WorldWideScience

Sample records for survey feedback process

  1. Systematic errors in the measurement of neutrino masses due to baryonic feedback processes: Prospects for stage IV lensing surveys

    CERN Document Server

    Natarajan, Aravind; Battaglia, Nicholas; Trac, Hy

    2014-01-01

    We examine the importance of baryonic feedback effects on the matter power spectrum on small scales, and the implications for the precise measurement of neutrino masses through gravitational weak lensing. Planned large galaxy surveys such as the Large Synoptic Sky Telescope (LSST) and Euclid are expected to measure the sum of neutrino masses to extremely high precision, sufficient to detect non-zero neutrino masses even in the minimal mass normal hierarchy. We show that weak lensing of galaxies while being a very good probe of neutrino masses, is extremely sensitive to baryonic feedback processes. We use publicly available results from the Overwhelmingly Large Simulations (OWLS) project to investigate the effects of active galactic nuclei feedback, the nature of the stellar initial mass function, and gas cooling rates, on the measured weak lensing shear power spectrum. Using the Fisher matrix formalism and priors from CMB+BAO data, we show that when one does not account for feedback, the measured neutrino mas...

  2. Social feedback processing in borderline personality disorder.

    Science.gov (United States)

    Korn, C W; La Rosée, L; Heekeren, H R; Roepke, S

    2016-02-01

    Patients with borderline personality disorder (BPD) show negative and unstable self- and other-evaluations compared to healthy individuals. It is unclear, however, how they process self- and other-relevant social feedback. We have previously demonstrated a positive updating bias in healthy individuals: When receiving social feedback on character traits, healthy individuals integrate desirable more than undesirable feedback. Here, our aim was to test whether BPD patients exhibit a more negative pattern of social feedback processing. We employed a character trait task in which BPD patients interacted with four healthy participants in a real-life social interaction. Afterwards, all participants rated themselves and one other participant on 80 character traits before and after receiving feedback from their interaction partners. We compared how participants updated their ratings after receiving desirable and undesirable feedback. Our analyses included 22 BPD patients and 81 healthy controls. Healthy controls showed a positivity bias for self- and other-relevant feedback as previously demonstrated. Importantly, this pattern was altered in BPD patients: They integrated undesirable feedback for themselves to a greater degree than healthy controls did. Other-relevant feedback processing was unaltered in BPD patients. Our study demonstrates an alteration in self-relevant feedback processing in BPD patients that might contribute to unstable and negative self-evaluations.

  3. Content Analysis of Survey Feedback Meetings: An Evaluation Tool

    Science.gov (United States)

    1975-05-01

    AD-AO10 210 CONTENT ANALYSIS OF SURVEY FEEDBACK MEETINGS: AN EVALUATION TOOL Patricia A. Pecorella Michigan University Prepared for: Office of Naval...RECIPIENIT’S CATALOG NUMSEA 4, TITLE (#wtd$4bIII*) 5.&TYJ F REPORT 6PEFlIOg COVERlEO Content Analysis of Survey Feedback Meetings: Technical Report An...Ratings Coder Re1liability Evaluation Supervisory Leadership Consultant Roles Problem-Identification Survey Feedback Content Analysis Problem-Solving

  4. Reciprocal Feedback: Closing the Loop on Postactivity Surveys.

    Science.gov (United States)

    Watson, Richard A

    2015-01-01

    Those who conduct feedback surveys, which follow almost every CME presentation and medical-school lecture, would do well to offer participants' reciprocal feedback. That is, the course director should provide each survey respondent, on request, a brief summary of the comments received from this survey and the extent to which the recommendations will lead to objective improvements in the future. Surveyors who provide respondents with reciprocal feedback can expect heightened credibility, more reliable feedback in the future, and an added incentive to effect significant change for the better. Feedback has not circled all the way back until we have provided a succinct summary of results to those who have offered us their comments and suggestions. Let us close the loop; let reciprocal feedback become the last word in CME surveys.

  5. 75 FR 26345 - Agency Information Collection (Ethics Consultation Feedback Tool (ECFT)) New Enrollee Survey...

    Science.gov (United States)

    2010-05-11

    ... AFFAIRS Agency Information Collection (Ethics Consultation Feedback Tool (ECFT)) New Enrollee Survey.... 2900-New (VA Form 10-0502).'' SUPPLEMENTARY INFORMATION: Title: Ethics Consultation Feedback Tool (ECFT... experience during the Ethics Consultation Service. VA will be used the data to improve the process of...

  6. Assessing biosphere feedbacks on Earth System Processes

    Science.gov (United States)

    McElwain, Jennifer

    2016-04-01

    The evolution and ecology of plant life has been shaped by the direct and indirect influence of plate tectonics. Climatic change and environmental upheaval associated with the emplacement of large igneous provinces have triggered biosphere level ecological change, physiological modification and pulses of both extinction and origination. This talk will investigate the influence of large scale changes in atmospheric composition on plant ecophysiology at key intervals of the Phanerozoic. Furthermore, I will assess the extent to which plant ecophysiological response can in turn feedback on earth system processes such as the global hydrological cycle and biogeochemical cycling of nitrogen and carbon. Palaeo-atmosphere simulation experiments, palaeobotanical data and recent historical (last 50 years) data-model comparison will be used to address the extent to which plant physiological responses to atmospheric CO2 can modulate global climate change via biosphere level feedback.

  7. Feedback providing improvement strategies and reflection on feedback use: Effects on students' writing motivation, process, and performance

    NARCIS (Netherlands)

    H. Duijnhouwer; F.J. Prins; K.M. Stokking

    2012-01-01

    This study investigated the effects of feedback providing improvement strategies and a reflection assignment on students’ writing motivation, process, and performance. Students in the experimental feedback condition (n = 41) received feedback including improvement strategies, whereas students in the

  8. To change or not to change : a qualititative investigation into employees' experiences of a survey-feedback process in connection to an organizational level health intervention

    OpenAIRE

    Townsend, Martine Alexandra

    2016-01-01

    Organizational level interventions have proven habitually difficult to implement with successful outcomes. Recent process evaluations have identified key factors involved in successful outcomes such as participation, communication and manager behaviour. These factors have ultimately to do with fostering employee engagement and commitment to interventions. It is effectively up to the employees whether interventions achieve their goals or not. The objective of the present study was to investiga...

  9. Effects of Informative and Confirmatory Feedback on Brain Activation During Negative Feedback Processing

    Directory of Open Access Journals (Sweden)

    Yeon-Kyoung eWoo

    2015-06-01

    Full Text Available The current study compared the effects of informative and confirmatory feedback on brain activation during negative feedback processing. For confirmatory feedback trials, participants were informed that they had failed the task, whereas informative feedback trials presented task relevant information along with the notification of their failure. Fourteen male undergraduates performed a series of spatial-perceptual tasks and received feedback while their brain activity was recorded. During confirmatory feedback trials, greater activations in the amygdala, dorsal anterior cingulate cortex, and the thalamus (including the habenular were observed in response to incorrect responses. These results suggest that confirmatory feedback induces negative emotional reactions to failure. In contrast, informative feedback trials elicited greater activity in the dorsolateral prefrontal cortex (DLPFC when participants experienced failure. Further psychophysiological interaction (PPI analysis revealed a negative coupling between the DLPFC and the amygdala during informative feedback relative to confirmatory feedback trials. These findings suggest that providing task-relevant information could facilitate implicit down-regulation of negative emotions following failure.

  10. Survey Says: Using Teacher Feedback to Bolster Evaluation

    Science.gov (United States)

    Wiener, Ross; Lundy, Kasia

    2014-01-01

    Many of the leading private sector organizations have for years embraced a survey approach to improving products, services, and internal policies and processes. Like these successful private sector businesses, school systems can utilize a similar survey-based approach to improving teacher evaluation. Here, the authors provide and outline some…

  11. Feedback Specificity, Information Processing, and Transfer of Training

    Science.gov (United States)

    Goodman, Jodi S.; Wood, Robert E.; Chen, Zheng

    2011-01-01

    This study examines the effects of feedback specificity on transfer of training and the mechanisms through which feedback can enhance or inhibit transfer. We used concurrent verbal protocol methodology to elicit and operationalize the explicit information processing activities used by 48 trainees performing the Furniture Factory computer…

  12. Feedback Specificity, Information Processing, and Transfer of Training

    Science.gov (United States)

    Goodman, Jodi S.; Wood, Robert E.; Chen, Zheng

    2011-01-01

    This study examines the effects of feedback specificity on transfer of training and the mechanisms through which feedback can enhance or inhibit transfer. We used concurrent verbal protocol methodology to elicit and operationalize the explicit information processing activities used by 48 trainees performing the Furniture Factory computer…

  13. Feedback Providing Improvement Strategies and Reflection on Feedback Use: Effects on Students' Writing Motivation, Process, and Performance

    Science.gov (United States)

    Duijnhouwer, Hendrien; Prins, Frans J.; Stokking, Karel M.

    2012-01-01

    This study investigated the effects of feedback providing improvement strategies and a reflection assignment on students' writing motivation, process, and performance. Students in the experimental feedback condition (n = 41) received feedback including improvement strategies, whereas students in the control feedback condition (n = 41) received…

  14. Effects of intrinsic motivation on feedback processing during learning.

    Science.gov (United States)

    DePasque, Samantha; Tricomi, Elizabeth

    2015-10-01

    Learning commonly requires feedback about the consequences of one's actions, which can drive learners to modify their behavior. Motivation may determine how sensitive an individual might be to such feedback, particularly in educational contexts where some students value academic achievement more than others. Thus, motivation for a task might influence the value placed on performance feedback and how effectively it is used to improve learning. To investigate the interplay between intrinsic motivation and feedback processing, we used functional magnetic resonance imaging (fMRI) during feedback-based learning before and after a novel manipulation based on motivational interviewing, a technique for enhancing treatment motivation in mental health settings. Because of its role in the reinforcement learning system, the striatum is situated to play a significant role in the modulation of learning based on motivation. Consistent with this idea, motivation levels during the task were associated with sensitivity to positive versus negative feedback in the striatum. Additionally, heightened motivation following a brief motivational interview was associated with increases in feedback sensitivity in the left medial temporal lobe. Our results suggest that motivation modulates neural responses to performance-related feedback, and furthermore that changes in motivation facilitate processing in areas that support learning and memory.

  15. Performance Measure as Feedback Variable in Image Processing

    Directory of Open Access Journals (Sweden)

    Ristić Danijela

    2006-01-01

    Full Text Available This paper extends the view of image processing performance measure presenting the use of this measure as an actual value in a feedback structure. The idea behind is that the control loop, which is built in that way, drives the actual feedback value to a given set point. Since the performance measure depends explicitly on the application, the inclusion of feedback structures and choice of appropriate feedback variables are presented on example of optical character recognition in industrial application. Metrics for quantification of performance at different image processing levels are discussed. The issues that those metrics should address from both image processing and control point of view are considered. The performance measures of individual processing algorithms that form a character recognition system are determined with respect to the overall system performance.

  16. Ocean feedback to tropical cyclones: Climatology and processes

    Digital Repository Service at National Institute of Oceanography (India)

    Jullien, S.; Marchesiello, P.; Menkes, C.E.; Lefevre, J.; Jourdain, N.C.; Samson, G.; Lengaigne, M.

    is not instantaneous but accumulated over time within the TC inner-core. These results thus contradict the classical evaporation-wind feedback process as being essential to intensification and rather emphasize the role of macro-scale dynamics...

  17. Cultural influences on social feedback processing of character traits

    Directory of Open Access Journals (Sweden)

    Christoph W Korn

    2014-04-01

    Full Text Available Cultural differences are generally explained by how people see themselves in relation to social interaction partners. While Western culture emphasizes independence, East Asian culture emphasizes interdependence. Despite this focus on social interactions, it remains elusive how people from different cultures process feedback on their own (and on others' character traits. Here, participants of either German or Chinese origin engaged in a face-to-face interaction. Consequently, they updated their self- and other-ratings of 80 character traits (e.g., polite, pedantic after receiving feedback from their interaction partners. To exclude potential confounds, we obtained data from German and Chinese participants in Berlin (functional magnetic resonance imaging and in Beijing (behavior. We tested cultural influences on social conformity, positivity biases, and self-related neural activity. First, Chinese conformed more to social feedback than Germans (i.e., Chinese updated their trait ratings more. Second, regardless of culture, participants processed self- and other-related feedback in a positively biased way (i.e., they updated more toward desirable than toward undesirable feedback. Third, changes in self-related medial prefrontal cortex activity were greater in Germans than in Chinese during feedback processing. By investigating conformity, positivity biases, and self-related activity in relation to feedback obtained in a real-life interaction, we provide an essential step towards a unifying framework for understanding the diversity of human culture.

  18. Neural Correlates of Feedback Processing in Decision Making under Risk

    Directory of Open Access Journals (Sweden)

    Beate eSchuermann

    2012-07-01

    Full Text Available Introduction. Event-related brain potentials (ERP provide important information about the sensitivity of the brain to process varying risks. The aim of the present study was to determine how different risk levels are reflected in decision-related ERPs, namely the feedback-related negativity (FRN and the P300. Material and Methods. 20 participants conducted a probabilistic two-choice gambling task while an electroencephalogram was recorded. Choices were provided between a low-risk option yielding low rewards and low losses and a high-risk option yielding high rewards and high losses. While options differed in expected risks, they were equal in expected values and in feedback probabilities. Results. At the behavioral level, participants were generally risk-averse but modulated their risk-taking behavior according to reward history. An early positivity (P200 was enhanced on negative feedbacks in high-risk compared to low-risk options. With regard to the FRN, there were significant amplitude differences between positive and negative feedbacks in high-risk options, but not in low-risk options. While the FRN on negative feedbacks did not vary with decision riskiness, reduced amplitudes were found for positive feedbacks in high-risk relative to low-risk choices. P300 amplitudes were larger in high-risk decisions, and in an additive way, after negative compared to positive feedback. Discussion. The present study revealed significant influences of risk and valence processing on ERPs. FRN findings suggest that the reward prediction error signal is increased after high-risk decisions. The increased P200 on negative feedback in risky decisions suggests that large negative prediction errors are processed as early as in the P200 time range. The later P300 amplitude is sensitive to feedback valence as well as to the risk of a decision. Thus, the P300 carries additional information for reward processing, mainly the enhanced motivational significance of risky

  19. Assessing Postgraduate Student Perceptions and Measures of Learning in a Peer Review Feedback Process

    Science.gov (United States)

    Simpson, Genevieve; Clifton, Julian

    2016-01-01

    Peer review feedback, developed to assist students with increasing the quality of group reports and developing peer review skills, was added to a master's level Climate Change Policy and Planning unit. A pre- and post-survey was conducted to determine whether students found the process a valuable learning opportunity: 87% of students responding to…

  20. La medida del feedback laboral en las organizaciones : adaptación del cuestionario Job Feedback Survey

    OpenAIRE

    García Álvarez, Ana Isabel; Ovejero Bernal, Anastasio

    1998-01-01

    Las organizaciones utilizan el feedback laboral para la socialización, entrenamiento, mejora del desempeño y dirección de sus miembros. En el presente trabajo se examinan las investigaciones que han culminado con el desarrollo del cuestionario Job Feedback Survey (Herold y Parsons, 1985) para medir el feedback laboral y así poder estudiar su impacto sobre la conducta del trabajador. El objetivo de la investigación es la traducción y adaptación de este cuestionario a nuestro país para utilizar...

  1. PROVIDING THE STUDENTS WITH EFFECTIVE FEEDBACK IN THE WRITING PROCESS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    This paper focuses on providing effective feedback for the students in the writing process.Excessivemarking is defective as it reduces their motivation,whereas minimal marking is recommended as itimproves their inner drive for writing.In addition,there are other forms of feedback,such as peerfeedback,comments and face-to-face discussions.The students are required to act on the feedback totheir own advantage.It has been proved that the proposed correcting method is time-saving,chal-lenging and efficient.

  2. Process for Reviewing Survey Protocols

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document describes the process for conducting two types of reviews of survey protocols. A quick assessment is used to acknowledge and describe to potential...

  3. Topic: Catchment system dynamics: Processes and feedbacks

    Science.gov (United States)

    Keesstra, Saskia

    2015-04-01

    In this meeting we can talk about my main expertise: the focus of my research ocus revolves around understanding catchment system dynamics in a holistic way by incorporating both processes on hillslopes as well as in the river channel. Process knowledge enables explanation of the impact of natural and human drivers on the catchment systems and which consequences these drivers have for water and sediment connectivity. Improved understanding of the catchment sediment and water dynamics will empower sustainable land and river management and mitigate soil threats like erosion and off-side water and sediment accumulation with the help of nature's forces. To be able to understand the system dynamics of a catchment, you need to study the catchment system in a holistic way. In many studies only the hillslopes or even plots are studied; or only the channel. However, these systems are connected and should be evaluated together. When studying a catchment system any intervention to the system will create both on- as well as off sites effects, which should especially be taken into account when transferring science into policy regulations or management decisions.

  4. Rapid feedback processing in human nucleus accumbens and motor thalamus

    NARCIS (Netherlands)

    Schüller, T.; Gründler, T.O.J.; Jocham, G.; Klein, T.A.; Timmermann, L.; Visser-Vandewalle, V.E.R.M.; Kuhn, J.

    2015-01-01

    The nucleus accumbens (NAcc) and thalamus are integral parts in models of feedback processing. Deep brain stimulation (DBS) has been successfully employed to alleviate symptoms of psychiatric conditions including obsessive-compulsive disorder (OCD) and Tourette's syndrome (TS). Common target structu

  5. Do 360-degree feedback survey results relate to patient satisfaction measures?

    Science.gov (United States)

    Hageman, Michiel G J S; Ring, David C; Gregory, Paul J; Rubash, Harry E; Harmon, Larry

    2015-05-01

    There is evidence that feedback from 360-degree surveys-combined with coaching-can improve physician team performance and quality of patient care. The Physicians Universal Leadership-Teamwork Skills Education (PULSE) 360 is one such survey tool that is used to assess work colleagues' and coworkers' perceptions of a physician's leadership, teamwork, and clinical practice style. The Clinician & Group-Consumer Assessment of Healthcare Providers and System (CG-CAHPS), developed by the US Department of Health and Human Services to serve as the benchmark for quality health care, is a survey tool for patients to provide feedback that is based on their recent experiences with staff and clinicians and soon will be tied to Medicare-based compensation of participating physicians. Prior research has indicated that patients and coworkers often agree in their assessment of physicians' behavioral patterns. The goal of the current study was to determine whether 360-degree, also called multisource, feedback provided by coworkers could predict patient satisfaction/experience ratings. A significant relationship between these two forms of feedback could enable physicians to take a more proactive approach to reinforce their strengths and identify any improvement opportunities in their patient interactions by reviewing feedback from team members. An automated 360-degree software process may be a faster, simpler, and less resource-intensive approach than telephoning and interviewing patients for survey responses, and it potentially could facilitate a more rapid credentialing or quality improvement process leading to greater fiscal and professional development gains for physicians. Our primary research question was to determine if PULSE 360 coworkers' ratings correlate with CG-CAHPS patients' ratings of overall satisfaction, recommendation of the physician, surgeon respect, and clarity of the surgeon's explanation. Our secondary research questions were to determine whether CG-CAHPS scores

  6. Information thermodynamics for feedback processes with the appearance of overshooting

    Science.gov (United States)

    Kwon, Chulan

    2017-04-01

    We investigate feedback processes with measurement-induced protocols for particular tasks that drive systems in specified directions in state spaces. We focus on mutual information as a measure of correlation between system and memory, which has been known to play a crucial role for the second law of information thermodynamics. The performance of task is enhanced in the early stage of driving, along with the decrease of correlation and mutual information due to the passage from initial measurement. However, we find that the performance is suppressed if the time of driving exceeds a threshold, which we call feedback overshooting. We find that a type of correlation, anticorrelation, between system and memory is built up as a result of overshooting and gives rise to regaining mutual information. We examine the effect of overshooting in detail from two examples. We study the Szilard engine for the task of work extraction. We also study a recurrent feedback with finite time interval for the task to reduce the mean square distance of a colloid below the value by thermal fluctuation. We find that recurrent feedback is stable only for a moderate range of time intervals and the intensity of feedback protocol. We discuss the problem of divergence of mutual information for error-free measurement.

  7. Online User Feedback in Early Phases of the Design Process: Lessons Learnt from Four Design Cases

    Directory of Open Access Journals (Sweden)

    Asbjørn Følstad

    2010-01-01

    Full Text Available Online user feedback, collected by means of internet survey tools, is a promising approach to obtain early user feedback on concepts and early prototypes. In this study, the collection and utilization of online user feedback was investigated in four design cases: all master student projects for industry clients involving seven student designers. A total of 272 user participants provided quantitative feedback. Half of these also provided qualitative feedback. One third of the qualitative feedback was perceived as useful by the student designers. The main usefulness of the feedback was related to strategic concept decisions rather than the interaction design of the early prototype. Lessons learnt are provided.

  8. Feedback loops from the Hubble Space Telescope data processing system

    Science.gov (United States)

    Fraquelli, Dorothy A.; Arquilla, Richard; Ellis, Tracy; Hamilton, Forrest C.; Holm, Albert; Kochte, Mark

    2002-12-01

    This paper presents an overview of the history and technology by which tools placed in the Hubble Space Telescope (HST) data processing pipeline were used to feedback information on observation execution to the scheduling system and observers. Because the HST is in a relatively low orbit, which imposes a number of constraints upon its observations, it operates in a carefully planned, fully automated mode. To substitute for direct observer involvement available at most ground-based observatories and to provide rapid feedback on failures that might affect future visits, the Space Telescope Science Institute (STScI) gradually evolved a system for screening science and engineering products during pipeline processing. The highly flexible HST data processing system (OPUS) allows tools to be introduced to use the content of FITS keywords to alert production staff to potential telescope and instrument performance failures. Staff members review the flagged data and, if appropriate, notify the observer and the scheduling staff so that they can resolve the problems and possibly repeat the failed observations. This kind of feedback loop represents a case study for other automated data collection systems where rapid response to certain quantifiable events in the data is required. Observatory operations staff can install processes to look for these events either in the production pipeline or in an associated pipeline into which the appropriate data are piped. That process can then be used to notify scientists to evaluate the data and decide upon a response or to automatically initiate a response.

  9. Just Another Student Survey?--Point-of-Contact Survey Feedback Enhances the Student Experience and Lets Researchers Gather Data

    Science.gov (United States)

    Lake, Warren; Boyd, William; Boyd, Wendy; Hellmundt, Suzi

    2017-01-01

    When student surveys are conducted within university environments, one outcome of feedback to the researcher is that it provides insight into the potential ways that curriculum can be modified and how content can be better delivered. However, the benefit to the current students undertaking the survey is not always evident. By modifying Biggs'…

  10. A survey on delayed feedback control of chaos

    Institute of Scientific and Technical Information of China (English)

    Yuping TIAN; Jiandong ZHU; Guanrong CHEN

    2005-01-01

    This paper introduces the basic idea and provides the mathematical formulation of the delayed feedback control (DFC) methodology, which has been widely used in chaos control. Stability analysis including the well-known odd number limitation of the DFC is reviewed. Some new developments in characterizing the limitation of the DFC are presented. Various modified DFC methods, which are developed in order to overcome the odd number limitation, are also described. Finally, some open problems in this research field are discussed.

  11. Feedback.

    Science.gov (United States)

    Richardson, Barbara K

    2004-12-01

    The emergency department provides a rich environment for diverse patient encounters, rapid clinical decision making, and opportunities to hone procedural skills. Well-prepared faculty can utilize this environment to teach residents and medical students and gain institutional recognition for their incomparable role and teamwork. Giving effective feedback is an essential skill for all teaching faculty. Feedback is ongoing appraisal of performance based on direct observation aimed at changing or sustaining a behavior. Tips from the literature and the author's experience are reviewed to provide formats for feedback, review of objectives, and elements of professionalism and how to deal with poorly performing students. Although the following examples pertain to medical student education, these techniques are applicable to the education of all adult learners, including residents and colleagues. Specific examples of redirection and reflection are offered, and pitfalls are reviewed. Suggestions for streamlining verbal and written feedback and obtaining feedback from others in a fast-paced environment are given. Ideas for further individual and group faculty development are presented.

  12. Processes controlling Southern Ocean cloud-climate feedbacks (Invited)

    Science.gov (United States)

    Kay, J. E.; Medeiros, B.; Hwang, Y.; Gettelman, A.

    2013-12-01

    We use a fully coupled climate model (CESM) to identify processes controlling intriguingly diverse Southern Ocean cloud feedbacks in response to increased greenhouse gas forcing. Modeled Southern Ocean cloud-climate feedbacks range from the most positive (enhancing greenhouse warming at ~40 degrees South) to the most negative (damping greenhouse warming at ~60 degrees South) on the planet. As greenhouse gas concentrations increase, Antarctic sea ice loss, warming, and a poleward stormtrack shift/sub-tropical expansion all modify Southern Ocean clouds. Our analysis shows that Southern Ocean clouds are controlled both by thermodynamics (cloud changes for a given subsidence rate) and by dynamics (changes in subsidence rates). Hinting at the importance of thermodynamics, absorbed shortwave radiation over the Southern Ocean is substantially more affected by increased greenhouse gas forcing than by a poleward stormtrack shift in the absence of greenhouse forcing. While we find CESM a useful tool, CESM has substantial Southern Ocean biases (e.g., excessive Antarctic sea ice, excessive absorbed shortwave radiation). Thus, we also assess the impact that these biases have on the realism of CESM Southern Ocean cloud-climate greenhouse feedbacks.

  13. Uncovering star formation feedback and magnetism in galaxies with radio continuum surveys

    Science.gov (United States)

    Tabatabaei, F. S.

    2017-03-01

    Recent studies show the importance of the star formation feedback in changing the energetic and structure of galaxies. Dissecting the physics of the feedback is hence crucial to understand the evolution of galaxies. Full polarization radio continuum surveys can be ideally performed to trace not only star formation but also the energetic components of the interstellar medium (ISM), the magnetic fields and cosmic ray electrons. Using the SKA precursors, we investigate the effect of the massive star formation on the ISM energy balance in nearby galaxies. Our multi-scale and multi-frequency surveys show that cosmic rays are injected in star forming regions and lose energy propagating away from their birth place. Due to the star formation feedback, cosmic ray electron population becomes younger and more energetic. Star formation also amplifies the turbulent magnetic field inserting a high pressure which is important in energy balance in the ISM and structure formation in the host galaxy.

  14. Uncovering star formation feedback and magnetism in galaxies with radio continuum surveys

    CERN Document Server

    Tabatabaei, Fatemeh S

    2016-01-01

    Recent studies show the importance of the star formation feedback in changing the energetic and structure of galaxies. Dissecting the physics of the feedback is hence crucial to understand the evolution of galaxies. Full polarization radio continuum surveys can be ideally performed to trace not only star formation but also the energetic components of the interstellar medium (ISM), the magnetic fields and cosmic ray electrons. Using the SKA precursors, we investigate the effect of the massive star formation on the ISM energy balance in nearby galaxies. Our multi-scale and multi-frequency surveys show that cosmic rays are injected in star forming regions and lose energy propagating away from their birth place. Due to the star formation feedback, cosmic ray electron population becomes younger and more energetic. Star formation also amplifies the turbulent magnetic field inserting a high pressure which is important in energy balance in the ISM and structure formation in the host galaxy.

  15. Impaired implicit learning and feedback processing after stroke.

    Science.gov (United States)

    Lam, J M; Globas, C; Hosp, J A; Karnath, H-O; Wächter, T; Luft, A R

    2016-02-01

    The ability to learn is assumed to support successful recovery and rehabilitation therapy after stroke. Hence, learning impairments may reduce the recovery potential. Here, the hypothesis is tested that stroke survivors have deficits in feedback-driven implicit learning. Stroke survivors (n=30) and healthy age-matched control subjects (n=21) learned a probabilistic classification task with brain activation measured using functional magnetic resonance imaging in a subset of these individuals (17 stroke and 10 controls). Stroke subjects learned slower than controls to classify cues. After being rewarded with a smiley face, they were less likely to give the same response when the cue was repeated. Stroke subjects showed reduced brain activation in putamen, pallidum, thalamus, frontal and prefrontal cortices and cerebellum when compared with controls. Lesion analysis identified those stroke survivors as learning-impaired who had lesions in frontal areas, putamen, thalamus, caudate and insula. Lesion laterality had no effect on learning efficacy or brain activation. These findings suggest that stroke survivors have deficits in reinforcement learning that may be related to dysfunctional processing of feedback-based decision-making, reward signals and working memory.

  16. Neural correlates of anticipation and processing of performance feedback in social anxiety.

    Science.gov (United States)

    Heitmann, Carina Y; Peterburs, Jutta; Mothes-Lasch, Martin; Hallfarth, Marlit C; Böhme, Stephanie; Miltner, Wolfgang H R; Straube, Thomas

    2014-12-01

    Fear of negative evaluation, such as negative social performance feedback, is the core symptom of social anxiety. The present study investigated the neural correlates of anticipation and perception of social performance feedback in social anxiety. High (HSA) and low (LSA) socially anxious individuals were asked to give a speech on a personally relevant topic and received standardized but appropriate expert performance feedback in a succeeding experimental session in which neural activity was measured during anticipation and presentation of negative and positive performance feedback concerning the speech performance, or a neutral feedback-unrelated control condition. HSA compared to LSA subjects reported greater anxiety during anticipation of negative feedback. Functional magnetic resonance imaging results showed deactivation of medial prefrontal brain areas during anticipation of negative feedback relative to the control and the positive condition, and medial prefrontal and insular hyperactivation during presentation of negative as well as positive feedback in HSA compared to LSA subjects. The results indicate distinct processes underlying feedback processing during anticipation and presentation of feedback in HSA as compared to LSA individuals. In line with the role of the medial prefrontal cortex in self-referential information processing and the insula in interoception, social anxiety seems to be associated with lower self-monitoring during feedback anticipation, and an increased self-focus and interoception during feedback presentation, regardless of feedback valence.

  17. Effects of Intrinsic Motivation on Feedback Processing During Learning

    OpenAIRE

    DePasque, Samantha; Tricomi, Elizabeth

    2015-01-01

    Learning commonly requires feedback about the consequences of one’s actions, which can drive learners to modify their behavior. Motivation may determine how sensitive an individual might be to such feedback, particularly in educational contexts where some students value academic achievement more than others. Thus, motivation for a task might influence the value placed on performance feedback and how effectively it is used to improve learning. To investigate the interplay between intrinsic mot...

  18. Feedback Processes [in Massive Star Formation]: A Theoretical Perspective

    CERN Document Server

    Mac Low, Mordecai-Mark

    2007-01-01

    I review the evidence for the importance of feedback from massive stars at small and large scales. The feedback mechanisms include accretion luminosity, ionizing radiation, collimated outflows, and stellar winds. The good news is that feedback doesn't entirely prevent the formation of massive stars, while the bad news is that we don't know what does limit their masses. Feedback from massive stars also influences their surroundings. I argue that this does not produce a triggering efficiency above unity, nor does it prevent lots of prompt star formation in GMCs, though it may preserve massive remnants of the clouds for many dynamical times.

  19. From Positivity to Negativity Bias: Ambiguity Affects the Neurophysiological Signatures of Feedback Processing.

    Science.gov (United States)

    Gibbons, Henning; Schnuerch, Robert; Stahl, Jutta

    2016-04-01

    Previous studies on the neurophysiological underpinnings of feedback processing almost exclusively used low-ambiguity feedback, which does not fully address the diversity of situations in everyday life. We therefore used a pseudo trial-and-error learning task to investigate ERPs of low- versus high-ambiguity feedback. Twenty-eight participants tried to deduce the rule governing visual feedback to their button presses in response to visual stimuli. In the blocked condition, the same two feedback words were presented across several consecutive trials, whereas in the random condition feedback was randomly drawn on each trial from sets of five positive and five negative words. The feedback-related negativity (FRN-D), a frontocentral ERP difference between negative and positive feedback, was significantly larger in the blocked condition, whereas the centroparietal late positive complex indicating controlled attention was enhanced for negative feedback irrespective of condition. Moreover, FRN-D in the blocked condition was due to increased reward positivity (Rew-P) for positive feedback, rather than increased (raw) FRN for negative feedback. Our findings strongly support recent lines of evidence that the FRN-D, one of the most widely studied signatures of reinforcement learning in the human brain, critically depends on feedback discriminability and is primarily driven by the Rew-P. A novel finding concerned larger frontocentral P2 for negative feedback in the random but not the blocked condition. Although Rew-P points to a positivity bias in feedback processing under conditions of low feedback ambiguity, P2 suggests a specific adaptation of information processing in case of highly ambiguous feedback, involving an early negativity bias. Generalizability of the P2 findings was demonstrated in a second experiment using explicit valence categorization of highly emotional positive and negative adjectives.

  20. A Combination of Outcome and Process Feedback Enhances Performance in Simulations of Child Sexual Abuse Interviews Using Avatars

    Directory of Open Access Journals (Sweden)

    Francesco Pompedda

    2017-09-01

    Full Text Available Simulated interviews in alleged child sexual abuse (CSA cases with computer-generated avatars paired with feedback improve interview quality. In the current study, we aimed to understand better the effect of different types of feedback in this context. Feedback was divided into feedback regarding conclusions about what happened to the avatar (outcome feedback and feedback regarding the appropriateness of question-types used by the interviewer (process feedback. Forty-eight participants each interviewed four different avatars. Participants were divided into four groups (no feedback, outcome feedback, process feedback, and a combination of both feedback types. Compared to the control group, interview quality was generally improved in all the feedback groups on all outcome variables included. Combined feedback produced the strongest effect on increasing recommended questions and correct conclusions. For relevant and neutral details elicited by the interviewers, no statistically significant differences were found between feedback types. For wrong details, the combination of feedback produced the strongest effect, but this did not differ from the other two feedback groups. Nevertheless, process feedback produced a better result compared to outcome feedback. The present study replicated previous findings regarding the effect of feedback in improving interview quality, and provided new knowledge on feedback characteristics that maximize training effects. A combination of process and outcome feedback showed the strongest effect in enhancing training in simulated CSA interviews. Further research is, however, needed.

  1. Feedback effects on students' writing motivation, process, and performance

    NARCIS (Netherlands)

    Duijnhouwer, H.

    2010-01-01

    Many students’ writing capacities remain insufficient during college years (Kellogg & Whiteford, 2009). Teachers try to improve students’ writing skills by providing them with feedback on their texts. Remarkably, research on the effects of feedback provided on written products is scarce (Graham &

  2. Learners' Processing, Uptake, and Retention of Corrective Feedback on Writing

    Science.gov (United States)

    Storch, Neomy; Wigglesworth, Gillian

    2010-01-01

    The literature on corrective feedback (CF) that second language writers receive in response to their grammatical and lexical errors is plagued by controversies and conflicting findings about the merits of feedback. Although more recent studies suggest that CF is valuable (e.g., Bitchener, 2008; Sheen, 2007), it is still not clear whether direct or…

  3. Feedback effects on students' writing motivation, process, and performance

    NARCIS (Netherlands)

    Duijnhouwer, H.

    2010-01-01

    Many students’ writing capacities remain insufficient during college years (Kellogg & Whiteford, 2009). Teachers try to improve students’ writing skills by providing them with feedback on their texts. Remarkably, research on the effects of feedback provided on written products is scarce (Graham & Pe

  4. Nursing home administrators' perspectives on a study feedback report: a cross sectional survey.

    Science.gov (United States)

    Boström, Anne-Marie; Cranley, Lisa A; Hutchinson, Alison M; Cummings, Greta G; Norton, Peter G; Estabrooks, Carole A

    2012-09-13

    This project is part of the Translating Research in Elder Care (TREC) program of research, a multi-level and longitudinal research program being conducted in 36 nursing homes in three Canadian Prairie Provinces. The overall goal of TREC is to improve the quality of care for older persons living in nursing homes and the quality of work life for care providers. The purpose of this paper is to report on development and evaluation of facility annual reports (FARs) from facility administrators' perspectives on the usefulness, meaningfulness, and understandability of selected data from the TREC survey. A cross sectional survey design was used in this study. The feedback reports were developed in collaboration with participating facility administrators. FARs presented results in four contextual areas: workplace culture, feedback processes, job satisfaction, and staff burnout. Six weeks after FARs were mailed to each administrator, we conducted structured telephone interviews with administrators to elicit their evaluation of the FARs. Administrators were also asked if they had taken any actions as a result of the FAR. Descriptive and inferential statistics, as well as content analysis for open-ended questions, were used to summarize findings. Thirty-one facility administrators (representing thirty-two facilities) participated in the interviews. Six administrators had taken action and 18 were planning on taking action as a result of FARs. The majority found the four contextual areas addressed in FAR to be useful, meaningful, and understandable. They liked the comparisons made between data from years one and two and between their facility and other TREC study sites in their province. Twenty-two indicated that they would like to receive information on additional areas such as aggressive behaviours of residents and information sharing. Twenty-four administrators indicated that FARs contained enough information, while eight found FARs 'too short'. Administrators who reported

  5. Nursing home administrators’ perspectives on a study feedback report: a cross sectional survey

    Directory of Open Access Journals (Sweden)

    Boström Anne-Marie

    2012-09-01

    Full Text Available Abstract Background This project is part of the Translating Research in Elder Care (TREC program of research, a multi-level and longitudinal research program being conducted in 36 nursing homes in three Canadian Prairie Provinces. The overall goal of TREC is to improve the quality of care for older persons living in nursing homes and the quality of work life for care providers. The purpose of this paper is to report on development and evaluation of facility annual reports (FARs from facility administrators’ perspectives on the usefulness, meaningfulness, and understandability of selected data from the TREC survey. Methods A cross sectional survey design was used in this study. The feedback reports were developed in collaboration with participating facility administrators. FARs presented results in four contextual areas: workplace culture, feedback processes, job satisfaction, and staff burnout. Six weeks after FARs were mailed to each administrator, we conducted structured telephone interviews with administrators to elicit their evaluation of the FARs. Administrators were also asked if they had taken any actions as a result of the FAR. Descriptive and inferential statistics, as well as content analysis for open-ended questions, were used to summarize findings. Results Thirty-one facility administrators (representing thirty-two facilities participated in the interviews. Six administrators had taken action and 18 were planning on taking action as a result of FARs. The majority found the four contextual areas addressed in FAR to be useful, meaningful, and understandable. They liked the comparisons made between data from years one and two and between their facility and other TREC study sites in their province. Twenty-two indicated that they would like to receive information on additional areas such as aggressive behaviours of residents and information sharing. Twenty-four administrators indicated that FARs contained enough information, while eight

  6. Do 360-degree Feedback Survey Results Relate to Patient Satisfaction Measures?

    OpenAIRE

    Hageman, Michiel G. J. S.; Ring, David C.; Gregory, Paul J.; Rubash, Harry E.; Harmon, Larry

    2014-01-01

    Background There is evidence that feedback from 360-degree surveys—combined with coaching—can improve physician team performance and quality of patient care. The Physicians Universal Leadership-Teamwork Skills Education (PULSE) 360 is one such survey tool that is used to assess work colleagues’ and coworkers’ perceptions of a physician’s leadership, teamwork, and clinical practice style. The Clinician & Group-Consumer Assessment of Healthcare Providers and System (CG-CAHPS), developed by the ...

  7. Gathering Feedback from Early-Career Faculty: Speaking with and Surveying Agricultural Faculty Members about Research Data

    Directory of Open Access Journals (Sweden)

    Sarah C. Williams

    2013-10-01

    Full Text Available In spring 2013, the Life Sciences Data Services Librarian at the University of Illinois at Urbana-Champaign gave a data management presentation to early-career, agricultural faculty members participating in a selective program designed to help them succeed in the tenure process. After the presentation, the participants were invited to complete an online survey that included questions on how well informed and prepared they feel about funding agencies’ data requirements, what data challenges they face, and how the library can help with new or improved services in this area. The presentation discussion and survey responses suggested value in offering data training specifically for agricultural graduate students and research assistants and compiling examples of data management plans from successful grant proposals. Despite the small number of participants, the feedback provides an interesting glimpse into data management from the perspective of early-career faculty.

  8. Audio Feedback -- Better Feedback?

    Science.gov (United States)

    Voelkel, Susanne; Mello, Luciane V.

    2014-01-01

    National Student Survey (NSS) results show that many students are dissatisfied with the amount and quality of feedback they get for their work. This study reports on two case studies in which we tried to address these issues by introducing audio feedback to one undergraduate (UG) and one postgraduate (PG) class, respectively. In case study one…

  9. Leadership development in a professional medical society using 360-degree survey feedback to assess emotional intelligence.

    Science.gov (United States)

    Gregory, Paul J; Robbins, Benjamin; Schwaitzberg, Steven D; Harmon, Larry

    2016-12-30

    The current research evaluated the potential utility of a 360-degree survey feedback program for measuring leadership quality in potential committee leaders of a professional medical association (PMA). Emotional intelligence as measured by the extent to which self-other agreement existed in the 360-degree survey ratings was explored as a key predictor of leadership quality in the potential leaders. A non-experimental correlational survey design was implemented to assess the variation in leadership quality scores across the sample of potential leaders. A total of 63 of 86 (76%) of those invited to participate did so. All potential leaders received feedback from PMA Leadership, PMA Colleagues, and PMA Staff and were asked to complete self-ratings regarding their behavior. Analyses of variance revealed a consistent pattern of results as Under-Estimators and Accurate Estimators-Favorable were rated significantly higher than Over-Estimators in several leadership behaviors. Emotional intelligence as conceptualized in this study was positively related to overall performance ratings of potential leaders. The ever-increasing roles and potential responsibilities for PMAs suggest that these organizations should consider multisource performance reviews as these potential future PMA executives rise through their organizations to assume leadership positions with profound potential impact on healthcare. The current findings support the notion that potential leaders who demonstrated a humble pattern or an accurate pattern of self-rating scored significantly higher in their leadership, teamwork, and interpersonal/communication skills than those with an aggrandizing self-rating.

  10. A Pharmaceutical Bioethics Consultation Service: Six-Year Descriptive Characteristics and Results of a Feedback Survey.

    Science.gov (United States)

    Van Campen, Luann E; Allen, Albert J; Watson, Susan B; Therasse, Donald G

    2015-04-03

    Background: Bioethics consultations are conducted in varied settings, including hospitals, universities, and other research institutions, but there is sparse information about bioethics consultations conducted in corporate settings such as pharmaceutical companies. The purpose of this article is to describe a bioethics consultation service at a pharmaceutical company, to report characteristics of consultations completed by the service over a 6-year period, and to share results of a consultation feedback survey. Methods: Data on the descriptive characteristics of bioethics consultations were collected from 2008 to 2013 and analyzed in Excel 2007. Categorical data were analyzed via the pivot table function, and time-based variables were analyzed via formulas. The feedback survey was administered to consultation requesters from 2009 to 2012 and also analyzed in Excel 2007. Results: Over the 6-year period, 189 bioethics consultations were conducted. The number of consultations increased from five per year in 2008 to approximately one per week in 2013. During this time, the format of the consultation service was changed from a committee-only approach to a tiered approach (tailored to the needs of the case). The five most frequent topics were informed consent, early termination of a clinical trial, benefits and risks, human biological samples, and patient rights. The feedback survey results suggest the consultation service is well regarded overall and viewed as approachable, helpful, and responsive. Conclusions: Pharmaceutical bioethics consultation is a unique category of bioethics consultation that primarily focuses on pharmaceutical research and development but also touches on aspects of clinical ethics, business ethics, and organizational ethics. Results indicate there is a demand for a tiered bioethics consultation service within this pharmaceutical company and that advice was valued. This company's experience indicates that a bioethics consultation service raises

  11. Assessing the Quality of Feedback in the Peer-Review Process

    Science.gov (United States)

    Dobele, A. R.

    2015-01-01

    The feedback provided to authors by reviewers as part of a double-blind peer-review process was examined for two Australian conferences, one special international edition book and six international special edition journals (originating in the UK). The research sought to identify consistency of decision-making and the effectiveness of feedback for…

  12. Multivoxel Patterns Reveal Functionally Differentiated Networks Underlying Auditory Feedback Processing of Speech

    DEFF Research Database (Denmark)

    Zheng, Zane Z.; Vicente-Grabovetsky, Alejandro; MacDonald, Ewen N.

    2013-01-01

    within a multivoxel pattern analysis framework, that this sensorimotor process is supported by functionally differentiated brain networks. During scanning, a real-time speech-tracking system was used to deliver two acoustically different types of distorted auditory feedback or unaltered feedback while...

  13. Analysing Feedback Processes in an Online Teaching and Learning Environment: An Exploratory Study

    Science.gov (United States)

    Espasa, Anna; Meneses, Julio

    2010-01-01

    Within the constructivist framework of online distance education the feedback process is considered a key element in teachers' roles because it can promote the regulation of learning. Therefore, faced with the need to guide and train teachers in the kind of feedback to provide and how to provide it, we establish three aims for this research:…

  14. Constructing a survey over time: Audio-visual feedback and theatre sketches in rural Mali

    Directory of Open Access Journals (Sweden)

    Véronique Hertrich

    2011-10-01

    Full Text Available Knowledge dissemination is an emerging issue in population studies, both in terms of ethics and data quality. The challenge is especially important in long term follow-up surveys and it requires methodological imagination when the population is illiterate. The paper presents the dissemination project developed in a demographic surveillance system implemented in rural Mali over the last 20 years. After basic experience of document transfer, the feedback strategy was developed through audiovisual shows and theatre sketches. The advantages and drawbacks of these media are discussed, in terms of scientific communication and the construction of dialogue with the target population.

  15. The effect of process delay on dynamical behaviors in a self-feedback nonlinear oscillator

    Science.gov (United States)

    Yao, Chenggui; Ma, Jun; Li, Chuan; He, Zhiwei

    2016-10-01

    The delayed feedback loops play a crucial role in the stability of dynamical systems. The effect of process delay in feedback is studied numerically and theoretically in the delayed feedback nonlinear systems including the neural model, periodic system and chaotic oscillator. The process delay is of key importance in determining the evolution of systems, and the rich dynamical phenomena are observed. By introducing a process delay, we find that it can induce bursting electric activities in the neural model. We demonstrate that this novel regime of amplitude death also exists in the parameter space of feedback strength and process delay for the periodic system and chaotic oscillator. Our results extend the effect of process delay in the paper of Zou et al.(2013) where the process delay can eliminate the amplitude death of the coupled nonlinear systems.

  16. Language-based social feedback processing with randomized "senders": An ERP study.

    Science.gov (United States)

    Schindler, Sebastian; Kissler, Johanna

    2017-02-06

    Recently, several event-related potential (ERP) studies investigated the impact of sender attributions on language-based social feedback processing. Results showed very early responses to the social context, while interactions or effects of emotional content started later. However, in these studies, sender attribution was varied across blocks, possibly inducing unspecific, anticipatory effects. Here, who was giving feedback was disclosed simultaneously with the decision itself. Participants' ERPs differentiated between attributed senders starting with the early posterior negativity. P3 and late positive potential (LPP) amplitudes were also enlarged for the "human sender". Emotion effects occurred in the P3 and LPP time windows. Further, we found an interaction on the P3: "Human" emotional feedback was selectively amplified. Source analysis localized enhanced processing of "human"-generated feedback in visual areas from around 300 ms after feedback onset and from 400 ms also in temporal regions. Enhancement of "human" emotional feedback resulted from increased activations in the left visual word form area. These findings highlight that decoding who is giving feedback precedes content processing, both in blocked and in randomly alternating situations. Further, in quasi-realistic social contexts, processing of emotional content is selectively amplified. Finally, involvement of semantic language processing structures indicates reintegration of words in a salient context.

  17. Advanced process monitoring and feedback control to enhance cell culture process production and robustness.

    Science.gov (United States)

    Zhang, An; Tsang, Valerie Liu; Moore, Brandon; Shen, Vivian; Huang, Yao-Ming; Kshirsagar, Rashmi; Ryll, Thomas

    2015-12-01

    It is a common practice in biotherapeutic manufacturing to define a fixed-volume feed strategy for nutrient feeds, based on historical cell demand. However, once the feed volumes are defined, they are inflexible to batch-to-batch variations in cell growth and physiology and can lead to inconsistent productivity and product quality. In an effort to control critical quality attributes and to apply process analytical technology (PAT), a fully automated cell culture feedback control system has been explored in three different applications. The first study illustrates that frequent monitoring and automatically controlling the complex feed based on a surrogate (glutamate) level improved protein production. More importantly, the resulting feed strategy was translated into a manufacturing-friendly manual feed strategy without impact on product quality. The second study demonstrates the improved process robustness of an automated feed strategy based on online bio-capacitance measurements for cell growth. In the third study, glucose and lactate concentrations were measured online and were used to automatically control the glucose feed, which in turn changed lactate metabolism. These studies suggest that the auto-feedback control system has the potential to significantly increase productivity and improve robustness in manufacturing, with the goal of ensuring process performance and product quality consistency.

  18. Information thermodynamics for a multi-feedback process with time delay

    Science.gov (United States)

    Kwon, Chulan; Um, Jaegon; Park, Hyunggyu

    2017-01-01

    We investigate a measurement-feedback process of repeated operations with time delay. During a finite-time interval, measurement on the system is performed and the feedback protocol derived from the measurement outcome is applied with time delay. This protocol is maintained into the next interval until a new protocol from the next measurement is applied. Unlike a feedback process without delay, both memories associated with previous and present measurement outcomes are involved in the system dynamics, which naturally brings forth a joint system described by a system state and two memory states. The thermodynamic second law provides a lower bound for heat flow into a thermal reservoir by the (3-state) Shannon entropy change of the joint system. However, as the feedback protocol depends on memory states sequentially, we can deduce a tighter bound for heat flow by integrating out irrelevant memory states during dynamics. As a simple example, we consider the so-called cold damping feedback process where the velocity of a particle is measured and a dissipative feedback protocol is applied to decelerate the particle. We confirm that the heat flow is well above the tightest bound. We also examine the long-time limit of this feedback process, which turns out to exhibit an interesting instability transition as well as heating by controlling parameters such as measurement errors, time interval, protocol strength, and time delay length. We discuss the underlying mechanism for instability and heating, which might be unavoidable in reality.

  19. Factors influencing trainers' feedback-giving behavior: a cross-sectional survey

    NARCIS (Netherlands)

    Pelgrim, E.A.M.; Kramer, A.W.M.; Mokkink, H.G.A.; Vleuten, C.P.M. van der

    2014-01-01

    BACKGROUND: The literature provides some insight into the role of feedback givers, but little information about within-trainer factors influencing 'feedback-giving behaviours'. We looked for relationships between characteristics of feedback givers (self-efficacy, task perception, neuroticism,

  20. Role of inhibitory feedback for information processing in thalamocortical circuits

    Science.gov (United States)

    Mayer, Jörg; Schuster, Heinz Georg; Claussen, Jens Christian

    2006-03-01

    The information transfer in the thalamus is blocked dynamically during sleep, in conjunction with the occurrence of spindle waves. In order to describe the dynamic mechanisms which control the sensory transfer of information, it is necessary to have a qualitative model for the response properties of thalamic neurons. As the theoretical understanding of the mechanism remains incomplete, we analyze two modeling approaches for a recent experiment by Le Masson [Nature (London) 417, 854 (2002)] on the thalamocortical loop. We use a conductance based model in order to motivate an extension of the Hindmarsh-Rose model, which mimics experimental observations of Le Masson Typically, thalamic neurons posses two different firing modes, depending on their membrane potential. At depolarized potentials, the cells fire in a single spike mode and relay synaptic inputs in a one-to-one manner to the cortex. If the cell gets hyperpolarized, T -type calcium currents generate burst-mode firing which leads to a decrease in the spike transfer. In thalamocortical circuits, the cell membrane gets hyperpolarized by recurrent inhibitory feedback loops. In the case of reciprocally coupled excitatory and inhibitory neurons, inhibitory feedback leads to metastable self-sustained oscillations, which mask the incoming input, and thereby reduce the information transfer significantly.

  1. Momentum Driving: which physical processes dominate AGN feedback?

    CERN Document Server

    Ostriker, Jeremiah P; Ciotti, Luca; Novak, Gregory S; Proga, Daniel

    2010-01-01

    The deposition of mechanical feedback from a supermassive black hole (SMBH) in an active galactic nucleus (AGN) into the surrounding galaxy occurs via broad-line winds which must carry mass and radial momentum as well as energy. The effect can be summarized by the dimensionless parameter $\\eta=dot{M_outflow}/dot{M_accretion}= (2 \\epsilon_w c^2)/v_w^2$ where ($\\epslion_w \\equiv dot{E}_w/(dot{M_accretion} c^2)$) is the efficiency by which accreted matter is turned into wind energy in the disc surrounding the central SMBH. The outflowing mass and omentum are proportional to $\\eta$, and many prior treatments have essentially assumed that $\\eta=0$. We perform one- and two-dimensional simulations and find that the growth of the central SMBH is very sensitive to the inclusion of the mass and momentum driving but is insensitive to the assumed mechanical efficiency. For example in representative calculations, the omission of momentum and mass feedback leads to an hundred fold increase in the mass of the SMBH to over $...

  2. From Monologue to Dialogue: Improving Written Feedback Processes in Mass Higher Education

    Science.gov (United States)

    Nicol, David

    2010-01-01

    Student surveys across the world have highlighted that students are dissatisfied with the feedback they receive on their assignments and many institutions have been putting plans in place to address this issue. Much of this work has focused on improving the quality of written comments. This paper takes a different perspective. It argues that the…

  3. Effects of Person- and Process-Focused Feedback on Prosocial Behavior in Middle Childhood.

    Science.gov (United States)

    Dunsmore, Julie C

    2015-02-01

    Effects of person- and process-focused feedback, parental lay theories, and prosocial self-concept on children's prosocial behavior were investigated with 143 9- and 10-year-old children who participated in a single session. Parents reported entity (person-focused) and incremental (process-focused) beliefs related to prosocial behavior. Children completed measures of prosocial self-concept, then participated in a virtual online chat with child actors who asked for help with service projects. After completing the chat, children could assist with the service projects. In the first cohort, children were randomly assigned to receive person-focused, process-focused, or control feedback about sympathy. In the second cohort, with newly-recruited families, children received no feedback. When given process-focused feedback, children spent less time spent helping and worked on fewer service projects. When given no feedback, children spent less time helping when parents held incremental (process-focused) beliefs. Children with higher prosocial self-concept who received no feedback worked on more service projects.

  4. Electrophysiological responses of feedback processing are modulated by MAOA genotype in healthy male adolescents.

    Science.gov (United States)

    Ma, Ren; Jia, Huiqiao; Yi, Fei; Ming, Qingsen; Wang, Xiang; Gao, Yidian; Yi, Jinyao; Yao, Shuqiao

    2016-01-01

    A functional polymorphism in the promoter region of the monoamine oxidase A (MAOA) gene is closely related to aggression. Although previous studies suggested that impaired ability of feedback processing might be associated with aggressive behaviour, studies concerning the MAOA gene-related aggression rarely focused on the link between MAOA gene and feedback processing. We therefore sought to investigate the effect of MAOA genotype on electrophysiological responses of feedback processing in 72 healthy male adolescents during a simple monetary gambling task. Feedback processing was investigated by measuring the feedback-related negativity (FRN) and the P300 as electrophysiological markers. We observed a decreased electrophysiological response of the loss-gain difference waves from 250 to 350 ms (dFRN) in individuals with the lower activity alleles (MAOA-L) during the task, an effect that was driven primarily by the considerably altered response to monetary gains. The reduced dFRN in MAOA-L group might indicate poor ability to learn from feedback, which is followed by adjusting future behaviour. And MAOA-L carriers exhibited lower P300 compared with subjects with higher activity alleles (MAOA-H), which suggested fewer attentional resources were allocated to feedback processing. In addition, MAOA-L carriers demonstrated higher aggression and the aggression were inversely correlated with dFRN across two groups; further analyses suggested that dFRN mediated the MAOA genotype-aggression relationship. Consequently, we concluded that it might be the altered feedback processing that makes MAOA-L carriers more vulnerable to aggressive behaviour.

  5. ℋ∞ constant gain state feedback stabilization of stochastic hybrid systems with Wiener process

    Directory of Open Access Journals (Sweden)

    E. K. Boukas

    2004-01-01

    Full Text Available This paper considers the stabilization problem of the class of continuous-time linear stochastic hybrid systems with Wiener process. The ℋ∞ state feedback stabilization problem is treated. A state feedback controller with constant gain that does not require access to the system mode is designed. LMI-based conditions are developed to design the state feedback controller with constant gain that stochastically stabilizes the studied class of systems and, at the same time, achieve the disturbance rejection of a desired level. The minimum disturbance rejection is also determined. Numerical examples are given to show the usefulness of the proposed results.

  6. The MAGNUM survey: positive feedback in the nuclear region of NGC 5643 suggested by MUSE

    Science.gov (United States)

    Cresci, G.; Marconi, A.; Zibetti, S.; Risaliti, G.; Carniani, S.; Mannucci, F.; Gallazzi, A.; Maiolino, R.; Balmaverde, B.; Brusa, M.; Capetti, A.; Cicone, C.; Feruglio, C.; Bland-Hawthorn, J.; Nagao, T.; Oliva, E.; Salvato, M.; Sani, E.; Tozzi, P.; Urrutia, T.; Venturi, G.

    2015-10-01

    We study the ionization and kinematics of the ionized gas in the nuclear region of the barred Seyfert 2 galaxy NGC 5643 using MUSE integral field observations in the framework of the Measuring Active Galactic Nuclei Under MUSE Microscope (MAGNUM) survey. The data were used to identify regions with different ionization conditions and to map the gas density and the dust extinction. We find evidence for a double-sided ionization cone, possibly collimated by a dusty structure surrounding the nucleus. At the center of the ionization cone, outflowing ionized gas is revealed as a blueshifted, asymmetric wing of the [OIII] emission line, up to projected velocity v10 ~ -450 km s-1. The outflow is also seen as a diffuse, low-luminosity radio and X-ray jet, with similar extension. The outflowing material points in the direction of two clumps characterized by prominent line emission with spectra typical of HII regions, located at the edge of the dust lane of the bar. We propose that the star formation in the clumps is due to positive feedback induced by gas compression by the nuclear outflow, providing the first candidate for outflow-induced star formation in a Seyfert-like, radio-quiet AGN. This suggests that positive feedback may be a relevant mechanism in shaping the black hole-host galaxy coevolution. This work is based on observations made at the European Southern Observatory, Paranal, Chile (ESO program 60.A-9339).

  7. The role of feed-forward and feedback processes for closed-loop prosthesis control

    Directory of Open Access Journals (Sweden)

    Saunders Ian

    2011-10-01

    Full Text Available Abstract Background It is widely believed that both feed-forward and feed-back mechanisms are required for successful object manipulation. Open-loop upper-limb prosthesis wearers receive no tactile feedback, which may be the cause of their limited dexterity and compromised grip force control. In this paper we ask whether observed prosthesis control impairments are due to lack of feedback or due to inadequate feed-forward control. Methods Healthy subjects were fitted with a closed-loop robotic hand and instructed to grasp and lift objects of different weights as we recorded trajectories and force profiles. We conducted three experiments under different feed-forward and feed-back configurations to elucidate the role of tactile feedback (i in ideal conditions, (ii under sensory deprivation, and (iii under feed-forward uncertainty. Results (i We found that subjects formed economical grasps in ideal conditions. (ii To our surprise, this ability was preserved even when visual and tactile feedback were removed. (iii When we introduced uncertainty into the hand controller performance degraded significantly in the absence of either visual or tactile feedback. Greatest performance was achieved when both sources of feedback were present. Conclusions We have introduced a novel method to understand the cognitive processes underlying grasping and lifting. We have shown quantitatively that tactile feedback can significantly improve performance in the presence of feed-forward uncertainty. However, our results indicate that feed-forward and feed-back mechanisms serve complementary roles, suggesting that to improve on the state-of-the-art in prosthetic hands we must develop prostheses that empower users to correct for the inevitable uncertainty in their feed-forward control.

  8. Acute stress modulates feedback processing in men and women: differential effects on the feedback-related negativity and theta and beta power.

    Directory of Open Access Journals (Sweden)

    Stella Banis

    Full Text Available Sex-specific prevalence rates in mental and physical disorders may be partly explained by sex differences in physiological stress responses. Neural networks that might be involved are those underlying feedback processing. Aim of the present EEG study was to investigate whether acute stress alters feedback processing, and whether stress effects differ between men and women. Male and female participants performed a gambling task, in a control and a stress condition. Stress was induced by exposing participants to a noise stressor. Brain activity was analyzed using both event-related potential and time-frequency analyses, measuring the feedback-related negativity (FRN and feedback-related changes in theta and beta oscillatory power, respectively. While the FRN and feedback-related theta power were similarly affected by stress induction in both sexes, feedback-related beta power depended on the combination of stress induction condition and sex. FRN amplitude and theta power increases were smaller in the stress relative to the control condition in both sexes, demonstrating that acute noise stress impairs performance monitoring irrespective of sex. However, in the stress but not in the control condition, early lower beta-band power increases were larger for men than women, indicating that stress effects on feedback processing are partly sex-dependent. Our findings suggest that sex-specific effects on feedback processing may comprise a factor underlying sex-specific stress responses.

  9. Guest editor - Material exchanges at marine boundaries and surface ocean processes: Forcings and feedbacks

    Digital Repository Service at National Institute of Oceanography (India)

    DileepKumar, M.

    -1 Special section on: Material exchanges at marine boundaries and surface ocean processes: Forcings and feedbacks Preface Exchanges across marine interfaces are important in global material cycles and in the modification of atmospheric composition. Climate... and feedbacks was held during the 2nd Annual Meeting of the Asia?Oceania Geosciences Society (AOGS) in Singapore during 20?24 June 2005. The following Special section contains some of the papers presented at that session. The first article by Sarma addresses...

  10. Punishment sensitivity modulates the processing of negative feedback but not error-induced learning

    Directory of Open Access Journals (Sweden)

    Kerstin eUnger

    2012-06-01

    Full Text Available Accumulating evidence suggests that individual differences in punishment and reward sensitivity are associated with functional alterations in neural systems underlying error and feedback processing. In particular, individuals highly sensitive to punishment have been found to be characterized by larger midfrontal error signals as reflected in the error negativity (Ne/ERN and the FRN (feedback-related negativity. By contrast, reward sensitivity has been shown to relate to the error positivity (Pe. Given that Ne/ERN, FRN, and Pe have been functionally linked to flexible behavioral adaptation, the aim of the present research was to examine how these electrophysiological reflections of error and feedback processing vary as a function of punishment and reward sensitivity during reinforcement learning. We applied a probabilistic learning task that involved three different conditions of feedback validity (100%, 80%, and 50%. In contrast to prior studies using response competition tasks, we did not find reliable correlations between punishment sensitivity and the Ne/ERN. Instead, higher punishment sensitivity predicted larger FRN amplitudes, irrespective of feedback validity. Moreover, higher reward sensitivity was associated with a larger Pe. However, only reward sensitivity was related to better overall learning performance and higher post-error accuracy, whereas highly punishment sensitive participants showed impaired learning performance, suggesting that larger negative feedback-related error signals were not beneficial for learning or even reflected maladaptive information processing in these individuals. Thus, although our findings indicate that individual differences in reward and punishment sensitivity are related to electrophysiological correlates of error and feedback processing, we found less evidence for influences of these personality characteristics on the relation between performance monitoring and feedback-based learning.

  11. Feedback process responsible for intermodel diversity of ENSO variability

    Science.gov (United States)

    An, Soon-Il; Heo, Eun Sook; Kim, Seon Tae

    2017-05-01

    The origin of the intermodel diversity of the El Niño-Southern Oscillation (ENSO) variability is investigated by applying a singular value decomposition (SVD) analysis between the intermodel tropical Pacific sea surface temperature anomalies (SSTA) variance and the intermodel ENSO stability index (BJ index). The first SVD mode features an ENSO-like pattern for the intermodel SSTA variance (74% of total variance) and the dominant thermocline feedback (TH) for the BJ index (51%). Intermodel TH is mainly modified by the intermodel sensitivity of the zonal thermocline gradient response to zonal winds over the equatorial Pacific (βh), and the intermodel βh is correlated higher with the intermodel off-equatorial wind stress curl anomalies than the equatorial zonal wind stress anomalies. Finally, the intermodel off-equatorial wind stress curl is associated with the meridional shape and intensity of ENSO-related wind patterns, which may cause a model-to-model difference in ENSO variability by influencing the off-equatorial oceanic Rossby wave response.

  12. Effects of changes in climate on landscape and regional processes, and feedbacks to the climate system.

    Science.gov (United States)

    Callaghan, Terry V; Björn, Lars Olof; Chernov, Yuri; Chapin, Terry; Christensen, Torben R; Huntley, Brian; Ims, Rolf A; Johansson, Margareta; Jolly, Dyanna; Jonasson, Sven; Matveyeva, Nadya; Panikov, Nicolai; Oechel, Walter; Shaver, Gus; Schaphoff, Sibyll; Sitch, Stephen

    2004-11-01

    Biological and physical processes in the Arctic system operate at various temporal and spatial scales to impact large-scale feedbacks and interactions with the earth system. There are four main potential feedback mechanisms between the impacts of climate change on the Arctic and the global climate system: albedo, greenhouse gas emissions or uptake by ecosystems, greenhouse gas emissions from methane hydrates, and increased freshwater fluxes that could affect the thermohaline circulation. All these feedbacks are controlled to some extent by changes in ecosystem distribution and character and particularly by large-scale movement of vegetation zones. Indications from a few, full annual measurements of CO2 fluxes are that currently the source areas exceed sink areas in geographical distribution. The little available information on CH4 sources indicates that emissions at the landscape level are of great importance for the total greenhouse balance of the circumpolar North. Energy and water balances of Arctic landscapes are also important feedback mechanisms in a changing climate. Increasing density and spatial expansion of vegetation will cause a lowering of the albedo and more energy to be absorbed on the ground. This effect is likely to exceed the negative feedback of increased C sequestration in greater primary productivity resulting from the displacements of areas of polar desert by tundra, and areas of tundra by forest. The degradation of permafrost has complex consequences for trace gas dynamics. In areas of discontinuous permafrost, warming, will lead to a complete loss of the permafrost. Depending on local hydrological conditions this may in turn lead to a wetting or drying of the environment with subsequent implications for greenhouse gas fluxes. Overall, the complex interactions between processes contributing to feedbacks, variability over time and space in these processes, and insufficient data have generated considerable uncertainties in estimating the net

  13. Electrophysiological Correlates of Error Monitoring and Feedback Processing in Second Language Learning.

    Science.gov (United States)

    Bultena, Sybrine; Danielmeier, Claudia; Bekkering, Harold; Lemhöfer, Kristin

    2017-01-01

    Humans monitor their behavior to optimize performance, which presumably relies on stable representations of correct responses. During second language (L2) learning, however, stable representations have yet to be formed while knowledge of the first language (L1) can interfere with learning, which in some cases results in persistent errors. In order to examine how correct L2 representations are stabilized, this study examined performance monitoring in the learning process of second language learners for a feature that conflicts with their first language. Using EEG, we investigated if L2 learners in a feedback-guided word gender assignment task showed signs of error detection in the form of an error-related negativity (ERN) before and after receiving feedback, and how feedback is processed. The results indicated that initially, response-locked negativities for correct (CRN) and incorrect (ERN) responses were of similar size, showing a lack of internal error detection when L2 representations are unstable. As behavioral performance improved following feedback, the ERN became larger than the CRN, pointing to the first signs of successful error detection. Additionally, we observed a second negativity following the ERN/CRN components, the amplitude of which followed a similar pattern as the previous negativities. Feedback-locked data indicated robust FRN and P300 effects in response to negative feedback across different rounds, demonstrating that feedback remained important in order to update memory representations during learning. We thus show that initially, L2 representations may often not be stable enough to warrant successful error monitoring, but can be stabilized through repeated feedback, which means that the brain is able to overcome L1 interference, and can learn to detect errors internally after a short training session. The results contribute a different perspective to the discussion on changes in ERN and FRN components in relation to learning, by extending the

  14. Analysis of Feedback processes in Online Group Interaction: a methodological model

    Directory of Open Access Journals (Sweden)

    Anna Espasa

    2013-06-01

    Full Text Available The aim of this article is to present a methodological model to analyze students' group interaction to improve their essays in online learning environments, based on asynchronous and written communication. In these environments teacher and student scaffolds for discussion are essential to promote interaction. One of these scaffolds can be the feedback. Research on feedback processes has predominantly focused on feedback design rather than on how students utilize feedback to improve learning. This methodological model fills this gap contributing to analyse the implementation of the feedback processes while students discuss collaboratively in a specific case of writing assignments. A review of different methodological models was carried out to define a framework adjusted to the analysis of the relationship of written and asynchronous group interaction, and students' activity and changes incorporated into the final text. The model proposed includes the following dimensions: 1 student participation 2 nature of student learning and 3 quality of student learning. The main contribution of this article is to present the methodological model and also to ascertain the model's operativity regarding how students incorporate such feedback into their essays.

  15. Neural-networks-based feedback linearization versus model predictive control of continuous alcoholic fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Mjalli, F.S.; Al-Asheh, S. [Chemical Engineering Department, Qatar University, Doha (Qatar)

    2005-10-01

    In this work advanced nonlinear neural networks based control system design algorithms are adopted to control a mechanistic model for an ethanol fermentation process. The process model equations for such systems are highly nonlinear. A neural network strategy has been implemented in this work for capturing the dynamics of the mechanistic model for the fermentation process. The neural network achieved has been validated against the mechanistic model. Two neural network based nonlinear control strategies have also been adopted using the model identified. The performance of the feedback linearization technique was compared to neural network model predictive control in terms of stability and set point tracking capabilities. Under servo conditions, the feedback linearization algorithm gave comparable tracking and stability. The feedback linearization controller achieved the control target faster than the model predictive one but with vigorous and sudden controller moves. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  16. The facilitative effects of heart-rate feedback in the emotional processing of claustrophobic fear.

    Science.gov (United States)

    Telch, M J; Valentiner, D P; Ilai, D; Petruzzi, D; Hehmsoth, M

    2000-04-01

    This study examines predictions derived from Foa and Kozak's theory of emotional processing. We hypothesized that the provision of heart-rate feedback would facilitate emotional processing through a fuller activation of the participant's fear structure, and by focusing participants' attention on information that is incompatible with the fear structure, i.e., the interoceptive pattern of habituation. Nonclinical students (N = 54) showing marked claustrophobic fear received 30 min of self-directed exposure to a claustrophobic chamber. Three exposure conditions (heart-rate feedback, paced-tone control, and exposure only control) were examined across six 5-min exposure trials. Participants receiving heart-rate feedback displayed greater between-trial habituation across treatment trials and lower levels of fear at post-treatment. Treatment process findings failed to support the fear activation hypothesis. Implications of the findings for theories of fear reduction are discussed.

  17. Processing expected and unexpected uncertainty is modulated by fearless-dominance personality traits - An exploratory ERP study on feedback processing.

    Science.gov (United States)

    Kogler, Lydia; Sailer, Uta; Derntl, Birgit; Pfabigan, Daniela M

    2017-01-01

    Expectancy and certainty regarding an outcome are important factors during performance monitoring. However, the separate contributions of expected and unexpected uncertainty on different measures of performance monitoring, including feedback-related negativity (FRN) and P300 components, are not well established. The current study investigated their relationship to fearless-dominance, a personality construct described by high social potency and low anxiety. Accurately predicting environmental outcomes in certain and uncertain situations might be a prerequisite of social potency, therefore it may be associated with increased performance monitoring and its ERP correlates. Consequently, expected-uncertain and unexpected-uncertain feedback (by violating previously learned certain and expected feedback) was introduced in addition to expected-certain feedback in healthy individuals during a probabilistic gambling task. In both FRN and P300 components, difference waves were more pronounced for unexpected-uncertain and expected-uncertain compared to expected-certain feedback. Moreover, more fearless-dominant individuals showed diminished feedback processing specifically in expected-uncertain trials, but concurrently enhanced attentional processing in expected-certain trials. These findings indicate adaptive and situation-appropriate utilization of performance monitoring resources in individuals with more pronounced fearless-dominance personality traits. The results indicate that a precise differentiation of expected and unexpected uncertainty in fearless-dominant individuals is mandatory in order to better understand the underlying personality construct and related behavior.

  18. Factors influencing trainers' feedback-giving behavior: a cross-sectional survey

    NARCIS (Netherlands)

    Pelgrim, E.A.M.; Kramer, A.W.M.; Mokkink, H.G.A.; Vleuten, C.P.M. van der

    2014-01-01

    BACKGROUND: The literature provides some insight into the role of feedback givers, but little information about within-trainer factors influencing 'feedback-giving behaviours'. We looked for relationships between characteristics of feedback givers (self-efficacy, task perception, neuroticism, extrav

  19. Market Feedback and Team Commitment in Radical Product Innovation Process

    NARCIS (Netherlands)

    L. Berchicci (Luca); C.L. Tucci (Christopher)

    2008-01-01

    textabstractPrevious research has considered how exploratory market learning processes moderate market and technological uncertainty in radical product development. Scholars argue that new product development (NPD) teams may increase the chances of success of radically new projects by acquiring, ass

  20. Feedback-based error monitoring processes during musical performance: an ERP study.

    Science.gov (United States)

    Katahira, Kentaro; Abla, Dilshat; Masuda, Sayaka; Okanoya, Kazuo

    2008-05-01

    Auditory feedback is important in detecting and correcting errors during sound production when a current performance is compared to an intended performance. In the context of vocal production, a forward model, in which a prediction of action consequence (corollary discharge) is created, has been proposed to explain the dampened activity of the auditory cortex while producing self-generated vocal sounds. However, it is unclear how auditory feedback is processed and what neural mechanism underlies the process during other sound production behavior, such as musical performances. We investigated the neural correlates of human auditory feedback-based error detection using event-related potentials (ERPs) recorded during musical performances. Keyboard players of two different skill levels played simple melodies using a musical score. During the performance, the auditory feedback was occasionally altered. Subjects with early and extensive piano training produced a negative ERP component N210, which was absent in non-trained players. When subjects listened to music that deviated from a corresponding score without playing the piece, N210 did not emerge but the imaginary mismatch negativity (iMMN) did. Therefore, N210 may reflect a process of mismatch between the intended auditory image evoked by motor activity, and actual auditory feedback.

  1. The feedback of massive stars on interstellar astrochemical processes

    CERN Document Server

    De Becker, Michael

    2013-01-01

    Astrochemistry is a discipline that studies physico-chemical processes in astrophysical environments. Such environments are characterized by conditions that are substantially different from those existing in usual chemical laboratories. Models which aim to explain the formation of molecular species in interstellar environments must take into account various factors, including many that are directly, or indirectly related to the populations of massive stars in galaxies. The aim of this paper is to review the influence of massive stars, whatever their evolution stage, on the physico-chemical processes at work in interstellar environments. These influences include the ultraviolet radiation field, the production of high energy particles, the synthesis of radionuclides and the formation of shocks that permeate the interstellar medium.

  2. Proprioceptive deafferentation slows down the processing of visual hand feedback

    DEFF Research Database (Denmark)

    Balslev, Daniela; Miall, R Chris; Cole, Jonathan

    2007-01-01

    During visually guided movements both vision and proprioception inform the brain about the position of the hand, so interaction between these two modalities is presumed. Current theories suggest that this interaction occurs by sensory information from both sources being fused into a more reliable...... proprioception facilitates the processing of visual information during motor control. Subjects used a computer mouse to move a cursor to a screen target. In 28% of the trials, pseudorandomly, the cursor was rotated or the target jumped. Reaction time for the trajectory correction in response to this perturbation...... was compared under conditions with normal and reduced proprioception after 1-Hz rTMS over the hand-contralateral somatosensory cortex. Proprioceptive deafferentation slowed down the reaction time for initiating a motor correction in response to a visual perturbation in hand position, but not to a target jump...

  3. People matter: Perceived sender identity modulates cerebral processing of socio-emotional language feedback.

    Science.gov (United States)

    Schindler, Sebastian; Kissler, Johanna

    2016-07-01

    How do human brains integrate content with social context in communication? Recent research demonstrates that the perceived communicative embedding of perceptually identical language messages alters their cortical processing. When emotional trait-adjectives are perceived as human-generated personality feedback, event-related brain potentials are considerably larger than when the same adjectives are perceived as random computer-generated feedback. Here, we investigate the unique role of ascribed sender humanness for the underlying neural mechanisms. Participants were told that they were going to receive written positive, negative, or neutral feedback from an unknown stranger or from a socially intelligent computer system while high-density EEG was recorded. In the event-related potential (ERP), feedback from the 'human sender' elicited larger P2, Early Posterior Negativity (EPN), P3, and Late Positive Potential (LPP) components. The sources of this activity were localized in extended visual cortex, but also in the right superior frontal gyri, related to mentalizing about others, and the bilateral postcentral gyri implicated in embodied language processing. For emotional feedback, larger EPN, P3 and LPP amplitudes were also observed, resulting from enhanced activity in visual and temporal regions. Finally, for the EPN an interaction between sender and emotion was found, showing substantially increased visual processing of human-generated emotional feedback. These data confirm visual amplification effects induced by motivated attention but crucially also reveal distinct effects of perceiving a communication partner as human that activate 'social brain' structures. Obviously who is perceived as saying something can be as relevant as what is said and induce specific brain activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Dynamic Feedbacks Between Flow, Erosion and Evolving River Bank Roughness Revealed Through Repeat High-Resolution Topographic Surveys

    Science.gov (United States)

    Leyland, J.; Darby, S. E.; Rinaldi, M.; Teruggi, L. B.; Ostuni, D.

    2012-12-01

    Bank erosion is a key process in fluvial dynamics, with significant fractions of the total sediment load being sourced from river banks. Studies have shown that hydraulic erosion of the bank toe is a driving factor of long term rates of bank retreat. Fluvial bank erosion rates are often quantified using an excess shear stress model where the erosion rate is a function of the boundary shear stress applied by the flow above a critical threshold. Research has shown that the form roughness induced by natural topographic bank features such as slumps, spurs and embayments, is a major component of the spatially-averaged total shear stress. The skin friction component of this shear stress is typically an order of magnitude less than the total, meaning that the form roughness provides an important control on bank erosion rates. However, measuring the relative components of the total shear stress for a natural system is not straightforward. In this research we apply the method of Kean and Smith [2006, J. Geophys. Res., 111(4), F04009, doi:10.1029/2006JF000467] to partition the form and skin drag components of river bank roughness for an eroding bank of the Cecina River in central Italy. This method approximates the form drag component of the roughness along a longitudinal bank profile as a series of user defined Gaussian curves, with the skin friction component estimated through analysis of the deviations of the data from the fitted curves. For our site, a temporal sequence (2003 - 2011) of high-resolution topographic surveys has been collected through a combination of photogrammetry and Terrestrial Laser Scanning. For each survey five vertically equidistant profiles are extracted and analysed alongside DEMs of difference and associated flow data modelled using the distributed hydrological model MOBIDIC. The data are used to explore the dynamic feedbacks that exist between river discharge, bank erosion processes and bank form roughness, revealing insights into the self

  5. Stimulus-Outcome Learnability Differentially Activates Anterior Cingulate and Hippocampus at Feedback Processing

    Science.gov (United States)

    Rodriguez, Paul F.

    2009-01-01

    Memory systems are known to be influenced by feedback and error processing, but it is not well known what aspects of outcome contingencies are related to different memory systems. Here we use the Rescorla-Wagner model to estimate prediction errors in an fMRI study of stimulus-outcome association learning. The conditional probabilities of outcomes…

  6. Approaching Error-Free Customer Satisfaction through Process Change and Feedback Systems

    Science.gov (United States)

    Berglund, Kristin M.; Ludwig, Timothy D.

    2009-01-01

    Employee-based errors result in quality defects that can often impact customer satisfaction. This study examined the effects of a process change and feedback system intervention on error rates of 3 teams of retail furniture distribution warehouse workers. Archival records of error codes were analyzed and aggregated as the measure of quality. The…

  7. Relations between scripted online peer feedback processes and quality of written argumentative essay

    NARCIS (Netherlands)

    Noroozi, Omid; Biemans, Harm; Mulder, Martin

    2016-01-01

    Teachers often complain about the quality of students' written essays in higher education. This study explores the relations between scripted online peer feedback processes and quality of written argumentative essay as they occur in an authentic learning situation with direct practical relevance.

  8. Approaching Error-Free Customer Satisfaction through Process Change and Feedback Systems

    Science.gov (United States)

    Berglund, Kristin M.; Ludwig, Timothy D.

    2009-01-01

    Employee-based errors result in quality defects that can often impact customer satisfaction. This study examined the effects of a process change and feedback system intervention on error rates of 3 teams of retail furniture distribution warehouse workers. Archival records of error codes were analyzed and aggregated as the measure of quality. The…

  9. A key region in the human parietal cortex for processing proprioceptive hand feedback during reaching movements.

    Science.gov (United States)

    Reichenbach, Alexandra; Thielscher, Axel; Peer, Angelika; Bülthoff, Heinrich H; Bresciani, Jean-Pierre

    2014-01-01

    Seemingly effortless, we adjust our movements to continuously changing environments. After initiation of a goal-directed movement, the motor command is under constant control of sensory feedback loops. The main sensory signals contributing to movement control are vision and proprioception. Recent neuroimaging studies have focused mainly on identifying the parts of the posterior parietal cortex (PPC) that contribute to visually guided movements. We used event-related TMS and force perturbations of the reaching hand to test whether the same sub-regions of the left PPC contribute to the processing of proprioceptive-only and of multi-sensory information about hand position when reaching for a visual target. TMS over two distinct stimulation sites elicited differential effects: TMS applied over the posterior part of the medial intraparietal sulcus (mIPS) compromised reaching accuracy when proprioception was the only sensory information available for correcting the reaching error. When visual feedback of the hand was available, TMS over the anterior intraparietal sulcus (aIPS) prolonged reaching time. Our results show for the first time the causal involvement of the posterior mIPS in processing proprioceptive feedback for online reaching control, and demonstrate that distinct cortical areas process proprioceptive-only and multi-sensory information for fast feedback corrections.

  10. A statistical analysis of the Two Dimensional XMM-Newton Group Survey: The impact of feedback on group properties

    CERN Document Server

    Johnson, Ria; Finoguenov, Alexis

    2009-01-01

    (abridged) We present a statistical analysis of 28 nearby galaxy groups from the Two-Dimensional XMM-Newton Group Survey (2dXGS). We focus on entropy and the role of feedback, dividing the sample into cool core (CC) and non cool core (NCC) systems, the first time the latter have been studied in detail in the group regime. The coolest groups have steeper entropy profiles than the warmest systems, and NCC groups have higher central entropy and exhibit more scatter than their CC counterparts. We compare the entropy distribution of the gas in each system to the expected theoretical distribution ignoring non-gravitational processes. In all cases, the observed maximum entropy far exceeds that expected theoretically, and simple models for modifications of the theoretical entropy distribution perform poorly. Applying initial pre-heating, followed by radiative cooling, generally fails to match the low entropy behaviour, and only performs well when the difference between the maximum entropy of the observed and theoreti...

  11. Variables that affect the process and outcome of feedback, relevant for medical training: a meta-review.

    Science.gov (United States)

    van de Ridder, J M Monica; McGaghie, William C; Stokking, Karel M; ten Cate, Olle T J

    2015-07-01

    Feedback is considered important in medical education. The literature is not clear about the mechanisms that contribute to its effects, which are often small to moderate and at times contradictory. A variety of variables seem to influence the impact of feedback on learning. The aim of this study was to determine which variables influence the process and outcomes of feedback in settings relevant to medical education. A myriad of studies on feedback have been conducted. To determine the most researched variables, we limited our review to meta-analyses and literature reviews published in the period from January 1986 to February 2012. According to our protocol, we first identified features of the feedback process that influence its effects and subsequently variables that influence these features. We used a chronological model of the feedback process to categorise all variables found. A systematic search of ERIC, PsycINFO and MEDLINE yielded 1101 publications, which we reduced to 203, rejecting papers on six exclusion criteria. Of these, 46 met the inclusion criteria. In our four-phase model, we identified 33 variables linked to task performance (e.g. task complexity, task nature) and feedback reception (e.g. self-esteem, goal-setting behaviour) by trainees, and to observation (e.g. focus, intensity) and feedback provision (e.g. form, content) by supervisors that influence the subsequent effects of the feedback process. Variables from all phases influence the feedback process and effects, but variables that influence the quality of the observation and rating of the performance dominate the literature. There is a paucity of studies addressing other, seemingly relevant variables. The larger picture of variables that influence the process and outcome of feedback, relevant for medical education, shows many open spaces. We suggest that targeted studies be carried out to expand our knowledge of these important aspects of feedback in medical education. © 2015 John Wiley

  12. Selective and divided attention modulates auditory-vocal integration in the processing of pitch feedback errors.

    Science.gov (United States)

    Liu, Ying; Hu, Huijing; Jones, Jeffery A; Guo, Zhiqiang; Li, Weifeng; Chen, Xi; Liu, Peng; Liu, Hanjun

    2015-08-01

    Speakers rapidly adjust their ongoing vocal productions to compensate for errors they hear in their auditory feedback. It is currently unclear what role attention plays in these vocal compensations. This event-related potential (ERP) study examined the influence of selective and divided attention on the vocal and cortical responses to pitch errors heard in auditory feedback regarding ongoing vocalisations. During the production of a sustained vowel, participants briefly heard their vocal pitch shifted up two semitones while they actively attended to auditory or visual events (selective attention), or both auditory and visual events (divided attention), or were not told to attend to either modality (control condition). The behavioral results showed that attending to the pitch perturbations elicited larger vocal compensations than attending to the visual stimuli. Moreover, ERPs were likewise sensitive to the attentional manipulations: P2 responses to pitch perturbations were larger when participants attended to the auditory stimuli compared to when they attended to the visual stimuli, and compared to when they were not explicitly told to attend to either the visual or auditory stimuli. By contrast, dividing attention between the auditory and visual modalities caused suppressed P2 responses relative to all the other conditions and caused enhanced N1 responses relative to the control condition. These findings provide strong evidence for the influence of attention on the mechanisms underlying the auditory-vocal integration in the processing of pitch feedback errors. In addition, selective attention and divided attention appear to modulate the neurobehavioral processing of pitch feedback errors in different ways.

  13. Neural Dynamics of Feedforward and Feedback Processing in Figure-Ground Segregation

    Directory of Open Access Journals (Sweden)

    Oliver W. Layton

    2014-09-01

    Full Text Available Determining whether a region belongs to the interior or exterior of a shape (figure-ground segregation is a core competency of the primate brain, yet the underlying mechanisms are not well understood. Many models assume that figure-ground segregation occurs by assembling progressively more complex representations through feedforward connections, with feedback playing only a modulatory role. We present a dynamical model of figure-ground segregation in the primate ventral stream wherein feedback plays a crucial role in disambiguating a figure’s interior and exterior. We introduce a processing strategy whereby jitter in RF center locations and variation in RF sizes is exploited to enhance and suppress neural activity inside and outside of figures, respectively. Feedforward projections emanate from units that model cells in V4 known to respond to the curvature of boundary contours (curved contour cells, and feedback projections from units predicted to exist in IT that strategically group neurons with different RF sizes and RF center locations (teardrop cells. Neurons (convex cells that preferentially respond when centered on a figure dynamically balance feedforward (bottom-up information and feedback from higher visual areas. The activation is enhanced when an interior portion of a figure is in the RF via feedback from units that detect closure in the boundary contours of a figure. Our model produces maximal activity along the medial axis of well-known figures with and without concavities, and inside algorithmically generated shapes. Our results suggest that the dynamic balancing of feedforward signals with the specific feedback mechanisms proposed by the model is crucial for figure-ground segregation.

  14. Structuring the Peer Assessment Process: A Multilevel Approach for the Impact on Product Improvement and Peer Feedback Quality

    Science.gov (United States)

    Gielen, M.; De Wever, B.

    2015-01-01

    In order to optimize students' peer feedback processes, this study investigates how an instructional intervention in the peer assessment process can have a beneficial effect on students' performance in a wiki environment in first-year higher education. The main aim was to study the effect of integrating a peer feedback template with a varying…

  15. Exploring cultural differences in feedback processes and perceived instructiveness during clerkships : Replicating a Dutch study in Indonesia

    NARCIS (Netherlands)

    Suhoyo, Yoyo; van Hell, Elisabeth A.; Prihatiningsih, Titi S.; Kuks, Jan B. M.; Cohen-Schotanus, Janke

    2014-01-01

    Context: Cultural differences between countries may entail differences in feedback processes. Aims: By replicating a Dutch study in Indonesia, we analysed whether differences in processes influenced the perceived instructiveness of feedback. Methods: Over a two-week period, Indonesian students (n =

  16. Structuring the Peer Assessment Process: A Multilevel Approach for the Impact on Product Improvement and Peer Feedback Quality

    Science.gov (United States)

    Gielen, M.; De Wever, B.

    2015-01-01

    In order to optimize students' peer feedback processes, this study investigates how an instructional intervention in the peer assessment process can have a beneficial effect on students' performance in a wiki environment in first-year higher education. The main aim was to study the effect of integrating a peer feedback template with a varying…

  17. Constructing wetlands: measuring and modeling feedbacks of oxidation processes between plants and clay-rich material

    Science.gov (United States)

    Saaltink, Rémon; Dekker, Stefan C.; Griffioen, Jasper; Wassen, Martin J.

    2016-04-01

    Interest is growing in using soft sediment as a building material in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here the option of dredging some of the clay-rich lake-bed sediment and using it to construct 10.000 ha of wetland will soon go under construction. Natural processes will be utilized during and after construction to accelerate ecosystem development. Knowing that plants can eco-engineer their environment via positive or negative biogeochemical plant-soil feedbacks, we conducted a six-month greenhouse experiment to identify the key biogeochemical processes in the mud when Phragmites australis is used as an eco-engineering species. We applied inverse biogeochemical modeling to link observed changes in pore water composition to biogeochemical processes. Two months after transplantation we observed reduced plant growth and shriveling as well as yellowing of foliage. The N:P ratios of plant tissue were low and were affected not by hampered uptake of N but by enhanced uptake of P. Plant analyses revealed high Fe concentrations in the leaves and roots. Sulfate concentrations rose drastically in our experiment due to pyrite oxidation; as reduction of sulfate will decouple Fe-P in reducing conditions, we argue that plant-induced iron toxicity hampered plant growth, forming a negative feedback loop, while simultaneously there was a positive feedback loop, as iron toxicity promotes P mobilization as a result of reduced conditions through root death, thereby stimulating plant growth and regeneration. Given these two feedback mechanisms, we propose that when building wetlands from these mud deposits Fe-tolerant species are used rather than species that thrive in N-limited conditions. The results presented in this study demonstrate the importance of studying the biogeochemical properties of the building material and the feedback mechanisms between plant and soil prior to finalizing the design of the eco-engineering project.

  18. O feedback e sua importância no processo de tutoria a distância Feedback and its importance to the distance education tutoring process

    Directory of Open Access Journals (Sweden)

    Denise Martins de Abreu-e-Lima

    2011-08-01

    Full Text Available Considerando o crescimento da Educação a Distância no contexto brasileiro; o ingresso de um novo profissional da educação - o tutor - na equipe pedagógica; e a importância de sua interação com os alunos, este artigo tem como objetivos revisar algumas definições de feedback encontradas na literatura, descrever os modelos de feedback adotados nos cursos de EaD ministrados em uma universidade federal brasileira, apresentar as orientações dadas nos cursos de formação de tutores realizados pela instituição e discutir o papel da linguagem nos processos de feedback. De acordo com a discussão feita, são apontadas as principais diretrizes para a utilização de feedback em ambientes virtuais.Taking into consideration the growth of Distance Education field in the Brazilian educational context, the new roles of teaching such as the tutor in the teaching team, this paper aims to review some definitions of feedback found in current literature as well as to point out the models of feedback adopted at Distance Education programs offered by a Brazilian Federal University. It also aims to present the guidelines given to online tutors engaged in the courses offered by these institutional programs and to discuss the role of language in the feedback process. According with the present discussion, some guidelines to the use of feedback in online environment are given.

  19. Expectancy Effects in Feedback Processing are Explained Primarily by Time-frequency Delta not Theta.

    Science.gov (United States)

    Watt, Adreanna T M; Bachman, Matthew D; Bernat, Edward M

    2017-08-30

    The roles of outcome valence and expectancy in feedback processing have been investigated as important factors modulating event-related potential (ERP) measures including the feedback negativity (FN) and P300, but results have been inconsistent. Recent work from our group has shown that processes underlying the FN and P300 are better represented as separable processes in the theta (3-7Hz) and delta (0-3Hz) ranges using time-frequency analysis. The current study evaluated the modulation of time-domain FN and P300 and time-frequency theta and delta to outcome valence and expectancy in a gambling feedback task paradigm.Results revealed that the FN was sensitive to valence but not expectancy, and that valence effects were driven by loss-sensitive theta and gain-sensitive delta. Alternatively, the P300 was sensitive to the expectedness of outcomes but only for gain trials, and these expectancy differences were explained by time-frequency delta not theta. These results add to a growing body of research showing that time-frequency measures reflect separable processes underlying time-domain components, where theta is more sensitive to primary task features and less sensitive to secondary features while delta is sensitive to primary and more complex, secondary task features. Copyright © 2017. Published by Elsevier B.V.

  20. Evaluating a Web-Based Health Risk Assessment With Tailored Feedback: What Does an Expert Focus Group Yield Compared to a Web-Based End-User Survey?

    Science.gov (United States)

    Vosbergen, Sandra; Mahieu, Guy R; Laan, Eva K; Kraaijenhagen, Roderik A; Jaspers, Monique WM

    2014-01-01

    Background Increasingly, Web-based health applications are developed for the prevention and management of chronic diseases. However, their reach and utilization is often disappointing. Qualitative evaluations post-implementation can be used to inform the optimization process and ultimately enhance their adoption. In current practice, such evaluations are mainly performed with end-user surveys. However, a review approach by experts in a focus group may be easier to administer and might provide similar results. Objective The aim of this study was to assess whether industrial design engineers in a focus group would address the same issues as end users in a Web-based survey when evaluating a commercial Web-based health risk assessment (HRA) with tailored feedback. Methods Seven Dutch companies used the HRA as part of their corporate health management strategy. Employees using the HRA (N=2289) and 10 independent industrial designers were invited to participate in the study. The HRA consisted of four components: (1) an electronic health questionnaire, (2) biometric measurements, (3) laboratory evaluation, and (4) individually tailored feedback generated by decision support software. After participating in the HRA as end users, both end users and designers evaluated the program. End users completed an evaluation questionnaire that included a free-text field. Designers participated in a focus group discussion. Constructs from user satisfaction and technology acceptance theories were used to categorize and compare the remarks from both evaluations. Results We assessed and qualitatively analyzed 294 remarks of 189 end users and 337 remarks of 6 industrial designers, pertaining to 295 issues in total. Of those, 137 issues were addressed in the end-user survey and 148 issues in the designer focus group. Only 7.3% (10/137) of the issues addressed in the survey were also addressed in the focus group. End users made more remarks about the usefulness of the HRA and prior

  1. How baryonic feedback processes can affect dark matter halos: a stochastic model

    Science.gov (United States)

    Freundlich, J.; El-Zant, A.; Combes, F.

    2016-12-01

    Feedback processes from stars and active galactic nuclei result in gas density fluctuations which can contribute to `heating' dark matter haloes, decrease their density at the center and hence form more realistic `cores' than the steep `cusps' predicted by cold dark matter (CDM) simulations. We present a theoretical model deriving this effect from first principles: stochastic density variations in the gas distribution perturb the gravitational potential and hence affect the halo particles. We analytically derive the velocity dispersion imparted to the CDM particles and the corresponding relaxation time, and further perform numerical simulations to show that the assumed process can indeed lead to the formation of a core in an initially cuspy halo within a timescale comparable to the derived relaxation time. This suggests that feedback-induced cusp-core transformations observed in hydrodynamic simulations of galaxy formation may be understood and parametrized in relatively simple terms.

  2. Feedback correction of injection errors using digital signal-processing techniques

    Directory of Open Access Journals (Sweden)

    N. S. Sereno

    2007-01-01

    Full Text Available Efficient transfer of electron beams from one accelerator to another is important for 3rd-generation light sources that operate using top-up. In top-up mode, a constant amount of charge is injected at regular intervals into the storage ring to replenish beam lost primarily due to Touschek scattering. Top-up therefore requires that the complex of injector accelerators that fill the storage ring transport beam with a minimum amount of loss. Injection can be a source of significant beam loss if not carefully controlled. In this note we describe a method of processing injection transient signals produced by beam-position monitors and using the processed data in feedback. Feedback control using the technique described here has been incorporated in the Advanced Photon Source (APS booster synchrotron to correct injection transients.

  3. Feedback correction of injection errors using digital signal-processing techniques

    Science.gov (United States)

    Sereno, N. S.; Lenkszus, F. R.

    2007-01-01

    Efficient transfer of electron beams from one accelerator to another is important for 3rd-generation light sources that operate using top-up. In top-up mode, a constant amount of charge is injected at regular intervals into the storage ring to replenish beam lost primarily due to Touschek scattering. Top-up therefore requires that the complex of injector accelerators that fill the storage ring transport beam with a minimum amount of loss. Injection can be a source of significant beam loss if not carefully controlled. In this note we describe a method of processing injection transient signals produced by beam-position monitors and using the processed data in feedback. Feedback control using the technique described here has been incorporated in the Advanced Photon Source (APS) booster synchrotron to correct injection transients.

  4. A model of motion transparency processing with local center-surround interactions and feedback.

    Science.gov (United States)

    Raudies, Florian; Mingolla, Ennio; Neumann, Heiko

    2011-11-01

    Motion transparency occurs when multiple coherent motions are perceived in one spatial location. Imagine, for instance, looking out of the window of a bus on a bright day, where the world outside the window is passing by and movements of passengers inside the bus are reflected in the window. The overlay of both motions at the window leads to motion transparency, which is challenging to process. Noisy and ambiguous motion signals can be reduced using a competition mechanism for all encoded motions in one spatial location. Such a competition, however, leads to the suppression of multiple peak responses that encode different motions, as only the strongest response tends to survive. As a solution, we suggest a local center-surround competition for population-encoded motion directions and speeds. Similar motions are supported, and dissimilar ones are separated, by representing them as multiple activations, which occurs in the case of motion transparency. Psychophysical findings, such as motion attraction and repulsion for motion transparency displays, can be explained by this local competition. Besides this local competition mechanism, we show that feedback signals improve the processing of motion transparency. A discrimination task for transparent versus opaque motion is simulated, where motion transparency is generated by superimposing large field motion patterns of either varying size or varying coherence of motion. The model's perceptual thresholds with and without feedback are calculated. We demonstrate that initially weak peak responses can be enhanced and stabilized through modulatory feedback signals from higher stages of processing.

  5. On the state dependency of fast feedback processes in (palaeo) climate sensitivity

    CERN Document Server

    von der Heydt, Anna S; van de Wal, Roderik S W; Dijkstra, Henk A

    2014-01-01

    The equilibrium (Charney) climate sensitivity is the equilibrium change in Earth's global mean surface temperature due to a radiative forcing associated with a doubling of the atmospheric CO$_2$ concentration. Palaeo data have been frequently used to determine this value, and - if slow feedback processes (e.g. land-ice albedo) are adequately taken into account - they indicate a similar range as estimates based on climate model results. In most studies it is implicitly assumed that the (fast) feedback processes are independent of the background climate state, e.g., are equally strong during warm and cold periods. Here we assess the dependency of the fast feedback processes on the background climate state using data of the last 800 kyr and a conceptual climate model for interpretation. By applying a new method which explicitly considers the background climate state we calculate a specific climate sensitivity of 0.59-1.15 K(Wm$^{-2}$)$^{-1}$ corresponding to a warming of 2.2 to 4.3 K for a CO$_2$ doubling at a 6...

  6. The results of a survey highlighting issues with feedback on medical training in the United Kingdom and how a Smartphone App could provide a solution.

    Science.gov (United States)

    Gray, Thomas G; Hood, Gill; Farrell, Tom

    2015-11-06

    Feedback drives learning in medical education. Healthcare Supervision Logbook (HSL) is a Smartphone App developed at Sheffield Teaching Hospitals for providing feedback on medical training, from both a trainee's and a supervisor's perspective. In order to establish a mandate for the role of HSL in clinical practice, a large survey was carried out. Two surveys (one for doctors undertaking specialty training and a second for consultants supervising their training) were designed. The survey for doctors-in-training was distributed to all specialty trainees in the South and West localities of the Health Education Yorkshire and the Humber UK region. The survey for supervisors was distributed to all consultants involved in educational and clinical supervision of specialty trainees at Sheffield Teaching Hospitals. The results confirm that specialty trainees provide feedback on their training infrequently-66 % do so only annually. 96 % of the specialty trainees owned a Smartphone and 45 % said that they would be willing to use a Smartphone App to provide daily feedback on the clinical and educational supervision they receive. Consultant supervisors do not receive regular feedback on the educational and clinical supervision they provide to trainees-56 % said they never received such feedback and 33 % said it was only on an annual basis. 86 % of consultants surveyed owned a Smartphone and 41 % said they would be willing to use a Smartphone App to provide feedback on the performance of trainees they were supervising. Feedback on medical training is recorded by specialty trainees infrequently and consultants providing educational and clinical supervision often do not receive any feedback on their performance in this area. HSL is a simple, quick and efficient way to collect and collate feedback on medical training to improve this situation. Good support and education needs to be provided when implementing this new technology.

  7. Essential processes for cognitive behavioral clinical supervision: Agenda setting, problem-solving, and formative feedback.

    Science.gov (United States)

    Cummings, Jorden A; Ballantyne, Elena C; Scallion, Laura M

    2015-06-01

    Clinical supervision should be a proactive and considered endeavor, not a reactive one. To that end, supervisors should choose supervision processes that are driven by theory, best available research, and clinical experience. These processes should be aimed at helping trainees develop as clinicians. We highlight 3 supervision processes we believe should be used at each supervision meeting: agenda setting, encouraging trainee problem-solving, and formative feedback. Although these are primarily cognitive-behavioral skills, they can be helpful in combination with other supervision models. We provide example dialogue from supervision exchanges, and discuss theoretical and research support for these processes. Using these processes not only encourages trainee development but also models for them how to use the same processes and approaches with clients.

  8. Social provocation modulates decision making and feedback processing: Examining the trajectory of development in adolescent participants

    Directory of Open Access Journals (Sweden)

    Hannah L. Pincham

    2015-10-01

    Full Text Available Increasingly, research is turning to the ways in which social context impacts decision making and feedback processing in adolescents. The current study recorded electroencephalography to examine the trajectory of development across adolescence, with a focus on how social context impacts cognition and behaviour. To that end, younger (10–12 years and older (14–16 years adolescents played a modified Taylor Aggression Paradigm against two virtual opponents: a low-provoker and a high-provoker. During the task's decision phase (where participants select punishment for their opponent, we examined two event-related potentials: the N2 and the late positive potential (LPP. During the outcome phase (where participants experience win or loss feedback, we measured the feedback related negativity (FRN. Although N2 amplitudes did not vary with provocation, LPP amplitudes were enhanced under high provocation for the younger group, suggesting that emotional reactivity during the decision phase was heightened for early adolescents. During the outcome phase, the FRN was reduced following win outcomes under high provocation for both groups, suggesting that a highly provocative social opponent may influence the reward response. Collectively, the data argue that social context is an important factor modulating neural responses in adolescent behavioural and brain development.

  9. Fast photonic information processing using semiconductor lasers with delayed optical feedback: role of phase dynamics.

    Science.gov (United States)

    Nguimdo, Romain Modeste; Verschaffelt, Guy; Danckaert, Jan; Van der Sande, Guy

    2014-04-01

    Semiconductor lasers subject to delayed optical feedback have recently shown great potential in solving computationally hard tasks. By optically implementing a neuro-inspired computational scheme, called reservoir computing, based on the transient response to optical data injection, high processing speeds have been demonstrated. While previous efforts have focused on signal bandwidths limited by the semiconductor laser's relaxation oscillation frequency, we demonstrate numerically that the much faster phase response makes significantly higher processing speeds attainable. Moreover, this also leads to shorter external cavity lengths facilitating future on-chip implementations. We numerically benchmark our system on a chaotic time-series prediction task considering two different feedback configurations. The results show that a prediction error below 4% can be obtained when the data is processed at 0.25 GSamples/s. In addition, our insight into the phase dynamics of optical injection in a semiconductor laser also provides a clear understanding of the system performance at different pump current levels, even below solitary laser threshold. Considering spontaneous emission noise and noise in the readout layer, we obtain good prediction performance at fast processing speeds for realistic values of the noise strength.

  10. Long-term coupling and feedbacks between surface processes and tectonics during rifting

    Science.gov (United States)

    Theunissen, T.; Huismans, R. S.

    2015-12-01

    Whereas significant efforts have been made to understand the relationship between mountain building and surfaces processes, limited research has been done on the relationship between surface processes and extensional tectonics. Here we present high-resolution 2-D coupled tectonic-surface processes modeling of extensional basin formation. The main aim is to find out how erosion and deposition affect the deformation in extensional systems. We test sensitivity of the rift mode to the combined effects of crustal rheology and varying surface process efficiency (erodibility, sea level). The results show that both erosion of rift flank areas and basin deposition enhance localization of crustal deformation. Frictional-plastic extensional shear zones accumulate more deformation during a longer period of time, and time of lithospheric rupture is delayed when fluvial erosion, transport and deposition are efficient. We show that removal of mass from rift flanks and sedimentary loading in the basin area are the main cause of the feedbacks providing a first order control on the style of extensional basin formation. Variation of strain localization in natural rift systems correlates with the observed behavior and suggests similar feedbacks as demonstrated by the forward numerical models.

  11. Reconfigurable Optical Signal Processing Based on a Distributed Feedback Semiconductor Optical Amplifier.

    Science.gov (United States)

    Li, Ming; Deng, Ye; Tang, Jian; Sun, Shuqian; Yao, Jianping; Azaña, José; Zhu, Ninghua

    2016-01-27

    All-optical signal processing has been considered a solution to overcome the bandwidth and speed limitations imposed by conventional electronic-based systems. Over the last few years, an impressive range of all-optical signal processors have been proposed, but few of them come with reconfigurability, a feature highly needed for practical signal processing applications. Here we propose and experimentally demonstrate an analog optical signal processor based on a phase-shifted distributed feedback semiconductor optical amplifier (DFB-SOA) and an optical filter. The proposed analog optical signal processor can be reconfigured to perform signal processing functions including ordinary differential equation solving and temporal intensity differentiation. The reconfigurability is achieved by controlling the injection currents. Our demonstration provitdes a simple and effective solution for all-optical signal processing and computing.

  12. Reconfigurable Optical Signal Processing Based on a Distributed Feedback Semiconductor Optical Amplifier

    Science.gov (United States)

    Li, Ming; Deng, Ye; Tang, Jian; Sun, Shuqian; Yao, Jianping; Azaña, José; Zhu, Ninghua

    2016-01-01

    All-optical signal processing has been considered a solution to overcome the bandwidth and speed limitations imposed by conventional electronic-based systems. Over the last few years, an impressive range of all-optical signal processors have been proposed, but few of them come with reconfigurability, a feature highly needed for practical signal processing applications. Here we propose and experimentally demonstrate an analog optical signal processor based on a phase-shifted distributed feedback semiconductor optical amplifier (DFB-SOA) and an optical filter. The proposed analog optical signal processor can be reconfigured to perform signal processing functions including ordinary differential equation solving and temporal intensity differentiation. The reconfigurability is achieved by controlling the injection currents. Our demonstration provitdes a simple and effective solution for all-optical signal processing and computing.

  13. Modeling the feedback between aerosol and boundary layer processes: a case study in Beijing, China.

    Science.gov (United States)

    Miao, Yucong; Liu, Shuhua; Zheng, Yijia; Wang, Shu

    2016-02-01

    Rapid development has led to frequent haze in Beijing. With mountains and sea surrounding Beijing, the pollution is found to be influenced by the mountain-plain breeze and sea-land breeze in complex ways. Meanwhile, the presence of aerosols may affect the surface energy balance and impact these boundary layer (BL) processes. The effects of BL processes on aerosol pollution and the feedback between aerosol and BL processes are not yet clearly understood. Thus, the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) is used to investigate the possible effects and feedbacks during a haze episode on 23 September 2011. Influenced by the onshore prevailing wind, sea-breeze, and upslope breeze, about 45% of surface particulate matter (PM)2.5 in Beijing are found to be contributed by its neighbor cities through regional transport. In the afternoon, the development of upslope breeze suppresses the growth of BL in Beijing by imposing a relatively low thermal stable layer above the BL, which exacerbates the pollution. Two kinds of feedback during the daytime are revealed as follows: (1) as the aerosols absorb and scatter the solar radiation, the surface net radiation and sensible heat flux are decreased, while BL temperature is increased, resulting in a more stable and shallower BL, which leads to a higher surface PM2.5 concentration in the morning and (2) in the afternoon, as the presence of aerosols increases the BL temperature over plains, the upslope breeze is weakened, and the boundary layer height (BLH) over Beijing is heightened, resulting in the decrease of the surface PM2.5 concentration there.

  14. Multiple DSP system for real time parallel processing and feedback control on fusion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, A.P.; Correia, C.M.B.; Varandas, C.A.F. [Associacao EURATOM, Lisboa (Portugal). Nucl. Inst. Superior Tecnico; Schneider, F. [Association EURATOM/IPP, Max-Planck-Institut fuer Plasmaphysik, D-85748 Garching (Germany)

    1999-01-01

    This paper describes a specially designed system for real time parallel processing and feedback control on fusion experiments. The system is being implemented in PCI and VME modules, based on an array of four synchronizable DSPs, with 1 Mbyte of global RAM, 12 bits resolution, four analog inputs with sampling frequency up to 40 MSPS, two analog or waveform generator outputs with an update rate up to 100 MSPS, eight digital opto-coupled inputs/outputs and one external global trigger optical input. The user interface appears as a virtual instrument from LabView for Windows. (orig.) 7 refs.

  15. Feedback control of the vacuum-assisted resin transfer molding (VARTM) process

    Science.gov (United States)

    Heider, Dirk; Graf, A.; Fink, Bruce K.; Gillespie, John W., Jr.

    1999-02-01

    The Vacuum Assisted Resin Transfer Molding (VARTM) technique is a liquid-molding process that offers the potential to significantly reduce fabrication costs for large-scale composite structures. The VARTM workcell is used to evaluate control strategies and sensors such as SMARTweave to provide feedback for an intelligent control system. Current VARTM systems lack automated control systems resulting in part to part variability. This research presents a continuously controlled vacuum actuator system and the influence of vacuum gradients on resin flow front control.

  16. The Feedback Process: Perspectives of First and Second Year Undergraduate Students in the Disciplines of Education, Health Science and Nursing

    Science.gov (United States)

    Douglas, Tracy; Salter, Susan; Iglesias, Miguel; Dowlman, Michele; Eri, Raj

    2016-01-01

    The purpose of this study was to determine the current perspectives of feedback from first and second year undergraduate students enrolled in blended units of study which incorporated both face-to-face and online components. Students enrolled in a unit of study taught by the School of Health Sciences at the University of Tasmania were surveyed to…

  17. A New Feedback-Based Method for Parameter Adaptation in Image Processing Routines.

    Science.gov (United States)

    Khan, Arif Ul Maula; Mikut, Ralf; Reischl, Markus

    2016-01-01

    The parametrization of automatic image processing routines is time-consuming if a lot of image processing parameters are involved. An expert can tune parameters sequentially to get desired results. This may not be productive for applications with difficult image analysis tasks, e.g. when high noise and shading levels in an image are present or images vary in their characteristics due to different acquisition conditions. Parameters are required to be tuned simultaneously. We propose a framework to improve standard image segmentation methods by using feedback-based automatic parameter adaptation. Moreover, we compare algorithms by implementing them in a feedforward fashion and then adapting their parameters. This comparison is proposed to be evaluated by a benchmark data set that contains challenging image distortions in an increasing fashion. This promptly enables us to compare different standard image segmentation algorithms in a feedback vs. feedforward implementation by evaluating their segmentation quality and robustness. We also propose an efficient way of performing automatic image analysis when only abstract ground truth is present. Such a framework evaluates robustness of different image processing pipelines using a graded data set. This is useful for both end-users and experts.

  18. A Big Data and Learning Analytics Approach to Process-Level Feedback in Cognitive Simulations.

    Science.gov (United States)

    Pecaric, Martin; Boutis, Kathy; Beckstead, Jason; Pusic, Martin

    2017-02-01

    Collecting and analyzing large amounts of process data for the purposes of education can be considered a big data/learning analytics (BD/LA) approach to improving learning. However, in the education of health care professionals, the application of BD/LA is limited to date. The authors discuss the potential advantages of the BD/LA approach for the process of learning via cognitive simulations. Using the lens of a cognitive model of radiograph interpretation with four phases (orientation, searching/scanning, feature detection, and decision making), they reanalyzed process data from a cognitive simulation of pediatric ankle radiography where 46 practitioners from three expertise levels classified 234 cases online. To illustrate the big data component, they highlight the data available in a digital environment (time-stamped, click-level process data). Learning analytics were illustrated using algorithmic computer-enabled approaches to process-level feedback.For each phase, the authors were able to identify examples of potentially useful BD/LA measures. For orientation, the trackable behavior of re-reviewing the clinical history was associated with increased diagnostic accuracy. For searching/scanning, evidence of skipping views was associated with an increased false-negative rate. For feature detection, heat maps overlaid on the radiograph can provide a metacognitive visualization of common novice errors. For decision making, the measured influence of sequence effects can reflect susceptibility to bias, whereas computer-generated path maps can provide insights into learners' diagnostic strategies.In conclusion, the augmented collection and dynamic analysis of learning process data within a cognitive simulation can improve feedback and prompt more precise reflection on a novice clinician's skill development.

  19. Oxytocin selectively facilitates learning with social feedback and increases activity and functional connectivity in emotional memory and reward processing regions.

    Science.gov (United States)

    Hu, Jiehui; Qi, Song; Becker, Benjamin; Luo, Lizhu; Gao, Shan; Gong, Qiyong; Hurlemann, René; Kendrick, Keith M

    2015-06-01

    In male Caucasian subjects, learning is facilitated by receipt of social compared with non-social feedback, and the neuropeptide oxytocin (OXT) facilitates this effect. In this study, we have first shown a cultural difference in that male Chinese subjects actually perform significantly worse in the same reinforcement associated learning task with social (emotional faces) compared with non-social feedback. Nevertheless, in two independent double-blind placebo (PLC) controlled between-subject design experiments we found OXT still selectively facilitated learning with social feedback. Similar to Caucasian subjects this OXT effect was strongest with feedback using female rather than male faces. One experiment performed in conjunction with functional magnetic resonance imaging showed that during the response, but not feedback phase of the task, OXT selectively increased activity in the amygdala, hippocampus, parahippocampal gyrus and putamen during the social feedback condition, and functional connectivity between the amygdala and insula and caudate. Therefore, OXT may be increasing the salience and reward value of anticipated social feedback. In the PLC group, response times and state anxiety scores during social feedback were associated with signal changes in these same regions but not in the OXT group. OXT may therefore have also facilitated learning by reducing anxiety in the social feedback condition. Overall our results provide the first evidence for cultural differences in social facilitation of learning per se, but a similar selective enhancement of learning with social feedback under OXT. This effect of OXT may be associated with enhanced responses and functional connectivity in emotional memory and reward processing regions.

  20. Volunteer feedback and perceptions after participation in a phase I, first-in-human Ebola vaccine trial: An anonymous survey

    Science.gov (United States)

    Dayer, Julie-Anne; Siegrist, Claire-Anne; Huttner, Angela

    2017-01-01

    The continued participation of volunteers in clinical trials is crucial to advances in healthcare. Few data are available regarding the satisfaction and impressions of healthy volunteers after participation in phase I trials, many of which lead to unexpected adverse events. We report feedback from over 100 adult volunteers who took part in a first-in-human trial conducted in a high-income country testing an experimental Ebola vaccine causing significant reactogenicity, as well as unexpected arthritis in one fifth of participants. The anonymous, internet-based satisfaction survey was sent by email to all participants upon their completion of this one-year trial; it asked 24 questions concerning volunteers’ motivations, impressions of the trial experience, and overall satisfaction. Answers were summarized using descriptive statistics. Of the 115 trial participants, 103 (90%) filled out the survey. Fifty-five respondents (53%) were male. Thirty-five respondents (34%) were healthcare workers, many of whom would deploy to Ebola-affected countries. All respondents cited scientific advancement as their chief motivation for participation, while 100/103 (97%) and 61/103 (59%) reported additional “humanitarian reasons” and potential protection from Ebolavirus, respectively. Although investigators had documented adverse events in 97% of trial participants, only 74 of 103 respondents (72%) recalled experiencing an adverse event. All reported an overall positive experience, and 93/103 (90%) a willingness to participate in future trials. Given the high level of satisfaction, no significant associations could be detected between trial experiences and satisfaction, even among respondents reporting adverse events lasting weeks or months. Despite considerable reactogenicity and unexpected vaccine-related arthritis, all survey respondents reported overall satisfaction. While this trial’s context was unique, the positive feedback is likely due at least in part to the intense

  1. Effective Instructor Feedback: Perceptions of Online Graduate Students

    Directory of Open Access Journals (Sweden)

    Beverley Getzlaf

    2009-07-01

    Full Text Available This descriptive study explored online graduate students' perceptions of effective instructor feedback. The objectives of the study were to determine the students’ perceptions of the content of effective instructor feedback (“what should be included in effective feedback?” and the process of effective instructor feedback (“how should effective feedback be provided?”. The participants were students completing health-related graduate courses offered exclusively online. Data were collected via a survey that included open ended questions inviting participants to share their perspectives regarding effective online instructor feedback. Thematic analysis revealed five major themes: student involvement/individualization, gentle guidance, being positively constructive, timeliness and future orientation. We conclude that effective instructor feedback has positive outcomes for the students. Future studies are warranted to investigate strategies to make feedback a mutual process between instructor and student that supports an effective feedback cycle.

  2. Analysis of prompt supercritical process with heat transfer and temperature feedback

    Institute of Scientific and Technical Information of China (English)

    ZHU BO; ZHU Qian; CHEN Zhiyun

    2009-01-01

    The prompt supercritical process of a nuclear reactor with temperature feedback and initial power as well as heat transfer with a big step reactivity (ρ0>β) is analyzed in this paper.Considering the effect of heat transfer on temperature of the reactor,a new model is set up.For any initial power,the variations of output power and reactivity with time are obtained by numerical method.The effects of the big inserted step reactivity and initial power on the prompt supercritical process are analyzed and discussed.It was found that the effect of heat transfer on the output power and reactivity can be neglected under any initial power,and the output power obtained by the adiabatic model is basically in accordance with that by the model of this paper,and the analytical solution can be adopted.The results provide a theoretical base for safety analysis and operation management of a power reactor.

  3. A key region in the human parietal cortex for processing proprioceptive hand feedback during reaching movements

    DEFF Research Database (Denmark)

    Reichenbach, Alexandra; Thielscher, Axel; Peer, Angelika

    2014-01-01

    neuroimaging studies have focused mainly on identifying the parts of the posterior parietal cortex (PPC) that contribute to visually guided movements. We used event-related TMS and force perturbations of the reaching hand to test whether the same sub-regions of the left PPC contribute to the processing...... of proprioceptive-only and of multi-sensory information about hand position when reaching for a visual target. TMS over two distinct stimulation sites elicited differential effects: TMS applied over the posterior part of the medial intraparietal sulcus (mIPS) compromised reaching accuracy when proprioception...... was the only sensory information available for correcting the reaching error. When visual feedback of the hand was available, TMS over the anterior intraparietal sulcus (aIPS) prolonged reaching time. Our results show for the first time the causal involvement of the posterior mIPS in processing proprioceptive...

  4. Navigating the Affordance Landscape: Feedback Control as a Process Model of Behavior and Cognition.

    Science.gov (United States)

    Pezzulo, Giovanni; Cisek, Paul

    2016-06-01

    We discuss how cybernetic principles of feedback control, used to explain sensorimotor behavior, can be extended to provide a foundation for understanding cognition. In particular, we describe behavior as parallel processes of competition and selection among potential action opportunities ('affordances') expressed at multiple levels of abstraction. Adaptive selection among currently available affordances is biased not only by predictions of their immediate outcomes and payoffs but also by predictions of what new affordances they will make available. This allows animals to purposively create new affordances that they can later exploit to achieve high-level goals, resulting in intentional action that links across multiple levels of control. Finally, we discuss how such a 'hierarchical affordance competition' process can be mapped to brain structure.

  5. Supervisor Perspective on the Process and Outcome of Giving Easy, Difficult, or No Feedback to Supervisees

    Science.gov (United States)

    Hoffman, Mary Ann; Hill, Clara E.; Holmes, Stacey E.; Freitas, Gary F.

    2005-01-01

    Fifteen counseling center supervisors were interviewed about 3 instances related to important feedback with an intern supervisee: in which the feedback was given easily, in which it was given reluctantly or with difficulty, and another in which it was not given. Supervisors indicated that easy feedback was most often about clinical problems, was…

  6. Problems Associated with Implementation of an Effective Upward Appraisal Feedback Process: An Experimental Field Study.

    Science.gov (United States)

    Antonioni, David

    1995-01-01

    Investigated the effects of written-upward appraisal reports (feedback) and performance reviews on the supervisory behavior of 96 managers. Results indicate that managers who received feedback did not improve their supervision more than managers who did not receive feedback. Discusses problems and provides recommendations for the design of an…

  7. Examining Feedback in an Instructional Video Game Using Process Data and Error Analysis. CRESST Report 817

    Science.gov (United States)

    Buschang, Rebecca E.; Kerr, Deirdre S.; Chung, Gregory K. W. K.

    2012-01-01

    Appropriately designed technology-based learning environments such as video games can be used to give immediate and individualized feedback to students. However, little is known about the design and use of feedback in instructional video games. This study investigated how feedback used in a mathematics video game about fractions impacted student…

  8. Modelling nitrite dynamics and associated feedback processes in the Benguela oxygen minimum zone

    Science.gov (United States)

    Mashifane, T. B.; Vichi, M.; Waldron, H. N.; Machu, E.; Garçonc, V.

    2016-08-01

    Understanding nitrite dynamics in oxygen minimum zones (OMZs) is a challenge as it represents an intermediary nitrogen species with a short turnover time. Nitrite is also reduced to nitrogen in OMZs, preventing its accumulation. This creates difficulties in detecting nitrite with colorimetric methods as concentrations may occur below detection limits in some regions. Nitrite concentrations are key to understanding intermediate nitrogen processes and their implication for nitrogen loss in OMZs. A coupled physical-biogeochemical model is applied in the Benguela OMZ to study nitrite dynamics and its associated feedback processes. Simulated results show occurrence of primary and secondary nitrite maxima in the Benguela shelf waters. The primary nitrite maxima in the Benguela are attributed to nitrification and nitrate assimilation as they occur in association with the nitracline. Secondary nitrite maxima accumulate in the Angola-Benguela Front (ABF) OMZ and are attributed to denitrification. The secondary nitrite maxima are consumed by anaerobic ammonium oxidation (anammox) off Walvis Bay. Nitrite maxima are restricted to the shelf off Walvis Bay and advected offshore in the ABF region. Interchanges between the poleward South Atlantic Central Water (SACW) and the equatorward, well-aerated Eastern South Atlantic Central Water (ESACW) drive the seasonality of nitrogen processes in the Benguela. Subsequent nitrite reduction in the Benguela OMZ leads to nitrous oxide production, with high concentrations occurring in the ABF region as a result of nitrification and denitrification. Off Walvis Bay, nitrous oxide production is low since nitrite is consumed by anammox. Nitrous oxide production occurs in thermocline, intermediate and deeper water masses in the ABF region. High N fluxes in the Benguela are attributed to nitrification as compared to anammox and denitrification. Results from this study demonstrate the role of intermediate nitrogen species in nitrogen feedback

  9. The XMM Cluster Survey: The interplay between the brightest cluster galaxy and the intra-cluster medium via AGN feedback

    CERN Document Server

    Stott, John P; Edge, Alastair C; Collins, Chris A; Hilton, Matt; Harrison, Craig D; Romer, A Kathy; Rooney, Philip J; Kay, Scott T; Miller, Christopher J; Sahlen, Martin; Lloyd-Davies, Ed J; Mehrtens, Nicola; Hoyle, Ben; Liddle, Andrew R; Viana, Pedro T P; McCarthy, Ian G; Schaye, Joop; Booth, C M

    2012-01-01

    Using a sample of 123 X-ray clusters and groups drawn from the XMM-Cluster Survey first data release, we investigate the interplay between the brightest cluster galaxy (BCG), its black hole, and the intra-cluster/group medium (ICM). It appears that for groups and clusters with a BCG likely to host significant AGN feedback, gas cooling dominates in those with Tx > 2 keV while AGN feedback dominates below. This may be understood through the sub-unity exponent found in the scaling relation we derive between the BCG mass and cluster mass over the halo mass range 10^13 2 keV) and again co-located with an effective fuel supply of dense, cooling gas. This demonstrates that the most massive black holes appear to know more about their host cluster than they do about their host galaxy. The results lead us to propose a physically motivated, empirical definition of 'cluster' and 'group', delineated at 2 keV.

  10. Survey of organic electrolytic processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-01

    The basic objectives of this study were to review the literature to determine the commercial status of electroorganic processes and to estimate whether there would be significant possible energy savings by introduction of electroorganic processes to replace conventional chemical processes for production of certain large-tonnage organic chemicals. A list was compiled of the 220 organic chemicals that were produced at greater than 10,000 tons per year in 1975 in the United States. Search of the Swann and of the Fichter Bibliographies of electroorganic literature yielded references on 95 of these compounds. By application of selection rules to obtain promising candidates, nine chemicals with diverse electrochemical processes were chosen for detailed process energy calculations. Parallel calculations were made for presently-used commercial chemical routes to these products. Two of the nine electrochemical processes, adiponitrile and methyl ethyl ketone, had energy savings in comparison to the corresponding chemical processes. Other more-energy-efficient electrochemical processes are likely among the above 95, although they remain to be identified.

  11. Point Clouds (2): Survey of Processing Software

    NARCIS (Netherlands)

    Lemmens, M.J.P.M.

    2014-01-01

    In this themed edition on collecting and processing point clouds, this article focuses on point cloud processing software aimed at creating DEMs or DSMs and products derived from these. The fi rst article of this diptych, published in the June issue of GIM International, focused on functionalities.

  12. Obtaining patient feedback in an outpatient lithotripsy service is facilitated by use of a touch-screen tablet (iPad™) survey.

    Science.gov (United States)

    Turney, B W; Reynard, J M

    2014-08-01

    There is now a requirement for every doctor in the UK to obtain patient feedback for revalidation. This can be an onerous and time-consuming task. The objective of this study was to evaluate a novel electronic patient feedback method in an outpatient lithotripsy service setting. Between September 2013 and January 2014, 100 patients attending an outpatient lithotripsy service in Oxford were asked to complete a selection of pre-approved NHS questions about the service they had received. Questions were presented on a tablet device (iPad™) and answered using the touch screen. Departmental staff were unaware of the questions in the survey. Patients were asked to complete the survey by an independent research nurse. Questions were created online in a free-to-use web-based survey application and presented on the tablet device in a user-friendly format via an application. Data were uploaded via wifi™ to the online system. Data were viewed, automatically analysed and displayed graphically. The age range of the patients surveyed was 20-80 years of age. All 100 patients completed the survey without difficulty. All patients answered every question. Data could be automatically viewed, analysed and presented graphically. This method of collecting patient feedback proved to be rapid and efficient. The feedback highlighted a high patient satisfaction with the lithotripsy service. A touch screen tablet device is an efficient and effective method of collecting truly objective patient feedback. This method of patient feedback could be employed in other clinical environments to collect data for revalidation purposes.

  13. Highly stable solution processed metal-halide perovskite lasers on nanoimprinted distributed feedback structures

    Science.gov (United States)

    Brenner, Philipp; Stulz, Mareike; Kapp, Dorothee; Abzieher, Tobias; Paetzold, Ulrich W.; Quintilla, Aina; Howard, Ian A.; Kalt, Heinz; Lemmer, Uli

    2016-10-01

    We report on the performance and stability of distributed feedback lasers based on the solution-processed methylammonium lead iodide perovskite (CH3NH3PbI3). The CH3NH3PbI3 layers are processed via solution-casting in ambient atmosphere onto nanoimprinted second order Bragg gratings. This way, we achieve highly polarized surface-emitted lasing at room temperature with a linewidth of less than 0.2 nm and a laser threshold of 120 kW/cm2. The lasing is stable; no change in the laser emission within 15 h of pulsed excitation with a repetition rate of 1 kHz (corresponding to >5 × 107 pulses) is observed, exceeding the stability achieved for solution processed organic semiconductor lasers. Furthermore, adjustment of the grating period allowed the lasing wavelength to be varied over the entire bandwidth of the amplified spontaneous emission (between 781 and 794 nm). The fabrication process of nanoimprinting followed by solution-casting of the gain material demonstrates that stable CH3NH3PbI3 lasers are compatible with scalable production technologies and offers a route towards electrically pumped diode architectures.

  14. Survey of metallurgical recycling processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pemsler, J.P.

    1979-03-01

    In the year 2000, the US will consume about 3.2 x 10/sup 15/ Btu to produce the seven major nonferrous metals Al, Cu, Zn, Pb, Ni, Mg, and Ti. Of this amount, 82% will be used in the production of Al. It is projected that 0.6 x 10/sup 15/ Btu will be saved by the recycle of secondary metals. Major opportunities for increasing the extent of recycle and thereby increasing the energy savings are discussed. An inherent feature in the energistics of recycle is that physical processes such as magnetic separation, density separations, melting, and in some instances vaporization are far less energy intensive than are chemical processes associated with dissolution and electrowinning. It is in the domain of scrap of complex composition and physical form, difficult to handle by existing technology, that opportunities exist for new chemical recycle technology. Recycle of scrap metal of adequate grade is currently achieved through pyrometallurgical processes which, in many cases, are not very energy intensive as compared with hydrometallurgical processes. Preliminary flowsheets are presented for the recovery of value metals from batteries considered for use in vehicular propulsion and load leveling applications. The battery types examined are lead/acid, nickel/zinc, nickel/iron, zinc/chlorine, lithium-aluminum/iron sulfide, and sodium/sulfur. A flow sheet has been outlined for an integrated hydrometallurgical process to treat low-grade copper scrap. A fully integrated hydrometallurgical process is outlined, and costs and energy consumption are derived, for recovering zinc metal from electric furnace flue dusts. Costs and energy are high and the process does not appear to warrant development at this time. Improvement in the recycle of magnesium is associated primarily with improved recycle in the Al industry where Mg is an important alloy additive. Ni and Ti recycle are associated with improved collection and sorting of stainless steel and specialty alloys.

  15. A Panchromatic Survey of Post-starburst Mergers: searching for feedback

    CERN Document Server

    De Propris, Roberto

    2014-01-01

    We consider the morphology, stellar populations, structure and AGN activity of 10 post-starburst (K+A) galaxies with HST observations, full spectral coverage in the optical, spectral energy distributions from 0.2 to 160 $\\mu$m, X-ray and radio data. Our results show that the PSG phenomenon is related to mergers and interactions, and that star formation was likely triggered during close passes prior to final coalescence. We performed a detailed qualitative analysis of the observed light distribution, including low-surface brightness tidal features and color profiles, in high-resolution multi-band imaging with HST. We find evidence that star formation was centrally concentrated and that quenching took place from the inside-out, consistent with the occurrence of a feedback episode. Most of our PSGs contain massive bulges and therefore should host supermassive black holes. We search for AGN activity in spectra (line ratios), optical variability, X-ray emission at 0.5--7.0 KeV and radio emission at 20cm: all four ...

  16. Mobile Access to ClinicalConnect: A User Feedback Survey on Usability, Productivity, and Quality

    OpenAIRE

    Eapen, Bell Raj; Chapman, Barbara

    2015-01-01

    Background ClinicalConnect, a federated clinical viewer for South West Ontario, Canada, launched a mobile interface in June 2012. Objective The aim of the study was to assess usability of the mobile interface and the perceived impact on productivity of health care providers and quality of healthcare delivery. Methods A survey was conducted using the System Usability Scale (SUS) and questionnaires designed to measure productivity and quality based on Canada Health Infoway's Benefits Evaluation...

  17. Inferring Instantaneous, Multivariate and Nonlinear Sensitivities for the Analysis of Feedback Processes in a Dynamical System: Lorenz Model Case Study

    Science.gov (United States)

    Aires, Filipe; Rossow, William B.; Hansen, James E. (Technical Monitor)

    2001-01-01

    A new approach is presented for the analysis of feedback processes in a nonlinear dynamical system by observing its variations. The new methodology consists of statistical estimates of the sensitivities between all pairs of variables in the system based on a neural network modeling of the dynamical system. The model can then be used to estimate the instantaneous, multivariate and nonlinear sensitivities, which are shown to be essential for the analysis of the feedbacks processes involved in the dynamical system. The method is described and tested on synthetic data from the low-order Lorenz circulation model where the correct sensitivities can be evaluated analytically.

  18. Signatures of AGN feedback

    Science.gov (United States)

    Wylezalek, Dominika; Zakamska, Nadia L.; MaNGA-GMOS Team

    2017-01-01

    Feedback from actively accreting SMBHs (Active Galactic Nuclei, AGN) is now widely considered to be the main driver in regulating the growth of massive galaxies. Observational proof for this scenario has, however, been hard to come by. Many attempts at finding a conclusive observational proof that AGN may be able to quench star formation and regulate the host galaxies' growth have shown that this problem is highly complex.I will present results from several projects that focus on understanding the power, reach and impact of feedback processes exerted by AGN. I will describe recent efforts in our group of relating feedback signatures to the specific star formation rate in their host galaxies, where our results are consistent with the AGN having a `negative' impact through feedback on the galaxies' star formation history (Wylezalek+2016a,b). Furthermore, I will show that powerful AGN-driven winds can be easily hidden and not be apparent in the integrated spectrum of the galaxy. This implies that large IFU surveys, such as the SDSS-IV MaNGA survey, might uncover many previously unknown AGN and outflows that are potentially very relevant for understanding the role of AGN in galaxy evolution (Wylezalek+2016c)!

  19. Supporting Third Year Medical Students' Skill Acquisition and Self-Efficacy with Coping Models and Process Feedback during Laparoscopic Knot Tying Simulation

    Directory of Open Access Journals (Sweden)

    Michael S. Dempsey

    2017-07-01

    Full Text Available Background: During the third year general surgery clerkship, medical students are required to develop laparoscopic knot-tying skills. Knot-tying skills studies often rely on objective variables (e.g., time, materials used, number of iterations that lend themselves to correlational analysis of pre- and post-intervention skill level. This study differs by examining how instructional interventions—role modeling and feedback—affect medical students' skill acquisition and self-efficacy during a laparoscopic surgical simulation training session.Methods: Seventy-eight surgical clerkship students were assigned randomly to one cell of a 2X2 factorial design. Participants observed one of two types of role modeling (expert vs. coping and received either process-oriented or outcome-oriented feedback during a 30-min laparoscopic training session. Participants also completed several surveys that assessed their interest in surgery and their self-efficacy for laparoscopic knot tying.Results: Coping model groups tended to perform better on the knot tying task, though this was less the case in the presence of outcome feedback. Expert model groups slightly outperformed the coping model group on the peg transfer task, but in the presence of outcome feedback they reported the lowest satisfaction with their performance and the lowest self-efficacy for the knot tying task. The coping model combined with process feedback had a positive influence on students' efficiency in learning the task, on their satisfaction with their performance, and on their self-efficacy for laparoscopic knot typing.Conclusions: Results are discussed relative to self-regulated learning theory.

  20. Supporting Learners' Agentic Engagement with Feedback: A Systematic Review and a Taxonomy of Recipience Processes

    Science.gov (United States)

    Winstone, Naomi E.; Nash, Robert A.; Parker, Michael; Rowntree, James

    2017-01-01

    Much has been written in the educational psychology literature about effective feedback and how to deliver it. However, it is equally important to understand how learners actively receive, engage with, and implement feedback. This article reports a systematic review of the research evidence pertaining to this issue. Through an analysis of 195…

  1. Reconfiguring and Realigning the Assessment Feedback Processes for an Undergraduate Criminology Degree

    Science.gov (United States)

    Case, Stephen

    2007-01-01

    A reconfigured and realigned system of assessment feedback was implemented with undergraduates taking criminology modules at Swansea University. The reformulated system integrated explicit engagement with assessment criteria in feedback given on an electronic template form with the use of a statement bank and the offer of follow-up, feedback…

  2. Reconfiguring and Realigning the Assessment Feedback Processes for an Undergraduate Criminology Degree

    Science.gov (United States)

    Case, Stephen

    2007-01-01

    A reconfigured and realigned system of assessment feedback was implemented with undergraduates taking criminology modules at Swansea University. The reformulated system integrated explicit engagement with assessment criteria in feedback given on an electronic template form with the use of a statement bank and the offer of follow-up, feedback…

  3. Supporting Learners' Agentic Engagement with Feedback: A Systematic Review and a Taxonomy of Recipience Processes

    Science.gov (United States)

    Winstone, Naomi E.; Nash, Robert A.; Parker, Michael; Rowntree, James

    2017-01-01

    Much has been written in the educational psychology literature about effective feedback and how to deliver it. However, it is equally important to understand how learners actively receive, engage with, and implement feedback. This article reports a systematic review of the research evidence pertaining to this issue. Through an analysis of 195…

  4. No Longer a Teacher Monologue--Involving EFL Writing Learners in Teachers' Assessment and Feedback Processes

    Science.gov (United States)

    Huang, Shu-Chen

    2016-01-01

    This paper reports the design of learning-oriented formative assessments in an EFL writing course that involved learners in regularly responding to teacher feedback. Following major assessment and feedback frameworks developed recently, these formative assessments were explicated in three aspects: the scheduling of learning and assessment…

  5. Chandra survey of nearby highly inclined disk galaxies - IV. New insights into the working of stellar feedback

    Science.gov (United States)

    Wang, Q. Daniel; Li, Jiangtao; Jiang, Xiaochuan; Fang, Taotao

    2016-04-01

    Galaxy evolution is regulated by the interplay between galactic discs and their surrounding medium. We study this interplay by examining how the galactic coronal emission efficiency of stellar feedback depends on the (surface and specific) star formation rates (SFRs) and other parameters for a sample of 52 Chandra-observed nearby highly inclined disc galaxies. We first measure the star-forming galactic disc sizes, as well as the SFRs of these galaxies, using data from the Wide-Field Infrared Survey Explorer, and then show that (1) the specific 0.5-2 keV luminosity of the coronal emission correlates with the specific SFR in a sub-linear fashion: on average, LX/LK∝(SFR/M*)Γ with Γ = 0.29 ± 0.12; (2) the efficiency of the emission LX/SFR decreases with increasing surface SFR (ISFR; Γ = -0.44 ± 0.12); and (3) the characteristic temperature of the X-ray-emitting plasma weakly correlates with ISFR (Γ = 0.08 ± 0.04). These results, somewhat surprising and anti-intuitive, suggest that (i) the linear correlation between LX and SFR, as commonly presented, is largely due to the correlation of these two parameters with galaxy mass; (ii) much of the mechanical energy from stellar feedback likely drives global outflows with little X-ray cooling and with a mass-loading efficiency decreasing fast with increasing ISFR (Γ ≲ -0.5); (iii) these outflows heat and inflate the medium around the galactic disks of massive galaxies, reducing its radiative cooling rate, whereas for relatively low-mass galaxies, the energy in the outflows is probably dissipated in regions far away from the galactic discs.

  6. A 4 GS/sec Instability Feedback Processing System for Intra-bunch Instabilities

    CERN Document Server

    Dusatko, J; Fox, J D; Pollock, K; Rivetta, C H; Turgut, O; Hofle, W

    2013-01-01

    We present the architecture and implementation overview of a proof-of-principle digital signal processing system developed to study control of Electron-Cloud and Transverse Mode Coupling Instabilities (TMCI) in the CERN SPS. This system is motivated by intensity increases planned as part of the High Luminosity LHC upgrade. It is based on a reconfigurable processing architecture which samples intra-bunch motion and applies correction signals at a 4GSa/s rate, allowing multiple samples across a single 3.2ns SPS bunch. This initial demonstration system is a rapidly developed prototype consisting of both commercial and custom- designed hardware that implements feedback control on a single bunch. It contains a high speed ADC and DAC, capable of sampling at up to 4GSa/s, with a 16-tap FIR control filter for each bunch sample slice. Other system features include a timing subsystem to synchronize the sampling to the injection and the bunch 1 markers, the capability of generating arbitrary time domain signals to drive...

  7. Survey: interpolation methods in medical image processing.

    Science.gov (United States)

    Lehmann, T M; Gönner, C; Spitzer, K

    1999-11-01

    Image interpolation techniques often are required in medical imaging for image generation (e.g., discrete back projection for inverse Radon transform) and processing such as compression or resampling. Since the ideal interpolation function spatially is unlimited, several interpolation kernels of finite size have been introduced. This paper compares 1) truncated and windowed sinc; 2) nearest neighbor; 3) linear; 4) quadratic; 5) cubic B-spline; 6) cubic; g) Lagrange; and 7) Gaussian interpolation and approximation techniques with kernel sizes from 1 x 1 up to 8 x 8. The comparison is done by: 1) spatial and Fourier analyses; 2) computational complexity as well as runtime evaluations; and 3) qualitative and quantitative interpolation error determinations for particular interpolation tasks which were taken from common situations in medical image processing. For local and Fourier analyses, a standardized notation is introduced and fundamental properties of interpolators are derived. Successful methods should be direct current (DC)-constant and interpolators rather than DC-inconstant or approximators. Each method's parameters are tuned with respect to those properties. This results in three novel kernels, which are introduced in this paper and proven to be within the best choices for medical image interpolation: the 6 x 6 Blackman-Harris windowed sinc interpolator, and the C2-continuous cubic kernels with N = 6 and N = 8 supporting points. For quantitative error evaluations, a set of 50 direct digital X rays was used. They have been selected arbitrarily from clinical routine. In general, large kernel sizes were found to be superior to small interpolation masks. Except for truncated sinc interpolators, all kernels with N = 6 or larger sizes perform significantly better than N = 2 or N = 3 point methods (p cubic 6 x 6 interpolator with continuous second derivatives, as defined in (24), can be recommended for most common interpolation tasks. It appears to be the fastest

  8. Improved Disturbance Observer (DOB) Based Advanced Feedback Control for Optimal Operation of a Mineral Grinding Process%Improved Disturbance Observer (DOB) Based Advanced Feedback Control for Optimal Operation of a Mineral Grinding Process

    Institute of Scientific and Technical Information of China (English)

    周平; 向波; 柴天佑

    2012-01-01

    Advanced feedback control for optimal operation of mineral grinding process is usually based on the model predictive control (MPC) dynamic optimization. Since the MPC does not handle disturbances directly by controller design, it cannot achieve satisfactory effects in controlling complex grinding processes in the presence of strong disturbances and large uncertainties. In this paper, an improved disturbance observer (DOB) based MPC advanced feedback control is proposed to control the multivariable grinding operation. The improved DOB is based on the optimal achievable H 2 performance and can deal with disturbance observation for the nonminimum-phase delay systems. In this DOB-MPC advanced feedback control, the higher-level optimizer computes the optimal operation points by maximize the profit function and passes them to the MPC level. The MPC acts as a presetting controller and is employed to generate proper pre-setpoint for the lower-level basic feedback control system. The DOB acts as a compensator and improves the operation performance by dynamically compensating the setpoints for the basic control system according to the observed various disturbances and plant uncertainties. Several simulations are performed to demonstrate the proposed control method for grinding process operation.

  9. AIED 2009 Workshops Proceeedings Volume 10: Natural Language Processing in Support of Learning: Metrics, Feedback and Connectivity

    NARCIS (Netherlands)

    Dessus, Philippe; Trausan-Matu, Stefan; Van Rosmalen, Peter; Wild, Fridolin

    2009-01-01

    Dessus, P., Trausan-Matu, S., Van Rosmalen, P., & Wild, F. (Eds.) (2009). AIED 2009 Workshops Proceedings Volume 10 Natural Language Processing in Support of Learning: Metrics, Feedback and Connectivity. In S. D. Craig & D. Dicheva (Eds.), AIED 2009: 14th International Conference in Artificial

  10. The MAGNUM survey: Positive feedback in the nuclear region of NGC 5643 suggested by MUSE

    CERN Document Server

    Cresci, G; Zibetti, S; Risaliti, G; Carniani, S; Mannucci, F; Gallazzi, A; Maiolino, R; Balmaverde, B; Brusa, M; Capetti, A; Cicone, C; Feruglio, C; Bland-Hawthorn, J; Nagao, T; Oliva, E; Salvato, M; Sani, E; Tozzi, P; Urrutia, T; Venturi, G

    2015-01-01

    We study the ionization and kinematics of the ionized gas in the nuclear region of the barred Seyfert 2 galaxy NGC~5643 using MUSE integral field observations in the framework of the MAGNUM (Measuring Active Galactic Nuclei Under MUSE Microscope) survey. The data were used to identify regions with different ionization conditions and to map the gas density and the dust extinction. We find evidence for a double sided ionization cone, possibly collimated by a dusty structure surrounding the nucleus. At the center of the ionization cone, outflowing ionized gas is revealed as a blueshifted, asymmetric wing of the [OIII] emission line, up to projected velocity v(10)~-450 km/s. The outflow is also seen as a diffuse, low luminosity radio and X-ray jet, with similar extension. The outflowing material points in the direction of two clumps characterized by prominent line emission with spectra typical of HII regions, located at the edge of the dust lane of the bar. We propose that the star formation in the clumps is due ...

  11. Feedbacks between aeolian processes and ecosystem change in a degraded desert grassland in the southwestern US

    Science.gov (United States)

    Li, Junran

    2015-04-01

    The desert grassland in the southwestern US has undergone dramatic vegetation changes with many areas of grassland becoming shrublands in the last 150 years. A principle manifestation of such a land degradation is the wide distribution of fertile islands in once-homogenous landscapes, which changed soil resource redistributions through the movement of resources from plant interspaces to the area beneath plant canopies. A great deal of work has examined the role of water in nutrient reduction and enforcement of islands of fertility in the semiarid landscapes. However, little is known on the role of wind in the removal or redistribution of soil resources, and further the feedbacks between wind and ecosystem change in this area. In spring 2004, a vegetation removal experiment was established in the northern Chihuahuan Desert, southern New Mexico, where vegetation cover on the experimental plots were manually reduced to various levels to study the entire suite of aeolian processes, including erosion, transport, and deposition in creating and enforcing patchy distribution of vegetation. This experiment has been continually maintained for more than ten years, with the sampling and observation of vegetation cover, soil nutrients, sediment flux, topography, and plant physiology. The experimental results highlighted that the aeolian processes in the Chihuahuan Desert are able to change soil properties and community composition in as short as 3 three years. Further, the removal of grasses by 75% may trigger a very substantial increase of wind erosion and the removal of grass by 50% could cause significant amount of C and N loss due to wind erosion. Last but not least, the change of the spatial distribution of soil C and the micro-topography both point to the fact that aeolian processes contribute substantially to the dynamics of fertile islands in this desert grassland.

  12. CMF Signal Processing Method Based on Feedback Corrected ANF and Hilbert Transformation

    Directory of Open Access Journals (Sweden)

    Tu Yaqing

    2014-02-01

    Full Text Available In this paper, we focus on CMF signal processing and aim to resolve the problems of precision sharp-decline occurrence when using adaptive notch filters (ANFs for tracking the signal frequency for a long time and phase difference calculation depending on frequency by the sliding Goertzel algorithm (SGA or the recursive DTFT algorithm with negative frequency contribution. A novel method is proposed based on feedback corrected ANF and Hilbert transformation. We design an index to evaluate whether the ANF loses the signal frequency or not, according to the correlation between the output and input signals. If the signal frequency is lost, the ANF parameters will be adjusted duly. At the same time, singular value decomposition (SVD algorithm is introduced to reduce noise. And then, phase difference between the two signals is detected through trigonometry and Hilbert transformation. With the frequency and phase difference obtained, time interval of the two signals is calculated. Accordingly, the mass flow rate is derived. Simulation and experimental results show that the proposed method always preserves a constant high precision of frequency tracking and a better performance of phase difference measurement compared with the SGA or the recursive DTFT algorithm with negative frequency contribution

  13. Processing of Own Hand Visual Feedback during Object Grasping in Ventral Premotor Mirror Neurons.

    Science.gov (United States)

    Maranesi, Monica; Livi, Alessandro; Bonini, Luca

    2015-08-26

    Mirror neurons (MNs) discharge during action execution as well as during observation of others' actions. Our own actions are those that we have the opportunity to observe more frequently, but no study thus far to our knowledge has addressed the issue of whether, and to what extent, MNs can code own hand visual feedback (HVF) during object grasping. Here, we show that MNs of the ventral premotor area F5 of macaque monkeys are particularly sensitive to HVF relative to non-MNs simultaneously recorded in the same penetrations. Importantly, the HVF effect is more evident on MN activity during hand-object interaction than during the hand-shaping phase. Furthermore, the increase of MN activity induced by HVF and others' actions observed from a subjective perspective were positively correlated. These findings indicate that at least part of ventral premotor MNs can process the visual information coming from own hand interacting with objects, likely playing a role in self-action monitoring. We show that mirror neurons (MNs) of area F5 of the macaque, in addition to encoding others' observed actions, are particularly sensitive, relative to simultaneously recorded non-MNs, to the sight of the monkey's own hand during object grasping, likely playing a role in self-action monitoring. Copyright © 2015 the authors 0270-6474/15/3511824-06$15.00/0.

  14. Climate-sensitive feedbacks between hillslope processes and fluvial erosion in sediment-driven incision models

    Science.gov (United States)

    Skov, Daniel S.; Egholm, David L.

    2016-04-01

    Surface erosion and sediment production seem to have accelerated globally as climate cooled in the Late Cenozoic, [Molnar, P. 2004, Herman et al 2013]. Glaciers emerged in many high mountain ranges during the Quaternary, and glaciation therefore represents a likely explanation for faster erosion in such places. Still, observations and measurements point to increases in erosion rates also in landscapes where erosion is driven mainly by fluvial processes [Lease and Ehlers (2013), Reusser (2004)]. Flume experiments and fieldwork have shown that rates of incision are to a large degree controlled by the sediment load of streams [e.g. Sklar and Dietrich (2001), Beer and Turowski (2015)]. This realization led to the formulation of sediment-flux dependent incision models [Sklar and Dietrich (2004)]. The sediment-flux dependence links incision in the channels to hillslope processes that supply sediment to the channels. The rates of weathering and soil transport on the hillslopes are processes that are likely to respond to changing temperatures, e.g. because of vegetation changes or the occurrence of frost. In this study, we perform computational landscape evolution experiments, where the coupling between fluvial incision and hillslope processes is accounted for by coupling a sediment-flux-dependent model for fluvial incision to a climate-dependent model for weathering and hillslope sediment transport. The computational experiments first of all demonstrate a strong positive feedback between channel and hillslope processes. In general, faster weathering leads to higher rates of channel incision, which further increases the weathering rates, mainly because of hillslope steepening. Slower weathering leads to the opposite result. The experiments also demonstrate, however, that the feedbacks vary significantly between different parts of a drainage network. For example, increasing hillslope sediment production may accelerate incision in the upper parts of the catchment, while at

  15. Sensory Processing: Advances in Understanding Structure and Function of Pitch-Shifted Auditory Feedback in Voice Control

    Directory of Open Access Journals (Sweden)

    Charles R Larson

    2016-02-01

    Full Text Available The pitch-shift paradigm has become a widely used method for studying the role of voice pitch auditory feedback in voice control. This paradigm introduces small, brief pitch shifts in voice auditory feedback to vocalizing subjects. The perturbations trigger a reflexive mechanism that counteracts the change in pitch. The underlying mechanisms of the vocal responses are thought to reflect a negative feedback control system that is similar to constructs developed to explain other forms of motor control. Another use of this technique requires subjects to voluntarily change the pitch of their voice when they hear a pitch shift stimulus. Under these conditions, short latency responses are produced that change voice pitch to match that of the stimulus. The pitch-shift technique has been used with magnetoencephalography (MEG and electroencephalography (EEG recordings, and has shown that at vocal onset there is normally a suppression of neural activity related to vocalization. However, if a pitch-shift is also presented at voice onset, there is a cancellation of this suppression, which has been interpreted to mean that one way in which a person distinguishes self-vocalization from vocalization of others is by a comparison of the intended voice and the actual voice. Studies of the pitch shift reflex in the fMRI environment show that the superior temporal gyrus (STG plays an important role in the process of controlling voice F0 based on auditory feedback. Additional studies using fMRI for effective connectivity modeling show that the left and right STG play critical roles in correcting for an error in voice production. While both the left and right STG are involved in this process, a feedback loop develops between left and right STG during perturbations, in which the left to right connection becomes stronger, and a new negative right to left connection emerges along with the emergence of other feedback loops within the cortical network tested.

  16. Chandra survey of nearby highly inclined disk galaxies -- IV: New insights into the working of stellar feedback

    CERN Document Server

    Wang, Q Daniel; Jiang, Xiaochuan; Fang, Taotao

    2015-01-01

    Galaxy evolution is regulated by the interplay between galactic disks and their surrounding medium. We study this interplay by examining how the galactic coronal emission efficiency of stellar feedback depends on the (surface and specific) star formation rates (SFRs) and other parameters for a sample of 52 Chandra-observed nearby highly inclined disk galaxies. We first measure the star forming galactic disk sizes, as well as the SFRs of these galaxies, using data from the Wide-Field Infrared Survey Explorer, and then show that 1) the specific 0.5-2~keV luminosity of the coronal emission correlates with the specific SFR in a {\\sl sub-linear} fashion: on average, $L_X/L_K \\propto (SFR/M_*)^{\\Gamma}$ with $\\Gamma =0.29\\pm0.12$; 2) the efficiency of the emission $ L_X/SFR$ decreases with increasing surface SFR ($I_{SFR}$; $\\Gamma = -0.44\\pm0.12$); and 3) the characteristic temperature of the X-ray-emitting plasma weakly correlates with $I_{SFR}$ ($\\Gamma = 0.08\\pm0.04$). These results, somewhat surprising and ant...

  17. Bundle adjustment for data processing of theodolite industrial surveying system

    Institute of Scientific and Technical Information of China (English)

    邹峥嵘; 丁晓利; 曾卓乔; 何凭宗

    2001-01-01

    The photogrammetric bundle adjustment was used in data processing of electronic theodolite industrial surveying system by converting angular observations into virtual photo coordinates. The developed algorithm has ability of precision estimation and data-snooping, do not need initial values of exterior orientation elements and object point coordinates. The form of control condition for the system is quite flexible. Neither centering nor leveling is the theodolite needed and the lay-out of theodolite position is flexible when the system is used for precise survey. Experiments carried out in test field verify the validity of the data processing method.

  18. Functional role of delta and theta band oscillations for auditory feedback processing during vocal pitch motor control.

    Science.gov (United States)

    Behroozmand, Roozbeh; Ibrahim, Nadine; Korzyukov, Oleg; Robin, Donald A; Larson, Charles R

    2015-01-01

    The answer to the question of how the brain incorporates sensory feedback and links it with motor function to achieve goal-directed movement during vocalization remains unclear. We investigated the mechanisms of voice pitch motor control by examining the spectro-temporal dynamics of EEG signals when non-musicians (NM), relative pitch (RP), and absolute pitch (AP) musicians maintained vocalizations of a vowel sound and received randomized ± 100 cents pitch-shift stimuli in their auditory feedback. We identified a phase-synchronized (evoked) fronto-central activation within the theta band (5-8 Hz) that temporally overlapped with compensatory vocal responses to pitch-shifted auditory feedback and was significantly stronger in RP and AP musicians compared with non-musicians. A second component involved a non-phase-synchronized (induced) frontal activation within the delta band (1-4 Hz) that emerged at approximately 1 s after the stimulus onset. The delta activation was significantly stronger in the NM compared with RP and AP groups and correlated with the pitch rebound error (PRE), indicating the degree to which subjects failed to re-adjust their voice pitch to baseline after the stimulus offset. We propose that the evoked theta is a neurophysiological marker of enhanced pitch processing in musicians and reflects mechanisms by which humans incorporate auditory feedback to control their voice pitch. We also suggest that the delta activation reflects adaptive neural processes by which vocal production errors are monitored and used to update the state of sensory-motor networks for driving subsequent vocal behaviors. This notion is corroborated by our findings showing that larger PREs were associated with greater delta band activity in the NM compared with RP and AP groups. These findings provide new insights into the neural mechanisms of auditory feedback processing for vocal pitch motor control.

  19. Wetland eco-engineering: measuring and modeling feedbacks of oxidation processes between plants and clay-rich material

    Science.gov (United States)

    Saaltink, Rémon; Dekker, Stefan C.; Griffioen, Jasper; Wassen, Martin J.

    2016-09-01

    Interest is growing in using soft sediment as a foundation in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here, dredging some of the clay-rich lake-bed sediment and using it to construct wetland will soon begin. Natural processes will be utilized during and after construction to accelerate ecosystem development. Knowing that plants can eco-engineer their environment via positive or negative biogeochemical plant-soil feedbacks, we conducted a 6-month greenhouse experiment to identify the key biogeochemical processes in the mud when Phragmites australis is used as an eco-engineering species. We applied inverse biogeochemical modeling to link observed changes in pore water composition to biogeochemical processes. Two months after transplantation we observed reduced plant growth and shriveling and yellowing of foliage. The N : P ratios of the plant tissue were low, and these were affected not by hampered uptake of N but by enhanced uptake of P. Subsequent analyses revealed high Fe concentrations in the leaves and roots. Sulfate concentrations rose drastically in our experiment due to pyrite oxidation; as reduction of sulfate will decouple Fe-P in reducing conditions, we argue that plant-induced iron toxicity hampered plant growth, forming a negative feedback loop, while simultaneously there was a positive feedback loop, as iron toxicity promotes P mobilization as a result of reduced conditions through root death, thereby stimulating plant growth and regeneration. Given these two feedback mechanisms, we propose the use of Fe-tolerant species rather than species that thrive in N-limited conditions. The results presented in this study demonstrate the importance of studying the biogeochemical properties of the situated sediment and the feedback mechanisms between plant and soil prior to finalizing the design of the eco-engineering project.

  20. Functional role of delta and theta band oscillations for auditory feedback processing during vocal pitch motor control

    Directory of Open Access Journals (Sweden)

    Roozbeh eBehroozmand

    2015-03-01

    Full Text Available The answer to the question of how the brain incorporates sensory feedback and links it with motor function to achieve goal-directed movement during vocalization remains unclear. We investigated the mechanisms of voice pitch motor control by examining the spectro-temporal dynamics of EEG signals when non-musicians (NM, relative pitch (RP and absolute pitch (AP musicians maintained vocalizations of a vowel sound and received randomized ±100 cents pitch-shift stimuli in their auditory feedback. We identified a phase-synchronized (evoked fronto-central activation within the theta band (5-8 Hz that temporally overlapped with compensatory vocal responses to pitch-shifted auditory feedback and was significantly stronger in RP and AP musicians compared with non-musicians. A second component involved a non-phase-synchronized (induced frontal activation within the delta band (1-4 Hz that emerged at approximately 1 second after the stimulus onset. The delta activation was significantly stronger in the NM compared with RP and AP groups and correlated with the pitch rebound error (PRE, indicating the degree to which subjects failed to re-adjust their voice pitch to baseline after the stimulus offset. We propose that the evoked theta is a neurophysiological marker of enhanced pitch processing in musicians and reflects mechanisms by which humans incorporate auditory feedback to control their voice pitch. We also suggest that the delta activation reflects adaptive neural processes by which vocal production errors are monitored and used to update the state of sensory-motor networks for driving subsequent vocal behaviors. This notion is corroborated by our findings showing that larger PREs were associated with greater delta band activity in the NM compared with RP and AP groups. These findings provide new insights into the neural mechanisms of auditory feedback processing for vocal pitch motor control.

  1. Event-related potential studies of outcome processing and feedback-guided learning

    Directory of Open Access Journals (Sweden)

    René eSan Martín

    2012-11-01

    Full Text Available In order to control behavior in an adaptive manner the brain has to learn how some situations and actions predict positive or negative outcomes. During the last decade cognitive neuroscientists have shown that the brain is able to evaluate and learn from outcomes within a few hundred milliseconds of their occurrence. This research has been primarily focused on the feedback-related negativity (FRN and the P3, two event-related potential (ERP components that are elicited by outcomes. The FRN is a frontally distributed negative-polarity ERP component that typically reaches its maximal amplitude 250 ms after outcome presentation and tends to be larger for negative than for positive outcomes. The FRN has been associated with activity in the anterior cingulate cortex. The P3 (~300-600 ms is a parietally distributed positive-polarity ERP component that tends to be larger for large magnitude than for small magnitude outcomes. The neural sources of the P3 are probably distributed over different regions of the cortex. This paper examines the theories that have been proposed to explain the functional role of these two ERP components during outcome processing. Special attention is paid to extant literature addressing how these ERP components are modulated by outcome valence (negative vs. positive, outcome magnitude (large vs. small, outcome probability (unlikely vs. likely and behavioral adjustment. The literature offers few generalizable conclusions, but is beset with a number of inconsistencies across studies. This paper discusses the potential reasons for these inconsistencies and points out some challenges that will shape the field over the next decade.

  2. The Dark Energy Survey Data Processing and Calibration System

    CERN Document Server

    Mohr, Joseph J; Bertin, Emmanuel; Daues, Gregory E; Desai, Shantanu; Gower, Michelle; Gruendl, Robert; Hanlon, William; Kuropatkin, Nikolay; Lin, Huan; Marriner, John; Petravick, Don; Sevilla, Ignacio; Swanson, Molly; Tomashek, Todd; Tucker, Douglas; Yanny, Brian

    2012-01-01

    The Dark Energy Survey (DES) is a 5000 deg2 grizY survey reaching characteristic photometric depths of 24th magnitude (10 sigma) and enabling accurate photometry and morphology of objects ten times fainter than in SDSS. Preparations for DES have included building a dedicated 3 deg2 CCD camera (DECam), upgrading the existing CTIO Blanco 4m telescope and developing a new high performance computing (HPC) enabled data management system (DESDM). The DESDM system will be used for processing, calibrating and serving the DES data. The total data volumes are high (~2PB), and so considerable effort has gone into designing an automated processing and quality control system. Special purpose image detrending and photometric calibration codes have been developed to meet the data quality requirements, while survey astrometric calibration, coaddition and cataloging rely on new extensions of the AstrOmatic codes which now include tools for PSF modeling, PSF homogenization, PSF corrected model fitting cataloging and joint mode...

  3. Data acquisition and processing - helicopter radiometric survey, Krageroe, 1998

    CERN Document Server

    Beard, L P

    2000-01-01

    On 07 October 1998 a helicopter radiometric survey was flown in the vicinity of Krageroe municipality. The purpose of the survey was to provide radiometric information to help assess radon hazard from radioactive rocks in the area. A total of 60 line-kilometres of radiometric data were acquired in a single flight, covering an area of approximately 3 square km with a 50-m line spacing. The data were collected by Geological Survey of Norway (NGU) personnel and processed at NGU. Radiometric data were reduced using the three-channel procedure recommended by the International Atomic Energy Association. All data were gridded using square cells with 30-m sides and geophysical maps were produced at a scale of 1:5000. This report covers aspects of data acquisition and processing (Author)

  4. Attention to color sharpens neural population tuning via feedback processing in the human visual cortex hierarchy.

    Science.gov (United States)

    Bartsch, Mandy V; Loewe, Kristian; Merkel, Christian; Heinze, Hans-Jochen; Schoenfeld, Mircea A; Tsotsos, John K; Hopf, Jens-Max

    2017-09-25

    Attention can facilitate the selection of elementary object features like color, orientation, or motion. This is referred to as feature-based attention and commonly attributed to a modulation of the gain and tuning of feature-selective units in visual cortex. While gain mechanisms are well characterized, little is known about the cortical processes underlying the sharpening of feature selectivity. Here, we show with high-resolution magnetoencephalography in human observers (men and women) that sharpened selectivity for a particular color arises from feedback processing in the human visual cortex hierarchy. To assess color selectivity, we analyze the response to a color probe that varies in color-distance from an attended color target. We find that attention causes an initial gain enhancement in anterior ventral extrastriate cortex that is coarsely selective for the target color and transitions within ∼100 ms into a sharper tuned profile in more posterior ventral occipital cortex (VO-1/hV4). We conclude that attention sharpens selectivity over time by attenuating the response at lower levels of the cortical hierarchy to color values neighboring the target in color space. These observations support computational models proposing that attention tunes feature selectivity in visual cortex through backward-propagating attenuation of units less tuned to the target.SIGNIFICANCE STATEMENTWhether searching for your car, a particular item of clothing, or just obeying traffic lights, in everyday life we must select items based on color. But how does attention allow us to select a specific color? Here, we use high spatiotemporal resolution neuromagnetic recordings to examine how color selectivity emerges in the human brain. We find that color selectivity evolves as a coarse-to-fine process from higher to lower levels within the visual cortex hierarchy. Our observations support computational models proposing that feature selectivity increases over time, by attenuating the

  5. Hydrogen production by biological processes: a survey of literature

    Energy Technology Data Exchange (ETDEWEB)

    Das, Debabrata [Indian Inst. of Technology, Dept. of Biotechnology, Kharagpur (India); Miami Univ., Clean Energy Research Inst., Coral Gables, FL (United States); Veziroglu, T. Nejat [Miami Univ., Clean Energy Research Inst., Coral Gables, FL (United States)

    2001-07-01

    Hydrogen is the fuel of the future mainly due to its high conversion efficiency, recyclability and nonpolluting nature. Biological hydrogen production processes are found to be more environment friendly and less energy intensive as compared to thermochemical and electrochemical processes. They are mostly controlled by either photosynthetic or fermentative organisms. Till today, more emphasis has been given on the former processes. Nitrogenase and hydrogenase play very important roles. Genetic manipulation of cyanobacteria (hydrogenase negative gene) improves the hydrogen generation. The paper presents a survey of biological hydrogen production processes. The micro-organism and biochemical pathways involved in hydrogen generation processes are presented in some detail. Several developmental works are discussed. Immobilised system is found suitable for the continuous hydrogen production. About 28% of energy can be recovered in the form of hydrogen using sucrose as substrate. Fermentative hydrogen production processes have some edge over the other biological processes. (Author)

  6. The digital pen as a novel device to facilitate the feedback process

    NARCIS (Netherlands)

    van Hell, Elisabeth A.; Kuks, Jan B. M.; Dekker, Martha J.; Borleffs, Jan C. C.; Cohen-Schotanus, Janke

    2011-01-01

    Background: To improve clinical performance assessment, checklist data should be immediately available to students to offer them detailed feedback and be stored in a database for quality assurance purposes. Aim: To introduce the digital pen as clinical performance assessment tool, report examiner sa

  7. Integrating Feedback into Prospective English Language Teachers' Writing Process via Blogs and Portfolios

    Science.gov (United States)

    Arslan, Recep Sahin

    2013-01-01

    The purpose of this study is to investigate the effect of blogging and portfolio keeping on a group of pre-service teachers' writing skill in a compulsory writing course at a tertiary level English language teaching (ELT) programme in Turkey. The study specifically looked into to what extent receiving feedback from course instructor and peers…

  8. Teaching Writing as a Process and Teaching Sentence-Level Syntax: Reformulation as ESL Composition Feedback.

    Science.gov (United States)

    Myers, Sharon

    1997-01-01

    Based on English-as-a-Second-Language (ESL) students' documented preference for error correction and the need for word usage and sentence grammar to become automatic, this article describes the rationale and procedures for using reformulation as composition feedback. The procedures are aimed at improving sentence level grammar. Discusses survey…

  9. Degradation Processes in High-Power Diode Lasers under External Optical Feedback

    DEFF Research Database (Denmark)

    Tomm, Jens. W.; Hempel, Martin; Petersen, Paul Michael;

    2013-01-01

    The effect of moderate external feedback on the gradual degradation of 808 nm emitting AlGaAs-based high-power broad-area diode lasers is analyzed. Eventually the quantum well that actually experiences the highest total optical load remains unaffected by the aging, while severe impact...

  10. Remedial action and feedback processing in a time-estimation task: Evidence for a role of the rostral cingulate zone in behavioral adjustments without learning

    NARCIS (Netherlands)

    Veen, F.M. van der; Röder, C.H.; Mies, G.W.; Lugt, A. van der; Smits, M.

    2011-01-01

    The present study examined the role of the rostral cingulate zone (RCZ) in feedback processing, and especially focused on effects of modality of the feedback stimulus and remedial action. Participants performed a time-estimation task in which they had to estimate a 1-second interval. After the estim

  11. General Purpose Digital Signal Processing VME-Module for 1-Turn Delay Feedback Systems of the CERN Accelerator Chain

    CERN Document Server

    Rossi, V

    2010-01-01

    In the framework of the LHC project and the modifications of the SPS as its injector, the concept has been developed of a global digital signal processing unit (DSPU) that implements in numerical form the architecture of low-level RF systems. Since 2002 a Digital Notch Filter with programmable delay for the SPS Transverse Damper has been fully operational with fixed target and LHC-type beams circulating in the SPS. The approach, using an FPGA as core for the low-level system, is very flexible and allows the upgrade of the signal processing by modification of the original firmware. The development for the LHC 1-Turn delay Feedback has benefited from the same methodology and similar technology. The achieved performances of the LHC 1-Turn delay Feedback are compared with project requirements. The project flow for the recent LHC 1-T Feedback allows synergy with several other applications. The CERN PS Transverse Damper DSPU, with automatic delay compensation adapting the loop delay to the time of flight of the par...

  12. Experimental and Theoretical Studies of Ice-Albedo Feedback Processes in the Arctic Basin

    Science.gov (United States)

    2016-06-07

    collectively make up the ice-albedo feedback mechanism. OBJECTIVES To achieve this goal, we must first determine how shortwave radiation is distributed...information if it does not display a currently valid OMB control number. 1. REPORT DATE 30 SEP 1999 2. REPORT TYPE 3. DATES COVERED 00-00-1999...surface temperature, and surface reflectivity (Figure 1). Significant findings to date include: 1. Changes in albedo are a combination of a gradual

  13. Formal concept analysis in knowledge processing: a survey on applications.

    OpenAIRE

    Poelmans, Jonas; Ignatov, D.; Kuznetsov, S.; Dedene, Guido

    2013-01-01

    This is the second part of a large survey paper in which we analyze recent literature on Formal Concept Analysis (FCA) and some closely related disciplines using FCA. We collected 1072 papers published between 2003 and 2011 mentioning terms related to Formal Concept Analysis in the title, abstract and keywords. We developed a knowledge browsing environment to support our literature analysis process. We use the visualization capabilities of FCA to explore the literature, to discover and concep...

  14. On the relationship between learning strategy and feedback processing in the weather prediction task--Evidence from event-related potentials.

    Science.gov (United States)

    Rustemeier, Martina; Schwabe, Lars; Bellebaum, Christian

    2013-03-01

    Previous work has shown that both declarative and non-declarative strategies can be engaged in probabilistic classification learning. With respect to the neural correlates of these strategies, earlier studies have focused on the classification process itself. In the present experiment, we asked whether the feedback for classification performance is processed differently by declarative and non-declarative learners. We recorded event-related potentials (ERPs) while participants performed a modified version of the weather prediction task, a well-known probabilistic classification learning task. ERP analysis focused on two ERP components typically associated with feedback processing, the feedback-related negativity (FRN) and the P300. FRN amplitude was not affected by learning strategy. The P300, however, was more pronounced in declarative learners, particularly at frontal electrode site Fz. In addition, P300 topography was different in declarative learners, with amplitude differences between negative and positive feedback being more pronounced over the frontal than the parietal cortex. Differences in feedback processing between groups were still seen after declarative learners had switched to a non-declarative strategy in later phases of the task. Our findings provide evidence for different neural mechanisms of feedback processing in declarative and non-declarative learning. This difference emerges at later stages of feedback processing, after the typical time window of the FRN.

  15. Constraints on Feedback Processes during the Formation of Early-type Galaxies

    Science.gov (United States)

    Trevisan, M.; Ferreras, I.; de La Rosa, I. G.; La Barbera, F.; de Carvalho, R. R.

    2012-06-01

    Galaxies are found to obey scaling relations between a number of observables. These relations follow different trends at the low- and high-mass ends. The processes driving the curvature of scaling relations remain uncertain. In this Letter, we focus on the specific family of early-type galaxies, deriving the star formation histories of a complete sample of visually classified galaxies from Sloan Digital Sky Survey DR7 over the redshift range 0.01 < z < 0.025, covering a stellar mass interval from 109 to 3 × 1011 M ⊙. Our sample features the characteristic "knee" in the surface brightness versus mass distribution at M sstarf ~ 3 × 1010 M ⊙ . We find a clear difference between the age and metallicity distributions of the stellar populations above and beyond this knee, which suggests a sudden transition from a constant, highly efficient mode of star formation in high-mass galaxies, gradually decreasing toward the low-mass end of the sample. At fixed mass, our early-type sample is more efficient in building up the stellar content at early times in comparison to the general population of galaxies, with half of the stars already in place by redshift z ~ 2 for all masses. The metallicity-age trend in low-mass galaxies is not compatible with infall of metal-poor gas, suggesting instead an outflow-driven relation.

  16. CONSTRAINTS ON FEEDBACK PROCESSES DURING THE FORMATION OF EARLY-TYPE GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Trevisan, M. [Departamento de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo/IAG, Sao Paulo (Brazil); Ferreras, I. [MSSL, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT (United Kingdom); De La Rosa, I. G. [Instituto de Astrofisica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); La Barbera, F. [INAF-Osservatorio Astronomico di Capodimonte, Napoli (Italy); De Carvalho, R. R., E-mail: trevisan@astro.iag.usp.br [Instituto Nacional de Pesquisas Espaciais/MCT, S. J. dos Campos (Brazil)

    2012-06-20

    Galaxies are found to obey scaling relations between a number of observables. These relations follow different trends at the low- and high-mass ends. The processes driving the curvature of scaling relations remain uncertain. In this Letter, we focus on the specific family of early-type galaxies, deriving the star formation histories of a complete sample of visually classified galaxies from Sloan Digital Sky Survey DR7 over the redshift range 0.01 < z < 0.025, covering a stellar mass interval from 10{sup 9} to 3 Multiplication-Sign 10{sup 11} M{sub Sun }. Our sample features the characteristic 'knee' in the surface brightness versus mass distribution at M{sub *} {approx} 3 Multiplication-Sign 10{sup 10} M{sub Sun} . We find a clear difference between the age and metallicity distributions of the stellar populations above and beyond this knee, which suggests a sudden transition from a constant, highly efficient mode of star formation in high-mass galaxies, gradually decreasing toward the low-mass end of the sample. At fixed mass, our early-type sample is more efficient in building up the stellar content at early times in comparison to the general population of galaxies, with half of the stars already in place by redshift z {approx} 2 for all masses. The metallicity-age trend in low-mass galaxies is not compatible with infall of metal-poor gas, suggesting instead an outflow-driven relation.

  17. Developing Sustainable Feedback Practices

    Science.gov (United States)

    Carless, David; Salter, Diane; Yang, Min; Lam, Joy

    2011-01-01

    Feedback is central to the development of student learning, but within the constraints of modularized learning in higher education it is increasingly difficult to handle effectively. This article makes a case for sustainable feedback as a contribution to the reconceptualization of feedback processes. The data derive from the Student Assessment and…

  18. Feedbacks between vegetation and solifluction processes on hillslopes: a case study of an alpine turf-banked solifluction lobe

    Science.gov (United States)

    Eichel, Jana; Draebing, Daniel; Wieland, Markus; Eling, Christian; Klingbeil, Lasse; Dikau, Richard

    2015-04-01

    Solifluction is one of the most widespread processes transporting soil on hillslopes in periglacial environments. While periglacial geomorphologists identified climatic and soil parameters as most important factors influencing solifluction, ecologist have long recognized the importance of vegetation and the co-occurrence of certain species and vegetation communities with solifluction processes and landforms. However, the mechanism of vegetation influences on solifluction, as well as feedbacks between solifluction processes and vegetation, which result in specific vegetation organization and specific landforms, e.g., turf-banked solifluction lobes, is only partly understood. The aim of our study is to improve the understanding of feedbacks between vegetation and solifluction processes and landforms by using established and up-to-date methods in a detailed small-scale study on a turf-banked solifluction lobe in the Turtmann glacier forefield (Switzerland). Our objectives are (i) to examine the effects of species composition and vegetation organization on landform properties; (ii) to investigate the effects of landform properties on species composition and vegetation organization and (iii) to evaluate if feedbacks create turf-banked solifluction lobes as biogeomorphic structures. To assess solifluction lobe and vegetation properties, we employed a detailed geomorphic and vegetation mapping (1:50), complemented by an UAV derived high-resolution orthophoto and DEM, and 2D and 3D electrical resistivity tomography (ERT) measurements in combination with soil moisture measurements. Vegetation mapping shows that (i) dwarf shrubs, which through their plant functional traits can act as engineer species, are the main species covering the solifluction lobe. Geomorphic mapping, DEM terrain analyses and 3D ERT indicate that (ii) lobe geomorphometry and material properties (grain size, moisture) strongly influence species distribution and diversity. 2D ERT shows permafrost

  19. Data Processing Factory for the Sloan Digital Sky Survey

    Science.gov (United States)

    Stoughton, Christopher; Adelman, Jennifer; Annis, James T.; Hendry, John; Inkmann, John; Jester, Sebastian; Kent, Steven M.; Kuropatkin, Nickolai; Lee, Brian; Lin, Huan; Peoples, John, Jr.; Sparks, Robert; Tucker, Douglas; Vanden Berk, Dan; Yanny, Brian; Yocum, Dan

    2002-12-01

    The Sloan Digital Sky Survey (SDSS) data handling presents two challenges: large data volume and timely production of spectroscopic plates from imaging data. A data processing factory, using technologies both old and new, handles this flow. Distribution to end users is via disk farms, to serve corrected images and calibrated spectra, and a database, to efficiently process catalog queries. For distribution of modest amounts of data from Apache Point Observatory to Fermilab, scripts use rsync to update files, while larger data transfers are accomplished by shipping magnetic tapes commercially. All data processing pipelines are wrapped in scripts to address consecutive phases: preparation, submission, checking, and quality control. We constructed the factory by chaining these pipelines together while using an operational database to hold processed imaging catalogs. The science database catalogs all imaging and spectroscopic object, with pointers to the various external files associated with them. Diverse computing systems address particular processing phases. UNIX computers handle tape reading and writing, as well as calibration steps that require access to a large amount of data with relatively modest computational demands. Commodity CPUs process steps that require access to a limited amount of data with more demanding computations requirements. Disk servers optimized for cost per Gbyte serve terabytes of processed data, while servers optimized for disk read speed run SQLServer software to process queries on the catalogs. This factory produced data for the SDSS Early Data Release in June 2001, and it is currently producing Data Release One, scheduled for January 2003.

  20. Limitations of Feedback, Feedforward and IMC Controller for a First Order Non-Linear Process with Dead Time

    Directory of Open Access Journals (Sweden)

    Maruthai Suresh

    2010-10-01

    Full Text Available A nonlinear process, the heat exchanger whose parameters vary with respect to the process variable, is considered. The time constant and gain of the chosen process vary as a function of temperature. The limitations of the conventional feedback controller tuned using Ziegler-Nichols settings for the chosen process are brought out. The servo and regulatory responses through simulation and experimentation for various magnitudes of set-point changes and load changes at various operating points with the controller tuned only at a chosen nominal operating point are obtained and analyzed. Regulatory responses for output load changes are studied. The efficiency of feedforward controller and the effects of modeling error have been brought out. An IMC based system is presented to understand clearly how variations of system parameters affect the performance of the controller. The present work illustrates the effectiveness of Feedforward and IMC controller.

  1. Ammonia-based feedforward and feedback aeration control in activated sludge processes.

    Science.gov (United States)

    Rieger, Leiv; Jones, Richard M; Dold, Peter L; Bott, Charles B

    2014-01-01

    Aeration control at wastewater treatment plants based on ammonia as the controlled variable is applied for one of two reasons: (1) to reduce aeration costs, or (2) to reduce peaks in effluent ammonia. Aeration limitation has proven to result in significant energy savings, may reduce external carbon addition, and can improve denitrification and biological phosphorus (bio-P) performance. Ammonia control for limiting aeration has been based mainly on feedback control to constrain complete nitrification by maintaining approximately one to two milligrams of nitrogen per liter of ammonia in the effluent. Increased attention has been given to feedforward ammonia control, where aeration control is based on monitoring influent ammonia load. Typically, the intent is to anticipate the impact of sudden load changes, and thereby reduce effluent ammonia peaks. This paper evaluates the fundamentals of ammonia control with a primary focus on feedforward control concepts. A case study discussion is presented that reviews different ammonia-based control approaches. In most instances, feedback control meets the objectives for both aeration limitation and containment of effluent ammonia peaks. Feedforward control, applied specifically for switching aeration on or off in swing zones, can be beneficial when the plant encounters particularly unusual influent disturbances.

  2. Gemini NIFS survey of feeding and feedback processes in nearby active galaxies - I. Stellar kinematics

    Science.gov (United States)

    Riffel, Rogemar A.; Storchi-Bergmann, Thaisa; Riffel, Rogerio; Dahmer-Hahn, Luis G.; Diniz, Marlon R.; Schönell, Astor J.; Dametto, Natacha Z.

    2017-09-01

    We use the Gemini Near-Infrared Integral Field Spectrograph (NIFS) to map the stellar kinematics of the inner few hundred parsecs of a sample of 16 nearby Seyfert galaxies, at a spatial resolution of tens of parsecs and spectral resolution of 40 km s- 1. We find that the line-of-sight (LOS) velocity fields for most galaxies are well reproduced by rotating disc models. The kinematic position angle (PA) derived for the LOS velocity field is consistent with the large-scale photometric PA. The residual velocities are correlated with the hard X-ray luminosity, suggesting that more luminous active galactic nuclei have a larger impact in the surrounding stellar dynamics. The central velocity dispersion values are usually higher than the rotation velocity amplitude, what we attribute to the strong contribution of bulge kinematics in these inner regions. For 50 per cent of the galaxies, we find an inverse correlation between the velocities and the h3 Gauss-Hermitte moment, implying red wings in the blueshifted side and blue wings in the redshifted side of the velocity field, attributed to the movement of the bulge stars lagging the rotation. Two of the 16 galaxies (NGC 5899 and Mrk 1066) show an S-shape zero velocity line, attributed to the gravitational potential of a nuclear bar. Velocity dispersion (σ) maps show rings of low-σ values (˜50-80 km s- 1) for four objects and `patches' of low σ for six galaxies at 150-250 pc from the nucleus, attributed to young/ intermediate age stellar populations.

  3. Using Automated Processes to Generate Test Items And Their Associated Solutions and Rationales to Support Formative Feedback

    Directory of Open Access Journals (Sweden)

    Mark Gierl

    2015-08-01

    Full Text Available Automatic item generation is the process of using item models to produce assessment tasks using computer technology. An item model is similar to a template that highlights the elements in the task that must be manipulated to produce new items. The purpose of our study is to describe an innovative method for generating large numbers of diverse and heterogeneous items along with their solutions and associated rationales to support formative feedback. We demonstrate the method by generating items in two diverse content areas, mathematics and nonverbal reasoning

  4. A survey of decontamination processes applicable to DOE nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L.; Chamberlain, D.B.; Conner, C.; Vandegrift, G.F.

    1997-05-01

    The objective of this survey was to select an appropriate technology for in situ decontamination of equipment interiors as part of the decommissioning of U.S. Department of Energy nuclear facilities. This selection depends on knowledge of existing chemical decontamination methods. This report provides an up-to-date review of chemical decontamination methods. According to available information, aqueous systems are probably the most universally used method for decontaminating and cleaning metal surfaces. We have subdivided the technologies, on the basis of the types of chemical solvents, into acid, alkaline permanganate, highly oxidizing, peroxide, and miscellaneous systems. Two miscellaneous chemical decontamination methods (electrochemical processes and foam and gel systems) are also described. A concise technical description of various processes is given, and the report also outlines technical considerations in the choice of technologies, including decontamination effectiveness, waste handing, fields of application, and the advantages and limitations in application. On the basis of this survey, six processes were identified for further evaluation. 144 refs., 2 tabs.

  5. Contrasting the eastern Pacific El Niño and the central Pacific El Niño: process-based feedback attribution

    Science.gov (United States)

    Hu, Xiaoming; Yang, Song; Cai, Ming

    2016-10-01

    This paper examines the roles of radiative and non-radiative air-sea coupled thermodynamic processes in modifying sea surface temperature (SST) anomalies driven by (air-sea coupled) oceanic dynamic processes, focusing on their contributions to the key differences between the eastern Pacific (EP) El Niño and the central Pacific (CP) El Niño. The attribution is achieved by decomposing SST anomalies into partial temperature anomalies due to individual processes using a coupled atmosphere-surface climate feedback-response analysis method. Oceanic processes induce warming from the central to the eastern equatorial Pacific and cooling over the western basin with a maximum warming center in the central Pacific for both types of El Niño. The processes that act to oppose the oceanic process-induced SST anomalies are surface latent heat flux, sensible heat flux, cloud, and atmospheric dynamic feedbacks, referred to as negative-feedback processes. The cooling due to each of the four negative-feedback processes is the strongest in the region where the initial warming due to oceanic processes is the largest. Water-vapor feedback is the sole process that acts to enhance the initial warming induced by oceanic processes. The increase in atmospheric water vapor over the eastern Pacific is much stronger for the EP El Niño than for the CP El Niño. It is the strong water-vapor feedback over the eastern Pacific and the strong negative feedbacks over the central equatorial Pacific that help to relocate the maximum warming center from the central Pacific to the eastern basin for the EP El Niño.

  6. Time-fractional derivatives in relaxation processes: a tutorial survey

    CERN Document Server

    Mainardi, Francesco

    2008-01-01

    The aim of this tutorial survey is to revisit the basic theory of relaxation processes governed by linear differential equations of fractional order. The fractional derivatives are intended both in the Rieamann-Liouville sense and in the Caputo sense. After giving a necessary outline of the classical theory of linear viscoelasticity, we contrast these two types of fractional derivatives in their ability to take into account initial conditions in the constitutive equations of fractional order. We also provide historical notes on the origins of the Caputo derivative and on the use of fractional calculus in viscoelasticity.

  7. Stochastic processes and feedback-linearisation for online identification and Bayesian adaptive control of fully-actuated mechanical systems

    CERN Document Server

    Calliess, Jan-Peter; Roberts, Stephen J

    2013-01-01

    This work proposes a new method for simultaneous probabilistic identification and control of an observable, fully-actuated mechanical system. Identification is achieved by conditioning stochastic process priors on observations of configurations and noisy estimates of configuration derivatives. In contrast to previous work that has used stochastic processes for identification, we leverage the structural knowledge afforded by Lagrangian mechanics and learn the drift and control input matrix functions of the control-affine system separately. We utilise feedback-linearisation to reduce, in expectation, the uncertain nonlinear control problem to one that is easy to regulate in a desired manner. Thereby, our method combines the flexibility of nonparametric Bayesian learning with epistemological guarantees on the expected closed-loop trajectory. We illustrate our method in the context of torque-actuated pendula where the dynamics are learned with a combination of normal and log-normal processes.

  8. The Analysis and Modeling of The Profitability Feedback Process – A Dynamic Model on Portugal’s National Economy

    Directory of Open Access Journals (Sweden)

    Bianca-Ioana Popescu

    2015-06-01

    Full Text Available The aim of the present paper is to underline the influence of the profitability process at macroe-conomic level will exert on real economy. Until now relevant literature has been focused on firms, banks and industries but only with the objective of comparing past profitability of the studied entity or comparison to other competitors on the market and with microfoundation calculus - profitability being calculated for a panel of firms in the studied industry. The model of the Profitability Feedback Process is capable of surprising the influences the concept of profitability will have at macroeconomic level as being considered to be one of the auto-regulation processes of a national economy. The simulations have been made on EUROSTAT’s official stats of Portugal between 2005 and 2012 annual data and the simulations have revealed robust behavior of the system in relation to the profitability and the economic context and sustain the rationality of our attempt.

  9. A SURVEY OF SKYLINE PROCESSING IN VARIOUS ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Angel C Bency

    2014-03-01

    Full Text Available Skyline queries which received an interesting attention to the database and data mining field and its main advantage is it is used for multi-criteria decision making. Advanced query operators, such as skyline queries are necessary in order to help users to handle huge amount of data from a large database by identifying set of non-dominated points. Skyline queries means it retrieve set of non-dominated points or better points from the given data points. It provides an interactive environment for information retrieval that help user to get answer for the given preference based query. This survey paper discusses about various skyline query processing algorithms and its different application in various fields includes spatial database, subspace, network, distributed environment etc. This study gives an overview about the existing algorithms for skyline query processing technique and different applications.

  10. Supervisor Feedback.

    Science.gov (United States)

    Hayman, Marilyn J.

    1981-01-01

    Investigated the effectiveness of supervisor feedback in contributing to learning counseling skills. Counselor trainees (N=64) were assigned to supervisor feedback, no supervisor feedback, or control groups for three training sessions. Results indicated counseling skills were learned best by students with no supervisor feedback but self and peer…

  11. A Study on Direct Feedback and Indirect Feedback in Graduate Students ’Writing

    Institute of Scientific and Technical Information of China (English)

    张志国

    2014-01-01

    Feedback plays a central role in writing development. However correcting students’writing is one of the most time-consuming tasks for our senior English teachers. By conducting a survey of direct feedback and indirect feedback in students writ⁃ing the author tries to test the influence of direct feedback and indirect feedback in graduates ’writing.

  12. Investigation of transient processes at the DELTA electron storage ring using a digital bunch-by-bunch feedback system

    Energy Technology Data Exchange (ETDEWEB)

    Hoener, Markus

    2015-07-01

    At the 1.5-GeV synchrotron radiation source DELTA, operated by the TU Dortmund University, intensive synchrotron radiation in the spectral range from hard X-rays to THz radiation is generated by the circular deflection of highly relativistic electron bunches. Interacting with the vacuum chamber wall, the electron bunches create electric fields, which can act back on subsequent bunches. With increasing beam current, the excitation is enhanced so that the electron beam is unstable, which means that the electron bunches oscillate longitudinally or transversely relative to their reference position. The oscillations reduce the quality of the synchrotron radiation and limit the maximum storable beam current. Within the scope of this thesis, the beam instabilities at the storage ring were systematically investigated. A digital bunch-by-bunch feedback system was installed and commissioned, which allows to detect and digitize the position of each electron bunch at each turn. Based on the input signal, a correction signal is calculated in order to suppress transverse and longitudinal oscillation of the bunches. In addition, it is possible to excite dedicated bunches. The systematic excitation of all coupled-bunch modes allowed for the first time to determine the damping rates of all 192 eigenmodes of the electron beam. The current dependence of the damping rates was investigated and an instability threshold was found. Besides the investigation of multibunch instabilities, single-bunch instabilities are discussed. In addition, the acquisition unit of the digital feedback system can be triggered on external events. This was used to investigate the injection process and beam losses. It was shown that the transverse feedback system increases the injection efficiency. Another aspect of this thesis is the improvement of the signal quality of ultrashort coherent synchrotron radiation pulses, which are generated by the short-pulse facility at DELTA. The short-pulse facility is based

  13. An Evaluation of an Internal Audit on Student Feedback within a British University: A Quality Enhancement Process

    Science.gov (United States)

    Reid, Ken

    2010-01-01

    Purpose: Final year students attending British universities now complete an annual questionnaire to assess their views on their learning experiences of higher education (HE) from a variety of perspectives. They undertake this process as part of the National Student Survey (NSS). These data are then collated and an annual report with associated…

  14. An Evaluation of an Internal Audit on Student Feedback within a British University: A Quality Enhancement Process

    Science.gov (United States)

    Reid, Ken

    2010-01-01

    Purpose: Final year students attending British universities now complete an annual questionnaire to assess their views on their learning experiences of higher education (HE) from a variety of perspectives. They undertake this process as part of the National Student Survey (NSS). These data are then collated and an annual report with associated…

  15. Algal Feedback and Removal Efficiency in a Sequencing Batch Reactor Algae Process (SBAR to Treat the Antibiotic Cefradine.

    Directory of Open Access Journals (Sweden)

    Jianqiu Chen

    Full Text Available Many previous studies focused on the removal capability for contaminants when the algae grown in an unexposed, unpolluted environment and ignored whether the feedback of algae to the toxic stress influenced the removal capability in a subsequent treatment batch. The present research investigated and compared algal feedback and removal efficiency in a sequencing batch reactor algae process (SBAR to remove cefradine. Three varied pollution load conditions (10, 30 and 60 mg/L were considered. Compared with the algal characteristics in the first treatment batch at 10 and 30 mg/L, higher algal growth inhibition rates were observed in the second treatment batch (11.23% to 20.81%. In contrast, algae produced more photosynthetic pigments in response to cefradine in the second treatment batch. A better removal efficiency (76.02% was obtained during 96 h when the alga treated the antibiotic at 60 mg/L in the first treatment batch and at 30 mg/L in the second treatment batch. Additionally, the removal rate per unit algal density was also improved when the alga treated the antibiotic at 30 or 60 mg/L in the first treatment batch, respectively and at 30 mg/L in the second treatment batch. Our result indicated that the green algae were also able to adapt to varied pollution loads in different treatment batches.

  16. The VLT-FLAMES Tarantula Survey - XI. A census of the hot luminous stars and their feedback in 30 Doradus

    CERN Document Server

    Doran, E I; de Koter, A; Evans, C J; McEvoy, C; Walborn, N R; Bastian, N; Bestenlehner, J M; Grafener, G; Herrero, A; Kohler, K; Apellaniz, J Maiz; Najarro, F; Puls, J; Sana, H; Schneider, F R N; Taylor, W D; van Loon, J Th; Vink, J S

    2013-01-01

    We compile the first comprehensive census of hot luminous stars in the 30 Doradus (30 Dor) star forming region of the LMC. The census extends to a radius of 10arcmin (150pc) from the central cluster, R136. Stars were selected photometrically and combined with the latest spectral types. 1145 candidate hot luminous stars were identified of which >700 were considered genuine early type stars that contribute to feedback. We assess the spectroscopic completeness to be 85% in outer regions (>5pc) but fall to 35% in the vicinity of R136, giving a total of 500 hot luminous stars with spectroscopy. Stellar calibrations and models were used to obtain their physical parameters before integrated values were compared to global observations and the population synthesis code, Starburst99. The 31 W-R and Of/WN stars made large contributions to the total ionising and wind luminosities of ~40% and ~50%, respectively. Stars with Minit>100Msun also showed high contributions to the global feedback, ~25% in both cases. Such massiv...

  17. On oscillation reduction in feedback control for processes with an uncertain dead time and internal-external disturbances.

    Science.gov (United States)

    Zhang, Yuqiong; Li, Donghai; Gao, Zhiqiang; Zheng, Qinling

    2015-11-01

    This paper aims to find a practical solution to reduce oscillation on the Smith Predictor (SP) based design with the dead time (DT) uncertainty, making it less sensitive to DT change and more effective in disturbance rejection. First, a conditional feedback mechanism is introduced in SP to reduce the amount of oscillation caused by the model inaccuracies in the DT parameter. Then, to address the oscillation caused by the phase lag in traditional PI controller and uncertain dynamics, this conditional SP is combined with active disturbance rejection control (ADRC), assisted by the knowledge of process dynamics. A practical tuning method is provided for the practicing engineers. The proposed approach is validated in extensive simulation studies with different types of plants and in frequency domain analysis. The simulation results show significant improvements in performance robustness and transient response.

  18. Processing of sub- and supra-second intervals in the primate brain results from the calibration of neuronal oscillators via sensory, motor and feedback processes

    Directory of Open Access Journals (Sweden)

    Daya Shankar Gupta

    2014-08-01

    Full Text Available The processing of time intervals in the sub- to supra-second range by the brain is critical for the interaction of primates with their surroundings in activities, such as foraging and hunting. For an accurate processing of time intervals by the brain, representation of the physical time within neuronal circuits is necessary. I propose that time-dimension of the physical surrounding is represented in the brain by different types of neuronal oscillators, generating spikes or spike bursts at regular intervals. The proposed oscillators include the pacemaker neurons, tonic inputs and synchronized excitation and inhibition of inter-connected neurons. Oscillators, which are built inside various circuits of brain, help to form modular clocks, processing time intervals or other temporal characteristics specific to functions of a circuit. Relative or absolute duration is represented within neuronal oscillators by ‘neural temporal unit’, defined as the interval between regularly occurring spikes or spike bursts. Oscillator output is processed to produce changes in activities of neurons, named frequency modulator neuron, wired within a separate module, represented by the rate of change in frequency, and frequency of activities, proposed to encode time intervals. Inbuilt oscillators are calibrated by (a feedback processes (b input of time intervals resulting from rhythmic external sensory stimulation and (c synchronous effects of feedback processes and evoked sensory activity. A single active clock is proposed per circuit, which is calibrated by one or more mechanisms. Multiple calibration mechanisms, inbuilt oscillators and the presence of modular connections prevent a complete loss of interval timing functions of the brain.

  19. Initiatives to improve feedback culture in the final year of a veterinary program.

    Science.gov (United States)

    Warman, Sheena M; Laws, Emma J; Crowther, Emma; Baillie, Sarah

    2014-01-01

    Despite the recognized importance of feedback in education, student satisfaction with the feedback process in medical and veterinary programs is often disappointing. We undertook various initiatives to try to improve the feedback culture in the final clinical year of the veterinary program at the University of Bristol, focusing on formative verbal feedback. The initiatives included E-mailed guidelines to staff and students, a faculty development workshop, and a reflective portfolio task for students. Following these initiatives, staff and students were surveyed regarding their perceptions of formative feedback in clinical rotations, and focus groups were held to further explore issues. The amount of feedback appeared to have increased, along with improved recognition of feedback by students and increased staff confidence and competence in the process. Other themes that emerged included inconsistencies in feedback among staff and between rotations; difficulties with giving verbal feedback to students, particularly when it relates to professionalism; the consequences of feedback for both staff and students; changes and challenges in students' feedback-seeking behavior; and the difficulties in providing accurate, personal end-of-rotation assessments. This project has helped improve the feedback culture within our clinics; the importance of sustaining and further developing the feedback culture is discussed in this article.

  20. Experimental and Theoretical Studies of Ice-Albedo Feedback Processes in the Arctic Basin

    Science.gov (United States)

    2016-06-14

    more. Instruments flown on various flights included: an aerial mapping camera, video camera, spectral radiometer, infrared thermometer, digital ... competing processes involving brine pocket enlargement and merging in warm ice that severely reduces temperature-dependent changes in the amount of

  1. Beowulf Distributed Processing and the United States Geological Survey

    Science.gov (United States)

    Maddox, Brian G.

    2002-01-01

    Introduction In recent years, the United States Geological Survey's (USGS) National Mapping Discipline (NMD) has expanded its scientific and research activities. Work is being conducted in areas such as emergency response research, scientific visualization, urban prediction, and other simulation activities. Custom-produced digital data have become essential for these types of activities. High-resolution, remotely sensed datasets are also seeing increased use. Unfortunately, the NMD is also finding that it lacks the resources required to perform some of these activities. Many of these projects require large amounts of computer processing resources. Complex urban-prediction simulations, for example, involve large amounts of processor-intensive calculations on large amounts of input data. This project was undertaken to learn and understand the concepts of distributed processing. Experience was needed in developing these types of applications. The idea was that this type of technology could significantly aid the needs of the NMD scientific and research programs. Porting a numerically intensive application currently being used by an NMD science program to run in a distributed fashion would demonstrate the usefulness of this technology. There are several benefits that this type of technology can bring to the USGS's research programs. Projects can be performed that were previously impossible due to a lack of computing resources. Other projects can be performed on a larger scale than previously possible. For example, distributed processing can enable urban dynamics research to perform simulations on larger areas without making huge sacrifices in resolution. The processing can also be done in a more reasonable amount of time than with traditional single-threaded methods (a scaled version of Chester County, Pennsylvania, took about fifty days to finish its first calibration phase with a single-threaded program). This paper has several goals regarding distributed processing

  2. Evaluating the role of reentrant output-to-input feedback in simultaneous pattern processing

    Energy Technology Data Exchange (ETDEWEB)

    Achler, Tsvi [Los Alamos National Laboratory

    2010-01-01

    Simultaneous Pattern Processing (SPP) is defined as the ability to identify simultaneous-intermixed patterns without isolating them individually (e.g. without separating each pattern in space and processing it individually). Enhanced SPP ability is beneficial for many real-life applications such as scene understanding, separating simultaneous voices, and identifying odorant or taste mixes. The first part of this work identifies how SPP scenarios are problematic to models which train synaptic connections or implement lateral inhibition and quantifies how subtle difficulties lead to complex combinatorial issues. The second part of this work proposes and tests an algorithm motivated by Ubiquitous re-entrant 'output to input' connections found throughout sensory processing regions of the brain. Through these connections the model proposes a dynamic gain mechanism that can provide functionality normally achieved through variable synaptic connections. The re-entrant structure combined with enhanced perfonnance suggests the brain may utilize this configuration for SPP flexibility.

  3. On the Cluster Physics of Sunyaev-Zel'dovich Surveys I: The Influence of Feedback, Non-thermal Pressure and Cluster Shapes on Y-M Scaling Relations

    CERN Document Server

    Battaglia, N; Pfrommer, C; Sievers, J L

    2011-01-01

    The utility of large Sunyaev Zel'dovich (SZ) surveys for determining cosmological parameters from cluster abundances is limited by the theoretical uncertainties in the integrated SZ-flux-to-mass relation, Y-M. We explore how non-thermal pressure and the anisotropic shape of the gas distribution of the intracluster medium (ICM) impacts Y-M scaling using a suite of SPH simulations of the cosmic web. We contrast results for models with different treatments of entropy injection and transport, varying radiative cooling, star formation and accompanying supernova feedback, cosmic rays, and energetic feedback from active galactic nuclei (AGN). We find that the gas kinetic-to-thermal pressure ratio from internal bulk motions depends on the cluster mass, and increases in the outer-cluster due to enhanced substructure, as does the asphericity of the ICM gas. With only a ~5-10% correction to projected (observable) ellipticities, we can infer the 3D ellipticities. Our simulated Y-M-slope roughly follows the self-similar p...

  4. Evolution of BCGs structural parameters in the last $\\sim$6 Gyr: feedback processes versus merger events

    CERN Document Server

    Ascaso, B; Varela, J; Cava, A; Bettoni, D; Moles, M; D'Onofrio, M

    2010-01-01

    We present results on the evolution in the last 6 Gyr of the structural parameters of two samples of brightest cluster galaxies (BCGs). The nearby sample of BCGs consist on 69 galaxies from the WINGS survey spanning a redshift range of 0.04$<$z$<$0.07. The intermediate redshift (0.3$<$z$<$0.6) sample is formed by 20 BCGs extracted from the Hubble Space Telescope archive. Both samples have similar spatial resolution and their host clusters have similar X-ray luminosities. We report an increase in the size of the BCGs from intermediate to local redshift. However, we do not detect any variation in the S\\'ersic shape parameter in both samples. These results are proved to be robust since the observed tendencies are model independent. We also obtain significant correlations between some of the BCGs parameters and the main properties of the host clusters. More luminous, larger and centrally located BCGs are located in more massive and dominant galaxy clusters. These facts indicate that the host galaxy cl...

  5. Linking Failure Feedback to Individual Creativity: The Moderation Role of Goal Orientation

    Science.gov (United States)

    He, Yimin; Yao, Xiang; Wang, Shuhong; Caughron, Jay

    2016-01-01

    The sense-making theory of creativity is extended by identifying failure feedback as a process that shapes creative interpretations and actions. We also consider the moderating effect of goal orientation on the relationship between failure feedback and individual creativity, according to the sense-making theory. A 2-waves survey data from…

  6. Linking Failure Feedback to Individual Creativity: The Moderation Role of Goal Orientation

    Science.gov (United States)

    He, Yimin; Yao, Xiang; Wang, Shuhong; Caughron, Jay

    2016-01-01

    The sense-making theory of creativity is extended by identifying failure feedback as a process that shapes creative interpretations and actions. We also consider the moderating effect of goal orientation on the relationship between failure feedback and individual creativity, according to the sense-making theory. A 2-waves survey data from…

  7. Healthy Change Processes-A Diary Study of Five Organizational Units. Establishing a Healthy Change Feedback Loop.

    Science.gov (United States)

    Lien, Mathilde; Saksvik, Per Øystein

    2016-10-01

    This paper explores a change process in the Central Norway Regional Health Authority that was brought about by the implementation of a new economics and logistics system. The purpose of this paper is to contribute to understanding of how employees' attitudes towards change develop over time and how attitudes differ between the five health trusts under this authority. In this paper, we argue that a process-oriented focus through a longitudinal diary method, in addition to action research and feedback loops, will provide greater understanding of the evaluation of organizational change and interventions. This is explored through the assumption that different units will have different perspectives and attitudes towards the same intervention over time because of different contextual and time-related factors. The diary method aims to capture the context, events, reflections and interactions when they occur and allows for a nuanced frame of reference for the different phases of the implementation process and how these phases are perceived by employees. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. FUNDAMENTALS OF THE ANALYTIC NETWORK PROCESS - DEPENDENCE AND FEEDBACK IN DECISION-MAKING WITH A SINGLE NETWORK

    Institute of Scientific and Technical Information of China (English)

    Thomas L.SAATY

    2004-01-01

    The Analytic Network Process (ANP) is a multicriteria theory of measurement used to derive relative priority scales of absolute numbers from individual judgments (or from actual measurements normalized to a relative form) that also belong to a fundamental scale of absolute numbers. These judgments represent the relative influence, of one of two elements over the other in a pairwise comparison process on a third element in the system, with respect to an underlying control criterion.Through its supermatrix, whose entries are themselves rratrices of column priorities, the ANP synthesizes the outcome of dependence and feedback within and between clusters of elements. The Analytic Hierarchy Process (AHP) with its independence assumptions on upper levels from lower levels and the independence of the elements in a level is a special case of the ANP. The ANP is an essential tool for articulating our understanding of a decision problem. One had to overcome the limitation of linear hierarchic structures and their mathematical consequences. This part on the ANP summarizes and illustrates the basic concepts of the ANP and shows how informed intuitive judgments can lead to real life answers that are matched by actual measurements in the real world (for example, relative dollar values) as illustrated in market share examples that rely on judgments and not on numerical data.

  9. Modeling of hydroecological feedbacks predicts distinct classes of landscape pattern, process, and restoration potential in shallow aquatic ecosystems

    Science.gov (United States)

    Larsen, Laurel G.; Harvey, Judson W.

    2011-01-01

    It is widely recognized that interactions between vegetation and flow cause the emergence of channel patterns that are distinct from the standard Schumm classification of river channels. Although landscape pattern is known to be linked to ecosystem services such as habitat provision, pollutant removal, and sustaining biodiversity, the mechanisms responsible for the development and stability of different landscape patterns in shallow, vegetated flows have remained poorly understood. Fortunately, recent advances have made possible large-scale models of flow through vegetated environments that can be run over a range of environmental variables and over timescales of millennia. We describe a new, quasi-3D cellular automata model that couples simulations of shallow-water flow, bed shear stresses, sediment transport, and vegetation dynamics in an efficient manner. That efficiency allowed us to apply the model widely in order to determine how different hydroecological feedbacks control landscape pattern and process in various types of wetlands and floodplains. Distinct classes of landscape pattern were uniquely associated with specific types of allogenic and autogenic drivers in wetland flows. Regular, anisotropically patterned wetlands were dominated by allogenic processes (i.e., processes driven by periodic high water levels and flow velocities that redistribute sediment), relative to autogenic processes (e.g., vegetation production, peat accretion, and gravitational erosion). These anistropically patterned wetlands are therefore particularly prone to hydrologic disturbance. Other classes of wetlands that emerged from simulated interactions included maze-patterned, amorphous, and topographically noisy marshes, open marsh with islands, banded string-pool sequences perpendicular to flow, parallel deep and narrow channels flanked by marsh, and ridge-and-slough patterned marsh oriented parallel to flow. Because vegetation both affects and responds to the balance between the

  10. Feedback processes in cellulose thermal decomposition. Implications for fire-retarding strategies and treatments

    CERN Document Server

    Ball, R; Brindley, J

    2002-01-01

    A simple dynamical system that models the competitive thermokinetics and chemistry of cellulose decomposition is examined, with reference to evidence from experimental studies indicating that char formation is a low activation energy exothermal process and volatilization is a high activation energy endothermal process. The thermohydrolysis chemistry at the core of the primary competition is described. Essentially, the competition is between two nucleophiles, a molecule of water and an -OH group on C_6 of an end glucosyl cation, to form either a reducing chain fragment with the propensity to undergo the bond-forming reactions that ultimately form char or a levoglucosan-end-fragment that depolymerizes to volatile products. The results of this analysis suggest that promotion of char formation under thermal stress can actually increase the production of flammable volatiles. Thus we would like to convey an important safety message in this paper: in some situations where heat and mass transfer is restricted in cell...

  11. Modeling of hydroecological feedbacks predicts distinct classes of landscape pattern, process, and restoration potential in shallow aquatic ecosystems

    Science.gov (United States)

    Larsen, Laurel G.; Harvey, Judson W.

    2011-03-01

    It is widely recognized that interactions between vegetation and flow cause the emergence of channel patterns that are distinct from the standard Schumm classification of river channels. Although landscape pattern is known to be linked to ecosystem services such as habitat provision, pollutant removal, and sustaining biodiversity, the mechanisms responsible for the development and stability of different landscape patterns in shallow, vegetated flows have remained poorly understood. Fortunately, recent advances have made possible large-scale models of flow through vegetated environments that can be run over a range of environmental variables and over timescales of millennia. We describe a new, quasi-3D cellular automata model that couples simulations of shallow-water flow, bed shear stresses, sediment transport, and vegetation dynamics in an efficient manner. That efficiency allowed us to apply the model widely in order to determine how different hydroecological feedbacks control landscape pattern and process in various types of wetlands and floodplains. Distinct classes of landscape pattern were uniquely associated with specific types of allogenic and autogenic drivers in wetland flows. Regular, anisotropically patterned wetlands were dominated by allogenic processes (i.e., processes driven by periodic high water levels and flow velocities that redistribute sediment), relative to autogenic processes (e.g., vegetation production, peat accretion, and gravitational erosion). These anistropically patterned wetlands are therefore particularly prone to hydrologic disturbance. Other classes of wetlands that emerged from simulated interactions included maze-patterned, amorphous, and topographically noisy marshes, open marsh with islands, banded string-pool sequences perpendicular to flow, parallel deep and narrow channels flanked by marsh, and ridge-and-slough patterned marsh oriented parallel to flow. Because vegetation both affects and responds to the balance between the

  12. Survey: interpolation methods for whole slide image processing.

    Science.gov (United States)

    Roszkowiak, L; Korzynska, A; Zak, J; Pijanowska, D; Swiderska-Chadaj, Z; Markiewicz, T

    2017-02-01

    Evaluating whole slide images of histological and cytological samples is used in pathology for diagnostics, grading and prognosis . It is often necessary to rescale whole slide images of a very large size. Image resizing is one of the most common applications of interpolation. We collect the advantages and drawbacks of nine interpolation methods, and as a result of our analysis, we try to select one interpolation method as the preferred solution. To compare the performance of interpolation methods, test images were scaled and then rescaled to the original size using the same algorithm. The modified image was compared to the original image in various aspects. The time needed for calculations and results of quantification performance on modified images were also compared. For evaluation purposes, we used four general test images and 12 specialized biological immunohistochemically stained tissue sample images. The purpose of this survey is to determine which method of interpolation is the best to resize whole slide images, so they can be further processed using quantification methods. As a result, the interpolation method has to be selected depending on the task involving whole slide images.

  13. Open Access Article Processing Charges: DOAJ Survey May 2014

    Directory of Open Access Journals (Sweden)

    Heather Morrison

    2015-02-01

    Full Text Available As of May 2014, the Directory of Open Access Journals (DOAJ listed close to ten thousand fully open access, peer reviewed, scholarly journals. Most of these journals do not charge article processing charges (APCs. This article reports the results of a survey of the 2567 journals, or 26% of journals listed in DOAJ, that do have APCs based on a sample of 1432 of these journals. Results indicate a volatile sector that would make future APCs difficult to predict for budgeting purposes. DOAJ and publisher title lists often did not closely match. A number of journals were found on examination not to have APCs. A wide range of publication costs was found for every publisher type. The average (mean APC of $964 contrasts with a mode of $0. At least 61% of publishers using APCs are commercial in nature, while many publishers are of unknown types. The vast majority of journals charging APCs (80% were found to offer one or more variations on pricing, such as discounts for authors from mid to low income countries, differential pricing based on article type, institutional or society membership, and/or optional charges for extras such as English language editing services or fast track of articles. The complexity and volatility of this publishing landscape is discussed.

  14. A negative feedback modulator of antigen processing evolved from a frameshift in the cowpox virus genome.

    Directory of Open Access Journals (Sweden)

    Jiacheng Lin

    2014-12-01

    Full Text Available Coevolution of viruses and their hosts represents a dynamic molecular battle between the immune system and viral factors that mediate immune evasion. After the abandonment of smallpox vaccination, cowpox virus infections are an emerging zoonotic health threat, especially for immunocompromised patients. Here we delineate the mechanistic basis of how cowpox viral CPXV012 interferes with MHC class I antigen processing. This type II membrane protein inhibits the coreTAP complex at the step after peptide binding and peptide-induced conformational change, in blocking ATP binding and hydrolysis. Distinct from other immune evasion mechanisms, TAP inhibition is mediated by a short ER-lumenal fragment of CPXV012, which results from a frameshift in the cowpox virus genome. Tethered to the ER membrane, this fragment mimics a high ER-lumenal peptide concentration, thus provoking a trans-inhibition of antigen translocation as supply for MHC I loading. These findings illuminate the evolution of viral immune modulators and the basis of a fine-balanced regulation of antigen processing.

  15. (AC)3: A German Initiative to Study Arctic Amplification—Climate Relevant Atmospheric and Surface Processes and Feedback Mechanisms

    Science.gov (United States)

    Spreen, G.; Wendisch, M.; Brückner, M.

    2016-12-01

    Within the last 25 years a remarkable increase of the Arctic near-surface air temperature exceeding the global warming by a factor of at least two has been observed. This phenomenon is commonly referred to as Arctic Amplification. The warming results in rather dramatic changes of a variety of climate parameters. For example, the Arctic sea ice has declined significantly. This ice retreat has been well identified by satellite measurements. Over recent decades, significant progress has been made in two main scientific areas: (i) the capabilities of in-situ measurements and remote sensing techniques to observe key physico-chemical atmospheric constituents and surface parameters at high latitudes have advanced impressively, and (ii) the computational skills and power used to model individual feedback mechanisms on small scales have improved notably. It is, therefore, timely to exploit synergistically these new developments to enhance our knowledge of the origins of the observed Arctic climate changes. To achieve this aim a new Transregional Collaborative Research Center (TR 172) was launched in January 2016 called "ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms" with the acronym (AC)3. Observations from instrumentation on satellites, aircraft, tethered balloons, research vessels, and a selected set of ground-based sites will be integrated in dedicated campaigns, as well as being combined with long-term measurements. The field studies will be conducted in different seasons and meteorological conditions, covering a suitably wide range of spatial and temporal scales. They will be performed in an international context and in close collaboration with modelling activities. The latter utilize a hierarchy of process, meso-scale, regional, and global models to bridge the spatio-temporal scales from local individual processes to appropriate climate signals. The models will serve to guide the campaigns, to analyse the

  16. Survey of Bayesian Models for Modelling of Stochastic Temporal Processes

    Energy Technology Data Exchange (ETDEWEB)

    Ng, B

    2006-10-12

    This survey gives an overview of popular generative models used in the modeling of stochastic temporal systems. In particular, this survey is organized into two parts. The first part discusses the discrete-time representations of dynamic Bayesian networks and dynamic relational probabilistic models, while the second part discusses the continuous-time representation of continuous-time Bayesian networks.

  17. Understanding Feedback: A Learning Theory Perspective

    Science.gov (United States)

    Thurlings, Marieke; Vermeulen, Marjan; Bastiaens, Theo; Stijnen, Sjef

    2013-01-01

    This article aims to review literature on feedback to teachers. Because research has hardly focused on feedback among teachers, the review's scope also includes feedback in classrooms. The review proposes that the effectiveness of feedback and feedback processes depend on the learning theory adhered to. Findings show that regardless of the…

  18. Variables that affect the process and outcome of feedback, relevant for medical training : A meta-review

    NARCIS (Netherlands)

    van de Ridder, J. M Monica; Mcgaghie, William C.; Stokking, Karel M.; ten Cate, Olle T J

    2015-01-01

    Context: Feedback is considered important in medical education. The literature is not clear about the mechanisms that contribute to its effects, which are often small to moderate and at times contradictory. A variety of variables seem to influence the impact of feedback on learning. The aim of this

  19. Variables that affect the process and outcome of feedback, relevant for medical training : a meta-review

    NARCIS (Netherlands)

    van de Ridder, J.M.M.; McGaghie, W.C.; Stokking, K.M.; ten Cate, TJ

    2015-01-01

    Context Feedback is considered important in medical education. The literature is not clear about the mechanisms that contribute to its effects, which are often small to moderate and at times contradictory. A variety of variables seem to influence the impact of feedback on learning. The aim of this s

  20. Impact of changes in the formulation of cloud-related processes on model biases and climate feedbacks

    NARCIS (Netherlands)

    Lacagnina, C.; Selten, F.; Siebesma, A.P.

    2014-01-01

    To test the impact of modeling uncertainties and biases on the simulation of cloud feedbacks, several configurations of the EC-Earth climate model are built altering physical parameterizations. An overview of the various radiative feedbacks diagnosed from the reference EC-Earth configuration is

  1. Autonomous Closed-Loop Tasking, Acquisition, Processing, and Evaluation for Situational Awareness Feedback

    Science.gov (United States)

    Frye, Stuart; Mandl, Dan; Cappelaere, Pat

    2016-01-01

    This presentation describes the closed loop satellite autonomy methods used to connect users and the assets on Earth Orbiter- 1 (EO-1) and similar satellites. The base layer is a distributed architecture based on Goddard Mission Services Evolution Concept (GMSEC) thus each asset still under independent control. Situational awareness is provided by a middleware layer through common Application Programmer Interface (API) to GMSEC components developed at GSFC. Users setup their own tasking requests, receive views into immediate past acquisitions in their area of interest, and into future feasibilities for acquisition across all assets. Automated notifications via pubsub feeds are returned to users containing published links to image footprints, algorithm results, and full data sets. Theme-based algorithms are available on-demand for processing.

  2. Constraints on feedback processes during the formation of early-type galaxies

    CERN Document Server

    Trevisan, Marina; de la Rosa, Ignacio; La Barbera, Francesco; de Carvalho, Reinaldo

    2012-01-01

    Galaxies are found to obey scaling relations between a number of observables. These relations follow different trends at the low- and the high-mass ends. The processes driving the curvature of scaling relations remain uncertain. In this letter, we focus on the specific family of early-type galaxies, deriving the star formation histories of a complete sample of visually classified galaxies from SDSS-DR7 over the redshift range 0.01

  3. FRET imaging and statistical signal processing reveal positive and negative feedback loops regulating the morphology of randomly migrating HT-1080 cells.

    Science.gov (United States)

    Kunida, Katsuyuki; Matsuda, Michiyuki; Aoki, Kazuhiro

    2012-05-15

    Cell migration plays an important role in many physiological processes. Rho GTPases (Rac1, Cdc42, RhoA) and phosphatidylinositols have been extensively studied in directional cell migration. However, it remains unclear how Rho GTPases and phosphatidylinositols regulate random cell migration in space and time. We have attempted to address this issue using fluorescence resonance energy transfer (FRET) imaging and statistical signal processing. First, we acquired time-lapse images of random migration of HT-1080 fibrosarcoma cells expressing FRET biosensors of Rho GTPases and phosphatidyl inositols. We developed an image-processing algorithm to extract FRET values and velocities at the leading edge of migrating cells. Auto- and cross-correlation analysis suggested the involvement of feedback regulations among Rac1, phosphatidyl inositols and membrane protrusions. To verify the feedback regulations, we employed an acute inhibition of the signaling pathway with pharmaceutical inhibitors. The inhibition of actin polymerization decreased Rac1 activity, indicating the presence of positive feedback from actin polymerization to Rac1. Furthermore, treatment with PI3-kinase inhibitor induced an adaptation of Rac1 activity, i.e. a transient reduction of Rac1 activity followed by recovery to the basal level. In silico modeling that reproduced the adaptation predicted the existence of a negative feedback loop from Rac1 to actin polymerization. Finally, we identified MLCK as the probable controlling factor in the negative feedback. These findings quantitatively demonstrate positive and negative feedback loops that involve actin, Rac1 and MLCK, and account for the ordered patterns of membrane dynamics observed in randomly migrating cells.

  4. AIRS-Observed Interrelationships of Anomaly Time-series of Moist Process-Related Parameters and Inferred Feedback Values on Various Spatial Scales

    Science.gov (United States)

    Molnar, G. I.; Susskind, J.; Iredell, L.

    2011-12-01

    There are some climate feedbacks, especially those associated with moist processes, which are not very well represented in GCMs, the primary tools to predict future climate changes associated with man's ever increasing influences on our planet. Here, we make use of the first 9 years of AIRS observations to evaluate interrelationships/correlations of atmospheric moist parameter anomalies computed from AIRS Version 5 Level-3 products, and demonstrate their usefulness to calculate certain feedback strength values. Note that a rather lively debate has flared up again on the possible usability of shorter-term, satellite-observed climate parameter anomalies for estimating climate sensitivity, i. e., the inferred strength of various (mostly moist processes related) feedbacks. Nevertheless, recent works, in particular analyses by Dessler, have pointed out the usefulness of these shorter term (but reliable) datasets in assessing global water vapor and cloud feedbacks. First we evaluate AIRS-observed interrelationships of anomaly time-series of water vapor, clouds, OLR and temperature on various spatial scales using 1x1 Degree resolution (a common GCM scale) 9-year long (Sept. 2002 through Aug. 2011) monthly anomaly time-series as starting points. We also find significant correlations among the 1x1 Degree average rate of change maps themselves, as well as among the deep tropical anomaly Hovmöller diagrams. We argue that for GCMs to be trusted for predicting longer-term climate variability, e. g., that due to global warming, they should be able to reproduce these observed relationships/metrics as closely as possible. Next, we evaluate the AIRS-observed water vapor feedback on global to regional scales. For cloud feedback, we demonstrate that unlike the global cloud feedback, which may require additional decades of data to compute reliably, regional cloud feedback strengths may already be assessed with sufficient accuracy to provide "benchmarks" for GCMs. The longwave cloud

  5. Does Structured Quizzing with Process Specific Feedback Lead to Learning Gains in an Active Learning Geoscience Classroom?

    Science.gov (United States)

    Palsole, S.; Serpa, L. F.

    2013-12-01

    There is a great realization that efficient teaching in the geosciences has the potential to have far reaching effects in outreach to decision and policy makers (Herbert, 2006; Manduca & Mogk, 2006). This research in turn informs educators that the geosciences by the virtue of their highly integrative nature play an important role in serving as an entry point into STEM disciplines and helping developing a new cadre of geoscientists, scientists and a general population with an understanding of science. Keeping these goals in mind we set to design introductory geoscience courses for non-majors and majors that move away from the traditional lecture models which don't necessarily contribute well to knowledge building and retention ((Handelsman et al., 2007; Hake, 1997) to a blended active learning classroom where basic concepts and didactic information is acquired online via webquests, lecturettes and virtual field trips and the face to face portions of the class are focused on problem solving exercises. The traditional way to ensure that students are prepared for the in-class activity is to have the students take a quiz online to demonstrate basic competency. In the process of redesign, we decided to leverage the technology to build quizzes that are highly structured and map to a process (formation of divergent boundaries for example) or sets of earth processes that we needed the students to know before in-class activities. The quizzes can be taken multiple times and provide process specific feedback, thus serving as a heuristic to the students to ensure they have acquired the necessary competency. The heuristic quizzes were developed and deployed over a year with the student data driving the redesign process to ensure synchronicity. Preliminary data analysis indicates a positive correlation between higher student scores on in-class application exercises and time spent on the process quizzes. An assessment of learning gains also indicate a higher degree of self

  6. Formal concept analysis in knowledge processing: a survey on applications

    NARCIS (Netherlands)

    Poelmans, J.; Ignatov, D.I.; Kuznetsov, S.O.; Dedene, G.

    2013-01-01

    This is the second part of a large survey paper in which we analyze recent literature on Formal Concept Analysis (FCA) and some closely related disciplines using FCA. We collected 1072 papers published between 2003 and 2011 mentioning terms related to Formal Concept Analysis in the title, abstract a

  7. Formal concept analysis in knowledge processing: a survey on applications

    NARCIS (Netherlands)

    Poelmans, J.; Ignatov, D.I.; Kuznetsov, S.O.; Dedene, G.

    2013-01-01

    This is the second part of a large survey paper in which we analyze recent literature on Formal Concept Analysis (FCA) and some closely related disciplines using FCA. We collected 1072 papers published between 2003 and 2011 mentioning terms related to Formal Concept Analysis in the title, abstract

  8. Agree or Disagree? Cognitive Processes in Answering Contrastive Survey Questions

    Science.gov (United States)

    Kamoen, Naomi; Holleman, Bregje; Mak, Pim; Sanders, Ted; Van Den Bergh, Huub

    2011-01-01

    Survey designers have long assumed that respondents who disagree with a negative question ("This policy is bad.": "Yes" or "No"; 2-point scale) will agree with an equivalent positive question ("This policy is good.": "Yes" or "No"; 2-point scale). However, experimental evidence has proven otherwise: Respondents are more likely to disagree with…

  9. Survey of potential chlorine production processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-04-01

    This report is part of the ongoing study of industrial electrochemical processes for the purpose of identifying methods of improving energy efficiencies. A computerized literature search of past and current chlorine generation methods was performed to identify basic chlorine production processes. Over 200 pertinent references are cited involving 20 separate and distinct chlorine processes. Each basic process is evaluated for its engineering and economic viability and energy efficiency. A flow diagram is provided for each basic process. Four criteria are used to determine the most promising processes: raw material availability, type and amount of energy required, by-product demand/disposal and status of development. The most promising processes are determined to be the membrane process (with and without catalytic electrodes), Kel-Chlor, Mobay (direct electrolysis of hydrogen chloride), the Shell process (catalytic oxidation of hydrogen chloride) and oxidation of ammonium chloride. Each of these processes is further studied to determine what activities may be pursued.

  10. Formativ Feedback

    DEFF Research Database (Denmark)

    Hyldahl, Kirsten Kofod

    Denne bog undersøger, hvordan lærere kan anvende feedback til at forbedre undervisningen i klasselokalet. I denne sammenhæng har John Hattie, professor ved Melbourne Universitet, udviklet en model for feedback, hvilken er baseret på synteser af meta-analyser. I 2009 udgav han bogen "Visible...

  11. PROVIDING FEEDBACK ON STUDENT WORK IN DISTANCE EDUCATION IN TURKEY: Practices and Recommendations

    Directory of Open Access Journals (Sweden)

    Sibel HISMANOGLU

    2009-10-01

    Full Text Available In distance education, providing feedback on student work has a key role in facilitating learning and teacher- student dialogue. This article examines the distance learning context and providing feedback in this great but challenging system. It draws on the experiences of 200 distance learners enrolled in different programs in the Open Education Faculty at Anadolu University in Turkey. Its purpose is to find out whether distance students are provided any feedback by their faculty, whether they think that feedback provision is beneficial in distance learning process, and lastly whether they would like their faculty to provide them with some feedback. The survey is based on a questionnaire including three questions to which distance learners can respond briefly as yes or no and, if desired, they can expand their ideas with their own sentences. The results of the study suggest that distance learners are , on the whole, provided no feedback. Of 200 DL, 180 % of them regard feedback provision as a beneficial part of their distance learning process and want to have some feedback mechanisms in their faculty, yet 20% of the learners think just the opposite by saying that it is not something beneficial and they do not need it. In the conclusion part, considering the high proportion in demand of feedback provision, certain feedback mechanisms will be introduced to make the distance learning process more appealing, encouraging, and fruitful for distance learners.

  12. Survey and evaluation of current and potential coal beneficiation processes

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S. P.N.; Peterson, G. R.

    1979-03-01

    Coal beneficiation is a generic term used for processes that prepare run-of-mine coal for specific end uses. It is also referred to as coal preparation or coal cleaning and is a means of reducing the sulfur and the ash contents of coal. Information is presented regarding current and potential coal beneficiation processes. Several of the processes reviewed, though not yet commercial, are at various stages of experimental development. Process descriptions are provided for these processes commensurate with the extent of information and time available to perform the evaluation of these processes. Conceptual process designs, preliminary cost estimates, and economic evaluations are provided for the more advanced (from a process development hierarchy viewpoint) processes based on production levels of 1500 and 15,000 tons/day (maf) of cleaned product coal. Economic evaluations of the coal preparation plants are conducted for several project financing schemes and at 12 and 15% annual after-tax rates of return on equity capital. A 9% annual interest rate is used on the debt fraction of the plant capital. Cleaned product coal prices are determined using the discounted cash flow procedure. The study is intended to provide information on publicly known coal beneficiation processes and to indicate the relative costs of various coal beneficiation processes. Because of severe timeconstraints, several potential coal beneficiation processes are not evaluated in great detail. It is recommended that an additional study be conducted to complement this study and to more fully appreciate the potentially significant role of coal beneficiation in the clean burning of coal.

  13. What is the Process Approvals for Survey Research in the Department of Defense (DoD)

    Science.gov (United States)

    2017-04-26

    JAC legal office for an ethics review. To assist you in making this decision about whether to request a legal review, the following examples are... processes are reported to be confusing. The survey approval process between services is inconsistent and time consuming . Barriers, real or perceived...MDW/SGVU SUBJECT: Professional Presentation Approval 11APR 2017 1. Your paper, entitled What is the Process ? Approvals for Survey Research in the

  14. A Survey on Evaluation Factors for Business Process Management Technology

    NARCIS (Netherlands)

    Mutschler, B.; Reichert, M.U.

    2006-01-01

    Estimating the value of business process management (BPM) technology is a difficult task to accomplish. Computerized business processes have a strong impact on an organization, and BPM projects have a long-term cost amortization. To systematically analyze BPM technology from an economic-driven persp

  15. Feedback options in nonlinear numerical finance

    DEFF Research Database (Denmark)

    Hugger, Jens; Mashayekhi, Sima

    2012-01-01

    Feedback options are options where information about the trading of the underlying asset is fed back into the pricing model. This results in nonlinear pricing models. A survey of the literature about feedback options in finance is presented. The pricing model for the full feedback option...

  16. Improving the quality of written feedback using written feedback.

    Science.gov (United States)

    Bartlett, Maggie; Crossley, James; McKinley, Robert

    2017-01-01

    Educational feedback is amongst the most powerful of all learning interventions. (1) Can we measure the quality of written educational feedback with acceptable metrics? (2) Based on such a measure, does a quality improvement (QI) intervention improve the quality of feedback? We developed a QI instrument to measure the quality of written feedback and applied it to written feedback provided to medical students following workplace assessments. We evaluated the measurement characteristics of the QI score using generalisability theory. In an uncontrolled intervention, QI profiles were fed back to GP tutors and pre and post intervention scores compared. A single assessor scoring 6 feedback summaries can discriminate between practices with a reliability of 0.82.The quality of feedback rose for two years after the introduction of the QI instrument and stabilised in the third year. The estimated annual cost to provide this feedback is £12 per practice. Interpretation and recommendations: It is relatively straightforward and inexpensive to measure the quality of written feedback with good reliability. The QI process appears to improve the quality of written feedback. We recommend routine use of a QI process to improve the quality of educational feedback.

  17. Development of a high-value care culture survey: a modified Delphi process and psychometric evaluation.

    OpenAIRE

    Gupta, R.(Panjab University, Chandigarh, India); Moriates, C; Harrison, JD; Valencia, V; Ong, M; Clarke, R.; Steers, N; Hays, RD; Braddock, CH; De Wachter, R

    2016-01-01

    Organisational culture affects physician behaviours. Patient safety culture surveys have previously been used to drive care improvements, but no comparable survey of high-value care culture currently exists. We aimed to develop a High-Value Care Culture Survey (HVCCS) for use by healthcare leaders and training programmes to target future improvements in value-based care.We conducted a two-phase national modified Delphi process among 28 physicians and nurse experts with diverse backgrounds. We...

  18. Global climate feedbacks

    Energy Technology Data Exchange (ETDEWEB)

    Manowitz, B.

    1990-10-01

    The important physical, chemical, and biological events that affect global climate change occur on a mesoscale -- requiring high spatial resolution for their analysis. The Department of Energy has formulated two major initiatives under the US Global Change Program: ARM (Atmospheric Radiation Measurements), and CHAMMP (Computer Hardware Advanced Mathematics and Model Physics). ARM is designed to use ground and air-craft based observations to document profiles of atmospheric composition, clouds, and radiative fluxes. With research and models of important physical processes, ARM will delineate the relationships between trace gases, aerosol and cloud structure, and radiative transfer in the atmosphere, and will improve the parameterization of global circulation models. The present GCMs do not model important feedbacks, including those from clouds, oceans, and land processes. The purpose of this workshop is to identify such potential feedbacks, to evaluate the uncertainties in the feedback processes (and, if possible, to parameterize the feedback processes so that they can be treated in a GCM), and to recommend research programs that will reduce the uncertainties in important feedback processes. Individual reports are processed separately for the data bases.

  19. Survey of electrochemical metal winning processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Vaaler, L.E.

    1979-03-01

    The subject program was undertaken to find electrometallurgical technology that could be developed into energy saving commercial metal winning processes. Metals whose current production processes consume significant energy (excepting copper and aluminum) are magnesium, zinc, lead, chromium, manganese, sodium, and titanium. The technology of these metals, with the exception of titanium, was reviewed. Growth of titanium demand has been too small to justify the installation of an electrolyte process that has been developed. This fact and the uncertainty of estimates of future demand dissuaded us from reviewing titanium technology. Opportunities for developing energy saving processes were found for magnesium, zinc, lead, and sodium. Costs for R and D and demonstration plants have been estimated. It appeared that electrolytic methods for chromium and manganese cannot compete energywise or economically with the pyrometallurgical methods of producing the ferroalloys, which are satisfactory for most uses of chromium and manganese.

  20. Survey of potential processes for the manufacture of aluminium

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-01

    The following alternative processes to the Hall-Heroult cell for the production of primary aluminum - direct carbothermic reduction of alumina are considered; reduction of bauxite to an aluminum-silicon alloy; the subchloride process; the disproportionation of aluminum sulphide; the production through a nitride intermediate; and electrolysis of aluminum chloride, aluminum sulphide and aluminum nitride; and plating from non aqueous solvents. Comparisons of energy consumption are made with current Hall-Heroult technology and with projected improved technology - particularly titanium diboride cathodes and permanent anodes. The major conclusion is that the only alternative technology at present is the Alcoa chloride electrolysis process but that sulphide and nitride electrolytic processes offer potential advantages in the future. With the exception of thermal reduction to an aluminum - silicon alloy none of the carbothermic processes is competitive because they require electric furnaces. Significant improvements in energy consumption could be achieved with titanium diboride cathodes in the Hall-Heroult cell though a long lived cathode has yet to be demonstrated.

  1. Survey of real-time processing systems for big data

    DEFF Research Database (Denmark)

    Liu, Xiufeng; Lftikhar, Nadeem; Xie, Xike

    2014-01-01

    In recent years, real-time processing and analytics systems for big data–in the context of Business Intelligence (BI)–have received a growing attention. The traditional BI platforms that perform regular updates on daily, weekly or monthly basis are no longer adequate to satisfy the fast......-changing business environments. However, due to the nature of big data, it has become a challenge to achieve the real-time capability using the traditional technologies. The recent distributed computing technology, MapReduce, provides off-the-shelf high scalability that can significantly shorten the processing time...... for big data; Its open-source implementation such as Hadoop has become the de-facto standard for processing big data, however, Hadoop has the limitation of supporting real-time updates. The improvements in Hadoop for the real-time capability, and the other alternative real-time frameworks have been...

  2. Survey of real-time processing systems for big data

    DEFF Research Database (Denmark)

    Iftikhar, Nadeem

    2014-01-01

    In recent years, real-time processing and analytics systems for big data–in the context of Business Intelligence (BI)–have received a growing attention. The traditional BI platforms that perform regular updates on daily, weekly or monthly basis are no longer adequate to satisfy the fast......-changing business environments. However, due to the nature of big data, it has become a challenge to achieve the real-time capability using the traditional technologies. The recent distributed computing technology, MapReduce, provides off-the-shelf high scalability that can significantly shorten the processing time...... for big data; Its open-source implementation such as Hadoop has become the de-facto standard for processing big data, however, Hadoop has the limitation of supporting real-time updates. The improvements in Hadoop for the real-time capability, and the other alternative real-time frameworks have been...

  3. Feedback in analog circuits

    CERN Document Server

    Ochoa, Agustin

    2016-01-01

    This book describes a consistent and direct methodology to the analysis and design of analog circuits with particular application to circuits containing feedback. The analysis and design of circuits containing feedback is generally presented by either following a series of examples where each circuit is simplified through the use of insight or experience (someone else’s), or a complete nodal-matrix analysis generating lots of algebra. Neither of these approaches leads to gaining insight into the design process easily. The author develops a systematic approach to circuit analysis, the Driving Point Impedance and Signal Flow Graphs (DPI/SFG) method that does not require a-priori insight to the circuit being considered and results in factored analysis supporting the design function. This approach enables designers to account fully for loading and the bi-directional nature of elements both in the feedback path and in the amplifier itself, properties many times assumed negligible and ignored. Feedback circuits a...

  4. Survey of real-time processing systems for big data

    DEFF Research Database (Denmark)

    Liu, Xiufeng; Lftikhar, Nadeem; Xie, Xike

    2014-01-01

    for big data; Its open-source implementation such as Hadoop has become the de-facto standard for processing big data, however, Hadoop has the limitation of supporting real-time updates. The improvements in Hadoop for the real-time capability, and the other alternative real-time frameworks have been...

  5. Effects of performance feedback and coaching on the problem-solving process: Improving the integrity of implementation and enhancing student outcomes

    Science.gov (United States)

    Lundahl, Allison A.

    Schools implementing Response to Intervention (RtI) procedures frequently engage in team problem-solving processes to address the needs of students who require intensive and individualized services. Because the effectiveness of the problem-solving process will impact the overall success of RtI systems, the present study was designed to learn more about how to strengthen the integrity of the problem-solving process. Research suggests that school districts must ensure high quality training and ongoing support to enhance the effectiveness, acceptability, and sustainability of the problem-solving process within an RtI model; however, there is a dearth of research examining the effectiveness of methods to provide this training and support. Consequently, this study investigated the effects of performance feedback and coaching strategies on the integrity with which teams of educators conducted the problem-solving process in schools. In addition, the relationships between problem-solving integrity, teacher acceptability, and student outcomes were examined. Results suggested that the performance feedback increased problem-solving procedural integrity across two of the three participating schools. Conclusions about the effectiveness of the (a) coaching intervention and (b) interventions implemented in the third school were inconclusive. Regression analyses indicated that the integrity with which the teams conducted the problem-solving process was a significant predictor of student outcomes. However, the relationship between problem-solving procedural integrity and teacher acceptability was not statistically significant.

  6. Feedback and Incentives

    DEFF Research Database (Denmark)

    Eriksson, Tor Viking; Poulsen, Anders; Villeval, Marie Claire

    2009-01-01

    This paper experimentally investigates the impact of different pay schemes and relative performance feedback policies on employee effort. We explore three feedback rules: no feedback on relative performance, feedback given halfway through the production period, and continuously updated feedback. ...

  7. Survey of control performance in quantum information processing

    Science.gov (United States)

    Hocker, David; Zheng, Yicong; Kosut, Robert; Brun, Todd; Rabitz, Herschel

    2016-11-01

    There is a rich variety of physics underlying the fundamental gating operations for quantum information processing (QIP). A key aspect of a QIP system is how noise may enter during quantum operations and how suppressing or correcting its effects can best be addressed. Quantum control techniques have been developed to specifically address this effort, although a detailed classification of the compatibility of controls schemes with noise sources found in common quantum systems has not yet been performed. This work numerically examines the performance of modern control methods for suppressing decoherence in the presence of noise forms found in viable quantum systems. The noise-averaged process matrix for controlled one-qubit and two-qubit operations are calculated across noise found in systems driven by Markovian open quantum dynamics. Rather than aiming to describe the absolute best control scheme for a given physical circumstance, this work serves instead to classify quantum control behavior across a large class of noise forms so that opportunities for improving QIP performance may be identified.

  8. Survey of control performance in quantum information processing

    Science.gov (United States)

    Hocker, David; Zheng, Yicong; Kosut, Robert; Brun, Todd; Rabitz, Herschel

    2016-08-01

    There is a rich variety of physics underlying the fundamental gating operations for quantum information processing (QIP). A key aspect of a QIP system is how noise may enter during quantum operations and how suppressing or correcting its effects can best be addressed. Quantum control techniques have been developed to specifically address this effort, although a detailed classification of the compatibility of controls schemes with noise sources found in common quantum systems has not yet been performed. This work numerically examines the performance of modern control methods for suppressing decoherence in the presence of noise forms found in viable quantum systems. The noise-averaged process matrix for controlled one-qubit and two-qubit operations are calculated across noise found in systems driven by Markovian open quantum dynamics. Rather than aiming to describe the absolute best control scheme for a given physical circumstance, this work serves instead to classify quantum control behavior across a large class of noise forms so that opportunities for improving QIP performance may be identified.

  9. Seismoelectric data processing for surface surveys of shallow targets

    Science.gov (United States)

    Haines, S.S.; Guitton, A.; Biondi, B.

    2007-01-01

    The utility of the seismoelectric method relies on the development of methods to extract the signal of interest from background and source-generated coherent noise that may be several orders-of-magnitude stronger. We compare data processing approaches to develop a sequence of preprocessing and signal/noise separation and to quantify the noise level from which we can extract signal events. Our preferred sequence begins with the removal of power line harmonic noise and the use of frequency filters to minimize random and source-generated noise. Mapping to the linear Radon domain with an inverse process incorporating a sparseness constraint provides good separation of signal from noise, though it is ineffective on noise that shows the same dip as the signal. Similarly, the seismoelectric signal and noise do not separate cleanly in the Fourier domain, so f-k filtering can not remove all of the source-generated noise and it also disrupts signal amplitude patterns. We find that prediction-error filters provide the most effective method to separate signal and noise, while also preserving amplitude information, assuming that adequate pattern models can be determined for the signal and noise. These Radon-domain and prediction-error-filter methods successfully separate signal from data. ?? 2007 Society of Exploration Geophysicists.

  10. Privacy preserving processing of genomic data: A survey.

    Science.gov (United States)

    Akgün, Mete; Bayrak, A Osman; Ozer, Bugra; Sağıroğlu, M Şamil

    2015-08-01

    Recently, the rapid advance in genome sequencing technology has led to production of huge amount of sensitive genomic data. However, a serious privacy challenge is confronted with increasing number of genetic tests as genomic data is the ultimate source of identity for humans. Lately, privacy threats and possible solutions regarding the undesired access to genomic data are discussed, however it is challenging to apply proposed solutions to real life problems due to the complex nature of security definitions. In this review, we have categorized pre-existing problems and corresponding solutions in more understandable and convenient way. Additionally, we have also included open privacy problems coming with each genomic data processing procedure. We believe our classification of genome associated privacy problems will pave the way for linking of real-life problems with previously proposed methods. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Testing AGN feedback models in galaxy evolution

    Science.gov (United States)

    Shin, Min-Su

    Galaxy formation and evolution have been one of the most challenging problems in astrophysics. A single galaxy has various components (stars, atomic and molecular gas, a supermassive black hole, and dark matter) and has interacted with its cosmic environment throughout its history. A key issue in understanding galaxy evolution is to find the dominant physical processes in the interactions between the components of a galaxy and between a galaxy and its environment. AGN feedback has been proposed as a key process to suppress late star formation in massive elliptical galaxies and as a general consequence of galaxy mergers and interactions. In this thesis, I investigate feedback effects from active galactic nuclei (AGN) using a new simulation code and data from the Sloan Digital Sky Survey. In the first chapter, I test purely mechanical AGN feedback models via a nuclear wind around the central SMBH in elliptical galaxies by comparing simulation results to four well-defined observational constraints: the mass ratio between the SMBH and its host galaxy, the lifetime of the quasar phase, the X-ray luminosity from the hot interstellar medium, and the mass fraction of young stars. Even though purely mechanical AGN feedback is commonly assumed in cosmological simulations, I find that it is inadequate, and cannot reproduce all four observational constraints simultaneously. This result suggests that both mechanical and radiative feedback modes are important physical processes. In the second chapter, I simulate the coevolution of the SMBH and its host galaxy under different environments, represented by different amounts of gas stripping. Though the connection between environment and galaxy evolution has been well-studied, environmental effects on the growth of the SMBH have not been answered yet. I find that strong gas stripping, which satellite galaxies might experience, highly suppresses SMBH mass accretion and AGN activity. Moreover, the suppression of the SMBH growth is

  12. Survey of biological processes for odor reduction; Kartlaeggning och studie av biologiska processer foer luktreduktion

    Energy Technology Data Exchange (ETDEWEB)

    Arrhenius, Karine; Rosell, Lars [SP Technical Research Inst. of Sweden, Boraas (Sweden); Hall, Gunnar [SIK Swedish Inst. for Food and Biotechnology, Gothenburg (Sweden)

    2009-09-15

    This project aims to characterize chemical and subsequently odor emissions from a digester plant located closed to Boraas in Sweden (Boraas Energi och Miljoe AB). The digestion produces mainly 2 by-products, biogas and high quality organic biofertilizer. Biogas is a renewable source of electrical and heat energy and subsequently digester have a promising future. Unfortunately, release of unpleasant odours is one of the problems that may limit development of the technique as odours strongly influence the level of acceptance of the neighbours. The number of complaints due to odours depends mostly, upon the degree of odour release, the weather condition and plant environment (which influence the risks for spreading out), and the tolerance of the neighbours. These parameters are strongly variable. Many processes inside the plant distributed on a large surface may contribute to odour release. Chemical emissions were studied, in this project, by extensive sampling inside the plant. Results were then evaluated regarding risk for odour releases. The goal was to suggest controls and routines to limit releases. The conditions leading to the higher risks for odour emissions were studied by performing sampling at different periods of the year and subsequently different weather conditions. At first, places for measurement were chosen together with personal of the plant. Three zones are considered to mainly contribute to the odour emissions: the landfill region, the cisterns region and the leaching lake region. Totally 13 places were studied with regard to odour and chemical emissions under 2008-2009 at different weather conditions. Some results from a previous project (2007) are also presented here. Results show that the spreading out of can be maintained to an acceptable level as long as the plant is functioning without disturbances. The early stages of the treatment of waste should be confined in locals with closed doors to avoid spreading out of odours. Through controlled

  13. A survey of geothermal process heat applications in Guatemala: An engineering survey

    Energy Technology Data Exchange (ETDEWEB)

    Altseimer, J.H.; Edeskuty, F.J.

    1988-08-01

    This study investigates how process heat from Guatemala's geothermal energy resources can be developed to reduce Guatemala's costly importation of oil, create new employment by encouraging new industry, and reduce fuel costs for existing industry. This investigation was funded by the US Agency for International Development and carried out jointly by the Guatemalan Government and the Los Alamos National Laboratory. Two sites, Amatitlan and Zunil, are being developed geothermally. Amatitlan is in the better industrial area but Zunil's geothermal development is more advanced. The industry around Zunil is almost exclusively agricultural and the development of an agricultural processing plant (freezing, dehydration, and cold storage) using geothermal heat is recommended. Similar developments throughout the volcanic zones of Guatemala are possible. Later, when the field at Amatitlan has been further developed, an industrial park can be planned. Potential Amatitlan applications are the final stage of salt refining, a thermal power plant, hospital/hotel heating and cooling, steam curing of concrete blocks, production of alcohol from sugar cane, and production of polyethylene from ethanol. Other special developments such as water pumping for the city of Guatemala and the use of moderate-temperature geothermal fluids for localized power production are also possible. 12 refs., 13 figs., 14 tabs.

  14. Assessment for 1983-4 School Year. Administrative/Supervisory Performance Review Process. Survey Results.

    Science.gov (United States)

    Gallagher, Michael P.

    School administrators and supervisors who were evaluated using the Cleveland, Ohio City School District's Administrator/Supervisory Review Process were surveyed concerning their opinions of the review process. The questionnaire, which was returned by 203 principals, assistant principals, and other supervisory staff out of a total of 376…

  15. Social Workers' Orientation toward the Evidence-Based Practice Process: A Dutch Survey

    Science.gov (United States)

    van der Zwet, Renske J. M.; Kolmer, Deirdre M. Beneken genaamd; Schalk, René

    2016-01-01

    Objectives: This study assesses social workers' orientation toward the evidence-based practice (EBP) process and explores which specific variables (e.g. age) are associated. Methods: Data were collected from 341 Dutch social workers through an online survey which included a Dutch translation of the EBP Process Assessment Scale (EBPPAS), along with…

  16. Using Screencasts to Enhance Assessment Feedback: Students' Perceptions and Preferences

    Science.gov (United States)

    Marriott, Pru; Teoh, Lim Keong

    2012-01-01

    In the UK, assessment and feedback have been regularly highlighted by the National Student Survey as critical aspects that require improvement. An innovative approach to delivering feedback that has proved successful in non-business-related disciplines is the delivery of audio and visual feedback using screencast technology. The feedback on…

  17. Observational Signatures Of Agn Feedback Across Cosmic Time

    Science.gov (United States)

    Wylezalek, Dominika

    2017-06-01

    While many compelling models of AGN feedback exist, there is no clear data-driven picture of how winds are launched, how they propagate through the galaxy and what impact they have on the galactic gas. Recent work suggests that AGN luminosity plays an important role. The following described projects focus on understanding the power, reach and impact of feedback processes exerted by AGN of different power. I first describe recent efforts in our group of relating feedback signatures in powerful quasars to the specific star formation rate in their host galaxies, where our results are consistent with the AGN having a `negative' impact through feedback on the galaxies' star formation history. Feedback signatures seem to be best observable in gas-rich galaxies where the coupling of the AGN-driven wind to the gas is strongest, in agreement with recent simulations. But how and where does this quenching happen? Is it accomplished through the mechanical action of jets or through nuclear winds driven by radiation pressure? Finally, I show that AGN signatures and AGN-driven winds can be easily hidden and not be apparent in the integrated spectrum of a galaxy hosting a low/intermediate-luminosity AGN. Using data from the new SDSS-IV MaNGA survey, we have developed a new AGN selection algorithm tailored to IFU data and we are uncovering a much more nuanced picture of AGN activity allowing us to discover AGN signatures at large distances from the galaxy center. This implies that large IFU surveys, such as the SDSS-IV MaNGA survey, might uncover many previously unknown AGN and feedback signatures related to them. Outflows and feedback from low- and intermediate-luminosity AGN might have been underestimated in the past but can potentially significantly contribute to the AGN/host-galaxy self-regulation.

  18. Individual differences in the encoding processes of egocentric and allocentric survey knowledge.

    Science.gov (United States)

    Wen, Wen; Ishikawa, Toru; Sato, Takao

    2013-01-01

    This study examined how different components of working memory are involved in the acquisition of egocentric and allocentric survey knowledge by people with a good and poor sense of direction (SOD). We employed a dual-task method and asked participants to learn routes from videos with verbal, visual, and spatial interference tasks and without any interference. Results showed that people with a good SOD encoded and integrated knowledge about landmarks and routes into egocentric survey knowledge in verbal and spatial working memory, which is then transformed into allocentric survey knowledge with the support of all three components, distances being processed in verbal and spatial working memory and directions in visual and spatial working memory. In contrast, people with a poor SOD relied on verbal working memory and lacked spatial processing, thus failing to acquire accurate survey knowledge. Based on the results, a possible model for explaining individual differences in spatial knowledge acquisition is proposed. Copyright © 2012 Cognitive Science Society, Inc.

  19. Interpreting Feedback: A Discourse Analysis of Teacher Feedback and Student Identity

    Science.gov (United States)

    Torres, J. T.; Anguiano, Carlos J.

    2016-01-01

    Feedback has typically been studied as a means of improving academic performance. Few studies inquire into the processes by which feedback shapes student identity. The authors carry out a discourse analysis of written comments to explore how feedback is discursively constructed by both teachers and students. Analysis of written feedback,…

  20. A Survey of Researches on Evaluation and Feedback of EFL Writing in China (2000 -2013)%国内二语写作评估反馈研究调查(2000-2013)

    Institute of Scientific and Technical Information of China (English)

    朱岩岩

    2014-01-01

    2000-2013年,二语写作评估反馈研究论文的总数量逐年递增,以定量、定性研究为主的实证性研究在缓慢上升,以经验式、总结式为主的非实证性研究的论文仍占多数;二语写作评估反馈研究开始借鉴多媒体技术、语料库等现代教学手段;研究内容上涵盖二语写作中的自我评估、教师反馈、同伴互评、计算机辅助评估、多级评估模式等诸多方面。%From 2000 to 2013 ,the total amount of academic publications on evaluation and feed-back of EFL is increasing ,but it occupies a small percentage in the core journals of foreign lan-guage studies .In terms of research methods ,non_material research articles are decreasing ,while empirical studies grow steadily .Meanwhile researches on evaluation and feedback of EFL start to take advantages of the development of modern teaching technologies ,such as multimedia net teaching platform and data driven language learning .The researches cover a wide range of topics , including self assessment ,teacher’s feedback ,peer feedback ,computer_assisted evaluation ,and multi_level evaluation system ,etc .Based on a comprehensive survey ,this article presents a future direction of evaluation and feedback research of EFL writing in China .

  1. Digital Detection and feedback Fluxgate Magnetometer

    DEFF Research Database (Denmark)

    Piil-Henriksen, J.; Merayo, José M.G.; Nielsen, Otto V;

    1996-01-01

    A new full Earth's field dynamic feedback fluxgate magnetometer is described. It is based entirely on digital signal processing and digital feedback control, thereby replacing the classical second harmonic tuned analogue electronics by processor algorithms. Discrete mathematical cross...

  2. Clustering of Mg II absorption line systems around massive galaxies: an important constraint on feedback processes in galaxy formation

    Science.gov (United States)

    Kauffmann, Guinevere; Nelson, Dylan; Ménard, Brice; Zhu, Guangtun

    2017-07-01

    We use the latest version of the metal line absorption catalogue of Zhu & Ménard to study the clustering of Mg II absorbers around massive galaxies (˜1011.5 M⊙), quasars and radio-loud active galactic nuclei (AGNs) with redshifts between 0.4 and 0.75. Clustering is evaluated in two dimensions by binning absorbers both in the projected radius and velocity separation. Excess Mg II is detected around massive galaxies out to Rp = 20 Mpc. At projected radii less than 800 kpc, the excess extends out to velocity separations of 10 000 km s-1. The extent of the high-velocity tail within this radius is independent of the mean stellar age of the galaxy and whether or not it harbours an AGN. We interpret our results using the publicly available Illustris and Millennium simulations. Models where the Mg II absorbers trace the dark matter particle or subhalo distributions do not fit the data. They overpredict the clustering on small scales and do not reproduce the excess high velocity separation Mg II absorbers seen within the virial radius of the halo. The Illustris simulations that include thermal, but not mechanical feedback from AGNs, also do not provide an adequate fit to the properties of the cool halo gas within the virial radius. We propose that the large velocity separation Mg II absorbers trace gas that has been pushed out of the dark matter haloes, possibly by multiple episodes of AGN-driven mechanical feedback acting over long time-scales.

  3. Feedback on household electricity consumption

    DEFF Research Database (Denmark)

    Grønhøj, Alice; Thøgersen, John

    2011-01-01

    consumption, we evaluate the effects of giving households detailed feedback about their electricity consumption on a small liquid crystal display (LCD) screen. Twenty Danish households participated in the study over a 5-month period. A new feedback system was developed in a user-involved innovation process...

  4. The Pairing of Accreting Massive Black Holes in Multiphase Circumnuclear Disks: the Interplay between Radiative Cooling, Star Formation, and Feedback Processes

    CERN Document Server

    Lima, Rafael Souza; Capelo, Pedro R; Bellovary, Jillian M

    2016-01-01

    We study the orbital decay of a pair of massive black holes (BHs), in the mass range 5 * 10^5 - 10^7 Msun, using a large set of hydrodynamical simulations of circumnuclear disks (CNDs) with varying prescriptions for the sub-grid physics of the interstellar medium, from star formation and supernova feedback to BH accretion and its feedback. In the absence of any of such processes, the orbit of the secondary BH in an adiabatic flow decays over timescales of a few Myr to the center of the CND, where the primary BH resides. As soon as strong dissipation operates in CNDs, fragmentation into massive objects the size of giant molecular clouds occurs, causing stochastic torques as well as direct hits that eject the secondary BH out of the disk plane. Once outside the plane, the low-density medium provides only weak drag, and the return to the CND plane is governed by inefficient dynamical friction in a stellar bulge. Ejections are seen to occur in nearly all of runs with cooling, irrespective of which other processes...

  5. In-process monitoring and feedback control for stable production of full-penetration weld in continuous wave fibre laser welding

    Science.gov (United States)

    Kawahito, Yousuke; Ohnishi, Terumasa; Katayama, Seiji

    2009-04-01

    Laser micro-welding has been applied for device sealing in electronics and automobile industries. Welding of corners in goods and products is a problem owing to easier formation of a weld with burn-through, shallow penetration or a non-bonded part when a drastic change in the welding speed or laser power occurs. This research was therefore undertaken with the objective of obtaining a fundamental knowledge of in-process monitoring and feedback control for the stable production of a full-penetration weld with a constant bead width on the bottom surface irrespective of the changes in the laser power and the welding speed. Variation in weld penetration geometry was investigated by rapid deceleration and acceleration in the welding speed during lap welding of pure titanium thin sheets with a continuous wave (CW) single-mode fibre laser beam. The rapid deceleration in the welding speed led to a considerable change in the full-penetration weld geometry or a partially penetrated weld (if the power was accordingly reduced), resulting in the difficulty in the stable production of a full-penetration weld bead. The heat radiation intensity measured from the laser-irradiated area was useful as an in-process monitoring signal for detecting the molten pool size on the laser-irradiated surface. However, the utilization of monitoring of heat radiation was difficult for predicting the weld bead width on the bottom surface due to the formation of partial penetration or the change in the penetration shape. The laser power was controlled at a 4 ms interval according to the heat radiation signal in order to adjust the weld bead width on the laser-irradiated surface to the target weld penetration geometry affected by thermal storage. Consequently, the feedback-controlled laser power produced a stable full-penetration weld with the designed bead width on the bottom surface irrespective of the rapid deceleration of the welding speed and the corresponding decrease in laser power

  6. In-process monitoring and feedback control for stable production of full-penetration weld in continuous wave fibre laser welding

    Energy Technology Data Exchange (ETDEWEB)

    Kawahito, Yousuke; Ohnishi, Terumasa; Katayama, Seiji, E-mail: kawahito@jwri.osaka-u.ac.j [Joining and Welding Research Institute (JWRI), Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

    2009-04-21

    Laser micro-welding has been applied for device sealing in electronics and automobile industries. Welding of corners in goods and products is a problem owing to easier formation of a weld with burn-through, shallow penetration or a non-bonded part when a drastic change in the welding speed or laser power occurs. This research was therefore undertaken with the objective of obtaining a fundamental knowledge of in-process monitoring and feedback control for the stable production of a full-penetration weld with a constant bead width on the bottom surface irrespective of the changes in the laser power and the welding speed. Variation in weld penetration geometry was investigated by rapid deceleration and acceleration in the welding speed during lap welding of pure titanium thin sheets with a continuous wave (CW) single-mode fibre laser beam. The rapid deceleration in the welding speed led to a considerable change in the full-penetration weld geometry or a partially penetrated weld (if the power was accordingly reduced), resulting in the difficulty in the stable production of a full-penetration weld bead. The heat radiation intensity measured from the laser-irradiated area was useful as an in-process monitoring signal for detecting the molten pool size on the laser-irradiated surface. However, the utilization of monitoring of heat radiation was difficult for predicting the weld bead width on the bottom surface due to the formation of partial penetration or the change in the penetration shape. The laser power was controlled at a 4 ms interval according to the heat radiation signal in order to adjust the weld bead width on the laser-irradiated surface to the target weld penetration geometry affected by thermal storage. Consequently, the feedback-controlled laser power produced a stable full-penetration weld with the designed bead width on the bottom surface irrespective of the rapid deceleration of the welding speed and the corresponding decrease in laser power

  7. Gathering Feedback for Teaching: Combining High-Quality Observations with Student Surveys and Achievement Gains. Policy and Practice Brief. MET Project

    Science.gov (United States)

    Kane, Thomas J.; Staiger, Douglas O.

    2012-01-01

    Research has long been clear that teachers matter more to student learning than any other in-school factor. Improving the quality of teaching is critical to student success. Yet only recently have many states and districts begun to take seriously the importance of evaluating teacher performance and providing teachers with the feedback they need to…

  8. Gathering Feedback for Teaching: Combining High-Quality Observations with Student Surveys and Achievement Gains. Policy and Practice Summary. MET Project

    Science.gov (United States)

    Bill & Melinda Gates Foundation, 2012

    2012-01-01

    Research has long been clear that teachers matter more to student learning than any other in-school factor. Improving the quality of teaching is critical to student success. Yet only recently have many states and districts begun to take seriously the importance of evaluating teacher performance and providing teachers with the feedback they need to…

  9. MODEL OF FORMATION OF THE FEEDBACK CHANNEL WITHIN ERGATIC SYSTEMS FOR MONITORING OF QUALITY OF PROCESSES OF FORMATION OF PERSONNEL COMPETENCES

    Directory of Open Access Journals (Sweden)

    Irina Veshneva

    2015-10-01

    Full Text Available The authors of this work develop a management model of quality of process of competences development and support of decision of low-formalized tasks of management of learning quality process. On the basis of research of features of creation of a complex of feedback realization within the "operator - environment - machine" system the model is developed which provides the stage-by-stage evolutionary development of this complex when modeling various external and internal influences, and can be integrated into modern management systems. Systems of images recognition, a status functions method, testing systems, video recording, and photogrammetric methods are used. Taking into account some assumptions, the proposed approach can be widely applied in difficult training complexes, anthropomorphous training systems, in distant education, and for complex assessment of difficult social and economic objects condition.

  10. Active Galactic Nuclei Feedback and Galactic Outflows

    Science.gov (United States)

    Sun, Ai-Lei

    Feedback from active galactic nuclei (AGN) is thought to regulate the growth of supermassive black holes (SMBHs) and galaxies. The most direct evidence of AGN feedback is probably galactic outflows. This thesis addresses the link between SMBHs and their host galaxies from four different observational perspectives. First, I study the local correlation between black hole mass and the galactic halo potential (the MBH - Vc relation) based on Very Large Array (VLA) HI observations of galaxy rotation curves. Although there is a correlation, it is no tighter than the well-studied MBH - sigma* relation between the black hole mass and the potential of the galactic bulge, indicating that physical processes, such as feedback, could link the evolution of the black hole to the baryons in the bulge. In what follows, I thus search for galactic outflows as direct evidence of AGN feedback. Second, I use the Atacama Large Millimeter Array (ALMA) to observe a luminous obscured AGN that hosts an ionized galactic outflow and find a compact but massive molecular outflow that can potentially quench the star formation in 10. 6 years.The third study extends the sample of known ionized outflows with new Magellan long-slit observations of 12 luminous obscured AGN. I find that most luminous obscured AGN (Lbol > 1046 ergs s-1) host ionized outflows on 10 kpc scales, and the size of the outflow correlates strongly with the luminosity of the AGN. Lastly, to capitalize on the power of modern photometric surveys, I experiment with a new broadband imaging technique to study the morphology of AGN emission line regions and outflows. With images from the Sloan Digital Sky Survey (SDSS), this method successfully constructs images of the [OIII]lambda5007 emission line and reveals hundreds of extended emission-line systems. When applied to current and future surveys, such as the Large Synoptic Survey Telescope (LSST), this technique could open a new parameter space for the study of AGN outflows. In

  11. Sensitivity of Seismic Interferometry and Conventional Reflection Seismics at a Landfil to Processing and Survey Errors

    NARCIS (Netherlands)

    Konstantaki, L.A.; Draganov, D.S.; Heimovaara, T.J.; Ghose, R.

    2013-01-01

    Understanding how sensitive the seismic method is to errors that can occur during a seismic survey or during the processing of the seismic data is of high importance for any exploration geophysical project. Our aim is to image the subsurface of a landfill, which is typically a heterogeneous system

  12. A survey of the economics of materials processing in space. [accenting biomedical materials

    Science.gov (United States)

    Miller, B. P.

    1975-01-01

    A survey of the economics of space materials processing has been performed with the objectives of identifying those areas of space materials processing that give preliminary indication of significant economic potential, and to identify possible approaches to quantify the economic potential. It is concluded that limited economic studies have been performed to date, primarily in the area of the processing of inorganic materials, but that the economics of space processing of biological material has not received adequate attention. Specific studies are recommended to evaluate the economic impact of human lymphocyte subgroup separation on organ transplantation, and on the separation and concentration of urokinase producing cells.

  13. Perceiving haptic feedback in virtual reality simulators.

    Science.gov (United States)

    Våpenstad, Cecilie; Hofstad, Erlend Fagertun; Langø, Thomas; Mårvik, Ronald; Chmarra, Magdalena Karolina

    2013-07-01

    To improve patient safety, training of psychomotor laparoscopic skills is often done on virtual reality (VR) simulators outside the operating room. Haptic sensations have been found to influence psychomotor performance in laparoscopy. The emulation of haptic feedback is thus an important aspect of VR simulation. Some VR simulators try to simulate these sensations with handles equipped with haptic feedback. We conducted a survey on how laparoscopic surgeons perceive handles with and without haptic feedback. Surgeons with different levels of experience in laparoscopy were asked to test two handles: Xitact IHP with haptic feedback and Xitact ITP without haptic feedback (Mentice AB, Gothenburg, Sweden), connected to the LapSim (Surgical Science AB, Sweden) VR simulator. They performed two tasks on the simulator before answering 12 questions regarding the two handles. The surgeons were not informed about the differences in the handles. A total of 85 % of the 20 surgeons who participated in the survey claimed that it is important that handles with haptic feedback feel realistic. Ninety percent of the surgeons preferred the handles without haptic feedback. The friction in the handles with haptic feedback was perceived to be as in reality (5 %) or too high (95 %). Regarding the handles without haptic feedback, the friction was perceived as in reality (45 %), too low (50 %), or too high (5 %). A total of 85 % of the surgeons thought that the handle with haptic feedback attempts to simulate the resistance offered by tissue to deformation. Ten percent thought that the handle succeeds in doing so. The surveyed surgeons believe that haptic feedback is an important feature on VR simulators; however, they preferred the handles without haptic feedback because they perceived the handles with haptic feedback to add additional friction, making them unrealistic and not mechanically transparent.

  14. SURVEY

    DEFF Research Database (Denmark)

    SURVEY er en udbredt metode og benyttes inden for bl.a. samfundsvidenskab, humaniora, psykologi og sundhedsforskning. Også uden for forskningsverdenen er der mange organisationer som f.eks. konsulentfirmaer og offentlige institutioner samt marketingsafdelinger i private virksomheder, der arbejder...... med surveys. Denne bog gennemgår alle surveyarbejdets faser og giver en praktisk indføring i: • design af undersøgelsen og udvælgelse af stikprøver, • formulering af spørgeskemaer samt indsamling og kodning af data, • metoder til at analysere resultaterne...

  15. Feedbacks and responses of coral calcification on the Bermuda reef system to seasonal changes in biological processes and ocean acidification

    Science.gov (United States)

    Bates, N. R.; Amat, A.; Andersson, A. J.

    2010-08-01

    Despite the potential impact of ocean acidification on ecosystems such as coral reefs, surprisingly, there is very limited field data on the relationships between calcification and seawater carbonate chemistry. In this study, contemporaneous in situ datasets of seawater carbonate chemistry and calcification rates from the high-latitude coral reef of Bermuda over annual timescales provide a framework for investigating the present and future potential impact of rising carbon dioxide (CO2) levels and ocean acidification on coral reef ecosystems in their natural environment. A strong correlation was found between the in situ rates of calcification for the major framework building coral species Diploria labyrinthiformis and the seasonal variability of [CO32-] and aragonite saturation state Ωaragonite, rather than other environmental factors such as light and temperature. These field observations provide sufficient data to hypothesize that there is a seasonal "Carbonate Chemistry Coral Reef Ecosystem Feedback" (CREF hypothesis) between the primary components of the reef ecosystem (i.e., scleractinian hard corals and macroalgae) and seawater carbonate chemistry. In early summer, strong net autotrophy from benthic components of the reef system enhance [CO32-] and Ωaragonite conditions, and rates of coral calcification due to the photosynthetic uptake of CO2. In late summer, rates of coral calcification are suppressed by release of CO2 from reef metabolism during a period of strong net heterotrophy. It is likely that this seasonal CREF mechanism is present in other tropical reefs although attenuated compared to high-latitude reefs such as Bermuda. Due to lower annual mean surface seawater [CO32-] and Ωaragonite in Bermuda compared to tropical regions, we anticipate that Bermuda corals will experience seasonal periods of zero net calcification within the next decade at [CO32-] and Ωaragonite thresholds of ~184 μmoles kg-1 and 2.65. However, net autotrophy of the reef

  16. Feedbacks and responses of coral calcification on the Bermuda reef system to seasonal changes in biological processes and ocean acidification

    Directory of Open Access Journals (Sweden)

    N. R. Bates

    2010-08-01

    Full Text Available Despite the potential impact of ocean acidification on ecosystems such as coral reefs, surprisingly, there is very limited field data on the relationships between calcification and seawater carbonate chemistry. In this study, contemporaneous in situ datasets of seawater carbonate chemistry and calcification rates from the high-latitude coral reef of Bermuda over annual timescales provide a framework for investigating the present and future potential impact of rising carbon dioxide (CO2 levels and ocean acidification on coral reef ecosystems in their natural environment. A strong correlation was found between the in situ rates of calcification for the major framework building coral species Diploria labyrinthiformis and the seasonal variability of [CO32-] and aragonite saturation state Ωaragonite, rather than other environmental factors such as light and temperature. These field observations provide sufficient data to hypothesize that there is a seasonal "Carbonate Chemistry Coral Reef Ecosystem Feedback" (CREF hypothesis between the primary components of the reef ecosystem (i.e., scleractinian hard corals and macroalgae and seawater carbonate chemistry. In early summer, strong net autotrophy from benthic components of the reef system enhance [CO32-] and Ωaragonite conditions, and rates of coral calcification due to the photosynthetic uptake of CO2. In late summer, rates of coral calcification are suppressed by release of CO2 from reef metabolism during a period of strong net heterotrophy. It is likely that this seasonal CREF mechanism is present in other tropical reefs although attenuated compared to high-latitude reefs such as Bermuda. Due to lower annual mean surface seawater [CO32-] and Ωaragonite in Bermuda compared to tropical regions, we anticipate that Bermuda corals will experience seasonal periods

  17. Real-time feedback control using online attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy for continuous flow optimization and process knowledge.

    Science.gov (United States)

    Skilton, Ryan A; Parrott, Andrew J; George, Michael W; Poliakoff, Martyn; Bourne, Richard A

    2013-10-01

    The use of automated continuous flow reactors is described, with real-time online Fourier transform infrared spectroscopy (FT-IR) analysis to enable rapid optimization of reaction yield using a self-optimizing feedback algorithm. This technique has been applied to the solvent-free methylation of 1-pentanol with dimethyl carbonate using a γ-alumina catalyst. Calibration of the FT-IR signal was performed using gas chromatography to enable quantification of yield over a wide variety of flow rates and temperatures. The use of FT-IR as a real-time analytical technique resulted in an order of magnitude reduction in the time and materials required compared to previous studies. This permitted a wide exploration of the parameter space to provide process understanding and validation of the optimization algorithms.

  18. Sensor Acquisition for Water Utilities: Survey, Down Selection Process, and Technology List

    Energy Technology Data Exchange (ETDEWEB)

    Alai, M; Glascoe, L; Love, A; Johnson, M; Einfeld, W

    2005-06-29

    The early detection of the biological and chemical contamination of water distribution systems is a necessary capability for securing the nation's water supply. Current and emerging early-detection technology capabilities and shortcomings need to be identified and assessed to provide government agencies and water utilities with an improved methodology for assessing the value of installing these technologies. The Department of Homeland Security (DHS) has tasked a multi-laboratory team to evaluate current and future needs to protect the nation's water distribution infrastructure by supporting an objective evaluation of current and new technologies. The LLNL deliverable from this Operational Technology Demonstration (OTD) was to assist the development of a technology acquisition process for a water distribution early warning system. The technology survey includes a review of previous sensor surveys and current test programs and a compiled database of relevant technologies. In the survey paper we discuss previous efforts by governmental agencies, research organizations, and private companies. We provide a survey of previous sensor studies with regard to the use of Early Warning Systems (EWS) that includes earlier surveys, testing programs, and response studies. The list of sensor technologies was ultimately developed to assist in the recommendation of candidate technologies for laboratory and field testing. A set of recommendations for future sensor selection efforts has been appended to this document, as has a down selection example for a hypothetical water utility.

  19. Research on improving outpatients' satisfaction by using "Intercept survey and feedback" method%探索应用“拦截调查和反馈”法提高门诊患者满意度的研究

    Institute of Scientific and Technical Information of China (English)

    刘卉; 夏春萍; 邹波; 王海银

    2013-01-01

    OBJECTIVE To explore approaches for improving out-patients' satisfaction and provide a scientific basis to build harmonious relationship between doctors and patients.METHODS "Intercept surveys and feedback" method was adopted and about 100 out-patients daily were randomly selected to be surveyed,timely feedback was given to relative department and rectify and reform was asked to be implemented.Indices such as satisfaction rate,satisfaction coefficient were used for analyzing.RESULTS 48 995 valid questionnaires were investigated from November 2009 to June 2011; the overall satisfaction rate was 93.70 percent.An upward trend was shown for the satisfaction rate (P =0.010 7) ; top five departments with high satisfaction rates were pediatrics,outpatient department,surgery,internal medicine,ambulatory surgery centers respectively.The attitude of medical providers was the largest proportion in the patient feedback and accounted 28.5 percents.CONCLUSION A rising trend is shown for outpatient satisfaction after using "Intercept surveys and feedback" method,quality of service is gradually improved and the management is further more perfect."Intercept surveys and feedback"method may be one effective method for improving outpatients' satisfaction.%目的 探索提高门诊患者满意度的方法,为建设和谐医患关系提供科学依据.方法 采用“拦截调查和反馈”法,每日随机抽取100名左右门诊病人开展问卷调查,并将结果及时反馈至相关部门并要求整改,分析采用满意率、满意系数等指标.结果 2009年11月~2011年6月,共调查有效问卷48 995份,总体满意率为93.70%.满意率呈波动上升趋势(P=0.010 7);满意度排在前5位的部门为儿科、门诊科室、外科、内科、日间手术中心.病人意见反馈中服务态度类比例最大,占28.5%.结论 采用“拦截调查和反馈”法后门诊病人满意度呈上升趋势,医院服务质量逐步提升,管理进一步完善.“拦截调

  20. Wetland eco-engineering: Measuring and modeling feedbacks of oxidation processes between plants and clay-rich material

    NARCIS (Netherlands)

    Saaltink, R.; Dekker, S.C.; Griffioen, J.; Wassen, M.J.

    2016-01-01

    Interest is growing in using soft sediment as a foundation in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here, dredging some of the clay-rich lake-bed sediment and using it to construct wetland will soon begin. Natural processes will be utilized during

  1. Wetland eco-engineering: measuring and modeling feedbacks of oxidation processes between plants and clay-rich material

    NARCIS (Netherlands)

    Saaltink, R.M.; Dekker, S.C.; Griffioen, J.; Wassen, M.J.

    2016-01-01

    Interest is growing in using soft sediment as a foundation in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here, dredging some of the clay-rich lake-bed sediment and using it to construct wetland will soon begin. Natural processes will be utilized during

  2. Acute effects of alcohol on feedback processing and outcome evaluation during risky decision-making: an ERP study

    NARCIS (Netherlands)

    A.S. Euser (Anja); C.S. Meel (Catharine); M. Snelleman (Michelle); I.H.A. Franken (Ingmar)

    2011-01-01

    textabstractRationale: Although risky decision-making is one of the hallmarks of alcohol use disorders, relatively little is known about the acute psychopharmacological effects of alcohol on decision-making processes. Objective: The present study investigated the acute effects of alcohol on neural m

  3. The M-Wright function in time-fractional diffusion processes: a tutorial survey

    CERN Document Server

    Mainardi, Francesco; Pagnini, Gianni

    2010-01-01

    In the present review we survey the properties of a transcendental function of the Wright type, nowadays known as M-Wright function, entering as a probability density in a relevant class of self-similar stochastic processes that we generally refer to as time-fractional diffusion processes. Indeed, the master equations governing these processes generalize the standard diffusion equation by means of time-integral operators interpreted as derivatives of fractional order. When these generalized diffusion processes are properly characterized with stationary increments, the M-Wright function is shown to play the same key role as the Gaussian density in the standard and fractional Brownian motions. Furthermore, these processes provide stochastic models suitable for describing phenomena of anomalous diffusion of both slow and fast type.

  4. Natural language processing-based COTS software and related technologies survey.

    Energy Technology Data Exchange (ETDEWEB)

    Stickland, Michael G.; Conrad, Gregory N.; Eaton, Shelley M.

    2003-09-01

    Natural language processing-based knowledge management software, traditionally developed for security organizations, is now becoming commercially available. An informal survey was conducted to discover and examine current NLP and related technologies and potential applications for information retrieval, information extraction, summarization, categorization, terminology management, link analysis, and visualization for possible implementation at Sandia National Laboratories. This report documents our current understanding of the technologies, lists software vendors and their products, and identifies potential applications of these technologies.

  5. Review: “Implementation of Feedforward and Feedback Neural Network for Signal Processing Using Analog VLSI Technology”

    Directory of Open Access Journals (Sweden)

    Miss. Rachana R. Patil

    2015-01-01

    Full Text Available Main focus of project is on implementation of Neural Network Architecture (NNA with on chip learning on Analog VLSI Technology for signal processing application. In the proposed paper the analog components like Gilbert Cell Multiplier (GCM, Neuron Activation Function (NAF are used to implement artificial NNA. Analog components used comprises of multiplier, adder and tan sigmoidal function circuit using MOS transistor. This Neural Architecture is trained using Back Propagation (BP Algorithm in analog domain with new techniques of weight storage. Layout design and verification of above design is carried out using VLSI Backend Microwind 3.1 software Tool. The technology used to design layout is 32 nm CMOS Technology

  6. Global Positioning System (GPS) survey of Augustine Volcano, Alaska, August 3-8, 2000: data processing, geodetic coordinates and comparison with prior geodetic surveys

    Science.gov (United States)

    Pauk, Benjamin A.; Power, John A.; Lisowski, Mike; Dzurisin, Daniel; Iwatsubo, Eugene Y.; Melbourne, Tim

    2001-01-01

    Between August 3 and 8,2000,the Alaska Volcano Observatory completed a Global Positioning System (GPS) survey at Augustine Volcano, Alaska. Augustine is a frequently active calcalkaline volcano located in the lower portion of Cook Inlet (fig. 1), with reported eruptions in 1812, 1882, 1909?, 1935, 1964, 1976, and 1986 (Miller et al., 1998). Geodetic measurements using electronic and optical surveying techniques (EDM and theodolite) were begun at Augustine Volcano in 1986. In 1988 and 1989, an island-wide trilateration network comprising 19 benchmarks was completed and measured in its entirety (Power and Iwatsubo, 1998). Partial GPS surveys of the Augustine Island geodetic network were completed in 1992 and 1995; however, neither of these surveys included all marks on the island.Additional GPS measurements of benchmarks A5 and A15 (fig. 2) were made during the summers of 1992, 1993, 1994, and 1996. The goals of the 2000 GPS survey were to:1) re-measure all existing benchmarks on Augustine Island using a homogeneous set of GPS equipment operated in a consistent manner, 2) add measurements at benchmarks on the western shore of Cook Inlet at distances of 15 to 25 km, 3) add measurements at an existing benchmark (BURR) on Augustine Island that was not previously surveyed, and 4) add additional marks in areas of the island thought to be actively deforming. The entire survey resulted in collection of GPS data at a total of 24 sites (fig. 1 and 2). In this report we describe the methods of GPS data collection and processing used at Augustine during the 2000 survey. We use this data to calculate coordinates and elevations for all 24 sites surveyed. Data from the 2000 survey is then compared toelectronic and optical measurements made in 1988 and 1989. This report also contains a general description of all marks surveyed in 2000 and photographs of all new marks established during the 2000 survey (Appendix A).

  7. [Work process and working conditions in poultry processing plants: report of a survey on occupational health surveillance].

    Science.gov (United States)

    Oliveira, Paulo Antonio Barros; Mendes, Jussara Maria Rosa

    2014-12-01

    This article presents the report of a survey on health surveillance activities performed in poultry processing plants in the south of Brazil. It aims to contribute to an understanding of the work process developed, the growth of the sector, the organization of labor and the confrontation with the economic model of this sector, which has been exposing employees to working conditions that undermine their health. The working conditions identified are considered largely incompatible with health and human dignity. The study supports interinstitutional intervention, especially with the Public Ministry of Labor, criticizes the weak implementation of specific government interventions in health conditions in the industry and introduces the new Regulatory Standard 36 as a positive perspective for the near future.

  8. Feedback between tidal hydrodynamics and morphological changes induced by natural process and human interventions in a wave-dominated tidal inlet: Xiaohai, Hainan, China

    Institute of Scientific and Technical Information of China (English)

    GONG Wenping; SHEN Jian; JIA Jianjun

    2009-01-01

    The feedback between morphological evolution and tidal hydrodynamics in a wave-dominated tidal inlet, Xiaohai, China is investigated through data analysis and numerical model experiments. His-torically, Xiaohai Inlet had two openings, located at the north and south of Neizhi Island (a rocky outcrop), respectively. The evolution of Xiaohai Inlet was dominated by the natural process be-fore 1972. In addition to the natural process, human interventions, including the closure of the north opening, 50% of freshwater reduction, and increase of land reclamation, have altered tidal hydrodynamics and morphological evolution since 1972. A series of numerical model simulations were conducted to investigate the influence of morphological changes on the hydrodynamics and the influence of human activities on the inlet evolution. The natural process has caused narrowing and shoaling of the inlet throat, development of the flood-tidal delta, and shoaling of the tidal channel inside the lagoon. Human interventions have accelerated these changes. Consequently, the tidal propagation from the offshore into the lagoon has been impeded and the tidal energy has been dissipated substantially. Tidal current has changed from ebb-dominant to flood-dominant in most parts of the inlet system whereas the inlet throat has remained as ebb-dominant, the tidal prism has decreased consistently, and sediment has continued to deposit inside the inlet. As a result, the changes of morphology, hydrodynamics, and sediment transport show a positive feedback. The human interventions have had both advantageous and adverse influences on the stability of the inlet. The closure of the North Opening has decreased the longshore sediment input to the inlet, and increased the tidal prism, ebb velocity, and sediment transport in the south opening, thus enhancing the inlet's stability. However, reducing the river discharge and landfill of the tidal flats has resulted in a decrease of the tidal prism, the ebb velocity

  9. New Approaches To Photometric Redshift Prediction Via Gaussian Process Regression In The Sloan Digital Sky Survey

    CERN Document Server

    Way, M J; Gazis, P R; Srivastava, A N

    2009-01-01

    Expanding upon the work of Way & Srivastava 2006 we demonstrate how the use of training sets of comparable size continue to make Gaussian Process Regression a competitive and in many ways a superior approach to that of Neural Networks and other least-squares fitting methods. This is possible via new matrix inversion techniques developed for Gaussian Processes that do not require that the kernel matrix be sparse. This development, combined with a neural-network kernel function appears to give superior results for this problem. We demonstrate that there appears to be a minimum number of training set galaxies needed to obtain the optimal fit when using our Gaussian Process Regression rank-reduction methods. We also find that morphological information included with many photometric surveys appears, for the most part, to make the photometric redshift evaluation slightly worse rather than better. This would indicate that morphological information simply adds noise from the Gaussian Process point of view. In add...

  10. Beyond feedback control: the interactive use of performance management systems. Implications for process innovation in Italian healthcare organizations.

    Science.gov (United States)

    Demartini, Chiara; Mella, Piero

    2014-01-01

    This paper shows how the use of performance management systems affects managers' perception of satisfaction, the effectiveness of the control system and the performance related to process innovation. An exploratory empirical research has been conducted on 85 managers operating in Italian healthcare organizations. Empirical findings put forward that the interactive--as opposed to diagnostic--use of performance management systems enhances managerial satisfaction with the control system and managerial perception of effectiveness. The present study then showed that it is not the control itself that is an obstacle to innovation in organizations in general (and in health organizations in particular) but the diagnostic use of the control mechanisms, which impedes the interaction between the control personnel and those subject to the control. Finally, this paper addresses managerial implications and further research avenues.

  11. 360-degree feedback for medical trainees

    DEFF Research Database (Denmark)

    Holm, Ellen; Holm, Kirsten; Sørensen, Jette Led

    2015-01-01

    In 360-degree feedback medical colleagues and collaborators give a trainee feedback by answering a questionnaire on behaviour of the trainee. The questionnaire may contain questions answered on a scale or/and they may contain open questions. The result from 360-degree feedback is used for formative...... feedback and assessment. In order to secure reliability 8-15 respondents are needed. It is a matter of discussion whether the respondents should be chosen by the trainee or by a third part, and if respondents should be anonymous. The process includes a feedback session with a trained supervisor....

  12. Feedback i den laegelige postgraduate uddannelse

    DEFF Research Database (Denmark)

    Rubak, Sune Leisgaard Mørck; Ipsen, Merete; Sørensen, Jette Led

    2008-01-01

    Feedback may be described as a process comprising communication of information and reactions to such communication. It has been defined as specific information about the difference between a trainee's observed performance and a given standard with the intent of achieving performance improvement....... Feedback is essential in medical education and has great implications for the educational climate. It has been shown that a common language regarding the principles of feedback has a sustained effect on quality and frequency of feedback. Further research is needed on feedback and educational climate...

  13. A survey of the ways master's level nursing students learn the research process.

    Science.gov (United States)

    Bower, F L; Timmons, M E

    1999-03-01

    Because of the need for advanced practice nurses to perform more outcome measurement, a survey was conducted in the fall of 1997 to determine how master's level students learned the research process. Three hundred four surveys were mailed to schools with master's programs, and 222 were returned for a return rate of 73%. Sixty-six percent of the programs surveyed required a thesis and/or a research project. However, there was great variation in the research projects. A comprehensive examination was used to measure research ability by 36 programs (16%), either in conjunction with a thesis or research project or alone. One hundred forty-six programs (66%) offered only one option, be it a thesis, research project, comprehensive examination, or the many other alternative activities described by respondents. Seventy-six programs (34%) offered a variety of options from which students could select. The major differences between the thesis and the research project were related to three issues: a) the nature of the supervision; b) whether the activity was an individual or group project; and c) the amount of participation of the students. Because of the variability of expectations and the ways students are taught research, it was recommended nurse educators determine whether master's level nurse graduates were prepared to conduct outcome measurement and whether the means used to teach the research process were effective considering that endeavor.

  14. A survey on the status of nutrition care process implementation in korean hospitals.

    Science.gov (United States)

    Kim, Eun Mi; Baek, Hee Joon

    2013-07-01

    The Nutrition Care Process (NCP), developed by the American Dietetic Association, is a significant issue to dietetic professionals in many countries and there are rising needs for NCP implementation in Korea. We surveyed clinical nutrition managers of Korean general hospitals regarding the perception of NCP, the status of NCP implementation, and the opinions on NCP. The questionnaire was collected from 35 hospitals. Most clinical nutrition managers perceived NCP, but NCP implementation in hospital was at early stage. NCP was implemented in a fourth of the surveyed hospitals and many clinical nutrition managers responded that the lack of knowledge and the concern on increasing working time were major barriers to implementing NCP. To successfully implement NCP in Korean hospital, ongoing education and training programs should be developed to provide adequate knowledge and help dietitians to cope with the barriers.

  15. Data Processing Procedures and Methodology for Estimating Trip Distances for the 1995 American Travel Survey (ATS)

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, H.-L.; Rollow, J.

    2000-05-01

    The 1995 American Travel Survey (ATS) collected information from approximately 80,000 U.S. households about their long distance travel (one-way trips of 100 miles or more) during the year of 1995. It is the most comprehensive survey of where, why, and how U.S. residents travel since 1977. ATS is a joint effort by the U.S. Department of Transportation (DOT) Bureau of Transportation Statistics (BTS) and the U.S. Department of Commerce Bureau of Census (Census); BTS provided the funding and supervision of the project, and Census selected the samples, conducted interviews, and processed the data. This report documents the technical support for the ATS provided by the Center for Transportation Analysis (CTA) in Oak Ridge National Laboratory (ORNL), which included the estimation of trip distances as well as data quality editing and checking of variables required for the distance calculations.

  16. Effects of Web-Based Feedback on Students' Learning

    Science.gov (United States)

    van Kol, Simone; Rietz, Christian

    2016-01-01

    Feedback plays an important role in supporting students' learning process. Nonetheless, providing feedback is still rather unusual in higher education. Moreover, research on the design of ideal feedback as well as its effects is rare. In order to contribute to the development of this field, a web-based feedback system was implemented in a lecture…

  17. Enacting Feedback Utilization from a Task-Specific Perspective

    Science.gov (United States)

    Lam, Ricky

    2017-01-01

    Feedback is central to successful teaching and learning. Despite extensive research on the relationship between feedback, pedagogy and learning, there remain no conclusive answers as to how feedback can be effectively utilized by learners. Recently, there is emerging research exploring how feedback is conceptualized as dialogic processes to…

  18. Rethinking Feedback Practices in Higher Education: A Peer Review Perspective

    Science.gov (United States)

    Nicol, David; Thomson, Avril; Breslin, Caroline

    2014-01-01

    Peer review is a reciprocal process whereby students produce feedback reviews on the work of peers and receive feedback reviews from peers on their own work. Prior research has primarily examined the learning benefits that result from the receipt of feedback reviews, with few studies specifically exploring the merits of producing feedback reviews…

  19. Investing in the Future by Learning from the Past: Developing a Survey Tool to Gather Feedback from Deployed Army Forward Surgical Team

    Science.gov (United States)

    2007-11-02

    evaluated (Esposito, Kuby , Unfred, & Gamelli, 1995) . Southern Ohio Medical Center (SOMC) uses scaled surveys to gather statistically relevant...Esposito, T., Kuby , A., Unfred, C., & Gamelli, R. (1995). General surgeons and the advanced trauma life support course: is it time to re-focus? The Journal

  20. Innovation indicators: a survey of innovative activities in the international food processed industry

    Directory of Open Access Journals (Sweden)

    Vinicius Cardoso de Barros Fornari

    2015-02-01

    Full Text Available This paper seeks to combine traditional methods of measuring intensity with other alternative indicators to examine the dispersion of innovation activities in different industries and countries. The hypothesis that underlies the study lies in the fact that in the Food Processed Industry (IAP the traditional methods are insufficient to detect the core of the innovation process. As method, we analyzed patent data extracted from the twenty-five largest food processed companies in the world and suggested different indicators developed from the Pesquisa de Inovação Tecnológica (PINTEC, 2010 – for Brazilian companies – and the Community Innovation Survey (CIS, 2009 – for European Union companies. The results allowed us to establish relationships in three dimensions: (i the complexity of the innovative effort of the IAP; (ii the efforts to innovation in different countries are distinct and; (iii there is heterogeneity in country performance.

  1. Accounting Students' Feedback on Feedback in Australian Universities: They're Less than Impressed

    Science.gov (United States)

    Watty, Kim; de Lange, Paul; Carr, Rodney; O'Connell, Brendan; Howieson, Bryan; Jacobsen, Ben

    2013-01-01

    Undergraduate accounting students in Australian universities are dissatisfied with the feedback that they currently receive. Recent evidence from the Course Experience Questionnaire (CEQ, a national survey of Australian university graduates) suggests that the accounting discipline ranks poorly on assessment feedback when compared to other…

  2. Innovation in healthcare team feedback.

    Science.gov (United States)

    Plaza, Christine; Beard, Leslie; Fonzo, Anthony Di; Tommaso, Michael Di; Mujawaz, Yaman; Serra-Julia, Marcel; Morra, Dante

    2011-01-01

    Healthcare delivery is evolving from individual, autonomous practice to collaborative team practice. However, barriers such as professional autonomy, time constraints and the perception of error as failure preclude learning behaviours that can facilitate organizational learning and improvement. Although experimentation, engaging in questions and feedback, discussing errors and reflecting on results can facilitate learning and promote effective performance, the cultural barriers within healthcare can prevent or inhibit this type of behaviour among teams. At the University Health Network's Centre for Innovation in Complex Care, we realize the need for a tool that facilitates learning behaviour and is sensitive to the risk-averse nature of the clinical environment. The vehicle for the Team Feedback Tool is a web-based application called Rypple (www.rypple.com), which allows team members to provide anonymous, rapid-fire feedback on team processes and performance. Rypple facilitates communication, elicits feedback and provokes discussion. The process enables follow-up face-to-face team discussions and encourages teams to create actionable solutions for incremental changes to enhance team health and performance. The Team Feedback Tool was implemented and piloted in general internal medicine at the University Health Network's Toronto General Hospital from early May 2009 to July 2009 to address the issues of teamwork and learning behaviour in the clinical environment. This article explores the opportunities and barriers associated with the implementation of the Team Feedback Tool.

  3. HIDE & SEEK: End-to-End Packages to Simulate and Process Radio Survey Data

    CERN Document Server

    Akeret, Joel; Chang, Chihway; Monstein, Christian; Amara, Adam; Refregier, Alexandre

    2016-01-01

    As several large radio surveys begin operation within the coming decade, a wealth of radio data will become available and provide a new window to the Universe. In order to fully exploit the potential of these data sets, it is important to understand the systematic effects associated with the instrument and the analysis pipeline. A common approach to tackle this is to forward-model the entire system - from the hardware to the analysis of the data products. For this purpose, we introduce two newly developed, open-source Python packages: the HI Data Emulator (HIDE) and the Signal Extraction and Emission Kartographer (SEEK) for simulating and processing radio survey data. HIDE forward-models the process of collecting astronomical radio signals in a single dish radio telescope instrument and outputs pixel-level time-ordered-data. SEEK processes the time-ordered-data, removes artifacts from Radio Frequency Interference (RFI), automatically applies flux calibration, and aims to recover the astronomical radio signal....

  4. Modeling the process leading to abortion: an application to French survey data.

    Science.gov (United States)

    Rossier, Clémentine; Michelot, François; Bajos, Nathalie

    2007-09-01

    In this study, we model women's recourse to induced abortion as resulting from a process that starts with sexual intercourse and contraceptive use (or nonuse), continues with the occurrence of an unintended pregnancy, and ends with the woman's decision to terminate the pregnancy and her access to abortion services. Our model includes two often-neglected proximate determinants of abortion: sexual practices and access to abortion services. We relate three sociodemographic characteristics--women's educational level, their relationship status, and their age--step by step to the stages of the abortion process. We apply our framework using data from the COCON survey, a national survey on reproductive health conducted in France in 2000. Our model shows that sociodemographic variables may have opposite impacts as the abortion process unfolds. For example, women's educational level can be positively linked to the probability of practicing contraception but negatively linked to the propensity to carry the unintended pregnancy to term. This conceptual framework brings together knowledge that is currently dispersed in the literature and helps to identify the source of abortion-rate differentials.

  5. Technologies for learner-centered feedback

    Directory of Open Access Journals (Sweden)

    Jane Costello

    2013-09-01

    Full Text Available As the number, type, and use of technologies to support learning increases, so do the opportunities for using these technologies for feedback. Learner-centered feedback is a core to the teaching-learning process. It is related to assessment in describing how learners perform in their learning, their gain in knowledge, skills, and attitudes. Feedback, types of feedback, guidelines for effective learner-centered feedback, and feedback’s relationship to assessment are presented. Methods of providing feedback, for example, automated, audio scribe pens, digital audio, etc., and the related technologies are described. Technologies that allow instructors to make informed decisions about the use of various methods for feedback are discussed.

  6. Advanced EMI models for survey data processing: targets detection and classification

    Science.gov (United States)

    Shubitidze, F.; Sigman, J. B.; Wang, Yinlin; Miller, J.; Keranen, J.; Shamatava, I.; Barrowes, B. E.; O'Neill, K.

    2014-06-01

    One of the most challenging aspects of survey data processing is target selection. The fundamental input for the classification is dynamic data collected along survey lines. These data are different from the static data obtained in cued mode and used for target classification. Survey data are typically collected using just one transmitter loop (the Z-axis loop) and feature short data point collection times and short decay transience. The collection intervals for each data point are typically 0.1 s, and the signal repetition rates are typically 90 or 270 Hz (in other words, the transient decay times are 2.7 ms or 0.9 ms). Reliable classification requires multiple side/angle illumination; i.e., to conduct reliable classification it is necessary to combine and jointly invert multiple data points. However, picking data points that provide optimal information for classifying targets is a difficult task. The traditional method plots signal amplitudes on a 2D map and picks peaks of signal level without properly accounting for the underlying physics. In this paper, the joint diagonalization is applied to survey data sets to improve data pre-processing and target picking. The JD technique is an EMI data analysis and target classification technique and is applicable for all next-generation multi-static array EMI sensors. The method extracts multi-static response data matrix eigenvalues. The eigenvalues are main characteristics of the data. Recent studies have demonstrated that the method has great potential to quickly estimate the number of potential targets and moreover classify these targets at the data pre-processing stage, in real time and without the need for a forward model. Another advantage of JD is that it provides the ability to separate signal from noise making it possible to de-noise data without distorting the signal due to the targets. In this paper the JD technique is used to process dynamic data collected at South West Proving Ground and Aberdeen Proving

  7. Geomorphic process from topographic form: automating the interpretation of repeat survey data in river valleys

    Science.gov (United States)

    Kasprak, Alan; Caster, Joshua J.; Bangen, Sara G.; Sankey, Joel B.

    2017-01-01

    The ability to quantify the processes driving geomorphic change in river valley margins is vital to geomorphologists seeking to understand the relative role of transport mechanisms (e.g. fluvial, aeolian, and hillslope processes) in landscape dynamics. High-resolution, repeat topographic data are becoming readily available to geomorphologists. By contrasting digital elevation models derived from repeat surveys, the transport processes driving topographic changes can be inferred, a method termed ‘mechanistic segregation.’ Unfortunately, mechanistic segregation largely relies on subjective and time consuming manual classification, which has implications both for its reproducibility and the practical scale of its application. Here we present a novel computational workflow for the mechanistic segregation of geomorphic transport processes in geospatial datasets. We apply the workflow to seven sites along the Colorado River in the Grand Canyon, where geomorphic transport is driven by a diverse suite of mechanisms. The workflow performs well when compared to field observations, with an overall predictive accuracy of 84% across 113 validation points. The approach most accurately predicts changes due to fluvial processes (100% accuracy) and aeolian processes (96%), with reduced accuracy in predictions of alluvial and colluvial processes (64% and 73%, respectively). Our workflow is designed to be applicable to a diversity of river systems and will likely provide a rapid and objective understanding of the processes driving geomorphic change at the reach and network scales. We anticipate that such an understanding will allow insight into the response of geomorphic transport processes to external forcings, such as shifts in climate, land use, or river regulation, with implications for process-based river management and restoration.

  8. Error and feedback processing in children with ADHD and children with Autistic Spectrum Disorder : An EEG event-related potential study

    NARCIS (Netherlands)

    Groen, Yvonne; Wijers, Albertus A.; Mulder, Lambertus J. M.; Waggeveld, Brenda; Minderaa, Ruud B.; Althaus, Monika

    2008-01-01

    Objective: Performance monitoring was investigated in typically developing (TD) children, children with Autistic Spectrum Disorder (ASD), and Methylphenidate (Mph)-treated and medication-free children with Attention Deficit Hyperactivity Disorder (ADHD). Methods: Subjects performed a feedback-based

  9. The Role of Character in the Hiring Process: A Pilot Study Survey of College Seniors' Potential Employers

    Science.gov (United States)

    Firmin, Michael; Proemmel, Elizabeth; McDivitt, Sarah; Evens, Jennifer; Gibbs, Lew

    2009-01-01

    We surveyed 31 prospective employers (65% response rate) regarding their views on character as part of the employment selection process. The results showed character qualities superordinate, relative to skills that prospective employees bring to potential jobs. We discuss survey results in light of business educators' responsibility for helping…

  10. A survey of artifact-simulation approaches from the perspective of application to use processes of consumer durables

    NARCIS (Netherlands)

    Van der Vegte, W.F.

    2006-01-01

    In this paper, approaches for artifact-behavior simulation are reviewed. The motivation behind the survey is to explore available knowledge for the development of a new form of computer support for conceptual design to simulate use processes of consumer durables. The survey covers the simulation of

  11. 77 FR 33253 - Regulatory Guide 8.24, Revision 2, Health Physics Surveys During Enriched Uranium-235 Processing...

    Science.gov (United States)

    2012-06-05

    ... COMMISSION Regulatory Guide 8.24, Revision 2, Health Physics Surveys During Enriched Uranium-235 Processing... CONTACT: Gregory Chapman, Uranium Enrichment Branch, Division of Fuel Cycle Safety and Safeguards, Office.... Introduction Revision 2 of Regulatory Guide 8.24, ``Health Physics Surveys During Enriched...

  12. HIDE & SEEK: End-to-end packages to simulate and process radio survey data

    Science.gov (United States)

    Akeret, J.; Seehars, S.; Chang, C.; Monstein, C.; Amara, A.; Refregier, A.

    2017-01-01

    As several large single-dish radio surveys begin operation within the coming decade, a wealth of radio data will become available and provide a new window to the Universe. In order to fully exploit the potential of these datasets, it is important to understand the systematic effects associated with the instrument and the analysis pipeline. A common approach to tackle this is to forward-model the entire system-from the hardware to the analysis of the data products. For this purpose, we introduce two newly developed, open-source Python packages: the HI Data Emulator (HIDE) and the Signal Extraction and Emission Kartographer (SEEK) for simulating and processing single-dish radio survey data. HIDE forward-models the process of collecting astronomical radio signals in a single-dish radio telescope instrument and outputs pixel-level time-ordered-data. SEEK processes the time-ordered-data, removes artifacts from Radio Frequency Interference (RFI), automatically applies flux calibration, and aims to recover the astronomical radio signal. The two packages can be used separately or together depending on the application. Their modular and flexible nature allows easy adaptation to other instruments and datasets. We describe the basic architecture of the two packages and examine in detail the noise and RFI modeling in HIDE, as well as the implementation of gain calibration and RFI mitigation in SEEK. We then apply HIDE &SEEK to forward-model a Galactic survey in the frequency range 990-1260 MHz based on data taken at the Bleien Observatory. For this survey, we expect to cover 70% of the full sky and achieve a median signal-to-noise ratio of approximately 5-6 in the cleanest channels including systematic uncertainties. However, we also point out the potential challenges of high RFI contamination and baseline removal when examining the early data from the Bleien Observatory. The fully documented HIDE &SEEK packages are available at http://hideseek.phys.ethz.ch/ and are published

  13. The expeditious survey of soils as a management strategy against degradation processes of agroecosystems

    Science.gov (United States)

    Machado Siqueira, Glécio; Medeiros Bezerra, Joel

    2013-04-01

    The pressure for agricultural use in hilly areas regarded as marginal to the productive process, committed to carrying capacity of natural systems and exposes the available resources, especially soil and water with higher rates of degradation. This fact, coupled with the lack of planning of production activities, knowing the limitations and capabilities of environmental elements, as well as the use of inappropriate agricultural practices and intensive, quickened the processes that generate environmental imbalance. To circumvent these problems, it is necessary to find mechanisms that mitigate the conflicts generated between productive activities and the environment. One should then respect the specificities and restrictions local soil and their interactions with other components of the environment, trying to select and adapt agricultural practices and techniques best suited to local conditions and enabling the sustainable use of land. For this detailed information and appropriate scale, consistent with the need for rural communities become indispensable instrument to support the management of natural resource use. The expeditious survey of soil provides subsidies to use planning and land management and propose management strategies that ensure higher productivity of soils and maintenance of the environmental quality of the area in question, so as to eliminate or at least alleviate the problems of erosion soil. The joint use of land mapping and topographical and use and occupancy permits integrated management for the recovery of degraded areas, the use of soil conservation practices and indicating areas for reforestation, agriculture and pasture. Thus, this study aims to evaluate the use of GIS tools for improving the expeditious survey of soil. The present study was conducted using data from the municipality of Campo do Meio (Minas Gerais, Brazil). Were prepared soil maps, topography and land use and occupation. Later he was made a map of land use capability (FAO

  14. Comparisons, processing and interpretation of the surveyed data by GMS-06 and other magnetotelluric sounding systems

    Institute of Scientific and Technical Information of China (English)

    YU Peng; WU Jian-sheng; WANG Jia-lin; ZHANG Xin-bing

    2006-01-01

    @@ In recent years, the data collecting and processing of magnetotelluric sounding (MT) have progressed greatly.How to improve the quality of field surveyed data and obtain the high quality parameters such as apparent resistivity and phase is the most important link during the overall flow. It is closely related to the signal-to-noise ratio of magnetic sensors, the resolution of data collecting units and relevant processing methods as well. Produced by Germany Metronix Measurement Instruments and Electronics Ltd., the new type multi-channel geophysical measurement system GMS-06 was already adopted and used by domestic units such as Institute of Geology and Geophysics of Chinese Academy of Sciences and Tongji University.

  15. The Endogenous Feedback Network

    DEFF Research Database (Denmark)

    Augustenborg, Claudia Carrara

    2010-01-01

    proposals, it will first be considered the extents of their reciprocal compatibility, tentatively shaping an integrated, theoretical profile of consciousness. A new theory, the Endogenous Feedback Network (EFN) will consequently be introduced which, beside being able to accommodate the main tenets...... of the reviewed theories, appears able to compensate for the explanatory gaps they leave behind. The EFN proposes consciousness as the phenomenon emerging from a distinct network of neural paths broadcasting the neural changes associated to any mental process. It additionally argues for the need to include a 5th...

  16. Models of AGN feedback

    CERN Document Server

    Combes, F

    2014-01-01

    The physical processes responsible of sweeping up the surrounding gas in the host galaxy of an AGN, and able in some circumstances to expel it from the galaxy, are not yet well known. The various mechanisms are briefly reviewed: quasar or radio modes, either momentum-conserving outflows, energy-conserving outflows, or intermediate. They are confronted to observations, to know whether they can explain the M-sigma relation, quench the star formation or whether they can also provide some positive feedback and how the black hole accretion history is related to that of star formation.

  17. The Capital Budgeting Process of Healthcare Organizations: A Review of Surveys.

    Science.gov (United States)

    Mukherjee, Tarun; Rahahleh, Naseem Al; Lane, Walter

    2016-01-01

    Several surveys have been administered over the last 40 plus years to learn about capital budgeting practices of healthcare organizations. In this report, we analyze and synthesize these surveys in a four-stage framework of the capital budgeting process: identification, development, selections, and post-audit. We examine three issues in particular: (1) efficiency of for-profit hospitals relative to not-for-profit hospitals, (2) capital budgeting practices of the healthcare industry vis-à-vis other industries, and (3) effects of healthcare mergers and acquisitions on capital budgeting decisions. We found indirect evidence that for-profit hospitals exhibited greater efficiency than not-for-profit hospitals in recent years. The acquisition of not-for-profits by for-profits is credited as the primary reason for growth of multihospital systems; these acquisitions may have contributed to the more efficient capital budgeting practices. One unique attribute of healthcare is the dominant role of physicians in almost all aspects of the capital budgeting process. In agreement with some researchers, we conclude that the disproportionate influence of physicians is likely to impede efficient decision making in capital budgeting, especially for nonprofit organizations.

  18. Trends in the nursing doctoral comprehensive examination process: a national survey.

    Science.gov (United States)

    Mawn, Barbara E; Goldberg, Shari

    2012-01-01

    The doctoral comprehensive or qualifying examination (CE/QE) is a traditional rite of passage into the community of scholars for the nursing profession. This exploratory, descriptive cross-sectional study examined trends in the process, timing, and methodology of comprehensive and qualifying examinations in nursing doctoral programs in the United States. Administrators from 45 schools responded to an online survey from 27 states across the country (37% response rate). Participants reported wide variations in the process. The most common method of implementation was the written take-home test (47%), two thirds of which had a subsequent oral examination. Eleven survey respondents (24%) reported using a form of the traditional written, timed, on-site examination; however, only 4 of these also followed up with an oral defense. Nine schools (20%) moved to a requirement for a written publishable paper; three schools consider the written proposal and its defense as the CE/QE. Approximately half had changed their policy in the past 5 years. With the increase in nursing doctor of philosophy programs over the past decade, information is needed to facilitate the development of methods to achieve program outcomes. An understanding of national CE/QE trends can provide a starting point for discussion and allow innovative ideas to meet the need of individual programs. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. An Extended Validity Argument for Assessing Feedback Culture.

    Science.gov (United States)

    Rougas, Steven; Clyne, Brian; Cianciolo, Anna T; Chan, Teresa M; Sherbino, Jonathan; Yarris, Lalena M

    2015-01-01

    NEGEA 2015 CONFERENCE ABSTRACT (EDITED): Measuring an Organization's Culture of Feedback: Can It Be Done? Steven Rougas and Brian Clyne. CONSTRUCT: This study sought to develop a construct for measuring formative feedback culture in an academic emergency medicine department. Four archetypes (Market, Adhocracy, Clan, Hierarchy) reflecting an organization's values with respect to focus (internal vs. external) and process (flexibility vs. stability and control) were used to characterize one department's receptiveness to formative feedback. The prevalence of residents' identification with certain archetypes served as an indicator of the department's organizational feedback culture. New regulations have forced academic institutions to implement wide-ranging changes to accommodate competency-based milestones and their assessment. These changes challenge residencies that use formative feedback from faculty as a major source of data for determining training advancement. Though various approaches have been taken to improve formative feedback to residents, there currently exists no tool to objectively measure the organizational culture that surrounds this process. Assessing organizational culture, commonly used in the business sector to represent organizational health, may help residency directors gauge their program's success in fostering formative feedback. The Organizational Culture Assessment Instrument (OCAI) is widely used, extensively validated, applicable to survey research, and theoretically based and may be modifiable to assess formative feedback culture in the emergency department. Using a modified Delphi technique and several iterations of focus groups amongst educators at one institution, four of the original six OCAI domains (which each contain 4 possible responses) were modified to create a 16-item Formative Feedback Culture Tool (FFCT) that was administered to 26 residents (response rate = 55%) at a single academic emergency medicine department. The mean

  20. Sediment transport and erosional processes of a mountain bedrock channel using high-resolution topographic surveys

    Science.gov (United States)

    Yin, Yu-Hsuan; Shyu, J. Bruce H.

    2017-04-01

    In recent years, spatial information with high resolution and accuracy have become widely available, thanks to the rapid technological developments. Such data have been applied in a variety of topics, including the digitization and monitoring of outcrops and the construction of digital elevation models (DEMs) of landscapes. In fluvial geomorphology, it is critical to understand the sediment transport and erosional processes of bedrock channels, but previously this is generally done using computer numerical simulations or minimized experiments. Therefore, this study intends to observe in situ fluvial sediment transport and erosional processes using terrestrial laser scanning (also called "ground LiDAR") and structure-from-motion (SfM) photogrammetry in a mountain bedrock channel in eastern Taiwan. Along the Swallow Grotto (Yanzikou) section of the Liwu River, there are many large boulders with different sizes that are up to more than ten meters. Most of these boulders came from rock fall events of a nearby tributary, and are gneiss in composition, distinctively different from the bedrock of the river channel (marble). Thus in this study, we chose these boulders as our survey targets. We applied ground LiDAR survey to observe the movement of the boulders, and to understand the transportation threshold of sediments under different flow conditions. For those giant boulders that do not seem to be moveable under regular fluvial conditions, we suspect that bedrock erosional processes apply to them. We then used SfM photogrammetry to monitor the erosion of particular boulders. By constructing 3D models of the boulders before and after flooding events, we will be able to analyze the amount and location of erosion occurred on the boulders. Combining these different datasets and results, we hope to further understand the sediment transport and erosional processes of bedrock channels.

  1. Facilitating EFL Learners' Oral Communication through Effective Feedback

    Institute of Scientific and Technical Information of China (English)

    李俊芬

    2002-01-01

    Feedback is an indispensable component of teaching process.Research finding shows that one of the keys to successful language learning lies in the feedback learner receives from others.This paper proposed some solutions to feedback problems in oral communication of non-English majors.The author finds that feedback can work effectively only when learners willingly internalize teacher feedback after their affective filter.

  2. Collective irrationality and positive feedback.

    Directory of Open Access Journals (Sweden)

    Stamatios C Nicolis

    Full Text Available Recent experiments on ants and slime moulds have assessed the degree to which they make rational decisions when presented with a number of alternative food sources or shelter. Ants and slime moulds are just two examples of a wide range of species and biological processes that use positive feedback mechanisms to reach decisions. Here we use a generic, experimentally validated model of positive feedback between group members to show that the probability of taking the best of options depends crucially on the strength of feedback. We show how the probability of choosing the best option can be maximized by applying an optimal feedback strength. Importantly, this optimal value depends on the number of options, so that when we change the number of options the preference of the group changes, producing apparent "irrationalities". We thus reinterpret the idea that collectives show "rational" or "irrational" preferences as being a necessary consequence of the use of positive feedback. We argue that positive feedback is a heuristic which often produces fast and accurate group decision-making, but is always susceptible to apparent irrationality when studied under particular experimental conditions.

  3. Feedback control of coupled-bunch instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Fox, J.D.; Eisen, N.; Hindi, H.; Linscott, I.; Oxoby, G.; Sapozhnikov, L. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Serio, M. [Istituto Nazionale di Fisica Nucleare, Frascati (Italy). Lab. Nazionale di Frascati

    1993-05-01

    The next generation of synchrotron light sources and particle accelerators will require active feedback systems to control multi-bunch instabilities. Stabilizing hundreds or thousands of potentially unstable modes in these accelerator designs presents many technical challenges. Feedback systems to stabilize coupled-bunch instabilities may be understood in the frequency domain (mode-based feedback) or in the time domain (bunch-by-bunch feedback). In both approaches an external amplifier system is used to create damping fields that prevent coupled-bunch oscillations from growing without bound. The system requirements for transverse (betatron) and longitudinal (synchrotron) feedback are presented, and possible implementation options developed. Feedback system designs based on digital signal-processing techniques are described. Experimental results are shown from a synchrotron oscillation damper in the SSRL/SLAC storage ring SPEAR that uses digital signal-processing techniques.

  4. Effectiveness of Corrective Feedback on Writing

    Institute of Scientific and Technical Information of China (English)

    高砚

    2012-01-01

      This study aims to find out the effectiveness of corrective feedback on ESL writing. By reviewing and analyzing the previous six research studies, the author tries to reveal the most effective way to provide corrective feedback for L2 students and the factors that impact the processing of error feedback. Findings indicated that corrective feedback is helpful for students to improve ESL writing on both accuracy and fluency. Furthermore, correction and direct corrective feedbacks as well as the oral and written meta-linguistic explanation are the most effective ways to help students improving their writing. However, in⁃dividual learner’s difference has influence on processing corrective feedback. At last, limitation of present study and suggestion for future research were made.

  5. Fuzzy cloud concepts for assessing radiation feedbacks

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, H. [Univ. of Colorado, Boulder, CO (United States)

    1995-09-01

    The importance of clouds in the climate system is well-known but poorly understood. Modeling and observational studies have suggested that there may be positive feedbacks associated with certain cloud processes, but it is not known how strong these feedbacks are in the context of the overall system. Examples include ice microphysics feedback, as shown by Liou`s model, and the relationship between SST and cloud cover in the tropics, which is the focus of this research. 2 refs., 3 figs.

  6. Look who's judging-Feedback source modulates brain activation to performance feedback in social anxiety.

    Science.gov (United States)

    Peterburs, Jutta; Sandrock, Carolin; Miltner, Wolfgang H R; Straube, Thomas

    2016-06-01

    It is as yet unknown if behavioral and neural correlates of performance monitoring in socially anxious individuals are affected by whether feedback is provided by a person or a computer. This fMRI study investigated modulation of feedback processing by feedback source (person vs. computer) in participants with high (HSA) (N=16) and low social anxiety (LSA) (N=16). Subjects performed a choice task in which they were informed that they would receive positive or negative feedback from a person or the computer. Subjective ratings indicated increased arousal and anxiety in HSA versus LSA, most pronounced for social and negative feedback. FMRI analyses yielded hyperactivation in ventral medial prefrontal cortex (vmPFC)/anterior cingulate cortex (ACC) and insula for social relative to computer feedback, and in mPFC/ventral ACC for positive relative to negative feedback in HSA as compared to LSA. These activation patterns are consistent with increased interoception and self-referential processing in social anxiety, especially during processing of positive feedback. Increased ACC activation in HSA to positive feedback may link to unexpectedness of (social) praise as posited in social anxiety disorder (SAD) psychopathology. Activation in rostral ACC showed a reversed pattern, with decreased activation to positive feedback in HSA, possibly indicating altered action values depending on feedback source and valence. The present findings corroborate a crucial role of mPFC for performance monitoring in social anxiety.

  7. Fault Tolerant Feedback Control

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2001-01-01

    An architecture for fault tolerant feedback controllers based on the Youla parameterization is suggested. It is shown that the Youla parameterization will give a residual vector directly in connection with the fault diagnosis part of the fault tolerant feedback controller. It turns out...... that there is a separation be-tween the feedback controller and the fault tolerant part. The closed loop feedback properties are handled by the nominal feedback controller and the fault tolerant part is handled by the design of the Youla parameter. The design of the fault tolerant part will not affect the design...... of the nominal feedback con-troller....

  8. Student Feedback or ‘Students Hit Back’: in Search of Quality Feedback for Quality Teaching

    Directory of Open Access Journals (Sweden)

    Abdel Rahman Abdalla Salih

    2012-11-01

    Full Text Available Universities and colleges often administer student feedback surveys on teaching to elicit students’ views of how a particular course is taught and learned in order to improve teaching quality by helping tutors increase opportunities for better learning. This paper reports the views of (40 English teachers and (124 General Foundation Programme (GFP students on student feedback in institutions of higher education in the Sultanate of Oman, and the implications of such perceptions on the quality of teaching and learning English language. Findings reveal variation in the views held by both teachers and students about student feedback on teaching and learning experience. The study confirms the need for consistency between the perceptions of teachers and students on student feedback, and for training students on quality feedback and reflective learning. Keywords: Quality assurance, student feedback, teacher response, quality teaching, transformative reflection, teacher perception

  9. Audio Feedback to Physiotherapy Students for Viva Voce: How Effective Is "The Living Voice"?

    Science.gov (United States)

    Munro, Wendy; Hollingworth, Linda

    2014-01-01

    Assessment and feedback remains one of the categories that students are least satisfied with within the United Kingdom National Student Survey. The Student Charter promotes the use of various formats of feedback to enhance student learning. This study evaluates the use of audio MP3 as an alternative feedback mechanism to written feedback for…

  10. Audio Feedback to Physiotherapy Students for Viva Voce: How Effective Is "The Living Voice"?

    Science.gov (United States)

    Munro, Wendy; Hollingworth, Linda

    2014-01-01

    Assessment and feedback remains one of the categories that students are least satisfied with within the United Kingdom National Student Survey. The Student Charter promotes the use of various formats of feedback to enhance student learning. This study evaluates the use of audio MP3 as an alternative feedback mechanism to written feedback for…

  11. Current feedback operational amplifiers and their applications

    CERN Document Server

    Senani, Raj; Singh, A K; Singh, V K

    2013-01-01

    This book describes a variety of current feedback operational amplifier (CFOA) architectures and their applications in analog signal processing/generation. Coverage includes a comprehensive survey of commercially available, off-the-shelf integrated circuit CFOAs, as well as recent advances made on the design of CFOAs, including design innovations for bipolar and CMOS CFOAs.  This book serves as a single-source reference to the topic, as well as a catalog of over 200 application circuits which would be useful not only for students, educators and researchers in apprising them about the recent developments in the area but would also serve as a comprehensive repertoire of useful circuits for practicing engineers who might be interested in choosing an appropriate CFOA-based topology for use in a given application.

  12. Insights from a refined decomposition of cloud feedbacks

    Science.gov (United States)

    Zelinka, Mark D.; Zhou, Chen; Klein, Stephen A.

    2016-09-01

    Decomposing cloud feedback into components due to changes in several gross cloud properties provides valuable insights into its physical causes. Here we present a refined decomposition that separately considers changes in free tropospheric and low cloud properties, better connecting feedbacks to individual governing processes and avoiding ambiguities present in a commonly used decomposition. It reveals that three net cloud feedback components are robustly nonzero: positive feedbacks from increasing free tropospheric cloud altitude and decreasing low cloud cover and a negative feedback from increasing low cloud optical depth. Low cloud amount feedback is the dominant contributor to spread in net cloud feedback but its anticorrelation with other components damps overall spread. The ensemble mean free tropospheric cloud altitude feedback is roughly 60% as large as the standard cloud altitude feedback because it avoids aliasing in low cloud reductions. Implications for the "null hypothesis" climate sensitivity from well-understood and robustly simulated feedbacks are discussed.

  13. [Sampling plan, weighting process and design effects of the Brazilian Oral Health Survey].

    Science.gov (United States)

    Silva, Nilza Nunes da; Roncalli, Angelo Giuseppe

    2013-12-01

    To present aspects of the sampling plan of the Brazilian Oral Health Survey (SBBrasil Project). with theoretical and operational issues that should be taken into account in the primary data analyses. The studied population was composed of five demographic groups from urban areas of Brazil in 2010. Two and three stage cluster sampling was used. adopting different primary units. Sample weighting and design effects (deff) were used to evaluate sample consistency. In total. 37,519 individuals were reached. Although the majority of deff estimates were acceptable. some domains showed distortions. The majority (90%) of the samples showed results in concordance with the precision proposed in the sampling plan. The measures to prevent losses and the effects the cluster sampling process in the minimum sample sizes proved to be effective for the deff. which did not exceeded 2. even for results derived from weighting. The samples achieved in the SBBrasil 2010 survey were close to the main proposals for accuracy of the design. Some probabilities proved to be unequal among the primary units of the same domain. Users of this database should bear this in mind, introducing sample weighting in calculations of point estimates, standard errors, confidence intervals and design effects.

  14. Medical Student Perceptions of Feedback and Feedback Behaviors Within the Context of the "Educational Alliance".

    Science.gov (United States)

    Bowen, Lucy; Marshall, Michelle; Murdoch-Eaton, Deborah

    2017-09-01

    Using the "educational alliance" as a conceptual framework, the authors explored medical students' beliefs about feedback and how their feedback behaviors reflect their perceptions. Five focus groups (four to six medical students each) at one UK medical school in 2015 were used to capture and elucidate learners' feedback perceptions and behaviors within the context of the learner-educator relationship. A map of key feedback opportunities across the program was used as a tool for exploring student engagement with the feedback process. Qualitative data were analyzed using an approach based on grounded theory principles. Three learner feedback behaviors emerged: recognizing, using, and seeking feedback. Five core themes influencing these behaviors were generated: learner beliefs, attitudes, and perceptions; relationships; teacher attributes; mode of feedback; and learning culture. Conceptual models illustrating the relationships between the themes and each behavior were developed. Learning culture influenced all three behaviors with a wide context of influences. Ensuring that feedback leads to improved performance requires more than training educators in best practices. The conceptual models support the educational alliance framework and illustrate the context and complexity of learning culture surrounding the educational relationship, learner, and feedback exchange. The educational alliance approach is underpinned by a mutual understanding of purpose and responsibility. Enhancing learners' feedback literacy skills seems to be the key aspect of the educational alliance in need of attention. Empowering learners to recognize, seek, and use feedback received within diverse learning cultures is essential.

  15. A survey of the baseline correction algorithms for real-time spectroscopy processing

    Science.gov (United States)

    Liu, Yuanjie; Yu, Yude

    2016-11-01

    In spectroscopy data analysis, such as Raman spectra, X-ray diffraction, fluorescence and etc., baseline drift is a ubiquitous issue. In high speed testing which generating huge data, automatic baseline correction method is very important for efficient data processing. We will survey the algorithms from classical Shirley background to state-of-the-art methods to present a summation for this specific field. Both advantages and defects of each algorithm are scrutinized. To compare the algorithms with each other, experiments are also carried out under SVM gap gain criteria to show the performance quantitatively. Finally, a rank table of these methods is built and the suggestions for practical choice of adequate algorithms is provided in this paper.

  16. Improving GPR Surveys Productivity by Array Technology and Fully Automated Processing

    Science.gov (United States)

    Morello, Marco; Ercoli, Emanuele; Mazzucchelli, Paolo; Cottino, Edoardo

    2016-04-01

    The realization of network infrastructures with lower environmental impact and the tendency to use digging technologies less invasive in terms of time and space of road occupation and restoration play a key-role in the development of communication networks. However, pre-existing buried utilities must be detected and located in the subsurface, to exploit the high productivity of modern digging apparatus. According to SUE quality level B+ both position and depth of subsurface utilities must be accurately estimated, demanding for 3D GPR surveys. In fact, the advantages of 3D GPR acquisitions (obtained either by multiple 2D recordings or by an antenna array) versus 2D acquisitions are well-known. Nonetheless, the amount of acquired data for such 3D acquisitions does not usually allow to complete processing and interpretation directly in field and in real-time, thus limiting the overall efficiency of the GPR acquisition. As an example, the "low impact mini-trench "technique (addressed in ITU - International Telecommunication Union - L.83 recommendation) requires that non-destructive mapping of buried services enhances its productivity to match the improvements of new digging equipment. Nowadays multi-antenna and multi-pass GPR acquisitions demand for new processing techniques that can obtain high quality subsurface images, taking full advantage of 3D data: the development of a fully automated and real-time 3D GPR processing system plays a key-role in overall optical network deployment profitability. Furthermore, currently available computing power suggests the feasibility of processing schemes that incorporate better focusing algorithms. A novel processing scheme, whose goal is the automated processing and detection of buried targets that can be applied in real-time to 3D GPR array systems, has been developed and fruitfully tested with two different GPR arrays (16 antennas, 900 MHz central frequency, and 34 antennas, 600 MHz central frequency). The proposed processing

  17. Unpacking Student Feedback as a Basis for Metacognition and Mediated Learning Experiences: A Socio-cultural perspective

    Directory of Open Access Journals (Sweden)

    Edmore Mutekwe

    2014-11-01

    Full Text Available The study examines the effects of the feedback given to students by lecturers as learning support. It was conducted with undergraduates in an educational theory course in a South African university. The thesis was that although some of the feedback messages transmitted to students regarding strengths and weaknesses in learning get easily decoded and turned into action to improve performance, some messages are misconstrued by the students making the process of giving feedback complex. Data was collected through a cross-sectional feedback survey utilizing focus group interviews with 50 Bachelor of Education pre-service students conveniently sampled. The data analysis followed a thematic approach with superordinate themes used to structure the discussion of findings. The study found that student feedback needs to be culturally responsive for it to foster metacognition in them. The conclusion was that unless lecturers provide feedback that is simple, meaningful and clearly focused, students are unlikely to take much heed of it as there is a general tendency to focus more on the marks obtained than on the role of the feedback provided. This makes some students leave university under-prepared or half-baked in terms of providing student feedback on performance.

  18. Survey of processes for high temperature-high pressure gas purification. [52 references

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J.P.; Edwards, M.S.

    1978-11-01

    In order to ensure the optimum operating efficiency of a combined-cycle electric power generating system, it is necessary to provide gas treatment processes capable of operating at high temperatures (> 1000/sup 0/F) and high pressures (> 10 atm (absolute)). These systems will be required to condition the inlet stream to the gas turbine to suitable levels of gas purity (removal of particulate matter, sulfur, nitrogen, and alkali metal compounds) to be compatible with both environmental and machine constraints. A survey of the available and developmental processes for the removal of these various contaminant materials has been conducted. Based on the data obtained from a variety of sources, an analysis has been performed to evaluate the performance of a number of potential cleanup processes in view of the overall system needs. The results indicate that commercially available, reliable, and economically competitive hot-gas cleanup systems (for the removal of H/sub 2/S, particulate matter, alkali, and nitrogen compounds) capable of conditioning raw product gas to the levels required for turbine use will not be available for some time.

  19. Artificial Neural Networks for Processing Graphs with Application to Image Understanding: A Survey

    Science.gov (United States)

    Bianchini, Monica; Scarselli, Franco

    In graphical pattern recognition, each data is represented as an arrangement of elements, that encodes both the properties of each element and the relations among them. Hence, patterns are modelled as labelled graphs where, in general, labels can be attached to both nodes and edges. Artificial neural networks able to process graphs are a powerful tool for addressing a great variety of real-world problems, where the information is naturally organized in entities and relationships among entities and, in fact, they have been widely used in computer vision, f.i. in logo recognition, in similarity retrieval, and for object detection. In this chapter, we propose a survey of neural network models able to process structured information, with a particular focus on those architectures tailored to address image understanding applications. Starting from the original recursive model (RNNs), we subsequently present different ways to represent images - by trees, forests of trees, multiresolution trees, directed acyclic graphs with labelled edges, general graphs - and, correspondingly, neural network architectures appropriate to process such structures.

  20. Internal Medicine Residents' Perspectives on Receiving Feedback in Milestone Format.

    Science.gov (United States)

    Angus, Steven; Moriarty, John; Nardino, Robert J; Chmielewski, Amy; Rosenblum, Michael J

    2015-06-01

    In contrast to historical feedback, which was vague or provided residents' numerical scores without clear meaning, milestone-based feedback is focused on specific knowledge, skills, and behaviors that define developmental trajectory. It was anticipated that residents would welcome the more specific and actionable feedback provided by the milestone framework, but this has not been studied. We assessed internal medicine (IM) residents' perceptions of receiving feedback in the milestone framework, particularly assessing perception of the utility of milestone-based feedback compared to non-milestone-based feedback. We surveyed a total of 510 IM residents from 7 institutions. Survey questions assessed resident perception of milestone feedback in identifying strengths, weaknesses, and trajectory of professional development. Postgraduate years 2 and 3 (PGY-2 and PGY-3) residents were asked to compare milestones with prior methods of feedback. Of 510 residents, 356 (69.8%) responded. Slightly less than half of the residents found milestone-based feedback "extremely useful" or "very useful" in identifying strengths (44%), weaknesses (43%), specific areas for improvement (45%), and appropriate education progress (48%). Few residents found such feedback "not very useful" or "not at all useful" in these domains. A total of 51% of PGY-2 and PGY-3 residents agreed that receiving milestone-based feedback was more helpful than previous forms of feedback. IM residents are aware of the concepts of milestones, and half of the residents surveyed found milestone feedback more helpful than previous forms of feedback. More work needs to be done to understand how milestone-based feedback could be delivered more effectively to enhance resident development.

  1. Prefrontal cortex and striatal activation by feedback in Parkinson's disease

    NARCIS (Netherlands)

    Keitz, Martijn; Koerts, Janneke; Kortekaas, Rudie; Renken, Remco; de Jong, Bauke M.; Leenders, Klaus L.

    2008-01-01

    Positive feedbacks reinforce goal-directed behavior and evoke pleasure. in Parkinson's disease (PD) the striatal dysfunction impairs motor performance, but also may lead to decreased positive feedback (reward) processing. This study investigates two types of positive feedback processing (monetary fe

  2. Rateless feedback codes

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Koike-Akino, Toshiaki; Orlik, Philip

    2012-01-01

    This paper proposes a concept called rateless feedback coding. We redesign the existing LT and Raptor codes, by introducing new degree distributions for the case when a few feedback opportunities are available. We show that incorporating feedback to LT codes can significantly decrease both...... the coding overhead and the encoding/decoding complexity. Moreover, we show that, at the price of a slight increase in the coding overhead, linear complexity is achieved with Raptor feedback coding....

  3. Preventing Feedback Fizzle

    Science.gov (United States)

    Brookhart, Susan M.

    2012-01-01

    Feedback is certainly about saying or writing helpful, learning-focused comments. But that is only part of it. What happens beforehand? What happens afterward? Feedback that is helpful and learning-focused fits into a context. Before a teacher gives feedback, students need to know the learning target so they have a purpose for using the feedback…

  4. Technologies for Learner-Centered Feedback

    Science.gov (United States)

    Costello, Jane; Crane, Daph

    2013-01-01

    As the number, type, and use of technologies to support learning increases, so do the opportunities for using these technologies for feedback. Learner-centered feedback is a core to the teaching-learning process. It is related to assessment in describing how learners perform in their learning, their gain in knowledge, skills, and attitudes.…

  5. Charge pulse restorer for resistor feedback preamplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Hegyesi, G. [Hungarian Acad. of Sci. (Hungary). Inst. of Nucl. Res.; Lakatos, T. [Hungarian Acad. of Sci. (Hungary). Inst. of Nucl. Res.

    1995-03-15

    A simple circuit for cancelling the main pole of traditional resistor feedback preamplifier output signals has been designed. The resultant waveform is a series of step functions equivalent to the output of a pulsed feedback preamplifier. The advantage of such a preamplifier output signal is that its quantized samples can directly be processed by certain digital signal processors. ((orig.)).

  6. Charge pulse restorer for resistor feedback preamplifiers

    Science.gov (United States)

    Hegyesi, Gyula; Lakatos, Tamas

    1995-02-01

    A simple circuit for cancelling the main pole of traditional resistor feedback preamplifier output signals has been designed. The resultant waveform is a series of step functions equivalent to the output of a pulsed feedback preamplifier. The advantage of such a preamplifier output signal is that its quantized samples can directly be processed by certain digital signal processors.

  7. Feedback for Web-based Assignments.

    Science.gov (United States)

    Collis, Betty; De Boer, W.; Slotman, K.

    2001-01-01

    Discusses a concept used at the University of Twente based on increased flexibility in learning options and the active student in which there are assignments submitted and monitored via a Web-based course management system. Outlines conceptual aspects of feedback as part of the assessment process, particularly feedback supported by a Web-based…

  8. A multidimensional approach to assessing intervention fidelity in a process evaluation of audit and feedback interventions to reduce unnecessary blood transfusions: a study protocol.

    Science.gov (United States)

    Lorencatto, Fabiana; Gould, Natalie J; McIntyre, Stephen A; During, Camilla; Bird, Jon; Walwyn, Rebecca; Cicero, Robert; Glidewell, Liz; Hartley, Suzanne; Stanworth, Simon J; Foy, Robbie; Grimshaw, Jeremy M; Michie, Susan; Francis, Jill J

    2016-12-12

    In England, NHS Blood and Transplant conducts national audits of transfusion and provides feedback to hospitals to promote evidence-based practice. Audits demonstrate 20% of transfusions fall outside guidelines. The AFFINITIE programme (Development & Evaluation of Audit and Feedback INterventions to Increase evidence-based Transfusion practIcE) involves two linked, 2×2 factorial, cluster-randomised trials, each evaluating two theoretically-enhanced audit and feedback interventions to reduce unnecessary blood transfusions in UK hospitals. The first intervention concerns the content/format of feedback reports. The second aims to support hospital transfusion staff to plan their response to feedback and includes a web-based toolkit and telephone support. Interpretation of trials is enhanced by comprehensively assessing intervention fidelity. However, reviews demonstrate fidelity evaluations are often limited, typically only assessing whether interventions were delivered as intended. This protocol presents methods for assessing fidelity across five dimensions proposed by the Behaviour Change Consortium fidelity framework, including intervention designer-, provider- and recipient-levels. (1) Design: Intervention content will be specified in intervention manuals in terms of component behaviour change techniques (BCTs). Treatment differentiation will be examined by comparing BCTs across intervention/standard practice, noting the proportion of unique/convergent BCTs. (2) Training: draft feedback reports and audio-recorded role-play telephone support scenarios will be content analysed to assess intervention providers' competence to deliver manual-specified BCTs. (3) Delivery: intervention materials (feedback reports, toolkit) and audio-recorded telephone support session transcripts will be content analysed to assess actual delivery of manual-specified BCTs during the intervention period. (4) Receipt and (5) enactment: questionnaires, semi-structured interviews based on the

  9. Student Feedback of Career Development Workshops for Program Improvement

    Science.gov (United States)

    LeBeau, J. E.; Pressley, S. N.

    2016-12-01

    A number of techniques are employed each year to evaluate the effectiveness of and to identify opportunities for improvement in the Laboratory for Atmospheric Research (LAR) REU program at Washington State University. For example, information gathered from pre-/post-surveys and pre-/post-interviews provides information regarding students' perceptions and levels of experience with the scientific process, career and academic goals, and motivation for joining the REU program. Poster session rubrics assess students' abilities to summarize their experiences in a professional setting. Alumni surveys gauge former participants' perceptions of the REU experience. One seemingly simple and highly useful, but often less documented, component of the evaluation process for program improvement is the use of workshop feedback forms. Weekly workshops are designed to provide students with enhanced knowledge and skills in the area of atmospheric chemistry as well as research design skills, academic and career guidance, and presentation skills. According to previous years' evaluation reports, workshops are largely beneficial to students for learning new skills. Yet, students suggest a number of recommendations that may benefit any REU program, such as: providing slides beforehand to provide a framework for the upcoming workshop, having instructors speak in more student-friendly language, covering higher-level topics, and including more hands-on, instructor-guided practice during the workshops. Thus, workshop feedback forms provide meaningful feedback to increase learning outcomes and enhance the REU student experience. This presentation will offer ideas gathered from over five years of workshop feedback forms that, while somewhat specific to workshops offered for the LAR REU, can offer faculty and PIs insight into the student experience, enhancing their ability to improve programming and achieve greater learning outcomes.

  10. Feedback on Student Performance in the Workplace: The Role of Workplace Supervisors

    Science.gov (United States)

    Peach, Deborah; Ruinard, Deborah; Webb, Fleur

    2014-01-01

    This chapter highlights the importance of feedback in work-integrated learning (WIL), the key role of workplace supervisors, and the importance of continuous improvement in systems to support feedback processes. The paper proposes a definition of feedback and formative feedback, as well as approaches for providing industry feedback in WIL. It…

  11. Which characteristics of written feedback are perceived as stimulating students' reflective competence : an exploratory study

    NARCIS (Netherlands)

    Dekker, Hanke; Schonrock-Adema, Johanna; Snoek, Jos W.; van der Molen, Thys; Cohen-Schotanus, Janke

    2013-01-01

    Background: Teacher feedback on student reflective writing is recommended to improve learners' reflective competence. To be able to improve teacher feedback on reflective writing, it is essential to gain insight into which characteristics of written feedback stimulate students' reflection processes.

  12. Which characteristics of written feedback are perceived as stimulating students' reflective competence : an exploratory study

    NARCIS (Netherlands)

    Dekker, Hanke; Schonrock-Adema, Johanna; Snoek, Jos W.; van der Molen, Thys; Cohen-Schotanus, Janke

    2013-01-01

    Background: Teacher feedback on student reflective writing is recommended to improve learners' reflective competence. To be able to improve teacher feedback on reflective writing, it is essential to gain insight into which characteristics of written feedback stimulate students' reflection processes.

  13. Data Cleaning In Data Warehouse: A Survey of Data Pre-processing Techniques and Tools

    Directory of Open Access Journals (Sweden)

    Anosh Fatima

    2017-03-01

    Full Text Available A Data Warehouse is a computer system designed for storing and analyzing an organization's historical data from day-to-day operations in Online Transaction Processing System (OLTP. Usually, an organization summarizes and copies information from its operational systems to the data warehouse on a regular schedule and management performs complex queries and analysis on the information without slowing down the operational systems. Data need to be pre-processed to improve quality of data, before storing into data warehouse. This survey paper presents data cleaning problems and the approaches in use currently for preprocessing. To determine which technique of preprocessing is best in what scenario to improve the performance of Data Warehouse is main goal of this paper. Many techniques have been analyzed for data cleansing, using certain evaluation attributes and tested on different kind of data sets. Data quality tools such as YALE, ALTERYX, and WEKA have been used for conclusive results to ready the data in data warehouse and ensure that only cleaned data populates the warehouse, thus enhancing usability of the warehouse. Results of paper can be useful in many future activities like cleansing, standardizing, correction, matching and transformation. This research can help in data auditing and pattern detection in the data.

  14. Occupational injury proneness in Indian women: A survey in fish processing industries

    Directory of Open Access Journals (Sweden)

    Saha Asim

    2006-09-01

    Full Text Available Abstract A cross sectional survey was initiated to understand the frequency of occupational injury occurrence and the associated factors in the fish processing industries of western India involving 185 randomly selected women subjects. All the subjects were interviewed with the help of an interviewer-administered questionnaire to collect information regarding their personal, occupational and work related morbidity details (including details of occupational injuries. Logistic regression method was used to analyze the data in order to obtain the contribution of individual factors on occupational injuries. This study has shown that work related morbidity like blanching of hand (OR; 2.30, 95%CI; 1.12–4.74 and nature of job like grading (OR; 3.99, 95%CI; 1.41–11.27 and packing (OR; 5.68, 95%CI; 1.65–19.57 had a significant impact on injury causation. This study eventually concludes that apart from nature of job of fish processing workers occupational hazards prevailing in the work environment contribute significantly to the occurrence of work related injuries and prevention of such occupational hazards may help in protecting workers from occupational injuries also.

  15. A Survey of Stochastic Simulation and Optimization Methods in Signal Processing

    Science.gov (United States)

    Pereyra, Marcelo; Schniter, Philip; Chouzenoux, Emilie; Pesquet, Jean-Christophe; Tourneret, Jean-Yves; Hero, Alfred O.; McLaughlin, Steve

    2016-03-01

    Modern signal processing (SP) methods rely very heavily on probability and statistics to solve challenging SP problems. SP methods are now expected to deal with ever more complex models, requiring ever more sophisticated computational inference techniques. This has driven the development of statistical SP methods based on stochastic simulation and optimization. Stochastic simulation and optimization algorithms are computationally intensive tools for performing statistical inference in models that are analytically intractable and beyond the scope of deterministic inference methods. They have been recently successfully applied to many difficult problems involving complex statistical models and sophisticated (often Bayesian) statistical inference techniques. This survey paper offers an introduction to stochastic simulation and optimization methods in signal and image processing. The paper addresses a variety of high-dimensional Markov chain Monte Carlo (MCMC) methods as well as deterministic surrogate methods, such as variational Bayes, the Bethe approach, belief and expectation propagation and approximate message passing algorithms. It also discusses a range of optimization methods that have been adopted to solve stochastic problems, as well as stochastic methods for deterministic optimization. Subsequently, areas of overlap between simulation and optimization, in particular optimization-within-MCMC and MCMC-driven optimization are discussed.

  16. Quantum feedback channels

    CERN Document Server

    Bowen, G

    2002-01-01

    In classical information theory the capacity of a noisy communication channel cannot be increased by the use of feedback. In quantum information theory the no-cloning theorem means that noiseless copying and feedback of quantum information cannot be achieved. In this paper, quantum feedback is defined as the unlimited use of a noiseless quantum channel from receiver to sender. Given such quantum feedback, it is shown to provide no increase in the entanglement-assisted capacities of a noisy quantum channel, in direct analogy to the classical case. It is also shown that in various cases of non-assisted capacities, feedback can increase the capacity of many quantum channels.

  17. Optimising UAV topographic surveys processed with structure-from-motion: Ground control quality, quantity and bundle adjustment

    Science.gov (United States)

    James, M. R.; Robson, S.; d'Oleire-Oltmanns, S.; Niethammer, U.

    2017-03-01

    Structure-from-motion (SfM) algorithms greatly facilitate the production of detailed topographic models from photographs collected using unmanned aerial vehicles (UAVs). However, the survey quality achieved in published geomorphological studies is highly variable, and sufficient processing details are never provided to understand fully the causes of variability. To address this, we show how survey quality and consistency can be improved through a deeper consideration of the underlying photogrammetric methods. We demonstrate the sensitivity of digital elevation models (DEMs) to processing settings that have not been discussed in the geomorphological literature, yet are a critical part of survey georeferencing, and are responsible for balancing the contributions of tie and control points. We provide a Monte Carlo approach to enable geomorphologists to (1) carefully consider sources of survey error and hence increase the accuracy of SfM-based DEMs and (2) minimise the associated field effort by robust determination of suitable lower-density deployments of ground control. By identifying appropriate processing settings and highlighting photogrammetric issues such as over-parameterisation during camera self-calibration, processing artefacts are reduced and the spatial variability of error minimised. We demonstrate such DEM improvements with a commonly-used SfM-based software (PhotoScan), which we augment with semi-automated and automated identification of ground control points (GCPs) in images, and apply to two contrasting case studies - an erosion gully survey (Taroudant, Morocco) and an active landslide survey (Super-Sauze, France). In the gully survey, refined processing settings eliminated step-like artefacts of up to 50 mm in amplitude, and overall DEM variability with GCP selection improved from 37 to 16 mm. In the much more challenging landslide case study, our processing halved planimetric error to 0.1 m, effectively doubling the frequency at which changes in

  18. Wetland and Sensitive Species Survey Report for Y-12: Proposed Uranium Processing Facility (UPF)

    Energy Technology Data Exchange (ETDEWEB)

    Giffen, N.; Peterson, M.; Reasor, S.; Pounds, L.; Byrd, G.; Wiest, M. C.; Hill, C. C.

    2009-11-01

    This report summarizes the results of an environmental survey conducted at sites associated with the proposed Uranium Processing Facility (UPF) at the Y-12 National Security Complex in September-October 2009. The survey was conducted in order to evaluate potential impacts of the overall project. This project includes the construction of a haul road, concrete batch plant, wet soil storage area and dry soil storage area. The environmental surveys were conducted by natural resource experts at ORNL who routinely assess the significance of various project activities on the Oak Ridge Reservation (ORR). Natural resource staff assistance on this project included the collection of environmental information that can aid in project location decisions that minimize impacts to sensitive resource such as significant wildlife populations, rare plants and wetlands. Natural resources work was conducted in various habitats, corresponding to the proposed areas of impact. Thc credentials/qualifications of the researchers are contained in Appendix A. The proposed haul road traverses a number of different habitats including a power-line right-of-way. wetlands, streams, forest and mowed areas. It extends from what is known as the New Salvage Yard on the west to the Polaris Parking Lot on the east. This haul road is meant to connect the proposed concrete batch plant to the UPF building site. The proposed site of the concrete batch plant itself is a highly disturbed fenced area. This area of the project is shown in Fig. 1. The proposed Wet Soils Disposal Area is located on the north side of Bear Creek Road at the former Control Burn Study Area. This is a second growth arce containing thick vegetation, and extensive dead and down woody material. This area of the project is shown in Fig. 2. Thc dry soils storage area is proposed for what is currently known as the West Borrow Area. This site is located on the west side of Reeves Road south of Bear Creek Road. The site is an early successional

  19. Situated Formative Feedback

    DEFF Research Database (Denmark)

    Lukassen, Niels Bech; Wahl, Christian; Sorensen, Elsebeth Korsgaard

    2016-01-01

    This study addresses the conceptual challenge of providing students with good quality feedback to enhance student learning in an online community of practice (COP). The aim of the study is to identify feedback mechanisms in a virtual learning environment (VLE) and to create a full formative...... feedback episode (FFE) through an online dialogue. The paper argues that dialogue is crucial for student learning and that feedback is not only something the teacher gives to the student. Viewing good quality feedback as social, situated, formative, emphasis is put on the establishment of dialogue. We...... refer to this type of feedback as, Situated Formative Feedback (SFF). As a basis for exploring, identifying and discussing relevant aspects of SFF the paper analyses qualitative data from a Moodle dialogue. Data are embedded in the qualitative analytic program Nvivo and are analysed with a system...

  20. Feedback and Incentives

    DEFF Research Database (Denmark)

    Eriksson, Tor Viking; Poulsen, Anders; Villeval, Marie Claire

    2009-01-01

    This paper experimentally investigates the impact of different pay schemes and relative performance feedback policies on employee effort. We explore three feedback rules: no feedback on relative performance, feedback given halfway through the production period, and continuously updated feedback. We...... use two pay schemes, a piece rate and a tournament. We find that overall feedback does not improve performance. In contrast to the piece-rate pay scheme there is some evidence of positive peer effects in tournaments since the underdogs almost never quit the competition even when lagging significantly...... behind, and front runners do not slack off. But in both pay schemes relative performance feedback reduces the quality of the low performers' work; we refer to this as a "negative quality peer effect"....

  1. 少数民族学生汉语写作反馈有效性调查%A Survey of the Feedback Effectiveness of Chinese Writing of Minority Students

    Institute of Scientific and Technical Information of China (English)

    徐雪琴; 李少平

    2015-01-01

    The ultimate goal of Chinese as a second language teaching is to cultivate learners'actual language using ability.Writ-ten expression ability is one of the four language sKills.It is also the important content of language ability.Improving written sKills for Chinese learners whose mother tongue is Chinese is very important.Evaluation is a Key linK of the Chinese writing teaching,and the effectiveness of feedbacK in writing teaching evaluation plays a decisive role.So it is worthy of paying atten-tion to Chinese writing teaching from the perspective of evaluation in teaching Chinese as second language.The thesis bases on the Process teaching method and discusses ethnic minorities in Xinjiang from the empirical perspective for the teaching object of Chinese writing teaching evaluation of teacher's feedbacK on the impact of improving learners'writing,analyses the learner's need for feedbacK and existing problems.%汉语作为第二语言教学的最终目标是培养学习者的语言实际运用能力。书面表达能力是四项言语技能之一,也是语言能力的重要内容,那么提高书面表达能力对于汉语为非母语的汉语学习者十分重要。评价是汉语写作教学中的一个关键环节,而评价的反馈有效性在写作教学评价中起着决定性作用,因此从评价的反馈有效性的角度研究汉语写作教学是汉语作为第二语言教学中十分值得关注的论题。本文以过程教学法为基本的理论基础,从实证角度探讨了以新疆少数民族学生为教学对象的汉语写作教学评价中教师的反馈对提高学习者写作水平所产生的影响,分析了学习者对反馈的需要以及存在的问题。

  2. Hydrographic processing considerations in the “Big Data” age: An overview of technology trends in ocean and coastal surveys

    Science.gov (United States)

    Holland, M.; Hoggarth, A.; Nicholson, J.

    2016-04-01

    The quantity of information generated by survey sensors for ocean and coastal zone mapping has reached the “Big Data” age. This is influenced by the number of survey sensors available to conduct a survey, high data resolution, commercial availability, as well as an increased use of autonomous platforms. The number of users of sophisticated survey information is also growing with the increase in data volume. This is leading to a greater demand and broader use of the processed results, which includes marine archeology, disaster response, and many other applications. Data processing and exchange techniques are evolving to ensure this increased accuracy in acquired data meets the user demand, and leads to an improved understanding of the ocean environment. This includes the use of automated processing, models that maintain the best possible representation of varying resolution data to reduce duplication, as well as data plug-ins and interoperability standards. Through the adoption of interoperable standards, data can be exchanged between stakeholders and used many times in any GIS to support an even wider range of activities. The growing importance of Marine Spatial Data Infrastructure (MSDI) is also contributing to the increased access of marine information to support sustainable use of ocean and coastal environments. This paper offers an industry perspective on trends in hydrographic surveying and processing, and the increased use of marine spatial data.

  3. Augmenting Environmental Interaction in Audio Feedback Systems

    Directory of Open Access Journals (Sweden)

    Seunghun Kim

    2016-04-01

    Full Text Available Audio feedback is defined as a positive feedback of acoustic signals where an audio input and output form a loop, and may be utilized artistically. This article presents new context-based controls over audio feedback, leading to the generation of desired sonic behaviors by enriching the influence of existing acoustic information such as room response and ambient noise. This ecological approach to audio feedback emphasizes mutual sonic interaction between signal processing and the acoustic environment. Mappings from analyses of the received signal to signal-processing parameters are designed to emphasize this specificity as an aesthetic goal. Our feedback system presents four types of mappings: approximate analyses of room reverberation to tempo-scale characteristics, ambient noise to amplitude and two different approximations of resonances to timbre. These mappings are validated computationally and evaluated experimentally in different acoustic conditions.

  4. KEKB bunch feedback systems

    Energy Technology Data Exchange (ETDEWEB)

    Tobiyama, M.; Kikutani, E. [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

    1996-08-01

    Design and the present status of the bunch by bunch feedback systems for KEKB rings are shown. The detection of the bunch oscillation are made with the phase detection for longitudinal plane, the AM/PM method for transverse plane. Two GHz component of the bunch signal which is extracted with an analog FIR filter is used for the detection. Hardware two-tap FIR filter systems to shift the phase of the oscillation by 90deg will be used for the longitudinal signal processing. The same system will be used with no filtering but with only digital delay for transverse system. The candidate for the kicker and the required maximum power are also estimated. (author)

  5. Walk-through survey report: control technology for fermentation processes at Wyeth Laboratories, Inc. , West Chester, Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, K.F.

    1985-10-01

    A walk-through survey was conducted at Wyeth Laboratories, Incorporated, West Chester, Pennsylvania in November, 1983. The purpose of the survey was to evaluate the control technology for the fermentation processes. The facility produced penicillin-V and penicillin-G using the microbial strain Penicillium-chrysogenum. Medical examinations were available for fermentation and extraction process workers. Safety shoes and glasses and disposable dust respirators were provided. The author concludes that Wyeth has in operation an apparently effective system of control measures.

  6. TOPICAL REVIEW: A survey of signal processing algorithms in brain computer interfaces based on electrical brain signals

    Science.gov (United States)

    Bashashati, Ali; Fatourechi, Mehrdad; Ward, Rabab K.; Birch, Gary E.

    2007-06-01

    Brain computer interfaces (BCIs) aim at providing a non-muscular channel for sending commands to the external world using the electroencephalographic activity or other electrophysiological measures of the brain function. An essential factor in the successful operation of BCI systems is the methods used to process the brain signals. In the BCI literature, however, there is no comprehensive review of the signal processing techniques used. This work presents the first such comprehensive survey of all BCI designs using electrical signal recordings published prior to January 2006. Detailed results from this survey are presented and discussed. The following key research questions are addressed: (1) what are the key signal processing components of a BCI, (2) what signal processing algorithms have been used in BCIs and (3) which signal processing techniques have received more attention?

  7. Survey the Process of Collection and Turnover of Receivables, Yearly Budget Laws in Health Sector

    Directory of Open Access Journals (Sweden)

    Ahmad Rahbar

    2016-09-01

    Full Text Available Background & Aims of the Study:  The evaluation of financial performance is one of the main tasks of the manager that is very important. Any decision-making and rational planning in order to increase the productivity and survey the effect of adopted decision on the organization performance is in relation to the accurate assessment of financial performance. The aim of this study was to investigate the process of collection and turnover of receivables and rules of hospital budget in Qom University of medical sciences during the fourth and fifth development plans. Materials and Methods: This is a descriptive-analytic and cross-sectional study. It was used from researcher-made forms for collecting data. The data after collection from financial filing unit entered to the excel software and then the period of receivables collection, circulation of receivables,average daily sales and average intake accounts were analyzed,using activity ratios formula. Results: Our findings show that during the fourth and fifth development programs, the turnover of receivables decreased from four times to three times in the year and it is less than the least standard that is five times in the year. The period of receivables collection increased from 72 days to 147 days and it is more than the maximum standard that is 67 days. This issue is the indication of bad situations of insurance companies of under-contract with hospitals in paying of their obligations during study period. Conclusion: The period of collection and turnover of receivables of selected hospitals takes distance from the standard amount that needs to intervention at the macro level of decision-making. This study showed that resorting to legal leverage over the fourth and fifth development plan have not any impact on the improvement of reimbursement process. Therefore, the practical action of politicians about reformation of insurance’s structure and review of the ways of financing can be effective.

  8. Final report, Feedback limitations of photosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Sharkey, Thomas D.

    1999-07-22

    Final report of research on carbon metabolism of photosynthesis. The feedback from carbon metabolism to primary photosynthetic processes is summarized, and a comprehensive list of published scientific papers is provided.

  9. Feedback: an essential element of student learning in clinical practice.

    Science.gov (United States)

    Clynes, Mary P; Raftery, Sara E C

    2008-11-01

    Clinical practice is an essential component of the nursing curriculum. In order for the student to benefit fully from the experience regular performance feedback is required. Feedback should provide the student with information on current practice and offer practical advice for improved performance. The importance of feedback is widely acknowledged however it appears that there is inconsistency in its provision to students. The benefits of feedback include increased student confidence, motivation and self-esteem as well as improved clinical practice. Benefits such as enhanced interpersonal skills and a sense of personal satisfaction also accrue to the supervisor. Barriers to the feedback process are identified as inadequate supervisor training and education, unfavourable ward learning environment and insufficient time spent with students. In addition to the appropriate preparation of the supervisor effective feedback includes an appreciation of the steps of the feedback process, an understanding of the student response to feedback and effective communication skills.

  10. Negative feedback effects on star formation history and cosmic reionization

    CERN Document Server

    Wang, Lei; Xiang, Shouping; Yuan, Ye-Fei

    2008-01-01

    After considering the effects of negative feedback on the process of star formation, we explore the relationship between star formation process and the associated feedback, by investigating how the mechanical feedback from supernovae(SNe) and radiative feedback from luminous objects regulate the star formation rate and therefore affect the cosmic reionization.Based on our present knowledge of the negative feedback theory and some numerical simulations, we construct an analytic model in the framework of the Lambda cold dark matter model. In certain parameter regions, our model can explain some observational results properly. In large halos(T_vir>10000 K), both mechanical and radiative feedback have a similar behavior: the relative strength of negative feedback reduces as the redshift decreases. In contrast, in small halos (T_vir<10000 K$) that are thought to breed the first stars at early time, the radiative feedback gets stronger when the redshift decreases. And the star formation rate in these small halos...

  11. Paper Review Revolution: Screencasting Feedback for Developmental Writers

    Science.gov (United States)

    Boone, Joni; Carlson, Susan

    2011-01-01

    Researchers from Kaplan University present findings from a media-rich feedback pilot program that targets students from developmental writing courses. One study of student reactions reveals how screencasting feedback encouraged more formative, holistic feedback and students' awareness of writing process, audience, and revision. A second study…

  12. RF feedback for KEKB

    Energy Technology Data Exchange (ETDEWEB)

    Ezura, Eizi; Yoshimoto, Shin-ichi; Akai, Kazunori [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

    1996-08-01

    This paper describes the present status of the RF feedback development for the KEK B-Factory (KEKB). A preliminary experiment concerning the RF feedback using a parallel comb-filter was performed through a choke-mode cavity and a klystron. The RF feedback has been tested using the beam of the TRISTAN Main Ring, and has proved to be effective in damping the beam instability. (author)

  13. Neural cryptography with feedback

    Science.gov (United States)

    Ruttor, Andreas; Kinzel, Wolfgang; Shacham, Lanir; Kanter, Ido

    2004-04-01

    Neural cryptography is based on a competition between attractive and repulsive stochastic forces. A feedback mechanism is added to neural cryptography which increases the repulsive forces. Using numerical simulations and an analytic approach, the probability of a successful attack is calculated for different model parameters. Scaling laws are derived which show that feedback improves the security of the system. In addition, a network with feedback generates a pseudorandom bit sequence which can be used to encrypt and decrypt a secret message.

  14. Neural cryptography with feedback.

    Science.gov (United States)

    Ruttor, Andreas; Kinzel, Wolfgang; Shacham, Lanir; Kanter, Ido

    2004-04-01

    Neural cryptography is based on a competition between attractive and repulsive stochastic forces. A feedback mechanism is added to neural cryptography which increases the repulsive forces. Using numerical simulations and an analytic approach, the probability of a successful attack is calculated for different model parameters. Scaling laws are derived which show that feedback improves the security of the system. In addition, a network with feedback generates a pseudorandom bit sequence which can be used to encrypt and decrypt a secret message.

  15. Disparities in Feedback Provision to Emergency Medical Services Professionals.

    Science.gov (United States)

    Cash, Rebecca E; Crowe, Remle P; Rodriguez, Severo A; Panchal, Ashish R

    2017-06-16

    Feedback to EMS professionals is a critical component for optimizing patient care and outcomes in the prehospital setting. There is a paucity of data concerning the feedback received by prehospital providers. The objective of this study was to describe the prevalence of feedback received by EMS professionals in the past 30 days including the types, sources, modes, and utility of feedback. The secondary objective was to identify factors associated with receiving any feedback and, specifically, feedback regarding medical care provided. This was a cross-sectional survey examining currently practicing nationally certified EMS patient care providers (EMT or higher) in non-military and non-tribal settings. Data were collected on provider characteristics along with feedback received. Descriptive statistics were calculated, and multivariable logistic regression models were constructed to assess the relationship between EMS provider characteristics and receiving feedback. A non-respondent survey was administered to assess for non-response bias. Responses from 32,314 EMS providers were received (response rate = 10.4%) with 15,766 meeting inclusion criteria. In the 30 days preceding the survey, 69.4% (n = 10,924) of respondents received at least one type of feedback with 54.7% (n = 8,592) reporting receiving medical care feedback. Multivariable logistic regression modeling indicated that higher certification level, fewer years of experience in EMS, working for a hospital-based agency, air medical service, and higher weekly call volumes were significantly associated with increased odds of having received at least one type of feedback, and specifically medical care feedback. Additionally, providing primarily medical/convalescent transport and more years of EMS experience were significantly associated with decreased odds of receiving feedback. Feedback to EMS providers is critical to improving prehospital care. In this study, nearly a third of providers did not receive any

  16. Developing 360 degree feedback system for KINS

    Energy Technology Data Exchange (ETDEWEB)

    Han, In Soo; Cheon, B. M.; Kim, T. H.; Ryu, J. H. [Chungman National Univ., Daejeon (Korea, Republic of)

    2003-12-15

    This project aims to investigate the feasibility of a 360 degree feedback systems for KINS and to design guiding rules and structures in implementing that systems. Literature survey, environmental analysis and questionnaire survey were made to ensure that 360 degree feedback is the right tool to improve performance in KINS. That review leads to conclusion that more readiness and careful feasibility review are needed before implementation of 360 degree feedback in KINS. Further the project suggests some guiding rules that can be helpful for successful implementation of that system in KINS. Those include : start with development, experiment with one department, tie it to a clear organization's goal, train everyone involve, make sure to try that system in an atmosphere of trust.

  17. Policy Feedback System (PFS)

    Data.gov (United States)

    Social Security Administration — The Policy Feedback System (PFS) is a web application developed by the Office of Disability Policy Management Information (ODPMI) team that gathers empirical data...

  18. From patient surveys to organizational change

    DEFF Research Database (Denmark)

    Nielsen, Jørn Flohr; Riiskjær, Erik

    2013-01-01

    the information to change procedures and increase patient satisfaction. Thus, the article analyses the local adoption of semi-customized patient surveys and actor responses to survey results. Patient survey data from 100 Danish wards are related to ex post comments from department heads/hospital managers......From a rational perspective, patient surveys should be tools for purposeful planned change. They are feedback on performance and provide input to problem-solving processes. However, in public health care there are well-documented institutional forces, including doctors’ and nurses’ norms, which...... might complicate a rational change process. To understand the dynamics, a rational perspective must include the institutional context. From this perspective, the aim of this article is to compare the use of patient surveys in different hospital units in order to understand why some units are able to use...

  19. Training practices of cell processing laboratory staff : Analysis of a survey by the Alliance for Harmonization of Cellular Therapy Accreditation

    NARCIS (Netherlands)

    Keever-Taylor, Carolyn A.; Slaper-Cortenbach, Ineke; Celluzzi, Christina; Loper, Kathy; Aljurf, Mahmoud; Schwartz, Joseph; Mcgrath, Eoin; Eldridge, Paul

    2015-01-01

    Background aims: Methods for processing products used for hematopoietic progenitor cell (HPC) transplantation must ensure their safety and efficacy. Personnel training and ongoing competency assessment is critical to this goal. Here we present results from a global survey of methods used by a

  20. Feedback is good or bad? Medical residents’ points of view on feedback in clinical education

    Directory of Open Access Journals (Sweden)

    LEILA BAZRAFKAN

    2013-04-01

    Full Text Available Introduction: Feedback is very important in education and can help quality in the training process and orient the trainees in clinical contexts. This study aimed to assess the residents’ points of view about feedback in clinical education at Shiraz University of Medical Sciences. Methods: The sample of this study included 170 medical residents attending medical workshops in Shiraz University of Medical Sciences. The residents filled a valid and reliable questionnaire containing 21 items on their perceptions of the feedback they got throughout the workshops. The data were analyzed using SPSS version 14. Results: The study revealed that residents, generally, have a positive perception of feedback in their training. The highest score belonged to the items such as “feedback was applicable to future work”, “feedback corrected my behavior”, “feedback worked as a motivation for education” and “feedback was specific in one subject”. Residents who had a negative feedback experience also increased their efforts to learn. The Surgery residents acquired the highest scores while radiology residents got the lowest. The difference between these groups was statistically significant (P = 0.000. Conclusion: The highest mean score belonged to internal medicine residents. This shows that residents believe that obstetrics & gynecology ward is a ward in which the formative assessment is much more powerful in comparison to the other three major wards. The surgery ward received the lowest score for formative assessment and this shows that the feedback in surgery ward is very low.

  1. Sentiment analysis on students’ real-time feedback

    OpenAIRE

    Altrabsheh, Nabeela

    2016-01-01

    Previous literature identifies that students’ real-time feedback is important in the learning process. There are numerous studies that have collected students’ feedback in real time. However, they include several limitations of which the most important is analysing the feedback. In this thesis, we address these limitations by proposing a system that will automatically analyse students’ feedback in real time and present the analysis results to the lecturer. To create such a system, we propose ...

  2. Feedback Loop Gains and Feedback Behavior (1996)

    DEFF Research Database (Denmark)

    Kampmann, Christian Erik

    2012-01-01

    Linking feedback loops and system behavior is part of the foundation of system dynamics, yet the lack of formal tools has so far prevented a systematic application of the concept, except for very simple systems. Having such tools at their disposal would be a great help to analysts in understanding...... large, complicated simulation models. The paper applies tools from graph theory formally linking individual feedback loop strengths to the system eigenvalues. The significance of a link or a loop gain and an eigenvalue can be expressed in the eigenvalue elasticity, i.e., the relative change...... of an eigenvalue resulting from a relative change in the gain. The elasticities of individual links and loops may be found through simple matrix operations on the linearized system. Even though the number of feedback loops can grow rapidly with system size, reaching astronomical proportions even for modest systems...

  3. Written Corrective Feedback in Second Language Acquisition and Writing

    Science.gov (United States)

    Bitchener, John; Ferris, Dana R.

    2011-01-01

    What should language and writing teachers do about giving students written corrective feedback? This book surveys theory, research, and practice on the important and sometimes controversial issue of written corrective feedback, also known as "error/grammar correction," and its impact on second language acquisition and second language writing…

  4. Written Corrective Feedback in Second Language Acquisition and Writing

    Science.gov (United States)

    Bitchener, John; Ferris, Dana R.

    2011-01-01

    What should language and writing teachers do about giving students written corrective feedback? This book surveys theory, research, and practice on the important and sometimes controversial issue of written corrective feedback, also known as "error/grammar correction," and its impact on second language acquisition and second language writing…

  5. Global desertification: Drivers and feedbacks

    Science.gov (United States)

    D'Odorico, Paolo; Bhattachan, Abinash; Davis, Kyle F.; Ravi, Sujith; Runyan, Christiane W.

    2013-01-01

    Desertification is a change in soil properties, vegetation or climate, which results in a persistent loss of ecosystem services that are fundamental to sustaining life. Desertification affects large dryland areas around the world and is a major cause of stress in human societies. Here we review recent research on the drivers, feedbacks, and impacts of desertification. A multidisciplinary approach to understanding the drivers and feedbacks of global desertification is motivated by our increasing need to improve global food production and to sustainably manage ecosystems in the context of climate change. Classic desertification theories look at this process as a transition between stable states in bistable ecosystem dynamics. Climate change (i.e., aridification) and land use dynamics are the major drivers of an ecosystem shift to a “desertified” (or “degraded”) state. This shift is typically sustained by positive feedbacks, which stabilize the system in the new state. Desertification feedbacks may involve land degradation processes (e.g., nutrient loss or salinization), changes in rainfall regime resulting from land-atmosphere interactions (e.g., precipitation recycling, dust emissions), or changes in plant community composition (e.g., shrub encroachment, decrease in vegetation cover). We analyze each of these feedback mechanisms and discuss their possible enhancement by interactions with socio-economic drivers. Large scale effects of desertification include the emigration of “environmental refugees” displaced from degraded areas, climatic changes, and the alteration of global biogeochemical cycles resulting from the emission and long-range transport of fine mineral dust. Recent research has identified some possible early warning signs of desertification, which can be used as indicators of resilience loss and imminent shift to desert-like conditions. We conclude with a brief discussion on some desertification control strategies implemented in different

  6. ASD Customer Satisfaction Survey

    Data.gov (United States)

    Department of Veterans Affairs — ASD implemented a customer satisfaction survey for our products and services. This feedback will provide a better understanding of how ASD products and services can...

  7. Healthcare system intervention for prevention of birth injuries – process evaluation of self-assessment, peer review, feedback and agreement for change

    Directory of Open Access Journals (Sweden)

    Nyström Monica E

    2012-08-01

    Full Text Available Abstract Background Patient safety is fundamental in high quality healthcare systems but despite an excellent record of perinatal care in Sweden some children still suffer from substandard care and unnecessary birth injuries. Sustainable patient safety improvements assume changes in key actors’ mental models, norms and culture as well as in the tools, design and organisation of work. Interventions positively affecting team mental models on safety issues are a first step to enhancing change. Our purpose was to study a national intervention programme for the prevention of birth injuries with the aim to elucidate how the main interventions of self-assessment, peer review, feedback and written agreement for change affected the teams and their mental model of patient safety, and thereby their readiness for change. Knowledge of relevant considerations before implementing this type of patient safety intervention series could thereby be increased. Methods Eighty participants in twenty-seven maternity units were interviewed after the first intervention sequence of the programme. A content analysis using a priori coding was performed in order to relate results to the anticipated outcomes of three basic interventions: self-assessment, peer review and written feedback, and agreement for change. Results The self-assessment procedure was valuable and served as a useful tool for elucidating strengths and weaknesses and identifying areas for improvement for a safer delivery in maternity units. The peer-review intervention was appreciated, despite it being of less value when considering the contribution to explicit outcome effects (i.e. new input to team mental models and new suggestions for actions. The feedback report and the mutual agreement on measures for improvements reached when signing the contract seemed exert positive pressures for change. Conclusions Our findings are in line with several studies stressing the importance of self-evaluation by

  8. Generations and Gender Survey (GGS: Towards a Better Understanding of Relationships and Processes in the Life Course

    Directory of Open Access Journals (Sweden)

    Zsolt Spéder

    2007-11-01

    Full Text Available The Generations and Gender Survey (GGS is one of the two pillars of the Generations and Gender Programme designed to improve understanding of demographic and social development and of the factors that influence these developments. This article describes how the theoretical perspectives applied in the survey, the survey design and the questionnaire are related to this objective. The key features of the survey include panel design, multidisciplinarity, comparability, context-sensitivity, inter-generational and gender relationships. The survey applies the life course approach, focussing on the processes of childbearing, partnership dynamics, home leaving, and retiring. The selection of topics for data collection mainly follows the criterion of theoretically grounded relevance to explaining one or more of the mentioned processes. A large portion of the survey deals with economic aspects of life, such as economic activity, income, and economic well-being; a comparably large section is devoted to values and attitudes. Other domains covered by the survey include gender relationships, household composition and housing, residential mobility, social networks and private transfers, education, health, and public transfers. The third chapter of the article describes the motivations for their inclusion. The GGS questionnaire is designed for a face-to-face interview. It includes the core that each participating country needs to implement in full, and four optional sub-modules on nationality and ethnicity, on previous partners, on intentions of breaking up, and on housing, respectively. The participating countries are encouraged to include also the optional sub-modules to facilitate comparative research on these topics.

  9. Microbiology of processed edible insect products - Results of a preliminary survey.

    Science.gov (United States)

    Grabowski, Nils Th; Klein, Günter

    2017-02-21

    Little is known of the microbiology of processed insect products. The present survey analysed a total of n=38 samples of deep-fried and spiced (Acheta domesticus, Locusta migratoria, and Omphisa fuscidentalis), cooked in soy sauce ("tsukudani"; Oxya yezoensis, Vespula flaviceps, and Bombyx mori), dried (A. domesticus, L. migatoria, Alphitobius diaperinus, Tenebrio molitor, B. mori, Hermetia illucens, and Musca domestica), powdered (H. illucens, T. molitor) and other (incl. deep-frozen B. mori and honeybee pollen) insect products microbiologically (total bacterial count [TBC], Enterobacteriaceae, staphylococci, bacilli, and yeasts and moulds counts, salmonellae, Listeria monocytogenes, and Escherichia coli). Although each product type revealed a microbiological profile of its own, dried and powdered insects ("class I") displayed markedly higher counts than the deep-fried and cooked ones ("class II"). Thresholds between class I and II products were estimated at 4.0 (TBC), 1.0 (Enterobacteriaceae, yeasts and moulds), 2.5 (staphylococci), and 3.0lgcfu/g (bacilli). All samples were negative for salmonellae, L. monocytogenes, E. coli and Stapyhlococcus aureus, but dried and powdered insects, as well as pollen, contained B. cereus, coliforms, Serratia liquefaciens, Listeria ivanovii, Mucor spp., Aspergillus spp., Penicillium spp., and Cryptococcus neoformans. Comparing the results with the hygiene criteria for edible insects proposed by Belgium and the Netherlands, class I products failed to comply with many bacterial count limits despite the absence of classical food pathogens. Therefore, class I products should always be consumed after another heating step as indicated by the manufacturer, until drying techniques are able to ensure lower bacterial counts. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. An adaptive phase alignment algorithm for cartesian feedback loops

    Science.gov (United States)

    Gimeno-Martin, A.; Pardo-Martin, J.; Ortega-Gonzalez, F.

    2010-01-01

    An adaptive algorithm to correct phase misalignments in Cartesian feedback linearization loops for power amplifiers has been presented. It yields an error smaller than 0.035 rad between forward and feedback loop signals once convergence is reached. Because this algorithm enables a feedback system to process forward and feedback samples belonging to almost the same algorithm iteration, it is suitable to improve the performance not only of power amplifiers but also any other digital feedback system for communications systems and circuits such as all digital phase locked loops. Synchronizing forward and feedback paths of Cartesian feedback loops takes a small period of time after the system starts up. The phase alignment algorithm needs to converge before the feedback Cartesian loop can start its ideal behavior. However, once the steady state is reached, both paths can be considered synchronized, and the Cartesian feedback loop will only depend on the loop parameters (open-loop gain, loop bandwidth, etc.). It means that the linearization process will also depend only on these parameters since the misalignment effect disappears. Therefore, this algorithm relieves the power amplifier linearizer circuit design of any task required for solving phase misalignment effects inherent to Cartesian feedback systems. Furthermore, when a feedback Cartesian loop has to be designed, the designer can consider that forward and feedback paths are synchronized, since the phase alignment algorithm will do this task. This will reduce the simulation complexity. Then, all efforts are applied to determining the suitable loop parameters that will make the linearization process more efficient.

  11. Feedback and assessment for clinical placements: achieving the right balance

    Directory of Open Access Journals (Sweden)

    Burgess A

    2015-05-01

    Full Text Available Annette Burgess, Craig Mellis Central Clinical School, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia Abstract: During clinical placements, the provision of feedback forms an integral part of the learning process and enriches students' learning experiences. The purpose of feedback is to improve the learner's knowledge, skills, or behavior. Receipt of accurate feedback can help to narrow the gap between actual and desired performance. Effective and regular feedback has the potential to reinforce good practice and motivate the learner toward the desired outcome. Despite the obvious role of feedback in effective teaching and learning, a common complaint from students is that they do not receive adequate feedback. Unfortunately, skills in giving and receiving feedback are rarely taught to students or clinicians. This study aims to provide an understanding of the role of feedback within the learning process, consider consequences of inadequate or poorly given feedback, consider the barriers to the feedback process, provide practical guidelines for providing feedback, and consider the need for student and faculty development in feedback skills. Keywords: medical students, formative, summative, assessment

  12. A two-part process for assessing the adequacy of hydrographic surveys and nautical chart coverage

    Science.gov (United States)

    Azuike, Chukwuma

    IHO Publication C-55 contains information about the progress of hydrographic surveying and nautical charting for littoral states. Listed primarily as percent coverage, it is difficult to use this information to determine: 1) if the current level of surveying or charting is adequate or in need of action, or 2) can be used to compare different locations. An analysis methodology has been developed to assess the adequacy of hydrographic surveying and nautical charting coverage. Indications of chart adequacy as depicted on charts or sailing directions are spatially correlated with significant maritime areas associated with navigational/national interest. However, an analysis based solely on these datasets is limited without access to the current depth information. Publically-available, multi-spectral satellite imagery can be used to derive estimates of bathymetry and provide information in previously unsurveyed areas. Preliminary results show that multi-spectral satellite remote sensing is potentially beneficial as a reconnaissance tool prior to a hydrographic survey.

  13. Individual Differences in the Encoding Processes of Egocentric and Allocentric Survey Knowledge

    National Research Council Canada - National Science Library

    Wen, Wen; Ishikawa, Toru; Sato, Takao

    2013-01-01

    This study examined how different components of working memory are involved in the acquisition of egocentric and allocentric survey knowledge by people with a good and poor sense of direction (SOD). We employed a dual...

  14. Feedback og interpersonel kommunikation

    DEFF Research Database (Denmark)

    Dindler, Camilla

    2016-01-01

    Som interpersonel kommunikationsform handler feedback om at observere, mærke og italesætte det, som handler om relationen mellem samtaleparterne mere end om samtaleemnet. Her er fokus på, hvad der siges og hvordan der kommunikeres sammen. Feedback er her ikke en korrigerende tilbagemelding til...

  15. "Feedback" For Instructioal Television.

    Science.gov (United States)

    Schramm, Wilbur

    A number of different methods have been used by instructional television (ITV) projects to obtain audience feedback, and some of these are now being used in the ITV system in El Salvador. We know that pretesting programs on a representative sample can bring considerable gains in learning. Another feedback source can be a classroom of pupils in the…

  16. Going Full Circle With Teacher Feedback

    Directory of Open Access Journals (Sweden)

    Jo-Anne L. Manswell Butty

    2015-07-01

    Full Text Available Research on the evaluation of early childhood programs focuses mainly on its outcomes rather than its process with often little attention given to the role that feedback to teachers in pre-kindergarten (pre-k programs plays in the larger cycle of the evaluation process. This article provides a case example of a multiyear evaluation of community-based pre-k programs serving about 360 three- and four-year old children over a 5-year period in the District of Columbia. The Closing the Loop Evaluation Model proposed represents a responsive evaluation approach that illustrates the interconnected interactions between teacher feedback during the evaluation process and two supporting evaluation methodologies that emphasize social justice and utility. Findings from the case example highlight the responsive evaluation approach, feedback process, and ensuing conceptual and instrumental changes that occurred among stakeholders from whole-group feedback to small-group “report card” meetings with add-ons such as technical assistance, teacher-generated action plans, and teacher follow-up and feedback to close the evaluation loop. The authors discuss lessons learned about the evaluation process from the case example around aspects of feedback, including timing, audience, and function. Findings highlight the importance of feedback being timely and prompt, high quality in focus and content, non-punitive, collaborative, concise, and useful. The authors conclude that an evaluation process that includes teacher feedback, couched in social justice and utility, can have positive outcomes for all stakeholders and will likely lead to higher quality early childhood education programs.

  17. Feedback i matematik

    DEFF Research Database (Denmark)

    Sortkær, Bent

    2017-01-01

    Feedback bliver i litteraturen igen og igen fremhævet som et af de mest effektive midler til at fremme elevers præstationer i skolen (Hartberg, Dobson, & Gran, 2012; Hattie & Timperley, 2007; Wiliam, 2015). Dette på trods af, at flere forskere påpeger, at feedback ikke altid er læringsfremmende...... (Hattie & Gan, 2011), og nogle endda viser, at feedback kan have en negativ virkning i forhold til præstationer (Kluger & DeNisi, 1996). Artiklen vil undersøge disse tilsyneladende modstridende resultater ved at stille spørgsmålet: Under hvilke forudsætninger virker feedback i matematik læringsfremmende......? Dette gøres ved at dykke ned i forskningslitteraturen omhandlende feedback ud fra en række temaer for på den måde at besvare ovenstående spørgsmål....

  18. Feedback and Incentives:

    DEFF Research Database (Denmark)

    Eriksson, Tor Viking; Poulsen, Anders; Villeval, Marie-Claire

    This paper experimentally investigates the impact of different pay and relative performance information policies on employee effort. We explore three information policies: No feedback about relative performance, feedback given halfway through the production period, and continuously updated feedback....... The pay schemes are a piece rate payment scheme and a winner-takes-all tournament. We find that, regardless of the pay scheme used, feedback does not improve performance. There are no significant peer effects in the piece-rate pay scheme. In contrast, in the tournament scheme we find some evidence...... of positive peer effects since the underdogs almost never quit the competition even when lagging significantly behind, and frontrunners do not slack off. Moreover, in both pay schemes information feedback reduces the quality of the low performers' work....

  19. Situated Formative Feedback

    DEFF Research Database (Denmark)

    Lukassen, Niels Bech; Wahl, Christian; Sorensen, Elsebeth Korsgaard

    2016-01-01

    feedback episode (FFE) through an online dialogue. The paper argues that dialogue is crucial for student learning and that feedback is not only something the teacher gives to the student. Viewing good quality feedback as social, situated, formative, emphasis is put on the establishment of dialogue. We...... refer to this type of feedback as, Situated Formative Feedback (SFF). As a basis for exploring, identifying and discussing relevant aspects of SFF the paper analyses qualitative data from a Moodle dialogue. Data are embedded in the qualitative analytic program Nvivo and are analysed with a system...... theoretical textual analysis method. Asynchronous written dialogue from an online master’s course at Aalborg University forms the empirical basis of the study. The findings suggests in general that students play an essential role in SFF and that students and educators are equal in the COP, but holds different...

  20. The VIRUS-P Exploration of Nearby Galaxies (VENGA): Survey Design, Data Processing, and Spectral Analysis Methods

    Science.gov (United States)

    Blanc, Guillermo A.; Weinzirl, Tim; Song, Mimi; Heiderman, Amanda; Gebhardt, Karl; Jogee, Shardha; Evans, Neal J., II; van den Bosch, Remco C. E.; Luo, Rongxin; Drory, Niv; Fabricius, Maximilian; Fisher, David; Hao, Lei; Kaplan, Kyle; Marinova, Irina; Vutisalchavakul, Nalin; Yoachim, Peter

    2013-05-01

    We present the survey design, data reduction, and spectral fitting pipeline for the VIRUS-P Exploration of Nearby Galaxies (VENGA). VENGA is an integral field spectroscopic survey, which maps the disks of 30 nearby spiral galaxies. Targets span a wide range in Hubble type, star formation activity, morphology, and inclination. The VENGA data cubes have 5.''6 FWHM spatial resolution, ~5 Å FWHM spectral resolution, sample the 3600 Å-6800 Å range, and cover large areas typically sampling galaxies out to ~0.7R 25. These data cubes can be used to produce two-dimensional maps of the star formation rate, dust extinction, electron density, stellar population parameters, the kinematics and chemical abundances of both stars and ionized gas, and other physical quantities derived from the fitting of the stellar spectrum and the measurement of nebular emission lines. To exemplify our methods and the quality of the data, we present the VENGA data cube on the face-on Sc galaxy NGC 628 (a.k.a. M 74). The VENGA observations of NGC 628 are described, as well as the construction of the data cube, our spectral fitting method, and the fitting of the stellar and ionized gas velocity fields. We also propose a new method to measure the inclination of nearly face-on systems based on the matching of the stellar and gas rotation curves using asymmetric drift corrections. VENGA will measure relevant physical parameters across different environments within these galaxies, allowing a series of studies on star formation, structure assembly, stellar populations, chemical evolution, galactic feedback, nuclear activity, and the properties of the interstellar medium in massive disk galaxies.

  1. Feedback valence affects auditory perceptual learning independently of feedback probability

    OpenAIRE

    Amitay, S.; Moore, D. R.; Molloy, K.; Halliday, L. F.

    2015-01-01

    Previous studies have suggested that negative feedback is more effective in driving learning than positive feedback. We investigated the effect on learning of providing varying amounts of negative and positive feedback while listeners attempted to discriminate between three identical tones; an impossible task that nevertheless produces robust learning. Four feedback conditions were compared during training: 90% positive feedback or 10% negative feedback informed the participants that they wer...

  2. Delayed, but not immediate, feedback after multiple-choice questions increases performance on a subsequent short-answer, but not multiple-choice, exam: evidence for the dual-process theory of memory.

    Science.gov (United States)

    Sinha, Neha; Glass, Arnold Lewis

    2015-01-01

    Three experiments, two performed in the laboratory and one embedded in a college psychology lecture course, investigated the effects of immediate versus delayed feedback following a multiple-choice exam on subsequent short answer and multiple-choice exams. Performance on the subsequent multiple-choice exam was not affected by the timing of the feedback on the prior exam; however, performance on the subsequent short answer exam was better following delayed than following immediate feedback. This was true regardless of the order in which immediate versus delayed feedback was given. Furthermore, delayed feedback only had a greater effect than immediate feedback on subsequent short answer performance following correct, confident responses on the prior exam. These results indicate that delayed feedback cues a student's prior response and increases subsequent recollection of that response. The practical implication is that delayed feedback is better than immediate feedback during academic testing.

  3. Feedback som tredjeordensiagttagelse

    Directory of Open Access Journals (Sweden)

    Ane Qvortrup

    2013-09-01

    Full Text Available Feedback tilskrives stor betydning for læring, men trods intensiv forskning på området synes det svært at fange, hvori feedbacks særlige potentiale består. I forsøgene på at gøre dette knyttes an til en række faktorer eller parametre, der fremhæves som centrale. En af disse faktorer er tid, hvor der kredses om forskellen mellem umiddelbar og forsinket feedback samt om fordele og ulemper ved hver af de to. I denne artikel knyttes der an til en forståelse af feedback som tredjeordensiagttagelse, og der sættes herfra fokus på, hvordan man i en praktisk undervisningssituation kan imødekomme tidsfaktoren knyttet til feedback. Med udgangspunkt i et undervisningsforløb på bachelorniveau, hvor der er arbejdet systematisk med feedback understøttet af Wikis, belyses det, hvordan et sådant arbejde synes at have potentiale for understøttelse af såvel læring som undervisning. En sådan teoretisk reflekteret belysning kan udgøre et refleksionsprogram for fremtidig planlægning af og løbende refleksion over undervisning.     The article investigates the effect of feedback on learning. Feedback has been shown to be one of the most powerful influences on achievement in education. But, in spite of much research on the matter, there is no agreement on how the special potential of feedback can be described, and consequently no agreement on what is good and bad feedback. This article sets out to rectify this omission by seeking a new theoretical framework that is sensitive to the complexity of the impact of feedback. The author propose a system theoretical frame and through its use identifies significant didactical issues. Although feedback is described as an internal, system-relative construction, when seen through a system theoretical lens different teaching environments create diverse conditions for feedback constructions. The final section of the paper explores this idea in relation to wikis.

  4. Feedback som tredjeordensiagttagelse

    Directory of Open Access Journals (Sweden)

    Ane Qvortrup

    2013-09-01

    Full Text Available Feedback tilskrives stor betydning for læring, men trods intensiv forskning på området synes det svært at fange, hvori feedbacks særlige potentiale består. I forsøgene på at gøre dette knyttes an til en række faktorer eller parametre, der fremhæves som centrale. En af disse faktorer er tid, hvor der kredses om forskellen mellem umiddelbar og forsinket feedback samt om fordele og ulemper ved hver af de to. I denne artikel knyttes der an til en forståelse af feedback som tredjeordensiagttagelse, og der sættes herfra fokus på, hvordan man i en praktisk undervisningssituation kan imødekomme tidsfaktoren knyttet til feedback. Med udgangspunkt i et undervisningsforløb på bachelorniveau, hvor der er arbejdet systematisk med feedback understøttet af Wikis, belyses det, hvordan et sådant arbejde synes at have potentiale for understøttelse af såvel læring som undervisning. En sådan teoretisk reflekteret belysning kan udgøre et refleksionsprogram for fremtidig planlægning af og løbende refleksion over undervisning.  The article investigates the effect of feedback on learning. Feedback has been shown to be one of the most powerful influences on achievement in education. But, in spite of much research on the matter, there is no agreement on how the special potential of feedback can be described, and consequently no agreement on what is good and bad feedback. This article sets out to rectify this omission by seeking a new theoretical framework that is sensitive to the complexity of the impact of feedback. The author propose a system theoretical frame and through its use identifies significant didactical issues. Although feedback is described as an internal, system-relative construction, when seen through a system theoretical lens different teaching environments create diverse conditions for feedback constructions. The final section of the paper explores this idea in relation to wikis.

  5. Feedback Requirements for SASE-FELs

    Energy Technology Data Exchange (ETDEWEB)

    Loos, Henrik; /SLAC

    2012-07-06

    The operation of a Self Amplified Spontaneous Emission (SASE) Free Electron Lasers (FEL) at soft and hard X-ray wavelengths driven by a high brightness electron beam imposes strong requirements on the stability of the accelerator and feedback systems are necessary to both guarantee saturation of the SASE process as well as a stable photon beam for user experiments. Diagnostics for the relevant transverse and longitudinal beam parameters are presented and various examples of feedback systems for bunches with low repetition rate as well as systems for intra bunch train feedbacks are discussed.

  6. Haptic seat for fuel economy feedback

    Science.gov (United States)

    Bobbitt, III, John Thomas

    2016-08-30

    A process of providing driver fuel economy feedback is disclosed in which vehicle sensors provide for haptic feedback on fuel usage. Such sensors may include one or more of a speed sensors, global position satellite units, vehicle pitch/roll angle sensors, suspension displacement sensors, longitudinal accelerometer sensors, throttle position in sensors, steering angle sensors, break pressure sensors, and lateral accelerometer sensors. Sensors used singlely or collectively can provide enhanced feedback as to various environmental conditions and operating conditions such that a more accurate assessment of fuel economy information can be provided to the driver.

  7. Ten tips for receiving feedback effectively in clinical practice.

    Science.gov (United States)

    Algiraigri, Ali H

    2014-01-01

    Despite being recognized as a fundamental part of the educational process and emphasized for several decades in medical education, the influence of the feedback process is still suboptimal. This may not be surprising, because the focus is primarily centered on only one half of the process - the teachers. The learners are the targets of the feedback process and improvement needs to be shifted. Learners need to be empowered with the skills needed to receive and utilize feedback and compensate for less than ideal feedback delivery due to the busy clinical environment. Based on the available feedback literature and clinical experience regarding feedback, the author developed 10 tips to empower learners with the necessary skills to seek, receive, and handle feedback effectively, regardless of how it is delivered. Although, most of the tips are directed at the individual clinical trainee, this model can be utilized by clinical educators involved in learner development and serve as a framework for educational workshops or curriculum. Ten practical tips are identified that specifically address the learner's role in the feedback process. These tips not only help the learner to ask, receive, and handle the feedback, but will also ease the process for the teachers. Collectively, these tips help to overcome most, if not all, of the barriers to feedback and bridge the gaps in busy clinical practices. Feedback is a crucial element in the educational process and it is shown that we are still behind in the optimal use of it; thus, learners need to be taught how to better receive and utilize feedback. The focus in medical education needs to balance the two sides of the feedback process. It is time now to invest on the learner's development of skills that can be utilized in a busy day-to-day clinical practice.

  8. The Greenhouse Effect and Climate Feedbacks

    Science.gov (United States)

    Covey, C.; Haberle, R. M.; McKay, C. P.; Titov, D. V.

    This chapter reviews the theory of the greenhouse effect and climate feedback. It also compares the theory with observations, using examples taken from all four known terrestrial worlds with substantial atmospheres: Venus, Earth, Mars, and Titan. The greenhouse effect traps infrared radiation in the atmosphere, thereby increasing surface temperature. It is one of many factors that affect a world's climate. (Others include solar luminosity and the atmospheric scattering and absorption of solar radiation.) A change in these factors — defined as climate forcing — may change the climate in a way that brings other processes — defined as feedbacks — into play. For example, when Earth's atmospheric carbon dioxide increases, warming the surface, the water vapor content of the atmosphere increases. This is a positive feedback on global warming because water vapor is itself a potent greenhouse gas. Many positive and negative feedback processes are significant in determining Earth's climate, and probably the climates of our terrestrial neighbors.

  9. Strategies for effective feedback.

    Science.gov (United States)

    Kritek, Patricia A

    2015-04-01

    Provision of regular feedback to trainees on clinical performance by supervising providers is increasingly recognized as an essential component of undergraduate and graduate health sciences education; however, many individuals have not been formally trained in this pedagogical skill. At the bedside or in the clinic, effective performance feedback can be accomplished by following four key steps. Begin by setting expectations that incorporate the trainee's personal goals and external objectives. Delineate how and when you will provide feedback to the learner. Next, directly observe the trainee's performance. This can be challenging while engaged on a busy clinical service, but a focus on discrete activities or interactions (e.g., family meeting, intravascular volume assessment using bedside ultrasound, or obtaining informed consent) is helpful. The third step is to plan and prioritize the feedback session. Feedback is most effective when given in a timely fashion and delivered in a safe environment. Limit the issues addressed because learners often disengage if confronted with too many deficiencies. Finally, when delivering feedback, begin by listening to the trainee's self-evaluation and then take a balanced approach. Describe in detail what the trainee does well and discuss opportunities for improvement with emphasis on specific, modifiable behaviors. The feedback loop is completed with a plan for follow-up reassessment. Through the use of these relatively simple practices, both the trainee and teacher can have a more productive learning experience.

  10. Nursing Students' Perceptions of Anecdotal Notes as Formative Feedback.

    Science.gov (United States)

    Quance, Margaret Ann

    2016-08-24

    Anecdotal notes are a method of providing formative feedback to nursing students following clinical experiences. The extant literature on anecdotal notes is written only from the educator perspective, focusing on rationale for and methods of production, rather than on evaluation of effectiveness. A retrospective descriptive study was carried out with a cohort of 283 third year baccalaureate nursing students to explore their perceptions of anecdotal notes as effective formative feedback. The majority of students valued verbal as well as anecdotal note feedback. They preferred to receive feedback before the next learning experience. Students found the quality of feedback varied by instructor. The anecdotal note process was found to meet identified formative feedback requirements as well as the nursing program's requirement for transparency of evaluation and due process. It is necessary to provide professional development to clinical nurse educators to assist them develop high quality formative feedback using anecdotal notes.

  11. Feedback og motivation

    DEFF Research Database (Denmark)

    Bjerresgaard, Helle

    2016-01-01

    Feedback til elever, som enten er gået midlertidigt i stå eller i værste tilfælde oplever sig selv magtesløse, skal hjælpe dem til at etablere en tro på, at de kan øve indflydelse på og være betydningsfulde for deres omgivelser. Feedback sættes ofte i forbindelse med ’læring’. I denne artikel...... påvirket af en målrettet, individuel feedback – eller manglen på samme....

  12. A Platform for Closing the Open Data Feedback Loop Based on Web2.0 Functionality

    Directory of Open Access Journals (Sweden)

    Charalampos Alexopoulos

    2014-11-01

    Full Text Available One essential element of open data ecosystems concerns their development through feedback loops, discussions and dynamic supplier and user interactions. These user-centric features communicate the users’ needs to the open data community as well to the public sector bodies responsible for data publication. Addressing these needs by the corresponding public sector bodies or even by utilising the power of the community as ENGAGE supports will actually accelerate innovation. However, these elements appear barely to be part of existing open data practices. We conducted a survey which showed that most professional open data users did not know at least one open data infrastructure that enabled five specific types of discussion and feedback mechanisms. The survey showed that much can still be done to improve feedback and discussion on open data infrastructures. In this paper we discuss an open data platform which has started to contribute to filling this gap and present a usage scenario explaining the sequence of the underlined functionality. The discussed ENGAGE open data infrastructure combines functionalities to close the feedback loop and to return information to public authorities for better open data use and publication as well as establishing communication channels between stakeholders. This may effectively lead to the stimulation and facilitation of value generation from open data, as such functionality position the user at the centre of the open data publication process.

  13. Advice and Feedback: Elements of Practice for Problem Solving.

    Science.gov (United States)

    Phye, Gary D.; Sanders, Cheryl E.

    1994-01-01

    The roles of advice and feedback in the facilitation of online processing during acquisition and subsequent impact on memory-based processing during a delayed problem-solving task were studied in 2 experiments with 123 college students. Results indicate that corrective feedback improves online processing during training. (SLD)

  14. Research of multimedia mouse feedback control system based on image processing%基于图像处理的多媒体鼠标反馈控制系统研究

    Institute of Scientific and Technical Information of China (English)

    恩德; 王宁宁; 银兵

    2011-01-01

    This paper presents a multimedia feedback control system of mouse - based image processing. The system , by using the programming ideas of Visual Basic and MATLAB programming together, through a series of methods such as the Image gray processing, filtering, edge detection, background subtraction, gets the relative coordinate of the spot center in the image. Then relative coordinate is transformed into actual coordinate of the mouse of the multimedia computer through the specific conversion rules. Finally the projection gets the new image with the information of E - pointer, which achieves the feedback wireleas operation of the laser pointer spot to the mouse.%设计了一种基于图像处理的多媒体鼠标反馈控制系统,采用Visual Basic与MATLAB 相结合编程思想,通过图像灰度处理、图像滤波、图像边缘检测、图像背景差法等一系列方法,从采集的图像中得到光点中心在图像中的相对坐标,通过转换规则变成多媒体电脑鼠标的实际坐标,最终投影附加有电子教鞭信息的新画面,实现激光笔光点对鼠标的反馈式无线操作.

  15. A Comparison between Quantity Surveying and Information Technology Students on Web Application in Learning Process

    Science.gov (United States)

    Keng, Tan Chin; Ching, Yeoh Kah

    2015-01-01

    The use of web applications has become a trend in many disciplines including education. In view of the influence of web application in education, this study examines web application technologies that could enhance undergraduates' learning experiences, with focus on Quantity Surveying (QS) and Information Technology (IT) undergraduates. The…

  16. Survey of Processing Methods for High Strength High Conductivity Wires for High Field Magnet Applications

    Energy Technology Data Exchange (ETDEWEB)

    Han, K.; Embury, J.D.

    1998-10-01

    This paper will deal with the basic concepts of attaining combination of high strength and high conductivity in pure materials, in-situ composites and macrocomposites. It will survey current attainments, and outline where some future developments may lie in developing wire products that are close to the theoretical strength of future magnet applications.

  17. Individual Differences in the Encoding Processes of Egocentric and Allocentric Survey Knowledge

    Science.gov (United States)

    Wen, Wen; Ishikawa, Toru; Sato, Takao

    2013-01-01

    This study examined how different components of working memory are involved in the acquisition of egocentric and allocentric survey knowledge by people with a good and poor sense of direction (SOD). We employed a dual-task method and asked participants to learn routes from videos with verbal, visual, and spatial interference tasks and without any…

  18. Star Cluster Formation and Feedback

    CERN Document Server

    Krumholz, Mark R; Arce, Hector G; Dale, James E; Gutermuth, Robert; Klein, Richard I; Li, Zhi-Yun; Nakamura, Fumitaka; Zhang, Qizhou

    2014-01-01

    Stars do not generally form in isolation. Instead, they form in clusters, and in these clustered environments newborn stars can have profound effects on one another and on their parent gas clouds. Feedback from clustered stars is almost certainly responsible for a number of otherwise puzzling facts about star formation: that it is an inefficient process that proceeds slowly when averaged over galactic scales; that most stars disperse from their birth sites and dissolve into the galactic field over timescales $\\ll 1$ Gyr; and that newborn stars follow an initial mass function (IMF) with a distinct peak in the range $0.1 - 1$ $M_\\odot$, rather than an IMF dominated by brown dwarfs. In this review we summarize current observational constraints and theoretical models for the complex interplay between clustered star formation and feedback.

  19. Supernova Feedback Keeps Galaxies Simple

    CERN Document Server

    Chakraborti, Sayan

    2011-01-01

    Galaxies evolve continuously under the influence of self-gravity, rotation, accretion, mergers and feedback. The currently favored cold dark matter cosmological framework, suggests a hierarchical process of galaxy formation, wherein the present properties of galaxies are decided by their individual histories of being assembled from smaller pieces. However, recent studies have uncovered surprising correlations among the properties of galaxies, to the extent of forming a one-parameter set lying on a single fundamental line. It has been argued in the literature that such simplicity is hard to explain within the paradigm of hierarchical galaxy mergers. One of the puzzling results, is the simple linear correlation between the neutral hydrogen mass and the surface area, implying that widely different galaxies share very similar neutral hydrogen surface densities. In this work we show that self-regulated star formation, driven by the competition between gravitational instabilities and mechanical feedback from supern...

  20. Feedback Practices and Signature Pedagogies: What Can the Liberal Arts Learn from the Design Critique?

    Science.gov (United States)

    Schrand, Tom; Eliason, John

    2012-01-01

    To examine the differences between feedback practices in liberal arts courses and in design courses, we surveyed 373 students with experiences of both. Our study found that students perceived the feedback they received in design courses as more effective in advancing their learning, and that the emotional effects of feedback presented verbally and…

  1. Novel tactile feedback to reduce overt stuttering.

    Science.gov (United States)

    Waddell, Dwight E; Goggans, Paul M; Snyder, Gregory J

    2012-08-22

    Stuttering is generally considered to be a speech disorder that affects ∼1% of the global population. Various forms of speech feedback have been shown to reduce overt stuttered speaking, and in particular, second speech signal through speech feedback has drastically reduced utterances of stuttered speech in adults with persistent stuttering. This study reports data for increased overt fluency of speech in an adult stuttering population, whereby the vocalization of the speaker is captured by a microphone or an accelerometer, signal processed, and returned as mechanical tactile speech feedback to the speaker's skin. A repeated measures analysis of variance was used to show that both the microphone and the accelerometer speaking conditions were significantly more fluent than a control (no feedback) condition, with the microphone-driven tactile feedback reducing instances of stuttering by 71% and the accelerometer-driven tactile feedback reducing instances of stuttering by 80%. It is apparent that self-generated tactile feedback can be used to enhance fluency significantly in those who stutter.

  2. NAIP 2015 Imagery Feedback

    Data.gov (United States)

    Farm Service Agency, Department of Agriculture — The NAIP 2015 Imagery Feedback web application allows users to make comments and observations about the quality of the 2015 National Agriculture Imagery Program...

  3. NAIP 2014 Imagery Feedback

    Data.gov (United States)

    Farm Service Agency, Department of Agriculture — The NAIP 2014 Imagery Feedback map allows users to make comments and observations about the quality of the 2014 National Agriculture Imagery Program (NAIP)...

  4. Relaxation oscillations and hierarchy of feedbacks in MAPK signaling

    Science.gov (United States)

    Kochańczyk, Marek; Kocieniewski, Paweł; Kozłowska, Emilia; Jaruszewicz-Błońska, Joanna; Sparta, Breanne; Pargett, Michael; Albeck, John G.; Hlavacek, William S.; Lipniacki, Tomasz

    2017-01-01

    We formulated a computational model for a MAPK signaling cascade downstream of the EGF receptor to investigate how interlinked positive and negative feedback loops process EGF signals into ERK pulses of constant amplitude but dose-dependent duration and frequency. A positive feedback loop involving RAS and SOS, which leads to bistability and allows for switch-like responses to inputs, is nested within a negative feedback loop that encompasses RAS and RAF, MEK, and ERK that inhibits SOS via phosphorylation. This negative feedback, operating on a longer time scale, changes switch-like behavior into oscillations having a period of 1 hour or longer. Two auxiliary negative feedback loops, from ERK to MEK and RAF, placed downstream of the positive feedback, shape the temporal ERK activity profile but are dispensable for oscillations. Thus, the positive feedback introduces a hierarchy among negative feedback loops, such that the effect of a negative feedback depends on its position with respect to the positive feedback loop. Furthermore, a combination of the fast positive feedback involving slow-diffusing membrane components with slower negative feedbacks involving faster diffusing cytoplasmic components leads to local excitation/global inhibition dynamics, which allows the MAPK cascade to transmit paracrine EGF signals into spatially non-uniform ERK activity pulses.

  5. An On-Line Modeling Based Kalman Filtering Process for Time-Interval-Variable Sequences with Application to Astronomic Surveying

    Institute of Scientific and Technical Information of China (English)

    韩建国; 孙才红; 李彦琴

    2003-01-01

    The problem of variable sampling time interval which appears in application of Kalman Filtering is analyzed and the corresponding filtering process with or without present transition matrix is suggested, then an application experiment for astronomical surveying is introduced. In this process, the known stochastically variable sampling time intervals play the roles as deterministic input sequences of the state-space description, and the corresponding matrix and (if needed) state transition matrix can be established by performing real-time and structure-linear system identification.

  6. Frequency and precision of feedback and the adaptive process of learning a dual motor task Frecuencia y necesidad de feedback en el proceso adaptativo de aprendizaje de una tarea motora dual Frequência e precisão de "feedback" e o processo adaptativo de aprendizagem de uma tarefa motora de dupla demanda

    Directory of Open Access Journals (Sweden)

    Cássio Miranda Meira Junior

    2012-09-01

    Full Text Available This work investigated the effects of frequency and precision of feedback on the learning of a dual-motor task. One hundred and twenty adults were randomly assigned to six groups of different knowledge of results (KR, frequency (100%, 66% or 33% and precision (specific or general levels. In the stabilization phase, participants performed the dual task (combination of linear positioning and manual force control with the provision of KR. Ten non-KR adaptation trials were performed for the same task, but with the introduction of an electromagnetic opposite traction force. The analysis showed a significant main effect for frequency of KR. The participants who received KR in 66% of the stabilization trials showed superior adaptation performance than those who received 100% or 33%. This finding reinforces that there is an optimal level of information, neither too high nor too low, for motor learning to be effective.El presente estudio investigó los efectos de la frecuencia y necesidad de feedback en el aprendizaje de una tarea motora de dupla demanda. 120 adultos fueron aleatoriamente designados a seis grupos de diferentes niveles de frecuencia (100%, 66% o 33% y necesidad (específico o general de conocimiento de resultados (CR. En la fase de estabilización, la tarea de posicionamiento lineal y control de fuerza manual fue ejecutada con CR. Diez tentativas de adaptación sin CR fueron ejecutadas durante la misma tarea, con la introducción de una fuerza electromagnética contraria a la dirección del movimiento. El análisis indicó efecto significativo en el factor "Frecuencia de CR": aquellos que recibieron CR en 66% de las tentativas de estabilización obtuvieron desempeño de adaptación superior cuando comparados a aquellos que recibieron 100% o 33% de CR. Ese resultado refuerza la existencia de un nivel óptimo de información, ni muy alto ni muy bajo, para que el aprendizaje sea optimizado.O presente estudo investigou os efeitos da frequ

  7. Feedback and rewards, part II: formal and informal feedback reviews.

    Science.gov (United States)

    Harolds, Jay

    2013-02-01

    There are 2 major classes of feedback. One class of feedback consists of the informal, numerous conversations between various people in the organization regarding the performance, behavior, and goals of an individual. Another class of feedback consists of formal reviews held once or twice a year between a supervisor and an individual. This article discusses both types of feedback.

  8. The Role of Feedback and Social Presence in an Online Peer Coaching Program for Student Teachers

    Science.gov (United States)

    Thurlings, Marieke; Vermeulen, Marjan; Bastiaens, Theo; Stijnen, Sjef

    2014-01-01

    Feedback is essential in any kind of learning. This study focused on feedback in online learning and conceptualized feedback as a social interaction process. Online learning rests on social interaction, which is affected by feelings of social presence. Therefore, we investigated received and perceived online feedback, and the coherence between…

  9. Effects of Feedback on Collaborative Writing in an Online Learning Environment

    Science.gov (United States)

    Guasch, Teresa; Espasa, Anna; Alvarez, Ibis M.; Kirschner, Paul A.

    2013-01-01

    The need for supporting student writing has received much attention in writing research. One specific type of support is feedback--including peer feedback--on the writing process. Despite the wealth of literature on both feedback and academic writing, there is little empirical evidence on what type of feedback best promotes writing in online…

  10. Wind-Speed—Surface-Heat-Flux Feedback in Dust Devils

    Science.gov (United States)

    Ito, Junshi; Niino, Hiroshi

    2016-06-01

    Strong winds associated with dust devils can induce locally large heat fluxes from the surface, and resulting enhanced buoyancy may further intensify the dust devils. This positive wind—surface-heat-flux feedback is studied using a large-eddy simulation of a convective boundary layer. A comparison of the results with and without the feedback process for the same environment demonstrates the significance of the feedback process for simulated dust devils.

  11. Quantifying Contributions of Climate Feedbacks to Global Warming Pattern Formation

    Science.gov (United States)

    Song, X.; Zhang, G. J.; Cai, M.

    2013-12-01

    The ';';climate feedback-response analysis method'' (CFRAM) was applied to the NCAR CCSM3.0 simulation to analyze the strength and spatial distribution of climate feedbacks and to quantify their contributions to global and regional surface temperature changes in response to a doubling of CO2. Instead of analyzing the climate sensitivity, the CFRAM directly attributes the temperature change to individual radiative and non-radiative feedbacks. The radiative feedback decomposition is based on hourly model output rather than monthly mean data that are commonly used in climate feedback analysis. This gives a more accurate quantification of the cloud and albedo feedbacks. The process-based decomposition of non-radiative feedback enables us to understand the roles of GCM physical and dynamic processes in climate change. The pattern correlation, the centered root-mean-square (RMS) difference and the ratio of variations (represented by standard deviations) between the partial surface temperature change due to each feedback process and the total surface temperature change in CCSM3.0 simulation are examined to quantify the roles of each feedback process in the global warming pattern formation. The contributions of climate feedbacks to the regional warming are also discussed.

  12. On Digital Surveying and Mapping Process%浅谈数字化测图过程

    Institute of Scientific and Technical Information of China (English)

    孙源鑫

    2015-01-01

    随着计算机技术的革新及飞速发展,数字化已成为当代社会经济可持续发展的焦点之一。数字化制图及信息系统的建立,对测绘行业提出了更高的要求,原始的手工作业方法已经远远满足不了当今社会发展的需求。%With the innovation and rapid development of computer technology, digitization has become one of the focus of the contemporary social and economic sustainable development. The establishment of digital surveying and mapping and information system has put forward higher requirements for surveying and mapping industry. The original manual work method is far from meeting the demand in today's social development.

  13. The Effect of Information Feedback in Construction Bidding

    Directory of Open Access Journals (Sweden)

    Alexander Soo

    2010-07-01

    Full Text Available  With the goal to achieve efficiency in bidding competitions, many codes of bidding procedure recommend clients provide contractors with bidding feedback information. Contractors strive to bid competitively via learning based on their experiences in past bidding attempts. The level of bidding feedback information, however, varies across clients. In many cases, clients do not provide feedback or provide insufficient feedback to contractors. Focussing on two information feedback conditions (full and partial, we examine: (i the changes in bidding trend over time, and (ii the effects of bidding feedback information on bidders’ competitiveness in bidding. Data were gathered using a bidding experiment that involved student (inexperienced bidders with a construction project management background. The results show that the variations in bids over time for full information feedback condition are statistically significant, but not for bids from bidders with partial bidding feedback information. Bidders with full bidding feedback information are more competitive than those with partial bidding feedback information. The findings add to both our theoretical and empirical understanding of construction bidding: an understanding of the process of changes in the price of building work, and how the process can be manipulated through the release of bidding feedback information.

  14. A student-centred feedback model for educators.

    Science.gov (United States)

    Rudland, Joy; Wilkinson, Tim; Wearn, Andy; Nicol, Pam; Tunny, Terry; Owen, Cathy; O'Keefe, Maree

    2013-04-01

    Effective feedback is instrumental to effective learning. Current feedback models tend to be educator driven rather than learner-centred, with the focus on how the supervisor should give feedback rather than on the role of the learner in requesting and responding to feedback. An alternative approach emphasising the theoretical principles of student-centred and self-regulated learning is offered, drawing upon the literature and also upon the experience of the authors. The proposed feedback model places the student in the centre of the feedback process, and stresses that the attainment of student learning outcomes is influenced by the students themselves. This model emphasises the attributes of the student, particularly responsiveness, receptiveness and reflection, whilst acknowledging the important role that the context and attributes of the supervisor have in influencing the quality of feedback. Educational institutions should consider strategies to encourage and enable students to maximise the many feedback opportunities available to them. As a minimum, educators should remind students about their central role in the feedback process, and support them to develop confidence in meeting this role. In addition, supervisors may need support to develop the skills to shift the balance of responsibility and support students in precipitating feedback moments. Research is also required to validate the proposed model and to determine how to support students to adopt self-regulatory learning, with feedback as a central platform. © Blackwell Publishing Ltd 2013.

  15. The Gaia-ESO Survey: processing of the FLAMES-UVES spectra

    CERN Document Server

    Sacco, G G; Franciosini, E; Maiorca, E; Randich, S; Modigliani, A; Gilmore, G; Asplund, M; Binney, J; Bonifacio, P; Drew, J; Feltzing, S; Ferguson, A; Jeffries, R; Micela, G; Negueruela, I; Prusti, T; Rix, H -W; Vallenari, A; Alfaro, E; Prieto, C Allende; Babusiaux, C; Bensby, T; Blomme, R; Bragaglia, A; Flaccomio, E; Francois, P; Hambly, N; Irwin, M; Koposov, S; Korn, A; Lanzafame, A; Pancino, E; Recio-Blanco, A; Smiljanic, R; Van Eck, S; Walton, N; Bergemann, M; Costado, M T; de Laverny, P; Heiter, U; Hill, V; Hourihane, A; Jackson, R; Jofre, P; Lewis, J; Lind, K; Lardo, C; Magrini, L; Masseron, T; Prisinzano, L; Worley, C

    2014-01-01

    The Gaia-ESO Survey is a large public spectroscopic survey that aims to derive radial velocities and fundamental parameters of about 10^5 Milky Way stars in the field and in clusters. Observations are carried out with the multi-object optical spectrograph FLAMES, using simultaneously the medium resolution (R~20,000) GIRAFFE spectrograph and the high resolution (R~47,000) UVES spectrograph. In this paper, we describe the methods and the software used for the data reduction, the derivation of the radial velocities, and the quality control of the FLAMES-UVES spectra. Data reduction has been performed using a workflow specifically developed for this project. This workflow runs the ESO public pipeline optimizing the data reduction for the Gaia-ESO Survey, performs automatically sky subtraction, barycentric correction and normalisation, and calculates radial velocities and a first guess of the rotational velocities. The quality control is performed using the output parameters from the ESO pipeline, by a visual insp...

  16. Survey of the US materials processing and manufacturing in space program

    Science.gov (United States)

    Mckannan, E. C.

    1981-01-01

    To promote potential commercial applications of low-g technology, the materials processing and manufacturing in space program is structured to: (1) analyze the scientific principles of gravitational effects on processes used in producing materials; (2) apply the research toward the technology used to control production process (on Earth or in space, as appropriate); and (3) establish the legal and managerial framework for commercial ventures. Presently federally funded NASA research is described as well as agreements for privately funded commercial activity, and a proposed academic participation process. The future scope of the program and related capabilities using ground based facilities, aircraft, sounding rockets, and space shuttles are discussed. Areas of interest described include crystal growth; solidification of metals and alloys; containerless processing; fluids and chemical processes (including biological separation processes); and processing extraterrestrial materials.

  17. Malaysian Tertiary Level ESL Students’ Perceptions toward Teacher Feedback, Peer Feedback and Self-assessment in their Writing

    Directory of Open Access Journals (Sweden)

    Kayatri Vasu

    2016-09-01

    Full Text Available In Malaysia, teacher feedback is highly preferred by students, who often believe that teachers know best. Teacher feedback shows them their teacher’s idea of an ideal writing. However, excessive dependence on teachers adds to their workload. Therefore, teachers are increasingly promoting two other alternative methods that are gradually gaining importance. These methods are peer feedback and self-assessment. This study investigates ESL students’ perceptions toward teacher feedback, peer feedback and self-assessment in students’ writing process. Questionnaires, adapted from the instruments in the literature, were administered to 107 randomly selected students in a private local university in Malaysia. Students found feedback given to the content and organization of their writing more useful than feedback provided for their vocabulary and grammar. It was also found that students perceived feedback from teacher, peers and self-assessment all as highly useful. Additionally the results indicated while there was no significant difference (p > .05 between the students’ perceptions toward teacher feedback and self-assessment, they were both perceived as significantly more useful (p < .001 than peer feedback. The students also perceived explicit feedback as significantly more useful (p < .001 than implicit feedback. The results of this study have implications for English language learning-teaching practitioners and researchers. They shed light on the options preferred by students in revising their writing in ESL writing classrooms. Future research on the effects of teacher feedback, peer feedback and self-assessment on students’ writing performance will provide better insight on the preferred methods in ESL writing classrooms in similar settings. Keywords: English as a Second Language, Writing; Teacher Feedback; Peer Feedback; Self-Assessment; Students’ Perceptions

  18. A Survey on Optimal Signal Processing Techniques Applied to Improve the Performance of Mechanical Sensors in Automotive Applications

    Science.gov (United States)

    Hernandez, Wilmar

    2007-01-01

    In this paper a survey on recent applications of optimal signal processing techniques to improve the performance of mechanical sensors is made. Here, a comparison between classical filters and optimal filters for automotive sensors is made, and the current state of the art of the application of robust and optimal control and signal processing techniques to the design of the intelligent (or smart) sensors that today's cars need is presented through several experimental results that show that the fusion of intelligent sensors and optimal signal processing techniques is the clear way to go. However, the switch between the traditional methods of designing automotive sensors and the new ones cannot be done overnight because there are some open research issues that have to be solved. This paper draws attention to one of the open research issues and tries to arouse researcher's interest in the fusion of intelligent sensors and optimal signal processing techniques.

  19. A survey of formal business process verification : From soundness to variability

    NARCIS (Netherlands)

    Groefsema, Heerko; Bucur, Doina

    2013-01-01

    Formal verification of business process models is of interest to a number of application areas, including checking for basic process correctness, business compliance, and process variability. A large amount of work on these topics exist, while a comprehensive overview of the field and its directions

  20. Feedback and rewards, Part I: Introduction to effective feedback.

    Science.gov (United States)

    Harolds, Jay A

    2013-01-01

    This series of articles discusses conversations regarding feedback. Feedback can include input from numerous sources, including one's supervisor, peers, subordinates, suppliers, customers, patients, and/or society members. Effective feedback is very important to the operation of any organization and to the growth of the individual. However, feedback done poorly does not appear to be rare and can be highly destructive to all. A variety of tips on how to do feedback well are included in this article.

  1. Making sense of sexual orientation measures: findings from a cognitive processing study with adolescents on health survey questions.

    Science.gov (United States)

    Austin, S Bryn; Conron, Kerith; Patel, Aarti; Freedner, Naomi

    2007-01-01

    To carry out a study using cognitive processing interview methods to explore ways in which adolescents understand sexual orientation questions currently used on epidemiologic surveys. In-depth, individual interviews were conducted to probe cognitive processes involved in answering four self-report survey questions assessing sexual identity, sexual attraction, and sex of sexual partners.A semi-structured interview guide was used to explore variation in question interpretation, information retrieval patterns and problems, item clarity, valence of reactions to items (positive, negative, neutral), respondent burden, and perceived threat associated with the measures. Thirty adolescents aged 15 to 21 of diverse sexual orientations and race/ethnicities participated in the study, including female, male, and transgender youth. A question on sexual attraction was the most consistently understood and thus was easy for nearly all youth to answer. In contrast, a measure of sexual identity with options heterosexual, bisexual, gay/lesbian, and unsure was the most difficult to answer. Most preferred a sexual identity item that also provided the intermediate options mostly heterosexual and mostly homosexual, which many said reflected their experience of feeling between categories. Participants had varying and inconsistent interpretations of sexual behavior terms, such as sex and sexual intercourse, used in assessing the sex of sexual partners. Differences in understanding could affect interpretation of survey data in important ways. Development of valid measures of sexual orientation will be essential to better monitor health disparities.

  2. Feedback: Now with Physics

    Science.gov (United States)

    Hopkins, Philip F.; Quataert, Eliot; Faucher-Giguere, Claude-Andre; Keres, Dusan; Wetzel, Andrew R.; Murray, Norman W.

    2017-01-01

    The most fundamental unsolved problems in galaxy formation revolve around "feedback" from massive stars and black holes. In the last few years, a new generation of theoretical models have emerged which combine new numerical methods and physics in an attempt to realistically model the diverse physics of the interstellar medium, star formation, and feedback from super-massive black holes and massive stars (winds, jets, SNe, and radiation). These mechanisms lead to 'self-regulated' galaxy and star formation, in which global correlations such as the Schmidt-Kennicutt law, the inefficiency of star formation, and the stellar mass function -- emerge naturally. Within galaxies, feedback regulates the structure of the interstellar medium, and many observed properties of the ISM, star formation, and galaxies can be understood as a fundamental consequence of super-sonic turbulence in a rapidly cooling, self-gravitating medium. But feedback also produces galactic super-winds that can dramatically alter the cosmological evolution of galaxies, change the nature of dark matter cores and ‘cusps’, and re-structure the circum-galactic and inter-galactic medium. These winds depend non-linearly on multiple feedback mechanisms in a way that explains why they have been so difficult to model in previous "sub-grid" approaches. This resolves long-standing problems in understanding even apparently "simple" galaxy properties like the mass-metallicity relation. Finally, I'll discuss where feedback fails, and where either additional, exotic physics, or new, previously-dismissed feedback mechanisms, may be needed to explain observations.

  3. PEACE: Pulsar Evaluation Algorithm for Candidate Extraction -- A software package for post-analysis processing of pulsar survey candidates

    CERN Document Server

    Lee, K J; Jenet, F A; Martinez, J; Dartez, L P; Mata, A; Lunsford, G; Cohen, S; Biwer, C M; Rohr, M; Flanigan, J; Walker, A; Banaszak, S; Allen, B; Barr, E D; Bhat, N D R; Bogdanov, S; Brazier, A; Camilo, F; Champion, D J; Chatterjee, S; Cordes, J; Crawford, F; Deneva, J; Desvignes, G; Ferdman, R D; Freire, P; Hessels, J W T; Karuppusamy, R; Kaspi, V M; Knispel, B; Kramer, M; Lazarus, P; Lynch, R; Lyne, A; McLaughlin, M; Ransom, S; Scholz, P; Siemens, X; Spitler, L; Stairs, I; Tan, M; van Leeuwen, J; Zhu, W W

    2013-01-01

    Modern radio pulsar surveys produce a large volume of prospective candidates, the majority of which are polluted by human-created radio frequency interference or other forms of noise. Typically, large numbers of candidates need to be visually inspected in order to determine if they are real pulsars. This process can be labor intensive. In this paper, we introduce an algorithm called PEACE (Pulsar Evaluation Algorithm for Candidate Extraction) which improves the efficiency of identifying pulsar signals. The algorithm ranks the candidates based on a score function. Unlike popular machine-learning based algorithms, no prior training data sets are required. This algorithm has been applied to data from several large-scale radio pulsar surveys. Using the human-based ranking results generated by students in the Arecibo Remote Command enter programme, the statistical performance of PEACE was evaluated. It was found that PEACE ranked 68% of the student-identified pulsars within the top 0.17% of sorted candidates, 95% ...

  4. A Survey Study of Institutional Review Board Thought Processes in the United States and South Korea

    Directory of Open Access Journals (Sweden)

    Si-Kyung Jung

    2012-09-01

    Full Text Available Introduction: In the last several decades, South Korea has rapidly adopted Western customs and practices. Yet, cultural differences between South Korea and the United States exist. The purpose ofthis study was to identify and characterize potential cultural differences in the Korean and US institutional review board (IRB approach to certain topics.Methods: A qualitative analysis of a 9-item survey, describing 4 research study case scenarios, sent to IRB members from the United States and South Korea. The case scenarios involved the followingissues: (1 the need for consent for retrospective chart review when research subjects receive their care after the study is conceived; (2 child assent; (3 individual versus population benefit; and (4 exception from informed consent in emergency resuscitation research. The free-text responses were analyzed and abstracted for recurrent themes.Results: Twenty-three of the 45 survey recipients completed the survey, for an overall response rate of 51%. The themes that emerged were as follows: (1 the importance of parental authority among Korean participants versus the importance of child autonomy and child assent among US participants; (2 the recognition of the rights of a proxy or surrogate who can represent an individual’s values by all participants; and (3 the importance of the community, expressed by the Korean respondents, versus individualism, expressed by US respondents.Conclusion: Whereas US participants appear to emphasize the importance of the individual and the autonomy of a child, the Korean respondents stressed the importance of parental authority andbenefiting the community, above and beyond that of the individual person. However, there was substantial overlap in the themes expressed by respondents from both countries.

  5. Feedback control of quantum system

    Institute of Scientific and Technical Information of China (English)

    DONG Dao-yi; CHEN Zong-hai; ZHANG Chen-bin; CHEN Chun-lin

    2006-01-01

    Feedback is a significant strategy for the control of quantum system.Information acquisition is the greatest difficulty in quantum feedback applications.After discussing several basic methods for information acquisition,we review three kinds of quantum feedback control strategies:quantum feedback control with measurement,coherent quantum feedback,and quantum feedback control based on cloning and recognition.The first feedback strategy can effectively acquire information,but it destroys the coherence in feedback loop.On the contrary,coherent quantum feedback does not destroy the coherence,but the capability of information acquisition is limited.However,the third feedback scheme gives a compromise between information acquisition and measurement disturbance.

  6. A national survey of admissions criteria and processes in selected allied health professions.

    Science.gov (United States)

    Scott, A H; Chase, L M; Lefkowitz, R; Morton-Rias, D; Chambers, C; Joe, J; Holmes, G; Bloomberg, S

    1995-01-01

    A national survey of admissions criteria and procedures was conducted for allied health programs in diagnostic medical imaging, health information management, nurse-midwifery, occupational therapy, physical therapy, and physician assistant education. From a sample of 462, 63.2% responded. The survey canvassed general program information, prerequisites, admissions procedures, and demographic trends. Respondents were primarily from public institutions with faculty actively involved in admissions. The most common prerequisites were anatomy/physiology, physics, biology, chemistry, and psychology; and the most frequently required admissions criteria were GPA, references, interviews, science GPA, and writing sample. Standardized tests were rarely utilized. The following were the major prerequisite characteristics and skills considered: academic skills, communication skills, problem-solving abilities, maturity/confidence, motivation, and work/study habits. Changing demographics were reported, including an increase in second-career, older, and ethnically diverse applicants. Also discussed were nontraditional and minority applicant admissions issues. Future research suggestions include use of noncognitive variables, and academic and clinical outcome studies. The utility of this information for validation/revision of admissions criteria are presented.

  7. Gender differences in reward and punishment for monetary and social feedback in children: An ERP study

    Science.gov (United States)

    Zou, Yuchen; Song, Yan; Xiao, Xue; Huang, Wanyi; Li, Yanfang

    2017-01-01

    Gender differences in feedback processing have been observed among adolescents and adults through event-related potentials. However, information on whether and how this feedback processing is affected by feedback valence, feedback type, and individual sensitivity in reward/punishment among children remains minimal. In this study, we used a guessing game task coupled with electroencephalography to investigate gender differences in feedback processing, in which feedback to reward and punishment was presented in the context of monetary and social conditions. Results showed that boys were less likely to switch their response after punishment, had generally less feedback-related negativity (FRN) amplitude, and longer FRN latency in monetary and punishment conditions than girls. Moreover, FRN for monetary punishment, which is related to individual difference in reward sensitivity, was observed only in girls. The study provides gender-specific evidence for the neural processing of feedback, which may offer educational guidance for appropriate feedback for girls and boys. PMID:28346515

  8. 2013 mask industry survey

    Science.gov (United States)

    Malloy, Matt

    2013-09-01

    A comprehensive survey was sent to merchant and captive mask shops to gather information about the mask industry as an objective assessment of its overall condition. 2013 marks the 12th consecutive year for this process. Historical topics including general mask profile, mask processing, data and write time, yield and yield loss, delivery times, maintenance, and returns were included and new topics were added. Within each category are multiple questions that result in a detailed profile of both the business and technical status of the mask industry. While each year's survey includes minor updates based on feedback from past years and the need to collect additional data on key topics, the bulk of the survey and reporting structure have remained relatively constant. A series of improvements is being phased in beginning in 2013 to add value to a wider audience, while at the same time retaining the historical content required for trend analyses of the traditional metrics. Additions in 2013 include topics such as top challenges, future concerns, and additional details in key aspects of mask masking, such as the number of masks per mask set per ground rule, minimum mask resolution shipped, and yield by ground rule. These expansions beyond the historical topics are aimed at identifying common issues, gaps, and needs. They will also provide a better understanding of real-life mask requirements and capabilities for comparison to the International Technology Roadmap for Semiconductors (ITRS).

  9. Effects of Performance Feedback and Coaching on the Problem-Solving Process: Improving the Integrity of Implementation and Enhancing Student Outcomes

    Science.gov (United States)

    Lundahl, Allison A.

    2010-01-01

    Schools implementing Response to Intervention (RtI) procedures frequently engage in team problem-solving processes to address the needs of students who require intensive and individualized services. Because the effectiveness of the problem-solving process will impact the overall success of RtI systems, the present study was designed to learn more…

  10. A novel Minute Feedback System for medical students.

    Science.gov (United States)

    Hughes, David T; Leininger, Lisa; Reddy, Rishindra M; Sandhu, Gurjit; Ryszawa, Susan; Englesbe, Michael

    2017-02-01

    Medical students often report a lack of timely, useful feedback during clerkship rotations. The purpose of this study was to develop a novel Minute Feedback System and determine whether it would generate frequent, high quality, documented feedback for students during the third year surgery clerkship. The Minute Feedback System was created using the Qualtrics(©) survey software platform and piloted with surgery clerkship students. These students were surveyed about the frequency and quality of feedback and their overall rating of the surgery clerkship and compared to students who did not use the feedback system. The initial pilot of the Minute Feedback System involved 6/34 M3 surgery clerkship students and generated a total of 70 unique comments from faculty and residents over 3 weeks. When the 6 pilot students were compared to the 28 students without access to the Minute Feedback System, they respectively rated the frequency of feedback 4.50 vs 2.83 (p < 0.01); the quality of feedback 4.70 vs 3.33 (p < 0.01) and the overall rating of the surgery clerkship 4.67 vs 4.05 (p < 0.01) higher. The system was then made available to all students on the M3 surgery clerkship (n = 31) over the subsequent 2 month rotation. 354 unique feedback comments were generated from 399 student requests (89% response rate). Students using the Minute Feedback System (n = 31) compared to students in the previous academic year without (n = 170) rated the quality of feedback (3.76 vs 3.4, p < 0.01), that feedback was provided during clerkship (100% vs 90%, p < 0.01) and the overall quality of the clerkship (3.94 vs 3.87, p = 0.2) higher. The novel Minute Feedback System allows for frequent, timely, useful and documented feedback to medical students. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Strategies in probabilistic feedback learning in Parkinson patients OFF medication.

    Science.gov (United States)

    Bellebaum, C; Kobza, S; Ferrea, S; Schnitzler, A; Pollok, B; Südmeyer, M

    2016-04-21

    Studies on classification learning suggested that altered dopamine function in Parkinson's Disease (PD) specifically affects learning from feedback. In patients OFF medication, enhanced learning from negative feedback has been described. This learning bias was not seen in observational learning from feedback, indicating different neural mechanisms for this type of learning. The present study aimed to compare the acquisition of stimulus-response-outcome associations in PD patients OFF medication and healthy control subjects in active and observational learning. 16 PD patients OFF medication and 16 controls were examined with three parallel learning tasks each, two feedback-based (active and observational) and one non-feedback-based paired associates task. No acquisition deficit was seen in the patients for any of the tasks. More detailed analyses on the learning strategies did, however, reveal that the patients showed more lose-shift responses during active feedback learning than controls, and that lose-shift and win-stay responses more strongly determined performance accuracy in patients than controls. For observational feedback learning, the performance of both groups correlated similarly with the performance in non-feedback-based paired associates learning and with the accuracy of observed performance. Also, patients and controls showed comparable evidence of feedback processing in observational learning. In active feedback learning, PD patients use alternative learning strategies than healthy controls. Analyses on observational learning did not yield differences between patients and controls, adding to recent evidence of a differential role of the human striatum in active and observational learning from feedback.

  12. Feedback-related brain activity predicts learning from feedback in multiple-choice testing.

    Science.gov (United States)

    Ernst, Benjamin; Steinhauser, Marco

    2012-06-01

    Different event-related potentials (ERPs) have been shown to correlate with learning from feedback in decision-making tasks and with learning in explicit memory tasks. In the present study, we investigated which ERPs predict learning from corrective feedback in a multiple-choice test, which combines elements from both paradigms. Participants worked through sets of multiple-choice items of a Swahili-German vocabulary task. Whereas the initial presentation of an item required the participants to guess the answer, corrective feedback could be used to learn the correct response. Initial analyses revealed that corrective feedback elicited components related to reinforcement learning (FRN), as well as to explicit memory processing (P300) and attention (early frontal positivity). However, only the P300 and early frontal positivity were positively correlated with successful learning from corrective feedback, whereas the FRN was even larger when learning failed. These results suggest that learning from corrective feedback crucially relies on explicit memory processing and attentional orienting to corrective feedback, rather than on reinforcement learning.

  13. Radiative feedback from ionized gas

    CERN Document Server

    Glover, S C O

    2007-01-01

    H2 formation in metal-free gas occurs via the intermediate H- or H2+ ions. Destruction of these ions by photodissociation therefore serves to suppress H2 formation. In this paper, I highlight the fact that several processes that occur in ionized primordial gas produce photons energetic enough to photodissociate H- or H2+ and outline how to compute the photodissociation rates produced by a particular distribution of ionized gas. I also show that there are circumstances of interest, such as during the growth of HII regions around the first stars, in which this previously overlooked form of radiative feedback is of considerable importance.

  14. Jointly amplified basal and pulsatile growth hormone (GH) secretion and increased process irregularity in women with anorexia nervosa: indirect evidence for disruption of feedback regulation within the GH-insulin-like growth factor I axis

    DEFF Research Database (Denmark)

    Støving, R K; Veldhuis, J D; Flyvbjerg, A;

    1999-01-01

    pulsatility in AN using the techniques of deconvolution analysis and approximate entropy, which quantify secretory activity and serial irregularity of underlying hormone release not reflected in peak occurrence or amplitudes. To this end, 24-h GH profiles were obtained by continuous blood sampling aliquoted...... and the basal as well as pulsatile GH secretion rates. Moreover, AN patients exhibited significantly greater GH approximate entropy scores than the controls, denoting marked irregularity of the GH release process. In contrast to previous reports in healthy fasting subjects, cortisol levels in AN patients were....... Accordingly, GH secretion in AN probably reflects altered neuroendocrine feedback regulation, e.g. associated with increased hypothalamic GHRH discharge superimposed on reduced hypothalamic somatostatinergic tone....

  15. TUNE FEEDBACK AT RHIC

    Energy Technology Data Exchange (ETDEWEB)

    CAMERON,P.; CERNIGLIA,P.; CONNOLLY,R.; CUPOLO,J.; DAWSON,W.C.; DEGEN,C.; DELLAPENNA,A.; DELONG,J.; DREES,A.; HUHN,A.; KESSELMAN,M.; MARUSIC,A.; OERTER,B.; MEAD,J.; SCHULTHEISS,C.; SIKORA,R.; VAN ZEIJTS,J.

    2001-06-18

    Preliminary phase-locked loop betatron tune measurement results were obtained during RHIC 2000 with a resonant Beam Position Monitor. These results suggested the possibility of incorporating PLL tune measurement into a tune feedback system for RHIC 2001. Tune feedback is useful in a superconducting accelerator, where the machine cycle time is long and inefficient acceleration due to resonance crossing is not comfortably tolerated. This is particularly true with the higher beam intensities planned for RHIC 2001. We present descriptions of a PLL tune measurement system implemented in the DSP/FPGA environment of a RHIC BPM electronics module and the feedback system into which the measurement is incorporated to regulate tune. In addition, we present results from the commissioning of this system during RHIC 2001.

  16. Data processing workflows from low-cost digital survey to various applications: three case studies of Chinese historic architecture

    Science.gov (United States)

    Sun, Z.; Cao, Y. K.

    2015-08-01

    The paper focuses on the versatility of data processing workflows ranging from BIM-based survey to structural analysis and reverse modeling. In China nowadays, a large number of historic architecture are in need of restoration, reinforcement and renovation. But the architects are not prepared for the conversion from the booming AEC industry to architectural preservation. As surveyors working with architects in such projects, we have to develop efficient low-cost digital survey workflow robust to various types of architecture, and to process the captured data for architects. Although laser scanning yields high accuracy in architectural heritage documentation and the workflow is quite straightforward, the cost and portability hinder it from being used in projects where budget and efficiency are of prime concern. We integrate Structure from Motion techniques with UAV and total station in data acquisition. The captured data is processed for various purposes illustrated with three case studies: the first one is as-built BIM for a historic building based on registered point clouds according to Ground Control Points; The second one concerns structural analysis for a damaged bridge using Finite Element Analysis software; The last one relates to parametric automated feature extraction from captured point clouds for reverse modeling and fabrication.

  17. THE METHOD OF DATA PROCESSING OF THE ELECTRICAL SURVEYING AND THE PROGRAM SYSTEM USED ON MICROCOMPUTER

    Institute of Scientific and Technical Information of China (English)

    李志聃; 高绋麟

    1990-01-01

    The ESS software package is prepared for electrical data processing in the fields of coal prospecting, hydrogeological engineering, and can be used in the other fields of electrical data processing. It can be operated on any kind of microcomputer which has an internal memories of moro than 512kB. The ESS software package would be leading the office operation to an automatic data processing period and the field work free from the tedious, repeated data treating and mapping, so that the engineers would have more time to analyse and interpret field data. Undoubtedly, it is of benefit to improving the relibility of the geological evaluation.

  18. The interaction between feedback from active galactic nuclei and supernovae

    CERN Document Server

    Booth, C M

    2012-01-01

    Energetic feedback from supernovae (SNe) and from active galactic nuclei (AGN) are both important processes that are thought to control how much gas is able to condense into galaxies and form stars. We show that although both AGN and SNe suppress star formation, they mutually weaken one another's effect by up to an order of magnitude in haloes in the mass range for which both feedback processes are efficient (10^11.25 M_sun < m_200 < 10^12.5 M_sun). These results demonstrate the importance of the simultaneous, non-independent inclusion of these two processes in models of galaxy formation to estimate the total feedback strength. These results are of particular relevance to semi-analytic models, which implicitly assume the effects of the two feedback processes to be independent, and also to hydrodynamical simulations that model only one of the feedback processes.

  19. Climate forcings and feedbacks

    Science.gov (United States)

    Hansen, James

    1993-01-01

    Global temperature has increased significantly during the past century. Understanding the causes of observed global temperature change is impossible in the absence of adequate monitoring of changes in global climate forcings and radiative feedbacks. Climate forcings are changes imposed on the planet's energy balance, such as change of incoming sunlight or a human-induced change of surface properties due to deforestation. Radiative feedbacks are radiative changes induced by climate change, such as alteration of cloud properties or the extent of sea ice. Monitoring of global climate forcings and feedbacks, if sufficiently precise and long-term, can provide a very strong constraint on interpretation of observed temperature change. Such monitoring is essential to eliminate uncertainties about the relative importance of various climate change mechanisms including tropospheric sulfate aerosols from burning of coal and oil smoke from slash and burn agriculture, changes of solar irradiance changes of several greenhouse gases, and many other mechanisms. The considerable variability of observed temperature, together with evidence that a substantial portion of this variability is unforced indicates that observations of climate forcings and feedbacks must be continued for decades. Since the climate system responds to the time integral of the forcing, a further requirement is that the observations be carried out continuously. However, precise observations of forcings and feedbacks will also be able to provide valuable conclusions on shorter time scales. For example, knowledge of the climate forcing by increasing CFC's relative to the forcing by changing ozone is important to policymakers, as is information on the forcing by CO2 relative to the forcing by sulfate aerosols. It will also be possible to obtain valuable tests of climate models on short time scales, if there is precise monitoring of all forcings and feedbacks during and after events such as a large volcanic eruption

  20. The Payout Decision-Making Process of Brazilian Listed Companies: A CFO Survey

    Directory of Open Access Journals (Sweden)

    Roberto Frota Decourt

    2012-12-01

    Full Text Available The purpose of this paper is to present the results of a survey with Brazilian listed companies CFOs` trying to identify how these companies determine and manage their payout policy. It was identified that the final decision about dividends is taken by the board of directors, taking into consideration a management proposal sent to them before. Main factors analyzed are net profit and cash generation during immediate previous period. The managers mainly consider interest on own capital (JSCP and dividends as instruments for payout policy. They believe that share repurchase is advantageous to shareholders; however, it is viewed more as an investment decision by the company than a dividend policy. The interest on own capital is broadly used because it provides a fiscal benefit to the company. It seems that management compensation policy affects dividends payout. This suggests an agency conflict between managers and shareholders.

  1. The Hamburg/ESO R-process Enhanced Star survey (HERES): Abundances

    Science.gov (United States)

    Barklem, P. S.; Christlieb, N.; Beers, T. C.; Hill, V.; Holmberg, J.; Marsteller, B.; Rossi, S.; Zickgraf, F.-J.; Bessell, M. S.

    We present the results of analysis of "snapshot" spectra (i.e., R=20,000 and S/N=50 per pixel) of 253 metal-poor halo stars -3.8[Fe/H] obtained in the HERES survey. The spectra are analysed using an automated line profile analysis method based on the Spectroscopy Made Easy (SME) codes of Valenti & Piskunov (1996). Elemental abundances of moderate precision (absolute r.m.s. errors of order 0.25 dex) have been obtained for 22 elements, C, Mg, Al, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, and Eu, where detectable. The results are presented and discussed, particularly trends and scatter in the abundance distributions.

  2. Naive Architecting - Understanding the Reasoning Process of Students A Descriptive Survey

    NARCIS (Netherlands)

    Heesch, Uwe van; Avgeriou, Paris; Babar, MA; Gorton,

    2010-01-01

    Software architecting entails making architecture decisions, which requires a lot of experience and expertise. Current literature contains several methods and processes to support architects with architecture design, documentation and evaluation but not with the design reasoning involved in

  3. a survey of rice production and processing in south east nigeria

    African Journals Online (AJOL)

    user

    agricultural policy makers device the modalities for improving rice production and processing in the area. ... for rice production and the application method was mostly by manual broad casting over the planted area. ... 1, January 2017 228.

  4. Literature survey of in situ processes for application to the US tar sand resource

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Jr., L. A.

    1989-08-01

    Tar sands in the United States and worldwide are a large potential source of hydrocarbon liquids that has yet to be sufficiently developed. The development of the US tar sand resource lags the worldwide development and poses a challenge that has not been eagerly accepted by the petroleum industry. This paper reviews the developmental status of in situ enhanced oil recovery techniques that have been proposed for the production of heavy oils or bitumen and determines which process or processes are in the forefront for application to the US resource. Also noted is what developmental work, if any, remains to be accomplished before field testing of the process(es). The review used only information available in the public domain. 196 refs., 1 fig., 2 tabs.

  5. Feedback-charging a metallic island

    Science.gov (United States)

    Schaller, Gernot

    2017-03-01

    We consider electronic transport through a single-electron quantum dot that is tunnel-coupled to an electronic lead and a metallic island. A background reservoir keeps the metallic island at a thermal state with the ambient temperature, while the charge accumulated on the island is reflected in a time-dependent chemical potential. Without feedback, a current would flow through the system until the chemical potentials of island and lead are equilibrated. A feedback loop can be implemented by a quantum point contact detecting the dot state, classical processing of the result and appropriate feedback actions on the electronic tunneling rates taken, with the objective to direct the current in a preferred direction. Since we directly take the detector counting statistics into account, this automatically includes measurement errors in the description. When mainly the rates are modified but hardly any energy is exchanged with the system, this feedback loop effectively implements a Maxwell demon, capable of transporting electrons against an electric bias and thereby charging the metallic island. Once the feedback protocol is stopped, the metallic island simply discharges. We find that a quantitative detector model may be useful for a realistic statistical description of feedback loops.

  6. Developing and testing a student-focussed teaching evaluation survey for university instructors.

    Science.gov (United States)

    Ginns, Paul; Barrie, Simon

    2009-06-01

    This paper describes a process for developing a student-focussed survey to gather teaching- and learning-related feedback from university students and examines the psychometric properties of a short survey for confidential feedback to lecturers in higher education regarding teaching. Analyses were performed at the level of individual respondents and on teacher-average responses. Principal component and exploratory factor analyses at both levels indicated a single underlying lecturing effectiveness factor. Scale scores had high internal consistency. The items and subsequent scale were also consistent in terms of interrater reliability, i.e., the average consistency of ratings of an individual lecturer. Finally, at both levels of analysis, strong correlations between responses to each item and an overall rating provided support for the concurrent validity of the items. These analyses provide initial evidence of the suitability of the survey for gathering confidential student feedback on lecturing effectiveness.

  7. Strategies for the management of lecturer stress in feedback tutorials

    OpenAIRE

    Hartney, Elizabeth

    2007-01-01

    Abstract The process of providing students with individual feedback on assessed work was identified as a source of lecturer stress (Stough and Emmer, 1998). An action research approach was used to address the following research question. What approaches to providing students with feedback minimize lecturer stress? Data were collected using written feedback mark-sheets and a reflective diary. Findings indicated that negative expectations, student emotion, challenges from students an...

  8. A Survey of Novel Processes to Produce Ultra Low Sulfur Gasoline

    Institute of Scientific and Technical Information of China (English)

    Xu Yun; Long Jun; Shao Xinjun

    2003-01-01

    The restriction on sulfur level in gasoline has been increasingly tightened. The U.S.Tier Ⅱ regulation requires a reduction from average 340ppm to 30ppm from 2004 to 2008. Recently significant progress has been made in effective high sulfur removal, such as post treatment of FCC gasoline by selective hydrotreating, S Zorb sulfur removal technology, OATS process etc. The sulfur content of FCC gasoline can be deceased to less than 10ppm. With regard to gasoline pool composition in China, it is very important to look for effective desulfurization processes that are simple, straightforward, with less hydrogen consumption. Post-treatment of FCC gasoline is a preferred option. From the point of view of comprehensive utilization, alkylation, polymerization, isomerisation etc. can be added to desulfurization process to meet the requirement of ultra low sulfur, premium.

  9. Survey of knowledge of hazards of chemicals potentially associated with the advanced isotope separation processes

    Energy Technology Data Exchange (ETDEWEB)

    Chester, R.O.; Kirkscey, K.A.; Randolph, M.L.

    1979-09-01

    Hazards of chemical potentially associated with the advanced isotope separation processes are estimated based on open literature references. The tentative quantity of each chemical associated with the processes and the toxicity of the chemical are used to estimate this hazard. The chemicals thus estimated to be the most potentially hazardous to health are fluorine, nitric acid, uranium metal, uranium hexafluoride, and uranium dust. The estimated next most hazardous chemicals are bromine, hydrobromic acid, hydrochloric acid, and hydrofluoric acid. For each of these chemicals and for a number of other process-associated chemicals the following information is presented: (1) any applicable standards, recommended standards and their basis; (2) a brief discussion to toxic effects including short exposure tolerance, atmospheric concentration immediately hazardous to life, evaluation of exposures, recommended control procedures, chemical properties, and a list of any toxicology reviews; and (3) recommendations for future research.

  10. Observations of Protostellar Outflow Feedback in Clustered Star Formation

    CERN Document Server

    Nakamura, Fumitaka

    2015-01-01

    We discuss the role of protostellar outflow feedback in clustered star formation using the observational data of recent molecular outflow surveys toward nearby cluster-forming clumps. We found that for almost all clumps, the outflow momentum injection rate is significantly larger than the turbulence dissipation rate. Therefore, the outflow feedback is likely to maintain supersonic turbulence in the clumps. For less massive clumps such as B59, L1551, and L1641N, the outflow kinetic energy is comparable to the clump gravitational energy. In such clumps, the outflow feedback probably affects significantly the clump dynamics. On the other hand, for clumps with masses larger than about 200 M$_\\odot$, the outflow kinetic energy is significantly smaller than the clump gravitational energy. Since the majority of stars form in such clumps, we conclude that outflow feedback cannot destroy the whole parent clump. These characteristics of the outflow feedback support the scenario of slow star formation.

  11. Feedback i undervisningen

    DEFF Research Database (Denmark)

    Kirkegaard, Preben Olund

    2015-01-01

    undervisningsdifferentiering, feedback på læreprocesser, formativ og summativ evaluering, observationer og analyse af undervisning samt lærernes teamsamarbejde herom. Praktikken udgør et særligt læringsrum i læreruddannelsen. Samspillet mellem studerende, praktiklærere og undervisere giver den studerende en unik mulighed...

  12. Plant–soil feedbacks

    NARCIS (Netherlands)

    Cortois, Roeland; Schröder-Georgi, Thomas; Weigelt, Alexandra; Putten, van der Wim H.; Deyn, De Gerlinde B.

    2016-01-01

    1. Plant–soil feedback (PSF), plant trait and functional group concepts advanced our understanding of plant community dynamics, but how they are interlinked is poorly known.
    2. To test how plant functional groups (FGs: graminoids, small herbs, tall herbs, legumes) and plant traits relate to PSF,

  13. Feedback and Prior Achievement.

    Science.gov (United States)

    Hyman, Cynthia; Tobias, Sigmund

    The hypothesis that feedback in programmed instruction is an important variable in the learning of novel, but not familiar, content was investigated. A linear, constructed response program dealing with the Sabbath rituals in the synagogue was chosen due to wide variability in student familiarity with this topic. Subjects were randomly assigned to…

  14. Review of Assessment Feedback

    Science.gov (United States)

    Li, Jinrui; De Luca, Rosemary

    2014-01-01

    This article reviews 37 empirical studies, selected from 363 articles and 20 journals, on assessment feedback published between 2000 and 2011. The reviewed articles, many of which came out of studies in the UK and Australia, reflect the most current issues and developments in the area of assessing disciplinary writing. The article aims to outline…

  15. Staff survey of organizational structure and process for a Public Health Department.

    Science.gov (United States)

    Dwyer, J J

    1995-01-01

    A survey of 227 North York Public Health Department (NYPHD) staff provided their perspective on the organizational structure. They perceived that (a) the departmental and divisional organizational structures are effective for program delivery, (b) the Central Resources structure and divisional and departmental reporting structures are moderately effective for program delivery, (c) the decentralized office structure is an advantage for service delivery but less so for administration and intra-division and inter-division communication, (d) the mandatory program structure involves low to moderate interdisciplinary teamwork and moderately impacts service delivery, (e) intra-division and management-staff communication are fair but inter-division and office communication are between poor and fair, (f) education, research, and service are moderately integrated, and (g) the divisional and departmental work atmospheres are a little positive. Management perceived greater participation in program planning, more frequent communication with other divisions, a number of education and research opportunities from various divisions/units, and more management recognition than front line staff did.

  16. The Extreme Ice Survey: Capturing and Conveying Glacial Processes Through Time-Lapse Imagery and Narration

    Science.gov (United States)

    Balog, J. D.; Box, J. E.; Pfeffer, W. T.; Hood, E. W.; Fagre, D. B.; Anker, C.; O'Neel, S.

    2010-12-01

    The Extreme Ice Survey (EIS) uses time-lapse photography, conventional photography, and video to document rapid change in the Earth's glacial ice. The EIS team currently has 38 time-lapse cameras at sites in Greenland, Iceland, Alaska, the Rocky Mountains and Nepal. EIS supplements this ongoing record with annual repeat photography in British Columbia, Iceland, the Alps, and Bolivia. EIS imagery supplies basic knowledge in glacier dynamics to the science community, as well as compelling, engaging narratives to the general public about the immediacy of the Anthropocene and climate change. Visual materials from EIS have impacted more than 150 million people, ranging from White House staff, the U. S. Congress and government agency officials to globally influential corporate officers and all age strata of the general public. Media products include a National Geographic/NOVA special, two National Geographic magazine articles, a feature in Parade magazine (circulation 71 million), and numerous presentations on CNN, NBC, BBC and National Public Radio. Columbia Glacier, Alaska, June 2006, May 2007, June 2008 terminus indicated.

  17. [Structure and process quality of multimodal pain therapy. Results of a survey of pain therapy clinics].

    Science.gov (United States)

    Nagel, B; Pfingsten, M; Brinkschmidt, T; Casser, H-R; Gralow, I; Irnich, D; Klimczyk, K; Sabatowski, R; Schiltenwolf, M; Sittl, R; Söllner, W; Arnold, B

    2012-12-01

    Multimodal therapy has demonstrated good clinical effectiveness in the treatment of chronic pain syndromes. However, within the German health system a comprehensive and nationwide access to multimodal therapy is not available and further improvement is therefore necessary. In order to analyze the current status of multimodal therapy and specifically its structural and procedural requirements and qualities, a survey was carried out in 37 pain clinics with established multimodal treatment programs. An anonymous questionnaire was used for data collection. Results demonstrated that a substantial accordance was found between all pain clinics concerning requirements for space, facilities and staff. Structured multidisciplinary assessments were carried out by all pain clinics even though the amount of time allocated for this varied widely. The main focus of multimodal therapy in all facilities was based on a common philosophy with a cognitive-behavioral approach to reduce patient helplessness and avoidance behavior and to increase physical and psychosocial activities as well as to strengthen self-efficacy. Some differences in the ways and means to achieve these goals could be demonstrated in the various programs.

  18. Data processing for the mise-a-la-masse survey; Ryuden den`iho tansa no data shori

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, K.; Mizunaga, H.; Ushijima, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Kaieda, H. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1996-10-01

    Data processing method was studied for mise-a-la-masse survey. Mise-a-la-masse method using wells as current sources measures resultant ground surface potential difference, and detects underground local resistivity anomaly. To extract resistivity anomaly largely different from surroundings, the anomaly is extracted as difference between the estimated value of regular resistivity structure (background) and potential difference or apparent resistivity. The following three approximations were attempted to estimate the background: the theoretical equation assuming isotropic homogeneous resistivity structure, that assuming horizontal multi-layered structure and the exponential function of distance from linear electrode for apparent resistivity, and these were compared with each other by numerical model experiment. The data processing method which determines the resistivity structure of the background and the residual of apparent resistivity distribution by inversion analysis using the above second equation, could precisely extract local resistivity anomaly, and estimate the depth distribution of resistivity. 5 refs., 10 figs., 2 tabs.

  19. IT process architectures for enterprises development: A survey from a maturity model perspective

    NARCIS (Netherlands)

    Santana Tapia, R.G.

    2006-01-01

    During the last years much has been published about IT governance. Close to the success of many governance efforts are the business frameworks, quality models, and technology standards that help enterprises improve processes, customer service, quality of products, and control. In this paper we i) su

  20. IT process architectures for enterprises development: A survey from a maturity model perspective

    NARCIS (Netherlands)

    Santana Tapia, R.G.

    During the last years much has been published about IT governance. Close to the success of many governance efforts are the business frameworks, quality models, and technology standards that help enterprises improve processes, customer service, quality of products, and control. In this paper we i)

  1. A National Research Survey of Technology Use in the BSW Teaching and Learning Process

    Science.gov (United States)

    Buquoi, Brittany; McClure, Carli; Kotrlik, Joseph W.; Machtmes, Krisanna; Bunch, J. C.

    2013-01-01

    The purpose of this descriptive-correlational research study was to assess the overall use of technology in the teaching and learning process (TLP) by BSW educators. The accessible and target population included all full-time, professorial-rank, BSW faculty in Council on Social Work Education--accredited BSW programs at land grant universities.…

  2. SPITZER survey of dust grain processing in stable discs around binary post-AGB stars

    NARCIS (Netherlands)

    Gielen, C.; van Winckel, H.; Min, M.; Waters, L.B.F.M.; Lloyd Evans, T.

    2008-01-01

    Aims. We investigate the mineralogy and dust processing in the circumbinary discs of binary post-AGB stars using high-resolution TIMMI2 and SPITZER infrared spectra. Methods: We perform a full spectral fitting to the infrared spectra using the most recent opacities of amorphous and crystalline dust

  3. Career Services Perspectives on the Use of Portfolios in the Teacher Employment Process: A Survey

    Science.gov (United States)

    Boody, Robert M.

    2009-01-01

    Portfolios are widely required in teacher education programs. One of the rationales often given for their use is their value in the employment process. The issue addressed in this study--the use of portfolios for employment--is separate from the issue of whether portfolios are useful for teacher credentialing or within a teacher education program…

  4. Using Institutional Survey Data to Jump-Start Your Benchmarking Process

    Science.gov (United States)

    Chow, Timothy K. C.

    2012-01-01

    Guided by the missions and visions, higher education institutions utilize benchmarking processes to identify better and more efficient ways to carry out their operations. Aside from the initial planning and organization steps involved in benchmarking, a matching or selection step is crucial for identifying other institutions that have good…

  5. Supernova Feedback in an Inhomogeneous Interstellar Medium

    CERN Document Server

    Martizzi, Davide; Quataert, Eliot

    2014-01-01

    Supernova (SN) feedback is one of the key processes shaping the interstellar medium (ISM) of galaxies. SNe contribute to (and in some cases may dominate) driving turbulence in the ISM and accelerating galactic winds. Modern cosmological simulations have sufficient resolution to capture the main structures in the ISM of galaxies, but are typically still not capable of explicitly resolving all of the small-scale stellar feedback processes, including the expansion of supernova remnants (SNRs). We perform a series of controlled three-dimensional hydrodynamic (adaptive mesh refinement, AMR) simulations of single SNRs expanding in an inhomogeneous density field with statistics motivated by those of the turbulent ISM. We use these to quantify the momentum and thermal energy injection from SNe as a function of spatial scale and the density, metallicity, and structure of the ambient medium. Using these results, we develop an analytic sub-resolution model for SN feedback for use in galaxy formation simulations. We then...

  6. Fuel Quality/Processing Study. Volume II. Appendix, Task I, literature survey

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, J B; Bela, A; Jentz, N E; Klumpe, H W; Kessler, R E; Kotzot, H T; Loran, B I

    1981-04-01

    This activity was begun with the assembly of information from Parsons' files and from contacts in the development and commercial fields. A further more extensive literature search was carried out using the Energy Data Base and the American Petroleum Institute Data Base. These are part of the DOE/RECON system. Approximately 6000 references and abstracts were obtained from the EDB search. These were reviewed and the especially pertinent documents, approximately 300, were acquired in the form of paper copy or microfiche. A Fuel Properties form was developed for listing information pertinent to gas turbine liquid fuel properties specifications. Fuel properties data for liquid fuels from selected synfuel processes, deemed to be successful candidates for near future commercial plants were tabulated on the forms. The processes selected consisted of H-Coal, SRC-II and Exxon Donor Solvent (EDS) coal liquefaction processes plus Paraho and Tosco shale oil processes. Fuel properties analyses for crude and distillate syncrude process products are contained in Section 2. Analyses representing synthetic fuels given refinery treatments, mostly bench scale hydrotreating, are contained in Section 3. Section 4 discusses gas turbine fuel specifications based on petroleum source fuels as developed by the major gas turbine manufacturers. Section 5 presents the on-site gas turbine fuel treatments applicable to petroleum base fuels impurities content in order to prevent adverse contaminant effects. Section 7 relates the environmental aspects of gas turbine fuel usage and combustion performance. It appears that the near future stationary industrial gas turbine fuel market will require that some of the synthetic fuels be refined to the point that they resemble petroleum based fuels.

  7. Fuel Quality/Processing Study. Volume II. Appendix, Task I, literature survey

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, J B; Bela, A; Jentz, N E; Klumpe, H W; Kessler, R E; Kotzot, H T; Loran, B I

    1981-04-01

    This activity was begun with the assembly of information from Parsons' files and from contacts in the development and commercial fields. A further more extensive literature search was carried out using the Energy Data Base and the American Petroleum Institute Data Base. These are part of the DOE/RECON system. Approximately 6000 references and abstracts were obtained from the EDB search. These were reviewed and the especially pertinent documents, approximately 300, were acquired in the form of paper copy or microfiche. A Fuel Properties form was developed for listing information pertinent to gas turbine liquid fuel properties specifications. Fuel properties data for liquid fuels from selected synfuel processes, deemed to be successful candidates for near future commercial plants were tabulated on the forms. The processes selected consisted of H-Coal, SRC-II and Exxon Donor Solvent (EDS) coal liquefaction processes plus Paraho and Tosco shale oil processes. Fuel properties analyses for crude and distillate syncrude process products are contained in Section 2. Analyses representing synthetic fuels given refinery treatments, mostly bench scale hydrotreating, are contained in Section 3. Section 4 discusses gas turbine fuel specifications based on petroleum source fuels as developed by the major gas turbine manufacturers. Section 5 presents the on-site gas turbine fuel treatments applicable to petroleum base fuels impurities content in order to prevent adverse contaminant effects. Section 7 relates the environmental aspects of gas turbine fuel usage and combustion performance. It appears that the near future stationary industrial gas turbine fuel market will require that some of the synthetic fuels be refined to the point that they resemble petroleum based fuels.

  8. Delayed excitatory and inhibitory feedback shape neural information transmission

    Science.gov (United States)

    Chacron, Maurice J.; Longtin, André; Maler, Leonard

    2017-01-01

    Feedback circuitry with conduction and synaptic delays is ubiquitous in the nervous system. Yet the effects of delayed feedback on sensory processing of natural signals are poorly understood. This study explores the consequences of delayed excitatory and inhibitory feedback inputs on the processing of sensory information. We show, through numerical simulations and theory, that excitatory and inhibitory feedback can alter the firing frequency response of stochastic neurons in opposite ways by creating dynamical resonances, which in turn lead to information resonances (i.e., increased information transfer for specific ranges of input frequencies). The resonances are created at the expense of decreased information transfer in other frequency ranges. Using linear response theory for stochastically firing neurons, we explain how feedback signals shape the neural transfer function for a single neuron as a function of network size. We also find that balanced excitatory and inhibitory feedback can further enhance information tuning while maintaining a constant mean firing rate. Finally, we apply this theory to in vivo experimental data from weakly electric fish in which the feedback loop can be opened. We show that it qualitatively predicts the observed effects of inhibitory feedback. Our study of feedback excitation and inhibition reveals a possible mechanism by which optimal processing may be achieved over selected frequency ranges. PMID:16383655

  9. A Comparative Survey Based on Processing Network Traffic Data Using Hadoop Pig and Typical Mapreduce

    Directory of Open Access Journals (Sweden)

    Anjali P P

    2014-02-01

    Full Text Available Big data analysis has now become an integral part of many computational and statistical departments. Analysis of peta-byte scale of data is having an enhanced importance in the present day scenario. Big data manipulation is now considered as a key area of research in the field of data analytics and novel techniques are being evolved day by day. Thousands of transaction requests are being processed in every minute by different websites related to e-commerce, shopping carts and online banking. Here comes the need of network traffic and weblog analysis for which Hadoop comes as a suggested solution. It can efficiently process the Netflow data collected from routers, switches or even from website access logs at fixed intervals.

  10. Investigating the Role of Biogeochemical Processes in the Northern High Latitudes on Global Climate Feedbacks Using an Efficient Scalable Earth System Model

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Atul K. [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2016-09-14

    The overall objectives of this DOE funded project is to combine scientific and computational challenges in climate modeling by expanding our understanding of the biogeophysical-biogeochemical processes and their interactions in the northern high latitudes (NHLs) using an earth system modeling (ESM) approach, and by adopting an adaptive parallel runtime system in an ESM to achieve efficient and scalable climate simulations through improved load balancing algorithms.

  11. Online feedback op schriftelijk werk: betere feedback in minder tijd.

    NARCIS (Netherlands)

    van den Berg, B.A.M.|info:eu-repo/dai/nl/288125797; van der Hulst, M.E.

    2015-01-01

    Feedback is a powerful teaching technic to raise students’ performance, provided that the feedback is informative on how to improve, is given in a timely manner and students have the opportunity to act upon it. Therefore, many institutions want their students to receive feedback on their performance

  12. Online feedback op schriftelijk werk: betere feedback in minder tijd.

    NARCIS (Netherlands)

    van den Berg, B.A.M.; van der Hulst, M.E.

    2015-01-01

    Feedback is a powerful teaching technic to raise students’ performance, provided that the feedback is informative on how to improve, is given in a timely manner and students have the opportunity to act upon it. Therefore, many institutions want their students to receive feedback on their performance

  13. An invasive-native mammalian species replacement process captured by camera trap survey random encounter models

    OpenAIRE

    2016-01-01

    Camera traps are used to estimate densities or abundances using capture-recapture and, more recently, random encounter models (REMs). We deploy REMs to describe an invasive-native species replacement process, and to demonstrate their wider application beyond abundance estimation. The Irish hare Lepus timidus hibernicus is a high priority endemic of conservation concern. It is threatened by an expanding population of non-native, European hares L. europaeus, an invasive species of global import...

  14. Survey of Parallel Data Processing in Context with MapReduce

    Directory of Open Access Journals (Sweden)

    Madhavi Vaidya

    2011-09-01

    Full Text Available MapReduce is a parallel programming model and an associated implementation introduced by Google. In the programming model, a user specifies the computation by two functions, Map and Reduce. The underlying MapReduce library automatically parallelizes the computation, and handles complicated issues like data distribution, load balancing and fault tolerance. The original MapReduce implementation by Google, as well as its open-source counterpart, Hadoop, is aimed for parallelizing computing in large clusters of commodity machines.This paper gives an overview of MapReduce programming model and its applications. The author has described here the workflow of MapReduce process. Some important issues, like fault tolerance, are studied in more detail. Even the illustration of working of Map Reduce is given. The data locality issue in heterogeneous environments can noticeably reduce the Map Reduce performance. In this paper, the author has addressed the illustration of data across nodes in a way that each node has a balanced data processing load stored in a parallel manner. Given a data intensive application running on a Hadoop Map Reduce cluster, the auhor has exemplified how data placement is done in Hadoop architecture and the role of Map Reduce in the Hadoop Architecture. The amount of data stored in each node to achieve improved data-processing performance is explained here.

  15. A Survey on Cloud Computing Security Issues, Vendor Evaluation and Selection Process: World Future Society

    Directory of Open Access Journals (Sweden)

    Arun Sangwan

    2014-05-01

    Full Text Available Cloud computing is an emerging technology which could replace long-established IT systems. Cloud computing made big strides forward in 2013, and if a host of industry experts proves correct, it will make even bigger advances in 2014. As Forbes, CxoToday, GigaOM, and other news services that cover technology report, the experts forecast many more companies joining clouds or creating their own; new professional services emerging to manage the clouds and the data within them; and the clouds’ expansion transforming IT and work life in general trough out the world. Cloud computing makes it possible for an organizations’ IT to be more malleable, save costs and process information and data faster than with long-established IT. Cloud computing is the operating of programs and storage of data and files in an online network, not on physical disks and hardware’s. Cloud computing arises from the IT technicians desire to add another layer of separation in processing information. Cloud Vendor Evaluation & Selection offering leverages the database to accelerate the identification and screening of candidate vendors in four-step vendor evaluation and selection process.

  16. Regional feedbacks under changing climate and land-use conditions

    Directory of Open Access Journals (Sweden)

    L. Batlle Bayer

    2012-04-01

    Full Text Available Ecosystem responses to a changing climate and human-induced climate forcings (e.g. deforestation might amplify (positive feedback or dampen (negative feedback the initial climate response. Feedbacks may include the biogeochemical (e.g. carbon cycle and biogeophysical feedbacks (e.g. albedo and hydrological cycle. Here, we first review the most important feedbacks and put them into the context of a conceptual framework, including the major processes and interactions between terrestrial ecosystems and climate. We explore potential regional feedbacks in four hot spots with pronounced potential changes in land-use/management and local climate: sub-Saharan Africa (SSA, Europe, the Amazon Basin and South and Southeast Asia. For each region, the relevant human-induced climate forcings and feedbacks were identified based on published literature.

    When evapotranspiration is limited by a soil water deficit, heat waves in Europe are amplified (positive soil moisture-temperature feedback. Drought events in the Amazon lead to further rainfall reduction when water recycling processes are affected (positive soil moisture-precipitation feedback. In SSA, the adoption of irrigation in the commonly rainfed systems can modulate the negative soil moisture-temperature feedback. In contrast, future water shortage in South and Southeast Asia can turn the negative soil moisture-temperature feedback into a positive one.

    Further research including advanced modeling strategies is needed to isolate the dominant processes affecting the strength and sign of the feedbacks. In addition, the socio-economic dimension needs to be considered in the ecosystems-climate system to include the essential role of human decisions on land-use and land-cover change (LULCC. In this context, enhanced integration between Earth System (ES and Integrated Assessment (IA modeling communities is strongly recommended.

  17. Self-control of feedback during motor learning: accounting for the absolute amount of feedback using a yoked group with self-control over feedback.

    Science.gov (United States)

    Hansen, Steve; Pfeiffer, Jacob; Patterson, Jae Todd

    2011-01-01

    A traditional control group yoked to a group that self-controls their reception of feedback receives feedback in the same relative and absolute manner. This traditional control group typically does not learn the task as well as the self-control group. Although the groups are matched for the amount of feedback they receive, the information is provided on trials in which the individual may not request feedback if he or she were provided the opportunity. Similarly, individuals may not receive feedback on trials for which it would be a beneficial learning experience. Subsequently, the mismatch between the provision of feedback and the potential learning opportunity leads to a decrement in retention. The present study was designed to examine motor learning for a yoked group with the same absolute amount of feedback, but who could self-control when they received feedback. Increased mental processing of error detection and correction was expected for the participants in the yoked self-control group because of their choice to employ a limited resource in the form of a decreasing amount of feedback opportunities. Participants in the yoked with self-control group committed fewer errors than the self-control group in retention and the traditional yoked group in both the retention and time transfer blocks. The results suggest that the yoked with self-control group was able to produce efficient learning effects and can be a viable control group for further motor learning studies.

  18. Alcohol assessment and feedback by email for university students: main findings from a randomised controlled trial.

    Science.gov (United States)

    McCambridge, Jim; Bendtsen, Marcus; Karlsson, Nadine; White, Ian R; Nilsen, Per; Bendtsen, Preben

    2013-11-01

    Brief interventions can be efficacious in changing alcohol consumption and increasingly take advantage of the internet to reach high-risk populations such as students. To evaluate the effectiveness of a brief online intervention, controlling for the possible effects of the research process. A three-arm parallel groups design was used to explore the magnitude of the feedback and assessment component effects. The three groups were: alcohol assessment and feedback (group 1); alcohol assessment only without feedback (group 2); and no contact, and thus neither assessment nor feedback (group 3). Outcomes were evaluated after 3 months via an invitation to participate in a brief cross-sectional lifestyle survey. The study was undertaken in two universities randomising the email addresses of all 14 910 students (the AMADEUS-1 study, trial registration: ISRCTN28328154). Overall, 52% (n = 7809) of students completed follow-up, with small differences in attrition between the three groups. For each of the two primary outcomes, there was one statistically significant difference between groups, with group 1 having 3.7% fewer risky drinkers at follow-up than group 3 (P = 0.006) and group 2 scoring 0.16 points lower than group 3 on the three alcohol consumption questions from the Alcohol Use Disorders Identification Test (AUDIT-C) (P = 0.039). This study provides some evidence of population-level benefit attained through intervening with individual students.

  19. Univé customer survey: Pay-As-You-Drive (PAYD) insurance : Report PAYD-2. Feedback from Pay-As-You-Drive insurance, both outside and inside the car

    NARCIS (Netherlands)

    Lewis Evans, Ben; den Heijer, Anne; Dijksterhuis, Chris; de Waard, Dick; Brookhuis, Karel; Tucha, Oliver

    2013-01-01

    On the 10th of January 2013 over 3500 Univé clients were contacted and asked to fill in an online survey via Qualtrics, a survey website company licenced by the University of Groningen, about the future of car insurance at Univé. These customers could be classified under three main headings; car ins

  20. Univé customer survey: Pay-As-You-Drive (PAYD) insurance : Report PAYD-2. Feedback from Pay-As-You-Drive insurance, both outside and inside the car

    NARCIS (Netherlands)

    Lewis Evans, Ben; den Heijer, Anne; Dijksterhuis, Chris; de Waard, Dick; Brookhuis, Karel; Tucha, Oliver

    2013-01-01

    On the 10th of January 2013 over 3500 Univé clients were contacted and asked to fill in an online survey via Qualtrics, a survey website company licenced by the University of Groningen, about the future of car insurance at Univé. These customers could be classified under three main headings; car