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Sample records for cost-effective digital control

  1. A Cost-Effective Model for Digital Forensic Investigations

    NASA Astrophysics Data System (ADS)

    Overill, Richard; Kwan, Michael; Chow, Kam-Pui; Lai, Pierre; Law, Frank

    Because of the way computers operate, every discrete event potentially leaves a digital trace. These digital traces must be retrieved during a digital forensic investigation to prove or refute an alleged crime. Given resource constraints, it is not always feasible (or necessary) for law enforcement to retrieve all the related digital traces and to conduct comprehensive investigations. This paper attempts to address the issue by proposing a model for conducting swift, practical and cost-effective digital forensic investigations.

  2. Emission control cost-effectiveness of alternative-fuel vehicles

    SciTech Connect

    Wang, Q.; Sperling, D.; Olmstead, J.

    1993-06-14

    Although various legislation and regulations have been adopted to promote the use of alternative-fuel vehicles for curbing urban air pollution problems, there is a lack of systematic comparisons of emission control cost-effectiveness among various alternative-fuel vehicle types. In this paper, life-cycle emission reductions and life-cycle costs were estimated for passenger cars fueled with methanol, ethanol, liquefied petroleum gas, compressed natural gas, and electricity. Vehicle emission estimates included both exhaust and evaporative emissions for air pollutants of hydrocarbon, carbon monoxide, nitrogen oxides, and air-toxic pollutants of benzene, formaldehyde, 1,3-butadiene, and acetaldehyde. Vehicle life-cycle cost estimates accounted for vehicle purchase prices, vehicle life, fuel costs, and vehicle maintenance costs. Emission control cost-effectiveness presented in dollars per ton of emission reduction was calculated for each alternative-fuel vehicle types from the estimated vehicle life-cycle emission reductions and costs. Among various alternative-fuel vehicle types, compressed natural gas vehicles are the most cost-effective vehicle type in controlling vehicle emissions. Dedicated methanol vehicles are the next most cost-effective vehicle type. The cost-effectiveness of electric vehicles depends on improvements in electric vehicle battery technology. With low-cost, high-performance batteries, electric vehicles are more cost-effective than methanol, ethanol, and liquified petroleum gas vehicles.

  3. Cost-effectiveness analysis of optimal control measures for tuberculosis.

    PubMed

    Rodrigues, Paula; Silva, Cristiana J; Torres, Delfim F M

    2014-10-01

    We propose and analyze an optimal control problem where the control system is a mathematical model for tuberculosis that considers reinfection. The control functions represent the fraction of early latent and persistent latent individuals that are treated. Our aim was to study how these control measures should be implemented, for a certain time period, in order to reduce the number of active infected individuals, while minimizing the interventions implementation costs. The optimal intervention is compared along different epidemiological scenarios, by varying the transmission coefficient. The impact of variation of the risk of reinfection, as a result of acquired immunity to a previous infection for treated individuals on the optimal controls and associated solutions, is analyzed. A cost-effectiveness analysis is done, to compare the application of each one of the control measures, separately or in combination. PMID:25245395

  4. Cost-Effectiveness of Automated Digital Microscopy for Diagnosis of Active Tuberculosis

    PubMed Central

    Jha, Swati; Ismail, Nazir; Clark, David; Lewis, James J.; Omar, Shaheed; Dreyer, Andries; Chihota, Violet; Churchyard, Gavin; Dowdy, David W.

    2016-01-01

    Background Automated digital microscopy has the potential to improve the diagnosis of tuberculosis (TB), particularly in settings where molecular testing is too expensive to perform routinely. The cost-effectiveness of TB diagnostic algorithms using automated digital microscopy remains uncertain. Methods Using data from a demonstration study of an automated digital microscopy system (TBDx, Applied Visual Systems, Inc.), we performed an economic evaluation of TB diagnosis in South Africa from the health system perspective. The primary outcome was the incremental cost per new TB diagnosis made. We considered costs and effectiveness of different algorithms for automated digital microscopy, including as a stand-alone test and with confirmation of positive results with Xpert MTB/RIF (‘Xpert’, Cepheid, Inc.). Results were compared against both manual microscopy and universal Xpert testing. Results In settings willing to pay $2000 per incremental TB diagnosis, universal Xpert was the preferred strategy. However, where resources were not sufficient to support universal Xpert, and a testing volume of at least 30 specimens per day could be ensured, automated digital microscopy with Xpert confirmation of low-positive results could facilitate the diagnosis of 79–84% of all Xpert-positive TB cases, at 50–60% of the total cost. The cost-effectiveness of this strategy was $1280 per incremental TB diagnosis (95% uncertainty range, UR: $340-$3440) in the base case, but improved under conditions likely reflective of many settings in sub-Saharan Africa: $677 per diagnosis (95% UR: $450-$935) when sensitivity of manual smear microscopy was lowered to 0.5, and $956 per diagnosis (95% UR: $40-$2910) when the prevalence of multidrug-resistant TB was lowered to 1%. Conclusions Although universal Xpert testing is the preferred algorithm for TB diagnosis when resources are sufficient, automated digital microscopy can identify the majority of cases and halve the cost of diagnosis and

  5. Controlling Reactive Nitrogen: Attaining Cost Effectiveness and Institutional Alignment

    NASA Astrophysics Data System (ADS)

    Doering, O.

    2012-12-01

    The fact that reactive nitrogen (Nr) cascades by changing form and moving between air, land and water makes its management and control especially difficult. The cascade means that excess Nr's negative impacts may initially occur, flow through, or linger in air, land or water. The critical question becomes where and how to interdict, not only in terms of technical capacity but also in terms of cost effectiveness and institutional capacity. The nature of Nr also needs to inform the questions that need to be asked to be able to deal with Nr. For much of the world, agriculture is the major contributor to Nr.The stark trade-off often involves excess Nr that is the product of increased food production. As it is often the largest source of excess Nr, agriculture has to be a focus for Nr control and management efforts. This paper will start with the Nr balance sheet for the US and outline some of the trade-offs and opportunities for controlling Nr.The institutional responsibility and capacity to take effective action will be assessed on the basis of US institutions and their history. This will involve illustrating some of the difficulties posed by the cascading nature of Nr as it movesfrom one regulatory jurisdiction to another. Within the US agricultural sector. the history and politics of dealing with such problems will be traced as they relate to the willingness and capacity of the sector to more effectively control or manage problems like Nr. The institutional history of the sector has a strong influence onwhat can be accomplished in a cost effective way - one that is very different from the history and practice in Australia or Europe. The EPA Science Advisory Boards' suggestion that a twenty five percent reduction in excess Nr should be achievable will be traced through for agriculture and allied situations illustrating some of the possibilities and dilemmas. Finally, the issue of metrics will be addressed. As a caution to policy makers, one can obtain very different

  6. Rotavirus vaccine: a cost effective control measure for India.

    PubMed

    Kumar, Arun; Goel, Manish K; Jain, Ram Bilas; Khanna, Pardeep; Vibha, Vibha

    2012-04-01

    Globally, rotavirus diarrhea results in 453,000 deaths in children younger than 5 y—37% of deaths attributable to diarrhea and 5% of all deaths in children younger than 5 y. India alone accounts for 22% (~100,000 deaths) of all deaths attributable to rotavirus infection. Two oral rotavirus vaccines are available: Rotarix, a monovalent P1A[8] G1 vaccine (GlaxoSmithKline), and RotaTeq, a pentavalent bovine-human reassortant vaccine (Merck). Rotarix is administered in a 2-dose schedule with the first and second doses of DTP (DTP1, DTP2). RotaTeq requires a 3-dose schedule with DTP1, DTP2 and DTP3 with an interval of 4–10 weeks between doses. The first dose of either vaccine should be administered to infants aged 6–15 weeks irrespective of the history of previous rotavirus infection, and the maximum age for administering the last dose of either vaccine should be 32 weeks. Although India would require funding from international health organizations/GAVI until new indigenous rotavirus vaccine candidates are developed at a cheaper price, introduction of vaccination into the national immunization program would be a cost-effective step toward control of the rotavirus diarrhea-related morbidity and mortality in India. PMID:23071989

  7. Cost-effectiveness of digital mammography screening before the age of 50 in The Netherlands.

    PubMed

    Sankatsing, Valérie D V; Heijnsdijk, Eveline A M; van Luijt, Paula A; van Ravesteyn, Nicolien T; Fracheboud, Jacques; de Koning, Harry J

    2015-10-15

    In the Netherlands, routine mammography screening starts at age 50. This starting age may have to be reconsidered because of the increasing breast cancer incidence among women aged 40 to 49 and the recent implementation of digital mammography. We assessed the cost-effectiveness of digital mammography screening that starts between age 40 and 49, using a microsimulation model. Women were screened before age 50, in addition to the current programme (biennial 50-74). Screening strategies varied in starting age (between 40 and 50) and frequency (annual or biennial). The numbers of breast cancers diagnosed, life-years gained (LYG) and breast cancer deaths averted were predicted and incremental cost-effectiveness ratios (ICERs) were calculated to compare screening scenarios. Biennial screening from age 50 to 74 (current strategy) was estimated to gain 157 life years per 1,000 women with lifelong follow-up, compared to a situation without screening, and cost €3,376/LYG (3.5% discounted). Additional screening increased the number of LYG, compared to no screening, ranging from 168 to 242. The costs to generate one additional LYG (i.e., ICER), comparing a screening strategy to the less intensive alternative, were estimated at €5,329 (biennial 48-74 vs. current strategy), €7,628 (biennial 45-74 vs. biennial 48-74), €10,826 (biennial 40-74 vs. biennial 45-74) and €18,759 (annual 40-49 + biennial 50-74 vs. biennial 40-74). Other strategies (49 + biennial 50-74 and annual 45-49 + biennial 50-74) resulted in less favourable ICERs. These findings show that extending the Dutch screening programme by screening between age 40 and 49 is cost-effective, particularly for biennial strategies. PMID:25895135

  8. Mobile source emission control cost-effectiveness: Issues, uncertainties, and results

    SciTech Connect

    Wang, M.Q.

    1994-12-01

    Emissions from mobile sources undoubtedly contribute to US urban air pollution problems. Consequently, mobile source control measures, ranging from vehicle emission standards to reducing vehicle travel, have been adopted or proposed to help attain air quality standards. To rank various mobile source control measures, various government agencies and private organizations calculate cost-effectiveness in dollars per ton of emissions reduced. Arguments for or against certain control measures are often made on the basis of the calculated cost-effectiveness. Yet, different studies may yield significantly different cost-effectiveness results, because of the various methodologies used and assumptions regarding the values of costs and emission reductions. Because of the methodological differences, the cost-effectiveness results may not be comparable between studies. Use of incomparable cost-effectiveness results may result in adoption of ineffective control measures. This paper first discusses some important methodological issues involved in cost-effectiveness calculation for mobile sources and proposes appropriate, systematic methods for dealing with these issues. Various studies have been completed recently to evaluate the cost-effectiveness of mobile source emission control measures. These studies resulted in wide variations in the cost-effectiveness for same control measures. Methodological assumptions used in each study are presented and, based on the proposed methods for cost-effectiveness calculation, adjustments are applied to the original estimates in each study to correct inappropriate methodological assumptions and to make the studies comparable. Finally, mobile source control measures are ranked on the basis of the adjusted cost-effectiveness estimates.

  9. A high performance cost-effective digital complex correlator for an X-band polarimetry survey.

    PubMed

    Bergano, Miguel; Rocha, Armando; Cupido, Luís; Barbosa, Domingos; Villela, Thyrso; Boas, José Vilas; Rocha, Graça; Smoot, George F

    2016-01-01

    The detailed knowledge of the Milky Way radio emission is important to characterize galactic foregrounds masking extragalactic and cosmological signals. The update of the global sky models describing radio emissions over a very large spectral band requires high sensitivity experiments capable of observing large sky areas with long integration times. Here, we present the design of a new 10 GHz (X-band) polarimeter digital back-end to map the polarization components of the galactic synchrotron radiation field of the Northern Hemisphere sky. The design follows the digital processing trends in radio astronomy and implements a large bandwidth (1 GHz) digital complex cross-correlator to extract the Stokes parameters of the incoming synchrotron radiation field. The hardware constraints cover the implemented VLSI hardware description language code and the preliminary results. The implementation is based on the simultaneous digitized acquisition of the Cartesian components of the two linear receiver polarization channels. The design strategy involves a double data rate acquisition of the ADC interleaved parallel bus, and field programmable gate array device programming at the register transfer mode. The digital core of the back-end is capable of processing 32 Gbps and is built around an Altera field programmable gate array clocked at 250 MHz, 1 GSps analog to digital converters and a clock generator. The control of the field programmable gate array internal signal delays and a convenient use of its phase locked loops provide the timing requirements to achieve the target bandwidths and sensitivity. This solution is convenient for radio astronomy experiments requiring large bandwidth, high functionality, high volume availability and low cost. Of particular interest, this correlator was developed for the Galactic Emission Mapping project and is suitable for large sky area polarization continuum surveys. The solutions may also be adapted to be used at signal processing

  10. Cost-Effectiveness of Aflatoxin Control Methods: Economic Incentives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiple sectors in U.S. crop industries – growers, elevators, handlers/shellers, processors, distributors, and consumers – are affected by aflatoxin contamination of commodities, and have the potential to control it. Aflatoxin control methods at both preharvest and postharvest levels have been dev...

  11. Is glycemic control of the critically ill cost-effective?

    PubMed

    Krinsley, James S

    2014-10-01

    Intensive monitoring of blood glucose levels and treatment of hyperglycemia have been associated with significant improvements in morbidity and mortality in the critically ill. In contrast to the large prospective and observational body of data relating glycemic control and clinical outcomes, the financial impact of glycemic control implementation has not been as well described. This article details data from interventional trials of intensive insulin therapy; investigations that relate dysglycemia to morbidity, particularly intensive care unit (ICU)-acquired infections and increased ICU length of stay; and evaluations of the attributable cost of nosocomial infection in order to construct a sensitivity analysis of the net economic impact of glycemic control. It concludes that glycemic control is associated with positive financial outcomes, even using very conservative assumptions, and provides the reader with an automated spreadsheet to estimate the financial implications of glycemic control using assumptions based on locally derived data. PMID:25502129

  12. Burner modifications for cost effective NO{sub x} control

    SciTech Connect

    Melick, T.A.; Payne, R.; Kersch, J.

    1999-11-01

    Low NO{sub x} Burners achieve their NO{sub x} reduction principally by control of the rate of fuel/air mixing. Based on many years of low NO{sub x} burner development experience for wall fired applications, Energy and Environmental Research Corporation (EER) has found that low NO{sub x} fuel/air mixing conditions can be incorporated into conventional burners by modifying the burners as an alternative to complete burner replacement. The NO{sub x} control achieved with such Low NO{sub x} Burner Modifications is, in many cases, comparable to that of new burners but the cost to the utility is much lower. This paper presents an update on EER`s experience in applying Low NO{sub x} Burner Modifications to circular burners focusing on Delmarva Power and Light`s (Connectiv) Indian River Station.

  13. Modular motion control produces cost-effective conveying

    SciTech Connect

    Yackel, R.A.

    1997-08-01

    Collectively, US power plants move as much as 800 million tons of coal a year through the mining, transport, off-loading, stockpiling and consumption sequence, most typically through the use of belt conveyors. Plant operators oversee a process that moves mountains of coal accurately and dependably, guarding against overloading, loss of conveyor-to-conveyor synchronization, belt slippage and other malfunctions. A coal-conveying motion-control system should consist of modular, turnkey motion-sensing components that can be assembled and interconnected for any application without custom engineering. Such a system can be fail-safe, provide uninterrupted protection, resist difficult environmental conditions, integrate complex multiple functions and allow power plant operators to take instant action to protect against damage in the event of a system fault.

  14. Cost-effectiveness of interventions to control Campylobacter in the New Zealand poultry meat food supply.

    PubMed

    Lake, Robin J; Horn, Beverley J; Dunn, Alex H; Parris, Ruth; Green, F Terri; McNickle, Don C

    2013-07-01

    An analysis of the cost-effectiveness of interventions to control Campylobacter in the New Zealand poultry supply examined a series of interventions. Effectiveness was evaluated in terms of reduced health burden measured by disability-adjusted life years (DALYs). Costs of implementation were estimated from the value of cost elements, determined by discussions with industry. Benefits were estimated by changing the inputs to a poultry food chain quantitative risk model. Proportional reductions in the number of predicted Campylobacter infections were converted into reductions in the burden of disease measured in DALYs. Cost-effectiveness ratios were calculated for each intervention, as cost per DALY reduction and the ratios compared. The results suggest that the most cost-effective interventions (lowest ratios) are at the primary processing stage. Potential phage-based controls in broiler houses were also highly cost-effective. This study is limited by the ability to quantify costs of implementation and assumptions required to estimate health benefits, but it supports the implementation of interventions at the primary processing stage as providing the greatest quantum of benefit and lowest cost-effectiveness ratios. PMID:23834790

  15. Precision digital control systems

    NASA Astrophysics Data System (ADS)

    Vyskub, V. G.; Rozov, B. S.; Savelev, V. I.

    This book is concerned with the characteristics of digital control systems of great accuracy. A classification of such systems is considered along with aspects of stabilization, programmable control applications, digital tracking systems and servomechanisms, and precision systems for the control of a scanning laser beam. Other topics explored are related to systems of proportional control, linear devices and methods for increasing precision, approaches for further decreasing the response time in the case of high-speed operation, possibilities for the implementation of a logical control law, and methods for the study of precision digital control systems. A description is presented of precision automatic control systems which make use of electronic computers, taking into account the existing possibilities for an employment of computers in automatic control systems, approaches and studies required for including a computer in such control systems, and an analysis of the structure of automatic control systems with computers. Attention is also given to functional blocks in the considered systems.

  16. Digital automatic gain control

    NASA Technical Reports Server (NTRS)

    Uzdy, Z.

    1980-01-01

    Performance analysis, used to evaluated fitness of several circuits to digital automatic gain control (AGC), indicates that digital integrator employing coherent amplitude detector (CAD) is best device suited for application. Circuit reduces gain error to half that of conventional analog AGC while making it possible to automatically modify response of receiver to match incoming signal conditions.

  17. A Cost-Effective Atomic Force Microscope for Undergraduate Control Laboratories

    ERIC Educational Resources Information Center

    Jones, C. N.; Goncalves, J.

    2010-01-01

    This paper presents a simple, cost-effective and robust atomic force microscope (AFM), which has been purposely designed and built for use as a teaching aid in undergraduate controls labs. The guiding design principle is to have all components be open and visible to the students, so the inner functioning of the microscope has been made clear to…

  18. Cost-Effective Control of Infectious Disease Outbreaks Accounting for Societal Reaction

    PubMed Central

    Fast, Shannon M.; González, Marta C.; Markuzon, Natasha

    2015-01-01

    Background Studies of cost-effective disease prevention have typically focused on the tradeoff between the cost of disease transmission and the cost of applying control measures. We present a novel approach that also accounts for the cost of social disruptions resulting from the spread of disease. These disruptions, which we call social response, can include heightened anxiety, strain on healthcare infrastructure, economic losses, or violence. Methodology The spread of disease and social response are simulated under several different intervention strategies. The modeled social response depends upon the perceived risk of the disease, the extent of disease spread, and the media involvement. Using Monte Carlo simulation, we estimate the total number of infections and total social response for each strategy. We then identify the strategy that minimizes the expected total cost of the disease, which includes the cost of the disease itself, the cost of control measures, and the cost of social response. Conclusions The model-based simulations suggest that the least-cost disease control strategy depends upon the perceived risk of the disease, as well as media intervention. The most cost-effective solution for diseases with low perceived risk was to implement moderate control measures. For diseases with higher perceived severity, such as SARS or Ebola, the most cost-effective strategy shifted toward intervening earlier in the outbreak, with greater resources. When intervention elicited increased media involvement, it remained important to control high severity diseases quickly. For moderate severity diseases, however, it became most cost-effective to implement no intervention and allow the disease to run its course. Our simulation results imply that, when diseases are perceived as severe, the costs of social response have a significant influence on selecting the most cost-effective strategy. PMID:26288274

  19. Cost-effectiveness of influenza control measures: a dynamic transmission model-based analysis.

    PubMed

    Chen, S-C; Liao, C-M

    2013-12-01

    We investigated the cost-effectiveness of different influenza control strategies in a school setting in Taiwan. A susceptible-exposure-infected-recovery (SEIR) model was used to simulate influenza transmission and we used a basic reproduction number (R 0)-asymptomatic proportion (θ) control scheme to develop a cost-effectiveness model. Based on our dynamic transmission model and economic evaluation, this study indicated that the optimal cost-effective strategy for all modelling scenarios was a combination of natural ventilation and respiratory masking. The estimated costs were US$10/year per person in winter for one kindergarten student. The cost for hand washing was estimated to be US$32/year per person, which was much lower than that of isolation (US$55/year per person) and vaccination (US$86/year per person) in containing seasonal influenza. Transmission model-based, cost-effectiveness analysis can be a useful tool for providing insight into the impacts of economic factors and health benefits on certain strategies for controlling seasonal influenza. PMID:23481024

  20. Digital wireless control system

    NASA Astrophysics Data System (ADS)

    Smith, R.

    1993-08-01

    The Digital Wireless Control System (DWCS) is designed to initiate high explosives safely while using a wireless remote control system. Numerous safety features have been designed into the fire control system to mitigate the hazards associated with remote initiation of high explosives. These safety features range from a telemetry (TM) fire control status system to mechanical timers and keyed power lockout switches. The environment, safety, and health (ES&H) Standard Operating Procedure (SOP) SP471970 is intended as a guide when working with the DWCS. This report describes the Digital Wireless Control System and outlines each component's theory of operation and its relationship to the system.

  1. Cost-effectiveness of Occupational Therapy in Older People: Systematic Review of Randomized Controlled Trials.

    PubMed

    Nagayama, Hirofumi; Tomori, Kounosuke; Ohno, Kanta; Takahashi, Kayoko; Yamauchi, Keita

    2016-06-01

    A systematic review of the cost-effectiveness of occupational therapy for older people was conducted. MEDLINE, CINAHL, Web of Science, PsycINFO, Cochrane Library, OT seeker and unpublished trials registers were searched. Reference lists of all potentially eligible studies were searched with no language restrictions. We included trial-based full economic evaluations that considered both costs and outcomes in occupational therapy for older people compared with standard care (i.e. other therapy) or no intervention. We reviewed each trial for methodological quality using the Cochrane risk of bias tool and assessed the quality of economic evaluations using a Drummond checklist. In the results of this review, we included five eligible studies (1-5) that were randomized controlled trials with high-quality economic evaluation. Two studies were full economic evaluations of interventions for fall prevention (1 and 2); two studies were full economic evaluations of preventive occupational therapy interventions (3 and 4; one was a comparison of an occupational therapy group with a social work group); one study was a full economic evaluation of occupational therapy for individuals with dementia (5). Two of the studies (one was preventive occupational therapy [3] and the other was occupational therapy for dementia [5]) found a significant effect and confirmed the cost-effectiveness of occupational therapy for older people compared with the control group. These studies found that occupational therapy for older people was clinically effective and cost-effective in comparison with standard care or other therapies. With reference to their clinical implication, these intervention studies (using a client-centred approach) suggested potentially cost-effective means to motivate clients to maintain their own health. However, this review has limitations because of the high heterogeneity of the reviewed studies on full economic evaluations of occupational therapy for older people. Future

  2. Cost-Effectiveness of Interventions to Prevent and Control Diabetes Mellitus: A Systematic Review

    PubMed Central

    Li, Rui; Zhang, Ping; Barker, Lawrence E.; Chowdhury, Farah M.; Zhang, Xuanping

    2010-01-01

    OBJECTIVE To synthesize the cost-effectiveness (CE) of interventions to prevent and control diabetes, its complications, and comorbidities. RESEARCH DESIGN AND METHODS We conducted a systematic review of literature on the CE of diabetes interventions recommended by the American Diabetes Association (ADA) and published between January 1985 and May 2008. We categorized the strength of evidence about the CE of an intervention as strong, supportive, or uncertain. CEs were classified as cost saving (more health benefit at a lower cost), very cost-effective (≤$25,000 per life year gained [LYG] or quality-adjusted life year [QALY]), cost-effective ($25,001 to $50,000 per LYG or QALY), marginally cost-effective ($50,001 to $100,000 per LYG or QALY), or not cost-effective (>$100,000 per LYG or QALY). The CE classification of an intervention was reported separately by country setting (U.S. or other developed countries) if CE varied by where the intervention was implemented. Costs were measured in 2007 U.S. dollars. RESULTS Fifty-six studies from 20 countries met the inclusion criteria. A large majority of the ADA recommended interventions are cost-effective. We found strong evidence to classify the following interventions as cost saving or very cost-effective: (I) Cost saving— 1) ACE inhibitor (ACEI) therapy for intensive hypertension control compared with standard hypertension control; 2) ACEI or angiotensin receptor blocker (ARB) therapy to prevent end-stage renal disease (ESRD) compared with no ACEI or ARB treatment; 3) early irbesartan therapy (at the microalbuminuria stage) to prevent ESRD compared with later treatment (at the macroalbuminuria stage); 4) comprehensive foot care to prevent ulcers compared with usual care; 5) multi-component interventions for diabetic risk factor control and early detection of complications compared with conventional insulin therapy for persons with type 1 diabetes; and 6) multi-component interventions for diabetic risk factor control

  3. Evaluating the cost effectiveness of national program for control of blindness in Jorhat district, India

    PubMed Central

    Laskar, Nasrin B.

    2015-01-01

    Background: We evaluated the cost of different components of the national program for control of blindness (NPCB) and assess the cost effectiveness of this program. Materials and Methods: An observational study was conducted in Jorhat District of Assam, India from July 2009 to June 2010 for assessing the cost effectiveness of the NPCB. Four broad categories of cost inputs, that is, capital costs, recurrent costs, prime/variable costs, and fixed costs were considered. The cost incurred by the provider was taken as the actual cost of delivery of different component of services to the patients, which was calculated from the costs of labor, material, and capital costs using the time utilization pattern recommended by WHO. Result: The District Blindness Control Society, Jorhat had spent 58.93% of total expense on fixed heads of which 65.86% had been spent for cataract surgery. The medical care cost was found to be Indian rupee (INR) 425 for intracapsular cataract extraction (ICCE), INR 675 for extracapsular cataract extraction + intraocular lens (ECCE + IOL) and INR 225 for refractive error correction. The patient-wise provider cost was estimated to be INR 519 for ICCE, INR 769 for ECCE + IOL implantation and INR 319 for spectacle correction of refractive error. Conclusion: National program for control of blindness is a cost effective means of controlling and treating blindness. PMID:26283841

  4. Cost-Effectiveness Analysis of Breast Cancer Control Interventions in Peru

    PubMed Central

    Zelle, Sten G.; Vidaurre, Tatiana; Abugattas, Julio E.; Manrique, Javier E.; Sarria, Gustavo; Jeronimo, José; Seinfeld, Janice N.; Lauer, Jeremy A.; Sepulveda, Cecilia R.; Venegas, Diego; Baltussen, Rob

    2013-01-01

    Objectives In Peru, a country with constrained health resources, breast cancer control is characterized by late stage treatment and poor survival. To support breast cancer control in Peru, this study aims to determine the cost-effectiveness of different breast cancer control interventions relevant for the Peruvian context. Methods We performed a cost-effectiveness analysis (CEA) according to WHO-CHOICE guidelines, from a healthcare perspective. Different screening, early detection, palliative, and treatment interventions were evaluated using mathematical modeling. Effectiveness estimates were based on observational studies, modeling, and on information from Instituto Nacional de Enfermedades Neoplásicas (INEN). Resource utilizations and unit costs were based on estimates from INEN and observational studies. Cost-effectiveness estimates are in 2012 United States dollars (US$) per disability adjusted life year (DALY) averted. Results The current breast cancer program in Peru ($8,426 per DALY averted) could be improved through implementing triennial or biennial screening strategies. These strategies seem the most cost-effective in Peru, particularly when mobile mammography is applied (from $4,125 per DALY averted), or when both CBE screening and mammography screening are combined (from $4,239 per DALY averted). Triennially, these interventions costs between $63 million and $72 million per year. Late stage treatment, trastuzumab therapy and annual screening strategies are the least cost-effective. Conclusions Our analysis suggests that breast cancer control in Peru should be oriented towards early detection through combining fixed and mobile mammography screening (age 45-69) triennially. However, a phased introduction of triennial CBE screening (age 40-69) with upfront FNA in non-urban settings, and both CBE (age 40-49) and fixed mammography screening (age 50-69) in urban settings, seems a more feasible option and is also cost-effective. The implementation of this

  5. Costs and cost-effectiveness of malaria control interventions - a systematic review

    PubMed Central

    2011-01-01

    Background The control and elimination of malaria requires expanded coverage of and access to effective malaria control interventions such as insecticide-treated nets (ITNs), indoor residual spraying (IRS), intermittent preventive treatment (IPT), diagnostic testing and appropriate treatment. Decisions on how to scale up the coverage of these interventions need to be based on evidence of programme effectiveness, equity and cost-effectiveness. Methods A systematic review of the published literature on the costs and cost-effectiveness of malaria interventions was undertaken. All costs and cost-effectiveness ratios were inflated to 2009 USD to allow comparison of the costs and benefits of several different interventions through various delivery channels, across different geographical regions and from varying costing perspectives. Results Fifty-five studies of the costs and forty three studies of the cost-effectiveness of malaria interventions were identified, 78% of which were undertaken in sub-Saharan Africa, 18% in Asia and 4% in South America. The median financial cost of protecting one person for one year was $2.20 (range $0.88-$9.54) for ITNs, $6.70 (range $2.22-$12.85) for IRS, $0.60 (range $0.48-$1.08) for IPT in infants, $4.03 (range $1.25-$11.80) for IPT in children, and $2.06 (range $0.47-$3.36) for IPT in pregnant women. The median financial cost of diagnosing a case of malaria was $4.32 (range $0.34-$9.34). The median financial cost of treating an episode of uncomplicated malaria was $5.84 (range $2.36-$23.65) and the median financial cost of treating an episode of severe malaria was $30.26 (range $15.64-$137.87). Economies of scale were observed in the implementation of ITNs, IRS and IPT, with lower unit costs reported in studies with larger numbers of beneficiaries. From a provider perspective, the median incremental cost effectiveness ratio per disability adjusted life year averted was $27 (range $8.15-$110) for ITNs, $143 (range $135-$150) for IRS, and

  6. Programmable Digital Controller

    NASA Technical Reports Server (NTRS)

    Wassick, Gregory J.

    2012-01-01

    An existing three-channel analog servo loop controller has been redesigned for piezoelectric-transducer-based (PZT-based) etalon control applications to a digital servo loop controller. This change offers several improvements over the previous analog controller, including software control over proportional-integral-derivative (PID) parameters, inclusion of other data of interest such as temperature and pressure in the control laws, improved ability to compensate for PZT hysteresis and mechanical mount fluctuations, ability to provide pre-programmed scanning and stepping routines, improved user interface, expanded data acquisition, and reduced size, weight, and power.

  7. Cost and cost-effectiveness of PPM-DOTS for tuberculosis control: evidence from India.

    PubMed Central

    Floyd, Katherine; Arora, V. K.; Murthy, K. J. R.; Lonnroth, Knut; Singla, Neeta; Akbar, Y.; Zignol, Matteo; Uplekar, Mukund

    2006-01-01

    OBJECTIVE: To assess the cost and cost-effectiveness of the Public-Private Mix DOTS (PPM-DOTS) strategy for tuberculosis (TB) control in India. METHODS: We collected data on the costs and effects of pilot PPM-DOTS projects in Delhi and Hyderabad using documentary data and interviews. The cost of PPM-DOTS was compared with public sector DOTS (i.e. DOTS delivered through public sector facilities only) and non-DOTS treatment in the private sector. Costs for 2002 in US$ were assessed for the public sector, private practitioners, and patients/attendants. Effectiveness was measured as the number of cases successfully treated. FINDINGS: The average cost per patient treated was US$ 111-123 for PPM-DOTS and public sector DOTS, and US$ 111-172 for non-DOTS treatment in the private sector. From the public sector's perspective, the cost per patient treated was lower in PPM-DOTS projects than in public sector DOTS programmes (US$ 24-33 versus US$ 63). DOTS implementation in either the public or private sectors improved treatment outcomes and substantially lowered costs incurred by patients and their attendants, compared to non-DOTS treatment in the private sector (US$ 50-60 for DOTS compared to over US$ 100 for non-DOTS). The average cost-effectiveness of PPM-DOTS and public sector DOTS was similar, at US$ 120-140 per patient successfully treated, compared to US$ 218-338 for non-DOTS private sector treatment. Incremental cost-effectiveness analysis showed that PPM-DOTS can improve effectiveness while also lowering costs. CONCLUSION: PPM-DOTS can be an affordable and cost-effective approach to improving TB control in India, and can substantially lower the economic burden of TB for patients. PMID:16799727

  8. Modeling the Cost Effectiveness of Malaria Control Interventions in the Highlands of Western Kenya

    PubMed Central

    Stuckey, Erin M.; Stevenson, Jennifer; Galactionova, Katya; Baidjoe, Amrish Y.; Bousema, Teun; Odongo, Wycliffe; Kariuki, Simon; Drakeley, Chris; Smith, Thomas A.; Cox, Jonathan; Chitnis, Nakul

    2014-01-01

    Introduction Tools that allow for in silico optimization of available malaria control strategies can assist the decision-making process for prioritizing interventions. The OpenMalaria stochastic simulation modeling platform can be applied to simulate the impact of interventions singly and in combination as implemented in Rachuonyo South District, western Kenya, to support this goal. Methods Combinations of malaria interventions were simulated using a previously-published, validated model of malaria epidemiology and control in the study area. An economic model of the costs of case management and malaria control interventions in Kenya was applied to simulation results and cost-effectiveness of each intervention combination compared to the corresponding simulated outputs of a scenario without interventions. Uncertainty was evaluated by varying health system and intervention delivery parameters. Results The intervention strategy with the greatest simulated health impact employed long lasting insecticide treated net (LLIN) use by 80% of the population, 90% of households covered by indoor residual spraying (IRS) with deployment starting in April, and intermittent screen and treat (IST) of school children using Artemether lumefantrine (AL) with 80% coverage twice per term. However, the current malaria control strategy in the study area including LLIN use of 56% and IRS coverage of 70% was the most cost effective at reducing disability-adjusted life years (DALYs) over a five year period. Conclusions All the simulated intervention combinations can be considered cost effective in the context of available resources for health in Kenya. Increasing coverage of vector control interventions has a larger simulated impact compared to adding IST to the current implementation strategy, suggesting that transmission in the study area is not at a level to warrant replacing vector control to a school-based screen and treat program. These results have the potential to assist malaria

  9. COST EFFECTIVENESS OF A PHYSICIAN-PHARMACIST COLLABORATION INTERVENTION TO IMPROVE BLOOD PRESSURE CONTROL

    PubMed Central

    Polgreen, Linnea A.; Han, Jayoung; Carter, Barry L.; Ardery, Gail P.; Coffey, Christopher S.; Chrischilles, Elizabeth A.; James, Paul A.

    2015-01-01

    Previous studies have demonstrated the cost-effectiveness of physician-pharmacist collaborations to improve hypertension control. However, most studies have limited generalizability: lacking minority and low-income populations. The Collaboration Among Pharmacist and Physicians to Improve Blood Pressure Now trial randomized 625 patients from 32 medical offices in 15 states. Each office had an existing clinical pharmacist on staff. Pharmacists in intervention offices communicated with patients and made recommendations to physicians about changes in therapy. Demographic information, blood pressure, medications and physician visits were recorded. In addition, pharmacists tracked time spent with each patient. Costs were assigned to medications, and pharmacist and physician time. Cost-effectiveness ratios were calculated based on changes in blood pressure measurements and hypertension-control rates. Thirty-eight percent of patients were black, 14% were Hispanic, and 49% had annual income <$25,000. At 9 months, average systolic blood pressure was 6.1 mm Hg lower (+/− 3.5), diastolic was 2.9 mm Hg lower (+/− 1.9), and the percentage of patients with controlled hypertension was 43% in the intervention group and 34% in the control group. Total costs for the intervention group were $1462.87 (+/− 132.51), and $1259.94 (+/− 183.30) for the control group, a difference of $202.93. The cost to lower blood pressure by 1 mmHg was $33.27 for systolic blood pressure and $69.98 for diastolic blood pressure. The cost to increase the rate of hypertension control by one percentage point in the study population was $22.55. Our results highlight the cost-effectiveness of a clinical pharmacy intervention for hypertension control in primary care settings. PMID:26527048

  10. Cost-Effectiveness of a Physician-Pharmacist Collaboration Intervention to Improve Blood Pressure Control.

    PubMed

    Polgreen, Linnea A; Han, Jayoung; Carter, Barry L; Ardery, Gail P; Coffey, Christopher S; Chrischilles, Elizabeth A; James, Paul A

    2015-12-01

    Previous studies have demonstrated the cost-effectiveness of physician-pharmacist collaborations to improve hypertension control. However, most studies have limited generalizability, lacking minority and low-income populations. The Collaboration Among Pharmacist and Physicians to Improve Blood Pressure Now (CAPTION) trial randomized 625 patients from 32 medical offices in 15 states. Each office had an existing clinical pharmacist on staff. Pharmacists in intervention offices communicated with patients and made recommendations to physicians about changes in therapy. Demographic information, blood pressure (BP), medications, and physician visits were recorded. In addition, pharmacists tracked time spent with each patient. Costs were assigned to medications and pharmacist and physician time. Cost-effectiveness ratios were calculated based on changes in BP measurements and hypertension control rates. Thirty-eight percent of patients were black, 14% were Hispanic, and 49% had annual income <$25 000. At 9 months, average systolic BP was 6.1 mm Hg lower (±3.5), diastolic was 2.9 mm Hg lower (±1.9), and the percentage of patients with controlled hypertension was 43% in the intervention group and 34% in the control group. Total costs for the intervention group were $1462.87 (±132.51) and $1259.94 (±183.30) for the control group, a difference of $202.93. The cost to lower BP by 1 mm Hg was $33.27 for systolic BP and $69.98 for diastolic BP. The cost to increase the rate of hypertension control by 1 percentage point in the study population was $22.55. Our results highlight the cost-effectiveness of a clinical pharmacy intervention for hypertension control in primary care settings. PMID:26527048

  11. Digital flight control systems

    NASA Technical Reports Server (NTRS)

    Caglayan, A. K.; Vanlandingham, H. F.

    1977-01-01

    The design of stable feedback control laws for sampled-data systems with variable rate sampling was investigated. These types of sampled-data systems arise naturally in digital flight control systems which use digital actuators where it is desirable to decrease the number of control computer output commands in order to save wear and tear of the associated equipment. The design of aircraft control systems which are optimally tolerant of sensor and actuator failures was also studied. Detection of the failed sensor or actuator must be resolved and if the estimate of the state is used in the control law, then it is also desirable to have an estimator which will give the optimal state estimate even under the failed conditions.

  12. Digital vibration control techniques

    NASA Technical Reports Server (NTRS)

    Chapman, P.; Kim, B. K.; Boctor, W.

    1974-01-01

    Analog vibration control techniques are reviewed and are compared with digital techniques. The advantages of the digital methods over the analog methods are demonstrated. The following topics are covered: (1) methods of computer-controlled random vibration and reverberation acoustic testing; (2) methods of computer-controlled sinewave vibration testing; and (3) methods of computer-controlled shock testing. Basic concepts are stressed rather than specific techniques or equipment. General algorithms are described in the form of block diagrams and flow diagrams. Specific problems and potential problems are discussed. The material is computer sciences oriented but is kept at a level that facilitates an understanding of the basic concepts of computer-controlled induced environmental test systems.

  13. Development of a cost-effective PC-based motion control system

    SciTech Connect

    Hollar, D.L.

    1998-01-01

    A cost-effective PC-based motion control system was developed and evaluated for use on a laser welding system. The motion system is capable of X-Y simultaneous contouring and provides a rotary axis of motion also. The system motion paths can be specified in either Relative or Absolute motion. The PC controls all of the laser power supply and shutter I/O operations. All of the motion programming and operator interfacing is via the Windows {reg_sign}95 operating system.

  14. Cost-Effectiveness of Catheter Ablation for Rhythm Control of Atrial Fibrillation

    PubMed Central

    Blackhouse, Gord; Assasi, Nazila; Xie, Feng; Gaebel, Kathryn; Campbell, Kaitryn; Healey, Jeff S.; O'Reilly, Daria

    2013-01-01

    Objective. The objective of this study is to evaluate the cost-effectiveness of catheter ablation for rhythm control compared to antiarrhythmic drug (AAD) therapy in patients with atrial fibrillation (AF) who have previously failed on an AAD. Methods. An economic model was developed to compare (1) catheter ablation and (2) AAD (amiodarone 200 mg/day). At the end of the initial 12 month phase of the model, patients are classified as being in normal sinus rhythm or with AF, based on data from a meta-analysis. In the 5-year Markov phase of the model, patients are at risk of ischemic stroke each 3-month model cycle. Results. The model estimated that, compared to the AAD strategy, ablation had $8,539 higher costs, 0.033 fewer strokes, and 0.144 more QALYS over the 5-year time horizon. The incremental cost per QALY of ablation compared to AAD was estimated to be $59,194. The probability of ablation being cost-effective for willingness to pay thresholds of $50,000 and $100,000 was estimated to be 0.89 and 0.90, respectively. Conclusion. Based on current evidence, pulmonary vein ablation for treatment of AF is cost-effective if decision makers willingness to pay for a QALY is $59,194 or higher. PMID:24089640

  15. Digital numerically controlled oscillator

    NASA Technical Reports Server (NTRS)

    Cellier, A.; Huey, D. C.; Ma, L. N. (Inventor)

    1980-01-01

    The frequency and phase of an output signal from an oscillator circuit are controlled with accuracy by a digital input word. Positive and negative alterations in output frequency are both provided for by translating all values of input words so that they are positive. The oscillator reference frequency is corrected only in one direction, by adding phase to the output frequency of the oscillator. The input control word is translated to a single algebraic sign and the digital 1 is added thereto. The translated input control word is then accumulated. A reference clock signal having a frequency at an integer multiple of the desired frequency of the output signal is generated. The accumulated control word is then compared with a threshold level. The output signal is adjusted in a single direction by dividing the frequency of the reference clock signal by a first integer or by an integer different from the first integer.

  16. A Cost-Effectiveness Tool for Informing Policies on Zika Virus Control

    PubMed Central

    Tamagnan, Jules A.; Medlock, Jan; Ndeffo-Mbah, Martial L.; Fish, Durland; Ávila-Agüero, María L.; Marín, Rodrigo; Ko, Albert I.; Galvani, Alison P.

    2016-01-01

    Background As Zika virus continues to spread, decisions regarding resource allocations to control the outbreak underscore the need for a tool to weigh policies according to their cost and the health burden they could avert. For example, to combat the current Zika outbreak the US President requested the allocation of $1.8 billion from Congress in February 2016. Methodology/Principal Findings Illustrated through an interactive tool, we evaluated how the number of Zika cases averted, the period during pregnancy in which Zika infection poses a risk of microcephaly, and probabilities of microcephaly and Guillain-Barré Syndrome (GBS) impact the cost at which an intervention is cost-effective. From Northeast Brazilian microcephaly incidence data, we estimated the probability of microcephaly in infants born to Zika-infected women (0.49% to 2.10%). We also estimated the probability of GBS arising from Zika infections in Brazil (0.02% to 0.06%) and Colombia (0.08%). We calculated that each microcephaly and GBS case incurs the loss of 29.95 DALYs and 1.25 DALYs per case, as well as direct medical costs for Latin America and the Caribbean of $91,102 and $28,818, respectively. We demonstrated the utility of our cost-effectiveness tool with examples evaluating funding commitments by Costa Rica and Brazil, the US presidential proposal, and the novel approach of genetically modified mosquitoes. Our analyses indicate that the commitments and the proposal are likely to be cost-effective, whereas the cost-effectiveness of genetically modified mosquitoes depends on the country of implementation. Conclusions/Significance Current estimates from our tool suggest that the health burden from microcephaly and GBS warrants substantial expenditures focused on Zika virus control. Our results justify the funding committed in Costa Rica and Brazil and many aspects of the budget outlined in the US president’s proposal. As data continue to be collected, new parameter estimates can be customized

  17. Cost-effectiveness of Novel System of Mosquito Surveillance and Control, Brazil

    PubMed Central

    Pepin, Kim M.; Marques-Toledo, Cecilia; Scherer, Luciano; Morais, Maira M.; Ellis, Brett

    2013-01-01

    Of all countries in the Western Hemisphere, Brazil has the highest economic losses caused by dengue fever. We evaluated the cost-effectiveness of a novel system of vector surveillance and control, Monitoramento Inteligente da Dengue (Intelligent Dengue Monitoring System [MID]), which was implemented in 21 cities in Minas Gerais, Brazil. Traps for adult female mosquitoes were spaced at 300-m intervals throughout each city. In cities that used MID, vector control was conducted specifically at high-risk sites (indicated through daily updates by MID). In control cities, vector control proceeded according to guidelines of the Brazilian government. We estimated that MID prevented 27,191 cases of dengue fever and saved an average of $227 (median $58) per case prevented, which saved approximately $364,517 in direct costs (health care and vector control) and $7,138,940 in lost wages (societal effect) annually. MID was more effective in cities with stronger economies and more cost-effective in cities with higher levels of mosquito infestation. PMID:23628282

  18. Intervention Costs and Cost-Effectiveness of a Successful Telephonic Intervention to Promote Diabetes Control

    PubMed Central

    Schechter, Clyde B.; Cohen, Hillel W.; Shmukler, Celia; Walker, Elizabeth A.

    2012-01-01

    OBJECTIVE To characterize the costs and cost-effectiveness of a telephonic behavioral intervention to promote glycemic control in the Improving Diabetes Outcomes study. RESEARCH DESIGN AND METHODS Using the provider perspective and a time horizon to the end of the 1-year intervention, we calculate the costs of a telephonic intervention by health educators compared with an active control (print) intervention to improve glycemic control in adults with type 2 diabetes. We calculate the cost-effectiveness ratios for a reduction of one percentage point in hemoglobin A1c (A1C), as well as for one participant to achieve an A1C <7%. Base-case and sensitivity analysis results are presented. RESULTS The intervention cost $176.61 per person randomized to the telephone group to achieve a mean 0.36 percentage point of A1C improvement. The incremental cost-effectiveness ratio was $490.58 per incremental percentage point of A1C improvement and $2,617.35 per person over a 1-year intervention in achieving the A1C goal. In probabilistic sensitivity analysis, the median (interquartile range) of per capita cost, cost per percentage point reduction in A1C, and cost per person achieving the A1C goal of <7% are $175.82 (147.32–203.56), $487.75 (356.50–718.32), and $2,312.88 (1,785.58–3,220.78), respectively. CONCLUSIONS The costs of a telephonic intervention for diabetes self-management support are moderate and commensurate to the modest associated improvement in glycemic control. PMID:22851599

  19. Cost-Effectiveness of Chagas Disease Vector Control Strategies in Northwestern Argentina

    PubMed Central

    Vazquez-Prokopec, Gonzalo M.; Spillmann, Cynthia; Zaidenberg, Mario; Kitron, Uriel; Gürtler, Ricardo E.

    2009-01-01

    Background Control and prevention of Chagas disease rely mostly on residual spraying of insecticides. In Argentina, vector control shifted from a vertical to a fully horizontal strategy based on community participation between 1992 and 2004. The effects of such strategy on Triatoma infestans, the main domestic vector, and on disease transmission have not been assessed. Methods and Findings Based on retrospective (1993–2004) records from the Argentinean Ministry of Health for the Moreno Department, Northwestern Argentina, we performed a cost-effectiveness (CE) analysis and compared the observed CE of the fully horizontal vector control strategy with the expected CE for a vertical or a mixed (i.e., vertical attack phase followed by horizontal surveillance) strategy. Total direct costs (in 2004 US$) of the horizontal and mixed strategies were, respectively, 3.3 and 1.7 times lower than the costs of the vertical strategy, due to reductions in personnel costs. The estimated CE ratios for the vertical, mixed and horizontal strategies were US$132, US$82 and US$45 per averted human case, respectively. When per diems were excluded from the costs (i.e., simulating the decentralization of control activities), the CE of vertical, mixed and horizontal strategies was reduced to US$60, US$42 and US$32 per averted case, respectively. Conclusions and Significance The mixed strategy would have averted between 1.6 and 4.0 times more human cases than the fully horizontal strategy, and would have been the most cost-effective option to interrupt parasite transmission in the Department. In rural and dispersed areas where waning vertical vector programs cannot accomplish full insecticide coverage, alternative strategies need to be developed. If properly implemented, community participation represents not only the most appealing but also the most cost-effective alternative to accomplish such objectives. PMID:19156190

  20. Digitally Controlled Beam Attenuator

    NASA Astrophysics Data System (ADS)

    Peppler, W. W.; Kudva, B.; Dobbins, J. T.; Lee, C. S.; Van Lysel, M. S.; Hasegawa, B. H.; Mistretta, C. A.

    1982-12-01

    In digital fluorographic techniques the video camera must accommodate a wide dynamic range due to the large variation in the subject thickness within the field of view. Typically exposure factors and the optical aperture are selected such that the maximum video signal is obtained in the most transmissive region of the subject. Consequently, it has been shown that the signal-to-noise ratio is severely reduced in the dark regions. We have developed a prototype digital beam attenuator (DBA) which will alleviate this and some related problems in digital fluorography. The prototype DBA consists of a 6x6 array of pistons which are individually controlled. A membrane containing an attenuating solu-tion of (CeC13) in water and the piston matrix are placed between the x-ray tube and the subject. Under digital control the pistons are moved into the attenuating material in order to adjust the beam intensity over each of the 36 cells. The DBA control unit which digitizes the image during patient positioning will direct the pistons under hydraulic control to produce a uniform x-ray field exiting the subject. The pistons were designed to produce very little structural background in the image. In subtraction studies any structure would be cancelled. For non-subtraction studies such as cine-cardiology we are considering higher cell densities (eg. 64x64). Due to the narrow range of transmission provided by the DBA, in such studies ultra-high contrast films could be used to produce a high resolution quasi-subtraction display. Additional benefits of the DBA are: 1) reduced dose to the bright image areas when the dark areas are properly exposed. 2) improved scatter and glare to primary ratios, leading to improved contrast in the dark areas.

  1. Controlling air pollution from passenger ferries: cost-effectiveness of seven technological options.

    PubMed

    Farrell, Alexander E; Corbett, James J; Winebrake, James J

    2002-12-01

    Continued interest in improving air quality in the United States along with renewed interest in the expansion of urban passenger ferry service has created concern about air pollution from ferry vessels. This paper presents a methodology for estimating the air pollution emissions from passenger ferries and the costs of emissions control strategies. The methodology is used to estimate the emissions and costs of retrofitting or re-powering ferries with seven technological options (combinations of propulsion and emission control systems) onto three vessels currently in service in San Francisco Bay. The technologies include improved engine design, cleaner fuels (including natural gas), and exhaust gas cleanup devices. The three vessels span a range of ages and technologies, from a 25-year-old monohull to a modern, high-speed catamaran built only four years ago. By looking at a range of technologies, vessel designs, and service conditions, a sense of the broader implications of controlling emissions from passenger ferries across a range of vessels and service profiles is provided. Tier 2-certified engines are the most cost-effective choice, but all options are cost-effective relative to other emission control strategies already in place in the transportation system. PMID:12540045

  2. Analysis of U.S. produced water controls -- Are they cost-effective?

    SciTech Connect

    Veil, J.A.

    1995-12-31

    The US Environmental Protection Agency (EPA) establishes controls on produced water discharges into US waters through effluent limitations guidelines (ELGs), and general and individual discharge permits. Over the past 20 years, produced water controls have become much stricter, and in some areas, no discharge of produced water is allowed. In setting discharge standards, EPA considers vast amounts of data, makes assumptions regarding which data and what approaches are representative, selects the most appropriate analytical methods, and interprets the analytical results. Despite EPA`s considerable efforts to accurately understand and characterize the economic and environmental impacts of produced water discharges before proposing and adopting ELGs and issuing permits, current US produced water controls may be overly restrictive and not cost-effective. This paper summarizes several studies that have reviewed in detail EPA`s data, assumptions, and analytical methods for earlier proposed regulations and general permits. These include the offshore oil and gas ELGs, EPA`s Region 6 general permit for coastal waters, and most recently, the proposed ELGs for the coastal oil and gas industry. By substituting different data, using revised assumptions, and reanalyzing data that are equally or more valid, the studies reach alternate conclusions on the cost-effectiveness of current produced water controls.

  3. Cost-effectiveness analysis of a state funded programme for control of severe asthma

    PubMed Central

    Franco, Rosana; Santos, Andreia C; do Nascimento, Harrison F; Souza-Machado, Carolina; Ponte, Eduardo; Souza-Machado, Adelmir; Loureiro, Sebastião; Barreto, Maurício L; Rodrigues, Laura C; Cruz, Alvaro A

    2007-01-01

    Background Asthma is one of the most common chronic diseases and a major economical burden to families and health systems. Whereas efficacy of current therapeutical options has been clearly established, cost-effectiveness analysis of public health interventions for asthma control are scarce. Methods 81 patients with severe asthma (12–75 years) joining a programme in a reference clinic providing free asthma medication were asked retrospectively about costs and events in the previous 12 months. During 12 months after joining the programme, information on direct and indirect costs, asthma control by lung function, symptoms and quality of life were collected. The information obtained was used to estimate cost-effectiveness of the intervention as compared to usual public health asthma management. Sensitivity analysis was conducted. Results 64 patients concluded the study. During the 12-months follow-up within the programme, patients had 5 fewer days of hospitalization and 68 fewer visits to emergency/non scheduled medical visits per year, on average. Asthma control scores improved by 50% and quality of life by 74%. The annual saving in public resources was US$387 per patient. Family annual income increased US$512, and family costs were reduced by US$733. Conclusion A programme for control of severe asthma in a developing country can reduce morbidity, improve quality of life and save resources from the health system and patients families. PMID:17509137

  4. Efficacy and cost-effectiveness of environmental management for malaria control.

    PubMed

    Utzinger, J; Tozan, Y; Singer, B H

    2001-09-01

    Roll back malaria (RBM) aims at halving the current burden of the disease by the year 2010. The focus is on sub-Saharan Africa, and it is proposed to implement efficacious and cost-effective control strategies. But the evidence base of such information is scarce, and a notable missing element is the discussion of the potential of environmental management. We reviewed the literature and identified multiple malaria control programmes that incorporated environmental management as the central feature. Prominent among them are programmes launched in 1929 and implemented for two decades at copper mining communities in Zambia. The full package of control measures consisted of vegetation clearance, modification of river boundaries, draining swamps, oil application to open water bodies and house screening. Part of the population also was given quinine and was sleeping under mosquito nets. Monthly malaria incidence rates and vector densities were used for surveillance and adaptive tuning of the environmental management strategies to achieve a high level of performance. Within 3-5 years, malaria-related mortality, morbidity and incidence rates were reduced by 70-95%. Over the entire 20 years of implementation, the programme had averted an estimated 4173 deaths and 161,205 malaria attacks. The estimated costs per death and malaria attack averted were US$ 858 and US$ 22.20, respectively. Over the initial 3-5 years start-up period, analogous to the short-duration of cost-effectiveness analyses of current studies, we estimated that the costs per disability adjusted life year (DALY) averted were US$ 524-591. However, the strategy has a track record of becoming cost-effective in the longer term, as maintenance costs were much lower: US$ 22-92 per DALY averted. In view of fewer adverse ecological effects, increased sustainability and better uses of local resources and knowledge, environmental management--integrated with pharmacological, insecticidal and bednet interventions

  5. Cost-effectiveness of community health workers in tuberculosis control in Bangladesh.

    PubMed Central

    Islam, Md Akramul; Wakai, Susumu; Ishikawa, Nobukatsu; Chowdhury, A. M. R.; Vaughan, J. Patrick

    2002-01-01

    OBJECTIVE: To compare the cost-effectiveness of the tuberculosis (TB) programme run by the Bangladesh Rural Advancement Committee (BRAC), which uses community health workers (CHWs), with that of the government TB programme which does not use CHWs. METHODS: TB control statistics and cost data for July 1996 - June 1997 were collected from both government and BRAC thanas (subdistricts) in rural Bangladesh. To measure the cost per patient cured, total costs were divided by the total number of patients cured. FINDINGS: In the BRAC and government areas, respectively, a total of 186 and 185 TB patients were identified over one year, with cure rates among sputum-positive patients of 84% and 82%. However, the cost per patient cured was US$ 64 in the BRAC area compared to US$ 96 in the government area. CONCLUSION: The government programme was 50% more expensive for similar outcomes. Although both the BRAC and government TB control programmes appeared to achieve satisfactory cure rates using DOTS (a five-point strategy), the involvement of CHWs was found to be more cost-effective in rural Bangladesh. With the same budget, the BRAC programme could cure three TB patients for every two in the government programme. PMID:12132000

  6. Using counterfactuals to evaluate the cost-effectiveness of controlling biological invasions.

    PubMed

    McConnachie, Matthew M; van Wilgen, Brian W; Ferraro, Paul J; Forsyth, Aurelia T; Richardson, David M; Gaertner, Mirijam; Cowling, Richard M

    2016-03-01

    Prioritizing limited conservation funds for controlling biological invasions requires accurate estimates of the effectiveness of interventions to remove invasive species and their cost-effectiveness (cost per unit area or individual). Despite billions of dollars spent controlling biological invasions worldwide, it is unclear whether those efforts are effective, and cost-effective. The paucity of evidence results from the difficulty in measuring the effect of invasive species removal: a researcher must estimate the difference in outcomes (e.g. invasive species cover) between where the removal program intervened and what might have been observed if the program had not intervened. In the program evaluation literature, this is called a counterfactual analysis, which formally compares what actually happened and what would have happened in the absence of an intervention. When program implementation is not randomized, estimating counterfactual outcomes is especially difficult. We show how a thorough understanding of program implementation, combined with a matching empirical design can improve the way counterfactual outcomes are estimated in nonexperimental contexts. As a practical demonstration, we estimated the cost-effectiveness of South Africa's Working for Water program, arguably the world's most ambitious invasive species control program, in removing invasive alien trees from different land use types, across a large area in the Cape Floristic Region. We estimated that the proportion of the treatment area covered by invasive trees would have been 49% higher (5.5% instead of 2.7% of the grid cells occupied) had the program not intervened. Our estimates of cost per hectare to remove invasive species, however, are three to five times higher than the predictions made when the program was initiated. Had there been no control (counter-factual), invasive trees would have spread on untransformed land, but not on land parcels containing plantations or land transformed by

  7. Spatially-Distributed Cost-Effectiveness Analysis Framework to Control Phosphorus from Agricultural Diffuse Pollution.

    PubMed

    Geng, Runzhe; Wang, Xiaoyan; Sharpley, Andrew N; Meng, Fande

    2015-01-01

    Best management practices (BMPs) for agricultural diffuse pollution control are implemented at the field or small-watershed scale. However, the benefits of BMP implementation on receiving water quality at multiple spatial is an ongoing challenge. In this paper, we introduce an integrated approach that combines risk assessment (i.e., Phosphorus (P) index), model simulation techniques (Hydrological Simulation Program-FORTRAN), and a BMP placement tool at various scales to identify the optimal location for implementing multiple BMPs and estimate BMP effectiveness after implementation. A statistically significant decrease in nutrient discharge from watersheds is proposed to evaluate the effectiveness of BMPs, strategically targeted within watersheds. Specifically, we estimate two types of cost-effectiveness curves (total pollution reduction and proportion of watersheds improved) for four allocation approaches. Selection of a ''best approach" depends on the relative importance of the two types of effectiveness, which involves a value judgment based on the random/aggregated degree of BMP distribution among and within sub-watersheds. A statistical optimization framework is developed and evaluated in Chaohe River Watershed located in the northern mountain area of Beijing. Results show that BMP implementation significantly (p >0.001) decrease P loss from the watershed. Remedial strategies where BMPs were targeted to areas of high risk of P loss, deceased P loads compared with strategies where BMPs were randomly located across watersheds. Sensitivity analysis indicated that aggregated BMP placement in particular watershed is the most cost-effective scenario to decrease P loss. The optimization approach outlined in this paper is a spatially hierarchical method for targeting nonpoint source controls across a range of scales from field to farm, to watersheds, to regions. Further, model estimates showed targeting at multiple scales is necessary to optimize program efficiency

  8. Safe and cost-effective control of post-transplantation recurrence of hepatitis B

    PubMed Central

    Takaki, Akinobu; Yagi, Takahito; Yamamoto, Kazuhide

    2015-01-01

    A combination of hepatitis B immunoglobulin (HBIG) and nucleoside/nucleotide analogs (NUC) is the current standard of care for controlling hepatitis B recurrence after orthotopic liver transplantation (OLT). However, long-term HBIG administration is associated with several unresolved issues, including limited availability and extremely high cost, and thus several protocols for treatment with low-dose HBIG combined with NUC or HBIG-free regimens have been developed. This article reviews recent advances in post-OLT hepatitis B virus (HBV) control and future methodological directions. New NUC such as entecavir, tenofovir or lamivudine plus adefovir dipivoxil combinations induce a very low frequency of viral resistance. The withdrawal of HBIG after several months of OLT under new NUC continuation also has permissible effects. Even after HBV reactivation, NUC can usually achieve viral control when viral markers are strictly followed up. Another approach is to induce self-producing anti-HBV antibodies via vaccination with a hepatitis B surface antigen vaccine. However, HBV vaccination is not sufficiently effective in patients to treat liver cirrhosis type B after OLT because immune tolerance to the virus has already continued for several decades. Trials of its safety and cost-effectiveness are required. This review advocates a safe and economical approach to controlling post-OLT HBV recurrence. PMID:24905970

  9. Safe and cost-effective control of post-transplantation recurrence of hepatitis B.

    PubMed

    Takaki, Akinobu; Yagi, Takahito; Yamamoto, Kazuhide

    2015-01-01

    A combination of hepatitis B immunoglobulin (HBIG) and nucleoside/nucleotide analogs (NUC) is the current standard of care for controlling hepatitis B recurrence after orthotopic liver transplantation (OLT). However, long-term HBIG administration is associated with several unresolved issues, including limited availability and extremely high cost, and thus several protocols for treatment with low-dose HBIG combined with NUC or HBIG-free regimens have been developed. This article reviews recent advances in post-OLT hepatitis B virus (HBV) control and future methodological directions. New NUC such as entecavir, tenofovir or lamivudine plus adefovir dipivoxil combinations induce a very low frequency of viral resistance. The withdrawal of HBIG after several months of OLT under new NUC continuation also has permissible effects. Even after HBV reactivation, NUC can usually achieve viral control when viral markers are strictly followed up. Another approach is to induce self-producing anti-HBV antibodies via vaccination with a hepatitis B surface antigen vaccine. However, HBV vaccination is not sufficiently effective in patients to treat liver cirrhosis type B after OLT because immune tolerance to the virus has already continued for several decades. Trials of its safety and cost-effectiveness are required. This review advocates a safe and economical approach to controlling post-OLT HBV recurrence. PMID:24905970

  10. Modelling geographic variation in the cost-effectiveness of control policies for infectious vector diseases: the example of Chagas disease.

    PubMed

    Castillo-Riquelme, Marianela; Chalabi, Zaid; Lord, Joanne; Guhl, Felipe; Campbell-Lendrum, Diarmid; Davies, Clive; Fox-Rushby, Julia

    2008-03-01

    Few cost-effectiveness analysis (CEA) models have accounted for geographic variation in input parameters. This paper describes a deterministic discrete-time multi-state model to estimate the cost-effectiveness of vector control policies for Chagas disease, where implementation varies according to village characteristics. The model outputs include the total number of new infections, disability adjusted life years (DALYs) incurred, costs of associated healthcare, and total costs of the Ministry of Health's control policy for house surveillance and spraying. Incremental net benefits were estimated to determine Colombian villages in which it is cost-effective to implement the control policy. The robustness of these conclusions was evaluated by deterministic sensitivity analyses. The model should help provide a decision-support system to compare control policies and to allocate resources geographically. PMID:18222556

  11. Impact and Cost-Effectiveness of a Comprehensive Schistosomiasis japonica Control Program in the Poyang Lake Region of China

    PubMed Central

    Yu, Qing; Zhao, Geng-Ming; Hong, Xian-Lin; Lutz, Eric A.; Guo, Jia-Gang

    2013-01-01

    Schistosomiasis japonica remains a significant public-health problem in China. This study evaluated cost-effectiveness of a comprehensive schistosomiasis control program (2003–2006). The comprehensive control program was implemented in Zhangjia and Jianwu (cases); while standard interventions continued in Koutou and Xiajia (controls). Incurred costs were documented and the schistosomiasis comprehensive impact index (SCI) and cost-effectiveness ratio (Comprehensive Control Program Cost/SCI) were applied. In 2003, prevalence of Schistosoma japonicum infection was 11.3% (Zhangjia), 6.7% (Jianwu), 6.5% (Koutou), and 8.0% (Xiajia). In 2006, the comprehensive control program in Zhangjia and Jianwu reduced infection to 1.6% and 0.6%, respectively; while Koutou and Xiajia had a schistosomiasis prevalence of 3.2% and 13.0%, respectively. The year-by-year SCIs in Zhangjia were 0.28, 105.25, and 47.58, with an overall increase in cost-effectiveness ratio of 374.9%–544.8%. The SCIs in Jianwu were 16.21, 52.95, and 149.58, with increase in cost-effectiveness of 226.7%–1,149.4%. Investment in Koutou and Xiajia remained static (US$10,000 unit cost). The comprehensive control program implemented in the two case villages reduced median prevalence of schistosomiasis 8.5-fold. Further, the cost effectiveness ratio demonstrated that the comprehensive control program was 170% (Zhangjia) and 922.7% (Jianwu) more cost-effective. This work clearly shows the improvements in both cost and disease prevention effectiveness that a comprehensive control program-approach has on schistosomiasis infection prevalence. PMID:24287861

  12. Impact and cost-effectiveness of a comprehensive Schistosomiasis japonica control program in the Poyang Lake region of China.

    PubMed

    Yu, Qing; Zhao, Geng-Ming; Hong, Xian-Lin; Lutz, Eric A; Guo, Jia-Gang

    2013-12-01

    Schistosomiasis japonica remains a significant public-health problem in China. This study evaluated cost-effectiveness of a comprehensive schistosomiasis control program (2003-2006). The comprehensive control program was implemented in Zhangjia and Jianwu (cases); while standard interventions continued in Koutou and Xiajia (controls). Incurred costs were documented and the schistosomiasis comprehensive impact index (SCI) and cost-effectiveness ratio (Comprehensive Control Program Cost/SCI) were applied. In 2003, prevalence of Schistosoma japonicum infection was 11.3% (Zhangjia), 6.7% (Jianwu), 6.5% (Koutou), and 8.0% (Xiajia). In 2006, the comprehensive control program in Zhangjia and Jianwu reduced infection to 1.6% and 0.6%, respectively; while Koutou and Xiajia had a schistosomiasis prevalence of 3.2% and 13.0%, respectively. The year-by-year SCIs in Zhangjia were 0.28, 105.25, and 47.58, with an overall increase in cost-effectiveness ratio of 374.9%-544.8%. The SCIs in Jianwu were 16.21, 52.95, and 149.58, with increase in cost-effectiveness of 226.7%-1,149.4%. Investment in Koutou and Xiajia remained static (US$10,000 unit cost). The comprehensive control program implemented in the two case villages reduced median prevalence of schistosomiasis 8.5-fold. Further, the cost effectiveness ratio demonstrated that the comprehensive control program was 170% (Zhangjia) and 922.7% (Jianwu) more cost-effective. This work clearly shows the improvements in both cost and disease prevention effectiveness that a comprehensive control program-approach has on schistosomiasis infection prevalence. PMID:24287861

  13. Cost-effectiveness of novel vaccines for tuberculosis control: a decision analysis study

    PubMed Central

    2011-01-01

    Background The development of a successful new tuberculosis (TB) vaccine would circumvent many limitations of current diagnostic and treatment practices. However, vaccine development is complex and costly. We aimed to assess the potential cost effectiveness of novel vaccines for TB control in a sub-Saharan African country - Zambia - relative to the existing strategy of directly observed treatment, short course (DOTS) and current level of bacille Calmette-Guérin (BCG) vaccination coverage. Methods We conducted a decision analysis model-based simulation from the societal perspective, with a 3% discount rate and all costs expressed in 2007 US dollars. Health outcomes and costs were projected over a 30-year period, for persons born in Zambia (population 11,478,000 in 2005) in year 1. Initial development costs for single vaccination and prime-boost strategies were prorated to the Zambian share (0.398%) of global BCG vaccine coverage for newborns. Main outcome measures were TB-related morbidity, mortality, and costs over a range of potential scenarios for vaccine efficacy. Results Relative to the status quo strategy, a BCG replacement vaccine administered at birth, with 70% efficacy in preventing rapid progression to TB disease after initial infection, is estimated to avert 932 TB cases and 422 TB-related deaths (prevention of 199 cases/100,000 vaccinated, and 90 deaths/100,000 vaccinated). This would result in estimated net savings of $3.6 million over 30 years for 468,073 Zambians born in year 1 of the simulation. The addition of a booster at age 10 results in estimated savings of $5.6 million compared to the status quo, averting 1,863 TB cases and 1,011 TB-related deaths (prevention of 398 cases/100,000 vaccinated, and of 216 deaths/100,000 vaccinated). With vaccination at birth alone, net savings would be realized within 1 year, whereas the prime-boost strategy would require an additional 5 years to realize savings, reflecting a greater initial development cost

  14. Cost effectiveness of abatement options for emissions control in Egyptian iron foundries

    SciTech Connect

    Rabah, M.A. . Industrial Wastes Lab.)

    1999-01-01

    This study focuses on an evaluation of the cost effectiveness of abatement options for controlling emissions in existing iron foundries in Egypt. It is expected that such a study will enable decision by identifying concrete measures for abating total solid emissions (TSP). The structure of iron foundries in the country have been surveyed and the variant types of furnaces, the TSP emission level without any abatement options and data of the annual turnover of these foundries have been obtained. Possible market based instruments (MBI) options that might encourage these firms to seek the most efficient control measures have also been examined. Different abatement options such as updating burner design, switching heavy fuel oil to kerosene or natural gas, installing cleaning systems and/or updating the process technology were tested in terms of emission level and the overall turnover. The effect of installing different cleaning systems such as wet scrubbers and filter bags on the running cost of abating TSP was also investigated. Results obtained reveal that crucible (CrF) and short rotary (SRF) furnaces are the most numerous types of plants in Egypt. The concentration of TSP emissions exceeds the standards as specified in Law. Poor quality scrap input adversely affects the operation of the furnace, and impairs product quality and causes excessive TSP emissions. TSP emissions per ton of cast iron produced are relatively low for induction furnaces (EIFs), and very high in the dirtier technologies, particularly CrF and SRF. Cost analysis shows that the cost of abating one ton of TSP emitted amounts to 3000--5000 L.E and this cost represents a high percentage of turnover to plants abating emissions.

  15. Cognitive-behavioral treatment for panic disorder with agoraphobia: a randomized, controlled trial and cost-effectiveness analysis.

    PubMed

    Roberge, Pasquale; Marchand, André; Reinharz, Daniel; Savard, Pierre

    2008-05-01

    A randomized, controlled trial was conducted to examine the cost-effectiveness of cognitive-behavioral treatment (CBT) for panic disorder with agoraphobia. A total of 100 participants were randomly assigned to standard (n = 33), group (n = 35), and brief (n = 32) treatment conditions. Results show significant clinical and statistical improvement on standard symptom measures and quality of life from baseline to posttreatment and 3-month follow-up, with no significant differences between treatment conditions. Compared with standard CBT, brief and group CBT incurred lower treatment costs and had a superior cost-effectiveness ratio, suggesting the potential of these alternative treatment conditions in increasing access to effective treatment. PMID:18391051

  16. Cost-Effectiveness of a Hypertension Control Intervention in Three Community Health Centers in China

    PubMed Central

    Bai, Yamin; Zhao, Yanfang; Wang, Guijing; Wang, Huicheng; Liu, Kejun; Zhao, Wenhua

    2015-01-01

    Background Hypertension and associated chronic diseases impose enormous and growing health and economic burdens worldwide. The objective of this study was to investigate the cost-effectiveness (CE) of a hypertension control program in China. Methods We collected information on program costs and health outcomes in three community health centers over a 1-year period. The participants were 4902 people with hypertension (systolic blood pressure [SBP] ≥140 mm Hg and/ or diastolic blood pressure [DBP] ≥90 mm Hg, or on hypertension medication) aged 18 years and older. The SBP and DBP changes in the populations were estimated from a random sample of 818 participants by conducting face-to-face interviews and physical examinations. We derived CE measures based on the costs and effects on health outcomes. Findings The total cost of implementing the intervention was Renminbi (RMB) 240 772 yuan (US$35 252), or 49 yuan (US$7.17) per participant in 2009. On average, SBP decreased from 143 to 131 mm Hg (P < .001) and DBP decreased from 84 to 78 mm Hg (P < .001), the SBP decreases ranged from 7.6 to 17.8 mm Hg and DBP decreases ranged from 3.9 to 8.3 mm Hg. CE ratios ranged from RMB 3.6 to 5.0 yuan (US$0.53-US$0.73) per person per mm Hg SBP decrease, and from RMB 6.3 to 9.7 yuan (US$0.92-US$1.42) per person per mm Hg DBP decrease. Interpretation Per capita costs varied widely across the communities, as did changes in SBP and DBP, but CE was similar. The findings suggest (a) a positive correlation between per capita costs and program effectiveness, (b) differences in intervention levels, and (c) differences in health status. CE results could be helpful to policy makers in making resource allocation decisions. PMID:23799707

  17. Cost-effectiveness analysis of interventions for tuberculosis control: DALYs versus QALYs.

    PubMed

    Diel, R; Lampenius, N

    2014-07-01

    The emergence of multi-drug-resistant tuberculosis (MDR-TB) in the European region and the high costs (nearly 536 million) generated by the nearly 72,000 notified TB cases in the EU are the factors driving the need for development and implementation of new tools against TB. In this context, cost-effectiveness analyses applying quality-adjusted life-years (QALYs) or disability-adjusted life-years (DALYs) as outcome measures for economic evaluation of improved approaches to TB control are increasingly important. While the methodology applied to derive the effectiveness data is commonly reported, less information is given regarding the derivation of utility weights in the calculation of QALYs for TB treatment. To date, despite the particular complexities of the disease, TB health effects have not been fully measured and there is no agreement on how disutility of TB disease should be accounted for. Consequently, disutility values in published studies vary considerably, and often appear to lack empirical evidence. As the need for a solid heath-economics rationale for investment in new tools against TB grows, adequate and comprehensive methods for assessing the impairments caused by different types of TB must be developed. Focusing on the assessment of DALYs as a measure of outcome in economic evaluation, we have built an exemplary model calculation applying the original TB data for Germany as reported to the Robert Koch Institute. Our work demonstrates that the use of standard equations provided in the scientific literature probably results in an underestimation of lost DALYs compared with probabilistic techniques. Providing distributions around epidemiological averages, coupled with Monte Carlo simulation to address uncertainty, may result in more realistic values. In line with a previous recommendation by the World Health Organization, it appears worthwhile to consider this more intricate approach to providing healthcare resource allocation decisions

  18. Cognitive-Behavioral Treatment for Panic Disorder with Agoraphobia: A Randomized, Controlled Trial and Cost-Effectiveness Analysis

    ERIC Educational Resources Information Center

    Roberge, Pasquale; Marchand, Andre; Reinharz, Daniel; Savard, Pierre

    2008-01-01

    A randomized, controlled trial was conducted to examine the cost-effectiveness of cognitive-behavioral treatment (CBT) for panic disorder with agoraphobia. A total of 100 participants were randomly assigned to standard (n = 33), group (n = 35), and brief (n = 32) treatment conditions. Results show significant clinical and statistical improvement…

  19. Cost-Effectiveness of Breast Cancer Control Strategies in Central America: The Cases of Costa Rica and Mexico

    PubMed Central

    Niëns, Laurens M.; Zelle, Sten G.; Gutiérrez-Delgado, Cristina; Rivera Peña, Gustavo; Hidalgo Balarezo, Blanca Rosa; Rodriguez Steller, Erick; Rutten, Frans F. H.

    2014-01-01

    This paper reports the most cost-effective policy options to support and improve breast cancer control in Costa Rica and Mexico. Total costs and effects of breast cancer interventions were estimated using the health care perspective and WHO-CHOICE methodology. Effects were measured in disability-adjusted life years (DALYs) averted. Costs were assessed in 2009 United States Dollars (US$). To the extent available, analyses were based on locally obtained data. In Costa Rica, the current strategy of treating breast cancer in stages I to IV at a 80% coverage level seems to be the most cost-effective with an incremental cost-effectiveness ratio (ICER) of US$4,739 per DALY averted. At a coverage level of 95%, biennial clinical breast examination (CBE) screening could improve Costa Rica's population health twofold, and can still be considered very cost-effective (ICER US$5,964/DALY). For Mexico, our results indicate that at 95% coverage a mass-media awareness raising program (MAR) could be the most cost-effective (ICER US$5,021/DALY). If more resources are available in Mexico, biennial mammography screening for women 50–70 yrs (ICER US$12,718/DALY), adding trastuzumab (ICER US$13,994/DALY) or screening women 40–70 yrs biennially plus trastuzumab (ICER US$17,115/DALY) are less cost-effective options. We recommend both Costa Rica and Mexico to engage in MAR, CBE or mammography screening programs, depending on their budget. The results of this study should be interpreted with caution however, as the evidence on the intervention effectiveness is uncertain. Also, these programs require several organizational, budgetary and human resources, and the accessibility of breast cancer diagnostic, referral, treatment and palliative care facilities should be improved simultaneously. A gradual implementation of early detection programs should give the respective Ministries of Health the time to negotiate the required budget, train the required human resources and understand possible

  20. Cost-effectiveness of breast cancer control strategies in Central America: the cases of Costa Rica and Mexico.

    PubMed

    Niëns, Laurens M; Zelle, Sten G; Gutiérrez-Delgado, Cristina; Rivera Peña, Gustavo; Hidalgo Balarezo, Blanca Rosa; Rodriguez Steller, Erick; Rutten, Frans F H

    2014-01-01

    This paper reports the most cost-effective policy options to support and improve breast cancer control in Costa Rica and Mexico. Total costs and effects of breast cancer interventions were estimated using the health care perspective and WHO-CHOICE methodology. Effects were measured in disability-adjusted life years (DALYs) averted. Costs were assessed in 2009 United States Dollars (US$). To the extent available, analyses were based on locally obtained data. In Costa Rica, the current strategy of treating breast cancer in stages I to IV at a 80% coverage level seems to be the most cost-effective with an incremental cost-effectiveness ratio (ICER) of US$4,739 per DALY averted. At a coverage level of 95%, biennial clinical breast examination (CBE) screening could improve Costa Rica's population health twofold, and can still be considered very cost-effective (ICER US$5,964/DALY). For Mexico, our results indicate that at 95% coverage a mass-media awareness raising program (MAR) could be the most cost-effective (ICER US$5,021/DALY). If more resources are available in Mexico, biennial mammography screening for women 50-70 yrs (ICER US$12,718/DALY), adding trastuzumab (ICER US$13,994/DALY) or screening women 40-70 yrs biennially plus trastuzumab (ICER US$17,115/DALY) are less cost-effective options. We recommend both Costa Rica and Mexico to engage in MAR, CBE or mammography screening programs, depending on their budget. The results of this study should be interpreted with caution however, as the evidence on the intervention effectiveness is uncertain. Also, these programs require several organizational, budgetary and human resources, and the accessibility of breast cancer diagnostic, referral, treatment and palliative care facilities should be improved simultaneously. A gradual implementation of early detection programs should give the respective Ministries of Health the time to negotiate the required budget, train the required human resources and understand possible

  1. Identifying cost-effective CO{sub 2} control levels for amine-based CO{sub 2} capture systems

    SciTech Connect

    Rao, A.B.; Rubin, E.S.

    2006-04-12

    Studies of CO{sub 2} capture and storage (CCS) from coal-fired power plants typically assume a capture efficiency near 90%, although the basis for a particular choice usually is not discussed. Nor do studies systematically explore a range of CO{sub 2} capture efficiencies to identify the most cost-effective levels of CO, control and the key factors that affect such levels. An exploration of these issues is the focus of this paper. As part of the United States Department of Energy's Carbon Sequestration Program, we have developed an integrated modeling framework (called IECM-cs) to evaluate the performance and cost of alternative CCS technologies and power systems in the context of plant-level multipollutant control requirements. This paper uses IECM-cs to identify the most cost-effective level of CO, control using currently available amine-based CO{sub 2} capture technology for PC plants. Two general cases are of interest. First, we examine the effects of systematically increasing the CO{sub 2} capture efficiency of an amine-based system for PC applications over a broad range. We report two measures of cost: (i) capital cost and (ii) cost-effectiveness (cost per tonne of CO{sub 2} avoided) relative to similar plants without CCS. Second, we examine the cost-effectiveness of plant designs that partially bypass the amine capture unit so as to achieve low to moderate reductions of CO{sub 2}, but at lower overall cost. Results from these cases are compared to the conventional case of a capture unit treating the entire flue gas stream. In each case, we identify the most cost-effective strategies and the key factors that affect those results.

  2. Digitally controlled distributed phase shifter

    SciTech Connect

    Hietala, V.M.; Kravitz, S.H.; Vawter, G.A.

    1992-12-31

    A digitally controlled distributed phase shifter is comprised of N phase shifters. Digital control is achieved by using N binary length-weighted electrodes located on the top surface of a waveguide. A control terminal is attached to each electrode thereby allowing the application of a control signal. The control signal is either one of two discrete bias voltages. The application of the discrete bias voltages change the modal index of a portion of the waveguide that corresponds to a length of the electrode to which the bias voltage is applied, thereby causing the phase to change through the underlying portion of the waveguide. The digitally controlled distributed phase shift network has a total phase shift comprised of the sum of the individual phase shifters.

  3. A cost-effective, case-control study on the association between breast cancer and pregnancy through web mining

    PubMed Central

    Yoon, Hong-Jun; Xu, Songhua; Tourassi, Georgia

    2014-01-01

    We report a case-control, breast cancer epidemiological study through mining people stories from the Internet. The aim of the study is to test whether mining openly available, personal stories from the Internet can be a cost-effective way for reliable epidemiological discoveries. As a case study, we focus on the association between breast cancer risk and pregnancy, which is clearly established through controlled clinical survey studies. Specifically, we mined 30,000 online obituary articles. Replicating a case-control study design, our web mining based approach confirmed the general trends reported by traditional epidemiological studies. Our web mining study demonstrates promising preliminary evidence that online content mining can be a cost-effective way for epidemiological knowledge discovery. PMID:25506080

  4. Cost effectiveness of group follow-up after structured education for type 1 diabetes: a cluster randomised controlled trial

    PubMed Central

    2014-01-01

    Background This study examines the cost effectiveness of group follow-up after participation in the Dose Adjustment for Normal Eating (DAFNE) structured education programme for type 1 diabetes. Methods Economic evaluation conducted alongside a cluster randomised controlled trial involving 437 adults with type 1 diabetes in Ireland. Group follow-up involved two group education ‘booster’ sessions post-DAFNE. Individual follow-up involved two standard one-to-one hospital clinic visits. Incremental costs, quality-adjusted life years (QALYs) gained and cost effectiveness were estimated at 18 months. Uncertainty was explored using sensitivity analysis and by estimating cost effectiveness acceptability curves. Results Group follow-up was associated with a mean reduction in QALYs gained of 0.04 per patient (P value, 0.052; 95% CI, −0.08 to 0.01, intra-class correlation (ICC), 0.033) and a mean reduction in total healthcare costs of €772 (P value, 0.020; 95% CI, −1,415 to −128: ICC, 0.016) per patient. At alternative threshold values of €5,000, €15,000, €25,000, €35,000, and €45,000, the probability of group follow-up being cost effective was estimated to be 1.000, 0.762, 0.204, 0.078, and 0.033 respectively. Conclusions The results do not support implementation of group follow-up as the sole means of follow-up post-DAFNE. Given the reported cost savings, future studies should explore the cost effectiveness of alternative models of group care for diabetes. Trial registration Current Controlled Trials ISRCTN79759174 (assigned: 9 February 2007). PMID:24927851

  5. Cost-effectiveness of adherence therapy versus health education for people with schizophrenia: randomised controlled trial in four European countries

    PubMed Central

    2013-01-01

    Background Non-adherence to anti-psychotics is common, expensive and affects recovery. We therefore examine the cost-effectiveness of adherence therapy for people with schizophrenia by multi-centre randomised trial in Amsterdam, London, Leipzig and Verona. Methods Participants received 8 sessions of adherence therapy or health education. We measured lost productivity and use of health/social care, criminal justice system and informal care at baseline and one year to estimate and compare mean total costs from health/social care and societal perspectives. Outcomes were the Short Form 36 (SF-36) mental component score (MCS) and quality-adjusted life years (QALYs) gained (SF-36 and EuroQoL 5 dimension (EQ5D)). Cost-effectiveness was examined for all cost and outcome combinations using cost-effectiveness acceptability curves (CEACs). Results 409 participants were recruited. There were no cost or outcome differences between adherence therapy and health education. The probability of adherence therapy being cost-effective compared to health education was between 0.3 and 0.6 for the six cost-outcome combinations at the willingness to pay thresholds we examined. Conclusions Adherence therapy appears equivalent to health education. It is unclear whether it would have performed differently against a treatment as usual control, whether such an intervention can impact on quality of life in the short-term, or whether it is likely to be cost-effective in some sites but not others. Trial registration Trial registration: Current Controlled Trials ISRCTN01816159 PMID:23705862

  6. All digital pulsewidth control loop

    NASA Astrophysics Data System (ADS)

    Huang, Hong-Yi; Jan, Shiun-Dian; Pu, Ruei-Iun

    2013-03-01

    This work presents an all-digital pulsewidth control loop (ADPWCL). The proposed system accepts a wide range of input duty cycles and performs a fast correction to the target output pulsewidth. An all-digital delay-locked loop (DLL) with fast locking time using a simplified time to digital converter and a new differential two-step delay element is proposed. The area of the delay element is much smaller than that in conventional designs, while having the same delay range. A test chip is verified in a 0.18-µm CMOS process. The measured duty cycle ranges from 4% to 98% with 7-bit resolution.

  7. Cost-effectiveness of malaria microscopy and rapid diagnostic tests versus presumptive diagnosis: implications for malaria control in Uganda

    PubMed Central

    2011-01-01

    Background Current Uganda National Malaria treatment guidelines recommend parasitological confirmation either by microscopy or rapid diagnostic test (RDT) before treatment with artemether-lumefantrine (AL). However, the cost-effectiveness of these strategies has not been assessed at rural operational primary care centres. Methods Three health centres (HCs) were randomized to three diagnostic arms (microscopy, RDT and presumptive diagnosis) in a district of low and another of high malaria transmission intensities in Uganda. Some 22,052 patients presenting with fever at outpatients departments were enrolled from March 2010 to February 2011. Of these, a random sample of 1,627 was selected to measure additional socio-economic characteristics. Costing was performed following the standard step-down cost allocation and the ingredients approach. Effectiveness was measured as the number and proportion of patients correctly diagnosed and treated. Incremental Cost-Effectiveness Ratios (ICERs) were estimated from the societal perspective (http://Clinicaltrials.gov, NCT00565071). Results Overall RDT was most cost-effective with lowest ICER US$5.0 compared to microscopy US$9.61 per case correctly diagnosed and treated. In the high transmission setting, ICER was US$4.38 for RDT and US$12.98 for microscopy. The corresponding ICERs in the low transmission setting were US$5.85 and US$7.63 respectively. The difference in ICERs between RDT and microscopy was greater in the high transmission area (US$8.9) than in low transmission setting (US$1.78). At a willingness to pay of US$2.8, RDT remained cost effective up to a threshold value of the cost of treatment of US$4.7. Conclusion RDT was cost effective in both low and high transmission settings. With a global campaign to reduce the costs of AL and RDT, the Malaria Control Programme and stakeholders need a strategy for malaria diagnosis because as the cost of AL decreases, presumptive treatment is likely to become more attractive. PMID

  8. A Cost-Effective Mindfulness Stress Reduction Program: A Randomized Control Trial for Breast Cancer Survivors.

    PubMed

    Lengacher, Cecile A; Kip, Kevin E; Reich, Richard R; Craig, Benjamin M; Mogos, Mulubrhan; Ramesar, Sophia; Paterson, Carly L; Farias, Jerrica R; Pracht, Etienne

    2015-01-01

    Many breast cancer survivors continue to experience residual symptoms including anxiety, cognitive impairment, depression, fatigue, and pain. In this study, the cost-effectiveness of a Mindfulness-Based Stress Reduction intervention for breast cancer survivors was examined. The cost of the program was assessed from the societal perspective, accounting for both direct medical and patient opportunity costs. The cost per quality-adjusted life year was relatively low compared to the cost-utility findings of other published breast cancer interventions. The program appears to provide for significantly improved health-related quality of life at a comparativelv low cost. PMID:26477119

  9. Cost-effectiveness of physical activity among women with menopause symptoms: findings from a randomised controlled trial.

    PubMed

    Kolu, Päivi; Raitanen, Jani; Nygård, Clas-Håkan; Tomás, Eija; Luoto, Riitta

    2015-01-01

    Menopause is a period that may predispose one to a decrease in muscle strength, cardiorespiratory fitness, and quality of life. A study was carried out to evaluate the cost-effectiveness of physical activity among women displaying symptoms of menopause. The cost-effectiveness analysis was based on data from a six-month randomised controlled trial (n = 151). The women in the intervention group engaged in an unsupervised session of at least 50 minutes of physical activity four times a week. The control group continued their physical activity as before. An incremental cost-effectiveness ratio (ICER) was calculated in terms of maximal oxygen consumption, lean muscle mass, and quality-adjusted life years (QALYs) gained. A bootstrap technique was utilised to estimate uncertainty around the point estimate for ICER associated with the intervention. The mean total cost in the intervention group was €1,307 (SEM: €311) and in the control group was €1,253 (SEM: €279, p = 0.10) per person. The mean intervention cost was €208 per person. After six months of the behaviour-change intervention, the ICER was €63 for a 1 ml/kg/min improvement in cardiorespiratory fitness, the additional cost per one-gram increase in lean muscle mass was €126, and the cost per QALY gained was €46. According to the findings, physical activity among menopausal women was cost-effective for cardiorespiratory fitness, for lean muscle mass, and for QALYs gained, since the intervention was more effective than the actions within the control group and the additional effects of physical activity were gained at a very low price. From the societal perspective, the intervention used may promote ability to work and thereby save on further costs associated with early retirement or disability pension if the physical-activity level remains at least the same as during the intervention. PMID:26258804

  10. A telerobotic digital controller system

    NASA Technical Reports Server (NTRS)

    Brown, Richard J.

    1992-01-01

    This system is a network of joint mounted dual axes digital servo-controllers (DDSC), providing control of various joints and end effectors of different robotic systems. This report provides description of and user required information for the Digital Controller System Network (DSCN) and, in particular, the DDSC, Model DDSC-2, developed to perform the controller functions. The DDSC can control 3 phase brushless or brush type DC motors, requiring up to 8 amps. Only four wires, two for power and 2 for serial communication, are required, except for local sensor and motor connections. This highly capable, very flexible, programmable servo-controller, contained on a single, compact printed circuit board measuring only 4.5 x 5.1 inches, is applicable to control systems of all types from sub-arc second precision pointing to control of robotic joints and end effectors. This document concentrates on the robotic applications for the DDSC.

  11. Digital Controller For Acoustic Levitation

    NASA Technical Reports Server (NTRS)

    Tarver, D. Kent

    1989-01-01

    Acoustic driver digitally controls sound fields along three axes. Allows computerized acoustic levitation and manipulation of small objects for such purposes as containerless processing and nuclear-fusion power experiments. Also used for controlling motion of vibration-testing tables in three dimensions.

  12. Cost-effectiveness of trachoma control measures: comparing targeted household treatment and mass treatment of children.

    PubMed Central

    Frick, K. D.; Lietman, T. M.; Holm, S. O.; Jha, H. C.; Chaudhary, J. S.; Bhatta, R. C.

    2001-01-01

    OBJECTIVE: The present study compares the cost-effectiveness of targeted household treatment and mass treatment of children in the most westerly part of Nepal. METHODS: Effectiveness was measured as the percentage point change in the prevalence of trachoma. Resource measures included personnel time required for treatment, transportation, the time that study subjects had to wait to receive treatment, and the quantity of azithromycin used. The costs of the programme were calculated from the perspectives of the public health programme sponsor, the study subjects, and the society as a whole. FINDINGS: Previous studies have indicated no statistically significant differences in effectiveness, and the present work showed no significant differences in total personnel and transportation costs per child aged 1-10 years, the total time that adults spent waiting, or the quantity of azithromycin per child. However, the mass treatment of children was slightly more effective and used less of each resource per child aged 1-10 years than the targeted treatment of households. CONCLUSION: From all perspectives, the mass treatment of children is at least as effective and no more expensive than targeted household treatment, notwithstanding the absence of statistically significant differences. Less expensive targeting methods are required in order to make targeted household treatment more cost-effective. PMID:11285663

  13. Cost-effectiveness Analysis of Hospital Infection Control Response to an Epidemic Respiratory Virus Threat

    PubMed Central

    Dan, Yock Young; Sim, Joe; Lim, Jeremy; Hsu, Li Yang; Chow, Wai Leng; Fisher, Dale A.; Wong, Yue Sie; Ho, Khek Yu

    2009-01-01

    The outbreak of influenza A pandemic (H1N1) 2009 prompted many countries in Asia, previously strongly affected by severe acute respiratory syndrome (SARS), to respond with stringent measures, particularly in preventing outbreaks in hospitals. We studied actual direct costs and cost-effectiveness of different response measures from a hospital perspective in tertiary hospitals in Singapore by simulating outbreaks of SARS, pandemic (H1N1) 2009, and 1918 Spanish influenza. Protection measures targeting only infected patients yielded lowest incremental cost/death averted of $23,000 (US$) for pandemic (H1N1) 2009. Enforced protection in high-risk areas (Yellow Alert) and full protection throughout the hospital (Orange Alert) averted deaths but came at an incremental cost of up to $2.5 million/death averted. SARS and Spanish influenza favored more stringent measures. High case-fatality rates, virulence, and high proportion of atypical manifestations impacted cost-effectiveness the most. A calibrated approach in accordance with viral characteristics and community risks may help refine responses to future epidemics. PMID:19961669

  14. Cost-effectiveness of telehealth for patients with raised cardiovascular disease risk: evidence from the Healthlines randomised controlled trial

    PubMed Central

    Dixon, Padraig; Edwards, Louisa; Thomas, Clare; Gaunt, Daisy; Foster, Alexis; Large, Shirley; Montgomery, Alan A

    2016-01-01

    Objectives To investigate the cost-effectiveness of a telehealth intervention for primary care patients with raised cardiovascular disease (CVD) risk. Design A prospective within-trial patient-level economic evaluation conducted alongside a randomised controlled trial. Setting Patients recruited through primary care, and intervention delivered via telehealth service. Participants Adults with a 10-year CVD risk ≥20%, as measured by the QRISK2 algorithm, with at least 1 modifiable risk factor. Intervention A series of up to 13 scripted, theory-led telehealth encounters with healthcare advisors, who supported participants to make behaviour change, use online resources, optimise medication and improve adherence. Participants in the control arm received usual care. Primary and secondary outcome measures Cost-effectiveness measured by net monetary benefit at the end of 12 months of follow-up, calculated from incremental cost and incremental quality-adjusted life years (QALYs). Productivity impacts, participant out-of-pocket expenditure and the clinical outcome were presented in a cost-consequences framework. Results 641 participants were randomised—325 to receive the telehealth intervention in addition to usual care and 316 to receive only usual care. 18% of participants had missing data on either costs, utilities or both. Multiple imputation was used for the base case results. The intervention was associated with incremental mean per-patient National Health Service (NHS) costs of £138 (95% CI 66 to 211) and an incremental QALY gain of 0.012 (95% CI −0.001 to 0.026). The incremental cost-effectiveness ratio was £10 859. Net monetary benefit at a cost-effectiveness threshold of £20 000 per QALY was £116 (95% CI −58 to 291), and the probability that the intervention was cost-effective at this threshold value was 0.77. Similar results were obtained from a complete case analysis. Conclusions There is evidence to suggest that the Healthlines telehealth

  15. Aircraft digital control design methods

    NASA Technical Reports Server (NTRS)

    Tashker, M. G.; Powell, J. D.

    1975-01-01

    Investigations were conducted in two main areas: the first area is control system design, and the goals were to define the limits of 'digitized S-Plane design techniques' vs. sample rate, to show the results of a 'direct digital design technique', and to compare the two methods; the second area was to evaluate the roughness of autopilot designs parametrically versus sample rate. Goals of the first area were addressed by (1) an analysis of a 2nd order example using both design methods, (2) a linear analysis of the complete 737 aircraft with an autoland obtained using the digitized S-plane technique, (3) linear analysis of a high frequency 737 approximation with the autoland from a direct digital design technique, and (4) development of a simulation for evaluation of the autopilots with disturbances and nonlinearities included. Roughness evaluation was studied by defining an experiment to be carried out on the Langley motion simulator and coordinated with analysis at Stanford.

  16. [Transmission dynamics and cost-effectiveness of rabies control in dogs and humans in an African city].

    PubMed

    Zinsstag, J; Dürr, S; Penny, M A; Mindekem, R; Roth, F; Menendez Gonzalez, S; Naissengar, S; Hattendorf, J

    2011-12-01

    Control of human rabies in developing countries depends on prevention in dogs. The purpose of this study was to evaluate the cost-saving potential for the public health sector of intervention to control rabies in animal-host reservoirs. An existing deterministic model was adapted to allow study of dog-to-human rabies transmission. Model parameters were fitted to data from routine weekly reports on the number of rabid dogs and human rabies exposures in N'Djamena, Chad. At the onset of study, the estimated effective reproductive ratio (Re) was 1.01 indicating stable low-level endemic rabies transmission. Simulations were performed to determine what effects mass vaccination and culling of dogs would have on the incidence of human rabies. Findings showed that a mass campaign allowing single parenteral vaccination of at least 70% of the canine population would be sufficient to interrupt transmission of rabies to humans for at least 6 years. The cost-effectiveness of mass dog vaccination was compared to that of "postexposure prophylaxis" (PEP) which would not reduce future human exposure. Results showed that a sustained 5-year PEP program together with a dog-vaccination campaign would be as cost-effective as PEP alone. Beyond a time-frame of 7 years, combining parenteral dog vaccination campaigns with human PEP appeared to be more cost-effective than human PEP alone. PMID:22393628

  17. Development and Design of Cost-Effective, Real-Time Implementable Sediment and Contaminant Release Controls

    SciTech Connect

    Hampson, Steve

    2007-08-01

    Alternative design options for integrated storm water and sediment control systems were developed and evaluated for Outfalls 008, 011 and 015 of the Paducah Gaseous Diffusion Plant. The remedial options were required to be cost effective and implementable in a relatively short timeframe. Additionally, construction activities were to minimize earth disturbance, especially with respect to excavation. The current database for storm water and effluent sediment oncentration was assessed for the three outfalls. It was concluded that there was a significant lack of data and recommendations for monitoring equipment were provided to initiate a comprehensive surface water and sediment data acquisition system. Modeling was completed for current conditions. Peak flow, runoff volume, peak sediment concentration and storm sediment load were modeled for storm events, ranging from 0.5 inches (12.7mm) to 3.0 inches (6.2mm). Predicted peak flows ranged from 2.5 cfs (0.071 m3/s) for Outfall 011 and a 0.5 inches (12.7mm) storm to 210 cfs (5.95 m3/s) for Outfall 008 and a 3.0 inches (76.2mm) storm. Additionally, the 100-yr 24-hr NRCS Type II storm was modeled. Storm sediment loads, for the corresponding outfalls and storm events, ranged from 0.1 to 9.0 tons (8.18 tonnes). Retention ponds were designed and evaluated for each of the three outfalls. The ponds had a dual function; 1) contain the storm runoff volume for smaller storm events and 2) passively treat and discharge runoff that was in excess of the pond’s storage capacity. Stored runoff was transferred to alternative secondary treatment systems. The expected performance of these treatment systems was evaluated. The performance of the outfall ponds was evaluated for storm events ranging from 0.5 inches (12.7mm) to 4.0 inches (101.6mm). Outfall 011 has a watershed of 33.3 acres. Pond 011 (Outfall 011) has the largest storage capacity of the three outfalls, and therefore the highest potential for effective treatment. The predicted

  18. Cost-Effectiveness of Bariatric Surgery for Type 2 Diabetes Mellitus: A Randomized Controlled Trial in China.

    PubMed

    Tang, Qi; Sun, Zhipeng; Zhang, Nengwei; Xu, Guangzhong; Song, Peipei; Xu, Lingzhong; Tang, Wei

    2016-05-01

    To compare the remission of type 2 diabetes mellitus (T2DM) through treatment with laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB), and to analyze the cost-effectiveness of medical treatment, LSG, and LRYGB in T2DM patients (BMI ≥ 28).A 2-group randomized controlled trial was conducted at Diabetes Surgery Centre, Beijing Shijitan Hospital in Beijing, China. Subjects were 80 patients ages 16 to 65 years with a body mass index of 28 kg/m or more and duration of T2DM no more than 15 years. Subjects were randomly assigned (1:1) to undergo either LSG (n = 40) or LRYGB (n = 40) between February 3, 2011 and October 31, 2013. Of those patients, 72 (90%) were available at follow-up at 2 years. These patients included 34 (85%) who underwent LSG and 38 (95%) who underwent LRYGB. This study presents the follow-up data at 2 years, which compared LSG and LRYGB in T2DM patients. Partial remission and complete remission were determined, and weight loss, BMI, changes in abdominal circumference, cholesterol, and triglycerides were measured. The cost-effectiveness of each type of bariatric surgery was analyzed with a Markov simulation model that yielded quality-adjusted life-years (QALYs) and costs.From our analysis results, LSG and LRYGB are both have taken a great effect on the reduction of fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), and bodyweight in patients with T2DM. The cost-effectiveness ratios of medical treatment, LSG, and LRYGB respectively are 1589.02, 1028.97, and 1197.44 dollars per QALY.Our analysis indicates that LSG appear to provide a cost-effective method of T2DM treatment for the patients. PMID:27196454

  19. Digitally controlled sonars

    NASA Technical Reports Server (NTRS)

    Hansen, G. R.

    1983-01-01

    Sonars are usually designed and constructed as stand alone instruments. That is, all elements or subsystems of the sonar are provided: power conditioning, displays, intercommunications, control, receiver, transmitter, and transducer. The sonars which are a part of the Advanced Ocean Test Development Platform (AOTDP) represent a departure from this manner of implementation and are configured more like an instrumentation system. Only the transducer, transmitter, and receiver which are unique to a particular sonar function; Up, Down, Side Scan, exist as separable subsystems. The remaining functions are reserved to the AOTDP and serve all sonars and other instrumentation in a shared manner. The organization and functions of the common AOTDP elements were described and then the interface with the sonars discussed. The techniques for software control of the sonar parameters were explained followed by the details of the realization of the sonar functions and some discussion of the performance of the side scan sonars.

  20. Digitally controlled sonars

    NASA Astrophysics Data System (ADS)

    Hansen, G. R.

    1983-10-01

    Sonars are usually designed and constructed as stand alone instruments. That is, all elements or subsystems of the sonar are provided: power conditioning, displays, intercommunications, control, receiver, transmitter, and transducer. The sonars which are a part of the Advanced Ocean Test Development Platform (AOTDP) represent a departure from this manner of implementation and are configured more like an instrumentation system. Only the transducer, transmitter, and receiver which are unique to a particular sonar function; Up, Down, Side Scan, exist as separable subsystems. The remaining functions are reserved to the AOTDP and serve all sonars and other instrumentation in a shared manner. The organization and functions of the common AOTDP elements were described and then the interface with the sonars discussed. The techniques for software control of the sonar parameters were explained followed by the details of the realization of the sonar functions and some discussion of the performance of the side scan sonars.

  1. Screening, isolation, and decolonisation strategies in the control of meticillin resistant Staphylococcus aureus in intensive care units: cost effectiveness evaluation

    PubMed Central

    Graves, Nicholas; Cookson, Barry D; Barnett, Adrian G; Wilson, Jennie A; Edgeworth, Jonathan D; Batra, Rahul; Cuthbertson, Brian H; Cooper, Ben S

    2011-01-01

    Objective To assess the cost effectiveness of screening, isolation, and decolonisation strategies in the control of meticillin resistant Staphylococcus aureus (MRSA) in intensive care units. Design Economic evaluation based on a dynamic transmission model. Setting England and Wales. Population Theoretical population of patients on an intensive care unit. Main outcome measures Infections, deaths, costs, quality adjusted life years (QALYs), incremental cost effectiveness ratios for alternative strategies, and net monetary benefits. Results All decolonisation strategies improved health outcomes and reduced costs. Although universal decolonisation (regardless of MRSA status) was the most cost effective in the short term, strategies using screening to target MRSA carriers may be preferred owing to the reduced risk of selecting for resistance. Among such targeted strategies, universal admission and weekly screening with polymerase chain reaction coupled with decolonisation using nasal mupirocin was the most cost effective. This finding was robust to the size of intensive care units, prevalence of MRSA on admission, proportion of patients classified as high risk, and precise value of willingness to pay for health benefits. All strategies using isolation but not decolonisation improved health outcomes but costs were increased. When the prevalence of MRSA on admission to the intensive care unit was 5% and the willingness to pay per QALY gained was between £20 000 (€23 000; $32 000) and £30 000, the best such strategy was to isolate only those patients at high risk of carrying MRSA (either pre-emptively or after identification by admission and weekly screening for MRSA using chromogenic agar). Universal admission and weekly screening using polymerase chain reaction based detection of MRSA coupled with isolation was unlikely to be cost effective unless prevalence was high (10% of patients colonised with MRSA on admission). Conclusions MRSA control strategies that

  2. Self management, joint protection and exercises in hand osteoarthritis: a randomised controlled trial with cost effectiveness analyses

    PubMed Central

    2011-01-01

    Background There is limited evidence for the clinical and cost effectiveness of occupational therapy (OT) approaches in the management of hand osteoarthritis (OA). Joint protection and hand exercises have been proposed by European guidelines, however the clinical and cost effectiveness of each intervention is unknown. This multicentre two-by-two factorial randomised controlled trial aims to address the following questions: • Is joint protection delivered by an OT more effective in reducing hand pain and disability than no joint protection in people with hand OA in primary care? • Are hand exercises delivered by an OT more effective in reducing hand pain and disability than no hand exercises in people with hand OA in primary care? • Which of the four management approaches explored within the study (leaflet and advice, joint protection, hand exercise, or joint protection and hand exercise combined) provides the most cost-effective use of health care resources Methods/Design Participants aged 50 years and over registered at three general practices in North Staffordshire and Cheshire will be mailed a health survey questionnaire (estimated mailing sample n = 9,500). Those fulfilling the eligibility criteria on the health survey questionnaire will be invited to attend a clinical assessment to assess for the presence of hand or thumb base OA using the ACR criteria. Eligible participants will be randomised to one of four groups: leaflet and advice; joint protection (looking after your joints); hand exercises; or joint protection and hand exercises combined (estimated n = 252). The primary outcome measure will be the OARSI/OMERACT responder criteria combining hand pain and disability (measured using the AUSCAN) and global improvement, 6 months post-randomisation. Secondary outcomes will also be collected for example pain, functional limitation and quality of life. Outcomes will be collected at baseline and 3, 6 and 12 months post-randomisation. The main analysis will

  3. Cost-effectiveness of routine immunization to control Japanese encephalitis in Shanghai, China.

    PubMed Central

    Ding, Ding; Kilgore, Paul E.; Clemens, John D.; Wei, Liu; Zhi-Yi, Xu

    2003-01-01

    OBJECTIVE: To assess the cost-effectiveness of inactivated and live attenuated Japanese encephalitis (JE) vaccines given to infants and children in Shanghai. METHODS: A decision-analytical model was constructed in order to compare costs and outcomes for three hypothetical cohorts of 100,000 children followed from birth in 1997 to the age of 30 years who received either no JE vaccine, inactivated JE vaccine (P3), or live attenuated JE vaccine (SA 14-14-2). Cumulative incidences of JE from birth to 30 years of age in the pre-immunization era, i.e. before 1968, were used to estimate expected rates of JE in the absence of vaccination. The economic consequences were measured as cost per case, per death, and per disability-adjusted life year (DALY) averted for the two JE immunization programmes. FINDINGS: In comparison with no JE immunization, a programme using the P3 vaccine would prevent 420 JE cases and 105 JE deaths and would save 6456 DALYs per 100,000 persons; the use of the SA 14-14-2 vaccine would prevent 427 cases and 107 deaths and would save 6556 DALYs per 100,000 persons. Both kinds of immunization were cost saving but the SA 14-14-2 vaccine strategy resulted in a saving that was 47% greater (512,456 US dollars) than that obtained with the P3 vaccine strategy (348,246 US dollars). CONCLUSION: Both JE immunization strategies resulted in cost savings in comparison with no JE immunization. This provides a strong economic rationale for vaccinating against JE in Shanghai and suggests that vaccination against JE might be economically justifiable in other parts of China and in certain other developing countries of Asia where the disease is endemic. PMID:12856051

  4. Cost Effective Prototyping

    NASA Technical Reports Server (NTRS)

    Wickman, Jerry L.; Kundu, Nikhil K.

    1996-01-01

    This laboratory exercise seeks to develop a cost effective prototype development. The exercise has the potential of linking part design, CAD, mold development, quality control, metrology, mold flow, materials testing, fixture design, automation, limited parts production and other issues as related to plastics manufacturing.

  5. The B-747 flight control system maintenance and reliability data base for cost effectiveness tradeoff studies

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Primary and automatic flight controls are combined for a total flight control reliability and maintenance cost data base using information from two previous reports and additional cost data gathered from a major airline. A comparison of the current B-747 flight control system effects on reliability and operating cost with that of a B-747 designed for an active control wing load alleviation system is provided.

  6. The Cost-Effectiveness of Low-Cost Essential Antihypertensive Medicines for Hypertension Control in China: A Modelling Study

    PubMed Central

    Gu, Dongfeng; He, Jiang; Coxson, Pamela G.; Rasmussen, Petra W.; Huang, Chen; Thanataveerat, Anusorn; Tzong, Keane Y.; Xiong, Juyang; Wang, Miao; Zhao, Dong; Goldman, Lee; Moran, Andrew E.

    2015-01-01

    Background 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. Methods and Findings 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

  7. Digital electronic engine control history

    NASA Technical Reports Server (NTRS)

    Putnam, T. W.

    1984-01-01

    Full authority digital electronic engine controls (DEECs) were studied, developed, and ground tested because of projected benefits in operability, improved performance, reduced maintenance, improved reliability, and lower life cycle costs. The issues of operability and improved performance, however, are assessed in a flight test program. The DEEC on a F100 engine in an F-15 aircraft was demonstrated and evaluated. The events leading to the flight test program are chronicled and important management and technical results are identified.

  8. Cost-Effectiveness of a Biodegradable Compared to a Titanium Fixation System in Maxillofacial Surgery: A Multicenter Randomized Controlled Trial

    PubMed Central

    van Bakelen, N. B.; Vermeulen, K. M.; Buijs, G. J.; Jansma, J.; de Visscher, J. G. A. M.; Hoppenreijs, Th. J. M.; Bergsma, J. E.; Stegenga, B.; Bos, R. R. M.

    2015-01-01

    Background Biodegradable fixation systems could reduce/delete the problems associated with titanium plate removal. This means less surgical discomfort, and a reduction in costs. Aim The aim of the present study was to compare the cost-effectiveness between a biodegradable and a titanium system in Maxillofacial surgery. Materials and Methods This multicenter RCT was performed in the Netherlands from December 2006 to July 2009. Included were 230 patients who underwent a bilateral sagittal split osteotomy (BSSO), a Le Fort-I osteotomy, or a bi-maxillary osteotomy and those treated for fractures of the mandible, maxilla, or zygoma. The patients were randomly assigned to a titanium group (KLS Martin) or to a biodegradable group (Inion CPS). Costs were assessed from a societal perspective. Health outcomes in the incremental cost-effectiveness ratio (ICER) were bone healing (8 weeks) and plate removal (2 years). Results In 25 out of the 117 patients who were randomized to the biodegradable group, the maxillofacial surgeon made the decision to switch to the titanium system intra-operatively. This resulted in an Intention-To-Treat (ITT-)analysis and a Treatment-Received (TR-) analysis. Both analyses indicated that operations performed with titanium plates and screws had better health outcomes. In the TR-analysis the costs were lower in the biodegradable group, in the ITT-analysis costs were lower in the titanium group. Conclusion and Discussion The difference in costs between the ITT and the TR analyses can be explained by the intra-operative switches: In the TR-analysis the switches were analysed in the titanium group. In the ITT-analysis they were analysed in the biodegradable group. Considering the cost-effectiveness the titanium system is preferable to the biodegradable system in the regular treatment spectrum of mandibular, Le Fort-I, and zygomatic fractures, and BSSO’s, Le Fort-I osteotomies and bimaxillary osteotomies. Trial Registration Controlled

  9. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman; Sarah R. Nuss-Warren

    2007-02-01

    The objective of this project is to identify, develop, test, and commercialize emissions control and monitoring technologies that can be implemented by exploration and production (E&P) operators to significantly lower the cost of environmental compliance and expedite project permitting. The project team takes considerable advantage of the emissions control research and development efforts and practices that have been underway in the gas pipeline industry for the last 12 years. These efforts and practices are expected to closely interface with the E&P industry to develop cost-effective options that apply to widely-used field and gathering engines, and which can be readily commercialized. The project is separated into two phases. Phase 1 work establishes an E&P industry liaison group, develops a frequency distribution of installed E&P field engines, and identifies and assesses commercially available and emerging engine emissions control and monitoring technologies. Current and expected E&P engine emissions and monitoring requirements are reviewed, and priority technologies are identified for further development. The identified promising technologies are tested on a laboratory engine to confirm their generic viability. In addition, a full-scale field test of prototype emissions controls will be conducted on at least ten representative field engine models with challenging emissions profiles. Emissions monitoring systems that are integrated with existing controls packages will be developed. Technology transfer/commercialization is expected to be implemented through compressor fleet leasing operators, engine component suppliers, the industry liaison group, and the Petroleum Technology Transfer Council. This topical report discusses work completed during Phase 1 of the project Cost Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines. In this report information, data, and results are compiled and summarized from quarterly

  10. Evaluation of active control technology for short haul aircraft. [cost effectiveness

    NASA Technical Reports Server (NTRS)

    Renshaw, J. H.; Bennett, J. A.; Harris, O. C.; Honrath, J. F.; Patterson, R. W.

    1975-01-01

    An evaluation of the economics of short-haul aircraft designed with active controls technology and low wing-loading to achieve short field performance with good ride quality is presented. Results indicate that for such a system incorporating gust load alleviation and augmented stability the direct operating cost is better than for aircraft without active controls.

  11. Cost-Effective Control Systems for Colleges and Universities: A New Paradigm.

    ERIC Educational Resources Information Center

    Hubbell, Loren Loomis; Dougherty, Jennifer Dowling

    This report addresses the issue of maintaining adequate controls within a streamlined or restructured financial affairs environment at an institution of higher education. It presents a new paradigm for control structures designed to more effectively meet administrators' needs--both in terms of cost and risk management. The first section: (1)…

  12. A Control Framework for Digital Forensics

    NASA Astrophysics Data System (ADS)

    von Solms, Sebastiaan; Louwrens, Cecil; Reekie, Colette; Grobler, Talania

    This paper introduces a control framework for digital forensics. It proposes a taxonomy for control objectives, categorized within the phases of the digital forensic process: planning and preparation, incident response, investigation and juridical/evidentiary. Using the taxonomy as a basis, a digital forensic reference framework, consisting of control groupings, control objectives and detailed control objectives, is defined. The control framework is intended to provide a sound theoretical basis for digital forensics as well as a reference framework for digital forensics governance within organizations.

  13. Cost effective malaria risk control using remote sensing and environmental data

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Z.; Roytman, Leonid; Kadik, Abdel Hamid

    2012-06-01

    Malaria transmission in many part of the world specifically in Bangladesh and southern African countries is unstable and epidemic. An estimate of over a million cases is reported annually. Malaria is heterogeneous, potentially due to variations in ecological settings, socio-economic status, land cover, and agricultural practices. Malaria control only relies on treatment and supply of bed networks. Drug resistance to these diseases is widespread. Vector control is minimal. Malaria control in those countries faces many formidable challenges such as inadequate accessibility to effective treatment, lack of trained manpower, inaccessibility of endemic areas, poverty, lack of education, poor health infrastructure and low health budgets. Health facilities for malaria management are limited, surveillance is inadequate, and vector control is insufficient. Control can only be successful if the right methods are used at the right time in the right place. This paper aims to improve malaria control by developing malaria risk maps and risk models using satellite remote sensing data by identifying, assessing, and mapping determinants of malaria associated with environmental, socio-economic, malaria control, and agricultural factors.

  14. Centralized digital control of accelerators

    SciTech Connect

    Melen, R.E.

    1983-09-01

    In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors.

  15. Fundamentals of direct digital control

    SciTech Connect

    Zimmerman, A.J.

    1996-05-01

    The 14th Century British philosopher William of Occam introduced the principle known today as Occam`s Razor, which can be paraphrased as: The right answer to a given problem requires only the minimum assumptions necessary to explain it adequately. In this article the author uses Occam`s Razor to carve away the excess rhetoric and verbiage surrounding direct digital control (DDC). It is often surprising just how simple in principle a DDC system can be while producing sophisticated performance. This article will examine the basic components and functions common to most DDC systems for commercial building HVAC control, from the point of view of specifier, owner, and operator.

  16. Digital Controller For Emergency Beacon

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.

    1990-01-01

    Prototype digital controller intended for use in 406-MHz emergency beacon. Undergoing development according to international specifications, 406-MHz emergency beacon system includes satellites providing worldwide monitoring of beacons, with Doppler tracking to locate each beacon within 5 km. Controller turns beacon on and off and generates binary codes identifying source (e.g., ship, aircraft, person, or vehicle on land). Codes transmitted by phase modulation. Knowing code, monitor attempts to communicate with user, monitor uses code information to dispatch rescue team appropriate to type and locations of carrier.

  17. Digital electrospray for controlled deposition.

    PubMed

    Deng, Weiwei; Waits, C Mike; Gomez, Alessandro

    2010-03-01

    Many novel functional structures are now fabricated by controlled deposition as a maskless, bottom-up fabrication technique. These applications require rapid and precise deposition of minute amounts of solutions/suspensions or their ultimate particle products in predefined patterns. The electrospray is a promising alternative to the commonly used inkjet printing because it can easily handle highly viscous liquid, avoid high shear rates, and has low risk of clogging. We demonstrate a proof-of-concept digital electrospray. This system consists of a 61-nozzle array microfabricated in silicon and a 61-element digital extractor fabricated using flexible polyimide substrates. "Digital" refers to the state of each electrospray source that can be tuned either on or off independently and responsively. We showed a resolution of 675 mum and a response frequency up to 100 Hz. With similar design and industry standard fabrication procedures, it is feasible to scale up the system to O(1000) sources with spatial resolution better than 250 mum and a O(kHz) response frequency. The latter is controlled by the viscous damping time. PMID:20370220

  18. Current status of mosquito control programs in North Carolina: the need for cost-effectiveness analysis.

    PubMed

    Del Rosario, Katie L; Richards, Stephanie L; Anderson, Alice L; Balanay, Jo Anne G

    2014-04-01

    Mosquito control in the U.S. is both technically specialized and labor intensive with mosquito control programs (MCPs) carrying out services at federal, state, and local levels. The scope of each MCP varies depending on the needs of the region. In the 1970s, the North Carolina Department of Environment and Natural Resources formed the Public Health Pest Management (PHPM) section to play an active leadership role in training and support for local mosquito control programs across the state. PHPM was disbanded, however, in July 2011 due to state budget cuts. The extent to which recent budget shortfalls have impacted services provided by MCPs is largely unknown. Consequently, the primary objectives of the study described in this article were to 1) assess the current status of MCPs in North Carolina, 2) evaluate the extent to which the operational status of local MCPs affects public health, and 3) evaluate the impacts of losing the PHPM section in North Carolina. PMID:24749220

  19. COST EFFECTIVE CONTROL OF HEXAVALENT CHROMIUM AIR EMISSIONS FROM FUNCTIONAL CHROMIUM ELECTROPLATING

    EPA Science Inventory

    This paper will summrize thie pollution prevention (p2) method to control stack emissions from hard chromium plating operations performed by the USEPA's National Risk Management Research Laboratory (NRMRL) over the last four years. During literature research and user surveys, it...

  20. Cost effective development of a Shuttle-based astronomical instrument control system

    NASA Technical Reports Server (NTRS)

    Parise, R. A.; Blum, A.; Budney, T. J.; Stone, R. W.

    1982-01-01

    The high level language FORTH is used for the electronic control of the Space Shuttle-based Ultraviolet Imaging Telescope, in a flight computer system which minimizes costs. The greater part of the breadboard version of the flight computer is assembled from commercially available components, reducing novel circuit design features and permitting simultaneous development of both hardware and software. The commercial boards are then refabricated on aluminum core heat conducting stock, using high reliability parts to produce the flight versions of the system. The system's ground support equipment employs a MINC-25 minicomputer which performs such functions as flight computer software development, PROM programming, test and integration support, and flight operations support. The implementation of these concepts in flight computer telescope controls is described.

  1. Is control through utilization a cost effective Prosopis juliflora management strategy?

    PubMed

    Wakie, Tewodros T; Hoag, Dana; Evangelista, Paul H; Luizza, Matthew; Laituri, Melinda

    2016-03-01

    The invasive tree Prosopis juliflora is known to cause negative impacts on invaded ranges. High P. juliflora eradication costs have swayed developing countries to follow a new and less expensive approach known as control through utilization. However, the net benefits of this new approach have not been thoroughly evaluated. Our objective was to assess the economic feasibility of selected P. juliflora eradication and utilization approaches that are currently practiced in one of the severely affected developing countries, Ethiopia. The selected approaches include converting P. juliflora infested lands into irrigated farms (conversion), charcoal production, and seed flour production. We estimate the costs and revenues of the selected P. juliflora eradication and utilization approaches by interviewing 19 enterprise owners. We assess the economic feasibility of the enterprises by performing enterprise, break-even, investment, sensitivity, and risk analyses. Our results show that conversion to irrigated cotton is economically profitable, with Net Present Value (NPV) of 5234 US$/ha over 10 years and an interest rate of 10% per year. Conversion greatly reduces the spread of P. juliflora on farmlands. Managing P. juliflora infested lands for charcoal production with a four-year harvest cycle is profitable, with NPV of 805 US$/ha. However, the production process needs vigilant regulation to protect native plants from exploitation and caution should be taken to prevent charcoal production sites from becoming potential seed sources. Though flour from P. juliflora pods can reduce invasions by destroying viable seeds, flour enterprises in Ethiopia are unprofitable. Conversion and charcoal production can be undertaken with small investment costs, while flour production requires high investment costs. Introducing new changes in the production and management steps of P. juliflora flour might be considered to make the enterprise profitable. Our study shows that control

  2. Aircraft digital control design methods

    NASA Technical Reports Server (NTRS)

    Powell, J. D.; Parsons, E.; Tashker, M. G.

    1976-01-01

    Variations in design methods for aircraft digital flight control are evaluated and compared. The methods fall into two categories; those where the design is done in the continuous domain (or s plane) and those where the design is done in the discrete domain (or z plane). Design method fidelity is evaluated by examining closed loop root movement and the frequency response of the discretely controlled continuous aircraft. It was found that all methods provided acceptable performance for sample rates greater than 10 cps except the uncompensated s plane design method which was acceptable above 20 cps. A design procedure based on optimal control methods was proposed that provided the best fidelity at very slow sample rates and required no design iterations for changing sample rates.

  3. Cost-effectiveness analysis of tuberculosis control policies in Ivanovo Oblast, Russian Federation. Ivanovo Tuberculosis Project Study Group.

    PubMed

    Migliori, G B; Khomenko, A G; Punga, V V; Ambrosetti, M; Danilova, I; Ribka, L N; Grzemska, M; Sawert, H; Raviglione, M C

    1998-01-01

    Many of the current tuberculosis control programmes in the Russian Federation are based on costly strategies which are underfunded and use long, individualized treatment regimens. This article compares, using a cost-effectiveness analysis, the new WHO strategy implemented in the Ivanovo Oblast (case-finding among symptomatic patients (SCF) and shorter regimens) and the old strategy (active screening of the asymptomatic population (ACF) and longer regimens). The cost per case cured was calculated at different levels of cure rate (45-95%) using three scenarios to describe the new WHO strategy (use of WHO-recommended regimens and three options at increasing rates of admission) and a fourth scenario to describe the old strategy (all patients admitted for the whole treatment and longer regimens). The cost per case detected was determined by calculating the following: yield of the new and old strategy (number of examinations necessary to diagnose one case); cost of the diagnostic process; multiplying yield per cost according to the three scenarios describing the new WHO strategy and a fourth scenario describing the old strategy. In the Ivanovo Oblast the cost per case cured, at 85% cure rate level, ranged from US$ 1197 (new strategy, scenario 1 without food) to US$ 6293 (old strategy, scenario 4) the cost per case detected ranged from US$ 1581 (new strategy, scenario 1) to US$ 4000 (old strategy, scenario 4). Significant savings can result from shifting towards the new WHO strategy. Decision-makers and health administrators should be responsible for re-investing the financial and human resources mobilized by the adoption of cost-effective strategies within the TB control programme. PMID:9868838

  4. Cost-effectiveness of a vocational enablement protocol for employees with hearing impairment; design of a randomized controlled trial

    PubMed Central

    2012-01-01

    Background Hearing impairment at the workplace, and the resulting psychosocial problems are a major health problem with substantial costs for employees, companies, and society. Therefore, it is important to develop interventions to support hearing impaired employees. The objective of this article is to describe the design of a randomized controlled trial evaluating the (cost-) effectiveness of a Vocational Enablement Protocol (VEP) compared with usual care. Methods/Design Participants will be selected with the 'Hearing and Distress Screener'. The study population will consist of 160 hearing impaired employees. The VEP intervention group will be compared with usual care. The VEP integrated care programme consists of a multidisciplinary assessment of auditory function, work demands, and personal characteristics. The goal of the intervention is to facilitate participation in work. The primary outcome measure of the study is 'need for recovery after work'. Secondary outcome measures are coping with hearing impairment, distress, self-efficacy, psychosocial workload, job control, general health status, sick leave, work productivity, and health care use. Outcome measures will be assessed by questionnaires at baseline, and 3, 6, 9, and 12 months after baseline. The economic evaluation will be performed from both a societal and a company perspective. A process evaluation will also be performed. Discussion Interventions addressing occupational difficulties of hearing impaired employees are rare but highly needed. If the VEP integrated care programme proves to be (cost-) effective, the intervention can have an impact on the well-being of hearing impaired employees, and thereby, on the costs for the company as well for the society. Trial registration Netherlands Trial Register (NTR): NTR2782 PMID:22380920

  5. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E & P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman; Sarah R. Nuss-Warren

    2006-09-30

    Continuing work in controlled testing uses a one cylinder Ajax DP-115 (a 13.25 in bore x 16 in stroke, 360 rpm engine) to assess a sequential analysis and evaluation of a series of engine upgrades. As with most of the engines used in the natural gas industry, the Ajax engine is a mature engine with widespread usage throughout the gas gathering industry. The end point is an assessment of these technologies that assigns a cost per unit reduction in NO{sub X} emissions. Technologies including one pre-combustion chamber, in-cylinder sensors, the means to adjust the air-to-fuel ratio, and modification of the air filter housing have been evaluated in previous reports. Current work tests non-production, prototype, mid-pressure fuel valves and begins analysis of these tests. This analysis reveals questions which must be answered before coming to any firm conclusions about the use of the180 psig fuel valve. The research team plans to continue with the remaining pre-combustion chamber tests in the coming quarter. By using the Ajax DP-115 these tests are completed in a low-cost and efficient manner. The various technologies can be quickly exchanged with different hardware, and it is inexpensive to run the engine. Progress in moving toward field testing is discussed, and a change in strategy is suggested. Although field engines are available to test, it is suggested that the final field testing be put on hold due to information from outside publications during this last quarter. Instead, KSU would focus on related field-testing and characterization in an outside project that will close an apparent technology gap. The results of this characterization will give a more solid footing to the field testing that will complete this project.

  6. Cost effective CD control for DUV implant layers using the Archer MPX focus-exposure monitor

    NASA Astrophysics Data System (ADS)

    Hannon, Sean; Eichelberger, Brad; Nelson, Chris; Dinu, Berta; Kennemer, Harold; Monahan, Kevin

    2005-05-01

    CD control is one of the main parameters for IC product performances and a major contributor to yield performance. Traditional SEM metrology can be a challenge on particular layers due to normal process variation and has not proven to provide sufficient focus monitoring ability. This in turn causes false positives resulting in unnecessary rework, but more importantly missed focus excursions resulting in yield loss. Alexander Starikov, Intel Corporation, alludes to the fact that focus and exposure "knobs" account for greater than 80% of CD correctible variance1. Spansion F25 is evaluating an alternative technology using an optical method for the indirect monitoring of the CD on the implant layer. The optical method utilizes a dual tone line-end-shortening (LES) target which is measured on a standard optical overlay tool. The dual tone technology enables the ability to separate the contributions of the focus and exposure resulting in a more accurate characterization of the two parameters on standard production wafers. Ultimately by keeping focus and exposure within acceptable limits it can be assumed that the CD will be within acceptable limits as well without the unnecessary rework caused by process variation. By using designed experiments this paper will provide characterization of the LES technique on the implant layer showing its ability to separate focus-exposure errors vs. the traditional SEM metrology. Actual high volume production data will be used to compare the robustness and sensitivity of the two technologies in a real life production environment. An overall outline of the production implementation will be documented as well.

  7. COST-EFFECTIVE CONTROL OF NOx WITH INTEGRATED ULTRA LOW-NOx BURNERS AND SNCR

    SciTech Connect

    Hamid Farzan; Jennifer Sivy; Alan Sayre; John Boyle

    2003-07-01

    Under sponsorship of the Department of Energy's National Energy Technology Laboratory (NETL), McDermott Technology, Inc. (MTI), the Babcock & Wilcox Company (B&W), and Fuel Tech teamed together to investigate an integrated solution for NOx control. The system was comprised of B&W's DRB-4Z{trademark} low-NO{sub x} pulverized coal (PC) burner technology and Fuel Tech's NO{sub x}OUT{reg_sign}, a urea-based selective non-catalytic reduction (SNCR) technology. The technology's emission target is achieving 0.15 lb NO{sub x}/10{sup 6} Btu for full-scale boilers. Development of the low-NOx burner technology has been a focus in B&W's combustion program. The DRB-4Z{trademark} burner (see Figure 1.1) is B&W's newest low-NO{sub x} burner capable of achieving very low NO{sub x}. The burner is designed to reduce NO{sub x} by diverting air away from the core of the flame, which reduces local stoichiometry during coal devolatilization and, thereby, reduces initial NO{sub x} formation. Figure 1.2 shows the historical NO{sub x} emission levels from different B&W burners. Figure 1.2 shows that based on three large-scale commercial installations of the DRB-4Z{trademark} burners in combination with OFA ports, using Western subbituminous coal, the NO{sub x} emissions ranged from 0.16 to 0.18 lb/10{sup 6} Btu. It appears that with continuing research and development the Ozone Transport Rule (OTR) emission level of 0.15 lb NO{sub x}/10{sup 6} Btu is within the reach of combustion modification techniques for boilers using western U.S. subbituminous coals. Although NO{sub x} emissions from the DRB-4Z{trademark} burner are nearing OTR emission level with subbituminous coals, the utility boiler owners that use bituminous coals can still benefit from the addition of an SNCR and/or SCR system in order to comply with the stringent NO{sub x} emission levels facing them.

  8. Multirate digital control system design

    NASA Technical Reports Server (NTRS)

    Berg, Martin C.; Amit, Naftali; Powell, J. David

    1988-01-01

    Methods for multirate digital control system design are discussed. A simple method for sampling rate selection based on control bandwidths is proposed. Methods for generating a discrete-time state model of a sampled-data plant and a discrete-time equivalent to an analog cost function for a sampled-data plant are described. The succesive loop closures and linear quadratic Gaussian synthesis methods are reviewed, and a constrained optimization synthesis method is introduced. The proposed sampling rate selection, discretization, and synthesis methods are applied to two example design problems. Multirate and single-rate compensators synthesized by the different methods are compared, based on closed-loop responses, with compensators having the same real-time computation load.

  9. Schistosomiais and Soil-Transmitted Helminth Control in Niger: Cost Effectiveness of School Based and Community Distributed Mass Drug Administration

    PubMed Central

    Leslie, Jacqueline; Garba, Amadou; Oliva, Elisa Bosque; Barkire, Arouna; Tinni, Amadou Aboubacar; Djibo, Ali; Mounkaila, Idrissa; Fenwick, Alan

    2011-01-01

    Background In 2004 Niger established a large scale schistosomiasis and soil-transmitted helminths control programme targeting children aged 5–14 years and adults. In two years 4.3 million treatments were delivered in 40 districts using school based and community distribution. Method and Findings Four districts were surveyed in 2006 to estimate the economic cost per district, per treatment and per schistosomiasis infection averted. The study compares the costs of treatment at start up and in a subsequent year, identifies the allocation of costs by activity, input and organisation, and assesses the cost of treatment. The cost of delivery provided by teachers is compared to cost of delivery by community distributers (CDD). The total economic cost of the programme including programmatic, national and local government costs and international support in four study districts, over two years, was US$ 456,718; an economic cost/treatment of $0.58. The full economic delivery cost of school based treatment in 2005/06 was $0.76, and for community distribution was $0.46. Including only the programme costs the figures are $0.47 and $0.41 respectively. Differences at sub-district are more marked. This is partly explained by the fact that a CDD treats 5.8 people for every one treated in school. The range in cost effectiveness for both direct and direct and indirect treatments is quantified and the need to develop and refine such estimates is emphasised. Conclusions The relative cost effectiveness of school and community delivery differs by country according to the composition of the population treated, the numbers targeted and treated at school and in the community, the cost and frequency of training teachers and CDDs. Options analysis of technical and implementation alternatives including a financial analysis should form part of the programme design process. PMID:22022622

  10. Highly integrated digital electronic control: Digital flight control, aircraft model identification, and adaptive engine control

    NASA Technical Reports Server (NTRS)

    Baer-Riedhart, Jennifer L.; Landy, Robert J.

    1987-01-01

    The highly integrated digital electronic control (HIDEC) program at NASA Ames Research Center, Dryden Flight Research Facility is a multiphase flight research program to quantify the benefits of promising integrated control systems. McDonnell Aircraft Company is the prime contractor, with United Technologies Pratt and Whitney Aircraft, and Lear Siegler Incorporated as major subcontractors. The NASA F-15A testbed aircraft was modified by the HIDEC program by installing a digital electronic flight control system (DEFCS) and replacing the standard F100 (Arab 3) engines with F100 engine model derivative (EMD) engines equipped with digital electronic engine controls (DEEC), and integrating the DEEC's and DEFCS. The modified aircraft provides the capability for testing many integrated control modes involving the flight controls, engine controls, and inlet controls. This paper focuses on the first two phases of the HIDEC program, which are the digital flight control system/aircraft model identification (DEFCS/AMI) phase and the adaptive engine control system (ADECS) phase.

  11. Controlling the digital transfer process

    NASA Astrophysics Data System (ADS)

    Brunner, Felix

    1997-02-01

    The accuracy of today's color management systems fails to satisfy the requirements of the graphic arts market. A first explanation for this is that color calibration charts on which these systems rely, because of print technical reasons, are subject to color deviations and inconsistencies. A second reason is that colorimetry describes the human visual perception of color differences and has no direct relation to the rendering technology itself of a proofing or printing device. The author explains that only firm process control of the many parameters in offset printing by means of a system as for example EUROSTANDARD System Brunner, can lead to accurate and consistent calibration of scanner, display, proof and print. The same principles hold for the quality management of digital presses.

  12. Research in digital adaptive flight controllers

    NASA Technical Reports Server (NTRS)

    Kaufman, H.

    1976-01-01

    A design study of adaptive control logic suitable for implementation in modern airborne digital flight computers was conducted. Both explicit controllers which directly utilize parameter identification and implicit controllers which do not require identification were considered. Extensive analytical and simulation efforts resulted in the recommendation of two explicit digital adaptive flight controllers. Interface weighted least squares estimation procedures with control logic were developed using either optimal regulator theory or with control logic based upon single stage performance indices.

  13. Cost Effectiveness of Community Based Strategies for Blood Pressure Control in a Low income Developing Country: Findings from A Cluster Randomized Factorial Controlled Trial

    PubMed Central

    Jafar, Tazeen H; Islam, Muhammad; Bux, Rasool; Poulter, Neil; Hatcher, Juanita; Chaturvedi, Nish; Ebrahim, Shah; Cosgrove, Peter

    2011-01-01

    Background Evidence on economically efficient strategies to lower blood pressure (BP) from low- and middle-income countries remains scarce. The Control of Blood Pressure and Risk Attenuation (COBRA) trial randomized 1341 hypertensive subjects in 12 randomly selected communities in Karachi, Pakistan, to three intervention programs: combined home health education (HHE) plus trained general practitioner (GP); 2) HHE only; 3) trained GP only. The comparator was no intervention (or usual care). The reduction in BP was most pronounced in the combined group. The present study examined the cost-effectiveness of these strategies. Methods and Results Total costs were assessed at baseline and 2 years to estimate incremental cost effectiveness ratios (ICER) based on (a) intervention cost; b) cost of physician consultation, medications and diagnostics, changes in lifestyle, and productivity loss and (c) change in systolic BP. Precision of the ICER estimates was assessed by 1000 bootstrapping replications. Bayesian probabilistic sensitivity analysis was also performed. The annual per participant cost associated with the combined HHE plus trained GP, HHE alone, and trained GP alone were $3.99, $3.34, and $0.65, respectively. HHE plus trained GP was the most cost effective intervention with an ICER of $ 23 (6 to 99) per mm Hg reduction in systolic BP compared to usual care and remained so in 97.7% of 1000 bootstrapped replications. Conclusions The combined intervention of HHE plus trained GP is potentially affordable and more cost effective for BP control than usual care or either strategy alone in some communities in Pakistan, and possibly other countries in Indo-China with similar healthcare infrastructure. PMID:21931077

  14. Cost-Effective Control of Plant Disease When Epidemiological Knowledge Is Incomplete: Modelling Bahia Bark Scaling of Citrus

    PubMed Central

    Neri, Franco M.; DeSimone, R. Erik; Gilligan, Christopher A.

    2014-01-01

    A spatially-explicit, stochastic model is developed for Bahia bark scaling, a threat to citrus production in north-eastern Brazil, and is used to assess epidemiological principles underlying the cost-effectiveness of disease control strategies. The model is fitted via Markov chain Monte Carlo with data augmentation to snapshots of disease spread derived from a previously-reported multi-year experiment. Goodness-of-fit tests strongly supported the fit of the model, even though the detailed etiology of the disease is unknown and was not explicitly included in the model. Key epidemiological parameters including the infection rate, incubation period and scale of dispersal are estimated from the spread data. This allows us to scale-up the experimental results to predict the effect of the level of initial inoculum on disease progression in a typically-sized citrus grove. The efficacies of two cultural control measures are assessed: altering the spacing of host plants, and roguing symptomatic trees. Reducing planting density can slow disease spread significantly if the distance between hosts is sufficiently large. However, low density groves have fewer plants per hectare. The optimum density of productive plants is therefore recovered at an intermediate host spacing. Roguing, even when detection of symptomatic plants is imperfect, can lead to very effective control. However, scouting for disease symptoms incurs a cost. We use the model to balance the cost of scouting against the number of plants lost to disease, and show how to determine a roguing schedule that optimises profit. The trade-offs underlying the two optima we identify—the optimal host spacing and the optimal roguing schedule—are applicable to many pathosystems. Our work demonstrates how a carefully parameterised mathematical model can be used to find these optima. It also illustrates how mathematical models can be used in even this most challenging of situations in which the underlying epidemiology is ill

  15. Cost-effective control of plant disease when epidemiological knowledge is incomplete: modelling Bahia bark scaling of citrus.

    PubMed

    Cunniffe, Nik J; Laranjeira, Francisco F; Neri, Franco M; DeSimone, R Erik; Gilligan, Christopher A

    2014-08-01

    A spatially-explicit, stochastic model is developed for Bahia bark scaling, a threat to citrus production in north-eastern Brazil, and is used to assess epidemiological principles underlying the cost-effectiveness of disease control strategies. The model is fitted via Markov chain Monte Carlo with data augmentation to snapshots of disease spread derived from a previously-reported multi-year experiment. Goodness-of-fit tests strongly supported the fit of the model, even though the detailed etiology of the disease is unknown and was not explicitly included in the model. Key epidemiological parameters including the infection rate, incubation period and scale of dispersal are estimated from the spread data. This allows us to scale-up the experimental results to predict the effect of the level of initial inoculum on disease progression in a typically-sized citrus grove. The efficacies of two cultural control measures are assessed: altering the spacing of host plants, and roguing symptomatic trees. Reducing planting density can slow disease spread significantly if the distance between hosts is sufficiently large. However, low density groves have fewer plants per hectare. The optimum density of productive plants is therefore recovered at an intermediate host spacing. Roguing, even when detection of symptomatic plants is imperfect, can lead to very effective control. However, scouting for disease symptoms incurs a cost. We use the model to balance the cost of scouting against the number of plants lost to disease, and show how to determine a roguing schedule that optimises profit. The trade-offs underlying the two optima we identify-the optimal host spacing and the optimal roguing schedule-are applicable to many pathosystems. Our work demonstrates how a carefully parameterised mathematical model can be used to find these optima. It also illustrates how mathematical models can be used in even this most challenging of situations in which the underlying epidemiology is ill

  16. Cost-Effective Control of Chronic Viral Diseases: Finding the Optimal Level of Screening and Contact Tracing

    PubMed Central

    Armbruster, Benjamin; Brandeau, Margaret L.

    2010-01-01

    Chronic viral diseases such as human immunodeficiency virus (HIV) and hepatitis B virus (HBV) afflict millions of people worldwide. A key public health challenge in managing such diseases is identifying infected, asymptomatic individuals so that they can receive antiviral treatment. Such treatment can benefit both the treated individual (by improving quality and length of life) and the population as a whole (through reduced transmission). We develop a compartmental model of a chronic, treatable infectious disease and use it to evaluate the cost and effectiveness of different levels of screening and contact tracing. We show that: 1) the optimal strategy is to get infected individuals into treatment at the maximal rate until the incremental health benefits balance the incremental cost of controlling the disease; 2) as one reduces the disease prevalence by moving people into treatment (which decreases the chance that they will infect others), one should increase the level of contact tracing to compensate for the decreased effectiveness of screening; 3) as the disease becomes less prevalent, it is optimal to spend more per case identified; and 4) the relative mix of screening and contact tracing at any level of disease prevalence is such that the marginal efficiency of contact tracing (cost per infected person found) equals that of screening if possible (e.g., when capacity limitations are not binding). We also show how to determine the cost-effective equilibrium level of disease prevalence (among untreated individuals), and we develop an approximation of the path of the optimal prevalence over time. Using this, one can obtain a close approximation of the optimal solution without having to solve an optimal control problem. We apply our methods to an example of hepatitis B virus. PMID:20043926

  17. Digital flight control actuation system study

    NASA Technical Reports Server (NTRS)

    Rossing, R.; Hupp, R.

    1974-01-01

    Flight control actuators and feedback sensors suitable for use in a redundant digital flight control system were examined. The most appropriate design approach for an advanced digital flight control actuation system for development and use in a fly-by-wire system was selected. The concept which was selected consisted of a PM torque motor direct drive. The selected system is compatible with concurrent and independent development efforts on the computer system and the control law mechanizations.

  18. Individual cognitive stimulation therapy for dementia: a clinical effectiveness and cost-effectiveness pragmatic, multicentre, randomised controlled trial.

    PubMed Central

    Orgeta, Vasiliki; Leung, Phuong; Yates, Lauren; Kang, Sujin; Hoare, Zoe; Henderson, Catherine; Whitaker, Chris; Burns, Alistair; Knapp, Martin; Leroi, Iracema; Moniz-Cook, Esme D; Pearson, Stephen; Simpson, Stephen; Spector, Aimee; Roberts, Steven; Russell, Ian T; de Waal, Hugo; Woods, Robert T; Orrell, Martin

    2015-01-01

    BACKGROUND Group cognitive stimulation therapy programmes can benefit cognition and quality of life for people with dementia. Evidence for home-based, carer-led cognitive stimulation interventions is limited. OBJECTIVES To evaluate the clinical effectiveness and cost-effectiveness of carer-delivered individual cognitive stimulation therapy (iCST) for people with dementia and their family carers, compared with treatment as usual (TAU). DESIGN A multicentre, single-blind, randomised controlled trial assessing clinical effectiveness and cost-effectiveness. Assessments were at baseline, 13 weeks and 26 weeks (primary end point). SETTING Participants were recruited through Memory Clinics and Community Mental Health Teams for older people. PARTICIPANTS A total of 356 caregiving dyads were recruited and 273 completed the trial. INTERVENTION iCST consisted of structured cognitive stimulation sessions for people with dementia, completed up to three times weekly over 25 weeks. Family carers were supported to deliver the sessions at home. MAIN OUTCOME MEASURES Primary outcomes for the person with dementia were cognition and quality of life. Secondary outcomes included behavioural and psychological symptoms, activities of daily living, depressive symptoms and relationship quality. The primary outcome for the family carers was mental/physical health (Short Form questionnaire-12 items). Health-related quality of life (European Quality of Life-5 Dimensions), mood symptoms, resilience and relationship quality comprised the secondary outcomes. Costs were estimated from health and social care and societal perspectives. RESULTS There were no differences in any of the primary outcomes for people with dementia between intervention and TAU [cognition: mean difference -0.55, 95% confidence interval (CI) -2.00 to 0.90; p-value = 0.45; self-reported quality of life: mean difference -0.02, 95% CI -1.22 to 0.82; p-value = 0.97 at the 6-month follow-up]. iCST did not improve mental

  19. Effectiveness and cost-effectiveness of a universal parenting skills programme in deprived communities: multicentre randomised controlled trial

    PubMed Central

    Simkiss, D E; Snooks, H A; Stallard, N; Kimani, P K; Sewell, B; Fitzsimmons, D; Anthony, R; Winstanley, S; Wilson, L; Phillips, C J; Stewart-Brown, S

    2013-01-01

    Objective To evaluate the effectiveness and cost utility of a universally provided early years parenting programme. Design Multicentre randomised controlled trial with cost-effectiveness analysis. Setting Early years centres in four deprived areas of South Wales. Participants Families with children aged between 2 and 4 years. 286 families were recruited and randomly allocated to the intervention or waiting list control. Intervention The Family Links Nurturing Programme (FLNP), a 10-week course with weekly 2 h facilitated group sessions. Main outcome measures Negative and supportive parenting, child and parental well-being and costs assessed before the intervention, following the course (3 months) and at 9 months using standardised measures. Results There were no significant differences in primary or secondary outcomes between trial arms at 3 or 9 months. With ‘+’ indicating improvement, difference in change in negative parenting score at 9 months was +0.90 (95%CI −1.90 to 3.69); in supportive parenting, +0.17 (95%CI −0.61 to 0.94); and 12 of the 17 secondary outcomes showed a non-significant positive effect in the FLNP arm. Based on changes in parental well-being (SF-12), the cost per quality-adjusted life year (QALY) gained was estimated to be £34 913 (range 21 485–46 578) over 5 years and £18 954 (range 11 664–25 287) over 10 years. Probability of cost per QALY gained below £30 000 was 47% at 5 years and 57% at 10 years. Attendance was low: 34% of intervention families attended no sessions (n=48); only 47% completed the course (n=68). Also, 19% of control families attended a parenting programme before 9-month follow-up. Conclusions Our trial has not found evidence of clinical or cost utility for the FLNP in a universal setting. However, low levels of exposure and contamination mean that uncertainty remains. Trial registration The trial is registered with Current Controlled Trials ISRCTN13919732. PMID:23906953

  20. Cost-effectiveness of smoking cessation treatment initiated during psychiatric hospitalization: analysis from a randomized, controlled trial

    PubMed Central

    Barnett, Paul G.; Wong, Wynnie; Jeffers, Abra; Hall, Sharon M.; Prochaska, Judith J.

    2016-01-01

    Objective We examined the cost-effectiveness of smoking cessation treatment for psychiatric inpatients. Method Smokers, regardless of intention to quit, were recruited during psychiatric hospitalization and randomized to receive stage-based smoking cessation services or usual aftercare. Smoking cessation services, quality of life, and biochemically-verified abstinence from cigarettes were assessed during 18-months of follow-up. Trial findings were combined with literature on changes in smoking status and the age and gender adjusted effect of smoking on health care cost, mortality, and quality of life in a Markov model of cost-effectiveness during a lifetime horizon. Results Among 223 smokers randomized between 2006 and 2008, the mean cost of smoking cessation services was $189 in the experimental treatment group and $37 in the usual care condition (p < 0.001). At the end of follow-up, 18.75% of the experimental group was abstinent from cigarettes, compared to 6.80% abstinence in the usual care group (p <0.05). The model projected that the intervention added $43 in lifetime cost and generated 0.101 additional Quality Adjusted Life Years (QALYs), an incremental cost-effectiveness ratio of $428 per QALY. Probabilistic sensitivity analysis found the experimental intervention was cost-effective against the acceptance criteria of $50,000/QALY in 99.0% of the replicates. Conclusions A cessation intervention for smokers identified in psychiatric hospitalization did not result in higher mental health care costs in the short-run and was highly cost-effective over the long-term. The stage-based intervention was a feasible and cost-effective way of addressing the high smoking prevalence in persons with serious mental illness. PMID:26528651

  1. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman; Sarah R. Nuss-Warren

    2006-12-31

    This report highlights work done on a project intended to lower the cost of environmental compliance and expedite project permitting for Exploration and Production (E&P) operators by identifying, developing, testing, and commercializing emissions control and monitoring technologies. Promising technologies have already been identified and developed. Current work focuses on testing these promising technologies. Specifically, several technologies are being tested in the laboratory for application to lean-burn engines or fully characterized on-site for use with rich-burn engines. Upon completion of these tests, the most cost-effective and robust technologies will be tested in the field and commercialization will ensue. During this quarter, progress in laboratory testing for lean-burn engines was limited by maintenance issues on the KSU Ajax DP-115. The difficulties that required maintenance to be performed will likely require that the 180 psig prototype valve be tested in the future, if possible. The maintenance was performed, and it is expected that the Ajax will be available for testing in the coming quarter. Although laboratory testing was slowed as a result of maintenance issues, progress in experimental characterization of technologies has been significant. NSCR systems will be characterized as applied to rich-burn engines on-site. This characterization will ensure high-quality data in final field testing on rich-burn engines and is considered to be essential, despite that the work requires the delay of official field testing until 2008. Many preliminary and administrative tasks have been completed, including initial site selection, official proposal submittal, and beginning a process to approve necessary changes to installed field engines.

  2. Muslim communities learning about second-hand smoke: a pilot cluster randomised controlled trial and cost-effectiveness analysis

    PubMed Central

    Shah, Sarwat; Ainsworth, Hannah; Fairhurst, Caroline; Tilbrook, Helen; Sheikh, Aziz; Amos, Amanda; Parrott, Steve; Torgerson, David; Thompson, Heather; King, Rebecca; Mir, Ghazala; Siddiqi, Kamran

    2015-01-01

    Background: In the United Kingdom, men of Bangladeshi and Pakistani origin have higher smoking rates than the general population. This makes non-smokers in their households more vulnerable to second-hand smoke (SHS) exposure than the general population. Aims: The aim of this study was to investigate the feasibility of implementing and pilot testing the effectiveness and cost-effectiveness of a ‘Smoke-free Homes’ (SFH) intervention in Islamic religious settings to encourage families of Bangladeshi and Pakistani origin to apply smoking restrictions in their homes. Methods: We allocated Islamic religious settings (clusters) to either receive SFH—an educational intervention—or to a control arm. Within each cluster, we recruited households with at least one smoker and one non-smoker. SHS exposure among non-smokers was measured using salivary cotinine. Results: Seven (50%) clusters were randomised to each trial arm. A total of 468 households were assessed for eligibility and 62% (n=289) were eligible, of which 74% (n=213) agreed to participate in the trial. Six of the seven intervention clusters delivered the intervention, and all clusters were retained throughout the trial. In all, 81% (n=172) of households provided data at follow-up. No evidence of a difference in log cotinine level was observed (adjusted mean difference −0.02, 95% confidence interval (CI) −1.28–1.23, P=0.97) between the two trial arms. The direct mean cost of delivering the intervention was £18.18 per household (range £3.55–42.20). Conclusions: It was possible to recruit, randomise and retain Islamic religious settings and participant households. However, some of the original assumptions, in particular our ability to collect primary outcome data, need to be revisited before a definitive trial. PMID:26313312

  3. Cost-Effectiveness of a Long-Term Internet-Delivered Worksite Health Promotion Programme on Physical Activity and Nutrition: A Cluster Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Robroek, Suzan J. W.; Polinder, Suzanne; Bredt, Folef J.; Burdorf, Alex

    2012-01-01

    This study aims to evaluate the cost-effectiveness of a long-term workplace health promotion programme on physical activity (PA) and nutrition. In total, 924 participants enrolled in a 2-year cluster randomized controlled trial, with departments (n = 74) within companies (n = 6) as the unit of randomization. The intervention was compared with a…

  4. A Cost-Effectiveness Tool to Guide the Prioritization of Interventions for Rheumatic Fever and Rheumatic Heart Disease Control in African Nations

    PubMed Central

    Lubinga, Solomon J.; Mayosi, Bongani; Babigumira, Joseph B.

    2016-01-01

    Background Rheumatic heart disease (RHD) prevalence and mortality rates remain especially high in many parts of Africa. While effective prevention and treatment exist, coverage rates of the various interventions are low. Little is known about the comparative cost-effectiveness of different RHD interventions in limited resource settings. We developed an economic evaluation tool to assist ministries of health in allocating resources and planning RHD control programs. Methodology/Principal Findings We constructed a Markov model of the natural history of acute rheumatic fever (ARF) and RHD, taking transition probabilities and intervention effectiveness data from previously published studies and expert opinion. Our model estimates the incremental cost-effectiveness of scaling up coverage of primary prevention (PP), secondary prevention (SP) and heart valve surgery (VS) interventions for RHD. We take a healthcare system perspective on costs and measure outcomes as disability-adjusted life-years (DALYs), discounting both at 3%. Univariate and probabilistic sensitivity analyses are also built into the modeling tool. We illustrate the use of this model in a hypothetical low-income African country, drawing on available disease burden and cost data. We found that, in our hypothetical country, PP would be cost saving and SP would be very cost-effective. International referral for VS (e.g., to a country like India that has existing surgical capacity) would be cost-effective, but building in-country VS services would not be cost-effective at typical low-income country thresholds. Conclusions/Significance Our cost-effectiveness analysis tool is designed to inform priorities for ARF/RHD control programs in Africa at the national or subnational level. In contrast to previous literature, our preliminary findings suggest PP could be the most efficient and cheapest approach in poor countries. We provide our model for public use in the form of a Supplementary File. Our research has

  5. Effectiveness and cost-effectiveness of telehealthcare for chronic obstructive pulmonary disease: study protocol for a cluster randomized controlled trial

    PubMed Central

    2014-01-01

    Background Several feasibility studies show promising results of telehealthcare on health outcomes and health-related quality of life for patients suffering from chronic obstructive pulmonary disease, and some of these studies show that telehealthcare may even lower healthcare costs. However, the only large-scale trial we have so far - the Whole System Demonstrator Project in England - has raised doubts about these results since it conclude that telehealthcare as a supplement to usual care is not likely to be cost-effective compared with usual care alone. Methods/Design The present study is known as ‘TeleCare North’ in Denmark. It seeks to address these doubts by implementing a large-scale, pragmatic, cluster-randomized trial with nested economic evaluation. The purpose of the study is to assess the effectiveness and the cost-effectiveness of a telehealth solution for patients suffering from chronic obstructive pulmonary disease compared to usual practice. General practitioners will be responsible for recruiting eligible participants (1,200 participants are expected) for the trial in the geographical area of the North Denmark Region. Twenty-six municipality districts in the region define the randomization clusters. The primary outcomes are changes in health-related quality of life, and the incremental cost-effectiveness ratio measured from baseline to follow-up at 12 months. Secondary outcomes are changes in mortality and physiological indicators (diastolic and systolic blood pressure, pulse, oxygen saturation, and weight). Discussion There has been a call for large-scale clinical trials with rigorous cost-effectiveness assessments in telehealthcare research. This study is meant to improve the international evidence base for the effectiveness and cost-effectiveness of telehealthcare to patients suffering from chronic obstructive pulmonary disease by implementing a large-scale pragmatic cluster-randomized clinical trial. Trial registration Clinicaltrials

  6. Integrated, multidisciplinary care for hand eczema: design of a randomized controlled trial and cost-effectiveness study

    PubMed Central

    2009-01-01

    Background The individual and societal burden of hand eczema is high. Literature indicates that moderate to severe hand eczema is a disease with a poor prognosis. Many patients are hampered in their daily activities, including work. High costs are related to high medical consumption, productivity loss and sick leave. Usual care is suboptimal, due to a lack of optimal instruction and coordination of care, and communication with the general practitioner/occupational physician and people involved at the workplace. Therefore, an integrated, multidisciplinary intervention involving a dermatologist, a care manager, a specialized nurse and a clinical occupational physician was developed. This paper describes the design of a study to investigate the effectiveness and cost-effectiveness of integrated care for hand eczema by a multidisciplinary team, coordinated by a care manager, consisting of instruction on avoiding relevant contact factors, both in the occupational and in the private environment, optimal skin care and treatment, compared to usual, dermatologist-led care. Methods The study is a multicentre, randomized, controlled trial with an economic evaluation alongside. The study population consists of patients with chronic, moderate to severe hand eczema, who visit an outpatient clinic of one of the participating 5 (three university and two general) hospitals. Integrated, multidisciplinary care, coordinated by a care manager, including allergo-dermatological evaluation by a dermatologist, occupational intervention by a clinical occupational physician, and counselling by a specialized nurse on optimizing topical treatment and skin care will be compared with usual care by a dermatologist. The primary outcome measure is the cumulative difference in reduction of the clinical severity score HECSI between the groups. Secondary outcome measures are the patient's global assessment, specific quality of life with regard to the hands, generic quality of life, sick leave and

  7. Digital control system for space structural dampers

    NASA Technical Reports Server (NTRS)

    Haviland, J. K.

    1984-01-01

    Digital control systems for space structural dampers, also referred to as inertia or proof-mass dampers are investigated. A damper concept is improved by adding a small taper to the proof-mass, and using a proximeter to determine position. Another damper using a three inch stroke rather than the standard one inch stroke is described. Provisions are made for a relative velocity feedback. In one approach, the digital controller is modified to accept the signal from a linear velocity transducer. In the other, the velocity feedback is included in the digital program. An overall system concept for the use of the dampers is presented.

  8. Percutaneous Cryoablation of Metastatic Renal Cell Carcinoma for Local Tumor Control: Feasibility, Outcomes, and Estimated Cost-effectiveness for Palliation

    PubMed Central

    Bang, Hyun J.; Littrup, Peter J.; Goodrich, Dylan J.; Currier, Brandt P.; Aoun, Hussein D.; Heilbrun, Lance K.; Vaishampayan, Ulka; Adam, Barbara; Goodman, Allen C.

    2013-01-01

    Purpose To assess complications, local tumor recurrences, overall survival (OS), and estimates of cost-effectiveness for multisite cryoablation (MCA) of oligometastatic renal cell carcinoma (RCC). Materials and Methods A total of 60 computed tomography- and/or ultrasound-guided percutaneous MCA procedures were performed on 72 tumors in 27 patients (three women and 24 men). Average patient age was 63 years. Tumor location was grouped according to common metastatic sites. Established surgical selection criteria graded patient status. Median OS was determined by Kaplan–Meier method and defined life-years gained (LYGs). Estimates of MCA costs per LYG were compared with established values for systemic therapies. Results Total number of tumors and cryoablation procedures for each anatomic site are as follows: nephrectomy bed, 11 and 11; adrenal gland, nine and eight; paraaortic, seven and six; lung, 14 and 13; bone, 13 and 13; superficial, 12 and nine; intraperitoneal, five and three; and liver, one and one. A mean of 2.2 procedures per patient were performed, with a median clinical follow-up of 16 months. Major complication and local recurrence rates were 2% (one of 60) and 3% (two of 72), respectively. No patients were graded as having good surgical risk, but median OS was 2.69 years, with an estimated 5-year survival rate of 27%. Cryoablation remained cost-effective with or without the presence of systemic therapies according to historical cost comparisons, with an adjunctive cost-effectiveness ratio of $28,312–$59,554 per LYG. Conclusions MCA was associated with very low morbidity and local tumor recurrence rates for all anatomic sites, with apparent increased OS. Even as an adjunct to systemic therapies, MCA appeared cost-effective for palliation of oligometastatic RCC. PMID:22538119

  9. Cost-effectiveness of tailored print communication, telephone motivational interviewing, and a combination of the two: results of an economic evaluation alongside the Vitalum randomized controlled trial

    PubMed Central

    2010-01-01

    Background The aim of the present study was to evaluate the cost-effectiveness of tailored print communication (TPC), telephone motivational interviewing (TMI), a combination of the two, and no intervention on two outcomes in adults aged 45 to 70, half of them having hypertension: increasing the number of public health guidelines met for three behaviors (physical activity and fruit and vegetable consumption), and impact on quality adjusted life years (QALYs). Methods Participants (n = 1,629) from 23 Dutch general practices were randomized into one of four groups, which received 4 TPCs, 4 TMIs, 2 of each (combined), or no intervention (control), respectively. The self-reported outcomes, measured at baseline and 73 weeks follow-up (7 months after the last intervention component), were difference in total number of guidelines met at follow-up compared to baseline, and number of QALYs experienced over 73 weeks. The costs of implementing the intervention were estimated using a bottom-up approach. Results At 73 weeks follow-up participants showed increased adherence with 0.62 (TPC), 0.40 (TMI), 0.50 (combined), and 0.26 (control) guidelines compared to baseline, and experienced 1.09, 1.08, 1.08, and 1.07 QALYs, respectively. The costs for the control group were considered to be zero. TMI was more expensive (€107 per person) than both the combined intervention (€80) and TPC (€57). The control condition was most cost-effective for lower ceiling ratios, while TPC had the highest probability of being most cost-effective for higher ceiling ratios (more than €160 per additional guideline met, and €2,851 for each individual QALY). Conclusions For low society's willingness to pay, the control group was most cost-effective for the number of QALYs experienced over 73 weeks. This also applied to the increase in the number of guidelines met at lower ceiling ratios, whereas at higher ceiling ratios, TPC had a higher probability of being more cost-effective than the TMI

  10. Evaluating Multi-Input/Multi-Output Digital Control Systems

    NASA Technical Reports Server (NTRS)

    Pototzky, Anthony S.; Wieseman, Carol D.; Hoadley, Sherwood T.; Mukhopadhyay, Vivek

    1994-01-01

    Controller-performance-evaluation (CPE) methodology for multi-input/multi-output (MIMO) digital control systems developed. Procedures identify potentially destabilizing controllers and confirm satisfactory performance of stabilizing ones. Methodology generic and used in many types of multi-loop digital-controller applications, including digital flight-control systems, digitally controlled spacecraft structures, and actively controlled wind-tunnel models. Also applicable to other complex, highly dynamic digital controllers, such as those in high-performance robot systems.

  11. Cost-Effectiveness of Strategies to Improve HIV Testing and Receipt of Results: Economic Analysis of a Randomized Controlled Trial

    PubMed Central

    Anaya, Henry D.; Asch, Steven; Hoang, Tuyen; Golden, Joya F.; Bayoumi, Ahmed M.; Owens, Douglas K.

    2010-01-01

    Background The CDC recommends routine voluntary HIV testing of all patients 13-64 years of age. Despite this recommendation, HIV testing rates are low even among those at identifiable risk, and many patients do not return to receive their results. Objective To examine the costs and benefits of strategies to improve HIV testing and receipt of results. Design Cost-effectiveness analysis based on a Markov model. Acceptance of testing, return rates, and related costs were derived from a randomized trial of 251 patients; long-term costs and health outcomes were derived from the literature. Setting/target population Primary-care patients with unknown HIV status. Interventions Comparison of three intervention models for HIV counseling and testing: Model A = traditional HIV counseling and testing; Model B = nurse-initiated routine screening with traditional HIV testing and counseling; Model C = nurse-initiated routine screening with rapid HIV testing and streamlined counseling. Main measures Life-years, quality-adjusted life-years (QALYs), costs and incremental cost-effectiveness. Key results Without consideration of the benefit from reduced HIV transmission, Model A resulted in per-patient lifetime discounted costs of $48,650 and benefits of 16.271 QALYs. Model B increased lifetime costs by $53 and benefits by 0.0013 QALYs (corresponding to 0.48 quality-adjusted life days). Model C cost $66 more than Model A with an increase of 0.0018 QALYs (0.66 quality-adjusted life days) and an incremental cost-effectiveness of $36,390/QALY. When we included the benefit from reduced HIV transmission, Model C cost $10,660/QALY relative to Model A. The cost-effectiveness of Model C was robust in sensitivity analyses. Conclusions In a primary-care population, nurse-initiated routine screening with rapid HIV testing and streamlined counseling increased rates of testing and receipt of test results and was cost-effective compared with traditional HIV testing strategies. Electronic

  12. Assessing the effectiveness and cost-effectiveness of audit and feedback on physician’s prescribing indicators: study protocol of a randomized controlled trial with economic evaluation

    PubMed Central

    2012-01-01

    Background Physician prescribing is the most frequent medical intervention with a highest impact on healthcare costs and outcomes. Therefore improving and promoting rational drug use is a great interest. We aimed to assess the effectiveness and cost-effectiveness of two forms of conducting prescribing audit and feedback interventions and a printed educational material intervention in improving physician prescribing. Method/design A four-arm randomized trial with economic evaluation will be conducted in Tehran. Three interventions (routine feedback, revised feedback, and printed educational material) and a no intervention control arm will be compared. Physicians working in outpatient practices are randomly allocated to one of the four arms using stratified randomized sampling. The interventions are developed based on a review of literature, physician interviews, current experiences in Iran and with theoretical insights from the Theory of Planned Behavior. Effects of the interventions on improving antibiotics and corticosteroids prescribing will be assessed in regression analyses. Cost data will be assessed from a health care provider’s perspective and incremental cost-effectiveness ratios will be calculated. Discussion This study will determine the effectiveness and cost-effectiveness of three interventions and allow us to determine the most effective interventions in improving prescribing pattern. If the interventions are cost-effective, they will likely be applied nationwide. Trial registration Iranian Registry of Clinical Trials Registration Number: IRCT201106086740N1Pharmaceutical Sciences Research Center of TUMS Ethics Committee Registration Number: 90-02-27-07 PMID:23351564

  13. Are lower levels of red blood cell transfusion more cost-effective than liberal levels after cardiac surgery? Findings from the TITRe2 randomised controlled trial

    PubMed Central

    Stokes, E A; Wordsworth, S; Bargo, D; Pike, K; Rogers, C A; Brierley, R C M; Angelini, G D; Murphy, G J; Reeves, B C

    2016-01-01

    Objective To assess the incremental cost and cost-effectiveness of a restrictive versus a liberal red blood cell transfusion threshold after cardiac surgery. Design A within-trial cost-effectiveness analysis with a 3-month time horizon, based on a multicentre superiority randomised controlled trial from the perspective of the National Health Service (NHS) and personal social services in the UK. Setting 17 specialist cardiac surgery centres in UK NHS hospitals. Participants 2003 patients aged >16 years undergoing non-emergency cardiac surgery with a postoperative haemoglobin of <9 g/dL. Interventions Restrictive (transfuse if haemoglobin <7.5 g/dL) or liberal (transfuse if haemoglobin <9 g/dL) threshold during hospitalisation after surgery. Main outcome measures Health-related quality of life measured using the EQ-5D-3L to calculate quality-adjusted life years (QALYs). Results The total costs from surgery up to 3 months were £17 945 and £18 127 in the restrictive and liberal groups (mean difference is −£182, 95% CI −£1108 to £744). The cost difference was largely attributable to the difference in the cost of red blood cells. Mean QALYs to 3 months were 0.18 in both groups (restrictive minus liberal difference is 0.0004, 95% CI −0.0037 to 0.0045). The point estimate for the base-case cost-effectiveness analysis suggested that the restrictive group was slightly more effective and slightly less costly than the liberal group and, therefore, cost-effective. However, there is great uncertainty around these results partly due to the negligible differences in QALYs gained. Conclusions We conclude that there is no clear difference in the cost-effectiveness of restrictive and liberal thresholds for red blood cell transfusion after cardiac surgery. Trial registration number ISRCTN70923932; Results. PMID:27481621

  14. Cost-effectiveness of screening for anal cancer using regular digital ano-rectal examinations in men who have sex with men living with HIV

    PubMed Central

    Ong, Jason J; Fairley, Christopher K; Carroll, Susan; Walker, Sandra; Chen, Marcus; Read, Tim; Grulich, Andrew; Bradshaw, Catriona; Kaldor, John; Clarke, Philip

    2016-01-01

    Introduction Anal cancer in men who have sex with men (MSM) living with HIV is an important issue but there are no consistent guidelines for how to screen for this cancer. In settings where screening with anal cytology is unavailable, regular anal examinations have been proposed in some guidelines but their cost-effectiveness is unknown. Methods Our objective was to estimate the cost-effectiveness of regular anal examinations to screen for anal cancer in HIV-positive MSM living in Australia using a probabilistic Markov model. Data sources were based on the medical literature and a clinical trial of HIV-positive MSM receiving an annual anal examination in Australia. The main outcome measures for calculating effectiveness were undiscounted and discounted (at 3%) lifetime costs, life years gained, quality-adjusted life years (QALY) gained and incremental cost-effectiveness ratio (ICER). Results Base-case analysis estimated the average cost of screening for and management of anal cancer ranged from $195 for no screening to $1,915 for lifetime annual screening of men aged ≥ 50. Screening of men aged ≥ 50 generated ICERs of $29,760 per QALY gained (for screening every four years), $32,222 (every three years) and $45,484 (every two years). Uncertainty for ICERs was mostly influenced by the cost (financially and decrease in quality of life) from a false-positive result, progression rate of anal cancer, specificity of the anal examination, the probability of detection outside a screening program and the discount rate. Conclusions Screening for anal cancer by incorporating regular anal examinations into routine HIV care for MSM aged ≥ 50 is most likely to be cost-effective by conventional standards. Given that anal pap smears are not widely available yet in many clinical settings, regular anal exams for MSM living with HIV to detect anal cancer earlier should be implemented. PMID:26942721

  15. Cost-effectiveness of an experimental caries-control regimen in a 3.4-yr randomized clinical trial among 11-12-yr-old Finnish schoolchildren.

    PubMed

    Hietasalo, Pauliina; Seppä, Liisa; Lahti, Satu; Niinimaa, Ahti; Kallio, Jouko; Aronen, Pasi; Sintonen, Harri; Hausen, Hannu

    2009-12-01

    The aim of this study was to assess the cost-effectiveness of an experimental caries-control regimen in a randomized clinical trial (RCT) conducted in Pori, Finland, in 2001-2005. Children (n = 497) who were 11-12 yr of age and had at least one active initial caries lesion at baseline were studied. The children in the experimental group (n = 250) were offered an individually designed patient-centered regimen for caries control. The children in the control group (n = 247) received standard dental care. Furthermore, the whole population was exposed to continuous community-level oral health promotion. Individual costs of treatment procedures and outcomes (DMFS increment score) for the follow-up period of 3.4 yr were calculated for each child in both groups. The incremental cost-effectiveness ratio was euro 34.07 per averted DMF surface. The experimental regimen was more effective, and also more costly. However, the total costs decreased year after year, and for the last 2 yr the experimental regimen was less expensive than the standard dental care. The experimental regimen would probably have been more cost-effective than standard dental care if the follow-up period had been longer, the regimen less comprehensive, and/or if dental nurses had conducted the preventive procedures. PMID:20121937

  16. Digital control system for space structure dampers

    NASA Technical Reports Server (NTRS)

    Haviland, J. K.

    1985-01-01

    A digital controller was developed using an SKD-51 System Design Kit, which incorporates an 8031 microcontroller. The necessary interfaces were installed in the wire wrap area of the SKD-51 and a pulse width modulator was developed to drive the coil of the actuator. Also, control equations were developed, using floating-point arithmetic. The design of the digital control system is emphasized, and it is shown that, provided certain rules are followed, an adequate design can be achieved. It is recommended that the so-called w-plane design method be used, and that the time elapsed before output of the up-dated coil-force signal be kept as small as possible. However, the cycle time for the controller should be watched carefully, because very small values for this time can lead to digital noise.

  17. Cost-effectiveness of a national exercise referral programme for primary care patients in Wales: results of a randomised controlled trial

    PubMed Central

    2013-01-01

    Background A recent HTA review concluded that there was a need for RCTs of exercise referral schemes (ERS) for people with a medical diagnosis who might benefit from exercise. Overall, there is still uncertainty as to the cost-effectiveness of ERS. Evaluation of public health interventions places challenges on conventional health economics approaches. This economic evaluation of a national public health intervention addresses this issue of where ERS may be most cost effective through subgroup analysis, particularly important at a time of financial constraint. Method This economic analysis included 798 individuals aged 16 and over (55% of the randomised controlled trial (RCT) sample) with coronary heart disease risk factors and/or mild to moderate anxiety, depression or stress. Individuals were referred by health professionals in a primary care setting to a 16 week national exercise referral scheme (NERS) delivered by qualified exercise professionals in local leisure centres in Wales, UK. Health-related quality of life, health care services use, costs per participant in NERS, and willingness to pay for NERS were measured at 6 and 12 months. Results The base case analysis assumed a participation cost of £385 per person per year, with a mean difference in QALYs between the two groups of 0.027. The incremental cost-effectiveness ratio was £12,111 per QALY gained. Probabilistic sensitivity analysis demonstrated an 89% probability of NERS being cost-effective at a payer threshold of £30,000 per QALY. When participant payments of £1 and £2 per session were considered, the cost per QALY fell from £12,111 (base case) to £10,926 and £9,741, respectively. Participants with a mental health risk factor alone or in combination with a risk of chronic heart disease generated a lower ICER (£10,276) compared to participants at risk of chronic heart disease only (£13,060). Conclusions Results of cost-effectiveness analyses suggest that NERS is cost saving in fully

  18. Digital controller for high pressure rocket engine.

    NASA Technical Reports Server (NTRS)

    Thompson, Z.; Cummings, W. J.; Hall, D. M.

    1972-01-01

    Description of a general approach for the design of an adaptive digital control system for liquid bipropellant rocket engines. The technique employs linearized transfer functions derived from perturbations of an engine simulation. The linear models serve as a basis on which to develop candidate closed-loop control laws quickly and economically.

  19. Multicentre aneurysm screening study (MASS): cost effectiveness analysis of screening for abdominal aortic aneurysms based on four year results from randomised controlled trial

    PubMed Central

    2002-01-01

    Objective To assess the cost effectiveness of ultrasound screening for abdominal aortic aneurysms. Design Primary analysis: four year cost effectiveness analysis based directly on results from a randomised controlled trial in which patients were individually allocated to invitation to ultrasound screening (intervention) or to a control group not offered screening. Secondary analysis: projection of the data, based on conservative assumptions, to indicate likely cost effectiveness at 10 years. Setting Four centres in the United Kingdom. Screening delivered in primary care settings with follow up and surgery offered in the main hospitals Participants Population based sample of 67 800 men aged 65-74 years. Main outcome measures Mortality from and costs (screening, follow up, elective and emergency surgery) related to abdominal aortic aneurysm; cost per life year gained. Results Over four years there were 47 fewer deaths related to abdominal aortic aneurysms in the screening group than in the control group, but the additional costs incurred were £2.2m. After adjustment for censoring and discounted at 6% the mean additional cost of the screening programme was £63.39 ($97.77, €100.48) (95% confidence interval £53.31 to £73.48) per patient. The hazard ratio for abdominal aortic aneurysm was 0.58 (0.42 to 0.78). Over four years the mean incremental cost effectiveness ratio for screening was £28 400 (£15 000 to £146 000) per life year gained, equivalent to about £36 000 per quality adjusted life year. After 10 years this figure is estimated to fall to around £8000 per life year gained. Conclusions Even at four years the cost effectiveness of screening for abdominal aortic aneurysms is at the margin of acceptability according to current NHS thresholds. Over a longer period the cost effectiveness will improve substantially, the predicted ratio at 10 years falling to around a quarter of the four year figure. What is already known on this topicSmall trials

  20. Digital attitude control for NASA sounding rockets

    NASA Astrophysics Data System (ADS)

    Martinez, Carlos

    1998-11-01

    Various configurations of Solar Pointing Control Systems have been used for NASA sounding rockets since an initial flight in December of 1967. Until now, these attitude control systems have used an analog controller. The demand for a more advanced attitude control system with better performance and flexibility leads to the testing of a digital control system. Computer aided design was used to develop the control equations and an embedded controller is used to implement these equations. The analog control system pointing performance was degraded by electrical noise and offsets getting into the sensor signals. The solution to this problem was to isolate the sun sensor from payload electrical nose and ground loops. To accomplish this the sun sensor output was digitized and the data was sent to the control system using a fiber optical cable. This control system was flown on Naval Research Laboratories rocket 36.140 and had less than 0.5 arc-second peak-to-peak jitter during the flight. With further refinements the digital system is expected to attain jitter of less than 0.2 arc- seconds peak-to-peak.

  1. Aid For Simulating Digital Flight Control Systems

    NASA Technical Reports Server (NTRS)

    Hartman, Richard M.

    1991-01-01

    DIVERS translator is computer program to convert descriptions of digital flight-control systems (DFCS) into computer program. Language developed to represent design charts of DFCS. Translator converts DIVERS source code into easily transportable language, while minimizing probability that results are affected by interpretation of programmer. Final translated program used as standard of comparison to verify operation of actual flight-control systems. Applicable to simulation of other control systems; for example, electrical circuits and logic processes. Written in C.

  2. Cost effectiveness of disc prosthesis versus lumbar fusion in patients with chronic low back pain: randomized controlled trial with 2-year follow-up.

    PubMed

    Fritzell, Peter; Berg, Svante; Borgström, Fredrik; Tullberg, Tycho; Tropp, Hans

    2011-07-01

    This randomized controlled health economic study assesses the cost-effectiveness of the concept of total disc replacement (TDR) (Charité/Prodisc/Maverick) when compared with the concept of instrumented lumbar fusion (FUS) [posterior lumbar fusion (PLF) /posterior lumbar interbody fusion (PLIF)]. Social and healthcare perspectives after 2 years are reported. In all, 152 patients were randomized to either TDR (n = 80) or lumbar FUS (n = 72). Cost to society (total mean cost/patient, Swedish kronor = SEK, standard deviation) for TDR was SEK 599,560 (400,272), and for lumbar FUS SEK 685,919 (422,903) (ns). The difference was not significant: SEK 86,359 (-45,605 to 214,332). TDR was significantly less costly from a healthcare perspective, SEK 22,996 (1,202 to 43,055). Number of days on sick leave among those who returned to work was 185 (146) in the TDR group, and 252 (189) in the FUS group (ns). Using EQ-5D, the total gain in quality adjusted life years (QALYs) over 2 years was 0.41 units for TDR and 0.40 units for FUS (ns). Based on EQ-5D, the incremental cost-effectiveness ratio (ICER) of using TDR instead of FUS was difficult to analyze due to the "non-difference" in treatment outcome, which is why cost/QALY was not meaningful to define. Using cost-effectiveness probabilistic analysis, the net benefit (with CI) was found to be SEK 91,359 (-73,643 to 249,114) (ns). We used the currency of 2006 where 1 EURO = 9.26 SEK and 1 USD = 7.38 SEK. It was not possible to state whether TDR or FUS is more cost-effective after 2 years. Since disc replacement and lumbar fusion are based on different conceptual approaches, it is important to follow these results over time. PMID:21053028

  3. Cost effectiveness of patient education for the prevention of falls in hospital: economic evaluation from a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Falls are one of the most frequently occurring adverse events that impact upon the recovery of older hospital inpatients. Falls can threaten both immediate and longer-term health and independence. There is need to identify cost-effective means for preventing falls in hospitals. Hospital-based falls prevention interventions tested in randomized trials have not yet been subjected to economic evaluation. Methods Incremental cost-effectiveness analysis was undertaken from the health service provider perspective, over the period of hospitalization (time horizon) using the Australian Dollar (A$) at 2008 values. Analyses were based on data from a randomized trial among n = 1,206 acute and rehabilitation inpatients. Decision tree modeling with three-way sensitivity analyses were conducted using burden of disease estimates developed from trial data and previous research. The intervention was a multimedia patient education program provided with trained health professional follow-up shown to reduce falls among cognitively intact hospital patients. Results The short-term cost to a health service of one cognitively intact patient being a faller could be as high as A$14,591 (2008). The education program cost A$526 (2008) to prevent one cognitively intact patient becoming a faller and A$294 (2008) to prevent one fall based on primary trial data. These estimates were unstable due to high variability in the hospital costs accrued by individual patients involved in the trial. There was a 52% probability the complete program was both more effective and less costly (from the health service perspective) than providing usual care alone. Decision tree modeling sensitivity analyses identified that when provided in real life contexts, the program would be both more effective in preventing falls among cognitively intact inpatients and cost saving where the proportion of these patients who would otherwise fall under usual care conditions is at least 4.0%. Conclusions This economic

  4. Cost-Effectiveness of Financial Incentives to Promote Adherence to Depot Antipsychotic Medication: Economic Evaluation of a Cluster-Randomised Controlled Trial

    PubMed Central

    Henderson, Catherine; Knapp, Martin; Yeeles, Ksenija; Bremner, Stephen; Eldridge, Sandra; David, Anthony S.; O’Connell, Nicola; Burns, Tom; Priebe, Stefan

    2015-01-01

    Background Offering a modest financial incentive to people with psychosis can promote adherence to depot antipsychotic medication, but the cost-effectiveness of this approach has not been examined. Methods Economic evaluation within a pragmatic cluster-randomised controlled trial. 141 patients under the care of 73 teams (clusters) were randomised to intervention or control; 138 patients with diagnoses of schizophrenia, schizo-affective disorder or bipolar disorder participated. Intervention participants received £15 per depot injection over 12 months, additional to usual acute, mental and community primary health services. The control group received usual health services. Main outcome measures: incremental cost per 20% increase in adherence to depot antipsychotic medication; incremental cost of ‘good’ adherence (defined as taking at least 95% of the prescribed number of depot medications over the intervention period). Findings Economic and outcome data for baseline and 12-month follow-up were available for 117 participants. The adjusted difference in adherence between groups was 12.2% (73.4% control vs. 85.6% intervention); the adjusted costs difference was £598 (95% CI -£4 533, £5 730). The extra cost per patient to increase adherence to depot medications by 20% was £982 (95% CI -£8 020, £14 000). The extra cost per patient of achieving 'good' adherence was £2 950 (CI -£19 400, £27 800). Probability of cost-effectiveness exceeded 97.5% at willingness-to-pay values of £14 000 for a 20% increase in adherence and £27 800 for good adherence. Interpretation Offering a modest financial incentive to people with psychosis is cost-effective in promoting adherence to depot antipsychotic medication. Direct healthcare costs (including costs of the financial incentive) are unlikely to be increased by this intervention. Trial Registration ISRCTN.com 77769281 PMID:26448540

  5. Digital control of highly augmented combat rotorcraft

    NASA Technical Reports Server (NTRS)

    Tischler, Mark B.

    1987-01-01

    Proposed concepts for the next generation of combat helicopters are to be embodied in a complex, highly maneuverable, multiroled vehicle with avionics systems. Single pilot and nap-of-the-Earth operations require handling qualities which minimize the involvement of the pilot in basic stabilization tasks. To meet these requirements will demand a full authority, high-gain, multimode, multiply-redundant, digital flight-control system. The gap between these requirements and current low-authority, low-bandwidth operational rotorcraft flight-control technology is considerable. This research aims at smoothing the transition between current technology and advanced concept requirements. The state of the art of high-bandwidth digital flight-control systems are reviewed; areas of specific concern for flight-control systems of modern combat are exposed; and the important concepts are illustrated in design and analysis of high-gain, digital systems with a detailed case study involving a current rotorcraft system. Approximate and exact methods are explained and illustrated for treating the important concerns which are unique to digital systems.

  6. Aircraft digital flight control technical review

    NASA Technical Reports Server (NTRS)

    Davenport, Otha B.; Leggett, David B.

    1993-01-01

    The Aircraft Digital Flight Control Technical Review was initiated by two pilot induced oscillation (PIO) incidents in the spring and summer of 1992. Maj. Gen. Franklin (PEO) wondered why the Air Force development process for digital flight control systems was not preventing PIO problems. Consequently, a technical review team was formed to examine the development process and determine why PIO problems continued to occur. The team was also to identify the 'best practices' used in the various programs. The charter of the team was to focus on the PIO problem, assess the current development process, and document the 'best practices.' The team reviewed all major USAF aircraft programs with digital flight controls, specifically, the F-15E, F-16C/D, F-22, F-111, C-17, and B-2. The team interviewed contractor, System Program Office (SPO), and Combined Test Force (CTF) personnel on these programs. The team also went to NAS Patuxent River to interview USN personnel about the F/A-18 program. The team also reviewed experimental USAF and NASA systems with digital flight control systems: X-29, X-31, F-15 STOL and Maneuver Technology Demonstrator (SMTD), and the Variable In-Flight Stability Test Aircraft (VISTA). The team also discussed the problem with other experts in the field including Ralph Smith and personnel from Calspan. The major conclusions and recommendations from the review are presented.

  7. Digital techniques applied to sine test control

    NASA Astrophysics Data System (ADS)

    Westoby, T. J.

    1981-09-01

    Digital techniques are applied to solve problems experienced in analogue circuitry, enabling the design of a highly reliable sine control system. A sine wave is generated whose frequency is proportional to a digital number, held in the counters of the sweep generator, using the frequency related pulse stream. This pulse stream is used to generate a ramp by applying it to a count. The rate of rise is varied by using a rate multiplier arranged to slow the pulse stream as the ramp proceeds. Variation of frequency depends only on the frequency of the pulse stream entering the circuit, and the oscillator runs quite acceptably at 0.1 Hz and 10 kHz. The total distortion at this stage is less than 2%. Since the control signal is quantized, only discrete changes in control are experienced, and the control lines are static most of the time; the digital system can reduce the effects of a noisy return signal by as much as 64 times. The greatest advantage of digital techniques is its use in integrator stabilization. A tracking capacitor ensures that conversion is done to an accuracy of 1%, and residual ripple on the output is removed by a low pass filter.

  8. Decentralized digital adaptive control of robot motion

    NASA Technical Reports Server (NTRS)

    Tarokh, M.

    1990-01-01

    A decentralized model reference adaptive scheme is developed for digital control of robot manipulators. The adaptation laws are derived using hyperstability theory, which guarantees asymptotic trajectory tracking despite gross robot parameter variations. The control scheme has a decentralized structure in the sense that each local controller receives only its joint angle measurement to produce its joint torque. The independent joint controllers have simple structures and can be programmed using a very simple and computationally fast algorithm. As a result, the scheme is suitable for real-time motion control.

  9. Guidelines for selection and application of the most cost-effective NO sub x control technologies for gas, oil and coal fired boilers

    SciTech Connect

    Czerniak, D.O.; Booth, R.B.; McDonald, B.L. ); Feenstra, D.R. )

    1991-01-01

    As a result of the new Clean Air Act, lower NO{sub x} emissions from stationary sources will be required of utilities and independent power producers that burn all fuels including gas, oil and coal. This new legislation, as well as new and more stringent NO{sub x} reduction orders imposed by state and local regulatory agencies, will require rapid evaluation, purchase, installation and start-up of a variety of control technologies. There is substantial volume of literature available discussing NO{sub x} control technologies, their control effectiveness, costs, and chemical reaction mechanisms in forming NO{sub x}. This paper, however, presents more practical aspects of developing a NO{sub x} control strategy and implementing the appropriate cost-effective control technology on a utility or industrial boiler.

  10. Quadruplex digital flight control system assessment

    NASA Technical Reports Server (NTRS)

    Mulcare, D. B.; Downing, L. E.; Smith, M. K.

    1988-01-01

    Described are the development and validation of a double fail-operational digital flight control system architecture for critical pitch axis functions. Architectural tradeoffs are assessed, system simulator modifications are described, and demonstration testing results are critiqued. Assessment tools and their application are also illustrated. Ultimately, the vital role of system simulation, tailored to digital mechanization attributes, is shown to be essential to validating the airworthiness of full-time critical functions such as augmented fly-by-wire systems for relaxed static stability airplanes.

  11. Evaluating the efficacy and cost-effectiveness of web-based indicated prevention of major depression: design of a randomised controlled trial

    PubMed Central

    2014-01-01

    Background Major depressive disorder (MDD) imposes a considerable disease burden on individuals and societies. Web-based interventions have shown to be effective in reducing depressive symptom severity. However, it is not known whether web-based interventions may also be effective in preventing the onset of MDD. The aim of this study is to evaluate the (cost-) effectiveness of an indicated web-based guided self-help intervention (GET.ON Mood Enhancer Prevention) on the onset of MDD. Methods/Design A randomised controlled trial (RCT) will be conducted to compare the (cost-) effectiveness of the GET.ON Mood Enhancer Prevention training with a control condition exclusively receiving online-based psychoeducation on depression. Adults with subthreshold depression (N = 406) will be recruited from the general population and randomised to one of the two conditions. The primary outcome is time to onset of MDD within a 12-months follow-up period. MDD will be assessed according to DSM-IV criteria as assessed by the telephone-administered Structured Clinical Interview for DSM-IV (SCID). Time to onset of MDD will be assessed using life charts. Secondary outcomes include changes on various indicators of depressive symptom severity, anxiety and quality of life from baseline to post-treatment, to a 6-month and a 12-month follow up. Additionally, an economic evaluation using a societal perspective will be conducted to examine the intervention’s cost-effectiveness. Discussion This is one of the first randomised controlled trials that examines the effect of an indicated guided self-help web-based intervention on the incidence of major depression. If shown to be effective, the intervention will contribute to reducing the disease burden due to MDD in the general population. Trial registration German Clinical Trial Registration DRKS00004709. PMID:24485283

  12. Cost-effectiveness of interventions to control cardiovascular diseases and type 2 diabetes mellitus in South Asia: protocol for a systematic review

    PubMed Central

    Singh, Kavita; Chandra Sekaran, Ambalam M; Bhaumik, Soumyadeep; Aisola, Malini; Chattopadhyay, Kaushik; Gamage, Anuji U; de Silva, Padmal; Selvaraj, Sakthivel; Roy, Ambuj; Prabhakaran, Dorairaj; Tandon, Nikhil

    2015-01-01

    Introduction While a number of strategies are being implemented to control cardiovascular diseases (CVDs) and type 2 diabetes mellitus (T2DM), the cost-effectiveness of these in the South Asian context has not been systematically evaluated. We aim to systematically review the economic (cost-effectiveness) evidence available on the individual-, group- and population-level interventions for control of CVD and T2DM in South Asia. Methods and analysis This review will consider all relevant economic evaluations, either conducted alongside randomised controlled trials or based on decision modelling estimates. These studies must include participants at risk of developing CVD/T2DM or with established disease in one or more of the South Asian countries (India, Bangladesh, Pakistan, Sri Lanka, Nepal, Maldives, Bhutan and Afghanistan). We will identify relevant papers by systematically searching all major databases and registries. Selected articles will be screened by two independent researchers. Methodological quality of the studies will be assessed using a modified Drummond and a Phillips checklist. Cochrane guidelines will be followed for bias assessment in the effectiveness studies. Results Results will be presented in line with the PRISMA (Preferred Reporting Items for Systematic review and Meta-analysis) checklist, and overall quality of evidence will be presented as per the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) approach. Ethics and dissemination The study has received ethics approval from the All India Institute of Medical Sciences, New Delhi, India. The results of this review will provide policy-relevant recommendations for the uptake of cost-effectiveness evidence in prioritising decisions on essential chronic disease care packages for South Asia. Study registration number PROSPERO CRD42013006479. PMID:25757948

  13. Effectiveness and cost-effectiveness of meaning-centered group psychotherapy in cancer survivors: protocol of a randomized controlled trial

    PubMed Central

    2014-01-01

    Background Meaning-focused coping may be at the core of adequate adjustment to life after cancer. Cancer survivors who experience their life as meaningful are better adjusted, have better quality of life and psychological functioning. Meaning-Centered Group Psychotherapy for Cancer Survivors (MCGP-CS) was designed to help patients to sustain or enhance a sense of meaning and purpose in their lives. The aim of the proposed study is to evaluate the effectiveness and cost-effectiveness of MCGP-CS. Methods/Design Survivors diagnosed with cancer in the last 5 years and treated with curative intent, are recruited via several hospitals in the Netherlands. After screening, 168 survivors are randomly assigned to one of the three study arms: 1. Meaning-Centered Group Psychotherapy (MCGP-CS) 2. Supportive group psychotherapy (SGP) 3. Care as usual (CAU). Baseline assessment takes place before randomisation, with follow up assessments post-intervention and at 3, 6 and 12 months follow-up. Primary outcome is meaning making (PMP, PTGI, SPWB). Secondary outcome measures address quality of life (EORTC-30), anxiety and depression (HADS), hopelessness (BHS), optimism (LOT-R), adjustment to cancer (MAC), and costs (TIC-P, EQ-5D, PRODISQ). Discussion Meaning-focused coping is key to adjustment to life after cancer, however, there is a lack of evidence based psychological interventions in this area. Many cancer survivors experience feelings of loneliness and alienation, and have a need for peer support, therefore a group method in particular, can be beneficial for sustaining or enhancing a sense of meaning. If this MCGP-CS is effective for cancer survivors, it can be implemented in the practice of psycho-oncology care. Trial registration Netherlands Trial Register, NTR3571 PMID:24467861

  14. Digital gate pulse generator for cycloconverter control

    DOEpatents

    Klein, Frederick F.; Mutone, Gioacchino A.

    1989-01-01

    The present invention provides a digital gate pulse generator which controls the output of a cycloconverter used for electrical power conversion applications by determining the timing and delivery of the firing pulses to the switching devices in the cycloconverter. Previous gate pulse generators have been built with largely analog or discrete digital circuitry which require many precision components and periodic adjustment. The gate pulse generator of the present invention utilizes digital techniques and a predetermined series of values to develop the necessary timing signals for firing the switching device. Each timing signal is compared with a reference signal to determine the exact firing time. The present invention is significantly more compact than previous gate pulse generators, responds quickly to changes in the output demand and requires only one precision component and no adjustments.

  15. MBD-seq as a cost-effective approach for methylome-wide association studies: demonstration in 1500 case–control samples

    PubMed Central

    Aberg, Karolina A; McClay, Joseph L; Nerella, Srilaxmi; Xie, Lin Y; Clark, Shaunna L; Hudson, Alexandra D; Bukszár, Jozsef; Adkins, Daniel; Consortium, Swedish Schizophrenia; Hultman, Christina M; Sullivan, Patrick F; Magnusson, Patrik KE; van den Oord, Edwin JCG

    2013-01-01

    Aim We studied the use of methyl-CpG binding domain (MBD) protein-enriched genome sequencing (MBD-seq) as a cost-effective screening tool for methylome-wide association studies (MWAS). Materials & methods Because MBD-seq has not yet been applied on a large scale, we first developed and tested a pipeline for data processing using 1500 schizophrenia cases and controls plus 75 technical replicates with an average of 68 million reads per sample. This involved the use of technical replicates to optimize quality control for multi- and duplicate-reads, an in silico experiment to identify CpGs in loci with alignment problems, CpG coverage calculations based on multiparametric estimates of the fragment size distribution, a two-stage adaptive algorithm to combine data from correlated adjacent CpG sites, principal component analyses to control for confounders and new software tailored to handle the large data set. Results We replicated MWAS findings in independent samples using a different technology that provided single base resolution. In an MWAS of age-related methylation changes, one of our top findings was a previously reported robust association involving GRIA2. Our results also suggested that owing to the many confounding effects, a considerable challenge in MWAS is to identify those effects that are informative about disease processes. Conclusion This study showed the potential of MBD-seq as a cost-effective tool in large-scale disease studies. PMID:23244307

  16. Stay@Work: Participatory Ergonomics to prevent low back and neck pain among workers: design of a randomised controlled trial to evaluate the (cost-)effectiveness

    PubMed Central

    Driessen, Maurice T; Anema, Johannes R; Proper, Karin I; Bongers, Paulien M; Beek, Allard J van der

    2008-01-01

    Background Low back pain (LBP) and neck pain (NP) are a major public health problem with considerable costs for individuals, companies and society. Therefore, prevention is imperative. The Stay@Work study investigates the (cost-)effectiveness of Participatory Ergonomics (PE) to prevent LBP and NP among workers. Methods In a randomised controlled trial (RCT), a total of 5,759 workers working at 36 departments of four companies is expected to participate in the study at baseline. The departments consisting of about 150 workers are pre-stratified and randomised. The control departments receive usual practice and the intervention departments receive PE. Within each intervention department a working group is formed including eight workers, a representative of the management, and an occupational health and safety coordinator. During a one day meeting, the working group follows the steps of PE in which the most important risk factors for LBP and NP, and the most adequate ergonomic measures are identified on the basis of group consensus. The implementation of ergonomic measures at the department is performed by the working group. To improve the implementation process, so-called 'ergocoaches' are trained. The primary outcome measure is an episode of LBP and NP. Secondary outcome measures are actual use of ergonomic measures, physical workload, psychosocial workload, intensity of pain, general health status, sick leave, and work productivity. The cost-effectiveness analysis is performed from the societal and company perspective. Outcome measures are assessed using questionnaires at baseline and after 6 and 12 months. Data on the primary outcome as well as on intensity of pain, sick leave, work productivity, and health care costs are collected every 3 months. Discussion Prevention of LBP and NP is beneficial for workers, employers, and society. If the intervention is proven (cost-)effective, the intervention can have a major impact on LBP and NP prevention and, thereby, on

  17. Digital control algorithms for microgravity isolation systems

    NASA Technical Reports Server (NTRS)

    Sinha, Alok; Wang, Yung-Peng

    1992-01-01

    New digital control algorithms were developed to achieve the desired acceleration transmissibility function. The attractive electromagnets have been taken as actuators. The relative displacement and the acceleration of the mass were used as feedback signals. Two approaches were developed to find that controller transfer function in Z-domain, which yields the desired transmissibility at each frequency. In the first approach, the controller transfer function is obtained by assuming that the desired transmissibility is known in Z-domain. Since the desired transmissibility H sub d(S) = 1/(tauS+1)(exp 2) is given in S-domain, the first task is to obtain the desired transmissibility in Z-domain. There are three methods to perform this task: bilinear transformation, and backward and forward rectangular rules. The bilinear transformation and backward rectangular rule lead to improper controller transfer functions, which are physically not realizable. The forward rectangular rule does lead to a physically realizable controller. However, this controller is found to be marginally stable because of a pole at Z=1. In order to eliminate this pole, a hybrid control structure is proposed. Here the control input is composed of two parts: analog and digital. The analog input simply represents the velocity (or the integral of acceleration) feedback; and the digital controller which uses only relative displacement signal, is then obtained to achieve the desired closed-loop transfer function. The stability analysis indicates that the controller transfer function is stable for typical values of sampling period. In the second approach, the aforementioned hybrid control structure is again used. First, an analog controller transfer function corresponding to relative displacement feedback is obtained to achieve the transmissibility as 1/(tauS+1)(exp 2). Then the transfer function for the digital control input is obtained by discretizing this analog controller transfer function via bilinear

  18. Distributed and recoverable digital control system

    NASA Technical Reports Server (NTRS)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)

    2010-01-01

    A real-time multi-tasking digital control system with rapid recovery capability is disclosed. The control system includes a plurality of computing units comprising a plurality of redundant processing units, with each of the processing units configured to generate one or more redundant control commands. One or more internal monitors are employed for detecting data errors in the control commands. One or more recovery triggers are provided for initiating rapid recovery of a processing unit if data errors are detected. The control system also includes a plurality of actuator control units each in operative communication with the computing units. The actuator control units are configured to initiate a rapid recovery if data errors are detected in one or more of the processing units. A plurality of smart actuators communicates with the actuator control units, and a plurality of redundant sensors communicates with the computing units.

  19. Improving the cost-effectiveness, trade and safety of biological control for agricultural insect pests using nuclear techniques

    Technology Transfer Automated Retrieval System (TEKTRAN)

    If appropriately applied, biological control offers one of the most promising, environmentally sound, and sustainable control tactics for arthropod pests and weeds for application as part of an integrated pest management (IPM) approach. Public support for biological control as one of the preferred m...

  20. Cost-effectiveness of a nurse-led internet-based vascular risk factor management programme: economic evaluation alongside a randomised controlled clinical trial

    PubMed Central

    Greving, J P; Kaasjager, H A H; Vernooij, J W P; Hovens, M M C; Wierdsma, J; Grandjean, H M H; van der Graaf, Y; de Wit, G A; Visseren, F L J

    2015-01-01

    Objective To assess the cost-effectiveness of an internet-based, nurse-led vascular risk factor management programme in addition to usual care compared with usual care alone in patients with a clinical manifestation of a vascular disease. Design Cost-effectiveness analysis alongside a randomised controlled trial (the Internet-based vascular Risk factor Intervention and Self-management (IRIS) study). Setting Multicentre trial in a secondary and tertiary healthcare setting. Participants 330 patients with a recent clinical manifestation of atherosclerosis in the coronary, cerebral, or peripheral arteries and with ≥2 treatable vascular risk factors not at goal. Intervention The intervention consisted of a personalised website with an overview and actual status of patients’ vascular risk factors, and mail communication with a nurse practitioner via the website for 12 months. The intervention combined self-management support, monitoring of disease control and pharmacotherapy. Main outcome measures Societal costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness. Results Patients experienced equal health benefits, that is, 0.86 vs 0.85 QALY (intervention vs usual care) at 1 year. Adjusting for baseline differences, the incremental QALY difference was −0.014 (95% CI −0.034 to 0.007). The intervention was associated with lower total costs (€4859 vs €5078, difference €219, 95% CI −€2301 to €1825). The probability that the intervention is cost-effective at a threshold value of €20 000/QALY, is 65%. At mean annual cost of €220 per patient, the intervention is relatively cheap. Conclusions An internet-based, nurse-led intervention in addition to usual care to improve vascular risk factors in patients with a clinical manifestation of a vascular disease does not result in a QALY gain at 1 year, but has a small effect on vascular risk factors and is associated with lower costs. Trial registration number NCT00785031. PMID

  1. A Cost-Effectiveness Analysis of a Program to Control Rheumatic Fever and Rheumatic Heart Disease in Pinar del Rio, Cuba

    PubMed Central

    Watkins, David A.; Mvundura, Mercy; Nordet, Porfirio; Mayosi, Bongani M.

    2015-01-01

    Background Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) persist in many low- and middle-income countries. To date, the cost-effectiveness of population-based, combined primary and secondary prevention strategies has not been assessed. In the Pinar del Rio province of Cuba, a comprehensive ARF/RHD control program was undertaken over 1986 – 1996. The present study analyzes the cost-effectiveness of this Cuban program. Methods and Findings We developed a decision tree model based on the natural history of ARF/RHD, comparing the costs and effectiveness of the 10-year Cuban program to a “do nothing” approach. Our population of interest was the cohort of children aged 5 – 24 years resident in Pinar del Rio in 1986. We assessed costs and health outcomes over a lifetime horizon, and we took the healthcare system perspective on costs but did not apply a discount rate. We used epidemiologic, clinical, and direct medical cost inputs that were previously collected for publications on the Cuban program. We estimated health gains as disability-adjusted life years (DALYs) averted using standard approaches developed for the Global Burden of Disease studies. Cost-effectiveness acceptability thresholds were defined by one and three times per capita gross domestic product per DALY averted. We also conducted an uncertainty analysis using Monte Carlo simulations and several scenario analyses exploring the impact of alternative assumptions about the program’s effects and costs. We found that, compared to doing nothing, the Cuban program averted 5051 DALYs (1844 per 100,000 school-aged children) and saved $7,848,590 (2010 USD) despite a total program cost of $202,890 over 10 years. In the scenario analyses, the program remained cost saving when a lower level of effectiveness and a reduction in averted years of life lost were assumed. In a worst-case scenario including 20-fold higher costs, the program still had a 100% of being cost-effective and an 85% chance

  2. Cost-effectiveness of minimal interventional procedures for chronic mechanical low back pain: design of four randomised controlled trials with an economic evaluation

    PubMed Central

    2012-01-01

    Background Minimal interventional procedures are frequently applied in patients with mechanical low back pain which is defined as pain presumably resulting from single sources: facet, disc, sacroiliac joint or a combination of these. Usually, these minimal interventional procedures are an integral part of a multidisciplinary pain programme. A recent systematic review issued by the Dutch Health Insurance Council showed that the effectiveness of these procedures for the total group of patients with chronic low back pain is yet unclear and cost-effectiveness unknown. The aim of the study is to evaluate whether a multidisciplinary pain programme with minimal interventional procedures is cost-effective compared to the multidisciplinary pain programme alone for patients with chronic mechanical low back pain who did not respond to conservative primary care and were referred to a pain clinic. Methods All patients with chronic low back pain who are referred to one of the 13 participating pain clinics will be asked to participate in an observational study. Patients with a suspected diagnosis of facet, disc or sacroiliac joint problems will receive a diagnostic block to confirm this diagnosis. If confirmed, they will be asked to participate in a Randomized Controlled Trial (RCT). For each single source a separate RCT will be conducted. Patients with a combination of facet, disc or sacroiliac joint problems will be invited for participation in a RCT as well. An economic evaluation from a societal perspective will be performed alongside these four RCTs. Patients will complete questionnaires at baseline, 3 and 6 weeks, 3, 6, 9 and 12 months after start of the treatment. Costs will be collected using self-completed cost questionnaires. Discussion No trials are yet available which have evaluated the cost-effectiveness of minimal interventional procedures in patients with chronic mechanical low back pain, which emphasizes the importance of this study. Trial registration number

  3. Evaluation of the Cost-Effectiveness of Pyramidal, Modified Pyramidal and Monoscreen Traps for the Control of the Tsetse Fly, Glossina fuscipes fuscipes, in Uganda

    PubMed Central

    Abila, P.P.; Okello-Onen, J.; Okoth, J.O.; Matete, G.O.; Wamwiri, F.; Politzar, H.

    2007-01-01

    Several trap designs have been used for sampling and control of the tsetse fly, Glossina fuscipes fuscipes, Newstead (Diptera: Glossinidae) based on preferences of individual researchers and program managers with little understanding of the comparative efficiency and cost-effectiveness of trap designs. This study was carried out to evaluate the cost-effectiveness of four commonly used trap designs: monoscreen, modified pyramidal and pyramidal, relative to the standard biconical trap. The study was performed under high tsetse challenge on Buvuma Island, Lake Victoria, Uganda, using a 4 × 4 Latin square design replicated 3 times, so as to separate the trap positions and day effects from the treatment effect. A total of 12 trap positions were tested over 4 days. The monoscreen trap caught significantly higher numbers of G. f. fuscipes (P<0.05) followed by biconical, modified pyramidal and pyramidal traps. Analysis of variance showed that treatment factor was a highly significant source of variation in the data. The index of increase in trap catches relative biconical were O.60 (pyramidal), 0.68 (modified pyramidal) and 1.25 (monoscreen). The monoscreen trap was cheaper (US$ 2.61) and required less material to construct than pyramidal trap (US$ 3.48), biconical and the modified pyramidal traps (US$ 4.06 each). Based on the number of flies caught per meter of material, the monoscreen trap proved to be the most cost-effective (232 flies/m) followed by the biconical trap (185 flies/m). The modified pyramidal and the pyramidal traps caught 112 and 125 flies/m, respectively. PMID:20345292

  4. Cost-effectiveness of microendoscopic discectomy versus conventional open discectomy in the treatment of lumbar disc herniation: a prospective randomised controlled trial [ISRCTN51857546

    PubMed Central

    Arts, Mark P; Peul, Wilco C; Brand, Ronald; Koes, Bart W; Thomeer, Ralph TWM

    2006-01-01

    Background Open discectomy is the standard surgical procedure in the treatment of patients with long-lasting sciatica caused by lumbar disc herniation. Minimally invasive approaches such as microendoscopic discectomy have gained attention in recent years. Reduced tissue trauma allows early ambulation, short hospital stay and quick resumption of daily activities. A comparative cost-effectiveness study has not been performed yet. We present the design of a randomised controlled trial on cost-effectiveness of microendoscopic discectomy versus conventional open discectomy in patients with lumbar disc herniation. Methods/Design Patients (age 18–70 years) presenting with sciatica due to lumbar disc herniation lasting more than 6–8 weeks are included. Patients with disc herniation larger than 1/3 of the spinal canal diameter, or disc herniation less than 1/3 of the spinal canal diameter with concomitant lateral recess stenosis or sequestration, are eliglible for participation. Randomisation into microendoscopic discectomy or conventional unilateral transflaval discectomy will take place in the operating room after induction of anesthesia. The length of skin incision is equal in both groups. The primary outcome measure is the functional assessment of the patient, measured by the Roland Disability Questionnaire for Sciatica, at 8 weeks and 1 year after surgery. We will also evaluate several other outcome parameters, including perceived recovery, leg and back pain, incidence of re-operations, complications, serum creatine kinase, quality of life, medical consumption, absenteeism and costs. The study is a randomised prospective multi-institutional trial, in which two surgical techniques are compared in a parallel group design. Patients and research nurses are kept blinded of the allocated treatment during the follow-up period of 2 years. Discussion Currently, open discectomy is the golden standard in the surgical treatment of lumbar disc herniation. Whether

  5. Digital adaptive control laws for VTOL aircraft

    NASA Technical Reports Server (NTRS)

    Hartmann, G. L.; Stein, G.

    1979-01-01

    Honeywell has designed a digital self-adaptive flight control system for flight test in the VALT Research Aircraft (a modified CH-47). The final design resulted from a comparison of two different adaptive concepts: one based on explicit parameter estimates from a real-time maximum likelihood estimation algorithm and the other based on an implicit model reference adaptive system. The two designs are compared on the basis of performance and complexity.

  6. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman

    2003-12-01

    During the second reporting period, the project team focused on identifying promising technologies that can then be used to monitor and control emissions from E&P engines. These technologies include control and monitoring technologies and in most cases can be used to monitor engine performance as well as control and monitor engine emissions. The project team also identified three potential sources to receive a Cooper Ajax engine that is approximately 100 bhp. The goal is to have this engine delivered to the project team by the end of the calendar year 2003. This will then allow the team to prepare the engine for testing at Ricardo in early 2004.

  7. Obsessive Compulsive Treatment Efficacy Trial (OCTET) comparing the clinical and cost effectiveness of self-managed therapies: study protocol for a randomised controlled trial

    PubMed Central

    2014-01-01

    Background UK National Institute of Health and Clinical Excellence guidelines for obsessive compulsive disorder (OCD) specify recommendations for the treatment and management of OCD using a stepped care approach. Steps three to six of this model recommend treatment options for people with OCD that range from low-intensity guided self-help (GSH) to more intensive psychological and pharmacological interventions. Cognitive behavioural therapy (CBT), including exposure and response prevention, is the recommended psychological treatment. However, whilst there is some preliminary evidence that self-managed therapy packages for OCD can be effective, a more robust evidence base of their clinical and cost effectiveness and acceptability is required. Methods/Design Our proposed study will test two different self-help treatments for OCD: 1) computerised CBT (cCBT) using OCFighter, an internet-delivered OCD treatment package; and 2) GSH using a book. Both treatments will be accompanied by email or telephone support from a mental health professional. We will evaluate the effectiveness, cost and patient and health professional acceptability of the treatments. Discussion This study will provide more robust evidence of efficacy, cost effectiveness and acceptability of self-help treatments for OCD. If cCBT and/or GSH prove effective, it will provide additional, more accessible treatment options for people with OCD. Trial registration Current Controlled Trials: ISRCTN73535163. Date of registration: 5 April 2011 PMID:25011730

  8. Autism Spectrum Social Stories In Schools Trial (ASSSIST): study protocol for a feasibility randomised controlled trial analysing clinical and cost-effectiveness of Social Stories in mainstream schools

    PubMed Central

    Wright, Barry; Marshall, David; Collingridge Moore, Danielle; Ainsworth, Hannah; Hackney, Lisa; Adamson, Joy; Ali, Shehzad; Allgar, Victoria; Cook, Liz; Dyson, Lisa; Littlewood, Elizabeth; Hargate, Rebecca; McLaren, Anne; McMillan, Dean; Trépel, Dominic; Whitehead, Jo; Williams, Chris

    2014-01-01

    Introduction Current evidence suggests that Social Stories can be effective in tackling problem behaviours exhibited by children with autism spectrum disorder. Exploring the meaning of behaviour from a child's perspective allows stories to provide social information that is tailored to their needs. Case reports in children with autism have suggested that these stories can lead to a number of benefits including improvements in social interactions and choice making in educational settings. Methods and analysis The feasibility of clinical and cost-effectiveness of a Social Stories toolkit will be assessed using a randomised control framework. Participants (n=50) will be randomised to either the Social Stories intervention or a comparator group where they will be read standard stories for an equivalent amount of time. Statistics will be calculated for recruitment rates, follow-up rates and attrition. Economic analysis will determine appropriate measures of generic health and resource use categories for cost-effectiveness analysis. Qualitative analysis will ascertain information on perceptions about the feasibility and acceptability of the intervention. Ethics and dissemination National Health Service Ethics Approval (NHS; ref 11/YH/0340) for the trial protocol has been obtained along with NHS Research and Development permission from Leeds and York Partnership NHS Foundation Trust. All adverse events will be closely monitored, documented and reported to the study Data Monitoring Ethics Committee. At least one article in a peer reviewed journal will be published and research findings presented at relevant conferences. Trial registration number ISRCTN96286707. PMID:25009139

  9. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Keith Hohn; Sarah R. Nuss-Warren

    2011-08-31

    This final report describes a project intended to identify, develop, test, and commercialize emissions control and monitoring technologies that can be implemented by E&P operators to significantly lower their cost of environmental compliance and expedite project permitting. Technologies were installed and tested in controlled laboratory situations and then installed and tested on field engines based on the recommendations of an industry-based steering committee, analysis of installed horsepower, analysis of available emissions control and monitoring technologies, and review of technology and market gaps. The industry-recognized solution for lean-burn engines, a low-emissions-retrofit including increased airflow and pre-combustion chambers, was found to successfully control engine emissions of oxides of nitrogen (NO{sub X}) and carbon monoxide (CO). However, the standard non-selective catalytic reduction (NSCR) system recognized by the industry was found to be unable to consistently control both NO{sub X} and CO emissions. The standard NSCR system was observed to produce emissions levels that changed dramatically on a day-to-day or even hour-to-hour basis. Because difficulties with this system seemed to be the result of exhaust gas oxygen (EGO) sensors that produced identical output for very different exhaust gas conditions, models were developed to describe the behavior of the EGO sensor and an alternative, the universal exhaust gas oxygen (UEGO) sensor. Meanwhile, an integrated NSCR system using an advanced, signal-conditioned UEGO sensor was tested and found to control both NO{sub X} and CO emissions. In conjunction with this project, advanced monitoring technologies, such as Ion Sense, and improved sensors for emissions control, such as the AFM1000+ have been developed and commercialized.

  10. Digital control algorithms for microgravity isolation systems

    NASA Technical Reports Server (NTRS)

    Sinha, A.; Wang, Y.-P.

    1993-01-01

    New digital control algorithms have been developed to achieve the desired transmissibility function for a microgravity isolation system. Two approaches have been presented for the controller design in the context of a single degree of freedom system for which an attractive electromagnet is used as the actuator. The relative displacement and the absolute acceleration of the mass have been used as feedback signals. The results from numerical studies are presented. It has been found that the resulting transmissibility is quite close to the desired function. Also, the maximum coil currents required by new algorithms are smaller than the maximum current demanded by the previously proposed lead/lag method.

  11. Digital control system for space structural dampers

    NASA Technical Reports Server (NTRS)

    Haviland, J. K.

    1984-01-01

    A recently developed concept for a damper was improved by adding a small taper to the proof-mass, and using a proximeter to determine position. Also, an experimental damper was built using a three-inch stroke in place of the standard one-inch stroke. The analog controller initially used was replaced by an independent digital controller slaved to a TRS-80 Model I computer, which also serves as a highly effective, low-cost development system. An overall system concept for the use of proof-mass dampers is presented.

  12. The digital control of anaesthetic gas flow.

    PubMed

    Boaden, R W; Hutton, P

    1986-04-01

    The theory and construction of a prototype digital gas flow controller are described. Using eight preset needle valves, it has the ability to deliver any flow from 50 to 12750 ml/minute in steps of 50 ml/minute. Under given conditions, the accuracy of this device is very high and its variation in performance with pipeline supply pressures is quantified. The required flow is requested from a BBC 'B' microcomputer which is interfaced with the equipment via a program written in Basic and the 1MHz bus port. The possible uses and potential of a microcomputer-controlled flow regulator in anaesthesia and intensive care are discussed. PMID:2939766

  13. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman; Allen J. Adriani

    2004-01-01

    For the period of the 8th reporting period high-impact control technologies were identified during the meeting at Cooper in Oklahoma City. The technologies that were identified will be tested on the Ajax DP-115 engine and are capable of being widely utilized by the E&P industry. Two major areas where engine controls and ignition systems, but still included were other alternatives to reduce emissions. The most exhilarating item for this quarter was when Ajax engine was delivered to the test bed at the NGML.

  14. Digitally controlled twelve-pulse firing generator

    SciTech Connect

    Berde, D.; Ferrara, A.A.

    1981-01-01

    Control System Studies for the Tokamak Fusion Test Reactor (TFTR) indicate that accurate thyristor firing in the AC-to-DC conversion system is required in order to achieve good regulation of the various field currents. Rapid update and exact firing angle control are required to avoid instabilities, large eddy currents, or parasitic oscillations. The Prototype Firing Generator was designed to satisfy these requirements. To achieve the required /plus or minus/0.77/degree/firing accuracy, a three-phase-locked loop reference was designed; otherwise, the Firing Generator employs digital circuitry. The unit, housed in a standard CAMAC crate, operates under microcomputer control. Functions are performed under program control, which resides in nonvolatile read-only memory. Communication with CICADA control system is provided via an 11-bit parallel interface.

  15. Deterministic digital WDM LAN for controlled configurations

    NASA Astrophysics Data System (ADS)

    Mazurowski, John

    2013-09-01

    This work introduces the concept of a digital Wavelength Division Multiplexed (WDM) network for small avionic and space platforms. For packaging and heat transfer efficiency, all optical wavelength sources occupy a common location. Addressable wavelengths are allocated to each receiver, which may be reached by selection or tuning of a transmitter wavelength. Individual delays may be applied to assure synchronization at each receiver. The output of each individual source wavelength is pre-modulated with a clock signal. Signal modulation is applied by passing or rejecting the clock signals. Due to the simplicity of the modulation, the control plane functions can be merged with the data plane functions. Although the concept is based on a single data rate, the digital WDM LAN concept can possibly be extended to process packet and analog payloads.

  16. Evaluation of the effectiveness and cost-effectiveness of Families for Health V2 for the treatment of childhood obesity: study protocol for a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Effective programs to help children manage their weight are required. Families for Health focuses on a parenting approach, designed to help parents develop their parenting skills to support lifestyle change within the family. Families for Health V1 showed sustained reductions in overweight after 2 years in a pilot evaluation, but lacks a randomized controlled trial (RCT) evidence base. Methods/design This is a multi-center, investigator-blind RCT, with parallel economic evaluation, with a 12-month follow-up. The trial will recruit 120 families with at least one child aged 6 to 11 years who is overweight (≥91st centile BMI) or obese (≥98th centile BMI) from three localities and assigned randomly to Families for Health V2 (60 families) or the usual care control (60 families) groups. Randomization will be stratified by locality (Coventry, Warwickshire, Wolverhampton). Families for Health V2 is a family-based intervention run in a community venue. Parents/carers and children attend parallel groups for 2.5 hours weekly for 10 weeks. The usual care arm will be the usual support provided within each NHS locality. A mixed-methods evaluation will be carried out. Child and parent participants will be assessed at home visits at baseline, 3-month (post-treatment) and 12-month follow-up. The primary outcome measure is the change in the children’s BMI z-scores at 12 months from the baseline. Secondary outcome measures include changes in the children’s waist circumference, percentage body fat, physical activity, fruit/vegetable consumption and quality of life. The parents’ BMI and mental well-being, family eating/activity, parent–child relationships and parenting style will also be assessed. Economic components will encompass the measurement and valuation of service utilization, including the costs of running Families for Health and usual care, and the EuroQol EQ-5D health outcomes. Cost-effectiveness will be expressed in terms of incremental cost per

  17. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman; Allen J. Adriani

    2005-04-01

    During the eighth reporting period, high-impact monitoring and control technologies were identified during a series of meetings at Ajax/Cooper in Oklahoma City. Many of the technologies that were identified will be tested on the Ajax DP-115 engine and are capable of being widely utilized by the E&P industry. Two major areas were engine controls and ignition systems but still included other alternatives to reduce emissions. Another major advance was the completion of setting the Ajax DP-115 engine. This includes anchoring and leveling the engine. Shortly after the engine was prepared, all the necessary utilities were installed. Once the utilities were installed the engine was successfully operated over its normal operating range at the end of the reporting period.

  18. Cost-effectiveness of social marketing of insecticide-treated nets for malaria control in the United Republic of Tanzania.

    PubMed Central

    Hanson, Kara; Kikumbih, Nassor; Armstrong Schellenberg, Joanna; Mponda, Haji; Nathan, Rose; Lake, Sally; Mills, Anne; Tanner, Marcel; Lengeler, Christian

    2003-01-01

    OBJECTIVE: To assess the costs and consequences of a social marketing approach to malaria control in children by means of insecticide-treated nets in two rural districts of the United Republic of Tanzania, compared with no net use. METHODS: Project cost data were collected prospectively from accounting records. Community effectiveness was estimated on the basis of a nested case-control study and a cross-sectional cluster sample survey. FINDINGS: The social marketing approach to the distribution of insecticide-treated nets was estimated to cost 1560 US dollars per death averted and 57 US dollars per disability-adjusted life year averted. These figures fell to 1018 US dollars and 37 US dollars, respectively, when the costs and consequences of untreated nets were taken into account. CONCLUSION: The social marketing of insecticide-treated nets is an attractive intervention for preventing childhood deaths from malaria. PMID:12764493

  19. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman; Allen Adriani

    2004-04-01

    During the fifth reporting period, the main goal for the team was to focus on collecting data to develop Oxygen Sensor Recording System (OSRS) parametric relationships for several rich-burn engines. An air/fuel ratio controller was intergraded with an O{sub 2} sensor. With the use of an Alternative Continuous Emissions Monitoring System (ACEMS) provided by Eastern Municipal Water District (EMWD), the performance will be observed during normal operation.

  20. Efficient control of air pollution through plants, a cost-effective alternative: studies on Dalbergia sissoo Roxb.

    PubMed

    Kapoor, C S; Bamniya, B R; Kapoor, K

    2013-09-01

    Plants can be used as both passive biomonitors and biomitigators in urban and industrial environments to indicate the environmental quality and to ameliorate pollution level in a locality. Many studies reveal that plants are negatively affected by the ambient levels of air pollutants. The present study was conducted to evaluate the impact of air pollution on comparative basis with reference to changes in photosynthetic pigments, plant height, leaves, as well as, biochemical parameters of plants of different sites around Udaipur city receiving varying levels of pollution load. The investigated tree species Dalbergia sissoo Roxb. (Family: Fabaceae) exhibited a reduction in various physiological and biochemical growth parameters that correspond with air pollution levels at different sites. The tree species growing in polluted and control areas were compared with respect to foliar dust load, leaf area, and chlorophyll and total carbohydrate and total protein concentration in the leaves. Our studies suggest that D. sissoo Roxb. can successfully be grown in an area for monitoring air pollution, where it is mild and droughts are common. It will prove as an ideal tree species to control pollution effectively beside acting as a shade tree and being a source of food for birds and animals. By plantation of D. sissoo Roxb., mitigative measure at the polluted sites to control generation of particulate matter and the air quality required can be ensured. Our results also confirm that industrial and vehicular air pollution level in Udaipur city is shifting beyond limits. PMID:23423551

  1. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Greg Beshouri; Kirby S. Chapman; Jim McCarthy; Sarah R. Nuss-Warren; Mike Whelan

    2006-03-01

    This quarterly report re-evaluates current market objectives in the exploration and production industry, discusses continuing progress in testing that evaluates emission control technologies applied to a two-stroke cycle natural gas-fueled engine, and presents a scheme for enacting remote monitoring and control of engines during upcoming field tests. The examination of current market objectives takes into account technological developments and changing expectations for environmental permitting which may have occurred over the last year. This demonstrates that the continuing work in controlled testing and toward field testing is on track Market pressures currently affecting the gas exploration and production industry are shown to include a push for increased production, as well as an increasing cost for environmental compliance. This cost includes the direct cost of adding control technologies to field engines as well as the indirect cost of difficulty obtaining permits. Environmental regulations continue to require lower emissions targets, and some groups of engines which had not previously been regulated will be required to obtain permits in the future. While the focus remains on NOx and CO, some permits require reporting of additional emissions chemicals. Continuing work in controlled testing uses a one cylinder Ajax DP-115 (a 13.25 in bore x 16 in stroke, 360 rpm engine) to assess a sequential analysis and evaluation of a series of engine upgrades. As with most of the engines used in the natural gas industry, the Ajax engine is a mature engine with widespread usage throughout the gas gathering industry. The end point is an assessment of these technologies that assigns a cost per unit reduction in NOx emissions. Technologies including one pre-combustion chamber, in-cylinder sensors, the means to adjust the air-to-fuel ratio, and modification of the air filter housing have been evaluated in previous reports. Current work focuses on final preparations for testing

  2. Integrated modelling of cost-effective siting and operation of flow-control infrastructure for river ecosystem conservation

    NASA Astrophysics Data System (ADS)

    Higgins, A. J.; Bryan, B. A.; Overton, I. C.; Holland, K.; Lester, R. E.; King, D.; Nolan, M.; Connor, J. D.

    2011-05-01

    Wetland and floodplain ecosystems along many regulated rivers are highly stressed, primarily due to a lack of environmental flows of appropriate magnitude, frequency, duration, and timing to support ecological functions. In the absence of increased environmental flows, the ecological health of river ecosystems can be enhanced by the operation of existing and new flow-control infrastructure (weirs and regulators) to return more natural environmental flow regimes to specific areas. However, determining the optimal investment and operation strategies over time is a complex task due to several factors including the multiple environmental values attached to wetlands, spatial and temporal heterogeneity and dependencies, nonlinearity, and time-dependent decisions. This makes for a very large number of decision variables over a long planning horizon. The focus of this paper is the development of a nonlinear integer programming model that accommodates these complexities. The mathematical objective aims to return the natural flow regime of key components of river ecosystems in terms of flood timing, flood duration, and interflood period. We applied a 2-stage recursive heuristic using tabu search to solve the model and tested it on the entire South Australian River Murray floodplain. We conclude that modern meta-heuristics can be used to solve the very complex nonlinear problems with spatial and temporal dependencies typical of environmental flow allocation in regulated river ecosystems. The model has been used to inform the investment in, and operation of, flow-control infrastructure in the South Australian River Murray.

  3. An intervention program with the aim to improve and maintain work productivity for workers with rheumatoid arthritis: design of a randomized controlled trial and cost-effectiveness study

    PubMed Central

    2012-01-01

    Background Workers with rheumatoid arthritis (RA) often experience restrictions in functioning at work and participation in employment. Strategies to maintain work productivity exist, but these interventions do not involve the actual workplace. Therefore the aim of this study is to investigate the (cost)effectiveness of an intervention program at the workplace on work productivity for workers with RA. Methods/design This study is a randomized controlled trial (RCT) in specialized rheumatology treatment centers in or near Amsterdam, the Netherlands. Randomisation to either the control or the intervention group is performed at patient level. Both groups will receive care as usual by the rheumatologist, and patients in the intervention group will also take part in the intervention program. The intervention program consists of two components; integrated care, including a participatory workplace intervention. Integrated care involves a clinical occupational physician, who will act as care manager, to coordinate the care. The care manager has an intermediate role between clinical and occupational care. The participatory workplace intervention will be guided by an occupational therapist, and involves problem solving by the patient and the patients’ supervisor. The aim of the workplace intervention is to achieve consensus between patient and supervisor concerning feasible solutions for the obstacles for functioning at work. Data collection will take place at baseline and after 6 and 12 months by means of a questionnaire. The primary outcome measure is work productivity, measured by hours lost from work due to presenteeism. Secondary outcome measures include sick leave, quality of life, pain and fatigue. Cost-effectiveness of the intervention program will be evaluated from the societal perspective. Discussion Usual care of primary and outpatient health services is not aimed at improving work productivity. Therefore it is desirable to develop interventions aimed at

  4. Efficacy and cost-effectiveness of a web-based and mobile stress-management intervention for employees: design of a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Work-related stress is associated with a variety of mental and emotional problems and can lead to substantial economic costs due to lost productivity, absenteeism or the inability to work. There is a considerable amount of evidence on the effectiveness of traditional face-to-face stress-management interventions for employees; however, they are often costly, time-consuming, and characterized by a high access threshold. Web-based interventions may overcome some of these problems yet the evidence in this field is scarce. This paper describes the protocol for a study that will examine the efficacy and cost-effectiveness of a web-based guided stress-management training which is based on problem solving and emotion regulation and aimed at reducing stress in adult employees. Methods The study will target stressed employees aged 18 and older. A randomized controlled trial (RCT) design will be applied. Based on a power calculation of d=.35 (1-β of 80%, α = .05), 264 participants will be recruited and randomly assigned to either the intervention group or a six-month waitlist control group. Inclusion criteria include an elevated stress level (Cohen’s Perceived Stress Scale-10 ≥ 22) and current employment. Exclusion criteria include risk of suicide or previously diagnosed psychosis or dissociative symptoms. The primary outcome will be perceived stress, and secondary outcomes include depression and anxiety. Data will be collected at baseline and seven weeks and six months after randomization. An extended follow up at 12 months is planned for the intervention group. Moreover, a cost-effectiveness analysis will be conducted from a societal perspective and will include both direct and indirect health care costs. Data will be analyzed on an intention-to-treat basis and per protocol. Discussion The substantial negative consequences of work-related stress emphasize the necessity for effective stress-management trainings. If the proposed internet intervention proves

  5. Technical status report development of lime based in-duct scrubbing - A cost effective SO/sub 2/ control technology

    SciTech Connect

    Shilling, N.Z.; Samuel, E.A.; Pennline, H.

    1986-04-01

    Lime Based In-Duct Scrubbing (LIBIDS) was one of the candidate technologies receiving contract awards for pilot demonstration by the U.S. Department of Energy under the Acid Rain Precurser program. The concept as developed by General Electric utilizes rotary atomization of lime slurry directly within flue gas carrying ductwork to remove SO/sub 2/. This promises to be a very low capital cost method of SO/sub 2/ control with capital plus levelized operating cost estimated to be $364/KW. Several significant technical milestones have been passed relative to proof of principle and ultimate commercialization. Based on positive results from a laboratory and supporting analytical work, a detailed engineering design has begun for a pilot plant.

  6. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman

    2004-01-01

    During the fourth reporting period, the project team investigated the Non-Selective Catalytic Reduction technologies that are in use on rich-burn four-stroke cycle engines. Several engines were instrumented and data collected to obtain a rich set of engine emissions and performance data. During the data collection, the performance of the catalyst under a variety of operating conditions was measured. This information will be necessary to specify a set of sensors that can then be used to reliably implement NSCRs as plausible technologies to reduce NOx emissions for four-stroke cycle engines used in the E&P industry. A complete summary all the technologies investigated to data is included in the report. For each technology, the summary includes a description of the process, the emission reduction that is to be expected, information on the cost of the technology, development status, practical considerations, compatibility with other air pollutant control technologies, and any references used to obtain the information.

  7. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman

    2005-10-01

    This quarterly report discusses the results from a testing phase of the project that evaluates emission control technologies applied to a two-stroke cycle natural gas-fueled engine. In this phase, a one cylinder Ajax DP-115 (a 13.25 in bore x 16 in stroke, 360 rpm engine) is used to assess a sequential analysis and evaluation of a series of engine upgrades. As with most of the engines used in the natural gas industry, the Ajax engine is a mature engine with widespread usage throughout gas gathering industry. The end point is an assessment of these technologies that assigns a cost per unit reduction in NO{sub x} emissions. This report describes potential emission reduction technologies followed by a battery of tests that demonstrate synergies between some of the more promising technologies. While the end-goal is a closed loop control, low cost NO{sub x} retrofit package, additional work remains. The battery of tests include pre-combustion chambers, in-cylinder sensors, the means to adjust the air-to-fuel ratio, and modification of the air filter housing. During several phases of the tests, the ignition timing also was varied to determine the optimal point for ignition timing. The results from these tests suggest that an optimum exists where fuel consumption is minimized along with NO{sub x} emissions. By using the Ajax DP-115 these tests are completed in a low-cost and efficient manner. The various technologies can be quickly exchanged with different hardware, and the cost to operate the engine is very inexpensive.

  8. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Sarah R. Nuss-Warren; Kirby S. Chapman

    2005-12-01

    This quarterly report discusses continuing work in the testing phase of the project that evaluates emission control technologies applied to a two-stroke cycle natural gas-fueled engine. In this phase, a one cylinder Ajax DP-115 (a 13.25 in bore x 16 in stroke, 360 rpm engine) is used to assess a sequential analysis and evaluation of a series of engine upgrades. As with most of the engines used in the natural gas industry, the Ajax engine is a mature engine with widespread usage throughout the gas gathering industry. The end point is an assessment of these technologies that assigns a cost per unit reduction in NO{sub x} emissions. This report describes potential emission reduction technologies, some of which have already been tested, and describes progress toward completing remaining tests to evaluate further synergies between some of the more promising technologies. While the end-goal is a closed-loop control system coupled with a low cost NO{sub x} retrofit package, additional work remains. Technologies including pre-combustion chambers, in-cylinder sensors, the means to adjust the air-to-fuel ratio, and modification of the air filter housing have been evaluated in previous reports. Current work focuses on preparing the test cell for tests using a 180 psig fuel valve. By using the Ajax DP-115 these tests are completed in a low-cost and efficient manner. The various technologies can be quickly exchanged with different hardware, and it is inexpensive to run the engine.

  9. Optimized exposure control in digital mammography

    NASA Astrophysics Data System (ADS)

    Shramchenko, Nataliya; Blin, Philippe; Mathey, Claude; Klausz, Remy

    2004-05-01

    A method for the determination of optimal operating points of digital mammography systems is described. The digital mammography equipment uses a flat panel detector and a bi-metal molybdenum/rhodium x-ray tube. An operating point is defined by the selection of the x-ray tube target material, x-ray filtration, kVp and detector entrance dose. Breast thickness and composition are estimated from a low dose pre-exposure, then used to index tables containing sets of operating points. The operating points are determined using a model of the image chain, which computes contrast to noise ratio (CNR) and average glandular dose (AGD) for all possible exposure conditions and breast thickness and composition combinations. The selected operating points are those which provide the required CNR for the lowest AGD. An AGD reduction of 30% to 50% can be achieved for comparable Image Quality, relative to current operating points. Resulting from the optimization process, the rhodium target is used in more than 75% of cases. Measurements of CNR and AGD have been performed on various tissue equivalent materials with good agreement between calculated and measured values. The proposed method provides full Image Quality benefit of digital mammography while minimizing dose to patients in a controlled and predictive way.

  10. Control of hair growth using long-pulsed alexandrite laser is an efficient and cost effective therapy for patients suffering from recurrent pilonidal disease.

    PubMed

    Khan, Muhammad Adil Abbas; Javed, Ammar Asrar; Govindan, Karthikeyan Srinivasan; Rafiq, Sadia; Thomas, Kay; Baker, Lynne; Kenealy, John

    2016-07-01

    Pilonidal sinus (PNS) and its surgical management have a profound impact on hospital resources in terms of finances and productive man-hours. Surgical treatment has been the mainstay of treatment of both acute and chronic pilonidal sinus but recurrence is common. The control of hair growth in the sinus region plays an important role in preventing recurrence. Here, we discuss our experience of treating 19 patients suffering from recurrent pilonidal sinus with laser depilation and its long-term cost effectiveness. This is a retrospective study on patients who had recurrence of pilonidal sinus following multiple surgical treatments. They were treated using long-pulsed alexandrite laser for depilation in the sinus area, an outpatient procedure. Their clinical characteristics and outcomes were then evaluated. There was a significant reduction in hair density after laser treatment (p < 0.001). The disease-free period after laser treatment was significantly longer than that one after surgical treatment (p < 0.001). The average cost of repeated surgical treatment per disease-free month was significantly higher than that of laser treatment (p < 0.001). Evidence suggests the role of natal cleft hair growth in the evolution of the pilonidal disease; therefore, control of hair growth should be considered as an adjunct to the initial treatment via surgery. Compared to surgical treatment of recurrences, laser depilation is an efficient and cost-effective method of preventing recurrence and reducing morbidity and loss of man-hours. We suggest that laser depilation of the pilonidal sinus should be funded by clinical commissioning groups. PMID:27003897

  11. Unconventional digital reactor control without conventional programming

    SciTech Connect

    Edwards, R.M.; Johns, R.M.; Kenney, S.J.

    1995-12-31

    Recent advances in simulation technology have resulted in the capability to design, test, and implement advanced control algorithms without the need for the labor-intensive effort of writing and debugging of computer programs. This technology has been adopted for a program of experimental development of power reactor control, which is jointly sponsored by the National Science Foundation and the Electric Power Research Institute. The experimental reactor control test bed utilizes the General Atomic Mark III TRIGA reactor at the Penn State Breazeale reactor facility. Control experiments are conducted within the movable experiment technical specifications of the TRIGA. A digital controller with an experimental control algorithm is interfaced to a secondary control rod (SCR). The new technology presented in this paper utilizes a UNIX network-compatible microprocessor-based controller operating under the Wind River Systems VxWorks real-time operating system. The controller interfaces with the Math-works MATLAB/SIMULINK development environment and Real-Time Innovations 8 monitoring software remotely operated on a SPARC workstation.

  12. Ion propulsion cost effectivity

    NASA Technical Reports Server (NTRS)

    Zafran, S.; Biess, J. J.

    1978-01-01

    Ion propulsion modules employing 8-cm thrusters and 30-cm thrusters were studied for Multimission Modular Spacecraft (MMS) applications. Recurring and nonrecurring cost elements were generated for these modules. As a result, ion propulsion cost drivers were identified to be Shuttle charges, solar array, power processing, and thruster costs. Cost effective design approaches included short length module configurations, array power sharing, operation at reduced thruster input power, simplified power processing units, and power processor output switching. The MMS mission model employed indicated that nonrecurring costs have to be shared with other programs unless the mission model grows. Extended performance missions exhibited the greatest benefits when compared with monopropellant hydrazine propulsion.

  13. Cost-Effective Reciprocating Engine Emissions Control and Monitoring for E&P Field and Gathering Engines

    SciTech Connect

    Kirby S. Chapman; Sarah R. Nuss-Warren

    2006-07-01

    Continuing work in controlled testing uses a one cylinder Ajax DP-115 (a 13.25 in bore x 16 in stroke, 360 rpm engine) to assess a sequential analysis and evaluation of a series of engine upgrades. As with most of the engines used in the natural gas industry, the Ajax engine is a mature engine with widespread usage throughout the gas gathering industry. The end point is an assessment of these technologies that assigns a cost per unit reduction in NOX emissions. Technologies including one pre-combustion chamber, in-cylinder sensors, the means to adjust the air-to-fuel ratio, and modification of the air filter housing have been evaluated in previous reports. Current work focuses on final preparations for testing pre-combustion chambers with different characteristics and using mid-to-high-pressure fuel valves and initial runs of these tests. By using the Ajax DP-115 these tests are completed in a low-cost and efficient manner. The various technologies can be quickly exchanged with different hardware, and it is inexpensive to run the engine. Progress in moving toward field testing is discussed, and changes to the first planned field test are presented. Although changes have been made to the previous plan, it is expected that several new sites will be selected soon. Field tests will begin in the next quarter.

  14. Optimal digital control of multirate systems

    NASA Technical Reports Server (NTRS)

    Amit, N.; Powell, J. D.

    1981-01-01

    Many digitally controlled aerospace systems have widely separated time constants and thus can benefit from the use of two or more sample rates. In this paper, the analysis and synthesis of multirate systems is accomplished by creating an equivalent single rate system and applying existing techniques. The optimal steady state solution of the single rate system is obtained by eigenvector decomposition and then used to compute the periodic solution to the Riccati equation of the original multirate system. An example shows when multirate analysis is necessary and the penalty of various levels of approximations to the exact multirate solution.

  15. Lessons learned in digital upgrade projects digital control system implementation at US nuclear power stations

    SciTech Connect

    Kelley, S.; Bolian, T. W.

    2006-07-01

    AREVA NP has gained significant experience during the past five years in digital upgrades at operating nuclear power stations in the US. Plants are seeking modernization with digital technology to address obsolescence, spare parts availability, vendor support, increasing age-related failures and diminished reliability. New systems offer improved reliability and functionality, and decreased maintenance requirements. Significant lessons learned have been identified relating to the areas of licensing, equipment qualification, software quality assurance and other topics specific to digital controls. Digital control systems have been installed in non safety-related control applications at many utilities within the last 15 years. There have also been a few replacements of small safety-related systems with digital technology. Digital control systems are proving to be reliable, accurate, and easy to maintain. Digital technology is gaining acceptance and momentum with both utilities and regulatory agencies based upon the successes of these installations. Also, new plants are being designed with integrated digital control systems. To support plant life extension and address obsolescence of critical components, utilities are beginning to install digital technology for primary safety-system replacement. AREVA NP analyzed operating experience and lessons learned from its own digital upgrade projects as well as industry-wide experience to identify key issues that should be considered when implementing digital controls in nuclear power stations.

  16. Clinical effectiveness and cost-effectiveness of body psychotherapy in the treatment of negative symptoms of schizophrenia: a multicentre randomised controlled trial.

    PubMed Central

    Priebe, Stefan; Savill, Mark; Wykes, Til; Bentall, Richard; Lauber, Christoph; Reininghaus, Ulrich; McCrone, Paul; Mosweu, Iris; Bremner, Stephen; Eldridge, Sandra; Röhricht, Frank

    2016-01-01

    BACKGROUND: The negative symptoms of schizophrenia significantly impact on quality of life and social functioning, and current treatment options are limited. In this study the clinical effectiveness and cost-effectiveness of group body psychotherapy as a treatment for negative symptoms were compared with an active control. DESIGN: A parallel-arm, multisite randomised controlled trial. Randomisation was conducted independently of the research team, using a 1 : 1 computer-generated sequence. Assessors and statisticians were blinded to treatment allocation. Analysis was conducted following the intention-to-treat principle. In the cost-effectiveness analysis, a health and social care perspective was adopted. PARTICIPANTS: ELIGIBILITY CRITERIA: age 18-65 years; diagnosis of schizophrenia with symptoms present at > 6 months; score of ≥ 18 on Positive and Negative Syndrome Scale (PANSS) negative symptoms subscale; no change in medication type in past 6 weeks; willingness to participate; ability to give informed consent; and community outpatient. EXCLUSION CRITERIA: inability to participate in the groups and insufficient command of English. SETTINGS: Participants were recruited from NHS mental health community services in five different Trusts. All groups took place in local community spaces. INTERVENTIONS: Control intervention: a 10-week, 90-minute, 20-session group beginners' Pilates class, run by a qualified Pilates instructor. Treatment intervention: a 10-week, 90-minute, 20-session manualised group body psychotherapy group, run by a qualified dance movement psychotherapist. OUTCOMES: The primary outcome was the PANSS negative symptoms subscale score at end of treatment. Secondary outcomes included measures of psychopathology, functional, social, service use and treatment satisfaction outcomes, both at treatment end and at 6-month follow-up. RESULTS: A total of 275 participants were randomised (140 body psychotherapy group, 135 Pilates group). At the end of

  17. Components for digitally controlled aircraft engines

    NASA Technical Reports Server (NTRS)

    Meador, J. D.

    1981-01-01

    Control system components suitable for use in digital electronic control systems are defined. Compressor geometry actuation concepts and fuel handling system concepts suitable for use in large high performance turbofan/turbojet engines are included. Eight conceptual system designs were formulated for the actuation of the compressor geometry. Six conceptual system designs were formulated for the engine fuel handling system. Assessment criteria and weighting factors were established and trade studies performed on their candidate systems to establish the relative merits of the various concepts. Fuel pumping and metering systems for small turboshaft engines were also studied. Seven conceptual designs were formulated, and trade studies performed. A simplified bypassing fuel metering scheme was selected and a preliminary design defined.

  18. Effects of shared medical appointments on quality of life and cost-effectiveness for patients with a chronic neuromuscular disease. Study protocol of a randomized controlled trial

    PubMed Central

    2011-01-01

    Background Shared medical appointments are a series of one-to-one doctor-patient contacts, in presence of a group of 6-10 fellow patients. This group visits substitute the annual control visits of patients with the neurologist. The same items attended to in a one-to- one appointment are addressed. The possible advantages of a shared medical appointment could be an added value to the present management of neuromuscular patients. The currently problem-focused one-to-one out-patient visits often leave little time for the patient's psychosocial needs, patient education, and patient empowerment. Methods/design A randomized, prospective controlled study (RCT) with a follow up of 6 months will be conducted to evaluate the clinical and cost-effectiveness of shared medical appointments compared to usual care for 300 neuromuscular patients and their partners at the Radboud University Nijmegen Medical Center. Every included patient will be randomly allocated to one of the two study arms. This study has been reviewed and approved by the medical ethics committee of the region Arnhem-Nijmegen, the Netherlands. The primary outcome measure is quality of life as measured by the EQ-5D, SF-36 and the Individualized neuromuscular Quality of Life Questionnaire. The primary analysis will be an intention-to-treat analysis on the area under the curve of the quality of life scores. A linear mixed model will be used with random factor group and fixed factors treatment, baseline score and type of neuromuscular disease. For the economic evaluation an incremental cost-effectiveness analysis will be conducted from a societal perspective, relating differences in costs to difference in health outcome. Results are expected in 2012. Discussion This study will be the first randomized controlled trial which evaluates the effect of shared medical appointments versus usual care for neuromuscular patients. This will enable to determine if there is additional value of shared medical appointments to the

  19. Efficacy and cost-effectiveness of a physiotherapy program for chronic rotator cuff pathology: A protocol for a randomised, double-blind, placebo-controlled trial

    PubMed Central

    Bennell, Kim; Coburn, Sally; Wee, Elin; Green, Sally; Harris, Anthony; Forbes, Andrew; Buchbinder, Rachelle

    2007-01-01

    Background Chronic rotator cuff pathology (CRCP) is a common shoulder condition causing pain and disability. Physiotherapy is often the first line of management for CRCP yet there is little conclusive evidence to support or refute its effectiveness and no formal evaluation of its cost-effectiveness. Methods/Design This randomised, double-blind, placebo-controlled trial will involve 200 participants with CRCP recruited from medical practices, outpatient departments and the community via print and radio media. Participants will be randomly allocated to a physiotherapy or placebo group using concealed allocation stratified by treating physiotherapist. Both groups will receive 10 sessions of individual standardised treatment over 10 weeks from one of 10 project physiotherapists. For the following 12 weeks, the physiotherapy group will continue a home exercise program and the placebo group will receive no treatment. The physiotherapy program will comprise shoulder joint and spinal mobilisation, soft tissue massage, postural taping, and home exercises for scapular control, posture and rotator cuff strengthening. The placebo group will receive inactive ultrasound and gentle application of an inert gel over the shoulder region. Blinded assessment will be conducted at baseline and at 10 weeks and 22 weeks after randomisation. The primary outcome measures are self reported questionnaires including the shoulder pain and disability index (SPADI), average pain on an 11-point numeric rating scale and participant perceived global rating of change. Secondary measures include Medical Outcomes Study 36-item short form (SF-36), Assessment of Quality of Life index, numeric rating scales for shoulder pain and stiffness, participant perceived rating of change for pain, strength and stiffness, and manual muscle testing for shoulder strength using a handheld dynamometer. To evaluate cost-effectiveness, participants will record the use of all health-related treatments in a log

  20. Design of a digital controller for spinning flexible spacecraft

    NASA Technical Reports Server (NTRS)

    Kuo, B. C.; Seltzer, S. B.; Singh, G.; Yackel, R. A.

    1974-01-01

    An approach to digital control system design is applied to the analysis and design of a practical onboard digital attitude control system for a class of spinning vehicles characterized by a rigid body and two connected flexible appendages. The approach used is to design a continuous-data control system that will provide a satisfactory system response. Then, using the digital redesign method, a digital controller with onboard digital computer is designed to provide a digital control system whose states are similar to those of the continuous system at sampling instants. The simplicity of application of this approach is indicated by example. The example, using spinning Skylab parameters, is used to substantiate the conclusions.

  1. Digital Camera Control for Faster Inspection

    NASA Technical Reports Server (NTRS)

    Brown, Katharine; Siekierski, James D.; Mangieri, Mark L.; Dekome, Kent; Cobarruvias, John; Piplani, Perry J.; Busa, Joel

    2009-01-01

    Digital Camera Control Software (DCCS) is a computer program for controlling a boom and a boom-mounted camera used to inspect the external surface of a space shuttle in orbit around the Earth. Running in a laptop computer in the space-shuttle crew cabin, DCCS commands integrated displays and controls. By means of a simple one-button command, a crewmember can view low- resolution images to quickly spot problem areas and can then cause a rapid transition to high- resolution images. The crewmember can command that camera settings apply to a specific small area of interest within the field of view of the camera so as to maximize image quality within that area. DCCS also provides critical high-resolution images to a ground screening team, which analyzes the images to assess damage (if any); in so doing, DCCS enables the team to clear initially suspect areas more quickly than would otherwise be possible and further saves time by minimizing the probability of re-imaging of areas already inspected. On the basis of experience with a previous version (2.0) of the software, the present version (3.0) incorporates a number of advanced imaging features that optimize crewmember capability and efficiency.

  2. Cost-Effectiveness of One Year Dementia Follow-Up Care by Memory Clinics or General Practitioners: Economic Evaluation of a Randomised Controlled Trial

    PubMed Central

    Meeuwsen, Els; Melis, René; van der Aa, Geert; Golüke-Willemse, Gertie; de Leest, Benoit; van Raak, Frank; Schölzel-Dorenbos, Carla; Verheijen, Desiree; Verhey, Frans; Visser, Marieke; Wolfs, Claire; Adang, Eddy; Olde Rikkert, Marcel

    2013-01-01

    Objective To evaluate the cost-effectiveness of post-diagnosis dementia treatment and coordination of care by memory clinics compared to general practitioners’ care. Methods A multicentre randomised trial with 175 community dwelling patients newly diagnosed with mild to moderate dementia, and their informal caregivers, with twelve months’ follow-up. Cost-effectiveness was evaluated from a societal point of view and presented as incremental cost per quality adjusted life year. To establish cost-effectiveness, a cost-utility analysis was conducted using utilities based on the EQ-5D. Uncertainty surrounding the incremental cost-effectiveness ratio (difference in costs divided by difference in effects) was calculated by bootstrapping from the original data. Results Compared to general practitioners’ care, treatment by the memory clinics was on average €1024 (95% CI: −€7723 to €5674) cheaper, and showed a non-significant decrease of 0.025 (95% CI: −0.114 to 0.064) quality adjusted life years. The incremental cost-effectiveness point estimate from the bootstrap simulation was € 41 442 per QALY lost if one would use memory clinic care instead of general practitioner care. Conclusion No evidence was found that memory clinics were more cost-effective compared to general practitioners with regard to post-diagnosis treatment and coordination of care of patients with dementia in the first year after diagnosis. Trial Registration ClinicalTrials.gov NCT00554047 PMID:24282511

  3. A real-time digital adaptive tracking controller for a dc motor

    SciTech Connect

    Hwang, S.

    1995-12-31

    The objective of this design is to implement an accurate and cost effective adaptive tracking controller for a DC motor using an 80C196kr microcontroller system. The on-chip embedded functions, optical quadrature encoder and a Pulse Width Modulated (PWM) waveform generator, are used to measure motor positions and generate DC voltages to drive a DC motor respectively. A homing routine that incorporates a photo electric sensor is used to position the motor at a reference point. Users communicate with the system through a 4x4 matrix keypad and 20x2 LCD display or through a PC. The experimental results have shown the validity of this simple microcontroller-based digital control system. This system is performed on a real-time basis, and the control law can be easily replaced by any advanced control laws without changing the hardware setup.

  4. Exploring the comparative cost-effectiveness of economic incentive and command-and-control instruments, and of renewable energy technologies in PM10 emission control: A case study of Lima-Callao, Peru

    NASA Astrophysics Data System (ADS)

    Kroeger, Timm

    Much economic literature expounds the superior cost-effectiveness of economic incentive (EI) policies over command-and-control (CAC) ones, based on appealing theoretical arguments. However, one of the assumptions underlying much of this literature is that monitoring and enforcement (M&E) of policies are not only feasible, but essentially costless. In reality, M&E are never costless and sometimes infeasible, and, crucially, M&E requirements vary across policy types. Furthermore, in technical economic terms, cost-effectiveness is defined with respect to variable costs only; however, in choosing among policies, the objective generally is to identify that with the lowest total (variable plus fixed) cost per unit abatement, which in its own right may be termed cost-effective. The neglect of M&E and of fixed costs throws up the question of the validity of much of the policy advice that draws on the environmental economics literature for developing countries, where the institutional capacity for effective M&E often is strongly limited, and where creating this capacity will require considerable infrastructure investments. The limited institutional capacity also has led to the suggestion that in developing countries, conventional environmental policies, such as input or output taxes, emission charges, or standards, may be less cost-effective than non-conventional environmental policies, such as direct public provision of electricity from renewable sources, because the M&E capacity required for the implementation of non-conventional policies is often less stringent. I test the hypotheses of superior cost-effectiveness of EI over CAC and of non-conventional over conventional environmental policy instruments. The samples of pollution control policies used to test the hypotheses are drawn from a list of frequently recommended urban air pollution abatement measures for developing countries, plus two renewable energy sources. Both sets of environmental policy types are compared

  5. Digital control of magnetic bearings supporting a multimass flexible rotor

    NASA Technical Reports Server (NTRS)

    Keith, F. J.; Williams, R. D.; Allaire, P. E.; Schafer, R. M.

    1993-01-01

    The characteristics of magnetic bearings used to support a three mass flexible rotor operated at speeds up to 14,000 RPM are discussed. The magnetic components of the bearing are of a type reported in the literature previously, but the earlier analog controls were replaced by digital ones. Analog-to-digital and digital-to-analog converters and digital control software were installed in an AT&T PC. This PC-based digital controller was used to operate one of the magnetic bearings on the test rig. Basic proportional-derivative control was applied to the bearings, and the bearing stiffness and damping characteristics were evaluated. Particular attention is paid to the frequency dependent behavior of the stiffness and damping properties, and comparisons are made between the actual controllers and ideal proportional-derivative control.

  6. Cost and cost-effectiveness of nationwide school-based helminth control in Uganda: intra-country variation and effects of scaling-up.

    PubMed

    Brooker, Simon; Kabatereine, Narcis B; Fleming, Fiona; Devlin, Nancy

    2008-01-01

    Estimates of cost and cost-effectiveness are typically based on a limited number of small-scale studies with no investigation of the existence of economies to scale or intra-country variation in cost and cost-effectiveness. This information gap hinders the efficient allocation of health care resources and the ability to generalize estimates to other settings. The current study investigates the intra-country variation in the cost and cost-effectiveness of nationwide school-based treatment of helminth (worm) infection in Uganda. Programme cost data were collected through semi-structured interviews with district officials and from accounting records in six of the 23 intervention districts. Both financial and economic costs were assessed. Costs were estimated on the basis of cost in US$ per schoolchild treated, and an incremental cost-effectiveness ratio (cost in US$ per case of anaemia averted) was used to evaluate programme cost-effectiveness. Sensitivity analysis was performed to assess the effect of discount rate and drug price. The overall economic cost per child treated in the six districts was US$0.54 and the cost-effectiveness was US$3.19 per case of anaemia averted. Analysis indicated that estimates of both cost and cost-effectiveness differ markedly with the total number of children who received treatment, indicating economies of scale. There was also substantial variation between districts in the cost per individual treated (US$0.41-0.91) and cost per anaemia case averted (US$1.70-9.51). Independent variables were shown to be statistically associated with both sets of estimates. This study highlights the potential bias in transferring data across settings without understanding the nature of observed variations. PMID:18024966

  7. COSPAS/SARSAT 406-MHz emergency beacon digital controller

    NASA Astrophysics Data System (ADS)

    Ivancic, William D.

    1988-07-01

    The digital control portion of a low-cost 406-MHz COSPAS/SARSAT emergency beacon has been designed and breadboarded at the NASA Lewis Research Center. This report discusses the requirements and design tradeoffs of the digital controller and describes the hardware and software design, which is available only to United States citizens and companies.

  8. Digital control of wind tunnel magnetic suspension and balance systems

    NASA Technical Reports Server (NTRS)

    Britcher, Colin P.; Goodyer, Michael J.; Eskins, Jonathan; Parker, David; Halford, Robert J.

    1987-01-01

    Digital controllers are being developed for wind tunnel magnetic suspension and balance systems, which in turn permit wind tunnel testing of aircraft models free from support interference. Hardware and software features of two existing digital control systems are reviewed. Some aspects of model position sensing and system calibration are also discussed.

  9. COSPAS/SARSAT 406-MHz emergency beacon digital controller

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.

    1988-01-01

    The digital control portion of a low-cost 406-MHz COSPAS/SARSAT emergency beacon has been designed and breadboarded at the NASA Lewis Research Center. This report discusses the requirements and design tradeoffs of the digital controller and describes the hardware and software design, which is available only to United States citizens and companies.

  10. Cost-effectiveness of controlling emissions for various alternative-fuel vehicle types, with vehicle and fuel price subsidies estimated on the basis of monetary values of emission reductions

    SciTech Connect

    Wang, M.Q.

    1993-12-31

    Emission-control cost-effectiveness is estimated for ten alternative-fuel vehicle (AFV) types (i.e., vehicles fueled with reformulated gasoline, M85 flexible-fuel vehicles [FFVs], M100 FFVs, dedicated M85 vehicles, dedicated M100 vehicles, E85 FFVS, dual-fuel liquefied petroleum gas vehicles, dual-fuel compressed natural gas vehicles [CNGVs], dedicated CNGVs, and electric vehicles [EVs]). Given the assumptions made, CNGVs are found to be most cost-effective in controlling emissions and E85 FFVs to be least cost-effective, with the other vehicle types falling between these two. AFV cost-effectiveness is further calculated for various cases representing changes in costs of vehicles and fuels, AFV emission reductions, and baseline gasoline vehicle emissions, among other factors. Changes in these parameters can change cost-effectiveness dramatically. However, the rank of the ten AFV types according to their cost-effectiveness remains essentially unchanged. Based on assumed dollars-per-ton emission values and estimated AFV emission reductions, the per-vehicle monetary value of emission reductions is calculated for each AFV type. Calculated emission reduction values ranged from as little as $500 to as much as $40,000 per vehicle, depending on AFV type, dollar-per-ton emission values, and baseline gasoline vehicle emissions. Among the ten vehicle types, vehicles fueled with reformulated gasoline have the lowest per-vehicle value, while EVs have the highest per-vehicle value, reflecting the magnitude of emission reductions by these vehicle types. To translate the calculated per-vehicle emission reduction values to individual AFV users, AFV fuel or vehicle price subsidies are designed to be equal to AFV emission reduction values. The subsidies designed in this way are substantial. In fact, providing the subsidies to AFVs would change most AFV types from net cost increases to net cost decreases, relative to conventional gasoline vehicles.

  11. A randomized controlled trial to assess the clinical and cost effectiveness of a nurse-led Antenatal Asthma Management Service in South Australia (AAMS study)

    PubMed Central

    2014-01-01

    Background Pregnancy presents a unique situation for the management of asthma as it can alter the course of asthma severity and its treatment, which in turn can affect pregnancy outcomes. Despite awareness of the substantial adverse effects associated with asthma during pregnancy, little has been done to improve its management and reduce associated perinatal morbidity and mortality. The aim of this randomized controlled trial is to evaluate the clinical and cost effectiveness of an Antenatal Asthma Management Service. Methods/design Design: Multicentre, randomized controlled trial. Inclusion criteria: Women with physician diagnosed asthma, which is not currently in remission, who are less than 20 weeks gestation with a singleton pregnancy and do not have a chronic medical condition. Trial entry and randomization: Eligible women with asthma, stratified by treatment site, disease severity and parity, will be randomized into either the ‘Standard Care Group’ or the ‘Intervention Group’. Study groups: Both groups will be followed prospectively throughout pregnancy. Women in the ‘Standard Care Group’ will receive routine obstetric care reflecting current clinical practice in Australian hospitals. Women in the ‘Intervention Group’ will receive additional care through the nurse-led Antenatal Asthma Management Service, based in the antenatal outpatient clinic. Women will receive asthma education with a full assessment of their asthma at 18, 24, 30 and 36 weeks gestation. Each antenatal visit will include a 60 min session where asthma management skills are assessed including: medication adherence and knowledge, inhaler device technique, recognition of asthma deterioration and possession of a written asthma action plan. Furthermore, subjects will receive education about asthma control and management skills including trigger avoidance and smoking cessation counseling when appropriate. Primary study outcome: Asthma exacerbations during pregnancy. Sample size: A

  12. Clinical effectiveness and cost-effectiveness of physiotherapy and occupational therapy versus no therapy in mild to moderate Parkinson's disease: a large pragmatic randomised controlled trial (PD REHAB).

    PubMed Central

    Clarke, Carl E; Patel, Smitaa; Ives, Natalie; Rick, Caroline E; Woolley, Rebecca; Wheatley, Keith; Walker, Marion F; Zhu, Shihua; Kandiyali, Rebecca; Yao, Guiqing; Sackley, Catherine M

    2016-01-01

    BACKGROUND Cochrane reviews of physiotherapy (PT) and occupational therapy (OT) for Parkinson's disease found insufficient evidence of effectiveness, but previous trials were methodologically flawed with small sample size and short-term follow-up. OBJECTIVES To evaluate the clinical effectiveness and cost-effectiveness of individualised PT and OT in Parkinson's disease. DESIGN Large pragmatic randomised controlled trial. SETTING Thirty-eight neurology and geriatric medicine outpatient clinics in the UK. PARTICIPANTS Seven hundred and sixty-two patients with mild to moderate Parkinson's disease reporting limitations in activities of daily living (ADL). INTERVENTION Patients were randomised online to either both PT and OT NHS services (n = 381) or no therapy (n = 381). Therapy incorporated a patient-centred approach with individual assessment and goal setting. MAIN OUTCOME MEASURES The primary outcome was instrumental ADL measured by the patient-completed Nottingham Extended Activities of Daily Living (NEADL) scale at 3 months after randomisation. Secondary outcomes were health-related quality of life [Parkinson's Disease Questionnaire-39 (PDQ-39); European Quality of Life-5 Dimensions (EQ-5D)], adverse events, resource use and carer quality of life (Short Form questionnaire-12 items). Outcomes were assessed before randomisation and at 3, 9 and 15 months after randomisation. RESULTS Data from 92% of the participants in each group were available at the primary time point of 3 months, but there was no difference in NEADL total score [difference 0.5 points, 95% confidence interval (CI) -0.7 to 1.7; p = 0.4] or PDQ-39 summary index (0.007 points, 95% CI -1.5 to 1.5; p = 1.0) between groups. The EQ-5D quotient was of borderline significance in favour of therapy (-0.03, 95% CI -0.07 to -0.002; p = 0.04). Contact time with therapists was for a median of four visits of 58 minutes each over 8 weeks (mean dose 232 minutes). Repeated measures analysis

  13. REVIEW OF NRC APPROVED DIGITAL CONTROL SYSTEMS ANALYSIS

    SciTech Connect

    D.W. Markman

    1999-09-17

    Preliminary design concepts for the proposed Subsurface Repository at Yucca Mountain indicate extensive reliance on modern, computer-based, digital control technologies. The purpose of this analysis is to investigate the degree to which the U. S. Nuclear Regulatory Commission (NRC) has accepted and approved the use of digital control technology for safety-related applications within the nuclear power industry. This analysis reviews cases of existing digitally-based control systems that have been approved by the NRC. These cases can serve as precedence for using similar types of digitally-based control technologies within the Subsurface Repository. While it is anticipated that the Yucca Mountain Project (YMP) will not contain control systems as complex as those required for a nuclear power plant, the review of these existing NRC approved applications will provide the YMP with valuable insight into the NRCs review process and design expectations for safety-related digital control systems. According to the YMP Compliance Program Guidance, portions of various NUREGS, Regulatory Guidelines, and nuclear IEEE standards the nuclear power plant safety related concept would be applied to some of the designs on a case-by-case basis. This analysis will consider key design methods, capabilities, successes, and important limitations or problems of selected control systems that have been approved for use in the Nuclear Power industry. An additional purpose of this analysis is to provide background information in support of further development of design criteria for the YMP. The scope and primary objectives of this analysis are to: (1) Identify and research the extent and precedence of digital control and remotely operated systems approved by the NRC for the nuclear power industry. Help provide a basis for using and relying on digital technologies for nuclear related safety critical applications. (2) Identify the basic control architecture and methods of key digital control

  14. Novel cost-effective quality control approach for the Cepheid Xpert CT/NG assay for the detection of Chlamydia Trachomatis and Neisseria Gonorrhoeae.

    PubMed

    Chan, Maurice; Jiang, Boran; Ng, Siew Yong Lily; Tan, Thean Yen

    2016-06-01

    The Xpert CT/NG is a rapid assay for detection of Neisseria gonorrhoeae and Chlamydia trachomatis. QC materials must be formulated to emulate human specimens, and are prohibitively expensive. A creative, cost-effective QC approach is proposed. The acceptable sample types for the Xpert CT/NG assay were extended to include eye swabs. PMID:27091503

  15. Cost-effectiveness of intensive multifactorial treatment compared with routine care for individuals with screen-detected Type 2 diabetes: analysis of the ADDITION-UK cluster-randomized controlled trial

    PubMed Central

    Tao, L; Wilson, E C F; Wareham, N J; Sandbæk, A; Rutten, G E H M; Lauritzen, T; Khunti, K; Davies, M J; Borch-Johnsen, K; Griffin, S J; Simmons, R K

    2015-01-01

    Aims To examine the short- and long-term cost-effectiveness of intensive multifactorial treatment compared with routine care among people with screen-detected Type 2 diabetes. Methods Cost–utility analysis in ADDITION-UK, a cluster-randomized controlled trial of early intensive treatment in people with screen-detected diabetes in 69 UK general practices. Unit treatment costs and utility decrement data were taken from published literature. Accumulated costs and quality-adjusted life years (QALYs) were calculated using ADDITION-UK data from 1 to 5 years (short-term analysis, n = 1024); trial data were extrapolated to 30 years using the UKPDS outcomes model (version 1.3) (long-term analysis; n = 999). All costs were transformed to the UK 2009/10 price level. Results Adjusted incremental costs to the NHS were £285, £935, £1190 and £1745 over a 1-, 5-, 10- and 30-year time horizon, respectively (discounted at 3.5%). Adjusted incremental QALYs were 0.0000, – 0.0040, 0.0140 and 0.0465 over the same time horizons. Point estimate incremental cost-effectiveness ratios (ICERs) suggested that the intervention was not cost-effective although the ratio improved over time: the ICER over 10 years was £82 250, falling to £37 500 over 30 years. The ICER fell below £30 000 only when the intervention cost was below £631 per patient: we estimated the cost at £981. Conclusion Given conventional thresholds of cost-effectiveness, the intensive treatment delivered in ADDITION was not cost-effective compared with routine care for individuals with screen-detected diabetes in the UK. The intervention may be cost-effective if it can be delivered at reduced cost. PMID:25661661

  16. Digital Control System For Wind-Tunnel Model

    NASA Technical Reports Server (NTRS)

    Hoadley, Sherwood T.; Mcgraw, Sandra

    1995-01-01

    Multiple functions performed by multiple coordinated processors for real-time control. Multiple input, multiple-output, multiple-function digital control system developed for wind-tunnel model of advanced fighter airplane with actively controlled flexible wings. Digital control system provides flexibility in selection of control laws, sensors, and actuators, plus some redundancy to accommodate failures in some of its subsystems. Implements feedback control scheme providing simultaneously for suppression of flutter, control of roll angle, roll-rate tracking during maximized roll maneuvers, and alleviation of loads during roll maneuvers.

  17. Digital Controller For Laser-Beam-Steering Subsystem

    NASA Technical Reports Server (NTRS)

    Ansari, Homayoon

    1995-01-01

    Report presents additional information about proposed apparatus described in "Beam-Steering Subsystem for Laser Communication" (NPO-19069). Discusses design of digital beam-steering control subsystem and, in particular, that part of design pertaining to digital compensation for frequency response of steering mirror.

  18. Implementation of Adaptive Digital Controllers on Programmable Logic Devices

    NASA Technical Reports Server (NTRS)

    Gwaltney, David A.; King, Kenneth D.; Smith, Keary J.; Monenegro, Justino (Technical Monitor)

    2002-01-01

    Much has been made of the capabilities of FPGA's (Field Programmable Gate Arrays) in the hardware implementation of fast digital signal processing. Such capability also makes an FPGA a suitable platform for the digital implementation of closed loop controllers. Other researchers have implemented a variety of closed-loop digital controllers on FPGA's. Some of these controllers include the widely used proportional-integral-derivative (PID) controller, state space controllers, neural network and fuzzy logic based controllers. There are myriad advantages to utilizing an FPGA for discrete-time control functions which include the capability for reconfiguration when SRAM-based FPGA's are employed, fast parallel implementation of multiple control loops and implementations that can meet space level radiation tolerance requirements in a compact form-factor. Generally, a software implementation on a DSP (Digital Signal Processor) or microcontroller is used to implement digital controllers. At Marshall Space Flight Center, the Control Electronics Group has been studying adaptive discrete-time control of motor driven actuator systems using digital signal processor (DSP) devices. While small form factor, commercial DSP devices are now available with event capture, data conversion, pulse width modulated (PWM) outputs and communication peripherals, these devices are not currently available in designs and packages which meet space level radiation requirements. In general, very few DSP devices are produced that are designed to meet any level of radiation tolerance or hardness. The goal of this effort is to create a fully digital, flight ready controller design that utilizes an FPGA for implementation of signal conditioning for control feedback signals, generation of commands to the controlled system, and hardware insertion of adaptive control algorithm approaches. An alternative is required for compact implementation of such functionality to withstand the harsh environment

  19. The "Cost-Effectiveness" of Sim One

    ERIC Educational Resources Information Center

    Hoffman, Kaaren I.; Abrahamson, Stephen

    1975-01-01

    Sim One is a computer-controlled patient, a sophisticated simulator developed by the University of Southern California School of Medicine. This article summarizes fifteen cost-effectiveness studies conducted over a 2-year period. Savings with the use of Sim One were found to justify the cost within a short period. (JT)

  20. COST EFFECTIVE VOC EMISSION CONTROL STARTEGIES FOR MILITARY, AEROSPACE,AND INDUSTRIAL PAINT SPRAY BOOTH OPERATIONS: COMBINING IMPROVED VENTILATION SYSTEMS WITH INNOVATIVE, LOW COST EMISSION CONTROL TECHNOLOGIES

    EPA Science Inventory

    The paper describes a full-scale demonstration program in which several paint booths were modified for recirculation ventilation; the booth exhaust streams are vented to an innovative volatile organic compound (VOC) emission control system having extremely low operating costs. ...

  1. F-15 digital electronic engine control system description

    NASA Technical Reports Server (NTRS)

    Myers, L. P.

    1984-01-01

    A digital electronic engine control (DEEC) was developed for use on the F100-PW-100 turbofan engine. This control system has full authority control, capable of moving all the controlled variables over their full ranges. The digital computational electronics and fault detection and accomodation logic maintains safe engine operation. A hydromechanical backup control (BUC) is an integral part of the fuel metering unit and provides gas generator control at a reduced performance level in the event of an electronics failure. The DEEC's features, hardware, and major logic diagrams are described.

  2. Implementation of DSP Based Cost Effective Inverter Fed Induction Motor Drive with VisSim

    NASA Astrophysics Data System (ADS)

    Mohanty, Nalin K.; Muthu, Ranganath

    2012-03-01

    The implementation of a Digital Signal Processor (DSP) based high-performance cost effective fed Induction Motor drive with VisSim/Embedded Controls Developer (ECD) is presented in this paper. In the experimental work VisSim/ECD software automatically converts the in built block diagram to C code and compiles, links, and downloads the code to DSP processor TMS320F2812. The DSP processor generates the required PWM to a cost effective ie four switch 3-phase (FSTPI) inverter. The power circuit of FSTPI fed drive system consists of an IGBT based FSTPI bridge inverter module feeding to a 5 hp three-phase squirrel cage induction motor. In this work the speed of induction motor output is shown by the GUI of VisSim/ECD and SPWM pulses, line voltages and line current output curves are shown using digital storage oscilloscope to demonstrate the feasibility of the system.

  3. Trends in software reliability for digital flight control

    NASA Technical Reports Server (NTRS)

    Hecht, H.; Hecht, M.

    1983-01-01

    Software error data of major recent Digital Flight Control Systems Development Programs. The report summarizes the data, compare these data with similar data from previous surveys and identifies trends and disciplines to improve software reliability.

  4. A method for reducing sampling jitter in digital control systems

    NASA Technical Reports Server (NTRS)

    Anderson, T. O.; HURBD W. J.; Hurd, W. J.

    1969-01-01

    Digital phase lock loop system is designed by smoothing the proportional control with a low pass filter. This method does not significantly affect the loop dynamics when the smoothing filter bandwidth is wide compared to loop bandwidth.

  5. Implementation of Adaptive Digital Controllers on Programmable Logic Devices

    NASA Technical Reports Server (NTRS)

    Gwaltney, David A.; King, Kenneth D.; Smith, Keary J.; Ormsby, John (Technical Monitor)

    2002-01-01

    Much has been made of the capabilities of FPGA's (Field Programmable Gate Arrays) in the hardware implementation of fast digital signal processing (DSP) functions. Such capability also makes and FPGA a suitable platform for the digital implementation of closed loop controllers. There are myriad advantages to utilizing an FPGA for discrete-time control functions which include the capability for reconfiguration when SRAM- based FPGA's are employed, fast parallel implementation of multiple control loops and implementations that can meet space level radiation tolerance in a compact form-factor. Other researchers have presented the notion that a second order digital filter with proportional-integral-derivative (PID) control functionality can be implemented in an FPGA. At Marshall Space Flight Center, the Control Electronics Group has been studying adaptive discrete-time control of motor driven actuator systems using digital signal processor (DSF) devices. Our goal is to create a fully digital, flight ready controller design that utilizes an FPGA for implementation of signal conditioning for control feedback signals, generation of commands to the controlled system, and hardware insertion of adaptive control algorithm approaches. While small form factor, commercial DSP devices are now available with event capture, data conversion, pulse width modulated outputs and communication peripherals, these devices are not currently available in designs and packages which meet space level radiation requirements. Meeting our goals requires alternative compact implementation of such functionality to withstand the harsh environment encountered on spacecraft. Radiation tolerant FPGA's are a feasible option for reaching these goals.

  6. Implementation of Adaptive Digital Controllers on Programmable Logic Devices

    NASA Technical Reports Server (NTRS)

    Gwaltney, David A.; King, Kenneth D.; Smith, Keary J.; Montenegro, Justino (Technical Monitor)

    2002-01-01

    Much has been made of the capabilities of Field Programmable Gate Arrays (FPGA's) in the hardware implementation of fast digital signal processing functions. Such capability also makes an FPGA a suitable platform for the digital implementation of closed loop controllers. Other researchers have implemented a variety of closed-loop digital controllers on FPGA's. Some of these controllers include the widely used Proportional-Integral-Derivative (PID) controller, state space controllers, neural network and fuzzy logic based controllers. There are myriad advantages to utilizing an FPGA for discrete-time control functions which include the capability for reconfiguration when SRAM- based FPGA's are employed, fast parallel implementation of multiple control loops and implementations that can meet space level radiation tolerance requirements in a compact form-factor. Generally, a software implementation on a Digital Signal Processor (DSP) device or microcontroller is used to implement digital controllers. At Marshall Space Flight Center, the Control Electronics Group has been studying adaptive discrete-time control of motor driven actuator systems using DSP devices. While small form factor, commercial DSP devices are now available with event capture, data conversion, Pulse Width Modulated (PWM) outputs and communication peripherals, these devices are not currently available in designs and packages which meet space level radiation requirements. In general, very few DSP devices are produced that are designed to meet any level of radiation tolerance or hardness. An alternative is required for compact implementation of such functionality to withstand the harsh environment encountered on spacemap. The goal of this effort is to create a fully digital, flight ready controller design that utilizes an FPGA for implementation of signal conditioning for control feedback signals, generation of commands to the controlled system, and hardware insertion of adaptive-control algorithm

  7. The design of digital-adaptive controllers for VTOL aircraft

    NASA Technical Reports Server (NTRS)

    Stengel, R. F.; Broussard, J. R.; Berry, P. W.

    1976-01-01

    Design procedures for VTOL automatic control systems have been developed and are presented. Using linear-optimal estimation and control techniques as a starting point, digital-adaptive control laws have been designed for the VALT Research Aircraft, a tandem-rotor helicopter which is equipped for fully automatic flight in terminal area operations. These control laws are designed to interface with velocity-command and attitude-command guidance logic, which could be used in short-haul VTOL operations. Developments reported here include new algorithms for designing non-zero-set-point digital regulators, design procedures for rate-limited systems, and algorithms for dynamic control trim setting.

  8. Digitally controlling the 'twist' of light

    NASA Astrophysics Data System (ADS)

    Dudley, A.; Forbes, A.

    2014-08-01

    An overview of the work done within the Mathematical Optics group at the CSIR's National Laser Centre will be presented. We will focus on our work done in laser beam shaping with the use of digital holograms for the generation of superimposed optical fields which carry orbital angular momentum (OAM) and the development of OAM measurement techniques. Since OAM offers a potentially infinite-dimensional state space, much interest has been generated in its measurement for higher-dimensional quantum information processing to be realised. We generate superpositions of higher-order Bessel beams and show that even though we can create a field which carries no overall OAM, we can still witness an angular rotation in the intensity profile of the beam. We also develop a new OAM measurement technique by means of digital holograms.

  9. Digital adaptive control laws for the F-8

    NASA Technical Reports Server (NTRS)

    Hartmann, G. L.; Harvey, C. A.

    1976-01-01

    NASA is conducting a flight control research program in digital fly-by-wire technology using a modified F-8C aircraft. The first phase of this program used Apollo hardware to demonstrate the practicality of digital fly-by-wire in an actual test vehicle. For the second phase, conventional aircraft sensors and a large floating point digital computer are being utilized to test advanced control laws and redundancy concepts. As part of NASA's research in digital fly-by-wire technology, Honeywell developed digital adaptive flight control laws for flight test in the F-8C. Adaptation of the control laws was to be based on information sensed from conventional aircraft sensors excluding air data. The control laws were constrained to use only existing elevator, rudder, and ailerons as control effectors, each powered by existing actuators. Three adaptive control laws were successfully designed using maximum likelihood estimation, a Liapunov stable model tracker and a self-excited limit cycle concept. The maximum likelihood estimation design was selected as the most promising because of its capability to identify more than surface effectiveness parameters. The adaptive concepts, the control laws and comparisons of predicted performance are described.

  10. A within-trial cost-effectiveness analysis of primary care referral to a commercial provider for weight loss treatment, relative to standard care—an international randomised controlled trial

    PubMed Central

    Fuller, N R; Colagiuri, S; Schofield, D; Olson, A D; Shrestha, R; Holzapfel, C; Wolfenstetter, S B; Holle, R; Ahern, A L; Hauner, H; Jebb, S A; Caterson, I D

    2013-01-01

    Background: Due to the high prevalence of overweight and obesity there is a need to identify cost-effective approaches for weight loss in primary care and community settings. Objective: We evaluated the cost effectiveness of two weight loss programmes of 1-year duration, either standard care (SC) as defined by national guidelines, or a commercial provider (Weight Watchers) (CP). Design: This analysis was based on a randomised controlled trial of 772 adults (87% female; age 47.4±12.9 years; body mass index 31.4±2.6 kg m−2) recruited by health professionals in primary care in Australia, United Kingdom and Germany. Both a health sector and societal perspective were adopted to calculate the cost per kilogram of weight loss and the ICER, expressed as the cost per quality adjusted life year (QALY). Results: The cost per kilogram of weight loss was USD122, 90 and 180 for the CP in Australia, the United Kingdom and Germany, respectively. For SC the cost was USD138, 151 and 133, respectively. From a health-sector perspective, the ICER for the CP relative to SC was USD18 266, 12 100 and 40 933 for Australia, the United Kingdom and Germany, respectively. Corresponding societal ICER figures were USD31 663, 24 996 and 51 571. Conclusion: The CP was a cost-effective approach from a health funder and societal perspective. Despite participants in the CP group attending two to three times more meetings than the SC group, the CP was still cost effective even including these added patient travel costs. This study indicates that it is cost effective for general practitioners (GPs) to refer overweight and obese patients to a CP, which may be better value than expending public funds on GP visits to manage this problem. PMID:22929209

  11. Cost-effectiveness of a tailored intervention designed to increase breast cancer screening among a non-adherent population: a randomized controlled trial

    PubMed Central

    2012-01-01

    Background Although the percentage of women who initiate breast cancer screening is rising, the rate of continued adherence is poor. The purpose of this study was to examine the effectiveness and cost-effectiveness of a tailored print intervention compared with a non-tailored print intervention for increasing the breast cancer screening rate among a non-adherent population. Methods In total, 1859 participants aged 51–59 years (except those aged 55 years) were recruited from a Japanese urban community setting. Participants were randomly assigned to receive either a tailored print reminder (tailored intervention group) or non-tailored print reminder (non-tailored intervention group). The primary outcome was improvement in the breast cancer screening rate. The screening rates and cost-effectiveness were examined for each treatment group (tailored vs. non-tailored) and each intervention subgroup during a follow-up period of five months. All analyses followed the intention-to-treat principle. Results The number of women who underwent a screening mammogram following the reminder was 277 (19.9%) in the tailored reminder group and 27 (5.8%) in the non-tailored reminder group. A logistic regression model revealed that the odds of a woman who received a tailored print reminder undergoing mammography was 4.02 times those of a women who had received a non-tailored print reminder (95% confidence interval, 2.67–6.06). The cost of one mammography screening increase was 2,544 JPY or 30 USD in the tailored intervention group and 4,366 JPY or 52 USD in the non-tailored intervention group. Conclusions Providing a tailored print reminder was an effective and cost-effective strategy for improving breast cancer screening rates among non-adherent women. PMID:22962858

  12. A cost-effectiveness analysis of provider and community interventions to improve the treatment of uncomplicated malaria in Nigeria: study protocol for a randomized controlled trial

    PubMed Central

    2012-01-01

    Background There is mounting evidence of poor adherence by health service personnel to clinical guidelines for malaria following a symptomatic diagnosis. In response to this, the World Health Organization (WHO) recommends that in all settings clinical suspicion of malaria should be confirmed by parasitological diagnosis using microscopy or Rapid Diagnostic Test (RDT). The Government of Nigeria plans to introduce RDTs in public health facilities over the coming year. In this context, we will evaluate the effectiveness and cost-effectiveness of two interventions designed to support the roll-out of RDTs and improve the rational use of ACTs. It is feared that without supporting interventions, non-adherence will remain a serious impediment to implementing malaria treatment guidelines. Methods/design A three-arm stratified cluster randomized trial is used to compare the effectiveness and cost-effectiveness of: (1) provider malaria training intervention versus expected standard practice in malaria diagnosis and treatment; (2) provider malaria training intervention plus school-based intervention versus expected standard practice; and (3) the combined provider plus school-based intervention versus provider intervention alone. RDTs will be introduced in all arms of the trial. The primary outcome is the proportion of patients attending facilities that report a fever or suspected malaria and receive treatment according to malaria guidelines. This will be measured by surveying patients (or caregivers) as they exit primary health centers, pharmacies, and patent medicine dealers. Cost-effectiveness will be presented in terms of the primary outcome and a range of secondary outcomes, including changes in provider and community knowledge. Costs will be estimated from both a societal and provider perspective using standard economic evaluation methodologies. Trial registration Clinicaltrials.gov NCT01350752 PMID:22682276

  13. AFTI/F-16 digital flight control system experience

    NASA Technical Reports Server (NTRS)

    Mackall, D. A.

    1984-01-01

    The Advanced Flighter Technology Integration (AFTI) F-16 program is investigating the integration of emerging technologies into an advanced fighter aircraft. The three major technologies involved are the triplex digital flight control system; decoupled aircraft flight control; and integration of avionics, pilot displays, and flight control. In addition to investigating improvements in fighter performance, the AFTI/F-16 program provides a look at generic problems facing highly integrated, flight-crucial digital controls. An overview of the AFTI/F-16 systems is followed by a summary of flight test experience and recommendations.

  14. Integrated low power digital gyro control electronics

    NASA Technical Reports Server (NTRS)

    M'Closkey, Robert (Inventor); Challoner, A. Dorian (Inventor); Grayver, Eugene (Inventor); Hayworth, Ken J. (Inventor)

    2005-01-01

    Embodiments of the invention generally encompass a digital, application specific integrated circuit (ASIC) has been designed to perform excitation of a selected mode within a vibratory rate gyroscope, damping, or force-rebalance, of other modes within the sensor, and signal demodulation of the in-phase and quadrature components of the signal containing the angular rate information. The ASIC filters dedicated to each channel may be individually programmed to accommodate different rate sensor designs/technology or variations within the same class of sensors. The ASIC architecture employs a low-power design, making the ASIC, particularly suitable for use in power-sensitive applications.

  15. Fault tolerant programmable digital attitude control electronics study

    NASA Technical Reports Server (NTRS)

    Sorensen, A. A.

    1974-01-01

    The attitude control electronics mechanization study to develop a fault tolerant autonomous concept for a three axis system is reported. Programmable digital electronics are compared to general purpose digital computers. The requirements, constraints, and tradeoffs are discussed. It is concluded that: (1) general fault tolerance can be achieved relatively economically, (2) recovery times of less than one second can be obtained, (3) the number of faulty behavior patterns must be limited, and (4) adjoined processes are the best indicators of faulty operation.

  16. MAS2-8 radar and digital control unit

    NASA Technical Reports Server (NTRS)

    Oberg, J. M.; Ulaby, F. T.

    1974-01-01

    The design of the MAS 2-8 (2 to 8 GHz microwave-active spectrometer), a ground-based sensor system, is presented. A major modification in 1974 to the MAS 2-8, that of a control subsystem to automate the data-taking operation, is the prime focus. The digital control unit automatically changes all system parameters except FM rate and records the return signal on paper tape. The overall system operation and a detailed discussion of the design and operation of the digital control unit are presented.

  17. Using a digital signal processor as a data stream controller for digital subtraction angiography

    SciTech Connect

    Meng, J.D.; Katz, J.E.

    1991-10-01

    High speed, flexibility, and good arithmetic abilities make digital signal processors (DSP) a good choice as input/output controllers for real time applications. The DSP can be made to pre-process data in real time to reduce data volume, to open early windows on what is being acquired and to implement local servo loops. We present an example of a DSP as an input/output controller for a digital subtraction angiographic imaging system. The DSP pre-processes the raw data, reducing data volume by a factor of two, and is potentially capable of producing real-time subtracted images for immediate display.

  18. Using a digital signal processor as a data stream controller in digital subtraction angiography

    SciTech Connect

    Meng, J.D.; Katz, J.E. )

    1993-04-01

    High speed, flexibility, and good arithmetic abilities make digital signal processors (DSP) a good choice as input/output controllers for real time applications. The DSP can be made to pre-process data in real time to reduce data volume, to open early windows on what is being acquired and to implement input/output controller for a digital subtraction angiographic imaging system. The DSP pre-processes the raw data, reducing data volume by a factor of two, and is potentially capable of producing real-time subtracted images for immediate display.

  19. Digital control in LLRF system for CYCIAE-100 cyclotron

    NASA Astrophysics Data System (ADS)

    Yin, Zhiguo; Fu, Xiaoliang; Ji, Bin; Zhang, Tianjue; Wang, Chuan

    2016-05-01

    As a driven accelerator, the CYCIAE-100 cyclotron is designed by China Institute of Atomic Energy for the Beijing Radio Ion-beam Facility project. The cyclotron RF system is designed to use two RF power sources of 100 kW to drive two half-wavelength cavities respectively. Two Dee accelerating electrodes are kept separately from each other inside the cyclotron, while their accelerating voltages are maintained in phase by the efforts of LLRF control. An analog-digital hybrid LLRF system has been developed to achieve cavity tuning control, dee voltage amplitude and phase stabilization etc. The analog subsystems designs are focused on RF signal up/down conversion, tuning control, and dee voltage regulation. The digital system provides an RF signal source, aligns the cavity phases and maintains a Finite State Machine. The digital parts combine with the analog functions to provide the LLRF control. A brief system hardware introduction will be given in this paper, followed by the review of several major characteristics of the digital control in the 100 MeV cyclotron LLRF system. The commissioning is also introduced, and most of the optimization during the process was done by changing the digital parts.

  20. Relationships between digital signal processing and control and estimation theory

    NASA Technical Reports Server (NTRS)

    Willsky, A. S.

    1978-01-01

    Research directions in the fields of digital signal processing and modern control and estimation theory are discussed. Stability theory, linear prediction and parameter identification, system synthesis and implementation, two-dimensional filtering, decentralized control and estimation, and image processing are considered in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the disciplines.

  1. Cost effective management of space venture risks

    NASA Technical Reports Server (NTRS)

    Giuntini, Ronald E.; Storm, Richard E.

    1986-01-01

    The development of a model for the cost-effective management of space venture risks is discussed. The risk assessment and control program of insurance companies is examined. A simplified system development cycle which consists of a conceptual design phase, a preliminary design phase, a final design phase, a construction phase, and a system operations and maintenance phase is described. The model incorporates insurance safety risk methods and reliability engineering, and testing practices used in the development of large aerospace and defense systems.

  2. Progress in multirate digital control system design

    NASA Technical Reports Server (NTRS)

    Berg, Martin C.; Mason, Gregory S.

    1991-01-01

    A new methodology for multirate sampled-data control design based on a new generalized control law structure, two new parameter-optimization-based control law synthesis methods, and a new singular-value-based robustness analysis method are described. The control law structure can represent multirate sampled-data control laws of arbitrary structure and dynamic order, with arbitrarily prescribed sampling rates for all sensors and update rates for all processor states and actuators. The two control law synthesis methods employ numerical optimization to determine values for the control law parameters. The robustness analysis method is based on the multivariable Nyquist criterion applied to the loop transfer function for the sampling period equal to the period of repetition of the system's complete sampling/update schedule. The complete methodology is demonstrated by application to the design of a combination yaw damper and modal suppression system for a commercial aircraft.

  3. A Digital Self Excited Loop for Accelerating Cavity Field Control

    SciTech Connect

    Curt Hovater; Trent Allison; Jean Delayen; John Musson; Tomasz Plawski

    2007-06-22

    We have developed a digital process that emulates an analog oscillator and ultimately a self excited loop (SEL) for field control. The SEL, in its analog form, has been used for many years for accelerating cavity field control. In essence the SEL uses the cavity as a resonant circuit -- much like a resonant (tank) circuit is used to build an oscillator. An oscillating resonant circuit can be forced to oscillate at different, but close, frequencies to resonance by applying a phase shift in the feedback path. This allows the circuit to be phased-locked to a master reference, which is crucial for multiple cavity accelerators. For phase and amplitude control the SEL must be forced to the master reference frequency, and feedback provided for in both dimensions. The novelty of this design is in the way digital signal processing (DSP) is structured to emulate an analog system. While the digital signal processing elements are not new, to our knowledge this is the first time that the digital SEL concept has been designed and demonstrated. This paper reports on the progress of the design and implementation of the digital SEL for field control of superconducting accelerating cavities.

  4. User`s manual for the CDC-1 digitizer controller

    SciTech Connect

    Ferron, J.R.

    1994-09-01

    A detailed description of how to use the CDC-1 digitizer controller is given. The CDC-1 is used with the CAMAC format digitizer models in the TRAQ series (manufactured by DSP Technology Inc.), the DAD-1 data acquisition daughter board, and the Intel i860-based SuperCard-2 (manufactured, by CSP Inc.) to form a high speed data acquisition and real time analysis system. Data can be transferred to the memory on the SuperCard-2 at a rate as high as 40 million 14-bit samples per second. Depending on the model of TRAQ digitizer in use, digitizing rates up to 3.33 MHz are supported (with eight data channels), or, for instance, at a sample rate of 100 kHz, 384 data channels can be acquired.

  5. An Inexpensive Digital Gradient Controller for HPLC.

    ERIC Educational Resources Information Center

    Brady, James E.; Carr, Peter W.

    1983-01-01

    Use of gradient elution techniques in high performance liquid chromatography (HPLC) is often essential for direct separation of complex mixtures. Since most commercial controllers have features that are of marginal value for instructional purposes, a low-cost controller capable of illustrating essential features of gradient elution was developed.…

  6. Stress testing of digital flight-control system software

    NASA Technical Reports Server (NTRS)

    Rajan, N.; Defeo, P. V.; Saito, J.

    1983-01-01

    A technique for dynamically testing digital flight-control system software on a module-by-module basis is described. Each test module is repetitively executed faster than real-time with an exhaustive input sequence. Outputs of the test module are compared with outputs generated by an alternate, simpler implementation for the same input data. Discrepancies between the two sets of output indicate the possible presence of a software error. The results of an implementation of this technique in the Digital Flight-Control System Software Verification Laboratory are discussed.

  7. Digital control of diode laser for atmospheric spectroscopy

    NASA Technical Reports Server (NTRS)

    Menzies, R. T.; Rutledge, C. W. (Inventor)

    1985-01-01

    A system is described for remote absorption spectroscopy of trace species using a diode laser tunable over a useful spectral region of 50 to 200 cm(-1) by control of diode laser temperature over range from 15 K to 100 K, and tunable over a smaller region of typically 0.1 to 10 cm(-1) by control of the diode laser current over a range from 0 to 2 amps. Diode laser temperature and current set points are transmitted to the instrument in digital form and stored in memory for retrieval under control of a microprocessor during measurements. The laser diode current is determined by a digital to analog converter through a field effect transistor for a high degree of ambient temperature stability, while the laser diode temperature is determined by set points entered into a digital to analog converter under control of the microprocessor. Temperature of the laser diode is sensed by a sensor diode to provide negative feedback to the temperature control circuit that responds to the temperature control digital to analog converter.

  8. Digital regulation of a phase controlled power converter

    SciTech Connect

    Schultheiss, C.; Haque, T.

    1995-12-01

    The Relativistic Heavy Ion Collider, now in construction at Brookhaven National Laboratory, will use phase controlled power converters for the main dipole and quadrupole magnet strings. The rectifiers in these power supplies will be controlled by a digital regulator based on the TI 320C30 Digital Signal Processor (DSP). The DSP implements the current loop, the voltage loop, and a system to actively reduce the sub-harmonic ripple components. Digital firing circuits consisting of a phase locked lop and counters are used to fire the SCRs. Corrections for the sub-harmonic reduction are calculated by the DSP and stored in registers in the firing circuit. These corrections are added in hardware, to the over-all firing count provided by the DSP. the resultant count is compared to a reference counter to fire the SCRs. This combination of a digital control system and the digital firing circuits allows the correction of the sub-harmonics in a real-time sense. A prototype of the regulator has been constructed, and the preliminary testing indicates a sub-harmonic reduction of 60 dB.

  9. Digital computer control of a 30-cm mercury ion thruster

    NASA Technical Reports Server (NTRS)

    Low, C. A., Jr.

    1975-01-01

    The major objective was to define the exact role of an onboard spacecraft computer in the control of ion thrusters. An initial computer control system with accurate high speed capability was designed, programmed, and tested with the computer as the sole control element for an operating ion thruster. The command functions and a code format for a spacecraft digital control system were established. A second computer control system was constructed to operate with these functions and format. A throttle program sequence was established and tested. A two thruster array was tested with these computer control systems and the results reported.

  10. Digital computer control of a 30 cm mercury ion thruster

    NASA Technical Reports Server (NTRS)

    Low, C. A., Jr.

    1975-01-01

    The major objective of this program was to define the exact role of an on-board spacecraft computer in the control of ion thrusters. An initial computer control system with accurate high speed capability was designed, programmed, and tested with the computer as the sole control element for an operating ion thruster. The command functions and a code format for a spacecraft digital control system were established. A second computer control system was constructed to operate with these functions and format. A throttle program sequence was established and tested. A two thruster array was tested with these computer control systems and the results reported.