-01

    Reviews some of the research being done in the area of cost models for online education. Describes a cost analysis handbook; an activity-based costing model that was based on an economic model for traditional instruction at the Indiana University Purdue University Indianapolis; and blending other costing models. (LRW)

  17. Interpreting aerosol lifetimes using the GEOS-Chem model and constraints from radionuclide measurements

    Science.gov (United States)

    Croft, B.; Pierce, J. R.; Martin, R. V.

    2014-04-01

    Aerosol removal processes control global aerosol abundance, but the rate of that removal remains uncertain. A recent study of aerosol-bound radionuclide measurements after the Fukushima Daiichi nuclear power plant accident documents 137Cs removal (e-folding) times of 10.0-13.9 days, suggesting that mean aerosol lifetimes in the range of 3-7 days in global models might be too short by a factor of two. In this study, we attribute this discrepancy to differences between the e-folding and mean aerosol lifetimes. We implement a simulation of 137Cs and 133Xe into the GEOS-Chem chemical transport model and examine the removal rates for the Fukushima case. We find a general consistency between modelled and measured e-folding times. The simulated 137Cs global burden e-folding time is about 14 days. However, the simulated mean lifetime of aerosol-bound 137Cs over a 6-month post-accident period is only 1.8 days. We find that the mean lifetime depends strongly on the removal rates in the first few days after emissions, before the aerosols leave the boundary layer and are transported to altitudes and latitudes where lifetimes with respect to wet removal are longer by a few orders of magnitude. We present sensitivity simulations that demonstrate the influence of differences in altitude and location of the radionuclides on the mean lifetime. Global mean lifetimes are shown to strongly depend on the altitude of injection. The global mean 137Cs lifetime is more than one order of magnitude greater for the injection at 7 km than into the boundary layer above the Fukushima site. Instantaneous removal rates are slower during the first few days after the emissions for a free tropospheric versus boundary layer injection and this strongly controls the mean lifetimes. Global mean aerosol lifetimes for the GEOS-Chem model are 3-6 days, which is longer than that for the 137Cs injected at the Fukushima site (likely due to precipitation shortly after Fukushima emissions), but similar to the

  18. Modeling Customer Lifetimes with Multiple Causes of Churn

    OpenAIRE

    Michael Braun; David A. Schweidel

    2011-01-01

    Customer retention and customer churn are key metrics of interest to marketers, but little attention has been placed on linking the different reasons for which customers churn to their value to a contractual service provider. In this paper, we put forth a hierarchical competing-risk model to jointly model when customers choose to terminate their service and why. Some of these reasons for churn can be influenced by the firm (e.g., service problems or price–value trade-offs), but others are unc...

  19. A low cost fluorescence lifetime measurement system based on SPAD detectors and FPGA processing

    Science.gov (United States)

    Franch, N.; Alonso, O.; Canals, J.; Vilà, A.; Dieguez, A.

    2017-02-01

    This work presents a low cost fluorescence life time measurement system, aimed at carrying out fast diagnostic tests through label detection in a portable system so it can be used in a medical consultation, within a short time span. The system uses Time Correlated Single Photon Counting (TCSPC), measuring the arrival time of individual photons and building a histogram of those times, showing the fluorescence decay of the label which is characteristic of each fluorescent substance. The system is implemented using a Xilinx FPGA which controls the experiment and includes a Time to Digital Converter (TDC) to perform measurements with a resolution in the order of tenths of picoseconds. Also included are a laser diode and the driving electronics to generate short pulses as well as a HV-CMOS implemented Single Photon Avalanche Diode (SPAD) as a high gain sensor. The system is entirely configurable so it can easily be adapted to the target label molecule and measurement needs. The histogram is constructed within the FPGA and can then be read as convenient. Various performance parameters are also shown, as well as experimental measurements of a quantum dot fluorescence decay as a proof of concept.

  20. Grid-connected polymer solar panels: initial considerations of cost, lifetime, and practicality.

    Science.gov (United States)

    Medford, Andrew J; Lilliedal, Mathilde R; Jørgensen, Mikkel; Aarø, Dennis; Pakalski, Heinz; Fyenbo, Jan; Krebs, Frederik C

    2010-09-13

    Large solar panels were constructed from polymer solar cell modules prepared using full roll-to-roll (R2R) manufacture based on the previously published ProcessOne. The individual flexible polymer solar modules comprising multiple serially connected single cell stripes were joined electrically and laminated between a 4 mm tempered glass window and black Tetlar foil using two sheets of 0.5 mm thick ethylene vinyl acetate (EVA). The panels produced up to 8 W with solar irradiance of ~960 Wm⁻², and had outer dimensions of 1 m x 1.7 m with active areas up to 9180 cm². Panels were mounted on a tracking station and their output was grid connected between testing. Several generations of polymer solar cells and panel constructions were tested in this context to optimize the production of polymer solar panels. Cells lacking a R2R barrier layer were found to degrade due to diffusion of oxygen after less than a month, while R2R encapsulated cells showed around 50% degradation after 6 months but suffered from poor performance due to de-lamination during panel production. A third generation of panels with various barrier layers was produced to optimize the choice of barrier foil and it was found that the inclusion of a thin protective foil between the cell and the barrier foil is critical. The findings provide a preliminary foundation for the production and optimization of large-area polymer solar panels and also enabled a cost analysis of solar panels based on polymer solar cells.

  1. Cost Model for Digital Curation: Cost of Digital Migration

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2009-01-01

    activities by analysing the OAIS Model, and supplemented this analysis with findings from other models, literature and own experience. To verify the model it has been tested on two sets of data from a normalisation project and a migration project at the Danish National Archives. The study found that the OAIS...... for digital preservation and to increase cost effectiveness of digital preservation activities. In this study we describe an activity based costing methodology for digital preservation based on the OAIS Reference Model. In order to estimate the cost of digital migrations we have identified cost critical...... model provides a sound overall framework for cost breakdown, but that some functions, especially when it comes to performing and evaluating the actual migration, need additional detailing in order to cost activities accurately....

  2. Cost Model for Digital Curation: Cost of Digital Migration

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2009-01-01

    The Danish Ministry of Culture is currently funding a project to set up a model for costing preservation of digital materials held by national cultural heritage institutions. The overall objective of the project is to provide a basis for comparing and estimating future financial requirements...... for digital preservation and to increase cost effectiveness of digital preservation activities. In this study we describe an activity based costing methodology for digital preservation based on the OAIS Reference Model. In order to estimate the cost of digital migrations we have identified cost critical...... model provides a sound overall framework for cost breakdown, but that some functions, especially when it comes to performing and evaluating the actual migration, need additional detailing in order to cost activities accurately....

  3. Lifetime prediction modeling of airfoils for advanced power generation

    Science.gov (United States)

    Karaivanov, Ventzislav Gueorguiev

    The use of gases produced from coal as a turbine fuel offers an attractive means for efficiently generating electric power from our Nation's most abundant fossil fuel resource. The oxy-fuel and hydrogen-fired turbine concepts promise increased efficiency and low emissions on the expense of increased turbine inlet temperature (TIT) and different working fluid. Developing the turbine technology and materials is critical to the creation of these near-zero emission power generation technologies. A computational methodology, based on three-dimensional finite element analysis (FEA) and damage mechanics is presented for predicting the evolution of creep and fatigue in airfoils. We took a first look at airfoil thermal distributions in these advanced turbine systems based on CFD analysis. The damage mechanics-based creep and fatigue models were implemented as user modified routine in commercial package ANSYS. This routine was used to visualize the creep and fatigue damage evolution over airfoils for hydrogen-fired and oxy-fuel turbines concepts, and regions most susceptible to failure were indentified. Model allows for interaction between creep and fatigue damage thus damage due to fatigue and creep processes acting separately in one cycle will affect both the fatigue and creep damage rates in the next cycle. Simulation results were presented for various thermal conductivity of the top coat. Surface maps were created on the airfoil showing the development of the TGO scale and the Al depletion of the bond coat. In conjunction with model development, laboratory-scale experimental validation was executed to evaluate the influence of operational compressive stress levels on the performance of the TBC system. TBC coated single crystal coupons were exposed isothermally in air at 900, 1000, 1100oC with and without compressive load. Exposed samples were cross-sectioned and evaluated with scanning electron microscope (SEM). Performance data was collected based on image analysis

  4. Implementing a trustworthy cost-accounting model.

    Science.gov (United States)

    Spence, Jay; Seargeant, Dan

    2015-03-01

    Hospitals and health systems can develop an effective cost-accounting model and maximize the effectiveness of their cost-accounting teams by focusing on six key areas: Implementing an enhanced data model. Reconciling data efficiently. Accommodating multiple cost-modeling techniques. Improving transparency of cost allocations. Securing department manager participation. Providing essential education and training to staff members and stakeholders.

  5. Preliminary Multivariable Cost Model for Space Telescopes

    Science.gov (United States)

    Stahl, H. Philip

    2010-01-01

    Parametric cost models are routinely used to plan missions, compare concepts and justify technology investments. Previously, the authors published two single variable cost models based on 19 flight missions. The current paper presents the development of a multi-variable space telescopes cost model. The validity of previously published models are tested. Cost estimating relationships which are and are not significant cost drivers are identified. And, interrelationships between variables are explored

  6. 874 CONSTRUCTION COST MODELS FOR HIGHRISE OFFICE ...

    African Journals Online (AJOL)

    USER

    2015-10-28

    Oct 28, 2015 ... Ethiopian Journal of Environmental Studies & Management 8(Suppl. 2): 874 – 880, 2015. ... Key Words: Cost, Highrise, Models, Nigeria, Office, Construction. Introduction .... the modern trend in cost analysis and cost planning ...

  7. On modeling of lifetime data using two-parameter Gamma and Weibull distributions

    NARCIS (Netherlands)

    Shanker, Rama; Shukla, Kamlesh Kumar; Shanker, Ravi; Leonida, Tekie Asehun

    2016-01-01

    The analysis and modeling of lifetime data are crucial in almost all applied sciences including medicine, insurance, engineering, behavioral sciences and finance, amongst others. The main objective of this paper is to have a comparative study of two-parameter gamma and Weibull distributions for mode

  8. Simple Derivation of the Lifetime and the Distribution of Faces for a Binary Subdivision Model

    CERN Document Server

    Hayashi, Yukio

    2015-01-01

    The iterative random subdivision of rectangles is used as a generation model of networks in physics, computer science, and urban planning. However, these researches were independent. We consider some relations in them, and derive fundamental properties for the average lifetime depending on birth-time and the balanced distribution of rectangle faces.

  9. Lifetime prediction for the subsurface crack propagation using three-dimensional dynamic FEA model

    Science.gov (United States)

    Yin, Yuan; Chen, Yun-Xia; Liu, Le

    2017-03-01

    The subsurface crack propagation is one of the major interests for gear system research. The subsurface crack propagation lifetime is the number of cycles remaining for a spall to appear, which can be obtained through either stress intensity factor or accumulated plastic strain analysis. In this paper, the heavy loads are applied to the gear system. When choosing stress intensity factor, the high compressive stress suppresses Mode I stress intensities and severely reduces Mode II stress intensities in the heavily loaded lubricated contacts. Such that, the accumulated plastic strain is selected to calculate the subsurface crack propagation lifetime from the three-dimensional FEA model through ANSYS Workbench transient analysis. The three-dimensional gear FEA dynamic model with the subsurface crack is built through dividing the gears into several small elements. The calculation of the total cycles of the elements is proposed based on the time-varying accumulated plastic strain, which then will be used to calculate the subsurface crack propagation lifetime. During this process, the demonstration from a subsurface crack to a spall can be uncovered. In addition, different sizes of the elements around the subsurface crack are compared in this paper. The influences of the frictional coefficient and external torque on the crack propagation lifetime are also discussed. The results show that the lifetime of crack propagation decreases significantly when the external load T increasing from 100 N m to 150 N m. Given from the distributions of the accumulated plastic strain, the lifetime shares no significant difference when the frictional coefficient f ranging in 0.04-0.06.

  10. Population Dynamics and Cost-Benefit Analysis. An Attempt to Relate Population Dynamics via Lifetime Reproductive Success to Short-Term Decisions

    NARCIS (Netherlands)

    Tinbergen, J.M.; Balen, J.H. van; Drent, P.J.; Cavé, A.J.; Mertens, J.A.L.; Boer-Hazewinkel, J. den

    1987-01-01

    1. The aim of this article is to explore whether cost-benefit analysis of behaviour may help to understand the population dynamics of a species. The Great Tit is taken as an example. 2. The lifetime reproductive success in different populations of Great Tits amounts from 0.7 (Hoge Veluwe, Wytham) to

  11. Return of feature-based cost modeling

    Science.gov (United States)

    Creese, Robert C.; Patrawala, Taher B.

    1998-10-01

    Feature Based Cost Modeling is thought of as a relative new approach to cost modeling, but feature based cost modeling had considerable development in the 1950's. Considerable work was published in the 1950's by Boeing on cost for various casting processes--sand casting, die casting, investment casting and permanent mold casting--as a function of a single casting feature, casting volume. Additional approaches to feature based cost modeling have been made, and this work is a review of previous works and a proposed integrated model to feature based cost modeling.

  12. Bilayer Suspension Plasma-Sprayed Thermal Barrier Coatings with Enhanced Thermal Cyclic Lifetime: Experiments and Modeling

    Science.gov (United States)

    Gupta, Mohit; Kumara, Chamara; Nylén, Per

    2017-08-01

    Suspension plasma spraying (SPS) has been shown as a promising process to produce porous columnar strain tolerant coatings for thermal barrier coatings (TBCs) in gas turbine engines. However, the highly porous structure is vulnerable to crack propagation, especially near the topcoat-bondcoat interface where high stresses are generated due to thermal cycling. A topcoat layer with high toughness near the topcoat-bondcoat interface could be beneficial to enhance thermal cyclic lifetime of SPS TBCs. In this work, a bilayer coating system consisting of first a dense layer near the topcoat-bondcoat interface followed by a porous columnar layer was fabricated by SPS using Yttria-stabilised zirconia suspension. The objective of this work was to investigate if the bilayer topcoat architecture could enhance the thermal cyclic lifetime of SPS TBCs through experiments and to understand the effect of the column gaps/vertical cracks and the dense layer on the generated stresses in the TBC during thermal cyclic loading through finite element modeling. The experimental results show that the bilayer TBC had significantly higher lifetime than the single-layer TBC. The modeling results show that the dense layer and vertical cracks are beneficial as they reduce the thermally induced stresses which thus increase the lifetime.

  13. Lifetime growth in wild meerkats: incorporating life history and environmental factors into a standard growth model.

    Science.gov (United States)

    English, Sinéad; Bateman, Andrew W; Clutton-Brock, Tim H

    2012-05-01

    Lifetime records of changes in individual size or mass in wild animals are scarce and, as such, few studies have attempted to model variation in these traits across the lifespan or to assess the factors that affect them. However, quantifying lifetime growth is essential for understanding trade-offs between growth and other life history parameters, such as reproductive performance or survival. Here, we used model selection based on information theory to measure changes in body mass over the lifespan of wild meerkats, and compared the relative fits of several standard growth models (monomolecular, von Bertalanffy, Gompertz, logistic and Richards). We found that meerkats exhibit monomolecular growth, with the best model incorporating separate growth rates before and after nutritional independence, as well as effects of season and total rainfall in the previous nine months. Our study demonstrates how simple growth curves may be improved by considering life history and environmental factors, which may be particularly relevant when quantifying growth patterns in wild populations.

  14. A New Finite Interval Lifetime Distribution Model for Fitting Bathtub-Shaped Failure Rate Curve

    Directory of Open Access Journals (Sweden)

    Xiaohong Wang

    2015-01-01

    Full Text Available This paper raised a new four-parameter fitting model to describe bathtub curve, which is widely used in research on components’ life analysis, then gave explanation of model parameters, and provided parameter estimation method as well as application examples utilizing some well-known lifetime data. By comparative analysis between the new model and some existing bathtub curve fitting model, we can find that the new fitting model is very convenient and its parameters are clear; moreover, this model is of universal applicability which is not only suitable for bathtub-shaped failure rate curves but also applicable for the constant, increasing, and decreasing failure rate curves.

  15. Study of creep-fatigue behavior in a 1000 MW rotor using a phenomenological lifetime model

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Nailong; Wang, Weizhe; Jiang, Jishen; Liu, Yingzheng [School of Mechanical Engineering, Shanghai (China)

    2017-02-15

    In this study, the phenomenological lifetime model was applied to part of an ultra-supercritical steam turbine rotor model to predict its lifetime as a post processing of the finite element method. To validate the accuracy and adaptation of the post processing program, stress strain hysteresis loops of a cylinderal model under service-like load cycle conditions in cycle N = 1 and 300 were constructed, and the comparison of the results with experimental data on the same cylinderal specimen showed them to be satisfactory. The temperature and von Mises stress distributions of the rotor during a startup-running-shutdown-natural cool process were numerically studied using ABAQUS and the damage caused by the interaction of creep and fatigue was subsequently computed and discussed. It was found that the maximum damage appeared at the inlet notch zone, with the blade groove areas and the front notch areas also suffering a large damage amplitude.

  16. Beyond R0: demographic models for variability of lifetime reproductive output.

    Directory of Open Access Journals (Sweden)

    Hal Caswell

    Full Text Available The net reproductive rate R0 measures the expected lifetime reproductive output of an individual, and plays an important role in demography, ecology, evolution, and epidemiology. Well-established methods exist to calculate it from age- or stage-classified demographic data. As an expectation, R0 provides no information on variability; empirical measurements of lifetime reproduction universally show high levels of variability, and often positive skewness among individuals. This is often interpreted as evidence of heterogeneity, and thus of an opportunity for natural selection. However, variability provides evidence of heterogeneity only if it exceeds the level of variability to be expected in a cohort of identical individuals all experiencing the same vital rates. Such comparisons require a way to calculate the statistics of lifetime reproduction from demographic data. Here, a new approach is presented, using the theory of Markov chains with rewards, obtaining all the moments of the distribution of lifetime reproduction. The approach applies to age- or stage-classified models, to constant, periodic, or stochastic environments, and to any kind of reproductive schedule. As examples, I analyze data from six empirical studies, of a variety of animal and plant taxa (nematodes, polychaetes, humans, and several species of perennial plants.

  17. COST MODEL FOR LARGE URBAN SCHOOLS.

    Science.gov (United States)

    O'BRIEN, RICHARD J.

    THIS DOCUMENT CONTAINS A COST SUBMODEL OF AN URBAN EDUCATIONAL SYSTEM. THIS MODEL REQUIRES THAT PUPIL POPULATION AND PROPOSED SCHOOL BUILDING ARE KNOWN. THE COST ELEMENTS ARE--(1) CONSTRUCTION COSTS OF NEW PLANTS, (2) ACQUISITION AND DEVELOPMENT COSTS OF BUILDING SITES, (3) CURRENT OPERATING EXPENSES OF THE PROPOSED SCHOOL, (4) PUPIL…

  18. Lifetime measurements in 71Ge and a new interacting boson-fermion model interpretation

    Science.gov (United States)

    Ivaşcu, M.; Mărginean, N.; Bucurescu, D.; Căta-Danil, I.; Ur, C. A.; Lobach, Yu. N.

    1999-08-01

    The lifetimes of twelve low spin excited states have been measured in 71Ge using the Doppler shift attenuation method in the 71Ga(p,nγ) reaction at 3.0 and 3.5 MeV incident energy. New interacting boson-fermion model calculations for this nucleus account well for the properties of all its levels known up to about 1.5 MeV excitation.

  19. Statistical Methods for Detecting and Modeling General Patterns and Relationships in Lifetime Data

    Energy Technology Data Exchange (ETDEWEB)

    Kvaloey, Jan Terje

    1999-04-01

    In this thesis, the author tries to develop methods of detecting and modeling general patterns and relationships in lifetime data. Tests with power against nonmonotonic trends and nonmonotonic co variate effects are considered, and nonparametric regression methods which allow estimation of fairly general nonlinear relationships are studied. Practical uses of some of the methods are illustrated although in a medical rather than engineering or technological context.

  20. Evaluation of observed and modelled aerosol lifetimes using radioactive tracers of opportunity and an ensemble of 19 global models

    Science.gov (United States)

    Kristiansen, N. I.; Stohl, A.; Olivié, D. J. L.; Croft, B.; Søvde, O. A.; Klein, H.; Christoudias, T.; Kunkel, D.; Leadbetter, S. J.; Lee, Y. H.; Zhang, K.; Tsigaridis, K.; Bergman, T.; Evangeliou, N.; Wang, H.; Ma, P.-L.; Easter, R. C.; Rasch, P. J.; Liu, X.; Pitari, G.; Di Genova, G.; Zhao, S. Y.; Balkanski, Y.; Bauer, S. E.; Faluvegi, G. S.; Kokkola, H.; Martin, R. V.; Pierce, J. R.; Schulz, M.; Shindell, D.; Tost, H.; Zhang, H.

    2016-03-01

    Aerosols have important impacts on air quality and climate, but the processes affecting their removal from the atmosphere are not fully understood and are poorly constrained by observations. This makes modelled aerosol lifetimes uncertain. In this study, we make use of an observational constraint on aerosol lifetimes provided by radionuclide measurements and investigate the causes of differences within a set of global models. During the Fukushima Dai-Ichi nuclear power plant accident of March 2011, the radioactive isotopes cesium-137 (137Cs) and xenon-133 (133Xe) were released in large quantities. Cesium attached to particles in the ambient air, approximately according to their available aerosol surface area. 137Cs size distribution measurements taken close to the power plant suggested that accumulation-mode (AM) sulfate aerosols were the main carriers of cesium. Hence, 137Cs can be used as a proxy tracer for the AM sulfate aerosol's fate in the atmosphere. In contrast, the noble gas 133Xe behaves almost like a passive transport tracer. Global surface measurements of the two radioactive isotopes taken over several months after the release allow the derivation of a lifetime of the carrier aerosol. We compare this to the lifetimes simulated by 19 different atmospheric transport models initialized with identical emissions of 137Cs that were assigned to an aerosol tracer with each model's default properties of AM sulfate, and 133Xe emissions that were assigned to a passive tracer. We investigate to what extent the modelled sulfate tracer can reproduce the measurements, especially with respect to the observed loss of aerosol mass with time. Modelled 137Cs and 133Xe concentrations sampled at the same location and times as station measurements allow a direct comparison between measured and modelled aerosol lifetime. The e-folding lifetime τe, calculated from station measurement data taken between 2 and 9 weeks after the start of the emissions, is 14.3 days (95

  1. Evaluation of observed and modelled aerosol lifetimes using radioactive tracers of opportunity and an ensemble of 19 global models

    Directory of Open Access Journals (Sweden)

    N. I. Kristiansen

    2015-09-01

    Full Text Available Aerosols have important impacts on air quality and climate, but the processes affecting their removal from the atmosphere are not fully understood and are poorly constrained by observations. This makes modelled aerosol lifetimes uncertain. In this study, we make use of an observational constraint on aerosol lifetimes provided by radionuclide measurements and investigate the causes of differences within a set of global models. During the Fukushima Dai-Ichi nuclear power plant accident of March 2011, the radioactive isotopes cesium-137 (137Cs and xenon-133 (133Xe were released in large quantities. Cesium attached to particles in the ambient air, approximately according to their available aerosol surface area. 137Cs size distribution measurements taken close to the power plant suggested that accumulation-mode (AM sulphate aerosols were the main carriers for the cesium. Hence, 137Cs can be used as a proxy tracer for the AM sulphate aerosol's fate in the atmosphere. In contrast, the noble gas 133Xe behaves almost like a passive transport tracer. Global surface measurements of the two radioactive isotopes taken over several months after the release allow the derivation of a lifetime of the carrier aerosol. We compare this to the lifetimes simulated by 19 different atmospheric transport models initialized with identical emissions of 137Cs that were assigned to an aerosol tracer with each model's default properties of AM sulphate, and 133Xe emissions that were assigned to a passive tracer. We investigate to what extent the modelled sulphate tracer can reproduce the measurements, especially with respect to the observed loss of aerosol mass with time. Modelled 37Cs and 133Xe concentrations sampled at the same location and times as station measurements allow a direct comparison between measured and modelled aerosol lifetime. The e-folding lifetime τe, calculated from station measurement data taken between two and nine weeks after the start of the

  2. Stochastic modeling and survival analysis of marginally trapped neutrons for a magnetic trapping neutron lifetime experiment

    CERN Document Server

    Coakley, K J; M.,; Huber, G; P.,; Huffman, R; C.,; Huffer, R; Marley, D E; Mumm, H P; O'Shaughnessy, M; K.,; Schelhammer, W; Thompson, A K; Yue, A T

    2015-01-01

    In a variety of neutron lifetime experiments, in addition to $\\beta-$decay, neutrons can be lost by other mechanisms including wall losses. Failure to account for these other loss mechanisms produces systematic measurement error and associated systematic uncertainties in neutron lifetime measurements. In this work, we develop a physical model for neutron wall losses and construct a competing risks survival analysis model to account for losses due to the joint effect of $\\beta-$decay losses, wall losses of marginally trapped neutrons, and an additional absorption mechanism. We determine the survival probability function associated with the wall loss mechanism by a Monte Carlo method. Based on a fit of the competing risks model to a subset of the NIST experimental data, we determine the mean lifetime of trapped neutrons to be approximately 700 s -- considerably less than the current best estimate of (880.1 $\\pm$ 1.1) s promulgated by the Particle Data Group [1]. Currently, experimental studies are underway to d...

  3. A new lifetime estimation model for a quicker LED reliability prediction

    Science.gov (United States)

    Hamon, B. H.; Mendizabal, L.; Feuillet, G.; Gasse, A.; Bataillou, B.

    2014-09-01

    LED reliability and lifetime prediction is a key point for Solid State Lighting adoption. For this purpose, one hundred and fifty LEDs have been aged for a reliability analysis. LEDs have been grouped following nine current-temperature stress conditions. Stress driving current was fixed between 350mA and 1A and ambient temperature between 85C and 120°C. Using integrating sphere and I(V) measurements, a cross study of the evolution of electrical and optical characteristics has been done. Results show two main failure mechanisms regarding lumen maintenance. The first one is the typically observed lumen depreciation and the second one is a much more quicker depreciation related to an increase of the leakage and non radiative currents. Models of the typical lumen depreciation and leakage resistance depreciation have been made using electrical and optical measurements during the aging tests. The combination of those models allows a new method toward a quicker LED lifetime prediction. These two models have been used for lifetime predictions for LEDs.

  4. Cost Models: A Study in Persuasion

    Science.gov (United States)

    Fauley, Franz E.

    1975-01-01

    The article defines the major elements (fundamental questions, basic assumptions, anticipated costs, projected savings, and return on investment) of a cost model, discusses the function and importance of each of these elements, and illustrates the development and construction of a cost model through an analysis of a hypothetical speed reading…

  5. Study of behavior and determination of customer lifetime value(CLV) using Markov chain model

    Science.gov (United States)

    Permana, Dony; Indratno, Sapto Wahyu; Pasaribu, Udjianna S.

    2014-03-01

    Customer Lifetime Value or CLV is a restriction on interactive marketing to help a company in arranging financial for the marketing of new customer acquisition and customer retention. Additionally CLV can be able to segment customers for financial arrangements. Stochastic models for the fairly new CLV used a Markov chain. In this model customer retention probability and new customer acquisition probability play an important role. This model is originally introduced by Pfeifer and Carraway in 2000 [1]. They introduced several CLV models, one of them only involves customer and former customer. In this paper we expand the model by adding the assumption of the transition from former customer to customer. In the proposed model, the CLV value is higher than the CLV value obtained by Pfeifer and Caraway model. But our model still requires a longer convergence time.

  6. Validation of a regression model for standardizing lifetime racing performances of thoroughbreds.

    Science.gov (United States)

    Martin, G S; Strand, E; Kearney, M T

    1997-06-01

    To determine the relationship between prediction errors of a regression model of racing finish times and earnings or finish position; the relationship between standardized finish times, determined by use of this model, and earnings or finish position; and whether this model was valid when applied to data for horses that underwent surgical treatment. Survey. Records of 6,700 healthy Thoroughbreds racing in Louisiana and of 31 Thoroughbreds with idiopathic left laryngeal hemiplegia that underwent surgical treatment. Predicted and standardized finish times were calculated by use of the regression model for healthy horses, and the relationships between prediction error (actual--predicted finish time) and standardized finish times, and earnings and finish position, were examined. Then, the regression model was applied to data for horses with hemiplegia to determine whether the model was valid when used to calculate predicted and standardized finish times for lifetime performance data. Prediction error and standardized finish times were negatively correlated with earnings and positively correlated with finish position and, thus, appeared to be reliable measures of racing performance. The regression model was found to be valid when applied to lifetime performance records of horses with laryngeal hemiplegia. Prediction error and standardized finish times are measures of racing performance that can be used to compare performances among Thoroughbred racehorses across a variety of circumstances that would otherwise confound comparison.

  7. Fluorescence lifetime imaging of endogenous molecules in live mouse cancer models (Conference Presentation)

    Science.gov (United States)

    Svindrych, Zdenek; Wang, Tianxiong; Hu, Song; Periasamy, Ammasi

    2017-02-01

    NADH and FAD are important endogenous fluorescent coenzymes participating in key enzymatic reactions of cellular metabolism. While fluorescence intensities of NADH and FAD have been used to determine the redox state of cells and tissues, this simple approach breaks down in the case of deep-tissue intravital imaging due to depth- and wavelength-dependent light absorption and scattering. To circumvent this limitation, our research focuses on fluorescence lifetimes of two-photon excited NADH and FAD emission to study the metabolic state of live tissues. In our custom-built scanning microscope we combine tunable femtosecond Ti:sapphire laser (operating at 740 nm for NADH excitation and 890 nm for FAD excitation), two GaAsP hybrid detectors for registering individual fluorescence photons and two Becker and Hickl time correlator boards for high precision lifetime measurements. Together with our rigorous FLIM analysis approach (including image segmentation, multi-exponential decay fitting and detailed statistical analysis) we are able to detect metabolic changes in cancer xenografts (human pancreatic cancer MPanc96 cells injected subcutaneously into the ear of an immunodeficient nude mouse), relative to surrounding healthy tissue. Advantageously, with the same instrumentation we can also take high-resolution and high-contrast images of second harmonic signal (SHG) originating from collagen fibers of both the healthy skin and the growing tumor. The combination of metabolic measurements (NADH and FAD lifetime) and morphological information (collagen SHG) allows us to follow the tumor growth in live mouse model and the changes in tumor microenvironment.

  8. Analysis and modeling of rail maintenance costs

    Directory of Open Access Journals (Sweden)

    Amir Ali Bakhshi

    2012-01-01

    Full Text Available Railroad maintenance engineering plays an important role on availability of roads and reducing the cost of railroad incidents. Rail is of the most important parts of railroad industry, which needs regular maintenance since it covers a significant part of total maintenance cost. Any attempt on optimizing total cost of maintenance could substantially reduce the cost of railroad system and it can reduce total cost of the industry. The paper presents a new method to estimate the cost of rail failure using different cost components such as cost of inspection and cost of risk associated with possible accidents. The proposed model of this paper is used for a real-world case study of railroad transportation of Tehran region and the results have been analyzed.

  9. Modelling the Costs of Preserving Digital Assets

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2012-01-01

    on experiences from a Danish project to develop a cost model. It was found that a generic cost model should account for the nature of the organisation and the assets to be preserved, and for all major preservation activities and cost drivers. In addition, it should describe accounting principles. It was proposed......Information is increasingly being produced in digital form, and some of it must be preserved for the longterm. Digital preservation includes a series of actively managed activities that require on-going funding. To obtain sufficient resources, there is a need for assessing the costs...... and the benefits accrued by preserving the assets. Cost data is also needed for optimizing activities and comparing the costs of different preservation alternatives. The purpose of this study is to analyse generic requirements for modelling the cost of preserving digital assets. The analysis was based...

  10. Modelling the Costs of Preserving Digital Assets

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2012-01-01

    and the benefits accrued by preserving the assets. Cost data is also needed for optimizing activities and comparing the costs of different preservation alternatives. The purpose of this study is to analyse generic requirements for modelling the cost of preserving digital assets. The analysis was based......Information is increasingly being produced in digital form, and some of it must be preserved for the longterm. Digital preservation includes a series of actively managed activities that require on-going funding. To obtain sufficient resources, there is a need for assessing the costs...... on experiences from a Danish project to develop a cost model. It was found that a generic cost model should account for the nature of the organisation and the assets to be preserved, and for all major preservation activities and cost drivers. In addition, it should describe accounting principles. It was proposed...

  11. Cost Concept Model and Gateway Specification

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad

    2014-01-01

    to promote interoperability; • A Nested Model for Digital Curation—that visualises the core concepts, demonstrates how they interact and places them into context visually by linking them to A Cost and Benefit Model for Curation; This Framework provides guidance for data collection and associated calculations......This document introduces a Framework supporting the implementation of a cost concept model against which current and future cost models for curating digital assets can be benchmarked. The value built into this cost concept model leverages the comprehensive engagement by the 4C project with various...... user communities and builds upon our understanding of the requirements, drivers, obstacles and objectives that various stakeholder groups have relating to digital curation. Ultimately, this concept model should provide a critical input to the development and refinement of cost models as well as helping...

  12. Bayesian framework for parametric bivariate accelerated lifetime modeling and its application to hospital acquired infections.

    Science.gov (United States)

    Bilgili, D; Ryu, D; Ergönül, Ö; Ebrahimi, N

    2016-03-01

    Infectious diseases that can be spread directly or indirectly from one person to another are caused by pathogenic microorganisms such as bacteria, viruses, parasites, or fungi. Infectious diseases remain one of the greatest threats to human health and the analysis of infectious disease data is among the most important application of statistics. In this article, we develop Bayesian methodology using parametric bivariate accelerated lifetime model to study dependency between the colonization and infection times for Acinetobacter baumannii bacteria which is leading cause of infection among the hospital infection agents. We also study their associations with covariates such as age, gender, apache score, antibiotics use 3 months before admission and invasive mechanical ventilation use. To account for singularity, we use Singular Bivariate Extreme Value distribution to model residuals in Bivariate Accelerated lifetime model under the fully Bayesian framework. We analyze a censored data related to the colonization and infection collected in five major hospitals in Turkey using our methodology. The data analysis done in this article is for illustration of our proposed method and can be applied to any situation that our model can be used.

  13. HTGR Cost Model Users' Manual

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Gandrik

    2012-01-01

    The High Temperature Gas-Cooler Reactor (HTGR) Cost Model was developed at the Idaho National Laboratory for the Next Generation Nuclear Plant Project. The HTGR Cost Model calculates an estimate of the capital costs, annual operating and maintenance costs, and decommissioning costs for a high-temperature gas-cooled reactor. The user can generate these costs for multiple reactor outlet temperatures; with and without power cycles, including either a Brayton or Rankine cycle; for the demonstration plant, first of a kind, or nth of a kind project phases; for a single or four-pack configuration; and for a reactor size of 350 or 600 MWt. This users manual contains the mathematical models and operating instructions for the HTGR Cost Model. Instructions, screenshots, and examples are provided to guide the user through the HTGR Cost Model. This model was design for users who are familiar with the HTGR design and Excel. Modification of the HTGR Cost Model should only be performed by users familiar with Excel and Visual Basic.

  14. Cost Modeling for SOC Modules Testing

    Directory of Open Access Journals (Sweden)

    Balwinder Singh

    2013-08-01

    Full Text Available The complexity of the system design is increasing very rapidly as the number of transistors on Integrated Circuits (IC doubles as per Moore’s law.There is big challenge of testing this complex VLSI circuit, in which whole system is integrated into a single chip called System on Chip (SOC. Cost of testing the SOC is also increasing with complexity. Cost modeling plays a vital role in reduction of test cost and time to market. This paper includes the cost modeling of the SOC Module testing which contains both analog and digital modules. The various test cost parameters and equations are considered from the previous work. The mathematical relations are developed for cost modeling to test the SOC further cost modeling equations are modeled in Graphical User Interface (GUI in MATLAB, which can be used as a cost estimation tool. A case study is done to calculate the cost of the SOC testing due to Logic Built in Self Test (LBIST and Memory Built in Self Test (MBIST. VLSI Test engineers can take the benefits of such cost estimation tools for test planning.

  15. Modelling total energy costs of sports centres

    Energy Technology Data Exchange (ETDEWEB)

    Boussabaine, A.H.; Kirkham, R.J.; Grew, R.J. [Liverpool Univ., School of Architecture and Building Engineering, Liverpool (United Kingdom)

    1999-12-07

    Providing and maintaining safe and comfortable conditions in sport centres raises many issues, particularly cost. The paper gives an overview of the factors associated with sport centre servicing and attempts to highlight the governing factors associated with this, particularly energy costs. A total of 19 sport centres in the City of Liverpool in the UK are investigated, using data elicited from the Liverpool Leisure Services Directorate. The energy operating costs were analysed using statistical methods. Six models were developed to predict total energy costs. Testing and validation results showed a high level of model accuracy. The models would be of use to professionals involved in feasibility studies at the design stage. (Author)

  16. EOQ Models with Varying Holding Cost

    Directory of Open Access Journals (Sweden)

    Naser Ghasemi

    2013-01-01

    Full Text Available Models of inventory management contain different parameters. An issue is observable in the classical models which can be related to the determination of the quantity of the economic order and the quantity of the economic production. In these models, the parameters like setup and holding costs and also the rate of demands are fixed. This matter causes the quantity of the economic ordering in classic model to have some differences in comparison with the real-world conditions. It should be stated that holding cost of spoiled and useless products is not always fixed and so the costs increase by passing the time. This paper is an attempt to develop classical EOQ models by considering holding cost as an increasing function of the ordering cycle length. So the classical EOQ models are developed, and the related optimum quantity to the ordering cycle length, economic ordering quantity, and the optimum total cost are determined.

  17. Cost Concept Model and Gateway Specification

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad

    2014-01-01

    This document introduces a Framework supporting the implementation of a cost concept model against which current and future cost models for curating digital assets can be benchmarked. The value built into this cost concept model leverages the comprehensive engagement by the 4C project with various...... to ensure that the curation and preservation solutions and services that will inevitably arise from the commercial sector as ‘supply’ respond to a much better understood ‘demand’ for cost-effective and relevant tools. To meet acknowledged gaps in current provision, a nested model of curation which addresses...... user communities and builds upon our understanding of the requirements, drivers, obstacles and objectives that various stakeholder groups have relating to digital curation. Ultimately, this concept model should provide a critical input to the development and refinement of cost models as well as helping...

  18. Bayesian Network Model with Application to Smart Power Semiconductor Lifetime Data.

    Science.gov (United States)

    Plankensteiner, Kathrin; Bluder, Olivia; Pilz, Jürgen

    2015-09-01

    In this article, Bayesian networks are used to model semiconductor lifetime data obtained from a cyclic stress test system. The data of interest are a mixture of log-normal distributions, representing two dominant physical failure mechanisms. Moreover, the data can be censored due to limited test resources. For a better understanding of the complex lifetime behavior, interactions between test settings, geometric designs, material properties, and physical parameters of the semiconductor device are modeled by a Bayesian network. Statistical toolboxes in MATLAB® have been extended and applied to find the best structure of the Bayesian network and to perform parameter learning. Due to censored observations Markov chain Monte Carlo (MCMC) simulations are employed to determine the posterior distributions. For model selection the automatic relevance determination (ARD) algorithm and goodness-of-fit criteria such as marginal likelihoods, Bayes factors, posterior predictive density distributions, and sum of squared errors of prediction (SSEP) are applied and evaluated. The results indicate that the application of Bayesian networks to semiconductor reliability provides useful information about the interactions between the significant covariates and serves as a reliable alternative to currently applied methods.

  19. The perpetual student: modeling duration of undergraduate studies based on lifetime-type educational data.

    Science.gov (United States)

    Kalamatianou, Aglaia G; McClean, Sally

    2003-12-01

    It is important to educational planners to estimate the likelihood and time-scale of graduation of students enrolled on a curriculum. The particular case we are concerned with, emerges when studies are not completed in the prescribed interval of time. Under these circumstances we use a framework of survival analysis applied to lifetime-type educational data to examine the distribution of duration of undergraduate studies for 10,313 students, enrolled in a Greek university during ten consecutive academic years. Non-parametric and parametric survival models have been developed for handling this distribution as well as a modified procedure for testing goodness-of-fit of the models. Data censoring was taken into account in the statistical analysis and the problems of thresholding of graduation and of perpetual students are also addressed. We found that the proposed parametric model adequately describes the empirical distribution provided by non-parametric estimation. We also found significant difference between duration of studies of men and women students. The proposed methodology could be useful to analyse data from any other type and level of education or general lifetime data with similar characteristics.

  20. Modeling of LaB6 hollow cathode performance and lifetime

    Science.gov (United States)

    Pedrini, Daniela; Albertoni, Riccardo; Paganucci, Fabrizio; Andrenucci, Mariano

    2015-01-01

    Thermionic hollow cathodes are currently used as sources of electrons in a variety of space applications, in particular as cathodes/neutralizers of electric thrusters (Hall effect and ion thrusters). Numerical tools are needed to guide the design of new devices before their manufacturing and testing, since multiple geometrical parameters influence the cathode performance. A reduced-order, numerical model was developed to assess the performance of orificed hollow cathodes, with a focus on the operational lifetime. The importance of the lifetime prediction is tied to its impact on the operational lifetime of the thruster to which the cathode is coupled. The cathode architecture consists of a refractory metal tube with an internal electron emitter made of lanthanum hexaboride (LaB6). The choice of LaB6 accounts for the reduced evaporation rate, the low sensitivity to poisoning and the absence of an activation procedure with respect to oxide cathodes. A LaB6 emitter is thus a valuable option for long-lasting cathodes, despite its relatively high work-function and reactivity with many refractory metals at high temperatures. The suggested reduced-order model self-consistently predicts the key parameters of the cathode operation, shedding light on the power deposition processes as well as on the main erosion mechanisms. Preliminary results showed good agreement with both the experimental data collected by Alta and data available from the literature for different operating conditions and power levels. Next developments will include further comparisons between theoretical and experimental data, considering cathodes of various size and operating conditions.

  1. Model adjointization and its cost

    Institute of Scientific and Technical Information of China (English)

    CHENG Qiang; ZHANG Linbo; WANG Bin

    2004-01-01

    In this article, the least program behavior decomposition method (LPBD) is put forward from a program structure point of view. This method can be extensively used both in algorithms of automatic differentiation (AD) and in tools design, and does not require programs to be evenly separable but the cost in terms of operations count and memory is similar to methods using checkpointing. This article starts by summarizing the rules of adjointization and then presents the implementation of LPBD. Next, the definition of the separable program space, based on the fundamental assumptions (FA) of automatic differentiation, is given and the differentiation cost functions are derived. Also,two constants of fundamental importance in AD, σ and μ, are derived under FA. Under the assumption of even separability, the adjoint cost of simple and deep decomposition is subsequently discussed quantitatively using checkpointing. Finally, the adjoint costs in terms of operations count and memory through the LPBD method are shown to be uniformly dependent on the depth of structure or decomposition.

  2. An economic model of cost effectiveness of peer interventions to prevent HIV infections in prison.

    OpenAIRE

    Roberta Longo; Claire Hulme; Armando Vargas-Palacios; Karen Vinall-Collier; Jane South; Anne Marie Bagnall; James Woodall; Gary Raine; Karina Kinsella

    2014-01-01

    Aim: To assess the cost-effectiveness of peer-based sexual behaviour education interventions in prison settings to prevent primary and secondary HIV infections. Methods: Based on the results of a systematic review of peer-based interventions in prison settings, we developed a Bernoulli model to estimate the number of HIV infections averted, consequent loss of quality-adjusted life years (QALYs) avoided and associated savings in health care costs over a lifetime respectively for a peer-led and...

  3. Cost Models for MMC Manufacturing Processes

    Science.gov (United States)

    Elzey, Dana M.; Wadley, Haydn N. G.

    1996-01-01

    Processes for the manufacture of advanced metal matrix composites are rapidly approaching maturity in the research laboratory and there is growing interest in their transition to industrial production. However, research conducted to date has almost exclusively focused on overcoming the technical barriers to producing high-quality material and little attention has been given to the economical feasibility of these laboratory approaches and process cost issues. A quantitative cost modeling (QCM) approach was developed to address these issues. QCM are cost analysis tools based on predictive process models relating process conditions to the attributes of the final product. An important attribute, of the QCM approach is the ability to predict the sensitivity of material production costs to product quality and to quantitatively explore trade-offs between cost and quality. Applications of the cost models allow more efficient direction of future MMC process technology development and a more accurate assessment of MMC market potential. Cost models were developed for two state-of-the art metal matrix composite (MMC) manufacturing processes: tape casting and plasma spray deposition. Quality and Cost models are presented for both processes and the resulting predicted quality-cost curves are presented and discussed.

  4. BELA receiver performance modeling over the BepiColombo mission lifetime

    Science.gov (United States)

    Gunderson, Kurt; Thomas, Nicolas

    2010-01-01

    Performance modeling of the BepiColombo laser altimeter (BELA) receiver has been performed in the context of return pulse detection probability and measurement accuracies. Models have been extended beyond earlier work [Gunderson, K., Thomas, N., Rohner, M., 2006. A laser altimeter performance model and its application to BELA. IEEE Transactions on Geoscience and Remote Sensing 44, 3308-3319] to explore the receiver response to time-varying orbital conditions and potential instrument component degradations over the mission lifetime. New signal processing derivations are presented, and the set of measurement accuracy predictions has been broadened to include albedo and return pulse width in addition to range accuracy. Two detector gain optimization derivations are also described and applied as guides towards the identification of a preferred performance enhancing strategy.

  5. Cost Modeling for SOC Modules Testing

    OpenAIRE

    Balwinder Singh; Arun Khosla; Sukhleen B. Narang

    2013-01-01

    The complexity of the system design is increasing very rapidly as the number of transistors on Integrated Circuits (IC) doubles as per Moore’s law.There is big challenge of testing this complex VLSI circuit, in which whole system is integrated into a single chip called System on Chip (SOC). Cost of testing the SOC is also increasing with complexity. Cost modeling plays a vital role in reduction of test cost and time to market. This paper includes the cost modeling of the SOC Module testing...

  6. Lifetime modelling for MCrAlY coatings in industrial gas turbine blades

    Directory of Open Access Journals (Sweden)

    Krukovsky Pavel

    2004-01-01

    Full Text Available A novel theoretical and experimental approach for lifetime modelling of MCrAlY coatings for stationary gas turbines has been undertaken using the Inverse Problem Solution (IPS technique. With this technique feasible experimental data acquired after a defined experimental time t e are used as input values for the model parameters estimation. In the first stage of the approach a model, based on the oxidation and diffusion processes (Fick's first and second law was assumed, which considers the Al concentration profile across the coating. The measured average Al concentration profiles in the two-phase g+b and g - regions of coating as well as base metal were used as input values for the model parameters estimation and calculational prediction of the long term diffusion and oxidation behavior of the coating was performed. The time, when the b-NiAl phase is completely consumed was assumed as the coating lifetime end. Exposure experiments were carried out with a NiCoCrAlY coating (200 micron thickness with 8% Al in air at 900 °C and 950 °C, currently up to 10000 h. The oxide scale is growing continuously and no other oxides were observed. The average and b-NiAl phase concentration profiles of Al across the coating thickness were determined by electron microprobe and image analysis systems in the initial state after 700 and 10000 h of oxidation. The concentration profile measured after 700 h was used as input values for the model parameters estimation in order to calculate the Al and b-NiAl phase concentration profiles after 10000 h. The computational forecast for 10000 h at 950 °C and 900 °C are in good agreement with the measured data. The approach was applied for NiCoCrAlY (200 micron thickness coating lifetime modelling at 950 °C and 900 °C as well as for different coating thicknesses at 950 °C.

  7. Plural Governance: A Modified Transaction Cost Model

    DEFF Research Database (Denmark)

    Mols, Niels Peter; Menard, Claude

    2014-01-01

    a model relating transaction cost and resource-based variables to the cost of the plural form. The model is then used to analyze when the plural form is efficient compared to alternative governance structures. We also use the model to discuss the strength of three plural form synergies.......Plural governance is a form of governance where a firm both makes and buys similar goods or services. Despite a widespread use of plural governance there are no transaction cost models of how plural governance affects performance. This paper reviews the literature about plural forms and proposes...

  8. Quasars Are Not Light-Bulbs: Testing Models of Quasar Lifetimes with the Observed Eddington Ratio Distribution

    CERN Document Server

    Hopkins, Philip F

    2008-01-01

    We use the observed distribution of Eddington ratios as a function of supermassive black hole (BH) mass to constrain models of AGN lifetimes and lightcurves. Given the observed AGN luminosity function, a model for AGN lifetimes (time above a given luminosity) translates directly to a predicted Eddington ratio distribution. Models for self-regulated BH growth, in which feedback produces a 'blowout' decay phase after some peak luminosity (shutting down accretion) make specific predictions for the lifetimes distinct from those expected if AGN are simply gas starved (without feedback) and very different from simple phenomenological 'light bulb' models. Present observations of the Eddington ratio distribution, spanning 5 decades in Eddington ratio, 3 in BH mass, and redshifts z=0-1, agree with the predictions of self-regulated models, and rule out 'light-bulb', pure exponential, and gas starvation models at high significance. We compare the Eddington ratio distributions at fixed BH mass and fixed luminosity (both ...

  9. Improving Trust and Reputation Modeling in E-Commerce Using Agent Lifetime and Transaction Count

    Science.gov (United States)

    Cormier, Catherine; Tran, Thomas T.

    Effective and reliable trust and reputation modeling systems are central to the success of decentralized e-commerce systems where autonomous agents are relied upon to conduct commercial transactions. However, the subjective and social-based qualities that are inherent to trust and reputation introduce many complexities into the development of a reliable model. Existing research has successfully demonstrated how trust systems can be decentralized and has illustrated the importance of sharing trust information, or rather, modeling reputation. Still, few models have provided a solution for developing an initial set of advisors from whom to solicit reputation rankings, or have taken into account all of the social criteria used to determine trustworthiness. To meet these objectives, we propose the use of two new parameters in trust and reputation modeling: agent lifetime and total transaction count. We describe a model that employs these parameters to calculate an agent’s seniority, then apply this information when selecting agents for soliciting and ranking reputation information. Experiments using this model are described. The results are then presented and discussed to evaluate the effect of using these parameters in reputation modeling. We also discuss the value of our particular model in contrast with related work and conclude with directions for future research.

  10. Trends in lifetime risk and years of life lost due to diabetes in the USA, 1985-2011: a modelling study.

    Science.gov (United States)

    Gregg, Edward W; Zhuo, Xiaohui; Cheng, Yiling J; Albright, Ann L; Narayan, K M Venkat; Thompson, Theodore J

    2014-11-01

    Diabetes incidence has increased and mortality has decreased greatly in the USA, potentially leading to substantial changes in the lifetime risk of diabetes. We aimed to provide updated estimates for the lifetime risk of development of diabetes and to assess the effect of changes in incidence and mortality on lifetime risk and life-years lost to diabetes in the USA. We incorporated data about diabetes incidence from the National Health Interview Survey, and linked data about mortality from 1985 to 2011 for 598 216 adults, into a Markov chain model to estimate remaining lifetime diabetes risk, years spent with and without diagnosed diabetes, and life-years lost due to diabetes in three cohorts: 1985-89, 1990-99, and 2000-11. Diabetes was determined by self-report and was classified as any diabetes, excluding gestational diabetes. We used logistic regression to estimate the incidence of diabetes and Poisson regression to estimate mortality. On the basis of 2000-11 data, lifetime risk of diagnosed diabetes from age 20 years was 40·2% (95% CI 39·2-41·3) for men and 39·6% (38·6-40·5) for women, representing increases of 20 percentage points and 13 percentage points, respectively, since 1985-89. The highest lifetime risks were in Hispanic men and women, and non-Hispanic black women, for whom lifetime risk now exceeds 50%. The number of life-years lost to diabetes when diagnosed at age 40 years decreased from 7·7 years (95% CI 6·5-9·0) in 1990-99 to 5·8 years (4·6-7·1) in 2000-11 in men, and from 8·7 years (8·4-8·9) to 6·8 years (6·7-7·0) in women over the same period. Because of the increasing diabetes prevalence, the average number of years lost due to diabetes for the population as a whole increased by 46% in men and 44% in women. Years spent with diabetes increased by 156% in men and 70% in women. Continued increases in the incidence of diagnosed diabetes combined with declining mortality have led to an acceleration of lifetime risk and more years

  11. Modeling motivation and habit in driving behavior under lifetime driver's license revocation.

    Science.gov (United States)

    Tseng, Chien-Ming; Chang, Hsin-Li; Woo, T Hugh

    2013-03-01

    The purpose of the present study was to verify the motivational factors underlying the theory of planned behavior (TPB) predicting the driving behavior of lifetime driving license revoked offenders. Of a total of 639 drivers whose licenses had been permanently revoked, 544 offenders completed a questionnaire constructed to measure attitudes toward behaviors, subjective norms, perceived behavioral control, behavioral intentions (the key constructs of the TPB), and previous driving habit strength. The finding of the study revealed that an offenders' driving behavior after a lifetime license revocation was significantly correlated to behavioral intention (R=0.60, p<0.01), perceived behavioral control (R=0.61, p<0.01), previous driving habit (R=0.44, p<0.01), and attitude (R=0.41, p<0.01). There was no evidence that subjective norms including road regulation, society ethics, and people important to offenders had an influence on driving behavior (R=0.03). Low driving habit strength offenders are motivated to drive because of behavioral intention, whereas strong driving habit strength offenders are motivated to drive because of perceived behavioral control. Previous driving habit strength is a moderator in the intention-behavior relationship. The model appeared successful when previous habits were weak, but less successful when previous habits were strong.

  12. Development of a lifetime prediction model for lithium-ion batteries based on extended accelerated aging test data

    Science.gov (United States)

    Ecker, Madeleine; Gerschler, Jochen B.; Vogel, Jan; Käbitz, Stefan; Hust, Friedrich; Dechent, Philipp; Sauer, Dirk Uwe

    2012-10-01

    Battery lifetime prognosis is a key requirement for successful market introduction of electric and hybrid vehicles. This work aims at the development of a lifetime prediction approach based on an aging model for lithium-ion batteries. A multivariable analysis of a detailed series of accelerated lifetime experiments representing typical operating conditions in hybrid electric vehicle is presented. The impact of temperature and state of charge on impedance rise and capacity loss is quantified. The investigations are based on a high-power NMC/graphite lithium-ion battery with good cycle lifetime. The resulting mathematical functions are physically motivated by the occurring aging effects and are used for the parameterization of a semi-empirical aging model. An impedance-based electric-thermal model is coupled to the aging model to simulate the dynamic interaction between aging of the battery and the thermal as well as electric behavior. Based on these models different drive cycles and management strategies can be analyzed with regard to their impact on lifetime. It is an important tool for vehicle designers and for the implementation of business models. A key contribution of the paper is the parameterization of the aging model by experimental data, while aging simulation in the literature usually lacks a robust empirical foundation.

  13. Modeling of high homologous temperature deformation behavior for stress and life-time analyses

    Energy Technology Data Exchange (ETDEWEB)

    Krempl, E. [Rensselaer Polytechnic Institute, Troy, NY (United States)

    1997-12-31

    Stress and lifetime analyses need realistic and accurate constitutive models for the inelastic deformation behavior of engineering alloys at low and high temperatures. Conventional creep and plasticity models have fundamental difficulties in reproducing high homologous temperature behavior. To improve the modeling capabilities {open_quotes}unified{close_quotes} state variable theories were conceived. They consider all inelastic deformation rate-dependent and do not have separate repositories for creep and plasticity. The viscoplasticity theory based on overstress (VBO), one of the unified theories, is introduced and its properties are delineated. At high homologous temperature where secondary and tertiary creep are observed modeling is primarily accomplished by a static recovery term and a softening isotropic stress. At low temperatures creep is merely a manifestation of rate dependence. The primary creep modeled at low homologous temperature is due to the rate dependence of the flow law. The model is unaltered in the transition from low to high temperature except that the softening of the isotropic stress and the influence of the static recovery term increase with an increase of the temperature.

  14. Solving inverse problem for Markov chain model of customer lifetime value using flower pollination algorithm

    Science.gov (United States)

    Al-Ma'shumah, Fathimah; Permana, Dony; Sidarto, Kuntjoro Adji

    2015-12-01

    Customer Lifetime Value is an important and useful concept in marketing. One of its benefits is to help a company for budgeting marketing expenditure for customer acquisition and customer retention. Many mathematical models have been introduced to calculate CLV considering the customer retention/migration classification scheme. A fairly new class of these models which will be described in this paper uses Markov Chain Models (MCM). This class of models has the major advantage for its flexibility to be modified to several different cases/classification schemes. In this model, the probabilities of customer retention and acquisition play an important role. From Pfeifer and Carraway, 2000, the final formula of CLV obtained from MCM usually contains nonlinear form of the transition probability matrix. This nonlinearity makes the inverse problem of CLV difficult to solve. This paper aims to solve this inverse problem, yielding the approximate transition probabilities for the customers, by applying metaheuristic optimization algorithm developed by Yang, 2013, Flower Pollination Algorithm. The major interpretation of obtaining the transition probabilities are to set goals for marketing teams in keeping the relative frequencies of customer acquisition and customer retention.

  15. From Costs to Business Models

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad

    2015-01-01

    . Implementation of our findings would facilitate an organisation’s strategic planning for curation services through an improved understanding of services, streamlining and improvement of those services, planning for new collaborations, and identifying new business opportunities.......This deliverable discusses business models for digital curation. It helps organisations to understand the requirements and drivers for curation services from a supplier and demand side. We investigated existing services and have developed guidelines to address new business opportunities...

  16. Cost Calculation Model for Logistics Service Providers

    Directory of Open Access Journals (Sweden)

    Zoltán Bokor

    2012-11-01

    Full Text Available The exact calculation of logistics costs has become a real challenge in logistics and supply chain management. It is essential to gain reliable and accurate costing information to attain efficient resource allocation within the logistics service provider companies. Traditional costing approaches, however, may not be sufficient to reach this aim in case of complex and heterogeneous logistics service structures. So this paper intends to explore the ways of improving the cost calculation regimes of logistics service providers and show how to adopt the multi-level full cost allocation technique in logistics practice. After determining the methodological framework, a sample cost calculation scheme is developed and tested by using estimated input data. Based on the theoretical findings and the experiences of the pilot project it can be concluded that the improved costing model contributes to making logistics costing more accurate and transparent. Moreover, the relations between costs and performances also become more visible, which enhances the effectiveness of logistics planning and controlling significantly

  17. Application of stochastic models to determine customers lifetime value for a Brazilian supermarkets network

    Directory of Open Access Journals (Sweden)

    Annibal Parracho Sant'Anna

    2008-12-01

    Full Text Available This paper studies strategies to access customer lifetime value (CLV. Traditionally, heuristics based on recency, frequency and monetary value variables (RFM are used to determine the best customers. Here, some forms of directly exploring these parameters to predict CLV are compared to an approach based on fitting a stochastic model. The model employed is a composition of a model for the number of transactions along the residual lifetime and a model for the value spent. New evidence is raised on the effect of aggregating transactions monthly. The data analyzed refer to two years of purchases of a group of customers of the same entrance cohort of a fidelity program cadastre of a supermarkets network in Rio de Janeiro. Using the first year to calibrate and the second year to validate the models, good fit of both models to the series of individual data and coherent CLV predictions are obtained.Este artigo estuda estratégias para avaliar o valor do tempo de vida do cliente (CLV. Tradicionalmente, heurísticas baseadas em variáveis medindo recência, freqüência e valor monetário (RFM são utilizadas para determinar os melhores clientes. Aqui, algumas formas de explorar diretamente estes parâmetros para predizer o CLV são comparadas com uma abordagem baseada no ajustamento de um modelo estocástico. O modelo utilizado é uma composição de um modelo para o número de transações ao longo da vida útil residual e um modelo para o valor gasto. Nova evidência é levantada sobre o efeito de agregação das transações mensalmente. Os dados analisados referem-se a dois anos da compras de um grupo de clientes da mesma coorte de ingresso no cadastro de um programa de fidelidade de uma rede de supermercados do Rio de Janeiro. Usando o primeiro ano para calibrar e o segundo ano para validar os modelos, bom ajuste dos dois modelos para as séries de dados individuais e previsões coerentes para o CLV são obtidas.

  18. Safeguards First Principle Initiative (SFPI) Cost Model

    Energy Technology Data Exchange (ETDEWEB)

    Mary Alice Price

    2010-07-11

    The Nevada Test Site (NTS) began operating Material Control and Accountability (MC&A) under the Safeguards First Principle Initiative (SFPI), a risk-based and cost-effective program, in December 2006. The NTS SFPI Comprehensive Assessment of Safeguards Systems (COMPASS) Model is made up of specific elements (MC&A plan, graded safeguards, accounting systems, measurements, containment, surveillance, physical inventories, shipper/receiver differences, assessments/performance tests) and various sub-elements, which are each assigned effectiveness and contribution factors that when weighted and rated reflect the health of the MC&A program. The MC&A Cost Model, using an Excel workbook, calculates budget and/or actual costs using these same elements/sub-elements resulting in total costs and effectiveness costs per element/sub-element. These calculations allow management to identify how costs are distributed for each element/sub-element. The Cost Model, as part of the SFPI program review process, enables management to determine if spending is appropriate for each element/sub-element.

  19. A new analytical model for thermal stresses in multi-phase materials and lifetime prediction methods

    Institute of Scientific and Technical Information of China (English)

    Ladislav Ceniga

    2008-01-01

    Based on the fundamental equations of the mechanics of solid continuum, the paper employs an ana-lytical model for determination of elastic thermal stresses in isotropic continuum represented by periodically distributed spherical particles with different distributions in an infinite matrix, imaginarily divided into identical cells with dimen-sions equal to inter-particle distances, containing a central spherical particle with or without a spherical envelope on the particle surface. Consequently, the multi-particle-(envelope)-matrix system, as a model system regarding the analytical modelling, is applicable to four types of multi-phase mate-rials. As functions of the particle volume fraction v, the inter-particle distances d1, d2, d3 along three mutually per-pendicular axes, and the particle and envelope radii, R1 and Re, respectively, the thermal stresses within the cell, are originated during a cooling process as a consequence of the difference in thermal expansion coefficients of phases rep-resented by the matrix, envelope and particle. Analytical-(experimental)-computational lifetime prediction methods for multi-phase materials are proposed, which can be used in engineering with appropriate values of parameters of real multi-phase materials.

  20. The Yale Cost Model and cost centres: servant or master?

    Science.gov (United States)

    Rigby, E

    1993-01-01

    Cost accounting describes that aspect of accounting which collects, allocates and controls the cost of producing a service. Costing information is primarily reported to management to enable control of costs and to ensure the financial viability of units, departments and divisions. As costing studies continue to produce estimates of Diagnosis Related Group (DRG) costs in New South Wales hospitals, as well as in other states, costs for different hospitals are being externally compared, using a tool which is usually related to internal management and reporting. Comparability of costs is assumed even though accounting systems differ. This paper examines the cost centre structures at five major teaching hospitals in Sydney. It describes the similarities and differences in how the cost centres were constituted, and then details the line items of expenditure that are charged to each cost centre. The results of a comparative study of a medical specialty are included as evidence of different costing methodologies in the hospitals. The picture that emerged from the study is that the hospitals are constituting their cost centres to meet their internal management needs, that is, to know the cost of running a ward or nursing unit, a medical specialty, department and so on. The rationale for the particular cost centre construction was that cost centre managers could manage and control costs and assign responsibility. There are variations in procedures for assigning costs to cost centres, and the question is asked 'Do these variations in procedures make a material difference to our ability to compare costs per Diagnosis Related Group at the various hospitals?' It is contended that the accounting information, which is produced as a result of different practices, is primarily for internal management, not external comparison. It would be better for hospitals to compare their estimated costs per Diagnosis Related Group to an internal standard cost rather than the costs from other

  1. Hospital Case Cost Estimates Modelling - Algorithm Comparison

    CERN Document Server

    Andru, Peter

    2008-01-01

    Ontario (Canada) Health System stakeholders support the idea and necessity of the integrated source of data that would include both clinical (e.g. diagnosis, intervention, length of stay, case mix group) and financial (e.g. cost per weighted case, cost per diem) characteristics of the Ontario healthcare system activities at the patient-specific level. At present, the actual patient-level case costs in the explicit form are not available in the financial databases for all hospitals. The goal of this research effort is to develop financial models that will assign each clinical case in the patient-specific data warehouse a dollar value, representing the cost incurred by the Ontario health care facility which treated the patient. Five mathematical models have been developed and verified using real dataset. All models can be classified into two groups based on their underlying method: 1. Models based on using relative intensity weights of the cases, and 2. Models based on using cost per diem.

  2. Cost-Benefit Assessment of Inspection and Repair Planning for Ship Structures Considering Corrosion Model Uncertainty

    Institute of Scientific and Technical Information of China (English)

    LI Dian-qing; TANG Wen-yong; ZHANG Sheng-kun

    2005-01-01

    Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective inspection. This paper aims to propose a cost-benefit assessment model of risk-based inspection and repair planning for ship structures subjected to corrosion deterioration. Then, the benefit-cost ratio is taken to be an index for the selection of the optimal inspection and repair strategy. The planning problem is formulated as an optimization problem where the benefit-cost ratio for the expected lifetime is maximized with a constraint on the minimum acceptable reliability index. To account for the effect of corrosion model uncertainty on the cost-benefit assessment, two corrosion models, namely, Paik's model and Guedes Soares' model, are adopted for analysis. A numerical example is presented to illustrate the proposed method. Sensitivity studies are also provided. The results indicate that the proposed method of risk-based cost-benefit analysis can effectively integrate the economy with reliability of the inspection and repair planning. A balance can be achieved between the risk cost and total expected inspection and repair costs with the proposed method, which is very effective in selecting the optimal inspection and repair strategy. It is pointed out that the corrosion model uncertainty and parametric uncertainty have a significant impact on the cost-benefit assessment of inspection and repair planning.

  3. A CTRW-based model of time-resolved fluorescence lifetime imaging in a turbid medium.

    Science.gov (United States)

    Chernomordik, Victor; Gandjbakhche, Amir H; Hassan, Moinuddin; Pajevic, Sinisa; Weiss, George H

    2010-12-01

    We develop an analytic model of time-resolved fluorescent imaging of photons migrating through a semi-infinite turbid medium bounded by an infinite plane in the presence of a single stationary point fluorophore embedded in the medium. In contrast to earlier models of fluorescent imaging in which photon motion is assumed to be some form of continuous diffusion process, the present analysis is based on a continuous-time random walk (CTRW) on a simple cubic lattice, the object being to estimate the position and lifetime of the fluorophore. Such information can provide information related to local variations in pH and temperature with potential medical significance. Aspects of the theory were tested using time-resolved measurements of the fluorescence from small inclusions inside tissue-like phantoms. The experimental results were found to be in good agreement with theoretical predictions provided that the fluorophore was not located too close to the planar boundary, a common problem in many diffusive systems.

  4. Lifetime effectiveness of mifamurtide addition to chemotherapy in nonmetastatic and metastatic osteosarcoma: a Markov process model analysis.

    Science.gov (United States)

    Song, Hyun Jin; Lee, Jun Ah; Han, Euna; Lee, Eui-Kyung

    2015-09-01

    The mortality and progression rates in osteosarcoma differ depending on the presence of metastasis. A decision model would be useful for estimating long-term effectiveness of treatment with limited clinical trial data. The aim of this study was to explore the lifetime effectiveness of the addition of mifamurtide to chemotherapy for patients with metastatic and nonmetastatic osteosarcoma. The target population was osteosarcoma patients with or without metastasis. A Markov process model was used, whose time horizon was lifetime with a starting age of 13 years. There were five health states: disease-free (DF), recurrence, post-recurrence disease-free, post-recurrence disease-progression, and death. Transition probabilities of the starting state, DF, were calculated from the INT-0133 clinical trials for chemotherapy with and without mifamurtide. Quality-adjusted life-years (QALY) increased upon addition of mifamurtide to chemotherapy by 10.5 % (10.13 and 9.17 QALY with and without mifamurtide, respectively) and 45.2 % (7.23 and 4.98 QALY with and without mifamurtide, respectively) relative to the lifetime effectiveness of chemotherapy in nonmetastatic and metastatic osteosarcoma, respectively. Life-years gained (LYG) increased by 10.1 % (13.10 LYG with mifamurtide and 11.90 LYG without mifamurtide) in nonmetastatic patients and 42.2 % (9.43 LYG with mifamurtide and 6.63 LYG without mifamurtide) in metastatic osteosarcoma patients. The Markov model analysis showed that chemotherapy with mifamurtide improved the lifetime effectiveness compared to chemotherapy alone in both nonmetastatic and metastatic osteosarcoma. Relative effectiveness of the therapy was higher in metastatic than nonmetastatic osteosarcoma over lifetime. However, absolute lifetime effectiveness was higher in nonmetastatic than metastatic osteosarcoma.

  5. Endurance degradation and lifetime model of p-channel floating gate flash memory device with 2T structure

    Science.gov (United States)

    Wei, Jiaxing; Liu, Siyang; Liu, Xiaoqiang; Sun, Weifeng; Liu, Yuwei; Liu, Xiaohong; Hou, Bo

    2017-08-01

    The endurance degradation mechanisms of p-channel floating gate flash memory device with two-transistor (2T) structure are investigated in detail in this work. With the help of charge pumping (CP) measurements and Sentaurus TCAD simulations, the damages in the drain overlap region along the tunnel oxide interface caused by band-to-band (BTB) tunneling programming and the damages in the channel region resulted from Fowler-Nordheim (FN) tunneling erasure are verified respectively. Furthermore, the lifetime model of endurance characteristic is extracted, which can extrapolate the endurance degradation tendency and predict the lifetime of the device.

  6. An assessment of electric vehicles: technology, infrastructure requirements, greenhouse-gas emissions, petroleum use, material use, lifetime cost, consumer acceptance and policy initiatives.

    Science.gov (United States)

    Delucchi, M A; Yang, C; Burke, A F; Ogden, J M; Kurani, K; Kessler, J; Sperling, D

    2014-01-13

    Concerns about climate change, urban air pollution and dependence on unstable and expensive supplies of foreign oil have led policy-makers and researchers to investigate alternatives to conventional petroleum-fuelled internal-combustion-engine vehicles in transportation. Because vehicles that get some or all of their power from an electric drivetrain can have low or even zero emissions of greenhouse gases (GHGs) and urban air pollutants, and can consume little or no petroleum, there is considerable interest in developing and evaluating advanced electric vehicles (EVs), including pure battery-electric vehicles, plug-in hybrid electric vehicles and hydrogen fuel-cell electric vehicles. To help researchers and policy-makers assess the potential of EVs to mitigate climate change and reduce petroleum use, this paper discusses the technology of EVs, the infrastructure needed for their development, impacts on emissions of GHGs, petroleum use, materials use, lifetime costs, consumer acceptance and policy considerations.

  7. Modeling lifetime data with multiple causes using cause specific reversed hazard rates

    Directory of Open Access Journals (Sweden)

    Paduthol Godan Sankaran

    2014-09-01

    Full Text Available In this paper we introduce and study cause specific reversed hazard rates in the context of left censored lifetime data with multiple causes. Nonparametric inference procedure for left censored lifetime data with multiple causes using cause specific reversed hazard rate is discussed. Asymptotic properties of the estimators are studied. Simulation studies are conducted to assess the efficiency of the estimators. Further, the proposed method is applied to mice mortality data (Hoel 1972 and Australian twin data (Duffy et al. 1990.

  8. Energy Savings Lifetimes and Persistence

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, Ian M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schiller, Steven R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Todd, Annika [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Billingsley, Megan A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goldman, Charles A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schwartz, Lisa C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-02-01

    This technical brief explains the concepts of energy savings lifetimes and savings persistence and discusses how program administrators use these factors to calculate savings for efficiency measures, programs and portfolios. Savings lifetime is the length of time that one or more energy efficiency measures or activities save energy, and savings persistence is the change in savings throughout the functional life of a given efficiency measure or activity. Savings lifetimes are essential for assessing the lifecycle benefits and cost effectiveness of efficiency activities and for forecasting loads in resource planning. The brief also provides estimates of savings lifetimes derived from a national collection of costs and savings for electric efficiency programs and portfolios.

  9. Determination of the atmospheric lifetime and global warming potential of sulfur hexafluoride using a three-dimensional model

    Science.gov (United States)

    Kovács, Tamás; Feng, Wuhu; Totterdill, Anna; Plane, John M. C.; Dhomse, Sandip; Gómez-Martín, Juan Carlos; Stiller, Gabriele P.; Haenel, Florian J.; Smith, Christopher; Forster, Piers M.; García, Rolando R.; Marsh, Daniel R.; Chipperfield, Martyn P.

    2017-01-01

    We have used the Whole Atmosphere Community Climate Model (WACCM), with an updated treatment of loss processes, to determine the atmospheric lifetime of sulfur hexafluoride (SF6). The model includes the following SF6 removal processes: photolysis, electron attachment and reaction with mesospheric metal atoms. The Sodankylä Ion Chemistry (SIC) model is incorporated into the standard version of WACCM to produce a new version with a detailed D region ion chemistry with cluster ions and negative ions. This is used to determine a latitude- and altitude-dependent scaling factor for the electron density in the standard WACCM in order to carry out multi-year SF6 simulations. The model gives a mean SF6 lifetime over an 11-year solar cycle (τ) of 1278 years (with a range from 1120 to 1475 years), which is much shorter than the currently widely used value of 3200 years, due to the larger contribution (97.4 %) of the modelled electron density to the total atmospheric loss. The loss of SF6 by reaction with mesospheric metal atoms (Na and K) is far too slow to affect the lifetime. We investigate how this shorter atmospheric lifetime impacts the use of SF6 to derive stratospheric age of air. The age of air derived from this shorter lifetime SF6 tracer is longer by 9 % in polar latitudes at 20 km compared to a passive SF6 tracer. We also present laboratory measurements of the infrared spectrum of SF6 and find good agreement with previous studies. We calculate the resulting radiative forcings and efficiencies to be, on average, very similar to those reported previously. Our values for the 20-, 100- and 500-year global warming potentials are 18 000, 23 800 and 31 300, respectively.

  10. Analysis of Implementing Lifetime Energy Cost, Including Fully Burdened Cost of Fuel and Energy Footprints of Contractors, as Mandatory Decision Factors in Navy Acquisition

    Science.gov (United States)

    2010-06-01

    25 3. Green Building in Government Construction Contracting, American Bar Association .............................. 26 III. METHODOLOGY...Energy Efficiency Project SFG Senior Focus Group TOC Total Ownership Cost USGBC United States Green Building Counsel xv ACKNOWLEDGMENTS...the currency market fluctuated, and thus would not necessarily indicate an increase or decrease in efficiency. 3. Green Building in Government

  11. Modeling the fiscal costs and benefits of alternative treatment strategies in the United Kingdom for chronic Hepatitis C.

    Science.gov (United States)

    Connolly, Mark P; Kotsopoulos, Nikos; Ustianowski, Andrew

    2017-09-05

    Hepatitis C (HCV) infection causes substantial direct health costs, but also impacts broader societal and governmental costs, such as tax revenue and social protection benefits. This study investigated the broader fiscal costs and benefits of curative interventions for chronic Hepatitis C (CHC) that allow individuals to avoid long-term HCV attributed health conditions. A prospective cohort model, assessing the long-term fiscal consequences of policy decisions, was developed for HCV infected individuals, following the generational accounting analytic framework that combines age-specific lifetime gross taxes paid and governmental transfers received (i.e. healthcare and social support costs). The analysis assessed the burden of a theoretical cohort of untreated HCV infected patients with the alternative of treating these patients with a highly efficacious curative intervention (ledipasvir/sofosbuvir [LDV/SOF]). It also compared treating patients at all fibrosis stages (Stages F0-F4) compared to late treatment (Stage F4). Based on projected lifetime work activity and taxes paid, the treated cohort paid an additional £5,900 per patient compared to the untreated cohort. Lifetime government disability costs of £97,555 and £125,359 per patient for treated cohort vs no treatment cohort were estimated, respectively. Lifetime direct healthcare costs in the treated cohort were £32,235, compared to non-treated cohort of £26,424, with an incremental healthcare costs increase of £5,901 per patient. The benefit cost ratio (BCR) of total government benefits and savings relative to government treatment costs (including LDV/SOF) ranged from 1.8-5.6. Treating patients early resulted in 77% less disability costs, 43% lower healthcare costs, and 33% higher tax revenue. The ability to cure Hepatitis C offers considerable fiscal benefits beyond direct medical costs and savings attributed to reduced disability costs, public allowances, and improved tax revenue. Changes in parameters

  12. Portfolio Optimization Model with Transaction Costs

    Institute of Scientific and Technical Information of China (English)

    Shu-ping Chen; Chong Li; Sheng-hong Li; Xiong-wei Wu

    2002-01-01

    The purpose of the article is to formulate, under the l∞ risk measure, a model of portfolio selection with transaction costs and then investigate the optimal strategy within the proposed. The characterization of a optimal strategy and the efficient algorithm for finding the optimal strategy are given.

  13. Cost Optimization of Product Families using Analytic Cost Models

    DEFF Research Database (Denmark)

    Brunø, Thomas Ditlev; Nielsen, Peter

    2012-01-01

    This paper presents a new method for analysing the cost structure of a mass customized product family. The method uses linear regression and backwards selection to reduce the complexity of a data set describing a number of historical product configurations and incurred costs. By reducing the data...... set, the configuration variables which best describe the variation in product costs are identified. The method is tested using data from a Danish manufacturing company and the results indicate that the method is able to identify the most critical configuration variables. The method can be applied...... in product family redesign projects focusing on cost reduction to identify which modules contribute the most to cost variation and should thus be optimized....

  14. Cost Optimization of Product Families using Analytic Cost Models

    DEFF Research Database (Denmark)

    Brunø, Thomas Ditlev; Nielsen, Peter

    2012-01-01

    This paper presents a new method for analysing the cost structure of a mass customized product family. The method uses linear regression and backwards selection to reduce the complexity of a data set describing a number of historical product configurations and incurred costs. By reducing the data...... set, the configuration variables which best describe the variation in product costs are identified. The method is tested using data from a Danish manufacturing company and the results indicate that the method is able to identify the most critical configuration variables. The method can be applied...... in product family redesign projects focusing on cost reduction to identify which modules contribute the most to cost variation and should thus be optimized....

  15. Activity based costing model for inventory valuation

    Directory of Open Access Journals (Sweden)

    Vineet Chouhan

    2017-03-01

    Full Text Available Activity-Based-Model (ABC is used for the purpose of significant improvement for overhead accounting systems by providing the best information required for managerial decision. This pa-per discusses implacability of ABC technique on inventory valuation as a management account-ing innovation. In order to prove the applicability of ABC for inventory control a material driven medium-sized and privately owned company from engineering (iron and steel industry is select-ed and by analysis of its production process and its material dependency and use of indirect in-ventory, an ABC model is explored for better inventory control. The case revealed that the ne-cessity of ABC in the area of inventory control is significant. The company is not only able to increase its quality of decision but also it can significantly analyze its cost of direct material cost, valuation of direct material and use its implications for better decision making.

  16. QSO Lifetimes

    CERN Document Server

    Martini, P

    2003-01-01

    The QSO lifetime t_Q is one of the most fundamental quantities for understanding black hole and QSO evolution, yet it remains uncertain by several orders of magnitude. If t_Q is long, then only a small fraction of galaxies went through a luminous QSO phase. In contrast, a short lifetime would require most galaxies today to have undergone a QSO phase in their youth. The current best estimates or constraints on t_Q from black hole demographics and the radiative properties of QSOs vary from at least 10^6 to 10^8 years. This broad range still allows both possibilities: that QSOs were either a rare or a common stage of galaxy evolution. These constraints also do not rule out the possibility that QSO activity is episodic, with individual active periods much shorter than the total active lifetime. In the next few years a variety of additional observational constraints on the lifetimes of QSOs will become available, including clustering measurements and the proximity effect. These new constraints can potentially dete...

  17. The Atmospheric Muon Lifetime, with the Lead Absorption Potential for Muons and References to the Standard Model of Particle Physics

    Science.gov (United States)

    Barazandeh, Cioli; Gutarra-Leon, Angel; Majewski, Walerian

    2017-01-01

    Muon is one of twelve fundamental particles and has the longest free-particle lifetime. It decays into three leptons through an exchange of weak vector bosons W +/W-. Muons are present in atmospheric secondary cosmic rays and reach the sea level. By detecting the time delay between arrival of muons and appearance of decay electrons in a scintillation detector, we will measure muon's lifetime at rest. From the lifetime we can find the ratio gw /MW of the weak coupling constant gw (a weak analog of the electric charge) to mass of the W-boson MW. Vacuum expectation value v of the Higgs field, which determines masses Standard Model (SM) particles, can be calculated as v =2MWc2/gw =(τmμc2/6π3\\hcirc)1/4mμc2 regarding muon mass mμ and muon lifetime τ only. Using the experimental value for MWc2 = 80.4 GeV, we will find weak coupling constant gw. With the SM relation e =gwsin θ√ hcε0 and experimental value of the Z0-photon weak mixing angle θ = 29o we use our muon lifetime to find the elementary electric charge e value. In this experiment we will also determine the sea level fluxes of low-energy (<160 MeV) and high-energy cosmic muons, then will shield the detector with varying thicknesses of lead plates and from the new values of fluxes find the energy-dependent muon stopping power in lead.

  18. Modeled black carbon radiative forcing and atmospheric lifetime in AeroCom Phase II constrained by aircraft observations

    Science.gov (United States)

    Samset, B. H.; Myhre, G.; Herber, A.; Kondo, Y.; Li, S.-M.; Moteki, N.; Koike, M.; Oshima, N.; Schwarz, J. P.; Balkanski, Y.; Bauer, S. E.; Bellouin, N.; Berntsen, T. K.; Bian, H.; Chin, M.; Diehl, T.; Easter, R. C.; Ghan, S. J.; Iversen, T.; Kirkevåg, A.; Lamarque, J.-F.; Lin, G.; Liu, X.; Penner, J. E.; Schulz, M.; Seland, Ø.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, K.; Zhang, K.

    2014-08-01

    Atmospheric black carbon (BC) absorbs solar radiation, and exacerbates global warming through exerting positive radiative forcing (RF). However, the contribution of BC to ongoing changes in global climate is under debate. Anthropogenic BC emissions, and the resulting distribution of BC concentration, are highly uncertain. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood. Here we discuss whether recent assessments may have overestimated present day BC radiative forcing in remote regions. We compare vertical profiles of BC concentration from four recent aircraft measurement campaigns to simulations by 13 aerosol models participating in the AeroCom Phase II intercomparision. An atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in remote ocean regions, in line with other recent studies. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in AeroCom Phase II median direct BC forcing, from fossil fuel and biofuel burning, over the industrial era. The sensitivity of modeled forcing to BC vertical profile and lifetime highlights an urgent need for further flight campaigns, close to sources and in remote regions, to provide improved quantification of BC effects for use in climate policy.

  19. Modelled black carbon radiative forcing and atmospheric lifetime in AeroCom Phase II constrained by aircraft observations

    Science.gov (United States)

    Samset, B. H.; Myhre, G.; Herber, A.; Kondo, Y.; Li, S.-M.; Moteki, N.; Koike, M.; Oshima, N.; Schwarz, J. P.; Balkanski, Y.; Bauer, S. E.; Bellouin, N.; Berntsen, T. K.; Bian, H.; Chin, M.; Diehl, T.; Easter, R. C.; Ghan, S. J.; Iversen, T.; Kirkevåg, A.; Lamarque, J.-F.; Lin, G.; Liu, X.; Penner, J. E.; Schulz, M.; Seland, Ø.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, K.; Zhang, K.

    2014-11-01

    Atmospheric black carbon (BC) absorbs solar radiation, and exacerbates global warming through exerting positive radiative forcing (RF). However, the contribution of BC to ongoing changes in global climate is under debate. Anthropogenic BC emissions, and the resulting distribution of BC concentration, are highly uncertain. In particular, long-range transport and processes affecting BC atmospheric lifetime are poorly understood. Here we discuss whether recent assessments may have overestimated present-day BC radiative forcing in remote regions. We compare vertical profiles of BC concentration from four recent aircraft measurement campaigns to simulations by 13 aerosol models participating in the AeroCom Phase II intercomparison. An atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in remote ocean regions, in line with other recent studies. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in AeroCom Phase II median direct BC forcing, from fossil fuel and biofuel burning, over the industrial era. The sensitivity of modelled forcing to BC vertical profile and lifetime highlights an urgent need for further flight campaigns, close to sources and in remote regions, to provide improved quantification of BC effects for use in climate policy.

  20. Modeled black carbon radiative forcing and atmospheric lifetime in AeroCom Phase II constrained by aircraft observations

    Directory of Open Access Journals (Sweden)

    B. H. Samset

    2014-08-01

    Full Text Available Atmospheric black carbon (BC absorbs solar radiation, and exacerbates global warming through exerting positive radiative forcing (RF. However, the contribution of BC to ongoing changes in global climate is under debate. Anthropogenic BC emissions, and the resulting distribution of BC concentration, are highly uncertain. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood. Here we discuss whether recent assessments may have overestimated present day BC radiative forcing in remote regions. We compare vertical profiles of BC concentration from four recent aircraft measurement campaigns to simulations by 13 aerosol models participating in the AeroCom Phase II intercomparision. An atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in remote ocean regions, in line with other recent studies. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in AeroCom Phase II median direct BC forcing, from fossil fuel and biofuel burning, over the industrial era. The sensitivity of modeled forcing to BC vertical profile and lifetime highlights an urgent need for further flight campaigns, close to sources and in remote regions, to provide improved quantification of BC effects for use in climate policy.

  1. Cost Effectiveness of Childhood Cochlear Implantation and Deaf Education in Nicaragua: A Disability Adjusted Life Year Model.

    Science.gov (United States)

    Saunders, James E; Barrs, David M; Gong, Wenfeng; Wilson, Blake S; Mojica, Karen; Tucci, Debara L

    2015-09-01

    Cochlear implantation (CI) is a common intervention for severe-to-profound hearing loss in high-income countries, but is not commonly available to children in low resource environments. Owing in part to the device costs, CI has been assumed to be less economical than deaf education for low resource countries. The purpose of this study is to compare the cost effectiveness of the two interventions for children with severe-to-profound sensorineural hearing loss (SNHL) in a model using disability adjusted life years (DALYs). Cost estimates were derived from published data, expert opinion, and known costs of services in Nicaragua. Individual costs and lifetime DALY estimates with a 3% discounting rate were applied to both two interventions. Sensitivity analysis was implemented to evaluate the effect on the discounted cost of five key components: implant cost, audiology salary, speech therapy salary, number of children implanted per year, and device failure probability. The costs per DALY averted are $5,898 and $5,529 for CI and deaf education, respectively. Using standards set by the WHO, both interventions are cost effective. Sensitivity analysis shows that when all costs set to maximum estimates, CI is still cost effective. Using a conservative DALY analysis, both CI and deaf education are cost-effective treatment alternatives for severe-to-profound SNHL. CI intervention costs are not only influenced by the initial surgery and device costs but also by rehabilitation costs and the lifetime maintenance, device replacement, and battery costs. The major CI cost differences in this low resource setting were increased initial training and infrastructure costs, but lower medical personnel and surgery costs.

  2. Health and economic impact of combining metformin with nateglinide to achieve glycemic control: Comparison of the lifetime costs of complications in the U.K

    Directory of Open Access Journals (Sweden)

    Salas Maribel

    2004-04-01

    Full Text Available Abstract Background To reduce the likelihood of complications in persons with type 2 diabetes, it is critical to control hyperglycaemia. Monotherapy with metformin or insulin secretagogues may fail to sustain control after an initial reduction in glycemic levels. Thus, combining metformin with other agents is frequently necessary. These analyses model the potential long-term economic and health impact of using combination therapy to improve glycemic control. Methods An existing model that simulates the long-term course of type 2 diabetes in relation to glycosylated haemoglobin (HbA1c and post-prandial glucose (PPG was used to compare the combination of nateglinide with metformin to monotherapy with metformin. Complication rates were estimated for major diabetes-related complications (macrovascular and microvascular based on existing epidemiologic studies and clinical trial data. Utilities and costs were estimated using data collected in the United Kingdom Prospective Diabetes Study (UKPDS. Survival, life years gained (LYG, quality-adjusted life years (QALY, complication rates and associated costs were estimated. Costs were discounted at 6% and benefits at 1.5% per year. Results Combination therapy was predicted to reduce complication rates and associated costs compared with metformin. Survival increased by 0.39 (0.32 discounted and QALY by 0.46 years (0.37 discounted implying costs of £6,772 per discounted LYG and £5,609 per discounted QALY. Sensitivity analyses showed the results to be consistent over broad ranges. Conclusion Although drug treatment costs are increased by combination therapy, this cost is expected to be partially offset by a reduction in the costs of treating long-term diabetes complications.

  3. Fleet Replacement Squadron consolidation : a cost model applied.

    OpenAIRE

    Maholchic, Robert M.

    1991-01-01

    The consolidation of Fleet Replacement Squadrons (FRS) represents one method of achieving planned force reductions. This thesis utilizes the Cost of Base Realignment Actions (COBRA) cost model to develop cost estimates for determination of the cost effective site location. The A-6 FRS consolidation is used as a case study. Data were compiled using completed Functional Wing studies as well as local information sources. A comparison between the cost estimates provided by the COBRA cost model fo...

  4. Estimating the long-term effects of in vitro fertilization in Greece: an analysis based on a lifetime-investment model

    Directory of Open Access Journals (Sweden)

    Fragoulakis V

    2013-06-01

    Full Text Available Vassilis Fragoulakis, Nikolaos ManiadakisNational School of Public Health, Department of Health Services Management, Athens, GreeceObjective: To quantify the economic effects of a child conceived by in vitro fertilization (IVF in terms of net tax revenue from the state's perspective in Greece.Methods: Based on previous international experience, a mathematical model was developed to assess the lifetime productivity of a single individual and his/her lifetime transactions with governmental agencies. The model distinguished among three periods in the economic life cycle of an individual: (1 early life, when the government primarily contributes resources through child tax credits, health care, and educational expenses; (2 employment, when individuals begin returning resources through taxes; and (3 retirement, when the government expends additional resources on pensions and health care. The cost of a live birth with IVF was based on the modification of a previously published model developed by the authors. All outcomes were discounted at a 3% discount rate. The data inputs – namely, the economic or demographic variables – were derived from the National Statistical Secretariat of Greece and other relevant sources. To deal with uncertainty, bias-corrected uncertainty intervals (UIs were calculated based on 5000 Monte Carlo simulations. In addition, to examine the robustness of our results, other one-way sensitivity analyses were also employed.Results: The cost of IVF per birth was estimated at €17,015 (95% UI: €13,932–€20,200. The average projected income generated by an individual throughout his/her productive life was €258,070 (95% UI: €185,376–€339,831. In addition, his/her life tax contribution was estimated at €133,947 (95% UI: €100,126–€177,375, while the discounted governmental expenses for elderly and underage individuals were €67,624 (95% UI: €55,211–€83,930. Hence, the net present value of IVF was €60

  5. A Revision on Cost Elements of the EOQ Model

    Directory of Open Access Journals (Sweden)

    Asadabadi Mehdi Rajabi

    2016-04-01

    Full Text Available The overall objective of this paper is to investigate the fundamental cost elements of the traditional EOQ model and develop the model by expiring some of its unrealistic assumptions. Over the last few decades, there have been numerous studies developing the EOQ model, but the basic cost elements of the EOQ model have not been investigated efficiently. On the other hand, the capital cost of buying inventories seems to be important to be investigated separately as well as holding cost and ordering cost in the model. In this paper, the capital cost of the inventory and possible stepwise increases in holding and setup cost are taken into account to make a revised formula to compute the economic order quantity. The proposed model involves explicitly the capital cost of buying the inventories in the EOQ model to ensure the decision makers that their financial concerns are considered in the revised model and the new order quantity results the minimum total cost.

  6. Monte Carlo mixture model of lifetime cancer incidence risk from radiation exposure on shuttle and international space station

    Science.gov (United States)

    Peterson, L. E.; Cucinotta, F. A.; Wilson, J. W. (Principal Investigator)

    1999-01-01

    Estimating uncertainty in lifetime cancer risk for human exposure to space radiation is a unique challenge. Conventional risk assessment with low-linear-energy-transfer (LET)-based risk from Japanese atomic bomb survivor studies may be inappropriate for relativistic protons and nuclei in space due to track structure effects. This paper develops a Monte Carlo mixture model (MCMM) for transferring additive, National Institutes of Health multiplicative, and multiplicative excess cancer incidence risks based on Japanese atomic bomb survivor data to determine excess incidence risk for various US astronaut exposure profiles. The MCMM serves as an anchor point for future risk projection methods involving biophysical models of DNA damage from space radiation. Lifetime incidence risks of radiation-induced cancer for the MCMM based on low-LET Japanese data for nonleukemia (all cancers except leukemia) were 2.77 (90% confidence limit, 0.75-11.34) for males exposed to 1 Sv at age 45 and 2.20 (90% confidence limit, 0.59-10.12) for males exposed at age 55. For females, mixture model risks for nonleukemia exposed separately to 1 Sv at ages of 45 and 55 were 2.98 (90% confidence limit, 0.90-11.70) and 2.44 (90% confidence limit, 0.70-10.30), respectively. Risks for high-LET 200 MeV protons (LET=0.45 keV/micrometer), 1 MeV alpha-particles (LET=100 keV/micrometer), and 600 MeV iron particles (LET=180 keV/micrometer) were scored on a per particle basis by determining the particle fluence required for an average of one particle per cell nucleus of area 100 micrometer(2). Lifetime risk per proton was 2.68x10(-2)% (90% confidence limit, 0.79x10(-3)%-0. 514x10(-2)%). For alpha-particles, lifetime risk was 14.2% (90% confidence limit, 2.5%-31.2%). Conversely, lifetime risk per iron particle was 23.7% (90% confidence limit, 4.5%-53.0%). Uncertainty in the DDREF for high-LET particles may be less than that for low-LET radiation because typically there is very little dose-rate dependence

  7. On the Economic Order Quantity Model With Transportation Costs

    NARCIS (Netherlands)

    S.I. Birbil (Ilker); K. Bulbul; J.B.G. Frenk (Hans); H.M. Mulder (Henry)

    2009-01-01

    textabstractWe consider an economic order quantity type model with unit out-of-pocket holding costs, unit opportunity costs of holding, fixed ordering costs and general transportation costs. For these models, we analyze the associated optimization problem and derive an easy procedure for determining

  8. A simulation model to estimate cost-offsets for a disease-management program for chronic kidney disease.

    Science.gov (United States)

    Gandjour, Afschin; Tschulena, Ulrich; Steppan, Sonja; Gatti, Emanuele

    2015-04-01

    The aim of this paper is to develop a simulation model that analyzes cost-offsets of a hypothetical disease management program (DMP) for patients with chronic kidney disease (CKD) in Germany compared to no such program. A lifetime Markov model with simulated 65-year-old patients with CKD was developed using published data on costs and health status and simulating the progression to end-stage renal disease (ESRD), cardiovascular disease and death. A statutory health insurance perspective was adopted. This modeling study shows considerable potential for cost-offsets from a DMP for patients with CKD. The potential for cost-offsets increases with relative risk reduction by the DMP and baseline glomerular filtration rate. Results are most sensitive to the cost of dialysis treatment. This paper presents a general 'prototype' simulation model for the prevention of ESRD. The model allows for further modification and adaptation in future applications.

  9. Optimal pricing decision model based on activity-based costing

    Institute of Scientific and Technical Information of China (English)

    王福胜; 常庆芳

    2003-01-01

    In order to find out the applicability of the optimal pricing decision model based on conventional costbehavior model after activity-based costing has given strong shock to the conventional cost behavior model andits assumptions, detailed analyses have been made using the activity-based cost behavior and cost-volume-profitanalysis model, and it is concluded from these analyses that the theory behind the construction of optimal pri-cing decision model is still tenable under activity-based costing, but the conventional optimal pricing decisionmodel must be modified as appropriate to the activity-based costing based cost behavior model and cost-volume-profit analysis model, and an optimal pricing decision model is really a product pricing decision model construc-ted by following the economic principle of maximizing profit.

  10. A life cycle cost economics model for projects with uniformly varying operating costs. [management planning

    Science.gov (United States)

    Remer, D. S.

    1977-01-01

    A mathematical model is developed for calculating the life cycle costs for a project where the operating costs increase or decrease in a linear manner with time. The life cycle cost is shown to be a function of the investment costs, initial operating costs, operating cost gradient, project life time, interest rate for capital and salvage value. The results show that the life cycle cost for a project can be grossly underestimated (or overestimated) if the operating costs increase (or decrease) uniformly over time rather than being constant as is often assumed in project economic evaluations. The following range of variables is examined: (1) project life from 2 to 30 years; (2) interest rate from 0 to 15 percent per year; and (3) operating cost gradient from 5 to 90 percent of the initial operating costs. A numerical example plus tables and graphs is given to help calculate project life cycle costs over a wide range of variables.

  11. A life cycle cost economics model for projects with uniformly varying operating costs. [management planning

    Science.gov (United States)

    Remer, D. S.

    1977-01-01

    A mathematical model is developed for calculating the life cycle costs for a project where the operating costs increase or decrease in a linear manner with time. The life cycle cost is shown to be a function of the investment costs, initial operating costs, operating cost gradient, project life time, interest rate for capital and salvage value. The results show that the life cycle cost for a project can be grossly underestimated (or overestimated) if the operating costs increase (or decrease) uniformly over time rather than being constant as is often assumed in project economic evaluations. The following range of variables is examined: (1) project life from 2 to 30 years; (2) interest rate from 0 to 15 percent per year; and (3) operating cost gradient from 5 to 90 percent of the initial operating costs. A numerical example plus tables and graphs is given to help calculate project life cycle costs over a wide range of variables.

  12. Animated-simulation modeling facilitates clinical-process costing.

    Science.gov (United States)

    Zelman, W N; Glick, N D; Blackmore, C C

    2001-09-01

    Traditionally, the finance department has assumed responsibility for assessing process costs in healthcare organizations. To enhance process-improvement efforts, however, many healthcare providers need to include clinical staff in process cost analysis. Although clinical staff often use electronic spreadsheets to model the cost of specific processes, PC-based animated-simulation tools offer two major advantages over spreadsheets: they allow clinicians to interact more easily with the costing model so that it more closely represents the process being modeled, and they represent cost output as a cost range rather than as a single cost estimate, thereby providing more useful information for decision making.

  13. A Cost Model for Storage and Weeding Programs.

    Science.gov (United States)

    Lawrence, Gary S.

    1981-01-01

    Presents a simple cost model to analyze trade-offs involved in considering storage and weeding as alternatives to new construction for academic libraries. References are provided, and the Palmour cost model is presented as an appendix. (RAA)

  14. Coupled modeling of the competitive gettering of transition metals and impact on performance of lifetime sensitive devices

    Science.gov (United States)

    Yazdani, Armin; Chen, Renyu; Dunham, Scott T.

    2017-03-01

    This work models competitive gettering of metals (Cu, Ni, Fe, Mo, and W) by boron, phosphorus, and dislocation loops, and connects those results directly to device performance. Density functional theory calculations were first performed to determine the binding energies of metals to the gettering sites, and based on that, continuum models were developed to model the redistribution and trapping of the metals. Our models found that Fe is most strongly trapped by the dislocation loops while Cu and Ni are most strongly trapped by the P4V clusters formed in high phosphorus concentrations. In addition, it is found that none of the mentioned gettering sites are effective in gettering Mo and W. The calculated metal redistribution along with the associated capture cross sections and trap energy levels are passed to device simulation via the recombination models to calculate carrier lifetime and the resulting device performance. Thereby, a comprehensive and predictive TCAD framework is developed to optimize the processing conditions to maximize performance of lifetime sensitive devices.

  15. ABC model and the management of costs

    Directory of Open Access Journals (Sweden)

    Pravdić Predrag

    2016-01-01

    Full Text Available When a company has multiple objectives at the same time, they all must be considered and balanced when making any business decisions. Linking the markets, capital and resources so as to thus ensure the highest yield is, In fact, the search for competitive advantage as a basic condition for survival in a market economy. In highly detailed systems based on the management of costs or ABC (activity based costing systems, the cost of activities often result in erroneous evaluation of aggregate costs of the action. Improvements in information technology and monitoring decrease of technology costs enabled the ABC system to become a feasible system calculating costs in many organizations.

  16. Neutron lifetimes behavior analysis considering the two-region kinetic model in the IPEN/MB-01 reactor

    Science.gov (United States)

    Gonnelli, Eduardo; Diniz, Ricardo

    2014-11-01

    This is a complementary work about the behavior analysis of the neutron lifetimes that was developed in the IPEN/MB-01 nuclear reactor facility. The macroscopic neutron noise technique was experimentally employed using pulse mode detectors for two stages of control rods insertion, where a total of twenty levels of subcriticality have been carried out. It was also considered that the neutron reflector density was treated as an additional group of delayed neutrons, being a sophisticated approach in the two-region kinetic theoretical model.

  17. Modeling Uncertainty when Estimating IT Projects Costs

    OpenAIRE

    Winter, Michel; Mirbel, Isabelle; Crescenzo, Pierre

    2014-01-01

    In the current economic context, optimizing projects' cost is an obligation for a company to remain competitive in its market. Introducing statistical uncertainty in cost estimation is a good way to tackle the risk of going too far while minimizing the project budget: it allows the company to determine the best possible trade-off between estimated cost and acceptable risk. In this paper, we present new statistical estimators derived from the way IT companies estimate the projects' costs. In t...

  18. APT cost scaling: Preliminary indications from a Parametric Costing Model (PCM)

    Energy Technology Data Exchange (ETDEWEB)

    Krakowski, R.A.

    1995-02-03

    A Parametric Costing Model has been created and evaluate as a first step in quantitatively understanding important design options for the Accelerator Production of Tritium (APT) concept. This model couples key economic and technical elements of APT in a two-parameter search of beam energy and beam power that minimizes costs within a range of operating constraints. The costing and engineering depth of the Parametric Costing Model is minimal at the present {open_quotes}entry level{close_quotes}, and is intended only to demonstrate a potential for a more-detailed, cost-based integrating design tool. After describing the present basis of the Parametric Costing Model and giving an example of a single parametric scaling run derived therefrom, the impacts of choices related to resistive versus superconducting accelerator structures and cost of electricity versus plant availability ({open_quotes}load curve{close_quotes}) are reported. Areas of further development and application are suggested.

  19. A Critique of Aircraft Airframe Cost Models.

    Science.gov (United States)

    1977-09-01

    rframes Aircraft Cost Analysis 2C *3Si PACT [’Cor.rinu* an r+vrmm »lam ti omc +mmmfy mr.J tffonUtf t>f Met.* riutnfcor) see reverse side...numbers, however, the ASD Cost Escalation Re- ft port 110-C would give a factor of 1.44.) 6 Historiaal and Forecasted Aeronautical Cost Indices

  20. Simulating Star Clusters with the AMUSE Software Framework: I. Dependence of Cluster Lifetimes on Model Assumptions and Cluster Dissolution Modes

    CERN Document Server

    Whitehead, Alfred J; Vesperini, Enrico; Zwart, Simon Portegies

    2013-01-01

    We perform a series of simulations of evolving star clusters using AMUSE (the Astrophysical Multipurpose Software Environment), a new community-based multi-physics simulation package, and compare our results to existing work. These simulations model a star cluster beginning with a King model distribution and a selection of power-law initial mass functions, and contain a tidal cut-off. They are evolved using collisional stellar dynamics and include mass loss due to stellar evolution. After determining that the differences between AMUSE results and prior publications are understood, we explored the variation in cluster lifetimes due to the random realization noise introduced by transforming a King model to specific initial conditions. This random realization noise can affect the lifetime of a simulated star cluster by up to 30%. Two modes of star cluster dissolution were identified: a mass evolution curve that contains a run-away cluster dissolution with a sudden loss of mass, and a dissolution mode that does n...

  1. Modelled Black Carbon Radiative Forcing and Atmospheric Lifetime in AeroCom Phase II Constrained by Aircraft Observations

    Energy Technology Data Exchange (ETDEWEB)

    Samset, B. H.; Myhre, G.; Herber, Andreas; Kondo, Yutaka; Li, Shao-Meng; Moteki, N.; Koike, Makoto; Oshima, N.; Schwarz, Joshua P.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Chin, M.; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Lamarque, Jean-Francois; Lin, Guang; Liu, Xiaohong; Penner, Joyce E.; Schulz, M.; Seland, O.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; Zhang, Kai

    2014-11-27

    Black carbon (BC) aerosols absorb solar radiation, and are generally held to exacerbate global warming through exerting a positive radiative forcing1. However, the total contribution of BC to the ongoing changes in global climate is presently under debate2-8. Both anthropogenic BC emissions and the resulting spatial and temporal distribution of BC concentration are highly uncertain2,9. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood, leading to large estimated uncertainty in BC concentration at high altitudes and far from emission sources10. These uncertainties limit our ability to quantify both the historical, present and future anthropogenic climate impact of BC. Here we compare vertical profiles of BC concentration from four recent aircraft measurement campaigns with 13 state of the art aerosol models, and show that recent assessments may have overestimated present day BC radiative forcing. Further, an atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in transport dominated remote regions. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in the multi-model median direct BC forcing from fossil fuel and biofuel burning over the industrial era.

  2. Intelligent Cost Modeling Based on Soft Computing for Avionics Systems

    Institute of Scientific and Technical Information of China (English)

    ZHU Li-li; LI Zhuang-sheng; XU Zong-ze

    2006-01-01

    In parametric cost estimating, objections to using statistical Cost Estimating Relationships (CERs) and parametric models include problems of low statistical significance due to limited data points, biases in the underlying data, and lack of robustness. Soft Computing (SC) technologies are used for building intelligent cost models. The SC models are systemically evaluated based on their training and prediction of the historical cost data of airborne avionics systems. Results indicating the strengths and weakness of each model are presented. In general, the intelligent cost models have higher prediction precision, better data adaptability, and stronger self-learning capability than the regression CERs.

  3. A New Activity-Based Cost (ABC) Mathematical Model

    Institute of Scientific and Technical Information of China (English)

    JIANG Shuo; SONG Lei

    2003-01-01

    Along with the product price competition growing intensely, it is apparently important for reasonably distributing and counting cost. But, in sharing indirect cost, traditional cost accounting unveils the limitations increasingly, especially in authenticity of cost information. And the accounting theory circles and industry circles begin seeking one kind of new accurate cost calculation method, and the activity-based cost (ABC) method emerges as the times require. In this paper, we will build its mathematical model by the basic principle of ABC, and will improve its mathematical model further. We will establish its comparison mathematical model and make the ABC method go a step further to its practical application.

  4. Estimating the Costs of Educating Handicapped Children: A Resource-Cost Model Approach-Summary Report.

    Science.gov (United States)

    Hartman, William T.

    1981-01-01

    The resource cost model approach makes the programmatic aspects of special education explicit and links these with associated costs. It facilitates planning for education of handicapped children. An effective cost estimation plan was necessary because of recent political and legal mandates which established the educational rights of the…

  5. Injecting Abstract Interpretations into Linear Cost Models

    Directory of Open Access Journals (Sweden)

    David Cachera

    2010-06-01

    Full Text Available We present a semantics based framework for analysing the quantitative behaviour of programs with regard to resource usage. We start from an operational semantics equipped with costs. The dioid structure of the set of costs allows for defining the quantitative semantics as a linear operator. We then present an abstraction technique inspired from abstract interpretation in order to effectively compute global cost information from the program. Abstraction has to take two distinct notions of order into account: the order on costs and the order on states. We show that our abstraction technique provides a correct approximation of the concrete cost computations.

  6. Cost analysis of prenatal care using the activity-based costing model: a pilot study.

    Science.gov (United States)

    Gesse, T; Golembeski, S; Potter, J

    1999-01-01

    The cost of prenatal care in a private nurse-midwifery practice was examined using the activity-based costing system. Findings suggest that the activities of the nurse-midwife (the health care provider) constitute the major cost driver of this practice and that the model of care and associated, time-related activities influence the cost. This pilot study information will be used in the development of a comparative study of prenatal care, client education, and self care.

  7. SUPPLIES COSTS: AN EXPLORATORY STUDY WITH APPLICATION OF MEASUREMENT MODEL OF LOGISTICS COSTS

    OpenAIRE

    Ana Paula Ferreira Alves; José Vanderlei Silva Borba; Gilberto Tavares dos Santos; Artur Roberto Gibbon

    2013-01-01

    One of the main reasons for the difficulty in adopting an integrated method of calculation of logistics costs is still a lack of adequate information about costs. The management of the supply chain and identify its costs can provide information for their managers, with regard to decision making, generating competitive advantage. Some models of calculating logistics costs are proposed by Uelze (1974), Dias (1996), Goldratt (2002), Christopher (2007), Castiglioni (2009) and Borba & Gibbon (2009...

  8. Offshore Wind Balance-of-System Cost Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Maness, Michael; Stehly, Tyler; Maples, Ben; Mone, Christopher

    2015-09-29

    Offshore wind balance-of-system (BOS) costs contribute up to 70% of installed capital costs. Thus, it is imperative to understand the impact of these costs on project economics as well as potential cost trends for new offshore wind technology developments. As a result, the National Renewable Energy Laboratory (NREL) developed and recently updated a BOS techno-economic model using project cost estimates created from wind energy industry sources.

  9. Evaluation of Cost Models and Needs & Gaps Analysis

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad

    2014-01-01

    his report ’D3.1—Evaluation of Cost Models and Needs & Gaps Analysis’ provides an analysis of existing research related to the economics of digital curation and cost & benefit modelling. It reports upon the investigation of how well current models and tools meet stakeholders’ needs for calculating...... andcomparing financial information. Based on this evaluation, it aims to point out gaps that need to be bridged in order to increase the uptake of cost & benefit modelling and good practices that will enable costing and comparison of the costs of alternative scenarios—which in turn provides a starting point...... for amore efficient use of resources for digital curation. To facilitate and clarify the model evaluation the report first outlines a basic terminology and a generaldescription of the characteristics of cost and benefit models.The report then describes how the ten current and emerging cost and benefit...

  10. Lifetime cover in private insurance markets.

    Science.gov (United States)

    Brown, H Shelton; Connelly, Luke B

    2005-03-01

    In the last few decades, private health insurance rates have declined in many countries. In countries and states with community rating, a major cause is adverse selection. In order to address age-based adverse selection, Australia has recently begun a novel approach which imposes stiff penalties for buying private insurance later in life, when expected costs are higher. In this paper, we analyze Australia's Lifetime Cover in the context of a modified version of the Rothschild-Stiglitz insurance model (Rothschild and Stiglitz, 1976). We allow empirically-based probabilities to increase by age for low-risk types. The model highlights the shortcomings of the Australian plan. Based on empirically-based probabilities of illness, we predict that Lifetime Cover will not arrest adverse selection. The model has many policy implications for government regulation encouraging long-term health coverage.

  11. Wind turbine blade life-time assessment model for preventive planning of operation and maintenance

    DEFF Research Database (Denmark)

    Florian, Mihai; Sørensen, John Dalsgaard

    2014-01-01

    Out of the total wind turbine failure events, blade damage accounts for a substantial part, with some studies estimating it at around 23%. Current operation and maintenance (O&M) practices typically make use of corrective type maintenance as the basic approach, implying high costs for repair...

  12. Wind Turbine Blade Life-Time Assessment Model for Preventive Planning of Operation and Maintenance

    DEFF Research Database (Denmark)

    Florian, Mihai; Sørensen, John Dalsgaard

    2015-01-01

    Out of the total wind turbine failure events, blade damage accounts for a substantial part, with some studies estimating it at around 23%. Current operation and maintenance (O&M) practices typically make use of corrective type maintenance as the basic approach, implying high costs for repair...

  13. Cost damping and functional form in transport models

    DEFF Research Database (Denmark)

    Rich, Jeppe; Mabit, Stefan Lindhard

    2015-01-01

    take different forms and be represented as a non-linear-in-parameter form such as the well-known Box–Cox function. However, it could also be specified as non-linear-in-cost but linear-in-parameter forms, which are easier to estimate and improve model fit without increasing the number of parameters....... The specific contributions of the paper are as follows. Firstly, we discuss the phenomenon of cost damping in details and specifically why it occurs. Secondly, we provide a test of damping and an easy assessment of the (linear) damping rate for any variable by estimating two auxiliary linear models. This turns......Transport models allowing for cost damping are characterised by marginally decreasing cost sensitivities in demand. As a result, cost damping is a model extension of the simple linear-in-cost model requiring an appropriate non-linear link function between utility and cost. The link function may...

  14. Cost damping and functional form in transport models

    DEFF Research Database (Denmark)

    Rich, Jeppe; Mabit, Stefan Lindhard

    2016-01-01

    Transport models allowing for cost damping are characterised by marginally decreasing cost sensitivities in demand. As a result, cost damping is a model extension of the simple linear-in-cost model requiring an appropriate non-linear link function between utility and cost. The link function may...... take different forms and be represented as a non-linear-in-parameter form such as the well-known Box–Cox function. However, it could also be specified as non-linear-in-cost but linear-in-parameter forms, which are easier to estimate and improve model fit without increasing the number of parameters....... The specific contributions of the paper are as follows. Firstly, we discuss the phenomenon of cost damping in details and specifically why it occurs. Secondly, we provide a test of damping and an easy assessment of the (linear) damping rate for any variable by estimating two auxiliary linear models. This turns...

  15. Particle-particle correlations and lifetimes of composite nuclei: New tests for the evaporation model and for statistical equilibration

    Energy Technology Data Exchange (ETDEWEB)

    DeYoung, P.A.; Gelderloos, C.J.; Kortering, D.; Sarafa, J.; Zienert, K.; Gordon, M.S.; Fineman, B.J.; Gilfoyle, G.P.; Lu, X.; McGrath, R.L.; de Castro Rizzo, D.M.; Alexander, J.M.; Auger, G.; Kox, S.; Vaz, L.C.; Beck, C.; Henderson, D.J.; Kovar, D.G.; Vineyard, M.F. (Department of Physics, Hope College, Holland, Michigan 49423 (US) Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794 Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794 Argonne National Laboratory, Argonne, Illinois 60439)

    1990-05-01

    We present data for small-angle particle-particle correlations from the reactions 80, 140, 215, and 250 MeV {sup 16}O+{sup 27}Al{r arrow}{ital p}-{ital p} or {ital p}-{ital d}. The main features of these data are anticorrelations for small relative momenta ({le}25 MeV/{ital c}) that strengthen with increasing bombarding energy. Statistical model calculations have been performed to predict the mean lifetimes for each step of evaporative decay, and then simulate the trajectories of the particle pairs and the resulting particle correlations. This simulation accounts very well for the trends of the data and can provide an important new test for the hypothesis of equilibration on which the model is built.

  16. A corrected likelihood approach for the nonlinear transformation model with application to fluorescence lifetime measurements using exponential mixtures.

    Science.gov (United States)

    Rebafka, Tabea; Roueff, François; Souloumiac, Antoine

    2010-01-01

    A fast and efficient estimation method is proposed that compensates the distortion in nonlinear transformation models. A likelihood-based estimator is developed that can be computed by an EM-type algorithm. The consistency of the estimator is shown and its limit distribution is provided. The new estimator is particularly well suited for fluorescence lifetime measurements, where only the shortest arrival time of a random number of emitted fluorescence photons can be detected and where arrival times are often modeled by a mixture of exponential distributions. The method is evaluated on real and synthetic data. Compared to currently used methods in fluorescence, the new estimator should allow a reduction of the acquisition time of an order of magnitude.

  17. A cost-effectiveness model of genetic testing for the evaluation of families with hypertrophic cardiomyopathy.

    Science.gov (United States)

    Ingles, Jodie; McGaughran, Julie; Scuffham, Paul A; Atherton, John; Semsarian, Christopher

    2012-04-01

    Traditional management of families with hypertrophic cardiomyopathy (HCM) involves periodic lifetime clinical screening of family members, an approach that does not identify all gene carriers owing to incomplete penetrance and significant clinical heterogeneity. Limitations in availability and cost have meant genetic testing is not part of routine clinical management for many HCM families. To determine the cost-effectiveness of the addition of genetic testing to HCM family management, compared with clinical screening alone. A probabilistic Markov decision model was used to determine cost per quality-adjusted life-year and cost for each life-year gained when genetic testing is included in the management of Australian families with HCM, compared with the conventional approach of periodic clinical screening alone. The incremental cost-effectiveness ratio (ICER) was $A785 (£510 or €587) per quality-adjusted life-year gained, and $A12 720 (£8261 or €9509) per additional life-year gained making genetic testing a very cost-effective strategy. Sensitivity analyses showed that the cost of proband genetic testing was an important variable. As the cost of proband genetic testing decreased, the ICER decreased and was cost saving when the cost fell below $A248 (£161 or €185). In addition, the mutation identification rate was also important in reducing the overall ICER, although even at the upper limits, the ICER still fell well within accepted willingness to pay bounds. The addition of genetic testing to the management of HCM families is cost-effective in comparison with the conventional approach of regular clinical screening. This has important implications for the evaluation of families with HCM, and suggests that all should have access to specialised cardiac genetic clinics that can offer genetic testing.

  18. A Deterministic Inventory/Production Model with General Inventory Cost Rate Function and Concave Production Costs

    NARCIS (Netherlands)

    S.I. Birbil (Ilker); J.B.G. Frenk (Hans); Z.P. Bayindir (Pelin)

    2004-01-01

    textabstractWe present a thorough analysis of the economic order quantity model with shortages under a general inventory cost rate function and concave production costs. By using some standard results from convex analysis, we show that the model exhibits a composite concave-convex structure.

  19. Predicting Market Impact Costs Using Nonparametric Machine Learning Models.

    Directory of Open Access Journals (Sweden)

    Saerom Park

    Full Text Available Market impact cost is the most significant portion of implicit transaction costs that can reduce the overall transaction cost, although it cannot be measured directly. In this paper, we employed the state-of-the-art nonparametric machine learning models: neural networks, Bayesian neural network, Gaussian process, and support vector regression, to predict market impact cost accurately and to provide the predictive model that is versatile in the number of variables. We collected a large amount of real single transaction data of US stock market from Bloomberg Terminal and generated three independent input variables. As a result, most nonparametric machine learning models outperformed a-state-of-the-art benchmark parametric model such as I-star model in four error measures. Although these models encounter certain difficulties in separating the permanent and temporary cost directly, nonparametric machine learning models can be good alternatives in reducing transaction costs by considerably improving in prediction performance.

  20. Predicting Market Impact Costs Using Nonparametric Machine Learning Models.

    Science.gov (United States)

    Park, Saerom; Lee, Jaewook; Son, Youngdoo

    2016-01-01

    Market impact cost is the most significant portion of implicit transaction costs that can reduce the overall transaction cost, although it cannot be measured directly. In this paper, we employed the state-of-the-art nonparametric machine learning models: neural networks, Bayesian neural network, Gaussian process, and support vector regression, to predict market impact cost accurately and to provide the predictive model that is versatile in the number of variables. We collected a large amount of real single transaction data of US stock market from Bloomberg Terminal and generated three independent input variables. As a result, most nonparametric machine learning models outperformed a-state-of-the-art benchmark parametric model such as I-star model in four error measures. Although these models encounter certain difficulties in separating the permanent and temporary cost directly, nonparametric machine learning models can be good alternatives in reducing transaction costs by considerably improving in prediction performance.

  1. Health economic evaluation of Human Papillomavirus vaccines in women from Venezuela by a lifetime Markov cohort model.

    Science.gov (United States)

    Bardach, Ariel Esteban; Garay, Osvaldo Ulises; Calderón, María; Pichón-Riviére, Andrés; Augustovski, Federico; Martí, Sebastián García; Cortiñas, Paula; Gonzalez, Marino; Naranjo, Laura T; Gomez, Jorge Alberto; Caporale, Joaquín Enzo

    2017-02-02

    Cervical cancer (CC) and genital warts (GW) are a significant public health issue in Venezuela. Our objective was to assess the cost-effectiveness of the two available vaccines, bivalent and quadrivalent, against Human Papillomavirus (HPV) in Venezuelan girls in order to inform decision-makers. A previously published Markov cohort model, informed by the best available evidence, was adapted to the Venezuelan context to evaluate the effects of vaccination on health and healthcare costs from the perspective of the healthcare payer in an 11-year-old girls cohort of 264,489. Costs and quality-adjusted life years (QALYs) were discounted at 5%. Eight scenarios were analyzed to depict the cost-effectiveness under alternative vaccine prices, exchange rates and dosing schemes. Deterministic and probabilistic sensitivity analyses were performed. Compared to screening only, the bivalent and quadrivalent vaccines were cost-saving in all scenarios, avoiding 2,310 and 2,143 deaths, 4,781 and 4,431 CCs up to 18,459 GW for the quadrivalent vaccine and gaining 4,486 and 4,395 discounted QALYs respectively. For both vaccines, the main determinants of variations in the incremental costs-effectiveness ratio after running deterministic and probabilistic sensitivity analyses were transition probabilities, vaccine and cancer-treatment costs and HPV 16 and 18 distribution in CC cases. When comparing vaccines, none of them was consistently more cost-effective than the other. In sensitivity analyses, for these comparisons, the main determinants were GW incidence, the level of cross-protection and, for some scenarios, vaccines costs. Immunization with the bivalent or quadrivalent HPV vaccines showed to be cost-saving or cost-effective in Venezuela, falling below the threshold of one Gross Domestic Product (GDP) per capita (104,404 VEF) per QALY gained. Deterministic and probabilistic sensitivity analyses confirmed the robustness of these results.

  2. Model prediction for ranking lead-acid batteries according to expected lifetime in renewable energy systems and autonomous power-supply systems

    DEFF Research Database (Denmark)

    Schiffer, J.; Sauer, D.U.; Bindner, Henrik W.

    2007-01-01

    system sizing and different battery technologies on battery lifetime. It is a tool for system designers and system operators to select appropriate batteries, to do a proper system design (sizing of the battery, power generators and loads), and to implement an optimized operation strategy (end......Predicting the lifetime of lead-acid batteries in applications with irregular operating conditions such as partial state-of-charge cycling, varying depth-of-discharge and different times between full charging is known as a difficult task. Experimental investigations in the laboratory are difficult...... into account are based on a detailed analysis and understanding of ageing processes in lead-acid batteries. The ' normal ' user can adapt the model to different battery types simply from the data sheet information on cycle lifetime and float lifetime. (C) 2006 Elsevier B.V. All rights reserved....

  3. Electro-thermal Modeling for Junction Temperature Cycling-Based Lifetime Prediction of a Press-Pack IGBT 3L-NPC-VSC Applied to Large Wind Turbines

    DEFF Research Database (Denmark)

    Senturk, Osman Selcuk; Munk-Nielsen, Stig; Teodorescu, Remus;

    2011-01-01

    reliability is investigated regarding IGBT lifetime based on junction temperature cycling for the grid-side press-pack IGBT 3L-NPC-VSC, which is a state-of-the art high reliability solution. In order to acquire IGBT junction temperatures for given wind power profiles and to use them in IGBT lifetime...... prediction, the converter electro-thermal model including electrical, power loss, and dynamical thermal models is developed with the main focus on the thermal modeling regarding converter topology, switch technology, and physical structure. Moreover, these models are simplified for their practical...

  4. Offshore Wind Energy Cost Modeling Installation and Decommissioning

    CERN Document Server

    Kaiser, Mark J

    2012-01-01

    Offshore wind energy is one of the most promising and fastest growing alternative energy sources in the world. Offshore Wind Energy Cost Modeling provides a methodological framework to assess installation and decommissioning costs, and using examples from the European experience, provides a broad review of existing processes and systems used in the offshore wind industry. Offshore Wind Energy Cost Modeling provides a step-by-step guide to modeling costs over four sections. These sections cover: ·Background and introductory material, ·Installation processes and vessel requirements, ·Installation cost estimation, and ·Decommissioning methods and cost estimation.  This self-contained and detailed treatment of the key principles in offshore wind development is supported throughout by visual aids and data tables. Offshore Wind Energy Cost Modeling is a key resource for anyone interested in the offshore wind industry, particularly those interested in the technical and economic aspects of installation and decom...

  5. Positronium lifetime in polymers

    CERN Document Server

    Camacho, Abel

    2004-01-01

    A model describing the relationship between the ortho--positronium lifetime and the volume of a void, located in a synthetic zeolite, is analyzed. Our idea, which allows us to take into account the effects of temperature, comprises the introduction of a non--hermitian term in the Hamiltonian, which accounts for the annihilation of the ortho--positronium. The predictions of the present model are also confronted against an already known experimental result.

  6. Multivariable parametric cost model for space and ground telescopes

    Science.gov (United States)

    Stahl, H. Philip; Henrichs, Todd

    2016-09-01

    Parametric cost models can be used by designers and project managers to perform relative cost comparisons between major architectural cost drivers and allow high-level design trades; enable cost-benefit analysis for technology development investment; and, provide a basis for estimating total project cost between related concepts. This paper hypothesizes a single model, based on published models and engineering intuition, for both ground and space telescopes: OTA Cost (X) D (1.75 +/- 0.05) λ (-0.5 +/- 0.25) T-0.25 e (-0.04) Y Specific findings include: space telescopes cost 50X to 100X more ground telescopes; diameter is the most important CER; cost is reduced by approximately 50% every 20 years (presumably because of technology advance and process improvements); and, for space telescopes, cost associated with wavelength performance is balanced by cost associated with operating temperature. Finally, duplication only reduces cost for the manufacture of identical systems (i.e. multiple aperture sparse arrays or interferometers). And, while duplication does reduce the cost of manufacturing the mirrors of segmented primary mirror, this cost savings does not appear to manifest itself in the final primary mirror assembly (presumably because the structure for a segmented mirror is more complicated than for a monolithic mirror).

  7. A Lifetime Prediction Method for LEDs Considering Real Mission Profiles

    DEFF Research Database (Denmark)

    Qu, Xiaohui; Wang, Huai; Zhan, Xiaoqing

    2017-01-01

    The Light-Emitting Diode (LED) has become a very promising alternative lighting source with the advantages of longer lifetime and higher efficiency than traditional ones. The lifetime prediction of LEDs is important to guide the LED system designers to fulfill the design specifications...... and to benchmark the cost-competitiveness of different lighting technologies. However, the existing lifetime data released by LED manufacturers or standard organizations are usually applicable only for some specific temperature and current levels. Significant lifetime discrepancies may be seen in the field...... properties of the life data available from accelerated degradation testing. The electrical and thermal characteristics of LEDs are measured by a T3Ster system, used for the electro-thermal modeling. It also identifies key variables (e.g., heat sink parameters) that can be designed to achieve a specified...

  8. Virtual Reference, Real Money: Modeling Costs in Virtual Reference Services

    Science.gov (United States)

    Eakin, Lori; Pomerantz, Jeffrey

    2009-01-01

    Libraries nationwide are in yet another phase of belt tightening. Without an understanding of the economic factors that influence library operations, however, controlling costs and performing cost-benefit analyses on services is difficult. This paper describes a project to develop a cost model for collaborative virtual reference services. This…

  9. A cost modelling system for cloud computing

    OpenAIRE

    Ajeh, Daniel; Ellman, Jeremy; Keogh, Shelagh

    2014-01-01

    An advance in technology unlocks new opportunities for organizations to increase their productivity, efficiency and process automation while reducing the cost of doing business as well. The emergence of cloud computing addresses these prospects through the provision of agile systems that are scalable, flexible and reliable as well as cost effective. Cloud computing has made hosting and deployment of computing resources cheaper and easier with no up-front charges but pay per-use flexible payme...

  10. Cost-effectiveness of a hypertension management programme in an elderly population: a Markov model

    Directory of Open Access Journals (Sweden)

    Figar Silvana

    2011-04-01

    Full Text Available Abstract Background Mounting evidence shows that multi-intervention programmes for hypertension treatment are more effective than an isolated pharmacological strategy. Full economic evaluations of hypertension management programmes are scarce and contain methodological limitations. The aim of the study was to evaluate if a hypertension management programme for elderly patients is cost-effective compared to usual care from the perspective of a third-party payer. Methods We built a cost-effectiveness model using published evidence of effectiveness of a comprehensive hypertension programme vs. usual care for patients 65 years or older at a community hospital in Buenos Aires, Argentina. We explored incremental cost-effectiveness between groups. The model used a life-time framework adopting a third-party payer's perspective. Incremental cost-effectiveness ratio (ICER was calculated in International Dollars per life-year gained. We performed a probabilistic sensitivity analysis (PSA to explore variable uncertainty. Results The ICER for the base-case of the "Hypertension Programme" versus the "Usual care" approach was 1,124 International Dollars per life-year gained. PSA did not significantly influence results. The programme had a probability of 43% of being dominant (more effective and less costly and, overall, 95% chance of being cost-effective. Discussion Results showed that "Hypertension Programme" had high probabilities of being cost-effective under a wide range of scenarios. This is the first sound cost-effectiveness study to assess a comprehensive hypertension programme versus usual care. This study measures hard outcomes and explores robustness through a probabilistic sensitivity analysis. Conclusions The comprehensive hypertension programme had high probabilities of being cost-effective versus usual care. This study supports the idea that similar programmes could be the preferred strategy in countries and within health care systems where

  11. SUPPLIES COSTS: AN EXPLORATORY STUDY WITH APPLICATION OF MEASUREMENT MODEL OF LOGISTICS COSTS

    Directory of Open Access Journals (Sweden)

    Ana Paula Ferreira Alves

    2013-12-01

    Full Text Available One of the main reasons for the difficulty in adopting an integrated method of calculation of logistics costs is still a lack of adequate information about costs. The management of the supply chain and identify its costs can provide information for their managers, with regard to decision making, generating competitive advantage. Some models of calculating logistics costs are proposed by Uelze (1974, Dias (1996, Goldratt (2002, Christopher (2007, Castiglioni (2009 and Borba & Gibbon (2009, with little disclosure of the results. In this context, this study aims to evaluate the costs of supplies, applying a measurement model of logistics costs. Methodologically, the study characterized as exploratory. The model applied pointed, in original condition, that about R$ 2.5 million were being applied in the process of management of supplies, with replacement costs and storage imbalance. Upgrading the company's data, it is possible obtain a 52% reduction in costs to replace and store supplies. Thus, the cost model applied to logistical supplies showed feasibility of implementation, as well as providing information to assist in management and decision-making in logistics supply.

  12. Process-Improvement Cost Model for the Emergency Department.

    Science.gov (United States)

    Dyas, Sheila R; Greenfield, Eric; Messimer, Sherri; Thotakura, Swati; Gholston, Sampson; Doughty, Tracy; Hays, Mary; Ivey, Richard; Spalding, Joseph; Phillips, Robin

    2015-01-01

    The objective of this report is to present a simplified, activity-based costing approach for hospital emergency departments (EDs) to use with Lean Six Sigma cost-benefit analyses. The cost model complexity is reduced by removing diagnostic and condition-specific costs, thereby revealing the underlying process activities' cost inefficiencies. Examples are provided for evaluating the cost savings from reducing discharge delays and the cost impact of keeping patients in the ED (boarding) after the decision to admit has been made. The process-improvement cost model provides a needed tool in selecting, prioritizing, and validating Lean process-improvement projects in the ED and other areas of patient care that involve multiple dissimilar diagnoses.

  13. Construction Cost Prediction by Using Building Information Modeling

    National Research Council Canada - National Science Library

    Remon F. Aziz

    2015-01-01

    The increased interest in using Building Information Modeling (BIM) in detailed construction cost estimates calls for methodologies to evaluate the effectiveness of BIM-Assisted Detailed Estimating (BADE...

  14. Predicting the lifetime of organic vapor cartridges exposed to volatile organic compound mixtures using a partial differential equations model.

    Science.gov (United States)

    Vuong, François; Chauveau, Romain; Grevillot, Georges; Marsteau, Stéphanie; Silvente, Eric; Vallieres, Cécile

    2016-09-01

    In this study, equilibria, breakthrough curves, and breakthrough times were predicted for three binary mixtures of four volatile organic compounds (VOCs) using a model based on partial differential equations of dynamic adsorption coupling a mass balance, a simple Linear Driving Force (LDF) hypothesis to describe the kinetics, and the well-known Extended-Langmuir (EL) equilibrium model. The model aims to predict with a limited complexity, the BTCs of respirator cartridges exposed to binary vapor mixtures from equilibria and kinetics data obtained from single component. In the model, multicomponent mass transfer was simplified to use only single dynamic adsorption data. The EL expression used in this study predicted equilibria with relatively good accuracy for acetone/ethanol and ethanol/cyclohexane mixtures, but the prediction of cyclohexane uptake when mixed with heptane is less satisfactory. The BTCs given by the model were compared to experimental BTCs to determine the accuracy of the model and the impact of the approximation on mass transfer coefficients. From BTCs, breakthrough times at 10% of the exposure concentration t10% were determined. All t10% were predicted within 20% of the experimental values, and 63% of the breakthrough times were predicted within a 10% error. This study demonstrated that a simple mass balance combined with kinetic approximations is sufficient to predict lifetime for respirator cartridges exposed to VOC mixtures. It also showed that a commonly adopted approach to describe multicomponent adsorption based on volatility of VOC rather than adsorption equilibrium greatly overestimated the breakthrough times.

  15. SOLID OXIDE FUEL CELL MANUFACTURING COST MODEL: SIMULATING RELATIONSHIPS BETWEEN PERFORMANCE, MANUFACTURING, AND COST OF PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Eric J. Carlson; Yong Yang; Chandler Fulton

    2004-04-20

    The successful commercialization of fuel cells will depend on the achievement of competitive system costs and efficiencies. System cost directly impacts the capital equipment component of cost of electricity (COE) and is a major contributor to the O and M component. The replacement costs for equipment (also heavily influenced by stack life) is generally a major contributor to O and M costs. In this project, they worked with the SECA industrial teams to estimate the impact of general manufacturing issues of interest on stack cost using an activities-based cost model for anode-supported planar SOFC stacks with metallic interconnects. An earlier model developed for NETL for anode supported planar SOFCs was enhanced by a linkage to a performance/thermal/mechanical model, by addition of Quality Control steps to the process flow with specific characterization methods, and by assessment of economies of scale. The 3-dimensional adiabatic performance model was used to calculate the average power density for the assumed geometry and operating conditions (i.e., inlet and exhaust temperatures, utilization, and fuel composition) based on publicly available polarizations curves. The SECA team provided guidance on what manufacturing and design issues should be assessed in this Phase I demonstration of cost modeling capabilities. They considered the impact of the following parameters on yield and cost: layer thickness (i.e., anode, electrolyte, and cathode) on cost and stress levels, statistical nature of ceramic material failure on yield, and Quality Control steps and strategies. In this demonstration of the capabilities of the linked model, only the active stack (i.e., anode, electrolyte, and cathode) and interconnect materials were included in the analysis. Factory costs are presented on an area and kilowatt basis to allow developers to extrapolate to their level of performance, stack design, materials, seal and system configurations, and internal corporate overheads and margin

  16. The shift of prompt critical in reflected reactors and the limitations of the mean prompt-neutron lifetime model

    Energy Technology Data Exchange (ETDEWEB)

    Spriggs, G.D. [Los Alamos National Lab., NM (United States); Busch, R.D. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering

    1994-08-01

    Prompt critical in a bare reactor is defined as the point at which the reactivity {rho} of the reactor is equal to the effective delayed neutron fraction {beta}. In a reflected reactor, however, it is shown that prompt critical will occur at a reactivity of {rho} = {beta}(1-f) where f is the fraction of core neutrons that return to the core region after having leaked into the reflector. Furthermore, it is also shown that the mean prompt-neutron lifetime model that has been traditionally used to characterize the dynamic response of reflected reactors may not always provide an adequate representation of the system for reactivities greater than 1$. And finally, the coupled, point-kinetic equations proposed by Avery and further developed by Cohn for simple reflected systems are recast into a more usable form that can be readily used to perform superprompt critical transient analyses.

  17. Comparison between cylindrical and prismatic lithium-ion cell costs using a process based cost model

    Science.gov (United States)

    Ciez, Rebecca E.; Whitacre, J. F.

    2017-02-01

    The relative size and age of the US electric vehicle market means that a few vehicles are able to drive market-wide trends in the battery chemistries and cell formats on the road today. Three lithium-ion chemistries account for nearly all of the storage capacity, and half of the cells are cylindrical. However, no specific model exists to examine the costs of manufacturing these cylindrical cells. Here we present a process-based cost model tailored to the cylindrical lithium-ion cells currently used in the EV market. We examine the costs for varied cell dimensions, electrode thicknesses, chemistries, and production volumes. Although cost savings are possible from increasing cell dimensions and electrode thicknesses, economies of scale have already been reached, and future cost reductions from increased production volumes are minimal. Prismatic cells, which are able to further capitalize on the cost reduction from larger formats, can offer further reductions than those possible for cylindrical cells.

  18. Modelling the Cost and Quality of Preservation Imaging and Archiving

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad

    2009-01-01

    materials held by national cultural heritage institutions in Denmark, a study was undertaken to provide a generic cost model for digital preservation. The outcome of the study is an activity based cost model, which accounts for full economic costs. It is structured around the functional descriptions...... investigated and specifications based on best practice and testing established. Also, the image quality parameters, which influence the long term preservation costs, were identified. In addition, the suitability for preservation of different image file formats and compression algorithms was evaluated...... in the OAIS Reference Model. The cost model divides the OAIS functions in a hierarchy of cost critical activities and measurable components, which are implemented as formulas in a spreadsheet. So far the model has only been completed for activities relating to preservation planning and digital migrations...

  19. A two-part model for censored medical cost data.

    Science.gov (United States)

    Tian, Lu; Huang, Jie

    2007-10-15

    The two-part model is often used to analyse medical cost data which contain a large proportion of zero cost and are highly skewed with some large costs. The total medical costs over a period of time are often censored due to incomplete follow-up, making the analysis difficult as the censoring can be informative. We propose to apply the inverse probability weighting method on a two-part model to analyse right-censored cumulative medical costs with informative censoring. We also introduce a set of simple functionals based on the intermediate cost history to be applied with the efficiency augmentation technique. In addition, we propose a practical model-checking technique based on the cumulative residuals. Simulation studies are conducted to evaluate the finite sample performance of the proposed method. We use a data set on the cardiovascular disease (CVD)-related Medicare costs to illustrate our proposed method.

  20. A comparison of linear demographic models and fraction of lifetime egg production for assessing sustainability in sharks.

    Science.gov (United States)

    Chapple, Taylor K; Botsford, Louis W

    2013-06-01

    Conventional methods for management of data-rich fisheries maintain sustainable populations by assuring that lifetime reproduction is adequate for individuals to replace themselves and accounting for density-dependent recruitment. Fishing is not allowed to reduce relative lifetime reproduction, the fraction of current egg production relative to unfished egg production (FLEP), below a sustainable level. Because most shark fisheries are data poor, other representations of persistence status have been used, including linear demographic models, which incorporate life-history characteristics in age-structured models with no density dependence. We tested how well measures of sustainability from 3 linear demographic methods (rebound potential, stochastic growth rate, and potential population increase) reflect actual population persistence by comparing values of these measures with FLEP for 26 shark species. We also calculated the value of fishing mortality (F) that would allow all 26 species to maintain an accepted precautionary threshold for sharks of FLEP = 60%, expressing F as a fraction of natural mortality (M). Values of stochastic growth rate and potential population growth did not covary in rank order with FLEP (p = 0.057 and p = 0.077, respectively) and neither was significantly correlated with FLEP. Ordinal ranking of rebound potential positively covaried with FLEP (p = 0.00013), but the relative rankings of some species were substantially out of order. Adopting a sustainable limit of F = 0.16M would maintain all 26 species above the precautionary minimum value of FLEP (60%). We concluded that shark-fishery and conservation policies should rely on calculation of replacement (i.e., FLEP), and that sharks should be fished at a precautionary level that would protect all stocks (i.e., F< 0.16M).

  1. Constellation Program Life-cycle Cost Analysis Model (LCAM)

    Science.gov (United States)

    Prince, Andy; Rose, Heidi; Wood, James

    2008-01-01

    The Constellation Program (CxP) is NASA's effort to replace the Space Shuttle, return humans to the moon, and prepare for a human mission to Mars. The major elements of the Constellation Lunar sortie design reference mission architecture are shown. Unlike the Apollo Program of the 1960's, affordability is a major concern of United States policy makers and NASA management. To measure Constellation affordability, a total ownership cost life-cycle parametric cost estimating capability is required. This capability is being developed by the Constellation Systems Engineering and Integration (SE&I) Directorate, and is called the Lifecycle Cost Analysis Model (LCAM). The requirements for LCAM are based on the need to have a parametric estimating capability in order to do top-level program analysis, evaluate design alternatives, and explore options for future systems. By estimating the total cost of ownership within the context of the planned Constellation budget, LCAM can provide Program and NASA management with the cost data necessary to identify the most affordable alternatives. LCAM is also a key component of the Integrated Program Model (IPM), an SE&I developed capability that combines parametric sizing tools with cost, schedule, and risk models to perform program analysis. LCAM is used in the generation of cost estimates for system level trades and analyses. It draws upon the legacy of previous architecture level cost models, such as the Exploration Systems Mission Directorate (ESMD) Architecture Cost Model (ARCOM) developed for Simulation Based Acquisition (SBA), and ATLAS. LCAM is used to support requirements and design trade studies by calculating changes in cost relative to a baseline option cost. Estimated costs are generally low fidelity to accommodate available input data and available cost estimating relationships (CERs). LCAM is capable of interfacing with the Integrated Program Model to provide the cost estimating capability for that suite of tools.

  2. A comparison of NEAR actual spacecraft costs with three parametric cost models

    Science.gov (United States)

    Mosher, Todd J.; Lao, Norman Y.; Davalos, Evelyn T.; Bearden, David A.

    1999-11-01

    Costs for modern (post-1990) U.S.-built small planetary spacecraft have been shown to exhibit significantly different trends from those of larger spacecraft. These differences cannot be accounted for simply by the change in size alone. Some have attributed this departure to NASA's "faster, better, cheaper" design approach embodied by the efficiency of smaller teams, reduced government oversight, increased focus on cost, and short development periods. With the Discovery, Mars Surveyor and New Millennium programs representing the new approach to planetary exploration, it is important to understand these current cost trends and to be able to estimate costs of future proposed missions. To address this issue, The Aerospace Corporation (hereafter referred to as Aerospace) performed a study to compare the actual costs of the Near Earth Asteroid Rendezvous (NEAR) spacecraft bus (instruments were not estimated) using three different cost models; the U.S. Air Force Unmanned Spacecraft Cost Model, Version 7 (USCM-7), the Science Applications International Corporation (SAIC) NASA/Air Force Cost Model 1996 (NAFCOM96) and The Aerospace Corporation's Small Satellite Cost Model 1998 (SSCM98). The NEAR spacecraft was chosen for comparison because it was the first Discovery mission launched, and recently recognized with a Laurel award by Aviation Week and Space Technology as a benchmark for NASA's Discovery program [North, 1997]. It was also selected because the cost data has been released into the public domain [Hemmings, 1996]which makes it easy to discuss in a public forum. This paper summarizes the NEAR program, provides a short synopsis of each of the three cost models, and demonstrates how they were applied for this study.

  3. Why do general circulation models overestimate the aerosol cloud lifetime effect? A case study comparing CAM5 and a CRM

    Science.gov (United States)

    Zhou, Cheng; Penner, Joyce E.

    2017-01-01

    Observation-based studies have shown that the aerosol cloud lifetime effect or the increase of cloud liquid water path (LWP) with increased aerosol loading may have been overestimated in climate models. Here, we simulate shallow warm clouds on 27 May 2011 at the southern Great Plains (SGP) measurement site established by the Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) program using a single-column version of a global climate model (Community Atmosphere Model or CAM) and a cloud resolving model (CRM). The LWP simulated by CAM increases substantially with aerosol loading while that in the CRM does not. The increase of LWP in CAM is caused by a large decrease of the autoconversion rate when cloud droplet number increases. In the CRM, the autoconversion rate is also reduced, but this is offset or even outweighed by the increased evaporation of cloud droplets near the cloud top, resulting in an overall decrease in LWP. Our results suggest that climate models need to include the dependence of cloud top growth and the evaporation/condensation process on cloud droplet number concentrations.

  4. Expectation Maximization Algorithm for Box-Cox Transformation Cure Rate Model and Assessment of Model Mis-specication under Weibull Lifetimes.

    Science.gov (United States)

    Pal, Suvra; Balakrishnan, N

    2017-05-16

    In this paper, we develop likelihood inference based on the expectation maximization (EM) algorithm for the Box- Cox transformation cure rate model assuming the lifetimes to follow a Weibull distribution. A simulation study is carried out to demonstrate the performance of the proposed estimation method. Through Monte Carlo simulations, we also study the effect of model mis-specification on the estimate of cure rate. Finally, we analyze a well-known data on melanoma with the model and the inferential method developed here.

  5. Sulfate geoengineering impact on methane transport and lifetime: results from the Geoengineering Model Intercomparison Project (GeoMIP)

    Science.gov (United States)

    Visioni, Daniele; Pitari, Giovanni; Aquila, Valentina; Tilmes, Simone; Cionni, Irene; Di Genova, Glauco; Mancini, Eva

    2017-09-01

    Sulfate geoengineering (SG), made by sustained injection of SO2 in the tropical lower stratosphere, may impact the CH4 abundance through several photochemical mechanisms affecting tropospheric OH and hence the methane lifetime. (a) The reflection of incoming solar radiation increases the planetary albedo and cools the surface, with a tropospheric H2O decrease. (b) The tropospheric UV budget is upset by the additional aerosol scattering and stratospheric ozone changes: the net effect is meridionally not uniform, with a net decrease in the tropics, thus producing less tropospheric O(1D). (c) The extratropical downwelling motion from the lower stratosphere tends to increase the sulfate aerosol surface area density available for heterogeneous chemical reactions in the mid-to-upper troposphere, thus reducing the amount of NOx and O3 production. (d) The tropical lower stratosphere is warmed by solar and planetary radiation absorption by the aerosols. The heating rate perturbation is highly latitude dependent, producing a stronger meridional component of the Brewer-Dobson circulation. The net effect on tropospheric OH due to the enhanced stratosphere-troposphere exchange may be positive or negative depending on the net result of different superimposed species perturbations (CH4, NOy, O3, SO4) in the extratropical upper troposphere and lower stratosphere (UTLS). In addition, the atmospheric stabilization resulting from the tropospheric cooling and lower stratospheric warming favors an additional decrease of the UTLS extratropical CH4 by lowering the horizontal eddy mixing. Two climate-chemistry coupled models are used to explore the above radiative, chemical and dynamical mechanisms affecting CH4 transport and lifetime (ULAQ-CCM and GEOSCCM). The CH4 lifetime may become significantly longer (by approximately 16 %) with a sustained injection of 8 Tg-SO2 yr-1 starting in the year 2020, which implies an increase of tropospheric CH4 (200 ppbv) and a positive indirect radiative

  6. Maintenance Policy for Multi-Component System with Fuzzy Lifetimes

    Institute of Scientific and Technical Information of China (English)

    赵瑞清; 高金伍

    2003-01-01

    The application of possibility theory to maintenance policies is proposed in this paper. The lifetime of a component is modeled as a fuzzy variable. Two types of replacement policies-block replacement and age replacement with fuzzy lifetimes are investigated. The theorems show that the long-run average fuzzy reward per unit time in both policies is just the expected cost per unit of time. In order to solve the proposed models, a hybrid intelligent algorithm is employed. Finally, numerical examples are provided for the sake of illustration.

  7. Evaluation of Cost Models and Needs & Gaps Analysis

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad

    2014-01-01

    his report ’D3.1—Evaluation of Cost Models and Needs & Gaps Analysis’ provides an analysis of existing research related to the economics of digital curation and cost & benefit modelling. It reports upon the investigation of how well current models and tools meet stakeholders’ needs for calculating...... for amore efficient use of resources for digital curation. To facilitate and clarify the model evaluation the report first outlines a basic terminology and a generaldescription of the characteristics of cost and benefit models.The report then describes how the ten current and emerging cost and benefit...... they breakdown costs. This is followed by an in depth analysis of stakeholders’ needs for financial information derived from the 4C project stakeholder consultation.The stakeholders’ needs analysis indicated that models should:• support accounting, but more importantly they should enable budgeting• be able...

  8. The role of information in a lifetime process - a model of weight maintenance by women over long time periods

    Directory of Open Access Journals (Sweden)

    Judit Bar-Ilan

    2006-01-01

    Full Text Available Introduction. This paper proposes a model of information behaviour of women during their life-long struggle to maintain normal weight. Method. The model is integrative and contextual, built on existing models in information science and several other disciplines, and the life stories of about fifty Israeli women aged 25-55 and interviews with professionals. Analysis. The life stories of the participating women were analyzed qualitatively, major themes and phases were identified. Results. Weight loss and/or maintenance behaviour is a lifetime process in which distinctive stages were identified. In most cases the weight gain - weight loss - maintenance cycle is a recurring cycle. Information is a major resource during the process: several roles of information were defined: enabling, motivating, reinforcing, providing background information related to weight problems and creating the internal cognitive schema related to food and weight. Information behaviour and the roles of information vary with the different stages. Information needs are also influenced by the specific stage of the process. Information gathered at previous cycles is reused, and information gained through previous experience effects behaviour in the current cycle. Conclusion. The model has both theoretical and practical implications.

  9. The Impact of Current CH4 and N2O Loss Process Uncertainties on Model Calculated Ozone and Global Lifetimes

    Science.gov (United States)

    Fleming, E. L.; Burkholder, J. B.; Kurylo, M. J., III; Jackman, C. H.

    2015-12-01

    The atmospheric loss processes of CH4 and N2O, their estimated uncertainties, lifetimes, and impacts on ozone abundance and long-term trends are examined using atmospheric model calculations and updated kinetic and photochemical parameters and uncertainty factors from SPARC (2013). Uncertainties in CH4 loss due to reaction with OH and O(1D) have relatively small impacts on present day calculated global total ozone (±0.2-0.3%), with the OH+CH4 uncertainty impacting tropospheric ozone by ±3-5%. Uncertainty in the Cl+CH4 reaction affects the amount of chlorine in radical vs. reservoir forms and has a modest impact on present day SH polar ozone (~±6%), and on the rate of past SH polar ozone decline and future recovery. The O(1D)+N2O reaction has uncertainty in both the total rate coefficient and branching ratio for the O2+N2 and 2*NO product channels. This uncertainty results in a substantial range in present day stratospheric odd nitrogen (±10-25%) and global total ozone (±1-2.5%). This uncertainty also impacts the rate of past global total ozone decline and future recovery, with a range in future ozone projections of ±1-1.5% by 2100, relative to present day. The uncertainty ranges in calculated CH4 and N2O global lifetimes are also examined: these ranges are significantly reduced when using the updated SPARC estimated uncertainties compared with those from JPL-2010.

  10. A Costing Model for Non Traditional Education.

    Science.gov (United States)

    Knodle, L. L.

    To facilitate college and university officials in financing the eduational needs of the nontraditional students, a method for collecting and determining the cost of providing units of instruction through various delivery mechanisms available to colleges and universities is presented. Twelve ways of delivering instructional units, eight types of…

  11. Cost modelling as decision support when locating manufacturing facilities

    Directory of Open Access Journals (Sweden)

    Christina Windmark

    2016-01-01

    Full Text Available This paper presents a methodology for cost estimation in developing decision supports for production location issues. The purpose is to provide a structured work procedure to be used by practitioners to derive the knowledge needed to make informed decisions on where to locate production. This paper present a special focus on how to integrate cost effects during the decision process. The work procedure and cost models were developed in close collaboration with a group of industrial partners. The result is a structure of cost estimation tools aligned to different steps in the work procedure. The cost models can facilitate both cost estimation for manufacturing a product under new preconditions, including support costs, and cost simulations to analyse the risks of wrong estimations and uncertainties in the input parameters. Future research aims to test the methodology in ongoing transfer projects to further understand difficulties in managing global production systems. In existing models and methods presented in the literature, cost is usually estimated on a too aggregated level to be suitable for decision support regarding production system design. The cost estimation methodology presented here provides new insights on cost driving factors related to the production system.

  12. Expectation maximization-based likelihood inference for flexible cure rate models with Weibull lifetimes.

    Science.gov (United States)

    Balakrishnan, Narayanaswamy; Pal, Suvra

    2016-08-01

    Recently, a flexible cure rate survival model has been developed by assuming the number of competing causes of the event of interest to follow the Conway-Maxwell-Poisson distribution. This model includes some of the well-known cure rate models discussed in the literature as special cases. Data obtained from cancer clinical trials are often right censored and expectation maximization algorithm can be used in this case to efficiently estimate the model parameters based on right censored data. In this paper, we consider the competing cause scenario and assuming the time-to-event to follow the Weibull distribution, we derive the necessary steps of the expectation maximization algorithm for estimating the parameters of different cure rate survival models. The standard errors of the maximum likelihood estimates are obtained by inverting the observed information matrix. The method of inference developed here is examined by means of an extensive Monte Carlo simulation study. Finally, we illustrate the proposed methodology with a real data on cancer recurrence.

  13. Activity-Based Costing Model for Assessing Economic Performance.

    Science.gov (United States)

    DeHayes, Daniel W.; Lovrinic, Joseph G.

    1994-01-01

    An economic model for evaluating the cost performance of academic and administrative programs in higher education is described. Examples from its application at Indiana University-Purdue University Indianapolis are used to illustrate how the model has been used to control costs and reengineer processes. (Author/MSE)

  14. A Cost-of-Quality Model at El Camino College.

    Science.gov (United States)

    Miller, Timothy D.

    1994-01-01

    This article describes the cost-of-quality model used at El Camino College (California), which formally measures the costs associated with process improvement activities. A case study illustrates use of the model in evaluating a new process for reimbursing faculty and staff attending conferences. (DB)

  15. Process Cost Modeling for Multi-Disciplinary Design Optimization

    Science.gov (United States)

    Bao, Han P.; Freeman, William (Technical Monitor)

    2002-01-01

    For early design concepts, the conventional approach to cost is normally some kind of parametric weight-based cost model. There is now ample evidence that this approach can be misleading and inaccurate. By the nature of its development, a parametric cost model requires historical data and is valid only if the new design is analogous to those for which the model was derived. Advanced aerospace vehicles have no historical production data and are nowhere near the vehicles of the past. Using an existing weight-based cost model would only lead to errors and distortions of the true production cost. This report outlines the development of a process-based cost model in which the physical elements of the vehicle are costed according to a first-order dynamics model. This theoretical cost model, first advocated by early work at MIT, has been expanded to cover the basic structures of an advanced aerospace vehicle. Elemental costs based on the geometry of the design can be summed up to provide an overall estimation of the total production cost for a design configuration. This capability to directly link any design configuration to realistic cost estimation is a key requirement for high payoff MDO problems. Another important consideration in this report is the handling of part or product complexity. Here the concept of cost modulus is introduced to take into account variability due to different materials, sizes, shapes, precision of fabrication, and equipment requirements. The most important implication of the development of the proposed process-based cost model is that different design configurations can now be quickly related to their cost estimates in a seamless calculation process easily implemented on any spreadsheet tool. In successive sections, the report addresses the issues of cost modeling as follows. First, an introduction is presented to provide the background for the research work. Next, a quick review of cost estimation techniques is made with the intention to

  16. Operations and support cost modeling using Markov chains

    Science.gov (United States)

    Unal, Resit

    1989-01-01

    Systems for future missions will be selected with life cycle costs (LCC) as a primary evaluation criterion. This reflects the current realization that only systems which are considered affordable will be built in the future due to the national budget constaints. Such an environment calls for innovative cost modeling techniques which address all of the phases a space system goes through during its life cycle, namely: design and development, fabrication, operations and support; and retirement. A significant portion of the LCC for reusable systems are generated during the operations and support phase (OS). Typically, OS costs can account for 60 to 80 percent of the total LCC. Clearly, OS costs are wholly determined or at least strongly influenced by decisions made during the design and development phases of the project. As a result OS costs need to be considered and estimated early in the conceptual phase. To be effective, an OS cost estimating model needs to account for actual instead of ideal processes by associating cost elements with probabilities. One approach that may be suitable for OS cost modeling is the use of the Markov Chain Process. Markov chains are an important method of probabilistic analysis for operations research analysts but they are rarely used for life cycle cost analysis. This research effort evaluates the use of Markov Chains in LCC analysis by developing OS cost model for a hypothetical reusable space transportation vehicle (HSTV) and suggests further uses of the Markov Chain process as a design-aid tool.

  17. Fixed transaction costs and modelling limited dependent variables

    NARCIS (Netherlands)

    Hempenius, A.L.

    1994-01-01

    As an alternative to the Tobit model, for vectors of limited dependent variables, I suggest a model, which follows from explicitly using fixed costs, if appropriate of course, in the utility function of the decision-maker.

  18. A software cost model with maintenance and risk costs for safety-critical systems

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-wei; YANG Xiao-zong; QU Feng; DONG Jian

    2006-01-01

    According to the consequences of software failures, software faults remaining in safety-critical systems can be classified into two sets: common faults and fatal faults. Common faults cause slight loss when they are activated. A fatal fault can lead to significant loss, and even damage the safety-critical system entirely when it is activated. A software reliability growth model for safety-critical systems is developed based on G-O model. And a software cost model is proposed too. The cost model considers maintenance and risk costs due to software failures. The optimal release policies are discussed to minimize the total software cost. A numerical example is provided to illustrate how to use the results we obtained.

  19. New Detectors to Explore the Lifetime Frontier

    CERN Document Server

    Chou, John Paul; Lubatti, H J

    2016-01-01

    Long-lived particles (LLPs) are a common feature in many beyond the Standard Model theories, including supersymmetry, and are generically produced in exotic Higgs decays. Unfortunately, no existing or proposed search strategy will be able to probe neutral LLPs with lifetimes near the limit set by Big Bang Nucleosynthesis (BBN), $c \\tau \\lesssim 10^7 - 10^8$ m. We propose the MATHUSLA surface detector concept (MAssive Timing Hodoscope for Ultra Stable neutraL pArticles), which can be implemented cost-effectively and in time for the high luminosity LHC upgrade to find such ultra-long-lived particles (ULLPs), whether produced in exotic Higgs decays or more general production modes. We also advocate for a dedicated LLP detector at a future 100 TeV collider, where a modestly sized underground design can discover ULLPs with lifetimes at the BBN limit produced in sub-percent level exotic Higgs decays

  20. Renewable Energy Cost Modeling. A Toolkit for Establishing Cost-Based Incentives in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Gifford, Jason S. [Sustainable Energy Advantage, LLC, Framington, MA (United States); Grace, Robert C. [Sustainable Energy Advantage, LLC, Framington, MA (United States); Rickerson, Wilson H. [Meister Consultants Group, Inc., Boston, MA (United States)

    2011-05-01

    This report serves as a resource for policymakers who wish to learn more about levelized cost of energy (LCOE) calculations, including cost-based incentives. The report identifies key renewable energy cost modeling options, highlights the policy implications of choosing one approach over the other, and presents recommendations on the optimal characteristics of a model to calculate rates for cost-based incentives, FITs, or similar policies. These recommendations shaped the design of NREL's Cost of Renewable Energy Spreadsheet Tool (CREST), which is used by state policymakers, regulators, utilities, developers, and other stakeholders to assist with analyses of policy and renewable energy incentive payment structures. Authored by Jason S. Gifford and Robert C. Grace of Sustainable Energy Advantage LLC and Wilson H. Rickerson of Meister Consultants Group, Inc.

  1. Improved methodology for developing cost uncertainty models for naval vessels

    OpenAIRE

    Brown, Cinda L.

    2008-01-01

    The purpose of this thesis is to analyze the probabilistic cost model currently in use by NAVSEA 05C to predict cost uncertainty in naval vessel construction and to develop a method that better predicts the ultimate cost risk. The data used to develop the improved approach is collected from analysis of the CG(X) class ship by NAVSEA 05C. The NAVSEA 05C cost risk factors are reviewed and analyzed to determine if different factors are better cost predictors. The impact of data elicitation, t...

  2. An upgraded drift–diffusion model for evaluating the carrier lifetimes in radiation-damaged semiconductor detectors

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Lopez, J., E-mail: fjgl@us.es [Dept of Atomic, Molecular and Nuclear Physics, University of Sevilla, Av. Reina Mercedes s/n, 41012 Sevilla (Spain); CNA (U. Sevilla, J. Andalucia, CSIC), Av. Thomas A. Edison 7, 41092 Sevilla (Spain); Jimenez-Ramos, M.C.; Rodriguez-Ramos, M. [CNA (U. Sevilla, J. Andalucia, CSIC), Av. Thomas A. Edison 7, 41092 Sevilla (Spain); Forneris, J. [Physics Dept./NIS Centre, University of Torino, INFN-Sez. di Torino, via P. Giuria 1, 10125 Torino (Italy); Ceballos, J. [Institute of Microelectronics of Seville, IMSE-CNM (CSIC/University of Seville), Seville 41092 (Spain)

    2016-03-15

    The transport properties of a series of n- and p-type Si diodes have been studied by the ion beam induced charge (IBIC) technique using a 4 MeV proton microbeam. The samples were irradiated with 17 MeV protons at fluences ranging from 1 × 10{sup 12} to 1 × 10{sup 13} p/cm{sup 2} in order to produce a uniform profile of defects with depth. The analysis of the charge collection efficiency (CCE) as a function of the reverse bias voltage has been carried out using an upgraded drift–diffusion (D–D) model which takes into account the possibility of carrier recombination not only in the neutral substrate, as the simple D–D model assumes, but also within the depletion region. This new approach for calculating the CCE is fundamental when the drift length of carriers cannot be considered as much greater that the thickness of the detector due to the ion induced damage. From our simulations, we have obtained the values of the carrier lifetimes for the pristine and irradiated diodes, which have allowed us to calculate the effective trapping cross sections using the one dimension Shockley–Read–Hall model. The results of our calculations have been compared to the data obtained using a recently developed Monte Carlo code for the simulation of IBIC analysis, based on the probabilistic interpretation of the excess carrier continuity equations.

  3. A theoretical model for attachment lifetimes of kinetochore-microtubules: Mechano-kinetic "catch-bond" mechanism for error-correction

    CERN Document Server

    Shtylla, Blerta

    2013-01-01

    Before cell division, two identical copies of chromosomes are pulled apart by microtubule (MT) filaments that approach the chromosomes from the opposite poles a mitotic spindle. Connection between the MTs and the chromosomes are mediated by a molecular complex called kinetochore. An externally applied tension can lead to detachment of the MTs from the kinetochore; the mean lifetime of such an attachment is essentially a mean first-passage time. In their in-vitro pioneering single-kinetochore experiments, Akiyoshi et al. (Nature 468, 576 (2010)), observed that the mean lifetimes of reconstituted MT-kinetochore attachments vary non-monotonically with increasing tension. The counter-intuitive stabilization of the attachments by small load forces was interpreted in terms of a catch-bond-like mechanism based on a phenomenological 2-state kinetic model. Here we develop the first detailed microscopic model for studying the dependence of the lifetime of the MT-kinetochore attachment on (a) the structure, (b) energeti...

  4. Microstructurally based thermomechanical fatigue lifetime model of solder joints for electronic applications

    Energy Technology Data Exchange (ETDEWEB)

    Frear, D.R.; Rashid, M.M.; Burchett, S.N.

    1993-07-01

    We present a new methodology for predicting the fatigue life of solder joints for electronics applications. This approach involves integration of experimental and computational techniques. The first stage involves correlating the manufacturing and processing parameters with the starting microstructure of the solder joint. The second stage involves a series of experiments that characterize the evolution of the microstructure during thermal cycling. The third stage consists of a computer modeling and simulation effort that utilizes the starting microstructure and experimental data to produce a reliability prediction of the solder joint. This approach is an improvement over current methodologies because it incorporates the microstructure and properties of the solder directly into the model and allows these properties to evolve as the microstructure changes during fatigue.

  5. ESTIMATION MODEL OF RESIDUAL LIFE-TIME OF LOCOMOTIVE FRAME BOGIE WITH ALLOWANCE FOR CREEP

    Directory of Open Access Journals (Sweden)

    V. R. Skalskyi

    2014-12-01

    Full Text Available Purpose. The problem of determining the residual life of frame bogie elements of locomotives is a great importance for predicting their work safely and avoidance potential failures on the track. This especially concern cases when such elements have creep-fatigue cracks which grow under action of cyclic loading with excerpts T1 in the cycle and reach their critical size. Here the question of the propagation of such defects (cracks arises, their kinetics and about the period of subcritical cracks growth. The aim is to develop a calculation model for determination the period of subcritical creep-fatigue cracks growth in the bogies frames of electric locomotive. The model takes into account the basic parameters of load, geometry of the construction element and cracks. Methodology. The calculation model for determination the period of subcritical creep-fatigue cracks growth in structural elements of frame under conditions of variable load time has been formulated. It is based on the first law of thermodynamics concerning to mechanics of solids slow fracture at low temperature creep and variable loadings. It is assumed that the period of unsteady creep dominates here (the first section of the creep curve. Low-temperature creep is creep of materials at temperatures T0 < 0,5Tmp, where Tmp − the melting point of the material. Findings. The analytical formula for the determination of the stress intensity factor of truck bolster with technological hole has been obtained. It is shown that by experimentally established constants of the material using the proposed analytical relations can easily determine residual resource of the bogie frame elements. Originality. The new mathematical model for describing the kinetics of creep-fatigue cracks growth in the frames bogies of electric locomotive under variable in time loadings with various time excerpts and on this base the period determination of subcritical crack growth has been proposed. Practical value

  6. Aircraft Scheduled Airframe Maintenance and Downtime Integrated Cost Model

    Directory of Open Access Journals (Sweden)

    Remzi Saltoğlu

    2016-01-01

    Full Text Available Aviation industry has grown rapidly since the first scheduled commercial aviation started one hundred years ago. There is a fast growth in the number of passengers, routes, and frequencies, with high revenues and low margins, which make this industry one of the most challenging businesses in the world. Every operator aims to undertake the minimum operating cost and gain profit as much as possible. One of the significant elements of operator’s operating cost is the maintenance cost. During maintenance scheduling, operator calculates the maintenance cost that it needs to budget. Previous works show that this calculation includes only costs that are directly related to the maintenance process such as cost of labor, material, and equipment. In some cases, overhead cost is also included. Some of previous works also discuss the existence of another cost throughout aircraft downtime, which is defined as cost of revenue loss. Nevertheless, there is not any standard model that shows how to define and calculate downtime cost. For that reason, the purpose of this paper is to introduce a new model and analysis technique that can be used to calculate aircraft downtime cost due to maintenance.

  7. Systematic review of model-based analyses reporting the cost-effectiveness and cost-utility of cardiovascular disease management programs.

    Science.gov (United States)

    Maru, Shoko; Byrnes, Joshua; Whitty, Jennifer A; Carrington, Melinda J; Stewart, Simon; Scuffham, Paul A

    2015-02-01

    The reported cost effectiveness of cardiovascular disease management programs (CVD-MPs) is highly variable, potentially leading to different funding decisions. This systematic review evaluates published modeled analyses to compare study methods and quality. Articles were included if an incremental cost-effectiveness ratio (ICER) or cost-utility ratio (ICUR) was reported, it is a multi-component intervention designed to manage or prevent a cardiovascular disease condition, and it addressed all domains specified in the American Heart Association Taxonomy for Disease Management. Nine articles (reporting 10 clinical outcomes) were included. Eight cost-utility and two cost-effectiveness analyses targeted hypertension (n=4), coronary heart disease (n=2), coronary heart disease plus stoke (n=1), heart failure (n=2) and hyperlipidemia (n=1). Study perspectives included the healthcare system (n=5), societal and fund holders (n=1), a third party payer (n=3), or was not explicitly stated (n=1). All analyses were modeled based on interventions of one to two years' duration. Time horizon ranged from two years (n=1), 10 years (n=1) and lifetime (n=8). Model structures included Markov model (n=8), 'decision analytic models' (n=1), or was not explicitly stated (n=1). Considerable variation was observed in clinical and economic assumptions and reporting practices. Of all ICERs/ICURs reported, including those of subgroups (n=16), four were above a US$50,000 acceptability threshold, six were below and six were dominant. The majority of CVD-MPs was reported to have favorable economic outcomes, but 25% were at unacceptably high cost for the outcomes. Use of standardized reporting tools should increase transparency and inform what drives the cost-effectiveness of CVD-MPs. © The European Society of Cardiology 2014.

  8. Life Cycle Costing Model for Solid Waste Management

    DEFF Research Database (Denmark)

    Martinez-Sanchez, Veronica; Astrup, Thomas Fruergaard

    2014-01-01

    To ensure sustainability of solid waste management, there is a need for cost assessment models which are consistent with environmental and social assessments. However, there is a current lack of standardized terminology and methodology to evaluate economic performances and this complicates...... LCC, e.g. waste generator, waste operator and public finances and the perspective often defines the systemboundaries of the study, e.g. waste operators often focus on her/his own cost, i.e. technology based,whereas waste generators and public finances often focus on the entire waste system, i.......e. system based. Figure 1 illustrates the proposed modeling framework that distinguishes between: a) budget cost, b) externality costs and 3) transfers and defines unit costs of each technology (per ton of input waste). Unitcosts are afterwards combined with a mass balance to calculate the technology cost...

  9. COST OF QUALITY MODELS AND THEIR IMPLEMENTATION IN MANUFACTURING FIRMS

    Directory of Open Access Journals (Sweden)

    N.M. Vaxevanidis

    2009-03-01

    Full Text Available In order to improve quality, an organization must take into account the costs associated with achieving quality since the objective of continuous improvement programs is not only to meet customer requirements, but also to do it at the lowest, possible, cost. This can only obtained by reducing the costs needed to achieve quality, and the reduction of these costs is only possible if they are identified and measured. Therefore, measuring and reporting the cost of quality (CoQ should be considered an important issue for achieving quality excellence. To collect quality costs an organization needs to adopt a framework to classify costs; however, there is no general agreement on a single broad definition of quality costs. CoQ is usually understood as the sum of conformance plus non-conformance costs, where cost of conformance is the price paid for prevention of poor quality (for example, inspection and quality appraisal and cost of non-conformance is the cost of poor quality caused by product and service failure (for example, rework and returns. The objective of this paper is to give a survey of research articles on the topic of CoQ; it opens with a literature review focused on existing CoQ models; then, it briefly presents the most common CoQ parameters and the metrics (indices used for monitoring CoQ. Finally, the use of CoQ models in practice, i.e., the implementation of a quality costing system and cost of quality reporting in companies is discussed, with emphasis in cases concerning manufacturing firms.

  10. Simulation modeling of outcomes and cost effectiveness.

    Science.gov (United States)

    Ramsey, S D; McIntosh, M; Etzioni, R; Urban, N

    2000-08-01

    Modeling will continue to be used to address important issues in clinical practice and health policy issues that have not been adequately studied with high-quality clinical trials. The apparent ad hoc nature of models belies the methodologic rigor that is applied to create the best models in cancer prevention and care. Models have progressed from simple decision trees to extremely complex microsimulation analyses, yet all are built using a logical process based on objective evaluation of the path between intervention and outcome. The best modelers take great care to justify both the structure and content of the model and then test their assumptions using a comprehensive process of sensitivity analysis and model validation. Like clinical trials, models sometimes produce results that are later found to be invalid as other data become available. When weighing the value of models in health care decision making, it is reasonable to consider the alternatives. In the absence of data, clinical policy decisions are often based on the recommendations of expert opinion panels or on poorly defined notions of the standard of care or medical necessity. Because such decision making rarely entails the rigorous process of data collection, synthesis, and testing that is the core of well-conducted modeling, it is usually not possible for external audiences to examine the assumptions and data that were used to derive the decisions. One of the modeler's most challenging tasks is to make the structure and content of the model transparent to the intended audience. The purpose of this article is to clarify the process of modeling, so that readers of models are more knowledgeable about their uses, strengths, and limitations.

  11. Modelling the full trip costs of urban intermodal passenger transport

    OpenAIRE

    Yeh, Chao-Fu; Papon, Francis

    2011-01-01

    To face the competition of private motorized vehicles, intermodal transport becomes a successful condition to encourage public transport and non-motorized modes and to reasonably control the continual growth of individual motorized vehicles in the city area. Therefore, the objective of this research intends to develop a comparable calculating model combining the private, public and external costs of passenger urban transport networks. Private costs consist in the operational-private costs bor...

  12. New Approaches in Usable Booster System Life Cycle Cost Modeling

    Science.gov (United States)

    2012-01-01

    Lean NPD practices (many) • Lean Production & Operations Practices (many) • Supply Chain Operations Reference ( SCOR ) Model , Best Practices Make Deliver...NEW APPROACHES IN REUSABLE BOOSTER SYSTEM LIFE CYCLE COST MODELING Edgar Zapata National Aeronautics and Space Administration Kennedy Space Center...Kennedy Space Center (KSC) and the Air Force Research Laboratory (AFRL). The work included the creation of a new cost estimating model and an LCC

  13. Lifetime-dependent effects of bisphenol A on asthma development in an experimental mouse model.

    Directory of Open Access Journals (Sweden)

    Susanne Petzold

    Full Text Available BACKGROUND: Environmental factors are thought to contribute significantly to the increase of asthma prevalence in the last two decades. Bisphenol A (BPA is a xenoestrogen commonly used in consumer products and the plastic industry. There is evidence and an ongoing discussion that endocrine disruptors like BPA may affect human health and also exert alterations on in the immune system. The aim of this study was to investigate age-dependent effects of BPA on the asthma risk using a murine model to explain the controversial results reported till date. METHODS: BALB/c mice were exposed to BPA via the drinking water for different time periods including pregnancy and breastfeeding. To induce an asthma phenotype, mice were sensitized to ovalbumin (OVA, followed by an intrapulmonary allergen challenge. RESULTS: BPA exposure during pregnancy and breastfeeding had no significant effect on asthma development in the offspring. In contrast, lifelong exposure from birth until the last antigen challenge clearly increased eosinophilic inflammation in the lung, airway hyperreactivity and antigen-specific serum IgE levels in OVA-sensitized adult mice compared to mice without BPA exposure. Surprisingly, BPA intake during the sensitization period significantly reduced the development of allergic asthma. This effect was reversed in the presence of a glucocorticoid receptor antagonist. CONCLUSIONS: Our results demonstrate that the impact of BPA on asthma risk is strongly age-dependent and ranges from asthma-promoting to asthma-reducing effects. This could explain the diversity of results from previous studies regarding the observed health impact of BPA.

  14. Lifetime-Dependent Effects of Bisphenol A on Asthma Development in an Experimental Mouse Model

    Science.gov (United States)

    Petzold, Susanne; Averbeck, Marco; Simon, Jan C.; Lehmann, Irina; Polte, Tobias

    2014-01-01

    Background Environmental factors are thought to contribute significantly to the increase of asthma prevalence in the last two decades. Bisphenol A (BPA) is a xenoestrogen commonly used in consumer products and the plastic industry. There is evidence and an ongoing discussion that endocrine disruptors like BPA may affect human health and also exert alterations on in the immune system. The aim of this study was to investigate age-dependent effects of BPA on the asthma risk using a murine model to explain the controversial results reported till date. Methods BALB/c mice were exposed to BPA via the drinking water for different time periods including pregnancy and breastfeeding. To induce an asthma phenotype, mice were sensitized to ovalbumin (OVA), followed by an intrapulmonary allergen challenge. Results BPA exposure during pregnancy and breastfeeding had no significant effect on asthma development in the offspring. In contrast, lifelong exposure from birth until the last antigen challenge clearly increased eosinophilic inflammation in the lung, airway hyperreactivity and antigen-specific serum IgE levels in OVA-sensitized adult mice compared to mice without BPA exposure. Surprisingly, BPA intake during the sensitization period significantly reduced the development of allergic asthma. This effect was reversed in the presence of a glucocorticoid receptor antagonist. Conclusions Our results demonstrate that the impact of BPA on asthma risk is strongly age-dependent and ranges from asthma-promoting to asthma-reducing effects. This could explain the diversity of results from previous studies regarding the observed health impact of BPA. PMID:24950052

  15. Manufacturing Cost Levelization Model – A User’s Guide

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, William R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shehabi, Arman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smith, Sarah Josephine [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-08-01

    The Manufacturing Cost Levelization Model is a cost-performance techno-economic model that estimates total large-scale manufacturing costs for necessary to produce a given product. It is designed to provide production cost estimates for technology researchers to help guide technology research and development towards an eventual cost-effective product. The model presented in this user’s guide is generic and can be tailored to the manufacturing of any product, including the generation of electricity (as a product). This flexibility, however, requires the user to develop the processes and process efficiencies that represents a full-scale manufacturing facility. The generic model is comprised of several modules that estimate variable costs (material, labor, and operating), fixed costs (capital & maintenance), financing structures (debt and equity financing), and tax implications (taxable income after equipment and building depreciation, debt interest payments, and expenses) of a notional manufacturing plant. A cash-flow method is used to estimate a selling price necessary for the manufacturing plant to recover its total cost of production. A levelized unit sales price ($ per unit of product) is determined by dividing the net-present value of the manufacturing plant’s expenses ($) by the net present value of its product output. A user defined production schedule drives the cash-flow method that determines the levelized unit price. In addition, an analyst can increase the levelized unit price to include a gross profit margin to estimate a product sales price. This model allows an analyst to understand the effect that any input variables could have on the cost of manufacturing a product. In addition, the tool is able to perform sensitivity analysis, which can be used to identify the key variables and assumptions that have the greatest influence on the levelized costs. This component is intended to help technology researchers focus their research attention on tasks

  16. Business Models for Cost Sharing & Capability Sustainment

    Science.gov (United States)

    2012-08-18

    business models need to adapt in a continuous process in most cases, notably the major platforms and technologies featured in this research. Demil and...capability or availability. The business model, as seen by Demil and Lecocq (2010), delivers dynamic consistency by ensuring that profitability and...business of projects. Cambridge, UK: Cambridge University Press. Demil , B., & Lecocq, X. (2010). Business model evolution: In search of dynamic

  17. Hydropower Baseline Cost Modeling, Version 2

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, Patrick W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Recent resource assessments conducted by the United States Department of Energy have identified significant opportunities for expanding hydropower generation through the addition of power to non-powered dams and on undeveloped stream-reaches. Additional interest exists in the powering of existing water resource infrastructure such as conduits and canals, upgrading and expanding existing hydropower facilities, and the construction new pumped storage hydropower. Understanding the potential future role of these hydropower resources in the nation’s energy system requires an assessment of the environmental and techno-economic issues associated with expanding hydropower generation. To facilitate these assessments, this report seeks to fill the current gaps in publically available hydropower cost estimating tools that can support the national-scale evaluation of hydropower resources.

  18. Cost-effectiveness modelling of telehealth for patients with raised cardiovascular disease risk: evidence from a cohort simulation conducted alongside the Healthlines randomised controlled trial

    Science.gov (United States)

    Dixon, Padraig; Ara, Roberta; Edwards, Louisa; Foster, Alexis

    2016-01-01

    Objectives To investigate the long-term cost-effectiveness (measured as the ratio of incremental NHS cost to incremental quality-adjusted life years) of a telehealth intervention for patients with raised cardiovascular disease (CVD) risk. Design A cohort simulation model developed as part of the economic evaluation conducted alongside the Healthlines randomised controlled trial. Setting Patients recruited through primary care, and intervention delivered via telehealth service. Participants Participants with a 10-year CVD risk ≥20%, as measured by the QRISK2 algorithm, and with at least 1 modifiable risk factor, individually randomised from 42 general practices in England. Intervention A telehealth service delivered over a 12-month period. The intervention involved a series of responsive, theory-led encounters between patients and trained health information advisors who provided access to information resources and supported medication adherence and coordination of care. Primary and secondary outcome measures Cost-effectiveness measured by net monetary benefit over the simulated lifetime of trial participants from a UK National Health Service perspective. Results The probability that the intervention was cost-effective depended on the duration of the effect of the intervention. The intervention was cost-effective with high probability if effects persisted over the lifetime of intervention recipients. The probability of cost-effectiveness was lower for shorter durations of effect. Conclusions The intervention was likely to be cost-effective under a lifetime perspective. Trial registration number ISRCTN27508731; Results. PMID:27670521

  19. How much does it cost? The LIFE Project - Costing Models for Digital Curation and Preservation

    Directory of Open Access Journals (Sweden)

    Richard Davies

    2007-11-01

    Full Text Available Digital preservation is concerned with the long-term safekeeping of electronic resources. How can we be confident of their permanence, if we do not know the cost of preservation? The LIFE (Lifecycle Information for E-Literature Project has made a major step forward in understanding the long-term costs in this complex area. The LIFE Project has developed a methodology to model the digital lifecycle and to calculate the costs of preserving digital information for the next 5, 10 or 100 years. National and higher education (HE libraries can now apply this process and plan effectively for the preservation of their digital collections. Based on previous work undertaken on the lifecycles of paper-based materials, the LIFE Project created a lifecycle model and applied it to real-life digital collections across a diverse subject range. Three case studies examined the everyday operations, processes and costs involved in their respective activities. The results were then used to calculate the direct costs for each element of the digital lifecycle. The Project has made major advances in costing preservation activities, as well as making detailed costs of real digital preservation activities available. The second phase of LIFE (LIFE2, which recently started, aims to refine the lifecycle methodology and to add a greater range and breadth to the project with additional exemplar case studies.

  20. COST ESTIMATION MODELS FOR DRINKING WATER TREATMENT UNIT PROCESSES

    Science.gov (United States)

    Cost models for unit processes typically utilized in a conventional water treatment plant and in package treatment plant technology are compiled in this paper. The cost curves are represented as a function of specified design parameters and are categorized into four major catego...

  1. Program Demand Cost Model for Alaskan Schools. Eighth Edition.

    Science.gov (United States)

    Morgan, Michael; Mearig, Tim; Coffee, Nathan

    The State of Alaska Department of Education has created a handbook for establishing budgets for the following three types of construction projects: new schools or additions; renovations; and combined new work and renovations. The handbook supports a demand cost model computer program that includes detailed renovation cost data, itemized by…

  2. 76 FR 80941 - Request for Connect America Fund Cost Models

    Science.gov (United States)

    2011-12-27

    ... estimating the costs of providing service over a shared network to all households, businesses and community... that service territory. The Commission also intends to use the forward- looking cost model to identify... scope associated with providing services over a shared network, thereby reducing the per-location...

  3. New Coefficients of the Minority Carrier Lifetime and Bandgap Narrowing Models in the Transparent Emitter of Thin Film Silicon Solar Cells

    OpenAIRE

    2001-01-01

    In this study we have determined new coefficients for the physical model describing the band-gap narrowing and the minority carriers lifetime. This was accomplished according to the doping level of the thin emitter. This model allows us to take into account both the effects of the heavy doping and the majority carrier degeneration for the very high level of doping. The results we obtain by the corrected model are in good agreement with those reported in the literature and in di...

  4. On Transaction-Cost Models in Continuous-Time Markets

    Directory of Open Access Journals (Sweden)

    Thomas Poufinas

    2015-04-01

    Full Text Available Transaction-cost models in continuous-time markets are considered. Given that investors decide to buy or sell at certain time instants, we study the existence of trading strategies that reach a certain final wealth level in continuous-time markets, under the assumption that transaction costs, built in certain recommended ways, have to be paid. Markets prove to behave in manners that resemble those of complete ones for a wide variety of transaction-cost types. The results are important, but not exclusively, for the pricing of options with transaction costs.

  5. Active-Reserve Force Cost Model

    Science.gov (United States)

    2015-01-01

    of either the Department of Defense or the sponsoring organization. Acknowledgments Thank you to Daniel L. Cuda and Michael C. Frieders for performing...policy, 4 Ronald E. Porten, Daniel L. Cuda , and Arthur C. Yengling, “DoD Force & Infrastructure Categories: A FYDP-Based Conceptual Model of...Daniel L. Cuda , and Arthur C. Yengling. “DoD Force & Infrastructure Categories: A FYDP-Based Conceptual Model of Department of Defense Programs and

  6. Computing lifetimes for battery-powered devices

    OpenAIRE

    Jongerden, Marijn; Haverkort, Boudewijn

    2010-01-01

    The battery lifetime of mobile devices depends on the usage pattern of the battery, next to the discharge rate and the battery capacity. Therefore, it is important to include the usage pattern in battery lifetime computations. We do this by combining a stochastic workload, modeled as a continuous-time Markov model, with a well-known battery model. For this combined model, we provide new algorithms to efficiently compute the expected lifetime and the distribution and expected value of the deli...

  7. Cost and cost-effectiveness of tuberculosis treatment shortening: a model-based analysis.

    Science.gov (United States)

    Gomez, G B; Dowdy, D W; Bastos, M L; Zwerling, A; Sweeney, S; Foster, N; Trajman, A; Islam, M A; Kapiga, S; Sinanovic, E; Knight, G M; White, R G; Wells, W A; Cobelens, F G; Vassall, A

    2016-12-01

    Despite improvements in treatment success rates for tuberculosis (TB), current six-month regimen duration remains a challenge for many National TB Programmes, health systems, and patients. There is increasing investment in the development of shortened regimens with a number of candidates in phase 3 trials. We developed an individual-based decision analytic model to assess the cost-effectiveness of a hypothetical four-month regimen for first-line treatment of TB, assuming non-inferiority to current regimens of six-month duration. The model was populated using extensive, empirically-collected data to estimate the economic impact on both health systems and patients of regimen shortening for first-line TB treatment in South Africa, Brazil, Bangladesh, and Tanzania. We explicitly considered 'real world' constraints such as sub-optimal guideline adherence. From a societal perspective, a shortened regimen, priced at USD1 per day, could be a cost-saving option in South Africa, Brazil, and Tanzania, but would not be cost-effective in Bangladesh when compared to one gross domestic product (GDP) per capita. Incorporating 'real world' constraints reduces cost-effectiveness. Patient-incurred costs could be reduced in all settings. From a health service perspective, increased drug costs need to be balanced against decreased delivery costs. The new regimen would remain a cost-effective option, when compared to each countries' GDP per capita, even if new drugs cost up to USD7.5 and USD53.8 per day in South Africa and Brazil; this threshold was above USD1 in Tanzania and under USD1 in Bangladesh. Reducing the duration of first-line TB treatment has the potential for substantial economic gains from a patient perspective. The potential economic gains for health services may also be important, but will be context-specific and dependent on the appropriate pricing of any new regimen.

  8. Estimation of traffic accident costs: a prompted model.

    Science.gov (United States)

    Hejazi, Rokhshad; Shamsudin, Mad Nasir; Radam, Alias; Rahim, Khalid Abdul; Ibrahim, Zelina Zaitun; Yazdani, Saeed

    2013-01-01

    Traffic accidents are the reason for 25% of unnatural deaths in Iran. The main objective of this study is to find a simple model for the estimation of economic costs especially in Islamic countries (like Iran) in a straightforward manner. The model can show the magnitude of traffic accident costs with monetary equivalent. Data were collected from different sources that included traffic police records, insurance companies and hospitals. The conceptual framework, in our study, was based on the method of Ayati. He used this method for the estimation of economic costs in Iran. We promoted his method via minimum variables. Our final model has only three available variables which can be taken from insurance companies and police records. The running model showed that the traffic accident costs were US$2.2 million in 2007 for our case study route.

  9. Process Setting Models for the Minimization of Costs Defectives ...

    African Journals Online (AJOL)

    Process Setting Models for the Minimization of Costs Defectives. ... Journal Home > Vol 15, No 1 (1991) >. Log in or Register to get access to full text downloads. ... Abstract. The economy of production controls all manufacturing activities. In the ...

  10. An optimal promotion cost control model for a markovian manpower ...

    African Journals Online (AJOL)

    An optimal promotion cost control model for a markovian manpower system. ... Log in or Register to get access to full text downloads. ... A theory concerning the existence of an optimal promotion control strategy for controlling a Markovian ...

  11. Overview of cost-consequence modeling in outcomes research.

    Science.gov (United States)

    Stergachis, A

    1995-01-01

    Outcomes research has developed in response to the need for information on costs, risks, and benefits of clinical treatments, including data regarding the effectiveness of prescription drugs. It attempts to consider more than the biologic effects of pharmaceuticals, that is, to encompass wider measures of the results of their use, issues that are not routinely addressed during clinical trials. Cost-effectiveness analysis compares the outcome of different treatment options in terms of monetary cost per unit of effectiveness. Examples of measures of effectiveness are years of life saved, number of days of hospitalization avoided, and number of treatment successes. Cost-consequence models, also referred to as cost-outcome models, deal with costs and a variety of outcomes ranging from clinical to humanistic. Direct medical costs are those for prevention, detection, treatment, and rehabilitation; they are amounts spent to treat an illness, including hospitalization, professional services, pharmaceuticals, and medical supplies. Indirect medical costs are associated with changes in productivity, such as earnings lost because of illness. Humanistic outcomes deal primarily with functional status, quality of life, and satisfaction, and may include pain, anxiety, self-esteem, ability to carry out normal activities, and overall impressions. Since it is not possible to study all effects of treatments with clinical trials, modeling techniques are useful in making therapeutic decisions.

  12. A cost minimisation analysis in teledermatology: model-based approach

    Directory of Open Access Journals (Sweden)

    Eminović Nina

    2010-08-01

    Full Text Available Abstract Background Although store-and-forward teledermatology is increasingly becoming popular, evidence on its effects on efficiency and costs is lacking. The aim of this study, performed in addition to a clustered randomised trial, was to investigate to what extent and under which conditions store-and-forward teledermatology can reduce costs from a societal perspective. Methods A cost minimisation study design (a model based approach was applied to compare teledermatology and conventional process costs per dermatology patient care episode. Regarding the societal perspective, total mean costs of investment, general practitioner, dermatologists, out-of-pocket expenses and employer costs were calculated. Uncertainty analysis was performed using Monte Carlo simulation with 31 distributions in the used cost model. Scenario analysis was performed using one-way and two-way sensitivity analyses with the following variables: the patient travel distance to physician and dermatologist, the duration of teleconsultation activities, and the proportion of preventable consultations. Results Total mean costs of teledermatology process were €387 (95%CI, 281 to 502.5, while the total mean costs of conventional process costs were €354.0 (95%CI, 228.0 to 484.0. The total mean difference between the processes was €32.5 (95%CI, -29.0 to 74.7. Savings by teledermatology can be achieved if the distance to a dermatologist is larger (> = 75 km or when more consultations (> = 37% can be prevented due to teledermatology. Conclusions Teledermatology, when applied to all dermatology referrals, has a probability of 0.11 of being cost saving to society. In order to achieve cost savings by teledermatology, teledermatology should be applied in only those cases with a reasonable probability that a live consultation can be prevented. Trail Registration This study is performed partially based on PERFECT D Trial (Current Controlled Trials No.ISRCTN57478950.

  13. Solid waste integrated cost analysis model: 1991 project year report

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The purpose of the City of Houston's 1991 Solid Waste Integrated Cost Analysis Model (SWICAM) project was to continue the development of a computerized cost analysis model. This model is to provide solid waste managers with tool to evaluate the dollar cost of real or hypothetical solid waste management choices. Those choices have become complicated by the implementation of Subtitle D of the Resources Conservation and Recovery Act (RCRA) and the EPA's Integrated Approach to managing municipal solid waste;. that is, minimize generation, maximize recycling, reduce volume (incinerate), and then bury (landfill) only the remainder. Implementation of an integrated solid waste management system involving all or some of the options of recycling, waste to energy, composting, and landfilling is extremely complicated. Factors such as hauling distances, markets, and prices for recyclable, costs and benefits of transfer stations, and material recovery facilities must all be considered. A jurisdiction must determine the cost impacts of implementing a number of various possibilities for managing, handling, processing, and disposing of waste. SWICAM employs a single Lotus 123 spreadsheet to enable a jurisdiction to predict or assess the costs of its waste management system. It allows the user to select his own process flow for waste material and to manipulate the model to include as few or as many options as he or she chooses. The model will calculate the estimated cost for those choices selected. The user can then change the model to include or exclude waste stream components, until the mix of choices suits the user. Graphs can be produced as a visual communication aid in presenting the results of the cost analysis. SWICAM also allows future cost projections to be made.

  14. Generomak: Fusion physics, engineering and costing model

    Energy Technology Data Exchange (ETDEWEB)

    Delene, J.G.; Krakowski, R.A.; Sheffield, J.; Dory, R.A.

    1988-06-01

    A generic fusion physics, engineering and economics model (Generomak) was developed as a means of performing consistent analysis of the economic viability of alternative magnetic fusion reactors. The original Generomak model developed at Oak Ridge by Sheffield was expanded for the analyses of the Senior Committee on Environmental Safety and Economics of Magnetic Fusion Energy (ESECOM). This report describes the Generomak code as used by ESECOM. The input data used for each of the ten ESECOM fusion plants and the Generomak code output for each case is given. 14 refs., 3 figs., 17 tabs.

  15. Costs Models in Design and Manufacturing of Sand Casting Products

    CERN Document Server

    Perry, Nicolas; Bernard, Alain

    2010-01-01

    In the early phases of the product life cycle, the costs controls became a major decision tool in the competitiveness of the companies due to the world competition. After defining the problems related to this control difficulties, we will present an approach using a concept of cost entity related to the design and realization activities of the product. We will try to apply this approach to the fields of the sand casting foundry. This work will highlight the enterprise modelling difficulties (limits of a global cost modelling) and some specifics limitations of the tool used for this development. Finally we will discuss on the limits of a generic approach.

  16. Dynamic modeling and simulation of power transformer maintenance costs

    Directory of Open Access Journals (Sweden)

    Ristić Olga

    2016-01-01

    Full Text Available The paper presents the dynamic model of maintenance costs of the power transformer functional components. Reliability is modeled combining the exponential and Weibull's distribution. The simulation was performed with the aim of corrective maintenance and installation of the continuous monitoring system of the most critical components. Simulation Dynamic System (SDS method and VENSIM PLE software was used to simulate the cost. In this way, significant savings in maintenance costs will be achieved with a small initial investment. [Projekat Ministarstva nauke Republike Srbije, br. III 41025 i br. OI 171007

  17. A Monetary Equilibrium Model with Transactions Costs

    OpenAIRE

    Julio J. Rotemberg

    1982-01-01

    This paper presents the competitive equilibrium of an economy in which people hold money for transactions purposes. It studies both the steady states which result from different rates of monetary expansion and the effects of such non-steady state events as an open market operation. Even though the model features no uncertainty and perfect foresight, open market operations affect aggregate output. In particular, a simultaneous increase in money and governmental holdings of capital temporarily ...

  18. A Monetary Equilibrium Model with Transactions Costs

    OpenAIRE

    Julio J. Rotemberg

    1982-01-01

    This paper presents the competitive equilibrium of an economy in which people hold money for transactions purposes. It studies both the steady states which result from different rates of monetary expansion and the effects of such non-steady state events as an open market operation. Even though the model features no uncertainty and perfect foresight, open market operations affect aggregate output. In particular, a simultaneous increase in money and governmental holdings of capital temporarily ...

  19. Modelling the Cost and Quality of Preservation Imaging and Archiving

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad

    2009-01-01

    in the OAIS Reference Model. The cost model divides the OAIS functions in a hierarchy of cost critical activities and measurable components, which are implemented as formulas in a spreadsheet. So far the model has only been completed for activities relating to preservation planning and digital migrations......, fire and other risks. In this PhD thesis it is examined how one may evaluate the long‐term costs and benefits to cultural heritage institutions of different preservation strategies for digital copies. The investigated alternatives are preserving the copies in a digital repository, and printing...... the files out on microfilm and preserving them in a non‐digital repository. In order to obtain empirical data and to understand the decisive cost factors in preservation copying, a case study was set up in which degrading sheet‐film negatives were digitised. Requirements for image quality and metadata were...

  20. A Phenomenological Cost Model for High Energy Particle Accelerators

    CERN Document Server

    Shiltsev, Vladimir

    2014-01-01

    Accelerator-based high-energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the colliders has progressed immensely, while the beam energy, luminosity, facility size, and cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. In this paper we derive a simple scaling model for the cost of large accelerators and colliding beam facilities based on costs of 17 big facilities which have been either built or carefully estimated. Although this approach cannot replace an actual cost estimate based on an engineering design, this parameterization is to indicate a somewhat realistic cost range for consideration of what future frontier accelerator facilities might be fiscally realizable.

  1. A MODEL OF FUZZY CALCULATION OF THE CONSTUCTION COST

    Institute of Scientific and Technical Information of China (English)

    邵良杉; 叶景楼; 李东

    1998-01-01

    An overview of the delelopment of approaches to construction cost and price forcasting since the 1950's is given. First, second and third generation models can be identified, but they all have shortcomings. This paper puts forward a new model, fuzzy calculation model, based on lots of data of the finished projects. Through actual application, it is proved that the model is accurate and quick in calcalation of construction.

  2. A Review of Selected USAF Life Cycle Costing Models

    Science.gov (United States)

    1991-09-01

    Within the Air Force, Headquarters, USAF, Deputy Chief of Staff for Logistics and Engineering, Directorate of Maintenance and Supply (HQ USAF/ LEYE ) is the...to allow the incorporation of a more "user friendly" interface. It also allowed color to be added to the model as well as menu windows. 2. RTD&E...between itself and more traditional logistic cost models and encouraged further use of the model. As mentioned previously, the model provided color

  3. Dynamic modeling of cost-effectiveness of rotavirus vaccination, Kazakhstan.

    Science.gov (United States)

    Freiesleben de Blasio, Birgitte; Flem, Elmira; Latipov, Renat; Kuatbaeva, Ajnagul; Kristiansen, Ivar Sønbø

    2014-01-01

    The government of Kazakhstan, a middle-income country in Central Asia, is considering the introduction of rotavirus vaccination into its national immunization program. We performed a cost-effectiveness analysis of rotavirus vaccination spanning 20 years by using a synthesis of dynamic transmission models accounting for herd protection. We found that a vaccination program with 90% coverage would prevent ≈880 rotavirus deaths and save an average of 54,784 life-years for children vaccine cost at vaccination program costs would be entirely offset. To further evaluate efficacy of a vaccine program, benefits of indirect protection conferred by vaccination warrant further study.

  4. New Approaches in Reusable Booster System Life Cycle Cost Modeling

    Science.gov (United States)

    Zapata, Edgar

    2013-01-01

    This paper presents the results of a 2012 life cycle cost (LCC) study of hybrid Reusable Booster Systems (RBS) conducted by NASA Kennedy Space Center (KSC) and the Air Force Research Laboratory (AFRL). The work included the creation of a new cost estimating model and an LCC analysis, building on past work where applicable, but emphasizing the integration of new approaches in life cycle cost estimation. Specifically, the inclusion of industry processes/practices and indirect costs were a new and significant part of the analysis. The focus of LCC estimation has traditionally been from the perspective of technology, design characteristics, and related factors such as reliability. Technology has informed the cost related support to decision makers interested in risk and budget insight. This traditional emphasis on technology occurs even though it is well established that complex aerospace systems costs are mostly about indirect costs, with likely only partial influence in these indirect costs being due to the more visible technology products. Organizational considerations, processes/practices, and indirect costs are traditionally derived ("wrapped") only by relationship to tangible product characteristics. This traditional approach works well as long as it is understood that no significant changes, and by relation no significant improvements, are being pursued in the area of either the government acquisition or industry?s indirect costs. In this sense then, most launch systems cost models ignore most costs. The alternative was implemented in this LCC study, whereby the approach considered technology and process/practices in balance, with as much detail for one as the other. This RBS LCC study has avoided point-designs, for now, instead emphasizing exploring the trade-space of potential technology advances joined with potential process/practice advances. Given the range of decisions, and all their combinations, it was necessary to create a model of the original model

  5. New Approaches in Reuseable Booster System Life Cycle Cost Modeling

    Science.gov (United States)

    Zapata, Edgar

    2013-01-01

    This paper presents the results of a 2012 life cycle cost (LCC) study of hybrid Reusable Booster Systems (RBS) conducted by NASA Kennedy Space Center (KSC) and the Air Force Research Laboratory (AFRL). The work included the creation of a new cost estimating model and an LCC analysis, building on past work where applicable, but emphasizing the integration of new approaches in life cycle cost estimation. Specifically, the inclusion of industry processes/practices and indirect costs were a new and significant part of the analysis. The focus of LCC estimation has traditionally been from the perspective of technology, design characteristics, and related factors such as reliability. Technology has informed the cost related support to decision makers interested in risk and budget insight. This traditional emphasis on technology occurs even though it is well established that complex aerospace systems costs are mostly about indirect costs, with likely only partial influence in these indirect costs being due to the more visible technology products. Organizational considerations, processes/practices, and indirect costs are traditionally derived ("wrapped") only by relationship to tangible product characteristics. This traditional approach works well as long as it is understood that no significant changes, and by relation no significant improvements, are being pursued in the area of either the government acquisition or industry?s indirect costs. In this sense then, most launch systems cost models ignore most costs. The alternative was implemented in this LCC study, whereby the approach considered technology and process/practices in balance, with as much detail for one as the other. This RBS LCC study has avoided point-designs, for now, instead emphasizing exploring the trade-space of potential technology advances joined with potential process/practice advances. Given the range of decisions, and all their combinations, it was necessary to create a model of the original model

  6. Preindustrial to present day changes in tropospheric hydroxyl radical and methane lifetime from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP

    Directory of Open Access Journals (Sweden)

    V. Naik

    2012-11-01

    Full Text Available We have analysed results from 17 global models, participating in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP, to explore trends in hydroxyl radical concentration (OH and methane (CH4 lifetime since preindustrial times (1850 and gain a better understanding of their key drivers. For the present day (2000, the models tend to simulate higher OH abundances in the Northern Hemisphere versus Southern Hemisphere. Evaluation of simulated carbon monoxide concentrations, the primary sink for OH, against observations suggests low biases in the Northern Hemisphere that may contribute to the high north-south OH asymmetry in the models. A comparison of modelled and observed methyl chloroform lifetime suggests that the present day global multi-model mean OH concentration is slightly overestimated. Despite large regional changes, the modelled global mean OH concentration is roughly constant over the past 150 yr, due to concurrent increases in OH sources (humidity, tropospheric ozone, and NOx emissions, together with decreases in stratospheric ozone and increase in tropospheric temperature, compensated by increases in OH sinks (methane abundance, carbon monoxide and non-methane volatile organic carbon (NMVOC emissions. The large intermodel diversity in the sign and magnitude of OH and methane lifetime changes over this period reflects differences in the relative importance of chemical and physical drivers of OH within each model. For the 1980 to 2000 period, we find that climate warming and a slight increase in mean OH leads to a 4.3 ± 1.9% decrease in the methane lifetime. Analysing sensitivity simulations performed by 10 models, we find that preindustrial to present day climate change decreased the methane lifetime by about 4 months, representing a negative feedback on the climate system. Further, using a subset of the models, we find that global mean OH increased by 46.4 ± 12.2% in response to

  7. A Layered Decision Model for Cost-Effective System Security

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Huaqiang; Alves-Foss, James; Soule, Terry; Pforsich, Hugh; Zhang, Du; Frincke, Deborah A.

    2008-10-01

    System security involves decisions in at least three areas: identification of well-defined security policies, selection of cost-effective defence strategies, and implementation of real-time defence tactics. Although choices made in each of these areas affect the others, existing decision models typically handle these three decision areas in isolation. There is no comprehensive tool that can integrate them to provide a single efficient model for safeguarding a network. In addition, there is no clear way to determine which particular combinations of defence decisions result in cost-effective solutions. To address these problems, this paper introduces a Layered Decision Model (LDM) for use in deciding how to address defence decisions based on their cost-effectiveness. To validate the LDM and illustrate how it is used, we used simulation to test model rationality and applied the LDM to the design of system security for an e-commercial business case.

  8. Modeling the lowest-cost splitting of a herd of cows by optimizing a cost function

    OpenAIRE

    Gajamannage, Kelum; Bollt, Erik M; Porter, Mason A.; Dawkins, Marian S.

    2016-01-01

    Animals live in groups to defend against predation and to obtain food. However, for some animals --- especially ones that spend long periods of time feeding --- there are costs if a group chooses to move on before their nutritional needs are satisfied. If the conflict between feeding and keeping up with a group becomes too large, it may be advantageous to some animals to split into subgroups of animals with similar nutritional needs. We model the costs and benefits of splitting by a herd of c...

  9. Estimating the cost-effectiveness of lifestyle intervention programmes to prevent diabetes based on an example from Germany: Markov modelling

    Directory of Open Access Journals (Sweden)

    Neumann Anne

    2011-11-01

    Full Text Available Abstract Background Type 2 diabetes mellitus (T2D poses a large worldwide burden for health care systems. One possible tool to decrease this burden is primary prevention. As it is unethical to wait until perfect data are available to conclude whether T2D primary prevention intervention programmes are cost-effective, we need a model that simulates the effect of prevention initiatives. Thus, the aim of this study is to investigate the long-term cost-effectiveness of lifestyle intervention programmes for the prevention of T2D using a Markov model. As decision makers often face difficulties in applying health economic results, we visualise our results with health economic tools. Methods We use four-state Markov modelling with a probabilistic cohort analysis to calculate the cost per quality-adjusted life year (QALY gained. A one-year cycle length and a lifetime time horizon are applied. Best available evidence supplies the model with data on transition probabilities between glycaemic states, mortality risks, utility weights, and disease costs. The costs are calculated from a societal perspective. A 3% discount rate is used for costs and QALYs. Cost-effectiveness acceptability curves are presented to assist decision makers. Results The model indicates that diabetes prevention interventions have the potential to be cost-effective, but the outcome reveals a high level of uncertainty. Incremental cost-effectiveness ratios (ICERs were negative for the intervention, ie, the intervention leads to a cost reduction for men and women aged 30 or 50 years at initiation of the intervention. For men and women aged 70 at initiation of the intervention, the ICER was EUR27,546/QALY gained and EUR19,433/QALY gained, respectively. In all cases, the QALYs gained were low. Cost-effectiveness acceptability curves show that the higher the willingness-to-pay threshold value, the higher the probability that the intervention is cost-effective. Nonetheless, all curves are

  10. Batteries 2020 – Lithium - ion battery first and second life ageing, validated battery models, lifetime modelling and ageing assessment of thermal parameters

    DEFF Research Database (Denmark)

    Timmermans, Jean-Marc; Nikolian, Alexandros; De Hoog, Joris

    2016-01-01

    The European Project “Batteries 2020” unites nine partners jointly working on research and the development of competitive European automotive batteries. The project aims at increasing both the energy density and lifetime of large format pouch lithium-ion batteries towards the goals targeted...... for automotive batteries (250 Wh/kg at cell level, over 4000 cycles at 80% depth of discharge). Three parallel strategies are followed in order to achieve those targets: (i) Highly focused materials development; two improved generations of NMC cathode materials allows to improve the performance, stability...... and cyclability of state of the art battery cells. (ii) Better understanding of the ageing phenomena; a robust and realistic testing methodology has been developed and was carried out. Combined accelerated, real driving cycle tests, real field data, post - mortem analysis, modelling and validation with real...

  11. Production Cost Optimization Model Based on CODP in Mass Customization

    Directory of Open Access Journals (Sweden)

    Yanhong Qin

    2013-01-01

    Full Text Available The key for enterprises to implement the postponement strategy is the right decision on the location of Customer Order Decoupling Point (CODP so as to achieve the scope economics of mass customization and scale economics of mass production fully. To deal with production cost optimization problem of postponement system based on various situation of CODP, a basic model of production cost and its M/M/1 extended model are proposed and compared so as to optimize the overall production cost of the postponement system. The production modes can be classified as MTS (make to stock, ATO (assemble to order, MTO (make to order and ETO (engineering to order according to the inventory location, and the postponed production system considered here includes manufacturing cost, semi-finished inventory cost and customer waiting cost caused by delaying delivery. By Matlab simulation, we can compute the optimal location of CODP in each production mode, which can provide some management insight for the manufacturer to decide the right production mode and utilize the resources efficiently.

  12. Prices and Market Shares in a Menu Cost Model

    OpenAIRE

    Burstein, Ariel Tomas; Hellwig, Christian

    2007-01-01

    Pricing complementarities play a key role in determining the propagation of monetary disturbances in sticky price models. We propose a procedure to infer the degree of firm-level pricing complementarities in the context of a menu cost model of price adjustment using data on prices and market shares at the level of individual varieties. We then apply this procedure by calibrating our model (in which pricing complementarities are based on decreasing returns to scale at the variety level) using ...

  13. Model for Determining Fixed Costs for the Winter Service Operation

    Directory of Open Access Journals (Sweden)

    Matija Glad

    2006-07-01

    Full Text Available From the season 2005!06 a new dynamic model for the operationof the Winter Service in the Republic of Croatia will beused. The old model was based on three levels of readiness, andthe roads were categorised primarily according to their administrativedistribution. The new dynamic model has three levelsof readiness, while the first level is further divided into two servicelevels. The road is classified to a certain readiness and servicelevel according to the traffic, climate and economic conditions.The new model splits the cost structure into fixed and variablecosts. The investor wants to keep the fixed costs at a minimal/eve~ which will guarantee proper readiness for quick intervention.The investor wants to ensure a technological infrastructurefor quality cleaning of roads is created. The capitalcompanies want larger fixed costs to ensure certain profit, anddefined fixed costs enable them to asses the profitability of theWinter Service operation. Such structure fonils the followingrelationship: in mild winters the capital companies "profit" andthe investor "loses", and vice versa for cold winters. Mathematically,such relationship should be treated as a finite strategictwo-player game.This paper will show the model needed to forecast fixedcosts in the new dynamic model for operation of Winter Ser·vice, through consideration of connection of linear programmingand the matrix game theory, to study the problem in parallel,from the standpoint of both players.

  14. Life Cycle Cost Model for Very High Speed Integrated Circuits.

    Science.gov (United States)

    1984-09-01

    circuitry of the finished product level. ASD/ACCC has access to PRICE M on UNINET (30). 4. PRICE H (Programmed Review of Information for Costing and...AWAL/AAAS- 2) has successfully used PRICE H to analyze hardware acquisition costs. ASD/ACCC has access to PRICE H on UNINET ,-I" (13:1).• 5. PRICE L...ASD/ACCC has access to this model on UNINET (17:21). VHSIC Program Description As discussed earlier, LCC modeling includes all phases of a system’s

  15. BUSINESS PROCESS MODELLING FOR PROJECTS COSTS MANAGEMENT IN AN ORGANIZATION

    Directory of Open Access Journals (Sweden)

    PĂTRAŞCU AURELIA

    2014-05-01

    Full Text Available Using Information Technologies in organizations represents an evident progress for company, money economy, time economy and generates value for the organization. In this paper the author proposes to model the business processes for an organization that manages projects costs, because modelling is an important part of any software development process. Using software for projects costs management is essential because it allows the management of all operations according to the established parameters, the management of the projects groups, as well as the management of the projects and subprojects, at different complexity levels.

  16. O&M Cost Modeling for the Department of Defense

    Science.gov (United States)

    2015-01-01

    IDA Document D-5279 January 2015 O &M Cost Modeling for the Department of Defense Brian G. Gladstone, Project Leader Brandon R. Gould Karen L...Johnson Log: H 14-000973 INSTITUTE FOR DEFENSE ANALYSES 4850 Mark Center Drive Alexandria, Virginia 22311-1882 I N S T I T U T E F O R D E F E N S E A N...Analyses (IDA) under contract DASW01-04-C-0003, Task AO-7-3688, “ O &M Cost Modeling for the Department of Defense,” for the Director, Acquisition

  17. Standard Cost Model: Three Different Paths and their Common Problems

    Directory of Open Access Journals (Sweden)

    Jacopo Torriti

    2011-12-01

    Full Text Available Red tape is not desirable as it impedes business growth. Relief from the administrative burdens that businesses face due to legislation can benefit the whole economy, especially at times of recession. However, recent governmental initiatives aimed at reducing administrative burdens have encountered some success, but also failures. This article compares three national initiatives – in the Netherlands, UK and Italy - aimed at cutting red tape by using the Standard Cost Model. Findings highlight the factors affecting the outcomes of measurement and reduction plans and ways to improve the Standard Cost Model methodology.

  18. New Coefficients of the Minority Carrier Lifetime and Bandgap Narrowing Models in the Transparent Emitter of Thin Film Silicon Solar Cells

    OpenAIRE

    2003-01-01

    In this study we have determined new coefficients for the physical model describing the band-gap narrowing and the minority carriers lifetime. This was accomplished according to the doping level of the thin emitter. This model allows us to take into account both the effects of the heavy doping and the majority carrier degeneration for the very high level of doping. The results we obtain by the corrected model are in good agreement with those reported in the literature and in different expe...

  19. ICU early physical rehabilitation programs: financial modeling of cost savings.

    Science.gov (United States)

    Lord, Robert K; Mayhew, Christopher R; Korupolu, Radha; Mantheiy, Earl C; Friedman, Michael A; Palmer, Jeffrey B; Needham, Dale M

    2013-03-01

    To evaluate the potential annual net cost savings of implementing an ICU early rehabilitation program. Using data from existing publications and actual experience with an early rehabilitation program in the Johns Hopkins Hospital Medical ICU, we developed a model of net financial savings/costs and presented results for ICUs with 200, 600, 900, and 2,000 annual admissions, accounting for both conservative- and best-case scenarios. Our example scenario provided a projected financial analysis of the Johns Hopkins Medical ICU early rehabilitation program, with 900 admissions per year, using actual reductions in length of stay achieved by this program. U.S.-based adult ICUs. Financial modeling of the introduction of an ICU early rehabilitation program. Net cost savings generated in our example scenario, with 900 annual admissions and actual length of stay reductions of 22% and 19% for the ICU and floor, respectively, were $817,836. Sensitivity analyses, which used conservative- and best-case scenarios for length of stay reductions and varied the per-day ICU and floor costs, across ICUs with 200-2,000 annual admissions, yielded financial projections ranging from -$87,611 (net cost) to $3,763,149 (net savings). Of the 24 scenarios included in these sensitivity analyses, 20 (83%) demonstrated net savings, with a relatively small net cost occurring in the remaining four scenarios, mostly when simultaneously combining the most conservative assumptions. A financial model, based on actual experience and published data, projects that investment in an ICU early rehabilitation program can generate net financial savings for U.S. hospitals. Even under the most conservative assumptions, the projected net cost of implementing such a program is modest relative to the substantial improvements in patient outcomes demonstrated by ICU early rehabilitation programs.

  20. Economic evaluation of newborn hearing screening: modelling costs and outcomes

    Directory of Open Access Journals (Sweden)

    von Voß, Hubertus

    2003-12-01

    Full Text Available Objectives: The prevalence of newborn hearing disorders is 1-3 per 1,000. Crucial for later outcome are correct diagnosis and effective treatment as soon as possible. With BERA and TEOAE low-risk techniques for early detection are available. Universal screening is recommended but not realised in most European health care systems.Aim of the study was to examine the scientific evidence of newborn hearing screening and a comparison of medical outcome and costs of different programmes, differentiated by type of strategy (risk screening, universal screening, no systematical screening. Methods: In an interdisciplinary health technology assessment project all studies on newborn hearing screening detected in a standardized comprehensive literature search were identified and data on medical outcome, costs, and cost-effectiveness extracted. A Markov model was designed to calculate cost-effectiveness ratios. Results: Economic data were extracted from 20 relevant publications out of 39 publications found. In the model total costs for screening of 100,000 newborns with a time horizon of ten years were calculated: 2.0 Mio.€ for universal screening (U, 1.0 Mio.€ for risk screening (R, and 0.6 Mio.€ for no screening (N. The costs per child detected: 13,395€ (U respectively 6,715€ (R, and 4,125€ (N. At 6 months of life the following percentages of cases are detected: U 72%, R 43%, N 13%. Conclusions: A remarkable small number of economic publications mainly of low methodological quality was found. In our own model we found reasonable cost-effectiveness ratios also for universal screening. Considering the outcome advantages of higher numbers of detected cases a universal newborn hearing screening is recommended.

  1. Enzymatic corn wet milling: engineering process and cost model

    Directory of Open Access Journals (Sweden)

    McAloon Andrew J

    2009-01-01

    Full Text Available Abstract Background Enzymatic corn wet milling (E-milling is a process derived from conventional wet milling for the recovery and purification of starch and co-products using proteases to eliminate the need for sulfites and decrease the steeping time. In 2006, the total starch production in USA by conventional wet milling equaled 23 billion kilograms, including modified starches and starches used for sweeteners and ethanol production 1. Process engineering and cost models for an E-milling process have been developed for a processing plant with a capacity of 2.54 million kg of corn per day (100,000 bu/day. These models are based on the previously published models for a traditional wet milling plant with the same capacity. The E-milling process includes grain cleaning, pretreatment, enzymatic treatment, germ separation and recovery, fiber separation and recovery, gluten separation and recovery and starch separation. Information for the development of the conventional models was obtained from a variety of technical sources including commercial wet milling companies, industry experts and equipment suppliers. Additional information for the present models was obtained from our own experience with the development of the E-milling process and trials in the laboratory and at the pilot plant scale. The models were developed using process and cost simulation software (SuperPro Designer® and include processing information such as composition and flow rates of the various process streams, descriptions of the various unit operations and detailed breakdowns of the operating and capital cost of the facility. Results Based on the information from the model, we can estimate the cost of production per kilogram of starch using the input prices for corn, enzyme and other wet milling co-products. The work presented here describes the E-milling process and compares the process, the operation and costs with the conventional process. Conclusion The E-milling process

  2. Cost-effectiveness of total hip and knee replacements for the Australian population with osteoarthritis: discrete-event simulation model.

    Directory of Open Access Journals (Sweden)

    Hideki Higashi

    Full Text Available BACKGROUND: Osteoarthritis constitutes a major musculoskeletal burden for the aged Australians. Hip and knee replacement surgeries are effective interventions once all conservative therapies to manage the symptoms have been exhausted. This study aims to evaluate the cost-effectiveness of hip and knee replacements in Australia. To our best knowledge, the study is the first attempt to account for the dual nature of hip and knee osteoarthritis in modelling the severities of right and left joints separately. METHODOLOGY/PRINCIPAL FINDINGS: We developed a discrete-event simulation model that follows up the individuals with osteoarthritis over their lifetimes. The model defines separate attributes for right and left joints and accounts for several repeat replacements. The Australian population with osteoarthritis who were 40 years of age or older in 2003 were followed up until extinct. Intervention effects were modelled by means of disability-adjusted life-years (DALYs averted. Both hip and knee replacements are highly cost effective (AUD 5,000 per DALY and AUD 12,000 per DALY respectively under an AUD 50,000/DALY threshold level. The exclusion of cost offsets, and inclusion of future unrelated health care costs in extended years of life, did not change the findings that the interventions are cost-effective (AUD 17,000 per DALY and AUD 26,000 per DALY respectively. However, there was a substantial difference between hip and knee replacements where surgeries administered for hips were more cost-effective than for knees. CONCLUSIONS/SIGNIFICANCE: Both hip and knee replacements are cost-effective interventions to improve the quality of life of people with osteoarthritis. It was also shown that the dual nature of hip and knee OA should be taken into account to provide more accurate estimation on the cost-effectiveness of hip and knee replacements.

  3. An Instructional Cost Estimation Model for the XYZ Community College.

    Science.gov (United States)

    Edmonson, William F.

    An enrollment-driven model for estimating instructional costs is presented in this paper as developed by the Western Interstate Commission for Higher Education (WICHE). After stating the principles of the WICHE planning system (i.e., various categories of data are gathered, segmented, and then cross-tabulated against one another to yield certain…

  4. SCGE modelling in cost-benefit analysis: the Dutch experience

    NARCIS (Netherlands)

    Koopmans, C.; Oosterhaven, J.

    2011-01-01

    Spatial computable general equilibrium (SCGE) models offer opportunities for computing wider economic effects in cost-benefit analysis (CBA) in a theoretically satisfactory way. This is important for the correct estimation of additional economic benefits and international relocation impacts. In the

  5. An Examination of Operational Availability in Life Cycle Cost Models

    Science.gov (United States)

    1983-09-01

    Systems. Kenneth E. Marks, H. Garrison Massey, and Brent D. Bradley. Rand No. R-2287-AF. Santa Monica CA: The Rand Corporation, October 1978. AD...AFB OH, September 1982. AD A123045. Bryan, Noreen S.; Jacqueline J. Rosen; and Nancey T. Marland. "A New Life Cycle Cost Model: Flexible, Interactive

  6. Costly innovators versus cheap imitators: a discrete choice model

    NARCIS (Netherlands)

    Hommes, C.; Zeppini, P.

    2010-01-01

    Two alternative ways to an innovative product or process are R&D investment or imitation of others’ innovation. In this article we propose a discrete choice model with costly innovators and free imitators and study the endogenous dynamics of price and demand in a market with many firms producing a h

  7. Application of Improved Grey Prediction Model to Petroleum Cost Forecasting

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The grey theory is a multidisciplinary and generic theory that deals with systems that lack adequate information and/or have only poor information. In this paper, an improved grey model using step function was proposed.Petroleum cost forecast of the Henan oil field was used as the case study to test the efficiency and accuracy of the proposed method. According to the experimental results, the proposed method obviously could improve the prediction accuracy of the original grey model.

  8. Linear versus quadratic portfolio optimization model with transaction cost

    Science.gov (United States)

    Razak, Norhidayah Bt Ab; Kamil, Karmila Hanim; Elias, Siti Masitah

    2014-06-01

    Optimization model is introduced to become one of the decision making tools in investment. Hence, it is always a big challenge for investors to select the best model that could fulfill their goal in investment with respect to risk and return. In this paper we aims to discuss and compare the portfolio allocation and performance generated by quadratic and linear portfolio optimization models namely of Markowitz and Maximin model respectively. The application of these models has been proven to be significant and popular among others. However transaction cost has been debated as one of the important aspects that should be considered for portfolio reallocation as portfolio return could be significantly reduced when transaction cost is taken into consideration. Therefore, recognizing the importance to consider transaction cost value when calculating portfolio' return, we formulate this paper by using data from Shariah compliant securities listed in Bursa Malaysia. It is expected that, results from this paper will effectively justify the advantage of one model to another and shed some lights in quest to find the best decision making tools in investment for individual investors.

  9. INTEGRATED COST MODEL FOR IMPROVING THE PRODUCTION IN COMPANIES

    Directory of Open Access Journals (Sweden)

    Zuzana Hajduova

    2014-12-01

    Full Text Available Purpose: All processes in the company play important role in ensuring functional integrated management system. We point out the importance of need for a systematic approach to the use of quantitative, but especially statistical methods for modelling the cost of the improvement activities that are part of an integrated management system. Development of integrated management systems worldwide leads towards building of systematic procedures of implementation maintenance and improvement of all systems according to the requirements of all the sides involved.Methodology: Statistical evaluation of the economic indicators of improvement costs and the need for a systematic approach to their management in terms of integrated management systems have become a key role also in the management of processes in the company Cu Drôt, a.s. The aim of this publication is to highlight the importance of proper implementation of statistical methods in the process of improvement costs management in the integrated management system of current market conditions and document the legitimacy of a systematic approach in the area of monitoring and analysing indicators of improvement with the aim of the efficient process management of company. We provide specific example of the implementation of appropriate statistical methods in the production of copper wire in a company Cu Drôt, a.s. This publication also aims to create a model for the estimation of integrated improvement costs, which through the use of statistical methods in the company Cu Drôt, a.s. is used to support decision-making on improving efficiency.Findings: In the present publication, a method for modelling the improvement process, by an integrated manner, is proposed. It is a method in which the basic attributes of the improvement in quality, safety and environment are considered and synergistically combined in the same improvement project. The work examines the use of sophisticated quantitative, especially

  10. Use of satellite data to constrain the model-calculated atmospheric lifetime for N2O - Implications for other trace gases

    Science.gov (United States)

    Ko, Malcolm K. W.; Sze, Nien Dak; Weisenstein, Debra K.

    1991-01-01

    Model calculations of the zonal-mean concentrations of N2O in the upper stratosphere are presented showing that about 80 percent of N2O is removed in the stratosphere between 30 deg N and 30 deg S. A comparison of calculated N2O values with remote data on N2O concentrations obtained from Nimbus 7 SAMS instrument indicated that the two-dimensional model of Ko and Sze (1982) may have underestimated the concentration of N2O in the tropical lower stratosphere. It is concluded that the calculated lifetimes for N2O and chlorofluorocarbon-source gases could be 30 percent shorter than previously reported values.

  11. Atmospheric lifetimes and Ozone Depletion Potentials of trans-1-chloro-3,3,3-trifluoropropylene and trans-1,2-dichloroethylene in a three-dimensional model

    Science.gov (United States)

    Patten, K. O.; Wuebbles, D. J.

    2010-11-01

    The chloroalkenes trans-1-chloro-3,3,3-trifluoropropylene (tCFP) and trans-1,2-dichloroethylene (tDCE) have been proposed as candidate replacements for other compounds in current use that cause concerns regarding potential environmental effects including destruction of stratospheric ozone. Because tCFP and tDCE contain chlorine atoms, the effects of these short-lived compounds on stratospheric ozone must be established. In this study, we derive the atmospheric lifetimes and Ozone Depletion Potentials (ODPs) for tCFP and for tDCE assuming emissions from land surfaces at latitudes 30° N to 60° N using the MOZART 3 three-dimensional model of atmospheric chemistry and physics. 53% of the ozone loss due to tCFP and 98% of the ozone loss due to tDCE take place in the troposphere, rather than in the stratosphere as generally expected from longer-lived chlorocarbons. The atmospheric lifetime of tCFP against chemical reaction is 40.4 days, and its ODP is quite small at 0.00034. The tDCE atmospheric lifetime is 12.7 days, and its ODP is 0.00024, which is the lowest ODP found for any chlorocarbon we have studied. Our study suggests that chlorine from tCFP and tDCE are unlikely to affect ozone at quantities likely to be emitted to the atmosphere.

  12. Atmospheric lifetimes and Ozone Depletion Potentials of trans-1-chloro-3,3,3-trifluoropropylene and trans-1,2-dichloroethylene in a three-dimensional model

    Directory of Open Access Journals (Sweden)

    K. O. Patten

    2010-11-01

    Full Text Available The chloroalkenes trans-1-chloro-3,3,3-trifluoropropylene (tCFP and trans-1,2-dichloroethylene (tDCE have been proposed as candidate replacements for other compounds in current use that cause concerns regarding potential environmental effects including destruction of stratospheric ozone. Because tCFP and tDCE contain chlorine atoms, the effects of these short-lived compounds on stratospheric ozone must be established. In this study, we derive the atmospheric lifetimes and Ozone Depletion Potentials (ODPs for tCFP and for tDCE assuming emissions from land surfaces at latitudes 30° N to 60° N using the MOZART 3 three-dimensional model of atmospheric chemistry and physics. 53% of the ozone loss due to tCFP and 98% of the ozone loss due to tDCE take place in the troposphere, rather than in the stratosphere as generally expected from longer-lived chlorocarbons. The atmospheric lifetime of tCFP against chemical reaction is 40.4 days, and its ODP is quite small at 0.00034. The tDCE atmospheric lifetime is 12.7 days, and its ODP is 0.00024, which is the lowest ODP found for any chlorocarbon we have studied. Our study suggests that chlorine from tCFP and tDCE are unlikely to affect ozone at quantities likely to be emitted to the atmosphere.

  13. EFFICIENCY AND COST MODELLING OF THERMAL POWER PLANTS

    Directory of Open Access Journals (Sweden)

    Péter Bihari

    2010-01-01

    Full Text Available The proper characterization of energy suppliers is one of the most important components in the modelling of the supply/demand relations of the electricity market. Power generation capacity i. e. power plants constitute the supply side of the relation in the electricity market. The supply of power stations develops as the power stations attempt to achieve the greatest profit possible with the given prices and other limitations. The cost of operation and the cost of load increment are thus the most important characteristics of their behaviour on the market. In most electricity market models, however, it is not taken into account that the efficiency of a power station also depends on the level of the load, on the type and age of the power plant, and on environmental considerations. The trade in electricity on the free market cannot rely on models where these essential parameters are omitted. Such an incomplete model could lead to a situation where a particular power station would be run either only at its full capacity or else be entirely deactivated depending on the prices prevailing on the free market. The reality is rather that the marginal cost of power generation might also be described by a function using the efficiency function. The derived marginal cost function gives the supply curve of the power station. The load level dependent efficiency function can be used not only for market modelling, but also for determining the pollutant and CO2 emissions of the power station, as well as shedding light on the conditions for successfully entering the market. Based on the measurement data our paper presents mathematical models that might be used for the determination of the load dependent efficiency functions of coal, oil, or gas fuelled power stations (steam turbine, gas turbine, combined cycle and IC engine based combined heat and power stations. These efficiency functions could also contribute to modelling market conditions and determining the

  14. A dynamic model for costing disaster mitigation policies.

    Science.gov (United States)

    Altay, Nezih; Prasad, Sameer; Tata, Jasmine

    2013-07-01

    The optimal level of investment in mitigation strategies is usually difficult to ascertain in the context of disaster planning. This research develops a model to provide such direction by relying on cost of quality literature. This paper begins by introducing a static approach inspired by Joseph M. Juran's cost of quality management model (Juran, 1951) to demonstrate the non-linear trade-offs in disaster management expenditure. Next it presents a dynamic model that includes the impact of dynamic interactions of the changing level of risk, the cost of living, and the learning/investments that may alter over time. It illustrates that there is an optimal point that minimises the total cost of disaster management, and that this optimal point moves as governments learn from experience or as states get richer. It is hoped that the propositions contained herein will help policymakers to plan, evaluate, and justify voluntary disaster mitigation expenditures. © 2013 The Author(s). Journal compilation © Overseas Development Institute, 2013.

  15. Degradation Behavior of Lithium-Ion Batteries Based on Lifetime Models and Field Measured Frequency Regulation Mission Profile

    DEFF Research Database (Denmark)

    Stroe, Daniel Loan; Swierczynski, Maciej Jozef; Stroe, Ana-Irina

    2016-01-01

    is their higher cost—in comparison with other storage technologies or with the traditional frequency regulation methods—combined with performance-degradation uncertainties. In order to surpass this challenge and to allow for optimal sizing and proper operation of the battery, accurate knowledge about the lifetime......Energy storage systems based on Lithium-ion (Li-ion) batteries have been proposed as an environmentally friendly alternative to traditional conventional generating units for providing grid frequency regulation. One major challenge regarding the use of Lithium-ion batteries in such applications...

  16. Product Cost Management Structures: a review and neural network modelling

    Directory of Open Access Journals (Sweden)

    P. Jha

    2003-11-01

    Full Text Available This paper reviews the growth of approaches in product costing and draws synergies with information management and resource planning systems, to investigate potential application of state of the art modelling techniques of neural networks. Increasing demands on costing systems to serve multiple decision-making objectives, have made it essential to use better techniques for analysis of available data. This need is highlighted in the paper. The approach of neural networks, which have several analogous facets to complement and aid the information demands of modern product costing, Enterprise Resource Planning (ERP structures and the dominant-computing environment (for information management in the object oriented paradigm form the domain for investigation. Simulated data is used in neural network applications across activities that consume resources and deliver products, to generate information for monitoring and control decisions. The results in application for feature extraction and variation detection and their implications are presented in the paper.

  17. Developing a Cost Model and Methodology to Estimate Capital Costs for Thermal Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Glatzmaier, G.

    2011-12-01

    This report provides an update on the previous cost model for thermal energy storage (TES) systems. The update allows NREL to estimate the costs of such systems that are compatible with the higher operating temperatures associated with advanced power cycles. The goal of the Department of Energy (DOE) Solar Energy Technology Program is to develop solar technologies that can make a significant contribution to the United States domestic energy supply. The recent DOE SunShot Initiative sets a very aggressive cost goal to reach a Levelized Cost of Energy (LCOE) of 6 cents/kWh by 2020 with no incentives or credits for all solar-to-electricity technologies.1 As this goal is reached, the share of utility power generation that is provided by renewable energy sources is expected to increase dramatically. Because Concentrating Solar Power (CSP) is currently the only renewable technology that is capable of integrating cost-effective energy storage, it is positioned to play a key role in providing renewable, dispatchable power to utilities as the share of power generation from renewable sources increases. Because of this role, future CSP plants will likely have as much as 15 hours of Thermal Energy Storage (TES) included in their design and operation. As such, the cost and performance of the TES system is critical to meeting the SunShot goal for solar technologies. The cost of electricity from a CSP plant depends strongly on its overall efficiency, which is a product of two components - the collection and conversion efficiencies. The collection efficiency determines the portion of incident solar energy that is captured as high-temperature thermal energy. The conversion efficiency determines the portion of thermal energy that is converted to electricity. The operating temperature at which the overall efficiency reaches its maximum depends on many factors, including material properties of the CSP plant components. Increasing the operating temperature of the power generation

  18. Program Demand Cost Model for Alaskan Schools. 6th Edition. Revised.

    Science.gov (United States)

    Alaska State Dept. of Education, Juneau.

    The Program Demand Cost Model for Alaskan Schools (Cost Model) is a tool for use by school districts and their consultants in estimating school construction costs in the planning phase of a project. This document sets out the sixth edition of the demand-cost model, a rewrite of the whole system. The model can be used to establish a complete budget…

  19. Quality and Growth Implications of Incremental Costing Models for Distance Education Units

    Science.gov (United States)

    Crawford, C. B.; Gould, Lawrence V.; King, Dennis; Parker, Carl

    2010-01-01

    The purpose of this article is to explore quality and growth implications emergent from various incremental costing models applied to distance education units. Prior research relative to costing models and three competing costing models useful in the current distance education environment are discussed. Specifically, the simple costing model, unit…

  20. Preindustrial to present-day changes in tropospheric hydroxyl radical and methane lifetime from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP

    Directory of Open Access Journals (Sweden)

    V. Naik

    2013-05-01

    Full Text Available We have analysed time-slice simulations from 17 global models, participating in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP, to explore changes in present-day (2000 hydroxyl radical (OH concentration and methane (CH4 lifetime relative to preindustrial times (1850 and to 1980. A comparison of modeled and observation-derived methane and methyl chloroform lifetimes suggests that the present-day global multi-model mean OH concentration is overestimated by 5 to 10% but is within the range of uncertainties. The models consistently simulate higher OH concentrations in the Northern Hemisphere (NH compared with the Southern Hemisphere (SH for the present-day (2000; inter-hemispheric ratios of 1.13 to 1.42, in contrast to observation-based approaches which generally indicate higher OH in the SH although uncertainties are large. Evaluation of simulated carbon monoxide (CO concentrations, the primary sink for OH, against ground-based and satellite observations suggests low biases in the NH that may contribute to the high north–south OH asymmetry in the models. The models vary widely in their regional distribution of present-day OH concentrations (up to 34%. Despite large regional changes, the multi-model global mean (mass-weighted OH concentration changes little over the past 150 yr, due to concurrent increases in factors that enhance OH (humidity, tropospheric ozone, nitrogen oxide (NOx emissions, and UV radiation due to decreases in stratospheric ozone, compensated by increases in OH sinks (methane abundance, carbon monoxide and non-methane volatile organic carbon (NMVOC emissions. The large inter-model diversity in the sign and magnitude of preindustrial to present-day OH changes (ranging from a decrease of 12.7% to an increase of 14.6% indicate that uncertainty remains in our understanding of the long-term trends in OH and methane lifetime. We show that this diversity is largely explained by the different ratio of the

  1. Preindustrial to Present-Day Changes in Tropospheric Hydroxyl Radical and Methane Lifetime from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)

    Science.gov (United States)

    Naik, V.; Voulgarakis, A.; Fiore, A. M.; Horowitz, L. W.; Lamarque, J.-F.; Lin, M.; Prather, M. J.; Young, P. J.; Bergmann, D.; Cameron-Smith, P. J.; hide

    2013-01-01

    We have analysed time-slice simulations from 17 global models, participating in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), to explore changes in present-day (2000) hydroxyl radical (OH) concentration and methane (CH4) lifetime relative to preindustrial times (1850) and to 1980. A comparison of modeled and observation-derived methane and methyl chloroform lifetimes suggests that the present-day global multi-model mean OH concentration is overestimated by 5 to 10% but is within the range of uncertainties. The models consistently simulate higher OH concentrations in the Northern Hemisphere (NH) compared with the Southern Hemisphere (SH) for the present-day (2000; inter-hemispheric ratios of 1.13 to 1.42), in contrast to observation-based approaches which generally indicate higher OH in the SH although uncertainties are large. Evaluation of simulated carbon monoxide (CO) concentrations, the primary sink for OH, against ground-based and satellite observations suggests low biases in the NH that may contribute to the high north–south OH asymmetry in the models. The models vary widely in their regional distribution of present-day OH concentrations (up to 34%). Despite large regional changes, the multi-model global mean (mass-weighted) OH concentration changes little over the past 150 yr, due to concurrent increases in factors that enhance OH (humidity, tropospheric ozone, nitrogen oxide (NOx) emissions, and UV radiation due to decreases in stratospheric ozone), compensated by increases in OH sinks (methane abundance, carbon monoxide and non-methane volatile organic carbon (NMVOC) emissions). The large inter-model diversity in the sign and magnitude of preindustrial to present-day OH changes (ranging from a decrease of 12.7% to an increase of 14.6%) indicate that uncertainty remains in our understanding of the long-term trends in OH and methane lifetime. We show that this diversity is largely explained by the different ratio of the

  2. Computing Battery Lifetime Distributions

    NARCIS (Netherlands)

    Cloth, L.; Haverkort, Boudewijn R.H.M.; Jongerden, M.R.

    The usage of mobile devices like cell phones, navigation systems, or laptop computers, is limited by the lifetime of the included batteries. This lifetime depends naturally on the rate at which energy is consumed, however, it also depends on the usage pattern of the battery. Continuous drawing of a

  3. Computing Battery Lifetime Distributions

    NARCIS (Netherlands)

    Cloth, Lucia; Jongerden, Marijn R.; Haverkort, Boudewijn R.

    2007-01-01

    The usage of mobile devices like cell phones, navigation systems, or laptop computers, is limited by the lifetime of the included batteries. This lifetime depends naturally on the rate at which energy is consumed, however, it also depends on the usage pattern of the battery. Continuous drawing of a

  4. Heuristic Optimization of Consumer Electricity Costs Using a Generic Cost Model

    Directory of Open Access Journals (Sweden)

    Chris Ogwumike

    2015-12-01

    Full Text Available Many new demand response strategies are emerging for energy management in smart grids. Real-Time Energy Pricing (RTP is one important aspect of consumer Demand Side Management (DSM, which encourages consumers to participate in load scheduling. This can help reduce peak demand and improve power system efficiency. The use of Intelligent Decision Support Systems (IDSSs for load scheduling has become necessary in order to enable consumers to respond to the changing economic value of energy across different hours of the day. The type of scheduling problem encountered by a consumer IDSS is typically NP-hard, which warrants the search for good heuristics with efficient computational performance and ease of implementation. This paper presents an extensive evaluation of a heuristic scheduling algorithm for use in a consumer IDSS. A generic cost model for hourly pricing is utilized, which can be configured for traditional on/off peak pricing, RTP, Time of Use Pricing (TOUP, Two-Tier Pricing (2TP and combinations thereof. The heuristic greedily schedules controllable appliances to minimize smart appliance energy costs and has a polynomial worst-case computation time. Extensive computational experiments demonstrate the effectiveness of the algorithm and the obtained results indicate the gaps between the optimal achievable costs are negligible.

  5. Predictive models reduce talent development costs in female gymnastics.

    Science.gov (United States)

    Pion, Johan; Hohmann, Andreas; Liu, Tianbiao; Lenoir, Matthieu; Segers, Veerle

    2017-04-01

    This retrospective study focuses on the comparison of different predictive models based on the results of a talent identification test battery for female gymnasts. We studied to what extent these models have the potential to optimise selection procedures, and at the same time reduce talent development costs in female artistic gymnastics. The dropout rate of 243 female elite gymnasts was investigated, 5 years past talent selection, using linear (discriminant analysis) and non-linear predictive models (Kohonen feature maps and multilayer perceptron). The coaches classified 51.9% of the participants correct. Discriminant analysis improved the correct classification to 71.6% while the non-linear technique of Kohonen feature maps reached 73.7% correctness. Application of the multilayer perceptron even classified 79.8% of the gymnasts correctly. The combination of different predictive models for talent selection can avoid deselection of high-potential female gymnasts. The selection procedure based upon the different statistical analyses results in decrease of 33.3% of cost because the pool of selected athletes can be reduced to 92 instead of 138 gymnasts (as selected by the coaches). Reduction of the costs allows the limited resources to be fully invested in the high-potential athletes.

  6. On the reduced lifetime of nitrous oxide due to climate change induced acceleration of the Brewer-Dobson circulation as simulated by the MPI Earth System Model

    Science.gov (United States)

    Kracher, D.; Manzini, E.; Reick, C. H.; Schultz, M. G.; Stein, O.

    2014-12-01

    Greenhouse gas induced climate change will modify the physical conditions of the atmosphere. One of the projected changes is an acceleration of the Brewer-Dobson circulation in the stratosphere, as it has been shown in many model studies. This change in the stratospheric circulation consequently bears an effect on the transport and distribution of atmospheric components such as N2O. Since N2O is involved in ozone destruction, a modified distribution of N2O can be of importance for ozone chemistry. N2O is inert in the troposphere and decays only in the stratosphere. Thus, changes in the exchange between troposphere and stratosphere can also affect the stratospheric sink of N2O, and consequently its atmospheric lifetime. N2O is a potent greenhouse gas with a global warming potential of currently approximately 300 CO2-equivalents in a 100-year perspective. A faster decay in atmospheric N2O mixing ratios, i.e. a decreased atmospheric lifetime of N2O, will also reduce its global warming potential. In order to assess the impact of climate change on atmospheric circulation and implied effects on the distribution and lifetime of atmospheric N2O, we apply the Max Planck Institute Earth System Model, MPI-ESM. MPI-ESM consists of the atmospheric general circulation model ECHAM, the land surface model JSBACH, and MPIOM/HAMOCC representing ocean circulation and ocean biogeochemistry. Prognostic atmospheric N2O concentrations in MPI-ESM are determined by land N2O emissions, ocean-atmosphere N2O exchange and atmospheric tracer transport. As stratospheric chemistry is not explicitly represented in MPI-ESM, stratospheric decay rates of N2O are prescribed from a MACC MOZART simulation. Increasing surface temperatures and CO2 concentrations in the stratosphere impact atmospheric circulation differently. Thus, we conduct a series of transient runs with the atmospheric model of MPI-ESM to isolate different factors governing a shift in atmospheric circulation. From those transient

  7. Computing lifetimes for battery-powered devices

    NARCIS (Netherlands)

    Jongerden, M.R.; Haverkort, Boudewijn R.H.M.

    The battery lifetime of mobile devices depends on the usage pattern of the battery, next to the discharge rate and the battery capacity. Therefore, it is important to include the usage pattern in battery lifetime computations. We do this by combining a stochastic workload, modeled as a

  8. Computing lifetimes for battery-powered devices

    NARCIS (Netherlands)

    Jongerden, Marijn; Haverkort, Boudewijn

    2010-01-01

    The battery lifetime of mobile devices depends on the usage pattern of the battery, next to the discharge rate and the battery capacity. Therefore, it is important to include the usage pattern in battery lifetime computations. We do this by combining a stochastic workload, modeled as a continuous-ti

  9. Proposição de um modelo baseado em Customer Lifetime Value para a análise de melhorias no sistema produtivo Proposition of a Customer Lifetime Value model to evaluate production system improvements

    Directory of Open Access Journals (Sweden)

    Luís Felipe Riehs Camargo

    2011-01-01

    Full Text Available Este artigo propõe um modelo para analisar melhorias no sistema produtivo à luz do valor do cliente para a empresa. Para isso, apresenta um modelo que agrega variáveis advindas do processo produtivo, do mercado consumidor e de métricas do marketing. Os três pilares de sustentação do modelo são os clientes, com suas necessidades e percepções em relação aos produtos e serviços; as características atribuídas pela produção; e as regras para análise do impacto da adoção de diferentes melhorias no sistema produtivo sobre o valor vitalício dos clientes atuais (CLV. Além disso, um modelo de escolha discreta (logit é proposto como o integrador entre a produção e o marketing. O método de pesquisa utilizado foi composto de quatro etapas: levantamento de referencial; construção do modelo conceitual; aplicação em um caso; análise e discussão. Como resultados, observa-se que, havendo disponibilidade de informações e tempo para sua condução, o modelo contribui para a identificação de melhorias que contemplem simultaneamente a visão de produção e a de sustentabilidade financeira.This paper aims to propose a model to investigate the effect of improvements on the productive system on the organization considering customer value. The model proposed combine variables representing the productive process, market, and marketing metrics. It consists of three fundamental elements: consumers and their needs and perceptions of products and services; characteristics of the productive system; and rules to analyze the impact of adoption of different improvements on the productive system. Customer lifetime value (CLV was measured and a discrete choice model (logit is proposed as an integrator between production and marketing perspectives. The research methodology consisted of four steps: referential research, conceptual modeling, application in a particular case, and results analysis. As a result, it is observed that upon availability

  10. Cost models of additive manufacturing: A literature review

    Directory of Open Access Journals (Sweden)

    G. Costabile

    2016-11-01

    Full Text Available From the past decades, increasing attention has been paid to the quality level of technological and mechanical properties achieved by the Additive Manufacturing (AM; these two elements have achieved a good performance, and it is possible to compare this with the results achieved by traditional technology. Therefore, the AM maturity is high enough to let industries adopt this technology in a more general production framework as the mechanical manufacturing industrial one is. Since the technological and mechanical properties are also beneficial for the materials produced with AM, the primary objective of this paper is to focus more on managerial facets, such as the cost control of a production environment, where these new technologies are present. This paper aims to analyse the existing literature about the cost models developed specifically for AM from an operations management point of view and discusses the strengths and weaknesses of all models.

  11. EOQ Model for Time-Deteriorating Items Using Penalty cost

    Directory of Open Access Journals (Sweden)

    Meenakshi Srivastava

    2009-01-01

    Full Text Available In inventory, the utility of the deteriorating items decreases with time. The degree ofdeterioration of product utility can be treated as penalty cost in the inventory replenishmentsystem. In this paper, we present EOQ model for those perishable products, which do notdeteriorate for some period of time and after that time they continuously deteriorate with time andloose their importance. This loss can be incurred as penalty cost to the wholesaler / retailer. Theprime focus of our paper is to develop the EOQ model for time-deteriorating items using penaltycost with finite and infinite production rate. For simplicity, linear and exponential penalty costfunctions have been considered as a measurement of the utility of the product. The theoreticalexpressions are obtained for optimum inventory level and cycle time. All the theoreticaldevelopments are numerically justified.

  12. Polymer damage mitigation---predictive lifetime models of polymer insulation degradation and biorenewable thermosets through cationic polymerization for self-healing applications

    Science.gov (United States)

    Hondred, Peter Raymond

    Over the past 50 years, the industrial development and applications for polymers and polymer composites has become expansive. However, as with any young technology, the techniques for predicting material damage and resolving material failure are in need of continued development and refinement. This thesis work takes two approaches to polymer damage mitigation---material lifetime prediction and spontaneous damage repair through self-healing while incorporating bio-renewable feedstock. First, material lifetime prediction offers the benefit of identifying and isolating material failures before the effects of damage results in catastrophic failure. Second, self-healing provides a systematic approach to repairing damaged polymer composites, specifically in applications where a hands-on approach or removing the part from service are not feasible. With regard to lifetime prediction, we investigated three specific polymeric materials---polytetrafluoroethylene (PTFE), poly(ethylene-alt-tetrafluoroethylene) (ETFE), and Kapton. All three have been utilized extensively in the aerospace field as a wire insulation coating. Because of the vast amount of electrical wiring used in aerospace constructions and the potential for electrical and thermal failure, this work develops mathematical models for both the thermal degradation kinetics as well as a lifetime prediction model for electrothermal breakdown. Isoconversional kinetic methods, which plot activation energy as a function of the extent of degradation, present insight into the development each kinetic model. The models for PTFE, ETFE, and Kapton are one step, consecutive three-step, and competitive and consecutive five-step respectively. Statistical analysis shows that an nth order autocatalytic reaction best defined the reaction kinetics for each polymer's degradation. Self-healing polymers arrest crack propagation through the use of an imbedded adhesive that reacts when cracks form. This form of damage mitigation focuses on

  13. High-spin states and lifetimes in 33S and shell-model interpretation in the s d -f p space

    Science.gov (United States)

    Aydin, S.; Ionescu-Bujor, M.; Gavrilov, G. Tz.; Dimitrov, B. I.; Lenzi, S. M.; Recchia, F.; Tonev, D.; Bouhelal, M.; Kavillioglu, F.; Pavlov, P.; Bazzacco, D.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; de Angelis, G.; Deloncle, I.; Farnea, E.; Gadea, A.; Gottardo, A.; Goutev, N.; Haas, F.; Huyuk, T.; Laftchiev, H.; Lunardi, S.; Marinov, Tz. K.; Mengoni, D.; Menegazzo, R.; Michelagnoli, C.; Napoli, D. R.; Petkov, P.; Sahin, E.; Singh, P. P.; Stefanova, E. A.; Ur, C. A.; Valiente-Dobón, J. J.; Yavahchova, M. S.

    2017-08-01

    The structure of the 33S nucleus was investigated in the 24Mg(14N,α p ) fusion-evaporation reaction using a 40-MeV 14N beam. The level scheme was extended up to an excitation energy of 11.7 MeV and spin 19 /2+ . Lifetimes of the intermediate- and high-spin states have been investigated by the Doppler shift attenuation method. Data were compared with different shell-model calculations where effective interactions involving two main shells, the sd and the fp, are used.

  14. A Cost Model for Integrated Logistic Support Activities

    Directory of Open Access Journals (Sweden)

    M. Elena Nenni

    2013-01-01

    Full Text Available An Integrated Logistic Support (ILS service has the objective of improving a system’s efficiency and availability for the life cycle. The system constructor offers the service to the customer, and she becomes the Contractor Logistic Support (CLS. The aim of this paper is to propose an approach to support the CLS in the budget formulation. Specific goals of the model are the provision of the annual cost of ILS activities through a specific cost model and a comprehensive examination of expected benefits, costs and savings under alternative ILS strategies. A simple example derived from an industrial application is also provided to illustrate the idea. Scientific literature is lacking in the topic and documents from the military are just dealing with the issue of performance measurement. Moreover, they are obviously focused on the customer’s perspective. Other scientific papers are general and focused only on maintenance or life cycle management. The model developed in this paper approaches the problem from the perspective of the CLS, and it is specifically tailored on the main issues of an ILS service.

  15. Modelling User-Costs in Life Cycle Cost-Benefit (LCCB) analysis

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    2008-01-01

    The importance of including user's costs in Life-Cycle Cost-Benefit analysis of structures is discussed in this paper. This is especially for bridges of great importance. Repair or/and failure of a bridge will usually result in user costs greater than the repair or replacement costs of the bridge...

  16. 无线传感器网络最大生命期通信模型研究%Maximum lifetime communication model of wireless sensor network

    Institute of Scientific and Technical Information of China (English)

    尚兴宏; 钱焕延; 高德民

    2011-01-01

    This paper presented a new maximum lifetime communication model of wireless sensor network. Discussed the maximum lifetime of wireless sensor network with multiple sources, multiple paths, multiple sinks deeply. It delivered the data generated by source node to multiple paths and reached multiple sinks in order to balance the flow distribution. According to the energy constraints and data traffic conservation of wireless sensor networks, formulated the problem as a liner program (IP) problem by maximizing the lifetime at which the first node ran out of energy and reduced the amount of data passing the node for the suboptimal goal. Relying on the optimization of a distributed algorithm, the IP could be resolved. It verified the per-formance of communication model in multi-base station environment by simulation. The result shows that the network lifetime can be maximized in communication model.%提出一种新的无线传感器网络最大生命期通信模型,研究了无线传感器网络中多源多链路多基站的最大生命期问题.为均衡数据流量分布,源节点产生的数据可以通过多条链路转发到多个基站.针对无线传感器网络能量和带宽受限等多约束条件,建立以网络最大生命期为最优目标和以降低节点处的数据量为次优目标的线性规划模型,依靠现有的分布式算法解决该模型.通过仿真实验验证了通信模型在多基站环境中的性能,并表明所提出的模型能够有效地延长网络生命期.

  17. The Software Costs Estimation Based on UML Model

    Institute of Scientific and Technical Information of China (English)

    XiaopingYang; LuJun; YuefengZhao

    2004-01-01

    UML is a standard modeling language used in object-oriented analysis and design. Function point analysis is a method used to measure the size of an application, It is independent of the implementation programming language. Its measuring result can be compared between different development processes. This paper presents a method to use the requirements analysis model of UML to analysis the application's function points, so software developer can use it to estimate the project's size and cost. An improved method is given at the end of this paper.

  18. Modelled Cost-Effectiveness of a Package Size Cap and a Kilojoule Reduction Intervention to Reduce Energy Intake from Sugar-Sweetened Beverages in Australia.

    Science.gov (United States)

    Crino, Michelle; Herrera, Ana Maria Mantilla; Ananthapavan, Jaithri; Wu, Jason H Y; Neal, Bruce; Lee, Yong Yi; Zheng, Miaobing; Lal, Anita; Sacks, Gary

    2017-09-06

    Interventions targeting portion size and energy density of food and beverage products have been identified as a promising approach for obesity prevention. This study modelled the potential cost-effectiveness of: a package size cap on single-serve sugar sweetened beverages (SSBs) >375 mL ( package size cap ), and product reformulation to reduce energy content of packaged SSBs ( energy reduction ). The cost-effectiveness of each intervention was modelled for the 2010 Australia population using a multi-state life table Markov model with a lifetime time horizon. Long-term health outcomes were modelled from calculated changes in body mass index to their impact on Health-Adjusted Life Years (HALYs). Intervention costs were estimated from a limited societal perspective. Cost and health outcomes were discounted at 3%. Total intervention costs estimated in AUD 2010 were AUD 210 million. Both interventions resulted in reduced mean body weight ( package size cap : 0.12 kg; energy reduction : 0.23 kg); and HALYs gained ( package size cap : 73,883; energy reduction : 144,621). Cost offsets were estimated at AUD 750.8 million ( package size cap ) and AUD 1.4 billion ( energy reduction ). Cost-effectiveness analyses showed that both interventions were "dominant", and likely to result in long term cost savings and health benefits. A package size cap and kJ reduction of SSBs are likely to offer excellent "value for money" as obesity prevention measures in Australia.

  19. Lifetime of organic photovoltaics

    DEFF Research Database (Denmark)

    Corazza, Michael; Krebs, Frederik C; Gevorgyan, Suren A.

    2015-01-01

    A comprehensive outdoor study of polymer solar cells and modules for duration of one year was conducted. Different sample geometries and encapsulations were employed in order to study the spread in the lifetimes. The study is a complimentary report to previous work that focused on indoor ageing...... tests. Comparison of the indoor and outdoor lifetimes was performed by means of the o-diagram, which constitutes the initial steps towards establishing a method for predicting the lifetime of an organic photovoltaic device under real operational conditions based on a selection of accelerated indoor...

  20. Modelling the cost-effectiveness of public awareness campaigns for the early detection of non-small-cell lung cancer

    Science.gov (United States)

    Hinde, S; McKenna, C; Whyte, S; Peake, M D; Callister, M E J; Rogers, T; Sculpher, M

    2015-01-01

    Background: Survival rates in lung cancer in England are significantly lower than in many similar countries. A range of Be Clear on Cancer (BCOC) campaigns have been conducted targeting lung cancer and found to improve the proportion of diagnoses at the early stage of disease. This paper considers the cost-effectiveness of such campaigns, evaluating the effect of both the regional and national BCOC campaigns on the stage distribution of non-small-cell lung cancer (NSCLC) at diagnosis. Methods: A natural history model of NSCLC was developed using incidence data, data elicited from clinical experts and model calibration techniques. This structure is used to consider the lifetime cost and quality-adjusted survival implications of the early awareness campaigns. Incremental cost-effectiveness ratios (ICERs) in terms of additional costs per quality-adjusted life-years (QALYs) gained are presented. Two scenario analyses were conducted to investigate the role of changes in the ‘worried-well' population and the route of diagnosis that might occur as a result of the campaigns. Results: The base-case theoretical model found the regional and national early awareness campaigns to be associated with QALY gains of 289 and 178 QALYs and ICERs of £13 660 and £18 173 per QALY gained, respectively. The scenarios found that increases in the ‘worried-well' population may impact the cost-effectiveness conclusions. Conclusions: Subject to the available evidence, the analysis suggests that early awareness campaigns in lung cancer have the potential to be cost-effective. However, significant additional research is required to address many of the limitations of this study. In addition, the estimated natural history model presents previously unavailable estimates of the prevalence and rate of disease progression in the undiagnosed population. PMID:26010412

  1. Advanced fuel cycle cost estimation model and its cost estimation results for three nuclear fuel cycles using a dynamic model in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sungki, E-mail: sgkim1@kaeri.re.kr [Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Ko, Wonil [Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Youn, Saerom; Gao, Ruxing [University of Science and Technology, 217 Gajungro, Yuseong-gu, Daejeon 305-350 (Korea, Republic of); Bang, Sungsig, E-mail: ssbang@kaist.ac.kr [Korea Advanced Institute of Science and Technology, Department of Business and Technology Management, 291 Deahak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2015-11-15

    Highlights: • The nuclear fuel cycle cost using a new cost estimation model was analyzed. • The material flows of three nuclear fuel cycle options were calculated. • The generation cost of once-through was estimated to be 66.88 mills/kW h. • The generation cost of pyro-SFR recycling was estimated to be 78.06 mills/kW h. • The reactor cost was identified as the main cost driver of pyro-SFR recycling. - Abstract: The present study analyzes advanced nuclear fuel cycle cost estimation models such as the different discount rate model and its cost estimation results. To do so, an analysis of the nuclear fuel cycle cost of three options (direct disposal (once through), PWR–MOX (Mixed OXide fuel), and Pyro-SFR (Sodium-cooled Fast Reactor)) from the viewpoint of economic sense, focusing on the cost estimation model, was conducted using a dynamic model. From an analysis of the fuel cycle cost estimation results, it was found that some cost gap exists between the traditional same discount rate model and the advanced different discount rate model. However, this gap does not change the priority of the nuclear fuel cycle option from the viewpoint of economics. In addition, the fuel cycle costs of OT (Once-Through) and Pyro-SFR recycling based on the most likely value using a probabilistic cost estimation except for reactor costs were calculated to be 8.75 mills/kW h and 8.30 mills/kW h, respectively. Namely, the Pyro-SFR recycling option was more economical than the direct disposal option. However, if the reactor cost is considered, the economic sense in the generation cost between the two options (direct disposal vs. Pyro-SFR recycling) can be changed because of the high reactor cost of an SFR.

  2. Parabolic Trough Reference Plant for Cost Modeling with the Solar Advisor Model (SAM)

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, C.

    2010-07-01

    This report describes a component-based cost model developed for parabolic trough solar power plants. The cost model was developed by the National Renewable Energy Laboratory (NREL), assisted by WorleyParsons Group Inc., for use with NREL's Solar Advisor Model (SAM). This report includes an overview and explanation of the model, two summary contract reports from WorleyParsons, and an Excel spreadsheet for use with SAM. The cost study uses a reference plant with a 100-MWe capacity and six hours of thermal energy storage. Wet-cooling and dry-cooling configurations are considered. The spreadsheet includes capital and operating cost by component to allow users to estimate the impact of changes in component costs.

  3. Renewable Energy Cost Modeling: A Toolkit for Establishing Cost-Based Incentives in the United States; March 2010 -- March 2011

    Energy Technology Data Exchange (ETDEWEB)

    Gifford, J. S.; Grace, R. C.; Rickerson, W. H.

    2011-05-01

    This report is intended to serve as a resource for policymakers who wish to learn more about establishing cost-based incentives. The report will identify key renewable energy cost modeling options, highlight the policy implications of choosing one approach over the other, and present recommendations on the optimal characteristics of a model to calculate rates for cost-based incentives, feed-in tariffs (FITs), or similar policies. These recommendations will be utilized in designing the Cost of Renewable Energy Spreadsheet Tool (CREST). Three CREST models will be publicly available and capable of analyzing the cost of energy associated with solar, wind, and geothermal electricity generators. The CREST models will be developed for use by state policymakers, regulators, utilities, developers, and other stakeholders to assist them in current and future rate-setting processes for both FIT and other renewable energy incentive payment structures and policy analyses.

  4. The cost-effectiveness of neonatal screening for Cystic Fibrosis: an analysis of alternative scenarios using a decision model

    Directory of Open Access Journals (Sweden)

    Tu Karen

    2005-08-01

    Full Text Available Abstract Background The use of neonatal screening for cystic fibrosis is widely debated in the United Kingdom and elsewhere, but the evidence available to inform policy is limited. This paper explores the cost-effectiveness of adding screening for cystic fibrosis to an existing routine neonatal screening programme for congenital hypothyroidism and phenylketonuria, under alternative scenarios and assumptions. Methods The study is based on a decision model comparing screening to no screening in terms of a number of outcome measures, including diagnosis of cystic fibrosis, life-time treatment costs, life years and QALYs gained. The setting is a hypothetical UK health region without an existing neonatal screening programme for cystic fibrosis. Results Under initial assumptions, neonatal screening (using an immunoreactive trypsin/DNA two stage screening protocol costs £5,387 per infant diagnosed, or £1.83 per infant screened (1998 costs. Neonatal screening for cystic fibrosis produces an incremental cost-effectiveness of £6,864 per QALY gained, in our base case scenario (an assumed benefit of a 6 month delay in the emergence of symptoms. A difference of 11 months or more in the emergence of symptoms (and mean survival means neonatal screening is both less costly and produces better outcomes than no screening. Conclusion Neonatal screening is expensive as a method of diagnosis. Neonatal screening may be a cost-effective intervention if the hypothesised delays in the onset of symptoms are confirmed. Implementing both antenatal and neonatal screening would undermine potential economic benefits, since a reduction in the birth incidence of cystic fibrosis would reduce the cost-effectiveness of neonatal screening.

  5. Overwriting information: Correlations, physical costs, and environment models

    Science.gov (United States)

    Anderson, Neal G.

    2012-03-01

    In this sequel to our previous study of the entropic and energetic costs of information erasure [N.G. Anderson, Phys. Lett. A 372 (2008) 5552], we consider direct overwriting of classical information encoded in a quantum-mechanical memory system interacting with a heat bath. Lower bounds on physical costs of overwriting - in both “single-shot” and “sequential” overwriting scenarios - are obtained from globally unitary quantum dynamics and entropic inequalities alone, all within a referential approach that grounds information content in correlations between physical system states. A heterogeneous environment model, required for consistent treatment of sequential overwriting, is introduced and used to establish and relate bounds for various cases.

  6. Mean fluorescence lifetime and its error

    Energy Technology Data Exchange (ETDEWEB)

    Fiserova, Eva [Department of Mathematical Analysis and Applications of Mathematics, Faculty of Science, Palacky University in Olomouc, tr. 17. listopadu 12, CZE-77146 Olomouc (Czech Republic); Kubala, Martin, E-mail: mkubala@prfnw.upol.cz [Department of Biophysics, Faculty of Science, Palacky University in Olomouc, tr. 17. listopadu 12, CZE-77146 Olomouc (Czech Republic)

    2012-08-15

    Mean excited-state lifetime is one of the fundamental fluorescence characteristics and enters as an important parameter into numerous calculations characterizing molecular interactions, such as e.g. FRET or fluorescence quenching. Our experiments demonstrated that the intensity-weighted mean fluorescence lifetime is very robust characteristic, in contrast to the amplitude-weighted one, which value is dependent on the data quality and particularly on the used fitting model. For the first time, we also report the procedure for the error estimation for both the intensity- and amplitude-weighted mean fluorescence lifetimes. Furthermore, we present a method for estimation of the mean fluorescence lifetime directly from the fluorescence-decay curve recorded by TCSPC (Time-Correlated Single-Photon Counting) method. For its simplicity and low computational demands, it could be a useful tool in the high-throughput applications, such as FACS, FLIM-FRET or HPLC detectors. - Highlights: Black-Right-Pointing-Pointer Intensity-weighted mean fluorescence lifetime is very robust characteristic. Black-Right-Pointing-Pointer The amplitude-weighted mean lifetime depends on the selection of fitting model. Black-Right-Pointing-Pointer Rigorous procedure for estimation of confidence intervals for mean lifetime. Black-Right-Pointing-Pointer The mean lifetime can be estimated directly from the TCSPC histogram.

  7. Stochastic Analysis of Orbital Lifetimes of Spacecraft

    Science.gov (United States)

    Sasamoto, Washito; Goodliff, Kandyce; Cornelius, David

    2008-01-01

    A document discusses (1) a Monte-Carlo-based methodology for probabilistic prediction and analysis of orbital lifetimes of spacecraft and (2) Orbital Lifetime Monte Carlo (OLMC)--a Fortran computer program, consisting of a previously developed long-term orbit-propagator integrated with a Monte Carlo engine. OLMC enables modeling of variances of key physical parameters that affect orbital lifetimes through the use of probability distributions. These parameters include altitude, speed, and flight-path angle at insertion into orbit; solar flux; and launch delays. The products of OLMC are predicted lifetimes (durations above specified minimum altitudes) for the number of user-specified cases. Histograms generated from such predictions can be used to determine the probabilities that spacecraft will satisfy lifetime requirements. The document discusses uncertainties that affect modeling of orbital lifetimes. Issues of repeatability, smoothness of distributions, and code run time are considered for the purpose of establishing values of code-specific parameters and number of Monte Carlo runs. Results from test cases are interpreted as demonstrating that solar-flux predictions are primary sources of variations in predicted lifetimes. Therefore, it is concluded, multiple sets of predictions should be utilized to fully characterize the lifetime range of a spacecraft.

  8. Stroboscopic fluorescence lifetime imaging.

    Science.gov (United States)

    Holton, Mark D; Silvestre, Oscar R; Errington, Rachel J; Smith, Paul J; Matthews, Daniel R; Rees, Paul; Summers, Huw D

    2009-03-30

    We report a fluorescence lifetime imaging technique that uses the time integrated response to a periodic optical excitation, eliminating the need for time resolution in detection. A Dirac pulse train of variable period is used to probe the frequency response of the total fluorescence per pulse leading to a frequency roll-off that is dependent on the relaxation rate of the fluorophores. The technique is validated by demonstrating wide-field, realtime, lifetime imaging of the endocytosis of inorganic quantum dots by a cancer cell line. Surface charging of the dots in the intra-cellular environment produces a switch in the fluorescence lifetime from approximately 40 ns to technique offers lifetime based imaging at video rates with standard CCD cameras and has application in probing millisecond cell dynamics and in high throughput imaging assays.

  9. Measuring Lifetime Poverty

    OpenAIRE

    Michael Hoy; Buhong Zheng

    2008-01-01

    This paper presents an axiomatic framework for measuring life time poverty over multiple periods. For an individual, we argue that lifetime poverty is influenced by both the snapshot poverty of each period and the poverty level of the "permanent" lifetime consumption; it is also influenced by how poverty spells are distributed over the life time. Two obvious candidates for aggregation are to aggregate over time and then across individuals, or vice versa. For a society, we consider a path-inde...

  10. Using a Cost-Construction Model To Assess the Cost of Educating Undergraduate Medical Students at the University of Texas-Houston Medical School.

    Science.gov (United States)

    Franzini, Luisa; And Others

    1997-01-01

    Using a cost-construction model, cost of the University of Texas-Houston Medical School program, instructional costs, educational costs, and milieu costs were calculated. Sensitivity analysis revealed the financial effects of various factors, some of which increased and some of which decreased cost. Despite inherent complexities of the method and…

  11. Los Alamos Waste Management Cost Estimation Model; Final report: Documentation of waste management process, development of Cost Estimation Model, and model reference manual

    Energy Technology Data Exchange (ETDEWEB)

    Matysiak, L.M.; Burns, M.L.

    1994-03-01

    This final report completes the Los Alamos Waste Management Cost Estimation Project, and includes the documentation of the waste management processes at Los Alamos National Laboratory (LANL) for hazardous, mixed, low-level radioactive solid and transuranic waste, development of the cost estimation model and a user reference manual. The ultimate goal of this effort was to develop an estimate of the life cycle costs for the aforementioned waste types. The Cost Estimation Model is a tool that can be used to calculate the costs of waste management at LANL for the aforementioned waste types, under several different scenarios. Each waste category at LANL is managed in a separate fashion, according to Department of Energy requirements and state and federal regulations. The cost of the waste management process for each waste category has not previously been well documented. In particular, the costs associated with the handling, treatment and storage of the waste have not been well understood. It is anticipated that greater knowledge of these costs will encourage waste generators at the Laboratory to apply waste minimization techniques to current operations. Expected benefits of waste minimization are a reduction in waste volume, decrease in liability and lower waste management costs.

  12. Modeling Stakeholder/Value Dependency through Mean Failure Cost

    Energy Technology Data Exchange (ETDEWEB)

    Aissa, Anis Ben [University of Tunis, Belvedere, Tunisia; Abercrombie, Robert K [ORNL; Sheldon, Frederick T [ORNL; Mili, Ali [New Jersey Insitute of Technology

    2010-01-01

    In an earlier series of works, Boehm et al. discuss the nature of information system dependability and highlight the variability of system dependability according to stakeholders. In a recent paper, the dependency patterns of this model are analyzed. In our recent works, we presented a stakeholder dependent quantitative security model, where we quantify security for a given stakeholder by the mean of the loss incurred by the stakeholder as a result of security threats. We show how this mean can be derived from the security threat configuration (represented as a vector of probabilities that reflect the likelihood of occurrence of the various security threats). We refer to our security metric as MFC, for Mean Failure Cost. In this paper, we analyze Boehm's model from the standpoint of the proposed metric, and show whether, to what extent, and how our metric addresses the issues raised by Boehm's Stakeholder/Value definition of system dependability.

  13. Improving Power System Modeling. A Tool to Link Capacity Expansion and Production Cost Models

    Energy Technology Data Exchange (ETDEWEB)

    Diakov, Victor [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cole, Wesley [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sullivan, Patrick [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brinkman, Gregory [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-11-01

    Capacity expansion models (CEM) provide a high-level long-term view at the prospects of the evolving power system. In simulating the possibilities of long-term capacity expansion, it is important to maintain the viability of power system operation in the short-term (daily, hourly and sub-hourly) scales. Production-cost models (PCM) simulate routine power system operation on these shorter time scales using detailed load, transmission and generation fleet data by minimizing production costs and following reliability requirements. When based on CEM 'predictions' about generating unit retirements and buildup, PCM provide more detailed simulation for the short-term system operation and, consequently, may confirm the validity of capacity expansion predictions. Further, production cost model simulations of a system that is based on capacity expansion model solution are 'evolutionary' sound: the generator mix is the result of logical sequence of unit retirement and buildup resulting from policy and incentives. The above has motivated us to bridge CEM with PCM by building a capacity expansion - to - production cost model Linking Tool (CEPCoLT). The Linking Tool is built to onset capacity expansion model prescriptions onto production cost model inputs. NREL's ReEDS and Energy Examplar's PLEXOS are the capacity expansion and the production cost models, respectively. Via the Linking Tool, PLEXOS provides details of operation for the regionally-defined ReEDS scenarios.

  14. Validation and Comparison of Carbon Sequestration Project Cost Models with Project Cost Data Obtained from the Southwest Partnership

    Energy Technology Data Exchange (ETDEWEB)

    Robert Lee; Reid Grigg; Brian McPherson

    2011-04-15

    Obtaining formal quotes and engineering conceptual designs for carbon dioxide (CO{sub 2}) sequestration sites and facilities is costly and time-consuming. Frequently, when looking at potential locations, managers, engineers and scientists are confronted with multiple options, but do not have the expertise or the information required to quickly obtain a general estimate of what the costs will be without employing an engineering firm. Several models for carbon compression, transport and/or injection have been published that are designed to aid in determining the cost of sequestration projects. A number of these models are used in this study, including models by J. Ogden, MIT's Carbon Capture and Sequestration Technologies Program Model, the Environmental Protection Agency and others. This report uses the information and data available from several projects either completed, in progress, or conceptualized by the Southwest Regional Carbon Sequestration Partnership on Carbon Sequestration (SWP) to determine the best approach to estimate a project's cost. The data presented highlights calculated versus actual costs. This data is compared to the results obtained by applying several models for each of the individual projects with actual cost. It also offers methods to systematically apply the models to future projects of a similar scale. Last, the cost risks associated with a project of this scope are discussed, along with ways that have been and could be used to mitigate these risks.

  15. A model to forecast data centre infrastructure costs.

    Science.gov (United States)

    Vernet, R.

    2015-12-01

    The computing needs in the HEP community are increasing steadily, but the current funding situation in many countries is tight. As a consequence experiments, data centres, and funding agencies have to rationalize resource usage and expenditures. CC-IN2P3 (Lyon, France) provides computing resources to many experiments including LHC, and is a major partner for astroparticle projects like LSST, CTA or Euclid. The financial cost to accommodate all these experiments is substantial and has to be planned well in advance for funding and strategic reasons. In that perspective, leveraging infrastructure expenses, electric power cost and hardware performance observed in our site over the last years, we have built a model that integrates these data and provides estimates of the investments that would be required to cater to the experiments for the mid-term future. We present how our model is built and the expenditure forecast it produces, taking into account the experiment roadmaps. We also examine the resource growth predicted by our model over the next years assuming a flat-budget scenario.

  16. Evaluation of primary HPV-DNA testing in relation to visual inspection methods for cervical cancer screening in rural China: an epidemiologic and cost-effectiveness modelling study

    Directory of Open Access Journals (Sweden)

    Kang Yoon-Jung

    2011-06-01

    Full Text Available Abstract Background A new lower-cost rapid-throughput human papillomavirus (HPV test (careHPV, Qiagen, Gaithersburg, USA has been shown to have high sensitivity for the detection of high grade cervical intraepithelial neoplasia. Methods We assessed the outcomes and cost-effectiveness of careHPV screening in rural China, compared to visual inspection with acetic acid, when used alone (VIA or in combination with Lugol's iodine (VIA/VILI. Using data on sexual behaviour, test accuracy, diagnostic practices and costs from studies performed in rural China, we estimated the cost-effectiveness ratio (CER and associated lifetime outcomes for once-lifetime and twice-lifetime screening strategies, and for routine screening at 5-yearly, 10-yearly and IARC-recommended intervals. The optimal age range for once-lifetime screening was also assessed. Results For all strategies, the relative ordering of test technologies in reducing cervical cancer incidence and mortality was VIA (least effective; VIA/VILI; careHPV@1.0 pg/ml and careHPV@0.5 pg/ml (most effective. For once-lifetime strategies, maximum effectiveness was achieved if screening occurred between 35-50 years. Assuming a participation rate of ~70%, once-lifetime screening at age 35 years would reduce cancer mortality by 8% (for VIA to 12% (for careHPV@0.5 over the long term, with a CER of US$557 (for VIA to $959 (for careHPV@1.0 per life year saved (LYS compared to no intervention; referenced to a 2008 GDP per capita in Shanxi Province of $2,975. Correspondingly, regular screening with an age-standardised participation rate of 62% (which has been shown to be achievable in this setting would reduce cervical cancer mortality by 19-28% (for 10-yearly screening to 43-54% (using IARC-recommended intervals, with corresponding CERs ranging from $665 (for 10-yearly VIA to $2,269 (for IARC-recommended intervals using careHPV@1.0 per LYS. Conclusions This modelled analysis suggests that primary careHPV screening

  17. A new costing model in hospital management: time-driven activity-based costing system.

    Science.gov (United States)

    Öker, Figen; Özyapıcı, Hasan

    2013-01-01

    Traditional cost systems cause cost distortions because they cannot meet the requirements of today's businesses. Therefore, a new and more effective cost system is needed. Consequently, time-driven activity-based costing system has emerged. The unit cost of supplying capacity and the time needed to perform an activity are the only 2 factors considered by the system. Furthermore, this system determines unused capacity by considering practical capacity. The purpose of this article is to emphasize the efficiency of the time-driven activity-based costing system and to display how it can be applied in a health care institution. A case study was conducted in a private hospital in Cyprus. Interviews and direct observations were used to collect the data. The case study revealed that the cost of unused capacity is allocated to both open and laparoscopic (closed) surgeries. Thus, by using the time-driven activity-based costing system, managers should eliminate the cost of unused capacity so as to obtain better results. Based on the results of the study, hospital management is better able to understand the costs of different surgeries. In addition, managers can easily notice the cost of unused capacity and decide how many employees to be dismissed or directed to other productive areas.

  18. The Impact of a Tax on Sugar-Sweetened Beverages on Health and Health Care Costs: A Modelling Study

    Science.gov (United States)

    Veerman, J. Lennert; Sacks, Gary; Antonopoulos, Nicole; Martin, Jane

    2016-01-01

    This paper aims to estimate the consequences of an additional 20% tax on sugar-sweetened beverages (SSBs) on health and health care expenditure. Participants were adult (aged > = 20) Australians alive in 2010, who were modelled over their remaining lifetime. We used lifetable-based epidemiological modelling to examine the potential impact of a 20% valoric tax on SSBs on total lifetime disability-adjusted life years (DALYs), incidence, prevalence, and mortality of obesity-related disease, and health care expenditure. Over the lifetime of adult Australian alive in 2010, seemingly modest estimated changes in average body mass as a result of the SSB tax translated to gains of 112,000 health-adjusted life years for men (95% uncertainty interval [UI]: 73,000–155,000) and 56,000 (95% UI: 36,000–76,000) for women, and a reduction in overall health care expenditure of AUD609 million (95% UI: 368 million– 870 million). The tax is estimated to reduce the number of new type 2 diabetes cases by approximately 800 per year. Twenty-five years after the introduction of the tax, there would be 4,400 fewer prevalent cases of heart disease and 1,100 fewer persons living with the consequences of stroke, and an estimated 1606 extra people would be alive as a result of the tax. The tax would generate an estimated AUD400 million in revenue each year. Governments should consider increasing the tax on sugared drinks. This would improve population health, reduce health care costs, as well as bring in direct revenue. PMID:27073855

  19. The Impact of a Tax on Sugar-Sweetened Beverages on Health and Health Care Costs: A Modelling Study.

    Science.gov (United States)

    Veerman, J Lennert; Sacks, Gary; Antonopoulos, Nicole; Martin, Jane

    2016-01-01

    This paper aims to estimate the consequences of an additional 20% tax on sugar-sweetened beverages (SSBs) on health and health care expenditure. Participants were adult (aged > = 20) Australians alive in 2010, who were modelled over their remaining lifetime. We used lifetable-based epidemiological modelling to examine the potential impact of a 20% valoric tax on SSBs on total lifetime disability-adjusted life years (DALYs), incidence, prevalence, and mortality of obesity-related disease, and health care expenditure. Over the lifetime of adult Australian alive in 2010, seemingly modest estimated changes in average body mass as a result of the SSB tax translated to gains of 112,000 health-adjusted life years for men (95% uncertainty interval [UI]: 73,000-155,000) and 56,000 (95% UI: 36,000-76,000) for women, and a reduction in overall health care expenditure of AUD609 million (95% UI: 368 million- 870 million). The tax is estimated to reduce the number of new type 2 diabetes cases by approximately 800 per year. Twenty-five years after the introduction of the tax, there would be 4,400 fewer prevalent cases of heart disease and 1,100 fewer persons living with the consequences of stroke, and an estimated 1606 extra people would be alive as a result of the tax. The tax would generate an estimated AUD400 million in revenue each year. Governments should consider increasing the tax on sugared drinks. This would improve population health, reduce health care costs, as well as bring in direct revenue.

  20. Vehicle Lightweighting: Mass Reduction Spectrum Analysis and Process Cost Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, Anthony [IBIS Associates, Inc., Waltham, MA (United States); Hannibal, Ted [IBIS Associates, Inc., Waltham, MA (United States); Raghunathan, Anand [Energetics Inc., Columbia, MD (United States); Ivanic, Ziga [Energetics Inc., Columbia, MD (United States); Clark, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    The U.S. Department of Energy’s Vehicle Technologies Office, Materials area commissioned a study to model and assess manufacturing economics of alternative design and production strategies for a series of lightweight vehicle concepts. In the first two phases of this effort examined combinations of strategies aimed at achieving strategic targets of 40% and a 45% mass reduction relative to a standard North American midsize passenger sedan at an effective cost of $3.42 per pound (lb) saved. These results have been reported in the Idaho National Laboratory report INL/EXT-14-33863 entitled Vehicle Lightweighting: 40% and 45% Weight Savings Analysis: Technical Cost Modeling for Vehicle Lightweighting published in March 2015. The data for these strategies were drawn from many sources, including Lotus Engineering Limited and FEV, Inc. lightweighting studies, U.S. Department of Energy-funded Vehma International of America, Inc./Ford Motor Company Multi-Material Lightweight Prototype Vehicle Demonstration Project, the Aluminum Association Transportation Group, many United States Council for Automotive Research’s/United States Automotive Materials Partnership LLC lightweight materials programs, and IBIS Associates, Inc.’s decades of experience in automotive lightweighting and materials substitution analyses.

  1. Lifetime oriented maintenance planning in the Netherlands

    NARCIS (Netherlands)

    Straub, A.

    2003-01-01

    In this paper we set up a framework for lifetime oriented maintenance planning as an outcome and input for strategic housing stock management. The maintenance planning holds maintenance activities and costs in the longer term. We consider the maintenance planning as a tool to calculate and implement

  2. Costly bilingualism model in a population with one zealot

    CERN Document Server

    Hong, Hyunsuk

    2013-01-01

    We consider a costly bilingualism model in which one can take two strategies in parallel. We investigate how a single zealot triggers the cascading behavior and how the compatibility of the two strategies affects when interacting patterns change. First, the role of the interaction range on the cascading is studied by increasing the range from local to global. We find that people sometimes do not favor to take the superior strategy even though its payoff is higher than that of the inferior one. This is found to be caused by the local interactions rather than the global ones. Applying this model to social networks, we find that the location of the zealot is also important for larger cascading in heterogeneous networks.

  3. Costly bilingualism model in a population with one zealot

    Science.gov (United States)

    Hong, Hyunsuk; Son, Seung-Woo

    2013-08-01

    We consider a costly bilingualism model in which one can take two strategies in parallel. We investigate how a single zealot triggers the cascading behavior and how the compatibility of the two strategies affects when interacting patterns change. First, the role of the interaction range in the cascading is studied by increasing the range from local to global. We find that people sometimes do not favor taking the superior strategy even though its payoff is higher than that of the inferior one. This is found to be caused by the local interactions rather than the global ones. Applying this model to social networks, we find that the location of the zealot is also important for larger cascading in heterogeneous networks.

  4. Digital Avionics Information System (DAIS): Life Cycle Cost Impact Modeling System Reliability, Maintainability, and Cost Model (RMCM)--Description. Users Guide. Final Report.

    Science.gov (United States)

    Goclowski, John C.; And Others

    The Reliability, Maintainability, and Cost Model (RMCM) described in this report is an interactive mathematical model with a built-in sensitivity analysis capability. It is a major component of the Life Cycle Cost Impact Model (LCCIM), which was developed as part of the DAIS advanced development program to be used to assess the potential impacts…

  5. A Lifetime Prediction Method for LEDs Considering Real Mission Profiles

    OpenAIRE

    Qu, Xiaohui; Wang, Huai; Zhan, Xiaoqing; Blaabjerg, Frede; Chung, Henry Shu-Hung

    2017-01-01

    The Light-Emitting Diode (LED) has become a very promising alternative lighting source with the advantages of longer lifetime and higher efficiency than traditional ones. The lifetime prediction of LEDs is important to guide the LED system designers to fulfill the design specifications and to benchmark the cost-competitiveness of different lighting technologies. However, the existing lifetime data released by LED manufacturers or standard organizations are usually applicable only for some spe...

  6. Charm Lifetimes and Mixing

    CERN Document Server

    Cheung, H W K

    2002-01-01

    A review of the latest results on charm lifetimes and D-mixing is presented. The e+e- collider experiments are now able to measure charm lifetimes quite precisely, however comparisons with the latest results from fixed-target experiments show that possible systematic effects could be evident. The new D-mixing results from the B-factories have changed the picture that is emerging. Although the new world averaged value of y_CP is now consistent with zero, there is still a very interesting and favoured scenario if the strong phase difference between the Doubly-Cabibbo-suppressed and the Cabibbo-flavoured D0 -> Kpi decay is large.

  7. Computerized operating cost model for industrial steam generation

    Energy Technology Data Exchange (ETDEWEB)

    Powers, T.D.

    1983-02-01

    Pending EPA regulations, establishing revised emission levels for industrial boilers are perceived to have an effect on the relative costs of steam production technologies. To aid in the comparison of competitive boiler technologies, the Steam Cost Code was developed which provides levelized steam costs reflecting the effects of a number of key steam cost parameters. The Steam Cost Code is a user interactive FORTRAN program designed to operate on a VAX computer system. The program requires the user to input a number of variables describing the design characteristics, capital costs, and operating conditions for a specific boiler system. Part of the input to the Steam Cost Code is the capital cost of the steam production system. The capital cost is obtained from a program called INDCEPT, developed by Oak Ridge National Laboratory under Department of Energy, Morgantown Energy Technology Center sponsorship.

  8. Lifetimes and configuration mixing in 110Cd

    Science.gov (United States)

    Lobach, Yu. N.; Efimov, A. D.; Pasternak, A. A.

    Lifetimes of excited states in 110Cd have been measured by the Doppler shift attenuation method in the reaction (α,2nγ) at Eα= 25 MeV. Lifetime values for 8 states and lifetime limits for 3 states were obtained. The band structures of 110Cd have been interpreted in terms of a modified version of the interacting boson model (IBM + 2 q.p.). The calculations explain well the excitation energies and electromagnetic transition probabilities up to Jπ= 16+, except for the 10+1 state. The structural features are discussed in terms of collective and two quasiparticle excitations.

  9. Estimating the Costs of Educating Handicapped Children: A Resource-Cost Model Approach. Final Report.

    Science.gov (United States)

    Hartman, William T.

    The research described in this report attempts to estimate the costs of providing an appropriate education to all school-aged handicapped children by 1980-81. The study begins by addressing the aspects of special education that will help to predict future costs--patterns of growth to the present, legal and political mandates, the nature of various…

  10. [Training and development of the nursing staff: a model of spread sheet cost].

    Science.gov (United States)

    Jerico, Marli de Carvalho; Castilho, Valéria

    2004-09-01

    This paper presents a model of spread sheet cost for training and development programs to the nursing staff in a hospital organization. Significant items of the total cost have been considered in relation to its elaboration and proper functioning. This model is divided into four parts: Item 1--data related to the training programs; Item 2--direct costs of these programs; Item 3--indirect costs (Continuum Educational Center structure), and Item 4--cost amount. The use of spread sheet cost may provide knowledge and managementfor the nurses and nurse managers. However, the related costs should be reviewed according to each service.

  11. FASTSim: A Model to Estimate Vehicle Efficiency, Cost and Performance

    Energy Technology Data Exchange (ETDEWEB)

    Brooker, A.; Gonder, J.; Wang, L.; Wood, E.; Lopp, S.; Ramroth, L.

    2015-05-04

    The Future Automotive Systems Technology Simulator (FASTSim) is a high-level advanced vehicle powertrain systems analysis tool supported by the U.S. Department of Energy’s Vehicle Technologies Office. FASTSim provides a quick and simple approach to compare powertrains and estimate the impact of technology improvements on light- and heavy-duty vehicle efficiency, performance, cost, and battery batches of real-world drive cycles. FASTSim’s calculation framework and balance among detail, accuracy, and speed enable it to simulate thousands of driven miles in minutes. The key components and vehicle outputs have been validated by comparing the model outputs to test data for many different vehicles to provide confidence in the results. A graphical user interface makes FASTSim easy and efficient to use. FASTSim is freely available for download from the National Renewable Energy Laboratory’s website (see www.nrel.gov/fastsim).

  12. Cost Effective System Modeling of Active Micro- Module Solar Tracker

    Directory of Open Access Journals (Sweden)

    Md. Faisal Shuvo

    2014-01-01

    Full Text Available The increasing interests in using renewable energies are coming from solar thermal energy and solar photovoltaic systems to the micro production of electricity. Usually we already have considered the solar tracking topology in large scale applications like power plants and satellite but most of small scale applications don’t have any solar tracker system, mainly because of its high cost and complex circuit design. From that aspect, this paper confab microcontroller based one dimensional active micro-module solar tracking system, in which inexpensive LDR is used to generate reference voltage to operate microcontroller for functioning the tracking system. This system provides a fast response of tracking system to the parameters like change of light intensity as well as temperature variations. This micro-module model of tracking system can be used for small scale applications like portable electronic devices and running vehicles.

  13. Our Allotted Lifetimes

    Science.gov (United States)

    Gould, Stephen Jay

    1977-01-01

    It is suggested that measured by the internal clock of heartbeats or breathing, all mammals live a similar lifespan. This is based on the fact that mammals, regardless of size, breathe about 200 million times in their lifetime at a rate of 1 breath for every 4 heartbeats. (AJ)

  14. The Cost-Effectiveness of Low-Cost Essential Antihypertensive Medicines for Hypertension Control in China: A Modelling Study.

    Directory of Open Access Journals (Sweden)

    Dongfeng Gu

    2015-08-01

    Full Text Available Hypertension is China's leading cardiovascular disease risk factor. Improved hypertension control in China would result in result in enormous health gains in the world's largest population. A computer simulation model projected the cost-effectiveness of hypertension treatment in Chinese adults, assuming a range of essential medicines list drug costs.The Cardiovascular Disease Policy Model-China, a Markov-style computer simulation model, simulated hypertension screening, essential medicines program implementation, hypertension control program administration, drug treatment and monitoring costs, disease-related costs, and quality-adjusted life years (QALYs gained by preventing cardiovascular disease or lost because of drug side effects in untreated hypertensive adults aged 35-84 y over 2015-2025. Cost-effectiveness was assessed in cardiovascular disease patients (secondary prevention and for two blood pressure ranges in primary prevention (stage one, 140-159/90-99 mm Hg; stage two, ≥160/≥100 mm Hg. Treatment of isolated systolic hypertension and combined systolic and diastolic hypertension were modeled as a reduction in systolic blood pressure; treatment of isolated diastolic hypertension was modeled as a reduction in diastolic blood pressure. One-way and probabilistic sensitivity analyses explored ranges of antihypertensive drug effectiveness and costs, monitoring frequency, medication adherence, side effect severity, background hypertension prevalence, antihypertensive medication treatment, case fatality, incidence and prevalence, and cardiovascular disease treatment costs. Median antihypertensive costs from Shanghai and Yunnan province were entered into the model in order to estimate the effects of very low and high drug prices. Incremental cost-effectiveness ratios less than the per capita gross domestic product of China (11,900 international dollars [Int$] in 2015 were considered cost-effective. Treating hypertensive adults with prior

  15. Economic Competitiveness of U.S. Utility-Scale Photovoltaics Systems in 2015: Regional Cost Modeling of Installed Cost ($/W) and LCOE ($/kWh)

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Ran; James, Ted L.; Chung, Donald; Gagne, Douglas; Lopez, Anthony; Dobos, Aron

    2015-06-14

    Utility-scale photovoltaics (PV) system growth is largely driven by the economic metrics of total installed costs and levelized cost of electricity (LCOE), which differ by region. This study details regional cost factors, including environment (wind speed and snow loads), labor costs, material costs, sales taxes, and permitting costs using a new system-level bottom-up cost modeling approach. We use this model to identify regional all-in PV installed costs for fixed-tilt and one-axis tracker systems in the United States with consideration of union and non-union labor costs in 2015. LCOEs using those regional installed costs are then modeled and spatially presented. Finally, we assess the cost reduction opportunities of increasing module conversion efficiencies on PV system costs in order to indicate the possible economic impacts of module technology advancements and help future research and development (R&D) effects in the context of U.S. SunShot targets.

  16. Lifetime assessment by intermittent inspection under the mixture Weibull power law model with application to XLPE cables.

    Science.gov (United States)

    Hirose, H

    1997-01-01

    This paper proposes a new treatment for electrical insulation degradation. Some types of insulation which have been used under various circumstances are considered to degrade at various rates in accordance with their stress circumstances. The cross-linked polyethylene (XLPE) insulated cables inspected by major Japanese electric companies clearly indicate such phenomena. By assuming that the inspected specimen is sampled from one of the clustered groups, a mixed degradation model can be constructed. Since the degradation of the insulation under common circumstances is considered to follow a Weibull distribution, a mixture model and a Weibull power law can be combined. This is called The mixture Weibull power law model. By using the maximum likelihood estimation for the newly proposed model to Japanese 22 and 33 kV insulation class cables, they are clustered into a certain number of groups by using the AIC and the generalized likelihood ratio test method. The reliability of the cables at specified years are assessed.

  17. Optimal Vehicle Design Using the Integrated System and Cost Modeling Tool Suite

    Science.gov (United States)

    2010-08-01

    Space Vehicle Costing ( ACEIT ) • New Small Sat Model Development & Production Cost O&M Cost Module  Radiation Exposure  Radiation Detector Response...Reliability OML Availability Risk l l Tools CEA, SRM Model, POST, ACEIT , Inflation Model, Rotor Blade Des, Microsoft Project, ATSV, S/1-iABP...space STK, SOAP – Specific mission • Space Vehicle Design (SMAD) • Space Vehicle Propulsion • Orbit Propagation • Space Vehicle Costing ( ACEIT ) • New

  18. Cost Estimates for Designing and Implementing a Novel Team Care Model for Chronically Ill Patients.

    Science.gov (United States)

    Panattoni, Laura; Dillon, Ellis; Hurlimann, Lily; Durbin, Meg; Tai-Seale, Ming

    2017-09-25

    Little is known about the cost of implementing chronic care models. We estimate the human resource cost of implementing a novel team-based chronic care model "Champion," at a large multispecialty group practice. We used activity-based costing to calculate costs from development through rollout and stabilization in 1 clinic with 12 000 chronic care patients. Data analyzed included Microsoft Outlook meeting metadata, supporting documents, and 2014 employee wages. Implementation took more than 29 months, involved 168 employees, and cost the organization $2 304 787. Payers may need to consider a mixed-payment model to support the both implementation and maintenance costs of team-based chronic care.

  19. Molten Salt Power Tower Cost Model for the System Advisor Model (SAM)

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, C. S.; Heath, G. A.

    2013-02-01

    This report describes a component-based cost model developed for molten-salt power tower solar power plants. The cost model was developed by the National Renewable Energy Laboratory (NREL), using data from several prior studies, including a contracted analysis from WorleyParsons Group, which is included herein as an Appendix. The WorleyParsons' analysis also estimated material composition and mass for the plant to facilitate a life cycle analysis of the molten salt power tower technology. Details of the life cycle assessment have been published elsewhere. The cost model provides a reference plant that interfaces with NREL's System Advisor Model or SAM. The reference plant assumes a nominal 100-MWe (net) power tower running with a nitrate salt heat transfer fluid (HTF). Thermal energy storage is provided by direct storage of the HTF in a two-tank system. The design assumes dry-cooling. The model includes a spreadsheet that interfaces with SAM via the Excel Exchange option in SAM. The spreadsheet allows users to estimate the costs of different-size plants and to take into account changes in commodity prices. This report and the accompanying Excel spreadsheet can be downloaded at https://sam.nrel.gov/cost.

  20. Implementation of Remaining Useful Lifetime Transformer Models in the Fleet-Wide Prognostic and Health Management Suite

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Vivek [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lybeck, Nancy J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Pham, Binh [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rusaw, Richard [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Bickford, Randall [Expert Microsystems, Orangevale, CA (United States)

    2015-02-01

    Research and development efforts are required to address aging and reliability concerns of the existing fleet of nuclear power plants. As most plants continue to operate beyond the license life (i.e., towards 60 or 80 years), plant components are more likely to incur age-related degradation mechanisms. To assess and manage the health of aging plant assets across the nuclear industry, the Electric Power Research Institute has developed a web-based Fleet-Wide Prognostic and Health Management (FW-PHM) Suite for diagnosis and prognosis. FW-PHM is a set of web-based diagnostic and prognostic tools and databases, comprised of the Diagnostic Advisor, the Asset Fault Signature Database, the Remaining Useful Life Advisor, and the Remaining Useful Life Database, that serves as an integrated health monitoring architecture. The main focus of this paper is the implementation of prognostic models for generator step-up transformers in the FW-PHM Suite. One prognostic model discussed is based on the functional relationship between degree of polymerization, (the most commonly used metrics to assess the health of the winding insulation in a transformer) and furfural concentration in the insulating oil. The other model is based on thermal-induced degradation of the transformer insulation. By utilizing transformer loading information, established thermal models are used to estimate the hot spot temperature inside the transformer winding. Both models are implemented in the Remaining Useful Life Database of the FW-PHM Suite. The Remaining Useful Life Advisor utilizes the implemented prognostic models to estimate the remaining useful life of the paper winding insulation in the transformer based on actual oil testing and operational data.

  1. [Threshold value for reimbursement of costs of new drugs: cost-effectiveness research and modelling are essential links].

    Science.gov (United States)

    Frederix, Geert W J; Hövels, Anke M; Severens, Johan L; Raaijmakers, Jan A M; Schellens, Jan H M

    2015-01-01

    There is increasing discussion in the Netherlands about the introduction of a threshold value for the costs per extra year of life when reimbursing costs of new drugs. The Medicines Committee ('Commissie Geneesmiddelen'), a division of the Netherlands National Healthcare Institute ('Zorginstituut Nederland'), advises on reimbursement of costs of new drugs. This advice is based upon the determination of therapeutic value of the drug and the results of economic evaluations. Mathematical models that predict future costs and effectiveness are often used in economic evaluations; these models can vary greatly in transparency and quality due to author assumptions. Standardisation of cost-effectiveness models is one solution to overcome the unwanted variation in quality. Discussions about the introduction of a threshold value can only be meaningful if all involved are adequately informed, and by high quality in cost-effectiveness research and, particularly, economic evaluations. Collaboration and discussion between medical specialists, patients or patient organisations, health economists and policy makers, both in development of methods and in standardisation, are essential to improve the quality of decision making.

  2. Modelling the costs of natural hazards in games

    Science.gov (United States)

    Bostenaru-Dan, M.

    2012-04-01

    We will present the application of (socio-)economic models coming from games theory to urban planning and to large scale architectural tasks, the most frequent one presented being that of the church. The importance of games will be seen as a continuation of the role played by toys for the development of skills of the architects. While toys dealt with the development of 3D viewing and more realistic "building" focusing, for example, on details, games use stylized construction management models with "symbols" for resources, being it in a board game or in a computer supported social environment. 22 October 1997 to 31 May 1998 the Canadian Centre of Architecture hosted the exhibition "Toy Town". Apart of architecture toys, a field where principles of city building apply are architecture games. City building games are a subgenre of construction and management games, the best know of each is SimCity. In its initial version of 1989 SimCity included disaster scenarios including the 1906 San Francisco earthquake, but also flooding, fire etc. During the further development only the fire remained as well implemented as the initial scenarios. It was a way to look at the role of disasters in urban planning, not only as way for a new begin, but also as mitigation and earthquake management. It is to be noted that disasters represented in SimCity 2000 are converted to such which develop in surface, such as fire and flood. Earthquake damage which occures at random buildings is not modelled. Also, the fight against the consequences of the disaster, fire and flood are done in a realtime first hand action game, not as construction management game. However, there are costs associated to mitigating the disaster, such as the costs for fire fighters. Today such city building games evolved to 3D applications, the semantic enrichment of which involves the economic model. The digital 3D model will be compared with the "hard copy" 3D model which architecture toys represent. Models for Sim

  3. Quantification of the effect of spatially varying environmental contaminants into a cost model for soil remediation

    NARCIS (Netherlands)

    Broos, J.M.; Aarts, L.; Tooren, C.F.; Stein, A.

    1999-01-01

    In this study we investigated the effects of spatial variability of soil contaminants on cost calculations for soil remediation. Most cost models only provide a single figure, whereas spatial variability is one of the sources to contribute to the uncertainty. A cost model is applied to a study site

  4. Accelerated lifetime testing methodology for lifetime estimation of Lithium-ion batteries used in augmented wind power plants

    DEFF Research Database (Denmark)

    Stroe, Daniel Ioan; Swierczynski, Maciej Jozef; Stan, Ana-Irina

    2013-01-01

    The development of lifetime estimation models for Lithium-ion battery cells, which are working under highly variable mission profiles characteristic for wind power plant applications, requires a lot of expenditures and time resources. Therefore, batteries have to be tested under accelerated...... lifetime ageing conditions. This paper presents a three-stage methodology used for accelerated lifetime testing of Lithium-ion batteries. The results obtained at the end of the accelerated ageing process can be used for the parametrization of a performance-degradation lifetime model. In the proposed...... methodology both calendar and cycling lifetime tests are considered since both components are influencing the lifetime of Lithium-ion batteries. The methodology proposes also a lifetime model verification stage, where Lithium-ion battery cells are tested at normal operating conditions using an application...

  5. Effect of Unequal Lot Sizes, Variable Setup Cost, and Carbon Emission Cost in a Supply Chain Model

    Directory of Open Access Journals (Sweden)

    Biswajit Sarkar

    2015-01-01

    Full Text Available Due to heavy transportation for single-setup multidelivery (SSMD policy in supply chain management, this model assumes carbon emission cost to obtain a realistic behavior for world environment. The transportation for buyer and vendor is considered along with setup cost reduction by using an investment function. It is assumed that the shipment lot size of each delivery is unequal and variable. The buyer inspects all received products and returns defective items to vendor for reworking process. Because of this policy, end customers will only obtain nondefective items. The analytical optimization is considered to obtain the optimum solution of the model. The main goal of this paper is to reduce the total cost by considering carbon emission during the transportation. A numerical example, graphical representation, and sensitivity analysis are given to illustrate the model.

  6. Personality, IQ, and Lifetime Earnings

    DEFF Research Database (Denmark)

    Gensowski, Miriam

    2014-01-01

    Talented individuals are seen as drivers of long-term growth, but how do they realize their full potential? In this paper, I show that lifetime earnings of high-IQ men and women are substantially influenced by their personality traits, in addition to intelligence and education. Personality traits......, as identified in a factor model, significantly affect earnings, but not for young workers. The effects are furthermore heterogeneous by educational attainment. For women, personality traits do not affect family earnings in the same way as own earnings. Personality and IQ also influence earnings indirectly...

  7. Truth-telling and Nash equilibria in minimum cost spanning tree models

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    2012-01-01

    In this paper we consider the minimum cost spanning tree model. We assume that a central planner aims at implementing a minimum cost spanning tree not knowing the true link costs. The central planner sets up a game where agents announce link costs, a tree is chosen and costs are allocated according...... to the rules of the game. We characterize ways of allocating costs such that true announcements constitute Nash equilibria both in case of full and incomplete information. In particular, we find that the Shapley rule based on the irreducible cost matrix is consistent with truthful announcements while a series...

  8. I-RaCM: A Fully Integrated Risk and Lifecycle Cost Model Project

    Data.gov (United States)

    National Aeronautics and Space Administration — SpaceWorks Engineering, Inc. (SEI) proposes development of the Integrated Risk and Cost Model I-RaCM, as the innovation to meet the need for integrated cost and risk...

  9. Utilisation of Modeling, Stress Analysis, Kinematics Optimisation, and Hypothetical Estimation of Lifetime in the Design Process of Mobile Working Machines

    Science.gov (United States)

    Izrael, Gregor; Bukoveczky, Juraj; Gulan, Ladislav

    2011-12-01

    The contribution deals with several methods used in the construction process such as model creation, verification of technical parameters of the machine, and life estimation of the selected modules. Determination of life cycle for mobile working machines, and their carrying modules respectively by investigation and subsequent processing of results gained by service measurements. Machine life claimed by a producer is only relative, because life of these machines depends not only on the way of work on that particular machine but also the state of material which is manipulated by the machine and in great extent the operator, their observance of security regulations, and prescribed working conditions.

  10. A lifetime prediction method for LEDs considering mission profiles

    DEFF Research Database (Denmark)

    Qu, Xiaohui; Wang, Huai; Zhan, Xiaoqing

    2016-01-01

    Light-Emitting Diodes (LEDs) has become a very promising alternative lighting source with the advantages of longer lifetime and higher efficiency than traditional ones. The lifetime prediction of LEDs is important to guide the LED system designers to fulfill the design specifications...... and to benchmark the cost-competitiveness of different lighting technologies. The existing lifetime data released by LED manufacturers or standard organizations are usually applicable only for specific temperature and current levels. Significant lifetime discrepancies may be observed in field operations due...... available from accelerated degradation testing. It identifies also the key variables (e.g., heat sink parameters and lifetime-matching of LED drivers) that can be designed to achieve a specified lifetime and reliability level. Two case studies of an indoor residential lighting and an outdoor street lighting...

  11. Improved Methodology for Developing Cost Uncertainty Models for Naval Vessels

    Science.gov (United States)

    2008-09-01

    correct correlation between elements is necessary to provide the most accurate representation of cost. Many software programs are available for cost...explain what we commonly refer to as the Big Bang. In Greek mythology, Zeus , Poseidon, and Hades rolled dice for parts of the universe. Zeus won the...reliable representation . Reasonable correlation coefficients may provide more realistic and credible estimates of project costs, rather than assuming

  12. Fluorescence lifetime multiplexing with nanocrystals and organic labels.

    Science.gov (United States)

    Grabolle, Markus; Kapusta, Peter; Nann, Thomas; Shu, Xu; Ziegler, Jan; Resch-Genger, Ute

    2009-09-15

    The potential of semiconducting nanocrystals or so-called quantum dots (QDs) for lifetime multiplexing has not been investigated yet, despite the increasing use of QDs in (bio)analytical detection, biosensing, and fluorescence imaging and the obvious need for simple and cost-effective tools and strategies for the simultaneous detection of multiple analytes or events. This is most likely related to their multiexponential decay behavior as for multiplex chromophores, typically monoexponential decay kinetics are requested. The fluorescence decay kinetics of various mixtures of a long-lived, multiexponentially decaying CdSe QD and a short-lived organic dye were analyzed, and a model was developed for the quantification of these labels from the measured complex decay kinetics as a first proof-of-concept for the huge potential of these labels for lifetime multiplexing. In a second step, we evaluated the potential of mixtures of two types of QDs, varying in constituent material to realize distinguishable, yet multiexponential decay kinetics and similar absorption and emission spectra. Strategies for lifetime multiplexing with nanocrystalline labels were derived on the basis of these measurements.

  13. Accurate, low-cost 3D-models of gullies

    Science.gov (United States)

    Onnen, Nils; Gronz, Oliver; Ries, Johannes B.; Brings, Christine

    2015-04-01

    are able to produce accurate and low-cost 3D-models of gullies.

  14. Fort Lincoln School Cost Model and Funding for Comprehensive Plan. Fort Lincoln New Town Education System.

    Science.gov (United States)

    Cohen, Bonnie; And Others

    As part of the overall education plans for Fort Lincoln New Town (FLNT) an automated school cost model was developed. Chapter 1 overviews the FLNT model's features and sets its operational context, while chapter 2 discusses the model in detail. The appendices provide model inputs and cost calculations, names of approximately 500 inputs used in the…

  15. INFORMATION MODEL OF MAJOR DEPRESSION TREATMENT COST - RELEVANCE OF QUALITY MANAGEMENT OF HEALTH SYSTEM

    Directory of Open Access Journals (Sweden)

    Danijela Tadić

    2010-09-01

    Full Text Available This paper develops multirelational data base for major depression costs. It lists how data are collected and stored into the fact base and dimension base. Uncertain data is described linguistically and modelled by fuzzy sets. Linguistic expressions are stored in dimension base. Models of major depression treatment costs are developed for each patient and all population. On the basis of this model and multirelational data base MD-OLAP a model for major depression treatment costs is developed.

  16. A KBE genetic-causal cost modelling methodology for manufacturing cost contingency management

    NARCIS (Netherlands)

    Curran, R.; Gilmour, M.; McAlleean, C.; Kelly, P.

    2009-01-01

    The paper provides validated evidence of a robust methodology for the management of lean manufacturing cost contingency, with a particular focus on contingency regarding recurring work content. A truly concurrent engineering process is established by capturing a range of knowledge from the design, m

  17. A KBE genetic-causal cost modelling methodology for manufacturing cost contingency management

    NARCIS (Netherlands)

    Curran, R.; Gilmour, M.; McAlleean, C.; Kelly, P.

    2009-01-01

    The paper provides validated evidence of a robust methodology for the management of lean manufacturing cost contingency, with a particular focus on contingency regarding recurring work content. A truly concurrent engineering process is established by capturing a range of knowledge from the design,

  18. Utility-Scale Lithium-Ion Storage Cost Projections for Use in Capacity Expansion Models

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Wesley J.; Marcy, Cara; Krishnan, Venkat K.; Margolis, Robert

    2016-11-21

    This work presents U.S. utility-scale battery storage cost projections for use in capacity expansion models. We create battery cost projections based on a survey of literature cost projections of battery packs and balance of system costs, with a focus on lithium-ion batteries. Low, mid, and high cost trajectories are created for the overnight capital costs and the operating and maintenance costs. We then demonstrate the impact of these cost projections in the Regional Energy Deployment System (ReEDS) capacity expansion model. We find that under reference scenario conditions, lower battery costs can lead to increased penetration of variable renewable energy, with solar photovoltaics (PV) seeing the largest increase. We also find that additional storage can reduce renewable energy curtailment, although that comes at the expense of additional storage losses.

  19. Technology commercialization cost model and component case study

    Science.gov (United States)

    1991-12-01

    Fuel cells seem poised to emerge as a clean, efficient, and cost competitive source of fossil fuel based electric power and thermal energy. Sponsors of fuel cell technology development need to determine the validity and the attractiveness of a technology to the market in terms of meeting requirements and providing value which exceeds the total cost of ownership. Sponsors of fuel cell development have addressed this issue by requiring the developers to prepare projections of the future production cost of their fuel cells in commercial quantities. These projected costs, together with performance and life projections, provide a preliminary measure of the total value and cost of the product to the customer. Booz-Allen & Hamilton Inc. and Michael A. Cobb & Company have been retained in several assignments over the years to audit these cost projections. The audits have gone well beyond a simple review of the numbers. They have probed the underlying technical and financial assumptions, the sources of data on material and equipment costs, and explored issues such as the realistic manufacturing yields which can be expected in various processes. Based on the experience gained from these audits, DOE gave Booz-Allen and Michael A. Cobb & company the task to develop a criteria to be used in the execution of future fuel cell manufacturing cost studies. It was thought that such a criteria would make it easier to execute such studies in the future as well as to cause such studies to be more understandable and comparable.

  20. Update on Multi-Variable Parametric Cost Models for Ground and Space Telescopes

    Science.gov (United States)

    Stahl, H. Philip; Henrichs, Todd; Luedtke, Alexander; West, Miranda

    2012-01-01

    Parametric cost models can be used by designers and project managers to perform relative cost comparisons between major architectural cost drivers and allow high-level design trades; enable cost-benefit analysis for technology development investment; and, provide a basis for estimating total project cost between related concepts. This paper reports on recent revisions and improvements to our ground telescope cost model and refinements of our understanding of space telescope cost models. One interesting observation is that while space telescopes are 50X to 100X more expensive than ground telescopes, their respective scaling relationships are similar. Another interesting speculation is that the role of technology development may be different between ground and space telescopes. For ground telescopes, the data indicates that technology development tends to reduce cost by approximately 50% every 20 years. But for space telescopes, there appears to be no such cost reduction because we do not tend to re-fly similar systems. Thus, instead of reducing cost, 20 years of technology development may be required to enable a doubling of space telescope capability. Other findings include: mass should not be used to estimate cost; spacecraft and science instrument costs account for approximately 50% of total mission cost; and, integration and testing accounts for only about 10% of total mission cost.

  1. 78 FR 26269 - Connect America Fund; High-Cost Universal Service Support

    Science.gov (United States)

    2013-05-06

    ... current version of the CAM suggest that this better calibrated approach results in more reliable cost... funding) are roughly 20-25 percent lower in the current version of the CAM than in the cost model... network costs are assets with an accounting lifetime of 20 years or more, such as loop plant,...

  2. Random Supply, Costant Lead Times and Quadratic Backorder Costs. For Inventory Model (M, T)

    OpenAIRE

    Dr. Martin Omorodion

    2014-01-01

    This paper considers the inventory costs for the (M.T) model in which the backorder costs is quadratic, supply is continuous and lead time is constant. Use is made of series 1: Inventory Model (M.T) with quadratic costs and continuous lead times. The inventory cost for fixed M (maximum re-order level) and constant lead times is averaged over the states of M. Supply is assumed to follow a gamma distribution. The inventory costs for the model, random supply, constants lead time and quadratic co...

  3. An EPQ Model with Unit Production Cost and Set-Up Cost as Functions of Production Rate

    Directory of Open Access Journals (Sweden)

    Behrouz Afshar-Nadjafi

    2013-01-01

    Full Text Available Extensive research has been devoted to economic production quantity (EPQ problem. However, no attention has been paid to problems where unit production and set-up costs must be considered as functions of production rate. In this paper, we address the problem of determining the optimal production quantity and rate of production in which unit production and set-up costs are assumed to be continuous functions of production rate. Based on the traditional economic production quantity (EPQ formula, the cost function associated with this model is proved to be nonconvex and a procedure is proposed to solve this problem. Finally, utility of the model is presented using some numerical examples and the results are analyzed.

  4. Life is Short: The Impact of Power States on Base Station Lifetime

    Directory of Open Access Journals (Sweden)

    Luca Chiaraviglio

    2015-12-01

    Full Text Available We study the impact of power state transitions on the lifetime of base stations (BSs in mobile networks. In particular, we propose a model to estimate the lifetime decrease/increase as a consequence of the application of power state changes. The model takes into account both hardware (HW parameters, which depend on the materials used to build the device, and power state parameters, that instead depend on how and when power state transitions take place. More in depth, we consider the impact of different power states when a BS is active, and one sleep mode state when a BS is powered off. When a BS reduces the power consumption, its lifetime tends to increase. However, when a BS changes the power state, its lifetime tends to be decreased. Thus, there is a tradeoff between these two effects. Our results, obtained over universal mobile telecommunication system (UMTS and long term evolution (LTE case studies, indicate the need of a careful management of the power state transitions in order to not deteriorate the BS lifetime, and consequently to not increase the associated reparation/replacement costs.

  5. Towards a Multi-Variable Parametric Cost Model for Ground and Space Telescopes

    Science.gov (United States)

    Stahl, H. Philip; Henrichs, Todd

    2016-01-01

    Parametric cost models can be used by designers and project managers to perform relative cost comparisons between major architectural cost drivers and allow high-level design trades; enable cost-benefit analysis for technology development investment; and, provide a basis for estimating total project cost between related concepts. This paper hypothesizes a single model, based on published models and engineering intuition, for both ground and space telescopes: OTA Cost approximately (X) D(exp (1.75 +/- 0.05)) lambda(exp(-0.5 +/- 0.25) T(exp -0.25) e (exp (-0.04)Y). Specific findings include: space telescopes cost 50X to 100X more ground telescopes; diameter is the most important CER; cost is reduced by approximately 50% every 20 years (presumably because of technology advance and process improvements); and, for space telescopes, cost associated with wavelength performance is balanced by cost associated with operating temperature. Finally, duplication only reduces cost for the manufacture of identical systems (i.e. multiple aperture sparse arrays or interferometers). And, while duplication does reduce the cost of manufacturing the mirrors of segmented primary mirror, this cost savings does not appear to manifest itself in the final primary mirror assembly (presumably because the structure for a segmented mirror is more complicated than for a monolithic mirror).

  6. LHCb: Measurement of $b$-hadron lifetimes at LHCb

    CERN Multimedia

    Amhis, Y

    2014-01-01

    Lifetimes are among the most fundamental properties of elementary particles. Precision Measurements of $b$-hadron lifetimes are an important tool to test theoretical models such as HQET. These models allow to predict various observables related to B-mixing. Using data collected during Run 1 at the LHC, LHCb measured the lifetime of B-decays including a $J/\\psi$ in the final state.

  7. Gated Detection Measurements of Phosphorescence Lifetimes

    Directory of Open Access Journals (Sweden)

    Yordan Kostov

    2004-10-01

    Full Text Available A low-cost, gated system for measurements of phosphorescence lifetimes is presented. An extensive description of the system operating principles and metrological characteristics is given. Remarkably, the system operates without optical filtering of the LED excitation source. A description of a practical system is also given and its performance is discussed. Because the device effectively suppresses high-level background fluorescence and scattered light, it is expected to find wide-spread application in bioprocess, environmental and biomedical fields.

  8. Modelling cost-effectiveness of interrelated emission reduction strategies

    NARCIS (Netherlands)

    Brink, J.C.

    2003-01-01

    Keywords:Environmental pollution; Acidification; Global warming; Agriculture; Abatement cost; Environmental policy interrelations; Ammonia; Nitrous Oxide; MethaneAgriculture is an important source of ammonia, contributing to acidification and eutrophication, as well as emissions of the greenhouse

  9. Modelling cost-effectiveness of interrelated emission reduction strategies

    NARCIS (Netherlands)

    Brink, J.C.

    2003-01-01

    Keywords:Environmental pollution; Acidification; Global warming; Agriculture; Abatement cost; Environmental policy interrelations; Ammonia; Nitrous Oxide; MethaneAgriculture is an important source of ammonia, contributing to acidification and eutrophication, as well as emissions of the greenhouse ga

  10. Determination of the Free Neutron Lifetime

    CERN Document Server

    Bowman, J David; Clayton, S M; Dewey, M S; Fomin, N; Grammer, K B; Greene, G L; Huffman, P R; Holley, A T; Jones, G L; Liu, C -Y; Makela, M; Mendenhall, M P; Morris, C L; Mulholland, J; Nollett, K M; Pattie,, R W; Penttila, S; Ramsey-Musolf, M; Salvat, D J; Saunders, A; Seestrom, S J; Snow, W M; Steyerl, A; Wietfeldt, F E; Young, A R; Yue, A T

    2014-01-01

    We present the status of current US experimental efforts to measure the lifetime of the free neutron by the "beam" and "bottle" methods. BBN nucleosynthesis models require accurate measurements with 1 second uncertainties, which are currently feasible. For tests of physics beyond the standard model, future efforts will need to achieve uncertainties well below 1 second. We outline paths achieve both.

  11. Cost/effectiveness model of dabigatran in the prevention of venous thromboembolism in major orthopedic surgery: Adaptation for Italy

    Directory of Open Access Journals (Sweden)

    Orietta Zaniolo

    2010-06-01

    Full Text Available Venous thromboembolic events (VTE represent a dangerous complication of major orthopedic surgery, especially in total hip replacement (THR and total knee replacement (TKR procedures. Dabigatran etexilate (DBG, a direct and reversible thrombin inhibitor, has proven its non-inferiority with respect to enoxaparin 40mg once-daily, a low molecular weight heparin (LMWH, in the prevention of VTE in patients undergoing THR and TKR, in the RE-NOVATE and RE-MODEL trials, respectively. The objective of this analysis was to estimate cost/effectiveness and cost/utility of DBG compared to standard care for the prevention of VTE in Italy. A decision analytic, Markov-chain based model, originally developed for the UK, was adapted to the Italian context. The adaptation involved cost and demographic characteristics, clinical and utility data were not altered. Costs were taken from national observational studies, where available. Otherwise, current prices and tariffs were applied. Resource consumption was derived from practice guidelines or taken from the UK model. According to the prevalent national practice, extended prophylaxis is considered for both surgical procedures. The time horizon of the analysis was patients’ lifetimes. In order to consider different alternatives for drug dispensation and, consequently, National Health Service acquisition costs, alternative scenarios were developed. A further scenario, excluding LMWHs administration costs (“worst-case” scenario, was considered. Compared to LMWHs, DBG was associated with an expected increase of 0.019 life-years (LYs and 0.014 quality-adjusted life-years (QALYs per THR patient and of 0.024 LYs and 0.019 QALYs per TKR patient. DBG-related costs were lower than LMWH in both procedures, with a mean difference ranging from 89 to 116 € for THR, and 107 to 142 for TKR, depending on the LMWH product. Higher acquisition costs for DBG were completely offset and inverted by avoided administration expenses

  12. Customer Focused Product Design Using Integrated Model of Target Costing, Quality Function Deployment and Value Engineering

    Directory of Open Access Journals (Sweden)

    Hossein Rezaei Dolatabadi

    2013-01-01

    Full Text Available Target costing by integrating customer requirements, technical attributes and cost information into the product design phase and eliminating the non-value added functions, plays a vital role in different phases of the product life cycle. Quality Function Deployment (QFD and Value Engineering (VE are two techniques which can be used for applying target costing, successfully. The purpose of this paper is to propose an integrated model of target costing, QFD and VE to explore the role of target costing in managing product costs while promoting quality specifications meeting customers’ needs. F indings indicate that the integration of target costing, QFD and VE is an essential technique in managing the costs of production process. Findings also imply that integration of the three techniques provides a competitive cost advantage to companies.

  13. Cost-effectiveness of interventions for increasing the possession of functioning smoke alarms in households with pre-school children: a modelling study.

    Science.gov (United States)

    Saramago, Pedro; Cooper, Nicola J; Sutton, Alex J; Hayes, Mike; Dunn, Ken; Manca, Andrea; Kendrick, Denise

    2014-05-16

    The UK has one of the highest rates for deaths from fire and flames in children aged 0-14 years compared to other high income countries. Evidence shows that smoke alarms can reduce the risk of fire-related injury but little exists on their cost-effectiveness. We aimed to compare the cost effectiveness of different interventions for the uptake of 'functioning' smoke alarms and consequently for the prevention of fire-related injuries in children in the UK. We carried out a decision model-based probabilistic cost-effectiveness analysis. We used a hypothetical population of newborns and evaluated the impact of living in a household with or without a functioning smoke alarm during the first 5 years of their life on overall lifetime costs and quality of life from a public health perspective. We compared seven interventions, ranging from usual care to more complex interventions comprising of education, free/low cost equipment giveaway, equipment fitting and/or home safety inspection. Education and free/low cost equipment was the most cost-effective intervention with an estimated incremental cost-effectiveness ratio of £34,200 per QALY gained compared to usual care. This was reduced to approximately £4,500 per QALY gained when 1.8 children under the age of 5 were assumed per household. Assessing cost-effectiveness, as well as effectiveness, is important in a public sector system operating under a fixed budget restraint. As highlighted in this study, the more effective interventions (in this case the more complex interventions) may not necessarily be the ones considered the most cost-effective.

  14. Lifetimes and HQE

    CERN Document Server

    Lenz, Alexander

    2014-01-01

    Kolya Uraltsev was one of the inventors of the Heavy Quark Expansion (HQE), that describes inclusive weak decays of hadrons containing heavy quarks and in particular lifetimes. Besides giving a pedagogic introduction to the subject, we review the development and the current status of the HQE, which just recently passed several non-trivial experimental tests with an unprecedented precision. In view of many new experimental results for lifetimes of heavy hadrons, we also update several theory predictions: $\\tau (B^+) / \\tau (B_d) = 1.04^{+0.05}_{-0.01} \\pm 0.02 \\pm 0.01$, $\\tau (B_s) / \\tau (B_d) = 1.001 \\pm 0.002$, $\\tau (\\Lambda_b)/ \\tau (B_d) = 0.935 \\pm 0.054$ and $\\bar {\\tau} (\\Xi_b^0) / \\bar{\\tau} (\\Xi_b^+) = 0.95 \\pm 0.06$. The theoretical precision is currently strongly limited by the unknown size of the non-perturbative matrix elements of four-quark operators, which could be determined with lattice simulations.

  15. Construction cost prediction model for conventional and sustainable college buildings in North America

    Directory of Open Access Journals (Sweden)

    Othman Subhi Alshamrani

    2017-03-01

    Full Text Available The literature lacks in initial cost prediction models for college buildings, especially comparing costs of sustainable and conventional buildings. A multi-regression model was developed for conceptual initial cost estimation of conventional and sustainable college buildings in North America. RS Means was used to estimate the national average of construction costs for 2014, which was subsequently utilized to develop the model. The model could predict the initial cost per square feet with two structure types made of steel and concrete. The other predictor variables were building area, number of floors and floor height. The model was developed in three major stages, such as preliminary diagnostics on data quality, model development and validation. The developed model was successfully tested and validated with real-time data.

  16. A preventive maintenance and minimal repair costs model with interest rate

    Science.gov (United States)

    Lewaherilla, Norisca; Pasaribu, Udjianna S.; Husniah, Hennie; Supriantna, Asep K.

    2016-02-01

    This paper deals with minimal repair and sequential imperfect preventive maintenance (imperfect PM) for a fishing vessel. Failure that occur at random times rectified by minimal repair, result minimal repair cost. We add the downtime cost to modify the cost model previously discussed by Jiang and Murthy (2008). That cost is intended as a cost of losses when the vessel is being repaired. Because of the time value of money, each cost should be subject to interest rate. The performance measure is the minimization of the expected total maintenance cost during a certain period. The decision variables are the number of imperfect PM and the level of preventive actions. We assume the distribution of first failure rate is Weibull and follows a nonhomogeneous Poisson process (NHPP). We give the comparison of maintenance costs between the cost resulting from our model and that from the previous model. The previous model is nested in our model and the result shows that in our model a higher interest rate will increase the maintenance cost.

  17. A life cycle cost economics model for automation projects with uniformly varying operating costs. [applied to Deep Space Network and Air Force Systems Command

    Science.gov (United States)

    Remer, D. S.

    1977-01-01

    The described mathematical model calculates life-cycle costs for projects with operating costs increasing or decreasing linearly with time. The cost factors involved in the life-cycle cost are considered, and the errors resulting from the assumption of constant rather than uniformly varying operating costs are examined. Parameters in the study range from 2 to 30 years, for project life; 0 to 15% per year, for interest rate; and 5 to 90% of the initial operating cost, for the operating cost gradient. A numerical example is presented.

  18. A life cycle cost economics model for automation projects with uniformly varying operating costs. [applied to Deep Space Network and Air Force Systems Command

    Science.gov (United States)

    Remer, D. S.

    1977-01-01

    The described mathematical model calculates life-cycle costs for projects with operating costs increasing or decreasing linearly with time. The cost factors involved in the life-cycle cost are considered, and the errors resulting from the assumption of constant rather than uniformly varying operating costs are examined. Parameters in the study range from 2 to 30 years, for project life; 0 to 15% per year, for interest rate; and 5 to 90% of the initial operating cost, for the operating cost gradient. A numerical example is presented.

  19. Costs of treatment of haemophilia A in Italy: comparison of the use of plasma-derived and recombinant FVIII using a discrete event simulation (DES model

    Directory of Open Access Journals (Sweden)

    Mario Eandi

    2013-06-01

    Full Text Available OBJECTIVE: To simulate haemophilia A (HA real-life management and compare the cost of different treatment strategies, both with plasma-derived and recombinant factor VIII (pdFVIII and rFVIII, respectively, from the perspective of the Italian NHS.METHODS: A discrete event (micro-simulation (DES model was developed to reproduce every possible HA patient clinical pathway: on-demand (OD treatment of bleeding, continuous or discontinuous prophylaxis (PRO with FVIII, inhibitors-tolerance-induction treatment (ITI, surgery in case of severe disability. Patient characteristics, treatment indications and disease evolution were modeled basing on data available in clinical literature in order to represent the actual state of art of HA management. In addition to the baseline scenario, reproducing current HA management, alternative strategies were simulated to explore the impact on the cost borne by the Italian NHS for these patients. Only differential direct sanitary costs were considered in the simulation, with a 3.5% discount rate.RESULTS: Baseline scenario results show difference between patients treated with pdFVIII and those treated with rFVIII: mean lifetime HA patient management cost was estimated at € 1,332,373 with pdFVIII treatment, compared with € 2,013,222 for rFVIII. The saving is due mainly to the lower acquisition cost of pdFVIII. Total medical costs are strongly and positively correlated with HA severity: cost per patient increases from € 86,269 (mild HA to € 1,509,231 (severe HA for patients treated with pdFVIII and from € 147,900 to € 2,621,540 in patients treated with rFVIII. All analyses conducted in the study lead to the conclusion that the use of pdFVIII is much less expensive than rFVIII, but therapeutically equivalent.CONCLUSION: Management of HA patients is complex and difficult to optimize; although involving a limited number of patients, lifetime management costs for the Italian NHS are extremely high. The main

  20. A drug cost model for injuries due to road traffic accidents.

    Directory of Open Access Journals (Sweden)

    Riewpaiboon A

    2008-03-01

    Full Text Available Objective: This study aimed to develop a drug cost model for injuries due to road traffic accidents for patients receiving treatment at a regional hospital in Thailand. Methods: The study was designed as a retrospective, descriptive analysis. The cases were all from road traffic accidents receiving treatment at a public regional hospital in the fiscal year 2004. Results: Three thousand seven hundred and twenty-three road accident patients were included in the study. The mean drug cost per case was USD18.20 (SD=73.49, median=2.36. The fitted drug cost model had an adjusted R2 of 0.449. The positive significant predictor variables of drug costs were prolonged length of stay, age over 30 years old, male, Universal Health Coverage Scheme, time of accident during 18:00-24:00 o’clock, and motorcycle comparing to bus. To forecast the drug budget for 2006, there were two approaches identified, the mean drug cost and the predicted average drug cost. The predicted average drug cost was calculated based on the forecasted values of statistically significant (p<0.05 predictor variables included in the fitted model; predicted total drug cost was USD44,334. Alternatively, based on the mean cost, predicted total drug cost in 2006 was USD63,408. This was 43% higher than the figure based on the predicted cost approach.Conclusions: The planned budget of drug cost based on the mean cost and predicted average cost were meaningfully different. The application of a predicted average cost model could result in a more accurate budget planning than that of a mean statistic approach.

  1. A Universal Lifetime Distribution for Multi-Species Systems

    CERN Document Server

    Murase, Yohsuke; Ito, Nobuyasu; Rikvold, Per Arne

    2015-01-01

    Lifetime distributions of social entities, such as enterprises, products, and media contents, are one of the fundamental statistics characterizing the social dynamics. To investigate the lifetime distribution of mutually interacting systems, simple models having a rule for additions and deletions of entities are investigated. We found a quite universal lifetime distribution for various kinds of inter-entity interactions, and it is well fitted by a stretched-exponential function with an exponent close to 1/2. We propose a "modified Red-Queen" hypothesis to explain this distribution. We also review empirical studies on the lifetime distribution of social entities, and discussed the applicability of the model.

  2. Risk Simulation Modeling of Engineering Cost Based on MATLAB/SIMULINK

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Based on MATLAB/SIMULINK, the paper has proposed cost risk simulation models separately in accordance with the circumstances of correlation and independence between the influential factors of cost risk. The mean, variance and the risk level under the above-mentioned two circumstances have also been compared with a case study. Also the sensitivity analysis of cost risk has been probed into. The result indicates that the model which takes into account correlation is more objective, and the model which ignores the circumstance of correlation normally underestimates the risk level of project cost.

  3. Preventive Maintenance Interval Prediction: a Spare Parts Inventory Cost and Lost Earning Based Model

    Directory of Open Access Journals (Sweden)

    O. A. Adebimpe

    2015-06-01

    Full Text Available In this paper, some preventive maintenance parameters in manufacturing firms were identified and used to develop cost based functions in terms of machine preventive maintenance. The proposed cost based model considers system’s reliability, cost of keeping spare parts inventory and lost earnings in deriving optimal maintenance interval. A case of a manufacturing firm in Nigeria was observed and the data was used to evaluate the model.

  4. MEASURING DRIVERS’ EFFECT IN A COST MODEL BY MEANS OF ANALYSIS OF VARIANCE

    Directory of Open Access Journals (Sweden)

    Maria Elena Nenni

    2013-01-01

    Full Text Available In this study the author goes through with the analysis of a cost model developed for Integrated Logistic Support (ILS activities. By means of ANOVA the evaluation of impact and interaction among cost drivers is done. The predominant importance of organizational factors compared to technical ones is definitely demonstrated. Moreover the paper provides researcher and practitioners with useful information to improve the cost model as well as for budgeting and financial planning of ILS activities.

  5. The application of EOQ and lead time crashing cost models in material with limited life time (Case study: CN-235 Aircraft at PT Dirgantara Indonesia)

    Science.gov (United States)

    Agustina Hidayat, Yosi; Ria Kasanah, Aprilia; Yudhistira, Titah

    2016-02-01

    PT. Dirgantara Indonesia, one of State Owned Enterprises engaging in the aerospace industry, targets to control 30% of world market for light and medium sized aircraft. One type of the aircrafts produced by PT. DI every year is CN-235. Currently, the cost of material procurement reaches 50% of the total cost of production. Material has a variety of characteristics, one of which is having a lifetime. The demand characteristic of the material with expiration for the CN-235 aircraft is deterministic. PT DI does not have any scientific background for its procurement of raw material policy. In addition, there are two methods of transportation used for delivering materials, i.e. by land and air. Each method has different lead time. Inventory policies used in this research are deterministic and probabilistic. Both deterministic and probabilistic single and multi-item inventory policies have order quantity, time to order, reorder point, and lead time as decision variables. The performance indicator for this research is total inventory cost. Inventory policy using the single item EOQ and considering expiration factor inventory results in a reduction in total costs up to 69.58% and multi item results in a decrease in total costs amounted to 71.16%. Inventory policy proposal using the model of a single item by considering expiration factor and lead time crashing cost results in a decrease in total costs amounted to 71.5% and multi item results in a decrease in total costs amounted to 71.62%. Subsequently, wasted expired materials, with the proposed models have been successfully decreased to 95%.

  6. European Union-28: An annualised cost-of-illness model for venous thromboembolism.

    Science.gov (United States)

    Barco, Stefano; Woersching, Alex L; Spyropoulos, Alex C; Piovella, Franco; Mahan, Charles E

    2016-04-01

    Annual costs for venous thromboembolism (VTE) have been defined within the United States (US) demonstrating a large opportunity for cost savings. Costs for the European Union-28 (EU-28) have never been defined. A literature search was conducted to evaluate EU-28 cost sources. Median costs were defined for each cost input and costs were inflated to 2014 Euros (€) in the study country and adjusted for Purchasing Power Parity between EU countries. Adjusted costs were used to populate previously published cost-models based on adult incidence-based events. In the base model, annual expenditures for total, hospital-associated, preventable, and indirect costs were €1.5-2.2 billion, €1.0-1.5 billion, €0.5-1.1 billion and €0.2-0.3 billion, respectively (indirect costs: 12 % of expenditures). In the long-term attack rate model, total, hospital-associated, preventable, and indirect costs were €1.8-3.3 billion, €1.2-2.4 billion, €0.6-1.8 billion and €0.2-0.7 billion (indirect costs: 13 % of expenditures). In the multiway sensitivity analysis, annual expenditures for total, hospital-associated, preventable, and indirect costs were €3.0-8.5 billion, €2.2-6.2 billion, €1.1-4.6 billion and €0.5-1.4 billion (indirect costs: 22 % of expenditures). When the value of a premature life-lost increased slightly, aggregate costs rose considerably since these costs are higher than the direct medical costs. When evaluating the models aggregately for costs, the results suggests total, hospital-associated, preventable, and indirect costs ranging from €1.5-13.2 billion, €1.0-9.7 billion, €0.5-7.3 billion and €0.2-6.1 billion, respectively. Our study demonstrates that VTE costs have a large financial impact upon the EU-28's healthcare systems and that significant savings could be realised if better preventive measures are applied.

  7. Grid Integration of Aggregated Demand Response, Part 2: Modeling Demand Response in a Production Cost Model

    Energy Technology Data Exchange (ETDEWEB)

    Hummon, Marissa [National Renewable Energy Lab. (NREL), Golden, CO (United States); Palchak, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Olsen, Daniel J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kiliccote, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Matson, Nance [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rose, Cody [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dudley, Junqiao [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goli, Sasank [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ma, Ookie [U.S. Dept. of Energy, Washington, DC (United States)

    2013-12-01

    This report is one of a series stemming from the U.S. Department of Energy (DOE) Demand Response and Energy Storage Integration Study. This study is a multi-national-laboratory effort to assess the potential value of demand response (DR) and energy storage to electricity systems with different penetration levels of variable renewable resources and to improve our understanding of associatedmarkets and institutions. This report implements DR resources in the commercial production cost model PLEXOS.

  8. Budgeting Facilities Operation Costs Using the Facilities Operation Model

    Science.gov (United States)

    2011-06-01

    composting are included. Excludes: hazardous, biological, toxic, corrosive, reactive, flammable, radioactive wastes, and construction and demolition...debris resulting from construction contracts. Also excluded are the recycling and composting programs paid by Environmental PEs. 5. Real Property...waxes, toilet tissue, mops, brooms) Accounts for all activities associated with the management and costs for custodial (i.e. carpet cleaning, window

  9. Modeling of manufacturer and retailer cooperative income considering advertising costs

    Directory of Open Access Journals (Sweden)

    A.O. Zavirukha

    2013-03-01

    Full Text Available The paper represents logical block diagram of cooperative advertising costs adjustment in manufacturer and retailers logistics chain. Manufacturer and retailers joint interaction profit is considered provided linear demand function and nonlinear response function of advertising expenditures. Dimensionless variables system is introduced to form cooperative income function.

  10. Cost-effectiveness modelling in diagnostic imaging: a stepwise approach

    NARCIS (Netherlands)

    Sailer, A.M.; Zwam, W.H. van; Wildberger, J.E.; Grutters, J.P.C.

    2015-01-01

    Diagnostic imaging (DI) is the fastest growing sector in medical expenditures and takes a central role in medical decision-making. The increasing number of various and new imaging technologies induces a growing demand for cost-effectiveness analysis (CEA) in imaging technology assessment. In this ar

  11. sensitivity analysis on flexible road pavement life cycle cost model

    African Journals Online (AJOL)

    user

    methods of assessing and managing the risk and uncertainties ... cost studies in flexible pavement delivery, it is important ... developed for the road pavement in the study area as .... vehicle counts per day of 400 of a single carriageway ..... from the Intermodal Terminal” in Sweden, which had ... Company, Malabar, Florida.

  12. The growth limits of the low cost carrier model

    NARCIS (Netherlands)

    de Wit, J.G.; Zuidberg, J.

    2012-01-01

    Today, many low cost carriers (LCCs) continue to enjoy rapid growth and still have a fair number of new aircraft on order. There are signs however that the market for LCCs is limited, owing to increasing route density problems, primarily in Europe but seemingly also in North America: the fact that a

  13. Optimal administrative scale for planning public services: a social cost model applied to Flemish hospital care.

    Science.gov (United States)

    Blank, Jos L T; van Hulst, Bart

    2015-01-01

    In choosing the scale of public services, such as hospitals, both economic and public administrative considerations play important roles. The scale and the corresponding spatial distribution of public institutions have consequences for social costs, defined as the institutions' operating costs and the users' travel costs (which include the money and time costs). Insight into the relationship between scale and spatial distribution and social costs provides a practical guide for the best possible administrative planning level. This article presents a purely economic model that is suitable for deriving the optimal scale for public services. The model also reveals the corresponding optimal administrative planning level from an economic perspective. We applied this model to hospital care in Flanders for three different types of care. For its application, we examined the social costs of hospital services at different levels of administrative planning. The outcomes show that the social costs of rehabilitation in Flanders with planning at the urban level (38 areas) are 11% higher than those at the provincial level (five provinces). At the regional level (18 areas), the social costs of rehabilitation are virtually equal to those at the provincial level. For radiotherapy, there is a difference of 88% in the social costs between the urban and the provincial level. For general care, there are hardly any cost differences between the three administrative levels. Thus, purely from the perspective of social costs, rehabilitation should preferably be planned at the regional level, general services at the urban level and radiotherapy at the provincial level.

  14. Protective effect of Aronia melanocarpa polyphenols against cadmium-induced disorders in bone metabolism: a study in a rat model of lifetime human exposure to this heavy metal.

    Science.gov (United States)

    Brzóska, Malgorzata M; Rogalska, Joanna; Galazyn-Sidorczuk, Malgorzata; Jurczuk, Maria; Roszczenko, Alicja; Tomczyk, Michal

    2015-03-05

    It was investigated, in a female rat model of low and moderate lifetime human exposure to cadmium (Cd), whether polyphenols from Aronia melanocarpa berries (chokeberry; AMP) may offer protection from this heavy metal-induced disorders in bone metabolism. For this purpose, numerous indices of bone formation (osteocalcin, alkaline phosphatase, osteoprotegerin) and resorption (carboxy-terminal cross-linking telopeptides of type I collagen, soluble receptor activator of nuclear factor-κB ligand) in the serum and/or distal femur epiphysis (trabecular bone region), as well as bone mineral status (volumetric bone mineral density of the femur and content of mineral components, including calcium, in the bone tissue at the distal femur epiphysis) were evaluated in female Wistar rats that received a 0.1% aqueous extract of AMP, as the only drinking fluid (prepared from lyophilized extract by Adamed Consumer Healthcare), and/or Cd in diet (1 and 5mg/kg) for 3, 10, 17, and 24 months. Examination of the phytochemical profile of the aronia extract revealed high content of polyphenols (612.40 ± 3.33 mg/g), including anthocyanins, proanthocyanidins, phenolic acids, and flavonoids. Among detected compounds anthocyanins were identified as dominating. The exposure to Cd, dose- and duration-dependently, enhanced resorption and inhibited formation of the bone tissue resulting in its decreased mineralization. The administration of AMP under the exposure to 1 and 5 mgCd/kg diet provided important protection from this heavy metal-induced disturbances in the bone turnover and changes in the bone mineral status, and the beneficial impact of polyphenols resulted from their independent action and interaction with Cd. These findings suggest that consumption of Aronia melanocarpa polyphenols may play a role in prevention against female skeleton damage due to chronic exposure to Cd and that chokeberry represents the good natural plant candidate for further investigations of its prophylactic use

  15. An innovative time-cost-quality tradeoff modeling of building construction project based on resource allocation.

    Science.gov (United States)

    Hu, Wenfa; He, Xinhua

    2014-01-01

    The time, quality, and cost are three important but contradictive objectives in a building construction project. It is a tough challenge for project managers to optimize them since they are different parameters. This paper presents a time-cost-quality optimization model that enables managers to optimize multiobjectives. The model is from the project breakdown structure method where task resources in a construction project are divided into a series of activities and further into construction labors, materials, equipment, and administration. The resources utilized in a construction activity would eventually determine its construction time, cost, and quality, and a complex time-cost-quality trade-off model is finally generated based on correlations between construction activities. A genetic algorithm tool is applied in the model to solve the comprehensive nonlinear time-cost-quality problems. Building of a three-storey house is an example to illustrate the implementation of the model, demonstrate its advantages in optimizing trade-off of construction time, cost, and quality, and help make a winning decision in construction practices. The computational time-cost-quality curves in visual graphics from the case study prove traditional cost-time assumptions reasonable and also prove this time-cost-quality trade-off model sophisticated.

  16. An Innovative Time-Cost-Quality Tradeoff Modeling of Building Construction Project Based on Resource Allocation

    Directory of Open Access Journals (Sweden)

    Wenfa Hu

    2014-01-01

    Full Text Available The time, quality, and cost are three important but contradictive objectives in a building construction project. It is a tough challenge for project managers to optimize them since they are different parameters. This paper presents a time-cost-quality optimization model that enables managers to optimize multiobjectives. The model is from the project breakdown structure method where task resources in a construction project are divided into a series of activities and further into construction labors, materials, equipment, and administration. The resources utilized in a construction activity would eventually determine its construction time, cost, and quality, and a complex time-cost-quality trade-off model is finally generated based on correlations between construction activities. A genetic algorithm tool is applied in the model to solve the comprehensive nonlinear time-cost-quality problems. Building of a three-storey house is an example to illustrate the implementation of the model, demonstrate its advantages in optimizing trade-off of construction time, cost, and quality, and help make a winning decision in construction practices. The computational time-cost-quality curves in visual graphics from the case study prove traditional cost-time assumptions reasonable and also prove this time-cost-quality trade-off model sophisticated.

  17. Development of a risk-based mine closure cost calculation model

    CSIR Research Space (South Africa)

    Du Plessis, A

    2006-06-01

    Full Text Available The study summarised in this paper focused on expanding existing South African mine closure cost calculation models to provide a new model that incorporates risks, which could have an effect on the closure costs during the life cycle of the mine...

  18. The Optimal Solution of the Model with Physical and Human Capital Adjustment Costs

    Institute of Scientific and Technical Information of China (English)

    RAO Lan-lan; CAI Dong-han

    2004-01-01

    We prove that the model with physical and human capital adjustment costs has optimal solution when the production function is increasing return and the structure of vetor fields of the model changes substantially when the prodution function from decreasing return turns to increasing return.And it is shown that the economy is improved when the coefficients of adjustment costs become small.

  19. Costs and effects of chlamydial screening : Dynamic versus static modeling

    NARCIS (Netherlands)

    Welte, R; Postma, M; Leidl, R; Kretzschmar, M

    2005-01-01

    Objective: The objective of this study was to assess the impact of modeling type on the economic evaluation of screening programs for asymptomatic Chlamydia trachomatis infections. Study: We compared a stochastic network simulation model (dynamic model) with a decision analysis model (static model)

  20. Costs and effects of chlamydial screening : Dynamic versus static modeling

    NARCIS (Netherlands)

    Welte, R; Postma, M; Leidl, R; Kretzschmar, M

    2005-01-01

    Objective: The objective of this study was to assess the impact of modeling type on the economic evaluation of screening programs for asymptomatic Chlamydia trachomatis infections. Study: We compared a stochastic network simulation model (dynamic model) with a decision analysis model (static model)

  1. The Calculation Model for Operation Cost of Coal Resources Development Based on ANN

    Institute of Scientific and Technical Information of China (English)

    刘海滨

    2004-01-01

    On the basis of analysis and selection of factors influencing operation cost of coal resources development, fuzzy set method and artificial neural network (ANN) were adopted to set up the classification analysis model of coal resources. The collected samples were classified by using this model. Meanwhile, the pattern recognition model for classifying of the coal resources was built according to the factors influencing operation cost. Based on the results achieved above, in the light of the theory of information diffusion, the calculation model for operation cost of coal resources development has been presented and applied in practice, showing that these models are reasonable.

  2. Lifetime measurement of high spin states in {sup 75}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, T. [Department of Physics, University of Allahabad, Allahabad-211001 (India); Palit, R. [Tata Institute of Fundamental Research, Mumbai-400005 (India); Negi, D. [Inter University Accelerator Centre, New Delhi-110067 (India); Naik, Z. [Tata Institute of Fundamental Research, Mumbai-400005 (India); Yang, Y.-C. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Sun, Y. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Sheikh, J.A. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Physics Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831 (United States); Department of Physics, University of Kashmir, Srinagar 190 006 (India); Dhal, A. [Department of Physics, Banaras Hindu University, Varanasi 221005 (India); Raju, M.K. [Department of Nuclear Physics, Andhra University, Visakhapatnam-530003 (India); Appannababu, S. [Department of Physics, MS University of Baroda, Vadodara-390002 (India); Kumar, S. [Department of Physics and Astrophysics, University of Delhi, Delhi-110007 (India); Choudhury, D. [Department of Physics, IIT Roorkee, Roorkee-247667 (India); Maurya, K. [Department of Physics, University of Allahabad, Allahabad-211001 (India); Mahanto, G.; Kumar, R.; Singh, R.P.; Muralithar, S. [Inter University Accelerator Centre, New Delhi-110067 (India); Jain, A.K. [Department of Physics, IIT Roorkee, Roorkee-247667 (India); Jain, H.C. [Tata Institute of Fundamental Research, Mumbai-400005 (India); Pancholi, S.C. [Inter University Accelerator Centre, New Delhi-110067 (India)

    2010-03-01

    The lifetimes of high spin states of {sup 75}Kr have been determined via {sup 50}Cr ({sup 28}Si, 2pn) {sup 75}Kr reaction in positive parity band using the Doppler-shift attenuation method. The transition quadrupole moments Q{sub t} deduced from lifetime measurements have been compared with {sup 75}Br. Experimental results obtained from lifetime measurement are interpreted in the framework of projected shell model.

  3. Model-based cost-effectiveness analysis of B-type natriuretic peptide-guided care in patients with heart failure

    Science.gov (United States)

    Mohiuddin, Syed; Reeves, Barnaby; Pufulete, Maria; Maishman, Rachel; Dayer, Mark; Macleod, John; McDonagh, Theresa; Purdy, Sarah; Rogers, Chris; Hollingworth, William

    2016-01-01

    Objective Monitoring B-type natriuretic peptide (BNP) to guide pharmacotherapy might improve survival in patients with heart failure with reduced ejection fraction (HFrEF) or preserved ejection fraction (HFpEF). However, the cost-effectiveness of BNP-guided care is uncertain and guidelines do not uniformly recommend it. We assessed the cost-effectiveness of BNP-guided care in patient subgroups defined by age and ejection fraction. Methods We used a Markov model with a 3-month cycle length to estimate the lifetime health service costs, quality-adjusted life years (QALYs) and incremental net monetary benefits (iNMBs) of BNP-guided versus clinically guided care in 3 patient subgroups: (1) HFrEF patients HFpEF patients HFpEF aged ≥75 years. We used individual patient data meta-analyses and linked primary care, hospital and mortality data to inform the key model parameters. We performed probabilistic analysis to assess the uncertainty in model results. Results In younger patients (HFpEF (£3155 (−£10 307 to £11 613)) and older patients (≥75 years) with HFrEF (£2267 (−£1524 to £6074)). BNP-guided care remained cost-effective in the sensitivity analyses, albeit the results were sensitive to assumptions on its sustained effect. Conclusions We found strong evidence that BNP-guided care is a cost-effective alternative to clinically guided care in younger patients with HFrEF. It is potentially cost-effective in younger patients with HFpEF and older patients with HFrEF, but more evidence is required, particularly with respect to the frequency, duration and BNP target for monitoring. Cost-effectiveness results from trials in specialist settings cannot be generalised to primary care. PMID:28031211

  4. Personality, IQ, and Lifetime Earnings

    DEFF Research Database (Denmark)

    Gensowski, Miriam

    2014-01-01

    , as identified in a factor model, significantly affect earnings, but not for young workers. The effects are furthermore heterogeneous by educational attainment. For women, personality traits do not affect family earnings in the same way as own earnings. Personality and IQ also influence earnings indirectly...... through education, which has sizeable positive rates of return for men in this sample. Women’s returns to education past a bachelor’s degree are lowered through worse marriage prospects, which offset gains to education in terms of own earnings. The causal effect of education is identified through matching......Talented individuals are seen as drivers of long-term growth, but how do they realize their full potential? In this paper, I show that lifetime earnings of high-IQ men and women are substantially influenced by their personality traits, in addition to intelligence and education. Personality traits...

  5. FLUORESCENCE LIFETIME DISTRIBUTIONS IN PROTEINS

    OpenAIRE

    ALCALA, JR; Gratton, E; PRENDERGAST, FG

    1987-01-01

    The fluorescence lifetime value of tryptophan residues varies by more than a factor of 100 in different proteins and is determined by several factors, which include solvent exposure and interactions with other elements of the protein matrix. Because of the variety of different elements that can alter the lifetime value and the sensitivity to the particular environment of the tryptophan residue, it is likely that non-unique lifetime values result in protein systems. The emission decay of most ...

  6. A model for the inverse 1-median problem on trees under uncertain costs

    Directory of Open Access Journals (Sweden)

    Kien Trung Nguyen

    2016-01-01

    Full Text Available We consider the problem of justifying vertex weights of a tree under uncertain costs so that a prespecified vertex become optimal and the total cost should be optimal in the uncertainty scenario. We propose a model which delivers the information about the optimal cost which respect to each confidence level \\(\\alpha \\in [0,1]\\. To obtain this goal, we first define an uncertain variable with respect to the minimum cost in each confidence level. If all costs are independently linear distributed, we present the inverse distribution function of this uncertain variable in \\(O(n^{2}\\log n\\ time, where \\(n\\ is the number of vertices in the tree.

  7. A MCM modeling study of the effects of nitryl chloride on oxidant budgets, ozone production, VOC lifetimes, and halogen recycling in polluted regions

    Science.gov (United States)

    Riedel, T. P.; Thornton, J. A.; Wolfe, G. M.; Gilman, J. B.; Kuster, W. C.; De Gouw, J. A.; Bon, D.; Vlasenko, A. L.; Li, S.; Williams, E. J.; Lerner, B. M.; Veres, P. R.; Roberts, J. M.

    2012-12-01

    Nitryl chloride (ClNO2) is produced at night by reactions of dinitrogen pentoxide (N2O5) on chloride containing particles. Nitryl chloride is photolyzed during the day to liberate highly reactive chlorine atoms. This chemistry takes place primarily in urban environments where the concentrations of N2O5 precursors (NOx and ozone) are high, though it can likely occur in remote regions at lower intensity. Recent field measurements have illustrated the potential importance of ClNO2 as a chlorine atom source and a NOx reservoir. However, the fate of these chlorine atoms and the overall impact of ClNO2 remain unclear. To this end we have incorporated ClNO2 production, photolysis, and subsequent Cl-atom reactions into an existing Master Chemical Mechanism (MCM version 3.2) based model framework. Cl-atom reactions with alkenes and alcohols not presently part of the MCM have also been added. Using observational constraints from the CalNex 2010 field study, we assess the dominant reactive sinks and sources of chlorine atoms over the course of a model day. Relative to model runs excluding ClNO2 formation, the presence of ClNO2 produces marked changes on a variety of species important to tropospheric chemistry and air quality (e.g. O3, RO2, OH, HO2, ClOx). For example a 50% yield of ClNO2 (max ClNO2 of 1.5 ppb) from nighttime N2O5 reactions leads to a ~10% enhancement in integrated ozone production. VOC and NOx lifetimes are shorter due primarily to enhanced OH from propagation of RO2 produced by Cl-atom chemistry under high NOx. The impact of ClNO2 on daytime halogen atom recycling is substantial, with order of magnitude higher daytime Cl2 production predicted with ClNO2 chemistry than without. In fact, incorporation of ClNO2 could help explain daytime levels of Cl2 observed in polluted coastal regions. Additionally, we highlight a set of chlorinated VOC oxidation products that are predicted to form at small, but potentially detectable levels in regions with similar VOC

  8. Cubosomes for in vivo fluorescence lifetime imaging

    Science.gov (United States)

    Biffi, Stefania; Andolfi, Laura; Caltagirone, Claudia; Garrovo, Chiara; Falchi, Angela M.; Lippolis, Vito; Lorenzon, Andrea; Macor, Paolo; Meli, Valeria; Monduzzi, Maura; Obiols-Rabasa, Marc; Petrizza, Luca; Prodi, Luca; Rosa, Antonella; Schmidt, Judith; Talmon, Yeshayahu; Murgia, Sergio

    2017-02-01

    Herein we provided the first proof of principle for in vivo fluorescence optical imaging application using monoolein-based cubosomes in a healthy mouse animal model. This formulation, administered at a non-cytotoxic concentration, was capable of providing both exogenous contrast for NIR fluorescence imaging with very high efficiency and chemospecific information upon lifetime analysis. Time-resolved measurements of fluorescence after the intravenous injection of cubosomes revealed that the dye rapidly accumulated mainly in the liver, while lifetimes profiles obtained in vivo allowed for discriminating between free dye or dye embedded within the cubosome nanostructure after injection.

  9. Cubosomes for in vivo fluorescence lifetime imaging.

    Science.gov (United States)

    Biffi, Stefania; Andolfi, Laura; Caltagirone, Claudia; Garrovo, Chiara; Falchi, Angela M; Lippolis, Vito; Lorenzon, Andrea; Macor, Paolo; Meli, Valeria; Monduzzi, Maura; Obiols-Rabasa, Marc; Petrizza, Luca; Prodi, Luca; Rosa, Antonella; Schmidt, Judith; Talmon, Yeshayahu; Murgia, Sergio

    2017-02-03

    Herein we provided the first proof of principle for in vivo fluorescence optical imaging application using monoolein-based cubosomes in a healthy mouse animal model. This formulation, administered at a non-cytotoxic concentration, was capable of providing both exogenous contrast for NIR fluorescence imaging with very high efficiency and chemospecific information upon lifetime analysis. Time-resolved measurements of fluorescence after the intravenous injection of cubosomes revealed that the dye rapidly accumulated mainly in the liver, while lifetimes profiles obtained in vivo allowed for discriminating between free dye or dye embedded within the cubosome nanostructure after injection.

  10. Lifetime-weighted photoacoustic imaging

    Science.gov (United States)

    Forbrich, A.; Shao, P.; Shi, W.; Zemp, Roger J.

    2016-12-01

    Photoacoustic (PA) imaging has been utilized to quantify the lifetime profile of exogenous agents using a series of pump-probe pulses with a varying time delay; however, current techniques typically lead to long acquisition times which are sensitive to motion and cause absorption or photobleaching. We introduce a technique called lifetime-weighted imaging, which uses only three laser pulses to preferentially weight signals from chromophores with long lifetimes (including exogenous contrast agents with triplet excited states such as methylene blue and porphyrins) while nulling chromophores with short picosecond- to nanosecond-scale lifetimes (including hemoglobin). This technique detects the PA signal from a probe pulse either with or without a pump pulse. By subtracting the probe-only signal from the pump-present probe signal, we effectively eliminate signals from chromophores with short lifetimes while preserving PA signals from chromophores with long-lifetimes. We demonstrate the oxygen-dependent lifetime of both methylene blue and porphyrin-lipids and demonstrate both ground-state recovery and excited-state lifetime-weighted imaging. Lifetime-weighted PA imaging may have applications in many molecular imaging application including: photodynamic therapy dosimetry guidance and oxygen sensing.

  11. Copulas Between Wealth and Lifetime

    Institute of Scientific and Technical Information of China (English)

    YE Dongyan

    2009-01-01

    The life insurance industry is very interested in how a person's lifetime is related to his wealth with financial advisors interested in how even a person's portfolio choice affects his lifetime. This paper presents a statistical analysis combined with intuitive relationships between lifetime and wealth. Key properties of this relationship are given and then various copulas are analyzed to see whether they have these properties. Other advantages and disadvantages of these copulas for describing the dependence are stated. The results show that some copulas are not appropriate for relating lifetime and wealth, including the Gaussian family.

  12. A reformulation of the Cost Plus Net Value Change (C+NVC) model of wildfire economics

    Science.gov (United States)

    Geoffrey H. Donovan; Douglas B. Rideout

    2003-01-01

    The Cost plus Net Value Change (C+NVC) model provides the theoretical foundation for wildland fire economics and provides the basis for the National Fire Management Analysis System (NFMAS). The C+NVC model is based on the earlier least Cost plus Loss model (LC+L) expressed by Sparhawk (1925). Mathematical and graphical analysis of the LC+L model illustrates two errors...

  13. Multicriteria Cost Assessment and Logistics Modeling for Military Humanitarian Assistance and Disaster Relief Aerial Delivery Operations

    Science.gov (United States)

    2015-03-01

    goal programming model , and we used Excel/ VBA to create an auto- matic, user-friendly interface with the decision maker for model input and analysis of...ARL-TR-7229•MAR 2015 US Army Research Laboratory Multicriteria Cost Assessment and Logistics Modeling for Military Humanitarian Assistance and...Cost Assessment and Logistics Modeling for Military Humanitarian Assistance and Disaster Relief Aerial Delivery Operations by Nathaniel Bastian

  14. The neutron lifetime experiment PENeLOPE

    Energy Technology Data Exchange (ETDEWEB)

    Schreyer, Wolfgang [Technische Universitaet Muenchen (Germany); Collaboration: PENeLOPE-Collaboration

    2015-07-01

    The neutron lifetime τ{sub n}=880.3±1.1 s is an important parameter in the Standard Model of particle physics and in Big Bang cosmology. Several systematic corrections of previously published results reduced the PDG world average by several σ in the last years and call for a new experiment with complementary systematics. The experiment PENeLOPE, currently under construction at the Physik-Department of Technische Universitaet Muenchen, aims to determine the neutron lifetime with a precision of 0.1 s. It will trap ultra-cold neutrons in a magneto-gravitational trap using a large superconducting magnet and will measure their lifetime by both neutron counting and online proton detection. This presentation gives an overview over the latest developments of the experiment.

  15. Cost model relationships between textile manufacturing processes and design details for transport fuselage elements

    Science.gov (United States)

    Metschan, Stephen L.; Wilden, Kurtis S.; Sharpless, Garrett C.; Andelman, Rich M.

    1993-01-01

    Textile manufacturing processes offer potential cost and weight advantages over traditional composite materials and processes for transport fuselage elements. In the current study, design cost modeling relationships between textile processes and element design details were developed. Such relationships are expected to help future aircraft designers to make timely decisions on the effect of design details and overall configurations on textile fabrication costs. The fundamental advantage of a design cost model is to insure that the element design is cost effective for the intended process. Trade studies on the effects of processing parameters also help to optimize the manufacturing steps for a particular structural element. Two methods of analyzing design detail/process cost relationships developed for the design cost model were pursued in the current study. The first makes use of existing databases and alternative cost modeling methods (e.g. detailed estimating). The second compares design cost model predictions with data collected during the fabrication of seven foot circumferential frames for ATCAS crown test panels. The process used in this case involves 2D dry braiding and resin transfer molding of curved 'J' cross section frame members having design details characteristic of the baseline ATCAS crown design.

  16. The cost of simplifying air travel when modeling disease spread.

    Directory of Open Access Journals (Sweden)

    Justin Lessler

    Full Text Available BACKGROUND: Air travel plays a key role in the spread of many pathogens. Modeling the long distance spread of infectious disease in these cases requires an air travel model. Highly detailed air transportation models can be over determined and computationally problematic. We compared the predictions of a simplified air transport model with those of a model of all routes and assessed the impact of differences on models of infectious disease. METHODOLOGY/PRINCIPAL FINDINGS: Using U.S. ticket data from 2007, we compared a simplified "pipe" model, in which individuals flow in and out of the air transport system based on the number of arrivals and departures from a given airport, to a fully saturated model where all routes are modeled individually. We also compared the pipe model to a "gravity" model where the probability of travel is scaled by physical distance; the gravity model did not differ significantly from the pipe model. The pipe model roughly approximated actual air travel, but tended to overestimate the number of trips between small airports and underestimate travel between major east and west coast airports. For most routes, the maximum number of false (or missed introductions of disease is small (<1 per day but for a few routes this rate is greatly underestimated by the pipe model. CONCLUSIONS/SIGNIFICANCE: If our interest is in large scale regional and national effects of disease, the simplified pipe model may be adequate. If we are interested in specific effects of interventions on particular air routes or the time for the disease to reach a particular location, a more complex point-to-point model will be more accurate. For many problems a hybrid model that independently models some frequently traveled routes may be the best choice. Regardless of the model used, the effect of simplifications and sensitivity to errors in parameter estimation should be analyzed.

  17. Tremendously increased lifetime of MCP-PMTs

    Science.gov (United States)

    Lehmann, A.; Britting, A.; Eyrich, W.; Pfaffinger, M.; Uhlig, F.; Belias, A.; Dzhygadlo, R.; Gerhardt, A.; Götzen, K.; Kalicy, G.; Krebs, M.; Lehmann, D.; Nerling, F.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Schwiening, J.; Traxler, M.; Zühlsdorf, M.; Düren, M.; Etzelmüller, E.; Föhl, K.; Hayrapetyan, A.; Kröck, B.; Merle, O.; Rieke, J.; Schmidt, M.; Cowie, E.; Keri, T.; Achenbach, P.; Cardinali, M.; Hoek, M.; Lauth, W.; Schlimme, S.; Sfienti, C.; Thiel, M.

    2017-02-01

    Microchannel plate (MCP) PMTs are very attractive photon sensors for low light level applications in strong magnetic fields. However, until recently the main drawback of MCP-PMTs was their aging behavior which manifests itself in a limited lifetime due to a rapidly decreasing quantum efficiency (QE) of the photo cathode (PC) as the integrated anode charge (IAC) increases. In the latest models of PHOTONIS, Hamamatsu, and BINP novel techniques are applied to avoid these aging effects which are supposed to be mainly caused by feedback ion impinging on the PC and damaging it. For more than four years we are running a long-term aging test with new lifetime-enhanced MCP-PMT models by simultaneously illuminating various PMTs with roughly the same photon rate. This allows a fair comparison of the lifetime of all investigated MCP-PMTs and will give some insight into the best techniques to be applied for a lifetime enhancement. In this paper the results of comprehensive aging tests will be discussed. Gain, dark count rate and QE were investigated for their dependence on the IAC. The QE was measured spectrally resolved and as a function of the position across the PC to identify regions where the damage develops first. For the best performing tubes the lifetime improvement compared to former MCP-PMTs is a factor of ∼ 50 based on an IAC of meanwhile > 10 C /cm2. This breakthrough in the lifetime of MCP-PMTs was achieved by coating the MCP pores with an atomic layer deposition (ALD) technique.

  18. Software Cost Estimation Model Based on Integration of Multi-agent and Case-Based Reasoning

    Directory of Open Access Journals (Sweden)

    Hasan Al-Sakran

    2006-01-01

    Full Text Available Accurate software cost estimation is a vital task that affects the firm's software investment decisions before committing required resources to that project or bidding for a contract. This study proposes an improved Case-Based Reasoning (CBR approach integrated with multi-agent technology to retrieve similar projects from multi-organizational distributed datasets. The study explores the possibility of building a software cost estimation model by collecting software cost data from distributed predefined project cost databases. The model applying CBR method to find similar projects in historical data derived from measured software projects developed by different organizations.

  19. Forecasting the Unit Cost of a Product with Some Linear Fuzzy Collaborative Forecasting Models

    Directory of Open Access Journals (Sweden)

    Toly Chen

    2012-10-01

    Full Text Available Forecasting the unit cost of every product type in a factory is an important task. However, it is not easy to deal with the uncertainty of the unit cost. Fuzzy collaborative forecasting is a very effective treatment of the uncertainty in the distributed environment. This paper presents some linear fuzzy collaborative forecasting models to predict the unit cost of a product. In these models, the experts’ forecasts differ and therefore need to be aggregated through collaboration. According to the experimental results, the effectiveness of forecasting the unit cost was considerably improved through collaboration.

  20. A Costing Analysis for Decision Making Grid Model in Failure-Based Maintenance

    Directory of Open Access Journals (Sweden)

    Burhanuddin M. A.

    2011-01-01

    Full Text Available Background. In current economic downturn, industries have to set good control on production cost, to maintain their profit margin. Maintenance department as an imperative unit in industries should attain all maintenance data, process information instantaneously, and subsequently transform it into a useful decision. Then act on the alternative to reduce production cost. Decision Making Grid model is used to identify strategies for maintenance decision. However, the model has limitation as it consider two factors only, that is, downtime and frequency of failures. We consider third factor, cost, in this study for failure-based maintenance. The objective of this paper is to introduce the formulae to estimate maintenance cost. Methods. Fish bone analysis conducted with Ishikawa model and Decision Making Grid methods are used in this study to reveal some underlying risk factors that delay failure-based maintenance. The goal of the study is to estimate the risk factor that is, repair cost to fit in the Decision Making Grid model. Decision Making grid model consider two variables, frequency of failure and downtime in the analysis. This paper introduces third variable, repair cost for Decision Making Grid model. This approaches give better result to categorize the machines, reduce cost, and boost the earning for the manufacturing plant. Results. We collected data from one of the food processing factories in Malaysia. From our empirical result, Machine C, Machine D, Machine F, and Machine I must be in the Decision Making Grid model even though their frequency of failures and downtime are less than Machine B and Machine N, based on the costing analysis. The case study and experimental results show that the cost analysis in Decision Making Grid model gives more promising strategies in failure-based maintenance. Conclusions. The improvement of Decision Making Grid model for decision analysis with costing analysis is our contribution in this paper for

  1. Inventory Model (M,T) With Quadratic Backorder Costs And Continuous Lead Time Series 1

    OpenAIRE

    Dr. Martin Osawaru Omorodion

    2014-01-01

    We have assumed in this paper that demand follows a normal distribution, and lead times follow a gamma distribution and backorder costs is quadratic. The (M, T) Model an order is made to bring it to M at review time. The model is derived from the (nQ,R,T) model which at review time an integral multiple Q is ordered. After deriving the inventory costs for (nQ, R,T) we set Q 0 to obtain the (M,T) inventory costs by making use of the differentiation of the (nQ,R,T) model. The (M,T) inventory cos...

  2. Traffic congestion and the lifetime of networks with moving nodes

    Science.gov (United States)

    Yang, Xianxia; Li, Jie; Pu, Cunlai; Yan, Meichen; Sharafat, Rajput Ramiz; Yang, Jian; Gakis, Konstantinos; Pardalos, Panos M.

    2017-01-01

    For many power-limited networks, such as wireless sensor networks and mobile ad hoc networks, maximizing the network lifetime is the first concern in the related designing and maintaining activities. We study the network lifetime from the perspective of network science. In our model, nodes are initially assigned a fixed amount of energy moving in a square area and consume the energy when delivering packets. We obtain four different traffic regimes: no, slow, fast, and absolute congestion regimes, which are basically dependent on the packet generation rate. We derive the network lifetime by considering the specific regime of the traffic flow. We find that traffic congestion inversely affects network lifetime in the sense that high traffic congestion results in short network lifetime. We also discuss the impacts of factors such as communication radius, node moving speed, routing strategy, etc., on network lifetime and traffic congestion.

  3. A model to estimate the cost effectiveness of the indoorenvironment improvements in office work

    Energy Technology Data Exchange (ETDEWEB)

    Seppanen, Olli; Fisk, William J.

    2004-06-01

    Deteriorated indoor climate is commonly related to increases in sick building syndrome symptoms, respiratory illnesses, sick leave, reduced comfort and losses in productivity. The cost of deteriorated indoor climate for the society is high. Some calculations show that the cost is higher than the heating energy costs of the same buildings. Also building-level calculations have shown that many measures taken to improve indoor air quality and climate are cost-effective when the potential monetary savings resulting from an improved indoor climate are included as benefits gained. As an initial step towards systemizing these building level calculations we have developed a conceptual model to estimate the cost-effectiveness of various measures. The model shows the links between the improvements in the indoor environment and the following potential financial benefits: reduced medical care cost, reduced sick leave, better performance of work, lower turn over of employees, and lower cost of building maintenance due to fewer complaints about indoor air quality and climate. The pathways to these potential benefits from changes in building technology and practices go via several human responses to the indoor environment such as infectious diseases, allergies and asthma, sick building syndrome symptoms, perceived air quality, and thermal environment. The model also includes the annual cost of investments, operation costs, and cost savings of improved indoor climate. The conceptual model illustrates how various factors are linked to each other. SBS symptoms are probably the most commonly assessed health responses in IEQ studies and have been linked to several characteristics of buildings and IEQ. While the available evidence indicates that SBS symptoms can affect these outcomes and suspects that such a linkage exists, at present we can not quantify the relationships sufficiently for cost-benefit modeling. New research and analyses of existing data to quantify the financial

  4. Lifetime of Mechanical Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Leland, K.

    1999-07-01

    The gas plant at Kaarstoe was built as part of the Statpipe gas transport system and went on stream in 1985. In 1993 another line was routed from the Sleipner field to carry condensate, and the plant was extended accordingly. Today heavy additional supply- and export lines are under construction, and the plant is extended more than ever. The main role of the factory is to separate the raw gas into commercial products and to pump or ship it to the markets. The site covers a large number of well-known mechanical equipment. This presentation deals with piping, mechanical and structural disciplines. The lifetime of mechanical equipment is often difficult to predict as it depends on many factors, and the subject is complex. Mechanical equipment has been kept in-house, which provides detailed knowledge of the stages from a new to a 14 years old plant. The production regularity has always been very high, as required. The standard of the equipment is well kept, support systems are efficient, and human improvisation is extremely valuable.

  5. The cost effectiveness and cost utility of valsartan in chronic heart failure therapy in Italy: a probabilistic markov model.

    Science.gov (United States)

    Pradelli, Lorenzo; Iannazzo, Sergio; Zaniolo, Orietta

    2009-01-01

    To evaluate the cost effectiveness and cost utility of the use of valsartan in addition to standard therapy for the treatment of patients with chronic heart failure with low left ventricular ejection fraction (LVEF). The study was conducted by means of a cohort simulation based on a probabilistic Markov model and projecting the 23-month follow-up results of the Val-HeFT (Valsartan Heart Failure Trial) study over a 10-year time horizon. The model included four states (New York Heart Association [NYHA] classes II, III, IV, and death), and had a cycle duration of 1 month. Probabilistic simulations were performed using the WinBUGS software for Bayesian analysis. The distribution of patient parameters (sex, age, use of beta-adrenoceptor antagonists, and ACE inhibitors) in the simulated population were derived from the Italian heart failure patient population. Individual mortality data were derived from general mortality data by multiplying by a NYHA state-specific relative risk, while the probability of changing NYHA class was taken from the Val-HeFT data. Costs (2007 values) were calculated from the perspective of the Italian Health Service (IHS) and included costs for drugs and heart failure hospitalizations. Quality-of-life (QOL) weights were obtained by using published health-related QOL data for heart failure patients. A 3.5% annual discount rate was applied. Probabilistic sensitivity analysis was performed on each parameter using original-source 95% confidence interval (CI) values, or a +/-10% range when 95% CI values were unavailable. For the 10-year time horizon, patients were estimated to live for an average of 2.3 years or 1.7 quality-adjusted life-years (QALYs), with slight increases in the valsartan group. In this group, hospitalizations for worsening heart failure were predicted to be significantly reduced and overall treatment costs per patient to decrease by about and U20AC;550. In subgroup analyses, valsartan lost dominance in patients in NYHA II, and in

  6. Artificial Intelligence for Constructing Accurate, Low-Cost Models and

    Science.gov (United States)

    2005-01-01

    0.5 1 1.5 2 2.5 -12 -7 -2 3 8 13 AOA C l Equation Model Human Predicition Machine Learning Test Data Figure C-14 NACA 4421 Model Comparison...Natrajan, Anand, and Srinivasan, Sudhir, (1997) “Consistency Maintenance in Multiresolution Simulation”, ACM Transactions on Modeling and

  7. MESSOC capabilities and results. [Model for Estimating Space Station Opertions Costs

    Science.gov (United States)

    Shishko, Robert

    1990-01-01

    MESSOC (Model for Estimating Space Station Operations Costs) is the result of a multi-year effort by NASA to understand and model the mature operations cost of Space Station Freedom. This paper focuses on MESSOC's ability to contribute to life-cycle cost analyses through its logistics equations and databases. Together, these afford MESSOC the capability to project not only annual logistics costs for a variety of Space Station scenarios, but critical non-cost logistics results such as annual Station maintenance crewhours, upweight/downweight, and on-orbit sparing availability as well. MESSOC results using current logistics databases and baseline scenario have already shown important implications for on-orbit maintenance approaches, space transportation systems, and international operations cost sharing.

  8. Lifetime Improvement by Battery Scheduling

    NARCIS (Netherlands)

    Jongerden, M.R.; Schmitt, Jens B.; Haverkort, Boudewijn R.H.M.

    2012-01-01

    The use of mobile devices is often limited by the lifetime of their batteries. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to

  9. Lifetime improvement by battery scheduling

    NARCIS (Netherlands)

    Jongerden, M.R.; Haverkort, Boudewijn R.H.M.

    2011-01-01

    The use of mobile devices is often limited by the lifetime of its battery. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to the

  10. Lifetime Improvement by Battery Scheduling

    NARCIS (Netherlands)

    Jongerden, M.R.; Schmitt, Jens B.; Haverkort, Boudewijn R.H.M.

    The use of mobile devices is often limited by the lifetime of their batteries. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to

  11. Lifetime improvement by battery scheduling

    NARCIS (Netherlands)

    Jongerden, M.R.; Haverkort, Boudewijn R.H.M.

    The use of mobile devices is often limited by the lifetime of its battery. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to the

  12. Construction Cost Estimates for Residences in Spain: practical application of the Pcr.5n model

    OpenAIRE

    Pina Ruiz, Pedro; García Erviti, Federico; Ramírez Pacheco, Gema María

    2013-01-01

    The construction cost estimation systems in Spain are undeveloped and, hence, infrequently used by technicians and professionals in the building sector. However, estimation of an approximate real cost prior to the execution of the work is compulsory under current legal regulations (Technical Building Code). Therefore, the development of research projects on construction cost estimation models such as the one described and demonstrated in this talk is extremely interesting.

  13. Handbook for cost estimating. A method for developing estimates of costs for generic actions for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ball, J.R.; Cohen, S.; Ziegler, E.Z.

    1984-10-01

    This document provides overall guidance to assist the NRC in preparing the types of cost estimates required by the Regulatory Analysis Guidelines and to assist in the assignment of priorities in resolving generic safety issues. The Handbook presents an overall cost model that allows the cost analyst to develop a chronological series of activities needed to implement a specific regulatory requirement throughout all applicable commercial LWR power plants and to identify the significant cost elements for each activity. References to available cost data are provided along with rules of thumb and cost factors to assist in evaluating each cost element. A suitable code-of-accounts data base is presented to assist in organizing and aggregating costs. Rudimentary cost analysis methods are described to allow the analyst to produce a constant-dollar, lifetime cost for the requirement. A step-by-step example cost estimate is included to demonstrate the overall use of the Handbook.

  14. Business Models for Cost Sharing and Capability Sustainment

    Science.gov (United States)

    2012-04-30

    business models need to adapt in a continuous process in most cases, notably the major platforms and technologies featured in this research. Demil and...capability or availability. The business model, as seen by Demil and Lecocq (2010), delivers dynamic consistency by ensuring that profitability and...Cambridge, UK: Cambridge University Press. Demil , B., & Lecocq, X. (2010). Business model evolution: In search of dynamic consistency. Long Range

  15. Vendor-Buyers relationship model for deteriorating items with shortages, fuzzy trapezoidal costs and inflation

    Directory of Open Access Journals (Sweden)

    Singh Chaman

    2013-01-01

    Full Text Available In this paper, an integrated inventory model is developed from the perspective of a single vendor and multi-buyers for deteriorating items under fuzzy environment and inflation. In the development of the model, it is assumed that all costs parameters, demand and the production rates are imprecise in nature; they are represented by the trapezoidal fuzzy numbers, as these parameters are not constant and can be disturbed due to daily market changes. We use function principle as arithmetic operations to find the total inventory cost in fuzzy sense and Graded Mean - Integration Representation Method to defuzzify the fuzzy total inventory cost. Inflation is used to find the present worth of total cost. Since the optimal policy of buyers may not be the most economical for a vendor, thus to deal with this situation, integrated cost policy is used to reach the optimal policy. Finally, a numerical example is given to illustrate the model.

  16. Prediction of Combine Economic Life Based on Repair and Maintenance Costs Model

    Directory of Open Access Journals (Sweden)

    A Rohani

    2014-09-01

    Full Text Available Farm machinery managers often need to make complex economic decisions on machinery replacement. Repair and maintenance costs can have significant impacts on this economic decision. The farm manager must be able to predict farm machinery repair and maintenance costs. This study aimed to identify a regression model that can adequately represent the repair and maintenance costs in terms of machine age in cumulative hours of use. The regression model has the ability to predict the repair and maintenance costs for longer time periods. Therefore, it can be used for the estimation of the economic life. The study was conducted using field data collected from 11 John-Deer 955 combine harvesters used in several western provinces of Iran. It was found that power model has a better performance for the prediction of combine repair and maintenance costs. The results showed that the optimum replacement age of John-Deer 955 combine was 54300 cumulative hours.

  17. Application of the TDABC model in the logistics process using different capacity cost rates

    Directory of Open Access Journals (Sweden)

    Paulo Afonso

    2016-12-01

    Full Text Available Purpose: The understanding of logistics process in terms of costs and profitability is a complex task and there is a need of more research and applied work on these issues. In this research project, the concepts underlying Time-Driven Activity Based Costing (TDABC have been used in the context of logistics costs. Design/methodology/approach: A Distribution Centre of wood and carpentry related materials has been studied. A multidisciplinary team has been composed to support the project including the researchers and three employees of the company responsible for accounting, logistics and warehousing. The design and implementation of the costing model asked for a deep understanding of the different tasks and processes that should be considered. Accordingly, a TDABC model for the logistics function was developed. Findings: The cost model presented here is supported on a series of time equations designed for the logistics function which allow the analysis and discussion of costs and profitability of different cost objects namely, products, clients, distribution channels, processes and activities. The cost of unused capacity and the effectiveness of logistics processes are also highlighted in this model. Research limitations/implications: In a case study, results and implications cannot be directly or immediately generalized. Nevertheless, the proposed time equations and cost model can be easily adapted to explain other types of logistics functions and it gives the foundations or other TDABC models with more than one capacity cost rate. Practical implications: The TDABC model developed in this case study can be used in similar cases and as a basis for the analysis of logistics costs in other logistics processes. Furthermore, managers can rely on the proposed approach to analyze products’ profitability and logistics cost structure.  Originality/value: In this case, different capacity cost rates were computed in order to reflect appropriately the

  18. Development and validation of chemistry agnostic flow battery cost performance model and application to nonaqueous electrolyte systems: Chemistry agnostic flow battery cost performance model

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Alasdair [Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, P.O. Box 999 Richland WA 99352 USA; Thomsen, Edwin [Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, P.O. Box 999 Richland WA 99352 USA; Reed, David [Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, P.O. Box 999 Richland WA 99352 USA; Stephenson, David [Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, P.O. Box 999 Richland WA 99352 USA; Sprenkle, Vincent [Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, P.O. Box 999 Richland WA 99352 USA; Liu, Jun [Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, P.O. Box 999 Richland WA 99352 USA; Viswanathan, Vilayanur [Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, P.O. Box 999 Richland WA 99352 USA

    2016-01-01

    A chemistry agnostic cost performance model is described for a nonaqueous flow battery. The model predicts flow battery performance by estimating the active reaction zone thickness at each electrode as a function of current density, state of charge, and flow rate using measured data for electrode kinetics, electrolyte conductivity, and electrode-specific surface area. Validation of the model is conducted using a 4kW stack data at various current densities and flow rates. This model is used to estimate the performance of a nonaqueous flow battery with electrode and electrolyte properties used from the literature. The optimized cost for this system is estimated for various power and energy levels using component costs provided by vendors. The model allows optimization of design parameters such as electrode thickness, area, flow path design, and operating parameters such as power density, flow rate, and operating SOC range for various application duty cycles. A parametric analysis is done to identify components and electrode/electrolyte properties with the highest impact on system cost for various application durations. A pathway to 100$kWh-1 for the storage system is identified.

  19. A Flexible Logistics Distribution Hub Model considering Cost Weighted Time

    Directory of Open Access Journals (Sweden)

    Wenxue Ran

    2017-01-01

    Full Text Available The delivery time of order has become an important fact for customers to evaluate logistics services. Due to the diverse and large quantities of orders in the background of electronic commerce, how to improve the flexibility of distribution hub and reduce the waiting time of customers becomes one of the most challenging questions for logistics companies. With this in mind, this paper proposes a new method of flexibility assessment in distribution hub by introducing cost weighted time (CWT. The advantages of supply hub operation mode in delivery flexibility are verified by the approach: the mode has pooling effects and uniform distribution characteristics; these traits can reduce overlapping delivery time to improve the flexibility in the case of two suppliers. Numerical examples show that the supply hub operation mode is more flexible than decentralized distribution operation mode in multidelivery cycles.

  20. Some Useful Cost-Benefit Criteria for Evaluating Computer-Based Test Delivery Models and Systems

    Science.gov (United States)

    Luecht, Richard M.

    2005-01-01

    Computer-based testing (CBT) is typically implemented using one of three general test delivery models: (1) multiple fixed testing (MFT); (2) computer-adaptive testing (CAT); or (3) multistage testing (MSTs). This article reviews some of the real cost drivers associated with CBT implementation--focusing on item production costs, the costs…