Drug error in paediatric anaesthesia: current status and where to go now.

PubMed

Anderson, Brian J

2018-06-01

Medication errors in paediatric anaesthesia and the perioperative setting continue to occur despite widespread recognition of the problem and published advice for reduction of this predicament at international, national, local and individual levels. Current literature was reviewed to ascertain drug error rates and to appraise causes and proposed solutions to reduce these errors. The medication error incidence remains high. There is documentation of reduction through identification of causes with consequent education and application of safety analytics and quality improvement programs in anaesthesia departments. Children remain at higher risk than adults because of additional complexities such as drug dose calculations, increased susceptibility to some adverse effects and changes associated with growth and maturation. Major improvements are best made through institutional system changes rather than a commitment to do better on the part of each practitioner. Medication errors in paediatric anaesthesia represent an important risk to children and most are avoidable. There is now an understanding of the genesis of adverse drug events and this understanding should facilitate the implementation of known effective countermeasures. An institution-wide commitment and strategy are the basis for a worthwhile and sustained improvement in medication safety.

Addition to the Lewis Chemical Equilibrium Program to allow computation from coal composition data

NASA Technical Reports Server (NTRS)

Sevigny, R.

1980-01-01

Changes made to the Coal Gasification Project are reported. The program was developed by equilibrium combustion in rocket engines. It can be applied directly to the entrained flow coal gasification process. The particular problem addressed is the reduction of the coal data into a form suitable to the program, since the manual process is involved and error prone. A similar problem in relating the normal output of the program to parameters meaningful to the coal gasification process is also addressed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Z.; Pike, R.W.; Hertwig, T.A.

An effective approach for source reduction in chemical plants has been demonstrated using on-line optimization with flowsheeting (ASPEN PLUS) for process optimization and parameter estimation and the Tjao-Biegler algorithm implemented in a mathematical programming language (GAMS/MINOS) for data reconciliation and gross error detection. Results for a Monsanto sulfuric acid plant with a Bailey distributed control system showed a 25% reduction in the sulfur dioxide emissions and a 17% improvement in the profit over the current operating conditions. Details of the methods used are described.

42 CFR 482.21 - Condition of participation: Quality assessment and performance improvement program.

Code of Federal Regulations, 2013 CFR

2013-10-01

... quality improvement and patient safety, including the reduction of medical errors, is defined, implemented... address priorities for improved quality of care and patient safety; and that all improvement actions are... incorporate quality indicator data including patient care data, and other relevant data, for example...

42 CFR 482.21 - Condition of participation: Quality assessment and performance improvement program.

Code of Federal Regulations, 2014 CFR

2014-10-01

... quality improvement and patient safety, including the reduction of medical errors, is defined, implemented... address priorities for improved quality of care and patient safety; and that all improvement actions are... incorporate quality indicator data including patient care data, and other relevant data, for example...

42 CFR 482.21 - Condition of participation: Quality assessment and performance improvement program.

Code of Federal Regulations, 2012 CFR

2012-10-01

... quality improvement and patient safety, including the reduction of medical errors, is defined, implemented... address priorities for improved quality of care and patient safety; and that all improvement actions are... incorporate quality indicator data including patient care data, and other relevant data, for example...

Final report on the development of the geographic position locator (GPL). Volume 12. Data reduction A3FIX: subroutine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niven, W.A.

The long-term position accuracy of an inertial navigation system depends primarily on the ability of the gyroscopes to maintain a near-perfect reference orientation. Small imperfections in the gyroscopes cause them to drift slowly away from their initial orientation, thereby producing errors in the system's calculations of position. The A3FIX is a computer program subroutine developed to estimate inertial navigation system gyro drift rates with the navigator stopped or moving slowly. It processes data of the navigation system's position error to arrive at estimates of the north- south and vertical gyro drift rates. It also computes changes in the east--west gyromore » drift rate if the navigator is stopped and if data on the system's azimuth error changes are also available. The report describes the subroutine, its capabilities, and gives examples of gyro drift rate estimates that were computed during the testing of a high quality inertial system under the PASSPORT program at the Lawrence Livermore Laboratory. The appendices provide mathematical derivations of the estimation equations that are used in the subroutine, a discussion of the estimation errors, and a program listing and flow diagram. The appendices also contain a derivation of closed form solutions to the navigation equations to clarify the effects that motion and time-varying drift rates induce in the phase-plane relationships between the Schulerfiltered errors in latitude and azimuth snd between the Schulerfiltered errors in latitude and longitude. (auth)« less

Cost-effectiveness of the stream-gaging program in Nebraska

USGS Publications Warehouse

Engel, G.B.; Wahl, K.L.; Boohar, J.A.

1984-01-01

This report documents the results of a study of the cost-effectiveness of the streamflow information program in Nebraska. Presently, 145 continuous surface-water stations are operated in Nebraska on a budget of $908,500. Data uses and funding sources are identified for each of the 145 stations. Data from most stations have multiple uses. All stations have sufficient justification for continuation, but two stations primarily are used in short-term research studies; their continued operation needs to be evaluated when the research studies end. The present measurement frequency produces an average standard error for instantaneous discharges of about 12 percent, including periods when stage data are missing. Altering the travel routes and the measurement frequency will allow a reduction in standard error of about 1 percent with the present budget. Standard error could be reduced to about 8 percent if lost record could be eliminated. A minimum budget of $822,000 is required to operate the present network, but operations at that funding level would result in an increase in standard error to about 16 percent. The maximum budget analyzed was $1,363,000, which would result in an average standard error of 6 percent. (USGS)

Evaluation of Stress and a Stress-Reduction Program Among Radiologic Technologists.

PubMed

Reingold, Lynn

2015-01-01

To investigate stress levels and causes of stress among radiologic technologists and determine whether an intervention could reduce stress in a selected radiologic technologist population. Demographic characteristics and data on preintervention stress sources and levels were collected through Internet-based questionnaires. A 6-week, self-administered, mindfulness-based stress-reduction program was conducted as a pilot intervention with 42 radiologic technologists from the Veterans Administration Medical Center. Data also were collected postintervention. Identified sources of stress were compared with findings from previous studies. Some radiologic technologists experienced improvement in their perceptions of stress after the intervention. Sources of stress for radiologic technologists were similar to those shown in earlier research, including inconsistent management, poor management communication, conflicting demands, long work hours, excessive workloads, lack of work breaks, and time pressures. The mindfulness-based stress-reduction program is an example of an inexpensive method that could improve personal well-being, reduce work errors, improve relationships in the workplace, and increase job satisfaction. More research is needed to determine the best type of intervention for stress reduction in a larger radiologic technologist population.

A Comprehensive Quality Assurance Program for Personnel and Procedures in Radiation Oncology: Value of Voluntary Error Reporting and Checklists

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalapurakal, John A., E-mail: j-kalapurakal@northwestern.edu; Zafirovski, Aleksandar; Smith, Jeffery

Purpose: This report describes the value of a voluntary error reporting system and the impact of a series of quality assurance (QA) measures including checklists and timeouts on reported error rates in patients receiving radiation therapy. Methods and Materials: A voluntary error reporting system was instituted with the goal of recording errors, analyzing their clinical impact, and guiding the implementation of targeted QA measures. In response to errors committed in relation to treatment of the wrong patient, wrong treatment site, and wrong dose, a novel initiative involving the use of checklists and timeouts for all staff was implemented. The impactmore » of these and other QA initiatives was analyzed. Results: From 2001 to 2011, a total of 256 errors in 139 patients after 284,810 external radiation treatments (0.09% per treatment) were recorded in our voluntary error database. The incidence of errors related to patient/tumor site, treatment planning/data transfer, and patient setup/treatment delivery was 9%, 40.2%, and 50.8%, respectively. The compliance rate for the checklists and timeouts initiative was 97% (P<.001). These and other QA measures resulted in a significant reduction in many categories of errors. The introduction of checklists and timeouts has been successful in eliminating errors related to wrong patient, wrong site, and wrong dose. Conclusions: A comprehensive QA program that regularly monitors staff compliance together with a robust voluntary error reporting system can reduce or eliminate errors that could result in serious patient injury. We recommend the adoption of these relatively simple QA initiatives including the use of checklists and timeouts for all staff to improve the safety of patients undergoing radiation therapy in the modern era.« less

Evaluation and analysis of the orbital maneuvering vehicle video system

NASA Technical Reports Server (NTRS)

Moorhead, Robert J., II

1989-01-01

The work accomplished in the summer of 1989 in association with the NASA/ASEE Summer Faculty Research Fellowship Program at Marshall Space Flight Center is summarized. The task involved study of the Orbital Maneuvering Vehicle (OMV) Video Compression Scheme. This included such activities as reviewing the expected scenes to be compressed by the flight vehicle, learning the error characteristics of the communication channel, monitoring the CLASS tests, and assisting in development of test procedures and interface hardware for the bit error rate lab being developed at MSFC to test the VCU/VRU. Numerous comments and suggestions were made during the course of the fellowship period regarding the design and testing of the OMV Video System. Unfortunately from a technical point of view, the program appears at this point in time to be trouble from an expense prospective and is in fact in danger of being scaled back, if not cancelled altogether. This makes technical improvements prohibitive and cost-reduction measures necessary. Fortunately some cost-reduction possibilities and some significant technical improvements that should cost very little were identified.

ATE accomplishes receiver specification testing with increased speed and throughput

NASA Astrophysics Data System (ADS)

Moser, S. A.

1982-12-01

The use of automatic test equipment (ATE) for receiver specifications testing can result in a 90-95% reduction of test time, with a corresponding reduction of labor costs due both to the reduction of personnel numbers and a simplification of tasks that permits less skilled personnel to be employed. These benefits free high-level technicians for more challenging system management assignments. Accuracy and repeatability also improve with the adoption of ATE, since no possibility of human error can be introduced into the readings that are taken by the system. A massive and expensive software design and development effort is identified as the most difficult aspect of ATE implementation, since programming is both time-consuming and labor intensive. An attempt is therefore made by system manufacturers to conduct an integrated development program for both ATE system hardware and software.

Error reduction program: A progress report

NASA Technical Reports Server (NTRS)

Syed, S. A.

1984-01-01

Five finite differences schemes were evaluated for minimum numerical diffusion in an effort to identify and incorporate the best error reduction scheme into a 3D combustor performance code. Based on this evaluated, two finite volume method schemes were selected for further study. Both the quadratic upstream differencing scheme (QUDS) and the bounded skew upstream differencing scheme two (BSUDS2) were coded into a two dimensional computer code and their accuracy and stability determined by running several test cases. It was found that BSUDS2 was more stable than QUDS. It was also found that the accuracy of both schemes is dependent on the angle that the streamline make with the mesh with QUDS being more accurate at smaller angles and BSUDS2 more accurate at larger angles. The BSUDS2 scheme was selected for extension into three dimensions.

Design and Stress Analysis of Low-Noise Adjusted Bearing Contact Spiral Bevel Gears

NASA Technical Reports Server (NTRS)

Fuentes, A.; Litvin, F. L.; Mullins, B. R.; Woods, R.; Handschuh, R. F.; Lewicki, David G.

2002-01-01

An integrated computerized approach for design and stress analysis of low-noise spiral bevel gear drives with adjusted bearing contact is proposed. The procedure of computations is an iterative process that requires four separate procedures and provide: (a) a parabolic function of transmission errors that is able to reduce the effect of errors of alignment on noise and vibration, and (b) reduction of the shift of bearing contact caused by misalignment. Application of finite element analysis enables us to determine the contact and bending stresses and investigate the formation of the bearing contact. The design of finite element models and boundary conditions is automated and does not require intermediate CAD computer programs for application of general purpose computer program for finite element analysis.

[Virtual surgical education: experience with medicine and surgery students].

PubMed

Bonavina, Luigi; Mozzi, Enrico; Peracchia, Alberto

2003-01-01

The use of virtual reality simulation is currently being proposed within programs of postgraduate surgical education. The simple tasks that make up an operative procedure can be repeatedly performed until satisfactory execution is achieved, and the errors can be corrected by means of objective assessment. The aim of this study was to evaluate the applicability and the results of structured practice with the LapSim laparoscopic simulator used by undergraduate medical students. A significant reduction in operative time and errors was noted in several tasks (navigation, clipping, etc.). Although the transfer of technical skills to the operating room environment remains to be demonstrated, our research shows that this type of teaching is applicable to undergraduate medical students and in future may become a useful tool for selecting individuals for surgical residency programs.

Mitigating errors caused by interruptions during medication verification and administration: interventions in a simulated ambulatory chemotherapy setting.

PubMed

Prakash, Varuna; Koczmara, Christine; Savage, Pamela; Trip, Katherine; Stewart, Janice; McCurdie, Tara; Cafazzo, Joseph A; Trbovich, Patricia

2014-11-01

Nurses are frequently interrupted during medication verification and administration; however, few interventions exist to mitigate resulting errors, and the impact of these interventions on medication safety is poorly understood. The study objectives were to (A) assess the effects of interruptions on medication verification and administration errors, and (B) design and test the effectiveness of targeted interventions at reducing these errors. The study focused on medication verification and administration in an ambulatory chemotherapy setting. A simulation laboratory experiment was conducted to determine interruption-related error rates during specific medication verification and administration tasks. Interventions to reduce these errors were developed through a participatory design process, and their error reduction effectiveness was assessed through a postintervention experiment. Significantly more nurses committed medication errors when interrupted than when uninterrupted. With use of interventions when interrupted, significantly fewer nurses made errors in verifying medication volumes contained in syringes (16/18; 89% preintervention error rate vs 11/19; 58% postintervention error rate; p=0.038; Fisher's exact test) and programmed in ambulatory pumps (17/18; 94% preintervention vs 11/19; 58% postintervention; p=0.012). The rate of error commission significantly decreased with use of interventions when interrupted during intravenous push (16/18; 89% preintervention vs 6/19; 32% postintervention; p=0.017) and pump programming (7/18; 39% preintervention vs 1/19; 5% postintervention; p=0.017). No statistically significant differences were observed for other medication verification tasks. Interruptions can lead to medication verification and administration errors. Interventions were highly effective at reducing unanticipated errors of commission in medication administration tasks, but showed mixed effectiveness at reducing predictable errors of detection in medication verification tasks. These findings can be generalised and adapted to mitigate interruption-related errors in other settings where medication verification and administration are required. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Mitigating errors caused by interruptions during medication verification and administration: interventions in a simulated ambulatory chemotherapy setting

PubMed Central

Prakash, Varuna; Koczmara, Christine; Savage, Pamela; Trip, Katherine; Stewart, Janice; McCurdie, Tara; Cafazzo, Joseph A; Trbovich, Patricia

2014-01-01

Background Nurses are frequently interrupted during medication verification and administration; however, few interventions exist to mitigate resulting errors, and the impact of these interventions on medication safety is poorly understood. Objective The study objectives were to (A) assess the effects of interruptions on medication verification and administration errors, and (B) design and test the effectiveness of targeted interventions at reducing these errors. Methods The study focused on medication verification and administration in an ambulatory chemotherapy setting. A simulation laboratory experiment was conducted to determine interruption-related error rates during specific medication verification and administration tasks. Interventions to reduce these errors were developed through a participatory design process, and their error reduction effectiveness was assessed through a postintervention experiment. Results Significantly more nurses committed medication errors when interrupted than when uninterrupted. With use of interventions when interrupted, significantly fewer nurses made errors in verifying medication volumes contained in syringes (16/18; 89% preintervention error rate vs 11/19; 58% postintervention error rate; p=0.038; Fisher's exact test) and programmed in ambulatory pumps (17/18; 94% preintervention vs 11/19; 58% postintervention; p=0.012). The rate of error commission significantly decreased with use of interventions when interrupted during intravenous push (16/18; 89% preintervention vs 6/19; 32% postintervention; p=0.017) and pump programming (7/18; 39% preintervention vs 1/19; 5% postintervention; p=0.017). No statistically significant differences were observed for other medication verification tasks. Conclusions Interruptions can lead to medication verification and administration errors. Interventions were highly effective at reducing unanticipated errors of commission in medication administration tasks, but showed mixed effectiveness at reducing predictable errors of detection in medication verification tasks. These findings can be generalised and adapted to mitigate interruption-related errors in other settings where medication verification and administration are required. PMID:24906806

Gait Speed among Older Participants Enrolled in an Evidence-Based Fall Risk Reduction Program: A Subgroup Analysis.

PubMed

Cho, Jinmyoung; Smith, Matthew Lee; Shubert, Tiffany E; Jiang, Luohua; Ahn, SangNam; Ory, Marcia G

2015-01-01

Functional decline is a primary risk factor for institutionalization and mortality among older adults. Although community-based fall risk reduction programs have been widely disseminated, little is known about their impact on gait speed, a key indicator of functional performance. Changes in functional performance between baseline and post-intervention were examined by means of timed up and go (TUG), a standardized functional assessment test administered to participants enrolled in A Matter of Balance/Volunteer Lay Leader (AMOB/VLL) model, an evidence-based fall risk reduction program. This study included 71 participants enrolled in an AMOB/VLL program in the Brazos Valley and South Plain regions of Texas. Paired t-tests were employed to assess program effects on gait speed at baseline and post-intervention for all participants and by subgroups of age, sex, living status, delivery sites, and self-rated health. The Bonferroni correction was applied to adjust inflated Type I error rate associated with performing multiple t-tests, for which p-values <0.0042 (i.e., 0.5/12 comparisons) were deemed statistically significant. Overall, gait speed of enrolled participants improved from baseline to post-intervention (t = 3.22, p = 0.002). Significant changes in TUG scores were observed among participants who lived with others (t = 4.45, p < 0.001), rated their health as excellent, very good, or good (t = 3.05, p = 0.003), and attended program workshops at senior centers (t = 3.52, p = 0.003). Findings suggest community-based fall risk reduction programs can improve gait speed for older adults. More translational research is needed to understand factors related to the effectiveness of fall risk reduction programs in various populations and settings.

Computerized Design and Generation of Low-Noise Gears with Localized Bearing Contact

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Chen, Ningxin; Chen, Jui-Sheng; Lu, Jian; Handschuh, Robert F.

1995-01-01

The results of research projects directed at the reduction of noise caused by misalignment of the following gear drives: double-circular arc helical gears, modified involute helical gears, face-milled spiral bevel gears, and face-milled formate cut hypoid gears are presented. Misalignment in these types of gear drives causes periodic, almost linear discontinuous functions of transmission errors. The period of such functions is the cycle of meshing when one pair of teeth is changed for the next. Due to the discontinuity of such functions of transmission errors high vibration and noise are inevitable. A predesigned parabolic function of transmission errors that is able to absorb linear discontinuous functions of transmission errors and change the resulting function of transmission errors into a continuous one is proposed. The proposed idea was successfully tested using spiral bevel gears and the noise was reduced a substantial amount in comparison with the existing design. The idea of a predesigned parabolic function is applied for the reduction of noise of helical and hypoid gears. The effectiveness of the proposed approach has been investigated by developed TCA (tooth contact analysis) programs. The bearing contact for the mentioned gears is localized. Conditions that avoid edge contact for the gear drives have been determined. Manufacturing of helical gears with new topology by hobs and grinding worms has been investigated.

Zero tolerance prescribing: a strategy to reduce prescribing errors on the paediatric intensive care unit.

PubMed

Booth, Rachelle; Sturgess, Emma; Taberner-Stokes, Alison; Peters, Mark

2012-11-01

To establish the baseline prescribing error rate in a tertiary paediatric intensive care unit (PICU) and to determine the impact of a zero tolerance prescribing (ZTP) policy incorporating a dedicated prescribing area and daily feedback of prescribing errors. A prospective, non-blinded, observational study was undertaken in a 12-bed tertiary PICU over a period of 134 weeks. Baseline prescribing error data were collected on weekdays for all patients for a period of 32 weeks, following which the ZTP policy was introduced. Daily error feedback was introduced after a further 12 months. Errors were sub-classified as 'clinical', 'non-clinical' and 'infusion prescription' errors and the effects of interventions considered separately. The baseline combined prescribing error rate was 892 (95 % confidence interval (CI) 765-1,019) errors per 1,000 PICU occupied bed days (OBDs), comprising 25.6 % clinical, 44 % non-clinical and 30.4 % infusion prescription errors. The combined interventions of ZTP plus daily error feedback were associated with a reduction in the combined prescribing error rate to 447 (95 % CI 389-504) errors per 1,000 OBDs (p < 0.0001), an absolute risk reduction of 44.5 % (95 % CI 40.8-48.0 %). Introduction of the ZTP policy was associated with a significant decrease in clinical and infusion prescription errors, while the introduction of daily error feedback was associated with a significant reduction in non-clinical prescribing errors. The combined interventions of ZTP and daily error feedback were associated with a significant reduction in prescribing errors in the PICU, in line with Department of Health requirements of a 40 % reduction within 5 years.

DCS-Neural-Network Program for Aircraft Control and Testing

NASA Technical Reports Server (NTRS)

Jorgensen, Charles C.

2006-01-01

A computer program implements a dynamic-cell-structure (DCS) artificial neural network that can perform such tasks as learning selected aerodynamic characteristics of an airplane from wind-tunnel test data and computing real-time stability and control derivatives of the airplane for use in feedback linearized control. A DCS neural network is one of several types of neural networks that can incorporate additional nodes in order to rapidly learn increasingly complex relationships between inputs and outputs. In the DCS neural network implemented by the present program, the insertion of nodes is based on accumulated error. A competitive Hebbian learning rule (a supervised-learning rule in which connection weights are adjusted to minimize differences between actual and desired outputs for training examples) is used. A Kohonen-style learning rule (derived from a relatively simple training algorithm, implements a Delaunay triangulation layout of neurons) is used to adjust node positions during training. Neighborhood topology determines which nodes are used to estimate new values. The network learns, starting with two nodes, and adds new nodes sequentially in locations chosen to maximize reductions in global error. At any given time during learning, the error becomes homogeneously distributed over all nodes.

Application of Avco data analysis and prediction techniques (ADAPT) to prediction of sunspot activity

NASA Technical Reports Server (NTRS)

Hunter, H. E.; Amato, R. A.

1972-01-01

The results are presented of the application of Avco Data Analysis and Prediction Techniques (ADAPT) to derivation of new algorithms for the prediction of future sunspot activity. The ADAPT derived algorithms show a factor of 2 to 3 reduction in the expected 2-sigma errors in the estimates of the 81-day running average of the Zurich sunspot numbers. The report presents: (1) the best estimates for sunspot cycles 20 and 21, (2) a comparison of the ADAPT performance with conventional techniques, and (3) specific approaches to further reduction in the errors of estimated sunspot activity and to recovery of earlier sunspot historical data. The ADAPT programs are used both to derive regression algorithm for prediction of the entire 11-year sunspot cycle from the preceding two cycles and to derive extrapolation algorithms for extrapolating a given sunspot cycle based on any available portion of the cycle.

Design and Stress Analysis of Low-Noise Adjusted Bearing Contact Spiral Bevel Gears

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Fuentes, Alfonso; Mullins, Baxter R.; Woods, Ron

2002-01-01

An integrated computerized approach for design and stress analysis of low-noise spiral bevel gear drives with adjusted bearing contact has been developed. The computation procedure is an iterative process, requiring four separate steps that provide: (a) a parabolic function of transmission errors that is able to reduce the effect of errors of alignment, and (b) reduction of the shift of bearing contact caused by misalignment. Application of finite element analysis permits the contact and bending stresses to be determined and investigate the formation of the bearing contact. The design of finite element models and boundary conditions is automated and does not require an intermediate CAD computer program. A commercially available finite element analysis computer program with contact capability was used to conduct the stress analysis. The theory developed is illustrated with numerical examples.

A-posteriori error estimation for second order mechanical systems

NASA Astrophysics Data System (ADS)

Ruiner, Thomas; Fehr, Jörg; Haasdonk, Bernard; Eberhard, Peter

2012-06-01

One important issue for the simulation of flexible multibody systems is the reduction of the flexible bodies degrees of freedom. As far as safety questions are concerned knowledge about the error introduced by the reduction of the flexible degrees of freedom is helpful and very important. In this work, an a-posteriori error estimator for linear first order systems is extended for error estimation of mechanical second order systems. Due to the special second order structure of mechanical systems, an improvement of the a-posteriori error estimator is achieved. A major advantage of the a-posteriori error estimator is that the estimator is independent of the used reduction technique. Therefore, it can be used for moment-matching based, Gramian matrices based or modal based model reduction techniques. The capability of the proposed technique is demonstrated by the a-posteriori error estimation of a mechanical system, and a sensitivity analysis of the parameters involved in the error estimation process is conducted.

Mathematical analysis study for radar data processing and enchancement. Part 2: Modeling of propagation path errors

NASA Technical Reports Server (NTRS)

James, R.; Brownlow, J. D.

1985-01-01

A study is performed under NASA contract to evaluate data from an AN/FPS-16 radar installed for support of flight programs at Dryden Flight Research Facility of NASA Ames Research Center. The purpose of this study is to provide information necessary for improving post-flight data reduction and knowledge of accuracy of derived radar quantities. Tracking data from six flights are analyzed. Noise and bias errors in raw tracking data are determined for each of the flights. A discussion of an altitude bias error during all of the tracking missions is included. This bias error is defined by utilizing pressure altitude measurements made during survey flights. Four separate filtering methods, representative of the most widely used optimal estimation techniques for enhancement of radar tracking data, are analyzed for suitability in processing both real-time and post-mission data. Additional information regarding the radar and its measurements, including typical noise and bias errors in the range and angle measurements, is also presented. This report is in two parts. This is part 2, a discussion of the modeling of propagation path errors.

Using Six Sigma to reduce medication errors in a home-delivery pharmacy service.

PubMed

Castle, Lon; Franzblau-Isaac, Ellen; Paulsen, Jim

2005-06-01

Medco Health Solutions, Inc. conducted a project to reduce medication errors in its home-delivery service, which is composed of eight prescription-processing pharmacies, three dispensing pharmacies, and six call-center pharmacies. Medco uses the Six Sigma methodology to reduce process variation, establish procedures to monitor the effectiveness of medication safety programs, and determine when these efforts do not achieve performance goals. A team reviewed the processes in home-delivery pharmacy and suggested strategies to improve the data-collection and medication-dispensing practices. A variety of improvement activities were implemented, including a procedure for developing, reviewing, and enhancing sound-alike/look-alike (SALA) alerts and system enhancements to improve processing consistency across the pharmacies. "External nonconformances" were reduced for several categories of medication errors, including wrong-drug selection (33%), wrong directions (49%), and SALA errors (69%). Control charts demonstrated evidence of sustained process improvement and actual reduction in specific medication error elements. Establishing a continuous quality improvement process to ensure that medication errors are minimized is critical to any health care organization providing medication services.

The Accreditation Council for Graduate Medical Education's limits on residents' work hours and patient safety. A study of resident experiences and perceptions before and after hours reductions.

PubMed

Jagsi, Reshma; Weinstein, Debra F; Shapiro, Jo; Kitch, Barrett T; Dorer, David; Weissman, Joel S

2008-03-10

Limiting resident work hours may improve patient safety, but unintended adverse effects are also possible. We sought to assess the impact of Accreditation Council for Graduate Medical Education resident work hour limits implemented on July 1, 2003, on resident experiences and perceptions regarding patient safety. All trainees in 76 accredited programs at 2 teaching hospitals were surveyed in 2003 (preimplementation) and 2004 (postimplementation) regarding their work hours and patient load; perceived relation of work hours, patient load, and fatigue to patient safety; and experiences with adverse events and medical errors. Based on reported weekly duty hours, 13 programs experiencing substantial hours reductions were classified into a "reduced-hours" group. Change scores in outcome measures before and after policy implementation in the reduced-hours programs were compared with those in "other programs" to control for temporal trends, using 2-way analysis of variance with interaction. A total of 1770 responses were obtained (response rate, 60.0%). Analysis was restricted to 1498 responses from respondents in clinical years of training. Residents in the reduced-hours group reported significant reductions in mean weekly duty hours (from 76.6 to 68.0 hours, P < .001), and the percentage working more than 80 hours per week decreased from 44.0% to 16.6% (P < .001). No significant increases in patient load while on call (patients admitted, covered, or cross covered) were observed. Between 2003 and 2004, there was a decrease in the proportion of residents in the reduced-hours programs indicating that working too many hours (63.2% vs 44.0%; P < .001) or cross covering too many patients (65.9% vs 46.9%; P = .001) contributed to mistakes in patient care. There were no significant reductions in these 2 measures in the other group, and the differences in differences were significant (P = .03 and P = .02, respectively). The number of residents in reduced-hours programs who reported committing at least 1 medical error within the past week remained high in both study years (32.9% in 2003 and 26.3% in 2004, P = .27). It is possible to reduce residents' hours without increasing patient load. Doing so may reduce the extent to which fatigue affects patient safety as perceived by these frontline providers.

Medication errors in paediatric care: a systematic review of epidemiology and an evaluation of evidence supporting reduction strategy recommendations

PubMed Central

Miller, Marlene R; Robinson, Karen A; Lubomski, Lisa H; Rinke, Michael L; Pronovost, Peter J

2007-01-01

Background Although children are at the greatest risk for medication errors, little is known about the overall epidemiology of these errors, where the gaps are in our knowledge, and to what extent national medication error reduction strategies focus on children. Objective To synthesise peer reviewed knowledge on children's medication errors and on recommendations to improve paediatric medication safety by a systematic literature review. Data sources PubMed, Embase and Cinahl from 1 January 2000 to 30 April 2005, and 11 national entities that have disseminated recommendations to improve medication safety. Study selection Inclusion criteria were peer reviewed original data in English language. Studies that did not separately report paediatric data were excluded. Data extraction Two reviewers screened articles for eligibility and for data extraction, and screened all national medication error reduction strategies for relevance to children. Data synthesis From 358 articles identified, 31 were included for data extraction. The definition of medication error was non‐uniform across the studies. Dispensing and administering errors were the most poorly and non‐uniformly evaluated. Overall, the distributional epidemiological estimates of the relative percentages of paediatric error types were: prescribing 3–37%, dispensing 5–58%, administering 72–75%, and documentation 17–21%. 26 unique recommendations for strategies to reduce medication errors were identified; none were based on paediatric evidence. Conclusions Medication errors occur across the entire spectrum of prescribing, dispensing, and administering, are common, and have a myriad of non‐evidence based potential reduction strategies. Further research in this area needs a firmer standardisation for items such as dose ranges and definitions of medication errors, broader scope beyond inpatient prescribing errors, and prioritisation of implementation of medication error reduction strategies. PMID:17403758

Asymmetric programming: a highly reliable metadata allocation strategy for MLC NAND flash memory-based sensor systems.

PubMed

Huang, Min; Liu, Zhaoqing; Qiao, Liyan

2014-10-10

While the NAND flash memory is widely used as the storage medium in modern sensor systems, the aggressive shrinking of process geometry and an increase in the number of bits stored in each memory cell will inevitably degrade the reliability of NAND flash memory. In particular, it's critical to enhance metadata reliability, which occupies only a small portion of the storage space, but maintains the critical information of the file system and the address translations of the storage system. Metadata damage will cause the system to crash or a large amount of data to be lost. This paper presents Asymmetric Programming, a highly reliable metadata allocation strategy for MLC NAND flash memory storage systems. Our technique exploits for the first time the property of the multi-page architecture of MLC NAND flash memory to improve the reliability of metadata. The basic idea is to keep metadata in most significant bit (MSB) pages which are more reliable than least significant bit (LSB) pages. Thus, we can achieve relatively low bit error rates for metadata. Based on this idea, we propose two strategies to optimize address mapping and garbage collection. We have implemented Asymmetric Programming on a real hardware platform. The experimental results show that Asymmetric Programming can achieve a reduction in the number of page errors of up to 99.05% with the baseline error correction scheme.

St Elsewhere's or St Everywhere's: improving patient throughput in the private hospital sector.

PubMed

Laffey, Jennifer A; Wasson, Moran

2007-01-01

Communication errors have been found to be most common root cause of medical errors by the US-based Agency for Healthcare Research and Quality [1]. Although elective admissions to hospital involves a high volume of important healthcare communications where incorrect, missing or illegible information could result in a serious medical error, there is little published research on the impact of improving pre-admission communication flow between admitting doctors and hospitals. The Sydney Adventist Hospital (the San) is a 341-bed private hospital in Sydney's northern suburbs that provides a comprehensive range of health services. A process improvement program began in early 2005 to streamline preadmission communications. The objectives of this ongoing program are broadly to improve patient safety and to increase operating efficiency. The first major initiative within this program was to implement a standardised method for inpatient booking/referral with over three hundred admitting doctors. Eighteen months on, the hospital has been able to demonstrate a significant shift in the timeliness of patient bookings from specialists' rooms, more comprehensive provision of clinical indicators that can facilitate resource planning in operating theatres and on the wards, and reduction in the ratio of bookings made in areas other than the hospital bookings department. The program continues with focus on improving accuracy of data entry, rationalising patient forms, making more effective use of information received and automation of pre-admission information flows.

Asymmetric Programming: A Highly Reliable Metadata Allocation Strategy for MLC NAND Flash Memory-Based Sensor Systems

PubMed Central

Huang, Min; Liu, Zhaoqing; Qiao, Liyan

2014-01-01

While the NAND flash memory is widely used as the storage medium in modern sensor systems, the aggressive shrinking of process geometry and an increase in the number of bits stored in each memory cell will inevitably degrade the reliability of NAND flash memory. In particular, it's critical to enhance metadata reliability, which occupies only a small portion of the storage space, but maintains the critical information of the file system and the address translations of the storage system. Metadata damage will cause the system to crash or a large amount of data to be lost. This paper presents Asymmetric Programming, a highly reliable metadata allocation strategy for MLC NAND flash memory storage systems. Our technique exploits for the first time the property of the multi-page architecture of MLC NAND flash memory to improve the reliability of metadata. The basic idea is to keep metadata in most significant bit (MSB) pages which are more reliable than least significant bit (LSB) pages. Thus, we can achieve relatively low bit error rates for metadata. Based on this idea, we propose two strategies to optimize address mapping and garbage collection. We have implemented Asymmetric Programming on a real hardware platform. The experimental results show that Asymmetric Programming can achieve a reduction in the number of page errors of up to 99.05% with the baseline error correction scheme. PMID:25310473

Rates of medical errors and preventable adverse events among hospitalized children following implementation of a resident handoff bundle.

PubMed

Starmer, Amy J; Sectish, Theodore C; Simon, Dennis W; Keohane, Carol; McSweeney, Maireade E; Chung, Erica Y; Yoon, Catherine S; Lipsitz, Stuart R; Wassner, Ari J; Harper, Marvin B; Landrigan, Christopher P

2013-12-04

Handoff miscommunications are a leading cause of medical errors. Studies comprehensively assessing handoff improvement programs are lacking. To determine whether introduction of a multifaceted handoff program was associated with reduced rates of medical errors and preventable adverse events, fewer omissions of key data in written handoffs, improved verbal handoffs, and changes in resident-physician workflow. Prospective intervention study of 1255 patient admissions (642 before and 613 after the intervention) involving 84 resident physicians (42 before and 42 after the intervention) from July-September 2009 and November 2009-January 2010 on 2 inpatient units at Boston Children's Hospital. Resident handoff bundle, consisting of standardized communication and handoff training, a verbal mnemonic, and a new team handoff structure. On one unit, a computerized handoff tool linked to the electronic medical record was introduced. The primary outcomes were the rates of medical errors and preventable adverse events measured by daily systematic surveillance. The secondary outcomes were omissions in the printed handoff document and resident time-motion activity. Medical errors decreased from 33.8 per 100 admissions (95% CI, 27.3-40.3) to 18.3 per 100 admissions (95% CI, 14.7-21.9; P < .001), and preventable adverse events decreased from 3.3 per 100 admissions (95% CI, 1.7-4.8) to 1.5 (95% CI, 0.51-2.4) per 100 admissions (P = .04) following the intervention. There were fewer omissions of key handoff elements on printed handoff documents, especially on the unit that received the computerized handoff tool (significant reductions of omissions in 11 of 14 categories with computerized tool; significant reductions in 2 of 14 categories without computerized tool). Physicians spent a greater percentage of time in a 24-hour period at the patient bedside after the intervention (8.3%; 95% CI 7.1%-9.8%) vs 10.6% (95% CI, 9.2%-12.2%; P = .03). The average duration of verbal handoffs per patient did not change. Verbal handoffs were more likely to occur in a quiet location (33.3%; 95% CI, 14.5%-52.2% vs 67.9%; 95% CI, 50.6%-85.2%; P = .03) and private location (50.0%; 95% CI, 30%-70% vs 85.7%; 95% CI, 72.8%-98.7%; P = .007) after the intervention. Implementation of a handoff bundle was associated with a significant reduction in medical errors and preventable adverse events among hospitalized children. Improvements in verbal and written handoff processes occurred, and resident workflow did not change adversely.

Ionospheric Modeling: Development, Verification and Validation

DTIC Science & Technology

2007-08-15

The University of Massachusetts (UMass), Lowell, has introduced a new version of their ionogram autoscaling program ARTIST , Version 5. A very...Investigation of the Reliability of the ESIR Ionogram Autoscaling Method (Expert System for Ionogram Reduction) ESIR.book.pdf Dec 06 Quality...Figures and Error Bars for Autoscaled Vertical Incidence Ionograms. Background and User Documentation for QualScan V2007.2 AFRL_QualScan.book.pdf Feb

Minimizing treatment planning errors in proton therapy using failure mode and effects analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Yuanshui, E-mail: yuanshui.zheng@okc.procure.com; Johnson, Randall; Larson, Gary

Purpose: Failure mode and effects analysis (FMEA) is a widely used tool to evaluate safety or reliability in conventional photon radiation therapy. However, reports about FMEA application in proton therapy are scarce. The purpose of this study is to apply FMEA in safety improvement of proton treatment planning at their center. Methods: The authors performed an FMEA analysis of their proton therapy treatment planning process using uniform scanning proton beams. The authors identified possible failure modes in various planning processes, including image fusion, contouring, beam arrangement, dose calculation, plan export, documents, billing, and so on. For each error, the authorsmore » estimated the frequency of occurrence, the likelihood of being undetected, and the severity of the error if it went undetected and calculated the risk priority number (RPN). The FMEA results were used to design their quality management program. In addition, the authors created a database to track the identified dosimetric errors. Periodically, the authors reevaluated the risk of errors by reviewing the internal error database and improved their quality assurance program as needed. Results: In total, the authors identified over 36 possible treatment planning related failure modes and estimated the associated occurrence, detectability, and severity to calculate the overall risk priority number. Based on the FMEA, the authors implemented various safety improvement procedures into their practice, such as education, peer review, and automatic check tools. The ongoing error tracking database provided realistic data on the frequency of occurrence with which to reevaluate the RPNs for various failure modes. Conclusions: The FMEA technique provides a systematic method for identifying and evaluating potential errors in proton treatment planning before they result in an error in patient dose delivery. The application of FMEA framework and the implementation of an ongoing error tracking system at their clinic have proven to be useful in error reduction in proton treatment planning, thus improving the effectiveness and safety of proton therapy.« less

Minimizing treatment planning errors in proton therapy using failure mode and effects analysis.

PubMed

Zheng, Yuanshui; Johnson, Randall; Larson, Gary

2016-06-01

Failure mode and effects analysis (FMEA) is a widely used tool to evaluate safety or reliability in conventional photon radiation therapy. However, reports about FMEA application in proton therapy are scarce. The purpose of this study is to apply FMEA in safety improvement of proton treatment planning at their center. The authors performed an FMEA analysis of their proton therapy treatment planning process using uniform scanning proton beams. The authors identified possible failure modes in various planning processes, including image fusion, contouring, beam arrangement, dose calculation, plan export, documents, billing, and so on. For each error, the authors estimated the frequency of occurrence, the likelihood of being undetected, and the severity of the error if it went undetected and calculated the risk priority number (RPN). The FMEA results were used to design their quality management program. In addition, the authors created a database to track the identified dosimetric errors. Periodically, the authors reevaluated the risk of errors by reviewing the internal error database and improved their quality assurance program as needed. In total, the authors identified over 36 possible treatment planning related failure modes and estimated the associated occurrence, detectability, and severity to calculate the overall risk priority number. Based on the FMEA, the authors implemented various safety improvement procedures into their practice, such as education, peer review, and automatic check tools. The ongoing error tracking database provided realistic data on the frequency of occurrence with which to reevaluate the RPNs for various failure modes. The FMEA technique provides a systematic method for identifying and evaluating potential errors in proton treatment planning before they result in an error in patient dose delivery. The application of FMEA framework and the implementation of an ongoing error tracking system at their clinic have proven to be useful in error reduction in proton treatment planning, thus improving the effectiveness and safety of proton therapy.

Errors in laboratory medicine: practical lessons to improve patient safety.

PubMed

Howanitz, Peter J

2005-10-01

Patient safety is influenced by the frequency and seriousness of errors that occur in the health care system. Error rates in laboratory practices are collected routinely for a variety of performance measures in all clinical pathology laboratories in the United States, but a list of critical performance measures has not yet been recommended. The most extensive databases describing error rates in pathology were developed and are maintained by the College of American Pathologists (CAP). These databases include the CAP's Q-Probes and Q-Tracks programs, which provide information on error rates from more than 130 interlaboratory studies. To define critical performance measures in laboratory medicine, describe error rates of these measures, and provide suggestions to decrease these errors, thereby ultimately improving patient safety. A review of experiences from Q-Probes and Q-Tracks studies supplemented with other studies cited in the literature. Q-Probes studies are carried out as time-limited studies lasting 1 to 4 months and have been conducted since 1989. In contrast, Q-Tracks investigations are ongoing studies performed on a yearly basis and have been conducted only since 1998. Participants from institutions throughout the world simultaneously conducted these studies according to specified scientific designs. The CAP has collected and summarized data for participants about these performance measures, including the significance of errors, the magnitude of error rates, tactics for error reduction, and willingness to implement each of these performance measures. A list of recommended performance measures, the frequency of errors when these performance measures were studied, and suggestions to improve patient safety by reducing these errors. Error rates for preanalytic and postanalytic performance measures were higher than for analytic measures. Eight performance measures were identified, including customer satisfaction, test turnaround times, patient identification, specimen acceptability, proficiency testing, critical value reporting, blood product wastage, and blood culture contamination. Error rate benchmarks for these performance measures were cited and recommendations for improving patient safety presented. Not only has each of the 8 performance measures proven practical, useful, and important for patient care, taken together, they also fulfill regulatory requirements. All laboratories should consider implementing these performance measures and standardizing their own scientific designs, data analysis, and error reduction strategies according to findings from these published studies.

A greedy algorithm for species selection in dimension reduction of combustion chemistry

NASA Astrophysics Data System (ADS)

Hiremath, Varun; Ren, Zhuyin; Pope, Stephen B.

2010-09-01

Computational calculations of combustion problems involving large numbers of species and reactions with a detailed description of the chemistry can be very expensive. Numerous dimension reduction techniques have been developed in the past to reduce the computational cost. In this paper, we consider the rate controlled constrained-equilibrium (RCCE) dimension reduction method, in which a set of constrained species is specified. For a given number of constrained species, the 'optimal' set of constrained species is that which minimizes the dimension reduction error. The direct determination of the optimal set is computationally infeasible, and instead we present a greedy algorithm which aims at determining a 'good' set of constrained species; that is, one leading to near-minimal dimension reduction error. The partially-stirred reactor (PaSR) involving methane premixed combustion with chemistry described by the GRI-Mech 1.2 mechanism containing 31 species is used to test the algorithm. Results on dimension reduction errors for different sets of constrained species are presented to assess the effectiveness of the greedy algorithm. It is shown that the first four constrained species selected using the proposed greedy algorithm produce lower dimension reduction error than constraints on the major species: CH4, O2, CO2 and H2O. It is also shown that the first ten constrained species selected using the proposed greedy algorithm produce a non-increasing dimension reduction error with every additional constrained species; and produce the lowest dimension reduction error in many cases tested over a wide range of equivalence ratios, pressures and initial temperatures.

Model-Based Optimal Experimental Design for Complex Physical Systems

DTIC Science & Technology

2015-12-03

for public release. magnitude reduction in estimator error required to make solving the exact optimal design problem tractable. Instead of using a naive...for designing a sequence of experiments uses suboptimal approaches: batch design that has no feedback, or greedy ( myopic ) design that optimally...approved for public release. Equation 1 is difficult to solve directly, but can be expressed in an equivalent form using the principle of dynamic programming

Results of the long range position-determining system tests. [Field Army system

NASA Technical Reports Server (NTRS)

Rhode, F. W.

1973-01-01

The long range position-determining system (LRPDS) has been developed by the Corps of Engineers to provide the Field Army with a rapid and accurate positioning capability. The LRPDS consists of an airborne reference position set (RPS), up to 30 ground based positioning sets (PS), and a position computing central (PCC). The PCC calculates the position of each PS based on the range change information provided by each Set. The positions can be relayed back to the PS again via RPS. Each PS unit contains a double oven precise crystal oscillator. The RPS contains a Hewlett-Packard cesium beam standard. Frequency drifts and off-sets of the crystal oscillators are taken in account in the data reduction process. A field test program was initiated in November 1972. A total of 54 flights were made which included six flights for equipment testing and 48 flights utilizing the field test data reduction program. The four general types of PS layouts used were: short range; medium range; long range; tactical configuration. The overall RMS radial error of the unknown positions varied from about 2.3 meters for the short range to about 15 meters for the long range. The corresponding elevation RMS errors vary from about 12 meters to 37 meters.

Common and Dissociable Neural Activity After Mindfulness-Based Stress Reduction and Relaxation Response Programs.

PubMed

Sevinc, Gunes; Hölzel, Britta K; Hashmi, Javeria; Greenberg, Jonathan; McCallister, Adrienne; Treadway, Michael; Schneider, Marissa L; Dusek, Jeffery A; Carmody, James; Lazar, Sara W

2018-06-01

We investigated common and dissociable neural and psychological correlates of two widely used meditation-based stress reduction programs. Participants were randomized to the Relaxation Response (RR; n = 18; 56% female) or the Mindfulness-Based Stress Reduction (MBSR; n = 16; 56% female) programs. Both programs use a "bodyscan" meditation; however, the RR program explicitly emphasizes physical relaxation during this practice, whereas the MBSR program emphasizes mindful awareness with no explicit relaxation instructions. After the programs, neural activity during the respective meditation was investigated using functional magnetic resonance imaging. Both programs were associated with reduced stress (for RR, from 14.1 ± 6.6 to 11.3 ± 5.5 [Cohen's d = 0.50; for MBSR, from 17.7 ± 5.7 to 11.9 ± 5.0 [Cohen's d = 1.02]). Conjunction analyses revealed functional coupling between ventromedial prefrontal regions and supplementary motor areas (p < .001). The disjunction analysis indicated that the RR bodyscan was associated with stronger functional connectivity of the right inferior frontal gyrus-an important hub of intentional inhibition and control-with supplementary motor areas (p < .001, family-wise error [FWE] rate corrected). The MBSR program was uniquely associated with improvements in self-compassion and rumination, and the within-group analysis of MBSR bodyscan revealed significant functional connectivity of the right anterior insula-an important hub of sensory awareness and salience-with pregenual anterior cingulate during bodyscan meditation compared with rest (p = .03, FWE corrected). The bodyscan exercises in each program were associated with both overlapping and differential functional coupling patterns, which were consistent with each program's theoretical foundation. These results may have implications for the differential effects of these programs for the treatment of diverse conditions.

Reduction of Maintenance Error Through Focused Interventions

NASA Technical Reports Server (NTRS)

Kanki, Barbara G.; Walter, Diane; Rosekind, Mark R. (Technical Monitor)

1997-01-01

It is well known that a significant proportion of aviation accidents and incidents are tied to human error. In flight operations, research of operational errors has shown that so-called "pilot error" often involves a variety of human factors issues and not a simple lack of individual technical skills. In aircraft maintenance operations, there is similar concern that maintenance errors which may lead to incidents and accidents are related to a large variety of human factors issues. Although maintenance error data and research are limited, industry initiatives involving human factors training in maintenance have become increasingly accepted as one type of maintenance error intervention. Conscientious efforts have been made in re-inventing the "team" concept for maintenance operations and in tailoring programs to fit the needs of technical operations. Nevertheless, there remains a dual challenge: to develop human factors interventions which are directly supported by reliable human error data, and to integrate human factors concepts into the procedures and practices of everyday technical tasks. In this paper, we describe several varieties of human factors interventions and focus on two specific alternatives which target problems related to procedures and practices; namely, 1) structured on-the-job training and 2) procedure re-design. We hope to demonstrate that the key to leveraging the impact of these solutions comes from focused interventions; that is, interventions which are derived from a clear understanding of specific maintenance errors, their operational context and human factors components.

Medical Errors Reduction Initiative

DTIC Science & Technology

2005-05-01

working with great success to minimize error. 14. SUBJECT TERMS 15. NUMBER OF PAGES Medical Error, Patient Safety, Personal Data Terminal, Barcodes, 9...AD Award Number: W81XWH-04-1-0536 TITLE: Medical Errors Reduction Initiative PRINCIPAL INVESTIGATOR: Michael L. Mutter 1To CONTRACTING ORGANIZATION...The Valley Hospital Ridgewood, NJ 07450 REPORT DATE: May 2005 TYPE OF REPORT: Annual PREPARED FOR: U.S. Army Medical Research and Materiel Command

The Canonical Robot Command Language (CRCL).

PubMed

Proctor, Frederick M; Balakirsky, Stephen B; Kootbally, Zeid; Kramer, Thomas R; Schlenoff, Craig I; Shackleford, William P

2016-01-01

Industrial robots can perform motion with sub-millimeter repeatability when programmed using the teach-and-playback method. While effective, this method requires significant up-front time, tying up the robot and a person during the teaching phase. Off-line programming can be used to generate robot programs, but the accuracy of this method is poor unless supplemented with good calibration to remove systematic errors, feed-forward models to anticipate robot response to loads, and sensing to compensate for unmodeled errors. These increase the complexity and up-front cost of the system, but the payback in the reduction of recurring teach programming time can be worth the effort. This payback especially benefits small-batch, short-turnaround applications typical of small-to-medium enterprises, who need the agility afforded by off-line application development to be competitive against low-cost manual labor. To fully benefit from this agile application tasking model, a common representation of tasks should be used that is understood by all of the resources required for the job: robots, tooling, sensors, and people. This paper describes an information model, the Canonical Robot Command Language (CRCL), which provides a high-level description of robot tasks and associated control and status information.

The Canonical Robot Command Language (CRCL)

PubMed Central

Proctor, Frederick M.; Balakirsky, Stephen B.; Kootbally, Zeid; Kramer, Thomas R.; Schlenoff, Craig I.; Shackleford, William P.

2017-01-01

Industrial robots can perform motion with sub-millimeter repeatability when programmed using the teach-and-playback method. While effective, this method requires significant up-front time, tying up the robot and a person during the teaching phase. Off-line programming can be used to generate robot programs, but the accuracy of this method is poor unless supplemented with good calibration to remove systematic errors, feed-forward models to anticipate robot response to loads, and sensing to compensate for unmodeled errors. These increase the complexity and up-front cost of the system, but the payback in the reduction of recurring teach programming time can be worth the effort. This payback especially benefits small-batch, short-turnaround applications typical of small-to-medium enterprises, who need the agility afforded by off-line application development to be competitive against low-cost manual labor. To fully benefit from this agile application tasking model, a common representation of tasks should be used that is understood by all of the resources required for the job: robots, tooling, sensors, and people. This paper describes an information model, the Canonical Robot Command Language (CRCL), which provides a high-level description of robot tasks and associated control and status information. PMID:28529393

Stitching-error reduction in gratings by shot-shifted electron-beam lithography

NASA Technical Reports Server (NTRS)

Dougherty, D. J.; Muller, R. E.; Maker, P. D.; Forouhar, S.

2001-01-01

Calculations of the grating spatial-frequency spectrum and the filtering properties of multiple-pass electron-beam writing demonstrate a tradeoff between stitching-error suppression and minimum pitch separation. High-resolution measurements of optical-diffraction patterns show a 25-dB reduction in stitching-error side modes.

Evaluation of a parallel implementation of the learning portion of the backward error propagation neural network: experiments in artifact identification.

PubMed Central

Sittig, D. F.; Orr, J. A.

1991-01-01

Various methods have been proposed in an attempt to solve problems in artifact and/or alarm identification including expert systems, statistical signal processing techniques, and artificial neural networks (ANN). ANNs consist of a large number of simple processing units connected by weighted links. To develop truly robust ANNs, investigators are required to train their networks on huge training data sets, requiring enormous computing power. We implemented a parallel version of the backward error propagation neural network training algorithm in the widely portable parallel programming language C-Linda. A maximum speedup of 4.06 was obtained with six processors. This speedup represents a reduction in total run-time from approximately 6.4 hours to 1.5 hours. We conclude that use of the master-worker model of parallel computation is an excellent method for obtaining speedups in the backward error propagation neural network training algorithm. PMID:1807607

Reduction of low frequency error for SED36 and APS based HYDRA star trackers

NASA Astrophysics Data System (ADS)

Ouaknine, Julien; Blarre, Ludovic; Oddos-Marcel, Lionel; Montel, Johan; Julio, Jean-Marc

2017-11-01

In the frame of the CNES Pleiades satellite, a reduction of the star tracker low frequency error, which is the most penalizing error for the satellite attitude control, was performed. For that purpose, the SED36 star tracker was developed, with a design based on the flight qualified SED16/26. In this paper, the SED36 main features will be first presented. Then, the reduction process of the low frequency error will be developed, particularly the optimization of the optical distortion calibration. The result is an attitude low frequency error of 1.1" at 3 sigma along transverse axes. The implementation of these improvements to HYDRA, the new multi-head APS star tracker developed by SODERN, will finally be presented.

A pilot study of the utility of a laboratory-based spinal fixation training program for neurosurgical residents.

PubMed

Sundar, Swetha J; Healy, Andrew T; Kshettry, Varun R; Mroz, Thomas E; Schlenk, Richard; Benzel, Edward C

2016-05-01

OBJECTIVE Pedicle and lateral mass screw placement is technically demanding due to complex 3D spinal anatomy that is not easily visualized. Neurosurgical and orthopedic surgery residents must be properly trained in such procedures, which can be associated with significant complications and associated morbidity. Current training in pedicle and lateral mass screw placement involves didactic teaching and supervised placement in the operating room. The objective of this study was to assess whether teaching residents to place pedicle and lateral mass screws using navigation software, combined with practice using cadaveric specimens and Sawbones models, would improve screw placement accuracy. METHODS This was a single-blinded, prospective, randomized pilot study with 8 junior neurosurgical residents and 2 senior medical students with prior neurosurgery exposure. Both the study group and the level of training-matched control group (each group with 4 level of training-matched residents and 1 senior medical student) were exposed to a standardized didactic education regarding spinal anatomy and screw placement techniques. The study group was exposed to an additional pilot program that included a training session using navigation software combined with cadaveric specimens and accessibility to Sawbones models. RESULTS A statistically significant reduction in overall surgical error was observed in the study group compared with the control group (p = 0.04). Analysis by spinal region demonstrated a significant reduction in surgical error in the thoracic and lumbar regions in the study group compared with controls (p = 0.02 and p = 0.04, respectively). The study group also was observed to place screws more optimally in the cervical, thoracic, and lumbar regions (p = 0.02, p = 0.04, and p = 0.04, respectively). CONCLUSIONS Surgical resident education in pedicle and lateral mass screw placement is a priority for training programs. This study demonstrated that compared with a didactic-only training model, using navigation simulation with cadavers and Sawbones models significantly reduced the number of screw placement errors in a laboratory setting.

Flight Test Results of a GPS-Based Pitot-Static Calibration Method Using Output-Error Optimization for a Light Twin-Engine Airplane

NASA Technical Reports Server (NTRS)

Martos, Borja; Kiszely, Paul; Foster, John V.

2011-01-01

As part of the NASA Aviation Safety Program (AvSP), a novel pitot-static calibration method was developed to allow rapid in-flight calibration for subscale aircraft while flying within confined test areas. This approach uses Global Positioning System (GPS) technology coupled with modern system identification methods that rapidly computes optimal pressure error models over a range of airspeed with defined confidence bounds. This method has been demonstrated in subscale flight tests and has shown small 2- error bounds with significant reduction in test time compared to other methods. The current research was motivated by the desire to further evaluate and develop this method for full-scale aircraft. A goal of this research was to develop an accurate calibration method that enables reductions in test equipment and flight time, thus reducing costs. The approach involved analysis of data acquisition requirements, development of efficient flight patterns, and analysis of pressure error models based on system identification methods. Flight tests were conducted at The University of Tennessee Space Institute (UTSI) utilizing an instrumented Piper Navajo research aircraft. In addition, the UTSI engineering flight simulator was used to investigate test maneuver requirements and handling qualities issues associated with this technique. This paper provides a summary of piloted simulation and flight test results that illustrates the performance and capabilities of the NASA calibration method. Discussion of maneuver requirements and data analysis methods is included as well as recommendations for piloting technique.

An alternative to Guyan reduction of finite-element models

NASA Technical Reports Server (NTRS)

Lin, Jiguan Gene

1988-01-01

Structural modeling is a key part of structural system identification for large space structures. Finite-element structural models are commonly used in practice because of their general applicability and availability. The initial models generated by using a standard computer program such as NASTRAN, ANSYS, SUPERB, STARDYNE, STRUDL, etc., generally contain tens of thousands of degrees of freedom. The models must be reduced for purposes of identification. Not only does the magnitude of the identification effort grow exponentially as a function of the number of degrees of freedom, but numerical procedures may also break down because of accumulated round-off errors. Guyan reduction is usually applied after a static condensation. Misapplication of Guyan reduction can lead to serious modeling errors. It is quite unfortunate and disappointing, since the accuracy of the original detailed finite-element model one tries very hard to achieve is lost by the reduction. First, why and how Guyan reduction always causes loss of accuracy is examined. An alternative approach is then introduced. The alternative can be thought of as an improvement of Guyan reduction, the Rayleigh-Ritz method, and in particular the recent algorithm of Wilson, Yuan, and Dickens. Unlike Guyan reduction, the use of the alternative does not need any special insight, experience, or skill for partitioning the structural degrees of freedom. In addition to model condensation, this alternative approach can also be used for predicting analytically, quickly, and economically, what are those structural modes that are excitable by a force actuator at a given trial location. That is, in the excitation of the structural modes for identification, it can be used for guiding the placement of the force actuators.

The District Nursing Clinical Error Reduction Programme.

PubMed

McGraw, Caroline; Topping, Claire

2011-01-01

The District Nursing Clinical Error Reduction (DANCER) Programme was initiated in NHS Islington following an increase in the number of reported medication errors. The objectives were to reduce the actual degree of harm and the potential risk of harm associated with medication errors and to maintain the existing positive reporting culture, while robustly addressing performance issues. One hundred medication errors reported in 2007/08 were analysed using a framework that specifies the factors that predispose to adverse medication events in domiciliary care. Various contributory factors were identified and interventions were subsequently developed to address poor drug calculation and medication problem-solving skills and incorrectly transcribed medication administration record charts. Follow up data were obtained at 12 months and two years. The evaluation has shown that although medication errors do still occur, the programme has resulted in a marked shift towards a reduction in the associated actual degree of harm and the potential risk of harm.

Comparison of reduction of edema after rest and after muscle exercises in treatment of chronic venous insufficiency

PubMed Central

Quilici, Belczak Cleusa Ema; Gildo, Cavalheri; de Godoy, Jose Maria Pereira; Quilici, Belczak Sergio; Augusto, Caffaro Roberto

2009-01-01

Aim The aim of this work was to compare the reduction in edema obtained in the conservative treatment of phlebopathies after resting and after performing a muscle exercise program in the Trendelenburg position. Methods Twenty-eight limbs of 24 patients with venous edema of distinct etiologies and classified as between C3 and C5 using CEAP classification. Volumetric evaluation by water displacement was carried out before and after resting in the Trendelenburg position and after performing programmed muscle exercises 24 hours later under identical conditions of time, position and temperature. For the statistical analysis the paired t-test was used with an alpha error of 5% being considered acceptable. Results The average total volume of the lower limbs was 3,967.46 mL. The mean reduction in edema obtained after resting was 92.9 mL, and after exercises it was 135.4 mL, giving a statistically significant difference (p-value = 0.0007). Conclusion In conclusion, exercises are more efficient to reduce the edema of lower limbs than resting in the Trendelenburg position. PMID:19602249

Error Reduction Program. [combustor performance evaluation codes

NASA Technical Reports Server (NTRS)

Syed, S. A.; Chiappetta, L. M.; Gosman, A. D.

1985-01-01

The details of a study to select, incorporate and evaluate the best available finite difference scheme to reduce numerical error in combustor performance evaluation codes are described. The combustor performance computer programs chosen were the two dimensional and three dimensional versions of Pratt & Whitney's TEACH code. The criteria used to select schemes required that the difference equations mirror the properties of the governing differential equation, be more accurate than the current hybrid difference scheme, be stable and economical, be compatible with TEACH codes, use only modest amounts of additional storage, and be relatively simple. The methods of assessment used in the selection process consisted of examination of the difference equation, evaluation of the properties of the coefficient matrix, Taylor series analysis, and performance on model problems. Five schemes from the literature and three schemes developed during the course of the study were evaluated. This effort resulted in the incorporation of a scheme in 3D-TEACH which is usuallly more accurate than the hybrid differencing method and never less accurate.

A Six Sigma Trial For Reduction of Error Rates in Pathology Laboratory.

PubMed

Tosuner, Zeynep; Gücin, Zühal; Kiran, Tuğçe; Büyükpinarbaşili, Nur; Turna, Seval; Taşkiran, Olcay; Arici, Dilek Sema

2016-01-01

A major target of quality assurance is the minimization of error rates in order to enhance patient safety. Six Sigma is a method targeting zero error (3.4 errors per million events) used in industry. The five main principles of Six Sigma are defining, measuring, analysis, improvement and control. Using this methodology, the causes of errors can be examined and process improvement strategies can be identified. The aim of our study was to evaluate the utility of Six Sigma methodology in error reduction in our pathology laboratory. The errors encountered between April 2014 and April 2015 were recorded by the pathology personnel. Error follow-up forms were examined by the quality control supervisor, administrative supervisor and the head of the department. Using Six Sigma methodology, the rate of errors was measured monthly and the distribution of errors at the preanalytic, analytic and postanalytical phases was analysed. Improvement strategies were reclaimed in the monthly intradepartmental meetings and the control of the units with high error rates was provided. Fifty-six (52.4%) of 107 recorded errors in total were at the pre-analytic phase. Forty-five errors (42%) were recorded as analytical and 6 errors (5.6%) as post-analytical. Two of the 45 errors were major irrevocable errors. The error rate was 6.8 per million in the first half of the year and 1.3 per million in the second half, decreasing by 79.77%. The Six Sigma trial in our pathology laboratory provided the reduction of the error rates mainly in the pre-analytic and analytic phases.

Implementing smart infusion pumps with dose-error reduction software: real-world experiences.

PubMed

Heron, Claire

2017-04-27

Intravenous (IV) drug administration, especially with 'smart pumps', is complex and susceptible to errors. Although errors can occur at any stage of the IV medication process, most errors occur during reconstitution and administration. Dose-error reduction software (DERS) loaded on to infusion pumps incorporates a drug library with predefined upper and lower drug dose limits and infusion rates, which can reduce IV infusion errors. Although this is an important advance for patient safety at the point of care, uptake is still relatively low. This article discuses the challenges and benefits of implementing DERS in clinical practice as experienced by three UK trusts.

Improving patient safety through quality assurance.

PubMed

Raab, Stephen S

2006-05-01

Anatomic pathology laboratories use several quality assurance tools to detect errors and to improve patient safety. To review some of the anatomic pathology laboratory patient safety quality assurance practices. Different standards and measures in anatomic pathology quality assurance and patient safety were reviewed. Frequency of anatomic pathology laboratory error, variability in the use of specific quality assurance practices, and use of data for error reduction initiatives. Anatomic pathology error frequencies vary according to the detection method used. Based on secondary review, a College of American Pathologists Q-Probes study showed that the mean laboratory error frequency was 6.7%. A College of American Pathologists Q-Tracks study measuring frozen section discrepancy found that laboratories improved the longer they monitored and shared data. There is a lack of standardization across laboratories even for governmentally mandated quality assurance practices, such as cytologic-histologic correlation. The National Institutes of Health funded a consortium of laboratories to benchmark laboratory error frequencies, perform root cause analysis, and design error reduction initiatives, using quality assurance data. Based on the cytologic-histologic correlation process, these laboratories found an aggregate nongynecologic error frequency of 10.8%. Based on gynecologic error data, the laboratory at my institution used Toyota production system processes to lower gynecologic error frequencies and to improve Papanicolaou test metrics. Laboratory quality assurance practices have been used to track error rates, and laboratories are starting to use these data for error reduction initiatives.

Mathematical analysis study for radar data processing and enhancement. Part 1: Radar data analysis

NASA Technical Reports Server (NTRS)

James, R.; Brownlow, J. D.

1985-01-01

A study is performed under NASA contract to evaluate data from an AN/FPS-16 radar installed for support of flight programs at Dryden Flight Research Facility of NASA Ames Research Center. The purpose of this study is to provide information necessary for improving post-flight data reduction and knowledge of accuracy of derived radar quantities. Tracking data from six flights are analyzed. Noise and bias errors in raw tracking data are determined for each of the flights. A discussion of an altiude bias error during all of the tracking missions is included. This bias error is defined by utilizing pressure altitude measurements made during survey flights. Four separate filtering methods, representative of the most widely used optimal estimation techniques for enhancement of radar tracking data, are analyzed for suitability in processing both real-time and post-mission data. Additional information regarding the radar and its measurements, including typical noise and bias errors in the range and angle measurements, is also presented. This is in two parts. This is part 1, an analysis of radar data.

An error bound for a discrete reduced order model of a linear multivariable system

NASA Technical Reports Server (NTRS)

Al-Saggaf, Ubaid M.; Franklin, Gene F.

1987-01-01

The design of feasible controllers for high dimension multivariable systems can be greatly aided by a method of model reduction. In order for the design based on the order reduction to include a guarantee of stability, it is sufficient to have a bound on the model error. Previous work has provided such a bound for continuous-time systems for algorithms based on balancing. In this note an L-infinity bound is derived for model error for a method of order reduction of discrete linear multivariable systems based on balancing.

Prevention of hospital payment errors and implications for case management: a study of nine hospitals with a high proportion of short-term admissions over time.

PubMed

Hightower, Rebecca E

2008-01-01

Since the publication of the first analysis of Medicare payment error rates in 1998, the Office of Inspector General and the Centers for Medicare & Medicaid Services have focused resources on Medicare payment error prevention programs, now referred to as the Hospital Payment Monitoring Program. The purpose of the Hospital Payment Monitoring Program is to educate providers of Medicare Part A services in strategies to improve medical record documentation and decrease the potential for payment errors through appropriate claims completion. Although the payment error rates by state (and dollars paid in error) have decreased significantly, opportunities for improvement remain as demonstrated in this study of nine hospitals with a high proportion of short-term admissions over time. Previous studies by the Quality Improvement Organization had focused on inpatient stays of 1 day or less, a primary target due to the large amount of Medicare dollars spent on these admissions. Random review of Louisiana Medicare admissions revealed persistent medical record documentation and process issues regardless of length of stay as well as the opportunity for significant future savings to the Medicare Trust Fund. The purpose of this study was to determine whether opportunities for improvement in reduction of payment error continue to exist for inpatient admissions of greater than 1 day, despite focused education provided by Louisiana Health Care Review, the Louisiana Medicare Quality Improvement Organization, from 1999 to 2005, and to work individually with the nine selected hospitals to assist them in reducing the number of unnecessary short-term admissions and billing errors in each hospital by a minimum of 50% by the end of the study period. Inpatient Short-Term Acute Care Hospitals. A sample of claims for short-term stays (defined as an inpatient admission with a length of stay of 3 days or less excluding deaths, interim bills for those still a patient and those who left against medical advice) occurring during the baseline and remeasurement time frames was examined. The baseline period consisted of 1 month's claims-the complete month just prior to the start of approved project activities. Remeasurement was performed by each hospital and reported to the Quality Improvement Organization on a monthly basis following implementation of the hospital's quality improvement plan. Each hospital was required to provide a monthly remeasurement report by indicator until it had met its stated goal(s) for improvement for 2 consecutive months; therefore, each hospital completed its required monthly reporting for a specific indicator in a different month. Results were calculated for the following indicators: INDICATOR 1: Proportion of unnecessary short-term admissions = number of unnecessary short-term inpatient admissions/total short-term inpatient admissions in time frame. INDICATOR 2: Proportion of errors in billed treatment setting, that is, outpatient observation billed as inpatient = number of errors in billed treatment setting/total short-term admissions in time frame.Six of the 9 hospitals were able to accomplish reduction of their error rates within 6 months from the beginning of the study. The seventh hospital reached its goals in the 7th month, with the 2 remaining hospitals making progress toward their goals by the conclusion of the study. 1 Case managers must be up-to-date with payor requirements regarding medical record documentation for medical necessity of services and timing of inpatient admission, e.g., for Medicare, the date and time of the written physician's order for admission to the inpatient care setting is the date and time of inpatient admission. 2 The balancing of clinical decisions and financial considerations required of case managers in hospital settings remains an ongoing challenge. 3 Senior leadership must be engaged in ensuring the success of the case management program by providing the resources required. 4 Managers of case management programs must have in place an effective process to address compliance with changes in federal and state regulations and maintain collaborative relationships with senior leaders responsible for clinical, financial, and strategic plans and goals for the organization. 5 The case management process must include all related services, e.g., admissions, nursing services, health information management, finance/business services, contracting, medical staff, etc.

Impact of Stewardship Interventions on Antiretroviral Medication Errors in an Urban Medical Center: A 3-Year, Multiphase Study.

PubMed

Zucker, Jason; Mittal, Jaimie; Jen, Shin-Pung; Cheng, Lucy; Cennimo, David

2016-03-01

There is a high prevalence of HIV infection in Newark, New Jersey, with University Hospital admitting approximately 600 HIV-infected patients per year. Medication errors involving antiretroviral therapy (ART) could significantly affect treatment outcomes. The goal of this study was to evaluate the effectiveness of various stewardship interventions in reducing the prevalence of prescribing errors involving ART. This was a retrospective review of all inpatients receiving ART for HIV treatment during three distinct 6-month intervals over a 3-year period. During the first year, the baseline prevalence of medication errors was determined. During the second year, physician and pharmacist education was provided, and a computerized order entry system with drug information resources and prescribing recommendations was implemented. Prospective audit of ART orders with feedback was conducted in the third year. Analyses and comparisons were made across the three phases of this study. Of the 334 patients with HIV admitted in the first year, 45% had at least one antiretroviral medication error and 38% had uncorrected errors at the time of discharge. After education and computerized order entry, significant reductions in medication error rates were observed compared to baseline rates; 36% of 315 admissions had at least one error and 31% had uncorrected errors at discharge. While the prevalence of antiretroviral errors in year 3 was similar to that of year 2 (37% of 276 admissions), there was a significant decrease in the prevalence of uncorrected errors at discharge (12%) with the use of prospective review and intervention. Interventions, such as education and guideline development, can aid in reducing ART medication errors, but a committed stewardship program is necessary to elicit the greatest impact. © 2016 Pharmacotherapy Publications, Inc.

Error detection and reduction in blood banking.

PubMed

Motschman, T L; Moore, S B

1996-12-01

Error management plays a major role in facility process improvement efforts. By detecting and reducing errors, quality and, therefore, patient care improve. It begins with a strong organizational foundation of management attitude with clear, consistent employee direction and appropriate physical facilities. Clearly defined critical processes, critical activities, and SOPs act as the framework for operations as well as active quality monitoring. To assure that personnel can detect an report errors they must be trained in both operational duties and error management practices. Use of simulated/intentional errors and incorporation of error detection into competency assessment keeps employees practiced, confident, and diminishes fear of the unknown. Personnel can clearly see that errors are indeed used as opportunities for process improvement and not for punishment. The facility must have a clearly defined and consistently used definition for reportable errors. Reportable errors should include those errors with potentially harmful outcomes as well as those errors that are "upstream," and thus further away from the outcome. A well-written error report consists of who, what, when, where, why/how, and follow-up to the error. Before correction can occur, an investigation to determine the underlying cause of the error should be undertaken. Obviously, the best corrective action is prevention. Correction can occur at five different levels; however, only three of these levels are directed at prevention. Prevention requires a method to collect and analyze data concerning errors. In the authors' facility a functional error classification method and a quality system-based classification have been useful. An active method to search for problems uncovers them further upstream, before they can have disastrous outcomes. In the continual quest for improving processes, an error management program is itself a process that needs improvement, and we must strive to always close the circle of quality assurance. Ultimately, the goal of better patient care will be the reward.

Derivation of an analytic expression for the error associated with the noise reduction rating

NASA Astrophysics Data System (ADS)

Murphy, William J.

2005-04-01

Hearing protection devices are assessed using the Real Ear Attenuation at Threshold (REAT) measurement procedure for the purpose of estimating the amount of noise reduction provided when worn by a subject. The rating number provided on the protector label is a function of the mean and standard deviation of the REAT results achieved by the test subjects. If a group of subjects have a large variance, then it follows that the certainty of the rating should be correspondingly lower. No estimate of the error of a protector's rating is given by existing standards or regulations. Propagation of errors was applied to the Noise Reduction Rating to develop an analytic expression for the hearing protector rating error term. Comparison of the analytic expression for the error to the standard deviation estimated from Monte Carlo simulation of subject attenuations yielded a linear relationship across several protector types and assumptions for the variance of the attenuations.

Error reduction in EMG signal decomposition

PubMed Central

Kline, Joshua C.

2014-01-01

Decomposition of the electromyographic (EMG) signal into constituent action potentials and the identification of individual firing instances of each motor unit in the presence of ambient noise are inherently probabilistic processes, whether performed manually or with automated algorithms. Consequently, they are subject to errors. We set out to classify and reduce these errors by analyzing 1,061 motor-unit action-potential trains (MUAPTs), obtained by decomposing surface EMG (sEMG) signals recorded during human voluntary contractions. Decomposition errors were classified into two general categories: location errors representing variability in the temporal localization of each motor-unit firing instance and identification errors consisting of falsely detected or missed firing instances. To mitigate these errors, we developed an error-reduction algorithm that combines multiple decomposition estimates to determine a more probable estimate of motor-unit firing instances with fewer errors. The performance of the algorithm is governed by a trade-off between the yield of MUAPTs obtained above a given accuracy level and the time required to perform the decomposition. When applied to a set of sEMG signals synthesized from real MUAPTs, the identification error was reduced by an average of 1.78%, improving the accuracy to 97.0%, and the location error was reduced by an average of 1.66 ms. The error-reduction algorithm in this study is not limited to any specific decomposition strategy. Rather, we propose it be used for other decomposition methods, especially when analyzing precise motor-unit firing instances, as occurs when measuring synchronization. PMID:25210159

Generation and Computerized Simulation of Meshing and Contact of Modified Involute Helical Gears

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Chen, Ningxin; Lu, Jian

1995-01-01

The design and generation of modified involute helical gears that have a localized and stable bearing contact, and reduced noise and vibration characteristics are described. The localization of the bearing contact is achieved by the mismatch of the two generating surfaces that are used for generation of the pinion and the gear. The reduction of noise and vibration will be achieved by application of a parabolic function of transmission errors that is able to absorb the almost linear function of transmission errors caused by gear misalignment. The meshing and contact of misaligned gear drives can be analyzed by application of computer programs that have been developed. The computations confirmed the effectiveness of the proposed modification of the gear geometry. A numerical example that illustrates the developed theory is provided.

Deep space target location with Hubble Space Telescope (HST) and Hipparcos data

NASA Technical Reports Server (NTRS)

Null, George W.

1988-01-01

Interplanetary spacecraft navigation requires accurate a priori knowledge of target positions. A concept is presented for attaining improved target ephemeris accuracy using two future Earth-orbiting optical observatories, the European Space Agency (ESA) Hipparcos observatory and the Nasa Hubble Space Telescope (HST). Assuming nominal observatory performance, the Hipparcos data reduction will provide an accurate global star catalog, and HST will provide a capability for accurate angular measurements of stars and solar system bodies. The target location concept employs HST to observe solar system bodies relative to Hipparcos catalog stars and to determine the orientation (frame tie) of these stars to compact extragalactic radio sources. The target location process is described, the major error sources discussed, the potential target ephemeris error predicted, and mission applications identified. Preliminary results indicate that ephemeris accuracy comparable to the errors in individual Hipparcos catalog stars may be possible with a more extensive HST observing program. Possible future ground and spacebased replacements for Hipparcos and HST astrometric capabilities are also discussed.

On the connection between multigrid and cyclic reduction

NASA Technical Reports Server (NTRS)

Merriam, M. L.

1984-01-01

A technique is shown whereby it is possible to relate a particular multigrid process to cyclic reduction using purely mathematical arguments. This technique suggest methods for solving Poisson's equation in 1-, 2-, or 3-dimensions with Dirichlet or Neumann boundary conditions. In one dimension the method is exact and, in fact, reduces to cyclic reduction. This provides a valuable reference point for understanding multigrid techniques. The particular multigrid process analyzed is referred to here as Approximate Cyclic Reduction (ACR) and is one of a class known as Multigrid Reduction methods in the literature. It involves one approximation with a known error term. It is possible to relate the error term in this approximation with certain eigenvector components of the error. These are sharply reduced in amplitude by classical relaxation techniques. The approximation can thus be made a very good one.

The evolution of the FIGARO data reduction system

NASA Technical Reports Server (NTRS)

Shortridge, K.

1992-01-01

The Figaro data reduction system originated at Caltech around 1983. It was based on concepts being developed in the U.K. by the Starlink organization, particularly the use of hierarchical self-defining data structures and the abstraction of most user-interaction into a set of 'parameter system' routines. Since 1984 it has continued to be developed at AAO, in collaboration with Starlink and Caltech. It was adopted as Starlink's main spectroscopic data reduction package, although it is by no means limited to spectra; it has operations for images and data cubes and even a few (very specialized) for four-dimensional data hypercubes. It continued to be used at Caltech and will be used at the Keck. It is also in use at a variety of other organizations around the world. Figaro was originally a system for VMS Vaxes. Recently it was ported (at Caltech) to run on SUN's, and work is underway at the University of New South Wales on a DecStation version. It is hoped to coordinate all this work into a unified release, but coordination of the development of a system by organizations covering three continents poses a number of interesting administrative problems. The hierarchical data structures used by Figaro allow it to handle a variety of types of data, and to add new items to data structures. Error and data quality information was added to the basic file format used, error information being particularly useful for infrared data. Cooperating sets of programs can add specific sub-structures to data files to carry information that they understand (polarimetry data containing multiple data arrays, for example), without this affecting the way other programs handle the files. Complex instrument-specific ancillary information can be added to data files written at a telescope and can be used by programs that understand the instrumental details in order to produce properly calibrated data files. Once this preliminary data processing was done the resulting files contain 'ordinary' spectra or images that can be processed by programs that are not instrument-specific. The structures holding the instrumental information can then be discarded from the files. Much effort has gone into trying to make it easy to write Figaro programs; data access subroutines are now available to handle access to all the conventional items found in Figaro files (main data arrays, error information, quality information etc), and programs that only need to access such items can be very simple indeed. A large number of Figaro users do indeed write their own Figaro applications using these routines. The fact that Figaro programs are written as callable subroutines getting information from the user through a small set of parameter routines means that they can be invoked in numerous ways; they are normally linked and run as individual programs (called by a small main routine that is generated automatically), but are also available linked to run under the ADAM data acquisition system and there is an interface that lets them be called as part of a user-written Fortran program. The long-term future of Figaro probably depends to a large extent on how successfully it manages the transition from being a VMS-only system to being a multi-platform system.

Evaluation of analytical errors in a clinical chemistry laboratory: a 3 year experience.

PubMed

Sakyi, As; Laing, Ef; Ephraim, Rk; Asibey, Of; Sadique, Ok

2015-01-01

Proficient laboratory service is the cornerstone of modern healthcare systems and has an impact on over 70% of medical decisions on admission, discharge, and medications. In recent years, there is an increasing awareness of the importance of errors in laboratory practice and their possible negative impact on patient outcomes. We retrospectively analyzed data spanning a period of 3 years on analytical errors observed in our laboratory. The data covered errors over the whole testing cycle including pre-, intra-, and post-analytical phases and discussed strategies pertinent to our settings to minimize their occurrence. We described the occurrence of pre-analytical, analytical and post-analytical errors observed at the Komfo Anokye Teaching Hospital clinical biochemistry laboratory during a 3-year period from January, 2010 to December, 2012. Data were analyzed with Graph Pad Prism 5(GraphPad Software Inc. CA USA). A total of 589,510 tests was performed on 188,503 outpatients and hospitalized patients. The overall error rate for the 3 years was 4.7% (27,520/58,950). Pre-analytical, analytical and post-analytical errors contributed 3.7% (2210/58,950), 0.1% (108/58,950), and 0.9% (512/58,950), respectively. The number of tests reduced significantly over the 3-year period, but this did not correspond with a reduction in the overall error rate (P = 0.90) along with the years. Analytical errors are embedded within our total process setup especially pre-analytical and post-analytical phases. Strategic measures including quality assessment programs for staff involved in pre-analytical processes should be intensified.

Human Papillomavirus (HPV) Genotyping: Automation and Application in Routine Laboratory Testing

PubMed Central

Torres, M; Fraile, L; Echevarria, JM; Hernandez Novoa, B; Ortiz, M

2012-01-01

A large number of assays designed for genotyping human papillomaviruses (HPV) have been developed in the last years. They perform within a wide range of analytical sensitivity and specificity values for the different viral types, and are used either for diagnosis, epidemiological studies, evaluation of vaccines and implementing and monitoring of vaccination programs. Methods for specific genotyping of HPV-16 and HPV-18 are also useful for the prevention of cervical cancer in screening programs. Some commercial tests are, in addition, fully or partially automated. Automation of HPV genotyping presents advantages such as the simplicity of the testing procedure for the operator, the ability to process a large number of samples in a short time, and the reduction of human errors from manual operations, allowing a better quality assurance and a reduction of cost. The present review collects information about the current HPV genotyping tests, with special attention to practical aspects influencing their use in clinical laboratories. PMID:23248734

The application of SHERPA (Systematic Human Error Reduction and Prediction Approach) in the development of compensatory cognitive rehabilitation strategies for stroke patients with left and right brain damage.

PubMed

Hughes, Charmayne M L; Baber, Chris; Bienkiewicz, Marta; Worthington, Andrew; Hazell, Alexa; Hermsdörfer, Joachim

2015-01-01

Approximately 33% of stroke patients have difficulty performing activities of daily living, often committing errors during the planning and execution of such activities. The objective of this study was to evaluate the ability of the human error identification (HEI) technique SHERPA (Systematic Human Error Reduction and Prediction Approach) to predict errors during the performance of daily activities in stroke patients with left and right hemisphere lesions. Using SHERPA we successfully predicted 36 of the 38 observed errors, with analysis indicating that the proportion of predicted and observed errors was similar for all sub-tasks and severity levels. HEI results were used to develop compensatory cognitive strategies that clinicians could employ to reduce or prevent errors from occurring. This study provides evidence for the reliability and validity of SHERPA in the design of cognitive rehabilitation strategies in stroke populations.

Medical Error Avoidance in Intraoperative Neurophysiological Monitoring: The Communication Imperative.

PubMed

Skinner, Stan; Holdefer, Robert; McAuliffe, John J; Sala, Francesco

2017-11-01

Error avoidance in medicine follows similar rules that apply within the design and operation of other complex systems. The error-reduction concepts that best fit the conduct of testing during intraoperative neuromonitoring are forgiving design (reversibility of signal loss to avoid/prevent injury) and system redundancy (reduction of false reports by the multiplication of the error rate of tests independently assessing the same structure). However, error reduction in intraoperative neuromonitoring is complicated by the dichotomous roles (and biases) of the neurophysiologist (test recording and interpretation) and surgeon (intervention). This "interventional cascade" can be given as follows: test → interpretation → communication → intervention → outcome. Observational and controlled trials within operating rooms demonstrate that optimized communication, collaboration, and situational awareness result in fewer errors. Well-functioning operating room collaboration depends on familiarity and trust among colleagues. Checklists represent one method to initially enhance communication and avoid obvious errors. All intraoperative neuromonitoring supervisors should strive to use sufficient means to secure situational awareness and trusted communication/collaboration. Face-to-face audiovisual teleconnections may help repair deficiencies when a particular practice model disallows personal operating room availability. All supervising intraoperative neurophysiologists need to reject an insular or deferential or distant mindset.

ISO Key Project: Exploring the Full Range of Quasar/Agn Properties

NASA Technical Reports Server (NTRS)

Wilkes, Belinda; Oliversen, Ronald J. (Technical Monitor)

2003-01-01

While most of the work on this program has been completed, as previously reported, the portion of the program dealing with the subtopic of ISO LWS data analysis and reduction for the LWS Extragalactic Science Team and its leader, Dr. Howard Smith, is still active. This program in fact continues to generate results, and newly available computer modeling has extended the value of the datasets. As a result the team requests a one-year no-cost extension to this program, through 31 December 2004. The essence of the proposal is to perform ISO spectroscopic studies, including data analysis and modeling, of star-formation regions using an ensemble of archival space-based data from the Infrared Space Observatory's Long Wavelength Spectrometer and Short Wavelength Spectrometer, but including as well some other spectroscopic databases. Four kinds of regions are considered in the studies: (1) disks around more evolved objects; (2) young, low or high mass pre-main sequence stars in star-formation regions; (3) star formation in external, bright IR galaxies; and (4) the galactic center. One prime focus of the program is the OH lines in the far infrared. The program has the following goals: 1) Refine the data analysis of ISO observations to obtain deeper and better SNR results on selected sources. The ISO data itself underwent 'pipeline 10' reductions in early 2001, and additional 'hands-on data reduction packages' were supplied by the ISO teams in 2001. The Fabry-Perot database is particularly sensitive to noise and slight calibration errors; 2) Model the atomic and molecular line shapes, in particular the OH lines, using revised Monte-Carlo techniques developed by the SWAS team at the Center for Astrophysics; 3) Attend scientific meetings and workshops; 4) Perform E&PO activities related to infrared astrophysics and/or spectroscopy.

Discretization vs. Rounding Error in Euler's Method

ERIC Educational Resources Information Center

Borges, Carlos F.

2011-01-01

Euler's method for solving initial value problems is an excellent vehicle for observing the relationship between discretization error and rounding error in numerical computation. Reductions in stepsize, in order to decrease discretization error, necessarily increase the number of steps and so introduce additional rounding error. The problem is…

The Error in Total Error Reduction

PubMed Central

Witnauer, James E.; Urcelay, Gonzalo P.; Miller, Ralph R.

2013-01-01

Most models of human and animal learning assume that learning is proportional to the discrepancy between a delivered outcome and the outcome predicted by all cues present during that trial (i.e., total error across a stimulus compound). This total error reduction (TER) view has been implemented in connectionist and artificial neural network models to describe the conditions under which weights between units change. Electrophysiological work has revealed that the activity of dopamine neurons is correlated with the total error signal in models of reward learning. Similar neural mechanisms presumably support fear conditioning, human contingency learning, and other types of learning. Using a computational modelling approach, we compared several TER models of associative learning to an alternative model that rejects the TER assumption in favor of local error reduction (LER), which assumes that learning about each cue is proportional to the discrepancy between the delivered outcome and the outcome predicted by that specific cue on that trial. The LER model provided a better fit to the reviewed data than the TER models. Given the superiority of the LER model with the present data sets, acceptance of TER should be tempered. PMID:23891930

Reduction in Chemotherapy Mixing Errors Using Six Sigma: Illinois CancerCare Experience.

PubMed

Heard, Bridgette; Miller, Laura; Kumar, Pankaj

2012-03-01

Chemotherapy mixing errors (CTMRs), although rare, have serious consequences. Illinois CancerCare is a large practice with multiple satellite offices. The goal of this study was to reduce the number of CTMRs using Six Sigma methods. A Six Sigma team consisting of five participants (registered nurses and pharmacy technicians [PTs]) was formed. The team had 10 hours of Six Sigma training in the DMAIC (ie, Define, Measure, Analyze, Improve, Control) process. Measurement of errors started from the time the CT order was verified by the PT to the time of CT administration by the nurse. Data collection included retrospective error tracking software, system audits, and staff surveys. Root causes of CTMRs included inadequate knowledge of CT mixing protocol, inconsistencies in checking methods, and frequent changes in staffing of clinics. Initial CTMRs (n = 33,259) constituted 0.050%, with 77% of these errors affecting patients. The action plan included checklists, education, and competency testing. The postimplementation error rate (n = 33,376, annualized) over a 3-month period was reduced to 0.019%, with only 15% of errors affecting patients. Initial Sigma was calculated at 4.2; this process resulted in the improvement of Sigma to 5.2, representing a 100-fold reduction. Financial analysis demonstrated a reduction in annualized loss of revenue (administration charges and drug wastage) from $11,537.95 (Medicare Average Sales Price) before the start of the project to $1,262.40. The Six Sigma process is a powerful technique in the reduction of CTMRs.

Boundary Control of Linear Uncertain 1-D Parabolic PDE Using Approximate Dynamic Programming.

PubMed

Talaei, Behzad; Jagannathan, Sarangapani; Singler, John

2018-04-01

This paper develops a near optimal boundary control method for distributed parameter systems governed by uncertain linear 1-D parabolic partial differential equations (PDE) by using approximate dynamic programming. A quadratic surface integral is proposed to express the optimal cost functional for the infinite-dimensional state space. Accordingly, the Hamilton-Jacobi-Bellman (HJB) equation is formulated in the infinite-dimensional domain without using any model reduction. Subsequently, a neural network identifier is developed to estimate the unknown spatially varying coefficient in PDE dynamics. Novel tuning law is proposed to guarantee the boundedness of identifier approximation error in the PDE domain. A radial basis network (RBN) is subsequently proposed to generate an approximate solution for the optimal surface kernel function online. The tuning law for near optimal RBN weights is created, such that the HJB equation error is minimized while the dynamics are identified and closed-loop system remains stable. Ultimate boundedness (UB) of the closed-loop system is verified by using the Lyapunov theory. The performance of the proposed controller is successfully confirmed by simulation on an unstable diffusion-reaction process.

Pilot error in air carrier mishaps: longitudinal trends among 558 reports, 1983-2002.

PubMed

Baker, Susan P; Qiang, Yandong; Rebok, George W; Li, Guohua

2008-01-01

Many interventions have been implemented in recent decades to reduce pilot error in flight operations. This study aims to identify longitudinal trends in the prevalence and patterns of pilot error and other factors in U.S. air carrier mishaps. National Transportation Safety Board investigation reports were examined for 558 air carrier mishaps during 1983-2002. Pilot errors and circumstances of mishaps were described and categorized. Rates were calculated per 10 million flights. The overall mishap rate remained fairly stable, but the proportion of mishaps involving pilot error decreased from 42% in 1983-87 to 25% in 1998-2002, a 40% reduction. The rate of mishaps related to poor decisions declined from 6.2 to 1.8 per 10 million flights, a 71% reduction; much of this decrease was due to a 76% reduction in poor decisions related to weather. Mishandling wind or runway conditions declined by 78%. The rate of mishaps involving poor crew interaction declined by 68%. Mishaps during takeoff declined by 70%, from 5.3 to 1.6 per 10 million flights. The latter reduction was offset by an increase in mishaps while the aircraft was standing, from 2.5 to 6.0 per 10 million flights, and during pushback, which increased from 0 to 3.1 per 10 million flights. Reductions in pilot errors involving decision making and crew coordination are important trends that may reflect improvements in training and technological advances that facilitate good decisions. Mishaps while aircraft are standing and during pushback have increased and deserve special attention.

Pilot Error in Air Carrier Mishaps: Longitudinal Trends Among 558 Reports, 1983–2002

PubMed Central

Baker, Susan P.; Qiang, Yandong; Rebok, George W.; Li, Guohua

2009-01-01

Background Many interventions have been implemented in recent decades to reduce pilot error in flight operations. This study aims to identify longitudinal trends in the prevalence and patterns of pilot error and other factors in U.S. air carrier mishaps. Method National Transportation Safety Board investigation reports were examined for 558 air carrier mishaps during 1983–2002. Pilot errors and circumstances of mishaps were described and categorized. Rates were calculated per 10 million flights. Results The overall mishap rate remained fairly stable, but the proportion of mishaps involving pilot error decreased from 42% in 1983–87 to 25% in 1998–2002, a 40% reduction. The rate of mishaps related to poor decisions declined from 6.2 to 1.8 per 10 million flights, a 71% reduction; much of this decrease was due to a 76% reduction in poor decisions related to weather. Mishandling wind or runway conditions declined by 78%. The rate of mishaps involving poor crew interaction declined by 68%. Mishaps during takeoff declined by 70%, from 5.3 to 1.6 per 10 million flights. The latter reduction was offset by an increase in mishaps while the aircraft was standing, from 2.5 to 6.0 per 10 million flights, and during pushback, which increased from 0 to 3.1 per 10 million flights. Conclusions Reductions in pilot errors involving decision making and crew coordination are important trends that may reflect improvements in training and technological advances that facilitate good decisions. Mishaps while aircraft are standing and during push-back have increased and deserve special attention. PMID:18225771

The Effect of Auditory Information on Patterns of Intrusions and Reductions

ERIC Educational Resources Information Center

Slis, Anneke; van Lieshout, Pascal

2016-01-01

Purpose: The study investigates whether auditory information affects the nature of intrusion and reduction errors in reiterated speech. These errors are hypothesized to arise as a consequence of autonomous mechanisms to stabilize movement coordination. The specific question addressed is whether this process is affected by auditory information so…

Documentation of study medication dispensing in a prospective large randomized clinical trial: experiences from the ARISTOTLE Trial.

PubMed

Alexander, John H; Levy, Elliott; Lawrence, Jack; Hanna, Michael; Waclawski, Anthony P; Wang, Junyuan; Califf, Robert M; Wallentin, Lars; Granger, Christopher B

2013-09-01

In ARISTOTLE, apixaban resulted in a 21% reduction in stroke, a 31% reduction in major bleeding, and an 11% reduction in death. However, approval of apixaban was delayed to investigate a statement in the clinical study report that "7.3% of subjects in the apixaban group and 1.2% of subjects in the warfarin group received, at some point during the study, a container of the wrong type." Rates of study medication dispensing error were characterized through reviews of study medication container tear-off labels in 6,520 participants from randomly selected study sites. The potential effect of dispensing errors on study outcomes was statistically simulated in sensitivity analyses in the overall population. The rate of medication dispensing error resulting in treatment error was 0.04%. Rates of participants receiving at least 1 incorrect container were 1.04% (34/3,273) in the apixaban group and 0.77% (25/3,247) in the warfarin group. Most of the originally reported errors were data entry errors in which the correct medication container was dispensed but the wrong container number was entered into the case report form. Sensitivity simulations in the overall trial population showed no meaningful effect of medication dispensing error on the main efficacy and safety outcomes. Rates of medication dispensing error were low and balanced between treatment groups. The initially reported dispensing error rate was the result of data recording and data management errors and not true medication dispensing errors. These analyses confirm the previously reported results of ARISTOTLE. © 2013.

Final Report: Correctness Tools for Petascale Computing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mellor-Crummey, John

2014-10-27

In the course of developing parallel programs for leadership computing systems, subtle programming errors often arise that are extremely difficult to diagnose without tools. To meet this challenge, University of Maryland, the University of Wisconsin—Madison, and Rice University worked to develop lightweight tools to help code developers pinpoint a variety of program correctness errors that plague parallel scientific codes. The aim of this project was to develop software tools that help diagnose program errors including memory leaks, memory access errors, round-off errors, and data races. Research at Rice University focused on developing algorithms and data structures to support efficient monitoringmore » of multithreaded programs for memory access errors and data races. This is a final report about research and development work at Rice University as part of this project.« less

Research on slow electron collision processes in gases. Final report, September 15, 1970--December 31, 1972

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baldwin, G C

1974-04-30

Research on low energy electron collisions in gases by the time-of- flight velocity selection technique included, as a preliminary to total cross section measurements, investigations of the statistical and systematic errors inherent in the technique. In particular, thermal transpiration and instrumental fluctuation errors in manometry were investigated, and the results embodied in computer programs for data reduction. The instrumental system was improved to permit extended periods of data accumulation without manual attention. Total cross section measurements in helium, made prior to, and in molecular nitrogen, made after the supporting work was completed, are reported. The total cross sec tion ofmore » helium is found to be higher than reported in previous beam determinations. That of nitrogen is found to be structureless at low energies. (auth)« less

Effective Compiler Error Message Enhancement for Novice Programming Students

ERIC Educational Resources Information Center

Becker, Brett A.; Glanville, Graham; Iwashima, Ricardo; McDonnell, Claire; Goslin, Kyle; Mooney, Catherine

2016-01-01

Programming is an essential skill that many computing students are expected to master. However, programming can be difficult to learn. Successfully interpreting compiler error messages (CEMs) is crucial for correcting errors and progressing toward success in programming. Yet these messages are often difficult to understand and pose a barrier to…

Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS)

NASA Technical Reports Server (NTRS)

Alexander, Tiffaney Miller

2017-01-01

Research results have shown that more than half of aviation, aerospace and aeronautics mishaps incidents are attributed to human error. As a part of Safety within space exploration ground processing operations, the identification and/or classification of underlying contributors and causes of human error must be identified, in order to manage human error. This research provides a framework and methodology using the Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS), as an analysis tool to identify contributing factors, their impact on human error events, and predict the Human Error probabilities (HEPs) of future occurrences. This research methodology was applied (retrospectively) to six (6) NASA ground processing operations scenarios and thirty (30) years of Launch Vehicle related mishap data. This modifiable framework can be used and followed by other space and similar complex operations.

Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS)

NASA Technical Reports Server (NTRS)

Alexander, Tiffaney Miller

2017-01-01

Research results have shown that more than half of aviation, aerospace and aeronautics mishaps/incidents are attributed to human error. As a part of Safety within space exploration ground processing operations, the identification and/or classification of underlying contributors and causes of human error must be identified, in order to manage human error. This research provides a framework and methodology using the Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS), as an analysis tool to identify contributing factors, their impact on human error events, and predict the Human Error probabilities (HEPs) of future occurrences. This research methodology was applied (retrospectively) to six (6) NASA ground processing operations scenarios and thirty (30) years of Launch Vehicle related mishap data. This modifiable framework can be used and followed by other space and similar complex operations.

Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS)

NASA Technical Reports Server (NTRS)

Alexander, Tiffaney Miller

2017-01-01

Research results have shown that more than half of aviation, aerospace and aeronautics mishaps incidents are attributed to human error. As a part of Quality within space exploration ground processing operations, the identification and or classification of underlying contributors and causes of human error must be identified, in order to manage human error.This presentation will provide a framework and methodology using the Human Error Assessment and Reduction Technique (HEART) and Human Factor Analysis and Classification System (HFACS), as an analysis tool to identify contributing factors, their impact on human error events, and predict the Human Error probabilities (HEPs) of future occurrences. This research methodology was applied (retrospectively) to six (6) NASA ground processing operations scenarios and thirty (30) years of Launch Vehicle related mishap data. This modifiable framework can be used and followed by other space and similar complex operations.

Using Healthcare Failure Mode and Effect Analysis to reduce medication errors in the process of drug prescription, validation and dispensing in hospitalised patients.

PubMed

Vélez-Díaz-Pallarés, Manuel; Delgado-Silveira, Eva; Carretero-Accame, María Emilia; Bermejo-Vicedo, Teresa

2013-01-01

To identify actions to reduce medication errors in the process of drug prescription, validation and dispensing, and to evaluate the impact of their implementation. A Health Care Failure Mode and Effect Analysis (HFMEA) was supported by a before-and-after medication error study to measure the actual impact on error rate after the implementation of corrective actions in the process of drug prescription, validation and dispensing in wards equipped with computerised physician order entry (CPOE) and unit-dose distribution system (788 beds out of 1080) in a Spanish university hospital. The error study was carried out by two observers who reviewed medication orders on a daily basis to register prescription errors by physicians and validation errors by pharmacists. Drugs dispensed in the unit-dose trolleys were reviewed for dispensing errors. Error rates were expressed as the number of errors for each process divided by the total opportunities for error in that process times 100. A reduction in prescription errors was achieved by providing training for prescribers on CPOE, updating prescription procedures, improving clinical decision support and automating the software connection to the hospital census (relative risk reduction (RRR), 22.0%; 95% CI 12.1% to 31.8%). Validation errors were reduced after optimising time spent in educating pharmacy residents on patient safety, developing standardised validation procedures and improving aspects of the software's database (RRR, 19.4%; 95% CI 2.3% to 36.5%). Two actions reduced dispensing errors: reorganising the process of filling trolleys and drawing up a protocol for drug pharmacy checking before delivery (RRR, 38.5%; 95% CI 14.1% to 62.9%). HFMEA facilitated the identification of actions aimed at reducing medication errors in a healthcare setting, as the implementation of several of these led to a reduction in errors in the process of drug prescription, validation and dispensing.

Two Topics in Seasonal Streamflow Forecasting: Soil Moisture Initialization Error and Precipitation Downscaling

NASA Technical Reports Server (NTRS)

Koster, Randal; Walker, Greg; Mahanama, Sarith; Reichle, Rolf

2012-01-01

Continental-scale offline simulations with a land surface model are used to address two important issues in the forecasting of large-scale seasonal streamflow: (i) the extent to which errors in soil moisture initialization degrade streamflow forecasts, and (ii) the extent to which the downscaling of seasonal precipitation forecasts, if it could be done accurately, would improve streamflow forecasts. The reduction in streamflow forecast skill (with forecasted streamflow measured against observations) associated with adding noise to a soil moisture field is found to be, to first order, proportional to the average reduction in the accuracy of the soil moisture field itself. This result has implications for streamflow forecast improvement under satellite-based soil moisture measurement programs. In the second and more idealized ("perfect model") analysis, precipitation downscaling is found to have an impact on large-scale streamflow forecasts only if two conditions are met: (i) evaporation variance is significant relative to the precipitation variance, and (ii) the subgrid spatial variance of precipitation is adequately large. In the large-scale continental region studied (the conterminous United States), these two conditions are met in only a somewhat limited area.

An overview of intravenous-related medication administration errors as reported to MEDMARX, a national medication error-reporting program.

PubMed

Hicks, Rodney W; Becker, Shawn C

2006-01-01

Medication errors can be harmful, especially if they involve the intravenous (IV) route of administration. A mixed-methodology study using a 5-year review of 73,769 IV-related medication errors from a national medication error reporting program indicates that between 3% and 5% of these errors were harmful. The leading type of error was omission, and the leading cause of error involved clinician performance deficit. Using content analysis, three themes-product shortage, calculation errors, and tubing interconnectivity-emerge and appear to predispose patients to harm. Nurses often participate in IV therapy, and these findings have implications for practice and patient safety. Voluntary medication error-reporting programs afford an opportunity to improve patient care and to further understanding about the nature of IV-related medication errors.

Moments of inclination error distribution computer program

NASA Technical Reports Server (NTRS)

Myler, T. R.

1981-01-01

A FORTRAN coded computer program is described which calculates orbital inclination error statistics using a closed-form solution. This solution uses a data base of trajectory errors from actual flights to predict the orbital inclination error statistics. The Scott flight history data base consists of orbit insertion errors in the trajectory parameters - altitude, velocity, flight path angle, flight azimuth, latitude and longitude. The methods used to generate the error statistics are of general interest since they have other applications. Program theory, user instructions, output definitions, subroutine descriptions and detailed FORTRAN coding information are included.

Telescope Scientist on the Advanced X-ray Astrophysics Observatory

NASA Technical Reports Server (NTRS)

Smith, Carl M. (Technical Monitor); VanSpeybroeck, Leon; Tananbaum, Harvey D.

2004-01-01

In this period, the Chandra X-ray Observatory continued to perform exceptionally well, with many scientific observations and spectacular results. The HRMA performance continues to be essentially identical to that predicted from ground calibration data. The Telescope Scientist Team has improved the mirror model to provide a more accurate description to the Chandra observers, enabling them to reduce the systematic errors and uncertainties in their data reduction. There also has been good progress in the scientific program. Using the Telescope Scientist GTO time, we carried out an extensive Chandra program to observe distant clusters of galaxies. The goals of this program were to use clusters to derive cosmological constraints and to investigate the physics and evolution of clusters. A total of 71 clusters were observed with ACIS-I; the last observations were completed in December 2003.

Technology Readiness of Early Career Nurse Trainees: Utilization of the Technology Readiness Index (TRI).

PubMed

Odlum, Michelle

2016-01-01

Health Information Technology (HIT) adoption by clinicians, including nurses, will lead to reduction in healthcare costs and clinical errors and improve health outcomes. Understanding the importance of technology adoption, the current study utilized the Technology Readiness Index to explore technology perceptions of nursing students. Our analysis identifies factors that may influence perceptions of technology, including decreased optimism for students with clinical experience and increased discomfort of US born students. Our study provides insight to inform training programs to further meet the increasing demands of skilled nursing staff.

Evaluation of Analytical Errors in a Clinical Chemistry Laboratory: A 3 Year Experience

PubMed Central

Sakyi, AS; Laing, EF; Ephraim, RK; Asibey, OF; Sadique, OK

2015-01-01

Background: Proficient laboratory service is the cornerstone of modern healthcare systems and has an impact on over 70% of medical decisions on admission, discharge, and medications. In recent years, there is an increasing awareness of the importance of errors in laboratory practice and their possible negative impact on patient outcomes. Aim: We retrospectively analyzed data spanning a period of 3 years on analytical errors observed in our laboratory. The data covered errors over the whole testing cycle including pre-, intra-, and post-analytical phases and discussed strategies pertinent to our settings to minimize their occurrence. Materials and Methods: We described the occurrence of pre-analytical, analytical and post-analytical errors observed at the Komfo Anokye Teaching Hospital clinical biochemistry laboratory during a 3-year period from January, 2010 to December, 2012. Data were analyzed with Graph Pad Prism 5(GraphPad Software Inc. CA USA). Results: A total of 589,510 tests was performed on 188,503 outpatients and hospitalized patients. The overall error rate for the 3 years was 4.7% (27,520/58,950). Pre-analytical, analytical and post-analytical errors contributed 3.7% (2210/58,950), 0.1% (108/58,950), and 0.9% (512/58,950), respectively. The number of tests reduced significantly over the 3-year period, but this did not correspond with a reduction in the overall error rate (P = 0.90) along with the years. Conclusion: Analytical errors are embedded within our total process setup especially pre-analytical and post-analytical phases. Strategic measures including quality assessment programs for staff involved in pre-analytical processes should be intensified. PMID:25745569

Microdensitometer errors: Their effect on photometric data reduction

NASA Technical Reports Server (NTRS)

Bozyan, E. P.; Opal, C. B.

1984-01-01

The performance of densitometers used for photometric data reduction of high dynamic range electrographic plate material is analyzed. Densitometer repeatability is tested by comparing two scans of one plate. Internal densitometer errors are examined by constructing histograms of digitized densities and finding inoperative bits and differential nonlinearity in the analog to digital converter. Such problems appear common to the four densitometers used in this investigation and introduce systematic algorithm dependent errors in the results. Strategies to improve densitometer performance are suggested.

Decreasing scoring errors on Wechsler Scale Vocabulary, Comprehension, and Similarities subtests: a preliminary study.

PubMed

Linger, Michele L; Ray, Glen E; Zachar, Peter; Underhill, Andrea T; LoBello, Steven G

2007-10-01

Studies of graduate students learning to administer the Wechsler scales have generally shown that training is not associated with the development of scoring proficiency. Many studies report on the reduction of aggregated administration and scoring errors, a strategy that does not highlight the reduction of errors on subtests identified as most prone to error. This study evaluated the development of scoring proficiency specifically on the Wechsler (WISC-IV and WAIS-III) Vocabulary, Comprehension, and Similarities subtests during training by comparing a set of 'early test administrations' to 'later test administrations.' Twelve graduate students enrolled in an intelligence-testing course participated in the study. Scoring errors (e.g., incorrect point assignment) were evaluated on the students' actual practice administration test protocols. Errors on all three subtests declined significantly when scoring errors on 'early' sets of Wechsler scales were compared to those made on 'later' sets. However, correcting these subtest scoring errors did not cause significant changes in subtest scaled scores. Implications for clinical instruction and future research are discussed.

Error Reduction Methods for Integrated-path Differential-absorption Lidar Measurements

NASA Technical Reports Server (NTRS)

Chen, Jeffrey R.; Numata, Kenji; Wu, Stewart T.

2012-01-01

We report new modeling and error reduction methods for differential-absorption optical-depth (DAOD) measurements of atmospheric constituents using direct-detection integrated-path differential-absorption lidars. Errors from laser frequency noise are quantified in terms of the line center fluctuation and spectral line shape of the laser pulses, revealing relationships verified experimentally. A significant DAOD bias is removed by introducing a correction factor. Errors from surface height and reflectance variations can be reduced to tolerable levels by incorporating altimetry knowledge and "log after averaging", or by pointing the laser and receiver to a fixed surface spot during each wavelength cycle to shorten the time of "averaging before log".

The error in total error reduction.

PubMed

Witnauer, James E; Urcelay, Gonzalo P; Miller, Ralph R

2014-02-01

Most models of human and animal learning assume that learning is proportional to the discrepancy between a delivered outcome and the outcome predicted by all cues present during that trial (i.e., total error across a stimulus compound). This total error reduction (TER) view has been implemented in connectionist and artificial neural network models to describe the conditions under which weights between units change. Electrophysiological work has revealed that the activity of dopamine neurons is correlated with the total error signal in models of reward learning. Similar neural mechanisms presumably support fear conditioning, human contingency learning, and other types of learning. Using a computational modeling approach, we compared several TER models of associative learning to an alternative model that rejects the TER assumption in favor of local error reduction (LER), which assumes that learning about each cue is proportional to the discrepancy between the delivered outcome and the outcome predicted by that specific cue on that trial. The LER model provided a better fit to the reviewed data than the TER models. Given the superiority of the LER model with the present data sets, acceptance of TER should be tempered. Copyright © 2013 Elsevier Inc. All rights reserved.

Using Free Navigation Reference Points and Prefabricated Bone Plates for Zygoma Fracture Model Surgeries.

PubMed

Wang, Tien-Hsiang; Ma, Hsu; Tseng, Ching-Shiow; Chou, Yi-Hong; Cai, Kun-Lin

Surgical navigation systems have been an important tool in maxillofacial surgery, helping surgeons create a presurgical plan, locate lesions, and provide guidance. For secondary facial bone reductions, a good presurgical plan and proper execution are the key to success. Previous studies used predetermined markers and screw holes as navigation references; however, unexpected situations may occur, making the predetermined surgical plan unreliable. Instead of determining positions preoperatively, this study proposes a method that surgeons can use intraoperatively to choose surface markers in a more flexible manner. Eight zygomatic fractures were created in four skull models, and preoperative computed tomography (CT) image data were imported into a self-developed navigation program for presurgical planning. This program also calculates the ideal positions of navigation references points for screw holes. During reduction surgery, markers on fractured bone are selected, registered, and calculated as free navigation reference points (FNRPs). The surface markers and FNRPs are used to monitor the position of the dislocated bone. Titanium bone plates were prefabricated on stereolithography models for osteosynthesis. Two reductions with only FNRPs, as well as six reductions with FNRPs and prefabricated bone plates, were successfully performed. Postoperative CT data were obtained, and surgical errors in the six-reduction group were evaluated. The average deviation from the screw hole drilling positions was 0.92 ± 0.38 mm. The average deviation included displacement and rotation of the zygomas. The mean displacement was 0.83 ± 0.38 mm, and the average rotations around the x, y, and z axes were 0.66 ± 0.59°, 0.77 ± 0.54°, and 0.79 ± 0.42°, respectively. The results show that combining presurgical planning and the developed navigation program to generate FNRPs for assisting in secondary zygoma reduction is an accurate and practical method. Further study is necessary to prove its clinical value.

PAPR reduction in FBMC using an ACE-based linear programming optimization

NASA Astrophysics Data System (ADS)

van der Neut, Nuan; Maharaj, Bodhaswar TJ; de Lange, Frederick; González, Gustavo J.; Gregorio, Fernando; Cousseau, Juan

2014-12-01

This paper presents four novel techniques for peak-to-average power ratio (PAPR) reduction in filter bank multicarrier (FBMC) modulation systems. The approach extends on current PAPR reduction active constellation extension (ACE) methods, as used in orthogonal frequency division multiplexing (OFDM), to an FBMC implementation as the main contribution. The four techniques introduced can be split up into two: linear programming optimization ACE-based techniques and smart gradient-project (SGP) ACE techniques. The linear programming (LP)-based techniques compensate for the symbol overlaps by utilizing a frame-based approach and provide a theoretical upper bound on achievable performance for the overlapping ACE techniques. The overlapping ACE techniques on the other hand can handle symbol by symbol processing. Furthermore, as a result of FBMC properties, the proposed techniques do not require side information transmission. The PAPR performance of the techniques is shown to match, or in some cases improve, on current PAPR techniques for FBMC. Initial analysis of the computational complexity of the SGP techniques indicates that the complexity issues with PAPR reduction in FBMC implementations can be addressed. The out-of-band interference introduced by the techniques is investigated. As a result, it is shown that the interference can be compensated for, whilst still maintaining decent PAPR performance. Additional results are also provided by means of a study of the PAPR reduction of the proposed techniques at a fixed clipping probability. The bit error rate (BER) degradation is investigated to ensure that the trade-off in terms of BER degradation is not too severe. As illustrated by exhaustive simulations, the SGP ACE-based technique proposed are ideal candidates for practical implementation in systems employing the low-complexity polyphase implementation of FBMC modulators. The methods are shown to offer significant PAPR reduction and increase the feasibility of FBMC as a replacement modulation system for OFDM.

Landing Technique Improvements After an Aquatic-Based Neuromuscular Training Program in Physically Active Women.

PubMed

Scarneo, Samantha E; Root, Hayley J; Martinez, Jessica C; Denegar, Craig; Casa, Douglas J; Mazerolle, Stephanie M; Dann, Catie L; Aerni, Giselle A; DiStefano, Lindsay J

2017-01-01

Neuromuscular training programs (NTPs) improve landing technique and decrease vertical ground-reaction forces (VGRFs), resulting in injury-risk reduction. NTPs in an aquatic environment may elicit the same improvements as land-based programs with reduced joint stress. To examine the effects of an aquatic NTP on landing technique as measured by the Landing Error Scoring System (LESS) and VGRFs, immediately and 4 mo after the intervention. Repeated measures, pool and laboratory. Fifteen healthy, recreationally active women (age 21 ± 2 y, mass 62.02 ± 8.18 kg, height 164.74 ± 5.97 cm) who demonstrated poor landing technique (LESS-Real Time > 4). All participants completed an aquatic NTP 3 times/wk for 6 wk. Participants' landing technique was evaluated using a jump-landing task immediately before (PRE), immediately after (POST), and 4 mo after (RET) the intervention period. A single rater, blinded to time point, graded all videos using the LESS, which is a valid and reliable movement-screening tool. Peak VGRFs were measured during the stance phase of the jump-landing test. Repeated-measure analyses of variance with planned comparisons were performed to explore differences between time points. LESS scores were lower at POST (4.46 ± 1.69 errors) and at RET (4.2 ± 1.72 errors) than at PRE (6.30 ± 1.78 errors) (P < .01). No significant differences were observed between POST and RET (P > .05). Participants also landed with significantly lower peak VGRFs (P < .01) from PRE (2.69 ± .72 N) to POST (2.23 ± .66 N). The findings introduce evidence that an aquatic NTP improves landing technique and suggest that improvements are retained over time. These results show promise of using an aquatic NTP when there is a desire to reduce joint loading, such as early stages of rehabilitation, to improve biomechanics and reduce injury risk.

Attitude errors arising from antenna/satellite altitude errors - Recognition and reduction

NASA Technical Reports Server (NTRS)

Godbey, T. W.; Lambert, R.; Milano, G.

1972-01-01

A review is presented of the three basic types of pulsed radar altimeter designs, as well as the source and form of altitude bias errors arising from antenna/satellite attitude errors in each design type. A quantitative comparison of the three systems was also made.

Adaptation of catch-up saccades during the initiation of smooth pursuit eye movements.

PubMed

Schütz, Alexander C; Souto, David

2011-04-01

Reduction of retinal speed and alignment of the line of sight are believed to be the respective primary functions of smooth pursuit and saccadic eye movements. As the eye muscles strength can change in the short-term, continuous adjustments of motor signals are required to achieve constant accuracy. While adaptation of saccade amplitude to systematic position errors has been extensively studied, we know less about the adaptive response to position errors during smooth pursuit initiation, when target motion has to be taken into account to program saccades, and when position errors at the saccade endpoint could also be corrected by increasing pursuit velocity. To study short-term adaptation (250 adaptation trials) of tracking eye movements, we introduced a position error during the first catch-up saccade made during the initiation of smooth pursuit-in a ramp-step-ramp paradigm. The target position was either shifted in the direction of the horizontally moving target (forward step), against it (backward step) or orthogonally to it (vertical step). Results indicate adaptation of catch-up saccade amplitude to back and forward steps. With vertical steps, saccades became oblique, by an inflexion of the early or late saccade trajectory. With a similar time course, post-saccadic pursuit velocity was increased in the step direction, adding further evidence that under some conditions pursuit and saccades can act synergistically to reduce position errors.

Does Wechsler Intelligence Scale administration and scoring proficiency improve during assessment training?

PubMed

Platt, Tyson L; Zachar, Peter; Ray, Glen E; Lobello, Steven G; Underhill, Andrea T

2007-04-01

Studies have found that Wechsler scale administration and scoring proficiency is not easily attained during graduate training. These findings may be related to methodological issues. Using a single-group repeated measures design, this study documents statistically significant, though modest, error reduction on the WAIS-III and WISC-III during a graduate course in assessment. The study design does not permit the isolation of training factors related to error reduction, or assessment of whether error reduction is a function of mere practice. However, the results do indicate that previous study findings of no or inconsistent improvement in scoring proficiency may have been the result of methodological factors. Implications for teaching individual intelligence testing and further research are discussed.

Peak-locking error reduction by birefringent optical diffusers

NASA Astrophysics Data System (ADS)

Kislaya, Ankur; Sciacchitano, Andrea

2018-02-01

The use of optical diffusers for the reduction of peak-locking errors in particle image velocimetry is investigated. The working principle of the optical diffusers is based on the concept of birefringence, where the incoming rays are subject to different deflections depending on the light direction and polarization. The performances of the diffusers are assessed via wind tunnel measurements in uniform flow and wall-bounded turbulence. Comparison with best-practice image defocusing is also conducted. It is found that the optical diffusers yield an increase of the particle image diameter up to 10 µm in the sensor plane. Comparison with reference measurements showed a reduction of both random and systematic errors by a factor of 3, even at low imaging signal-to-noise ratio.

The Impact of a Patient Safety Program on Medical Error Reporting

DTIC Science & Technology

2005-05-01

307 The Impact of a Patient Safety Program on Medical Error Reporting Donald R. Woolever Abstract Background: In response to the occurrence of...a sentinel event—a medical error with serious consequences—Eglin U.S. Air Force (USAF) Regional Hospital developed and implemented a patient safety...communication, teamwork, and reporting. Objective: To determine the impact of a patient safety program on patterns of medical error reporting. Methods: This

SBL-Online: Implementing Studio-Based Learning Techniques in an Online Introductory Programming Course to Address Common Programming Errors and Misconceptions

ERIC Educational Resources Information Center

Polo, Blanca J.

2013-01-01

Much research has been done in regards to student programming errors, online education and studio-based learning (SBL) in computer science education. This study furthers this area by bringing together this knowledge and applying it to proactively help students overcome impasses caused by common student programming errors. This project proposes a…

Software reliability: Application of a reliability model to requirements error analysis

NASA Technical Reports Server (NTRS)

Logan, J.

1980-01-01

The application of a software reliability model having a well defined correspondence of computer program properties to requirements error analysis is described. Requirements error categories which can be related to program structural elements are identified and their effect on program execution considered. The model is applied to a hypothetical B-5 requirement specification for a program module.

Prescription errors before and after introduction of electronic medication alert system in a pediatric emergency department.

PubMed

Sethuraman, Usha; Kannikeswaran, Nirupama; Murray, Kyle P; Zidan, Marwan A; Chamberlain, James M

2015-06-01

Prescription errors occur frequently in pediatric emergency departments (PEDs).The effect of computerized physician order entry (CPOE) with electronic medication alert system (EMAS) on these is unknown. The objective was to compare prescription errors rates before and after introduction of CPOE with EMAS in a PED. The hypothesis was that CPOE with EMAS would significantly reduce the rate and severity of prescription errors in the PED. A prospective comparison of a sample of outpatient, medication prescriptions 5 months before and after CPOE with EMAS implementation (7,268 before and 7,292 after) was performed. Error types and rates, alert types and significance, and physician response were noted. Medication errors were deemed significant if there was a potential to cause life-threatening injury, failure of therapy, or an adverse drug effect. There was a significant reduction in the errors per 100 prescriptions (10.4 before vs. 7.3 after; absolute risk reduction = 3.1, 95% confidence interval [CI] = 2.2 to 4.0). Drug dosing error rates decreased from 8 to 5.4 per 100 (absolute risk reduction = 2.6, 95% CI = 1.8 to 3.4). Alerts were generated for 29.6% of prescriptions, with 45% involving drug dose range checking. The sensitivity of CPOE with EMAS in identifying errors in prescriptions was 45.1% (95% CI = 40.8% to 49.6%), and the specificity was 57% (95% CI = 55.6% to 58.5%). Prescribers modified 20% of the dosing alerts, resulting in the error not reaching the patient. Conversely, 11% of true dosing alerts for medication errors were overridden by the prescribers: 88 (11.3%) resulted in medication errors, and 684 (88.6%) were false-positive alerts. A CPOE with EMAS was associated with a decrease in overall prescription errors in our PED. Further system refinements are required to reduce the high false-positive alert rates. © 2015 by the Society for Academic Emergency Medicine.

When bad things happen: adverse event reporting and disclosure as patient safety and risk management tools in the neonatal intensive care unit.

PubMed

Donn, Steven M; McDonnell, William M

2012-01-01

The Institute of Medicine has recommended a change in culture from "name and blame" to patient safety. This will require system redesign to identify and address errors, establish performance standards, and set safety expectations. This approach, however, is at odds with the present medical malpractice (tort) system. The current system is outcomes-based, meaning that health care providers and institutions are often sued despite providing appropriate care. Nevertheless, the focus should remain to provide the safest patient care. Effective peer review may be hindered by the present tort system. Reporting of medical errors is a key piece of peer review and education, and both anonymous reporting and confidential reporting of errors have potential disadvantages. Diagnostic and treatment errors continue to be the leading sources of allegations of malpractice in pediatrics, and the neonatal intensive care unit is uniquely vulnerable. Most errors result from systems failures rather than human error. Risk management can be an effective process to identify, evaluate, and address problems that may injure patients, lead to malpractice claims, and result in financial losses. Risk management identifies risk or potential risk, calculates the probability of an adverse event arising from a risk, estimates the impact of the adverse event, and attempts to control the risk. Implementation of a successful risk management program requires a positive attitude, sufficient knowledge base, and a commitment to improvement. Transparency in the disclosure of medical errors and a strategy of prospective risk management in dealing with medical errors may result in a substantial reduction in medical malpractice lawsuits, lower litigation costs, and a more safety-conscious environment. Thieme Medical Publishers, Inc.

Evaluate the ability of clinical decision support systems (CDSSs) to improve clinical practice.

PubMed

Ajami, Sima; Amini, Fatemeh

2013-01-01

Prevalence of new diseases, medical science promotion and increase of referring to health care centers, provide a good situation for medical errors growth. Errors can involve medicines, surgery, diagnosis, equipment, or lab reports. Medical errors can occur anywhere in the health care system: In hospitals, clinics, surgery centers, doctors' offices, nursing homes, pharmacies, and patients' homes. According to the Institute of Medicine (IOM), 98,000 people die every year from preventable medical errors. In 2010 from all referred medical error records to Iran Legal Medicine Organization, 46/5% physician and medical team members were known as delinquent. One of new technologies that can reduce medical errors is clinical decision support systems (CDSSs). This study was unsystematic-review study. The literature was searched on evaluate the "ability of clinical decision support systems to improve clinical practice" with the help of library, books, conference proceedings, data bank, and also searches engines available at Google, Google scholar. For our searches, we employed the following keywords and their combinations: medical error, clinical decision support systems, Computer-Based Clinical Decision Support Systems, information technology, information system, health care quality, computer systems in the searching areas of title, keywords, abstract, and full text. In this study, more than 100 articles and reports were collected and 38 of them were selected based on their relevancy. The CDSSs are computer programs, designed for help to health care careers. These systems as a knowledge-based tool could help health care manager in analyze evaluation, improvement and selection of effective solutions in clinical decisions. Therefore, it has a main role in medical errors reduction. The aim of this study was to express ability of the CDSSs to improve

Model reduction of dynamical systems by proper orthogonal decomposition: Error bounds and comparison of methods using snapshots from the solution and the time derivatives [Proper orthogonal decomposition model reduction of dynamical systems: error bounds and comparison of methods using snapshots from the solution and the time derivatives

DOE PAGES

Kostova-Vassilevska, Tanya; Oxberry, Geoffrey M.

2017-09-17

In this study, we consider two proper orthogonal decomposition (POD) methods for dimension reduction of dynamical systems. The first method (M1) uses only time snapshots of the solution, while the second method (M2) augments the snapshot set with time-derivative snapshots. The goal of the paper is to analyze and compare the approximation errors resulting from the two methods by using error bounds. We derive several new bounds of the error from POD model reduction by each of the two methods. The new error bounds involve a multiplicative factor depending on the time steps between the snapshots. For method M1 themore » factor depends on the second power of the time step, while for method 2 the dependence is on the fourth power of the time step, suggesting that method M2 can be more accurate for small between-snapshot intervals. However, three other factors also affect the size of the error bounds. These include (i) the norm of the second (for M1) and fourth derivatives (M2); (ii) the first neglected singular value and (iii) the spectral properties of the projection of the system’s Jacobian in the reduced space. Because of the interplay of these factors neither method is more accurate than the other in all cases. Finally, we present numerical examples demonstrating that when the number of collected snapshots is small and the first neglected singular value has a value of zero, method M2 results in a better approximation.« less

Model reduction of dynamical systems by proper orthogonal decomposition: Error bounds and comparison of methods using snapshots from the solution and the time derivatives [Proper orthogonal decomposition model reduction of dynamical systems: error bounds and comparison of methods using snapshots from the solution and the time derivatives

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kostova-Vassilevska, Tanya; Oxberry, Geoffrey M.

In this study, we consider two proper orthogonal decomposition (POD) methods for dimension reduction of dynamical systems. The first method (M1) uses only time snapshots of the solution, while the second method (M2) augments the snapshot set with time-derivative snapshots. The goal of the paper is to analyze and compare the approximation errors resulting from the two methods by using error bounds. We derive several new bounds of the error from POD model reduction by each of the two methods. The new error bounds involve a multiplicative factor depending on the time steps between the snapshots. For method M1 themore » factor depends on the second power of the time step, while for method 2 the dependence is on the fourth power of the time step, suggesting that method M2 can be more accurate for small between-snapshot intervals. However, three other factors also affect the size of the error bounds. These include (i) the norm of the second (for M1) and fourth derivatives (M2); (ii) the first neglected singular value and (iii) the spectral properties of the projection of the system’s Jacobian in the reduced space. Because of the interplay of these factors neither method is more accurate than the other in all cases. Finally, we present numerical examples demonstrating that when the number of collected snapshots is small and the first neglected singular value has a value of zero, method M2 results in a better approximation.« less

Reduction in Hospital-Wide Clinical Laboratory Specimen Identification Errors following Process Interventions: A 10-Year Retrospective Observational Study

PubMed Central

Ning, Hsiao-Chen; Lin, Chia-Ni; Chiu, Daniel Tsun-Yee; Chang, Yung-Ta; Wen, Chiao-Ni; Peng, Shu-Yu; Chu, Tsung-Lan; Yu, Hsin-Ming; Wu, Tsu-Lan

2016-01-01

Background Accurate patient identification and specimen labeling at the time of collection are crucial steps in the prevention of medical errors, thereby improving patient safety. Methods All patient specimen identification errors that occurred in the outpatient department (OPD), emergency department (ED), and inpatient department (IPD) of a 3,800-bed academic medical center in Taiwan were documented and analyzed retrospectively from 2005 to 2014. To reduce such errors, the following series of strategies were implemented: a restrictive specimen acceptance policy for the ED and IPD in 2006; a computer-assisted barcode positive patient identification system for the ED and IPD in 2007 and 2010, and automated sample labeling combined with electronic identification systems introduced to the OPD in 2009. Results Of the 2000345 specimens collected in 2005, 1023 (0.0511%) were identified as having patient identification errors, compared with 58 errors (0.0015%) among 3761238 specimens collected in 2014, after serial interventions; this represents a 97% relative reduction. The total number (rate) of institutional identification errors contributed from the ED, IPD, and OPD over a 10-year period were 423 (0.1058%), 556 (0.0587%), and 44 (0.0067%) errors before the interventions, and 3 (0.0007%), 52 (0.0045%) and 3 (0.0001%) after interventions, representing relative 99%, 92% and 98% reductions, respectively. Conclusions Accurate patient identification is a challenge of patient safety in different health settings. The data collected in our study indicate that a restrictive specimen acceptance policy, computer-generated positive identification systems, and interdisciplinary cooperation can significantly reduce patient identification errors. PMID:27494020

Computerized Generation and Simulation of Meshing and Contact of New Type of Novikov-Wildhaber Helical Gears

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Feng, Pin-Hao; Lagutin, Sergei A.

2000-01-01

In this report, we propose a new geometry for low-noise, increased-strength helical gears of the Novikov-Wildhaber type. Contact stresses are reduced as a result of their convex-concave gear tooth surfaces. The gear tooth surfaces are crowned in the profile direction to localize bearing contact and in the longitudinal direction to obtain a parabolic function of transmission errors. Such a function results in the reduction of noise and vibrations. Methods for the generation of the proposed gear tooth surfaces by grinding and hobbing are considered, and a tooth contact analysis (TCA) computer program to simulate meshing and contact is applied. The report also investigates the influence of misalignment on transmission errors and shift of bearing contact. Numerical examples to illustrate the developed approaches are proposed. The proposed geometry was patented by Ford/UIC (Serial Number 09-340-824, pending) on June 28, 1999.

Eliciting management action: Using THERP to highlight human factors deficiencies for trip reduction programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuld, R.; Cybert, S.

Methods and criteria for performing human factors evaluations of plant systems and procedures are well developed and available. For a design review to produce a positive impact on operations, however, it is not enough to simply document deficiences and solutions. The results must be presented to management in a clear and compelling form that will direct attention to the heart of a problem and present proposed solutions in terms of explicit, quantified cost/benefits. A proactive program of trip reduction provides an excellent opportunity to accomplish human factors-related upgrades. As an evaluative context, trip reduction imposes a uniform goodness criterion onmore » all situations: the probability of inadvertent plant trip. This in turn means that findings can be compared in terms of a common quantitative reference point: the cost of an inadvertent shutdown. To interpret human factors deficiencies in terms of trip probabilities, the Technique for Human Error Rate Prediction (THERP) can be used. THERP provides an accessible compilation of human reliability data for generic, discrete task elements. Sequences of such values are combined in standard event trees to determine the probability of failure (e.g., trip) for a given evolution. THERP is widely accepted as one of the best available alternatives for assessing human reliability.« less

A manual for a laboratory information management system (LIMS) for light stable isotopes

USGS Publications Warehouse

Coplen, Tyler B.

1997-01-01

The reliability and accuracy of isotopic data can be improved by utilizing database software to (i) store information about samples, (ii) store the results of mass spectrometric isotope-ratio analyses of samples, (iii) calculate analytical results using standardized algorithms stored in a database, (iv) normalize stable isotopic data to international scales using isotopic reference materials, and (v) generate multi-sheet paper templates for convenient sample loading of automated mass-spectrometer sample preparation manifolds. Such a database program is presented herein. Major benefits of this system include (i) an increase in laboratory efficiency, (ii) reduction in the use of paper, (iii) reduction in workload due to the elimination or reduction of retyping of data by laboratory personnel, and (iv) decreased errors in data reported to sample submitters. Such a database provides a complete record of when and how often laboratory reference materials have been analyzed and provides a record of what correction factors have been used through time. It provides an audit trail for stable isotope laboratories. Since the original publication of the manual for LIMS for Light Stable Isotopes, the isotopes 3 H, 3 He, and 14 C, and the chlorofluorocarbons (CFCs), CFC-11, CFC-12, and CFC-113, have been added to this program.

A manual for a Laboratory Information Management System (LIMS) for light stable isotopes

USGS Publications Warehouse

Coplen, Tyler B.

1998-01-01

The reliability and accuracy of isotopic data can be improved by utilizing database software to (i) store information about samples, (ii) store the results of mass spectrometric isotope-ratio analyses of samples, (iii) calculate analytical results using standardized algorithms stored in a database, (iv) normalize stable isotopic data to international scales using isotopic reference materials, and (v) generate multi-sheet paper templates for convenient sample loading of automated mass-spectrometer sample preparation manifolds. Such a database program is presented herein. Major benefits of this system include (i) an increase in laboratory efficiency, (ii) reduction in the use of paper, (iii) reduction in workload due to the elimination or reduction of retyping of data by laboratory personnel, and (iv) decreased errors in data reported to sample submitters. Such a database provides a complete record of when and how often laboratory reference materials have been analyzed and provides a record of what correction factors have been used through time. It provides an audit trail for stable isotope laboratories. Since the original publication of the manual for LIMS for Light Stable Isotopes, the isotopes 3 H, 3 He, and 14 C, and the chlorofluorocarbons (CFCs), CFC-11, CFC-12, and CFC-113, have been added to this program.

Error reduction, patient safety and institutional ethics committees.

PubMed

Meaney, Mark E

2004-01-01

Institutional ethics committees remain largely absent from the literature on error reduction and patient safety. In this paper, the author endeavors to fill the gap. As noted in the Hastings Center's recent report, "Promoting Patient Safety," the occurrence of medical error involves complex web of multiple factors. Human misstep is certainly one such factor, but not the only one. This paper builds on the Hastings Center's report in arguing that institutional ethics committees ought to play an integral role in the transformation of a "culture of blame" to a "culture of safety" in healthcare delivery.

Floating-point system quantization errors in digital control systems

NASA Technical Reports Server (NTRS)

Phillips, C. L.

1973-01-01

The results are reported of research into the effects on system operation of signal quantization in a digital control system. The investigation considered digital controllers (filters) operating in floating-point arithmetic in either open-loop or closed-loop systems. An error analysis technique is developed, and is implemented by a digital computer program that is based on a digital simulation of the system. As an output the program gives the programing form required for minimum system quantization errors (either maximum of rms errors), and the maximum and rms errors that appear in the system output for a given bit configuration. The program can be integrated into existing digital simulations of a system.

Keeping the "continuous" in continuous quality improvement: exploring perceived outcomes of CQI program use in community pharmacy.

PubMed

Boyle, Todd A; Bishop, Andrea C; Duggan, Kellie; Reid, Carolyn; Mahaffey, Thomas; MacKinnon, Neil J; Mahaffey, Amelia

2014-01-01

Given the significant potential of continuous quality improvement (CQI) programs in enhancing overall levels of patient safety, community pharmacies in North America are under increasing pressure to have a formal and documented CQI program in place. However, while such initiatives may seem great on paper, in practice the outcomes of such programs to community pharmacy practice remain unclear. To explore the perceived outcomes identified by community pharmacies that adopted and actively used a standardized (i.e., common across pharmacies) CQI program for at least 1 year and to develop a framework for how such outcomes were achieved. A multi-site study of SafetyNET-Rx, a standardized and technologically sophisticated (e.g., online reporting of medication errors to a national database) CQI program, involving community pharmacies in Nova Scotia, Canada, was performed. During the summer and fall of 2011, 22 interviews were conducted with the CQI facilitators in 12 Nova Scotia community pharmacies; equally split between independent/banners and corporate chains. Of the CQI facilitators, 14 were pharmacists, while the remaining eight were pharmacy technicians. Thematic analysis following the procedures presented by Braun and Clarke was adopted to identify and explore the major outcomes. Results of the thematic analysis highlighted a number of perceived outcomes from the use of a standardized CQI program in community pharmacies, specifically: (1) perceived reduction in the number of medication errors that were occurring in the pharmacy, (2) increased awareness/confidence of individual actions related to dispensing, (3) increased understanding of the dispensing and related processes/workflow, (4) increased openness to talking about medication errors among pharmacy staff, and (5) quality and safety becoming more entrenched in the workflow (e.g., staff is more aware of their roles and responsibilities in patient safety and confident that the dispensing processes are safe and reliable). In achieving such outcomes, pharmacies had to balance customizing the CQI program to address a number of operational challenges, with ensuring that the core standardized components remained in place. This research identified the perceived outcomes of CQI program use by CQI facilitators. Additionally, the findings are incorporated into a framework for CQI implementation that can be used by pharmacy managers, corporate head offices, and regulatory authorities to leverage greater CQI adoption and success. Copyright © 2014 Elsevier Inc. All rights reserved.

Analysis of Darwin Rainfall Data: Implications on Sampling Strategy

NASA Technical Reports Server (NTRS)

Rafael, Qihang Li; Bras, Rafael L.; Veneziano, Daniele

1996-01-01

Rainfall data collected by radar in the vicinity of Darwin, Australia, have been analyzed in terms of their mean, variance, autocorrelation of area-averaged rain rate, and diurnal variation. It is found that, when compared with the well-studied GATE (Global Atmospheric Research Program Atlantic Tropical Experiment) data, Darwin rainfall has larger coefficient of variation (CV), faster reduction of CV with increasing area size, weaker temporal correlation, and a strong diurnal cycle and intermittence. The coefficient of variation for Darwin rainfall has larger magnitude and exhibits larger spatial variability over the sea portion than over the land portion within the area of radar coverage. Stationary, and nonstationary models have been used to study the sampling errors associated with space-based rainfall measurement. The nonstationary model shows that the sampling error is sensitive to the starting sampling time for some sampling frequencies, due to the diurnal cycle of rain, but not for others. Sampling experiments using data also show such sensitivity. When the errors are averaged over starting time, the results of the experiments and the stationary and nonstationary models match each other very closely. In the small areas for which data are available for I>oth Darwin and GATE, the sampling error is expected to be larger for Darwin due to its larger CV.

The effectiveness of risk management program on pediatric nurses' medication error.

PubMed

Dehghan-Nayeri, Nahid; Bayat, Fariba; Salehi, Tahmineh; Faghihzadeh, Soghrat

2013-09-01

Medication therapy is one of the most complex and high-risk clinical processes that nurses deal with. Medication error is the most common type of error that brings about damage and death to patients, especially pediatric ones. However, these errors are preventable. Identifying and preventing undesirable events leading to medication errors are the main risk management activities. The aim of this study was to investigate the effectiveness of a risk management program on the pediatric nurses' medication error rate. This study is a quasi-experimental one with a comparison group. In this study, 200 nurses were recruited from two main pediatric hospitals in Tehran. In the experimental hospital, we applied the risk management program for a period of 6 months. Nurses of the control hospital did the hospital routine schedule. A pre- and post-test was performed to measure the frequency of the medication error events. SPSS software, t-test, and regression analysis were used for data analysis. After the intervention, the medication error rate of nurses at the experimental hospital was significantly lower (P < 0.001) and the error-reporting rate was higher (P < 0.007) compared to before the intervention and also in comparison to the nurses of the control hospital. Based on the results of this study and taking into account the high-risk nature of the medical environment, applying the quality-control programs such as risk management can effectively prevent the occurrence of the hospital undesirable events. Nursing mangers can reduce the medication error rate by applying risk management programs. However, this program cannot succeed without nurses' cooperation.

Programming Errors in APL.

ERIC Educational Resources Information Center

Kearsley, Greg P.

This paper discusses and provides some preliminary data on errors in APL programming. Data were obtained by analyzing listings of 148 complete and partial APL sessions collected from student terminal rooms at the University of Alberta. Frequencies of errors for the various error messages are tabulated. The data, however, are limited because they…

Interventions to reduce medication errors in neonatal care: a systematic review

PubMed Central

Nguyen, Minh-Nha Rhylie; Mosel, Cassandra

2017-01-01

Background: Medication errors represent a significant but often preventable cause of morbidity and mortality in neonates. The objective of this systematic review was to determine the effectiveness of interventions to reduce neonatal medication errors. Methods: A systematic review was undertaken of all comparative and noncomparative studies published in any language, identified from searches of PubMed and EMBASE and reference-list checking. Eligible studies were those investigating the impact of any medication safety interventions aimed at reducing medication errors in neonates in the hospital setting. Results: A total of 102 studies were identified that met the inclusion criteria, including 86 comparative and 16 noncomparative studies. Medication safety interventions were classified into six themes: technology (n = 38; e.g. electronic prescribing), organizational (n = 16; e.g. guidelines, policies, and procedures), personnel (n = 13; e.g. staff education), pharmacy (n = 9; e.g. clinical pharmacy service), hazard and risk analysis (n = 8; e.g. error detection tools), and multifactorial (n = 18; e.g. any combination of previous interventions). Significant variability was evident across all included studies, with differences in intervention strategies, trial methods, types of medication errors evaluated, and how medication errors were identified and evaluated. Most studies demonstrated an appreciable risk of bias. The vast majority of studies (>90%) demonstrated a reduction in medication errors. A similar median reduction of 50–70% in medication errors was evident across studies included within each of the identified themes, but findings varied considerably from a 16% increase in medication errors to a 100% reduction in medication errors. Conclusion: While neonatal medication errors can be reduced through multiple interventions aimed at improving the medication use process, no single intervention appeared clearly superior. Further research is required to evaluate the relative cost-effectiveness of the various medication safety interventions to facilitate decisions regarding uptake and implementation into clinical practice. PMID:29387337

A Support System for Error Correction Questions in Programming Education

ERIC Educational Resources Information Center

Hachisu, Yoshinari; Yoshida, Atsushi

2014-01-01

For supporting the education of debugging skills, we propose a system for generating error correction questions of programs and checking the correctness. The system generates HTML files for answering questions and CGI programs for checking answers. Learners read and answer questions on Web browsers. For management of error injection, we have…

78 FR 39730 - Medicare Program; Notification of Closure of Teaching Hospitals and Opportunity To Apply for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-02

..., Medicare--Hospital Insurance; and Program No. 93.774, Medicare-- Supplementary Medical Insurance Program.... SUMMARY: This document corrects a typographical error that appeared in the notice published in the Federal... typographical error that is identified and corrected in the Correction of Errors section below. II. Summary of...

LACIE performance predictor final operational capability program description, volume 1

NASA Technical Reports Server (NTRS)

1976-01-01

The program EPHEMS computes the orbital parameters for up to two vehicles orbiting the earth for up to 549 days. The data represents a continuous swath about the earth, producing tables which can be used to determine when and if certain land segments will be covered. The program GRID processes NASA's climatology tape to obtain the weather indices along with associated latitudes and longitudes. The program LUMP takes substrata historical data and sample segment ID, crop window, crop window error and statistical data, checks for valid input parameters and generates the segment ID file, crop window file and the substrata historical file. Finally, the System Error Executive (SEE) Program checks YES error and truth data, CAMS error data, and signature extension data for validity and missing elements. A message is printed for each error found.

A multifaceted program for improving quality of care in intensive care units: IATROREF study.

PubMed

Garrouste-Orgeas, Maite; Soufir, Lilia; Tabah, Alexis; Schwebel, Carole; Vesin, Aurelien; Adrie, Christophe; Thuong, Marie; Timsit, Jean Francois

2012-02-01

To test the effects of three multifaceted safety programs designed to decrease insulin administration errors, anticoagulant prescription and administration errors, and errors leading to accidental removal of endotracheal tubes and central venous catheters, respectively. Medical errors and adverse events are associated with increased mortality in intensive care patients, indicating an urgent need for prevention programs. Multicenter cluster-randomized study. One medical intensive care unit in a university hospital and two medical-surgical intensive care units in community hospitals belonging to the Outcomerea Study Group. Consecutive patients >18 yrs admitted from January 2007 to January 2008 to the intensive care units. We tested three multifaceted safety programs vs. standard care in random order, each over 2.5 months, after a 1.5-month observation period. Incidence rates of medical errors/1000 patient-days in the multifaceted safety program and standard-care groups were compared using adjusted hierarchical models. In 2117 patients with 15,014 patient-days, 8520 medical errors (567.5/1000 patient-days) were reported, including 1438 adverse events (16.9%, 95.8/1000 patient-days). The insulin multifaceted safety program significantly decreased errors during implementation (risk ratio 0.65; 95% confidence interval [CI] 0.52-0.82; p = .0003) and after implementation (risk ratio 0.51; 95% CI 0.35-0.73; p = .0004). A significant Hawthorne effect was found. The accidental tube/catheter removal multifaceted safety program decreased errors significantly during implementation (odds ratio [OR] 0.34; 95% CI 0.15-0.81; p = .01]) and nonsignificantly after implementation (OR 1.65; 95% CI 0.78-3.48). The anticoagulation multifaceted safety program was not significantly effective (OR 0.64; 95% CI 0.26-1.59) but produced a significant Hawthorne effect. A multifaceted program was effective in preventing insulin errors and accidental tube/catheter removal. Significant Hawthorne effects occurred, emphasizing the need for appropriately designed studies before definitively implementing strategies. clinicaltrials.gov Identifier: NCT00461461.

Approaches to reducing photon dose calculation errors near metal implants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Jessie Y.; Followill, David S.; Howell, Reb

Purpose: Dose calculation errors near metal implants are caused by limitations of the dose calculation algorithm in modeling tissue/metal interface effects as well as density assignment errors caused by imaging artifacts. The purpose of this study was to investigate two strategies for reducing dose calculation errors near metal implants: implementation of metal-based energy deposition kernels in the convolution/superposition (C/S) dose calculation method and use of metal artifact reduction methods for computed tomography (CT) imaging. Methods: Both error reduction strategies were investigated using a simple geometric slab phantom with a rectangular metal insert (composed of titanium or Cerrobend), as well asmore » two anthropomorphic phantoms (one with spinal hardware and one with dental fillings), designed to mimic relevant clinical scenarios. To assess the dosimetric impact of metal kernels, the authors implemented titanium and silver kernels in a commercial collapsed cone C/S algorithm. To assess the impact of CT metal artifact reduction methods, the authors performed dose calculations using baseline imaging techniques (uncorrected 120 kVp imaging) and three commercial metal artifact reduction methods: Philips Healthcare’s O-MAR, GE Healthcare’s monochromatic gemstone spectral imaging (GSI) using dual-energy CT, and GSI with metal artifact reduction software (MARS) applied. For the simple geometric phantom, radiochromic film was used to measure dose upstream and downstream of metal inserts. For the anthropomorphic phantoms, ion chambers and radiochromic film were used to quantify the benefit of the error reduction strategies. Results: Metal kernels did not universally improve accuracy but rather resulted in better accuracy upstream of metal implants and decreased accuracy directly downstream. For the clinical cases (spinal hardware and dental fillings), metal kernels had very little impact on the dose calculation accuracy (<1.0%). Of the commercial CT artifact reduction methods investigated, the authors found that O-MAR was the most consistent method, resulting in either improved dose calculation accuracy (dental case) or little impact on calculation accuracy (spine case). GSI was unsuccessful at reducing the severe artifacts caused by dental fillings and had very little impact on calculation accuracy. GSI with MARS on the other hand gave mixed results, sometimes introducing metal distortion and increasing calculation errors (titanium rectangular implant and titanium spinal hardware) but other times very successfully reducing artifacts (Cerrobend rectangular implant and dental fillings). Conclusions: Though successful at improving dose calculation accuracy upstream of metal implants, metal kernels were not found to substantially improve accuracy for clinical cases. Of the commercial artifact reduction methods investigated, O-MAR was found to be the most consistent candidate for all-purpose CT simulation imaging. The MARS algorithm for GSI should be used with caution for titanium implants, larger implants, and implants located near heterogeneities as it can distort the size and shape of implants and increase calculation errors.« less

Tenth NASTRAN User's Colloquium

NASA Technical Reports Server (NTRS)

1982-01-01

The development of the NASTRAN computer program, a general purpose finite element computer code for structural analysis, was discussed. The application and development of NASTRAN is presented in the following topics: improvements and enhancements; developments of pre and postprocessors; interactive review system; the use of harmonic expansions in magnetic field problems; improving a dynamic model with test data using Linwood; solution of axisymmetric fluid structure interaction problems; large displacements and stability analysis of nonlinear propeller structures; prediction of bead area contact load at the tire wheel interface; elastic plastic analysis of an overloaded breech ring; finite element solution of torsion and other 2-D Poisson equations; new capability for elastic aircraft airloads; usage of substructuring analysis in the get away special program; solving symmetric structures with nonsymmetric loads; evaluation and reduction of errors induced by Guyan transformation.

Real-time flutter analysis

NASA Technical Reports Server (NTRS)

Walker, R.; Gupta, N.

1984-01-01

The important algorithm issues necessary to achieve a real time flutter monitoring system; namely, the guidelines for choosing appropriate model forms, reduction of the parameter convergence transient, handling multiple modes, the effect of over parameterization, and estimate accuracy predictions, both online and for experiment design are addressed. An approach for efficiently computing continuous-time flutter parameter Cramer-Rao estimate error bounds were developed. This enables a convincing comparison of theoretical and simulation results, as well as offline studies in preparation for a flight test. Theoretical predictions, simulation and flight test results from the NASA Drones for Aerodynamic and Structural Test (DAST) Program are compared.

Spatial and temporal variability of the overall error of National Atmospheric Deposition Program measurements determined by the USGS collocated-sampler program, water years 1989-2001

USGS Publications Warehouse

Wetherbee, G.A.; Latysh, N.E.; Gordon, J.D.

2005-01-01

Data from the U.S. Geological Survey (USGS) collocated-sampler program for the National Atmospheric Deposition Program/National Trends Network (NADP/NTN) are used to estimate the overall error of NADP/NTN measurements. Absolute errors are estimated by comparison of paired measurements from collocated instruments. Spatial and temporal differences in absolute error were identified and are consistent with longitudinal distributions of NADP/NTN measurements and spatial differences in precipitation characteristics. The magnitude of error for calcium, magnesium, ammonium, nitrate, and sulfate concentrations, specific conductance, and sample volume is of minor environmental significance to data users. Data collected after a 1994 sample-handling protocol change are prone to less absolute error than data collected prior to 1994. Absolute errors are smaller during non-winter months than during winter months for selected constituents at sites where frozen precipitation is common. Minimum resolvable differences are estimated for different regions of the USA to aid spatial and temporal watershed analyses.

ISO Key Project: Exploring The Full Range of Quasar/AGN Properties

NASA Technical Reports Server (NTRS)

Wilkes, Belinda; West, Donald K. (Technical Monitor)

2002-01-01

While most of the work on this program has been completed, as previously reported, the portion of the program dealing with the sub topic of ISO LWS data analysis and reduction for the LWS Extragalactic Science Team and its leader, Dr. Howard Smith, is still active. This program in fact continues to generate results, and newly available computer modeling has extended the value of the datasets, As a result the team has requested and been granted an obtained a no-cost extension to this program, through December 31, 2003. The essence of the proposal is to perform ISO spectroscopic studies, including data analysis and modeling, of star formation regions using an ensemble of archival space-based data from the Infrared Space Observatory's Long Wavelength Spectrometer and Short Wavelength Spectrometer, but including as well some other spectroscopic data bases. Four kinds of regions are considered in the studies: (1) disks around more evolved objects; (2) young, low or high mass pre-main sequence stars in star formation regions; (3) star formation in external, bright IR galaxies; and (4) the galactic center. One prime focus of the program is the OH lines in the far infrared. The program has the following goals: (1) refine the data analysis of ISO observations, to obtain deeper and better SNR results on selected sources. The ISO data itself underwent "pipeline 10" reductions in early 2001, and additional "hands-on data reduction packages" were supplied by the ISO teams in 2001. The Fabry-Perot database in particularly sensitive to noise can slight calibration errors. (2) model the atomic and molecular line shapes, in particular the OH lines, using revised Monte-Carlo techniques developed by the SWAS team at the Center for Astrophysics; (3) attend scientific meetings and workshops; (4) do E&PO activities related to infrared astrophysics and/or spectroscopy.

Exploring Reactions to Pilot Reliability Certification and Changing Attitudes on the Reduction of Errors

ERIC Educational Resources Information Center

Boedigheimer, Dan

2010-01-01

Approximately 70% of aviation accidents are attributable to human error. The greatest opportunity for further improving aviation safety is found in reducing human errors in the cockpit. The purpose of this quasi-experimental, mixed-method research was to evaluate whether there was a difference in pilot attitudes toward reducing human error in the…

Energy and Quality-Aware Multimedia Signal Processing

NASA Astrophysics Data System (ADS)

Emre, Yunus

Today's mobile devices have to support computation-intensive multimedia applications with a limited energy budget. In this dissertation, we present architecture level and algorithm-level techniques that reduce energy consumption of these devices with minimal impact on system quality. First, we present novel techniques to mitigate the effects of SRAM memory failures in JPEG2000 implementations operating in scaled voltages. We investigate error control coding schemes and propose an unequal error protection scheme tailored for JPEG2000 that reduces overhead without affecting the performance. Furthermore, we propose algorithm-specific techniques for error compensation that exploit the fact that in JPEG2000 the discrete wavelet transform outputs have larger values for low frequency subband coefficients and smaller values for high frequency subband coefficients. Next, we present use of voltage overscaling to reduce the data-path power consumption of JPEG codecs. We propose an algorithm-specific technique which exploits the characteristics of the quantized coefficients after zig-zag scan to mitigate errors introduced by aggressive voltage scaling. Third, we investigate the effect of reducing dynamic range for datapath energy reduction. We analyze the effect of truncation error and propose a scheme that estimates the mean value of the truncation error during the pre-computation stage and compensates for this error. Such a scheme is very effective for reducing the noise power in applications that are dominated by additions and multiplications such as FIR filter and transform computation. We also present a novel sum of absolute difference (SAD) scheme that is based on most significant bit truncation. The proposed scheme exploits the fact that most of the absolute difference (AD) calculations result in small values, and most of the large AD values do not contribute to the SAD values of the blocks that are selected. Such a scheme is highly effective in reducing the energy consumption of motion estimation and intra-prediction kernels in video codecs. Finally, we present several hybrid energy-saving techniques based on combination of voltage scaling, computation reduction and dynamic range reduction that further reduce the energy consumption while keeping the performance degradation very low. For instance, a combination of computation reduction and dynamic range reduction for Discrete Cosine Transform shows on average, 33% to 46% reduction in energy consumption while incurring only 0.5dB to 1.5dB loss in PSNR.

Effects of Optical Blur Reduction on Equivalent Intrinsic Blur

PubMed Central

Valeshabad, Ali Kord; Wanek, Justin; McAnany, J. Jason; Shahidi, Mahnaz

2015-01-01

Purpose To determine the effect of optical blur reduction on equivalent intrinsic blur, an estimate of the blur within the visual system, by comparing optical and equivalent intrinsic blur before and after adaptive optics (AO) correction of wavefront error. Methods Twelve visually normal individuals (age; 31 ± 12 years) participated in this study. Equivalent intrinsic blur (σint) was derived using a previously described model. Optical blur (σopt) due to high-order aberrations was quantified by Shack-Hartmann aberrometry and minimized using AO correction of wavefront error. Results σopt and σint were significantly reduced and visual acuity (VA) was significantly improved after AO correction (P ≤ 0.004). Reductions in σopt and σint were linearly dependent on the values before AO correction (r ≥ 0.94, P ≤ 0.002). The reduction in σint was greater than the reduction in σopt, although it was marginally significant (P = 0.05). σint after AO correlated significantly with σint before AO (r = 0.92, P < 0.001) and the two parameters were related linearly with a slope of 0.46. Conclusions Reduction in equivalent intrinsic blur was greater than the reduction in optical blur due to AO correction of wavefront error. This finding implies that VA in subjects with high equivalent intrinsic blur can be improved beyond that expected from the reduction in optical blur alone. PMID:25785538

Effects of optical blur reduction on equivalent intrinsic blur.

PubMed

Kord Valeshabad, Ali; Wanek, Justin; McAnany, J Jason; Shahidi, Mahnaz

2015-04-01

To determine the effect of optical blur reduction on equivalent intrinsic blur, an estimate of the blur within the visual system, by comparing optical and equivalent intrinsic blur before and after adaptive optics (AO) correction of wavefront error. Twelve visually normal subjects (mean [±SD] age, 31 [±12] years) participated in this study. Equivalent intrinsic blur (σint) was derived using a previously described model. Optical blur (σopt) caused by high-order aberrations was quantified by Shack-Hartmann aberrometry and minimized using AO correction of wavefront error. σopt and σint were significantly reduced and visual acuity was significantly improved after AO correction (p ≤ 0.004). Reductions in σopt and σint were linearly dependent on the values before AO correction (r ≥ 0.94, p ≤ 0.002). The reduction in σint was greater than the reduction in σopt, although it was marginally significant (p = 0.05). σint after AO correlated significantly with σint before AO (r = 0.92, p < 0.001), and the two parameters were related linearly with a slope of 0.46. Reduction in equivalent intrinsic blur was greater than the reduction in optical blur after AO correction of wavefront error. This finding implies that visual acuity in subjects with high equivalent intrinsic blur can be improved beyond that expected from the reduction in optical blur alone.

Methods and apparatus using commutative error detection values for fault isolation in multiple node computers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Almasi, Gheorghe; Blumrich, Matthias Augustin; Chen, Dong

Methods and apparatus perform fault isolation in multiple node computing systems using commutative error detection values for--example, checksums--to identify and to isolate faulty nodes. When information associated with a reproducible portion of a computer program is injected into a network by a node, a commutative error detection value is calculated. At intervals, node fault detection apparatus associated with the multiple node computer system retrieve commutative error detection values associated with the node and stores them in memory. When the computer program is executed again by the multiple node computer system, new commutative error detection values are created and stored inmore » memory. The node fault detection apparatus identifies faulty nodes by comparing commutative error detection values associated with reproducible portions of the application program generated by a particular node from different runs of the application program. Differences in values indicate a possible faulty node.« less

Digital Mirror Device Application in Reduction of Wave-front Phase Errors

PubMed Central

Zhang, Yaping; Liu, Yan; Wang, Shuxue

2009-01-01

In order to correct the image distortion created by the mixing/shear layer, creative and effectual correction methods are necessary. First, a method combining adaptive optics (AO) correction with a digital micro-mirror device (DMD) is presented. Second, performance of an AO system using the Phase Diverse Speckle (PDS) principle is characterized in detail. Through combining the DMD method with PDS, a significant reduction in wavefront phase error is achieved in simulations and experiments. This kind of complex correction principle can be used to recovery the degraded images caused by unforeseen error sources. PMID:22574016

Critical Findings: Attempts at Reducing Notification Errors.

PubMed

Shahriari, Mona; Liu, Li; Yousem, David M

2016-11-01

Ineffective communication of critical findings (CFs) is a patient safety issue. The aim of this study was to assess whether a feedback program for faculty members failing to correctly report CFs would lead to improved compliance. Fifty randomly selected reports were reviewed by the chief of neuroradiology each month for 42 months. Errors included (1) not calling for a CF, (2) not identifying a CF as such, (3) mischaracterizing non-CFs as CFs, and (4) calling for non-CFs. The number of appropriately handled and mishandled reports in each month was recorded. The trend of error reduction after the division chief provided feedback in the subsequent months was evaluated, and the equality of time interval between errors was tested. Among 2,100 reports, 49 (2.3%) were handled inappropriately. Among non-CF reports, 98.97% (1,817 of 1,836) were appropriately not called and not flagged, and 88.64% (234 of 264) of CF reports were called and flagged appropriately. The error rate during the 11th through 32nd months of review (1.28%) was significantly lower than the error rate in the first 10 months of review (3.98%) (P = .001). This benefit lasted for 21 months. Review and giving feedback to radiologists increased their compliance with the CF protocol and decreased deviations from standard operating procedures for about 2 years (from month 10 to month 32). Developing new ideas for improving CF policy compliance may be required at 2- to 3-year intervals to provide continuous quality improvement. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Effects of a direct refill program for automated dispensing cabinets on medication-refill errors.

PubMed

Helmons, Pieter J; Dalton, Ashley J; Daniels, Charles E

2012-10-01

The effects of a direct refill program for automated dispensing cabinets (ADCs) on medication-refill errors were studied. This study was conducted in designated acute care areas of a 386-bed academic medical center. A wholesaler-to-ADC direct refill program, consisting of prepackaged delivery of medications and bar-code-assisted ADC refilling, was implemented in the inpatient pharmacy of the medical center in September 2009. Medication-refill errors in 26 ADCs from the general medicine units, the infant special care unit, the surgical and burn intensive care units, and intermediate units were assessed before and after the implementation of this program. Medication-refill errors were defined as an ADC pocket containing the wrong drug, wrong strength, or wrong dosage form. ADC refill errors decreased by 77%, from 62 errors per 6829 refilled pockets (0.91%) to 8 errors per 3855 refilled pockets (0.21%) (p < 0.0001). The predominant error type detected before the intervention was the incorrect medication (wrong drug, wrong strength, or wrong dosage form) in the ADC pocket. Of the 54 incorrect medications found before the intervention, 38 (70%) were loaded in a multiple-drug drawer. After the implementation of the new refill process, 3 of the 5 incorrect medications were loaded in a multiple-drug drawer. There were 3 instances of expired medications before and only 1 expired medication after implementation of the program. A redesign of the ADC refill process using a wholesaler-to-ADC direct refill program that included delivery of prepackaged medication and bar-code-assisted refill significantly decreased the occurrence of ADC refill errors.

Goldmann tonometer error correcting prism: clinical evaluation.

PubMed

McCafferty, Sean; Lim, Garrett; Duncan, William; Enikov, Eniko T; Schwiegerling, Jim; Levine, Jason; Kew, Corin

2017-01-01

Clinically evaluate a modified applanating surface Goldmann tonometer prism designed to substantially negate errors due to patient variability in biomechanics. A modified Goldmann prism with a correcting applanation tonometry surface (CATS) was mathematically optimized to minimize the intraocular pressure (IOP) measurement error due to patient variability in corneal thickness, stiffness, curvature, and tear film adhesion force. A comparative clinical study of 109 eyes measured IOP with CATS and Goldmann prisms. The IOP measurement differences between the CATS and Goldmann prisms were correlated to corneal thickness, hysteresis, and curvature. The CATS tonometer prism in correcting for Goldmann central corneal thickness (CCT) error demonstrated a reduction to <±2 mmHg in 97% of a standard CCT population. This compares to only 54% with CCT error <±2 mmHg using the Goldmann prism. Equal reductions of ~50% in errors due to corneal rigidity and curvature were also demonstrated. The results validate the CATS prism's improved accuracy and expected reduced sensitivity to Goldmann errors without IOP bias as predicted by mathematical modeling. The CATS replacement for the Goldmann prism does not change Goldmann measurement technique or interpretation.

Effectiveness of Toyota process redesign in reducing thyroid gland fine-needle aspiration error.

PubMed

Raab, Stephen S; Grzybicki, Dana Marie; Sudilovsky, Daniel; Balassanian, Ronald; Janosky, Janine E; Vrbin, Colleen M

2006-10-01

Our objective was to determine whether the Toyota Production System process redesign resulted in diagnostic error reduction for patients who underwent cytologic evaluation of thyroid nodules. In this longitudinal, nonconcurrent cohort study, we compared the diagnostic error frequency of a thyroid aspiration service before and after implementation of error reduction initiatives consisting of adoption of a standardized diagnostic terminology scheme and an immediate interpretation service. A total of 2,424 patients underwent aspiration. Following terminology standardization, the false-negative rate decreased from 41.8% to 19.1% (P = .006), the specimen nondiagnostic rate increased from 5.8% to 19.8% (P < .001), and the sensitivity increased from 70.2% to 90.6% (P < .001). Cases with an immediate interpretation had a lower noninterpretable specimen rate than those without immediate interpretation (P < .001). Toyota process change led to significantly fewer diagnostic errors for patients who underwent thyroid fine-needle aspiration.

Identifying Novice Student Programming Misconceptions and Errors from Summative Assessments

ERIC Educational Resources Information Center

Veerasamy, Ashok Kumar; D'Souza, Daryl; Laakso, Mikko-Jussi

2016-01-01

This article presents a study aimed at examining the novice student answers in an introductory programming final e-exam to identify misconceptions and types of errors. Our study used the Delphi concept inventory to identify student misconceptions and skill, rule, and knowledge-based errors approach to identify the types of errors made by novices…

Considerations for use of the RORA program to estimate ground-water recharge from streamflow records

USGS Publications Warehouse

Rutledge, A.T.

2000-01-01

The RORA program can be used to estimate ground-water recharge in a basin from analysis of a streamflow record. The program can be appropriate for use if the ground-water flow system is characterized by diffuse areal recharge to the water table and discharge to a stream. The use of the program requires an estimate of a recession index, which is the time required for ground-water discharge to recede by one log cycle after recession becomes linear or near-linear on the semilog hydrograph. Although considerable uncertainty is inherent in the recession index, the results of the RORA program may not be sensitive to this variable. Testing shows that the program can yield consistent estimates under conditions that include leakage to or from deeper aquifers and ground-water evapotranspiration. These tests indicate that RORA estimates the net recharge, which is recharge to the water table minus leakage to a deeper aquifer, or recharge minus ground-water evapotranspiration. Before the program begins making calculations it designates days that fit a requirement of antecedent recession, and these days are used in calculations. The program user might increase the antecedent-recession requirement above its default value to reduce the influence of errors that are caused by direct-surface runoff, but other errors can result from the reduction in the number of peaks detected. To obtain an understanding of flow systems, results from the RORA program might be used in conjunction with other methods such as analysis of ground-water levels, estimates of ground-water discharge from other forms of hydrograph separation, and low-flow variables. Relations among variables may be complex for a variety of reasons; for example, there may not be a unique relation between ground-water level and ground-water discharge, ground-water recharge and discharge are not synchronous, and low-flow variables can be related to other factors such as the recession index.

Putting into practice error management theory: Unlearning and learning to manage action errors in construction.

PubMed

Love, Peter E D; Smith, Jim; Teo, Pauline

2018-05-01

Error management theory is drawn upon to examine how a project-based organization, which took the form of a program alliance, was able to change its established error prevention mindset to one that enacted a learning mindfulness that provided an avenue to curtail its action errors. The program alliance was required to unlearn its existing routines and beliefs to accommodate the practices required to embrace error management. As a result of establishing an error management culture the program alliance was able to create a collective mindfulness that nurtured learning and supported innovation. The findings provide a much-needed context to demonstrate the relevance of error management theory to effectively address rework and safety problems in construction projects. The robust theoretical underpinning that is grounded in practice and presented in this paper provides a mechanism to engender learning from errors, which can be utilized by construction organizations to improve the productivity and performance of their projects. Copyright © 2018 Elsevier Ltd. All rights reserved.

Preparations for Global Precipitation Measurement(GPM)Ground Validation

NASA Technical Reports Server (NTRS)

Bidwell, S. W.; Bibyk, I. K.; Duming, J. F.; Everett, D. F.; Smith, E. A.; Wolff, D. B.

2004-01-01

The Global Precipitation Measurement (GPM) program is an international partnership led by the National Aeronautics and Space Administration (NASA) and the Japan Aerospace Exploration Agency (JAXA). GPM will improve climate, weather, and hydro-meterorological forecasts through more frequent and more accurate measurement of precipitation across the globe. This paper describes the concept and the preparations for Ground Validation within the GPM program. Ground Validation (GV) plays a critical role in the program by investigating and quantitatively assessing the errors within the satellite retrievals. These quantitative estimates of retrieval errors will assist the scientific community by bounding the errors within their research products. The two fundamental requirements of the GPM Ground Validation program are: (1) error characterization of the precipitation retrievals and (2) continual improvement of the satellite retrieval algorithms. These two driving requirements determine the measurements, instrumentation, and location for ground observations. This paper describes GV plans for estimating the systematic and random components of retrieval error and for characterizing the spatial and temporal structure of the error. This paper describes the GPM program for algorithm improvement in which error models are developed and experimentally explored to uncover the physical causes of errors within the retrievals. GPM will ensure that information gained through Ground Validation is applied to future improvements in the spaceborne retrieval algorithms. This paper discusses the potential locations for validation measurement and research, the anticipated contributions of GPM's international partners, and the interaction of Ground Validation with other GPM program elements.

Unforced errors and error reduction in tennis

PubMed Central

Brody, H

2006-01-01

Only at the highest level of tennis is the number of winners comparable to the number of unforced errors. As the average player loses many more points due to unforced errors than due to winners by an opponent, if the rate of unforced errors can be reduced, it should lead to an increase in points won. This article shows how players can improve their game by understanding and applying the laws of physics to reduce the number of unforced errors. PMID:16632568

The introduction of an acute physiological support service for surgical patients is an effective error reduction strategy.

PubMed

Clarke, D L; Kong, V Y; Naidoo, L C; Furlong, H; Aldous, C

2013-01-01

Acute surgical patients are particularly vulnerable to human error. The Acute Physiological Support Team (APST) was created with the twin objectives of identifying high-risk acute surgical patients in the general wards and reducing both the incidence of error and impact of error on these patients. A number of error taxonomies were used to understand the causes of human error and a simple risk stratification system was adopted to identify patients who are particularly at risk of error. During the period November 2012-January 2013 a total of 101 surgical patients were cared for by the APST at Edendale Hospital. The average age was forty years. There were 36 females and 65 males. There were 66 general surgical patients and 35 trauma patients. Fifty-six patients were referred on the day of their admission. The average length of stay in the APST was four days. Eleven patients were haemo-dynamically unstable on presentation and twelve were clinically septic. The reasons for referral were sepsis,(4) respiratory distress,(3) acute kidney injury AKI (38), post-operative monitoring (39), pancreatitis,(3) ICU down-referral,(7) hypoxia,(5) low GCS,(1) coagulopathy.(1) The mortality rate was 13%. A total of thirty-six patients experienced 56 errors. A total of 143 interventions were initiated by the APST. These included institution or adjustment of intravenous fluids (101), blood transfusion,(12) antibiotics,(9) the management of neutropenic sepsis,(1) central line insertion,(3) optimization of oxygen therapy,(7) correction of electrolyte abnormality,(8) correction of coagulopathy.(2) CONCLUSION: Our intervention combined current taxonomies of error with a simple risk stratification system and is a variant of the defence in depth strategy of error reduction. We effectively identified and corrected a significant number of human errors in high-risk acute surgical patients. This audit has helped understand the common sources of error in the general surgical wards and will inform on-going error reduction initiatives. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Influence of age, sex, technique, and exercise program on movement patterns after an anterior cruciate ligament injury prevention program in youth soccer players.

PubMed

DiStefano, Lindsay J; Padua, Darin A; DiStefano, Michael J; Marshall, Stephen W

2009-03-01

Anterior cruciate ligament (ACL) injury prevention programs show promising results with changing movement; however, little information exists regarding whether a program designed for an individual's movements may be effective or how baseline movements may affect outcomes. A program designed to change specific movements would be more effective than a "one-size-fits-all" program. Greatest improvement would be observed among individuals with the most baseline error. Subjects of different ages and sexes respond similarly. Randomized controlled trial; Level of evidence, 1. One hundred seventy-three youth soccer players from 27 teams were randomly assigned to a generalized or stratified program. Subjects were videotaped during jump-landing trials before and after the program and were assessed using the Landing Error Scoring System (LESS), which is a valid clinical movement analysis tool. A high LESS score indicates more errors. Generalized players performed the same exercises, while the stratified players performed exercises to correct their initial movement errors. Change scores were compared between groups of varying baseline errors, ages, sexes, and programs. Subjects with the highest baseline LESS score improved the most (95% CI, -3.4 to -2.0). High school subjects (95% CI, -1.7 to -0.98) improved their technique more than pre-high school subjects (95% CI, -1.0 to -0.4). There was no difference between the programs or sexes. Players with the greatest amount of movement errors experienced the most improvement. A program's effectiveness may be enhanced if this population is targeted.

Treatment of ocean tide aliasing in the context of a next generation gravity field mission

NASA Astrophysics Data System (ADS)

Hauk, Markus; Pail, Roland

2018-07-01

Current temporal gravity field solutions from Gravity Recovery and Climate Experiment (GRACE) suffer from temporal aliasing errors due to undersampling of signal to be recovered (e.g. hydrology), uncertainties in the de-aliasing models (usually atmosphere and ocean) and imperfect ocean tide models. Especially the latter will be one of the most limiting factors in determining high-resolution temporal gravity fields from future gravity missions such as GRACE Follow-On and Next-Generation Gravity Missions (NGGM). In this paper a method to co-parametrize ocean tide parameters of the eight main tidal constituents over time spans of several years is analysed and assessed. Numerical closed-loop simulations of low-low satellite-to-satellite-tracking missions for a single polar pair and a double pair Bender-type formation are performed, using time variable geophysical background models and noise assumptions for new generation instrument technology. Compared to the single pair mission, results show a reduction of tide model errors up to 70 per cent for dedicated tidal constituents due to an enhanced spatial and temporal sampling and error isotropy for the double pair constellation. Extending the observation period from 1 to 3 yr leads to a further reduction of tidal errors up to 60 per cent for certain constituents, and considering non-tidal mass changes during the estimation process leads to reductions of tidal errors between 20 and 80 per cent. As part of a two-step approach, the estimated tide model is used for de-aliasing during gravity field retrieval in a second iteration, resulting in more than 50 per cent reduction of ocean tide aliasing errors for a NGGM Bender-type formation.

Treatment of ocean tide aliasing in the context of a next generation gravity field mission

NASA Astrophysics Data System (ADS)

Hauk, Markus; Pail, Roland

2018-04-01

Current temporal gravity field solutions from GRACE suffer from temporal aliasing errors due to under-sampling of signal to be recovered (e.g. hydrology), uncertainties in the de-aliasing models (usually atmosphere and ocean), and imperfect ocean tide models. Especially the latter will be one of the most limiting factors in determining high resolution temporal gravity fields from future gravity missions such as GRACE Follow-on and Next-Generation Gravity Missions (NGGM). In this paper a method to co-parameterize ocean tide parameters of the 8 main tidal constituents over time spans of several years is analysed and assessed. Numerical closed-loop simulations of low-low satellite-to-satellite-tracking missions for a single polar pair and a double pair Bender-type formation are performed, using time variable geophysical background models and noise assumptions for new generation instrument technology. Compared to the single pair mission, results show a reduction of tide model errors up to 70 per cent for dedicated tidal constituents due to an enhanced spatial and temporal sampling and error isotropy for the double pair constellation. Extending the observation period from one to three years leads to a further reduction of tidal errors up to 60 per cent for certain constituents, and considering non-tidal mass changes during the estimation process leads to reductions of tidal errors between 20 per cent and 80 per cent. As part of a two-step approach, the estimated tide model is used for de-aliasing during gravity field retrieval in a second iteration, resulting in more than 50 per cent reduction of ocean tide aliasing errors for a NGGM Bender-type formation.

Parallel computers - Estimate errors caused by imprecise data

NASA Technical Reports Server (NTRS)

Kreinovich, Vladik; Bernat, Andrew; Villa, Elsa; Mariscal, Yvonne

1991-01-01

A new approach to the problem of estimating errors caused by imprecise data is proposed in the context of software engineering. A software device is used to produce an ideal solution to the problem, when the computer is capable of computing errors of arbitrary programs. The software engineering aspect of this problem is to describe a device for computing the error estimates in software terms and then to provide precise numbers with error estimates to the user. The feasibility of the program capable of computing both some quantity and its error estimate in the range of possible measurement errors is demonstrated.

Innovations in Medication Preparation Safety and Wastage Reduction: Use of a Workflow Management System in a Pediatric Hospital.

PubMed

Davis, Stephen Jerome; Hurtado, Josephine; Nguyen, Rosemary; Huynh, Tran; Lindon, Ivan; Hudnall, Cedric; Bork, Sara

2017-01-01

Background: USP <797> regulatory requirements have mandated that pharmacies improve aseptic techniques and cleanliness of the medication preparation areas. In addition, the Institute for Safe Medication Practices (ISMP) recommends that technology and automation be used as much as possible for preparing and verifying compounded sterile products. Objective: To determine the benefits associated with the implementation of the workflow management system, such as reducing medication preparation and delivery errors, reducing quantity and frequency of medication errors, avoiding costs, and enhancing the organization's decision to move toward positive patient identification (PPID). Methods: At Texas Children's Hospital, data were collected and analyzed from January 2014 through August 2014 in the pharmacy areas in which the workflow management system would be implemented. Data were excluded for September 2014 during the workflow management system oral liquid implementation phase. Data were collected and analyzed from October 2014 through June 2015 to determine whether the implementation of the workflow management system reduced the quantity and frequency of reported medication errors. Data collected and analyzed during the study period included the quantity of doses prepared, number of incorrect medication scans, number of doses discontinued from the workflow management system queue, and the number of doses rejected. Data were collected and analyzed to identify patterns of incorrect medication scans, to determine reasons for rejected medication doses, and to determine the reduction in wasted medications. Results: During the 17-month study period, the pharmacy department dispensed 1,506,220 oral liquid and injectable medication doses. From October 2014 through June 2015, the pharmacy department dispensed 826,220 medication doses that were prepared and checked via the workflow management system. Of those 826,220 medication doses, there were 16 reported incorrect volume errors. The error rate after the implementation of the workflow management system averaged 8.4%, which was a 1.6% reduction. After the implementation of the workflow management system, the average number of reported oral liquid medication and injectable medication errors decreased to 0.4 and 0.2 times per week, respectively. Conclusion: The organization was able to achieve its purpose and goal of improving the provision of quality pharmacy care through optimal medication use and safety by reducing medication preparation errors. Error rates decreased and the workflow processes were streamlined, which has led to seamless operations within the pharmacy department. There has been significant cost avoidance and waste reduction and enhanced interdepartmental satisfaction due to the reduction of reported medication errors.

Scalable effective-temperature reduction for quantum annealers via nested quantum annealing correction

NASA Astrophysics Data System (ADS)

Vinci, Walter; Lidar, Daniel A.

2018-02-01

Nested quantum annealing correction (NQAC) is an error-correcting scheme for quantum annealing that allows for the encoding of a logical qubit into an arbitrarily large number of physical qubits. The encoding replaces each logical qubit by a complete graph of degree C . The nesting level C represents the distance of the error-correcting code and controls the amount of protection against thermal and control errors. Theoretical mean-field analyses and empirical data obtained with a D-Wave Two quantum annealer (supporting up to 512 qubits) showed that NQAC has the potential to achieve a scalable effective-temperature reduction, Teff˜C-η , with 0 <η ≤2 . We confirm that this scaling is preserved when NQAC is tested on a D-Wave 2000Q device (supporting up to 2048 qubits). In addition, we show that NQAC can also be used in sampling problems to lower the effective-temperature of a quantum annealer. Such effective-temperature reduction is relevant for machine-learning applications. Since we demonstrate that NQAC achieves error correction via a reduction of the effective-temperature of the quantum annealing device, our results address the problem of the "temperature scaling law for quantum annealers," which requires the temperature of quantum annealers to be reduced as problems of larger sizes are attempted to be solved.

An analytically linearized helicopter model with improved modeling accuracy

NASA Technical Reports Server (NTRS)

Jensen, Patrick T.; Curtiss, H. C., Jr.; Mckillip, Robert M., Jr.

1991-01-01

An analytically linearized model for helicopter flight response including rotor blade dynamics and dynamic inflow, that was recently developed, was studied with the objective of increasing the understanding, the ease of use, and the accuracy of the model. The mathematical model is described along with a description of the UH-60A Black Hawk helicopter and flight test used to validate the model. To aid in utilization of the model for sensitivity analysis, a new, faster, and more efficient implementation of the model was developed. It is shown that several errors in the mathematical modeling of the system caused a reduction in accuracy. These errors in rotor force resolution, trim force and moment calculation, and rotor inertia terms were corrected along with improvements to the programming style and documentation. Use of a trim input file to drive the model is examined. Trim file errors in blade twist, control input phase angle, coning and lag angles, main and tail rotor pitch, and uniform induced velocity, were corrected. Finally, through direct comparison of the original and corrected model responses to flight test data, the effect of the corrections on overall model output is shown.

Reducing errors benefits the field-based learning of a fundamental movement skill in children.

PubMed

Capio, C M; Poolton, J M; Sit, C H P; Holmstrom, M; Masters, R S W

2013-03-01

Proficient fundamental movement skills (FMS) are believed to form the basis of more complex movement patterns in sports. This study examined the development of the FMS of overhand throwing in children through either an error-reduced (ER) or error-strewn (ES) training program. Students (n = 216), aged 8-12 years (M = 9.16, SD = 0.96), practiced overhand throwing in either a program that reduced errors during practice (ER) or one that was ES. ER program reduced errors by incrementally raising the task difficulty, while the ES program had an incremental lowering of task difficulty. Process-oriented assessment of throwing movement form (Test of Gross Motor Development-2) and product-oriented assessment of throwing accuracy (absolute error) were performed. Changes in performance were examined among children in the upper and lower quartiles of the pretest throwing accuracy scores. ER training participants showed greater gains in movement form and accuracy, and performed throwing more effectively with a concurrent secondary cognitive task. Movement form improved among girls, while throwing accuracy improved among children with low ability. Reduced performance errors in FMS training resulted in greater learning than a program that did not restrict errors. Reduced cognitive processing costs (effective dual-task performance) associated with such approach suggest its potential benefits for children with developmental conditions. © 2011 John Wiley & Sons A/S.

Reduction in the write error rate of voltage-induced dynamic magnetization switching using the reverse bias method

NASA Astrophysics Data System (ADS)

Ikeura, Takuro; Nozaki, Takayuki; Shiota, Yoichi; Yamamoto, Tatsuya; Imamura, Hiroshi; Kubota, Hitoshi; Fukushima, Akio; Suzuki, Yoshishige; Yuasa, Shinji

2018-04-01

Using macro-spin modeling, we studied the reduction in the write error rate (WER) of voltage-induced dynamic magnetization switching by enhancing the effective thermal stability of the free layer using a voltage-controlled magnetic anisotropy change. Marked reductions in WER can be achieved by introducing reverse bias voltage pulses both before and after the write pulse. This procedure suppresses the thermal fluctuations of magnetization in the initial and final states. The proposed reverse bias method can offer a new way of improving the writing stability of voltage-driven spintronic devices.

Error reduction and parameter optimization of the TAPIR method for fast T1 mapping.

PubMed

Zaitsev, M; Steinhoff, S; Shah, N J

2003-06-01

A methodology is presented for the reduction of both systematic and random errors in T(1) determination using TAPIR, a Look-Locker-based fast T(1) mapping technique. The relations between various sequence parameters were carefully investigated in order to develop recipes for choosing optimal sequence parameters. Theoretical predictions for the optimal flip angle were verified experimentally. Inversion pulse imperfections were identified as the main source of systematic errors in T(1) determination with TAPIR. An effective remedy is demonstrated which includes extension of the measurement protocol to include a special sequence for mapping the inversion efficiency itself. Copyright 2003 Wiley-Liss, Inc.

Scout trajectory error propagation computer program

NASA Technical Reports Server (NTRS)

Myler, T. R.

1982-01-01

Since 1969, flight experience has been used as the basis for predicting Scout orbital accuracy. The data used for calculating the accuracy consists of errors in the trajectory parameters (altitude, velocity, etc.) at stage burnout as observed on Scout flights. Approximately 50 sets of errors are used in Monte Carlo analysis to generate error statistics in the trajectory parameters. A covariance matrix is formed which may be propagated in time. The mechanization of this process resulted in computer program Scout Trajectory Error Propagation (STEP) and is described herein. Computer program STEP may be used in conjunction with the Statistical Orbital Analysis Routine to generate accuracy in the orbit parameters (apogee, perigee, inclination, etc.) based upon flight experience.

The 3 faces of clinical reasoning: Epistemological explorations of disparate error reduction strategies.

PubMed

Monteiro, Sandra; Norman, Geoff; Sherbino, Jonathan

2018-06-01

There is general consensus that clinical reasoning involves 2 stages: a rapid stage where 1 or more diagnostic hypotheses are advanced and a slower stage where these hypotheses are tested or confirmed. The rapid hypothesis generation stage is considered inaccessible for analysis or observation. Consequently, recent research on clinical reasoning has focused specifically on improving the accuracy of the slower, hypothesis confirmation stage. Three perspectives have developed in this line of research, and each proposes different error reduction strategies for clinical reasoning. This paper considers these 3 perspectives and examines the underlying assumptions. Additionally, this paper reviews the evidence, or lack of, behind each class of error reduction strategies. The first perspective takes an epidemiological stance, appealing to the benefits of incorporating population data and evidence-based medicine in every day clinical reasoning. The second builds on the heuristic and bias research programme, appealing to a special class of dual process reasoning models that theorizes a rapid error prone cognitive process for problem solving with a slower more logical cognitive process capable of correcting those errors. Finally, the third perspective borrows from an exemplar model of categorization that explicitly relates clinical knowledge and experience to diagnostic accuracy. © 2018 John Wiley & Sons, Ltd.

MERLIN: a Franco-German LIDAR space mission for atmospheric methane

NASA Astrophysics Data System (ADS)

Bousquet, P.; Ehret, G.; Pierangelo, C.; Marshall, J.; Bacour, C.; Chevallier, F.; Gibert, F.; Armante, R.; Crevoisier, C. D.; Edouart, D.; Esteve, F.; Julien, E.; Kiemle, C.; Alpers, M.; Millet, B.

2017-12-01

The Methane Remote Sensing Lidar Mission (MERLIN), currently in phase C, is a joint cooperation between France and Germany on the development, launch and operation of a space LIDAR dedicated to the retrieval of total weighted methane (CH4) atmospheric columns. Atmospheric methane is the second most potent anthropogenic greenhouse gas, contributing 20% to climate radiative forcing but also plying an important role in atmospheric chemistry as a precursor of tropospheric ozone and low-stratosphere water vapour. Its short lifetime ( 9 years) and the nature and variety of its anthropogenic sources also offer interesting mitigation options in regards to the 2° objective of the Paris agreement. For the first time, measurements of atmospheric composition will be performed from space thanks to an IPDA (Integrated Path Differential Absorption) LIDAR (Light Detecting And Ranging), with a precision (target ±27 ppb for a 50km aggregation along the trace) and accuracy (target <3.7 ppb at 68%) sufficient to significantly reduce the uncertainties on methane emissions. The very low targeted systematic error target is particularly ambitious compared to current passive methane space mission. It is achievable because of the differential active measurements of MERLIN, which guarantees almost no contamination by aerosols or water vapour cross-sensitivity. As an active mission, MERLIN will deliver global methane weighted columns (XCH4) for all seasons and all latitudes, day and night Here, we recall the MERLIN objectives and mission characteristics. We also propose an end-to-end error analysis, from the causes of random and systematic errors of the instrument, of the platform and of the data treatment, to the error on methane emissions. To do so, we propose an OSSE analysis (observing system simulation experiment) to estimate the uncertainty reduction on methane emissions brought by MERLIN XCH4. The originality of our inversion system is to transfer both random and systematic errors from the observation space to the flux space, thus providing more realistic error reductions than usually provided in OSSE only using the random part of errors. Uncertainty reductions are presented using two different atmospheric transport models, TM3 and LMDZ, and compared with error reduction achieved with the GOSAT passive mission.

A detailed description of the uncertainty analysis for high area ratio rocket nozzle tests at the NASA Lewis Research Center

NASA Technical Reports Server (NTRS)

Davidian, Kenneth J.; Dieck, Ronald H.; Chuang, Isaac

1987-01-01

A preliminary uncertainty analysis was performed for the High Area Ratio Rocket Nozzle test program which took place at the altitude test capsule of the Rocket Engine Test Facility at the NASA Lewis Research Center. Results from the study establish the uncertainty of measured and calculated parameters required for the calculation of rocket engine specific impulse. A generalized description of the uncertainty methodology used is provided. Specific equations and a detailed description of the analysis is presented. Verification of the uncertainty analysis model was performed by comparison with results from the experimental program's data reduction code. Final results include an uncertainty for specific impulse of 1.30 percent. The largest contributors to this uncertainty were calibration errors from the test capsule pressure and thrust measurement devices.

A detailed description of the uncertainty analysis for High Area Ratio Rocket Nozzle tests at the NASA Lewis Research Center

NASA Technical Reports Server (NTRS)

Davidian, Kenneth J.; Dieck, Ronald H.; Chuang, Isaac

1987-01-01

A preliminary uncertainty analysis has been performed for the High Area Ratio Rocket Nozzle test program which took place at the altitude test capsule of the Rocket Engine Test Facility at the NASA Lewis Research Center. Results from the study establish the uncertainty of measured and calculated parameters required for the calculation of rocket engine specific impulse. A generalized description of the uncertainty methodology used is provided. Specific equations and a detailed description of the analysis are presented. Verification of the uncertainty analysis model was performed by comparison with results from the experimental program's data reduction code. Final results include an uncertainty for specific impulse of 1.30 percent. The largest contributors to this uncertainty were calibration errors from the test capsule pressure and thrust measurement devices.

Ecohealth System Dynamic Model as a Planning Tool for the Reduction of Breeding Sites

NASA Astrophysics Data System (ADS)

Respati, T.; Raksanagara, A.; Djuhaeni, H.; Sofyan, A.; Shandriasti, A.

2017-03-01

Dengue is still one of major health problem in Indonesia. Dengue transmission is influenced by dengue prevention and eradication program, community participation, housing environment and climate. The complexity of the disease coupled with limited resources necessitates different approach for prevention methods that include factors contribute to the transmission. One way to prevent the dengue transmission is by reducing the mosquito’s breeding sites. Four factors suspected to influence breeding sites are dengue prevention and eradication program, community participation, housing environment, and weather condition. In order to have an effective program in reducing the breeding site it is needed to have a model which can predict existence of the breeding sites while the four factors under study are controlled. The objective of this study is to develop an Ecohealth model using system dynamic as a planning tool for the reduction of breeding sites to prevent dengue transmission with regard to dengue prevention and eradication program, community participation, housing environment, and weather condition. The methodology is a mixed method study using sequential exploratory design. The study comprised of 3 stages: first a qualitative study to 14 respondents using in-depth interview and 6 respondents for focus group discussion. The results from the first stage was used to develop entomology and household survey questionnaires for second stage conducted in 2036 households across 12 sub districts in Bandung City. Ecohealth system dynamic model was developed using data from first and second stages. Analyses used are thematic analysis for qualitative data; spatial, generalized estimating equation (GEE) and structural equation modeling for quantitative data; also average mean error (AME) and average variance error (AVE) for dynamic system model validation. System dynamic model showed that the most effective approach to eliminate breeding places was by ensuring the availability of basic sanitation for all houses. Weather factors such as precipitation can be compensated with the eradication of breeding sites activities which is conducted as scheduled and at the same time for the whole areas. Conclusion of this study is that dengue prevention and eradication program, community participation, and housing environment contributed to breeding places elimination influenced the existence of the breeding sites. The availability of basic sanitation and breeding places eradication program done timely and collectively are the most effective approach to eradicate breeding sites. Ecohealth dynamic system model can be used as a tool for the planning of breeding sites eradication program to prevent disease transmissions at city level.

Gamma model and its analysis for phase measuring profilometry.

PubMed

Liu, Kai; Wang, Yongchang; Lau, Daniel L; Hao, Qi; Hassebrook, Laurence G

2010-03-01

Phase measuring profilometry is a method of structured light illumination whose three-dimensional reconstructions are susceptible to error from nonunitary gamma in the associated optical devices. While the effects of this distortion diminish with an increasing number of employed phase-shifted patterns, gamma distortion may be unavoidable in real-time systems where the number of projected patterns is limited by the presence of target motion. A mathematical model is developed for predicting the effects of nonunitary gamma on phase measuring profilometry, while also introducing an accurate gamma calibration method and two strategies for minimizing gamma's effect on phase determination. These phase correction strategies include phase corrections with and without gamma calibration. With the reduction in noise, for three-step phase measuring profilometry, analysis of the root mean squared error of the corrected phase will show a 60x reduction in phase error when the proposed gamma calibration is performed versus 33x reduction without calibration.

A Cycle of Redemption in a Medical Error Disclosure and Apology Program.

PubMed

Carmack, Heather J

2014-06-01

Physicians accept that they have an ethical responsibility to disclose and apologize for medical errors; however, when physicians make a medical error, they are often not given the opportunity to disclose and apologize for the mistake. In this article, I explore how one hospital negotiated the aftermath of medical mistakes through a disclosure and apology program. Specifically, I used Burke's cycle of redemption to position the hospital's disclosure and apology program as a redemption process and explore how the hospital physicians and administrators worked through the experiences of disclosing and apologizing for medical errors. © The Author(s) 2014.

Missing texture reconstruction method based on error reduction algorithm using Fourier transform magnitude estimation scheme.

PubMed

Ogawa, Takahiro; Haseyama, Miki

2013-03-01

A missing texture reconstruction method based on an error reduction (ER) algorithm, including a novel estimation scheme of Fourier transform magnitudes is presented in this brief. In our method, Fourier transform magnitude is estimated for a target patch including missing areas, and the missing intensities are estimated by retrieving its phase based on the ER algorithm. Specifically, by monitoring errors converged in the ER algorithm, known patches whose Fourier transform magnitudes are similar to that of the target patch are selected from the target image. In the second approach, the Fourier transform magnitude of the target patch is estimated from those of the selected known patches and their corresponding errors. Consequently, by using the ER algorithm, we can estimate both the Fourier transform magnitudes and phases to reconstruct the missing areas.

Reduction in chemotherapy order errors with computerised physician order entry and clinical decision support systems.

PubMed

Aziz, Muhammad Tahir; Ur-Rehman, Tofeeq; Qureshi, Sadia; Bukhari, Nadeem Irfan

Medication errors in chemotherapy are frequent and lead to patient morbidity and mortality, as well as increased rates of re-admission and length of stay, and considerable extra costs. Objective: This study investigated the proposition that computerised chemotherapy ordering reduces the incidence and severity of chemotherapy protocol errors. A computerised physician order entry of chemotherapy order (C-CO) with clinical decision support system was developed in-house, including standardised chemotherapy protocol definitions, automation of pharmacy distribution, clinical checks, labeling and invoicing. A prospective study was then conducted in a C-CO versus paper based chemotherapy order (P-CO) in a 30-bed chemotherapy bay of a tertiary hospital. Both C-CO and P-CO orders, including pharmacoeconomic analysis and the severity of medication errors, were checked and validated by a clinical pharmacist. A group analysis and field trial were also conducted to assess clarity, feasibility and decision making. The C-CO was very usable in terms of its clarity and feasibility. The incidence of medication errors was significantly lower in the C-CO compared with the P-CO (10/3765 [0.26%] versus 134/5514 [2.4%]). There was also a reduction in dispensing time of chemotherapy protocols in the C-CO. The chemotherapy computerisation with clinical decision support system resulted in a significant decrease in the occurrence and severity of medication errors, improvements in chemotherapy dispensing and administration times, and reduction of chemotherapy cost.

Exploration of Two Training Paradigms Using Forced Induced Weight Shifting With the Tethered Pelvic Assist Device to Reduce Asymmetry in Individuals After Stroke: Case Reports.

PubMed

Bishop, Lauri; Khan, Moiz; Martelli, Dario; Quinn, Lori; Stein, Joel; Agrawal, Sunil

2017-10-01

Many robotic devices in rehabilitation incorporate an assist-as-needed haptic guidance paradigm to promote training. This error reduction model, while beneficial for skill acquisition, could be detrimental for long-term retention. Error augmentation (EA) models have been explored as alternatives. A robotic Tethered Pelvic Assist Device has been developed to study force application to the pelvis on gait and was used here to induce weight shift onto the paretic (error reduction) or nonparetic (error augmentation) limb during treadmill training. The purpose of these case reports is to examine effects of training with these two paradigms to reduce load force asymmetry during gait in two individuals after stroke (>6 mos). Participants presented with baseline gait asymmetry, although independent community ambulators. Participants underwent 1-hr trainings for 3 days using either the error reduction or error augmentation model. Outcomes included the Borg rating of perceived exertion scale for treatment tolerance and measures of force and stance symmetry. Both participants tolerated training. Force symmetry (measured on treadmill) improved from pretraining to posttraining (36.58% and 14.64% gains), however, with limited transfer to overground gait measures (stance symmetry gains of 9.74% and 16.21%). Training with the Tethered Pelvic Assist Device device proved feasible to improve force symmetry on the treadmill irrespective of training model. Future work should consider methods to increase transfer to overground gait.

COMPLEX VARIABLE BOUNDARY ELEMENT METHOD: APPLICATIONS.

USGS Publications Warehouse

Hromadka, T.V.; Yen, C.C.; Guymon, G.L.

1985-01-01

The complex variable boundary element method (CVBEM) is used to approximate several potential problems where analytical solutions are known. A modeling result produced from the CVBEM is a measure of relative error in matching the known boundary condition values of the problem. A CVBEM error-reduction algorithm is used to reduce the relative error of the approximation by adding nodal points in boundary regions where error is large. From the test problems, overall error is reduced significantly by utilizing the adaptive integration algorithm.

An error reduction algorithm to improve lidar turbulence estimates for wind energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Newman, Jennifer F.; Clifton, Andrew

Remote-sensing devices such as lidars are currently being investigated as alternatives to cup anemometers on meteorological towers for the measurement of wind speed and direction. Although lidars can measure mean wind speeds at heights spanning an entire turbine rotor disk and can be easily moved from one location to another, they measure different values of turbulence than an instrument on a tower. Current methods for improving lidar turbulence estimates include the use of analytical turbulence models and expensive scanning lidars. While these methods provide accurate results in a research setting, they cannot be easily applied to smaller, vertically profiling lidarsmore » in locations where high-resolution sonic anemometer data are not available. Thus, there is clearly a need for a turbulence error reduction model that is simpler and more easily applicable to lidars that are used in the wind energy industry. In this work, a new turbulence error reduction algorithm for lidars is described. The Lidar Turbulence Error Reduction Algorithm, L-TERRA, can be applied using only data from a stand-alone vertically profiling lidar and requires minimal training with meteorological tower data. The basis of L-TERRA is a series of physics-based corrections that are applied to the lidar data to mitigate errors from instrument noise, volume averaging, and variance contamination. These corrections are applied in conjunction with a trained machine-learning model to improve turbulence estimates from a vertically profiling WINDCUBE v2 lidar. The lessons learned from creating the L-TERRA model for a WINDCUBE v2 lidar can also be applied to other lidar devices. L-TERRA was tested on data from two sites in the Southern Plains region of the United States. The physics-based corrections in L-TERRA brought regression line slopes much closer to 1 at both sites and significantly reduced the sensitivity of lidar turbulence errors to atmospheric stability. The accuracy of machine-learning methods in L-TERRA was highly dependent on the input variables and training dataset used, suggesting that machine learning may not be the best technique for reducing lidar turbulence intensity (TI) error. Future work will include the use of a lidar simulator to better understand how different factors affect lidar turbulence error and to determine how these errors can be reduced using information from a stand-alone lidar.« less

An error reduction algorithm to improve lidar turbulence estimates for wind energy

DOE PAGES

Newman, Jennifer F.; Clifton, Andrew

2017-02-10

Remote-sensing devices such as lidars are currently being investigated as alternatives to cup anemometers on meteorological towers for the measurement of wind speed and direction. Although lidars can measure mean wind speeds at heights spanning an entire turbine rotor disk and can be easily moved from one location to another, they measure different values of turbulence than an instrument on a tower. Current methods for improving lidar turbulence estimates include the use of analytical turbulence models and expensive scanning lidars. While these methods provide accurate results in a research setting, they cannot be easily applied to smaller, vertically profiling lidarsmore » in locations where high-resolution sonic anemometer data are not available. Thus, there is clearly a need for a turbulence error reduction model that is simpler and more easily applicable to lidars that are used in the wind energy industry. In this work, a new turbulence error reduction algorithm for lidars is described. The Lidar Turbulence Error Reduction Algorithm, L-TERRA, can be applied using only data from a stand-alone vertically profiling lidar and requires minimal training with meteorological tower data. The basis of L-TERRA is a series of physics-based corrections that are applied to the lidar data to mitigate errors from instrument noise, volume averaging, and variance contamination. These corrections are applied in conjunction with a trained machine-learning model to improve turbulence estimates from a vertically profiling WINDCUBE v2 lidar. The lessons learned from creating the L-TERRA model for a WINDCUBE v2 lidar can also be applied to other lidar devices. L-TERRA was tested on data from two sites in the Southern Plains region of the United States. The physics-based corrections in L-TERRA brought regression line slopes much closer to 1 at both sites and significantly reduced the sensitivity of lidar turbulence errors to atmospheric stability. The accuracy of machine-learning methods in L-TERRA was highly dependent on the input variables and training dataset used, suggesting that machine learning may not be the best technique for reducing lidar turbulence intensity (TI) error. Future work will include the use of a lidar simulator to better understand how different factors affect lidar turbulence error and to determine how these errors can be reduced using information from a stand-alone lidar.« less

Intelligent Engine Systems Work Element 1.2: Malfunction and Operator Error Reduction

NASA Technical Reports Server (NTRS)

Wiseman, Matthew

2005-01-01

Jet engines, although highly reliable and safe, do experience malfunctions that cause flight delays, passenger stress, and in some cases, in conjunction with inappropriate crew response, contribute to airplane accidents. On rare occasions, the anomalous engine behavior is not recognized until it is too late for the pilots to do anything to prevent or mitigate the resulting engine malfunction causing in-flight shutdowns (IFSDs), aborted takeoffs (ATOs), or loss of thrust control (LOTC). In some cases, the crew response to a myriad of external stimuli and existing training procedures is the source of the problem mentioned above. The problem is the reduction of jet engine malfunctions (IFSDs, ATOs, and LOTC) and inappropriate crew response (PSM+ICR) through the use of evolving and advanced technologies. The solution is to develop the overall system health maintenance architecture, detection and accommodation technologies, processes, and enhanced crew interfaces that would enable a significant reduction in IFSDs, ATOs, and LOTC. This program defines requirements and proposes a preliminary design concept of an architecture that enables the realization of the solution.

[A delayed motor production of open chains of linear strokes presented visually in static and dynamic modes: a comparison between 9 to 11 years old children and adults].

PubMed

Antonova, A A; Absatova, K A; Korneev, A A; Kurgansky, A V

2015-01-01

The production of drawing movements was studied in 29 right-handed children of 9-to-11 years old. The movements were the sequences of horizontal and vertical linear stokes conjoined at right angle (open polygonal chains) referred to throughout the paper as trajectories. The length of a trajectory varied from 4 to 6. The trajectories were presented visually to a subject in static (linedrawing) and dynamic (moving cursor that leaves no trace) modes. The subjects were asked to draw (copy) a trajectory in response to delayed go-signal (short click) as fast as possible without lifting the pen. The production latency time, the average movement duration along a trajectory segment, and overall number of errors committed by a subject during trajectory production were analyzed. A comparison of children's data with similar data in adults (16 subjects) shows the following. First, a substantial reduction in error rate is observed in the age range between 9 and 11 years old for both static and dynamic modes of trajectory presentation, with children of 11 still committing more error than adults. Second, the averaged movement duration shortens with age while the latency time tends to increase. Third, unlike the adults, the children of 9-11 do not show any difference in latency time between static and dynamic modes of visual presentation of trajectories. The difference in trajectory production between adult and children is attributed to the predominant involvement of on-line programming in children and pre-programming in adults.

Global Precipitation Measurement (GPM) Ground Validation: Plans and Preparations

NASA Technical Reports Server (NTRS)

Schwaller, M.; Bidwell, S.; Durning, F. J.; Smith, E.

2004-01-01

The Global Precipitation Measurement (GPM) program is an international partnership led by the National Aeronautics and Space Administration (NASA) and the Japan Aerospace Exploration Agency (JAXA). GPM will improve climate, weather, and hydro-meteorological forecasts through more frequent and more accurate measurement of precipitation across the globe. This paper describes the concept, the planning, and the preparations for Ground Validation within the GPM program. Ground Validation (GV) plays an important role in the program by investigating and quantitatively assessing the errors within the satellite retrievals. These quantitative estimates of retrieval errors will assist the scientific community by bounding the errors within their research products. The two fundamental requirements of the GPM Ground Validation program are: (1) error characterization of the precipitation retrievals and (2) continual improvement of the satellite retrieval algorithms. These two driving requirements determine the measurements, instrumentation, and location for ground observations. This paper outlines GV plans for estimating the systematic and random components of retrieval error and for characterizing the spatial p d temporal structure of the error and plans for algorithm improvement in which error models are developed and experimentally explored to uncover the physical causes of errors within the retrievals. This paper discusses NASA locations for GV measurements as well as anticipated locations from international GPM partners. NASA's primary locations for validation measurements are an oceanic site at Kwajalein Atoll in the Republic of the Marshall Islands and a continental site in north-central Oklahoma at the U.S. Department of Energy's Atmospheric Radiation Measurement Program site.

Safety climate and attitude toward medication error reporting after hospital accreditation in South Korea.

PubMed

Lee, Eunjoo

2016-09-01

This study compared registered nurses' perceptions of safety climate and attitude toward medication error reporting before and after completing a hospital accreditation program. Medication errors are the most prevalent adverse events threatening patient safety; reducing underreporting of medication errors significantly improves patient safety. Safety climate in hospitals may affect medication error reporting. This study employed a longitudinal, descriptive design. Data were collected using questionnaires. A tertiary acute hospital in South Korea undergoing a hospital accreditation program. Nurses, pre- and post-accreditation (217 and 373); response rate: 58% and 87%, respectively. Hospital accreditation program. Perceived safety climate and attitude toward medication error reporting. The level of safety climate and attitude toward medication error reporting increased significantly following accreditation; however, measures of institutional leadership and management did not improve significantly. Participants' perception of safety climate was positively correlated with their attitude toward medication error reporting; this correlation strengthened following completion of the program. Improving hospitals' safety climate increased nurses' medication error reporting; interventions that help hospital administration and managers to provide more supportive leadership may facilitate safety climate improvement. Hospitals and their units should develop more friendly and intimate working environments that remove nurses' fear of penalties. Administration and managers should support nurses who report their own errors. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

From Heuristic to Mathematical Modeling of Drugs Dissolution Profiles: Application of Artificial Neural Networks and Genetic Programming

PubMed Central

Mendyk, Aleksander; Güres, Sinan; Szlęk, Jakub; Wiśniowska, Barbara; Kleinebudde, Peter

2015-01-01

The purpose of this work was to develop a mathematical model of the drug dissolution (Q) from the solid lipid extrudates based on the empirical approach. Artificial neural networks (ANNs) and genetic programming (GP) tools were used. Sensitivity analysis of ANNs provided reduction of the original input vector. GP allowed creation of the mathematical equation in two major approaches: (1) direct modeling of Q versus extrudate diameter (d) and the time variable (t) and (2) indirect modeling through Weibull equation. ANNs provided also information about minimum achievable generalization error and the way to enhance the original dataset used for adjustment of the equations' parameters. Two inputs were found important for the drug dissolution: d and t. The extrudates length (L) was found not important. Both GP modeling approaches allowed creation of relatively simple equations with their predictive performance comparable to the ANNs (root mean squared error (RMSE) from 2.19 to 2.33). The direct mode of GP modeling of Q versus d and t resulted in the most robust model. The idea of how to combine ANNs and GP in order to escape ANNs' black-box drawback without losing their superior predictive performance was demonstrated. Open Source software was used to deliver the state-of-the-art models and modeling strategies. PMID:26101544

From Heuristic to Mathematical Modeling of Drugs Dissolution Profiles: Application of Artificial Neural Networks and Genetic Programming.

PubMed

Mendyk, Aleksander; Güres, Sinan; Jachowicz, Renata; Szlęk, Jakub; Polak, Sebastian; Wiśniowska, Barbara; Kleinebudde, Peter

2015-01-01

The purpose of this work was to develop a mathematical model of the drug dissolution (Q) from the solid lipid extrudates based on the empirical approach. Artificial neural networks (ANNs) and genetic programming (GP) tools were used. Sensitivity analysis of ANNs provided reduction of the original input vector. GP allowed creation of the mathematical equation in two major approaches: (1) direct modeling of Q versus extrudate diameter (d) and the time variable (t) and (2) indirect modeling through Weibull equation. ANNs provided also information about minimum achievable generalization error and the way to enhance the original dataset used for adjustment of the equations' parameters. Two inputs were found important for the drug dissolution: d and t. The extrudates length (L) was found not important. Both GP modeling approaches allowed creation of relatively simple equations with their predictive performance comparable to the ANNs (root mean squared error (RMSE) from 2.19 to 2.33). The direct mode of GP modeling of Q versus d and t resulted in the most robust model. The idea of how to combine ANNs and GP in order to escape ANNs' black-box drawback without losing their superior predictive performance was demonstrated. Open Source software was used to deliver the state-of-the-art models and modeling strategies.

Dosimetric Implications of Residual Tracking Errors During Robotic SBRT of Liver Metastases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Mark; Tuen Mun Hospital, Hong Kong; Grehn, Melanie

Purpose: Although the metric precision of robotic stereotactic body radiation therapy in the presence of breathing motion is widely known, we investigated the dosimetric implications of breathing phase–related residual tracking errors. Methods and Materials: In 24 patients (28 liver metastases) treated with the CyberKnife, we recorded the residual correlation, prediction, and rotational tracking errors from 90 fractions and binned them into 10 breathing phases. The average breathing phase errors were used to shift and rotate the clinical tumor volume (CTV) and planning target volume (PTV) for each phase to calculate a pseudo 4-dimensional error dose distribution for comparison with themore » original planned dose distribution. Results: The median systematic directional correlation, prediction, and absolute aggregate rotation errors were 0.3 mm (range, 0.1-1.3 mm), 0.01 mm (range, 0.00-0.05 mm), and 1.5° (range, 0.4°-2.7°), respectively. Dosimetrically, 44%, 81%, and 92% of all voxels differed by less than 1%, 3%, and 5% of the planned local dose, respectively. The median coverage reduction for the PTV was 1.1% (range in coverage difference, −7.8% to +0.8%), significantly depending on correlation (P=.026) and rotational (P=.005) error. With a 3-mm PTV margin, the median coverage change for the CTV was 0.0% (range, −1.0% to +5.4%), not significantly depending on any investigated parameter. In 42% of patients, the 3-mm margin did not fully compensate for the residual tracking errors, resulting in a CTV coverage reduction of 0.1% to 1.0%. Conclusions: For liver tumors treated with robotic stereotactic body radiation therapy, a safety margin of 3 mm is not always sufficient to cover all residual tracking errors. Dosimetrically, this translates into only small CTV coverage reductions.« less

Operational Data Reduction Procedure for Determining Density and Vertical Structure of the Martian Upper Atmosphere from Mars Global Surveyor Accelerometer Measurements

NASA Technical Reports Server (NTRS)

Cancro, George J.; Tolson, Robert H.; Keating, Gerald M.

1998-01-01

The success of aerobraking by the Mars Global Surveyor (MGS) spacecraft was partly due to the analysis of MGS accelerometer data. Accelerometer data was used to determine the effect of the atmosphere on each orbit, to characterize the nature of the atmosphere, and to predict the atmosphere for future orbits. To interpret the accelerometer data, a data reduction procedure was developed to produce density estimations utilizing inputs from the spacecraft, the Navigation Team, and pre-mission aerothermodynamic studies. This data reduction procedure was based on the calculation of aerodynamic forces from the accelerometer data by considering acceleration due to gravity gradient, solar pressure, angular motion of the MGS, instrument bias, thruster activity, and a vibration component due to the motion of the damaged solar array. Methods were developed to calculate all of the acceleration components including a 4 degree of freedom dynamics model used to gain a greater understanding of the damaged solar array. The total error inherent to the data reduction procedure was calculated as a function of altitude and density considering contributions from ephemeris errors, errors in force coefficient, and instrument errors due to bias and digitization. Comparing the results from this procedure to the data of other MGS Teams has demonstrated that this procedure can quickly and accurately describe the density and vertical structure of the Martian upper atmosphere.

Impact of an antiretroviral stewardship strategy on medication error rates.

PubMed

Shea, Katherine M; Hobbs, Athena Lv; Shumake, Jason D; Templet, Derek J; Padilla-Tolentino, Eimeira; Mondy, Kristin E

2018-05-02

The impact of an antiretroviral stewardship strategy on medication error rates was evaluated. This single-center, retrospective, comparative cohort study included patients at least 18 years of age infected with human immunodeficiency virus (HIV) who were receiving antiretrovirals and admitted to the hospital. A multicomponent approach was developed and implemented and included modifications to the order-entry and verification system, pharmacist education, and a pharmacist-led antiretroviral therapy checklist. Pharmacists performed prospective audits using the checklist at the time of order verification. To assess the impact of the intervention, a retrospective review was performed before and after implementation to assess antiretroviral errors. Totals of 208 and 24 errors were identified before and after the intervention, respectively, resulting in a significant reduction in the overall error rate ( p < 0.001). In the postintervention group, significantly lower medication error rates were found in both patient admissions containing at least 1 medication error ( p < 0.001) and those with 2 or more errors ( p < 0.001). Significant reductions were also identified in each error type, including incorrect/incomplete medication regimen, incorrect dosing regimen, incorrect renal dose adjustment, incorrect administration, and the presence of a major drug-drug interaction. A regression tree selected ritonavir as the only specific medication that best predicted more errors preintervention ( p < 0.001); however, no antiretrovirals reliably predicted errors postintervention. An antiretroviral stewardship strategy for hospitalized HIV patients including prospective audit by staff pharmacists through use of an antiretroviral medication therapy checklist at the time of order verification decreased error rates. Copyright © 2018 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Educating Pharmacy Students to Improve Quality (EPIQ) in Colleges and Schools of Pharmacy

PubMed Central

Myers, Jaclyn; Nash, James D.; Lavigne, Jill E.; Moczygemba, Leticia R.; Plake, Kimberly S.; Quiñones-Boex, Ana C.; Holdford, David; West-Strum, Donna; Warholak, Terri L.

2012-01-01

Objective. To assess course instructors’ and students’ perceptions of the Educating Pharmacy Students and Pharmacists to Improve Quality (EPIQ) curriculum. Methods. Seven colleges and schools of pharmacy that were using the EPIQ program in their curricula agreed to participate in the study. Five of the 7 collected student retrospective pre- and post-intervention questionnaires. Changes in students’ perceptions were evaluated to assess their relationships with demographics and course variables. Instructors who implemented the EPIQ program at each of the 7 colleges and schools were also asked to complete a questionnaire. Results. Scores on all questionnaire items indicated improvement in students’ perceived knowledge of quality improvement. The university the students attended, completion of a class project, and length of coverage of material were significantly related to improvement in the students’ scores. Instructors at all colleges and schools felt the EPIQ curriculum was a strong program that fulfilled the criteria for quality improvement and medication error reduction education. Conclusion The EPIQ program is a viable, turnkey option for colleges and schools of pharmacy to use in teaching students about quality improvement. PMID:22919085

Avoiding Substantive Errors in Individualized Education Program Development

ERIC Educational Resources Information Center

Yell, Mitchell L.; Katsiyannis, Antonis; Ennis, Robin Parks; Losinski, Mickey; Christle, Christine A.

2016-01-01

The purpose of this article is to discuss major substantive errors that school personnel may make when developing students' Individualized Education Programs (IEPs). School IEP team members need to understand the importance of the procedural and substantive requirements of the IEP, have an awareness of the five serious substantive errors that IEP…

An Evaluation of Programmed Treatment-integrity Errors during Discrete-trial Instruction

ERIC Educational Resources Information Center

Carroll, Regina A.; Kodak, Tiffany; Fisher, Wayne W.

2013-01-01

This study evaluated the effects of programmed treatment-integrity errors on skill acquisition for children with an autism spectrum disorder (ASD) during discrete-trial instruction (DTI). In Study 1, we identified common treatment-integrity errors that occur during academic instruction in schools. In Study 2, we simultaneously manipulated 3…

7 CFR 275.23 - Determination of State agency program performance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING... section, the adjusted regressed payment error rate shall be calculated to yield the State agency's payment error rate. The adjusted regressed payment error rate is given by r 1″ + r 2″. (ii) If FNS determines...

76 FR 44010 - Medicare Program; Hospice Wage Index for Fiscal Year 2012; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-22

.... 93.774, Medicare-- Supplementary Medical Insurance Program) Dated: July 15, 2011. Dawn L. Smalls... corrects technical errors that appeared in the notice of CMS ruling published in the Federal Register on... FR 26731), there were technical errors that are identified and corrected in the Correction of Errors...

Graphical user interface simplifies infusion pump programming and enhances the ability to detect pump-related faults.

PubMed

Syroid, Noah; Liu, David; Albert, Robert; Agutter, James; Egan, Talmage D; Pace, Nathan L; Johnson, Ken B; Dowdle, Michael R; Pulsipher, Daniel; Westenskow, Dwayne R

2012-11-01

Drug administration errors are frequent and are often associated with the misuse of IV infusion pumps. One source of these errors may be the infusion pump's user interface. We used failure modes-and-effects analyses to identify programming errors and to guide the design of a new syringe pump user interface. We designed the new user interface to clearly show the pump's operating state simultaneously in more than 1 monitoring location. We evaluated anesthesia residents in laboratory and simulated environments on programming accuracy and error detection between the new user interface and the user interface of a commercially available infusion pump. With the new user interface, we observed the number of programming errors reduced by 81%, the number of keystrokes per task reduced from 9.2 ± 5.0 to 7.5 ± 5.5 (mean ± SD), the time required per task reduced from 18.1 ± 14.1 seconds to 10.9 ± 9.5 seconds and significantly less perceived workload. Residents detected 38 of 70 (54%) of the events with the new user interface and 37 of 70 (53%) with the existing user interface, despite no experience with the new user interface and extensive experience with the existing interface. The number of programming errors and workload were reduced partly because it took less time and fewer keystrokes to program the pump when using the new user interface. Despite minimal training, residents quickly identified preexisting infusion pump problems with the new user interface. Intuitive and easy-to-program infusion pump interfaces may reduce drug administration errors and infusion pump-related adverse events.

Medicaid/CHIP Program; Medicaid Program and Children's Health Insurance Program (CHIP); Changes to the Medicaid Eligibility Quality Control and Payment Error Rate Measurement Programs in Response to the Affordable Care Act. Final rule.

PubMed

2017-07-05

This final rule updates the Medicaid Eligibility Quality Control (MEQC) and Payment Error Rate Measurement (PERM) programs based on the changes to Medicaid and the Children's Health Insurance Program (CHIP) eligibility under the Patient Protection and Affordable Care Act. This rule also implements various other improvements to the PERM program.

Preparatory studies for the WFIRST supernova cosmology measurements

NASA Astrophysics Data System (ADS)

Perlmutter, Saul

In the context of the WFIRST-AFTA Science Definition Team we developed a first version of a supernova program, described in the WFIRST-AFTA SDT report. This program uses the imager to discover supernova candidates and an Integral Field Spectrograph (IFS) to obtain spectrophotometric light curves and higher signal to noise spectra of the supernovae near peak to better characterize the supernovae and thus minimize systematic errors. While this program was judged a robust one, and the estimates of the sensitivity to the cosmological parameters were felt to be reliable, due to limitation of time the analysis was clearly limited in depth on a number of issues. The goal of this proposal is to further develop this program and refine the estimates of the sensitivities to the cosmological parameters using more sophisticated systematic uncertainty models and covariance error matrices that fold in more realistic data concerning observed populations of SNe Ia as well as more realistic instrument models. We propose to develop analysis algorithms and approaches that are needed to build, optimize, and refine the WFIRST instrument and program requirements to accomplish the best supernova cosmology measurements possible. We plan to address the following: a) Use realistic Supernova populations, subclasses and population drift. One bothersome uncertainty with the supernova technique is the possibility of population drift with redshift. We are in a unique position to characterize and mitigate such effects using the spectrophotometric time series of real Type Ia supernovae from the Nearby Supernova Factory (SNfactory). Each supernova in this sample has global galaxy measurements as well as additional local environment information derived from the IFS spectroscopy. We plan to develop methods of coping with this issue, e.g., by selecting similar subsamples of supernovae and allowing additional model flexibility, in order to reduce systematic uncertainties. These studies will allow us to tune details, like the wavelength coverage and S/N requirements, of the WFIRST IFS to capitalize on these systematic error reduction methods. b) Supernova extraction and host galaxy subtractions. The underlying light of the host galaxy must be subtracted from the supernova images making up the lightcurves. Using the IFS to provide the lightcurve points via spectrophotometry requires the subtraction of a reference spectrum of the galaxy taken after the supernova light has faded to a negligible level. We plan to apply the expertise obtained from the SNfactory to develop galaxy background procedures that minimize the systematic errors introduced by this step in the analysis. c) Instrument calibration and ground to space cross calibration. Calibrating the entire supernova sample will be a challenge as no standard stars exist that span the range of magnitudes and wavelengths relevant to the WFIRST survey. Linking the supernova measurements to the relatively brighter standards will require several links. WFIRST will produce the high redshift sample, but the nearby supernova to anchor the Hubble diagram will have to come from ground based observations. Developing algorithms to carry out the cross calibration of these two samples to the required one percent level will be an important goal of our proposal. An integral part of this calibration will be to remove all instrumental signatures and to develop unbiased measurement techniques starting at the pixel level. We then plan to pull the above studies together in a synthesis to produce a correlated error matrix. We plan to develop a Fisher Matrix based model to evaluate the correlated error matrix due to the various systematic errors discussed above. A realistic error model will allow us to carry out a more reliable estimates of the eventual errors on the measurement of the cosmological parameters, as well as serve as a means of optimizing and fine tuning the requirements for the instruments and survey strategies.

Advancing the research agenda for diagnostic error reduction.

PubMed

Zwaan, Laura; Schiff, Gordon D; Singh, Hardeep

2013-10-01

Diagnostic errors remain an underemphasised and understudied area of patient safety research. We briefly summarise the methods that have been used to conduct research on epidemiology, contributing factors and interventions related to diagnostic error and outline directions for future research. Research methods that have studied epidemiology of diagnostic error provide some estimate on diagnostic error rates. However, there appears to be a large variability in the reported rates due to the heterogeneity of definitions and study methods used. Thus, future methods should focus on obtaining more precise estimates in different settings of care. This would lay the foundation for measuring error rates over time to evaluate improvements. Research methods have studied contributing factors for diagnostic error in both naturalistic and experimental settings. Both approaches have revealed important and complementary information. Newer conceptual models from outside healthcare are needed to advance the depth and rigour of analysis of systems and cognitive insights of causes of error. While the literature has suggested many potentially fruitful interventions for reducing diagnostic errors, most have not been systematically evaluated and/or widely implemented in practice. Research is needed to study promising intervention areas such as enhanced patient involvement in diagnosis, improving diagnosis through the use of electronic tools and identification and reduction of specific diagnostic process 'pitfalls' (eg, failure to conduct appropriate diagnostic evaluation of a breast lump after a 'normal' mammogram). The last decade of research on diagnostic error has made promising steps and laid a foundation for more rigorous methods to advance the field.

77 FR 41699 - Transportation of Household Goods in Interstate Commerce; Consumer Protection Regulations...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-16

... due Revision due to agency Collection Old burden to error error (old-- error) IC1: ``Ready to Move... Revisions of Estimates of Annual Costs to Respondents Total cost Collection New cost Old cost reduction (new--old) IC1: ``Ready to Move?'' $288,000 $720,000 -$432,000 ``Rights & Responsibilities'' 3,264,000 8,160...

Assessing the accuracy and feasibility of a refractive error screening program conducted by school teachers in pre-primary and primary schools in Thailand.

PubMed

Teerawattananon, Kanlaya; Myint, Chaw-Yin; Wongkittirux, Kwanjai; Teerawattananon, Yot; Chinkulkitnivat, Bunyong; Orprayoon, Surapong; Kusakul, Suwat; Tengtrisorn, Supaporn; Jenchitr, Watanee

2014-01-01

As part of the development of a system for the screening of refractive error in Thai children, this study describes the accuracy and feasibility of establishing a program conducted by teachers. To assess the accuracy and feasibility of screening by teachers. A cross-sectional descriptive and analytical study was conducted in 17 schools in four provinces representing four geographic regions in Thailand. A two-staged cluster sampling was employed to compare the detection rate of refractive error among eligible students between trained teachers and health professionals. Serial focus group discussions were held for teachers and parents in order to understand their attitude towards refractive error screening at schools and the potential success factors and barriers. The detection rate of refractive error screening by teachers among pre-primary school children is relatively low (21%) for mild visual impairment but higher for moderate visual impairment (44%). The detection rate for primary school children is high for both levels of visual impairment (52% for mild and 74% for moderate). The focus group discussions reveal that both teachers and parents would benefit from further education regarding refractive errors and that the vast majority of teachers are willing to conduct a school-based screening program. Refractive error screening by health professionals in pre-primary and primary school children is not currently implemented in Thailand due to resource limitations. However, evidence suggests that a refractive error screening program conducted in schools by teachers in the country is reasonable and feasible because the detection and treatment of refractive error in very young generations is important and the screening program can be implemented and conducted with relatively low costs.

An evaluation of programmed treatment-integrity errors during discrete-trial instruction.

PubMed

Carroll, Regina A; Kodak, Tiffany; Fisher, Wayne W

2013-01-01

This study evaluated the effects of programmed treatment-integrity errors on skill acquisition for children with an autism spectrum disorder (ASD) during discrete-trial instruction (DTI). In Study 1, we identified common treatment-integrity errors that occur during academic instruction in schools. In Study 2, we simultaneously manipulated 3 integrity errors during DTI. In Study 3, we evaluated the effects of each of the 3 integrity errors separately on skill acquisition during DTI. Results showed that participants either demonstrated slower skill acquisition or did not acquire the target skills when instruction included treatment-integrity errors. © Society for the Experimental Analysis of Behavior.

Analysis of surface-water data network in Kansas for effectiveness in providing regional streamflow information; with a section on theory and application of generalized least squares

USGS Publications Warehouse

Medina, K.D.; Tasker, Gary D.

1987-01-01

This report documents the results of an analysis of the surface-water data network in Kansas for its effectiveness in providing regional streamflow information. The network was analyzed using generalized least squares regression. The correlation and time-sampling error of the streamflow characteristic are considered in the generalized least squares method. Unregulated medium-, low-, and high-flow characteristics were selected to be representative of the regional information that can be obtained from streamflow-gaging-station records for use in evaluating the effectiveness of continuing the present network stations, discontinuing some stations, and (or) adding new stations. The analysis used streamflow records for all currently operated stations that were not affected by regulation and for discontinued stations for which unregulated flow characteristics, as well as physical and climatic characteristics, were available. The State was divided into three network areas, western, northeastern, and southeastern Kansas, and analysis was made for the three streamflow characteristics in each area, using three planning horizons. The analysis showed that the maximum reduction of sampling mean-square error for each cost level could be obtained by adding new stations and discontinuing some current network stations. Large reductions in sampling mean-square error for low-flow information could be achieved in all three network areas, the reduction in western Kansas being the most dramatic. The addition of new stations would be most beneficial for mean-flow information in western Kansas. The reduction of sampling mean-square error for high-flow information would benefit most from the addition of new stations in western Kansas. Southeastern Kansas showed the smallest error reduction in high-flow information. A comparison among all three network areas indicated that funding resources could be most effectively used by discontinuing more stations in northeastern and southeastern Kansas and establishing more new stations in western Kansas.

Analysis of surface-water data network in Kansas for effectiveness in providing regional streamflow information

USGS Publications Warehouse

Medina, K.D.; Tasker, Gary D.

1985-01-01

The surface water data network in Kansas was analyzed using generalized least squares regression for its effectiveness in providing regional streamflow information. The correlation and time-sampling error of the streamflow characteristic are considered in the generalized least squares method. Unregulated medium-flow, low-flow and high-flow characteristics were selected to be representative of the regional information that can be obtained from streamflow gaging station records for use in evaluating the effectiveness of continuing the present network stations, discontinuing some stations; and/or adding new stations. The analysis used streamflow records for all currently operated stations that were not affected by regulation and discontinued stations for which unregulated flow characteristics , as well as physical and climatic characteristics, were available. The state was divided into three network areas, western, northeastern, and southeastern Kansas, and analysis was made for three streamflow characteristics in each area, using three planning horizons. The analysis showed that the maximum reduction of sampling mean square error for each cost level could be obtained by adding new stations and discontinuing some of the present network stations. Large reductions in sampling mean square error for low-flow information could be accomplished in all three network areas, with western Kansas having the most dramatic reduction. The addition of new stations would be most beneficial for man- flow information in western Kansas, and to lesser degrees in the other two areas. The reduction of sampling mean square error for high-flow information would benefit most from the addition of new stations in western Kansas, and the effect diminishes to lesser degrees in the other two areas. Southeastern Kansas showed the smallest error reduction in high-flow information. A comparison among all three network areas indicated that funding resources could be most effectively used by discontinuing more stations in northeastern and southeastern Kansas and establishing more new stations in western Kansas. (Author 's abstract)

Permanent-File-Validation Utility Computer Program

NASA Technical Reports Server (NTRS)

Derry, Stephen D.

1988-01-01

Errors in files detected and corrected during operation. Permanent File Validation (PFVAL) utility computer program provides CDC CYBER NOS sites with mechanism to verify integrity of permanent file base. Locates and identifies permanent file errors in Mass Storage Table (MST) and Track Reservation Table (TRT), in permanent file catalog entries (PFC's) in permit sectors, and in disk sector linkage. All detected errors written to listing file and system and job day files. Program operates by reading system tables , catalog track, permit sectors, and disk linkage bytes to vaidate expected and actual file linkages. Used extensively to identify and locate errors in permanent files and enable online correction, reducing computer-system downtime.

UCAC3: ASTROMETRIC REDUCTIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finch, Charlie T.; Zacharias, Norbert; Wycoff, Gary L., E-mail: finch@usno.navy.mi

2010-06-15

Presented here are the details of the astrometric reductions from the x, y data to mean right ascension (R.A.), declination (decl.) coordinates of the third U.S. Naval Observatory CCD Astrograph Catalog (UCAC3). For these new reductions we used over 216,000 CCD exposures. The Two-Micron All-Sky Survey (2MASS) data are used extensively to probe for coordinate and coma-like systematic errors in UCAC data mainly caused by the poor charge transfer efficiency of the 4K CCD. Errors up to about 200 mas have been corrected using complex look-up tables handling multiple dependences derived from the residuals. Similarly, field distortions and sub-pixel phasemore » errors have also been evaluated using the residuals with respect to 2MASS. The overall magnitude equation is derived from UCAC calibration field observations alone, independent of external catalogs. Systematic errors of positions at the UCAC observing epoch as presented in UCAC3 are better corrected than in the previous catalogs for most stars. The Tycho-2 catalog is used to obtain final positions on the International Celestial Reference Frame. Residuals of the Tycho-2 reference stars show a small magnitude equation (depending on declination zone) that might be inherent in the Tycho-2 catalog.« less

Fast online generalized multiscale finite element method using constraint energy minimization

NASA Astrophysics Data System (ADS)

Chung, Eric T.; Efendiev, Yalchin; Leung, Wing Tat

2018-02-01

Local multiscale methods often construct multiscale basis functions in the offline stage without taking into account input parameters, such as source terms, boundary conditions, and so on. These basis functions are then used in the online stage with a specific input parameter to solve the global problem at a reduced computational cost. Recently, online approaches have been introduced, where multiscale basis functions are adaptively constructed in some regions to reduce the error significantly. In multiscale methods, it is desired to have only 1-2 iterations to reduce the error to a desired threshold. Using Generalized Multiscale Finite Element Framework [10], it was shown that by choosing sufficient number of offline basis functions, the error reduction can be made independent of physical parameters, such as scales and contrast. In this paper, our goal is to improve this. Using our recently proposed approach [4] and special online basis construction in oversampled regions, we show that the error reduction can be made sufficiently large by appropriately selecting oversampling regions. Our numerical results show that one can achieve a three order of magnitude error reduction, which is better than our previous methods. We also develop an adaptive algorithm and enrich in selected regions with large residuals. In our adaptive method, we show that the convergence rate can be determined by a user-defined parameter and we confirm this by numerical simulations. The analysis of the method is presented.

Impact of Frequent Interruption on Nurses' Patient-Controlled Analgesia Programming Performance.

PubMed

Campoe, Kristi R; Giuliano, Karen K

2017-12-01

The purpose was to add to the body of knowledge regarding the impact of interruption on acute care nurses' cognitive workload, total task completion times, nurse frustration, and medication administration error while programming a patient-controlled analgesia (PCA) pump. Data support that the severity of medication administration error increases with the number of interruptions, which is especially critical during the administration of high-risk medications. Bar code technology, interruption-free zones, and medication safety vests have been shown to decrease administration-related errors. However, there are few published data regarding the impact of number of interruptions on nurses' clinical performance during PCA programming. Nine acute care nurses completed three PCA pump programming tasks in a simulation laboratory. Programming tasks were completed under three conditions where the number of interruptions varied between two, four, and six. Outcome measures included cognitive workload (six NASA Task Load Index [NASA-TLX] subscales), total task completion time (seconds), nurse frustration (NASA-TLX Subscale 6), and PCA medication administration error (incorrect final programming). Increases in the number of interruptions were associated with significant increases in total task completion time ( p = .003). We also found increases in nurses' cognitive workload, nurse frustration, and PCA pump programming errors, but these increases were not statistically significant. Complex technology use permeates the acute care nursing practice environment. These results add new knowledge on nurses' clinical performance during PCA pump programming and high-risk medication administration.

Comparing errors in ED computer-assisted vs conventional pediatric drug dosing and administration.

PubMed

Yamamoto, Loren; Kanemori, Joan

2010-06-01

Compared to fixed-dose single-vial drug administration in adults, pediatric drug dosing and administration requires a series of calculations, all of which are potentially error prone. The purpose of this study is to compare error rates and task completion times for common pediatric medication scenarios using computer program assistance vs conventional methods. Two versions of a 4-part paper-based test were developed. Each part consisted of a set of medication administration and/or dosing tasks. Emergency department and pediatric intensive care unit nurse volunteers completed these tasks using both methods (sequence assigned to start with a conventional or a computer-assisted approach). Completion times, errors, and the reason for the error were recorded. Thirty-eight nurses completed the study. Summing the completion of all 4 parts, the mean conventional total time was 1243 seconds vs the mean computer program total time of 879 seconds (P < .001). The conventional manual method had a mean of 1.8 errors vs the computer program with a mean of 0.7 errors (P < .001). Of the 97 total errors, 36 were due to misreading the drug concentration on the label, 34 were due to calculation errors, and 8 were due to misplaced decimals. Of the 36 label interpretation errors, 18 (50%) occurred with digoxin or insulin. Computerized assistance reduced errors and the time required for drug administration calculations. A pattern of errors emerged, noting that reading/interpreting certain drug labels were more error prone. Optimizing the layout of drug labels could reduce the error rate for error-prone labels. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Analytic score distributions for a spatially continuous tridirectional Monte Carol transport problem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Booth, T.E.

1996-01-01

The interpretation of the statistical error estimates produced by Monte Carlo transport codes is still somewhat of an art. Empirically, there are variance reduction techniques whose error estimates are almost always reliable, and there are variance reduction techniques whose error estimates are often unreliable. Unreliable error estimates usually result from inadequate large-score sampling from the score distribution`s tail. Statisticians believe that more accurate confidence interval statements are possible if the general nature of the score distribution can be characterized. Here, the analytic score distribution for the exponential transform applied to a simple, spatially continuous Monte Carlo transport problem is provided.more » Anisotropic scattering and implicit capture are included in the theory. In large part, the analytic score distributions that are derived provide the basis for the ten new statistical quality checks in MCNP.« less

Efficient detection of dangling pointer error for C/C++ programs

NASA Astrophysics Data System (ADS)

Zhang, Wenzhe

2017-08-01

Dangling pointer error is pervasive in C/C++ programs and it is very hard to detect. This paper introduces an efficient detector to detect dangling pointer error in C/C++ programs. By selectively leave some memory accesses unmonitored, our method could reduce the memory monitoring overhead and thus achieves better performance over previous methods. Experiments show that our method could achieve an average speed up of 9% over previous compiler instrumentation based method and more than 50% over previous page protection based method.

Magnitude error bounds for sampled-data frequency response obtained from the truncation of an infinite series, and compensator improvement program

NASA Technical Reports Server (NTRS)

Mitchell, J. R.

1972-01-01

The frequency response method of analyzing control system performance is discussed, and the difficulty of obtaining the sampled frequency response of the continuous system is considered. An upper bound magnitude error equation is obtained which yields reasonable estimates of the actual error. Finalization of the compensator improvement program is also reported, and the program was used to design compensators for Saturn 5/S1-C dry workshop and Saturn 5/S1-C Skylab.

Automated Hypothesis Tests and Standard Errors for Nonstandard Problems with Description of Computer Package: A Draft.

ERIC Educational Resources Information Center

Lord, Frederic M.; Stocking, Martha

A general Computer program is described that will compute asymptotic standard errors and carry out significance tests for an endless variety of (standard and) nonstandard large-sample statistical problems, without requiring the statistician to derive asymptotic standard error formulas. The program assumes that the observations have a multinormal…

Risk management systems for health care and safety development on transplantation: a review and a proposal.

PubMed

Pretagostini, R; Gabbrielli, F; Fiaschetti, P; Oliveti, A; Cenci, S; Peritore, D; Stabile, D

2010-05-01

Starting from the report on medical errors published in 1999 by the US Institute of Medicine, a number of different approaches to risk management have been developed for maximum risk reduction in health care activities. The health care authorities in many countries have focused attention on patient safety, employing action research programs that are based on quite different principles. We performed a systematic Medline research of the literature since 1999. The following key words were used, also combining boolean operators and medical subheading terms: "adverse event," "risk management," "error," and "governance." Studies published in the last 5 years were particularly classified in various groups: risk management in health care systems; safety in specific hospital activities; and health care institutions' official documents. Methods of action researches have been analysed and their characteristics compared. Their suitability for safety development in donation, retrieval, and transplantation processes were discussed in the reality of the Italian transplant network. Some action researches and studies were dedicated to entire national healthcare systems, whereas others focused on specific risks. Many research programs have undergone critical review in the literature. Retrospective analysis has centered on so-called sentinel events to particularly analyze only a minor portion of the organizational phenomena, which can be the origin of an adverse event, an incident, or an error. Sentinel events give useful information if they are studied in highly engineered and standardized organizations like laboratories or tissue establishments, but they show several limits in the analysis of organ donation, retrieval, and transplantation processes, which are characterized by prevailing human factors, with high intrinsic risk and variability. Thus, they are poorly effective to deliver sure elements to base safety management improvement programs, especially regarding multidisciplinary systems with high complexity. In organ transplantation, the possibility to increase safety seems greater using proactive research, mainly centred on organizational processes together with retrospective analyses but not limited to sentinel event reports. Copyright (c) 2010. Published by Elsevier Inc.

Space Trajectory Error Analysis Program (STEAP) for halo orbit missions. Volume 1: Analytic and user's manual

NASA Technical Reports Server (NTRS)

Byrnes, D. V.; Carney, P. C.; Underwood, J. W.; Vogt, E. D.

1974-01-01

Development, test, conversion, and documentation of computer software for the mission analysis of missions to halo orbits about libration points in the earth-sun system is reported. The software consisting of two programs called NOMNAL and ERRAN is part of the Space Trajectories Error Analysis Programs (STEAP). The program NOMNAL targets a transfer trajectory from Earth on a given launch date to a specified halo orbit on a required arrival date. Either impulsive or finite thrust insertion maneuvers into halo orbit are permitted by the program. The transfer trajectory is consistent with a realistic launch profile input by the user. The second program ERRAN conducts error analyses of the targeted transfer trajectory. Measurements including range, doppler, star-planet angles, and apparent planet diameter are processed in a Kalman-Schmidt filter to determine the trajectory knowledge uncertainty. Execution errors at injection, midcourse correction and orbit insertion maneuvers are analyzed along with the navigation uncertainty to determine trajectory control uncertainties and fuel-sizing requirements. The program is also capable of generalized covariance analyses.

The effectiveness of the error reporting promoting program on the nursing error incidence rate in Korean operating rooms.

PubMed

Kim, Myoung-Soo; Kim, Jung-Soon; Jung, In Sook; Kim, Young Hae; Kim, Ho Jung

2007-03-01

The purpose of this study was to develop and evaluate an error reporting promoting program(ERPP) to systematically reduce the incidence rate of nursing errors in operating room. A non-equivalent control group non-synchronized design was used. Twenty-six operating room nurses who were in one university hospital in Busan participated in this study. They were stratified into four groups according to their operating room experience and were allocated to the experimental and control groups using a matching method. Mann-Whitney U Test was used to analyze the differences pre and post incidence rates of nursing errors between the two groups. The incidence rate of nursing errors decreased significantly in the experimental group compared to the pre-test score from 28.4% to 15.7%. The incidence rate by domains, it decreased significantly in the 3 domains-"compliance of aseptic technique", "management of document", "environmental management" in the experimental group while it decreased in the control group which was applied ordinary error-reporting method. Error-reporting system can make possible to hold the errors in common and to learn from them. ERPP was effective to reduce the errors of recognition-related nursing activities. For the wake of more effective error-prevention, we will be better to apply effort of risk management along the whole health care system with this program.

Workplace-based participatory approach to weight loss for correctional employees.

PubMed

Ferraro, Lindsay; Faghri, Pouran D; Henning, Robert; Cherniack, Martin

2013-02-01

To evaluate the effectiveness of a participatory approach using an employee design team for a 12-week weight-loss program with an 8-week follow-up. Twenty-four employees with mean [standard error (SE)] for weight 233.24 lb [8.16], body mass index 33.29 kg/cm [0.82], and age 42.7 years [1.5] participated in the study, among whom 75% were men and 25% women. Significant reductions in weight, body mass index, and waist circumference (among men) were observed before and after intervention (P < 0.05). About 73% and 68% of the variation in weight change (P < 0.01) and waist circumference (P < 0.01), respectively, were explained by Nutrition Knowledge and Exercise Confidence scores after controlling for gender and age. A participatory program with employee involvement resulted in positive outcomes. Increasing participants' knowledge and providing skills to manage their weight seem to change their attitudes, resulting in better outcomes.

Adaptive reduction of constitutive model-form error using a posteriori error estimation techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bishop, Joseph E.; Brown, Judith Alice

In engineering practice, models are typically kept as simple as possible for ease of setup and use, computational efficiency, maintenance, and overall reduced complexity to achieve robustness. In solid mechanics, a simple and efficient constitutive model may be favored over one that is more predictive, but is difficult to parameterize, is computationally expensive, or is simply not available within a simulation tool. In order to quantify the modeling error due to the choice of a relatively simple and less predictive constitutive model, we adopt the use of a posteriori model-form error-estimation techniques. Based on local error indicators in the energymore » norm, an algorithm is developed for reducing the modeling error by spatially adapting the material parameters in the simpler constitutive model. The resulting material parameters are not material properties per se, but depend on the given boundary-value problem. As a first step to the more general nonlinear case, we focus here on linear elasticity in which the “complex” constitutive model is general anisotropic elasticity and the chosen simpler model is isotropic elasticity. As a result, the algorithm for adaptive error reduction is demonstrated using two examples: (1) A transversely-isotropic plate with hole subjected to tension, and (2) a transversely-isotropic tube with two side holes subjected to torsion.« less

Adaptive reduction of constitutive model-form error using a posteriori error estimation techniques

DOE PAGES

Bishop, Joseph E.; Brown, Judith Alice

2018-06-15

In engineering practice, models are typically kept as simple as possible for ease of setup and use, computational efficiency, maintenance, and overall reduced complexity to achieve robustness. In solid mechanics, a simple and efficient constitutive model may be favored over one that is more predictive, but is difficult to parameterize, is computationally expensive, or is simply not available within a simulation tool. In order to quantify the modeling error due to the choice of a relatively simple and less predictive constitutive model, we adopt the use of a posteriori model-form error-estimation techniques. Based on local error indicators in the energymore » norm, an algorithm is developed for reducing the modeling error by spatially adapting the material parameters in the simpler constitutive model. The resulting material parameters are not material properties per se, but depend on the given boundary-value problem. As a first step to the more general nonlinear case, we focus here on linear elasticity in which the “complex” constitutive model is general anisotropic elasticity and the chosen simpler model is isotropic elasticity. As a result, the algorithm for adaptive error reduction is demonstrated using two examples: (1) A transversely-isotropic plate with hole subjected to tension, and (2) a transversely-isotropic tube with two side holes subjected to torsion.« less

Reduction of Orifice-Induced Pressure Errors

NASA Technical Reports Server (NTRS)

Plentovich, Elizabeth B.; Gloss, Blair B.; Eves, John W.; Stack, John P.

1987-01-01

Use of porous-plug orifice reduces or eliminates errors, induced by orifice itself, in measuring static pressure on airfoil surface in wind-tunnel experiments. Piece of sintered metal press-fitted into static-pressure orifice so it matches surface contour of model. Porous material reduces orifice-induced pressure error associated with conventional orifice of same or smaller diameter. Also reduces or eliminates additional errors in pressure measurement caused by orifice imperfections. Provides more accurate measurements in regions with very thin boundary layers.

JPL-ANTOPT antenna structure optimization program

NASA Technical Reports Server (NTRS)

Strain, D. M.

1994-01-01

New antenna path-length error and pointing-error structure optimization codes were recently added to the MSC/NASTRAN structural analysis computer program. Path-length and pointing errors are important measured of structure-related antenna performance. The path-length and pointing errors are treated as scalar displacements for statics loading cases. These scalar displacements can be subject to constraint during the optimization process. Path-length and pointing-error calculations supplement the other optimization and sensitivity capabilities of NASTRAN. The analysis and design functions were implemented as 'DMAP ALTERs' to the Design Optimization (SOL 200) Solution Sequence of MSC-NASTRAN, Version 67.5.

Symbolic Analysis of Concurrent Programs with Polymorphism

NASA Technical Reports Server (NTRS)

Rungta, Neha Shyam

2010-01-01

The current trend of multi-core and multi-processor computing is causing a paradigm shift from inherently sequential to highly concurrent and parallel applications. Certain thread interleavings, data input values, or combinations of both often cause errors in the system. Systematic verification techniques such as explicit state model checking and symbolic execution are extensively used to detect errors in such systems [7, 9]. Explicit state model checking enumerates possible thread schedules and input data values of a program in order to check for errors [3, 9]. To partially mitigate the state space explosion from data input values, symbolic execution techniques substitute data input values with symbolic values [5, 7, 6]. Explicit state model checking and symbolic execution techniques used in conjunction with exhaustive search techniques such as depth-first search are unable to detect errors in medium to large-sized concurrent programs because the number of behaviors caused by data and thread non-determinism is extremely large. We present an overview of abstraction-guided symbolic execution for concurrent programs that detects errors manifested by a combination of thread schedules and data values [8]. The technique generates a set of key program locations relevant in testing the reachability of the target locations. The symbolic execution is then guided along these locations in an attempt to generate a feasible execution path to the error state. This allows the execution to focus in parts of the behavior space more likely to contain an error.

Bias error reduction using ratios to baseline experiments. Heat transfer case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakroun, W.; Taylor, R.P.; Coleman, H.W.

1993-10-01

Employing a set of experiments devoted to examining the effect of surface finish (riblets) on convective heat transfer as an example, this technical note seeks to explore the notion that precision uncertainties in experiments can be reduced by repeated trials and averaging. This scheme for bias error reduction can give considerable advantage when parametric effects are investigated experimentally. When the results of an experiment are presented as a ratio with the baseline results, a large reduction in the overall uncertainty can be achieved when all the bias limits in the variables of the experimental result are fully correlated with thosemore » of the baseline case. 4 refs.« less

Effects of motion base and g-seat cueing of simulator pilot performance

NASA Technical Reports Server (NTRS)

Ashworth, B. R.; Mckissick, B. T.; Parrish, R. V.

1984-01-01

In order to measure and analyze the effects of a motion plus g-seat cueing system, a manned-flight-simulation experiment was conducted utilizing a pursuit tracking task and an F-16 simulation model in the NASA Langley visual/motion simulator. This experiment provided the information necessary to determine whether motion and g-seat cues have an additive effect on the performance of this task. With respect to the lateral tracking error and roll-control stick force, the answer is affirmative. It is shown that presenting the two cues simultaneously caused significant reductions in lateral tracking error and that using the g-seat and motion base separately provided essentially equal reductions in the pilot's lateral tracking error.

Student Performance in Computer-Assisted Instruction in Programming.

ERIC Educational Resources Information Center

Friend, Jamesine E.; And Others

A computer-assisted instructional system to teach college students the computer language, AID (Algebraic Interpretive Dialogue), two control programs, and data collected by the two control programs are described. It was found that although first response errors were often those of AID syntax, such errors were easily corrected. Secondly, while…

Computer Programs for the Semantic Differential: Further Modifications.

ERIC Educational Resources Information Center

Lawson, Edwin D.; And Others

The original nine programs for semantic differential analysis have been condensed into three programs which have been further refined and augmented. They yield: (1) means, standard deviations, and standard errors for each subscale on each concept; (2) Evaluation, Potency, and Activity (EPA) means, standard deviations, and standard errors; (3)…

76 FR 41178 - Medicare Program; Proposed Changes to the Hospital Inpatient Prospective Payment Systems for...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-13

... Insurance; and Program No. 93.774, Medicare-- Supplementary Medical Insurance Program) Dated: July 7, 2011...), HHS. ACTION: Correction of proposed rule. SUMMARY: This document corrects technical errors that... explanation of publishing such Tables on the Internet), reflect an error in the calculation of the...

75 FR 30756 - Medicare Program; Supplemental Proposed Changes to the Hospital Inpatient Prospective Payment...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-02

.... 93.773, Medicare--Hospital Insurance; and Program No. 93.774, Medicare-- Supplementary Medical... technical errors that appeared in the supplementary proposed rule entitled ``Medicare Program; Supplemental... Doc. 2010-12567 filed May 21, 2010, there are technical and typographical errors that are identified...

SpecOp: Optimal Extraction Software for Integral Field Unit Spectrographs

NASA Astrophysics Data System (ADS)

McCarron, Adam; Ciardullo, Robin; Eracleous, Michael

2018-01-01

The Hobby-Eberly Telescope’s new low resolution integral field spectrographs, LRS2-B and LRS2-R, each cover a 12”x6” area on the sky with 280 fibers and generate spectra with resolutions between R=1100 and R=1900. To extract 1-D spectra from the instrument’s 3D data cubes, a program is needed that is flexible enough to work for a wide variety of targets, including continuum point sources, emission line sources, and compact sources embedded in complex backgrounds. We therefore introduce SpecOp, a user-friendly python program for optimally extracting spectra from integral-field unit spectrographs. As input, SpecOp takes a sky-subtracted data cube consisting of images at each wavelength increment set by the instrument’s spectral resolution, and an error file for each count measurement. All of these files are generated by the current LRS2 reduction pipeline. The program then collapses the cube in the image plane using the optimal extraction algorithm detailed by Keith Horne (1986). The various user-selected options include the fraction of the total signal enclosed in a contour-defined region, the wavelength range to analyze, and the precision of the spatial profile calculation. SpecOp can output the weighted counts and errors at each wavelength in various table formats using python’s astropy package. We outline the algorithm used for extraction and explain how the software can be used to easily obtain high-quality 1-D spectra. We demonstrate the utility of the program by applying it to spectra of a variety of quasars and AGNs. In some of these targets, we extract the spectrum of a nuclear point source that is superposed on a spatially extended galaxy.

Sensory training with vibration-induced kinesthetic illusions improves proprioceptive integration in patients with Parkinson's disease.

PubMed

Ribot-Ciscar, Edith; Aimonetti, Jean-Marc; Azulay, Jean-Philippe

2017-12-15

The present study investigates whether proprioceptive training, based on kinesthetic illusions, can help in re-educating the processing of muscle proprioceptive input, which is impaired in patients with Parkinson's disease (PD). The processing of proprioceptive input before and after training was evaluated by determining the error in the amplitude of voluntary dorsiflexion ankle movement (20°), induced by applying a vibration on the tendon of the gastrocnemius-soleus muscle (a vibration-induced movement error). The training consisted of the subjects focusing their attention upon a series of illusory movements of the ankle. Eleven PD patients and eleven age-matched control subjects were tested. Before training, vibration reduced dorsiflexion amplitude in controls by 4.3° (P<0.001); conversely, vibration was inefficient in PD's movement amplitude (reduction of 2.1°, P=0.20). After training, vibration significantly reduced the estimated movement amplitude in PD patients by 5.3° (P=0.01). This re-emergence of a vibration-induced error leads us to conclude that proprioceptive training, based on kinesthetic illusions, is a simple means for re-educating the processing of muscle proprioceptive input in PD patients. Such complementary training should be included in rehabilitation programs that presently focus on improving balance and motor performance. Copyright © 2017 Elsevier B.V. All rights reserved.

Improving treatment plan evaluation with automation.

PubMed

Covington, Elizabeth L; Chen, Xiaoping; Younge, Kelly C; Lee, Choonik; Matuszak, Martha M; Kessler, Marc L; Keranen, Wayne; Acosta, Eduardo; Dougherty, Ashley M; Filpansick, Stephanie E; Moran, Jean M

2016-11-08

The goal of this work is to evaluate the effectiveness of Plan-Checker Tool (PCT) which was created to improve first-time plan quality, reduce patient delays, increase the efficiency of our electronic workflow, and standardize and automate the phys-ics plan review in the treatment planning system (TPS). PCT uses an application programming interface to check and compare data from the TPS and treatment management system (TMS). PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user as part of a plan readiness check for treatment. Prior to and during PCT development, errors identified during the physics review and causes of patient treatment start delays were tracked to prioritize which checks should be automated. Nineteen of 33checklist items were automated, with data extracted with PCT. There was a 60% reduction in the number of patient delays in the six months after PCT release. PCT was suc-cessfully implemented for use on all external beam treatment plans in our clinic. While the number of errors found during the physics check did not decrease, automation of checks increased visibility of errors during the physics check, which led to decreased patient delays. The methods used here can be applied to any TMS and TPS that allows queries of the database. © 2016 The Authors.

40 CFR 96.256 - Account error.

Code of Federal Regulations, 2010 CFR

2010-07-01

... TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS FOR STATE IMPLEMENTATION PLANS CAIR SO2 Allowance... her own motion, correct any error in any CAIR SO2 Allowance Tracking System account. Within 10...

Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niemeyer, Kyle E.; Sung, Chih-Jen

Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, suchmore » as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.« less

Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

DOE PAGES

Niemeyer, Kyle E.; Sung, Chih-Jen

2014-11-01

Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, suchmore » as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.« less

Analyzing human errors in flight mission operations

NASA Technical Reports Server (NTRS)

Bruno, Kristin J.; Welz, Linda L.; Barnes, G. Michael; Sherif, Josef

1993-01-01

A long-term program is in progress at JPL to reduce cost and risk of flight mission operations through a defect prevention/error management program. The main thrust of this program is to create an environment in which the performance of the total system, both the human operator and the computer system, is optimized. To this end, 1580 Incident Surprise Anomaly reports (ISA's) from 1977-1991 were analyzed from the Voyager and Magellan projects. A Pareto analysis revealed that 38 percent of the errors were classified as human errors. A preliminary cluster analysis based on the Magellan human errors (204 ISA's) is presented here. The resulting clusters described the underlying relationships among the ISA's. Initial models of human error in flight mission operations are presented. Next, the Voyager ISA's will be scored and included in the analysis. Eventually, these relationships will be used to derive a theoretically motivated and empirically validated model of human error in flight mission operations. Ultimately, this analysis will be used to make continuous process improvements continuous process improvements to end-user applications and training requirements. This Total Quality Management approach will enable the management and prevention of errors in the future.

Flight Test Results of an Angle of Attack and Angle of Sideslip Calibration Method Using Output-Error Optimization

NASA Technical Reports Server (NTRS)

Siu, Marie-Michele; Martos, Borja; Foster, John V.

2013-01-01

As part of a joint partnership between the NASA Aviation Safety Program (AvSP) and the University of Tennessee Space Institute (UTSI), research on advanced air data calibration methods has been in progress. This research was initiated to expand a novel pitot-static calibration method that was developed to allow rapid in-flight calibration for the NASA Airborne Subscale Transport Aircraft Research (AirSTAR) facility. This approach uses Global Positioning System (GPS) technology coupled with modern system identification methods that rapidly computes optimal pressure error models over a range of airspeed with defined confidence bounds. Subscale flight tests demonstrated small 2-s error bounds with significant reduction in test time compared to other methods. Recent UTSI full scale flight tests have shown airspeed calibrations with the same accuracy or better as the Federal Aviation Administration (FAA) accepted GPS 'four-leg' method in a smaller test area and in less time. The current research was motivated by the desire to extend this method for inflight calibration of angle of attack (AOA) and angle of sideslip (AOS) flow vanes. An instrumented Piper Saratoga research aircraft from the UTSI was used to collect the flight test data and evaluate flight test maneuvers. Results showed that the output-error approach produces good results for flow vane calibration. In addition, maneuvers for pitot-static and flow vane calibration can be integrated to enable simultaneous and efficient testing of each system.

Stimulus Equalization: Temporary Reduction of Stimulus Complexity to Facilitate Discrimination Learning.

ERIC Educational Resources Information Center

Hoko, J. Aaron; LeBlanc, Judith M.

1988-01-01

Because disabled learners may profit from procedures using gradual stimulus change, this study utilized a microcomputer to investigate the effectiveness of stimulus equalization, an error reduction procedure involving an abrupt but temporary reduction of dimensional complexity. The procedure was found to be generally effective and implications for…

Prevalence of uncorrected refractive errors among school-age children in the School District of Philadelphia.

PubMed

Mayro, Eileen L; Hark, Lisa A; Shiuey, Eric; Pond, Michael; Siam, Linda; Hill-Bennett, Tamara; Tran, Judie; Khanna, Nitasha; Silverstein, Marlee; Donaghy, James; Zhan, Tingting; Murchison, Ann P; Levin, Alex V

2018-06-01

To determine the prevalence and severity of uncorrected refractive errors in school-age children attending Philadelphia public schools. The Wills Eye Vision Screening Program for Children is a community-based pediatric vision screening program designed to detect and correct refractive errors and refer those with nonrefractive eye diseases for examination by a pediatric ophthalmologist. Between January 2014 and June 2016 the program screened 18,974 children in grades K-5 in Philadelphia public schools. Children who failed the vision screening were further examined by an on-site ophthalmologist or optometrist; children whose decreased visual acuity was not amenable to spectacle correction were referred to a pediatric ophthalmologist. Of the 18,974 children screened, 2,492 (13.1%) exhibited uncorrected refractive errors: 1,776 (9.4%) children had myopia, 459 (2.4%) had hyperopia, 1,484 (7.8%) had astigmatism, and 846 (4.5%) had anisometropia. Of the 2,492 with uncorrected refractive error, 368 children (14.8%) had more than one refractive error diagnosis. In stratifying refractive error diagnoses by severity, mild myopia (spherical equivalent of -0.50 D to < -3.00 D) was the most common diagnosis, present in 1,573 (8.3%) children. In this urban population 13.1% of school-age children exhibited uncorrected refractive errors. Blurred vision may create challenges for students in the classroom; school-based vision screening programs can provide an avenue to identify and correct refractive errors. Copyright © 2018 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Chapter 11: Sample Design Cross-Cutting Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurnik, Charles W; Khawaja, M. Sami; Rushton, Josh

Evaluating an energy efficiency program requires assessing the total energy and demand saved through all of the energy efficiency measures provided by the program. For large programs, the direct assessment of savings for each participant would be cost-prohibitive. Even if a program is small enough that a full census could be managed, such an undertaking would almost always be an inefficient use of evaluation resources. The bulk of this chapter describes methods for minimizing and quantifying sampling error. Measurement error and regression error are discussed in various contexts in other chapters.

[Relations between health information systems and patient safety].

PubMed

Nøhr, Christian

2012-11-05

Health information systems have the potential to reduce medical errors, and indeed many studies have shown a significant reduction. However, if the systems are not designed and implemented properly, there is evidence that suggest that new types of errors will arise--i.e., technology-induced errors. Health information systems will need to undergo a more rigorous evaluation. Usability evaluation and simulation test with humans in the loop can help to detect and prevent technology-induced errors before they are deployed in real health-care settings.

Flight instrumentation specification for parameter identification: Program user's guide. [instrument errors/error analysis

NASA Technical Reports Server (NTRS)

Mohr, R. L.

1975-01-01

A set of four digital computer programs is presented which can be used to investigate the effects of instrumentation errors on the accuracy of aircraft and helicopter stability-and-control derivatives identified from flight test data. The programs assume that the differential equations of motion are linear and consist of small perturbations about a quasi-steady flight condition. It is also assumed that a Newton-Raphson optimization technique is used for identifying the estimates of the parameters. Flow charts and printouts are included.

Medical Errors Reduction Initiative

DTIC Science & Technology

2009-03-01

enough data was collected to have any statistical significance or determine impact on latent error in the process of blood transfusion. Bedside...of adverse drug events. JAMA 1995; 274: 35-43 . Leape, L.L., Brennan, T .A., & Laird, N .M. ( 1991) The nature of adverse events in hospitalized...Background Medical errors are a significant cause of morbidity and mortality among hospitalized patients (Kohn, Corrigan and Donaldson, 2000; Leape, Brennan

An Automated Program Testing Methodology and its Implementation.

DTIC Science & Technology

1980-01-01

correctly on its input data; the number of for each software system. asse rtions violated defines an "error function"Itiimoan tocos ecsswhh over the Input...space of the program. ThisItiimoan tocos tecse whh remove@ the need to examine a program’s output uncover errors early in the development cycle, in

75 FR 70013 - Medicare Program; Inpatient Rehabilitation Facility Prospective Payment System for Federal Fiscal...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-16

... Insurance; and Program No. 93.774, Medicare-- Supplementary Medical Insurance Program) Dated: November 9...: Correction notice. SUMMARY: This document corrects a technical error that appeared in the notice published in... of July 22, 2010 (75 FR 42836), there was a technical error that we are identifying and correcting in...

76 FR 34633 - Medicare Program; Proposed Changes to the Hospital Inpatient Prospective Payment Systems for...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-14

....773, Medicare--Hospital Insurance; and Program No. 93.774, Medicare-- Supplementary Medical Insurance... errors in the proposed rule entitled ``Medicare Program; Proposed Changes to the Hospital Inpatient...-9644 of May 5, 2011 (76 FR 25788), there were a number of technical and typographical errors that are...

Automatic Estimation of Verified Floating-Point Round-Off Errors via Static Analysis

NASA Technical Reports Server (NTRS)

Moscato, Mariano; Titolo, Laura; Dutle, Aaron; Munoz, Cesar A.

2017-01-01

This paper introduces a static analysis technique for computing formally verified round-off error bounds of floating-point functional expressions. The technique is based on a denotational semantics that computes a symbolic estimation of floating-point round-o errors along with a proof certificate that ensures its correctness. The symbolic estimation can be evaluated on concrete inputs using rigorous enclosure methods to produce formally verified numerical error bounds. The proposed technique is implemented in the prototype research tool PRECiSA (Program Round-o Error Certifier via Static Analysis) and used in the verification of floating-point programs of interest to NASA.

Effect of bar-code technology on the safety of medication administration.

PubMed

Poon, Eric G; Keohane, Carol A; Yoon, Catherine S; Ditmore, Matthew; Bane, Anne; Levtzion-Korach, Osnat; Moniz, Thomas; Rothschild, Jeffrey M; Kachalia, Allen B; Hayes, Judy; Churchill, William W; Lipsitz, Stuart; Whittemore, Anthony D; Bates, David W; Gandhi, Tejal K

2010-05-06

Serious medication errors are common in hospitals and often occur during order transcription or administration of medication. To help prevent such errors, technology has been developed to verify medications by incorporating bar-code verification technology within an electronic medication-administration system (bar-code eMAR). We conducted a before-and-after, quasi-experimental study in an academic medical center that was implementing the bar-code eMAR. We assessed rates of errors in order transcription and medication administration on units before and after implementation of the bar-code eMAR. Errors that involved early or late administration of medications were classified as timing errors and all others as nontiming errors. Two clinicians reviewed the errors to determine their potential to harm patients and classified those that could be harmful as potential adverse drug events. We observed 14,041 medication administrations and reviewed 3082 order transcriptions. Observers noted 776 nontiming errors in medication administration on units that did not use the bar-code eMAR (an 11.5% error rate) versus 495 such errors on units that did use it (a 6.8% error rate)--a 41.4% relative reduction in errors (P<0.001). The rate of potential adverse drug events (other than those associated with timing errors) fell from 3.1% without the use of the bar-code eMAR to 1.6% with its use, representing a 50.8% relative reduction (P<0.001). The rate of timing errors in medication administration fell by 27.3% (P<0.001), but the rate of potential adverse drug events associated with timing errors did not change significantly. Transcription errors occurred at a rate of 6.1% on units that did not use the bar-code eMAR but were completely eliminated on units that did use it. Use of the bar-code eMAR substantially reduced the rate of errors in order transcription and in medication administration as well as potential adverse drug events, although it did not eliminate such errors. Our data show that the bar-code eMAR is an important intervention to improve medication safety. (ClinicalTrials.gov number, NCT00243373.) 2010 Massachusetts Medical Society

Monitoring robot actions for error detection and recovery

NASA Technical Reports Server (NTRS)

Gini, M.; Smith, R.

1987-01-01

Reliability is a serious problem in computer controlled robot systems. Although robots serve successfully in relatively simple applications such as painting and spot welding, their potential in areas such as automated assembly is hampered by programming problems. A program for assembling parts may be logically correct, execute correctly on a simulator, and even execute correctly on a robot most of the time, yet still fail unexpectedly in the face of real world uncertainties. Recovery from such errors is far more complicated than recovery from simple controller errors, since even expected errors can often manifest themselves in unexpected ways. Here, a novel approach is presented for improving robot reliability. Instead of anticipating errors, researchers use knowledge-based programming techniques so that the robot can autonomously exploit knowledge about its task and environment to detect and recover from failures. They describe preliminary experiment of a system that they designed and constructed.

Single Event Upset Analysis: On-orbit performance of the Alpha Magnetic Spectrometer Digital Signal Processor Memory aboard the International Space Station

NASA Astrophysics Data System (ADS)

Li, Jiaqiang; Choutko, Vitaly; Xiao, Liyi

2018-03-01

Based on the collection of error data from the Alpha Magnetic Spectrometer (AMS) Digital Signal Processors (DSP), on-orbit Single Event Upsets (SEUs) of the DSP program memory are analyzed. The daily error distribution and time intervals between errors are calculated to evaluate the reliability of the system. The particle density distribution of International Space Station (ISS) orbit is presented and the effects from the South Atlantic Anomaly (SAA) and the geomagnetic poles are analyzed. The impact of solar events on the DSP program memory is carried out combining data analysis and Monte Carlo simulation (MC). From the analysis and simulation results, it is concluded that the area corresponding to the SAA is the main source of errors on the ISS orbit. Solar events can also cause errors on DSP program memory, but the effect depends on the on-orbit particle density.

40 CFR 97.256 - Account error.

Code of Federal Regulations, 2010 CFR

2010-07-01

... BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING PROGRAMS CAIR SO2 Allowance Tracking System § 97.256... any error in any CAIR SO2 Allowance Tracking System account. Within 10 business days of making such...

Explore Full Range of QSO/AGN Properties

NASA Technical Reports Server (NTRS)

Oliversen, Ronald (Technical Monitor); Wilkes, Belinda

2005-01-01

The goal of the proposal is to perform ISO spectroscopic studies, including data analysis and modeling, of star formation regions using an ensemble of archival space-based data from the Infrared Space Observatory s Long Wavelength Spectrometer and Short Wavelength Spectrometer, but including as well some other spectroscopic databases. Four kinds of regions are considered in the studies: (1) disks around more evolved objects; (2) young, low or high mass pre-main sequence stars in star formation regions; (3) star formation in external, bright IR galaxies; and (4) the galactic center. One prime focus of the program is the OH lines in the far infrared. The program had the following goals: 1) Refine the data analysis of IS0 observations to obtain deeper and better SNR results on selected sources. The IS0 data itself underwent "pipeline 10" reductions in early 2001, and additional "hands-on data reduction packages" were supplied by the IS0 teams in 2001. The Fabry-Perot database is particularly sensitive to noise and slight calibration errors. 2) Model the atomic and molecular line shapes, in particular the OH lines, using revised monte- carlo techniques developed by the SWAS team at the Center for Astrophysics; 3) Attend scientific meetings and workshops; 4) Do E&PO activities related to infrared astrophysics and/or spectroscopy.

The positive financial impact of using an Intensive Care Information System in a tertiary Intensive Care Unit.

PubMed

Levesque, Eric; Hoti, Emir; de La Serna, Sofia; Habouchi, Houssam; Ichai, Philippe; Saliba, Faouzi; Samuel, Didier; Azoulay, Daniel

2013-03-01

In the French healthcare system, the intensive care budget allocated is directly dependent on the activity level of the center. To evaluate this activity level, it is necessary to code the medical diagnoses and procedures performed on Intensive Care Unit (ICU) patients. The aim of this study was to evaluate the effects of using an Intensive Care Information System (ICIS) on the incidence of coding errors and its impact on the ICU budget allocated. Since 2005, the documentation on and monitoring of every patient admitted to our ICU has been carried out using an ICIS. However, the coding process was performed manually until 2008. This study focused on two periods: the period of manual coding (year 2007) and the period of computerized coding (year 2008) which covered a total of 1403 ICU patients. The time spent on the coding process, the rate of coding errors (defined as patients missed/not coded or wrongly identified as undergoing major procedure/s) and the financial impact were evaluated for these two periods. With computerized coding, the time per admission decreased significantly (from 6.8 ± 2.8 min in 2007 to 3.6 ± 1.9 min in 2008, p<0.001). Similarly, a reduction in coding errors was observed (7.9% vs. 2.2%, p<0.001). This decrease in coding errors resulted in a reduced difference between the potential and real ICU financial supplements obtained in the respective years (€194,139 loss in 2007 vs. a €1628 loss in 2008). Using specific computer programs improves the intensive process of manual coding by shortening the time required as well as reducing errors, which in turn positively impacts the ICU budget allocation. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Using failure mode and effects analysis to plan implementation of smart i.v. pump technology.

PubMed

Wetterneck, Tosha B; Skibinski, Kathleen A; Roberts, Tanita L; Kleppin, Susan M; Schroeder, Mark E; Enloe, Myra; Rough, Steven S; Hundt, Ann Schoofs; Carayon, Pascale

2006-08-15

Failure mode and effects analysis (FMEA) was used to evaluate a smart i.v. pump as it was implemented into a redesigned medication-use process. A multidisciplinary team conducted a FMEA to guide the implementation of a smart i.v. pump that was designed to prevent pump programming errors. The smart i.v. pump was equipped with a dose-error reduction system that included a pre-defined drug library in which dosage limits were set for each medication. Monitoring for potential failures and errors occurred for three months postimplementation of FMEA. Specific measures were used to determine the success of the actions that were implemented as a result of the FMEA. The FMEA process at the hospital identified key failure modes in the medication process with the use of the old and new pumps, and actions were taken to avoid errors and adverse events. I.V. pump software and hardware design changes were also recommended. Thirteen of the 18 failure modes reported in practice after pump implementation had been identified by the team. A beneficial outcome of FMEA was the development of a multidisciplinary team that provided the infrastructure for safe technology implementation and effective event investigation after implementation. With the continual updating of i.v. pump software and hardware after implementation, FMEA can be an important starting place for safe technology choice and implementation and can produce site experts to follow technology and process changes over time. FMEA was useful in identifying potential problems in the medication-use process with the implementation of new smart i.v. pumps. Monitoring for system failures and errors after implementation remains necessary.

Prediction of Foreign Object Debris/Damage type based in human factors for aeronautics using logistic regression model

NASA Astrophysics Data System (ADS)

Romo, David Ricardo

Foreign Object Debris/Damage (FOD) has been an issue for military and commercial aircraft manufacturers since the early ages of aviation and aerospace. Currently, aerospace is growing rapidly and the chances of FOD presence are growing as well. One of the principal causes in manufacturing is the human error. The cost associated with human error in commercial and military aircrafts is approximately accountable for 4 billion dollars per year. This problem is currently addressed with prevention programs, elimination techniques, and designation of FOD areas, controlled access, restrictions of personal items entering designated areas, tool accountability, and the use of technology such as Radio Frequency Identification (RFID) tags, etc. All of the efforts mentioned before, have not show a significant occurrence reduction in terms of manufacturing processes. On the contrary, a repetitive path of occurrence is present, and the cost associated has not declined in a significant manner. In order to address the problem, this thesis proposes a new approach using statistical analysis. The effort of this thesis is to create a predictive model using historical categorical data from an aircraft manufacturer only focusing in human error causes. The use of contingency tables, natural logarithm of the odds and probability transformation is used in order to provide the predicted probabilities of each aircraft. A case of study is shown in this thesis in order to show the applied methodology. As a result, this approach is able to predict the possible outcomes of FOD by the workstation/area needed, and monthly predictions per workstation. This thesis is intended to be the starting point of statistical data analysis regarding FOD in human factors. The purpose of this thesis is to identify the areas where human error is the primary cause of FOD occurrence in order to design and implement accurate solutions. The advantages of the proposed methodology can go from the reduction of cost production, quality issues, repair cost, and assembly process time. Finally, a more reliable process is achieved, and the proposed methodology may be used in other aircrafts.

Suppressing relaxation in superconducting qubits by quasiparticle pumping.

PubMed

Gustavsson, Simon; Yan, Fei; Catelani, Gianluigi; Bylander, Jonas; Kamal, Archana; Birenbaum, Jeffrey; Hover, David; Rosenberg, Danna; Samach, Gabriel; Sears, Adam P; Weber, Steven J; Yoder, Jonilyn L; Clarke, John; Kerman, Andrew J; Yoshihara, Fumiki; Nakamura, Yasunobu; Orlando, Terry P; Oliver, William D

2016-12-23

Dynamical error suppression techniques are commonly used to improve coherence in quantum systems. They reduce dephasing errors by applying control pulses designed to reverse erroneous coherent evolution driven by environmental noise. However, such methods cannot correct for irreversible processes such as energy relaxation. We investigate a complementary, stochastic approach to reducing errors: Instead of deterministically reversing the unwanted qubit evolution, we use control pulses to shape the noise environment dynamically. In the context of superconducting qubits, we implement a pumping sequence to reduce the number of unpaired electrons (quasiparticles) in close proximity to the device. A 70% reduction in the quasiparticle density results in a threefold enhancement in qubit relaxation times and a comparable reduction in coherence variability. Copyright © 2016, American Association for the Advancement of Science.

Ar-Ar_Redux: rigorous error propagation of 40Ar/39Ar data, including covariances

NASA Astrophysics Data System (ADS)

Vermeesch, P.

2015-12-01

Rigorous data reduction and error propagation algorithms are needed to realise Earthtime's objective to improve the interlaboratory accuracy of 40Ar/39Ar dating to better than 1% and thereby facilitate the comparison and combination of the K-Ar and U-Pb chronometers. Ar-Ar_Redux is a new data reduction protocol and software program for 40Ar/39Ar geochronology which takes into account two previously underappreciated aspects of the method: 1. 40Ar/39Ar measurements are compositional dataIn its simplest form, the 40Ar/39Ar age equation can be written as: t = log(1+J [40Ar/39Ar-298.5636Ar/39Ar])/λ = log(1 + JR)/λ Where λ is the 40K decay constant and J is the irradiation parameter. The age t does not depend on the absolute abundances of the three argon isotopes but only on their relative ratios. Thus, the 36Ar, 39Ar and 40Ar abundances can be normalised to unity and plotted on a ternary diagram or 'simplex'. Argon isotopic data are therefore subject to the peculiar mathematics of 'compositional data', sensu Aitchison (1986, The Statistical Analysis of Compositional Data, Chapman & Hall). 2. Correlated errors are pervasive throughout the 40Ar/39Ar methodCurrent data reduction protocols for 40Ar/39Ar geochronology propagate the age uncertainty as follows: σ2(t) = [J2 σ2(R) + R2 σ2(J)] / [λ2 (1 + R J)], which implies zero covariance between R and J. In reality, however, significant error correlations are found in every step of the 40Ar/39Ar data acquisition and processing, in both single and multi collector instruments, during blank, interference and decay corrections, age calculation etc. Ar-Ar_Redux revisits every aspect of the 40Ar/39Ar method by casting the raw mass spectrometer data into a contingency table of logratios, which automatically keeps track of all covariances in a compositional context. Application of the method to real data reveals strong correlations (r2 of up to 0.9) between age measurements within a single irradiation batch. Propertly taking into account these correlations significantly improves the precision and accuracy of 40Ar/39Ar data, at no financial cost. A prototype version of Ar-Ar_Redux was written in R and is available from http://redux.london-geochron.com. A standalone GUI is under development.

ADART: an adaptive algebraic reconstruction algorithm for discrete tomography.

PubMed

Maestre-Deusto, F Javier; Scavello, Giovanni; Pizarro, Joaquín; Galindo, Pedro L

2011-08-01

In this paper we suggest an algorithm based on the Discrete Algebraic Reconstruction Technique (DART) which is capable of computing high quality reconstructions from substantially fewer projections than required for conventional continuous tomography. Adaptive DART (ADART) goes a step further than DART on the reduction of the number of unknowns of the associated linear system achieving a significant reduction in the pixel error rate of reconstructed objects. The proposed methodology automatically adapts the border definition criterion at each iteration, resulting in a reduction of the number of pixels belonging to the border, and consequently of the number of unknowns in the general algebraic reconstruction linear system to be solved, being this reduction specially important at the final stage of the iterative process. Experimental results show that reconstruction errors are considerably reduced using ADART when compared to original DART, both in clean and noisy environments.

An urban runoff model designed to inform stormwater management decisions.

PubMed

Beck, Nicole G; Conley, Gary; Kanner, Lisa; Mathias, Margaret

2017-05-15

We present an urban runoff model designed for stormwater managers to quantify runoff reduction benefits of mitigation actions that has lower input data and user expertise requirements than most commonly used models. The stormwater tool to estimate load reductions (TELR) employs a semi-distributed approach, where landscape characteristics and process representation are spatially-lumped within urban catchments on the order of 100 acres (40 ha). Hydrologic computations use a set of metrics that describe a 30-year rainfall distribution, combined with well-tested algorithms for rainfall-runoff transformation and routing to generate average annual runoff estimates for each catchment. User inputs include the locations and specifications for a range of structural best management practice (BMP) types. The model was tested in a set of urban catchments within the Lake Tahoe Basin of California, USA, where modeled annual flows matched that of the observed flows within 18% relative error for 5 of the 6 catchments and had good regional performance for a suite of performance metrics. Comparisons with continuous simulation models showed an average of 3% difference from TELR predicted runoff for a range of hypothetical urban catchments. The model usually identified the dominant BMP outflow components within 5% relative error of event-based measured flow data and simulated the correct proportionality between outflow components. TELR has been implemented as a web-based platform for use by municipal stormwater managers to inform prioritization, report program benefits and meet regulatory reporting requirements (www.swtelr.com). Copyright © 2017. Published by Elsevier Ltd.

Monitoring carbon dioxide from space: Retrieval algorithm and flux inversion based on GOSAT data and using CarbonTracker-China

NASA Astrophysics Data System (ADS)

Yang, Dongxu; Zhang, Huifang; Liu, Yi; Chen, Baozhang; Cai, Zhaonan; Lü, Daren

2017-08-01

Monitoring atmospheric carbon dioxide (CO2) from space-borne state-of-the-art hyperspectral instruments can provide a high precision global dataset to improve carbon flux estimation and reduce the uncertainty of climate projection. Here, we introduce a carbon flux inversion system for estimating carbon flux with satellite measurements under the support of "The Strategic Priority Research Program of the Chinese Academy of Sciences—Climate Change: Carbon Budget and Relevant Issues". The carbon flux inversion system is composed of two separate parts: the Institute of Atmospheric Physics Carbon Dioxide Retrieval Algorithm for Satellite Remote Sensing (IAPCAS), and CarbonTracker-China (CT-China), developed at the Chinese Academy of Sciences. The Greenhouse gases Observing SATellite (GOSAT) measurements are used in the carbon flux inversion experiment. To improve the quality of the IAPCAS-GOSAT retrieval, we have developed a post-screening and bias correction method, resulting in 25%-30% of the data remaining after quality control. Based on these data, the seasonal variation of XCO2 (column-averaged CO2 dry-air mole fraction) is studied, and a strong relation with vegetation cover and population is identified. Then, the IAPCAS-GOSAT XCO2 product is used in carbon flux estimation by CT-China. The net ecosystem CO2 exchange is -0.34 Pg C yr-1 (±0.08 Pg C yr-1), with a large error reduction of 84%, which is a significant improvement on the error reduction when compared with in situ-only inversion.

Utilization of Pharmacy Technicians to Increase the Accuracy of Patient Medication Histories Obtained in the Emergency Department

PubMed Central

Pisupati, Radhika; Nerenberg, Steven F.

2016-01-01

Purpose: The purpose of this study is to determine the accuracy of a pharmacy technician–collected medication history pilot program in the emergency department. This was completed by reviewing all elements of the technician activity by direct observation and by verifying the technician-collected medication list through a second phone call by a pharmacist to the outpatient pharmacy. Methods: This was a retrospective, single-center study conducted from March to April 2015. Four certified pharmacy technicians were trained by a postgraduate year 1 (PGY1) pharmacy practice resident on how to collect, verify, and accurately enter medication histories into the electronic medical record. Accuracy of pharmacy technician–collected medication histories was verified by a pharmacist through observation of their patient interviews, review of technician-completed medication history forms, and by contacting the patient's outpatient pharmacy. Results: The pharmacy technician–completed medication histories resulted in an absolute risk reduction of errors of 50% and a relative risk reduction of errors of 77% (p < .001) in comparison to medication histories collected by non-pharmacy personnel. Conclusion: With high accuracy rates, pharmacy technicians proved to be a valuable asset to the medication history process and can enhance patient safety during care transitions. The results of this study further support the Pharmacy Practice Model Initiative vision to advance the pharmacy technician role to improve the process of medication history taking and reconciliation within the health care system. PMID:27303094

Factors Associated With Barcode Medication Administration Technology That Contribute to Patient Safety: An Integrative Review.

PubMed

Strudwick, Gillian; Reisdorfer, Emilene; Warnock, Caroline; Kalia, Kamini; Sulkers, Heather; Clark, Carrie; Booth, Richard

In an effort to prevent medication errors, barcode medication administration technology has been implemented in many health care organizations. An integrative review was conducted to understand the effect of barcode medication administration technology on medication errors, and characteristics of use demonstrated by nurses contribute to medication safety. Addressing poor system use may support improved patient safety through the reduction of medication administration errors.

A Reduced Dimension Static, Linearized Kalman Filter and Smoother

NASA Technical Reports Server (NTRS)

Fukumori, I.

1995-01-01

An approximate Kalman filter and smoother, based on approximations of the state estimation error covariance matrix, is described. Approximations include a reduction of the effective state dimension, use of a static asymptotic error limit, and a time-invariant linearization of the dynamic model for error integration. The approximations lead to dramatic computational savings in applying estimation theory to large complex systems. Examples of use come from TOPEX/POSEIDON.

Reduction of shading-derived artifacts in skin chromophore imaging without measurements or assumptions about the shape of the subject

NASA Astrophysics Data System (ADS)

Yoshida, Kenichiro; Nishidate, Izumi; Ojima, Nobutoshi; Iwata, Kayoko

2014-01-01

To quantitatively evaluate skin chromophores over a wide region of curved skin surface, we propose an approach that suppresses the effect of the shading-derived error in the reflectance on the estimation of chromophore concentrations, without sacrificing the accuracy of that estimation. In our method, we use multiple regression analysis, assuming the absorbance spectrum as the response variable and the extinction coefficients of melanin, oxygenated hemoglobin, and deoxygenated hemoglobin as the predictor variables. The concentrations of melanin and total hemoglobin are determined from the multiple regression coefficients using compensation formulae (CF) based on the diffuse reflectance spectra derived from a Monte Carlo simulation. To suppress the shading-derived error, we investigated three different combinations of multiple regression coefficients for the CF. In vivo measurements with the forearm skin demonstrated that the proposed approach can reduce the estimation errors that are due to shading-derived errors in the reflectance. With the best combination of multiple regression coefficients, we estimated that the ratio of the error to the chromophore concentrations is about 10%. The proposed method does not require any measurements or assumptions about the shape of the subjects; this is an advantage over other studies related to the reduction of shading-derived errors.

Goldmann Tonometer Prism with an Optimized Error Correcting Applanation Surface.

PubMed

McCafferty, Sean; Lim, Garrett; Duncan, William; Enikov, Eniko; Schwiegerling, Jim

2016-09-01

We evaluate solutions for an applanating surface modification to the Goldmann tonometer prism, which substantially negates the errors due to patient variability in biomechanics. A modified Goldmann or correcting applanation tonometry surface (CATS) prism is presented which was optimized to minimize the intraocular pressure (IOP) error due to corneal thickness, stiffness, curvature, and tear film. Mathematical modeling with finite element analysis (FEA) and manometric IOP referenced cadaver eyes were used to optimize and validate the design. Mathematical modeling of the optimized CATS prism indicates an approximate 50% reduction in each of the corneal biomechanical and tear film errors. Manometric IOP referenced pressure in cadaveric eyes demonstrates substantial equivalence to GAT in nominal eyes with the CATS prism as predicted by modeling theory. A CATS modified Goldmann prism is theoretically able to significantly improve the accuracy of IOP measurement without changing Goldmann measurement technique or interpretation. Clinical validation is needed but the analysis indicates a reduction in CCT error alone to less than ±2 mm Hg using the CATS prism in 100% of a standard population compared to only 54% less than ±2 mm Hg error with the present Goldmann prism. This article presents an easily adopted novel approach and critical design parameters to improve the accuracy of a Goldmann applanating tonometer.

Error reduction and representation in stages (ERRIS) in hydrological modelling for ensemble streamflow forecasting

NASA Astrophysics Data System (ADS)

Li, Ming; Wang, Q. J.; Bennett, James C.; Robertson, David E.

2016-09-01

This study develops a new error modelling method for ensemble short-term and real-time streamflow forecasting, called error reduction and representation in stages (ERRIS). The novelty of ERRIS is that it does not rely on a single complex error model but runs a sequence of simple error models through four stages. At each stage, an error model attempts to incrementally improve over the previous stage. Stage 1 establishes parameters of a hydrological model and parameters of a transformation function for data normalization, Stage 2 applies a bias correction, Stage 3 applies autoregressive (AR) updating, and Stage 4 applies a Gaussian mixture distribution to represent model residuals. In a case study, we apply ERRIS for one-step-ahead forecasting at a range of catchments. The forecasts at the end of Stage 4 are shown to be much more accurate than at Stage 1 and to be highly reliable in representing forecast uncertainty. Specifically, the forecasts become more accurate by applying the AR updating at Stage 3, and more reliable in uncertainty spread by using a mixture of two Gaussian distributions to represent the residuals at Stage 4. ERRIS can be applied to any existing calibrated hydrological models, including those calibrated to deterministic (e.g. least-squares) objectives.

Medication errors: a prospective cohort study of hand-written and computerised physician order entry in the intensive care unit.

PubMed

Shulman, Rob; Singer, Mervyn; Goldstone, John; Bellingan, Geoff

2005-10-05

The study aimed to compare the impact of computerised physician order entry (CPOE) without decision support with hand-written prescribing (HWP) on the frequency, type and outcome of medication errors (MEs) in the intensive care unit. Details of MEs were collected before, and at several time points after, the change from HWP to CPOE. The study was conducted in a London teaching hospital's 22-bedded general ICU. The sampling periods were 28 weeks before and 2, 10, 25 and 37 weeks after introduction of CPOE. The unit pharmacist prospectively recorded details of MEs and the total number of drugs prescribed daily during the data collection periods, during the course of his normal chart review. The total proportion of MEs was significantly lower with CPOE (117 errors from 2429 prescriptions, 4.8%) than with HWP (69 errors from 1036 prescriptions, 6.7%) (p < 0.04). The proportion of errors reduced with time following the introduction of CPOE (p < 0.001). Two errors with CPOE led to patient harm requiring an increase in length of stay and, if administered, three prescriptions with CPOE could potentially have led to permanent harm or death. Differences in the types of error between systems were noted. There was a reduction in major/moderate patient outcomes with CPOE when non-intercepted and intercepted errors were combined (p = 0.01). The mean baseline APACHE II score did not differ significantly between the HWP and the CPOE periods (19.4 versus 20.0, respectively, p = 0.71). Introduction of CPOE was associated with a reduction in the proportion of MEs and an improvement in the overall patient outcome score (if intercepted errors were included). Moderate and major errors, however, remain a significant concern with CPOE.

Revised error propagation of 40Ar/39Ar data, including covariances

NASA Astrophysics Data System (ADS)

Vermeesch, Pieter

2015-12-01

The main advantage of the 40Ar/39Ar method over conventional K-Ar dating is that it does not depend on any absolute abundance or concentration measurements, but only uses the relative ratios between five isotopes of the same element -argon- which can be measured with great precision on a noble gas mass spectrometer. The relative abundances of the argon isotopes are subject to a constant sum constraint, which imposes a covariant structure on the data: the relative amount of any of the five isotopes can always be obtained from that of the other four. Thus, the 40Ar/39Ar method is a classic example of a 'compositional data problem'. In addition to the constant sum constraint, covariances are introduced by a host of other processes, including data acquisition, blank correction, detector calibration, mass fractionation, decay correction, interference correction, atmospheric argon correction, interpolation of the irradiation parameter, and age calculation. The myriad of correlated errors arising during the data reduction are best handled by casting the 40Ar/39Ar data reduction protocol in a matrix form. The completely revised workflow presented in this paper is implemented in a new software platform, Ar-Ar_Redux, which takes raw mass spectrometer data as input and generates accurate 40Ar/39Ar ages and their (co-)variances as output. Ar-Ar_Redux accounts for all sources of analytical uncertainty, including those associated with decay constants and the air ratio. Knowing the covariance matrix of the ages removes the need to consider 'internal' and 'external' uncertainties separately when calculating (weighted) mean ages. Ar-Ar_Redux is built on the same principles as its sibling program in the U-Pb community (U-Pb_Redux), thus improving the intercomparability of the two methods with tangible benefits to the accuracy of the geologic time scale. The program can be downloaded free of charge from http://redux.london-geochron.com.

WE-D-18A-01: Evaluation of Three Commercial Metal Artifact Reduction Methods for CT Simulations in Radiation Therapy Treatment Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, J; Kerns, J; Nute, J

Purpose: To evaluate three commercial metal artifact reduction methods (MAR) in the context of radiation therapy treatment planning. Methods: Three MAR strategies were evaluated: Philips O-MAR, monochromatic imaging using Gemstone Spectral Imaging (GSI) dual energy CT, and monochromatic imaging with metal artifact reduction software (GSIMARs). The Gammex RMI 467 tissue characterization phantom with several metal rods and two anthropomorphic phantoms (pelvic phantom with hip prosthesis and head phantom with dental fillings), were scanned with and without (baseline) metals. Each MAR method was evaluated based on CT number accuracy, metal size accuracy, and reduction in the severity of streak artifacts. CTmore » number difference maps between the baseline and metal scan images were calculated, and the severity of streak artifacts was quantified using the percentage of pixels with >40 HU error (“bad pixels”). Results: Philips O-MAR generally reduced HU errors in the RMI phantom. However, increased errors and induced artifacts were observed for lung materials. GSI monochromatic 70keV images generally showed similar HU errors as 120kVp imaging, while 140keV images reduced errors. GSI-MARs systematically reduced errors compared to GSI monochromatic imaging. All imaging techniques preserved the diameter of a stainless steel rod to within ±1.6mm (2 pixels). For the hip prosthesis, O-MAR reduced the average % bad pixels from 47% to 32%. For GSI 140keV imaging, the percent of bad pixels was reduced from 37% to 29% compared to 120kVp imaging, while GSI-MARs further reduced it to 12%. For the head phantom, none of the MAR methods were particularly successful. Conclusion: The three MAR methods all improve CT images for treatment planning to some degree, but none of them are globally effective for all conditions. The MAR methods were successful for large metal implants in a homogeneous environment (hip prosthesis) but were not successful for the more complicated case of dental artifacts.« less

AKLSQF - LEAST SQUARES CURVE FITTING

NASA Technical Reports Server (NTRS)

Kantak, A. V.

1994-01-01

The Least Squares Curve Fitting program, AKLSQF, computes the polynomial which will least square fit uniformly spaced data easily and efficiently. The program allows the user to specify the tolerable least squares error in the fitting or allows the user to specify the polynomial degree. In both cases AKLSQF returns the polynomial and the actual least squares fit error incurred in the operation. The data may be supplied to the routine either by direct keyboard entry or via a file. AKLSQF produces the least squares polynomial in two steps. First, the data points are least squares fitted using the orthogonal factorial polynomials. The result is then reduced to a regular polynomial using Sterling numbers of the first kind. If an error tolerance is specified, the program starts with a polynomial of degree 1 and computes the least squares fit error. The degree of the polynomial used for fitting is then increased successively until the error criterion specified by the user is met. At every step the polynomial as well as the least squares fitting error is printed to the screen. In general, the program can produce a curve fitting up to a 100 degree polynomial. All computations in the program are carried out under Double Precision format for real numbers and under long integer format for integers to provide the maximum accuracy possible. AKLSQF was written for an IBM PC X/AT or compatible using Microsoft's Quick Basic compiler. It has been implemented under DOS 3.2.1 using 23K of RAM. AKLSQF was developed in 1989.

A model and variance reduction method for computing statistical outputs of stochastic elliptic partial differential equations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vidal-Codina, F., E-mail: fvidal@mit.edu; Nguyen, N.C., E-mail: cuongng@mit.edu; Giles, M.B., E-mail: mike.giles@maths.ox.ac.uk

We present a model and variance reduction method for the fast and reliable computation of statistical outputs of stochastic elliptic partial differential equations. Our method consists of three main ingredients: (1) the hybridizable discontinuous Galerkin (HDG) discretization of elliptic partial differential equations (PDEs), which allows us to obtain high-order accurate solutions of the governing PDE; (2) the reduced basis method for a new HDG discretization of the underlying PDE to enable real-time solution of the parameterized PDE in the presence of stochastic parameters; and (3) a multilevel variance reduction method that exploits the statistical correlation among the different reduced basismore » approximations and the high-fidelity HDG discretization to accelerate the convergence of the Monte Carlo simulations. The multilevel variance reduction method provides efficient computation of the statistical outputs by shifting most of the computational burden from the high-fidelity HDG approximation to the reduced basis approximations. Furthermore, we develop a posteriori error estimates for our approximations of the statistical outputs. Based on these error estimates, we propose an algorithm for optimally choosing both the dimensions of the reduced basis approximations and the sizes of Monte Carlo samples to achieve a given error tolerance. We provide numerical examples to demonstrate the performance of the proposed method.« less

New methods of measuring and calibrating robots

NASA Astrophysics Data System (ADS)

Janocha, Hartmut; Diewald, Bernd

1995-10-01

ISO 9283 and RIA R15.05 define industrial robot parameters which are applied to compare the efficiency of different robots. Hitherto, however, no suitable measurement systems have been available. ICAROS is a system which combines photogrammetrical procedures with an inertial navigation system. For the first time, this combination allows the high-precision static and dynamic measurement of the position as well as of the orientation of the robot endeffector. Thus, not only the measuring data for the determination of all industrial robot parameters can be acquired. By integration of a new over-all-calibration procedure, ICAROS also allows the reduction of the absolute robot pose errors to the range of its repeatability. The integration of both system components as well as measurement and calibration results are presented in this paper, using a six-axes robot as example. A further approach also presented here takes into consideration not only the individual robot errors but also the tolerances of workpieces. This allows the adjustment of off-line programs of robots based on inexact or idealized CAD data in any pose. Thus the robot position which is defined relative to the workpiece to be processed, is achieved as required. This includes the possibility to transfer teached robot programs to other devices without additional expenditure. The adjustment is based on the measurement of the robot position using two miniaturized CCD cameras mounted near the endeffector which are carried along by the robot during the correction phase. In the area viewed by both cameras, the robot position is determined in relation to prominent geometry elements, e.g. lines or holes. The scheduled data to be compared therewith can either be calculated in modern off-line programming systems during robot programming, or they can be determined at the so-called master robot if a transfer of the robot program is desired.

Nonlinear method for including the mass uncertainty of standards and the system measurement errors in the fitting of calibration curves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pickles, W.L.; McClure, J.W.; Howell, R.H.

1978-01-01

A sophisticated non-linear multiparameter fitting program has been used to produce a best fit calibration curve for the response of an x-ray fluorescence analyzer to uranium nitrate, freeze dried, 0.2% accurate, gravimetric standards. The program is based on unconstrained minimization subroutine, VA02A. The program considers the mass values of the gravimetric standards as parameters to be fit along with the normal calibration curve parameters. The fitting procedure weights with the system errors and the mass errors in a consistent way. The resulting best fit calibration curve parameters reflect the fact that the masses of the standard samples are measured quantitiesmore » with a known error. Error estimates for the calibration curve parameters can be obtined from the curvature of the Chi-Squared Matrix or from error relaxation techniques. It has been shown that non-dispersive x-ray fluorescence analysis of 0.1 to 1 mg freeze-dried UNO/sub 3/ can have an accuracy of 0.2% in 1000 sec.« less

Use of a non-linear method for including the mass uncertainty of gravimetric standards and system measurement errors in the fitting of calibration curves for XRFA freeze-dried UNO/sub 3/ standards

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pickles, W.L.; McClure, J.W.; Howell, R.H.

1978-05-01

A sophisticated nonlinear multiparameter fitting program was used to produce a best fit calibration curve for the response of an x-ray fluorescence analyzer to uranium nitrate, freeze dried, 0.2% accurate, gravimetric standards. The program is based on unconstrained minimization subroutine, VA02A. The program considers the mass values of the gravimetric standards as parameters to be fit along with the normal calibration curve parameters. The fitting procedure weights with the system errors and the mass errors in a consistent way. The resulting best fit calibration curve parameters reflect the fact that the masses of the standard samples are measured quantities withmore » a known error. Error estimates for the calibration curve parameters can be obtained from the curvature of the ''Chi-Squared Matrix'' or from error relaxation techniques. It was shown that nondispersive XRFA of 0.1 to 1 mg freeze-dried UNO/sub 3/ can have an accuracy of 0.2% in 1000 s.« less

Error analysis and correction in wavefront reconstruction from the transport-of-intensity equation

PubMed Central

Barbero, Sergio; Thibos, Larry N.

2007-01-01

Wavefront reconstruction from the transport-of-intensity equation (TIE) is a well-posed inverse problem given smooth signals and appropriate boundary conditions. However, in practice experimental errors lead to an ill-condition problem. A quantitative analysis of the effects of experimental errors is presented in simulations and experimental tests. The relative importance of numerical, misalignment, quantization, and photodetection errors are shown. It is proved that reduction of photodetection noise by wavelet filtering significantly improves the accuracy of wavefront reconstruction from simulated and experimental data. PMID:20052302

A rigorous approach to self-checking programming

NASA Technical Reports Server (NTRS)

Hua, Kien A.; Abraham, Jacob A.

1986-01-01

Self-checking programming is shown to be an effective concurrent error detection technique. The reliability of a self-checking program however relies on the quality of its assertion statements. A self-checking program written without formal guidelines could provide a poor coverage of the errors. A constructive technique for self-checking programming is presented. A Structured Program Design Language (SPDL) suitable for self-checking software development is defined. A set of formal rules, was also developed, that allows the transfromation of SPDL designs into self-checking designs to be done in a systematic manner.

Elevation Change of the Southern Greenland Ice Sheet from Satellite Radar Altimeter Data

NASA Technical Reports Server (NTRS)

Haines, Bruce J.

1999-01-01

Long-term changes in the thickness of the polar ice sheets are important indicators of climate change. Understanding the contributions to the global water mass balance from the accumulation or ablation of grounded ice in Greenland and Antarctica is considered crucial for determining the source of the about 2 mm/yr sea-level rise in the last century. Though the Antarctic ice sheet is much larger than its northern counterpart, the Greenland ice sheet is more likely to undergo dramatic changes in response to a warming trend. This can be attributed to the warmer Greenland climate, as well as a potential for amplification of a global warming trend in the polar regions of the Northern Hemisphere. In collaboration with Drs. Curt Davis and Craig Kluever of the University of Missouri, we are using data from satellite radar altimeters to measure changes in the elevation of the Southern Greenland ice sheet from 1978 to the present. Difficulties with systematic altimeter measurement errors, particularly in intersatellite comparisons, beset earlier studies of the Greenland ice sheet thickness. We use altimeter data collected contemporaneously over the global ocean to establish a reference for correcting ice-sheet data. In addition, the waveform data from the ice-sheet radar returns are reprocessed to better determine the range from the satellite to the ice surface. At JPL, we are focusing our efforts principally on the reduction of orbit errors and range biases in the measurement systems on the various altimeter missions. Our approach emphasizes global characterization and reduction of the long-period orbit errors and range biases using altimeter data from NASA's Ocean Pathfinder program. Along-track sea-height residuals are sequentially filtered and backwards smoothed, and the radial orbit errors are modeled as sinusoids with a wavelength equal to one revolution of the satellite. The amplitudes of the sinusoids are treated as exponentially-correlated noise processes with a time-constant of six days. Measurement errors (e.g., altimeter range bias) are simultaneously recovered as constant parameters. The corrections derived from the global ocean analysis are then applied over the Greenland ice sheet. The orbit error and measurement bias corrections for different missions are developed in a single framework to enable robust linkage of ice-sheet measurements from 1978 to the present. In 1998, we completed our re-evaluation of the 1978 Seasat and 1985-1989 Geosat Exact Repeat Mission data. The estimates of ice thickness over Southern Greenland (south of 72N and above 2000 m) from 1978 to 1988 show large regional variations (+/-18 cm/yr), but yield an overall rate of +1.5 +/- 0.5 cm/yr (one standard error). Accounting for systematic errors, the estimate may not be significantly different from the null growth rate. The average elevation change from 1978 to 1988 is too small to assess whether the Greenland ice sheet is undergoing a long-term change.

Space Trajectory Error Analysis Program (STEAP) for halo orbit missions. Volume 2: Programmer's manual

NASA Technical Reports Server (NTRS)

Byrnes, D. V.; Carney, P. C.; Underwood, J. W.; Vogt, E. D.

1974-01-01

The six month effort was responsible for the development, test, conversion, and documentation of computer software for the mission analysis of missions to halo orbits about libration points in the earth-sun system. The software consisting of two programs called NOMNAL and ERRAN is part of the Space Trajectories Error Analysis Programs. The program NOMNAL targets a transfer trajectory from earth on a given launch date to a specified halo orbit on a required arrival date. Either impulsive or finite thrust insertion maneuvers into halo orbit are permitted by the program. The transfer trajectory is consistent with a realistic launch profile input by the user. The second program ERRAN conducts error analyses of the targeted transfer trajectory. Measurements including range, doppler, star-planet angles, and apparent planet diameter are processed in a Kalman-Schmidt filter to determine the trajectory knowledge uncertainty.

CADNA: a library for estimating round-off error propagation

NASA Astrophysics Data System (ADS)

Jézéquel, Fabienne; Chesneaux, Jean-Marie

2008-06-01

The CADNA library enables one to estimate round-off error propagation using a probabilistic approach. With CADNA the numerical quality of any simulation program can be controlled. Furthermore by detecting all the instabilities which may occur at run time, a numerical debugging of the user code can be performed. CADNA provides new numerical types on which round-off errors can be estimated. Slight modifications are required to control a code with CADNA, mainly changes in variable declarations, input and output. This paper describes the features of the CADNA library and shows how to interpret the information it provides concerning round-off error propagation in a code. Program summaryProgram title:CADNA Catalogue identifier:AEAT_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEAT_v1_0.html Program obtainable from:CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions:Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.:53 420 No. of bytes in distributed program, including test data, etc.:566 495 Distribution format:tar.gz Programming language:Fortran Computer:PC running LINUX with an i686 or an ia64 processor, UNIX workstations including SUN, IBM Operating system:LINUX, UNIX Classification:4.14, 6.5, 20 Nature of problem:A simulation program which uses floating-point arithmetic generates round-off errors, due to the rounding performed at each assignment and at each arithmetic operation. Round-off error propagation may invalidate the result of a program. The CADNA library enables one to estimate round-off error propagation in any simulation program and to detect all numerical instabilities that may occur at run time. Solution method:The CADNA library [1] implements Discrete Stochastic Arithmetic [2-4] which is based on a probabilistic model of round-off errors. The program is run several times with a random rounding mode generating different results each time. From this set of results, CADNA estimates the number of exact significant digits in the result that would have been computed with standard floating-point arithmetic. Restrictions:CADNA requires a Fortran 90 (or newer) compiler. In the program to be linked with the CADNA library, round-off errors on complex variables cannot be estimated. Furthermore array functions such as product or sum must not be used. Only the arithmetic operators and the abs, min, max and sqrt functions can be used for arrays. Running time:The version of a code which uses CADNA runs at least three times slower than its floating-point version. This cost depends on the computer architecture and can be higher if the detection of numerical instabilities is enabled. In this case, the cost may be related to the number of instabilities detected. References:The CADNA library, URL address: http://www.lip6.fr/cadna. J.-M. Chesneaux, L'arithmétique Stochastique et le Logiciel CADNA, Habilitation á diriger des recherches, Université Pierre et Marie Curie, Paris, 1995. J. Vignes, A stochastic arithmetic for reliable scientific computation, Math. Comput. Simulation 35 (1993) 233-261. J. Vignes, Discrete stochastic arithmetic for validating results of numerical software, Numer. Algorithms 37 (2004) 377-390.

High accuracy switched-current circuits using an improved dynamic mirror

NASA Technical Reports Server (NTRS)

Zweigle, G.; Fiez, T.

1991-01-01

The switched-current technique, a recently developed circuit approach to analog signal processing, has emerged as an alternative/compliment to the well established switched-capacitor circuit technique. High speed switched-current circuits offer potential cost and power savings over slower switched-capacitor circuits. Accuracy improvements are a primary concern at this stage in the development of the switched-current technique. Use of the dynamic current mirror has produced circuits that are insensitive to transistor matching errors. The dynamic current mirror has been limited by other sources of error including clock-feedthrough and voltage transient errors. In this paper we present an improved switched-current building block using the dynamic current mirror. Utilizing current feedback the errors due to current imbalance in the dynamic current mirror are reduced. Simulations indicate that this feedback can reduce total harmonic distortion by as much as 9 dB. Additionally, we have developed a clock-feedthrough reduction scheme for which simulations reveal a potential 10 dB total harmonic distortion improvement. The clock-feedthrough reduction scheme also significantly reduces offset errors and allows for cancellation with a constant current source. Experimental results confirm the simulated improvements.

Mathemagical Computing: Order of Operations and New Software.

ERIC Educational Resources Information Center

Ecker, Michael W.

1989-01-01

Describes mathematical problems which occur when using the computer as a calculator. Considers errors in BASIC calculation and the order of mathematical operations. Identifies errors in spreadsheet and calculator programs. Comments on sorting programs and provides a source for Mathemagical Black Holes. (MVL)

Safety coaches in radiology: decreasing human error and minimizing patient harm.

PubMed

Dickerson, Julie M; Koch, Bernadette L; Adams, Janet M; Goodfriend, Martha A; Donnelly, Lane F

2010-09-01

Successful programs to improve patient safety require a component aimed at improving safety culture and environment, resulting in a reduced number of human errors that could lead to patient harm. Safety coaching provides peer accountability. It involves observing for safety behaviors and use of error prevention techniques and provides immediate feedback. For more than a decade, behavior-based safety coaching has been a successful strategy for reducing error within the context of occupational safety in industry. We describe the use of safety coaches in radiology. Safety coaches are an important component of our comprehensive patient safety program.

The Michelson Stellar Interferometer Error Budget for Triple Triple-Satellite Configuration

NASA Technical Reports Server (NTRS)

Marathay, Arvind S.; Shiefman, Joe

1996-01-01

This report presents the results of a study of the instrumentation tolerances for a conventional style Michelson stellar interferometer (MSI). The method used to determine the tolerances was to determine the change, due to the instrument errors, in the measured fringe visibility and phase relative to the ideal values. The ideal values are those values of fringe visibility and phase that would be measured by a perfect MSI and are attributable solely to the object being detected. Once the functional relationship for changes in visibility and phase as a function of various instrument errors is understood it is then possible to set limits on the instrument errors in order to ensure that the measured visibility and phase are different from the ideal values by no more than some specified amount. This was done as part of this study. The limits we obtained are based on a visibility error of no more than 1% and a phase error of no more than 0.063 radians (this comes from 1% of 2(pi) radians). The choice of these 1% limits is supported in the literture. The approach employed in the study involved the use of ASAP (Advanced System Analysis Program) software provided by Breault Research Organization, Inc., in conjunction with parallel analytical calculations. The interferometer accepts object radiation into two separate arms each consisting of an outer mirror, an inner mirror, a delay line (made up of two moveable mirrors and two static mirrors), and a 10:1 afocal reduction telescope. The radiation coming out of both arms is incident on a slit plane which is opaque with two openings (slits). One of the two slits is centered directly under one of the two arms of the interferometer and the other slit is centered directly under the other arm. The slit plane is followed immediately by an ideal combining lens which images the radiation in the fringe plane (also referred to subsequently as the detector plane).

Continuous slope-area discharge records in Maricopa County, Arizona, 2004–2012

USGS Publications Warehouse

Wiele, Stephen M.; Heaton, John W.; Bunch, Claire E.; Gardner, David E.; Smith, Christopher F.

2015-12-29

Analyses of sources of errors and the impact stage data errors have on calculated discharge time series are considered, along with issues in data reduction. Steeper, longer stream reaches are generally less sensitive to measurement error. Other issues considered are pressure transducer drawdown, capture of flood peaks with discrete stage data, selection of stage record for development of rating curves, and minimum stages for the calculation of discharge.

On the equivalence of Gaussian elimination and Gauss-Jordan reduction in solving linear equations

NASA Technical Reports Server (NTRS)

Tsao, Nai-Kuan

1989-01-01

A novel general approach to round-off error analysis using the error complexity concepts is described. This is applied to the analysis of the Gaussian Elimination and Gauss-Jordan scheme for solving linear equations. The results show that the two algorithms are equivalent in terms of our error complexity measures. Thus the inherently parallel Gauss-Jordan scheme can be implemented with confidence if parallel computers are available.

Skeletal Mechanism Generation of Surrogate Jet Fuels for Aeropropulsion Modeling

NASA Astrophysics Data System (ADS)

Sung, Chih-Jen; Niemeyer, Kyle E.

2010-05-01

A novel implementation for the skeletal reduction of large detailed reaction mechanisms using the directed relation graph with error propagation and sensitivity analysis (DRGEPSA) is developed and presented with skeletal reductions of two important hydrocarbon components, n-heptane and n-decane, relevant to surrogate jet fuel development. DRGEPSA integrates two previously developed methods, directed relation graph-aided sensitivity analysis (DRGASA) and directed relation graph with error propagation (DRGEP), by first applying DRGEP to efficiently remove many unimportant species prior to sensitivity analysis to further remove unimportant species, producing an optimally small skeletal mechanism for a given error limit. It is illustrated that the combination of the DRGEP and DRGASA methods allows the DRGEPSA approach to overcome the weaknesses of each previous method, specifically that DRGEP cannot identify all unimportant species and that DRGASA shields unimportant species from removal.

Reducing visual deficits caused by refractive errors in school and preschool children: results of a pilot school program in the Andean region of Apurimac, Peru.

PubMed

Latorre-Arteaga, Sergio; Gil-González, Diana; Enciso, Olga; Phelan, Aoife; García-Muñoz, Angel; Kohler, Johannes

2014-01-01

Refractive error is defined as the inability of the eye to bring parallel rays of light into focus on the retina, resulting in nearsightedness (myopia), farsightedness (Hyperopia) or astigmatism. Uncorrected refractive error in children is associated with increased morbidity and reduced educational opportunities. Vision screening (VS) is a method for identifying children with visual impairment or eye conditions likely to lead to visual impairment. To analyze the utility of vision screening conducted by teachers and to contribute to a better estimation of the prevalence of childhood refractive errors in Apurimac, Peru. Design : A pilot vision screening program in preschool (Group I) and elementary school children (Group II) was conducted with the participation of 26 trained teachers. Children whose visual acuity was<6/9 [20/30] (Group I) and ≤ 6/9 (Group II) in one or both eyes, measured with the Snellen Tumbling E chart at 6 m, were referred for a comprehensive eye exam. Specificity and positive predictive value to detect refractive error were calculated against clinical examination. Program assessment with participants was conducted to evaluate outcomes and procedures. A total sample of 364 children aged 3-11 were screened; 45 children were examined at Centro Oftalmológico Monseñor Enrique Pelach (COMEP) Eye Hospital. Prevalence of refractive error was 6.2% (Group I) and 6.9% (Group II); specificity of teacher vision screening was 95.8% and 93.0%, while positive predictive value was 59.1% and 47.8% for each group, respectively. Aspects highlighted to improve the program included extending training, increasing parental involvement, and helping referred children to attend the hospital. Prevalence of refractive error in children is significant in the region. Vision screening performed by trained teachers is a valid intervention for early detection of refractive error, including screening of preschool children. Program sustainability and improvements in education and quality of life resulting from childhood vision screening require further research.

Sleep-Dependent Reductions in Reality-Monitoring Errors Arise from More Conservative Decision Criteria

ERIC Educational Resources Information Center

Westerberg, Carmen E.; Hawkins, Christopher A.; Rendon, Lauren

2018-01-01

Reality-monitoring errors occur when internally generated thoughts are remembered as external occurrences. We hypothesized that sleep-dependent memory consolidation could reduce them by strengthening connections between items and their contexts during an afternoon nap. Participants viewed words and imagined their referents. Pictures of the…

Textbook Error: Short Circuiting on Electrochemical Cell

ERIC Educational Resources Information Center

Bonicamp, Judith M.; Clark, Roy W.

2007-01-01

Short circuiting an electrochemical cell is an unreported but persistent error in the electrochemistry textbooks. It is suggested that diagrams depicting a cell delivering usable current to a load be postponed, the theory of open-circuit galvanic cells is explained, the voltages from the tables of standard reduction potentials is calculated and…

Airborne data measurement system errors reduction through state estimation and control optimization

NASA Astrophysics Data System (ADS)

Sebryakov, G. G.; Muzhichek, S. M.; Pavlov, V. I.; Ermolin, O. V.; Skrinnikov, A. A.

2018-02-01

The paper discusses the problem of airborne data measurement system errors reduction through state estimation and control optimization. The approaches are proposed based on the methods of experiment design and the theory of systems with random abrupt structure variation. The paper considers various control criteria as applied to an aircraft data measurement system. The physics of criteria is explained, the mathematical description and the sequence of steps for each criterion application is shown. The formula is given for airborne data measurement system state vector posterior estimation based for systems with structure variations.

Increased instrument intelligence--can it reduce laboratory error?

PubMed

Jekelis, Albert W

2005-01-01

Recent literature has focused on the reduction of laboratory errors and the potential impact on patient management. This study assessed the intelligent, automated preanalytical process-control abilities in newer generation analyzers as compared with older analyzers and the impact on error reduction. Three generations of immuno-chemistry analyzers were challenged with pooled human serum samples for a 3-week period. One of the three analyzers had an intelligent process of fluidics checks, including bubble detection. Bubbles can cause erroneous results due to incomplete sample aspiration. This variable was chosen because it is the most easily controlled sample defect that can be introduced. Traditionally, lab technicians have had to visually inspect each sample for the presence of bubbles. This is time consuming and introduces the possibility of human error. Instruments with bubble detection may be able to eliminate the human factor and reduce errors associated with the presence of bubbles. Specific samples were vortexed daily to introduce a visible quantity of bubbles, then immediately placed in the daily run. Errors were defined as a reported result greater than three standard deviations below the mean and associated with incomplete sample aspiration of the analyte of the individual analyzer Three standard deviations represented the target limits of proficiency testing. The results of the assays were examined for accuracy and precision. Efficiency, measured as process throughput, was also measured to associate a cost factor and potential impact of the error detection on the overall process. The analyzer performance stratified according to their level of internal process control The older analyzers without bubble detection reported 23 erred results. The newest analyzer with bubble detection reported one specimen incorrectly. The precision and accuracy of the nonvortexed specimens were excellent and acceptable for all three analyzers. No errors were found in the nonvortexed specimens. There were no significant differences in overall process time for any of the analyzers when tests were arranged in an optimal configuration. The analyzer with advanced fluidic intelligence demostrated the greatest ability to appropriately deal with an incomplete aspiration by not processing and reporting a result for the sample. This study suggests that preanalytical process-control capabilities could reduce errors. By association, it implies that similar intelligent process controls could favorably impact the error rate and, in the case of this instrument, do it without negatively impacting process throughput. Other improvements may be realized as a result of having an intelligent error-detection process including further reduction in misreported results, fewer repeats, less operator intervention, and less reagent waste.

The Effects of Discrete-Trial Training Commission Errors on Learner Outcomes: An Extension

ERIC Educational Resources Information Center

Jenkins, Sarah R.; Hirst, Jason M.; DiGennaro Reed, Florence D.

2015-01-01

We conducted a parametric analysis of treatment integrity errors during discrete-trial training and investigated the effects of three integrity conditions (0, 50, or 100 % errors of commission) on performance in the presence and absence of programmed errors. The presence of commission errors impaired acquisition for three of four participants.…

Human error in hospitals and industrial accidents: current concepts.

PubMed

Spencer, F C

2000-10-01

Most data concerning errors and accidents are from industrial accidents and airline injuries. General Electric, Alcoa, and Motorola, among others, all have reported complex programs that resulted in a marked reduction in frequency of worker injuries. In the field of medicine, however, with the outstanding exception of anesthesiology, there is a paucity of information, most reports referring to the 1984 Harvard-New York State Study, more than 16 years ago. This scarcity of information indicates the complexity of the problem. It seems very unlikely that simple exhortation or additional regulations will help because the problem lies principally in the multiple human-machine interfaces that constitute modern medical care. The absence of success stories also indicates that the best methods have to be learned by experience. A liaison with industry should be helpful, although the varieties of human illness are far different from a standardized manufacturing process. Concurrent with the studies of industrial and nuclear accidents, cognitive psychologists have intensively studied how the brain stores and retrieves information. Several concepts have emerged. First, errors are not character defects to be treated by the classic approach of discipline and education, but are byproducts of normal thinking that occur frequently. Second, major accidents are rarely causedby a single error; instead, they are often a combination of chronic system errors, termed latent errors. Identifying and correcting these latent errors should be the principal focus for corrective planning rather than searching for an individual culprit. This nonpunitive concept of errors is a key basis for an effective reporting system, brilliantly demonstrated in aviation with the ASRS system developed more than 25 years ago. The ASRS currently receives more than 30,000 reports annually and is credited with the remarkable increase in safety of airplane travel. Adverse drug events constitute about 25% of hospital errors. In the future, the combination of new drugs and a vast amount of new information will additionally increase the possibilities for error. Two major advances in recent years have been computerization and active participation of the pharmacist with dispensing medications. Further investigation of hospital errors should concentrate primarily on latent system errors. Significant system changes will require broad staff participation throughout the hospital. This, in turn, should foster development of an institutional safety culture, rather than the popular attitude that patient safety responsibility is concentrated in the Quality Assurance-Risk Management division. Quality of service and patient safety are closely intertwined.

Watch what you type: the role of visual feedback from the screen and hands in skilled typewriting.

PubMed

Snyder, Kristy M; Logan, Gordon D; Yamaguchi, Motonori

2015-01-01

Skilled typing is controlled by two hierarchically structured processing loops (Logan & Crump, 2011): The outer loop, which produces words, commands the inner loop, which produces keystrokes. Here, we assessed the interplay between the two loops by investigating how visual feedback from the screen (responses either were or were not echoed on the screen) and the hands (the hands either were or were not covered with a box) influences the control of skilled typing. Our results indicated, first, that the reaction time of the first keystroke was longer when responses were not echoed than when they were. Also, the interkeystroke interval (IKSI) was longer when the hands were covered than when they were visible, and the IKSI for responses that were not echoed was longer when explicit error monitoring was required (Exp. 2) than when it was not required (Exp. 1). Finally, explicit error monitoring was more accurate when response echoes were present than when they were absent, and implicit error monitoring (i.e., posterror slowing) was not influenced by visual feedback from the screen or the hands. These findings suggest that the outer loop adjusts the inner-loop timing parameters to compensate for reductions in visual feedback. We suggest that these adjustments are preemptive control strategies designed to execute keystrokes more cautiously when visual feedback from the hands is absent, to generate more cautious motor programs when visual feedback from the screen is absent, and to enable enough time for the outer loop to monitor keystrokes when visual feedback from the screen is absent and explicit error reports are required.

78 FR 11237 - Public Hearing

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-15

... management of human error in its operations and system safety programs, and the status of PTC implementation... UP's safety management policies and programs associated with human error, operational accident and... Chairman of the Board of Inquiry 2. Introduction of the Board of Inquiry and Technical Panel 3...

42 CFR 431.992 - Corrective action plan.

Code of Federal Regulations, 2010 CFR

2010-10-01

... CMS, designed to reduce improper payments in each program based on its analysis of the error causes in... State must take the following actions: (1) Data analysis. States must conduct data analysis such as reviewing clusters of errors, general error causes, characteristics, and frequency of errors that are...

42 CFR 431.992 - Corrective action plan.

Code of Federal Regulations, 2011 CFR

2011-10-01

... CMS, designed to reduce improper payments in each program based on its analysis of the error causes in... State must take the following actions: (1) Data analysis. States must conduct data analysis such as reviewing clusters of errors, general error causes, characteristics, and frequency of errors that are...

Integrating technology to improve medication administration.

PubMed

Prusch, Amanda E; Suess, Tina M; Paoletti, Richard D; Olin, Stephen T; Watts, Starann D

2011-05-01

The development, implementation, and evaluation of an i.v. interoperability program to advance medication safety at the bedside are described. I.V. interoperability integrates intelligent infusion devices (IIDs), the bar-code-assisted medication administration system, and the electronic medication administration record system into a bar-code-driven workflow that populates provider-ordered, pharmacist-validated infusion parameters on IIDs. The purpose of this project was to improve medication safety through the integration of these technologies and decrease the potential for error during i.v. medication administration. Four key phases were essential to developing and implementing i.v. interoperability: (a) preparation, (b) i.v. interoperability pilot, (c) preliminary validation, and (d) expansion. The establishment of pharmacy involvement in i.v. interoperability resulted in two additional safety checks: pharmacist infusion rate oversight and nurse independent validation of the autoprogrammed rate. After instituting i.v. interoperability, monthly compliance to the telemetry drug library increased to a mean ± S.D. of 72.1% ± 2.1% from 56.5% ± 1.5%, and the medical-surgical nursing unit's drug library monthly compliance rate increased to 58.6% ± 2.9% from 34.1% ± 2.6% (p < 0.001 for both comparisons). The number of manual pump edits decreased with both telemetry and medical-surgical drug libraries, demonstrating a reduction from 56.9 ± 12.8 to 14.2 ± 3.9 and from 61.2 ± 15.4 to 14.7 ± 3.8, respectively (p < 0.001 for both comparisons). Through the integration and incorporation of pharmacist oversight for rate changes, the telemetry and medical-surgical patient care areas demonstrated a 32% reduction in reported monthly errors involving i.v. administration of heparin. By integrating two stand-alone technologies, i.v. interoperability was implemented to improve medication administration. Medication errors were reduced, nursing workflow was simplified, and pharmacists became involved in checking infusion rates of i.v. medications.

GDF v2.0, an enhanced version of GDF

NASA Astrophysics Data System (ADS)

Tsoulos, Ioannis G.; Gavrilis, Dimitris; Dermatas, Evangelos

2007-12-01

An improved version of the function estimation program GDF is presented. The main enhancements of the new version include: multi-output function estimation, capability of defining custom functions in the grammar and selection of the error function. The new version has been evaluated on a series of classification and regression datasets, that are widely used for the evaluation of such methods. It is compared to two known neural networks and outperforms them in 5 (out of 10) datasets. Program summaryTitle of program: GDF v2.0 Catalogue identifier: ADXC_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXC_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 98 147 No. of bytes in distributed program, including test data, etc.: 2 040 684 Distribution format: tar.gz Programming language: GNU C++ Computer: The program is designed to be portable in all systems running the GNU C++ compiler Operating system: Linux, Solaris, FreeBSD RAM: 200000 bytes Classification: 4.9 Does the new version supersede the previous version?: Yes Nature of problem: The technique of function estimation tries to discover from a series of input data a functional form that best describes them. This can be performed with the use of parametric models, whose parameters can adapt according to the input data. Solution method: Functional forms are being created by genetic programming which are approximations for the symbolic regression problem. Reasons for new version: The GDF package was extended in order to be more flexible and user customizable than the old package. The user can extend the package by defining his own error functions and he can extend the grammar of the package by adding new functions to the function repertoire. Also, the new version can perform function estimation of multi-output functions and it can be used for classification problems. Summary of revisions: The following features have been added to the package GDF: Multi-output function approximation. The package can now approximate any function f:R→R. This feature gives also to the package the capability of performing classification and not only regression. User defined function can be added to the repertoire of the grammar, extending the regression capabilities of the package. This feature is limited to 3 functions, but easily this number can be increased. Capability of selecting the error function. The package offers now to the user apart from the mean square error other error functions such as: mean absolute square error, maximum square error. Also, user defined error functions can be added to the set of error functions. More verbose output. The main program displays more information to the user as well as the default values for the parameters. Also, the package gives to the user the capability to define an output file, where the output of the gdf program for the testing set will be stored after the termination of the process. Additional comments: A technical report describing the revisions, experiments and test runs is packaged with the source code. Running time: Depending on the train data.

Feedback controlled optics with wavefront compensation

NASA Technical Reports Server (NTRS)

Breckenridge, William G. (Inventor); Redding, David C. (Inventor)

1993-01-01

The sensitivity model of a complex optical system obtained by linear ray tracing is used to compute a control gain matrix by imposing the mathematical condition for minimizing the total wavefront error at the optical system's exit pupil. The most recent deformations or error states of the controlled segments or optical surfaces of the system are then assembled as an error vector, and the error vector is transformed by the control gain matrix to produce the exact control variables which will minimize the total wavefront error at the exit pupil of the optical system. These exact control variables are then applied to the actuators controlling the various optical surfaces in the system causing the immediate reduction in total wavefront error observed at the exit pupil of the optical system.

A Randomized Controlled Trial Translating the Diabetes Prevention Program to a University Worksite, Ohio, 2012–2014

PubMed Central

Weinhold, Kellie R.; Marrero, David G.; Nagaraja, Haikady N.; Focht, Brian C.; Gascon, Gregg M.

2015-01-01

Introduction Working adults spend much time at the workplace, an ideal setting for wellness programs targeting weight loss and disease prevention. Few randomized trials have evaluated the efficacy of worksite diabetes prevention programs.This study evaluated the efficacy of a worksite lifestyle intervention on metabolic and behavioral risk factors compared with usual care. Methods A pretest–posttest control group design with 3-month follow-up was used. Participants with prediabetes were recruited from a university worksite and randomized to receive a 16-week lifestyle intervention (n = 35) or usual care (n = 34). Participants were evaluated at baseline, postintervention, and 3-month follow-up. Dietary intake was measured by a food frequency questionnaire and level of physical activity by accelerometers. Repeated measures analysis of variance compared the change in outcomes between and within groups. Results Mean (standard error [SE]) weight loss was greater in the intervention (−5.5% [0.6%]) than in the control (−0.4% [0.5%]) group (P < .001) postintervention and was sustained at 3-month follow-up (P < .001). Mean (SE) reductions in fasting glucose were greater in the intervention (−8.6 [1.6] mg/dL) than in the control (−3.7 [1.6] mg/dL) group (P = .02) postintervention; both groups had significant glucose reductions at 3-month follow-up (P < .001). In the intervention group, the intake of total energy and the percentage of energy from all fats, saturated fats, and trans fats decreased, and the intake of dietary fiber increased (all P < .01) postintervention. Conclusion The worksite intervention improved metabolic and behavioral risk factors among employees with prediabetes. The long-term impact on diabetes prevention and program sustainability warrant further investigation. PMID:26605710

A Randomized Controlled Trial Translating the Diabetes Prevention Program to a University Worksite, Ohio, 2012-2014.

PubMed

Weinhold, Kellie R; Miller, Carla K; Marrero, David G; Nagaraja, Haikady N; Focht, Brian C; Gascon, Gregg M

2015-11-25

Working adults spend much time at the workplace, an ideal setting for wellness programs targeting weight loss and disease prevention. Few randomized trials have evaluated the efficacy of worksite diabetes prevention programs. This study evaluated the efficacy of a worksite lifestyle intervention on metabolic and behavioral risk factors compared with usual care. A pretest-posttest control group design with 3-month follow-up was used. Participants with prediabetes were recruited from a university worksite and randomized to receive a 16-week lifestyle intervention (n = 35) or usual care (n = 34). Participants were evaluated at baseline, postintervention, and 3-month follow-up. Dietary intake was measured by a food frequency questionnaire and level of physical activity by accelerometers. Repeated measures analysis of variance compared the change in outcomes between and within groups. Mean (standard error [SE]) weight loss was greater in the intervention (-5.5% [0.6%]) than in the control (-0.4% [0.5%]) group (P < .001) postintervention and was sustained at 3-month follow-up (P < .001). Mean (SE) reductions in fasting glucose were greater in the intervention (-8.6 [1.6] mg/dL) than in the control (-3.7 [1.6] mg/dL) group (P = .02) postintervention; both groups had significant glucose reductions at 3-month follow-up (P < .001). In the intervention group, the intake of total energy and the percentage of energy from all fats, saturated fats, and trans fats decreased, and the intake of dietary fiber increased (all P < .01) postintervention. The worksite intervention improved metabolic and behavioral risk factors among employees with prediabetes. The long-term impact on diabetes prevention and program sustainability warrant further investigation.

Thermoelectric property measurements with computer controlled systems

NASA Technical Reports Server (NTRS)

Chmielewski, A. B.; Wood, C.

1984-01-01

A joint JPL-NASA program to develop an automated system to measure the thermoelectric properties of newly developed materials is described. Consideration is given to the difficulties created by signal drift in measurements of Hall voltage and the Large Delta T Seebeck coefficient. The benefits of a computerized system were examined with respect to error reduction and time savings for human operators. It is shown that the time required to measure Hall voltage can be reduced by a factor of 10 when a computer is used to fit a curve to the ratio of the measured signal and its standard deviation. The accuracy of measurements of the Large Delta T Seebeck coefficient and thermal diffusivity was also enhanced by the use of computers.

Virtual reality and medicine--from the cockpit to the operating room: are we there yet?

PubMed

Saied, Nahel

2005-01-01

Teaching medicine to medical students, physicians in training and nurses is a challenging task that has remained unchanged for decades. The airline industry has achieved a great deal of safety and quality in a technically challenging environment. Many believe that their outstanding achievement is due to team training and crew resource management using simulators and dedicated training programs. Many experts in the medical profession believe that adopting the same strategies in teaching medical students and trainees could achieve significant reductions in medical errors and improve the quality of patient care. This article explores the role of teaching medicine using virtual reality in a multitude of medical specialties and outlines the use of simulation training at Saint Louis University.

Improving treatment plan evaluation with automation

PubMed Central

Covington, Elizabeth L.; Chen, Xiaoping; Younge, Kelly C.; Lee, Choonik; Matuszak, Martha M.; Kessler, Marc L.; Keranen, Wayne; Acosta, Eduardo; Dougherty, Ashley M.; Filpansick, Stephanie E.

2016-01-01

The goal of this work is to evaluate the effectiveness of Plan‐Checker Tool (PCT) which was created to improve first‐time plan quality, reduce patient delays, increase the efficiency of our electronic workflow, and standardize and automate the physics plan review in the treatment planning system (TPS). PCT uses an application programming interface to check and compare data from the TPS and treatment management system (TMS). PCT includes a comprehensive checklist of automated and manual checks that are documented when performed by the user as part of a plan readiness check for treatment. Prior to and during PCT development, errors identified during the physics review and causes of patient treatment start delays were tracked to prioritize which checks should be automated. Nineteen of 33 checklist items were automated, with data extracted with PCT. There was a 60% reduction in the number of patient delays in the six months after PCT release. PCT was successfully implemented for use on all external beam treatment plans in our clinic. While the number of errors found during the physics check did not decrease, automation of checks increased visibility of errors during the physics check, which led to decreased patient delays. The methods used here can be applied to any TMS and TPS that allows queries of the database. PACS number(s): 87.55.‐x, 87.55.N‐, 87.55.Qr, 87.55.tm, 89.20.Bb PMID:27929478

Achieving High Reliability in Histology:  An Improvement Series to Reduce Errors.

PubMed

Heher, Yael K; Chen, Yigu; Pyatibrat, Sergey; Yoon, Edward; Goldsmith, Jeffrey D; Sands, Kenneth E

2016-11-01

Despite sweeping medical advances in other fields, histology processes have by and large remained constant over the past 175 years. Patient label identification errors are a known liability in the laboratory and can be devastating, resulting in incorrect diagnoses and inappropriate treatment. The objective of this study was to identify vulnerable steps in the histology workflow and reduce the frequency of labeling errors (LEs). In this 36-month study period, a numerical step key (SK) was developed to capture LEs. The two most prevalent root causes were targeted for Lean workflow redesign: manual slide printing and microtome cutting. The numbers and rates of LEs before and after interventions were compared to evaluate the effectiveness of interventions. Following the adoption of a barcode-enabled laboratory information system, the error rate decreased from a baseline of 1.03% (794 errors in 76,958 cases) to 0.28% (107 errors in 37,880 cases). After the implementation of an innovative ice tool box, allowing single-piece workflow for histology microtome cutting, the rate came down to 0.22% (119 errors in 54,342 cases). The study pointed out the importance of tracking and understanding LEs by using a simple numerical SK and quantified the effectiveness of two customized Lean interventions. Overall, a 78.64% reduction in LEs and a 35.28% reduction in time spent on rework have been observed since the study began. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Impact of pharmacy technician-centered medication reconciliation on optimization of antiretroviral therapy and opportunistic infection prophylaxis in hospitalized patients with HIV/AIDS.

PubMed

Siemianowski, Laura A; Sen, Sanchita; George, Jomy M

2013-08-01

This study aimed to examine the role of a pharmacy technician-centered medication reconciliation (PTMR) program in optimization of medication therapy in hospitalized patients with HIV/AIDS. A chart review was conducted for all inpatients that had a medication reconciliation performed by the PTMR program. Adult patients with HIV and antiretroviral therapy (ART) and/or the opportunistic infection (OI) prophylaxis listed on the medication reconciliation form were included. The primary objective is to describe the (1) number and types of medication errors and (2) the percentage of patients who received appropriate ART. The secondary objective is a comparison of the number of medication errors between standard mediation reconciliation and a pharmacy-led program. In the PTMR period, 55 admissions were evaluated. In all, 50% of the patients received appropriate ART. In 27of the 55 admissions, there were 49 combined ART and OI-related errors. The most common ART-related errors were drug-drug interactions. The incidence of ART-related medication errors that included drug-drug interactions and renal dosing adjustments were similar between the pre-PTMR and PTMR groups (P = .0868). Of the 49 errors in the PTMR group, 18 were intervened by a medication reconciliation pharmacist. A PTMR program has a positive impact on optimizing ART and OI prophylaxis in patients with HIV/AIDS.

Cost effectiveness of the US Geological Survey stream-gaging program in Alabama

USGS Publications Warehouse

Jeffcoat, H.H.

1987-01-01

A study of the cost effectiveness of the stream gaging program in Alabama identified data uses and funding sources for 72 surface water stations (including dam stations, slope stations, and continuous-velocity stations) operated by the U.S. Geological Survey in Alabama with a budget of $393,600. Of these , 58 gaging stations were used in all phases of the analysis at a funding level of $328,380. For the current policy of operation of the 58-station program, the average standard error of estimation of instantaneous discharge is 29.3%. This overall level of accuracy can be maintained with a budget of $319,800 by optimizing routes and implementing some policy changes. The maximum budget considered in the analysis was $361,200, which gave an average standard error of estimation of 20.6%. The minimum budget considered was $299,360, with an average standard error of estimation of 36.5%. The study indicates that a major source of error in the stream gaging records is lost or missing data that are the result of streamside equipment failure. If perfect equipment were available, the standard error in estimating instantaneous discharge under the current program and budget could be reduced to 18.6%. This can also be interpreted to mean that the streamflow data records have a standard error of this magnitude during times when the equipment is operating properly. (Author 's abstract)

Climate change air toxic co-reduction in the context of macroeconomic modelling.

PubMed

Crawford-Brown, Douglas; Chen, Pi-Cheng; Shi, Hsiu-Ching; Chao, Chia-Wei

2013-08-15

This paper examines the health implications of global PM reduction accompanying greenhouse gas emissions reductions in the 180 national economies of the global macroeconomy. A human health effects module based on empirical data on GHG emissions, PM emissions, background PM concentrations, source apportionment and human health risk coefficients is used to estimate reductions in morbidity and mortality from PM exposures globally as co-reduction of GHG reductions. These results are compared against the "fuzzy bright line" that often underlies regulatory decisions for environmental toxics, and demonstrate that the risk reduction through PM reduction would usually be considered justified in traditional risk-based decisions for environmental toxics. It is shown that this risk reduction can be on the order of more than 4 × 10(-3) excess lifetime mortality risk, with global annual cost savings of slightly more than $10B, when uniform GHG reduction measures across all sectors of the economy form the basis for climate policy ($2.2B if only Annex I nations reduce). Consideration of co-reduction of PM-10 within a climate policy framework harmonized with other environmental policies can therefore be an effective driver of climate policy. An error analysis comparing results of the current model against those of significantly more spatially resolved models at city and national scales indicates errors caused by the low spatial resolution of the global model used here may be on the order of a factor of 2. Copyright © 2013 Elsevier Ltd. All rights reserved.

The effects of errors on children's performance on a circle-ellipse discrimination.

PubMed

Stoddard, L T; Sidman, M

1967-05-01

Children first learned by means of a teaching program to discriminate a circle from relatively flat ellipses. Children in the control group then proceeded into a program which gradually reduced the difference between the circle and the ellipses. They advanced to a finer discrimination when they made a correct choice, and reversed to an easier discrimination after making errors ("backup" procedure). The children made relatively few errors until they approached the region of their difference threshold (empirically determined under the conditions described). When they could no longer discriminate the forms, they learned other bases for responding that could be classified as specifiable error patterns. Children in the experimental group, having learned the preliminary circle-ellipse discrimination, were started at the upper end of the ellipse series, where it was impossible for them to discriminate the forms. The backup procedure returned them to an easier discrimination after they made errors. They made many errors and reversed down through the ellipse series. Eventually, most of the children reached a point in the ellipse series where they abandoned their systematic errors and began to make correct first choices; then they advanced upward through the program. All of the children advanced to ellipse sizes that were much larger than the ellipse size at the point of their furthest descent.

How to Create Automatically Graded Spreadsheets for Statistics Courses

ERIC Educational Resources Information Center

LoSchiavo, Frank M.

2016-01-01

Instructors often use spreadsheet software (e.g., Microsoft Excel) in their statistics courses so that students can gain experience conducting computerized analyses. Unfortunately, students tend to make several predictable errors when programming spreadsheets. Without immediate feedback, programming errors are likely to go undetected, and as a…

Quantum Error Correction with Biased Noise

NASA Astrophysics Data System (ADS)

Brooks, Peter

Quantum computing offers powerful new techniques for speeding up the calculation of many classically intractable problems. Quantum algorithms can allow for the efficient simulation of physical systems, with applications to basic research, chemical modeling, and drug discovery; other algorithms have important implications for cryptography and internet security. At the same time, building a quantum computer is a daunting task, requiring the coherent manipulation of systems with many quantum degrees of freedom while preventing environmental noise from interacting too strongly with the system. Fortunately, we know that, under reasonable assumptions, we can use the techniques of quantum error correction and fault tolerance to achieve an arbitrary reduction in the noise level. In this thesis, we look at how additional information about the structure of noise, or "noise bias," can improve or alter the performance of techniques in quantum error correction and fault tolerance. In Chapter 2, we explore the possibility of designing certain quantum gates to be extremely robust with respect to errors in their operation. This naturally leads to structured noise where certain gates can be implemented in a protected manner, allowing the user to focus their protection on the noisier unprotected operations. In Chapter 3, we examine how to tailor error-correcting codes and fault-tolerant quantum circuits in the presence of dephasing biased noise, where dephasing errors are far more common than bit-flip errors. By using an appropriately asymmetric code, we demonstrate the ability to improve the amount of error reduction and decrease the physical resources required for error correction. In Chapter 4, we analyze a variety of protocols for distilling magic states, which enable universal quantum computation, in the presence of faulty Clifford operations. Here again there is a hierarchy of noise levels, with a fixed error rate for faulty gates, and a second rate for errors in the distilled states which decreases as the states are distilled to better quality. The interplay of of these different rates sets limits on the achievable distillation and how quickly states converge to that limit.

42 CFR 3.552 - Harmless error.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Harmless error. 3.552 Section 3.552 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS PATIENT SAFETY ORGANIZATIONS AND PATIENT SAFETY WORK PRODUCT Enforcement Program § 3.552 Harmless error. No error in either the...

Round-off error in long-term orbital integrations using multistep methods

NASA Technical Reports Server (NTRS)

Quinlan, Gerald D.

1994-01-01

Techniques for reducing roundoff error are compared by testing them on high-order Stormer and summetric multistep methods. The best technique for most applications is to write the equation in summed, function-evaluation form and to store the coefficients as rational numbers. A larger error reduction can be achieved by writing the equation in backward-difference form and performing some of the additions in extended precision, but this entails a larger central processing unit (cpu) cost.

Applying integrals of motion to the numerical solution of differential equations

NASA Technical Reports Server (NTRS)

Vezewski, D. J.

1980-01-01

A method is developed for using the integrals of systems of nonlinear, ordinary, differential equations in a numerical integration process to control the local errors in these integrals and reduce the global errors of the solution. The method is general and can be applied to either scalar or vector integrals. A number of example problems, with accompanying numerical results, are used to verify the analysis and support the conjecture of global error reduction.

Applying integrals of motion to the numerical solution of differential equations

NASA Technical Reports Server (NTRS)

Jezewski, D. J.

1979-01-01

A method is developed for using the integrals of systems of nonlinear, ordinary differential equations in a numerical integration process to control the local errors in these integrals and reduce the global errors of the solution. The method is general and can be applied to either scaler or vector integrals. A number of example problems, with accompanying numerical results, are used to verify the analysis and support the conjecture of global error reduction.

Classification and reduction of pilot error

NASA Technical Reports Server (NTRS)

Rogers, W. H.; Logan, A. L.; Boley, G. D.

1989-01-01

Human error is a primary or contributing factor in about two-thirds of commercial aviation accidents worldwide. With the ultimate goal of reducing pilot error accidents, this contract effort is aimed at understanding the factors underlying error events and reducing the probability of certain types of errors by modifying underlying factors such as flight deck design and procedures. A review of the literature relevant to error classification was conducted. Classification includes categorizing types of errors, the information processing mechanisms and factors underlying them, and identifying factor-mechanism-error relationships. The classification scheme developed by Jens Rasmussen was adopted because it provided a comprehensive yet basic error classification shell or structure that could easily accommodate addition of details on domain-specific factors. For these purposes, factors specific to the aviation environment were incorporated. Hypotheses concerning the relationship of a small number of underlying factors, information processing mechanisms, and error types types identified in the classification scheme were formulated. ASRS data were reviewed and a simulation experiment was performed to evaluate and quantify the hypotheses.

Quantifying the impact of material-model error on macroscale quantities-of-interest using multiscale a posteriori error-estimation techniques

DOE PAGES

Brown, Judith A.; Bishop, Joseph E.

2016-07-20

An a posteriori error-estimation framework is introduced to quantify and reduce modeling errors resulting from approximating complex mesoscale material behavior with a simpler macroscale model. Such errors may be prevalent when modeling welds and additively manufactured structures, where spatial variations and material textures may be present in the microstructure. We consider a case where a <100> fiber texture develops in the longitudinal scanning direction of a weld. Transversely isotropic elastic properties are obtained through homogenization of a microstructural model with this texture and are considered the reference weld properties within the error-estimation framework. Conversely, isotropic elastic properties are considered approximatemore » weld properties since they contain no representation of texture. Errors introduced by using isotropic material properties to represent a weld are assessed through a quantified error bound in the elastic regime. Lastly, an adaptive error reduction scheme is used to determine the optimal spatial variation of the isotropic weld properties to reduce the error bound.« less

Low-noise, high-strength, spiral-bevel gears for helicopter transmissions

NASA Technical Reports Server (NTRS)

Lewicki, David G.; Handschuh, Robert F.; Henry, Zachary S.; Litvin, Faydor L.

1993-01-01

Improvements in spiral-bevel gear design were investigated to support the Army/NASA Advanced Rotorcraft Transmission program. Program objectives were to reduce weight by 25 percent, reduce noise by 10 dB, and increase life to 5000 hr mean-time-between-removal. To help meet these goals, advanced-design spiral-bevel gears were tested in an OH-58D helicopter transmission using the NASA 500-hp Helicopter Transmission Test Stand. Three different gear designs tested included: (1) the current design of the OH-58D transmission except gear material X-53 instead of AISI 9310; (2) a higher-strength design the same as the current but with a full fillet radius to reduce gear tooth bending stress (and thus, weight); and (3) a lower-noise design the same as the high-strength but with modified tooth geometry to reduce transmission error and noise. Noise, vibration, and tooth strain tests were performed and significant gear stress and noise reductions were achieved.

The Mechanics of Atmospheric Systems Derived Through Vertical and Horizontal Analysis of Parametric Data

NASA Technical Reports Server (NTRS)

Turner, R. E.

1977-01-01

For 36 hours during April 1975, an atmospheric variability experiment was conducted. This research effort supported an observational program in which rawinsonde data, radar data, and satellite data were collected from a network of 42 stations east of the Rocky Mountains at intervals of 3 hours. This program presents data with a high degree of time resolution over a spatially and temporally extensive network. Reduction of the experiment data is intended primarily as a documentation of the checking and processing of the data and should be useful to prospective users. Various flow diagrams of the data processing procedures are described, and a complete summary of the formulas used in the data processing is provided. A wind computation scheme designed to extract as much detailed wind information as possible from the unique experiment data set is discussed. The accuracy of the thermodynamic and wind data were estimated. Errors in the thermodynamic and wind data are given.

Error Prevention Aid

NASA Technical Reports Server (NTRS)

1987-01-01

In a complex computer environment there is ample opportunity for error, a mistake by a programmer, or a software-induced undesirable side effect. In insurance, errors can cost a company heavily, so protection against inadvertent change is a must for the efficient firm. The data processing center at Transport Life Insurance Company has taken a step to guard against accidental changes by adopting a software package called EQNINT (Equations Interpreter Program). EQNINT cross checks the basic formulas in a program against the formulas that make up the major production system. EQNINT assures that formulas are coded correctly and helps catch errors before they affect the customer service or its profitability.

A geometricla error in some Computer Programs based on the Aki-Christofferson-Husebye (ACH) Method of Teleseismic Tomography

USGS Publications Warehouse

Julian, B.R.; Evans, J.R.; Pritchard, M.J.; Foulger, G.R.

2000-01-01

Some computer programs based on the Aki-Christofferson-Husebye (ACH) method of teleseismic tomography contain an error caused by identifying local grid directions with azimuths on the spherical Earth. This error, which is most severe in high latitudes, introduces systematic errors into computed ray paths and distorts inferred Earth models. It is best dealt with by explicity correcting for the difference between true and grid directions. Methods for computing these directions are presented in this article and are likely to be useful in many other kinds of regional geophysical studies that use Cartesian coordinates and flat-earth approximations.

Measuring quality in anatomic pathology.

PubMed

Raab, Stephen S; Grzybicki, Dana Marie

2008-06-01

This article focuses mainly on diagnostic accuracy in measuring quality in anatomic pathology, noting that measuring any quality metric is complex and demanding. The authors discuss standardization and its variability within and across areas of care delivery and efforts involving defining and measuring error to achieve pathology quality and patient safety. They propose that data linking error to patient outcome are critical for developing quality improvement initiatives targeting errors that cause patient harm in addition to using methods of root cause analysis, beyond those traditionally used in cytologic-histologic correlation, to assist in the development of error reduction and quality improvement plans.

Mindful Reading: Mindfulness Meditation Helps Keep Readers with Dyslexia and ADHD on the Lexical Track.

PubMed

Tarrasch, Ricardo; Berman, Zohar; Friedmann, Naama

2016-01-01

This study explored the effects of a Mindfulness-Based Stress Reduction (MBSR) intervention on reading, attention, and psychological well-being among people with developmental dyslexia and/or attention deficits. Various types of dyslexia exist, characterized by different error types. We examined a question that has not been tested so far: which types of errors (and dyslexias) are affected by MBSR training. To do so, we tested, using an extensive battery of reading tests, whether each participant had dyslexia, and which errors types s/he makes, and then compared the rate of each error type before and after the MBSR workshop. We used a similar approach to attention disorders: we evaluated the participants' sustained, selective, executive, and orienting of attention to assess whether they had attention-disorders, and if so, which functions were impaired. We then evaluated the effect of MBSR on each of the attention functions. Psychological measures including mindfulness, stress, reflection and rumination, lifesatisfaction, depression, anxiety, and sleep-disturbances were also evaluated. Nineteen Hebrew-readers completed a 2-month mindfulness workshop. The results showed that whereas reading errors of letter-migrations within and between words and vowelletter errors did not decrease following the workshop, most participants made fewer reading errors in general following the workshop, with a significant reduction of 19% from their original number of errors. This decrease mainly resulted from a decrease in errors that occur due to reading via the sublexical rather than the lexical route. It seems, therefore, that mindfulness helped reading by keeping the readers on the lexical route. This improvement in reading probably resulted from improved sustained attention: the reduction in sublexical reading was significant for the dyslexic participants who also had attention deficits, and there were significant correlations between reduced reading errors and decreases in impulsivity. Following the meditation workshop, the rate of commission errors decreased, indicating decreased impulsivity, and the variation in RTs in the CPT task decreased, indicating improved sustained attention. Significant improvements were obtained in participants' mindfulness, perceived-stress, rumination, depression, state-anxiety, and sleep-disturbances. Correlations were also obtained between reading improvement and increased mindfulness following the workshop. Thus, whereas mindfulness training did not affect specific types of errors and did not improve dyslexia, it did affect the reading of adults with developmental dyslexia and ADHD, by helping them to stay on the straight path of the lexical route while reading. Thus, the reading improvement induced by mindfulness sheds light on the intricate relation between attention and reading. Mindfulness reduced impulsivity and improved sustained attention, and this, in turn, improved reading of adults with developmental dyslexia and ADHD, by helping them to read via the straight path of the lexical route.

Mindful Reading: Mindfulness Meditation Helps Keep Readers with Dyslexia and ADHD on the Lexical Track

PubMed Central

Tarrasch, Ricardo; Berman, Zohar; Friedmann, Naama

2016-01-01

This study explored the effects of a Mindfulness-Based Stress Reduction (MBSR) intervention on reading, attention, and psychological well-being among people with developmental dyslexia and/or attention deficits. Various types of dyslexia exist, characterized by different error types. We examined a question that has not been tested so far: which types of errors (and dyslexias) are affected by MBSR training. To do so, we tested, using an extensive battery of reading tests, whether each participant had dyslexia, and which errors types s/he makes, and then compared the rate of each error type before and after the MBSR workshop. We used a similar approach to attention disorders: we evaluated the participants’ sustained, selective, executive, and orienting of attention to assess whether they had attention-disorders, and if so, which functions were impaired. We then evaluated the effect of MBSR on each of the attention functions. Psychological measures including mindfulness, stress, reflection and rumination, lifesatisfaction, depression, anxiety, and sleep-disturbances were also evaluated. Nineteen Hebrew-readers completed a 2-month mindfulness workshop. The results showed that whereas reading errors of letter-migrations within and between words and vowelletter errors did not decrease following the workshop, most participants made fewer reading errors in general following the workshop, with a significant reduction of 19% from their original number of errors. This decrease mainly resulted from a decrease in errors that occur due to reading via the sublexical rather than the lexical route. It seems, therefore, that mindfulness helped reading by keeping the readers on the lexical route. This improvement in reading probably resulted from improved sustained attention: the reduction in sublexical reading was significant for the dyslexic participants who also had attention deficits, and there were significant correlations between reduced reading errors and decreases in impulsivity. Following the meditation workshop, the rate of commission errors decreased, indicating decreased impulsivity, and the variation in RTs in the CPT task decreased, indicating improved sustained attention. Significant improvements were obtained in participants’ mindfulness, perceived-stress, rumination, depression, state-anxiety, and sleep-disturbances. Correlations were also obtained between reading improvement and increased mindfulness following the workshop. Thus, whereas mindfulness training did not affect specific types of errors and did not improve dyslexia, it did affect the reading of adults with developmental dyslexia and ADHD, by helping them to stay on the straight path of the lexical route while reading. Thus, the reading improvement induced by mindfulness sheds light on the intricate relation between attention and reading. Mindfulness reduced impulsivity and improved sustained attention, and this, in turn, improved reading of adults with developmental dyslexia and ADHD, by helping them to read via the straight path of the lexical route. PMID:27242565

Minimizing Accidents and Risks in High Adventure Outdoor Pursuits.

ERIC Educational Resources Information Center

Meier, Joel

The fundamental dilemma in adventure programming is eliminating unreasonable risks to participants without also reducing levels of excitement, challenge, and stress. Most accidents are caused by a combination of unsafe conditions, unsafe acts, and error judgments. The best and only way to minimize critical human error in adventure programs is…

Precise timing correlation in telemetry recording and processing systems

NASA Technical Reports Server (NTRS)

Pickett, R. B.; Matthews, F. L.

1973-01-01

Independent PCM telemetry data signals received from missiles must be correlated to within + or - 100 microseconds for comparison with radar data. Tests have been conducted to determine RF antenna receiving system delays; delays associated with wideband analog tape recorders used in the recording, dubbing and repdocuing processes; and uncertainties associated with computer processed time tag data. Several methods used in the recording of timing are evaluated. Through the application of a special time tagging technique, the cumulative timing bias from all sources is determined and the bias removed from final data. Conclusions show that relative time differences in receiving, recording, playback and processing of two telemetry links can be accomplished with a + or - 4 microseconds accuracy. In addition, the absolute time tag error (with respect to UTC) can be reduced to less than 15 microseconds. This investigation is believed to be the first attempt to identify the individual error contributions within the telemetry system and to describe the methods of error reduction within the telemetry system and to describe the methods of error reduction and correction.

Collaborative recall of details of an emotional film.

PubMed

Wessel, Ineke; Zandstra, Anna Roos E; Hengeveld, Hester M E; Moulds, Michelle L

2015-01-01

Collaborative inhibition refers to the phenomenon that when several people work together to produce a single memory report, they typically produce fewer items than when the unique items in the individual reports of the same number of participants are combined (i.e., nominal recall). Yet, apart from this negative effect, collaboration may be beneficial in that group members remove errors from a collaborative report. Collaborative inhibition studies on memory for emotional stimuli are scarce. Therefore, the present study examined both collaborative inhibition and collaborative error reduction in the recall of the details of emotional material in a laboratory setting. Female undergraduates (n = 111) viewed a film clip of a fatal accident and subsequently engaged in either collaborative (n = 57) or individual recall (n = 54) in groups of three. The results show that, across several detail categories, collaborating groups recalled fewer details than nominal groups. However, overall, nominal recall produced more errors than collaborative recall. The present results extend earlier findings on both collaborative inhibition and error reduction to the recall of affectively laden material. These findings may have implications for the applied fields of forensic and clinical psychology.

76 FR 67315 - Supplemental Nutrition Assistance Program: Quality Control Error Tolerance Threshold

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-01

...This direct final rule is amending the Quality Control (QC) review error threshold in our regulations from $25.00 to $50.00. The purpose for raising the QC error threshold is to make permanent the temporary threshold change that was required by the American Recovery and Reinvestment Act of 2008. This change does not have an impact on the public. The QC system measures the accuracy of the eligibility system for the Supplemental Nutrition Assistance Program (SNAP).

Error bounds of adaptive dynamic programming algorithms for solving undiscounted optimal control problems.

PubMed

Liu, Derong; Li, Hongliang; Wang, Ding

2015-06-01

In this paper, we establish error bounds of adaptive dynamic programming algorithms for solving undiscounted infinite-horizon optimal control problems of discrete-time deterministic nonlinear systems. We consider approximation errors in the update equations of both value function and control policy. We utilize a new assumption instead of the contraction assumption in discounted optimal control problems. We establish the error bounds for approximate value iteration based on a new error condition. Furthermore, we also establish the error bounds for approximate policy iteration and approximate optimistic policy iteration algorithms. It is shown that the iterative approximate value function can converge to a finite neighborhood of the optimal value function under some conditions. To implement the developed algorithms, critic and action neural networks are used to approximate the value function and control policy, respectively. Finally, a simulation example is given to demonstrate the effectiveness of the developed algorithms.

Permanence analysis of a concatenated coding scheme for error control

NASA Technical Reports Server (NTRS)

Costello, D. J., Jr.; Lin, S.; Kasami, T.

1983-01-01

A concatenated coding scheme for error control in data communications is analyzed. In this scheme, the inner code is used for both error correction and detection, however, the outer code is used only for error detection. A retransmission is requested if the outer code detects the presence of errors after the inner code decoding. Probability of undetected error is derived and bounded. A particular example, proposed for the planetary program, is analyzed.

Computer program to minimize prediction error in models from experiments with 16 hypercube points and 0 to 6 center points

NASA Technical Reports Server (NTRS)

Holms, A. G.

1982-01-01

A previous report described a backward deletion procedure of model selection that was optimized for minimum prediction error and which used a multiparameter combination of the F - distribution and an order statistics distribution of Cochran's. A computer program is described that applies the previously optimized procedure to real data. The use of the program is illustrated by examples.

Greater Functional Connectivity between Reading and Error-Detection Regions Following Training with the Reading Acceleration Program in Children with Reading Difficulties

ERIC Educational Resources Information Center

Horowitz-Kraus, Tzipi; Holland, Scott K.

2015-01-01

The Reading Acceleration Program is a computerized program that improves reading and the activation of the error-detection mechanism in individuals with reading difficulty (RD) and typical readers (TRs). The current study aims to find the neural correlates for this effect in English-speaking 8-12-year-old children with RD and TRs using a…

MIMO equalization with adaptive step size for few-mode fiber transmission systems.

PubMed

van Uden, Roy G H; Okonkwo, Chigo M; Sleiffer, Vincent A J M; de Waardt, Hugo; Koonen, Antonius M J

2014-01-13

Optical multiple-input multiple-output (MIMO) transmission systems generally employ minimum mean squared error time or frequency domain equalizers. Using an experimental 3-mode dual polarization coherent transmission setup, we show that the convergence time of the MMSE time domain equalizer (TDE) and frequency domain equalizer (FDE) can be reduced by approximately 50% and 30%, respectively. The criterion used to estimate the system convergence time is the time it takes for the MIMO equalizer to reach an average output error which is within a margin of 5% of the average output error after 50,000 symbols. The convergence reduction difference between the TDE and FDE is attributed to the limited maximum step size for stable convergence of the frequency domain equalizer. The adaptive step size requires a small overhead in the form of a lookup table. It is highlighted that the convergence time reduction is achieved without sacrificing optical signal-to-noise ratio performance.

Robust estimation of thermodynamic parameters (ΔH, ΔS and ΔCp) for prediction of retention time in gas chromatography - Part II (Application).

PubMed

Claumann, Carlos Alberto; Wüst Zibetti, André; Bolzan, Ariovaldo; Machado, Ricardo A F; Pinto, Leonel Teixeira

2015-12-18

For this work, an analysis of parameter estimation for the retention factor in GC model was performed, considering two different criteria: sum of square error, and maximum error in absolute value; relevant statistics are described for each case. The main contribution of this work is the implementation of an initialization scheme (specialized) for the estimated parameters, which features fast convergence (low computational time) and is based on knowledge of the surface of the error criterion. In an application to a series of alkanes, specialized initialization resulted in significant reduction to the number of evaluations of the objective function (reducing computational time) in the parameter estimation. The obtained reduction happened between one and two orders of magnitude, compared with the simple random initialization. Copyright © 2015 Elsevier B.V. All rights reserved.

Error Detection/Correction in Collaborative Writing

ERIC Educational Resources Information Center

Pilotti, Maura; Chodorow, Martin

2009-01-01

In the present study, we examined error detection/correction during collaborative writing. Subjects were asked to identify and correct errors in two contexts: a passage written by the subject (familiar text) and a passage written by a person other than the subject (unfamiliar text). A computer program inserted errors in function words prior to the…

#2 - An Empirical Assessment of Exposure Measurement Error ...

EPA Pesticide Factsheets

Background• Differing degrees of exposure error acrosspollutants• Previous focus on quantifying and accounting forexposure error in single-pollutant models• Examine exposure errors for multiple pollutantsand provide insights on the potential for bias andattenuation of effect estimates in single and bipollutantepidemiological models The National Exposure Research Laboratory (NERL) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA mission to protect human health and the environment. HEASD research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EPA strategic plan. More specifically, our division conducts research to characterize the movement of pollutants from the source to contact with humans. Our multidisciplinary research program produces Methods, Measurements, and Models to identify relationships between and characterize processes that link source emissions, environmental concentrations, human exposures, and target-tissue dose. The impact of these tools is improved regulatory programs and policies for EPA.

[Efficacy of motivational interviewing for reducing medication errors in chronic patients over 65 years with polypharmacy: Results of a cluster randomized trial].

PubMed

Pérula de Torres, Luis Angel; Pulido Ortega, Laura; Pérula de Torres, Carlos; González Lama, Jesús; Olaya Caro, Inmaculada; Ruiz Moral, Roger

2014-10-21

To evaluate the effectiveness of an intervention based on motivational interviewing to reduce medication errors in chronic patients over 65 with polypharmacy. Cluster randomized trial that included doctors and nurses of 16 Primary Care centers and chronic patients with polypharmacy over 65 years. The professionals were assigned to the experimental or the control group using stratified randomization. Interventions consisted of training of professionals and revision of patient treatments, application of motivational interviewing in the experimental group and also the usual approach in the control group. The primary endpoint (medication error) was analyzed at individual level, and was estimated with the absolute risk reduction (ARR), relative risk reduction (RRR), number of subjects to treat (NNT) and by multiple logistic regression analysis. Thirty-two professionals were randomized (19 doctors and 13 nurses), 27 of them recruited 154 patients consecutively (13 professionals in the experimental group recruited 70 patients and 14 professionals recruited 84 patients in the control group) and completed 6 months of follow-up. The mean age of patients was 76 years (68.8% women). A decrease in the average of medication errors was observed along the period. The reduction was greater in the experimental than in the control group (F=5.109, P=.035). RRA 29% (95% confidence interval [95% CI] 15.0-43.0%), RRR 0.59 (95% CI:0.31-0.76), and NNT 3.5 (95% CI 2.3-6.8). Motivational interviewing is more efficient than the usual approach to reduce medication errors in patients over 65 with polypharmacy. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

Safety Strategies in an Academic Radiation Oncology Department and Recommendations for Action

PubMed Central

Terezakis, Stephanie A.; Pronovost, Peter; Harris, Kendra; DeWeese, Theodore; Ford, Eric

2013-01-01

Background Safety initiatives in the United States continue to work on providing guidance as to how the average practitioner might make patients safer in the face of the complex process by which radiation therapy (RT), an essential treatment used in the management of many patients with cancer, is prepared and delivered. Quality control measures can uncover certain specific errors such as machine dose mis-calibration or misalignments of the patient in the radiation treatment beam. However, they are less effective at uncovering less common errors that can occur anywhere along the treatment planning and delivery process, and even when the process is functioning as intended, errors still occur. Prioritizing Risks and Implementing Risk-Reduction Strategies Activities undertaken at the radiation oncology department at the Johns Hopkins Hospital (Baltimore) include Failure Mode and Effects Analysis (FMEA), risk-reduction interventions, and voluntary error and near-miss reporting systems. A visual process map portrayed 269 RT steps occurring among four subprocesses—including consult, simulation, treatment planning, and treatment delivery. Two FMEAs revealed 127 and 159 possible failure modes, respectively. Risk-reduction interventions for 15 “top-ranked” failure modes were implemented. Since the error and near-miss reporting system’s implementation in the department in 2007, 253 events have been logged. However, the system may be insufficient for radiation oncology, for which a greater level of practice-specific information is required to fully understand each event. Conclusions The “basic science” of radiation treatment has received considerable support and attention in developing novel therapies to benefit patients. The time has come to apply the same focus and resources to ensuring that patients safely receive the maximal benefits possible. PMID:21819027

Bell Helicopter Advanced Rotocraft Transmission (ART) program

NASA Technical Reports Server (NTRS)

Henry, Zachary S.

1995-01-01

Future rotorcraft transmissions require key emerging material and component technologies using advanced and innovative design practices in order to meet the requirements for a reduced weight to power ratio, a decreased noise level, and a substantially increased reliability. The specific goals for the future rotorcraft transmission when compared with a current state-of-the-art transmission (SOAT) are: (1) a 25 percent weight reduction; (2) a 10 dB reduction in the transmitted noise level; and (3) a system reliability of 5000 hours mean-time-between-removal (MTBR) for the transmission. This report summarizes the work conducted by Bell Helicopter Textron, Inc. to achieve these goals under the Advanced Rotorcraft Transmission (ART) program from 1988 to 1995. The reference aircraft selected by BHTI for the ART program was the Tactical Tiltrotor which is a 17,000 lb gross weight aircraft. A tradeoff study was conducted comparing the ART with a Selected SOAT. The results showed the ART to be 29 percent lighter and up to 13 dB quieter with a calculated MTBR in excess of 5000 hours. The results of the following high risk component and material tests are also presented: (1) sequential meshing high contact ratio planetary with cantilevered support posts; (2) thin dense chrome plated M50 NiL double row spherical roller planetary bearings; (3) reduced kinematic error and increased bending strength spiral bevel gears; (4) high temperature WE43 magnesium housing evaluation and coupon corrosion tests; (5) flexure fatigue tests of precision forged coupons simulating precision forged gear teeth; and (6) flexure fatigue tests of plasma carburized coupons simulating plasma carburized gear teeth.

Breaking Computational Barriers: Real-time Analysis and Optimization with Large-scale Nonlinear Models via Model Reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carlberg, Kevin Thomas; Drohmann, Martin; Tuminaro, Raymond S.

2014-10-01

Model reduction for dynamical systems is a promising approach for reducing the computational cost of large-scale physics-based simulations to enable high-fidelity models to be used in many- query (e.g., Bayesian inference) and near-real-time (e.g., fast-turnaround simulation) contexts. While model reduction works well for specialized problems such as linear time-invariant systems, it is much more difficult to obtain accurate, stable, and efficient reduced-order models (ROMs) for systems with general nonlinearities. This report describes several advances that enable nonlinear reduced-order models (ROMs) to be deployed in a variety of time-critical settings. First, we present an error bound for the Gauss-Newton with Approximatedmore » Tensors (GNAT) nonlinear model reduction technique. This bound allows the state-space error for the GNAT method to be quantified when applied with the backward Euler time-integration scheme. Second, we present a methodology for preserving classical Lagrangian structure in nonlinear model reduction. This technique guarantees that important properties--such as energy conservation and symplectic time-evolution maps--are preserved when performing model reduction for models described by a Lagrangian formalism (e.g., molecular dynamics, structural dynamics). Third, we present a novel technique for decreasing the temporal complexity --defined as the number of Newton-like iterations performed over the course of the simulation--by exploiting time-domain data. Fourth, we describe a novel method for refining projection-based reduced-order models a posteriori using a goal-oriented framework similar to mesh-adaptive h -refinement in finite elements. The technique allows the ROM to generate arbitrarily accurate solutions, thereby providing the ROM with a 'failsafe' mechanism in the event of insufficient training data. Finally, we present the reduced-order model error surrogate (ROMES) method for statistically quantifying reduced- order-model errors. This enables ROMs to be rigorously incorporated in uncertainty-quantification settings, as the error model can be treated as a source of epistemic uncertainty. This work was completed as part of a Truman Fellowship appointment. We note that much additional work was performed as part of the Fellowship. One salient project is the development of the Trilinos-based model-reduction software module Razor , which is currently bundled with the Albany PDE code and currently allows nonlinear reduced-order models to be constructed for any application supported in Albany. Other important projects include the following: 1. ROMES-equipped ROMs for Bayesian inference: K. Carlberg, M. Drohmann, F. Lu (Lawrence Berkeley National Laboratory), M. Morzfeld (Lawrence Berkeley National Laboratory). 2. ROM-enabled Krylov-subspace recycling: K. Carlberg, V. Forstall (University of Maryland), P. Tsuji, R. Tuminaro. 3. A pseudo balanced POD method using only dual snapshots: K. Carlberg, M. Sarovar. 4. An analysis of discrete v. continuous optimality in nonlinear model reduction: K. Carlberg, M. Barone, H. Antil (George Mason University). Journal articles for these projects are in progress at the time of this writing.« less

Certified dual-corrected radiation patterns of phased antenna arrays by offline–online order reduction of finite-element models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sommer, A., E-mail: a.sommer@lte.uni-saarland.de; Farle, O., E-mail: o.farle@lte.uni-saarland.de; Dyczij-Edlinger, R., E-mail: edlinger@lte.uni-saarland.de

2015-10-15

This paper presents a fast numerical method for computing certified far-field patterns of phased antenna arrays over broad frequency bands as well as wide ranges of steering and look angles. The proposed scheme combines finite-element analysis, dual-corrected model-order reduction, and empirical interpolation. To assure the reliability of the results, improved a posteriori error bounds for the radiated power and directive gain are derived. Both the reduced-order model and the error-bounds algorithm feature offline–online decomposition. A real-world example is provided to demonstrate the efficiency and accuracy of the suggested approach.

The effect of multi-channel wide dynamic range compression, noise reduction, and the directional microphone on horizontal localization performance in hearing aid wearers.

PubMed

Keidser, Gitte; Rohrseitz, Kristin; Dillon, Harvey; Hamacher, Volkmar; Carter, Lyndal; Rass, Uwe; Convery, Elizabeth

2006-10-01

This study examined the effect that signal processing strategies used in modern hearing aids, such as multi-channel WDRC, noise reduction, and directional microphones have on interaural difference cues and horizontal localization performance relative to linear, time-invariant amplification. Twelve participants were bilaterally fitted with BTE devices. Horizontal localization testing using a 360 degrees loudspeaker array and broadband pulsed pink noise was performed two weeks, and two months, post-fitting. The effect of noise reduction was measured with a constant noise present at 80 degrees azimuth. Data were analysed independently in the left/right and front/back dimension and showed that of the three signal processing strategies, directional microphones had the most significant effect on horizontal localization performance and over time. Specifically, a cardioid microphone could decrease front/back errors over time, whereas left/right errors increased when different microphones were fitted to left and right ears. Front/back confusions were generally prominent. Objective measurements of interaural differences on KEMAR explained significant shifts in left/right errors. In conclusion, there is scope for improving the sense of localization in hearing aid users.

Image enhancement by spectral-error correction for dual-energy computed tomography.

PubMed

Park, Kyung-Kook; Oh, Chang-Hyun; Akay, Metin

2011-01-01

Dual-energy CT (DECT) was reintroduced recently to use the additional spectral information of X-ray attenuation and aims for accurate density measurement and material differentiation. However, the spectral information lies in the difference between low and high energy images or measurements, so that it is difficult to acquire accurate spectral information due to amplification of high pixel noise in the resulting difference image. In this work, an image enhancement technique for DECT is proposed, based on the fact that the attenuation of a higher density material decreases more rapidly as X-ray energy increases. We define as spectral error the case when a pixel pair of low and high energy images deviates far from the expected attenuation trend. After analyzing the spectral-error sources of DECT images, we propose a DECT image enhancement method, which consists of three steps: water-reference offset correction, spectral-error correction, and anti-correlated noise reduction. It is the main idea of this work that makes spectral errors distributed like random noise over the true attenuation and suppressed by the well-known anti-correlated noise reduction. The proposed method suppressed noise of liver lesions and improved contrast between liver lesions and liver parenchyma in DECT contrast-enhanced abdominal images and their two-material decomposition.

Engineering Test Report Paint Waste Reduction Fluidized Bed Process Demonstration at Letterkenny Army Depot Chambersburg, Pennsylvania

DTIC Science & Technology

1991-07-01

predicted by equation using actual chart response obtained from each calibration gas response. (Concentration of cal. gas,l Calibration error, % span • ppm...Analyzer predicted by cali- Col. gas Chart divisions equation* bration Cylinder conc., error,** Drift,***INo. ppm or % Pretest Posttest Pretest Posttest...2m ~J * Correlation coef. * qgq’jq **Analyzer ca.error, % spn (Cal. gas conc. conc. predicted ) x 1003 cal spanSpan value Acceptable limit x ɚ% of

New Methods for Improved Double Circular-Arc Helical Gears

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Lu, Jian

1997-01-01

The authors have extended the application of double circular-arc helical gears for internal gear drives. The geometry of the pinion and gear tooth surfaces has been determined. The influence of errors of alignment on the transmission errors and the shift of the bearing contact have been investigated. Application of a predesigned parabolic function for the reduction of transmission errors was proposed. Methods of grinding of the pinion-gear tooth surfaces by a disk-shaped tool and a grinding worm were proposed.

Cost-effectiveness of the Federal stream-gaging program in Virginia

USGS Publications Warehouse

Carpenter, D.H.

1985-01-01

Data uses and funding sources were identified for the 77 continuous stream gages currently being operated in Virginia by the U.S. Geological Survey with a budget of $446,000. Two stream gages were identified as not being used sufficiently to warrant continuing their operation. Operation of these stations should be considered for discontinuation. Data collected at two other stations were identified as having uses primarily related to short-term studies; these stations should also be considered for discontinuation at the end of the data collection phases of the studies. The remaining 73 stations should be kept in the program for the foreseeable future. The current policy for operation of the 77-station program requires a budget of $446,000/yr. The average standard error of estimation of streamflow records is 10.1%. It was shown that this overall level of accuracy at the 77 sites could be maintained with a budget of $430,500 if resources were redistributed among the gages. A minimum budget of $428,500 is required to operate the 77-gage program; a smaller budget would not permit proper service and maintenance of the gages and recorders. At the minimum budget, with optimized operation, the average standard error would be 10.4%. The maximum budget analyzed was $650,000, which resulted in an average standard error of 5.5%. The study indicates that a major component of error is caused by lost or missing data. If perfect equipment were available, the standard error for the current program and budget could be reduced to 7.6%. This also can be interpreted to mean that the streamflow data have a standard error of this magnitude during times when the equipment is operating properly. (Author 's abstract)

Metonymy and Reference-Point Errors in Novice Programming

ERIC Educational Resources Information Center

Miller, Craig S.

2014-01-01

When learning to program, students often mistakenly refer to an element that is structurally related to the element that they intend to reference. For example, they may indicate the attribute of an object when their intention is to reference the whole object. This paper examines these reference-point errors through the context of metonymy.…

78 FR 77399 - Basic Health Program: Proposed Federal Funding Methodology for Program Year 2015

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-23

... American Indians and Alaska Natives F. Example Application of the BHP Funding Methodology III. Collection... effectively 138 percent due to the application of a required 5 percent income disregard in determining the... correct errors in applying the methodology (such as mathematical errors). Under section 1331(d)(3)(ii) of...

Identifying sensitive areas of adaptive observations for prediction of the Kuroshio large meander using a shallow-water model

NASA Astrophysics Data System (ADS)

Zou, Guang'an; Wang, Qiang; Mu, Mu

2016-09-01

Sensitive areas for prediction of the Kuroshio large meander using a 1.5-layer, shallow-water ocean model were investigated using the conditional nonlinear optimal perturbation (CNOP) and first singular vector (FSV) methods. A series of sensitivity experiments were designed to test the sensitivity of sensitive areas within the numerical model. The following results were obtained: (1) the eff ect of initial CNOP and FSV patterns in their sensitive areas is greater than that of the same patterns in randomly selected areas, with the eff ect of the initial CNOP patterns in CNOP sensitive areas being the greatest; (2) both CNOP- and FSV-type initial errors grow more quickly than random errors; (3) the eff ect of random errors superimposed on the sensitive areas is greater than that of random errors introduced into randomly selected areas, and initial errors in the CNOP sensitive areas have greater eff ects on final forecasts. These results reveal that the sensitive areas determined using the CNOP are more sensitive than those of FSV and other randomly selected areas. In addition, ideal hindcasting experiments were conducted to examine the validity of the sensitive areas. The results indicate that reduction (or elimination) of CNOP-type errors in CNOP sensitive areas at the initial time has a greater forecast benefit than the reduction (or elimination) of FSV-type errors in FSV sensitive areas. These results suggest that the CNOP method is suitable for determining sensitive areas in the prediction of the Kuroshio large-meander path.

Daily Orthogonal Kilovoltage Imaging Using a Gantry-Mounted On-Board Imaging System Results in a Reduction in Radiation Therapy Delivery Errors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russo, Gregory A., E-mail: gregory.russo@bmc.org; Qureshi, Muhammad M.; Truong, Minh-Tam

2012-11-01

Purpose: To determine whether the use of routine image guided radiation therapy (IGRT) using pretreatment on-board imaging (OBI) with orthogonal kilovoltage X-rays reduces treatment delivery errors. Methods and Materials: A retrospective review of documented treatment delivery errors from 2003 to 2009 was performed. Following implementation of IGRT in 2007, patients received daily OBI with orthogonal kV X-rays prior to treatment. The frequency of errors in the pre- and post-IGRT time frames was compared. Treatment errors (TEs) were classified as IGRT-preventable or non-IGRT-preventable. Results: A total of 71,260 treatment fractions were delivered to 2764 patients. A total of 135 (0.19%) TEsmore » occurred in 39 (1.4%) patients (3.2% in 2003, 1.1% in 2004, 2.5% in 2005, 2% in 2006, 0.86% in 2007, 0.24% in 2008, and 0.22% in 2009). In 2007, the TE rate decreased by >50% and has remained low (P = .00007, compared to before 2007). Errors were classified as being potentially preventable with IGRT (e.g., incorrect site, patient, or isocenter) vs. not. No patients had any IGRT-preventable TEs from 2007 to 2009, whereas there were 9 from 2003 to 2006 (1 in 2003, 2 in 2004, 2 in 2005, and 4 in 2006; P = .0058) before the implementation of IGRT. Conclusions: IGRT implementation has a patient safety benefit with a significant reduction in treatment delivery errors. As such, we recommend the use of IGRT in routine practice to complement existing quality assurance measures.« less

Daily orthogonal kilovoltage imaging using a gantry-mounted on-board imaging system results in a reduction in radiation therapy delivery errors.

PubMed

Russo, Gregory A; Qureshi, Muhammad M; Truong, Minh-Tam; Hirsch, Ariel E; Orlina, Lawrence; Bohrs, Harry; Clancy, Pauline; Willins, John; Kachnic, Lisa A

2012-11-01

To determine whether the use of routine image guided radiation therapy (IGRT) using pretreatment on-board imaging (OBI) with orthogonal kilovoltage X-rays reduces treatment delivery errors. A retrospective review of documented treatment delivery errors from 2003 to 2009 was performed. Following implementation of IGRT in 2007, patients received daily OBI with orthogonal kV X-rays prior to treatment. The frequency of errors in the pre- and post-IGRT time frames was compared. Treatment errors (TEs) were classified as IGRT-preventable or non-IGRT-preventable. A total of 71,260 treatment fractions were delivered to 2764 patients. A total of 135 (0.19%) TEs occurred in 39 (1.4%) patients (3.2% in 2003, 1.1% in 2004, 2.5% in 2005, 2% in 2006, 0.86% in 2007, 0.24% in 2008, and 0.22% in 2009). In 2007, the TE rate decreased by >50% and has remained low (P = .00007, compared to before 2007). Errors were classified as being potentially preventable with IGRT (e.g., incorrect site, patient, or isocenter) vs. not. No patients had any IGRT-preventable TEs from 2007 to 2009, whereas there were 9 from 2003 to 2006 (1 in 2003, 2 in 2004, 2 in 2005, and 4 in 2006; P = .0058) before the implementation of IGRT. IGRT implementation has a patient safety benefit with a significant reduction in treatment delivery errors. As such, we recommend the use of IGRT in routine practice to complement existing quality assurance measures. Copyright © 2012 Elsevier Inc. All rights reserved.

Landsat D Thematic Mapper image dimensionality reduction and geometric correction accuracy

NASA Technical Reports Server (NTRS)

Ford, G. E.

1986-01-01

To characterize and quantify the performance of the Landsat thematic mapper (TM), techniques for dimensionality reduction by linear transformation have been studied and evaluated and the accuracy of the correction of geometric errors in TM images analyzed. Theoretical evaluations and comparisons for existing methods for the design of linear transformation for dimensionality reduction are presented. These methods include the discrete Karhunen Loeve (KL) expansion, Multiple Discriminant Analysis (MDA), Thematic Mapper (TM)-Tasseled Cap Linear Transformation and Singular Value Decomposition (SVD). A unified approach to these design problems is presented in which each method involves optimizing an objective function with respect to the linear transformation matrix. From these studies, four modified methods are proposed. They are referred to as the Space Variant Linear Transformation, the KL Transform-MDA hybrid method, and the First and Second Version of the Weighted MDA method. The modifications involve the assignment of weights to classes to achieve improvements in the class conditional probability of error for classes with high weights. Experimental evaluations of the existing and proposed methods have been performed using the six reflective bands of the TM data. It is shown that in terms of probability of classification error and the percentage of the cumulative eigenvalues, the six reflective bands of the TM data require only a three dimensional feature space. It is shown experimentally as well that for the proposed methods, the classes with high weights have improvements in class conditional probability of error estimates as expected.

Image reduction pipeline for the detection of variable sources in highly crowded fields

NASA Astrophysics Data System (ADS)

Gössl, C. A.; Riffeser, A.

2002-01-01

We present a reduction pipeline for CCD (charge-coupled device) images which was built to search for variable sources in highly crowded fields like the M 31 bulge and to handle extensive databases due to large time series. We describe all steps of the standard reduction in detail with emphasis on the realisation of per pixel error propagation: Bias correction, treatment of bad pixels, flatfielding, and filtering of cosmic rays. The problems of conservation of PSF (point spread function) and error propagation in our image alignment procedure as well as the detection algorithm for variable sources are discussed: we build difference images via image convolution with a technique called OIS (optimal image subtraction, Alard & Lupton \\cite{1998ApJ...503..325A}), proceed with an automatic detection of variable sources in noise dominated images and finally apply a PSF-fitting, relative photometry to the sources found. For the WeCAPP project (Riffeser et al. \\cite{2001A&A...0000..00R}) we achieve 3sigma detections for variable sources with an apparent brightness of e.g. m = 24.9;mag at their minimum and a variation of Delta m = 2.4;mag (or m = 21.9;mag brightness minimum and a variation of Delta m = 0.6;mag) on a background signal of 18.1;mag/arcsec2 based on a 500;s exposure with 1.5;arcsec seeing at a 1.2;m telescope. The complete per pixel error propagation allows us to give accurate errors for each measurement.

Comparison of photogrammetric and astrometric data reduction results for the wild BC-4 camera

NASA Technical Reports Server (NTRS)

Hornbarger, D. H.; Mueller, I., I.

1971-01-01

The results of astrometric and photogrammetric plate reduction techniques for a short focal length camera are compared. Several astrometric models are tested on entire and limited plate areas to analyze their ability to remove systematic errors from interpolated satellite directions using a rigorous photogrammetric reduction as a standard. Residual plots are employed to graphically illustrate the analysis. Conclusions are made as to what conditions will permit the astrometric reduction to achieve comparable accuracies to those of photogrammetric reduction when applied for short focal length ballistic cameras.

External quality-assurance results for the National Atmospheric Deposition Program/National Trends Network during 1991

USGS Publications Warehouse

Nilles, M.A.; Gordon, J.D.; Schroder, L.J.; Paulin, C.E.

1995-01-01

The U.S. Geological Survey used four programs in 1991 to provide external quality assurance for the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). An intersite-comparison program was used to evaluate onsite pH and specific-conductance determinations. The effects of routine sample handling, processing, and shipping of wet-deposition samples on analyte determinations and an estimated precision of analyte values and concentrations were evaluated in the blind-audit program. Differences between analytical results and an estimate of the analytical precision of four laboratories routinely measuring wet deposition were determined by an interlaboratory-comparison program. Overall precision estimates for the precipitation-monitoring system were determined for selected sites by a collocated-sampler program. Results of the intersite-comparison program indicated that 93 and 86 percent of the site operators met the NADP/NTN accuracy goal for pH determinations during the two intersite-comparison studies completed during 1991. The results also indicated that 96 and 97 percent of the site operators met the NADP/NTN accuracy goal for specific-conductance determinations during the two 1991 studies. The effects of routine sample handling, processing, and shipping, determined in the blind-audit program indicated significant positive bias (a=.O 1) for calcium, magnesium, sodium, potassium, chloride, nitrate, and sulfate. Significant negative bias (or=.01) was determined for hydrogen ion and specific conductance. Only ammonium determinations were not biased. A Kruskal-Wallis test indicated that there were no significant (*3t=.01) differences in analytical results from the four laboratories participating in the interlaboratory-comparison program. Results from the collocated-sampler program indicated the median relative error for cation concentration and deposition exceeded eight percent at most sites, whereas the median relative error for sample volume, sulfate, and nitrate concentration at all sites was less than four percent. The median relative error for hydrogen ion concentration and deposition ranged from 4.6 to 18.3 percent at the four sites and as indicated in previous years of the study, was inversely proportional to the acidity of the precipitation at a given site. Overall, collocated-sampling error typically was five times that of laboratory error estimates for most analytes.

Reducing visual deficits caused by refractive errors in school and preschool children: results of a pilot school program in the Andean region of Apurimac, Peru

PubMed Central

Latorre-Arteaga, Sergio; Gil-González, Diana; Enciso, Olga; Phelan, Aoife; García-Muñoz, Ángel; Kohler, Johannes

2014-01-01

Background Refractive error is defined as the inability of the eye to bring parallel rays of light into focus on the retina, resulting in nearsightedness (myopia), farsightedness (Hyperopia) or astigmatism. Uncorrected refractive error in children is associated with increased morbidity and reduced educational opportunities. Vision screening (VS) is a method for identifying children with visual impairment or eye conditions likely to lead to visual impairment. Objective To analyze the utility of vision screening conducted by teachers and to contribute to a better estimation of the prevalence of childhood refractive errors in Apurimac, Peru. Design A pilot vision screening program in preschool (Group I) and elementary school children (Group II) was conducted with the participation of 26 trained teachers. Children whose visual acuity was<6/9 [20/30] (Group I) and≤6/9 (Group II) in one or both eyes, measured with the Snellen Tumbling E chart at 6 m, were referred for a comprehensive eye exam. Specificity and positive predictive value to detect refractive error were calculated against clinical examination. Program assessment with participants was conducted to evaluate outcomes and procedures. Results A total sample of 364 children aged 3–11 were screened; 45 children were examined at Centro Oftalmológico Monseñor Enrique Pelach (COMEP) Eye Hospital. Prevalence of refractive error was 6.2% (Group I) and 6.9% (Group II); specificity of teacher vision screening was 95.8% and 93.0%, while positive predictive value was 59.1% and 47.8% for each group, respectively. Aspects highlighted to improve the program included extending training, increasing parental involvement, and helping referred children to attend the hospital. Conclusion Prevalence of refractive error in children is significant in the region. Vision screening performed by trained teachers is a valid intervention for early detection of refractive error, including screening of preschool children. Program sustainability and improvements in education and quality of life resulting from childhood vision screening require further research. PMID:24560253

Using warnings to reduce categorical false memories in younger and older adults.

PubMed

Carmichael, Anna M; Gutchess, Angela H

2016-07-01

Warnings about memory errors can reduce their incidence, although past work has largely focused on associative memory errors. The current study sought to explore whether warnings could be tailored to specifically reduce false recall of categorical information in both younger and older populations. Before encoding word pairs designed to induce categorical false memories, half of the younger and older participants were warned to avoid committing these types of memory errors. Older adults who received a warning committed fewer categorical memory errors, as well as other types of semantic memory errors, than those who did not receive a warning. In contrast, young adults' memory errors did not differ for the warning versus no-warning groups. Our findings provide evidence for the effectiveness of warnings at reducing categorical memory errors in older adults, perhaps by supporting source monitoring, reduction in reliance on gist traces, or through effective metacognitive strategies.

The effect of covariate mean differences on the standard error and confidence interval for the comparison of treatment means.

PubMed

Liu, Xiaofeng Steven

2011-05-01

The use of covariates is commonly believed to reduce the unexplained error variance and the standard error for the comparison of treatment means, but the reduction in the standard error is neither guaranteed nor uniform over different sample sizes. The covariate mean differences between the treatment conditions can inflate the standard error of the covariate-adjusted mean difference and can actually produce a larger standard error for the adjusted mean difference than that for the unadjusted mean difference. When the covariate observations are conceived of as randomly varying from one study to another, the covariate mean differences can be related to a Hotelling's T(2) . Using this Hotelling's T(2) statistic, one can always find a minimum sample size to achieve a high probability of reducing the standard error and confidence interval width for the adjusted mean difference. ©2010 The British Psychological Society.

Reduction of Errors during Practice Facilitates Fundamental Movement Skill Learning in Children with Intellectual Disabilities

ERIC Educational Resources Information Center

Capio, C. M.; Poolton, J. M.; Sit, C. H. P.; Eguia, K. F.; Masters, R. S. W.

2013-01-01

Background: Children with intellectual disabilities (ID) have been found to have inferior motor proficiencies in fundamental movement skills (FMS). This study examined the effects of training the FMS of overhand throwing by manipulating the amount of practice errors. Methods: Participants included 39 children with ID aged 4-11 years who were…

Development and validation of Aviation Causal Contributors for Error Reporting Systems (ACCERS).

PubMed

Baker, David P; Krokos, Kelley J

2007-04-01

This investigation sought to develop a reliable and valid classification system for identifying and classifying the underlying causes of pilot errors reported under the Aviation Safety Action Program (ASAP). ASAP is a voluntary safety program that air carriers may establish to study pilot and crew performance on the line. In ASAP programs, similar to the Aviation Safety Reporting System, pilots self-report incidents by filing a short text description of the event. The identification of contributors to errors is critical if organizations are to improve human performance, yet it is difficult for analysts to extract this information from text narratives. A taxonomy was needed that could be used by pilots to classify the causes of errors. After completing a thorough literature review, pilot interviews and a card-sorting task were conducted in Studies 1 and 2 to develop the initial structure of the Aviation Causal Contributors for Event Reporting Systems (ACCERS) taxonomy. The reliability and utility of ACCERS was then tested in studies 3a and 3b by having pilots independently classify the primary and secondary causes of ASAP reports. The results provided initial evidence for the internal and external validity of ACCERS. Pilots were found to demonstrate adequate levels of agreement with respect to their category classifications. ACCERS appears to be a useful system for studying human error captured under pilot ASAP reports. Future work should focus on how ACCERS is organized and whether it can be used or modified to classify human error in ASAP programs for other aviation-related job categories such as dispatchers. Potential applications of this research include systems in which individuals self-report errors and that attempt to extract and classify the causes of those events.

Article Errors in the English Writing of Saudi EFL Preparatory Year Students

ERIC Educational Resources Information Center

Alhaisoni, Eid; Gaudel, Daya Ram; Al-Zuoud, Khalid M.

2017-01-01

This study aims at providing a comprehensive account of the types of errors produced by Saudi EFL students enrolled in the preparatory year programe in their use of articles, based on the Surface Structure Taxonomies (SST) of errors. The study describes the types, frequency and sources of the definite and indefinite article errors in writing…

Simulation of the stress computation in shells

NASA Technical Reports Server (NTRS)

Salama, M.; Utku, S.

1978-01-01

A self-teaching computer program is described, whereby the stresses in thin shells can be computed with good accuracy using the best fit approach. The program is designed for use in interactive game mode to allow the structural engineer to learn about (1) the major sources of difficulties and associated errors in the computation of stresses in thin shells, (2) possible ways to reduce the errors, and (3) trade-off between computational cost and accuracy. Included are derivation of the computational approach, program description, and several examples illustrating the program usage.

Impact of a public cholesterol screening program.

PubMed

Fischer, P M; Guinan, K H; Burke, J J; Karp, W B; Richards, J W

1990-12-01

The National Cholesterol Education Program (NCEP) has endorsed physician case finding as the primary method to detect individuals with elevated cholesterol levels. Despite this recommendation, promotional and for-profit public screening programs have flourished. We surveyed participants of a mall-based cholesterol screening program 1 year after their screening. Sixty-four percent of those screened had not previously known their cholesterol levels. Those who were newly screened were less likely to benefit from this testing than the general public, since they were older (mean age, 55.3 years), more likely to be female (67.4%), and nonsmokers (88%). Screenees had excellent recall of their cholesterol level (mean absolute reporting error, 0.24 mmol/L [9 mg/dL]) and a good understanding of cholesterol as a coronary heart disease risk. Those with elevated cholesterol levels reported high distress from screening but no reduction in overall psychosocial well-being and an actual decrease in absenteeism. Only 53.7% of all who were advised to seek follow-up because of an elevated screening value had done so within the year following the screening program. However, of those with values greater than 6.2 mmol/L (240 mg/dL), 68% had sought follow-up. Many of those who participate in public screening programs have been previously tested, fall into low-benefit groups, or fail to comply with recommended follow-up. We therefore conclude that cholesterol screening programs of the type now commonly offered are unlikely to contribute greatly to the national efforts to further reduce coronary heart disease.

Multi-Level Reduced Order Modeling Equipped with Probabilistic Error Bounds

NASA Astrophysics Data System (ADS)

Abdo, Mohammad Gamal Mohammad Mostafa

This thesis develops robust reduced order modeling (ROM) techniques to achieve the needed efficiency to render feasible the use of high fidelity tools for routine engineering analyses. Markedly different from the state-of-the-art ROM techniques, our work focuses only on techniques which can quantify the credibility of the reduction which can be measured with the reduction errors upper-bounded for the envisaged range of ROM model application. Our objective is two-fold. First, further developments of ROM techniques are proposed when conventional ROM techniques are too taxing to be computationally practical. This is achieved via a multi-level ROM methodology designed to take advantage of the multi-scale modeling strategy typically employed for computationally taxing models such as those associated with the modeling of nuclear reactor behavior. Second, the discrepancies between the original model and ROM model predictions over the full range of model application conditions are upper-bounded in a probabilistic sense with high probability. ROM techniques may be classified into two broad categories: surrogate construction techniques and dimensionality reduction techniques, with the latter being the primary focus of this work. We focus on dimensionality reduction, because it offers a rigorous approach by which reduction errors can be quantified via upper-bounds that are met in a probabilistic sense. Surrogate techniques typically rely on fitting a parametric model form to the original model at a number of training points, with the residual of the fit taken as a measure of the prediction accuracy of the surrogate. This approach, however, does not generally guarantee that the surrogate model predictions at points not included in the training process will be bound by the error estimated from the fitting residual. Dimensionality reduction techniques however employ a different philosophy to render the reduction, wherein randomized snapshots of the model variables, such as the model parameters, responses, or state variables, are projected onto lower dimensional subspaces, referred to as the "active subspaces", which are selected to capture a user-defined portion of the snapshots variations. Once determined, the ROM model application involves constraining the variables to the active subspaces. In doing so, the contribution from the variables discarded components can be estimated using a fundamental theorem from random matrix theory which has its roots in Dixon's theory, developed in 1983. This theory was initially presented for linear matrix operators. The thesis extends this theorem's results to allow reduction of general smooth nonlinear operators. The result is an approach by which the adequacy of a given active subspace determined using a given set of snapshots, generated either using the full high fidelity model, or other models with lower fidelity, can be assessed, which provides insight to the analyst on the type of snapshots required to reach a reduction that can satisfy user-defined preset tolerance limits on the reduction errors. Reactor physics calculations are employed as a test bed for the proposed developments. The focus will be on reducing the effective dimensionality of the various data streams such as the cross-section data and the neutron flux. The developed methods will be applied to representative assembly level calculations, where the size of the cross-section and flux spaces are typically large, as required by downstream core calculations, in order to capture the broad range of conditions expected during reactor operation. (Abstract shortened by ProQuest.).

Error reduction by combining strapdown inertial measurement units in a baseball stitch

NASA Astrophysics Data System (ADS)

Tracy, Leah

A poor musical performance is rarely due to an inferior instrument. When a device is under performing, the temptation is to find a better device or a new technology to achieve performance objectives; however, another solution may be improving how existing technology is used through a better understanding of device characteristics, i.e., learning to play the instrument better. This thesis explores improving position and attitude estimates of inertial navigation systems (INS) through an understanding of inertial sensor errors, manipulating inertial measurement units (IMUs) to reduce that error and multisensor fusion of multiple IMUs to reduce error in a GPS denied environment.

A Matched Project Evaluation of Modern Programming Practices. Volume II. Scientific Report on the ASTROS Plan.

DTIC Science & Technology

1980-02-01

formula for predictinq the number of errors during system testing. The equation he presents is B V/ ECRIT where B is the number of 19 ’R , errors...expected, V is the volume, and ECRIT is "the mean number of elementary discriminations between potential errors in programming" (p. 85). E CRIT can also...prediction of delivered bugs is: "V VX 2 B = V/ ECRIT -3- 13,824 2.3 McCabe’s Complexity Metric Thomas McCabe (1976) defined complexity in relation to

Neural network error correction for solving coupled ordinary differential equations

NASA Technical Reports Server (NTRS)

Shelton, R. O.; Darsey, J. A.; Sumpter, B. G.; Noid, D. W.

1992-01-01

A neural network is presented to learn errors generated by a numerical algorithm for solving coupled nonlinear differential equations. The method is based on using a neural network to correctly learn the error generated by, for example, Runge-Kutta on a model molecular dynamics (MD) problem. The neural network programs used in this study were developed by NASA. Comparisons are made for training the neural network using backpropagation and a new method which was found to converge with fewer iterations. The neural net programs, the MD model and the calculations are discussed.

A Categorization of Dynamic Analyzers

NASA Technical Reports Server (NTRS)

Lujan, Michelle R.

1997-01-01

Program analysis techniques and tools are essential to the development process because of the support they provide in detecting errors and deficiencies at different phases of development. The types of information rendered through analysis includes the following: statistical measurements of code, type checks, dataflow analysis, consistency checks, test data,verification of code, and debugging information. Analyzers can be broken into two major categories: dynamic and static. Static analyzers examine programs with respect to syntax errors and structural properties., This includes gathering statistical information on program content, such as the number of lines of executable code, source lines. and cyclomatic complexity. In addition, static analyzers provide the ability to check for the consistency of programs with respect to variables. Dynamic analyzers in contrast are dependent on input and the execution of a program providing the ability to find errors that cannot be detected through the use of static analysis alone. Dynamic analysis provides information on the behavior of a program rather than on the syntax. Both types of analysis detect errors in a program, but dynamic analyzers accomplish this through run-time behavior. This paper focuses on the following broad classification of dynamic analyzers: 1) Metrics; 2) Models; and 3) Monitors. Metrics are those analyzers that provide measurement. The next category, models, captures those analyzers that present the state of the program to the user at specified points in time. The last category, monitors, checks specified code based on some criteria. The paper discusses each classification and the techniques that are included under them. In addition, the role of each technique in the software life cycle is discussed. Familiarization with the tools that measure, model and monitor programs provides a framework for understanding the program's dynamic behavior from different, perspectives through analysis of the input/output data.

"First, know thyself": cognition and error in medicine.

PubMed

Elia, Fabrizio; Aprà, Franco; Verhovez, Andrea; Crupi, Vincenzo

2016-04-01

Although error is an integral part of the world of medicine, physicians have always been little inclined to take into account their own mistakes and the extraordinary technological progress observed in the last decades does not seem to have resulted in a significant reduction in the percentage of diagnostic errors. The failure in the reduction in diagnostic errors, notwithstanding the considerable investment in human and economic resources, has paved the way to new strategies which were made available by the development of cognitive psychology, the branch of psychology that aims at understanding the mechanisms of human reasoning. This new approach led us to realize that we are not fully rational agents able to take decisions on the basis of logical and probabilistically appropriate evaluations. In us, two different and mostly independent modes of reasoning coexist: a fast or non-analytical reasoning, which tends to be largely automatic and fast-reactive, and a slow or analytical reasoning, which permits to give rationally founded answers. One of the features of the fast mode of reasoning is the employment of standardized rules, termed "heuristics." Heuristics lead physicians to correct choices in a large percentage of cases. Unfortunately, cases exist wherein the heuristic triggered fails to fit the target problem, so that the fast mode of reasoning can lead us to unreflectively perform actions exposing us and others to variable degrees of risk. Cognitive errors arise as a result of these cases. Our review illustrates how cognitive errors can cause diagnostic problems in clinical practice.

Early effects of resident work-hour restrictions on patient safety: a systematic review and plea for improved studies.

PubMed

Baldwin, Keith; Namdari, Surena; Donegan, Derek; Kamath, Atul F; Mehta, Samir

2011-01-19

since the inception of the eighty-hour work week, work hour restrictions have incited considerable debate. Work hour policies were designed to prevent medical errors and to reduce patient morbidity and mortality. It is unclear whether work hour restrictions have been helpful in medicine in general and in orthopaedic surgery specifically. This systematic review of the literature was designed to determine the success of these restrictions in terms of patient mortality, medical errors, and complications. a systematic review of the literature was performed to determine if work hour rules have improved patient and systems-based outcomes and reduced physician errors as measured by mortality, medical errors, and complications. A random effects model was utilized to determine whether patient mortality rates were improved under the new rules. the odds of patient death before implementation of the work hour rules were 1.12 (95% confidence interval, 1.07 to 1.17) times those after implementation. These differences were consistent across disciplines. The data concerning medical or surgical complications before and after the institution of the work hour rules were mixed. There was little information in these studies concerning direct medical errors. The odds of death in nonteaching cohorts were not significantly different from that in teaching cohorts. there appears to be a decrease in mortality following the institution of work hour rules. The difference seen in teaching cohorts is not significantly different from that in nonteaching cohorts. It is unclear whether this difference would have been observed even without work hour restrictions. No study has shown a reduction in mortality for orthopaedic patients in teaching cohorts that was greater than that observed in nonteaching cohorts. Because of methodological concerns and the lack of current literature linking physician fatigue and physician underperformance with patient mortality, it is unclear whether the goals of the work hour reductions have been achieved. Furthermore, because of a lack of a so-called dose-response relationship between work hour reduction and patient mortality, it is uncertain whether further reductions would be beneficial. therapeutic Level III. See Instructions to Authors for a complete description of levels of evidence.

A GPS-Based Pitot-Static Calibration Method Using Global Output-Error Optimization

NASA Technical Reports Server (NTRS)

Foster, John V.; Cunningham, Kevin

2010-01-01

Pressure-based airspeed and altitude measurements for aircraft typically require calibration of the installed system to account for pressure sensing errors such as those due to local flow field effects. In some cases, calibration is used to meet requirements such as those specified in Federal Aviation Regulation Part 25. Several methods are used for in-flight pitot-static calibration including tower fly-by, pacer aircraft, and trailing cone methods. In the 1990 s, the introduction of satellite-based positioning systems to the civilian market enabled new inflight calibration methods based on accurate ground speed measurements provided by Global Positioning Systems (GPS). Use of GPS for airspeed calibration has many advantages such as accuracy, ease of portability (e.g. hand-held) and the flexibility of operating in airspace without the limitations of test range boundaries or ground telemetry support. The current research was motivated by the need for a rapid and statistically accurate method for in-flight calibration of pitot-static systems for remotely piloted, dynamically-scaled research aircraft. Current calibration methods were deemed not practical for this application because of confined test range size and limited flight time available for each sortie. A method was developed that uses high data rate measurements of static and total pressure, and GPSbased ground speed measurements to compute the pressure errors over a range of airspeed. The novel application of this approach is the use of system identification methods that rapidly compute optimal pressure error models with defined confidence intervals in nearreal time. This method has been demonstrated in flight tests and has shown 2- bounds of approximately 0.2 kts with an order of magnitude reduction in test time over other methods. As part of this experiment, a unique database of wind measurements was acquired concurrently with the flight experiments, for the purpose of experimental validation of the optimization method. This paper describes the GPS-based pitot-static calibration method developed for the AirSTAR research test-bed operated as part of the Integrated Resilient Aircraft Controls (IRAC) project in the NASA Aviation Safety Program (AvSP). A description of the method will be provided and results from recent flight tests will be shown to illustrate the performance and advantages of this approach. Discussion of maneuver requirements and data reduction will be included as well as potential applications.

Utilization of a CRT display light pen in the design of feedback control systems

NASA Technical Reports Server (NTRS)

Thompson, J. G.; Young, K. R.

1972-01-01

A hierarchical structure of the interlinked programs was developed to provide a flexible computer-aided design tool. A graphical input technique and a data structure are considered which provide the capability of entering the control system model description into the computer in block diagram form. An information storage and retrieval system was developed to keep track of the system description, and analysis and simulation results, and to provide them to the correct routines for further manipulation or display. Error analysis and diagnostic capabilities are discussed, and a technique was developed to reduce a transfer function to a set of nested integrals suitable for digital simulation. A general, automated block diagram reduction procedure was set up to prepare the system description for the analysis routines.

Development of Methodology for Programming Autonomous Agents

NASA Technical Reports Server (NTRS)

Erol, Kutluhan; Levy, Renato; Lang, Lun

2004-01-01

A brief report discusses the rationale for, and the development of, a methodology for generating computer code for autonomous-agent-based systems. The methodology is characterized as enabling an increase in the reusability of the generated code among and within such systems, thereby making it possible to reduce the time and cost of development of the systems. The methodology is also characterized as enabling reduction of the incidence of those software errors that are attributable to the human failure to anticipate distributed behaviors caused by the software. A major conceptual problem said to be addressed in the development of the methodology was that of how to efficiently describe the interfaces between several layers of agent composition by use of a language that is both familiar to engineers and descriptive enough to describe such interfaces unambivalently

A continuous quality improvement project to reduce medication error in the emergency department.

PubMed

Lee, Sara Bc; Lee, Larry Ly; Yeung, Richard Sd; Chan, Jimmy Ts

2013-01-01

Medication errors are a common source of adverse healthcare incidents particularly in the emergency department (ED) that has a number of factors that make it prone to medication errors. This project aims to reduce medication errors and improve the health and economic outcomes of clinical care in Hong Kong ED. In 2009, a task group was formed to identify problems that potentially endanger medication safety and developed strategies to eliminate these problems. Responsible officers were assigned to look after seven error-prone areas. Strategies were proposed, discussed, endorsed and promulgated to eliminate the problems identified. A reduction of medication incidents (MI) from 16 to 6 was achieved before and after the improvement work. This project successfully established a concrete organizational structure to safeguard error-prone areas of medication safety in a sustainable manner.

Blood transfusion sampling and a greater role for error recovery.

PubMed

Oldham, Jane

Patient identification errors in pre-transfusion blood sampling ('wrong blood in tube') are a persistent area of risk. These errors can potentially result in life-threatening complications. Current measures to address root causes of incidents and near misses have not resolved this problem and there is a need to look afresh at this issue. PROJECT PURPOSE: This narrative review of the literature is part of a wider system-improvement project designed to explore and seek a better understanding of the factors that contribute to transfusion sampling error as a prerequisite to examining current and potential approaches to error reduction. A broad search of the literature was undertaken to identify themes relating to this phenomenon. KEY DISCOVERIES: Two key themes emerged from the literature. Firstly, despite multi-faceted causes of error, the consistent element is the ever-present potential for human error. Secondly, current focus on error prevention could potentially be augmented with greater attention to error recovery. Exploring ways in which clinical staff taking samples might learn how to better identify their own errors is proposed to add to current safety initiatives.

Educational intervention together with an on-line quality control program achieve recommended analytical goals for bedside blood glucose monitoring in a 1200-bed university hospital.

PubMed

Sánchez-Margalet, Víctor; Rodriguez-Oliva, Manuel; Sánchez-Pozo, Cristina; Fernández-Gallardo, María Francisca; Goberna, Raimundo

2005-01-01

Portable meters for blood glucose concentrations are used at the patients bedside, as well as by patients for self-monitoring of blood glucose. Even though most devices have important technological advances that decrease operator error, the analytical goals proposed for the performance of glucose meters have been recently changed by the American Diabetes Association (ADA) to reach <5% analytical error and <7.9% total error. We studied 80 meters throughout the Virgen Macarena Hospital and we found most devices with performance error higher than 10%. The aim of the present study was to establish a new system to control portable glucose meters together with an educational program for nurses in a 1200-bed University Hospital to achieve recommended analytical goals, so that we could improve the quality of diabetes care. We used portable glucose meters connected on-line to the laboratory after an educational program for nurses with responsibilities in point-of-care testing. We evaluated the system by assessing total error of the glucometers using high- and low-level glucose control solutions. In a period of 6 months, we collected data from 5642 control samples obtained by 14 devices (Precision PCx) directly from the control program (QC manager). The average total error for the low-level glucose control (2.77 mmol/l) was 6.3% (range 5.5-7.6%), and even lower for the high-level glucose control (16.66 mmol/l), at 4.8% (range 4.1-6.5%). In conclusion, the performance of glucose meters used in our University Hospital with more than 1000 beds not only improved after the intervention, but the meters achieved the analytical goals of the suggested ADA/National Academy of Clinical Biochemistry criteria for total error (<7.9% in the range 2.77-16.66 mmol/l glucose) and optimal total error for high glucose concentrations of <5%, which will improve the quality of care of our patients.

RACER: Effective Race Detection Using AspectJ

NASA Technical Reports Server (NTRS)

Bodden, Eric; Havelund, Klaus

2008-01-01

The limits of coding with joint constraints on detected and undetected error rates Programming errors occur frequently in large software systems, and even more so if these systems are concurrent. In the past, researchers have developed specialized programs to aid programmers detecting concurrent programming errors such as deadlocks, livelocks, starvation and data races. In this work we propose a language extension to the aspect-oriented programming language AspectJ, in the form of three new built-in pointcuts, lock(), unlock() and may be Shared(), which allow programmers to monitor program events where locks are granted or handed back, and where values are accessed that may be shared amongst multiple Java threads. We decide thread-locality using a static thread-local objects analysis developed by others. Using the three new primitive pointcuts, researchers can directly implement efficient monitoring algorithms to detect concurrent programming errors online. As an example, we expose a new algorithm which we call RACER, an adoption of the well-known ERASER algorithm to the memory model of Java. We implemented the new pointcuts as an extension to the Aspect Bench Compiler, implemented the RACER algorithm using this language extension and then applied the algorithm to the NASA K9 Rover Executive. Our experiments proved our implementation very effective. In the Rover Executive RACER finds 70 data races. Only one of these races was previously known.We further applied the algorithm to two other multi-threaded programs written by Computer Science researchers, in which we found races as well.

NASTRAN maintenance and enhancement experiences

NASA Technical Reports Server (NTRS)

Schmitz, R. P.

1975-01-01

The current capability is described which includes isoparametric elements, optimization of grid point sequencing, and eigenvalue routine. Overlay and coding errors were corrected for cyclic symmetry, transient response, and differential stiffness rigid formats. Error corrections and program enhancements are discussed along with developments scheduled for the current year and a brief description of analyses being performed using the program.

Floating-point system quantization errors in digital control systems

NASA Technical Reports Server (NTRS)

Phillips, C. L.; Vallely, D. P.

1978-01-01

This paper considers digital controllers (filters) operating in floating-point arithmetic in either open-loop or closed-loop systems. A quantization error analysis technique is developed, and is implemented by a digital computer program that is based on a digital simulation of the system. The program can be integrated into existing digital simulations of a system.

Errors in Postural Preparation Lead to Increased Choice Reaction Times for Step Initiation in Older Adults

PubMed Central

Nutt, John G.; Horak, Fay B.

2011-01-01

Background. This study asked whether older adults were more likely than younger adults to err in the initial direction of their anticipatory postural adjustment (APA) prior to a step (indicating a motor program error), whether initial motor program errors accounted for reaction time differences for step initiation, and whether initial motor program errors were linked to inhibitory failure. Methods. In a stepping task with choice reaction time and simple reaction time conditions, we measured forces under the feet to quantify APA onset and step latency and we used body kinematics to quantify forward movement of center of mass and length of first step. Results. Trials with APA errors were almost three times as common for older adults as for younger adults, and they were nine times more likely in choice reaction time trials than in simple reaction time trials. In trials with APA errors, step latency was delayed, correlation between APA onset and step latency was diminished, and forward motion of the center of mass prior to the step was increased. Participants with more APA errors tended to have worse Stroop interference scores, regardless of age. Conclusions. The results support the hypothesis that findings of slow choice reaction time step initiation in older adults are attributable to inclusion of trials with incorrect initial motor preparation and that these errors are caused by deficits in response inhibition. By extension, the results also suggest that mixing of trials with correct and incorrect initial motor preparation might explain apparent choice reaction time slowing with age in upper limb tasks. PMID:21498431

Using Contemporary Leadership Skills in Medication Safety Programs.

PubMed

Hertig, John B; Hultgren, Kyle E; Weber, Robert J

2016-04-01

The discipline of studying medication errors and implementing medication safety programs in hospitals dates to the 1970s. These initial programs to prevent errors focused only on pharmacy operation changes - and not the broad medication use system. In the late 1990s, research showed that faulty systems, and not faulty people, are responsible for errors and require a multidisciplinary approach. The 2013 ASHP Statement on the Role of the Medication Safety Leader recommended that medication safety leaders be integrated team members rather than a single point of contact. Successful medication safety programs must employ a new approach - one that embraces the skills of all health care team members and positions many leaders to improve safety. This approach requires a new set of leadership skills based on contemporary management principles, including followership, team-building, tracking and assessing progress, storytelling and communication, and cultivating innovation, all of which promote transformational change. The application of these skills in developing or changing a medication safety program is reviewed in this article.

Using Contemporary Leadership Skills in Medication Safety Programs

PubMed Central

Hertig, John B.; Hultgren, Kyle E.; Weber, Robert J.

2016-01-01

The discipline of studying medication errors and implementing medication safety programs in hospitals dates to the 1970s. These initial programs to prevent errors focused only on pharmacy operation changes – and not the broad medication use system. In the late 1990s, research showed that faulty systems, and not faulty people, are responsible for errors and require a multidisciplinary approach. The 2013 ASHP Statement on the Role of the Medication Safety Leader recommended that medication safety leaders be integrated team members rather than a single point of contact. Successful medication safety programs must employ a new approach – one that embraces the skills of all health care team members and positions many leaders to improve safety. This approach requires a new set of leadership skills based on contemporary management principles, including followership, team-building, tracking and assessing progress, storytelling and communication, and cultivating innovation, all of which promote transformational change. The application of these skills in developing or changing a medication safety program is reviewed in this article. PMID:27303083

System IDentification Programs for AirCraft (SIDPAC)

NASA Technical Reports Server (NTRS)

Morelli, Eugene A.

2002-01-01

A collection of computer programs for aircraft system identification is described and demonstrated. The programs, collectively called System IDentification Programs for AirCraft, or SIDPAC, were developed in MATLAB as m-file functions. SIDPAC has been used successfully at NASA Langley Research Center with data from many different flight test programs and wind tunnel experiments. SIDPAC includes routines for experiment design, data conditioning, data compatibility analysis, model structure determination, equation-error and output-error parameter estimation in both the time and frequency domains, real-time and recursive parameter estimation, low order equivalent system identification, estimated parameter error calculation, linear and nonlinear simulation, plotting, and 3-D visualization. An overview of SIDPAC capabilities is provided, along with a demonstration of the use of SIDPAC with real flight test data from the NASA Glenn Twin Otter aircraft. The SIDPAC software is available without charge to U.S. citizens by request to the author, contingent on the requestor completing a NASA software usage agreement.

Evaluation of the Advanced Subsonic Technology Program Noise Reduction Benefits

NASA Technical Reports Server (NTRS)

Golub, Robert A.; Rawls, John W., Jr.; Russell, James W.

2005-01-01

This report presents a detailed evaluation of the aircraft noise reduction technology concepts developed during the course of the NASA/FAA Advanced Subsonic Technology (AST) Noise Reduction Program. In 1992, NASA and the FAA initiated a cosponsored, multi-year program with the U.S. aircraft industry focused on achieving significant advances in aircraft noise reduction. The program achieved success through a systematic development and validation of noise reduction technology. Using the NASA Aircraft Noise Prediction Program, the noise reduction benefit of the technologies that reached a NASA technology readiness level of 5 or 6 were applied to each of four classes of aircraft which included a large four engine aircraft, a large twin engine aircraft, a small twin engine aircraft and a business jet. Total aircraft noise reductions resulting from the implementation of the appropriate technologies for each class of aircraft are presented and compared to the AST program goals.

Reductions in employee productivity impairment observed after implementation of web-based worksite health promotion programs.

PubMed

Silberman, Jordan; Schwartz, Steven; Giuseffi, Danielle L; Wang, Chun; Nevedal, Dana; Bedrosian, Richard

2011-12-01

To assess changes in employee productivity impairment observed after the implementation of several Web-based health promotion programs. Health risk assessments and self-report measures of productivity impairment were administered on-line to more than 43,000 participants of Web-based health promotion programs. Reductions in productivity impairment were observed after 1 month of program utilization. Productivity impairment at 90- and 180-day follow-ups also decreased relative to baseline. Improvements in employee health were associated with reductions in employee productivity impairment. The use of Web-based health promotion programs was associated with reductions in productivity impairment and improvements in employee health. After the implementation of Web-based health promotion programs, reductions in productivity impairment may be observed before reductions in direct health care costs.

Accuracy Improvement of Multi-Axis Systems Based on Laser Correction of Volumetric Geometric Errors

NASA Astrophysics Data System (ADS)

Teleshevsky, V. I.; Sokolov, V. A.; Pimushkin, Ya I.

2018-04-01

The article describes a volumetric geometric errors correction method for CNC- controlled multi-axis systems (machine-tools, CMMs etc.). The Kalman’s concept of “Control and Observation” is used. A versatile multi-function laser interferometer is used as Observer in order to measure machine’s error functions. A systematic error map of machine’s workspace is produced based on error functions measurements. The error map results into error correction strategy. The article proposes a new method of error correction strategy forming. The method is based on error distribution within machine’s workspace and a CNC-program postprocessor. The postprocessor provides minimal error values within maximal workspace zone. The results are confirmed by error correction of precision CNC machine-tools.

SU-E-T-329: Dosimetric Impact of Implementing Metal Artifact Reduction Methods and Metal Energy Deposition Kernels for Photon Dose Calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, J; Followill, D; Howell, R

2015-06-15

Purpose: To investigate two strategies for reducing dose calculation errors near metal implants: use of CT metal artifact reduction methods and implementation of metal-based energy deposition kernels in the convolution/superposition (C/S) method. Methods: Radiochromic film was used to measure the dose upstream and downstream of titanium and Cerrobend implants. To assess the dosimetric impact of metal artifact reduction methods, dose calculations were performed using baseline, uncorrected images and metal artifact reduction Methods: Philips O-MAR, GE’s monochromatic gemstone spectral imaging (GSI) using dual-energy CT, and GSI imaging with metal artifact reduction software applied (MARs).To assess the impact of metal kernels, titaniummore » and silver kernels were implemented into a commercial collapsed cone C/S algorithm. Results: The CT artifact reduction methods were more successful for titanium than Cerrobend. Interestingly, for beams traversing the metal implant, we found that errors in the dimensions of the metal in the CT images were more important for dose calculation accuracy than reduction of imaging artifacts. The MARs algorithm caused a distortion in the shape of the titanium implant that substantially worsened the calculation accuracy. In comparison to water kernel dose calculations, metal kernels resulted in better modeling of the increased backscatter dose at the upstream interface but decreased accuracy directly downstream of the metal. We also found that the success of metal kernels was dependent on dose grid size, with smaller calculation voxels giving better accuracy. Conclusion: Our study yielded mixed results, with neither the metal artifact reduction methods nor the metal kernels being globally effective at improving dose calculation accuracy. However, some successes were observed. The MARs algorithm decreased errors downstream of Cerrobend by a factor of two, and metal kernels resulted in more accurate backscatter dose upstream of metals. Thus, these two strategies do have the potential to improve accuracy for patients with metal implants in certain scenarios. This work was supported by Public Health Service grants CA 180803 and CA 10953 awarded by the National Cancer Institute, United States of Health and Human Services, and in part by Mobius Medical Systems.« less

A short note on dynamic programming in a band.

PubMed

Gibrat, Jean-François

2018-06-15

Third generation sequencing technologies generate long reads that exhibit high error rates, in particular for insertions and deletions which are usually the most difficult errors to cope with. The only exact algorithm capable of aligning sequences with insertions and deletions is a dynamic programming algorithm. In this note, for the sake of efficiency, we consider dynamic programming in a band. We show how to choose the band width in function of the long reads' error rates, thus obtaining an [Formula: see text] algorithm in space and time. We also propose a procedure to decide whether this algorithm, when applied to semi-global alignments, provides the optimal score. We suggest that dynamic programming in a band is well suited to the problem of aligning long reads between themselves and can be used as a core component of methods for obtaining a consensus sequence from the long reads alone. The function implementing the dynamic programming algorithm in a band is available, as a standalone program, at: https://forgemia.inra.fr/jean-francois.gibrat/BAND_DYN_PROG.git.

Heat conduction errors and time lag in cryogenic thermometer installations

NASA Technical Reports Server (NTRS)

Warshawsky, I.

1973-01-01

Installation practices are recommended that will increase rate of heat exchange between the thermometric sensing element and the cryogenic fluid, in addition to bringing about a reduction in the rate of undesired heat transfer to higher temperature objects. Formulas and numerical data are given that help to estimate the magnitude of heat conduction errors and of time lag in response.

A partial least squares based spectrum normalization method for uncertainty reduction for laser-induced breakdown spectroscopy measurements

NASA Astrophysics Data System (ADS)

Li, Xiongwei; Wang, Zhe; Lui, Siu-Lung; Fu, Yangting; Li, Zheng; Liu, Jianming; Ni, Weidou

2013-10-01

A bottleneck of the wide commercial application of laser-induced breakdown spectroscopy (LIBS) technology is its relatively high measurement uncertainty. A partial least squares (PLS) based normalization method was proposed to improve pulse-to-pulse measurement precision for LIBS based on our previous spectrum standardization method. The proposed model utilized multi-line spectral information of the measured element and characterized the signal fluctuations due to the variation of plasma characteristic parameters (plasma temperature, electron number density, and total number density) for signal uncertainty reduction. The model was validated by the application of copper concentration prediction in 29 brass alloy samples. The results demonstrated an improvement on both measurement precision and accuracy over the generally applied normalization as well as our previously proposed simplified spectrum standardization method. The average relative standard deviation (RSD), average of the standard error (error bar), the coefficient of determination (R2), the root-mean-square error of prediction (RMSEP), and average value of the maximum relative error (MRE) were 1.80%, 0.23%, 0.992, 1.30%, and 5.23%, respectively, while those for the generally applied spectral area normalization were 3.72%, 0.71%, 0.973, 1.98%, and 14.92%, respectively.

Software fault-tolerance by design diversity DEDIX: A tool for experiments

NASA Technical Reports Server (NTRS)

Avizienis, A.; Gunningberg, P.; Kelly, J. P. J.; Lyu, R. T.; Strigini, L.; Traverse, P. J.; Tso, K. S.; Voges, U.

1986-01-01

The use of multiple versions of a computer program, independently designed from a common specification, to reduce the effects of an error is discussed. If these versions are designed by independent programming teams, it is expected that a fault in one version will not have the same behavior as any fault in the other versions. Since the errors in the output of the versions are different and uncorrelated, it is possible to run the versions concurrently, cross-check their results at prespecified points, and mask errors. A DEsign DIversity eXperiments (DEDIX) testbed was implemented to study the influence of common mode errors which can result in a failure of the entire system. The layered design of DEDIX and its decision algorithm are described.

76 FR 70408 - Information Collection; Understanding Value Trade-Offs Regarding Fire Hazard Reduction Programs...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-14

... Regarding Fire Hazard Reduction Programs in the Wildland-Urban Interface AGENCY: Forest Service, USDA... Regarding Fire Hazard Reduction Programs in the Wildland-Urban Interface. DATES: Comments must be received... holidays. SUPPLEMENTARY INFORMATION: Title: Understanding Value Trade-offs Regarding Fire Hazard Reduction...

The PoET (Prevention of Error-Based Transfers) Project.

PubMed

Oliver, Jill; Chidwick, Paula

2017-01-01

The PoET (Prevention of Error-based Transfers) Project is one of the Ethics Quality Improvement Projects (EQIPs) taking place at William Osler Health System. This specific project is designed to reduce transfers from long-term care to hospital that are caused by legal and ethical errors related to consent, capacity and substitute decision-making. The project is currently operating in eight long-term care homes in the Central West Local Health Integration Network and has seen a 56% reduction in multiple transfers before death in hospital.

Design of a Syntax Validation Tool for Requirements Analysis Using Structured Analysis and Design Technique (SADT)

DTIC Science & Technology

1988-09-01

analysis phase of the software life cycle (16:1-1). While editing a SADT diagram, the tool should be able to check whether or not structured analysis...diag-ams are valid for the SADT’s syntax, produce error messages, do error recovery, and perform editing suggestions. Thus, this tool must have the...directed editors are editors which use the syn- tax of the programming language while editing a program. While text editors treat programs as text, syntax

Identifying inaccuracies on emergency medicine residency applications

PubMed Central

Katz, Eric D; Shockley, Lee; Kass, Lawrence; Howes, David; Tupesis, Janis P; Weaver, Christopher; Sayan, Osman R; Hogan, Victoria; Begue, Jason; Vrocher, Diamond; Frazer, Jackie; Evans, Timothy; Hern, Gene; Riviello, Ralph; Rivera, Antonio; Kinoshita, Keith; Ferguson, Edward

2005-01-01

Background Previous trials have showed a 10–30% rate of inaccuracies on applications to individual residency programs. No studies have attempted to corroborate this on a national level. Attempts by residency programs to diminish the frequency of inaccuracies on applications have not been reported. We seek to clarify the national incidence of inaccuracies on applications to emergency medicine residency programs. Methods This is a multi-center, single-blinded, randomized, cohort study of all applicants from LCME accredited schools to involved EM residency programs. Applications were randomly selected to investigate claims of AOA election, advanced degrees and publications. Errors were reported to applicants' deans and the NRMP. Results Nine residencies reviewed 493 applications (28.6% of all applicants who applied to any EM program). 56 applications (11.4%, 95%CI 8.6–14.2%) contained at least one error. Excluding "benign" errors, 9.8% (95% CI 7.2–12.4%), contained at least one error. 41% (95% CI 35.0–47.0%) of all publications contained an error. All AOA membership claims were verified, but 13.7% (95%CI 4.4–23.1%) of claimed advanced degrees were inaccurate. Inter-rater reliability of evaluations was good. Investigators were reluctant to notify applicants' dean's offices and the NRMP. Conclusion This is the largest study to date of accuracy on application for residency and the first such multi-centered trial. High rates of incorrect data were found on applications. This data will serve as a baseline for future years of the project, with emphasis on reporting inaccuracies and warning applicants of the project's goals. PMID:16105178

SIMPLIFIED CALCULATION OF SOLAR FLUX ON THE SIDE WALL OF CYLINDRICAL CAVITY SOLAR RECEIVERS

NASA Technical Reports Server (NTRS)

Bhandari, P.

1994-01-01

The Simplified Calculation of Solar Flux Distribution on the Side Wall of Cylindrical Cavity Solar Receivers program employs a simple solar flux calculation algorithm for a cylindrical cavity type solar receiver. Applications of this program include the study of solar energy, heat transfer, and space power-solar dynamics engineering. The aperture plate of the receiver is assumed to be located in the focal plane of a paraboloidal concentrator, and the geometry is assumed to be axisymmetric. The concentrator slope error is assumed to be the only surface error; it is assumed that there are no pointing or misalignment errors. Using cone optics, the contour error method is utilized to handle the slope error of the concentrator. The flux distribution on the side wall is calculated by integration of the energy incident from cones emanating from all the differential elements on the concentrator. The calculations are done for any set of dimensions and properties of the receiver and the concentrator, and account for any spillover on the aperture plate. The results of this algorithm compared excellently with those predicted by more complicated programs. Because of the utilization of axial symmetry and overall simplification, it is extremely fast. It can be easily extended to other axi-symmetric receiver geometries. The program was written in Fortran 77, compiled using a Ryan McFarland compiler, and run on an IBM PC-AT with a math coprocessor. It requires 60K of memory and has been implemented under MS-DOS 3.2.1. The program was developed in 1988.

Height-Error Analysis for the FAA-Air Force Replacement Radar Program (FARR)

DTIC Science & Technology

1991-08-01

7719 Figure 1-7 CLIMATOLOGY ERRORS BY MONWTH PERCENT FREQUENCY TABLE OF ERROR BY MONTH ERROR MONTH Col Pc IJAl IFEB )MA IA R IAY JJ’N IJUL JAUG (SEP...MONTH Col Pct IJAN IFEB IMPJ JAPR 1 MM IJUN IJUL JAUG ISEP J--T IN~ IDEC I Total ----- -- - - --------------------------.. . -.. 4...MONTH ERROR MONTH Col Pct IJAN IFEB IM4AR IAPR IMAY jJum IJU JAUG ISEP JOCT IN JDEC I Total . .- 4

Experimental Investigation of Jet Impingement Heat Transfer Using Thermochromic Liquid Crystals

NASA Technical Reports Server (NTRS)

Dempsey, Brian Paul

1997-01-01

Jet impingement cooling of a hypersonic airfoil leading edge is experimentally investigated using thermochromic liquid crystals (TLCS) to measure surface temperature. The experiment uses computer data acquisition with digital imaging of the TLCs to determine heat transfer coefficients during a transient experiment. The data reduction relies on analysis of a coupled transient conduction - convection heat transfer problem that characterizes the experiment. The recovery temperature of the jet is accounted for by running two experiments with different heating rates, thereby generating a second equation that is used to solve for the recovery temperature. The resulting solution requires a complicated numerical iteration that is handled by a computer. Because the computational data reduction method is complex, special attention is paid to error assessment. The error analysis considers random and systematic errors generated by the instrumentation along with errors generated by the approximate nature of the numerical methods. Results of the error analysis show that the experimentally determined heat transfer coefficients are accurate to within 15%. The error analysis also shows that the recovery temperature data may be in error by more than 50%. The results show that the recovery temperature data is only reliable when the recovery temperature of the jet is greater than 5 C, i.e. the jet velocity is in excess of 100 m/s. Parameters that were investigated include nozzle width, distance from the nozzle exit to the airfoil surface, and jet velocity. Heat transfer data is presented in graphical and tabular forms. An engineering analysis of hypersonic airfoil leading edge cooling is performed using the results from these experiments. Several suggestions for the improvement of the experimental technique are discussed.

Methods to Improve the Maintenance of the Earth Catalog of Satellites During Severe Solar Storms

NASA Technical Reports Server (NTRS)

Wilkin, Paul G.; Tolson, Robert H.

1998-01-01

The objective of this thesis is to investigate methods to improve the ability to maintain the inventory of orbital elements of Earth satellites during periods of atmospheric disturbance brought on by severe solar activity. Existing techniques do not account for such atmospheric dynamics, resulting in tracking errors of several seconds in predicted crossing time. Two techniques are examined to reduce of these tracking errors. First, density predicted from various atmospheric models is fit to the orbital decay rate for a number of satellites. An orbital decay model is then developed that could be used to reduce tracking errors by accounting for atmospheric changes. The second approach utilizes a Kalman filter to estimate the orbital decay rate of a satellite after every observation. The new information is used to predict the next observation. Results from the first approach demonstrated the feasibility of building an orbital decay model based on predicted atmospheric density. Correlation of atmospheric density to orbital decay was as high as 0.88. However, it is clear that contemporary: atmospheric models need further improvement in modeling density perturbations polar region brought on by solar activity. The second approach resulted in a dramatic reduction in tracking errors for certain satellites during severe solar Storms. For example, in the limited cases studied, the reduction in tracking errors ranged from 79 to 25 percent.

Water displacement leg volumetry in clinical studies - A discussion of error sources

PubMed Central

2010-01-01

Background Water displacement leg volumetry is a highly reproducible method, allowing the confirmation of efficacy of vasoactive substances. Nevertheless errors of its execution and the selection of unsuitable patients are likely to negatively affect the outcome of clinical studies in chronic venous insufficiency (CVI). Discussion Placebo controlled double-blind drug studies in CVI were searched (Cochrane Review 2005, MedLine Search until December 2007) and assessed with regard to efficacy (volume reduction of the leg), patient characteristics, and potential methodological error sources. Almost every second study reported only small drug effects (≤ 30 mL volume reduction). As the most relevant error source the conduct of volumetry was identified. Because the practical use of available equipment varies, volume differences of more than 300 mL - which is a multifold of a potential treatment effect - have been reported between consecutive measurements. Other potential error sources were insufficient patient guidance or difficulties with the transition from the Widmer CVI classification to the CEAP (Clinical Etiological Anatomical Pathophysiological) grading. Summary Patients should be properly diagnosed with CVI and selected for stable oedema and further clinical symptoms relevant for the specific study. Centres require a thorough training on the use of the volumeter and on patient guidance. Volumetry should be performed under constant conditions. The reproducibility of short term repeat measurements has to be ensured. PMID:20070899

Vision-based real-time position control of a semi-automated system for robot-assisted joint fracture surgery.

PubMed

Dagnino, Giulio; Georgilas, Ioannis; Tarassoli, Payam; Atkins, Roger; Dogramadzi, Sanja

2016-03-01

Joint fracture surgery quality can be improved by robotic system with high-accuracy and high-repeatability fracture fragment manipulation. A new real-time vision-based system for fragment manipulation during robot-assisted fracture surgery was developed and tested. The control strategy was accomplished by merging fast open-loop control with vision-based control. This two-phase process is designed to eliminate the open-loop positioning errors by closing the control loop using visual feedback provided by an optical tracking system. Evaluation of the control system accuracy was performed using robot positioning trials, and fracture reduction accuracy was tested in trials on ex vivo porcine model. The system resulted in high fracture reduction reliability with a reduction accuracy of 0.09 mm (translations) and of [Formula: see text] (rotations), maximum observed errors in the order of 0.12 mm (translations) and of [Formula: see text] (rotations), and a reduction repeatability of 0.02 mm and [Formula: see text]. The proposed vision-based system was shown to be effective and suitable for real joint fracture surgical procedures, contributing a potential improvement of their quality.

At the cross-roads: an on-road examination of driving errors at intersections.

PubMed

Young, Kristie L; Salmon, Paul M; Lenné, Michael G

2013-09-01

A significant proportion of road trauma occurs at intersections. Understanding the nature of driving errors at intersections therefore has the potential to lead to significant injury reductions. To further understand how the complexity of modern intersections shapes behaviour of these errors are compared to errors made mid-block, and the role of wider systems failures in intersection error causation is investigated in an on-road study. Twenty-five participants drove a pre-determined urban route incorporating 25 intersections. Two in-vehicle observers recorded the errors made while a range of other data was collected, including driver verbal protocols, video, driver eye glance behaviour and vehicle data (e.g., speed, braking and lane position). Participants also completed a post-trial cognitive task analysis interview. Participants were found to make 39 specific error types, with speeding violations the most common. Participants made significantly more errors at intersections compared to mid-block, with misjudgement, action and perceptual/observation errors more commonly observed at intersections. Traffic signal configuration was found to play a key role in intersection error causation, with drivers making more errors at partially signalised compared to fully signalised intersections. Copyright © 2012 Elsevier Ltd. All rights reserved.

Examples of Nonconservatism in the CARE 3 Program

NASA Technical Reports Server (NTRS)

Dotson, Kelly J.

1988-01-01

This paper presents parameter regions in the CARE 3 (Computer-Aided Reliability Estimation version 3) computer program where the program overestimates the reliability of a modeled system without warning the user. Five simple models of fault-tolerant computer systems are analyzed; and, the parameter regions where reliability is overestimated are given. The source of the error in the reliability estimates for models which incorporate transient fault occurrences was not readily apparent. However, the source of much of the error for models with permanent and intermittent faults can be attributed to the choice of values for the run-time parameters of the program.

Human errors and measurement uncertainty

NASA Astrophysics Data System (ADS)

Kuselman, Ilya; Pennecchi, Francesca

2015-04-01

Evaluating the residual risk of human errors in a measurement and testing laboratory, remaining after the error reduction by the laboratory quality system, and quantifying the consequences of this risk for the quality of the measurement/test results are discussed based on expert judgments and Monte Carlo simulations. A procedure for evaluation of the contribution of the residual risk to the measurement uncertainty budget is proposed. Examples are provided using earlier published sets of expert judgments on human errors in pH measurement of groundwater, elemental analysis of geological samples by inductively coupled plasma mass spectrometry, and multi-residue analysis of pesticides in fruits and vegetables. The human error contribution to the measurement uncertainty budget in the examples was not negligible, yet also not dominant. This was assessed as a good risk management result.

Towards a Framework for Managing Risk Associated with Technology-Induced Error.

PubMed

Borycki, Elizabeth M; Kushniruk, Andre W

2017-01-01

Health information technologies (HIT) promised to streamline and modernize healthcare processes. However, a growing body of research has indicated that if such technologies are not designed, implemented or maintained properly this may lead to an increased incidence of new types of errors which the authors have referred to as "technology-induced errors". In this paper, framework is presented that can be used to manage HIT risk. The framework considers the reduction of technology-induced errors at different stages by managing risks associated with the implementation of HIT. Frameworks that allow health information technology managers to employ proactive and preventative approaches that can be used to manage the risks associated with technology-induced errors are critical to improving HIT safety and managing risk associated with implementing new technologies.

Professional Development Processes That Promote Teacher Change: The Case of a Video-Based Program Focused on Leveraging Students' Mathematical Errors

ERIC Educational Resources Information Center

Santagata, Rossella; Bray, Wendy

2016-01-01

This study examined processes at the core of teacher professional development (PD) experiences that might positively impact teacher learning and more specifically teacher change. Four processes were considered in the context of a PD program focused on student mathematical errors: analysis of students' mathematical misconceptions as a lever for…

Using Weighted Constraints to Diagnose Errors in Logic Programming--The Case of an Ill-Defined Domain

ERIC Educational Resources Information Center

Le, Nguyen-Thinh; Menzel, Wolfgang

2009-01-01

In this paper, we introduce logic programming as a domain that exhibits some characteristics of being ill-defined. In order to diagnose student errors in such a domain, we need a means to hypothesise the student's intention, that is the strategy underlying her solution. This is achieved by weighting constraints, so that hypotheses about solution…

POOLMS: A computer program for fitting and model selection for two level factorial replication-free experiments

NASA Technical Reports Server (NTRS)

Amling, G. E.; Holms, A. G.

1973-01-01

A computer program is described that performs a statistical multiple-decision procedure called chain pooling. It uses a number of mean squares assigned to error variance that is conditioned on the relative magnitudes of the mean squares. The model selection is done according to user-specified levels of type 1 or type 2 error probabilities.

The Error Prone Model and the Basic Grants Validation Selection System. Draft Final Report.

ERIC Educational Resources Information Center

System Development Corp., Falls Church, VA.

An evaluation of existing and proposed mechanisms to ensure data accuracy for the Pell Grant program is reported, and recommendations for efficient detection of fraud and error in the program are offered. One study objective was to examine the existing system of pre-established criteria (PEC), which are validation criteria that select students on…

76 FR 52937 - Ball Bearings and Parts Thereof From France, Germany, and Italy: Final Results of Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-24

... programming and other errors in the margin calculations. Therefore, the final results are different from the... certain companies. We have corrected programming and other errors in the margins we included in the... Technologies GmbH; Italy--Schaeffler Italia S.r.l./WPB Water Pump Bearing GmbH & Co. KG/The Schaeffler Group...

Prevention of prescription errors by computerized, on-line, individual patient related surveillance of drug order entry.

PubMed

Oliven, A; Zalman, D; Shilankov, Y; Yeshurun, D; Odeh, M

2002-01-01

Computerized prescription of drugs is expected to reduce the number of many preventable drug ordering errors. In the present study we evaluated the usefullness of a computerized drug order entry (CDOE) system in reducing prescription errors. A department of internal medicine using a comprehensive CDOE, which included also patient-related drug-laboratory, drug-disease and drug-allergy on-line surveillance was compared to a similar department in which drug orders were handwritten. CDOE reduced prescription errors to 25-35%. The causes of errors remained similar, and most errors, on both departments, were associated with abnormal renal function and electrolyte balance. Residual errors remaining on the CDOE-using department were due to handwriting on the typed order, failure to feed patients' diseases, and system failures. The use of CDOE was associated with a significant reduction in mean hospital stay and in the number of changes performed in the prescription. The findings of this study both quantity the impact of comprehensive CDOE on prescription errors and delineate the causes for remaining errors.

Effectiveness of Specimen Collection Technology in the Reduction of Collection Turnaround Time and Mislabeled Specimens in Emergency, Medical-Surgical, Critical Care, and Maternal Child Health Departments.

PubMed

Saathoff, April M; MacDonald, Ryan; Krenzischek, Erundina

2018-03-01

The objective of this study was to evaluate the impact of specimen collection technology implementation featuring computerized provider order entry, positive patient identification, bedside specimen label printing, and barcode scanning on the reduction of mislabeled specimens and collection turnaround times in the emergency, medical-surgical, critical care, and maternal child health departments at a community teaching hospital. A quantitative analysis of a nonrandomized, pre-post intervention study design evaluated the statistical significance of reduction of mislabeled specimen percentages and collection turnaround times affected by the implementation of specimen collection technology. Mislabeled specimen percentages in all areas decreased from an average of 0.020% preimplementation to an average of 0.003% postimplementation, with a P < .001. Collection turnaround times longer than 60 minutes decreased after the implementation of specimen collection technology by an average of 27%, with a P < .001. Specimen collection and identification errors are a significant problem in healthcare, contributing to incorrect diagnoses, delayed care, lack of essential treatments, and patient injury or death. Collection errors can also contribute to an increased length of stay, increased healthcare costs, and decreased patient satisfaction. Specimen collection technology has structures in place to prevent collection errors and improve the overall efficiency of the specimen collection process.

Functional Independent Scaling Relation for ORR/OER Catalysts

DOE PAGES

Christensen, Rune; Hansen, Heine A.; Dickens, Colin F.; ...

2016-10-11

A widely used adsorption energy scaling relation between OH* and OOH* intermediates in the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), has previously been determined using density functional theory and shown to dictate a minimum thermodynamic overpotential for both reactions. Here, we show that the oxygen–oxygen bond in the OOH* intermediate is, however, not well described with the previously used class of exchange-correlation functionals. By quantifying and correcting the systematic error, an improved description of gaseous peroxide species versus experimental data and a reduction in calculational uncertainty is obtained. For adsorbates, we find that the systematic error largelymore » cancels the vdW interaction missing in the original determination of the scaling relation. An improved scaling relation, which is fully independent of the applied exchange–correlation functional, is obtained and found to differ by 0.1 eV from the original. Lastly, this largely confirms that, although obtained with a method suffering from systematic errors, the previously obtained scaling relation is applicable for predictions of catalytic activity.« less

Diagnosing Crime and Diagnosing Disease: Bias Reduction Strategies in the Forensic and Clinical Sciences.

PubMed

Lockhart, Joseph J; Satya-Murti, Saty

2017-11-01

Cognitive effort is an essential part of both forensic and clinical decision-making. Errors occur in both fields because the cognitive process is complex and prone to bias. We performed a selective review of full-text English language literature on cognitive bias leading to diagnostic and forensic errors. Earlier work (1970-2000) concentrated on classifying and raising bias awareness. Recently (2000-2016), the emphasis has shifted toward strategies for "debiasing." While the forensic sciences have focused on the control of misleading contextual cues, clinical debiasing efforts have relied on checklists and hypothetical scenarios. No single generally applicable and effective bias reduction strategy has emerged so far. Generalized attempts at bias elimination have not been particularly successful. It is time to shift focus to the study of errors within specific domains, and how to best communicate uncertainty in order to improve decision making on the part of both the expert and the trier-of-fact. © 2017 American Academy of Forensic Sciences.

Model Reduction for Control System Design

NASA Technical Reports Server (NTRS)

Enns, D. F.

1985-01-01

An approach and a technique for effectively obtaining reduced order mathematical models of a given large order model for the purposes of synthesis, analysis and implementation of control systems is developed. This approach involves the use of an error criterion which is the H-infinity norm of a frequency weighted error between the full and reduced order models. The weightings are chosen to take into account the purpose for which the reduced order model is intended. A previously unknown error bound in the H-infinity norm for reduced order models obtained from internally balanced realizations was obtained. This motivated further development of the balancing technique to include the frequency dependent weightings. This resulted in the frequency weighted balanced realization and a new model reduction technique. Two approaches to designing reduced order controllers were developed. The first involves reducing the order of a high order controller with an appropriate weighting. The second involves linear quadratic Gaussian synthesis based on a reduced order model obtained with an appropriate weighting.

FMEA: a model for reducing medical errors.

PubMed

Chiozza, Maria Laura; Ponzetti, Clemente

2009-06-01

Patient safety is a management issue, in view of the fact that clinical risk management has become an important part of hospital management. Failure Mode and Effect Analysis (FMEA) is a proactive technique for error detection and reduction, firstly introduced within the aerospace industry in the 1960s. Early applications in the health care industry dating back to the 1990s included critical systems in the development and manufacture of drugs and in the prevention of medication errors in hospitals. In 2008, the Technical Committee of the International Organization for Standardization (ISO), licensed a technical specification for medical laboratories suggesting FMEA as a method for prospective risk analysis of high-risk processes. Here we describe the main steps of the FMEA process and review data available on the application of this technique to laboratory medicine. A significant reduction of the risk priority number (RPN) was obtained when applying FMEA to blood cross-matching, to clinical chemistry analytes, as well as to point-of-care testing (POCT).

Development and Assessment of a Medication Safety Measurement Program in a Long-Term Care Pharmacy.

PubMed

Hertig, John B; Hultgren, Kyle E; Parks, Scott; Rondinelli, Rick

2016-02-01

Medication errors continue to be a major issue in the health care system, including in long-term care facilities. While many hospitals and health systems have developed methods to identify, track, and prevent these errors, long-term care facilities historically have not invested in these error-prevention strategies. The objective of this study was two-fold: 1) to develop a set of medication-safety process measures for dispensing in a long-term care pharmacy, and 2) to analyze the data from those measures to determine the relative safety of the process. The study was conducted at In Touch Pharmaceuticals in Valparaiso, Indiana. To assess the safety of the medication-use system, each step was documented using a comprehensive flowchart (process flow map) tool. Once completed and validated, the flowchart was used to complete a "failure modes and effects analysis" (FMEA) identifying ways a process may fail. Operational gaps found during FMEA were used to identify points of measurement. The research identified a set of eight measures as potential areas of failure; data were then collected on each one of these. More than 133,000 medication doses (opportunities for errors) were included in the study during the research time frame (April 1, 2014, and ended on June 4, 2014). Overall, there was an approximate order-entry error rate of 15.26%, with intravenous errors at 0.37%. A total of 21 errors migrated through the entire medication-use system. These 21 errors in 133,000 opportunities resulted in a final check error rate of 0.015%. A comprehensive medication-safety measurement program was designed and assessed. This study demonstrated the ability to detect medication errors in a long-term pharmacy setting, thereby making process improvements measureable. Future, larger, multi-site studies should be completed to test this measurement program.

High-Speed Jet Noise Reduction NASA Perspective

NASA Technical Reports Server (NTRS)

Huff, Dennis L.; Handy, J. (Technical Monitor)

2001-01-01

History shows that the problem of high-speed jet noise reduction is difficult to solve. the good news is that high performance military aircraft noise is dominated by a single source called 'jet noise' (commercial aircraft have several sources). The bad news is that this source has been the subject of research for the past 50 years and progress has been incremental. Major jet noise reduction has been achieved through changing the cycle of the engine to reduce the jet exit velocity. Smaller reductions have been achieved using suppression devices like mixing enhancement and acoustic liners. Significant jet noise reduction without any performance loss is probably not possible! Recent NASA Noise Reduction Research Programs include the High Speed Research Program, Advanced Subsonic Technology Noise Reduction Program, Aerospace Propulsion and Power Program - Fundamental Noise, and Quiet Aircraft Technology Program.

Medical error reduction and tort reform through private, contractually-based quality medicine societies.

PubMed

MacCourt, Duncan; Bernstein, Joseph

2009-01-01

The current medical malpractice system is broken. Many patients injured by malpractice are not compensated, whereas some patients who recover in tort have not suffered medical negligence; furthermore, the system's failures demoralize patients and physicians. But most importantly, the system perpetuates medical error because the adversarial nature of litigation induces a so-called "Culture of Silence" in physicians eager to shield themselves from liability. This silence leads to the pointless repetition of error, as the open discussion and analysis of the root causes of medical mistakes does not take place as fully as it should. In 1993, President Clinton's Task Force on National Health Care Reform considered a solution characterized by Enterprise Medical Liability (EML), Alternative Dispute Resolution (ADR), some limits on recovery for non-pecuniary damages (Caps), and offsets for collateral source recovery. Yet this list of ingredients did not include a strategy to surmount the difficulties associated with each element. Specifically, EML might be efficient, but none of the enterprises contemplated to assume responsibility, i.e., hospitals and payers, control physician behavior enough so that it would be fair to foist liability on them. Likewise, although ADR might be efficient, it will be resisted by individual litigants who perceive themselves as harmed by it. Finally, while limitations on collateral source recovery and damages might effectively reduce costs, patients and trial lawyers likely would not accept them without recompense. The task force also did not place error reduction at the center of malpractice tort reform -a logical and strategic error, in our view. In response, we propose a new system that employs the ingredients suggested by the task force but also addresses the problems with each. We also explicitly consider steps to rebuff the Culture of Silence and promote error reduction. We assert that patients would be better off with a system where physicians cede their implicit "right to remain silent", even if some injured patients will receive less than they do today. Likewise, physicians will be happier with a system that avoids blame-even if this system placed strict requirements for high quality care and disclosure of error. We therefore conceive of de facto trade between patients and physicians, a Pareto improvement, taking form via the establishment of "Societies of Quality Medicine." Physicians working within these societies would consent to onerous processes for disclosing, rectifying and preventing medical error. Patients would in turn contractually agree to assert their claims in arbitration and with limits on recovery. The role of plaintiffs' lawyers would be unchanged, but due to increased disclosure, discovery costs would diminish and the likelihood of prevailing will more than triple. This article examines the legal and policy issues surrounding the establishment of Societies of Quality Medicine, particularly the issues of contracting over liability, and outlines a means of overcoming the theoretical and practical difficulties with enterprise liability, alternative dispute resolution and the imposition of limits on recovery for non-pecuniary damages. We aim to build a welfare enhancing system that rebuffs the culture of silence and promotes error reduction, a system that is at the same time legally sound, fiscally prudent and politically possible.

Magneto-optical tracking of flexible laparoscopic ultrasound: model-based online detection and correction of magnetic tracking errors.

PubMed

Feuerstein, Marco; Reichl, Tobias; Vogel, Jakob; Traub, Joerg; Navab, Nassir

2009-06-01

Electromagnetic tracking is currently one of the most promising means of localizing flexible endoscopic instruments such as flexible laparoscopic ultrasound transducers. However, electromagnetic tracking is also susceptible to interference from ferromagnetic material, which distorts the magnetic field and leads to tracking errors. This paper presents new methods for real-time online detection and reduction of dynamic electromagnetic tracking errors when localizing a flexible laparoscopic ultrasound transducer. We use a hybrid tracking setup to combine optical tracking of the transducer shaft and electromagnetic tracking of the flexible transducer tip. A novel approach of modeling the poses of the transducer tip in relation to the transducer shaft allows us to reliably detect and significantly reduce electromagnetic tracking errors. For detecting errors of more than 5 mm, we achieved a sensitivity and specificity of 91% and 93%, respectively. Initial 3-D rms error of 6.91 mm were reduced to 3.15 mm.

42 CFR 407.32 - Prejudice to enrollment rights because of Federal Government misrepresentation, inaction, or error.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Government misrepresentation, inaction, or error. 407.32 Section 407.32 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL INSURANCE... enrollment rights because of Federal Government misrepresentation, inaction, or error. If an individual's...

42 CFR 407.32 - Prejudice to enrollment rights because of Federal Government misrepresentation, inaction, or error.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Government misrepresentation, inaction, or error. 407.32 Section 407.32 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL INSURANCE... enrollment rights because of Federal Government misrepresentation, inaction, or error. If an individual's...

Phase noise optimization in temporal phase-shifting digital holography with partial coherence light sources and its application in quantitative cell imaging.

PubMed

Remmersmann, Christian; Stürwald, Stephan; Kemper, Björn; Langehanenberg, Patrik; von Bally, Gert

2009-03-10

In temporal phase-shifting-based digital holographic microscopy, high-resolution phase contrast imaging requires optimized conditions for hologram recording and phase retrieval. To optimize the phase resolution, for the example of a variable three-step algorithm, a theoretical analysis on statistical errors, digitalization errors, uncorrelated errors, and errors due to a misaligned temporal phase shift is carried out. In a second step the theoretically predicted results are compared to the measured phase noise obtained from comparative experimental investigations with several coherent and partially coherent light sources. Finally, the applicability for noise reduction is demonstrated by quantitative phase contrast imaging of pancreas tumor cells.

Organizational safety culture and medical error reporting by Israeli nurses.

PubMed

Kagan, Ilya; Barnoy, Sivia

2013-09-01

To investigate the association between patient safety culture (PSC) and the incidence and reporting rate of medical errors by Israeli nurses. Self-administered structured questionnaires were distributed to a convenience sample of 247 registered nurses enrolled in training programs at Tel Aviv University (response rate = 91%). The questionnaire's three sections examined the incidence of medication mistakes in clinical practice, the reporting rate for these errors, and the participants' views and perceptions of the safety culture in their workplace at three levels (organizational, departmental, and individual performance). Pearson correlation coefficients, t tests, and multiple regression analysis were used to analyze the data. Most nurses encountered medical errors from a daily to a weekly basis. Six percent of the sample never reported their own errors, while half reported their own errors "rarely or sometimes." The level of PSC was positively and significantly correlated with the error reporting rate. PSC, place of birth, error incidence, and not having an academic nursing degree were significant predictors of error reporting, together explaining 28% of variance. This study confirms the influence of an organizational safety climate on readiness to report errors. Senior healthcare executives and managers can make a major impact on safety culture development by creating and promoting a vision and strategy for quality and safety and fostering their employees' motivation to implement improvement programs at the departmental and individual level. A positive, carefully designed organizational safety culture can encourage error reporting by staff and so improve patient safety. © 2013 Sigma Theta Tau International.

The Error Reporting in the ATLAS TDAQ System

NASA Astrophysics Data System (ADS)

Kolos, Serguei; Kazarov, Andrei; Papaevgeniou, Lykourgos

2015-05-01

The ATLAS Error Reporting provides a service that allows experts and shift crew to track and address errors relating to the data taking components and applications. This service, called the Error Reporting Service (ERS), gives to software applications the opportunity to collect and send comprehensive data about run-time errors, to a place where it can be intercepted in real-time by any other system component. Other ATLAS online control and monitoring tools use the ERS as one of their main inputs to address system problems in a timely manner and to improve the quality of acquired data. The actual destination of the error messages depends solely on the run-time environment, in which the online applications are operating. When an application sends information to ERS, depending on the configuration, it may end up in a local file, a database, distributed middleware which can transport it to an expert system or display it to users. Thanks to the open framework design of ERS, new information destinations can be added at any moment without touching the reporting and receiving applications. The ERS Application Program Interface (API) is provided in three programming languages used in the ATLAS online environment: C++, Java and Python. All APIs use exceptions for error reporting but each of them exploits advanced features of a given language to simplify the end-user program writing. For example, as C++ lacks language support for exceptions, a number of macros have been designed to generate hierarchies of C++ exception classes at compile time. Using this approach a software developer can write a single line of code to generate a boilerplate code for a fully qualified C++ exception class declaration with arbitrary number of parameters and multiple constructors, which encapsulates all relevant static information about the given type of issues. When a corresponding error occurs at run time, the program just need to create an instance of that class passing relevant values to one of the available class constructors and send this instance to ERS. This paper presents the original design solutions exploited for the ERS implementation and describes how it was used during the first ATLAS run period. The cross-system error reporting standardization introduced by ERS was one of the key points for the successful implementation of automated mechanisms for online error recovery.

Evidence Report: Risk of Performance Errors Due to Training Deficiencies

NASA Technical Reports Server (NTRS)

Barshi, Immanuel

2012-01-01

The Risk of Performance Errors Due to Training Deficiencies is identified by the National Aeronautics and Space Administration (NASA) Human Research Program (HRP) as a recognized risk to human health and performance in space. The HRP Program Requirements Document (PRD) defines these risks. This Evidence Report provides a summary of the evidence that has been used to identify and characterize this risk. Given that training content, timing, intervals, and delivery methods must support crew task performance, and given that training paradigms will be different for long-duration missions with increased crew autonomy, there is a risk that operators will lack the skills or knowledge necessary to complete critical tasks, resulting in flight and ground crew errors and inefficiencies, failed mission and program objectives, and an increase in crew injuries.

Observations of fallibility in applications of modern programming methodologies

NASA Technical Reports Server (NTRS)

Gerhart, S. L.; Yelowitz, L.

1976-01-01

Errors, inconsistencies, or confusing points are noted in a variety of published algorithms, many of which are being used as examples in formulating or teaching principles of such modern programming methodologies as formal specification, systematic construction, and correctness proving. Common properties of these points of contention are abstracted. These properties are then used to pinpoint possible causes of the errors and to formulate general guidelines which might help to avoid further errors. The common characteristic of mathematical rigor and reasoning in these examples is noted, leading to some discussion about fallibility in mathematics, and its relationship to fallibility in these programming methodologies. The overriding goal is to cast a more realistic perspective on the methodologies, particularly with respect to older methodologies, such as testing, and to provide constructive recommendations for their improvement.

The use of self checks and voting in software error detection - An empirical study

NASA Technical Reports Server (NTRS)

Leveson, Nancy G.; Cha, Stephen S.; Knight, John C.; Shimeall, Timothy J.

1990-01-01

The results of an empirical study of software error detection using self checks and N-version voting are presented. Working independently, each of 24 programmers first prepared a set of self checks using just the requirements specification of an aerospace application, and then each added self checks to an existing implementation of that specification. The modified programs were executed to measure the error-detection performance of the checks and to compare this with error detection using simple voting among multiple versions. The analysis of the checks revealed that there are great differences in the ability of individual programmers to design effective checks. It was found that some checks that might have been effective failed to detect an error because they were badly placed, and there were numerous instances of checks signaling nonexistent errors. In general, specification-based checks alone were not as effective as specification-based checks combined with code-based checks. Self checks made it possible to identify faults that had not been detected previously by voting 28 versions of the program over a million randomly generated inputs. This appeared to result from the fact that the self checks could examine the internal state of the executing program, whereas voting examines only final results of computations. If internal states had to be identical in N-version voting systems, then there would be no reason to write multiple versions.

78 FR 33810 - Fishing Capacity Reduction Program for the Southeast Alaska Purse Seine Salmon Fishery

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-05

... Capacity Reduction Program for the Southeast Alaska Purse Seine Salmon Fishery AGENCY: National Marine... reduction loan for the fishing capacity reduction program in the Southeast Alaska purse seine salmon fishery... July 22, 2012. Since then, all harvesters of Southeast Alaska purse seine salmon must pay the fee and...

Mindfulness-Based Stress Reduction in Post-treatment Breast Cancer Patients: Immediate and Sustained Effects Across Multiple Symptom Clusters.

PubMed

Reich, Richard R; Lengacher, Cecile A; Alinat, Carissa B; Kip, Kevin E; Paterson, Carly; Ramesar, Sophia; Han, Heather S; Ismail-Khan, Roohi; Johnson-Mallard, Versie; Moscoso, Manolete; Budhrani-Shani, Pinky; Shivers, Steve; Cox, Charles E; Goodman, Matthew; Park, Jong

2017-01-01

Breast cancer survivors (BCS) face adverse physical and psychological symptoms, often co-occurring. Biologic and psychological factors may link symptoms within clusters, distinguishable by prevalence and/or severity. Few studies have examined the effects of behavioral interventions or treatment of symptom clusters. The aim of this study was to identify symptom clusters among post-treatment BCS and determine symptom cluster improvement following the Mindfulness-Based Stress Reduction for Breast Cancer (MBSR(BC)) program. Three hundred twenty-two Stage 0-III post-treatment BCS were randomly assigned to either a six-week MBSR(BC) program or usual care. Psychological (depression, anxiety, stress, and fear of recurrence), physical (fatigue, pain, sleep, and drowsiness), and cognitive symptoms and quality of life were assessed at baseline, six, and 12 weeks, along with demographic and clinical history data at baseline. A three-step analytic process included the error-accounting models of factor analysis and structural equation modeling. Four symptom clusters emerged at baseline: pain, psychological, fatigue, and cognitive. From baseline to six weeks, the model demonstrated evidence of MBSR(BC) effectiveness in both the psychological (anxiety, depression, perceived stress and QOL, emotional well-being) (P = 0.007) and fatigue (fatigue, sleep, and drowsiness) (P < 0.001) clusters. Results between six and 12 weeks showed sustained effects, but further improvement was not observed. Our results provide clinical effectiveness evidence that MBSR(BC) works to improve symptom clusters, particularly for psychological and fatigue symptom clusters, with the greatest improvement occurring during the six-week program with sustained effects for several weeks after MBSR(BC) training. Name and URL of Registry: ClinicalTrials.gov. Registration number: NCT01177124. Copyright © 2016. Published by Elsevier Inc.

Calculation of cosmic ray induced single event upsets: Program CRUP (Cosmic Ray Upset Program)

NASA Astrophysics Data System (ADS)

Shapiro, P.

1983-09-01

This report documents PROGRAM CRUP, COSMIC RAY UPSET PROGRAM. The computer program calculates cosmic ray induced single-event error rates in microelectronic circuits exposed to several representative cosmic-ray environments.

Influence of an independent quarterly audit on publicly reported vancomycin-resistant enterocococi bacteremia data in Ontario, Canada.

PubMed

Prematunge, Chatura; Policarpio, Michelle E; Johnstone, Jennie; Adomako, Kwaku; Nadolny, Emily; Lam, Freda; Li, Ye; Brown, Kevin A; Garber, Gary

2018-04-13

All Ontario hospitals are mandated to self-report vancomycin-resistant enterocococi (VRE) bacteremias to Ontario's Ministry of Health and Long-term Care for public reporting purposes. Independent quarterly audits of publicly reported VRE bacteremias between September 2013 and June 2015 were carried out by Public Health Ontario. VRE bacteremia case-reporting errors between January 2009 and August 2013 were identified by a single retrospective audit. Employing a quasiexperimental pre-post study design, the relative risk of VRE bacteremia reporting errors before and after quarterly audits were modeled using Poisson regression adjusting for hospital type, case counts reported to the Ministry of Health and Long-term Care, and autocorrelation via generalized estimating equation. Overall, 24.5% (126 out of 514) of VRE bacteremias were reported in error; 114 out of 367 (31%) VRE bacteremias reported before quarterly audits and 12 out of 147 (8.1%) reported after audits were found to be incorrect. In adjusted analysis, quarterly audits of VRE bacteremias were associated with significant reductions in reporting errors when compared with before quarterly auditing (relative risk, 0.17; 95% confidence interval, 0.05-0.63). Risk of reporting errors among community hospitals were greater than acute teaching hospitals of the region (relative risk, 4.39; 95% CI, 3.07-5.70). This study found independent quarterly audits of publicly reported VRE bacteremias to be associated with significant reductions in reporting errors. Public reporting systems should consider adopting routine data audits and hospital-targeted training to improve data accuracy. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

Using lean to improve medication administration safety: in search of the "perfect dose".

PubMed

Ching, Joan M; Long, Christina; Williams, Barbara L; Blackmore, C Craig

2013-05-01

At Virginia Mason Medical Center (Seattle), the Collaborative Alliance for Nursing Outcomes (CALNOC) Medication Administration Accuracy Quality Study was used in combination with Lean quality improvement efforts to address medication administration safety. Lean interventions were targeted at improving the medication room layout, applying visual controls, and implementing nursing standard work. The interventions were designed to prevent medication administration errors through improving six safe practices: (1) comparing medication with medication administration record, (2) labeling medication, (3) checking two forms of patient identification, (4) explaining medication to patient, (5) charting medication immediately, and (6) protecting the process from distractions/interruptions. Trained nurse auditors observed 9,244 doses for 2,139 patients. Following the intervention, the number of safe-practice violations decreased from 83 violations/100 doses at baseline (January 2010-March 2010) to 42 violations/100 doses at final follow-up (July 2011-September 2011), resulting in an absolute risk reduction of 42 violations/100 doses (95% confidence interval [CI]: 35-48), p < .001). The number of medication administration errors decreased from 10.3 errors/100 doses at baseline to 2.8 errors/100 doses at final follow-up (absolute risk reduction: 7 violations/100 doses [95% CI: 5-10, p < .001]). The "perfect dose" score, reflecting compliance with all six safe practices and absence of any of the eight medication administration errors, improved from 37 in compliance/100 doses at baseline to 68 in compliance/100 doses at the final follow-up. Lean process improvements coupled with direct observation can contribute to substantial decreases in errors in nursing medication administration.

Impact of Feedback on Three Phases of Performance Monitoring

PubMed Central

Appelgren, Alva; Penny, William; Bengtsson, Sara L

2013-01-01

We investigated if certain phases of performance monitoring show differential sensitivity to external feedback and thus rely on distinct mechanisms. The phases of interest were: the error phase (FE), the phase of the correct response after errors (FEC), and the phase of correct responses following corrects (FCC). We tested accuracy and reaction time (RT) on 12 conditions of a continuous-choice-response task; the 2-back task. External feedback was either presented or not in FE and FEC, and delivered on 0%, 20%, or 100% of FCC trials. The FCC20 was matched to FE and FEC in the number of sounds received so that we could investigate when external feedback was most valuable to the participants. We found that external feedback led to a reduction in accuracy when presented on all the correct responses. Moreover, RT was significantly reduced for FCC100, which in turn correlated with the accuracy reduction. Interestingly, the correct response after an error was particularly sensitive to external feedback since accuracy was reduced when external feedback was presented during this phase but not for FCC20. Notably, error-monitoring was not influenced by feedback-type. The results are in line with models suggesting that the internal error-monitoring system is sufficient in cognitively demanding tasks where performance is ∼ 80%, as well as theories stipulating that external feedback directs attention away from the task. Our data highlight the first correct response after an error as particularly sensitive to external feedback, suggesting that important consolidation of response strategy takes place here. PMID:24217138

Syntactic and semantic errors in radiology reports associated with speech recognition software.

PubMed

Ringler, Michael D; Goss, Brian C; Bartholmai, Brian J

2017-03-01

Speech recognition software can increase the frequency of errors in radiology reports, which may affect patient care. We retrieved 213,977 speech recognition software-generated reports from 147 different radiologists and proofread them for errors. Errors were classified as "material" if they were believed to alter interpretation of the report. "Immaterial" errors were subclassified as intrusion/omission or spelling errors. The proportion of errors and error type were compared among individual radiologists, imaging subspecialty, and time periods. In all, 20,759 reports (9.7%) contained errors, of which 3992 (1.9%) were material errors. Among immaterial errors, spelling errors were more common than intrusion/omission errors ( p < .001). Proportion of errors and fraction of material errors varied significantly among radiologists and between imaging subspecialties ( p < .001). Errors were more common in cross-sectional reports, reports reinterpreting results of outside examinations, and procedural studies (all p < .001). Error rate decreased over time ( p < .001), which suggests that a quality control program with regular feedback may reduce errors.

Improving the quality of cognitive screening assessments: ACEmobile, an iPad-based version of the Addenbrooke's Cognitive Examination-III.

PubMed

Newman, Craig G J; Bevins, Adam D; Zajicek, John P; Hodges, John R; Vuillermoz, Emil; Dickenson, Jennifer M; Kelly, Denise S; Brown, Simona; Noad, Rupert F

2018-01-01

Ensuring reliable administration and reporting of cognitive screening tests are fundamental in establishing good clinical practice and research. This study captured the rate and type of errors in clinical practice, using the Addenbrooke's Cognitive Examination-III (ACE-III), and then the reduction in error rate using a computerized alternative, the ACEmobile app. In study 1, we evaluated ACE-III assessments completed in National Health Service (NHS) clinics ( n  = 87) for administrator error. In study 2, ACEmobile and ACE-III were then evaluated for their ability to capture accurate measurement. In study 1, 78% of clinically administered ACE-IIIs were either scored incorrectly or had arithmetical errors. In study 2, error rates seen in the ACE-III were reduced by 85%-93% using ACEmobile. Error rates are ubiquitous in routine clinical use of cognitive screening tests and the ACE-III. ACEmobile provides a framework for supporting reduced administration, scoring, and arithmetical error during cognitive screening.

How Trainees Would Disclose Medical Errors: Educational Implications for Training Programs

PubMed Central

White, Andrew A.; Bell, Sigall K.; Krauss, Melissa J; Garbutt, Jane; Dunagan, W. Claiborne; Fraser, Victoria J.; Levinson, Wendy; Larson, Eric B.; Gallagher, Thomas H.

2012-01-01

Background Disclosing harmful errors to patients is recommended, but appears to be uncommon. Understanding how trainees disclose errors and how those practices evolve during training could help educators design programs to address this gap. Purpose To determine how trainees would disclose medical errors. Methods A survey of 758 trainees (488 students and 270 residents) in internal medicine at two academic medical centers. Surveys depicted one of two harmful error scenarios that varied by how apparent the error would be to the patient. We measured attitudes and disclosure content using scripted responses. Results Trainees reported their intent to disclose the error as “definitely” (43%) “probably” (47%) “only if asked by patient” (9%), and “definitely not” (1%). Trainees were more likely to disclose obvious errors in comparison with ones patients were unlikely to recognize (55% vs. 30%, P<0.01). Respondents varied widely in what information they would disclose. Fifty percent of trainees chose statements explicitly stating an error occurred rather than only an adverse event. Regarding apologies, trainees were split between a general expression of regret (52%) and an explicit apology (46%). Respondents at higher levels of training were less likely to use explicit apologies (Trend P<0.01). Prior disclosure training was associated with increased willingness to disclose errors (OR 1.40, P=0.03). Conclusions Trainees may not be prepared to disclose medical errors to patients, and worrisome trends in trainee apology practices were observed across levels of training. Medical educators should intensify efforts to enhance trainees’ skills at meeting patients’ expectations for open disclosure of harmful medical errors. PMID:21401685

Specification and Error Pattern Based Program Monitoring

NASA Technical Reports Server (NTRS)

Havelund, Klaus; Johnson, Scott; Rosu, Grigore; Clancy, Daniel (Technical Monitor)

2001-01-01

We briefly present Java PathExplorer (JPAX), a tool developed at NASA Ames for monitoring the execution of Java programs. JPAX can be used not only during program testing to reveal subtle errors, but also can be applied during operation to survey safety critical systems. The tool facilitates automated instrumentation of a program in order to properly observe its execution. The instrumentation can be either at the bytecode level or at the source level when the source code is available. JPaX is an instance of a more general project, called PathExplorer (PAX), which is a basis for experiments rather than a fixed system, capable of monitoring various programming languages and experimenting with other logics and analysis techniques

Use of failure mode effect analysis (FMEA) to improve medication management process.

PubMed

Jain, Khushboo

2017-03-13

Purpose Medication management is a complex process, at high risk of error with life threatening consequences. The focus should be on devising strategies to avoid errors and make the process self-reliable by ensuring prevention of errors and/or error detection at subsequent stages. The purpose of this paper is to use failure mode effect analysis (FMEA), a systematic proactive tool, to identify the likelihood and the causes for the process to fail at various steps and prioritise them to devise risk reduction strategies to improve patient safety. Design/methodology/approach The study was designed as an observational analytical study of medication management process in the inpatient area of a multi-speciality hospital in Gurgaon, Haryana, India. A team was made to study the complex process of medication management in the hospital. FMEA tool was used. Corrective actions were developed based on the prioritised failure modes which were implemented and monitored. Findings The percentage distribution of medication errors as per the observation made by the team was found to be maximum of transcription errors (37 per cent) followed by administration errors (29 per cent) indicating the need to identify the causes and effects of their occurrence. In all, 11 failure modes were identified out of which major five were prioritised based on the risk priority number (RPN). The process was repeated after corrective actions were taken which resulted in about 40 per cent (average) and around 60 per cent reduction in the RPN of prioritised failure modes. Research limitations/implications FMEA is a time consuming process and requires a multidisciplinary team which has good understanding of the process being analysed. FMEA only helps in identifying the possibilities of a process to fail, it does not eliminate them, additional efforts are required to develop action plans and implement them. Frank discussion and agreement among the team members is required not only for successfully conducing FMEA but also for implementing the corrective actions. Practical implications FMEA is an effective proactive risk-assessment tool and is a continuous process which can be continued in phases. The corrective actions taken resulted in reduction in RPN, subjected to further evaluation and usage by others depending on the facility type. Originality/value The application of the tool helped the hospital in identifying failures in medication management process, thereby prioritising and correcting them leading to improvement.

Competition between learned reward and error outcome predictions in anterior cingulate cortex.

PubMed

Alexander, William H; Brown, Joshua W

2010-02-15

The anterior cingulate cortex (ACC) is implicated in performance monitoring and cognitive control. Non-human primate studies of ACC show prominent reward signals, but these are elusive in human studies, which instead show mainly conflict and error effects. Here we demonstrate distinct appetitive and aversive activity in human ACC. The error likelihood hypothesis suggests that ACC activity increases in proportion to the likelihood of an error, and ACC is also sensitive to the consequence magnitude of the predicted error. Previous work further showed that error likelihood effects reach a ceiling as the potential consequences of an error increase, possibly due to reductions in the average reward. We explored this issue by independently manipulating reward magnitude of task responses and error likelihood while controlling for potential error consequences in an Incentive Change Signal Task. The fMRI results ruled out a modulatory effect of expected reward on error likelihood effects in favor of a competition effect between expected reward and error likelihood. Dynamic causal modeling showed that error likelihood and expected reward signals are intrinsic to the ACC rather than received from elsewhere. These findings agree with interpretations of ACC activity as signaling both perceptions of risk and predicted reward. Copyright 2009 Elsevier Inc. All rights reserved.

A Computer-Assisted Instructional Software Program in Mathematical Problem-Solving Skills for Medication Administration for Beginning Baccalaureate Nursing Students at San Jose State University.

ERIC Educational Resources Information Center

Wahl, Sharon C.

Nursing educators and administrators are concerned about medication errors made by students which jeopardize patient safety. The inability to conceptualize and calculate medication dosages, often related to math anxiety, is implicated in such errors. A computer-assisted instruction (CAI) program is seen as a viable method of allowing students to…

FPGA Boot Loader and Scrubber

NASA Technical Reports Server (NTRS)

Wade, Randall S.; Jones, Bailey

2009-01-01

A computer program loads configuration code into a Xilinx field-programmable gate array (FPGA), reads back and verifies that code, reloads the code if an error is detected, and monitors the performance of the FPGA for errors in the presence of radiation. The program consists mainly of a set of VHDL files (wherein "VHDL" signifies "VHSIC Hardware Description Language" and "VHSIC" signifies "very-high-speed integrated circuit").

Commonly Unrecognized Error Variance in Statewide Assessment Programs: Sources of Error Variance and What Can Be Done to Reduce Them

ERIC Educational Resources Information Center

Brockmann, Frank

2011-01-01

State testing programs today are more extensive than ever, and their results are required to serve more purposes and high-stakes decisions than one might have imagined. Assessment results are used to hold schools, districts, and states accountable for student performance and to help guide a multitude of important decisions. This report describes…

A new method for the assessment of patient safety competencies during a medical school clerkship using an objective structured clinical examination

PubMed Central

Daud-Gallotti, Renata Mahfuz; Morinaga, Christian Valle; Arlindo-Rodrigues, Marcelo; Velasco, Irineu Tadeu; Arruda Martins, Milton; Tiberio, Iolanda Calvo

2011-01-01

INTRODUCTION: Patient safety is seldom assessed using objective evaluations during undergraduate medical education. OBJECTIVE: To evaluate the performance of fifth-year medical students using an objective structured clinical examination focused on patient safety after implementation of an interactive program based on adverse events recognition and disclosure. METHODS: In 2007, a patient safety program was implemented in the internal medicine clerkship of our hospital. The program focused on human error theory, epidemiology of incidents, adverse events, and disclosure. Upon completion of the program, students completed an objective structured clinical examination with five stations and standardized patients. One station focused on patient safety issues, including medical error recognition/disclosure, the patient-physician relationship and humanism issues. A standardized checklist was completed by each standardized patient to assess the performance of each student. The student's global performance at each station and performance in the domains of medical error, the patient-physician relationship and humanism were determined. The correlations between the student performances in these three domains were calculated. RESULTS: A total of 95 students participated in the objective structured clinical examination. The mean global score at the patient safety station was 87.59±1.24 points. Students' performance in the medical error domain was significantly lower than their performance on patient-physician relationship and humanistic issues. Less than 60% of students (n = 54) offered the simulated patient an apology after a medical error occurred. A significant correlation was found between scores obtained in the medical error domains and scores related to both the patient-physician relationship and humanistic domains. CONCLUSIONS: An objective structured clinical examination is a useful tool to evaluate patient safety competencies during the medical student clerkship. PMID:21876976

[The effectiveness of error reporting promoting strategy on nurse's attitude, patient safety culture, intention to report and reporting rate].

PubMed

Kim, Myoungsoo

2010-04-01

The purpose of this study was to examine the impact of strategies to promote reporting of errors on nurses' attitude to reporting errors, organizational culture related to patient safety, intention to report and reporting rate in hospital nurses. A nonequivalent control group non-synchronized design was used for this study. The program was developed and then administered to the experimental group for 12 weeks. Data were analyzed using descriptive analysis, X(2)-test, t-test, and ANCOVA with the SPSS 12.0 program. After the intervention, the experimental group showed significantly higher scores for nurses' attitude to reporting errors (experimental: 20.73 vs control: 20.52, F=5.483, p=.021) and reporting rate (experimental: 3.40 vs control: 1.33, F=1998.083, p<.001). There was no significant difference in some categories for organizational culture and intention to report. The study findings indicate that strategies that promote reporting of errors play an important role in producing positive attitudes to reporting errors and improving behavior of reporting. Further advanced strategies for reporting errors that can lead to improved patient safety should be developed and applied in a broad range of hospitals.

The prediction of satellite ephemeris errors as they result from surveillance system measurement errors

NASA Astrophysics Data System (ADS)

Simmons, B. E.

1981-08-01

This report derives equations predicting satellite ephemeris error as a function of measurement errors of space-surveillance sensors. These equations lend themselves to rapid computation with modest computer resources. They are applicable over prediction times such that measurement errors, rather than uncertainties of atmospheric drag and of Earth shape, dominate in producing ephemeris error. This report describes the specialization of these equations underlying the ANSER computer program, SEEM (Satellite Ephemeris Error Model). The intent is that this report be of utility to users of SEEM for interpretive purposes, and to computer programmers who may need a mathematical point of departure for limited generalization of SEEM.

Improvement of tsunami detection in timeseries data of GPS buoys with the Continuous Wavelet Transform

NASA Astrophysics Data System (ADS)

Chida, Y.; Takagawa, T.

2017-12-01

The observation data of GPS buoys which are installed in the offshore of Japan are used for monitoring not only waves but also tsunamis in Japan. The real-time data was successfully used to upgrade the tsunami warnings just after the 2011 Tohoku earthquake. Huge tsunamis can be easily detected because the signal-noise ratio is high enough, but moderate tsunami is not. GPS data sometimes include the error waveforms like tsunamis because of changing accuracy by the number and the position of GPS satellites. To distinguish the true tsunami waveforms from pseudo-tsunami ones is important for tsunami detection. In this research, a method to reduce misdetections of tsunami in the observation data of GPS buoys and to increase the efficiency of tsunami detection was developed.Firstly, the error waveforms were extracted by using the indexes of position dilution of precision, reliability of GPS satellite positioning and satellite number for calculation. Then, the output from this procedure was used for the Continuous Wavelet Transform (CWT) to analyze the time-frequency characteristics of error waveforms and real tsunami waveforms.We found that the error waveforms tended to appear when the accuracy of GPS buoys positioning was low. By extracting these waveforms, it was possible to decrease about 43% error waveforms without the reduction of the tsunami detection rate. Moreover, we found that the amplitudes of power spectra obtained from the error waveforms and real tsunamis were similar in the component of long period (4-65 minutes), on the other hand, the amplitude in the component of short period (< 1 minute) obtained from the error waveforms was significantly larger than that of the real tsunami waveforms. By thresholding of the short-period component, further extraction of error waveforms became possible without a significant reduction of tsunami detection rate.

78 FR 10135 - Fishing Capacity Reduction Program for the Longline Catcher Processor Subsector of the Bering Sea...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-13

... reduction loan to finance the non-pollock groundfish fishing capacity reduction program. DATES: The non... finance reduction program costs. Subpart L of 50 CFR part 600 is the framework rule generally implementing... higher fee rate will be credited to future landings. Fee collection and submission shall follow...

40 CFR 93.165 - Early emission reduction credit programs at Federal facilities and installation subject to...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Early emission reduction credit... Federal Actions to State or Federal Implementation Plans § 93.165 Early emission reduction credit programs... the SIP or TIP in that area, create an early emissions reductions credit program. The Federal agency...

40 CFR 93.165 - Early emission reduction credit programs at Federal facilities and installation subject to...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Early emission reduction credit... Federal Actions to State or Federal Implementation Plans § 93.165 Early emission reduction credit programs... the SIP or TIP in that area, create an early emissions reductions credit program. The Federal agency...

Recruitment into diabetes prevention programs: what is the impact of errors in self-reported measures of obesity?

PubMed

Hernan, Andrea; Philpot, Benjamin; Janus, Edward D; Dunbar, James A

2012-07-08

Error in self-reported measures of obesity has been frequently described, but the effect of self-reported error on recruitment into diabetes prevention programs is not well established. The aim of this study was to examine the effect of using self-reported obesity data from the Finnish diabetes risk score (FINDRISC) on recruitment into the Greater Green Triangle Diabetes Prevention Project (GGT DPP). The GGT DPP was a structured group-based lifestyle modification program delivered in primary health care settings in South-Eastern Australia. Between 2004-05, 850 FINDRISC forms were collected during recruitment for the GGT DPP. Eligible individuals, at moderate to high risk of developing diabetes, were invited to undertake baseline tests, including anthropometric measurements performed by specially trained nurses. In addition to errors in calculating total risk scores, accuracy of self-reported data (height, weight, waist circumference (WC) and Body Mass Index (BMI)) from FINDRISCs was compared with baseline data, with impact on participation eligibility presented. Overall, calculation errors impacted on eligibility in 18 cases (2.1%). Of n = 279 GGT DPP participants with measured data, errors (total score calculation, BMI or WC) in self-report were found in n = 90 (32.3%). These errors were equally likely to result in under- or over-reported risk. Under-reporting was more common in those reporting lower risk scores (Spearman-rho = -0.226, p-value < 0.001). However, underestimation resulted in only 6% of individuals at high risk of diabetes being incorrectly categorised as moderate or low risk of diabetes. Overall FINDRISC was found to be an effective tool to screen and recruit participants at moderate to high risk of diabetes, accurately categorising levels of overweight and obesity using self-report data. The results could be generalisable to other diabetes prevention programs using screening tools which include self-reported levels of obesity.

Cost effectiveness of the stream-gaging program in South Carolina

USGS Publications Warehouse

Barker, A.C.; Wright, B.C.; Bennett, C.S.

1985-01-01

The cost effectiveness of the stream-gaging program in South Carolina was documented for the 1983 water yr. Data uses and funding sources were identified for the 76 continuous stream gages currently being operated in South Carolina. The budget of $422,200 for collecting and analyzing streamflow data also includes the cost of operating stage-only and crest-stage stations. The streamflow records for one stream gage can be determined by alternate, less costly methods, and should be discontinued. The remaining 75 stations should be maintained in the program for the foreseeable future. The current policy for the operation of the 75 stations including the crest-stage and stage-only stations would require a budget of $417,200/yr. The average standard error of estimation of streamflow records is 16.9% for the present budget with missing record included. However, the standard error of estimation would decrease to 8.5% if complete streamflow records could be obtained. It was shown that the average standard error of estimation of 16.9% could be obtained at the 75 sites with a budget of approximately $395,000 if the gaging resources were redistributed among the gages. A minimum budget of $383,500 is required to operate the program; a budget less than this does not permit proper service and maintenance of the gages and recorders. At the minimum budget, the average standard error is 18.6%. The maximum budget analyzed was $850,000, which resulted in an average standard error of 7.6 %. (Author 's abstract)

Estimating Thruster Impulses From IMU and Doppler Data

NASA Technical Reports Server (NTRS)

Lisano, Michael E.; Kruizinga, Gerhard L.

2009-01-01

A computer program implements a thrust impulse measurement (TIM) filter, which processes data on changes in velocity and attitude of a spacecraft to estimate the small impulsive forces and torques exerted by the thrusters of the spacecraft reaction control system (RCS). The velocity-change data are obtained from line-of-sight-velocity data from Doppler measurements made from the Earth. The attitude-change data are the telemetered from an inertial measurement unit (IMU) aboard the spacecraft. The TIM filter estimates the threeaxis thrust vector for each RCS thruster, thereby enabling reduction of cumulative navigation error attributable to inaccurate prediction of thrust vectors. The filter has been augmented with a simple mathematical model to compensate for large temperature fluctuations in the spacecraft thruster catalyst bed in order to estimate thrust more accurately at deadbanding cold-firing levels. Also, rigorous consider-covariance estimation is applied in the TIM to account for the expected uncertainty in the moment of inertia and the location of the center of gravity of the spacecraft. The TIM filter was built with, and depends upon, a sigma-point consider-filter algorithm implemented in a Python-language computer program.

Integrated computer-aided design using minicomputers

NASA Technical Reports Server (NTRS)

Storaasli, O. O.

1980-01-01

Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM), a highly interactive software, has been implemented on minicomputers at the NASA Langley Research Center. CAD/CAM software integrates many formerly fragmented programs and procedures into one cohesive system; it also includes finite element modeling and analysis, and has been interfaced via a computer network to a relational data base management system and offline plotting devices on mainframe computers. The CAD/CAM software system requires interactive graphics terminals operating at a minimum of 4800 bits/sec transfer rate to a computer. The system is portable and introduces 'interactive graphics', which permits the creation and modification of models interactively. The CAD/CAM system has already produced designs for a large area space platform, a national transonic facility fan blade, and a laminar flow control wind tunnel model. Besides the design/drafting element analysis capability, CAD/CAM provides options to produce an automatic program tooling code to drive a numerically controlled (N/C) machine. Reductions in time for design, engineering, drawing, finite element modeling, and N/C machining will benefit productivity through reduced costs, fewer errors, and a wider range of configuration.

Examining Teaching Based on Errors in Mathematics Amongst Pupils with Learning Disabilities

ERIC Educational Resources Information Center

Magen-Nagar, Noga

2016-01-01

Teaching mathematics while learning from students' mistakes, errors and misconceptions, is most important for meaningful learning. This study was based on intervention programs prepared by preservice teachers. It aimed to examine their knowledge of assessment of errors in mathematics amongst pupils with learning disabilities, and their use as a…

48 CFR 22.1015 - Discovery of errors by the Department of Labor.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Discovery of errors by the... REGULATION SOCIOECONOMIC PROGRAMS APPLICATION OF LABOR LAWS TO GOVERNMENT ACQUISITIONS Service Contract Act of 1965, as Amended 22.1015 Discovery of errors by the Department of Labor. If the Department of...

Effects of Programmed Teaching Errors on Acquisition and Durability of Self-Care Skills

ERIC Educational Resources Information Center

Donnelly, Maeve G.; Karsten, Amanda M.

2017-01-01

This investigation sheds light on necessary and sufficient conditions to establish self-care behavior chains among people with developmental disabilities. First, a descriptive assessment (DA) identified the types of teaching errors that occurred during self-care instruction. Second, the relative effects of three teaching errors observed during the…

Error Analysis Of Students Working About Word Problem Of Linear Program With NEA Procedure

NASA Astrophysics Data System (ADS)

Santoso, D. A.; Farid, A.; Ulum, B.

2017-06-01

Evaluation and assessment is an important part of learning. In evaluation process of learning, written test is still commonly used. However, the tests usually do not following-up by further evaluation. The process only up to grading stage not to evaluate the process and errors which done by students. Whereas if the student has a pattern error and process error, actions taken can be more focused on the fault and why is that happen. NEA procedure provides a way for educators to evaluate student progress more comprehensively. In this study, students’ mistakes in working on some word problem about linear programming have been analyzed. As a result, mistakes are often made students exist in the modeling phase (transformation) and process skills (process skill) with the overall percentage distribution respectively 20% and 15%. According to the observations, these errors occur most commonly due to lack of precision of students in modeling and in hastiness calculation. Error analysis with students on this matter, it is expected educators can determine or use the right way to solve it in the next lesson.

Patient-Controlled Analgesia Basal Infusion Overdose; Life-threatening Errors with Flecainide Suspension in Children; Medical Product Error-Prevention Efforts Need to Be Shared and Harmonized Internationally

PubMed Central

Cohen, Michael R.; Smetzer, Judy L.

2015-01-01

These medication errors have occurred in health care facilities at least once. They will happen again—perhaps where you work. Through education and alertness of personnel and procedural safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them at your inservice training programs. Your assistance is required to continue this feature. The reports described here were received through the Institute for Safe Medication Practices (ISMP) Medication Errors Reporting Program. Any reports published by ISMP will be anonymous. Comments are also invited; the writers’ names will be published if desired. ISMP may be contacted at the address shown below. Errors, close calls, or hazardous conditions may be reported directly to ISMP through the ISMP Web site (www.ismp.org), by calling 800-FAIL-SAFE, or via e-mail at ismpinfo@ismp.org. ISMP guarantees the confidentiality and security of the information received and respects reporters’ wishes as to the level of detail included in publications. PMID:26715797

Guidelines for conducting vulnerability assessments. [Susceptibility of programs to unauthorized use of resources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1982-06-01

The US General Accounting Office and executive agency Inspectors General have reported losses of millions of dollars in government funds resulting from fraud, waste and error. The Administration and the Congress have initiated determined efforts to eliminate such losses from government programs and activities. Primary emphasis in this effort is on the strengthening of accounting and administrative controls. Accordingly, the Office of Management and Budget (OMB) issued Circular No. A-123, Internal Control Systems, on October 28, 1981. The campaign to improve internal controls was endorsed by the Secretary of Energy in a memorandum to Heads of Departmental Components, dated Marchmore » 13, 1981, Subject: Internal Control as a Deterrent to Fraud, Waste and Error. A vulnerability assessment is a review of the susceptibility of a program or function to unauthorized use of resources, errors in reports and information, and illegal or unethical acts. It is based on considerations of the environment in which the program or function is carried out, the inherent riskiness of the program or function, and a preliminary evaluation as to whether adequate safeguards exist and are functioning.« less

Theoretical and experimental errors for in situ measurements of plant water potential.

PubMed

Shackel, K A

1984-07-01

Errors in psychrometrically determined values of leaf water potential caused by tissue resistance to water vapor exchange and by lack of thermal equilibrium were evaluated using commercial in situ psychrometers (Wescor Inc., Logan, UT) on leaves of Tradescantia virginiana (L.). Theoretical errors in the dewpoint method of operation for these sensors were demonstrated. After correction for these errors, in situ measurements of leaf water potential indicated substantial errors caused by tissue resistance to water vapor exchange (4 to 6% reduction in apparent water potential per second of cooling time used) resulting from humidity depletions in the psychrometer chamber during the Peltier condensation process. These errors were avoided by use of a modified procedure for dewpoint measurement. Large changes in apparent water potential were caused by leaf and psychrometer exposure to moderate levels of irradiance. These changes were correlated with relatively small shifts in psychrometer zero offsets (-0.6 to -1.0 megapascals per microvolt), indicating substantial errors caused by nonisothermal conditions between the leaf and the psychrometer. Explicit correction for these errors is not possible with the current psychrometer design.

Theoretical and Experimental Errors for In Situ Measurements of Plant Water Potential 1

PubMed Central

Shackel, Kenneth A.

1984-01-01

Errors in psychrometrically determined values of leaf water potential caused by tissue resistance to water vapor exchange and by lack of thermal equilibrium were evaluated using commercial in situ psychrometers (Wescor Inc., Logan, UT) on leaves of Tradescantia virginiana (L.). Theoretical errors in the dewpoint method of operation for these sensors were demonstrated. After correction for these errors, in situ measurements of leaf water potential indicated substantial errors caused by tissue resistance to water vapor exchange (4 to 6% reduction in apparent water potential per second of cooling time used) resulting from humidity depletions in the psychrometer chamber during the Peltier condensation process. These errors were avoided by use of a modified procedure for dewpoint measurement. Large changes in apparent water potential were caused by leaf and psychrometer exposure to moderate levels of irradiance. These changes were correlated with relatively small shifts in psychrometer zero offsets (−0.6 to −1.0 megapascals per microvolt), indicating substantial errors caused by nonisothermal conditions between the leaf and the psychrometer. Explicit correction for these errors is not possible with the current psychrometer design. PMID:16663701

LACIE performance predictor final operational capability program description, volume 3

NASA Technical Reports Server (NTRS)

1976-01-01

The requirements and processing logic for the LACIE Error Model program (LEM) are described. This program is an integral part of the Large Area Crop Inventory Experiment (LACIE) system. LEM is that portion of the LPP (LACIE Performance Predictor) which simulates the sample segment classification, strata yield estimation, and production aggregation. LEM controls repetitive Monte Carlo trials based on input error distributions to obtain statistical estimates of the wheat area, yield, and production at different levels of aggregation. LEM interfaces with the rest of the LPP through a set of data files.

Implementation of an experimental program to investigate the performance characteristics of OMEGA navigation

NASA Technical Reports Server (NTRS)

Baxa, E. G., Jr.

1974-01-01

A theoretical formulation of differential and composite OMEGA error is presented to establish hypotheses about the functional relationships between various parameters and OMEGA navigational errors. Computer software developed to provide for extensive statistical analysis of the phase data is described. Results from the regression analysis used to conduct parameter sensitivity studies on differential OMEGA error tend to validate the theoretically based hypothesis concerning the relationship between uncorrected differential OMEGA error and receiver separation range and azimuth. Limited results of measurement of receiver repeatability error and line of position measurement error are also presented.

Simulation gravity modeling to spacecraft-tracking data - Analysis and application

NASA Technical Reports Server (NTRS)

Phillips, R. J.; Sjogren, W. L.; Abbott, E. A.; Zisk, S. H.

1978-01-01

It is proposed that line-of-sight gravity measurements derived from spacecraft-tracking data can be used for quantitative subsurface density modeling by suitable orbit simulation procedures. Such an approach avoids complex dynamic reductions and is analogous to the modeling of conventional surface gravity data. This procedure utilizes the vector calculations of a given gravity model in a simplified trajectory integration program that simulates the line-of-sight gravity. Solutions from an orbit simulation inversion and a dynamic inversion on Doppler observables compare well (within 1% in mass and size), and the error sources in the simulation approximation are shown to be quite small. An application of this technique is made to lunar crater gravity anomalies by simulating the complete Bouguer correction to several large young lunar craters. It is shown that the craters all have negative Bouguer anomalies.

Embracing Errors in Simulation-Based Training: The Effect of Error Training on Retention and Transfer of Central Venous Catheter Skills.

PubMed

Gardner, Aimee K; Abdelfattah, Kareem; Wiersch, John; Ahmed, Rami A; Willis, Ross E

2015-01-01

Error management training is an approach that encourages exposure to errors during initial skill acquisition so that learners can be equipped with important error identification, management, and metacognitive skills. The purpose of this study was to determine how an error-focused training program affected performance, retention, and transfer of central venous catheter (CVC) placement skills when compared with traditional training methodologies. Surgical interns (N = 30) participated in a 1-hour session featuring an instructional video and practice performing internal jugular (IJ) and subclavian (SC) CVC placement with guided instruction. All interns underwent baseline knowledge and skill assessment for IJ and SC (pretest) CVC placement; watched a "correct-only" (CO) or "correct + error" (CE) instructional video; practiced for 30 minutes; and were posttested on knowledge and IJ and SC CVC placement. Skill retention and transfer (femoral CVC placement) were assessed 30 days later. All skills tests (pretest, posttest, and transfer) were videorecorded and deidentified for evaluation by a single blinded instructor using a validated 17-item checklist. Both the groups exhibited significant improvements (p < 0.001) in knowledge and skills after the 1-hour training program, but the increase of items achieved on the performance checklist did not differ between conditions (CO: IJ Δ = 35%, SC Δ = 29%; CE: IJ Δ = 36%, subclavian Δ = 33%). However, 1 month later, the CO group exhibited significant declines in skill retention on IJ CVC placement (from 68% at posttraining to 44% at day 30; p < 0.05) and SC CVC placement (from 63% at posttraining to 49% at day 30; p < 0.05), whereas the CE group did not have significant decreases in performance. The CE group performed significantly better on femoral CVC placement (i.e., transfer task; 62% vs 38%; p < 0.01) and on 2 of the 3 complication scenarios (p < 0.05) when compared with the CO group. These data indicate that incorporating error-based activities and discussions into training programs can be beneficial for skill retention and transfer. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Procedures for dealing with certain types of noise and systematic errors common to many Hadamard transform optical systems

NASA Technical Reports Server (NTRS)

Harwit, M.

1977-01-01

Sources of noise and error correcting procedures characteristic of Hadamard transform optical systems were investigated. Reduction of spectral noise due to noise spikes in the data, the effect of random errors, the relative performance of Fourier and Hadamard transform spectrometers operated under identical detector-noise-limited conditions, and systematic means for dealing with mask defects are among the topics discussed. The distortion in Hadamard transform optical instruments caused by moving Masks, incorrect mask alignment, missing measurements, and diffraction is analyzed and techniques for reducing or eliminating this distortion are described.

Conditional cash transfers are associated with a small reduction in the rate of weight gain of preschool children in northeast Brazil.

PubMed

Morris, Saul S; Olinto, Pedro; Flores, Rafael; Nilson, Eduardo A F; Figueiró, Ana C

2004-09-01

Programs providing cash transfers to poor families, conditioned upon uptake of preventive health services, are common in Latin America. Because of the consistent association between undernutrition and poverty, and the role of health services in providing growth promotion, these programs are supposed to improve children's growth. The impact of such a program was assessed in 4 municipalities in northeast Brazil by comparing 1387 children under 7 y of age from program beneficiary households with 502 matched nonbeneficiaries who were selected to receive the program but who subsequently were excluded as a result of quasi-random administrative errors. Anthropometric status was assessed 6 mo after benefits began to be distributed, and beneficiary children were 0.13 Z-scores lighter (weight-for-age) than excluded children, after adjusting for confounders (P = 0.024). The children's growth trajectories were reconstructed by copying up to 10 recorded weights from their Ministry of Health growth monitoring cards and by relating each weight to the child's age, gender, and duration of receipt of the program benefit in a random effects regression model. Totals of 472 beneficiary and 158 excluded children under 3 y of age were included in this analysis. Each additional month of exposure to the program was associated with a rate of weight gain 31 g lower than that observed in excluded children of the same age (P < 0.001). This failure to respond positively to the program may have been due to a perception that benefits would be discontinued if the child started to grow well. Nutrition programs should guard against giving the impression that poor growth will be rewarded.

Effectiveness of a Hospital-Based Multidisciplinary Pediatric Weight Management Program: Two-Year Outcomes of PHIT Kids.

PubMed

Hampl, Sarah; Odar Stough, Cathleen; Poppert Cordts, Katrina; Best, Cora; Blackburn, Katherine; Dreyer Gillette, Meredith L

2016-02-01

For children with obesity, long-term sustainability of weight loss after treatment is difficult to achieve. This study examined 2-year anthropometric outcomes of a moderately intensive group behaviorally based weight management program. One hundred seventy-three children with obesity ages 8-18 years participated with their parent or adult caregiver in a 24-week multicomponent intervention, which was followed by monthly sessions for a total of 2 years. Children were considered treatment completers if they attended ≥50% of the 24 weekly sessions. A multilevel model (multiple assessment time points nested within participants) was used to test person-level change in BMI z-score (BMIz) for program completers between (1) pre- and post-treatment, (2) pretreatment and 24-month follow-up, (3) post-treatment and 12-month follow-up, and (4) post-treatment and 24-month follow-up. One hundred twenty-four (72%) of the participants completed the 24-week intervention. Significant reductions in BMIz were observed over the course of treatment (β = -0.03; standard error [SE] = 0.004; t = -6.85; p < 0.001). Completers showed a significant reduction in BMIz between initiation of treatment and 2-year follow-up (n = 110 at 24 weeks; n = 38 at 24 months; β = -0.02; SE = 0.005; t = -4.12; p < 0.001). Children did not show any significant changes in BMIz between post-treatment and 24-month follow-up (β = -0.006; SE = 0.011; t = -0.61; p = 0.54), suggesting that treatment effects were maintained. Children maintained treatment gains achieved during a 24-week family-based behavioral weight management program at 2-year follow-up. Although these findings suggest that gains are sustainable, further research is needed to understand how these long-term changes impact child health.

Inadvertently programmed bits in Samsung 128 Mbit flash devices: a flaky investigation

NASA Technical Reports Server (NTRS)

Swift, G.

2002-01-01

JPL's X2000 avionics design pioneers new territory by specifying a non-volatile memory (NVM) board based on flash memories. The Samsung 128Mb device chosen was found to demonstrate bit errors (mostly program disturbs) and block-erase failures that increase with cycling. Low temperature, certain pseudo- random patterns, and, probably, higher bias increase the observable bit errors. An experiment was conducted to determine the wearout dependence of the bit errors to 100k cycles at cold temperature using flight-lot devices (some pre-irradiated). The results show an exponential growth rate, a wide part-to-part variation, and some annealing behavior.

Effects of skilled nursing facility structure and process factors on medication errors during nursing home admission.

PubMed

Lane, Sandi J; Troyer, Jennifer L; Dienemann, Jacqueline A; Laditka, Sarah B; Blanchette, Christopher M

2014-01-01

Older adults are at greatest risk of medication errors during the transition period of the first 7 days after admission and readmission to a skilled nursing facility (SNF). The aim of this study was to evaluate structure- and process-related factors that contribute to medication errors and harm during transition periods at a SNF. Data for medication errors and potential medication errors during the 7-day transition period for residents entering North Carolina SNFs were from the Medication Error Quality Initiative-Individual Error database from October 2006 to September 2007. The impact of SNF structure and process measures on the number of reported medication errors and harm from errors were examined using bivariate and multivariate model methods. A total of 138 SNFs reported 581 transition period medication errors; 73 (12.6%) caused harm. Chain affiliation was associated with a reduction in the volume of errors during the transition period. One third of all reported transition errors occurred during the medication administration phase of the medication use process, where dose omissions were the most common type of error; however, dose omissions caused harm less often than wrong-dose errors did. Prescribing errors were much less common than administration errors but were much more likely to cause harm. Both structure and process measures of quality were related to the volume of medication errors.However, process quality measures may play a more important role in predicting harm from errors during the transition of a resident into an SNF. Medication errors during transition could be reduced by improving both prescribing processes and transcription and documentation of orders.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, J; Hu, W; Xing, Y

Purpose: Different particle scanning beam delivery systems have different delivery accuracies. This study was performed to determine, for our particle treatment system, an appropriate composition (n=FWHM/GS) of spot size(FWHM) and grid size (GS), which can provide homogenous delivered dose distributions for both proton and heavy ion scanning beam radiotherapy. Methods: We analyzed the delivery errors of our beam delivery system using log files from the treatment of 28 patients. We used a homemade program to simulate square fields for different n values with and without considering the delivery errors and analyzed the homogeneity. All spots were located on a rectilinearmore » grid with equal spacing in the × and y directions. After that, we selected 7 energy levels for both proton and carbon ions. For each energy level, we made 6 square field plans with different n values (1, 1.5, 2, 2.5, 3, 3.5). Then we delivered those plans and used films to measure the homogeneity of each field. Results: For program simulation without delivery errors, when n≥1.1 the homogeneity can be within ±3%. For both proton and carbon program simulations with delivery errors and film measurements, the homogeneity can be within ±3% when n≥2.5. Conclusion: For our facility with system errors, the n≥2.5 is appropriate for maintaining homogeneity within ±3%.« less

Meteorological Error Budget Using Open Source Data

DTIC Science & Technology

2016-09-01

ARL-TR-7831 ● SEP 2016 US Army Research Laboratory Meteorological Error Budget Using Open- Source Data by J Cogan, J Smith, P...needed. Do not return it to the originator. ARL-TR-7831 ● SEP 2016 US Army Research Laboratory Meteorological Error Budget Using...Error Budget Using Open-Source Data 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) J Cogan, J Smith, P Haines

Porous plug for reducing orifice induced pressure error in airfoils

NASA Technical Reports Server (NTRS)

Plentovich, Elizabeth B. (Inventor); Gloss, Blair B. (Inventor); Eves, John W. (Inventor); Stack, John P. (Inventor)

1988-01-01

A porous plug is provided for the reduction or elimination of positive error caused by the orifice during static pressure measurements of airfoils. The porous plug is press fitted into the orifice, thereby preventing the error caused either by fluid flow turning into the exposed orifice or by the fluid flow stagnating at the downstream edge of the orifice. In addition, the porous plug is made flush with the outer surface of the airfoil, by filing and polishing, to provide a smooth surface which alleviates the error caused by imperfections in the orifice. The porous plug is preferably made of sintered metal, which allows air to pass through the pores, so that the static pressure measurements can be made by remote transducers.

How Much Confidence Can We Have in EU-SILC? Complex Sample Designs and the Standard Error of the Europe 2020 Poverty Indicators

ERIC Educational Resources Information Center

Goedeme, Tim

2013-01-01

If estimates are based on samples, they should be accompanied by appropriate standard errors and confidence intervals. This is true for scientific research in general, and is even more important if estimates are used to inform and evaluate policy measures such as those aimed at attaining the Europe 2020 poverty reduction target. In this article I…

Position Tracking During Human Walking Using an Integrated Wearable Sensing System.

PubMed

Zizzo, Giulio; Ren, Lei

2017-12-10

Progress has been made enabling expensive, high-end inertial measurement units (IMUs) to be used as tracking sensors. However, the cost of these IMUs is prohibitive to their widespread use, and hence the potential of low-cost IMUs is investigated in this study. A wearable low-cost sensing system consisting of IMUs and ultrasound sensors was developed. Core to this system is an extended Kalman filter (EKF), which provides both zero-velocity updates (ZUPTs) and Heuristic Drift Reduction (HDR). The IMU data was combined with ultrasound range measurements to improve accuracy. When a map of the environment was available, a particle filter was used to impose constraints on the possible user motions. The system was therefore composed of three subsystems: IMUs, ultrasound sensors, and a particle filter. A Vicon motion capture system was used to provide ground truth information, enabling validation of the sensing system. Using only the IMU, the system showed loop misclosure errors of 1% with a maximum error of 4-5% during walking. The addition of the ultrasound sensors resulted in a 15% reduction in the total accumulated error. Lastly, the particle filter was capable of providing noticeable corrections, which could keep the tracking error below 2% after the first few steps.

High-density force myography: A possible alternative for upper-limb prosthetic control.

PubMed

Radmand, Ashkan; Scheme, Erik; Englehart, Kevin

2016-01-01

Several multiple degree-of-freedom upper-limb prostheses that have the promise of highly dexterous control have recently been developed. Inadequate controllability, however, has limited adoption of these devices. Introducing more robust control methods will likely result in higher acceptance rates. This work investigates the suitability of using high-density force myography (HD-FMG) for prosthetic control. HD-FMG uses a high-density array of pressure sensors to detect changes in the pressure patterns between the residual limb and socket caused by the contraction of the forearm muscles. In this work, HD-FMG outperforms the standard electromyography (EMG)-based system in detecting different wrist and hand gestures. With the arm in a fixed, static position, eight hand and wrist motions were classified with 0.33% error using the HD-FMG technique. Comparatively, classification errors in the range of 2.2%-11.3% have been reported in the literature for multichannel EMG-based approaches. As with EMG, position variation in HD-FMG can introduce classification error, but incorporating position variation into the training protocol reduces this effect. Channel reduction was also applied to the HD-FMG technique to decrease the dimensionality of the problem as well as the size of the sensorized area. We found that with informed, symmetric channel reduction, classification error could be decreased to 0.02%.

Cost effectiveness of the U.S. Geological Survey's stream-gaging program in Wisconsin

USGS Publications Warehouse

Walker, J.F.; Osen, L.L.; Hughes, P.E.

1987-01-01

A minimum budget of $510,000 is required to operate the program; a budget less than this does not permit proper service and maintenance of the gaging stations. At this minimum budget, the theoretical average standard error of instantaneous discharge is 14.4%. The maximum budget analyzed was $650,000 and resulted in an average standard of error of instantaneous discharge of 7.2%. 

Least-Squares Curve-Fitting Program

NASA Technical Reports Server (NTRS)

Kantak, Anil V.

1990-01-01

Least Squares Curve Fitting program, AKLSQF, easily and efficiently computes polynomial providing least-squares best fit to uniformly spaced data. Enables user to specify tolerable least-squares error in fit or degree of polynomial. AKLSQF returns polynomial and actual least-squares-fit error incurred in operation. Data supplied to routine either by direct keyboard entry or via file. Written for an IBM PC X/AT or compatible using Microsoft's Quick Basic compiler.

The relationship between hand hygiene and health care-associated infection: it’s complicated

PubMed Central

McLaws, Mary-Louise

2015-01-01

The reasoning that improved hand hygiene compliance contributes to the prevention of health care-associated infections is widely accepted. It is also accepted that high hand hygiene alone cannot impact formidable risk factors, such as older age, immunosuppression, admission to the intensive care unit, longer length of stay, and indwelling devices. When hand hygiene interventions are concurrently undertaken with other routine or special preventive strategies, there is a potential for these concurrent strategies to confound the effect of the hand hygiene program. The result may be an overestimation of the hand hygiene intervention unless the design of the intervention or analysis controls the effect of the potential confounders. Other epidemiologic principles that may also impact the result of a hand hygiene program include failure to consider measurement error of the content of the hand hygiene program and the measurement error of compliance. Some epidemiological errors in hand hygiene programs aimed at reducing health care-associated infections are inherent and not easily controlled. Nevertheless, the inadvertent omission by authors to report these common epidemiological errors, including concurrent infection prevention strategies, suggests to readers that the effect of hand hygiene is greater than the sum of all infection prevention strategies. Worse still, this omission does not assist evidence-based practice. PMID:25678805

LOGISTIC FUNCTION PROFILE FIT: A least-squares program for fitting interface profiles to an extended logistic function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kirchhoff, William H.

2012-09-15

The extended logistic function provides a physically reasonable description of interfaces such as depth profiles or line scans of surface topological or compositional features. It describes these interfaces with the minimum number of parameters, namely, position, width, and asymmetry. Logistic Function Profile Fit (LFPF) is a robust, least-squares fitting program in which the nonlinear extended logistic function is linearized by a Taylor series expansion (equivalent to a Newton-Raphson approach) with no apparent introduction of bias in the analysis. The program provides reliable confidence limits for the parameters when systematic errors are minimal and provides a display of the residuals frommore » the fit for the detection of systematic errors. The program will aid researchers in applying ASTM E1636-10, 'Standard practice for analytically describing sputter-depth-profile and linescan-profile data by an extended logistic function,' and may also prove useful in applying ISO 18516: 2006, 'Surface chemical analysis-Auger electron spectroscopy and x-ray photoelectron spectroscopy-determination of lateral resolution.' Examples are given of LFPF fits to a secondary ion mass spectrometry depth profile, an Auger surface line scan, and synthetic data generated to exhibit known systematic errors for examining the significance of such errors to the extrapolation of partial profiles.« less

New connectors coming for enteral feeding tubes; marqibo and risk of errors; angeliq is not a birth control pill.

PubMed

Cohen, Michael R; Smetzer, Judy L

2014-07-01

These medication errors have occurred in health care facilities at least once. They will happen again-perhaps where you work. Through education and alertness of personnel and procedural safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them at your inservice training programs. Your assistance is required to continue this feature. The reports described here were received through the Institute for Safe Medication Practices (ISMP) Medication Errors Reporting Program. Any reports published by ISMP will be anonymous. Comments are also invited; the writers' names will be published if desired. ISMP may be contacted at the address shown below. Errors, close calls, or hazardous conditions may be reported directly to ISMP through the ISMP Web site (www.ismp.org), by calling 800-FAIL-SAFE, or via e-mail at ismpinfo@ismp.org. ISMP guarantees the confidentiality and security of the information received and respects reporters' wishes as to the level of detail included in publications.

[Pharmaceutical care strategies to prevent medication errors].

PubMed

Ucha-Samartín, Marisol; Martínez-López de Castro, Noemí; Troncoso-Mariño, Amelia; Campelo-Sánchez, Eva; Vázquez-López, Cristina; Inaraja-Bobo, María Teresa

2009-08-01

To evaluate the impact of implementing new programs to improve the quality of the pharmaceutical care and unit-dose distribution system for in-patients. An observational and prospective study was carried out in a general hospital during two different six-monthly period. Transcription and dispensation errors were evaluated in twelve wards during the first six months. Then, two new measures were introduced: the first- reference ward-pharmacist and the second-a new protocol for checking medication on the ward. Results were evaluated by SPSS v. 14 program. In the transcription evaluation, units without a ward pharmacist did not improve. Transcription errors significantly decreased in three units: gynaecology-urology (3.24% vs. 0.52%), orthopaedic (2% vs. 1.69%) and neurology-pneumology (2.81% vs. 2.02%). In dispensing, only units with the new protocol decreased their medication errors (1.77% vs. 1.24%). The participation of pharmacists in multidisciplinary teams and exhaustive protocols for dispensing medication were effective in detecting and decreasing medication errors in patients.

ISMP Medication Error Report Analysis

PubMed Central

Cohen, Michael R.; Smetzer, Judy L.

2017-01-01

These medication errors have occurred in health care facilities at least once. They will happen again—perhaps where you work. Through education and alertness of personnel and procedural safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them at your inservice training programs. Your assistance is required to continue this feature. The reports described here were received through the Institute for Safe Medication Practices (ISMP) Medication Errors Reporting Program. Any reports published by ISMP will be anonymous. Comments are also invited; the writers' names will be published if desired. ISMP may be contacted at the address shown below. Errors, close calls, or hazardous conditions may be reported directly to ISMP through the ISMP Web site (www.ismp.org), by calling 800-FAIL-SAFE, or via e-mail at ismpinfo@ismp.org. ISMP guarantees the confidentiality and security of the information received and respects reporters' wishes as to the level of detail included in publications. PMID:28179735

ISMP Medication Error Report Analysis

PubMed Central

Cohen, Michael R.; Smetzer, Judy L.

2017-01-01

These medication errors have occurred in health care facilities at least once. They will happen again—perhaps where you work. Through education and alertness of personnel and procedural safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them at your in-service training programs. Your assistance is required to continue this feature. The reports described here were received through the Institute for Safe Medication Practices (ISMP) Medication Errors Reporting Program. Any reports published by ISMP will be anonymous. Comments are also invited; the writers’ names will be published if desired. ISMP may be contacted at the address shown below. Errors, close calls, or hazardous conditions may be reported directly to ISMP through the ISMP Web site (www.ismp.org), by calling 800-FAIL-SAFE, or via e-mail at ismpinfo@ismp.org. ISMP guarantees the confidentiality and security of the information received and respects reporters’ wishes as to the level of detail included in publications. PMID:29276260

ISMP Medication Error Report Analysis

PubMed Central

Cohen, Michael R.; Smetzer, Judy L.

2016-01-01

These medication errors have occurred in health care facilities at least once. They will happen again—perhaps where you work. Through education and alertness of personnel and procedural safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them at your inservice training programs. Your assistance is required to continue this feature. The reports described here were received through the Institute for Safe Medication Practices (ISMP) Medication Errors Reporting Program. Any reports published by ISMP will be anonymous. Comments are also invited; the writers' names will be published if desired. ISMP may be contacted at the address shown below. Errors, close calls, or hazardous conditions may be reported directly to ISMP through the ISMP Web site (www.ismp.org), by calling 800-FAIL-SAFE, or via e-mail at ismpinfo@ismp.org. ISMP guarantees the confidentiality and security of the information received and respects reporters' wishes as to the level of detail included in publications. PMID:28057945

ISMP Medication Error Report Analysis

PubMed Central

Cohen, Michael R.; Smetzer, Judy L.

2016-01-01

ABSTRACT These medication errors have occurred in health care facilities at least once. They will happen again—perhaps where you work. Through education and alertness of personnel and procedural-safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them at your inservice training programs. Your assistance is required to continue this feature. The reports described here were receivedthrough the Institute for Safe Medication Practices (ISMP) Medication Errors Reporting Program. Any reports published by ISMP will be anonymous. Comments are also invited; the writers' names will be published if desired. ISMP may be contacted at the address shown below. Errors, close calls, or hazardous conditions may be reported directly to ISMP through the ISMP Web site (www.ismp.org), by calling 800-FAIL-SAFE, or via e-mail at ismpinfo@ismp.org. ISMP guarantees the confidentiality and security of the information received and respects reporters' wishes as to the level of detail included in publications. PMID:27928183

Precise Orbit Determination for GEOSAT Follow-On Using Satellite Laser Ranging Data and Intermission Altimeter Crossovers

NASA Technical Reports Server (NTRS)

Lemoine, Frank G.; Rowlands, David D.; Luthcke, Scott B.; Zelensky, Nikita P.; Chinn, Douglas S.; Pavlis, Despina E.; Marr, Gregory

2001-01-01

The US Navy's GEOSAT Follow-On Spacecraft was launched on February 10, 1998 with the primary objective of the mission to map the oceans using a radar altimeter. Following an extensive set of calibration campaigns in 1999 and 2000, the US Navy formally accepted delivery of the satellite on November 29, 2000. Satellite laser ranging (SLR) and Doppler (Tranet-style) beacons track the spacecraft. Although limited amounts of GPS data were obtained, the primary mode of tracking remains satellite laser ranging. The GFO altimeter measurements are highly precise, with orbit error the largest component in the error budget. We have tuned the non-conservative force model for GFO and the gravity model using SLR, Doppler and altimeter crossover data sampled over one year. Gravity covariance projections to 70x70 show the radial orbit error on GEOSAT was reduced from 2.6 cm in EGM96 to 1.3 cm with the addition of SLR, GFO/GFO and TOPEX/GFO crossover data. Evaluation of the gravity fields using SLR and crossover data support the covariance projections and also show a dramatic reduction in geographically-correlated error for the tuned fields. In this paper, we report on progress in orbit determination for GFO using GFO/GFO and TOPEX/GFO altimeter crossovers. We will discuss improvements in satellite force modeling and orbit determination strategy, which allows reduction in GFO radial orbit error from 10-15 cm to better than 5 cm.