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Immediate Feedback (immediate + feedback)
Selected AbstractsStability analysis of an adaptive packet access scheme for mobile communication systems with high propagation delaysINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 2 2003Giovanni Giambene Abstract In this paper, we investigate a packet access scheme that is able to support mixed traffics in the presence of high propagation delays. Referring to a Time-Code Division Multiple Access air interface, we propose a Medium Access Control (MAC) protocol based on a random access scheme. A successful attempt grants the use of a slot-code resource. This protocol is named Adaptive Time Code-Packet Reservation Multiple Access (ATC-PRMA), since the access parameters are changed, depending on the traffic load conditions, so as to fulfil Quality of Service requirements. Numerical examples are carried out for the Low Earth Orbit (LEO)- Mobile Satellite System (MSS) scenario, but all these considerations could be applied to High-Altitude Platform Stations (HAPSs) as well. In both cases, high propagation delays prevent an immediate feedback to users. An analytical approach is proposed to study the stability of our MAC scheme. Accordingly, we define a criterion for optimizing system performance. The predicted ATC-PRMA behaviour is supported by simulation results. Finally, we show the performance improvement of ATC-PRMA with respect to a MAC protocol not employing adaptive parameters. Copyright © 2003 John Wiley & Sons, Ltd. [source] Efficient integration of isochronous and data bursty traffics in low earth orbit-mobile satellite systems,INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 3 2002Alessandro Andreadis Abstract This paper focuses on the radio resource management in low earth orbit-mobile satellite systems (LEO-MSSs) based on a time division multiple access (TDMA) air interface. A novel demand,assignment medium access control (MAC) protocol, named DRAMA+ (dynamic resource assignment multiple access,enhanced version), is proposed, where voice and Web traffic sources obtain transmission slots through requests sent by means of a random access phase. The round-trip propagation delay (RTD) of LEO-MSSs prevents an immediate feedback for each transmission attempt. Therefore, the main concern of the DRAMA+ scheme is to realize an efficient access phase. All the transmission requests successfully received at the satellite are managed by an on board scheduler. We have shown that DRAMA+ outperforms other techniques appeared in the literature in terms of voice quality, transmission delays for bursty data traffics and resource utilization. Moreover, a performance analysis of an ideal version of the DRAMA+ scheme has permitted us to prove the potentialities of the proposed DRAMA+ technique. Stability issues have been addressed as well as the impact on the DRAMA+ performance of the LEO satellite constellation RTD value. Copyright © 2002 John Wiley & Sons, Ltd. [source] Learning to collaborate by collaborating: a face-to-face collaborative activity for measuring and learning basics about teamwork1JOURNAL OF COMPUTER ASSISTED LEARNING, Issue 2 2009C. Cortez Abstract In today's fast-changing business environment, teams have emerged as a requirement for business success. However, in schools and universities, students are usually not taught teamwork skills. In this paper, we introduce learning to collaborate by collaborating, a process that enables collaboration and teamwork skills to be taught and measured through face-to-face collaborative work and class-wide activities supported by wirelessly connected hand-held devices. Following a description of learning to collaborate by collaborating, we present an experimental study whose results demonstrate that participants in the process displayed improved teamwork performance. We conclude that it is possible to effectively teach collaboration skills through the use of immediate feedback provided by a supporting technology. [source] The effect of questioning on concept learning within a hypertext systemJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 1 2002P.A. Howard-Jones Abstract Two studies report upon the effect of asking learners to answer questions when learning in a hypertext environment, even when no immediate feedback is given to learners about the appropriateness of their responses. Such questions may be useful as a means to induce responses that can be used to monitor learning, but here the hypothesis was investigated that their inclusion would also improve learning directly. In the first study, 80 student teachers answered embedded multiple-choice questions that encouraged analysis of examples. Concept learning achieved using this environment was significantly reduced when compared with an environment requiring no such responses. In the second study, a cohort of 68 students were asked to summarise the information illustrated by the examples. Here, learning was significantly improved as compared with the no-response condition. [source] Teaching science problem solving: An overview of experimental workJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 4 2001R. Taconis The traditional approach to teaching science problem solving is having the students work individually on a large number of problems. This approach has long been overtaken by research suggesting and testing other methods, which are expected to be more effective. To get an overview of the characteristics of good and innovative problem-solving teaching strategies, we performed an analysis of a number of articles published between 1985 and 1995 in high-standard international journals, describing experimental research into the effectiveness of a wide variety of teaching strategies for science problem solving. To characterize the teaching strategies found, we used a model of the capacities needed for effective science problem solving, composed of a knowledge base and a skills base. The relations between the cognitive capacities required by the experimental or control treatments and those of the model were specified and used as independent variables. Other independent variables were learning conditions such as feedback and group work. As a dependent variable we used standardized learning effects. We identified 22 articles describing 40 experiments that met the standards we deemed necessary for a meta-analysis. These experiments were analyzed both with quantitative (correlational) methods and with a systematic qualitative method. A few of the independent variables were found to characterize effective strategies for teaching science problem solving. Effective treatments all gave attention to the structure and function (the schemata) of the knowledge base, whereas attention to knowledge of strategy and the practice of problem solving turned out to have little effect. As for learning conditions, both providing the learners with guidelines and criteria they can use in judging their own problem-solving process and products, and providing immediate feedback to them were found to be important prerequisites for the acquisition of problem-solving skills. Group work did not lead to positive effects unless combined with other variables, such as guidelines and feedback. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 442,468, 2001 [source] Computer-aided calibration for visual estimation of vegetation coverJOURNAL OF VEGETATION SCIENCE, Issue 6 2009Åsa Gallegos Torell Abstract Question: What precision and accuracy of visual cover estimations can be achieved after repeated calibration with images of vegetation in which the true cover is known, and what factors influence the results? Methods: Digital images were created, in which the true cover of vegetation was digitally calculated. Fifteen observers made repeated estimates with immediate feedback on the true cover. The effects on precision and accuracy through time were evaluated with repeated proficiency tests. In a field trial, cover estimates, before and after calibration, were compared with point frequency data. Results: Even a short time of calibration greatly improves precision and accuracy of the estimates, and can also reduce the influence of different backgrounds, aggregation patterns and experience. Experienced observers had a stronger tendency to underestimate the cover of narrow-leaved grasses before calibration. The field trial showed positive effects of computer-based calibration on precision, in that it led to considerably less between-observer variation for one of the two species groups. Conclusions: Computer-aided calibration of vegetation cover estimation is simple, self-explanatory and time-efficient, and might possibly reduce biases and drifts in estimate levels over time. Such calibration can also reduce between-observer variation in field estimates, at least for some species. However, the effects of calibration on estimations in the field must be further evaluated, especially for multilayered vegetation. [source] Fast measurement of intracardiac pressure differences with 2D breath-hold phase-contrast MRI,MAGNETIC RESONANCE IN MEDICINE, Issue 6 2003Richard B. Thompson Abstract Intracardiovascular blood pressure differences can be derived from velocity images acquired with phase-contrast (PC) MRI by evaluating the Navier-Stokes equations. Pressure differences within a slice of interest can be calculated using only the in-plane velocity components from that slice. This rapid exam is proposed as an alternative to the lengthy 3D velocity imaging exams. Despite their good spatial coverage, the 3D exams are prone to artifacts and errors from respiratory motion and insufficient temporal resolution, and are unattractive in the clinical setting due to their excessive scan times (>10 min of free breathing). The proposed single-slice approach requires only one or two breath-holds of acquisition time, and the velocity data can be processed for the calculation of pressure differences online with immediate feedback. The impact of reducing the pressure difference calculation to two dimensions is quantified by comparison with 3D data sets for the case of blood flow within the cardiac chambers. The calculated pressure differences are validated using high-fidelity pressure transducers both in a pulsatile flow phantom and in vivo in a dog model. There was excellent agreement between the transducer and PC-MRI results in all of the studies. Magn Reson Med 49:1056,1066, 2003. Published 2003 Wiley-Liss, Inc. [source] Electromechanical Behavior of Nanoscale Silver Coatings on PET FibersPLASMA PROCESSES AND POLYMERS, Issue 9 2008Martin Amberg Abstract Plasma-assisted deposition of silver films on PET mono- and multifilament fibers provides conductive fibers for wearable electronics. The nanoscale films were prepared in a continuously running low pressure plasma process using an ICM design for sputtering from a silver target combined with a prior RF cleaning step. The electrical resistance of the as-deposited layers was measured in situ enabling an immediate feedback of the electrical properties, the film quality, applied Ag mass, and film thickness. The deposited quantity of Ag mass on the PET fibers was investigated by ICP-OES and was correlated with the electrical resistance of the film. The metallized fibers showed excellent mechanical properties for wearable electronics as demonstrated by tensile properties measurement. [source] Annotation: Neurofeedback , train your brain to train behaviourTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 1 2007Hartmut Heinrich Background:, Neurofeedback (NF) is a form of behavioural training aimed at developing skills for self-regulation of brain activity. Within the past decade, several NF studies have been published that tend to overcome the methodological shortcomings of earlier studies. This annotation describes the methodical basis of NF and reviews the evidence base for its clinical efficacy and effectiveness in neuropsychiatric disorders. Methods:, In NF training, self-regulation of specific aspects of electrical brain activity is acquired by means of immediate feedback and positive reinforcement. In frequency training, activity in different EEG frequency bands has to be decreased or increased. Training of slow cortical potentials (SCPs) addresses the regulation of cortical excitability. Results:, NF studies revealed paradigm-specific effects on, e.g., attention and memory processes and performance improvements in real-life conditions, in healthy subjects as well as in patients. In several studies it was shown that children with attention-deficit hyperactivity disorder (ADHD) improved behavioural and cognitive variables after frequency (e.g., theta/beta) training or SCP training. Neurophysiological effects could also be measured. However, specific and unspecific training effects could not be disentangled in these studies. For drug-resistant patients with epilepsy, significant and long-lasting decreases of seizure frequency and intensity through SCP training were documented in a series of studies. For other child psychiatric disorders (e.g., tic disorders, anxiety, and autism) only preliminary investigations are available. Conclusions:, There is growing evidence for NF as a valuable treatment module in neuropsychiatric disorders. Further, controlled studies are necessary to establish clinical efficacy and effectiveness and to learn more about the mechanisms underlying successful training. [source] Effectiveness of Increasing Emergency Department Patients' Self-perceived Risk for Being Human Immunodeficiency Virus (HIV) Infected Through Audio Computer Self-interview,based Feedback About Reported HIV Risk BehaviorsACADEMIC EMERGENCY MEDICINE, Issue 11 2009Roland C. Merchant MD Abstract Objectives:, Prior research has demonstrated that emergency department (ED) patient acceptance of human immunodeficiency virus (HIV) screening is partially dependent on patients' self-perceived risk of infection. The primary objective of this study was to determine the effectiveness of audio computer-assisted self-interview (ACASI)-based feedback. The intervention aimed to increase patient's self-perceived risk of being HIV infected by providing immediate feedback on their risk behaviors. Methods:, This 1-year, randomized, controlled trial at a U.S. ED enrolled a random sample of 18- to 64-year-old subcritically ill or injured adult patients who were not known to be HIV infected. All participants completed an anonymous, ACASI-based questionnaire about their HIV risk behaviors related to injection drug use and sex, as well as their self-perceived risk for being HIV infected. Participants were randomly assigned to one of two study groups: an intervention group in which participants received immediate ACASI-based feedback in response to each of their reported risk behaviors or a no-intervention group without feedback. Participants were asked to indicate their level of HIV risk on a five-point scale before and after they answered the questions. Change in level of self-perceived HIV risk was calculated and compared by study group using Pearson's chi-square test. An HIV risk behavior score that summarized reported HIV risk behavior was devised. Because HIV risk behaviors differ by sex, scores were calculated separately for each sex. Linear regression models that adjusted for study group and same subject covariance were employed to determine if higher HIV risk behavior scores were associated with an increase in self-perceived HIV risk. Results:, Of the 566 trial participants, the median age was 29 years (interquartile range [IQR] = 22,43 years), 62.2% were females, and 66.9% had been tested previously for HIV. After answering the reported HIV risk behavior questions, 12.6% of participants had an increase, 79.9% had no change, and 7.5% had a decrease in self-perceived HIV risk. Of the 46.6% of participants who initially indicated that they were not at risk for HIV, 11.4% had an increase in self-perceived HIV risk after answering the reported HIV risk behavior questions. Change in self-perceived HIV risk did not differ by study group (p = 0.77). There were no differences in reported HIV risk scores between the intervention and no-intervention groups for females (p = 0.78) or males (p = 0.86). In the linear regression models, a greater increase in self-perceived HIV risk was associated with higher reported HIV risk behavior scores for females (, = 0.59, 95% confidence interval [CI] = 0.15, 1.04) but not for males (, = 1.00, 95% CI = ,0.13 to 2.14). Conclusions:, Some ED patients can be moved, although modestly, to recognize their risk for being HIV infected by asking about their HIV risk behaviors. However, ACASI-based feedback messages about HIV risk behaviors do not increase subjects' self-perceived HIV risk. Female ED patients appear to increase their self-perceived HIV risk more than males when queried about their HIV risk behaviors. [source] "Sim Wars": A New Edge to Academic Residency CompetitionsACADEMIC EMERGENCY MEDICINE, Issue 2009Yasuharu Okuda Introduction: Simulation training is an educational modality that is increasingly being utilized by emergency medicine programs to train and assess residents in core competencies. During a recent national conference, patient simulators were used in a competition to highlight multitasking, teamwork, and patient care skills. The combination of audience participation and an expert panel provided a creative forum for learning. Methods: the Foundation for Education and Research in Neurological Emergencies (FERNE) and the Emergency Medicine Residents' Association (EMRA) sponsored an innovative competition between emergency medicine residencies during the 2008 Scientific Assembly of the American College of Emergency Physicians (ACEP). This competition used high-fidelity simulations to create scenarios on neurologic emergencies. Six teams were selected to participate in the three-hour single-elimination competition. The three-member resident teams were then randomly paired against another institution. Three separate 10 minute scenarios were created for the initial round, allowing paired teams to compete on the same scenario. An expert panel provided commentary and insight on the management by each team. In addition, the experts provided feedback in the areas of communication and team training. Each round's winners were determined by the audience using an interactive system. Results: Based on the immediate feedback from participants, audience members and the expert panelists, this event was an entertaining and successful learning experience for both residents and faculty. Like the Clinical Pathological Cases (CPC) competitions, "Sim Wars" provides a showcase for residencies to demonstrate practice philosophies while providing a unique emphasis on teamwork and communication skills. The ability to expand this program to include regional competitions that lead to a national contest could be the framework for future exciting and educational events. [source] Realisation of a fully-deterministic microlensing observing strategy for inferring planet populations,ASTRONOMISCHE NACHRICHTEN, Issue 7 2010M. Dominik Abstract Within less than 15 years, the count of known planets orbiting stars other than the Sun has risen from none to more than 400 with detections arising from four successfully applied techniques: Doppler-wobbles, planetary transits, gravitational microlensing, and direct imaging. While the hunt for twin Earths is on, a statistically well-defined sample of the population of planets in all their variety is required for probing models of planet formation and orbital evolution so that the origin of planets that harbour life, like and including ours, can be understood. Given the different characteristics of the detection techniques, a complete picture can only arise from a combination of their respective results. Microlensing observations are well-suited to reveal statistical properties of the population of planets orbiting stars in either the Galactic disk or bulge from microlensing observations, but a mandatory requirement is the adoption of strictly-deterministic criteria for selecting targets and identifying signals. Here, we describe a fully-deterministic strategy realised by means of the ARTEMiS (Automated Robotic Terrestrial Exoplanet Microlensing Search) system at the Danish 1.54-m telescope at ESO La Silla between June and August 2008 as part of the MiNDSTEp (Microlensing Network for the Detection of Small Terrestrial Exoplanets) campaign, making use of immediate feedback on suspected anomalies recognized by the SIGNALMEN anomaly detector. We demonstrate for the first time the feasibility of such an approach, and thereby the readiness for studying planet populations down to Earth mass and even below, with ground-based observations. While the quality of the real-time photometry is a crucial factor on the efficiency of the campaign, an impairment of the target selection by data of bad quality can be successfully avoided. With a smaller slew time, smaller dead time, and higher through-put, modern robotic telescopes could significantly outperform the 1.54-m Danish, whereas lucky-imaging cameras could set new standards for high-precision follow-up monitoring of microlensing events (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Deliberate Practice and Acquisition of Expert Performance: A General OverviewACADEMIC EMERGENCY MEDICINE, Issue 11 2008K. Anders Ericsson PhD Traditionally, professional expertise has been judged by length of experience, reputation, and perceived mastery of knowledge and skill. Unfortunately, recent research demonstrates only a weak relationship between these indicators of expertise and actual, observed performance. In fact, observed performance does not necessarily correlate with greater professional experience. Expert performance can, however, be traced to active engagement in deliberate practice (DP), where training (often designed and arranged by their teachers and coaches) is focused on improving particular tasks. DP also involves the provision of immediate feedback, time for problem-solving and evaluation, and opportunities for repeated performance to refine behavior. In this article, we draw upon the principles of DP established in other domains, such as chess, music, typing, and sports to provide insight into developing expert performance in medicine. [source] Cognitive and Social Issues in Emergency Medicine Knowledge Translation: A Research AgendaACADEMIC EMERGENCY MEDICINE, Issue 11 2007Jamie C. Brehaut PhD The individual practitioner is a linchpin in the process of translating new knowledge into practice, particularly in the emergency department, where physician autonomy is high, resources are limited, and decision-making situations are complex. An understanding of the cognitive and social processes that affect knowledge translation (KT) in emergency medicine (EM) is crucial and at present understudied. As part of the 2007 Academic Emergency Medicine Consensus Conference on KT in EM, our group sought to identify key research areas that would inform our understanding of these cognitive and social processes. We combined an online discussion group of interdisciplinary stakeholders, an extensive review of the existing literature, and a "public hearing" of the recommendations at the Consensus Conference to establish relative preference for the recommendations, as well as their relevance and clarity to attendees. We identified five key research areas as follows. 1) What provider-specific barriers/facilitators to the use of new knowledge are relevant in the EM setting? 2) Can social psychological theories of behavior change be used to develop better KT interventions for EM? 3) Can the study of "distributed cognition" suggest new vehicles for KT in the emergency department? 4) Can the concept of dual-process reasoning inform our understanding of the KT process? 5) Can patient-specific, immediate feedback serve as a vehicle for KT in EM? We believe that exploring these key research questions will directly lead to improved KT interventions and to further discussion of the cognitive and social factors impacting KT in EM. [source] Understanding the potential role of mobile phone-based monitoring on asthma self-management: qualitative studyCLINICAL & EXPERIMENTAL ALLERGY, Issue 5 2007H. Pinnock Summary Background National and international healthcare policy increasingly seeks technological solutions to the challenge of providing care for people with long-term conditions. Novel technologies, however, have the potential to change the dynamics of disease monitoring and self-management. We aimed to explore the opinions and concerns of people with asthma and primary care clinicians on the potential role of mobile phone monitoring technology (transmitting symptoms and peak flows, with immediate feedback of control and reminder of appropriate actions) in supporting asthma self-management. Methods This qualitative study recruited 48 participants (34 adults and teenagers with asthma, 14 asthma nurses and doctors) from primary care in Lothian (Central Scotland) and Kent (South East England). Thirty-nine participated in six focus groups, which included a demonstration of the technology; nine gave in-depth interviews before and after a 4-week trial of the technology. Results Participants considered that mobile phone-based monitoring systems can facilitate guided self-management although, paradoxically, may engender dependence on professional/technological support. In the early phases, as patients are learning to accept, understand and control their asthma, this support was seen as providing much-needed confidence. During the maintenance phase, when self-management predominates, patient and professionals were concerned that increased dependence may be unhelpful, although they appreciated that maintaining an on-going record could facilitate consultations. Conclusion Mobile phone-based monitoring systems have the potential to support guided self-management by aiding transition from clinician-supported early phases to effective self-management during the maintenance phase. Continuing development, adoption and formal evaluation of these systems should take account of the insights provided by our data. [source] | |||||||||||||