Performance Analysis: Control of Hazardous Energy

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

De Grange, Connie E.; Freeman, Jeff W.; Kerr, Christine E.

2010-10-06

LLNL experienced 26 occurrences related to the control of hazardous energy from January 1, 2008 through August 2010. These occurrences were 17% of the total number of reported occurrences during this 32-month period. The Performance Analysis and Reporting Section of the Contractor Assurance Office (CAO) routinely analyzes reported occurrences and issues looking for patterns that may indicate changes in LLNL’s performance and early indications of performance trends. It became apparent through these analyses that LLNL might have experienced a change in the control of hazardous energy and that these occurrences should be analyzed in more detail to determine if themore » perceived change in performance was real, whether that change is significant and if the causes of the occurrences are similar. This report documents the results of this more detailed analysis.« less

Risky Decision Making Assessed With the Gambling Task in Adults with HIV

PubMed Central

Hardy, David J.; Hinkin, Charles H.; Castellon, Steven A.; Levine, Andrew J.; Lam, Mona N.

2010-01-01

Decision making was assessed using a laboratory gambling task in 67 adults with the Human Immunodeficiency Virus (HIV+) and in 19 HIV-seronegative (HIV−) control participants. Neurocognitive test performance across several domains was also analyzed to examine potential cognitive mechanisms of gambling task performance. As predicted, the HIV+ group performed worse on the gambling task, indicating greater risky decision making. Specifically, the HIV+ group selected more cards from the “risky” or disadvantageous deck that included relatively large payoffs but infrequent large penalties. The control group also selected such risky cards but quickly learned to avoid them. Exploratory analyses also indicated that in the HIV+ group, but not in the control group, gambling task performance was correlated with Stroop Interference performance and long delay free recall on the California Verbal Learning Test, suggesting the role of inhibitory processes and verbal memory in the poorer gambling task performance in HIV. These findings indicate the usefulness of the gambling task as a laboratory tool to examine risky decision making and cognition in the HIV population. PMID:16719628

Monitoring of International Space Station Telemetry Using Shewhart Control Charts

NASA Technical Reports Server (NTRS)

Fitch, Jeffery T.; Simon, Alan L.; Gouveia, John A.; Hillin, Andrew M.; Hernandez, Steve A.

2012-01-01

Shewhart control charts have been established as an expedient method for analyzing dynamic, trending data in order to identify anomalous subsystem performance as soon as such performance would exceed a statistically established baseline. Additionally, this leading indicator tool integrates a selection methodology that reduces false positive indications, optimizes true leading indicator events, minimizes computer processor unit duty cycles, and addresses human factor concerns (i.e., the potential for flight-controller data overload). This innovation leverages statistical process control, and provides a relatively simple way to allow flight controllers to focus their attention on subtle system changes that could lead to dramatic off-nominal system performance. Finally, this capability improves response time to potential hardware damage and/or crew injury, thereby improving space flight safety. Shewhart control charts require normalized data. However, the telemetry from the ISS Early External Thermal Control System (EETCS) was not normally distributed. A method for normalizing the data was implemented, as was a means of selecting data windows, the number of standard deviations (Sigma Level), the number of consecutive points out of limits (Sequence), and direction (increasing or decreasing trend data). By varying these options, and treating them like dial settings, the number of nuisance alerts and leading indicators were optimized. The goal was to capture all leading indicators while minimizing the number of nuisances. Lean Six Sigma (L6S) design of experiment methodologies were employed. To optimize the results, Perl programming language was used to automate the massive amounts of telemetry data, control chart plots, and the data analysis.

Executive functioning in preschool children: performance on A-not-B and other delayed response format tasks.

PubMed

Espy, K A; Kaufmann, P M; McDiarmid, M D; Glisky, M L

1999-11-01

The A-not-B (AB) task has been hypothesized to measure executive/frontal lobe function; however, the developmental and measurement characteristics of this task have not been investigated. Performances on AB and comparison tasks adapted from developmental and neuroscience literature was examined in 117 preschool children (ages 23-66 months). Age significantly predicted performance on AB, Delayed Alternation, Spatial Reversal, Color Reversal, and Self-Control tasks. A four-factor analytic model best fit task performance data. AB task indices loaded on two factors with measures from the Self-Control and Delayed Alternation tasks, respectively. AB indices did not load with those from the reversal tasks despite similarities in task administration and presumed cognitive demand (working memory). These results indicate that AB is sensitive to individual differences in age-related performance in preschool children and suggest that AB performance is related to both working memory and inhibition processes in this age range.

Aerobic Fitness and Cognitive Development: Event-Related Brain Potential and Task Performance Indices of Executive Control in Preadolescent Children

ERIC Educational Resources Information Center

Hillman, Charles H.; Buck, Sarah M.; Themanson, Jason R.; Pontifex, Matthew B.; Castelli, Darla M.

2009-01-01

The relationship between aerobic fitness and executive control was assessed in 38 higher- and lower-fit children (M[subscript age] = 9.4 years), grouped according to their performance on a field test of aerobic capacity. Participants performed a flanker task requiring variable amounts of executive control while event-related brain potential…

Facility versus unit level reporting of quality indicators in nursing homes when performance monitoring is the goal

PubMed Central

Norton, Peter G; Murray, Michael; Doupe, Malcolm B; Cummings, Greta G; Poss, Jeff W; Squires, Janet E; Teare, Gary F; Estabrooks, Carole A

2014-01-01

Objectives To demonstrate the benefit of defining operational management units in nursing homes and computing quality indicators on these units as well as on the whole facility. Design Calculation of adjusted Resident Assessment Instrument – Minimum Data Set 2.0 (RAI–MDS 2.0) quality indicators for: PRU05 (prevalence of residents with a stage 2–4 pressure ulcer), PAI0X (prevalence of residents with pain) and DRG01 (prevalence of residents receiving an antipsychotic with no diagnosis of psychosis), for quarterly assessments between 2007 and 2011 at unit and facility levels. Comparisons of these risk-adjusted quality indicators using statistical process control (control charts). Setting A representative sample of 30 urban nursing homes in the three Canadian Prairie Provinces. Measurements Explicit decision rules were developed and tested to determine whether the control charts demonstrated improving, worsening, unchanging or unclassifiable trends over the time period. Unit and facility performance were compared. Results In 48.9% of the units studied, unit control chart performance indicated different changes in quality over the reporting period than did the facility chart. Examples are provided to illustrate that these differences lead to quite different quality interventions. Conclusions Our results demonstrate the necessity of considering facility-level and unit-level measurement when calculating quality indicators derived from the RAI–MDS 2.0 data, and quite probably from any RAI measures. PMID:24523428

From Rationale to Results: Implementing Performance Indicators in a Public Library.

ERIC Educational Resources Information Center

Alston, Ruth

This paper describes the theoretical design and practical implementation of a set of performance indicators in a public library system in London (England). Bromley Libraries has 15 branch libraries and serves 300,000 people. The need for improved management control by assessing performance and monitoring progress, library restructuring, and…

Multisensory Integration Strategy for Modality-Specific Loss of Inhibition Control in Older Adults.

PubMed

Lee, Ahreum; Ryu, Hokyoung; Kim, Jae-Kwan; Jeong, Eunju

2018-04-11

Older adults are known to have lesser cognitive control capability and greater susceptibility to distraction than young adults. Previous studies have reported age-related problems in selective attention and inhibitory control, yielding mixed results depending on modality and context in which stimuli and tasks were presented. The purpose of the study was to empirically demonstrate a modality-specific loss of inhibitory control in processing audio-visual information with ageing. A group of 30 young adults (mean age = 25.23, Standar Desviation (SD) = 1.86) and 22 older adults (mean age = 55.91, SD = 4.92) performed the audio-visual contour identification task (AV-CIT). We compared performance of visual/auditory identification (Uni-V, Uni-A) with that of visual/auditory identification in the presence of distraction in counterpart modality (Multi-V, Multi-A). The findings showed a modality-specific effect on inhibitory control. Uni-V performance was significantly better than Multi-V, indicating that auditory distraction significantly hampered visual target identification. However, Multi-A performance was significantly enhanced compared to Uni-A, indicating that auditory target performance was significantly enhanced by visual distraction. Additional analysis showed an age-specific effect on enhancement between Uni-A and Multi-A depending on the level of visual inhibition. Together, our findings indicated that the loss of visual inhibitory control was beneficial for the auditory target identification presented in a multimodal context in older adults. A likely multisensory information processing strategy in the older adults was further discussed in relation to aged cognition.

Conjugating binary systems for spacecraft thermal control

NASA Technical Reports Server (NTRS)

Grodzka, Philomena G.; Dean, William G.; Sisk, Lori A.; Karu, Zain S.

1989-01-01

The materials search was directed to liquid pairs which can form hydrogen bonds of just the right strength, i.e., strong enough to give a high heat of mixing, but weak enough to enable phase change to occur. The cursory studies performed in the area of additive effects indicate that Conjugating Binary (CB) performance can probably be fine-tuned by this means. The Fluid Loop Test Systems (FLTS) tests of candidate CBs indicate that the systems Triethylamine (TEA)/water and propionaldehyde/water show close to the ideal, reversible behavior, at least initially. The Quick Screening Tests QSTs and FLTS tests, however, both suffer from rather severe static due either to inadequate stirring or temperature control. Thus it is not possible to adequately evaluate less than ideal CB performers. Less than ideal performers, it should be noted, may have features that make them better practical CBs than ideal performers. Improvement of the evaluation instrumentation is thus indicated.

Statistical Process Control: A Quality Tool for a Venous Thromboembolic Disease Registry.

PubMed

Posadas-Martinez, Maria Lourdes; Rojas, Liliana Paloma; Vazquez, Fernando Javier; De Quiros, Fernan Bernaldo; Waisman, Gabriel Dario; Giunta, Diego Hernan

2016-01-01

We aim to describe Statistical Control Process as a quality tool for the Institutional Registry of Venous Thromboembolic Disease (IRTD), a registry developed in a community-care tertiary hospital in Buenos Aires, Argentina. The IRTD is a prospective cohort. The process of data acquisition began with the creation of a computerized alert generated whenever physicians requested imaging or laboratory study to diagnose venous thromboembolism, which defined eligible patients. The process then followed a structured methodology for patient's inclusion, evaluation, and posterior data entry. To control this process, process performance indicators were designed to be measured monthly. These included the number of eligible patients, the number of included patients, median time to patient's evaluation, and percentage of patients lost to evaluation. Control charts were graphed for each indicator. The registry was evaluated in 93 months, where 25,757 patients were reported and 6,798 patients met inclusion criteria. The median time to evaluation was 20 hours (SD, 12) and 7.7% of the total was lost to evaluation. Each indicator presented trends over time, caused by structural changes and improvement cycles, and therefore the central limit suffered inflexions. Statistical process control through process performance indicators allowed us to control the performance of the registry over time to detect systematic problems. We postulate that this approach could be reproduced for other clinical registries.

An optimization-based integrated controls-structures design methodology for flexible space structures

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.; Joshi, Suresh M.; Armstrong, Ernest S.

1993-01-01

An approach for an optimization-based integrated controls-structures design is presented for a class of flexible spacecraft that require fine attitude pointing and vibration suppression. The integrated design problem is posed in the form of simultaneous optimization of both structural and control design variables. The approach is demonstrated by application to the integrated design of a generic space platform and to a model of a ground-based flexible structure. The numerical results obtained indicate that the integrated design approach can yield spacecraft designs that have substantially superior performance over a conventional design wherein the structural and control designs are performed sequentially. For example, a 40-percent reduction in the pointing error is observed along with a slight reduction in mass, or an almost twofold increase in the controlled performance is indicated with more than a 5-percent reduction in the overall mass of the spacecraft (a reduction of hundreds of kilograms).

Optimisation of active suspension control inputs for improved performance of active safety systems

NASA Astrophysics Data System (ADS)

Čorić, Mirko; Deur, Joško; Xu, Li; Tseng, H. Eric; Hrovat, Davor

2018-01-01

A collocation-type control variable optimisation method is used to investigate the extent to which the fully active suspension (FAS) can be applied to improve the vehicle electronic stability control (ESC) performance and reduce the braking distance. First, the optimisation approach is applied to the scenario of vehicle stabilisation during the sine-with-dwell manoeuvre. The results are used to provide insights into different FAS control mechanisms for vehicle performance improvements related to responsiveness and yaw rate error reduction indices. The FAS control performance is compared to performances of the standard ESC system, optimal active brake system and combined FAS and ESC configuration. Second, the optimisation approach is employed to the task of FAS-based braking distance reduction for straight-line vehicle motion. Here, the scenarios of uniform and longitudinally or laterally non-uniform tyre-road friction coefficient are considered. The influences of limited anti-lock braking system (ABS) actuator bandwidth and limit-cycle ABS behaviour are also analysed. The optimisation results indicate that the FAS can provide competitive stabilisation performance and improved agility when compared to the ESC system, and that it can reduce the braking distance by up to 5% for distinctively non-uniform friction conditions.

Temporal guidance of musicians' performance movement is an acquired skill.

PubMed

Rodger, M W M; O'Modhrain, S; Craig, C M

2013-04-01

The ancillary (non-sounding) body movements made by expert musicians during performance have been shown to indicate expressive, emotional, and structural features of the music to observers, even if the sound of the performance is absent. If such ancillary body movements are a component of skilled musical performance, then it should follow that acquiring the temporal control of such movements is a feature of musical skill acquisition. This proposition is tested using measures derived from a theory of temporal guidance of movement, "General Tau Theory" (Lee in Ecol Psychol 10:221-250, 1998; Lee et al. in Exp Brain Res 139:151-159, 2001), to compare movements made during performances of intermediate-level clarinetists before and after learning a new piece of music. Results indicate that the temporal control of ancillary body movements made by participants was stronger in performances after the music had been learned and was closer to the measures of temporal control found for an expert musician's movements. These findings provide evidence that the temporal control of musicians' ancillary body movements develops with musical learning. These results have implications for other skillful behaviors and nonverbal communication.

Performance Indicators and Rational Management Tools: A Comparative Assessment of Projects in North America and Europe. AIR 1993 Annual Forum Paper.

ERIC Educational Resources Information Center

Nedwek, Brian P.; Neal, John E.

This study developed a classification scheme to critically compare performance assessment projects at higher education universities in North America and Europe. Performance indicators and assessment initiatives were compared using nine basic dimensions: (1) locus of control, (2) degree of governmental involvement, (3) focus of performance…

A Model-Based Approach to Predicting Graduate-Level Performance Using Indicators of Undergraduate-Level Performance

ERIC Educational Resources Information Center

Zimmermann, Judith; Brodersen, Kay H.; Heinimann, Hans R.; Buhmann, Joachim M.

2015-01-01

The graduate admissions process is crucial for controlling the quality of higher education, yet, rules-of-thumb and domain-specific experiences often dominate evidence-based approaches. The goal of the present study is to dissect the predictive power of undergraduate performance indicators and their aggregates. We analyze 81 variables in 171…

Perceived academic performance, self-esteem and locus of control as indicators of need for assessment of adolescent suicide risk: implications for teachers.

PubMed

Martin, Graham; Richardson, Angela S; Bergen, Helen A; Roeger, Leigh; Allison, Stephen

2005-02-01

There is currently a need for research into indicators that could be used by non-clinical professionals working with young people, to inform the need for referral for further clinical assessment of those at risk of suicide. Participants of this repeated measures longitudinal study, were 2603, 2485, and 2246 school students aged 13, 14, and 15, respectively, from 27 South Australian Schools. Perceived academic performance, self-esteem and locus of control are significantly associated with suicidality. Further, logistic regression of longitudinal results suggests that perceived academic performance, over and above self-esteem and locus of control, in some instances, is a good long-term predictor of suicidality.

How different is cancer control across Canada? Comparing performance indicators for prevention, screening, diagnosis, and treatment.

PubMed

Rahal, R; Chadder, J; DeCaria, K; Lockwood, G; Bryant, H

2017-04-01

Meaningful performance measures are an important part of the toolkit for health system improvement. The Canadian Partnership Against Cancer has been reporting on pan-Canadian cancer system performance indicators since 2009-work that has led to the availability of standardized measures that can help to shed light on the extent of variation and opportunities for quality improvement across the country. Those measures include a core set of system indicators ranging from prevention and screening, through diagnosis and treatment, to survivorship and end-of-life care. Key indicators were calculated and graphed, showing the range from worst to best result for the provinces and territories included in the data. There were often significant differences in cancer system performance between provinces and territories. For example, smoking prevalence rates ranged from 14% to 62%. The 90th percentile wait times from an abnormal breast screen to resolution (without biopsy) ranged from 4 weeks to 8 weeks. The percentage of breast cancer resections that used breast-conserving surgery rather than mastectomy ranged from 38% to 75%. Clinical trial participation rates for adults ranged from 0.2% to 6.6%. Variations in performance indicators between Canadian jurisdictions suggest potential differences in the planning and delivery of cancer control services and in clinical practice patterns and patient outcomes. Understanding sources of variation can help to identify opportunities for improvements in the quality and outcomes of cancer control service delivery in each province and territory.

Multisensory Integration Strategy for Modality-Specific Loss of Inhibition Control in Older Adults

PubMed Central

Ryu, Hokyoung; Kim, Jae-Kwan; Jeong, Eunju

2018-01-01

Older adults are known to have lesser cognitive control capability and greater susceptibility to distraction than young adults. Previous studies have reported age-related problems in selective attention and inhibitory control, yielding mixed results depending on modality and context in which stimuli and tasks were presented. The purpose of the study was to empirically demonstrate a modality-specific loss of inhibitory control in processing audio-visual information with ageing. A group of 30 young adults (mean age = 25.23, Standard Deviation (SD) = 1.86) and 22 older adults (mean age = 55.91, SD = 4.92) performed the audio-visual contour identification task (AV-CIT). We compared performance of visual/auditory identification (Uni-V, Uni-A) with that of visual/auditory identification in the presence of distraction in counterpart modality (Multi-V, Multi-A). The findings showed a modality-specific effect on inhibitory control. Uni-V performance was significantly better than Multi-V, indicating that auditory distraction significantly hampered visual target identification. However, Multi-A performance was significantly enhanced compared to Uni-A, indicating that auditory target performance was significantly enhanced by visual distraction. Additional analysis showed an age-specific effect on enhancement between Uni-A and Multi-A depending on the level of visual inhibition. Together, our findings indicated that the loss of visual inhibitory control was beneficial for the auditory target identification presented in a multimodal context in older adults. A likely multisensory information processing strategy in the older adults was further discussed in relation to aged cognition. PMID:29641462

Evaluation of control and display configurations for helicopter shipboard operations

NASA Technical Reports Server (NTRS)

Paulk, C. H., Jr.; Donley, S. T.; Hollis, M. K.

1983-01-01

A simulation evaluation of several approach and landing flight-control configurations and of two out-of-the-cockpit display devices (a head-up display and a helmet-mounted display) was performed for the task of landing a helicopter on a destroyer in adverse weather. The results indicated that the ship airwake turbulence was the most significant environmental variable affecting hover performance. In addition, to achieve adequate landing performance, attitude-command control compensation was required for the pilot regardless of the display used. For improved performance with reduced pilot effort, a velocity-command, position-hold control system was desired.

Usefulness and Validity of Continuous Performance Tests in the Diagnosis of Attention-Deficit Hyperactivity Disorder Children.

PubMed

Berger, Itai; Slobodin, Ortal; Cassuto, Hanoch

2017-02-01

Despite the popularity of continuous performance tests (CPT) in supporting the diagnostic procedure of attention-deficit hyperactivity disorder (ADHD), these measures are still controversial mainly due to limited sensitivity, specificity, and ecological validity. Thus, there continues to be a need for further validation of these objective attention measures. The purpose of this study was to evaluate the usefulness of a CPT that includes environmental distracting stimuli, in supporting the diagnosis of ADHD in children. Participants were 798 children aged 7-12 years (493 boys and 305 girls). The ADHD group included 339 children, whereas the control group included 459 children without ADHD. The study employed the MOXO-CPT, which incorporates visual and auditory stimuli serving as environmental distractors. Compared to their unaffected peers, children with ADHD received significantly lower scores in all 4 CPT indices: attention, timing, hyperactivity, and impulsivity. Specifically, ADHD children were less attended to the stimuli and performed fewer reactions on accurate timing. Furthermore, children with ADHD performed significantly more impulsive and hyperactive responses than controls. Receiver operating characteristic analysis revealed fair to excellent diagnostic ability of all CPT indices except impulsivity, which showed poor ability to distinguish ADHD children from controls. The test's total score yielded excellent diagnostic performance. MOXO-CPT consistently distinguished between children with ADHD and their unaffected peers, so that children with ADHD performed worse than controls in all study indices. Integration of CPT indices improves the diagnostic capacity of ADHD and may better reflect the complexity and heterogeneity of ADHD. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Impact of Social Pressure and Monetary Incentive on Cognitive Control.

PubMed

Ličen, Mina; Hartmann, Frank; Repovš, Grega; Slapničar, Sergeja

2016-01-01

We compare the effects of two prominent organizational control mechanisms-social pressure and monetary incentive-on cognitive control. Cognitive control underlies the human ability to regulate thoughts and actions in the pursuit of behavioral goals. Previous studies show that monetary incentives can contribute to goal-oriented behavior by activating proactive control. There is, however, much less evidence of how social pressure affects cognitive control and task performance. In a within-subject experimental design, we tested 47 subjects performing the AX-CPT task to compare the activation of cognitive control modes under social pressure and monetary incentive beyond mere instructions to perform better. Our results indicate that instructing participants to improve their performance on its own leads to a significant shift from a reactive to a proactive control mode and that both social pressure and monetary incentive further enhance performance.

Aircraft symmetric flight optimization. [gradient techniques for supersonic aircraft control

NASA Technical Reports Server (NTRS)

Falco, M.; Kelley, H. J.

1973-01-01

Review of the development of gradient techniques and their application to aircraft optimal performance computations in the vertical plane of flight. Results obtained using the method of gradients are presented for attitude- and throttle-control programs which extremize the fuel, range, and time performance indices subject to various trajectory and control constraints, including boundedness of engine throttle control. A penalty function treatment of state inequality constraints which generally appear in aircraft performance problems is outlined. Numerical results for maximum-range, minimum-fuel, and minimum-time climb paths for a hypothetical supersonic turbojet interceptor are presented and discussed. In addition, minimum-fuel climb paths subject to various levels of ground overpressure intensity constraint are indicated for a representative supersonic transport. A variant of the Gel'fand-Tsetlin 'method of ravines' is reviewed, and two possibilities for further development of continuous gradient processes are cited - namely, a projection version of conjugate gradients and a curvilinear search.

Relationship between antigravity control and postural control in young children.

PubMed

Sellers, J S

1988-04-01

The purposes of this study were 1) to determine the relationship between antigravity control (supine flexion and prone extension) and postural control (static and dynamic balance), 2) to determine the quality of antigravity and postural control, and 3) to determine whether sex and ethnic group differences correlate with differences in antigravity control and postural control in young children. I tested 107 black, Hispanic, and Caucasian children in a Head Start program, with a mean age of 61 months. The study results showed significant relationships between antigravity control and postural control. Subjects' supine flexion performance was significantly related to the quantity and quality of their static and dynamic balance performance, whereas prone extension performance was related only to the quality of dynamic balance performance. Quality scale measurements (r = .90) indicated that the children in this study had not yet developed full antigravity or postural control. The study results revealed differences between sexes in the quality of static balance and prone extension performance and ethnic differences in static balance, dynamic balance, and prone extension performance.

Robust tracking control of a magnetically suspended rigid body

NASA Technical Reports Server (NTRS)

Lim, Kyong B.; Cox, David E.

1994-01-01

This study is an application of H-infinity and micro-synthesis for designing robust tracking controllers for the Large Angle Magnetic Suspension Test Facility. The modeling, design, analysis, simulation, and testing of a control law that guarantees tracking performance under external disturbances and model uncertainties is investigated. The type of uncertainties considered and the tracking performance metric used is discussed. This study demonstrates the tradeoff between tracking performance at low frequencies and robustness at high frequencies. Two sets of controllers were designed and tested. The first set emphasized performance over robustness, while the second set traded off performance for robustness. Comparisons of simulation and test results are also included. Current simulation and experimental results indicate that reasonably good robust tracking performance can be attained for this system using multivariable robust control approach.

Sliding mode control of magnetic suspensions for precision pointing and tracking applications

NASA Technical Reports Server (NTRS)

Misovec, Kathleen M.; Flynn, Frederick J.; Johnson, Bruce G.; Hedrick, J. Karl

1991-01-01

A recently developed nonlinear control method, sliding mode control, is examined as a means of advancing the achievable performance of space-based precision pointing and tracking systems that use nonlinear magnetic actuators. Analytic results indicate that sliding mode control improves performance compared to linear control approaches. In order to realize these performance improvements, precise knowledge of the plant is required. Additionally, the interaction of an estimating scheme and the sliding mode controller has not been fully examined in the literature. Estimation schemes were designed for use with this sliding mode controller that do not seriously degrade system performance. The authors designed and built a laboratory testbed to determine the feasibility of utilizing sliding mode control in these types of applications. Using this testbed, experimental verification of the authors' analyses is ongoing.

An Investigation of the Relationship Between Chronological Age and Indicators of Job Performance for Incumbent Air Traffic Control Specialists

DOT National Transportation Integrated Search

1999-06-01

Over the last few decades, researchers have consistently found a negative relationship between the age of air traffic control specialists (ATCSs) and both training success and ratings of job performance. As more ATCSs reach retirement age and the Fed...

10 CFR 74.59 - Quality assurance and accounting requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... analyses and evaluations of the design, installation, preoperational tests, calibration, and operation of... performed at a pre-determined frequency, indicate a need for recalibration. Calibrations and tests must be... necessary for performance of the material control tests required by § 74.53(b). (e) Measurement control. The...

10 CFR 74.59 - Quality assurance and accounting requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... analyses and evaluations of the design, installation, preoperational tests, calibration, and operation of... performed at a pre-determined frequency, indicate a need for recalibration. Calibrations and tests must be... necessary for performance of the material control tests required by § 74.53(b). (e) Measurement control. The...

The Impact of Social Pressure and Monetary Incentive on Cognitive Control

PubMed Central

Ličen, Mina; Hartmann, Frank; Repovš, Grega; Slapničar, Sergeja

2016-01-01

We compare the effects of two prominent organizational control mechanisms—social pressure and monetary incentive—on cognitive control. Cognitive control underlies the human ability to regulate thoughts and actions in the pursuit of behavioral goals. Previous studies show that monetary incentives can contribute to goal-oriented behavior by activating proactive control. There is, however, much less evidence of how social pressure affects cognitive control and task performance. In a within-subject experimental design, we tested 47 subjects performing the AX-CPT task to compare the activation of cognitive control modes under social pressure and monetary incentive beyond mere instructions to perform better. Our results indicate that instructing participants to improve their performance on its own leads to a significant shift from a reactive to a proactive control mode and that both social pressure and monetary incentive further enhance performance. PMID:26903901

An ex ante control chart for project monitoring using earned duration management observations

NASA Astrophysics Data System (ADS)

Mortaji, Seyed Taha Hossein; Noori, Siamak; Noorossana, Rassoul; Bagherpour, Morteza

2017-12-01

In the past few years, there has been an increasing interest in developing project control systems. The primary purpose of such systems is to indicate whether the actual performance is consistent with the baseline and to produce a signal in the case of non-compliance. Recently, researchers have shown an increased interest in monitoring project's performance indicators, by plotting them on the Shewhart-type control charts over time. However, these control charts are fundamentally designed for processes and ignore project-specific dynamics, which can lead to weak results and misleading interpretations. By paying close attention to the project baseline schedule and using statistical foundations, this paper proposes a new ex ante control chart which discriminates between acceptable (as-planned) and non-acceptable (not-as-planned) variations of the project's schedule performance. Such control chart enables project managers to set more realistic thresholds leading to a better decision making for taking corrective and/or preventive actions. For the sake of clarity, an illustrative example has been presented to show how the ex ante control chart is constructed in practice. Furthermore, an experimental investigation has been set up to analyze the performance of the proposed control chart. As expected, the results confirm that, when a project starts to deflect significantly from the project's baseline schedule, the ex ante control chart shows a respectable ability to detect and report right signals while avoiding false alarms.

Intelligent Performance Analysis with a Natural Language Interface

NASA Astrophysics Data System (ADS)

Juuso, Esko K.

2017-09-01

Performance improvement is taken as the primary goal in the asset management. Advanced data analysis is needed to efficiently integrate condition monitoring data into the operation and maintenance. Intelligent stress and condition indices have been developed for control and condition monitoring by combining generalized norms with efficient nonlinear scaling. These nonlinear scaling methodologies can also be used to handle performance measures used for management since management oriented indicators can be presented in the same scale as intelligent condition and stress indices. Performance indicators are responses of the process, machine or system to the stress contributions analyzed from process and condition monitoring data. Scaled values are directly used in intelligent temporal analysis to calculate fluctuations and trends. All these methodologies can be used in prognostics and fatigue prediction. The meanings of the variables are beneficial in extracting expert knowledge and representing information in natural language. The idea of dividing the problems into the variable specific meanings and the directions of interactions provides various improvements for performance monitoring and decision making. The integrated temporal analysis and uncertainty processing facilitates the efficient use of domain expertise. Measurements can be monitored with generalized statistical process control (GSPC) based on the same scaling functions.

[Consolidation of international guidelines for the management of canine populations in urban areas and proposal of performance indicators].

PubMed

Garcia, Rita de Cassia Maria; Calderón, Néstor; Ferreira, Fernando

2012-08-01

The objective of this study is to propose a generic program for the management of urban canine populations with suggestion of performance indicators. The following international guidelines on canine population management were revised and consolidated: World Health Organization, World Organisation for Animal Health, World Society for the Protection of Animals, International Companion Animal Management Coalition, and the Food and Agriculture Organization. Management programs should cover: situation diagnosis, including estimates of population size; social participation with involvement of various sectors in the planning and execution of strategies; educational actions to promote humane values, animal welfare, community health, and responsible ownership (through purchase or adoption); environmental and waste management to eliminate sources of food and shelter; registration and identification of animals; animal health care, reproductive control; prevention and control of zoonoses; control of animal commerce; management of animal behavior and adequate solutions for abandoned animals; and laws regulating responsible ownership, prevention of abandonment and zoonoses. To monitor these actions, four groups of indicators are suggested: animal population indicators, human/animal interaction indicators, public service indicators, and zoonosis indicators. The management of stray canine populations requires political, sanitary, ethologic, ecologic, and humanitarian strategies that are socially acceptable and environmentally sustainable. Such measures must also include the control of zoonoses such as rabies and leishmaniasis, considering the concept of "one health," which benefits both the animals and people in the community.

Long-lasting effects of performance-contingent unconscious and conscious reward incentives during cued task-switching.

PubMed

Capa, Rémi L; Bouquet, Cédric A; Dreher, Jean-Claude; Dufour, André

2013-01-01

Motivation is often thought to interact consciously with executive control, although recent studies have indicated that motivation can also be unconscious. To date, however, the effects of unconscious motivation on high-order executive control functions have not been explored. Only a few studies using subliminal stimuli (i.e., those not related to motivation, such as an arrow to prime a response) have reported short-lived effects on high-order executive control functions. Here, building on research on unconscious motivation, in which a behavior of perseverance is induced to attain a goal, we hypothesized that subliminal motivation can have long-lasting effects on executive control processes. We investigated the impact of unconscious/conscious monetary reward incentives on evoked potentials and neural activity dynamics during cued task-switching performance. Participants performed long runs of task-switching. At the beginning of each run, a reward (50 cents or 1 cent) was displayed, either subliminally or supraliminally. Participants earned the reward contingent upon their correct responses to each trial of the run. A higher percentage of runs was achieved with higher (conscious and unconscious) than lower rewards, indicating that unconscious high rewards have long-lasting behavioral effects. Event-related potential (ERP) results indicated that unconscious and conscious rewards influenced preparatory effort in task preparation, as suggested by a greater fronto-central contingent negative variation (CNV) starting at cue-onset. However, a greater parietal P3 associated with better reaction times (RTs) was observed only under conditions of conscious high reward, suggesting a larger amount of working memory invested during task performance. Together, these results indicate that unconscious and conscious motivations are similar at early stages of task-switching preparation but differ during task performance. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of feedback interventions for improving the quality assurance of cancer screening in Japan: study design and report of the baseline survey.

PubMed

Machii, Ryoko; Saika, Kumiko; Higashi, Takahiro; Aoki, Ayako; Hamashima, Chisato; Saito, Hiroshi

2012-02-01

The importance of quality assurance in cancer screening has recently gained increasing attention in Japan. To evaluate and improve quality, checklists and process indicators have been developed. To explore effective methods of enhancing quality in cancer screening, we started a randomized control study of the methods of evaluation and feedback for cancer control from 2009 to 2014. We randomly assigned 1270 municipal governments, equivalent to 71% of all Japanese municipal governments that performed screening programs, into three groups. The high-intensity intervention groups (n = 425) were individually evaluated using both checklist performance and process indicator values, while the low-intensity intervention groups (n= 421) were individually evaluated on the basis of only checklist performance. The control group (n = 424) received only a basic report that included the national average of checklist performance scores. We repeated the survey for each municipality's quality assurance activity performance using checklists and process indicators. In this paper, we report our study design and the result of the baseline survey. The checklist adherence rates were especially low in the checklist elements related to invitation of individuals, detailed monitoring of process indicators such as cancer detection rates according to screening histories and appropriate selection of screening facilities. Screening rate and percentage of examinees who underwent detailed examination tended to be lower for large cities when compared with smaller cities for all cancer sites. The performance of the Japanese cancer screening program in 2009 was identified for the first time.

Study on the application of NASA energy management techniques for control of a terrestrial solar water heating system

NASA Technical Reports Server (NTRS)

Swanson, T. D.; Ollendorf, S.

1979-01-01

This paper addresses the potential for enhanced solar system performance through sophisticated control of the collector loop flow rate. Computer simulations utilizing the TRNSYS solar energy program were performed to study the relative effect on system performance of eight specific control algorithms. Six of these control algorithms are of the proportional type: two are concave exponentials, two are simple linear functions, and two are convex exponentials. These six functions are typical of what might be expected from future, more advanced, controllers. The other two algorithms are of the on/off type and are thus typical of existing control devices. Results of extensive computer simulations utilizing actual weather data indicate that proportional control does not significantly improve system performance. However, it is shown that thermal stratification in the liquid storage tank may significantly improve performance.

Alcohol effects on simulated driving performance and self-perceptions of impairment in DUI offenders

PubMed Central

Van Dyke, Nicholas; Fillmore, Mark T.

2014-01-01

Drivers with a history of driving under the influence (DUI) of alcohol self-report heightened impulsivity and display reckless driving behaviors as indicated by increased rates of vehicle crashes, moving violations, and traffic tickets. Such poor behavioral self-regulation could also increase sensitivity to the disruptive effects of alcohol on driving performance. The present study examined the degree to which DUI drivers display an increased sensitivity to the acute impairing effects of alcohol on simulated driving performance and overestimate their driving fitness following alcohol consumption. Adult drivers with a history of DUI and a demographically-matched group of drivers with no history of DUI (controls) were tested following a 0.65 g/kg alcohol and a placebo. Results indicated that alcohol impaired several measures of driving performance and there was no difference between DUI offenders and controls in these impairments. However, following alcohol DUI drivers self-reported a greater ability and willingness to drive compared with controls. These findings indicate that drivers with a history of DUI might perceive themselves as more fit to drive after drinking which could play an important role in their decisions to drink and drive. PMID:25347077

Alcohol effects on simulated driving performance and self-perceptions of impairment in DUI offenders.

PubMed

Van Dyke, Nicholas; Fillmore, Mark T

2014-12-01

Drivers with a history of driving under the influence (DUI) of alcohol self-report heightened impulsivity and display reckless driving behaviors as indicated by increased rates of vehicle crashes, moving violations, and traffic tickets. Such poor behavioral self-regulation could also increase sensitivity to the disruptive effects of alcohol on driving performance. The present study examined the degree to which DUI drivers display an increased sensitivity to the acute impairing effects of alcohol on simulated driving performance and overestimate their driving fitness following alcohol consumption. Adult drivers with a history of DUI and a demographically matched group of drivers with no history of DUI (controls) were tested following a 0.65 g/kg alcohol and a placebo. Results indicated that alcohol impaired several measures of driving performance, and there was no difference between DUI offenders and controls in these impairments. However, following alcohol, DUI drivers self-reported a greater ability and willingness to drive compared with controls. These findings indicate that drivers with a history of DUI might perceive themselves as more fit to drive after drinking, which could play an important role in their decisions to drink and drive. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Application of gain scheduling to the control of batch bioreactors

NASA Technical Reports Server (NTRS)

Cardello, Ralph; San, Ka-Yiu

1987-01-01

The implementation of control algorithms to batch bioreactors is often complicated by the inherent variations in process dynamics during the course of fermentation. Such a wide operating range may render the performance of fixed gain PID controllers unsatisfactory. In this work, a detailed study on the control of batch fermentation is performed. Furthermore, a simple batch controller design is proposed which incorporates the concept of gain-scheduling, a subclass of adaptive control, with oxygen uptake rate as an auxiliary variable. The control of oxygen tension in the biorector is used as a vehicle to convey the proposed idea, analysis and results. Simulation experiments indicate significant improvement in controller performance can be achieved by the proposed approach even in the presence of measurement noise.

New indicators proposed to assess tuberculosis control and elimination in Cuba.

PubMed

González, Edilberto R; Armas, Luisa

2012-10-01

Following 48 years of successful operation of the National Tuberculosis Control Program, Cuban health authorities have placed tuberculosis elimination on the agenda. To this end some tuberculosis control processes and their indicators need redesigned and new ones introduced, related to: number and proportion of suspected tuberculosis cases among vulnerable population groups; tuberculosis suspects with sputum microscopy and culture results useful for diagnosis (interpretable); and number of identified contacts of reported tuberculosis cases who were fully investigated. Such new indicators have been validated and successfully implemented in all provinces (2011-12) and are in the approval pipeline for generalized use in the National Tuberculosis Control Program. These indicators complement existing criteria for quality of case detection and support more comprehensive program performance assessment.

The Effect of Conscious Control on Handwriting in Children with Attention Deficit Hyperactivity Disorder

ERIC Educational Resources Information Center

Tucha, Oliver; Lange, Klaus W.

2005-01-01

Two experiments were performed regarding the effect of conscious control on handwriting fluency in healthy adults and ADHD children. First, 26 healthy students were asked to write a sentence under different conditions. The results indicate that automated handwriting movements are independent from visual feedback. Second, the writing performance of…

Comprehension of handwriting development: Pen-grip kinetics in handwriting tasks and its relation to fine motor skills among school-age children.

PubMed

Lin, Yu-Chen; Chao, Yen-Li; Wu, Shyi-Kuen; Lin, Ho-Hsio; Hsu, Chieh-Hsiang; Hsu, Hsiao-Man; Kuo, Li-Chieh

2017-10-01

Numerous tools have been developed to evaluate handwriting performances by analysing written products. However, few studies have directly investigated kinetic performances of digits when holding a pen. This study thus attempts to investigate pen-grip kinetics during writing tasks of school-age children and explore the relationship between the kinetic factors and fine motor skills. This study recruited 181 children aged from 5 to 12 years old and investigated the effects of age on handwriting kinetics and the relationship between these and fine motor skills. The forces applied from the digits and pen-tip were measured during writing tasks via a force acquisition pen, and the children's fine motor performances were also evaluated. The results indicate that peak force and average force might not be direct indicators of handwriting performance for normally developing children at this age. Younger children showed larger force variation and lower adjustment frequency during writing, which might indicate they had poorer force control than the older children. Force control when handling a pen is significantly correlated with fine motor performance, especially in relation to the manual dexterity. A novel system is proposed for analysing school-age children's force control while handwriting. We observed the development of force control in relation to pen grip among the children with different ages in this study. The findings suggested that manipulation skill may be crucial when children are establishing their handwriting capabilities. © 2017 Occupational Therapy Australia.

Mechanical problem-solving strategies in left-brain damaged patients and apraxia of tool use.

PubMed

Osiurak, François; Jarry, Christophe; Lesourd, Mathieu; Baumard, Josselin; Le Gall, Didier

2013-08-01

Left brain damage (LBD) can impair the ability to use familiar tools (apraxia of tool use) as well as novel tools to solve mechanical problems. Thus far, the emphasis has been placed on quantitative analyses of patients' performance. Nevertheless, the question still to be answered is, what are the strategies employed by those patients when confronted with tool use situations? To answer it, we asked 16 LBD patients and 43 healthy controls to solve mechanical problems by means of several potential tools. To specify the strategies, we recorded the time spent in performing four kinds of action (no manipulation, tool manipulation, box manipulation, and tool-box manipulation) as well as the number of relevant and irrelevant tools grasped. We compared LBD patients' performance with that of controls who encountered difficulties with the task (controls-) or not (controls+). Our results indicated that LBD patients grasped a higher number of irrelevant tools than controls+ and controls-. Concerning time allocation, controls+ and controls- spent significantly more time in performing tool-box manipulation than LBD patients. These results are inconsistent with the possibility that LBD patients could engage in trial-and-error strategies and, rather, suggest that they tend to be perplexed. These findings seem to indicate that the inability to reason about the objects' physical properties might prevent LBD patients from following any problem-solving strategy. Copyright © 2013 Elsevier Ltd. All rights reserved.

Examining the Dimensionality of Effortful Control in Preschool Children and Its Relation to Academic and Socioemotional Indicators

ERIC Educational Resources Information Center

Allan, Nicholas P.; Lonigan, Christopher J.

2011-01-01

Effortful control (EC) is an important developmental construct, associated with socioemotional growth, academic performance, and psychopathology. EC is defined as the ability to execute goal-directed behavior to inhibit or delay a prepotent response in favor of a subdominant response. Extant research indicates that EC may be multidimensional.…

Influence of light-sources and photoperiod on growth performance, carcass characteristics and health indices of broilers grown to heavy weights

USDA-ARS?s Scientific Manuscript database

Effects of light sources and photoperiod on growth performance, carcass characteristics and health indices of broilers were investigated in 4 trials. In each trial, 720 1 d old Ross × Ross 708 chicks were equally and randomly distributed into 12 environmentally-controlled rooms (30 males/30 females ...

Primary Health Care and tuberculosis: services evaluation.

PubMed

Wysocki, Anneliese Domingues; Ponce, Maria Amélia Zanon; Brunello, Maria Eugênia Firmino; Beraldo, Aline Ale; Vendramini, Silvia Helena Figueiredo; Scatena, Lúcia Marina; Ruffino, Antonio; Villa, Tereza Cristina Scatena

2017-01-01

In order to control tuberculosis, the Brazilian Ministry of Health recommends the decentralization of control actions directed to the Primary Health Care, and there are few studies on the performance of the Tuberculosis Control Program in decentralized contexts. To evaluate the performance of Primary Health Care services in tuberculosis treatment. This is an evaluative study with cross-sectional approach conducted in 2011. Two hundred and thirty-nine health professionals from Primary Health Care units were interviewed using a structured instrument based on the evaluation reference of the health services quality (structure - process - results). The performance of these services was analyzed applying techniques of descriptive statistics, validation, and construction of indicators and by determining the reduced variable "Z". The indicators "participation of professionals in tuberculosis patients' care" (structure) and "reference and counterreference" (process) had the best evaluations, whereas "professional training" (structure) and "external actions for tuberculosis control" (process) had the worst results. The decentralization of tuberculosis control actions has been taking place in a vertical manner in Primary Health Care. The challenge of controlling tuberculosis involves overcoming constraints related to the engagement, training, and turnover rates among health professionals, which is a coordination between services and monitoring of control actions in Primary Health Care.

On the use of an Arduino-based controller to control the charging process of a wind turbine

NASA Astrophysics Data System (ADS)

Mahmuddin, Faisal; Yusran, Ahmad Muhtam; Klara, Syerly

2017-02-01

In order to avoid an excessive charging voltage which can damage power storage when converting wind energy using a turbine, it is necessary to control the charging voltage of the turbine generator. In the present study, a charging controller which uses an Arduino microcontroller, is designed. 3 (three) indicator lights are installed to indicate the battery charging process, power diversion to dummy load and battery power level. The performance of the designed controller is evaluated by simulating 3 cases. In this simulation, a battery with maximum voltage of 12.4 V is used. Case 1 is performed with input voltage equals the one set in Arduino which is 10 V. In this case, the battery is charged up to 10.8 V. In case 2, the input voltage is 13 V while the maximum voltage set in Arduino is also 13 V. In this case, the battery is charged up to maximum voltage of the battery. Moreover, the dummy load indicator is ON and charging indicator is OFF after the maximum charging voltage is reached because the electricity is flowed to the dummy load. In the final case, the input voltage is set to be 16 V while the maximum voltage set in Arduino is 13 V. In this case, the charging indicator is OFF and dummy load indicator is ON which means that the Arduino has successfully switched the power to be flowed to dummy load. From the 3 (three) cases, it can be concluded that the designed controller works perfectly to control the charging process of the wind turbine. Moreover, the charging time needed in each case can also be determined.

34 CFR 361.89 - Enforcement procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Standards and Performance Indicators § 361.89 Enforcement procedures. (a) If a DSU fails to meet the... satisfactory level on the compliance indicators. (Approved by the Office of Management and Budget under control...

Indicators in Perspective. The Use of Quality Indicators in Vocational Education and Training. CEDEFOP Document.

ERIC Educational Resources Information Center

Van den Berghe, Wouter

Indicators are used in quite different ways in vocational education and training, from control and accountability to performance and quality purposes. A classification model has been proposed in which many indicators can fit. It is based on two important dimensions of indicators: (1) the "message" relating to the information content,…

From neuro-pigments to neural efficiency: The relationship between retinal carotenoids and behavioral and neuroelectric indices of cognitive control in childhood.

PubMed

Walk, Anne M; Khan, Naiman A; Barnett, Sasha M; Raine, Lauren B; Kramer, Arthur F; Cohen, Neal J; Moulton, Christopher J; Renzi-Hammond, Lisa M; Hammond, Billy R; Hillman, Charles H

2017-08-01

Lutein and zeaxanthin are plant pigments known to preferentially accumulate in neural tissue. Macular Pigment Optical Density (MPOD), a non-invasive measure of retinal carotenoids and surrogate measure of brain carotenoid concentration, has been associated with disease prevention and cognitive health. Superior MPOD status in later adulthood has been shown to provide neuroprotective effects on cognition. Given that childhood signifies a critical period for carotenoid accumulation in brain, it is likely that the beneficial impact would be evident during development, though this relationship has not been directly investigated. The present study investigated the relationship between MPOD and the behavioral and neuroelectric indices elicited during a cognitive control task in preadolescent children. 49 participants completed a modified flanker task while event-related potentials (ERPs) were recorded to assess the P3 component of the ERP waveform. MPOD was associated with both behavioral performance and P3 amplitude such that children with higher MPOD had more accurate performance and lower P3 amplitudes. These relationships were more pronounced for trials requiring greater amounts of cognitive control. These results indicate that children with higher MPOD may respond to cognitive tasks more efficiently, maintaining high performance while displaying neural indices indicative of lower cognitive load. These findings provide novel support for the neuroprotective influence of retinal carotenoids during preadolescence. Copyright © 2017 Elsevier B.V. All rights reserved.

42 CFR 456.433 - Initial continued stay review date.

Code of Federal Regulations, 2010 CFR

2010-10-01

... SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS UTILIZATION CONTROL Utilization Control: Intermediate Care... after admission, if indicated at the time of admission; and (d) The group performing UR insures that the...

42 CFR 456.433 - Initial continued stay review date.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS UTILIZATION CONTROL Utilization Control: Intermediate Care... after admission, if indicated at the time of admission; and (d) The group performing UR insures that the...

Alterations of motor performance and brain cortex mitochondrial function during ethanol hangover.

PubMed

Bustamante, Juanita; Karadayian, Analia G; Lores-Arnaiz, Silvia; Cutrera, Rodolfo A

2012-08-01

Ethanol has been known to affect various behavioral parameters in experimental animals, even several hours after ethanol (EtOH) is absent from blood circulation, in the period known as hangover. The aim of this study was to assess the effects of acute ethanol hangover on motor performance in association with the brain cortex energetic metabolism. Evaluation of motor performance and brain cortex mitochondrial function during alcohol hangover was performed in mice 6 hours after a high ethanol dose (hangover onset). Animals were injected i.p. either with saline (control group) or with ethanol (3.8 g/kg BW) (hangover group). Ethanol hangover group showed a bad motor performance compared with control animals (p < .05). Oxygen uptake in brain cortex mitochondria from hangover animals showed a 34% decrease in the respiratory control rate as compared with the control group. Mitochondrial complex activities were decreased being the complex I-III the less affected by the hangover condition; complex II-III was markedly decreased by ethanol hangover showing 50% less activity than controls. Complex IV was 42% decreased as compared with control animals. Hydrogen peroxide production was 51% increased in brain cortex mitochondria from the hangover group, as compared with the control animals. Quantification of the mitochondrial transmembrane potential indicated that ethanol injected animals presented 17% less ability to maintain the polarized condition as compared with controls. These results indicate that a clear decrease in proton motive force occurs in brain cortex mitochondria during hangover conditions. We can conclude that a decreased motor performance observed in the hangover group of animals could be associated with brain cortex mitochondrial dysfunction and the resulting impairment of its energetic metabolism. Copyright © 2012 Elsevier Inc. All rights reserved.

Investigating the optimal passive and active vibration controls of adjacent buildings based on performance indices using genetic algorithms

NASA Astrophysics Data System (ADS)

Hadi, Muhammad N. S.; Uz, Mehmet E.

2015-02-01

This study proposes the optimal passive and active damper parameters for achieving the best results in seismic response mitigation of coupled buildings connected to each other by dampers. The optimization to minimize the H2 and H∞ norms in the performance indices is carried out by genetic algorithms (GAs). The final passive and active damper parameters are checked for adjacent buildings connected to each other under El Centro NS 1940 and Kobe NS 1995 excitations. Using real coded GA in H∞ norm, the optimal controller gain is obtained by different combinations of the measurement as the feedback for designing the control force between the buildings. The proposed method is more effective than other metaheuristic methods and more feasible, although the control force increased. The results in the active control system show that the response of adjacent buildings is reduced in an efficient manner.

A comparison of decentralized, distributed, and centralized vibro-acoustic control.

PubMed

Frampton, Kenneth D; Baumann, Oliver N; Gardonio, Paolo

2010-11-01

Direct velocity feedback control of structures is well known to increase structural damping and thus reduce vibration. In multi-channel systems the way in which the velocity signals are used to inform the actuators ranges from decentralized control, through distributed or clustered control to fully centralized control. The objective of distributed controllers is to exploit the anticipated performance advantage of the centralized control while maintaining the scalability, ease of implementation, and robustness of decentralized control. However, and in seeming contradiction, some investigations have concluded that decentralized control performs as well as distributed and centralized control, while other results have indicated that distributed control has significant performance advantages over decentralized control. The purpose of this work is to explain this seeming contradiction in results, to explore the effectiveness of decentralized, distributed, and centralized vibro-acoustic control, and to expand the concept of distributed control to include the distribution of the optimization process and the cost function employed.

Cold startup and low temperature performance of the Brayton cycle electrical subsystem

NASA Technical Reports Server (NTRS)

Vrancik, J. E.; Bainbridge, R. C.

1971-01-01

Cold performance tests and startup tests were conducted on the Brayton-cycle inverter, motor-driven pump, dc supply, speed control with parasitic load resistor and the Brayton control system. These tests were performed with the components in a vacuum and mounted on coldplates. A temperature range of ?25 to -50 C was used for the tests. No failures occurred, and component performance gave no indication that there would be any problem with the safe operation of the Brayton power generating system.

The analysis on nonlinear control of the aircraft arresting system

NASA Astrophysics Data System (ADS)

Song, Jinchun; Du, Tianrong

2005-12-01

The aircraft arresting system is a complicated nonlinear system. This paper analyzes the mechanical-hydraulic structure of aircraft arresting system composed of electro hydraulic valve and establishes the dynamic equation of the aircraft arresting system. Based on the state-feedback linearization of nonlinear system, a PD-based controller is synthesized. Simulation studies indicate, while arresting the different type aircraft, the proposed controller has fast response, good tracking performance and strong robustness. By tuning the parameters of the PD controller, a satisfactory control performance can be guaranteed.

Reconfigurable Pointing Control for High Resolution Space Spectroscopy

NASA Technical Reports Server (NTRS)

Bayard, David S.; Kia, Tooraj; vanCleve, Jeffrey

1997-01-01

In this paper, a pointing control performance criteria is established to support high resolution space spectroscopy. Results indicate that these pointing requirements are very stringent, and would typically be difficult to meet using standard 3-axis spacecraft control. To resolve this difficulty, it is shown that performance can be significantly improved using a reconfigurable control architecture that switches among a small bank of detuned Kalman filters. The effectiveness of the control reconfiguration approach is demonstrated by example on the Space Infra, Red Telescope Facility (SIRTF) pointing system, in support of the Infrared Spectrograph (IRS) payload.

The Ability of Psychological Flexibility and Job Control to Predict Learning, Job Performance, and Mental Health

ERIC Educational Resources Information Center

Bond, Frank W.; Flaxman, Paul E.

2006-01-01

This longitudinal study tested the degree to which an individual characteristic, psychological flexibility, and a work organization variable, job control, predicted ability to learn new skills at work, job performance, and mental health, amongst call center workers in the United Kingdom (N = 448). As hypothesized, results indicated that job…

Short-Term Memory Performances during Sustained Wakefulness in Patients with Obstructive Sleep Apnea-Hypopnea Syndrome

ERIC Educational Resources Information Center

Greneche, Jerome; Krieger, Jean; Bertrand, Frederic; Erhardt, Christine; Maumy, Myriam; Tassi, Patricia

2011-01-01

Both working and immediate memories were assessed every 4 h by specific short-term memory tasks over sustained wakefulness in 12 patients with obstructive sleep apnea and hypopnea syndrome (OSAHS) and 10 healthy controls. Results indicated that OSAHS patients exhibited lower working memory performances than controls on both backward digit span and…

The Effect of Locus of Control, Self-Efficacy, and Gender-Role Identity on Academic Performance Outcomes of Female College Students

ERIC Educational Resources Information Center

Sierra, Jade Simone

2013-01-01

This quantitative study investigated the predictive worthiness of the predictor variable indices--locus of control, self-efficacy, and gender identity--to ascertain if elevated levels of the predictors influence academic performance outcomes (individually as well as interactionally). The study theorized that students with increased levels of locus…

Effects of stick dynamics on helicopter flying qualities

NASA Technical Reports Server (NTRS)

Watson, Douglas C.; Schroeder, Jeffery A.

1990-01-01

An experiment that investigated the influence of typical helicopter force-feel system dynamics on roll-axis handling qualities was conducted in concurrent ground and inflight simulations. Variations in lateral control natural frequency and damping ratio, effected by changes in inertia and damping, were evaluated in a disturbance-rejection task. Pilot ratings indicated a preference for low-inertia feel systems, although measured performance was relatively constant over the range of stick characteristics. Force-sensing was compared with position sensing as the input to the control system. Force-sensing improved performance but did not improve pilot ratings. Overall, the results indicated that control-stick dynamics, at least within a reasonable range, did not have a significant effect on pilot-vehicle performance. However, the physical effort required to maintain a desired pilot/manipulator bandwidth became objectionable as the stick inertia increased beyond 5-7 lbm, which was reflected in the pilot ratings and comments.

Satisfaction monitoring for quality control in campground management

Treesearch

Wilbur F. LaPage; Malcolm I. Bevins

1981-01-01

A 4-year study of camper satisfaction indicates that satisfaction monitoring is a useful tool for campground managers to assess their performance and achieve a high level of quality control in their service to the public. An indication of camper satisfaction with campground management is gained from a report card on which a small sample of visitors rates 14 elements of...

The effects of cognitive and behavioral control on post-stress performance

NASA Technical Reports Server (NTRS)

Foushee, H. C.; Davis, M. H.; Stephan, W. G.; Bernstein, W. M.

1980-01-01

A study was designed to investigate the effects of behavioral and cognitive control on post-stress performance. Half of the subjects exposed to loud unpredictable noise bursts were given 'behavioral' control (a button which would terminate the noise), while the other half had no behavioral control. In addition, subjects were provided with one of three levels of feedback (success, failure, or no feedback) regarding their performance during the noise. It was expected that information about performance would provide subjects with an increased sense of 'cognitive' control which would affect their appraisal of stressful events and their later performance. The results indicated that subjects given feedback performed better on subsequent tasks than those given no feedback. Perceived behavioral control had little effect on performance. The causal attributions made by subjects were used to interpret these effects. These findings were viewed as supportive of Averill's (1973) notion that various types of control are related to stress in a complex fashion. The data may also support the reformulation by Abramson et al. (1978) of learned helplessness theory.

A cluster-randomised quality improvement study to improve two inpatient stroke quality indicators.

PubMed

Williams, Linda; Daggett, Virginia; Slaven, James E; Yu, Zhangsheng; Sager, Danielle; Myers, Jennifer; Plue, Laurie; Woodward-Hagg, Heather; Damush, Teresa M

2016-04-01

Quality indicator collection and feedback improves stroke care. We sought to determine whether quality improvement training plus indicator feedback was more effective than indicator feedback alone in improving inpatient stroke indicators. We conducted a cluster-randomised quality improvement trial, randomising hospitals to quality improvement training plus indicator feedback versus indicator feedback alone to improve deep vein thrombosis (DVT) prophylaxis and dysphagia screening. Intervention sites received collaborative-based quality improvement training, external facilitation and indicator feedback. Control sites received only indicator feedback. We compared indicators pre-implementation (pre-I) to active implementation (active-I) and post-implementation (post-I) periods. We constructed mixed-effect logistic models of the two indicators with a random intercept for hospital effect, adjusting for patient, time, intervention and hospital variables. Patients at intervention sites (1147 admissions), had similar race, gender and National Institutes of Health Stroke Scale scores to control sites (1017 admissions). DVT prophylaxis improved more in intervention sites during active-I period (ratio of ORs 4.90, p<0.001), but did not differ in post-I period. Dysphagia screening improved similarly in both groups during active-I, but control sites improved more in post-I period (ratio of ORs 0.67, p=0.04). In logistic models, the intervention was independently positively associated with DVT performance during active-I period, and negatively associated with dysphagia performance post-I period. Quality improvement training was associated with early DVT improvement, but the effect was not sustained over time and was not seen with dysphagia screening. External quality improvement programmes may quickly boost performance but their effect may vary by indicator and may not sustain over time. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Force-reflection and shared compliant control in operating telemanipulators with time delay

NASA Technical Reports Server (NTRS)

Kim, Won S.; Hannaford, Blake; Bejczy, Antal K.

1992-01-01

The performance of an advanced telemanipulation system in the presence of a wide range of time delays between a master control station and a slave robot is quantified. The contemplated applications include multiple satellite links to LEO, geosynchronous operation, spacecraft local area networks, and general-purpose computer-based short-distance designs. The results of high-precision peg-in-hole tasks performed by six test operators indicate that task performance decreased linearly with introduced time delays for both kinesthetic force feedback (KFF) and shared compliant control (SCC). The rate of this decrease was substantially improved with SCC compared to KFF. Task performance at delays above 1 s was not possible using KFF. SCC enabled task performance for such delays, which are realistic values for ground-controlled remote manipulation of telerobots in space.

An approach to quality and performance control in a computer-assisted clinical chemistry laboratory.

PubMed Central

Undrill, P E; Frazer, S C

1979-01-01

A locally developed, computer-based clinical chemistry laboratory system has been in operation since 1970. This utilises a Digital Equipment Co Ltd PDP 12 and an interconnected PDP 8/F computer. Details are presented of the performance and quality control techniques incorporated into the system. Laboratory performance is assessed through analysis of results from fixed-level control sera as well as from cumulative sum methods. At a simple level the presentation may be considered purely indicative, while at a more sophisticated level statistical concepts have been introduced to aid the laboratory controller in decision-making processes. PMID:438340

Compatibility and consistency in display-control systems - Implications for aircraft decision aid design

NASA Technical Reports Server (NTRS)

Andre, Anthony D.; Wickens, Christopher D.

1992-01-01

In this study we contrast display-control movement relations defined in terms of stimulus-response (physical) compatibility with those defined by stimulus-cognitive compatibility, and we relate these findings to the issue of command versus status levels of decision aid support. A second issue addressed is the cost of inconsistency across multiple display-control mappings. Subjects performed a flight control task while responding to one to four analog indicators, formatted as either command or status displays. The results suggest that there is an advantage for the status format when subjects are required to verbally report the state of the indicator(s), but no advantage was found for either format when subjects were required to manually correct the indicated state. The data point to the importance of display-control consistency and suggest that it may even outweigh that of compatibility.

The Validity of Higher-Order Questions as a Process Indicator of Educational Quality

ERIC Educational Resources Information Center

Renaud, Robert D.; Murray, Harry G.

2007-01-01

One way to assess the quality of education in post-secondary institutions is through the use of performance indicators. Studies that have compared currently popular process indicators (e.g., library size, percentage of faculty with PhD) found that after controlling for incoming student ability, these process indicators tend to be weakly associated…

Performance on the Wechsler Adult Intelligence Scale-III in Japanese patients with schizophrenia.

PubMed

Fujino, Haruo; Sumiyoshi, Chika; Sumiyoshi, Tomiki; Yasuda, Yuka; Yamamori, Hidenaga; Ohi, Kazutaka; Fujimoto, Michiko; Umeda-Yano, Satomi; Higuchi, Arisa; Hibi, Yumiko; Matsuura, Yukako; Hashimoto, Ryota; Takeda, Masatoshi; Imura, Osamu

2014-07-01

Patients with schizophrenia have been reported to perform worse than non-schizophrenic populations on neuropsychological tests, which may be affected by cultural factors. The aim of this study was to examine the performance of a sizable number of patients with schizophrenia on the Japanese version of the Wechsler Adult Intelligence Scale-III (WAIS-III) compared with healthy controls. Performance on the WAIS-III was evaluated in 157 Japanese patients with schizophrenia and in 264 healthy control subjects. All IQ scores and four indices from the WAIS-III were impaired for patients with schizophrenia compared with healthy controls. Processing Speed was markedly disturbed, approximately 2 SD below that of the healthy control group. Among the 13 subtests, Comprehension (z = -1.70, d = 1.55), Digit Symbol Coding (z = -1.84, d = 1.88), and Symbol Search (z = -1.85, d = 1.77) were profoundly impaired relative to the healthy controls. These results indicate that the pattern and degree of impairment, as evaluated by the WAIS-III, in Japanese patients are similar to those previously reported in English-speaking patients and that the deficits of some neuropsychological domains relevant to functional outcomes are universally characteristic of schizophrenia. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

Gender Differences in Sustained Attentional Control Relate to Gender Inequality across Countries

PubMed Central

Riley, Elizabeth; Okabe, Hidefusa; Germine, Laura; Wilmer, Jeremy; Esterman, Michael; DeGutis, Joseph

2016-01-01

Sustained attentional control is critical for everyday tasks and success in school and employment. Understanding gender differences in sustained attentional control, and their potential sources, is an important goal of psychology and neuroscience and of great relevance to society. We used a large web-based sample (n = 21,484, from testmybrain.org) to examine gender differences in sustained attentional control. Our sample included participants from 41 countries, allowing us to examine how gender differences in each country relate to national indices of gender equality. We found significant gender differences in certain aspects of sustained attentional control. Using indices of gender equality, we found that overall sustained attentional control performance was lower in countries with less equality and that there were greater gender differences in performance in countries with less equality. These findings suggest that creating sociocultural conditions which value women and men equally can improve a component of sustained attention and reduce gender disparities in cognition. PMID:27802294

Gender Differences in Sustained Attentional Control Relate to Gender Inequality across Countries.

PubMed

Riley, Elizabeth; Okabe, Hidefusa; Germine, Laura; Wilmer, Jeremy; Esterman, Michael; DeGutis, Joseph

2016-01-01

Sustained attentional control is critical for everyday tasks and success in school and employment. Understanding gender differences in sustained attentional control, and their potential sources, is an important goal of psychology and neuroscience and of great relevance to society. We used a large web-based sample (n = 21,484, from testmybrain.org) to examine gender differences in sustained attentional control. Our sample included participants from 41 countries, allowing us to examine how gender differences in each country relate to national indices of gender equality. We found significant gender differences in certain aspects of sustained attentional control. Using indices of gender equality, we found that overall sustained attentional control performance was lower in countries with less equality and that there were greater gender differences in performance in countries with less equality. These findings suggest that creating sociocultural conditions which value women and men equally can improve a component of sustained attention and reduce gender disparities in cognition.

Objective assessment of operator performance during ultrasound-guided procedures.

PubMed

Tabriz, David M; Street, Mandie; Pilgram, Thomas K; Duncan, James R

2011-09-01

Simulation permits objective assessment of operator performance in a controlled and safe environment. Image-guided procedures often require accurate needle placement, and we designed a system to monitor how ultrasound guidance is used to monitor needle advancement toward a target. The results were correlated with other estimates of operator skill. The simulator consisted of a tissue phantom, ultrasound unit, and electromagnetic tracking system. Operators were asked to guide a needle toward a visible point target. Performance was video-recorded and synchronized with the electromagnetic tracking data. A series of algorithms based on motor control theory and human information processing were used to convert raw tracking data into different performance indices. Scoring algorithms converted the tracking data into efficiency, quality, task difficulty, and targeting scores that were aggregated to create performance indices. After initial feasibility testing, a standardized assessment was developed. Operators (N = 12) with a broad spectrum of skill and experience were enrolled and tested. Overall scores were based on performance during ten simulated procedures. Prior clinical experience was used to independently estimate operator skill. When summed, the performance indices correlated well with estimated skill. Operators with minimal or no prior experience scored markedly lower than experienced operators. The overall score tended to increase according to operator's clinical experience. Operator experience was linked to decreased variation in multiple aspects of performance. The aggregated results of multiple trials provided the best correlation between estimated skill and performance. A metric for the operator's ability to maintain the needle aimed at the target discriminated between operators with different levels of experience. This study used a highly focused task model, standardized assessment, and objective data analysis to assess performance during simulated ultrasound-guided needle placement. The performance indices were closely related to operator experience.

Variability in reaction time performance of younger and older adults.

PubMed

Hultsch, David F; MacDonald, Stuart W S; Dixon, Roger A

2002-03-01

Age differences in three basic types of variability were examined: variability between persons (diversity), variability within persons across tasks (dispersion), and variability within persons across time (inconsistency). Measures of variability were based on latency performance from four measures of reaction time (RT) performed by a total of 99 younger adults (ages 17--36 years) and 763 older adults (ages 54--94 years). Results indicated that all three types of variability were greater in older compared with younger participants even when group differences in speed were statistically controlled. Quantile-quantile plots showed age and task differences in the shape of the inconsistency distributions. Measures of within-person variability (dispersion and inconsistency) were positively correlated. Individual differences in RT inconsistency correlated negatively with level of performance on measures of perceptual speed, working memory, episodic memory, and crystallized abilities. Partial set correlation analyses indicated that inconsistency predicted cognitive performance independent of level of performance. The results indicate that variability of performance is an important indicator of cognitive functioning and aging.

Voltage directive drive with claw pole motor and control without rotor position indicator

NASA Astrophysics Data System (ADS)

Stroenisch, Volker Ewald

Design and testing of a voltage directive drive for synchronous variable speed claw pole motor and control without rotor position indicator is described. Economic analysis of the designed regulation is performed. Computations of stationary and dynamic behavior are given and experimental operational behavior is determined. The motors can be used for electric transportation vehicles, diesel motors, and electric railway engines.

Sense of agency in continuous action: Assistance-induced performance improvement is self-attributed even with knowledge of assistance.

PubMed

Inoue, Kazuya; Takeda, Yuji; Kimura, Motohiro

2017-02-01

In a task involving continuous action to achieve a goal, the sense of agency increases with an improvement in task performance that is induced by unnoticed computer assistance. This study investigated how explicit instruction about the existence of computer assistance affects the increase of sense of agency that accompanies performance improvement. Participants performed a continuous action task in which they controlled the direction of motion of a dot to a goal by pressing keys. When instructions indicated the absence of assistance, the sense of agency increased with performance improvement induced by computer assistance, replicating previous findings. Interestingly, this increase of sense of agency was also observed even when instructions indicated the presence of assistance. These results suggest that even when a plausible cause of performance improvement other than one's own action exists, the improvement can be misattributed to one's own control of action, resulting in an increased sense of agency. Copyright © 2016 Elsevier Inc. All rights reserved.

Women's and Men's Marriages: Marital Satisfaction, Perceived Control, and Attitudes toward Women.

ERIC Educational Resources Information Center

Madden, Margaret E.

Previous research on marriage indicates that perceptions of control are important to marital satisfaction. To investigate the relationship between attributions of personal control and other variables in marriage, e.g., measures of satisfaction, decision making, and task performance, and attributions of control over decisions and tasks, and to…

Effect of Performance Feedback on Community Health Workers’ Motivation and Performance in Madhya Pradesh, India: A Randomized Controlled Trial

PubMed Central

Matheke-Fischer, Michael; Lesh, Neal

2016-01-01

Background Small-scale community health worker (CHW) programs provide basic health services and strengthen health systems in resource-poor settings. This paper focuses on improving CHW performance by providing individual feedback to CHWs working with an mHealth program to address malnutrition in children younger than 5 years. Objective The paper aims to evaluate the immediate and retention effects of providing performance feedback and supportive supervision on CHW motivation and performance for CHWs working with an mHealth platform to reduce malnutrition in five districts of Madhya Pradesh, India. We expected a positive impact on CHW performance for the indicator they received feedback on. Performance on indicators the CHW did not receive feedback on was not expected to change. Methods In a randomized controlled trial, 60 CHWs were randomized into three treatment groups based on overall baseline performance ranks to achieve balanced treatment groups. Data for each treatment indicator were analyzed with the other two treatments acting as the control. In total, 10 CHWs were lost to follow-up. There were three performance indicators: case activity, form submissions, and duration of counseling. Each group received weekly calls to provide performance targets and discuss their performance on the specific indicator they were allocated to as well as any challenges or technical issues faced during the week for a 6-week period. Data were collected for a further 4 weeks to assess intertemporal sustained effects of the intervention. Results We found positive and significant impacts on duration of counseling, whereas case activity and number of form submissions did not show significant improvements as a result of the intervention. We found a moderate to large effect (Glass’s delta=0.97, P=.004) of providing performance feedback on counseling times in the initial 6 weeks. These effects were sustained in the postintervention period (Glass’s delta=1.69, P<.001). The counseling times decreased slightly from the intervention to postintervention period by 2.14 minutes (P=.01). Case activity improved for all CHWs after the intervention. We also performed the analysis by replacing the CHWs lost to follow-up with those in their treatment groups with the closest ranks in baseline performance and found similar results. Conclusions Calls providing performance feedback are effective in improving CHW motivation and performance. Providing feedback had a positive effect on performance in the case of duration of counseling. The results suggest that difficulty in achieving the performance target can affect results of performance feedback. Regardless of the performance information disclosed, calls can improve performance due to elements of supportive supervision included in the calls encouraging CHW motivation. PMID:27927607

Optimum aerobic volume control based on continuous in-line oxygen uptake monitoring.

PubMed

Svardal, K; Lindtner, S; Winkler, S

2003-01-01

Dynamic adaptation of the aerated volume to changing load conditions is essential to maximise the nitrogen removal performance and to minimise energy consumption. A control strategy is presented which provides optimum aerobic volume control (OAV-control concept) based on continuous in-line oxygen uptake monitoring. For ammonium concentrations below 1 mg/l the oxygen uptake rate shows a strong and almost linear dependency on the ammonium concentration. Therefore, the oxygen uptake rate is an ideal indicator for the nitrification performance in activated sludge systems. The OAV-control concept provides dynamic variation of the minimum aerobic volume required for complete nitrification and therefore maximises the denitrification performance. In-line oxygen uptake monitoring is carried out by controlling the oxygen concentration in a continuous aerated zone of the aeration tank and measuring the total air flow to the aeration tank. The total air flow to the aeration tank is directly proportional to the current oxygen uptake rate and can therefore be used as an indicator for the required aerobic volume. The instrumentation requirements for installation of the OAV-control are relatively low, oxygen sensors in the aeration tank and an on-line air flow measurement are needed. This enables individual control of aeration tanks operated in parallel at low investment costs. The OAV-control concept is installed at the WWTP Linz-Asten (1 Mio PE) and shows very good results. Full scale results are presented.

Dissociable influences of reward motivation and positive emotion on cognitive control.

PubMed

Chiew, Kimberly S; Braver, Todd S

2014-06-01

It is becoming increasingly appreciated that affective and/or motivational influences contribute strongly to goal-oriented cognition and behavior. An unresolved question is whether emotional manipulations (i.e., direct induction of affectively valenced subjective experience) and motivational manipulations (e.g., delivery of performance-contingent rewards and punishments) have similar or distinct effects on cognitive control. Prior work has suggested that reward motivation can reliably enhance a proactive mode of cognitive control, whereas other evidence is suggestive that positive emotion improves cognitive flexibility, but reduces proactive control. However, a limitation of the prior research is that reward motivation and positive emotion have largely been studied independently. Here, we directly compared the effects of positive emotion and reward motivation on cognitive control with a tightly matched, within-subjects design, using the AX-continuous performance task paradigm, which allows for relative measurement of proactive versus reactive cognitive control. High-resolution pupillometry was employed as a secondary measure of cognitive dynamics during task performance. Robust increases in behavioral and pupillometric indices of proactive control were observed with reward motivation. The effects of positive emotion were much weaker, but if anything, also reflected enhancement of proactive control, a pattern that diverges from some prior findings. These results indicate that reward motivation has robust influences on cognitive control, while also highlighting the complexity and heterogeneity of positive-emotion effects. The findings are discussed in terms of potential neurobiological mechanisms.

Attentional Control and Subjective Executive Function in Treatment-Naive Adults with Attention Deficit Hyperactivity Disorder

PubMed Central

Grane, Venke Arntsberg; Endestad, Tor; Pinto, Arnfrid Farbu; Solbakk, Anne-Kristin

2014-01-01

We investigated performance-derived measures of executive control, and their relationship with self- and informant reported executive functions in everyday life, in treatment-naive adults with newly diagnosed Attention Deficit Hyperactivity Disorder (ADHD; n = 36) and in healthy controls (n = 35). Sustained attentional control and response inhibition were examined with the Test of Variables of Attention (T.O.V.A.). Delayed responses, increased reaction time variability, and higher omission error rate to Go signals in ADHD patients relative to controls indicated fluctuating levels of attention in the patients. Furthermore, an increment in NoGo commission errors when Go stimuli increased relative to NoGo stimuli suggests reduced inhibition of task-irrelevant stimuli in conditions demanding frequent responding. The ADHD group reported significantly more cognitive and behavioral executive problems than the control group on the Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A). There were overall not strong associations between task performance and ratings of everyday executive function. However, for the ADHD group, T.O.V.A. omission errors predicted self-reported difficulties on the Organization of Materials scale, and commission errors predicted informant reported difficulties on the same scale. Although ADHD patients endorsed more symptoms of depression and anxiety on the Achenbach System of Empirically Based Assessment (ASEBA) than controls, ASEBA scores were not significantly associated with T.O.V.A. performance scores. Altogether, the results indicate multifaceted alteration of attentional control in adult ADHD, and accompanying subjective difficulties with several aspects of executive function in everyday living. The relationships between the two sets of data were modest, indicating that the measures represent non-redundant features of adult ADHD. PMID:25545156

Attentional control and subjective executive function in treatment-naive adults with Attention Deficit Hyperactivity Disorder.

PubMed

Grane, Venke Arntsberg; Endestad, Tor; Pinto, Arnfrid Farbu; Solbakk, Anne-Kristin

2014-01-01

We investigated performance-derived measures of executive control, and their relationship with self- and informant reported executive functions in everyday life, in treatment-naive adults with newly diagnosed Attention Deficit Hyperactivity Disorder (ADHD; n = 36) and in healthy controls (n = 35). Sustained attentional control and response inhibition were examined with the Test of Variables of Attention (T.O.V.A.). Delayed responses, increased reaction time variability, and higher omission error rate to Go signals in ADHD patients relative to controls indicated fluctuating levels of attention in the patients. Furthermore, an increment in NoGo commission errors when Go stimuli increased relative to NoGo stimuli suggests reduced inhibition of task-irrelevant stimuli in conditions demanding frequent responding. The ADHD group reported significantly more cognitive and behavioral executive problems than the control group on the Behavior Rating Inventory of Executive Function-Adult Version (BRIEF-A). There were overall not strong associations between task performance and ratings of everyday executive function. However, for the ADHD group, T.O.V.A. omission errors predicted self-reported difficulties on the Organization of Materials scale, and commission errors predicted informant reported difficulties on the same scale. Although ADHD patients endorsed more symptoms of depression and anxiety on the Achenbach System of Empirically Based Assessment (ASEBA) than controls, ASEBA scores were not significantly associated with T.O.V.A. performance scores. Altogether, the results indicate multifaceted alteration of attentional control in adult ADHD, and accompanying subjective difficulties with several aspects of executive function in everyday living. The relationships between the two sets of data were modest, indicating that the measures represent non-redundant features of adult ADHD.

Spiral drawing performance as an indicator of fine motor function in people with multiple sclerosis.

PubMed

Longstaff, M G; Heath, R A

2006-10-01

This study investigated spiral drawing performance as an indicator of fine motor function, as well as to gain insight into adaptive movement strategies used by people with multiple sclerosis (MS). Seven people with MS, nine younger controls (mean age of 20) and eight older controls (mean age of 40) drew spirals on a graphics tablet at a comfortable speed and size. Spirography (i.e., a subjective visual assessment of the static trace) revealed indications of reduced control of the pen for people with MS. Analysis of the movements showed that people with MS tended to draw the spirals slower and with less pen pressure than controls. All groups increased their speed and pressure along with spiral size, but this increase was much steeper for the controls. MS participants drew spirals with more variability around an ideal trajectory, highlighting fine motor control degradation. MS patients tended to use a smaller scaling ratio, resulting in smaller spirals for a given number of revolutions. The younger and older control groups drew the spirals in a similar manner, and age was not a significant factor in any of the analyses. It is argued that the relatively lower pressure used, and slower, smaller movements (particularly during the more difficult outer sections of the spiral) are in part an adaptive strategy used to reduce movement variability. These results demonstrate the utility of the analysis of spiral movements as an objective technique for assessing motor control degradation, which can compliment the subjective rating based on the static pen trace. As such, it can provide further insight into the biomechanical strategies used when performing fine movements.

Adaptive dynamic programming for finite-horizon optimal control of discrete-time nonlinear systems with ε-error bound.

PubMed

Wang, Fei-Yue; Jin, Ning; Liu, Derong; Wei, Qinglai

2011-01-01

In this paper, we study the finite-horizon optimal control problem for discrete-time nonlinear systems using the adaptive dynamic programming (ADP) approach. The idea is to use an iterative ADP algorithm to obtain the optimal control law which makes the performance index function close to the greatest lower bound of all performance indices within an ε-error bound. The optimal number of control steps can also be obtained by the proposed ADP algorithms. A convergence analysis of the proposed ADP algorithms in terms of performance index function and control policy is made. In order to facilitate the implementation of the iterative ADP algorithms, neural networks are used for approximating the performance index function, computing the optimal control policy, and modeling the nonlinear system. Finally, two simulation examples are employed to illustrate the applicability of the proposed method.

Neural correlates of impaired cognitive control over working memory in schizophrenia.

PubMed

Eich, Teal S; Nee, Derek Evan; Insel, Catherine; Malapani, Chara; Smith, Edward E

2014-07-15

One of the most common deficits in patients with schizophrenia (SZ) is in working memory (WM), which has wide-reaching impacts across cognition. However, previous approaches to studying WM in SZ have used tasks that require multiple cognitive-control processes, making it difficult to determine which specific cognitive and neural processes underlie the WM impairment. We used functional magnetic resonance imaging to investigate component processes of WM in SZ. Eighteen healthy controls (HCs) and 18 patients with SZ performed an item-recognition task that permitted separate neural assessments of 1) WM maintenance, 2) inhibition, and 3) interference control in response to recognition probes. Before inhibitory demands, posterior ventrolateral prefrontal cortex (VLPFC), an area involved in WM maintenance, was activated to a similar degree in both HCs and patients, indicating preserved maintenance operations in SZ. When cued to inhibit items from WM, HCs showed reduced activation in posterior VLPFC, commensurate with appropriately inhibiting items from WM. However, these inhibition-related reductions were absent in patients. When later probed with items that should have been inhibited, patients showed reduced behavioral performance and increased activation in mid-VLPFC, an area implicated in interference control. A mediation analysis indicated that impaired inhibition led to increased reliance on interference control and reduced behavioral performance. In SZ, impaired control over memory, manifested through proactive inhibitory deficits, leads to increased reliance on reactive interference-control processes. The strain on interference-control processes results in reduced behavioral performance. Thus, inhibitory deficits in SZ may underlie widespread impairments in WM and cognition. © 2013 Society of Biological Psychiatry Published by Society of Biological Psychiatry All rights reserved.

Adaptive Working Memory Training Reduces the Negative Impact of Anxiety on Competitive Motor Performance.

PubMed

Ducrocq, Emmanuel; Wilson, Mark; Smith, Tim J; Derakshan, Nazanin

2017-12-01

Optimum levels of attentional control are essential to prevent athletes from experiencing performance breakdowns under pressure. The current study explored whether training attentional control using the adaptive dual n-back paradigm, designed to directly target processing efficiency of the main executive functions of working memory (WM), would result in transferrable effects on sports performance outcomes. A total of 30 tennis players were allocated to an adaptive WM training or active control group and underwent 10 days of training. Measures of WM capacity as well as performance and objective gaze indices of attentional control in a tennis volley task were assessed in low- and high-pressure posttraining conditions. Results revealed significant benefits of training on WM capacity, quiet eye offset, and tennis performance in the high-pressure condition. Our results confirm and extend previous findings supporting the transfer of cognitive training benefits to objective measures of sports performance under pressure.

Physiological and Functional Alterations after Spaceflight and Bed Rest.

PubMed

Mulavara, Ajitkumar P; Peters, Brian T; Miller, Chris A; Kofman, Igor S; Reschke, Millard F; Taylor, Laura C; Lawrence, Emily L; Wood, Scott J; Laurie, Steven S; Lee, Stuart M C; Buxton, Roxanne E; May-Phillips, Tiffany R; Stenger, Michael B; Ploutz-Snyder, Lori L; Ryder, Jeffrey W; Feiveson, Alan H; Bloomberg, Jacob J

2018-04-03

Exposure to microgravity causes alterations in multiple physiological systems, potentially impacting the ability of astronauts to perform critical mission tasks. The goal of this study was to determine the effects of spaceflight on functional task performance and to identify the key physiological factors contributing to their deficits. A test battery comprised of 7 functional tests and 15 physiological measures was used to investigate the sensorimotor, cardiovascular and neuromuscular adaptations to spaceflight. Astronauts were tested before and after 6-month spaceflights. Subjects were also tested before and after 70 days of 6° head-down bed rest, a spaceflight analog, to examine the role of axial body unloading on the spaceflight results. These subjects included Control and Exercise groups to examine the effects of exercise during bed rest. Spaceflight subjects showed the greatest decrement in performance during functional tasks that required the greatest demand for dynamic control of postural equilibrium which was paralleled by similar decrements in sensorimotor tests that assessed postural and dynamic gait control. Other changes included reduced lower limb muscle performance and increased heart rate to maintain blood pressure. Exercise performed during bed rest prevented detrimental change in neuromuscular and cardiovascular function, however, both bed rest groups experienced functional and balance deficits similar to spaceflight subjects. Bed rest data indicates that body support unloading experienced during spaceflight contributes to postflight postural control dysfunction. Further, the bed rest results in the Exercise group of subjects confirm that resistance and aerobic exercises performed during spaceflight can play an integral role in maintaining neuromuscular and cardiovascular function, which can help in reducing decrements in functional performance. These results indicate that a countermeasure to mitigate postflight postural control dysfunction is required to maintain functional performance.

Why are Chinese Mothers More Controlling than American Mothers? “My Child is My Report Card”

PubMed Central

Ng, Florrie Fei-Yin; Pomerantz, Eva M.; Deng, Ciping

2013-01-01

Chinese parents exert more control over children than do American parents. The current research examined whether this is due in part to Chinese parents' feelings of worth being more contingent on children's performance. Twice over a year, 215 mothers and children (mean age = 12.86 years) in China and the United States (European and African Americans) reported on psychologically controlling parenting. Mothers also indicated the extent to which their worth is contingent on children's performance. Psychologically controlling parenting was higher among Chinese than American mothers, particularly European (vs. African) American mothers. Chinese (vs. American) mothers' feelings of worth were more contingent on children's performance, with this contributing to their heightened psychological control relative to American mothers. PMID:23581633

The incorporation of activities to control dengue by community health agents

PubMed Central

Cazola, Luiza Helena de Oliveira; Tamaki, Edson Mamoru; Pontes, Elenir Rose Jardim Cury; de Andrade, Sonia Maria Oliveira

2014-01-01

OBJECTIVE To evaluate the performance of Community Health Agents when dengue control activities were added to their tasks. METHODS Performance was measured comparing the evolution of selected indicators from the Brazilian National Dengue Control Program and the Family Health Strategy for 2002 to 2008 in the municipality of Sao Gabriel do Oeste, MS, Central Western Brazil, with those of Rio Verde de Mato Grosso, neighboring municipality with demographic, socioeconomic and health services similarities. Data were collected from municipal databases of the Information System for Yellow Fever and Dengue and the Information System for Primary Healthcare of the Mato Grosso do Sul State Health Office. The variables selected for the family health strategy activities were: monthly home visits, pregnant women whose antenatal care began in the first trimester, children under one with up-to-date vaccinations and hypertensive patients. Those selected for the Brazilian National Dengue Control Program were: properties inspected with Aedes aegypti and properties not inspected. RESULTS The two municipalities maintained a similar trend in dengue control indicators in the period studied. With regard to the Family Health Strategy, in 2002 Sao Gabriel do Oeste was better off in three of the four indicators studied, however, this situation was reversed at the end of the period when the county was overtaken by Rio Verde de Mato Grosso in three of the four indicators analyzed, including, the monthly average community health worker visits per registered family, the main activity of a Family Health Strategy agent. CONCLUSIONS: Incorporating the National Dengue Control Program into the Family Health Strategy is viable and developed without prejudice to dengue control activities, however, the same did not occur with the activities of family health in Sao Gabriel do Oeste. The additional workload of the community health workers is the most likely hypothesis for the declining performance of these agents in the Family Health Strategy activities. PMID:24789644

NCC simulation model. Phase 2: Simulating the operations of the Network Control Center and NCC message manual

NASA Technical Reports Server (NTRS)

Benjamin, Norman M.; Gill, Tepper; Charles, Mary

1994-01-01

The network control center (NCC) provides scheduling, monitoring, and control of services to the NASA space network. The space network provides tracking and data acquisition services to many low-earth orbiting spacecraft. This report describes the second phase in the development of simulation models for the FCC. Phase one concentrated on the computer systems and interconnecting network.Phase two focuses on the implementation of the network message dialogs and the resources controlled by the NCC. Performance measures were developed along with selected indicators of the NCC's operational effectiveness.The NCC performance indicators were defined in terms of the following: (1) transfer rate, (2) network delay, (3) channel establishment time, (4) line turn around time, (5) availability, (6) reliability, (7) accuracy, (8) maintainability, and (9) security. An NCC internal and external message manual is appended to this report.

Robust tuning of robot control systems

NASA Technical Reports Server (NTRS)

Minis, I.; Uebel, M.

1992-01-01

The computed torque control problem is examined for a robot arm with flexible, geared, joint drive systems which are typical in many industrial robots. The standard computed torque algorithm is not directly applicable to this class of manipulators because of the dynamics introduced by the joint drive system. The proposed approach to computed torque control combines a computed torque algorithm with torque controller at each joint. Three such control schemes are proposed. The first scheme uses the joint torque control system currently implemented on the robot arm and a novel form of the computed torque algorithm. The other two use the standard computed torque algorithm and a novel model following torque control system based on model following techniques. Standard tasks and performance indices are used to evaluate the performance of the controllers. Both numerical simulations and experiments are used in evaluation. The study shows that all three proposed systems lead to improved tracking performance over a conventional PD controller.

[Methodology for the comprehensive evaluation of the quality of performance of activities of medical and social experts].

PubMed

Moskalenko, V F; Gorban', Ie M; Marunich, V V; Ipatov, A V; Sergiieni, O V

2001-01-01

The paper scientifically substantiates methodology, approaches, criteria, and control indices for assessment of activities of establishments of medical-and-social performance. Most indices for efficiency and certain indices for week points in the work of establishments of the service depend on interaction thereof with curative- and prophylactic institutions; the best results with the problem of prevention of disability and rehabilitation of invalids are supposed to be achieved through collaborative efforts. Other criteria and intermediate indices having an effect on the quality of activities reflect the resource- and trained personnel supplies of establishments of the service, amount of work, organizational measures designed to raise the quality of medical-and-social expert performance.

Application of capability indices and control charts in the analytical method control strategy.

PubMed

Oliva, Alexis; Llabres Martinez, Matías

2017-08-01

In this study, we assessed the usefulness of control charts in combination with the process capability indices, C pm and C pk , in the control strategy of an analytical method. The traditional X-chart and moving range chart were used to monitor the analytical method over a 2-year period. The results confirmed that the analytical method is in-control and stable. Different criteria were used to establish the specifications limits (i.e. analyst requirements) for fixed method performance (i.e. method requirements). If the specification limits and control limits are equal in breadth, the method can be considered "capable" (C pm  = 1), but it does not satisfy the minimum method capability requirements proposed by Pearn and Shu (2003). Similar results were obtained using the C pk index. The method capability was also assessed as a function of method performance for fixed analyst requirements. The results indicate that the method does not meet the requirements of the analytical target approach. A real-example data of a SEC with light-scattering detection method was used as a model whereas previously published data were used to illustrate the applicability of the proposed approach. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Role of beliefs and emotions in numerical problem solving in university physics education

NASA Astrophysics Data System (ADS)

Bodin, Madelen; Winberg, Mikael

2012-06-01

Numerical problem solving in classical mechanics in university physics education offers a learning situation where students have many possibilities of control and creativity. In this study, expertlike beliefs about physics and learning physics together with prior knowledge were the most important predictors of the quality of performance of a task with many degrees of freedom. Feelings corresponding to control and concentration, i.e., emotions that are expected to trigger students’ intrinsic motivation, were also important in predicting performance. Unexpectedly, intrinsic motivation, as indicated by enjoyment and interest, together with students’ personal interest and utility value beliefs did not predict performance. This indicates that although a certain degree of enjoyment is probably necessary, motivated behavior is rather regulated by integration and identification of expertlike beliefs about learning and are more strongly associated with concentration and control during learning and, ultimately, with high performance. The results suggest that the development of students’ epistemological beliefs is important for students’ ability to learn from realistic problem-solving situations with many degrees of freedom in physics education.

Clinical Characteristics of Impaired Trunk Control in Children with Spastic Cerebral Palsy

ERIC Educational Resources Information Center

Heyrman, Lieve; Desloovere, Kaat; Molenaers, Guy; Verheyden, Geert; Klingels, Katrijn; Monbaliu, Elegast; Feys, Hilde

2013-01-01

This study aimed to identify clinical characteristics of impaired trunk control in hundred children with spastic CP (mean age 11.4 [plus or minus] 2.1 years, range 8-15 years). Assessment of trunk control was performed with the Trunk Control Measurement Scale (TCMS). Trunk control was clearly impaired, indicated by a median total TCMS score of…

A novel integrated approach for path following and directional stability control of road vehicles after a tire blow-out

NASA Astrophysics Data System (ADS)

Wang, Fei; Chen, Hong; Guo, Konghui; Cao, Dongpu

2017-09-01

The path following and directional stability are two crucial problems when a road vehicle experiences a tire blow-out or sudden tire failure. Considering the requirement of rapid road vehicle motion control during a tire blow-out, this article proposes a novel linearized decoupling control procedure with three design steps for a class of second order multi-input-multi-output non-affine system. The evaluating indicators for controller performance are presented and a performance related control parameter distribution map is obtained based on the stochastic algorithm which is an innovation for non-blind parameter adjustment in engineering implementation. The analysis on the robustness of the proposed integrated controller is also performed. The simulation studies for a range of driving conditions are conducted, to demonstrate the effectiveness of the proposed controller.

Diagnostic Efficiency of "DSM-IV" Indicators for Binge Eating Episodes

ERIC Educational Resources Information Center

White, Marney A.; Grilo, Carlos M.

2011-01-01

Ceach indicator criterion in separate analyses comparing BED, BN, and combined BED + BN groups relative to controls. Results: PPPs and NPPs suggest all of the indicators have predictive value, with "eating alone because embarrassed" (PPP = 0.80) "and feeling disgusted" (NPP = 0.93) performing as the best inclusion and exclusion criteria,…

New Control Design Principles Based on Measured Performance and Energy Analysis of HVAC (Heating, Ventilating, and Air-Conditioning) Systems.

DTIC Science & Technology

1985-01-01

components must also perform accurately if control is to be accurate, tests were made to determine if these components were likely to introduce more...efficient. However, it also greatly increases the com- plexity of the control systems, since room temperature measurements must be made for each zone, with...involving a psychrometer (a dry-bulb and a wet-bulb mercury thermometer) provides only a rough indication. Calibration is time- consuming and only partly

Output feedback regulator design for jet engine control systems

NASA Technical Reports Server (NTRS)

Merrill, W. C.

1977-01-01

A multivariable control design procedure based on the output feedback regulator formulation is described and applied to turbofan engine model. Full order model dynamics, were incorporated in the example design. The effect of actuator dynamics on closed loop performance was investigaged. Also, the importance of turbine inlet temperature as an element of the dynamic feedback was studied. Step responses were given to indicate the improvement in system performance with this control. Calculation times for all experiments are given in CPU seconds for comparison purposes.

Heart rate variability during motor and cognitive tasks in females with major depressive disorder

PubMed Central

Nugent, Allison Carol; Bain, Earle Eugene; Thayer, Julian Francis; Sollers, John James; Drevets, Wayne Curtis

2010-01-01

Research indicates that major depressive disorder (MDD) is associated with alterations in autonomic control, particularly cardiac control as measured by heart rate variability (HRV). In this preliminary study, we investigated the neural correlates of autonomic control by measuring both HRV and associated brain activity during the performance of mildly stressful tasks. Medically healthy female subjects with MDD (N=10) and healthy controls (N=7) underwent H2 15O-PET and ECG recording while performing a handgrip motor task and an n-back task. Indices of HRV were calculated and correlated with regional cerebral blood flow (rCBF). Differences in the rCBF and HRV correlations between depressed and healthy subjects were evident in both the medial and lateral orbital cortices. In addition, these areas appeared to be involved in different facets of autonomic control with regard to sympathetic or parasympathetic dominance of cardiac control. These results are consistent with the known roles of networks within the orbital cortex in both autonomic control and the pathophysiology of MDD. PMID:21129936

Age-related changes in executive control and their relationships with activity performance in handwriting.

PubMed

Rosenblum, Sara; Engel-Yeger, Batya; Fogel, Yael

2013-04-01

Deterioration in the frontal and prefrontal cortex associated with executive functions (EF) occurs with age and may be associated with changes in daily performance. The aim of the present study was to describe changes occurring with age in Executive Functions (EF) and handwriting activity, as well as to analyze relationships between age, EF and handwriting performance. The study population included 80 healthy participants (aged 31 to 76+) living in the community. After answering five questions about their writing habits, the participants completed the Behavioral Assessment of the Dysexecutive Syndrome (BADS). In addition, they performed a handwriting task on a digitizer included in the Computerized Penmanship Evaluation Tool (ComPET), which provides kinematic measures of the handwriting process. Significant differences were found between the four age groups for both EF and temporal and spatial handwriting measures. A series of regressions indicated that age predicted 35% of the variance of the BADS profile score (EF control) and 32% of the variance of in-air time while writing. The results of this study indicated age effect on both EF control and handwriting performance. Possible implications for further research and clinical evaluation and intervention are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Multimodal Pilot Behavior in Multi-Axis Tracking Tasks with Time-Varying Motion Cueing Gains

NASA Technical Reports Server (NTRS)

Zaal, P. M. T; Pool, D. M.

2014-01-01

In a large number of motion-base simulators, adaptive motion filters are utilized to maximize the use of the available motion envelope of the motion system. However, not much is known about how the time-varying characteristics of such adaptive filters affect pilots when performing manual aircraft control. This paper presents the results of a study investigating the effects of time-varying motion filter gains on pilot control behavior and performance. An experiment was performed in a motion-base simulator where participants performed a simultaneous roll and pitch tracking task, while the roll and/or pitch motion filter gains changed over time. Results indicate that performance increases over time with increasing motion gains. This increase is a result of a time-varying adaptation of pilots' equalization dynamics, characterized by increased visual and motion response gains and decreased visual lead time constants. Opposite trends are found for decreasing motion filter gains. Even though the trends in both controlled axes are found to be largely the same, effects are less significant in roll. In addition, results indicate minor cross-coupling effects between pitch and roll, where a cueing variation in one axis affects the behavior adopted in the other axis.

The heat rate index indicator

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

Lasasso, M.; Runyan, B.; Napoli, J.

1995-06-01

This paper describes a method of tracking unit performance through the use of a reference number called the Heat Rate Index Indicator. The ABB Power Plant Controls OTIS performance monitor is used to determine when steady load conditions exist and then to collect controllable and equipment loss data which significantly impact thermal efficiency. By comparing these loss parameters to those found during the previous heat balance, it is possible to develop a new adjusted heat rate curve. These impacts on heat rate are used to changes the shape of the tested heat rate curve by the appropriate percentages over amore » specified load range. Mathcad is used to determine the Heat Rate Index by integrating for the areas beneath the adjusted heat rate curve and a heat rate curve that represents the unit`s ideal heat rate curve is the Heat Rate Index. An index of 1.0 indicates that the unit is operating at an ideal efficiency, while an index of less than 1.0 indicates that the unit is operating at less than ideal conditions. A one per cent change in the Heat Rate Index is equivalent to a one percent change in heat rate. The new shape of the adjusted heat rate curve and the individual curves generated from the controllable and equipment loss parameters are useful for determining performance problems in specific load ranges.« less

Anger, Violence, and Academic Performance: A Study of Troubled Minority Youth.

ERIC Educational Resources Information Center

Fleming, Jacqueline; Barner, Celious III; Hudson, Betsy; Rosignon-Carmouche, Lee A.

2000-01-01

Examined the relationship between anger, violence, and academic performance among troubled adolescents participating in a risk reduction intervention that stressed emotional confrontation and behavior change support. Surveys indicated that anger management was unrelated to violence or academic performance. Loss of control over time, concentration,…

Both texting and eating are associated with impaired simulated driving performance.

PubMed

Alosco, Michael L; Spitznagel, Mary Beth; Fischer, Kimberly Hall; Miller, Lindsay A; Pillai, Vivek; Hughes, Joel; Gunstad, John

2012-09-01

Distracted driving is a known contributor to traffic accidents, and many states have banned texting while driving. However, little is known about the potential accident risk of other common activities while driving, such as eating. The objective of the current study was to examine the adverse impact of eating/drinking behavior relative to texting and nondistracted behaviors on a simulated driving task. A total of 186 participants were recruited from undergraduate psychology courses over 2 semesters at Kent State University. We utilized the Kent Multidimensional Assessment Driving Simulation (K-MADS) to compare simulated driving performance among participants randomly assigned to texting (N = 45), eating (N = 45), and control (N = 96) conditions. Multivariate analyses of variance (MANOVA) were conducted to examine between-group differences on simulated driving indices. MANOVA analyses indicated that groups differed in simulated driving performance, F(14, 366) = 7.70, P < .001. Both texting and eating produced impaired driving performance relative to controls, though these behaviors had approximately equal effect. Specifically, both texting and eating groups had more collisions, pedestrian strikes, and center line crossings than controls. In addition, the texting group had more road edge excursions than either eating or control participants and the eating group missed more stop signs than controls. These findings suggest that both texting and eating are associated with poorer simulated driving performance. Future work is needed to determine whether these findings generalize to real-world driving and the development of strategies to reduce distracted driving.

A comprehensive analysis of the IMRT dose delivery process using statistical process control (SPC)

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

Gerard, Karine; Grandhaye, Jean-Pierre; Marchesi, Vincent

The aim of this study is to introduce tools to improve the security of each IMRT patient treatment by determining action levels for the dose delivery process. To achieve this, the patient-specific quality control results performed with an ionization chamber--and which characterize the dose delivery process--have been retrospectively analyzed using a method borrowed from industry: Statistical process control (SPC). The latter consisted in fulfilling four principal well-structured steps. The authors first quantified the short term variability of ionization chamber measurements regarding the clinical tolerances used in the cancer center ({+-}4% of deviation between the calculated and measured doses) by calculatingmore » a control process capability (C{sub pc}) index. The C{sub pc} index was found superior to 4, which implies that the observed variability of the dose delivery process is not biased by the short term variability of the measurement. Then, the authors demonstrated using a normality test that the quality control results could be approximated by a normal distribution with two parameters (mean and standard deviation). Finally, the authors used two complementary tools--control charts and performance indices--to thoroughly analyze the IMRT dose delivery process. Control charts aim at monitoring the process over time using statistical control limits to distinguish random (natural) variations from significant changes in the process, whereas performance indices aim at quantifying the ability of the process to produce data that are within the clinical tolerances, at a precise moment. The authors retrospectively showed that the analysis of three selected control charts (individual value, moving-range, and EWMA control charts) allowed efficient drift detection of the dose delivery process for prostate and head-and-neck treatments before the quality controls were outside the clinical tolerances. Therefore, when analyzed in real time, during quality controls, they should improve the security of treatments. They also showed that the dose delivery processes in the cancer center were in control for prostate and head-and-neck treatments. In parallel, long term process performance indices (P{sub p}, P{sub pk}, and P{sub pm}) have been analyzed. Their analysis helped defining which actions should be undertaken in order to improve the performance of the process. The prostate dose delivery process has been shown statistically capable (0.08% of the results is expected to be outside the clinical tolerances) contrary to the head-and-neck dose delivery process (5.76% of the results are expected to be outside the clinical tolerances).« less

A comprehensive analysis of the IMRT dose delivery process using statistical process control (SPC).

PubMed

Gérard, Karine; Grandhaye, Jean-Pierre; Marchesi, Vincent; Kafrouni, Hanna; Husson, François; Aletti, Pierre

2009-04-01

The aim of this study is to introduce tools to improve the security of each IMRT patient treatment by determining action levels for the dose delivery process. To achieve this, the patient-specific quality control results performed with an ionization chamber--and which characterize the dose delivery process--have been retrospectively analyzed using a method borrowed from industry: Statistical process control (SPC). The latter consisted in fulfilling four principal well-structured steps. The authors first quantified the short-term variability of ionization chamber measurements regarding the clinical tolerances used in the cancer center (+/- 4% of deviation between the calculated and measured doses) by calculating a control process capability (C(pc)) index. The C(pc) index was found superior to 4, which implies that the observed variability of the dose delivery process is not biased by the short-term variability of the measurement. Then, the authors demonstrated using a normality test that the quality control results could be approximated by a normal distribution with two parameters (mean and standard deviation). Finally, the authors used two complementary tools--control charts and performance indices--to thoroughly analyze the IMRT dose delivery process. Control charts aim at monitoring the process over time using statistical control limits to distinguish random (natural) variations from significant changes in the process, whereas performance indices aim at quantifying the ability of the process to produce data that are within the clinical tolerances, at a precise moment. The authors retrospectively showed that the analysis of three selected control charts (individual value, moving-range, and EWMA control charts) allowed efficient drift detection of the dose delivery process for prostate and head-and-neck treatments before the quality controls were outside the clinical tolerances. Therefore, when analyzed in real time, during quality controls, they should improve the security of treatments. They also showed that the dose delivery processes in the cancer center were in control for prostate and head-and-neck treatments. In parallel, long-term process performance indices (P(p), P(pk), and P(pm)) have been analyzed. Their analysis helped defining which actions should be undertaken in order to improve the performance of the process. The prostate dose delivery process has been shown statistically capable (0.08% of the results is expected to be outside the clinical tolerances) contrary to the head-and-neck dose delivery process (5.76% of the results are expected to be outside the clinical tolerances).

The effect of response modality on immediate serial recall in dementia of the Alzheimer type.

PubMed

Macé, Anne-Laure; Ergis, Anne-Marie; Caza, Nicole

2012-09-01

Contrary to traditional models of verbal short-term memory (STM), psycholinguistic accounts assume that temporary retention of verbal materials is an intrinsic property of word processing. Therefore, memory performance will depend on the nature of the STM tasks, which vary according to the linguistic representations they engage. The aim of this study was to explore the effect of response modality on verbal STM performance in individuals with dementia of the Alzheimer Type (DAT), and its relationship with the patients' word-processing deficits. Twenty individuals with mild DAT and 20 controls were tested on an immediate serial recall (ISR) task using the same items across two response modalities (oral and picture pointing) and completed a detailed language assessment. When scoring of ISR performance was based on item memory regardless of item order, a response modality effect was found for all participants, indicating that they recalled more items with picture pointing than with oral response. However, this effect was less marked in patients than in controls, resulting in an interaction. Interestingly, when recall of both item and order was considered, results indicated similar performance between response modalities in controls, whereas performance was worse for pointing than for oral response in patients. Picture-naming performance was also reduced in patients relative to controls. However, in the word-to-picture matching task, a similar pattern of responses was found between groups for incorrectly named pictures of the same items. The finding of a response modality effect in item memory for all participants is compatible with the assumption that semantic influences are greater in picture pointing than in oral response, as predicted by psycholinguistic models. Furthermore, patients' performance was modulated by their word-processing deficits, showing a reduced advantage relative to controls. Overall, the response modality effect observed in this study for item memory suggests that verbal STM performance is intrinsically linked with word processing capacities in both healthy controls and individuals with mild DAT, supporting psycholinguistic models of STM.

Handling properties of diverse automobiles and correlation with full scale response data. [driver/vehicle response to aerodynamic disturbances

NASA Technical Reports Server (NTRS)

Hoh, R. H.; Weir, D. H.

1973-01-01

Driver/vehicle response and performance of a variety of vehicles in the presence of aerodynamic disturbances are discussed. Steering control is emphasized. The vehicles include full size station wagon, sedan, compact sedan, van, pickup truck/camper, and wagon towing trailer. Driver/vehicle analyses are used to estimate response and performance. These estimates are correlated with full scale data with test drivers and the results are used to refine the driver/vehicle models, control structure, and loop closure criteria. The analyses and data indicate that the driver adjusts his steering control properties (when he can) to achieve roughly the same level of performance despite vehicle variations. For the more disturbance susceptible vehicles, such as the van, the driver tightens up his control. Other vehicles have handling dynamics which cause him to loosen his control response, even though performance degrades.

Crew Exploration Vehicle Launch Abort Controller Performance Analysis

NASA Technical Reports Server (NTRS)

Sparks, Dean W., Jr.; Raney, David L.

2007-01-01

This paper covers the simulation and evaluation of a controller design for the Crew Module (CM) Launch Abort System (LAS), to measure its ability to meet the abort performance requirements. The controller used in this study is a hybrid design, including features developed by the Government and the Contractor. Testing is done using two separate 6-degree-of-freedom (DOF) computer simulation implementations of the LAS/CM throughout the ascent trajectory: 1) executing a series of abort simulations along a nominal trajectory for the nominal LAS/CM system; and 2) using a series of Monte Carlo runs with perturbed initial flight conditions and perturbed system parameters. The performance of the controller is evaluated against a set of criteria, which is based upon the current functional requirements of the LAS. Preliminary analysis indicates that the performance of the present controller meets (with the exception of a few cases) the evaluation criteria mentioned above.

Gender differences in mathematics anxiety and the relation to mathematics performance while controlling for test anxiety

PubMed Central

2012-01-01

Background Mathematics anxiety (MA), a state of discomfort associated with performing mathematical tasks, is thought to affect a notable proportion of the school age population. Some research has indicated that MA negatively affects mathematics performance and that girls may report higher levels of MA than boys. On the other hand some research has indicated that boys’ mathematics performance is more negatively affected by MA than girls’ performance is. The aim of the current study was to measure girls’ and boys’ mathematics performance as well as their levels of MA while controlling for test anxiety (TA) a construct related to MA but which is typically not controlled for in MA studies. Methods Four-hundred and thirty three British secondary school children in school years 7, 8 and 10 completed customised mental mathematics tests and MA and TA questionnaires. Results No gender differences emerged for mathematics performance but levels of MA and TA were higher for girls than for boys. Girls and boys showed a positive correlation between MA and TA and a negative correlation between MA and mathematics performance. TA was also negatively correlated with mathematics performance, but this relationship was stronger for girls than for boys. When controlling for TA, the negative correlation between MA and performance remained for girls only. Regression analyses revealed that MA was a significant predictor of performance for girls but not for boys. Conclusions Our study has revealed that secondary school children experience MA. Importantly, we controlled for TA which is typically not controlled for in MA studies. Girls showed higher levels of MA than boys and high levels of MA were related to poorer levels of mathematics performance. As well as potentially having a detrimental effect on ‘online’ mathematics performance, past research has shown that high levels of MA can have negative consequences for later mathematics education. Therefore MA warrants attention in the mathematics classroom, particularly because there is evidence that MA develops during the primary school years. Furthermore, our study showed no gender difference in mathematics performance, despite girls reporting higher levels of MA. These results might suggest that girls may have had the potential to perform better than boys in mathematics however their performance may have been attenuated by their higher levels of MA. Longitudinal research is needed to investigate the development of MA and its effect on mathematics performance. PMID:22769743

Gender differences in mathematics anxiety and the relation to mathematics performance while controlling for test anxiety.

PubMed

Devine, Amy; Fawcett, Kayleigh; Szűcs, Dénes; Dowker, Ann

2012-07-09

Mathematics anxiety (MA), a state of discomfort associated with performing mathematical tasks, is thought to affect a notable proportion of the school age population. Some research has indicated that MA negatively affects mathematics performance and that girls may report higher levels of MA than boys. On the other hand some research has indicated that boys' mathematics performance is more negatively affected by MA than girls' performance is. The aim of the current study was to measure girls' and boys' mathematics performance as well as their levels of MA while controlling for test anxiety (TA) a construct related to MA but which is typically not controlled for in MA studies. Four-hundred and thirty three British secondary school children in school years 7, 8 and 10 completed customised mental mathematics tests and MA and TA questionnaires. No gender differences emerged for mathematics performance but levels of MA and TA were higher for girls than for boys. Girls and boys showed a positive correlation between MA and TA and a negative correlation between MA and mathematics performance. TA was also negatively correlated with mathematics performance, but this relationship was stronger for girls than for boys. When controlling for TA, the negative correlation between MA and performance remained for girls only. Regression analyses revealed that MA was a significant predictor of performance for girls but not for boys. Our study has revealed that secondary school children experience MA. Importantly, we controlled for TA which is typically not controlled for in MA studies. Girls showed higher levels of MA than boys and high levels of MA were related to poorer levels of mathematics performance. As well as potentially having a detrimental effect on 'online' mathematics performance, past research has shown that high levels of MA can have negative consequences for later mathematics education. Therefore MA warrants attention in the mathematics classroom, particularly because there is evidence that MA develops during the primary school years. Furthermore, our study showed no gender difference in mathematics performance, despite girls reporting higher levels of MA. These results might suggest that girls may have had the potential to perform better than boys in mathematics however their performance may have been attenuated by their higher levels of MA. Longitudinal research is needed to investigate the development of MA and its effect on mathematics performance.

Analysis of Salmonella control performance in U.S. young chicken slaughter and pork slaughter establishments.

PubMed

Muth, Mary K; Fahimi, Mansour; Karns, Shawn A

2009-01-01

In the 1996 U.S. Food Safety and Inspection Service's (FSIS) "Pathogen Reduction; Hazard Analysis and Critical Control Point (PR/HACCP) Systems, Final Rule," Salmonella was selected for microbiological testing and monitoring. Using data from an FSIS-sponsored survey of meat and poultry slaughter establishments, inspection results, and other establishment characteristics, potential variables affecting pathogen control, as measured by Salmonella test results, were investigated. The analysis data sets included 153 federally inspected young chicken slaughter establishments, of which 111 exceeded half the Salmonella performance standard at least once from 2003 through 2005, and 121 federally inspected pork slaughter establishments, of which 28 exceeded half the Salmonella performance standard. Logistic regression results for young chicken slaughter establishments indicate they were more likely to exceed half the standard if they had higher inspection noncompliance rates (P = 0.10) and older production space (P = 0.10), and were less likely to exceed it if they used a higher percentage of raw poultry inputs purchased from outside sources (P = 0.10). Results for pork slaughter establishments indicate they were more likely to exceed half the standard if they had a higher rate of voluntary microbiological testing (P = 0.08), and were less likely to exceed it if they were larger (P = 0.08) and used a higher percentage of raw pork inputs purchased from outside sources (P = 0.02). In general, indicators of plant characteristics, food safety practices, and management philosophy are associated with different levels of pathogen control performance that vary by species slaughtered.

A dynamic experimental study on the evaporative cooling performance of porous building materials

NASA Astrophysics Data System (ADS)

Zhang, Yu; Zhang, Lei; Meng, Qinglin; Feng, Yanshan; Chen, Yuanrui

2017-08-01

Conventional outdoor dynamic and indoor steady-state experiments have certain limitations in regard to investigating the evaporative cooling performance of porous building materials. The present study investigated the evaporative cooling performance of a porous building material using a special wind tunnel apparatus. First, the composition and control principles of the wind tunnel environment control system were elucidated. Then, the meteorological environment on a typical summer day in Guangzhou was reproduced in the wind tunnel and the evaporation process and thermal parameters of specimens composed of a porous building material were continuously measured. Finally, the experimental results were analysed to evaluate the accuracy of the wind tunnel environment control system, the heat budget of the external surface of the specimens and the total thermal resistance of the specimens and its uncertainty. The analysis results indicated that the normalized root-mean-square error between the measured value of each environmental parameter in the wind tunnel test section and the corresponding value input into the environment control system was <4%, indicating that the wind tunnel apparatus had relatively high accuracy in reproducing outdoor meteorological environments. In addition, the wet specimen could cumulatively consume approximately 80% of the shortwave radiation heat during the day, thereby reducing the temperature of the external surface and the heat flow on the internal surface of the specimen. Compared to the dry specimen, the total thermal resistance of the wet specimen was approximately doubled, indicating that the evaporation process of the porous building material could significantly improve the thermal insulation performance of the specimen.

Developing and implementing a computerized nursing quality control system in a tertiary general medical center in Israel.

PubMed

Kagan, Ilya; Cohen, Rachel; Fish, Miri; Mezare, Henia Perry

2014-01-01

This article describes the development and implementation of the Nursing Quality Indicators Scale and a quality control system for hospital nursing care, which allows universal access to all external and internal audit results, thus ensuring complete data transparency. Standardized indicators make departments' performance comparable. Key to the new system is nurses' self-audit and responsibility for making quality improvements at the ward level.

On the automaticity of response inhibition in individuals with alcoholism.

PubMed

Noël, Xavier; Brevers, Damien; Hanak, Catherine; Kornreich, Charles; Verbanck, Paul; Verbruggen, Frederick

2016-06-01

Response inhibition is usually considered a hallmark of executive control. However, recent work indicates that stop performance can become associatively mediated ('automatic') over practice. This study investigated automatic response inhibition in sober and recently detoxified individuals with alcoholism.. We administered to forty recently detoxified alcoholics and forty healthy participants a modified stop-signal task that consisted of a training phase in which a subset of the stimuli was consistently associated with stopping or going, and a test phase in which this mapping was reversed. In the training phase, stop performance improved for the consistent stop stimuli, compared with control stimuli that were not associated with going or stopping. In the test phase, go performance tended to be impaired for old stop stimuli. Combined, these findings support the automatic inhibition hypothesis. Importantly, performance was similar in both groups, which indicates that automatic inhibitory control develops normally in individuals with alcoholism.. This finding is specific to individuals with alcoholism without other psychiatric disorders, which is rather atypical and prevents generalization. Personalized stimuli with a stronger affective content should be used in future studies. These results advance our understanding of behavioral inhibition in individuals with alcoholism. Furthermore, intact automatic inhibitory control may be an important element of successful cognitive remediation of addictive behaviors.. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of MIL-L-23699 Lubricant Performance in the TF41-A-2 Engine

DTIC Science & Technology

1975-05-01

provides the necessary signals to the cockpit indicator for the indication of engine oil pressure. The differential pressure switch controls a cockpit...light. If the light is on, it indicates that the differential oil pressure is low. The setting ot the differential pressure switch is 11 t 1 psi. The

The association of health-related fitness with indicators of academic performance in Texas schools.

PubMed

Welk, Gregory J; Jackson, Allen W; Morrow, James R; Haskell, William H; Meredith, Marilu D; Cooper, Kenneth H

2010-09-01

This study examined the associations between indicators of health-related physical fitness (cardiovascular fitness and body mass index) and academic performance (Texas Assessment of Knowledge and Skills). Partial correlations were generally stronger for cardiovascular fitness than body mass index and consistently stronger in the middle school grades. Mixed-model regression analyses revealed modest associations between fitness and academic achievement after controlling for potentially confounding variables. The effects of fitness on academic achievement were positive but small. A separate logistic regression analysis indicated that higher fitness rates increased the odds of schools achieving exemplary/recognized school status within the state. School fitness attainment is an indicator of higher performing schools. Direction of causality cannot be inferred due to the cross-sectional nature of the data.

The effectiveness of training with an emergency department simulator on medical student performance in a simulated disaster.

PubMed

Franc-Law, Jeffrey Michael; Ingrassia, Pier Luigi; Ragazzoni, Luca; Della Corte, Francesco

2010-01-01

Training in practical aspects of disaster medicine is often impossible, and simulation may offer an educational opportunity superior to traditional didactic methods. We sought to determine whether exposure to an electronic simulation tool would improve the ability of medical students to manage a simulated disaster. We stratified 22 students by year of education and randomly assigned 50% from each category to form the intervention group, with the remaining 50% forming the control group. Both groups received the same didactic training sessions. The intervention group received additional disaster medicine training on a patient simulator (disastermed.ca), and the control group spent equal time on the simulator in a nondisaster setting. We compared markers of patient flow during a simulated disaster, including mean differences in time and number of patients to reach triage, bed assignment, patient assessment and disposition. In addition, we compared triage accuracy and scores on a structured command-and-control instrument. We collected data on the students' evaluations of the course for secondary purposes. Participants in the intervention group triaged their patients more quickly than participants in the control group (mean difference 43 s, 99.5% confidence interval [CI] 12 to 75 s). The score of performance indicators on a standardized scale was also significantly higher in the intervention group (18/18) when compared with the control group (8/18) (p < 0.001). All students indicated that they preferred the simulation-based curriculum to a lecture-based curriculum. When asked to rate the exercise overall, both groups gave a median score of 8 on a 10-point modified Likert scale. Participation in an electronic disaster simulation using the disastermed.ca software package appears to increase the speed at which medical students triage simulated patients and increase their score on a structured command-and-control performance indicator instrument. Participants indicated that the simulation-based curriculum in disaster medicine is preferable to a lecture-based curriculum. Overall student satisfaction with the simulation-based curriculum was high.

National Drug Control Strategy. FY 2009 Budget Summary

ERIC Educational Resources Information Center

The White House, 2008

2008-01-01

The National Drug Control Budget Summary identifies resources and performance indicators for programs within the Executive Branch that are integral to the President's National Drug Control Strategy. The Strategy, which is the Administration's plan for reducing drug use and availability, is based on three pillars: (1) Stopping Use Before It Starts,…

"Mind the gap!" Evaluation of the performance gap attributable to exception reporting and target thresholds in the new GMS contract: National database analysis.

PubMed

Fleetcroft, Robert; Steel, Nicholas; Cookson, Richard; Howe, Amanda

2008-06-17

The 2003 revision of the UK GMS contract rewards general practices for performance against clinical quality indicators. Practices can exempt patients from treatment, and can receive maximum payment for less than full coverage of eligible patients. This paper aims to estimate the gap between the percentage of maximum incentive gained and the percentage of patients receiving indicated care (the pay-performance gap), and to estimate how much of the gap is attributable respectively to thresholds and to exception reporting. Analysis of Quality Outcomes Framework data in the National Primary Care Database and exception reporting data from the Information Centre from 8407 practices in England in 2005 - 6. The main outcome measures were the gap between the percentage of maximum incentive gained and the percentage of patients receiving indicated care at the practice level, both for individual indicators and a combined composite score. An additional outcome was the percentage of that gap attributable respectively to exception reporting and maximum threshold targets set at less than 100%. The mean pay-performance gap for the 65 aggregated clinical indicators was 13.3% (range 2.9% to 48%). 52% of this gap (6.9% of eligible patients) is attributable to thresholds being set at less than 100%, and 48% to patients being exception reported. The gap was greater than 25% in 9 indicators: beta blockers and cholesterol control in heart disease; cholesterol control in stroke; influenza immunization in asthma; blood pressure, sugar and cholesterol control in diabetes; seizures in epilepsy and treatment of hypertension. Threshold targets and exception reporting introduce an incentive ceiling, which substantially reduces the percentage of eligible patients that UK practices need to treat in order to receive maximum incentive payments for delivering that care. There are good clinical reasons for exception reporting, but after unsuitable patients have been exempted from treatment, there is no reason why all maximum thresholds should not be 100%, whilst retaining the current lower thresholds to provide incentives for lower performing practices.

The Role of Motivation, Glucose and Self-Control in the Antisaccade Task

PubMed Central

Kelly, Claire L.; Sünram-Lea, Sandra I.; Crawford, Trevor J.

2015-01-01

Research shows that self-control is resource limited and there is a gradual weakening in consecutive self-control task performance akin to muscle fatigue. A body of evidence suggests that the resource is glucose and consuming glucose reduces this effect. This study examined the effect of glucose on performance in the antisaccade task - which requires self-control through generating a voluntary eye movement away from a target - following self-control exertion in the Stroop task. The effects of motivation and individual differences in self-control were also explored. In a double-blind design, 67 young healthy adults received a 25g glucose or inert placebo drink. Glucose did not enhance antisaccade performance following self-control exertion in the Stroop task. Motivation however, predicted performance on the antisaccade task; more specifically high motivation ameliorated performance decrements observed after initial self-control exertion. In addition, individuals with high levels of self-control performed better on certain aspects of the antisaccade task after administration of a glucose drink. The results of this study suggest that the antisaccade task might be a powerful paradigm, which could be used as a more objective measure of self-control. Moreover, the results indicate that level of motivation and individual differences in self-control should be taken into account when investigating deficiencies in self-control following prior exertion. PMID:25826334

Performance of Control System Using Microcontroller for Sea Water Circulation

NASA Astrophysics Data System (ADS)

Indriani, A.; Witanto, Y.; Pratama, A. S.; Supriyadi; Hendra; Tanjung, A.

2018-02-01

Now a day control system is very important rule for any process. Control system have been used in the automatic system. Automatic system can be seen in the industrial filed, mechanical field, electrical field and etc. In industrial and mechanical field, control system are used for control of motion component such as motor, conveyor, machine, control of process made of product, control of system and soon. In electrical field, control system can met for control of electrical system as equipment or part electrical like fan, rice cooker, refrigerator, air conditioner and etc. Control system are used for control of temperature and circulation gas, air and water. Control system of temperature and circulation of water also can be used for fisher community. Control system can be create by using microcontroller, PLC and other automatic program [1][2]. In this paper we will focus on the close loop system by using microcontroller Arduino Mega to control of temperature and circulation of sea water for fisher community. Performance control system is influenced by control equipment, sensor sensitivity, test condition, environment and others. The temperature sensor is measured using the DS18S20 and the sea water clarity sensor for circulation indicator with turbidity sensor. From the test results indicated that this control system can circulate sea water and maintain the temperature and clarity of seawater in a short time.

Digitized Spiral Drawing: A Possible Biomarker for Early Parkinson's Disease.

PubMed

San Luciano, Marta; Wang, Cuiling; Ortega, Roberto A; Yu, Qiping; Boschung, Sarah; Soto-Valencia, Jeannie; Bressman, Susan B; Lipton, Richard B; Pullman, Seth; Saunders-Pullman, Rachel

2016-01-01

Pre-clinical markers of Parkinson's Disease (PD) are needed, and to be relevant in pre-clinical disease, they should be quantifiably abnormal in early disease as well. Handwriting is impaired early in PD and can be evaluated using computerized analysis of drawn spirals, capturing kinematic, dynamic, and spatial abnormalities and calculating indices that quantify motor performance and disability. Digitized spiral drawing correlates with motor scores and may be more sensitive in detecting early changes than subjective ratings. However, whether changes in spiral drawing are abnormal compared with controls and whether changes are detected in early PD are unknown. 138 PD subjects (50 with early PD) and 150 controls drew spirals on a digitizing tablet, generating x, y, z (pressure) data-coordinates and time. Derived indices corresponded to overall spiral execution (severity), shape and kinematic irregularity (second order smoothness, first order zero-crossing), tightness, mean speed and variability of spiral width. Linear mixed effect adjusted models comparing these indices and cross-validation were performed. Receiver operating characteristic analysis was applied to examine discriminative validity of combined indices. All indices were significantly different between PD cases and controls, except for zero-crossing. A model using all indices had high discriminative validity (sensitivity = 0.86, specificity = 0.81). Discriminative validity was maintained in patients with early PD. Spiral analysis accurately discriminates subjects with PD and early PD from controls supporting a role as a promising quantitative biomarker. Further assessment is needed to determine whether spiral changes are PD specific compared with other disorders and if present in pre-clinical PD.

Digitized Spiral Drawing: A Possible Biomarker for Early Parkinson’s Disease

PubMed Central

San Luciano, Marta; Wang, Cuiling; Ortega, Roberto A.; Yu, Qiping; Boschung, Sarah; Soto-Valencia, Jeannie; Bressman, Susan B.; Lipton, Richard B.; Pullman, Seth; Saunders-Pullman, Rachel

2016-01-01

Introduction Pre-clinical markers of Parkinson’s Disease (PD) are needed, and to be relevant in pre-clinical disease, they should be quantifiably abnormal in early disease as well. Handwriting is impaired early in PD and can be evaluated using computerized analysis of drawn spirals, capturing kinematic, dynamic, and spatial abnormalities and calculating indices that quantify motor performance and disability. Digitized spiral drawing correlates with motor scores and may be more sensitive in detecting early changes than subjective ratings. However, whether changes in spiral drawing are abnormal compared with controls and whether changes are detected in early PD are unknown. Methods 138 PD subjects (50 with early PD) and 150 controls drew spirals on a digitizing tablet, generating x, y, z (pressure) data-coordinates and time. Derived indices corresponded to overall spiral execution (severity), shape and kinematic irregularity (second order smoothness, first order zero-crossing), tightness, mean speed and variability of spiral width. Linear mixed effect adjusted models comparing these indices and cross-validation were performed. Receiver operating characteristic analysis was applied to examine discriminative validity of combined indices. Results All indices were significantly different between PD cases and controls, except for zero-crossing. A model using all indices had high discriminative validity (sensitivity = 0.86, specificity = 0.81). Discriminative validity was maintained in patients with early PD. Conclusion Spiral analysis accurately discriminates subjects with PD and early PD from controls supporting a role as a promising quantitative biomarker. Further assessment is needed to determine whether spiral changes are PD specific compared with other disorders and if present in pre-clinical PD. PMID:27732597

Furthering the quality agenda in Aboriginal community controlled health services: understanding the relationship between accreditation, continuous quality improvement and national key performance indicator reporting.

PubMed

Sibthorpe, Beverly; Gardner, Karen; McAullay, Daniel

2016-01-01

A rapidly expanding interest in quality in the Aboriginal-community-controlled health sector has led to widespread uptake of accreditation using more than one set of standards, a proliferation of continuous quality improvement programs and the introduction of key performance indicators. As yet, there has been no overarching logic that shows how they relate to each other, with consequent confusion within and outside the sector. We map the three approaches to the Framework for Performance Assessment in Primary Health Care, demonstrating their key differences and complementarity. There needs to be greater attention in both policy and practice to the purposes and alignment of the three approaches if they are to embed a system-wide focus that supports quality improvement at the service level.

Nonlinear response of the anterior cingulate and prefrontal cortex in schizophrenia as a function of variable attentional control.

PubMed

Blasi, Giuseppe; Taurisano, Paolo; Papazacharias, Apostolos; Caforio, Grazia; Romano, Raffaella; Lobianco, Luciana; Fazio, Leonardo; Di Giorgio, Annabella; Latorre, Valeria; Sambataro, Fabio; Popolizio, Teresa; Nardini, Marcello; Mattay, Venkata S; Weinberger, Daniel R; Bertolino, Alessandro

2010-04-01

Previous studies have reported abnormal prefrontal and cingulate activity during attentional control processing in schizophrenia. However, it is not clear how variation in attentional control load modulates activity within these brain regions in this brain disorder. The aim of this study in schizophrenia is to investigate the impact of increasing levels of attentional control processing on prefrontal and cingulate activity. Blood oxygen level-dependent (BOLD) responses of 16 outpatients with schizophrenia were compared with those of 21 healthy subjects while performing a task eliciting increasing levels of attentional control during event-related functional magnetic resonance imaging at 3 T. Results showed reduced behavioral performance in patients at greater attentional control levels. Imaging data indicated greater prefrontal activity at intermediate attentional control levels in patients but greater prefrontal and cingulate responses at high attentional control demands in controls. The BOLD activity profile of these regions in controls increased linearly with increasing cognitive loads, whereas in patients, it was nonlinear. Correlation analysis consistently showed differential region and load-specific relationships between brain activity and behavior in the 2 groups. These results indicate that varying attentional control load is associated in schizophrenia with load- and region-specific modification of the relationship between behavior and brain activity, possibly suggesting earlier saturation of cognitive capacity.

Performance, Process, and Costs: Managing Service Quality with the Balanced Scorecard.

ERIC Educational Resources Information Center

Poll, Roswitha

2001-01-01

Describes a cooperative project among three German libraries that used the Balanced Scorecard as a concept for an integrated quality management system. Considers performance indicators across four perspectives that will help academic libraries establish an integrated controlling system and to collect and evaluate performance as well as cost data…

The Effect of Frequent Quizzes on Short- and Long-Term Academic Performance.

ERIC Educational Resources Information Center

Geist, James R.; Soehren, Stephen E.

1997-01-01

This study examined effects of frequent quizzes on dental student performance in a course on introductory radiology. Results indicated the group (N=36) with frequent quizzes performed significantly better than the control group (n=35) on midterm and final examinations (but not post-tests), and assessed course content and instructor more…

Delivery performance of conventional aircraft by terminal-area, time-based air traffic control: A real-time simulation evaluation

NASA Technical Reports Server (NTRS)

Credeur, Leonard; Houck, Jacob A.; Capron, William R.; Lohr, Gary W.

1990-01-01

A description and results are presented of a study to measure the performance and reaction of airline flight crews, in a full workload DC-9 cockpit, flying in a real-time simulation of an air traffic control (ATC) concept called Traffic Intelligence for the Management of Efficient Runway-scheduling (TIMER). Experimental objectives were to verify earlier fast-time TIMER time-delivery precision results and obtain data for the validation or refinement of existing computer models of pilot/airborne performance. Experimental data indicated a runway threshold, interarrival-time-error standard deviation in the range of 10.4 to 14.1 seconds. Other real-time system performance parameters measured include approach speeds, response time to controller turn instructions, bank angles employed, and ATC controller message delivery-time errors.

Perception of difficulty and glucose control: Effects on academic performance in youth with type I diabetes.

PubMed

Potts, Tiffany M; Nguyen, Jacqueline L; Ghai, Kanika; Li, Kathy; Perlmuter, Lawrence

2015-04-15

To investigate whether perceptions of task difficulty on neuropsychological tests predicted academic achievement after controlling for glucose levels and depression. Participants were type 1 diabetic adolescents, with a mean age = 12.5 years (23 females and 16 males), seen at a northwest suburban Chicago hospital. The sample population was free of co-morbid clinical health conditions. Subjects completed a three-part neuropsychological battery including the Digit Symbol Task, Trail Making Test, and Controlled Oral Word Association test. Following each task, individuals rated task difficulty and then completed a depression inventory. Performance on these three tests is reflective of neuropsychological status in relation to glucose control. Blood glucose levels were measured immediately prior to and after completing the neuropsychological battery using a glucose meter. HbA1c levels were obtained from medical records. Academic performance was based on self-reported grades in Math, Science, and English. Data was analyzed using multiple regression models to evaluate the associations between academic performance, perception of task difficulty, and glucose control. Perceptions of difficulty on a neuropsychological battery significantly predicted academic performance after accounting for glucose control and depression. Perceptions of difficulty on the neuropsychological tests were inversely correlated with academic performance (r = -0.48), while acute (blood glucose) and long-term glucose levels increased along with perceptions of task difficulty (r = 0.47). Additionally, higher depression scores were associated with poorer academic performance (r = -0.43). With the first regression analysis, perception of difficulty on the neuropsychological tasks contributed to 8% of the variance in academic performance after controlling for peripheral blood glucose and depression. In the second regression analysis, perception of difficulty accounted for 11% of the variance after accounting for academic performance and depression. The final regression analysis indicated that perception of difficulty increased with peripheral blood glucose, contributing to 22% of the variance. Most importantly, after controlling for perceptions of task difficulty, academic performance no longer predicted glucose levels. Finally, subjects who found the cognitive battery difficult were likely to have poor academic grades. Perceptions of difficulty on neurological tests exhibited a significant association with academic achievement, indicating that deficits in this skill may lead to academic disadvantage in diabetic patients.

Correlation between clinical and cognitive aspects and nutritional indicators of elderly patients with new-onset epilepsy.

PubMed

Tedrus, Gloria Maria A S; Screbenich, Silvana Mariana; Santos, Tamires Barbosa Nascimento

2018-06-20

Nutritional indicators were correlated with cognitive and clinical aspects of 25 elderly patients with new-onset epilepsy (EPWE). The nutritional indicators of the EPWE were compared with those of a similar control group at a significance level of p < 0.05. There was lower cognitive performance, greater risk of malnutrition and muscle tissue depletion, and higher waist circumference (WC) in the EPWE. Longer epilepsy duration was correlated with loss of muscle mass (Pearson's correlation: 0.433; p = 0.044). Performance in the verbal fluency test, in the clock-drawing test, and in the immediate memory test was negatively associated with body fat. Better performance in the image recognition test was negatively associated with the indicators of muscle reserve. There was lower cognitive performance, higher risk of malnutrition, and high abdominal obesity in EPWE. Cognitive performance was related to adiposity. Cognitive impairment and longer disease duration are related to increased nutritional risk. Copyright © 2018. Published by Elsevier Inc.

Performance Analysis of MYSEA

DTIC Science & Technology

2012-09-01

Services FSD Federated Services Daemon I&A Identification and Authentication IKE Internet Key Exchange KPI Key Performance Indicator LAN Local Area...spection takes place in different processes in the server architecture. Key Performance Indica- tor ( KPI )s associated with the system need to be...application and risk analysis of security controls. Thus, measurement of the KPIs is needed before an informed tradeoff between the performance penalties

Neuropsychological outcome in patients with childhood craniopharyngioma and hypothalamic involvement.

PubMed

Özyurt, Jale; Thiel, Christiane M; Lorenzen, Anna; Gebhardt, Ursel; Calaminus, Gabriele; Warmuth-Metz, Monika; Müller, Hermann L

2014-04-01

To test memory performance and executive functions in patients with childhood craniopharyngioma and hypothalamic involvement. Using standardized neuropsychological tests, we compared cognitive performance in a group of 15 patients with childhood craniopharyngioma and known hypothalamic involvement and a group of 24 age- and intelligence-matched control subjects. In addition, we compared individual patients' results with normative data to detect abnormal performance in the clinically relevant range. Within the patient group, we further tested whether the grade of hypothalamic involvement had an impact on cognitive performance and quality of life. Relative to healthy controls, the patients demonstrated significantly lower performance scores in tests of memory and executive functioning. On the individual performance level, delayed recall performance was severely impaired in one-third of the patients. Compared with patients with low-grade hypothalamic involvement, those with high-grade hypothalamic involvement showed worse performance in executive functions and reduced functional capabilities for daily life actions, indicating lower quality of life. Our findings demonstrate that hypothalamic involvement is related to impairments in memory and executive functioning in patients with childhood craniopharyngioma and indicate that a high grade of hypothalamic involvement is related to worse outcomes. Copyright © 2014 Mosby, Inc. All rights reserved.

How specific are emotional deficits? A comparison of empathic abilities in schizophrenia, bipolar and depressed patients

PubMed Central

Derntl, Birgit; Seidel, Eva-Maria; Schneider, Frank; Habel, Ute

2012-01-01

Empathy is a rather elaborated human ability and several recent studies highlight significant impairments in patients suffering from psychiatric disorders, such as schizophrenia, bipolar disorder or major depression. Therefore, the present study aimed at comparing behavioral empathy performance in schizophrenia, bipolar and depressed patients with healthy controls. All subjects performed three tasks tapping the core components of empathy: emotion recognition, emotional perspective taking and affective responsiveness. Groups were matched for age, gender, and verbal intelligence. Data analysis revealed three main findings: First, schizophrenia patients showed the strongest impairment in empathic performance followed by bipolar patients while depressed patients performed similar to controls in most tasks, except for affective responsiveness. Second, a significant association between clinical characteristics and empathy performance was only apparent in depression, indicating worse affective responsiveness with stronger symptom severity and longer duration of illness. Third, self-report data indicate that particularly bipolar patients describe themselves as less empathic, reporting less empathic concern and less perspective taking. Taken together, this study constitutes the first approach to directly compare specificity of empathic deficits in severe psychiatric disorders. Our results suggest disorder-specific impairments in emotional competencies that enable better characterization of the patient groups investigated and indicate different psychotherapeutic interventions. PMID:23116884

Intelligent automated control of life support systems using proportional representations.

PubMed

Wu, Annie S; Garibay, Ivan I

2004-06-01

Effective automatic control of Advanced Life Support Systems (ALSS) is a crucial component of space exploration. An ALSS is a coupled dynamical system which can be extremely sensitive and difficult to predict. As a result, such systems can be difficult to control using deliberative and deterministic methods. We investigate the performance of two machine learning algorithms, a genetic algorithm (GA) and a stochastic hill-climber (SH), on the problem of learning how to control an ALSS, and compare the impact of two different types of problem representations on the performance of both algorithms. We perform experiments on three ALSS optimization problems using five strategies with multiple variations of a proportional representation for a total of 120 experiments. Results indicate that although a proportional representation can effectively boost GA performance, it does not necessarily have the same effect on other algorithms such as SH. Results also support previous conclusions that multivector control strategies are an effective method for control of coupled dynamical systems.

When the going gets tough...: Self-motivation is associated with invigoration and fun.

PubMed

Kazén, Miguel; Kuhl, Julius; Leicht, Eva-Maria

2015-11-01

Personality systems interaction (PSI) theory postulates two executive control modes in volitional action: Self-control and self-regulation (self-motivation). Self-control should deplete energy whereas self-motivation should maintain energy and result in invigoration. There were three groups of participants: Self-control, self-motivation, and pretend, who performed a resource-demanding Stroop-Shift and an anagram task. Performance and energy expenditure were examined in each task. Compared to the other groups, the self-motivation group showed increments in blood glucose throughout the experiment, indicating invigoration, and had better performance on the difficult Stroop-Shift task than the self-control group. Additionally, for the self-motivation group anagram performance correlated with less effort and ease of concentration and was moderated by fun in the task. These results are consonant with the predictions of PSI and self-determination theories. It is concluded that self-control depletes resources whereas self-motivation is associated with invigoration in carrying resource-demanding tasks.

Control-display mapping in brain-computer interfaces.

PubMed

Thurlings, Marieke E; van Erp, Jan B F; Brouwer, Anne-Marie; Blankertz, Benjamin; Werkhoven, Peter

2012-01-01

Event-related potential (ERP) based brain-computer interfaces (BCIs) employ differences in brain responses to attended and ignored stimuli. When using a tactile ERP-BCI for navigation, mapping is required between navigation directions on a visual display and unambiguously corresponding tactile stimuli (tactors) from a tactile control device: control-display mapping (CDM). We investigated the effect of congruent (both display and control horizontal or both vertical) and incongruent (vertical display, horizontal control) CDMs on task performance, the ERP and potential BCI performance. Ten participants attended to a target (determined via CDM), in a stream of sequentially vibrating tactors. We show that congruent CDM yields best task performance, enhanced the P300 and results in increased estimated BCI performance. This suggests a reduced availability of attentional resources when operating an ERP-BCI with incongruent CDM. Additionally, we found an enhanced N2 for incongruent CDM, which indicates a conflict between visual display and tactile control orientations. Incongruency in control-display mapping reduces task performance. In this study, brain responses, task and system performance are related to (in)congruent mapping of command options and the corresponding stimuli in a brain-computer interface (BCI). Directional congruency reduces task errors, increases available attentional resources, improves BCI performance and thus facilitates human-computer interaction.

Depression of leukocyte protein synthesis, immune function and growth performance induced by high environmental temperature in broiler chickens

NASA Astrophysics Data System (ADS)

Kamel, Nancy N.; Ahmed, Ayman M. H.; Mehaisen, Gamal M. K.; Mashaly, Magdi M.; Abass, Ahmed O.

2017-09-01

In tropical and semitropical regions, raising broiler chickens out of their thermal comfort zone can cause an added economic loss in the poultry industry. The cause for the deleterious effects on immunity and growth performance of broilers under high environmental temperatures is still poorly understood. Therefore, the aim of the current investigation was to evaluate the effect of heat stress on leukocytes protein synthesis and immune function as a possible direct cause of low performance in broiler chickens under such condition. In this study, 300 one-day-old male broiler chicks (Cobb500™) were randomly assigned into 2 groups with 5 replicates of 30 chicks each. From 21 to 42 days of age, one group was exposed to non-stressed condition at 24 °C and 50% relative humidity (control group), while the other group was exposed to heat stress at 35 °C and 50% relative humidity (HS group). At 42 days of age, blood samples were collected from each group to evaluate stress indicators, immune function, and leukocytes protein synthesis. Production performance was also recorded. Noteworthy, protein synthesis in leukocytes was significantly ( P < 0.05) inhibited in HS group by 38% compared to control group. In contrast, the phosphorylation level on threonine 56 site (Thr56) of eukaryotic elongation factor (eEF2), which indicates the suppression of protein translation process through altering the protein elongation phase, was significantly threefold higher in HS group than in control ( P < 0.05). In addition, an increase in stress indicators was markedly ( P < 0.05) presented in the HS birds by twofold increase in heterophil/lymphocyte (H/L) ratio and threefold increase in plasma corticosterone level compared to control. Furthermore, the immune function was significantly ( P < 0.05) suppressed in HS birds than control (0.99 vs. 1.88 mg/mL plasma IgG, 89.2 vs. 148.0 μg/mL plasma IgM, 4.80 vs. 7.20 antibody titer against SRBC, and 1.38 vs. 3.39 stimulation index of lymphocyte proliferation in HS vs. control group, respectively). Moreover, results on the broiler performance indicate that HS birds had a significant ( P < 0.05) lower body weight gain by 58%, lower feed consumption by 39%, higher conversion ratio by 27%, and higher mortality by more than three times, compared to control birds. In conclusion, our results demonstrate that the inhibition of leukocyte protein synthesis through increasing the level of eEF2 Thr56 phosphorylation may play a key role in the observed decrease in immune function and growth performance with the high mortality rate encountered in broiler chickens under heat stress environment.

Analysis of Aircraft Control Performance using a Fuzzy Rule Base Representation of the Cooper-Harper Aircraft Handling Quality Rating

NASA Technical Reports Server (NTRS)

Tseng, Chris; Gupta, Pramod; Schumann, Johann

2006-01-01

The Cooper-Harper rating of Aircraft Handling Qualities has been adopted as a standard for measuring the performance of aircraft since it was introduced in 1966. Aircraft performance, ability to control the aircraft, and the degree of pilot compensation needed are three major key factors used in deciding the aircraft handling qualities in the Cooper- Harper rating. We formulate the Cooper-Harper rating scheme as a fuzzy rule-based system and use it to analyze the effectiveness of the aircraft controller. The automatic estimate of the system-level handling quality provides valuable up-to-date information for diagnostics and vehicle health management. Analyzing the performance of a controller requires a set of concise design requirements and performance criteria. Ir, the case of control systems fm a piloted aircraft, generally applicable quantitative design criteria are difficult to obtain. The reason for this is that the ultimate evaluation of a human-operated control system is necessarily subjective and, with aircraft, the pilot evaluates the aircraft in different ways depending on the type of the aircraft and the phase of flight. In most aerospace applications (e.g., for flight control systems), performance assessment is carried out in terms of handling qualities. Handling qualities may be defined as those dynamic and static properties of a vehicle that permit the pilot to fully exploit its performance in a variety of missions and roles. Traditionally, handling quality is measured using the Cooper-Harper rating and done subjectively by the human pilot. In this work, we have formulated the rules of the Cooper-Harper rating scheme as fuzzy rules with performance, control, and compensation as the antecedents, and pilot rating as the consequent. Appropriate direct measurements on the controller are related to the fuzzy Cooper-Harper rating system: a stability measurement like the rate of change of the cost function can be used as an indicator if the aircraft is under control; the tracking error is a good measurement for performance needed in the rating scheme. Finally, the change of the control amount or the output of a confidence tool, which has been developed by the authors, can be used as an indication of pilot compensation. We use a number of known aircraft flight scenarios with known pilot ratings to calibrate our fuzzy membership functions. These include normal flight conditions and situations in which partial or complete failure of tail, aileron, engine, or throttle occurs.

A Study on Application of Fuzzy Adaptive Unscented Kalman Filter to Nonlinear Turbojet Engine Control

NASA Astrophysics Data System (ADS)

Han, Dongju

2018-05-01

Safe and efficient flight powered by an aircraft turbojet engine relies on the performance of the engine controller preventing compressor surge with robustness from noises or disturbances. This paper proposes the effective nonlinear controller associated with the nonlinear filter for the real turbojet engine with highly nonlinear dynamics. For the feasible controller study the nonlinearity of the engine dynamics was investigated by comparing the step responses from the linearized model with the original nonlinear dynamics. The fuzzy-based PID control logic is introduced to control the engine efficiently and FAUKF is applied for robustness from noises. The simulation results prove the effectiveness of FAUKF applied to the proposed controller such that the control performances are superior over the conventional controller and the filer performance using FAUKF indicates the satisfactory results such as clearing the defects by reducing the distortions without compressor surge, whereas the conventional UKF is not fully effective as occurring some distortions with compressor surge due to a process noise.

Research in digital adaptive flight controllers

NASA Technical Reports Server (NTRS)

Kaufman, H.

1976-01-01

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

Objective but not subjective sleep predicts memory in community-dwelling older adults.

PubMed

Cavuoto, Marina G; Ong, Ben; Pike, Kerryn E; Nicholas, Christian L; Bei, Bei; Kinsella, Glynda J

2016-08-01

Research on the relationship between habitual sleep patterns and memory performance in older adults is limited. No previous study has used objective and subjective memory measures in a large, older-aged sample to examine the association between sleep and various domains of memory. The aim of this study was to examine the association between objective and subjective measures of sleep with memory performance in older adults, controlling for the effects of potential confounds. One-hundred and seventy-three community-dwelling older adults aged 65-89 years in Victoria, Australia completed the study. Objective sleep quality and length were ascertained using the Actiwatch 2 Mini-Mitter, while subjective sleep was measured using the Pittsburgh Sleep Quality Index. Memory was indexed by tests of retrospective memory (Hopkins Verbal Learning Test - Revised), working memory (n-back, 2-back accuracy) and prospective memory (a habitual button pressing task). Compared with normative data, overall performance on retrospective memory function was within the average range. Hierarchical regression was used to determine whether objective or subjective measures of sleep predicted memory performances after controlling for demographics, health and mood. After controlling for confounds, actigraphic sleep indices (greater wake after sleep onset, longer sleep-onset latency and longer total sleep time) predicted poorer retrospective (∆R(2)  = 0.05, P = 0.016) and working memory (∆R(2)  = 0.05, P = 0.047). In contrast, subjective sleep indices did not significantly predict memory performances. In community-based older adults, objectively-measured, habitual sleep indices predict poorer memory performances. It will be important to follow the sample longitudinally to determine trajectories of change over time. © 2016 European Sleep Research Society.

Electronic adherence monitoring device performance and patient acceptability: a randomized control trial.

PubMed

Chan, Amy Hai Yan; Stewart, Alistair William; Harrison, Jeff; Black, Peter Nigel; Mitchell, Edwin Arthur; Foster, Juliet Michelle

2017-05-01

To investigate the performance and patient acceptability of an inhaler electronic monitoring device in a real-world childhood asthma population. Children 6 to 15 years presenting with asthma to the hospital emergency department and prescribed inhaled corticosteroids were included. Participants were randomized to receive a device with reminder features enabled or disabled for use with their preventer. Device quality control tests were conducted. Questionnaires on device acceptability, utility and ergonomics were completed at six months. A total of 1306 quality control tests were conducted; 84% passed pre-issue and 87% return testing. The most common failure reason was actuation under-recording. Acceptability scores were high, with higher scores in the reminder than non-reminder group (median, 5 th -95 th percentile: 4.1, 3.1-5.0 versus 3.7, 2.3-4.8; p < 0.001). Most (>90%) rated the device easy to use. Feedback was positive across five themes: device acceptability, ringtone acceptability, suggestions for improvement, effect on medication use, and effect on asthma control. This study investigates electronic monitoring device performance and acceptability in children using quantitative and qualitative measures. Results indicate satisfactory reliability, although failure rates of 13-16% indicate the importance of quality control. Favorable acceptability ratings support the use of these devices in children.

Game-based training of flexibility and attention improves task-switch performance: near and far transfer of cognitive training in an EEG study.

PubMed

Olfers, Kerwin J F; Band, Guido P H

2018-01-01

There is a demand for ways to enhance cognitive flexibility, as it can be a limiting factor for performance in daily life. Video game training has been linked to advantages in cognitive functioning, raising the question if training with video games can promote cognitive flexibility. In the current study, we investigated if game-based computerized cognitive training (GCCT) could enhance cognitive flexibility in a healthy young adult sample (N = 72), as measured by task-switch performance. Three GCCT schedules were contrasted, which targeted: (1) cognitive flexibility and task switching, (2) attention and working memory, or (3) an active control involving basic math games, in twenty 45-min sessions across 4-6 weeks. Performance on an alternating-runs task-switch paradigm during pretest and posttest sessions indicated greater overall reaction time improvements after both flexibility and attention training as compared to control, although not related to local switch cost. Flexibility training enhanced performance in the presence of distractor-related interference. In contrast, attention training was beneficial when low task difficulty undermined sustained selective attention. Furthermore, flexibility training improved response selection as indicated by a larger N2 amplitude after training as compared to control, and more efficient conflict monitoring as indicated by reduced Nc/CRN and larger Pe amplitude after training. These results provide tentative support for the efficacy of GCCT and suggest that an ideal training might include both task switching and attention components, with maximal task diversity both within and between training games.

User's design handbook for a Standardized Control Module (SCM) for DC to DC Converters, volume 2

NASA Technical Reports Server (NTRS)

Lee, F. C.

1980-01-01

A unified design procedure is presented for selecting the key SCM control parameters for an arbitrarily given power stage configuration and parameter values, such that all regulator performance specifications can be met and optimized concurrently in a single design attempt. All key results and performance indices, for buck, boost, and buck/boost switching regulators which are relevant to SCM design considerations are included to facilitate frequent references.

Importance of perceptual representation in the visual control of action

NASA Astrophysics Data System (ADS)

Loomis, Jack M.; Beall, Andrew C.; Kelly, Jonathan W.; Macuga, Kristen L.

2005-03-01

In recent years, many experiments have demonstrated that optic flow is sufficient for visually controlled action, with the suggestion that perceptual representations of 3-D space are superfluous. In contrast, recent research in our lab indicates that some visually controlled actions, including some thought to be based on optic flow, are indeed mediated by perceptual representations. For example, we have demonstrated that people are able to perform complex spatial behaviors, like walking, driving, and object interception, in virtual environments which are rendered visible solely by cyclopean stimulation (random-dot cinematograms). In such situations, the absence of any retinal optic flow that is correlated with the objects and surfaces within the virtual environment means that people are using stereo-based perceptual representations to perform the behavior. The fact that people can perform such behaviors without training suggests that the perceptual representations are likely the same as those used when retinal optic flow is present. Other research indicates that optic flow, whether retinal or a more abstract property of the perceptual representation, is not the basis for postural control, because postural instability is related to perceived relative motion between self and the visual surroundings rather than to optic flow, even in the abstract sense.

Altered attentional control strategies but spared executive functioning in chronic cannabis users.

PubMed

Nusbaum, Amy T; Whitney, Paul; Cuttler, Carrie; Spradlin, Alexander; Hinson, John M; McLaughlin, Ryan J

2017-12-01

Cannabis use has increased rapidly in recent decades. The increase in cannabis use makes it important to understand the potential influence of chronic use on attentional control and other executive functions (EFs). Because cannabis is often used to reduce stress, and because stress can constrain attentional control and EFs, the primary goal of this study was to determine the joint effect of acute stress and chronic cannabis use on specific EFs. Thirty-nine cannabis users and 40 non-users were assigned to either a stress or no stress version of the Maastricht Acute Stress Test. Participants then completed two cognitive tasks that involve EFs: (1) task switching, and (2) a novel Flexible Attentional Control Task. These two tasks provided assessments of vigilant attention, inhibitory control, top-down attentional control, and cognitive flexibility. Salivary cortisol was assessed throughout the study. Reaction time indices showed an interaction between stress and cannabis use on top-down attentional control (p=0.036, n p 2 =0.059). Follow-up tests showed that cannabis users relied less on top-down attentional control than did non-users in the no stress version. Despite not relying on top-down control, the cannabis users showed no overall performance deficits on the tasks. Chronic cannabis users performed cognitive tasks involving EFs as well as non-users while not employing cognitive control processes that are typical for such tasks. These results indicate alterations in cognitive processing in cannabis users, but such alterations do not necessarily lead to global performance deficits. Copyright © 2017 Elsevier B.V. All rights reserved.

Electrophysiological indices of anterior cingulate cortex function reveal changing levels of cognitive effort and reward valuation that sustain task performance.

PubMed

Umemoto, Akina; Inzlicht, Michael; Holroyd, Clay B

2018-06-21

Successful execution of goal-directed behaviors often requires the deployment of cognitive control, which is thought to require cognitive effort. Recent theories have proposed that anterior cingulate cortex (ACC) regulates control levels by weighing the reward-related benefits of control against its effort-related costs. However, given that the sensations of cognitive effort and reward valuation are available only to introspection, this hypothesis is difficult to investigate empirically. We have proposed that two electrophysiological indices of ACC function, frontal midline theta and the reward positivity (RewP), provide objective measures of these functions. To explore this issue, we recorded the electroencephalogram (EEG) from participants engaged in an extended, cognitively-demanding task. Participants performed a time estimation task for 2 h in which they received reward and error feedback according to their task performance. We observed that the amplitude of the RewP, a feedback-locked component of the event related brain potential associated with reward processing, decreased with time-on-task. Conversely, frontal midline theta power, which consists of 4-8 Hz EEG oscillations associated with cognitive effort, increased with time-on-task. We also explored how these phenomena changed over time by conducting within-participant multi-level modeling analyses. Our results suggest that extended execution of a cognitively-demanding task is characterized by an early phase in which high control levels foster rapid improvements in task performance, and a later phase in which high control levels were necessary to maintain stable task performance, perhaps counteracting waning reward valuation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Advances in space robotics

NASA Technical Reports Server (NTRS)

Varsi, Giulio

1989-01-01

The problem of the remote control of space operations is addressed by identifying the key technical challenge: the management of contact forces and the principal performance parameters. Three principal classes of devices for remote operation are identified: anthropomorphic exoskeletons, computer aided teleoperators, and supervised telerobots. Their fields of application are described, and areas in which progress has reached the level of system or subsystem laboratory demonstrations are indicated. Key test results, indicating performance at a level useful for design tradeoffs, are reported.

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

NASA Technical Reports Server (NTRS)

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

1975-01-01

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

Interference Control, Working Memory Capacity, and Cognitive Abilities: A Latent Variable Analysis

ERIC Educational Resources Information Center

Unsworth, Nash

2010-01-01

The present study examined whether various indices of interference control were related to one another and to other cognitive abilities. It was found that the interference control measures were weakly correlated and could form a single factor that was related to overall memory performance on the tasks as well as to measures of working memory…

A Feasibility Study on the Control of a Generic Air Vehicle Using Control Moment Gyros

NASA Technical Reports Server (NTRS)

Lim, Kyong B.; Moerder, Daniel D.

2006-01-01

This paper examines feasibility and performance issues in using Control Moment Gyroscopes (CMGs) to control the attitude of a fixed-wing aircraft. The paper describes a control system structure that permits allocating control authority and bandwidth between a CMG system and conventional aerodynamic control surfaces to stabilize a vehicle with neutral aerodynamic stability. A simulation study explores the interplay between aerodynamic and CMG effects, and indicates desirable physical characteristics for a CMG system to be used for aircraft attitude control.

Motion and Form Coherence Detection in Autistic Spectrum Disorder: Relationship to Motor Control and 2:4 Digit Ratio

ERIC Educational Resources Information Center

Milne, Elizabeth; White, Sarah; Campbell, Ruth; Swettenham, John; Hansen, Peter; Ramus, Franck

2006-01-01

Children with autistic spectrum disorder and controls performed tasks of coherent motion and form detection, and motor control. Additionally, the ratio of the 2nd and 4th digits of these children, which is thought to be an indicator of foetal testosterone, was measured. Children in the experimental group were impaired at tasks of motor control,…

Autonomy and control in dyads: effects on interaction quality and joint creative performance.

PubMed

Weinstein, Netta; Hodgins, Holley S; Ryan, Richard M

2010-12-01

Two studies examined interaction quality and joint performance on two creative tasks in unacquainted dyads primed for autonomy or control orientations. It was hypothesized that autonomy-primed dyads would interact more constructively, experience more positive mood, and engage the task more readily, and as a result these dyads would perform better. To test this, Study 1 primed orientation and explored verbal creative performance on the Remote Associates Task (RAT). In Study 2, dyads were primed with autonomy and control orientation and videotaped during two joint creative tasks, one verbal (RAT) and one nonverbal (charades). Videotapes were coded for behavioral indicators of closeness and task engagement. Results showed that autonomy-primed dyads felt closer, were more emotionally and cognitively attuned, provided empathy and encouragement to partners, and performed more effectively. The effects of primed autonomy on creative performance were mediated by interpersonal quality, mood, and joint engagement.

The effects of in-vehicle tasks and time-gap selection while reclaiming control from adaptive cruise control (ACC) with bus simulator.

PubMed

Lin, Tsang-Wei; Hwang, Sheue-Ling; Su, Jau-Ming; Chen, Wan-Hui

2008-05-01

This research aimed to find out the effects of in-vehicle distractions and time-gap settings with a fix-based bus driving simulator in a following scenario. Professional bus drivers were recruited to perform in-vehicle tasks while driving with adaptive cruise control (ACC) of changeable time-gap settings in freeway traffic. Thirty subjects were divided equally into three groups for different in-vehicle task modes (between subjects), including no task distraction, hands-free, and manual modes. Further, time-gap settings for the experimental ACC were: shorter than 1.0 s, 1.0-1.5 s, 1.5-2.0 s, and longer than 2.0 s (within subjects). Longitudinal (mean headway, forward collision rate, and response time) and lateral control (mean lateral lane position and its standard deviation) performance was assessed. In the results, longitudinal control performance was worsened by both shorter time-gaps and heavier in-vehicle tasks. But the interaction indicated that the harm by heavier in-vehicle distraction could be improved by longer time-gaps. As for the lateral control, it would only be negatively affected by shorter time-gap settings. This research indicates the effects of time-gaps and in-vehicle distraction, as well as the interaction. Proper time-gap selection under different in-vehicle distractions can help avoid accidents and keep safe.

Are Hypertensives Less Assertive? A Controlled Evaluation.

ERIC Educational Resources Information Center

Keane, Terence M.; And Others

1982-01-01

Assessed the performance of hypertensive patients in increasingly demanding interpersonal interactions. Twelve extended role-played scenes were employed. Results indicated that the hypertensive patients responded less assertively than the nonpatient comparison group. However, the performance of the normotensive patient group was similar to that of…

New operator assistance features in the CMS Run Control System

NASA Astrophysics Data System (ADS)

Andre, J.-M.; Behrens, U.; Branson, J.; Brummer, P.; Chaze, O.; Cittolin, S.; Contescu, C.; Craigs, B. G.; Darlea, G.-L.; Deldicque, C.; Demiragli, Z.; Dobson, M.; Doualot, N.; Erhan, S.; Fulcher, J. R.; Gigi, D.; Gładki, M.; Glege, F.; Gomez-Ceballos, G.; Hegeman, J.; Holzner, A.; Janulis, M.; Jimenez-Estupiñán, R.; Masetti, L.; Meijers, F.; Meschi, E.; Mommsen, R. K.; Morovic, S.; O'Dell, V.; Orsini, L.; Paus, C.; Petrova, P.; Pieri, M.; Racz, A.; Reis, T.; Sakulin, H.; Schwick, C.; Simelevicius, D.; Vougioukas, M.; Zejdl, P.

2017-10-01

During Run-1 of the LHC, many operational procedures have been automated in the run control system of the Compact Muon Solenoid (CMS) experiment. When detector high voltages are ramped up or down or upon certain beam mode changes of the LHC, the DAQ system is automatically partially reconfigured with new parameters. Certain types of errors such as errors caused by single-event upsets may trigger an automatic recovery procedure. Furthermore, the top-level control node continuously performs cross-checks to detect sub-system actions becoming necessary because of changes in configuration keys, changes in the set of included front-end drivers or because of potential clock instabilities. The operator is guided to perform the necessary actions through graphical indicators displayed next to the relevant command buttons in the user interface. Through these indicators, consistent configuration of CMS is ensured. However, manually following the indicators can still be inefficient at times. A new assistant to the operator has therefore been developed that can automatically perform all the necessary actions in a streamlined order. If additional problems arise, the new assistant tries to automatically recover from these. With the new assistant, a run can be started from any state of the sub-systems with a single click. An ongoing run may be recovered with a single click, once the appropriate recovery action has been selected. We review the automation features of CMS Run Control and discuss the new assistant in detail including first operational experience.

New Operator Assistance Features in the CMS Run Control System

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

Andre, J.M.; et al.

During Run-1 of the LHC, many operational procedures have been automated in the run control system of the Compact Muon Solenoid (CMS) experiment. When detector high voltages are ramped up or down or upon certain beam mode changes of the LHC, the DAQ system is automatically partially reconfigured with new parameters. Certain types of errors such as errors caused by single-event upsets may trigger an automatic recovery procedure. Furthermore, the top-level control node continuously performs cross-checks to detect sub-system actions becoming necessary because of changes in configuration keys, changes in the set of included front-end drivers or because of potentialmore » clock instabilities. The operator is guided to perform the necessary actions through graphical indicators displayed next to the relevant command buttons in the user interface. Through these indicators, consistent configuration of CMS is ensured. However, manually following the indicators can still be inefficient at times. A new assistant to the operator has therefore been developed that can automatically perform all the necessary actions in a streamlined order. If additional problems arise, the new assistant tries to automatically recover from these. With the new assistant, a run can be started from any state of the sub-systems with a single click. An ongoing run may be recovered with a single click, once the appropriate recovery action has been selected. We review the automation features of CMS Run Control and discuss the new assistant in detail including first operational experience.« less

Cockpit integration from a pilot's point of view

NASA Technical Reports Server (NTRS)

Green, D. L.

1982-01-01

Extensive experience in both operational and engineering test flight was used to suggest straightforward changes to helicopter cockpit and control system design that would improve pilot performance in marginal and instrument flight conditions. Needed control system improvements considered include: (1) separation of yaw from cyclic force trim; (2) pedal force proportional to displacement rate; and (3) integration of engine controls in collective stick. Display improvements needed include: (1) natural cuing of yaw rate in attitude indicator; (2) collective position indication and radar altimeter placed within primary scan; and (3) omnidirectional display of full range airspeed data.

Blatant Stereotype Threat and Women's Math Performance: Self-Handicapping as a Strategic Means To Cope with Obtrusive Negative Performance Expectations.

ERIC Educational Resources Information Center

Keller, Johannes

2002-01-01

Examined the impact of increased salience of negative stereotypic expectations on math performance among high school students. Results indicated that female students in the condition of heightened salience of negative stereotypic expectations underperformed in comparison to their control group counterparts. The effect of blatant stereotype threat…

Creativity on tap? Effects of alcohol intoxication on creative cognition

PubMed Central

Benedek, Mathias; Panzierer, Lisa; Jauk, Emanuel; Neubauer, Aljoscha C.

2017-01-01

Anecdotal reports link alcohol intoxication to creativity, while cognitive research highlights the crucial role of cognitive control for creative thought. This study examined the effects of mild alcohol intoxication on creative cognition in a placebo-controlled design. Participants completed executive and creative cognition tasks before and after consuming either alcoholic beer (BAC of 0.03) or non-alcoholic beer (placebo). Alcohol impaired executive control, but improved performance in the Remote Associates Test, and did not affect divergent thinking ability. The findings indicate that certain aspects of creative cognition benefit from mild attenuations of cognitive control, and contribute to the growing evidence that higher cognitive control is not always associated with better cognitive performance. PMID:28705663

High-power microwave generation using optically activated semiconductor switches

NASA Astrophysics Data System (ADS)

Nunnally, William C.

1990-12-01

The two prominent types of optically controlled switches, the optically controlled linear (OCL) switch and the optically initiated avalanche (OIA) switch, are described, and their operating parameters are characterized. Two transmission line approaches, one using a frozen-wave generator and the other using an injected-wave generator, for generation of multiple cycles of high-power microwave energy using optically controlled switches are discussed. The point design performances of the series-switch, frozen-wave generator and the parallel-switch, injected-wave generator are compared. The operating and performance limitations of the optically controlled switch types are discussed, and additional research needed to advance the development of the optically controlled, bulk, semiconductor switches is indicated.

An Adaptive Supervisory Sliding Fuzzy Cerebellar Model Articulation Controller for Sensorless Vector-Controlled Induction Motor Drive Systems

PubMed Central

Wang, Shun-Yuan; Tseng, Chwan-Lu; Lin, Shou-Chuang; Chiu, Chun-Jung; Chou, Jen-Hsiang

2015-01-01

This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC) in the speed sensorless vector control of an induction motor (IM) drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes—the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC—were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE) was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes. PMID:25815450

An adaptive supervisory sliding fuzzy cerebellar model articulation controller for sensorless vector-controlled induction motor drive systems.

PubMed

Wang, Shun-Yuan; Tseng, Chwan-Lu; Lin, Shou-Chuang; Chiu, Chun-Jung; Chou, Jen-Hsiang

2015-03-25

This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC) in the speed sensorless vector control of an induction motor (IM) drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes--the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC--were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE) was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes.

Standardization of quality control plans for highway bridges in Europe: COST Action TU 1406

NASA Astrophysics Data System (ADS)

Casas, Joan R.; Matos, Jose Campos e.

2017-09-01

In Europe, as all over the world, the need to manage roadway bridges in an efficient way led to the development of different management systems. Hence, nowadays, many European countries have their own system. Although they present a similar architectural framework, several differences can be appointed. These differences constitute a divergent mechanism that may conduct to different decisions on maintenance actions. Within the roadway bridge management process, the identification of maintenance needs is more effective when developed in a uniform and repeatable manner. This process can be accomplished by the identification of performance indicators and definition of performance goals and key performance indicators (KPI), improving the planning of maintenance strategies. Therefore, a discussion at a European level, seeking to achieve a standardized approach in this subject, will bring significant benefits. Accordingly, a COST Action is under way in Europe with the aim of standardizing the establishment of quality control plans for roadway bridges.

Number and placement of control system components considering possible failures. [for large space structures

NASA Technical Reports Server (NTRS)

Vander Velde, W. E.; Carignan, C. R.

1984-01-01

One of the first questions facing the designer of the control system for a large space structure is how many components actuators and sensors - to specify and where to place them on the structure. This paper presents a methodology which is intended to assist the designer in making these choices. A measure of controllability is defined which is a quantitative indication of how well the system can be controlled with a given set of actuators. Similarly, a measure of observability is defined which is a quantitative indication of how well the system can be observed with a given set of sensors. Then the effect of component unreliability is introduced by computing the average expected degree of controllability (observability) over the operating lifetime of the system accounting for the likelihood of various combinations of component failures. The problem of component location is resolved by optimizing this performance measure over the admissible set of locations. The variation of this optimized performance measure with number of actuators (sensors) is helpful in deciding how many components to use.

Active structural acoustic control of noise transmission through double panel systems

NASA Astrophysics Data System (ADS)

Carneal, James P.; Fuller, Chris R.

1995-04-01

A preliminary parametric study of active control of sound transmission through double panel systems has been experimentally performed. The technique used is the active structural acoustic control (ASAC) approach where control inputs, in the form of piezoelectric actuators, were applied to the structure while the radiated pressure field was minimized. Results indicate the application of control inputs to the radiating panel resulted in greater transmission loss due to its direct effect on the nature of the structural-acoustic coupling between the radiating panel and the receiving chamber. Increased control performance was seen in a double panel system consisting of a stiffer radiating panel with a lower modal density. As expected, more effective control of a radiating panel excited on-resonance is achieved over one excited off-resonance. In general, the results validate the ASAC approach for double panel systems and demonstrate that it is possible to take advantage of double panel behavior to enhance control performance, although it is clear that further research must be done to understand the physics involved.

Training Attention Improves Decision Making in Individuals with Elevated Self-Reported Depressive Symptoms

PubMed Central

Cooper, Jessica A.; Gorlick, Marissa A.; Denny, Taylor; Worthy, Darrell A.; Beevers, Christopher G.; Maddox, W. Todd

2013-01-01

Depression is often characterized by attentional biases toward negative items and away from positive items, which likely affects reward and punishment processing. Recent work reported that training attention away from negative stimuli reduced this bias and reduced depressive symptoms. However, the effect of attention training on subsequent learning has yet to be explored. In the current study, participants were required to learn to maximize reward during decision-making. Undergraduates with elevated self-reported depressive symptoms received attention training toward positive stimuli prior to performing the decision-making task (n=20; active training). The active training group was compared to two groups: undergraduates with elevated self-reported depressive symptoms who received placebo training (n=22; placebo training) and control subjects with low levels of depressive symptoms (n=33; non-depressive control). The placebo-training depressive group performed worse and switched between options more than non-depressive controls on the reward maximization task. However, depressives that received active training performed as well as non-depressive controls. Computational modeling indicated that the placebo-trained group learned more from negative than from positive prediction errors, leading to more frequent switching. The non-depressive control and active training depressive groups showed similar learning from positive and negative prediction errors, leading to less frequent switching and better performance. Our results indicate that individuals with elevated depressive symptoms are impaired at reward maximization, but that the deficit can be improved with attention training toward positive stimuli. PMID:24197612

Training attention improves decision making in individuals with elevated self-reported depressive symptoms.

PubMed

Cooper, Jessica A; Gorlick, Marissa A; Denny, Taylor; Worthy, Darrell A; Beevers, Christopher G; Maddox, W Todd

2014-06-01

Depression is often characterized by attentional biases toward negative items and away from positive items, which likely affects reward and punishment processing. Recent work has reported that training attention away from negative stimuli reduced this bias and reduced depressive symptoms. However, the effect of attention training on subsequent learning has yet to be explored. In the present study, participants were required to learn to maximize reward during decision making. Undergraduates with elevated self-reported depressive symptoms received attention training toward positive stimuli prior to performing the decision-making task (n = 20; active training). The active-training group was compared to two other groups: undergraduates with elevated self-reported depressive symptoms who received placebo training (n = 22; placebo training) and a control group with low levels of depressive symptoms (n = 33; nondepressive control). The placebo-training depressive group performed worse and switched between options more than did the nondepressive controls on the reward maximization task. However, depressives that received active training performed as well as the nondepressive controls. Computational modeling indicated that the placebo-trained group learned more from negative than from positive prediction errors, leading to more frequent switching. The nondepressive control and active-training depressive groups showed similar learning from positive and negative prediction errors, leading to less-frequent switching and better performance. Our results indicate that individuals with elevated depressive symptoms are impaired at reward maximization, but that the deficit can be improved with attention training toward positive stimuli.

Health Indicators: A Tool for Program Review

ERIC Educational Resources Information Center

Abou-Sayf, Frank K.

2006-01-01

A visual tool used to evaluate instructional program performance has been designed by the University of Hawaii Community College system. The tool combines features from traffic lights, blood-chemistry test reports, and industry production control charts, and is labeled the Program Health-Indicator Chart. The tool was designed to minimize the labor…

Time-History Data of Maneuvers Performed by an F-86A Airplane During Squadron Operational Training

NASA Technical Reports Server (NTRS)

Henderson, Campbell; Thornton, James; Mayo, Alton

1952-01-01

Preliminary results of one phase of a control-motion study program are presented in the form of plots of load factor.and angular acceleration against indicated airspeed and of time histories of several measured quantities. The results were obtained from 197 maneuvers performed by an F-86A jet-fighter airplane during normal squadron operational training. Most of the tactical maneuver8 of which the F-86A is capable were performed at pressure altitudes ranging from 0 to 32,000 feet and at indicated airspeeds ranging from 95 to 650 miles per hour.

Modeling of Karachaganak field development

NASA Astrophysics Data System (ADS)

Sadvakasov, A. A.; Shamsutdinova, G. F.; Almukhametova, E. M.; Gabdrakhmanov, N. Kh

2018-05-01

Management of a geological deposit includes the study and analysis of oil recovery, identification of factors influencing production performance and oil-bearing rock flooding, reserve recovery and other indicators characterizing field development in general. Regulation of oil deposits exploitation is a mere control over the fluid flow within a reservoir, which is ensured through the designed system of development via continuous improvement of production and injection wells placement, optimum performance modes, service conditions of downhole and surface oil-field equipment taking into account various changes and physical-geological properties of a field when using modern equipment to obtain the best performance indicators.

Design of an unified chassis controller for rollover prevention, manoeuvrability and lateral stability

NASA Astrophysics Data System (ADS)

Yoon, Jangyeol; Yim, Seongjin; Cho, Wanki; Koo, Bongyeong; Yi, Kyongsu

2010-11-01

This paper describes a unified chassis control (UCC) strategy to prevent vehicle rollover and improve both manoeuvrability and lateral stability. Since previous researches on rollover prevention are only focused on the reduction of lateral acceleration, the manoeuvrability and lateral stability cannot be guaranteed. For this reason, it is necessary to design a UCC controller to prevent rollover and improve lateral stability by integrating electronic stability control, active front steering and continuous damping control. This integration is performed through switching among several control modes and a simulation is performed to validate the proposed method. Simulation results indicate that a significant improvement in rollover prevention, manoeuvrability and lateral stability can be expected from the proposed UCC system.

Effect of a population-level performance dashboard intervention on maternal-newborn outcomes: an interrupted time series study.

PubMed

Weiss, Deborah; Dunn, Sandra I; Sprague, Ann E; Fell, Deshayne B; Grimshaw, Jeremy M; Darling, Elizabeth; Graham, Ian D; Harrold, JoAnn; Smith, Graeme N; Peterson, Wendy E; Reszel, Jessica; Lanes, Andrea; Walker, Mark C; Taljaard, Monica

2018-06-01

To assess the effect of the Maternal Newborn Dashboard on six key clinical performance indicators in the province of Ontario, Canada. Interrupted time series using population-based data from the provincial birth registry covering a 3-year period before implementation of the Dashboard and 2.5 years after implementation (November 2009 through March 2015). All hospitals in the province of Ontario providing maternal-newborn care (n=94). A hospital-based online audit and feedback programme. Rates of the six performance indicators included in the Dashboard. 2.5 years after implementation, the audit and feedback programme was associated with statistically significant absolute decreases in the rates of episiotomy (decrease of 1.5 per 100 women, 95% CI 0.64 to 2.39), induction for postdates in women who were less than 41 weeks at delivery (decrease of 11.7 per 100 women, 95% CI 7.4 to 16.0), repeat caesarean delivery in low-risk women performed before 39 weeks (decrease of 10.4 per 100 women, 95% CI 9.3 to 11.5) and an absolute increase in the rate of appropriately timed group B streptococcus screening (increase of 2.8 per 100, 95% CI 2.2 to 3.5). The audit and feedback programme did not significantly affect the rates of unsatisfactory newborn screening blood samples or formula supplementation at discharge. No statistically significant effects were observed for the two internal control outcomes or the four external control indicators-in fact, two external control indicators (episiotomy and postdates induction) worsened relative to before implementation. An electronic audit and feedback programme implemented in maternal-newborn hospitals was associated with clinically relevant practice improvements at the provincial level in the majority of targeted indicators. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The effects of teacher anxiety and modeling on the acquisition of a science teaching skill and concomitant student performance

NASA Astrophysics Data System (ADS)

Koran, John J., Jr.; Koran, Mary Lou

In a study designed to explore the effects of teacher anxiety and modeling on acquisition of a science teaching skill and concomitant student performance, 69 preservice secondary teachers and 295 eighth grade students were randomly assigned to microteaching sessions. Prior to microteaching, teachers were given an anxiety test, then randomly assigned to one of three treatments; a transcript model, a protocol model, or a control condition. Subsequently both teacher and student performance was assessed using written and behavioral measures. Analysis of variance indicated that subjects in the two modeling treatments significantly exceeded performance of control group subjects on all measures of the dependent variable, with the protocol model being generally superior to the transcript model. The differential effects of the modeling treatments were further reflected in student performance. Regression analysis of aptitude-treatment interactions indicated that teacher anxiety scores interacted significantly with instructional treatments, with high anxiety teachers performing best in the protocol modeling treatment. Again, this interaction was reflected in student performance, where students taught by highly anxious teachers performed significantly better when their teachers had received the protocol model. These results were discussed in terms of teacher concerns and a memory model of the effects of anxiety on performance.

Fixture congestion modulates post-match recovery kinetics in professional soccer players.

PubMed

Lundberg, Tommy R; Weckström, Kristoffer

2017-01-01

This study examined the influence of fixture congestion on physical performance and biochemical variables in professional male footballers. After 3 competitive matches within a week (3M cycle), 16 players underwent blood sampling and field testing 72 h after the last match. The same tests were performed after a regular 1 match-week cycle (1M cycle). The 1M vs. 3M change scores were compared between Congested (high match exposure) and non-selected Control players. The change score in muscle soreness was greater (effect size 1.0; CI 0.0-1.9) in the Congested players than Controls, indicating a possible negative effect of fixture congestion. There were no effects on sprint and jump performance. The change in plasma (P)-Urea was greater in Congested players than controls (effect size 1.3; CI 0.3-2.2). The effects on other blood variables were either non-existing/trivial, or unclear. Altogether, physical fitness and immune function were not compromised by match congestion, yet some indices of physiological stress and muscle damage were still evident.

Flight investigation of manual and automatic VTOL decelerating instrument approaches and landings

NASA Technical Reports Server (NTRS)

Kelly, J. R.; Niessen, F. R.; Thibodeaux, J. J.; Yenni, K. R.; Garren, J. F., Jr.

1974-01-01

A flight investigation was undertaken to study the problems associated with manual and automatic control of steep, decelerating instrument approaches and landings under simulated instrument conditions. The study was conducted with a research helicopter equipped with a three-cue flight-director indicator. The scope of the investigation included variations in the flight-director control laws, glide-path angle, deceleration profile, and control response characteristics. Investigation of the automatic-control problem resulted in the first automated approach and landing to a predetermined spot ever accomplished with a helicopter. Although well-controlled approaches and landings could be performed manually with the flight-director concept, pilot comments indicated the need for a better display which would more effectively integrate command and situation information.

Experimental parametric study of jet vortex generators for flow separation control

NASA Technical Reports Server (NTRS)

Selby, Gregory

1991-01-01

A parametric wind-tunnel study was performed with jet vortex generators to determine their effectiveness in controlling flow separation associated with low-speed turbulence flow over a two-dimensional rearward-facing ramp. Results indicate that flow-separation control can be accomplished, with the level of control achieved being a function of jet speed, jet orientation (with respect to the free-stream direction), and orifice pattern (double row of jets vs. single row). Compared to slot blowing, jet vortex generators can provide an equivalent level of flow control over a larger spanwise region (for constant jet flow area and speed). Dye flow visualization tests in a water tunnel indicated that the most effective jet vortex generator configurations produced streamwise co-rotating vortices.

Association between attempted suicide and academic performance indicators among middle and high school students in Mexico: results from a national survey.

PubMed

Orozco, Ricardo; Benjet, Corina; Borges, Guilherme; Moneta Arce, María Fátima; Fregoso Ito, Diana; Fleiz, Clara; Villatoro, Jorge Ameth

2018-01-01

Students' mental health is associated to academic performance. In high income countries, higher students' grades are related to lower odds of suicidal behaviors, but studies on other indicators of academic performance are more limited, specially in middle income countries. Data from 28,519 middle and high school students selected with multistage clustered sampling in the Mexican National Survey of Student's Drug Use. Using a self-administered questionnaire, lifetime suicidal attempt and four indicators of academic performance were assessed: age inconsistency with grade level, not being a student in the last year, perceived academic performance and number of failed courses. Multiple logistic regression models were used to control for sociodemographic and school characteristics. The lifetime prevalence of attempted suicide was 3.0% for middle school students and 4.2% for high school students. Among middle school students, statistically adjusted significant associations of suicide attempt with academic performance indicators were: not being a student the year before, worse self-perceived performance and a higher number of failed courses; among high school students, predictors were failed courses and self-perceived academic performance, with ORs of 1.65 and 1.96 for the categories of good and fair/poor respectively, compared to those who reported very good performance. Self-perceived academic performance was the main indicator for suicide in both school levels. Suicide prevention efforts in Mexico's schools should include asking students about the perception they have about their own academic performance.

Mediating influences of social support on stress at Three Mile Island.

PubMed

Fleming, R; Baum, A; Gisriel, M M; Gatchel, R J

1982-09-01

Symptom reporting, task performance, and urinary catecholamine excretion were studied in a group of people living near the Three Mile Island nuclear power plant and in control populations. More than a year after the accident, living near the damaged reactor was associated with elevations in all indices of stress compared with control levels. Social support mediated these stress indices such that higher levels were associated with fewer psychological and behavioral symptoms of stress. Biochemical measures showed a different pattern of results.

Neotectonic control on drainage systems: GIS-based geomorphometric and morphotectonic assessment for Crete, Greece

NASA Astrophysics Data System (ADS)

Argyriou, Athanasios V.; Teeuw, Richard M.; Soupios, Pantelis; Sarris, Apostolos

2017-11-01

Geomorphic indices can be used to examine the geomorphological and tectonic processes responsible for the development of the drainage basins. Such indices can be dependent on tectonics, erosional processes and other factors that control the morphology of the landforms. The inter-relationships between geomorphic indices can determine the influence of regional tectonic activity in the shape development of drainage basins. A Multi-Criteria Decision Analysis (MCDA) procedure has been used to perform an integrated cluster analysis that highlights information associated with the dominant regional tectonic activity. Factor Analysis (FA) and Analytical Hierarchy Process (AHP) were considered within that procedure, producing a representation of the distributed regional tectonic activity of the drainage basins studied. The study area is western Crete, located in the outer fore-arc of the Hellenic subduction zone, one of the world's most tectonically active regions. The results indicate that in the landscape evolution of the study area (especially the western basins) tectonic controls dominate over lithological controls.

Locomotor sensory organization test: a novel paradigm for the assessment of sensory contributions in gait.

PubMed

Chien, Jung Hung; Eikema, Diderik-Jan Anthony; Mukherjee, Mukul; Stergiou, Nicholas

2014-12-01

Feedback based balance control requires the integration of visual, proprioceptive and vestibular input to detect the body's movement within the environment. When the accuracy of sensory signals is compromised, the system reorganizes the relative contributions through a process of sensory recalibration, for upright postural stability to be maintained. Whereas this process has been studied extensively in standing using the Sensory Organization Test (SOT), less is known about these processes in more dynamic tasks such as locomotion. In the present study, ten healthy young adults performed the six conditions of the traditional SOT to quantify standing postural control when exposed to sensory conflict. The same subjects performed these six conditions using a novel experimental paradigm, the Locomotor SOT (LSOT), to study dynamic postural control during walking under similar types of sensory conflict. To quantify postural control during walking, the net Center of Pressure sway variability was used. This corresponds to the Performance Index of the center of pressure trajectory, which is used to quantify postural control during standing. Our results indicate that dynamic balance control during locomotion in healthy individuals is affected by the systematic manipulation of multisensory inputs. The sway variability patterns observed during locomotion reflect similar balance performance with standing posture, indicating that similar feedback processes may be involved. However, the contribution of visual input is significantly increased during locomotion, compared to standing in similar sensory conflict conditions. The increased visual gain in the LSOT conditions reflects the importance of visual input for the control of locomotion. Since balance perturbations tend to occur in dynamic tasks and in response to environmental constraints not present during the SOT, the LSOT may provide additional information for clinical evaluation on healthy and deficient sensory processing.

Preliminary Effect of Synthetic Vision Systems Displays to Reduce Low-Visibility Loss of Control and Controlled Flight Into Terrain Accidents

NASA Technical Reports Server (NTRS)

Glaab, Louis J.; Takallu, Mohammad A.

2002-01-01

An experimental investigation was conducted to study the effectiveness of Synthetic Vision Systems (SVS) flight displays as a means of eliminating Low Visibility Loss of Control (LVLOC) and Controlled Flight Into Terrain (CFIT) accidents by low time general aviation (GA) pilots. A series of basic maneuvers were performed by 18 subject pilots during transition from Visual Meteorological Conditions (VMC) to Instrument Meteorological Conditions (IMC), with continued flight into IMC, employing a fixed-based flight simulator. A total of three display concepts were employed for this evaluation. One display concept, referred to as the Attitude Indicator (AI) replicated instrumentation common in today's General Aviation (GA) aircraft. The second display concept, referred to as the Electronic Attitude Indicator (EAI), featured an enlarged attitude indicator that was more representative of a glass display that also included advanced flight symbology, such as a velocity vector. The third concept, referred to as the SVS display, was identical to the EAI except that computer-generated terrain imagery replaced the conventional blue-sky/brown-ground of the EAI. Pilot performance parameters, pilot control inputs and physiological data were recorded for post-test analysis. Situation awareness (SA) and qualitative pilot comments were obtained through questionnaires and free-form interviews administered immediately after the experimental session. Initial pilot performance data were obtained by instructor pilot observations. Physiological data (skin temperature, heart rate, and muscle flexure) were also recorded. Preliminary results indicate that far less errors were committed when using the EAI and SVS displays than when using conventional instruments. The specific data example examined in this report illustrates the benefit from SVS displays to avoid massive loss of SA conditions. All pilots acknowledged the enhanced situation awareness provided by the SVS display concept. Levels of pilot stress appear to be correlated with skin temperature measurements.

34 CFR 361.89 - Enforcement procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... revisions until the DSU sustains satisfactory performance based on the current performance levels over a period of more than 1 year. (d) If the Secretary determines that a DSU with less than satisfactory... satisfactory level on the compliance indicators. (Approved by the Office of Management and Budget under control...

78 FR 48726 - Placement of the Georgia Agreement State Program on Probation

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-09

... the Integrated Materials Performance Evaluation Program (IMPEP). The Management Review Board (MRB), in... CONTACT: Lisa Dimmick, Office of Federal and State Materials and Environmental Management Programs, U.S... Agreement State radiation control programs, using performance indicators, to ensure that public health and...

Exposure reduces negative bias in self-rated performance in public speaking fearful participants.

PubMed

Cheng, Joyce; Niles, Andrea N; Craske, Michelle G

2017-03-01

Individuals with public speaking anxiety (PSA) under-rate their performance compared to objective observers. The present study examined whether exposure reduces the discrepancy between self and observer performance ratings and improved observer-rated performance in individuals with PSA. PSA participants gave a speech in front of a small audience and rated their performance using a questionnaire before and after completing repeated exposures to public speaking. Non-anxious control participants gave a speech and completed the questionnaire one time only. Objective observers watched videos of the speeches and rated performance using the same questionnaire. PSA participants underrated their performance to a greater degree than did controls prior to exposure, but also performed significantly more poorly than did controls when rated objectively. Bias significantly decreased and objective-rated performance significantly increased following completion of exposure in PSA participants, and on one performance measure, anxious participants no longer showed a greater discrepancy between self and observer performance ratings compared to controls. The study employed non-clinical student sample, but the results should be replicated in clinical anxiety samples. These findings indicate that exposure alone significantly reduces negative performance bias among PSA individuals, but additional exposure or additional interventions may be necessary to fully correct bias and performance deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

Servo Controlled Variable Pressure Modification to Space Shuttle Hydraulic Pump

NASA Technical Reports Server (NTRS)

Kouns, H. H.

1983-01-01

Engineering drawings show modifications made to the constant pressure control of the model AP27V-7 hydraulic pump to an electrically controlled variable pressure setting compensator. A hanger position indicator was included for continuously monitoring hanger angle. A simplex servo driver was furnished for controlling the pressure setting servovalve. Calibration of the rotary variable displacement transducer is described as well as pump performance and response characteristics.

ETR CONTROL BUILDING, TRA647, INTERIOR. CONTROL ROOM, CONTEXTUAL VIEW. INSTRUMENT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR CONTROL BUILDING, TRA-647, INTERIOR. CONTROL ROOM, CONTEXTUAL VIEW. INSTRUMENT PANELS AT REAR OF OPERATOR'S CONSOLE GAVE OPERATOR STATUS OF REACTOR PERFORMANCE, COOLANT-WATER CHARACTERISTICS AND OTHER INDICATORS. WINDOWS AT RIGHT LOOKED INTO ETR BUILDING FIRST FLOOR. CAMERA FACING EAST. INL NEGATIVE NO. HD42-6. Mike Crane, Photographer, 3/2004 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Behavioral and Neural Inhibitory Control Moderates the Effects of Reward Sensitivity on Adolescent Substance Use

PubMed Central

Kim-Spoon, Jungmeen; Deater-Deckard, Kirby; Holmes, Christopher; Lee, Jacob; Chiu, Pearl; King-Casas, Brooks

2016-01-01

The developmental period of adolescence is characterized by increasing incidence of health risk behaviors, including experimenting with drugs and alcohol. We examined how inhibitory control interacts with reward and punishment sensitivity to predict substance use severity and age of onset among early adolescents. The sample was comprised of 157 early adolescents (13-14 years of age, 52% male). Composite scores for behavioral activation system (BAS), behavioral inhibition system (BIS), and substance use severity and onset were computed using adolescents’ questionnaire data, and inhibitory control was assessed based on adolescents’ behavioral performance and brain imaging during the Multiple Source Interference Task (MSIT). Structural equation modeling analyses indicated that for both behavioral performance and neural activity indicators of inhibitory control, high levels of BAS predicted earlier onset of substance use among adolescents with low inhibitory control—but not among adolescents with high inhibitory control. BIS was not related to substance use severity and onset among adolescents. The results support the theoretically hypothesized moderating role of inhibitory control and its associated frontal cortex functioning, and offer new insights into the identification of adolescents with neurobehavioral vulnerabilities to developing maladaptive substance use behaviors. PMID:27580969

Cognitive Control Acts Locally

ERIC Educational Resources Information Center

Notebaert, Wim; Verguts, Tom

2008-01-01

Cognitive control adjusts information processing to momentary needs and task requirements. We investigated conflict adaptation when participants are performing two tasks, a Simon task and a SNARC task. The results indicated that one congruency effect (e.g., Simon) was reduced after conflict in the other task (e.g., SNARC), but only when both tasks…

Problems in air traffic management. V., Identification and potential aptitude test measures for selection of tower air traffic controller trainees.

DOT National Transportation Integrated Search

1965-07-01

A study of over 200 Terminal Air Traffic Control Specialists indicated that their training performance could be well predicted by a composite of four aptitude tests measuring: numerical ability, non-verbal abstract reasoning, ability to solve simplif...

The Association between Mild Traumatic Brain Injury History and Cognitive Control

ERIC Educational Resources Information Center

Pontifex, Matthew B.; O'Connor, Phillip M.; Broglio, Steven P.; Hillman, Charles H.

2009-01-01

The influence of multiple mild traumatic brain injuries (mTBIs) on neuroelectric and task performance indices of the cognitive control of action monitoring was assessed in individuals with and without a history of concussion. Participants completed a standard clinical neurocognitive assessment and the error-related negativity of the…

Locus of Control and Performance: Widening Applicabilities

ERIC Educational Resources Information Center

Manichander, T.

2014-01-01

In an attempt to explain the evidence which indicates that internal perception of control is positively related to academic achievement, this paper suggests that mediating motivational and cognitive reactions, which differentiate internals from externals, may account for this relationship. Furthermore, on the basis of data which suggest that the…

Verification test results of Apollo stabilization and control systems during undocked operations

NASA Technical Reports Server (NTRS)

Copeland, E. L.; Haken, R. L.

1974-01-01

The results are presented of analysis and simulation testing of both the Skylark 1 reaction control system digital autopilot (RCS DAP) and the thrust vector control (TVC) autopilot for use during the undocked portions of the Apollo/Soyuz Test Project Mission. The RCS DAP testing was performed using the Skylab Functional Simulator (SLFS), a digital computer program capable of simulating the Apollo and Skylab autopilots along with vehicle dynamics including bending and sloshing. The model is used to simulate three-axis automatic maneuvers along with pilot controlled manual maneuvers using the RCS DAP. The TVC autopilot was tested in two parts. A classical stability analysis was performed on the vehicle considering the effects of structural bending and sloshing when under control of the TVC autopilot. The time response of the TVC autopilot was tested using the SLFS. Results indicate that adequate performance stability margins can be expected for the CSM/DM configuration when under the control of the Apollo control systems tested.

Modelling the influence of sensory dynamics on linear and nonlinear driver steering control

NASA Astrophysics Data System (ADS)

Nash, C. J.; Cole, D. J.

2018-05-01

A recent review of the literature has indicated that sensory dynamics play an important role in the driver-vehicle steering task, motivating the design of a new driver model incorporating human sensory systems. This paper presents a full derivation of the linear driver model developed in previous work, and extends the model to control a vehicle with nonlinear tyres. Various nonlinear controllers and state estimators are compared with different approximations of the true system dynamics. The model simulation time is found to increase significantly with the complexity of the controller and state estimator. In general the more complex controllers perform best, although with certain vehicle and tyre models linearised controllers perform as well as a full nonlinear optimisation. Various extended Kalman filters give similar results, although the driver's sensory dynamics reduce control performance compared with full state feedback. The new model could be used to design vehicle systems which interact more naturally and safely with a human driver.

Extraneous torque and compensation control on the electric load simulator

NASA Astrophysics Data System (ADS)

Jiao, Zongxia; Li, Chenggong; Ren, Zhiting

2003-09-01

In this paper a novel motor-drive load simulator based on compensation control strategy is proposed and designed. Through analyzing the torque control system consisting of DC torque motor, PWM module and torque sensor, it is shown that performance of the motor-drive load simulator is possible to be as good as that of the electro-hydraulic load simulator in the range of small torque. In the course of loading, the rotation of the actuator would cause a strong disturbance torque through the motor back-EMF, which produces extraneous torque similar as in electro-hydraulic load simulator. This paper analyzes the cause of extraneous torque inside the torque motor in detail and presents an appropriate compensation control with which the extraneous torque can be compensated and the good performance of the torque control system can be obtained. The results of simulation indicate that the compensation is very effective and the track performance is according with the request.

Design of an adaptive super-twisting decoupled terminal sliding mode control scheme for a class of fourth-order systems.

PubMed

Ashtiani Haghighi, Donya; Mobayen, Saleh

2018-04-01

This paper proposes an adaptive super-twisting decoupled terminal sliding mode control technique for a class of fourth-order systems. The adaptive-tuning law eliminates the requirement of the knowledge about the upper bounds of external perturbations. Using the proposed control procedure, the state variables of cart-pole system are converged to decoupled terminal sliding surfaces and their equilibrium points in the finite time. Moreover, via the super-twisting algorithm, the chattering phenomenon is avoided without affecting the control performance. The numerical results demonstrate the high stabilization accuracy and lower performance indices values of the suggested method over the other ones. The simulation results on the cart-pole system as well as experimental validations demonstrate that the proposed control technique exhibits a reasonable performance in comparison with the other methods. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Combining performance and outcome indicators can be used in a standardized way: a pilot study of two multidisciplinary, full-scale major aircraft exercises

PubMed Central

2012-01-01

Background Disaster medicine is a fairly young scientific discipline and there is a need for the development of new methods for evaluation and research. This includes full-scale disaster exercisers. A standardized concept on how to evaluate these exercises, could lead to easier identification of pitfalls caused by system-errors in the organization. The aim of this study was to demonstrate the feasibility of using a combination of performance and outcome indicators so that results can be compared in standardized full-scale exercises. Methods Two multidisciplinary, full-scale exercises were studied in 2008 and 2010. The panorama had the same setup. Sets of performance indicators combined with indicators for unfavorable patient outcome were recorded in predesigned templates. Evaluators, all trained in a standardized way at a national disaster medicine centre, scored the results on predetermined locations; at the scene, at hospital and at the regional command and control. Results All data regarding the performance indicators of the participants during the exercises were obtained as well as all data regarding indicators for patient outcome. Both exercises could therefore be compared regarding performance (processes) as well as outcome indicators. The data from the performance indicators during the exercises showed higher scores for the prehospital command in the second exercise 15 points and 3 points respectively. Results from the outcome indicators, patient survival and patient complications, demonstrated a higher number of preventable deaths and a lower number of preventable complications in the exercise 2010. In the exercise 2008 the number of preventable deaths was lower and the number of preventable complications was higher. Conclusions Standardized multidisciplinary, full-scale exercises in different settings can be conducted and evaluated with performance indicators combined with outcome indicators enabling results from exercises to be compared. If exercises are performed in a standardized way, results may serve as a basis for lessons learned. Future use of the same concept using the combination of performance indicators and patient outcome indicators may demonstrate new and important evidence that could lead to new and better knowledge that also may be applied during real incidents. PMID:22929479

Combining performance and outcome indicators can be used in a standardized way: a pilot study of two multidisciplinary, full-scale major aircraft exercises.

PubMed

Rådestad, Monica; Nilsson, Heléne; Castrén, Maaret; Svensson, Leif; Rüter, Anders; Gryth, Dan

2012-08-28

Disaster medicine is a fairly young scientific discipline and there is a need for the development of new methods for evaluation and research. This includes full-scale disaster exercisers. A standardized concept on how to evaluate these exercises, could lead to easier identification of pitfalls caused by system-errors in the organization. The aim of this study was to demonstrate the feasibility of using a combination of performance and outcome indicators so that results can be compared in standardized full-scale exercises. Two multidisciplinary, full-scale exercises were studied in 2008 and 2010. The panorama had the same setup. Sets of performance indicators combined with indicators for unfavorable patient outcome were recorded in predesigned templates. Evaluators, all trained in a standardized way at a national disaster medicine centre, scored the results on predetermined locations; at the scene, at hospital and at the regional command and control. All data regarding the performance indicators of the participants during the exercises were obtained as well as all data regarding indicators for patient outcome. Both exercises could therefore be compared regarding performance (processes) as well as outcome indicators. The data from the performance indicators during the exercises showed higher scores for the prehospital command in the second exercise 15 points and 3 points respectively. Results from the outcome indicators, patient survival and patient complications, demonstrated a higher number of preventable deaths and a lower number of preventable complications in the exercise 2010. In the exercise 2008 the number of preventable deaths was lower and the number of preventable complications was higher. Standardized multidisciplinary, full-scale exercises in different settings can be conducted and evaluated with performance indicators combined with outcome indicators enabling results from exercises to be compared. If exercises are performed in a standardized way, results may serve as a basis for lessons learned. Future use of the same concept using the combination of performance indicators and patient outcome indicators may demonstrate new and important evidence that could lead to new and better knowledge that also may be applied during real incidents.

The Impact of Pictorial Display on Operator Learning and Performance. M.S. Thesis

NASA Technical Reports Server (NTRS)

Miller, R. A.; Messing, L. J.; Jagacinski, R. J.

1984-01-01

The effects of pictorially displayed information on human learning and performance of a simple control task were investigated. The controlled system was a harmonic oscillator and the system response was displayed to subjects as either an animated pendulum or a horizontally moving dot. Results indicated that the pendulum display did not effect performance scores but did significantly effect the learning processes of individual operators. The subjects with the pendulum display demonstrated more vertical internal models early in the experiment and the manner in which their internal models were tuned with practice showed increased variability between subjects.

Experimental investigation of control/display augmentation effects in a compensatory tracking task

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Schmidt, David K.

1988-01-01

The effects of control/display augmentation on human performance and workload have been investigated for closed-loop, continuous-tracking tasks by a real-time, man-in-the-loop simulation study. The experimental results obtained indicate that only limited improvement in actual tracking performance is obtainable through display augmentation alone; with a very high level of display augmentation, tracking error will actually deteriorate. Tracking performance improves when status information is furnished for reasonable levels of display quickening; again, very high quickening levels lead to tracking error deterioration due to the incompatibility between the status information and the quickened signal.

Short progressive muscle relaxation or motor coordination training does not increase performance in a brain-computer interface based on sensorimotor rhythms (SMR).

PubMed

Botrel, L; Acqualagna, L; Blankertz, B; Kübler, A

2017-11-01

Brain computer interfaces (BCIs) allow for controlling devices through modulation of sensorimotor rhythms (SMR), yet a profound number of users is unable to achieve sufficient accuracy. Here, we investigated if visuo-motor coordination (VMC) training or Jacobsen's progressive muscle relaxation (PMR) prior to BCI use would increase later performance compared to a control group who performed a reading task (CG). Running the study in two different BCI-labs, we achieved a joint sample size of N=154 naïve participants. No significant effect of either intervention (VMC, PMR, control) was found on resulting BCI performance. Relaxation level and visuo-motor performance were associated with later BCI performance in one BCI-lab but not in the other. These mixed results do not indicate a strong potential of VMC or PMR for boosting performance. Yet further research with different training parameters or experimental designs is needed to complete the picture. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of Teaching a Conceptual Hierarchy on Concept Classification Performance.

ERIC Educational Resources Information Center

Wilcox, Wayne C.; And Others

1981-01-01

In the research study described, 80 subjects in one control and four treatment groups viewed sets of slides on types of sailboats. Results indicate that making apparent the hierarchical relationships among concepts of a conceptual hierarchy enhances learner performance in classifying unencountered instances of those concepts. Thirty-eight…

A Performance of Individual Differences in Selective Attention.

ERIC Educational Resources Information Center

Wahl, Otto

A reliable, easily administered performance test of selective attentional ability was sought. A monaural listening task provided a baseline control for adequate hearing and memory; a dichotic listening task then provided indices of ability to focus attention and resist distraction while a simultaneous listening task provided measures of ability to…

Memory-focused interventions for people with cognitive disorders: A systematic review and meta-analysis of randomized controlled studies.

PubMed

Yang, Hui-Ling; Chan, Pi-Tuan; Chang, Pi-Chen; Chiu, Huei-Ling; Sheen Hsiao, Shu-Tai; Chu, Hsin; Chou, Kuei-Ru

2018-02-01

A better understanding of people with cognitive disorders improves performance on memory tasks through memory-focused interventions are needed. The purpose of this study was to assess the effect of memoryfocused interventions on cognitive disorders through a meta-analysis. Systematic review and meta-analysis. The online electronic databases PubMed, the Cochrane Library, Ovid-Medline, CINHAL, PsycINFO, Ageline, and Embase (up to May 2017) were used in this study. No language restriction was applied to the search. Objective memory (learning and memory function, immediate recall, delayed recall, and recognition) was the primary indicator and subjective memory performance, global cognitive function, and depression were the secondary indicators. The Hedges' g of change, subgroup analyses, and meta-regression were analyzed on the basis of the characteristics of people with cognitive disorders. A total of 27 studies (2177 participants, mean age=75.80) reporting RCTs were included in the meta-analysis. The results indicated a medium-to-large effect of memory-focused interventions on learning and memory function (Hedges' g=0.62) and subjective memory performance (Hedges' g=0.67), a small-to-medium effect on delayed recall and depression, and a small effect on immediate recall and global cognitive function (all p<0.05) compared with the control. Subgroup analysis and meta-regression indicated that the effects on learning and memory function were more profound in the format of memory training, individual training, shorter treatment duration, and more than eight treatment sessions, and the effect size indicated the MMSE score was the most crucial indicator (β=-0.06, p=0.04). This is first comprehensive meta-analysis of special memory domains in people with cognitive disorders. The results revealed that memory-focused interventions effectively improved memory-related performance in people with cognitive disorders. An appropriately designed intervention can effectively improve memory function, reduce disability progression, and improve mood state in people with cognitive disorders. Additional randomized controlled trials including measures of recognition, global cognitive function, and depression should be conducted and analyzed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of display and control concepts for a terminal configured vehicle in final approach in a windshear environment

NASA Technical Reports Server (NTRS)

Levison, W. H.

1978-01-01

A revised treatment of nonrandom inputs was incorporated in the model. Response behavior was observed for two display configurations (a pictorial EADI presentation and a flight-director configuration requiring use of a panel-mounted airspeed indicator), two control configurations (attitude and velocity control wheel steering), and two shear environments, each of which contained a head-to-tail shear and a vertical component. In general, performance trends predicted by the model were confirmed experimentally. Experimental and analytical results both indicated superiority to the EADI display with respect to regulation of height and airspeed errors. Velocity steering allowed tighter regulation of height errors, but control parameters had little influence on airspeed regulation. Model analysis indicated that display-related differences could be ascribed to differences in the quality of speed-related information provided by the two displays.

Comparative study between two different active flutter suppression systems

NASA Technical Reports Server (NTRS)

Nissim, E.

1978-01-01

An activated leading-edge (LE)-tailing-edge (TE) control system is applied to a drone aircraft with the objective of enabling the drone to fly subsonically at dynamic pressures which are 44% above the open-loop flutter dynamic pressure. The control synthesis approach is based on the aerodynamic energy concept and it incorporates recent developments in this area. A comparison is made between the performance of the activated LE-TE control system and the performance of a TE control system, analyzed in a previous work. The results obtained indicate that although all the control systems achieve the flutter suppression objectives, the TE control system appears to be somewhat superior to the LE-TE control system, in this specific application. This superiority is manifested through reduced values of control surface activity over a wide range of flight conditions.

Optimized PID control of depth of hypnosis in anesthesia.

PubMed

Padula, Fabrizio; Ionescu, Clara; Latronico, Nicola; Paltenghi, Massimiliano; Visioli, Antonio; Vivacqua, Giulio

2017-06-01

This paper addresses the use of proportional-integral-derivative controllers for regulating the depth of hypnosis in anesthesia by using propofol administration and the bispectral index as a controlled variable. In fact, introducing an automatic control system might provide significant benefits for the patient in reducing the risk for under- and over-dosing. In this study, the controller parameters are obtained through genetic algorithms by solving a min-max optimization problem. A set of 12 patient models representative of a large population variance is used to test controller robustness. The worst-case performance in the considered population is minimized considering two different scenarios: the induction case and the maintenance case. Our results indicate that including a gain scheduling strategy enables optimal performance for induction and maintenance phases, separately. Using a single tuning to address both tasks may results in a loss of performance up to 102% in the induction phase and up to 31% in the maintenance phase. Further on, it is shown that a suitably designed low-pass filter on the controller output can handle the trade-off between the performance and the noise effect in the control variable. Optimally tuned PID controllers provide a fast induction time with an acceptable overshoot and a satisfactory disturbance rejection performance during maintenance. These features make them a very good tool for comparison when other control algorithms are developed. Copyright © 2017 Elsevier B.V. All rights reserved.

Metacognitive monitoring and control in visual change detection: Implications for situation awareness and cognitive control

PubMed Central

McAnally, Ken I.; Morris, Adam P.; Best, Christopher

2017-01-01

Metacognitive monitoring and control of situation awareness (SA) are important for a range of safety-critical roles (e.g., air traffic control, military command and control). We examined the factors affecting these processes using a visual change detection task that included representative tactical displays. SA was assessed by asking novice observers to detect changes to a tactical display. Metacognitive monitoring was assessed by asking observers to estimate the probability that they would correctly detect a change, either after study of the display and before the change (judgement of learning; JOL) or after the change and detection response (judgement of performance; JOP). In Experiment 1, observers failed to detect some changes to the display, indicating imperfect SA, but JOPs were reasonably well calibrated to objective performance. Experiment 2 examined JOLs and JOPs in two task contexts: with study-time limits imposed by the task or with self-pacing to meet specified performance targets. JOPs were well calibrated in both conditions as were JOLs for high performance targets. In summary, observers had limited SA, but good insight about their performance and learning for high performance targets and allocated study time appropriately. PMID:28915244

Sensitivity of Space Station alpha joint robust controller to structural modal parameter variations

NASA Technical Reports Server (NTRS)

Kumar, Renjith R.; Cooper, Paul A.; Lim, Tae W.

1991-01-01

The photovoltaic array sun tracking control system of Space Station Freedom is described. A synthesis procedure for determining optimized values of the design variables of the control system is developed using a constrained optimization technique. The synthesis is performed to provide a given level of stability margin, to achieve the most responsive tracking performance, and to meet other design requirements. Performance of the baseline design, which is synthesized using predicted structural characteristics, is discussed and the sensitivity of the stability margin is examined for variations of the frequencies, mode shapes and damping ratios of dominant structural modes. The design provides enough robustness to tolerate a sizeable error in the predicted modal parameters. A study was made of the sensitivity of performance indicators as the modal parameters of the dominant modes vary. The design variables are resynthesized for varying modal parameters in order to achieve the most responsive tracking performance while satisfying the design requirements. This procedure of reoptimization design parameters would be useful in improving the control system performance if accurate model data are provided.

Control Law for Automatic Landing Using Fuzzy-Logic Control

NASA Astrophysics Data System (ADS)

Kato, Akio; Inagaki, Yoshiki

The effectiveness of a fuzzy-logic control law for automatically landing an aircraft that handles both the control to lead an aircraft from horizontal flight at an altitude of 500 meters to flight along the glide-path course near the runway, as well as the control to direct the aircraft to land smoothly on a runway, was investigated. The control law for the automatic landing was designed to match the design goals of directing an aircraft from horizontal flight to flight along a glide-path course quickly and smoothly, and for landing smoothly on a runway. The design of the control law and evaluation of the control performance were performed considering the ground effect at landing. As a result, it was confirmed that the design goals were achieved. Even if the characteristics of the aircraft change greatly, the proposed control law is able to maintain the control performance. Moreover, it was confirmed to be able to land an aircraft safely during air turbulence. The present paper indicates that fuzzy-logic control is an effective and flexible method when applied to the control law for automatic landing, and the design method of the control law using fuzzy-logic control was obtained.

Load Index Metrics for an Optimized Management of Web Services: A Systematic Evaluation

PubMed Central

Souza, Paulo S. L.; Santana, Regina H. C.; Santana, Marcos J.; Zaluska, Ed; Faical, Bruno S.; Estrella, Julio C.

2013-01-01

The lack of precision to predict service performance through load indices may lead to wrong decisions regarding the use of web services, compromising service performance and raising platform cost unnecessarily. This paper presents experimental studies to qualify the behaviour of load indices in the web service context. The experiments consider three services that generate controlled and significant server demands, four levels of workload for each service and six distinct execution scenarios. The evaluation considers three relevant perspectives: the capability for representing recent workloads, the capability for predicting near-future performance and finally stability. Eight different load indices were analysed, including the JMX Average Time index (proposed in this paper) specifically designed to address the limitations of the other indices. A systematic approach is applied to evaluate the different load indices, considering a multiple linear regression model based on the stepwise-AIC method. The results show that the load indices studied represent the workload to some extent; however, in contrast to expectations, most of them do not exhibit a coherent correlation with service performance and this can result in stability problems. The JMX Average Time index is an exception, showing a stable behaviour which is tightly-coupled to the service runtime for all executions. Load indices are used to predict the service runtime and therefore their inappropriate use can lead to decisions that will impact negatively on both service performance and execution cost. PMID:23874776

Independent Orbiter Assessment (IOA): Analysis of the displays and controls subsystem

NASA Technical Reports Server (NTRS)

Trahan, W. H.; Prust, E. E.

1987-01-01

The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Displays and Controls (D and C) subsystem hardware. The function of the D and C hardware is to provide the crew with the monitor, command, and control capabilities required for management of all normal and contingency mission and flight operations. The D and C hardware for which failure modes analysis was performed consists of the following: Acceleration Indicator (G-METER); Head Up Display (HUD); Display Driver Unit (DDU); Alpha/Mach Indicator (AMI); Horizontal Situation Indicator (HSI); Attitude Director Indicator (ADI); Propellant Quantity Indicator (PQI); Surface Position Indicator (SPI); Altitude/Vertical Velocity Indicator (AVVI); Caution and Warning Assembly (CWA); Annunciator Control Assembly (ACA); Event Timer (ET); Mission Timer (MT); Interior Lighting; and Exterior Lighting. Each hardware item was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.

Creativity on tap? Effects of alcohol intoxication on creative cognition.

PubMed

Benedek, Mathias; Panzierer, Lisa; Jauk, Emanuel; Neubauer, Aljoscha C

2017-11-01

Anecdotal reports link alcohol intoxication to creativity, while cognitive research highlights the crucial role of cognitive control for creative thought. This study examined the effects of mild alcohol intoxication on creative cognition in a placebo-controlled design. Participants completed executive and creative cognition tasks before and after consuming either alcoholic beer (BAC of 0.03) or non-alcoholic beer (placebo). Alcohol impaired executive control, but improved performance in the Remote Associates Test, and did not affect divergent thinking ability. The findings indicate that certain aspects of creative cognition benefit from mild attenuations of cognitive control, and contribute to the growing evidence that higher cognitive control is not always associated with better cognitive performance. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Health, safety and environmental unit performance assessment model under uncertainty (case study: steel industry).

PubMed

Shamaii, Azin; Omidvari, Manouchehr; Lotfi, Farhad Hosseinzadeh

2017-01-01

Performance assessment is a critical objective of management systems. As a result of the non-deterministic and qualitative nature of performance indicators, assessments are likely to be influenced by evaluators' personal judgments. Furthermore, in developing countries, performance assessments by the Health, Safety and Environment (HSE) department are based solely on the number of accidents. A questionnaire is used to conduct the study in one of the largest steel production companies in Iran. With respect to health, safety, and environment, the results revealed that control of disease, fire hazards, and air pollution are of paramount importance, with coefficients of 0.057, 0.062, and 0.054, respectively. Furthermore, health and environment indicators were found to be the most common causes of poor performance. Finally, it was shown that HSE management systems can affect the majority of performance safety indicators in the short run, whereas health and environment indicators require longer periods of time. The objective of this study is to present an HSE-MS unit performance assessment model in steel industries. Moreover, we seek to answer the following question: what are the factors that affect HSE unit system in the steel industry? Also, for each factor, the extent of impact on the performance of the HSE management system in the organization is determined.

Stroop proactive control and task conflict are modulated by concurrent working memory load.

PubMed

Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai; Davelaar, Eddy J; Usher, Marius

2015-06-01

Performance on the Stroop task reflects two types of conflict-informational (between the incongruent word and font color) and task (between the contextually relevant color-naming task and the irrelevant, but automatic, word-reading task). According to the dual mechanisms of control theory (DMC; Braver, 2012), variability in Stroop performance can result from variability in the deployment of a proactive task-demand control mechanism. Previous research has shown that when proactive control (PC) is diminished, both increased Stroop interference and a reversed Stroop facilitation (RF) are observed. Although the current DMC model accounts for the former effect, it does not predict the observed RF, which is considered to be behavioral evidence for task conflict in the Stroop task. Here we expanded the DMC model to account for Stroop RF. Assuming that a concurrent working memory (WM) task reduces PC, we predicted both increased interference and an RF. Nineteen participants performed a standard Stroop task combined with a concurrent n-back task, which was aimed at reducing available WM resources, and thus overloading PC. Although the results indicated common Stroop interference and facilitation in the low-load condition (zero-back), in the high-load condition (two-back), both increased Stroop interference and RF were observed, consistent with the model's prediction. These findings indicate that PC is modulated by concurrent WM load and serves as a common control mechanism for both informational and task Stroop conflicts.

The effect of learning climate on snack consumption and ego depletion among undergraduate students.

PubMed

Magaraggia, Christian; Dimmock, James A; Jackson, Ben

2013-10-01

We explored the effect of controlled and autonomous learning choices on the consumption of a high-energy snack food, and also examined whether snack consumption during a controlled choice learning activity could 'up-regulate' subsequent performance on a self-regulation task. Participants were randomly assigned to a controlled choice learning condition in which food was provided, a controlled choice learning condition in which food was not provided, or an autonomous choice learning condition in which food was provided. Results indicated that the autonomous choice group consumed significantly less snack food than the controlled-choice-and-food group. Participants in the autonomous choice condition also performed better on the subsequent self-regulation task than the controlled-choice-and-food group, even after controlling for the amount of food consumed. Furthermore, within the controlled-choice-and-food condition, there was no association between food consumption and subsequent self-regulation task performance. Discussion focuses on the potential impact of a controlled learning climate on snack food consumption and on the degradation of self-regulation capacities. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

A program to evaluate a control system based on feedback of aerodynamic pressure differentials

NASA Technical Reports Server (NTRS)

Levy, D. W.; Finn, P.; Roskam, J.

1981-01-01

The use of aerodynamic pressure differentials to position a control surface is evaluated. The system is a differential pressure command loop, analogous to a position command loop, where the surface is commanded to move until a desired differential pressure across the surface is achieved. This type of control is more direct and accurate because it is the differential pressure which causes the control forces and moments. A frequency response test was performed in a low speed wind tunnel to measure the performance of the system. Both pressure and position feedback were tested. The pressure feedback performed as well as position feedback implying that the actuator, with a break frequency on the order of 10 Rad/sec, was the limiting component. Theoretical considerations indicate that aerodynamic lags will not appear below frequencies of 50 Rad/sec, or higher.

Metacognition of agency is reduced in high hypnotic suggestibility.

PubMed

Terhune, Devin B; Hedman, Love R A

2017-11-01

A disruption in the sense of agency is the primary phenomenological feature of response to hypnotic suggestions but its cognitive basis remains elusive. Here we tested the proposal that distorted volition during response to suggestions arises from poor metacognition pertaining to the sources of one's control. Highly suggestible and control participants completed a motor task in which performance was reduced through surreptitious manipulations of cursor lag and stimuli speed. Highly suggestible participants did not differ from controls in performance or metacognition of performance, but their sense of agency was less sensitive to cursor lag manipulations, suggesting reduced awareness that their control was being manipulated. These results indicate that highly suggestible individuals have aberrant metacognition of agency and may be a valuable population for studying distortions in the sense of agency. Copyright © 2017 Elsevier B.V. All rights reserved.

Visual imaging capacity and imagery control in Fine Arts students.

PubMed

Pérez-Fabello, Maria José; Campos, Alfredo; Gómez-Juncal, Rocío

2007-06-01

This study investigated relationships between visual imaging abilities (imaging capacity and imagery control) and academic performance in 146 Fine Arts students (31 men, 115 women). Mean age was 22.3 yr. (SD= 1.9; range 20-26 yr.). All of the participants who volunteered for the experiment regularly attended classes and were first, second, or third year students. For evaluation of imaging abilities, the Spanish versions of the Gordon Test of Visual Imagery Control, the Vividness of Visual Imagery Questionnaire, the Verbalizer-Visualizer Questionnaire, and Betts' Questionnaire Upon Mental Imagery were used. Academic performance was assessed in four areas, Drawing, Painting, Sculpture, and Complementary Subjects, over a three-year period. The results indicate that imagery control was associated with academic performance in Fine Arts. These findings are discussed in the context of previous studies, and new lines of research are proposed.

Integrated Controls-Structures Design Methodology for Flexible Spacecraft

NASA Technical Reports Server (NTRS)

Maghami, P. G.; Joshi, S. M.; Price, D. B.

1995-01-01

This paper proposes an approach for the design of flexible spacecraft, wherein the structural design and the control system design are performed simultaneously. The integrated design problem is posed as an optimization problem in which both the structural parameters and the control system parameters constitute the design variables, which are used to optimize a common objective function, thereby resulting in an optimal overall design. The approach is demonstrated by application to the integrated design of a geostationary platform, and to a ground-based flexible structure experiment. The numerical results obtained indicate that the integrated design approach generally yields spacecraft designs that are substantially superior to the conventional approach, wherein the structural design and control design are performed sequentially.

Identification of Time-Varying Pilot Control Behavior in Multi-Axis Control Tasks

NASA Technical Reports Server (NTRS)

Zaal, Peter M. T.; Sweet, Barbara T.

2012-01-01

Recent developments in fly-by-wire control architectures for rotorcraft have introduced new interest in the identification of time-varying pilot control behavior in multi-axis control tasks. In this paper a maximum likelihood estimation method is used to estimate the parameters of a pilot model with time-dependent sigmoid functions to characterize time-varying human control behavior. An experiment was performed by 9 general aviation pilots who had to perform a simultaneous roll and pitch control task with time-varying aircraft dynamics. In 8 different conditions, the axis containing the time-varying dynamics and the growth factor of the dynamics were varied, allowing for an analysis of the performance of the estimation method when estimating time-dependent parameter functions. In addition, a detailed analysis of pilots adaptation to the time-varying aircraft dynamics in both the roll and pitch axes could be performed. Pilot control behavior in both axes was significantly affected by the time-varying aircraft dynamics in roll and pitch, and by the growth factor. The main effect was found in the axis that contained the time-varying dynamics. However, pilot control behavior also changed over time in the axis not containing the time-varying aircraft dynamics. This indicates that some cross coupling exists in the perception and control processes between the roll and pitch axes.

Mental object rotation in Parkinson's disease.

PubMed

Crucian, Gregory P; Barrett, Anna M; Burks, David W; Riestra, Alonso R; Roth, Heidi L; Schwartz, Ronald L; Triggs, William J; Bowers, Dawn; Friedman, William; Greer, Melvin; Heilman, Kenneth M

2003-11-01

Deficits in visual-spatial ability can be associated with Parkinson's disease (PD), and there are several possible reasons for these deficits. Dysfunction in frontal-striatal and/or frontal-parietal systems, associated with dopamine deficiency, might disrupt cognitive processes either supporting (e.g., working memory) or subserving visual-spatial computations. The goal of this study was to assess visual-spatial orientation ability in individuals with PD using the Mental Rotations Test (MRT), along with other measures of cognitive function. Non-demented men with PD were significantly less accurate on this test than matched control men. In contrast, women with PD performed similarly to matched control women, but both groups of women did not perform much better than chance. Further, mental rotation accuracy in men correlated with their executive skills involving mental processing and psychomotor speed. In women with PD, however, mental rotation accuracy correlated negatively with verbal memory, indicating that higher mental rotation performance was associated with lower ability in verbal memory. These results indicate that PD is associated with visual-spatial orientation deficits in men. Women with PD and control women both performed poorly on the MRT, possibly reflecting a floor effect. Although men and women with PD appear to engage different cognitive processes in this task, the reason for the sex difference remains to be elucidated.

Behaviour planning and problem solving deficiencies in children with symptoms of attention deficit hyperactivity disorder from the Balobedu culture, Limpopo province, South Africa.

PubMed

Pila-Nemutandani, Refilwe Gloria; Meyer, Anneke

2016-07-01

To compare planning behaviour (frontal lobe functioning) in children with and without symptoms of attention deficit hyperactivity disorder (ADHD). A total of 90 children (45 with symptoms of ADHD and 45 matched controls without ADHD symptoms) of both genders, who were medication naïve, from the Balobedu culture (Limpopo province, South Africa), aged 7-13 years, participated in the study. The performance of the two groups was compared on a test of planning and problem solving, the Tower of London (ToL) task. The results were analysed as a function of gender and ADHD subtype. The Finger Tapping test (testing fine motor skills) was used as a control test to verify that the expected differences were not due to poor motor skills. The children with ADHD symptoms scored significantly lower than the non-ADHD comparison group which indicated deficiency in frontal lobe functioning (p = 0.00). The difference in performance was not due to poor motor control (p = 0.70). Children with ADHD symptoms show deficits in behavioural planning which indicates impairment of functions of the frontal areas supplied by the mesocortical dopamine branch. More so than others, the ADHD Inattentive and Combined subtypes showed poor performance in the Tower of London task, indicating poor organisational and planning skills in these groups. The results also did show that the difference was not due to problems with motor control and that the ToL task is a culture-fair instrument for testing planning behaviour.

Verbal learning and memory in adolescent cannabis users, alcohol users and non-users.

PubMed

Solowij, Nadia; Jones, Katy A; Rozman, Megan E; Davis, Sasha M; Ciarrochi, Joseph; Heaven, Patrick C L; Lubman, Dan I; Yücel, Murat

2011-07-01

Long-term heavy cannabis use can result in memory impairment. Adolescent users may be especially vulnerable to the adverse neurocognitive effects of cannabis. In a cross-sectional and prospective neuropsychological study of 181 adolescents aged 16-20 (mean 18.3 years), we compared performance indices from one of the most widely used measures of learning and memory--the Rey Auditory Verbal Learning Test--between cannabis users (n=52; mean 2.4 years of use, 14 days/month, median abstinence 20.3 h), alcohol users (n=67) and non-user controls (n=62) matched for age, education and premorbid intellectual ability (assessed prospectively), and alcohol consumption for cannabis and alcohol users. Cannabis users performed significantly worse than alcohol users and non-users on all performance indices. They recalled significantly fewer words overall (p<0.001), demonstrating impaired learning (p<0.001), retention (p<0.001) and retrieval (p<0.05) (Cohen's d 0.43-0.84). The degree of impairment was associated with the duration, quantity, frequency and age of onset of cannabis use, but was unrelated to alcohol exposure or other drug use. No gender effects were detected and the findings remained after controlling for premorbid intellectual ability. An earlier age of onset of regular cannabis use was associated with worse memory performance after controlling for extent of exposure to cannabis. Despite relatively brief exposure, adolescent cannabis users relative to their age-matched counterparts demonstrated similar memory deficits to those reported in adult long-term heavy users. The results indicate that cannabis adversely affects the developing brain and reinforce concerns regarding the impact of early exposure.

Emotion regulatory function of parent attention to child pain and associated implications for parental pain control behaviour.

PubMed

Vervoort, Tine; Trost, Zina; Sütterlin, Stefan; Caes, Line; Moors, Agnes

2014-08-01

We investigated the function of parental attention to child pain in regulating parental distress and pain control behaviour when observing their child performing a painful (cold pressor) task (CPT); we also studied the moderating role of parental state anxiety. Participants were 62 schoolchildren and one of their parents. Parental attention towards or away from child pain (ie, attend to pain vs avoid pain) was experimentally manipulated during a viewing task pairing unfamiliar children's neutral and pain faces. Before and after the viewing task, parental distress regulation was assessed by heart rate (HR) and heart rate variability (HRV). In a subsequent phase, parents observed their own child perform a CPT task, allowing assessment of parental pain control behaviour (indexed by latency to stop their child's CPT performance) and parental distress, which was assessed via self-report before and after observation of child CPT performance. Eye tracking during the viewing task and self-reported attention to own child's pain confirmed successful attention manipulation. Further, findings indicated that the effect of attentional strategy on parental emotion regulation (indexed by HR, self-report) and pain control behaviour depended on parents' state anxiety. Specifically, whereas low anxious parents reported more distress and demonstrated more pain control behaviour in the Attend to Pain condition, high anxious parents reported more distress and showed more pain control behaviour in the Avoid Pain condition. This inverse pattern was likewise apparent in physiological distress indices (HR) in response to the initial viewing task. Theoretical/clinical implications and further research directions are discussed. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Children's construction task performance and spatial ability: controlling task complexity and predicting mathematics performance.

PubMed

Richardson, Miles; Hunt, Thomas E; Richardson, Cassandra

2014-12-01

This paper presents a methodology to control construction task complexity and examined the relationships between construction performance and spatial and mathematical abilities in children. The study included three groups of children (N = 96); ages 7-8, 10-11, and 13-14 years. Each group constructed seven pre-specified objects. The study replicated and extended previous findings that indicated that the extent of component symmetry and variety, and the number of components for each object and available for selection, significantly predicted construction task difficulty. Results showed that this methodology is a valid and reliable technique for assessing and predicting construction play task difficulty. Furthermore, construction play performance predicted mathematical attainment independently of spatial ability.

Performance of children and adolescents with Asperger syndrome or high-functioning autism on advanced theory of mind tasks.

PubMed

Kaland, Nils; Callesen, Kirsten; Møller-Nielsen, Annette; Mortensen, Erik Lykke; Smith, Lars

2008-07-01

Although a number of advanced theory of mind tasks have been developed, there is a dearth of information on whether performances on different tasks are associated. The present study examined the performance of 21 children and adolescents with diagnoses of Asperger syndrome (AS) and 20 typically developing controls on three advanced theory of mind tasks: The Eyes Task, the Strange Stories, and the Stories from Everyday Life. The participants in the clinical group demonstrated lower performance than the controls on all the three tasks. The pattern of findings, however, indicates that these tasks may share different information-processing requirements in addition to tapping different mentalizing abilities.

Time-History Data of Maneuvers Performed by a Republic F84G Airplane During Squadron Operational Training

NASA Technical Reports Server (NTRS)

Hamer, Harold A.; Mayo, Alton P.

1953-01-01

Preliminary results of one phase of a control-motion study program involving several jet fighter-type airplanes are presented in time-history form and are summarized as maximum measured quantities plotted against indicated airspeed. The results pertain to approximately 1,000 maneuvers performed by a Republic F-84G jet-fighter airplane during squadron operational training. The data include most tactical maneuvers of which the F-84G airplane is capable. Maneuvers were performed at pressure altitudes of 0 to 30,000 feet with indicated airspeeds ranging from the stalling speed to approximately 515 knots.

Using Simulation Speeds to Differentiate Controller Interface Concepts

NASA Technical Reports Server (NTRS)

Trujillo, Anna; Pope, Alan

2008-01-01

This study investigated two concepts: (1) whether speeding a human-in-the-loop simulation (or the subject's "world") scales time stress in such a way as to cause primary task performance to reveal workload differences between experimental conditions and (2) whether using natural hand motions to control the attitude of an aircraft makes controlling the aircraft easier and more intuitive. This was accomplished by having pilots and non-pilots make altitude and heading changes using three different control inceptors at three simulation speeds. Results indicate that simulation speed does affect workload and controllability. The bank and pitch angle error was affected by simulation speed but not by a simulation speed by controller type interaction; this may have been due to the relatively easy flying task. Results also indicate that pilots could control the bank and pitch angle of an aircraft about equally as well with the glove as with the sidestick. Non-pilots approached the pilots ability to control the bank and pitch angle of an aircraft using the positional glove - where the hand angle is directly proportional to the commanded aircraft angle. Therefore, (1) changing the simulation speed lends itself to objectively indexing a subject s workload and may also aid in differentiating among interface concepts based upon performance if the task being studied is sufficiently challenging and (2) using natural body movements to mimic the movement of an airplane for attitude control is feasible.

On the validity of self-report assessment of cognitive abilities: Attentional control scale associations with cognitive performance, emotional adjustment, and personality.

PubMed

Williams, Paula G; Rau, Holly K; Suchy, Yana; Thorgusen, Sommer R; Smith, Timothy W

2017-05-01

Individual differences in attentional control involve the ability to voluntarily direct, shift, and sustain attention. In studies of the role of attentional control in emotional adjustment, social relationships, and vulnerability to the effects of stress, self-report questionnaires are commonly used to measure this construct. Yet, convincing evidence of the association between self-report scales and actual cognitive performance has not been demonstrated. Across 2 independent samples, we examined associations between self-reported attentional control (Attentional Control Scale; ACS), self-reported emotional adjustment, Five-Factor Model personality traits (NEO Personality Inventory-Revised) and performance measures of attentional control. Study 1 examined behavioral performance on the Attention Network Test (ANT; Fan, McCandliss, Sommer, Raz, & Posner, 2002) and the Modified Switching Task (MST; Suchy & Kosson, 2006) in a large sample (n = 315) of healthy young adults. Study 2 (n = 78) examined behavioral performance on standardized neuropsychological tests of attention, including Conner's Continuous Performance Test-II and subtests from the Wechsler Adult Intelligence Scales, Third Edition (WAIS-III; Psychological Corporation, 1997) and Delis-Kaplan Executive Function System (D-KEFS; Delis, Kaplan, & Kramer, 2001). Results indicated that the ACS was largely unrelated to behavioral performance measures of attentional control but was significantly associated with emotional adjustment, neuroticism, and conscientiousness. These findings suggest that although self-reported attentional control may be a useful construct, researchers using the ACS should exercise caution in interpreting it as a proxy for actual cognitive ability or performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Run-off-road and recovery - state estimation and vehicle control strategies

NASA Astrophysics Data System (ADS)

Freeman, P.; Wagner, J.; Alexander, K.

2016-09-01

Despite many advances in vehicle safety technology, traffic fatalities remain a devastating burden on society. With over two-thirds of all fatal single-vehicle crashes occurring off the roadway, run-off-road (ROR) crashes have become the focus of much roadway safety research. Current countermeasures, including roadway infrastructure modifications and some on-board vehicle safety systems, remain limited in their approach as they do not directly address the critical factor of driver behaviour. It has been shown that ROR crashes are often the result of poor driver performance leading up to the crash. In this study, the performance of two control algorithms, sliding control and linear quadratic control, was investigated for use in an autonomous ROR vehicle recovery system. The two controllers were simulated amongst a variety of ROR conditions where typical driver performance was inadequate to safely operate the vehicle. The sliding controller recovered the fastest within the nominal conditions but exhibited large variability in performance amongst the more extreme ROR scenarios. Despite some small sacrifices in lateral error and yaw rate, the linear quadratic controller demonstrated a higher level of consistency and stability amongst the various conditions examined. Overall, the linear quadratic controller recovered the vehicle 25% faster than the sliding controller while using 70% less steering, which combined with its robust performance, indicates its high potential as an autonomous ROR countermeasure.

Temporal Dynamics of Motivation-Cognitive Control Interactions Revealed by High-Resolution Pupillometry

PubMed Central

Chiew, Kimberly S.; Braver, Todd S.

2013-01-01

Motivational manipulations, such as the presence of performance-contingent reward incentives, can have substantial influences on cognitive control. Previous evidence suggests that reward incentives may enhance cognitive performance specifically through increased preparatory, or proactive, control processes. The present study examined reward influences on cognitive control dynamics in the AX-Continuous Performance Task (AX-CPT), using high-resolution pupillometry. In the AX-CPT, contextual cues must be actively maintained over a delay in order to appropriately respond to ambiguous target probes. A key feature of the task is that it permits dissociable characterization of preparatory, proactive control processes (i.e., utilization of context) and reactive control processes (i.e., target-evoked interference resolution). Task performance profiles suggested that reward incentives enhanced proactive control (context utilization). Critically, pupil dilation was also increased on reward incentive trials during context maintenance periods, suggesting trial-specific shifts in proactive control, particularly when context cues indicated the need to overcome the dominant target response bias. Reward incentives had both transient (i.e., trial-by-trial) and sustained (i.e., block-based) effects on pupil dilation, which may reflect distinct underlying processes. The transient pupillary effects were present even when comparing against trials matched in task performance, suggesting a unique motivational influence of reward incentives. These results suggest that pupillometry may be a useful technique for investigating reward motivational signals and their dynamic influence on cognitive control. PMID:23372557

Long-term practice effects on a new skilled motor learning: an electrophysiological study.

PubMed

Fattapposta, F; Amabile, G; Cordischi, M V; Di Venanzio, D; Foti, A; Pierelli, F; D'Alessio, C; Pigozzi, F; Parisi, A; Morrocutti, C

1996-12-01

Cortical functions concerned with the execution of skilled movements can be studied through complex interactive tasks. Skilled performance task (SPT) offers the greatest deal of information about the electrophysiological components reflecting pre-programming, execution of the movement and control of the results. Overall, these components are indicated as "movement-related brain macropotentials' (MRBMs). Among them, Bereitschaftspotential (BP) reflects cerebral processes related to the preparation of movement and skilled performance positivity (SPP) reflects control processes on the result of performance. There is some evidence supporting a training effect on MRBMs, but less clear is whether long-term practice of a skilled activity could modify learning strategies of a new skilled task. We recorded MRBMs in subjects trained for a long time to perform a highly skillful athletic activity, i.e. gun shooting, and in a group of control subjects without any former experience in skilled motor activities. Our findings demonstrated the existence of a relationship between pre-programming and performance control, as suggested by decrease of BP amplitude and increase of SPP amplitude in presence of high levels of performance. Long-term practice seems to develop better control models on performance, that reduce the need of a high mental effort in pre-programming a skilled action.

Magnetic induction of hyperthermia by a modified self-learning fuzzy temperature controller

NASA Astrophysics Data System (ADS)

Wang, Wei-Cheng; Tai, Cheng-Chi

2017-07-01

The aim of this study involved developing a temperature controller for magnetic induction hyperthermia (MIH). A closed-loop controller was applied to track a reference model to guarantee a desired temperature response. The MIH system generated an alternating magnetic field to heat a high magnetic permeability material. This wireless induction heating had few side effects when it was extensively applied to cancer treatment. The effects of hyperthermia strongly depend on the precise control of temperature. However, during the treatment process, the control performance is degraded due to severe perturbations and parameter variations. In this study, a modified self-learning fuzzy logic controller (SLFLC) with a gain tuning mechanism was implemented to obtain high control performance in a wide range of treatment situations. This implementation was performed by appropriately altering the output scaling factor of a fuzzy inverse model to adjust the control rules. In this study, the proposed SLFLC was compared to the classical self-tuning fuzzy logic controller and fuzzy model reference learning control. Additionally, the proposed SLFLC was verified by conducting in vitro experiments with porcine liver. The experimental results indicated that the proposed controller showed greater robustness and excellent adaptability with respect to the temperature control of the MIH system.

[Individual physical performance capacity with physiological and biochemical indicators of stress].

PubMed

Bergert, K D; Nestler, K; Böttger, H; Schettler, R

1989-09-01

22 health male subjects were exposed by a combination of physical exercises and heat. Strain related physiological and biochemical parameters were measured. Different individual reactions were obtained under controlled conditions. In dependence on the individual performance an increased mobilisation of lactat, free fatty acids and catecholamines were found. The determination of aerob physical performance can be applied for the evaluation of working capacity.

Caffeine Does Not Modulate Inhibitory Control

ERIC Educational Resources Information Center

Tieges, Zoe; Snel, Jan; Kok, Albert; Ridderinkhof, K. Richard

2009-01-01

The effects of a 3 mg/kg body weight (BW) dose of caffeine were assessed on behavioral indices of response inhibition. To meet these aims, we selected a modified AX version of the Continuous Performance Test (CPT), the stop task, and the flanker task. In three double-blind, placebo-controlled, within-subjects experiments, these tasks were…

STABLE ISOTOPE SIGNATURES OF MUCUS OF STEELHEAD TROUT IN A CONTROLLED DIET SWITCH EXPERIMENT

EPA Science Inventory

Our work has shown that fish mucus can serve as a very rapid indicator of diet switching in fish. We performed diet switching studies of steelhead trout in a controlled hatchery setting using specially formulated low delta 15N signature and high delta 15N signature diets. To ou...

Performance Enhancement of a Vertical Tail Model with Sweeping Jet Actuators

NASA Technical Reports Server (NTRS)

Seele, Roman; Graff, Emilio; Lin, John; Wygnanski, Israel

2013-01-01

Active Flow Control (AFC) experiments performed at the Caltech Lucas Adaptive Wall Wind Tunnel on a 12%-thick, generic vertical tail model indicated that sweeping jets emanating from the trailing edge (TE) of the vertical stabilizer significantly increased the side force coefficient for a wide range of rudder deflection angles and yaw angles at free-stream velocities approaching takeoff rotation speed. The results indicated that 2% blowing momentum coefficient (C(sub mu) increased the side force in excess of 50% at the maximum conventional rudder deflection angle in the absence of yaw. Even C(sub mu) = 0.5% increased the side force in excess of 20% under these conditions. This effort was sponsored by the NASA Environmentally Responsible Aviation (ERA) project and the successful demonstration of this flow-control application could have far reaching implications. It could lead to effective applications of AFC technologies on key aircraft control surfaces and lift enhancing devices (flaps) that would aid in reduction of fuel consumption through a decrease in size and weight of wings and control surfaces or a reduction of the noise footprint due to steeper climb and descent.

Flight Test of a Propulsion-Based Emergency Control System on the MD-11 Airplane with Emphasis on the Lateral Axis

NASA Technical Reports Server (NTRS)

Burken, John J.; Burcham, Frank W., Jr.; Maine, Trindel A.; Feather, John; Goldthorpe, Steven; Kahler, Jeffrey A.

1996-01-01

A large, civilian, multi-engine transport MD-11 airplane control system was recently modified to perform as an emergency backup controller using engine thrust only. The emergency backup system, referred to as the propulsion-controlled aircraft (PCA) system, would be used if a major primary flight control system fails. To allow for longitudinal and lateral-directional control, the PCA system requires at least two engines and is implemented through software modifications. A flight-test program was conducted to evaluate the PCA system high-altitude flying characteristics and to demonstrate its capacity to perform safe landings. The cruise flight conditions, several low approaches and one landing without any aerodynamic flight control surface movement, were demonstrated. This paper presents results that show satisfactory performance of the PCA system in the longitudinal axis. Test results indicate that the lateral-directional axis of the system performed well at high attitude but was sluggish and prone to thermal upsets during landing approaches. Flight-test experiences and test techniques are also discussed with emphasis on the lateral-directional axis because of the difficulties encountered in flight test.

A new perspective on the interplay between self-control and cognitive performance: Modeling progressive depletion patterns.

PubMed

Lindner, Christoph; Nagy, Gabriel; Ramos Arhuis, Wolfgang Andreas; Retelsdorf, Jan

2017-01-01

Exerting self-control in a first task weakens self-control performance in a subsequent unrelated task (ego depletion). In self-control research new strategies are required to investigate the ego-depletion effect, which has recently been shown to be more fragile than previously assumed. Moreover, the relation between ego depletion and trait self-control is still unclear, as various studies have reported heterogeneous findings concerning the interplay of both variables. We addressed these lacunas by drawing on a sample of N = 120 students, who participated in two test sessions. In the first test session, we assessed trait self-control and several control variables. The second test session followed an experimental design and tested the effects of ego depletion on invested effort and cognitive performance trajectories in an ecologically valid computer-based assessment setting (i.e., a 30-minute mathematical problem-solving and reasoning test). Trait self-control was then used as a moderator of the ego-depletion effect. Combining an established ego-depletion paradigm (i.e., the sequential-task paradigm) with multilevel modeling of time-on-task and performance changes, our results indicate (1) that trait self-control predicted the motivation to solve cognitive tasks, (2) that ego depletion led to a progressive performance decrease, and (3) that the negative effect of ego depletion on performance was stronger for students with high trait self-control. Additional analyses revealed that our results could not be alternatively explained by fatigue effects. All effects were robust even after controlling for the students' cognitive abilities, which are known to be closely related to mathematical performance. Our results provide evidence that the self-control invested in order to keep performance at a consistently high level wanes over time. By modeling progressive ego-depletion effects while considering trait self-control, we provide an alternative approach that may help future researchers to investigate the underlying mechanisms of self-control.

A new perspective on the interplay between self-control and cognitive performance: Modeling progressive depletion patterns

PubMed Central

Nagy, Gabriel; Ramos Arhuis, Wolfgang Andreas; Retelsdorf, Jan

2017-01-01

Exerting self-control in a first task weakens self-control performance in a subsequent unrelated task (ego depletion). In self-control research new strategies are required to investigate the ego-depletion effect, which has recently been shown to be more fragile than previously assumed. Moreover, the relation between ego depletion and trait self-control is still unclear, as various studies have reported heterogeneous findings concerning the interplay of both variables. We addressed these lacunas by drawing on a sample of N = 120 students, who participated in two test sessions. In the first test session, we assessed trait self-control and several control variables. The second test session followed an experimental design and tested the effects of ego depletion on invested effort and cognitive performance trajectories in an ecologically valid computer-based assessment setting (i.e., a 30-minute mathematical problem-solving and reasoning test). Trait self-control was then used as a moderator of the ego-depletion effect. Combining an established ego-depletion paradigm (i.e., the sequential-task paradigm) with multilevel modeling of time-on-task and performance changes, our results indicate (1) that trait self-control predicted the motivation to solve cognitive tasks, (2) that ego depletion led to a progressive performance decrease, and (3) that the negative effect of ego depletion on performance was stronger for students with high trait self-control. Additional analyses revealed that our results could not be alternatively explained by fatigue effects. All effects were robust even after controlling for the students’ cognitive abilities, which are known to be closely related to mathematical performance. Our results provide evidence that the self-control invested in order to keep performance at a consistently high level wanes over time. By modeling progressive ego-depletion effects while considering trait self-control, we provide an alternative approach that may help future researchers to investigate the underlying mechanisms of self-control. PMID:28662176

PDC-bit performance under simulated borehole conditions

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

Anderson, E.E.; Azar, J.J.

1993-09-01

Laboratory drilling tests were used to investigate the effects of pressure on polycrystalline-diamond-compact (PDC) drill-bit performance. Catoosa shale core samples were drilled with PDC and roller-cone bits at up to 1,750-psi confining pressure. All tests were conducted in a controlled environment with a full-scale laboratory drilling system. Test results indicate, that under similar operating conditions, increases in confining pressure reduce PDC-bit performance as much as or more than conventional-rock-bit performance. Specific energy calculations indicate that a combination of rock strength, chip hold-down, and bit balling may have reduced performance. Quantifying the degree to which pressure reduces PDC-bit performance will helpmore » researchers interpret test results and improve bit designs and will help drilling engineers run PDC bits more effectively in the field.« less

An Intervention Study on Mental Computation for Second Graders in Taiwan

ERIC Educational Resources Information Center

Yang, Der-Ching; Huang, Ke-Lun

2014-01-01

The authors compared the mental computation performance and mental strategies used by an experimental Grade 2 class and a control Grade 2 class before and after instructional intervention. Results indicate that students in the experimental group had better performance on mental computation. The use of mental strategies (counting, separation,…

Relationships among Meditation, Perfectionism, Mindfulness, and Performance Anxiety among Collegiate Music Students

ERIC Educational Resources Information Center

Diaz, Frank M.

2018-01-01

I examined the use of meditation practices among collegiate-level musicians (N = 255), along with the degree to which these practices contributed to music performance anxiety (MPA) when controlling for trait perfectionism and trait mindfulness. Findings indicated that approximately 48% of the participants sampled had engaged in meditation during…

Performance-Based Rewards and Work Stress

ERIC Educational Resources Information Center

Ganster, Daniel C.; Kiersch, Christa E.; Marsh, Rachel E.; Bowen, Angela

2011-01-01

Even though reward systems play a central role in the management of organizations, their impact on stress and the well-being of workers is not well understood. We review the literature linking performance-based reward systems to various indicators of employee stress and well-being. Well-controlled experiments in field settings suggest that certain…

Reaction time and accuracy in individuals with aphasia during auditory vigilance tasks.

PubMed

Laures, Jacqueline S

2005-11-01

Research indicates that attentional deficits exist in aphasic individuals. However, relatively little is known about auditory vigilance performance in individuals with aphasia. The current study explores reaction time (RT) and accuracy in 10 aphasic participants and 10 nonbrain-damaged controls during linguistic and nonlinguistic auditory vigilance tasks. Findings indicate that the aphasic group was less accurate during both tasks than the control group, but was not slower in their accurate responses. Further examination of the data revealed variability in the aphasic participants' RT contributing to the lower accuracy scores.

Interactive effects of trait and state affect on top-down control of attention

PubMed Central

Hur, Juyoen; Miller, Gregory A.; McDavitt, Jenika R.B.; Spielberg, Jeffrey M.; Crocker, Laura D.; Infantolino, Zachary P.; Towers, David N.; Warren, Stacie L.

2015-01-01

Few studies have investigated how attentional control is affected by transient affective states while taking individual differences in affective traits into consideration. In this study, participants completed a color-word Stroop task immediately after undergoing a positive, neutral or negative affective context manipulation (ACM). Behavioral performance was unaffected by any ACM considered in isolation. For individuals high in trait negative affect (NA), performance was impaired by the negative but not the positive or neutral ACM. Neuroimaging results indicate that activity in primarily top-down control regions of the brain (inferior frontal gyrus and dorsal anterior cingulate cortex) was suppressed in the presence of emotional arousal (both negative and positive ACMs). This effect appears to have been exacerbated or offset by co-occurring activity in other top-down control regions (parietal) and emotion processing regions (orbitofrontal cortex, amygdala and nucleus accumbens) as a function of the valence of state affect (positive or negative) and trait affect (trait NA or trait PA). Neuroimaging results are consistent with behavioral findings. In combination, they indicate both additive and interactive influences of trait and state affect on top-down control of attention. PMID:25556211

Experimental Validation of an Integrated Controls-Structures Design Methodology

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.; Gupta, Sandeep; Elliot, Kenny B.; Walz, Joseph E.

1996-01-01

The first experimental validation of an integrated controls-structures design methodology for a class of large order, flexible space structures is described. Integrated redesign of the controls-structures-interaction evolutionary model, a laboratory testbed at NASA Langley, was described earlier. The redesigned structure was fabricated, assembled in the laboratory, and experimentally tested against the original structure. Experimental results indicate that the structure redesigned using the integrated design methodology requires significantly less average control power than the nominal structure with control-optimized designs, while maintaining the required line-of-sight pointing performance. Thus, the superiority of the integrated design methodology over the conventional design approach is experimentally demonstrated. Furthermore, amenability of the integrated design structure to other control strategies is evaluated, both analytically and experimentally. Using Linear-Quadratic-Guassian optimal dissipative controllers, it is observed that the redesigned structure leads to significantly improved performance with alternate controllers as well.

Experimental aeroelastic control using adaptive wing model concepts

NASA Astrophysics Data System (ADS)

Costa, Antonio P.; Moniz, Paulo A.; Suleman, Afzal

2001-06-01

The focus of this study is to evaluate the aeroelastic performance and control of adaptive wings. Ailerons and flaps have been designed and implemented into 3D wings for comparison with adaptive structures and active aerodynamic surface control methods. The adaptive structures concept, the experimental setup and the control design are presented. The wind-tunnel tests of the wing models are presented for the open- and closed-loop systems. The wind tunnel testing has allowed for quantifying the effectiveness of the piezoelectric vibration control of the wings, and also provided performance data for comparison with conventional aerodynamic control surfaces. The results indicate that a wing utilizing skins as active structural elements with embedded piezoelectric actuators can be effectively used to improve the aeroelastic response of aeronautical components. It was also observed that the control authority of adaptive wings is much greater than wings using conventional aerodynamic control surfaces.

Emotional and cognitive influences in air traffic controller tasks: An investigation using a virtual environment?

PubMed

Truschzinski, Martina; Betella, Alberto; Brunnett, Guido; Verschure, Paul F M J

2018-05-01

Air traffic controllers are required to perform complex tasks which require attention and high precision. This study investigates how the difficulty of such tasks influences emotional states, cognitive workload and task performance. We use quantitative and qualitative measurements, including the recording of pupil dilation and changes in affect using questionnaires. Participants were required to perform a number of air traffic control tasks using the immersive human accessible Virtual Reality space in the "eXperience Induction Machine". Based on the data collected, we developed and validated a model which integrates personality, workload and affective theories. Our results indicate that the difficulty of an air traffic control task has a direct influence on cognitive workload as well as on the self-reported mood; whereas both mood and workload seem to change independently. In addition, we show that personality, in particular neuroticism, affects both mood and performance of the participants. Copyright © 2018 Elsevier Ltd. All rights reserved.

Indicators of the Practice of Power in Language Classrooms

ERIC Educational Resources Information Center

Milal, A. Dzo'ul

2011-01-01

This paper attempts to reveal some strategies performed by a teacher which indicate that s/he is exercising power in managing and conducting language teaching and learning process. Such power may be manifested in terms of the frequency of directives or of the holding of control over the interaction process. Despite the fact that exercising power…

Impacts of Mercury Pollution Controls on Atmospheric Mercury Concentration and Occupational Mercury Exposure in a Hospital.

PubMed

Li, Ping; Yang, Yan; Xiong, Wuyan

2015-12-01

Mercury (Hg) and Hg-containing products are used in a wide range of settings in hospitals. Hg pollution control measures were carried out in the pediatric ward of a hospital to decrease the possibility of Hg pollution occurring and to decrease occupational Hg exposure. Total gaseous Hg (TGM) concentrations in the pediatric ward and hair and urine Hg concentrations for the pediatric staff were determined before and after the Hg pollution control measures had been implemented. A questionnaire survey performed indicated that the pediatric staff had little understanding of Hg pollution and that appropriate disposal techniques were not always used after Hg leakage. TGM concentrations in the pediatric ward and urine Hg (UHg) concentrations for the pediatric staff were 25.7 and 22.2% lower, respectively, after the Hg pollution control measures had been implemented than before, which indicated that the control measures were effective. However, TGM concentrations in the pediatric ward remained significantly higher than background concentrations and UHg concentrations for the pediatric staff were remained significantly higher than the concentrations in control group, indicating continued existence of certain Hg pollution.

Sex differences in verbal fluency during adolescence: a functional magnetic resonance imaging study in gender dysphoric and control boys and girls.

PubMed

Soleman, Remi S; Schagen, Sebastian E E; Veltman, Dick J; Kreukels, Baudewijntje P C; Cohen-Kettenis, Peggy T; Lambalk, Cornelis B; Wouters, Femke; Delemarre-van de Waal, Henriette A

2013-08-01

In the literature, verbal fluency (VF) is generally described as a female-favoring task. Although it is conceivable that this sex difference only evolves during adolescence or adulthood under influence of sex steroids, this has never been investigated in young adolescents. First, to assess sex differences in VF performance and regional brain activation in adolescents. Second, to determine if untreated transsexual adolescents differ from their sex of birth with regard to VF performance and regional brain activation. Twenty-five boys, 26 girls, 8 Male-to-Female transsexual adolescents (MtFs), and 14 Female-to-Male transsexual adolescents (FtMs) were tested in a cross-sectional study, while performing a phonetic and semantic VF task within an MRI scanner. Functional MRI response during VF task. Boys and girls produced similar amounts of words, but the group MtFs produced significantly more words in the phonetic condition compared to control boys, girls, and FtMs. During the semantic condition, no differences were found. With regard to brain activity, control boys showed more activation in the right Rolandic operculum, a small area adjacent to Broca's area, compared to girls. No significant differences in brain activity were found comparing transsexual adolescents, although sub-threshold activation was found in the right Rolandic operculum indicating a trendwise increase in activation from control girls to FtMs to MtFs to control boys. The better performance of MtFs is consistent with our expectation that MtFs perform better on female-favoring tasks. Moreover, they produced more words than girls and FtMs. Even though a trendwise linear increase in brain activity between the four groups only approached significance, it may indicate differences in individuals with gender identity disorder compared to their birth sex. Although our findings should thus be interpreted with caution, they suggest a biological basis for both transgender groups performing in-between the two sexes. © 2013 International Society for Sexual Medicine.

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

PubMed

Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

2015-09-18

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling

PubMed Central

Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

2015-01-01

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608

Mapping the structure of perceptual and visual-motor abilities in healthy young adults.

PubMed

Wang, Lingling; Krasich, Kristina; Bel-Bahar, Tarik; Hughes, Lauren; Mitroff, Stephen R; Appelbaum, L Gregory

2015-05-01

The ability to quickly detect and respond to visual stimuli in the environment is critical to many human activities. While such perceptual and visual-motor skills are important in a myriad of contexts, considerable variability exists between individuals in these abilities. To better understand the sources of this variability, we assessed perceptual and visual-motor skills in a large sample of 230 healthy individuals via the Nike SPARQ Sensory Station, and compared variability in their behavioral performance to demographic, state, sleep and consumption characteristics. Dimension reduction and regression analyses indicated three underlying factors: Visual-Motor Control, Visual Sensitivity, and Eye Quickness, which accounted for roughly half of the overall population variance in performance on this battery. Inter-individual variability in Visual-Motor Control was correlated with gender and circadian patters such that performance on this factor was better for males and for those who had been awake for a longer period of time before assessment. The current findings indicate that abilities involving coordinated hand movements in response to stimuli are subject to greater individual variability, while visual sensitivity and occulomotor control are largely stable across individuals. Copyright © 2015 Elsevier B.V. All rights reserved.

Cognitive performance and electrophysiological indices of cognitive control: a validation study of conflict adaptation.

PubMed

Clayson, Peter E; Larson, Michael J

2012-05-01

Psychiatric and neurologic disorders are associated with deficits in the postconflict recruitment of cognitive control. The primary aim of this study was to validate the relationship between cognitive functioning and indices of conflict adaptation. Event-related potentials were obtained from 89 healthy individuals who completed an Eriksen flanker task. Neuropsychological domains tested included memory, verbal fluency, and attention/executive functioning. Behavioral measures and N2 amplitudes showed significant conflict adaptation (i.e., previous-trial congruencies influenced current-trial measures). Higher scores on the attention/executive functioning and verbal fluency domains were associated with larger incongruent-trial N2 conflict adaptation; measures of cognitive functioning were not related to behavioral indices. This study provides initial validation of N2 conflict adaptation effects as cognitive function-related aspects of cognitive control. Copyright © 2012 Society for Psychophysiological Research.

CSI computer system/remote interface unit acceptance test results

NASA Technical Reports Server (NTRS)

Sparks, Dean W., Jr.

1992-01-01

The validation tests conducted on the Control/Structures Interaction (CSI) Computer System (CCS)/Remote Interface Unit (RIU) is discussed. The CCS/RIU consists of a commercially available, Langley Research Center (LaRC) programmed, space flight qualified computer and a flight data acquisition and filtering computer, developed at LaRC. The tests were performed in the Space Structures Research Laboratory (SSRL) and included open loop excitation, closed loop control, safing, RIU digital filtering, and RIU stand alone testing with the CSI Evolutionary Model (CEM) Phase-0 testbed. The test results indicated that the CCS/RIU system is comparable to ground based systems in performing real-time control-structure experiments.

Multicyclic Controllable Twist Rotor Data Analysis

NASA Technical Reports Server (NTRS)

Wei, F. S.; Weisbrich, A. L.

1979-01-01

Rsults provide functional relationship between rotor performance, blade vibratory loads and dual control settings and indicate that multicyclic control produced significant reductions in blade flatwise bending moments and blade root actuator control loads. Higher harmonic terms of servo flap deflection were found to be most pronounced in flatwise bending moment, transmission vertical vibration and pitch link vibratory load equations. The existing test hardware represents a satisfactory configuration for demonstrating MCTR technology and defining a data base for additional wind tunnel testing.

Non-dimensionalised closed-form parametric analysis of semi-active vehicle suspensions using a quarter-car model

NASA Astrophysics Data System (ADS)

Ahmadian, Mehdi; Blanchard, Emmanuel

2011-02-01

This article provides a non-dimensionalised closed-form analysis of semi-active vehicle suspensions, using a quarter-car model. The derivation of the closed-form solutions for three indices that can be used for ride comfort, vehicle handling, and stability are presented based on non-dimensionalised suspension parameters. The behaviour of semi-active vehicle suspensions is evaluated using skyhook, groundhook, and hybrid control policies, and compared with passive suspensions. The relationship between vibration isolation, suspension deflection, and road holding is studied, using three performance indices based on the mean square of the sprung mass acceleration, rattle space, and tyre deflection, respectively. The results of the study indicate that the hybrid control policy yields significantly better comfort than a passive suspension, without reducing the road-holding quality or increasing the suspension displacement for typical passenger cars. The results also indicate that for typical passenger cars, the hybrid control policy results in a better compromise between comfort, road holding and suspension travel requirements than both the skyhook and groundhook control methods.

Redesign of a Variable-Gain Output Feedback Longitudinal Controller Flown on the High-Alpha Research Vehicle (HARV)

NASA Technical Reports Server (NTRS)

Ostroff, Aaron J.

1998-01-01

This paper describes a redesigned longitudinal controller that flew on the High-Alpha Research Vehicle (HARV) during calendar years (CY) 1995 and 1996. Linear models are developed for both the modified controller and a baseline controller that was flown in CY 1994. The modified controller was developed with three gain sets for flight evaluation, and several linear analysis results are shown comparing the gain sets. A Neal-Smith flying qualities analysis shows that performance for the low- and medium-gain sets is near the level 1 boundary, depending upon the bandwidth assumed, whereas the high-gain set indicates a sensitivity problem. A newly developed high-alpha Bode envelope criterion indicates that the control system gains may be slightly high, even for the low-gain set. A large motion-base simulator in the United Kingdom was used to evaluate the various controllers. Desired performance, which appeared to be satisfactory for flight, was generally met with both the low- and medium-gain sets. Both the high-gain set and the baseline controller were very sensitive, and it was easy to generate pilot-induced oscillation (PIO) in some of the target-tracking maneuvers. Flight target-tracking results varied from level 1 to level 3 and from no sensitivity to PIO. These results were related to pilot technique and whether actuator rate saturation was encountered.

Exploration of malingering indices in the Wechsler Adult Intelligence Scale-Fourth Edition Digit Span subtest.

PubMed

Reese, Caitlin S; Suhr, Julie A; Riddle, Tara L

2012-03-01

Prior research shows that Digit Span is a useful embedded measure of malingering. However, the Wechsler Adult Intelligence Scale-IV (Wechsler, 2008) altered Digit Span in meaningful ways, necessitating another look at Digit Span as an embedded measure of malingering. Using a simulated malingerer design, we examined the predictive accuracy of existing Digit Span validity indices and explored whether patterns of performance utilizing the new version would provide additional evidence for malingering. Undergraduates with a history of mild head injury performed with best effort or simulated impaired cognition and were also compared with a large sample of non-head-injured controls. Previously established cutoffs for the age-corrected scaled score and Reliable Digit Span (RDS) performed similarly in the present samples. Patterns of RDS length using all three subscales of the new scale were different in malingerers when compared with both head-injured and non-head-injured controls. Two potential alternative RDS scores were introduced, which showed better sensitivity than the traditional RDS, while retaining specificity to malingering.

Reduced Specificity of Autobiographical Memory and Depression

PubMed Central

Dalgleish, Tim; Williams, J. Mark G.; Golden, Ann-Marie J.; Perkins, Nicola; Barrett, Lisa Feldman; Barnard, Phillip J.; Yeung, Cecilia Au; Murphy, Victoria; Elward, Rachael; Tchanturia, Kate; Watkins, Edward

2007-01-01

It has been widely established that depressed mood states and clinical depression, as well as a range of other psychiatric disorders, are associated with a relative difficulty in accessing specific autobiographical information in response to emotion-related cue words on an Autobiographical Memory Test (AMT; J. M. G. Williams & K. Broadbent, 1986). In 8 studies the authors examined the extent to which this relationship is a function of impaired executive control associated with these mood states and clinical disorders. Studies 1–4 demonstrated that performance on the AMT is associated with performance on measures of executive control, independent of depressed mood. Furthermore, Study 1 showed that executive control (as measured by verbal fluency) mediated the relationship between both depressed mood and a clinical diagnosis of eating disorder and AMT performance. Using a stratified sample in Study 5, the authors confirmed the positive association between depressed mood and impaired performance on the AMT. Studies 6–8 involved experimental manipulations of the parameters of the AMT designed to further indicate that reduced executive control is to a significant extent driving the relationship between depressed mood and AMT performance. The potential role of executive control in accounting for other aspects of the AMT literature is discussed. PMID:17324083

Quantitative Measurement of Vocal Fold Vibration in Male Radio Performers and Healthy Controls Using High-Speed Videoendoscopy

PubMed Central

Warhurst, Samantha; McCabe, Patricia; Heard, Rob; Yiu, Edwin; Wang, Gaowu; Madill, Catherine

2014-01-01

Purpose Acoustic and perceptual studies show a number of differences between the voices of radio performers and controls. Despite this, the vocal fold kinematics underlying these differences are largely unknown. Using high-speed videoendoscopy, this study sought to determine whether the vocal vibration features of radio performers differed from those of non-performing controls. Method Using high-speed videoendoscopy, recordings of a mid-phonatory/i/ in 16 male radio performers (aged 25–52 years) and 16 age-matched controls (aged 25–52 years) were collected. Videos were extracted and analysed semi-automatically using High-Speed Video Program, obtaining measures of fundamental frequency (f0), open quotient and speed quotient. Post-hoc analyses of sound pressure level (SPL) were also performed (n = 19). Pearson's correlations were calculated between SPL and both speed and open quotients. Results Male radio performers had a significantly higher speed quotient than their matched controls (t = 3.308, p = 0.005). No significant differences were found for f0 or open quotient. No significant correlation was found between either open or speed quotient with SPL. Discussion A higher speed quotient in male radio performers suggests that their vocal fold vibration was characterised by a higher ratio of glottal opening to closing times than controls. This result may explain findings of better voice quality, higher equivalent sound level and greater spectral tilt seen in previous research. Open quotient was not significantly different between groups, indicating that the durations of complete vocal fold closure were not different between the radio performers and controls. Further validation of these results is required to determine the aetiology of the higher speed quotient result and its implications for voice training and clinical management in performers. PMID:24971625

Transmission loss characteristics of aircraft sidewall systems to control cabin interior noise

NASA Astrophysics Data System (ADS)

Yesil, Oktay; Serati, Paul M.; Hofbeck, Eric V.; Glover, Billy M.

We have explored the possibility of using new, light weight, and acoustically effective materials on aircraft interiors to control noise. The sidewall system elements were evaluated for increased TL in the laboratory. Measured TL for a given configuration, relative to a baseline, was used as an indication of the TL change to be expected for modifications. Test data were in good agreement with the predicted levels. The TL contributions due to all sidewall components were important for interior cabin noise control. Polyimide foam insulation was inferior to fiberglass in the mid-frequency range; however, foam was a better performer at high frequencies. Fiberglass/polyimide foam composite blankets, with less weight, provided noise reductions similar to fiberglass. 'Premium' fiberglass was slightly better performer than the standard fiberglass. Solid fiberglass interior trim panel provided adequate noise performance. Production-type trim attachment design could be improved to control flanking path for sound transmission.

Towards the Engineering of Dependable P2P-Based Network Control — The Case of Timely Routing Control Messages

NASA Astrophysics Data System (ADS)

Tutschku, Kurt; Nakao, Akihiro

This paper introduces a methodology for engineering best-effort P2P algorithms into dependable P2P-based network control mechanism. The proposed method is built upon an iterative approach consisting of improving the original P2P algorithm by appropriate mechanisms and of thorough performance assessment with respect to dependability measures. The potential of the methodology is outlined by the example of timely routing control for vertical handover in B3G wireless networks. In detail, the well-known Pastry and CAN algorithms are enhanced to include locality. By showing how to combine algorithmic enhancements with performance indicators, this case study paves the way for future engineering of dependable network control mechanisms through P2P algorithms.

The effect of conscious control on handwriting in children with attention deficit hyperactivity disorder.

PubMed

Tucha, Oliver; Lange, Klaus W

2005-08-01

Two experiments were performed regarding the effect of conscious control on handwriting fluency in healthy adults and ADHD children. First, 26 healthy students were asked to write a sentence under different conditions. The results indicate that automated handwriting movements are independent from visual feedback. Second, the writing performance of 12 children with ADHD was examined on their usual medication with methylphenidate and under placebo. In comparison to placebo, medication with methylphenidate resulted in a reduced fluency of handwriting. Automated handwriting movements could be elicited in children with ADHD on medication. The results suggest that both visual and mental control of handwriting movements affect the automation of handwriting movements. Furthermore, a simple training procedure was designed and performed in a case study of a boy with ADHD.

Performance of an asymmetric short annular diffuser with a nondiverging inner wall using suction. [control of radial profiles of diffuser exit velocity

NASA Technical Reports Server (NTRS)

Juhasz, A.

1974-01-01

The performance of a short highly asymmetric annular diffuser equipped with wall bleed (suction) capability was evaluated at nominal inlet Mach numbers of 0.188, 0.264, and 0.324 with the inlet pressure and temperature at near ambient values. The diffuser had an area ratio of 2.75 and a length- to inlet-height ratio of 1.6. Results show that the radial profiles of diffuser exit velocity could be controlled from a severely hub peaked to a slightly tip biased form by selective use of bleed. At the same time, other performance parameters were also improved. These results indicate the possible application of the diffuser bleed technique to control flow profiles to gas turbine combustors.

Performance of Swashplateless Ultralight Helicopter Rotor with Trailing-edge Flaps for Primary Flight Control

NASA Technical Reports Server (NTRS)

Shen, Jin-Wei; Chopra, Inderjit

2003-01-01

The objective of present study is to evaluate the rotor performance, trailing-edge deflections and actuation requirement of a helicopter rotor with trailing-edge flap system for primary flight control. The swashplateless design is implemented by modifying a two-bladed teetering rotor of an production ultralight helicopter through the use of plain flaps on the blades, and by replacing the pitch link to fixed system control system assembly with a root spring. A comprehensive rotorcraft analysis based on UMARC is carried out to obtain the results for both the swashplateless and a conventional baseline rotor configuration. The predictions show swashplateless configuration achieve superior performance than the conventional rotor attributed from reduction of parasite drag by eliminating swashplate mechanic system. It is indicated that optimal selection of blade pitch index angle, flap location, length, and chord ratio reduces flap deflections and actuation requirements, however, has virtually no effect on rotor performance.

Child Effortful Control, Teacher-student Relationships, and Achievement in Academically At-risk Children: Additive and Interactive Effects

PubMed Central

Liew, Jeffrey; Chen, Qi; Hughes, Jan N.

2009-01-01

The joint contributions of child effortful control (using inhibitory control and task accuracy as behavioral indices) and positive teacher-student relationships at first grade on reading and mathematics achievement at second grade were examined in 761 children who were predominantly from low-income and ethnic minority backgrounds and assessed to be academically at-risk at entry to first grade. Analyses accounted for clustering effects, covariates, baselines of effortful control measures, and prior levels of achievement. Even with such conservative statistical controls, interactive effects were found for task accuracy and positive teacher-student relationships on future achievement. Results suggest that task accuracy served as a protective factor so that children with high task accuracy performed well academically despite not having positive teacher-student relationships. Further, positive teacher-student relationships served as a compensatory factor so that children with low task accuracy performed just as well as those with high task accuracy if they were paired with a positive and supportive teacher. Importantly, results indicate that the influence of positive teacher-student relationships on future achievement was most pronounced for students with low effortful control on tasks that require fine motor skills, accuracy, and attention-related skills. Study results have implications for narrowing achievement disparities for academically at-risk children. PMID:20161421

Child Effortful Control, Teacher-student Relationships, and Achievement in Academically At-risk Children: Additive and Interactive Effects.

PubMed

Liew, Jeffrey; Chen, Qi; Hughes, Jan N

2010-01-01

The joint contributions of child effortful control (using inhibitory control and task accuracy as behavioral indices) and positive teacher-student relationships at first grade on reading and mathematics achievement at second grade were examined in 761 children who were predominantly from low-income and ethnic minority backgrounds and assessed to be academically at-risk at entry to first grade. Analyses accounted for clustering effects, covariates, baselines of effortful control measures, and prior levels of achievement. Even with such conservative statistical controls, interactive effects were found for task accuracy and positive teacher-student relationships on future achievement. Results suggest that task accuracy served as a protective factor so that children with high task accuracy performed well academically despite not having positive teacher-student relationships. Further, positive teacher-student relationships served as a compensatory factor so that children with low task accuracy performed just as well as those with high task accuracy if they were paired with a positive and supportive teacher. Importantly, results indicate that the influence of positive teacher-student relationships on future achievement was most pronounced for students with low effortful control on tasks that require fine motor skills, accuracy, and attention-related skills. Study results have implications for narrowing achievement disparities for academically at-risk children.

An adaptive learning control system for aircraft

NASA Technical Reports Server (NTRS)

Mekel, R.; Nachmias, S.

1978-01-01

A learning control system and its utilization as a flight control system for F-8 Digital Fly-By-Wire (DFBW) research aircraft is studied. The system has the ability to adjust a gain schedule to account for changing plant characteristics and to improve its performance and the plant's performance in the course of its own operation. Three subsystems are detailed: (1) the information acquisition subsystem which identifies the plant's parameters at a given operating condition; (2) the learning algorithm subsystem which relates the identified parameters to predetermined analytical expressions describing the behavior of the parameters over a range of operating conditions; and (3) the memory and control process subsystem which consists of the collection of updated coefficients (memory) and the derived control laws. Simulation experiments indicate that the learning control system is effective in compensating for parameter variations caused by changes in flight conditions.

Test anxiety, perfectionism, goal orientation, and academic performance.

PubMed

Eum, KoUn; Rice, Kenneth G

2011-03-01

Dimensions of perfectionism and goal orientation have been reported to have differential relationships with test anxiety. However, the degree of inter-relationship between different dimensions of perfectionism, the 2 × 2 model of goal orientations proposed by Elliot and McGregor, cognitive test anxiety, and academic performance indicators is not known. Based on data from 134 university students, we conducted correlation and regression analyses to test associations between adaptive and maladaptive perfectionism, four types of goal orientations, cognitive test anxiety, and two indicators of academic performance: proximal cognitive performance on a word list recall test and distal academic performance in terms of grade point average. Cognitive test anxiety was inversely associated with both performance indicators, and positively associated with maladaptive perfectionism and avoidance goal orientations. Adaptive and maladaptive perfectionism accounted for significant variance in cognitive test anxiety after controlling for approach and avoidance goal orientations. Overall, nearly 50% of the variance in cognitive test anxiety could be attributed to gender, goal orientations, and perfectionism. Results suggested that students who are highly test anxious are likely to be women who endorse avoidance goal orientations and are maladaptively perfectionistic.

Dissociation between controlled and automatic processes in the behavioral variant of fronto-temporal dementia.

PubMed

Collette, Fabienne; Van der Linden, Martial; Salmon, Eric

2010-01-01

A decline of cognitive functioning affecting several cognitive domains was frequently reported in patients with frontotemporal dementia. We were interested in determining if these deficits can be interpreted as reflecting an impairment of controlled cognitive processes by using an assessment tool specifically developed to explore the distinction between automatic and controlled processes, namely the process dissociation procedure (PDP) developed by Jacoby. The PDP was applied to a word stem completion task to determine the contribution of automatic and controlled processes to episodic memory performance and was administered to a group of 12 patients with the behavioral variant of frontotemporal dementia (bv-FTD) and 20 control subjects (CS). Bv-FTD patients obtained a lower performance than CS for the estimates of controlled processes, but no group differences was observed for estimates of automatic processes. The between-groups comparison of the estimates of controlled and automatic processes showed a larger contribution of automatic processes to performance in bv-FTD, while a slightly more important contribution of controlled processes was observed in control subjects. These results are clearly indicative of an alteration of controlled memory processes in bv-FTD.

Performance analysis of two-degree of freedom fractional order PID controllers for robotic manipulator with payload.

PubMed

Sharma, Richa; Gaur, Prerna; Mittal, A P

2015-09-01

The robotic manipulators are multi-input multi-output (MIMO), coupled and highly nonlinear systems. The presence of external disturbances and time-varying parameters adversely affects the performance of these systems. Therefore, the controller designed for these systems should effectively deal with such complexities, and it is an intriguing task for control engineers. This paper presents two-degree of freedom fractional order proportional-integral-derivative (2-DOF FOPID) controller scheme for a two-link planar rigid robotic manipulator with payload for trajectory tracking task. The tuning of all controller parameters is done using cuckoo search algorithm (CSA). The performance of proposed 2-DOF FOPID controllers is compared with those of their integer order designs, i.e., 2-DOF PID controllers, and with the traditional PID controllers. In order to show effectiveness of proposed scheme, the robustness testing is carried out for model uncertainties, payload variations with time, external disturbance and random noise. Numerical simulation results indicate that the 2-DOF FOPID controllers are superior to their integer order counterparts and the traditional PID controllers. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Optimal Digital Controller Design for a Servo Motor Taking Account of Intersample Behavior

NASA Astrophysics Data System (ADS)

Akiyoshi, Tatsuro; Imai, Jun; Funabiki, Shigeyuki

A continuous-time plant with discretized continuous-time controller do not yield stability if the sampling rate is lower than some certain level. Thus far, high functioning electronic control has made use of high cost hardwares which are needed to implement discretized continuous-time controllers, while low cost hardwares generally do not have high enough sampling rate. This technical note presents results comparing performance indices with and without intersample behavior, and some answer to the question how a low specification device can control a plant effectively. We consider a machine simulating wafer handling robots at semiconductor factories, which is an electromechanical system driven by a direct drive motor. We illustrate controller design for the robot with and without intersample behavior, and simulations and experimental results by using these controllers. Taking intersample behavior into account proves to be effective to make control performance better and enables it to choose relatively long sampling period. By controller design via performance index with intersample behavior, we can cope with situation where short enough sampling period may not be employed, and freedom of controller design might be widened especially on choice of sampling period.

Oral health status and academic performance among Ohio third-graders, 2009-2010.

PubMed

Detty, Amber M R; Oza-Frank, Reena

2014-01-01

Although recent literature indicated an association between dental caries and poor academic performance, previous work relied on self-reported measures. This analysis sought to determine the association between academic performance and untreated dental caries (tooth decay) using objective measures, controlling for school-level characteristics. School-level untreated caries prevalence was estimated from a 2009-2010 oral health survey of Ohio third-graders. Prevalence estimates were combined with school-level academic performance and other school characteristics obtained from the Ohio Department of Education. Linear regression models were developed as a result of bivariate testing, and final models were stratified based upon the presence of a school-based dental sealant program (SBSP). Preliminary bivariate analysis indicated a significant relationship between untreated caries and academic performance, which was more pronounced at schools with an SBSP. After controlling for other school characteristics, the prevalence of untreated caries was found to be a significant predictor of academic performance at schools without an SBSP (P=0.001) but not at schools with an SBSP (P=0.833). The results suggest the association between untreated caries and academic performance may be affected by the presence of a school-based oral health program. Further research focused on oral health and academic performance should consider the presence and/or availability of these programs. © 2014 American Association of Public Health Dentistry.

Emotional reactivity and awareness of task performance in Alzheimer's disease.

PubMed

Mograbi, Daniel C; Brown, Richard G; Salas, Christian; Morris, Robin G

2012-07-01

Lack of awareness about performance in tasks is a common feature of Alzheimer's disease. Nevertheless, clinical anecdotes have suggested that patients may show emotional or behavioural responses to the experience of failure despite reporting limited awareness, an aspect which has been little explored experimentally. The current study investigated emotional reactions to success or failure in tasks despite unawareness of performance in Alzheimer's disease. For this purpose, novel computerised tasks which expose participants to systematic success or failure were used in a group of Alzheimer's disease patients (n=23) and age-matched controls (n=21). Two experiments, the first with reaction time tasks and the second with memory tasks, were carried out, and in each experiment two parallel tasks were used, one in a success condition and one in a failure condition. Awareness of performance was measured comparing participant estimations of performance with actual performance. Emotional reactivity was assessed with a self-report questionnaire and rating of filmed facial expressions. In both experiments the results indicated that, relative to controls, Alzheimer's disease patients exhibited impaired awareness of performance, but comparable differential reactivity to failure relative to success tasks, both in terms of self-report and facial expressions. This suggests that affective valence of failure experience is processed despite unawareness of task performance, which might indicate implicit processing of information in neural pathways bypassing awareness. Copyright © 2012 Elsevier Ltd. All rights reserved.

Comparison between sEMG and force as control interfaces to support planar arm movements in adults with Duchenne: a feasibility study.

PubMed

Lobo-Prat, Joan; Nizamis, Kostas; Janssen, Mariska M H P; Keemink, Arvid Q L; Veltink, Peter H; Koopman, Bart F J M; Stienen, Arno H A

2017-07-12

Adults with Duchenne muscular dystrophy (DMD) can benefit from devices that actively support their arm function. A critical component of such devices is the control interface as it is responsible for the human-machine interaction. Our previous work indicated that surface electromyography (sEMG) and force-based control with active gravity and joint-stiffness compensation were feasible solutions for the support of elbow movements (one degree of freedom). In this paper, we extend the evaluation of sEMG- and force-based control interfaces to simultaneous and proportional control of planar arm movements (two degrees of freedom). Three men with DMD (18-23 years-old) with different levels of arm function (i.e. Brooke scores of 4, 5 and 6) performed a series of line-tracing tasks over a tabletop surface using an experimental active arm support. The arm movements were controlled using three control methods: sEMG-based control, force-based control with stiffness compensation (FSC), and force-based control with no compensation (FNC). The movement performance was evaluated in terms of percentage of task completion, tracing error, smoothness and speed. For subject S1 (Brooke 4) FNC was the preferred method and performed better than FSC and sEMG. FNC was not usable for subject S2 (Brooke 5) and S3 (Brooke 6). Subject S2 presented significantly lower movement speed with sEMG than with FSC, yet he preferred sEMG since FSC was perceived to be too fatiguing. Subject S3 could not successfully use neither of the two force-based control methods, while with sEMG he could reach almost his entire workspace. Movement performance and subjective preference of the three control methods differed with the level of arm function of the participants. Our results indicate that all three control methods have to be considered in real applications, as they present complementary advantages and disadvantages. The fact that the two weaker subjects (S2 and S3) experienced the force-based control interfaces as fatiguing suggests that sEMG-based control interfaces could be a better solution for adults with DMD. Yet force-based control interfaces can be a better alternative for those cases in which voluntary forces are higher than the stiffness forces of the arms.

Fire danger index efficiency as a function of fuel moisture and fire behavior.

PubMed

Torres, Fillipe Tamiozzo Pereira; Romeiro, Joyce Machado Nunes; Santos, Ana Carolina de Albuquerque; de Oliveira Neto, Ricardo Rodrigues; Lima, Gumercindo Souza; Zanuncio, José Cola

2018-08-01

Assessment of the performance of forest fire hazard indices is important for prevention and management strategies, such as planning prescribed burnings, public notifications and firefighting resource allocation. The objective of this study was to evaluate the performance of fire hazard indices considering fire behavior variables and susceptibility expressed by the moisture of combustible material. Controlled burns were carried out at different times and information related to meteorological conditions, characteristics of combustible material and fire behavior variables were recorded. All variables analyzed (fire behavior and fuel moisture content) can be explained by the prediction indices. The Brazilian EVAP/P showed the best performance, both at predicting moisture content of the fuel material and fire behavior variables, and the Canadian system showed the best performance to predicting the rate of spread. The coherence of the correlations between the indices and the variables analyzed makes the methodology, which can be applied anywhere, important for decision-making in regions with no records or with only unreliable forest fire data. Copyright © 2018 Elsevier B.V. All rights reserved.

Field testing of tele-operation versus shared and traded control for military assets: an evaluation involving real-time embedded simulation and soldier assessment

NASA Astrophysics Data System (ADS)

Metcalfe, Jason S.; Alban, Jillyn; Cosenzo, Keryl; Johnson, Tony; Capstick, Erin

2010-04-01

Those applying autonomous technologies to military systems strive to enhance human-robot and robot-robot performance. Beyond performance, the military must be concerned with local area security. Characterized as "secure mobility", military systems must enable safe and effective terrain traversal concurrent with maintenance of situational awareness (SA). One approach to interleaving these objectives is supervisory control, with popular options being shared and traded control. Yet, with the scale and expense of military assets, common technical issues such as transition time and safeguarding become critical; especially as they interact with Soldier capabilities. Study is required to enable selection of control methods that optimize Soldier-system performance while safeguarding both individually. The current report describes a study utilizing experimental military vehicles and simulation systems enabling teleoperation and supervisory control. Automated triggering of SA demands was interspersed with a set of challenging driving maneuvers in a 'teleoperation-like' context to examine the influence of supervisory control on Soldier-system performance. Results indicated that direct application of supervisory control, while beneficial under particular demands, requires continued development to be perceived by Soldiers as useful. Future efforts should more tightly couple the information exchanged between the Soldier and system to overcome current challenges not addressed by standard control methods.

An analytical and experimental investigation of active structural acoustic control of noise transmission through double panel systems

NASA Astrophysics Data System (ADS)

Carneal, James P.; Fuller, Chris R.

2004-05-01

An analytical and experimental investigation of active control of sound transmission through double panel systems has been performed. The technique used was active structural acoustic control (ASAC) where the control inputs, in the form of piezoelectric actuators, were applied to the structure while the radiating pressure field was minimized. Results verify earlier experimental investigations and indicate the application of control inputs to the radiating panel of the double panel system resulted in greater transmission loss (TL) due to its direct effect on the nature of the structural-acoustic (or radiation) coupling between the radiating panel and the receiving acoustic space. Increased control performance was seen in a double panel system consisting of a stiffer radiating panel due to its lower modal density and also as a result of better impedance matching between the piezoelectric actuator and the radiating plate. In general the results validate the ASAC approach for double panel systems, demonstrating that it is possible to take advantage of double panel system passive behavior to enhance control performance, and provide design guidelines.

A spacecraft integrated power/attitude control system

NASA Technical Reports Server (NTRS)

Keckler, C. R.; Jacobs, K. L.

1974-01-01

A study to determine the viability and application of a system capable of performing the dual function of power storage/generation and attitude control has been conducted. Results from the study indicate that an integrated power/attitude control system (IPACS) can satisfy future mission requirements while providing significant savings in weight, volume, and cost over conventional systems. A failure-mode configuration of an IPACS was applied to a shuttle-launched RAM free-flyer and simulated using make-do hardware linked to a hybrid computer. Data from the simulation runs indicate that control interactions resulting from heavy power demands have minimal effect on system control effectiveness. The system was shown to be capable of meeting the stringent pointing requirements of 1 arc-second while operating under the influence of an orbital disturbance environment and during periods of momentum variations imposed by energy transfer requirements.

Indicator-based systems of performance management in the National Health Service: a comparison of the perceptions of local- and national-level managers.

PubMed

Jones, G T

2000-02-01

Historically, the UK Government has policed the use of National Health Service (NHS) resources through the centralization of control. With the majority of resource-draining decisions being taken by clinicians, however, professional financial accountability is becoming more important within the NHS management structure. Variations in clinical performance can be monitored through the use of performance indicators, although these are not without their problems. The use of league tables of such indicators in the national press is now infamous and there is much anecdotal evidence about the intraorganizational conflict arising from the use of such tables. A questionnaire survey and interview study of clinical directors, clinical service directors and business managers in several Scottish NHS Trusts was undertaken to ascertain the perceptions of local-level managers on the issue of performance indicators. Interviews were also carried out with a number of personnel in the Scottish Office Department of Economics and Information, the Division of Health Gain and the Finance Directorate. This paper explores the differences between the perceptions of the managers at these two levels of the NHS with regards to issues of performance measurement, intraorganizational conflict and corporate vision.

Integrated guidance and control for microsatellite real-time automated proximity operations

NASA Astrophysics Data System (ADS)

Chen, Ying; He, Zhen; Zhou, Ding; Yu, Zhenhua; Li, Shunli

2018-07-01

This paper investigates the trajectory planning and control of autonomous spacecraft proximity operations with impulsive dynamics. A new integrated guidance and control scheme is developed to perform automated close-range rendezvous for underactuated microsatellites. To efficiently prevent collision, a modified RRT* trajectory planning algorithm is proposed under this context. Several engineering constraints such as collision avoidance, plume impingement, field of view and control feasibility are considered simultaneously. Then, the feedback controller that employs a turn-burn-turn strategy with a combined impulsive orbital control and finite-time attitude control is designed to ensure the implementation of planned trajectory. Finally, the performance of trajectory planner and controller are evaluated through numerical tests. Simulation results indicate the real-time implementability of the proposed integrated guidance and control scheme with position control error less than 0.5 m and velocity control error less than 0.05 m/s. Consequently, the proposed scheme offers the potential for wide applications, such as on-orbit maintenance, space surveillance and debris removal.

Does daily nurse staffing match ward workload variability? Three hospitals' experiences.

PubMed

Gabbay, Uri; Bukchin, Michael

2009-01-01

Nurse shortage and rising healthcare resource burdens mean that appropriate workforce use is imperative. This paper aims to evaluate whether daily nursing staffing meets ward workload needs. Nurse attendance and daily nurses' workload capacity in three hospitals were evaluated. Statistical process control was used to evaluate intra-ward nurse workload capacity and day-to-day variations. Statistical process control is a statistics-based method for process monitoring that uses charts with predefined target measure and control limits. Standardization was performed for inter-ward analysis by converting ward-specific crude measures to ward-specific relative measures by dividing observed/expected. Two charts: acceptable and tolerable daily nurse workload intensity, were defined. Appropriate staffing indicators were defined as those exceeding predefined rates within acceptable and tolerable limits (50 percent and 80 percent respectively). A total of 42 percent of the overall days fell within acceptable control limits and 71 percent within tolerable control limits. Appropriate staffing indicators were met in only 33 percent of wards regarding acceptable nurse workload intensity and in only 45 percent of wards regarding tolerable workloads. The study work did not differentiate crude nurse attendance and it did not take into account patient severity since crude bed occupancy was used. Double statistical process control charts and certain staffing indicators were used, which is open to debate. Wards that met appropriate staffing indicators prove the method's feasibility. Wards that did not meet appropriate staffing indicators prove the importance and the need for process evaluations and monitoring. Methods presented for monitoring daily staffing appropriateness are simple to implement either for intra-ward day-to-day variation by using nurse workload capacity statistical process control charts or for inter-ward evaluation using standardized measure of nurse workload intensity. The real challenge will be to develop planning systems and implement corrective interventions such as dynamic and flexible daily staffing, which will face difficulties and barriers. The paper fulfils the need for workforce utilization evaluation. A simple method using available data for daily staffing appropriateness evaluation, which is easy to implement and operate, is presented. The statistical process control method enables intra-ward evaluation, while standardization by converting crude into relative measures enables inter-ward analysis. The staffing indicator definitions enable performance evaluation. This original study uses statistical process control to develop simple standardization methods and applies straightforward statistical tools. This method is not limited to crude measures, rather it uses weighted workload measures such as nursing acuity or weighted nurse level (i.e. grade/band).

Time management training and perceived control of time at work.

PubMed

Häfner, Alexander; Stock, Armin

2010-01-01

The purpose of the present study was to examine the effects of time management training, which was based on psychological theory and research, on perceived control of time, perceived stress, and performance at work. The authors randomly assigned 71 employees to a training group (n = 35) or a waiting-list control group (n = 36). As hypothesized, time management training led to an increase in perceived control of time and a decrease in perceived stress. Time management training had no impact on different performance indicators. In particular, the authors explored the use and the perceived usefulness of the techniques taught. Participants judged the taught techniques as useful, but there were large differences concerning the actual use of the various techniques.

A receding horizon sliding control approach for electric powertrains with backlash and flexible half-shafts

NASA Astrophysics Data System (ADS)

Li, Yutong; Hansen, Andreas; Karl Hedrick, J.; Zhang, Junzhi

2017-12-01

Active control of electric powertrains is challenging, due to the fact that backlash and structural flexibility in transmission components can cause severe performance degradation or even instability of the control system. Furthermore, high impact forces in transmissions reduce driving comfort and possibly lead to damage of the mechanical elements in contact. In this paper, a nonlinear electric powertrain is modelled as a piecewise affine (PWA) system. The novel receding horizon sliding control (RHSC) idea is extended to constrained PWA systems and utilised to systematically address the active control problem for electric powertrains. Simulations are conducted in Matlab/Simulink in conjunction with the high fidelity Carsim software. RHSC shows superior jerk suppression and target wheel speed tracking performance as well as reduced computational cost over classical model predictive control (MPC). This indicates the newly proposed RHSC is an effective method to address the active control problem for electric powertrains.

Exploring Improvement Science in Education: Promoting College Access in Fresno Unified School District

ERIC Educational Resources Information Center

Aguilar, Jorge; Nayfack, Michelle; Bush-Mecenas, Susan

2017-01-01

California's Local Control Funding Formula (LCFF) requires districts to report multiple measures of student performance that reflect success in the goal of preparing students for college, career, and citizenship. As they engage in the Local Control Accountability Plan (LCAP) process, they are expected to use state and local indicator data from…

Differences in Soccer Kick Kinematics between Blind Players and Controls

ERIC Educational Resources Information Center

Giagazoglou, Paraskevi; Katis, Athanasios; Kellis, Eleftherios; Natsikas, Christos

2011-01-01

The purpose of the current study was to examine the kinematic differences during instep soccer kicks between players who were blind and sighted controls. Eleven male soccer players who were blind and nine male sighted performed instep kicks under static and dynamic conditions. The results indicated significantly higher (p less than 0.05) ball…

PID temperature controller in pig nursery: improvements in performance, thermal comfort, and electricity use.

PubMed

de Souza Granja Barros, Juliana; Rossi, Luiz Antonio; Sartor, Karina

2016-08-01

The use of smarter temperature control technologies in heating systems can optimize the use of electric power and performance of piglets. Two control technologies of a resistive heating system were assessed in a pig nursery: a PID (proportional, integral, and derivative) controller and a thermostat. The systems were evaluated regarding thermal environment, piglet performance, and use of electric power for 99 days. The heating system with PID controller improved the thermal environment conditions and was significantly (P < 0.001) more efficient in terms of electricity use to produce 1 kg of body weight (2.88 kWh kg(-1)), specific cost (0.75 R$ kg(-1)), weight gain (7.3 kg), daily weight gain (0.21 kg day(-1)), and feed conversion (1.71) than the system with thermostat (3.98 kWh kg(-1); 1.03 R$ kg(-1); 5.2 kg; 0.15 kg day(-1), and 2.62, respectively). The results indicate that the PID-controlled heating system is more efficient in electricity use and provides better conditions for thermal comfort and animal performance than heating with thermostat.

Performance seeking control excitation mode

NASA Technical Reports Server (NTRS)

Schkolnik, Gerard

1995-01-01

Flight testing of the performance seeking control (PSC) excitation mode was successfully completed at NASA Dryden on the F-15 highly integrated digital electronic control (HIDEC) aircraft. Although the excitation mode was not one of the original objectives of the PSC program, it was rapidly prototyped and implemented into the architecture of the PSC algorithm, allowing valuable and timely research data to be gathered. The primary flight test objective was to investigate the feasibility of a future measurement-based performance optimization algorithm. This future algorithm, called AdAPT, which stands for adaptive aircraft performance technology, generates and applies excitation inputs to selected control effectors. Fourier transformations are used to convert measured response and control effector data into frequency domain models which are mapped into state space models using multiterm frequency matching. Formal optimization principles are applied to produce an integrated, performance optimal effector suite. The key technical challenge of the measurement-based approach is the identification of the gradient of the performance index to the selected control effector. This concern was addressed by the excitation mode flight test. The AdAPT feasibility study utilized the PSC excitation mode to apply separate sinusoidal excitation trims to the controls - one aircraft, inlet first ramp (cowl), and one engine, throat area. Aircraft control and response data were recorded using on-board instrumentation and analyzed post-flight. Sensor noise characteristics, axial acceleration performance gradients, and repeatability were determined. Results were compared to pilot comments to assess the ride quality. Flight test results indicate that performance gradients were identified at all flight conditions, sensor noise levels were acceptable at the frequencies of interest, and excitations were generally not sensed by the pilot.

A Contingency in the Rosetta Reaction Control System: Alternative Cruise Trajectory Strategies to Cope with Degraded Delta-V Resources

NASA Technical Reports Server (NTRS)

Bauske, Rainer; Companys, Vincente

2007-01-01

Since August 2006 a pressure transducer of the Rosetta Reaction Control System (RCS) shows anomalous telemetries indicating a possible leak in a pressurant line. The future operation mode of the RCS may be affected by this problem, resulting in performance degradation. The current propellant budget and its future evolution are evaluated to show the possible states w.r.t. the required mission delta-V. Alternative cruise trajectory strategies are analyzed, providing delta-V savings, to compensate for the expected performance loss of the RCS.

Amygdala volume and verbal memory performance in schizophrenia and bipolar disorder.

PubMed

Killgore, William D S; Rosso, Isabelle M; Gruber, Staci A; Yurgelun-Todd, Deborah A

2009-03-01

To clarify the relationship between amygdala-hippocampal volume and cognitive performance in schizophrenia and bipolar disorder. Abnormalities of the amygdala-hippocampal complex and memory deficits have been reported in both schizophrenia and bipolar illness. We examined memory performance and its relationship to the volumes of the whole brain, lateral ventricles, hippocampus, and amygdala using morphometric magnetic resonance imaging in 19 patients with schizophrenia, 11 bipolar patients, and 20 healthy controls. Schizophrenia patients performed more poorly than bipolar patients and controls on indices of memory functioning, whereas patients with bipolar disorder showed milder impairments relative to controls. The schizophrenia group showed reduced total cerebral volume and enlarged ventricles relative to controls, but no group differences were found for amygdala or hippocampal volume. Left amygdala volume was predictive of memory performance in both groups, correlating positively with better immediate and delayed verbal memory for bipolar patients and negatively with immediate and delayed verbal recall for schizophrenia patients. Amygdala volume was unrelated to memory performance in healthy subjects. Schizophrenia and bipolar disorder both seem to be associated with anomalous and differential limbic volume-function relationships, such that the amygdala may facilitate hippocampal-dependent memory processes in bipolar disorder but impair these same processes in schizophrenia.

Perpetual factors involved in performance of air traffic controllers using a microwave landing system

NASA Technical Reports Server (NTRS)

Gershzohn, G.

1978-01-01

The task involved the control of two simulated aircraft targets per trial, in a 37.0 -km radius terminal area, by means of conventional radar vectoring and/or speed control. The goal was to insure that the two targets crossed the Missed Approach Point (MAP) at the runway threshold exactly 60 sec apart. The effects on controller performance of the MLS configuration under wind and no-wind conditions were examined. The data for mean separation time between targets at the MAP and the range about that mean were analyzed by appropriate analyses of variance. Significant effects were found for mean separation times as a result of the configuration of the MLS and for interaction between the configuration and wind conditions. The analysis of variance for range indicated significantly poorer performance under the wind condition. These findings are believed to be a result of certain perceptual factors involved in radar air traffic control (ATC) using the MLS with separation of targets in time.

Advanced Running Performance by Genetic Predisposition in Male Dummerstorf Marathon Mice (DUhTP) Reveals Higher Sterol Regulatory Element-Binding Protein (SREBP) Related mRNA Expression in the Liver and Higher Serum Levels of Progesterone

PubMed Central

Brenmoehl, Julia; Walz, Christina; Ponsuksili, Siriluck; Schwerin, Manfred; Fuellen, Georg; Hoeflich, Andreas

2016-01-01

Long-term-selected DUhTP mice represent a non-inbred model for inborn physical high-performance without previous training. Abundance of hepatic mRNA in 70-day male DUhTP and control mice was analyzed using the Affymetrix mouse array 430A 2.0. Differential expression analysis with PLIER corrected data was performed using AltAnalyze. Searching for over-representation in biochemical pathways revealed cholesterol metabolism being most prominently affected in DUhTP compared to unselected control mice. Furthermore, pathway analysis by AltAnalyze plus PathVisio indicated significant induction of glycolysis, fatty acid synthesis and cholesterol biosynthesis in the liver of DUhTP mice versus unselected control mice. In contrast, gluconeogenesis was partially inactivated as judged from the analysis of hepatic mRNA transcript abundance in DUhTP mice. Analysis of mRNA transcripts related to steroid hormone metabolism inferred elevated synthesis of progesterone and reduced levels of sex steroids. Abundance of steroid delta isomerase-5 mRNA (Hsd3b5, FC 4.97) was increased and steroid 17-alpha-monooxygenase mRNA (Cyp17a1, FC -11.6) was massively diminished in the liver of DUhTP mice. Assessment of steroid profiles by LC-MS revealed increased levels of progesterone and decreased levels of sex steroids in serum from DUhTP mice versus controls. Analysis of hepatic mRNA transcript abundance indicates that sterol regulatory element-binding protein-1 (SREBP-1) may play a major role in metabolic pathway activation in the marathon mouse model DUhTP. Thus, results from bioinformatics modeling of hepatic mRNA transcript abundance correlated with direct steroid analysis by mass spectrometry and further indicated functions of SREBP-1 and steroid hormones for endurance performance in DUhTP mice. PMID:26799318

Effects of Flexitime on Sick Leave, Vacation Leave, Anxiety, Performance, and Satisfaction in a Library Setting.

ERIC Educational Resources Information Center

Saunders, Carol Stoak; Saunders, Russell

1985-01-01

Results of study using pretest and posttest control group design in public university library setting to study impact of flexitime indicate that: satisfaction with promotions decreased with significant effect, sick leaves decreased, average length of vacation leaves increased, and results were mixed on performance and approached significance for…

Pilot performance in zero-visibility precision approach. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Ephrath, A. R.

1975-01-01

The pilot's short-term decisions regarding performance assessment and failure monitoring is examined. The performance of airline pilots who flew simulated zero-visibility landing approaches is reported. Results indicate that the pilot's mode of participation in the control task has a strong effect on his workload, the induced workload being lowest when the pilot acts as a monitor during a coupled approach and highest when the pilot is an active element in the control loop. A marked increase in workload at altitudes below 500 ft. is documented at all participation modes; this increase is inversely related to distance-to-go. The participation mode is shown to have a dominant effect on failure-detection performance, with a failure in a monitored (coupled) axis being detected faster than a comparable failure in a manually-controlled axis. Touchdown performance is also documented. It is concluded that the conventional instrument panel and its associated displays are inadequate for zero-visibility operations in the final phases of the landing approach.

Exercise improves behavioral, neurocognitive, and scholastic performance in children with attention-deficit/hyperactivity disorder.

PubMed

Pontifex, Matthew B; Saliba, Brian J; Raine, Lauren B; Picchietti, Daniel L; Hillman, Charles H

2013-03-01

To examine the effect of a single bout of moderate-intensity aerobic exercise on preadolescent children with attention-deficit/hyperactivity disorder (ADHD) using objective measures of attention, brain neurophysiology, and academic performance. Using a within-participants design, task performance and event-related brain potentials were assessed while participants performed an attentional-control task following a bout of exercise or seated reading during 2 separate, counterbalanced sessions. Following a single 20-minute bout of exercise, both children with ADHD and healthy match control children exhibited greater response accuracy and stimulus-related processing, with the children with ADHD also exhibiting selective enhancements in regulatory processes, compared with after a similar duration of seated reading. In addition, greater performance in the areas of reading and arithmetic were observed following exercise in both groups. These findings indicate that single bouts of moderately intense aerobic exercise may have positive implications for aspects of neurocognitive function and inhibitory control in children with ADHD. Copyright © 2013 Mosby, Inc. All rights reserved.

Parenting Styles and Adolescents’ School Adjustment: Investigating the Mediating Role of Achievement Goals within the 2 × 2 Framework

PubMed Central

Xiang, Shiyuan; Liu, Yan; Bai, Lu

2017-01-01

This study examines the multiple mediating roles of achievement goals based on a 2 × 2 framework of the relationships between parenting styles and adolescents’ school adjustment. The study sample included 1061 Chinese adolescent students (50.4% girls) between the ages of 12 and 19, who completed questionnaires regarding parenting styles (parental autonomy support and psychological control), achievement goals (mastery approach, mastery avoidance, performance approach, and performance avoidance goals) and school adjustment variables (emotion, students’ life satisfaction, school self-esteem, problem behavior, academic achievement, and self-determination in school). A structural equation modeling (SEM) approach was used to test our hypotheses. The results indicated that parental autonomy support was associated with adolescents’ school adjustment in an adaptive manner, both directly and through its positive relationship with both mastery and performance approach goals; however, parental psychological control was associated with adolescents’ school adjustment in a maladaptive manner, both directly and through its positive relationship with both mastery and performance avoidance goals. In addition, the results indicated that mastery avoidance goals suppressed the relationship between parental autonomy support and adolescents’ school adjustment, and performance approach goals suppressed the relationship between this adjustment and parental psychological control. These findings extend the limited literature regarding the 2 × 2 framework of achievement goals and enable us to evidence the mediating and suppressing effects of achievement goals. This study highlights the importance of parenting in adolescents’ school adjustment through the cultivation of different achievement goals. PMID:29085321

Parenting Styles and Adolescents' School Adjustment: Investigating the Mediating Role of Achievement Goals within the 2 × 2 Framework.

PubMed

Xiang, Shiyuan; Liu, Yan; Bai, Lu

2017-01-01

This study examines the multiple mediating roles of achievement goals based on a 2 × 2 framework of the relationships between parenting styles and adolescents' school adjustment. The study sample included 1061 Chinese adolescent students (50.4% girls) between the ages of 12 and 19, who completed questionnaires regarding parenting styles (parental autonomy support and psychological control), achievement goals (mastery approach, mastery avoidance, performance approach, and performance avoidance goals) and school adjustment variables (emotion, students' life satisfaction, school self-esteem, problem behavior, academic achievement, and self-determination in school). A structural equation modeling (SEM) approach was used to test our hypotheses. The results indicated that parental autonomy support was associated with adolescents' school adjustment in an adaptive manner, both directly and through its positive relationship with both mastery and performance approach goals; however, parental psychological control was associated with adolescents' school adjustment in a maladaptive manner, both directly and through its positive relationship with both mastery and performance avoidance goals. In addition, the results indicated that mastery avoidance goals suppressed the relationship between parental autonomy support and adolescents' school adjustment, and performance approach goals suppressed the relationship between this adjustment and parental psychological control. These findings extend the limited literature regarding the 2 × 2 framework of achievement goals and enable us to evidence the mediating and suppressing effects of achievement goals. This study highlights the importance of parenting in adolescents' school adjustment through the cultivation of different achievement goals.

Monitoring and control requirement definition study for Dispersed Storage and Generation (DSG), volume 1

NASA Technical Reports Server (NTRS)

1980-01-01

Twenty-four functional requirements were prepared under six categories and serve to indicate how to integrate dispersed storage generation (DSG) systems with the distribution and other portions of the electric utility system. Results indicate that there are no fundamental technical obstacles to prevent the connection of dispersed storage and generation to the distribution system. However, a communication system of some sophistication is required to integrate the distribution system and the dispersed generation sources for effective control. The large-size span of generators from 10 KW to 30 MW means that a variety of remote monitoring and control may be required. Increased effort is required to develop demonstration equipment to perform the DSG monitoring and control functions and to acquire experience with this equipment in the utility distribution environment.

Positive and Negative Affect and Adolescent Adjustment: Moderation Effects of Prefrontal Functioning.

PubMed

Brieant, Alexis; Holmes, Christopher J; Maciejewski, Dominique; Lee, Jacob; Deater-Deckard, Kirby; King-Casas, Brooks; Kim-Spoon, Jungmeen

2018-03-01

We examined whether cognitive control moderates the effects of emotion on adolescent internalizing and externalizing symptomatology in a longitudinal study of 138 adolescents. Self-reported positive affect (PA) and negative affect and behavioral and neural indicators of cognitive control, indexed by performance and prefrontal hemodynamic response during a cognitive interference task, were collected at Time 1. Self-reported internalizing and externalizing symptomatology were collected at Time 1 and Time 2 (1 year later). Results indicated that higher PA predicted decreases in externalizing symptomatology, but only for adolescents with poor neural cognitive control. No moderation effects were found for behavioral cognitive control. Findings imply the beneficial effects of PA on the development of externalizing problems among adolescents with poor prefrontal functioning. © 2018 Society for Research on Adolescence.

Experience and Grouping Effects when Handling Non-Normal Situations

NASA Technical Reports Server (NTRS)

Trujillo, Anna C.

2004-01-01

Currently, most of the displays in control rooms can be categorized as status, alerts/procedures, or control screens. With the advent and use of CRTs and the associated computing power available to compute and display information, it is now possible to combine these different elements of information and control onto a single display. An experiment was conducted to determine which, if any, of these functions should be collocated in order to better handle simple anticipated non-normal system events. The results indicated that there are performance benefits and subject preferences to combining all the information onto one screen or combining the status and alert/procedure information onto one screen and placing the controls in another area. The results indicated that operators quickly modify their display preferences to the display configuration most recently used.

Bilateral force reflection for teleoperators with masters and slaves with dissimilar and possibly redundant kinematics

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

Jansen, J.F.; Babcock, S.M.

1989-11-01

Several bilateral control techniques and methods for exploiting redundant slaves are investigated as a part of research to develop and analyze bilateral, force-reflecting control methodologies for teleoperator systems with kinematic dissimilar masters and slaves. The study indicates that, with force/torque sensing at the wrist, and an impedance type of controller with the appropriate joint compensation, a significant improvement in performance and controllability of a teleoperator system can be achieved. 32 refs., 6 figs., 2 tabs.

Solving the optimal attention allocation problem in manual control

NASA Technical Reports Server (NTRS)

Kleinman, D. L.

1976-01-01

Within the context of the optimal control model of human response, analytic expressions for the gradients of closed-loop performance metrics with respect to human operator attention allocation are derived. These derivatives serve as the basis for a gradient algorithm that determines the optimal attention that a human should allocate among several display indicators in a steady-state manual control task. Application of the human modeling techniques are made to study the hover control task for a CH-46 VTOL flight tested by NASA.

New type of measuring and intelligent instrument for curing tobacco

NASA Astrophysics Data System (ADS)

Yi, Chui-Jie; Huang, Xieqing; Chen, Tianning; Xia, Hong

1993-09-01

A new type of measuring intelligent instrument for cured tobacco is presented in this paper. Based on fuzzy linguistic control principles the instrument is used to controlling the temperature and humidity during cured tobacco taking 803 1 singlechip computer as a center controller. By using methods of fuzzy weighted factors the cross coupling in curing procedures is decoupled. Results that the instrument has producted indicate the fuzzy controller in the instrument has perfect performance for process of cured tobacco as shown in figure

The impact of angry rumination on anger-primed cognitive control.

PubMed

Lievaart, Marien; Huijding, Jorg; van der Veen, Frederik M; Hovens, Johannes E; Franken, Ingmar H A

2017-03-01

Recent research suggests that angry rumination augments aggressive behavior by depleting self-control resources. Yet, few studies have been conducted to empirically support this proposal. In the present study, we therefore sought to investigate the effects of angry rumination, relative to distraction, on self-reported anger and a behavioral indicator of self-control. Seventy-two participants recalled and imagined an anger-inducing autobiographical memory and were instructed to engage in either angry rumination (n = 37) or distraction (n = 35). Following these emotion regulation instructions, participants performed an affective Go/NoGo task in order to assess behavioral self-control along with several questionnaires to assess anger related constructs. As expected, results revealed that angry rumination augmented anger, whereas anger decreased in the distraction condition. Contrary to predictions, we found no differences between both groups in performance on the affective Go/NoGo task. A potential limitation is we instructed our participants on how to regulate their emotions rather than letting angry rumination occur spontaneously. The findings indicate that whereas angry rumination results in heightened anger, it does not seem to result in lower self-control as measured with a behavioral task that requires cognitive control. More research is needed to test the boundary conditions regarding the role of self-control in understanding rumination-induced aggression. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthetic Vision Systems in GA Cockpit-Evaluation of Basic Maneuvers Performed by Low Time GA Pilots During Transition from VMC to IMC

NASA Technical Reports Server (NTRS)

Takallu, M. A.; Wong, D. T.; Uenking, M. D.

2002-01-01

An experimental investigation was conducted to study the effectiveness of modern flight displays in general aviation cockpits for mitigating Low Visibility Loss of Control and the Controlled Flight Into Terrain accidents. A total of 18 General Aviation (GA) pilots with private pilot, single engine land rating, with no additional instrument training beyond private pilot license requirements, were recruited to evaluate three different display concepts in a fixed-based flight simulator at the NASA Langley Research Center's General Aviation Work Station. Evaluation pilots were asked to continue flight from Visual Meteorological Conditions (VMC) into Instrument Meteorological Conditions (IMC) while performing a series of 4 basic precision maneuvers. During the experiment, relevant pilot/vehicle performance variables, pilot control inputs and physiological data were recorded. Human factors questionnaires and interviews were administered after each scenario. Qualitative and quantitative data have been analyzed and the results are presented here. Pilot performance deviations from the established target values (errors) were computed and compared with the FAA Practical Test Standards. Results of the quantitative data indicate that evaluation pilots committed substantially fewer errors when using the Synthetic Vision Systems (SVS) displays than when they were using conventional instruments. Results of the qualitative data indicate that evaluation pilots perceived themselves to have a much higher level of situation awareness while using the SVS display concept.

Music psychopathology. V. Objective features of instrumental performance and psychopathology.

PubMed

Steinberg, R; Fani, M; Raith, L

1992-01-01

Mental disease systematically impairs musical expression according to nosologic classification. This was demonstrated with a polarity profile of the instrumental performances of 60 inpatients and 14 controls matched for musical aptitude. Objective performance characteristics such as irregularities and playing faults were analyzed too. No meaningful correlation between these features and psychopathology resulted. This indicates that even in severe psychopathologic alterations performance features, which depend mainly on education and actual training, are not altered in a systematic manner, in contrast to expressive qualities.

OH-13H Gross Weight Increase/XM-1 Armament Kit Performance Test

DTIC Science & Technology

1963-06-01

in hovering performance beyond thai obtained in the Air Force Performance lest of the 0H-I3H, de - scribed in MFFTC-TR...The airspeed schedule used during the climbs was the same as that developed during the OH-!3H performance test de - sci iüed in AFrrC-TR-57-12...siight de - crease in control response was indicated by a small amount of feedback through the unboosted collective stick. Level Flight

Children and adolescents' performance on a medium-length/nonsemantic word-list test.

PubMed

Flores-Lázaro, Julio César; Salgado Soruco, María Alejandra; Stepanov, Igor I

2017-01-01

Word-list learning tasks are among the most important and frequently used tests for declarative memory evaluation. For example, the California Verbal Learning Test-Children's Version (CVLT-C) and Rey Auditory Verbal Learning Test provide important information about different cognitive-neuropsychological processes. However, the impact of test length (i.e., number of words) and semantic organization (i.e., type of words) on children's and adolescents' memory performance remains to be clarified, especially during this developmental stage. To explore whether a medium-length non-semantically organized test can produce the typical curvilinear performance that semantically organized tests produce, reflecting executive control, we studied and compared the cognitive performance of normal children and adolescents by utilizing mathematical modeling. The model is based on the first-order system transfer function and has been successfully applied to learning curves for the CVLT-C (15 words, semantically organized paradigm). Results indicate that learning nine semantically unrelated words produces typical curvilinear (executive function) performance in children and younger adolescents and that performance could be effectively analyzed with the mathematical model. This indicates that the exponential increase (curvilinear performance) of correctly learned words does not solely depend on semantic and/or length features. This type of test controls semantic and length effects and may represent complementary tools for executive function evaluation in clinical populations in which semantic and/or length processing are affected.

The relationship of hip muscle performance to leg, ankle and foot injuries: a systematic review.

PubMed

Steinberg, Nili; Dar, Gali; Dunlop, Martin; Gaida, James Edmund

2017-02-01

Hip control affects movement and muscle firing patterns in the leg, ankle and foot, and may contribute to overuse injuries. Muscle performance can be measured as strength, endurance or muscle activation patterns. Our objective was to systematically review whether hip muscle performance is associated with leg, ankle and foot injuries. A structured and comprehensive search of six medical literature databases was combined with forward and backward citation tracking (AMED, CINAHL, EMBASE, Medline, Scopus and SportDiscus). Eligible studies measured hip muscle performance in individuals with musculoskeletal injuries below the tibial tuberosity, using dynamometry or electromyography (EMG). All studies compared an injured group with a control group or compared the injured and non-injured limb in the same individual. Data was extracted from each study independently by two authors. Twenty case-control and four prospective studies (n = 24) met the inclusion criteria. Injury classifications included chronic ankle instability (n = 18), Achilles tendinopathy (n = 2), medial tibial stress syndrome and tibial stress fracture (n = 1), posterior tibial tendon dysfunction (n = 1), and exertional medial tibial pain (n = 2). Eleven of the studies revealed differences in hip muscle performance indicating less strength, delayed onset activation and decreased duration of activation in the injured groups. Two studies found evidence for differences between groups only in some of their measurements. Three out of the four prospective studies revealed that hip muscle performance was not a risk factor for leg, ankle and foot injuries. This review provides limited evidence that hip muscle performance variables are related to leg, ankle and foot injuries. Emerging evidence indicates this might be a result of the injury rather than a contributor to the injury.

Psychiatric epidemiologic study of occupational lead exposure

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

Parkinson, D.K.; Ryan, C.; Bromet, E.J.

1986-02-01

The association of occupational lead exposure with neuropsychiatric functioning was evaluated using data collected in 1982 in eastern Pennsylvania from 288 lead-exposed workers and 181 nonexposed subjects. Both current and cumulative exposure indices were used. After controlling for age, education, and income, few meaningful differences between exposed and control workers were found on either neuropsychologic or psychosocial variables. Dose-response analyses indicated that among lead-exposed workers, cumulative and current exposure were unrelated to neuropsychologic performance. The only meaningful associations occurred between exposure and level of conflict in interpersonal relationships. The results thus give evidence against hypotheses suggesting adverse neuropsychologic effects.

Context Specificity of Post-Error and Post-Conflict Cognitive Control Adjustments

PubMed Central

Forster, Sarah E.; Cho, Raymond Y.

2014-01-01

There has been accumulating evidence that cognitive control can be adaptively regulated by monitoring for processing conflict as an index of online control demands. However, it is not yet known whether top-down control mechanisms respond to processing conflict in a manner specific to the operative task context or confer a more generalized benefit. While previous studies have examined the taskset-specificity of conflict adaptation effects, yielding inconsistent results, control-related performance adjustments following errors have been largely overlooked. This gap in the literature underscores recent debate as to whether post-error performance represents a strategic, control-mediated mechanism or a nonstrategic consequence of attentional orienting. In the present study, evidence of generalized control following both high conflict correct trials and errors was explored in a task-switching paradigm. Conflict adaptation effects were not found to generalize across tasksets, despite a shared response set. In contrast, post-error slowing effects were found to extend to the inactive taskset and were predictive of enhanced post-error accuracy. In addition, post-error performance adjustments were found to persist for several trials and across multiple task switches, a finding inconsistent with attentional orienting accounts of post-error slowing. These findings indicate that error-related control adjustments confer a generalized performance benefit and suggest dissociable mechanisms of post-conflict and post-error control. PMID:24603900

Evaluating National Environmental Sustainability: Performance Measures and Influential Factors for OECD-Member Countries featuring Canadian Performance and Policy Implications

NASA Astrophysics Data System (ADS)

Calbick, Kenneth S.

This research reviews five studies that evaluate national environmental sustainability with composite indices; performs uncertainty and sensitivity analyses of techniques for building a composite index; completes principal components factor analysis to help build subindices measuring waste and pollution, sustainable energy, sustainable food, nature conservation, and sustainable cities (Due to its current importance, the greenhouse gases (GHG) indicator is included individually as another policy measure.); analyses factors that seem to influence performance: climate, population growth, population density, economic output, technological development, industrial structure, energy prices, environmental governance, pollution abatement and control expenditures, and environmental pricing; and explores Canadian policy implications of the results. The techniques to build composite indices include performance indicator selection, missing data treatment, normalisation technique, scale-effect adjustments, weights, and aggregation method. Scale-effect adjustments and normalisation method are significant sources of uncertainty inducing 68% of the observed variation in a country's final rank at the 95% level of confidence. Choice of indicators also introduces substantial variation as well. To compensate for this variation, the current study recommends that a composite index should always be analysed with other policy subindices and individual indicators. Moreover, the connection between population and consumption indicates that per capita scale-effect adjustments should be used for certain indicators. Rather than ranking normalisation, studies should use a method that retains information from the raw indicator values. Multiple regression and cluster analyses indicate economic output, environmental governance, and energy prices are major influential factors, with energy prices the most important. It is statistically significant for five out of seven performance measures at the 95% level of confidence: 37% variance explained on the environmental sustainability performance composite indicator out of 73%, 55% (of 55%) on the waste and pollution subindex, 20% (of 70%) on the sustainable energy subindex, 5% (of 100%) on the sustainable cities subindex, and 55% (of 81%) on the GHG indicator. Energy prices are relevant to Canadian policy; increasing prices could substantially improve Canada's performance. Policy makers should increase energy prices through a carbon pricing strategy that is congruent with the ecological fiscal reform advanced by the National Round Table on the Environment and the Economy. Keywords: sustainable development; composite indices; environmental policy; environmental governance; energy prices; Canada.

[Personality determinants of effectiveness in performing duties by soldiers in active service in the landing-shock brigade].

PubMed

Florkowski, A; Caban, Z; Szczesny, D; Zboralski, K

1996-01-01

After studies in the Brigade the authors identified and qualified personality traits which co-determine effectiveness in performing duties in active service. The efficiency of performing duties is determined by: high emotional resistance, high level of ability to logical conclusion, high level of self-control, low extroversion level, lack of antisocial tendencies. The authors worked out some indications concerning choice and selection for this military formation.

Cognate effects and cognitive control in patients with parallel and differential bilingual aphasia.

PubMed

Van der Linden, Lize; Verreyt, Nele; De Letter, Miet; Hemelsoet, Dimitri; Mariën, Peter; Santens, Patrick; Stevens, Michaël; Szmalec, Arnaud; Duyck, Wouter

2018-05-01

Until today, there is no satisfying explanation for why one language may recover worse than another in differential bilingual aphasia. One potential explanation that has been largely unexplored is that differential aphasia is the consequence of a loss of language control rather than a loss of linguistic representations. Language control is part of a general control mechanism that also manages non-linguistic cognitive control. If this system is impaired, patients with differential aphasia could still show bilingual language activation, but they may be unable to manage activation in non-target languages, so that performance in another language is hindered. To investigate whether a loss of cognitive control, rather than the loss of word representations in a particular language, might underlie differential aphasia symptoms. We compared the performance of seven bilinguals with differential and eight bilinguals with parallel aphasia with 19 control bilinguals in a lexical decision and a flanker task to assess bilingual language co-activation and non-linguistic control respectively. We found similar cognate effects in the three groups, indicating similar lexical processing across groups. Additionally, we found a larger non-linguistic control congruency effect only for the patients with differential aphasia. The present data indicate preserved language co-activation for patients with parallel as well as differential aphasia. Furthermore, the results suggest a general cognitive control dysfunction, specifically for differential aphasia. Taken together, the results of the current study provide further support for the hypothesis of impaired cognitive control abilities in patients with differential aphasia, which has both theoretical and practical implications. © 2018 Royal College of Speech and Language Therapists.

Risk assessment paradigm: an opportunity for rationalizing the choice of biological indicator during the validation of isolator biodecontamination cycles.

PubMed

Sansoë-Bourget, Emmanuelle

2006-01-01

The use of biological indicators is integral to the validation of isolator decontamination cycles. The difficulty in setting up the initial qualification of the decontamination cycle and especially the successive requalifications may vary as a function of not only the installation to be qualified and the sterilizing agent and generator used, but also as a function of the type of biological indicators used. In this article the manufacture and control of biological indicators are analyzed using the hazard analysis and critical control point (HACCP) approach. The HACCP risk analysis, which must take into account the application of the isolator being qualified or requalified, is an efficient simplification tool for performing a decontamination cycle using either hydrogen peroxide gas or peracetic acid in a reliable, economical, and reproducible way.

Working memory capacity and the scope and control of attention.

PubMed

Shipstead, Zach; Harrison, Tyler L; Engle, Randall W

2015-08-01

Complex span and visual arrays are two common measures of working memory capacity that are respectively treated as measures of attention control and storage capacity. A recent analysis of these tasks concluded that (1) complex span performance has a relatively stronger relationship to fluid intelligence and (2) this is due to the requirement that people engage control processes while performing this task. The present study examines the validity of these conclusions by examining two large data sets that include a more diverse set of visual arrays tasks and several measures of attention control. We conclude that complex span and visual arrays account for similar amounts of variance in fluid intelligence. The disparity relative to the earlier analysis is attributed to the present study involving a more complete measure of the latent ability underlying the performance of visual arrays. Moreover, we find that both types of working memory task have strong relationships to attention control. This indicates that the ability to engage attention in a controlled manner is a critical aspect of working memory capacity, regardless of the type of task that is used to measure this construct.

Apparatus for sensor failure detection and correction in a gas turbine engine control system

NASA Technical Reports Server (NTRS)

Spang, H. A., III; Wanger, R. P. (Inventor)

1981-01-01

A gas turbine engine control system maintains a selected level of engine performance despite the failure or abnormal operation of one or more engine parameter sensors. The control system employs a continuously updated engine model which simulates engine performance and generates signals representing real time estimates of the engine parameter sensor signals. The estimate signals are transmitted to a control computational unit which utilizes them in lieu of the actual engine parameter sensor signals to control the operation of the engine. The estimate signals are also compared with the corresponding actual engine parameter sensor signals and the resulting difference signals are utilized to update the engine model. If a particular difference signal exceeds specific tolerance limits, the difference signal is inhibited from updating the model and a sensor failure indication is provided to the engine operator.

Executive Functions in Children Who Experience Bullying Situations

PubMed Central

Medeiros, Wandersonia; Torro-Alves, Nelson; Malloy-Diniz, Leandro F.; Minervino, Carla M.

2016-01-01

Bullying is characterized by intentional, repetitive, and persistent aggressive behavior that causes damage to the victim. Many studies investigate the social and emotional aspects related to bullying, but few assess the cognitive aspects it involves. Studies with aggressive individuals indicate impairment in executive functioning and decision-making. The objective of this study was to assess hot and cold executive functions in children who experience bullying. A total of 60 children between 10 and 11 years of age were included in the study. They were divided into four groups: aggressors (bullies), victims, bully-victims, and control. Tests for decision-making, inhibitory control, working memory, and cognitive flexibility were used. The bully group made more unfavorable choices on the Iowa Gambling Task, which may indicate difficulties in the decision-making process. The victim group took longer to complete the Trail Making Test (Part B) than aggressors, suggesting lower cognitive flexibility in victims. The hypothesis that aggressors would have lower performance in other executive functions such as inhibitory control, working memory, and cognitive flexibility has not been confirmed. This study indicates that bullies have an impairment of hot executive functions whereas victims have a comparatively lower performance in cold executive functions. In addition to social and cultural variables, neurocognitive and emotional factors seem to influence the behavior of children in bullying situations. PMID:27616998

ACE DD genotype is unfavorable to Korean short-term muscle power athletes.

PubMed

Kim, C-H; Cho, J-Y; Jeon, J Y; Koh, Y G; Kim, Y-M; Kim, H-J; Park, M; Um, H-S; Kim, C

2010-01-01

The purpose of this study was to test the hypothesis that the ACE DD genotype is unfavorably associated with the ultimate power-oriented performance. To test the hypothesis we recruited a total of 848 subjects including 55 international level power-oriented athletes (High-performance), 100 national level power-oriented athletes (Mid-performance) and 693 healthy controls (Control) in Korea. Then the distributions of ACE polymorphism throughout these groups were analyzed. As a result, there was a gradual decrease of frequencies of the DD genotype with advancing levels of performance (Control vs. Mid-performance vs. High-performance=17.2% vs. 10.0% vs. 5.5%, p=0.002). Also, the frequencies of D allele decreased gradually with advancing levels of performance (Control vs. Mid-performance vs. High-performance=42.6% vs. 35.0% vs. 30.9%, p<0.01). Therefore, power-oriented athletes at the top level had a markedly diminished frequency of the DD genotype and the D allele. This finding gave 3.83 times lower probability of success in power-oriented sports for individuals with the DD genotype than those with the II+ ID genotype. In conclusion, these results indicate that Korean power-oriented athletes with a lower frequency of the DD genotype had a lower probability of success in power-oriented sports. Georg Thieme Verlag KG Stuttgart, New York.

Measuring, managing and maximizing refinery performance

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

Bascur, O.A.; Kennedy, J.P.

1996-01-01

Implementing continuous quality improvement is a confluence of total quality management, people empowerment, performance indicators and information engineering. Supporting information technologies allow a refiner to narrow the gap between management objectives and the process control level. Dynamic performance monitoring benefits come from production cost savings, improved communications and enhanced decision making. A refinery workgroup information flow model helps automate continuous improvement of processes, performance and the organization. The paper discusses the rethinking of refinery operations, dynamic performance monitoring, continuous process improvement, the knowledge coordinator and repository manager, an integrated plant operations workflow, and successful implementation.

Psychophysiological assessment and correction of spatial disorientation during simulated Orion spacecraft re-entry.

PubMed

Cowings, Patricia S; Toscano, William B; Reschke, Millard F; Tsehay, Addis

2018-03-02

The National Aeronautics and Space Administration (NASA) has identified a potential risk of spatial disorientation, motion sickness, and degraded performance to astronauts during re-entry and landing of the proposed Orion crew vehicle. The purpose of this study was to determine if a physiological training procedure, Autogenic-Feedback Training Exercise (AFTE), can mitigate these adverse effects. Fourteen men and six women were assigned to two groups (AFTE, no-treatment Control) matched for motion sickness susceptibility and gender. All subjects received a standard rotating chair test to determine motion sickness susceptibility; three training sessions on a manual performance task; and four exposures in the rotating chair (Orion tests) simulating angular accelerations of the crew vehicle during re-entry. AFTE subjects received 2 h of training before Orion tests 2, 3, and 4. Motion sickness symptoms, task performance, and physiological measures were recorded on all subjects. Results showed that the AFTE group had significantly lower symptom scores when compared to Controls on test 2 (p = .05), test 3 (p = .03), and test 4 (p = .02). Although there were no significant group differences on task performance, trends showed that AFTE subjects were less impaired than Controls. Heart rate change scores (20 rpm minus baseline) of AFTE subjects indicated significantly less reactivity on Test 4 compared to Test 1 (10.09 versus 16.59, p = .02), while Controls did not change significantly across tests. Results of this study indicate that AFTE may be an effective countermeasure for mitigating spatial disorientation and motion sickness in astronauts. Copyright © 2018. Published by Elsevier B.V.

Gross motor skill performance in children with and without visual impairments--research to practice.

PubMed

Wagner, Matthias O; Haibach, Pamela S; Lieberman, Lauren J

2013-10-01

The aim of this study was to provide an empirical basis for teaching gross motor skills in children with visual impairments. For this purpose, gross motor skill performance of 23, 6-12 year old, boys and girls who are blind (ICD-10 H54.0) and 28 sighted controls with comparable age and gender characteristics was compared on six locomotor and six object control tasks using the Test of Gross Motor Development-Second Edition. Results indicate that children who are blind perform significantly (p<.05) worse in all assessed locomotor and object control skills, whereby running, leaping, kicking and catching are the most affected skills, and corresponding differences are related to most running, leaping, kicking and catching component. Practical implications are provided. Copyright © 2013 Elsevier Ltd. All rights reserved.

Control of a Robotic Hand Using a Tongue Control System-A Prosthesis Application.

PubMed

Johansen, Daniel; Cipriani, Christian; Popovic, Dejan B; Struijk, Lotte N S A

2016-07-01

The aim of this study was to investigate the feasibility of using an inductive tongue control system (ITCS) for controlling robotic/prosthetic hands and arms. This study presents a novel dual modal control scheme for multigrasp robotic hands combining standard electromyogram (EMG) with the ITCS. The performance of the ITCS control scheme was evaluated in a comparative study. Ten healthy subjects used both the ITCS control scheme and a conventional EMG control scheme to complete grasping exercises with the IH1 Azzurra robotic hand implementing five grasps. Time to activate a desired function or grasp was used as the performance metric. Statistically significant differences were found when comparing the performance of the two control schemes. On average, the ITCS control scheme was 1.15 s faster than the EMG control scheme, corresponding to a 35.4% reduction in the activation time. The largest difference was for grasp 5 with a mean AT reduction of 45.3% (2.38 s). The findings indicate that using the ITCS control scheme could allow for faster activation of specific grasps or functions compared with a conventional EMG control scheme. For transhumeral and especially bilateral amputees, the ITCS control scheme could have a significant impact on the prosthesis control. In addition, the ITCS would provide bilateral amputees with the additional advantage of environmental and computer control for which the ITCS was originally developed.

The Effect of Modified Control Limits on the Performance of a Generic Commercial Aircraft Engine

NASA Technical Reports Server (NTRS)

Csank, Jeffrey T.; May, Ryan D.; Gou, Ten-Huei; Litt, Jonathan S.

2012-01-01

This paper studies the effect of modifying the control limits of an aircraft engine to obtain additional performance. In an emergency situation, the ability to operate an engine above its normal operating limits and thereby gain additional performance may aid in the recovery of a distressed aircraft. However, the modification of an engine s limits is complex due to the risk of an engine failure. This paper focuses on the tradeoff between enhanced performance and risk of either incurring a mechanical engine failure or compromising engine operability. The ultimate goal is to increase the engine performance, without a large increase in risk of an engine failure, in order to increase the probability of recovering the distressed aircraft. The control limit modifications proposed are to extend the rotor speeds, temperatures, and pressures to allow more thrust to be produced by the engine, or to increase the rotor accelerations and allow the engine to follow a fast transient. These modifications do result in increased performance; however this study indicates that these modifications also lead to an increased risk of engine failure.

The EyeHarp: A Gaze-Controlled Digital Musical Instrument

PubMed Central

Vamvakousis, Zacharias; Ramirez, Rafael

2016-01-01

We present and evaluate the EyeHarp, a new gaze-controlled Digital Musical Instrument, which aims to enable people with severe motor disabilities to learn, perform, and compose music using only their gaze as control mechanism. It consists of (1) a step-sequencer layer, which serves for constructing chords/arpeggios, and (2) a melody layer, for playing melodies and changing the chords/arpeggios. We have conducted a pilot evaluation of the EyeHarp involving 39 participants with no disabilities from both a performer and an audience perspective. In the first case, eight people with normal vision and no motor disability participated in a music-playing session in which both quantitative and qualitative data were collected. In the second case 31 people qualitatively evaluated the EyeHarp in a concert setting consisting of two parts: a solo performance part, and an ensemble (EyeHarp, two guitars, and flute) performance part. The obtained results indicate that, similarly to traditional music instruments, the proposed digital musical instrument has a steep learning curve, and allows to produce expressive performances both from the performer and audience perspective. PMID:27445885

The development and functional control of reading-comprehension behavior.

PubMed

Rosenbaum, M S; Breiling, J

1976-01-01

Reading comprehension, indicated by motor behavior and multiple-choice picture selection called for in written instructions, was taught to an autistic child using verbal prompts, modelling, and physical guidance. The child was rewarded for correct behaviors to training items; nonrewarded probes were used to assess generalization. Probable maintaining events were assessed through their sequential removal in a reversal design. Results showed: (a) following acquisition, performance was maintained at a near-100% level when candy, praise, attention, and training were removed, (b) absence of other persons was correlated with a marked decrease in performance, whereas their presence was associated with performance at near 100%, and (c) performance generalized to probes and across experimenters. Rewards, which may have been reinforcing during acquisition, did not appear necessary to maintain later performance. Instead, presence of others (a setting event) was demonstrated to have control over maintained performance.

Control processes through the suppression of the automatic response activation triggered by task-irrelevant information in the Simon-type tasks.

PubMed

Kim, Sanga; Lee, Sang Ho; Cho, Yang Seok

2015-11-01

The congruency sequence effect, one of the indices of cognitive control, refers to a smaller congruency effect after an incongruent than congruent trial. Although the effect has been found across a variety of conflict tasks, there is not yet agreement on the underlying mechanism. The present study investigated the mechanism underlying cognitive control by using a cross-task paradigm. In Experiments 1, 2, and 3, participants performed a modified Simon task and a spatial Stroop task alternately in a trial-by-trial manner. The task-irrelevant dimension of the two tasks was perceptually and conceptually identical in Experiment 1, whereas it was perceptually different but conceptually identical in Experiment 2. The response sets for both tasks were different in Experiment 3. In Experiment 4, participants performed two Simon tasks with different task-relevant dimensions. In all experiments in which the task-irrelevant dimension and response mode were shared, significant congruency sequence effects were found between the two different congruencies, indicating that Simon-type conflicts were resolved by a control mechanism, which is specific to an abstract task-irrelevant stimulus spatial dimension. Copyright © 2015 Elsevier B.V. All rights reserved.

International Space Station Acoustics - A Status Report

NASA Technical Reports Server (NTRS)

Allen, Christopher S.; Denham, Samuel A.

2011-01-01

It is important to control acoustic noise aboard the International Space Station (ISS) to provide a satisfactory environment for voice communications, crew productivity, and restful sleep, and to minimize the risk for temporary and permanent hearing loss. Acoustic monitoring is an important part of the noise control process on ISS, providing critical data for trend analysis, noise exposure analysis, validation of acoustic analysis and predictions, and to provide strong evidence for ensuring crew health and safety, thus allowing Flight Certification. To this purpose, sound level meter (SLM) measurements and acoustic noise dosimetry are routinely performed. And since the primary noise sources on ISS include the environmental control and life support system (fans and airflow) and active thermal control system (pumps and water flow), acoustic monitoring will indicate changes in hardware noise emissions that may indicate system degradation or performance issues. This paper provides the current acoustic levels in the ISS modules and sleep stations, and is an update to the status presented in 20031. Many new modules, and sleep stations have been added to the ISS since that time. In addition, noise mitigation efforts have reduced noise levels in some areas. As a result, the acoustic levels on the ISS have improved.

Cognitive control in context: working memory capacity and proactive control.

PubMed

Redick, Thomas S

2014-01-01

Working memory is important for maintaining critical information in an active state to guide future behavior. The executive-attention theory of working memory capacity (WMC; Engle & Kane, 2004) argues that goal maintenance is important for response selection when stimuli are associated with competing responses. Braver, Burgess, and Gray (2007) have labeled this type of preparatory activity proactive control. Previous WMC studies have not allowed individuals to use goal information to prepare a specific response in advance of the stimulus. The current experiment used different versions of a cue-probe task to examine the relationship between individual differences in WMC and proactive control. Across three versions of the AX version of the Continuous Performance Test, the proportion of targets was manipulated to affect both the predictive validity of the A cue and the prepotency of the target response to X probes. The results indicated that the high-WMC individuals used the cue information to prepare responses in advance only when a specific probe was likely to occur. In contrast, the performance of the low-WMC individuals was less dependent upon the cue and more contingent upon overall response frequencies. The results indicate that individual differences in WMC are related to proactive control and anticipation, and important for translating cognition into action. © 2013 Elsevier B.V. All rights reserved.

Interactive effects of trait and state affect on top-down control of attention.

PubMed

Hur, Juyoen; Miller, Gregory A; McDavitt, Jenika R B; Spielberg, Jeffrey M; Crocker, Laura D; Infantolino, Zachary P; Towers, David N; Warren, Stacie L; Heller, Wendy

2015-08-01

Few studies have investigated how attentional control is affected by transient affective states while taking individual differences in affective traits into consideration. In this study, participants completed a color-word Stroop task immediately after undergoing a positive, neutral or negative affective context manipulation (ACM). Behavioral performance was unaffected by any ACM considered in isolation. For individuals high in trait negative affect (NA), performance was impaired by the negative but not the positive or neutral ACM. Neuroimaging results indicate that activity in primarily top-down control regions of the brain (inferior frontal gyrus and dorsal anterior cingulate cortex) was suppressed in the presence of emotional arousal (both negative and positive ACMs). This effect appears to have been exacerbated or offset by co-occurring activity in other top-down control regions (parietal) and emotion processing regions (orbitofrontal cortex, amygdala and nucleus accumbens) as a function of the valence of state affect (positive or negative) and trait affect (trait NA or trait PA). Neuroimaging results are consistent with behavioral findings. In combination, they indicate both additive and interactive influences of trait and state affect on top-down control of attention. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Identification of optimal feedback control rules from micro-quadrotor and insect flight trajectories.

PubMed

Faruque, Imraan A; Muijres, Florian T; Macfarlane, Kenneth M; Kehlenbeck, Andrew; Humbert, J Sean

2018-06-01

This paper presents "optimal identification," a framework for using experimental data to identify the optimality conditions associated with the feedback control law implemented in the measurements. The technique compares closed loop trajectory measurements against a reduced order model of the open loop dynamics, and uses linear matrix inequalities to solve an inverse optimal control problem as a convex optimization that estimates the controller optimality conditions. In this study, the optimal identification technique is applied to two examples, that of a millimeter-scale micro-quadrotor with an engineered controller on board, and the example of a population of freely flying Drosophila hydei maneuvering about forward flight. The micro-quadrotor results show that the performance indices used to design an optimal flight control law for a micro-quadrotor may be recovered from the closed loop simulated flight trajectories, and the Drosophila results indicate that the combined effect of the insect longitudinal flight control sensing and feedback acts principally to regulate pitch rate.

Preliminary Retrospective Analysis of Daily Tomotherapy Output Constancy Checks Using Statistical Process Control.

PubMed

Mezzenga, Emilio; D'Errico, Vincenzo; Sarnelli, Anna; Strigari, Lidia; Menghi, Enrico; Marcocci, Francesco; Bianchini, David; Benassi, Marcello

2016-01-01

The purpose of this study was to retrospectively evaluate the results from a Helical TomoTherapy Hi-Art treatment system relating to quality controls based on daily static and dynamic output checks using statistical process control methods. Individual value X-charts, exponentially weighted moving average charts, and process capability and acceptability indices were used to monitor the treatment system performance. Daily output values measured from January 2014 to January 2015 were considered. The results obtained showed that, although the process was in control, there was an out-of-control situation in the principal maintenance intervention for the treatment system. In particular, process capability indices showed a decreasing percentage of points in control which was, however, acceptable according to AAPM TG148 guidelines. Our findings underline the importance of restricting the acceptable range of daily output checks and suggest a future line of investigation for a detailed process control of daily output checks for the Helical TomoTherapy Hi-Art treatment system.

Vestibular and Somatosensory Covergence in Postural Equilibrium Control: Insights from Spaceflight and Bed Rest Studies

NASA Technical Reports Server (NTRS)

Mulavara, A. P.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Peters, B. T.; Phillips, T.; Platts, S. H.;

Propulsion system/flight control integration for supersonic aircraft

NASA Technical Reports Server (NTRS)

Reukauf, P. J.; Burcham, F. W., Jr.

1976-01-01

Digital integrated control systems are studied. Such systems allow minimization of undesirable interactions while maximizing performance at all flight conditions. One such program is the YF-12 cooperative control program. The existing analog air data computer, autothrottle, autopilot, and inlet control systems are converted to digital systems by using a general purpose airborne computer and interface unit. Existing control laws are programed and tested in flight. Integrated control laws, derived using accurate mathematical models of the airplane and propulsion system in conjunction with modern control techniques, are tested in flight. Analysis indicates that an integrated autothrottle autopilot gives good flight path control and that observers are used to replace failed sensors.

Evaluation of pharmacy generalists performing antimicrobial stewardship services.

PubMed

Carreno, Joseph J; Kenney, Rachel M; Bloome, Mary; McDonnell, Jane; Rodriguez, Jennifer; Weinmann, Allison; Kilgore, Paul E; Davis, Susan L

2015-08-01

Improvements in medication use achieved by pharmacy generalists using a care bundle approach to antimicrobial stewardship are reported. A six-month prospective, repeated-treatment, quasi-experimental study involving three month-long intervention periods and three month-long control periods was conducted in the setting of an existing antimicrobial stewardship program at a large hospital. The intervention involved prospective audit and feedback conducted by pharmacy generalists who were trained in an antimicrobial stewardship care bundle approach. During control months, a pharmacy generalist who was not trained in antimicrobial stewardship rounded with the multidisciplinary team and provided standard-of-care pharmacy services. The primary endpoint was compliance with a care bundle of four antimicrobial stewardship metrics: documentation of indication for therapy in the medical record, selection of empirical therapy according to institutional guidelines, documented performance of indicated culture testing, and deescalation of therapy when indicated. Two-hundred eighty-six patients were enrolled in the study: 124 in the intervention group and 162 in the control group. The cumulative rate of full compliance with all care bundle components during the six-month study was significantly greater during intervention months than during control months (68.5% versus 45.7%, p < 0.001). After adjusting for infection type, antimicrobial stewardship provided by an intervention-group pharmacist was associated with improved care bundle compliance (adjusted odds ratio, 2.70; p < 0.001). No significant differences in patient outcomes during intervention and control months were detected. Pharmacy generalists trained to comply with a systematic care bundle approach enhanced the quality of antimicrobial management. Copyright © 2015 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Predictors of Global Self-Worth and Academic Performance among Regular Education, Learning Disabled, and Continuation High School Students.

ERIC Educational Resources Information Center

Wiest, Dudley J.; Wong, Eugene H.; Kreil, Dennis A.

1998-01-01

The ability of measures of perceived competence, control, and autonomy support to predict self-worth and academic performance was studied across groups of high school students. Stepwise regression analyses indicate these variables in model predict self-worth and grade point average. In addition, levels of school status and depression predict…

Understanding the Impact of Training on Performance

DTIC Science & Technology

2014-05-01

learning argue that this method encourages metacognitive activity and self -regulation of learning; which, in turn, can aid the development of adaptable...Frese, M. (2005). Self -regulation in error management training: Emotion control and metacognition as mediators of performance effects. Journal...on aptitude by treatment interactions that indicate the effectiveness of training interventions can differ depending on trainee aptitude for self

Orbiter fuel cell performance constraints. STS/OPS Pratt Whitney fuel cells. Operating limits for mission planning

NASA Technical Reports Server (NTRS)

Kolkhorst, H. E.

1980-01-01

The orbiter fuel cell powerplant (FCP) performance constraints listed in the Shuttle Operational Data Book (SODB) were analyzed using the shuttle environmental control requirements evaluation tool. The effects of FCP lifetime, coolant loops, and FCP voltage output were considered. Results indicate that the FCP limits defined in the SODB are not valid.

Long-term pavement performance indicators for failed materials.

DOT National Transportation Integrated Search

2016-04-01

State Transportation Agencies (STAs) use quality control/quality assurance (QC/QA) specifications to guide the testing and inspection of : road pavement construction. Although failed materials of pavement rarely occur in practice, it is critical to h...

Double-blind, placebo-controlled food challenge in adults in everyday clinical practice: a reappraisal of their limitations and real indications.

PubMed

Asero, Riccardo; Fernandez-Rivas, Montserrat; Knulst, André C; Bruijnzeel-Koomen, Carla Afm

2009-08-01

The double-blind, placebo-controlled food challenge (DBPCFC) is widely considered as the 'gold standard' for the diagnosis of food allergy. However, in adult patients, this procedure is rather rarely performed outside the academic context. This review article aims to reappraise the pros and cons of DBPCFC and to elicit some critical thoughts and discussions about the real indications of this diagnostic procedure in adult patients in everyday practice. There are many data showing that the DBPCFC poses a number of critical problems that are difficult to overcome in normal outpatient clinics and hospitals, and that are generally not addressed in most articles dealing with this issue. Performing DBPCFC poses a number of practical problems and has several pitfalls, which make its routine use in normal clinical settings generally impossible. This review article shows that the need for this procedure in adult patients seems in effect very little and specifies new, more limited indications to its use in everyday practice. Further, it suggests a role for the open challenge, which lacks several of the disadvantages of DBPCFC.

Using eye movements as an index of implicit face recognition in autism spectrum disorder.

PubMed

Hedley, Darren; Young, Robyn; Brewer, Neil

2012-10-01

Individuals with an autism spectrum disorder (ASD) typically show impairment on face recognition tasks. Performance has usually been assessed using overt, explicit recognition tasks. Here, a complementary method involving eye tracking was used to examine implicit face recognition in participants with ASD and in an intelligence quotient-matched non-ASD control group. Differences in eye movement indices between target and foil faces were used as an indicator of implicit face recognition. Explicit face recognition was assessed using old-new discrimination and reaction time measures. Stimuli were faces of studied (target) or unfamiliar (foil) persons. Target images at test were either identical to the images presented at study or altered by changing the lighting, pose, or by masking with visual noise. Participants with ASD performed worse than controls on the explicit recognition task. Eye movement-based measures, however, indicated that implicit recognition may not be affected to the same degree as explicit recognition. Autism Res 2012, 5: 363-379. © 2012 International Society for Autism Research, Wiley Periodicals, Inc. © 2012 International Society for Autism Research, Wiley Periodicals, Inc.

Effect of Stepwise Pressure Change on Porosity Evolution during Directional Solidification in Small Cylindrical Channels

NASA Technical Reports Server (NTRS)

Grugel, R.N.; Lee, C.P.; Cox, M.C.; Blandford, B.T.; Anilkumar, A.V.

2008-01-01

Controlled directional solidification experiments were performed in capillary channels, using nitrogen-saturated succinonitrile, to examine the effect of an in-situ stepwise processing pressure increase on an isolated pore evolution. Two experiments were performed using different processing pressure input profiles. The results indicate that a processing pressure increase has a transient effect on pore growth geometry characterized by an initial phase of decreasing pore diameter, followed by a recovery phase of increasing pore diameter. The experimental results also show that processing pressure can be used as a control parameter to either increase or terminate porosity formation. A theoretical model is introduced which indicates that the pore formation process is limited by the diffusion of solute-gas through the melt, and that the observed response toa pressure increase is attributed to the re-equilibration of solute concentration in the melt associated with the increased melt pressure.

Methodology for Evaluating Security Controls Based on Key Performance Indicators and Stakeholder Mission

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

Sheldon, Frederick T; Abercrombie, Robert K; Mili, Ali

2009-01-01

Information security continues to evolve in response to disruptive changes with a persistent focus on information-centric controls and a healthy debate about balancing endpoint and network protection, with a goal of improved enterprise/business risk management. Economic uncertainty, intensively collaborative styles of work, virtualization, increased outsourcing and ongoing compliance pressures require careful consideration and adaptation. This paper proposes a Cyberspace Security Econometrics System (CSES) that provides a measure (i.e., a quantitative indication) of reliability, performance and/or safety of a system that accounts for the criticality of each requirement as a function of one or more stakeholders interests in that requirement. Formore » a given stakeholder, CSES reflects the variance that may exist among the stakes she/he attaches to meeting each requirement. This paper introduces the basis, objectives and capabilities for the CSES including inputs/outputs as well as the structural and mathematical underpinnings.« less

Attitude control study for a large flexible spacecraft using a Solar Electric Propulsion System (SEPS)

NASA Technical Reports Server (NTRS)

Tolivar, A. F.; Key, R. W.

1980-01-01

The attitude control performance of the solar electric propulsion system (SEPS) was evaluated. A thrust vector control system for powered flight control was examined along with a gas jet reaction control system, and a reaction wheel system, both of which have been proposed for nonpowered flight control. Comprehensive computer simulations of each control system were made and evaluated using a 30 mode spacecraft model. Results obtained indicate that thrust vector control and reaction wheel systems offer acceptable smooth proportional control. The gas jet control system is shown to be risky for a flexible structure such as SEPS, and is therefore, not recommended as a primary control method.

Effects of Exercise Intervention on Event-Related Potential and Task Performance Indices of Attention Networks in Children with Developmental Coordination Disorder

ERIC Educational Resources Information Center

Tsai, Chia-Liang; Wang, Chun-Hao; Tseng, Yu-Ting

2012-01-01

The study investigated whether 10-week soccer training can benefit the inhibitory control and neuroelectric indices in children with developmental coordination disorder (DCD). Fifty-one children were divided into groups of typically developing (TD, n = 21), DCD-training (n = 16), and DCD non-training (n=14) individuals using the for Children test,…

Perceived Academic Performance, Self-Esteem and Locus of Control as Indicators of Need for Assessment of Adolescent Suicide Risk: Implications for Teachers

ERIC Educational Resources Information Center

Martin, Graham; Richardson, Angela S.; Bergen, Helen A.; Roeger, Leigh; Allison, Stephen

2005-01-01

Introduction: There is currently a need for research into indicators that could be used by non-clinical professionals working with young people, to inform the need for referral for further clinical assessment of those at risk of suicide. Method: Participants of this repeated measures longitudinal study, were 2603, 2485, and 2246 school students…

Detaching reasons from aims: fair play and well-being in soccer as a function of pursuing performance-approach goals for autonomous or controlling reasons.

PubMed

Vansteenkiste, Maarten; Mouratidis, Athanasios; Lens, Willy

2010-04-01

In two cross-sectional studies we investigated whether soccer players' well-being (Study 1) and moral functioning (Studies 1 and 2) is related to performance-approach goals and to the autonomous and controlling reasons underlying their pursuit. In support of our hypotheses, we found in Study 1 that autonomous reasons were positively associated with vitality and positive affect, whereas controlling reasons were positively related to negative affect and mostly unrelated to indicators of morality. To investigate the lack of systematic association with moral outcomes, we explored in Study 2 whether performance-approach goals or their underlying reasons would yield an indirect relation to moral outcomes through their association with players' objectifying attitude-their tendency to depersonalize their opponents. Structural equation modeling showed that controlling reasons for performance-approach goals were positively associated with an objectifying attitude, which in turn was positively associated to unfair functioning. Results are discussed within the achievement goal perspective (Elliot, 2005) and self-determination theory (Deci & Ryan, 2000).

Use of Emotional Cues for Lexical Learning: A Comparison of Autism Spectrum Disorder and Fragile X Syndrome

PubMed Central

Thurman, Angela John; McDuffie, Andrea; Kover, Sara T.; Hagerman, Randi; Channell, Marie Moore; Mastergeorge, Ann; Abbeduto, Leonard

2014-01-01

The present study evaluated the ability of males with fragile X syndrome (FXS), nonsyndromic autism spectrum disorder (ASD), or typical development to learn new words by using as a cue to the intended referent an emotional reaction indicating a successful (excitement) or unsuccessful (disappointment) search for a novel object. Performance for all groups exceeded chance-levels in both search conditions. In the Successful Search condition, participants with nonsyndromic ASD performed similarly to participants with FXS after controlling for severity of ASD. In the Unsuccessful Search condition, participants with FXS performed significantly worse than participants with nonsyndromic ASD, after controlling for severity of ASD. Predictors of performance in both search conditions differed between the three groups. Theoretical and clinical implications are discussed. PMID:25318904

Robust Nonlinear Feedback Control of Aircraft Propulsion Systems

NASA Technical Reports Server (NTRS)

Garrard, William L.; Balas, Gary J.; Litt, Jonathan (Technical Monitor)

2001-01-01

This is the final report on the research performed under NASA Glen grant NASA/NAG-3-1975 concerning feedback control of the Pratt & Whitney (PW) STF 952, a twin spool, mixed flow, after burning turbofan engine. The research focussed on the design of linear and gain-scheduled, multivariable inner-loop controllers for the PW turbofan engine using H-infinity and linear, parameter-varying (LPV) control techniques. The nonlinear turbofan engine simulation was provided by PW within the NASA Rocket Engine Transient Simulator (ROCETS) simulation software environment. ROCETS was used to generate linearized models of the turbofan engine for control design and analysis as well as the simulation environment to evaluate the performance and robustness of the controllers. Comparison between the H-infinity, and LPV controllers are made with the baseline multivariable controller and developed by Pratt & Whitney engineers included in the ROCETS simulation. Simulation results indicate that H-infinity and LPV techniques effectively achieve desired response characteristics with minimal cross coupling between commanded values and are very robust to unmodeled dynamics and sensor noise.

The effects of age, glucose ingestion and gluco-regulatory control on episodic memory.

PubMed

Riby, Leigh Martin; Meikle, Andrew; Glover, Cheryl

2004-09-01

Previous research has been inconclusive regarding the impact of glucose ingestion and gluco-regulatory control on cognitive performance in healthy older adults. The aim of this research was to determine whether glucose specifically enhanced episodic memory in an older population. In addition, the link between individual differences in glucose regulation and the magnitude of the enhancement effect was examined. A within subjects, counterbalanced, crossover design was used with 20 participants (60-80 year olds), each serving as his/her control. Episodic memory was tested by presenting unrelated paired associates followed by immediate and delayed cued recall, and delayed recognition, under single and dual task conditions. In addition, a battery of cognitive tests was administered, including tests of semantic memory, working memory and speed of processing. Glucose ingestion was found to largely facilitate performance of episodic memory. Furthermore, subsidiary analyses found that gluco-regulatory efficiency predicted episodic memory performance in both control and glucose conditions. A boost in performance after glucose ingestion was particularly seen in the episodic memory domain. Notably, strong evidence was provided for the utility of gluco-regulatory control measures as indicators of cognitive decline in the elderly.

Mathematical Modeling of RNA-Based Architectures for Closed Loop Control of Gene Expression.

PubMed

Agrawal, Deepak K; Tang, Xun; Westbrook, Alexandra; Marshall, Ryan; Maxwell, Colin S; Lucks, Julius; Noireaux, Vincent; Beisel, Chase L; Dunlop, Mary J; Franco, Elisa

2018-05-08

Feedback allows biological systems to control gene expression precisely and reliably, even in the presence of uncertainty, by sensing and processing environmental changes. Taking inspiration from natural architectures, synthetic biologists have engineered feedback loops to tune the dynamics and improve the robustness and predictability of gene expression. However, experimental implementations of biomolecular control systems are still far from satisfying performance specifications typically achieved by electrical or mechanical control systems. To address this gap, we present mathematical models of biomolecular controllers that enable reference tracking, disturbance rejection, and tuning of the temporal response of gene expression. These controllers employ RNA transcriptional regulators to achieve closed loop control where feedback is introduced via molecular sequestration. Sensitivity analysis of the models allows us to identify which parameters influence the transient and steady state response of a target gene expression process, as well as which biologically plausible parameter values enable perfect reference tracking. We quantify performance using typical control theory metrics to characterize response properties and provide clear selection guidelines for practical applications. Our results indicate that RNA regulators are well-suited for building robust and precise feedback controllers for gene expression. Additionally, our approach illustrates several quantitative methods useful for assessing the performance of biomolecular feedback control systems.

V1 projection zone signals in human macular degeneration depend on task, not stimulus.

PubMed

Masuda, Yoichiro; Dumoulin, Serge O; Nakadomari, Satoshi; Wandell, Brian A

2008-11-01

We used functional magnetic resonance imaging to assess abnormal cortical signals in humans with juvenile macular degeneration (JMD). These signals have been interpreted as indicating large-scale cortical reorganization. Subjects viewed a stimulus passively or performed a task; the task was either related or unrelated to the stimulus. During passive viewing, or while performing tasks unrelated to the stimulus, there were large unresponsive V1 regions. These regions included the foveal projection zone, and we refer to them as the lesion projection zone (LPZ). In 3 JMD subjects, we observed highly significant responses in the LPZ while they performed stimulus-related judgments. In control subjects, where we presented the stimulus only within the peripheral visual field, there was no V1 response in the foveal projection zone in any condition. The difference between JMD and control responses can be explained by hypotheses that have very different implications for V1 reorganization. In controls retinal afferents carry signals indicating the presence of a uniform (zero-contrast) region of the visual field. Deletion of retinal input may 1) spur the formation of new cortical pathways that carry task-dependent signals (reorganization), or 2) unmask preexisting task-dependent cortical signals that ordinarily are suppressed by the deleted signals (no reorganization).

V1 Projection Zone Signals in Human Macular Degeneration Depend on Task, not Stimulus

PubMed Central

Dumoulin, Serge O.; Nakadomari, Satoshi; Wandell, Brian A.

2008-01-01

We used functional magnetic resonance imaging to assess abnormal cortical signals in humans with juvenile macular degeneration (JMD). These signals have been interpreted as indicating large-scale cortical reorganization. Subjects viewed a stimulus passively or performed a task; the task was either related or unrelated to the stimulus. During passive viewing, or while performing tasks unrelated to the stimulus, there were large unresponsive V1 regions. These regions included the foveal projection zone, and we refer to them as the lesion projection zone (LPZ). In 3 JMD subjects, we observed highly significant responses in the LPZ while they performed stimulus-related judgments. In control subjects, where we presented the stimulus only within the peripheral visual field, there was no V1 response in the foveal projection zone in any condition. The difference between JMD and control responses can be explained by hypotheses that have very different implications for V1 reorganization. In controls retinal afferents carry signals indicating the presence of a uniform (zero-contrast) region of the visual field. Deletion of retinal input may 1) spur the formation of new cortical pathways that carry task-dependent signals (reorganization), or 2) unmask preexisting task-dependent cortical signals that ordinarily are suppressed by the deleted signals (no reorganization). PMID:18250083

Measures of static postural control moderate the association of strength and power with functional dynamic balance.

PubMed

Forte, Roberta; Boreham, Colin A G; De Vito, Giuseppe; Ditroilo, Massimiliano; Pesce, Caterina

2014-12-01

Age-related reductions in strength and power are considered to negatively impact balance control, but the existence of a direct association is still an issue of debate. This is possibly due to the fact that balance assessment is complex, reflects different underlying physiologic mechanisms and involves quantitative measurements of postural sway or timing of performance during balance tasks. The present study evaluated the moderator effect of static postural control on the association of power and strength with dynamic balance tasks. Fifty-seven healthy 65-75 year old individuals performed tests of dynamic functional balance (walking speed under different conditions) and of strength, power and static postural control. Dynamic balance performance (walking speed) was associated with lower limb strength and power, as well as postural control under conditions requiring postural adjustments (narrow surface walking r(2) = 0.31, p < 0.001). An interaction effect between strength and static postural control was found with narrow surface walking and talking while walking (change of β 0.980, p < 0.001 in strength for 1 SD improvements in static postural control for narrow walking, and [Formula: see text] -0.730, p < 0.01 in talking while walking). These results indicate that good static postural control facilitates the utilisation of lower limb strength to better perform complex, dynamic functional balance tasks. Practical implications for assessment and training are discussed.

The modality effect of ego depletion: Auditory task modality reduces ego depletion.

PubMed

Li, Qiong; Wang, Zhenhong

2016-08-01

An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Bristled shark skin: a microgeometry for boundary layer control?

PubMed

Lang, A W; Motta, P; Hidalgo, P; Westcott, M

2008-12-01

There exists evidence that some fast-swimming shark species may have the ability to bristle their scales during fast swimming. Experimental work using a water tunnel facility has been performed to investigate the flow field over and within a bristled shark skin model submerged within a boundary layer to deduce the possible boundary layer control mechanisms being used by these fast-swimming sharks. Fluorescent dye flow visualization provides evidence of the formation of embedded cavity vortices within the scales. Digital particle image velocimetry (DPIV) data, used to evaluate the cavity vortex formation and boundary layer characteristics close to the surface, indicate increased momentum in the slip layer forming above the scales. This increase in flow velocity close to the shark's skin is indicative of boundary layer control mechanisms leading to separation control and possibly transition delay for the bristled shark skin microgeometry.

Improving the Robustness of Real-Time Myoelectric Pattern Recognition against Arm Position Changes in Transradial Amputees

PubMed Central

Geng, Yanjuan; Wei, Yue

2017-01-01

Previous studies have showed that arm position variations would significantly degrade the classification performance of myoelectric pattern-recognition-based prosthetic control, and the cascade classifier (CC) and multiposition classifier (MPC) have been proposed to minimize such degradation in offline scenarios. However, it remains unknown whether these proposed approaches could also perform well in the clinical use of a multifunctional prosthesis control. In this study, the online effect of arm position variation on motion identification was evaluated by using a motion-test environment (MTE) developed to mimic the real-time control of myoelectric prostheses. The performance of different classifier configurations in reducing the impact of arm position variation was investigated using four real-time metrics based on dataset obtained from transradial amputees. The results of this study showed that, compared to the commonly used motion classification method, the CC and MPC configurations improved the real-time performance across seven classes of movements in five different arm positions (8.7% and 12.7% increments of motion completion rate, resp.). The results also indicated that high offline classification accuracy might not ensure good real-time performance under variable arm positions, which necessitated the investigation of the real-time control performance to gain proper insight on the clinical implementation of EMG-pattern-recognition-based controllers for limb amputees. PMID:28523276

International note: Prediction of mathematics work ethic and performance from behavioral, normative, and control beliefs among Qatari adolescents.

PubMed

Areepattamannil, Shaljan; Abdelfattah, Faisal; Mahasneh, Randa Ali; Khine, Myint Swe; Welch, Anita G; Melkonian, Michael; Al Nuaimi, Samira Ahmed

2016-01-01

Over half-a-million adolescents take part in each cycle of the Program for International Student Assessment (PISA). Yet often, researchers and policy makers across the globe tend to focus their attention primarily on the academic trajectories of adolescents hailing from highly successful education systems. Hence, a vast majority of the adolescent population who regionally and globally constitute the 'long tail of underachievement' often remain unnoticed and underrepresented in the growing literature on adolescents' academic trajectories. The present study, therefore, explored the relations of dispositions toward mathematics, subjective norms in mathematics, and perceived control of success in mathematics to mathematics work ethic as well as mathematics performance; and the mediational role of mathematics work ethic in the association between dispositional, normative, and control beliefs and mathematics performance among adolescents in one of the lowest performing education systems, Qatar. Structural equation modeling (SEM) analyses revealed that Qatari adolescents' dispositional, normative, and control beliefs about mathematics were significantly associated with their mathematics work ethic and mathematics performance, and mathematics work ethic significantly mediated the relationship between dispositional, normative, and control beliefs about mathematics and mathematics performance. However, multi-group SEM analyses indicated that these relationships were not invariant across the gender and the SES groups. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

A New Performance Improvement Model: Adding Benchmarking to the Analysis of Performance Indicator Data.

PubMed

Al-Kuwaiti, Ahmed; Homa, Karen; Maruthamuthu, Thennarasu

2016-01-01

A performance improvement model was developed that focuses on the analysis and interpretation of performance indicator (PI) data using statistical process control and benchmarking. PIs are suitable for comparison with benchmarks only if the data fall within the statistically accepted limit-that is, show only random variation. Specifically, if there is no significant special-cause variation over a period of time, then the data are ready to be benchmarked. The proposed Define, Measure, Control, Internal Threshold, and Benchmark model is adapted from the Define, Measure, Analyze, Improve, Control (DMAIC) model. The model consists of the following five steps: Step 1. Define the process; Step 2. Monitor and measure the variation over the period of time; Step 3. Check the variation of the process; if stable (no significant variation), go to Step 4; otherwise, control variation with the help of an action plan; Step 4. Develop an internal threshold and compare the process with it; Step 5.1. Compare the process with an internal benchmark; and Step 5.2. Compare the process with an external benchmark. The steps are illustrated through the use of health care-associated infection (HAI) data collected for 2013 and 2014 from the Infection Control Unit, King Fahd Hospital, University of Dammam, Saudi Arabia. Monitoring variation is an important strategy in understanding and learning about a process. In the example, HAI was monitored for variation in 2013, and the need to have a more predictable process prompted the need to control variation by an action plan. The action plan was successful, as noted by the shift in the 2014 data, compared to the historical average, and, in addition, the variation was reduced. The model is subject to limitations: For example, it cannot be used without benchmarks, which need to be calculated the same way with similar patient populations, and it focuses only on the "Analyze" part of the DMAIC model.

Women with fibromyalgia's experience with three motion-controlled video game consoles and indicators of symptom severity and performance of activities of daily living.

PubMed

Mortensen, Jesper; Kristensen, Lola Qvist; Brooks, Eva Petersson; Brooks, Anthony Lewis

2015-01-01

Little is known of Motion-Controlled Video Games (MCVGs) as an intervention for people with chronic pain. The aim of this study was to explore the experience women with fibromyalgia syndrome (FMS) had, using commercially available MCVGs; and to investigate indicators of symptom severity and performance of activities of daily living (ADL). Of 15 female participants diagnosed with FMS, 7 completed a program of five sessions with Nintendo Wii (Wii), five sessions with PlayStation 3 Move (PS3 Move) and five sessions with Microsoft Xbox Kinect (Xbox Kinect). Interviews were conducted at baseline and post-intervention and were supported by data from observation and self-reported assessment. Participants experienced play with MCVGs as a way to get distraction from pain symptoms while doing fun and manageable exercise. They enjoyed the slow pace and familiarity of Wii, while some considered PS3 Move to be too fast paced. Xbox Kinect was reported as the best console for exercise. There were no indication of general improvement in symptom severity or performance of ADL. This study demonstrated MCVG as an effective healthcare intervention for the women with FMS who completed the program, with regards to temporary pain relief and enjoyable low impact exercise. Implications for Rehabilitation Exercise is recommended in the management of fibromyalgia syndrome (FMS). People with FMS often find it counterintuitive to exercise because of pain exacerbation, which may influence adherence to an exercise program. Motion-controlled video games may offer temporary pain relief and fun low impact exercise for women with FMS.

Performance of children with developmental dyslexia on high and low topological entropy artificial grammar learning task.

PubMed

Katan, Pesia; Kahta, Shani; Sasson, Ayelet; Schiff, Rachel

2017-07-01

Graph complexity as measured by topological entropy has been previously shown to affect performance on artificial grammar learning tasks among typically developing children. The aim of this study was to examine the effect of graph complexity on implicit sequential learning among children with developmental dyslexia. Our goal was to determine whether children's performance depends on the complexity level of the grammar system learned. We conducted two artificial grammar learning experiments that compared performance of children with developmental dyslexia with that of age- and reading level-matched controls. Experiment 1 was a high topological entropy artificial grammar learning task that aimed to establish implicit learning phenomena in children with developmental dyslexia using previously published experimental conditions. Experiment 2 is a lower topological entropy variant of that task. Results indicated that given a high topological entropy grammar system, children with developmental dyslexia who were similar to the reading age-matched control group had substantial difficulty in performing the task as compared to typically developing children, who exhibited intact implicit learning of the grammar. On the other hand, when tested on a lower topological entropy grammar system, all groups performed above chance level, indicating that children with developmental dyslexia were able to identify rules from a given grammar system. The results reinforced the significance of graph complexity when experimenting with artificial grammar learning tasks, particularly with dyslexic participants.

Cursor control by Kalman filter with a non-invasive body–machine interface

PubMed Central

Seáñez-González, Ismael; Mussa-Ivaldi, Ferdinando A

2015-01-01

Objective We describe a novel human–machine interface for the control of a two-dimensional (2D) computer cursor using four inertial measurement units (IMUs) placed on the user’s upper-body. Approach A calibration paradigm where human subjects follow a cursor with their body as if they were controlling it with their shoulders generates a map between shoulder motions and cursor kinematics. This map is used in a Kalman filter to estimate the desired cursor coordinates from upper-body motions. We compared cursor control performance in a centre-out reaching task performed by subjects using different amounts of information from the IMUs to control the 2D cursor. Main results Our results indicate that taking advantage of the redundancy of the signals from the IMUs improved overall performance. Our work also demonstrates the potential of non-invasive IMU-based body–machine interface systems as an alternative or complement to brain–machine interfaces for accomplishing cursor control in 2D space. Significance The present study may serve as a platform for people with high-tetraplegia to control assistive devices such as powered wheelchairs using a joystick. PMID:25242561

Effect of participating in Taiwan Quality Indicator Project on hospital efficiency in Taiwan.

PubMed

Chu, Hsuan-Lien; Wang, Chen-Chin; Shiu, Shu Fen

2009-01-01

To examine the effect of participating in Taiwan Quality Indicator Project (TQIP) on hospital efficiency and investigate why hospitals participate in TQIP. Our sample consists of 417 private not-for-profit hospitals in Taiwan during the 2001-2007 period. A simultaneous-equation model was performed to examine if hospitals that participated in TQIP were more efficient than hospitals that did not and investigate which variables affected the probabilities of hospitals' participation in the project. Our findings indicate that participating hospitals are more efficient than hospitals not participating in TQIP. In addition, hospital efficiency, hospital size, teaching status, and hospital age are positively related to participation in the project. These empirical results can be used as supporting evidence of success in improving performance through creating quality for hospitals that have participated in the project and offer insights into the value and strengths of the project. In addition, in recent years, reimbursement systems worldwide have partly moved payment methods to a pay-for-performance mechanism. In an attempt to control costs and improve quality, the policy makers should consider participating in Quality Indicator Project (QIP) as being one of the criteria to be reimbursed for performance.

Training Recurrent Neural Networks With the Levenberg-Marquardt Algorithm for Optimal Control of a Grid-Connected Converter.

PubMed

Fu, Xingang; Li, Shuhui; Fairbank, Michael; Wunsch, Donald C; Alonso, Eduardo

2015-09-01

This paper investigates how to train a recurrent neural network (RNN) using the Levenberg-Marquardt (LM) algorithm as well as how to implement optimal control of a grid-connected converter (GCC) using an RNN. To successfully and efficiently train an RNN using the LM algorithm, a new forward accumulation through time (FATT) algorithm is proposed to calculate the Jacobian matrix required by the LM algorithm. This paper explores how to incorporate FATT into the LM algorithm. The results show that the combination of the LM and FATT algorithms trains RNNs better than the conventional backpropagation through time algorithm. This paper presents an analytical study on the optimal control of GCCs, including theoretically ideal optimal and suboptimal controllers. To overcome the inapplicability of the optimal GCC controller under practical conditions, a new RNN controller with an improved input structure is proposed to approximate the ideal optimal controller. The performance of an ideal optimal controller and a well-trained RNN controller was compared in close to real-life power converter switching environments, demonstrating that the proposed RNN controller can achieve close to ideal optimal control performance even under low sampling rate conditions. The excellent performance of the proposed RNN controller under challenging and distorted system conditions further indicates the feasibility of using an RNN to approximate optimal control in practical applications.

The Comprehension of Familiar and Novel Metaphoric Meanings in Schizophrenia: A Pilot Study.

PubMed

Rapp, Alexander M; Felsenheimer, Anne K; Langohr, Karin; Klupp, Magdalena

2017-01-01

Miscomprehension of nonliteral ("figurative") language like metaphors, proverbs, idioms, and ironic expressions by patients with schizophrenia is a phenomenon mentioned already in historical psychiatric descriptions. However, it was only recently that studies did differentiate between novel and conventional metaphors, a factor that is known to influence the difficulty of comprehension in healthy subjects. Further, familiarity with stimuli is an important factor for comprehension, which was not recommended in utmost previous studies. In this study, 23 patients with DSM IV schizophrenia and 19 healthy control subjects performed a newly-developed German metaphor comprehension test with three types of stimuli: novel metaphors, conventional German metaphors, and meaningless statements. During the test procedure, participants indicated familiarity with the stimulus and then matched the meaning with one out of four given alternatives. Familiarity rankings did not significantly differ between patients and control subjects. However, on descriptive level, there was a tendency for healthy controls to be more familiar with conventional metaphors than schizophrenic patients. Further, comprehension of conventional and novel metaphors differed significantly between the groups, with higher performance in healthy controls. Considering only those metaphors that had been ranked as familiar, patients only revealed significant lower performance opposed to controls regarding novel metaphors, while they did not differ in conventional metaphors. Taken together, the results indicate that patients with schizophrenia might show an altered way of comprehension in novel metaphors, leading to more misunderstandings. However, their previously reported impairments in conventional metaphors might rather be due to a lack of familiarity with the stimuli-making conventional metaphors to novel metaphors in the individual case.

The Comprehension of Familiar and Novel Metaphoric Meanings in Schizophrenia: A Pilot Study

PubMed Central

Rapp, Alexander M.; Felsenheimer, Anne K.; Langohr, Karin; Klupp, Magdalena

2018-01-01

Miscomprehension of nonliteral (“figurative”) language like metaphors, proverbs, idioms, and ironic expressions by patients with schizophrenia is a phenomenon mentioned already in historical psychiatric descriptions. However, it was only recently that studies did differentiate between novel and conventional metaphors, a factor that is known to influence the difficulty of comprehension in healthy subjects. Further, familiarity with stimuli is an important factor for comprehension, which was not recommended in utmost previous studies. In this study, 23 patients with DSM IV schizophrenia and 19 healthy control subjects performed a newly-developed German metaphor comprehension test with three types of stimuli: novel metaphors, conventional German metaphors, and meaningless statements. During the test procedure, participants indicated familiarity with the stimulus and then matched the meaning with one out of four given alternatives. Familiarity rankings did not significantly differ between patients and control subjects. However, on descriptive level, there was a tendency for healthy controls to be more familiar with conventional metaphors than schizophrenic patients. Further, comprehension of conventional and novel metaphors differed significantly between the groups, with higher performance in healthy controls. Considering only those metaphors that had been ranked as familiar, patients only revealed significant lower performance opposed to controls regarding novel metaphors, while they did not differ in conventional metaphors. Taken together, the results indicate that patients with schizophrenia might show an altered way of comprehension in novel metaphors, leading to more misunderstandings. However, their previously reported impairments in conventional metaphors might rather be due to a lack of familiarity with the stimuli—making conventional metaphors to novel metaphors in the individual case. PMID:29354082

A case control study of association between cognition and functional capacity in schizophrenia.

PubMed

Narayanan, Sreelatha S; Bhatia, Triptish; Velligan, Dawn I; Nimgaonkar, Vishwajit L; Deshpande, Smita N

2015-12-01

Cognitive functions are important prognostic factors for schizophrenia (SZ), while ability to perform activities of daily living are important measures of functional capacity. The relationship between cognition and functional capacity has not been tested extensively in India. To compare persons with SZ with controls on measures of cognition and functional capacity, and evaluate correlations between cognitive performance and functional capacity. Schizophrenia outpatients and controls without psychiatric illness (DSM IV) who completed the MATRICS Consensus Cognitive Battery and Functional Assessment Battery comprised of two tests from University of California San Diego (UCSD) Performance Based Skill Assessment (UPSA), one Test of Adaptive Behavior in Schizophrenia (TABS) and one test from University of California San Diego Performance Based Skill Assessment Brief edition (UPSA-B). Cognitive and functional domains were examined using regression analyses, with relevant covariates. Cases (N=51) though younger, were more educated than controls (N=41). Adjusting for education, controls performed better than cases in 3/7 cognitive and 4/5 domains of functional capacity but similarly in 'household management'. Among both cases and controls, cognitive measures of verbal learning and speed of processing overlapped with functional capacity (3 domains). Working memory was associated with one functional domain. Consistent with other studies, Indian patients with schizophrenia performed worse than controls on several domains of cognition and functional capacity; these domains were correlated. Speed of processing and verbal learning are most frequently associated with functional capacity indices and should be targeted to improve skills of daily living among persons with SZ. Copyright © 2015. Published by Elsevier B.V.

Vagal and sympathetic activity in burnouts during a mentally demanding workday.

PubMed

Zanstra, Ydwine J; Schellekens, Jan M H; Schaap, Cas; Kooistra, Libbe

2006-01-01

We study differences in task performance and related sympathetic-vagal reaction patterns between burnouts and controls during a mentally demanding workday. Thirty-nine adults with burnout and 40 healthy controls performed mental tasks during a simulated workday. At pretest, just before lunch (lunch test) and at the end of the day (posttest), a Stroop color word task was administered as a probe task. Efficiency (the relation between performance and effort during the probe task), performance (reaction time and errors), and effort (self-report) were measured, as well as cardiovascular indices of sympathetic (blood pressure) and vagal (respiratory sinus arrhythmia) activity. Performance and effort investment of both burnouts and controls did not differ during pretest. As the day progressed the performance of controls improved more than the performance of burnouts. Moreover, the control group showed a decrease of blood pressure in response to mental task demands, a decrease in respiratory sinus arrhythmia activity, and no change in experienced effort. In the burnout group, no change could be demonstrated in blood pressure, suggesting a sympathetic predominance in the sympathetic-vagal balance. Burnouts experienced an increase in effort and were more tired at the end of the workday. Burnouts and healthy controls differ in their pattern of sympathetic-vagal activity only after long-lasting work demands. Findings give limited support to Porges's view that in healthy subjects, the vagal system is more responsive to challenging task situations than in chronically stressed individuals. The distinction between two phases in the burnout on the basis of behavioral and physiological characteristics is discussed.

Structural Hippocampal Anomalies in a Schizophrenia Population Correlate with Navigation Performance on a Wayfinding Task

PubMed Central

Ledoux, Andrée-Anne; Boyer, Patrice; Phillips, Jennifer L.; Labelle, Alain; Smith, Andra; Bohbot, Véronique D.

2014-01-01

Episodic memory, related to the hippocampus, has been found to be impaired in schizophrenia. Further, hippocampal anomalies have also been observed in schizophrenia. This study investigated whether average hippocampal gray matter (GM) would differentiate performance on a hippocampus-dependent memory task in patients with schizophrenia and healthy controls. Twenty-one patients with schizophrenia and 22 control participants were scanned with an MRI while being tested on a wayfinding task in a virtual town (e.g., find the grocery store from the school). Regressions were performed for both groups individually and together using GM and performance on the wayfinding task. Results indicate that controls successfully completed the task more often than patients, took less time, and made fewer errors. Additionally, controls had significantly more hippocampal GM than patients. Poor performance was associated with a GM decrease in the right hippocampus for both groups. Within group regressions found an association between right hippocampi GM and performance in controls and an association between the left hippocampi GM and performance in patients. A second analysis revealed that different anatomical GM regions, known to be associated with the hippocampus, such as the parahippocampal cortex, amygdala, medial, and orbital prefrontal cortices, covaried with the hippocampus in the control group. Interestingly, the cuneus and cingulate gyrus also covaried with the hippocampus in the patient group but the orbital frontal cortex did not, supporting the hypothesis of impaired connectivity between the hippocampus and the frontal cortex in schizophrenia. These results present important implications for creating intervention programs aimed at measuring functional and structural changes in the hippocampus in schizophrenia. PMID:24672451

Structural hippocampal anomalies in a schizophrenia population correlate with navigation performance on a wayfinding task.

PubMed

Ledoux, Andrée-Anne; Boyer, Patrice; Phillips, Jennifer L; Labelle, Alain; Smith, Andra; Bohbot, Véronique D

2014-01-01

Episodic memory, related to the hippocampus, has been found to be impaired in schizophrenia. Further, hippocampal anomalies have also been observed in schizophrenia. This study investigated whether average hippocampal gray matter (GM) would differentiate performance on a hippocampus-dependent memory task in patients with schizophrenia and healthy controls. Twenty-one patients with schizophrenia and 22 control participants were scanned with an MRI while being tested on a wayfinding task in a virtual town (e.g., find the grocery store from the school). Regressions were performed for both groups individually and together using GM and performance on the wayfinding task. Results indicate that controls successfully completed the task more often than patients, took less time, and made fewer errors. Additionally, controls had significantly more hippocampal GM than patients. Poor performance was associated with a GM decrease in the right hippocampus for both groups. Within group regressions found an association between right hippocampi GM and performance in controls and an association between the left hippocampi GM and performance in patients. A second analysis revealed that different anatomical GM regions, known to be associated with the hippocampus, such as the parahippocampal cortex, amygdala, medial, and orbital prefrontal cortices, covaried with the hippocampus in the control group. Interestingly, the cuneus and cingulate gyrus also covaried with the hippocampus in the patient group but the orbital frontal cortex did not, supporting the hypothesis of impaired connectivity between the hippocampus and the frontal cortex in schizophrenia. These results present important implications for creating intervention programs aimed at measuring functional and structural changes in the hippocampus in schizophrenia.

Developmental hearing loss impedes auditory task learning and performance in gerbils

PubMed Central

von Trapp, Gardiner; Aloni, Ishita; Young, Stephen; Semple, Malcolm N.; Sanes, Dan H.

2016-01-01

The consequences of developmental hearing loss have been reported to include both sensory and cognitive deficits. To investigate these issues in a non-human model, auditory learning and asymptotic psychometric performance were compared between normal hearing (NH) adult gerbils and those reared with conductive hearing loss (CHL). At postnatal day 10, before ear canal opening, gerbil pups underwent bilateral malleus removal to induce a permanent CHL. Both CHL and control animals were trained to approach a water spout upon presentation of a target (Go stimuli), and withhold for foils (Nogo stimuli). To assess the rate of task acquisition and asymptotic performance, animals were tested on an amplitude modulation (AM) rate discrimination task. Behavioral performance was calculated using a signal detection theory framework. Animals reared with developmental CHL displayed a slower rate of task acquisition for AM discrimination task. Slower acquisition was explained by an impaired ability to generalize to newly introduced stimuli, as compared to controls. Measurement of discrimination thresholds across consecutive testing blocks revealed that CHL animals required a greater number of testing sessions to reach asymptotic threshold values, as compared to controls. However, with sufficient training, CHL animals approached control performance. These results indicate that a sensory impediment can delay auditory learning, and increase the risk of poor performance on a temporal task. PMID:27746215

Learning-based traffic signal control algorithms with neighborhood information sharing: An application for sustainable mobility

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

Aziz, H. M. Abdul; Zhu, Feng; Ukkusuri, Satish V.

Here, this research applies R-Markov Average Reward Technique based reinforcement learning (RL) algorithm, namely RMART, for vehicular signal control problem leveraging information sharing among signal controllers in connected vehicle environment. We implemented the algorithm in a network of 18 signalized intersections and compare the performance of RMART with fixed, adaptive, and variants of the RL schemes. Results show significant improvement in system performance for RMART algorithm with information sharing over both traditional fixed signal timing plans and real time adaptive control schemes. Additionally, the comparison with reinforcement learning algorithms including Q learning and SARSA indicate that RMART performs better atmore » higher congestion levels. Further, a multi-reward structure is proposed that dynamically adjusts the reward function with varying congestion states at the intersection. Finally, the results from test networks show significant reduction in emissions (CO, CO 2, NO x, VOC, PM 10) when RL algorithms are implemented compared to fixed signal timings and adaptive schemes.« less

Soft sensor based composition estimation and controller design for an ideal reactive distillation column.

PubMed

Vijaya Raghavan, S R; Radhakrishnan, T K; Srinivasan, K

2011-01-01

In this research work, the authors have presented the design and implementation of a recurrent neural network (RNN) based inferential state estimation scheme for an ideal reactive distillation column. Decentralized PI controllers are designed and implemented. The reactive distillation process is controlled by controlling the composition which has been estimated from the available temperature measurements using a type of RNN called Time Delayed Neural Network (TDNN). The performance of the RNN based state estimation scheme under both open loop and closed loop have been compared with a standard Extended Kalman filter (EKF) and a Feed forward Neural Network (FNN). The online training/correction has been done for both RNN and FNN schemes for every ten minutes whenever new un-trained measurements are available from a conventional composition analyzer. The performance of RNN shows better state estimation capability as compared to other state estimation schemes in terms of qualitative and quantitative performance indices. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

Flexible and polarization-controllable diffusion metasurface with optical transparency

NASA Astrophysics Data System (ADS)

Zhuang, Yaqiang; Wang, Guangming; Liang, Jiangang; Cai, Tong; Guo, Wenlong; Zhang, Qingfeng

2017-11-01

In this paper, a novel coding metasurface is proposed to realize polarization-controllable diffusion scattering. The anisotropic Jerusalem-cross unit cell is employed as the basic coding element due to its polarization-dependent phase response. The isotropic random coding sequence is firstly designed to obtain diffusion scattering, and the anisotropic random coding sequence is subsequently realized by adding different periodic coding sequences to the original isotropic one along different directions. For demonstration, we designed and fabricated a flexible polarization-controllable diffusion metasurface (PCDM) with both chessboard diffusion and hedge diffusion under different polarizations. The specular scattering reduction performance of the anisotropic metasurface is better than the isotropic one because the scattered energies are redirected away from the specular reflection direction. For potential applications, the flexible PCDM wrapped around a cylinder structure is investigated and tested for polarization-controllable diffusion scattering. The numerical and experimental results coincide well, indicating anisotropic low scatterings with comparable performances. This paper provides an alternative approach for designing high-performance, flexible, low-scattering platforms.

Validity of the Factor Structure of Conners' CPT

ERIC Educational Resources Information Center

Egeland, Jens; Kovalik-Gran, Iwona

2010-01-01

Objective: A previous factor analysis of the Conners' Continuous Performance Test (CCPT) indicates that the test measures 5 sub-functions of attention, namely "focused attention," "hyperactivity/impulsivity," "sustained attention," "vigilance," and "change in control." The present study further…

Increased fusiform area activation in schizophrenia during processing of spatial frequency-degraded faces, as revealed by fMRI.

PubMed

Silverstein, S M; All, S D; Kasi, R; Berten, S; Essex, B; Lathrop, K L; Little, D M

2010-07-01

People with schizophrenia demonstrate perceptual organization impairments, and these are thought to contribute to their face processing difficulties. We examined the neural substrates of emotionally neutral face processing in schizophrenia by investigating neural activity under three stimulus conditions: faces characterized by the full spectrum of spatial frequencies, faces with low spatial frequency information removed [high spatial frequency (HSF) condition], and faces with high spatial frequency information removed [low spatial frequency (LSF) condition]. Face perception in the HSF condition is more reliant on local feature processing whereas perception in the LSF condition requires greater reliance on global form processing. Past studies of perceptual organization in schizophrenia indicate that patients perform relatively more poorly with degraded stimuli but also that, when global information is absent, patients may perform better than controls because of their relatively increased ability to initially process individual features. Therefore, we hypothesized that people with schizophrenia (n=14) would demonstrate greater face processing difficulties than controls (n=13) in the LSF condition, whereas they would demonstrate a smaller difference or superior performance in the HSF condition. In a gender-discrimination task, behavioral data indicated high levels of accuracy for both groups, with a trend toward an interaction involving higher patient performance in the HSF condition and poorer patient performance in the LSF condition. Patients demonstrated greater activity in the fusiform gyrus compared to controls in both degraded conditions. These data suggest that impairments in basic integration abilities may be compensated for by relatively increased activity in this region.

Impaired verbal learning in forensic inpatients with Schizophrenia Spectrum Disorder.

PubMed

Corbett, Lasha; Karyadi, Kenny A; Kinney, Dominique; Nitch, Stephen R; Bayan, Stacey Marie; Williams, Mark

2018-01-01

The present study aimed to: (a) examine verbal learning performances among forensic inpatients diagnosed with Schizophrenia Spectrum Disorder (SSD); and (b) compare verbal learning performances among forensic SSD inpatients, SSD outpatients, and a small control sample. Participants included forensic SSD inpatients (n = 71), SSD outpatients (n = 305; see Stone et al.), and a control sample from the California Verbal Learning Test-II (CVLT-II) manual (n = 78; see Delis, Kramer, Kaplan, & Ober). Five verbal learning outcomes were measured using the CVLT-II. The average forensic SSD inpatients performed 1 to 1.5 standard deviations below the mean across the five verbal learning outcomes, many of whom (26.8% to 36.6%) performed in the impaired range across the five outcomes. Forensic SSD inpatients performed significantly lower than the SSD outpatients on three verbal learning outcomes and significantly lower than healthy controls on all five verbal learning outcomes. Results indicated forensically committed SSD inpatients have diminished verbal learning performances. Study findings could help define normative verbal learning performances in different types of SSD patients, may guide the development of compensatory strategies for verbal learning deficits, and could subsequently lead to more successful clinical outcomes in this population.

Effects of spatially displaced feedback on remote manipulation tasks

NASA Technical Reports Server (NTRS)

Manahan, Meera K.; Stuart, Mark A.; Bierschwale, John M.; Hwang, Ellen Y.; Legendre, A. J.

1992-01-01

Several studies have been performed to determine the effects on computer and direct manipulation task performance when viewing conditions are spatially displaced. Whether results from these studies can be directly applied to remote manipulation tasks is quenstionable. The objective of this evaluation was to determine the effects of reversed, inverted, and inverted/reversed views on remote manipulation task performance using two 3-Degree of Freedom (DOF) hand controllers and a replica position hand controller. Results showed that trials using the inverted viewing condition showed the worst performance, followed by the inverted/reversed view and the reversed view when using the 2x3 DOF. However, these differences were not significant. The inverted and inverted/reversed viewing conditions were significantly worse than the normal and reversed viewing conditions when using the Kraft Replica. A second evaluation was conducted in which additional trials were performed with each viewing condition to determine the long term effects of spatially displaced views on task performance for the hand controllers. Results of the second evaluation indicated that there was more of a difference in performance between the perturbed viewing conditions and the normal viewing condition with the Kraft Replica than with the 2x3 DOF.

Rule induction performance in amnestic mild cognitive impairment and Alzheimer's dementia: examining the role of simple and biconditional rule learning processes.

PubMed

Oosterman, Joukje M; Heringa, Sophie M; Kessels, Roy P C; Biessels, Geert Jan; Koek, Huiberdina L; Maes, Joseph H R; van den Berg, Esther

2017-04-01

Rule induction tests such as the Wisconsin Card Sorting Test require executive control processes, but also the learning and memorization of simple stimulus-response rules. In this study, we examined the contribution of diminished learning and memorization of simple rules to complex rule induction test performance in patients with amnestic mild cognitive impairment (aMCI) or Alzheimer's dementia (AD). Twenty-six aMCI patients, 39 AD patients, and 32 control participants were included. A task was used in which the memory load and the complexity of the rules were independently manipulated. This task consisted of three conditions: a simple two-rule learning condition (Condition 1), a simple four-rule learning condition (inducing an increase in memory load, Condition 2), and a complex biconditional four-rule learning condition-inducing an increase in complexity and, hence, executive control load (Condition 3). Performance of AD patients declined disproportionately when the number of simple rules that had to be memorized increased (from Condition 1 to 2). An additional increment in complexity (from Condition 2 to 3) did not, however, disproportionately affect performance of the patients. Performance of the aMCI patients did not differ from that of the control participants. In the patient group, correlation analysis showed that memory performance correlated with Condition 1 performance, whereas executive task performance correlated with Condition 2 performance. These results indicate that the reduced learning and memorization of underlying task rules explains a significant part of the diminished complex rule induction performance commonly reported in AD, although results from the correlation analysis suggest involvement of executive control functions as well. Taken together, these findings suggest that care is needed when interpreting rule induction task performance in terms of executive function deficits in these patients.

Effects of ethanol on Pavlovian autoshaping in rats.

PubMed

Tomie, A; Cunha, C; Mosakowski, E M; Quartarolo, N M; Pohorecky, L A; Benjamin, D

1998-09-01

Approach responses, consummatory behaviors, and directed motor responses maintained by food reward resemble autoshaping CRs and are increased by lower doses of ethanol. This study evaluated the effects of presession i.p. injections of ethanol doses (0.00, 0.25, 0.50, 0.70. or 1.00 g/kg) on the acquisition of lever-press autoshaping CR performance in groups of male Long-Evans hooded rats. Paired groups received 15 daily sessions of Pavlovian autoshaping procedures, wherein the insertion of a retractable lever for 5 s (CS) was followed by the response-independent presentation of food (US). Ethanol facilitated lever-press autoshaping CR acquisition, as revealed by dose-related increases in the number of trials on which CRs were performed. The form of the dose-effect curve was inverted U-shaped with maximal responding induced during sessions 1-5 by the 0.70 g/kg ethanol dose. A similar dose-effect curve was observed during sessions 11-15, revealing that the effects of ethanol on autoshaping CR performance were relatively stable. A pseudoconditioning control group injected presession with 0.50 g/kg ethanol received training wherein the food US was presented randomly with respect to the lever CS. Few lever-presses were performed by the Random 0.50 group, indicating that ethanol's effects on autoshaping CR acquisition and maintenance observed in the Paired 0.50 group were not due to its psychomotor activating effects. A non-injection control group performed more autoshaping CRs than did the control group injected presession with saline, indicating that daily presession i.p. injections per se suppress autoshaping CR performance. Results reveal that low doses of ethanol enhance Pavlovian conditioning of directed motor and consummatory-like responding maintained by food reward. Implications for autoshaping accounts of impulsivity and drug abuse are considered.

Vehicle automation: a remedy for driver stress?

PubMed

Funke, G; Matthews, G; Warm, J S; Emo, A K

2007-08-01

The present study addressed the effects of stress, vehicle automation and subjective state on driver performance and mood in a simulated driving task. A total of 168 college students participated. Participants in the stress-induction condition completed a 'winter' drive, which included periodic loss of control episodes. Participants in the no-stress-induction condition were not exposed to loss of control. An additional, independent manipulation of vehicle speed was also conducted, consisting of two control conditions requiring manual speed regulation and a third in which vehicle speed was automatically regulated by the simulation. Stress and automation both influenced subjective distress, but the two factors did not interact. Driver performance data indicated that vehicle automation impacted performance similarly in the stress and no-stress conditions. Individual differences in subjective stress response and performance were also investigated. Resource theory provides a framework that partially but not completely explains the relationship between vehicle automation and driver stress. Implications for driver workload, safety and training are discussed.

Effect of magnetic therapy on selected physical performances.

PubMed

Schall, David M; Ishee, Jimmy H; Titlow, Larry W

2003-05-01

The purpose of this study was to investigate the effects of magnetic therapy in the form of shoe insoles on vertical jump, bench squat, 40-yd dash, and a soccer-specific fitness test performance. Subjects were 14 collegiate male soccer players who were pretested, retested 3 weeks later, and then placed into a double-blind control or treatment group using a matching procedure. The control group received magnetic shoe insoles with a rating of 125 gauss, and the treatment group received insoles with a rating of 600 gauss. Subjects wore the insoles during practice and games for 7 weeks and were then retested. Results indicated significant differences among test scores during the 3 time periods but not between the treatment and control groups. There was a decline in 40-yd dash performance from the initial evaluation (5.10 seconds) to the final evaluation (5.08 seconds). There were no other significant differences. Within the limitations of the study, magnetic therapy did not improve physical performance.

Twelve-Week Exercise Influences Memory Complaint but not Memory Performance in Older Adults: A Randomized Controlled Study.

PubMed

Iuliano, Enzo; Fiorilli, Giovanni; Aquino, Giovanna; Di Costanzo, Alfonso; Calcagno, Giuseppe; di Cagno, Alessandra

2017-10-01

This study aimed to evaluate the effects of different types of exercise on memory performance and memory complaint after a 12-week intervention. Eighty community-dwelling volunteers, aged 66.96 ± 11.73 years, were randomly divided into four groups: resistance, cardiovascular, postural, and control groups (20 participants for each group). All participants were tested for their cognitive functions before and after their respective 12-week intervention using Rey memory words test, Prose memory test, and Memory Complaint Questionnaire (MAC-Q). Statistical analysis showed that the three experimental groups significantly improved MAC-Q scores in comparison with the control group (p < .05). The variation of MAC-Q scores and the variations of Rey and Prose memory tests scores were not correlated. These results indicate that the 12-week interventions exclusively influenced memory complaint but not memory performance. Further investigations are needed to understand the relation between memory complaint and memory performance, and the factors that can influence this relationship.

Controllable synthesis of rice-shape Alq3 nanoparticles with single crystal structure

NASA Astrophysics Data System (ADS)

Xie, Wanfeng; Fan, Jihui; Song, Hui; Jiang, Feng; Yuan, Huimin; Wei, Zhixian; Ji, Ziwu; Pang, Zhiyong; Han, Shenghao

2016-10-01

We report the controllable growth of rice-shape nanoparticles of Alq3 by an extremely facile self-assembly approach. Possible mechanisms have been proposed to interpret the formation and controlled process of the single crystal nanoparticles. The field-emission performances (turn-on field 7 V μm-1, maximum current density 2.9 mA cm-2) indicate the potential application on miniaturized nano-optoelectronics devices of Alq3-based. This facile method can potentially be used for the controlled synthesis of other functional complexes and organic nanostructures.

Using Publicly Reported Nursing-Sensitive Screening Indicators to Measure Hospital Performance: The Netherlands Experience in 2011.

PubMed

Stalpers, Dewi; van der Linden, Dimitri; Kaljouw, Marian J; Schuurmans, Marieke J

2016-01-01

Deliberate screening allows detection of health risks that are otherwise not noticeable and allows expedient intervention to minimize complications and optimize outcomes, especially during critical events like hospitalization. Little research has evaluated the usefulness of screening performance and outcome indicators as measures to differentiate nursing quality, although policymakers are using them to benchmark hospitals. The aims of this study were to examine hospital performance based on nursing-sensitive screening indicators and to assess associations with hospital characteristics and nursing-sensitive outcomes for patients. A secondary use of nursing-sensitive data from the Dutch Health Care Inspectorate was performed, including the mandatory screening and outcome indicators related to delirium, malnutrition, pain and pressure ulcers. The sample consisted of all 93 hospitals in the Netherlands in 2011. High- and low-performing hospitals were determined based on the overall proportion of screened patients. Descriptive statistics and analysis of variance were used to examine screening performances in relation to hospital characteristics and nursing-sensitive outcomes. Over all hospitals, the average screening rates ranged from 59% (delirium) to 94% (pain). Organizational characteristics were not different in high- and low-performing hospitals. The hospitals with the best overall screening performances had significantly better results regarding protein intake within malnourished patients (p < .01). For mortality, marginal significant effects did not remain after controlling for organizational structures. No associations were found with prevalence of pressure ulcers and patient self-reported pain scores. The screening for patient risks is an important nursing task. Our findings suggest that nursing-sensitive screening indicators may be relevant measures for benchmarking nursing quality in hospitals. Time-trend studies are required to support our findings and to further investigate relations with nursing-sensitive outcomes.

Direct model reference adaptive control of robotic arms

NASA Technical Reports Server (NTRS)

Kaufman, Howard; Swift, David C.; Cummings, Steven T.; Shankey, Jeffrey R.

1993-01-01

The results of controlling A PUMA 560 Robotic Manipulator and the NASA shuttle Remote Manipulator System (RMS) using a Command Generator Tracker (CGT) based Model Reference Adaptive Controller (DMRAC) are presented. Initially, the DMRAC algorithm was run in simulation using a detailed dynamic model of the PUMA 560. The algorithm was tuned on the simulation and then used to control the manipulator using minimum jerk trajectories as the desired reference inputs. The ability to track a trajectory in the presence of load changes was also investigated in the simulation. Satisfactory performance was achieved in both simulation and on the actual robot. The obtained responses showed that the algorithm was robust in the presence of sudden load changes. Because these results indicate that the DMRAC algorithm can indeed be successfully applied to the control of robotic manipulators, additional testing was performed to validate the applicability of DMRAC to simulated dynamics of the shuttle RMS.

Experimental study of adaptive pointing and tracking for large flexible space structures

NASA Technical Reports Server (NTRS)

Boussalis, D.; Bayard, D. S.; Ih, C.; Wang, S. J.; Ahmed, A.

1991-01-01

This paper describes an experimental study of adaptive pointing and tracking control for flexible spacecraft conducted on a complex ground experiment facility. The algorithm used in this study is based on a multivariable direct model reference adaptive control law. Several experimental validation studies were performed earlier using this algorithm for vibration damping and robust regulation, with excellent results. The current work extends previous studies by addressing the pointing and tracking problem. As is consistent with an adaptive control framework, the plant is assumed to be poorly known to the extent that only system level knowledge of its dynamics is available. Explicit bounds on the steady-state pointing error are derived as functions of the adaptive controller design parameters. It is shown that good tracking performance can be achieved in an experimental setting by adjusting adaptive controller design weightings according to the guidelines indicated by the analytical expressions for the error.

Solar dynamic modules for Space Station Freedom: The relationship between fine-pointing control and thermal loading of the aperture plate

NASA Technical Reports Server (NTRS)

Quinn, Roger D.; Kerslake, Thomas W.

1992-01-01

Dynamic simulations of Space Station Freedom (SSF) configured with solar dynamic (SD) power modules were performed. The structure was subjected to Space Shuttle docking disturbances, while being controlled with a 'natural' vibration and tracking control approach. Three control cases were investigated for the purpose of investigating the relationship between actuator effort, SD pointing, and thermal loading on the receiver aperture plate. Transient, one-dimensional heat transfer analyses were performed to conservatively predict temperatures of the multi-layered receiver aperture plate assembly and thermal stresses in its shield layer. Results indicate that the proposed aperture plate is tolerant of concentrated flux impingement during short-lived structural disturbances. Pointing requirements may be loosened and the requirement control torques lessened from that previously specified. Downsizing and simplifying the joint drive system should result in a considerable savings mass.

Response of ponderosa pine plantations to competing vegetation control in Northern California, USA: A meta- analysis

Treesearch

Jianwei Zhang; Robert Powers; William Oliver; Young David

2013-01-01

A meta-analysis was performed to determine response of stand basal area growth to competing vegetation control (CVC) in ponderosa pine (Pinus ponderosa) plantations grown at 29 sites across northern California. These studies were installed during the last 50 years on site indices from 11 to 35 m at 50 years and often included other treatments...

Design, Fabrication, and Modeling of a Novel Dual-Axis Control Input PZT Gyroscope.

PubMed

Chang, Cheng-Yang; Chen, Tsung-Lin

2017-10-31

Conventional gyroscopes are equipped with a single-axis control input, limiting their performance. Although researchers have proposed control algorithms with dual-axis control inputs to improve gyroscope performance, most have verified the control algorithms through numerical simulations because they lacked practical devices with dual-axis control inputs. The aim of this study was to design a piezoelectric gyroscope equipped with a dual-axis control input so that researchers may experimentally verify those control algorithms in future. Designing a piezoelectric gyroscope with a dual-axis control input is more difficult than designing a conventional gyroscope because the control input must be effective over a broad frequency range to compensate for imperfections, and the multiple mode shapes in flexural deformations complicate the relation between flexural deformation and the proof mass position. This study solved these problems by using a lead zirconate titanate (PZT) material, introducing additional electrodes for shielding, developing an optimal electrode pattern, and performing calibrations of undesired couplings. The results indicated that the fabricated device could be operated at 5.5±1 kHz to perform dual-axis actuations and position measurements. The calibration of the fabricated device was completed by system identifications of a new dynamic model including gyroscopic motions, electromechanical coupling, mechanical coupling, electrostatic coupling, and capacitive output impedance. Finally, without the assistance of control algorithms, the "open loop sensitivity" of the fabricated gyroscope was 1.82 μV/deg/s with a nonlinearity of 9.5% full-scale output. This sensitivity is comparable with those of other PZT gyroscopes with single-axis control inputs.

Biological risk indicators for recurrent non-specific low back pain in adolescents.

PubMed

Jones, M A; Stratton, G; Reilly, T; Unnithan, V B

2005-03-01

A matched case-control study was carried out to evaluate biological risk indicators for recurrent non-specific low back pain in adolescents. Adolescents with recurrent non-specific low back pain (symptomatic; n = 28; mean (SD) age 14.9 (0.7) years) and matched controls (asymptomatic; n = 28; age 14.9 (0.7) years) with no history of non-specific low back pain participated. Measures of stature, mass, sitting height, sexual maturity (Tanner self assessment), lateral flexion of the spine, lumbar sagittal plane mobility (modified Schober), hip range of motion (Leighton flexometer), back and hamstring flexibility (sit and reach), and trunk muscle endurance (number of sit ups) were performed using standardised procedures with established reliability. Backward stepwise logistic regression analysis was performed, with the presence/absence of recurrent low back pain as the dependent variable and the biological measures as the independent variables. Hip range of motion, trunk muscle endurance, lumbar sagittal plane mobility, and lateral flexion of the spine were identified as significant risk indicators of recurrent low back pain (p<0.05). Follow up analysis indicated that symptomatic subjects had significantly reduced lateral flexion of the spine, lumbar sagittal plane mobility, and trunk muscle endurance (p<0.05). Hip range of motion, abdominal muscle endurance, lumbar flexibility, and lateral flexion of the spine were risk indicators for recurrent non-specific low back pain in a group of adolescents. These risk indicators identify the potential for exercise as a primary or secondary prevention method.

Telerobotic control of the seven-degree-of-freedom CESAR manipulator

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

Babcock, S.M.; Dubey, R.V.; Euler, J.A.

1988-01-01

The application of a computationally efficient kinematic control scheme for manipulators with redundant degrees of freedom to the unilateral telerobotic control of seven-degree-of-freedom manipulator (CESARM) at the Oak Ridge National Laboratory Center for Engineering Systems Advanced Research is presented. The kinematic control scheme uses a gradient projection optimization method, which eliminates that need to determine the generalized inverse of the Jacobian when solving for joint velocities, given Cartesian end-effector velocities. A six-degree-of-freedom (nonreplica) master controller is used. Performance indices for redundancy resolution are discussed. 5 ref., 6 figs.

Automatic control algorithm effects on energy production

NASA Technical Reports Server (NTRS)

Mcnerney, G. M.

1981-01-01

A computer model was developed using actual wind time series and turbine performance data to simulate the power produced by the Sandia 17-m VAWT operating in automatic control. The model was used to investigate the influence of starting algorithms on annual energy production. The results indicate that, depending on turbine and local wind characteristics, a bad choice of a control algorithm can significantly reduce overall energy production. The model can be used to select control algorithms and threshold parameters that maximize long term energy production. The results from local site and turbine characteristics were generalized to obtain general guidelines for control algorithm design.

Bilingualism and Musicianship Enhance Cognitive Control

PubMed Central

2016-01-01

Learning how to speak a second language (i.e., becoming a bilingual) and learning how to play a musical instrument (i.e., becoming a musician) are both thought to increase executive control through experience-dependent plasticity. However, evidence supporting this effect is mixed for bilingualism and limited for musicianship. In addition, the combined effects of bilingualism and musicianship on executive control are unknown. To determine whether bilingualism, musicianship, and combined bilingualism and musicianship improve executive control, we tested 219 young adults belonging to one of four groups (bilinguals, musicians, bilingual musicians, and controls) on a nonlinguistic, nonmusical, visual-spatial Simon task that measured the ability to ignore an irrelevant and misinformative cue. Results revealed that bilinguals, musicians, and bilingual musicians showed an enhanced ability to ignore a distracting cue relative to controls, with similar levels of superior performance among bilinguals, musicians, and bilingual musicians. These results indicate that bilingualism and musicianship improve executive control and have implications for educational and rehabilitation programs that use music and foreign language instruction to boost cognitive performance. PMID:26819764

Finite State Machine with Adaptive Electromyogram (EMG) Feature Extraction to Drive Meal Assistance Robot

NASA Astrophysics Data System (ADS)

Zhang, Xiu; Wang, Xingyu; Wang, Bei; Sugi, Takenao; Nakamura, Masatoshi

Surface electromyogram (EMG) from elbow, wrist and hand has been widely used as an input of multifunction prostheses for many years. However, for patients with high-level limb deficiencies, muscle activities in upper-limbs are not strong enough to be used as control signals. In this paper, EMG from lower-limbs is acquired and applied to drive a meal assistance robot. An onset detection method with adaptive threshold based on EMG power is proposed to recognize different muscle contractions. Predefined control commands are output by finite state machine (FSM), and applied to operate the robot. The performance of EMG control is compared with joystick control by both objective and subjective indices. The results show that FSM provides the user with an easy-performing control strategy, which successfully operates robots with complicated control commands by limited muscle motions. The high accuracy and comfortableness of the EMG-control meal assistance robot make it feasible for users with upper limbs motor disabilities.

Knobology in use: an experimental evaluation of ergonomics recommendations.

PubMed

Overgård, Kjell Ivar; Fostervold, Knut Inge; Bjelland, Hans Vanhauwaert; Hoff, Thomas

2007-05-01

The scientific basis for ergonomics recommendations for controls has usually not been related to active goal-directed use. The present experiment tests how different knob sizes and torques affect operator performance. The task employed is to control a pointer by the use of a control knob, and is as such an experimentally defined goal-directed task relevant to machine systems in general. Duration of use, error associated with use (overshooting of the goal area) and movement reproduction were used as performance measures. Significant differences between knob sizes were found for movement reproduction. High torques led to less overshooting as opposed to low torques. The results from duration of use showed a tendency that the differences between knob sizes were reduced from the first iteration to the second iteration. The present results indicate that the ergonomically recommended ranges of knob sizes might differently affect operator performance.

Effectiveness of Small-Group Tutoring Interventions for Improving the Mathematical Problem-Solving Performance of Third-Grade Students with Mathematics Difficulties: A Randomized Experiment

ERIC Educational Resources Information Center

Jitendra, Asha K.; Dupuis, Danielle N.; Rodriguez, Michael C.

2012-01-01

The present research assessed the efficacy of two tutoring protocols for improving the mathematics outcomes of at-risk third-grade students. Results indicated that students in the schema-based instruction (SBI) group outperformed students in the control group on word problem solving performance after 30 hours of problem-solving experience, but the…

One-man, self-contained CO2 concentrating system

NASA Technical Reports Server (NTRS)

Wynveen, R. A.; Schubert, F. H.; Powell, J. D.

1972-01-01

A program to design, fabricate, and test a 1-man, self-contained, electrochemical CO2 concentrating system is described. The system was designed with electronic controls and instrumentation to regulate performance, to analyze and display performance trends, and to detect and isolate faults. Ground support accessories were included to provide power, fluids, and a Parametric Data Display allowing real time indication of operating status in engineering units.

POPEYE: A production rule-based model of multitask supervisory control (POPCORN)

NASA Technical Reports Server (NTRS)

Townsend, James T.; Kadlec, Helena; Kantowitz, Barry H.

1988-01-01

Recent studies of relationships between subjective ratings of mental workload, performance, and human operator and task characteristics have indicated that these relationships are quite complex. In order to study the various relationships and place subjective mental workload within a theoretical framework, we developed a production system model for the performance component of the complex supervisory task called POPCORN. The production system model is represented by a hierarchial structure of goals and subgoals, and the information flow is controlled by a set of condition-action rules. The implementation of this production system, called POPEYE, generates computer simulated data under different task difficulty conditions which are comparable to those of human operators performing the task. This model is the performance aspect of an overall dynamic psychological model which we are developing to examine and quantify relationships between performance and psychological aspects in a complex environment.

Particle size effect in porous film electrodes of ligand-modified graphene for enhanced supercapacitor performance

DOE PAGES

Jang, Gyoung Gug; Song, Bo; Moon, Kyoung-sik; ...

2017-04-17

Graphene-based electrodes for high performance supercapacitors are developed by taking advantage of particle size control, large mass loading, and surface functionalization of reduced graphene oxide (rGO) sheets. Two controlled sizes of graphene sheets (100 nm vs. 45 μm average lateral dimensions) were prepared to study two-electrode system performance. The nano-size graphenes led to the formation of mesoporous films, resulting in higher capacitance, better capacitance retension and lower equivalent series resistance (ESR), indicating better surface usability for diffusion and accessibility of electrolyte ions by shortening transport paths (compared with horizontally stacked films from micro-sized graphenes). For studies using an aqueous electrolyte,more » the maximum specific capacitance of nano-rGO film was 302 F/g (at 1 A/g with 4.3 mg/cm 2 of mass loading), which was ~2.4 times higher than micro-rGO film, and achieved a ~67% reduced ESR. With an organic electrolyte, the nano-rGO delivered ~4.2 times higher capacitance (115 F/g at 2 A/g with 4.3 mg/cm 2), 4.0 times lower IR drops, and an order-of-magnitude lower charge-transfer resistance with an energy density of 18.7 Wh/kg. Finally, the results of this work indicate that the size control of graphene sheet particles for film deposit electrodes can be a simple but effective approach to improve supercapacitor performance.« less

Effect of public symphysiodesis on pelvic development in the skeletally immature greyhound.

PubMed

Swainson, S W; Conzemius, M G; Riedesel, E A; Smith, G K; Riley, C B

2000-01-01

To evaluate the effect of pubic symphysiodesis (PS) on pelvic development in skeletally immature dogs. Prospective randomized clinical trial. Eight 4 month-old, sexually intact female Greyhounds. Initial PS was performed at 4 months of age using a powered stapling device. Because of failure of the initial surgery, a second PS was performed 1 month later by resecting the pubic symphysis with a rongeur followed by placement of handmade bone staples in four dogs. Sham PS was performed in four control dogs at 4 months of age. Pubic growth rate and pelvic development were evaluated using standard plane radiography and computed tomography. Specific measurements included acetabular ventroversion, Norberg angle, lateral center-edge angle, and pelvic inlet dimensions. Hip distraction indices were determined as well. PS at 4 months of age using a stapling device failed. Pubic symphysiodesis using hand made staples was successful at 5 months of age and did not result in any clinically significant intraoperative or postoperative complications. Pubic symphysiodesis markedly decreased pubic symphysis growth in the treatment group. Hip distraction indices and pelvic inlet circumference, area, and width significantly decreased in treated dogs compared to those in the control group. Acetabular ventroversion was significantly increased in treated dogs compared to those in the control group. PS decreases pelvic canal size, increases acetabular ventroversion, and does not appear to have any clinically significant complications. PS performed in skeletally immature dogs with hip dysplasia may provide an effect similar to a triple pelvic osteotomy and warrants further investigation.

Particle size effect in porous film electrodes of ligand-modified graphene for enhanced supercapacitor performance

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

Jang, Gyoung Gug; Song, Bo; Moon, Kyoung-sik

Graphene-based electrodes for high performance supercapacitors are developed by taking advantage of particle size control, large mass loading, and surface functionalization of reduced graphene oxide (rGO) sheets. Two controlled sizes of graphene sheets (100 nm vs. 45 μm average lateral dimensions) were prepared to study two-electrode system performance. The nano-size graphenes led to the formation of mesoporous films, resulting in higher capacitance, better capacitance retension and lower equivalent series resistance (ESR), indicating better surface usability for diffusion and accessibility of electrolyte ions by shortening transport paths (compared with horizontally stacked films from micro-sized graphenes). For studies using an aqueous electrolyte,more » the maximum specific capacitance of nano-rGO film was 302 F/g (at 1 A/g with 4.3 mg/cm 2 of mass loading), which was ~2.4 times higher than micro-rGO film, and achieved a ~67% reduced ESR. With an organic electrolyte, the nano-rGO delivered ~4.2 times higher capacitance (115 F/g at 2 A/g with 4.3 mg/cm 2), 4.0 times lower IR drops, and an order-of-magnitude lower charge-transfer resistance with an energy density of 18.7 Wh/kg. Finally, the results of this work indicate that the size control of graphene sheet particles for film deposit electrodes can be a simple but effective approach to improve supercapacitor performance.« less

Experienced stress produces inhibitory deficits in old adults' Flanker task performance: First evidence for lifetime stress effects beyond memory.

PubMed

Marshall, Amanda C; Cooper, Nicholas R; Geeraert, Nicolas

2016-01-01

Studies regarding aged individuals' performance on the Flanker task differ with respect to reporting impaired or intact executive control. Past work has explained this discrepancy by hypothesising that elderly individuals use increased top-down control mechanisms advantageous to Flanker performance. This study investigated this mechanism, focussing on cumulative experienced stress as a factor that may impact on its execution, thereby leading to impaired performance. Thirty elderly and thirty young participants completed a version of the Flanker task paired with electroencephalographic recordings of the alpha frequency, whose increased synchronisation indexes inhibitory processes. Among high stress elderly individuals, findings revealed a general slowing of reaction times for congruent and incongruent stimuli, which correlated with alpha desynchronisation for both stimulus categories. Results found high performing (low stress) elderly revealed neither a behavioural nor electrophysiological difference compared to young participants. Therefore, rather than impacting on top-down compensatory mechanisms, findings indicate that stress may affect elderly participants' inhibitory control in attentional and sensorimotor domains. Copyright © 2015 Elsevier B.V. All rights reserved.

Improving cylinder-type LiFePO4 battery performance via control of internal resistance

NASA Astrophysics Data System (ADS)

Purwanto, Agus; Jumari, Arif; Nizam, Muhammad; Widiyandari, Hendri; Sudaryanto; Deswita; Azmin Mohamad, Ahmad

2018-04-01

Strategies for controlling the internal resistance to improve battery performance were systematically investigated. Electrode densification of LiFePO4 cathodes significantly reduced the internal resistance of the prepared batteries. Densification by reduction to 31.25% of initial thickness resulted in optimal electrochemical performance of the prepared LiFePO4 batteries. The addition of KS 6 graphite material improved the conductivity of the cathodes, which was indicated by a lowering of the internal resistance. The internal resistance was decreased from 73 to 54 when the KS6/AB ratio was varied from 3 to 1. Another factor in controlling the internal resistance was the location of a welded aluminum tab in the cathode. The welding of an aluminum tab in a small gap in the cathode significantly reduced the internal resistance. Thus, three main factors can be performed during fabrication to reduce the internal resistance of a LiFePO4 battery: cathode densification, KS-6 graphite addition, and the arrangement of an aluminum tab welded to the cathode. By optimizing these factors, high-performance LFP batteries were produced.

Prediction of noise constrained optimum takeoff procedures

NASA Technical Reports Server (NTRS)

Padula, S. L.

1980-01-01

An optimization method is used to predict safe, maximum-performance takeoff procedures which satisfy noise constraints at multiple observer locations. The takeoff flight is represented by two-degree-of-freedom dynamical equations with aircraft angle-of-attack and engine power setting as control functions. The engine thrust, mass flow and noise source parameters are assumed to be given functions of the engine power setting and aircraft Mach number. Effective Perceived Noise Levels at the observers are treated as functionals of the control functions. The method is demonstrated by applying it to an Advanced Supersonic Transport aircraft design. The results indicate that automated takeoff procedures (continuously varying controls) can be used to significantly reduce community and certification noise without jeopardizing safety or degrading performance.

Dynamic performance of accommodating intraocular lenses in a negative feedback control system: a simulation-based study.

PubMed

Schor, Clifton M; Bharadwaj, Shrikant R; Burns, Christopher D

2007-07-01

A dynamic model of ocular accommodation is used to simulate the stability and dynamic performance of accommodating intraocular lenses (A-IOLs) that replace the hardened natural ocular lens that is unable to change focus. Accommodation simulations of an older eye with A-IOL materials having biomechanical properties of a younger eye illustrate overshoots and oscillations resulting from decreased visco-elasticity of the A-IOL. Stable dynamics of an A-IOL are restored by adaptation of phasic and tonic neural-control properties of accommodation. Simulations indicate that neural control must be recalibrated to avoid unstable dynamic accommodation with A-IOLs. An interactive web-model of A-IOL illustrating these properties is available at http://schorlab.berkeley.edu.

Real-time simulation of the TF30-P-3 turbofan engine using a hybrid computer

NASA Technical Reports Server (NTRS)

Szuch, J. R.; Bruton, W. M.

1974-01-01

A real-time, hybrid-computer simulation of the TF30-P-3 turbofan engine was developed. The simulation was primarily analog in nature but used the digital portion of the hybrid computer to perform bivariate function generation associated with the performance of the engine's rotating components. FORTRAN listings and analog patching diagrams are provided. The hybrid simulation was controlled by a digital computer programmed to simulate the engine's standard hydromechanical control. Both steady-state and dynamic data obtained from the digitally controlled engine simulation are presented. Hybrid simulation data are compared with data obtained from a digital simulation provided by the engine manufacturer. The comparisons indicate that the real-time hybrid simulation adequately matches the baseline digital simulation.

Visual scanning behavior and pilot workload

NASA Technical Reports Server (NTRS)

Harris, R. L., Sr.; Tole, J. R.; Stephens, A. T.; Ephrath, A. R.

1982-01-01

This paper describes an experimental paradigm and a set of results which demonstrate a relationship between the level of performance on a skilled man-machine control task, the skill of the operator, the level of mental difficulty induced by an additional task imposed on the basic control task, and visual scanning performance. During a constant, simulated piloting task, visual scanning of instruments was found to vary with the difficulty of a verbal mental loading task. The average dwell time of each fixation on the pilot's primary instrument increased with the estimated skill level of the pilots, with novices being affected by the loading task much more than experts. The results suggest that visual scanning of instruments in a controlled task may be an indicator of both workload and skill.

Indicators of suboptimal performance embedded in the Wechsler Memory Scale-Fourth Edition (WMS-IV).

PubMed

Bouman, Zita; Hendriks, Marc P H; Schmand, Ben A; Kessels, Roy P C; Aldenkamp, Albert P

2016-01-01

Recognition and visual working memory tasks from the Wechsler Memory Scale-Fourth Edition (WMS-IV) have previously been documented as useful indicators for suboptimal performance. The present study examined the clinical utility of the Dutch version of the WMS-IV (WMS-IV-NL) for the identification of suboptimal performance using an analogue study design. The patient group consisted of 59 mixed-etiology patients; the experimental malingerers were 50 healthy individuals who were asked to simulate cognitive impairment as a result of a traumatic brain injury; the last group consisted of 50 healthy controls who were instructed to put forth full effort. Experimental malingerers performed significantly lower on all WMS-IV-NL tasks than did the patients and healthy controls. A binary logistic regression analysis was performed on the experimental malingerers and the patients. The first model contained the visual working memory subtests (Spatial Addition and Symbol Span) and the recognition tasks of the following subtests: Logical Memory, Verbal Paired Associates, Designs, Visual Reproduction. The results showed an overall classification rate of 78.4%, and only Spatial Addition explained a significant amount of variation (p < .001). Subsequent logistic regression analysis and receiver operating characteristic (ROC) analysis supported the discriminatory power of the subtest Spatial Addition. A scaled score cutoff of <4 produced 93% specificity and 52% sensitivity for detection of suboptimal performance. The WMS-IV-NL Spatial Addition subtest may provide clinically useful information for the detection of suboptimal performance.

Does the therapy manual or the therapist matter most in treatment of obsessive-compulsive disorder? A randomized controlled trial of exposure with response or ritual prevention in 118 patients.

PubMed

van Oppen, Patricia; van Balkom, Anton J L M; Smit, Johannes H; Schuurmans, Josien; van Dyck, Richard; Emmelkamp, Paul M G

2010-09-01

The importance of the therapist's education and experience for the successful behavior treatment of obsessive-compulsive disorder (OCD) has not been investigated. Data on the relative effectiveness of self-controlled versus therapist-controlled in vivo exposure with response or ritual prevention (ERP) have yielded conflicting results. The present study compared the effectiveness of 4 different modes of delivery of ERP in a referred sample of OCD patients. Of the 146 eligible OCD outpatients, 118 patients enrolled in this randomized controlled trial and were randomly assigned to (1) therapist-controlled ERP performed by experienced behavior therapists; (2) therapist-controlled ERP performed by master's students of clinical psychology; (3) self-controlled ERP performed by experienced behavior therapists; and (4) self-controlled ERP performed by master's students of clinical psychology. This trial was performed from January 1999 to January 2005. Our analyses revealed no significant differences in clinical outcome between any of the different modes of delivery of ERP at posttreatment. The different ERP modes of delivery were associated with significant pretreatment to posttreatment improvement on all measurements, with large effect sizes on the primary outcome measure, the Yale-Brown Obsessive Compulsive Scale. Our results indicate that clinically inexperienced master's students with no postgraduate training can be as capable as experienced and certified behavior therapists in treating OCD patients, as long as therapists adhere to a standardized treatment manual and adequate training and supervision is provided. In contrast to other studies, we did not find a supposed benefit of therapist-controlled ERP versus self-controlled ERP in patients with OCD. www.trialregister.nl Identifier: NTR1444. © Copyright 2010 Physicians Postgraduate Press, Inc.

Towards a balanced performance measurement system in a public health care organization.

PubMed

Yuen, Peter P; Ng, Artie W

2012-01-01

This article attempts to devise an integrated performance measurement framework to assess the Hong Kong Hospital Authority (HA) management system by harnessing previous performance measurement systems. An integrated evaluative framework based on the balanced score card (BSC) was developed and applied using the case study method and longitudinal data to evaluate the HA's performance management system. The authors unveil evolving HA performance indicators (P1). Despite the HA staffs explicit quality emphasis, cost control remains the primary focus in their performance measurements. RESEARCH LHNITATIONS/IMPLICATIONS: Data used in this study are from secondary sources, disclosed mostly by HA staff. This study shows public sector staff often attach too much importance to cost control and easily measurable activities at the expense of quality and other less easily measurable attributes'. A balanced performance measurement system, linked to health targets, with a complementary budgeting process that supports pertinent resource allocation is yet to be implemented in Hong Kong's public hospitals.

Embedded control system for computerized franking machine

NASA Astrophysics Data System (ADS)

Shi, W. M.; Zhang, L. B.; Xu, F.; Zhan, H. W.

2007-12-01

This paper presents a novel control system for franking machine. A methodology for operating a franking machine using the functional controls consisting of connection, configuration and franking electromechanical drive is studied. A set of enabling technologies to synthesize postage management software architectures driven microprocessor-based embedded systems is proposed. The cryptographic algorithm that calculates mail items is analyzed to enhance the postal indicia accountability and security. The study indicated that the franking machine is reliability, performance and flexibility in printing mail items.

Difference in children's gross motor skills between two types of preschools.

PubMed

Chow, Bik C; Louie, Lobo H T

2013-02-01

The purpose of this study was to assess the influence of preschool type (public vs private) on motor skill performance in 239 (121 boys, 118 girls) preschool children ages 3 to 6.5 yr. Preschoolers were tested on 12 fundamental motor skills from the Test of Gross Motor Development-Second Edition and 11 anthropometrics (body height, weight, Body Mass Index, waist and hip girths, and body segment lengths). Analysis of variance controlled for anthropometrics and age indicated that children from private preschools performed better on locomotor skills than those from public preschools. However, no difference was found in object control skills. The results suggest that performance of locomotor skills by preschool children is affected by their schools' physical environment.

Development and assessment of national performance indicators for infection prevention and control and antimicrobial stewardship in European long-term care facilities.

PubMed

Cookson, B; Mackenzie, D; Kafatos, G; Jans, B; Latour, K; Moro, M L; Ricchizzi, E; Van de Mortel, M; Suetens, C; Fabry, J

2013-09-01

Healthcare-associated infections in long-term care facilities (LTCFs) are of increasing importance. To develop consensus national performance indicators (NPIs) for infection control (ICPI) and antimicrobial stewardship (ASPI) in LTCFs, and assess the performance of 32 European countries against these NPIs. Previously established European standards were the basis for consensus and the same iterative approach with national representatives from the 32 countries. A World Health Organization scoring system recorded how close each country was to implementing each standard. The 42 agreed component indicators were grouped into six NPI categories: 'national programme', 'guidelines', 'expert advice', 'IC structure' (not present in the ASPI), 'surveillance' and 'composite'. 'Guidelines' scored the highest mean total possible score (60%, range 20-100%), followed by 'composite' (53%, range 30-100%), 'expert advice' (48%, range 20-100%), 'surveillance' (47%, range 20-83%), 'national programme' (42%, range 20-100%) and 'IC structure' (39%, range 20-100%). Although several scores were low, some countries were able to implement all NPIs, indicating that this was feasible. Most NPIs were very significantly related, indicating that they were considered to be important by the countries. 'Guidelines' and 'IC structure' were significantly related to European region (P ≤ 0.05). Accreditation/inspection was not evident in seven (22%) countries, nine (28%) countries had accreditation/inspection that included IC assessments, and seven (22%) countries had accreditation/inspection that included IC and antimicrobial stewardship assessments. Multi-variable analysis found that only the NPI and the ICPI 'expert advice' were associated with accreditation/inspection which included IC and antimicrobial stewardship. The identified gaps represent significant potential patient safety issues. The NPIs should serve as a basis for monitoring improvements over the coming years. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Laparoscopic surgery for benign and malign diseases of the digestive system: indications, limitations, and evidence.

PubMed

Küper, Markus Alexander; Eisner, Friederike; Königsrainer, Alfred; Glatzle, Jörg

2014-05-07

The laparoscopic technique was introduced in gastrointestinal surgery in the mid 1980s. Since then, the development of this technique has been extraordinary. Triggered by technical innovations (stapling devices or coagulation/dissecting devices), nowadays any type of gastrointestinal resection has been successfully performed laparoscopically and can be performed laparoscopically dependent on the patient's condition. This summary gives an overview over 30 years of laparoscopic surgery with focus on today's indications and evidence. Main indications remain the more common procedures, e.g., appendectomy, cholecystectomy, bariatric procedures or colorectal resections. For all these indications, the laparoscopic approach has become the gold standard with less perioperative morbidity. Regarding oncological outcome there have been several high-quality randomized controlled trials which demonstrated equivalency between laparoscopic and open colorectal resections. Less common procedures like esophagectomy, oncological gastrectomy, liver and pancreatic resections can be performed successfully as well by an experienced surgeon. However, the evidence for these special indications is poor and a general recommendation cannot be given. In conclusion, laparoscopic surgery has revolutionized the field of gastrointestinal surgery by reducing perioperative morbidity without disregarding surgical principles especially in oncological surgery.

Feedback Signal from Motoneurons Influences a Rhythmic Pattern Generator.

PubMed

Rotstein, Horacio G; Schneider, Elisa; Szczupak, Lidia

2017-09-20

Motoneurons are not mere output units of neuronal circuits that control motor behavior but participate in pattern generation. Research on the circuit that controls the crawling motor behavior in leeches indicated that motoneurons participate as modulators of this rhythmic motor pattern. Crawling results from successive bouts of elongation and contraction of the whole leech body. In the isolated segmental ganglia, dopamine can induce a rhythmic antiphasic activity of the motoneurons that control contraction (DE-3 motoneurons) and elongation (CV motoneurons). The study was performed in isolated ganglia where manipulation of the activity of specific motoneurons was performed in the course of fictive crawling ( crawling ). In this study, the membrane potential of CV was manipulated while crawling was monitored through the rhythmic activity of DE-3. Matching behavioral observations that show that elongation dominates the rhythmic pattern, the electrophysiological activity of CV motoneurons dominates the cycle. Brief excitation of CV motoneurons during crawling episodes resets the rhythmic activity of DE-3, indicating that CV feeds back to the rhythmic pattern generator. CV hyperpolarization accelerated the rhythm to an extent that depended on the magnitude of the cycle period, suggesting that CV exerted a positive feedback on the unit(s) of the pattern generator that controls the elongation phase. A simple computational model was implemented to test the consequences of such feedback. The simulations indicate that the duty cycle of CV depended on the strength of the positive feedback between CV and the pattern generator circuit. SIGNIFICANCE STATEMENT Rhythmic movements of animals are controlled by neuronal networks that have been conceived as hierarchical structures. At the basis of this hierarchy, we find the motoneurons, few neurons at the top control global aspects of the behavior (e.g., onset, duration); and within these two ends, specific neuronal circuits control the actual rhythmic pattern of movements. We have investigated whether motoneurons are limited to function as output units. Analysis of the network that controls crawling behavior in the leech has clearly indicated that motoneurons, in addition to controlling muscle activity, send signals to the pattern generator. Physiological and modeling studies on the role of specific motoneurons suggest that these feedback signals modulate the phase relationship of the rhythmic activity. Copyright © 2017 the authors 0270-6474/17/379149-11$15.00/0.

Neuromuscular assessment in elderly workers with and without work related shoulder/neck trouble: the NEW-study design and physiological findings.

PubMed

Sjøgaard, G; Søgaard, K; Hermens, H J; Sandsjö, L; Läubli, T; Thorn, S; Vollenbroek-Hutten, M M R; Sell, L; Christensen, H; Klipstein, A; Kadefors, R; Merletti, R

2006-01-01

Musculoskeletal disorders in the neck and shoulder area are a major occupational concern in the European countries especially among elderly females. The aim was to assess these disorders based on quantitative EMG indicators and functional tests. 252 female computer users (45-68 years) were recruited from four European countries in two contrast groups: (1) 88 neck/shoulder (NS) cases reporting trouble in the neck and/or shoulder region for more than 30 days during the last year, and (2) 164 NS-controls reporting such trouble for no more than 7 days. Questionnaires, functional/clinical tests, and physiological recordings were performed in workplace related field studies. The results showed no differences in anthropometrics but NS-cases reported more strained head positions and more eye problems than controls. The psychosocial working factors were similar, although, NS-controls had slightly better scores on working conditions, general health, and vitality compared to cases. The NS-cases had lower maximal voluntary contraction (MVC) during shoulder elevation (mean (SD) 310 (122) N) compared to the controls (364 (122) N). During 30% MVC electromyography (EMGrms) in the trapezius muscle was lower in NS-cases (194 (105) muV) than in controls (256 (169) muV), while no differences were found regarding endurance time. Estimated conduction velocity was not different between NS-cases and -controls. Four functional computer tests were performed equally well by NS-cases and -controls, and the corresponding EMG variables also did not differ. A major finding in this large-scale epidemiological study is the significantly lower MVC in NS-cases compared with NS-controls together with lower EMGrms value at 30% MVC, while computer tasks were performed at similar relative muscle activation. The study was unable to reveal quantitative EMG indicators and functional tests that could objectively assess disorders in NS-cases.

Effects of different magnitudes of whole-body vibration on arm muscular performance.

PubMed

Marín, Pedro J; Herrero, Azael J; Sáinz, Nuria; Rhea, Matthew R; García-López, David

2010-09-01

The purpose of this study was to analyze the effects of different vibration magnitudes via feet on the number of repetitions performed, mean velocity, and perceived exertion during a set of elbow-extension exercise to failure (70% 1 repetition maximum [1RM] load). Twenty recreationally active students (14 men and 6 women) performed, in 3 different days, 1 elbow-extension set applying randomly 1 of the 3 experimental conditions: high magnitude (HM; 50 Hz and 2.51 mmp-p; 98.55 mxs-2), low magnitude (LM; 30 Hz and 1.15 mmp-p; 20.44 m.s-2) or control (Control, without vibration stimulus). Results indicate that the vibration via feet provides superimposed stimuli for elbow-extensor performance, enhancing the total number of repetitions performed in the HM and LM conditions, which was significantly higher (p

Measuring, managing and maximizing performance of mineral processing plants

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

Bascur, O.A.; Kennedy, J.P.

1995-12-31

The implementation of continuous quality improvement is the confluence of Total Quality Management, People Empowerment, Performance Indicators and Information Engineering. The supporting information technologies allow a mineral processor to narrow the gap between management business objectives and the process control level. One of the most important contributors is the user friendliness and flexibility of the personal computer in a client/server environment. This synergistic combination when used for real time performance monitoring translates into production cost savings, improved communications and enhanced decision support. Other savings come from reduced time to collect data and perform tedious calculations, act quickly with fresh newmore » data, generate and validate data to be used by others. This paper presents an integrated view of plant management. The selection of the proper tools for continuous quality improvement are described. The process of selecting critical performance monitoring indices for improved plant performance are discussed. The importance of a well balanced technological improvement, personnel empowerment, total quality management and organizational assets are stressed.« less

The impact of pay-for-performance on quality of care for minority patients.

PubMed

Epstein, Arnold M; Jha, Ashish K; Orav, E John

2014-10-01

To determine whether racial disparities in process quality and outcomes of care change under hospital pay-for-performance. Retrospective cohort study comparing the change in racial disparities in process quality and outcomes of care between 2004 and 2008 in hospitals participating in the Premier Hospital Quality Incentive Demonstration versus control hospitals. Using patient-level Hospital Quality Alliance (HQA) data, we identified 226,096 patients in Premier hospitals, which were subject to pay-for-performance (P4P) contracts and 1,607,575 patients at control hospitals who had process of care measured during hospitalization for acute myocardial infarction (AMI), congestive heart failure (CHF), or pneumonia. We additionally identified 123,241 Medicare patients in Premier hospitals and 995,107 in controls who were hospitalized for AMI, CHF, pneumonia, or coronary artery bypass graft (CABG) surgery. We then compared HQA process quality indicators for AMI, CHF, and pneumonia between P4P and control hospitals, as well as risk-adjusted mortality rates for AMI, CHF, pneumonia, and CABG. Black patients initially had lower performance on process quality indicators in both Premier and non-Premier hospitals. The racial gap decreased over time in both groups; the reduction in the gap in Premier hospitals was greater than the gap reduction in non-Premier hospitals for AMI patients. During the study period, mortality generally decreased for blacks relative to whites for AMI, CHF, and pneumonia in both Premier and non-Premier hospitals, with the relative reduction for blacks greatest in Premier hospitals for CHF. Our results show no evidence of a deleterious impact of P4P in the Premier HQID on racial disparities in process quality or outcomes.

Reduced state feedback gain computation. [optimization and control theory for aircraft control

NASA Technical Reports Server (NTRS)

Kaufman, H.

1976-01-01

Because application of conventional optimal linear regulator theory to flight controller design requires the capability of measuring and/or estimating the entire state vector, it is of interest to consider procedures for computing controls which are restricted to be linear feedback functions of a lower dimensional output vector and which take into account the presence of measurement noise and process uncertainty. Therefore, a stochastic linear model that was developed is presented which accounts for aircraft parameter and initial uncertainty, measurement noise, turbulence, pilot command and a restricted number of measurable outputs. Optimization with respect to the corresponding output feedback gains was performed for both finite and infinite time performance indices without gradient computation by using Zangwill's modification of a procedure originally proposed by Powell. Results using a seventh order process show the proposed procedures to be very effective.

Nonlinear stability and control study of highly maneuverable high performance aircraft, phase 2

NASA Technical Reports Server (NTRS)

Mohler, R. R.

1992-01-01

Research leading to the development of new nonlinear methodologies for the adaptive control and stability analysis of high angle of attack aircraft such as the F-18 is discussed. The emphasis has been on nonlinear adaptive control, but associated model development, system identification, stability analysis, and simulation were studied in some detail as well. Studies indicated that nonlinear adaptive control can outperform linear adaptive control for rapid maneuvers with large changes in angle of attack. Included here are studies on nonlinear model algorithmic controller design and an analysis of nonlinear system stability using robust stability analysis for linear systems.

On the feasibility of closed-loop control of intra-aortic balloon pumping

NASA Technical Reports Server (NTRS)

Clark, J. W., Jr.; Bourland, H. M.; Kane, G. R.

1973-01-01

A closed-loop control scheme for the control of intra-aortic balloon pumping has been developed and tested in dog experiments. A performance index reflecting the general objectives of balloon-assist pumping is developed and a modified steepest ascent control algorithm is utilized for the selection of a proper operating point for the balloon during its pumping cycle. This paper attempts to indicate the feasibility of closed-loop control of balloon pumping, and particularly its flexibility in achieving both diastolic augmentation of mean aortic pressure and control of the level of end-diastolic pressure (EDP) an important factor in reducing heart work.

SIMPLE: implementation of recommendations from international evidence-based guidelines on caesarean sections in the Netherlands. Protocol for a controlled before and after study.

PubMed

Melman, Sonja; Schoorel, Ellen N C; Dirksen, Carmen; Kwee, Anneke; Smits, Luc; de Boer, Froukje; Jonkers, Madelaine; Woiski, Mallory D; Mol, Ben Willem J; Doornbos, Johannes P R; Visser, Harry; Huisjes, Anjoke J M; Porath, Martina M; Delemarre, Friso M C; Kuppens, Simone M I; Aardenburg, Robert; Van Dooren, Ivo M A; Vrouenraets, Francis P J M; Lim, Frans T H; Kleiverda, Gunilla; van der Salm, Paulien C M; de Boer, Karin; Sikkema, Marko J; Nijhuis, Jan G; Hermens, Rosella P M G; Scheepers, Hubertina C J

2013-01-03

Caesarean section (CS) rates are rising worldwide. In the Netherlands, the most significant rise is observed in healthy women with a singleton in vertex position between 37 and 42 weeks gestation, whereas it is doubtful whether an improved outcome for the mother or her child was obtained. It can be hypothesized that evidence-based guidelines on CS are not implemented sufficiently. Therefore, the present study has the following objectives: to develop quality indicators on the decision to perform a CS based on key recommendations from national and international guidelines; to use the quality indicators in order to gain insight into actual adherence of Dutch gynaecologists to guideline recommendations on the performance of a CS; to explore barriers and facilitators that have a direct effect on guideline application regarding CS; and to develop, execute, and evaluate a strategy in order to reduce the CS incidence for a similar neonatal outcome (based on the information gathered in the second and third objectives). An independent expert panel of Dutch gynaecologists and midwives will develop a set of quality indicators on the decision to perform a CS. These indicators will be used to measure current care in 20 hospitals with a population of 1,000 women who delivered by CS, and a random selection of 1,000 women who delivered vaginally in the same period. Furthermore, by interviewing healthcare professionals and patients, the barriers and facilitators that may influence the decision to perform a CS will be measured. Based on the results, a tailor-made implementation strategy will be developed and tested in a controlled before-and-after study in 12 hospitals (six intervention, six control hospitals) with regard to effectiveness, experiences, and costs. This study will offer insight into the current CS care and into the hindering and facilitating factors influencing obstetrical policy on CS. Furthermore, it will allow definition of patient categories or situations in which a tailor-made implementation strategy will most likely be meaningful and cost effective, without negatively affecting the outcome for mother and child. http://www.clinicaltrials.gov: NCT01261676.

The effect of blue-enriched white light on cognitive performances and sleepiness of night-shift workers: A field study.

PubMed

Motamedzadeh, Majid; Golmohammadi, Rostam; Kazemi, Reza; Heidarimoghadam, Rashid

2017-08-01

Night-shift works are basically accompanied by reduced cognitive performance, sleepiness, and higher possibility for human error and related incidents. It is therefore crucial to improve individuals' performance and alertness in sensitive places like industries' control room with the ultimate goal of increasing efficiency and reducing the number of possible incidents. Previous research has indicated that blue light is a critical cue for entraining circadian rhythm. As a result, the present study was an attempt to investigate whether blue-enriched white light illumination was a practical strategy to decrease sleepiness and improve cognitive performance during night shifts. The study, which adopted a before-after interventional design, was conducted among 30 control room staff members of petrochemical industry. After baseline assessments under existing lighting conditions, every participant was exposed to two new lighting conditions (namely, 17,000K and 6500K blue-enriched white light), each lasting for a week. Assessments were conducted again at the end of these treatments. In order to measure the subjective sleepiness, Karolinska Sleepiness Scale (KSS) was utilized. Subjects also performed the Conners' Continuous Performance Test II (CPT-II) and 1-back test in order to gauge their cognitive performance, and melatonin assessment was carried out using salivary and Eliza technique. The data was analyzed using two-way repeated measure ANOVA. The results indicated that, compared to normal lighting conditions, participants' sleepiness and melatonin rhythm significantly declined when they were exposed to blue-enriched white light. Furthermore, the experimental condition had a significant effect on the reduction of working memory errors. It also decreased omission errors and the reaction time during the sustained attention task. Thus, using blue-enriched white light may be a proper ergonomic strategy for improving performance and alertness, especially during night, in sensitive environments like control rooms. Copyright © 2017 Elsevier Inc. All rights reserved.

Development of a parameter optimization technique for the design of automatic control systems

NASA Technical Reports Server (NTRS)

Whitaker, P. H.

1977-01-01

Parameter optimization techniques for the design of linear automatic control systems that are applicable to both continuous and digital systems are described. The model performance index is used as the optimization criterion because of the physical insight that can be attached to it. The design emphasis is to start with the simplest system configuration that experience indicates would be practical. Design parameters are specified, and a digital computer program is used to select that set of parameter values which minimizes the performance index. The resulting design is examined, and complexity, through the use of more complex information processing or more feedback paths, is added only if performance fails to meet operational specifications. System performance specifications are assumed to be such that the desired step function time response of the system can be inferred.

Effect of Processing Pressure on Isolated Pore Formation during Controlled Directional Solidification in Small Channels

NASA Technical Reports Server (NTRS)

Cox, Matthew C.; Anilkumar, Amrutur V.; Grugel, RIchard N.; Lee, Chun P.

2008-01-01

Directional solidification experiments were performed, using succinonitrile saturated with nitrogen gas, to examine the effects of in-situ processing pressure changes on the formation growth, and evolution of an isolated, cylindrical gaseous pore. A novel solidification facility, capable of processing thin cylindrical samples (I.D. < 1.0 mm), under controlled pressure conditions, was used for the experiments. A new experimental method for growing the isolated pore from a seed bubble is introduced. The experimental results indicate that an in-situ processing pressure change will result in either a transient change in pore diameter or a complete termination of pore growth, indicating that pressure changes can be used as a control parameter to terminate bubble growth. A simple analytical model has been introduced to explain the experimental observations.

JT9D-70/59 Improved High Pressure Turbine Active Clearance Control System. [for specific fuel consumption improvement

NASA Technical Reports Server (NTRS)

Gaffin, W. O.

1979-01-01

The JT9D-70/59 high pressure turbine active clearance control system was modified to provide reduction of blade tip clearance when the system is activated during cruise operation. The modification increased the flow capacity and air impingement effectiveness of the cooling air manifold to augment turbine case shrinkage capability, and increased responsiveness of the airseal clearance to case shrinkage. The simulated altitude engine testing indicated a significant improvement in specific fuel consumption with the modified system. A 1000 cycle engine endurance test showed no unusual wear or performance deterioration effects on the engine or the clearance control system. Rig tests indicated that the air impingement and seal support configurations used in the engine tests are near optimum.

Interior shadings for office indoor visual comfort in humid climate region

NASA Astrophysics Data System (ADS)

Dinapradipta, Asri; Sudarma, Erwin; Defiana, Ima; Erwindi, Collinthia

2018-03-01

As part of the fenestration system, the interior shadings have also a role to control the indoor environment to maintain indoor visual comfort. As the occupants have personal access to control these, their control behavior then, might enhance or even worsen indoor comfort performance. The controlling behavior might not only influence indoor comfort performance but can also indicate the success or failure of interior shading as a control device element. This paper is intended to report control behavior patterns, as represented by the variety of the slats’ openings of two types of interior shading i.e. Venetian and Vertical blinds and to analyze these on the concurrent impacts to indoor office building’s indoor illuminance and luminance distribution. The purpose of this research is to figure out the shading control patterns as well as to examine the effectiveness of these two types of interior shadings to control indoor visual environment. This study is a quantitative research using experimentation on the slats’ opening of two types of shadings at two identical office rooms. The research results suggested that both types of blinds seem unsuitable for gaining proper illumination values at work planes in humid tropics area. However, these shadings demonstrate good performance for luminance distribution except for that of the closed Venetian blinds.

Design and control of a novel two-speed Uninterrupted Mechanical Transmission for electric vehicles

NASA Astrophysics Data System (ADS)

Fang, Shengnan; Song, Jian; Song, Haijun; Tai, Yuzhuo; Li, Fei; Sinh Nguyen, Truong

2016-06-01

Conventional all-electric vehicles (EV) adopt single-speed transmission due to its low cost and simple construction. However, with the adoption of this type of driveline system, development of EV technology leads to the growing performance requirements of drive motor. Introducing a multi-speed or two-speed transmission to EV offers the possibility of efficiency improvement of the whole powertrain. This paper presents an innovative two-speed Uninterrupted Mechanical Transmission (UMT), which consists of an epicyclic gearing system, a centrifugal clutch and a brake band, allowing the seamless shifting between two gears. Besides, driver's intention is recognized by the control system which is based on fuzzy logic controller (FLC), utilizing the signals of vehicle velocity and accelerator pedal position. The novel UMT shows better dynamic and comfort performance in compare with the optimized AMT with the same gear ratios. Comparison between the control strategy with recognition of driver intention and the conventional two-parameter gear shifting strategy is presented. And the simulation and analysis of the middle layer of optimal gearshift control algorithm is detailed. The results indicate that the UMT adopting FLC and optimal control method provides a significant improvement of energy efficiency, dynamic performance and shifting comfort for EV.

Sliding Mode Tracking Control of a Wire-Driven Upper-Limb Rehabilitation Robot with Nonlinear Disturbance Observer.

PubMed

Niu, Jie; Yang, Qianqian; Wang, Xiaoyun; Song, Rong

2017-01-01

Robot-aided rehabilitation has become an important technology to restore and reinforce motor functions of patients with extremity impairment, whereas it can be extremely challenging to achieve satisfactory tracking performance due to uncertainties and disturbances during rehabilitation training. In this paper, a wire-driven rehabilitation robot that can work over a three-dimensional space is designed for upper-limb rehabilitation, and sliding mode control with nonlinear disturbance observer is designed for the robot to deal with the problem of unpredictable disturbances during robot-assisted training. Then, simulation and experiments of trajectory tracking are carried out to evaluate the performance of the system, the position errors, and the output forces of the designed control scheme are compared with those of the traditional sliding mode control (SMC) scheme. The results show that the designed control scheme can effectively reduce the tracking errors and chattering of the output forces as compared with the traditional SMC scheme, which indicates that the nonlinear disturbance observer can reduce the effect of unpredictable disturbances. The designed control scheme for the wire-driven rehabilitation robot has potential to assist patients with stroke in performing repetitive rehabilitation training.

Following your heart or your head: focusing on emotions versus information differentially influences the decisions of younger and older adults.

PubMed

Mikels, Joseph A; Löckenhoff, Corinna E; Maglio, Sam J; Goldstein, Mary K; Garber, Alan; Carstensen, Laura L

2010-03-01

Research on aging has indicated that whereas deliberative cognitive processes decline with age, emotional processes are relatively spared. To examine the implications of these divergent trajectories in the context of health care choices, we investigated whether instructional manipulations emphasizing a focus on feelings or details would have differential effects on decision quality among younger and older adults. We presented 60 younger and 60 older adults with health care choices that required them to hold in mind and consider multiple pieces of information. Instructional manipulations in the emotion-focus condition asked participants to focus on their emotional reactions to the options, report their feelings about the options, and then make a choice. In the information-focus condition, participants were instructed to focus on the specific attributes, report the details about the options, and then make a choice. In a control condition, no directives were given. Manipulation checks indicated that the instructions were successful in eliciting different modes of processing. Decision quality data indicate that younger adults performed better in the information-focus than in the control condition whereas older adults performed better in the emotion-focus and control conditions than in the information-focus condition. Findings support and extend extant theorizing on aging and decision making as well as suggest that interventions to improve decision-making quality should take the age of the decision maker into account.

A theory and model of conflict detection in air traffic control: incorporating environmental constraints.

PubMed

Loft, Shayne; Bolland, Scott; Humphreys, Michael S; Neal, Andrew

2009-06-01

A performance theory for conflict detection in air traffic control is presented that specifies how controllers adapt decisions to compensate for environmental constraints. This theory is then used as a framework for a model that can fit controller intervention decisions. The performance theory proposes that controllers apply safety margins to ensure separation between aircraft. These safety margins are formed through experience and reflect the biasing of decisions to favor safety over accuracy, as well as expectations regarding uncertainty in aircraft trajectory. In 2 experiments, controllers indicated whether they would intervene to ensure separation between pairs of aircraft. The model closely predicted the probability of controller intervention across the geometry of problems and as a function of controller experience. When controller safety margins were manipulated via task instructions, the parameters of the model changed in the predicted direction. The strength of the model over existing and alternative models is that it better captures the uncertainty and decision biases involved in the process of conflict detection. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

Exhaustion Experiences in Junior Athletes: The Importance of Motivation and Self-Control Competencies.

PubMed

Jordalen, Gro; Lemyre, Pierre-Nicolas; Durand-Bush, Natalie

2016-01-01

Quality of motivation, self-control competencies, as well as past performance experience influence sport participation outcomes in developing athletes. Studies have shown that junior athletes high in self-determined motivation are less prone to experience burnout, while self-control competencies help developing athletes to be conscious and deliberate in their self-regulatory efforts toward elite sport performances and avoid negative sport participation outcomes. Combining the self-determination theory framework and psychosocial theories of self-regulation, the aim of this cross-sectional study was to examine how various types of motivation and self-control competencies together are associated with the development of burnout symptoms in junior athletes. High-level Norwegian winter-sport athletes from elite sport academies ( N = 199; female n = 72; 16-20 years of age) consented to participate. Associations between six types of motivational regulation, self-control, and indices of exhaustion were investigated. We hypothesized that athletes' self-control competencies are important to operate successfully, and influenced by different types of motivation, they are expected to help athletes avoid negative sport participation outcomes such as emotional and physical exhaustion. Structural equation modeling analyses were conducted to analyze these relationships, and results revealed some multifaceted associations. When identifying antecedents of sport participation exhaustion and burnout, there is a need to go beyond the unique framework of motivation theories, and explore what cognitive competencies ensure fulfillment of motivation desires. In the current study, differences in junior athletes' quality of motivation influenced self-control competencies when predicting exhaustion. Interestingly, young athletes driven by self-determined (intrinsic, integrated, and identified), and controlled (introjected and amotivation) regulations in association with self-control offered the strongest negative and positive associations with exhaustion, respectively. Findings clearly indicate that motivation and self-control competencies are meaningfully interrelated when assessing burnout propensity in young developing athletes.

Study on Performance of Integration Control by Man and Machine in Stage of Final Approaching for Spaceship Rendezvous and Docking

NASA Astrophysics Data System (ADS)

Zhou, Qianxiang; Liu, Zhongqi

With the development of manned space technology, space rendezvous and docking (RVD) technology will play a more and more important role. The astronauts’ participation in a final close period of man-machine combination control is an important way of RVD technology. Spacecraft RVD control involves control problem of a total of 12 degrees of freedom (location) and attitude which it relative to the inertial space the orbit. Therefore, in order to reduce the astronauts’ operation load and reduce the security requirements to the ground station and achieve an optimal performance of the whole man-machine system, it is need to study how to design the number of control parameters of astronaut or aircraft automatic control system. In this study, with the laboratory conditions on the ground, a method was put forward to develop an experimental system in which the performance evaluation of spaceship RVD integration control by man and machine could be completed. After the RVD precision requirements were determined, 26 male volunteers aged 20-40 took part in the performance evaluation experiments. The RVD integration control success rates and total thruster ignition time were chosen as evaluation indices. Results show that if less than three RVD parameters control tasks were finished by subject and the rest of parameters control task completed by automation, the RVD success rate would be larger than eighty-eight percent and the fuel consumption would be optimized. In addition, there were two subjects who finished the whole six RVD parameters control tasks by enough train. In conclusion, if the astronauts' role should be integrated into the RVD control, it was suitable for them to finish the heading, pitch and roll control in order to assure the man-machine system high performance. If astronauts were needed to finish all parameter control, two points should be taken into consideration, one was enough fuel and another was enough long operation time.

Respiratory sinus arrhythmia responses to cognitive tasks: effects of task factors and RSA indices.

PubMed

Overbeek, Thérèse J M; van Boxtel, Anton; Westerink, Joyce H D M

2014-05-01

Many studies show that respiratory sinus arrhythmia (RSA) decreases while performing cognitive tasks. However, there is uncertainty about the role of contaminating factors such as physical activity and stress-inducing task variables. Different methods to quantify RSA may also contribute to variable results. In 83 healthy subjects, we studied RSA responses to a working memory task requiring varying levels of cognitive control and a perceptual attention task not requiring strong cognitive control. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean interbeat interval and respiration rate, resulting in eight different RSA indices. The two tasks were clearly differentiated by heart rate and facial EMG reference measures. Cognitive control induced inhibition of RSA whereas perceptual attention generally did not. However, the results show several differences between different RSA indices, emphasizing the importance of methodological variables. Age and sex did not influence the results. Copyright © 2014 Elsevier B.V. All rights reserved.

An implementation strategy to improve the guideline adherence of insurance physicians: an experiment in a controlled setting

PubMed Central

2011-01-01

Background The aim of this study was to investigate the efficacy of a newly developed implementation strategy for the insurance medicine guidelines for depression in the Netherlands. We hypothesized that an educational intervention would increase the insurance physicians' (IPs) guideline adherence in a controlled setting. Methods Forty IPs were allocated in a randomised controlled trial (RCT) to an intervention group (IG) (n = 21) and a control group (CG) (n = 19). The IG received tailored training in applying the guidelines for depression, while the CG received an alternative programme. Baseline (T0) and follow-up (T1) measurements were conducted before and after the intervention within a period of two weeks. The intervention consisted of a workshop in which the evidence-based theory of the guidelines was translated for use in practice, with the help of various tools. The IPs had to write a case-report on the basis of video cases, two before and two after the training. Specially trained and blinded test IPs judged the case reports independently on the basis of six performance indicators. Primary outcome measure in the controlled setting of the trial was guideline adherence measured by six performance indicators on a scale of one to seven. Secondary outcome measure was knowledge of the guidelines for depression. Analyses were performed using Linear Mixed Models, and ANCOVA. Results We found significantly higher scores in the IG than in the CG at T1 for both outcomes. The interaction effect (standard error; p-value) of group crossed with time was 0.97 (0.19; p < 0.0005) for guideline adherence in the controlled setting. The group effect at T1 for the knowledge test was 0.86 (0.40; p = 0.038). Conclusions The newly developed implementation strategy for the insurance medicine guidelines for depression improved the guideline adherence of the trained IPs in disability assessments of clients with depression when performed in a controlled setting. Furthermore, the trained IPs showed gains in knowledge of the guidelines for depression. Trial registration Netherlands' Trial Register NTR1863. PMID:22188876

Autopilot regulation for the Linac4 H- ion source

NASA Astrophysics Data System (ADS)

Voulgarakis, G.; Lettry, J.; Mattei, S.; Lefort, B.; Costa, V. J. Correia

2017-08-01

Linac4 is a 160 MeV H- linear accelerator part of the upgrade of the LHC injector chain. Its cesiated surface H- source is designed to provide a beam intensity of 40-50mA. It is operated with periodical Cs-injection at typically 30 days intervals [1] and this implies that the beam parameters will slowly evolve during operation. Autopilot is a control software package extending CERN developed Inspector framework. The aim of Autopilot is to automatize the mandatory optimization and cesiation processes and to derive performance indicators, thus keeping human intervention minimal. Autopilot has been developed by capitalizing on the experience from manually operating the source. It comprises various algorithms running in real-time, which have been devised to: • Optimize the ion source performance by regulation of H2 injection, RF power and frequency. • Describe the performance of the source with performance indicators, which can be easily understood by operators. • Identify failures, try to recover the nominal operation and send warning in case of deviation from nominal operation. • Make the performance indicators remotely available through Web pages.Autopilot is at the same level of hierarchy as an operator, in the CERN infrastructure. This allows the combination of all ion source devices, providing the required flexibility. Autopilot is executed in a dedicated server, ensuring unique and centralized control, yet allowing multiple operators to interact at runtime, always coordinating between them. Autopilot aims at flexibility, adaptability, portability and scalability, and can be extended to other components of CERN's accelerators. In this paper, a detailed description of the Autopilot algorithms is presented, along with first results of operating the Linac4 H- Ion Source with Autopilot.

Performance of a system of reservoirs on futuristic front

NASA Astrophysics Data System (ADS)

Saha, Satabdi; Roy, Debasri; Mazumdar, Asis

2017-10-01

Application of simulation model HEC-5 to analyze the performance of the DVC Reservoir System (a multipurpose system with a network of five reservoirs and one barrage) on the river Damodar in Eastern India in meeting projected future demand as well as controlling flood for synthetically generated future scenario is addressed here with a view to develop an appropriate strategy for its operation. Thomas-Fiering model (based on Markov autoregressive model) has been adopted for generation of synthetic scenario (monthly streamflow series) and subsequently downscaling of modeled monthly streamflow to daily values was carried out. The performance of the system (analysed on seasonal basis) in terms of `Performance Indices' (viz., both quantity based reliability and time based reliability, mean daily deficit, average failure period, resilience and maximum vulnerability indices) for the projected scenario with enhanced demand turned out to be poor compared to that for historical scenario. However, judicious adoption of resource enhancement (marginal reallocation of reservoir storage capacity) and demand management strategy (curtailment of projected high water requirements and trading off between demands) was found to be a viable option for improvement of the performance of the reservoir system appreciably [improvement being (1-51 %), (2-35 %), (16-96 %), (25-50 %), (8-36 %) and (12-30 %) for the indices viz., quantity based reliability, time based reliability, mean daily deficit, average failure period, resilience and maximum vulnerability, respectively] compared to that with normal storage and projected demand. Again, 100 % reliability for flood control for current as well as future synthetically generated scenarios was noted. The results from the study would assist concerned authority in successful operation of reservoirs in the context of growing demand and dwindling resource.

Cognitive features of psychotic states arising in late life (late paraphrenia).

PubMed

Almeida, O P; Howard, R J; Levy, R; David, A S; Morris, R G; Sahakian, B J

1995-07-01

The cognitive performance of 47 elderly psychotic patients with onset of symptoms in late life (late paraphrenia) was compared to that of 33 controls matched for age, sex, ethnic origin, number of years of education, and pre-morbid IQ as measured by the NART. Neuropsychological indices of general cognitive functioning (MMSE, CAMCOG, WAIS-R verbal and performance scores) showed that patients were performing the tasks at a significantly lower level than controls. Patients also showed a trend to have a lower span capacity than controls, particularly at the spatial span subtest. There was no obvious impairment of learning as measured by the digit and spatial recurring span tasks nor of simultaneous matching-to-sample ability. However, patients' performance on a delayed-matching-to-sample procedure was significantly worse than that of controls. In addition, patients performed worse than controls on the Recognition Memory Test for Faces, but not for Words. Finally, the performance of patients on tests assessing executive functioning (Verbal Fluency Test, Computerized Extra and Intra-Dimensional Shift Task, Computerized Spatial Working Memory Task, and Computerized Tower of London Task) was consistently worse than that of controls. These results suggest that psychotic states arising in late life are predominantly associated with a decline on measures of general cognitive ability and executive functioning. The neuropsychological meaning of these findings is discussed in the light of cognitive models of psychotic symptoms, as well as of schizophrenia and dementia research. We concluded that the lack of a clear pattern of impairment among these patients may be the result of their clinical and cognitive diversity.

No effect on performance tests from a neuromuscular warm-up programme in youth female football: a randomised controlled trial.

PubMed

Lindblom, Hanna; Waldén, Markus; Hägglund, Martin

2012-10-01

The objective of the present randomised controlled trial was to study the effect of a neuromuscular warm-up programme on performance tests in youth female football. Four youth female football teams with players aged 12-16 years were randomised into an intervention group and control group. The intervention was a 15-min neuromuscular warm-up programme carried out twice a week during the 11-week study period. Baseline and follow-up measurements of performance were made indoors and included the star excursion balance test, a countermovement jump test, a triple-hop for distance test, a modified Illinois agility test, and 10- and 20-m sprint tests. Fifty-two players (intervention 28; control 24) took part in baseline measurements, and after dropout, 41 players (intervention 23; control 18) were included for analysis. Minor positive changes were seen in the control group compared to the intervention group for a sub-score of the star excursion balance test (P < 0.05) and in the modified Illinois agility test (P < 0.05). No improvement was seen in the intervention group from baseline to follow-up. The study showed that a neuromuscular warm-up programme carried out during 11 weeks did not improve performance in youth female football. This could indicate that the programme does not contain sufficient stimulus to improve performance. A low player attendance at training sessions, and low specificity between exercises in the warm-up programme and the evaluated performance tests may also contribute to the lack of effect. I.

Neural correlates of individual performance differences in resolving perceptual conflict.

PubMed

Labrenz, Franziska; Themann, Maria; Wascher, Edmund; Beste, Christian; Pfleiderer, Bettina

2012-01-01

Attentional mechanisms are a crucial prerequisite to organize behavior. Most situations may be characterized by a 'competition' between salient, but irrelevant stimuli and less salient, relevant stimuli. In such situations top-down and bottom-up mechanisms interact with each other. In the present fMRI study, we examined how interindividual differences in resolving situations of perceptual conflict are reflected in brain networks mediating attentional selection. Doing so, we employed a change detection task in which subjects had to detect luminance changes in the presence and absence of competing distractors. The results show that good performers presented increased activation in the orbitofrontal cortex (BA 11), anterior cingulate (BA 25), inferior parietal lobule (BA 40) and visual areas V2 and V3 but decreased activation in BA 39. This suggests that areas mediating top-down attentional control are stronger activated in this group. Increased activity in visual areas reflects distinct neuronal enhancement relating to selective attentional mechanisms in order to solve the perceptual conflict. Opposed to good performers, brain areas activated by poor performers comprised the left inferior parietal lobule (BA 39) and fronto-parietal and visual regions were continuously deactivated, suggesting that poor performers perceive stronger conflict than good performers. Moreover, the suppression of neural activation in visual areas might indicate a strategy of poor performers to inhibit the processing of the irrelevant non-target feature. These results indicate that high sensitivity in perceptual areas and increased attentional control led to less conflict in stimulus processing and consequently to higher performance in competitive attentional selection.

Improving creativity performance by short-term meditation.

PubMed

Ding, Xiaoqian; Tang, Yi-Yuan; Tang, Rongxiang; Posner, Michael I

2014-03-19

One form of meditation intervention, the integrative body-mind training (IBMT) has been shown to improve attention, reduce stress and change self-reports of mood. In this paper we examine whether short-term IBMT can improve performance related to creativity and determine the role that mood may play in such improvement. Forty Chinese undergraduates were randomly assigned to short-term IBMT group or a relaxation training (RT) control group. Mood and creativity performance were assessed by the Positive and Negative Affect Schedule (PANAS) and Torrance Tests of Creative Thinking (TTCT) questionnaire respectively. As predicted, the results indicated that short-term (30 min per day for 7 days) IBMT improved creativity performance on the divergent thinking task, and yielded better emotional regulation than RT. In addition, cross-lagged analysis indicated that both positive and negative affect may influence creativity in IBMT group (not RT group). Our results suggested that emotion-related creativity-promoting mechanism may be attributed to short-term meditation.

Cost and Performance Report: Solar-Powered Remediation and pH Control

DTIC Science & Technology

2017-04-01

OMB (Office of Management and Budget) Circular A-94. 2016. Guidelines and Discount Rates for Benefit - Cost Analysis of Federal Programs. Rahner D...ER-201033) Solar-Powered Remediation and pH Control April 2017 This document has been cleared for public release; Distribution Statement A...Program (ESTCP). The publication of this report does not indicate endorsement by the Department of Defense, nor should the contents be construed

Nonlinear stability and control study of highly maneuverable high performance aircraft, phase 2

NASA Technical Reports Server (NTRS)

Mohler, R. R.

1992-01-01

This research should lead to the development of new nonlinear methodologies for the adaptive control and stability analysis of high angle-of-attack aircraft such as the F18 (HARV). The emphasis has been on nonlinear adaptive control, but associated model development, system identification, stability analysis and simulation is performed in some detail as well. Various models under investigation for different purposes are summarized in tabular form. Models and simulation for the longitudinal dynamics have been developed for all types except the nonlinear ordinary differential equation model. Briefly, studies completed indicate that nonlinear adaptive control can outperform linear adaptive control for rapid maneuvers with large changes in alpha. The transient responses are compared where the desired alpha varies from 5 degrees to 60 degrees to 30 degrees and back to 5 degrees in all about 16 sec. Here, the horizontal stabilator is the only control used with an assumed first-order linear actuator with a 1/30 sec time constant.

Development of an Active Flow Control Technique for an Airplane High-Lift Configuration

NASA Technical Reports Server (NTRS)

Shmilovich, Arvin; Yadlin, Yoram; Dickey, Eric D.; Hartwich, Peter M.; Khodadoust, Abdi

2017-01-01

This study focuses on Active Flow Control methods used in conjunction with airplane high-lift systems. The project is motivated by the simplified high-lift system, which offers enhanced airplane performance compared to conventional high-lift systems. Computational simulations are used to guide the implementation of preferred flow control methods, which require a fluidic supply. It is first demonstrated that flow control applied to a high-lift configuration that consists of simple hinge flaps is capable of attaining the performance of the conventional high-lift counterpart. A set of flow control techniques has been subsequently considered to identify promising candidates, where the central requirement is that the mass flow for actuation has to be within available resources onboard. The flow control methods are based on constant blowing, fluidic oscillators, and traverse actuation. The simulations indicate that the traverse actuation offers a substantial reduction in required mass flow, and it is especially effective when the frequency of actuation is consistent with the characteristic time scale of the flow.

Early stage second-language learning improves executive control: evidence from ERP.

PubMed

Sullivan, Margot D; Janus, Monika; Moreno, Sylvain; Astheimer, Lori; Bialystok, Ellen

2014-12-01

A growing body of research has reported a bilingual advantage in performance on executive control tasks, but it is not known at what point in emerging bilingualism these advantages first appear. The present study investigated the effect of early stage second-language training on executive control. Monolingual English-speaking students were tested on a go-nogo task, sentence judgment task, and verbal fluency, before and after 6 months of Spanish instruction. The training group (n = 25) consisted of students enrolled in introductory Spanish and the control group (n = 30) consisted of students enrolled in introductory Psychology. After training, the Spanish group showed larger P3 amplitude on the go-nogo task and smaller P600 amplitude on the judgment task, indicating enhanced performance, with no changes for the control group and no differences between groups on behavioral measures. Results are discussed in terms of neural changes underlying executive control after brief second-language learning. Copyright © 2014 Elsevier Inc. All rights reserved.

Executive and attentional functions in chronic pain: Does performance decrease with increasing task load?

PubMed Central

Oosterman, Joukje M; Derksen, Laura C; van Wijck, Albert JM; Kessels, Roy PC; Veldhuijzen, Dieuwke S

2012-01-01

BACKGROUND: Diminished executive function and attentional control has been reported in chronic pain patients. However, the precise pattern of impairment in these aspects of cognition in chronic pain remains unclear. Moreover, a decline in psychomotor speed could potentially influence executive and attentional control performance in pain patients. OBJECTIVE: To examine different aspects of executive and attentional control in chronic pain together with the confounding role of psychomotor slowing. METHODS: Neuropsychological tests of sustained attention, planning ability, inhibition and mental flexibility were administered to 34 participants with chronic pain and 32 control participants. RESULTS: Compared with the controls, participants with chronic pain took longer to complete tests of sustained attention and mental flexibility, but did not perform worse on inhibition or planning tasks. The decreased performance on the mental flexibility task likely reflects a reduction in psychomotor speed. The pattern of performance on the sustained attention task reveals a specific decline in attention, indicated by a disproportionate decline in performance with an increase in task duration and by increased fluctuations in attention during task performance. No additional effect was noted of pain intensity, pain duration, pain catastrophizing, depressive symptoms, reduced sleep because of the pain or opioid use. CONCLUSIONS: Executive and attention functions are not uniformly affected in chronic pain. At least part of the previously reported decline in executive function in this group may reflect psychomotor slowing. Overall, limited evidence was found that executive and attention performance is indeed lower in chronic pain. Therefore, it can be concluded that in chronic pain sustained attention performance is diminished while mental flexibility, planning and inhibition appear to be intact. PMID:22606680

A Randomized Controlled ERP Study on the Effects of Multi-Domain Cognitive Training and Task Difficulty on Task Switching Performance in Older Adults.

PubMed

Küper, Kristina; Gajewski, Patrick D; Frieg, Claudia; Falkenstein, Michael

2017-01-01

Executive functions are subject to a marked age-related decline, but have been shown to benefit from cognitive training interventions. As of yet, it is, however, still relatively unclear which neural mechanism can mediate training-related performance gains. In the present electrophysiological study, we examined the effects of multi-domain cognitive training on performance in an untrained cue-based task switch paradigm featuring Stroop color words: participants either had to indicate the word meaning of Stroop stimuli (word task) or perform the more difficult task of color naming (color task). One-hundred and three older adults (>65 years old) were randomly assigned to a training group receiving a 4-month multi-domain cognitive training, a passive no-contact control group or an active (social) control group receiving a 4-month relaxation training. For all groups, we recorded performance and EEG measures before and after the intervention. For the cognitive training group, but not for the two control groups, we observed an increase in response accuracy at posttest, irrespective of task and trial type. No training-related effects on reaction times were found. Cognitive training was also associated with an overall increase in N2 amplitude and a decrease of P2 latency on single trials. Training-related performance gains were thus likely mediated by an enhancement of response selection and improved access to relevant stimulus-response mappings. Additionally, cognitive training was associated with an amplitude decrease in the time window of the target-locked P3 at fronto-central electrodes. An increase in the switch positivity during advance task preparation emerged after both cognitive and relaxation training. Training-related behavioral and event-related potential (ERP) effects were not modulated by task difficulty. The data suggest that cognitive training increased slow negative potentials during target processing which enhanced the N2 and reduced a subsequent P3-like component on both switch and non-switch trials and irrespective of task difficulty. Our findings further corroborate the effectiveness of multi-domain cognitive training in older adults and indicate that ERPs can be instrumental in uncovering the neural processes underlying training-related performance gains.

Reconfigurable Control with Neural Network Augmentation for a Modified F-15 Aircraft

NASA Technical Reports Server (NTRS)

Burken, John J.

2007-01-01

This paper describes the performance of a simplified dynamic inversion controller with neural network supplementation. This 6 DOF (Degree-of-Freedom) simulation study focuses on the results with and without adaptation of neural networks using a simulation of the NASA modified F-15 which has canards. One area of interest is the performance of a simulated surface failure while attempting to minimize the inertial cross coupling effect of a [B] matrix failure (a control derivative anomaly associated with a jammed or missing control surface). Another area of interest and presented is simulated aerodynamic failures ([A] matrix) such as a canard failure. The controller uses explicit models to produce desired angular rate commands. The dynamic inversion calculates the necessary surface commands to achieve the desired rates. The simplified dynamic inversion uses approximate short period and roll axis dynamics. Initial results indicated that the transient response for a [B] matrix failure using a Neural Network (NN) improved the control behavior when compared to not using a neural network for a given failure, However, further evaluation of the controller was comparable, with objections io the cross coupling effects (after changes were made to the controller). This paper describes the methods employed to reduce the cross coupling effect and maintain adequate tracking errors. The IA] matrix failure results show that control of the aircraft without adaptation is more difficult [leas damped) than with active neural networks, Simulation results show Neural Network augmentation of the controller improves performance in terms of backing error and cross coupling reduction and improved performance with aerodynamic-type failures.

Less-Costly Ion Implantation of Solar Cells

NASA Technical Reports Server (NTRS)

Fitzgerald, D. J.

1984-01-01

Experiments point way toward more relaxed controls over ion-implanation dosage and uniformity in solar-cell fabrication. Data indicate cell performance, measured by output current density at fixed voltage, virtually same whether implant is particular ion species or broad-beam mixture of several species.

Personality Development in Public School Children. Final Report.

ERIC Educational Resources Information Center

Watt, Norman F.

Investigators compared the emotional adjustment, intellectual functioning, scholastic performance, and social behavior of 54 children who became schizophrenic mental patients with that of 143 matched controls. The following conclusions were drawn: indications of potential schizophrenia include behavioral and emotional deviation in childhood, death…

Design and implementation of fuzzy-PD controller based on relation models: A cross-entropy optimization approach

NASA Astrophysics Data System (ADS)

Anisimov, D. N.; Dang, Thai Son; Banerjee, Santo; Mai, The Anh

2017-07-01

In this paper, an intelligent system use fuzzy-PD controller based on relation models is developed for a two-wheeled self-balancing robot. Scaling factors of the fuzzy-PD controller are optimized by a Cross-Entropy optimization method. A linear Quadratic Regulator is designed to bring a comparison with the fuzzy-PD controller by control quality parameters. The controllers are ported and run on STM32F4 Discovery Kit based on the real-time operating system. The experimental results indicate that the proposed fuzzy-PD controller runs exactly on embedded system and has desired performance in term of fast response, good balance and stabilize.

Incremental Adaptive Fuzzy Control for Sensorless Stroke Control of A Halbach-type Linear Oscillatory Motor

NASA Astrophysics Data System (ADS)

Lei, Meizhen; Wang, Liqiang

2018-01-01

The halbach-type linear oscillatory motor (HT-LOM) is multi-variable, highly coupled, nonlinear and uncertain, and difficult to get a satisfied result by conventional PID control. An incremental adaptive fuzzy controller (IAFC) for stroke tracking was presented, which combined the merits of PID control, the fuzzy inference mechanism and the adaptive algorithm. The integral-operation is added to the conventional fuzzy control algorithm. The fuzzy scale factor can be online tuned according to the load force and stroke command. The simulation results indicate that the proposed control scheme can achieve satisfied stroke tracking performance and is robust with respect to parameter variations and external disturbance.

Has compliance with CLIA requirements really improved quality in US clinical laboratories?

PubMed

Ehrmeyer, Sharon S; Laessig, Ronald H

2004-08-02

The Clinical Laboratory Improvement Amendments of 1988 (CLIA'88) mandate universal requirements for all U.S. clinical laboratory-testing sites. The intent of CLIA'88 is to ensure quality testing through a combination of minimum quality practices that incorporate total quality management concepts. These regulations do not contain established, objective indicators or measures to assess quality. However, there is an implicit assumption that compliance with traditionally accepted good laboratory practices--following manufacturers' directions, routinely analysing quality control materials, applying quality assurance principles, employing and assessing competent testing personnel, and participating in external quality assessment or proficiency testing (PT)--will result in improved test quality. The CLIA'88 regulations do include PT performance standards, which intentionally or unintentionally, define intra-laboratory performance. Passing PT has become a prime motivation for improving laboratory performance; it can also be used as an objective indicator to assess whether compliance to CLIA has improved intra-laboratory quality. Data from 1994 through 2002 indicate that the percentage of laboratories passing PT has increased. In addition to PT performance, subjective indicators of improved quality--frequency of inspection deficiencies, the number of government sanctions for non-compliance, and customer satisfaction--were evaluated. The results from these subjective indicators are more difficult to interpret but also seem to show improved quality in US clinical laboratories eleven years post-CLIA'88.

Integration Test of the High Voltage Hall Accelerator System Components

NASA Technical Reports Server (NTRS)

Kamhawi, Hani; Haag, Thomas; Huang, Wensheng; Pinero, Luis; Peterson, Todd; Dankanich, John

2013-01-01

NASA Glenn Research Center is developing a 4 kilowatt-class Hall propulsion system for implementation in NASA science missions. NASA science mission performance analysis was completed using the latest high voltage Hall accelerator (HiVHAc) and Aerojet-Rocketdyne's state-of-the-art BPT-4000 Hall thruster performance curves. Mission analysis results indicated that the HiVHAc thruster out performs the BPT-4000 thruster for all but one of the missions studied. Tests of the HiVHAc system major components were performed. Performance evaluation of the HiVHAc thruster at NASA Glenn's vacuum facility 5 indicated that thruster performance was lower than performance levels attained during tests in vacuum facility 12 due to the lower background pressures attained during vacuum facility 5 tests when compared to vacuum facility 12. Voltage-Current characterization of the HiVHAc thruster in vacuum facility 5 showed that the HiVHAc thruster can operate stably for a wide range of anode flow rates for discharge voltages between 250 and 600 volts. A Colorado Power Electronics enhanced brassboard power processing unit was tested in vacuum for 1,500 hours and the unit demonstrated discharge module efficiency of 96.3% at 3.9 kilowatts and 650 volts. Stand-alone open and closed loop tests of a VACCO TRL 6 xenon flow control module were also performed. An integrated test of the HiVHAc thruster, brassboard power processing unit, and xenon flow control module was performed and confirmed that integrated operation of the HiVHAc system major components. Future plans include continuing the maturation of the HiVHAc system major components and the performance of a single-string integration test.

The 406 MHz ELT/EPIRBs. [Emergency Locator Transmitters/Emergency Position Indicating Radio Beacons (ELT/EPIRB)

NASA Technical Reports Server (NTRS)

Flatow, F. S.; Gal, C.; Hayes, E. J.

1984-01-01

Specifications for the COSPAS/SARSAT beacons are presented and related design considerations are discussed. Critical design aspects having significant impact on cost and performance are highlighted. Among these is the oscillator, whose frequency drift specifications require stabilization by ovens or digital control. Design options are presented and their impact on cost and performance assessed. Beacon designs developed to meet COSPAS/SARSAT specifications are shown.

X-48B Flight Test Progress Overview

NASA Technical Reports Server (NTRS)

Risch, Timoth K.; Cosentino, Gary B.; Regan, Christopher D.; Kisska, Michael; Princen, Norman

2009-01-01

The results of a series of 39 flight tests of the X-48B Low Speed Vehicle (LSV) performed at the NASA Dryden Flight Research Center from July 2007 through December 2008 are reported here. The goal of these tests is to evaluate the aerodynamic and controls and dynamics performance of the subscale LSV aircraft, eventually leading to the development of a control system for a full-scale vehicle. The X-48B LSV is an 8.5%-scale aircraft of a potential, full-scale Blended Wing Body (BWB) type aircraft and is flown remotely from a ground control station using a computerized flight control system located onboard the aircraft. The flight tests were the first two phases of a planned three-phase research program aimed at ascertaining the flying characteristics of this type of aircraft. The two test phases reported here are: 1) envelope expansion, during which the basic flying characteristics of the airplane were examined, and 2) parameter identification, stalls, and engine-out testing, during which further information on the aircraft performance was obtained and the airplane was tested to the limits of controlled flight. The third phase, departure limiter assaults, has yet to be performed. Flight tests in two different wing leading edge configurations (slats extended and slats retracted) as well as three weight and three center of gravity positions were conducted during each phase. Data gathered in the test program included measured airplane performance parameters such as speed, acceleration, and control surface deflections along with qualitative flying evaluations obtained from pilot and crew observations. Flight tests performed to-date indicate the aircraft exhibits good handling qualities and performance, consistent with pre-flight simulations.

Influence of drive and timing mechanisms on breathing pattern and ventilation during mental task performance.

PubMed

Wientjes, C J; Grossman, P; Gaillard, A W

1998-09-01

Assessment of multiple respiratory measures may provide insight into how behavioral demands affect the breathing pattern. This is illustrated by data from a study among 44 subjects, in which tidal volume, respiration rate, minute ventilation and indices of central drive and timing mechanisms were assessed via inductive plethysmography, in addition to end-tidal PCO2. After a baseline, three conditions of a memory comparison task were presented. The first two conditions differed only with regard to the presence or absence of feedback of performance (NFB and FB). In the third 'all-or-nothing' (AON) condition, subjects only received a monetary bonus, if their performance exceeded that of the previous two conditions. Minute ventilation increased from baseline to all task conditions, and from NFB and FB to AON. Respiration rate increased in all task conditions, but there were no differences between task conditions. Tidal volume decreased during NFB, but was equal to baseline during FB and AON. Of the respiratory control indices, inspiratory flow rate covaried much more closely with minute ventilation than duty cycle. The task performance induced a minor degree of hyperventilation. The discussion focusses on how behavioral demands affect respiratory control processes to produce alterations in breathing pattern and ventilation.

Statistical process control: separating signal from noise in emergency department operations.

PubMed

Pimentel, Laura; Barrueto, Fermin

2015-05-01

Statistical process control (SPC) is a visually appealing and statistically rigorous methodology very suitable to the analysis of emergency department (ED) operations. We demonstrate that the control chart is the primary tool of SPC; it is constructed by plotting data measuring the key quality indicators of operational processes in rationally ordered subgroups such as units of time. Control limits are calculated using formulas reflecting the variation in the data points from one another and from the mean. SPC allows managers to determine whether operational processes are controlled and predictable. We review why the moving range chart is most appropriate for use in the complex ED milieu, how to apply SPC to ED operations, and how to determine when performance improvement is needed. SPC is an excellent tool for operational analysis and quality improvement for these reasons: 1) control charts make large data sets intuitively coherent by integrating statistical and visual descriptions; 2) SPC provides analysis of process stability and capability rather than simple comparison with a benchmark; 3) SPC allows distinction between special cause variation (signal), indicating an unstable process requiring action, and common cause variation (noise), reflecting a stable process; and 4) SPC keeps the focus of quality improvement on process rather than individual performance. Because data have no meaning apart from their context, and every process generates information that can be used to improve it, we contend that SPC should be seriously considered for driving quality improvement in emergency medicine. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison of in-flight and ground-based simulator derived flying qualities and pilot performance for approach and landing tasks

NASA Technical Reports Server (NTRS)

Grantham, William D.; Williams, Robert H.

1987-01-01

For the case of an approach-and-landing piloting task emphasizing response to the landing flare, pilot opinion and performance parameters derived from jet transport aircraft six-degree-of-freedom ground-based and in-flight simulators were compared in order to derive data for the flight-controls/flying-qualities engineers. The data thus obtained indicate that ground simulation results tend to be conservative, and that the effect of control sensitivity is more pronounced for ground simulation. The pilot also has a greater tendency to generate pilot-induced oscillation in ground-based simulation than in flight.

Moderate temperature control technology for a lunar base

NASA Technical Reports Server (NTRS)

Swanson, Theodore D.; Sridhar, K. R.; Gottmann, Matthias

1993-01-01

A parametric analysis is performed to compare different heat pump based thermal control systems for a Lunar Base. Rankine cycle and absorption cycle heat pumps are compared and optimized for a 100 kW cooling load. Variables include the use or lack of an interface heat exchanger, and different operating fluids. Optimization of system mass to radiator rejection temperature is performed. The results indicate a relatively small sensitivity of Rankine cycle system mass to these variables, with optimized system masses of about 6000 kg for the 100 kW thermal load. It is quantitaively demonstrated that absorption based systems are not mass competitive with Rankine systems.

Computer games: a double-edged sword?

PubMed

Sun, De-Lin; Ma, Ning; Bao, Min; Chen, Xang-Chuan; Zhang, Da-Ren

2008-10-01

Excessive computer game playing (ECGP) has already become a serious social problem. However, limited data from experimental lab studies are available about the negative consequences of ECGP on players' cognitive characteristics. In the present study, we compared three groups of participants (current ECGP participants, previous ECGP participants, and control participants) on a Multiple Object Tracking (MOT) task. The previous ECGP participants performed significantly better than the control participants, which suggested a facilitation effect of computer games on visuospatial abilities. Moreover, the current ECGP participants performed significantly worse than the previous ECGP participants. This more important finding indicates that ECGP may be related to cognitive deficits. Implications of this study are discussed.

Programming generality into a performance feedback writing intervention: A randomized controlled trial.

PubMed

Hier, Bridget O; Eckert, Tanya L

2016-06-01

Substantial numbers of students in the United States are performing below grade-level expectations in core academic areas, and these deficits are most pronounced in the area of writing. Although performance feedback procedures have been shown to produce promising short-term improvements in elementary-aged students' writing skills, evidence of maintenance and generalization of these intervention effects is limited. The purpose of this study was to examine the immediate, generalized, and sustained effects of incorporating multiple exemplar training into the performance feedback procedures of a writing intervention using a randomized controlled trial (RCT). Results indicated that although the addition of multiple exemplar training did not improve students' writing performance on measures of stimulus and response generalization, it did result in greater maintenance of intervention effects in comparison to students who received performance feedback without generality programming and students who engaged in weekly writing practice alone. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

The Effect of a Six-Month Dancing Program on Motor-Cognitive Dual-Task Performance in Older Adults.

PubMed

Hamacher, Dennis; Hamacher, Daniel; Rehfeld, Kathrin; Hökelmann, Anita; Schega, Lutz

2015-10-01

Dancing is a complex sensorimotor activity involving physical and mental elements which have positive effects on cognitive functions and motor control. The present randomized controlled trial aims to analyze the effects of a dancing program on the performance on a motor-cognitive dual task. Data of 35 older adults, who were assigned to a dancing group or a health-related exercise group, are presented in the study. In pretest and posttest, we assessed cognitive performance and variability of minimum foot clearance, stride time, and stride length while walking. Regarding the cognitive performance and the stride-to-stride variability of minimum foot clearance, interaction effects have been found, indicating that dancing lowers gait variability to a higher extent than conventional health-related exercise. The data show that dancing improves minimum foot clearance variability and cognitive performance in a dual-task situation. Multi-task exercises (like dancing) might be a powerful tool to improve motor-cognitive dual-task performance.

Unannounced versus announced hospital surveys: a nationwide cluster-randomized controlled trial.

PubMed

Ehlers, Lars Holger; Simonsen, Katherina Beltoft; Jensen, Morten Berg; Rasmussen, Gitte Sand; Olesen, Anne Vingaard

2017-06-01

To evaluate the effectiveness of unannounced versus announced surveys in detecting non-compliance with accreditation standards in public hospitals. A nationwide cluster-randomized controlled trial. All public hospitals in Denmark were invited. Twenty-three hospitals (77%) (3 university hospitals, 5 psychiatric hospitals and 15 general hospitals) agreed to participate. Twelve hospitals were randomized to receive unannounced surveys (intervention group) and eleven hospitals to receive announced surveys (control group). We hypothesized that the hospitals receiving the unannounced surveys would reveal a higher degree of non-compliance with accreditation standards than the hospitals receiving announced surveys. Nine surveyors trained and employed by the Danish Institute for Quality and Accreditation in Healthcare (IKAS) were randomized into teams and conducted all surveys. The outcome was the surveyors' assessment of the hospitals' level of compliance with 113 performance indicators-an abbreviated set of the Danish Healthcare Quality Programme (DDKM) version 2, covering organizational standards, patient pathway standards and patient safety standards. Compliance with performance indicators was analyzed using binomial regression analysis with bootstrapped robust standard errors. In all, 16 202 measurements were acceptable for data analysis. The risk of observing non-compliance with performance indicators for the intervention group compared with the control group was statistically insignificant (risk difference (RD) = -0.6 percentage points [-2.51-1.31], P = 0.54). A converged analysis of the six patient safety critical standards, requiring 100% compliance to gain accreditation status revealed no statistically significant difference (RD = -0.78 percentage points [-4.01-2.44], P = 0.99). Unannounced hospital surveys were not more effective than announced surveys in detecting quality problems in Danish hospitals. ClinicalTrials.gov NCT02348567, https://clinicaltrials.gov/ct2/show/NCT02348567?term=NCT02348567. © The Author 2017. Published by Oxford University Press in association with the International Society for Quality in Health Care.

Static Performance of a Fixed-Geometry Exhaust Nozzle Incorporating Porous Cavities for Shock-Boundary Layer Interaction Control

NASA Technical Reports Server (NTRS)

Asbury, Scott C.; Hunter, Craig A.

1999-01-01

An investigation was conducted in the model preparation area of the Langley 16-Foot Transonic Tunnel to determine the internal performance of a fixed-geometry exhaust nozzle incorporating porous cavities for shock-boundary layer interaction control. Testing was conducted at static conditions using a sub-scale nozzle model with one baseline and 27 porous configurations. For the porous configurations, the effects of percent open porosity, hole diameter, and cavity depth were determined. All tests were conducted with no external flow at nozzle pressure ratios from 1.25 to approximately 9.50. Results indicate that baseline nozzle performance was dominated by unstable, shock-induced, boundary-layer separation at over-expanded conditions. Porous configurations were capable of controlling off-design separation in the nozzle by either alleviating separation or encouraging stable separation of the exhaust flow. The ability of the porous nozzle concept to alternately alleviate separation or encourage stable separation of exhaust flow through shock-boundary layer interaction control offers tremendous off-design performance benefits for fixed-geometry nozzle installations. In addition, the ability to encourage separation on one divergent flap while alleviating it on the other makes it possible to generate thrust vectoring using a fixed-geometry nozzle.

The effect of motivation and positive affect on ego depletion: Replenishment versus release mechanism.

PubMed

Zhu, Ze; Li, Jian; Zhang, Bo; Li, Ye; Zhang, Houcan

2017-12-01

In this study, 2 experiments were conducted to investigate whether motivation and positive affect can alleviate ego depletion and to elucidate their possible mechanisms. In Experiment 1, a crossing-out-letter task was adapted to reach an ego depletion state for Chinese participants. Participants were then randomly assigned to the extrinsic motivation group, the positive affect group or the depletion control group. After the experimental treatment, a dumbbell task was used to measure participants' remaining self-regulatory resources. The results showed that participants in the motivation and positive affect groups performed better on the dumbbell task than participants in the depletion control group. Experiment 2 was similar to Experiment 1 except that participants were asked to perform an additional unexpected dumbbell task after a neutral video following the above procedure. The results of Experiment 1 were replicated; however, participants' performance on the additional dumbbell task differed. The positive affect group performed better than the depletion control group, indicating an increase in self-regulatory resources and thus supporting the replenishment effect of positive affect. No significant difference was found between the motivation group and the depletion control group. © 2015 International Union of Psychological Science.

Modeling and Advanced Control for Sustainable Process ...

EPA Pesticide Factsheets

This book chapter introduces a novel process systems engineering framework that integrates process control with sustainability assessment tools for the simultaneous evaluation and optimization of process operations. The implemented control strategy consists of a biologically-inspired, multi-agent-based method. The sustainability and performance assessment of process operating points is carried out using the U.S. E.P.A.’s GREENSCOPE assessment tool that provides scores for the selected economic, material management, environmental and energy indicators. The indicator results supply information on whether the implementation of the controller is moving the process towards a more sustainable operation. The effectiveness of the proposed framework is illustrated through a case study of a continuous bioethanol fermentation process whose dynamics are characterized by steady-state multiplicity and oscillatory behavior. This book chapter contribution demonstrates the application of novel process control strategies for sustainability by increasing material management, energy efficiency, and pollution prevention, as needed for SHC Sustainable Uses of Wastes and Materials Management.

Ascorbic acid and melatonin reduce heat-induced performance inhibition and oxidative stress in Japanese quails.

PubMed

Sahin, N; Onderci, M; Sahin, K; Gursu, M F; Smith, M O

2004-02-01

1. The effects of ascorbic acid (L-ascorbic acid) and melatonin supplementation on performance, carcase characteristics, malondialdehyde (MDA) as lipid peroxidation indicator, ascorbic acid, retinol, tocopherol and mineral status in the Japanese quail (Coturnix coturnix japonica) exposed to high ambient temperature were evaluated. 2. Two hundred and forty Japanese quails (10 d old) were randomly assigned to 8 treatment groups consisting of 10 replicates of three birds each. The birds were kept in a temperature-controlled room at 22 degrees C (Thermoneutral, TN groups) or 34 degrees C (for 8 h/d; 09:00 to 17:00 h; Heat stress, HS groups). Birds in both TN and HS were fed either a basal (control) diet or the basal diet supplemented with 250 mg of L-ascorbic acid/kg of diet (Ascorbic acid group), 40 mg of melatonin/kg of diet (Melatonin group) or both (Ascorbic acid + Melatonin group). 3. Supplementing heat-stressed quails with ascorbic acid and melatonin improved performance compared with the control group. Effects generally were greatest in quails supplemented with both ascorbic acid and melatonin. 4. Although supplementation did not consistently restore the concentrations of serum ascorbic acid, retinol and tocopherol to those of TN groups, these concentrations increased significantly with supplementation. Furthermore, serum and liver MDA and serum cholesterol and glucose concentrations were lower in the supplemented groups than in the heat-stressed controls. 5. Within each environment, excretion of Ca, P, Mg, Zn, Fe and Cr were lowest in the combination group and, in all cases, highest in the HS group. Interactions between diet and temperature were detected for live weight gain, cold carcase weight, MDA, ascorbic acid, tocopherol concentrations and excretion of zinc. 6. The results of the study indicate that ascorbic acid and melatonin supplementation attenuate the decline in performance and antioxidant and mineral status caused by heat stress and such supplementation may offer protection against heat-stress-related depression in performance of Japanese quails.

Anthelmintic resistance impact on tropical beef cattle productivity: effect on weight gain of weaned calves.

PubMed

Borges, Fernando A; Almeida, Gabriel D; Heckler, Rafael P; Lemes, Raul T; Onizuka, Marcel K V; Borges, Dyego G L

2013-03-01

The performance of grazing cattle in tropical areas is deeply influenced by parasitism, and the increasing reports of resistance are a threat to effective nematode control. The present study aimed to evaluate the effect of avermectins on the performance of weaned calves naturally infected by ivermectin-resistant gastrointestinal nematodes. The effect of four commercial endectocides (ivermectin 2.25 % + abamectin 1.25 %, ivermectin 3.15 %, doramectin 3.15 %, and doramectin 1 %) on parasitism and performance of a hundred weaned Nellore calves were evaluated during 112 days. The most effective anthelmintic showed efficacy of 84 % and resulted in an increase (P < 0.05) of live weight gain of 11.85 kg, compared to untreated group, 9.05 and 9.41 kg compared to those treated with more ineffective avermectins which showed efficacy of 0 and 48.2 %, respectively. A significant (P < 0.05) and weak negative correlation (r = -0.22) between the eggs per gram (EPG) and body weight was observed, indicating that even the low mean EPG (175 ± 150) observed at day 0 in the control group, with predominance of Haemonchus sp., was responsible for production losses. These results indicate that control of nematode parasites in beef cattle in the weaning phase may not result in increased productivity when carried out without technical criteria.

Daily functioning profile of children with attention deficit hyperactive disorder: A pilot study using an ecological assessment.

PubMed

Rosenblum, Sara; Frisch, Carmit; Deutsh-Castel, Tsofia; Josman, Naomi

2015-01-01

Children with attention-deficit hyperactivity disorder (ADHD) often present with activities of daily living (ADL) performance deficits. This study aimed to compare the performance characteristics of children with ADHD to those of controls based on the Do-Eat assessment tool, and to establish the tool's validity. Participants were 23 children with ADHD and 24 matched controls, aged 6-9 years. In addition to the Do-Eat, the Children Activity Scale-Parent (ChAS-P) and the Behavioral Rating Inventory of Executive Function (BRIEF) were used to measure sensorimotor abilities and executive function (EF). Significant differences were found in the Do-Eat scores between children with ADHD and controls. Significant moderate correlations were found between the Do-Eat sensorimotor scores, the ChAS-P and the BRIEF scores in the ADHD group. Significant correlations were found between performance on the Do-Eat and the ChAS-P questionnaire scores, verifying the tool's ecological validity. A single discriminant function described primarily by four Do-Eat variables, correctly classified 95.5% of the study participants into their respective study groups, establishing the tool's predictive validity within this population. These preliminary findings indicate that the Do-Eat may serve as a reliable and valid tool that provides insight into the daily functioning characteristics of children with ADHD. However, further research on larger samples is indicated.

The effect of instructions on postural-suprapostural interactions in three working memory tasks.

PubMed

Burcal, Christopher J; Drabik, Evan C; Wikstrom, Erik A

2014-06-01

Examining postural control while simultaneously performing a cognitive, or suprapostural task, has shown a fairly consistent trend of improving postural control in young healthy adults and provides insight into postural control mechanisms used in everyday life. However, the role of attention driven by explicit verbal instructions while dual-tasking is less understood. Therefore, the purpose of this investigation is to determine the effects of explicit verbal instructions on the postural-suprapostural interactions among various domains of working memory. A total of 22 healthy young adults with a heterogeneous history of ankle sprains volunteered to participate (age: 22.2±5.1 years; n=10 history of ankle sprains, n=12 no history). Participants were asked to perform single-limb balance trials while performing three suprapostural tasks: backwards counting, random number generation, and the manikin test. In addition, each suprapostural task was completed under three conditions of instruction: no instructions, focus on the postural control task, focus on the suprapostural task. The results indicate a significant effect of instructions on postural control outcomes, with postural performance improving in the presence of instructions across all three cognitive tasks which each stress different aspects of working memory. Further, postural-suprapostural interactions appear to be related to the direction or focus of an individual's attention as instructions to focus on the suprapostural task resulted in the greatest postural control improvements.Thus, attention driven by explicit verbal instructions influence postural-suprapostural interactions as measured by a temporal-spatial postural control outcome, time-to-boundary, regardless of the suprapostural task performed. Copyright © 2014 Elsevier B.V. All rights reserved.

The effect of elevations in internal temperature on event-related potentials during a simple cognitive task in humans.

PubMed

Shibasaki, Manabu; Namba, Mari; Oshiro, Misaki; Crandall, Craig G; Nakata, Hiroki

2016-07-01

The effect of hyperthermia on cognitive function remains equivocal, perhaps because of methodological discrepancy. Using electroencephalographic event-related potentials (ERPs), we tested the hypothesis that a passive heat stress impairs cognitive processing. Thirteen volunteers performed repeated auditory oddball paradigms under two thermal conditions, normothermic time control and heat stress, on different days. For the heat stress trial, these paradigms were performed at preheat stress (i.e., normothermic) baseline, when esophageal temperature had increased by ∼0.8°C, when esophageal temperature had increased by ∼2.0°C, and during cooling following the heat stress. The reaction time and ERPs were recorded in each session. For the time control trial, subjects performed the auditory oddball paradigms at approximately the same time interval as they did in the heat stress trial. The peak latency and amplitude of an indicator of auditory processing (N100) were not altered regardless of thermal conditions. An indicator of stimulus classification/evaluation time (latency of P300) and the reaction time were shortened during heat stress; moreover an indicator of cognitive processing (the amplitude of P300) was significantly reduced during severe heat stress (8.3 ± 1.3 μV) relative to the baseline (12.2 ± 1.0 μV, P < 0.01). No changes in these indexes occurred during the time control trial. During subsequent whole body cooling, the amplitude of P300 remained reduced, and the reaction time and latency of P300 remained shortened. These results suggest that excessive elevations in internal temperature reduce cognitive processing but promote classification time. Copyright © 2016 the American Physiological Society.

Variations in colonoscopy practice in Europe: a multicentre descriptive study (EPAGE).

PubMed

Harris, Jennifer K; Vader, John-Paul; Wietlisbach, Vincent; Burnand, Bernard; Gonvers, Jean-Jacques; Froehlich, Florian

2007-01-01

The volume of colonoscopies performed is increasing and differences in colonoscopy practice over time and between centres have been reported. Examination of current practice is important for bench-marking quality. The objective of this study was to examine variations in colonoscopy practice in endoscopy centres internationally. This observational study prospectively included consecutive patients referred for colonoscopy from 21 centres in 11 countries. Patient, procedure and centre characteristics were collected through questionnaires. Descriptive statistics were performed and the variation between centres while controlling for case-mix was examined. A total of 6004 patients were included in the study. Most colonoscopies (93%; range between centres 70-100%) were performed for diagnostic purposes. The proportion of main indications for colonoscopy showed wide variations between centres, the two most common indications, surveillance and haematochezia, ranging between 7-24% and 5-38%, respectively. High-quality cleansing occurred in 74% (range 51-94%) of patients, and 30% (range 0-100%) of patients received deep sedation. Three-quarters (range 0-100%) of the patients were monitored during colonoscopy, and one-quarter (range 14-35%) underwent polypectomy. Colonoscopy was complete in 89% (range 69-98%) of patients and the median total duration was 20 min (range of centre medians 15-30 min). The variation between centres was not reduced when case-mix was controlled for. This study documented wide variations in colonoscopy practice between centres. Controlling for case-mix did not remove these variations, indicating that centre and procedure characteristics play a role. Centres generally were within the existing guidelines, although there is still some work to be done to ensure that all centres attain the goal of providing high-quality colonoscopy.