VIDEO BLOGGING AND ENGLISH PRESENTATION PERFORMANCE: A PILOT STUDY.
Alan Hung, Shao-Ting; Danny Huang, Heng-Tsung
2015-10-01
This study investigated the utility of video blogs in improving EFL students' performance in giving oral presentations and, further, examined the students' perceptions toward video blogging. Thirty-six English-major juniors participated in a semester-long video blog project for which they uploaded their 3-min. virtual presentation clips over 18 weeks. Their virtual presentation clips were rated by three raters using a scale for speaking performance that contained 14 presentation skills. Data sources included presentation clips, reflections, and interviews. The results indicated that the students' overall presentation performance improved significantly. In particular, among the 14 presentation skills projection, intonation, posture, introduction, conclusion, and purpose saw the most substantial improvement. Finally, the qualitative data revealed that learners perceived that the video blog project facilitated learning but increased anxiety.
Effect of computer game playing on baseline laparoscopic simulator skills.
Halvorsen, Fredrik H; Cvancarova, Milada; Fosse, Erik; Mjåland, Odd
2013-08-01
Studies examining the possible association between computer game playing and laparoscopic performance in general have yielded conflicting results and neither has a relationship between computer game playing and baseline performance on laparoscopic simulators been established. The aim of this study was to examine the possible association between previous and present computer game playing and baseline performance on a virtual reality laparoscopic performance in a sample of potential future medical students. The participating students completed a questionnaire covering the weekly amount and type of computer game playing activity during the previous year and 3 years ago. They then performed 2 repetitions of 2 tasks ("gallbladder dissection" and "traverse tube") on a virtual reality laparoscopic simulator. Performance on the simulator were then analyzed for association to their computer game experience. Local high school, Norway. Forty-eight students from 2 high school classes volunteered to participate in the study. No association between prior and present computer game playing and baseline performance was found. The results were similar both for prior and present action game playing and prior and present computer game playing in general. Our results indicate that prior and present computer game playing may not affect baseline performance in a virtual reality simulator.
Helbig-Lang, Sylvia; Poels, Vanja; Lincoln, Tania M
2016-11-01
Cognitive approaches to social anxiety suggest that an excessive brooding about one's performance in a social situation (post-event processing; PEP) is involved in the maintenance of anxiety. To date, most studies investigating PEP were conducted in laboratory settings. The present study sought to replicate previous findings on predictors of PEP after a naturalistic social performance situation. Sixty-five students, who had to give an evaluated presentation for credits, completed measures of trait social anxiety. Immediately after their presentation, participants rated state anxiety and attentional focus during the presentation, and provided an overall evaluation of their performance. One week after the presentation, they rated PEP during the preceding week, and reappraised their performance. Regression analyses demonstrated that the performance ratings after and self-focused attention during the presentation were unique predictors of PEP over and above the effects of trait and state anxiety. There was no evidence that PEP was associated with a biased recall of individual performance evaluations. The results support cognitive theories that emphasize the importance of negative self-perceptions in the development of social anxiety and related processes, and underline self-focused attention and self-evaluative processes as important targets during treatment.
Between-individual comparisons in performance evaluation: a perspective from prospect theory.
Wong, Kin Fai Ellick; Kwong, Jessica Y Y
2005-03-01
This article examines how between-individual comparisons influence performance evaluations in rating tasks. The authors demonstrated a systematic change in the perceived difference across ratees as a result of changing the way performance information is expressed. Study 1 found that perceived performance difference between 2 individuals was greater when their objective performance levels were presented with small numbers (e.g., absence rates of 2% vs. 5%) than when they were presented with large numbers (e.g., attendance rates of 98% vs. 95%). Extending this finding to situations involving trade-offs between multiple performance attributes across ratees, Study 2 showed that the relative preference for 1 ratee over another actually reversed when the presentation format of the performance information changed. The authors draw upon prospect theory to offer a theoretical framework describing the between-individual comparison aspect of performance evaluation.
Results of the 1979 NACUBO Comparative Performance Study and Investment Questionnaire.
ERIC Educational Resources Information Center
Dresner, Bruce M.
Results of the 1979 Comparative Performance Study of the National Association of College and Business Officers are presented. The study is designed to aid administrators in evaluating the performance of their investment pools. The report covers comparative performance information and related investment performance statistics and other endowment…
The Effect of Implied Performer Age and Group Membership on Evaluations of Music Performances
ERIC Educational Resources Information Center
Harrington, Ann M.
2018-01-01
This study examined the effects of implied performer age and group membership on listeners' evaluations of music performances. Undergraduate music majors (n = 23), nonmusic majors (n = 17), and members of a New Horizons ensemble (n = 16) were presented with six 30-second excerpts of concert band performances. Excerpts were presented to all…
PPP effectiveness study. [automatic procedures recording and crew performance monitoring system
NASA Technical Reports Server (NTRS)
Arbet, J. D.; Benbow, R. L.
1976-01-01
This design note presents a study of the Procedures and Performance Program (PPP) effectiveness. The intent of the study is to determine manpower time savings and the improvements in job performance gained through PPP automated techniques. The discussion presents a synopsis of PPP capabilities and identifies potential users and associated applications, PPP effectiveness, and PPP applications to other simulation/training facilities. Appendix A provides a detailed description of each PPP capability.
Tsai, Sang-Bing; Chien, Min-Fang; Xue, Youzhi; Li, Lei; Jiang, Xiaodong; Chen, Quan; Zhou, Jie; Wang, Lei
2015-01-01
The method by which high-technology product manufacturers balance profits and environmental performance is of crucial concern for governments and enterprises. To examine the environmental performance of manufacturers, the present study applied Fuzzy-DEMATEL model to examine environmental performance of the PCB industry in Taiwan. Fuzzy theory was employed to examine the environmental performance criteria of manufacturers and analyse fuzzy linguistics. The fuzzy-DEMATEL model was then employed to assess the direction and level of interaction between environmental performance criteria. The core environmental performance criteria which were critical for enhancing environmental performance of the PCB industry in Taiwan were identified and presented. The present study revealed that green design (a1), green material procurement (a2), and energy consumption (b3) constitute crucial reason criteria, the core criteria influencing other criteria, and the driving factors for resolving problems. PMID:26052710
Tsai, Sang-Bing; Chien, Min-Fang; Xue, Youzhi; Li, Lei; Jiang, Xiaodong; Chen, Quan; Zhou, Jie; Wang, Lei
2015-01-01
The method by which high-technology product manufacturers balance profits and environmental performance is of crucial concern for governments and enterprises. To examine the environmental performance of manufacturers, the present study applied Fuzzy-DEMATEL model to examine environmental performance of the PCB industry in Taiwan. Fuzzy theory was employed to examine the environmental performance criteria of manufacturers and analyse fuzzy linguistics. The fuzzy-DEMATEL model was then employed to assess the direction and level of interaction between environmental performance criteria. The core environmental performance criteria which were critical for enhancing environmental performance of the PCB industry in Taiwan were identified and presented. The present study revealed that green design (a1), green material procurement (a2), and energy consumption (b3) constitute crucial reason criteria, the core criteria influencing other criteria, and the driving factors for resolving problems.
The effect of presentation rate on foreign-language vocabulary learning.
Zeelenberg, René; de Jonge, Mario; Tabbers, Huib K; Pecher, Diane
2015-01-01
The present study examined the effect of presentation rate on foreign-language vocabulary learning. Experiment 1 varied presentation rates from 1 s to 16 s per pair while keeping the total study time per pair constant. Speakers of English studied Dutch-English translation pairs (e.g., kikker-frog) for 16 × 1 s, 8 × 2 s, 4 × 4 s, 2 × 8 s, or 1 × 16 s. The results showed a nonmonotonic relationship between presentation rate and recall performance for both translation directions (Dutch → English and English → Dutch). Performance was best for intermediate presentation rates and dropped off for short (1 s) or long (16 s) presentation rates. Experiment 2 showed that the nonmonotonic relationship between presentation rate and recall performance was still present after a 1-day retention interval for both translation directions. Our results suggest that a presentation rate in the order of 4 s results in optimal learning of foreign-language vocabulary.
Improving Job Performance: Workplace Learning Is the First Step
ERIC Educational Resources Information Center
Daryoush, Younes; Silong, Abu Daud; Omar, Zohara; Othman, Jamilah
2013-01-01
The present study aims to contribute new knowledge to the existing literature on workplace learning and job performance. Particularly, the study analyzes contemporary literature on workplace learning and job performance, specifically formal and informal learning as well as employee task performance and contextual performance. The study…
Creativity: Performativity's Poison or Its Antidote?
ERIC Educational Resources Information Center
Munday, Ian
2014-01-01
A common move in the study of creativity and performativity is to present the former as an antidote to the latter. Might we, therefore, see work on creativity in education as heralding an era of post-performativity? In this paper I argue that the portrayal of performativity in the literature on creativity presents an overly simplistic (vulgar?)…
Student laboratory presentations as a learning tool in anatomy education.
Chollet, Madeleine B; Teaford, Mark F; Garofalo, Evan M; DeLeon, Valerie B
2009-01-01
Previous studies have shown that anatomy students who complete oral laboratory presentations believe they understand the material better and retain it longer than they otherwise would if they only took examinations on the material; however, we have found no studies that empirically test such outcomes. The purpose of this study was to assess the effectiveness of oral presentations through comparisons with other methods of assessment, most notably, examination performance. Specifically, we tested whether students (n = 256) performed better on examination questions on topics covered by their oral presentations than on other topics. Each student completed two graded, 12-minute laboratory presentations on two different assigned topics during the course and took three examinations, each of which covered a third of the course material. Examination questions were characterized by type (memorization, pathway, analytical, spatial). A two-way repeated measures analysis of variance revealed that students performed better on topics covered by their presentations than on topics not covered by their presentations (P < 0.005), regardless of presentation grade (P > 0.05) and question type (P > 0.05). These results demonstrate empirically that oral presentations are an effective learning tool.
ERIC Educational Resources Information Center
Mo, Songtao
2011-01-01
The objective of this study is to investigate the association of intrinsic and extrinsic motivators and student performance. This study performs an exploratory analysis and presents evidence to demonstrate that intrinsic motivators affect the connection between external motivators and student performance. The empirical tests follow the framework…
Aging and solid shape recognition: Vision and haptics.
Norman, J Farley; Cheeseman, Jacob R; Adkins, Olivia C; Cox, Andrea G; Rogers, Connor E; Dowell, Catherine J; Baxter, Michael W; Norman, Hideko F; Reyes, Cecia M
2015-10-01
The ability of 114 younger and older adults to recognize naturally-shaped objects was evaluated in three experiments. The participants viewed or haptically explored six randomly-chosen bell peppers (Capsicum annuum) in a study session and were later required to judge whether each of twelve bell peppers was "old" (previously presented during the study session) or "new" (not presented during the study session). When recognition memory was tested immediately after study, the younger adults' (Experiment 1) performance for vision and haptics was identical when the individual study objects were presented once. Vision became superior to haptics, however, when the individual study objects were presented multiple times. When 10- and 20-min delays (Experiment 2) were inserted in between study and test sessions, no significant differences occurred between vision and haptics: recognition performance in both modalities was comparable. When the recognition performance of older adults was evaluated (Experiment 3), a negative effect of age was found for visual shape recognition (younger adults' overall recognition performance was 60% higher). There was no age effect, however, for haptic shape recognition. The results of the present experiments indicate that the visual recognition of natural object shape is different from haptic recognition in multiple ways: visual shape recognition can be superior to that of haptics and is affected by aging, while haptic shape recognition is less accurate and unaffected by aging. Copyright © 2015 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Tanaka, Ayumi; Takehara, Takuma; Yamauchi, Hirotsugu
2006-01-01
The aims of the study were to test the linkages between achievement goals to task performance, as mediated by state anxiety arousal. Performance expectancy was also examined as antecedents of achievement goals. A presentation task in a computer practice class was used as achievement task. Fifty-three undergraduates (37 females and 16 males) were…
Performance evaluation of the use of photovoltaics to power a street light in Lowell
NASA Astrophysics Data System (ADS)
Crowell, Adam B.
Commercial, off-grid photovoltaic (PV) lighting systems present an attractive alternative to traditional outdoor lighting at sites where grid power is unavailable or unreliable. This study presents a comprehensive theoretical site analysis for the installation of standalone PV lighting systems at the Lowell National Historic Park in Lowell, MA. Detailed insolation studies are performed at the target site, resulting in expected daily Watt-hour totals available for battery charging for each month of the year. Illumination simulations are presented, detailing the expected lighting performance of the systems at night. Light levels are compared to those dictated by accepted standards. While it is acknowledged that the target site presents significant challenges to photovoltaics, such as severe shading, final system component specifications are provided, along with programming and positioning recommendations that will yield the best achievable performance.
Performance Support Case Studies from IBM.
ERIC Educational Resources Information Center
Duke-Moran, Celia; Swope, Ginger; Morariu, Janis; deKam, Peter
1999-01-01
Presents two case studies that show how IBM addressed performance support solutions and electronic learning. The first developed a performance support and expert coaching solution; the second applied performance support to reducing implementation time and total cost of ownership of enterprise resource planning systems. (Author/LRW)
ERIC Educational Resources Information Center
Masui, Chris; Broeckmans, Jan; Doumen, Sarah; Groenen, Anne; Molenberghs, Geert
2014-01-01
Research has reported equivocal results regarding the relationship between study time investment and academic performance in higher education. In the setting of the active, assignment-based teaching approach at Hasselt University (Belgium), the present study aimed (a) to further clarify the role of study time in academic performance, while taking…
Results of the 1978 NACUBO Comparative Performance Study and Investment Questionnaire.
ERIC Educational Resources Information Center
Dresner, Bruce M.
Information from the 1978 Comparative Performance Study and investment questionnaire conducted by the National Association of College and University Business Officers is presented. One hundred forty-four institutions provided information about 164 investment pools. The Comparative Performance Study provides participating institutions with…
Emotional Intelligence of Instructors and the Quality of Their Instructional Performance
ERIC Educational Resources Information Center
Dev, Smitha; Nair, Sreethi; Dwivedi, Anand
2016-01-01
Quality of instructional performance is the key skill needed for every teaching faculty for achieving the level of pedigree in the present educational scenario. However, the truth is that there are minimal studies to analyze the competency linking emotional intelligence to quality of instructional performance. Therefore the present attempt is to…
NASA Technical Reports Server (NTRS)
Davidson, Frederic M.; Sun, Xiaoli; Field, Christopher T.
1994-01-01
Accomplishments in the following areas of research are presented: receiver performance study of spaceborne laser altimeters and cloud and aerosol lidars; receiver performance analysis for space-to-space laser ranging systems; and receiver performance study for the Mars Environmental Survey (MESUR).
The Human Performance Envelope: Past Research, Present Activities and Future Directions
NASA Technical Reports Server (NTRS)
Edwards, Tamsyn
2017-01-01
Air traffic controllers (ATCOs) must maintain a consistently high level of human performance in order to maintain flight safety and efficiency. In current control environments, performance-influencing factors such as workload, fatigue and situation awareness can co-occur, and interact, to effect performance. However, multifactor influences and the association with performance are under-researched. This study utilized a high fidelity human in the loop enroute air traffic control simulation to investigate the relationship between workload, situation awareness and ATCO performance. The study aimed to replicate and extend Edwards, Sharples, Wilson and Kirwans (2012) previous study and confirm multifactor interactions with a participant sample of ex-controllers. The study also aimed to extend Edwards et als previous research by comparing multifactor relationships across 4 automation conditions. Results suggest that workload and SA may interact to produce a cumulative impact on controller performance, although the effect of the interaction on performance may be dependent on the context and amount of automation present. Findings have implications for human-automation teaming in air traffic control, and the potential prediction and support of ATCO performance.
Predictors of Academic Performance among Indian Students
ERIC Educational Resources Information Center
Ganguly, Sohinee; Kulkarni, Mrinmoyi; Gupta, Meenakshi
2017-01-01
There are two dominant strains in the literature on academic performance, the attribution studies and the self-efficacy studies. The present study attempted to incorporate these two strains while examining the academic performance of engineering undergraduate students in India. Time management and perceived stress were included in the model to…
Engagement beyond Interruption: A Performative Perspective on Listening and Ethics
ERIC Educational Resources Information Center
McRae, Chris; Nainby, Keith
2015-01-01
This article presents an understanding of listening as a performative and pedagogical act. Moving beyond existing theories of listening in communication and education studies that frame listening as a selective and incremental act, this article considers listening in terms of a performance studies and critical education studies perspective. An…
Promising high monetary rewards for future task performance increases intermediate task performance.
Zedelius, Claire M; Veling, Harm; Bijleveld, Erik; Aarts, Henk
2012-01-01
In everyday life contexts and work settings, monetary rewards are often contingent on future performance. Based on research showing that the anticipation of rewards causes improved task performance through enhanced task preparation, the present study tested the hypothesis that the promise of monetary rewards for future performance would not only increase future performance, but also performance on an unrewarded intermediate task. Participants performed an auditory Simon task in which they responded to two consecutive tones. While participants could earn high vs. low monetary rewards for fast responses to every second tone, their responses to the first tone were not rewarded. Moreover, we compared performance under conditions in which reward information could prompt strategic performance adjustments (i.e., when reward information was presented for a relatively long duration) to conditions preventing strategic performance adjustments (i.e., when reward information was presented very briefly). Results showed that high (vs. low) rewards sped up both rewarded and intermediate, unrewarded responses, and the effect was independent of the duration of reward presentation. Moreover, long presentation led to a speed-accuracy trade-off for both rewarded and unrewarded tones, whereas short presentation sped up responses to rewarded and unrewarded tones without this trade-off. These results suggest that high rewards for future performance boost intermediate performance due to enhanced task preparation, and they do so regardless whether people respond to rewards in a strategic or non-strategic manner.
Promising High Monetary Rewards for Future Task Performance Increases Intermediate Task Performance
Zedelius, Claire M.; Veling, Harm; Bijleveld, Erik; Aarts, Henk
2012-01-01
In everyday life contexts and work settings, monetary rewards are often contingent on future performance. Based on research showing that the anticipation of rewards causes improved task performance through enhanced task preparation, the present study tested the hypothesis that the promise of monetary rewards for future performance would not only increase future performance, but also performance on an unrewarded intermediate task. Participants performed an auditory Simon task in which they responded to two consecutive tones. While participants could earn high vs. low monetary rewards for fast responses to every second tone, their responses to the first tone were not rewarded. Moreover, we compared performance under conditions in which reward information could prompt strategic performance adjustments (i.e., when reward information was presented for a relatively long duration) to conditions preventing strategic performance adjustments (i.e., when reward information was presented very briefly). Results showed that high (vs. low) rewards sped up both rewarded and intermediate, unrewarded responses, and the effect was independent of the duration of reward presentation. Moreover, long presentation led to a speed-accuracy trade-off for both rewarded and unrewarded tones, whereas short presentation sped up responses to rewarded and unrewarded tones without this trade-off. These results suggest that high rewards for future performance boost intermediate performance due to enhanced task preparation, and they do so regardless whether people respond to rewards in a strategic or non-strategic manner. PMID:22905145
Study of helicopterroll control effectiveness criteria
NASA Technical Reports Server (NTRS)
Heffley, Robert K.; Bourne, Simon M.; Curtiss, Howard C., Jr.; Hindson, William S.; Hess, Ronald A.
1986-01-01
A study of helicopter roll control effectiveness based on closed-loop task performance measurement and modeling is presented. Roll control critieria are based on task margin, the excess of vehicle task performance capability over the pilot's task performance demand. Appropriate helicopter roll axis dynamic models are defined for use with analytic models for task performance. Both near-earth and up-and-away large-amplitude maneuvering phases are considered. The results of in-flight and moving-base simulation measurements are presented to support the roll control effectiveness criteria offered. This Volume contains the theoretical analysis, simulation results and criteria development.
Smets, Karolien; Moors, Pieter; Reynvoet, Bert
2016-01-01
Performance in a non-symbolic comparison task in which participants are asked to indicate the larger numerosity of two dot arrays, is assumed to be supported by the Approximate Number System (ANS). This system allows participants to judge numerosity independently from other visual cues. Supporting this idea, previous studies indicated that numerosity can be processed when visual cues are controlled for. Consequently, distinct types of visual cue control are assumed to be interchangeable. However, a previous study showed that the type of visual cue control affected performance using a simultaneous presentation of the stimuli in numerosity comparison. In the current study, we explored whether the influence of the type of visual cue control on performance disappeared when sequentially presenting each stimulus in numerosity comparison. While the influence of the applied type of visual cue control was significantly more evident in the simultaneous condition, sequentially presenting the stimuli did not completely exclude the influence of distinct types of visual cue control. Altogether, these results indicate that the implicit assumption that it is possible to compare performances across studies with a differential visual cue control is unwarranted and that the influence of the type of visual cue control partly depends on the presentation format of the stimuli. PMID:26869967
Spatial resolution requirements for soft-copy reporting in digital radiography
NASA Astrophysics Data System (ADS)
Davies, Andrew G.; Cowen, Arnold R.; Fowler, Richard C.; Bury, Robert F.; Parkin, Geoff J. S.; Lintott, David J.; Martinez, Delia; Safudim, Asif
1996-04-01
The issue of the spatial resolution required in order to present diagnostic quality digital images, especially for softcopy reporting, has received much attention over recent years. The aim of this study was to compare the diagnostic performance reporting from hardcopy and optimized softcopy image presentations. One-hundred-fifteen radiographs of the hand acquired on a photostimulable phosphor computed radiography (CR) system were chosen as the image material. The study group was taken from patients who demonstrated subtle erosions of the bone in the digits. The control group consisted of radiologically normal bands. The images were presented in three modes, the CR system's hardcopy output, and softcopy presentations at full and half spatial resolutions. Four consultant radiologists participated as observers. Results were analyzed using the receiver operating characteristic (ROC) technique, and showed a statistically significant improvement in observer performance for both softcopy formats, when compared to the hardcopy presentation. However, no significant difference in observer performance was found between the two softcopy presentations. We therefore conclude that, with appropriate attention to the processing and presentation of digital image data, softcopy reporting can, for most examinations, provide superior diagnostic performance, even for images viewed at modest (1 k2) resolutions.
ERIC Educational Resources Information Center
Law, Wilbert; Elliot, Andrew J.; Murayama, Kou
2012-01-01
In the present research, we conducted 4 studies designed to examine the hypothesis that perceived competence moderates the relation between performance-approach and performance-avoidance goals. Each study yielded supportive data, indicating that the correlation between the 2 goals is lower when perceived competence is high. This pattern was…
ERIC Educational Resources Information Center
Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Oliva, Doretta; Smaldone, Angela; La Martire, Maria L.; Alberti, Gloria; Scigliuzzo, Francesca
2011-01-01
In a recent single-case study, we showed that a new verbal-instruction system, ensuring the automatic presentation of step instructions, was beneficial for promoting the task performance of a woman with multiple disabilities (including blindness). The present study was aimed at replicating and extending the aforementioned investigation with three…
Study of target and non-target interplay in spatial attention task.
Sweeti; Joshi, Deepak; Panigrahi, B K; Anand, Sneh; Santhosh, Jayasree
2018-02-01
Selective visual attention is the ability to selectively pay attention to the targets while inhibiting the distractors. This paper aims to study the targets and non-targets interplay in spatial attention task while subject attends to the target object present in one visual hemifield and ignores the distractor present in another visual hemifield. This paper performs the averaged evoked response potential (ERP) analysis and time-frequency analysis. ERP analysis agrees to the left hemisphere superiority over late potentials for the targets present in right visual hemifield. Time-frequency analysis performed suggests two parameters i.e. event-related spectral perturbation (ERSP) and inter-trial coherence (ITC). These parameters show the same properties for the target present in either of the visual hemifields but show the difference while comparing the activity corresponding to the targets and non-targets. In this way, this study helps to visualise the difference between targets present in the left and right visual hemifields and, also the targets and non-targets present in the left and right visual hemifields. These results could be utilised to monitor subjects' performance in brain-computer interface (BCI) and neurorehabilitation.
Kim, Hyungil; Gabbard, Joseph L; Anon, Alexandre Miranda; Misu, Teruhisa
2018-04-01
This article investigates the effects of visual warning presentation methods on human performance in augmented reality (AR) driving. An experimental user study was conducted in a parking lot where participants drove a test vehicle while braking for any cross traffic with assistance from AR visual warnings presented on a monoscopic and volumetric head-up display (HUD). Results showed that monoscopic displays can be as effective as volumetric displays for human performance in AR braking tasks. The experiment also demonstrated the benefits of conformal graphics, which are tightly integrated into the real world, such as their ability to guide drivers' attention and their positive consequences on driver behavior and performance. These findings suggest that conformal graphics presented via monoscopic HUDs can enhance driver performance by leveraging the effectiveness of monocular depth cues. The proposed approaches and methods can be used and further developed by future researchers and practitioners to better understand driver performance in AR as well as inform usability evaluation of future automotive AR applications.
Talker and lexical effects on audiovisual word recognition by adults with cochlear implants.
Kaiser, Adam R; Kirk, Karen Iler; Lachs, Lorin; Pisoni, David B
2003-04-01
The present study examined how postlingually deafened adults with cochlear implants combine visual information from lipreading with auditory cues in an open-set word recognition task. Adults with normal hearing served as a comparison group. Word recognition performance was assessed using lexically controlled word lists presented under auditory-only, visual-only, and combined audiovisual presentation formats. Effects of talker variability were studied by manipulating the number of talkers producing the stimulus tokens. Lexical competition was investigated using sets of lexically easy and lexically hard test words. To assess the degree of audiovisual integration, a measure of visual enhancement, R(a), was used to assess the gain in performance provided in the audiovisual presentation format relative to the maximum possible performance obtainable in the auditory-only format. Results showed that word recognition performance was highest for audiovisual presentation followed by auditory-only and then visual-only stimulus presentation. Performance was better for single-talker lists than for multiple-talker lists, particularly under the audiovisual presentation format. Word recognition performance was better for the lexically easy than for the lexically hard words regardless of presentation format. Visual enhancement scores were higher for single-talker conditions compared to multiple-talker conditions and tended to be somewhat better for lexically easy words than for lexically hard words. The pattern of results suggests that information from the auditory and visual modalities is used to access common, multimodal lexical representations in memory. The findings are discussed in terms of the complementary nature of auditory and visual sources of information that specify the same underlying gestures and articulatory events in speech.
Talker and Lexical Effects on Audiovisual Word Recognition by Adults With Cochlear Implants
Kaiser, Adam R.; Kirk, Karen Iler; Lachs, Lorin; Pisoni, David B.
2012-01-01
The present study examined how postlingually deafened adults with cochlear implants combine visual information from lipreading with auditory cues in an open-set word recognition task. Adults with normal hearing served as a comparison group. Word recognition performance was assessed using lexically controlled word lists presented under auditory-only, visual-only, and combined audiovisual presentation formats. Effects of talker variability were studied by manipulating the number of talkers producing the stimulus tokens. Lexical competition was investigated using sets of lexically easy and lexically hard test words. To assess the degree of audiovisual integration, a measure of visual enhancement, Ra, was used to assess the gain in performance provided in the audiovisual presentation format relative to the maximum possible performance obtainable in the auditory-only format. Results showed that word recognition performance was highest for audiovisual presentation followed by auditory-only and then visual-only stimulus presentation. Performance was better for single-talker lists than for multiple-talker lists, particularly under the audiovisual presentation format. Word recognition performance was better for the lexically easy than for the lexically hard words regardless of presentation format. Visual enhancement scores were higher for single-talker conditions compared to multiple-talker conditions and tended to be somewhat better for lexically easy words than for lexically hard words. The pattern of results suggests that information from the auditory and visual modalities is used to access common, multimodal lexical representations in memory. The findings are discussed in terms of the complementary nature of auditory and visual sources of information that specify the same underlying gestures and articulatory events in speech. PMID:14700380
Can tutoring improve performance on a reasoning task under deadline conditions?
Osman, Magda
2007-03-01
The present study examined the effectiveness of a tutoring technique that has been used to identify and address participants' misunderstandings in Wason's selection task. In particular, the study investigated whether the technique would lead to improvements in performance when the task was presented in a deadline format (a condition in which time restrictions are imposed). In Experiment 1, the effects of tutoring on performance were compared in free time (conditions in which no time restrictions are imposed) and deadline task formats. In Experiment 2, improvements in performance were studied in deadline task formats, in which the tutoring and test phases were separated by an interval of 1 day. The results suggested that tutoring improved performance on the selection task under deadline and in free time conditions. Additionally, the study showed that participants made errors because they had misinterpreted the task. With tutoring, they were able to modify their initial misunderstandings.
IPAC-Inlet Performance Analysis Code
NASA Technical Reports Server (NTRS)
Barnhart, Paul J.
1997-01-01
A series of analyses have been developed which permit the calculation of the performance of common inlet designs. The methods presented are useful for determining the inlet weight flows, total pressure recovery, and aerodynamic drag coefficients for given inlet geometric designs. Limited geometric input data is required to use this inlet performance prediction methodology. The analyses presented here may also be used to perform inlet preliminary design studies. The calculated inlet performance parameters may be used in subsequent engine cycle analyses or installed engine performance calculations for existing uninstalled engine data.
Role of Organizational Culture on the Performance Primary School Teachers
ERIC Educational Resources Information Center
Suharningsih; Murtedjo
2017-01-01
This study aims to identify and examine the role of organizational culture on teacher performance. In the present study examined the role of organizational culture with teacher performance. In accordance with the study design, namely the survey, the data collected in this research is quantitative data. The data is extracted and obtained through…
Hair as a Biomarker of Long Term Mercury Exposure in Brazilian Amazon: A Systematic Review
de Oliveira Lima, Marcelo
2018-01-01
Many studies have assessed mercury (Hg) exposure in the Amazonian population. This article performs a literature search of the studies that used hair as a biomarker of Hg exposure in the Brazilian Amazonian population. The search covered the period from 1996 to 2016 and included articles which matched the following criteria: (1) articles related to Hg exposure into Brazilian Amazon; (2) articles that used hair as a biomarker of Hg exposure; (3) articles that used analytical tools to measure the Hg content on hair and (4) articles that presented arithmetic mean and/or minimum and maximum values of Hg. 36 studies were selected. The findings show that most of the studies were performed along margins of important rivers, such as Negro, Tapajós and Madeira. All the population presented mean levels of Hg on hair above 6 µg g−1 and general population, adults, not determined and men presented levels of Hg on hair above 10 µg g−1. The results show that most of the studies were performed by Brazilian institutions/researchers and the majority was performed in the State of Pará. The present study identified that Amazonian population has long-term been exposed to Hg. In terms of future perspectives, this study suggests the implementation of a strategic plan for environmental health surveillance in the region in order to promote health and benefit Amazonian population. PMID:29534534
Pfabigan, Daniela M.; Zeiler, Michael; Lamm, Claus; Sailer, Uta
2014-01-01
Objective Electrophysiological studies on feedback processing typically use a wide range of feedback stimuli which might not always be comparable. The current study investigated whether two indicators of feedback processing – feedback-related negativity (FRN) and P3b – differ for feedback stimuli with explicit (facial expressions) or assigned valence information (symbols). In addition, we assessed whether presenting feedback in either a trial-by-trial or a block-wise fashion affected these ERPs. Methods EEG was recorded in three experiments while participants performed a time estimation task and received two different types of performance feedback. Results Only P3b amplitudes varied consistently in response to feedback type for both presentation types. Moreover, the blocked feedback type presentation yielded more distinct FRN peaks, higher effect sizes, and a significant relation between FRN amplitudes and behavioral task performance measures. Conclusion Both stimulus type and presentation mode may provoke systematic changes in feedback-related ERPs. The current findings point at important potential confounds that need to be controlled for when designing FRN or P3b studies. Significance Studies investigating P3b amplitudes using mixed types of stimuli have to be interpreted with caution. Furthermore, we suggest implementing a blocked presentation format when presenting different feedback types within the same experiment. PMID:24144779
Bari, Muhammad Waseem; Fanchen, Meng; Baloch, Muhammad Awais
2016-01-01
The objective of this study is to examine the direct and indirect effect of management practices (procedural justice, coordination approach, communication system, integration strategy, and coping programs) on merger and acquisition (M&A) performance in the Pakistan banking industry. Psychological contract (PC) acts as a mediator between Management practices and M&A performance. The Present study distributes a structured questionnaire to 700 bank employees of different management cadres. The useful response rate is 76 % (536 employees). It uses PLS-SEM technique for data analysis. (1) procedural justice is a key strategy which has highly significant direct and indirect effect on M&A performance; however integration strategy and the communication system have an only direct effect. (2) PC performs partial mediation at different levels between management practices and M&A financial and non-financial performance. This study provides an effective solution to solve the soft issues during and post-M&A process. This is one of the few studies which effectively integrate the five constructs into a single framework to study their effects on M&A performance. Limitations and future research directions are presented in the last section of the study.
Disfluent presentations lead to the creation of more false memories.
Sanchez, Christopher A; Naylor, Jamie S
2018-01-01
The creation of false memories within the Deese-Roediger-McDermott (DRM) paradigm has been shown to be sensitive to many factors such as task instructions, participant mood, or even presentation modality. However, do other simple perceptual differences also impact performance on the DRM and the creation of false memories? This study explores the potential impact of changes in perceptual disfluency on DRM performance. To test for a potential influence of disfluency on false memory creation, participants viewed lists under either perceptually disfluent conditions or not. Results indicated that disfluency did significantly impact performance in the DRM paradigm; more disfluent presentations significantly increased the recall and recognition of unpresented information, although they did not impact recall or recognition of presented information. Thus, although disfluency did impact performance, disfluency did not produce a positive benefit related to overall task performance. This finding instead suggests that more disfluent presentations can increase the likelihood that false memories are created, and provide little positive performance benefit.
Disfluent presentations lead to the creation of more false memories
Naylor, Jamie S.
2018-01-01
The creation of false memories within the Deese-Roediger-McDermott (DRM) paradigm has been shown to be sensitive to many factors such as task instructions, participant mood, or even presentation modality. However, do other simple perceptual differences also impact performance on the DRM and the creation of false memories? This study explores the potential impact of changes in perceptual disfluency on DRM performance. To test for a potential influence of disfluency on false memory creation, participants viewed lists under either perceptually disfluent conditions or not. Results indicated that disfluency did significantly impact performance in the DRM paradigm; more disfluent presentations significantly increased the recall and recognition of unpresented information, although they did not impact recall or recognition of presented information. Thus, although disfluency did impact performance, disfluency did not produce a positive benefit related to overall task performance. This finding instead suggests that more disfluent presentations can increase the likelihood that false memories are created, and provide little positive performance benefit. PMID:29370255
Berry, Christopher M; Zhao, Peng
2015-01-01
Predictive bias studies have generally suggested that cognitive ability test scores overpredict job performance of African Americans, meaning these tests are not predictively biased against African Americans. However, at least 2 issues call into question existing over-/underprediction evidence: (a) a bias identified by Aguinis, Culpepper, and Pierce (2010) in the intercept test typically used to assess over-/underprediction and (b) a focus on the level of observed validity instead of operational validity. The present study developed and utilized a method of assessing over-/underprediction that draws on the math of subgroup regression intercept differences, does not rely on the biased intercept test, allows for analysis at the level of operational validity, and can use meta-analytic estimates as input values. Therefore, existing meta-analytic estimates of key parameters, corrected for relevant statistical artifacts, were used to determine whether African American job performance remains overpredicted at the level of operational validity. African American job performance was typically overpredicted by cognitive ability tests across levels of job complexity and across conditions wherein African American and White regression slopes did and did not differ. Because the present study does not rely on the biased intercept test and because appropriate statistical artifact corrections were carried out, the present study's results are not affected by the 2 issues mentioned above. The present study represents strong evidence that cognitive ability tests generally overpredict job performance of African Americans. (c) 2015 APA, all rights reserved.
Improving Reading Performance through Hypnosis.
ERIC Educational Resources Information Center
Fillmer, H. Thompson; And Others
1981-01-01
Describes a study investigating the effects of group hypnosis on the reading performance of university students in a reading and writing center. Discusses study procedures and presents data on pretest scores and gains in vocabulary and comprehension scores. Concludes that regular use of self-hypnosis significantly improved performance. (DMM)
Li, Xianchun; Cheng, Xiaojun; Li, Jiaying; Pan, Yafeng; Hu, Yi; Ku, Yixuan
2015-01-01
Previous studies have shown enhanced memory performance resulting from extensive action video game playing. The mechanisms underlying the cognitive benefit were investigated in the current study. We presented two types of retro-cues, with variable intervals to memory array (Task 1) or test array (Task 2), during the retention interval in a change detection task. In Task 1, action video game players demonstrated steady performance while non-action video game players showed decreased performance as cues occurred later, indicating their performance difference increased as the cue-to-memory-array intervals became longer. In Task 2, both participant groups increased their performance at similar rates as cues presented later, implying the performance difference in two groups were irrespective of the test-array-to-cue intervals. These findings suggested that memory benefit from game plays is not attributable to the higher ability of overcoming interference from the test array, but to the interactions between the two processes of protection from decay and resistance from interference, or from alternative hypotheses. Implications for future studies were discussed. PMID:26136720
Li, Xianchun; Cheng, Xiaojun; Li, Jiaying; Pan, Yafeng; Hu, Yi; Ku, Yixuan
2015-01-01
Previous studies have shown enhanced memory performance resulting from extensive action video game playing. The mechanisms underlying the cognitive benefit were investigated in the current study. We presented two types of retro-cues, with variable intervals to memory array (Task 1) or test array (Task 2), during the retention interval in a change detection task. In Task 1, action video game players demonstrated steady performance while non-action video game players showed decreased performance as cues occurred later, indicating their performance difference increased as the cue-to-memory-array intervals became longer. In Task 2, both participant groups increased their performance at similar rates as cues presented later, implying the performance difference in two groups were irrespective of the test-array-to-cue intervals. These findings suggested that memory benefit from game plays is not attributable to the higher ability of overcoming interference from the test array, but to the interactions between the two processes of protection from decay and resistance from interference, or from alternative hypotheses. Implications for future studies were discussed.
Study on the application of the time-compressed speech in children.
Padilha, Fernanda Yasmin Odila Maestri Miguel; Pinheiro, Maria Madalena Canina
2017-11-09
To analyze the performance of children without alteration of central auditory processing in the Time-compressed Speech Test. This is a descriptive, observational, cross-sectional study. Study participants were 22 children aged 7-11 years without central auditory processing disorders. The following instruments were used to assess whether these children presented central auditory processing disorders: Scale of Auditory Behaviors, simplified evaluation of central auditory processing, and Dichotic Test of Digits (binaural integration stage). The Time-compressed Speech Test was applied to the children without auditory changes. The participants presented better performance in the list of monosyllabic words than in the list of disyllabic words, but with no statistically significant difference. No influence on test performance was observed with respect to order of presentation of the lists and the variables gender and ear. Regarding age, difference in performance was observed only in the list of disyllabic words. The mean score of children in the Time-compressed Speech Test was lower than that of adults reported in the national literature. Difference in test performance was observed only with respect to the age variable for the list of disyllabic words. No difference was observed in the order of presentation of the lists or in the type of stimulus.
TDRSS telecommunications study. Phase 1: Final report
NASA Technical Reports Server (NTRS)
Cahn, C. R.; Cnossen, R. S.
1974-01-01
A parametric analysis of the telecommunications support capability of the Tracking and Data Relay Satellite System (TDRSS) was performed. Emphasis was placed on maximizing support capability provided to the user while minimizing impact on the user spacecraft. This study evaluates the present TDRSS configuration as presented in the TDRSS Definition Phase Study Report, December 1973 to determine potential changes for improving the overall performance. In addition, it provides specifications of the user transponder equipment to be used in the TDRSS.
NASA Technical Reports Server (NTRS)
1975-01-01
Results are presented of preliminary trade-off studies of operational SEASAT systems. The trade-off studies were used as the basis for the estimation of costs and net benefits of the operational SEASAT system. Also presented are the preliminary results of simulation studies that were designed to lead to a measure of the impact of SEASAT data through the use of numerical weather forecast models.
Lunar base thermal management/power system analysis and design
NASA Technical Reports Server (NTRS)
Mcghee, Jerry R.
1992-01-01
A compilation of several lunar surface thermal management and power system studies completed under contract and IR&D is presented. The work includes analysis and preliminary design of all major components of an integrated thermal management system, including loads determination, active internal acquisition and transport equipment, external transport systems (active and passive), passive insulation, solar shielding, and a range of lunar surface radiator concepts. Several computer codes were utilized in support of this study, including RADSIM to calculate radiation exchange factors and view factors, RADIATOR (developed in-house) for heat rejection system sizing and performance analysis over a lunar day, SURPWER for power system sizing, and CRYSTORE for cryogenic system performance predictions. Although much of the work was performed in support of lunar rover studies, any or all of the results can be applied to a range of surface applications. Output data include thermal loads summaries, subsystem performance data, mass, and volume estimates (where applicable), integrated and worst-case lunar day radiator size/mass and effective sink temperatures for several concepts (shielded and unshielded), and external transport system performance estimates for both single and two-phase (heat pumped) transport loops. Several advanced radiator concepts are presented, along with brief assessments of possible system benefits and potential drawbacks. System point designs are presented for several cases, executed in support of the contract and IR&D studies, although the parametric nature of the analysis is stressed to illustrate applicability of the analysis procedure to a wide variety of lunar surface systems. The reference configuration(s) derived from the various studies will be presented along with supporting criteria. A preliminary design will also be presented for the reference basing scenario, including qualitative data regarding TPS concerns and issues.
Listeners' expectation of room acoustical parameters based on visual cues
NASA Astrophysics Data System (ADS)
Valente, Daniel L.
Despite many studies investigating auditory spatial impressions in rooms, few have addressed the impact of simultaneous visual cues on localization and the perception of spaciousness. The current research presents an immersive audio-visual study, in which participants are instructed to make spatial congruency and quantity judgments in dynamic cross-modal environments. The results of these psychophysical tests suggest the importance of consilient audio-visual presentation to the legibility of an auditory scene. Several studies have looked into audio-visual interaction in room perception in recent years, but these studies rely on static images, speech signals, or photographs alone to represent the visual scene. Building on these studies, the aim is to propose a testing method that uses monochromatic compositing (blue-screen technique) to position a studio recording of a musical performance in a number of virtual acoustical environments and ask subjects to assess these environments. In the first experiment of the study, video footage was taken from five rooms varying in physical size from a small studio to a small performance hall. Participants were asked to perceptually align two distinct acoustical parameters---early-to-late reverberant energy ratio and reverberation time---of two solo musical performances in five contrasting visual environments according to their expectations of how the room should sound given its visual appearance. In the second experiment in the study, video footage shot from four different listening positions within a general-purpose space was coupled with sounds derived from measured binaural impulse responses (IRs). The relationship between the presented image, sound, and virtual receiver position was examined. It was found that many visual cues caused different perceived events of the acoustic environment. This included the visual attributes of the space in which the performance was located as well as the visual attributes of the performer. The addressed visual makeup of the performer included: (1) an actual video of the performance, (2) a surrogate image of the performance, for example a loudspeaker's image reproducing the performance, (3) no visual image of the performance (empty room), or (4) a multi-source visual stimulus (actual video of the performance coupled with two images of loudspeakers positioned to the left and right of the performer). For this experiment, perceived auditory events of sound were measured in terms of two subjective spatial metrics: Listener Envelopment (LEV) and Apparent Source Width (ASW) These metrics were hypothesized to be dependent on the visual imagery of the presented performance. Data was also collected by participants matching direct and reverberant sound levels for the presented audio-visual scenes. In the final experiment, participants judged spatial expectations of an ensemble of musicians presented in the five physical spaces from Experiment 1. Supporting data was accumulated in two stages. First, participants were given an audio-visual matching test, in which they were instructed to align the auditory width of a performing ensemble to a varying set of audio and visual cues. In the second stage, a conjoint analysis design paradigm was explored to extrapolate the relative magnitude of explored audio-visual factors in affecting three assessed response criteria: Congruency (the perceived match-up of the auditory and visual cues in the assessed performance), ASW and LEV. Results show that both auditory and visual factors affect the collected responses, and that the two sensory modalities coincide in distinct interactions. This study reveals participant resiliency in the presence of forced auditory-visual mismatch: Participants are able to adjust the acoustic component of the cross-modal environment in a statistically similar way despite randomized starting values for the monitored parameters. Subjective results of the experiments are presented along with objective measurements for verification.
Depressive self-presentation: beyond self-handicapping.
Weary, G; Williams, J P
1990-05-01
An experiment was conducted to examine the notion that depressives' responses would reflect a protective self-presentation style (Hill, Weary, & Williams, 1986), the underlying goal of which would be the avoidance of future performance demands and potential losses in self-esteem. In this study, depressed and nondepressed Ss were asked to perform a relatively simple visual-motor task. Half of the depressed and half of the nondepressed Ss were told that if they were successful at the task, they would be asked to perform a 2nd, similar task. The remaining Ss were given no such expectation of future performance. We predicted and found that depressed compared with nondepressed Ss strategically failed at the task when presented with the possibility of future performance and further losses in esteem. Moreover, this strategic failure was associated with some costs; depressed-future performance expectancy Ss experienced more discomfort or negative affect as a result of their performance. The relationship between this depressive self-presentation and self-handicapping strategies is discussed.
Dietrich, Julia Felicitas; Nuerk, Hans-Christoph; Klein, Elise; Moeller, Korbinian; Huber, Stefan
2017-08-29
Previous research has proposed that the approximate number system (ANS) constitutes a building block for later mathematical abilities. Therefore, numerous studies investigated the relationship between ANS acuity and mathematical performance, but results are inconsistent. Properties of the experimental design have been discussed as a potential explanation of these inconsistencies. In the present study, we investigated the influence of set size and presentation duration on the association between non-symbolic magnitude comparison and math performance. Moreover, we focused on strategies reported as an explanation for these inconsistencies. In particular, we employed a non-symbolic magnitude comparison task and asked participants how they solved the task. We observed that set size was a significant moderator of the relationship between non-symbolic magnitude comparison and math performance, whereas presentation duration of the stimuli did not moderate this relationship. This supports the notion that specific design characteristics contribute to the inconsistent results. Moreover, participants reported different strategies including numerosity-based, visual, counting, calculation-based, and subitizing strategies. Frequencies of these strategies differed between different set sizes and presentation durations. However, we found no specific strategy, which alone predicted arithmetic performance, but when considering the frequency of all reported strategies, arithmetic performance could be predicted. Visual strategies made the largest contribution to this prediction. To conclude, the present findings suggest that different design characteristics contribute to the inconsistent findings regarding the relationship between non-symbolic magnitude comparison and mathematical performance by inducing different strategies and additional processes.
Some design considerations for solar-powered aircraft
NASA Technical Reports Server (NTRS)
Phillips, W. H.
1980-01-01
Performance and operating characteristics are presented for a solar powered aircraft intended to remain aloft for long periods. The critical technologies which limit the performance are identified. By using the techniques presented, the effects of variation in the system parameters are studied. Practical design consideration are discussed.
How brain asymmetry relates to performance – a large-scale dichotic listening study
Hirnstein, Marco; Hugdahl, Kenneth; Hausmann, Markus
2014-01-01
All major mental functions including language, spatial and emotional processing are lateralized but how strongly and to which hemisphere is subject to inter- and intraindividual variation. Relatively little, however, is known about how the degree and direction of lateralization affect how well the functions are carried out, i.e., how lateralization and task performance are related. The present study therefore examined the relationship between lateralization and performance in a dichotic listening task for which we had data available from 1839 participants. In this task, consonant-vowel syllables are presented simultaneously to the left and right ear, such that each ear receives a different syllable. When asked which of the two they heard best, participants typically report more syllables from the right ear, which is a marker of left-hemispheric speech dominance. We calculated the degree of lateralization (based on the difference between correct left and right ear reports) and correlated it with overall response accuracy (left plus right ear reports). In addition, we used reference models to control for statistical interdependency between left and right ear reports. The results revealed a u-shaped relationship between degree of lateralization and overall accuracy: the stronger the left or right ear advantage, the better the overall accuracy. This u-shaped asymmetry-performance relationship consistently emerged in males, females, right-/non-right-handers, and different age groups. Taken together, the present study demonstrates that performance on lateralized language functions depends on how strongly these functions are lateralized. The present study further stresses the importance of controlling for statistical interdependency when examining asymmetry-performance relationships in general. PMID:24427151
Modeling and comparative study of linear and nonlinear controllers for rotary inverted pendulum
NASA Astrophysics Data System (ADS)
Lima, Byron; Cajo, Ricardo; Huilcapi, Víctor; Agila, Wilton
2017-01-01
The rotary inverted pendulum (RIP) is a problem difficult to control, several studies have been conducted where different control techniques have been applied. Literature reports that, although problem is nonlinear, classical PID controllers presents appropriate performances when applied to the system. In this paper, a comparative study of the performances of linear and nonlinear PID structures is carried out. The control algorithms are evaluated in the RIP system, using indices of performance and power consumption, which allow the categorization of control strategies according to their performance. This article also presents the modeling system, which has been estimated some of the parameters involved in the RIP system, using computer-aided design tools (CAD) and experimental methods or techniques proposed by several authors attended. The results indicate a better performance of the nonlinear controller with an increase in the robustness and faster response than the linear controller.
The Relationship between Depression and College Academic Performance
ERIC Educational Resources Information Center
DeRoma, Virginia M.; Leach, John B.; Leverett, J. Patrick
2009-01-01
The current study examined the association between self-reported depressive symptomology and college academic performance. A significant, negative relationship was found between depression and academic performance. Furthermore, students presenting with moderate levels of depressive symptoms demonstrated lower performance within academic…
Reis, Joana; Portugal, Ana Maria; Fernandes, Luís; Afonso, Nuno; Pereira, Mariana; Sousa, Nuno; Dias, Nuno S.
2016-01-01
The present study tested the effects of an intensive and short alpha and theta neurofeedback (NF) protocol in working memory (WM) performance in a healthy elder population and explored the effects of a multimodal approach, by supplementing NF with cognitive tasks. Participants were allocated to four groups: NF (N = 9); neurofeedback supplemented with cognitive training (NFCT) (N = 8); cognitive training (CT) (N = 7) and sham neurofeedback (Sham-NF) (N = 6). The intervention consisted in 30-min sessions for 8 days. The NF group presented post intervention increases of alpha and theta relative power as well as performance in the matrix rotation task. In addition, a successful up training of frontal theta showed positive correlation with an improvement of post-training alpha and a better performance in the matrix rotation task. The results presented herein suggest that an intensive and short NF protocol enables elders to learn alpha and theta self-modulation and already presents moderate improvements in cognition and basal EEG. Also, CT group showed moderate performance gains on the cognitive tasks used during the training sessions but no clear improvements on neurophysiology and behavioral measurements were observed. This study represents a first attempt to study the effects of an intensive and short NF protocol in WM performance of elders. The evidence presented here suggests that an intensive and short NF intervention could be a valid alternative for introduction of older populations to NF methodologies. PMID:27458369
Effects of age, gender, and stimulus presentation period on visual short-term memory.
Kunimi, Mitsunobu
2016-01-01
This study focused on age-related changes in visual short-term memory using visual stimuli that did not allow verbal encoding. Experiment 1 examined the effects of age and the length of the stimulus presentation period on visual short-term memory function. Experiment 2 examined the effects of age, gender, and the length of the stimulus presentation period on visual short-term memory function. The worst memory performance and the largest performance difference between the age groups were observed in the shortest stimulus presentation period conditions. The performance difference between the age groups became smaller as the stimulus presentation period became longer; however, it did not completely disappear. Although gender did not have a significant effect on d' regardless of the presentation period in the young group, a significant gender-based difference was observed for stimulus presentation periods of 500 ms and 1,000 ms in the older group. This study indicates that the decline in visual short-term memory observed in the older group is due to the interaction of several factors.
Role of HPC in Advancing Computational Aeroelasticity
NASA Technical Reports Server (NTRS)
Guruswamy, Guru P.
2004-01-01
On behalf of the High Performance Computing and Modernization Program (HPCMP) and NASA Advanced Supercomputing Division (NAS) a study is conducted to assess the role of supercomputers on computational aeroelasticity of aerospace vehicles. The study is mostly based on the responses to a web based questionnaire that was designed to capture the nuances of high performance computational aeroelasticity, particularly on parallel computers. A procedure is presented to assign a fidelity-complexity index to each application. Case studies based on major applications using HPCMP resources are presented.
NASA Technical Reports Server (NTRS)
1979-01-01
Results of a study leading to the preliminary design of a five passenger hybrid vehicle utilizing two energy sources (electricity and gasoline/diesel fuel) to minimize petroleum usage on a fleet basis are presented. The study methodology is described. Vehicle characterizations, the mission description, characterization, and impact on potential sales, and the rationale for the selection of the reference internal combustion engine vehicle are presented. Conclusions and recommendations of the mission analysis and performance specification report are included.
NASA Technical Reports Server (NTRS)
1972-01-01
The tug design and performance data base for the economic analysis of space tug operation are presented. A compendium of the detailed design and performance information from the data base is developed. The design data are parametric across a range of reusable space tug sizes. The performance curves are generated for selected point designs of expendable orbit injection stages and reusable tugs. Data are presented in the form of graphs for various modes of operation.
ERIC Educational Resources Information Center
Skehan, Peter; Foster, Pauline
2012-01-01
This chapter will present a research synthesis of a series of studies, termed here the Ealing research. The studies use the same general framework to conceptualise tasks and task performance, enabling easier comparability. The different studies, although each is self-contained, build into a wider picture of task performance. The major point of…
Short-Term Effects of Midseason Coach Turnover on Team Performance in Soccer
ERIC Educational Resources Information Center
Balduck, Anne-Line; Buelens, Marc; Philippaerts, Renaat
2010-01-01
The present study addressed the issue of short-term performance effects of midseason coach turnover in soccer. The goal of this study was to examine this effect on subsequent short-term team performance. The purposes of this study were to (a) examine whether midseason coach turnover improved results in the short term, and (b) examine how team…
Probiotic supplementation in sports and physical exercise: Does it present any ergogenic effect?
Coqueiro, Audrey Yule; de Oliveira Garcia, Amanda Beatriz; Rogero, Marcelo Macedo; Tirapegui, Julio
2017-12-01
Probiotics are live microorganisms that promote health benefits to the host. Evidence indicates that some probiotic strains play an immunomodulatory role and reduce the incidence of respiratory and gastrointestinal infections in athletes and in physical activity practitioners. For this reason, probiotic supplementation could indirectly improve exercise performance. However, recent studies have observed direct ergogenic effects of probiotics, but the mechanisms of action are poorly elucidated. In this study, we aim to synthesize available knowledge on the effect of probiotics on physical exercise, identify the mechanisms of action by which probiotics could improve performance directly and indirectly, and verify whether probiotics have any ergogenic effect. The study was performed in the PubMed database in February 2017, without limitation as to the publication period. The keyword combinations used were: 'Probiotics' and 'Sports' ( n = 17 articles), 'Probiotics' and 'Exercise' ( n = 26 articles) and 'Probiotics' and 'Athletes' ( n = 11 articles). Of the 16 studies evaluated, only six applied performance tests, of which only two demonstrated that probiotic supplementation increases performance, but one of them was performed with mice. According to the studies evaluated, probiotic supplementation does not present ergogenic effect, however, considering the small number of studies, this subject should be better investigated.
Pfabigan, Daniela M; Zeiler, Michael; Lamm, Claus; Sailer, Uta
2014-04-01
Electrophysiological studies on feedback processing typically use a wide range of feedback stimuli which might not always be comparable. The current study investigated whether two indicators of feedback processing - feedback-related negativity (FRN) and P3b - differ for feedback stimuli with explicit (facial expressions) or assigned valence information (symbols). In addition, we assessed whether presenting feedback in either a trial-by-trial or a block-wise fashion affected these ERPs. EEG was recorded in three experiments while participants performed a time estimation task and received two different types of performance feedback. Only P3b amplitudes varied consistently in response to feedback type for both presentation types. Moreover, the blocked feedback type presentation yielded more distinct FRN peaks, higher effect sizes, and a significant relation between FRN amplitudes and behavioral task performance measures. Both stimulus type and presentation mode may provoke systematic changes in feedback-related ERPs. The current findings point at important potential confounds that need to be controlled for when designing FRN or P3b studies. Studies investigating P3b amplitudes using mixed types of stimuli have to be interpreted with caution. Furthermore, we suggest implementing a blocked presentation format when presenting different feedback types within the same experiment. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Analysis of thermal performance of penetrated multi-layer insulation
NASA Technical Reports Server (NTRS)
Foster, Winfred A., Jr.; Jenkins, Rhonald M.; Yoo, Chai H.; Barrett, William E.
1988-01-01
Results of research performed for the purpose of studying the sensitivity of multi-layer insulation blanket performance caused by penetrations through the blanket are presented. The work described in this paper presents the experimental data obtained from thermal vacuum tests of various penetration geometries similar to those present on the Hubble Space Telescope. The data obtained from these tests is presented in terms of electrical power required sensitivity factors referenced to a multi-layer blanket without a penetration. The results of these experiments indicate that a significant increase in electrical power is required to overcome the radiation heat losses in the vicinity of the penetrations.
Design and performance of an analysis-by-synthesis class of predictive speech coders
NASA Technical Reports Server (NTRS)
Rose, Richard C.; Barnwell, Thomas P., III
1990-01-01
The performance of a broad class of analysis-by-synthesis linear predictive speech coders is quantified experimentally. The class of coders includes a number of well-known techniques as well as a very large number of speech coders which have not been named or studied. A general formulation for deriving the parametric representation used in all of the coders in the class is presented. A new coder, named the self-excited vocoder, is discussed because of its good performance with low complexity, and because of the insight this coder gives to analysis-by-synthesis coders in general. The results of a study comparing the performances of different members of this class are presented. The study takes the form of a series of formal subjective and objective speech quality tests performed on selected coders. The results of this study lead to some interesting and important observations concerning the controlling parameters for analysis-by-synthesis speech coders.
NASA Technical Reports Server (NTRS)
1989-01-01
Requirements are presented for shuttle system definition; performance and design characteristics; shuttle vehicle end item performance and design characteristics; ground operations complex performance and design characteristics; operability and system design and construction standards; and quality control.
Priming Ability-Relevant Social Categories Improves Intellectual Test Performance
ERIC Educational Resources Information Center
Lin, Phoebe S.; Kennette, Lynne N.; Van Havermaet, Lisa R.; Frank, Nichole M.; McIntyre, Rusty B.
2012-01-01
Research shows that priming affects behavioral tasks; fewer studies, however, have been conducted on how social category primes affect cognitive tasks. The present study aimed to examine the effects of social category primes on math performance and word recall. It was hypothesized that Asian prime words would improve math performance and word…
Development and Initial Validation of the Performance Perfectionism Scale for Sport (PPS-S)
ERIC Educational Resources Information Center
Hill, Andrew P.; Appleton, Paul R.; Mallinson, Sarah H.
2016-01-01
Valid and reliable instruments are required to appropriately study perfectionism. With this in mind, three studies are presented that describe the development and initial validation of a new instrument designed to measure multidimensional performance perfectionism for use in sport (Performance Perfectionism Scale--Sport [PPS-S]). The instrument is…
Summary Results of the 1980 NACUBO Comparative Performance Study and Investment Questionnaire.
ERIC Educational Resources Information Center
National Association of College and University Business Officers, Washington, DC.
This summary report contains information on the investments of college and university funds. It is the tenth annual study in the series by the National Association of College and University Business Officers (NACUBO). Sections present data and brief analysis on investment performance and endowment characteristics. Under investment performance,…
Impact of a Web-Based Adaptive Supplemental Digital Resource on Student Mathematics Performance
ERIC Educational Resources Information Center
Sharp, Laurie A.; Hamil, Marc
2018-01-01
Much literature has presented evidence that supplemental digital resources enhance student performance with mathematics. The purpose of this study was to explore the impact of a web-adaptive digital resource, Think Through Math©, on student performance with state-mandated annual standardized mathematics assessments. This study utilized a…
Impact of Metacognitive Awareness on Performance of Students in Chemistry
ERIC Educational Resources Information Center
Rahman, Fazal ur; Jumani, Nabi Bux; Chaudry, Muhammad Ajmal; Chisti, Saeed ul Hasan; Abbasi, Fahim
2010-01-01
The impact of metacognitive awareness on students' performance has been examined in the present study. 900 students of grade X participated in the study. Metacognitive awareness was measured using inventory, while performance of students was measured with the help of researcher made test in the subject of chemistry. Results indicated that…
Marijuana and actual driving performance
DOT National Transportation Integrated Search
1993-11-01
This report concerns the effects of marijuana smoking on actual driving performance. It presents the results of one pilot and three actual driving studies. The pilot study's major purpose was to establish the THC dose current marijuana users smoke to...
Suhr, Julie A; Berry, David T R
2017-12-01
Invalid self-report and invalid performance occur with high base rates in attention deficit/hyperactivity disorder (ADHD; Harrison, 2006; Musso & Gouvier, 2014). Although much research has focused on the development and validation of symptom validity tests (SVTs) and performance validity tests (PVTs) for psychiatric and neurological presentations, less attention has been given to the use of SVTs and PVTs in ADHD evaluation. This introduction to the special section describes a series of studies examining the use of SVTs and PVTs in adult ADHD evaluation. We present the series of studies in the context of prior research on noncredible presentation and call for future research using improved research methods and with a focus on assessment issues specific to ADHD evaluation. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
ERIC Educational Resources Information Center
Miranda, Monica Carolina; Sinnes, Elaine Girao; Pompeia, Sabine; Bueno, Orlando Francisco Amodeo
2008-01-01
Objective: The present study investigated the performance of Brazilian children in the Continuous Performance Test, CPT-II, and compared results to those of the norms obtained in the United States. Method: The U.S. norms were compared to those of a Brazilian sample composed of 6- to 11-year-olds separated into 4 age-groups (half boys) that…
Integrated flight/propulsion control system design based on a decentralized, hierarchical approach
NASA Technical Reports Server (NTRS)
Mattern, Duane; Garg, Sanjay; Bullard, Randy
1989-01-01
A sample integrated flight/propulsion control system design is presented for the piloted longitudinal landing task with a modern, statistically unstable fighter aircraft. The design procedure is summarized. The vehicle model used in the sample study is described, and the procedure for partitioning the integrated system is presented along with a description of the subsystems. The high-level airframe performance specifications and control design are presented and the control performance is evaluated. The generation of the low-level (engine) subsystem specifications from the airframe requirements are discussed, and the engine performance specifications are presented along with the subsystem control design. A compensator to accommodate the influence of airframe outputs on the engine subsystem is also considered. Finally, the entire closed loop system performance and stability characteristics are examined.
Integrated flight/propulsion control system design based on a decentralized, hierarchical approach
NASA Technical Reports Server (NTRS)
Mattern, Duane; Garg, Sanjay; Bullard, Randy
1989-01-01
A sample integrated flight/propulsion control system design is presented for the piloted longitiudinal landing task with a modern, statistically unstable fighter aircraft. The design procedure is summarized, the vehicle model used in the sample study is described, and the procedure for partitioning the integrated system is presented along with a description of the subsystems. The high-level airframe performance specifications and control design are presented and the control performance is evaluated. The generation of the low-level (engine) subsystem specifications from the airframe requirements are discussed, and the engine performance specifications are presented along with the subsystem control design. A compensator to accommodate the influence of airframe outputs on the engine subsystem is also considered. Finally, the entire closed loop system performance and stability characteristics are examined.
Ahmad, Fahad N; Moscovitch, Morris; Hockley, William E
2017-04-01
Konkle, Brady, Alvarez and Oliva (Psychological Science, 21, 1551-1556, 2010) showed that participants have an exceptional long-term memory (LTM) for photographs of scenes. We examined to what extent participants' exceptional LTM for scenes is determined by presentation time during encoding. In addition, at retrieval, we varied the nature of the lures in a forced-choice recognition task so that they resembled the target in gist (i.e., global or categorical) information, but were distinct in verbatim information (e.g., an "old" beach scene and a similar "new" beach scene; exemplar condition) or vice versa (e.g., a beach scene and a new scene from a novel category; novel condition). In Experiment 1, half of the list of scenes was presented for 1 s, whereas the other half was presented for 4 s. We found lower performance for shorter study presentation time in the exemplar test condition and similar performance for both study presentation times in the novel test condition. In Experiment 2, participants showed similar performance in an exemplar test for which the lure was of a different category but a category that was used at study. In Experiment 3, when presentation time was lowered to 500 ms, recognition accuracy was reduced in both novel and exemplar test conditions. A less detailed memorial representation of the studied scene containing more gist (i.e., meaning) than verbatim (i.e., surface or perceptual details) information is retrieved from LTM after a short compared to a long study presentation time. We conclude that our findings support fuzzy-trace theory.
Goo, Young-Mi; Kim, Tae-Ho; Lim, Jin-Yong
2016-03-01
[Purpose] The purpose of the present study is to examine the effects of abductor hallucis and gluteus maximus strengthening exercises on pronated feet. [Subjects and Methods] The present study was conducted with 18 adults without no history of surgery on the foot or ankle. One group performed both gluteus maximus strengthening exercises and abductor hallucis strengthening exercises, while the other group performed only abductor hallucis strengthening exercises five times per week for four weeks. [Results] The group that performed both gluteus maximus and abductor hallucis strengthening exercises showed smaller values in the height of navicular drop than the group that performed only abductor hallucis strengthening exercises. The muscle activity of the gluteus maximus and the vastus medialis increased during heel-strike in the group that added gluteus maximus exercises, and the muscle activity of the abductor hallucis significantly increased in both groups. [Conclusion] Given the results of the present study, it can be suggested that strengthening the gluteus maximus while also performing exercises to correct the pronated foot is an effective method for achieving normal gait.
Jongsma, Marijtje L A; Gerrits, Niels J H M; van Rijn, Clementina M; Quiroga, Rodrigo Quian; Maes, Joseph H R
2012-07-01
The aim of this study was to track recall performance and event-related potentials (ERPs) across multiple trials in a digit-learning task. When a sequence is practiced by repetition, the number of errors typically decreases and a learning curve emerges. Until now, almost all ERP learning and memory research has focused on effects after a single presentation and, therefore, fails to capture the dynamic changes that characterize a learning process. However, the current study used a free-recall task in which a sequence of ten auditory digits was presented repeatedly. Auditory sequences of ten digits were presented in a logical order (control sequences) or in a random order (experimental sequences). Each sequence was presented six times. Participants had to reproduce the sequence after each presentation. EEG recordings were made at the time of the digit presentations. Recall performance for the control sequences was close to asymptote right after the first learning trial, whereas performance for the experimental sequences initially displayed primacy and recency effects. However, these latter effects gradually disappeared over the six repetitions, resulting in near-asymptotic recall performance for all digits. The performance improvement for the middle items of the list was accompanied by an increase in P300 amplitude, implying a close correspondence between this ERP component and the behavioral data. These results, which were discussed in the framework of theories on the functional significance of the P300 amplitude, add to the scarce empirical data on the dynamics of ERP responses in the process of intentional learning. Copyright © 2011 Elsevier B.V. All rights reserved.
Influence of Personality and Motivation on Oral Presentation Performance.
Liang, Hsin-Yi; Kelsen, Brent
2018-01-19
Personality and motivation have been identified as influential variables associated with foreign language learning; however, few studies have investigated their effect on oral presentations. This study addresses the importance of both personality and motivation in students' collaborative oral presentation performance. A Big Five personality trait questionnaire measuring Extraversion, Agreeableness, Conscientiousness, Neuroticism and Openness to Experience, together with the Collaborative Inquiry-based Project Questionnaire measuring Task, Project Work, Reinforcement, Social Learning and Social Pressure motivational constructs were employed to evaluate 257 university students. In general, the results showed that Extraversion, Project Work and Social Pressure were significant correlates of oral presentation scores. The first result suggests that extraverts possess superiority in situations where oral language production is central to communication. This was particularly true for lower-level students, inferring that extraverted personalities can compensate for a lower English language ability. The second indicates that the inquiry-based nature of the assignments was an intrinsic motivator especially valued by extraverts. The third implies that extrinsic motivation was a factor influencing student performance. These findings extend previous research by highlighting the contextual relationships between these affective variables and performance in collaborative oral presentation contexts.
Kurtzman, Ellen T; Greene, Jessica
2016-01-01
This systematic review synthesizes what is known about the effective presentation of health care performance information for consumer decision making. Six databases were searched for articles published in English between September 2003 and April 2014. Experimental studies comparing consumers' responses to performance information when one or more presentation feature was altered were included. A thematic analysis was performed and practical guidelines derived. All 31 articles retained, the majority which tested responses to various presentations of health care cost and/or quality information, found that consumers better understand and make more informed choices when the information display is less complex. Simplification can be achieved by reducing the quantity of choices, displaying results in a positive direction, using non-technical language and evaluative elements, and situating results in common contexts. While findings do not offer a prescriptive design, this synthesis informs approaches to enhancing the presentation of health care performance information and areas that merit additional research. Guidelines derived from these results can be used to enhance health care performance reports for consumer decision making including using recognizable, evaluative graphics and customizable formats, limiting the amount of information presented, and testing presentation formats prior to use. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Stoeber, Joachim; Uphill, Mark A; Hotham, Sarah
2009-04-01
The question of how perfectionism affects performance is highly debated. Because empirical studies examining perfectionism and competitive sport performance are missing, the present research investigated how perfectionism affected race performance and what role athletes' goals played in this relationship in two prospective studies with competitive triathletes (Study 1: N = 112; Study 2: N = 321). Regression analyses showed that perfectionistic personal standards, high performance-approach goals, low performance-avoidance goals, and high personal goals predicted race performance beyond athletes' performance level. Moreover, the contrast between performance-avoidance and performance-approach goals mediated the relationship between perfectionistic personal standards and performance, whereas personal goal setting mediated the relationship between performance-approach goals and performance. The findings indicate that perfectionistic personal standards do not undermine competitive performance, but are associated with goals that help athletes achieve their best possible performance.
Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation
Goodman, Robert J.; Ryan, Richard M.; Anālayo, Bhikkhu
2016-01-01
Training in mindfulness, classically described as a receptive attentiveness to present events and experiences, has been shown to improve attention and working memory. Both are key to long-term memory formation, and the present three-study series used multiple methods to examine whether mindfulness would enhance episodic memory, a key form of long-term memory. In Study 1 (N = 143), a self-reported state of mindful attention predicted better recognition performance in the Remember-Know (R-K) paradigm. In Study 2 (N = 93), very brief training in a focused attention form of mindfulness also produced better recognition memory performance on the R-K task relative to a randomized, well-matched active control condition. Study 3 (N = 57) extended these findings by showing that relative to randomized active and inactive control conditions the effect of very brief mindfulness training generalized to free-recall memory performance. This study also found evidence for mediation of the mindfulness training—episodic memory relation by intrinsic motivation. These findings indicate that mindful attention can beneficially impact motivation and episodic memory, with potential implications for educational and occupational performance. PMID:27115491
Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation.
Brown, Kirk Warren; Goodman, Robert J; Ryan, Richard M; Anālayo, Bhikkhu
2016-01-01
Training in mindfulness, classically described as a receptive attentiveness to present events and experiences, has been shown to improve attention and working memory. Both are key to long-term memory formation, and the present three-study series used multiple methods to examine whether mindfulness would enhance episodic memory, a key form of long-term memory. In Study 1 (N = 143), a self-reported state of mindful attention predicted better recognition performance in the Remember-Know (R-K) paradigm. In Study 2 (N = 93), very brief training in a focused attention form of mindfulness also produced better recognition memory performance on the R-K task relative to a randomized, well-matched active control condition. Study 3 (N = 57) extended these findings by showing that relative to randomized active and inactive control conditions the effect of very brief mindfulness training generalized to free-recall memory performance. This study also found evidence for mediation of the mindfulness training-episodic memory relation by intrinsic motivation. These findings indicate that mindful attention can beneficially impact motivation and episodic memory, with potential implications for educational and occupational performance.
Children exhibit different performance patterns in explicit and implicit theory of mind tasks.
Oktay-Gür, Nese; Schulz, Alexandra; Rakoczy, Hannes
2018-04-01
Three studies tested scope and limits of children's implicit and explicit theory of mind. In Studies 1 and 2, three- to six-year-olds (N = 84) were presented with closely matched explicit false belief tasks that differed in whether or not they required an understanding of aspectuality. Results revealed that children performed equally well in the different tasks, and performance was strongly correlated. Study 3 tested two-year-olds (N = 81) in implicit interactive versions of these tasks and found evidence for dis-unity: children performed competently only in those tasks that did not require an understanding of aspectuality. Taken together, the present findings suggest that early implicit and later explicit theory of mind tasks may tap different forms of cognitive capacities. Copyright © 2018 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Cambridge Associates, Inc., Boston, MA.
This report presents the results of the 1995 study of the performance and management of college and university endowments, based on 394 institutions providing data. A summary abstract provides an overview of performance and investment data; and Part 1 of the study provides a brief commentary covering endowment characteristics, historical…
Studying Emotional Expression in Music Performance.
ERIC Educational Resources Information Center
Gabrielsson, Alf
1999-01-01
Explores the importance of emotional expression in music performance. Performers played music to express different emotions and then listening tests were conducted in order to determine whether the intended expressions were perceived. Presents and discusses the results. (CMK)
Detached Eddy Simulation of Flap Side-Edge Flow
NASA Technical Reports Server (NTRS)
Balakrishnan, Shankar K.; Shariff, Karim R.
2016-01-01
Detached Eddy Simulation (DES) of flap side-edge flow was performed with a wing and half-span flap configuration used in previous experimental and numerical studies. The focus of the study is the unsteady flow features responsible for the production of far-field noise. The simulation was performed at a Reynolds number (based on the main wing chord) of 3.7 million. Reynolds Averaged Navier-Stokes (RANS) simulations were performed as a precursor to the DES. The results of these precursor simulations match previous experimental and RANS results closely. Although the present DES simulations have not reached statistical stationary yet, some unsteady features of the developing flap side-edge flowfield are presented. In the final paper it is expected that statistically stationary results will be presented including comparisons of surface pressure spectra with experimental data.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Armstrong, Robert C.; Ray, Jaideep; Malony, A.
2003-11-01
We present a case study of performance measurement and modeling of a CCA (Common Component Architecture) component-based application in a high performance computing environment. We explore issues peculiar to component-based HPC applications and propose a performance measurement infrastructure for HPC based loosely on recent work done for Grid environments. A prototypical implementation of the infrastructure is used to collect data for a three components in a scientific application and construct performance models for two of them. Both computational and message-passing performance are addressed.
A Component Analysis of the Impact of Evaluative and Objective Feedback on Performance
ERIC Educational Resources Information Center
Johnson, Douglas A.
2013-01-01
Despite the frequency with which performance feedback interventions are used in organizational behavior management, component analyses of such feedback are rare. It has been suggested that evaluation of performance and objective details about performance are two necessary components for performance feedback. The present study was designed to help…
Sex Differences and the Factor of Time in Solving Vandenberg and Kuse Mental Rotation Problems
ERIC Educational Resources Information Center
Peters, M.
2005-01-01
In accounting for the well-established sex differences on mental rotation tasks that involve cube stimuli of the Shepard and Metzler (Shepard & Metzler, 1971) kind, performance factors are frequently invoked. Three studies are presented that examine performance factors. In Study 1, analyses of the performance of a large number of subjects…
Teachers' Performance Motivation System in Thai Primary Schools
ERIC Educational Resources Information Center
Pasathang, Sarojn; Tesaputa, Kowat; Sataphonwong, Pattananusron
2016-01-01
This research aims to: 1) study the present conditions and desirable condition of the motivation systems as well as how to find methods for motivating the performance of teachers in primary schools, 2) develop a motivation system for the performance of teachers in primary schools, 3) study the effects of using the motivation system for compliance…
ERIC Educational Resources Information Center
Wilcock, Rachel; Henry, Lucy
2013-01-01
Despite the large number of people with intellectual disabilities (ID) and the fact they are more likely to be victims and witnesses of crime, only two published studies have investigated their performance on identification line-up parades. In the present study we examined the identification performance of adults with and without ID on both a…
Effects of Chronotypes on Students' Choice, Participation, and Performance in Online Learning
ERIC Educational Resources Information Center
Luo, Yi; Pan, Rui; Choi, Jea H.; Strobel, Johannes
2018-01-01
Introducing a new theoretical framework of chronotypes (inner biological clock), this article presents a study examining students' choices, participation, and performance in two discussion-heavy online history courses. The study comprised two major parts: a repetition study and an exploratory study. The survey adopted in the repetition study…
NASA Technical Reports Server (NTRS)
Holmes, B. J.
1980-01-01
A design study has been conducted to optimize a single-engine airplane for a high-performance cruise mission. The mission analyzed included a cruise speed of about 300 knots, a cruise range of about 1300 nautical miles, and a six-passenger payload (5340 N (1200 lb)). The purpose of the study is to investigate the combinations of wing design, engine, and operating altitude required for the mission. The results show that these mission performance characteristics can be achieved with fuel efficiencies competitive with present-day high-performance, single- and twin-engine, business airplanes. It is noted that relaxation of the present Federal Aviation Regulation, Part 23, stall-speed requirement for single-engine airplanes facilitates the optimization of the airplane for fuel efficiency.
Study of a pursuit-evasion guidance law for high performance aircraft
NASA Technical Reports Server (NTRS)
Williams, Peggy S.; Menon, P. K. A.; Antoniewicz, Robert F.; Duke, Eugene L.
1989-01-01
The study of a one-on-one aircraft pursuit-evasion guidance scheme for high-performance aircraft is discussed. The research objective is to implement a guidance law derived earlier using differential game theory in conjunction with the theory of feedback linearization. Unlike earlier research in this area, the present formulation explicitly recognizes the two-sided nature of the pursuit-evasion scenario. The present research implements the guidance law in a realistic model of a modern high-performance fighter aircraft. Also discussed are the details of the guidance law, implementation in a highly detailed simulation of a high-performance fighter, and numerical results for two engagement geometries. Modifications of the guidance law for onboard implementation is also discussed.
Correlation tracking study for meter-class solar telescope on space shuttle. [solar granulation
NASA Technical Reports Server (NTRS)
Smithson, R. C.; Tarbell, T. D.
1977-01-01
The theory and expected performance level of correlation trackers used to control the pointing of a solar telescope in space using white light granulation as a target were studied. Three specific trackers were modeled and their performance levels predicted for telescopes of various apertures. The performance of the computer model trackers on computer enhanced granulation photographs was evaluated. Parametric equations for predicting tracker performance are presented.
Jones, Paul R.
2012-01-01
Introduction Two studies examined whether stereotype threat impairs women's math performance and whether concurrent threat reduction strategies can be used to offset this effect. Method In Study 1, collegiate men and women (N = 100) watched a video purporting that males and females performed equally well (gender-fair) or males outperformed females (gender differences) on an imminent math test. In Study 2, (N = 44) women viewed the gender differences video, followed by misattribution (cue present, absent) and self-affirmation (present, absent) manipulations, before taking the aforesaid test. Results In the initial study, women underperformed men on the test after receiving the gender differences video, whereas no gender differences emerged in the gender-fair condition. In Study 2, affirming the self led to better performance than not doing so. Planned contrasts indicated, however, that only women receiving a misattribution cue and self-affirmation opportunity outperformed their counterparts not given these reduction strategies. Discussion These findings are discussed relative to Stereotype Threat Theory and educational implications are provided. PMID:22545058
Liu, Chenxi; Tang, Yuqing; Wang, Dan; Zhang, Xinping
2017-06-01
Public reporting of comparative performance information (PRCPI) influence patients' decision making and optimal presentation of PRCPI is urgently required for successful patients' engagement and quality improvement. This study was to explore the presentation of PRCPI impacting on consumers' decision making.This research applied a controlled design, with participants allocated randomly to 6 groups, and a total of 515 participants were recruited in Yunnan province. Five aspects of PRCPI presentations were evaluated, including display (star rating vs numeric information), and whether information was simplified, interpreted, overload, or ranked. Participants were stimulated to identify the best or worst physicians with a hypothetical scenario. Main outcome measures were correct choices rate of best/worst physicians, indicating participants fully understood and correctly used PRCPI. χ test and logistic regression were applied to assess the effect between different presentations on consumers' decision making.The correct choices rate is only 48.93%. Compared with star rating, numerical information helped participants differentiate low-performance physicians (OR = 2.573, P = .029), including low-performance physicians in antibiotics (OR = 2.974, P = .031) and low-performance physicians in injections (OR = 2.369, P = .035). Disordered information impeded participants to fully understand and correctly use PRCPI (OR = 0.519, P = .041). The effect was mainly reflected on participants differentiating low-performance physicians (OR = 0.491, P = .039) and low-performance physicians in injections (OR = 0.440, P = .016). Other aspects of PRCPI showed nonsignificant impacts on consumers' decision making.Presentation, including information display and ranking, can influence patients' correct usage of PRCPI and the effect was mainly observed when the patients were identifying poorly performing physicians. The present study demonstrated that numerical and ranked PRCPI, combined with sufficient patient education, could be most effective to facilitate patient use.
Palermo, C; Volders, E; Gibson, S; Kennedy, M; Wray, A; Thomas, J; Hannan-Jones, M; Gallegos, D; Beck, E
2018-02-01
Assessment presents one of the greatest challenges to evaluating health professional trainee performance, as a result of the subjectivity of judgements and variability in assessor standards. The present study aimed to test a moderation procedure for assessment across four independent universities and explore approaches to assessment and the factors that influence assessment decisions. Assessment tasks designed independently by each of the four universities to assess student readiness for placement were chosen for the present study. Each university provided four student performance recordings for moderation. Eight different academic assessors viewed the student performances and assessed them using the corresponding university assessment instrument. Assessment results were collated and presented back to the assessors, together with the original university assessment results. Results were discussed with assessors to explore variations. The discussion was recorded, transcribed, thematically analysed and presented back to all assessors to achieve consensus on the emerging major learnings. Although there were differences in absolute scores, there was consistency (12 out of 16 performances) in overall judgement decisions regarding placement readiness. Proficient communication skills were considered a key factor when determining placement readiness. The discussion revealed: (i) assessment instruments; (ii) assessor factors; and (iii) the subjectivity of judgement as the major factors influencing assessment. Assessment moderation is a useful method for improving the quality of assessment decisions by sharing understanding and aligning standards of performance. © 2017 The British Dietetic Association Ltd.
Airport Surface Traffic Control Concept Formulation Study : Volume 4. Estimation of Requirements
DOT National Transportation Integrated Search
1975-07-01
A detailed study of requirements was performed and is presented. This requirements effort provided an estimate of the performance requirements of a surveillance sensor that would be required in a TAGS (Tower Automated Ground Surveillance) system for ...
DOT National Transportation Integrated Search
1974-02-01
The volume presents the results of the subsystem performance requirements study for an Advanced Air Traffic Management System (AATMS). The study determined surveillance and navigation subsystem requirements for terminal and enroute area operations. I...
Case Studies in Educational Performance Contracting. Part 1. Conclusions and Implications.
ERIC Educational Resources Information Center
Carpenter, Polly; Hall, George R.
This volume presents conclusions and implications derived from five cities' experience with performance contracting in education: Norfolk, Virginia; Texarkana, Arkansas (with Liberty-Eylau, Texas); Gary, Indiana, Gilroy, California; and Grand Rapids, Michigan. The five case studies cover eight programs in 15 schools. While each study is treated in…
Modeling synchronous voltage source converters in transmission system planning studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kosterev, D.N.
1997-04-01
A Voltage Source Converter (VSC) can be beneficial to power utilities in many ways. To evaluate the VSC performance in potential applications, the device has to be represented appropriately in planning studies. This paper addresses VSC modeling for EMTP, powerflow, and transient stability studies. First, the VSC operating principles are overviewed, and the device model for EMTP studies is presented. The ratings of VSC components are discussed, and the device operating characteristics are derived based on these ratings. A powerflow model is presented and various control modes are proposed. A detailed stability model is developed, and its step-by-step initialization proceduremore » is described. A simplified stability model is also derived under stated assumptions. Finally, validation studies are performed to demonstrate performance of developed stability models and to compare it with EMTP simulations.« less
Measurement of health system performance at district level: A study protocol
Sharma, Atul; Prinja, Shankar; Aggarwal, Arun Kumar
2018-01-01
Background Limited efforts have been observed in low and middle income countries to undertake health system performance assessment at district level. Absence of a comprehensive data collection tool and lack of a standardised single summary measure defining overall performance are some of the main problems. Present study has been undertaken to develop a summary composite health system performance index at district level. Methods A broad range of indicators covering all six domains as per building block framework were finalized by an expert panel. The domains were classified into twenty sub-domains, with 70 input and process indicators to measure performance. Seven sub-domains for assessing health system outputs and outcomes were identified, with a total of 28 indicators. Districts in Haryana state from north India were selected for the study. Primary and secondary data will be collected from 378 health facilities, district and state health directorate headquarters. Indicators will be normalized, aggregated to generate composite performance index at district level. Domain specific scores will present the quality of individual building block domains in the public health system. Robustness of the results will be checked using sensitivity analysis. Expected impact for public health: The study presents a methodology for comprehensive assessment of all health system domains on basis of input, process, output and outcome indicators which has never been reported from India. Generation of this index will help identify policy and implementation areas of concern and point towards potential solutions. Results may also help understand relationships between individual building blocks and their sub-components. Significance for public health Measuring performance of health system is important to understand progress and challenges, and create systems that are efficient, equitable and patient-focused. However, very few assessments of such nature have been observed in low and middle income countries, especially at district level, mainly because of methodological challenges. This study presents a methodology for comprehensive assessment of all domains of health system and generation of a composite Health System Performance Index on the basis of input, process, output and outcome indicators. It will help identify policy and implementation problems worthy of attention and point towards potential solutions to health system bottlenecks resulting in poor performance. The results may also help better understand the relationships between individual building blocks and their sub-components and the overall performance of the health system. PMID:29441330
Colorado Longitudinal Twin Study of Reading Disability
ERIC Educational Resources Information Center
Wadsworth, Sally J.; DeFries, John C.; Olson, Richard K.; Willcutt, Erik G.
2007-01-01
The primary objectives of the present study are to introduce the Colorado Longitudinal Twin Study of Reading Disability, the first longitudinal twin study in which subjects have been specifically selected for having a history of reading difficulties, and to present some initial assessments of the stability of reading performance and cognitive…
U.S. GASOLINE COMPOSITION STUDY
This presentation presents results from a 2004/2005 study of U.S. gasoline composition. Differences in composition are driven by regulation, octane requirements, refining methods, and performance needs. Major differences in composition were traced to a few compounds: benzene, MTB...
School-aged children can benefit from audiovisual semantic congruency during memory encoding.
Heikkilä, Jenni; Tiippana, Kaisa
2016-05-01
Although we live in a multisensory world, children's memory has been usually studied concentrating on only one sensory modality at a time. In this study, we investigated how audiovisual encoding affects recognition memory. Children (n = 114) from three age groups (8, 10 and 12 years) memorized auditory or visual stimuli presented with a semantically congruent, incongruent or non-semantic stimulus in the other modality during encoding. Subsequent recognition memory performance was better for auditory or visual stimuli initially presented together with a semantically congruent stimulus in the other modality than for stimuli accompanied by a non-semantic stimulus in the other modality. This congruency effect was observed for pictures presented with sounds, for sounds presented with pictures, for spoken words presented with pictures and for written words presented with spoken words. The present results show that semantically congruent multisensory experiences during encoding can improve memory performance in school-aged children.
Measurement of health system performance at district level: A study protocol.
Sharma, Atul; Prinja, Shankar; Aggarwal, Arun Kumar
2017-12-13
Limited efforts have been observed in low and middle income countries to undertake health system performance assessment at district level. Absence of a comprehensive data collection tool and lack of a standardised single summary measure defining overall performance are some of the main problems. Present study has been undertaken to develop a summary composite health system performance index at district level. A broad range of indicators covering all six domains as per building block framework were finalized by an expert panel. The domains were classified into twenty sub-domains, with 70 input and process indicators to measure performance. Seven sub-domains for assessing health system outputs and outcomes were identified, with a total of 28 indicators. Districts in Haryana state from north India were selected for the study. Primary and secondary data will be collected from 378 health facilities, district and state health directorate headquarters. Indicators will be normalized, aggregated to generate composite performance index at district level. Domain specific scores will present the quality of individual building block domains in the public health system. Robustness of the results will be checked using sensitivity analysis. The study presents a methodology for comprehensive assessment of all health system domains on basis of input, process, output and outcome indicators which has never been reported from India. Generation of this index will help identify policy and implementation areas of concern and point towards potential solutions. Results may also help understand relationships between individual building blocks and their sub-components.
Busse, Sebastian; Schwarting, Rainer K. W.
2016-01-01
The present study is part of a series of experiments, where we analyze why and how damage of the rat’s dorsal hippocampus (dHC) can enhance performance in a sequential reaction time task (SRTT). In this task, sequences of distinct visual stimulus presentations are food-rewarded in a fixed-ratio-13-schedule. Our previous study (Busse and Schwarting, 2016) had shown that rats with lesions of the dHC show substantially shorter session times and post-reinforcement pauses (PRPs) than controls, which allows for more practice when daily training is kept constant. Since sequential behavior is based on instrumental performance, a sequential benefit might be secondary to that. In order to test this hypothesis in the present study, we performed two experiments, where pseudorandom rather than sequential stimulus presentation was used in rats with excitotoxic dorsal hippocampal lesions. Again, we found enhanced performance in the lesion-group in terms of shorter session times and PRPs. During the sessions we found that the lesion-group spent less time with non-instrumental behavior (i.e., grooming, sniffing, and rearing) after prolonged instrumental training. Also, such rats showed moderate evidence for an extinction impairment under devalued food reward conditions and significant deficits in a response-outcome (R-O)-discrimination task in comparison to a control-group. These findings suggest that facilitatory effects on instrumental performance after dorsal hippocampal lesions may be primarily a result of complex behavioral changes, i.e., reductions of behavioral flexibility and/or alterations in motivation, which then result in enhanced instrumental learning. PMID:27375453
The Influence of Similarity on Visual Working Memory Representations
Lin, Po-Han; Luck, Steven J.
2007-01-01
In verbal memory, similarity between items in memory often leads to interference and impaired memory performance. The present study sought to determine whether analogous interference effects would be observed in visual working memory by varying the similarity of the to-be-remembered objects in a color change-detection task. Instead of leading to interference and impaired performance, increased similarity among the items being held in memory led to improved performance. Moreover, when two similar colors were presented along with one dissimilar color, memory performance was better for the similar colors than for the dissimilar color. Similarity produced better performance even when the objects were presented sequentially and even when memory for the first item in the sequence was tested. These findings show that similarity does not lead to interference between representations in visual working memory. Instead, similarity may lead to improved task performance, possibly due to increased stability or precision of the memory representations during maintenance. PMID:19430536
Castellucci, H I; Arezes, P M; Molenbroek, J F M; de Bruin, R; Viviani, C
2017-01-01
The purpose of this study was to determine, using a systematic review, whether the design and/or dimensions of school furniture affect the students' physical responses and/or their performance. Of the review studies, 64% presented positive results, i.e. proven effects; 24% presented negative effects or no change/effect; and the remaining 12% showed an unclear effect. The compatibility between school furniture dimensions and students' anthropometric characteristics was identified as a key factor for improving some students' physical responses. Design characteristics such as high furniture, sit-stand furniture, and tilt tables and seats also present positive effects. Finally, we concluded that further research should be conducted exploring various aspects of those variables, particularly focusing on more objective measures complemented by controlled and prospective design. Practitioner Summary: A systematic review of the literature presents a clearly positive effect of school furniture dimensions on students' performance and physical responses. Similar results appeared when school furniture design was tested. However, studying the effects of design and dimensions together produced an unclear positive effect.
Relations of Machiavellian behavior with sales performance of stockbrokers.
Aziz, Abdul; May, Kim; Crotts, John C
2002-04-01
The hypothesis of a relationship between Machiavellian behavior and sales performance of Christie and Geis was tested with a sample of 110 stockbrokers. Scores on a measure called the Machiavellian Behavior scale were positively and significantly correlated with two self-reported measures of sales performance of the stock-brokers. Present results together with those of two earlier studies supported the hypothesis that salespeople with a Machiavellian orientation are likely to be more sucessful. Analysis of the data also indicated predictive validity and acceptable internal consistency of the Machiavellian Behavior scale. Limitations of the present study and a need for further research are discussed.
Attentional Focus Effects in Balance Acrobats
ERIC Educational Resources Information Center
Wulf, Gabriele
2008-01-01
Performing and learning motor skills has been shown to be enhanced if the performer adopts an external relative to internal focus (or no focus) of attention (Wulf, 2007). The present study examined the generalizability of this effect to top-level performers (balance acrobats). Participants performed a balance task (standing on an inflated rubber…
Computational study of single-expansion-ramp nozzles with external burning
NASA Astrophysics Data System (ADS)
Yungster, Shaye; Trefny, Charles J.
1992-04-01
A computational investigation of the effects of external burning on the performance of single expansion ramp nozzles (SERN) operating at transonic speeds is presented. The study focuses on the effects of external heat addition and introduces a simplified injection and mixing model based on a control volume analysis. This simplified model permits parametric and scaling studies that would have been impossible to conduct with a detailed CFD analysis. The CFD model is validated by comparing the computed pressure distribution and thrust forces, for several nozzle configurations, with experimental data. Specific impulse calculations are also presented which indicate that external burning performance can be superior to other methods of thrust augmentation at transonic speeds. The effects of injection fuel pressure and nozzle pressure ratio on the performance of SERN nozzles with external burning are described. The results show trends similar to those reported in the experimental study, and provide additional information that complements the experimental data, improving our understanding of external burning flowfields. A study of the effect of scale is also presented. The results indicate that combustion kinetics do not make the flowfield sensitive to scale.
Computational study of single-expansion-ramp nozzles with external burning
NASA Technical Reports Server (NTRS)
Yungster, Shaye; Trefny, Charles J.
1992-01-01
A computational investigation of the effects of external burning on the performance of single expansion ramp nozzles (SERN) operating at transonic speeds is presented. The study focuses on the effects of external heat addition and introduces a simplified injection and mixing model based on a control volume analysis. This simplified model permits parametric and scaling studies that would have been impossible to conduct with a detailed CFD analysis. The CFD model is validated by comparing the computed pressure distribution and thrust forces, for several nozzle configurations, with experimental data. Specific impulse calculations are also presented which indicate that external burning performance can be superior to other methods of thrust augmentation at transonic speeds. The effects of injection fuel pressure and nozzle pressure ratio on the performance of SERN nozzles with external burning are described. The results show trends similar to those reported in the experimental study, and provide additional information that complements the experimental data, improving our understanding of external burning flowfields. A study of the effect of scale is also presented. The results indicate that combustion kinetics do not make the flowfield sensitive to scale.
Verification of CFD model of plane jet used for smoke free zone separation in case of fire
NASA Astrophysics Data System (ADS)
Krajewski, Grzegorz; Suchy, Przemysław
2018-01-01
This paper presents the basic information about the use of air curtains in fire safety, as a barrier for heat and smoke. Mathematical model of an air curtain presented hereallows estimation of velocity of air in various points of space, including the velocity of air from an angled air curtain. Presented equations show how various parameters influence the performance of air curtain. Further, authors present results of their air curtain performance. Authors of that article have done tests in a real scale model. Tests results were used to verify chosen turbulence model and boundary conditions. Results of new studies are presented with regards to the performance of air curtain in case of fire, and final remarks on its design are given.
RFI simulation definition study, exhibit D
NASA Technical Reports Server (NTRS)
Braun, W. R.
1981-01-01
Comparative analyses of experimental and predicted effects of the radio frequency interference (RFI) environment on the Shuttle/TDRSS S-band links were performed. Specifications are defined ad ESTL test requirements are presented. Procedures for using the RFI test generator in the ESTL S-band link tests are presented and performance predictions for these links in the RFI environment are provided.
Impact of Psychological Ownership on the Performance of Business School Lecturers
ERIC Educational Resources Information Center
Md-Sidin, Samsinar; Sambasivan, Murali; Muniandy, Nanthini
2010-01-01
The purpose of the present article is to investigate the impact of psychological ownership, job performance, job commitment, and job satisfaction among business school lecturers of public universities in Malaysia. As psychological ownership is a relatively new concept, the present study expands the use of it in a different setting. Based on the…
ERIC Educational Resources Information Center
Davis, Kelly D.; Winsler, Adam; Middleton, Michael
2006-01-01
In the present study, the authors examined college students' (N = 136) perceptions of the provision of extrinsic rewards given by parents and teachers for academic performance from elementary school through high school. They also examined the relations between reward history and present student motivational orientation. External rewards for…
Investigation of the effects of pile jetting and performing
DOT National Transportation Integrated Search
1999-07-01
This report presents the results of an experimental study performed with similar model piles installed using (1) impact driving (2) jetting and (3) performing in a sandy soil (with 10% clay) compacted to different unit weights under saturated and uns...
Team Pay for Performance: Experimental Evidence from Round Rock's Project on Incentives in Teaching
ERIC Educational Resources Information Center
McCaffrey, Daniel F.; Pane, John F.; Springer, Matthew G.; Burns, Susan F.; Haas, Ann
2011-01-01
This paper presents the results of a rigorous experiment examining the impact of pay for performance on student achievement and instructional practice. This study, conducted by the National Center on Performance Incentives, examines a pay-for-performance program in Round Rock (Texas) which distributed performance awards to teachers based on a…
Lolich, María; Holtzman, Jessica N; Rago, Carlo M; Vázquez, Gustavo H
2015-01-01
In recent years, investigators have begun to consider the possibility of explaining the physiopathology of bipolar disorder from a neuroprogressive perspective. The evidence that supports the feasibility of such an approach is varied, and arises from neuroimaging studies, batteries of neurocognitive evaluations, and tests to identify the specific biomarkers of the disorder. The present article seeks to perform a review of the research that investigates the cognitive deficits in bipolar disorder. A bibliographic revision was performed of articles published between 1990 and 2015. Levels of cognitive performance were explored in both cross-sectional and longitudinal studies. The compiled studies signal the presence of altered cognitive function, even during periods of euthymia. However, there are contradictory results as to whether bipolar disorder presents a degenerative course. New lines of investigation suggest that only a percentage of individuals with bipolar disorder are affected in a progressive manner. It is of paramount importance to perform new longitudinal studies in high-risk populations, so as to validate or refute a neuroprogressive model of cognitive deficits in patients with bipolar disorder.
Afterbody External Aerodynamic and Performance Prediction at High Reynolds Numbers
NASA Technical Reports Server (NTRS)
Carlson, John R.
1999-01-01
This CFD experiment concludes that the potential difference between the flow between a flight Reynolds number test and a sub-scale wind tunnel test are substantial for this particular nozzle boattail geometry. The early study was performed using a linear k-epsilon turbulence model. The present study was performed using the Girimaji formulation of a algebraic Reynolds stress turbulent simulation.
ERIC Educational Resources Information Center
Huang, Shaobo; Fang, Ning
2013-01-01
Predicting student academic performance has long been an important research topic in many academic disciplines. The present study is the first study that develops and compares four types of mathematical models to predict student academic performance in engineering dynamics--a high-enrollment, high-impact, and core course that many engineering…
Exploring rationality in schizophrenia.
Revsbech, Rasmus; Mortensen, Erik Lykke; Owen, Gareth; Nordgaard, Julie; Jansson, Lennart; Sæbye, Ditte; Flensborg-Madsen, Trine; Parnas, Josef
2015-06-01
Empirical studies of rationality (syllogisms) in patients with schizophrenia have obtained different results. One study found that patients reason more logically if the syllogism is presented through an unusual content. To explore syllogism-based rationality in schizophrenia. Thirty-eight first-admitted patients with schizophrenia and 38 healthy controls solved 29 syllogisms that varied in presentation content (ordinary v. unusual) and validity (valid v. invalid). Statistical tests were made of unadjusted and adjusted group differences in models adjusting for intelligence and neuropsychological test performance. Controls outperformed patients on all syllogism types, but the difference between the two groups was only significant for valid syllogisms presented with unusual content. However, when adjusting for intelligence and neuropsychological test performance, all group differences became non-significant. When taking intelligence and neuropsychological performance into account, patients with schizophrenia and controls perform similarly on syllogism tests of rationality. None. © The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.
Implementation and performance test of cloud platform based on Hadoop
NASA Astrophysics Data System (ADS)
Xu, Jingxian; Guo, Jianhong; Ren, Chunlan
2018-01-01
Hadoop, as an open source project for the Apache foundation, is a distributed computing framework that deals with large amounts of data and has been widely used in the Internet industry. Therefore, it is meaningful to study the implementation of Hadoop platform and the performance of test platform. The purpose of this subject is to study the method of building Hadoop platform and to study the performance of test platform. This paper presents a method to implement Hadoop platform and a test platform performance method. Experimental results show that the proposed test performance method is effective and it can detect the performance of Hadoop platform.
ERIC Educational Resources Information Center
Richards, Grant P.
2009-01-01
This study presents the results of a multi-year mixed-methods study of students' performance (n = 94) and experiences (n = 28) with electromagnetics in an elective Electrical and Computer Engineering Technology RF communications course. Data sources used in this study include academic transcripts, course exams, interviews, a learning styles…
Andrews, Suzanne; Leeman, Lawrence; Yonke, Nicole
2017-09-01
Breech presentation affects 3-4% of pregnancies at term and malpresentation is the primary indication for 10-15% of cesarean deliveries. External cephalic version is an effective intervention that can decrease the need for cesarean delivery; however, timely identification of breech presentation is required. We hypothesized that women with a fetus in a breech presentation that is diagnosed after 38 weeks' estimated gestational age have a decreased likelihood of external cephalic version attempted and an increased likelihood of cesarean delivery. This was a retrospective cohort study. A chart review was performed for 251 women with breech presentation at term presenting to our tertiary referral university hospital for external cephalic version, cesarean for breech presentation, or vaginal breech delivery. Vaginal delivery was significantly more likely (31.1% vs 12.5%; P<.01) in women with breech presentation diagnosed before 38 weeks' estimated gestational age as external cephalic version was offered, and subsequently attempted in a greater proportion of women diagnosed before 38 weeks. External cephalic version was more successful when performed by physicians with greater procedural volume during the 3.5 year period of the study (59.1% for providers performing at least 10 procedures vs 31.3% if performing fewer than 10 procedures, P<.01). Results support the need for interventions to increase timely diagnosis of breech presentation as well as improved patient counseling and use of experienced providers for external cephalic version. © 2017 Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Toft, Mark R.
1994-01-01
This is a follow-up of studies of the NASA standard 50 AH cell presented at the NASA battery workshop each of the last two years. This is a dynamic study. Data trends continue to be developed and analyzed for their utility in judging NiCd performance. The trends and parameters presented here may bear relevance to many designs of conventional NiCd batteries, not just the 50 AH and 60 AH sizes.
ERIC Educational Resources Information Center
Ausburn, Floyd B.
A U.S. Air Force study was designed to develop instruction based on the supplantation theory, in which tasks are performed (supplanted) for individuals who are unable to perform them due to their cognitive style. The study examined the effects of linear and multiple imagery in presenting a task requiring visual comparison and location to…
Ghazavi, Zohreh; Hemmati, Zeinab; Hasanpour, Marziyeh; Iranpour, Ramin
2010-01-01
BACKGROUND: Asthma is the most common disease in childhood which is considered as the forerunner of the acute diseases and simply can cause disability among the children. Since childhood and adolescence are the most important periods of growth and perfection and incidence of asthma can bring about distortion in this process, the present study done aimed to assess the effect of conducting high school training program on peers’ performance with asthma. METHODS: This was a quasi-experimental study in which the performance rate of the students at the time of artificial attack of asthma was directly observed, assessed and compared through demographic data questionnaire and performance assessment check list. Eighty individuals from the second grade of high school students in 2010 in Isfahan City were randomly selected to participate in the present study, among which, 40 individuals were entered in the test group and 40 of them also were placed in the control group. After conducting the training program for the test group, which had been designed both by direct method (in person and face to face by asking and answering and group discussion) and by indirect method (using pamphlet and other educational materials), the level of the training effectiveness was assessed on the students’ performance. RESULTS: The findings of the present study indicated that the performance of students at the test group increased from 2.2 (0.6) to 91.8 (1.3) which emphasized that the training program for the young adolescent peers had a positive effect on promoting their health. CONCLUSIONS: Considering the results of the present study and regarding to the importance and role of students as the future makers of the country, and also the cost-effectiveness of the training programs and the positive effect of peers on increasing the level of health among the students with asthma and consequently decreasing the school absence, it obviously seems necessary to generalize and expand these training programs. PMID:22069400
Ilic, Dragan; Rowe, Nicholas
2013-03-01
Poster presentations are a common form of presenting health information at conferences and in the community. Anecdotal evidence within the discipline indicates that health information framed in a poster presentation may be an effective method of knowledge transfer. A state of the art review of the literature was performed to determine the effectiveness of poster presentations on knowledge transfer. Electronic searches of various electronic databases were performed for studies published until 2012. Studies were eligible for inclusion if they provided empirical data on the effectiveness of poster presentations on changes in participant knowledge, attitude or behaviour. A total of 51 studies were identified through the database searches, of which 15 met the inclusion criteria. No study evaluated the effectiveness of posters in comparison with other educational interventions. Most studies utilised a before/after methodology, with the common conclusion that posters elicit greatest effectiveness in knowledge transfer when integrated with other educational modalities. The poster presentation is a commonly used format for communicating information within the academic and public health fields. Evidence from well-designed studies comparing posters to other educational modalities is required to establish an evidence base on the effectiveness of utilising posters in achieving knowledge transfer. © 2013 The authors. Health Information and Libraries Journal © 2013 Health Libraries Group.
ERIC Educational Resources Information Center
Patterson, Michael C.
2017-01-01
The present study investigated the use of multiple digital media technologies, including social networking platforms, by students while preparing for an examination (media multitasking) and the subsequent effects on exam performance. The level of media multitasking (number of simultaneous media technologies) and duration of study were used as…
How Is Family Support Related to Students' GPA Scores? A Longitudinal Study
ERIC Educational Resources Information Center
Cheng, Wen; Ickes, William; Verhofstadt, Lesley
2012-01-01
Previous studies of the influence of family support on college students' academic performance have yielded inconsistent results. Therefore, the present study aimed to examine the link between family support and students' university-level academic performance in a more detailed way. First, we sought to clarify how two distinct aspects of perceived…
Financial Indicators of Reduced Impact Logging Performance in Brazil: Case Study Comparisons
Thomas P. Holmes; Frederick Boltz; Douglas R. Carter
2001-01-01
Indicators of financial performance are compared for three case studies in the Brazilian Amazon. Each case study presents parameters obtained from monitoring initial harvest entries into primary forests for reduced impact logging (RIL) and conventional logging (CL) operations. Differences in cost definitions and data collection protocols complicate the analysis, and...
Visual Thinking and Gender Differences in High School Calculus
ERIC Educational Resources Information Center
Haciomeroglu, Erhan Selcuk; Chicken, Eric
2012-01-01
This study sought to examine calculus students' mathematical performances and preferences for visual or analytic thinking regarding derivative and antiderivative tasks presented graphically. It extends previous studies by investigating factors mediating calculus students' mathematical performances and their preferred modes of thinking. Data were…
Physical phenomena in mercury ion thrusters
NASA Technical Reports Server (NTRS)
Wilbur, P. J.
1979-01-01
Experimental tests results demonstrating that reductions in screen grid thickness enhance the performance of ion thruster grids are presented. Shaping of the screen hole cross section is shown on the other hand not to affect performance substantially. The effect of the magnetic field in the vicinity of the hollow cathode on cathode performance is studied and test results are presented that show reductions in keeper voltages of a few volts can be realized by judicious applications of fields on the order of 100 gauss. The plasma downstream of a SERT 2 thruster operating without high voltage is studied. A model describing electron escape from the thruster under these conditions is discussed. A model defining the performance of the baffle aperture of an ion thruster is refined and experimental verification of the model is undertaken.
On the importance of Task 1 and error performance measures in PRP dual-task studies.
Strobach, Tilo; Schütz, Anja; Schubert, Torsten
2015-01-01
The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.
On the importance of Task 1 and error performance measures in PRP dual-task studies
Strobach, Tilo; Schütz, Anja; Schubert, Torsten
2015-01-01
The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects. PMID:25904890
Personality and job performance: the Big Five revisited.
Hurtz, G M; Donovan, J J
2000-12-01
Prior meta-analyses investigating the relation between the Big 5 personality dimensions and job performance have all contained a threat to construct validity, in that much of the data included within these analyses was not derived from actual Big 5 measures. In addition, these reviews did not address the relations between the Big 5 and contextual performance. Therefore, the present study sought to provide a meta-analytic estimate of the criterion-related validity of explicit Big 5 measures for predicting job performance and contextual performance. The results for job performance closely paralleled 2 of the previous meta-analyses, whereas analyses with contextual performance showed more complex relations among the Big 5 and performance. A more critical interpretation of the Big 5-performance relationship is presented, and suggestions for future research aimed at enhancing the validity of personality predictors are provided.
Intracavity adaptive optics. 1: Astigmatism correction performance.
Spinhirne, J M; Anafi, D; Freeman, R H; Garcia, H R
1981-03-15
A detailed experimental study has been conducted on adaptive optical control methodologies inside a laser resonator. A comparison is presented of several optimization techniques using a multidither zonal coherent optical adaptive technique system within a laser resonator for the correction of astigmatism. A dramatic performance difference is observed when optimizing on beam quality compared with optimizing on power-in-the-bucket. Experimental data are also presented on proper selection criteria for dither frequencies when controlling phase front errors. The effects of hardware limitations and design considerations on the performance of the system are presented, and general conclusions and physical interpretations on the results are made when possible.
Ollendick, Thomas H; Lewis, Krystal M; Cowart, Maria J W; Davis, Thompson
2012-07-01
A host of factors including genetic influences, temperament characteristics, learning experiences, information processing biases, parental psychopathology, and specific parenting practices have been hypothesized to contribute to the development and expression of children's phobias. In the present study, the authors focused on parental psychopathology (phobic anxiety) and parenting behaviors (warmth, involvement) in the prediction of child performance on a behavioral approach test (BAT). All children (n = 44) experienced a phobia of animals and were clinic referred. The youth completed two BATs: the first alone and the second one with a parent present. Overall, performance was greater on the parent-present BAT (58% of steps completed) than on the child-alone BAT (38% of steps completed), although considerable variability was present. Performance on the parent-present BAT was associated with parental warmth and involvement but not parental phobic anxiety. Implications of these findings were discussed, and their implications for the use of behavioral analogues tests were explored.
Performance Stress and the Very Young Musician
ERIC Educational Resources Information Center
Boucher, Helene; Ryan, Charlene A.
2011-01-01
Performance anxiety is a common experience among musicians. Recent studies have found it to be an issue not only for adult performers but also for developing musicians as early as third grade. The question as to its developed or innate nature led to the present inquiry pertaining to young children's responses to performance situations. Sixty-six…
Declining Trends in Student Performance in Lower Secondary Education
ERIC Educational Resources Information Center
Wijsman, Lindy A.; Warrens, Matthijs J.; Saab, Nadira; van Driel, Jan H.; Westenberg, P. Michiel
2016-01-01
Student performance is related to motivation to learn. As motivation generally declines during lower secondary education, one might expect performance to decline as well during this period. Though, until now, it has been unclear whether this pattern exists. In the present study, we examined student performance during the early years of secondary…
Executive Function and Children's Understanding of False Belief: How Specific Is the Relation?
ERIC Educational Resources Information Center
Muller, U.; Zelazo, P.D.; Imrisek, S.
2005-01-01
The present study examined developmental relations among understanding false belief, understanding ''false'' photographs, performance on the Dimensional Change Card Sort (DCCS), and performance on a picture-sentence verification task in 69 3-5-year-old children. Results showed that performance on the DCCS predicted performance on false belief…
Current Developments in Community College Performance Funding
ERIC Educational Resources Information Center
D'Amico, Mark M.; Friedel, Janice N.; Katsinas, Stephen G.; Thornton, Zoë M.
2014-01-01
Since the initiation of performance funding in Tennessee in the late 1970s, approximately 30 states have, at some point, attempted a funding model that includes performance on a set of indicators. The purpose of the present study was to capture the current status of performance funding in public statewide community college systems and to assess…
Performance Management in the French System of Secondary-Teacher Training
ERIC Educational Resources Information Center
Tchibozo, Guy
2005-01-01
The present study focuses on performance analysis and performance management in teacher training in France. After a brief summary of the French system of secondary-teacher training, determinants affecting performance are analyzed. The analysis shows that three determinants--the number of external competitors, the size of a department and the…
A Testing Effect with Multimedia Learning
ERIC Educational Resources Information Center
Johnson, Cheryl I.; Mayer, Richard E.
2009-01-01
A testing effect occurs when a learner performs better on a retention test after studying the material and taking a practice-retention test than after studying the material twice. In the present study, 282 participants watched a narrated animation about lightning formation and then watched the presentation again (restudy), took a…
Flight Performance During Exposure to Acute Hypobaric Hypoxia.
Steinman, Yuval; van den Oord, Marieke H A H; Frings-Dresen, Monique H W; Sluiter, Judith K
2017-08-01
The purpose of the present study was to examine the influence of hypobaric hypoxia (HH) on a pilot's flight performance during exposure to simulated altitudes of 91, 3048, and 4572 m (300, 10,000, and 15,000 ft) and to monitor the pilot's physiological reactions. In a single-blinded counter-balanced design, 12 male pilots were exposed to HH while flying in a flight simulator that had been placed in a hypobaric chamber. Flight performance of the pilots, pilot's alertness level, Spo2, heart rate (HR), minute ventilation (VE), and breathing frequency (BF) were measured. A significant difference was found in Flight Profile Accuracy (FPA) between the three altitudes. Post hoc analysis showed no significant difference in performance between 91 m and 3048 m. A trend was observed at 4572 m, suggesting a decrease in flight performance at that altitude. Significantly lower alertness levels were observed at the start of the flight at 4572 m compared to 91 m, and at the end of the flight at 4572 m compared to the start at that altitude. Spo2 and BF decreased, and HR increased significantly with altitude. The present study did not provide decisive evidence for a decrease in flight performance during exposure to simulated altitudes of 3048 and 4572 m. However, large interindividual variation in pilots' flight performance combined with a gradual decrease in alertness levels observed in the present study puts into question the ability of pilots to safely fly an aircraft while exposed to these altitudes without supplemental oxygen.Steinman Y, van den Oord MHAH, Frings-Dresen MHW, Sluiter JK. Flight performance during exposure to acute hypobaric hypoxia. Aerosp Med Hum Perform. 2017; 88(8):760-767.
Space shuttle Ku-band integrated rendezvous radar/communications system study
NASA Technical Reports Server (NTRS)
1976-01-01
The results are presented of work performed on the Space Shuttle Ku-Band Integrated Rendezvous Radar/Communications System Study. The recommendations and conclusions are included as well as the details explaining the results. The requirements upon which the study was based are presented along with the predicted performance of the recommended system configuration. In addition, shuttle orbiter vehicle constraints (e.g., size, weight, power, stowage space) are discussed. The tradeoffs considered and the operation of the recommended configuration are described for an optimized, integrated Ku-band radar/communications system. Basic system tradeoffs, communication design, radar design, antenna tradeoffs, antenna gimbal and drive design, antenna servo design, and deployed assembly packaging design are discussed. The communications and radar performance analyses necessary to support the system design effort are presented. Detailed derivations of the communications thermal noise error, the radar range, range rate, and angle tracking errors, and the communications transmitter distortion parameter effect on crosstalk between the unbalanced quadriphase signals are included.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guha, S
This is Phase II of a 3-phase, 3-year program. It is intended to expand, enhance, and accelerate knowledge and capabilities for developing high-performance, two-terminal multijunction amorphous Si alloy modules. We discuss investigations on back reflectors to improve cell performance and investigate uniformity in performance over a 1-sq.-ft. area. We present results on component cell performance, both in the initial and in the light-degraded states, deposited over a 1-sq.-ft. area. The uniformity in deposited is investigated by studying the performance of subcells deposited over the entire area. We also present results on the performance of triple- junction cells and modules. Themore » modules use grid-lines and encapsulants compatible with our production technology. We discuss the novel laser-processing technique that has bee developed at United Solar to improve energy-conversion efficiency and reduce manufacturing costs. We discuss in detail the optimization of the processing steps, and the performance of a laser-processed, triple- junction device of 12.6 cm{sup 2} area is presented. We also present experimental results on investigations of module reliability.« less
Some applications of categorical data analysis to epidemiological studies.
Grizzle, J E; Koch, G G
1979-01-01
Several examples of categorized data from epidemiological studies are analyzed to illustrate that more informative analysis than tests of independence can be performed by fitting models. All of the analyses fit into a unified conceptual framework that can be performed by weighted least squares. The methods presented show how to calculate point estimate of parameters, asymptotic variances, and asymptotically valid chi 2 tests. The examples presented are analysis of relative risks estimated from several 2 x 2 tables, analysis of selected features of life tables, construction of synthetic life tables from cross-sectional studies, and analysis of dose-response curves. PMID:540590
ERIC Educational Resources Information Center
Agus, Mirian; Peró-Cebollero, Maribel; Penna, Maria Pietronilla; Guàrdia-Olmos, Joan
2015-01-01
This study aims to investigate about the existence of a graphical facilitation effect on probabilistic reasoning. Measures of undergraduates' performances on problems presented in both verbal-numerical and graphical-pictorial formats have been related to visuo-spatial and numerical prerequisites, to statistical anxiety, to attitudes towards…
ERIC Educational Resources Information Center
Chevalier, Nicolas; James, Tiffany D.; Wiebe, Sandra A.; Nelson, Jennifer Mize; Espy, Kimberly Andrews
2014-01-01
The present study addressed whether developmental improvement in working memory span task performance relies upon a growing ability to proactively plan response sequences during childhood. Two hundred thirteen children completed a working memory span task in which they used a touchscreen to reproduce orally presented sequences of animal names.…
Marone, Jane R; Thakkar, Shivam C; Suliman, Neveen; O'Neill, Shannon I; Doubleday, Alison F
2018-06-01
Poor academic performance from extensive social media usage appears to be due to students' inability to multitask between distractions and academic work. However, the degree to which visually distracted students can acquire lecture information presented aurally is unknown. This study examined the ability of students visually distracted by social media to acquire information presented during a voice-over PowerPoint lecture, and to compare performance on examination questions derived from information presented aurally vs. that presented visually. Students ( n = 20) listened to a 42-min cardiovascular pathophysiology lecture containing embedded cartoons while taking notes. The experimental group ( n = 10) was visually, but not aurally, distracted by social media during times when cartoon information was presented, ~40% of total lecture time. Overall performance among distracted students on a follow-up, open-note quiz was 30% poorer than that for controls ( P < 0.001). When the modality of presentation (visual vs. aural) was compared, performance decreased on examination questions from information presented visually. However, performance on questions from information presented aurally was similar to that of controls. Our findings suggest the ability to acquire information during lecture may vary, depending on the degree of competition between the modalities of the distraction and the lecture presentation. Within the context of current literature, our findings also suggest that timing of the distraction relative to delivery of material examined affects performance more than total distraction time. Therefore, when delivering lectures, instructors should incorporate organizational cues and active learning strategies that assist students in maintaining focus and acquiring relevant information.
Different cerebral connectivity of obese and lean children studied with fMRI
NASA Astrophysics Data System (ADS)
Anaya Moreno, Maryan A.; Hernández López, Javier M.; Hidalgo Tobón, Silvia; Dies Suarez, Pilar; Barragán Pérez, Eduardo; De Celis Alonso, Benito
2014-11-01
In this work we studied the different fMRI brain activations and connections between normal weighted (NW) and obese (OB) infants for different types of food odours. A total of 30 right handed volunteers (infants 8.4±2 years) of both sexes were studied. Infants were divided in two group, one with BMI between 19 and 24 kg/m2 and the other with BMI over 30 kg/m2. The first part of this project consisted of a study in which fMRI BOLD activations to pleasant, neutral and healthy food was performed on both groups. Cerebellum regions were found to be more active in the NW group over the OB when presented with odour cues. OB volunteers in contrast showed larger activations in cingulate cortex structures than their NW counterparts when presented with food odours. The second part of this study performed connectivity studies (ROI to ROI) comparing both groups for each smell. The NW group presented for the onion smell a strong reward anticipation connection between the gustatory cortex and the cingulate cortex which the OB group did not have. In contrast the OB group presented strong orbitofrontal connections (decision making) with gustatory and somatosensory cortex when stimulated with the chocolate odour which the NW did not present. We can conclude that clear differences in fMRI BOLD activation as well as connectivity between the OB and NW groups were found. This points at a very different processing mechanisms of odour cues in infants. To our knowledge this study has never been performed before on infants.
Orbit Transfer Vehicle (OTV) engine, phase A study. Volume 2: Study
NASA Technical Reports Server (NTRS)
Mellish, J. A.
1979-01-01
The hydrogen oxygen engine used in the orbiter transfer vehicle is described. The engine design is analyzed and minimum engine performance and man rating requirements are discussed. Reliability and safety analysis test results are presented and payload, risk and cost, and engine installation parameters are defined. Engine tests were performed including performance analysis, structural analysis, thermal analysis, turbomachinery analysis, controls analysis, and cycle analysis.
Validating Performance Level Descriptors (PLDs) for the AP® Environmental Science Exam
ERIC Educational Resources Information Center
Reshetar, Rosemary; Kaliski, Pamela; Chajewski, Michael; Lionberger, Karen
2012-01-01
This presentation summarizes a pilot study conducted after the May 2011 administration of the AP Environmental Science Exam. The study used analytical methods based on scaled anchoring as input to a Performance Level Descriptor validation process that solicited systematic input from subject matter experts.
NASA Astrophysics Data System (ADS)
Yu, Roger Ho Zhen; Ismail, Mohd Azmi bin; Ramdan, Muhammad Iftishah; Mustaffa, Nur Musfirah binti
2017-03-01
Synthetic Jet generates turbulence flow in cooling the microelectronic devices. In this paper, the experiment investigation of the cooling performance of pneumatic synthetic jet with single slot rectangular orifices at low frequency motion is presented. The velocity profile at the end of the orifice was measured and used as characteristic performance of synthetic jet in the present study. Frequencies of synthetic jet and the compressed air pressure supplied to the pneumatic cylinder (1bar to 5bar) were the parameters of the flow measurement. The air velocity of the synthetic jet was measured by using anemometer air flow meter. The maximum air velocity was 0.5 m/s and it occurred at frequency motion of 8 Hz. The optimum compressed air supplied pressure of the synthetic jet study was 4 bar. The cooling performance of synthetic jet at several driven frequencies from 0 Hz to 8 Hz and heat dissipation between 2.5W and 9W were also investigate in the present study. The results showed that the Nusselt number increased and thermal resistance decreased with both frequency and Reynolds number. The lowest thermal resistance was 5.25°C/W and the highest Nusselt number was 13.39 at heat dissipation of 9W and driven frequency of 8Hz.
Performance evaluation of the NASA/KSC CAD/CAE and office automation LAN's
NASA Technical Reports Server (NTRS)
Zobrist, George W.
1994-01-01
This study's objective is the performance evaluation of the existing CAD/CAE (Computer Aided Design/Computer Aided Engineering) network at NASA/KSC. This evaluation also includes a similar study of the Office Automation network, since it is being planned to integrate this network into the CAD/CAE network. The Microsoft mail facility which is presently on the CAD/CAE network was monitored to determine its present usage. This performance evaluation of the various networks will aid the NASA/KSC network managers in planning for the integration of future workload requirements into the CAD/CAE network and determining the effectiveness of the planned FDDI (Fiber Distributed Data Interface) migration.
Duration of stimulus presentation and screening for perceptual disabilities.
Rohr, M E; Ayers, J B
1975-02-01
This study examined the effects of increasing the stimulus-presentation time of a motion picture test for identifying perceptual disabilities in the performance of Ss in regular first and fourth grade classrooms and on a sample of Ss in special education classes who had been identified as having varying degrees of perceptual deficiencies. The length of stimulus presentation increased the total performance of Ss on the motion picture test but did not add to the value of the instrument as a screening device.
The effect of presentation level on memory performance.
Heinrich, Antje; Schneider, Bruce A
2011-01-01
A loss of speech intelligibility at high presentation levels is called rollover. It is a phenomenon that increases in prevalence as people age. Whether the adverse effect of high presentation levels extends to processes subsequent to speech intelligibility, such as memory, is unknown. The present study examined this question on the basis of the previous finding that older but not younger adults showed memory impairment when acoustically distorted words were presented at 50 dB SL compared with an undistorted baseline presented at 65 dB SPL. One question investigated in the present study was whether a presentation level of 50 dB SL put older listeners at the cusp of rollover and whether this subsequently impaired memory. Moreover, we wanted to know whether and at what level it was possible to induce a similar impairment in younger listeners. We used a paired-associate memory paradigm in which five word pairs per list were presented at a rate of 4 secs per word pair. After each list, the first word of one of the pairs was presented again and the listener was asked to recall the second word. Over the course of the experiment, all list positions were tested an equal number of times. The word pairs, which were acoustically distorted using a jittering algorithm, were presented at 40 dB SL to all younger and older participants and just below an uncomfortably loud level for younger listeners only. Intelligibility of the distorted words was equated across age groups for each presentation level. The effect of presentation level on memory performance was investigated and compared with data of a previous study that used the same design but presented the distorted and undistorted words at 50 dB SL to both age groups. A total of 58 younger and 24 older adults were tested in two experiments. The results showed that for older adults, memory performance for distorted words was decreased in all list positions at a presentation level of 50 dB SL compared with 40 dB SL and an undistorted 65 dB SPL baseline. This effect did not occur for younger listeners. However, when younger adults were tested at a very high presentation level, they showed the same memory decrease compared with the baseline as older adults showed for 50 dB SL. A high presentation level of distorted words can adversely affect memory even after intelligibility is equated for. Moreover, older listeners are affected at lower presentation levels. Hence, the choice of sound level, particularly for older listeners, is important and may affect their level of cognitive performance beyond its effects on intelligibility. Higher presentation levels may not always lead to better performance when the task involves recall of words previously heard.
On the Performance Evaluation of 3D Reconstruction Techniques from a Sequence of Images
NASA Astrophysics Data System (ADS)
Eid, Ahmed; Farag, Aly
2005-12-01
The performance evaluation of 3D reconstruction techniques is not a simple problem to solve. This is not only due to the increased dimensionality of the problem but also due to the lack of standardized and widely accepted testing methodologies. This paper presents a unified framework for the performance evaluation of different 3D reconstruction techniques. This framework includes a general problem formalization, different measuring criteria, and a classification method as a first step in standardizing the evaluation process. Performance characterization of two standard 3D reconstruction techniques, stereo and space carving, is also presented. The evaluation is performed on the same data set using an image reprojection testing methodology to reduce the dimensionality of the evaluation domain. Also, different measuring strategies are presented and applied to the stereo and space carving techniques. These measuring strategies have shown consistent results in quantifying the performance of these techniques. Additional experiments are performed on the space carving technique to study the effect of the number of input images and the camera pose on its performance.
Zenouzi, Roman; von der Gablentz, Janina; Heldmann, Marcus; Göttlich, Martin; Weiler-Normann, Christina; Sebode, Marcial; Ehlken, Hanno; Hartl, Johannes; Fellbrich, Anja; Siemonsen, Susanne; Schramm, Christoph; Münte, Thomas F; Lohse, Ansgar W
2018-01-01
In primary biliary cholangitis (PBC) fatigue is a major clinical challenge of unknown etiology. By demonstrating that fatigue in PBC is associated with an impaired cognitive performance, previous studies have pointed out the possibility of brain abnormalities underlying fatigue in PBC. Whether structural brain changes are present in PBC patients with fatigue, however, is unclear. To evaluate the role of structural brain abnormalities in PBC patients severely affected from fatigue we, therefore, performed a case-control cerebral magnetic resonance imaging (cMRI) study and correlated changes of white and grey brain matter with the cognitive and attention performance. 20 female patients with PBC and 20 female age-matched controls were examined in this study. The assessment of fatigue, psychological symptoms, cognitive and attention performance included clinical questionnaires, established cognition tests and a computerized test battery of attention performance. T1-weighted cMRI and diffusion tensor imaging (DTI) scans were acquired with a 3 Tesla scanner. Structural brain alterations were investigated with voxel-based morphometry (VBM) and DTI analyses. Results were correlated to the cognitive and attention performance. Compared to healthy controls, PBC patients had significantly higher levels of fatigue and associated psychological symptoms. Except for an impairment of verbal fluency, no cognitive or attention deficits were found in the PBC cohort. The VBM and DTI analyses revealed neither major structural brain abnormalities in the PBC cohort nor correlations with the cognitive and attention performance. Despite the high burden of fatigue and selected cognitive deficits, the attention performance of PBC patients appears to be comparable to healthy people. As structural brain alterations do not seem to be present in PBC patients with fatigue, fatigue in PBC must be regarded as purely functional. Future studies should evaluate, whether functional brain changes underlie fatigue in PBC.
Sunlight-readable display technology: a dual-use case study
NASA Astrophysics Data System (ADS)
Blanchard, Randall D.
1996-05-01
This paper describes our vision of sunlight readable color display requirements, an alternate technology that offers a high level of performance, and how we implemented it for the military avionics display market. This knowledge base and product development experience was then applied with a comparable level of performance to commercial applications. The successful dual use of this technology for these two diverse markets is presented. Details of the technical commonality and a comparison of the design and performance differences are presented. A basis for specifying the required level of performance for a sunlight readable full color display is discussed. With the objective of providing a high level of image brightness and high ambient light rejection, a display architecture using collimated light is used. The resulting designs of two military cockpit display products, with contrast ratios above 20:1 in sunlight are shown. The performance of a commercial display providing several thousand foot- Lamberts of image brightness is presented.
Numerical Modeling of Pulse Detonation Rocket Engine Gasdynamics and Performance
NASA Technical Reports Server (NTRS)
2003-01-01
This paper presents viewgraphs on the numerical modeling of pulse detonation rocket engines (PDRE), with an emphasis on the Gasdynamics and performance analysis of these engines. The topics include: 1) Performance Analysis of PDREs; 2) Simplified PDRE Cycle; 3) Comparison of PDRE and Steady-State Rocket Engines (SSRE) Performance; 4) Numerical Modeling of Quasi 1-D Rocket Flows; 5) Specific PDRE Geometries Studied; 6) Time-Accurate Thrust Calculations; 7) PDRE Performance (Geometries A B C and D); 8) PDRE Blowdown Gasdynamics (Geom. A B C and D); 9) PDRE Geometry Performance Comparison; 10) PDRE Blowdown Time (Geom. A B C and D); 11) Specific SSRE Geometry Studied; 12) Effect of F-R Chemistry on SSRE Performance; 13) PDRE/SSRE Performance Comparison; 14) PDRE Performance Study; 15) Grid Resolution Study; and 16) Effect of F-R Chemistry on SSRE Exit Species Mole Fractions.
NASA Technical Reports Server (NTRS)
Lee, Seung Man; Park, Chunki; Cone, Andrew Clayton; Thipphavong, David P.; Santiago, Confesor
2016-01-01
This presentation contains the analysis results of NAS-wide fast-time simulations with UAS and VFR traffic for a single day for evaluating the performance of Detect-and-Avoid (DAA) alerting and guidance systems. This purpose of this study was to help refine and validate MOPS alerting and guidance requirements. In this study, we generated plots of all performance metrics that are specified by RTCA SC-228 Minimum Operational Performance Standards (MOPS): 1) to evaluate the sensitivity of alerting parameters on the performance metrics of each DAA alert type: Preventive, Corrective, and Warning alerts and 2) to evaluate the effect of sensor uncertainty on DAA alerting and guidance performance.
Motivating Factors that Affect Enrolment and Student Performance in an ODL Engineering Program
ERIC Educational Resources Information Center
Dadigamuwa, P. R.; Senanayake, Samans
2012-01-01
The present study was carried out to determine the motivating factors for enrolling in an engineering study programme in open and distance learning (ODL) and the factors that affect the students' performance. The study was conducted with two convenient samples of students following distance learning courses in engineering technology, conducted by…
Transfer of Expertise: An Eye Tracking and Think Aloud Study Using Dynamic Medical Visualizations
ERIC Educational Resources Information Center
Gegenfurtner, Andreas; Seppanen, Marko
2013-01-01
Expertise research has produced mixed results regarding the problem of transfer of expertise. Is expert performance context-bound or can the underlying processes be applied to more general situations? The present study tests whether expert performance and its underlying processes transfer to novel tasks within a domain. A mixed method study using…
Adjustment to University and Academic Performance: Brief Report of a Follow-Up Study
ERIC Educational Resources Information Center
Petersen, Il-haam; Louw, Johann; Dumont, Kitty; Malope, Nomxolisi
2010-01-01
This study presents data that extend an earlier analysis of predictors of academic performance from one to three years. None of the adjustment and other psychosocial variables (help-seeking, academic motivation, self-esteem, perceived stress and perceived academic overload) could predict success at university at the end of three years of study.…
Cognitive therapy for performance anxiety.
Rodebaugh, Thomas L; Chambless, Dianne L
2004-08-01
We present and illustrate the major components of cognitive therapy for performance anxiety, focusing on the performance fears of a client treated with a protocol designed for social phobia. The basic supposition of cognitive theory is that a client's thoughts and beliefs about situations maintain distressing feelings, such as anxiety. Changing these beliefs involves detection and disputation of anxiety-provoking thoughts, as well as testing of these thoughts through exposure to feared situations. Through a process of identifying existing beliefs about performance situations and challenging these beliefs, clients can gain a more realistic and less anxiety-producing perspective on performance tasks. Specific techniques, along with common difficulties and potential solutions, are presented in a detailed case study. Copyright 2004 Wiley Periodicals, Inc.
Barbosa, Vanessa M; Campbell, Suzann K; Sheftel, David; Singh, Jaidep; Beligere, Nagamani
2003-01-01
Understanding the natural history of development in children with cerebral palsy (CP) is important for studying the consequences of early intervention. The purpose of this paper is to present results on the Test of Infant Motor Performance (TIMP) from 0-4 months of age and on the Alberta Infant Motor Scale (AIMS) from 3 to 12 months of age in a group of infants later diagnosed as having CP. Ages at which infants with CP were first recognized as having delayed motor performance on each instrument and the stability of performance over time are presented. Clinical implications for using both instruments are discussed.
Khobragade, Sujata; Abas, Adinegara Lutfi; Khobragade, Yadneshwar Sudam
2016-01-01
Learning outcomes after traditional teaching methods were compared with problem-based learning (PBL) among fifth year medical students. Six students participated each in traditional teaching and PBL methods, respectively. Traditional teaching method involved PowerPoint (PPT) presentation and PBL included study on case scenario and discussion. Both methods were effective in improving performance of students. Postteaching, we did not find significant differences in learning outcomes between these two teaching methods. (1) Study was conducted with an intention to find out which method of learning is more effective; traditional or PBL. (2) To assess the level of knowledge and understanding in anemia/zoonotic diseases as against diabetes/hypertension. All the students posted from February 3, 2014, to March 14, 2014, participated in this study. Six students were asked to prepare and present a lecture (PPT) and subsequent week other six students were asked to present PBL. Both groups presented different topics. Since it was a pre- and post-test, same students were taken as control. To maintain uniformity and to avoid bias due cultural diversity, language etc., same questions were administered. After taking verbal consent, all 34 students were given pretest on anemia and zoonotic diseases. Then lecture (PPT) by six students on the same topic was given it followed by posttest questionnaire. Subsequent week pretest was conducted on hypertension and diabetes. Then case scenario presentation and discussion (PBL) was done by different six students followed by posttest. Both the methods were compared. Analysis was done manually and standard error of means and students t -test was used to find out statistical significance. We found statistically significant improvement in performance of students after PPT presentation as well as PBL. Both methods are equally effective. However, Pretest results of students in anemia and zoonotic diseases (Group A) were poor compared to pretest results of students in hypertension and diabetes (Group B). The students who participated in presentation did not influence their performance as they were covering a small part of the topic and there were no differences in their marks compared to other students. We did not find significant differences in outcome after teaching between PBL and traditional methods. Performances of students were poor in anemia and zoonotic diseases which need remedial teaching. Assessment may influence retention ability and performance.
Characterization of plasticized PEO-PAM blend polymer electrolyte system
NASA Astrophysics Data System (ADS)
Dave, Gargi; Kanchan, Dinesh
2017-05-01
Present study reports characterization studies of NaCF3SO3 based PEO-PAM Blend Polymer Electrolyte (BPE) system with varying amount of EC+PC as plasticizer prepared by solution cast technique. Structural analysis and surface topography have been performed using FTIR and SEM studies. To understand, thermal properties, DSC studies have been undertaken in the present paper
Daylighting in Schools: Improving Student Performance and Health at a Price Schools Can Afford.
ERIC Educational Resources Information Center
Plympton, Patricia; Conway, Susan; Epstein, Kyra
This document discusses evidence regarding daylighting and student performance and development, and presents four case studies of schools that have cost effectively implemented daylighting into their buildings. Case studies reveal that design and construction strategies that incorporate daylighting do not significantly increase costs over…
DOT National Transportation Integrated Search
1989-01-01
The climatological study was performed to determine the impact of icing on the performance of the Low Level Winshear Alert System (LLWAS). : This report Presents the Icing Statisctical profile in the form of data tables and histograms of 106 LLWAS si...
DOT National Transportation Integrated Search
1989-09-01
The climatological study was performed to determine the impact of icing on the performance of Low Level Windshear Alert System (LLWAS). : This report presents the icing statistical profile in the form of data tables and histograms of 106 LLWAS sites....
Can We Succeed in Teaching Business Students to Write Effectively?
ERIC Educational Resources Information Center
Pittenger, Khushwant K. S.; Miller, Mary C.; Allison, Jesse
2006-01-01
This article presents the results of a study where business students' writing skills were assessed using an external objective measure in a business communication course. The student performance was disappointing before instructor intervention. After the intervention, student performance improved noticeably. The implications of the study are…
Education Finance Reform, Local Behavior, and Student Performance in Massachusetts
ERIC Educational Resources Information Center
Nguyen-Hoang, Phuong; Yinger, John
2014-01-01
This study examines the impact on student performance of the education finance reform enacted in 1993 in Massachusetts and of school districts' institutional structure. Estimating education expenditure and demand functions, this study presents evidence that changes in the state education aid following the education reform resulted in significantly…
ERIC Educational Resources Information Center
Zhao, Ningning; Valcke, Martin; Desoete, Annemie; Zhu, Chang; Sang, Guoyuan; Verhaeghe, JeanPierre
2014-01-01
The present study aims at exploring predictors influencing mathematics performance. In particular, the study focuses on internal students' characteristics (gender, age, metacognitive experience, mathematics self-efficacy) and external contextual factors (GDP of school location, parents' educational level, teachers' educational level, and teacher…
Music and Spatial Task Performance: A Causal Relationship.
ERIC Educational Resources Information Center
Rauscher, Frances H.; And Others
This research paper reports on testing the hypothesis that music and spatial task performance are causally related. Two complementary studies are presented that replicate and explore previous findings. One study of college students showed that listening to a Mozart sonata induces subsequent short-term spatial reasoning facilitation and tested the…
Guo, Daoyan; Chen, Hong; Long, Ruyin
2016-01-01
In the increasingly competitive environment, top managers' background characteristics are undoubtedly vital factors for company performance. This study examines whether the performance of Chinese listed companies in the energy industry differs with respect to top managers' background characteristics and explores the exact distribution interval of top managers' background characteristics when company performance reaches the highest level. The initial sample was collected from the CSMAR database (2005-2014) for listed companies in the energy industry. After removing the outlier and missing data, the final number of observations was determined as 780. Descriptive statistics were used to investigate the present distribution of top managers' background characteristics, factor analysis was used to determine the dimensions of company performance, and one-way ANOVA was used to analyze the differences in company performance and its dimensions with respect to top managers' background characteristics. The findings show that both the age and length of service of top managers present an increasing trend over the years of the study period, whereas the educational level shows no significant changes. The performance of listed companies has three dimensions: profit performance, growth performance, and operating performance. Companies behave differently with regard to their top managers' background characteristics; when the top manager is 40-45 years old, with a doctoral degree and above, and in the 2nd-3rd year of his service period, his company will achieve a higher level of performance. This study contributes to the growing literature on company performance in the Chinese energy industry by demonstrating the differences in the performance of Chinese listed companies in the energy industry with regard to top managers' background characteristics, and reaching conclusions on the optimum distribution interval of top managers' background characteristics when company performance reaches the highest level. This study also provides a valuable reference for organizational reform and performance enhancement, which are urgent problems for the Chinese energy industry.
Evaluating Faculty Work: Expectations and Standards of Faculty Performance in Research Universities
ERIC Educational Resources Information Center
Hardre, Patricia; Cox, Michelle
2009-01-01
Expectations and the way they are communicated can influence employees' motivation and performance. Previous research has demonstrated individual effects of workplace climate and individual differences on faculty productivity. The present study focused on the characteristics of institutional performance standards, evaluation processes and…
Evaluation and Application of Enhancements to the Performance of the ASDE-3 Radar in Heavy Rain
DOT National Transportation Integrated Search
1982-03-01
This report presents the results of a study performed by the Transportation Systems Center (TSC) to evaluate two proposed enhancements to the performance of the ASDE-3 Radar in heavy rain: Adaptive gain and adaptive clutter thresholding, (operating w...
A major goal of research on the long-term performance of subsurface reactive barriers is to identify standard ground-water monitoring parameters that may be useful indicators of declining performance or impending system failure. Results are presented from studies conducted over ...
ERIC Educational Resources Information Center
Sturges, Linda W.
2010-01-01
The present study investigated the extent to which providing students with individualized performance feedback informed and directed their learning behavior. Individualized performance feedback was delivered to students using curriculum-based measurement progress indicators, either as a visual representation of ongoing performance in the form of a…
ERIC Educational Resources Information Center
Lin, Zhiang; Carley, Kathleen
How should organizations of intelligent agents be designed so that they exhibit high performance even during periods of stress? A formal model of organizational performance given a distributed decision-making environment in which agents encounter a radar detection task is presented. Using this model the performance of organizations with various…
Boon and Bane of Being Sure: The Effect of Performance Certainty and Expectancy on Task Performance
ERIC Educational Resources Information Center
Schindler, Simon; Reinhard, Marc-André; Dickhäuser, Oliver
2016-01-01
Previous research has suggested certainty to be an important factor when investigating effects of level of expectancies on future behavior. With the present study, we addressed the interplay of expectancy certainty and level of expectancies regarding task performance. We assumed that certain performance expectancies provide a better basis for the…
Road weather management performance metrics.
DOT National Transportation Integrated Search
2008-04-29
This report presents the results of a study to identify appropriate measures of performance that can be attributed to the Federal Highway Administrations (FHWA) Road Weather Management Program (RWMP) products and activities. Specifically, the stud...
Common pressure vessel battery performance
NASA Technical Reports Server (NTRS)
Otzinger, B.
1978-01-01
Performance tests run on two common pressure vessel type nickel hydrogen batteries are described and the results presented. The study included: (1) charge retention tests, (2) synchronous eclipse season cycling tests, and (3) temperature differential tests.
The Influence of Colour on Memory Performance: A Review
Dzulkifli, Mariam Adawiah; Mustafar, Muhammad Faiz
2013-01-01
Human cognition involves many mental processes that are highly interrelated, such as perception, attention, memory, and thinking. An important and core cognitive process is memory, which is commonly associated with the storing and remembering of environmental information. An interesting issue in memory research is on ways to enhance memory performance, and thus, remembering of information. Can colour result in improved memory abilities? The present paper highlights the relationship between colours, attention, and memory performance. The significance of colour in different settings is presented first, followed by a description on the nature of human memory. The role of attention and emotional arousal on memory performance is discussed next. The review of several studies on colours and memory are meant to explain some empirical works done in the area and related issues that arise from such studies. PMID:23983571
The influence of colour on memory performance: a review.
Dzulkifli, Mariam Adawiah; Mustafar, Muhammad Faiz
2013-03-01
Human cognition involves many mental processes that are highly interrelated, such as perception, attention, memory, and thinking. An important and core cognitive process is memory, which is commonly associated with the storing and remembering of environmental information. An interesting issue in memory research is on ways to enhance memory performance, and thus, remembering of information. Can colour result in improved memory abilities? The present paper highlights the relationship between colours, attention, and memory performance. The significance of colour in different settings is presented first, followed by a description on the nature of human memory. The role of attention and emotional arousal on memory performance is discussed next. The review of several studies on colours and memory are meant to explain some empirical works done in the area and related issues that arise from such studies.
Single-cell genomic profiling of acute myeloid leukemia for clinical use: A pilot study
Yan, Benedict; Hu, Yongli; Ban, Kenneth H.K.; Tiang, Zenia; Ng, Christopher; Lee, Joanne; Tan, Wilson; Chiu, Lily; Tan, Tin Wee; Seah, Elaine; Ng, Chin Hin; Chng, Wee-Joo; Foo, Roger
2017-01-01
Although bulk high-throughput genomic profiling studies have led to a significant increase in the understanding of cancer biology, there is increasing awareness that bulk profiling approaches do not completely elucidate tumor heterogeneity. Single-cell genomic profiling enables the distinction of tumor heterogeneity, and may improve clinical diagnosis through the identification and characterization of putative subclonal populations. In the present study, the challenges associated with a single-cell genomics profiling workflow for clinical diagnostics were investigated. Single-cell RNA-sequencing (RNA-seq) was performed on 20 cells from an acute myeloid leukemia bone marrow sample. Putative blasts were identified based on their gene expression profiles and principal component analysis was performed to identify outlier cells. Variant calling was performed on the single-cell RNA-seq data. The present pilot study demonstrates a proof of concept for clinical single-cell genomic profiling. The recognized limitations include significant stochastic RNA loss and the relatively low throughput of the current proposed platform. Although the results of the present study are promising, further technological advances and protocol optimization are necessary for single-cell genomic profiling to be clinically viable. PMID:28454300
Simulation study of the ROMPS robot control system
NASA Technical Reports Server (NTRS)
Nguyen, Charles C.; Liu, HUI-I.
1994-01-01
This is a report presenting the progress of a research grant funded by NASA for work performed from June 1, 1993 to August 1, 1993. The report deals with the Robot Operated Material Processing System (ROMPS). It presents results of a computer simulation study conducted to investigate the performance of the control systems controlling the azimuth, elevation, and radial axes of the ROMPS and its gripper. Four study cases are conducted. The first case investigates the control of free motion of the three areas. In the second case, the compliant motion in the elevation axis with the wrist compliant device is studied in terms of position accuracy and impact forces. The third case focuses on the behavior of the control system in controlling the robot motion along the radial axis when pulling the pallet out of the rack. In the fourth case, the compliant motion of the gripper grasping a solid object under the effect of the gripper passive compliance is studied in terms of position accuracy and contact forces. For each of the above cases, a set of PIR gains will be selected to optimize the controller performance and computer simulation results will be presented and discussed.
IR DirectFET Extreme Environments Evaluation Final Report
NASA Technical Reports Server (NTRS)
Burmeister, Martin; Mottiwala, Amin
2008-01-01
In 2007, International Rectifier (IR) introduced a new version of its DirectFET metal oxide semiconductor field effect transistor (MOSFET) packaging. The new version (referred to as 'Version 2') enhances device moisture resistance, makes surface mount (SMT) assembly of these devices to printed wiring boards (PWBs) more repeatable, and subsequent assembly inspection simpler. In the present study, the National Aeronautics Space Administration (NASA) Jet Propulsion Laboratory (JPL), in collaboration with Stellar Microelectronics (Stellar), continued an evaluation of the DirectFET that they started together in 2006. The present study focused on comparing the two versions of the DirectFET and examining the suitability of the DirectFET devices for space applications. This study evaluated both versions of two DirectFET packaged devices that had both been shown in the 2006 study to have the best electrical and thermal properties: the IRF6635 and IRF6644. The present study evaluated (1) the relative electrical and thermal performance of both versions of each device, (2) the performance through high reliability testing, and (3) the performance of these devices in combination with a range of alternate solder alloys in the extreme thermal environments of deep space....
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beshr, M.; Aute, V.; Sharma, V.
Supermarket refrigeration systems have high environmental impact due to their large refrigerant charge and high leak rates. Consequently, the interest in using low GWP refrigerants such as carbon dioxide (CO 2) and new refrigerant blends is increasing. In this study, an open-source Life Cycle Climate Performance (LCCP) framework is presented and used to compare the environmental impact of four supermarket refrigeration systems: a transcritical CO 2 booster system, a cascade CO 2/N-40 system, a combined secondary circuit with central DX N-40/L-40 system, and a baseline multiplex direct expansion system utilizing R-404A and N-40. The study is performed for different climatesmore » within the USA using EnergyPlus to simulate the systems' hourly performance. Finally, further analyses are presented such as parametric, sensitivity, and uncertainty analyses to study the impact of different system parameters on the LCCP.« less
Beshr, M.; Aute, V.; Sharma, V.; ...
2015-04-09
Supermarket refrigeration systems have high environmental impact due to their large refrigerant charge and high leak rates. Consequently, the interest in using low GWP refrigerants such as carbon dioxide (CO 2) and new refrigerant blends is increasing. In this study, an open-source Life Cycle Climate Performance (LCCP) framework is presented and used to compare the environmental impact of four supermarket refrigeration systems: a transcritical CO 2 booster system, a cascade CO 2/N-40 system, a combined secondary circuit with central DX N-40/L-40 system, and a baseline multiplex direct expansion system utilizing R-404A and N-40. The study is performed for different climatesmore » within the USA using EnergyPlus to simulate the systems' hourly performance. Finally, further analyses are presented such as parametric, sensitivity, and uncertainty analyses to study the impact of different system parameters on the LCCP.« less
NASA Astrophysics Data System (ADS)
Routh, Bikash
2018-04-01
The present paper aims at review on different aspects of harmonic drive gear to identify literature gap for future research. The present article is started first making the comparative study of harmonic drive gear over conventional gear, highlighting its historical background, its application, limitation etc. and then describing working principle of each and every components of it with detail dimensioning and modelling. The present article is further extended to study the different design aspects i.e. synthesis of tooth profiles, lubrication, stress, strain, torque, load sharing, kinematics error and vibration in details etc., identifying problems and then suggesting future perspective for the performance improvement of harmonic drive gear.
Influence of the menstrual cycle on flight simulator performance after alcohol ingestion.
Mumenthaler, M S; O'Hara, R; Taylor, J L; Friedman, L; Yesavage, J A
2001-07-01
Previous studies investigating the influence of the menstrual cycle on cognitive functioning of women after alcohol ingestion have obtained inconsistent results. The present study tested the hypothesis that flight simulator performance during acute alcohol intoxication and 8 hours after drinking differs between the menstrual and the luteal phase of the menstrual cycle. White female pilots (N = 24) were tested during the menstrual and the luteal phases of their menstrual cycles. On each test day they performed a baseline simulator flight, consumed 0.67 g/kg ethanol, and performed an acute-intoxication and an 8-hour-carryover simulator flight. Subjects reached highly significant increases in estradiol (E2) as well as progesterone (P) levels during the luteal test day. Yet, there were no significant differences in overall flight performance after alcohol ingestion between the menstrual and luteal phases during acute intoxication or at 8-hour carryover. We found no correlations between E, or P levels and overall flight performance. However, there was a statistically significant Phase x Order interaction: Pilots who started the experiment with their menstrual day were less susceptible to the effects of alcohol during the second test day than were pilots who started with their luteal day. The tested menstrual cycle phases and varying E2 and P levels did not significantly influence postdrink flight performance. Because the present study included a comparatively large sample size and because it involved complex "real world" tasks (piloting an aircraft), we believe that the present findings are important. We hope that our failure to detect menstrual cycle effects will encourage researchers to include women in their investigations of alcohol effects and human performance.
ERIC Educational Resources Information Center
Napoles, Jessica
2013-01-01
The purpose of this study was to examine the influences of presentation modes (audio and visual) on perceptions of expressive choral performance. The stimulus recording included four choral selections, each conducted by a different conductor in two ways: using expressive conducting gestures and using strict conducting gestures. Three groups of…
Bandara, Ruwanthi; Medagama, Arjuna; Munasinghe, Ruwan; Dinamithra, Nandana; Subasinghe, Amila; Herath, Jayantha; Ratnayake, Mahesh; Imbulpitiya, Buddhini; Sulaiman, Ameena
2015-01-15
Sri Lanka is a developing country with a high rate of cardiovascular mortality. It is still largely dependent on thrombolysis for primary management of acute myocardial infarction. The aim of this study was to present current data on the presentation, management, and outcomes of acute ST-segment-elevation myocardial infarction (STEMI) at a tertiary-care hospital in Sri Lanka. Eighty-one patients with acute STEMI presenting to a teaching hospital in Peradeniya, Sri Lanka, were included in this observational study. Median interval between symptom onset and hospital presentation was 60 min (mean 212 min). Thrombolysis was performed in 73% of patients. The most common single reason for not performing thrombolysis was delayed presentation. Median door-to-needle time was 64 min (mean, 98 min). Only 16.9% of patients received thrombolysis within 30 min, and none underwent primary PCI. Over 98% of patients received aspirin, clopidogrel, and a statin on admission. Intravenous and oral beta blockers were rarely used. Follow-up data were available for 93.8% of patients at 1 year. One-year mortality rate was 12.3%. Coronary intervention was performed in only 7.3% of patients post infarction. Late presentation to hospital remains a critical factor in thrombolysis of STEMI patients in Sri Lanka. Thrombolysis was not performed within 30 min of admission in the majority of patients. First-contact physicians should receive further training on effective thrombolysis, and there is an urgent need to explore the ways in which PCI and post-infarction interventions can be incorporated into treatment protocols.
Zahabi, Maryam; Zhang, Wenjuan; Pankok, Carl; Lau, Mei Ying; Shirley, James; Kaber, David
2017-11-01
Many occupations require both physical exertion and cognitive task performance. Knowledge of any interaction between physical demands and modalities of cognitive task information presentation can provide a basis for optimising performance. This study examined the effect of physical exertion and modality of information presentation on pattern recognition and navigation-related information processing. Results indicated males of equivalent high fitness, between the ages of 18 and 34, rely more on visual cues vs auditory or haptic for pattern recognition when exertion level is high. We found that navigation response time was shorter under low and medium exertion levels as compared to high intensity. Navigation accuracy was lower under high level exertion compared to medium and low levels. In general, findings indicated that use of the haptic modality for cognitive task cueing decreased accuracy in pattern recognition responses. Practitioner Summary: An examination was conducted on the effect of physical exertion and information presentation modality in pattern recognition and navigation. In occupations requiring information presentation to workers, who are simultaneously performing a physical task, the visual modality appears most effective under high level exertion while haptic cueing degrades performance.
Review of Methods for Buildings Energy Performance Modelling
NASA Astrophysics Data System (ADS)
Krstić, Hrvoje; Teni, Mihaela
2017-10-01
Research presented in this paper gives a brief review of methods used for buildings energy performance modelling. This paper gives also a comprehensive review of the advantages and disadvantages of available methods as well as the input parameters used for modelling buildings energy performance. European Directive EPBD obliges the implementation of energy certification procedure which gives an insight on buildings energy performance via exiting energy certificate databases. Some of the methods for buildings energy performance modelling mentioned in this paper are developed by employing data sets of buildings which have already undergone an energy certification procedure. Such database is used in this paper where the majority of buildings in the database have already gone under some form of partial retrofitting - replacement of windows or installation of thermal insulation but still have poor energy performance. The case study presented in this paper utilizes energy certificates database obtained from residential units in Croatia (over 400 buildings) in order to determine the dependence between buildings energy performance and variables from database by using statistical dependencies tests. Building energy performance in database is presented with building energy efficiency rate (from A+ to G) which is based on specific annual energy needs for heating for referential climatic data [kWh/(m2a)]. Independent variables in database are surfaces and volume of the conditioned part of the building, building shape factor, energy used for heating, CO2 emission, building age and year of reconstruction. Research results presented in this paper give an insight in possibilities of methods used for buildings energy performance modelling. Further on it gives an analysis of dependencies between buildings energy performance as a dependent variable and independent variables from the database. Presented results could be used for development of new building energy performance predictive model.
Mucinous cystadenoma of the appendix presenting as an umbilical hernia: A case report.
Ren, Bingbing; Meng, Xiangchao; Cao, Z I; Guo, Chunli; Zhang, Zili
2016-06-01
Mucinous cystadenoma of the appendix is a rare condition that develops as a result of proliferation of mucin-secreting cells in an occluded appendix. Mucinous cystadenoma of the appendix presenting as an umbilical hernia is a rare clinical entity. The most common causes of this condition are known to be ascites, hepatitis and cirrhosis; however, the patient in the present study, was diagnosed as hepatitis- and cirrhosis-negative, with no history of chronic coughing or constipation. The aim of the present study was to report a rare case of mucinous cystadenoma of the appendix presenting as an umbilical hernia in a 66-year-old female patient. The patient had a 6-month history of a reducible mass in the umbilical region and was diagnosed with umbilical hernia. Computed tomography and ultrasonography were performed and revealed massive ascites. Ultimately, a laparoscopic appendectomy was performed and borderline mucinous appendiceal cystadenoma of low malignant potential was confirmed. In addition, the present study discussed the association between mucinous cystadenoma of the appendix and umbilical hernia, as well as the diagnostic process and treatment strategies.
Mucinous cystadenoma of the appendix presenting as an umbilical hernia: A case report
REN, BINGBING; MENG, XIANGCHAO; CAO, ZI; GUO, CHUNLI; ZHANG, ZILI
2016-01-01
Mucinous cystadenoma of the appendix is a rare condition that develops as a result of proliferation of mucin-secreting cells in an occluded appendix. Mucinous cystadenoma of the appendix presenting as an umbilical hernia is a rare clinical entity. The most common causes of this condition are known to be ascites, hepatitis and cirrhosis; however, the patient in the present study, was diagnosed as hepatitis- and cirrhosis-negative, with no history of chronic coughing or constipation. The aim of the present study was to report a rare case of mucinous cystadenoma of the appendix presenting as an umbilical hernia in a 66-year-old female patient. The patient had a 6-month history of a reducible mass in the umbilical region and was diagnosed with umbilical hernia. Computed tomography and ultrasonography were performed and revealed massive ascites. Ultimately, a laparoscopic appendectomy was performed and borderline mucinous appendiceal cystadenoma of low malignant potential was confirmed. In addition, the present study discussed the association between mucinous cystadenoma of the appendix and umbilical hernia, as well as the diagnostic process and treatment strategies. PMID:27313766
Managing Performance to Change Behavior
ERIC Educational Resources Information Center
Denisi, Angelo S.
2011-01-01
Performance appraisal systems are often considered primarily in their role as criterion measures for validation studies. Even when they are considered in other organizational roles, there has traditionally been a strong focus on improving the accuracy of the appraisals. The present article argues that the proper focus of performance appraisal is…
Performance Ecologies, Biotic Rights and Retro-Modernisation
ERIC Educational Resources Information Center
Kershaw, Baz
2012-01-01
This article is based on a paper first presented at the Performance Studies international annual conference on Performing Rights at Queen Mary, University of London, 2006. It has been rewritten specially for this themed issue of "RiDE" in light of my research following publication of "Theatre Ecology: Environments and Performance…
The Nexus between the Above-Average Effect and Cooperative Learning in the Classroom
ERIC Educational Resources Information Center
Breneiser, Jennifer E.; Monetti, David M.; Adams, Katharine S.
2012-01-01
The present study examines the above-average effect (Chambers & Windschitl, 2004; Moore & Small, 2007) in assessments of task performance. Participants completed self-estimates of performance and group estimates of performance, before and after completing a task. Participants completed a task individually and in groups. Groups were…
Peer Mentors Can Improve Academic Performance
ERIC Educational Resources Information Center
Asgari, Shaki; Carter, Frederick, Jr.
2016-01-01
The present study examined the relationship between peer mentoring and academic performance. Students from two introductory psychology classes either received (n = 37) or did not receive (n = 36) peer mentoring. The data indicated a consistent improvement in the performance (i.e., grades on scheduled exams) of the mentored group. A similar pattern…
ERIC Educational Resources Information Center
Hung, Wei-Chen; Chao, Chia-An
2007-01-01
This study has reviewed major design approaches for electronic performance support systems and identified two common problems: users' inability to comprehend screen-based material and poorly designed instructional scaffolds. This paper presents a design approach, called the "Matrix-Aided Performance System" ("MAPS"), which enables these problems…
Numerical flow analysis of axial flow compressor for steady and unsteady flow cases
NASA Astrophysics Data System (ADS)
Prabhudev, B. M.; Satish kumar, S.; Rajanna, D.
2017-07-01
Performance of jet engine is dependent on the performance of compressor. This paper gives numerical study of performance characteristics for axial compressor. The test rig is present at CSIR LAB Bangalore. Flow domains are meshed and fluid dynamic equations are solved using ANSYS package. Analysis is done for six different speeds and for operating conditions like choke, maximum efficiency & before stall point. Different plots are compared and results are discussed. Shock displacement, vortex flows, leakage patterns are presented along with unsteady FFT plot and time step plot.
NASA Technical Reports Server (NTRS)
Morris, Robin D.; Hopkins, William D.; Rumbaugh, Duane M.
1991-01-01
The concept of greater performance efficiency for certain mental abilities or processes in one cerebral hemisphere rather than the other is referred to as 'cerebral lateralization'. The experimental paradigm for lateralization research involves the study of patients with one damaged hemisphere, which prevents their performance of a certain task or function; this approach, however, presents many difficulties in extrapolating to brain function in normal patients. Attention is presently given to gender differences in lateralization, cerebral asymmetries in other species, and the evolutionary bases of hemispheric specialization.
Software Engineering Laboratory (SEL) Ada performance study report
NASA Technical Reports Server (NTRS)
Booth, Eric W.; Stark, Michael E.
1991-01-01
The goals of the Ada Performance Study are described. The methods used are explained. Guidelines for future Ada development efforts are given. The goals and scope of the study are detailed, and the background of Ada development in the Flight Dynamics Division (FDD) is presented. The organization and overall purpose of each test are discussed. The purpose, methods, and results of each test and analyses of these results are given. Guidelines for future development efforts based on the analysis of results from this study are provided. The approach used on the performance tests is discussed.
Zhang, Li; Xin, Ziqiang; Feng, Tingyong; Chen, Yinghe; Szűcs, Denes
2018-03-01
Recent studies have highlighted the fact that some tasks used to study symbolic number representations are confounded by judgments about physical similarity. Here, we investigated whether the contribution of physical similarity and numerical representation differed in the often-used symbolic same-different, numerical comparison, physical comparison, and priming tasks. Experiment 1 showed that subjective physical similarity was the best predictor of participants' performance in the same-different task, regardless of simultaneous or sequential presentation. Furthermore, the contribution of subjective physical similarity was larger in a simultaneous presentation than in a sequential presentation. Experiment 2 showed that only numerical representation was involved in numerical comparison. Experiment 3 showed that both subjective physical similarity and numerical representation contributed to participants' physical comparison performance. Finally, only numerical representation contributed to participants' performance in a priming task as revealed by Experiment 4. Taken together, the contribution of physical similarity and numerical representation depends on task demands. Performance primarily seems to rely on numerical properties in tasks that require explicit quantitative comparison judgments (physical or numerical), while physical stimulus properties exert an effect in the same-different task.
Exploring rationality in schizophrenia
Mortensen, Erik Lykke; Owen, Gareth; Nordgaard, Julie; Jansson, Lennart; Sæbye, Ditte; Flensborg-Madsen, Trine; Parnas, Josef
2015-01-01
Background Empirical studies of rationality (syllogisms) in patients with schizophrenia have obtained different results. One study found that patients reason more logically if the syllogism is presented through an unusual content. Aims To explore syllogism-based rationality in schizophrenia. Method Thirty-eight first-admitted patients with schizophrenia and 38 healthy controls solved 29 syllogisms that varied in presentation content (ordinary v. unusual) and validity (valid v. invalid). Statistical tests were made of unadjusted and adjusted group differences in models adjusting for intelligence and neuropsychological test performance. Results Controls outperformed patients on all syllogism types, but the difference between the two groups was only significant for valid syllogisms presented with unusual content. However, when adjusting for intelligence and neuropsychological test performance, all group differences became non-significant. Conclusions When taking intelligence and neuropsychological performance into account, patients with schizophrenia and controls perform similarly on syllogism tests of rationality. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence. PMID:27703730
A micromixer with consistent mixing performance for a wide range of flow rates.
Goovaerts, Robert; Van Assche, Tom; Sonck, Marc; Denayer, Joeri; Desmet, Gert
2015-02-01
A micromixer with consistent mixing performance for a wide range of flow rates is presented. The mixer makes use of internally moving elements, i.e. steel balls that are located in dedicated mixing chambers. Movement is induced by a rotating magnetic field. To get better insight in differences between active and passive mixing, we studied a mixer that can operate in both regimes. A mixing performance study for a range of flow rates along with pressure drop data is presented. The response of the moving elements in regard to the magnetic field is shown experimentally and shows the limitations of earlier modeling studies. Lastly, the estimated power input on the fluids was calculated and allows for a comparison with more well-known convective-type mixers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Comprehensive Analysis Modeling of Small-Scale UAS Rotors
NASA Technical Reports Server (NTRS)
Russell, Carl R.; Sekula, Martin K.
2017-01-01
Multicopter unmanned aircraft systems (UAS), or drones, have continued their explosive growth in recent years. With this growth comes demand for increased performance as the limits of existing technologies are reached. In order to better design multicopter UAS aircraft, better performance prediction tools are needed. This paper presents the results of a study aimed at using the rotorcraft comprehensive analysis code CAMRAD II to model a multicopter UAS rotor in hover. Parametric studies were performed to determine the level of fidelity needed in the analysis code inputs to achieve results that match test data. Overall, the results show that CAMRAD II is well suited to model small-scale UAS rotors in hover. This paper presents the results of the parametric studies as well as recommendations for the application of comprehensive analysis codes to multicopter UAS rotors.
Conceptual Design and Performance Analysis for a Large Civil Compound Helicopter
NASA Technical Reports Server (NTRS)
Russell, Carl; Johnson, Wayne
2012-01-01
A conceptual design study of a large civil compound helicopter is presented. The objective is to determine how a compound helicopter performs when compared to both a conventional helicopter and a tiltrotor using a design mission that is shorter than optimal for a tiltrotor and longer than optimal for a helicopter. The designs are generated and analyzed using conceptual design software and are further evaluated with a comprehensive rotorcraft analysis code. Multiple metrics are used to determine the suitability of each design for the given mission. Plots of various trade studies and parameter sweeps as well as comprehensive analysis results are presented. The results suggest that the compound helicopter examined for this study would not be competitive with a tiltrotor or conventional helicopter, but multiple possibilities are identified for improving the performance of the compound helicopter in future research.
NASA Astrophysics Data System (ADS)
Chan, Hoy-Yen; Vinson, A. A.; Baljit, S. S. S.; Ruslan, M. H.
2018-04-01
Flat plate solar air collector is the most common collector design, which is relatively simpler to fabricate and lower cost. In the present study, perforated plate solar collector was developed to improve the system thermal performance. A glazed perforated plate of 6mm holes diameter with square geometry was designed and installed as the absorber of the collector. The influences of solar radiation intensity and mass flow rate on the thermal performance were investigated. The perforated collector was compared with the flat plate solar collector under the same operating conditions. The highest values of thermal efficiency in this study for the perforated plate (PP) and the flat plate (FP) solar collectors were 59% and 36% respectively, at solar radiation intensity of 846 Wm-2 and mass flow rate of 0.02 kgs-1. Furthermore, PP collector gave better thermal performance compared to FP collector; and compared to previous studies, the present perforated design was compatible with the flat plate with double pass designs.
Implementation of probe data performance measures.
DOT National Transportation Integrated Search
2017-04-03
This report presents results from a 12-month project where three arterial analysis tools based on probe vehicle segment speed data were developed for District 6. A case study of 5 arterials and two incidents was performed.
Recovery of motor performance following startle.
DOT National Transportation Integrated Search
1969-10-01
Sudden, high-intensity sounds, such as those produced by sonic booms, can be quite startling. Although many studies have investigated physiological response to startle, much less is known concerning the effects of startle on performance. The present ...
Hypoxia and performance decrement.
DOT National Transportation Integrated Search
1966-05-01
The concept of time of useful consciousness fails to take into account the progressive decay that occurs in performance under hypoxic conditions. This study, using a means of quantitatively assessing such a decrement, presents data obtained in a seri...
Toxicological evaluation of Cd-based fluorescent nanoprobes by means of in vivo studies
NASA Astrophysics Data System (ADS)
Farias, Patricia M. A.; Ma-Hock, Lan; Landsiedel, Robert; van Ravenzwaay, Bennard
2018-02-01
Cadmium still represents a stigma for many research- and/or industrial applications. Some deleterious effects are attributed to Cadmium. In the present work, highly fluorescent Cadmium sulfide quantum dots are investigated by e.g. physical-chemical characterization. Most important however is their application as fluorescent probes for bio-imaging in living cells and tissues. This work presents their toxicological evaluation by means of in vivo studies. Bio-imaging experiments are performed without any pre-treatment. The toxicological studies performed, strongly indicate that the use of Cadmium based nanoparticles as fluorescent probes may be nonhazardous and not induce side effects for cells/tissues.
Trends in International Mathematics and Science Study and Gendered Math Teaching in Kuwait
ERIC Educational Resources Information Center
Ahmad, Fatimah; Greenhalgh-Spencer, Heather
2017-01-01
This paper argues for a more complex literature around gender and math performance. In order to argue for this complexity, we present a small portion of data from a case study examining the performance of Kuwaiti students on the Trends in International Mathematics and Science Study and on Kuwait national math tests. Westernized discourses suggest…
ERIC Educational Resources Information Center
Zhou, Li; Griffin-Shirley, Nora; Kelley, Pat; Banda, Devender R.; Lan, William Y.; Parker, Amy T.; Smith, Derrick W.
2012-01-01
Introduction: The study presented here explored the relationship between computer and Internet use and the performance on standardized tests by secondary school students with visual impairments. Methods: With data retrieved from the first three waves (2001-05) of the National Longitudinal Transition Study-2, the correlational study focused on…
Development of an ideal observer that incorporates nuisance parameters and processes list-mode data
MacGahan, Christopher Jonathan; Kupinski, Matthew Alan; Hilton, Nathan R.; ...
2016-02-01
Observer models were developed to process data in list-mode format in order to perform binary discrimination tasks for use in an arms-control-treaty context. Data used in this study was generated using GEANT4 Monte Carlo simulations for photons using custom models of plutonium inspection objects and a radiation imaging system. We evaluated observer model performance and then presented using the area under the receiver operating characteristic curve. Lastly, we studied the ideal observer under both signal-known-exactly conditions and in the presence of unknowns such as object orientation and absolute count-rate variability; when these additional sources of randomness were present, their incorporationmore » into the observer yielded superior performance.« less
Performance and control study of a low-pressure-ratio turbojet engine for a drone aircraft
NASA Technical Reports Server (NTRS)
Seldner, K.; Geyser, L. C.; Gold, H.; Walker, D.; Burgner, G.
1972-01-01
The results of analog and digital computer studies of a low-pressure-ratio turbojet engine system for use in a drone vehicle are presented. The turbojet engine consists of a four-stage axial compressor, single-stage turbine, and a fixed area exhaust nozzle. Three simplified fuel schedules and a generalized parameter fuel control for the engine system are presented and evaluated. The evaluation is based on the performance of each schedule or control during engine acceleration from a windmill start at Mach 0.8 and 6100 meters to 100 percent corrected speed. It was found that, because of the higher acceleration margin permitted by the control, the generalized parameter control exhibited the best dynamic performance.
Aptitude and Trait Predictors of Manned and Unmanned Aircraft Pilot Job Performance
2016-04-22
actually fly RPAs. To address this gap, the present study evaluated pre-accession trait (Big Five personality domains) and aptitude (spatial...knowledge, and personality traits that predict successful job performance for manned aircraft pilots also predict successful job performance for RPA...aptitude and personality traits , job performance, remotely-piloted aircraft, unmanned aircraft systems 16. SECURITY CLASSIFICATION OF: 17
ERIC Educational Resources Information Center
Penttinen, Marjaana; Huovinen, Erkki; Ylitalo, Anna-Kaisa
2015-01-01
In the present study, education majors minoring in music education (n = 24) and music performance majors (n =14) read and performed the original version and melodically altered versions of a simple melody in a given tempo. Eye movements during music reading and piano performances were recorded. Errorless trials were analyzed to explore the…
The 2 × 2 Standpoints Model of Achievement Goals
Korn, Rachel M.; Elliot, Andrew J.
2016-01-01
In the present research, we proposed and tested a 2 × 2 standpoints model of achievement goals grounded in the development-demonstration and approach-avoidance distinctions. Three empirical studies are presented. Study 1 provided evidence supporting the structure and psychometric properties of a newly developed measure of the goals of the 2 × 2 standpoints model. Study 2 documented the predictive utility of these goal constructs for intrinsic motivation: development-approach and development-avoidance goals were positive predictors, and demonstration-avoidance goals were a negative predictor of intrinsic motivation. Study 3 documented the predictive utility of these goal constructs for performance attainment: Demonstration-approach goals were a positive predictor and demonstration-avoidance goals were a negative predictor of exam performance. The conceptual and empirical contributions of the present research were discussed within the broader context of existing achievement goal theory and research. PMID:27242641
Yoon, Yang-soo; Li, Yongxin; Kang, Hou-Yong; Fu, Qian-Jie
2011-01-01
Objective The full benefit of bilateral cochlear implants may depend on the unilateral performance with each device, the speech materials, processing ability of the user, and/or the listening environment. In this study, bilateral and unilateral speech performances were evaluated in terms of recognition of phonemes and sentences presented in quiet or in noise. Design Speech recognition was measured for unilateral left, unilateral right, and bilateral listening conditions; speech and noise were presented at 0° azimuth. The “binaural benefit” was defined as the difference between bilateral performance and unilateral performance with the better ear. Study Sample 9 adults with bilateral cochlear implants participated. Results On average, results showed a greater binaural benefit in noise than in quiet for all speech tests. More importantly, the binaural benefit was greater when unilateral performance was similar across ears. As the difference in unilateral performance between ears increased, the binaural advantage decreased; this functional relationship was observed across the different speech materials and noise levels even though there was substantial intra- and inter-subject variability. Conclusions The results indicate that subjects who show symmetry in speech recognition performance between implanted ears in general show a large binaural benefit. PMID:21696329
Lopez-Campos, Jose Luis; Asensio-Cruz, M Isabel; Castro-Acosta, Ady; Calero, Carmen; Pozo-Rodriguez, Francisco
2014-01-01
Clinical audits have emerged as a potential tool to summarize the clinical performance of healthcare over a specified period of time. However, the effectiveness of audit and feedback has shown inconsistent results and the impact of audit and feedback on clinical performance has not been evaluated for COPD exacerbations. In the present study, we analyzed the results of two consecutive nationwide clinical audits performed in Spain to evaluate both the in-hospital clinical care provided and the feedback strategy. The present study is an analysis of two clinical audits performed in Spain that evaluated the clinical care provided to COPD patients who were admitted to the hospital for a COPD exacerbation. The first audit was performed from November-December 2008. The feedback strategy consisted of personalized reports for each participant center, the presentation and discussion of the results at regional, national and international meetings and the creation of health-care quality standards for COPD. The second audit was part of a European study during January and February 2011. The impact of the feedback strategy was evaluated in term of clinical care provided and in-hospital survival. A total of 94 centers participated in the two audits, recruiting 8,143 admissions (audit 1∶3,493 and audit 2∶4,650). The initially provided clinical care was reasonably acceptable even though there was considerable variability. Several diagnostic and therapeutic procedures improved in the second audit. Although the differences were significant, the degree of improvement was small to moderate. We found no impact on in-hospital mortality. The present study describes COPD hospital care in Spanish hospitals and evaluates the impact of peer-benchmarked, individually written and group-oral feedback strategy on the clinical outcomes for treating COPD exacerbations. It describes small to moderate improvements in the clinical care provided to COPD patients with no impact on in-hospital mortality.
Using Blended Learning for Enhancing EFL Prospective Teachers' Pedagogical Knowledge and Performance
ERIC Educational Resources Information Center
Badawi, Mohamed Farrag
2009-01-01
The basic objective of the present study is to investigate the effectiveness of using blended learning model in developing EFL prospective teachers' pedagogical knowledge and performance. The study sample included 38 EFL Saudi prospective teachers (fourth-year students) at the Faculty of Education & Arts, University of Tabuk, KSA. To collect…
ERIC Educational Resources Information Center
Herman, Melissa R.
2009-01-01
The study presented here tested three theories of racial differences in academic performance among monoracial and multiracial high school students. These theories (status attainment, oppositional culture, and educational attitudes) were developed to explain differences in achievement among monoracial groups, but the study tested how the theories…
The Effect of School Design on Student Performance
ERIC Educational Resources Information Center
Ariani, Mohsen Ghasemi; Mirdad, Fatemeh
2016-01-01
The present study aims at exploring the influence of school design on student performance. The participants consisted of 150 students who studied at two Iranian public school and private school in Mashhad City. School Design and Planning Laboratory (SDPL) model of Georgia University (and Tanner (2009)) was used as an appraisal indicator of school…
A Qualitative Analysis of Imitation Performances of Preschoolers with Down Syndrome
ERIC Educational Resources Information Center
Vanvuchelen, Marleen
2016-01-01
A number of studies suggest that imitation is a characteristic strength in children with Down Syndrome (DS). The present study aims to discover whether imitation performances are qualitatively phenotypical in DS. Eight preschoolers with DS were matched on chronological, mental, language and imitation age with 8 preschoolers with intellectual…
Investigating ESL Students' Academic Performance in Tenses
ERIC Educational Resources Information Center
Javed, Muhammad; Ahmad, Atezaz
2013-01-01
The present study intends to assess the ESL students' performance in tenses at secondary school level. Grade 10 students were the target population of the study. A sample of 396 students (255 male and 141 female) was selected through convenience sampling technique from the District of Bahawalnagar, Pakistan. A test focusing on five different types…
Achievement Goals, Learning Strategies and Instrumental Performance
ERIC Educational Resources Information Center
Nielsen, Siw Graabraek
2008-01-01
The current study is a survey of the achievement goals of music students and the manner in which their strategies and instrumental performance relate to these goals. In the context of advanced instrumental learning, the rationale for the present study was to contribute to the literature on motivation in music students, and thereby, help teachers…
Women and the Study of Folklore.
ERIC Educational Resources Information Center
Jordan, Rosan A.; De Caro, F. A.
1986-01-01
Presents a critical overview of academic writing on women and folklore, organized in three categories: (1) literature on images of women in verbal folklore, and the role of negative images in shaping attitudes; (2) research on womens' oral genres and performance and female use of folklore; and (3) studies of women as folk performers and artists.…
Teachers' Ability and Help Attributions and Children's Math Performance and Task Persistence
ERIC Educational Resources Information Center
Tõeväli, Paula-Karoliina; Kikas, Eve
2016-01-01
The present longitudinal study examined the reciprocal relationships between teachers' causal attributions and children's math performance and task persistence. In total, 760 elementary school children and their teachers participated in this study. The children were tested in math twice, at the end of the second and third grades. At both time…
The Relationship between Leadership Skills and Academic Performance among Dyslexic Students
ERIC Educational Resources Information Center
Handy, Rebecca Carranza
2017-01-01
The purpose of this study was to examine the relationship between leadership skills and academic performance among dyslexic students. The sample for the present study was 103 dyslexic children in grades 3 through 8th. These students attended a school in Austin, Texas that solely educates dyslexic students. The researcher administered the…
A Longitudinal Study of Principals' Activities and Student Performance
ERIC Educational Resources Information Center
May, Henry; Huff, Jason; Goldring, Ellen
2012-01-01
Although a substantial amount of research on school leadership has focused on what principals may do to improve teaching and learning, little of this research has explored how principals' time spent on leadership activities may relate to and possibly affect student performance. This article presents results from a 3-year longitudinal study of…
Performance-Based Task Assessment of Higher-Order Proficiencies in Redesigned STEM High Schools
ERIC Educational Resources Information Center
Ernst, Jeremy V.; Glennie, Elizabeth; Li, Songze
2017-01-01
This study explored student abilities in applying conceptual knowledge when presented with structured performance tasks. Specifically, the study gauged proficiency in higher-order applications of students enrolled in earth and environmental science or biology. The student sample was drawn from a Redesigned STEM high school model where a tested…
Effects of Focal Basal Ganglia Lesions on Timing and Force Control
ERIC Educational Resources Information Center
Aparicio, P.; Diedrichsen, J.; Ivry, R.B.
2005-01-01
Studies of basal ganglia dysfunction in humans have generally involved patients with degenerative disorders, notably Parkinson's disease. In many instances, the performance of these patients is compared to that of patients with focal lesions of other brain structures such as the cerebellum. In the present report, we studied the performance of…
ERIC Educational Resources Information Center
Medrich, Elliott A.; Griffith, Jeanne E.
This report addresses two related issues. First, it summarizes the past international studies of mathematics and science, describing each study and its primary results. In place of country by country performance rankings, the report presents the average performance for each country accompanied by an estimate of the statistical error circumscribing…
Organizational Learning and Performance: Understanding Indian Scenario in Present Global Context
ERIC Educational Resources Information Center
Khandekar, Aradhana; Sharma, Anuradha
2006-01-01
Purpose: The purpose of this paper is to show that the role of organizational learning is increasingly becoming crucial for organizational performance. Based on the study of three Indian global firms operating in National Capital Region of Delhi, India, this study explores the correlation of organizational learning with organizational performance…
Amoroso Borges, Bruno Luis; Bortolazzo, Gustavo Luiz; Neto, Hugo Pasin
2018-01-01
The analysis of heart rate variability is important to the investigation of stimuli from the autonomic nervous system. Osteopathy is a form of treatment that can influence this system in healthy individuals as well as those with a disorder or disease. The aim of the present study was to perform a systematic review of the literature regarding the effect of spinal manipulation and myofascial techniques on heart rate variability. Searches were performed of the Pubmed, Scielo, Lilacs, PEDro, Ibesco, Cochrane and Scopus databases for relevant studies. The PEDro scale was used to assess the methodological quality of each study selected. A total of 505 articles were retrieved during the initial search. After an analysis of the abstracts, nine studies were selected for the present review. Based on the findings, osteopathy exerts an influence on the autonomic nervous system depending on the stimulation site and type. A greater parasympathetic response was found when stimulation was performed in the cervical and lumbar regions, whereas a greater sympathetic response was found when stimulation was performed in the thoracic region. Copyright © 2017 Elsevier Ltd. All rights reserved.
Estimating thermal performance curves from repeated field observations
Childress, Evan; Letcher, Benjamin H.
2017-01-01
Estimating thermal performance of organisms is critical for understanding population distributions and dynamics and predicting responses to climate change. Typically, performance curves are estimated using laboratory studies to isolate temperature effects, but other abiotic and biotic factors influence temperature-performance relationships in nature reducing these models' predictive ability. We present a model for estimating thermal performance curves from repeated field observations that includes environmental and individual variation. We fit the model in a Bayesian framework using MCMC sampling, which allowed for estimation of unobserved latent growth while propagating uncertainty. Fitting the model to simulated data varying in sampling design and parameter values demonstrated that the parameter estimates were accurate, precise, and unbiased. Fitting the model to individual growth data from wild trout revealed high out-of-sample predictive ability relative to laboratory-derived models, which produced more biased predictions for field performance. The field-based estimates of thermal maxima were lower than those based on laboratory studies. Under warming temperature scenarios, field-derived performance models predicted stronger declines in body size than laboratory-derived models, suggesting that laboratory-based models may underestimate climate change effects. The presented model estimates true, realized field performance, avoiding assumptions required for applying laboratory-based models to field performance, which should improve estimates of performance under climate change and advance thermal ecology.
Stopping decisions: information order effects on nonfocal evaluations.
Yu, Michael; Gonzalez, Cleotilde
2013-08-01
We investigated how the order in which information is presented affects when a person decides to stop performing a task. A stopping decision is a decision to stop performing a task on the basis of a sequence of cues. Previous order-effects models do not account for how these contexts limit available working memory for making such decisions. Participants decided how long to perform a task known as the Work Hazard Game that began by rewarding points but later cost points if work continued after an unannounced "emergency." An additive sequence of cues indicated the probability of an emergency. Study I involved a three-group design with cue sequences that indicated the same risk at each decision point but whose final cue presented a high, medium, or low probability. Study 2 had a 2 x 2 design with high or low final cues and an easy or a challenging task. In Study I, participants stopped sooner when the most recent cue presented a high rather than low probability (p = .09), despite the same emergency risk. In Study 2, participants stopped sooner when the most recent cue presented a high rather than low probability for the challenging task but not for the easy task (p = .08). Stopping decisions appear sensitive to the most recent cue observed while experiencing task load. Participants responded to the same risks differently only on the basis of a change in presentation. Findings may be relevant for research and training for hazardous jobs, such as subsurface coal mining, fishing, and trucking.
Assessment of Integrated Nozzle Performance
NASA Technical Reports Server (NTRS)
Lambert, H. H.; Mizukami, M.
1999-01-01
This presentation highlights the activities that researchers at the NASA Lewis Research Center (LeRC) have been and will be involved in to assess integrated nozzle performance. Three different test activities are discussed. First, the results of the Propulsion Airframe Integration for High Speed Research 1 (PAIHSR1) study are presented. The PAIHSR1 experiment was conducted in the LeRC 9 ft x l5 ft wind tunnel from December 1991 to January 1992. Second, an overview of the proposed Mixer/ejector Inlet Distortion Study (MIDIS-E) is presented. The objective of MIDIS-E is to assess the effects of applying discrete disturbances to the ejector inlet flow on the acoustic and aero-performance of a mixer/ejector nozzle. Finally, an overview of the High-Lift Engine Aero-acoustic Technology (HEAT) test is presented. The HEAT test is a cooperative effort between the propulsion system and high-lift device research communities to assess wing/nozzle integration effects. The experiment is scheduled for FY94 in the NASA Ames Research Center (ARC) 40 ft x 80 ft Low Speed Wind Tunnel (LSWT).
The Brief History of Environmental Education and Its Changes from 1972 to Present in Iran
ERIC Educational Resources Information Center
Shobeiri, Seyed Mohammad; Meiboudi, Hossein; Kamali, Fatemeh Ahmadi
2014-01-01
The present study investigates environmental education (EE) before and after Iran's Islamic Revolution. The research method is case study, and among the case study methods, historical analysis has been used in this research. A wide array of sources were employed, from government performance reports to documents, records, books, and articles…
Hashemi, Sayed Basir; Rajaeefard, Abdolreza; Norouzpour, Hasan; Tabatabaee, Hamid Reza; Monshizadeh, Leila
2013-03-01
Hearing loss is the most common sensorineural deficiency in human beings. Cochlear implantation is introduced worldwide to treat the severe to profound sensorineural hearing loss, and can result in both speech comprehension and production. The present study aims to determine the effect of cochlear implantation on the improvement of the auditory performance in 2-7 years old children. The present follow-up study is a kind of cohort study which was conducted on 98 children between 2-7 years old who had referred to Fars Cochlear Implantation Center. The patients' information was gathered from their profiles both before and after the operation. The auditory performance score was obtained in 3 stages; 6 months, 1 year, and 2 years after the cochlear implantation through the Cap test. The data was analyzed using the nonparametric Friedman test as well as Mann-Withney, Kruskal-Wallis, and Spearman's Ranks Correlation coefficients. The mean and the median of the auditory performance score of the children who had undergone the cochlear implantation revealed a significant improvement from 6 months to 1 year, and 2 years after the implantation. It showed a significant statistical association between implantation age, type of hearing loss, regular reference, and the length of being present in the rehabilitation program with the auditory performance. It showed no significant association between sex, mother's level of education, being monolingual or bilingual, and family size with the auditory performance. This study revealed that the type of hearing loss, Presence in the rehabilitation program, and the age of cochlear implantation can be major prognostic factors of the response to the treatment, then the country's health policy makers and health planners must executively take into account the infants' hearing screening program during the first 6 month of age.
Optimum performance and potential flow field of hovering rotors
NASA Technical Reports Server (NTRS)
Wu, J. C.; Sigman, R. K.
1975-01-01
Rotor and propeller performance and induced potential flowfields were studied on the basis of a rotating actuator disk concept, with special emphasis on rotors hovering out of ground effect. A new theory for the optimum performance of rotors hovering OGE is developed and presented. An extended theory for the optimum performance of rotors and propellers in axial motion is also presented. Numerical results are presented for the optimum distributions of blade-bound circulation together with axial inflow and ultimate wake velocities for the hovering rotor over the range of thrust coefficient of interest in rotorcraft applications. Shapes of the stream tubes and of the velocities in the slipstream are obtained, using available methods, for optimum and off-optimum circulation distributions for rotors hovering in and out of ground effect. A number of explicit formulae useful in computing rotor and propeller induced flows are presented for stream functions and velocities due to distributions of circular vortices over axi-symmetric surfaces.
Sung, Sun Young; Choi, Jin Nam
2014-01-01
The present study examines the effects of training and development on organizational innovation. We specifically suggest that the training and development investments of an organization affect its innovative performance by promoting various learning practices. We empirically tested our hypothesis by using time-lagged, multi-source data collected from 260 Korean companies that represent diverse industries. Our analysis showed that corporate expenditure for internal training predicts interpersonal and organizational learning practices, which, in turn, increase innovative performance. The data also revealed that the positive relationship between interpersonal and organizational learning practices and innovative performance is stronger within organizations that have stronger innovative climates. By contrast, investment in employee development through financial support for education outside an organization poses a significant negative effect on its innovative performance and no significant effect on learning practices. The present study provides a plausible explanation for a mechanism through which the investment of an organization in employees enhances its innovative performance. Copyright © 2013 The Authors. PMID:25598576
Impact of Lateral Straggle on the Analog/RF Performance of Asymmetric Gate Stack Double Gate MOSFET
NASA Astrophysics Data System (ADS)
Sivaram, Gollamudi Sai; Chakraborty, Shramana; Das, Rahul; Dasgupta, Arpan; Kundu, Atanu; Sarkar, Chandan K.
2016-09-01
This paper presents a systematic comparative study of Analog and RF performances of an underlapped double gate (U-DG) NMOSFET with Gate Stack (GS) for varying straggle lengths. Asymmetric underlap devices (A-U-DG) have been proposed as one of the remedies for reducing Short Channel Effects (SCE's) with the underlap being present towards the source for sub 20 nm devices. However, the Source to Drain (S/D) implant lateral diffusion leads to a variation in the effective underlap length. This paper investigates the impact of variation of straggle length on the Analog and RF parameters of the device. The RF performance is analyzed by considering the intrinsic capacitances (Cgd, Cgs), intrinsic resistances (Rgd, Rgs), transport delay (τm), inductance (Lsd), cutoff frequency (fT), and the maximum frequency of oscillations (fmax). The circuit performance of the devices are also studied. It is seen that the Analog and RF performances of the devices are improved by optimizing the S/D lateral straggle.
Sung, Sun Young; Choi, Jin Nam
2014-04-01
The present study examines the effects of training and development on organizational innovation. We specifically suggest that the training and development investments of an organization affect its innovative performance by promoting various learning practices. We empirically tested our hypothesis by using time-lagged, multi-source data collected from 260 Korean companies that represent diverse industries. Our analysis showed that corporate expenditure for internal training predicts interpersonal and organizational learning practices, which, in turn, increase innovative performance. The data also revealed that the positive relationship between interpersonal and organizational learning practices and innovative performance is stronger within organizations that have stronger innovative climates. By contrast, investment in employee development through financial support for education outside an organization poses a significant negative effect on its innovative performance and no significant effect on learning practices. The present study provides a plausible explanation for a mechanism through which the investment of an organization in employees enhances its innovative performance. Copyright © 2013 The Authors.
ERIC Educational Resources Information Center
National Association of College and University Business Officers, Washington, DC.
This report presents the results of a 1991 study of the performance and management of endowments of colleges and universities. Part I offers information on the data collection and describes several definitions and formula used in the analysis. Part II presents the report's exhibits in two sections the first of which treats endowment…
ERIC Educational Resources Information Center
National Association of College and University Business Officers, Washington, DC.
This report presents the results of a 1992 study of the performance and management of college and university endowments. Part I offers succinct information on the data collection process, provides definitions, and explains the formula used in the analysis. Part II presents the report's exhibits in two sections. The first section describes: (1)…
Huang, Erich P; Wang, Xiao-Feng; Choudhury, Kingshuk Roy; McShane, Lisa M; Gönen, Mithat; Ye, Jingjing; Buckler, Andrew J; Kinahan, Paul E; Reeves, Anthony P; Jackson, Edward F; Guimaraes, Alexander R; Zahlmann, Gudrun
2015-02-01
Medical imaging serves many roles in patient care and the drug approval process, including assessing treatment response and guiding treatment decisions. These roles often involve a quantitative imaging biomarker, an objectively measured characteristic of the underlying anatomic structure or biochemical process derived from medical images. Before a quantitative imaging biomarker is accepted for use in such roles, the imaging procedure to acquire it must undergo evaluation of its technical performance, which entails assessment of performance metrics such as repeatability and reproducibility of the quantitative imaging biomarker. Ideally, this evaluation will involve quantitative summaries of results from multiple studies to overcome limitations due to the typically small sample sizes of technical performance studies and/or to include a broader range of clinical settings and patient populations. This paper is a review of meta-analysis procedures for such an evaluation, including identification of suitable studies, statistical methodology to evaluate and summarize the performance metrics, and complete and transparent reporting of the results. This review addresses challenges typical of meta-analyses of technical performance, particularly small study sizes, which often causes violations of assumptions underlying standard meta-analysis techniques. Alternative approaches to address these difficulties are also presented; simulation studies indicate that they outperform standard techniques when some studies are small. The meta-analysis procedures presented are also applied to actual [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) test-retest repeatability data for illustrative purposes. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Huang, Erich P; Wang, Xiao-Feng; Choudhury, Kingshuk Roy; McShane, Lisa M; Gönen, Mithat; Ye, Jingjing; Buckler, Andrew J; Kinahan, Paul E; Reeves, Anthony P; Jackson, Edward F; Guimaraes, Alexander R; Zahlmann, Gudrun
2017-01-01
Medical imaging serves many roles in patient care and the drug approval process, including assessing treatment response and guiding treatment decisions. These roles often involve a quantitative imaging biomarker, an objectively measured characteristic of the underlying anatomic structure or biochemical process derived from medical images. Before a quantitative imaging biomarker is accepted for use in such roles, the imaging procedure to acquire it must undergo evaluation of its technical performance, which entails assessment of performance metrics such as repeatability and reproducibility of the quantitative imaging biomarker. Ideally, this evaluation will involve quantitative summaries of results from multiple studies to overcome limitations due to the typically small sample sizes of technical performance studies and/or to include a broader range of clinical settings and patient populations. This paper is a review of meta-analysis procedures for such an evaluation, including identification of suitable studies, statistical methodology to evaluate and summarize the performance metrics, and complete and transparent reporting of the results. This review addresses challenges typical of meta-analyses of technical performance, particularly small study sizes, which often causes violations of assumptions underlying standard meta-analysis techniques. Alternative approaches to address these difficulties are also presented; simulation studies indicate that they outperform standard techniques when some studies are small. The meta-analysis procedures presented are also applied to actual [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) test–retest repeatability data for illustrative purposes. PMID:24872353
Stability and Curving Performance of Conventional and Advanced Rail Transit Vehicles
DOT National Transportation Integrated Search
1984-01-01
Analytical studies are presented which compare the curving performance and speed capability of conventional rail transit trucks with self steering (cross-braced) and forced steering (linkages between carbody and wheelsets) radial trucks. Truck curvin...
Performance Assessment of Human and Cattle Associated Quantitative Real-time PCR Assays - slides
The presentation overview is (1) Single laboratory performance assessment of human- and cattle associated PCR assays and (2) A Field Study: Evaluation of two human fecal waste management practices in Ohio watershed.
ERIC Educational Resources Information Center
Phye, Gary D.; Zimmerman, Bonnie B.
Free recall, cued recall, and clustering performance of fourth grade lower socioeconomic black and white children is studied under four conditions of teaching: random presentation, random presentation plus instruction, blocked presentation, and blocked presentation with instruction of categorically related list. Results indicate that both recall…
Factors associated with participation in physical activity among adolescents in Malaysia.
Cheah, Yong Kang; Lim, Hock Kuang; Kee, Chee Cheong; Ghazali, Sumarni Mohd
2016-11-01
The rising prevalence of non-communicable diseases (NCDs) has become a serious public health issue. Among the multi-factorial drivers behind NCDs are modifiable health risk factors, most notably, physical inactivity. In response to the nearly global policy priority of encouraging regular participation in physical activity, the objective of the present study is to examine the factors that determine participation in physical activity among Malaysian adolescents. Nationally representative data consisting of a large sample size was used. A censored regression model was developed to estimate the likelihood of participation and time spent on physical activity. There are significant relationships between physical activity and gender, ethnicity, self-rated academic performance, maternal education, household size and time spent on physical education. The present study provides new insights into the factors affecting physical activity participation among adolescents. Specifically, self-rated excellent academic performance, household size and physical education can increase the likelihood of being physically active. Evidence of the present study implies that policy makers should pay special attention to females, Chinese, adolescents with self-rated poor academic performance and adolescents who have low maternal education.
A Simple Case Study of a Grid Performance System
NASA Technical Reports Server (NTRS)
Aydt, Ruth; Gunter, Dan; Quesnel, Darcy; Smith, Warren; Taylor, Valerie; Biegel, Bryan (Technical Monitor)
2001-01-01
This document presents a simple case study of a Grid performance system based on the Grid Monitoring Architecture (GMA) being developed by the Grid Forum Performance Working Group. It describes how the various system components would interact for a very basic monitoring scenario, and is intended to introduce people to the terminology and concepts presented in greater detail in other Working Group documents. We believe that by focusing on the simple case first, working group members can familiarize themselves with terminology and concepts, and productively join in the ongoing discussions of the group. In addition, prototype implementations of this basic scenario can be built to explore the feasibility of the proposed architecture and to expose possible shortcomings. Once the simple case is understood and agreed upon, complexities can be added incrementally as warranted by cases not addressed in the most basic implementation described here. Following the basic performance monitoring scenario discussion, unresolved issues are introduced for future discussion.
Hot-Fire Testing of a 1N AF-M315E Thruster
NASA Technical Reports Server (NTRS)
Burnside, Christopher G.; Pedersen, Kevin; Pierce, Charles W.
2015-01-01
This hot-fire test continues NASA investigation of green propellant technologies for future missions. To show the potential for green propellants to replace some hydrazine systems in future spacecraft, NASA Marshall Space Flight Center (MSFC) is continuing to embark on hot-fire test campaigns with various green propellant blends. NASA completed a hot-fire test of a 1N AF-M315E monopropellant thruster at the Marshall Space Flight Center in the small altitude test stand located in building 4205. The thruster is a ground test article used for basic performance determination and catalyst studies. The purpose of the hot-fire testing was for performance determination of a 1N size thruster and form a baseline from which to study catalyst performance and life with follow-on testing to be conducted at a later date. The thruster performed as expected. The result of the hot-fire testing are presented in this paper and presentation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Lijuan; Gonder, Jeff; Burton, Evan
This study evaluates the costs and benefits associated with the use of a plug-in hybrid electric bus and determines the cost effectiveness relative to a conventional bus and a hybrid electric bus. A sensitivity sweep analysis was performed over a number of a different battery sizes, charging powers, and charging stations. The net present value was calculated for each vehicle design and provided the basis for the design evaluation. In all cases, given present day economic assumptions, the conventional bus achieved the lowest net present value while the optimal plug-in hybrid electric bus scenario reached lower lifetime costs than themore » hybrid electric bus. The study also performed parameter sensitivity analysis under low market potential assumptions and high market potential assumptions. The net present value of plug-in hybrid electric bus is close to that of conventional bus.« less
Potential Relationship between Passive Plantar Flexor Stiffness and Running Performance.
Ueno, Hiromasa; Suga, Tadashi; Takao, Kenji; Tanaka, Takahiro; Misaki, Jun; Miyake, Yuto; Nagano, Akinori; Isaka, Tadao
2018-02-01
The present study aimed to determine the relationship between passive stiffness of the plantar flexors and running performance in endurance runners. Forty-eight well-trained male endurance runners and 24 untrained male control subjects participated in this study. Plantar flexor stiffness during passive dorsiflexion was calculated from the slope of the linear portion of the torque-angle curve. Of the endurance runners included in the present study, running economy in 28 endurance runners was evaluated by measuring energy cost during three 4-min trials (14, 16, and 18 km/h) of submaximal treadmill running. Passive stiffness of the plantar flexors was significantly higher in endurance runners than in untrained subjects. Moreover, passive plantar flexor stiffness in endurance runners was significantly correlated with a personal best 5000-m race time. Furthermore, passive plantar flexor stiffness in endurance runners was significantly correlated with energy cost during submaximal running at 16 km/h and 18 km/h, and a trend towards such significance was observed at 14 km/h. The present findings suggest that stiffer plantar flexors may help achieve better running performance, with greater running economy, in endurance runners. Therefore, in the clinical setting, passive stiffness of the plantar flexors may be a potential parameter for assessing running performance. © Georg Thieme Verlag KG Stuttgart · New York.
Mental additions and verbal-domain interference in children with developmental dyscalculia.
Mammarella, Irene C; Caviola, Sara; Cornoldi, Cesare; Lucangeli, Daniela
2013-09-01
This study examined the involvement of verbal and visuo-spatial domains in solving addition problems with carrying in a sample of children diagnosed with developmental dyscalculia (DD) divided into two groups: (i) those with DD alone and (ii) those with DD and dyslexia. Age and stage matched typically developing (TD) children were also studied. The addition problems were presented horizontally or vertically and associated with verbal or visuo-spatial information. Study results showed that DD children's performance on mental calculation tasks was more impaired when they tackled horizontally presented addition problems compared to vertically presented ones that are associated to verbal domain involvement. The performance pattern in the two DD groups was found to be similar. The theoretical, clinical and educational implications of these findings are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.
An empirical assessment of high-performing medical groups: results from a national study.
Shortell, Stephen M; Schmittdiel, Julie; Wang, Margaret C; Li, Rui; Gillies, Robin R; Casalino, Lawrence P; Bodenheimer, Thomas; Rundall, Thomas G
2005-08-01
The performance of medical groups is receiving increased attention. Relatively little conceptual or empirical work exists that examines the various dimensions of medical group performance. Using a national database of 693 medical groups, this article develops a scorecard approach to assessing group performance and presents a theory-driven framework for differentiating between high-performing versus low-performing medical groups. The clinical quality of care, financial performance, and organizational learning capability of medical groups are assessed in relation to environmental forces, resource acquisition and resource deployment factors, and a quality-centered culture. Findings support the utility of the performance scorecard approach and identification of a number of key factors differentiating high-performing from low-performing groups including, in particular, the importance of a quality-centered culture and the requirement of outside reporting from third party organizations. The findings hold a number of important implications for policy and practice, and the framework presented provides a foundation for future research.
Williams, A Mark; Ericsson, K Anders
2005-06-01
The number of researchers studying perceptual-cognitive expertise in sport is increasing. The intention in this paper is to review the currently accepted framework for studying expert performance and to consider implications for undertaking research work in the area of perceptual-cognitive expertise in sport. The expert performance approach presents a descriptive and inductive approach for the systematic study of expert performance. The nature of expert performance is initially captured in the laboratory using representative tasks that identify reliably superior performance. Process-tracing measures are employed to determine the mechanisms that mediate expert performance on the task. Finally, the specific types of activities that lead to the acquisition and development of these mediating mechanisms are identified. General principles and mechanisms may be discovered and then validated by more traditional experimental designs. The relevance of this approach to the study of perceptual-cognitive expertise in sport is discussed and suggestions for future work highlighted.
Sex Differences in Arithmetical Performance Scores: Central Tendency and Variability
ERIC Educational Resources Information Center
Martens, R.; Hurks, P. P. M.; Meijs, C.; Wassenberg, R.; Jolles, J.
2011-01-01
The present study aimed to analyze sex differences in arithmetical performance in a large-scale sample of 390 children (193 boys) frequenting grades 1-9. Past research in this field has focused primarily on average performance, implicitly assuming homogeneity of variance, for which support is scarce. This article examined sex differences in…
OUTSELVES Linked: Cultural Alienation in Literary Performance
ERIC Educational Resources Information Center
Gewaily, M.
2014-01-01
This article is a study of the relationship between the self and its others. It aims to reconsider the two major principles of relevance and context to present a human relationship between the art of communicative performance and the art of cognitive competence throughout some mental representations in literary performances. The article here draws…
The Influence of Virtual Learning Environments in Students' Performance
ERIC Educational Resources Information Center
Alves, Paulo; Miranda, Luísa; Morais, Carlos
2017-01-01
This paper focuses mainly on the relation between the use of a virtual learning environment (VLE) and students' performance. Therefore, virtual learning environments are characterised and a study is presented emphasising the frequency of access to a VLE and its relation with the students' performance from a public higher education institution…
Gender Similarities in Math Performance from Middle School through High School
ERIC Educational Resources Information Center
Scafidi, Tony; Bui, Khanh
2010-01-01
Using data from 10 states, Hyde, Lindberg, Linn, Ellis, and Williams (2008) found gender similarities in performance on standardized math tests. The present study attempted to replicate this finding with national data and to extend it by examining whether gender similarities in math performance are moderated by race, socioeconomic status, or math…
Learning Capability and Business Performance: A Non-Financial and Financial Assessment
ERIC Educational Resources Information Center
Ma Prieto, Isabel; Revilla, Elena
2006-01-01
Purpose: There has been little research that includes reliable deductions about the positive influence of learning capability on business performance. For this reason, the main objective of the present study is to empirically explore the link between learning capability in organizations and business performance evaluated in both financial and…
ERIC Educational Resources Information Center
Valadez Sierra, Maria de los Dolores; Borges del Rosal, Maria Africa; Ruvalcaba Romero, Norma; Villegas, Karina; Lorenzo, Maryurena
2013-01-01
Introduction: Emotional intelligence has been linked to several variables, such as gender, and academic performance. In the area of high intellectual abilities, the literature shows controversy, without a unanimous result on the relationship between both variables. In the present study we analyzed the modulatory effect has academic performance in…
JOB PERFORMANCE AIDS AND THEIR IMPACT ON MANPOWER UTILIZATION.
ERIC Educational Resources Information Center
CHALUPSKY, ALBERT B.; KOPF, THOMAS J.
THE PURPOSE OF THE STUDY WAS TO REVIEW AND SYNTHESIZE THE RESULTS OF RESEARCH ON JOB PERFORMANCE AIDS AND EXPLORE THEIR CURRENT AND POTENTIAL ON INDUSTRIAL MANPOWER UTILIZATION. JOB PERFORMANCE AIDS ARE AUXILIARY INFORMATION STORAGE DEVICES WHICH PRESENT JOB INSTRUCTIONS OR REFERENCE DATA FOR USE BY THE EMPLOYEE DURING THE COURSE OF HIS JOB…
Improved Fuzzy Modelling to Predict the Academic Performance of Distance Education Students
ERIC Educational Resources Information Center
Yildiz, Osman; Bal, Abdullah; Gulsecen, Sevinc
2013-01-01
It is essential to predict distance education students' year-end academic performance early during the course of the semester and to take precautions using such prediction-based information. This will, in particular, help enhance their academic performance and, therefore, improve the overall educational quality. The present study was on the…
Action and Thought in Cello Playing: An Investigation of Children's Practice and Performance
ERIC Educational Resources Information Center
Lisboa, Tania
2008-01-01
This article presents a longitudinal case study investigation of three young cellists' self-directed preparation of a new piece of music for an informal performance. The investigation considers how musical understanding starts to emerge in children's practice and performance. It explores practice at early stages of learning and examines the…
The Visibility and Invisibility of Performance Management in Schools
ERIC Educational Resources Information Center
Page, Damien
2015-01-01
This article presents findings from a study of performance management in 10 schools, five primary and five secondary. The aim was to gain a snapshot of how headteachers are interpreting and implementing the reforms to the performance and capability procedures for teachers introduced in September 2013. The findings suggest that the evaluation of…
ERIC Educational Resources Information Center
And Others; Townsend, J. William
1974-01-01
The present study investigated the efficiency of various existing measures, mainly psychological tests, for predicting job performance of mentally retarded workers in a sheltered occupational shop. Results indicated that existing measures are predictive of performance on some but not all jobs in a sheltered workshop. (Author)
ERIC Educational Resources Information Center
Natale, Katja; Viljaranta, Jaana; Lerkkanen, Marja-Kristiina; Poikkeus, Anna-Maija; Nurmi, Jari-Erik
2009-01-01
The present study investigated whether kindergarten teachers' causal attributions would predict children's reading-related task motivation and performance, or whether it is rather children's motivation and performance that contribute to teachers' causal attributions. To investigate this, 69 children (five to six years old at baseline) and their…
Implementing New Performance Pay-Based Schemes in Higher Educational Institutions
ERIC Educational Resources Information Center
Minasyan, Eva T.; Midova, Venera O.; Danko, Olga A.; Balakhanova, Dariko K.
2017-01-01
The paper presents a review of the study and practice pertaining to the effectiveness of performance-related pay with a particular emphasis on higher educational organizations. The overall research question guiding the review was to establish the extent to which performance pay-based practices have been successful undergoing great changes in…
ERIC Educational Resources Information Center
Maddox, Alexia; Zhao, Linlin
2017-01-01
This case study presents a conceptual model of researcher performance developed by Deakin University Library, Australia. The model aims to organize research performance data into meaningful researcher profiles, referred to as researcher typologies, which support the demonstration of research impact and value. Three dimensions shaping researcher…
NASA Technical Reports Server (NTRS)
Jones, C. B.; Smetana, F. O.
1977-01-01
The performance and estimated material costs for several solar preheaters for domestic hot water heaters using isolation levels present in North Carolina are presented. The effects of monthly variations in isolation and the direction of incident radiation are included. Demand is assumed at 13 gallons (49.2 liters) per day per person. The study shows that a closed circulation system with 82 gallons (310 liters) of preheated storage and 53.4 cu ft (4.94 cu m) of collector surface with single cover can be expected to cost about $800 and to repay it capital cost and interest (at 8%) in 5.2 years, assuming present electric rates increase at 5% per year.
The versatility of a truss mounted mobile transporter for in-space construction
NASA Technical Reports Server (NTRS)
Bush, Harold G.; Lake, Mark S.; Watson, Judith J.; Heard, Walter L., Jr.
1988-01-01
The Mobile Transporter (MT) evolution from early erectable structures assembly activities is detailed. The MT operational features which are required to support astronauts performing on-orbit structure construction or spacecraft assembly functions are presented and discussed. Use of the MT to perform a variety of assembly functions is presented. Estimated EVA assembly times for a precision segmented reflector approximately 20 m in diameter are presented. The EVA/MT technique under study for construction of the reflector (and the entire spacecraft) is illustrated. Finally, the current status of development activities and test results involving the MT and Space Station structural assembly are presented.
Neural correlates of anticipation and processing of performance feedback in social anxiety.
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. © 2014 Wiley Periodicals, Inc.
Synthesis of major economic studies of residential photovoltaics
NASA Technical Reports Server (NTRS)
1984-01-01
Six studies that analyze the cost effectiveness of grid connected residential photovoltaic systems are reviewed. These six studies were selected based on two criteria. First, the reports share common emphases on developing photovoltaic systems with certain engineering design goals in mind, and on performing economic analyses to assess the long term economic potential of the system design. The economic analyses presented are performed from the consumer's perspective.
Aerodynamics of the EXPERT Re-Entry Ballistic Vehicle
NASA Astrophysics Data System (ADS)
Kharitonov, A. M.; Adamov, N. P.; Mazhul, I. I.; Vasenyov, L. G.; Zvegintsev, V. I.; Muylaert, J. M.
2009-01-01
Since 2002 till now, experimental studies of the EXPERT reentry capsule have been performed in ITAM SB RAS wind tunnels. These studies have been performed in consecutive ISTC project No. 2109, 3151, and currently ongoing project No. 3550. The results of earlier studies in ITAM wind tunnels can be found in [1-4]. The present paper describes new data obtained for the EXPERT model.
ERIC Educational Resources Information Center
Hussein, Mohamed Abdel Hadi; Al Ashri, Ismail Ibrahim El shirbini Abdel fattah
2013-01-01
The present study aimed at identifying the necessary writing performance skills for the first year secondary stage students. These skills are necessary for writing the compositions. In this study, the writing conferences and peer response groups strategies were used to develop the students' writing skills, improve their achievement and performance…
SEP ENCKE-87 and Halley rendezvous studies and improved S/C model implementation in HILTOP
NASA Technical Reports Server (NTRS)
Horsewood, J. L.; Mann, F. I.
1978-01-01
Studies were conducted to determine the performance requirements for projected state-of-the-art SEP spacecrafts boosted by the Shuttle/IUS to perform a rendezvous with the comet Halley and a rendezvous with the comet Encke during its 1977 apparition. The spacecraft model of the standard HILTOP computer program was assumed. Numerical and graphical results summarizing the studies are presented.
Shahmoradi, Leila; Ahmadi, Maryam; Sadoughi, Farahnaz; Piri, Zakieh; Gohari, Mahmood Reza
2015-01-01
A knowledge management audit (KMA) is the first phase in knowledge management implementation. Incomplete or incomprehensive execution of the KMA has caused many knowledge management programs to fail. A study was undertaken to investigate how KMAs are performed systematically in organizations and present a comprehensive model for performing KMAs based on a systematic review. Studies were identified by searching electronic databases such as Emerald, LISA, and the Cochrane library and e-journals such as the Oxford Journal and hand searching of printed journals, theses, and books in the Tehran University of Medical Sciences digital library. The sources used in this study consisted of studies available through the digital library of the Tehran University of Medical Sciences that were published between 2000 and 2013, including both Persian- and English-language sources, as well as articles explaining the steps involved in performing a KMA. A comprehensive model for KMAs is presented in this study. To successfully execute a KMA, it is necessary to perform the appropriate preliminary activities in relation to the knowledge management infrastructure, determine the knowledge management situation, and analyze and use the available data on this situation.
NASA Technical Reports Server (NTRS)
Phenneger, M. C.; Singhal, S. P.; Lee, T. H.; Stengle, T. H.
1985-01-01
The work performed by the Attitude Determination and Control Section at the National Aeronautics and Space Administration/Goddard Space Flight Center in analyzing and evaluating the performance of infrared horizon sensors is presented. The results of studies performed during the 1960s are reviewed; several models for generating the Earth's infrared radiance profiles are presented; and the Horizon Radiance Modeling Utility, the software used to model the horizon sensor optics and electronics processing to computer radiance-dependent attitude errors, is briefly discussed. Also provided is mission experience from 12 spaceflight missions spanning the period from 1973 to 1984 and using a variety of horizon sensing hardware. Recommendations are presented for future directions for the infrared horizon sensing technology.
Cue-induced smoking urges deplete cigarette smokers' self-control resources.
Hagger, Martin S; Leaver, Eamonn; Esser, Kerstin; Leung, Chung-Ming; Te Pas, Nina; Keatley, David A; Chan, Derwin K-C; Chatzisarantis, Nikos L D
2013-12-01
Exposure to smoking-related cues leads to increased urge to smoke in regular cigarette smokers and resisting these urges requires considerable self-control. Adopting a resource depletion model, two studies tested the hypothesis that resisting smoking urges depletes self-control resources. Adopting a within-participants randomized cross-over design, participants (study 1, N = 19; study 2, N = 32) were exposed to smoking-related (study 1: smoking images; study 2: cigarette cue-exposure task) and neutral (study 1: neutral images; study 2: drinking-straw task) cues with presentation order randomized. After each cue set, participants completed self-control tasks (study 1: handgrip task; study 2: handgrip and Stroop tasks), performance on which constituted dependent measures of self-control. Self-control task performance was significantly impaired when exposed to smoking-related cues compared to neutral cues. No significant presentation-order effects, or interaction effects between stimulus and presentation order, were found. Findings corroborate our hypothesis that resisting smoking urges depletes cigarette smokers' self-control resources and suggests that self-control capacity is governed by a limited resource.
Context Switching with Multiple Register Windows: A RISC Performance Study
NASA Technical Reports Server (NTRS)
Konsek, Marion B.; Reed, Daniel A.; Watcharawittayakul, Wittaya
1987-01-01
Although previous studies have shown that a large file of overlapping register windows can greatly reduce procedure call/return overhead, the effects of register windows in a multiprogramming environment are poorly understood. This paper investigates the performance of multiprogrammed, reduced instruction set computers (RISCs) as a function of window management strategy. Using an analytic model that reflects context switch and procedure call overheads, we analyze the performance of simple, linearly self-recursive programs. For more complex programs, we present the results of a simulation study. These studies show that a simple strategy that saves all windows prior to a context switch, but restores only a single window following a context switch, performs near optimally.
Performance Improvement Through Indexing of Turbine Airfoils. Part 2; Numerical Simulation
NASA Technical Reports Server (NTRS)
Griffin, Lisa W.; Huber, Frank W.; Sharma, Om P.
1996-01-01
An experimental/analytical study has been conducted to determine the performance improvements achievable by circumferentially indexing succeeding rows of turbine stator airfoils. A series of tests was conducted to experimentally investigate stator wake clocking effects on the performance of the space shuttle main engine (SSME) alternate turbopump development (ATD) fuel turbine test article (TTA). The results from this study indicate that significant increases in stage efficiency can be attained through application of this airfoil clocking concept. Details of the experiment and its results are documented in part 1 of this paper. In order to gain insight into the mechanisms of the performance improvement, extensive computational fluid dynamics (CFD) simulations were executed. The subject of the present paper is the initial results from the CFD investigation of the configurations and conditions detailed in part 1 of the paper. To characterize the aerodynamic environments in the experimental test series, two-dimensional (2D), time accurate, multistage, viscous analyses were performed at the TTA midspan. Computational analyses for five different circumferential positions of the first stage stator have been completed. Details of the computational procedure and the results are presented. The analytical results verify the experimentally demonstrated performance improvement and are compared with data whenever possible. Predictions of time-averaged turbine efficiencies as well as gas conditions throughout the flow field are presented. An initial understanding of the turbine performance improvement mechanism based on the results from this investigation is described.
Stringham, James M; Garcia, Paul V; Smith, Peter A; McLin, Leon N; Foutch, Brian K
2011-09-22
One theory of macular pigment's (MP) presence in the fovea is to improve visual performance in glare. This study sought to determine the effect of MP level on three aspects of visual performance in glare: photostress recovery, disability glare, and visual discomfort. Twenty-six subjects participated in the study. Spatial profiles of MP optical density were assessed with heterochromatic flicker photometry. Glare was delivered via high-bright-white LEDs. For the disability glare and photostress recovery portions of the experiment, the visual task consisted of correct identification of a 1° Gabor patch's orientation. Visual discomfort during the glare presentation was assessed with a visual discomfort rating scale. Pupil diameter was monitored with an infrared (IR) camera. MP level correlated significantly with all the outcome measures. Higher MP optical densities (MPODs) resulted in faster photostress recovery times (average P < 0.003), lower disability glare contrast thresholds (average P < 0.004), and lower visual discomfort (P = 0.002). Smaller pupil diameter during glare presentation significantly correlated with higher visual discomfort ratings (P = 0.037). MP correlates with three aspects of visual performance in glare. Unlike previous studies of MP and glare, the present study used free-viewing conditions, in which effects of iris pigmentation and pupil size could be accounted for. The effects described, therefore, can be extended more confidently to real-world, practical visual performance benefits. Greater iris constriction resulted (paradoxically) in greater visual discomfort. This finding may be attributable to the neurobiologic mechanism that mediates the pain elicited by light.
NASA Astrophysics Data System (ADS)
Blanc, A.; de France, G.; Drouet, F.; Jentschel, M.; Köster, U.; Mancuso, C.; Mutti, P.; Régis, J. M.; Simpson, G.; Soldner, T.; Ur, C. A.; Urban, W.; Vancraeyenest, A.
2013-12-01
One way to explore exotic nuclei is to study their structure by performing γ-ray spectroscopy. At the ILL, we exploit a high neutron flux reactor to induce the cold fission of actinide targets. In this process, fission products that cannot be accessed using standard spontaneous fission sources are produced with a yield allowing their detailed study using high resolution γ-ray spectroscopy. This is what was pursued at the ILL with the EXILL (for EXOGAM at the ILL) campaign. In the present work, the EXILL setup and performance will be presented.
Performance Sensitivity Studies on the PIAA Implementation of the High-Contrast Imaging Testbed
NASA Technical Reports Server (NTRS)
Sidick, Erkin; Lou, John; Shaklan, Stuart; Levine, Marie
2010-01-01
This slide presentation reviews the sensitivity studies on the Phase-Induced Amplitude Apodization (PIAA), or pupil mapping using the High-Contrast Imaging Testbed (HCIT). PIAA is a promising technique in high-dynamic range stellar coronagraph. This presentation reports on the investigation of the effects of the phase and rigid-body errors of various optics on the narrowband contrast performance of the PIAA/HCIT hybrid system. The results have shown that the 2-step wavefront control method utilizing 2-DMs is quite effective in compensating the effects of realistic phase and rigid-body errors of various optics
Assessment of User Home Location Geoinference Methods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harrison, Joshua J.; Bell, Eric B.; Corley, Courtney D.
2015-05-29
This study presents an assessment of multiple approaches to determine the home and/or other important locations to a Twitter user. In this study, we present a unique approach to the problem of geotagged data sparsity in social media when performing geoinferencing tasks. Given the sparsity of explicitly geotagged Twitter data, the ability to perform accurate and reliable user geolocation from a limited number of geotagged posts has proven to be quite useful. In our survey, we have achieved accuracy rates of over 86% in matching Twitter user profile locations with their inferred home locations derived from geotagged posts.
Sisco, Howard; Leventhal, Gloria
2007-12-01
The importance of accurate performance appraisals is central to many aspects of personnel activities in organizations. This study examined threats due to past performance to accuracy of evaluation of subsequent performance by raters differing in scores on field dependence. 162 college students were classified as Field-dependent (n = 81) or Field-independent (n = 81), using a median split on the Group Embedded Figures Test. Past performance (a lecture) was good or poor, presented directly via a videotape or indirectly via a written evaluation to the Field-independent or Field-dependent groups. Analysis indicated the hypothesized contrast effect (ratings in the opposite direction from that of prior ratings) in the Direct condition and an unexpected, albeit smaller, contrast effect in the Indirect condition. There were also differential effects of performance, presentation, and field dependency on rating of lecturer's style and ability.
ERIC Educational Resources Information Center
Souchal, Carine; Toczek, Marie-Christine; Darnon, Céline; Smeding, Annique; Butera, Fabrizio; Martinot, Delphine
2014-01-01
Background: Is it possible to reach performance equality between boys and girls in a science class? Given the stereotypes targeting their groups in scientific domains, diagnostic contexts generally lower girls' performance and non-diagnostic contexts may harm boys' performance. Aim: The present study tested the effectiveness of a…
Thomassin, Noémylle; Gonthier, Corentin; Guerraz, Michel; Roulin, Jean-Luc
2015-01-01
Participants with a high working memory span tend to perform better than low spans in a variety of tasks. However, their performance is paradoxically more impaired when they have to perform two tasks at once, a phenomenon that could be labeled the "hard fall effect." The present study tested whether this effect exists in a short-term memory task, and investigated the proposal that the effect is due to high spans using efficient facilitative strategies under simple task conditions. Ninety-eight participants performed a spatial short-term memory task under simple and dual task conditions; stimuli presentation times either allowed for the use of complex facilitative strategies or not. High spans outperformed low spans only under simple task conditions when presentation times allowed for the use of facilitative strategies. These results indicate that the hard fall effect exists on a short-term memory task and may be caused by individual differences in strategy use.
NASA Astrophysics Data System (ADS)
Deng, Zigang; Wang, Jiasu; Zheng, Jun; Zhang, Ya; Wang, Suyu
2013-02-01
Performance improvement is a long-term research task for the promotion of practical application of promising high-temperature superconducting (HTS) magnetic levitation (maglev) vehicle technologies. We studied the feasibility to enhance the performance of present HTS Maglev systems by introducing ferromagnetic materials to onboard bulk superconductors. The principle here is to make use of the high magnetic permeability of ferromagnetic materials to alter the flux distribution of the permanent magnet guideway for the enhancement of magnetic field density at the position of the bulk superconductors. Ferromagnetic iron plates were added to the upper surface of bulk superconductors and their geometric and positioning effects on the maglev performance were investigated experimentally. Results show that the guidance performance (stability) was enhanced greatly for a particular setup when compared to the present maglev system which is helpful in the application where large guidance forces are needed such as maglev tracks with high degrees of curves.
Binaural auditory beats affect vigilance performance and mood.
Lane, J D; Kasian, S J; Owens, J E; Marsh, G R
1998-01-01
When two tones of slightly different frequency are presented separately to the left and right ears the listener perceives a single tone that varies in amplitude at a frequency equal to the frequency difference between the two tones, a perceptual phenomenon known as the binaural auditory beat. Anecdotal reports suggest that binaural auditory beats within the electroencephalograph frequency range can entrain EEG activity and may affect states of consciousness, although few scientific studies have been published. This study compared the effects of binaural auditory beats in the EEG beta and EEG theta/delta frequency ranges on mood and on performance of a vigilance task to investigate their effects on subjective and objective measures of arousal. Participants (n = 29) performed a 30-min visual vigilance task on three different days while listening to pink noise containing simple tones or binaural beats either in the beta range (16 and 24 Hz) or the theta/delta range (1.5 and 4 Hz). However, participants were kept blind to the presence of binaural beats to control expectation effects. Presentation of beta-frequency binaural beats yielded more correct target detections and fewer false alarms than presentation of theta/delta frequency binaural beats. In addition, the beta-frequency beats were associated with less negative mood. Results suggest that the presentation of binaural auditory beats can affect psychomotor performance and mood. This technology may have applications for the control of attention and arousal and the enhancement of human performance.
NASA Technical Reports Server (NTRS)
Knightly, W. F.
1980-01-01
Computer generated data on the performance of the cogeneration energy conversion system are presented. Performance parameters included fuel consumption and savings, capital costs, economics, and emissions of residual fired process boilers.
The effects of cognitive appraisal of stress on heart rate and task performance.
DOT National Transportation Integrated Search
1968-09-01
In aviation occupations, performance impairment under stress conditions is particularly undesirable. However, individuals may show differing amounts of impairment under stress, and the reasons for these differences are not clear. The present study ex...
NASA Technical Reports Server (NTRS)
Latta, A. F.; Bowyer, J. M.; Fujita, T.
1979-01-01
This paper presents the performance and cost of four 10-MWe advanced solar thermal electric power plants sited in various regions of the continental United States. Each region has different insolation characteristics which result in varying collector field areas, plant performance, capital costs, and energy costs. The paraboloidal dish, central receiver, cylindrical parabolic trough, and compound parabolic concentrator (CPC) comprise the advanced concepts studied. This paper contains a discussion of the regional insolation data base, a description of the solar systems' performances and costs, and a presentation of a range for the forecast cost of conventional electricity by region and nationally over the next several decades.
NASA Astrophysics Data System (ADS)
Saberimoghaddam, Ali; Bahri Rasht Abadi, Mohammad Mahdi
2018-01-01
Joule-Thomson cooling systems are commonly used in gas liquefaction. In small gas liquefiers, transient cool-down time is high. Selecting suitable conditions for cooling down process leads to decrease in time and cost. In the present work, transient thermal behavior of Joule-Thomson cooling system including counter current helically coiled tube in tube heat exchanger, expansion valve, and collector was studied using experimental tests and simulations. The experiments were performed using small gas liquefier and nitrogen gas as working fluid. The heat exchanger was thermally studied by experimental data obtained from a small gas liquefier. In addition, the simulations were performed using experimental data as variable boundary conditions. A comparison was done between presented and conventional methods. The effect of collector heat capacity and convection heat transfer coefficient inside the tubes on system performance was studied using temperature profiles along the heat exchanger.
Practical Study for the Properties of Hueckel Edge Detection Operator
NASA Astrophysics Data System (ADS)
Jabbar, Hameed M. Abdul; Hatem, Amal J.; Ameer, Inbethaq M. A. Abdul
2018-05-01
The first practical study for the Hueckel edge detection operator was presented in this research, where it is tested on standard step edge set images. A number of criteria were adopted to evaluate its practical performance, which is the accuracy in detecting the edges direction, the error in the edges location (dislocation), edges width, the calculated edge goodness criterion and the consumed execution time. These criteria were studied with the edge direction and the used disk radius of the Hueckel edge detection operator. Important notes were recorded for the performance of this operator depending on the direction of the edge and/or with the radius of the used disk. There is a variation in the performance of the operator in terms of precision in detecting of the edges direction and position. A discussion was presented for the all criteria adopted in the research.
Performance Cycle Analysis of a Two-Spool, Separate-Exhaust Turbofan With Interstage Turbine Burner
NASA Technical Reports Server (NTRS)
Liew, K. H.; Urip, E.; Yang, S. L.; Mattingly, J. D.; Marek, C. J.
2005-01-01
This paper presents the performance cycle analysis of a dual-spool, separate-exhaust turbofan engine, with an Interstage Turbine Burner serving as a secondary combustor. The ITB, which is located at the transition duct between the high- and the low-pressure turbines, is a relatively new concept for increasing specific thrust and lowering pollutant emissions in modern jet engine propulsion. A detailed performance analysis of this engine has been conducted for steady-state engine performance prediction. A code is written and is capable of predicting engine performances (i.e., thrust and thrust specific fuel consumption) at varying flight conditions and throttle settings. Two design-point engines were studied to reveal trends in performance at both full and partial throttle operations. A mission analysis is also presented to assure the advantage of saving fuel by adding ITB.
NASA Technical Reports Server (NTRS)
Abel, Irving
1997-01-01
An overview of recently completed programs in aeroelasticity and structural dynamics research at the NASA Langley Research Center is presented. Methods used to perform flutter clearance studies in the wind-tunnel on a high performance fighter are discussed. Recent advances in the use of smart structures and controls to solve aeroelastic problems, including flutter and gust response are presented. An aeroelastic models program designed to support an advanced high speed civil transport is described. An extension to transonic small disturbance theory that better predicts flows involving separation and reattachment is presented. The results of a research study to determine the effects of flexibility on the taxi and takeoff characteristics of a high speed civil transport are presented. The use of photogrammetric methods aboard Space Shuttle to measure spacecraft dynamic response is discussed. Issues associated with the jitter response of multi-payload spacecraft are discussed. Finally a Space Shuttle flight experiment that studied the control of flexible spacecraft is described.
Senko, Corwin; Belmonte, Kimberly; Yakhkind, Anastasyia
2012-09-01
Which instructor qualities do students consider most important? The answer likely depends on the student. This study attempted to trace beliefs about the most essential instructor qualities to students' academic achievement goals. The present study tested the hypothesis that students pursuing mastery goals favour instructors who stimulate and challenge them intellectually, whereas those pursuing performance goals favour instructors who present material clearly and provide clear cues about how to succeed. Participants were 157 students at a 4-year public university. Participants designed the ideal professor through a hypothetical combination of nine widely valued instructor qualities, such as enthusiasm, presentation clarity, and an interactive teaching style. The more they acquired of any one instructor quality, the less they could acquire of the others, thus compelling students to distinguish necessary qualities from desirable luxury qualities. Students' achievement goals corresponded to their views about the most essential instructor qualities. Mastery goals predicted greater demand for professors who intellectually challenge students and possess topic expertise, whereas performance goals predicted high demand for professors who present material clearly and provide cues about how to succeed in the course. The findings support emerging theorizing about how mastery and performance goals nudge students to pursue different learning agendas, with distinct consequences to their learning experience. ©2011 The British Psychological Society.
The Effects of Self-Monitoring on Safe Posture Performance
ERIC Educational Resources Information Center
Gravina, Nicole; Austin, John; Schoedtder, Lori; Loewy, Shannon
2008-01-01
The purpose of the present study was to examine the effects of self-monitoring on safe positioning of individuals performing a typing task and an assembly task using a multiple baseline design across behaviors and tasks. The study took place in an analogue office setting with seven college student participants. The dependent variable was the…
Nursery practices, seedling sizes, and field performance.
William I. Stein
1988-01-01
Highlights are presented from a large cooperative study to determine the combined effects of nursery cultural practices on the initial size and subsequent field performance of 2+0 Douglas-fir seedlings. The study involved seven sources of stock produced in three different nurseries and field plantings made over 3 years on 28 sites in southwestern Oregon. Seedbed...
Serving the Needs of Performing Arts Students: A Case Study
ERIC Educational Resources Information Center
Mayer, Jennifer
2015-01-01
The intent of this case study was to gain insight into the information needs and research behaviors of upper-division performing arts students, and how to best address those needs. This article presents findings from focus group interviews of thirty music, dance, and theater majors at the University of Wyoming in Laramie. The data revealed several…
ERIC Educational Resources Information Center
Carrera-Fernández, María Victoria; Lameiras-Fernández, María; Rodríguez-Castro, Yolanda
2018-01-01
The purpose of the present study was to analyse adolescents' perception of bullying and particularly of the ways intelligible masculinities and femininities are performed through violence in the framework of Queer Theory. We conducted a qualitative study using focus groups. The sample was composed of 93 Spanish adolescents (48 girls and 45 boys,…
The Study of Workplace Learning and Performance Competencies among Pakistani Practitioners
ERIC Educational Resources Information Center
Sherwani, Naseem Saeed
2010-01-01
The purpose of this study was to investigate Pakistani Workplace Learning and Performance (WLP) practitioners' perceptions of the importance of WLP competencies at the present time and in the next five years. The goals were to: (1) identify and characterize a profile of Pakistani WLP practitioners; (2) analyze perceptions of the current and future…
ERIC Educational Resources Information Center
Al-Ashqar, Wafaa Mohammed Ali
2017-01-01
The present study aimed to detect the level of faculty members' attitudes at public universities towards the performance appraisal process and its relationship with some variables (gender, college, scientific rank, university, teaching experience, and age). The study sample consisted of (320) faculty members of both sexes in three public…
ERIC Educational Resources Information Center
Kormos, Judit; Préfontaine, Yvonne
2017-01-01
The present mixed-methods study examined the role of learner appraisals of speech tasks in second language (L2) French fluency. Forty adult learners in a Canadian immersion program participated in the study that compared four sources of data: (1) objectively measured utterance fluency in participants' performances of three narrative tasks…
Music: Artistic Performance or a Therapeutic Tool? A Study on Differences
ERIC Educational Resources Information Center
Petersson, Gunnar; Nystrom, Maria
2011-01-01
The aim of this study is to analyze and describe how musicians who are also music therapy students separate music as artistic performance from music as a therapeutic tool. The data consist of 18 written reflections from music therapy students that were analyzed according to a phenomenographic method. The findings are presented as four…
Could Learning Outcomes of the First Course in Accounting Predict Overall Academic Performance?
ERIC Educational Resources Information Center
Alanzi, Khalid A.; Alfraih, Mishari M.
2017-01-01
Purpose: This study aims to question whether learning outcomes of the first course in accounting could predict the overall academic performance of accounting students as measured by their graduating grade point average (GPA). Design/methodology/approach The sample of the present study was drawn from accounting students who were graduated during…
Cheng, Jiao; Jin, Jing; Daly, Ian; Zhang, Yu; Wang, Bei; Wang, Xingyu; Cichocki, Andrzej
2018-02-13
Brain-computer interface (BCI) systems can allow their users to communicate with the external world by recognizing intention directly from their brain activity without the assistance of the peripheral motor nervous system. The P300-speller is one of the most widely used visual BCI applications. In previous studies, a flip stimulus (rotating the background area of the character) that was based on apparent motion, suffered from less refractory effects. However, its performance was not improved significantly. In addition, a presentation paradigm that used a "zooming" action (changing the size of the symbol) has been shown to evoke relatively higher P300 amplitudes and obtain a better BCI performance. To extend this method of stimuli presentation within a BCI and, consequently, to improve BCI performance, we present a new paradigm combining both the flip stimulus with a zooming action. This new presentation modality allowed BCI users to focus their attention more easily. We investigated whether such an action could combine the advantages of both types of stimuli presentation to bring a significant improvement in performance compared to the conventional flip stimulus. The experimental results showed that the proposed paradigm could obtain significantly higher classification accuracies and bit rates than the conventional flip paradigm (p<0.01).
Numerical and experimental investigations of micro air bearings for micro systems
NASA Astrophysics Data System (ADS)
Zhang, Qide; Shan, X. C.
2006-04-01
The paper investigated performance of air bearing system in a micro device. A parametric study is carried out. The dynamic performance of a very short journal bearing (L/D < 0.1) and thrust bearing is studied. The parameters that affect the performance of the air bearing are discussed. The optimum values of the important parameters are explored, and the stability of the thrust bearing is discussed. The prototype and test result are presented.
Congenital amusia: a short-term memory deficit for non-verbal, but not verbal sounds.
Tillmann, Barbara; Schulze, Katrin; Foxton, Jessica M
2009-12-01
Congenital amusia refers to a lifelong disorder of music processing and is linked to pitch-processing deficits. The present study investigated congenital amusics' short-term memory for tones, musical timbres and words. Sequences of five events (tones, timbres or words) were presented in pairs and participants had to indicate whether the sequences were the same or different. The performance of congenital amusics confirmed a memory deficit for tone sequences, but showed normal performance for word sequences. For timbre sequences, amusics' memory performance was impaired in comparison to matched controls. Overall timbre performance was found to be correlated with melodic contour processing (as assessed by the Montreal Battery of Evaluation of Amusia). The present findings show that amusics' deficits extend to non-verbal sound material other than pitch, in this case timbre, while not affecting memory for verbal material. This is in line with previous suggestions about the domain-specificity of congenital amusia.
Cox, Stephen J; Holden, John D
2009-01-01
Background The detection, assessment, and management of primary care poor performance raise difficult issues for all those involved. Guidance has largely focused on managing the most serious cases where patient safety is severely compromised. The management of primary care poor performance has become an increasingly important part of primary care trust (PCT) work, but its modes of presentation and prevalence are not well known. Aim To report the prevalence, presentation modes, and management of primary care poor performance cases presenting to one PCT over a 5-year period. Design of study A retrospective review of primary care poor performance cases in one district. Setting St Helens PCT administered 35 practices with 130 GPs on the performers list, caring for 190 110 patients in North West England, UK. Method Cases presenting during 2002–2007 were initially reviewed by the chair of the PCT clinical executive committee. Anonymised data were then jointly reviewed by the assessor and another experienced GP advisor. Results There were 102 individual presentations (20 per year or one every 2–3 weeks) where clinician performance raised significant cause for concern occurred over the 5-year period. These concerns related to 37 individual clinicians, a range of 1–14 per clinician (mean 2.7). Whistleblowing by professional colleagues on 43 occasions was the most common presentation, of which 26 were from GPs about GPs. Patient complaints (18) were the second most common presentation. Twenty-seven clinicians were GPs, of whom the General Medical Council (GMC) were notified or involved in 13 cases. Clinicians were supported locally, and remedying was exclusively locally managed in 14 cases, and shared with an external organisation (such as the GMC or deanery) in another 12. Conclusion Professional whistleblowing and patient complaints were the most common sources of presentation. Effective PCT teams are needed to manage clinicians whose performance gives cause for concern. Sufficient resources and both formal and informal ways of reporting concerns are essential. PMID:19401017
Memory for Self-Performed Actions in Individuals with Asperger Syndrome
Zalla, Tiziana; Daprati, Elena; Sav, Anca-Maria; Chaste, Pauline; Nico, Daniele; Leboyer, Marion
2010-01-01
Memory for action is enhanced if individuals are allowed to perform the corresponding movements, compared to when they simply listen to them (enactment effect). Previous studies have shown that individuals with Autism Spectrum Disorders (ASD) have difficulties with processes involving the self, such as autobiographical memories and self performed actions. The present study aimed at assessing memory for action in Asperger Syndrome (AS). We investigated whether adults with AS would benefit from the enactment effect when recalling a list of previously performed items vs. items that were only visually and verbally experienced through three experimental tasks (Free Recall, Old/New Recognition and Source Memory). The results showed that while performance on Recognition and Source Memory tasks was preserved in individuals with AS, the enactment effect for self-performed actions was not consistently present, as revealed by the lower number of performed actions being recalled on the Free Recall test, as compared to adults with typical development. Subtle difficulties in encoding specific motor and proprioceptive signals during action execution in individuals with AS might affect retrieval of relevant personal episodic information. These disturbances might be associated to an impaired action monitoring system. PMID:20967277
Memory for self-performed actions in individuals with Asperger syndrome.
Zalla, Tiziana; Daprati, Elena; Sav, Anca-Maria; Chaste, Pauline; Nico, Daniele; Leboyer, Marion
2010-10-12
Memory for action is enhanced if individuals are allowed to perform the corresponding movements, compared to when they simply listen to them (enactment effect). Previous studies have shown that individuals with Autism Spectrum Disorders (ASD) have difficulties with processes involving the self, such as autobiographical memories and self performed actions. The present study aimed at assessing memory for action in Asperger Syndrome (AS). We investigated whether adults with AS would benefit from the enactment effect when recalling a list of previously performed items vs. items that were only visually and verbally experienced through three experimental tasks (Free Recall, Old/New Recognition and Source Memory). The results showed that while performance on Recognition and Source Memory tasks was preserved in individuals with AS, the enactment effect for self-performed actions was not consistently present, as revealed by the lower number of performed actions being recalled on the Free Recall test, as compared to adults with typical development. Subtle difficulties in encoding specific motor and proprioceptive signals during action execution in individuals with AS might affect retrieval of relevant personal episodic information. These disturbances might be associated to an impaired action monitoring system.
St-Pierre, Marie-Claude Dion; Avalos Ramirez, Antonio; Heitz, Michèle
2009-05-01
This paper presents a study on the biofiltration of styrene by using two inorganic filtering materials. The effects of styrene inlet load and nitrogen concentration present in the nutrient solution on biofilter performance were studied. The styrene inlet concentration was varied from 65 to 1115 parts per million by volume (ppmv), whereas the contaminated airflow rate was fixed at 1 m3/hr. The nitrogen concentration in nutrient solution was varied from 1 to 4 gN/L. The maximum elimination capacity obtained was 105 g/m3-hr, which corresponded to a removal efficiency of 80% for a styrene inlet load of 130 g/m3-hr. This study shows that the nitrogen content in the nutrient solution affects the removal rate of styrene, with an optimal nitrogen concentration of 3 gN/L. The performance comparison between two different inorganic bed types was undertaken and a comparative study on biofiltration of two aromatic compounds, styrene and toluene, is also presented.
Markovska-Simoska, S; Pop-Jordanova, N
2009-07-01
(Full text is available at http://www.manu.edu.mk/prilozi). Continous Performance Tests (CPTs) form a group of paradigms for the evaluation of attention and, to a lesser degree, the response inhibition (or disinhibition) component of executive control. The object of this study was to compare performance on a CPT using both visual and emotional tasks in 46 normal adult subjects. In particular, it was to examine the effects of the type of task (VCPT or ECPT), sequence of presentation, and gender/age influence on performance as measured errors of omission, errors of commission, reaction time and variation of reaction time. From the results we can assume that there are significantly worse performance parameters for ECPT than VCPT tasks, with a probable explanation of the influence of emotional stimuli on attention and information-processing and no significant effect of order of presentation and gender on performance. Significant differences with more omission errors for older groups were obtained, showing better attention in younger subjects. Key words: VCPT, ECPT, omission errors, commission errors, reaction time, variation of reaction time, normal adults.
Implementation of the qualities of radiodiagnostic: mammography
NASA Astrophysics Data System (ADS)
Pacífico, L. C.; Magalhães, L. A. G.; Peixoto, J. G. P.; Fernandes, E.
2018-03-01
The objective of the present study was to evaluate the expanded uncertainty of the mammographic calibration process and present the result of the internal audit performed at the Laboratory of Radiological Sciences (LCR). The qualities of the mammographic beans that are references in the LCR, comprises two irradiation conditions: no-attenuated beam and attenuated beam. Both had satisfactory results, with an expanded uncertainty equals 2,1%. The internal audit was performed, and the degree of accordance with the ISO/IEC 17025 was evaluated. The result of the internal audit was satisfactory. We conclude that LCR can perform calibrations on mammography qualities for end users.
Davis, Kelly D; Winsler, Adam; Middleton, Michael
2006-06-01
In the present study, the authors examined college students' (N= 136) perceptions of the provision of extrinsic rewards given by parents and teachers for academic performance from elementary school through high school. They also examined the relations between reward history and present student motivational orientation. External rewards for students' grades were common at all levels of schooling. Reward history related significantly to students' motivational orientation and performance in college, and these relations were generally stronger for boys than for girls. The authors discuss implications of these findings.
Understanding Eating Disorders in Elite Gymnastics: Ethical and Conceptual Challenges.
Tan, Jacinta Oon Ai; Calitri, Raff; Bloodworth, Andrew; McNamee, Michael J
2016-04-01
Eating disorders and disordered eating are more common in high performance sports than the general population, and particularly so in high performance aesthetic sports. This paper presents some of the conceptual difficulties in understanding and diagnosing eating disorders in high performance gymnasts. It presents qualitative and quantitative data from a study designed to ascertain the pattern of eating disorder symptoms, depressive symptoms and levels of self-esteem among national and international level gymnasts from the UK in the gymnastic disciplines of sport acrobatics, tumbling, and rhythmic gymnastics. Copyright © 2016 Elsevier Inc. All rights reserved.
Ontology Performance Profiling and Model Examination: First Steps
NASA Astrophysics Data System (ADS)
Wang, Taowei David; Parsia, Bijan
"[Reasoner] performance can be scary, so much so, that we cannot deploy the technology in our products." - Michael Shepard. What are typical OWL users to do when their favorite reasoner never seems to return? In this paper, we present our first steps considering this problem. We describe the challenges and our approach, and present a prototype tool to help users identify reasoner performance bottlenecks with respect to their ontologies. We then describe 4 case studies on synthetic and real-world ontologies. While the anecdotal evidence suggests that the service can be useful for both ontology developers and reasoner implementors, much more is desired.
Total Absorption Study of Beta Decays Relevant for Nuclear Applications and Nuclear Structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Algora, A.; Valencia, E.; Tain, J. L.
2014-06-01
We present an overview of our activities related to the study of the beta decay of neutron rich nuclei relevant for nuclear applications. Recent results of the study of the beta decay of Br using a new segmented total absorption spectrometer are presented. Our measurements were performed at the IGISOL facility using trap-assisted total absorption spectroscopy.
ERIC Educational Resources Information Center
Kobayashi, Masaki
2016-01-01
The present study provides an in-depth, longitudinal account of an undergraduate student's L2 discourse socialization in an academic exchange program in Canada. By invoking Rogoff's (1995) notion of participatory appropriation, this qualitative case study examined an L2 student's task-related strategies and performance as they evolved over time in…
Experimental study of PAM-4, CAP-16, and DMT for 100 Gb/s short reach optical transmission systems.
Zhong, Kangping; Zhou, Xian; Gui, Tao; Tao, Li; Gao, Yuliang; Chen, Wei; Man, Jiangwei; Zeng, Li; Lau, Alan Pak Tao; Lu, Chao
2015-01-26
Advanced modulation formats combined with digital signal processing and direct detection is a promising way to realize high capacity, low cost and power efficient short reach optical transmission system. In this paper, we present a detailed investigation on the performance of three advanced modulation formats for 100 Gb/s short reach transmission system. They are PAM-4, CAP-16 and DMT. The detailed digital signal processing required for each modulation format is presented. Comprehensive simulations are carried out to evaluate the performance of each modulation format in terms of received optical power, transmitter bandwidth, relative intensity noise and thermal noise. The performance of each modulation format is also experimentally studied. To the best of our knowledge, we report the first demonstration of a 112 Gb/s transmission over 10km of SSMF employing single band CAP-16 with EML. Finally, a comparison of computational complexity of DSP for the three formats is presented.
Weiner, Saul J; Schwartz, Alan; Yudkowsky, Rachel; Schiff, Gordon D; Weaver, Frances M; Goldberg, Julie; Weiss, Kevin B
2007-01-01
Clinical decision making requires 2 distinct cognitive skills: the ability to classify patients' conditions into diagnostic and management categories that permit the application of research evidence and the ability to individualize or-more specifically-to contextualize care for patients whose circumstances and needs require variation from the standard approach to care. The purpose of this study was to develop and test a methodology for measuring physicians' performance at contextualizing care and compare it to their performance at planning biomedically appropriate care. First, the authors drafted 3 cases, each with 4 variations, 3 of which are embedded with biomedical and/or contextual information that is essential to planning care. Once the cases were validated as instruments for assessing physician performance, 54 internal medicine residents were then presented with opportunities to make these preidentified biomedical or contextual errors, and data were collected on information elicitation and error making. The case validation process was successful in that, in the final iteration, the physicians who received the contextual variant of cases proposed an alternate plan of care to those who received the baseline variant 100% of the time. The subsequent piloting of these validated cases unmasked previously unmeasured differences in physician performance at contextualizing care. The findings, which reflect the performance characteristics of the study population, are presented. This pilot study demonstrates a methodology for measuring physician performance at contextualizing care and illustrates the contribution of such information to an overall assessment of physician practice.
The effect of solar array degradation on electric propulsion spacecraft performance.
NASA Technical Reports Server (NTRS)
Sauer, C. G., Jr.; Bourke, R. D.
1972-01-01
Current estimates of solar-electric-propulsion spacecraft performance are based upon a solar-array output power which is degraded by approximately 10-13% to account for possible losses caused by proton, electron and micrometeorite damage. Past studies have used a worst case analysis in which the maximum degradation was taken to occur at the beginning of the mission. This paper presents a comparison of mission studies using a hypothetical exponential decrease in power with time, with those using a sudden degradation of solar power. These comparisons indicate that the performance gain by using a time varying degradation during the mission is quite small for outbound missions in the solar system. In addition an indication of the power allocation strategy to be followed during a mission is presented.
NASA Astrophysics Data System (ADS)
Valente, Diego; Savkar, Amit; Mokaya, Fridah; Wells, James
The Force Concept Inventory (FCI) has been analyzed and studied in various ways with regards to students' understanding of basic physics concepts. We present normalized learning gains and effect size calculations of FCI scores, taken in the context of large-scale classes in a 4-year public university and course instruction that incorporates elements of Just-In-Time teaching and active learning components. In addition, we will present here a novel way of using FCI pre- and post-test as a predictor of students' performance on midterm and final exams. Utilizing a taxonomy table of physics concepts, we will look at student performance broken down by topic, while also examining possible correlations between FCI post-test scores and other course assessments. College of Liberal Arts and Sciences (CLAS), UConn.
Behavioral relevance of gamma-band activity for short-term memory-based auditory decision-making.
Kaiser, Jochen; Heidegger, Tonio; Lutzenberger, Werner
2008-06-01
Oscillatory activity in the gamma-band range has been established as a correlate of cognitive processes, including perception, attention and memory. Only a few studies, however, have provided evidence for an association between gamma-band activity (GBA) and measures of behavioral performance. Here we focused on the comparison between sample and test stimuli S1 and S2 during an auditory spatial short-term memory task. Applying statistical probability mapping to magnetoencephalographic recordings from 28 human subjects, we identified GBA components distinguishing nonidentical from identical S1-S2 pairs. This activity was found at frequencies between 65 and 90 Hz and was localized over posterior cortical regions contralateral to the hemifield in which the stimuli were presented. The 10 best task performers showed higher amplitudes of this GBA component than the 10 worst performers. This group difference was most pronounced between about 150 and 300 ms after stimulus onset. Apparently the decision about whether test stimuli matched the stored representation of previously presented sample sounds relied partly on the oscillatory activation of networks representing differences between both stimuli. This result could be replicated by reanalyzing the combined data from two previous studies assessing short-term memory for sound duration and sound lateralization, respectively. Similarly to our main study, GBA amplitudes to nonmatching vs. matching S1-S2 pairs were higher in good performers than poor performers. The present findings demonstrate the behavioral relevance of GBA.
Connery, Amy K; Peterson, Robin L; Baker, David A; Kirkwood, Michael W
2016-05-01
In recent years, pediatric practitioners have increasingly recognized the importance of objectively measuring performance validity during clinical assessments. Yet, no studies have examined the impact of neuropsychological consultation when invalid performance has been identified in pediatric populations and little published guidance exists for clinical management. Here we provide a conceptual model for providing feedback after noncredible performance has been detected. In a pilot study, we examine caregiver satisfaction and postconcussive symptoms following provision of this feedback for patients seen through our concussion program. Participants (N = 70) were 8-17-year-olds with a history of mild traumatic brain injury who underwent an abbreviated neuropsychological evaluation between 2 and 12 months post-injury. We examined postconcussive symptom reduction and caregiver satisfaction after neuropsychological evaluation between groups of patients who were determined to have provided noncredible effort (n = 9) and those for whom no validity concerns were present (n = 61). We found similarly high levels of caregiver satisfaction between groups and greater reduction in self-reported symptoms after feedback was provided using the model with children with noncredible presentations compared to those with credible presentations. The current study lends preliminary support to the idea that the identification and communication of invalid performance can be a beneficial clinical intervention that promotes high levels of caregiver satisfaction and a reduction in self-reported and caregiver-reported symptoms.
Shimoda, Kaori; Moriguchi, Yoshiya; Tsuchiya, Kenji; Katsuyama, Shiori; Tozato, Fusae
2014-01-01
Individuals have a preferred pace at which they perform voluntary repetitive movements. Previous studies have reported that greater activation of the prefrontal cortex was observed during self-initiated movements than during externally triggered movements. The purpose of the present study is to compare the activation of the prefrontal cortex induced when the subjects performed a peg-board task at their preferred slow pace (PSP, the self-initiated condition) with that induced when they performed the same task at metronome slow pace (MSP, the externally triggered condition) using functional near-infrared spectroscopy. Healthy subjects performed the task while sitting in a chair. By assessing the activated channels individually, we confirmed that all of the prefrontal regions of interest were activated by both tasks. In the second-level analyses, we found that the activation detected in the frontopolar cortex (FPPFC; Brodmann area 10) was higher during the PSP task than during the MSP task. The FPPFC is known to be at the top of prefrontal hierarchy, and specifically involved in evaluating self-generated information. In addition, the FPPFC plays a role in coordinating lateral prefrontal cortex. In the present study, the subjects evaluated and managed the internally generated PSP by coordinating the activity of other lower level prefrontal regions.
Body composition and size in sprint athletes.
Barbieri, Davide; Zaccagni, Luciana; Babić, Vesna; Rakovac, Marija; Mišigoj-Duraković, Marjeta; Gualdi-Russo, Emanuela
2017-09-01
The aims of the present study were to assess competitive sprinters' body size and composition and to determine their impact on performance. Ninety-eight competitive male sprinters (100 m) participated in this cross-sectional study. A series of measurements was directly taken and data on muscular strength and power tests were self-reported. Body composition was assessed by skinfold method and somatotype was calculated by the Heath-Carter anthropometric method. Sprinters were classified into three groups depending on their personal best time and comparisons were performed between the athletes in the top and in the bottom tertiles. Relationships between anthropometric traits and performance were assessed by Pearson's correlation coefficients. Top sprinters had significantly greater body mass index, relaxed and contracted upper arm girths, thigh and calf girths, fat free mass and fat free mass index, and lower ectomorphy than the lowest tertile. Strength and power were significantly higher. Personal best time was significantly correlated with several anthropometric traits and indices of lean body mass. Body size, composition and somatotype differ between performance levels in speed running. Being less ectomorphic, with a greater fat free mass and strength, can explain significant differences in sprinting performances. The results presented in this study provide a point of reference about sprinter characteristics, which can help coaches and sport scientists to improve sprinter performance.
A unified method for evaluating real-time computer controllers: A case study. [aircraft control
NASA Technical Reports Server (NTRS)
Shin, K. G.; Krishna, C. M.; Lee, Y. H.
1982-01-01
A real time control system consists of a synergistic pair, that is, a controlled process and a controller computer. Performance measures for real time controller computers are defined on the basis of the nature of this synergistic pair. A case study of a typical critical controlled process is presented in the context of new performance measures that express the performance of both controlled processes and real time controllers (taken as a unit) on the basis of a single variable: controller response time. Controller response time is a function of current system state, system failure rate, electrical and/or magnetic interference, etc., and is therefore a random variable. Control overhead is expressed as a monotonically nondecreasing function of the response time and the system suffers catastrophic failure, or dynamic failure, if the response time for a control task exceeds the corresponding system hard deadline, if any. A rigorous probabilistic approach is used to estimate the performance measures. The controlled process chosen for study is an aircraft in the final stages of descent, just prior to landing. First, the performance measures for the controller are presented. Secondly, control algorithms for solving the landing problem are discussed and finally the impact of the performance measures on the problem is analyzed.
Eksborg, Staffan
2013-01-01
Pharmacokinetic studies are important for optimizing of drug dosing, but requires proper validation of the used pharmacokinetic procedures. However, simple and reliable statistical methods suitable for evaluation of the predictive performance of pharmacokinetic analysis are essentially lacking. The aim of the present study was to construct and evaluate a graphic procedure for quantification of predictive performance of individual and population pharmacokinetic compartment analysis. Original data from previously published pharmacokinetic compartment analyses after intravenous, oral, and epidural administration, and digitized data, obtained from published scatter plots of observed vs predicted drug concentrations from population pharmacokinetic studies using the NPEM algorithm and NONMEM computer program and Bayesian forecasting procedures, were used for estimating the predictive performance according to the proposed graphical method and by the method of Sheiner and Beal. The graphical plot proposed in the present paper proved to be a useful tool for evaluation of predictive performance of both individual and population compartment pharmacokinetic analysis. The proposed method is simple to use and gives valuable information concerning time- and concentration-dependent inaccuracies that might occur in individual and population pharmacokinetic compartment analysis. Predictive performance can be quantified by the fraction of concentration ratios within arbitrarily specified ranges, e.g. within the range 0.8-1.2.
ERIC Educational Resources Information Center
Murphy, Karen; Barry, Shane
2016-01-01
Presentation feedback can be limited in its feed-forward value, as students do not have their actual presentation available for review whilst reflecting upon the feedback. This study reports on students' perceptions of the learning and feed-forward value of an oral presentation assessment. Students self-marked their performance immediately after…
Evaluation of an Integrated Read-Out Layer Prototype
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abu-Ajamieh, Fayez
2011-07-01
This thesis presents evaluation results of an Integrated Read-out Layer (IRL), a proposed concept in scintillator-based calorimetry intended to meet the exceptional calorimetric requirements of the envisaged International Linear Collider (ILC). This study presents a full characterization of the prototype IRL, including exploration of relevant parameters, calibration performance, and the uniformity of response. The study represents proof of the IRL concept. Finally, proposed design enhancements are presented.
Evaluation of an Integrated Read-Out Layer Prototype
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abu-Ajamieh, Fayez; /NIU
2011-08-18
This thesis presents evaluation results of an Integrated Read-out Layer (IRL), a proposed concept in scintillator-based calorimetry intended to meet the exceptional calorimetric requirements of the envisaged International Linear Collider (ILC). This study presents a full characterization of the prototype IRL, including exploration of relevant parameters, calibration performance, and the uniformity of response. The study represents proof of the IRL concept. Finally, proposed design enhancements are presented.
Example-Based Learning: Effects of Model Expertise in Relation to Student Expertise
ERIC Educational Resources Information Center
Boekhout, Paul; van Gog, Tamara; van de Wiel, Margje W. J.; Gerards-Last, Dorien; Geraets, Jacques
2010-01-01
Background: Worked examples are very effective for novice learners. They typically present a written-out ideal (didactical) solution for learners to study. Aims: This study used worked examples of patient history taking in physiotherapy that presented a "non"-didactical solution (i.e., based on actual performance). The effects of model expertise…
Effects of Presentation Mode and Computer Familiarity on Summarization of Extended Texts
ERIC Educational Resources Information Center
Yu, Guoxing
2010-01-01
Comparability studies on computer- and paper-based reading tests have focused on short texts and selected-response items via almost exclusively statistical modeling of test performance. The psychological effects of presentation mode and computer familiarity on individual students are under-researched. In this study, 157 students read extended…
D-21B RBCC Modification Feasibility Study
NASA Technical Reports Server (NTRS)
1999-01-01
This report presents a feasibility study on the modifications required to re-engine the Lockheed D-21 Drone for use as a NASA RBCC engine. An introduction, background information, engine configuration and performance, propulsion system integration, loads/thermal analysis, avionics/systems, flight test results, costs and work schedule, and some conclusions are presented.
Excavation/Fill/Soil Disturbance, Self-Study #31419
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grogin, Phillip W.
This course, Excavation/Fill/Soil Disturbance Self-Study (#31419), presents an overview of the hazards, controls, and requirements that affect safe excavations at Los Alamos National Laboratory (LANL). An overview of the LANL excavation/fill/soil disturbance permit (EXID permit) approval process is also presented, along with potholing requirements for planning and performing excavations at LANL.
Preliminary subsystem designs for the Assured Crew Return Vehicle (ACRV), volume 1
NASA Technical Reports Server (NTRS)
1990-01-01
A series of design studies is presented concerning the Assured Crew Return Vehicle (ACRV) for Space Station Freedom. Four alternate designs are presented for the ACRV braking and landing system. Options presented include: ballistic and lifting body reentries; the use of high-lift, high-payload aerodynamic decelerators, as well as conventional parachutes; landing systems designed for water landings, land landings, or both; and an aerial recovery system. All four design options presented combine some or all of the above attributes, and all meet performance requirements established by the ACRV Program Office. Two studies of ACRV growth options are also presented. Use of the ACRV or a similarly designed vehicle in several roles for possible future space missions is discussed, along with the required changes to a basic ACRV to allow it to perform these missions optimally. The outcome of these studies is a set of recommendations to the ACRV Program Office describing the vehicle characteristics of the basic ACRV which lend themselves most readily to be adapted for use in other missions. Finally, the impacts on the design of the ACRV due to its role as a medical emergency vehicle were studied and are presented. The use of the ACRV in this manner will impact its shape, internal configuration, and equipment.
Centrifugal slurry pump wear and hydraulic studies. Phase II report. Experimental studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mistry, D.; Cooper, P.; Biswas, C.
1983-01-01
This report describes the work performed by Ingersoll-Rand Research, Inc., under Phase II, Experimental Studies for the contract entitled, Centrifugal Slurry Pump Wear and Hydraulic Studies. This work was carried out for the US Department of Energy under Contract No. DE-AC-82PC50035. The basic development approach pursued this phase is presented, followed by a discussion on wear relationships. The analysis, which resulted in the development of a mathematical wear model relating pump life to some of the key design and operating parameters, is presented. The results, observations, and conclusions of the experimental investigation on small scale pumps that led to themore » selected design features for the prototype pump are discussed. The material investigation was performed at IRRI, ORNL and Battelle. The rationale for selecting the materials for testing, the test methods and apparatus used, and the results obtained are presented followed by a discussion on materials for a prototype pump. In addition, the prototype pump test facility description, as well as the related design and equipment details, are presented. 20 references, 53 figures, 13 tables.« less
CPMIP: measurements of real computational performance of Earth system models in CMIP6
NASA Astrophysics Data System (ADS)
Balaji, Venkatramani; Maisonnave, Eric; Zadeh, Niki; Lawrence, Bryan N.; Biercamp, Joachim; Fladrich, Uwe; Aloisio, Giovanni; Benson, Rusty; Caubel, Arnaud; Durachta, Jeffrey; Foujols, Marie-Alice; Lister, Grenville; Mocavero, Silvia; Underwood, Seth; Wright, Garrett
2017-01-01
A climate model represents a multitude of processes on a variety of timescales and space scales: a canonical example of multi-physics multi-scale modeling. The underlying climate system is physically characterized by sensitive dependence on initial conditions, and natural stochastic variability, so very long integrations are needed to extract signals of climate change. Algorithms generally possess weak scaling and can be I/O and/or memory-bound. Such weak-scaling, I/O, and memory-bound multi-physics codes present particular challenges to computational performance. Traditional metrics of computational efficiency such as performance counters and scaling curves do not tell us enough about real sustained performance from climate models on different machines. They also do not provide a satisfactory basis for comparative information across models. codes present particular challenges to computational performance. We introduce a set of metrics that can be used for the study of computational performance of climate (and Earth system) models. These measures do not require specialized software or specific hardware counters, and should be accessible to anyone. They are independent of platform and underlying parallel programming models. We show how these metrics can be used to measure actually attained performance of Earth system models on different machines, and identify the most fruitful areas of research and development for performance engineering. codes present particular challenges to computational performance. We present results for these measures for a diverse suite of models from several modeling centers, and propose to use these measures as a basis for a CPMIP, a computational performance model intercomparison project (MIP).
Boerebach, Benjamin C. M.; Lombarts, Kiki M. J. M. H.; Scherpbier, Albert J. J.; Arah, Onyebuchi A.
2013-01-01
Background In fledgling areas of research, evidence supporting causal assumptions is often scarce due to the small number of empirical studies conducted. In many studies it remains unclear what impact explicit and implicit causal assumptions have on the research findings; only the primary assumptions of the researchers are often presented. This is particularly true for research on the effect of faculty’s teaching performance on their role modeling. Therefore, there is a need for robust frameworks and methods for transparent formal presentation of the underlying causal assumptions used in assessing the causal effects of teaching performance on role modeling. This study explores the effects of different (plausible) causal assumptions on research outcomes. Methods This study revisits a previously published study about the influence of faculty’s teaching performance on their role modeling (as teacher-supervisor, physician and person). We drew eight directed acyclic graphs (DAGs) to visually represent different plausible causal relationships between the variables under study. These DAGs were subsequently translated into corresponding statistical models, and regression analyses were performed to estimate the associations between teaching performance and role modeling. Results The different causal models were compatible with major differences in the magnitude of the relationship between faculty’s teaching performance and their role modeling. Odds ratios for the associations between teaching performance and the three role model types ranged from 31.1 to 73.6 for the teacher-supervisor role, from 3.7 to 15.5 for the physician role, and from 2.8 to 13.8 for the person role. Conclusions Different sets of assumptions about causal relationships in role modeling research can be visually depicted using DAGs, which are then used to guide both statistical analysis and interpretation of results. Since study conclusions can be sensitive to different causal assumptions, results should be interpreted in the light of causal assumptions made in each study. PMID:23936020
Temporal Dynamics of Visual Attention Measured with Event-Related Potentials
Kashiwase, Yoshiyuki; Matsumiya, Kazumichi; Kuriki, Ichiro; Shioiri, Satoshi
2013-01-01
How attentional modulation on brain activities determines behavioral performance has been one of the most important issues in cognitive neuroscience. This issue has been addressed by comparing the temporal relationship between attentional modulations on neural activities and behavior. Our previous study measured the time course of attention with amplitude and phase coherence of steady-state visual evoked potential (SSVEP) and found that the modulation latency of phase coherence rather than that of amplitude was consistent with the latency of behavioral performance. In this study, as a complementary report, we compared the time course of visual attention shift measured by event-related potentials (ERPs) with that by target detection task. We developed a novel technique to compare ERPs with behavioral results and analyzed the EEG data in our previous study. Two sets of flickering stimulus at different frequencies were presented in the left and right visual hemifields, and a target or distracter pattern was presented randomly at various moments after an attention-cue presentation. The observers were asked to detect targets on the attended stimulus after the cue. We found that two ERP components, P300 and N2pc, were elicited by the target presented at the attended location. Time-course analyses revealed that attentional modulation of the P300 and N2pc amplitudes increased gradually until reaching a maximum and lasted at least 1.5 s after the cue onset, which is similar to the temporal dynamics of behavioral performance. However, attentional modulation of these ERP components started later than that of behavioral performance. Rather, the time course of attentional modulation of behavioral performance was more closely associated with that of the concurrently recorded SSVEPs analyzed. These results suggest that neural activities reflected not by either the P300 or N2pc, but by the SSVEPs, are the source of attentional modulation of behavioral performance. PMID:23976966
Transit Bus Fuel Economy and Performance Simulation
DOT National Transportation Integrated Search
1984-01-01
This report presents the results of bus simulation studies to determine the effects of various design and operating parameters on bus fuel economy and performance. The bus components are first described in terms of how they are modeled. Then a variat...
Deep Space Spaceflight: The Challenge of Crew Performance in Autonomous Operations
NASA Astrophysics Data System (ADS)
Thaxton, S. S.; Williams, T. J.; Norsk, P.; Zwart, S.; Crucian, B.; Antonsen, E. L.
2018-02-01
Distance from Earth and limited communications in future missions will increase the demands for crew autonomy and dependence on automation, and Deep Space Gateway presents an opportunity to study the impacts of these increased demands on human performance.
Complex monitoring performance and the coronary-prone Type A behavior pattern.
DOT National Transportation Integrated Search
1986-03-01
The present study examined the possible relationship of the coronary-prone Type A behavior pattern to performance of a complex monitoring task. The task was designed to functionally simulate the general task characteristics of future, highly automate...
DOT National Transportation Integrated Search
1983-09-01
The present study employed auditory startle to simulate the principal components (unexpectedness, fear, and physiological arousal) that are common to many types of sudden emergencies and compared performance recovery following startle with recovery f...
DOT National Transportation Integrated Search
1980-10-01
The present study examined a variety of possible predictors of complex monitoring performance. The criterion task was designed to resemble that of a highly automated air traffic control radar system containing computer-generated alphanumeric displays...
Holden, Richard J.; Valdez, Rupa S.; Schubert, Christiane C.; Thompson, Morgan J.; Hundt, Ann S.
2017-01-01
Human factors/ergonomics recognizes work as embedded in and shaped by levels of social, physical, and organizational context. This study investigates the contextual or macroergonomic factors present in the health-related work performed by patients. We performed a secondary content analysis of findings from three studies of the work of chronically ill patients and their informal caregivers. Our resulting consolidated macroergonomic patient work system model identifies seventeen factors across physical, social, and organizational domains and household and community levels. These factors are illustrated with examples from the three studies and discussed as having positive, negative, or varying effects on health and health behavior. We present three brief case studies to illustrate how macroergonomic factors combine across domains and levels to shape performance in expected and unexpected ways. Findings demonstrate not only the importance of context for patients’ health-related activities but also specific factors to consider in future research, design, and policy efforts. PMID:27164171
Menon, Samir; Zhu, Jack; Goyal, Deeksha; Khatib, Oussama
2017-07-01
Haptic interfaces compatible with functional magnetic resonance imaging (Haptic fMRI) promise to enable rich motor neuroscience experiments that study how humans perform complex manipulation tasks. Here, we present a large-scale study (176 scans runs, 33 scan sessions) that characterizes the reliability and performance of one such electromagnetically actuated device, Haptic fMRI Interface 3 (HFI-3). We outline engineering advances that ensured HFI-3 did not interfere with fMRI measurements. Observed fMRI temporal noise levels with HFI-3 operating were at the fMRI baseline (0.8% noise to signal). We also present results from HFI-3 experiments demonstrating that high resolution fMRI can be used to study spatio-temporal patterns of fMRI blood oxygenation dependent (BOLD) activation. These experiments include motor planning, goal-directed reaching, and visually-guided force control. Observed fMRI responses are consistent with existing literature, which supports Haptic fMRI's effectiveness at studying the brain's motor regions.
An Exploration of the Gap between Highest and Lowest Ability Readers across 20 Countries
ERIC Educational Resources Information Center
Alivernini, Fabio
2013-01-01
The aim of the present study, based on data from 20 countries, is to identify the pattern of variables (at country, school and student levels), which are typical of students performing below the low international benchmark compared to students performing at the advanced performance benchmark, in the Progress in International Reading Literacy Study…
ERIC Educational Resources Information Center
Egeland, Jens; Kovalik-Gran, Iwona
2010-01-01
Objective: Continuous performance tests are known to typically measure sustained attention but usually also yield parameters that potentially measure other subprocesses of attention. The aim of the present study was to test the factor structure of the Conners's Continuous Performance Test (CCPT) in a heterogeneous clinical sample consisting of…
Competition and Performance: More Facts, More Understanding? Comment on Murayama and Elliot (2012)
ERIC Educational Resources Information Center
Johnson, David W.; Johnson, Roger T.; Roseth, Cary J.
2012-01-01
Murayama and Elliot (2012) made a significant contribution to the literature on competition by presenting the results of 2 meta-analyses and 3 primary studies on the relation between competition and performance. Murayama and Elliot established that in general, there is no relationship between competition and performance. They then made the case…
The Use of Performance Feedback in School Improvement in Louisiana
ERIC Educational Resources Information Center
Schildkamp, Kim; Visscher, Adrie
2010-01-01
Although school performance feedback is available in schools all over the world, there is a dearth of information about the use made of feedback and about the effects of its use. This paper presents case study research into the use of school performance feedback and its perceived effects. All schools used the feedback in writing school improvement…
ERIC Educational Resources Information Center
West, Katara K.; Mathews, Brittany L.; Kerns, Kathryn A.
2013-01-01
Although mother-child attachment has been shown to predict cognitive performance, there has been a lack of attention to the mediating mechanisms that explain these associations. In the present study, we investigated relations of early mother-child attachment and cognitive performance in middle childhood (the latter in terms of both academic…
ERIC Educational Resources Information Center
Burtscher, Michael J.; Kolbe, Michaela; Wacker, Johannes; Manser, Tanja
2011-01-01
In the present study, we investigated how two team mental model properties (similarity vs. accuracy) and two forms of monitoring behavior (team vs. systems) interacted to predict team performance in anesthesia. In particular, we were interested in whether the relationship between monitoring behavior and team performance was moderated by team…
Findings from the School-Based Theatrical Performance "Walk in Our Shoes." Research Report
ERIC Educational Resources Information Center
Wong, Eunice C.; Cerully, Jennifer L.; Collings, Rebecca L.; Roth, Elizabeth
2014-01-01
The study presented in this report evaluates the effects of a school-based theatrical performance "Walk In Our Shoes" on a group of predominantly Latino youth in Santa Barbara County, California. The performance follows the lives of four (fictional) high school students and introduces their various experiences with both mental health…
ERIC Educational Resources Information Center
Zimmermann, Judith; Brodersen, Kay H.; Heinimann, Hans R.; Buhmann, Joachim M.
2015-01-01
The graduate admissions process is crucial for controlling the quality of higher education, yet, rules-of-thumb and domain-specific experiences often dominate evidence-based approaches. The goal of the present study is to dissect the predictive power of undergraduate performance indicators and their aggregates. We analyze 81 variables in 171…
ERIC Educational Resources Information Center
Mitchell, Alison; Baron, Lauren; Macaruso, Paul
2018-01-01
Screening and monitoring student reading progress can be costly and time consuming. Assessment embedded within the context of online instructional programs can capture ongoing student performance data while limiting testing time outside of instruction. This paper presents two studies that examined the validity of using performance measures from a…
Scale Issues in Air Quality Modeling
This presentation reviews past model evaluation studies investigating the impact of horizontal grid spacing on model performance. It also presents several examples of using a spectral decomposition technique to separate the forcings from processes operating on different time scal...
AASHO correlation study : final report.
DOT National Transportation Integrated Search
1971-09-01
The application of the design concepts developed at the AASHO road test to Louisiana in-service pavements are presented. In order to correlate the level of performance determined at the road test with that of Louisiana pavements, present serviceabili...
1984-09-10
0") AD STUDIES ON THE INHALATION TOXICITY CO• OF DYES PRESENT IN COLORED Ln SMOKE MUNIlIONS U FINAL REPORT FOR PHASE III STUDIES : SFOUR- ELK...3 RECIIEPIT’S CATA6.0G NUMBE.• 4. TITLE (and ,ubiltI.e) S. TYPE OF REPORT & PERIOD COygC r., Studies on the Inhalation Toxicity of Dyes Final: Phase...III Present in Colored Smoke Munitions. Final Report Fh for Phase 111 Studies : FoLr-Week Inhalation G. PERFORMING ORO. REPORT N,’,ER Exposures of Rats
Nakagawa, Yuko; Inoue, Akiomi; Kawakami, Norito; Tsuno, Kanami; Tomioka, Kimiko; Nakanishi, Mayuko; Mafune, Kosuke; Hiro, Hisanori
2015-01-01
The aim of the present study was to investigate the association of one-year change in organizational justice (i.e., procedural justice and interactional justice) with job performance in Japanese employees. This study surveyed 425 men and 683 women from a manufacturing company in Japan. Self-administered questionnaires, including the Organizational Justice Questionnaire (OJQ), the World Health Organization Health and Work Performance Questionnaire (WHO-HPQ) and the scales on demographic characteristics, were administered at baseline (August 2009). At one-year follow-up (August 2010), the OJQ and WHO-HPQ were used again to assess organizational justice and job performance. The change in organizational justice was measured by dichotomizing each OJQ subscale score by median at baseline and follow-up, and the participants were classified into four groups (i.e., stable low, adverse change, favorable change and stable high). Analysis of covariance (ANCOVA) was employed. After adjusting for demographic and occupational characteristics and job performance at baseline, the groups classified based on the change in procedural justice differed significantly in job performance at follow-up (ANCOVA: F [3, 1097]=4.35, p<0.01). Multiple comparisons revealed that the stable high procedural justice group had significantly higher job performance at follow-up compared with the stable low procedural justice group. The groups classified based on change in interactional justice did not differ significantly in job performance at follow-up (p>0.05). The present findings suggest that keeping the level of procedural justice high predicts higher levels of job performance, whereas the psychosocial factor of interactional justice is not so important for predicting job performance.
Mitigating Stress Waves Using Nanofoams and Nanohoneycombs
2014-04-16
In the following sections, we present our work in chronological order. 3 1. TWO-PARAMETER STUDY ON SILICA NANOFOAMS 1.1 Preparation...and Characterization of Silica Nanofoams Following the work in the last period of performance, we performed a systematic study on silica nanofoam...12.98MPa Peak value of transmission pulse: 5.32MPa Normalized peak value: 0.410 Pressure reduction: 0.02 MPa 19 2. SINGLE-PARAMETER STUDY ON
ERIC Educational Resources Information Center
Omwirhiren, Efe M.
2015-01-01
The present study was initiated to determine how academic achievement and retention in chemistry is enhanced using the two instructional methods among SSII students and ascertained the differential performance of male and female students in chemistry with a view of improving student performance in chemistry. The study adopted a non-equivalent…
Prospective memory across adolescence: the effects of age and cue focality.
Wang, Lijuan; Altgassen, Mareike; Liu, Wei; Xiong, Weirui; Akgün, Canan; Kliegel, Matthias
2011-01-01
The present study examined the role of controlled attention in age differences in event-based prospective memory performance across adolescence. The researchers tested whether presenting the prospective memory cue in or out of focal awareness of the ongoing task (resulting in low versus high demands for controlled attention, respectively) might affect age-related prospective memory performance. In total, 119 Chinese participants ages 13 to 20 took part in this study (60 adolescents: age M = 13.26 years, SD = 0.50; 23 boys; 59 young adults: age M = 19.70 years, SD = 0.87; 19 men). Findings demonstrated a significant interaction, F(1, 114) = 6.41, p < .05. No effect of age on prospective memory performance was revealed when a focal cue was used (F < 1), whereas there was a reliable age effect between adolescents and young adults when nonfocal prospective memory cues were presented, F(1, 59) = 16.13, p < .01. This pattern of results suggests that the interplay of both available resources of controlled attention and working memory, along with specific task demands, may contribute to possible age differences in prospective memory performance across adolescence. Results are discussed in the context of the multiprocess theory of prospective memory.
Structural properties of lead-lithium alloys
NASA Astrophysics Data System (ADS)
Khambholja, S. G.; Satikunvar, D. D.; Abhishek, Agraj; Thakore, B. Y.
2018-05-01
Lead-Lihtium alloys have found large number of applications as liquid metal coolants in nuclear reactors. Large number of experimental work is reported for this system. However, complete theoretical description is still rare. In this scenario, we in the present work report the study of ground state properties of Lead-Lithium system. The present study is performed using plane wave pseudopotential density functional theory as implemented in Quantum ESPRESSO package. The theoretical findings are in agreement with previously reported experimental data. Some conclusions are drawn based on present study, which will be helpful for a comprehensive study.
Jiménez-Arredondo, Ramón Ernesto; Brambila-Tapia, Aniel Jessica Leticia; Mercado-Silva, Francisco Miguel; Ortiz-Aranda, Martha; Benites-Godinez, Verónica; Olmos-García-de-Alba, Graciela; Figuera, Luis Eduardo
2017-03-01
Mucopolysaccharidosis type II or Hunter syndrome (MPS II) is a genetic disease that can course with intellectual impairment and central nervous system (CNS) alterations. To date, no report has documented electroencephalogram (EEG) measures associated with CNS alterations, detected by imaging studies, and the history of seizures in patients with MPS II. Therefore, we decided to search this association. We included 9 patients with MPS II and performed imaging studies of the brain to detect the presence of cortico-subcortical atrophy, enlarged subarachnoid space and supratentorial ventricular size. Additionally, we performed EEG studies in sleep and awake conditions and a complete clinical description. Five out of the nine patients presented history of seizures and all except one patient (88.9%) presented some CNS structural alteration in the imaging studies, being the most frequent the cortico-subcortical atrophy (77.8%). The EEG results showed low amplitude in all patients and low voltage in sleep condition in eight patients with interhemispheric asymmetry in six patients during awake and sleep conditions. Although the five patients with history of seizures did not present a distinctive EEG anomaly, four of them presented some structural alteration in the imaging studies. In conclusion, most patients presented structural alterations in the CNS; likewise, all of them presented EEG anomalies mainly during sleep conditions. However, a clear association between EEG, CNS and the history of seizures was not established.
NASA Technical Reports Server (NTRS)
Morris, S. J., Jr.
1979-01-01
Performance estimation, weights, and scaling laws for an eight-blade highly loaded propeller combined with an advanced turboshaft engine are presented. The data are useful for planned aircraft mission studies using the turboprop propulsion system. Comparisons are made between the performance of the 1990+ technology turboprop propulsion system and the performance of both a current technology turbofan and an 1990+ technology turbofan.
Employee performance in the knowledge economy: Capturing the keys to success
Fauth, Rebecca; Bevan, Stephen; Mills, Peter
2009-01-01
The present study examines the key determinants of employee performance in a knowledge-intensive service firm located in the UK. Using data from a pilot study, we mapped eight performance-related behaviors to two measures of global performance to isolate the strongest predictors of the latter. We also examined the degree to which these associations varied depending on whether employees or their managers reported on performance as well as according to the degree of complexity (eg, ongoing learning, multitasking, problem solving, etc.) present in workers’ jobs. Findings revealed that more traditional employee performance-related behaviors (eg, dependability) as well as behaviors that have likely increased in importance in the knowledge economy (eg, sharing ideas and information) accounted for the most variance in reported global performance. Sharing ideas and information was a particularly important predictor for workers in complex jobs. When the performance-related behaviors were regressed on the organization’s annual employee appraisal ratings, only dependability and time management behaviors were significantly associated with the outcome. As organizational success increasingly is dependent on intangible inputs stemming from the ideas, innovations and creativity of its workforce, organizations need to ensure that they are capturing the full range of behaviors that help to define their success. Further research with a diverse range of organizations will help define this further. PMID:22110316
Dietz, Christina; Dekker, Matthijs; Piqueras-Fiszman, Betina
2017-09-01
Matcha tea is gaining popularity throughout the world in recent years and is frequently referred to as a mood-and-brain food. Previous research has demonstrated that three constituents present in matcha tea, l-theanine, epigallocatechin gallate (EGCG), and caffeine, affect mood and cognitive performance. However, to date there are no studies assessing the effect of matcha tea itself. The present study investigates these effects by means of a human intervention study administering matcha tea and a matcha containing product. Using a randomized, placebo-controlled, single-blind study, 23 consumers participated in four test sessions. In each session, participants consumed one of the four test products: matcha tea, matcha tea bar (each containing 4g matcha tea powder), placebo tea, or placebo bar. The assessment was performed at baseline and 60min post-treatment. The participants performed a set of cognitive tests assessing attention, information processing, working memory, and episodic memory. The mood state was measured by means of a Profile of Mood States (POMS). After consuming the matcha products compared to placebo versions, there were mainly significant improvements in tasks measuring basic attention abilities and psychomotor speed in response to stimuli over a defined period of time. In contrast to expectations, the effect was barely present in the other cognitive tasks. The POMS results revealed no significant changes in mood. The influence of the food matrix was demonstrated by the fact that on most cognitive performance measures the drink format outperformed the bar format, particularly in tasks measuring speed of spatial working memory and delayed picture recognition. This study suggests that matcha tea consumed in a realistic dose can induce slight effects on speed of attention and episodic secondary memory to a low degree. Further studies are required to elucidate the influences of the food matrix. Copyright © 2017 Elsevier Ltd. All rights reserved.
Callosotomy affects performance IQ: A meta-analysis of individual participant data.
Westerhausen, René; Karud, Celine M R
2018-02-05
Morphometric neuroimaging studies on healthy adult individuals regularly report a positive association between intelligence test performance (IQ) and structural properties of the corpus callosum (CC). At the same time, studies examining the effect of callosotomy on epilepsy patients report only negligible changes in IQ as result of the surgery, partially contradicting the findings of the morphometry studies. Objective of the present meta-analysis of individual participant data (IPD) of 87 cases from 16 reports was to re-investigate the effect of callosotomy on full scale IQ as well as on the verbal and performance subscale under special consideration of two possible moderating factors: pre-surgical IQ levels and the extent of the surgery (complete vs. anterior transsection). The main finding was that callosotomy selectively affects performance IQ, whereby the effect is modulated by the pre-surgical level of performance. Patients with an above-median pre-surgery performance IQ level show a significant average decrease of -5.44 (CI 95% : - 8.33 to - 2.56) IQ points following the surgery, while the below-median group does not reveal a significant change in IQ (mean change: 1.01 IQ points; CI 95% : -1.83 to 3.86). Thus, the present analyses support the notion that callosotomy has a negative effect on the patients' performance IQ, but only in those patients, who at least have an average performance levels before the surgery. This observation also lends support to the findings of previous morphometry studies, indicating that the frequently observed CC-IQ correlation might indeed reflect a functional contribution of callosal interhemispheric connectivity to intelligence-test performance. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
Wan, S A; Teh, C L; Jobli, A T
2016-11-01
Objective The aim of this study was to examine the clinical features, treatment and outcome of systemic lupus erythematosus (SLE) patients in our centre who presented with lupus pneumonitis as the initial manifestation. Methods We performed a retrospective review of all patients who presented with lupus pneumonitis during the initial SLE manifestation from March 2006 to March 2015. Results There were a total of five patients in our study who presented with fever and cough as the main clinical features. All patients had pulmonary infiltrates on chest radiographs. High-resolution computed tomography, which was performed in two patients, showed ground glass opacities with patchy consolidations bilaterally. All patients received high-dose steroids, 80% received intravenous cyclophosphamide and 60% received intravenous immunoglobulin. Two patients died from severe lupus pneumonitis within 2 weeks of admission despite treatment with ventilation, steroids, cyclophosphamide and intravenous immunoglobulin. Conclusions Acute lupus pneumonitis is an uncommon presentation of SLE. Mortality in this case series is 40%.
Haji Ali Afzali, Hossein; Gray, Jodi; Karnon, Jonathan
2013-04-01
Decision analytic models play an increasingly important role in the economic evaluation of health technologies. Given uncertainties around the assumptions used to develop such models, several guidelines have been published to identify and assess 'best practice' in the model development process, including general modelling approach (e.g., time horizon), model structure, input data and model performance evaluation. This paper focuses on model performance evaluation. In the absence of a sufficient level of detail around model performance evaluation, concerns regarding the accuracy of model outputs, and hence the credibility of such models, are frequently raised. Following presentation of its components, a review of the application and reporting of model performance evaluation is presented. Taking cardiovascular disease as an illustrative example, the review investigates the use of face validity, internal validity, external validity, and cross model validity. As a part of the performance evaluation process, model calibration is also discussed and its use in applied studies investigated. The review found that the application and reporting of model performance evaluation across 81 studies of treatment for cardiovascular disease was variable. Cross-model validation was reported in 55 % of the reviewed studies, though the level of detail provided varied considerably. We found that very few studies documented other types of validity, and only 6 % of the reviewed articles reported a calibration process. Considering the above findings, we propose a comprehensive model performance evaluation framework (checklist), informed by a review of best-practice guidelines. This framework provides a basis for more accurate and consistent documentation of model performance evaluation. This will improve the peer review process and the comparability of modelling studies. Recognising the fundamental role of decision analytic models in informing public funding decisions, the proposed framework should usefully inform guidelines for preparing submissions to reimbursement bodies.
Gawęda, Ł; Li, E; Lavoie, S; Whitford, T J; Moritz, S; Nelson, B
2018-01-01
Self-monitoring biases and overconfidence in incorrect judgments have been suggested as playing a role in schizophrenia spectrum disorders. Little is known about whether self-monitoring biases may contribute to early risk factors for psychosis. In this study, action self-monitoring (i.e., discrimination between imagined and performed actions) was investigated, along with confidence in judgments among ultra-high risk (UHR) for psychosis individuals and first-episode psychosis (FEP) patients. Thirty-six UHR for psychosis individuals, 25 FEP patients and 33 healthy controls (CON) participated in the study. Participants were assessed with the Action memory task. Simple actions were presented to participants verbally or non-verbally. Some actions were required to be physically performed and others were imagined. Participants were asked whether the action was presented verbally or non-verbally (action presentation type discrimination), and whether the action was performed or imagined (self-monitoring). Confidence self-ratings related to self-monitoring responses were obtained. The analysis of self-monitoring revealed that both UHR and FEP groups misattributed imagined actions as being performed (i.e., self-monitoring errors) significantly more often than the CON group. There were no differences regarding performed actions as being imagined. UHR and FEP groups made their false responses with higher confidence in their judgments than the CON group. There were no group differences regarding discrimination between the types of actions presented (verbal vs non-verbal). A specific type of self-monitoring bias (i.e., misattributing imagined actions with performed actions), accompanied by high confidence in this judgment, may be a risk factor for the subsequent development of a psychotic disorder. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Influence of bromide on the performance of the amphipod Hyalella azteca in reconstituted waters
Ivey, Chris D.; Ingersoll, Christopher G.
2016-01-01
Poor performance of the amphipod Hyalella azteca has been observed in exposures using reconstituted waters. Previous studies have reported success in H. azteca water-only exposures with the addition of relatively high concentrations of bromide. The present study evaluated the influence of lower environmentally representative concentrations of bromide on the response ofH. azteca in 42-d water-only exposures. Improved performance of H. azteca was observed in reconstituted waters with >0.02 mg Br/L.
Position-specific behaviors and their impact on crew performance: Implications for training
NASA Technical Reports Server (NTRS)
Law, J. Randolph
1993-01-01
The present study was motivated by results from a preliminary report documenting the impact of specific crewmembers on overall crew performance (Wilhelm & Law, 1992), and a cross-airline cross-fleet project investigating human factors behaviors of commercial aviation flightcrews (Helmreich, Butler, Whilhelm, & Lofaro, 1992). The purpose of the current investigation is to study how position-specific behaviors impact flightcrew performance, and how these position-specific behaviors differ between two airlines and two flying environments. Implications for training will also be addressed.
FLAME: A platform for high performance computing of complex systems, applied for three case studies
Kiran, Mariam; Bicak, Mesude; Maleki-Dizaji, Saeedeh; ...
2011-01-01
FLAME allows complex models to be automatically parallelised on High Performance Computing (HPC) grids enabling large number of agents to be simulated over short periods of time. Modellers are hindered by complexities of porting models on parallel platforms and time taken to run large simulations on a single machine, which FLAME overcomes. Three case studies from different disciplines were modelled using FLAME, and are presented along with their performance results on a grid.
Enhanced Component Performance Study. Emergency Diesel Generators 1998–2013
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schroeder, John Alton
2014-11-01
This report presents an enhanced performance evaluation of emergency diesel generators (EDGs) at U.S. commercial nuclear power plants. This report evaluates component performance over time using Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES) data from 1998 through 2013 and maintenance unavailability (UA) performance data using Mitigating Systems Performance Index (MSPI) Basis Document data from 2002 through 2013. The objective is to present an analysis of factors that could influence the system and component trends in addition to annual performance trends of failure rates and probabilities. The factors analyzed for the EDG component are the differences in failuresmore » between all demands and actual unplanned engineered safety feature (ESF) demands, differences among manufacturers, and differences among EDG ratings. Statistical analyses of these differences are performed and results showing whether pooling is acceptable across these factors. In addition, engineering analyses were performed with respect to time period and failure mode. The factors analyzed are: sub-component, failure cause, detection method, recovery, manufacturer, and EDG rating.« less
Using coal inside California for electric power
NASA Technical Reports Server (NTRS)
Moore, J. B.
1978-01-01
In a detailed analysis performed at Southern California Edison on a wide variety of technologies, the direct combustion of coal and medium BTU gas from coal were ranked just below nuclear power for future nonpetroleum based electric power generation. As a result, engineering studies were performed for demonstration projects for the direct combustion of coal and medium BTU gas from coal. Graphs are presented for power demand, and power cost. Direct coal combustion and coal gasification processes are presented.
ERIC Educational Resources Information Center
Entwistle, Noel J.; And Others
1977-01-01
Volume 1 discusses a large-scale follow-up study of the correlates of academic success in 2,595 college students. Volume 2 presents a philosophical and historical approach to studying educational objectives. (Available in microfiche from: Carfax Publishing Company, Haddon House, Dorchester-on-Thames, Oxford 0X9 8JZ, England.) (CP)
ERIC Educational Resources Information Center
Brabeck, Kalina M.; Sibley, Erin; Taubin, Patricia; Murcia, Angela
2016-01-01
The present study investigated the relationship between immigrant parent legal status and academic performance among U.S.-born children, ages 7-10. Building on previous research and a social ecological framework, the study further explored how social service use moderates the relationship between parent legal status and academic performance.…
ERIC Educational Resources Information Center
Lai, Mun Yee; Murray, Sara
2015-01-01
Most studies of students' understanding of decimals have been conducted within Western cultural settings. The broad aim of the present research was to gain insight into Chinese Hong Kong grade 6 students' general performance on a variety of decimals tasks. More specifically, the study aimed to explore students' mathematical reasoning for their use…
ERIC Educational Resources Information Center
Bhat, Anjana N.; Srinivasan, Sudha M.; Woxholdt, Colleen; Shield, Aaron
2018-01-01
Children with autism spectrum disorder present with a variety of social communication deficits such as atypicalities in social gaze and verbal and non-verbal communication delays as well as perceptuo-motor deficits like motor incoordination and dyspraxia. In this study, we had the unique opportunity to study praxis performance in deaf children…
LONG TERM STABILITY STUDY AT FNAL AND SLAC USING BINP DEVELOPED HYDROSTATIC LEVEL SYSTEM
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seryi, Andrei
2003-05-28
Long term ground stability is essential for achieving the performance goals of the Next Linear Collider. To characterize ground motion on relevant time scales, measurements have been performed at three geologically different locations using a hydrostatic level system developed specifically for these studies. Comparative results from the different sites are presented in this paper.
Assessing Number Sense Performance of Indonesian Elementary School Students
ERIC Educational Resources Information Center
Purnomo, Yoppy Wahyu; Kowiyah; Alyani, Fitri; Assiti, Saliza S.
2014-01-01
The intention of the present study is to know how students' performance on number sense based on the components of number sense and also the sub-components in it. The participants of the study are 80 six graders (12-13 year-old) from three different schools that represent the city, rural, and small town areas. The data were collected using the…
ERIC Educational Resources Information Center
DeFulio, Anthony; Crone-Todd, Darlene E.; Long, Lauren V.; Nuzzo, Paul A.; Silverman, Kenneth
2011-01-01
Keyboarding skill is an important target for adult education programs due to the ubiquity of computers in modern work environments. A previous study showed that novice typists learned key locations quickly but that fluency took a relatively long time to develop. In the present study, novice typists achieved fluent performance in nearly half the…
ERIC Educational Resources Information Center
Zarei, Gholam Reza; Pourghasemian, Hossein; Jalali, Hassan
2017-01-01
The present study attempts to give an account of how students represent writing task in an EAP course. Further, the study is intended to discover if learners' mental representation of writing would contribute to their written performance. During a 16-week term, students were instructed to practice writing as a problem solving activity. At almost…
ERIC Educational Resources Information Center
Thissen, David; Wainer, Howard
Simulation studies of the performance of (potentially) robust statistical estimation produce large quantities of numbers in the form of performance indices of the various estimators under various conditions. This report presents a multivariate graphical display used to aid in the digestion of the plentiful results in a current study of Item…
ERIC Educational Resources Information Center
Mackey, Allyson P.; Park, Anne T.; Robinson, Sydney T.; Gabrieli, John D. E.
2017-01-01
Cognitive skills are associated with academic performance, but little is known about how to improve these skills in the classroom. Here, we present the results of a pilot study in which teachers were trained to engage students in cognitive skill practice through playing games. Fifth-grade students at an experimental charter school were randomly…
Phonological and Executive Working Memory in L2 Task-Based Speech Planning and Performance
ERIC Educational Resources Information Center
Wen, Zhisheng
2016-01-01
The present study sets out to explore the distinctive roles played by two working memory (WM) components in various aspects of L2 task-based speech planning and performance. A group of 40 post-intermediate proficiency level Chinese EFL learners took part in the empirical study. Following the tenets and basic principles of the…
The Effects of Student Employment on Academic Performance in Tatarstan Higher Education Institutions
ERIC Educational Resources Information Center
Yanbarisova, D. M.
2015-01-01
Today, combining academic study with employment is typical for a wide range of students. There are many reasons why students choose to work, from the need to integrate into the job market to the desire to fill spare time. The present article investigates how various study and work combinations affect the academic performance of students in their…
ERIC Educational Resources Information Center
Filippatou, Diamanto; Kaldi, Stavroula
2010-01-01
This study focuses upon the effectiveness of project-based learning on primary school pupils with learning difficulties regarding their academic performance and attitudes towards self efficacy, task value, group work and teaching methods applied. The present study is a part of a larger one that included six Greek fourth-grade primary school…
Constantinidou, Fofi; Evripidou, Christiana
2012-01-01
This study investigated the effects of stimulus presentation modality on working memory performance in children with reading disabilities (RD) and in typically developing children (TDC), all native speakers of Greek. It was hypothesized that the visual presentation of common objects would result in improved learning and recall performance as compared to the auditory presentation of stimuli. Twenty children, ages 10-12, diagnosed with RD were matched to 20 TDC age peers. The experimental tasks implemented a multitrial verbal learning paradigm incorporating three modalities: auditory, visual, and auditory plus visual. Significant group differences were noted on language, verbal and nonverbal memory, and measures of executive abilities. A mixed-model MANOVA indicated that children with RD had a slower learning curve and recalled fewer words than TDC across experimental modalities. Both groups of participants benefited from the visual presentation of objects; however, children with RD showed the greatest gains during this condition. In conclusion, working memory for common verbal items is impaired in children with RD; however, performance can be facilitated, and learning efficiency maximized, when information is presented visually. The results provide further evidence for the pictorial superiority hypothesis and the theory that pictorial presentation of verbal stimuli is adequate for dual coding.
Duvekot, Jorieke; Schalk, Rozemarijn D. F.; Tuinenburg, Eveline M.; Westenberg, P. Michiel
2009-01-01
Social anxiety in adolescents has frequently been linked to negative outcomes from social interactions. The present study investigated whether socially anxious adolescents are treated negatively by their classmates and which characteristics of socially anxious adolescents could explain negative social responses. Classroom observations of class behavior were made during oral presentations of 94 students (60% females) in the ages of 13–18 years. Speakers’ social performance, speech quality, and nervousness during the presentation were also rated. Findings showed that the social performance of socially anxious students was a predictor of class behavior, whereas their overt nervousness was not. Surprisingly, the quality of their speech was negatively related to class behavior. Implications of these findings for the treatment of socially anxious adolescents are discussed. PMID:19842023
ERIC Educational Resources Information Center
Sungur, Semra; Senler, Burcu
2010-01-01
The present study aimed at investigating elementary students' academic motivation (intrinsic motivation, external regulation, introjected regulation, identified regulation, and amotivation), achievement goals (mastery approach goals, mastery avoidance goals, performance approach goals, performance avoidance goals), competence expectancies, and…
Polymer-impregnated bridge slabs : performance over 10 years.
DOT National Transportation Integrated Search
1990-01-01
This report presents the results of a study to evaluate the performance over a 10-year period of slabs that were impregnated to a depth of about 1 in with a monomer that was subsequently polymerized (shallow polymer impregnation). The slabs were used...
Performance evaluation of Louisiana's AASHO satellite test sections : final report.
DOT National Transportation Integrated Search
1979-07-01
It is beyond the scope of this study to attempt to isolate the effect of individual design assumptions on pavement life. : A performance evaluation (to determine present serviceability, end of life, etc.) of selected Portland Cement Concrete (P.C.C.)...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pern, F. J.; Watson, G. L.; Glick, S. H.
2001-10-01
Presented at the 2001 NCPV Program Review Meeting: Study of photothermal stability of special EVA encapsulant by accelerated exposure testing and analysis of causes of performance degradation on a-Si modules.
Neuromorphic Learning From Noisy Data
NASA Technical Reports Server (NTRS)
Merrill, Walter C.; Troudet, Terry
1993-01-01
Two reports present numerical study of performance of feedforward neural network trained by back-propagation algorithm in learning continuous-valued mappings from data corrupted by noise. Two types of noise considered: plant noise which affects dynamics of controlled process and data-processing noise, which occurs during analog processing and digital sampling of signals. Study performed with view toward use of neural networks as neurocontrollers to substitute for, or enhance, performances of human experts in controlling mechanical devices in presence of sensor and actuator noise and to enhance performances of more-conventional digital feedback electronic process controllers in noisy environments.
Sensitivity study of the monogroove with screen heat pipe design
NASA Technical Reports Server (NTRS)
Evans, Austin L.; Joyce, Martin
1988-01-01
The present sensitivity study of design variable effects on the performance of a monogroove-with-screen heat pipe obtains performance curves for maximum heat-transfer rates vs. operating temperatures by means of a computer code; performance projections for both 1-g and zero-g conditions are obtainable. The variables in question were liquid and vapor channel design, wall groove design, and the number of feed lines in the evaporator and condenser. The effect on performance of three different working fluids, namely ammonia, methanol, and water, were also determined. Greatest sensitivity was to changes in liquid and vapor channel diameters.
Experimental performance of three design factors for ventral nozzles for SSTOVL aircraft
NASA Technical Reports Server (NTRS)
Esker, Barbara S.; Perusek, Gail P.
1992-01-01
An experimental study of three variations of a ventral nozzle system for supersonic short-takeoff and vertical-landing (SSTOVL) aircraft was performed at the NASA LeRC Powered Lift Facility. These test results include the effects of an annular duct flow into the ventral duct, a blocked tailpipe, and a short ventral duct length. An analytical study was also performed on the short ventral duct configuration using the PARC3D computational dynamics code. Data presented include pressure losses, thrust and flow performance, internal flow visualization, and pressure distributions at the exit plane of the ventral nozzle.
Energy Efficient Engine: Combustor component performance program
NASA Technical Reports Server (NTRS)
Dubiel, D. J.
1986-01-01
The results of the Combustor Component Performance analysis as developed under the Energy Efficient Engine (EEE) program are presented. This study was conducted to demonstrate the aerothermal and environmental goals established for the EEE program and to identify areas where refinements might be made to meet future combustor requirements. In this study, a full annular combustor test rig was used to establish emission levels and combustor performance for comparison with those indicated by the supporting technology program. In addition, a combustor sector test rig was employed to examine differences in emissions and liner temperatures obtained during the full annular performance and supporting technology tests.
Mohamed, Saleh M H; Börger, Norbert A; Geuze, Reint H; van der Meere, Jaap J
2016-10-01
Many clinical studies have shown that performance of subjects with attention-deficit/hyperactivity disorder (ADHD) is impaired when stimuli are presented at a slow rate compared to a medium or fast rate. According to the cognitive-energetic model, this finding may reflect difficulty in allocating sufficient effort to regulate the motor activation state. Other studies have shown that the left hemisphere is relatively responsible for keeping humans motivated, allocating sufficient effort to complete their tasks. This leads to a prediction that poor effort allocation might be associated with an affected left-hemisphere functioning in ADHD. So far, this prediction has not been directly tested, which is the aim of the present study. Seventy-seven adults with various scores on the Conners' Adult ADHD Rating Scale performed a lateralized lexical decision task in three conditions with stimuli presented in a fast, a medium, and a slow rate. The left-hemisphere functioning was measured in terms of visual field advantage (better performance for the right than for the left visual field). All subjects showed an increased right visual field advantage for word processing in the slow presentation rate of stimuli compared to the fast and the medium rate. Higher ADHD scores were related to a reduced right visual field advantage in the slow rate only. The present findings suggest that ADHD symptomatology is associated with less involvement of the left hemisphere when extra effort allocation is needed to optimize the low motor activation state.
Holcomb, H H; Ritzl, E K; Medoff, D R; Nevitt, J; Gordon, B; Tamminga, C A
1995-06-29
Psychophysical and cognitive studies carried out in schizophrenic patients show high within-group performance variance and sizable differences between patients and normal volunteers. Experimental manipulation of a target's signal-to-noise characteristics can, however, make a given task more or less difficult for a given subject. Such signal-to-noise manipulations can substantially reduce performance differences between individuals. Frequency and presentation level (volume) changes of an auditory tone can make a sound more or less difficult to recognize. This study determined how the discrimination accuracy of medicated schizophrenic patients and normal volunteers changed when the frequency difference between two tones (high frequency vs. low frequency) and the presentation levels of tones were systematically degraded. The investigators hypothesized that each group would become impaired in its discrimination accuracy when tone signals were degraded by making the frequencies more similar and the presentation levels lower. Schizophrenic patients were slower and less accurate than normal volunteers on tests using four tone levels and two frequency differences; the schizophrenic patient group showed a significant decrement in accuracy when the signal-to-noise characteristics of the target tones were degraded. The benefits of controlling stimulus discrimination difficulty in functional imaging paradigms are discussed.
Visual information can hinder working memory processing of speech.
Mishra, Sushmit; Lunner, Thomas; Stenfelt, Stefan; Rönnberg, Jerker; Rudner, Mary
2013-08-01
The purpose of the present study was to evaluate the new Cognitive Spare Capacity Test (CSCT), which measures aspects of working memory capacity for heard speech in the audiovisual and auditory-only modalities of presentation. In Experiment 1, 20 young adults with normal hearing performed the CSCT and an independent battery of cognitive tests. In the CSCT, they listened to and recalled 2-digit numbers according to instructions inducing executive processing at 2 different memory loads. In Experiment 2, 10 participants performed a less executively demanding free recall task using the same stimuli. CSCT performance demonstrated an effect of memory load and was associated with independent measures of executive function and inference making but not with general working memory capacity. Audiovisual presentation was associated with lower CSCT scores but higher free recall performance scores. CSCT is an executively challenging test of the ability to process heard speech. It captures cognitive aspects of listening related to sentence comprehension that are quantitatively and qualitatively different from working memory capacity. Visual information provided in the audiovisual modality of presentation can hinder executive processing in working memory of nondegraded speech material.
Performance and operational improvements made to the Waukesha AT27-GL engine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reinbold, E.O.
1996-12-31
This paper presents the results of combustion and engine performance studies performed on the AT27GL lean burn engine. One study was to evaluate the effect of the pre-combustion chamber cup geometry on engine performance under several operating conditions including: Air-Fuel Ratio (AFR), ignition timing, and engine load. The study examined several combustion parameters; including IMEP, coefficient of variation of IMEP, heat release rates, and maximum combustion pressures. The study also examined engine thermal efficiency, and brake specific emissions of Oxides of Nitrogen, Carbon Monoxide, and Total Hydrocarbons (gaseous). Studies were also performed on different spark plug designs, comparing firing voltages,more » and electrode temperatures while operating under conditions of varying AFR, and ignition timing. In addition an Air-Fuel-Ratio controller was recently tested and released on the engine. The controller was tested under conditions of varying fuel quality, along with a detonation control system.« less
Surface-based haemangioma of the tibia: a case report.
Di Giorgio, Luigi; Valentini, Matteo Benedetti; Mastantuono, Marco; Touloupakis, Georgios
2008-12-01
We present in this paper a case of surface-based haemangioma of the tibia in a 34-year-old patient which had been misdiagnosed as periostitis. X-ray examination demonstrated a periosteal reaction, confirmed by a MRI showing a soft tissue mass adjacent to bone. We performed an incisional biopsy and made a diagnosis of haemangioma only after examining the histological results. An angiographic study was performed in order to have embolisation of the vessels, but this was not possible because of the excessive number and calibre of afferent arteries. No further symptoms arose after biopsy and therefore an en bloc or radical excision was not performed. Indications for making a correct diagnosis and performing a suitable treatment are presented below.
Understanding adolescents' sleep patterns and school performance: a critical appraisal.
Wolfson, Amy R; Carskadon, Mary A
2003-12-01
The present paper reviews and critiques studies assessing the relation between sleep patterns, sleep quality, and school performance of adolescents attending middle school, high school, and/or college. The majority of studies relied on self-report, yet the researchers approached the question with different designs and measures. Specifically, studies looked at (1) sleep/wake patterns and usual grades, (2) school start time and phase preference in relation to sleep habits and quality and academic performance, and (3) sleep patterns and classroom performance (e.g., examination grades). The findings strongly indicate that self-reported shortened total sleep time, erratic sleep/wake schedules, late bed and rise times, and poor sleep quality are negatively associated with academic performance for adolescents from middle school through the college years. Limitations of the current published studies are also discussed in detail in this review.
Palazzo, M Carlotta; Arici, Chiara; Cremaschi, Laura; Cristoffanini, Marta; Dobrea, Cristina; Dell'Osso, Bernardo; Altamura, A Carlo
2017-01-01
Cognitive impairment may affect patients with Bipolar Disorder (BD) beyond the acute episodes, qualifying as a potential endophenotype. However, which cognitive domains are specifically affected in euthymic patients with BD and the potential influence of confounding factors ( e.g. , age and concomitant pharmacological treatment) are still a matter of debate. The present study was, therefore, conducted to assess cognitive performance across specific domains in euthymic bipolar patients, not older than 50 years (to avoid potential age-related bias) versus healthy controls (HCs). A cognitive task battery, including the Wisconsin Card Test, Span Attention Test, Tower of London, Trail Making Test, Verbal Fluency Test, Matrices Scores and N-Back, was administered to 62 subjects (30 bipolar patients and 32 matched HCs) and differences between the groups analyzed. Bipolar patients performed significantly worse than HCs in the Span Forward task, in the expression of Verbal Fluency Test (Category) and in the N-Back task (all p<.05), with marginal differences between BD I and BD II patients. The present study pointed out significant differences in terms of cognitive performance between euthymic bipolar patients and HCs, supporting the notion that specific cognitive functions may remain impaired even after the resolution of the acute episodes in subjects suffering from BD. Future studies on larger samples are warranted to confirm the present results and further explore potential differences in cognitive impairment across specific bipolar subtypes.
The Influence of Social Style in Evaluating Academic Presentations of Engineering Projects
ERIC Educational Resources Information Center
Ortiz València, Héctor; García Carrillo, Águeda; González Benítez, Margarita
2012-01-01
An individual's social style is determined by behavioral patterns in the interactions with their peers. Some studies suggest that social style may influence the way in which an individual's performance is evaluated. We studied the effects that speakers' and evaluators' social styles have on the marks given for end-of-term presentations in a…
Test Item Linguistic Complexity and Assessments for Deaf Students
ERIC Educational Resources Information Center
Cawthon, Stephanie
2011-01-01
Linguistic complexity of test items is one test format element that has been studied in the context of struggling readers and their participation in paper-and-pencil tests. The present article presents findings from an exploratory study on the potential relationship between linguistic complexity and test performance for deaf readers. A total of 64…
ERIC Educational Resources Information Center
Vila, Francisca; Sanz, Amparo
2013-01-01
The importance of mathematical literacy in any scientific career is widely recognized. However, various studies report lack of numeracy and mathematical literacy in students from various countries. In the present work, we present a detailed study of the mathematical literacy of Spanish undergraduate students of Biology enrolled in a Plant…
Animals from the Outside In, Science (Experimental): 5314.01.
ERIC Educational Resources Information Center
Kleinman, David Z.
Presented is an outline of a basic course (low level) in biology for students whose interest and background are very limited. The study and dissection of earthworm, crayfish, perch, and bird are included. A detailed study of the frog is undertaken as a representative of the animal kingdom. Performance objectives are presented, as well as a course…
Faces and fitness: attractive evolutionary relationship or ugly hypothesis?
Smoliga, James M; Zavorsky, Gerald S
2015-11-01
In recent years, various studies have attempted to understand human evolution by examining relationships between athletic performance or physical fitness and facial attractiveness. Over a wide range of five homogeneous groups (n = 327), there is an approximate 3% shared variance between facial attractiveness and athletic performance or physical fitness (95% CI = 0.5-8%, p = 0.002). Further, studies relating human performance and attractiveness often have major methodological limitations that limit their generalizability. Thus, despite statistical significance, the association between facial attractiveness and human performance has questionable biological importance. Here, we present a critique of these studies and provide recommendations to improve the quality of future research in this realm. © 2015 The Author(s).
NASA Technical Reports Server (NTRS)
Nguyen, H. L.; Addy, H. E.; Bond, T. H.; Lee, C. M.; Chun, K. S.
1987-01-01
A computer simulation which models engine performance of the Direct Injection Stratified Charge (DISC) rotary engines was used to study the effect of variations in engine design and operating parameters on engine performance and efficiency of an Outboard Marine Corporation (OMC) experimental rotary combustion engine. Engine pressure data were used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine data were compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the rotary engine using advanced heat engine concepts such as faster combustion, reduced leakage, and turbocharging is also presented.
Gastroprotective effect of Senecio candicans DC on experimental ulcer models.
Hariprasath, Lakshmanan; Raman, Jegadeesh; Nanjian, Raaman
2012-03-06
Senecio candicans DC (Asteraceae) is used as a remedy for gastric ulcer and stomach pain in the Nilgiris district, Tamil Nadu for which no scientific evidence exists. The present study was performed to evaluate the gastroprotective effects and acute oral toxicity of aqueous leaf extract of Senecio candicans (AESC) in experimental models. The antiulcerogenic activity of AESC was performed in two different ulcer models viz., pylorus-ligated model and ethanol-induced model using Wistar albino rats. Acute toxicity study was also performed to get information on the admissible dose for treatment of ulcer. Preliminary phytochemical screening of AESC was performed to find the active principles present, which are thus responsible for the antiulcerogenic activity. DPPH assay was performed to confirm the antioxidant activity of AESC. The acute toxicity study did not show any mortality up to 2500mg/kg b.w. of AESC. Both the ulcer models showed gastroprotective effect comparable to that of the standard Omeprazole. The results of antioxidant enzymes, histopathology sections, ATPase and mucus content of gastric secretion showed that several mechanisms are involved in the gastroprotective effect. The preliminary phytochemical screening revealed the presence of alkaloids, flavonoids and steroids in AESC. The DPPH assay confirmed the antioxidant activity of AESC. The traditional consumption of AESC for the treatment of gastric ulcer is thus true, the antioxidant constituents present in the extract plays a major role in the gastroprotective activity, but since Senecio species are known for the presence of pyrrolizidine alkaloids, a detailed study in future is required to describe the safe dose for a prolonged period. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Yiadom, Maame Yaa A B; Mumma, Bryn E; Baugh, Christopher W; Patterson, Brian W; Mills, Angela M; Salazar, Gilberto; Tanski, Mary; Jenkins, Cathy A; Vogus, Timothy J; Miller, Karen F; Jackson, Brittney E; Lehmann, Christoph U; Dorner, Stephen C; West, Jennifer L; Wang, Thomas J; Collins, Sean P; Dittus, Robert S; Bernard, Gordon R; Storrow, Alan B; Liu, Dandan
2018-05-03
Advances in ST-segment elevation myocardial infarction (STEMI) management have involved improving the clinical processes connecting patients with timely emergency cardiovascular care. Screening upon emergency department (ED) arrival for an early ECG to diagnose STEMI, however, is not optimal for all patients. In addition, the degree to which timely screening and diagnosis are associated with improved time to intervention and postpercutaneous coronary intervention outcomes, under more contemporary practice conditions, is not known. We present the methods for a retrospective multicentre cohort study anticipated to include 1220 patients across seven EDs to (1) evaluate the relationship between timely screening and diagnosis with treatment and postintervention clinical outcomes; (2) introduce novel measures for cross-facility performance comparisons of screening and diagnostic care team performance including: door-to-screening, door-to-diagnosis and door-to-catheterisation laboratory arrival times and (3) describe the use of electronic health record data in tandem with an existing disease registry. The completion of this study will provide critical feedback on the quality of screening and diagnostic performance within the contemporary STEMI care pathway that can be used to (1) improve emergency care delivery for patients with STEMI presenting to the ED, (2) present novel metrics for the comparison of screening and diagnostic care and (3) inform the development of screening and diagnostic support tools that could be translated to other care environments. We will disseminate our results via publication and quality performance data sharing with each site. Institutional ethics review approval was received prior to study initiation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Huffmeijer, Renske; Bakermans-Kranenburg, Marian J; Alink, Lenneke R A; van IJzendoorn, Marinus H
2014-06-02
Parental use of love withdrawal is thought to affect children's later psychological functioning because it creates a link between children's performance and relational consequences. In addition, recent studies have begun to show that experiences of love withdrawal also relate to the neural processing of socio-emotional information relevant to a performance-relational consequence link, and can moderate effects of oxytocin on social information processing and behavior. The current study follows-up on our previous results by attempting to confirm and extend previous findings indicating that experiences of maternal love withdrawal are related to electrocortical responses to emotional faces presented with performance feedback. More maternal love withdrawal was related to enhanced early processing of facial feedback stimuli (reflected in more positive VPP amplitudes, and confirming previous findings). However, attentional engagement with and processing of the stimuli at a later stage were diminished in those reporting higher maternal love withdrawal (reflected in less positive LPP amplitudes, and diverging from previous findings). Maternal love withdrawal affects the processing of emotional faces presented with performance feedback differently in different stages of neural processing.
Pristine and γ-irradiated halloysite reinforced epoxy nanocomposites - Insight study
NASA Astrophysics Data System (ADS)
Saif, Muhammad Jawwad; Naveed, Muhammad; Zia, Khalid Mahmood; Asif, Muhammad
2016-10-01
The present study focuses on development of epoxy system reinforced with naturally occurring halloysite nanotubes (HNTs). A comparative study is presented describing the performance of pristine and γ-irradiated HNTs in an epoxy matrix. The γ-irradiation treatment was used for structural modification of natural pristine HNTs under air sealed environment at different absorbed doses and subsequently these irradiated HNTs were incorporated in epoxy resin with various wt% loadings. The consequences of γ-irradiation on HNTs were studied by FTIR and X-ray diffraction analysis (XRD) in terms of changes in functional groups and crystalline characteristics. An improvement is observed in mechanical properties and crack resistance of composites reinforced with γ-irradiated HNTs. The irradiated HNTs imparted an improved flexural and tensile strength/modulus along with better thermal performance.
Yousefnia, Nasim; Nekuei, Nafisehsadat; Farajzadegan, Ziba; Yadegarfar, Ghasem
2018-01-01
Domestic violence (DV) can threaten women's health. Healthcare providers (HCPs) may be the first to come into contact with a victim of DV. Their appropriate performance regarding a DV victim can decrease its complications. The aim of the present study was to investigate HCPs' performance regarding women experiencing DV in emergency and maternity wards of hospitals in Isfahan, Iran. The present descriptive, cross-sectional study was conducted among 300 HCPs working in emergency and maternity wards in hospitals in Isfahan. The participants were selected using quota random sampling from February to May 2016. A researcher-made questionnaire containing the five items of HCPs performance regarding DV (assessment, intervention, documentation, reference, and follow-up) was used to collect data. The reliability and validity of the questionnaire were confirmed, and the collected data were analyzed using SPSS software. Cronbach's alpha was used to assess the reliability of the questionnaires. To present a general description of the data (variables, mean, and standard deviation), the table of frequencies was designed. The performance of the participants regarding DV in the assessment (mean = 64.22), intervention (mean = 68.55), and reference stages (mean = 68.32) were average. However, in the documentation (mean = 72.55) and follow-up stages (mean = 23.10), their performance was good and weak respectively (criterion from 100). Based on the results, because of defects in providing services for women experiencing DV, a practical indigenous guideline should be provided to treat and support these women.
A Preliminary Study on the Possibility of Using Ultrasound in Driver Assistance Systems
NASA Astrophysics Data System (ADS)
Takahashi, Hiroshi; Honda, Hirohiko
This paper presents a preliminary study on the possibility of using ultrasound in driver assistance systems. Subjects' lap time in a driving video game was measured as an index of their performance of driving operations under acoustic conditions with and without an ultrasound signal at 23kHz, 70dB. The results show that the performance characteristics of the subjects changed when the ultrasound signal was presented. Ultrasound signal tends to concentrate on handling the vehicle and decreasing an attention to check the over speed driving, as a second task. We prove the possibility to apply ultrasound signal to control operator's attention and behavior.
TROPIX Power System Architecture
NASA Technical Reports Server (NTRS)
Manner, David B.; Hickman, J. Mark
1995-01-01
This document contains results obtained in the process of performing a power system definition study of the TROPIX power management and distribution system (PMAD). Requirements derived from the PMADs interaction with other spacecraft systems are discussed first. Since the design is dependent on the performance of the photovoltaics, there is a comprehensive discussion of the appropriate models for cells and arrays. A trade study of the array operating voltage and its effect on array bus mass is also presented. A system architecture is developed which makes use of a combination of high efficiency switching power convertors and analog regulators. Mass and volume estimates are presented for all subsystems.
NASA Technical Reports Server (NTRS)
1972-01-01
The results are reported of additional studies which were conducted to supplement conclusions drawn in the MSC Mission Report and analyses which were not completed in time to meet the Mission Report dealine. A detailed evaluation of the Abort Guidance System sensor assembly and results from the investigation of the X gyro loop anomaly are included. Further evidence is presented substantiating the excellent LM IMU performance obtained from preliminary indications. A detailed study is presented of the procedural changes implemented on Apollo 16 to diminish the number and duration of interruptions to the CSM DAP attitude maneuver during P20 Option 5 operations.
[Burnout-engagement and personality factors in medical students at a public university].
Hansen, Gladys V; D'Urso Villar, Marcela; Fracchia, Liliana N
2016-09-01
Medical students can develop burnout syndrome, characterized by exhaustion, cynical attitude towards study and negative consequences on wellbeing and academic performance. Engagement, theoretically syndrome "opposite" to burnout, shows a positive influence on personal and academic performance. To study the association of syndromes burnout and engagement with personality factors in medical students, a longitudinal observational, descriptive study of a cohort follow-up was performed. Three questionnaires were used: reduced inventory NEO Five-Factor (NEO FFI) administered at the beginning of the sixth year; the Maslach Burnout Inventory-Student Survey and Utrecht Work Engagement Scale, applied at the end of the seventh year. 120 students participated. The chance of presenting burnout was 3 times higher when the student had 0.26 times higher neuroticism and high extraversion lower when presented. The chance to present engagement was 10 times higher in students who had high extraversion (Multilevel logistic regression model, p<0.05). It would be important to further research into the mechanisms underlying personality factors could favor the onset of burnout and engagement syndromes, and carry out strategies to prevent the consequences of academic stress on the most vulnerable students.
Mooneyham, Benjamin W; Schooler, Jonathan W
2016-08-01
Mind wandering is associated with perceptual decoupling: the disengagement of attention from perception. This decoupling is deleterious to performance in many situations; however, we sought to determine whether it might occur in the service of performance in certain circumstances. In two studies, we examined the role of mind wandering in a test of "semantic satiation," a phenomenon in which the repeated presentation of a word reduces semantic priming for a subsequently presented semantic associate. We posited that the attentional and perceptual decoupling associated with mind wandering would reduce the amount of satiation in the semantic representations of repeatedly presented words, thus leading to a reduced semantic-satiation effect. Our results supported this hypothesis: Self-reported mind-wandering episodes (Study 1) and behavioral indices of decoupled attention (Study 2) were both predictive of maintained semantic priming in situations predicted to induce semantic satiation. Additionally, our results suggest that moderate inattention to repetitive stimuli is not sufficient to enable "dishabituation": the refreshment of cognitive performance that results from diverting attention away from the task at hand. Rather, full decoupling is necessary to reap the benefits of mind wandering and to minimize mind numbing.
Auditory-Visual Intermodal Matching of Small Numerosities in 6-Month-Old Infants
ERIC Educational Resources Information Center
Kobayashi, Tessei; Hiraki, Kazuo; Hasegawa, Toshikazu
2005-01-01
Recent studies have reported that preverbal infants are able to discriminate between numerosities of sets presented within a particular modality. There is still debate, however, over whether they are able to perform intermodal numerosity matching, i.e. to relate numerosities of sets presented with different sensory modalities. The present study…
Sharifdini, Meysam; Heidari, Zahra; Hesari, Zahra; Vatandoost, Sajad; Kia, Eshrat Beigom
2017-06-01
The present study was performed to analyze molecularly the phylogenetic positions of human-infecting Trichostrongylus species in Mazandaran Province, Iran, which is an endemic area for trichostrongyliasis. DNA from 7 Trichostrongylus infected stool samples were extracted by using in-house (IH) method. PCR amplification of ITS2-rDNA region was performed, and products were sequenced. Phylogenetic analysis of the nucleotide sequence data was performed using MEGA 5.0 software. Six out of 7 isolates had high similarity with Trichostrongylus colubriformis , while the other one showed high homology with Trichostrongylus axei registered in GenBank reference sequences. Intra-specific variations within isolates of T. colubriformis and T. axei amounted to 0-1.8% and 0-0.6%, respectively. Trichostrongylus species obtained in the present study were in a cluster with the relevant reference sequences from previous studies. BLAST analysis indicated that there was 100% homology among all 6 ITS2 sequences of T. colubriformis in the present study and most previously registered sequences of T. colubriformis from human, sheep, and goat isolates from Iran and also human isolates from Laos, Thailand, and France. The ITS2 sequence of T. axei exhibited 99.4% homology with the human isolate of T. axei from Thailand, sheep isolates from New Zealand and Iran, and cattle isolate from USA.
A Study of Failure Criteria of Fibrous Composite Materials
NASA Technical Reports Server (NTRS)
Paris, Federico; Jackson, Karen E. (Technical Monitor)
2001-01-01
The research described in this paper is focused on two areas: (1) evaluation of existing composite failure criteria in the nonlinear, explicit transient dynamic finite element code, MSC.Dytran, and (2) exploration of the possibilities for modification of material and failure models to account for large deformations, progressive failure, and interaction of damage accumulation with stress/strain response of laminated composites. Following a review of the MSC.Dytran user manual, a bibliographical review of existing failure criteria of composites was performed. The papers considered most interesting for the objective of this report are discussed in section 2. The failure criteria included in the code under consideration are discussed in section 3. A critical summary of the present procedures to perform analysis and design of composites is presented in section 4. A study of the most important historical failure criteria for fibrous composite materials and some of the more recent modifications proposed were studied. The result of this analysis highlighted inadequacies in the existing failure criteria and the need to perform some numerical analyses to elucidate the answer to questions on which some of the proposed criteria are based. A summary of these ideas, which is a proposal of studies to be developed, is presented in section 5. Finally, some ideas for future developments are summarized in section 6.
Validation of the human odor span task: effects of nicotine.
MacQueen, David A; Drobes, David J
2017-10-01
Amongst non-smokers, nicotine generally enhances performance on tasks of attention, with limited effect on working memory. In contrast, nicotine has been shown to produce robust enhancements of working memory in non-humans. To address this gap, the present study investigated the effects of nicotine on the performance of non-smokers on a cognitive battery which included a working memory task reverse-translated from use with rodents (the odor span task, OST). Nicotine has been reported to enhance OST performance in rats and the present study assessed whether this effect generalizes to human performance. Thirty non-smokers were tested on three occasions after consuming either placebo, 2 mg, or 4 mg nicotine gum. On each occasion, participants completed a battery of clinical and experimental tasks of working memory and attention. Nicotine was associated with dose-dependent enhancements in sustained attention, as evidenced by increased hit accuracy on the rapid visual information processing (RVIP) task. However, nicotine failed to produce main effects on OST performance or on alternative measures of working memory (digit span, spatial span, letter-number sequencing, 2-back) or attention (digits forward, 0-back). Interestingly, enhancement of RVIP performance occurred concomitant to significant reductions in self-reported attention/concentration. Human OST performance was significantly related to N-back performance, and as in rodents, OST accuracy declined with increasing memory load. Given the similarity of human and rodent OST performance under baseline conditions and the strong association between OST and visual 0-back accuracy, the OST may be particular useful in the study of conditions characterized by inattention.
Rewarded remembering: dissociations between self-rated motivation and memory performance.
Ngaosuvan, Leonard; Mäntylä, Timo
2005-08-01
People often claim that they perform better in memory performance tasks when they are more motivated. However, past research has shown minimal effects of motivation on memory performance when factors contributing to item-specific biases during encoding and retrieval are taken into account. The purpose of the present study was to examine the generality of this apparent dissociation by using more sensitive measures of experienced motivation and memory performance. Extrinsic motivation was manipulated through competition instructions, and subjective ratings of intrinsic and extrinsic motivation were obtained before and after study instructions. Participants studied a series of words, and memory performance was assessed by content recall (Experiment 1) and source recall (Experiment 2). Both experiments showed dissociation between subjective ratings of extrinsic motivation and actual memory performance, so that competition increased self-rated extrinsic motivation but had no effects on memory performance, including source recall. Inconsistent with most people's expectations, the findings suggest that extrinsic motivation has minimal effects on memory performance.
ERIC Educational Resources Information Center
Birchwood, James; Daley, Dave
2012-01-01
Less is understood about the relationship between ADHD symptoms and academic performance in adolescents than the relationship in younger children. As such, the aim of the present study was to investigate the prospective relationship between ADHD symptoms and academic performance in a community adolescent sample. Three hundred and twenty-four…
ERIC Educational Resources Information Center
Abrams, Zsuzsanna; Rott, Susanne
2017-01-01
Research on second language (L2) grammar in task-based language learning has yielded inconsistent results regarding the effects of task-complexity, prompting calls for more nuanced analyses of L2 development and task performance. The present cross-sectional study contributes to this discussion by comparing the performance of 245 learners of German…
ERIC Educational Resources Information Center
Benbenishty, Rami; Astor, Ron Avi; Roziner, Ilan; Wrabel, Stephani L.
2016-01-01
The present study explores the causal link between school climate, school violence, and a school's general academic performance over time using a school-level, cross-lagged panel autoregressive modeling design. We hypothesized that reductions in school violence and climate improvement would lead to schools' overall improved academic performance.…
ERIC Educational Resources Information Center
Thompson, Ted; Dinnel, Dale L.
2007-01-01
Self-worth protective students characteristically perform poorly when they anticipate that poor performance is likely to reveal low ability, yet perform well in situations that involve little threat to self-worth. The present study sought a further understanding of this variable pattern of achievement, assessing two possibilities: (1) that the…
ERIC Educational Resources Information Center
Norman, D. A.; And Others
"Machine controlled adaptive training is a promising concept. In adaptive training the task presented to the trainee varies as a function of how well he performs. In machine controlled training, adaptive logic performs a function analogous to that performed by a skilled operator." This study looks at the ways in which gain-effective time…
The Effects of Performance Feedback and Social Reinforcement on Up-Selling at Fast-Food Restaurants
ERIC Educational Resources Information Center
Wiesman, Daryl W.
2006-01-01
The present study sought to evaluate the effects of feedback and positive social reinforcement on the performance of restaurant drive-thru window order-takers in asking customers to "upsize" their order at a specific prompt. A multiple baseline across settings was followed by the introduction of an intervention of weekly performance feedback and…
WebQuests in Special Primary Education: Learning in a Web-Based Environment
ERIC Educational Resources Information Center
Kleemans, Tijs; Segers, Eliane; Droop, Mienke; Wentink, Hanneke
2011-01-01
The present study investigated the differences in learning gain when performing a WebQuest with a well-defined versus an ill-defined assignment. Twenty boys and twenty girls (mean age 11; 10), attending a special primary education school, performed two WebQuests. In each WebQuest, they performed either a well-defined or an ill-defined assignment.…
ERIC Educational Resources Information Center
Putwain, David W.; Aveyard, Ben
2018-01-01
A well established finding is that the cognitive component of test anxiety (worry) is negatively related to examination performance. The present study examined how 3 self-beliefs (academic buoyancy, perceived control, and test competence) moderated the strength of the relationship between worry and examination performance in a sample of 270 final…
ERIC Educational Resources Information Center
Van Impe, A.; Coxon, J. P.; Goble, D. J.; Wenderoth, N.; Swinnen, S. P.
2011-01-01
Depending on task combination, dual-tasking can either be performed successfully or can lead to performance decrements in one or both tasks. Interference is believed to be caused by limitations in central processing, i.e. structural interference between the neural activation patterns associated with each task. In the present study, single- and…
ERIC Educational Resources Information Center
Andreou, Georgia; Riga, Asimina; Papayiannis, Nikolaos
2016-01-01
The present study investigates whether the use of ICTs improves the writing performance of students with ADHD (Attention Deficit Hyperactivity Disorder). It also examines whether gender affects performance. A number of ADHD students were selected and were assessed for their use of a combination of distinct educational tools. Divided into two…
Age Differences in Strategic Planning as Indexed by the Tower of London
ERIC Educational Resources Information Center
Albert, Dustin; Steinberg, Laurence
2011-01-01
The present study examined age differences in performance on the Tower of London, a measure of strategic planning, in a diverse sample of 890 individuals between the ages of 10 and 30. Although mature performance was attained by age 17 on relatively easy problems, performance on the hardest problems showed improvements into the early 20s.…
ERIC Educational Resources Information Center
Pociask, Sarah; Gross, David; Shih, Mei-Yau
2017-01-01
The literature on team-based learning emphasizes the importance of team composition and team design, and it is recommended that instructors organize teams to ensure diversity of team members and optimal team performance. But does the method of team formation actually impact student performance? The goal of the present study was to examine whether…
ERIC Educational Resources Information Center
Sanchez Fowler, Laura T.; Banks, Tachelle I.; Anhalt, Karla; Der, Heidi Hinrichs; Kalis, Tara
2008-01-01
The present study examined the relation between teacher ratings of student social functioning and academic performance and teacher-student relationship quality. Data were collected from 230 students and 20 teachers in two high-poverty, low-performing schools in a large urban school district in the Midwest. Students were 93% African American.…
ERIC Educational Resources Information Center
Hung, Wei-Chen; Kalota, Faisal
2013-01-01
The importance of adopting technology-supported performance systems for on-the-job learning and training is well-recognized in a networked economy. In this study, we present a performance support system (PSS) designed to support technology integration for lesson design. The goal is to support educators in the development of appropriate and…
Ceschi, Andrea; Demerouti, Evangelia; Sartori, Riccardo; Weller, Joshua
2017-01-01
The present study aims to connect more the I/O and the decision-making psychological domains, by showing how some common components across jobs interfere with decision-making and affecting performance. Two distinct constructs that can contribute to positive workplace performance have been considered: decision-making competency (DMCy) and decision environment management (DEM). Both factors are presumed to involve self-regulatory mechanisms connected to decision processes by influencing performance in relation to work environment conditions. In the framework of the job demands-resources (JD-R) model, the present study tested how such components as job demands, job resources and exhaustion can moderate decision-making processes and performance, where high resources are advantageous for decision-making processes and performance at work, while the same effect happens with low job demands and/or low exhaustion. In line with the formulated hypotheses, results confirm the relations between both the decision-making competences, performance (i.e., in-role and extra-role) and moderators considered. In particular, employees with low levels of DMCy show to be more sensitive to job demands toward in-role performance, whereas high DEM levels increase the sensitivity of employees toward job resources and exhaustion in relation to extra-role performance. These findings indicate that decision-making processes, as well as work environment conditions, are jointly related to employee functioning. PMID:28529491
Ceschi, Andrea; Demerouti, Evangelia; Sartori, Riccardo; Weller, Joshua
2017-01-01
The present study aims to connect more the I/O and the decision-making psychological domains, by showing how some common components across jobs interfere with decision-making and affecting performance. Two distinct constructs that can contribute to positive workplace performance have been considered: decision-making competency (DMCy) and decision environment management (DEM). Both factors are presumed to involve self-regulatory mechanisms connected to decision processes by influencing performance in relation to work environment conditions. In the framework of the job demands-resources (JD-R) model, the present study tested how such components as job demands, job resources and exhaustion can moderate decision-making processes and performance, where high resources are advantageous for decision-making processes and performance at work, while the same effect happens with low job demands and/or low exhaustion. In line with the formulated hypotheses, results confirm the relations between both the decision-making competences, performance (i.e., in-role and extra-role) and moderators considered. In particular, employees with low levels of DMCy show to be more sensitive to job demands toward in-role performance, whereas high DEM levels increase the sensitivity of employees toward job resources and exhaustion in relation to extra-role performance. These findings indicate that decision-making processes, as well as work environment conditions, are jointly related to employee functioning.
Gong, Wontae
2015-01-01
[Purpose] The present study sought to investigate the influence on static and dynamic lumbar stability of bridge exercise accompanied by an abdominal drawing-in maneuver (ADIM) performed on an uneven support surface. [Subjects] A total of 30 participants were divided into an experimental group (15 participants) and a control group (15 participants). [Methods] The experimental group performed bridge exercise on an unstable surface, whereas the control group performed bridge exercise on a stable surface. The respective bridge exercises were performed for 30 minutes, 3 times per week, for 6 weeks. The static lumbar stability (SLS) and dynamic lumbar stability (DLS) of both the experimental group and the control group were measured using a pressure biofeedback unit. [Results] In the comparison of the initial and final results of the experimental and control groups, only the SLS and DLS of the experimental group were found to be statistically significant. [Conclusion] The results of the present study show that when using bridge exercise to improve SLS and DLS, performing the bridge exercise accompanied by ADIM on an uneven surface is more effective than performing the exercise on a stable surface.
Study of flow structure in a four-vortex furnace model
NASA Astrophysics Data System (ADS)
Anufriev, I. S.; Sharypov, O. V.; Dekterev, A. A.; Shadrin, E. Yu.; Papulov, A. P.
2017-11-01
The flow pattern was studied for a four-vortex furnace of a coal-dust boiler. The paper presents results of experimental study of inner aerodynamics performed on a lab-scale isothermal model of the furnace device. The PIV method was used to receive the flow velocity fields for several cross sections. The analysis was performed for the spatial structure of the flow comprising four stable closed vortices with vertical axes of flow swirling.
Plasma Chemistry Processes in the Closed Cycle EDL.
1979-07-01
chemistry. The present study is mainly concerned with plasma by-products and, to some degree, with initial impurities and their influence on laser...performance. The plasma chemistry important in the formation of these by-products has been studied in greatest detail for He/N 2 /C0 2 mixtures loaded by...cases for two closed cycle EDL devices currently under development. The study includes the effects on performance of variations in the electric field
Mobile-ip Aeronautical Network Simulation Study
NASA Technical Reports Server (NTRS)
Ivancic, William D.; Tran, Diepchi T.
2001-01-01
NASA is interested in applying mobile Internet protocol (mobile-ip) technologies to its space and aeronautics programs. In particular, mobile-ip will play a major role in the Advanced Aeronautic Transportation Technology (AATT), the Weather Information Communication (WINCOMM), and the Small Aircraft Transportation System (SATS) aeronautics programs. This report presents the results of a simulation study of mobile-ip for an aeronautical network. The study was performed to determine the performance of the transmission control protocol (TCP) in a mobile-ip environment and to gain an understanding of how long delays, handoffs, and noisy channels affect mobile-ip performance.
Carvalho, Brendan; Tan, Jonathan M; Macario, Alex; El-Sayed, Yasser Y; Sultan, Pervez
2013-07-01
In this study, we sought to determine whether neuraxial anesthesia to facilitate external cephalic version (ECV) increased delivery costs for breech fetal presentation. Using a computer cost model, which considers possible outcomes and probability uncertainties at the same time, we estimated total expected delivery costs for breech presentation managed by a trial of ECV with and without neuraxial anesthesia. From published studies, the average probability of successful ECV with neuraxial anesthesia was 60% (with individual studies ranging from 44% to 87%) compared with 38% (with individual studies ranging from 31% to 58%) without neuraxial anesthesia. The mean expected total delivery costs, including the cost of attempting/performing ECV with anesthesia, equaled $8931 (2.5th-97.5th percentile prediction interval $8541-$9252). The cost was $9207 (2.5th-97.5th percentile prediction interval $8896-$9419) if ECV was attempted/performed without anesthesia. The expected mean incremental difference between the total cost of delivery that includes ECV with anesthesia and ECV without anesthesia was $-276 (2.5th-97.5th percentile prediction interval $-720 to $112). The total cost of delivery in women with breech presentation may be decreased (up to $720) or increased (up to $112) if ECV is attempted/performed with neuraxial anesthesia compared with ECV without neuraxial anesthesia. Increased ECV success with neuraxial anesthesia and the subsequent reduction in breech cesarean delivery rate offset the costs of providing anesthesia to facilitate ECV.
Souchal, Carine; Toczek, Marie-Christine; Darnon, Céline; Smeding, Annique; Butera, Fabrizio; Martinot, Delphine
2014-03-01
Is it possible to reach performance equality between boys and girls in a science class? Given the stereotypes targeting their groups in scientific domains, diagnostic contexts generally lower girls' performance and non-diagnostic contexts may harm boys' performance. The present study tested the effectiveness of a mastery-oriented assessment, allowing both boys and girls to perform at an optimal level in a science class. Participants were 120 boys and 72 girls (all high-school students). Participants attended a science lesson while expecting a performance-oriented assessment (i.e., an assessment designed to compare and select students), a mastery-oriented assessment (i.e., an assessment designed to help students in their learning), or no assessment of this lesson. In the mastery-oriented assessment condition, both boys and girls performed at a similarly high level, whereas the performance-oriented assessment condition reduced girls' performance and the no-assessment condition reduced boys' performance. One way to increase girls' performance on a science test without harming boys' performance is to present assessment as a tool for improving mastery rather than as a tool for comparing performances. © 2013 The British Psychological Society.
ERIC Educational Resources Information Center
Llanes, Àngels; Tragant, Elsa; Serrano, Raquel
2018-01-01
The present study examines the effects that a 3-week study-abroad (SA) experience and a set of individual differences have on the foreign language (FL) development of a group of 64 Catalan/Spanish speakers, learners of English as an FL. Moreover, the present study attempts to account for the outcome differences between successful and less…
Contribution of variable-speed pump hydro storage for power system dynamic performance
NASA Astrophysics Data System (ADS)
Silva, B.; Moreira, C.
2017-04-01
This paper presents the study of variable-speed Pump Storage Powerplant (PSP) in the Portuguese power system. It evaluates the progressive integration in three major locations and compares the power system performance following a severe fault event with consequent disconnection of non-Fault Ride-through (FRT) compliant Wind Farms (WF). To achieve such objective, a frequency responsive model was developed in PSS/E and was further used to substitute existing fixed-speed PSP. The results allow identifying a clear enhancement on the power system performance by the presence of frequency responsive variable-speed PSP, especially for the scenario presented, with high level of renewables integration.
Simulator for concurrent processing data flow architectures
NASA Technical Reports Server (NTRS)
Malekpour, Mahyar R.; Stoughton, John W.; Mielke, Roland R.
1992-01-01
A software simulator capability of simulating execution of an algorithm graph on a given system under the Algorithm to Architecture Mapping Model (ATAMM) rules is presented. ATAMM is capable of modeling the execution of large-grained algorithms on distributed data flow architectures. Investigating the behavior and determining the performance of an ATAMM based system requires the aid of software tools. The ATAMM Simulator presented is capable of determining the performance of a system without having to build a hardware prototype. Case studies are performed on four algorithms to demonstrate the capabilities of the ATAMM Simulator. Simulated results are shown to be comparable to the experimental results of the Advanced Development Model System.
Simulation verification techniques study. Subsystem simulation validation techniques
NASA Technical Reports Server (NTRS)
Duncan, L. M.; Reddell, J. P.; Schoonmaker, P. B.
1974-01-01
Techniques for validation of software modules which simulate spacecraft onboard systems are discussed. An overview of the simulation software hierarchy for a shuttle mission simulator is provided. A set of guidelines for the identification of subsystem/module performance parameters and critical performance parameters are presented. Various sources of reference data to serve as standards of performance for simulation validation are identified. Environment, crew station, vehicle configuration, and vehicle dynamics simulation software are briefly discussed from the point of view of their interfaces with subsystem simulation modules. A detailed presentation of results in the area of vehicle subsystems simulation modules is included. A list of references, conclusions and recommendations are also given.
Roverud, Elin; Best, Virginia; Mason, Christine R; Streeter, Timothy; Kidd, Gerald
2017-12-15
The "visually guided hearing aid" (VGHA), consisting of a beamforming microphone array steered by eye gaze, is an experimental device being tested for effectiveness in laboratory settings. Previous studies have found that beamforming without visual steering can provide significant benefits (relative to natural binaural listening) for speech identification in spatialized speech or noise maskers when sound sources are fixed in location. The aim of the present study was to evaluate the performance of the VGHA in listening conditions in which target speech could switch locations unpredictably, requiring visual steering of the beamforming. To address this aim, the present study tested an experimental simulation of the VGHA in a newly designed dynamic auditory-visual word congruence task. Ten young normal-hearing (NH) and 11 young hearing-impaired (HI) adults participated. On each trial, three simultaneous spoken words were presented from three source positions (-30, 0, and 30 azimuth). An auditory-visual word congruence task was used in which participants indicated whether there was a match between the word printed on a screen at a location corresponding to the target source and the spoken target word presented acoustically from that location. Performance was compared for a natural binaural condition (stimuli presented using impulse responses measured on KEMAR), a simulated VGHA condition (BEAM), and a hybrid condition that combined lowpass-filtered KEMAR and highpass-filtered BEAM information (BEAMAR). In some blocks, the target remained fixed at one location across trials, and in other blocks, the target could transition in location between one trial and the next with a fixed but low probability. Large individual variability in performance was observed. There were significant benefits for the hybrid BEAMAR condition relative to the KEMAR condition on average for both NH and HI groups when the targets were fixed. Although not apparent in the averaged data, some individuals showed BEAM benefits relative to KEMAR. Under dynamic conditions, BEAM and BEAMAR performance dropped significantly immediately following a target location transition. However, performance recovered by the second word in the sequence and was sustained until the next transition. When performance was assessed using an auditory-visual word congruence task, the benefits of beamforming reported previously were generally preserved under dynamic conditions in which the target source could move unpredictably from one location to another (i.e., performance recovered rapidly following source transitions) while the observer steered the beamforming via eye gaze, for both young NH and young HI groups.
NASA Technical Reports Server (NTRS)
Morris, S. J., Jr.
1980-01-01
Performance estimations, weights, and scaling laws for the six blade and ten blade highly loaded propellers combined with an advanced turboshaft engine are presented. These data are useful for aircraft mission studies using the turboprop system. Comparisons are made between the performance of post 1980 technology turboprop propulsion systems and the performance of both a current technology turbofan and a post 1990 technology turbofan.
Students' Metacomprehension Knowledge: Components That Predict Comprehension Performance
ERIC Educational Resources Information Center
Zabrucky, Karen M.; Moore, DeWayne; Agler, Lin-Miao Lin; Cummings, Andrea M.
2015-01-01
In the present study, we assessed students' metacomprehension knowledge and examined the components of knowledge most related to comprehension of expository texts. We used the Revised Metacomprehension Scale (RMCS) to investigate the relations between students' metacomprehension knowledge and comprehension performance. Students who evaluated and…
Managerial Performance Issues. Symposium 24. [AHRD Conference, 2001].
ERIC Educational Resources Information Center
2001
This document contains three papers on managerial performance issues. "Managerial Skill Requirements: Evidence from the Scottish Visitor Attraction Industry" (Sandra Watson, Martin McCracken) presents the findings from an exploratory study of those skills that managers in the Scottish visitor attraction sector considered most important…
Predicting School Performance with the Early Screening Inventory.
ERIC Educational Resources Information Center
Meisels, Samuel J.; And Others
1984-01-01
Proposes criteria for defining and selecting preschool developmental screening instruments and describes the Early Screening Inventory (ESI), a developmental screening instrument designed to satisfy these criteria. Presents results of several studies demonstrating that the ESI predicts school performance with moderate to excellent accuracy through…
Personality and Performance in Intercollegiate Football.
ERIC Educational Resources Information Center
Garland, Daniel J.; Barry, John R.
The present study, based on Chelladurai and Carron's (1978) multidimensional theory of leadership, sought to determine if selected personality traits and specific leader behaviors are predictive of performance in collegiate football. Prior to regular season competition, collegiate football players (N=272) from three southeastern United States…
NASA Technical Reports Server (NTRS)
Braden, J. A.; Hancock, J. P.; Hackett, J. E.; Lyman, V.
1979-01-01
The experimental data encompassing surface pressure measurements, and wake surveys at static and wind-on conditions are analyzed. Cruise performance trends reflecting nacelle geometric variations, and nozzle operating conditions are presented. Details of the modeling process are included.
Statistics Anxiety, Trait Anxiety, Learning Behavior, and Academic Performance
ERIC Educational Resources Information Center
Macher, Daniel; Paechter, Manuela; Papousek, Ilona; Ruggeri, Kai
2012-01-01
The present study investigated the relationship between statistics anxiety, individual characteristics (e.g., trait anxiety and learning strategies), and academic performance. Students enrolled in a statistics course in psychology (N = 147) filled in a questionnaire on statistics anxiety, trait anxiety, interest in statistics, mathematical…
Kong, Jin-Liang; Luo, Jing; Li, Bing; Dong, Bi-Ying; Huang, Hong; Wang, Ke; Wu, Li-Hong; Chen, Yi-Qiang
2017-06-01
Aspergillus ( A .) fumigatus , one of the most common causes of life-threatening fungal infections in immunocompromised patients, shows resistance to antifungal agents as has a high propensity to forming a biofilm. The present study aimed to investigate the effects of chlorogenic acid (CRA) on A. fumigatus biofilm formation and integrity. Confocal laser scanning microscopy was performed to determine the inhibitory effects of CRA against A. fumigatus biofilm formation. Transmission electron microscopy was performed to investigate the ultrastructural changes of A. fumigatus biofilm after CRA exposure. High-performance liquid chromatography and reverse-transcription quantitative PCR were performed to determine the expression of gliotoxin production in biofilm culture. The results showed that CRA at sub-minimum inhibitory concentrations inhibited A. fumigatus biofilm formation. In addition, CRA could decreased the gliotoxin production in the biofilm culture supernatant through inhibiting the expression of master genes involved in gliotoxin biosynthesis. The present study provided useful information for the development of novel strategies to reduce the incidence of A. fumigatus biofilm-associated diseases.
Sim, L; Manthey, K; Stuckey, S
2007-06-01
A study to compare performance of the following display monitors for application as PACS CR diagnostic workstations is described. 1. Diagnostic quality, 3 Mega Pixel, 21 inch monochrome LCD monitors--Planar C3i. 2. Clinical review quality, 2 Mega Pixel, 21 inch colour LCD monitors--Planar PX212. Two sets of seventy radiological studies were presented to four senior radiologists on two occasions, using different displays on each occasion. The clinical condition used for this investigation was to query for the presence of a solitary pulmonary nodule. Receiver Operating Characteristic (ROC) curves were constructed for diagnostic performance for each presentation. Areas under the ROC curves (AUC) for diagnosis using different monitors were compared and the following results obtained: Monochrome AUC = 0.813 +/- 0.02, Colour AUC = 0.801 +/- 0.021. These results indicate that there is no statistically significant difference in the performance of these monitor types at a 95% confidence level.
Sander, Uwe; Emmert, Martin; Dickel, Jochen; Meszmer, Nina; Kolb, Benjamin
2015-03-16
Improving the transparency of information about the quality of health care providers is one way to improve health care quality. It is assumed that Internet information steers patients toward better-performing health care providers and will motivate providers to improve quality. However, the effect of public reporting on hospital quality is still small. One of the reasons is that users find it difficult to understand the formats in which information is presented. We analyzed the presentation of risk-adjusted mortality rate (RAMR) for coronary angiography in the 10 most commonly used German public report cards to analyze the impact of information presentation features on their comprehensibility. We wanted to determine which information presentation features were utilized, were preferred by users, led to better comprehension, and had similar effects to those reported in evidence-based recommendations described in the literature. The study consisted of 5 steps: (1) identification of best-practice evidence about the presentation of information on hospital report cards; (2) selection of a single risk-adjusted quality indicator; (3) selection of a sample of designs adopted by German public report cards; (4) identification of the information presentation elements used in public reporting initiatives in Germany; and (5) an online panel completed an online questionnaire that was conducted to determine if respondents were able to identify the hospital with the lowest RAMR and if respondents' hospital choices were associated with particular information design elements. Evidence-based recommendations were made relating to the following information presentation features relevant to report cards: evaluative table with symbols, tables without symbols, bar charts, bar charts without symbols, bar charts with symbols, symbols, evaluative word labels, highlighting, order of providers, high values to indicate good performance, explicit statements of whether high or low values indicate good performance, and incomplete data ("N/A" as a value). When investigating the RAMR in a sample of 10 hospitals' report cards, 7 of these information presentation features were identified. Of these, 5 information presentation features improved comprehensibility in a manner reported previously in literature. To our knowledge, this is the first study to systematically analyze the most commonly used public reporting card designs used in Germany. Best-practice evidence identified in international literature was in agreement with 5 findings about German report card designs: (1) avoid tables without symbols, (2) include bar charts with symbols, (3) state explicitly whether high or low values indicate good performance or provide a "good quality" range, (4) avoid incomplete data (N/A given as a value), and (5) rank hospitals by performance. However, these findings are preliminary and should be subject of further evaluation. The implementation of 4 of these recommendations should not present insurmountable obstacles. However, ranking hospitals by performance may present substantial difficulties.
VSCE technology definition study
NASA Technical Reports Server (NTRS)
Howlett, R. A.; Hunt, R. B.
1979-01-01
Refined design definition of the variable stream control engine (VSCE) concept for advanced supersonic transports is presented. Operating and performance features of the VSCE are discussed, including the engine components, thrust specific fuel consumption, weight, noise, and emission system. A preliminary engine design is presented.
Performance evaluation capabilities for the design of physical systems
NASA Technical Reports Server (NTRS)
Pilkey, W. D.; Wang, B. P.
1972-01-01
The results are presented of a study aimed at developing and formulating a capability for the limiting performance of large steady state systems. The accomplishments reported include: (1) development of a theory of limiting performance of large systems subject to steady state inputs; (2) application and modification of PERFORM, the computational capability for the limiting performance of systems with transient inputs; and (3) demonstration that use of an inherently smooth control force for a limiting performance calculation improves the system identification phase of the design process for physical systems subjected to transient loading.
Buchheit, Martin; Mendez-Villanueva, Alberto
2014-01-01
The aim of the present study was to compare, in 36 highly trained under-15 soccer players, the respective effects of age, maturity and body dimensions on match running performance. Maximal sprinting (MSS) and aerobic speeds were estimated. Match running performance was analysed with GPS (GPSport, 1 Hz) during 19 international friendly games (n = 115 player-files). Total distance and distance covered >16 km h(-1) (D > 16 km h(-1)) were collected. Players advanced in age and/or maturation, or having larger body dimensions presented greater locomotor (Cohen's d for MSS: 0.5-1.0, likely to almost certain) and match running performances (D > 16 km h(-1): 0.2-0.5, possibly to likely) than their younger, less mature and/or smaller teammates. These age-, maturation- and body size-related differences were of larger magnitude for field test measures versus match running performance. Compared with age and body size (unclear to likely), maturation (likely to almost certainly for all match variables) had the greatest impact on match running performance. The magnitude of the relationships between age, maturation and body dimensions and match running performance were position-dependent. Within a single age-group in the present player sample, maturation had a substantial impact on match running performance, especially in attacking players. Coaches may need to consider players' maturity status when assessing their on-field playing performance.
Physiological Parameter Response to Variation of Mental Workload.
Marinescu, Adrian Cornelius; Sharples, Sarah; Ritchie, Alastair Campbell; Sánchez López, Tomas; McDowell, Michael; Morvan, Hervé P
2018-02-01
To examine the relationship between experienced mental workload and physiological response by noninvasive monitoring of physiological parameters. Previous studies have examined how individual physiological measures respond to changes in mental demand and subjective reports of workload. This study explores the response of multiple physiological parameters and quantifies their added value when estimating the level of demand. The study presented was conducted in laboratory conditions and required participants to perform a visual-motor task that imposed varying levels of demand. The data collected consisted of physiological measurements (heart interbeat intervals, breathing rate, pupil diameter, facial thermography), subjective ratings of workload (Instantaneous Self-Assessment Workload Scale [ISA] and NASA-Task Load Index), and the performance. Facial thermography and pupil diameter were demonstrated to be good candidates for noninvasive workload measurements: For seven out of 10 participants, pupil diameter showed a strong correlation ( R values between .61 and .79 at a significance value of .01) with mean ISA normalized values. Facial thermography measures added on average 47.7% to the amount of variability in task performance explained by a regression model. As with the ISA ratings, the relationship between the physiological measures and performance showed strong interparticipant differences, with some individuals demonstrating a much stronger relationship between workload and performance measures than others. The results presented in this paper demonstrate that physiological and pupil diameter can be used for noninvasive real-time measurement of workload. The methods presented in this article, with current technological capabilities, are better suited for workplaces where the person is seated, offering the possibility of being applied to pilots and air traffic controllers.
Effects of caffeine and alcohol on mood and performance changes following consumption of lager.
Smith, Andrew P
2013-06-01
The present study examined whether caffeine would modify the behavioural effects of alcohol. The aim of the study was to determine whether caffeine modifies the effects of alcohol on mood and psychomotor performance and to identify possible dose-response and temporal relationships. A double-blind study examined the effects of three successive lager drinks (330 ml each) in the early afternoon on mood and psychomotor performance assessed at 30-min intervals over a 2-h period. Participants carried out a baseline session and were then randomly assigned to one of six conditions formed by combining three different doses of caffeine (0, 62.5 and 125 mg per drink) with either no alcohol or 4.3 % alcohol. One hundred and forty-six young adults (65 male, 81 female; age range 18-30 years) participated in the study. Mood (alertness, hedonic tone and anxiety) was assessed before and after performing simple reaction time and choice reaction time tasks. Alcohol was associated with higher hedonic tone (p < 0.005), reduced anxiety (p < 0.05) and reduced alertness (p < 0.005). Caffeine had no modifying effect on hedonic tone or anxiety. However, the highest dose of caffeine did remove the effect of alcohol on alertness (p < 0.05). Effects of alcohol and caffeine were found on the performance tasks (all p values < 0.05) but these were independent effects. The results from the present study confirm that caffeine does not remove the negative effects of alcohol on performance although high doses counteract the drop in subjective alertness produced by alcohol.
Ittig, S; Studerus, E; Papmeyer, M; Uttinger, M; Koranyi, S; Ramyead, A; Riecher-Rössler, A
2015-02-01
Several sex differences in schizophrenia have been reported including differences in cognitive functioning. Studies with schizophrenia patients and healthy controls (HC) indicate that the sex advantage for women in verbal domains is also present in schizophrenia patients. However, findings have been inconsistent. No study focused on sex-related cognitive performance differences in at-risk mental state for psychosis (ARMS) individuals yet. Thus, the aim of the present study was to investigate sex differences in cognitive functioning in ARMS, first episode psychosis (FEP) and HC subjects. We expected a better verbal learning and memory performance of women in all groups. The neuropsychological data analysed in this study were collected within the prospective Früherkennung von Psychosen (FePsy) study. In total, 118 ARMS, 88 FEP individuals and 86 HC completed a cognitive test battery covering the domains of executive functions, attention, working memory, verbal learning and memory, IQ and speed of processing. Women performed better in verbal learning and memory regardless of diagnostic group. By contrast, men as compared to women showed a shorter reaction time during the working memory task across all groups. The results provide evidence that women generally perform better in verbal learning and memory, independent of diagnostic group (ARMS, FEP, HC). The finding of a shorter reaction time for men in the working memory task could indicate that men have a superior working memory performance since they responded faster during the target trials, while maintaining a comparable overall working memory performance level. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
The role of vision in academic school performance.
Dirani, Mohamed; Zhang, Xiaoe; Goh, Liang Ke; Young, Terri L; Lee, Paul; Saw, Seang Mei
2010-01-01
To determine whether presenting distance visual acuity is related to subsequent academic school performance in Singaporean children between 9 to 10 years of age. Singapore children (n = 1143 children) were examined during their visits at ages 9 to 10 years (grades 3 to 4) as part of the Singapore Cohort Study of the Risk Factors for Myopia (SCORM) longitudinal study. Each child underwent an annual comprehensive eye examination, including the assessment of presenting logarithm of the minimum angle of resolution (LogMAR) distance visual acuity (VA). The individual marks of a nation-wide standard examination in grade 4 were used as the outcome measure for academic school performance. Children with any known eye disease, (such as media opacities) were excluded from the analysis. The mean presenting distance VA of the better eye was 0.10 and 0.08 when the children were in grades 3 and 4, respectively. There was a statistically significant difference for mean presenting VA with 9 and 10 year old boys scoring better (0.08 and 0.07) compared to girls (0.12 and 0.09) for the same ages, (p = 0.001 and p = 0.007), respectively. After adjusting for gender, ethnicity, school, reading, intelligence quotient and father's education, no significant relationships were found between average examination marks at the end of grade 4 and presenting VA obtained (better eye and worst eye) in grade 3 (p = 0.38 and p = 0.98) and 4 (p = 0.27 and p = 0.16). In our sample of Singaporean children without ocular disease, distance VA did not play a significant role in predicting academic school performance.
Performable Case Studies in Ethics Education.
Robeson, Richard; King, Nancy M P
2017-09-12
Bioethics education often includes the study of short stories, novels, plays, and films, because such materials present case examples that can highlight relevant issues and questions especially vividly for a wide range of students. In addition, creative writing is widely used in the education of health professional students and in continuing education settings for health professionals. There are very few academic or professional disciplines that do not use case studies, but the case study in dialogic form has not been standard practice for thousands of years. Dramatic arts casuistry-the creation and performance of short case studies designed specifically to raise bioethics issues for discussion-represents an application of literature and the medical humanities that is both unique and uniquely valuable. This essay describes the development and history of a course that has been successfully taught to medical students and graduate bioethics students, in which the class researches, writes, and performs a case study designed to elicit reflection and discussion about a topic and set of bioethics issues of current interest to both academic and general audiences. The model is also suited to the presentation and discussion of existing case studies, both live and via on-demand audio.
Performable Case Studies in Ethics Education
Robeson, Richard; King, Nancy M. P.
2017-01-01
Bioethics education often includes the study of short stories, novels, plays, and films, because such materials present case examples that can highlight relevant issues and questions especially vividly for a wide range of students. In addition, creative writing is widely used in the education of health professional students and in continuing education settings for health professionals. There are very few academic or professional disciplines that do not use case studies, but the case study in dialogic form has not been standard practice for thousands of years. Dramatic arts casuistry—the creation and performance of short case studies designed specifically to raise bioethics issues for discussion—represents an application of literature and the medical humanities that is both unique and uniquely valuable. This essay describes the development and history of a course that has been successfully taught to medical students and graduate bioethics students, in which the class researches, writes, and performs a case study designed to elicit reflection and discussion about a topic and set of bioethics issues of current interest to both academic and general audiences. The model is also suited to the presentation and discussion of existing case studies, both live and via on-demand audio. PMID:28895903
Low-thrust chemical rocket engine study
NASA Technical Reports Server (NTRS)
Mellish, J. A.
1981-01-01
Engine data and information are presented to perform system studies on cargo orbit-transfer vehicles which would deliver large space structures to geosynchronous equatorial orbit. Low-thrust engine performance, weight, and envelope parametric data were established, preliminary design information was generated, and technologies for liquid rocket engines were identified. Two major engine design drivers were considered in the study: cooling and engine cycle options. Both film-cooled and regeneratively cooled engines were evaluated. The propellant combinations studied were hydrogen/oxygen, methane/oxygen, and kerosene/oxygen.