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Sample records for attention improves performance

  1. Methylphenidate significantly improves driving performance of adults with attention-deficit hyperactivity disorder: a randomized crossover trial.

    NARCIS (Netherlands)

    Verster, J.C.; Bekker, E.M.; Roos, M.; Minova, A.; Eijken, E.J.; Kooij, J.J.; Buitelaar, J.K.; Kenemans, J.L.; Verbaten, M.N.; Olivier, B.; Volkerts, E.R.

    2008-01-01

    Although patients with attention-deficit hyperactivity disorder (ADHD) have reported improved driving performance on methylphenidate, limited evidence exists to support an effect of treatment on driving performance and some regions prohibit driving on methylphenidate. A randomized, crossover trial e

  2. Mindfulness Training Improves Attentional Task Performance in Incarcerated Youth: A Group Randomized Controlled Intervention Trial

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    Noelle R Leonard

    2013-11-01

    Full Text Available We investigated the impact of cognitive behavioral therapy and mindfulness training (CBT/MT on attentional task performance in incarcerated adolescents. Attention is a cognitive system necessary for managing cognitive demands and regulating emotions. Yet persistent and intensive demands, such as those experienced during high-stress intervals like incarceration and the events leading to incarceration, may deplete attention resulting in cognitive failures, emotional disturbances, and impulsive behavior. We hypothesized that CBT/MT may mitigate these deleterious effects of high stress and protect against degradation in attention over the high-stress interval of incarceration. Using a group randomized controlled trial design, we randomly assigned dormitories of incarcerated youth, ages 16 to 18, to a CBT/MT intervention (youth n = 147 or an active control intervention (youth n = 117. Both arms received approximately 750 minutes of intervention in a small-group setting over a 3-5 week period. Youth in the CBT/MT arm also logged the amount of out-of-session time spent practicing MT exercises. The Attention Network Test was used to index attentional task performance at baseline and 4 months post-baseline. Overall, task performance degraded over time in all participants. The magnitude of performance degradation was significantly less in the CBT/MT vs. control arm. Further, within the CBT/MT arm, performance degraded over time in those with no outside-of-class practice time, but remained stable over time in those who practiced mindfulness exercises outside of the session meetings. Thus, these findings suggest that sufficient CBT/MT practice may protect against functional attentional impairments associated with high-stress intervals. Keywords: adolescent development, incarcerated adolescents, detained adolescents, stress, attention, mindfulness meditation.

  3. Evaluation of the Effectiveness of Working Memory Improvement Exercises on Increasing the Attention and School Performance in 9-12 Year Old Children with Attention Deficit

    OpenAIRE

    Atefeh Fakharinezhad; Farzaneh Niknezhadi; Yousef Gorji

    2014-01-01

    The Purpose of the present study is evaluation of the effectiveness of working memory improvement exercises on increasing the attention and school performance in 9-12 year old children with attention deficit. This is a quasi-experimental study which is of pretest-posttest type, with follow-up by a control group. The statistical population of this research includes the 9-12 year old students of Esfahan Province schools with 6 symptoms of attention deficit, who were chosen by multistage cluster...

  4. Manipulating attention via mindfulness induction improves P300-based brain-computer interface performance

    Science.gov (United States)

    Lakey, Chad E.; Berry, Daniel R.; Sellers, Eric W.

    2011-04-01

    In this study, we examined the effects of a short mindfulness meditation induction (MMI) on the performance of a P300-based brain-computer interface (BCI) task. We expected that MMI would harness present-moment attentional resources, resulting in two positive consequences for P300-based BCI use. Specifically, we believed that MMI would facilitate increases in task accuracy and promote the production of robust P300 amplitudes. Sixteen-channel electroencephalographic data were recorded from 18 subjects using a row/column speller task paradigm. Nine subjects participated in a 6 min MMI and an additional nine subjects served as a control group. Subjects were presented with a 6 × 6 matrix of alphanumeric characters on a computer monitor. Stimuli were flashed at a stimulus onset asynchrony (SOA) of 125 ms. Calibration data were collected on 21 items without providing feedback. These data were used to derive a stepwise linear discriminate analysis classifier that was applied to an additional 14 items to evaluate accuracy. Offline performance analyses revealed that MMI subjects were significantly more accurate than control subjects. Likewise, MMI subjects produced significantly larger P300 amplitudes than control subjects at Cz and PO7. The discussion focuses on the potential attentional benefits of MMI for P300-based BCI performance.

  5. Stimulation of postsynapse adrenergic α2A receptor improves attention/cognition performance in an animal model of attention deficit hyperactivity disorder.

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    Kawaura, Kazuaki; Karasawa, Jun-ichi; Chaki, Shigeyuki; Hikichi, Hirohiko

    2014-08-15

    A 5-trial inhibitory avoidance test using spontaneously hypertensive rat (SHR) pups has been used as an animal model of attention deficit hyperactivity disorder (ADHD). However, the roles of noradrenergic systems, which are involved in the pathophysiology of ADHD, have not been investigated in this model. In the present study, the effects of adrenergic α2 receptor stimulation, which has been an effective treatment for ADHD, on attention/cognition performance were investigated in this model. Moreover, neuronal mechanisms mediated through adrenergic α2 receptors were investigated. We evaluated the effects of both clonidine, a non-selective adrenergic α2 receptor agonist, and guanfacine, a selective adrenergic α2A receptor agonist, using a 5-trial inhibitory avoidance test with SHR pups. Juvenile SHR exhibited a shorter transfer latency, compared with juvenile Wistar Kyoto (WKY) rats. Both clonidine and guanfacine significantly prolonged the transfer latency of juvenile SHR. The effects of clonidine and guanfacine were significantly blocked by pretreatment with an adrenergic α2A receptor antagonist. In contrast, the effect of clonidine was not attenuated by pretreatment with an adrenergic α2B receptor antagonist, or an adrenergic α2C receptor antagonist, while it was attenuated by a non-selective adrenergic α2 receptor antagonist. Furthermore, the effects of neither clonidine nor guanfacine were blocked by pretreatment with a selective noradrenergic neurotoxin. These results suggest that the stimulation of the adrenergic α2A receptor improves the attention/cognition performance of juvenile SHR in the 5-trial inhibitory avoidance test and that postsynaptic, rather than presynaptic, adrenergic α2A receptor is involved in this effect.

  6. Treatment of allergic rhinitis is associated with improved attention performance in children: the Allergic Rhinitis Cohort Study for Kids (ARCO-Kids.

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    Dong-Kyu Kim

    Full Text Available BACKGROUND: It has been well known that pediatric allergic rhinitis was associated with poor performance at school due to attention deficit. However, there were no cohort studies for the effect of treatment of allergic rhinitis on attention performance in pediatric population. Thus, the aim of this study was to investigate whether attention performance was improved after treatment in children with allergic rhinitis. METHODS: In this ARCO-Kids (Allergic Rhinitis Cohort Study for Kids, consecutive pediatric patients with rhinitis symptoms underwent a skin prick test and computerized comprehensive attention test. According to the skin prick test results, the children were diagnosed as allergic rhinitis or non- allergic rhinitis. All of the patients were regularly followed up and treated with oral medication or intranasal corticosteroid sprays. The comprehensive attention tests consisted of sustained and divided attention tasks. Each of the tasks was assessed by the attention score which was calculated by the number of omission and commission errors. The comprehension attention test was repeated after 1 year. RESULTS: A total of 797 children with allergic rhinitis and 239 children with non-allergic rhinitis were included. Initially, the attention scores of omission and commission errors on divided attention task were significantly lower in children with allergic rhinitis than in children with non-allergic rhinitis. After 1 year of treatment, children with allergic rhinitis showed improvement in attention: commission error of sustained (95.6±17.0 vs 97.0±16.6 and divided attention task (99.1±15.8 vs 91.8±23.5. Meanwhile, there was no significant difference of attention scores in children with non-allergic rhinitis. CONCLUSIONS: Our study showed that management of allergic rhinitis might be associated with improvement of attention.

  7. A racket-sport intervention improves behavioral and cognitive performance in children with attention-deficit/hyperactivity disorder.

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    Pan, Chien-Yu; Chu, Chia-Hua; Tsai, Chia-Liang; Lo, Shen-Yu; Cheng, Yun-Wen; Liu, Yu-Jen

    2016-10-01

    The present study assessed the effects of a 12-week table tennis exercise on motor skills, social behaviors, and executive functions in children with attention deficit hyperactivity disorder (ADHD). In the first 12-week phase, 16 children (group I) received the intervention, whereas 16 children (group II) did not. A second 12-week phase immediately followed with the treatments reversed. Improvements were observed in executive functions in both groups after the intervention. After the first 12-week phase, some motor and behavioral functions improved in group I. After the second 12-week phase, similar improvements were noted for group II, and the intervention effects achieved in the first phase were persisted in group I. The racket-sport intervention is valuable in promoting motor skills, social behaviors, and executive functions and should be included within the standard-of-care treatment for children with ADHD.

  8. Progesterone-associated increase in ERP amplitude correlates with an improvement in performance in a spatial attention paradigm.

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    Brötzner, Christina P; Klimesch, Wolfgang; Kerschbaum, Hubert H

    2015-01-21

    Ovarian sex hormones modulate neuronal circuits not directly involved in reproductive functions. In the present study, we investigated whether endogenous fluctuations of estradiol and progesterone during the menstrual cycle are associated with early cortical processing stages in a cued spatial attention paradigm. EEG was monitored while young women responded to acoustically cued visual stimuli. Women with large mean amplitude of the event-related potential (ERP) (80-120 ms following visual stimuli) responded faster to visual stimuli. In luteal women, mean amplitude of the ERP as well as alpha amplitude, an indicator of attentional modulation, correlated positively with progesterone. Further, cerebral asymmetry in ERP amplitude in the alpha frequency band following target presentation was restricted to luteal women. Critically, early follicular women responded slower to right hemifield compared to left hemifield targets. In late follicular or luteal women, we did not detect a right hemifield disadvantage. Progesterone correlated negatively with RTs in luteal women. Therefore, whereas our behavioral data indicate a functional cerebral asymmetry in early follicular women, EEG recording reveal a physiological cerebral hemisphere asymmetry in the alpha frequency band in luteal women. We assume that a progesterone-associated enhancement in synchronization of synaptic activity in the alpha frequency band in luteal women improves early categorization of visual targets in a cued spatial attention paradigm.

  9. Adolescents with obstructive sleep apnea adhere poorly to positive airway pressure (PAP, but PAP users show improved attention and school performance.

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    Dean W Beebe

    Full Text Available BACKGROUND: Obstructive Sleep Apnea (OSA is associated with medical and neurobehavioral morbidity across the lifespan. Positive airway pressure (PAP treatment has demonstrated efficacy in treating OSA and has been shown to improve daytime functioning in adults, but treatment adherence can be problematic. There are nearly no published studies examining functional outcomes such as academic functioning in adolescents treated with PAP. This study was conducted as an initial step towards determining whether PAP treatment improves daytime functioning among adolescents with OSA. METHODS: Self-reported academic grades, self- and parent-reported academic quality of life, and objectively-measured attention were assessed before and after PAP was clinically initiated in a sample of 13 obese adolescents with OSA, as well as 15 untreated obese Controls without OSA. Based on adherence data, the treated group was divided into PAP Users (n = 6 and Non-Adherent participants (n = 7. RESULTS: Though demographically similar, the three groups significantly differed in how their academic performance and attention scores changed from baseline to follow-up. Non-Adherent participants showed worsening functioning over time, while PAP Users showed stable or improved functioning, similar to controls. CONCLUSION: Although many adolescents prescribed PAP for OSA are non-adherent to the treatment, those who adhere to treatment can display improved attention and academic functioning.

  10. Mindfulness Meditation Improves Mood, Quality of Life, and Attention in Adults with Attention Deficit Hyperactivity Disorder

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    Bueno, Viviane Freire; Kozasa, Elisa H.; da Silva, Maria Aparecida; Alves, Tânia Maria; Louzã, Mario Rodrigues; Pompéia, Sabine

    2015-01-01

    Objective. Adults with attention deficit hyperactivity disorder (ADHD) display affective problems and impaired attention. Mood in ADHD can be improved by mindful awareness practices (MAP), but results are mixed regarding the enhancement of attentional performance. Here we evaluated MAP-induced changes in quality of life (QoL), mood, and attention in adult ADHD patients and controls using more measures of attention than prior studies. Methods. Twenty-one ADHD patients and 8 healthy controls underwent 8 weekly MAP sessions; 22 similar patients and 9 controls did not undergo the intervention. Mood and QoL were assessed using validated questionnaires, and attention was evaluated using the Attentional Network Test (ANT) and the Conners Continuous Performance Test (CPT II), before and after intervention. Results. MAP enhanced sustained attention (ANT) and detectability (CPT II) and improved mood and QoL of patients and controls. Conclusion. MAP is a complementary intervention that improves affect and attention of adults with ADHD and controls. PMID:26137496

  11. Mindfulness Meditation Improves Mood, Quality of Life, and Attention in Adults with Attention Deficit Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Viviane Freire Bueno

    2015-01-01

    Full Text Available Objective. Adults with attention deficit hyperactivity disorder (ADHD display affective problems and impaired attention. Mood in ADHD can be improved by mindful awareness practices (MAP, but results are mixed regarding the enhancement of attentional performance. Here we evaluated MAP-induced changes in quality of life (QoL, mood, and attention in adult ADHD patients and controls using more measures of attention than prior studies. Methods. Twenty-one ADHD patients and 8 healthy controls underwent 8 weekly MAP sessions; 22 similar patients and 9 controls did not undergo the intervention. Mood and QoL were assessed using validated questionnaires, and attention was evaluated using the Attentional Network Test (ANT and the Conners Continuous Performance Test (CPT II, before and after intervention. Results. MAP enhanced sustained attention (ANT and detectability (CPT II and improved mood and QoL of patients and controls. Conclusion. MAP is a complementary intervention that improves affect and attention of adults with ADHD and controls.

  12. Anxiety and cognitive performance: attentional control theory.

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    Eysenck, Michael W; Derakshan, Nazanin; Santos, Rita; Calvo, Manuel G

    2007-05-01

    Attentional control theory is an approach to anxiety and cognition representing a major development of Eysenck and Calvo's (1992) processing efficiency theory. It is assumed that anxiety impairs efficient functioning of the goal-directed attentional system and increases the extent to which processing is influenced by the stimulus-driven attentional system. In addition to decreasing attentional control, anxiety increases attention to threat-related stimuli. Adverse effects of anxiety on processing efficiency depend on two central executive functions involving attentional control: inhibition and shifting. However, anxiety may not impair performance effectiveness (quality of performance) when it leads to the use of compensatory strategies (e.g., enhanced effort; increased use of processing resources). Directions for future research are discussed.

  13. Improved control of exogenous attention in action video game players

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    Matthew S Cain

    2014-02-01

    Full Text Available Action video game players have demonstrated a number of attentional advantages over non-players. Here, we propose that many of those benefits might be underpinned by improved control over exogenous (i.e., stimulus-driven attention. To test this we used an anti-cuing task, in which a sudden-onset cue indicated that the target would likely appear in a separate location on the opposite side of the fixation point. When the time between the cue onset and the target onset was short (40 ms, non-players (nVGPs showed a typical exogenous attention effect. Their response times were faster to targets presented at the cued (but less probable location compared with the opposite (more probable location. Video game players (VGPs, however, were less likely to have their attention drawn to the location of the cue. When the onset asynchrony was long (600 ms, VGPs and nVGPs were equally able to endogenously shift their attention to the likely (opposite target location. In order to rule out processing-speed differences as an explanation for this result, we also tested VGPs and nVGPs on an attentional blink task. In a version of the attentional blink task that minimized demands on task switching and iconic memory, VGPs and nVGPs did not differ in second target identification performance (i.e., VGPs had the same magnitude of attentional blink as nVGPs, suggesting that the anti-cuing results were due to flexible control over exogenous attention rather than to more general speed-of-processing differences.

  14. Attentional performance, age and scholastic achievement in healthy children.

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    Mireille Trautmann

    Full Text Available BACKGROUND: Attentional processes in children play a critical role in daily school demands and accomplishments. Studies on the association of attentional processes with school achievement and age in healthy school children are scarce. The aim of the present study was to identify correlations between dimensions of attentional performance, scholastic achievement and age. METHODOLOGY/PRINCIPAL FINDINGS: An extensive testing battery was used to assess a wide range of attentional dimensions. A principal component analysis revealed three factors that are related to attentional performance (distractibility, lapses of attention, cognitive speed. Age was negatively associated with distractibility, lapses of attention and cognitive speed, indicating that distractibility and lapses of attention decreased with age in healthy children and resulted in lower cognitive speed. CONCLUSIONS/SIGNIFICANCE: Attentional processes in healthy children should be measured in relation to distractibility, lapses of attention and cognitive speed.

  15. ELECTROENCEPHALOGRAPHIC BIOFEEDBACK IMPROVES FOCUSED ATTENTION IN ATTENTION DEFICIT/HYPERACTIVITY DISORDER

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    E. M. Sokhadze

    2013-01-01

    Full Text Available EEG biofeedback (so called neurofeedback is considered as an efficacious treatment for ADHD. We propose that operant conditioning of EEG in neurofeedback training mode, aimed to mitigate inattention and low arousal in ADHD, will be accompanied by changes in EEG bands' relative power. Patients were 18 children diagnosed with ADHD. The neurofeedback protocol (“Focus/Alertness” by Peak Achievement Trainer, Neurotek, KY used to train patients has focused attention training procedure, which according to specifications, represents wide band EEG amplitude suppression training. Quantitative EEG analysis was completed on each of 25 min long twelve sessions to determine the relative power of each of the EEG bands of interest throughout each session, and from the first session to the last session. Additional statistical analysis was performed to determine significant changes in relative power within sessions (from minute 1 to minute 25, and between sessions (from session 1 to session 12 for an individual patient. We performed analysis of relative power of Theta, Alpha, Low and High Beta, Theta/Alpha, Theta/Beta, and Theta/Low Beta and Theta/High Beta ratios. We performed also analysis between the “Focus”measure and changes in relative power of above EEG rhythms and their ratios. Additional secondary measures of patients’ post-neurofeedback outcomes were assessed using an audio-visual selective attention test (IVA + Plus and behavioral evaluation scores from Aberrant Behavior Checklist. We found that, as expected, Theta/Low Beta and Theta/Alpha ratios decreased significantly from Session 1 to Session 12 and from minute 1 to minute 25 within sessions. The ‘Focus” measure of protocol showed high negative correlation with both Theta/Alpha and Theta/Beta ratios. The findings regarding EEG changes resulting from self-regulation training along with behavioral evaluations will help in elucidation of neural mechanisms of neurofeedback aimed to improve

  16. Children's cognitive performance and selective attention following recent community violence.

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    McCoy, Dana Charles; Raver, C Cybele; Sharkey, Patrick

    2015-03-01

    Research has shown robust relationships between community violence and psychopathology, yet relatively little is known about the ways in which community violence may affect cognitive performance and attention. The present study estimates the effects of police-reported community violence on 359 urban children's performance on a computerized neuropsychological task using a quasi-experimental fixed-effects design. Living in close proximity to a recent violent crime predicted faster but marginally less accurate task performance for the full sample, evolutionarily adaptive patterns of "vigilant" attention (i.e., less attention toward positive stimuli, more attention toward negative stimuli) for children reporting low trait anxiety, and potentially maladaptive patterns of "avoidant" attention for highly anxious children. These results suggest that community violence can directly affect children's cognitive performance while also having different (and potentially orthogonal) impacts on attention deployment depending on children's levels of biobehavioral risk. Implications for mental health and sociological research are discussed.

  17. Individual differences in attentional modulation of cortical responses correlate with selective attention performance.

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    Choi, Inyong; Wang, Le; Bharadwaj, Hari; Shinn-Cunningham, Barbara

    2014-08-01

    Many studies have shown that attention modulates the cortical representation of an auditory scene, emphasizing an attended source while suppressing competing sources. Yet, individual differences in the strength of this attentional modulation and their relationship with selective attention ability are poorly understood. Here, we ask whether differences in how strongly attention modulates cortical responses reflect differences in normal-hearing listeners' selective auditory attention ability. We asked listeners to attend to one of three competing melodies and identify its pitch contour while we measured cortical electroencephalographic responses. The three melodies were either from widely separated pitch ranges ("easy trials"), or from a narrow, overlapping pitch range ("hard trials"). The melodies started at slightly different times; listeners attended either the leading or lagging melody. Because of the timing of the onsets, the leading melody drew attention exogenously. In contrast, attending the lagging melody required listeners to direct top-down attention volitionally. We quantified how attention amplified auditory N1 response to the attended melody and found large individual differences in the N1 amplification, even though only correctly answered trials were used to quantify the ERP gain. Importantly, listeners with the strongest amplification of N1 response to the lagging melody in the easy trials were the best performers across other types of trials. Our results raise the possibility that individual differences in the strength of top-down gain control reflect inherent differences in the ability to control top-down attention.

  18. An Improved Attention Parameter Setting Algorithm Based on Award Learning Mechanism

    Institute of Scientific and Technical Information of China (English)

    Fang Xiuduan; Liu Binhan; Wang Weizhi

    2002-01-01

    The setting of attention parameters plays a role in the performance of synergetic neural network based on PFAP model. This paper first analyzes the attention parameter setting algorithm based on award-penalty learning mechanism. Then, it presents an improved algorithm to overcome its drawbacks. The experimental results demonstrate that the novel algorithm is better than the original one under the same circumstances.

  19. Effects of a Coactor's Focus of Attention on Task Performance

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    Bockler, Anne; Knoblich, Gunther; Sebanz, Natalie

    2012-01-01

    Coactors take into account certain aspects of each other's tasks even when this is not required to perform their own task. The present experiments investigated whether the way a coactor allocates attention affects one's own attentional relation to stimuli that are attended jointly (Experiment 1), individually (Experiment 2), or in parallel…

  20. The Neurocognitive Performance of Visuospatial Attention in Children with Obesity.

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    Tsai, Chia-Liang; Chen, Fu-Chen; Pan, Chien-Yu; Tseng, Yu-Ting

    2016-01-01

    The present study investigates the behavioral performance and event-related potentials (ERPs) in children with obesity and healthy weight children when performing a visuospatial attention task. Twenty-six children with obesity (obese group) and 26 healthy weight children (control group) were recruited. Their behavioral performance during a variant of the Posner paradigm was measured, and brain ERPs were recorded concurrently. The behavioral data revealed that the obese group responded more slowly, especially in the invalid condition, and exhibited a deficit in attentional inhibition capacity as compared to the control group. In terms of cognitive electrophysiological performance, although the obese group did not show significant differences on P3 latency elicited by the target stimuli when compared to the control group, they exhibited smaller P3 amplitudes when performing the visuospatial attention task. These results broaden previous findings, and indicate that childhood obesity is associated with a reduced ability to modulate the executive function network which supports visuospatial attention.

  1. MCNP Progress & Performance Improvements

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Forrest B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bull, Jeffrey S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rising, Michael Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-04-14

    Twenty-eight slides give information about the work of the US DOE/NNSA Nuclear Criticality Safety Program on MCNP6 under the following headings: MCNP6.1.1 Release, with ENDF/B-VII.1; Verification/Validation; User Support & Training; Performance Improvements; and Work in Progress. Whisper methodology will be incorporated into the code, and run speed should be increased.

  2. Continuous Performance Tasks: Not Just about Sustaining Attention

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    Roebuck, Hettie; Freigang, Claudia; Barry, Johanna G.

    2016-01-01

    Purpose: Continuous performance tasks (CPTs) are used to measure individual differences in sustained attention. Many different stimuli have been used as response targets without consideration of their impact on task performance. Here, we compared CPT performance in typically developing adults and children to assess the role of stimulus processing…

  3. Stress improves selective attention towards emotionally neutral left ear stimuli.

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    Hoskin, Robert; Hunter, M D; Woodruff, P W R

    2014-09-01

    Research concerning the impact of psychological stress on visual selective attention has produced mixed results. The current paper describes two experiments which utilise a novel auditory oddball paradigm to test the impact of psychological stress on auditory selective attention. Participants had to report the location of emotionally-neutral auditory stimuli, while ignoring task-irrelevant changes in their content. The results of the first experiment, in which speech stimuli were presented, suggested that stress improves the ability to selectively attend to left, but not right ear stimuli. When this experiment was repeated using tonal stimuli the same result was evident, but only for female participants. Females were also found to experience greater levels of distraction in general across the two experiments. These findings support the goal-shielding theory which suggests that stress improves selective attention by reducing the attentional resources available to process task-irrelevant information. The study also demonstrates, for the first time, that this goal-shielding effect extends to auditory perception.

  4. Does Focus of Attention Improve Snatch Lift Kinematics?

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    Schutts, Kyle S; Wu, Will; Vidal, Anthony; Hiegel, Jamie; Becker, James

    2016-12-24

    Recent motor control literature has demonstrated that using verbal instructions to direct a performer's attention externally (i.e. toward the movement outcome) enhances motor skill performance. The purpose of this study was to investigate how an athlete's focus of attention impacts kinematic performance of the snatch. Using a counterbalanced within-participant design, 12 competitively trained athletes (8 male, 4 female) performed 2 instructional blocks of 3 snatch repetitions at 80% of their most recent training 1RM. Blocks of internal and external instructions were given to the athlete in a random fashion. Results showed that, when focusing internally, athletes significantly (p instructions significantly increased horizontal barbell velocity, relative to internal instructions (see table 2). Additionally an internal focus resulted in significantly larger Barbell-Cervical-Hip (BCH) angles at maximum height of the barbell (MH) (see table 1) compared to an external focus, indicating that the athletes squatted under the barbell too soon. This information adds to the literature suggesting small changes in coaching instructions can impact performance significantly. It is recommended that coaches use instructions that direct an athlete's attention externally, toward the movement outcome, rather than the action itself.

  5. A methodological note on evaluating performance in a sustained-attention-to-response task.

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    Seli, Paul; Jonker, Tanya R; Solman, Grayden J F; Cheyne, James Allan; Smilek, Daniel

    2013-06-01

    We evaluated the influence of speed-accuracy trade-offs on performance in the sustained attention to response task (SART), a task often used to evaluate the effectiveness of techniques designed to improve sustained attention. In the present study, we experimentally manipulated response delay in a variation of the SART and found that commission errors, which are commonly used as an index of lapses in sustained attention, were a systematic function of manipulated differences in response delay. Delaying responses to roughly 800 ms after stimulus onset reduced commission errors substantially. We suggest the possibility that any technique that affects response speed will indirectly alter error rates independently of improvements in sustained attention. Investigators therefore need to carefully explore, report, and correct for changes in response speed that accompany improvements in performance or, alternatively, to employ tasks that control for response speed.

  6. Exogenous attention and color perception: performance and appearance of saturation and hue.

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    Fuller, Stuart; Carrasco, Marisa

    2006-11-01

    Exogenous covert attention is an automatic, transient form of attention that can be triggered by sudden changes in the periphery. Here we test for the effects of attention on color perception. We used the methodology developed by Carrasco, Ling, and Read [Carrasco, M., Ling, S., & Read, S. (2004). Attention alters appearance. Nature Neuroscience, 7 (3) 308-313] to explore the effects of exogenous attention on appearance of saturation (Experiment 1) and of hue (Experiment 2). We also tested orientation discrimination performance for single stimuli defined by saturation or hue (Experiment 3). The results indicate that attention increases apparent saturation, but does not change apparent hue, notwithstanding the fact that it improves orientation discrimination for both saturation and hue stimuli.

  7. Handwriting performance in children with attention deficit hyperactivity disorder (ADHD).

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    Racine, Marie Brossard; Majnemer, Annette; Shevell, Michael; Snider, Laurie

    2008-04-01

    Attention deficit hyperactivity disorder (ADHD) is the most common neurobehavioral condition of childhood. Consequences are multifaceted and include activity limitations in daily-living skills, academic challenges, diminished socialization skills, and motor difficulties. Poor handwriting performance is an example of an affected life skill that has been anecdotally observed by educators and clinicians for this population and can negatively impact academic performance and self-esteem. To guide health and educational service delivery needs, the authors reviewed the evidence in the literature on handwriting difficulties in children with ADHD. Existing evidence would suggest that children with ADHD have impaired handwriting performance, characterized by illegible written material and/or inappropriate speed of execution compared to children without ADHD. Studies with larger sample sizes using standardized measures of handwriting performance are needed to evaluate the prevalence of the problem and to better understand the nature of handwriting difficulties and their impact in this population.

  8. Improving Performance Appraisals

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    Lahti, Robert E.

    1975-01-01

    A positive and creative results-oriented management appraisal system is needed. This article reviews the benefits and requirements of such a system, lists the common pitfalls of shoddy evaluation attempts, describes the four basic kinds of performance appraisal systems, and offers suggestions for creating a successful system. (DC)

  9. Sustained attention performance during sleep deprivation: evidence of state instability

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    Doran, S. M.; Van Dongen, H. P.; Dinges, D. F.

    2001-01-01

    Nathaniel Kleitman was the first to observe that sleep deprivation in humans did not eliminate the ability to perform neurobehavioral functions, but it did make it difficult to maintain stable performance for more than a few minutes. To investigate variability in performance as a function of sleep deprivation, n = 13 subjects were tested every 2 hours on a 10-minute, sustained-attention, psychomotor vigilance task (PVT) throughout 88 hours of total sleep deprivation (TSD condition), and compared to a control group of n = 15 subjects who were permitted a 2-hour nap every 12 hours (NAP condition) throughout the 88-hour period. PVT reaction time means and standard deviations increased markedly among subjects and within each individual subject in the TSD condition relative to the NAP condition. TSD subjects also had increasingly greater performance variability as a function of time on task after 18 hours of wakefulness. During sleep deprivation, variability in PVT performance reflected a combination of normal timely responses, errors of omission (i.e., lapses), and errors of commission (i.e., responding when no stimulus was present). Errors of omission and errors of commission were highly intercorrelated across deprivation in the TSD condition (r = 0.85, p = 0.0001), suggesting that performance instability is more likely to include compensatory effort than a lack of motivation. The marked increases in PVT performance variability as sleep loss continued supports the "state instability" hypothesis, which posits that performance during sleep deprivation is increasingly variable due to the influence of sleep initiating mechanisms on the endogenous capacity to maintain attention and alertness, thereby creating an unstable state that fluctuates within seconds and that cannot be characterized as either fully awake or asleep.

  10. Regular, brief mindfulness meditation practice improves electrophysiological markers of attentional control

    Directory of Open Access Journals (Sweden)

    Adam W Moore

    2012-02-01

    Full Text Available Mindfulness based meditation practices involve various attentional skills, including the ability to sustain and focus ones attention. During a simple mindful breathing practice, sustained attention is required to maintain focus on the breath while cognitive control is required to detect mind wandering. We thus hypothesized that regular, brief mindfulness training would result in improvements in the self regulation of attention and foster changes in neuronal activity related to attentional control.A longitudinal randomized control group EEG study was conducted. At baseline (T1, 40 meditation naïve participants were randomized into a wait list group and a meditation group, who received three hours mindfulness meditation training. 28 participants remained in the final analysis. At T1, after 8 weeks (T2 and after 16 weeks (T3, all participants performed a computerized Stroop task (a measure of attentional control while the 64-channel EEG was recorded. Between T1 and T3 the meditators were requested to meditate daily for ten minutes.Event-related potential (ERP analysis highlighted two between group effects that developed over the course of the 16-week mindfulness training. An early effect at left and right posterior sites 160 – 240 ms post stimulus indicated that meditation practice improved the focusing of attentional resources. A second effect at central posterior sites 310 – 380 ms post stimulus reflects that meditation practice reduced the recruitment of resources during object recognition processes, especially for incongruent stimuli. Scalp topographies and source analyses (VARETA indicate relevant changes in neural sources, pertaining to left medial and lateral occipitotemporal areas for the early effect and right lateral occipitotemporal and inferior temporal areas for the later effect.The results suggest that mindfulness meditation may alter the efficiency of allocating cognitive resources, leading to improved self regulation of

  11. Regular, brief mindfulness meditation practice improves electrophysiological markers of attentional control.

    Science.gov (United States)

    Moore, Adam; Gruber, Thomas; Derose, Jennifer; Malinowski, Peter

    2012-01-01

    Mindfulness-based meditation practices involve various attentional skills, including the ability to sustain and focus ones attention. During a simple mindful breathing practice, sustained attention is required to maintain focus on the breath while cognitive control is required to detect mind wandering. We thus hypothesized that regular, brief mindfulness training would result in improvements in the self-regulation of attention and foster changes in neuronal activity related to attentional control. A longitudinal randomized control group EEG study was conducted. At baseline (T1), 40 meditation naïve participants were randomized into a wait list group and a meditation group, who received three hours mindfulness meditation training. Twenty-eight participants remained in the final analysis. At T1, after eight weeks (T2) and after 16 weeks (T3), all participants performed a computerized Stroop task (a measure of attentional control) while the 64-channel EEG was recorded. Between T1 and T3 the meditators were requested to meditate daily for 10 min. Event-related potential (ERP) analysis highlighted two between group effects that developed over the course of the 16-week mindfulness training. An early effect at left and right posterior sites 160-240 ms post-stimulus indicated that meditation practice improved the focusing of attentional resources. A second effect at central posterior sites 310-380 ms post-stimulus reflects that meditation practice reduced the recruitment of resources during object recognition processes, especially for incongruent stimuli. Scalp topographies and source analyses (Variable Resolution Electromagnetic Tomography, VARETA) indicate relevant changes in neural sources, pertaining to left medial and lateral occipitotemporal areas for the early effect and right lateral occipitotemporal and inferior temporal areas for the later effect. The results suggest that mindfulness meditation may alter the efficiency of allocating cognitive resources, leading

  12. Action video games and improved attentional control: Disentangling selection- and response-based processes.

    Science.gov (United States)

    Chisholm, Joseph D; Kingstone, Alan

    2015-10-01

    Research has demonstrated that experience with action video games is associated with improvements in a host of cognitive tasks. Evidence from paradigms that assess aspects of attention has suggested that action video game players (AVGPs) possess greater control over the allocation of attentional resources than do non-video-game players (NVGPs). Using a compound search task that teased apart selection- and response-based processes (Duncan, 1985), we required participants to perform an oculomotor capture task in which they made saccades to a uniquely colored target (selection-based process) and then produced a manual directional response based on information within the target (response-based process). We replicated the finding that AVGPs are less susceptible to attentional distraction and, critically, revealed that AVGPs outperform NVGPs on both selection-based and response-based processes. These results not only are consistent with the improved-attentional-control account of AVGP benefits, but they suggest that the benefit of action video game playing extends across the full breadth of attention-mediated stimulus-response processes that impact human performance.

  13. Attentive Turkers: MTurk participants perform better on online attention checks than do subject pool participants.

    Science.gov (United States)

    Hauser, David J; Schwarz, Norbert

    2016-03-01

    Participant attentiveness is a concern for many researchers using Amazon's Mechanical Turk (MTurk). Although studies comparing the attentiveness of participants on MTurk versus traditional subject pool samples have provided mixed support for this concern, attention check questions and other methods of ensuring participant attention have become prolific in MTurk studies. Because MTurk is a population that learns, we hypothesized that MTurkers would be more attentive to instructions than are traditional subject pool samples. In three online studies, participants from MTurk and collegiate populations participated in a task that included a measure of attentiveness to instructions (an instructional manipulation check: IMC). In all studies, MTurkers were more attentive to the instructions than were college students, even on novel IMCs (Studies 2 and 3), and MTurkers showed larger effects in response to a minute text manipulation. These results have implications for the sustainable use of MTurk samples for social science research and for the conclusions drawn from research with MTurk and college subject pool samples.

  14. Performance improvement in multinational corporations

    OpenAIRE

    Liu, Yang

    2015-01-01

    The aim of this thesis work is to develop a performance improvement model template which supports multinational corporations in their daily operations. This has been achieved through literature review and four case studies. With analysis and synthesis, a complete performance improvement model template is carried out based on balanced score card which can be considered as an instruction or reference for improvement work in multinational corporations. After experienced the transformation from i...

  15. Working-memory performance is related to spatial breadth of attention.

    Science.gov (United States)

    Kreitz, Carina; Furley, Philip; Memmert, Daniel; Simons, Daniel J

    2015-11-01

    Working memory and attention are closely related constructs. Models of working memory often incorporate an attention component, and some even equate working memory and attentional control. Although some attention-related processes, including inhibitory control of response conflict and interference resolution, are strongly associated with working memory, for other aspects of attention the link is less clear. We examined the association between working-memory performance and attentional breadth, the ability to spread attention spatially. If the link between attention and working memory is broader than inhibitory and interference resolution processes, then working-memory performance might also be associated with other attentional abilities, including attentional breadth. We tested 123 participants on a variety of working-memory and attentional-breadth measures, finding a strong correlation between performances on these two types of tasks. This finding demonstrates that the link between working memory and attention extends beyond inhibitory processes.

  16. Regular, brief mindfulness meditation practice improves electrophysiological markers of attentional control

    OpenAIRE

    2012-01-01

    Mindfulness-based meditation practices involve various attentional skills, including the ability to sustain and focus ones attention. During a simple mindful breathing practice, sustained attention is required to maintain focus on the breath while cognitive control is required to detect mind wandering. We thus hypothesized that regular, brief mindfulness training would result in improvements in the self-regulation of attention and foster changes in neuronal activity related to attentional con...

  17. Serotonergic neurotransmission and lapses of attention in children and adolescents with attention deficit hyperactivity disorder: availability of tryptophan influences attentional performance.

    Science.gov (United States)

    Zepf, Florian D; Gaber, Tilman J; Baurmann, David; Bubenzer, Sarah; Konrad, Kerstin; Herpertz-Dahlmann, Beate; Stadler, Christina; Poustka, Fritz; Wöckel, Lars

    2010-08-01

    Deficiencies in serotonergic (5-HT) neurotransmission have frequently been linked to altered attention and memory processes. With attention deficit hyperactivity disorder (ADHD) being associated with impaired attention and working memory, this study investigated the effects of a diminished 5-HT turnover achieved by rapid tryptophan depletion (RTD) on attentional performance in children and adolescents with ADHD. Twenty-two male patients with ADHD (aged 9-15 yr) received the RTD procedure Moja-De and a tryptophan (Trp)-balanced placebo (Pla) in a randomized, double-blind, within-subject crossover design on two separate study days. Lapses of attention (LA) and phasic alertness (PA) were assessed within the test battery for attentional performance under depleted and sham-depleted conditions 120 (T1), 220 (T2) and 300 (T3) min after intake of RTD/Pla. At T1 there was a significant main effect for RTD, indicating more LA under intake of a Trp-balanced Pla compared to diminished 5-HT neurotransmission. For T2/T3 there were no such effects. PA was not affected by the factors RTD/Pla and time. Interactions of 5-HT with other neurotransmitters as possible underlying neurochemical processes could be subject to further investigations involving healthy controls as regards altered attentional performance in children and adolescents.

  18. Age effects on gray matter volume and attentional performance in Zen meditation.

    Science.gov (United States)

    Pagnoni, Giuseppe; Cekic, Milos

    2007-10-01

    Zen meditation, a Buddhist practice centered on attentional and postural self-regulation, has been speculated to bring about beneficial long-term effects for the individual, ranging from stress reduction to improvement of cognitive function. In this study, we examined how the regular practice of meditation may affect the normal age-related decline of cerebral gray matter volume and attentional performance observed in healthy individuals. Voxel-based morphometry for MRI anatomical brain images and a computerized sustained attention task were employed in 13 regular practitioners of Zen meditation and 13 matched controls. While control subjects displayed the expected negative correlation of both gray matter volume and attentional performance with age, meditators did not show a significant correlation of either measure with age. The effect of meditation on gray matter volume was most prominent in the putamen, a structure strongly implicated in attentional processing. These findings suggest that the regular practice of meditation may have neuroprotective effects and reduce the cognitive decline associated with normal aging.

  19. Attention in Williams Syndrome and Down's Syndrome: Performance on the New Early Childhood Attention Battery

    Science.gov (United States)

    Breckenridge, Kate; Braddick, Oliver; Anker, Shirley; Woodhouse, Margaret; Atkinson, Janette

    2013-01-01

    Attentional problems are commonly reported as a feature of the behavioural profile in both Williams syndrome (WS) and Down's syndrome (DS). Recent studies have begun to investigate these impairments empirically, acknowledging the need for an approach that considers cross-syndrome comparisons and developmental changes across the different component…

  20. Contributions of sensory coding and attentional control to individual differences in performance in spatial auditory selective attention tasks

    Directory of Open Access Journals (Sweden)

    Lengshi Dai

    2016-10-01

    Full Text Available Listeners with normal hearing thresholds differ in their ability to steer attention to whatever sound source is important. This ability depends on top-down executive control, which modulates the sensory representation of sound in cortex. Yet, this sensory representation also depends on the coding fidelity of the peripheral auditory system. Both of these factors may thus contribute to the individual differences in performance. We designed a selective auditory attention paradigm in which we could simultaneously measure envelope following responses (EFRs, reflecting peripheral coding, onset event-related potentials from the scalp (ERPs, reflecting cortical responses to sound, and behavioral scores. We performed two experiments that varied stimulus conditions to alter the degree to which performance might be limited due to fine stimulus details vs. due to control of attentional focus. Consistent with past work, in both experiments we find that attention strongly modulates cortical ERPs. Importantly, in Experiment I, where coding fidelity limits the task, individual behavioral performance correlates with subcortical coding strength (derived by computing how the EFR is degraded for fully masked tones compared to partially masked tones; however, in this experiment, the effects of attention on cortical ERPs were unrelated to individual subject performance. In contrast, in Experiment II, where sensory cues for segregation are robust (and thus less of a limiting factor on task performance, inter-subject behavioral differences correlate with subcortical coding strength. In addition, after factoring out the influence of subcortical coding strength, behavioral differences are also correlated with the strength of attentional modulation of ERPs. These results support the hypothesis that behavioral abilities amongst listeners with normal hearing thresholds can arise due to both subcortical coding differences and differences in attentional control, depending on

  1. Windows with improved energy performances

    DEFF Research Database (Denmark)

    Laustsen, Jacob Birck; Svendsen, Svend

    2003-01-01

    Heat loss through windows represents a considerable part of the total heat loss from houses. However, apart from providing daylight access and view, windows offer a unique potential for solar gain to be exploited during the heating season. Until now valuation of the energy performance of windows...... with respect to the overall energy performance of windows. By selecting some of the best solutions a new low energy window has been developed for high latitude climates and a prototype manufactured. Simple and realistic improvements such as reducing the frame width and using glass with low iron content have...... be improved considerably in a fairly simple way without increasing the cost....

  2. Pay attention to impulsivity: modelling low attentive and high impulsive subtypes of adult ADHD in the 5-choice continuous performance task (5C-CPT) in female rats.

    Science.gov (United States)

    Tomlinson, Anneka; Grayson, Ben; Marsh, Samuel; Harte, Michael K; Barnes, Samuel A; Marshall, Kay M; Neill, Joanna C

    2014-08-01

    Varying levels of attention and impulsivity deficits are core features of the three subtypes of adult attention deficit-hyperactivity disorder (ADHD). To date, little is known about the neurobiological correlates of these subtypes. Development of a translational animal model is essential to improve our understanding and improve therapeutic strategies. The 5-choice continuous performance task (5C-CPT) in rats can be used to examine different forms of attention and impulsivity. Adult rats were trained to pre-set 5C-CPT criterion and subsequently separated into subgroups according to baseline levels of sustained attention, vigilance, premature responding and response disinhibition in the 5C-CPT. The behavioural subgroups were selected to represent the different subtypes of adult ADHD. Consequently, effects of the clinically used pharmacotherapies (methylphenidate and atomoxetine) were assessed in the different subgroups. Four subgroups were identified: low-attentive (LA), high-attentive (HA), high-impulsive (HI) and low-impulsive (LI). Methylphenidate and atomoxetine produced differential effects in the subgroups. Methylphenidate increased sustained attention and vigilance in LA animals, and reduced premature responding in HI animals. Atomoxetine also improved sustained attention and vigilance in LA animals, and reduced response disinhibition and premature responding in HI animals. This is the first study using adult rats to demonstrate the translational value of the 5C-CPT to select subgroups of rats, which may be used to model the subtypes observed in adult ADHD. Our findings suggest that this as an important paradigm to increase our understanding of the neurobiological underpinnings of adult ADHD-subtypes and their response to pharmacotherapy.

  3. Attentional Control Buffers the Effect of Public Speaking Anxiety on Performance

    OpenAIRE

    Jones, Christopher R.; Fazio, Russell H.; Vasey, Michael W.

    2011-01-01

    We explored dispositional differences in the ability to self-regulate attentional processes in the domain of public speaking. Participants first completed measures of speech anxiety and attentional control. In a second session, participants prepared and performed a short speech. Fear of public speaking negatively impacted performance only for those low in attentional control. Thus, attentional control appears to act as a buffer that facilitates successful self-regulation despite performance a...

  4. Attentional Control Buffers the Effect of Public Speaking Anxiety on Performance.

    Science.gov (United States)

    Jones, Christopher R; Fazio, Russell H; Vasey, Michael W

    2012-09-01

    We explored dispositional differences in the ability to self-regulate attentional processes in the domain of public speaking. Participants first completed measures of speech anxiety and attentional control. In a second session, participants prepared and performed a short speech. Fear of public speaking negatively impacted performance only for those low in attentional control. Thus, attentional control appears to act as a buffer that facilitates successful self-regulation despite performance anxiety.

  5. EEG beta band activity is related to attention and attentional deficits in the visual performance of elderly subjects.

    Science.gov (United States)

    Gola, Mateusz; Magnuski, Mikołaj; Szumska, Izabela; Wróbel, Andrzej

    2013-09-01

    We have previously shown that beta-band EEG activity is related to attentional modulation in the visual system of cats and humans. In a separate experiment we also observed that some elderly subjects expressed beta-band power decreases during a simple visual attention task, an effect which was accompanied by low behavioral accuracy in this subgroup. Here, we conducted a detailed examination of beta power deficits in elderly subjects in comparison to young controls. In order to do so, we equalized the subjective level of task difficulty by adjusting visual stimuli presentation duration in such a way that elderly and young subjects achieved similar behavioral results. We found that: (1) beta-band power of EEG signals recorded over occipital regions in elderly and young groups is related to visual attention, as judged from increases in beta power preceding correct responses and lack of beta activity change before erroneous responses; (2) despite forming a homogeneous group when screened for dementia (MMSE), age, education level, visual correction, and speed-accuracy trade-off strategy, elderly subjects could be assigned into one of the two subgroups: high performers, who did not differ from young performers in terms of beta-band power increases, and low performers, whose beta power decreased during the most difficult attentional conditions (shortest - 3s and longest - 11s cue-target delays). These findings posit that the beta-band activity decrease recorded in low performing elderly subjects reflects difficulty in activation and deficits in sustaining attentional processes.

  6. Divided attention improves delayed, but not immediate retrieval of a consolidated memory.

    Directory of Open Access Journals (Sweden)

    Yoav Kessler

    Full Text Available A well-documented dissociation between memory encoding and retrieval concerns the role of attention in the two processes. The typical finding is that divided attention (DA during encoding impairs future memory, but retrieval is relatively robust to attentional manipulations. However, memory research in the past 20 years had demonstrated that retrieval is a memory-changing process, in which the strength and availability of information are modified by various characteristics of the retrieval process. Based on this logic, several studies examined the effects of DA during retrieval (Test 1 on a future memory test (Test 2. These studies yielded inconsistent results. The present study examined the role of memory consolidation in accounting for the after-effect of DA during retrieval. Initial learning required a classification of visual stimuli, and hence involved incidental learning. Test 1 was administered 24 hours after initial learning, and therefore required retrieval of consolidated information. Test 2 was administered either immediately following Test 1 or after a 24-hour delay. Our results show that the effect of DA on Test 2 depended on this delay. DA during Test 1 did not affect performance on Test 2 when it was administered immediately, but improved performance when Test 2 was given 24-hours later. The results are consistent with other findings showing long-term benefits of retrieval difficulty. Implications for theories of reconsolidation in human episodic memory are discussed.

  7. Divided attention improves delayed, but not immediate retrieval of a consolidated memory.

    Science.gov (United States)

    Kessler, Yoav; Vandermorris, Susan; Gopie, Nigel; Daros, Alexander; Winocur, Gordon; Moscovitch, Morris

    2014-01-01

    A well-documented dissociation between memory encoding and retrieval concerns the role of attention in the two processes. The typical finding is that divided attention (DA) during encoding impairs future memory, but retrieval is relatively robust to attentional manipulations. However, memory research in the past 20 years had demonstrated that retrieval is a memory-changing process, in which the strength and availability of information are modified by various characteristics of the retrieval process. Based on this logic, several studies examined the effects of DA during retrieval (Test 1) on a future memory test (Test 2). These studies yielded inconsistent results. The present study examined the role of memory consolidation in accounting for the after-effect of DA during retrieval. Initial learning required a classification of visual stimuli, and hence involved incidental learning. Test 1 was administered 24 hours after initial learning, and therefore required retrieval of consolidated information. Test 2 was administered either immediately following Test 1 or after a 24-hour delay. Our results show that the effect of DA on Test 2 depended on this delay. DA during Test 1 did not affect performance on Test 2 when it was administered immediately, but improved performance when Test 2 was given 24-hours later. The results are consistent with other findings showing long-term benefits of retrieval difficulty. Implications for theories of reconsolidation in human episodic memory are discussed.

  8. Rapid improvement in academic grades following methylphenidate treatment in attention-deficit hyperactivity disorder.

    Science.gov (United States)

    Yang, Pinchen; Chung, Li-Chen; Chen, Cheng-Sheng; Chen, Cheng-Chung

    2004-02-01

    In the present study a 16 week comparison study was conducted of behavioral, cognitive and educational measures in school-age Taiwanese children with attention-deficit hyperactivity disorder (ADHD) receiving open-label methylphenidate (MPH). Subjects include 14 male and five female ADHD children. They received MPH twice per day continuously for 16 weeks. Measures of behavior, cognitive function (Wisconsin Card Sorting Test, Tower of London and Continuous Performance Test), Chinese and arithmetic learning achievement were compared with those of their baseline condition. After MPH, 68-78% of children showed improving behavior in classroom and at home. Among the neuropsychological tests, only the percentage of preservative error was improved (P = 0.022). Approximately 61-66% of children had improvement in academic learning (P = 0.013 for Chinese, 0.004 for arithmetic). The MPH treatment demonstrated improvement in domains of classroom/home behaviors and academic performance, but showed minimal change on neuropsychological functioning in Taiwanese ADHD children. The finding of academic gain was unexpected, which might be due to the greater interest in achievement and better compliance to cultural expectations by Taiwanese versus Western students, which translated into more rapid improvement in academic performance.

  9. Performance improvement CME: managing schizophrenia.

    Science.gov (United States)

    Kane, John M; Correll, Christoph U

    2011-10-01

    Schizophrenia is a highly disabling disorder characterized by positive and negative symptoms and poor functioning in almost every area of life. Multiple antipsychotics have demonstrated varying levels of efficacy in reducing symptoms in schizophrenia, but adverse effects are common, adherence to medication is low, and relapse rates are high. Psychosocial interventions used in conjunction with antipsychotic pharmacotherapy may help improve treatment outcomes. This Performance Improvement CME activity focuses on individualizing treatment for schizophrenia, assessing treatment adherence, minimizing medication-induced adverse events, and preventing relapse, for children, adolescents, and adults with schizophrenia.

  10. Selective Attention, Anxiety, Depressive Symptomatology and Academic Performance in Adolescents

    Science.gov (United States)

    Fernandez-Castillo, Antonio; Gutierrez-Rojas, Maria Esperanza

    2009-01-01

    Introduction: In this cross-sectional, descriptive research we studied the relation between three psychological variables (anxiety, depression and attention) in order to analyze their possible association with and predictive power for academic achievement (as expressed in school grades) in a sample of secondary students. Method: For this purpose…

  11. Windows with improved energy performance

    DEFF Research Database (Denmark)

    Noyé, Peter Anders; Laustsen, Jacob Birck; Svendsen, Svend

    2002-01-01

    . Heat loss through windows represents a considerably part of the total heat loss from houses. However windows provide a unique potential of solar energy gain to the building besides from providing daylight access and view. This results in a need for development of windows with improved energy...... part, for which reason, as far as energy efficiency and total economy are concerned, it has become more interesting to further develop frame structures. Traditionally, the energy performance of windows has primarily been characterised by the heat loss coefficient, U-value. However as the heat loss has...... decreased the total solar energy transmittance, g-value, has become much more important since the solar gain through windows contributes to the heating of houses. This paper describes potential improvements of the window elements with respect to the overall energy performance of the window. Most importantly...

  12. Influence of Methylphenidate on Motor Performance and Attention in Children with Developmental Coordination Disorder and Attention Deficit Hyperactive Disorder

    Science.gov (United States)

    Bart, Orit; Daniel, Liron; Dan, Orrie; Bar-Haim, Yair

    2013-01-01

    Individuals with attention deficit hyperactive disorder (ADHD) often have coexisting developmental coordination disorder (DCD). The positive therapeutic effect of methylphenidate on ADHD symptoms is well documented, but its effects on motor coordination are less studied. We assessed the influence of methylphenidate on motor performance in children…

  13. Impact of Attention-Deficit Hyperactivity Disorder on School Performance: What are the Effects of Medication?

    Science.gov (United States)

    Baweja, Raman; Mattison, Richard E; Waxmonsky, James G

    2015-12-01

    Attention-deficit hyperactivity disorder (ADHD) affects an estimated 5-7 % of schoolchildren worldwide. School functioning and academic achievement are frequently impaired by ADHD and represent one of the main reasons children start ADHD medication. Multiple potential causal pathways exist between ADHD and impaired school performance. In this review, we decompose school performance into three components and assess the impact of ADHD and its treatments on academic performance (assessed by grade point average [GPA], time on-task, percentage of work completed as well as percent completed correctly), academic skills (as measured by achievement tests and cognitive measures), and academic enablers (such as study skills, motivation, engagement, classroom behavior and interpersonal skills). Most studies examined only the short-term effects of medication on school performance. In these, ADHD medications have been observed to improve some aspects of school performance, with the largest impact on measures of academic performance such as seatwork productivity and on-task performance. In a subset of children, these benefits may translate into detectable improvements in GPA and achievement testing. However, limited data exists to support whether these changes are sustained over years. Optimizing medication effects requires periodic reassessment of school performance, necessitating a collaborative effort involving patients, parents, school staff and prescribers. Even with systematic reassessment, behavioral-based treatments and additional school-based services may be needed to maximize academic performance for the many youth with ADHD and prominent impairments in school performance.

  14. An iPad-Based Tool for Improving the Skills of Children with Attention Deficit Disorder

    Directory of Open Access Journals (Sweden)

    Natalia Wrońska

    2015-06-01

    Full Text Available Attention Deficit Hyperactivity Disorder (ADHD, with a worldwide prevalence of 5.29%–7.1%, is one of the most common neurodevelopmental disorders among children and adolescents. Apart from typical symptoms like inattention, hyperactivity and impulsiveness, patients also evidence attention deficit problems with reading comprehension. This in turn causes poor school performance and widens the gap with peers without ADHD. This paper presents a novel and interactive tool based on Serious Games for Health, whose aim is not only to improve comprehension, but also hold the user’s attention. This tool is geared towards assessing reading quality and is intended for iPad devices. Preliminary results obtained from the experiment performed to evaluate the game are included in this report. A group of six typically developing children from Colegio Vizcaya aged between 8 and 12 took part in the evaluation of motivation, satisfaction and usability of the same therapy in the new media. Results obtained by participants playing the game were analysed together with questionnaires concerning the usability of the system. Game evaluation resulted in relatively good statistics-average score was 3 points out of 4 and average time for completing the exercise was 59 seconds. A SUS questionnaire with an average score of 92.75 out of 100 indicates that the game presented is user-friendly and an effective tool. Moreover, based on the feedback obtained from participants, the game had been improved and additional functionality introduced. Older participants completed the first game faster than the younger ones, but age was not influential in subsequent games.

  15. An iPad-Based Tool for Improving the Skills of Children with Attention Deficit Disorder.

    Science.gov (United States)

    Wrońska, Natalia; Garcia-Zapirain, Begonya; Mendez-Zorrilla, Amaia

    2015-06-02

    Attention Deficit Hyperactivity Disorder (ADHD), with a worldwide prevalence of 5.29%-7.1%, is one of the most common neurodevelopmental disorders among children and adolescents. Apart from typical symptoms like inattention, hyperactivity and impulsiveness, patients also evidence attention deficit problems with reading comprehension. This in turn causes poor school performance and widens the gap with peers without ADHD. This paper presents a novel and interactive tool based on Serious Games for Health, whose aim is not only to improve comprehension, but also hold the user's attention. This tool is geared towards assessing reading quality and is intended for iPad devices. Preliminary results obtained from the experiment performed to evaluate the game are included in this report. A group of six typically developing children from Colegio Vizcaya aged between 8 and 12 took part in the evaluation of motivation, satisfaction and usability of the same therapy in the new media. Results obtained by participants playing the game were analysed together with questionnaires concerning the usability of the system. Game evaluation resulted in relatively good statistics-average score was 3 points out of 4 and average time for completing the exercise was 59 seconds. A SUS questionnaire with an average score of 92.75 out of 100 indicates that the game presented is user-friendly and an effective tool. Moreover, based on the feedback obtained from participants, the game had been improved and additional functionality introduced. Older participants completed the first game faster than the younger ones, but age was not influential in subsequent games.

  16. Video game training to improve selective visual attention in older adults.

    Science.gov (United States)

    Belchior, Patrícia; Marsiske, Michael; Sisco, Shannon M; Yam, Anna; Bavelier, Daphne; Ball, Karlene; Mann, William C

    2013-07-01

    The current study investigated the effect of video game training on older adult's useful field of view performance (the UFOV® test). Fifty-eight older adult participants were randomized to receive practice with the target action game (Medal of Honor), a placebo control arcade game (Tetris), a clinically validated UFOV training program, or into a no contact control group. Examining pretest-posttest change in selective visual attention, the UFOV improved significantly more than the game groups; all three intervention groups improved significantly more than no-contact controls. There was a lack of difference between the two game conditions, differing from findings with younger adults. Discussion considers whether games posing less challenge might still be effective interventions for elders, and whether optimal training dosages should be higher.

  17. Improved power performance assessment methods

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, S.; Antoniou, I.; Dahlberg, J.A. [and others

    1999-03-01

    The uncertainty of presently-used methods for retrospective assessment of the productive capacity of wind farms is unacceptably large. The possibilities of improving the accuracy have been investigated and are reported. A method is presented that includes an extended power curve and site calibration. In addition, blockage effects with respect to reference wind speed measurements are analysed. It is found that significant accuracy improvements are possible by the introduction of more input variables such as turbulence and wind shear, in addition to mean wind speed and air density. Also, the testing of several or all machines in the wind farm - instead of only one or two - may provide a better estimate of the average performance. (au)

  18. Conjunctive Continuous Performance Task (CCPT)--A Pure Measure of Sustained Attention

    Science.gov (United States)

    Shalev, Lilach; Ben-Simon, Anat; Mevorach, Carmel; Cohen, Yoav; Tsal, Yehoshua

    2011-01-01

    Among the large variety of attentional tasks that have been used to study sustained attention, the Continuous Performance Task (CPT) is perhaps the most widely used. Despite substantial differences in task characteristics and demands, all CPT paradigms have been referred to as measures of sustained attention. In the present study we introduce a…

  19. College Students' Attention Behaviors during Independent Study and Course Level Academic Performance

    Science.gov (United States)

    Wagner, Linda G.

    2012-01-01

    Students in college make daily choices about how to use their independent study time, including choices about allocation of attention. Based on theoretical considerations and clinical studies, attention and the dividing of attention through multitasking is thought to have a relationship to performance levels. Research is only beginning to explore,…

  20. No age deficits in the ability to use attention to improve visual working memory.

    Science.gov (United States)

    Souza, Alessandra S

    2016-08-01

    Maintenance of information in mind to the moment-to-moment cognition is accomplished by working memory (WM). WM capacity is reduced in old age, but the nature of this decline is yet not clear. The current study examined the hypothesis that the decline in visual WM performance with age is related to a reduced ability to use attention to control the contents of WM. Young (M = 26 years) and old (M = 71 years) adults performed a color reproduction task in which the precise color of a set of dots had to be maintained in mind over a brief interval and later reproduced using a continuous color wheel. Attention was manipulated by presenting a spatial cue before the onset of the memory array (a precue) or during the maintenance phase (retro-cue). The cue indicated with 100% certainty the item to be tested at the end of the trial. A precue allows the selective encoding of only the relevant item to WM, whereas a retro-cue allows WM contents to be updated by refreshing the relevant (cued) item and removing nonrelevant (noncued) items. Aging was associated with a lower capacity in the baseline (no-cue) condition. Precues and (to a smaller extent) retro-cues improved WM performance (in terms of probability of recall and memory precision). Critically, the benefits of cueing were of similar magnitude in young and older adults showing that the ability to use attention to selectively encode and update the contents of WM is preserved with aging. (PsycINFO Database Record

  1. Incorporating modern neuroscience findings to improve brain-computer interfaces: tracking auditory attention

    Science.gov (United States)

    Wronkiewicz, Mark; Larson, Eric; Lee, Adrian KC

    2016-10-01

    Objective. Brain-computer interface (BCI) technology allows users to generate actions based solely on their brain signals. However, current non-invasive BCIs generally classify brain activity recorded from surface electroencephalography (EEG) electrodes, which can hinder the application of findings from modern neuroscience research. Approach. In this study, we use source imaging—a neuroimaging technique that projects EEG signals onto the surface of the brain—in a BCI classification framework. This allowed us to incorporate prior research from functional neuroimaging to target activity from a cortical region involved in auditory attention. Main results. Classifiers trained to detect attention switches performed better with source imaging projections than with EEG sensor signals. Within source imaging, including subject-specific anatomical MRI information (instead of using a generic head model) further improved classification performance. This source-based strategy also reduced accuracy variability across three dimensionality reduction techniques—a major design choice in most BCIs. Significance. Our work shows that source imaging provides clear quantitative and qualitative advantages to BCIs and highlights the value of incorporating modern neuroscience knowledge and methods into BCI systems.

  2. Working memory load can both improve and impair selective attention: evidence from the Navon paradigm.

    Science.gov (United States)

    Ahmed, Lubna; de Fockert, Jan W

    2012-10-01

    Selective attention to relevant targets has been shown to depend on the availability of working memory (WM). Under conditions of high WM load, processing of irrelevant distractors is enhanced. Here we showed that this detrimental effect of WM load on selective attention efficiency is reversed when the task requires global- rather than local-level processing. Participants were asked to attend to either the local or the global level of a hierarchical Navon stimulus while keeping either a low or a high load in WM. In line with previous findings, during attention to the local level, distractors at the global level produced more interference under high than under low WM load. By contrast, loading WM had the opposite effect of improving selective attention during attention to the global level. The findings demonstrate that the impact of WM load on selective attention is not invariant, but rather is dependent on the level of the to-be-attended information.

  3. F-35 Sustainment: Need for Affordable Strategy, Greater Attention to Risks, and Improved Cost Estimates

    Science.gov (United States)

    2014-09-01

    F - 35 SUSTAINMENT Need for Affordable Strategy, Greater Attention to Risks, and Improved Cost Estimates Report...2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE F - 35 Sustainment: Need for Affordable Strategy, Greater...House of Representatives September 2014 F - 35 SUSTAINMENT Need for Affordable Strategy, Greater Attention to Risks, and Improved Cost Estimates Why

  4. Caffeine regulates frontocorticostriatal dopamine transporter density and improves attention and cognitive deficits in an animal model of attention deficit hyperactivity disorder.

    Science.gov (United States)

    Pandolfo, Pablo; Machado, Nuno J; Köfalvi, Attila; Takahashi, Reinaldo N; Cunha, Rodrigo A

    2013-04-01

    Attention deficit hyperactivity disorder (ADHD) likely involves dopaminergic dysfunction in the frontal cortex and striatum, resulting in cognitive and motor abnormalities. Since both adenosine and dopamine modulation systems are tightly intertwined, we tested if caffeine (a non-selective adenosine receptor antagonist) attenuated the behavioral and neurochemical changes in adolescent spontaneously hypertensive rats (SHR, a validated ADHD animal model) compared to their control strain (Wistar Kyoto rats, WKY). SHR were hyperactive and had poorer performance in the attentional set-shifting and Y-maze paradigms and also displayed increased dopamine transporter (DAT) density and increased dopamine uptake in frontocortical and striatal terminals compared with WKY rats. Chronic caffeine treatment was devoid of effects in WKY rats while it improved memory and attention deficits and also normalized dopaminergic function in SHR. Additionally, we provide the first direct demonstration for the presence of adenosine A2A receptors (A2AR) in frontocortical nerve terminals, whose density was increased in SHR. These findings underscore the potential for caffeine treatment to normalize frontocortical dopaminergic function and to abrogate attention and cognitive changes characteristic of ADHD.

  5. Improving cardiac myocytes performance by CNTs platforms

    Directory of Open Access Journals (Sweden)

    Valentina eMartinelli

    2013-09-01

    Full Text Available The application of nanotechnology to the cardiovascular system has increasingly caught scientists’ attention as a potentially powerful tool for the development of new generation devices able to interface, repair or boost the performance of cardiac tissue. Carbon nanotubes (CNTs are considered as promising materials for nanomedicine applications in general and have been recently tested towards excitable cell growth. CNTs are cylindrically shaped structures made up of rolled-up graphene sheets, with unique electrical, thermal and mechanical properties, able to effectively conducting electrical current in electrochemical interfaces. CNTs-based scaffolds have been recently found to support the in vitro growth of cardiac cells: in particular, their ability to improve cardiomyocytes proliferation, maturation and electrical behavior are making CNTs extremely attractive for the development and exploitation of interfaces able to impact on cardiac cells physiology and function.

  6. St. John's wort may improve some symptoms of attention-deficit hyperactivity disorder.

    Science.gov (United States)

    Niederhofer, H

    2010-02-01

    There is evidence for the efficacy of noradrenaline and serotonin reuptake inhibitors treating attention-deficit hyperactivity disorder (ADHD). In this open trial, we checked St. John's wort, a serotonin and noradrealine reuptake inhibitor, and actually used as an antidepressant, for this indication. Three 14-16-year-old male psychiatric outpatients, diagnosed with ADHD have been rated at baseline and while taking St. John's wort or a placebo, respectively, by the Conner Scale and by the Continuous Performance Test, to determine its efficacy as a treatment option for ADHD. Patients' mean scores improved for Conners' hyperactivity, inattention and immaturity factors. Although the sample size is very small and therefore generalisation is very difficult, this observation indicates that St. John's wort might be a slightly effective treatment for ADHD also.

  7. Adaptive aspirations and performance heterogeneity : Attention allocation among multiple reference points

    NARCIS (Netherlands)

    Blettner, D.P.; He, Z.; Hu, S.; Bettis, R.

    2015-01-01

    Organizations learn and adapt their aspiration levels based on reference points (prior aspiration, prior performance, and prior performance of reference groups). The relative attention that organizations allocate to these reference points impacts organizational search and strategic decisions. Howeve

  8. Treatment with escitalopram improves the attentional bias toward negative facial expressions in patients with major depressive disorders.

    Science.gov (United States)

    Zhou, Zhenhe; Cao, Suxia; Li, Hengfen; Li, Youhui

    2015-10-01

    We hypothesized that treatment with escitalopram would improve cognitive bias and contribute to the recovery process for patients with major depressive disorder (MDD). Many previous studies have established that patients with MDD tend to pay selective attention to negative stimuli. The assessment of the level of cognitive bias is regarded as a crucial dimension of treatment outcomes for MDD. To our knowledge, no prior studies have been reported on the effects of treatment with escitalopram on attentional bias in MDD, employing a dot probe task of facial expression. We studied 25 patients with MDD and 25 controls, and used a dot probe task of facial expression to measure cognitive bias. The patients' psychopathologies were rated using the Hamilton Depression Scale (HAMD) at baseline and after 8 weeks of treatment with escitalopram. All participants performed the facial expression dot probe task. The results revealed that the 8 week escitalopram treatment decreased the HAMD scores. The patients with MDD at baseline exhibited an attentional bias towards negative faces, however, no significant bias toward either negative or happy faces were observed in the controls. After the 8 week escitalopram treatment, no significant bias toward negative faces was observed in the patient group. In conclusion, patients with MDD pay more attention to negative facial expressions, and treatment with escitalopram improves this attentional bias toward negative facial expressions. This is the first study, to our knowledge, on the effects of treatment with escitalopram on attentional bias in patients with MDD that has employed a dot probe task of facial expression.

  9. Computer-Detected Attention Affects Foreign Language Listening but Not Reading Performance.

    Science.gov (United States)

    Lee, Shu-Ping

    2016-08-01

    No quantitative study has explored the influence of attention on learning English as a foreign language (EFL). This study investigated whether computer-detected attention is associated with EFL reading and listening and reading and listening anxiety. Traditional paper-based English tests used as entrance examinations and tests of general trait anxiety, reading, listening, reading test state anxiety, and listening test state anxiety were administered in 252 Taiwan EFL college students who were divided into High Attention (Conners' Continuous Performance Test, CPT EFL students with computer-detected low attention tendency was elevated and their EFL listening performance was affected, but those differences were not found in reading.

  10. Memantine Improves Attentional Processes in Fragile X-Associated Tremor/Ataxia Syndrome: Electrophysiological Evidence from a Randomized Controlled Trial.

    Science.gov (United States)

    Yang, Jin-Chen; Rodriguez, Annette; Royston, Ashley; Niu, Yu-Qiong; Avar, Merve; Brill, Ryan; Simon, Christa; Grigsby, Jim; Hagerman, Randi J; Olichney, John M

    2016-02-22

    Progressive cognitive deficits are common in patients with fragile X-associated tremor/ataxia syndrome (FXTAS), with no targeted treatment yet established. In this substudy of the first randomized controlled trial for FXTAS, we examined the effects of NMDA antagonist memantine on attention and working memory. Data were analyzed for patients (24 in each arm) who completed both the primary memantine trial and two EEG recordings (at baseline and follow-up) using an auditory "oddball" task. Results demonstrated significantly improved attention/working memory performance after one year only for the memantine group. The event-related potential P2 amplitude elicited by non-targets was significantly enhanced in the treated group, indicating memantine-associated improvement in attentional processes at the stimulus identification/discrimination level. P2 amplitude increase was positively correlated with improvement on the behavioral measure of attention/working memory during target detection. Analysis also revealed that memantine treatment normalized the P2 habituation effect at the follow-up visit. These findings indicate that memantine may benefit attentional processes that represent fundamental components of executive function/dysfunction, thought to comprise the core cognitive deficit in FXTAS. The results provide evidence of target engagement of memantine, as well as therapeutically relevant information that could further the development of specific cognitive or disease-modifying therapies for FXTAS.

  11. Attentional Performance is Correlated with the Local Regional Efficiency of Intrinsic Brain Networks

    Directory of Open Access Journals (Sweden)

    Junhai eXu

    2015-07-01

    Full Text Available Attention is a crucial brain function for human beings. Using neuropsychological paradigms and task-based functional brain imaging, previous studies have indicated that widely distributed brain regions are engaged in three distinct attention subsystems: alerting, orienting and executive control (EC. Here, we explored the potential contribution of spontaneous brain activity to attention by examining whether resting-state activity could account for individual differences of the attentional performance in normal individuals. The resting-state functional images and behavioral data from attention network test (ANT task were collected in 59 healthy subjects. Graph analysis was conducted to obtain the characteristics of functional brain networks and linear regression analyses were used to explore their relationships with behavioral performances of the three attentional components. We found that there was no significant relationship between the attentional performance and the global measures, while the attentional performance was associated with specific local regional efficiency. These regions related to the scores of alerting, orienting and EC largely overlapped with the regions activated in previous task-related functional imaging studies, and were consistent with the intrinsic dorsal and ventral attention networks (DAN/VAN. In addition, the strong associations between the attentional performance and specific regional efficiency suggested that there was a possible relationship between the DAN/VAN and task performances in the ANT. We concluded that the intrinsic activity of the human brain could reflect the processing efficiency of the attention system. Our findings revealed a robust evidence for the functional significance of the efficiently organized intrinsic brain network for highly productive cognitions and the hypothesized role of the DAN/ VAN at rest.

  12. Stimulants improve theory of mind in children with attention deficit/hyperactivity disorder.

    Science.gov (United States)

    Maoz, Hagai; Tsviban, Lior; Gvirts, Hila Z; Shamay-Tsoory, Simone G; Levkovitz, Yechiel; Watemberg, Nathan; Bloch, Yuval

    2014-03-01

    Impairments in 'theory of mind' (ToM) were linked to social cognition and reciprocal relationships deficits in children with attention deficit/hyperactivity disorder (ADHD). Twenty-four children with ADHD (13 with inattentive type and 11 with combined type, mean age 10.2 years) completed the Interpersonal Reactivity Index (IRI), a self-reported empathy questionnaire. All children performed the 'faux pas' task and a computerized ToM task in two different sessions either with or without administration of methylphenidate (MPH). Administration of MPH was associated with an improvement in cognitive and affective ToM. Children with ADHD-combined type had significantly lower scores in total IRI and the fantasy scale compared to children with ADHD-inattentive type. We conclude that deficits in empathy and ToM may play an important role in the impairments in social cognition and peer relationship in children with ADHD, especially children a hyperactive component. Stimulants may improve ToM and empathic functions. Future studies including larger samples and additional cognitive tasks are warranted in order to generalize these results and to identify possible underlying mechanisms for improvement in ToM following the administration of MPH.

  13. Thoughts and attention of athletes under pressure: skill-focus or performance worries?

    Science.gov (United States)

    Oudejans, Raoul R D; Kuijpers, Wilma; Kooijman, Chris C; Bakker, Frank C

    2011-01-01

    Choking under pressure in sport has been explained by either explicit attention to skill execution (self-focus theories), or attention to performance worries (distraction theories). The aim of the present study was to find out which focus of attention occurs most often when expert athletes perform under pressure. Two retrospective methods were employed, namely, verbal reports and concept mapping. In the verbal reports, 70 expert athletes indicated their main focus of attention when performing under high pressure in competition. For concept mapping seven expert athletes generated statements about their focus of attention in such high-pressure situations. These statements were clustered and rated on how often they occurred and how important they were for choking. Both methods revealed that under pressure attention of expert athletes was often focused on worries and hardly ever on movement execution. Furthermore, the athletes reported that they focused attention on external factors and that they reverted to positive monitoring in an attempt to maintain performance. These results are more in line with distraction theories than self-focus theories, suggesting that attention to performance worries rather than to skill execution generally explains choking.

  14. Opportunities for Recognition Can Improve Learning and Performance

    Science.gov (United States)

    French, Ron; Henderson, Hester L.; Lavay, Barry; Silliman-French, Lisa

    2013-01-01

    Physical educators need to make an effort to catch students being good and recognize them for their positive accomplishments. Unfortunately, it is usually the students who act inappropriately who receive the majority of the teachers' attention. In order to help increase learning and improve performance and behavior, the physical educator must…

  15. Evaluating the Relationship between Team Performance and Joint Attention with Longitudinal Multivariate Mixed Models

    Science.gov (United States)

    2016-09-23

    models, with an emphasis on exploring the correlation structure between the variances in growth trajectories of team performance and joint attention...the correlation structure between the variances in growth trajectories of team performance and joint attention around estimated means. Observed...and transfer of human motor skills. Psychological Bulletin, 101(1), 41-74. Chung, S. (2015). Do friends perform better?: A meta-analytic review of

  16. Interpolated testing influences focused attention and improves integration of information during a video-recorded lecture.

    Science.gov (United States)

    Jing, Helen G; Szpunar, Karl K; Schacter, Daniel L

    2016-09-01

    Although learning through a computer interface has become increasingly common, little is known about how to best structure video-recorded lectures to optimize learning. In 2 experiments, we examine changes in focused attention and the ability for students to integrate knowledge learned during a 40-min video-recorded lecture. In Experiment 1, we demonstrate that interpolating a lecture with memory tests (tested group), compared to studying the lecture material for the same amount of time (restudy group), improves overall learning and boosts integration of related information learned both within individual lecture segments and across the entire lecture. Although mind wandering rates between the tested and restudy groups did not differ, mind wandering was more detrimental for final test performance in the restudy group than in the tested group. In Experiment 2, we replicate the findings of Experiment 1, and additionally show that interpolated tests influence the types of thoughts that participants report during the lecture. While the tested group reported more lecture-related thoughts, the restudy group reported more lecture-unrelated thoughts; furthermore, lecture-related thoughts were positively related to final test performance, whereas lecture-unrelated thoughts were negatively related to final test performance. Implications for the use of interpolated testing in video-recorded lectures are discussed. (PsycINFO Database Record

  17. Attention Performance Measured by Attention Network Test Is Correlated with Global and Regional Efficiency of Structural Brain Networks

    OpenAIRE

    Min Xiao; Haitao Ge; Budhachandra Singh Khundrakpam; Junhai Xu; Gleb Bezgin; Yuan Leng; Lu Zhao; Yuchun Tang; Xinting Ge; Seun Jeon; Wenjian Xu; Alan Charles Evans; Shuwei Liu

    2016-01-01

    Functional neuroimaging studies have indicated the involvement of separate brain areas in three distinct attention systems: alerting, orienting, and executive control (EC). However, the structural correlates underlying attention remains unexplored. Here, we utilized graph theory to examine the neuroanatomical substrates of the three attention systems measured by attention network test (ANT) in 65 healthy subjects. White matter connectivity, assessed with diffusion tensor imaging deterministic...

  18. Sustained Attention to Local and Global Target Features Is Different: Performance and Tympanic Membrane Temperature

    Science.gov (United States)

    Helton, William S.; Hayrynen, Lauren; Schaeffer, David

    2009-01-01

    Vision researchers have investigated the differences between global and local feature perception. No one has, however, examined the role of global and local feature discrimination in sustained attention tasks. In this experiment participants performed a sustained attention task requiring either global or local letter target discriminations or…

  19. Learning Behaviours, Attention and Anxiety in Caribbean Children: Beyond the 'Usual Suspects' in Explaining Academic Performance.

    Science.gov (United States)

    Durbrow, Eric H.; Schaefer, Barbara A.; Jimerson, Shane R.

    2000-01-01

    Contributions of learning behaviors; anxiety; attention problems; cognitive ability; and home background to academic performance was investigated in Caribbean village children (N=61). It was determined that anxiety, attention, and learning-related behaviors explained 32-35% of variance in academic scores. Results suggest that academic performance…

  20. Executive and Attentional Functions in Chronic Pain: Does Performance Decrease with Increasing Task Load?

    Directory of Open Access Journals (Sweden)

    Joukje M Oosterman

    2012-01-01

    Full Text Available 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.

  1. Improving Performance in a Nuclear Cardiology Department

    Science.gov (United States)

    LaFleur, Doug; Smalley, Karolyn; Austin, John

    2005-01-01

    Improving performance in the medical industry is an area that is ideally suited for the tools advocated by the International Society of Performance Improvement (ISPI). This paper describes an application of the tools that have been developed by Dale Brethower and Geary Rummler, two pillars of the performance improvement industry. It allows the…

  2. Four minutes of in-class high-intensity interval activity improves selective attention in 9- to 11-year olds.

    Science.gov (United States)

    Ma, Jasmin K; Le Mare, Lucy; Gurd, Brendon J

    2015-03-01

    The amount of time allocated to physical activity in schools is declining. Time-efficient physical activity solutions that demonstrate their impact on academic achievement-related outcomes are needed to prioritize physical activity within the school curricula. "FUNtervals" are 4-min, high-intensity interval activities that use whole-body actions to complement a storyline. The purpose of this study was to (i) explore whether FUNtervals can improve selective attention, an executive function posited to be essential for learning and academic success; and (ii) examine whether this relationship is predicted by students' classroom off-task behaviour. Seven grade 3-5 classes (n = 88) were exposed to a single-group, repeated cross-over design where each student's selective attention was compared between no-activity and FUNtervals days. In week 1, students were familiarized with the d2 test of attention and FUNterval activities, and baseline off-task behaviour was observed. In both weeks 2 and 3 students completed the d2 test of attention following either a FUNterval break or a no-activity break. The order of these breaks was randomized and counterbalanced between weeks. Neither motor nor passive off-task behaviour predicted changes in selective attention following FUNtervals; however, a weak relationship was observed for verbal off-task behaviour and improvements in d2 test performance. More importantly, students made fewer errors during the d2 test following FUNtervals. In supporting the priority of physical activity inclusion within schools, FUNtervals, a time efficient and easily implemented physical activity break, can improve selective attention in 9- to 11-year olds.

  3. Two Sudden Onsets Capture Attention but Do Not Improve Visual Short-Term Memory

    Directory of Open Access Journals (Sweden)

    Huang Chi-Hsiang

    2011-05-01

    Full Text Available Onset stimulus can capture attention and then transfer into visual short-term memory. It remains unknown whether two sudden onsets also capture attention and are stored in vSTM. We modified Belopolsky, Kramer, and Godijn's (2008 visual search paradigm to test this issue. Experiment 1 using one onset and replicated Belopolsky et al's results. Two onsets in Experiment 2 were found to capture attention; however, recognition performance for the onsets was only at chance level, showing poor memory. Experiment 3 used a retro-cue to test whether only one of these two onsets can be stored in vSTM. Experiment 4 tested whehter this poor recognition was caused by interference from meory probe. This study has important insights on how attention interacts with memory.

  4. Flow Experience During Attentional Training Improves Cognitive Functions in Patients with Traumatic Brain Injury: An Exploratory Case Study

    Directory of Open Access Journals (Sweden)

    Kazuki Yoshida

    2014-12-01

    Conclusion: The results for Patient A suggested that the flow task was more effective than general OT for improving attention deficits. Moreover, the results for Patient B suggested that the flow task was more effective than the control task. Attention training inducing flow experience may thus facilitate improvement of attention.

  5. Performance improvement. The American way.

    Science.gov (United States)

    Walker, Karen

    2007-02-15

    The role of a US-style 'improvement adviser' is to ensure chages are successfully implemented. They use coaching and facilitation to support project teams and are trained to overcome common obstacles. The advisers have advantages over traditional consultants, as they work with full inside knowledge of the organization and are there for the long-term.

  6. Attention, Visual Perception and their Relationship to Sport Performance in Fencing.

    Science.gov (United States)

    Hijazi, Mona Mohamed Kamal

    2013-12-18

    Attention and visual perception are important in fencing, as they affect the levels of performance and achievement in fencers. This study identifies the levels of attention and visual perception among male and female fencers and the relationship between attention and visual perception dimensions and the sport performance in fencing. The researcher employed a descriptive method in a sample of 16 fencers during the 2010/2011 season. The sample was comprised of eight males and eight females who participated in the 11-year stage of the Cairo Championships. The Test of Attentional and Interpersonal Style, which was designed by Nideffer and translated by Allawi (1998) was applied. The test consisted of 59 statements that measured seven dimensions. The Test of Visual Perception Skills designed by Alsmadune (2005), which includes seven dimensions was also used. Among females, a positive and statistically significant correlation between the achievement level and Visual Discrimination, Visual-Spatial Relationships, Visual Sequential Memory, Narrow Attentional Focus and Information Processing was observed, while among males, there was a positive and statistically significant correlation between the achievement level and Visual Discrimination, Visual Sequential Memory, Broad External Attentional Focus and Information Processing. For both males and females, a positive and statistically significant correlation between achievement level and Visual Discrimination, Visual Sequential Memory, Broad External Attentional, Narrow Attentional Focus and Information Processing was found. There were statistically significant differences between males and females in Visual Discrimination and Visual-Form Constancy.

  7. Benchmark for Strategic Performance Improvement.

    Science.gov (United States)

    Gohlke, Annette

    1997-01-01

    Explains benchmarking, a total quality management tool used to measure and compare the work processes in a library with those in other libraries to increase library performance. Topics include the main groups of upper management, clients, and staff; critical success factors for each group; and benefits of benchmarking. (Author/LRW)

  8. Room for Improvement: Performance Evaluations.

    Science.gov (United States)

    Webb, Gisela

    1989-01-01

    Describes a performance management approach to library personnel management that stresses communication, clarification of goals, and reinforcement of new practices and behaviors. Each phase of the evaluation process (preparation, rating, administrative review, appraisal interview, and follow-up) and special evaluations to be used in cases of…

  9. Contextual Cueing Improves Attentional Guidance, Even When Guidance Is Supposedly Optimal.

    Science.gov (United States)

    Harris, Anthony M; Remington, Roger W

    2017-02-23

    Visual search through previously encountered contexts typically produces reduced reaction times compared with search through novel contexts. This contextual cueing benefit is well established, but there is debate regarding its underlying mechanisms. Eye-tracking studies have consistently shown reduced number of fixations with repetition, supporting improvements in attentional guidance as the source of contextual cueing. However, contextual cueing benefits have been shown in conditions in which attentional guidance should already be optimal-namely, when attention is captured to the target location by an abrupt onset, or under pop-out conditions. These results have been used to argue for a response-related account of contextual cueing. Here, we combine eye tracking with response time to examine the mechanisms behind contextual cueing in spatially cued and pop-out conditions. Three experiments find consistent response time benefits with repetition, which appear to be driven almost entirely by a reduction in number of fixations, supporting improved attentional guidance as the mechanism behind contextual cueing. No differences were observed in the time between fixating the target and responding-our proxy for response related processes. Furthermore, the correlation between contextual cueing magnitude and the reduction in number of fixations on repeated contexts approaches 1. These results argue strongly that attentional guidance is facilitated by familiar search contexts, even when guidance is near-optimal. (PsycINFO Database Record

  10. Video game players show higher performance but no difference in speed of attention shifts.

    Science.gov (United States)

    Mack, David J; Wiesmann, Helene; Ilg, Uwe J

    2016-09-01

    Video games have become both a widespread leisure activity and a substantial field of research. In a variety of tasks, video game players (VGPs) perform better than non-video game players (NVGPs). This difference is most likely explained by an alteration of the basic mechanisms underlying visuospatial attention. More specifically, the present study hypothesizes that VGPs are able to shift attention faster than NVGPs. Such alterations in attention cannot be disentangled from changes in stimulus-response mappings in reaction time based measurements. Therefore, we used a spatial cueing task with varying cue lead times (CLTs) to investigate the speed of covert attention shifts of 98 male participants divided into 36 NVGPs and 62 VGPs based on their weekly gaming time. VGPs exhibited higher peak and mean performance than NVGPs. However, we did not find any differences in the speed of covert attention shifts as measured by the CLT needed to achieve peak performance. Thus, our results clearly rule out faster stimulus-response mappings as an explanation for the higher performance of VGPs in line with previous studies. More importantly, our data do not support the notion of faster attention shifts in VGPs as another possible explanation.

  11. Large-Scale Organizational Performance Improvement.

    Science.gov (United States)

    Pilotto, Rudy; Young, Jonathan O'Donnell

    1999-01-01

    Describes the steps involved in a performance improvement program in the context of a large multinational corporation. Highlights include a training program for managers that explained performance improvement; performance matrices; divisionwide implementation, including strategic planning; organizationwide training of all personnel; and the…

  12. Improving visual attention : the effect of Warning signs with different formats

    OpenAIRE

    Yao, Zheng; SUTO, Hidetsugu

    2015-01-01

    Designed warning signs were applied in this study to describe the performance of visual attention with different formats of stimulation. The dependent variables had be obtained from an eye movement experiment. A new proposal about how to sort experimental materials will be proposed.

  13. Performance improvement CME: managing chronic pain.

    Science.gov (United States)

    Fishman, Scott M

    2010-12-01

    Performance Improvement CME (PI CME) is an educational activity in which clinicians retrospectively assess their current clinical practice, choose areas for improvement and implement interventions based on treatment guidelines and health care standards, and then re-evaluate their clinical practice to assess the improvements made. This PI CME activity focuses on improving the safety and efficacy of treating chronic pain with opioid medications.

  14. Integration of proprioceptive signals and attentional capacity during postural control are impaired but subject to improvement in dyslexic children.

    Science.gov (United States)

    Quercia, Patrick; Demougeot, Laurent; Dos Santos, Mickaël; Bonnetblanc, François

    2011-04-01

    Children with developmental dyslexia suffer from delayed reading capabilities and may also exhibit attentional and sensori-motor deficits. The objective of this study was twofold. First, we aimed at investigating whether integration of proprioceptive signals in balance control was more impaired in dyslexic children when the attentional demand was varied. Secondly, we checked whether this effect was reduced significantly by using a specific treatment to improve eye control deficits and certain postural signs that are often linked to dyslexia (Quercia et al. in J Fr Ophtalmol 28:713-723, 2005, J Fr Ophtalmol 30:380-89, 2007). Thirty dyslexic and 51 treated dyslexic children (> 3 months of treatment) were compared with 42 non-dyslexic children in several conditions (mean age: 136.2 ± 23.6, 132.2 ± 18.7 and 140.2 ± 25 months, respectively). Co-vibration of ankle muscles was effected in order to alter proprioceptive information originating from the ankle. In two vibration conditions, ankle muscles were either not vibrated or vibrated at 85 Hz without illusion of any movement. These two vibration conditions were combined with two attentional conditions. In the first such condition, children maintained balance while merely fixing their gaze on a point in front of them. In the second condition, they had to look for smaller or larger stars in a panel showing forty of each kind. Balance was assessed by means of a force plate. Results indicated that the mean velocity (i.e. the total length) of the center of pressure (CoP) displacement in the 85-Hz vibration condition increased significantly more (compared with no vibration) in the dyslexic and the treated dyslexic groups than in the control group, irrespective of the attention task. Interestingly, in the condition without vibration, the attentional performance of treated children was similar to that of the control group, whereas the attentional performance of the untreated dyslexic children was significantly impaired

  15. Attention performance among Brazilian truck drivers and its association with amphetamine use: pilot study

    Directory of Open Access Journals (Sweden)

    Lucio Garcia de Oliveira

    2013-10-01

    Full Text Available The aim of this article was to describe the attention functioning of twenty-two truck drivers and its relationship with amphetamine use. Those drivers who reported using amphetamines in the twelve months previous to the interview had the best performance in a test evaluating sustained attention functioning. Although amphetamine use may initially seem advantageous to the drivers, it may actually impair safe driving. The findings suggest the importance of monitoring the laws regarding amphetamine use in this country.

  16. Attention and P300-based BCI performance in people with amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Angela eRiccio

    2013-11-01

    Full Text Available The purpose of this study was to investigate the support of attentional and memory processes in controlling a P300-based brain-computer interface (BCI in people suffering from amyotrophic lateral sclerosis (ALS. Eight people with ALS performed two behavioural tasks: i a rapid serial visual presentation (RSVP task, screening the temporal filtering capacity and the speed of the update of the attentive filter, and ii a change detection task, screening the memory capacity and the spatial filtering capacity. The participants were also asked to perform a P300-based BCI spelling task. By using correlation and regression analyses, we found that only the temporal filtering capacity in the RSVP task was a predictor of both the P300-based BCI accuracy and of the amplitude of the P300 elicited performing the BCI task. We concluded that the ability to keep the attentional filter active during the selection of a target influences performance in BCI control.

  17. The effect of organizational learning from performance feedback on team attention focus

    NARCIS (Netherlands)

    Lucas, G.J.M.; Zijlmans, Marius; Meeus, M.T.H.; Blettner, D.P.; Sund, K.J.; Galavan, R.J.; Huff, A.S.

    2016-01-01

    In this chapter, we present a theory on how organizational performance feedback influences individual decision-maker cognitions and thereby changes a team’s attention focus in terms of strategy. We argue that when performance compares unfavorably to aspiration levels, decision-makers reconsider curr

  18. Attention, temporal predictability, and the time course of context effects in naming performance

    NARCIS (Netherlands)

    Roelofs, Ardi

    2010-01-01

    Models of attention and context effects in naming performance should be able to account for the time course of color-word Stroop interference revealed by manipulations of the stimulus onset asynchrony (SOA) between color and word. Prominent models of Stroop task performance (Cohen, Dunbar, & McClell

  19. Effects of Attentional Focus and Age on Suprapostural Task Performance and Postural Control

    Science.gov (United States)

    McNevin, Nancy; Weir, Patricia; Quinn, Tiffany

    2013-01-01

    Purpose: Suprapostural task performance (manual tracking) and postural control (sway and frequency) were examined as a function of attentional focus, age, and tracking difficulty. Given the performance benefits often found under external focus conditions, it was hypothesized that external focus instructions would promote superior tracking and…

  20. Toward high performance, weakly invasive brain computer interfaces using selective visual attention.

    Science.gov (United States)

    Rotermund, David; Ernst, Udo A; Mandon, Sunita; Taylor, Katja; Smiyukha, Yulia; Kreiter, Andreas K; Pawelzik, Klaus R

    2013-04-01

    Brain-computer interfaces have been proposed as a solution for paralyzed persons to communicate and interact with their environment. However, the neural signals used for controlling such prostheses are often noisy and unreliable, resulting in a low performance of real-world applications. Here we propose neural signatures of selective visual attention in epidural recordings as a fast, reliable, and high-performance control signal for brain prostheses. We recorded epidural field potentials with chronically implanted electrode arrays from two macaque monkeys engaged in a shape-tracking task. For single trials, we classified the direction of attention to one of two visual stimuli based on spectral amplitude, coherence, and phase difference in time windows fixed relative to stimulus onset. Classification performances reached up to 99.9%, and the information about attentional states could be transferred at rates exceeding 580 bits/min. Good classification can already be achieved in time windows as short as 200 ms. The classification performance changed dynamically over the trial and modulated with the task's varying demands for attention. For all three signal features, the information about the direction of attention was contained in the γ-band. The most informative feature was spectral amplitude. Together, these findings establish a novel paradigm for constructing brain prostheses as, for example, virtual spelling boards, promising a major gain in performance and robustness for human brain-computer interfaces.

  1. Does attentional selectivity in the flanker task improve discretely or gradually?

    Directory of Open Access Journals (Sweden)

    Ronald eHübner

    2012-10-01

    Full Text Available An important question is whether attentional selectivity improves discretely or continuously during stimulus processing. In a recent study, Hübner, et al. (2010 found that the discrete DSTP model accounted better for flanker-task data than various continuous improvement models. However, in a subsequent study, White, et al. (2011 introduced the continuous SSP model and showed that it was superior to the DSTP model. From this result they concluded that attentional selectivity improves continuously rather than discretely. Because different stimuli and procedures were used in these two studies, though, we questioned that the superiority of the SSP model holds generally. Therefore, we fit the SSP model to Hübner et al.’s data and found that the DSTP model was again superior. A series of four experiments revealed that model superiority depends on the response-stimulus interval (RSI. Together, our results demonstrate that methodological details can be crucial for model selection, and that further comparisons between the models are needed before it can be decided whether attentional selectivity improves continuously or discretely.

  2. The moderating role of attention-deficit/hyperactivity disorder in the work engagement-performance process.

    Science.gov (United States)

    Halbesleben, Jonathon R B; Wheeler, Anthony R; Shanine, Kristen K

    2013-04-01

    Attention-deficit/hyperactivity disorder (ADHD) is a cognitive disability that affects millions. Although individuals with ADHD are employed throughout many organizations and there is evidence that their performance is lower, scant research exists describing how ADHD impacts an individual's performance. In this article, we extend attentional control theory to examine how ADHD impacts both the effectiveness and efficiency of employee performance. Across 3 samples, 2 of general working adults (n = 257 and 170) and 1 of nurses (n = 243), we found that ADHD was associated with lower performance (rated via self-, coworker, and supervisor ratings) and that the relationship was strongest for in-role performance, suggesting that employees with ADHD may be diverting attention away from task-relevant behaviors. Furthermore, although work engagement was associated with higher performance, that relationship was diminished among those who experienced higher levels of ADHD, suggesting lower performance efficiency. We discuss the implications of these findings for research on attentional control and the management of those with ADHD at work.

  3. Optimizing performance through intrinsic motivation and attention for learning: The OPTIMAL theory of motor learning.

    Science.gov (United States)

    Wulf, Gabriele; Lewthwaite, Rebecca

    2016-10-01

    Effective motor performance is important for surviving and thriving, and skilled movement is critical in many activities. Much theorizing over the past few decades has focused on how certain practice conditions affect the processing of task-related information to affect learning. Yet, existing theoretical perspectives do not accommodate significant recent lines of evidence demonstrating motivational and attentional effects on performance and learning. These include research on (a) conditions that enhance expectancies for future performance, (b) variables that influence learners' autonomy, and (c) an external focus of attention on the intended movement effect. We propose the OPTIMAL (Optimizing Performance through Intrinsic Motivation and Attention for Learning) theory of motor learning. We suggest that motivational and attentional factors contribute to performance and learning by strengthening the coupling of goals to actions. We provide explanations for the performance and learning advantages of these variables on psychological and neuroscientific grounds. We describe a plausible mechanism for expectancy effects rooted in responses of dopamine to the anticipation of positive experience and temporally associated with skill practice. Learner autonomy acts perhaps largely through an enhanced expectancy pathway. Furthermore, we consider the influence of an external focus for the establishment of efficient functional connections across brain networks that subserve skilled movement. We speculate that enhanced expectancies and an external focus propel performers' cognitive and motor systems in productive "forward" directions and prevent "backsliding" into self- and non-task focused states. Expected success presumably breeds further success and helps consolidate memories. We discuss practical implications and future research directions.

  4. Subjective evaluation of two stereoscopic imaging systems exploiting visual attention to improve 3D quality of experience

    Science.gov (United States)

    Hanhart, Philippe; Ebrahimi, Touradj

    2014-03-01

    Crosstalk and vergence-accommodation rivalry negatively impact the quality of experience (QoE) provided by stereoscopic displays. However, exploiting visual attention and adapting the 3D rendering process on the fly can reduce these drawbacks. In this paper, we propose and evaluate two different approaches that exploit visual attention to improve 3D QoE on stereoscopic displays: an offline system, which uses a saliency map to predict gaze position, and an online system, which uses a remote eye tracking system to measure real time gaze positions. The gaze points were used in conjunction with the disparity map to extract the disparity of the object-of-interest. Horizontal image translation was performed to bring the fixated object on the screen plane. The user preference between standard 3D mode and the two proposed systems was evaluated through a subjective evaluation. Results show that exploiting visual attention significantly improves image quality and visual comfort, with a slight advantage for real time gaze determination. Depth quality is also improved, but the difference is not significant.

  5. Improvements in concentration, working memory and sustained attention following consumption of a natural citicoline-caffeine beverage.

    Science.gov (United States)

    Bruce, Steven E; Werner, Kimberly B; Preston, Brittany F; Baker, Laurie M

    2014-12-01

    This study examined the neurocognitive and electrophysiological effects of a citicoline-caffeine-based beverage in 60 healthy adult participants enrolled in a randomized, double-blind, placebo-controlled trial. Measures of electrical brain activity using electroencephalogram (EEG) and neuropsychological measures examining attention, concentration and reaction time were administered. Compared to placebo, participants receiving the citicoline-caffeine beverage exhibited significantly faster maze learning times and reaction times on a continuous performance test, fewer errors in a go/no-go task and better accuracy on a measure of information processing speed. EEG results examining P450 event-related potentials revealed that participants receiving the citicoline-caffeine beverage exhibited higher P450 amplitudes than controls, suggesting an increase in sustained attention. Overall, these findings suggest that the beverage significantly improved sustained attention, cognitive effort and reaction times in healthy adults. Evidence of improved P450 amplitude indicates a general improvement in the ability to accommodate new and relevant information within working memory and overall enhanced brain activation.

  6. Attentional focus effects on sprint start performance as a function of skill level.

    Science.gov (United States)

    Ille, Anne; Selin, Ingrid; Do, Manh-Cuong; Thon, Bernard

    2013-01-01

    Several researchers have demonstrated that an external focus of attention (about movement's effects) during movement execution allowed better performances and learning of various motor tasks than an internal focus of attention (about movement itself). However, attentional focus effects have not been studied in tasks requiring explosive actions preceded by fast reaction time to a signal, such as a sprint start. We hypothesised that the beneficial effect of external focus of attention would be observed in the different stages of the sprint start (i.e., reaction time, block clearance and running) for both expert and novice sprinters. Novice and expert sprinters performed sprint starts followed by a 10 m sprint under three conditions: external focus instructions; internal focus instructions; and neutral instructions. The reaction time and the running time were significantly shorter in the external focus condition than in the internal focus condition, for both expert and novice participants. These results confirm the beneficial effect of an external focus of attention on the speed of movement execution. Moreover, they revealed that attentional focus influences movement preparation. Several hypotheses are proposed to account for these results, with reference to the processes that could be responsible for the observed effects.

  7. The Effect of Asterisks as an Attention Focusing Device on Test Performance of Undergraduate Students.

    Science.gov (United States)

    Perrin, David W.; Kerasotes, Dean L.

    It was hypothesized that using asterisks as attention focusing devices would cause students to read all asteriked test items more carefully and would improve test scores of undergraduate education students. Sixty-three undergraduates majoring in elementary or special education were administered a 36-item objective test. Asterisks were used to…

  8. Improving Working Memory in Children with Attention-Deficit/Hyperactivity Disorder: The Separate and Combined Effects of Incentives and Stimulant Medication

    Science.gov (United States)

    Strand, Michael T.; Hawk, Larry W., Jr.; Bubnik, Michelle; Shiels, Keri; Pelham, William E., Jr.; Waxmonsky, James G.

    2012-01-01

    Working memory (WM) is considered a core deficit in Attention-Deficit/Hyperactivity Disorder (ADHD), with numerous studies demonstrating impaired WM among children with ADHD. We tested the degree to which WM in children with ADHD was improved by performance-based incentives, an analog of behavioral intervention. In two studies, WM performance was…

  9. Beneficial outcome from EEG-neurofeedback on creative music performance, attention and well-being in school children.

    Science.gov (United States)

    Gruzelier, J H; Foks, M; Steffert, T; Chen, M J-L; Ros, T

    2014-01-01

    We earlier reported benefits for creativity in rehearsed music performance from alpha/theta (A/T) neurofeedback in conservatoire studies (Egner & Gruzelier, 2003) which were not found with SMR, Beta1, mental skills, aerobics or Alexander training, or in standby controls. Here the focus was the impact on novice music performance. A/T and SMR training were compared in 11-year old school children along with non-intervention controls with outcome measures not only of rehearsed music performance but also of creative improvisation, as well as sustained attention and phenomenology. Evidence of effective learning in the school setting was obtained for A/T and SMR/beta2 ratios. Preferential benefits from A/T for rehearsed music performance were replicated in children for technique and communication ratings. Benefits extended to creativity and communication ratings for creative improvisation which were shared with SMR training, disclosing an influence of SMR on unrehearsed music performance at a novice level with its greater cognitive demands. In a first application of A/T for improving sustained attention (TOVA), it was found to be more successful than SMR training, with a notable reduction in commission errors in the children, 15/33 of whom had attention indices in the ADHD range. Phenomenological reports were in favour of neurofeedback and well-being benefits. Implementing neurofeedback in the daily school setting proved feasible and holds pedagogic promise.

  10. Attention Performance Measured by Attention Network Test is Correlated with Global and Regional Efficiency of Structural Human Brain Networks

    Directory of Open Access Journals (Sweden)

    Min Xiao

    2016-10-01

    Full Text Available Functional neuroimaging studies have indicated the involvement of separate brain areas in three distinct attention systems: alerting, orienting and executive control (EC. However, the structural correlates underlying attention remains unexplored. Here, we utilized graph theory to examine the neuroanatomical substrates of the three attention systems measured by attention network test (ANT in 65 healthy subjects. White matter connectivity, assessed with DTI deterministic tractography was modeled as a structural network comprising 90 nodes defined by the Automated Anatomical Labeling (AAL template. Linear regression analyses were conducted to explore the relationship between topological parameters and the three attentional effects. We found a significant positive correlation between EC function and global efficiency of the whole brain network. At the regional level, node-specific correlations were discovered between regional efficiency and all three ANT components, including dorsolateral superior frontal gyrus, thalamus and parahippocampal gyrus for EC, thalamus and inferior parietal gyrus for alerting, and paracentral lobule and inferior occipital gyrus for orienting. Our findings highlight the fundamental architecture of interregional structural connectivity involved in attention and could provide new insights into the anatomical basis underlying human behavior.

  11. Sustained attention in intellectually gifted children assessed using a continuous performance test.

    Directory of Open Access Journals (Sweden)

    Jiannong Shi

    Full Text Available This study aimed to investigate two aspects of sustained attention in intellectually gifted children: first, the differences to intellectually average children; second, the differences between receiving standard education and enrichment education. Study 1 compared sustained attention between 24 intellectually gifted and 26 intellectually average children. The results showed that intellectually gifted children had better performance than their average peers, not only for the whole task but also on all indices. Study 2 compared sustained attention between 24 intellectually gifted children who received standard education and 24 intellectually gifted children who received enrichment education. The results showed that intellectually gifted children who received enrichment education performed better than those who received standard education. These findings are consistent with previous work and provide support for the implementation of enrichment education for intellectually gifted children.

  12. Long-term effects of attentional performance on functional brain network topology.

    Directory of Open Access Journals (Sweden)

    Thomas P K Breckel

    Full Text Available Individuals differ in their cognitive resilience. Less resilient people demonstrate a greater tendency to vigilance decrements within sustained attention tasks. We hypothesized that a period of sustained attention is followed by prolonged changes in the organization of "resting state" brain networks and that individual differences in cognitive resilience are related to differences in post-task network reorganization. We compared the topological and spatial properties of brain networks as derived from functional MRI data (N = 20 recorded for 6 mins before and 12 mins after the performance of an attentional task. Furthermore we analysed changes in brain topology during task performance and during the switches between rest and task conditions. The cognitive resilience of each individual was quantified as the rate of increase in response latencies over the 32-minute time course of the attentional paradigm. On average, functional networks measured immediately post-task demonstrated significant and prolonged changes in network organization compared to pre-task networks with higher connectivity strength, more clustering, less efficiency, and shorter distance connections. Individual differences in cognitive resilience were significantly correlated with differences in the degree of recovery of some network parameters. Changes in network measures were still present in less resilient individuals in the second half of the post-task period (i.e. 6-12 mins after task completion, while resilient individuals already demonstrated significant reductions of functional connectivity and clustering towards pre-task levels. During task performance brain topology became more integrated with less clustering and higher global efficiency, but linearly decreased with ongoing time-on-task. We conclude that sustained attentional task performance has prolonged, "hang-over" effects on the organization of post-task resting-state brain networks; and that more cognitively

  13. The influence of anaesthetists' experience on workload, performance and visual attention during simulated critical incidents.

    Science.gov (United States)

    Schulz, Christian M; Schneider, Erich; Kohlbecher, Stefan; Hapfelmeier, Alexander; Heuser, Fabian; Wagner, Klaus J; Kochs, Eberhard F; Schneider, Gerhard

    2014-10-01

    Development of accurate Situation Awareness (SA) depends on experience and may be impaired during excessive workload. In order to gain adequate SA for decision making and performance, anaesthetists need to distribute visual attention effectively. Therefore, we hypothesized that in more experienced anaesthetists performance is better and increase of physiological workload is less during critical incidents. Additionally, we investigated the relation between physiological workload indicators and distribution of visual attention. In fifteen anaesthetists, the increase of pupil size and heart rate was assessed in course of a simulated critical incident. Simulator log files were used for performance assessment. An eye-tracking device (EyeSeeCam) provided data about the anaesthetists' distribution of visual attention. Performance was assessed as time until definitive treatment. T tests and multivariate generalized linear models (MANOVA) were used for retrospective statistical analysis. Mean pupil diameter increase was 8.1% (SD ± 4.3) in the less experienced and 15.8% (±10.4) in the more experienced subjects (p = 0.191). Mean heart rate increase was 10.2% (±6.7) and 10.5% (±8.3, p = 0.956), respectively. Performance did not depend on experience. Pupil diameter and heart rate increases were associated with a shift of visual attention from monitoring towards manual tasks (not significant). For the first time, the following four variables were assessed simultaneously: physiological workload indicators, performance, experience, and distribution of visual attention between "monitoring" and "manual" tasks. However, we were unable to detect significant interactions between these variables. This experimental model could prove valuable in the investigation of gaining and maintaining SA in the operation theatre.

  14. A new test of attention in listening (TAIL predicts auditory performance.

    Directory of Open Access Journals (Sweden)

    Yu-Xuan Zhang

    Full Text Available Attention modulates auditory perception, but there are currently no simple tests that specifically quantify this modulation. To fill the gap, we developed a new, easy-to-use test of attention in listening (TAIL based on reaction time. On each trial, two clearly audible tones were presented sequentially, either at the same or different ears. The frequency of the tones was also either the same or different (by at least two critical bands. When the task required same/different frequency judgments, presentation at the same ear significantly speeded responses and reduced errors. A same/different ear (location judgment was likewise facilitated by keeping tone frequency constant. Perception was thus influenced by involuntary orienting of attention along the task-irrelevant dimension. When information in the two stimulus dimensions were congruent (same-frequency same-ear, or different-frequency different-ear, response was faster and more accurate than when they were incongruent (same-frequency different-ear, or different-frequency same-ear, suggesting the involvement of executive control to resolve conflicts. In total, the TAIL yielded five independent outcome measures: (1 baseline reaction time, indicating information processing efficiency, (2 involuntary orienting of attention to frequency and (3 location, and (4 conflict resolution for frequency and (5 location. Processing efficiency and conflict resolution accounted for up to 45% of individual variances in the low- and high-threshold variants of three psychoacoustic tasks assessing temporal and spectral processing. Involuntary orientation of attention to the irrelevant dimension did not correlate with perceptual performance on these tasks. Given that TAIL measures are unlikely to be limited by perceptual sensitivity, we suggest that the correlations reflect modulation of perceptual performance by attention. The TAIL thus has the power to identify and separate contributions of different components of

  15. Drawing students' attention to relevant assessment criteria: effects on self-assessment skills and performance

    NARCIS (Netherlands)

    Fastré, Greet; Van der Klink, Marcel; Sluijsmans, Dominique; Van Merriënboer, Jeroen

    2012-01-01

    Fastré, G. M. J., Van der Klink, M. R., Sluijsmans, D., & Van Merriënboer, J. J. G. (2012). Drawing students’ attention to relevant assessment criteria: effects on self-assessment skills and performance. Journal of Vocational Education & Training, 64(2), 185-198. doi:10.1080/13636820.2011.630537

  16. Under which conditions does T1 difficulty affect T2 performance in the attentional blink?

    DEFF Research Database (Denmark)

    Nielsen, Simon; Petersen, Anders; Andersen, Tobias Søren

    When two visual targets (T1 & T2) are presented in rapid succession, performance of T2 suffers up to 900 ms. One theory of this attentional blink (Raymond, Shapiro, & Arnell, 1992) propose that T1 and T2 compete for limited processing resources (Chun & Potter, 1995), and predict that prolonging...

  17. Performance-based interpretation bias in clinically anxious youths: relationships with attention, anxiety, and negative cognition.

    Science.gov (United States)

    Rozenman, Michelle; Amir, Nader; Weersing, V Robin

    2014-09-01

    This preliminary investigation sought to examine basic interpretive biases, as assessed via performance-based means, in the context of anxious symptomatology, attention, and negative cognition in children and adolescents. At a single assessment, 26 youths diagnosed with primary separation anxiety, social phobia, or generalized anxiety disorder completed performance-based assessments of interpretation and attention. Youths and parents also completed diagnostic interviews and youths completed a measure of negative self-statements. Components of interpretation (threat-valence judgments and speed of responding) were examined, and interpretation was explored as a correlate of youth anxiety, attention bias, and negative self-statements. Results found percentage of negative interpretations endorsed as the strongest predictor of anxiety symptoms; this index was also correlated with attention bias. Slower rejection of benign interpretations was also associated with youth-reported negative self-statements.This initial investigation provides support for a relationship between interpretation bias and anxiety and preliminary evidence for a relationship between attention and interpretation biases. Continued research dismantling the stages of basic cognition within the chain of information processing may provide a better understanding of the mechanisms underlying anxiety disorders in youths and lead to continued development and refinement of cognitive interventions.

  18. CHARACTERIZATION OF THE EFFECTS OF INHALED PERCHLOROETHYLENE ON SUSTAINED ATTENTION IN RATS PERFORMING A VISUAL SIGNAL DETECTION TASK

    Science.gov (United States)

    The aliphatic hydrocarbon perchloroethyelene (PCE) has been associated with neurobehavioral dysfunction including reduced attention in humans. The current study sought to assess the effects of inhaled PCE on sustained attention in rats performing a visual signal detection task (S...

  19. Carbohydrates, Muscle Glycogen, and Improved Performance.

    Science.gov (United States)

    Sherman, W. Mike

    1987-01-01

    One way to improve athletic performance without harming the athlete's health is diet manipulation. This article explores the relationship between muscular endurance and muscle glycogen and discusses a diet and training approach to competition. (Author/MT)

  20. Improving Process Heating System Performance v3

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-04-11

    Improving Process Heating System Performance: A Sourcebook for Industry is a development of the U.S. Department of Energy (DOE) Advanced Manufacturing Office (AMO) and the Industrial Heating Equipment Association (IHEA). The AMO and IHEA undertook this project as part of an series of sourcebook publications developed by AMO on energy-consuming industrial systems, and opportunities to improve performance. Other topics in this series include compressed air systems, pumping systems, fan systems, steam systems, and motors and drives

  1. Can sensory attention focused exercise facilitate the utilization of proprioception for improved balance control in PD?

    Science.gov (United States)

    Lefaivre, Shannon C; Almeida, Quincy J

    2015-02-01

    Impaired sensory processing in Parkinson's disease (PD) has been argued to contribute to balance deficits. Exercises aimed at improving sensory feedback and body awareness have the potential to ameliorate balance deficits in PD. Recently, PD SAFEx™, a sensory and attention focused rehabilitation program, has been shown to improve motor deficits in PD, although balance control has never been evaluated. The objective of this study was to measure the effects of PD SAFEx™ on balance control in PD. Twenty-one participants with mild to moderate idiopathic PD completed 12 weeks of PD SAFEx™ training (three times/week) in a group setting. Prior to training, participants completed a pre-assessment evaluating balance in accordance with an objective, computerized test of balance (modified clinical test of sensory integration and balance (m-CTSIB) and postural stability testing (PST)) protocols. The m-CTSIB was our primary outcome measure, which allowed assessment of balance in both eyes open and closed conditions, thus enabling evaluation of specific sensory contributions to balance improvement. At post-test, a significant interaction between time of assessment and vision condition (p=.014) demonstrated that all participants significantly improved balance control, specifically when eyes were closed. Balance control did not change from pre to post with eyes open. These results provide evidence that PD SAFEx™ is effective at improving the ability to utilize proprioceptive information, resulting in improved balance control in the absence of vision. Enhancing the ability to utilize proprioception for individuals with PD is an important intermediary to improving balance deficits.

  2. A performance study of the wavelet-phase stability (WPS) in auditory selective attention.

    Science.gov (United States)

    Low, Yin Fen; Strauss, Daniel J

    2011-08-10

    Large-scale neural correlates of auditory selective attention reflected in the electroencephalogram (EEG) have been identified by using the complex wavelet-phase stability measure (WPS). In this paper, we study the feasibility of using this amplitude independent measure, the WPS in extracting the correlates of attention by comparing its performance to the widely used linear interdependency measures, i.e., the wavelet coherence and the correlation coefficient. The outcome reveals that the WPS outperforms the other two measures in discriminating both the attended and unattended single sweep auditory late responses (ALRs). It is concluded that the proposed WPS provides a faster (in terms of less sweeps which are required) and robust objective quantification of selective attention.

  3. Methods to Improve Meat Performance on Yak

    Institute of Scientific and Technical Information of China (English)

    Yan P.; Xu B.Z.; Yang B,H.

    2005-01-01

    To compare the quality of yak meat with that of other livestock, the growth and development of yak from birth to 48-month old were measured, slaughter tests of 6-, 24-, 48-month old were made. It can improve meat performance on yak to crossbreed with beef cattle or wild yak, to improve traditional feeding and management, etc.

  4. Atypical Pulvinar-Cortical Pathways During Sustained Attention Performance in Children with Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Li, Xiaobo; Sroubek, Ariane; Kelly, Mary S.; Lesser, Iris; Sussman, Elyse; He, Yong; Branch, Craig; Foxe, John J.

    2012-01-01

    Objective: The neurobiological basis of inattentiveness, a core feature of attention-deficit/hyperactivity disorder (ADHD), is not yet well understood. Structural abnormalities in thalamus, especially the pulvinar nuclei, have recently been reported in ADHD. Pulvinar nuclei maintain reciprocal connections with cortical/subcortical areas, and play…

  5. Attention in Williams Syndrome and Down's Syndrome: Performance on the New Early Childhood Attention Battery

    Science.gov (United States)

    Breckenridge, Kate; Braddick, Oliver; Anker, Shirley; Woodhouse, Margaret; Atkinson, Janette

    2013-01-01

    Attentional problems are commonly reported as a feature of the behavioural profile in both Williams syndrome (WS) and Down's syndrome (DS). Recent studies have begun to investigate these impairments empirically, acknowledging the need for an approach that considers cross-syndrome comparisons and developmental changes across the different…

  6. Social isolation induces deficit of latent learning performance in mice: a putative animal model of attention deficit/hyperactivity disorder.

    Science.gov (United States)

    Ouchi, Hirofumi; Ono, Kazuya; Murakami, Yukihisa; Matsumoto, Kinzo

    2013-02-01

    Social isolation of rodents (SI) elicits a variety of stress responses such as increased aggressiveness, hyper-locomotion, and reduced susceptibility to pentobarbital. To obtain a better understanding of the relevance of SI-induced behavioral abnormalities to psychiatric disorders, we examined the effect of SI on latent learning as an index of spatial attention, and discussed the availability of SI as an epigenetic model of attention deficit hyperactivity disorder (ADHD). Except in specially stated cases, 4-week-old male mice were housed in a group or socially isolated for 3-70 days before experiments. The animals socially isolated for 1 week or more exhibited spatial attention deficit in the water-finding test. Re-socialized rearing for 5 weeks after 1-week SI failed to attenuate the spatial attention deficit. The effect of SI on spatial attention showed no gender difference or correlation with increased aggressive behavior. Moreover, SI had no effect on cognitive performance elucidated in a modified Y-maze or an object recognition test, but it significantly impaired contextual and conditional fear memory elucidated in the fear-conditioning test. Drugs used for ADHD therapy, methylphenidate (1-10 mg/kg, i.p.) and caffeine (0.5-1 mg/kg, i.p.), improved SI-induced latent learning deficit in a manner reversible with cholinergic but not dopaminergic antagonists. Considering the behavioral features of SI mice together with their susceptibility to ADHD drugs, the present findings suggest that SI provides an epigenetic animal model of ADHD and that central cholinergic systems play a role in the effect of methylphenidate on SI-induced spatial attention deficit.

  7. Peer Mentors Can Improve Academic Performance

    Science.gov (United States)

    Asgari, Shaki; Carter, Frederick, Jr.

    2016-01-01

    The present study examined the relationship between peer mentoring and academic performance. Students from two introductory psychology classes either received (n = 37) or did not receive (n = 36) peer mentoring. The data indicated a consistent improvement in the performance (i.e., grades on scheduled exams) of the mentored group. A similar pattern…

  8. Enhanced Visual-Attention Model for Perceptually Improved 3D Object Modeling in Virtual Environments

    Science.gov (United States)

    Chagnon-Forget, Maude; Rouhafzay, Ghazal; Cretu, Ana-Maria; Bouchard, Stéphane

    2016-12-01

    Three-dimensional object modeling and interactive virtual environment applications require accurate, but compact object models that ensure real-time rendering capabilities. In this context, the paper proposes a 3D modeling framework employing visual attention characteristics in order to obtain compact models that are more adapted to human visual capabilities. An enhanced computational visual attention model with additional saliency channels, such as curvature, symmetry, contrast and entropy, is initially employed to detect points of interest over the surface of a 3D object. The impact of the use of these supplementary channels is experimentally evaluated. The regions identified as salient by the visual attention model are preserved in a selectively-simplified model obtained using an adapted version of the QSlim algorithm. The resulting model is characterized by a higher density of points in the salient regions, therefore ensuring a higher perceived quality, while at the same time ensuring a less complex and more compact representation for the object. The quality of the resulting models is compared with the performance of other interest point detectors incorporated in a similar manner in the simplification algorithm. The proposed solution results overall in higher quality models, especially at lower resolutions. As an example of application, the selectively-densified models are included in a continuous multiple level of detail (LOD) modeling framework, in which an original neural-network solution selects the appropriate size and resolution of an object.

  9. A Combination Cocktail Improves Spatial Attention in a Canine Model of Human Aging and Alzheimer's disease

    Science.gov (United States)

    Head, Elizabeth; Murphey, Heather L.; Dowling, Amy L.S.; McCarty, Katie L.; Bethel, Samuel R.; Nitz, Jonathan A.; Pleiss, Melanie; Vanrooyen, Jenna; Grossheim, Mike; Smiley, Jeffery R.; Murphy, M. Paul; Beckett, Tina L.; Pagani, Dieter; Bresch, Frederick; Hendrix, Curt

    2014-01-01

    Alzheimer's disease (AD) involves multiple pathological processes in the brain, including increased inflammation and oxidative damage, as well as the accumulation of beta-amyloid (Aβ) plaques. We hypothesized that a combinatorial therapeutic approach to target these multiple pathways may provide cognitive and neuropathological benefits for AD patients. To test this hypothesis, we used a canine model of human aging and AD. Aged dogs naturally develop learning and memory impairments, human-type Aβ deposits and oxidative damage in the brain. Thus, 9 aged beagles (98-115 months) were treated with a medical food cocktail containing (1) an extract of turmeric containing 95% curcuminoids; (2) an extract of green tea containing 50% epigallocatechingallate; (3) N-acetyl cysteine; (4) R-alpha lipoic acid; and (5) an extract of black pepper containing 95% piperine. Nine similarly aged dogs served as placebo-treated controls. After 3 months of treatment, 13 dogs completed a variable distance landmark task used as a measure of spatial attention. As compared to placebo-treated animals, dogs receiving the medical food cocktail had significantly lower error scores (t(11)=4.3, p=0.001) and were more accurate across all distances (F(1,9)=20.7, p=0.001), suggesting an overall improvement in spatial attention. Measures of visual discrimination learning, executive function and spatial memory, and levels of brain and CSF Aβ were unaffected by the cocktail. Our results indicate that this medical food cocktail may be beneficial for improving spatial attention and motivation deficits associated with impaired cognition in aging and AD. PMID:22886019

  10. Effects of Diurnal Variation and Caffeine Consumption on Test of Variables of Attention (TOVA) Performance in Healthy Young Adults

    Science.gov (United States)

    Hunt, Melissa G.; Momjian, Ani J.; Wong, Keri K.

    2011-01-01

    The Test of Variables of Attention (TOVA) is a continuous performance test (CPT) that assesses attention, impulsivity, and processing speed. CPTs are used in the assessment of attention-deficit/hyperactivity disorder (ADHD) in children, but more young adults are being assessed for ADHD as well. The TOVA norms are based on a standardization sample…

  11. Attention Cueing and Activity Equally Reduce False Alarm Rate in Visual-Auditory Associative Learning through Improving Memory.

    Science.gov (United States)

    Nikouei Mahani, Mohammad-Ali; Haghgoo, Hojjat Allah; Azizi, Solmaz; Nili Ahmadabadi, Majid

    2016-01-01

    In our daily life, we continually exploit already learned multisensory associations and form new ones when facing novel situations. Improving our associative learning results in higher cognitive capabilities. We experimentally and computationally studied the learning performance of healthy subjects in a visual-auditory sensory associative learning task across active learning, attention cueing learning, and passive learning modes. According to our results, the learning mode had no significant effect on learning association of congruent pairs. In addition, subjects' performance in learning congruent samples was not correlated with their vigilance score. Nevertheless, vigilance score was significantly correlated with the learning performance of the non-congruent pairs. Moreover, in the last block of the passive learning mode, subjects significantly made more mistakes in taking non-congruent pairs as associated and consciously reported lower confidence. These results indicate that attention and activity equally enhanced visual-auditory associative learning for non-congruent pairs, while false alarm rate in the passive learning mode did not decrease after the second block. We investigated the cause of higher false alarm rate in the passive learning mode by using a computational model, composed of a reinforcement learning module and a memory-decay module. The results suggest that the higher rate of memory decay is the source of making more mistakes and reporting lower confidence in non-congruent pairs in the passive learning mode.

  12. AULA virtual reality test as an attention measure: convergent validity with Conners' Continuous Performance Test.

    Science.gov (United States)

    Díaz-Orueta, Unai; Garcia-López, Cristina; Crespo-Eguílaz, Nerea; Sánchez-Carpintero, Rocío; Climent, Gema; Narbona, Juan

    2014-01-01

    The majority of neuropsychological tests used to evaluate attention processes in children lack ecological validity. The AULA Nesplora (AULA) is a continuous performance test, developed in a virtual setting, very similar to a school classroom. The aim of the present study is to analyze the convergent validity between the AULA and the Continuous Performance Test (CPT) of Conners. The AULA and CPT were administered correlatively to 57 children, aged 6-16 years (26.3% female) with average cognitive ability (IQ mean = 100.56, SD = 10.38) who had a diagnosis of attention deficit/hyperactivity disorder (ADHD) according to DSM-IV-TR criteria. Spearman correlations analyses were conducted among the different variables. Significant correlations were observed between both tests in all the analyzed variables (omissions, commissions, reaction time, and variability of reaction time), including for those measures of the AULA based on different sensorial modalities, presentation of distractors, and task paradigms. Hence, convergent validity between both tests was confirmed. Moreover, the AULA showed differences by gender and correlation to Perceptual Reasoning and Working Memory indexes of the WISC-IV, supporting the relevance of IQ measures in the understanding of cognitive performance in ADHD. In addition, the AULA (but not Conners' CPT) was able to differentiate between ADHD children with and without pharmacological treatment for a wide range of measures related to inattention, impulsivity, processing speed, motor activity, and quality of attention focus. Additional measures and advantages of the AULA versus Conners' CPT are discussed.

  13. Differential reinforcement and resistance to change of divided-attention performance.

    Science.gov (United States)

    Podlesnik, Christopher A; Thrailkill, Eric; Shahan, Timothy A

    2012-06-01

    Behavioral momentum theory provides a framework for understanding how conditions of reinforcement influence instrumental response strength under conditions of disruption (i.e., resistance to change). The present experiment examined resistance to change of divided-attention performance when different overall probabilities of reinforcement were arranged across two components of a multiple schedule. Pigeons responded in a delayed-matching-to-sample procedure with compound samples (color + line orientation) and element comparisons (two colors or two line orientations). Reinforcement ratios of 1:9, 1:1, and 9:1 for accurate matches on the two types of comparison trials were examined across conditions using reinforcement probabilities (color/lines) of .9/.1, .5/.5, and .1/.9 in the rich component and .18/.02, .1/.1, and .02/.18 in the lean component. Relative accuracy with color and line comparisons was an orderly function of relative reinforcement, but this relation did not depend on the overall rate of reinforcement between components. The resistance to change of divided-attention performance was greater for both trial types in the rich component with presession feeding and extinction, but not with decreases in sample duration. These findings suggest promise for the applicability of quantitative models of operant behavior to divided-attention performance, but they highlight the need to further explore conditions impacting the resistance to change of attending.

  14. Improving Dorsal Stream Function in Dyslexics by Training Figure/Ground Motion Discrimination Improves Attention, Reading Fluency, and Working Memory

    Science.gov (United States)

    Lawton, Teri

    2016-01-01

    There is an ongoing debate about whether the cause of dyslexia is based on linguistic, auditory, or visual timing deficits. To investigate this issue three interventions were compared in 58 dyslexics in second grade (7 years on average), two targeting the temporal dynamics (timing) of either the auditory or visual pathways with a third reading intervention (control group) targeting linguistic word building. Visual pathway training in dyslexics to improve direction-discrimination of moving test patterns relative to a stationary background (figure/ground discrimination) significantly improved attention, reading fluency, both speed and comprehension, phonological processing, and both auditory and visual working memory relative to controls, whereas auditory training to improve phonological processing did not improve these academic skills significantly more than found for controls. This study supports the hypothesis that faulty timing in synchronizing the activity of magnocellular with parvocellular visual pathways is a fundamental cause of dyslexia, and argues against the assumption that reading deficiencies in dyslexia are caused by phonological deficits. This study demonstrates that visual movement direction-discrimination can be used to not only detect dyslexia early, but also for its successful treatment, so that reading problems do not prevent children from readily learning. PMID:27551263

  15. Performance improvement with patient service partners.

    Science.gov (United States)

    Burns, J P

    1998-01-01

    Once the decision is made to use a patient-focused care delivery system, a variety of methods can be used to successfully design the model. The author describes the process used by a multilevel, multidisciplinary team at a community hospital to design and implement a Service Partner role that would meet and exceed customer expectations. Demonstrated performance improvements included increased patient satisfaction, productive labor dollar savings, and improvements in the work environment for staff members.

  16. The Effectiveness of a Joint Attention Training Program on Improving Communication Skills of Children with Autism Spectrum Disorder

    Science.gov (United States)

    Eissa, Mourad Ali

    2015-01-01

    The purpose of this study was to explore the effect of a joint attention intervention program on improving joint attention and communication skills in children with autism disorder. Participants were ten children between the ages of five and seven who attended a school for children with developmental disabilities (Tarbya Fekrya ). A pre-post…

  17. Improving human performance in maintenance personnel

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Anez, Francisco [Maintenance Training Centre, TECNATOM, S.A, Avd. Montes de Oca, 1. 28709-San Sebastian de los Reyes, Madrid (Spain); Agueero Agueero, Jorge [Technologic Institute, TECNATOM, S.A, Avd. Montes de Oca, 1. 28709-San Sebastian de los Reyes, Madrid (Spain)

    2010-07-01

    The continuous evolution and improvement of safety-related processes has included the analysis, design and development of training plans for the qualification of maintenance nuclear power plant personnel. In this respect, the international references in this area recommend the establishment of systematic qualification programmes for personnel performing functions or carrying out safety related tasks. Maintenance personnel qualification processes have improved significantly, and training plans have been designed and developed based on Systematic Approach to Training methodology to each job position. These improvements have been clearly reflected in recent training programmes with new training material and training facilities focused not only on developing technical knowledge and skills but also on improving attitudes and safety culture. The objectives of maintenance training facilities such as laboratories, mock-ups real an virtual, hydraulic loops, field simulators and other training material to be used in the maintenance training centre are to cover training necessities for initial and continuous qualification. Evidently, all these improvements made in the qualification of plant personnel should be extended to include supplemental personnel (external or contracted) performing safety-related tasks. The supplemental personnel constitute a very spread group, covering the performance of multiple activities entailing different levels of responsibility. Some of these activities are performed permanently at the plant, while others are occasional or sporadic. In order to establish qualification requirements for these supplemental workers, it is recommended to establish a rigorous analysis of job positions and tasks. The objective will be to identify the qualification requirements to assure competence and safety. (authors)

  18. An Adaptive Middleware for Improved Computational Performance

    DEFF Research Database (Denmark)

    Bonnichsen, Lars Frydendal

    The performance improvements in computer systems over the past 60 years have been fueled by an exponential increase in energy efficiency. In recent years, the phenomenon known as the end of Dennard’s scaling has slowed energy efficiency improvements — but improving computer energy efficiency...... is more important now than ever. Traditionally, most improvements in computer energy efficiency have come from improvements in lithography — the ability to produce smaller transistors — and computer architecture - the ability to apply those transistors efficiently. Since the end of scaling, we have seen...... diminishing returns from developments in lithography and modern computer architectures are so complicated requiring significant programming effort to exploit efficiently —software developers undertaking such a task will need all the help they can get, in order to keep the programming effort down...

  19. Measuring the Performance of Attention Networks with the Dalhousie Computerized Attention Battery (DalCAB): Methodology and Reliability in Healthy Adults.

    Science.gov (United States)

    Jones, Stephanie A H; Butler, Beverly C; Kintzel, Franziska; Johnson, Anne; Klein, Raymond M; Eskes, Gail A

    2016-01-01

    Attention is an important, multifaceted cognitive domain that has been linked to three distinct, yet interacting, networks: alerting, orienting, and executive control. The measurement of attention and deficits of attention within these networks is critical to the assessment of many neurological and psychiatric conditions in both research and clinical settings. The Dalhousie Computerized Attention Battery (DalCAB) was created to assess attentional functions related to the three attention networks using a range of tasks including: simple reaction time, go/no-go, choice reaction time, dual task, flanker, item and location working memory, and visual search. The current study provides preliminary normative data, test-retest reliability (intraclass correlations) and practice effects in DalCAB performance 24-h after baseline for healthy young adults (n = 96, 18-31 years). Performance on the DalCAB tasks demonstrated Good to Very Good test-retest reliability for mean reaction time, while accuracy and difference measures (e.g., switch costs, interference effects, and working memory load effects) were most reliable for tasks that require more extensive cognitive processing (e.g., choice reaction time, flanker, dual task, and conjunction search). Practice effects were common and pronounced at the 24-h interval. In addition, performance related to specific within-task parameters of the DalCAB sub-tests provides preliminary support for future formal assessment of the convergent validity of our interpretation of the DalCAB as a potential clinical and research assessment tool for measuring aspects of attention related to the alerting, orienting, and executive control networks.

  20. Improvement in Attention and Executive Functions During Isotretinoin Treatment in Patients With Acne

    Directory of Open Access Journals (Sweden)

    Erdem Deveci

    2013-05-01

    Full Text Available Background and Design: We assessed attention, memory, verbal-linguistic ability, and executive functions in acne vulgaris patients before and during isotretinoin treatment.Materials and Methods: Fifty-two treatment-naive acne patients at baseline and 24 at the second visit were evaluated. A neurocognitive battery including the Rey Auditory Verbal Learning and Memory Test, Auditory Consonant Trigram Test, Controlled Word Association Test, Digit Span Test, Trail Making Test A and B and the Stroop Test was used. The Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I, Hospital Anxiety and Depression Scale (HADS, and the Liebowitz Social Anxiety Scale (LSAS were also applied.Results: We found improvements in attention and executive functions at the second visit in comparison with the baseline evaluations. No alteration was found in verbal episodic memory, learning, working memory, and phonemic verbal fluency (Digit Span Forwards Test p=0.003, Trial Making-A Test p=0.002, Trial Making –B Test p=0.000, Stroop test p=0.028.Discussion: The positive effects of isotretinoin on cognitive functions may be related to the decline in acne lesions and less mental occupation with the social impacts of acne.

  1. Complex living conditions impair behavioral inhibition but improve attention in rats

    Directory of Open Access Journals (Sweden)

    Rixt evan der Veen

    2015-12-01

    Full Text Available Rapid adaptation to changes, while maintaining a certain level of behavioral inhibition is an important feature in every day functioning. How environmental context and challenges in life can impact on the development of this quality is still unknown. In the present study, we examined the effect of a complex rearing environment during adolescence on attention and behavioral inhibition in adult male rats. We also tested whether these effects were affected by an adverse early life challenge, maternal deprivation. We found that animals that were raised in large, two floor MarlauTM cages, together with 10 conspecifics, showed improved attention, but impaired behavioral inhibition in the 5-choice serial reaction time task. The early life challenge of 24h maternal deprivation on postnatal day 3 led to a decline in bodyweight during adolescence, but did not by itself influence responses in the 5-choice task in adulthood, nor did it moderate the effects of complex housing. Our data suggest that a complex rearing environment leads to a faster adaptation to changes in the environment, but at the cost of lower behavioral inhibition.

  2. Methods to improve joint attention in young children with autism: a review

    Directory of Open Access Journals (Sweden)

    Paparella T

    2015-05-01

    Full Text Available Tanya Paparella, Stephanny F N Freeman Department of Child Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, USA Abstract: We provide an overview of studies in the past 10 years (2004–2014 that have aimed to improve joint attention (JA in young children at risk for, or with, autism spectrum disorder. Thirteen randomized controlled trial (RCT interventions were found, which received particular focus. Three studies used intervention methods with a developmental orientation and focused on caregiver-mediated methods. Others used combined developmental and behavioral approaches and delivered intervention via trained interventionists, caregivers, and teachers. Interventions ranged widely in density, both with respect to the amount of intervention delivered weekly and the total duration of intervention. Fourteen single-subject research design (SSRD studies and one quasi-experimental pre–post design study were also included. Notably absent in the RCTs were studies using only behavioral methods, while behavioral methods dominated in the SSRDs. The outcomes of the RCTs using combined behavioral and developmental methods generally demonstrate short-term social communication gains. While some studies demonstrated long-term maintenance and positive outcomes in related areas such as language, many did not. The mixed results for language outcomes indicate a need for further investigation. In addition, future studies should further examine participants' developmental readiness and intervention dose in relation to outcome, as well as aim to isolate active ingredients of interventions. Keywords: intervention, joint attention, joint engagement, language, randomized controlled trial

  3. Electrolysis Performance Improvement and Validation Experiment

    Science.gov (United States)

    Schubert, Franz H.

    1992-01-01

    Viewgraphs on electrolysis performance improvement and validation experiment are presented. Topics covered include: water electrolysis: an ever increasing need/role for space missions; static feed electrolysis (SFE) technology: a concept developed for space applications; experiment objectives: why test in microgravity environment; and experiment description: approach, hardware description, test sequence and schedule.

  4. Improving the Dictation in Attention Deficit Hyperactivity Disorder by Using Computer Based Interventions: A Clinical Trial

    Directory of Open Access Journals (Sweden)

    Mahdi Tehranidoost

    2006-07-01

    Full Text Available Objective: The aim of the current study was to assess the impact of computer games and computer-assisted type instruction on dictation scores of elementary school children with attention deficit – hyperactivity disorder (ADHD. Method: In this single-blind clinical trial, 37 elementary school children with ADHD, selected by convenience sampling and divided into group I (n=17 and group II (n=20, underwent eight one-hour sessions (3 sessions per week of intervention by computer games versus computer-assisted type instruction, respectively. 12 school dictation scores were considered: 4 scores preintervention, 4 scores during interventions, and 4 scores post-intervention. Dictation test was taken during each session. Data was analyzed using repeated measure ANOVA. Results: Two groups were matched for age, gender, school grade, medication, IQ, parent’s and teacher’s Conners’ scale scores, having computer at home, history of working with computer, and mean dictation scores. There was no significant difference in dictation scores before and after interventions and also between the study groups. The improvement in school dictation scores had no significant correlation with age, gender, Ritalin use, owning a computer at home and past history of computer work, baseline dictation scores, Ritalin dose, educational status, IQ, and the total score of parent’s and teacher’s Conners’ rating scale. Conclusion: Absence of significant improvement in dictation scores in study groups may be due to the confounding effect of other variables with known impact on dictation scores. Further studies in this field should also assess the change of attention and memory.

  5. Improved sensorimotor performance via stochastic resonance.

    Science.gov (United States)

    Mendez-Balbuena, Ignacio; Manjarrez, Elias; Schulte-Mönting, Jürgen; Huethe, Frank; Tapia, Jesus A; Hepp-Reymond, Marie-Claude; Kristeva, Rumyana

    2012-09-01

    Several studies about noise-enhanced balance control in humans support the hypothesis that stochastic resonance can enhance the detection and transmission in sensorimotor system during a motor task. The purpose of the present study was to extend these findings in a simpler and controlled task. We explored whether a particular level of a mechanical Gaussian noise (0-15 Hz) applied on the index finger can improve the performance during compensation for a static force generated by a manipulandum. The finger position was displayed on a monitor as a small white point in the center of a gray circle. We considered a good performance when the subjects exhibited a low deviation from the center of this circle and when the performance had less variation over time. Several levels of mechanical noise were applied on the manipulandum. We compared the performance between zero noise (ZN), optimal noise (ON), and high noise (HN). In all subjects (8 of 8) the data disclosed an inverted U-like graph between the inverse of the mean variation in position and the input noise level. In other words, the mean variation was significantly smaller during ON than during ZN or HN. The findings suggest that the application of a tactile-proprioceptive noise can improve the stability in sensorimotor performance via stochastic resonance. Possible explanations for this improvement in motor precision are an increase of the peripheral receptors sensitivity and of the internal stochastic resonance, causing a better sensorimotor integration and an increase in corticomuscular synchronization.

  6. Verbal communication improves laparoscopic team performance.

    Science.gov (United States)

    Shiliang Chang; Waid, Erin; Martinec, Danny V; Bin Zheng; Swanstrom, Lee L

    2008-06-01

    The impact of verbal communication on laparoscopic team performance was examined. A total of 24 dyad teams, comprised of residents, medical students, and office staff, underwent 2 team tasks using a previously validated bench model. Twelve teams (feedback groups) received instant verbal instruction and feedback on their performance from an instructor which was compared with 12 teams (control groups) with minimal or no verbal feedback. Their performances were both video and audio taped for analysis. Surgical backgrounds were similar between feedback and control groups. Teams with more verbal feedback achieved significantly better task performance (P = .002) compared with the control group with less feedback. Impact of verbal feedback was more pronounced for tasks requiring team cooperation (aiming and navigation) than tasks depending on individual skills (knotting). Verbal communication, especially the instructions and feedback from an experienced instructor, improved team efficiency and performance.

  7. Improving DNA vaccine performance through vector design.

    Science.gov (United States)

    Williams, James A

    2014-01-01

    DNA vaccines are a rapidly deployed next generation vaccination platform for treatment of human and animal disease. DNA delivery devices, such as electroporation and needle free jet injectors, are used to increase gene transfer. This results in higher antigen expression which correlates with improved humoral and cellular immunity in humans and animals. This review highlights recent vector and transgene design innovations that improve DNA vaccine performance. These new vectors improve antigen expression, increase plasmid manufacturing yield and quality in bioreactors, and eliminate antibiotic selection and other potential safety issues. A flowchart for designing synthetic antigen transgenes, combining antigen targeting, codon-optimization and bioinformatics, is presented. Application of improved vectors, of antibiotic free plasmid production, and cost effective manufacturing technologies will be critical to ensure safety, efficacy, and economically viable manufacturing of DNA vaccines currently under development for infectious disease, cancer, autoimmunity, immunotolerance and allergy indications.

  8. Effects of diurnal variation on the Test of Variables of Attention performance in young adults with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Hunt, Melissa G; Bienstock, Solomon W; Qiang, Judy Kexin

    2012-03-01

    The Test of Variables of Attention (TOVA) is a continuous performance test that assesses attention, impulsivity, and processing speed. Continuous performance tests are used in the assessment of attention-deficit/hyperactivity disorder (ADHD) in children and adults. TOVA norms are based on a morning administration, and any TOVA administered after 1:00 p.m. is flagged as potentially invalid. Whereas the testing time recommendations make sense for pediatric samples, it is unclear whether they are appropriate for young adults, who typically show significant phase delay in their diurnal rhythms. The current study explores the impact of time of day on TOVA performance in young adults with ADHD. Participants were randomly assigned to either morning or afternoon administration. We found no significant diurnal variation in TOVA performance. We also found no interaction between diurnal preference and time of day of administration. Night owls endorsed more inattention symptoms on a self-report measure than more intermediate individuals but actually made significantly fewer omission (inattention) errors on the TOVA. Self-reported symptoms of inattention showed moderate, significant correlations with various TOVA performance indices. Self-reported symptoms of hyperactivity and impulsivity, however, showed no relationship to TOVA performance. These results suggest that the TOVA can be administered to adults with ADHD outside of the hours recommended in the manual without significantly compromising the interpretative validity of test score interpretation. Thus, a TOVA report that is consistent with ADHD should not be dismissed simply because it was administered in the late afternoon.

  9. Improving performance via mini-applications.

    Energy Technology Data Exchange (ETDEWEB)

    Crozier, Paul Stewart; Thornquist, Heidi K.; Numrich, Robert W. (University of Minnesota, Minneapolis, MN); Williams, Alan B.; Edwards, Harold Carter; Keiter, Eric Richard; Rajan, Mahesh; Willenbring, James M.; Doerfler, Douglas W.; Heroux, Michael Allen

    2009-09-01

    Application performance is determined by a combination of many choices: hardware platform, runtime environment, languages and compilers used, algorithm choice and implementation, and more. In this complicated environment, we find that the use of mini-applications - small self-contained proxies for real applications - is an excellent approach for rapidly exploring the parameter space of all these choices. Furthermore, use of mini-applications enriches the interaction between application, library and computer system developers by providing explicit functioning software and concrete performance results that lead to detailed, focused discussions of design trade-offs, algorithm choices and runtime performance issues. In this paper we discuss a collection of mini-applications and demonstrate how we use them to analyze and improve application performance on new and future computer platforms.

  10. Yizhining elixation improves sustained attention deficit and impulsiveness of spontaneous hypertensive rats

    Institute of Scientific and Technical Information of China (English)

    Xiaogang Chen; Hui Tian; Donglan Lai; Yan Tang; Honglan Jiang; Hualun Zeng; Yirui Li

    2007-01-01

    detection, rats in each group were daily drenched with Yizhining elixation once for 14 days successively. Rats in the Yizhining high-dose and low-dose groups were drenched with 12.6 mL/kg and 6.3 mL/kg Yizhining elixation (diluted to 25 mL/kg) respectively, and those in the blank control group were drenched with 12.5 mL/kg normal saline. On the 14th day after administration, the ratios of correct and immature response of rats were re-detected for 3 days successively by formal detection method for later analysis. The sustained attention of rats was evaluated with ratio of correct response: Ratio of correct response=[times of correct response/(times of correct response + times of incorrect response)]; impulsiveness was evaluated with the ratio of immature response: ratio of immature response=[times of immature response/ (times of correct response+times of incorrect response+times of omission+times of immature response) ].MAIN OUTCOME MEASURES: The effects of different doses of Yizhining elixation on the sustained attention (ratio of correct response) and impulsiveness (ratio of immature response) of spontaneous hypertensive rats.RESULTS: Thirty-six spontaneous hypertensive rats were involved in the final analysis. The ratio of correct response of rats in the Yizhining high dose and low dose groups after administration was (98.9 ± 2.30 )% and (96.6± 4.00) %, respectively, which was significantly higher than that before administration [ ( 80.4 ±11.5 ) %, (83.9±8.90) %, P< 0.01] and that in the blank control group[ (83.3±6.30) %, P < 0.01]. The ratio of immature response of rats in the Yizhining high dose and low dose groups after administration was (5.04 ± 1.04 ) %, (7.23 ± 1.22) %, respectively, which was lower than that before administration [ (9.85±2.50) %, (9.40±1.73 ) %, P < 0.05] and that in the blank control group [ (9.42 ± 1.64) %, P < 0.01 ].CONCLUSION: Yizhining elixation can improve the sustained attention and impulsiveness of spontaneous

  11. Improving creativity performance by short-term meditation

    Science.gov (United States)

    2014-01-01

    Background 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. Methods 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. Results 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). Conclusions Our results suggested that emotion-related creativity-promoting mechanism may be attributed to short-term meditation. PMID:24645871

  12. Compression Techniques for Improved Algorithm Computational Performance

    Science.gov (United States)

    Zalameda, Joseph N.; Howell, Patricia A.; Winfree, William P.

    2005-01-01

    Analysis of thermal data requires the processing of large amounts of temporal image data. The processing of the data for quantitative information can be time intensive especially out in the field where large areas are inspected resulting in numerous data sets. By applying a temporal compression technique, improved algorithm performance can be obtained. In this study, analysis techniques are applied to compressed and non-compressed thermal data. A comparison is made based on computational speed and defect signal to noise.

  13. Improving Fatigue Performance of AHSS Welds

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Zhili [ORNL; Yu, Xinghua [ORNL; ERDMAN III, DONALD L [ORNL; Wang, Yanli [ORNL; Kelly, Steve [ArcelorMittal USA; Hou, Wenkao [ArcelorMittal USA; Yan, Benda [ArcelorMittal USA; Wang, Zhifeng [Colorado School of Mines, Golden; Yu, Zhenzhen [Colorado School of Mines, Golden; Liu, Stephen [Colorado School of Mines, Golden

    2015-03-01

    Reported herein is technical progress on a U.S. Department of Energy CRADA project with industry cost-share aimed at developing the technical basis and demonstrate the viability of innovative in-situ weld residual stresses mitigation technology that can substantially improve the weld fatigue performance and durability of auto-body structures. The developed technology would be costeffective and practical in high-volume vehicle production environment. Enhancing weld fatigue performance would address a critical technology gap that impedes the widespread use of advanced high-strength steels (AHSS) and other lightweight materials for auto body structure light-weighting. This means that the automotive industry can take full advantage of the AHSS in strength, durability and crashworthiness without the concern of the relatively weak weld fatigue performance. The project comprises both technological innovations in weld residual stress mitigation and due-diligence residual stress measurement and fatigue performance evaluation. Two approaches were investigated. The first one was the use of low temperature phase transformation (LTPT) weld filler wire, and the second focused on novel thermo-mechanical stress management technique. Both technical approaches have resulted in considerable improvement in fatigue lives of welded joints made of high-strength steels. Synchrotron diffraction measurement confirmed the reduction of high tensile weld residual stresses by the two weld residual stress mitigation techniques.

  14. [Improved performance in endurance sports through acupuncture].

    Science.gov (United States)

    Benner, Stefan; Benner, K

    2010-09-01

    In many years of experience in treating athletes with acupuncture, I often had the impression that athletes in endurance sports showed improved performances after such treatments. In order to scientifically verify these impressions, I performed a field test with three groups of runners of different performance levels preparing for a marathon. The first group was given acupuncture, the second a placebo, with the third being the control group. After their maximum pulse rates were recorded, the runners were asked to run 5000m four times in 4 weeks at 75 % of their maximum pulse rate. Their pulse rates were measured for each runner at the finish of the run, and subsequently, one, two and five minutes after the run. Based on these data, the complexity factor (running time multiplied by the respective pulse rate) was calculated for all four recorded pulse rates for each run and each runner. All groups showed statistically significant enhancements in their running times and their complexity factors, but in the case of the runners treated with acupuncture, the improvements were highly significant. Therefore, the field test proves that acupuncture has a significant impact on the performance of the athletes in endurance sports.

  15. Improving Access to Foundational Energy Performance Data

    Energy Technology Data Exchange (ETDEWEB)

    Studer, D.; Livingood, W.; Torcellini, P.

    2014-08-01

    Access to foundational energy performance data is key to improving the efficiency of the built environment. However, stakeholders often lack access to what they perceive as credible energy performance data. Therefore, even if a stakeholder determines that a product would increase efficiency, they often have difficulty convincing their management to move forward. Even when credible data do exist, such data are not always sufficient to support detailed energy performance analyses, or the development of robust business cases. One reason for this is that the data parameters that are provided are generally based on the respective industry norms. Thus, for mature industries with extensive testing standards, the data made available are often quite detailed. But for emerging technologies, or for industries with less well-developed testing standards, available data are generally insufficient to support robust analysis. However, even for mature technologies, there is no guarantee that the data being supplied are the same data needed to accurately evaluate a product?s energy performance. To address these challenges, the U.S. Department of Energy funded development of a free, publically accessible Web-based portal, the Technology Performance Exchange(TM), to facilitate the transparent identification, storage, and sharing of foundational energy performance data. The Technology Performance Exchange identifies the intrinsic, technology-specific parameters necessary for a user to perform a credible energy analysis and includes a robust database to store these data. End users can leverage stored data to evaluate the site-specific performance of various technologies, support financial analyses with greater confidence, and make better informed procurement decisions.

  16. Performance Lapses in Children with Attention-Deficit/Hyperactivity Disorder Contribute to Poor Reading Fluency

    Science.gov (United States)

    Jacobson, Lisa A.; Ryan, Matthew; Denckla, Martha B.; Mostofsky, Stewart H.; Mahone, E. Mark

    2013-01-01

    Children with Attention-Deficit/Hyperactivity Disorder (ADHD) demonstrate increased response variability compared with controls, which is thought to be associated with deficits in attention regulation and response control that subsequently affect performance of more cognitively demanding tasks, such as reading. The present study examined response variability during a computerized simple reaction time (RT) task in 67 children. Ex-Gaussian analyses separated the response time distribution into normal (mu and sigma) and exponential (tau) components; the association of each with reading fluency was examined. Children with ADHD had significantly slower, more variable, and more skewed RTs compared with controls. After controlling for ADHD symptom severity, tau (but not mu or mean RT) was significantly associated with reduced reading fluency, but not with single word reading accuracy. These data support the growing evidence that RT variability, but not simply slower mean response speed, is the characteristic of youth with ADHD and that longer response time latencies (tau) may be implicated in the poorer academic performance associated with ADHD. PMID:23838684

  17. Improving Contract Performance by Corrective Actions Plans

    Energy Technology Data Exchange (ETDEWEB)

    Dowd, A.S., jr.

    2002-06-23

    Corrective Action Plans (CAPs) are required to be developed, submitted, and reported upon by the prime contractors for the U.S. Department of Energy (U.S. DOE) Management and Operations (M and O) contracts. The best known CAP ''type,'' and there are many, is for Price-Anderson Amendments Act (PAAA) ''potential noncompliances.'' The M and O contractor fines for PAAA problems have increased from approximately $100,000 in 1996 to almost $2,000,000 in 2000. In order to improve CAP performance at the National Nuclear Security Administration (NNSA) site at Y-12 in Oak Ridge, Tennessee, the contractor chose to centralize the company-wide processes of problem identification and reporting with the PAAA (and other) CAP processes. This directly integrates these functional reports to the contractor General Manager. The functions contained in the M and O contractor central organization, called ''Performance Assurance,'' are: PAAA; Defense Nuclear Facilities Safety Board (DNFSB) Liaison; Contract Requirements Management; Issues Management (including the CAP processes); Lessons Learned; Independent and Management Assessments; Internal Audits; and Ethics. By centrally locating and managing these problem identification and problem correction functions, the contractor, BWXT Y-12, L.L.C., has improved PAAA (and other) CAP performance more than 200 percent in the first year of the contract. Much of this improvement (see Table 1 for examples) has been achieved by increasing the knowledge and experience of management and workers in the specific contract and company requirements for CAPs. The remainder of this paper will describe some of the many CAP processes at Y-12 to show the reader the non-trivial scope of the CAP process. Improvements in CAP management will be discussed. In addition, a specific recommendation for CAP management, in a major capital construction project, will be presented.

  18. The Effect of Chronic Alprazolam Intake on Memory, Attention, and Psychomotor Performance in Healthy Human Male Volunteers

    Directory of Open Access Journals (Sweden)

    Zahid Sadek Chowdhury

    2016-01-01

    Full Text Available Alprazolam is used as an anxiolytic drug for generalized anxiety disorder and it has been reported to produce sedation and anterograde amnesia. In the current study, we randomly divided 26 healthy male volunteers into two groups: one group taking alprazolam 0.5 mg and the other taking placebo daily for two weeks. We utilized the Cambridge Neuropsychological Test Automated Battery (CANTAB software to assess the chronic effect of alprazolam. We selected Paired Associates Learning (PAL and Delayed Matching to Sample (DMS tests for memory, Rapid Visual Information Processing (RVP for attention, and Choice Reaction Time (CRT for psychomotor performance twice: before starting the treatment and after the completion of the treatment. We found statistically significant impairment of visual memory in one parameter of PAL and three parameters of DMS in alprazolam group. The PAL mean trial to success and total correct matching in 0-second delay, 4-second delay, and all delay situation of DMS were impaired in alprazolam group. RVP total hits after two weeks of alprazolam treatment were improved in alprazolam group. But such differences were not observed in placebo group. In our study, we found that chronic administration of alprazolam affects memory but attentive and psychomotor performance remained unaffected.

  19. A conceptual model for manufacturing performance improvement

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    M.A. Karim

    2009-07-01

    Full Text Available Purpose: Important performance objectives manufacturers sought can be achieved through adopting the appropriate manufacturing practices. This paper presents a conceptual model proposing relationship between advanced quality practices, perceived manufacturing difficulties and manufacturing performances.Design/methodology/approach: A survey-based approach was adopted to test the hypotheses proposed in this study. The selection of research instruments for inclusion in this survey was based on literature review, the pilot case studies and relevant industrial experience of the author. A sample of 1000 manufacturers across Australia was randomly selected. Quality managers were requested to complete the questionnaire, as the task of dealing with the quality and reliability issues is a quality manager’s major responsibility.Findings: Evidence indicates that product quality and reliability is the main competitive factor for manufacturers. Design and manufacturing capability and on time delivery came second. Price is considered as the least important factor for the Australian manufacturers. Results show that collectively the advanced quality practices proposed in this study neutralize the difficulties manufacturers face and contribute to the most performance objectives of the manufacturers. The companies who have put more emphasize on the advanced quality practices have less problem in manufacturing and better performance in most manufacturing performance indices. The results validate the proposed conceptual model and lend credence to hypothesis that proposed relationship between quality practices, manufacturing difficulties and manufacturing performances.Practical implications: The model shown in this paper provides a simple yet highly effective approach to achieving significant improvements in product quality and manufacturing performance. This study introduces a relationship based ‘proactive’ quality management approach and provides great

  20. Improving Vaginal Examinations Performed by Midwives

    Directory of Open Access Journals (Sweden)

    Rhoda S. Muliira

    2013-06-01

    Full Text Available A vaginal examination (VE is an essential part of midwifery care, and is routinely performed when assessing the progress of labour. As evidence shows that during labour women may find VEs unpleasant,embarrassing and sometimes painful, the aim of this article is to review literature on the use of VEs during labour and to synthesise information from the available literature on how to provide an effective VE. The studies considered were retrieved from three databases (the Cumulative Index to Nursing and Allied Health Literature [CINAHL], SCOPUS and MEDLINE using the following search terms: “VEs in labour”, “midwives and use of VEs” and “women experiences of VEs in labour”. The literature reviewed suggests that midwives are not careful about VEs. Therefore, a concerted effort is needed to pay attention to the frequency of VEs, the management ofpain and distress, information-giving and the preferences of the patient, so that the patient can feel in control during a VE.

  1. Nicotine increases impulsivity and decreases willingness to exert cognitive effort despite improving attention in "slacker" rats: insights into cholinergic regulation of cost/benefit decision making.

    Directory of Open Access Journals (Sweden)

    Jay G Hosking

    Full Text Available Successful decision making in our daily lives requires weighing an option's costs against its associated benefits. The neuromodulator acetylcholine underlies both the etiology and treatment of a number of illnesses in which decision making is perturbed, including Alzheimer's disease, attention-deficit/hyperactivity disorder, and schizophrenia. Nicotine acts on the cholinergic system and has been touted as a cognitive enhancer by both smokers and some researchers for its attention-boosting effects; however, it is unclear whether treatments that have a beneficial effect on attention would also have a beneficial effect on decision making. Here we utilize the rodent Cognitive Effort Task (rCET, wherein animals can choose to allocate greater visuospatial attention for a greater reward, to examine cholinergic contributions to both attentional performance and choice based on attentional demand. Following the establishment of baseline behavior, four drug challenges were administered: nicotine, mecamylamine, scopolamine, and oxotremorine (saline plus three doses for each. As per previous rCET studies, animals were divided by their baseline preferences, with "worker" rats choosing high-effort/high-reward options more than their "slacker" counterparts. Nicotine caused slackers to choose even fewer high-effort trials than at baseline, but had no effect on workers' choice. Despite slackers' decreased willingness to expend effort, nicotine improved their attentional performance on the task. Nicotine also increased measures of motor impulsivity in all animals. In contrast, scopolamine decreased animals' choice of high-effort trials, especially for workers, while oxotremorine decreased motor impulsivity for all animals. In sum, the cholinergic system appears to contribute to decision making, and in part these contributions can be understood as a function of individual differences. While nicotine has been considered as a cognitive enhancer, these data suggest

  2. Acute nicotine administration effects on fractional anisotropy of cerebral white matter and associated attention performance

    Directory of Open Access Journals (Sweden)

    Peter eKochunov

    2013-09-01

    Full Text Available Introduction.Nicotinic acetylcholine receptors are present in the cerebral white matter (WM. We hypothesized that WM response to nicotine can be detected by diffusion tensor imaging (DTI; and that such responses may be associated with nicotine-led cognitive enhancement in sustained attention. MethodsA randomized, nicotine-placebo patch, crossover, double-blind clinical trial in two non-overlapping cohorts of smokers was used to test the hypothesis. The discovery cohort consisted of 39 subjects (N=20/19 controls/schizophrenic patients, age=36.8±10.1years and the replication cohorts consisted of 38 healthy smokers (31.7±10.5years. WM integrity was measured by fractional anisotropy (FA values for the whole brain and nine preselected WM tracts using tract-based-spatial-statistics. Results.Nicotine significantly enhanced FA values for the genu of corpus callosum compared with placebo (FAgenu (p=0.01 in smokers with low recent smoking exposure as measured by low average cotinine level. This finding was replicated in the second cohort (p=0.02. FAgenu values explained 22% of variance in performance of a sustained attention task during the nicotine session (p=0.006. However, this effect was limited to schizophrenia patients (r= 0.62 and 0.09; p=0.003 and 0.7 for patients and controls, respectively.Conclusion. Acute pharmacological influence of nicotine patch on WM integrity appeared present, but was dependent on nicotine intake from recent smoking. Change in the WM integrity in the genu of corpus callosum was assocatied with a significant proportion of variability of nicotine-led changes in sustained attention/working memory of the smokers. Further studies will be necessary to understand biophysical underpinning of the nicotine-related changes in FA.

  3. Real-time performance modelling of a Sustained Attention to Response Task.

    Science.gov (United States)

    Larue, Grégoire S; Rakotonirainy, Andry; Pettitt, Anthony N

    2010-10-01

    Vigilance declines when exposed to highly predictable and uneventful tasks. Monotonous tasks provide little cognitive and motor stimulation and contribute to human errors. This paper aims to model and detect vigilance decline in real time through participants' reaction times during a monotonous task. A laboratory-based experiment adapting the Sustained Attention to Response Task (SART) is conducted to quantify the effect of monotony on overall performance. Relevant parameters are then used to build a model detecting hypovigilance throughout the experiment. The accuracy of different mathematical models is compared to detect in real time - minute by minute - the lapses in vigilance during the task. It is shown that monotonous tasks can lead to an average decline in performance of 45%. Furthermore, vigilance modelling enables the detection of vigilance decline through reaction times with an accuracy of 72% and a 29% false alarm rate. Bayesian models are identified as a better model to detect lapses in vigilance as compared with neural networks and generalised linear mixed models. This modelling could be used as a framework to detect vigilance decline of any human performing monotonous tasks. STATEMENT OF RELEVANCE: Existing research on monotony is largely entangled with endogenous factors such as sleep deprivation, fatigue and circadian rhythm. This paper uses a Bayesian model to assess the effects of a monotonous task on vigilance in real time. It is shown that the negative effects of monotony on the ability to sustain attention can be mathematically modelled and predicted in real time using surrogate measures, such as reaction times. This allows the modelling of vigilance fluctuations.

  4. Impact of acute aerobic exercise and cardiorespiratory fitness on visuospatial attention performance and serum BDNF levels.

    Science.gov (United States)

    Tsai, Chia-Liang; Chen, Fu-Chen; Pan, Chien-Yu; Wang, Chun-Hao; Huang, Tsang-Hai; Chen, Tzu-Chi

    2014-03-01

    The purpose of the current study was to explore various behavioral and neuroelectric indices after acute aerobic exercise in young adults with different cardiorespiratory fitness levels when performing a cognitive task, and also to gain a mechanistic understanding of the effects of such exercise using the brain-derived neurotrophic factor (BDNF) biochemical index. Sixty young adults were separated into one non-exercise-intervention and two exercise intervention (EI) (i.e., EIH: higher-fit and EIL: lower-fit) groups according to their maximal oxygen consumption. The participants' cognitive performances (i.e., behavioral and neuroelectric indices via an endogenous visuospatial attention task test) and serum BDNF levels were measured at baseline and after either an acute bout of 30min of moderate intensity aerobic exercise or a control period. Analyses of the results revealed that although acute aerobic exercise decreased reaction times (RTs) and increased the central Contingent Negative Variation (CNV) area in both EI groups, only the EIH group showed larger P3 amplitude and increased frontal CNV area after acute exercise. Elevated BDNF levels were shown after acute exercise for both EI groups, but this was not significantly correlated with changes in behavioral and neuroelectric performances for either group. These results suggest that both EI groups could gain response-related (i.e., RT and central CNV) benefits following a bout of moderate acute aerobic exercise. However, only higher-fit individuals could obtain particular cognition-process-related efficiency with regard to attentional resource allocation (i.e., P3 amplitude) and cognitive preparation processes (i.e., frontal CNV) after acute exercise, implying that the mechanisms underlying the effects of such exercise on neural functioning may be fitness dependent. However, the facilitating effects found in this work could not be attributed to the transient change in BDNF levels after acute exercise.

  5. Disease management as a performance improvement strategy.

    Science.gov (United States)

    McClatchey, S

    2001-11-01

    Disease management is a strategy of organizing care and services for a patient population across the continuum. It is characterized by a population database, interdisciplinary and interagency collaboration, and evidence-based clinical information. The effectiveness of a disease management program has been measured by a combination of clinical, financial, and quality of life outcomes. In early 1997, driven by a strategic planning process that established three Centers of Excellence (COE), we implemented disease management as the foundation for a new approach to performance improvement utilizing five key strategies. The five implementation strategies are outlined, in addition to a review of the key elements in outcome achievement.

  6. Improving construction performance through supply chain management

    Institute of Scientific and Technical Information of China (English)

    王要武; 薛小龙

    2004-01-01

    A typical model of construction supply chain (CSC) is presented firstly. Then the characteristics and problems of CSC are identified. The authors also describe the progress towards adoption of supply chain management (SCM) in the construction industry. Traditional construction management approaches (CMAs) are compared with new SCM-based CMAs. The authors suggest that integrated SCM based on cooperating competition is crucial to improve construction performance. Based on relevant results from related research, a framework for integrated construction supply chain management (CSCM) is developed to guide the effective implementation of SCM in construction.

  7. Improved Operating Performance of Mining Machine Picks

    Science.gov (United States)

    Prokopenko, S.; Li, A.; Kurzina, I.; Sushko, A.

    2016-08-01

    The reasons of low performance of mining machine picks are stated herein. In order to improve the wear resistance and the cutting ability of picks a new design of a cutting carbide tip insert to be fixed on a removable and rotating pick head is developed. Owing to the new design, the tool ensures a twofold increase in the cutting force maintained longer, a twofold reduction in the specific power consumption of the breaking process, and extended service life of picks and the possibility of their multiple use.

  8. Performance of juvenile baboons on neuropsychological tests assessing associative learning, motivation and attention.

    Science.gov (United States)

    Zürcher, Nicole R; Rodriguez, Jesse S; Jenkins, Sue L; Keenan, Kate; Bartlett, Thad Q; McDonald, Thomas J; Nathanielsz, Peter W; Nijland, Mark J

    2010-05-15

    The CANTAB (Cambridge Neuropsychological Test Automated Battery), a system developed for human neuropsychological testing, has previously been used to assess cognitive function in two species of nonhuman primates, common marmoset monkeys and rhesus macaques. We describe the application of the system to the juvenile baboon, a nonhuman primate species offering specific investigative advantages. Juvenile baboons were trained and tested on a progressive ratio task to assess motivation, simple discrimination and simple reversal tasks to assess associative learning, and intra- and extra-dimensional set-shifting tasks to assess selective attention and attentional set-shifting, respectively. Study subjects were 8 juvenile baboons (Papio sp.), 4 females and 4 males aged 3.0+/-0.1 (mean+SEM) years and weight 8.2+/-0.4 kg. All baboons were easily trained, readily learned the neuropsychological tests and exhibited a stable performance. Applying a method such as the CANTAB has significant implications for expanding on the translational utility of the baboon in studies of neurodevelopment.

  9. Improvement of Automotive Part Supplier Performance Evaluation

    Science.gov (United States)

    Kongmunee, Chalermkwan; Chutima, Parames

    2016-05-01

    This research investigates the problem of the part supplier performance evaluation in a major Japanese automotive plant in Thailand. Its current evaluation scheme is based on experiences and self-opinion of the evaluators. As a result, many poor performance suppliers are still considered as good suppliers and allow to supply parts to the plant without further improvement obligation. To alleviate this problem, the brainstorming session among stakeholders and evaluators are formally conducted. The result of which is the appropriate evaluation criteria and sub-criteria. The analytical hierarchy process is also used to find suitable weights for each criteria and sub-criteria. The results show that a newly developed evaluation method is significantly better than the previous one in segregating between good and poor suppliers.

  10. Mind-wandering, cognition, and performance: a theory-driven meta-analysis of attention regulation.

    Science.gov (United States)

    Randall, Jason G; Oswald, Frederick L; Beier, Margaret E

    2014-11-01

    The current meta-analysis accumulates empirical findings on the phenomenon of mind-wandering, integrating and interpreting findings in light of psychological theories of cognitive resource allocation. Cognitive resource theory emphasizes both individual differences in attentional resources and task demands together to predict variance in task performance. This theory motivated our conceptual and meta-analysis framework by introducing moderators indicative of task-demand to predict who is more likely to mind-wander under what conditions, and to predict when mind-wandering and task-related thought are more (or less) predictive of task performance. Predictions were tested via a random-effects meta-analysis of correlations obtained from normal adult samples (k = 88) based on measurement of specified episodes of off-task and/or on-task thought frequency and task performance. Results demonstrated that people with fewer cognitive resources tend to engage in more mind-wandering, whereas those with more cognitive resources are more likely to engage in task-related thought. Addressing predictions of resource theory, we found that greater time-on-task-although not greater task complexity-tended to strengthen the negative relation between cognitive resources and mind-wandering. Additionally, increases in mind-wandering were generally associated with decreases in task performance, whereas increases in task-related thought were associated with increased performance. Further supporting resource theory, the negative relation between mind-wandering and performance was more pronounced for more complex tasks, though not longer tasks. Complementarily, the positive association between task-related thought and performance was stronger for more complex tasks and for longer tasks. We conclude by discussing implications and future research directions for mind-wandering as a construct of interest in psychological research.

  11. Effects of state anxiety on performance using a task-switching paradigm: an investigation of attentional control theory.

    Science.gov (United States)

    Derakshan, Nazanin; Smyth, Sinéad; Eysenck, Michael W

    2009-12-01

    Low- and high-anxious participants performed arithmetical tasks under task-switching or nontask-switching conditions. These tasks were low or high in complexity. The task on each trial was either explicitly cued or not cued. We assumed that demands on attentional control would be greater in the task-switching condition than in the nontask-switching condition, and would be greater with high-complexity tasks than with low-complexity ones. We also assumed that demands on attentional control would be greater when cues were absent rather than present. According to attentional control theory (Eysenck, Derakshan, Santos, & Calvo, 2007), anxiety impairs attentional control processes required to shift attention optimally within and between tasks. We predicted that there would be greater negative effects of high state anxiety in the task-switching condition than in the nontask-switching condition. Our theoretical predictions were supported, suggesting that state anxiety reduces attentional control.

  12. Performance patterns in Conners' CPT among children with attention deficit hyperactivity disorder and dyslexia

    Directory of Open Access Journals (Sweden)

    Monica Carolina Miranda

    2012-02-01

    Full Text Available This study investigated the performance of children with attention deficit hyperactivity disorder (ADHD and dyslexia using Conners' Continuous Performance Test (CCPT. The clinical groups were composed of 52 children with ADHD and 32 children with dyslexia. Performance in the CCPT was evaluated using ANCOVA to compare the clinical groups with the normative Brazilian sample. The ADHD group performed worse than the normative sample in almost all of the measurements, except for reaction time and response style. The dyslexia group scored higher on commissions, variability, perseverations and inconsistency in the reaction time over the six time blocks (Hit SE Block Change than the children in the normative Brazilian sample. The ADHD and dyslexia groups differed in omission measurements, Hit RT SE, variability, perseverations, Hit RT Interstimulus Intervals (ISI Change and Hit SE ISI Change. We thus found that the dyslexia group had specific deficit patterns, with greater response to non-target stimuli, greater perseveration and response variability, and difficulties in hit reaction time as the test progressed.

  13. Attentional inhibition in bilingual naming performance: Evidence from delta-plot analyses

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    Ardi eRoelofs

    2011-08-01

    Full Text Available It has been argued that inhibition is a mechanism of attentional control in bilingual language performance. Evidence suggests that effects of inhibition are largest in the tail of a response time (RT distribution in non-linguistic and monolingual performance domains. We examined this for bilingual performance by conducting delta-plot analyses of naming RTs. Dutch-English bilingual speakers named pictures using English while trying to ignore superimposed neutral Xs or Dutch distractor words that were semantically related, unrelated, or translations. The mean RTs revealed semantic, translation, and lexicality effects. The delta plots leveled off with increasing RT, more so when the mean distractor effect was smaller as compared with larger. This suggests that the influence of inhibition is largest towards the distribution tail, corresponding to what is observed in other performance domains. Moreover, the delta plots suggested that more inhibition was applied by high- than low-proficiency individuals in the unrelated than the other distractor conditions. These results support the view that inhibition is a domain-general mechanism that may be optionally engaged depending on the prevailing circumstances.

  14. Performance of gymnastics skill benefits from an external focus of attention.

    Science.gov (United States)

    Abdollahipour, Reza; Wulf, Gabriele; Psotta, Rudolf; Palomo Nieto, Miriam

    2015-01-01

    The present study was designed to fill a gap in the literature on attentional focus and sports performance. Specifically, in contrast to most previous studies in which an external focus was directed at an implement, we used a gymnastics skill that did not involve the use of an implement. Furthermore, while most studies used only outcome measures of performance, we also assessed movement quality. Twelve-year-old gymnasts performed a maximum vertical jump with a 180-degree turn while airborne, with their hands crossing in front of their chest during the turn under three different focus conditions. Under the external focus condition, participants were asked to focus on the direction in which a tape marker, which was attached to their chest, was pointing after the turn. Under the internal focus condition, they were asked to focus on the direction in which their hands were pointing after the turn. Under the control condition, no focus instructions were given. The external focus condition resulted in both superior movement form and greater jump height than did the other two conditions, which produced comparable results. The present findings show that, similar to other tasks, the performance of form-based skills can be enhanced relatively easily by appropriate external focus instructions.

  15. Measurement of mental attention: Assessing a cognitive component underlying performance on standardized intelligence tests

    Directory of Open Access Journals (Sweden)

    Steven J. Howard

    2013-09-01

    Full Text Available Despite the widespread use of standardized IQ tests to measure human intelligence, problems with such measures have led some to suggest that better indices may derive from measurement of cognitive processes underlying performance on IQ tests (e.g., working memory capacity. However, measures from both approaches may exhibit performance biases in favour of majority groups, due to the influence of prior learning and experience. Mental attentional (M- capacity is proposed to be a causal factor underlying developmental growth in working memory. Measures of M-capacity index important cognitive variance underlying performance on standardized intelligence tests. These measures appear to be reasonably culture-fair and invariant across content domains. The current study tested theoretical predictions regarding the content-invariance of M-measures and the development of M-capacity for groups of children differing in performance on standardized IQ tests. Ninety-one participants differentiated on the basis of academic stream (intellectually gifted vs. mainstream and age (grade 4 vs. grade 8 received measures of M-capacity in the verbal and visuo-spatial domains. Children identified as gifted scored about one stage higher on both measures. Results suggest that measures of M-capacity may be useful adjuncts to standardized intelligence measures.

  16. Virtual environment to quantify the influence of colour stimuli on the performance of tasks requiring attention

    Directory of Open Access Journals (Sweden)

    Frère Annie F

    2011-08-01

    where tasks, that require attention, were most affected. Conclusions The game proved to be a user-friendly tool capable to detect and quantify the influence of color on the performance of people executing tasks that require attention and showed to be attractive for people with ADHD.

  17. Acute personalized habitual caffeine doses improve attention and have selective effects when considering the fractionation of executive functions.

    Science.gov (United States)

    Lanini, Juliana; Galduróz, José Carlos Fernandes; Pompéia, Sabine

    2016-01-01

    Caffeine is widely used, often consumed with food, and improves simple and complex/executive attention under fasting conditions. We investigated whether these cognitive effects are observed when personalized habitual doses of caffeine are ingested by caffeine consumers, whether they are influenced by nutriments and if various executive domains are susceptible to improvement. This was a double-blind, placebo-controlled study including 60 young, healthy, rested males randomly assigned to one of four treatments: placebo fasting, caffeine fasting, placebo meal and caffeine meal. Caffeine doses were individualized for each participant based on their self-reported caffeine consumption at the time of testing (morning). The test battery included measures of simple and sustained attention, executive domains (inhibiting, updating, shifting, dual tasking, planning and accessing long-term memory), control measures of subjective alterations, glucose and insulin levels, skin conductance, heart rate and pupil dilation. Regardless of meal intake, acute habitual doses of caffeine decreased fatigue, and improved simple and sustained attention and executive updating. This executive effect was not secondary to the habitual weekly dose consumed, changes in simple and sustained attention, mood, meal ingestion and increases in cognitive effort. We conclude that the morning caffeine "fix" has positive attentional effects and selectively improved executive updating whether or not caffeine is consumed with food.

  18. The alpha-2A adrenoceptor agonist guanfacine improves sustained attention and reduces overactivity and impulsiveness in an animal model of Attention-Deficit/Hyperactivity Disorder (ADHD

    Directory of Open Access Journals (Sweden)

    Sagvolden Terje

    2006-12-01

    Full Text Available Abstract Background ADHD is currently defined as a cognitive/behavioral developmental disorder where all clinical criteria are behavioral. Overactivity, impulsiveness, and inattentiveness are presently regarded as the main clinical symptoms. There is no biological marker, but there is considerable evidence to suggest that ADHD behavior is associated with poor dopaminergic and noradrenergic modulation of neuronal circuits that involve the frontal lobes. The best validated animal model of ADHD, the Spontaneously Hypertensive Rat (SHR, shows pronounced overactivity, impulsiveness, and deficient sustained attention. While dopamine release is decreased in SHR prefrontal cortex, norepinephrine concentrations are elevated. The noradrenergic system appears to be hyperactive as a result of impaired alpha-2A adrenoceptor regulation. Thus, the present study tested behavioral effects of the centrally acting alpha-2A adrenoceptor agonist guanfacine on SHR behavior. Methods The present study tested behavioral effects of guanfacine at doses of 0.075, 0.15, 0.30 and 0.60 mg base/kg i.p. in both male SHRs and their controls, the Wistar Kyoto rat (WKY. ADHD-like behavior was tested with a visual discrimination task measuring overactivity, impulsiveness and inattentiveness. Results The striking impulsiveness, overactivity, and reduced sustained attention during baseline conditions in the SHR improved by treatment with guanfacine. The most pronounced improvement in SHR behavior was seen following the two highest doses (0.3 and 0.6 mg/kg of guanfacine when SHR behaviors virtually normalized. The positive effects of the drug were most marked towards the end of the session. Conclusion The results indicate that guanfacine improved poor noradrenergic modulation of neuronal circuits that involve the frontal lobes in an animal model of ADHD. The present results support the beneficial effects of guanfacine on ADHD behavior reported clinically and experimentally in primate

  19. Improving human performance: Industry factors influencing the ability to perform

    Directory of Open Access Journals (Sweden)

    Güera Massyn Romo

    2013-03-01

    Full Text Available Learning interventions and new technologies that aim to improve human performance must take cognisance of industry factors inhibiting human performance. The dynamic and fast pace nature of the Information and Communication Technologies (ICT and the engineering industries do not lend themselves to proper skills planning and management. These industries experience real skills gaps, to some of which they contribute by themselves. This study reports on these performance-inhibiting factors such as the underutilisation of available skills, tolerance for individual preferences, and dynamically, and informally refining a role objective while an employee is occupying a certain role. The important professional skills required by individuals to cope with these real life factors are also explored in the skills gaps management context. Moreover, these industries need a profile they refer to as Special Forces, which denotes a high calibre of worker that possesses well-developed professional skills whilst having advanced technical expertise and sufficient experience. This resource profile is required largely due to the poor management of human resource processes in practice and the current reported lack of adequate skills. Furthermore, this study refers to the recent lack of a working definition for these Special Forces leading to the omitted active development of these profiles in industry today, which appears to become a key human performance inhibiting factor.

  20. Parental perceptions of academic performance and attainment of children diagnosed with attention deficit hyperactivity disorder.

    Science.gov (United States)

    Barnard-Brak, Lucy; Schmidt, Marcelo; Wei, Tianlan; Parker, Sonia L; Attai, Shanna L

    2013-07-01

    We examined parental perceptions of academic performance and attainment of children with attention deficit hyperactivity disorder (ADHD) according to both parent and child gender along with the interaction of parent and child gender. The current study adds to the body of research by examining the perceptions of parents of children with ADHD according to both parent and child gender. The results indicate that fathers, on the whole, seemed less likely to consider ADHD to have negative academic implications for their children as compared with mothers. With regard to child gender, the fathers seemed less likely to consider ADHD to have negative academic implications for their sons over their daughters. The results suggest that interventions for parents of children with ADHD should be targeted to fathers with sons with ADHD.

  1. Will working memory training generalize to improve off-task behavior in children with attention-deficit/hyperactivity disorder?

    Science.gov (United States)

    Green, Chloe T; Long, Debra L; Green, David; Iosif, Ana-Maria; Dixon, J Faye; Miller, Meghan R; Fassbender, Catherine; Schweitzer, Julie B

    2012-07-01

    Computerized working memory and executive function training programs designed to target specific impairments in executive functioning are becoming increasingly available, yet how well these programs generalize to improve functional deficits in disorders, such as attention-deficit/hyperactivity disorder (ADHD), beyond the training context is not well-established. The aim of this study was to examine the extent to which working memory (WM) training in children with ADHD would diminish a core dysfunctional behavior associated with the disorder, "off-task" behavior during academic task performance. The effect of computerized WM training (adaptive) was compared to a placebo condition (nonadaptive) in a randomized, double-blind, placebo-controlled design in 26 children (18 males; age, 7 to 14 years old) diagnosed with ADHD. Participants completed the training in approximately 25 sessions. The Restricted Academic Situations Task (RAST) observational system was used to assess aspects of off-task behavior during the completion of an academic task. Traditional measures of ADHD symptoms (Conners' Parent Rating Scale) and WM ability (standardized WM tests) were also collected. WM training led to significant reductions in off-task ADHD-associated behavior on the RAST system and improvement on WM tests. There were no significant differences between groups in improvement on parent rating scales. Findings lend insight into the generalizability of the effects of WM training and the relation between deficits in WM and off-task behavioral components of ADHD. These preliminary data suggest WM training may provide a mechanism for indirectly altering academic performance in children with ADHD.

  2. Environmental enrichment improves cognitive deficits in Spontaneously Hypertensive Rats (SHR): relevance for Attention Deficit/Hyperactivity Disorder (ADHD).

    Science.gov (United States)

    Pamplona, Fabrício A; Pandolfo, Pablo; Savoldi, Robson; Prediger, Rui Daniel S; Takahashi, Reinaldo N

    2009-10-01

    The interaction between genes and environment seems to be relevant for the development of Attention Deficit/Hyperactivity Disorder (ADHD), one of the most prevalent childhood psychiatric diseases. The occurrence of ADHD is typically associated with poor academic performance, probably reflecting learning difficulties and/or cognitive impulsiveness. The inbred Spontaneously Hypertensive Rats (SHR) strain has often been considered as an animal model of ADHD, since they 'naturally' display the main ADHD symptomatology. Although pharmacological agents improve SHR's cognitive deficits, little is known about the involvement of environmental factors in SHR disabilities and to what extent 'protective' non-pharmacological factors may be considered as strategy for ADHD prevention. Here we investigated whether the rearing environment during neurodevelopment may counteract later cognitive deficits presented by adult SHR. Wistar (WIS) rats were also used to investigate whether the putative effects of environmental enrichment depend on a specific genetic background. The animals were reared in enriched environment (EE) or standard environment (SE) from the post-natal day 21 until 3 months of age (adulthood) and tested for cognitive and non-cognitive phenotypes. EE improved SHR's performance in open field habituation, water maze spatial reference, social and object recognition tasks, while non-cognitive traits, such as nociception and hypertension, were not affected by EE. Response of WIS rats was generally not affected by the present EE. These results show that the general low cognitive performance presented by SHR rats strongly depends on the rearing environment and they may suggest modifications of the familial environment as a putative preventive strategy to cope with ADHD.

  3. Examining Vision and Attention in Sports Performance Using a Gaze-Contingent Paradigm

    Directory of Open Access Journals (Sweden)

    Donghyun Ryu

    2012-10-01

    Full Text Available In time-constrained activities, such as competitive sports, the rapid acquisition and comprehension of visual information is vital for successful performance. Currently our understanding of how and what visual information is acquired and how this changes with skill development is quite rudimentary. Interpretation of eye movement behaviour is limited by uncertainties surrounding the relationship between attention, line-of-gaze data, and the mechanism of information pick-up from different sectors of the visual field. We used gaze-contingent display methodology to provide a selective information presentation to the central and peripheral parts of the visual field while performing a decision-making task. Eleven skilled and 11 less-skilled players watched videos of basketball scenarios under three different vision conditions (tunnel, masked, and full vision and in a forced-choice paradigm responded whether it was more appropriate for the ball carrier to pass or drive. In the tunnel and mask conditions vision was selectively restricted to, or occluded from, 5o around the line of gaze respectively. The skilled players showed significantly higher response accuracy and faster response times compared to their lesser skilled counterparts irrespective of the vision condition, demonstrating the skilled players' superiority in information extraction irrespective of the segment of visual field they rely on. Findings suggest that the capability to interpret visual information appears to be the key limiting factor to expert performance rather than the sector of the visual field in which the information is detected.

  4. GPU Computing to Improve Game Engine Performance

    Directory of Open Access Journals (Sweden)

    Abu Asaduzzaman

    2014-07-01

    Full Text Available Although the graphics processing unit (GPU was originally designed to accelerate the image creation for output to display, today’s general purpose GPU (GPGPU computing offers unprecedented performance by offloading computing-intensive portions of the application to the GPGPU, while running the remainder of the code on the central processing unit (CPU. The highly parallel structure of a many core GPGPU can process large blocks of data faster using multithreaded concurrent processing. A game engine has many “components” and multithreading can be used to implement their parallelism. However, effective implementation of multithreading in a multicore processor has challenges, such as data and task parallelism. In this paper, we investigate the impact of using a GPGPU with a CPU to design high-performance game engines. First, we implement a separable convolution filter (heavily used in image processing with the GPGPU. Then, we implement a multiobject interactive game console in an eight-core workstation using a multithreaded asynchronous model (MAM, a multithreaded synchronous model (MSM, and an MSM with data parallelism (MSMDP. According to the experimental results, speedup of about 61x and 5x is achieved due to GPGPU and MSMDP implementation, respectively. Therefore, GPGPU-assisted parallel computing has the potential to improve multithreaded game engine performance.

  5. Clinical symptoms and performance on the continuous performance test in children with attention deficit hyperactivity disorder between subtypes: a natural follow-up study for 6 months

    Directory of Open Access Journals (Sweden)

    Chiang Yuan-Lin

    2011-04-01

    Full Text Available Abstract Background The aims of this study were to determine the time course of improvements in attention deficit hyperactivity disorder (ADHD clinical symptoms and neurocognitive function in a realistic clinical setting, and the differences in ADHD symptom improvement using different classifications of ADHD subtypes. Methods The Child Behavior Checklist (CBCL was completed by parents of ADHD children at the initial visit. The computerized Continuous Performance Test (CPT, Swanson, Nolan, and Pelham, and Version IV Scale for ADHD (SNAP-IV, and ADHD Rating Scale (ADHD-RS were performed at baseline, one month, three months, and six months later, respectively. Patient care including drug therapy was performed at the discretion of the psychiatrist. The ADHD patients were divided into DSM-IV subtypes (Inattentive, Hyperactive-impulsive and Combined type, and were additionally categorized into aggressive and non-aggressive subtypes by aggression scale in CBCL for comparisons. Results There were 50 ADHD patients with a mean age of 7.84 ± 1.64 years; 15 of them were inattentive type, 11 were hyperactive-impulsive type, and 24 were combined type. In addition, 28 of the ADHD patients were grouped into aggressive and 22 into non-aggressive subtypes. There were significant improvements in clinical symptoms of hyperactivity and inattention, and impulsivity performance in CPT during the 6-month treatment. The clinical hyperactive symptoms were significantly different between ADHD patients sub-grouping both by DSM-IV and aggression. Non-aggressive patients had significantly greater changes in distraction and impulsivity performances in CPT from baseline to month 6 than aggressive patients. Conclusions We found that ADHD symptoms, which included impulsive performances in CPT and clinical inattention and hyperactivity dimensions, had improved significantly over 6 months under pragmatic treatments. The non-aggressive ADHD patients might have a higher potential

  6. Attentional and visual demands for sprint performance in non-fatigued and fatigued conditions : reliability of a repeated sprint test

    NARCIS (Netherlands)

    Reininga, Inge H. F.; Lemmink, Koen A. P. M.; Diercks, Ron L.; Buizer, Arina T.; Stevens, Martin

    2010-01-01

    Background: Physical performance measures are widely used to assess physical function, providing information about physiological and biomechanical aspects of motor performance. However they do not provide insight into the attentional and visual demands for motor performance. A figure-of-eight sprint

  7. MEMS Actuators for Improved Performance and Durability

    Science.gov (United States)

    Yearsley, James M.

    Micro-ElectroMechanical Systems (MEMS) devices take advantage of force-scaling at length scales smaller than a millimeter to sense and interact with directly with phenomena and targets at the microscale. MEMS sensors found in everyday devices like cell-phones and cars include accelerometers, gyros, pressure sensors, and magnetic sensors. MEMS actuators generally serve more application specific roles including micro- and nano-tweezers used for single cell manipulation, optical switching and alignment components, and micro combustion engines for high energy density power generation. MEMS rotary motors are actuators that translate an electric drive signal into rotational motion and can serve as rate calibration inputs for gyros, stages for optical components, mixing devices for micro-fluidics, etc. Existing rotary micromotors suffer from friction and wear issues that affect lifetime and performance. Attempts to alleviate friction effects include surface treatment, magnetic and electrostatic levitation, pressurized gas bearings, and micro-ball bearings. The present work demonstrates a droplet based liquid bearing supporting a rotary micromotor that improves the operating characteristics of MEMS rotary motors. The liquid bearing provides wear-free, low-friction, passive alignment between the rotor and stator. Droplets are positioned relative to the rotor and stator through patterned superhydrophobic and hydrophilic surface coatings. The liquid bearing consists of a central droplet that acts as the motor shaft, providing axial alignment between rotor and stator, and satellite droplets, analogous to ball-bearings, that provide tip and tilt stable operation. The liquid bearing friction performance is characterized through measurement of the rotational drag coefficient and minimum starting torque due to stiction and geometric effects. Bearing operational performance is further characterized by modeling and measuring stiffness, environmental survivability, and high

  8. Organic photovoltaic cells: from performance improvement to manufacturing processes.

    Science.gov (United States)

    Youn, Hongseok; Park, Hui Joon; Guo, L Jay

    2015-05-20

    Organic photovoltaics (OPVs) have been pursued as a next generation power source due to their light weight, thin, flexible, and simple fabrication advantages. Improvements in OPV efficiency have attracted great attention in the past decade. Because the functional layers in OPVs can be dissolved in common solvents, they can be manufactured by eco-friendly and scalable printing or coating technologies. In this review article, the focus is on recent efforts to control nanomorphologies of photoactive layer and discussion of various solution-processed charge transport and extraction materials, to maximize the performance of OPV cells. Next, recent works on printing and coating technologies for OPVs to realize solution processing are reviewed. The review concludes with a discussion of recent advances in the development of non-traditional lamination and transfer method towards highly efficient and fully solution-processed OPV.

  9. A Motor Imagery During Blind Action is Guided by the Same Foci of Attention as Actual Performance in a Sample Comprising Females

    Directory of Open Access Journals (Sweden)

    Bassem Khalaf

    2014-06-01

    Full Text Available There is strong evidence that focussing on the goal of an action improves performance relative to focussing on the concrete motor behaviours. The current study tests whether blind action guided by imagery relies on the same foci of attention. Thirty female participants took part in an experiment. In each condition there were 20 trials, they were asked to close their eyes and draw a straight line between two landmarks on a graphics tablet. We instructed them, in three conditions, to focus on (1 mental imagery of the goal landmark (external focus of attention, (2 drawing a straight line with the fingers (internal focus, or (3 without a specific focus of attention (control. We tested to what extent these attention instructions affected drawing performance, in terms of both deviations of the participants’ lines from an ideal straight line, and the time it took to complete the line. The study revealed that the manipulation specifically affected the deviation measure and that an external focus of attention was better than an internal focus and the control condition. These findings reveal that that mental imagery during blind action relies on same processes as actual performance. These data give perceptual representations of a direct role in motor control. They will be related to current theories of action control (constrained action hypothesis, ideomotor theories, and dual task accounts.

  10. Improving the performance of photomultiplier tubes

    Energy Technology Data Exchange (ETDEWEB)

    Harmer, S W [Department of Engineering and Technology, Manchester Metropolitan University, Manchester M1 5GD (United Kingdom); Townsend, P D, E-mail: pdtownsend@googlemail.co [Science and Technology, University of Sussex, Brighton BN1 9QH (United Kingdom)

    2010-10-20

    Photomultipliers are ubiquitous detectors of low level light signals, but their performance is limited by the complexity of photocathode technology. Two contributory problems are that light is lost both by surface reflection and by transmission through the photocathode layer. Knowledge of the dielectric constants has allowed predictive modelling of the reflectivity and absorption of the light as a function of angle of incidence, cathode thickness and polarization. The predictions have stimulated designs of extremely simple and very low cost retrofit approaches to improve the overall effectiveness of photomultipliers. One simple design presented here exploits signal that is normally lost by the surface reflection. A simple external conical torch reflector is clipped over the photomultiplier end face. The reflector raised the efficiency of an S20 multialkali photocathode by between 20% and 10% across the blue to red spectral range. An alternative semi-cylindrical glass coupler has improved the absorption efficiency by allowing the input signal to arrive at 60{sup 0} incidence to the photocathode surface, rather than normal incidence as in the standard head-on geometry. Enhancements are from 30% to 500% across the spectral range. The greater gains are at long wavelengths, and so are particularly valuable as this is the region of lowest quantum efficiency. The latter high-incidence angle approach, when applied to a low-efficiency C grade tube, has raised the performance to greater than the best of the A grade tubes, as used in the normal head-on operation. Both methods are equally applicable to other cathode compositions.

  11. Can quantization improve error performance in CDMA?

    Energy Technology Data Exchange (ETDEWEB)

    Efraim, Hadar; Yacov, Nadav; Kanter, Ido [Minerva Center and Department of Physics, Bar-Ilan University, Ramat-Gan 52900 (Israel); Shental, Ori [Center for Magnetic Recording Research (CMRR), University of California, San Diego (UCSD), 9500 Gilman Drive, La Jolla, CA 92093 (United States)], E-mail: hadar.efraim@mail.biu.ac.il, E-mail: oshental@ucsd.edu, E-mail: nadav.yacov@mail.biu.ac.il, E-mail: kanter@mail.biu.ac.il

    2008-09-12

    A K-user direct-sequence spread-spectrum code-division multiple-access (CDMA) system with (q << log{sub 2}K)-bit baseband signal quantization at the demodulator is considered. It is shown that additionally quantizing the K + 1 level output signal of the CDMA modulator into q bits improves significantly the average bit-error performance in a non-negligible regime of noise variance, {sigma}{sup 2}, and user load, {beta}, under various system settings, like additive white Gaussian noise (AWGN), Rayleigh fading, single-user detection, multi-user detection, random and orthogonal spreading codes. For the case of single-user detection in random spreading AWGN-CDMA, this regime is identified explicitly as {sigma}<{gamma}(q){radical}{beta}, where {gamma}(q) is a certain pre-factor depending on q, and the associated BER improvement is derived analytically for q = 1, 2. For the other examined system settings, computer simulations are provided, corroborating this interesting behavior.

  12. Soft Magnetic Materials for Improved Energy Performance

    Science.gov (United States)

    Willard, Matthew

    2012-02-01

    A main focus of sustainable energy research has been development of renewable energy technologies (e.g. from wind, solar, hydro, geothermal, etc.) to decrease our dependence on non-renewable energy resources (e.g. fossil fuels). By focusing on renewable energy sources now, we hope to provide enough energy resources for future generations. In parallel with this focus, it is essential to develop technologies that improve the efficiency of energy production, distribution, and consumption, to get the most from these renewable resources. Soft magnetic materials play a central role in power generation, conditioning, and conversion technologies and therefore promoting improvements in the efficiency of these materials is essential for our future energy needs. The losses generated by the magnetic core materials by hysteretic, acoustic, and/or eddy currents have a great impact on efficiency. A survey of soft magnetic materials for energy applications will be discussed with a focus on improvement in performance using novel soft magnetic materials designed for these power applications. A group of premiere soft magnetic materials -- nanocrystalline soft magnetic alloys -- will be highlighted for their potential in addressing energy efficiency. These materials are made up of nanocrystalline magnetic transition metal-rich grains embedded within an intergranular amorphous matrix, obtained by partial devitrification of melt-spun amorphous ribbons. The nanoscale grain size results in a desirable combination of large saturation induction, low coercivity, and moderate resistivity unobtainable in conventional soft magnetic alloys. The random distribution of these fine grains causes a reduction in the net magnetocrystalline anisotropy, contributing to the excellent magnetic properties. Recently developed (Fe,Co,Ni)88Zr7B4Cu1 alloys will be discussed with a focus on the microstructure/magnetic property relationship and their effects on the energy efficiency of these materials for AC

  13. Sleep deprivation and sustained attention performance: integrating mathematical and cognitive modeling.

    Science.gov (United States)

    Gunzelmann, Glenn; Gross, Joshua B; Gluck, Kevin A; Dinges, David F

    2009-07-01

    A long history of research has revealed many neurophysiological changes and concomitant behavioral impacts of sleep deprivation, sleep restriction, and circadian rhythms. Little research, however, has been conducted in the area of computational cognitive modeling to understand the information processing mechanisms through which neurobehavioral factors operate to produce degradations in human performance. Our approach to understanding this relationship is to link predictions of overall cognitive functioning, or alertness, from existing biomathematical models to information processing parameters in a cognitive architecture, leveraging the strengths from each to develop a more comprehensive explanation. The integration of these methodologies is used to account for changes in human performance on a sustained attention task across 88 h of total sleep deprivation. The integrated model captures changes due to time awake and circadian rhythms, and it also provides an account for underlying changes in the cognitive processes that give rise to those effects. The results show the potential for developing mechanistic accounts of how fatigue impacts cognition, and they illustrate the increased explanatory power that is possible by combining theoretical insights from multiple methodologies.

  14. White matter microstructure and developmental improvement of hyperactive/impulsive symptoms in Attention-Deficit/Hyperactivity Disorder

    NARCIS (Netherlands)

    Francx, W.C.L.; Zwiers, M.P.; Mennes, M.J.J.; Oosterlaan, J.; Heslenfeld, D.J.; Hoekstra, P.J.; Hartman, C.A.; Franke, B.; Faraone, S.V; O'Dwyer, L.G.; Buitelaar, J.

    2015-01-01

    Background A developmental improvement of symptoms in Attention-Deficit/Hyperactivity Disorder (ADHD) is frequently reported, but the underlying neurobiological substrate has not been identified. The aim of this study was to determine whether white matter microstructure is related to developmental i

  15. White matter microstructure and developmental improvement of hyperactive/impulsive symptoms in attention-deficit/hyperactivity disorder

    NARCIS (Netherlands)

    Francx, Winke; Zwiers, Marcel P.; Mennes, Maarten; Oosterlaan, Jaap; Heslenfeld, Dirk; Hoekstra, Pieter J.; Hartman, Catharina A.; Franke, Barbara; Faraone, Stephen V.; O'Dwyer, Laurence; Buitelaar, Jan K.

    2015-01-01

    Background: A developmental improvement of symptoms in attention-deficit/hyperactivity disorder (ADHD) is frequently reported, but the underlying neurobiological substrate has not been identified. The aim of this study was to determine whether white matter microstructure is related to developmental

  16. Effects of amphetamine and methylphenidate on attentional performance and impulsivity in the mouse 5-Choice Serial Reaction Time Task

    DEFF Research Database (Denmark)

    Caballero Puntiverio, Maitane; Fitzpatrick, Ciarán Martin; Woldbye, David Paul Drucker

    2017-01-01

    Background: Few studies have investigated the effects of conventional attention deficit-hyperactivity disorder (ADHD) medication in the mouse 5-choice serial reaction time task (5-CSRTT), and rat studies have yielded inconsistent results. Objective: We aimed to examine the effects of acute...... assessed. Saline treatment data determined high- and lowattentive (LA), and high- and low-impulsive (LI) subgroups according to the upper and lower 30th percentiles, respectively. Results: In the LA subgroup accuracy was improved by 0.5 mg/kg AMPH and 2 mg/kg MPH, while no effect was found in the high-attentive......-CSRTT when investigating drug effects on attention and impulsivity....

  17. Attentional Focus Effects in Standing Long Jump Performance: Influence of a Broad and Narrow Internal Focus.

    Science.gov (United States)

    Becker, Kevin A; Smith, Peter J K

    2015-07-01

    The content of instructions that strength coaches give can have a significant impact on how an athlete or client performs. Research on motor learning has shown an advantage of instructions focusing on the effects of movements (external focus) over those focusing on the movements themselves (internal focus) in the performance of motor skills. Internally focused cues are abundant in coaching, therefore the purpose of this study was to test whether some internally focused cues might be more helpful than others. Participants (68) were randomly assigned to either an external focus (EX), broad internal focus (B-IN), narrow internal focus (N-IN), or a control group (CON), and performed 5 standing long jumps. All groups were instructed that the goal was to jump as far as possible. In addition, the EX group was told to "jump as far past the start line as possible." The B-IN group was told to "use your legs." The N-IN group was told to "extend your knees as rapidly as possible," and the CON group received no additional instruction. An analysis of covariance showed that the EX group (198.09 ± 31.89 cm) jumped significantly farther than both the B-IN group (173.74 ± 35.36 cm), p = 0.010 and the N-IN group (178.53 ± 31.17 cm), p = 0.049, with no group different from the CON group. The results suggest that a broad internal focus is no more effective than a narrow internal focus, and that an external focus leads to the greatest jump distance. Strength and conditioning professionals should carefully word their instructions to induce an external focus of attention whenever possible.

  18. Nanotechnological inventions considerably improve performance characteristics

    Directory of Open Access Journals (Sweden)

    VLASOV Vladimir Alexeevich

    2014-06-01

    Full Text Available The invention «The method of production of carbon nanomaterial (RU 2509053» can be used as an additive for concretes and polymers which significantly improves their performance characteristics. The method of production of carbon nanomaterial consists of the following stages: preliminary preparation of sphagnous moss when it is refined from foreign admixtures, dried up to 10% humidity and ground, then ground material is exposed to pyrolysis under the temperature 850–950оC for 1–2 hours and cooled up to the environment temperature. After that amorphous carbon obtained in pyrolysis is treated with mechanical activation in the variable planetary mill for 7–10 hours. The invention makes it possible to provide increased outcome of nanotubes with high cleanliness. The invention «The method of production of nanodispersed metal powders and alloys of them (RU 2509626» relates to the powder metallurgy. Powder metal chloride or powder mixture at least of two metal chlorides is treated in the environment of the water steam which is supplied in reaction space at the rate of 50–100 ml/min at the temperature 400–800оC at the presence of absorbent carbon or introducing carbon oxide (II obtained during dissolution of formic acid HCOOH. The invention provides reliable production of nanodispersed metal powders and alloys of them from 3-d metal range: Ni, Co, Cu, Fe, Zn which can be used in powder metallurgy to improve baking process, in chemical industry as the fillers of polymers and reaction catalysts; as additives to anticorrosive covers, etc.

  19. Effects of methylphenidate on acute math performance in children with attention-deficit hyperactivity disorder.

    Science.gov (United States)

    Grizenko, Natalie; Cai, Emmy; Jolicoeur, Claude; Ter-Stepanian, Mariam; Joober, Ridha

    2013-11-01

    Objectif : Examiner les effets à court terme (aigus) du méthylphénidate (MPH) sur la performance en mathématique chez des enfants souffrant du trouble de déficit de l’attention avec hyperactivité (TDAH), et quels facteurs prédisent une amélioration de la performance en math. Méthode : Cent quatre-vingt-dix-huit enfants souffrant du TDAH ont participé à un essai de MPH croisé, randomisé, à double insu et contrôlé avec placebo. La réponse du MPH en math a été déterminée par l’administration de problèmes de math ajustés à leur niveau scolaire durant la Restricted Academic Situation Scale (RASS). Les tests t de Student ont été menés afin d’évaluer le changement de la performance en math avec les psychostimulants. La corrélation entre le changement à la RASS et le changement de la performance en math a aussi été examinée. Une régression linéaire a été exécutée pour déterminer les variables prédictives. Résultats : Les enfants souffrant du TDAH se sont améliorés significativement en math avec le MPH (P math avec MPH était hautement corrélé. L’âge de l’enfant au départ et les scores normaux au départ au Wechsler Individual Achievement Test (WIAT) – des opérations numériques représentaient 15 % des variances d’amélioration aiguë en math. Conclusions : Le MPH améliore la performance aiguë en mathématique chez les enfants souffrant du TDAH. Les enfants plus jeunes qui ont de moins bons scores en math (évalué par le WIAT) ont surtout amélioré leurs scores en math lorsqu’ils ont reçu des psychostimulants. Numéro d’enregistrement d’essai clinique : NCT00483106.

  20. Students Pay Attention! Combating the Vigilance Decrement to Improve Learning during Lectures

    Science.gov (United States)

    Young, Mark S.; Robinson, Stephanie; Alberts, Phil

    2009-01-01

    Maintaining student concentration in lectures has long been a challenge for lecturers. Pedagogical research consistently finds a drop in attention between 10 and 30 minutes into the lecture, which has been associated with the passive nature of the standard format, and has consequences for learning approaches and outcomes. A similar phenomenon has…

  1. Self-Alert Training: Volitional Modulation of Autonomic Arousal Improves Sustained Attention

    Science.gov (United States)

    O'Connell, Redmond G.; Bellgrove, Mark A.; Dockree, Paul M.; Lau, Adam; Fitzgerald, Michael; Robertson, Ian H.

    2008-01-01

    The present study examines a new alertness training strategy (Self-Alert Training, SAT) designed to explore the relationship between the top-down control processes governing arousal and sustained attention. In order to maximally target frontal control systems SAT combines a previously validated behavioural self-alerting technique [Robertson, I.…

  2. Using Virtual Reality Environment to Improve Joint Attention Associated with Pervasive Developmental Disorder

    Science.gov (United States)

    Cheng, Yufang; Huang, Ruowen

    2012-01-01

    The focus of this study is using data glove to practice Joint attention skill in virtual reality environment for people with pervasive developmental disorder (PDD). The virtual reality environment provides a safe environment for PDD people. Especially, when they made errors during practice in virtual reality environment, there is no suffering or…

  3. Improving Robustness against Environmental Sounds for Directing Attention of Social Robots

    DEFF Research Database (Denmark)

    Thomsen, Nicolai Bæk; Tan, Zheng-Hua; Lindberg, Børge;

    2015-01-01

    This paper presents a multi-modal system for finding out where to direct the attention of a social robot in a dialog scenario, which is robust against environmental sounds (door slamming, phone ringing etc.) and short speech segments. The method is based on combining voice activity detection (VAD...

  4. Auditory Stream Segregation Improves Infants' Selective Attention to Target Tones Amid Distracters

    Science.gov (United States)

    Smith, Nicholas A.; Trainor, Laurel J.

    2011-01-01

    This study examined the role of auditory stream segregation in the selective attention to target tones in infancy. Using a task adapted from Bregman and Rudnicky's 1975 study and implemented in a conditioned head-turn procedure, infant and adult listeners had to discriminate the temporal order of 2,200 and 2,400 Hz target tones presented alone,…

  5. Decreasing Internal Focus of Attention Improves Postural Control during Quiet Standing in Young Healthy Adults

    Science.gov (United States)

    Nafati, Gilel; Vuillerme, Nicolas

    2011-01-01

    This experiment was designed to investigate whether and how decreasing the amount of attentional focus invested in postural control could affect bipedal postural control. Twelve participants were asked to stand upright as immobile as possible on a force platform in one control condition and one cognitive condition. In the latter condition, they…

  6. Meditation increases the depth of information processing and improves the allocation of attention in space.

    Science.gov (United States)

    van Leeuwen, Sara; Singer, Wolf; Melloni, Lucia

    2012-01-01

    During meditation, practitioners are required to center their attention on a specific object for extended periods of time. When their thoughts get diverted, they learn to quickly disengage from the distracter. We hypothesized that learning to respond to the dual demand of engaging attention on specific objects and disengaging quickly from distracters enhances the efficiency by which meditation practitioners can allocate attention. We tested this hypothesis in a global-to-local task while measuring electroencephalographic activity from a group of eight highly trained Buddhist monks and nuns and a group of eight age and education matched controls with no previous meditation experience. Specifically, we investigated the effect of attentional training on the global precedence effect, i.e., faster detection of targets on a global than on a local level. We expected to find a reduced global precedence effect in meditation practitioners but not in controls, reflecting that meditators can more quickly disengage their attention from the dominant global level. Analysis of reaction times confirmed this prediction. To investigate the underlying changes in brain activity and their time course, we analyzed event-related potentials. Meditators showed an enhanced ability to select the respective target level, as reflected by enhanced processing of target level information. In contrast with control group, which showed a local target selection effect only in the P1 and a global target selection effect in the P3 component, meditators showed effects of local information processing in the P1, N2, and P3 and of global processing for the N1, N2, and P3. Thus, meditators seem to display enhanced depth of processing. In addition, meditation altered the uptake of information such that meditators selected target level information earlier in the processing sequence than controls. In a longitudinal experiment, we could replicate the behavioral effects, suggesting that meditation modulates

  7. Written Composition Performance of Students with Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Casas, Ana Miranda; Ferrer, Manuel Soriano; Fortea, Inmaculada Baixauli

    2013-01-01

    Attention-deficit/hyperactivity disorder (ADHD) is frequently associated with learning disabilities. The present study examined the written composition of children with ADHD, which depends to a large degree on continuous self-regulation and attentional control skills for organizing information and maintaining the level of effort. Fifty children…

  8. The role of time on task performance in modifying the effects of gum chewing on attention

    NARCIS (Netherlands)

    Tucha, Lara; Simpson, William

    2011-01-01

    Recent research examined the effects of chewing gum on attention and reported a significant interaction of gum chewing with time. Using a crossover within-subject design, the present study examined the effect of gum chewing on sustained attention in healthy adults over a period of 30 min. The result

  9. Meditation increases the depth of information processing and improves the allocation of attention in space

    Directory of Open Access Journals (Sweden)

    Sara evan Leeuwen

    2012-05-01

    Full Text Available During meditation, practitioners are required to center their attention on a specific object for extended periods of time. When their thoughts get diverted, they learn to quickly disengage from the distracter. We hypothesized that learning to respond to the dual demand of engaging attention on specific objects and disengaging quickly from distracters enhances the efficiency by which meditation practitioners can allocate attention. We tested this hypothesis in a global-to-local task while measuring electroencephalographic activity from a group of eight highly trained Buddhist monks and nuns and a group of eight age and education matched controls with no previous meditation experience. Specifically, we investigated the effect of attentional training on the global precedence effect, i.e., faster detection of targets on a global than on a local level. We expected to find a reduced global precedence effect in meditation practitioners but not in controls, reflecting that meditators can more quickly disengage their attention from the dominant global level. Analysis of reaction times confirmed this prediction. To investigate the underlying changes in brain activity and their time course, we analyzed event-related potentials. Meditators showed an enhanced ability to select the respective target level, as reflected by enhanced processing of target level information. In contrast with control group, which showed a local target selection effect only in the P1 and a global target selection effect in the P3 component, meditators showed effects of local information processing in the P1, N2 and P3 and of global processing for the N1, N2 and P3. Thus, meditators seem to display enhanced depth of processing. In addition, meditation altered the uptake of information such that meditators selected target level information earlier in the processing sequence than controls. In a longitudinal experiment, we could replicate the behavioral effects, suggesting that

  10. Ideal Strategy to Improve Datawarehouse Performance

    Directory of Open Access Journals (Sweden)

    Fahad Sultan

    2010-03-01

    Full Text Available Data warehouse is set up for the benefits of business analysts and executives across all functional areas. The primary goal of data warehouse is to free the information locked up in the operational database so that decision makers and business analyst can make queries, analysis and planning regardless of the data changes inoperational database. Data analysis in a large database requires some innovative techniques; there should be some new methods and procedures to look at the data with different angles. While executing adhoc queries over a large database degrade the query performance atconsiderable level because query will have to go through from large volume of data after making lot of joins. Moreover, as the number of queries is large, therefore, in certain cases there is reasonable probability that same query submitted by the one or multiple users at different times. Each time when query is executed, all the data ofwarehouse is analyzed to generate the result of that query. In this paper we purpose an ideal approach which definitely minimizes esponse time and improves the efficiency of data warehouse overall, articularly when data warehouse is updated at regular interval. Thisapproach has been validated by Formal Method.

  11. EDUCATIONAL POLICIES AND INITIATIVES FOR IMPROVED PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Flavia, CAIA

    2015-03-01

    Full Text Available According to Gartner estimates, due to increased variety, speed and data volume, by 2015 there will be a global demand of 4.4 million professionals for real-time analysis of data from sources with different structures, but only one third of the demand will be met. The purpose of this research is to identify possible solutions for improved academic results in the IT domain, considering the time management policies, the content and the student motivations, as well as the business strategy tendencies. These proposals are targeted toward meeting the IT specialists demand. The research is composed of two parts: the first explores the Romanian IT labour market characteristics, while the second investigates the academic education policies that can help mitigate deficiencies and attain higher performance. The deficiencies are identified through a series of statistical research and analysis based on national level databases, adopting a quantitative approach. The policies proposed are supported by a flow model developed considering the students' activity, motivation, traits and results, measured and analysed quantitatively.

  12. Learning to improve path planning performance

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Pang C.

    1995-04-01

    In robotics, path planning refers to finding a short. collision-free path from an initial robot configuration to a desired configuratioin. It has to be fast to support real-time task-level robot programming. Unfortunately, current planning techniques are still too slow to be effective, as they often require several minutes, if not hours of computation. To remedy this situation, we present and analyze a learning algorithm that uses past experience to increase future performance. The algorithm relies on an existing path planner to provide solutions to difficult tasks. From these solutions, an evolving sparse network of useful robot configurations is learned to support faster planning. More generally, the algorithm provides a speedup-learning framework in which a slow but capable planner may be improved both cost-wise and capability-wise by a faster but less capable planner coupled with experience. The basic algorithm is suitable for stationary environments, and can be extended to accommodate changing environments with on-demand experience repair and object-attached experience abstraction. To analyze the algorithm, we characterize the situations in which the adaptive planner is useful, provide quantitative bounds to predict its behavior, and confirm our theoretical results with experiments in path planning of manipulators. Our algorithm and analysis are sufficiently, general that they may also be applied to other planning domains in which experience is useful.

  13. Expectation of having consumed caffeine can improve performance and mood

    OpenAIRE

    Dawkins, Lynne; Shahzad, Fatima-Zahra; Ahmed, Suada S.; Edmonds, Caroline J.

    2011-01-01

    We explored whether caffeine, and expectation of having consumed caffeine, affects attention, reward responsivity and mood using double-blinded methodology. 88 participants were randomly allocated to ‘drink-type’ (caffeinated/decaffeinated coffee) and ‘expectancy’ (told caffeinated/told decaffeinated coffee) manipulations. Both caffeine and expectation of having consumed caffeine improved attention and psychomotor speed. Expectation enhanced self-reported vigour and reward responsivity. Self-...

  14. Response Switching Process in Children with Attention-Deficit-Hyperactivity Disorder on the Novel Continuous Performance Test

    Science.gov (United States)

    Inoue, Yuki; Inagaki, Masumi; Gunji, Atsuko; Furushima, Wakana; Kaga, Makiko

    2008-01-01

    We examined the effects of previous trials on subsequent trials on performance in the continuous performance test (CPT) in children with attention-deficit-hyperactivity disorder (ADHD). Thirty-five non-medicated children with ADHD (31 males, four females; mean age 9y 10mo [SD 2y 4mo]) and 33 comparison children (20 males, 13 females; mean age 10y…

  15. The benefit of hippotherapy for improvement of attention and memory in children with cerebral palsy: A pilot study

    Directory of Open Access Journals (Sweden)

    Eva Krejčí

    2015-03-01

    Full Text Available Background: The research is based on an assumption that the hypokinesia induced by cerebral palsy (CP leads to inhibition of some mental functions. The method we used to treat patients with CP, hippotherapy (HT, is a treatment using horses and belongs to proprioceptive-neuromuscular-facilitative methods. Objective: The aim of the research was to determine the benefit of HT on attention and memory of patients with CP. Methods: There were two groups of patients: short-term HT (n = 11; 8 females and 3 males, age 15.4 ± 5.3 years and long-term HT (n = 9; 7 females and 2 males, age 10.8 ± 2.7 years. The short-term HT group participated in daily 30 minute-long HT sessions for duration of a week-long summer therapy camp; while with the long-term HT group, HT sessions of the same length were used weekly for 5-6 weeks. Attention and memory skills were assessed with "Numeric square test" and "Verbal learning test", respectively. Both tests were undertaken before starting and after concluding the camp or the 5-6 week long HT period. Results: Attention improvement demonstrated in a significant decrease of an average time of "Numeric square test". The improvement was seen in both long-term HT (15.7 seconds overall average time reduction after HT, p < .01 and short-term HT (20.8 seconds reduction, p < .01 groups. Short-term memory improvement was found in the long-term HT group, demonstrated by a higher number of memorized words (more than half of the patients memorized on average 10.5 more words after HT (p < .05. While the short-term HT group did not show significant improvement of attention or short-term memory, the average number of memorized words after a diversion of attention and a 30 minute delay increased by 4.1, showing an improvement (p < .05 of long-term memory. Conclusions: Our results suggest that hippotherapy as a part of comprehensive therapy in patients with CP leads to improvement of memory and

  16. Using business intelligence to improve performance.

    Science.gov (United States)

    Wadsworth, Tom; Graves, Brian; Glass, Steve; Harrison, A Marc; Donovan, Chris; Proctor, Andrew

    2009-10-01

    Cleveland Clinic's enterprise performance management program offers proof that comparisons of actual performance against strategic objectives can enable healthcare organization to achieve rapid organizational change. Here are four lessons Cleveland Clinic learned from this initiative: Align performance metrics with strategic initiatives. Structure dashboards for the CEO. Link performance to annual reviews. Customize dashboard views to the specific user.

  17. No improvement in endurance performance after a single dose of beetroot juice.

    NARCIS (Netherlands)

    Cermak, N.M.; Res, P.; Stinkens, R.E.; Lundberg, J.O.; Gibala, M.J.; van Loon, L.J.C.

    2012-01-01

    INTRODUCTION: Dietary nitrate supplementation has received much attention in the literature due to its proposed ergogenic properties. Recently, the ingestion of a single bolus of nitrate-rich beetroot juice (500 mL; ~6.2 mmol NO3-) was reported to improve subsequent time trial performance. However,

  18. Performance monitoring and executive control of attention in euthymic bipolar disorder: employing the CPT-AX paradigm.

    Science.gov (United States)

    Robinson, Lucy J; Thompson, Jill M; Gallagher, Peter; Gray, John M; Young, Allan H; Ferrier, I Nicol

    2013-12-15

    Reduced cognitive test performance has been demonstrated in patients with bipolar disorder (BD), even when euthymic. Several studies have explored aspects of attention, including sustained attention, and reported patients show lower accuracy compared to controls. It is necessary to modify existing attentional paradigms to fully characterise such deficits. The present study sought to examine if there are changes in the profile of performance and error-types during a sustained attention task in BD. Twenty-two euthymic patients with DSM-IV diagnosed BD and 21 healthy controls were recruited. Participants completed a modified CPT-AX paradigm with a high proportion of target trials (70%) with cues and probes presented at continuous intervals. This modification increases the demands on response inhibition and permits the deconstruction of attentional/executive deficits previously described. Overall, BD patients showed significantly poorer target discriminability compared to controls. In block one (first quarter) of the task, patients showed no significant differences to controls, but by the final fourth block (last quarter) they made significantly fewer hits and more errors (both 'AX' misses and 'BX' false alarms). BD patients completed initial stages of the task similarly to controls, but as demands on the attentional system continued difficulties emerged, consistent with problems in context-maintenance.

  19. Improvement of executive functions in boys with attention deficit hyperactivity disorder: an open-label follow-up study with once-daily atomoxetine.

    Science.gov (United States)

    Gau, Susan Shur-Fen; Shang, Chi-Yung

    2010-03-01

    Atomoxetine is efficacious in reducing symptoms of attention deficit hyperactivity disorder (ADHD) but its effect on executive functions needs more investigation. We examined the effect of atomoxetine on a wide range of non-verbal executive functions among 30 drug-naive male patients with DSM-IV ADHD, aged 8-16 yr, in an open-label 12-wk atomoxetine treatment trial. Before administration of atomoxetine, the participants were assessed by psychiatric interviews, the WISC-III, and the tasks involving executive functions of the Cambridge Neuropsychological Test Automated Battery (CANTAB): Intra-dimensional/Extra-dimensional Shifts (IED), Rapid Visual Information Processing (RVIP), Spatial Span (SSP), Spatial Working Memory (SWM), and Stockings of Cambridge (SOC); and reassessed at weeks 4 and 12. All the raw scores of the CANTAB were transformed to z scores based on a normative sample of 180 children aged 8-16 yr. Results showed significant improvement in executive functions after treatment with atomoxetine for 4 wk or 12 wk including improved shifting and flexibility of attention in the IED; improved spatial short-term memory in the SSP; improved sustained attention and increased response inhibition in the RVIP; improved spatial working memory in the SWM; and improved spatial planning and problem solving in the SOC. Our findings suggested that atomoxetine was associated with significant improvement in various non-verbal executive functions among boys with ADHD, in addition to its well-known efficacy in ADHD-related symptom reductions. However, owing to lack of a placebo-controlled trial design, the findings should be interpreted with caution that changes in performance may be due to practice effects.

  20. Microsoft Kinect-based Continuous Performance Test: An Objective Attention Deficit Hyperactivity Disorder Assessment

    Science.gov (United States)

    Delgado-Gomez, David; Masó-Besga, Antonio Eduardo; Vallejo-Oñate, Silvia; Baltasar Tello, Itziar; Arrua Duarte, Elsa; Vera Varela, María Constanza; Carballo, Juan; Baca-García, Enrique

    2017-01-01

    Background One of the major challenges in mental medical care is finding out new instruments for an accurate and objective evaluation of the attention deficit hyperactivity disorder (ADHD). Early ADHD identification, severity assessment, and prompt treatment are essential to avoid the negative effects associated with this mental condition. Objective The aim of our study was to develop a novel ADHD assessment instrument based on Microsoft Kinect, which identifies ADHD cardinal symptoms in order to provide a more accurate evaluation. Methods A group of 30 children, aged 8-12 years (10.3 [SD 1.4]; male 70% [21/30]), who were referred to the Child and Adolescent Psychiatry Unit of the Department of Psychiatry at Fundación Jiménez Díaz Hospital (Madrid, Spain), were included in this study. Children were required to meet the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria of ADHD diagnosis. One of the parents or guardians of the children filled the Spanish version of the Strengths and Weaknesses of ADHD Symptoms and Normal Behavior (SWAN) rating scale used in clinical practice. Each child conducted a Kinect-based continuous performance test (CPT) in which the reaction time (RT), the commission errors, and the time required to complete the reaction (CT) were calculated. The correlations of the 3 predictors, obtained using Kinect methodology, with respect to the scores of the SWAN scale were calculated. Results The RT achieved a correlation of -.11, -.29, and -.37 with respect to the inattention, hyperactivity, and impulsivity factors of the SWAN scale. The correlations of the commission error with respect to these 3 factors were -.03, .01, and .24, respectively. Conclusions Our findings show a relation between the Microsoft Kinect-based version of the CPT and ADHD symptomatology assessed through parental report. Results point out the importance of future research on the development of objective measures for the diagnosis of ADHD among children

  1. Central as well as peripheral attentional bottlenecks in dual-task performance activate lateral prefrontal cortices

    Directory of Open Access Journals (Sweden)

    Andre J Szameitat

    2016-03-01

    Full Text Available Human information processing suffers from severe limitations in parallel processing. In particular, when required to respond to two stimuli in rapid succession, processing bottlenecks may appear at central and peripheral stages of task processing. Importantly, it has been suggested that executive functions are needed to resolve the interference arising at such bottlenecks. The aims of the present study were to test whether central attentional limitations (i.e., bottleneck at the decisional response selection stage as well as peripheral limitations (i.e., bottleneck at response initiation both demand executive functions located in the lateral prefrontal cortex. For this, we re-analysed two previous studies, in which a total of 33 participants performed a dual-task according to the paradigm of the psychological refractory period (PRP during fMRI. In one study (N=17, the PRP task consisted of two two-choice response tasks known to suffer from a central bottleneck (CB group. In the other study (N=16, the PRP task consisted of two simple-response tasks known to suffer from a peripheral bottleneck (PB group. Both groups showed considerable dual-task costs in form of slowing of the second response in the dual-task (PRP effect. Imaging results are based on the subtraction of both single-tasks from the dual-task within each group. In the CB group, the bilateral middle frontal gyri and inferior frontal gyri were activated. Higher activation in these areas was associated with lower dual-task costs. In the PB group, the right middle frontal and inferior frontal gyrus were activated. Here, higher activation was associated with higher dual-task costs. In conclusion we suggest that central and peripheral bottlenecks both demand executive functions located in lateral prefrontal cortices. Differences between the CB and PB groups with respect to the exact prefrontal areas activated and the correlational patterns suggest that the executive functions resolving

  2. On the temporal characteristics of performance variability in attention deficit hyperactivity disorder (ADHD.

    Directory of Open Access Journals (Sweden)

    Bernd Feige

    Full Text Available Increased intra-subject variability of reaction times (ISV-RT is one of the most consistent findings in attention-deficit/hyperactivity disorder (ADHD. Although the nature of this phenomenon is still unclear, it has been hypothesised to reflect interference from the Default Mode Network (DMN. So far, ISV-RT has been operationally defined either as a frequency spectrum of the underlying RT time series, or as a measure of dispersion of the RT scores distribution. Here, we use a novel RT analysis framework to link these hitherto unconnected facets of ISV-RT by determining the sensitivity of different measures of RT dispersion to the frequency content of the underlying RT time series. N=27 patients with ADHD and N=26 healthy controls performed several visual N-back tasks. Different measures of RT dispersion were repeatedly modelled after individual frequency bands of the underlying RT time series had been either extracted or suppressed using frequency-domain filtering. We found that the intra-subject standard deviation of RT preserves the "1/f noise" characteristic typical of human RT data. Furthermore and most importantly, we found that the ex-Gaussian parameter τ is rather exclusively sensitive to frequencies below 0.025 Hz in the underlying RT time series and that the particularly slow RTs, which nourish τ, occur regularly as part of an quasi-periodic, ultra-slow RT fluctuation. Overall, our results are compatible with the idea that ISV-RT is modulated by an endogenous, slowly fluctuating process that may reflect DMN interference.

  3. Spatial and sustained attention in relation to smoking status: behavioural performance and brain activation patterns.

    Science.gov (United States)

    Vossel, Simone; Warbrick, Tracy; Mobascher, Arian; Winterer, Georg; Fink, Gereon R

    2011-11-01

    Nicotine enhances attentional functions. Since chronic nicotine exposure through smoking induces neuroadaptive changes in the brain at a structural and molecular level, the present functional MRI (fMRI) study aimed at investigating the neural mechanisms underlying visuospatial and sustained attention in smokers and non-smokers. Visuospatial attention was assessed with a location-cueing paradigm, while sustained attention was measured by changes in response speed over time. During invalid trials, neural activity within the basal forebrain was selectively enhanced in smokers and higher basal forebrain activity was associated with increased parietal cortex activation. Moreover, higher levels of expired carbon monoxide in smokers before scanning were associated with higher parietal cortex activation and faster responses to invalidly cued targets. Smokers showed a slowing of responses and additionally recruited an area within the right supramarginal gyrus with increasing time on task. Activity decreases over time were observed in visual areas in smokers. The data provide evidence for altered attentional functions in smokers as compared with non-smokers, which were partly modulated by residual nicotine levels and were observed at a behavioural level for sustained and at a neural level for spatial and sustained attention.

  4. Attentional and visual demands for sprint performance in non-fatigued and fatigued conditions: reliability of a repeated sprint test

    Directory of Open Access Journals (Sweden)

    Diercks Ron L

    2010-05-01

    Full Text Available Abstract Background Physical performance measures are widely used to assess physical function, providing information about physiological and biomechanical aspects of motor performance. However they do not provide insight into the attentional and visual demands for motor performance. A figure-of-eight sprint test was therefore developed to measure the attentional and visual demands for repeated-sprint performance. The aims of the study were: 1 to assess test-retest reliability of the figure-of-eight sprint test, and 2 to study the attentional and visual demands for sprint performance in a non-fatigued and fatigued condition. Methods Twenty-seven healthy athletes were included in the study. To determine test-retest reliability, a subgroup of 19 athletes performed the figure-of-eight sprint test twice. The figure-of-eight sprint test consisted of nine 30-second sprints. The sprint test consisted of three test parts: sprinting without any restriction, with an attention-demanding task, and with restricted vision. Increases in sprint times with the attention-demanding task or restricted vision are reflective of the attentional and visual demands for sprinting. Intraclass correlation coefficients (ICCs and mean difference between test and retest with 95% confidence limits (CL were used to assess test-retest reliability. Repeated-measures ANOVA were used for comparisons between the sprint times and fatigue measurements of the test parts in both a non-fatigued and fatigued condition. Results The figure-of-eight sprint test showed good test-retest reliability, with ICCs ranging from 0.75 to 0.94 (95% CL: 0.40-0.98. Zero lay within the 95% CL of the mean differences, indicating that no bias existed between sprint performance at test and retest. Sprint times during the test parts with attention-demanding task (P = 0.01 and restricted vision (P Conclusions High ICCs and the absence of systematic variation indicate good test-retest reliability of the figure

  5. Sootblowing optimization for improved boiler performance

    Science.gov (United States)

    James, John Robert; McDermott, John; Piche, Stephen; Pickard, Fred; Parikh, Neel J

    2013-07-30

    A sootblowing control system that uses predictive models to bridge the gap between sootblower operation and boiler performance goals. The system uses predictive modeling and heuristics (rules) associated with different zones in a boiler to determine an optimal sequence of sootblower operations and achieve boiler performance targets. The system performs the sootblower optimization while observing any operational constraints placed on the sootblowers.

  6. Improved quality of life among adolescents with attention-deficit/hyperactivity disorder is mediated by protective factors

    DEFF Research Database (Denmark)

    Schei, Jorun; Nøvik, Torunn Stene; Thomsen, Per Hove;

    2015-01-01

    BACKGROUND: The aim of this study was to assess the role of protective factors as mediators and/or moderators of the relationship between coexisting emotional and conduct problems and quality of life (QoL) among adolescents with attention-deficit/hyperactivity disorder (ADHD). METHODS: The sample......, and family cohesion may identify potential treatment goals for adolescents with ADHD and coexisting problems, and may contribute to improvements in QoL....

  7. Performance samples on academic tasks : improving prediction of academic performance

    NARCIS (Netherlands)

    Tanilon, Jenny

    2011-01-01

    This thesis is about the development and validation of a performance-based test, labeled as Performance Samples on academic tasks in Education and Child Studies (PSEd). PSEd is designed to identify students who are most able to perform the academic tasks involved in an Education and Child Studies br

  8. Attention deficit associated with early life interictal spikes in a rat model is improved with ACTH.

    Directory of Open Access Journals (Sweden)

    Amanda E Hernan

    Full Text Available Children with epilepsy often present with pervasive cognitive and behavioral comorbidities including working memory impairments, attention deficit hyperactivity disorder (ADHD and autism spectrum disorder. These non-seizure characteristics are severely detrimental to overall quality of life. Some of these children, particularly those with epilepsies classified as Landau-Kleffner Syndrome or continuous spike and wave during sleep, have infrequent seizure activity but frequent focal epileptiform activity. This frequent epileptiform activity is thought to be detrimental to cognitive development; however, it is also possible that these IIS events initiate pathophysiological pathways in the developing brain that may be independently associated with cognitive deficits. These hypotheses are difficult to address due to the previous lack of an appropriate animal model. To this end, we have recently developed a rat model to test the role of frequent focal epileptiform activity in the prefrontal cortex. Using microinjections of a GABA(A antagonist (bicuculline methiodine delivered multiple times per day from postnatal day (p 21 to p25, we showed that rat pups experiencing frequent, focal, recurrent epileptiform activity in the form of interictal spikes during neurodevelopment have significant long-term deficits in attention and sociability that persist into adulthood. To determine if treatment with ACTH, a drug widely used to treat early-life seizures, altered outcome we administered ACTH once per day subcutaneously during the time of the induced interictal spike activity. We show a modest amelioration of the attention deficit seen in animals with a history of early life interictal spikes with ACTH, in the absence of alteration of interictal spike activity. These results suggest that pharmacological intervention that is not targeted to the interictal spike activity is worthy of future study as it may be beneficial for preventing or ameliorating adverse

  9. How design can improve company performance

    NARCIS (Netherlands)

    J.C.M. van den Ende (Jan); M. Candi (Marina); G. Gemser (Gerda)

    2010-01-01

    textabstractEmphasising design and including designers in product development teams contributes to new product success. Likewise, involving designers in developing websites and corporate visual identity helps to improve firm image. When taken together this can contribute to improved company performa

  10. Football to Improve Math and Reading Performance

    Science.gov (United States)

    Van Klaveren, Chris; De Witte, Kristof

    2015-01-01

    Schools frequently increase the instructional time to improve primary school children's math and reading skills. There is, however, little evidence that math and reading skills are effectively improved by these instruction-time increases. This study evaluates "Playing for Success" (PfS), an extended school day program for underachieving…

  11. The role of skin conductance level reactivity in the impact of children's exposure to interparental conflict on their attention performance.

    Science.gov (United States)

    Zemp, Martina; Bodenmann, Guy; Mark Cummings, E

    2014-02-01

    Previous research suggests that undermining of attention performance might be one decisive underlying mechanism in the link between marital conflict and children's academic maladjustment, but little is known about specific risk patterns in this regard. This study examines, in an experimental approach, the role of children's history of interparental discord and skin conductance level reactivity (SCLR) as moderators in the link between analogue marital conflict exposure and children's attention. The attention performance of 57 children, aged 11 to 13 years, was assessed prior to and immediately after a 1-min video exposure to either (a) a couple conflict or (b) a neutral condition. SCLR was measured continuously throughout the stimulus presentation. Results indicated that children's family background of interparental conflict and their physiological reactivity moderated the influence of the experimental stimulus on children's short-term attention performance. Lower SCLR served as a protective factor in children from high-conflict homes exposed to the couple conflict. The current study advances the body of knowledge in this field by identifying risk patterns for the development of attention problems in children in relation to marital conflict exposure.

  12. Neurophysiological signals of ignoring and attending are separable and related to performance during sustained intersensory attention.

    Science.gov (United States)

    Lenartowicz, Agatha; Simpson, Gregory V; Haber, Catherine M; Cohen, Mark S

    2014-09-01

    The ability to attend to an input selectively while ignoring distracting sensations is thought to depend on the coordination of two processes: enhancement of target signals and attenuation of distractor signals. This implies that attending and ignoring may be dissociable neural processes and that they make separable contributions to behavioral outcomes of attention. In this study, we tested these hypotheses in the context of sustained attention by measuring neurophysiological responses to attended and ignored stimuli in a noncued, continuous, audiovisual selective attention task. We compared these against responses during a passive control to quantify effects of attending and ignoring separately. In both sensory modalities, responses to ignored stimuli were attenuated relative to a passive control, whereas responses to attended stimuli were enhanced. The scalp topographies and brain activations of these modulatory effects were consistent with the sensory regions that process each modality. They also included parietal and prefrontal activations that suggest these effects arise from interactions between top-down and sensory cortices. Most importantly, we found that both attending and ignoring processes contributed to task accuracy and that these effects were not correlated--suggesting unique neural trajectories. This conclusion was supported by the novel observation that attending and ignoring differed in timing and in active cortical regions. The data provide direct evidence for the separable contributions of attending and ignoring to behavioral outcomes of attention control during sustained intersensory attention.

  13. Improving Performance Of Industrial Enterprises With CGT

    Science.gov (United States)

    Dolgih, I. N.; Bannova, K. A.; Kuzmina, N. A.; Zdanova, A. B.

    2016-04-01

    At the present day, a falling in the overall level of efficiency production activities, especially in the machine-building companies makes it necessary to development various actions in the State support, including through the creation consolidated taxation system. Such support will help improve efficiency of activity not only the industrial companies, but also will allow improve economic and social situation in regions where often large engineering factories is city-forming.

  14. How Six Sigma Methodology Improved Doctors' Performance

    Science.gov (United States)

    Zafiropoulos, George

    2015-01-01

    Six Sigma methodology was used in a District General Hospital to assess the effect of the introduction of an educational programme to limit unnecessary admissions. The performance of the doctors involved in the programme was assessed. Ishikawa Fishbone and 5 S's were initially used and Pareto analysis of their findings was performed. The results…

  15. BMI, a performance parameter for speed improvement.

    Directory of Open Access Journals (Sweden)

    Adrien Sedeaud

    Full Text Available The purpose of this study is to investigate the association between anthropometric characteristics and performance in all track and field running events and assess Body Mass Index (BMI as a relevant performance indicator. Data of mass, height, BMI and speed were collected for the top 100 international men athletes in track events from 100 m to marathon for the 1996-2011 seasons, and analyzed by decile of performance. Speed is significantly associated with mass (r = 0.71 and BMI (r = 0.71 in world-class runners and moderately with height (r = 0.39. Athletes, on average were continuously lighter and smaller with distance increments. In track and field, speed continuously increases with BMI. In each event, performances are organized through physique gradients. « Lighter and smaller is better » in endurance events but « heavier and taller is better » for sprints. When performance increases, BMI variability progressively tightens, but it is always centered around a distance-specific optimum. Running speed is organized through biometric gradients, which both drives and are driven by performance optimization. The highest performance level is associated with narrower biometric intervals. Through BMI indicators, diversity is possible for sprints whereas for long distance events, there is a more restrictive aspect in terms of physique. BMI is a relevant indicator, which allows for a clear differentiation of athletes' capacities between each discipline and level of performance in the fields of human possibilities.

  16. BMI, a performance parameter for speed improvement.

    Science.gov (United States)

    Sedeaud, Adrien; Marc, Andy; Marck, Adrien; Dor, Frédéric; Schipman, Julien; Dorsey, Maya; Haida, Amal; Berthelot, Geoffroy; Toussaint, Jean-François

    2014-01-01

    The purpose of this study is to investigate the association between anthropometric characteristics and performance in all track and field running events and assess Body Mass Index (BMI) as a relevant performance indicator. Data of mass, height, BMI and speed were collected for the top 100 international men athletes in track events from 100 m to marathon for the 1996-2011 seasons, and analyzed by decile of performance. Speed is significantly associated with mass (r = 0.71) and BMI (r = 0.71) in world-class runners and moderately with height (r = 0.39). Athletes, on average were continuously lighter and smaller with distance increments. In track and field, speed continuously increases with BMI. In each event, performances are organized through physique gradients. « Lighter and smaller is better » in endurance events but « heavier and taller is better » for sprints. When performance increases, BMI variability progressively tightens, but it is always centered around a distance-specific optimum. Running speed is organized through biometric gradients, which both drives and are driven by performance optimization. The highest performance level is associated with narrower biometric intervals. Through BMI indicators, diversity is possible for sprints whereas for long distance events, there is a more restrictive aspect in terms of physique. BMI is a relevant indicator, which allows for a clear differentiation of athletes' capacities between each discipline and level of performance in the fields of human possibilities.

  17. Using Performance Task Data to Improve Instruction

    Science.gov (United States)

    Abbott, Amy L.; Wren, Douglas G.

    2016-01-01

    Two well-accepted ideas among educators are (a) performance assessment is an effective means of assessing higher-order thinking skills and (b) data-driven instruction planning is a valuable tool for optimizing student learning. This article describes a locally developed performance task (LDPT) designed to measure critical thinking, problem…

  18. Under which conditions does T1 difficulty affect T2 performance in the attentional blink?

    DEFF Research Database (Denmark)

    Nielsen, Simon; Petersen, Anders; Andersen, Tobias

    When two visual targets (T1 & T2) are presented in rapid succession, performance of T2 suffers up to 900 ms. One theory of this attentional blink (Raymond, Shapiro, & Arnell, 1992) propose that T1 and T2 compete for limited processing resources (Chun & Potter, 1995), and predict that prolonging...

  19. Comparison of Physical Fitness Performance between Elementary-Aged Students with and without Attention Deficit Hyperactivity Disorder

    Science.gov (United States)

    Colombo-Dougovito, Andrew M.

    2013-01-01

    The purpose of this investigation was to analyze the possible differences of the physical fitness performance of elementary-aged students with and without attention deficit hyperactivity disorder (ADHD). Little research has been produced in the area of youth with ADHD and motor development; this research paper further investigates the effects of…

  20. The Effects of Highlighting on the Math Computation Performance and Off-Task Behavior of Students with Attention Problems

    Science.gov (United States)

    Kercood, Suneeta; Grskovic, Janice A.

    2009-01-01

    This study evaluated the effects of color highlighting during a math computation task on performance accuracy and behavior of students with attention problems. Using a multiple baseline across participants design, three students solved math computation problems on worksheets with and without highlighting. Off-task behavior recorded from videotape…

  1. Performance Improvement/HPT Model: Guiding the Process

    Science.gov (United States)

    Dessinger, Joan Conway; Moseley, James L.; Van Tiem, Darlene M.

    2012-01-01

    This commentary is part of an ongoing dialogue that began in the October 2011 special issue of "Performance Improvement"--Exploring a Universal Performance Model for HPT: Notes From the Field. The performance improvement/HPT (human performance technology) model represents a unifying process that helps accomplish successful change, create…

  2. Industry activities to improve valve performance

    Energy Technology Data Exchange (ETDEWEB)

    Callaway, C.

    1996-12-01

    Motor-operated valve issues refuse to go away. For over a decade the industry and the NRC have been focusing extraordinary resources on assuring these special components operate when called upon. Now that industry has fixed the design deficiencies, it is focusing on assuring that they perform their safety function within the current licensing basis for the remainder of plant life. NEI supported the efforts by ASME to develop OMN-1 and was encouraged that the industry and the NRC worked together to develop risk and performance based approaches to maintain MOV performance.

  3. Does Advertising Spending Improve Sales Performance?

    DEFF Research Database (Denmark)

    Assaf, A. George; Josiassen, Alexander; Mattila, Anna S.

    2015-01-01

    Hotel managers and investors commonly analyze the impact of advertising spending on firm performance. This paper investigates such an impact using a comprehensive framework incorporating the moderating effects of hotel size and star ratings. We estimated sales performance via dynamic, stochastic...... frontier modelling. Using longitudinal data from a sample of Slovenian and Croatian hotels, we demonstrate that advertising spending has a positive impact on hotel sales performance, and that the relationship strengthens for larger hotels and hotels with higher star ratings. Theoretical and managerial...

  4. Performance appraisal: a tool for practice improvement.

    Science.gov (United States)

    Gesme, Dean H; Wiseman, Marian

    2011-03-01

    Yours may be among the many oncology practices without an appropriate performance review system in place. Lack of an effective evaluation system increases the risk of inefficiency, poor office morale, and high turnover rates.

  5. Performance of Spandex Sector Improves Rapidly

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Zhejiang Huafeng Spandex Co., Ltd.(SZ: 002064) and Sichuan Sofcra Special-Typed Fiber Co., Ltd. (SZ: 000584)as major listed spandex companies in China have recently published their performance statements for the first quarter of 2007.

  6. Improve Compressed Air System Performance with AIRMaster+

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-05-01

    AIRMaster+ provides a systematic apporach for assessing the supply-side performance of compressed air systems. Using plant-specific data, the software effectively evaluates supply-side operational costs for various equipment configurations and system pro

  7. Improving competitiveness through performance-measurement systems.

    Science.gov (United States)

    Stewart, L J; Lockamy, A

    2001-12-01

    Parallels exist between the competitive pressures felt by U.S. manufacturers over the past 30 years and those experienced by healthcare providers today. Increasing market deregulation, changing government policies, and growing consumerism have altered the healthcare arena. Responding to similar pressures, manufacturers adopted a strategic orientation driven by customer needs and expectations that led them to achieve high performance levels and surpass their competition. The adoption of integrated performance-measurement systems was instrumental in these firms' success. An integrated performance-measurement model for healthcare organizations can help to blend the organization's strategy with the demands of the contemporary healthcare environment. Performance-measurement systems encourage healthcare organizations to focus on their mission and vision by aligning their strategic objectives and resource-allocation decisions with customer requirements.

  8. Improving the Performance and Portability of VPIC

    Science.gov (United States)

    Bird, Robert; Peters, Evan; Nystrom, David; Albright, Brian

    2016-10-01

    VPIC is a Particle-in-Cell (PIC) code which is able to deliver novel science at unprecedened scale. Most notably, this includes the attainment of petaflop performance during the simulation of trillions of particles. Such high levels of performance have historically been achieved though the use of vectorization, and explicit compiler intrinsics in VPIC. An approach which can offer good performance, at the cost of the code needing to be re-written for each new vector-width or hardware architecture. In this work we present an investigation of how modern coding techniques and auto-vectorization can be used to enable VPIC to automatically scale to new vector-widths and hardware platforms, using a single codebase which no longer needs to be manually adapted for new vector-widths. To achieve this, we express the core PIC algorithm in such a way that the compiler is able to generate auto-vectorized instructions, including an adaptation of the algorithm so that it no longer contains data dependencies. We also present a performance study for this new code variant, showing that it is able to achieve vector performance comparable to that of historic hand coded intrinsics on both Intel Knights Landing and traditional Intel Xeon platforms. Work performed under the auspices of the U.S. Dept. of Energy by the Los Alamos National Security, LLC Los Alamos National Laboratory under contract DE-AC52-06NA25396 and supported by the LANL LDRD program.

  9. Oculomotor Performance Identifies Underlying Cognitive Deficits in Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Loe, Irene M.; Feldman, Heidi M.; Yasui, Enami; Luna, Beatriz

    2009-01-01

    The evaluation of the cognitive control in children with attention-deficit hyperactivity disorder through the use of oculomotor tests reveal that this group showed susceptibility to peripheral distractors and deficits in response inhibition. All subjects were found to have intact sensorimotor function and working memory.

  10. Independent Oscillatory Patterns Determine Performance Fluctuations in Children with Attention Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Yordanova, Juliana; Albrecht, Bjorn; Uebel, Henrik; Kirov, Roumen; Banaschewski, Tobias; Rothenberger, Aribert; Kolev, Vasil

    2011-01-01

    The maintenance of stable goal-directed behaviour is a hallmark of conscious executive control in humans. Notably, both correct and error human actions may have a subconscious activation-based determination. One possible source of subconscious interference may be the default mode network that, in contrast to attentional network, manifests…

  11. Effects of Tutorial Interventions in Mathematics and Attention for Low-Performing Preschool Children

    Science.gov (United States)

    Barnes, Marcia A.; Klein, Alice; Swank, Paul; Starkey, Prentice; McCandliss, Bruce; Flynn, Kylie; Zucker, Tricia; Huang, Chun-Wei; Fall, Anna-Mária; Roberts, Greg

    2016-01-01

    Two intervention approaches designed to address the multifaceted academic and cognitive difficulties of low-income children who enter pre-K with very low math knowledge were tested in a randomized experiment. Blocking on classroom, children who met screening criteria were assigned to a Math + Attention condition in which the Pre-Kindergarten…

  12. Effects of Methylphenidate (Ritalin) on Auditory Performance in Children with Attention and Auditory Processing Disorders.

    Science.gov (United States)

    Tillery, Kim L.; Katz, Jack; Keller, Warren D.

    2000-01-01

    A double-blind, placebo-controlled study examined effects of methylphenidate (Ritalin) on auditory processing in 32 children with both attention deficit hyperactivity disorder and central auditory processing (CAP) disorder. Analyses revealed that Ritalin did not have a significant effect on any of the central auditory processing measures, although…

  13. Compounds and methods for improving plant performance

    Energy Technology Data Exchange (ETDEWEB)

    Unkefer, Pat J.; Knight, Thomas Joseph

    2016-09-20

    The invention is directed to methods and compositions for increasing a growth characteristic of a plant, increasing nutrient use efficiency of a plant, or improving a plant's ability to overcome stress comprising applying a composition comprising ketosuccinamate, a derivative thereof, or a salt thereof, to the plant or to a propagation material of the plant.

  14. Compounds and methods for improving plant performance

    Science.gov (United States)

    Unkefer, Pat J.; Knight, Thomas Joseph

    2016-09-20

    The invention is directed to methods and compositions for increasing a growth characteristic of a plant, increasing nutrient use efficiency of a plant, or improving a plant's ability to overcome stress comprising applying a composition comprising ketosuccinamate, a derivative thereof, or a salt thereof, to the plant or to a propagation material of the plant.

  15. Improving Student's Lab Practices: the Performance Grade

    CERN Document Server

    Lippi, G L

    2015-01-01

    Instilling good laboratory working attitudes in students is a difficult but very important task, especially in the first level courses. The introduction of a grade, based on the observation of work practices during laboratory sessions, can be strongly beneficial towards the acquisition of positive skills covering not only the technical aspects, but also the acquisition of both independence and team work. Explicit suggestions are given for basing the grade on specific observations and a quantitative analysis is performed to guarantee that the higher intrinsic volatility of the Performance Grade does not affect the final laboratory grade.

  16. Does Negotiation Training Improve Negotiators' Performance?

    Science.gov (United States)

    ElShenawy, Eman

    2010-01-01

    Purpose: This paper's objective is to test the main effect of negotiation training-level on acquiring negotiation skills. Training level refers to the time a trainee spends in a negotiation training course receiving the standard style and methods of training. Negotiation skills are manifested through trainees' performance after receiving training.…

  17. Improving Spelling Performance and Spelling Consciousness

    Science.gov (United States)

    Cordewener, Kim A. H.; Verhoeven, Ludo; Bosman, Anna M. T.

    2016-01-01

    This study examined the immediate and sustained effects of three training conditions on both spelling performance and spelling consciousness of 72 third-grade low- and high-skilled spellers. Spellers were assigned to a strategy-instruction, self-correction, or no-correction condition. The role of spelling ability and word characteristic were also…

  18. Improving spelling performance and spelling consciousness

    NARCIS (Netherlands)

    Cordewener, K.A.H.; Verhoeven, L.T.W.; Bosman, A.M.T.

    2016-01-01

    This study examined the immediate and sustained effects of three training conditions on both spelling performance and spelling consciousness of 72 third-grade low- and high-skilled spellers. Spellers were assigned to a strategy-instruction, self-correction, or no-correction condition. The role of sp

  19. Does Musical Training Improve School Performance?

    Science.gov (United States)

    Wetter, Olive Emil; Koerner, Fritz; Schwaninger, Adrian

    2009-01-01

    In a retrospective study, we compared school performance of 53 children practicing music (group 1) with 67 controls not practicing music (group 2). Overall average marks as well as average marks of all school subjects except sports were significantly higher in children who do (group 1) than in those who do not practice music (group 2). In a…

  20. Improving Oral Performance through Interactions Flashcards

    Science.gov (United States)

    Urquijo, Jasson

    2012-01-01

    This paper describes an action research project that addressed the issue of low oral performance in English among third grade learners at a public girls' school in Bogota, Colombia. The issue was identified via content analysis of ten field logs compiled over the third and fourth quarter of the second semester, 2010. To address the problem of…

  1. Sociodemographic and Individual Predictors of Performance in an Attentional Task with Alert, Orienting and Control Demands in Preschoolers

    Directory of Open Access Journals (Sweden)

    Colombo, Jorge A.

    2012-08-01

    Full Text Available This study explores the predictive value of socioeconomic status, maternal mental health and child temperament on the performance in the attentional network test (ANT, which assesses attentional processes of alert, orienting and control, administered to 203 4-to-5 years-old children (M = 4.78; SD = .59 from Unsatisfied and Satisfied Basic Needs homes (UBN and SBN, respectively. Results from the linear regression analysis indicated that gender, age, effortful control, and marginally parental occupation, predicted increments in reaction times of trials corresponding only to the control network. Predictors were not verified when sociodemographic variables (parental education and occupation, dwelling and overcrowding were replaced in the model by the predictor socioeconomic group (UBN, SBN. These results suggest a differential modulation of individual and environmental factors on different attentional processing networks.

  2. Cognitive performance in visual memory and attention are influenced by many factors

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; Nielsen, Simon

    Visual perception serves as the basis for much of the higher level cognitive processing as well as human activity in general. Here we present normative estimates for the following components of visual perception: the visual perceptual threshold, the visual short-term memory capacity and the visual...... of Visual Attention (TVA). In addition to the estimates themselves, we present correlational data on between the estimates and self-reported demographic data and activities of daily living. The correlates suggests that age, video gaming activity and employment status may significantly impact the encoding...... speed of Visual Short-term Memory (VTSM) but not the capacity of VSTM nor the visual threshold. The estimates will be useful for future studies into the effects of various types of intervention and training on cognition in general and visual attention in particular. (...

  3. Methylphenidate enhances cognitive performance in adults with poor baseline capacities regardless of attention-deficit/hyperactivity disorder diagnosis.

    Science.gov (United States)

    Agay, Nirit; Yechiam, Eldad; Carmel, Ziv; Levkovitz, Yechiel

    2014-04-01

    We compare the view that the effect of methylphenidate (MPH) is selective to individuals with attention-deficit/hyperactivity disorder (ADHD) with an alternative approach suggesting that its effect is more prominent for individuals with weak baseline capacities in relevant cognitive tasks. To evaluate theses 2 approaches, we administered sustained attention, working memory, and decision-making tasks to 20 ADHD adults and 19 control subjects, using a within-subject placebo-controlled design. The results demonstrated no main effects of MPH in the decision-making tasks. In the sustained attention and working-memory tasks, MPH enhanced performance of both ADHD and non-ADHD adults to a similar extent compared with placebo. Hence, the effect of MPH was not selective to ADHD adults. In addition, those benefitting most from MPH in all 3 task domains tended to be individuals with poor task performance. However, in most tasks, individuals whose performance was impaired by MPH were not necessarily better (or worse) performers. The findings suggest that the administration of MPH to adults with ADHD should consider not only clinical diagnosis but also their functional (performance-based) profile.

  4. Brush Seals for Improved Steam Turbine Performance

    Science.gov (United States)

    Turnquist, Norman; Chupp, Ray; Baily, Fred; Burnett, Mark; Rivas, Flor; Bowsher, Aaron; Crudgington, Peter

    2006-01-01

    GE Energy has retrofitted brush seals into more than 19 operating steam turbines. Brush seals offer superior leakage control compared to labyrinth seals, owing to their compliant nature and ability to maintain very tight clearances to the rotating shaft. Seal designs have been established for steam turbines ranging in size from 12 MW to over 1200 MW, including fossil, nuclear, combined-cycle and industrial applications. Steam turbines present unique design challenges that must be addressed to ensure that the potential performance benefits of brush seals are realized. Brush seals can have important effects on the overall turbine system that must be taken into account to assure reliable operation. Subscale rig tests are instrumental to understanding seal behavior under simulated steam-turbine operating conditions, prior to installing brush seals in the field. This presentation discusses the technical challenges of designing brush seals for steam turbines; subscale testing; performance benefits of brush seals; overall system effects; and field applications.

  5. Diversity improves performance in excitable networks

    CERN Document Server

    Gollo, Leonardo L; Roberts, James A

    2016-01-01

    As few real systems comprise indistinguishable units, diversity is a hallmark of nature. Diversity among interacting units shapes properties of collective behavior such as synchronization and information transmission. However, the benefits of diversity on information processing at the edge of a phase transition, ordinarily assumed to emerge from identical elements, remain largely unexplored. Analyzing a general model of excitable systems with heterogeneous excitability, we find that diversity can greatly enhance optimal performance (by two orders of magnitude) when distinguishing incoming inputs. Heterogeneous systems possess a subset of specialized elements whose capability greatly exceeds that of the nonspecialized elements. Nonetheless, the behavior of the whole network can outperform all subgroups. We also find that diversity can yield multiple percolation, with performance optimized at tricriticality. Our results are robust in specific and more realistic neuronal systems comprising a combination of excit...

  6. Improving the Load Balancing Performance of Vlasiator

    CERN Document Server

    Turk, Ata; Demirci, G Vehbi; von Alfthan, Sebastian; Honkonen, Ilja

    2011-01-01

    This whitepaper describes the load-balancing performance issues that are observed and tackled during the petascaling of the Vlasiator codes. Vlasiator is a Vlasov-hybrid simulation code developed in Finnish Meteorological Institute (FMI). Vlasiator models the communications associated with the spatial grid operated on as a hypergraph and partitions the grid using the parallel hypergraph partitioning scheme (PHG) of the Zoltan partitioning framework. The result of partitioning determines the distribution of grid cells to processors. It is observed that the partitioning phase takes a substantial percentage of the overall computation time. Alternative (graph-partitioning-based) schemes that perform almost as well as the hypergraph partitioning scheme and that require less preprocessing overhead and better balance are proposed and investigated. A comparison in terms of effect on running time, preprocessing overhead and load-balancing quality of Zoltan's PHG, ParMeTiS, and PT-SCOTCH are presented. Test results on ...

  7. Improvement of Adaptive Cruise Control Performance

    Directory of Open Access Journals (Sweden)

    Nakagami Takashi

    2010-01-01

    Full Text Available This paper describes the Adaptive Cruise Control system (ACC, a system which reduces the driving burden on the driver. The ACC system primarily supports four driving modes on the road and controls the acceleration and deceleration of the vehicle in order to maintain a set speed or to avoid a crash. This paper proposes more accurate methods of detecting the preceding vehicle by radar while cornering, with consideration for the vehicle sideslip angle, and also of controlling the distance between vehicles. By making full use of the proposed identification logic for preceding vehicles and path estimation logic, an improvement in driving stability was achieved.

  8. Performance improvement in the perioperative system.

    Science.gov (United States)

    Brooks, Kathleen V; Krupka, Dan C

    2012-12-01

    Hospital finance leaders should work with their organizations' perioperative leaders to implement a three-step process for identifying projects with the greatest potential for improving quality while reducing costs and increasing revenue. In essence, this process involves mapping the strategy, developing a list of potential projects, and culling projects that cannot reasonably be accomplished with available resources. The extent to which staff resources are available for such projects can best be measured using a simple spreadsheet designed for tracking special assignments of each staff member.

  9. Neurocognitive functioning in parents of schizophrenia patients: Attentional and executive performance vary with genetic loading.

    Science.gov (United States)

    Schulze-Rauschenbach, Svenja; Lennertz, Leonhard; Ruhrmann, Stephan; Petrovsky, Nadine; Ettinger, Ulrich; Pukrop, Ralf; Dreher, Jan; Klosterkötter, Joachim; Maier, Wolfgang; Wagner, Michael

    2015-12-30

    Neuropsychological deficits are candidate endophenotypes of schizophrenia which can assist to explain the neurocognitive impact of genetic risk variants. The identification of endophenotypes is often based on the familiality of these phenotypes. Several studies demonstrate neuropsychological deficits in unaffected biological relatives of schizophrenia patients without differentiating between genetic and non-genetic factors underlying these deficits. We assessed N=129 unaffected biological parents of schizophrenia patients, N=28 schizophrenia patients (paranoid subtype), and N=143 controls without a family history of schizophrenia with an extensive neuropsychological test battery. Direct comparison of N=22 parents with an ancestral history of schizophrenia (more likely carriers, MLC) and N=17 of their spouses without such a history (less likely carriers, LLC) allowed the separation of genetic and non-genetic aspects in cognition. Overall, parents showed significant deficits in neuropsychological tasks from all cognitive domains with medium effect sizes. Direct comparisons of MLC- and LLC-parents showed that attentional and executive tasks were most strongly affected by genetic loading. To conclude, unaffected parents of schizophrenia patients showed modest yet significant impairments in attention, memory, and executive functioning. In particular, attentional and executive impairments varied most strongly with genetic loading for schizophrenia, prioritising these dysfunctions for genotype-endophenotype analyses.

  10. Sustained multifocal attentional enhancement of stimulus processing in early visual areas predicts tracking performance.

    Science.gov (United States)

    Störmer, Viola S; Winther, Gesche N; Li, Shu-Chen; Andersen, Søren K

    2013-03-20

    Keeping track of multiple moving objects is an essential ability of visual perception. However, the mechanisms underlying this ability are not well understood. We instructed human observers to track five or seven independent randomly moving target objects amid identical nontargets and recorded steady-state visual evoked potentials (SSVEPs) elicited by these stimuli. Visual processing of moving targets, as assessed by SSVEP amplitudes, was continuously facilitated relative to the processing of identical but irrelevant nontargets. The cortical sources of this enhancement were located to areas including early visual cortex V1-V3 and motion-sensitive area MT, suggesting that the sustained multifocal attentional enhancement during multiple object tracking already operates at hierarchically early stages of visual processing. Consistent with this interpretation, the magnitude of attentional facilitation during tracking in a single trial predicted the speed of target identification at the end of the trial. Together, these findings demonstrate that attention can flexibly and dynamically facilitate the processing of multiple independent object locations in early visual areas and thereby allow for tracking of these objects.

  11. Improving Steam System Performance: A Sourcebook for Industry, Second Edition

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-02-23

    This sourcebook is designed to provide steam system users with a reference that describes the basic steam system components, outlines opportunities for energy and performance improvements, and discusses the benefits of a systems approach in identifying and implementing these improvement opportunities. The sourcebook is divided into three main sections: steam system basics, performance improvement opportunities, and where to find help.

  12. Continuing education for performance improvement: a creative approach.

    Science.gov (United States)

    Collins, Patti-Ann; Hardesty, Ilana; White, Julie L; Zisblatt, Lara

    2012-10-01

    In an effort to improve patient safety and health care outcomes, continuing medical education has begun to focus on performance improvement initiatives for physician practices. Boston University School of Medicine's (BUSM) Continuing Nursing Education Accredited Provider Unit has begun a creative project to award nursing contact hours for nurses' participation in performance improvement activities. This column highlights its initial efforts.

  13. Chewing and Attention: A Positive Effect on Sustained Attention

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Hirano

    2015-01-01

    Full Text Available Chewing is crushing food not only to aid swallowing and digestion, but also to help stress relief and regulate cognitive function, especially in attention. It is well known that chewing gum is used for sleepiness prevention during work, learning, and driving, suggesting a link between chewing and sustained attention. We hypothesized that chewing elevates attention and/or alertness, leading to improvements in cognitive performance. We carried out a systematic review of the PubMed database. We inspected the attributes of effects on attention in studies investigating the effects of chewing on attention or alertness conducted with pre-post design in healthy subjects, except elderly. We identified 151 references, 22 of which were included: 14 (64% showed positive attributes of effects on attention, 1 (5% showed negative attributes of effects on attention, 5 (23% showed both positive and negative attributes of effects on attention, and 2 (9% showed no significant attributes of effects on attention. Thus, positive attributes of effects of chewing on attention, especially on sustained attention, were shown in over half of the reports. These effects also appeared with improvement in mood and stress relief and were influenced by time-on-task effect. Further studies are needed, but chewing could be useful for modifying cognitive function.

  14. Chewing and attention: a positive effect on sustained attention.

    Science.gov (United States)

    Hirano, Yoshiyuki; Onozuka, Minoru

    2015-01-01

    Chewing is crushing food not only to aid swallowing and digestion, but also to help stress relief and regulate cognitive function, especially in attention. It is well known that chewing gum is used for sleepiness prevention during work, learning, and driving, suggesting a link between chewing and sustained attention. We hypothesized that chewing elevates attention and/or alertness, leading to improvements in cognitive performance. We carried out a systematic review of the PubMed database. We inspected the attributes of effects on attention in studies investigating the effects of chewing on attention or alertness conducted with pre-post design in healthy subjects, except elderly. We identified 151 references, 22 of which were included: 14 (64%) showed positive attributes of effects on attention, 1 (5%) showed negative attributes of effects on attention, 5 (23%) showed both positive and negative attributes of effects on attention, and 2 (9%) showed no significant attributes of effects on attention. Thus, positive attributes of effects of chewing on attention, especially on sustained attention, were shown in over half of the reports. These effects also appeared with improvement in mood and stress relief and were influenced by time-on-task effect. Further studies are needed, but chewing could be useful for modifying cognitive function.

  15. Directed evolution strategies for improved enzymatic performance

    Directory of Open Access Journals (Sweden)

    Dalby Paul A

    2005-10-01

    Full Text Available Abstract The engineering of enzymes with altered activity, specificity and stability, using directed evolution techniques that mimic evolution on a laboratory timescale, is now well established. However, the general acceptance of these methods as a route to new biocatalysts for organic synthesis requires further improvement of the methods for both ease-of-use and also for obtaining more significant changes in enzyme properties than is currently possible. Recent advances in library design, and methods of random mutagenesis, combined with new screening and selection tools, continue to push forward the potential of directed evolution. For example, protein engineers are now beginning to apply the vast body of knowledge and understanding of protein structure and function, to the design of focussed directed evolution libraries, with striking results compared to the previously favoured random mutagenesis and recombination of entire genes. Significant progress in computational design techniques which mimic the experimental process of library screening is also now enabling searches of much greater regions of sequence-space for those catalytic reactions that are broadly understood and, therefore, possible to model. Biocatalysis for organic synthesis frequently makes use of whole-cells, in addition to isolated enzymes, either for a single reaction or for transformations via entire metabolic pathways. As many new whole-cell biocatalysts are being developed by metabolic engineering, the potential of directed evolution to improve these initial designs is also beginning to be realised.

  16. Attentional Performance in Children and Adolescents with Tic Disorder and Co-Occurring Attention-Deficit/hyperactivity Disorder: New Insights from a 2 x 2 Factorial Design Study

    Science.gov (United States)

    Greimel, Ellen; Wanderer, Sina; Rothenberger, Aribert; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Roessner, Veit

    2011-01-01

    The aim of the present study was to investigate the effect of both tic disorder (TD) and attention-deficit/hyperactivity disorder (ADHD) on attentional functions. N = 96 children and adolescents participated in the study, including n = 21 subjects with TD, n = 23 subjects with ADHD, n = 25 subjects with TD+ADHD, and n = 27 controls. Attentional…

  17. Virtual-reality-based attention assessment of ADHD: ClinicaVR: Classroom-CPT versus a traditional continuous performance test.

    Science.gov (United States)

    Neguț, Alexandra; Jurma, Anda Maria; David, Daniel

    2016-06-03

    Virtual-reality-based assessment may be a good alternative to classical or computerized neuropsychological assessment due to increased ecological validity. ClinicaVR: Classroom-CPT (VC) is a neuropsychological test embedded in virtual reality that is designed to assess attention deficits in children with attention deficit hyperactivity disorder (ADHD) or other conditions associated with impaired attention. The present study aimed to (1) investigate the diagnostic validity of VC in comparison to a traditional continuous performance test (CPT), (2) explore the task difficulty of VC, (3) address the effect of distractors on the performance of ADHD participants and typically-developing (TD) controls, and (4) compare the two measures on cognitive absorption. A total of 33 children diagnosed with ADHD and 42 TD children, aged between 7 and 13 years, participated in the study and were tested with a traditional CPT or with VC, along with several cognitive measures and an adapted version of the Cognitive Absorption Scale. A mixed multivariate analysis of covariance (MANCOVA) revealed that the children with ADHD performed worse on correct responses had more commissions and omissions errors than the TD children, as well as slower target reaction times . The results showed significant differences between performance in the virtual environment and the traditional computerized one, with longer reaction times in virtual reality. The data analysis highlighted the negative influence of auditory distractors on attention performance in the case of the children with ADHD, but not for the TD children. Finally, the two measures did not differ on the cognitive absorption perceived by the children.

  18. Mindfulness training affects attention--or is it attentional effort?

    DEFF Research Database (Denmark)

    Jensen, Christian Gaden; Vangkilde, Signe Allerup; Frokjaer, Vibe

    2012-01-01

    and visual working memory capacity. Furthermore, stress-reducing effects of MBSR were supported because those in the MBSR group showed significantly less perceived and physiological stress while increasing their mindfulness levels significantly. We argue that MBSR may contribute uniquely to attentional......Improvements in attentional performance are at the core of proposed mechanisms for stress reduction in mindfulness meditation practices. However, this claim can be questioned because no previous studies have actively manipulated test effort in control groups and controlled for effects of stress......, the latter receiving a financial reward to improve attentional performance. Pre- and postintervention, 5 validated attention paradigms were employed along with self-report scales on mindfulness and perceived stress and saliva cortisol samples to measure physiological stress. Attentional effects of MBSR, NMSR...

  19. Performance improvement of CGHs for optical testing

    Science.gov (United States)

    Pruss, Christof; Reichelt, Stephan; Korolkov, Victor P.; Osten, Wolfgang; Tiziani, Hans J.

    2003-05-01

    The expansion of the field of diffractive optics applications is accompanied by toughening performance requirements for CGHs. Optical testing sets especially high requirements, concerning wavefront accuracy and diffraction efficiency. The key point in fabrication technology is the writing system creating the photomask or the profiled pattern. The diffractive optics fabrication facility at ITO (University of Stuttgart) is based on the circular laser writing system CLWS-300. This flexible and high-accurate tool was originally designed for binary diffractive optics fabrication. This paper presents novel enhancements of this system allowing direct laser writing of a wide range of binary and continuous-relief CGHs on photoresist layers, chromium films and LDW-glass. Main topics of the enhancements were the scanning accuracy and exposure control. Many types of CGHs (binary precision holograms for optical testing, Shack-Hartmann arrays, microlens discs for confocal microscopy, diffractive interferometer objectives, doughnut generators etc.) have been manufactured using the developed algorithms and hardware.

  20. Improving the Gas Instantaneous Water Heaters Performances

    Directory of Open Access Journals (Sweden)

    Nasir Kloub

    2005-01-01

    Full Text Available This study presents a study of a theoretical and practical investigation of the gas Instantaneous (Tankless water Heaters performance. The results allow us to obtain realistic values of the control system in the various capacities gaseous flowing water heaters. The objective of this work is to study the operation of the plans in the field of controlling and checking low capacity gaseous flowing water in order to choose the proper plan of the logical values and measures for these equipments that may be used in industrial conditions. Also results of the work proved to be accurate. A design of the control system was made. The results of the practical experiment of the control system were similar to the arithmetic results.

  1. Improving neural network performance on SIMD architectures

    Science.gov (United States)

    Limonova, Elena; Ilin, Dmitry; Nikolaev, Dmitry

    2015-12-01

    Neural network calculations for the image recognition problems can be very time consuming. In this paper we propose three methods of increasing neural network performance on SIMD architectures. The usage of SIMD extensions is a way to speed up neural network processing available for a number of modern CPUs. In our experiments, we use ARM NEON as SIMD architecture example. The first method deals with half float data type for matrix computations. The second method describes fixed-point data type for the same purpose. The third method considers vectorized activation functions implementation. For each method we set up a series of experiments for convolutional and fully connected networks designed for image recognition task.

  2. Improving video processing performance using temporal reasoning

    Science.gov (United States)

    Ahmed, Mohamed; Karmouch, Ahmed

    1999-10-01

    In this paper, we present a system, called MediABS, for extracting key frames in a video segment. First we will describe the overall architecture of the system and we will show how our system can handle multiple video formats with a single video-processing module. Then we will present a new algorithm, based on color histograms. The algorithm exploits the temporal characteristic of the visual information and provides techniques for avoiding false cuts and eliminating the possibility of missing true cuts. A discussion, along with some results, will be provided to show the merits of our algorithm compared to existing related algorithms. Finally we will discuss the performance (in terms of processing time and accuracy) obtained by our system in extracting the key frames from a video segment. This work is part of the Mobile Agents Alliance project involving University of Ottawa, National Research Council (NRC) and Mitel Corporation.

  3. Improving the Performance of Urban Road Intersection.

    Directory of Open Access Journals (Sweden)

    Dr. Fareed M.A.Karim

    2014-03-01

    Full Text Available Road intersection is responsible for an important proportion of air pollution especially in urban areas, due to long queues of vehicles waiting for discharge. Therefore, it is necessary to quantify their emissions as accurately as possible. In this study an attempt was made to research on reducing the traffic air pollution such as CO, CO2, HC and NOx, fuel consumption and vehicle operating cost along with improving the traffic flow and delay at a road intersection. One major uncontrolled (un signalized intersection in capital city Sana'a (Yemen was chosen for the study. The traffic air pollution, fuel consumption and vehicle operating cost as well as vehicle delay was calculated for the base year 2012 using aaSIDRA 2.0 software developed in Australia. For the horizon year 2022, three scenarios were considered for investigation viz. (1 do nothing, (2 signalizing the intersection and (3 construction of flyover. The analysis shows that for the above mentioned parameters scenario (3 will be the best scenario followed by scenario (2, while worst case scenario will be do nothing.

  4. Progenitor cell release plus exercise to improve functional performance in peripheral artery disease: the PROPEL Study.

    Science.gov (United States)

    Domanchuk, Kathryn; Ferrucci, Luigi; Guralnik, Jack M; Criqui, Michael H; Tian, Lu; Liu, Kiang; Losordo, Douglas; Stein, James; Green, David; Kibbe, Melina; Zhao, Lihui; Annex, Brian; Perlman, Harris; Lloyd-Jones, Donald; Pearce, William; Taylor, Doris; McDermott, Mary M

    2013-11-01

    Functional impairment, functional decline, and mobility loss are major public health problems in people with lower extremity peripheral artery disease (PAD). Few medical therapies significantly improve walking performance in PAD. We describe methods for the PROgenitor cell release Plus Exercise to improve functionaL performance in PAD (PROPEL) Study, a randomized controlled clinical trial designed to determine whether granulocyte-macrophage colony stimulating factor (GM-CSF) combined with supervised treadmill walking exercise improves six-minute walk distance more than GM-CSF alone, more than supervised treadmill exercise alone, and more than placebo plus attention control in participants with PAD, respectively. PROPEL Study participants are randomized to one of four arms in a 2 by 2 factorial design. The four study arms are GM-CSF plus supervised treadmill exercise, GM-CSF plus attention control, placebo plus supervised exercise therapy, or placebo plus attention control. The primary outcome is change in six-minute walk distance at 12-week follow-up. Secondary outcomes include change in brachial artery flow-mediated dilation (FMD), change in maximal treadmill walking time, and change in circulating CD34+ cells at 12-week follow-up. Outcomes are also measured at six-week and six-month follow-up. Results of the PROPEL Study will have important implications for understanding mechanisms of improving walking performance and preventing mobility loss in the large and growing number of men and women with PAD.

  5. Attention to Attention

    DEFF Research Database (Denmark)

    Tække, Jesper; Paulsen, Michael Eric

    In these years digital media and wireless networks are introduced in upper secondary schools in Denmark. This implies new “attentional objects” like updates on Facebook or tweets on Twitter within instant reach of the pupils and teachers. Also it implies new kinds of attention (awareness) like wh...

  6. 有限关注与股票市场表现%Limited Attention and Stock Market Performance

    Institute of Scientific and Technical Information of China (English)

    汤祥凤

    2016-01-01

    本文选取股票代码日百度指数作为投资者关注度的衡量指标,实证分析了投资者有限关注与个股市场表现之间的关系。结果显示:投资者的关注会对个股交易量、换手率等市场交易指标带来正的影响;进一步,投资者的关注会造成股票当期收益的溢价,其滞后期则出现反转效应。%Selecting stock code-baidu index as a measure of investors’ attention, the author empirical analyzed the relationship between the investors’ limited attention and individual stock performance. The results showed that investors’ attention to stock market indexes such as volume, turnover rate brings positive effect; Furthermore, investors ’ attention will cause current stock earnings premium while its lag period generated reversal effect.

  7. Intellectual performance and school failure in children with attention deficit hyperactivity disorder and in their siblings.

    Science.gov (United States)

    Faraone, S V; Biederman, J; Lehman, B K; Spencer, T; Norman, D; Seidman, L J; Kraus, I; Perrin, J; Chen, W J; Tsuang, M T

    1993-11-01

    We made psychiatric and intellectual assessments of 140 children with attention deficit hyperactivity disorder (ADHD), 120 normal controls, and their 303 siblings. The index children were white, non-Hispanic boys. ADHD children were more likely to have had learning disabilities, repeated grades, been placed in special classes, and received academic tutoring. They also did worse on the Wechsler Intelligence Scale for Children--Revised (WISC-R). Among ADHD probands, comorbid conduct, major depressive, and anxiety disorders predicted school placement more than school failure or WISC-R scores. However, the neuropsychological disability of all ADHD children could not be attributed to comorbid disorders because those without comorbidity had more school failure and lower WISC-R scores than normal controls. Intellectual impairment was also increased among siblings of ADHD children. This provides converging evidence that the ADHD syndrome is familial.

  8. Complex Heat Exchangers for Improved Performance

    Science.gov (United States)

    Bran, Gabriela Alejandra

    propagates along the channel. However, the sinusoidal behavior on one of the fluids does not fully translate to the other gets damped by the wall and the heat transfer coefficients that can be barely seen on the other flow. A scaling analysis and a parametric study were performed to determine the influence the different parameters on the system have on the time a heat exchanger takes to reach steady state. The results show the dependency of tst* (time a system takes to reach steady state) on the dimensionless parameters M, C, NTUh, NTUc, and Cw. t st* depends linearly on C and Cw, and it is a power function of M. It was also shown that tst* has a logarithmic dependency on NTUh and NTUc. A correlation was generated to approximate the time a system takes to reach steady state for systems where C w system is the start-up time and also how disturbances in reacting flow can affect the steam outlet temperature. The transient behavior during the system start-up was presented. In order to achieve the desired outlet steam temperature at a reasonable time, the system must operate at high gas mass flow rates. If the inlet temperature of the gas suffers a step change, it affects the reaction rate as well as the outlet steam temperature. A small perturbation on the gas mass flow rate has an effect on the profile shape. However, the maximum temperature reached by the gas due to reaction is not affected, and consequently, it has little effect on the steam temperature. Axial conduction in the reactor heat exchanger was also investigated, specifically in the gas section. Axial conduction cannot be assumed to be negligible in the reactor heat exchanger because of the iron-based catalytic bed. Results in this section show that axial conduction is detrimental for the system. It was found that for Peclet number greater than 100, axial conduction can be neglected. An alternative solution to address axial conduction was proposed, namely to include a well-insulated non-reacting section (without a

  9. Balancing act. Using the clinic scorecard to improve practice performance.

    Science.gov (United States)

    Scanlan, Art

    2007-02-01

    The balanced scorecard is a strategic management system that impels managers to focus on the performance metrics that drive success. It measures the business process and links a management method for process improvement to strategic goals. A medical practice can use a balanced scorecard to improve operational performance and quality or service, which generates higher levels of patient satisfaction and better financial management.

  10. Glucocorticoids improve high-intensity exercise performance in humans

    DEFF Research Database (Denmark)

    Casuso, Rafael A; Melskens, Lars; Bruhn, Thomas;

    2014-01-01

    It was investigated whether oral dexamethasone (DEX) administration improves exercise performance by reducing the initial rate of muscle fatigue development during dynamic exercise.......It was investigated whether oral dexamethasone (DEX) administration improves exercise performance by reducing the initial rate of muscle fatigue development during dynamic exercise....

  11. Sustained attention, attentional selectivity, and attentional capacity across the lifespan.

    Science.gov (United States)

    McAvinue, Laura P; Habekost, Thomas; Johnson, Katherine A; Kyllingsbæk, Søren; Vangkilde, Signe; Bundesen, Claus; Robertson, Ian H

    2012-11-01

    Changes in sustained attention, attentional selectivity, and attentional capacity were examined in a sample of 113 participants between the ages of 12 and 75. To measure sustained attention, we employed the sustained-attention-to-response task (Robertson, Manly, Andrade, Baddeley, & Yiend, Neuropsychologia 35:747-58, 1997), a short continuous-performance test designed to capture fluctuations in sustained attention. To measure attentional selectivity and capacity, we employed a paradigm based on the theory of visual attention (Bundesen, Psychological Review 97:523-547, 1990), which enabled the estimation of parameters related to attentional selection, perceptual threshold, visual short-term memory capacity, and processing capacity. We found evidence of age-related decline in each of the measured variables, but the declines varied markedly in terms of magnitude and lifespan trajectory. Variables relating to attentional capacity showed declines of very large effect sizes, while variables relating to attentional selectivity and sustained attention showed declines of medium to large effect sizes, suggesting that attentional control is relatively preserved in older adults. The variables relating to sustained attention followed a U-shaped, curvilinear trend, and the variables relating to attentional selectivity and capacity showed linear decline from early adulthood, providing further support for the differentiation of attentional functions.

  12. A trial-by-trial analysis reveals more intense physical activity is associated with better cognitive control performance in attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Hartanto, T A; Krafft, C E; Iosif, A M; Schweitzer, J B

    2016-01-01

    Hyperactivity is a key symptom and the most observable manifestation of attention-deficit/hyperactivity disorder (ADHD). The over-activity associated with ADHD can cause specific challenges in academic settings, extracurricular activities and social relationships. Cognitive control challenges are also well established in ADHD. The current study included 44 children between the ages of 10 and 17 diagnosed with ADHD or who were typically developing (TD), all of whom had no psychiatric co-morbidity or significant learning disorders. Participants wore an actometer on their ankle while performing a flanker paradigm in order to objectively measure their rates of activity in association with cognitive control. Analyses assessed the relationship between frequency and intensity of activity to task accuracy on a trial-by-trial basis. A significant interaction effect between group and performance revealed that more intense movement was associated with better performance in the ADHD group but not in the TD group. The ADHD group demonstrated more intense activity than the TD group during correct (but not error) trials. Within-group, children with ADHD generated higher intensity movements in their correct trials compared to their error trials, whereas the TD group did not demonstrate any within-group differences. These findings suggest that excessive motoric activity associated with clinically significant ADHD symptoms may reflect compensatory efforts to modulate attention and alertness. Future research should systematically explore the relationship between motion in ADHD and how it might be used to improve cognitive performance.

  13. Measurement of Overall Performance Effectiveness in Setup Improvement

    Directory of Open Access Journals (Sweden)

    Shye-Nee Low

    2014-01-01

    Full Text Available This study aimed to improve the setup process of injection molding machines by using the developed setup improvement methodology. Overall performance effectiveness (OPE was used to evaluate the setup improvement. A case study was tested on the application of the developed setup improvement methodology. A 50.1% reduction in setup time was attained by the developed methodology, and significant time savings were achieved with minimum investment. Comparisons between before and after improvement implementation were conducted through OPE to verify the improvement. In terms of OPE, the setup performance in the case study considered an acceptable value of 60.45%. The setup process performance of the developed setup improvement methodology was judged in terms of effectiveness. Results therefore indicate that OPE measurement is an effective way to analyze the efficiency of a single setup process.

  14. Patterns and predictors of adolescent academic achievement and performance in a sample of children with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Langberg, Joshua M; Molina, Brooke S G; Arnold, L Eugene; Epstein, Jeffery N; Altaye, Mekibib; Hinshaw, Stephen P; Swanson, James M; Wigal, Timothy; Hechtman, Lily

    2011-01-01

    The current study examined predictors of academic achievement, measured by standardized test scores, and performance, measured by school grades, in adolescents (Mn age = 16.8) who met diagnostic criteria for Attention-Deficit/Hyperactivity Disorder (ADHD)-Combined type in early childhood (Mn age = 8.5; N = 579). Several mediation models were also tested to determine whether ADHD medication use, receipt of special education services, classroom performance, homework completion, or homework management mediated the relationship between symptoms of ADHD and academic outcomes. Childhood predictors of adolescent achievement differed from those for performance. Classroom performance and homework management mediated the relationship between symptoms of inattention and academic outcomes.

  15. Attention-Deficit Hyperactivity Disorder Status and Baseline Neurocognitive Performance in High School Athletes.

    Science.gov (United States)

    Salinas, Christine M; Dean, Preston; LoGalbo, Anthony; Dougherty, Michael; Field, Melvin; Webbe, Frank M

    2016-01-01

    Approximately 136,000 concussions occur annually in American high school sports. Neuropsychological data indicate that children with preexisting cognitive difficulties, such as attention-deficit hyperactivity disorder (ADHD), may have protracted recovery from concussion. ADHD, with an estimated prevalence of 11% in youth, may increase an athlete's vulnerability to sustaining sports-related traumatic brain injury (TBI). The preponderance of evidence focusing on TBI and ADHD has derived from motor vehicle accidents rather than sports-related incidents. Thus, it is paramount to explore how ADHD may relate to injury in the sports concussion context, as well as to assess how ADHD may affect baseline neurocognitive testing. Adolescent athletes with ADHD (n = 256) demonstrated significantly reduced Verbal Memory, Visual Motor, and Impulse Control index scores compared with their peers without ADHD (n = 256). Athletes with ADHD were nearly twice as likely to have sustained a prior concussion (ADHD, 14.1%; non-ADHD, 7.8%). Knowledge regarding the unique neurocognitive profile of athletes with ADHD may enhance clinical management decisions.

  16. Long-term average performance benefits of parabolic trough improvements

    Energy Technology Data Exchange (ETDEWEB)

    Gee, R.; Gaul, H.W.; Kearney, D.; Rabl, A.

    1980-03-01

    Improved parabolic trough concentrating collectors will result from better design, improved fabrication techniques, and the development and utilization of improved materials. The difficulty of achieving these improvements varies as does their potential for increasing parabolic trough performance. The purpose of this analysis is to quantify the relative merit of various technology advancements in improving the long-term average performance of parabolic trough concentrating collectors. The performance benefits of improvements are determined as a function of operating temperature for north-south, east-west, and polar mounted parabolic troughs. The results are presented graphically to allow a quick determination of the performance merits of particular improvements. Substantial annual energy gains are shown to be attainable. Of the improvements evaluated, the development of stable back-silvered glass reflective surfaces offers the largest performance gain for operating temperatures below 150/sup 0/C. Above 150/sup 0/C, the development of trough receivers that can maintain a vacuum is the most significant potential improvement. The reduction of concentrator slope errors also has a substantial performance benefit at high operating temperatures.

  17. Spelling performance of students with developmental dyslexia and with developmental dyslexia associated to attention deficit disorder and hyperactivity.

    Science.gov (United States)

    Alves, Débora Cristina; Casella, Erasmo Barbante; Ferraro, Alexandre Arcanjo

    2016-04-01

    Purpose to analyze and classify the spelling performance according to the semiology of spelling error of children with developmental dyslexia (DD) and with developmental dyslexia associated to attention deficit disorder and hyperactivity(DD and ADHD) comparing them to a group of children without learning process complaints. Methods Seventy students, from the third to fifth grade, participated in this study divided as follows: 32 children without complaints of learning difficulties (GI), mean age 9.5 years; 22 students with developmental dyslexia (GII), mean age 10 years; 16 scholars with developmental dyslexia associated to attention deficit disorders and hyperactivity (GIII), mean age 9.9. Spelling skills were assessed through a standardized word dictation task. Results Data indicated that GII and GIII children presented lower performance when compared with typically developed children. There was no statistical difference between the performance of GII and GIII children regarding the score reached in spelling, although GIII children presented the lowest performance. We observed differences between GII and GIII only in the type of misspelling. Conclusion Data from this research contribute to develop better programs for intervention in the studied population.

  18. Effects of Process and Human Performance Improvement Strategies

    Science.gov (United States)

    Sasson, Joseph R.; Alvero, Alicia M.; Austin, John

    2006-01-01

    Organizational performance is a function of many variables, two of which are work process factors and human performance factors. Our study compared the effects of changing a work process versus human performance improvement techniques and the combined effects of combing both techniques. A 2 (manual vs electronic process) x 2 (with vs without…

  19. Moral concerns increase attention and response monitoring during IAT performance : ERP evidence

    NARCIS (Netherlands)

    van Nunspeet, Félice; Ellemers, Naomi; Derks, Belle; Nieuwenhuis, Sander

    2014-01-01

    Previous research has revealed that people value morality as a more important person characteristic than competence. In this study, we tested whether people adjust their less explicit behavior more to moral than competence values. Participants performed an Implicit Association Test (IAT) that was ei

  20. Flashing characters with famous faces improves ERP-based brain-computer interface performance

    Science.gov (United States)

    Kaufmann, T.; Schulz, S. M.; Grünzinger, C.; Kübler, A.

    2011-10-01

    Currently, the event-related potential (ERP)-based spelling device, often referred to as P300-Speller, is the most commonly used brain-computer interface (BCI) for enhancing communication of patients with impaired speech or motor function. Among numerous improvements, a most central feature has received little attention, namely optimizing the stimulus used for eliciting ERPs. Therefore we compared P300-Speller performance with the standard stimulus (flashing characters) against performance with stimuli known for eliciting particularly strong ERPs due to their psychological salience, i.e. flashing familiar faces transparently superimposed on characters. Our results not only indicate remarkably increased ERPs in response to familiar faces but also improved P300-Speller performance due to a significant reduction of stimulus sequences needed for correct character classification. These findings demonstrate a promising new approach for improving the speed and thus fluency of BCI-enhanced communication with the widely used P300-Speller.

  1. Chronic cannabis use and ERP correlates of visual selective attention during the performance of a flanker go/nogo task.

    Science.gov (United States)

    Nicholls, Clare; Bruno, Raimondo; Matthews, Allison

    2015-09-01

    The aim of the study was to investigate the relationship between chronic cannabis use and visual selective attention by examining event-related potentials (ERPs) during the performance of a flanker go/nogo task. Male participants were 15 chronic cannabis users (minimum two years use, at least once per week) and 15 drug naive controls. Cannabis users showed longer reaction times compared to controls with equivalent accuracy. Cannabis users also showed a reduction in the N2 'nogo effect' at frontal sites, particularly for incongruent stimuli, and particularly in the right hemisphere. This suggests differences between chronic cannabis users and controls in terms of inhibitory processing within the executive control network, and may implicate the right inferior frontal cortex. There was also preliminary evidence for differences in early selective attention, with controls but not cannabis users showing modulation of N1 amplitude by flanker congruency. Further investigation is required to examine the potential reversibility of these residual effects after long-term abstinence and to examine the role of early selective attention mechanisms in more detail.

  2. The Effect of Animal-assisted Play Therapy (AAT) on Improving the Life Quality of Parents having Children with ADHD (Attention Deficit Hyperactivity Disorder in children) Treated with Methylphenidate

    OpenAIRE

    Nazila Motarabesoun; Seyed Mahmoud Tabatabaei

    2016-01-01

    Background and purpose: ADHD (Attention Deficit Hyperactivity Disorder in children) is considered to be one of the most widespread neuro-behavioral disorders in children, which is typically characterized by problems such as poor educational performance, communication difficulties and other social inconsistencies. Timely identification and treatment of this disorder can result in significant improvement in their individual and social performances and it can reduce the symptoms of this disorder...

  3. Neurofeedback as an Intervention to Improve Reading Achievement in Students with Attention- Deficit/Hyperactivity Disorder, Inattentive Subtype

    Science.gov (United States)

    La Marca, Jeffry P.; O'Connor, Rollanda E.

    2016-01-01

    Research consistently demonstrates that attention deficits have a deleterious effect on academic achievement. Impairments in attention, and not hyperactivity/impulsivity, are associated with learning difficulties and academic problems in students with attention-deficit/hyperactivity disorder (ADHD). To date, most studies have focused on symptoms…

  4. Does long-term medication use improve the academic outcomes of youth with attention-deficit/hyperactivity disorder?

    Science.gov (United States)

    Langberg, Joshua M; Becker, Stephen P

    2012-09-01

    Youth with Attention-Deficit/Hyperactivity Disorder (ADHD) frequently experience academic impairment, including lower grades than their peers and elevated risk for grade retention and school dropout. Medication is the most commonly used treatment for youth with ADHD, and it is therefore essential to understand the extent to which medication use improves long-term academic functioning. This paper reviews the literature on the relation between long-term medication use and the academic outcomes of youth with ADHD. A systematic literature search was conducted to identify pertinent studies published since 2000 that followed youth with ADHD for 3 or more years. Academic outcomes of interest included school grades, achievement test scores, and grade retention. Nine studies were identified reporting on eight distinct longitudinal samples (N across studies = 8,721). These studies demonstrate that long-term medication use is associated with improvements in standardized achievement scores. However, the magnitude of these improvements is small and the clinical or educational significance is questionable. Evidence for long-term improvements in school grades and grade retention is less compelling. This review highlights methodological considerations in providing directions for future research. The importance of using multiple sources to gather information about medication adherence is discussed, including use of methodologies such as electronic monitors, rather than relying solely on parent report or chart review. Future research should also examine a range of medication adherence definitions in order to determine whether age of onset, duration of use, dose, and/or consistency of use moderates the relation between long-term medication use and academic outcomes.

  5. Improving Fan System Performance: A Sourcebook for Industry

    Energy Technology Data Exchange (ETDEWEB)

    None

    2003-04-01

    This is one of a series of sourcebooks on motor-driven equipment produced by the Industrial Technologies Program. It provides a reference for industrial fan systems users, outlining opportunities to improve fan system performance.

  6. Monitoring cholinergic activity during attentional performance in mice heterozygous for the choline transporter: a model of cholinergic capacity limits.

    Science.gov (United States)

    Paolone, Giovanna; Mallory, Caitlin S; Koshy Cherian, Ajeesh; Miller, Thomas R; Blakely, Randy D; Sarter, Martin

    2013-12-01

    Reductions in the capacity of the human choline transporter (SLC5A7, CHT) have been hypothesized to diminish cortical cholinergic neurotransmission, leading to risk for cognitive and mood disorders. To determine the acetylcholine (ACh) release capacity of cortical cholinergic projections in a mouse model of cholinergic hypofunction, the CHT+/- mouse, we assessed extracellular ACh levels while mice performed an operant sustained attention task (SAT). We found that whereas SAT-performance-associated increases in extracellular ACh levels of CHT+/- mice were significantly attenuated relative to wildtype littermates, performance on the SAT was normal. Tetrodotoxin-induced blockade of neuronal excitability reduced both dialysate ACh levels and SAT performance similarly in both genotypes. Likewise, lesions of cholinergic neurons abolished SAT performance in both genotypes. However, cholinergic activation remained more vulnerable to the reverse-dialyzed muscarinic antagonist atropine in CHT+/- mice. Additionally, CHT+/- mice displayed greater SAT-disrupting effects of reverse dialysis of the nAChR antagonist mecamylamine. Receptor binding assays revealed a higher density of α4β2* nAChRs in the cortex of CHT+/- mice compared to controls. These findings reveal compensatory mechanisms that, in the context of moderate cognitive challenges, can overcome the performance deficits expected from the significantly reduced ACh capacity of CHT+/- cholinergic terminals. Further analyses of molecular and functional compensations in the CHT+/- model may provide insights into both risk and resiliency factors involved in cognitive and mood disorders.

  7. Performance improvement of silicon solar cells by nanoporous silicon coating

    Directory of Open Access Journals (Sweden)

    Dzhafarov T. D.

    2012-04-01

    Full Text Available In the present paper the method is shown to improve the photovoltaic parameters of screen-printed silicon solar cells by nanoporous silicon film formation on the frontal surface of the cell using the electrochemical etching. The possible mechanisms responsible for observed improvement of silicon solar cell performance are discussed.

  8. The effect of methylphenidate on sustained attention among adolescents with attention-deficit hyperactivity disorder.

    Science.gov (United States)

    Lufi, Dubi; Bassin-Savion, Shiry; Rubel, Lilach

    2015-01-01

    Twenty-seven adolescents diagnosed as having attention-deficit hyperactivity disorder (ADHD) were tested twice with a computerized MATH-CPT (mathematics continuous performance test). In one administration, the participants took medication (methylphenidate, MPH) 1.5 hr before being tested. In another administration, the MATH-CPT was administered without the medication. Treatment with MPH improved the "overall attention level" and in measures of "reaction time" and "impulsivity." MPH did not improve the performance in the four measures of sustained attention. Knowing that treatment with MPH does not improve sustained attention can be helpful in reaching a decision of whether or not a child should be treated with MPH.

  9. Environmental heat stress enhances mental fatigue during sustained attention task performing: evidence from an ASL perfusion study.

    Science.gov (United States)

    Qian, Shaowen; Li, Min; Li, Guoying; Liu, Kai; Li, Bo; Jiang, Qingjun; Li, Li; Yang, Zhen; Sun, Gang

    2015-03-01

    This study was to investigate the potential enhancing effect of heat stress on mental fatigue progression during sustained attention task using arterial spin labeling (ASL) imaging. Twenty participants underwent two thermal exposures in an environmental chamber: normothermic (NT) condition (25°C, 1h) and hyperthermic (HT) condition (50°C, 1h). After thermal exposure, they performed a twenty-minute psychomotor vigilance test (PVT) in the scanner. Behavioral analysis revealed progressively increasing subjective fatigue ratings and reaction time as PVT progressed. Moreover, heat stress caused worse performance. Perfusion imaging analyses showed significant resting-state cerebral blood flow (CBF) alterations after heat exposure. Specifically, increased CBF mainly gathered in thalamic-brainstem area while decreased CBF predominantly located in fronto-parietal areas, anterior cingulate cortex, posterior cingulate cortex, and medial frontal cortex. More importantly, diverse CBF distributions and trend of changes between both conditions were observed as the fatigue level progressed during subsequent PVT task. Specifically, higher CBF and enhanced rising trend were presented in superior parietal lobe, precuneus, posterior cingulate cortex and anterior cingulate cortex, while lower CBF or inhibited rising trend was found in dorsolateral frontal cortex, medial frontal cortex, inferior parietal lobe and thalamic-brainstem areas. Furthermore, the decrease of post-heat resting-state CBF in fronto-parietal cortex was correlated with subsequent slower reaction time, suggesting prior disturbed resting-state CBF might be indicator of performance potential and fatigue level in following task. These findings may provide proof for such a view: heat stress has a potential fatigue-enhancing effect when individual is performing highly cognition-demanding attention task.

  10. Impaired Memory for Instructions in Children with Attention-Deficit Hyperactivity Disorder Is Improved by Action at Presentation and Recall.

    Science.gov (United States)

    Yang, Tian-Xiao; Allen, Richard J; Holmes, Joni; Chan, Raymond C K

    2017-01-01

    Children with attention deficit hyperactivity disorder (ADHD) often fail to comply with teacher instructions in the classroom. Using action during presentation or recall can enhance typically developing children's abilities to complete multi-step instruction sequences. In this study, we tested the ability to following instructions in children with ADHD under different conditions to explore whether they show the same beneficial effects of action. A total of 24 children with ADHD and 27 typically developing children either listened to or viewed demonstrations of instructions during encoding, and then either verbally repeated or physically performed the sequences during recall. This resulted in four conditions: spoken-verbal, spoken-enacted, demonstration-verbal, and demonstration-enacted. Children with ADHD were significantly impaired in all conditions of the following instructions task relative to the typically developing group. Both groups showed an enacted-recall advantage, with superior recall by physical performance than oral repetition. Both groups also benefitted from demonstration over spoken presentation, but only when the instructions were recalled verbally. These findings suggest that children with ADHD struggle to complete multi-step instructions, but that they benefit from action-based presentation and recall in the same way as typically developing children. These findings have important implications for educators, suggesting that motor-based methods of instruction-delivery might enhance classroom learning both for children with and without developmental disorders.

  11. Impaired Memory for Instructions in Children with Attention-Deficit Hyperactivity Disorder Is Improved by Action at Presentation and Recall

    Science.gov (United States)

    Yang, Tian-xiao; Allen, Richard J.; Holmes, Joni; Chan, Raymond C. K.

    2017-01-01

    Children with attention deficit hyperactivity disorder (ADHD) often fail to comply with teacher instructions in the classroom. Using action during presentation or recall can enhance typically developing children’s abilities to complete multi-step instruction sequences. In this study, we tested the ability to following instructions in children with ADHD under different conditions to explore whether they show the same beneficial effects of action. A total of 24 children with ADHD and 27 typically developing children either listened to or viewed demonstrations of instructions during encoding, and then either verbally repeated or physically performed the sequences during recall. This resulted in four conditions: spoken-verbal, spoken-enacted, demonstration-verbal, and demonstration-enacted. Children with ADHD were significantly impaired in all conditions of the following instructions task relative to the typically developing group. Both groups showed an enacted-recall advantage, with superior recall by physical performance than oral repetition. Both groups also benefitted from demonstration over spoken presentation, but only when the instructions were recalled verbally. These findings suggest that children with ADHD struggle to complete multi-step instructions, but that they benefit from action-based presentation and recall in the same way as typically developing children. These findings have important implications for educators, suggesting that motor-based methods of instruction-delivery might enhance classroom learning both for children with and without developmental disorders. PMID:28174550

  12. Comparing the Effectiveness of Paroxetine, Attention Modification Program and Combination of both on Improving Social Anxiety Symptoms

    Directory of Open Access Journals (Sweden)

    Aliasghar Asgharnejad Farid

    2012-09-01

    Full Text Available Introduction: Although the effectiveness of paroxetine and Attention Modification Program has been studied separately in treating social anxiety disorder, there has been no research comparing them according to the literature. The aim of this study was to compare the effectiveness of paroxetine, Attention Modification Program (AMP and combination of both on improving the Social Anxiety Symptoms.Methods:33 patients meeting DSM-IV-TR criteria for social anxiety disorder were randomly assigned in 3 groups: 11 in paroxetine group, 11 in AMP group and 11 in combined group. Treatment intervention was done during 8 weeks period. Social Phobia Inventory (SPIN, Beck Depression Inventory (BDI-II and Sheehan Disability Scale (SDS were administered before and after treatment intervention. One-way Analysis of Covariance (ANCOVA was used to determine the differences and efficacy of treatment interventions between groups. Data analysis was done by SPSS-16 software.Results:28 participants completed the treatment period. One-way ANCOVA results showed statistically significant differences in post-treatment scores of social phobia (p=0/007, depressive symptoms (p=0.007 and daily life functioning (p=0.011 between three groups. Bonferroni correction showed that combined treatment is significantly more effective than AMP in reducing social phobia symptoms (p=0.007, depressive symptoms (p=0.022 and enhancing daily life functioning (0.019. Yet, there were no significant differences between Paroxetine and combined treatment in all post-treatment scores (p=0.890, p=1.000, p=1.000 for social phobia, depressive symptoms and daily life functioning respectively. Paroxetine showed more significant improvement of depressive symptoms (p=0.016 and enhancing daily life functioning (p=0.045 than AMP. Also, there were no significant differences between paroxetine and AMP in reducing social anxiety symptoms.Discussion:It seems that paroxetine has wider effect in reducing social

  13. Improving Driver Performance. A Curriculum for Licensed Drivers.

    Science.gov (United States)

    Highway Users Federation for Safety and Mobility, Washington, DC.

    Curriculum material presented in this manual is for use in the development of an instructional program for drivers who either want or need to improve their driving performance. Three principal units are included: man and highway transportation, driver performance, and factors influencing driver behavior. Each unit is further divided into episodes…

  14. Improving TCP Performance over Mobile Satellite Channels: The ACKPrime Approach

    Science.gov (United States)

    Scott, Keith; Czetty, Stephen

    1998-01-01

    Various issues associated with "Improving TCP Performance over Mobile Satellite Channels: The ACKPrime Approach" are presented in viewgraph form. Specific topics include: 1) TCP over mobile satellite links; 2) ways of breaking the control loop at the groundstation; 3) ACK implementation; and 4) ACK performance.

  15. The design and performance of an improved target for MICE

    CERN Document Server

    Booth, C N; Langlands, J; Overton, E; Robinson, M; Smith, P J; Barber, G; Long, K R; Shepherd, B; Capocci, E; MacWaters, C; Tarrant, J

    2016-01-01

    The linear motor driving the target for the Muon Ionisation Cooling Experiment has been redesigned to improve its reliability and performance. A new coil-winding technique is described which produces better magnetic alignment and improves heat transport out of the windings. Improved field-mapping has allowed the more precise construction to be demonstrated, and an enhanced controller exploits the full features of the hardware, enabling increased acceleration and precision. The new user interface is described and analysis of performance data to monitor friction is shown to allow quality control of bearings and a measure of the ageing of targets during use.

  16. Improving Employee Satisfaction Priority through Performance Control Matrix

    Directory of Open Access Journals (Sweden)

    Shun-Hsing Chen

    2014-11-01

    Full Text Available The study addresses Performance Control Matrix (PCM to determine service quality items of priority for improvement. Most businesses focus on customer satisfaction when undertaking surveys of satisfaction and dissatisfaction, while generally neglecting employee satisfaction. Therefore, this study develops an integrated model to improve service quality in Taiwanese finance industry employees. A questionnaire is designed to determine the priority of improvement objectives derived from certain questionnaire items that fall into the improvement zone of the PCM. Ten items are found to fall into the improvement zone of the PCM. The present results show that the finance industry employees surveyed in Taiwan were dissatisfied with their job security, salaries, annual bonus, and fair distribution of operational profits. The ten improvement items mostly belong to two dimensions - ‘Pay and Benefits’ and ‘Motivation’. The managers of the financial institutions should seek to improve these quality attributes by devoting more resources to these items, thus promoting employee satisfaction.

  17. Improving Reactive Ad Hoc Routing Performance by Geographic Route Length

    Institute of Scientific and Technical Information of China (English)

    CAO Yuan-da; YU Yan-bing; LU Di

    2005-01-01

    In order to help reactive ad hoc routing protocols select better-performance routes, a novel metric named geographic route length (GRL) is proposed. The relationship between GRL metric and routing performance is analyzed in detail. Combined with hop metric, GRL is applied into the original ad hoc on-demand distance vector (AODV) to demonstrate its effectiveness. Simulation experiments have shown that GRL can effectively reduce packet delay and route discovery frequency, thus can improve reactive ad hoc routing performance.

  18. Implementing a Nurse Manager Profile to Improve Unit Performance.

    Science.gov (United States)

    Krugman, Mary E; Sanders, Carolyn L

    2016-06-01

    Nurse managers face significant pressures in the rapidly changing healthcare environment. Staying current with multiple sources of data, including reports that detail institutional and unit performance outcomes, is particularly challenging. A Nurse Manager Customized Profile was developed at a western academic hospital to provide a 1-page visual of pertinent data to help managers and director supervisors focus coaching to improve unit performance. Use of the Decisional Involvement Scale provided new insights into measuring manager performance.

  19. Attentional bias to pain and social threat in pediatric patients with functional abdominal pain and pain-free youth before and after performance evaluation.

    Science.gov (United States)

    Beck, Joy E; Lipani, Tricia A; Baber, Kari F; Dufton, Lynette; Garber, Judy; Smith, Craig A; Walker, Lynn S

    2011-05-01

    This study investigated attentional biases for pain and social threat versus neutral stimuli in 54 youth with functional abdominal pain (FAP) and 53 healthy control subjects (ages 10 to 16 years). We assessed attentional bias using a visual probe detection task (PDT) that presented pain and social threat words in comparison to neutral words at conscious (1250 ms) and preconscious (20 ms) presentation rates. We administered the PDT before and after random assignment of participants to a laboratory stressor--failure versus success feedback regarding their performance on a challenging computer game. All analyses controlled for trait anxiety. At the conscious rate of stimulus presentation, FAP patients exhibited preferential attention toward pain compared with neutral stimuli and compared with the control group. FAP patients maintained preferential attention toward conscious pain stimuli after performance feedback in both failure and success conditions. At the preconscious rate of stimulus presentation, FAP patients' attention was neutral at baseline but increased significantly toward pain stimuli after performance feedback in both failure and success conditions. FAP patients' somatic symptoms increased in both failure and success conditions; control youth's somatic symptoms only increased after failure. Regarding social threat, neither FAP nor control youth exhibited attentional bias toward social threat compared with neutral stimuli at baseline, but both FAP and control youth in the failure condition significantly increased attention away from social threat after failure feedback. Results suggest that FAP patients preferentially attend to pain stimuli in conscious awareness. Moreover, performance evaluation may activate their preconscious attention to pain stimuli.

  20. The control algorithm improving performance of electric load simulator

    Science.gov (United States)

    Guo, Chenxia; Yang, Ruifeng; Zhang, Peng; Fu, Mengyao

    2017-01-01

    In order to improve dynamic performance and signal tracking accuracy of electric load simulator, the influence of the moment of inertia, stiffness, friction, gaps and other factors on the system performance were analyzed on the basis of researching the working principle of load simulator in this paper. The PID controller based on Wavelet Neural Network was used to achieve the friction nonlinear compensation, while the gap inverse model was used to compensate the gap nonlinear. The compensation results were simulated by MATLAB software. It was shown that the follow-up performance of sine response curve of the system became better after compensating, the track error was significantly reduced, the accuracy was improved greatly and the system dynamic performance was improved.

  1. Beyond symptom control for attention-deficit hyperactivity disorder (ADHD): what can parents do to improve outcomes?

    Science.gov (United States)

    Tarver, J; Daley, D; Sayal, K

    2015-01-01

    Attention-deficit hyperactivity disorder (ADHD) and its associated behavioural manifestations develop and progress as the result of complex gene-environment interactions. Parents exert a substantial influence and play a major role in their child's social environment. Despite this, recent evidence has suggested that adapting the child's environment via parenting interventions has minimal effects on child ADHD symptoms when analysing data from informants who are probably blind to treatment allocation. However, adverse parenting and family environments may act as a source of environmental risk for a number of child outcomes beyond ADHD symptoms. This is a narrative review that critically discusses whether parenting interventions are beneficial for alternative functioning outcomes in ADHD including neuropsychological, academic and social functioning and disruptive behaviour and how parenting and familial environments may be associated with these outcomes. In addition, the review explores how parental depression and parenting efficacy impact on capacity for optimal parenting and whether parenting interventions benefit parents too. A review of the evidence suggests that with modification, parenting interventions are beneficial for a number of outcomes other than ADHD symptom reduction. Improving the parent-child relationship may have indirect benefits for disruptive behaviour. Furthermore, parenting behaviours may directly benefit child neuropsychological, academic and social functioning. Parenting interventions can have therapeutic benefits for parents as well as children, which is important as parent and child well-being is likely to have a transactional relationship. Evaluation of the clinical success of parenting interventions should focus on a wider range of outcomes in order to aid understanding of the multifaceted benefits that they may be able to offer. Parenting interventions should not be seen as a redundant adjunct to medication in multi-modal treatment

  2. Connectivity supporting attention in children with attention deficit hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Anita D. Barber

    2015-01-01

    While CON–DMN anti-correlation is associated with improved attention in ADHD, other circuitry supports improved attention in TD children. Greater CON–DMN anti-correlation supported better attentional control in children with ADHD, but worse attentional control in TD children. On the other hand, greater DMN–occipital anti-correlation supported better attentional control in TD children.

  3. Assessing the Effectiveness of a Learning Community Course Design to Improve the Math Performance of First-Year Students

    Science.gov (United States)

    Hansen, Michele J.; Meshulam, Susan; Parker, Brooke

    2013-01-01

    National attention is focused on the persistent high failure rates for students enrolled in math courses, and the search for strategies to change these outcomes is on. This study used a mixed-method research design to assess the effectiveness of a learning community course designed to improve the math performance levels of firstyear students.…

  4. Improving the efficacy of ERP-based BCIs using different modalities of covert visuospatial attention and a genetic algorithm-based classifier.

    Directory of Open Access Journals (Sweden)

    Mauro Marchetti

    Full Text Available We investigated whether the covert orienting of visuospatial attention can be effectively used in a brain-computer interface guided by event-related potentials. Three visual interfaces were tested: one interface that activated voluntary orienting of visuospatial attention and two interfaces that elicited automatic orienting of visuospatial attention. We used two epoch classification procedures. The online epoch classification was performed via Independent Component Analysis, and then it was followed by fixed features extraction and support vector machines classification. The offline epoch classification was performed by means of a genetic algorithm that permitted us to retrieve the relevant features of the signal, and then to categorise the features with a logistic classifier. The offline classification, but not the online one, allowed us to differentiate between the performances of the interface that required voluntary orienting of visuospatial attention and those that required automatic orienting of visuospatial attention. The offline classification revealed an advantage of the participants in using the "voluntary" interface. This advantage was further supported, for the first time, by neurophysiological data. Moreover, epoch analysis was performed better with the "genetic algorithm classifier" than with the "independent component analysis classifier". We suggest that the combined use of voluntary orienting of visuospatial attention and of a classifier that permits feature extraction ad personam (i.e., genetic algorithm classifier can lead to a more efficient control of visual BCIs.

  5. Improving the Efficacy of ERP-Based BCIs Using Different Modalities of Covert Visuospatial Attention and a Genetic Algorithm-Based Classifier

    Science.gov (United States)

    Marchetti, Mauro; Onorati, Francesco; Matteucci, Matteo; Mainardi, Luca; Piccione, Francesco; Silvoni, Stefano; Priftis, Konstantinos

    2013-01-01

    We investigated whether the covert orienting of visuospatial attention can be effectively used in a brain-computer interface guided by event-related potentials. Three visual interfaces were tested: one interface that activated voluntary orienting of visuospatial attention and two interfaces that elicited automatic orienting of visuospatial attention. We used two epoch classification procedures. The online epoch classification was performed via Independent Component Analysis, and then it was followed by fixed features extraction and support vector machines classification. The offline epoch classification was performed by means of a genetic algorithm that permitted us to retrieve the relevant features of the signal, and then to categorise the features with a logistic classifier. The offline classification, but not the online one, allowed us to differentiate between the performances of the interface that required voluntary orienting of visuospatial attention and those that required automatic orienting of visuospatial attention. The offline classification revealed an advantage of the participants in using the “voluntary” interface. This advantage was further supported, for the first time, by neurophysiological data. Moreover, epoch analysis was performed better with the “genetic algorithm classifier” than with the “independent component analysis classifier”. We suggest that the combined use of voluntary orienting of visuospatial attention and of a classifier that permits feature extraction ad personam (i.e., genetic algorithm classifier) can lead to a more efficient control of visual BCIs. PMID:23342043

  6. Improving the efficacy of ERP-based BCIs using different modalities of covert visuospatial attention and a genetic algorithm-based classifier.

    Science.gov (United States)

    Marchetti, Mauro; Onorati, Francesco; Matteucci, Matteo; Mainardi, Luca; Piccione, Francesco; Silvoni, Stefano; Priftis, Konstantinos

    2013-01-01

    We investigated whether the covert orienting of visuospatial attention can be effectively used in a brain-computer interface guided by event-related potentials. Three visual interfaces were tested: one interface that activated voluntary orienting of visuospatial attention and two interfaces that elicited automatic orienting of visuospatial attention. We used two epoch classification procedures. The online epoch classification was performed via Independent Component Analysis, and then it was followed by fixed features extraction and support vector machines classification. The offline epoch classification was performed by means of a genetic algorithm that permitted us to retrieve the relevant features of the signal, and then to categorise the features with a logistic classifier. The offline classification, but not the online one, allowed us to differentiate between the performances of the interface that required voluntary orienting of visuospatial attention and those that required automatic orienting of visuospatial attention. The offline classification revealed an advantage of the participants in using the "voluntary" interface. This advantage was further supported, for the first time, by neurophysiological data. Moreover, epoch analysis was performed better with the "genetic algorithm classifier" than with the "independent component analysis classifier". We suggest that the combined use of voluntary orienting of visuospatial attention and of a classifier that permits feature extraction ad personam (i.e., genetic algorithm classifier) can lead to a more efficient control of visual BCIs.

  7. Frontal midline theta rhythm is correlated with cardiac autonomic activities during the performance of an attention demanding meditation procedure.

    Science.gov (United States)

    Kubota, Y; Sato, W; Toichi, M; Murai, T; Okada, T; Hayashi, A; Sengoku, A

    2001-04-01

    Frontal midline theta rhythm (Fm theta), recognized as distinct theta activity on EEG in the frontal midline area, reflects mental concentration as well as meditative state or relief from anxiety. Attentional network in anterior frontal lobes including anterior cingulate cortex is suspected to be the generator of this activity, and the regulative function of the frontal neural network over autonomic nervous system (ANS) during cognitive process is suggested. However no studies have examined peripheral autonomic activities during Fm theta induction, and interaction of central and peripheral mechanism associated with Fm theta remains unclear. In the present study, a standard procedure of Zen meditation requiring sustained attention and breath control was employed as the task to provoke Fm theta, and simultaneous EEG and ECG recordings were performed. For the subjects in which Fm theta activities were provoked (six men, six women, 48% of the total subjects), peripheral autonomic activities were evaluated during the appearance of Fm theta as well as during control periods. Successive inter-beat intervals were measured from the ECG, and a recently developed method of analysis by Toichi et al. (J. Auton. Nerv. Syst. 62 (1997) 79-84) based on heart rate variability was used to assess cardiac sympathetic and parasympathetic functions separately. Both sympathetic and parasympathetic indices were increased during the appearance of Fm theta compared with control periods. Theta band activities in the frontal area were correlated negatively with sympathetic activation. The results suggest a close relationship between cardiac autonomic function and activity of medial frontal neural circuitry.

  8. Performance Report and Improvements in CV Machine Areas

    CERN Document Server

    Monsted, A

    2000-01-01

    The performance of cooling and ventilation (CV) equipment is defined as its availability to the PS, SPS and LEP accelerators. Three teams for the accelerators plus a Utilities team, which receives performance information from the physics and technical control room, carry out the operation of this equipment. Collected performance statistics as well as data from the Computer Aided Maintenance Management system (CAMM) and supervision system provide information on the exact state of the CV equipment. This is used to more effectively schedule preventive maintenance which, by reducing system failures, results in improved equipment performance. This paper will present performance data and discuss the prospects for improving it through the use of an updated version of CAMM and a new supervision system.

  9. Performance Improvement of a Centrifugal Compressor by Passive Means

    Directory of Open Access Journals (Sweden)

    N. Sitaram

    2012-01-01

    Full Text Available The present experimental investigation deals with performance improvement of a low-speed centrifugal compressor by inexpensive passive means such as turbulence generator placed at different positions and partial shroud near the rotor blade tip. The experiments are carried out at three values of tip clearance, namely 2.2%, 5.1%, and 7.9% of rotor blade height at the exit. Performance tests are carried out for a total of 13 configurations. From these measurements, partial shroud is found to give the best performance. The improvement in the compressor performance may be due to the reduction of tip leakage flows by the small extension of partial shroud (2 mm on the pressure surface side. Although there is nominal change in performance due to turbulence generator (TG, TG has beneficial effect of increased operating range.

  10. Improvability of assembly systems I: Problem formulation and performance evaluation

    Directory of Open Access Journals (Sweden)

    Chiang S.-Y.

    2000-01-01

    Full Text Available This work develops improvability theory for assembly systems. It consists of two parts.Part I includes the problem formulation and the analysis technique. Part II presents the so-called improvability indicators and a case study. Improvability theory addresses the questions of improving performance in production systems with unreliable machines. We consider both constrained and unconstrained improvability. In the constrained case, the problem consists of determining if there exists a re-distribution of resources (inventory and workforce, which leads to an increase in the system's production rate. In the unconstrained case, the problem consists of identifying a machine and a buffer, which impede the system performance in the strongest manner. The investigation of the improvability properties requires an expression for the system performance measures as functions of the machine and buffer parameters. This paper presents a method for evaluating these functions and illustrates their practical utility using a case study at an automotive components plant. Part II uses the method developed here to establish conditions of improvability and to describe additional results of the case study.

  11. Neurofeedback as an Intervention to Improve Reading Achievement in Students with Attention Deficit Hyperactivity Disorder, Inattentive Subtype

    Science.gov (United States)

    La Marca, Jeffry Peter

    2014-01-01

    Attention deficit disorders are among the most prevalent and widely studied of all psychiatric disorders. The National Center for Health Statistics reports that 9.0% of children (12.3% of boys and 5.5% of girls) between ages 5 to 17 have been diagnosed with ADHD. Research consistently demonstrates that attention deficits have a deleterious effect…

  12. Framework for continuous performance improvement in small drinking water systems.

    Science.gov (United States)

    Bereskie, Ty; Haider, Husnain; Rodriguez, Manuel J; Sadiq, Rehan

    2017-01-01

    Continuous performance improvement (CPI) can be a useful approach to overcome water quality problems impacting small communities. Small drinking water systems (SDWSs) struggle to meet regulatory requirements and often lack the economic and human resource flexibility for immediate improvement. A CPI framework is developed to provide SDWS managers and operators an approach to gauge their current performance against similar systems and to track performance improvement from the implementation of the new technologies or innovations into the future. The proposed CPI framework incorporates the use of a water quality index (WQI) and functional performance benchmarking to evaluate and compare drinking water quality performance of an individual water utility against that of a representative benchmark. The results are then used to identify and prioritize the most vulnerable water quality indicators and subsequently identify and prioritize performance improvement strategies. The proposed CPI framework has been demonstrated using data collected from SDWSs in the province of Newfoundland and Labrador (NL), Canada and using the Canadian Council of Ministers of the Environment (CCME) WQI.

  13. Mindfulness training affects attention--or is it attentional effort?

    Science.gov (United States)

    Jensen, Christian Gaden; Vangkilde, Signe; Frokjaer, Vibe; Hasselbalch, Steen G

    2012-02-01

    Improvements in attentional performance are at the core of proposed mechanisms for stress reduction in mindfulness meditation practices. However, this claim can be questioned because no previous studies have actively manipulated test effort in control groups and controlled for effects of stress reduction per se. In a blinded design, 48 young, healthy meditation novices were randomly assigned to a mindfulness-based stress reduction (MBSR), nonmindfulness stress reduction (NMSR), or inactive control group. At posttest, inactive controls were randomly split into nonincentive and incentive controls, the latter receiving a financial reward to improve attentional performance. Pre- and postintervention, 5 validated attention paradigms were employed along with self-report scales on mindfulness and perceived stress and saliva cortisol samples to measure physiological stress. Attentional effects of MBSR, NMSR, and the financial incentive were comparable or significantly larger in the incentive group on all reaction-time-based measures. However, selective attention in the MBSR group improved significantly more than in any other group. Similarly, only the MBSR intervention improved the threshold for conscious perception and visual working memory capacity. Furthermore, stress-reducing effects of MBSR were supported because those in the MBSR group showed significantly less perceived and physiological stress while increasing their mindfulness levels significantly. We argue that MBSR may contribute uniquely to attentional improvements but that further research focusing on non-reaction-time-based measures and outcomes less confounded by test effort is needed. Critically, our data demonstrate that previously observed improvements of attention after MBSR may be seriously confounded by test effort and nonmindfulness stress reduction.

  14. Visuospatial selective attention in chickens.

    Science.gov (United States)

    Sridharan, Devarajan; Ramamurthy, Deepa L; Schwarz, Jason S; Knudsen, Eric I

    2014-05-13

    Voluntary control of attention promotes intelligent, adaptive behaviors by enabling the selective processing of information that is most relevant for making decisions. Despite extensive research on attention in primates, the capacity for selective attention in nonprimate species has never been quantified. Here we demonstrate selective attention in chickens by applying protocols that have been used to characterize visual spatial attention in primates. Chickens were trained to localize and report the vertical position of a target in the presence of task-relevant distracters. A spatial cue, the location of which varied across individual trials, indicated the horizontal, but not vertical, position of the upcoming target. Spatial cueing improved localization performance: accuracy (d') increased and reaction times decreased in a space-specific manner. Distracters severely impaired perceptual performance, and this impairment was greatly reduced by spatial cueing. Signal detection analysis with an "indecision" model demonstrated that spatial cueing significantly increased choice certainty in localizing targets. By contrast, error-aversion certainty (certainty of not making an error) remained essentially constant across cueing protocols, target contrasts, and individuals. The results show that chickens shift spatial attention rapidly and dynamically, following principles of stimulus selection that closely parallel those documented in primates. The findings suggest that the mechanisms that control attention have been conserved through evolution, and establish chickens--a highly visual species that is easily trained and amenable to cutting-edge experimental technologies--as an attractive model for linking behavior to neural mechanisms of selective attention.

  15. Carbohydrate mouth rinse: does it improve endurance exercise performance?

    Directory of Open Access Journals (Sweden)

    Painelli Vitor

    2010-08-01

    Full Text Available Abstract It is well known that carbohydrate (CHO supplementation can improve performance in endurance exercises through several mechanisms such as maintenance of glycemia and sparing endogenous glycogen as well as the possibility of a central nervous-system action. Some studies have emerged in recent years in order to test the hypothesis of ergogenic action via central nervous system. Recent studies have demonstrated that CHO mouth rinse can lead to improved performance of cyclists, and this may be associated with the activation of brain areas linked to motivation and reward. These findings have already been replicated in other endurance modalities, such as running. This alternative seems to be an attractive nutritional tool to improve endurance exercise performance.

  16. Improving the Student’s Performance Using Educational Data Mining

    Directory of Open Access Journals (Sweden)

    K.Shanmuga Priya

    2013-01-01

    Full Text Available The main goal of educational data mining is to improve the student performance. The usage of data mining techniques which achieves the goal in an efficient manner. The discovery of knowledge that extract from the end semester [1] is one of the method for improving the quality of higher education. In the higher education, the analysis on enrolment of student’s performance in a particular course, the student talent, confidence, studies and ethic helps to get more knowledge. In this research, the data classification and decision tree [1] which helps to improve the student’s performance in a better way. But with the inclusion of extracurricular activities with the above data mining techniques makes quality of education in an easiest way. This type of approach gives high confidence to students in their studies. This method helps to identify the students who need special advising or counseling by the teacher which gives high quality of education.

  17. Teacher’s comprehensive training strategy for improving didactics performance

    OpenAIRE

    Pozas, W. J; Marrero, O. S.

    2014-01-01

    The paper describes a Teacher’s comprehensive training strategy for improving didactics performance, together with its theoretical foundations. The strategy is structured into several dimensions related to teachers’ development (lesson planning, continuing education and research). It is organized into two phases and seven stages intended to improve leadership in the teaching-learning process. The finding are the expression of a comprehensive approach to school organization at Services Polytec...

  18. Improving Building Performance through Integrating Constructability in the Design Process

    OpenAIRE

    Ezzat Othman, Ayman Ahmed

    2011-01-01

    The traditional procurment approaches commonly adopted in construction projects and the involvement of multitude of various project participants with diverse objectives, skills and interests tended to separate design from construction.This separation obstructs contractors from providing designers with construction feedback and suggestions for design improvement, which ultimately hampers the improvement of building performance. Because of the importance of the design phase and the vit...

  19. Mechanisms of attention: Psychophysics, cognitive psychology, and cognitive neuroscience.

    Science.gov (United States)

    Lu, Zhong-Lin

    2008-01-01

    Sensory physiologists and psychologists have recognized the importance of attention on human performance for more than 100 years. Since the 1970s, controlled and extensive experiments have examined effects of selective attention to a location in space or to an object. In addition to behavioral studies, cognitive neuroscientists have investigated the neural bases of attention. In this paper, I briefly review some classical attention paradigms, recent advances on the theory of attention, and some new insights from psychophysics and cognitive neuroscience. The focus is on the mechanisms of attention, that is, how attention improves human performance. Situations in which the perception of objects is unchanged, but performance may differ due to different decision structures, are distinguished from those in which attention changes the perceptual processes. The perceptual template model is introduced as a theoretical framework for analyzing mechanisms of attention. I also present empirical evidence for two attention mechanisms, stimulus enhancement and external noise exclusion, from psychophysics, neurophysiology and brain imaging.

  20. Improvement on Frequency Performance of SOI SiGe HBT

    Institute of Scientific and Technical Information of China (English)

    DAI Guang-hao; WANG Sheng-rong; LI Wen-jie

    2006-01-01

    Based on the advantages of SOI technology,the frequency performance of SiGe HBT with SOI structure has been simulated. Compared with bulk SiGe HBT,the results show that the buried oxide layer(BOX) can reduce collector-base capacitance CCB with the maximum value 89.3%,substrate-base capacitance CSB with 94.6%,and the maximum oscillation frequency is improved by 2.7. The SOI structure improves the frequency performance of SiGe HBT,which is adaptable to high-speed and high power applications.

  1. Lightning Performance on Overhead Distribution Lines : After Improvement Field Observation

    Directory of Open Access Journals (Sweden)

    Reynaldo Zoro

    2009-11-01

    Full Text Available Two feeders of 20 kV overhead distribution lines which are located in a high lightning density area are chosen to be observed as a field study due to their good lightning performance after improvement of lightning protection system. These two feeders used the new overhead ground wire and new line arrester equipped with lightning counter on the main lines. The significant reduced of lines outages are reported. Study was carried out to observe these improvements by comparing to the other two feeders line which are not improved and not equipped yet with the ground wire and line arrester. These two feeders located in the nearby area. Two cameras were installed to record the trajectory of the lightning strikes on the improved lines. Lightning peak currents are measured using magnetic tape measurement system installed on the grounding lead of lightning arrester. Lightning overvoltage calculations are carried out by using several scenarios based on observation results and historical lightning data derived from lightning detection network. Lightning overvoltages caused by indirect or direct strikes are analyzed to get the lightning performance of the lines. The best scenario was chosen and performance of the lines were improved significantly by installing overhead ground wire and improvement of lightning arrester installation.

  2. Slow oscillating transcranial direct current stimulation during non-rapid eye movement sleep improves behavioral inhibition in attention-deficit/ hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Manuel Tobias Munz

    2015-08-01

    Full Text Available Background: Behavioral inhibition, which is a later-developing executive function (EF and anatomically located in prefrontal areas, is impaired in attention-deficit and hyperactivity disorder (ADHD. While optimal EFs have been shown to depend on efficient sleep in healthy subjects, the impact of sleep problems, frequently reported in ADHD, remains elusive. Findings of macroscopic sleep changes in ADHD are inconsistent, but there is emerging evidence for distinct microscopic changes with a focus on prefrontal cortical regions and non-rapid eye movement (non-REM slow-wave sleep. Recently, slow oscillations (SO during non-REM sleep were found to be less functional and, as such, may be involved in sleep-dependent memory impairments in ADHD. Objective: By augmenting slow-wave power through bilateral, slow oscillating transcranial direct current stimulation (so-tDCS, frequency = 0.75 Hz during non-REM sleep, we aimed to improve daytime behavioral inhibition in children with ADHD. Methods: 14 boys (10-14 yrs diagnosed with ADHD were included. In a randomized, double-blind, cross-over design, patients received so-tDCS either in the first or in the second experimental sleep night. Inhibition control was assessed with a visuomotor go/no-go task. Intrinsic alertness was assessed with a simple stimulus response task. To control for visuomotor performance, motor memory was assessed with a finger sequence tapping task. Results: SO-power was enhanced during early non-REM sleep, accompanied by slowed reaction times and decreased standard deviations of reaction times, in the go/no-go task after so-tDCS. In contrast, intrinsic alertness and motor memory performance were not improved by so-tDCS. Conclusion: Since behavioral inhibition but not intrinsic alertness or motor memory was improved by so-tDCS, our results suggest that lateral prefrontal slow oscillations during sleep might play a specific role for executive functioning in ADHD.

  3. The Improvement of Emotion and Attention Regulation after a 6-Week Training of Focused Meditation: A Randomized Controlled Trial

    Science.gov (United States)

    Menezes, Carolina Baptista; Buratto, Luciano G.; Erthal, Fátima; Pereira, Mirtes G.; Bizarro, Lisiane

    2013-01-01

    Self-regulatory trainings can be an effective complementary treatment for mental health disorders. We investigated the effects of a six-week-focused meditation training on emotion and attention regulation in undergraduates randomly allocated to a meditation, a relaxation, or a wait-list control group. Assessment comprised a discrimination task that investigates the relationship between attentional load and emotional processing and self-report measures. For emotion regulation, results showed greater reduction in emotional interference in the low attentional load condition in meditators, particularly compared to relaxation. Only meditators presented a significant association between amount of weekly practice and the reduction in emotion interference in the task and significantly reduced image ratings of negative valence and arousal, perceived anxiety and difficulty during the task, and state and trait-anxiety. For attention regulation, response bias during the task was analyzed through signal detection theory. After training, meditation and relaxation significantly reduced bias in the high attentional load condition. Importantly, there was a dose-response effect on general bias: the lowest in meditation, increasing linearly across relaxation and wait-list. Only meditators reduced omissions in a concentrated attention test. Focused meditation seems to be an effective training for emotion and attention regulation and an alternative for treatments in the mental health context. PMID:23935694

  4. The Improvement of Emotion and Attention Regulation after a 6-Week Training of Focused Meditation: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Carolina Baptista Menezes

    2013-01-01

    Full Text Available Self-regulatory trainings can be an effective complementary treatment for mental health disorders. We investigated the effects of a six-week-focused meditation training on emotion and attention regulation in undergraduates randomly allocated to a meditation, a relaxation, or a wait-list control group. Assessment comprised a discrimination task that investigates the relationship between attentional load and emotional processing and self-report measures. For emotion regulation, results showed greater reduction in emotional interference in the low attentional load condition in meditators, particularly compared to relaxation. Only meditators presented a significant association between amount of weekly practice and the reduction in emotion interference in the task and significantly reduced image ratings of negative valence and arousal, perceived anxiety and difficulty during the task, and state and trait-anxiety. For attention regulation, response bias during the task was analyzed through signal detection theory. After training, meditation and relaxation significantly reduced bias in the high attentional load condition. Importantly, there was a dose-response effect on general bias: the lowest in meditation, increasing linearly across relaxation and wait-list. Only meditators reduced omissions in a concentrated attention test. Focused meditation seems to be an effective training for emotion and attention regulation and an alternative for treatments in the mental health context.

  5. Teacher’s comprehensive training strategy for improving didactics performance

    Directory of Open Access Journals (Sweden)

    Pozas, W. J

    2014-07-01

    Full Text Available The paper describes a Teacher’s comprehensive training strategy for improving didactics performance, together with its theoretical foundations. The strategy is structured into several dimensions related to teachers’ development (lesson planning, continuing education and research. It is organized into two phases and seven stages intended to improve leadership in the teaching-learning process. The finding are the expression of a comprehensive approach to school organization at Services Polytechnic School “Horacio Cobiellas Domínguez” resulting in teachers’ academic and scientific development and a significant growth of the staff scientific potentials manifested in scientific forum enrolment. The resulting impact should lead to a general use of the proposed strategy in the Polytechnic school web. Key words: professional performance, pedagogic professional performance, didactic professional performance, teachers’ developmental strategy

  6. Performance of Gannan Yak and Approaches for Improvement

    Institute of Scientific and Technical Information of China (English)

    王槐田

    2005-01-01

    At present, the yak population reached to 1.1 million in Gannan prefecture. Yak is dominant livestock in Gannan,and is the main source of herdsman income. In recent years, the population of Gannan yak continuously increased, but the performances such as body weight, dressing percentage and reproductivity are dropping.In order to improve quality, performance and economic benefits of yak production,it is very urgent to strengthen yak selective breeding.

  7. Performance improvement for optical packet switch with shared buffers

    Institute of Scientific and Technical Information of China (English)

    Junjie Yang; Qingji Zeng; Jie Li; Tong Ye; Guolong Zhu

    2005-01-01

    @@ In this paper, an inner wavelength method is proposed to enlarge buffering capacity of shared fiber delay line buffers. In addition, an optical packet switch called extended shared buffer type optical packet switch(extended SB-OPS) is proposed to realize the inner wavelength method. In order to further improve performance of extended SB-OPS, a greedy algorithm based on inner wavelength method is introduced.The performance of extended SB-OPS is evaluated by simulation experiments.

  8. Relationship between blood manganese levels and children's attention, cognition, behavior, and academic performance--a nationwide cross-sectional study.

    Science.gov (United States)

    Bhang, Soo-Young; Cho, Soo-Churl; Kim, Jae-Won; Hong, Yun-Chul; Shin, Min-Sup; Yoo, Hee Jeong; Cho, In Hee; Kim, Yeni; Kim, Bung-Nyun

    2013-10-01

    Manganese (Mn) is neurotoxic at high concentrations. However, Mn is an essential element that can protect against oxidative damage; thus, extremely low levels of Mn might be harmful. Our aim was to examine whether either high or low environmental Mn exposure is related to academic and attention function development among school-aged children. This cross-sectional study included 1089 children 8-11 years of age living in five representative areas in South Korea. Blood Mn, blood lead, and urine cotinine were measured. We assessed IQ with the Wechsler Abbreviated Scale of Intelligence; attention with a computerized continuous performance test called the Attention-deficit/hyperactivity disorder (ADHD) Diagnostic System (ADS), the Korean version of the Stroop Color-Word Test, the Children's Color Trails Test (CCTT), and the ADHD Rating Scale; academic functions with the Learning Disability Evaluation Scale (LDES); and emotional and behavioral problems with the Korean version of the Child Behavior Checklist (CBCL). We further assessed the presence of ADHD using a highly structured diagnostic interview, the Diagnostic Interview Schedule for Children Version IV (DISC-IV). The median blood concentration of Mn was 14.14 µg/L. We observed a nonlinear association between the CCTT2 completion time and the CPT commission error (F=3.14, p=0.03 and F=4.05, p=0.01, respectively). We divided the data into three groups: lower (21.453 µg/L) and middle 90th percentile to determine whether a lack or overload of Mn could cause adverse effects. After adjusting for urine cotinine, blood lead, children's IQ, and other potential confounders, the high Mn group showed lower scores in thinking (B=-0.83, p=0.006), reading (B=-0.93, p=0.004), calculations (B=-0.72, p=0.005), and LQ (B=-4.06, p=0.006) in the LDES and a higher commission error in the CPT (B=8.02, p=0.048). The low Mn group showed lower color scores in the Stroop test (B=-3.24, p=0.040). We found that excess Mn in children is

  9. The influence of mastery-avoidance goals on performance improvement

    NARCIS (Netherlands)

    Van Yperen, Nico W.; Elliot, Andrew J.; Anseel, Frederik

    2009-01-01

    Two experiments focused on examining the influence of mastery-avoidance goals on performance improvement, and more specifically, on mastery-avoidance goals grounded in an intrapersonal standard. That is, herein, mastery-avoidance goals entail striving to avoid doing worse than one has done before. B

  10. Driving Performance Improvements by Integrating Competencies with Human Resource Practices

    Science.gov (United States)

    Lee, Jin Gu; Park, Yongho; Yang, Gi Hun

    2010-01-01

    This study explores the issues in the development and application of a competency model and provides implications for more precise integration of competencies into human resource (HR) functions driving performance improvement. This research is based on a case study from a Korean consumer corporation. This study employed document reviews,…

  11. Performance in physiology evaluation: possible improvement by active learning strategies.

    Science.gov (United States)

    Montrezor, Luís H

    2016-12-01

    The evaluation process is complex and extremely important in the teaching/learning process. Evaluations are constantly employed in the classroom to assist students in the learning process and to help teachers improve the teaching process. The use of active methodologies encourages students to participate in the learning process, encourages interaction with their peers, and stimulates thinking about physiological mechanisms. This study examined the performance of medical students on physiology over four semesters with and without active engagement methodologies. Four activities were used: a puzzle, a board game, a debate, and a video. The results show that engaging in activities with active methodologies before a physiology cognitive monitoring test significantly improved student performance compared with not performing the activities. We integrate the use of these methodologies with classic lectures, and this integration appears to improve the teaching/learning process in the discipline of physiology and improves the integration of physiology with cardiology and neurology. In addition, students enjoy the activities and perform better on their evaluations when they use them.

  12. Warning Signals for Poor Performance Improve Human-Robot Interaction

    NARCIS (Netherlands)

    van den Brule, Rik; Bijlstra, Gijsbert; Dotsch, Ron; Haselager, Pim; Wigboldus, Daniel HJ

    2016-01-01

    The present research was aimed at investigating whether human-robot interaction (HRI) can be improved by a robot’s nonverbal warning signals. Ideally, when a robot signals that it cannot guarantee good performance, people could take preventive actions to ensure the successful completion of the robot

  13. Improving Performance through Knowledge Translation in the Veterans Health Administration

    Science.gov (United States)

    Francis, Joseph; Perlin, Jonathan B.

    2006-01-01

    The Veterans Health Administration (VA) provides a case study for linking performance measurement, information technology, and aligned research efforts to facilitate quality improvement in a large, complex health system. Dialogue between clinical researchers and VA leaders occurs through structured activities (e.g., the Quality Enhancement…

  14. A case study of improved performance in archery using hypnosis.

    Science.gov (United States)

    Robazza, C; Bortoli, L

    1995-12-01

    Active-alert hypnosis and traditional hypnosis procedures can be combined and applied in sport following the lines of an isomorphic model. A case study of improved shooting performance in an adult expert archer after 20 weeks of mental training is reported.

  15. Warning signals for poor performance improve human-robot interaction

    NARCIS (Netherlands)

    Brule, R. van den; Bijlstra, G.; Dotsch, R.; Haselager, W.F.G.; Wigboldus, D.H.J.

    2016-01-01

    The present research was aimed at investigating whether human-robot interaction (HRI) can be improved by a robot's nonverbal warning signals. Ideally, when a robot signals that it cannot guarantee good performance, people could take preventive actions to ensure the successful completion of the robot

  16. Recent improvements in the performance of the SPS

    CERN Document Server

    Faugier, A; Hatton, V; Hilaire, A; Lauckner, R; Miles, J; Péraire, S; Thomas, D; Warman, A

    1980-01-01

    Describes the most relevant factors that have contributed to the steady improvement in performance of the SPS are a supplier of protons for the high energy physics programme of CERN. The maximum intensity is now 2.7*10/sup 13/ protons per pulse, the slow spills are better and for 90% of the scheduled time the beam is on the targets. (0 refs) .

  17. Network Performance Improvement under Epidemic Failures in Optical Transport Networks

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Ruepp, Sarah Renée

    2013-01-01

    In this paper we investigate epidemic failure spreading in large- scale GMPLS-controlled transport networks. By evaluating the effect of the epidemic failure spreading on the network, we design several strategies for cost-effective network performance improvement via differentiated repair times...

  18. CREDIBILITY AND TRANSPARENCY - SOURCES FOR THE IMPROVEMENT OF MACROECONOMIC PERFORMANCES

    Directory of Open Access Journals (Sweden)

    Vorzsak Magdalena

    2009-05-01

    Full Text Available The purpose of this paper is to show that the monetary policy credibility and transparency represent two powerful sources for the improvement of macroeconomic performances. In order to achieve this goal, the authors adapted the methodology developed by Kr

  19. The CF6 jet engine performance improvement: New front mount

    Science.gov (United States)

    Fasching, W. A.

    1979-01-01

    The New Front Mount was evaluated in component tests including stress, deflection/distortion and fatigue tests. The test results demonstrated a performance improvement of 0.1% in cruise sfc, 16% in compressor stall margin and 10% in compressor stator angle margin. The New Front Mount hardware successfully completed 35,000 simulated flight cycles endurance testing.

  20. Do Business Communication Courses Improve Student Performance in Introductory Marketing?

    Science.gov (United States)

    Marcal, Leah E.; Hennessey, Judith E.; Curren, Mary T.; Roberts, William W.

    2005-01-01

    In this study, the authors investigated whether completion of a business communications course improved student performance in an introductory marketing management course. Regression analysis indicated that students who completed the communications course received higher grades than the otherwise comparable students. In addition, marketing majors…

  1. Improvements in magnetic bearing performance for flywheel energy storage

    Science.gov (United States)

    Plant, David P.; Anand, Davinder K.; Kirk, James A.; Calomeris, Anthony J.; Romero, Robert L.

    1988-01-01

    The paper considers the development of a 500-Watt-hour magnetically suspended flywheel stack energy storage system. The work includes hardware testing results from a stack flywheel energy storage system, improvements in the area of noncontacting displacement transducers, and performance enhancements of magnetic bearings. Experimental results show that a stack flywheel energy storage system is feasible technology.

  2. 48 CFR 970.5203-2 - Performance improvement and collaboration.

    Science.gov (United States)

    2010-10-01

    ..., scientific and technical, security, business and administrative, and any other areas of performance in the... be of benefit in resolving common issues, in confronting common problems, or in reducing costs of... in the communication of the success of improvements to other management and operating contractors...

  3. Research efforts to improve performance of production systems

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to solve the problem of low efficiency of production systems, a lot of work has been done. The research efforts to improve the performance of production systems are summed up here and future research directions are discussed at last.

  4. Coaching as a Performance Improvement Tool at School

    Science.gov (United States)

    Yirci, Ramazan; Karakose, Turgut; Kocabas, Ibrahim

    2016-01-01

    The purpose of this study is to examine the current literature and have an insight about coaching as a performance improvement tool at school. In today's world, schools have to survive and keep their organizational success in the highest level because of the high expectations from school stakeholders. Taking place in such a fierce competitive…

  5. Erythropoietin improves operant conditioning and stability of cognitive performance in mice

    Directory of Open Access Journals (Sweden)

    Ehrenreich Hannelore

    2009-07-01

    Full Text Available Abstract Background Executive functions, learning and attention are imperative facets of cognitive performance, affected in many neuropsychiatric disorders. Recently, we have shown that recombinant human erythropoietin improves cognitive functions in patients with chronic schizophrenia, and that it leads in healthy mice to enhanced hippocampal long-term potentiation, an electrophysiological correlate of learning and memory. To create an experimental basis for further mechanistic insight into erythropoietin-modulated cognitive processes, we employed the Five Choice Serial Reaction Time Task. This procedure allows the study of the effects of erythropoietin on discrete processes of learning and attention in a sequential fashion. Results Male mice were treated for 3 weeks with erythropoietin (5,000 IU/kg versus placebo intraperitoneally every other day, beginning at postnatal day 28. After termination of treatment, mice were started on the Five Choice Serial Reaction Time Task, with daily training and testing extending to about 3 months. Overall, a significantly higher proportion of erythropoietin-treated mice finished the task, that is, reached the criteria of adequately reacting to a 1.0 sec flash light out of five arbitrarily appearing choices. During acquisition of this capability, that is, over almost all sequential training phases, learning readouts (magazine training, operant and discriminant learning, stability of performance were superior in erythropoietin-treated versus control mice. Conclusion Early erythropoietin treatment leads to lasting improvement of cognitive performance in healthy mice. This finding should be exploited in novel treatment strategies for brain diseases.

  6. Improving the performance of a filling line based on simulation

    Science.gov (United States)

    Jasiulewicz-Kaczmarek, M.; Bartkowiak, T.

    2016-08-01

    The paper describes the method of improving performance of a filling line based on simulation. This study concerns a production line that is located in a manufacturing centre of a FMCG company. A discrete event simulation model was built using data provided by maintenance data acquisition system. Two types of failures were identified in the system and were approximated using continuous statistical distributions. The model was validated taking into consideration line performance measures. A brief Pareto analysis of line failures was conducted to identify potential areas of improvement. Two improvements scenarios were proposed and tested via simulation. The outcome of the simulations were the bases of financial analysis. NPV and ROI values were calculated taking into account depreciation, profits, losses, current CIT rate and inflation. A validated simulation model can be a useful tool in maintenance decision-making process.

  7. Improving Learning Performance with Happiness by Interactive Scenarios

    Directory of Open Access Journals (Sweden)

    Chi-Hung Chuang

    2014-01-01

    Full Text Available Recently, digital learning has attracted a lot of researchers to improve the problems of learning carelessness, low learning ability, lack of concentration, and difficulties in comprehending the logic of math. In this study, a digital learning system based on Kinect somatosensory system is proposed to make children and teenagers happily learn in the course of the games and improve the learning performance. We propose two interactive geometry and puzzle games. The proposed somatosensory games can make learners feel curious and raise their motivation to find solutions for boring problems via abundant physical expressions and interactive operations. The players are asked to select particular operation by gestures and physical expressions within a certain time. By doing so, the learners can feel the fun of game playing and train their logic ability before they are aware. Experimental results demonstrate that the proposed somatosensory system can effectively improve the students’ learning performance.

  8. TCP TRAFFIC PERFORMANCE IMPROVING IN LTE-A NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Yang Bo; Wu Weimin; Zhu Guangxi; Yu Hongtao

    2013-01-01

    This paper presents a novel way to improve Transmission Control Protocol (TCP) performance of the users at the edge areas of the macro cells in Long Term Evolution Advanced (LTE-A) systems.Previous works on improving wireless TCP performance are reviewed and current considerations on TCP in LTE-A are explained.Howev5r,those solutions are neither too complex nor limited to some presuppositions which are too restricting for the deployment of LTE-A networks.In this paper a substituted TCP acknowledgement transmission scheme based on Automatic Repeat reQuest (ARQ) information in layer 2 is proposed.The simulation result shows that the proposed method can reduce the delay and improve the throughput of the edging users of the cell,as well as reducing radio resources in LTE-A macro cells.

  9. An improved multilevel fuzzy comprehensive evaluation algorithm for security performance

    Institute of Scientific and Technical Information of China (English)

    LI Ling-juan; SHEN Ling-tong

    2006-01-01

    It is of great importance to take various factors into account when evaluating the network security performance.Multilevel fuzzy comprehensive evaluation is a relatively valid method. However, the traditional multilevel fuzzy comprehensive evaluation algorithm relies on the expert's knowledge and experiences excessively, and the result of the evaluation is usually less accurate. In this article, an improved multilevel fuzzy comprehensive evaluation algorithm, based on fuzzy sets core and entropy weight is presented. Furthermore, a multilevel fuzzy comprehensive evaluation model of P2P network security performance has also been designed, and the improved algorithm is used to make an instant computation based on the model. The advantages of the improved algorithm can be embodied in comparison with the traditional evaluation algorithm.

  10. Operational Performance Improvements to BRIght Target Explorer Constellation

    Science.gov (United States)

    Choi, Seung Yun

    The BRIght Target Explorer (BRITE)-Constellation is composed of six nano-satellites funded by Austria, Canada, and Poland, and each of them is equipped with an optical telescope that observes stars with visual magnitude +3.5 or brighter. BRITE-Constellation has provided numerous images of bright stars from Low Earth Orbit, which will eventually lead to investigation of origin of the Universe. This thesis presents the contribution of the author to BRITE mission, especially in BRITE Operations. The author performed antenna steering experiments on UniBRITE and BRITE-Toronto, to improve data downlink. To improve scientific data collection from BRITE satellites, the author computed available observation time for multiple targets every orbit, which resulted in collection of twice the amount of scientific data. Also, the author increased the available observation time for each target from 32 minutes to 48 minutes by improving the performance of the star tracker on-board BRITE-Toronto.

  11. Improving Sustainability Performance for Public-Private-Partnership (PPP Projects

    Directory of Open Access Journals (Sweden)

    Liyin Shen

    2016-03-01

    Full Text Available Improving sustainability performance in developing infrastructure projects is an important strategy for pursuing the mission of sustainable development. In recent years, the business model of public-private-partnership (PPP is promoted as an effective approach in developing infrastructure projects. It is considered that the distribution of the contribution on project investment between private and public sectors is one of the key variables affecting sustainability performance of PPP-type projects. This paper examines the impacts of the contribution distribution between public and private sectors on project sustainability performance. A model named the sustainability performance-based evaluation model (SPbEM is developed for assisting the assessment of the level of sustainability performance of PPP projects. The study examines the possibility of achieving better sustainability through proper arrangement of the investment distribution between the two primary sectors in developing PPP-type infrastructure projects.

  12. A Mathematical Model to Improve the Performance of Logistics Network

    Directory of Open Access Journals (Sweden)

    Muhammad Izman Herdiansyah

    2012-01-01

    Full Text Available The role of logistics nowadays is expanding from just providing transportation and warehousing to offering total integrated logistics. To remain competitive in the global market environment, business enterprises need to improve their logistics operations performance. The improvement will be achieved when we can provide a comprehensive analysis and optimize its network performances. In this paper, a mixed integer linier model for optimizing logistics network performance is developed. It provides a single-product multi-period multi-facilities model, as well as the multi-product concept. The problem is modeled in form of a network flow problem with the main objective to minimize total logistics cost. The problem can be solved using commercial linear programming package like CPLEX or LINDO. Even in small case, the solver in Excel may also be used to solve such model.Keywords: logistics network, integrated model, mathematical programming, network optimization

  13. USING CISCO NETWORK COMPONENTS TO IMPROVE NIDPS PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Waleed Bul’ajoul

    2016-08-01

    Full Text Available Network Intrusion Detection and Prevention Systems (NIDPSs are used to detect, prevent and report evidence of attacks and malicious traffic. Our paper presents a study where we used open source NIDPS software. We show that NIDPS detection performance can be weak in the face of high-speed and high-load traffic in terms of missed alerts and missed logs. To counteract this problem, we have proposed and evaluated a solution that utilizes QoS, queues and parallel technologies in a multi-layer Cisco Catalyst Switch to increase NIDPSs detection performance. Our approach designs a novel QoS architecture to organise and improve throughput-forwardplan traffic in a layer 3 switch in order to improve NIDPS performance.

  14. Attention alters the appearance of motion coherence.

    Science.gov (United States)

    Liu, Taosheng; Fuller, Stuart; Carrasco, Marisa

    2006-12-01

    Selective attention enhances visual information processing, as measured by behavioral performance and neural activity. However, little is known about its effects on subjective experience. Here, we investigated the effect of transient (exogenous) attention on the appearance of visual motion, using a psychophysical procedure that directly measures appearance and controls for response bias. Observers viewed pairs of moving dot patterns and reported the motion direction of the more coherent pattern. Directing attention (via a peripheral precue) to a stimulus location increased its perceived coherence level and improved performance on a direction discrimination task. In a control experiment, we ruled out response bias by lengthening the time interval between the cue and the stimuli, so that the effect of transient attention could no longer be exerted. Our results are consistent with those of neurophysiological studies showing that attention modulates motion processing and provide evidence of a subjective perceptual correlate of attention, with a concomitant effect on performance.

  15. Improving the Performance of the Extreme-scale Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Engelmann, Christian [ORNL; Naughton III, Thomas J [ORNL

    2014-01-01

    Investigating the performance of parallel applications at scale on future high-performance computing (HPC) architectures and the performance impact of different architecture choices is an important component of HPC hardware/software co-design. The Extreme-scale Simulator (xSim) is a simulation-based toolkit for investigating the performance of parallel applications at scale. xSim scales to millions of simulated Message Passing Interface (MPI) processes. The overhead introduced by a simulation tool is an important performance and productivity aspect. This paper documents two improvements to xSim: (1) a new deadlock resolution protocol to reduce the parallel discrete event simulation management overhead and (2) a new simulated MPI message matching algorithm to reduce the oversubscription management overhead. The results clearly show a significant performance improvement, such as by reducing the simulation overhead for running the NAS Parallel Benchmark suite inside the simulator from 1,020\\% to 238% for the conjugate gradient (CG) benchmark and from 102% to 0% for the embarrassingly parallel (EP) and benchmark, as well as, from 37,511% to 13,808% for CG and from 3,332% to 204% for EP with accurate process failure simulation.

  16. Policy Decomposition for Evaluation Performance Improvement of PDP

    Directory of Open Access Journals (Sweden)

    Fan Deng

    2014-01-01

    Full Text Available In conventional centralized authorization models, the evaluation performance of policy decision point (PDP decreases obviously with the growing numbers of rules embodied in a policy. Aiming to improve the evaluation performance of PDP, a distributed policy evaluation engine called XDPEE is presented. In this engine, the unicity of PDP in the centralized authorization model is changed by increasing the number of PDPs. A policy should be decomposed into multiple subpolicies each with fewer rules by using a decomposition method, which can have the advantage of balancing the cost of subpolicies deployed to each PDP. Policy decomposition is the key problem of the evaluation performance improvement of PDPs. A greedy algorithm with O(nlgn time complexity for policy decomposition is constructed. In experiments, the policy of the LMS, VMS, and ASMS in real applications is decomposed separately into multiple subpolicies based on the greedy algorithm. Policy decomposition guarantees that the cost of subpolicies deployed to each PDP is equal or approximately equal. Experimental results show that (1 the method of policy decomposition improves the evaluation performance of PDPs effectively and that (2 the evaluation time of PDPs reduces with the growing numbers of PDPs.

  17. Improving public administration performance demands investment in human resources

    Directory of Open Access Journals (Sweden)

    Maja Klun

    2008-06-01

    Full Text Available The paper emphasizes that investments in human resources are one of the important factors for improving public sector performance. In strategic papers of Slovenian government and during the reform process of public administration, government stressed out that human resources are one of the most important factors for improving performance. This is originating point of research. The main hypothesis of presented research is that investments in human resources improve efficiency and effectiveness of public sector. For several reasons explained in the paper, tax administration was chosen to test the hypothesis. We used a number of training participations per employee as an indicator of investments in human resources. For determination of effi ciency and effectiveness, we used selected performance indicators and survey among taxpayers about their satisfaction. The main obstacle of the research is that not long-time series are used for better test of hypothesis since surveys among taxpayers are not regular. The results indicate a positive correlation between training and performance indicators and training and taxpayers’ satisfaction.

  18. Data Mining: A prediction for performance improvement using classification

    CERN Document Server

    Bhardwaj, Brijesh Kumar

    2012-01-01

    Now-a-days the amount of data stored in educational database increasing rapidly. These databases contain hidden information for improvement of students' performance. The performance in higher education in India is a turning point in the academics for all students. This academic performance is influenced by many factors, therefore it is essential to develop predictive data mining model for students' performance so as to identify the difference between high learners and slow learners student. In the present investigation, an experimental methodology was adopted to generate a database. The raw data was preprocessed in terms of filling up missing values, transforming values in one form into another and relevant attribute/ variable selection. As a result, we had 300 student records, which were used for by Byes classification prediction model construction. Keywords- Data Mining, Educational Data Mining, Predictive Model, Classification.

  19. New MEA Materials for Improved DMFC Performance, Durability and Cost

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, James H. [University of North Florida; Campbell, Joseph L. [University of North Florida; Cox, Philip [University of North Florida; Harrington, William J. [University of North Florida

    2013-09-16

    Abstract Project Title: New MEA Materials for Improved DMFC Performance, Durability and Cost The University of North Florida (UNF)--with project partners the University of Florida, Northeastern University, and Johnson Matthey--has recently completed the Department of Energy (DOE) project entitled “New MEA Materials for Improved DMFC Performance, Durability and Cost”. The primary objective of the project was to advance portable fuel cell MEA technology towards the commercial targets as laid out in the DOE R&D roadmap by developing a passive water recovery MEA (membrane electrode assembly). Developers at the University of North Florida identified water management components as an insurmountable barrier to achieving the required system size and weight necessary to achieve the energy density requirements of small portable power applications. UNF developed an innovative “passive water recovery” MEA for direct methanol fuel cells (DMFC) which provides a path to system simplification and optimization. The passive water recovery MEA incorporates a hydrophobic, porous, barrier layer within the cathode electrode, so that capillary pressure forces the water produced at the cathode through holes in the membrane and back to the anode. By directly transferring the water from the cathode to the anode, the balance of plant is very much simplified and the need for heavy, bulky water recovery components is eliminated. At the heart of the passive water recovery MEA is the UNF DM-1 membrane that utilizes a hydrocarbon structure to optimize performance in a DMFC system. The membrane has inherent performance advantages, such as a low methanol crossover (high overall efficiency), while maintaining a high proton conductivity (good electrochemical efficiency) when compared to perfluorinated sulfonic acid membranes such as Nafion. Critically, the membrane provides an extremely low electro-osmotic drag coefficient of approximately one water molecule per proton (versus the 2-3 for

  20. The role of skin conductance level reactivity in the impact of children’s exposure to interparental conflict on their attention performance

    OpenAIRE

    Zemp, Martina; Bodenmann, Guy; Cummings, E. Mark

    2014-01-01

    Previous research suggests that undermining of attention performance might be one decisive underlying mechanism in the link between marital conflict and children's academic maladjustment, but little is known about specific risk patterns in this regard. This study examines, in an experimental approach, the role of children's history of interparental discord and skin conductance level reactivity (SCLR) as moderators in the link between analogue marital conflict exposure and children's attention...

  1. Separation of genetic influences on attention deficit hyperactivity disorder symptoms and reaction time performance from those on IQ

    NARCIS (Netherlands)

    Wood, A. C.; Asherson, P.; van der Meere, J. J.; Kuntsi, J.

    2010-01-01

    Background. Attention deficit hyperactivity disorder (ADHD) shows a strong phenotypic and genetic association with reaction time (RI) variability, considered to reflect lapses in attention. Yet we know little about whether this aetiological pathway is shared with other affected cognitive processes i

  2. Virulent bacterial infection improves aversive learning performance in Drosophila melanogaster.

    Science.gov (United States)

    Babin, Aurélie; Kolly, Sylvain; Kawecki, Tadeusz J

    2014-10-01

    Virulent infections are expected to impair learning ability, either as a direct consequence of stressed physiological state or as an adaptive response that minimizes diversion of energy from immune defense. This prediction has been well supported for mammals and bees. Here, we report an opposite result in Drosophila melanogaster. Using an odor-mechanical shock conditioning paradigm, we found that intestinal infection with bacterial pathogens Pseudomonas entomophila or Erwinia c. carotovora improved flies' learning performance after a 1h retention interval. Infection with P. entomophila (but not E. c. carotovora) also improved learning performance after 5 min retention. No effect on learning performance was detected for intestinal infections with an avirulent GacA mutant of P. entomophila or for virulent systemic (hemocoel) infection with E. c. carotovora. Assays of unconditioned responses to odorants and shock do not support a major role for changes in general responsiveness to stimuli in explaining the changes in learning performance, although differences in their specific salience for learning cannot be excluded. Our results demonstrate that the effects of pathogens on learning performance in insects are less predictable than suggested by previous studies, and support the notion that immune stress can sometimes boost cognitive abilities.

  3. An improved model for TPV performance predictions and optimization

    Science.gov (United States)

    Schroeder, K. L.; Rose, M. F.; Burkhalter, J. E.

    1997-03-01

    Previously a model has been presented for calculating the performance of a TPV system. This model has been revised into a general purpose algorithm, improved in fidelity, and is presented here. The basic model is an energy based formulation and evaluates both the radiant and heat source elements of a combustion based system. Improvements in the radiant calculations include the use of ray tracking formulations and view factors for evaluating various flat plate and cylindrical configurations. Calculation of photocell temperature and performance parameters as a function of position and incident power have also been incorporated. Heat source calculations have been fully integrated into the code by the incorporation of a modified version of the NASA Complex Chemical Equilibrium Compositions and Applications (CEA) code. Additionally, coding has been incorporated to allow optimization of various system parameters and configurations. Several examples cases are presented and compared, and an optimum flat plate emitter/filter/photovoltaic configuration is also described.

  4. An Accurate Link Correlation Estimator for Improving Wireless Protocol Performance

    Directory of Open Access Journals (Sweden)

    Zhiwei Zhao

    2015-02-01

    Full Text Available Wireless link correlation has shown significant impact on the performance of various sensor network protocols. Many works have been devoted to exploiting link correlation for protocol improvements. However, the effectiveness of these designs heavily relies on the accuracy of link correlation measurement. In this paper, we investigate state-of-the-art link correlation measurement and analyze the limitations of existing works. We then propose a novel lightweight and accurate link correlation estimation (LACE approach based on the reasoning of link correlation formation. LACE combines both long-term and short-term link behaviors for link correlation estimation. We implement LACE as a stand-alone interface in TinyOS and incorporate it into both routing and flooding protocols. Simulation and testbed results show that LACE: (1 achieves more accurate and lightweight link correlation measurements than the state-of-the-art work; and (2 greatly improves the performance of protocols exploiting link correlation.

  5. Improvement in performance of main ventilation fan for mines

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, S.N. [Indian School of Mines, Dhanbad (India)

    2007-07-01

    This paper examined methods of improving the performance of main ventilation fans in mines. The basic principles of selecting and operating fans were reviewed, and methods of improving the energy efficiency of fans were evaluated. The study considered issues related to static efficiency, as well as curves and intersection points. Mine resistances were examined in relation to ventilation requirements at different phases of mine development. Flow losses and difficulties in producing accurate mathematical models of ventilation fans were also discussed. Fan operation set-points were reviewed. Details of tests conducted to determine the effects of the number of blades on fan performance were presented. The tests demonstrated the importance of incorporating cowl diffusers and guide vanes within the design of axial flow fans. The advantages of deblading were also discussed. 6 refs.

  6. Does Property Right Transformation Improve Township and Village Enterprises Performance?

    Institute of Scientific and Technical Information of China (English)

    Zhixiong Du; Yoichi Izumida

    2006-01-01

    To date, few observations have been made about the performance improvement that resulted from the property right transformation of the collective-owned township and village enterprises (TVE) in the middle of 1990s. Using data collected from a questionnaire survey on the privatized TVE and their employees, the present paper provides some empirical evidence about this topic, and the analysis suggests that property right transformation has had a positive impact on sample enterprises'performance, including business improvement,employment expansion, incremental investment and contributions to government revenues.The present study concludes that, from a transient viewpoint, the property right transformation has not distorted local governments' intentions to establish TVE in earlier years.

  7. Combined Space and Water Heating: Next Steps to Improved Performance

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States)

    2016-07-13

    A combined space- and water-heating (combi) system uses a high-efficiency direct-vent burner that eliminates safety issues associated with natural draft appliances. Past research with these systems shows that using condensing water heaters or boilers with hydronic air handling units can provide both space and water heating with efficiencies of 90% or higher. Improved controls have the potential to reduce complexity and improve upon the measured performance. This project demonstrates that controls can significantly benefit these first-generation systems. Laboratory tests and daily load/performance models showed that the set point temperature reset control produced a 2.1%-4.3% (20-40 therms/year) savings for storage and hybrid water heater combi systems operated in moderate-load homes.

  8. Using storyboards to make your performance improvement plan come alive.

    Science.gov (United States)

    Pfaadt, M

    1998-01-01

    The key to successfully using storyboarding within the PI plan is to create a storyboard for each activity as it is completed. Our agency waited until JCAHO was almost upon us. The historical preservation of activities as they occur will create an archive of activities for your PI committee and staff as well as for surveyors. The storyboard's second purpose is the communication of activities to the staff. Take the opportunity to use the boards as educational activities for the staff. Performance Improvement can many times be a frightening, or at best frustrating and uncomfortable activity for staff personnel. Bringing the PI plan alive through the use of storyboards accomplishes many goals as well as helps all staff see how Performance Improvement really makes a difference.

  9. Inspiratory muscle training improves 100 and 200 m swimming performance.

    Science.gov (United States)

    Kilding, Andrew E; Brown, Sarah; McConnell, Alison K

    2010-02-01

    Inspiratory muscle training (IMT) has been shown to improve time trial performance in competitive athletes across a range of sports. Surprisingly, however, the effect of specific IMT on surface swimming performance remains un-investigated. Similarly, it is not known whether any ergogenic influence of IMT upon swimming performance is confined to specific race distances. To determine the influence of IMT upon swimming performance over 3 competitive distances, 16 competitive club-level swimmers were assigned at random to either an experimental (pressure threshold IMT) or sham IMT placebo control group. Participants performed a series of physiological and performance tests, before and following 6 weeks of IMT, including (1) an incremental swim test to the limit of tolerance to determine lactate, heart rate and perceived exertion responses; (2) standard measures of lung function (forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow) and maximal inspiratory pressure (MIP); and (3) 100, 200 and 400 m swim time trials. Training utilised a hand-held pressure threshold device and consisted of 30 repetitions, twice per day. Relative to control, the IMT group showed the following percentage changes in swim times: 100 m, -1.70% (90% confidence limits, +/-1.4%), 200 m, -1.5% (+/-1.0), and 400 m, 0.6% (+/-1.2). Large effects were observed for MIP and rates of perceived exertion. In conclusion, 6 weeks of IMT has a small positive effect on swimming performance in club-level trained swimmers in events shorter than 400 m.

  10. Geoelectrical mapping for improved performance of SUDS in clay tills

    DEFF Research Database (Denmark)

    Bockhorn, Britta; Møller, Ingelise; Klint, Knud Erik S.;

    2015-01-01

    geological methods, including borehole soil sample descriptions, one excavation description and a near-surface spear auger-mapping project. The experiments returned a significant correlation of geoelectrical and spear auger-mapped surface sediments. Furthermore, a highly permeable oxidized fracture zone...... in greater depths could be revealed on the 2D geoelectrical profiles. The successful determination of highly permeable zones harbors potential for improved hydraulic performance of infiltration SUDS (sustainable urban drainage systems)....

  11. Towards an Improved Performance Measure for Language Models

    CERN Document Server

    Ueberla, J P

    1997-01-01

    In this paper a first attempt at deriving an improved performance measure for language models, the probability ratio measure (PRM) is described. In a proof of concept experiment, it is shown that PRM correlates better with recognition accuracy and can lead to better recognition results when used as the optimisation criterion of a clustering algorithm. Inspite of the approximations and limitations of this preliminary work, the results are very encouraging and should justify more work along the same lines.

  12. PDMS/PVA composite ferroelectret for improved energy harvesting performance

    Science.gov (United States)

    Shi, J.; Luo, Z.; Zhu, D.; Beeby, S. P.

    2016-11-01

    This paper address the PDMS ferroelectret discharge issue for improved long- term energy harvesting performance. The PDMS/PVA ferroelectret is fabricated using a 3D-printed plastic mould technology and a functional PVA composite layer is introduced. The PDMS/PVA composite ferroelectret achieved 80% piezoelectric coefficient d33 remaining, compared with 40% without the proposed layer over 72 hours. Further, the retained percentage of output voltage is about 73% over 72 hours.

  13. Modeling and Simulation of Ceramic Arrays to Improve Ballistic Performance

    Science.gov (United States)

    2014-04-30

    distribution is Unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT -Develop Modeling and Simulation tools, use Depth of Penetration ( DOP ) as metric...7.62 APM2 -Evaluate SiC tile on Aluminum with material properties from literature -Develop seam designs to improve performance, demonstrate with DOP ...5083, SiC, DoP Expeminets, AutoDyn Sin 16. SECURITY CLASSIFICATION OF: UU a. REPORT b. ABSTRACT c. THIS PAGE 17. LIMITATION OF ABSTRACT UU 18

  14. Smoking Cessation and Improvement in Physical Performance Among Young Men

    Science.gov (United States)

    2015-03-01

    California, to quantify the im pact o f smoking cessation on a measure of aerobic fitness among healthy young men. MILITARY MEDICINE, Vol. 180...Trinick T: Physical activity, physical fitness and respiratory function— exercise and respiratory function. Ir J Med Sci 1999; 168(2): 119-23. 20...improved physical perform ance as a potential motivation to quit sm oking.7-1 Quantifiable measures of cardiopulmonary fitness , such as maximal

  15. Modify AODV Routing Protocol to Improve Motorway Surveillance System Performance

    OpenAIRE

    Layth Abdulkareem Hassnawi; R. Badlishah Ahmad; Abid Yahya

    2012-01-01

    This paper presents an algorithm to modify the Ad Hoc On-Demand Distance Vector (AODV) routing protocol in order to improve the routing performance in motorway surveillance systems. The proposed protocol has all the characteristics of the original AODV routing protocol since it follows all the steps of the route discovery and route maintenance mechanism of the original AODV routing protocol. The Modified AODV (MAODV) is different from the original AODV protocol in that it modifies the origina...

  16. Improved patch antenna performance by using a metamaterial cover

    Institute of Scientific and Technical Information of China (English)

    ZHU Fang-ming; HU Jun

    2007-01-01

    A new patch antenna system with a metamaterial cover is presented in this paper. The impedance, radiation pattern, and directivity of such an antenna are studied. A performance comparison between the conventional patch antenna and the new metamaterial patch antenna is given. The results show that the directivity of the metamaterial patch antenna is significantly improved. The effect of the metamaterial cover's layer numbers on the radiation pattern of the patch antenna is also studied.

  17. Effects of Improvement on Selective Attention: Developing Appropriate Somatosensory Video Game Interventions for Institutional-Dwelling Elderly with Disabilities

    Science.gov (United States)

    Chen, Shang-Ti; Chiang, I-Tsun; Liu, Eric Zhi-Feng; Chang, Maiga

    2012-01-01

    The purpose of this study was to develop appropriate somatosensory video game interventions on enhancing selective attention of institutional-dwelling elderly with disabilities. Fifty-eight participants aged 65[approximately]92 were recruited and divided into four groups, 4-week and 8-week experimental and two control groups, for evaluating the…

  18. Does Long-Term Medication Use Improve the Academic Outcomes of Youth with Attention-Deficit/Hyperactivity Disorder?

    Science.gov (United States)

    Langberg, Joshua M.; Becker, Stephen P.

    2012-01-01

    Youth with Attention-Deficit/Hyperactivity Disorder (ADHD) frequently experience academic impairment, including lower grades than their peers and elevated risk for grade retention and school dropout. Medication is the most commonly used treatment for youth with ADHD, and it is therefore essential to understand the extent to which medication use…

  19. Voluntary attention increases perceived spatial frequency.

    Science.gov (United States)

    Abrams, Jared; Barbot, Antoine; Carrasco, Marisa

    2010-08-01

    Voluntary covert attention selects relevant sensory information for prioritized processing. The behavioral and neural consequences of such selection have been extensively documented, but its phenomenology has received little empirical investigation. Involuntary attention increases perceived spatial frequency (Gobell & Carrasco, 2005), but involuntary attention can differ from voluntary attention in its effects on performance in tasks mediated by spatial resolution (Yeshurun, Montagna, & Carrasco, 2008). Therefore, we ask whether voluntary attention affects the subjective appearance of spatial frequency--a fundamental dimension of visual perception underlying spatial resolution. We used a demanding rapid serial visual presentation task to direct voluntary attention and measured perceived spatial frequency at the attended and unattended locations. Attention increased the perceived spatial frequency of suprathreshold stimuli and also improved performance on a concurrent orientation discrimination task. In the control experiment, we ruled out response bias as an alternative account by using a lengthened interstimulus interval, which allows observers to disengage attention from the cued location. In contrast to the main experiment, the observers showed neither increased perceived spatial frequency nor improved orientation discrimination at the attended location. Thus, this study establishes that voluntary attention increases perceived spatial frequency. This phenomenological consequence links behavioral and neurophysiological studies on the effects of attention.

  20. Alpha neurofeedback training improves SSVEP-based BCI performance

    Science.gov (United States)

    Wan, Feng; Nuno da Cruz, Janir; Nan, Wenya; Wong, Chi Man; Vai, Mang I.; Rosa, Agostinho

    2016-06-01

    Objective. Steady-state visual evoked potential (SSVEP)-based brain-computer interfaces (BCIs) can provide relatively easy, reliable and high speed communication. However, the performance is still not satisfactory, especially in some users who are not able to generate strong enough SSVEP signals. This work aims to strengthen a user’s SSVEP by alpha down-regulating neurofeedback training (NFT) and consequently improve the performance of the user in using SSVEP-based BCIs. Approach. An experiment with two steps was designed and conducted. The first step was to investigate the relationship between the resting alpha activity and the SSVEP-based BCI performance, in order to determine the training parameter for the NFT. Then in the second step, half of the subjects with ‘low’ performance (i.e. BCI classification accuracy <80%) were randomly assigned to a NFT group to perform a real-time NFT, and the rest half to a non-NFT control group for comparison. Main results. The first step revealed a significant negative correlation between the BCI performance and the individual alpha band (IAB) amplitudes in the eyes-open resting condition in a total of 33 subjects. In the second step, it was found that during the IAB down-regulating NFT, on average the subjects were able to successfully decrease their IAB amplitude over training sessions. More importantly, the NFT group showed an average increase of 16.5% in the SSVEP signal SNR (signal-to-noise ratio) and an average increase of 20.3% in the BCI classification accuracy, which was significant compared to the non-NFT control group. Significance. These findings indicate that the alpha down-regulating NFT can be used to improve the SSVEP signal quality and the subjects’ performance in using SSVEP-based BCIs. It could be helpful to the SSVEP related studies and would contribute to more effective SSVEP-based BCI applications.

  1. Improving the performance of the JET Shape Controller

    Energy Technology Data Exchange (ETDEWEB)

    Maviglia, Francesco, E-mail: francesco.maviglia@unirc.it [Consorzio CREATE, Univ. Napoli Federico II - DIETI, 80125 Napoli (Italy); Ariola, Marco [Consorzio CREATE/Dip. di Ing. – Università di Napoli Parthenope, Isola C4, 80143 Naples (Italy); De Tommasi, Gianmaria [Consorzio CREATE, Univ. Napoli Federico II - DIETI, 80125 Napoli (Italy); Lomas, Peter J. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Pironti, Alfredo [Consorzio CREATE, Univ. Napoli Federico II - DIETI, 80125 Napoli (Italy); Rimini, Fernanda G. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Albanese, Raffaele; Ambrosino, Giuseppe [Consorzio CREATE, Univ. Napoli Federico II - DIETI, 80125 Napoli (Italy)

    2015-10-15

    Highlights: • Implementation of reliable simulation tool to minimize experimental time for controller tuning. • Improving the inductive decoupling among JET poloidal field coils. • Improving the performance of the specific controlled variables. • New algorithm used in the majority of JET pulses since January 2014. - Abstract: The JET Shape Controller (SC) uses nine distinct circuits, powering the JET poloidal field coils, to control in real time the coil currents, and the plasma shape, current and position. The control scheme presently used [1] is based on a Multiple Input Multiple Output (MIMO) controller, which is designed to decouple the inductive coupling of the different coils. Achieving such a decoupling, the SC allows the user to tune independently the time response of each circuit. As a matter of fact the intended decoupling algorithm has been incorrectly coded in the JET SC system. This paper describes the modelling and experimental activities performed to correct the code error, and to improve the performance on a subset of the controlled parameters.

  2. Improved ICF implosion performance through precision engineering features

    Science.gov (United States)

    Weber, Christopher

    2016-10-01

    The thin membrane that holds the capsule in-place in the hohlraum is recognized as one of the most significant contributors to reduced performance in indirect drive inertial confinement fusion (ICF) experiments on the National Ignition Facility (NIF). This membrane, known as the ``tent'', seeds a perturbation that is amplified by Rayleigh-Taylor and can rupture the capsule. The ICF program is undertaking a major effort to develop a less damaging capsule support mechanism. Possible alternatives include micron-scale rods spanning the hohlraum width and supporting either the capsule or stiffening the fill-tube, a larger fill-tube to both fill and support the capsule, or a low-density foam layer that protects the capsule from the tent impact. In addition to the challenges presented by nano and microscale engineering, it is difficult to model and experimentally verify improvement from these changes. The 3D nature of the proposed replacements and the radiation shadows they cast on the capsule prohibit direct simulation. Therefore a combination of reduced models and experimental verification are used to set requirements and down-select the options. Ultimately the improved capsule support will be used to repeat a DT-layered implosion and demonstrate improved performance. Work performed under the auspices of the U.S. D.O.E. by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344.

  3. An Approach to Improve the Performance of PM Forecasters.

    Directory of Open Access Journals (Sweden)

    Paulo S G de Mattos Neto

    Full Text Available The particulate matter (PM concentration has been one of the most relevant environmental concerns in recent decades due to its prejudicial effects on living beings and the earth's atmosphere. High PM concentration affects the human health in several ways leading to short and long term diseases. Thus, forecasting systems have been developed to support decisions of the organizations and governments to alert the population. Forecasting systems based on Artificial Neural Networks (ANNs have been highlighted in the literature due to their performances. In general, three ANN-based approaches have been found for this task: ANN trained via learning algorithms, hybrid systems that combine search algorithms with ANNs, and hybrid systems that combine ANN with other forecasters. Independent of the approach, it is common to suppose that the residuals (error series, obtained from the difference between actual series and forecasting, have a white noise behavior. However, it is possible that this assumption is infringed due to: misspecification of the forecasting model, complexity of the time series or temporal patterns of the phenomenon not captured by the forecaster. This paper proposes an approach to improve the performance of PM forecasters from residuals modeling. The approach analyzes the remaining residuals recursively in search of temporal patterns. At each iteration, if there are temporal patterns in the residuals, the approach generates the forecasting of the residuals in order to improve the forecasting of the PM time series. The proposed approach can be used with either only one forecaster or by combining two or more forecasting models. In this study, the approach is used to improve the performance of a hybrid system (HS composed by genetic algorithm (GA and ANN from residuals modeling performed by two methods, namely, ANN and own hybrid system. Experiments were performed for PM2.5 and PM10 concentration series in Kallio and Vallila stations in

  4. Improved rate control for electron-beam evaporation and evaluation of optical performance improvements.

    Science.gov (United States)

    Gevelber, Michael; Xu, Bing; Smith, Douglas

    2006-03-01

    A new deposition-rate-control and electron-beam-gun (e-gun) strategy was developed that significantly reduces the growth-rate variations for e-beam-deposited SiO2 coatings. The resulting improvements in optical performance are evaluated for multilayer bandpass filters. The adverse effect of uneven silica-source depletion on coating spectral performances during long deposition runs is discussed.

  5. Improvement of Interior Ballistic Performance Utilizing Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Hazem El Sadek

    2014-01-01

    Full Text Available This paper investigates the interior ballistic propelling charge design using the optimization methods to select the optimum charge design and to improve the interior ballistic performance. The propelling charge consists of a mixture propellant of seven-perforated granular propellant and one-hole tubular propellant. The genetic algorithms and some other evolutionary algorithms have complex evolution operators such as crossover, mutation, encoding, and decoding. These evolution operators have a bad performance represented in convergence speed and accuracy of the solution. Hence, the particle swarm optimization technique is developed. It is carried out in conjunction with interior ballistic lumped-parameter model with the mixture propellant. This technique is applied to both single-objective and multiobjective problems. In the single-objective problem, the optimization results are compared with genetic algorithm and the experimental results. The particle swarm optimization introduces a better performance of solution quality and convergence speed. In the multiobjective problem, the feasible region provides a set of available choices to the charge’s designer. Hence, a linear analysis method is adopted to give an appropriate set of the weight coefficients for the objective functions. The results of particle swarm optimization improved the interior ballistic performance and provided a modern direction for interior ballistic propelling charge design of guided projectile.

  6. Multi-focal Vision and Gaze Control Improve Navigation Performance

    Directory of Open Access Journals (Sweden)

    Kolja Kühnlenz

    2012-05-01

    Full Text Available Multi‐focal vision systems comprise cameras with various fields of view and measurement accuracies. This article presents a multi‐focal approach to localization and mapping of mobile robots with active vision. An implementation of the novel concept is done considering a humanoid robot navigation scenario where the robot is visually guided through a structured environment with several landmarks. Various embodiments of multi‐focal vision systems are investigated and the impact on navigation performance is evaluated in comparison to a conventional mono‐focal stereo set‐up. The comparative studies clearly show the benefits of multi‐focal vision for mobile robot navigation: flexibility to assign the different available sensors optimally in each situation, enhancement of the visible field, higher localization accuracy, and, thus, better task performance, i.e. path following behavior of the mobile robot. It is shown that multi‐focal vision may strongly improve navigation performance.

  7. Multi-focal Vision and Gaze Control Improve Navigation Performance

    Directory of Open Access Journals (Sweden)

    Kolja Kuehnlenz

    2008-11-01

    Full Text Available Multi-focal vision systems comprise cameras with various fields of view and measurement accuracies. This article presents a multi-focal approach to localization and mapping of mobile robots with active vision. An implementation of the novel concept is done considering a humanoid robot navigation scenario where the robot is visually guided through a structured environment with several landmarks. Various embodiments of multi-focal vision systems are investigated and the impact on navigation performance is evaluated in comparison to a conventional mono-focal stereo set-up. The comparative studies clearly show the benefits of multi-focal vision for mobile robot navigation: flexibility to assign the different available sensors optimally in each situation, enhancement of the visible field, higher localization accuracy, and, thus, better task performance, i.e. path following behavior of the mobile robot. It is shown that multi-focal vision may strongly improve navigation performance.

  8. Perspectives on containment performance improvement based on the IPEs

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, J.R.; Lin, C.C.; Pratt, W.T. [Brookhaven National Lab., Upton, NY (United States)] [and others

    1995-04-01

    Generic Letter 88-20, {open_quotes}Individual Plant Examination (IPE) for Severe Accident Vulnerabilities - 10CFR 50.54(f),{close_quotes} was issued by the NRC on November 23, 1988. In addition to assessing the core damage frequency from severe accidents, licensees were requested to report the results of their analyses regarding containment performance. Supplements to the Generic Letter forwarded technical insights obtained by the NRC staff through its Containment Performance Improvement (CPI) program. At this time, most of the IPEs have been submitted by the licensees. In a follow-on effort to support regulatory activities, the NRC staff with assistance from Brookhaven National Laboratory, has initiated a program involving a global examination of the containment performance results documented in the IPEs. The objective is to identify insights of potential generic safety significance relative to plant design, operation and maintenance, as well as to assess response to the previously forwarded CPI insights. The containment performance results of the IPEs are being categorized for commonalities and differences for different reactor and containment types. Preliminary results show that not only differences in plant design but also the methods, data, boundary conditions, and assumptions used in the different IPEs have a major impact on the containment performance results obtained. This paper presents preliminary results regarding the differences in containment performance observed in the IPEs and discusses some of the underlying reasons for these differences.

  9. Selective Attention and Attention Switching: Towards a Unified Developmental Approach

    Science.gov (United States)

    Hanania, Rima; Smith, Linda B.

    2010-01-01

    We review and relate two literatures on the development of attention in children: one concerning flexible attention switching and the other concerning selective attention. The first is a growing literature on preschool children's performances in an attention-switching task indicating that children become more flexible in their attentional control…

  10. Effect of attention control on sustained attention during induced anxiety.

    Science.gov (United States)

    Grillon, Christian; Robinson, Oliver J; Mathur, Ambika; Ernst, Monique

    2016-01-01

    Anxiety has wide-reaching and complex effects on cognitive performance. Although it can intrude on cognition and interfere with performance, it can also facilitate information processing and behavioural responses. In a previous study, we showed that anxiety induced by threat of shock facilitates performance on the Sustained Attention to Response Task, a vigilance test, which probes response inhibition to infrequent nogo stimuli. The present study sought to identify factors that may have contributed to such improved performance, including on- and off-task thinking (assessed with thought probes) and individual differences in attention control, as measured with the Attention Control Scale. Replicating our prior finding, we showed that shock threat significantly reduced errors of commission on the nogo trials. However, we extended this finding in demonstrating that this effect was driven by subjects with low attention control. We therefore confirm that anxiety increases inhibitory control of prepotent responses--a mechanism which is adaptive under threat--and show that this effect is greater in those who rely more upon such prepotent responding, i.e., those with low attentional control.

  11. Reward Contingencies Improve Goal-Directed Behavior by Enhancing Posterior Brain Attentional Regions and Increasing Corticostriatal Connectivity in Cocaine Addicts

    Science.gov (United States)

    Rosell-Negre, Patricia; Bustamante, Juan-Carlos; Fuentes-Claramonte, Paola; Costumero, Víctor; Llopis-Llacer, Juan-José; Barrós-Loscertales, Alfonso

    2016-01-01

    The dopaminergic system provides the basis for the interaction between motivation and cognition. It is triggered by the possibility of obtaining rewards to initiate the neurobehavioral adaptations necessary to achieve them by directing the information from motivational circuits to cognitive and action circuits. In drug addiction, the altered dopamine (DA) modulation of the meso-cortico-limbic reward circuitry, such as the prefrontal cortex (PFC), underlies the disproportionate motivational value of drug use at the expense of other non-drug reinforcers and the user’s loss of control over his/her drug intake. We examine how the magnitude of the reward affects goal-directed processes in healthy control (HC) subjects and abstinent cocaine dependent (ACD) patients by using functional magnetic resonance imaging (fMRI) during a counting Stroop task with blocked levels of monetary incentives of different magnitudes (€0, €0.01, €0.5, €1 or €1.5). Our results showed that increasing reward magnitude enhances (1) performance facilitation in both groups; (2) left dorsolateral prefrontal cortex (DLPFC) activity in HC and left superior occipital cortex activity in ACD; and (3) left DLPFC and left putamen connectivity in ACD compared to HC. Moreover, we observed that (4) dorsal striatal and pallidum activity was associated with craving and addiction severity during the parametric increases in the monetary reward. In conclusion, the brain response to gradients in monetary value was different in HC and ACD, but both groups showed improved task performance due to the possibility of obtaining greater monetary rewards. PMID:27907134

  12. Low-arousal speech noise improves performance in N-back task: an ERP study.

    Directory of Open Access Journals (Sweden)

    Longzhu Han

    Full Text Available The relationship between noise and human performance is a crucial topic in ergonomic research. However, the brain dynamics of the emotional arousal effects of background noises are still unclear. The current study employed meaningless speech noises in the n-back working memory task to explore the changes of event-related potentials (ERPs elicited by the noises with low arousal level vs. high arousal level. We found that the memory performance in low arousal condition were improved compared with the silent and the high arousal conditions; participants responded more quickly and had larger P2 and P3 amplitudes in low arousal condition while the performance and ERP components showed no significant difference between high arousal and silent conditions. These findings suggested that the emotional arousal dimension of background noises had a significant influence on human working memory performance, and that this effect was independent of the acoustic characteristics of noises (e.g., intensity and the meaning of speech materials. The current findings improve our understanding of background noise effects on human performance and lay the ground for the investigation of patients with attention deficits.

  13. Clinical performance feedback and quality improvement opportunities for perioperative physicians

    Directory of Open Access Journals (Sweden)

    Kaye AD

    2014-05-01

    Full Text Available Alan David Kaye,1 Olutoyin J Okanlawon,2 Richard D Urman21Department of Anesthesiology, Louisiana State University School of Medicine, New Orleans, LA, 2Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Boston MA, USAAbstract: Clinical performance feedback is an important component of the ongoing development and education of health care practitioners. For physicians, feedback about their clinical practice and outcomes is central to developing both confidence and competence at all stages of their medical careers. Cultural and financial infrastructures need to be in place, and the concept of feedback needs to be readily embraced and encouraged by clinical leadership and other stakeholders. The "buy-in" includes the expectation and view that feedback occurs on a routine basis, and those engaged in the process are both encouraged to participate and held accountable. Feedback must be part of an overarching quality improvement and physician education agenda; it is not meant to be an isolated, fragmented initiative that is typically undermined by lack of resources or systemic barriers to gaining improvement within programs. Effective feedback should be an integral part of clinical practice. Anesthesiologists and other perioperative physicians are identifying specialty-specific indicators that can be used when creating a broader quality improvement agenda. Placing a more immediate formal feedback strategy that focuses on goal-oriented behavior is rapidly becoming a mainstay. Physicians may use their individual feedback reports for reflection and designing personal development plans as lifelong learners and leaders in improving patient care.Keywords: physician education, outcomes measurement, performance improvement, anesthesiology

  14. Criterion-based (proficiency) training to improve surgical performance.

    Science.gov (United States)

    Fried, Marvin P; Kaye, Rachel J; Gibber, Marc J; Jackman, Alexis H; Paskhover, Boris P; Sadoughi, Babak; Schiff, Bradley; Fraioli, Rebecca E; Jacobs, Joseph B

    2012-11-01

    OBJECTIVE To investigate whether training otorhinolaryngology residents to criterion performance levels (proficiency) on the Endoscopic Sinus Surgery Simulator produces individuals whose performance in the operating room is at least equal to those who are trained by performing a fixed number of surgical procedures. DESIGN Prospective cohort. SETTING Two academic medical centers in New York City. PARTICIPANTS Otorhinolaryngology junior residents composed of 8 experimental subjects and 6 control subjects and 6 attending surgeons. INTERVENTION Experimental subjects achieved benchmark proficiency criteria on the Endoscopic Sinus Surgery Simulator; control subjects repeated the surgical procedure twice. MAIN OUTCOME MEASURES Residents completed validated objective tests to assess baseline abilities. All subjects were videotaped performing an initial standardized surgical procedure. Residents were videotaped performing a final surgery. Videotapes were assessed for metrics by an expert panel. RESULTS Attendings outperformed the residents in most parameters on the initial procedure. Experimental and attending groups outperformed controls in some parameters on the final procedure. There was no difference between resident groups in initial performance, but the experimental subjects outperformed the control subjects in navigation in the final procedure. Most important, there was no difference in final performance between subgroups of the experimental group on the basis of the number of trials needed to attain proficiency. CONCLUSIONS Simulator training can improve resident technical skills so that each individual attains a proficiency level, despite the existence of an intrinsic range of abilities. This proficiency level translates to at least equal, if not superior, operative performance compared with that of current conventional training with finite repetition of live surgical procedures.

  15. Towards Effective Educational Politics through Improving the Performance Measurement System

    Directory of Open Access Journals (Sweden)

    Tuuli Reisberg

    2013-01-01

    Full Text Available Educational field is impelled to increase performance and quality, financial discipline, strategic behaviour and its goals in order to enhance “effectiveness”. As a result the incorporation of private sector management practices into the educational field is taking place. But it is important to notice that a proliferation of private managerial practices into the educational field goes along with a conflict-laden and contradictory process. Education provides an important area of implementation for techniques of performance evaluation aimed at improving the performance of public services. One of the most common conceptual frameworks in measuring organisational performance takes the form of a production function where the educational institution is seen as analogous to a company transforming inputs into outputs and outcomes through a production process. But the problems and the vagueness in determining educational system’s inputs, outputs and outcomes cause difficulties in making political decisions and that is why clear policy prescriptions have been difficult to derive. The purpose of this article is to create a discussion whether performance measurement should be a part of decision-making in educational politics. The authors debate about incorporating private sector management practices into the educational field. The debate is based on the example of evaluating the social impact in the educational field and the performance of teachers’ work in the educational system. The article consists of three parts. Firstly, the theoretical background of the performance measurement in educational field is discussed. Secondly, the important criteria for performance measurement design and political issues are argued. Thirdly, the evaluated shortcomings in Estonian educational organisations, which restrict them to be effective, are brought out. Relieving some of these shortcomings could be in authority of Estonian educational politics.

  16. The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness.

    Science.gov (United States)

    Giesbrecht, T; Rycroft, J A; Rowson, M J; De Bruin, E A

    2010-12-01

    The non-proteinic amino acid L-theanine and caffeine, a methylxanthine derivative, are naturally occurring ingredients in tea. The present study investigated the effect of a combination of 97 mg L-theanine and 40 mg caffeine as compared to placebo treatment on cognitive performance, alertness, blood pressure, and heart rate in a sample of young adults (n = 44). Cognitive performance, self-reported mood, blood pressure, and heart rate were measured before L-theanine and caffeine administration (i.e. at baseline) and 20 min and 70 min thereafter. The combination of moderate levels of L-theanine and caffeine significantly improved accuracy during task switching and self-reported alertness (both P cognitive tasks, such as visual search, choice reaction times, or mental rotation. The present results suggest that 97 mg of L-theanine in combination with 40 mg of caffeine helps to focus attention during a demanding cognitive task.

  17. Methylphenidate improves prefrontal cortical cognitive function through α2 adrenoceptor and dopamine D1 receptor actions: Relevance to therapeutic effects in Attention Deficit Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Dudley Anne G

    2005-04-01

    Full Text Available Abstract Background Methylphenidate (MPH is the classic treatment for Attention Deficit Hyperactivity Disorder (ADHD, yet the mechanisms underlying its therapeutic actions remain unclear. Recent studies have identified an oral, MPH dose regimen which when given to rats produces drug plasma levels similar to those measured in humans. The current study examined the effects of these low, orally-administered doses of MPH in rats performing a delayed alternation task dependent on prefrontal cortex (PFC, a brain region that is dysfunctional in ADHD, and is highly sensitive to levels of catecholamines. The receptor mechanisms underlying the enhancing effects of MPH were explored by challenging the MPH response with the noradrenergic α2 adrenoceptor antagonist, idazoxan, and the dopamine D1 antagonist, SCH23390. Results MPH produced an inverted U dose response whereby moderate doses (1.0–2.0 mg/kg, p.o. significantly improved delayed alternation performance, while higher doses (2.0–3.0 mg/kg, p.o. produced perseverative errors in many animals. The enhancing effects of MPH were blocked by co-administration of either the α2 adrenoceptor antagonist, idazoxan, or the dopamine D1 antagonist, SCH23390, in doses that had no effect on their own. Conclusion The administration of low, oral doses of MPH to rats has effects on PFC cognitive function similar to those seen in humans and patients with ADHD. The rat can thus be used as a model for examination of neural mechanisms underlying the therapeutic effects of MPH on executive functions in humans. The efficacy of idazoxan and SCH23390 in reversing the beneficial effects of MPH indicate that both noradrenergic α2 adrenoceptor and dopamine D1 receptor stimulation contribute to cognitive-enhancing effects of MPH.

  18. Improving the photovoltaic performance of perovskite solar cells with acetate.

    Science.gov (United States)

    Zhao, Qian; Li, G R; Song, Jian; Zhao, Yulong; Qiang, Yinghuai; Gao, X P

    2016-12-09

    In an all-solid-state perovskite solar cell, methylammonium lead halide film is in charge of generating photo-excited electrons, thus its quality can directly influence the final photovoltaic performance of the solar cell. This paper accentuates a very simple chemical approach to improving the quality of a perovskite film with a suitable amount of acetic acid. With introduction of acetate ions, a homogeneous, continual and hole-free perovskite film comprised of high-crystallinity grains is obtained. UV-visible spectra, steady-state and time-resolved photoluminescence (PL) spectra reveal that the obtained perovskite film under the optimized conditions shows a higher light absorption, more efficient electron transport, and faster electron extraction to the adjoining electron transport layer. The features result in the optimized perovskite film can provide an improved short-circuit current. The corresponding solar cells with a planar configuration achieves an improved power conversion efficiency of 13.80%, and the highest power conversion efficiency in the photovoltaic measurements is up to 14.71%. The results not only provide a simple approach to optimizing perovskite films but also present a novel angle of view on fabricating high-performance perovskite solar cells.

  19. Improving the photovoltaic performance of perovskite solar cells with acetate

    Science.gov (United States)

    Zhao, Qian; Li, G. R.; Song, Jian; Zhao, Yulong; Qiang, Yinghuai; Gao, X. P.

    2016-12-01

    In an all-solid-state perovskite solar cell, methylammonium lead halide film is in charge of generating photo-excited electrons, thus its quality can directly influence the final photovoltaic performance of the solar cell. This paper accentuates a very simple chemical approach to improving the quality of a perovskite film with a suitable amount of acetic acid. With introduction of acetate ions, a homogeneous, continual and hole-free perovskite film comprised of high-crystallinity grains is obtained. UV-visible spectra, steady-state and time-resolved photoluminescence (PL) spectra reveal that the obtained perovskite film under the optimized conditions shows a higher light absorption, more efficient electron transport, and faster electron extraction to the adjoining electron transport layer. The features result in the optimized perovskite film can provide an improved short-circuit current. The corresponding solar cells with a planar configuration achieves an improved power conversion efficiency of 13.80%, and the highest power conversion efficiency in the photovoltaic measurements is up to 14.71%. The results not only provide a simple approach to optimizing perovskite films but also present a novel angle of view on fabricating high-performance perovskite solar cells.

  20. New MEA Materials for Improved DMFC Performance, Durability and Cost

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, James H. [University of North Florida; Campbell, Joseph L. [University of North Florida; Cox, Philip [University of North Florida; Harrington, William J. [University of North Florida

    2013-09-16

    Abstract Project Title: New MEA Materials for Improved DMFC Performance, Durability and Cost The University of North Florida (UNF)--with project partners the University of Florida, Northeastern University, and Johnson Matthey--has recently completed the Department of Energy (DOE) project entitled “New MEA Materials for Improved DMFC Performance, Durability and Cost”. The primary objective of the project was to advance portable fuel cell MEA technology towards the commercial targets as laid out in the DOE R&D roadmap by developing a passive water recovery MEA (membrane electrode assembly). Developers at the University of North Florida identified water management components as an insurmountable barrier to achieving the required system size and weight necessary to achieve the energy density requirements of small portable power applications. UNF developed an innovative “passive water recovery” MEA for direct methanol fuel cells (DMFC) which provides a path to system simplification and optimization. The passive water recovery MEA incorporates a hydrophobic, porous, barrier layer within the cathode electrode, so that capillary pressure forces the water produced at the cathode through holes in the membrane and back to the anode. By directly transferring the water from the cathode to the anode, the balance of plant is very much simplified and the need for heavy, bulky water recovery components is eliminated. At the heart of the passive water recovery MEA is the UNF DM-1 membrane that utilizes a hydrocarbon structure to optimize performance in a DMFC system. The membrane has inherent performance advantages, such as a low methanol crossover (high overall efficiency), while maintaining a high proton conductivity (good electrochemical efficiency) when compared to perfluorinated sulfonic acid membranes such as Nafion. Critically, the membrane provides an extremely low electro-osmotic drag coefficient of approximately one water molecule per proton (versus the 2-3 for

  1. Game elements improve performance in a working memory training task

    Directory of Open Access Journals (Sweden)

    Manuel Ninaus

    2015-02-01

    Full Text Available The utilization of game elements in a non-game context is currently used in a vast range of different domains. However, research on game elements’ effects in cognitive tasks is still sparse. Thus, in this study we implemented three game elements, namely, progress bar, level indicator, and a thematic setting, in a working memory training task. We evaluated the impact of game elements on user performance and perceived state of flow when compared to a conventional version of the task. Participants interacting with game elements showed higher scores in the working memory training task than participants from a control group who completed the working memory training task without the game elements. Moreover, game elements facilitated the individuals’ performance closer to their maximum working memory capacity. Finally, the perceived flow did not differ between the two groups, which indicates that game elements can induce better performance without changing the perception of being “in the zone”, that is without an increase in anxiety or boredom. This empirical study indicates that certain game elements can improve the performance and efficiency in a working memory task by increasing users’ ability and willingness to train at their optimal performance level. 

  2. Attention Economies

    OpenAIRE

    Falkinger, Josef

    2003-01-01

    Attracting attention is a basic feature of economic life but no standard economic problem. A new theoretical model is developed which describes the general structure of competition for attention and characterizes equilibria. The exogenous fundamentals of an attention economy are the space of receiving subjects with their attention capacity, and the potential set of competing companies (senders) with their radiation technologies. The endogenous variables explained by the theory are equilibrium...

  3. Improving Software Performance in the Compute Unified Device Architecture

    Directory of Open Access Journals (Sweden)

    Alexandru PIRJAN

    2010-01-01

    Full Text Available This paper analyzes several aspects regarding the improvement of software performance for applications written in the Compute Unified Device Architecture CUDA. We address an issue of great importance when programming a CUDA application: the Graphics Processing Unit’s (GPU’s memory management through ranspose ernels. We also benchmark and evaluate the performance for progressively optimizing a transposing matrix application in CUDA. One particular interest was to research how well the optimization techniques, applied to software application written in CUDA, scale to the latest generation of general-purpose graphic processors units (GPGPU, like the Fermi architecture implemented in the GTX480 and the previous architecture implemented in GTX280. Lately, there has been a lot of interest in the literature for this type of optimization analysis, but none of the works so far (to our best knowledge tried to validate if the optimizations can apply to a GPU from the latest Fermi architecture and how well does the Fermi architecture scale to these software performance improving techniques.

  4. Terahertz quantum-well photodetectors: Design, performance, and improvements

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S., E-mail: phybuff@sjtu.edu.cn; Wang, T. M.; Hao, M. R.; Yang, Y.; Zhang, Y. H.; Shen, W. Z.; Liu, H. C. [Department of Physics and Astronomy, Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200240 (China)

    2013-11-21

    Theoretical studies and numerical simulations on design, performance, and improvements of terahertz quantum-well photodetector (THz QWP) are presented. In the first part of this paper, we discuss the device band structure resulting from a self-consistent solution and simulation results. First, the temperature dependence of device characteristics is analyzed. Next, we deduce the condition of optimal doping concentration for maximizing dark current limited detectivity D{sub det}* when QWP is lightly doped. Accordingly, unlike in previously published reports, doping concentration is not fixed and is selected by the above condition. In the second part of this paper, we propose two schemes for improving operation temperature. The first is to incorporate an optical antenna which focuses incident THz wave. Numerical results show that the QWP with peak frequency higher than 5.5 THz is expected to achieve background-noise-limited performance at 77 K or above when employing a 10{sup 6} times enhancement antenna. The second scheme is to use a laser as the signal source to achieve photon-noise-limited performance (PLIP) at high temperatures. Simulations show that when operating below critical temperature QWPs in the range of 1 ∼ 7 THz can reach PLIP under practical illumination intensities.

  5. Combined glucose ingestion and mouth rinsing improves sprint cycling performance.

    Science.gov (United States)

    Chong, Edwin; Guelfi, Kym J; Fournier, Paul A

    2014-12-01

    This study investigated whether combined ingestion and mouth rinsing with a carbohydrate solution could improve maximal sprint cycling performance. Twelve competitive male cyclists ingested 100 ml of one of the following solutions 20 min before exercise in a randomized double-blinded counterbalanced order (a) 10% glucose solution, (b) 0.05% aspartame solution, (c) 9.0% maltodextrin solution, or (d) water as a control. Fifteen min after ingestion, repeated mouth rinsing was carried out with 11 × 15 ml bolus doses of the same solution at 30-s intervals. Each participant then performed a 45-s maximal sprint effort on a cycle ergometer. Peak power output was significantly higher in response to the glucose trial (1188 ± 166 W) compared with the water (1036 ± 177 W), aspartame (1088 ± 128 W) and maltodextrin (1024 ± 202 W) trials by 14.7 ± 10.6, 9.2 ± 4.6 and 16.0 ± 6.0% respectively (p sprint was significantly higher in the glucose trial compared with maltodextrin (p sprinting did not differ significantly between treatments (p > .05). These findings suggest that combining the ingestion of glucose with glucose mouth rinsing improves maximal sprint performance. This ergogenic effect is unlikely to be related to changes in blood glucose, sweetness, or energy sensing mechanisms in the gastrointestinal tract.

  6. Voxel model in BNCT treatment planning: performance analysis and improvements

    Science.gov (United States)

    González, Sara J.; Carando, Daniel G.; Santa Cruz, Gustavo A.; Zamenhof, Robert G.

    2005-02-01

    In recent years, many efforts have been made to study the performance of treatment planning systems in deriving an accurate dosimetry of the complex radiation fields involved in boron neutron capture therapy (BNCT). The computational model of the patient's anatomy is one of the main factors involved in this subject. This work presents a detailed analysis of the performance of the 1 cm based voxel reconstruction approach. First, a new and improved material assignment algorithm implemented in NCTPlan treatment planning system for BNCT is described. Based on previous works, the performances of the 1 cm based voxel methods used in the MacNCTPlan and NCTPlan treatment planning systems are compared by standard simulation tests. In addition, the NCTPlan voxel model is benchmarked against in-phantom physical dosimetry of the RA-6 reactor of Argentina. This investigation shows the 1 cm resolution to be accurate enough for all reported tests, even in the extreme cases such as a parallelepiped phantom irradiated through one of its sharp edges. This accuracy can be degraded at very shallow depths in which, to improve the estimates, the anatomy images need to be positioned in a suitable way. Rules for this positioning are presented. The skin is considered one of the organs at risk in all BNCT treatments and, in the particular case of cutaneous melanoma of extremities, limits the delivered dose to the patient. Therefore, the performance of the voxel technique is deeply analysed in these shallow regions. A theoretical analysis is carried out to assess the distortion caused by homogenization and material percentage rounding processes. Then, a new strategy for the treatment of surface voxels is proposed and tested using two different irradiation problems. For a parallelepiped phantom perpendicularly irradiated with a 5 keV neutron source, the large thermal neutron fluence deviation present at shallow depths (from 54% at 0 mm depth to 5% at 4 mm depth) is reduced to 2% on average

  7. Development of an improved performance SiGe unicouple

    Science.gov (United States)

    Nakahara, Jan F.; Franklin, Brian; DeFillipo, Lawrence E.

    1995-01-01

    This paper describes the fabrication of unicouples with improved SiGe alloys. Based on laboratory measurements of the thermoelectric properties the improved materials provide about a 10% improvement in the figure-of-merit between 573 and 1273 K compared to standard coarse grain unicouple materials. The improved materials are p-type Si0.796Ge0.199B0.005 fabricated at Martin Marietta Astro Space by the Vacuum casting/hot pressing method and n-type Si0.784Ge0.196Ga0.005P0.015 fabricated at Ames Laboratory by the mechanical alloying/hot isostatic pressing method. The standard unicouple bonding process was adjusted to accommodate the lower melting temperature of the SiGe/GaP material. A two-step diffusion bonding process was developed such that the p-type material is bonded to the SiMo hot shoe first at 1594 K followed by the lower melting point n-type material between 1518 and 1520 K. Standard procedures were used to silicon nitride coat the thermoelectric pellets and to attach the cold side CTE transition and heat rejection components to produce unicouples. Two unicouples successfully withstood simulated rivet operations as would be experienced in the fabrication of a Radioisotope Thermoelectric Generator (RTG) converter to verify the integrity of the tungsten cold shoe to thermoelectric material interface. The performance of these unicouples will be further evaluated in an 18-couple test module.

  8. Significant improvements in long trace profiler measurement performance

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, P.Z. [Brookhaven National Lab., Upton, NY (United States); Bresloff, C.J. [Argonne National Lab., IL (United States)

    1996-07-01

    A Modifications made to the Long Trace Profiler (LTP II) system at the Advanced Photon Source at Argonne National Laboratory have significantly improved the accuracy and repeatability of the instrument The use of a Dove prism in the reference beam path corrects for phasing problems between mechanical efforts and thermally-induced system errors. A single reference correction now completely removes both error signals from the measured surface profile. The addition of a precision air conditioner keeps the temperature in the metrology enclosure constant to within {+-}0.1{degrees}C over a 24 hour period and has significantly improved the stability and repeatability of the system. We illustrate the performance improvements with several sets of measurements. The improved environmental control has reduced thermal drift error to about 0.75 microradian RMS over a 7.5 hour time period. Measurements made in the forward scan direction and the reverse scan direction differ by only about 0.5 microradian RMS over a 500mm, trace length. We are now able to put 1-sigma error bar of 0.3 microradian on an average of 10 slope profile measurements over a 500mm long trace length, and we are now able to put a 0.2 microradian error bar on an average of 10 measurements over a 200mm trace length. The corresponding 1-sigma height error bar for this measurement is 1.1 run.

  9. A conceptual model to improve performance in virtual teams

    Directory of Open Access Journals (Sweden)

    Shopee Dube

    2016-04-01

    Full Text Available Background: The vast improvement in communication technologies and sophisticated project management tools, methods and techniques has allowed geographically and culturally diverse groups to operate and function in a virtual environment. To succeed in this virtual environment where time and space are becoming increasingly irrelevant, organisations must define new ways of implementing initiatives. This virtual environment phenomenon has brought about the formation of virtual project teams that allow organisations to harness the skills and knowhow of the best resources, irrespective of their location.Objectives: The aim of this article was to investigate performance criteria and develop a conceptual model which can be applied to enhance the success of virtual project teams. There are no clear guidelines of the performance criteria in managing virtual project teams.Method: A qualitative research methodology was used in this article. The purpose of content analysis was to explore the literature to understand the concept of performance in virtual project teams and to summarise the findings of the literature reviewed.Results: The research identified a set of performance criteria for the virtual project teams as follows: leadership, trust, communication, team cooperation, reliability, motivation, comfort and social interaction. These were used to conceptualise the model.Conclusion: The conceptual model can be used in a holistic way to determine the overall performance of the virtual project team, but each factor can be analysed individually to determine the impact on the overall performance. The knowledge of performance criteria for virtual project teams could aid project managers in enhancing the success of these teams and taking a different approach to better manage and coordinate them.

  10. Improve Performance of Data Warehouse by Query Cache

    Science.gov (United States)

    Gour, Vishal; Sarangdevot, S. S.; Sharma, Anand; Choudhary, Vinod

    2010-11-01

    The primary goal of data warehouse is to free the information locked up in the operational database so that decision makers and business analyst can make queries, analysis and planning regardless of the data changes in operational database. As the number of queries is large, therefore, in certain cases there is reasonable probability that same query submitted by the one or multiple users at different times. Each time when query is executed, all the data of warehouse is analyzed to generate the result of that query. In this paper we will study how using query cache improves performance of Data Warehouse and try to find the common problems faced. These kinds of problems are faced by Data Warehouse administrators which are minimizes response time and improves the efficiency of query in data warehouse overall, particularly when data warehouse is updated at regular interval.

  11. Improving productivity and firm performance with enterprise resource planning

    Science.gov (United States)

    Beheshti, Hooshang M.; Beheshti, Cyrus M.

    2010-11-01

    Productivity is generally considered to be the efficient utilisation of organisational resources and is measured in terms of the efficiency of a worker, company or nation. Focusing on efficiency alone, however, can be harmful to the organisation's long-term success and competitiveness. The full benefits of productivity improvement measures are realised when productivity is examined from two perspectives: operational efficiency (output/input) of an individual worker or a business unit as well as performance (effectiveness) with regard to end user or customer satisfaction. Over the years, corporations have adopted new technology to integrate business activities in order to achieve both effectiveness and efficiency in their operations. In recent years, many firms have invested in enterprise resource planning (ERP) in order to integrate all business activities into a uniform system. The implementation of ERP enables the firm to reduce the transaction costs of the business and improve its productivity, customer satisfaction and profitability.

  12. Improving AODV Performance using Dynamic Density Driven Route Request Forwarding

    CERN Document Server

    Kanakaris, Venetis; Ovaliadis, Kyriakos

    2011-01-01

    Ad-hoc routing protocols use a number of algorithms for route discovery. Some use flooding in which a route request packet (RREQ) is broadcasted from a source node to other nodes in the network. This often leads to unnecessary retransmissions, causing congestion and packet collisions in the network, a phenomenon called a broadcast storm. This paper presents a RREQ message forwarding scheme for AODV that reduces routing overheads. This has been called AODV_EXT. Its performance is compared to that of AODV, DSDV, DSR and OLSR protocols. Simulation results show that AODV_EXT achieves 3% energy efficiency, 19.5% improvement in data throughput and 69.5% reduction in the number of dropped packets for a network of 50 nodes. Greater efficiency is achieved in high density network and marginal improvement in networks with a small number of nodes.

  13. Improving the precision of genotype selection in wheat performance trials

    Directory of Open Access Journals (Sweden)

    Giovani Benin

    2013-12-01

    Full Text Available The aim of this study was to verify whether using the Papadakis method improves model assumptions and experimental accuracy in field trials used to determine grain yield for wheat lineages indifferent Value for Cultivation and Use (VCU regions. Grain yield data from 572 field trials at 31 locations in the VCU Regions 1, 2, 3 and 4 in 2007-2011 were used. Each trial was run with and without the use of the Papadakis method. The Papadakis method improved the indices of experimental precision measures and reduced the number of experimental repetitions required to predict grain yield performance among the wheat genotypes. There were differences among the wheat adaptation regions in terms of the efficiency of the Papadakis method, the adjustment coefficient of the genotype averages and the increases in the selective accuracy of grain yield.

  14. Attention competition with advertisement.

    Science.gov (United States)

    Cetin, Uzay; Bingol, Haluk O

    2014-09-01

    In the new digital age, information is available in large quantities. Since information consumes primarily the attention of its recipients, the scarcity of attention is becoming the main limiting factor. In this study, we investigate the impact of advertisement pressure on a cultural market where consumers have a limited attention capacity. A model of competition for attention is developed and investigated analytically and by simulation. Advertisement is found to be much more effective when the attention capacity of agents is extremely scarce. We have observed that the market share of the advertised item improves if dummy items are introduced to the market while the strength of the advertisement is kept constant.

  15. Attention competition with advertisement

    Science.gov (United States)

    Cetin, Uzay; Bingol, Haluk O.

    2014-09-01

    In the new digital age, information is available in large quantities. Since information consumes primarily the attention of its recipients, the scarcity of attention is becoming the main limiting factor. In this study, we investigate the impact of advertisement pressure on a cultural market where consumers have a limited attention capacity. A model of competition for attention is developed and investigated analytically and by simulation. Advertisement is found to be much more effective when the attention capacity of agents is extremely scarce. We have observed that the market share of the advertised item improves if dummy items are introduced to the market while the strength of the advertisement is kept constant.

  16. Early cessation of breastfeeding amongst women in South Africa: an area needing urgent attention to improve child health

    Directory of Open Access Journals (Sweden)

    Doherty Tanya

    2012-07-01

    Full Text Available Abstract Background Breastfeeding is a critical component of interventions to reduce child mortality. Exclusive breastfeeding practice is extremely low in South Africa and there has been no improvement in this over the past ten years largely due to fears of HIV transmission. Early cessation of breastfeeding has been found to have negative effects on child morbidity and survival in several studies in Africa. This paper reports on determinants of early breastfeeding cessation among women in South Africa. Methods This is a sub group analysis of a community-based cluster-randomized trial (PROMISE EBF promoting exclusive breastfeeding in three South African sites (Paarl in the Western Cape Province, and Umlazi and Rietvlei in KwaZulu-Natal between 2006 and 2008 (ClinicalTrials.gov no: NCT00397150. Infant feeding recall of 22 food and fluid items was collected at 3, 6, 12 and 24 weeks postpartum. Women’s experiences of breast health problems were also collected at the same time points. 999 women who ever breastfed were included in the analysis. Univariable and multivariable logistic regression analysis adjusting for site, arm and cluster, was performed to determine predictors of stopping breastfeeding by 12 weeks postpartum. Results By 12 weeks postpartum, 20% of HIV-negative women and 40% of HIV-positive women had stopped all breastfeeding. About a third of women introduced other fluids, most commonly formula milk, within the first 3 days after birth. Antenatal intention not to breastfeed and being undecided about how to feed were most strongly associated with stopping breastfeeding by 12 weeks (Adjusted odds ratio, AOR 5.6, 95% CI 3.4 – 9.5 and AOR 4.1, 95% CI 1.6 – 10.8, respectively. Also important was self-reported breast health problems associated with a 3-fold risk of stopping breastfeeding (AOR 3.1, 95%CI 1.7 – 5.7 and the mother having her own income doubled the risk of stopping breastfeeding (AOR 1.9, 95% CI 1.3 – 2

  17. Improving retention and performance in civil society in Uganda.

    Science.gov (United States)

    O'Neil, Mary L; Paydos, Michael

    2008-06-20

    This article is the second article in the Human Resources for Health journal's first quarterly feature. The series of seven articles has been contributed by Management Sciences for Health (MSH) under the theme of leadership and management in public health and will be published article-by-article over the next few weeks. The journal invited Dr Manuel M. Dayrit, Director of the WHO Department of Human Resources for Health and former Minister of Health for the Philippines to launch the feature with an opening editorial to be found in the journal's blog. This article--number two in the series--describes the experience of the Family Life Education Programme (FLEP), a reproductive health program that provides community-based health services through 40 clinics in five districts of Uganda, in improving retention and performance by using the Management Sciences for Health (MSH) Human Resource Management Rapid Assessment Tool. A few years ago, the FLEP of Busoga Diocese began to see an increase in staff turnover and a decrease in overall organizational performance. The workplace climate was poor and people stopped coming for services even though there were few other choices in the area. An external assessment found the quality of the health care services provided was deficient. An action plan to improve their human resource management (HRM) system was developed and implemented. To assess the strengths and weaknesses of their system and to develop an action plan, they used the Rapid Assessment Tool. The tool guides users through a process of prioritizing and action planning after the assessment is done. By implementing the various recommended changes, FLEP established an improved, responsive HRM system. Increased employee satisfaction led to less staff turnover, better performance, and increased utilization of health services. These benefits were achieved by cost-effective measures focused on professionalizing the organization's approach to HRM.

  18. Improving retention and performance in civil society in Uganda

    Directory of Open Access Journals (Sweden)

    Paydos Michael

    2008-06-01

    Full Text Available Abstract This article is the second article in the Human Resources for Health journal's first quarterly feature. The series of seven articles has been contributed by Management Sciences for Health (MSH under the theme of leadership and management in public health and will be published article-by-article over the next few weeks. The journal invited Dr Manuel M. Dayrit, Director of the WHO Department of Human Resources for Health and former Minister of Health for the Philippines to launch the feature with an opening editorial to be found in the journal's blog. This article – number two in the series – describes the experience of the Family Life Education Programme (FLEP, a reproductive health program that provides community-based health services through 40 clinics in five districts of Uganda, in improving retention and performance by using the Management Sciences for Health (MSH Human Resource Management Rapid Assessment Tool. A few years ago, the FLEP of Busoga Diocese began to see an increase in staff turnover and a decrease in overall organizational performance. The workplace climate was poor and people stopped coming for services even though there were few other choices in the area. An external assessment found the quality of the health care services provided was deficient. An action plan to improve their human resource management (HRM system was developed and implemented. To assess the strengths and weaknesses of their system and to develop an action plan, they used the Rapid Assessment Tool. The tool guides users through a process of prioritizing and action planning after the assessment is done. By implementing the various recommended changes, FLEP established an improved, responsive HRM system. Increased employee satisfaction led to less staff turnover, better performance, and increased utilization of health services. These benefits were achieved by cost-effective measures focused on professionalizing the organization's approach to HRM.

  19. An Effective Concept Extraction Method for Improving Text Classification Performance

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yuntao; GONG Ling; WANG Yongcheng; YIN Zhonghang

    2003-01-01

    This paper presents anew way to extract concept that can beused to improve text classification per-formance (precision and recall). Thecomputational measure will be dividedinto two layers. The bottom layercalled document layer is concernedwith extracting the concepts of parti-cular document and the upper layercalled category layer is with findingthe description and subject concepts ofparticular category. The relevant im-plementation algorithm that dramatic-ally decreases the search space is dis-cussed in detail. The experiment basedon real-world data collected from Info-Bank shows that the approach is supe-rior to the traditional ones.

  20. Improvement for the steering performance of liquid crystal phased array

    Institute of Scientific and Technical Information of China (English)

    SONG Yan; KONG Ling-jiang; CHEN Jun; ZHU Ying; YANG Jian-yu

    2009-01-01

    Optical phased array technology is introduced and the steering performances of liquid crystal phased array are discussed, several factors affecting the beam steering performances arc analyzed completely, also simple models for some typical factors are developed. Then, a new method based on iterating and modifying the output phase pattern of liquid crystal phase shifters is proposed. Using this method, the modified voltages applied on electrodes of liquid crystal phase shifters can be obtained, after applying the voltages, the influence of factors can be compensated to some extent; the steering angle accu-racy and efficiency with liquid crystal phased array can be improved. Through the simulation for the angle range from 0° to -1°, the error of steering angle can be reduced three orders of magnitude, and the efficiency can be increased almost 30% after several iterations.

  1. Performance Improvement of a Measurement Station for Superconducting Cable Test

    CERN Document Server

    Arpaia, P; Montenero, G; Le Naour, S

    2012-01-01

    A fully digital system, improving measurements flexibility, integrator drift, and current control of superconducting transformers for cable test, is proposed. The system is based on a high-performance integration of Rogowski coil signal and a flexible direct control of the current into the secondary windings. This allows state-of-the-art performance to be overcome by means of out-of-the-shelf components: on a full-scale of 32 kA, current measurement resolution of 1 A, stability below 0.25 Amin-1, and controller ripple less than 50 ppm. The system effectiveness has been demonstrated experimentally on the superconducting transformer of the Facility for the Research of Superconducting Cables at the European Organization for Nuclear Research (CERN).

  2. Performance improvement of software component with partial evaluation

    Institute of Scientific and Technical Information of China (English)

    MAO Hong-yan; HUANG Lin-peng; LI Ming-lu

    2008-01-01

    To avoid the complexity and inefficiency for specific applications of the current software architecture, a novel approach using partial evaluation is proposed to improve the running performance of components. The generic program was specialized into domain-specific realization for the known knowledge and environments. The syntax and semantic(adj.) were analyzed based on byte code instruction sequences, and partial evaluation rules depicted how to perform the specialization. The partial evaluation for object-oriented programs was imple-mented. The experimental results show that partial evaluation is effective to speed up the running efficiency. The more generality and scalability can be obtained by the integration of partial evaluation with the favorable de-sign mechanisms and compiler optimization technology.

  3. Performance Improvement of TCP by TCP Reno and SACK Acknowledgement

    Directory of Open Access Journals (Sweden)

    Mrs. Reena Rai

    2012-03-01

    Full Text Available Transmission Control Protocol (TCP is the dominating end-to-end transport layer protocol which provides secure and reliable data transfer together with some other protocols. In this review paper, we contend that existing approaches to improve TCP performance over mobile ad-hoc networks have focused only on a subset of the factors affecting TCP performance by TCP Reno, SACK and Vegas. Effective resource utilization, such as bandwidth utilization, retransmission rate and window size, is compared. for evaluate these TCP congestion control algorithms from many aspects are present and We also concern fair resource allocation from two main categories, one is fairness between different delay links, and the other is competition between different TCP congestion control algorithms

  4. Butterfly micro bilayer thermal energy harvester geometry with improved performances

    Science.gov (United States)

    Trioux, E.; Monfray, S.; Basrour, S.

    2016-11-01

    This paper reports the recent progress of a new technology to scavenge thermal energy, implying a double-step transduction through thermal buckling of a bilayer aluminum nitride / aluminum bridge and piezoelectric transduction. A completely new scavenger design is presented, improving greatly its final performance. The butterfly shape reduces the overall device mechanical rigidity, which leads to a decrease of buckling temperatures compared to previously studied rectangular plates. In a first time we compared performances of rectangular and butterfly plates with an equal thickness of Al and AlN. In a second time, with a thicker Al layer than AlN layer, we will study only butterfly structure in terms of output power and buckling temperatures, and compare it to the previous stack.

  5. Prioritising Investments in Marketing Activities to Improve Business Performance

    DEFF Research Database (Denmark)

    Martensen, Anne; Mouritsen, Jan

    2014-01-01

    dimensions: (1) Small m: marketing strategy and marketing implementation and (2) big M: cross-functional coordination and innovation. Big M and small m interact and influence BP similarly. When considering investing in marketing activities to improve financial performance, the first priority is to recruit...... and retain competent employees and the second, to collect, disseminate and act upon market insight in the form of measurement of effectiveness and production of intelligence. These provide resources for the development of a customer-oriented marketing strategy that in turn helps innovation and cross......The purpose of this study is to prioritise investments in marketing activities based on their effect on business performance (BP). On the basis of the European Foundation for Quality Management (EFQM) model adapted to a marketing context, four generic marketing activities are structured in two...

  6. On improving linear solver performance: a block variant of GMRES

    Energy Technology Data Exchange (ETDEWEB)

    Baker, A H; Dennis, J M; Jessup, E R

    2004-05-10

    The increasing gap between processor performance and memory access time warrants the re-examination of data movement in iterative linear solver algorithms. For this reason, we explore and establish the feasibility of modifying a standard iterative linear solver algorithm in a manner that reduces the movement of data through memory. In particular, we present an alternative to the restarted GMRES algorithm for solving a single right-hand side linear system Ax = b based on solving the block linear system AX = B. Algorithm performance, i.e. time to solution, is improved by using the matrix A in operations on groups of vectors. Experimental results demonstrate the importance of implementation choices on data movement as well as the effectiveness of the new method on a variety of problems from different application areas.

  7. Performance Improvement of Cache Management In Cluster Based MANET

    Directory of Open Access Journals (Sweden)

    Abdulaziz Zam

    2013-08-01

    Full Text Available Caching is one of the most effective techniques used to improve the data access performance in wireless networks. Accessing data from a remote server imposes high latency and power consumption through forwarding nodes that guide the requests to the server and send data back to the clients. In addition, accessing data may be unreliable or even impossible due to erroneous wireless links and frequently disconnections. Due to the nature of MANET and its high frequent topology changes, and also small cache size and constrained power supply in mobile nodes, the management of the cache would be a challenge. To maintain the MANET’s stability and scalability, clustering is considered as an effective approach. In this paper an efficient cache management method is proposed for the Cluster Based Mobile Ad-hoc NETwork (C-B-MANET. The performance of the method is evaluated in terms of packet delivery ratio, latency and overhead metrics.

  8. Location decision strategies for improving SMME business performance

    Directory of Open Access Journals (Sweden)

    Shereen Barnard

    2011-12-01

    relationship between electricity tariffs and business performance. Employment and business performance attained the strongest positive relationship; indicating that business owners regarded employment as an important factor to consider when searching for suitable business premises. The relationship between location and business performance obtained the lowest positive correlation. Originality and value of the research: Research on South African SMMEs regarding location decisions and the specific factors identified in this study has not been done previously in South Africa. Therefore, because evidence exists that the macro-environmental factors influence location decisions to varying degrees, this study can provide SMME owners with insight into the factors influencing location choice. It is vital that business owners consider these factors as they could influence business performance, and ultimately, business survival. An increased awareness of the importance of the aspects discussed in this study could consequently lead to improved performance in the SMME sector.

  9. Device Engineering Towards Improved Tin Sulfide Solar Cell Performance and Performance Reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Steinmann, Vera; Chakraborty, Rupak; Rekemeyer, Paul; Siol, Sebastian; Martinot, Loic; Polizzotti, Alex; Yang, Chuanxi; Hartman, Katy; Gradecak, Silvija; Zakutayev, Andriy; Gordon, Roy G.; Buonassisi, Tonio

    2016-11-21

    As novel absorber materials are developed and screened for their photovoltaic (PV) properties, the challenge remains to rapidly test promising candidates in high-performing PV devices. There is a need to engineer new compatible device architectures, including the development of novel transparent conductive oxides and buffer layers. Here, we consider the two approaches of a substrate-style and a superstrate-style device architecture for novel thin-film solar cells. We use tin sulfide as a test absorber material. Upon device engineering, we demonstrate new approaches to improve device performance and performance reproducibility.

  10. Play for Performance: Using Computer Games to Improve Motivation and Test-Taking Performance

    Science.gov (United States)

    Dennis, Alan R.; Bhagwatwar, Akshay; Minas, Randall K.

    2013-01-01

    The importance of testing, especially certification and high-stakes testing, has increased substantially over the past decade. Building on the "serious gaming" literature and the psychology "priming" literature, we developed a computer game designed to improve test-taking performance using psychological priming. The game primed…

  11. Improvements and Performance of the Fermilab Solenoid Test

    Energy Technology Data Exchange (ETDEWEB)

    Orris, Darryl; et al.

    2016-09-02

    The Solenoid Test Facility at Fermilab was built using a large vacuum vessel for testing of conduction-cooled superconducting solenoid magnets, and was first used to determine the performance of the MICE Coupling Coil [1, 2]. The facility was modified recently to enable testing of solenoid magnets for the Mu2e experiment, which operate at much higher current than the Coupling Coil. One pair of low current conduction-cooled copper and NbTi leads was replaced with two pairs of 10 kA HTS leads cooled by heat exchange with liquid nitrogen and liquid helium. The new design, with additional control and monitoring capability, also provides helium cooling of the superconducting magnet leads by conduction. A high current power supply with energy extraction was added, and several improvements to the quench protection and characterization system were made. Here we present details of these changes and report on performance results from a test of the Mu2e prototype Transport Solenoid (TS) module. Progress on additional improvements in preparation for production TS module testing will be presented.

  12. Power optimization and performance improvement for embedded Ethernet SOC

    Institute of Scientific and Technical Information of China (English)

    ZHENG Zhao-xia; ZOU Lian-ying; GAO Jun

    2008-01-01

    Information appliance is the combination of traditional home appliances and the internet technology. In this article, an Ethernet controller system-on-chip (SOC) solution for information appliances is presented. To achieve high performance, the embedded 8 bits 8051 micro control unit (MCU) is optimized by an independent instruction bus and a data bus. Besides, a two-stage pipeline feature is added. Compared with the existing 8051 core, the enhanced one-cycle MCU offers ten times improvement in instruction execution efficiency. Mean- while, the performance of media access control (MAC) circuit is greatly improved by adopting various techniques such as direct memory access (DMA) control, paging strategy, etc. To reduce the power consumption, clock gating, low power supply, and multi-working-clock are adopted. Moreover, to achieve rapid data communication in different clock frequency circuits, a simple ping-pong first in first out (FIFO) circuit is realized. The chip is implemented using TSMC 0.25 μm two-poly four-metal mixed signal complementary metal oxide semiconductor (CMOS) technology. Its die area is mm. The test results show that the maximum throughput of Ethernet packets can reach 7 Mb/s while the power consumption is rather low-the working current is just about 200 mA.

  13. Distributed Large Dataset Deployment with Improved Load Balancing and Performance

    Directory of Open Access Journals (Sweden)

    Siddharth Bhandari

    2016-08-01

    Full Text Available Cloud computing is a prototype for permitting universal, appropriate, on-demand network access. Cloud is a method of computing where enormously scalable IT-enabled proficiencies are delivered „as a service‟ using Internet tools to multiple outdoor clients. Virtualization is the establishment of a virtual form of something such as computing device or server, an operating system, or network devices and storage device. The different names for cloud data management are DaaS Data as a service, Cloud Storage, and DBaaS Database as a service. Cloud storage permits users to store data, information in documents formats. iCloud, Google drive, Drop box, etc. are most common and widespread cloud storage methods. The main challenges connected with cloud database are fault tolerance, scalability, data consistency, high availability and integrity, confidentiality and many more. Load balancing improves the performance of the data center. We propose an architecture which provides load balancing to the cloud database. We introduced a load balancing server which calculates the load of the data center using our proposed algorithm and distributes the data accordingly to the different data centers. Experimental results showed that it also improve the performance of the cloud system

  14. Combined Space and Water Heating: Next Steps to Improved Performance

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Bohac, D. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States); Huelman, P. [NorthernSTAR Building America Partnership, Minneapolis, MN (United States)

    2016-07-13

    A combined space- and water-heating (combi) system uses a high-efficiency direct-vent burner that eliminates safety issues associated with natural draft appliances. Past research with these systems shows that using condensing water heaters or boilers with hydronic air handling units can provide both space and water heating with efficiencies of 90% or higher. Improved controls have the potential to reduce complexity and improve upon the measured performance. This project demonstrates that controls can significantly benefit these first-generation systems. Laboratory tests and daily load/performance models showed that the set point temperature reset control produced a 2.1%–4.3% (20–40 therms/year) savings for storage and hybrid water heater combi systems operated in moderate-load homes. The full modulation control showed additional savings over set point control (in high-load homes almost doubling the savings: 4%–5% over the no-control case). At the time of installation the reset control can be implemented for $200–$400, which would provide paybacks of 6–25 years for low-load houses and 3–15 years for high-load houses. Full modulation implementation costs would be similar to the outdoor reset and would provide paybacks of 5-½–20 years for low-load houses and 2-½–10 years for high-load houses.

  15. Plasma Aerodynamic Control Effectors for Improved Wind Turbine Performance

    Energy Technology Data Exchange (ETDEWEB)

    Mehul P. Patel; Srikanth Vasudevan; Robert C. Nelson; Thomas C. Corke

    2008-08-01

    Orbital Research Inc is developing an innovative Plasma Aerodynamic Control Effectors (PACE) technology for improved performance of wind turbines. The PACE system is aimed towards the design of "smart" rotor blades to enhance energy capture and reduce aerodynamic loading and noise using flow-control. The PACE system will provide ability to change aerodynamic loads and pitch distribution across the wind turbine blade without any moving surfaces. Additional benefits of the PACE system include reduced blade structure weight and complexity that should translate into a substantially reduced initial cost. During the Phase I program, the ORI-UND Team demonstrated (proof-of-concept) performance improvements on select rotor blade designs using PACE concepts. Control of both 2-D and 3-D flows were demonstrated. An analytical study was conducted to estimate control requirements for the PACE system to maintain control during wind gusts. Finally, independent laboratory experiments were conducted to identify promising dielectric materials for the plasma actuator, and to examine environmental effects (water and dust) on the plasma actuator operation. The proposed PACE system will be capable of capturing additional energy, and reducing aerodynamic loading and noise on wind turbines. Supplementary benefits from the PACE system include reduced blade structure weight and complexity that translates into reduced initial capital costs.

  16. Improving Emergency Response and Human-Robotic Performance

    Energy Technology Data Exchange (ETDEWEB)

    David I. Gertman; David J. Bruemmer; R. Scott Hartley

    2007-08-01

    Preparedness for chemical, biological, and radiological/nuclear incidents at nuclear power plants (NPPs) includes the deployment of well trained emergency response teams. While teams are expected to do well, data from other domains suggests that the timeliness and accuracy associated with incident response can be improved through collaborative human-robotic interaction. Many incident response scenarios call for multiple, complex procedure-based activities performed by personnel wearing cumbersome personal protective equipment (PPE) and operating under high levels of stress and workload. While robotic assistance is postulated to reduce workload and exposure, limitations associated with communications and the robot’s ability to act independently have served to limit reliability and reduce our potential to exploit human –robotic interaction and efficacy of response. Recent work at the Idaho National Laboratory (INL) on expanding robot capability has the potential to improve human-system response during disaster management and recovery. Specifically, increasing the range of higher level robot behaviors such as autonomous navigation and mapping, evolving new abstractions for sensor and control data, and developing metaphors for operator control have the potential to improve state-of-the-art in incident response. This paper discusses these issues and reports on experiments underway intelligence residing on the robot to enhance emergency response.

  17. Plans for performance and model improvements in the LISE++ software

    Science.gov (United States)

    Kuchera, M. P.; Tarasov, O. B.; Bazin, D.; Sherrill, B. M.; Tarasova, K. V.

    2016-06-01

    The LISE++ software for fragment separator simulations is undergoing a major update. LISE++ is the standard software used at in-flight separator facilities for predicting beam intensity and purity. The code simulates nuclear physics experiments where fragments are produced and then selected with a fragment separator. A set of modifications to improve the functionality of the code is discussed in this work. These modifications include transportation to a modern graphics framework and updated compilers to aid in the performance and sustainability of the code. To accommodate the diversity of our users' computer platform preferences, we extend the software from Windows to a cross-platform application. The calculations of beam transport and isotope production are becoming more computationally intense with the new large scale facilities. Planned new features include new types of optimization, for example, optimization of ion optics, improvements in reaction models, and new event generator options. In addition, LISE++ interface with control systems are planned. Computational improvements as well as the schedule for updating this large package will be discussed.

  18. Neck-cooling improves repeated sprint performance in the heat

    Directory of Open Access Journals (Sweden)

    Caroline eSunderland

    2015-11-01

    Full Text Available The present study evaluated the effect of neck-cooling during exercise on repeated sprint ability in a hot environment. Seven team-sport playing males completed two experimental trials involving repeated sprint exercise (5 x 6 s before and after two 45 min bouts of a football specific intermittent treadmill protocol in the heat (33.0  0.2 ºC; 53 ± 2% relative humidity. Participants wore a neck-cooling collar in one of the trials (CC. Mean power output and peak power output declined over time in both trials but were higher in CC (540 ± 99 v 507 ± 122W, d = 0.32; 719 ± 158 v 680 ± 182 W, d = 0.24 respectively. The improved power output was particularly pronounced (d = 0.51 – 0.88 after the 2nd 45 min bout but the CC had no effect on % fatigue. The collar lowered neck temperature and the thermal sensation of the neck (P 0.05. There were no trial differences but interaction effects were demonstrated for prolactin concentration and rating of perceived exertion (RPE. Prolactin concentration was initially higher in the collar cold trial and then was lower from 45 minutes onwards (interaction trial x time P=0.04. RPE was lower during the football intermittent treadmill protocol in the collar cold trial (interaction trial x time P = 0.01. Neck-cooling during exercise improves repeated sprint performance in a hot environment without altering physiological or neuroendocrinological responses. RPE is reduced and may partially explain the performance improvement.

  19. Improving human object recognition performance using video enhancement techniques

    Science.gov (United States)

    Whitman, Lucy S.; Lewis, Colin; Oakley, John P.

    2004-12-01

    Atmospheric scattering causes significant degradation in the quality of video images, particularly when imaging over long distances. The principle problem is the reduction in contrast due to scattered light. It is known that when the scattering particles are not too large compared with the imaging wavelength (i.e. Mie scattering) then high spatial resolution information may be contained within a low-contrast image. Unfortunately this information is not easily perceived by a human observer, particularly when using a standard video monitor. A secondary problem is the difficulty of achieving a sharp focus since automatic focus techniques tend to fail in such conditions. Recently several commercial colour video processing systems have become available. These systems use various techniques to improve image quality in low contrast conditions whilst retaining colour content. These systems produce improvements in subjective image quality in some situations, particularly in conditions of haze and light fog. There is also some evidence that video enhancement leads to improved ATR performance when used as a pre-processing stage. Psychological literature indicates that low contrast levels generally lead to a reduction in the performance of human observers in carrying out simple visual tasks. The aim of this paper is to present the results of an empirical study on object recognition in adverse viewing conditions. The chosen visual task was vehicle number plate recognition at long ranges (500 m and beyond). Two different commercial video enhancement systems are evaluated using the same protocol. The results show an increase in effective range with some differences between the different enhancement systems.

  20. A Meta-Analytic Study of Event Rate Effects on Go/No-Go Performance in Attention-Deficit/Hyperactivity Disorder

    NARCIS (Netherlands)

    Metin, Baris; Roeyers, Herbert; Wiersema, Jan R.; van der Meere, Jaap; Sonuga-Barke, Edmund

    2012-01-01

    Background: According to the state regulation deficit model, event rate( ER) is an important determinant of performance of children with attention-deficit/hyperactivity disorder (ADHD). Fast ER is predicted to create over activation and produce errors of commission, whereas slow ER is thought to cre

  1. The JT8D and JT9D engine component improvement: Performance improvement program

    Science.gov (United States)

    Gaffin, W. O.

    1982-01-01

    The NASA sponsored Engine Component Improvement - Performance Improvement Program at Pratt & Whitney Aircraft advanced the state of the art of thermal barrier coatings and ceramic seal systems, demonstrated the practicality of an advanced turbine clearance control system and an advanced fan design in the JT9D engine, and demonstrated the advantages of modern cooling, sealing, and aerodynamic designs in the high pressure turbine and compressor of the JT8D engine. Several of these improvements are already in airline service in JT8D and JT9D engines, and others will enter service soon in advanced models of these engines. In addition, the technology advances are being transferred to completely new engine configurations, the PW2037 engine and the NASA sponsored Energy Efficient Engine.

  2. Learning faces: similar comparator faces do not improve performance.

    Directory of Open Access Journals (Sweden)

    Scott P Jones

    Full Text Available Recent evidence indicates that comparison of two similar faces can aid subsequent discrimination between them. However, the fact that discrimination between two faces is facilitated by comparing them directly does not demonstrate that comparison produces a general improvement in the processing of faces. It remains an open question whether the opportunity to compare a "target" face to similar faces can facilitate the discrimination of the exposed target face from other nonexposed faces. In Experiment 1, selection of a target face from an array of novel foils was not facilitated by intermixed exposure to the target and comparators of the same sex. Experiment 2 also found no advantage for similar comparators (morphed towards the target over unmorphed same sex comparators, or over repeated target exposure alone. But all repeated exposure conditions produced better performance than a single brief presentation of the target. Experiment 3 again demonstrated that repeated exposure produced equivalent learning in same sex and different sex comparator conditions, and also showed that increasing the number of same sex or different sex comparators failed to improve identification. In all three experiments, exposure to a target alongside similar comparators failed to support selection of the target from novel test stimuli to a greater degree than exposure alongside dissimilar comparators or repeated target exposure alone. The current results suggest that the facilitatory effects of comparison during exposure may be limited to improving discrimination between exposed stimuli, and thus our results do not support the idea that providing the opportunity for comparison is a practical means for improving face identification.

  3. Innovative approaches to improve bulk heterojunction organic photovoltaic device performance

    Science.gov (United States)

    Zhang, Ye

    In this thesis we studied the electrical properties of bulk heterojunction organic photovoltaic (OPV) devices fabricated using a variety of conjugated polymers, including regioregular P3HT, regiorandom P3HT, MEH-PPV and Mercedes, and several fullerene derivatives including [C61]PCBM, [C71]PCBM, bis-PCBM, Jalapeno and Habanero. We first optimized the fabrication recipe for P3HT/PCBM devices to yield a power conversion efficiency ˜3.5%, which is comparable to the reported state-of-the-art P3HT/PCBM device performance. We then fabricated OPV devices using alternative high LUMO fullerenes and a narrow bandgap/deep HOMO polymer to enhance OPV device performance and studied the electrical properties of these devices. Devices fabricated using P3HT/Jalapeno demonstrate a high efficiency ˜5%. Finally, we discovered an innovative spin-related method, which can potentially compliment the use of alternative donor/acceptor materials, to enhance OPV device performance. We doped the spin ½ radial Galvinoxyl into P3HT/PCBM devices and improved efficiency from 3.5% to 4%. Our experimental results suggest that the existence of Galvinoxyl at the P3HT/PCBM interface facilitates the exciton/polaron dissociation process, while Galvinoxyl molecules that are sparsely distributed in PCBM domains yield enhanced free charge carrier transport.

  4. Improving friction performance of cast iron by laser shock peening

    Science.gov (United States)

    Feng, Xu; Zhou, Jianzhong; Huang, Shu; Sheng, Jie; Mei, Yufen; Zhou, Hongda

    2015-05-01

    According to different purpose, some high or low friction coefficient of the material surface is required. In this study, micro-dent texture was fabricated on cast iron specimens by a set of laser shock peening (LSP) experiments under different laser energy, with different patterns of micro dimples in terms of the depth over diameter. The mechanism of LSP was discussed and surface morphology of the micro dimples were investigated by utilizing a Keyence KS-1100 3D optical surface profilometer. The tests under the conditions of dry and lubricating sliding friction were accomplished on the UMT-2 apparatus. The performance of treated samples during friction and wear tests were characterized and analyzed. Based on theoretical analysis and experimental study, friction performance of textured and untextured samples were studied and compared. Morphological characteristics were observed by scanning electron microscope (SEM) and compared after friction tests under dry condition. The results showed that friction coefficient of textured samples were obvious changed than smooth samples. It can be seen that LSP is an effective way to improve the friction performance of cast iron by fabricating high quality micro dimples on its surface, no matter what kind of engineering application mentioned in this paper.

  5. Chicken Essence Improves Exercise Performance and Ameliorates Physical Fatigue

    Directory of Open Access Journals (Sweden)

    Wen-Ching Huang

    2014-07-01

    Full Text Available Chicken essence (CE is a liquid nutritional supplement made from cooking whole chickens. In traditional Chinese medicine, CE is used to support health, promote healing, increase metabolism, and relieve fatigue. However, few studies have examined the effect of CE on exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effects of CE on fatigue and ergogenic functions following physical challenge in mice. Male ICR mice were divided into four groups to receive vehicle or CE by oral gavage at 0, 845, 1690, or 4225 mg/kg/day for 4 weeks. Exercise performance and anti-fatigue function were evaluated by forelimb grip strength, exhaustive swimming time, and levels of physical fatigue-related biomarkers serum lactate, ammonia, glucose, and creatine kinase (CK after physical challenge. CE supplementation dose-dependently elevated endurance and grip strength. CE supplementation significantly decreased lactate, ammonia, and CK levels after physical challenge. Tissue glycogen content, an important energy source for exercise, was significantly increased with CE supplementation. In addition, CE supplementation had few subchronic toxic effects. The supplementation with CE can have a wide spectrum of bioactivities on health promotion, performance improvement and anti-fatigue.

  6. A Multimodal Approach to Improve the Performance of Biometric System

    Directory of Open Access Journals (Sweden)

    Chander Kant

    2015-08-01

    Full Text Available Biometric systems have very success rate in identifying an individual based on ones biological traits. In biometric history some features like weight, age, height etc. are also there to provide user recognition to some extent but not fully upto the mark because of their changing nature according to time and environment. These features are called soft biometric traits. Soft biometric traits are lack of permanence but they have some positive aspects in respect of enhancing the biometric system performance. Here in this paper, we have also highlighting the similar point but with a new aspect that is integrating the soft biometrics with fingerprint and face for improving the performance of biometric system. Here we have proposed an architecture of three different sensors to evaluate the system performance. The approach includes soft biometrics, fingerprint and face features, we have also proven the efficiency of proposed system regarding FAR (False Acceptance Ratio and total response time, with the help of MUBI tool (Multimodal Biometrics Integration.

  7. Leveraging Structure to Improve Classification Performance in Sparsely Labeled Networks

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, B; Eliassi-Rad, T

    2007-10-22

    We address the problem of classification in a partially labeled network (a.k.a. within-network classification), with an emphasis on tasks in which we have very few labeled instances to start with. Recent work has demonstrated the utility of collective classification (i.e., simultaneous inferences over class labels of related instances) in this general problem setting. However, the performance of collective classification algorithms can be adversely affected by the sparseness of labels in real-world networks. We show that on several real-world data sets, collective classification appears to offer little advantage in general and hurts performance in the worst cases. In this paper, we explore a complimentary approach to within-network classification that takes advantage of network structure. Our approach is motivated by the observation that real-world networks often provide a great deal more structural information than attribute information (e.g., class labels). Through experiments on supervised and semi-supervised classifiers of network data, we demonstrate that a small number of structural features can lead to consistent and sometimes dramatic improvements in classification performance. We also examine the relative utility of individual structural features and show that, in many cases, it is a combination of both local and global network structure that is most informative.

  8. IMPROVING CONSISTENCY OF PERFORMANCE ASSESSMENTS IN THE DOE COMPLEX

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, R; Elmer Wilhite, E

    2009-01-20

    The low-level waste (LLW) performance assessment (PA) process has been traditionally focused on disposal facilities at a few United States Department of Energy (USDOE) sites and commercial disposal facilities. In recent years, there has been a dramatic increase in the scope of the use of PA-like modeling approaches, involving multiple activities, facilities, contractors and regulators. The scope now includes, for example: (1) National Environmental Policy Act (NEPA) assessments, (2) CERCLA disposal cells, (3) Waste Determinations and High-Level Waste (HLW) Closure activities, (4) Potential on-site disposal of Transuranic (TRU) waste, and (5) In-situ decommissioning (including potential use of existing facilities for disposal). The dramatic increase in the variety of activities requiring more detailed modeling has resulted in a similar increase in the potential for inconsistency in approaches both at a site and complexwide scale. This paper includes a summary of USDOE Environmental Management (EM) sponsored initiatives and activities for improved consistency. New initiatives entitled the Performance Assessment Community of Practice and Performance Assessment Assistance Team are also introduced.

  9. The effects of attentional focus on jump performance and knee joint kinematics in patients after ACL reconstruction

    NARCIS (Netherlands)

    Gokeler, Alli; Benjaminse, Anne; Welling, Wouter; Alferink, Malou; Eppinga, Peter; Otten, Bert

    2015-01-01

    Objectives: The purpose of this study was to determine the effect of an internal and external attentional focus on single leg hop jump distance and knee kinematics in patients after ACL reconstruction (ACLR). Design: Experimental. Setting: Outpatient physical therapy facility. Participants: Sixteen

  10. The effects of attentional focus on jump performance and knee joint kinematics in patients after ACL reconstruction

    NARCIS (Netherlands)

    Gokeler, Alli; Benjaminse, Anne; Welling, Wouter; Alferink, Malou; Eppinga, Peter; Otten, Bert

    2015-01-01

    OBJECTIVES: The purpose of this study was to determine the effect of an internal and external attentional focus on single leg hop jump distance and knee kinematics in patients after ACL reconstruction (ACLR). DESIGN: Experimental. SETTING: Outpatient physical therapy facility. PARTICIPANTS: Sixteen

  11. Neuropsychological Test Performance and the Attention Deficit Disorders: Clinical Utility of the Luria-Nebraska Neuropsychological Battery-Children's Revision.

    Science.gov (United States)

    Schaughency, Elizabeth A.; And Others

    1989-01-01

    Administered Luria-Nebraska Neuropsychological Battery--Children's Revision (LNNB-CR) to 54 clinic-referred children aged 8-12 years. Compared children reliably diagnosed as attention deficit disorder (ADD) with hyperactivity, without hyperactivity, and control group with internalizing disorders. Findings failed to support hypothesis that ADD is…

  12. SPICE: Sentinel-3 Performance Improvement for Ice Sheets

    Science.gov (United States)

    Benveniste, Jérôme; Escolà, Roger; Roca, Mònica; Ambrózio, Américo; Restano, Marco; McMillan, Malcolm; Escorihuela, Maria Jose; Shepherd, Andrew; Thibaut, Pierre; Remy, Frederique

    2016-07-01

    Since the launch of ERS-1 in 1991, polar-orbiting satellite radar altimeters have provided a near continuous record of ice sheet elevation change, yielding estimates of ice sheet mass imbalance at the scale of individual ice sheet basins. One of the principle challenges associated with radar altimetry comes from the relatively large ground footprint of conventional pulse-limited radars, which limits their capacity to make reliable measurements in areas of complex topographic terrain. In recent years, progress has been made towards improving ground resolution, through the implementation of Synthetic Aperture Radar (SAR), or Delay-Doppler, techniques. In 2010, the launch of CryoSat-2 by the European Space Agency heralded the start of a new era of SAR altimetry, although full SAR coverage of the polar ice sheets will only be achieved with the launch of the first Sentinel-3 satellite in February 2016. Because of the heritage of SAR altimetry provided by CryoSat-2, current SAR altimeter processing techniques have been optimized and evaluated for water and sea ice surfaces. This leaves several outstanding issues related to the development and evaluation of SAR altimetry for ice sheets, including improvements to SAR processing algorithms and SAR altimetry waveform retracking procedures. Here we will present interim results from SPICE (Sentinel-3 Performance Improvement for Ice Sheets), a 2 year project that focuses on the expected performance of Sentinel-3 SAR altimetry over the Polar ice sheets. The project, which began in September 2015 and is funded by ESA's SEOM (Scientific Exploitation of Operational Missions) programme, aims to contribute to the development and understanding of ice sheet SAR altimetry through the emulation of Sentinel-3 data from dedicated CryoSat SAR acquisitions made at several sites in Antarctica and Greenland. More specifically, the project aims to (1) evaluate and improve the current Delay-Doppler processing and SAR waveform retracking

  13. Microstructured Electrolyte Membranes to Improve Fuel Cell Performance

    Science.gov (United States)

    Wei, Xue

    Fuel cells, with the advantages of high efficiency, low greenhouse gas emission, and long lifetime are a promising technology for both portable power and stationary power sources. The development of efficient electrolyte membranes with high ionic conductivity, good mechanical durability and dense structure at low cost remains a challenge to the commercialization of fuel cells. This thesis focuses on exploring novel composite polymer membranes and ceramic electrolytes with the microstructure engineered to improve performance in direct methanol fuel cells (DMFCs) and solid oxide fuel cells (SOFCs), respectively. Polymer/particle composite membranes hold promise to meet the demands of DMFCs at lower cost. The structure of composite membranes was controlled by aligning proton conducting particles across the membrane thickness under an applied electric field. The field-induced structural changes caused the membranes to display an enhanced water uptake, proton conductivity, and methanol permeability in comparison to membranes prepared without an applied field. Although both methanol permeability and proton conductivity are enhanced by the applied field, the permeability increase is relatively lower than the proton conductivity improvement, which results in enhanced proton/methanol selectivity and improved DMFC performance. Apatite ceramics are a new class of fast ion conductors being studied as alternative SOFC electrolytes in the intermediate temperature range. An electrochemical/hydrothermal deposition method was developed to grow fully dense apatite membranes containing well-developed crystals with c-axis alignment to promote ion conductivity. Hydroxyapatite seed crystals were first deposited onto a metal substrate electrochemically. Subsequent ion substitution during the hydrothermal growth process promoted the formation of dense, fully crystalline films with microstructure optimal for ion transport. The deposition parameters were systematically investigated, such as

  14. Can textured insoles improve ankle proprioception and performance in dancers?

    Science.gov (United States)

    Steinberg, Nili; Waddington, Gordon; Adams, Roger; Karin, Janet; Begg, Rezaul; Tirosh, Oren

    2016-08-01

    With the aim of determining both the acute and the chronic effects of textured insoles on the ankle discrimination and performance ability of dancers, 60 ballet dancers from the Australian Ballet School, aged 14-19 years, were divided into three groups (two intervention groups and a control group), age- and level-matched. In the first 5 weeks (weeks 1 to 5), the first intervention group (GRP1) was asked to wear textured insoles in their ballet shoes and the second intervention group (GRP2) was not given textured insoles to wear. In the next 5 weeks (weeks 6 to 10), GRP2 was asked to wear the same type of textured insoles and GRP1 did not wear the textured insoles. The control group (CTRL) did not wear textured insoles during the whole 10 weeks. All participants were tested preintervention, after 5 weeks and after 10 weeks for ankle discrimination score (AUC scores). Dance performance was assessed by 5-7 dance teachers. Pre-to-post change in AUC scores was significantly greater for the groups wearing insoles than for the controls (P = .046) and the size of pre-to-post changes did not differ between the two intervention groups (P = .834). Significant correlation was found between ankle discrimination score and performance scores, using the textured insoles (r = .412; P = .024). In conclusion, the stimulation to the proprioceptive system arising from textured insoles worn for five weeks was sufficient to improve the proprioceptive ability and performance ability of ballet dancers.

  15. Recovery Act: Electrochromic Glazing Technology: Improved Performance, Lower Price

    Energy Technology Data Exchange (ETDEWEB)

    Burdis, Mark; Sbar, Neil

    2012-06-30

    The growing dependency of the US on energy imports and anticipated further increases in energy prices reinforce the concerns about meeting the energy demand in the future and one element of a secure energy future is conservation. It is estimated that the buildings sector represents 40% of the US's total energy consumption. And buildings produce as much as one third of the greenhouse gas emissions primarily through fossil fuel usage during their operational phase. A significant fraction of this energy usage is simply due to inefficient window technology. Electrochromic (EC) windows allow electronic control of their optical properties so that the transparency to light can be adjusted from clear to dark. This ability to control the amount of solar energy allowed into the building can be advantageously used to minimize lighting, heating and air conditioning costs. Currently, the penetration of EC windows into the marketplace is extremely small, and consequently there is a huge opportunity for energy savings if this market can be expanded. In order to increase the potential energy savings it is necessary to increase the quantity of EC windows in operation. Additionally, any incremental improvement in the energy performance of each window will add to the potential energy savings. The overall goals of this project were therefore to improve the energy performance and lower the cost of dynamic (EC) smart windows for residential and commercial building applications. This project is obviously of benefit to the public by addressing two major areas: lowering the cost and improving the energy performance of EC glazings. The high level goals for these activities were: (i) to improve the range between the clear and the tinted state, (ii) reduce the price of EC windows by utilizing lower cost materials, (iii) lowering the U-Value1 SAGE Electrochromics Inc. is the only company in the US which has a track record of producing EC windows, and presently has a small operational

  16. Improved Fatigue Performance of Threaded Drillstring Connections by Cold Rolling

    Energy Technology Data Exchange (ETDEWEB)

    Kristoffersen, Steinar

    2002-01-01

    pits inside the pipe. Therefore, an optimisation of the roll geometry and rolling parameters was not possible. However, a significant fatigue life improvement was achieved. Based on experiments, a roller with similar profile as the thread root is recommended. A rolling force of maximum 20 kN is recommended to minimise the possibility of damaging the thread profile. Shallow cracks were observed typically when 5% of the fatigue life had expired. Re-rolling after 50% of expected improved fatigue life, when also short cracks were observed in the notch roots further increased the fatigue improvement. Pretensioned small steel specimens with a notch were used to simulate cold rolled threads. The specimens were fatigue tested in tension with minimum load close to zero. Pretensioning increased the fatigue life from approximately 50 000 cycles to an infinite number of cycles. In these tests non-propagating cracks of typically 0.4 mm length were found. The benefit from pretensioning gradually disappeared with increasing mean stress. FE analyses indicated that an almost instant relaxation of residual stresses to a level with no monotonic strain hardening from preloading would take place when cycled at moderate mean stress. Cycled at low mean stress, an instant relaxation of the surface layer was found in analysis. All observations from notched pretensioned fatigue specimens were in good agreement with the available literature. However, preloading was found to be strain rate dependent in tests where a pretension load held for 2 minutes gave a longer fatigue life than a sinusoidal loading-unloading cycle performed over a one minute interval. Strain hardening was found not contributing to the fatigue life improvement, whereas the polishing effect from improved surface quality after cold rolling increased the fatigue initiation period. However, residual stress and subsequent early crack closure was the dominating effect at moderate cyclic mean loads. The material data required to

  17. Improved cycling performance with ingestion of hydrolyzed marine protein depends on performance level

    Directory of Open Access Journals (Sweden)

    Vegge Geir

    2012-04-01

    , ingestion of NpPROCHO resulted in improved 5-min mean-power performance relative to ingestion of CHO in the six lesser performing subjects compared to the six superior performing subjects (P

  18. Beneficial microstructured titania photoanodes for improving DSSC performance

    Science.gov (United States)

    Ahmed, Saquib

    Critical assessment of economically viable renewable energy sources is essential for the development of a globally sustainable society. Dye sensitized solar cells (DSSCs) offer a viable alternative to traditional silicon and thin film photovoltaic (PV) technologies owing to their potential low cost and facile manufacturing. The two main challenges in enhancing device cell performance lie in improving the open circuit voltage (VOC), and suppressing recombination in the semiconductor TiO2 matrix. This thesis explores the latter challenge through investigation of a novel microstructured TiO2 photoanode system. In this research, we have synthesized CTAB-templated mesoporous, anatase, high surface area TiO2 using an acidic precursor to enhance dye adsorption. Through simple supramolecular self-assembly of the TiO2 particles during the synthesis, we have discovered a self-assembled system of TiO2 nanocrystallite aggregates with high surface area, which when applied as the photoanode in DSSCs, result in a novel high-roughness film beneficial for dye adsorption, and also lead to enhanced intrinsic light-scattering within the film itself. The TiO2 nanocrystallites are highly crystalline, with good interconnectivity for improved electron conduction. An additional unique and beneficial feature inherent of this novel photoanode film is its hierarchical meso- and macro-porosity, leading to improved electrolyte percolation through the TiO2 matrix---thereby providing better access to dye molecules for regeneration to occur more effectively (enhanced charge transfer). In all, we have fabricated a TiO2 system through a one-step process that incorporates key beneficial microstructural features crucial for enhancing DSSC behavior. We have further carried out critical TiCl4 surface treatment studies of this porous electrode structure of TiO2 aggregates to understand and improve upon recombination kinetics in the photonanode film matrix, together with enhancing its intrinsic light

  19. An Effective Analysis of Weblog Files to Improve Website Performance

    Directory of Open Access Journals (Sweden)

    T.Revathi

    2012-02-01

    Full Text Available As there is an enormous growth in the web in terms of web sites, the size of web usage data is also increasing gradually. But this web usage data plays a vital role in the effective management of web sites. This web usage data is stored in a file called weblog by the web server. In order to discover the knowledge, required for improving the performance of websites, we need to apply the best preprocessing methodology on the server weblog file. Data preprocessing is a phase which automatically identifies the meaningful patterns and user behavior. So far analyzing the weblog data has been a challenging task in the area of web usage mining. In this paper we propose an effective and enhanced data preprocessing methodology which produces an efficient usage patterns and reduces the size of weblog down to 75-80% of its initial size. The experimental results are also shown in the following chapters.

  20. Performance improvement of complementary feeders using static transfer switch system

    Institute of Scientific and Technical Information of China (English)

    Tahir MAHMOOD; Mohammad Ahmad CHOUDHRY

    2009-01-01

    The performance of complementary feeders, running in parallel, can be significantly improved by installing static transfer switches (STSs) at critical locations. We develop the STS control logic, which transfers the critical load from the preferred feeder to the alternate feeder when a voltage sag or a fault occurs on the preferred feeder. A forced commutation technique is proposed and implemented to turn off the preferred feeders' thyristor, thus avoiding cross current to flow and minimizing the transfer time. Simulation results show that the forced commutation technique is more effective as compared to the recently pro-posed time delay technique for STS operation. Two different feeders, namely New Exchange, the preferred feeder, and Sector I-10/2, the alternate feeder of Islamabad Electric Supply COmpany (IESCO), Pakistan, have been selected for case studies. The software PSCAD/EMTDC professional package has been used for simulation.

  1. An integrated turbocharger design approach to improve engine performance

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Turbocharging technology is today considered as a promising way for internal combustion engine energy saving and CO2 reduction.Turbocharger design is a major challenge for turbocharged engine performance improvement.The turbocharger designer must draw upon the information of engine operation conditions,and an appropriate link between the engine requirements and design features must be carefully developed to generate the most suitable design recommendation.The objective of this research is to develop a turbocharger design approach for better turbocharger matching to an internal combustion engine.The development of the approach is based on the concept of turbocharger design and interaction links between engine cycle requirements and design parameter values.A turbocharger through flow model is then used to generate the design alternatives.This integrated method has been applied with success to a gasoline engine turbocharger assembly.

  2. Improving public health system performance through multiorganizational partnerships.

    Science.gov (United States)

    Mays, Glen P; Scutchfield, F Douglas

    2010-11-01

    Public health activities in the United States are delivered through multiple public and private organizations that vary widely in their resources, missions, and operations. Without strong coordination mechanisms, these delivery arrangements may perpetuate large gaps, inequities, and inefficiencies in public health activities. We examined evidence and uncertainties concerning the use of partnerships to improve the performance of the public health system, with a special focus on partnerships between public health agencies and health care organizations. We found that the types of partnerships likely to have the largest and most direct effects on population health are among the most difficult, and therefore least prevalent, forms of collaboration. High opportunity costs and weak and diffuse participation incentives hinder partnerships that focus on expanding effective prevention programs and policies. Targeted policy actions and leadership strategies are required to illuminate and enhance partnership incentives.

  3. ARES v2 - new features and improved performance

    CERN Document Server

    Sousa, S G; Adibekyan, V; Delgado-Mena, E; Israelian, G

    2015-01-01

    Aims: We present a new upgraded version of ARES. The new version includes a series of interesting new features such as automatic radial velocity correction, a fully automatic continuum determination, and an estimation of the errors for the equivalent widths. Methods: The automatic correction of the radial velocity is achieved with a simple cross-correlation function, and the automatic continuum determination, as well as the estimation of the errors, relies on a new approach to evaluating the spectral noise at the continuum level. Results: ARES v2 is totally compatible with its predecessor. We show that the fully automatic continuum determination is consistent with the previous methods applied for this task. It also presents a significant improvement on its performance thanks to the implementation of a parallel computation using the OpenMP library.

  4. Control Performance Management in Industrial Automation Assessment, Diagnosis and Improvement of Control Loop Performance

    CERN Document Server

    Jelali, Mohieddine

    2013-01-01

    Control Performance Management in Industrial Automation provides a coherent and self-contained treatment of a group of methods and applications of burgeoning importance to the detection and solution of problems with control loops that are vital in maintaining product quality, operational safety, and efficiency of material and energy consumption in the process industries. The monograph deals with all aspects of control performance management (CPM), from controller assessment (minimum-variance-control-based and advanced methods), to detection and diagnosis of control loop problems (process non-linearities, oscillations, actuator faults), to the improvement of control performance (maintenance, re-design of loop components, automatic controller re-tuning). It provides a contribution towards the development and application of completely self-contained and automatic methodologies in the field. Moreover, within this work, many CPM tools have been developed that goes far beyond available CPM packages. Control Perform...

  5. Quantifying quality management system performance in order to improve business performance

    Directory of Open Access Journals (Sweden)

    Smith, Richard Angus

    2014-08-01

    Full Text Available This study investigates current methods of measuring quality management system (QMS performance. It introduces a methodology to quantify QMS performance in order to provide a reference point for improved QMS performance and, in turn, the business’s performance. By introducing metadata into historical or current QMS internal audit data, the study shows that it is possible, over time, to extract various levels of value-adding data, ranging from high-level, strategic, direction-oriented insight, to process effectiveness and implementation-level guidance. This is accomplished by a repeatable process of infusing cause and effect theming data and process-consequence severity data into the QMS audit- findings data, and subsequently analysing the additional metadata.

  6. Feedback and feedforward: Focal points for improving academic performance

    Directory of Open Access Journals (Sweden)

    María José García San Pedro

    2012-09-01

    Full Text Available The effective integration of competencies in university programmes follows a holistic and diversified assessment model and the educational potential development of students’ assessment results. This work questions: how are students informed about the results of their learning? Specifically, it aims to understand students’ and professors’ perspectives about the use of learning results and the strategies that are promoted in the practice of improved use of their educational potential. The results described are derived from a case study on 12 degree graduates adapted to the EEES. Although feedback and the feedfoward are strategies for informing students about their learning results, the results of the study show that their use is not entirely generalised and frequently only inform the grades obtained. Students identify the difference between knowing the grade and obtaining feedback. The relational dimension is also valued positively when students are informed about the results of their assessment. However, it seems that use of the educational potential is pending. The students say that the tutorials and the follow up through continual assessment helps to reduce failure. Also, the faculty identifies that reflection about the results obtained is very much linked to metacognitive reflection, although it is not generalised in practice. The students recognise the limitations and the work load involved for the professor to individually monitor them. The study is concluded with the need for systematically incorporating feedback and feedforward in teaching practices and offers guidelines for orienting these strategies towards improving academic performance.

  7. Kinetic models in industrial biotechnology - Improving cell factory performance.

    Science.gov (United States)

    Almquist, Joachim; Cvijovic, Marija; Hatzimanikatis, Vassily; Nielsen, Jens; Jirstrand, Mats

    2014-07-01

    An increasing number of industrial bioprocesses capitalize on living cells by using them as cell factories that convert sugars into chemicals. These processes range from the production of bulk chemicals in yeasts and bacteria to the synthesis of therapeutic proteins in mammalian cell lines. One of the tools in the continuous search for improved performance of such production systems is the development and application of mathematical models. To be of value for industrial biotechnology, mathematical models should be able to assist in the rational design of cell factory properties or in the production processes in which they are utilized. Kinetic models are particularly suitable towards this end because they are capable of representing the complex biochemistry of cells in a more complete way compared to most other types of models. They can, at least in principle, be used to in detail understand, predict, and evaluate the effects of adding, removing, or modifying molecular components of a cell factory and for supporting the design of the bioreactor or fermentation process. However, several challenges still remain before kinetic modeling will reach the degree of maturity required for routine application in industry. Here we review the current status of kinetic cell factory modeling. Emphasis is on modeling methodology concepts, including model network structure, kinetic rate expressions, parameter estimation, optimization methods, identifiability analysis, model reduction, and model validation, but several applications of kinetic models for the improvement of cell factories are also discussed.

  8. Improvement of physical performance by transcutaneous nerve stimulation in athletes.

    Science.gov (United States)

    Kaada, B

    1984-01-01

    The present pilot study tested the exercise response to transcutaneous nerve stimulation (TNS) of 21 volunteers, who were well-trained competitive athletes. In 62 experiments (n) they received low-frequency TNS (2 Hz) for 30-45 min prior to either a road or track race, swimming race, bicycle ergometer exercise, isometric muscular endurance test, or dynamometer hand grip test. Improvement in performance compared with a corresponding number of control tests, without TNS or with placebo stimulation in the same subjects, was almost regularly observed in running, swimming and ergometer cycling, although with great individual variations. The average improvement was 4.3 sec (2.2%) in 1.000 m road racing (n = 9); 2.3 sec (1.8%) in 800 m track racing (n = 5); 0.9 sec (1.4%) in 100 m swimming (n = 12); 1.3 sec (0.8%) in 200 m swimming (n = 6); and 2.5 sec (0.9%) in 400 m swimming (n = 3). In a bicycle ergometer test with stepwise, progressive exercise to muscular fatigue, the maximal capacity was increased by 9% (n = 4). Local isometric muscle endurance of the elbow flexors (n = 7) and hand grip strengths (n = 11) were not significantly altered. Possible mechanisms involved in the response to TNS are discussed.

  9. Improving Ballistic Performance of Polyurethane Foam by Nanoparticle Reinforcement

    Directory of Open Access Journals (Sweden)

    M. F. Uddin

    2009-01-01

    Full Text Available We report improving ballistic performance of polyurethane foam by reinforcing it with nanoscale TiO2 particles. Particles were dispersed through a sonic cavitation process and the loading of particles was 3 wt% of the total polymer. Once foams were reinforced, sandwich panels were made and impacted with fragment simulating projectiles (FSPs in a 1.5-inch gas gun. Projectile speed was set up to have complete penetration of the target in each experiment. Test results have indicated that sandwich with nanophased cores absorbed about 20% more kinetic energy than their neat counterpart. The corresponding increase in ballistic limit was around 12% over the neat control samples. The penetration phenomenon was also monitored using a high-speed camera. Analyses of digital images showed that FSP remained inside the nanophased sandwich for about 7 microseconds longer than that of a neat sandwich demonstrating improved energy absorption capability of the nanoparticle reinforced core. Failure modes for energy absorption have been investigated through a microscope and high-speed images.

  10. Optimization Controller for Mechatronic Sun Tracking System to Improve Performance

    Directory of Open Access Journals (Sweden)

    Mustafa Engin

    2013-01-01

    Full Text Available An embedded system that contains hardware and software was developed for two-axis solar tracking system to improve photovoltaic panel utilization. The hardware section of the embedded system consists of a 32-bit ARM core microcontroller, motor driver circuits, a motion control unit, pyranometer, GPS receiver, and an anemometer. The real-time control algorithm enables the solar tracker to operate automatically without external control as a stand-alone system, combining the advantages of the open-loop and the closed-loop control methods. The pyranometer is employed to continuously send radiation data to the controller if the measured radiation is above the lower radiation limit the photovoltaic panel can generate power, guaranteeing the solar tracking process to be highly efficient. The anemometer is utilized in the system to ensure that the solar tracking procedure halts under high wind speed conditions to protect the entire system. Latitude, longitude, altitude, date, and real-time clock data are provided by GPS receiver. The algorithm calculates solar time using astronomical equations with GPS data and converts it to pulse-width modulated motor control signal. The overall objective of this study is to develop a control algorithm that improves performance and reliability of the two-axis solar tracker, focusing on optimization of the controller board, drive hardware, and software.

  11. Design and Performance of an Improved Trapped Vortex Combustor

    Institute of Scientific and Technical Information of China (English)

    JIN Yi; HE Xiaomin; JIANG Bo; WU Zejun; DING Guoyu

    2012-01-01

    A trapped vortex combustor (TVC) has been a very promising novel concept for it offers improvements in lean blow out,altitude relight,operating range,as well as a potential to decrease NOx emissions compared to conventional combustors.The present paper discusses the improved designs of the new combustor over the prior ones of our research group,including that:a) the overall dimensions,both axial and radial,are reduced to those of an actual aero-engine combustor; b) the air flow distribution is optimized,and especially 15% of the air is fed into the liner as cooling air; c) a straight-wall diffuser with divergence angle 9° is added.A series of experiments (cavity-fueled only,under atmospheric pressure) has been conducted to investigate the performance of the improved TVC.Experimental results show that at the inlet temperature of 523 K,the inlet pressure of 0.1 MPa,stable operation of the TVC test rig is observed for the Mach number 0.15-0.34,indicating good flame stability; the combustion efficiency obtained in this paper falls into the range of 60%-96%; as the total excess air ratio increases,the combustion efficiency decreases,while the increase of the inlet temperature is beneficial to high combustion efficiency; besides,the optimal Mach numbers for high combustion efficiency under different inlet conditions are confirmed.The outlet temperature profiles feature a bottom in the mid-height of the exit.This paper demonstrates the feasibility for the TVC to be applied to a realistic aero-engine preliminarily and provides reference for TVC design.

  12. Non toxic additives for improved fabric filter performance

    Energy Technology Data Exchange (ETDEWEB)

    Bustard, C.J.; Baldrey, K.E.; Ebner, T.G. [ADA Technologies, Inc., Englewood, CO (United States)] [and others

    1995-11-01

    The overall objective of this three-phase Small Business innovative Research (SBIR) program funded by the Department of Energy pittsburgh Energy Technology Center (PETC) is to commercialize a technology based upon the use of non-toxic, novel flue gas conditioning agents to improve particulate air toxic control and overall fabric filter performance. The ultimate objective of the Phase II program currently in progress is to demonstrate that the candidate additives are successful at full-scale on flue gas from a coal-fired utility boiler. This paper covers bench-scale field tests conducted during the period February through May, 1995. The bench-scale additives testing was conducted on a flue gas slipstream taken upstream of the existing particulate control device at a utility power plant firing a Texas lignite coal. These tests were preceded by extensive testing with additives in the laboratory using a simulated flue gas stream and re-dispersed flyash from the same power plant. The bench-scale field testing was undertaken to demonstrate the performance with actual flue gas of the bet candidate additives previously identified in the laboratory. Results from the bench-scale tests will be used to establish operating parameters for a larger-scale demonstration on either a single baghouse compartment or a full baghouse at the same site.

  13. Improving JWST Coronagraphic Performance with Accurate Image Registration

    Science.gov (United States)

    Van Gorkom, Kyle; Pueyo, Laurent; Lajoie, Charles-Philippe; JWST Coronagraphs Working Group

    2016-06-01

    The coronagraphs on the James Webb Space Telescope (JWST) will enable high-contrast observations of faint objects at small separations from bright hosts, such as circumstellar disks, exoplanets, and quasar disks. Despite attenuation by the coronagraphic mask, bright speckles in the host’s point spread function (PSF) remain, effectively washing out the signal from the faint companion. Suppression of these bright speckles is typically accomplished by repeating the observation with a star that lacks a faint companion, creating a reference PSF that can be subtracted from the science image to reveal any faint objects. Before this reference PSF can be subtracted, however, the science and reference images must be aligned precisely, typically to 1/20 of a pixel. Here, we present several such algorithms for performing image registration on JWST coronagraphic images. Using both simulated and pre-flight test data (taken in cryovacuum), we assess (1) the accuracy of each algorithm at recovering misaligned scenes and (2) the impact of image registration on achievable contrast. Proper image registration, combined with post-processing techniques such as KLIP or LOCI, will greatly improve the performance of the JWST coronagraphs.

  14. Electrolysis Performance Improvement Concept Study (EPICS) Flight Experiment-Reflight

    Science.gov (United States)

    Schubert, F. H.

    1997-01-01

    The Electrolysis Performance Improvement Concept Study (EPICS) is a flight experiment to demonstrate and validate in a microgravity environment the Static Feed Electrolyzer (SFE) concept which was selected for the use aboard the International Space Station (ISS) for oxygen (O2) generation. It also is to investigate the impact of microgravity on electrochemical cell performance. Electrochemical cells are important to the space program because they provide an efficient means of generating O2 and hydrogen (H2) in space. Oxygen and H2 are essential not only for the survival of humans in space but also for the efficient and economical operation of various space systems. Electrochemical cells can reduce the mass, volume and logistical penalties associated with resupply and storage by generating and/or consuming these gases in space. An initial flight of the EPICS was conducted aboard STS-69 from September 7 to 8, 1995. A temperature sensor characteristics shift and a missing line of software code resulted in only partial success of this initial flight. Based on the review and recommendations of a National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) review team a reflight activity was initiated to obtain the remaining desired results, not achieved during the initial flight.

  15. COOLING FAN AND SYSTEM PERFORMANCE AND EFFICIENCY IMPROVEMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Dupree

    2005-07-31

    Upcoming emissions regulations (Tiers 3, 4a and 4b) are imposing significantly higher heat loads on the cooling system than lesser regulated machines. This work was a suite of tasks aimed at reducing the parasitic losses of the cooling system, or improving the design process through six distinct tasks: 1. Develop an axial fan that will provide more airflow, with less input power and less noise. The initial plan was to use Genetic Algorithms to do an automated fan design, incorporating forward sweep for low noise. First and second generation concepts could not meet either performance or sound goals. An experienced turbomachinery designer, using a specialized CFD analysis program has taken over the design and has been able to demonstrate a 5% flow improvement (vs 10% goal) and 10% efficiency improvement (vs 10% goal) using blade twist only. 2. Fan shroud developments, using an 'aeroshroud' concept developed at Michigan State University. Performance testing at Michigan State University showed the design is capable of meeting the goal of a 10% increase in flow, but over a very narrow operating range of fan performance. The goal of 10% increase in fan efficiency was not met. Fan noise was reduced from 0 to 2dB, vs. a goal of 5dB at constant airflow. The narrow range of fan operating conditions affected by the aeroshroud makes this concept unattractive for further development at this time 3. Improved axial fan system modeling is needed to accommodate the numbers of cooling systems to be redesigned to meet lower emissions requirements. A CFD fan system modeling guide has been completed and transferred to design engineers. Current, uncontrolled modeling practices produce flow estimates in some cases within 5% of measured values, and in some cases within 25% of measured values. The techniques in the modeling guide reduced variability to the goal of + 5% for the case under study. 4. Demonstrate the performance and design versatility of a high performance fan. A

  16. Suppression of emission rates improves sonar performance by flying bats.

    Science.gov (United States)

    Adams, Amanda M; Davis, Kaylee; Smotherman, Michael

    2017-01-31

    Echolocating bats face the challenge of actively sensing their environment through their own emissions, while also hearing calls and echoes of nearby conspecifics. How bats mitigate interference is a long-standing question that has both ecological and technological implications, as biosonar systems continue to outperform man-made sonar systems in noisy, cluttered environments. We recently showed that perched bats decreased calling rates in groups, displaying a behavioral strategy resembling the back-off algorithms used in artificial communication networks to optimize information throughput at the group level. We tested whether free-tailed bats (Tadarida brasiliensis) would employ such a coordinated strategy while performing challenging flight maneuvers, and report here that bats navigating obstacles lowered emission rates when hearing artificial playback of another bat's calls. We measured the impact of acoustic interference on navigation performance and show that the calculated reductions in interference rates are sufficient to reduce interference and improve obstacle avoidance. When bats flew in pairs, each bat responded to the presence of the other as an obstacle by increasing emissions, but hearing the sonar emissions of the nearby bat partially suppressed this response. This behavior supports social cohesion by providing a key mechanism for minimizing mutual interference.

  17. [Comprehensive reform to improve health system performance in Mexico].

    Science.gov (United States)

    Frenk, Julio; González-Pier, Eduardo; Gómez-Dantés, Octavio; Lezana, Miguel Angel; Knaul, Felicia Marie

    2007-01-01

    Despite having achieved an average life expectancy of 75 years, much the same as that of more developed countries, Mexico entered the 21st century with a health system mared by its failure to offer financial protection in health to more than half of its citizens; this was both a result and a cause of the social inequalities that have marked the development process in Mexico. Several structural limitations have hampered performance and limited the progress of the health system. Conscious that the lack of financial protection was the major bottleneck, Mexico has embarked on a structural reform to improve health system performance by establishing the System of Social Protection in Health (SSPH), which has introduced new financial rules and incentives. The main innovation of the reform has been the Seguro Popular (Popular Health Insurance), the insurance-based component of the SSPH, aimed at funding health care for all those families, most of them poor, who had been previously excluded from social health insurance. The reform has allowed for a substantial increase in public investment in health while realigning incentives towards better technical and interpersonal quality. This paper describes the main features and initial results of the Mexican reform effort, and derives lessons for other countries considering health-system transformations under similarly challenging circumstances.

  18. Comprehensive reform to improve health system performance in Mexico.

    Science.gov (United States)

    Frenk, Julio; González-Pier, Eduardo; Gómez-Dantés, Octavio; Lezana, Miguel A; Knaul, Felicia Marie

    2006-10-28

    Despite having achieved an average life expectancy of 75 years, much the same as that of more developed countries, Mexico entered the 21st century with a health system marred by its failure to offer financial protection in health to more than half of its citizens; this was both a result and a cause of the social inequalities that have marked the development process in Mexico. Several structural limitations have hampered performance and limited the progress of the health system. Conscious that the lack of financial protection was the major bottleneck, Mexico has embarked on a structural reform to improve health system performance by establishing the System of Social Protection in Health (SSPH), which has introduced new financial rules and incentives. The main innovation of the reform has been the Seguro Popular (Popular Health Insurance), the insurance-based component of the SSPH, aimed at funding health care for all those families, most of them poor, who had been previously excluded from social health insurance. The reform has allowed for a substantial increase in public investment in health while realigning incentives towards better technical and interpersonal quality. This paper describes the main features and initial results of the Mexican reform effort, and derives lessons for other countries considering health-system transformations under similarly challenging circumstances.

  19. Improving Application Launch Performance on Solid State Drives

    Institute of Scientific and Technical Information of China (English)

    Yongsoo Joo; Junhee Ryu; Sangsoo Park; Kang G.Shin

    2012-01-01

    Application launch performance is of great importance to system platform developers and vendors as it greatly affects the degree of users' satisfaction.The single most effective way to improve application launch performance is to replace a hard disk drive (HDD) with a solid state drive (SSD),which has recently become affordable and popular.A natural question is then whether or not to replace the traditional HDD-aware application launchers with a new SSD-aware optimizer.We address this question by analyzing the inefficiency of the HDD-aware application launchers on SSDs and then proposing a new SSD-aware application prefetching scheme,called the Fast Application STarter (FAST).The key idea of FAST is to overlap the computation (CPU) time with the SSD access (I/O) time during an application launch.FAST is composed of a set of user-level components and system debugging tools provided by Linux OS (operating system).Hence,FAST can be easily deployed in any recent Linux versions without kernel recompilation.We implement FAST on a desktop PC with an SSD running Linux 2.6.32 OS and evaluate it by launching a set of widely-used applications,demonstrating an average of 28% reduction of application launch time as compared to PC without a prefetcher.

  20. PERFORMANCE IMPROVEMENT IN CLOUD COMPUTING USING RESOURCE CLUSTERING

    Directory of Open Access Journals (Sweden)

    G. Malathy

    2013-01-01

    Full Text Available Cloud computing is a computing paradigm in which the various tasks are assigned to a combination of connections, software and services that can be accessed over the network. The computing resources and services can be efficiently delivered and utilized, making the vision of computing utility realizable. In various applications, execution of services with more number of tasks has to perform with minimum intertask communication. The applications are more likely to exhibit different patterns and levels and the distributed resources organize into various topologies for information and query dissemination. In a distributed system the resource discovery is a significant process for finding appropriate nodes. The earlier resource discovery mechanism in cloud system relies on the recent observations. In this study, resource usage distribution for a group of nodes with identical resource usages patterns are identified and kept as a cluster and is named as resource clustering approach. The resource clustering approach is modeled using CloudSim, a toolkit for modeling and simulating cloud computing environments and the evaluation improves the performance of the system in the usage of the resources. Results show that resource clusters are able to provide high accuracy for resource discovery.