ERIC Educational Resources Information Center
Council of Chief State School Officers, Washington, DC.
This paper presents proceedings from a 2001 working conference of the State and District Support to Low-Performing Schools initiative, which presented research-based strategies and exemplary practice to improve low-performing schools. The presentations focused on state and district systems of support to low-performing schools; use of data to…
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.…
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.
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
Tao, Duoduo; Deng, Rui; Jiang, Ye; Galvin, John J; Fu, Qian-Jie; Chen, Bing
2014-01-01
To investigate how auditory working memory relates to speech perception performance by Mandarin-speaking cochlear implant (CI) users. Auditory working memory and speech perception was measured in Mandarin-speaking CI and normal-hearing (NH) participants. Working memory capacity was measured using forward digit span and backward digit span; working memory efficiency was measured using articulation rate. Speech perception was assessed with: (a) word-in-sentence recognition in quiet, (b) word-in-sentence recognition in speech-shaped steady noise at +5 dB signal-to-noise ratio, (c) Chinese disyllable recognition in quiet, (d) Chinese lexical tone recognition in quiet. Self-reported school rank was also collected regarding performance in schoolwork. There was large inter-subject variability in auditory working memory and speech performance for CI participants. Working memory and speech performance were significantly poorer for CI than for NH participants. All three working memory measures were strongly correlated with each other for both CI and NH participants. Partial correlation analyses were performed on the CI data while controlling for demographic variables. Working memory efficiency was significantly correlated only with sentence recognition in quiet when working memory capacity was partialled out. Working memory capacity was correlated with disyllable recognition and school rank when efficiency was partialled out. There was no correlation between working memory and lexical tone recognition in the present CI participants. Mandarin-speaking CI users experience significant deficits in auditory working memory and speech performance compared with NH listeners. The present data suggest that auditory working memory may contribute to CI users' difficulties in speech understanding. The present pattern of results with Mandarin-speaking CI users is consistent with previous auditory working memory studies with English-speaking CI users, suggesting that the lexical importance of voice pitch cues (albeit poorly coded by the CI) did not influence the relationship between working memory and speech perception.
Conceptual frameworks of individual work performance: a systematic review.
Koopmans, Linda; Bernaards, Claire M; Hildebrandt, Vincent H; Schaufeli, Wilmar B; de Vet Henrica, C W; van der Beek, Allard J
2011-08-01
Individual work performance is differently conceptualized and operationalized in different disciplines. The aim of the current review was twofold: (1) identifying conceptual frameworks of individual work performance and (2) integrating these to reach a heuristic conceptual framework. A systematic review was conducted in medical, psychological, and management databases. Studies were selected independently by two researchers and included when they presented a conceptual framework of individual work performance. A total of 17 generic frameworks (applying across occupations) and 18 job-specific frameworks (applying to specific occupations) were identified. Dimensions frequently used to describe individual work performance were task performance, contextual performance, counterproductive work behavior, and adaptive performance. On the basis of the literature, a heuristic conceptual framework of individual work performance was proposed. This framework can serve as a theoretical basis for future research and practice.
NASA Technical Reports Server (NTRS)
Holden, Kritina L.; Thompson, Shelby G.; Sandor, Aniko; McCann, Robert S.; Kaiser, Mary K.; Adelstein, Barnard D.; Begault, Durand R.; Beutter, Brent R.; Stone, Leland S.; Godfroy, Martine
2009-01-01
The goal of the Information Presentation Directed Research Project (DRP) is to address design questions related to the presentation of information to the crew. In addition to addressing display design issues associated with information formatting, style, layout, and interaction, the Information Presentation DRP is also working toward understanding the effects of extreme environments encountered in space travel on information processing. Work is also in progress to refine human factors-based design tools, such as human performance modeling, that will supplement traditional design techniques and help ensure that optimal information design is accomplished in the most cost-efficient manner. The major areas of work, or subtasks, within the Information Presentation DRP for FY10 are: 1) Displays, 2) Controls, 3) Procedures and Fault Management, and 4) Human Performance Modeling. The poster will highlight completed and planned work for each subtask.
Work Engagement: Antecedents, the Mediating Role of Learning Goal Orientation and Job Performance
ERIC Educational Resources Information Center
Chughtai, Aamir Ali; Buckley, Finian
2011-01-01
Purpose: The present paper aims to explore the effects of state (trust in supervisor) and trait (trust propensity) trust on employees' work engagement. Furthermore, it seeks to investigate the mediating role of learning goal orientation in the relationship between work engagement and two forms of performance: in-role job performance and innovative…
Work Engagement, Performance, and Active Learning: The Role of Conscientiousness
ERIC Educational Resources Information Center
Bakker, Arnold B.; Demerouti, Evangelia; ten Brummelhuis, Lieke L.
2012-01-01
The present study examines whether the relationship between work engagement and job performance is moderated by the extent to which individuals are inclined to work hard, careful, and goal-oriented. On the basis of the literature, it was hypothesized that conscientiousness strengthens the relationship between work engagement and supervisor ratings…
Relationship between meaningful work and job performance in nurses.
Tong, Ling
2018-04-01
The present study was designed to determine the relationship between meaningful work and job performance, and the impact of meaningful work on nursing care quality. Meaningful work has been suggested as a significant factor affecting job performance, but the relationship has never been studied in nurses in China. A descriptive correlational study was designed to assess the level of meaningful work, tasks, and contextual performance as well as their relationships. We used a stratified random-sampling approach to enrol nurses from hospitals. Multivariate regression analysis was applied to determine the relationship between meaningful work and their demographic data. There were significant, positive relationships between meaningful work and task performance and contextual performance. Education level, work unit, and employment type influenced meaningful work. The work motivation score of the nurses was lower than that of the other 2 dimensions, and a negative work motivation score negatively influenced job performance. Improving meaningful work and providing more support and assistance could improve nurse performance, thereby improving the quality of nursing care. © 2018 John Wiley & Sons Australia, Ltd.
[Influence of Nurses' Self-leadership on Individual and Team Members' Work Role Performance].
Kim, Se Young; Kim, Eun Kyung; Kim, Byungsoo; Lee, Eunpyo
2016-06-01
The purpose of this study was to examine correlations between nurses' self-leadership and individual work role performance and correlations between self-leadership in nursing units and team members' work role performance. Participants were 202 conveniently selected general nurses from 5 general hospitals in Korea. The study was carried out on 35 nursing units. Data were collected during February 2015 with self-report questionnaires. For factors affecting individual work role performance, self-expectation, self-goal setting, constructive thought, clinical career in the present nursing unit and marital status accounted for 44.0% of proficiency, while self-expectation, self-goal setting, constructive thought, and marital status accounted for 42.3% of adaptivity. Self-expectation, self-goal setting, constructive thought, self-reward, clinical career in the present nursing unit and position accounted for 26.4% of proactivity. In terms of team members' work role performance, self-reward and self-expectation in nursing units explained 29.0% of team members' proficiency. Self-reward and self-expectation in nursing units explained 31.6% of team members' adaptivity, and self-reward in nursing units explained 16.8% of team members' proactivity. The results confirm that nurses' self-leadership affects not only individual self-leadership but also team members' work role performance. Accordingly, to improve nurses' work role performance in nursing units of nursing organizations, improvement in nursing environment based on self-leadership education is necessary and nurses' tasks rearranged so they can appreciate work-autonomy and challenges of work.
Multiple social identities and stereotype threat: imbalance, accessibility, and working memory.
Rydell, Robert J; McConnell, Allen R; Beilock, Sian L
2009-05-01
In 4 experiments, the authors showed that concurrently making positive and negative self-relevant stereotypes available about performance in the same ability domain can eliminate stereotype threat effects. Replicating past work, the authors demonstrated that introducing negative stereotypes about women's math performance activated participants' female social identity and hurt their math performance (i.e., stereotype threat) by reducing working memory. Moving beyond past work, it was also demonstrated that concomitantly presenting a positive self-relevant stereotype (e.g., college students are good at math) increased the relative accessibility of females' college student identity and inhibited their gender identity, eliminating attendant working memory deficits and contingent math performance decrements. Furthermore, subtle manipulations in questions presented in the demographic section of a math test eliminated stereotype threat effects that result from women reporting their gender before completing the test. This work identifies the motivated processes through which people's social identities became active in situations in which self-relevant stereotypes about a stigmatized group membership and a nonstigmatized group membership were available. In addition, it demonstrates the downstream consequences of this pattern of activation on working memory and performance. Copyright (c) 2009 APA, all rights reserved.
Image processing for flight crew enhanced situation awareness
NASA Technical Reports Server (NTRS)
Roberts, Barry
1993-01-01
This presentation describes the image processing work that is being performed for the Enhanced Situational Awareness System (ESAS) application. Specifically, the presented work supports the Enhanced Vision System (EVS) component of ESAS.
Konecky, R O; Smith, M A; Olson, C R
2017-06-01
To explore the brain mechanisms underlying multi-item working memory, we monitored the activity of neurons in the dorsolateral prefrontal cortex while macaque monkeys performed spatial and chromatic versions of a Sternberg working-memory task. Each trial required holding three sequentially presented samples in working memory so as to identify a subsequent probe matching one of them. The monkeys were able to recall all three samples at levels well above chance, exhibiting modest load and recency effects. Prefrontal neurons signaled the identity of each sample during the delay period immediately following its presentation. However, as each new sample was presented, the representation of antecedent samples became weak and shifted to an anomalous code. A linear classifier operating on the basis of population activity during the final delay period was able to perform at approximately the level of the monkeys on trials requiring recall of the third sample but showed a falloff in performance on trials requiring recall of the first or second sample much steeper than observed in the monkeys. We conclude that delay-period activity in the prefrontal cortex robustly represented only the most recent item. The monkeys apparently based performance of this classic working-memory task on some storage mechanism in addition to the prefrontal delay-period firing rate. Possibilities include delay-period activity in areas outside the prefrontal cortex and changes within the prefrontal cortex not manifest at the level of the firing rate. NEW & NOTEWORTHY It has long been thought that items held in working memory are encoded by delay-period activity in the dorsolateral prefrontal cortex. Here we describe evidence contrary to that view. In monkeys performing a serial multi-item working memory task, dorsolateral prefrontal neurons encode almost exclusively the identity of the sample presented most recently. Information about earlier samples must be encoded outside the prefrontal cortex or represented within the prefrontal cortex in a cryptic code. Copyright © 2017 the American Physiological Society.
Titova, Olga E; Lindberg, Eva; Elmståhl, Sölve; Lind, Lars; Schiöth, Helgi B; Benedict, Christian
2016-09-01
Shift work has been proposed to promote cognitive disturbances in humans; however, conflicting evidence is also present. By using data from 7143 middle-aged and elderly humans (45-75 years) who participated in the Swedish EpiHealth cohort study, the present analysis sought to investigate whether self-reported shift work history would be associated with performance on the trail making test (TMT). The TMT has been proposed to be a useful neuropsychological tool to evaluate humans' executive cognitive function, which is known to decrease with age. After adjustment for potential confounders (e.g., age, education, and sleep duration), it was observed that current and recent former shift workers (worked shifts during the past 5 years) performed worse on the TMT than nonshift workers. In contrast, performance on the TMT did not differ between past shift workers (off from shift work for more than 5 years) and nonshift workers. Collectively, our results indicate that shift work history is linked to poorer performance on the TMT in a cohort of middle-aged and elderly humans. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.
The Effects of an Afterschool Physical Activity Program on Working Memory in Preadolescent Children
ERIC Educational Resources Information Center
Kamijo, Keita; Pontifex, Matthew B.; O'Leary, Kevin C.; Scudder, Mark R.; Wu, Chien-Ting; Castelli, Darla M.; Hillman, Charles H.
2011-01-01
The present study examined the effects of a 9-month randomized control physical activity intervention aimed at improving cardiorespiratory fitness on changes in working memory performance in preadolescent children relative to a waitlist control group. Participants performed a modified Sternberg task, which manipulated working memory demands based…
Constellation X-Ray Mission and Support
NASA Technical Reports Server (NTRS)
Tananbaum, H.; Grady, Jean (Technical Monitor)
2005-01-01
This Final Report summarizes work performed by the Smithsonian Astrophysical Observatory (SAO) for NASA Goddard Space Flight Center (GSFC) under Cooperative Agreement NCC5-368. The Agreement is entitled "Constellation X-ray Mission Study and Support." The report covers the full duration of the Agreement which ran from October 1,1998 to October 14,2004. Included in the report is a description of previously unreported work that was performed between October 2003 and the end of the Agreement. For convenience, the previously unreported work is covered first in Section 2.0. Then, an overall summary of all work performed under the Agreement is presented in Section 3. Section 4.0 contains a list of all formal reports that SAO has submitted to GSFC along with publications and presentations at various conferences.
Piccardi, L; Nori, R; Boccia, M; Barbetti, S; Verde, P; Guariglia, C; Ferlazzo, F
2015-08-01
In the present study, we used single- and dual-task conditions to investigate the nature of topographical working memory to better understand what type of task can hamper performance during navigation. During dual-task conditions, we considered four different sources of interference: motor (M), spatial motor (SM), verbal (i.e. articulatory suppression AS) and spatial environmental (SE). In order to assess the nature of topographical working memory, we used the Walking Corsi Test, asking the participants to perform two tasks simultaneously (M, SM, AS and SE). Our results showed that only spatial-environmental interference hampers the execution of a topographical working memory task, suggesting a task-domain-specific effect. We also found general gender differences in the topographical working memory capabilities: men were more proficient than women, regardless of the type of interferences. However, like men, women performed worse when a spatial-environmental interference was present.
D'Antuono, Giovanni; La Torre, Francesca Romana; Marin, Dario; Antonucci, Gabriella; Piccardi, Laura; Guariglia, Cecilia
2017-01-01
We investigated the relationship between verbal and visuo-spatial measures of working memory, inhibition, fluid intelligence and the performance on the Tower of London (ToL) task in a large sample of 830 healthy participants aged between 18 and 71 years. We found that fluid intelligence and visuo-spatial working memory accounted for a significant variance in the ToL task, while performances on verbal working memory and on the Stroop Test were not predictive for performance on the ToL. The present results confirm that fluid intelligence has a fundamental role on planning tests, but also show that visuo-spatial working memory plays a crucial role in ToL performance.
NASA Astrophysics Data System (ADS)
Choi, Jongseong
The performance of a hypersonic flight vehicle will depend on existing materials and fuels; this work presents the performance of the ideal scramjet engine for three different combustion chamber materials and three different candidate fuels. Engine performance is explored by parametric cycle analysis for the ideal scramjet as a function of material maximum service temperature and the lower heating value of jet engine fuels. The thermodynamic analysis is based on the Brayton cycle as similarly employed in describing the performance of the ramjet, turbojet, and fanjet ideal engines. The objective of this work is to explore material operating temperatures and fuel possibilities for the combustion chamber of a scramjet propulsion system to show how they relate to scramjet performance and the seven scramjet engine parameters: specific thrust, fuel-to-air ratio, thrust-specific fuel consumption, thermal efficiency, propulsive efficiency, overall efficiency, and thrust flux. The information presented in this work has not been done by others in the scientific literature. This work yields simple algebraic equations for scramjet performance which are similar to that of the ideal ramjet, ideal turbojet and ideal turbofan engines.
BESIII physical offline data analysis on virtualization platform
NASA Astrophysics Data System (ADS)
Huang, Q.; Li, H.; Kan, B.; Shi, J.; Lei, X.
2015-12-01
In this contribution, we present an ongoing work, which aims at benefiting BESIII computing system for higher resource utilization and more efficient job operations brought by cloud and virtualization technology with Openstack and KVM. We begin with the architecture of BESIII offline software to understand how it works. We mainly report the KVM performance evaluation and optimization from various factors in hardware and kernel. Experimental results show the CPU performance penalty of KVM can be approximately decreased to 3%. In addition, the performance comparison between KVM and physical machines in aspect of CPU, disk IO and network IO is also presented. Finally, we present our development work, an adaptive cloud scheduler, which allocates and reclaims VMs dynamically according to the status of TORQUE queue and the size of resource pool to improve resource utilization and job processing efficiency.
Initial Kernel Timing Using a Simple PIM Performance Model
NASA Technical Reports Server (NTRS)
Katz, Daniel S.; Block, Gary L.; Springer, Paul L.; Sterling, Thomas; Brockman, Jay B.; Callahan, David
2005-01-01
This presentation will describe some initial results of paper-and-pencil studies of 4 or 5 application kernels applied to a processor-in-memory (PIM) system roughly similar to the Cascade Lightweight Processor (LWP). The application kernels are: * Linked list traversal * Sun of leaf nodes on a tree * Bitonic sort * Vector sum * Gaussian elimination The intent of this work is to guide and validate work on the Cascade project in the areas of compilers, simulators, and languages. We will first discuss the generic PIM structure. Then, we will explain the concepts needed to program a parallel PIM system (locality, threads, parcels). Next, we will present a simple PIM performance model that will be used in the remainder of the presentation. For each kernel, we will then present a set of codes, including codes for a single PIM node, and codes for multiple PIM nodes that move data to threads and move threads to data. These codes are written at a fairly low level, between assembly and C, but much closer to C than to assembly. For each code, we will present some hand-drafted timing forecasts, based on the simple PIM performance model. Finally, we will conclude by discussing what we have learned from this work, including what programming styles seem to work best, from the point-of-view of both expressiveness and performance.
The Effects of Working Memory on Brain-Computer Interface Performance
Sprague, Samantha A.; McBee, Matthew; Sellers, Eric W.
2015-01-01
Objective The purpose of the present study is to evaluate the relationship between working memory and BCI performance. Methods Participants took part in two separate sessions. The first session consisted of three computerized tasks. The LSWM was used to measure working memory, the TPVT was used to measure general intelligence, and the DCCS was used to measure executive function, specifically cognitive flexibility. The second session consisted of a P300-based BCI copy-spelling task. Results The results indicate that both working memory and general intelligence are significant predictors of BCI performance. Conclusions This suggests that working memory training could be used to improve performance on a BCI task. Significance Working memory training may help to reduce a portion of the individual differences that exist in BCI performance allowing for a wider range of users to successfully operate the BCI system as well as increase the BCI performance of current users. PMID:26620822
Magnuson, Matthew Evan; Thompson, Garth John; Schwarb, Hillary; Pan, Wen-Ju; McKinley, Andy; Schumacher, Eric H; Keilholz, Shella Dawn
2015-12-01
The brain is organized into networks composed of spatially separated anatomical regions exhibiting coherent functional activity over time. Two of these networks (the default mode network, DMN, and the task positive network, TPN) have been implicated in the performance of a number of cognitive tasks. To directly examine the stable relationship between network connectivity and behavioral performance, high temporal resolution functional magnetic resonance imaging (fMRI) data were collected during the resting state, and behavioral data were collected from 15 subjects on different days, exploring verbal working memory, spatial working memory, and fluid intelligence. Sustained attention performance was also evaluated in a task interleaved between resting state scans. Functional connectivity within and between the DMN and TPN was related to performance on these tasks. Decreased TPN resting state connectivity was found to significantly correlate with fewer errors on an interrupter task presented during a spatial working memory paradigm and decreased DMN/TPN anti-correlation was significantly correlated with fewer errors on an interrupter task presented during a verbal working memory paradigm. A trend for increased DMN resting state connectivity to correlate to measures of fluid intelligence was also observed. These results provide additional evidence of the relationship between resting state networks and behavioral performance, and show that such results can be observed with high temporal resolution fMRI. Because cognitive scores and functional connectivity were collected on nonconsecutive days, these results highlight the stability of functional connectivity/cognitive performance coupling.
A Demands-Resources Model of Work Pressure in IT Student Task Groups
ERIC Educational Resources Information Center
Wilson, E. Vance; Sheetz, Steven D.
2010-01-01
This paper presents an initial test of the group task demands-resources (GTD-R) model of group task performance among IT students. We theorize that demands and resources in group work influence formation of perceived group work pressure (GWP) and that heightened levels of GWP inhibit group task performance. A prior study identified 11 factors…
ERIC Educational Resources Information Center
Wiley, Jennifer; Jarosz, Andrew F.; Cushen, Patrick J.; Colflesh, Gregory J. H.
2011-01-01
The correlation between individual differences in working memory capacity and performance on the Raven's Advanced Progressive Matrices (RAPM) is well documented yet poorly understood. The present work proposes a new explanation: that the need to use a new combination of rules on RAPM problems drives the relation between performance and working…
Ohlenforst, Barbara; Souza, Pamela E; MacDonald, Ewen N
2016-01-01
Previous work has shown that individuals with lower working memory demonstrate reduced intelligibility for speech processed with fast-acting compression amplification. This relationship has been noted in fluctuating noise, but the extent of noise modulation that must be present to elicit such an effect is unknown. This study expanded on previous study by exploring the effect of background noise modulations in relation to compression speed and working memory ability, using a range of signal to noise ratios. Twenty-six older participants between ages 61 and 90 years were grouped by high or low working memory according to their performance on a reading span test. Speech intelligibility was measured for low-context sentences presented in background noise, where the noise varied in the extent of amplitude modulation. Simulated fast- or slow-acting compression amplification combined with individual frequency-gain shaping was applied to compensate for the individual's hearing loss. Better speech intelligibility scores were observed for participants with high working memory when fast compression was applied than when slow compression was applied. The low working memory group behaved in the opposite way and performed better under slow compression compared with fast compression. There was also a significant effect of the extent of amplitude modulation in the background noise, such that the magnitude of the score difference (fast versus slow compression) depended on the number of talkers in the background noise. The presented signal to noise ratios were not a significant factor on the measured intelligibility performance. In agreement with earlier research, high working memory allowed better speech intelligibility when fast compression was applied in modulated background noise. In the present experiment, that effect was present regardless of the extent of background noise modulation.
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.
The effects of working memory on brain-computer interface performance.
Sprague, Samantha A; McBee, Matthew T; Sellers, Eric W
2016-02-01
The purpose of the present study is to evaluate the relationship between working memory and BCI performance. Participants took part in two separate sessions. The first session consisted of three computerized tasks. The List Sorting Working Memory Task was used to measure working memory, the Picture Vocabulary Test was used to measure general intelligence, and the Dimensional Change Card Sort Test was used to measure executive function, specifically cognitive flexibility. The second session consisted of a P300-based BCI copy-spelling task. The results indicate that both working memory and general intelligence are significant predictors of BCI performance. This suggests that working memory training could be used to improve performance on a BCI task. Working memory training may help to reduce a portion of the individual differences that exist in BCI performance allowing for a wider range of users to successfully operate the BCI system as well as increase the BCI performance of current users. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Steady and unsteady three-dimensional transonic flow computations by integral equation method
NASA Technical Reports Server (NTRS)
Hu, Hong
1994-01-01
This is the final technical report of the research performed under the grant: NAG1-1170, from the National Aeronautics and Space Administration. The report consists of three parts. The first part presents the work on unsteady flows around a zero-thickness wing. The second part presents the work on steady flows around non-zero thickness wings. The third part presents the massively parallel processing implementation and performance analysis of integral equation computations. At the end of the report, publications resulting from this grant are listed and attached.
ERIC Educational Resources Information Center
Marschall, Daniel, Ed.
A consensus that unions must develop coherent and comprehensive policies on new work systems and continuous learning in order to guide local activities, was the central theme of this conference on the interrelated issues of the high performance work organization. These proceedings include the following presentations: "Labor's Stake in High…
ERIC Educational Resources Information Center
Blickle, Gerhard; Frohlich, Julia K.; Ehlert, Sandra; Pirner, Katharina; Dietl, Erik; Hanes, T. Johnston; Ferris, Gerald R.
2011-01-01
Socioanalytic theory postulates that job performance ratings are predicted by basic social motives moderated by social competency. The two motives are the motive to get along with others and the motive to achieve status and power. The present two-study investigation assessed these motives as work values and collected supervisors' job performance…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kruger, Albert A.; Piepel, Gregory F.; Landmesser, S. M.
2013-11-13
This report is the last in a series of currently scheduled reports that presents the results from the High Level Waste (HLW) glass formulation development and testing work performed at the Vitreous State Laboratory (VSL) of the Catholic University of America (CUA) and the development of IHLW property-composition models performed jointly by Pacific Northwest National Laboratory (PNNL) and VSL for the River Protection Project-Waste Treatment and Immobilization Plant (RPP-WTP). Specifically, this report presents results of glass testing at VSL and model development at PNNL for Product Consistency Test (PCT), one-percent crystal fraction temperature (T1%), electrical conductivity (EC), and viscosity ofmore » HLW glasses. The models presented in this report may be augmented and additional validation work performed during any future immobilized HLW (IHLW) model development work. Completion of the test objectives is addressed.« less
Visuospatial working memory in very preterm and term born children--impact of age and performance.
Mürner-Lavanchy, I; Ritter, B C; Spencer-Smith, M M; Perrig, W J; Schroth, G; Steinlin, M; Everts, R
2014-07-01
Working memory is crucial for meeting the challenges of daily life and performing academic tasks, such as reading or arithmetic. Very preterm born children are at risk of low working memory capacity. The aim of this study was to examine the visuospatial working memory network of school-aged preterm children and to determine the effect of age and performance on the neural working memory network. Working memory was assessed in 41 very preterm born children and 36 term born controls (aged 7-12 years) using functional magnetic resonance imaging (fMRI) and neuropsychological assessment. While preterm children and controls showed equal working memory performance, preterm children showed less involvement of the right middle frontal gyrus, but higher fMRI activation in superior frontal regions than controls. The younger and low-performing preterm children presented an atypical working memory network whereas the older high-performing preterm children recruited a working memory network similar to the controls. Results suggest that younger and low-performing preterm children show signs of less neural efficiency in frontal brain areas. With increasing age and performance, compensational mechanisms seem to occur, so that in preterm children, the typical visuospatial working memory network is established by the age of 12 years. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Jatobá, Alessandro; de Carvalho, Paulo Victor R; da Cunha, Amauri Marques
2012-01-01
Work in organizations requires a minimum level of consensus on the understanding of the practices performed. To adopt technological devices to support the activities in environments where work is complex, characterized by the interdependence among a large number of variables, understanding about how work is done not only takes an even greater importance, but also becomes a more difficult task. Therefore, this study aims to present a method for modeling of work in complex systems, which allows improving the knowledge about the way activities are performed where these activities do not simply happen by performing procedures. Uniting techniques of Cognitive Task Analysis with the concept of Work Process, this work seeks to provide a method capable of providing a detailed and accurate vision of how people perform their tasks, in order to apply information systems for supporting work in organizations.
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?)…
Job characteristics, flow, and performance: the moderating role of conscientiousness.
Demerouti, Evangelia
2006-07-01
The present article aims to show the importance of positive work-related experiences within occupational health psychology by examining the relationship between flow at work (i.e., absorption, work enjoyment, and intrinsic work motivation) and job performance. On the basis of the literature, it was hypothesized that (a) motivating job characteristics are positively related to flow at work and (b) conscientiousness moderates the relationship between flow and other ratings of (in-role and out-of-role) performance. The hypotheses were tested on a sample of 113 employees from several occupations. Results of moderated structural equation modeling analyses generally supported the hypotheses. Motivating job characteristics were predictive of flow, and flow predicted in-role and extra-role performance, for only conscientious employees.
Influence of Manual Labor at Work on Muscular Fitness and Its Relationship With Work Performance.
Ryan, Eric D; Thompson, Brennan J; Sobolewski, Eric J
2016-10-01
The present study examined the influence of workplace manual labor on measures of muscular fitness, with a secondary aim to investigate the relationship between muscular fitness and work performance in blue-collar (BC) workers. Leg extension isokinetic strength at slow and fast velocities, hamstring and hip-flexor flexibility, and low back muscular endurance were examined in young and older BC workers and white-collar (WC) controls, while work performance was examined in the BC cohort. There were no differences in muscular fitness variables between BC and WC groups; however, the older men had lower low back muscular endurance (-43.0%) and strength at slow (-9.4%) and fast (-12.7%) velocities. Work performance was associated with strength at fast velocities (r = 0.633) in the older BC workers. Leg strength may influence work performance, with higher velocities becoming more important in older workers.
Alderson, R Matt; Kasper, Lisa J; Patros, Connor H G; Hudec, Kristen L; Tarle, Stephanie J; Lea, Sarah E
2015-01-01
The episodic buffer component of working memory was examined in children with attention deficit/hyperactivity disorder (ADHD) and typically developing peers (TD). Thirty-two children (ADHD = 16, TD = 16) completed three versions of a phonological working memory task that varied with regard to stimulus presentation modality (auditory, visual, or dual auditory and visual), as well as a visuospatial task. Children with ADHD experienced the largest magnitude working memory deficits when phonological stimuli were presented via a unimodal, auditory format. Their performance improved during visual and dual modality conditions but remained significantly below the performance of children in the TD group. In contrast, the TD group did not exhibit performance differences between the auditory- and visual-phonological conditions but recalled significantly more stimuli during the dual-phonological condition. Furthermore, relative to TD children, children with ADHD recalled disproportionately fewer phonological stimuli as set sizes increased, regardless of presentation modality. Finally, an examination of working memory components indicated that the largest magnitude between-group difference was associated with the central executive. Collectively, these findings suggest that ADHD-related working memory deficits reflect a combination of impaired central executive and phonological storage/rehearsal processes, as well as an impaired ability to benefit from bound multimodal information processed by the episodic buffer.
Electrodynamic Tether Operations and Control
NASA Technical Reports Server (NTRS)
Glaese, John R.
2001-01-01
This Final Report is organized by tasks from the statement of work (SOW). A brief statement of each task with its task description followed by a discussion of the work performed is presented. The period of performance for this contract phase was from July 21, 2000 to March 19, 2001.
Introduction of the UNIX International Performance Management Work Group
NASA Technical Reports Server (NTRS)
Newman, Henry
1993-01-01
In this paper we presented the planned direction of the UNIX International Performance Management Work Group. This group consists of concerned system developers and users who have organized to synthesize recommendations for standard UNIX performance management subsystem interfaces and architectures. The purpose of these recommendations is to provide a core set of performance management functions and these functions can be used to build tools by hardware system developers, vertical application software developers, and performance application software developers.
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
Physicians' professional performance: an occupational health psychology perspective.
Scheepers, Renée A
2017-12-01
Physician work engagement is considered to benefit physicians' professional performance in clinical teaching practice. Following an occupational health psychology perspective, this PhD report presents research on how physicians' professional performance in both doctor and teacher roles can be facilitated by work engagement and how work engagement is facilitated by job resources and personality traits. First, we conducted a systematic review on the impact of physician work engagement and related constructs (e. g. job satisfaction) on physicians' performance in patient care. We additionally investigated physician work engagement and job resources in relation to patient care experience with physicians' performance at ten outpatient clinics covering two hospitals. In a following multicentre survey involving 61 residency training programs of 18 hospitals, we studied associations between physician work engagement and personality traits with resident evaluations of physicians' teaching performance. The findings showed that physician work engagement was associated with fewer reported medical errors and that job satisfaction was associated with better communication and patient satisfaction. Autonomy and learning opportunities were positively associated with physician work engagement. Work engagement was positively associated with teaching performance. In addition, physician work engagement was most likely supported by personality trait conscientiousness (e. g. responsibility). Given the reported associations of physician work engagement with aspects of their professional performance, hospitals could support physician work engagement in service of optimal performance in residency training and patient care. This could be facilitated by worker health surveillance, peer support or promoting job crafting at the individual or team level.
47 CFR 1.1420 - Timeline for access to utility poles.
Code of Federal Regulations, 2011 CFR
2011-10-01
... estimate of charges to perform all necessary make-ready work within 14 days of providing the response... estimate of charges to perform make-ready work beginning 14 days after the estimate is presented. (2) A...-ready procedure. (2) For wireless attachments above the communications space, the notice shall: (i...
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.
Spatial-sequential and spatial-simultaneous working memory in individuals with Williams syndrome.
Lanfranchi, Silvia; De Mori, Letizia; Mammarella, Irene C; Carretti, Barbara; Vianello, Renzo
2015-05-01
The aim of the present study was to compare visuospatial working memory performance in 18 individuals with Williams syndrome (WS) and 18 typically developing (TD) children matched for nonverbal mental age. Two aspects were considered: task presentation format (i.e., spatial-sequential or spatial-simultaneous), and level of attentional control (i.e., passive or active tasks). Our results showed that individuals with WS performed less well than TD children in passive spatial-simultaneous tasks, but not in passive spatial-sequential tasks. The former's performance was also worse in both active tasks. These findings suggest an impairment in the spatial-simultaneous working memory of individuals with WS, together with a more generalized difficulty in tasks requiring information storage and concurrent processing, as seen in other etiologies of intellectual disability.
Kubota, Kazumi; Shimazu, Akihito; Kawakami, Norito; Takahashi, Masaya; Nakata, Akinori; Schaufeli, Wilmar B
2011-01-01
The aim of the present study is to demonstrate the distinctiveness of work engagement and workaholism by examining their relationships with sleep quality and job performance. A total of 447 nurses from 3 hospitals in Japan were surveyed using a self-administrated questionnaire including Utrecht Work Engagement Scale (UWES), the Dutch Workaholism Scale (DUWAS), questions on sleep quality (7 items) regarding (1) difficulty initiating sleep, (2) difficulty maintaining sleep, (3) early morning awakening, (4) dozing off or napping in daytime, (5) excessive daytime sleepiness at work, (6) difficulty awakening in the morning, and (7) tiredness awakening in the morning, and the World Health Organization Health Work Performance Questionnaire. The Structural Equation Modeling showed that, work engagement was positively related to sleep quality and job performance whereas workaholism negatively to sleep quality and job performance. The findings suggest that work engagement and workaholism are conceptually distinctive and that the former is positively and the latter is negatively related to well-being (i.e., good sleep quality and job performance).
Phonological awareness and writing skills in children with Down syndrome.
Lavra-Pinto, Bárbara de; Lamprecht, Regina Ritter
2010-01-01
Down syndrome, phonological awareness, writing and working memory. to evaluate the phonological awareness of Brazilian children with Down syndrome; to analyze the relationship between the writing hypothesis and the phonological awareness scores of the participants; to compare the performance of children with Down syndrome to that of children with typical development according to the Phonological Awareness: Tool for sequential evaluation (PHONATSE), using the writing hypothesis as a matching criteria; to verify the correlation between the phonological awareness measurements and the phonological working memory. a group of eleven children aged between 7 and 14 years (average: 9 y 10 m) was selected for the study. Phonological awareness was evaluated using the PHONATSE. The phonological working memory was evaluated through an instrument developed by the researcher. all subjects presented measurable levels of phonological awareness through the PHONATSE. The phonological awareness scores and the writing hypothesis presented a significant positive association. The performance of children with Down syndrome was significantly lower than children with typical development who presented the same writing hypothesis. Measurements of phonological awareness and phonological working memory presented significant positive correlations. the phonological awareness of Brazilian children with Down syndrome can be evaluated through the PHONATSE. Syllable awareness improves with literacy, whereas phonemic awareness seems to result from written language learning. The phonological working memory influences the performance of children with Down syndrome in phonological awareness tasks.
Innstrand, Siw Tone; Langballe, Ellen Melbye; Espnes, Geir Arild; Aasland, Olaf Gjerløw; Falkum, Erik
2010-12-01
The aim of the present study was to examine the longitudinal relationship between job performance-based self-esteem (JPB-SE) and work-home interaction (WHI) in terms of the direction of the interaction (work-to-home vs. home-to-work) and the effect (conflict vs. facilitation). A sample of 3,475 respondents from eight different occupational groups (lawyers, physicians, nurses, teachers, church ministers, bus drivers, and people working in advertising and information technology) supplied data at two points of time with a two-year time interval. The two-wave, cross-lagged structural equations modeling (SEM) analysis demonstrated reciprocal relationships between these variables, i.e., job performance-based self-esteem may act as a precursor as well as an outcome of work-home interaction. The strongest association was between job performance-based self-esteem and work-to-home conflict. Previous research on work-home interaction has mainly focused on situational factors. This longitudinal study expands the work-home literature by demonstrating how individual vulnerability (job performance-based self-esteem) contributes to the explanation of work-home interactions. © 2010 The Authors. Scandinavian Journal of Psychology © 2010 The Scandinavian Psychological Associations.
DOT National Transportation Integrated Search
2013-11-01
This report presents research performed analyzing crashes in work zones in the state of New Jersey so as to : identify critical areas in work zones susceptible to crashes and key factors that contribute to these crashes. A field : data collection on ...
Owens, Matthew; Stevenson, Jim; Norgate, Roger; Hadwin, Julie A
2008-10-01
Working memory skills are positively associated with academic performance. In contrast, high levels of trait anxiety are linked with educational underachievement. Based on Eysenck and Calvo's (1992) processing efficiency theory (PET), the present study investigated whether associations between anxiety and educational achievement were mediated via poor working memory performance. Fifty children aged 11-12 years completed verbal (backwards digit span; tapping the phonological store/central executive) and spatial (Corsi blocks; tapping the visuospatial sketchpad/central executive) working memory tasks. Trait anxiety was measured using the State-Trait Anxiety Inventory for Children. Academic performance was assessed using school administered tests of reasoning (Cognitive Abilities Test) and attainment (Standard Assessment Tests). The results showed that the association between trait anxiety and academic performance was significantly mediated by verbal working memory for three of the six academic performance measures (math, quantitative and non-verbal reasoning). Spatial working memory did not significantly mediate the relationship between trait anxiety and academic performance. On average verbal working memory accounted for 51% of the association between trait anxiety and academic performance, while spatial working memory only accounted for 9%. The findings indicate that PET is a useful framework to assess the impact of children's anxiety on educational achievement.
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.
Ha, Jong Goon; Man Kim, Ji; Hwang, Won Ju; Lee, Sang Gyu
2014-09-01
The aim of the present study was to analyse the impact of organisational characteristics on the turnover intention of care workers working at nursing homes in Korea. Study participants included 504 care workers working at 14 nursing homes in Korea. The variables measured were: high-performance work practices, consisting of five subfactors (official training, employment stability, autonomy, employee participation and group-based payment); organisational commitment, consisting of three subfactors (affective, normative and continuance commitment); organisational support; and turnover intention. The inter-relationship between high-performance work practices, organisational support, organisational commitment and turnover intention and the fit of the hypothetical model were analysed using structural equation modelling. According to our analysis, high-performance work practices not only had a direct effect on turnover intention, but also an indirect effect by mediating organisational support and commitment. The factor having the largest direct influence on turnover intention was organisational commitment. The results of the present study suggest that to improve health conditions for frail elderly patients at nursing homes, as well as the efficiency of nursing homes through the continuance of nursing service and enhancement of quality of service, long-term care facilities should reduce the turnover intention of care workers by increasing their organisational commitment by actively implementing high-performance work practices.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sprik, Samuel; Kurtz, Jennifer M; Ainscough, Christopher D
In this presentation, the National Renewable Energy Laboratory presented aggregated analysis results on the performance of existing hydrogen stations, including performance, operation, utilization, maintenance, safety, hydrogen quality, and cost. The U.S. Department of Energy funds technology validation work at NREL through its National Fuel Cell Technology Evaluation Center (NFCTEC).
ERIC Educational Resources Information Center
Hunt, Earl; Hertzog, Christopher
In order to alleviate present and anticipated personnel shortages, the Armed Services will have to move away from the present reliance on young adults as a source of personnel. Questions remain about the effects of age changes in cognition on work performance of older personnel. Changes in cognitive capacities over the adult working years are…
2012-01-01
ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ...ability to perform .84 This chapter presents an overview of topics surrounding hydration, dehydration, and rehydration. The terms euhydration, hypohydration...environments, or illness, inability to maintain fluid balance can seriously jeopardize health and the ability to perform .84 This chapter presents an overview
Enhanced emotional interference on working memory performance in adults with ADHD.
Marx, Ivo; Domes, Gregor; Havenstein, Carolin; Berger, Christoph; Schulze, Lars; Herpertz, Sabine C
2011-09-01
Subjects with attention-deficit/hyperactivity disorder (ADHD) suffer from both executive dysfunction and deficits in emotion regulation. However, up to now, there has been no research demonstrating a clear impact of emotional dysregulation on cognitive performance in subjects with ADHD. Male and female adults with ADHD (n=39) and gender- and IQ-matched control subjects (n=40) performed an emotional working memory task (n-back task). In the background of the task, we presented neutral and negative stimuli varied in emotional saliency (negative pictures with low saliency, negative pictures with high saliency), but subjects were instructed to ignore these pictures and to process the working memory task as quickly and as accurately as possible. Compared to control subjects, ADHD patients showed both a general working memory deficit and enhanced distractability by emotionally salient stimuli in terms of lower n-back performance accuracy. In particular, while controls showed impaired WM performance when presented with highly arousing negative background pictures, a comparable decrement was observed in the ADHD group already with lowly arousing pictures. Our results suggest that difficulties in suppressing attention towards emotionally laden stimuli might result from deficient executive control in ADHD.
A Peer-Reviewed Research Assignment for Large Classes.
ERIC Educational Resources Information Center
Henderson, LaRhee; Buising, Charisse
2000-01-01
Introduces a writing exercise students work on in collaborative groups. Aims to enhance students' scientific research paper writing skills and provide experience working in collaborative groups. Presents evaluation criteria for peer-group evaluation of a poster presentation, intra-group evaluation of peer performance, and peer-group evaluation of…
ERIC Educational Resources Information Center
Pesonen, Inari
2008-01-01
This paper examines two improvisational processes, Authentic Movement (AM) and automatic drawing (AD), the possibility of their presentation to the viewer and the meanings such presentation may bring to the work presented. Improvisation has traditionally been used in the process of creating a finished work of art rather than in the finished art…
Strategic Culture Change: The Door to Achieving High Performance and Inclusion.
ERIC Educational Resources Information Center
Miller, Frederick A.
1998-01-01
Presents diversity as a resource to create a high performing work culture that enables all employees to do their best work. Distinguishes between diversity and inclusion, describes a model for diagnosing an organization's culture, sets forth steps for implementing a organizational change, and discusses the human resource professional's role.…
ERIC Educational Resources Information Center
Ram-Tsur, Ronit; Faust, Miriam; Zivotofsky, Ari Z.
2008-01-01
The present study investigates the performance of persons with reading disabilities (PRD) on a variety of sequential visual-comparison tasks that have different working-memory requirements. In addition, mediating relationships between the sequential comparison process and attention and memory skills were looked for. Our findings suggest that PRD…
New technology in turbine aerodynamics
NASA Technical Reports Server (NTRS)
Glassman, A. J.; Moffitt, T. P.
1972-01-01
A cursory review is presented of some of the recent work that has been done in turbine aerodynamic research at NASA-Lewis Research Center. Topics discussed include the aerodynamic effect of turbine coolant, high work-factor (ratio of stage work to square of blade speed) turbines, and computer methods for turbine design and performance prediction. An extensive bibliography is included. Experimental cooled-turbine aerodynamics programs using two-dimensional cascades, full annular cascades, and cold rotating turbine stage tests are discussed with some typical results presented. Analytically predicted results for cooled blade performance are compared to experimental results. The problems and some of the current programs associated with the use of very high work factors for fan-drive turbines of high-bypass-ratio engines are discussed. Turbines currently being investigated make use of advanced blading concepts designed to maintain high efficiency under conditions of high aerodynamic loading. Computer programs have been developed for turbine design-point performance, off-design performance, supersonic blade profile design, and the calculation of channel velocities for subsonic and transonic flow fields. The use of these programs for the design and analysis of axial and radial turbines is discussed.
Organizational citizenship behavior and the quantity and quality of work group performance.
Podsakoff, P M; Ahearne, M; MacKenzie, S B
1997-04-01
Despite the widespread interest in the topic of organizational citizenship behaviors (OCBs), little empirical research has tested the fundamental assumption that these forms of behavior improve the effectiveness of work groups or organizations in which they are exhibited. In the present study, the effects of OCBs on the quantity and quality of the performance of 218 people working in 40 machine crews in a paper mill located in the Northeastern United States were examined. The results indicate that helping behavior and sportsmanship had significant effects on performance quantity and that helping behavior had a significant impact on performance quality. However, civic virtue had no effect on either performance measure.
The effects of autobiographical memory and visual perspective on working memory.
Cheng, Zenghu; She, Yugui
2018-08-01
The present research aims to explore whether recalling and writing about autobiographical memory from different perspectives (first-person perspective vs. third-person perspective) could affect cognitive function. The participants first performed a working memory task to evaluate their working memory capacity as a baseline and then were instructed to recall (Study 1) or write about (Study 2) personal events (failures vs. successes) from the first-person perspective or the third-person perspective. Finally, they performed the working memory task again. The results suggested that autobiographical memory and perspective influence working memory interactively. When recalling a success, the participants who recalled from the third-person perspective performed better than those who recalled from the first-person perspective on the working memory capacity task; when recalling a failure, the opposite was true.
Work stressors, Chinese coping strategies, and job performance in Greater China.
Lu, Luo; Kao, Shu-Fang; Siu, Oi-Ling; Lu, Chang-Qin
2010-08-01
The aim of this research was to jointly test effects of work stressors and coping strategies on job performance among employees in the Greater China region. A self-administered survey was conducted to collect data from three major cities in the region, namely Beijing, Hong Kong, and Taipei (N = 380). Four important work stressors were assessed: heavy workload, organizational constraints, lack of work autonomy, and interpersonal conflict. We used a four-factor model of Chinese coping strategies composed of hobbies/relaxation, active action, seeking social support, and passive adaptation. Job performance was indicated by both task performance (quantity of work, quality of work, job knowledge) and contextual performance (attendance, getting along with others). We found that: (1) work stressors were related to job performance. Specifically, workload had a positive relation with quantity of work, whereas organizational constraints had negative relations with quantity of work and attendance. In addition, interpersonal conflict had a negative relation with getting along with others. (2) Chinese positive coping strategies were positively related to job performance. Specifically, seeking social support had positive relations with quantity of work and getting along with others, whereas active action had positive relations with attendance and job knowledge. (3) Chinese passive adaptation coping behaviors were negatively related to job performance. Specifically, passive adaptation had negative relations with quantity of work, quality of work, and getting along with others. The present study thus found joint effects of work stressors and coping behaviors among Chinese employees in the Greater China region, encompassing three sub-societies of mainland China, Hong Kong, and Taiwan. Differential effects of Chinese positive and passive coping strategies were also noted. Most importantly, all these effects were demonstrated on multiple indicators of job performance, a rarely studied but important strain variable from the organizational point of view.
ERIC Educational Resources Information Center
Nuttman-Shwartz, Orit
2007-01-01
The present study examined the way retirees perceive retirement and continue to work post-retirement. Using a longitudinal design, qualitative and quantitative analyses were performed to examine the effect of preoccupation with work on adjustment to retirement. The findings indicate a wide range of attitudes toward cessation of the working life on…
UV Raman and Fluorescence for Multi-Species Measurement in Hydrocarbon-Fueled High-Speed Propulsion
NASA Technical Reports Server (NTRS)
Skaggs, Patricia Annette; Nandula, Sastri P.; Pitz, Robert W.
1999-01-01
This report documents work performed through the NASA Graduate Student Researchers Program, Grant No. NGT3-52316. Research performed included investigation of two-line fluorescence imaging of OH for temperature measurement and an investigation of negative flame speeds for modeling of premixed turbulent flames. The laboratory work and initial analysis of the fluorescence imaging was performed at NASA Glen Research Center with follow up analysis at Vanderbilt University. The negative flame speed investigation was performed using an opposed jet flow simulation program at Vanderbilt University. The fluorescence imaging work is presented first followed by the negative flame speed investigation.
NASA Technical Reports Server (NTRS)
Stochl, R. J.
1979-01-01
The results of an analysis to estimate the performance that could be obtained by using a chemically reacting gas (nitrogen tetroxide) as the working fluid in a closed Brayton cycle are presented. Compared with data for helium as the working fluid, these results indicate efficiency improvements from 4 to 90 percent, depending on turbine inlet temperature, pressures, and gas residence time in heat transfer equipment.
Bifocal Stereo for Multipath Person Re-Identification
NASA Astrophysics Data System (ADS)
Blott, G.; Heipke, C.
2017-11-01
This work presents an approach for the task of person re-identification by exploiting bifocal stereo cameras. Present monocular person re-identification approaches show a decreasing working distance, when increasing the image resolution to obtain a higher reidentification performance. We propose a novel 3D multipath bifocal approach, containing a rectilinear lens with larger focal length for long range distances and a fish eye lens of a smaller focal length for the near range. The person re-identification performance is at least on par with 2D re-identification approaches but the working distance of the approach is increased and on average 10% more re-identification performance can be achieved in the overlapping field of view compared to a single camera. In addition, the 3D information is exploited from the overlapping field of view to solve potential 2D ambiguities.
Schedule-Aware Workflow Management Systems
NASA Astrophysics Data System (ADS)
Mans, Ronny S.; Russell, Nick C.; van der Aalst, Wil M. P.; Moleman, Arnold J.; Bakker, Piet J. M.
Contemporary workflow management systems offer work-items to users through specific work-lists. Users select the work-items they will perform without having a specific schedule in mind. However, in many environments work needs to be scheduled and performed at particular times. For example, in hospitals many work-items are linked to appointments, e.g., a doctor cannot perform surgery without reserving an operating theater and making sure that the patient is present. One of the problems when applying workflow technology in such domains is the lack of calendar-based scheduling support. In this paper, we present an approach that supports the seamless integration of unscheduled (flow) and scheduled (schedule) tasks. Using CPN Tools we have developed a specification and simulation model for schedule-aware workflow management systems. Based on this a system has been realized that uses YAWL, Microsoft Exchange Server 2007, Outlook, and a dedicated scheduling service. The approach is illustrated using a real-life case study at the AMC hospital in the Netherlands. In addition, we elaborate on the experiences obtained when developing and implementing a system of this scale using formal techniques.
Work domain constraints for modelling surgical performance.
Morineau, Thierry; Riffaud, Laurent; Morandi, Xavier; Villain, Jonathan; Jannin, Pierre
2015-10-01
Three main approaches can be identified for modelling surgical performance: a competency-based approach, a task-based approach, both largely explored in the literature, and a less known work domain-based approach. The work domain-based approach first describes the work domain properties that constrain the agent's actions and shape the performance. This paper presents a work domain-based approach for modelling performance during cervical spine surgery, based on the idea that anatomical structures delineate the surgical performance. This model was evaluated through an analysis of junior and senior surgeons' actions. Twenty-four cervical spine surgeries performed by two junior and two senior surgeons were recorded in real time by an expert surgeon. According to a work domain-based model describing an optimal progression through anatomical structures, the degree of adjustment of each surgical procedure to a statistical polynomial function was assessed. Each surgical procedure showed a significant suitability with the model and regression coefficient values around 0.9. However, the surgeries performed by senior surgeons fitted this model significantly better than those performed by junior surgeons. Analysis of the relative frequencies of actions on anatomical structures showed that some specific anatomical structures discriminate senior from junior performances. The work domain-based modelling approach can provide an overall statistical indicator of surgical performance, but in particular, it can highlight specific points of interest among anatomical structures that the surgeons dwelled on according to their level of expertise.
Spatial working memory load affects counting but not subitizing in enumeration.
Shimomura, Tomonari; Kumada, Takatsune
2011-08-01
The present study investigated whether subitizing reflects capacity limitations associated with two types of working memory tasks. Under a dual-task situation, participants performed an enumeration task in conjunction with either a spatial (Experiment 1) or a nonspatial visual (Experiment 2) working memory task. Experiment 1 showed that spatial working memory load affected the slope of a counting function but did not affect subitizing performance or subitizing range. Experiment 2 showed that nonspatial visual working memory load affected neither enumeration efficiency nor subitizing range. Furthermore, in both spatial and nonspatial memory tasks, neither subitizing efficiency nor subitizing range was affected by amount of imposed memory load. In all the experiments, working memory load failed to influence slope, subitizing range, or overall reaction time. These findings suggest that subitizing is performed without either spatial or nonspatial working memory. A possible mechanism of subitizing with independent capacity of working memory is discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, W Michael; Kohlmeyer, Axel; Plimpton, Steven J
The use of accelerators such as graphics processing units (GPUs) has become popular in scientific computing applications due to their low cost, impressive floating-point capabilities, high memory bandwidth, and low electrical power requirements. Hybrid high-performance computers, machines with nodes containing more than one type of floating-point processor (e.g. CPU and GPU), are now becoming more prevalent due to these advantages. In this paper, we present a continuation of previous work implementing algorithms for using accelerators into the LAMMPS molecular dynamics software for distributed memory parallel hybrid machines. In our previous work, we focused on acceleration for short-range models with anmore » approach intended to harness the processing power of both the accelerator and (multi-core) CPUs. To augment the existing implementations, we present an efficient implementation of long-range electrostatic force calculation for molecular dynamics. Specifically, we present an implementation of the particle-particle particle-mesh method based on the work by Harvey and De Fabritiis. We present benchmark results on the Keeneland InfiniBand GPU cluster. We provide a performance comparison of the same kernels compiled with both CUDA and OpenCL. We discuss limitations to parallel efficiency and future directions for improving performance on hybrid or heterogeneous computers.« less
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.
Suvinen, T I; Ahlberg, J; Rantala, M; Nissinen, M; Lindholm, H; Könönen, M; Savolainen, A
2004-08-01
The aim of the present study was to assess the associations between different types of perceived stress, pain and work performance among non-patients with clinical signs of muscle pain in the head/neck region. One-fifth (n = 241) of the 1339 media employees who had participated in a previous survey (Ahlberg J. et al., J Psychosom Res 2002; 53: 1077-1081) were randomly selected for standardized clinical examinations. Altogether 49% (n = 118) of these subjects had clinical signs of temporomandibular and/or neck muscle pain and were enrolled in the present study. The mean age of the study sample was 46.9 years (s.d. 6.6) and the female to male distribution 2:1. Of the 118 employees 46.5% reported that the pain problem interfered with their ability to work. Perceived ability to work was not significantly associated with age, gender or work positions. According to logistic regression, reduced work performance was significantly positively associated with continuous pain [odds ratio (OR) 4.38; 95% CI 1.21-15.7], level of perceived pain severity (OR 1.30; 95% CI 1.04-1.63), and health stress (OR 2.08; 95% CI 1.22-3.54). The results of this study indicated an association between specific self-reported stress regarding health and work issues, pain and work performance. From a preventive perspective this indicates a need for increased awareness about these associations on not only individual level but also at the organizational level and in health care. Copyright 2004 Blackwell Publishing Ltd.
The Paper Beam: Hands-On Design for Team Work Experience of Freshman in Engineering
ERIC Educational Resources Information Center
Kalkani, Efrossini C.; Boussiakou, Iris K.; Boussiakou, Leda G.
2005-01-01
The present research refers to the assigning of a hands-on group project to freshman engineering students, evaluating their performance, and deriving conclusions on student benefits and educational advances. The research procedure included action plans for the instructor and the students, instructions to the students on performing the work,…
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…
Visual Information Can Hinder Working Memory Processing of Speech
ERIC Educational Resources Information Center
Mishra, Sushmit; Lunner, Thomas; Stenfelt, Stefan; Ronnberg, Jerker; Rudner, Mary
2013-01-01
Purpose: 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. Method: In Experiment 1, 20 young adults with normal hearing performed the CSCT and an independent battery of…
Low Speed Rot or/Fuselage Interactional Aerodynamics
NASA Technical Reports Server (NTRS)
Barnwell, Richard W.; Prichard, Devon S.
2003-01-01
This report presents work performed under a Cooperative Research Agreement between Virginia Tech and the NASA Langley Research Center. The work involved development of computational techniques for modeling helicopter rotor/airframe aerodynamic interaction. A brief overview of the problem is presented, the modeling techniques are described, and selected example calculations are briefly discussed.
Spatial-Sequential and Spatial-Simultaneous Working Memory in Individuals with Williams Syndrome
ERIC Educational Resources Information Center
Lanfranchi, Silvia; De Mori, Letizia; Mammarella, Irene C.; Carretti, Barbara; Vianello, Renzo
2015-01-01
The aim of the present study was to compare visuospatial working memory performance in 18 individuals with Williams syndrome (WS) and 18 typically developing (TD) children matched for nonverbal mental age. Two aspects were considered: task presentation format (i.e., spatial-sequential or spatial-simultaneous), and level of attentional control…
Hofmans, Joeri; Debusscher, Jonas; Dóci, Edina; Spanouli, Andromachi; De Fruyt, Filip
2015-01-01
Whereas several studies have demonstrated that core self-evaluations (CSE)-or one's appraisals about one's own self-worth, capabilities, and competences-relate to job outcomes, less is known about the mechanisms underlying these relationships. In the present study, we address this issue by examining the role of within- and between-person variation in CSE in the relationship between work pressure and task performance. We hypothesized that (a) work pressure relates to task performance in a curvilinear way, (b) state CSE mediates the curvilinear relationship between work pressure and task performance, and (c) the relationship between work pressure and state CSE is moderated by trait CSE. Our hypotheses were tested via a 10-day daily diary study with 55 employees in which trait CSE was measured at baseline, while work pressure, task performance, and state CSE were assessed on a daily basis. Bayesian multilevel path analysis showed that work pressure affects task performance via state CSE, with state CSE increasing as long as the employee feels that (s)he is able to handle the work pressure, while it decreases when the level of work pressure exceeds the employees' coping abilities. Moreover, we found that for people low on trait CSE, the depleting effect of work pressure via state CSE happens for low levels of work pressure, while for people high in trait CSE the depleting effect is located at high levels of work pressure. Together, our findings suggest that the impact of work pressure on task performance is driven by a complex interplay of between- and within-person differences in CSE.
AbuAlRub, Raeda Fawzi; Al-Zaru, Ibtisam Moawiah
2008-04-01
To investigate: (1) relationships between job stress, recognition of nurses' performance, job performance and intention to stay among hospital nurses; and (2) the buffering effect of recognition of staff performance on the 'stress-intention to stay at work' relationship. Workplace stress tremendously affects today's workforce. Recognition of nurses' performance needs further investigation to determine if it enhances the level of intention to stay at work and if it can buffer the negative effects of stress on nurses' intention to stay at work. The sample of the present study was a convenience one. It consisted of 206 Jordanian staff nurses who completed a structured questionnaire. The findings of the study indicated a direct and a buffering effect of recognition of nurses' performance on job stress and the level of intention to stay at work. The results of the study indicated the importance of recognition for outstanding performance as well as achievements. Implications for nursing management The results of this study support the need to focus on the implementation of recognition strategies in the workplace to reduce job stress and enhance retention.
Control Chart on Semi Analytical Weighting
NASA Astrophysics Data System (ADS)
Miranda, G. S.; Oliveira, C. C.; Silva, T. B. S. C.; Stellato, T. B.; Monteiro, L. R.; Marques, J. R.; Faustino, M. G.; Soares, S. M. V.; Ulrich, J. C.; Pires, M. A. F.; Cotrim, M. E. B.
2018-03-01
Semi-analytical balance verification intends to assess the balance performance using graphs that illustrate measurement dispersion, trough time, and to demonstrate measurements were performed in a reliable manner. This study presents internal quality control of a semi-analytical balance (GEHAKA BG400) using control charts. From 2013 to 2016, 2 weight standards were monitored before any balance operation. This work intended to evaluate if any significant difference or bias were presented on weighting procedure over time, to check the generated data reliability. This work also exemplifies how control intervals are established.
Designing for Annual Spacelift Performance
NASA Technical Reports Server (NTRS)
McCleskey, Carey M.; Zapata, Edgar
2017-01-01
This paper presents a methodology for approaching space launch system design from a total architectural point of view. This different approach to conceptual design is contrasted with traditional approaches that focus on a single set of metrics for flight system performance, i.e., payload lift per flight, vehicle mass, specific impulse, etc. The approach presented works with a larger set of metrics, including annual system lift, or "spacelift" performance. Spacelift performance is more inclusive of the flight production capability of the total architecture, i.e., the flight and ground systems working together as a whole to produce flights on a repeated basis. In the proposed methodology, spacelift performance becomes an important design-for-support parameter for flight system concepts and truly advanced spaceport architectures of the future. The paper covers examples of existing system spacelift performance as benchmarks, points out specific attributes of space transportation systems that must be greatly improved over these existing designs, and outlines current activity in this area.
Human Factors and Modeling Methods in the Development of Control Room Modernization Concepts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hugo, Jacques V.; Slay III, Lorenzo
nuclear power plants. Although the nuclear industry has made steady improvement in outage optimization, each day of a refueling outage still represents an opportunity to save millions of dollars and each day an outage extends past its planned end date represents millions of dollars that may have been spent unnecessarily. Reducing planned outage duration or preventing outage extensions requires careful management of the outage schedule as well as constant oversight and monitoring of work completion during the outage execution. During a typical outage, there are typically more than 10,000 activities on the schedule that, if not managed efficiently, may causemore » expensive outage delays. Management of outages currently relies largely on paper-based resources and general-purpose office software. A typical tool currently used to monitor work performance is a burn-down curve, where total remaining activities are plotted against the baseline schedule to track bulk work completion progress. While these tools are useful, there is still considerable uncertainty during a typical outage that bulk work progress is adequate and therefore a lot of management time is spent analyzing the situation on a daily basis. This paper describes recent advances made in developing a framework for the design of visual outage information presentation, as well as an overview of the scientific principles that informed the development of the visualizations. To test the utility of advanced visual outage information presentation, an outage management dashboard software application was created as part of the Department of Energy’s Advanced Outage Control Center project. This dashboard is intended to present all the critical information an outage manager would need to understand the current status of a refueling outage. The dashboard presents the critical path, bulk work performance, key performance indicators, outage milestones and metrics relating current performance to historical performance. Additionally, the dashboard includes data analysis tools to allow outage managers to drill down into the underlying data to understand the drivers of the indicators.« less
Embodied labour in music work.
Pettinger, Lynne
2015-06-01
This paper frames the work of performance as embodied labour in order to understand the contingent production of particular music performances. It is an interdisciplinary account that sits at the intersection of the sociology of work, culture and the body. The concept of embodied labour is developed with reference to the complex account of materiality - of bodies and things - present in Tim Ingold's account of skill. This material account of skill is used to inform use to develop already of well established conceptualizations of body labour: craft, emotional and aesthetic labour through a reading of how these dimensions of embodied labour make possible the work of performance. © London School of Economics and Political Science 2015.
Simulator Training Requirements and Effectiveness Study (STRES). Part 1. Abstract Bibliography
1981-01-01
august 1977 tnrougn January 19dU. The work was performed by a team made up of Canyon Research Group, Inc; Seville Research Corporation; and United...Dr. Thomas Eggemeier. A tri-service STRES Advisory Team participated in guiding and monitoring the work performed during this contract to assure its...8217 STRUCTURE OF THE STRES PROGRAM The primary objectives of STRES, as described in the contract Statement of Work for the present efforts, are to define
Impact performance of two bamboo-based laminated composites
Huanrong Liu; Zehui Jiang; Zhengjun Sun; Yan Yan; Zhiyong Cai; Xiubiao Zhang
2017-01-01
The present work aims to determine the impact performance of two bamboo-based laminated composites [bamboo/poplar laminated composite (BPLC) and bamboo/ glass fiber laminated composite (BGFLC)] using lowvelocity impact tests by a drop tower. In addition, fracture characteristics were evaluated using computed tomography (CT). Results showed that BPLC presented better...
Computational Investigation on the performance of thermo-acoustically driven pulse tube refrigerator
NASA Astrophysics Data System (ADS)
Skaria, Mathew; Rasheed, K. K. Abdul; Shafi, K. A.; Kasthurirengan, S.; Behera, Upendra
2017-02-01
A Thermoacoustic Pulse Tube Refrigeration (TAPTR) system employs a thermo acoustic engine as the pressure wave generator instead of mechanical compressor. Such refrigeration systems are highly reliable due to the absence of moving components, structural simplicity and the use of environmental friendly working fluids. In the present work, a traveling wave thermoacoustic primmover (TWTAPM) has been developed and it is coupled to a pulse tube cryocooler. The performance of TAPTR depends on the operating and working fluid parameters. Simulation studies of the system has been performed using ANSYS Fluent and compared with experimental results.
X-ray Variability Constraints on Compton Cloud Models of Cygnus X-1
NASA Technical Reports Server (NTRS)
Vaughan, Brian
1999-01-01
We have now completed this work, and all related publications have either appeared in print or are currently in press. A list of these publications is given below. There have been essentially three works that have arisen from this proposal. Spectral analysis of the data is presented in Dove et al. (1998a). Timing analysis is presented in Nowak et al. (1999a). Theoretical implications of the data analysis are discussed in Nowak et al. (1999b). Preliminary versions of all these works were presented at various conferences, and are reported in Nowak et al. (1997, 1998), Wilms et al. (1997), and Dove et al. (1998b). The grant was predominantly used for salary support for Dr. Michael Nowak, Dr. James Dove, and Dr. J. Wilms during the course of these projects. Grant funds were also used for Dr. Nowak to travel to Caltech to perform data analysis with Dr. Brian Vaughan, and for Dr. Wilms to visit JILA, University of Colorado, where much of this work was performed.
An ambient agent model for analyzing managers' performance during stress
NASA Astrophysics Data System (ADS)
ChePa, Noraziah; Aziz, Azizi Ab; Gratim, Haned
2016-08-01
Stress at work have been reported everywhere. Work related performance during stress is a pattern of reactions that occurs when managers are presented with work demands that are not matched with their knowledge, skills, or abilities, and which challenge their ability to cope. Although there are many prior findings pertaining to explain the development of manager performance during stress, less attention has been given to explain the same concept through computational models. In such, a descriptive nature in psychological theories about managers' performance during stress can be transformed into a causal-mechanistic stage that explains the relationship between a series of observed phenomena. This paper proposed an ambient agent model for analyzing managers' performance during stress. Set of properties and variables are identified through past literatures to construct the model. Differential equations have been used in formalizing the model. Set of equations reflecting relations involved in the proposed model are presented. The proposed model is essential and can be encapsulated within an intelligent agent or robots that can be used to support managers during stress.
Social cognition and work performance of persons with schizophrenia in a Chinese population.
Lo, Panmi; Siu, Andrew M H
2015-01-01
Social-cognitive deficits have a significant impact on the community and vocational functioning of persons with schizophrenia. This study aimed to explore the relationship between social-cognitive abilities and vocational functioning in a Chinese population. We recruited 30 outpatients with schizophrenia to participate. We administered the Chinese Social Cognition and Screening Questionnaire (C-SCSQ) to assess Theory of Mind (ToM), attributional bias, and neurocognition; the Facial Expression Identification Test (FEIT) to assess emotion perception (EP) ability, and the Chinese Work Personality Profile (CWPP) to assess work performance in a simulated work setting. ToM showed a significant negative correlation with attributional bias. The neurocognitive measure displayed a significant positive correlation with ToM and EP. The structural equation model was a good fit to the data (CFI=0.91, RMSEA=0.12), and showed that social-cognitive abilities had a significant impact (-0.41) on work performance. Of the four social-cognitive domains, ToM and paranoid attributional style (PAS) contributed significantly to variations in work performance. These results support the theory that social-cognitive abilities have an impact on work performance. ToM has a positive impact whereas PAS has an adverse effect. Persons with schizophrenia present specific deficits in their social-cognitive abilities, which have significant impact on their work performance and employability.
Patros, Connor H G; Alderson, R Matt; Lea, Sarah E; Tarle, Stephanie J; Kasper, Lisa J; Hudec, Kristen L
2015-03-01
The present study examined the directional relationship between choice-impulsivity and separate indices of phonological and visuospatial working memory performance in boys (aged 8-12 years) with (n=16) and without ADHD (n=19). Results indicated that high ratings of overall ADHD, inattention, and hyperactivity were significantly associated with increased impulsivity and poorer phonological and visuospatial working memory performance. Further, results from bias-corrected bootstrapped mediation analyses revealed a significant indirect effect of visuospatial working memory performance, through choice-impulsivity, on overall ADHD, inattention, and hyperactivity/impulsivity. Collectively, the findings suggest that deficits of visuospatial working memory underlie choice-impulsivity, which in turn contributes to the ADHD phenotype. Moreover, these findings are consistent with a growing body of literature that identifies working memory as a central neurocognitive deficit of ADHD. Copyright © 2015 Elsevier Ltd. All rights reserved.
Ubiquitous Working: Do Work Versus Non-work Environments Affect Decision-Making and Concentration?
Burmeister, Carolin P; Moskaliuk, Johannes; Cress, Ulrike
2018-01-01
New communication technologies and mobile devices have enabled knowledge workers to work independently of location and in more than one fixed environment (ubiquitous working). Previous research shows that physical environments can influence cognition and work performance. We manipulated environment (i.e., a virtual office as a typical work environment compared to a virtual garden as a non-work environment ) and time pressure (i.e., inducing time pressure vs. no time pressure ) in order to investigate whether the environment influences decision-making and concentration. N = 109 students participated in this laboratory experiment. We posited (a) that a work environment would activate a work-related schema which in turn would enhance concentration performance and make decisions more risky compared to non-work environments and (b) that the environmental effect is more pronounced if time pressure is present compared to conditions where no time pressure is present. We found modest hypothesis-confirming main effects of environment on decision-making and concentration but no interaction effect with time pressure. As we used an innovative methodology that entails several limitations, future research is needed to give insights into the process and to investigate whether results hold true for all types of work settings, work demands, or work activities.
Contingent self-esteem, stressors and burnout in working women and men.
Blom, Victoria
2012-01-01
A high work involvement is considered central in the burnout process. Yet, research investigating how high work involvement and psychosocial stressors relate to burnout is scarce. High involvement in terms of performance-based self-esteem (PBSE) refers to individuals' strivings to validate self-worth by achievements, a disposition linked to poor health. The aim of the present study was to examine longitudinally PBSE in relation to burnout while also taking into account work- and private life stressors. The sample consisted of 2121 working women and men. Main- and mediation effects were investigated using hierarchical regression analysis. The results showed performance-based self-esteem mediated partially between the stressors and burnout. Performance-based self-esteem was the strongest predictor of burnout over time, followed by private life stressors. Women experienced more work stress than did men. Men had stronger associations between work stressors and burnout, while women had stronger associations between performance-based self-esteem and burnout. Individual characteristics along with both private life and work stressors are important predictors of burnout. Factors associated with burnout differ somewhat between women and men.
Zamotaev, Iu N; Enikeev, A Kh
2009-01-01
The aim of this work was to study psychophysiological functions in HD subjects during strenuous conveyor-belt work. It involved 225 participants of whom 195 presented with different stages of HD. Group 1 (n = 65) included patients with prehypertension, group 2 (n = 69) with stage 1 HD, group 3 (n = 61) with stage II HD. Control group comprised 30 healthy subjects. The groups were matched for clinical and demographic characteristics. It was shown that performance efficiency of the conveyor-belt workers decreased with increasing HD severity. Mental functioning was the first to be affected suggesting impairment of sensorimotor coordination and attention. Moreover, the performance correlated with the patients" age and length of work. The worst results of simple and complex visual-motor reaction time tests were obtained in patients above 40 years with more than 10 years" conveyor-work experience. Close relation of performance efficiency to psychosomatic condition reflects interplay of regulatory mechanisms responsible for optimal adaptation of the organism to strenuous work.
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…
ERIC Educational Resources Information Center
Zalbidea, Janire
2017-01-01
The present study explores the independent and interactive effects of task complexity and task modality on linguistic dimensions of second language (L2) performance and investigates how these effects are modulated by individual differences in working memory capacity. Thirty-two intermediate learners of L2 Spanish completed less and more complex…
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…
Modality dependence and intermodal transfer in the Corsi Spatial Sequence Task: Screen vs. Floor.
Röser, Andrea; Hardiess, Gregor; Mallot, Hanspeter A
2016-07-01
Four versions of the Corsi Spatial Sequence Task (CSST) were tested in a complete within-subject design, investigating whether participants' performance depends on the modality of task presentation and reproduction that put different demands on spatial processing. Presentation of the sequence (encoding phase) and the reproduction (recall phase) were each carried out either on a computer screen or on the floor of a room, involving actual walking in the recall phase. Combinations of the two different encoding and recall procedures result in the modality conditions Screen-Screen, Screen-Floor, Floor-Screen, and Floor-Floor. Results show the expected decrease in performance with increasing sequence length, which is likely due to processing limitations of working memory. We also found differences in performance between the modality conditions indicating different involvements of spatial working memory processes. Participants performed best in the Screen-Screen modality condition. Floor-Screen and Floor-Floor modality conditions require additional working memory resources for reference frame transformation and spatial updating, respectively; the resulting impairment of the performance was about the same in these two conditions. Finally, the Screen-Floor modality condition requires both types of additional spatial demands and led to the poorest performance. Therefore, we suggest that besides the well-known spatial requirements of CSST, additional working memory resources are demanded in walking CSST supporting processes such as spatial updating, mental rotation, reference frame transformation, and the control of walking itself.
The presentation builds on the work presented last year at the 14th CMAS meeting and it is applied to the work performed in the context of the AQMEII-HTAP collaboration. The analysis is conducted within the framework of the third phase of AQMEII (Air Quality Model Evaluation Inte...
Ego Depletion Does Not Interfere With Working Memory Performance.
Singh, Ranjit K; Göritz, Anja S
2018-01-01
Ego depletion happens if exerting self-control reduces a person's capacity to subsequently control themselves. Previous research has suggested that ego depletion not only interferes with subsequent self-control but also with working memory. However, recent meta-analytical evidence casts doubt onto this. The present study tackles the question if ego depletion does interfere with working memory performance. We induced ego depletion in two ways: using an e-crossing task and using a Stroop task. We then measured working memory performance using the letter-number sequencing task. There was no evidence of ego depletion interfering with working memory performance. Several aspects of our study render this null finding highly robust. We had a large and heterogeneous sample of N = 1,385, which provided sufficient power. We deployed established depletion tasks from two task families (e-crossing task and Stroop), thus making it less likely that the null finding is due to a specific depletion paradigm. We derived several performance scores from the working memory task and ran different analyses to maximize the chances of finding an effect. Lastly, we controlled for two potential moderators, the implicit theories about willpower and dispositional self-control capacity, to ensure that a possible effect on working memory is not obscured by an interaction effect. In sum, this experiment strengthens the position that ego depletion works but does not affect working memory performance.
Ego Depletion Does Not Interfere With Working Memory Performance
Singh, Ranjit K.; Göritz, Anja S.
2018-01-01
Ego depletion happens if exerting self-control reduces a person’s capacity to subsequently control themselves. Previous research has suggested that ego depletion not only interferes with subsequent self-control but also with working memory. However, recent meta-analytical evidence casts doubt onto this. The present study tackles the question if ego depletion does interfere with working memory performance. We induced ego depletion in two ways: using an e-crossing task and using a Stroop task. We then measured working memory performance using the letter-number sequencing task. There was no evidence of ego depletion interfering with working memory performance. Several aspects of our study render this null finding highly robust. We had a large and heterogeneous sample of N = 1,385, which provided sufficient power. We deployed established depletion tasks from two task families (e-crossing task and Stroop), thus making it less likely that the null finding is due to a specific depletion paradigm. We derived several performance scores from the working memory task and ran different analyses to maximize the chances of finding an effect. Lastly, we controlled for two potential moderators, the implicit theories about willpower and dispositional self-control capacity, to ensure that a possible effect on working memory is not obscured by an interaction effect. In sum, this experiment strengthens the position that ego depletion works but does not affect working memory performance. PMID:29706923
Productive and counterproductive job crafting: A daily diary study.
Demerouti, Evangelia; Bakker, Arnold B; Halbesleben, Jonathon R B
2015-10-01
The present study aims to uncover the way daily job crafting influences daily job performance (i.e., task performance, altruism, and counterproductive work behavior). Job crafting was conceptualized as "seeking resources," "seeking challenges," and "reducing demands" and viewed as strategies individuals use to optimize their job characteristics. We hypothesized that daily job crafting relates to daily job demands and resources (work pressure and autonomy), which consequently relate to daily work engagement and exhaustion and ultimately to job performance. A sample of 95 employees filled in a quantitative diary for 5 consecutive working days (n occasions = 475). We predicted and found that daily seeking resources was positively associated with daily task performance because daily autonomy and work engagement increased. In contrast, daily reducing demands was detrimental for daily task performance and altruism, because employees lower their daily workload and consequently their engagement and exhaustion, respectively. Only daily seeking challenges was positively (rather than negatively) associated with daily counterproductive behavior. We conclude that employee job crafting can have both beneficial and detrimental effects on job performance. (c) 2015 APA, all rights reserved).
The Motivation-Cognition Interface in Learning and Decision-Making.
Maddox, W Todd; Markman, Arthur B
2010-04-01
In this article we discuss how incentive motivations and task demands affect performance. We present a three-factor framework that suggests that performance is determined from the interaction of global incentives, local incentives, and the psychological processes needed to achieve optimal task performance. We review work that examines the implications of the motivation-cognition interface in classification, choice and on phenomena such as stereotype threat and performance pressure. We show that under some conditions stereotype threat and pressure accentuate performance. We discuss the implications of this work for neuropsychological assessment, and outline a number of challenges for future research.
Hofmans, Joeri; Debusscher, Jonas; Dóci, Edina; Spanouli, Andromachi; De Fruyt, Filip
2015-01-01
Whereas several studies have demonstrated that core self-evaluations (CSE)–or one’s appraisals about one’s own self-worth, capabilities, and competences–relate to job outcomes, less is known about the mechanisms underlying these relationships. In the present study, we address this issue by examining the role of within- and between-person variation in CSE in the relationship between work pressure and task performance. We hypothesized that (a) work pressure relates to task performance in a curvilinear way, (b) state CSE mediates the curvilinear relationship between work pressure and task performance, and (c) the relationship between work pressure and state CSE is moderated by trait CSE. Our hypotheses were tested via a 10-day daily diary study with 55 employees in which trait CSE was measured at baseline, while work pressure, task performance, and state CSE were assessed on a daily basis. Bayesian multilevel path analysis showed that work pressure affects task performance via state CSE, with state CSE increasing as long as the employee feels that (s)he is able to handle the work pressure, while it decreases when the level of work pressure exceeds the employees’ coping abilities. Moreover, we found that for people low on trait CSE, the depleting effect of work pressure via state CSE happens for low levels of work pressure, while for people high in trait CSE the depleting effect is located at high levels of work pressure. Together, our findings suggest that the impact of work pressure on task performance is driven by a complex interplay of between- and within-person differences in CSE. PMID:26579053
Working memory, long-term memory, and medial temporal lobe function
Jeneson, Annette; Squire, Larry R.
2012-01-01
Early studies of memory-impaired patients with medial temporal lobe (MTL) damage led to the view that the hippocampus and related MTL structures are involved in the formation of long-term memory and that immediate memory and working memory are independent of these structures. This traditional idea has recently been revisited. Impaired performance in patients with MTL lesions on tasks with short retention intervals, or no retention interval, and neuroimaging findings with similar tasks have been interpreted to mean that the MTL is sometimes needed for working memory and possibly even for visual perception itself. We present a reappraisal of this interpretation. Our main conclusion is that, if the material to be learned exceeds working memory capacity, if the material is difficult to rehearse, or if attention is diverted, performance depends on long-term memory even when the retention interval is brief. This fundamental notion is better captured by the terms subspan memory and supraspan memory than by the terms short-term memory and long-term memory. We propose methods for determining when performance on short-delay tasks must depend on long-term (supraspan) memory and suggest that MTL lesions impair performance only when immediate memory and working memory are insufficient to support performance. In neuroimaging studies, MTL activity during encoding is influenced by the memory load and correlates positively with long-term retention of the material that was presented. The most parsimonious and consistent interpretation of all the data is that subspan memoranda are supported by immediate memory and working memory and are independent of the MTL. PMID:22180053
The Complete Toolkit for Building High-Performance Work Teams.
ERIC Educational Resources Information Center
Golden, Nancy; Gall, Joyce P.
This workbook is designed for leaders and members of work teams in educational and social-service systems. It presents in a systematic fashion a set of tested facilitation tools that will allow teams to work more efficiently and harmoniously, enabling them to achieve their goals, to deal directly with both personal and work-related issues that…
ERIC Educational Resources Information Center
Schlechty, Phillip C.
This book, which is a companion to the books, "Shaking up the Schoolhouse" and "Inventing Better Schools," presents the Working on the Work (WOW) framework for improving student performance by improving the quality of schoolwork. Field-tested in schools nationwide, the framework describes the 12 essential components of a WOW…
Construction schedules slack time minimizing
NASA Astrophysics Data System (ADS)
Krzemiński, Michał
2017-07-01
The article presents two copyright models for minimizing downtime working brigades. Models have been developed for construction schedules performed using the method of work uniform. Application of flow shop models is possible and useful for the implementation of large objects, which can be divided into plots. The article also presents a condition describing gives which model should be used, as well as a brief example of optimization schedule. The optimization results confirm the legitimacy of the work on the newly-developed models.
Raman Laser Spectrometer Development for ExoMars
NASA Astrophysics Data System (ADS)
Pérez, C.; Colombo, M.; Díaz, C.; Santamaría, P.; Ingley, R.; Parrot, Y.; Maurice, S.; Popp, J.; Tarcea, N.; Edwards, H. G. M.
2013-09-01
The Raman Laser Spectrometer is one of the Pasteur Payload instruments, within the ESA's ExoMars mission. The aim of the work presented here is to provide a summary of the instrument design and performances. For that the instrument current characteristics and performances, and its technological ass assessment program main results are presented and discussed.
Neves, Robson da Fonseca; Nunes, Mônica de Oliveira; Magalhães, Lilian
2015-11-01
Mental disorders cause impact in the work environment. Investigations of interaction among stakeholders who are involved in the return to work are scarce. Meta-ethnography serves to synthesize qualitative studies by means of ongoing interpretation and comparison of the ideas presented in the articles. The goal of this study is to present a meta-ethnography of the interactions among the stakeholders involved in the return to work process after leave of absence due to mental disorders. It aims: (1) to investigate the interactions among stakeholders involved in return to work; (2) to identify enablers or obstacles for the return to work. The database search found 619 articles, 16 of which met the inclusion criteria. Analysis of the articles revealed six second-order concepts that resulted in two syntheses. The first is about performance ethos in the return to work, and the second shows return to work as a catalyst of new life styles. Models that favor the worker's performance ethos, as well as a perspective oriented by psychosocial aspects may enable return to work practices after leave of absence due to mental disorders.
El-Wakeel, Amr S; Mohammed, Nazmi A; Aly, Moustafa H
2016-09-10
In this work, a free space optical communication (FSO) link is proposed and utilized to explore and evaluate the FSO link performance under the joint occurrence of the atmospheric scattering and turbulence phenomena for 850 and 1550 nm operation. Diffraction and nondiffraction-limited systems are presented and evaluated for both wavelengths' operation, considering far-field conditions under different link distances. Bit error rate, pointing error angles, beam divergence angles, and link distance are the main performance indicators that are used to evaluate and compare the link performance under different system configurations and atmospheric phenomena combinations. A detailed study is performed to provide the merits of this work. For both far-field diffraction-limited and nondiffraction-limited systems, it is concluded that 1550 nm system operation is better than 850 nm for the whole presented joint occurrences of atmospheric scattering and turbulence.
Greulich, Simon; Steubing, Hannah; Birkmeier, Stefan; Grün, Stefan; Bentz, Kerstin; Sechtem, Udo; Mahrholdt, Heiko
2015-11-05
The diagnostic performance of adenosine stress cardiovascular magnetic resonance (CMR) in patients with arrhythmias presenting for work-up of suspected or known CAD is largely unknown, since most CMR studies currently available exclude arrhythmic patients from analysis fearing gating problems, or other artifacts will impair image quality. The primary aim of our study was to evaluate the diagnostic performance of adenosine stress CMR for detection of significant coronary stenosis in patients with arrhythmia presenting for 1) work-up of suspected coronary artery disease (CAD), or 2) work-up of ischemia in known CAD. Patients with arrhythmia referred for work-up of suspected CAD or work-up of ischemia in known CAD undergoing adenosine stress CMR were included if they had coronary angiography within four weeks of CMR. One hundred fifty-nine patients were included (n = 64 atrial fibrillation, n = 87 frequent ventricular extrasystoles, n = 8 frequent supraventricular extrasystoles). Of these, n = 72 had suspected CAD, and n = 87 had known CAD. Diagnostic accuracy of the adenosine stress CMR for detection of significant CAD was 73 % for the entire population (sensitivity 72 %, specificity 76 %). Diagnostic accuracy was 75 % (sensitivity 80 %, specificity 74 %) in patients with suspected CAD, and 74 % (sensitivity 71 %, specificity 79 %) in the group with known CAD. For different types of arrhythmia, diagnostic accuracy of CMR was 70 % in the atrial fibrillation group, and 79 % in patients with ventricular extrasystoles. On a per coronary territory analysis, diagnostic accuracy of CMR was 77 % for stenosis of the left and 82 % for stenosis of the right coronary artery. The present data demonstrates good diagnostic performance of adenosine stress CMR for detection of significant coronary stenosis in patients with arrhythmia presenting for work-up of suspected CAD, or work-up of ischemia in known CAD. This holds true for a per patient, as well as for a per coronary territory analysis.
The Case for Unit-Based Teams: A Model for Front-line Engagement and Performance Improvement
Cohen, Paul M; Ptaskiewicz, Mark; Mipos, Debra
2010-01-01
Unit-based teams (UBTs)—defined as natural work groups of physicians, managers, and frontline staff who work collaboratively to solve problems, improve performance, and enhance quality—were established by the 2005 national agreement between Kaiser Permanente (KP) and the Coalition of KP Unions. They use established performance-improvement techniques and employee-engagement principles (including social-movement theory) to achieve clinical and operational goals. UBT members identify performance gaps and opportunities within their purview—issues they can address in the course of the day-to-day work, such as workflow or process improvement. By focusing on clear, agreed-on goals, UBTs encourage greater accountability and allow members to perform their full scope of work. UBTs are designed to deliver measurable benefits in clinical outcomes and operations, patient-experience enhancements, and physician-team performance or work life. For many physicians, UBTs will require new ways of engaging with their teams. However, evidence suggests that with organizational and physician support, these teams can achieve their goals. This article presents case examples of successful UBTs' outcomes; physicians' comments on their experience working with teams; an overview of UBTs' employee-engagement principles; and advice on how physicians can support and participate in the work of such teams. PMID:20740124
The Structure of Working Memory Abilities across the Adult Life Span
Hale, Sandra; Rose, Nathan S.; Myerson, Joel; Strube, Michael J; Sommers, Mitchell; Tye-Murray, Nancy; Spehar, Brent
2010-01-01
The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20–89 (n=388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation. PMID:21299306
Cognitive impairments in former patients with work-related stress complaints - one year later.
Eskildsen, Anita; Andersen, Lars Peter; Pedersen, Anders Degn; Andersen, Johan Hviid
2016-11-01
Patients on sick leave due to work-related stress often present with cognitive impairments. The aim of this prospective cohort study was to examine the long-term consequences of prolonged work-related stress in terms of cognitive functioning one year after initial professional care seeking. We tested a group of patients with work-related stress with a comprehensive neuropsychological test battery at two occasions, one year apart. At both time points, we compared the performance of patients with healthy controls matched pairwise on sex, age and length of education. This paper presents the results from the one-year follow-up. When adjusting for practice effects, patients improved on measures of prospective memory and processing speed. However, patients continued to perform worse than controls on all tests, though only half of the comparisons reached statistical significance. The effect sizes of the differences between the two groups at one-year follow-up were small to medium. In conclusion, former patients with prolonged work-related stress improved, but they continued to perform worse than controls after one year. In the acute phase, the largest impairments were related to executive function and mental speed but at follow-up memory impairments also became apparent.
ERIC Educational Resources Information Center
Walker, Kenneth; Timmerman, Linda
1980-01-01
Describes Navarro College's (Corsicana, TX) program to reduce kilowatt hour consumption through alternative energy sources and energy costs through transition to a four-day/40-hour work week. Presents results of studies of employee performance levels, community response, and the cost effectiveness of the program. Lists benefits for the student,…
Improving Children's Working Memory and Classroom Performance
ERIC Educational Resources Information Center
St Clair-Thompson, Helen; Stevens, Ruth; Hunt, Alexandra; Bolder, Emma
2010-01-01
Previous research has demonstrated close relationships between working memory and children's scholastic attainment. The aim of the present study was to explore a method of improving working memory, using memory strategy training. Two hundred and fifty-four children aged five to eight years were tested on measures of the phonological loop,…
The Interaction of Concreteness and Phonological Similarity in Verbal Working Memory
ERIC Educational Resources Information Center
Acheson, Daniel J.; Postle, Bradley R.; MacDonald, Maryellen C.
2010-01-01
Although phonological representations have been a primary focus of verbal working memory research, lexical-semantic manipulations also influence performance. In the present study, the authors investigated whether a classic phenomenon in verbal working memory, the phonological similarity effect (PSE), is modulated by a lexical-semantic variable,…
NASA Technical Reports Server (NTRS)
Ownens, Albert K.; Lavelle, Thomas M.; Hervol, David S.
2010-01-01
A Dual Brayton Power Conversion System (DBPCS) has been tested at the NASA Glenn Research Center using Nitrogen (N2) as the working fluid. This system uses two closed Brayton cycle systems that share a common heat source and working fluid but are otherwise independent. This system has been modeled using the Numerical Propulsion System Simulation (NPSS) environment. This paper presents the results of a numerical study that investigated system performance changes resulting when the working fluid is changed from gaseous (N2) to gaseous carbon dioxide (CO2).
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.
Cardador, M Teresa
2014-01-01
Research on task significance and relational job design suggests that information from beneficiaries of one's work fosters perceptions of impact, and thus improved work outcomes. This paper presents results from a longitudinal field experiment examining the effect of another strategy for fostering perceptions of impact - engaging employees in regular reflection about how their work benefits others. With a sample of professionals from multiple organizations, this longitudinal study examined the effect on job performance and work-life conflict of both positive and negative impact reflection. Results show that negative impact reflection had a pronounced negative effect on job performance, but no effect on work-life conflict. Positive impact reflection had a weak positive effect on work-life conflict, but no significant effect on job performance. The direction of effects seen in the no intervention condition mirrored that of the negative impact reflection condition, suggesting a possible buffering effect for positive impact reflection. This research provides empirical and theoretical contributions to the literatures on relational job design and task significance.
Cardador, M. Teresa
2014-01-01
Research on task significance and relational job design suggests that information from beneficiaries of one’s work fosters perceptions of impact, and thus improved work outcomes. This paper presents results from a longitudinal field experiment examining the effect of another strategy for fostering perceptions of impact – engaging employees in regular reflection about how their work benefits others. With a sample of professionals from multiple organizations, this longitudinal study examined the effect on job performance and work-life conflict of both positive and negative impact reflection. Results show that negative impact reflection had a pronounced negative effect on job performance, but no effect on work-life conflict. Positive impact reflection had a weak positive effect on work-life conflict, but no significant effect on job performance. The direction of effects seen in the no intervention condition mirrored that of the negative impact reflection condition, suggesting a possible buffering effect for positive impact reflection. This research provides empirical and theoretical contributions to the literatures on relational job design and task significance. PMID:25505890
Holden, Richard J; Valdez, Rupa S; Schubert, Christiane C; Thompson, Morgan J; Hundt, Ann S
2017-01-01
Human factors/ergonomics recognises work as embedded in and shaped by levels of social, physical and organisational 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 identified 17 factors across physical, social and organisational 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 behaviour. 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. Practitioner Summary: Health-related activities of patients are embedded in and shaped by levels of social, physical and organisational context. This paper combined findings from three studies to specify 17 contextual or macroergonomic factors in home- and community-based work systems of chronically ill patients. These factors have research, design and policy implications.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Will, M.E.
1994-01-01
This report presents a standard method for deriving benchmarks for the purpose of ''contaminant screening,'' performed by comparing measured ambient concentrations of chemicals. The work was performed under Work Breakdown Structure 1.4.12.2.3.04.07.02 (Activity Data Sheet 8304). In addition, this report presents sets of data concerning the effects of chemicals in soil on invertebrates and soil microbial processes, benchmarks for chemicals potentially associated with United States Department of Energy sites, and literature describing the experiments from which data were drawn for benchmark derivation.
Electromagnetic Compatibility for the Space Shuttle
NASA Technical Reports Server (NTRS)
Scully, Robert C.
2004-01-01
This slide presentation reviews the Space Shuttle electromagnetic compatibility (EMC). It includes an overview of the design of the shuttle with the areas that are of concern for the electromagnetic compatibility. It includes discussion of classical electromagnetic interference (EMI) and the work performed to control the electromagnetic interference. Another area of interest is electrostatic charging and the threat of electrostatic discharge and the attempts to reduce damage to the Shuttle from these possible hazards. The issue of electrical bonding is als reviewed. Lastly the presentation reviews the work performed to protect the shuttle from lightning, both in flight and on the ground.
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.
Performance of solar refrigerant ejector refrigerating machine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Al-Khalidy, N.A.H.
1997-12-31
In this work a detailed analysis for the ideal, theoretical, and experimental performance of a solar refrigerant ejector refrigerating machine is presented. A comparison of five refrigerants to select a desirable one for the system is made. The theoretical analysis showed that refrigerant R-113 is more suitable for use in the system. The influence of the boiler, condenser, and evaporator temperatures on system performance is investigated experimentally in a refrigerant ejector refrigerating machine using R-113 as a working refrigerant.
NASA Technical Reports Server (NTRS)
Smith, Jeffrey H.
1992-01-01
An approach is presented for selecting an appropriate work-system for performing construction and operations tasks by humans and telerobots. The decision to use extravehicular activity (EVA) performed by astronauts, extravehicular robotics (EVR), or a combination of EVA and EVR is determined by the ratio of the marginal costs of EVA, EVR, and IVA. The approach proposed here is useful for examining cost trade-offs between tasks and performing trade studies of task improvement techniques (human or telerobotic).
NASA Technical Reports Server (NTRS)
Rohlik, Harold E; Wintucky, William T; Scibbe, Herbert W
1957-01-01
Detailed design information including overall performance parameters, velocity diagrams, and blade surface velocities is presented. Experimental performance includes maps based on rating as well as total-pressure ratios showing the effect of exit whirl. Also included are results of surveys at the stator exit and downstream of the rotor at design speed and specific work. This information will be used as a standard for comparison with subsequent secondary-flow work.
Working memory capacity and the scope and control of attention.
Shipstead, Zach; Harrison, Tyler L; Engle, Randall W
2015-08-01
Complex span and visual arrays are two common measures of working memory capacity that are respectively treated as measures of attention control and storage capacity. A recent analysis of these tasks concluded that (1) complex span performance has a relatively stronger relationship to fluid intelligence and (2) this is due to the requirement that people engage control processes while performing this task. The present study examines the validity of these conclusions by examining two large data sets that include a more diverse set of visual arrays tasks and several measures of attention control. We conclude that complex span and visual arrays account for similar amounts of variance in fluid intelligence. The disparity relative to the earlier analysis is attributed to the present study involving a more complete measure of the latent ability underlying the performance of visual arrays. Moreover, we find that both types of working memory task have strong relationships to attention control. This indicates that the ability to engage attention in a controlled manner is a critical aspect of working memory capacity, regardless of the type of task that is used to measure this construct.
Chevalier, Nicolas; James, Tiffany D; Wiebe, Sandra A; Nelson, Jennifer Mize; Espy, Kimberly Andrews
2014-07-01
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. Children were assessed longitudinally at 7 time points between 3 and 10 years of age. Twenty-one young adults also completed the same task. Proactive response sequence planning was assessed by comparing recall durations for the 1st item (preparatory interval) and subsequent items. At preschool age, the preparatory interval was generally shorter than subsequent item recall durations, whereas it was systematically longer during elementary school and in adults. Although children mostly approached the task reactively at preschool, they proactively planned response sequences with increasing efficiency from age 7 on, like adults. These findings clarify the nature of the changes in executive control that support working memory performance with age. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
ERIC Educational Resources Information Center
Unsworth, Nash
2016-01-01
The relation between working memory capacity (WMC) and recall from long-term memory (LTM) was examined in the current study. Participants performed multiple measures of delayed free recall varying in presentation duration and self-reported their strategy usage after each task. Participants also performed multiple measures of WMC. The results…
77 FR 38022 - Determination of Reasonable Rates and Terms for Noncommercial Broadcasting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-26
... submitted no later than July 26, 2012. List of Subjects in 37 CFR Part 381 Copyright, Music, Radio... presentation of PBS: 2013-2017 $232.18 (2) For performance of such a work as background or theme music in a PBS...: 2013-2017 $19.84 (4) For performance of such a work as background or theme music in a program of a...
MacNamara, Annmarie; Schmidt, Joseph; Zelinsky, Gregory J; Hajcak, Greg
2012-12-01
Working memory load reduces the late positive potential (LPP), consistent with the notion that functional activation of the DLPFC attenuates neural indices of sustained attention. Visual attention also modulates the LPP. In the present study, we sought to determine whether working memory load might exert its influence on ERPs by reducing fixations to arousing picture regions. We simultaneously recorded eye-tracking and EEG while participants performed a working memory task interspersed with the presentation of task-irrelevant fearful and neutral faces. As expected, fearful compared to neutral faces elicited larger N170 and LPP amplitudes; in addition, working memory load reduced the N170 and the LPP. Participants made more fixations to arousing regions of neutral faces and faces presented under high working memory load. Therefore, working memory load did not induce avoidance of arousing picture regions and visual attention cannot explain load effects on the N170 and LPP. Copyright © 2012 Elsevier B.V. All rights reserved.
Towards Verification and Validation for Increased Autonomy
NASA Technical Reports Server (NTRS)
Giannakopoulou, Dimitra
2017-01-01
This presentation goes over the work we have performed over the last few years on verification and validation of the next generation onboard collision avoidance system, ACAS X, for commercial aircraft. It describes our work on probabilistic verification and synthesis of the model that ACAS X is based on, and goes on to the validation of that model with respect to actual simulation and flight data. The presentation then moves on to identify the characteristics of ACAS X that are related to autonomy and to discuss the challenges that autonomy pauses on VV. All work presented has already been published.
Parallel Work of CO2 Ejectors Installed in a Multi-Ejector Module of Refrigeration System
NASA Astrophysics Data System (ADS)
Bodys, Jakub; Palacz, Michal; Haida, Michal; Smolka, Jacek; Nowak, Andrzej J.; Banasiak, Krzysztof; Hafner, Armin
2016-09-01
A performance analysis on of fixed ejectors installed in a multi-ejector module in a CO2 refrigeration system is presented in this study. The serial and the parallel work of four fixed-geometry units that compose the multi-ejector pack was carried out. The executed numerical simulations were performed with the use of validated Homogeneous Equilibrium Model (HEM). The computational tool ejectorPL for typical transcritical parameters at the motive nozzle were used in all the tests. A wide range of the operating conditions for supermarket applications in three different European climate zones were taken into consideration. The obtained results present the high and stable performance of all the ejectors in the multi-ejector pack.
High energy PIXE: A tool to characterize multi-layer thick samples
NASA Astrophysics Data System (ADS)
Subercaze, A.; Koumeir, C.; Métivier, V.; Servagent, N.; Guertin, A.; Haddad, F.
2018-02-01
High energy PIXE is a useful and non-destructive tool to characterize multi-layer thick samples such as cultural heritage objects. In a previous work, we demonstrated the possibility to perform quantitative analysis of simple multi-layer samples using high energy PIXE, without any assumption on their composition. In this work an in-depth study of the parameters involved in the method previously published is proposed. Its extension to more complex samples with a repeated layer is also presented. Experiments have been performed at the ARRONAX cyclotron using 68 MeV protons. The thicknesses and sequences of a multi-layer sample including two different layers of the same element have been determined. Performances and limits of this method are presented and discussed.
Characterizing Detonating LX-17 Charges Crossing a Transverse Air Gap with Experiments and Modeling
NASA Astrophysics Data System (ADS)
Lauderbach, Lisa M.; Souers, P. Clark; Garcia, Frank; Vitello, Peter; Vandersall, Kevin S.
2009-06-01
Experiments were performed using detonating LX-17 (92.5% TATB, 7.5% Kel-f by weight) charges with various width transverse air gaps both with and without manganin peizoresistive in-situ gauges present. The experiments, performed with 25 mm diameter by 25 mm long LX-17 pellets with the transverse air gap in between, showed that transverse gaps up to about 3 mm could be present without causing the detonation wave to fail to continue as a detonation. A JWL++/Tarantula code was utilized to model the results and compare with the in-situ gauge records with reasonable agreement to the experimental data. This work will present the experimental details as well as comparison to the model results. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
NASA Astrophysics Data System (ADS)
Rahman, Md. Lutfor; Salsabil, Zaimaa; Yasmin, Nusrat; Nourin, Farah Nazifa; Ali, Mohammad
2016-07-01
This paper presents an experimental study of a closed loop Pulsating Heat Pipe (CLPHP) as the demand of smaller and effective heat transfer devices is increasing day by day. PHP is a two phase heat transfer device suited for heat transfer applications, especially suited for handling moderate to high heat fluxes in different applications. A copper made Pulsating Heat Pipe (PHP) of 250 mm length is used in this experimental work with 2 mm ID and 3 mm OD, closed end-to-end in 8 looped, evacuated and then partially filled with working fluids. The evaporation section is 50 mm, adiabatic section is 120 mm and condensation section is 80 mm. The performance characterization is done for two working fluids at Vertical (0°) orientations. The working fluids are Methanol and Ethanol and the filling ratios are 40%, 50%, 60% & 70% based on total volume, respectively. The results show that the influence of various parameters, the heat input flux, and different filling ratios on a heat transfer performance of CLPHP. Methanol shows better performance as working fluid in PHP than ethanol at present orientation for a wide range of heat inputs and can be used at high heat input conditions. Ethanol is better choice to be used in low heat input conditions.
Prehn, Kristin; Schulze, Lars; Rossmann, Sabine; Berger, Christoph; Vohs, Knut; Fleischer, Monika; Hauenstein, Karlheinz; Keiper, Peter; Domes, Gregor; Herpertz, Sabine C
2013-02-01
OBJECTIVE. In the present study, we aimed to investigate the influence of concurrently presented emotional stimuli on cognitive task processing in violent criminal offenders primarily characterized by affective instability. METHODS. Fifteen male criminal offenders with antisocial and borderline personality disorder (ASPD and BPD) and 17 healthy controls underwent functional magnetic resonance imaging (fMRI) while performing a working memory task with low and high working memory load. In a second experimental run, to investigate the interaction of emotion and cognition, we presented emotionally neutral, low, or high salient social scenes in the background of the task. RESULTS. During the memory task without pictures, both groups did not differ in general task performance and neural representation of working memory processes. During the memory task with emotional background pictures, however, ASPD-BPD subjects compared to healthy controls showed delayed responses and enhanced activation of the left amygdala in the presence of emotionally high salient pictures independent of working memory load. CONCLUSIONS. These results illustrate an interaction of emotion and cognition in affective instable individuals with enhanced reactivity to emotionally salient stimuli which might be an important factor regarding the understanding of aggressive and violent behaviour in these individuals.
Exploring work-related issues on corporate sustainability.
Brunoro, C M; Bolis, I; Sznelwar, L I
2015-01-01
In a research project about work-related issues and corporate sustainability conducted in Brazil, the goal was to better understand how work-related issues were addressed in the corporate context. Particularly, there are some specific initiatives that serve as guides to organizational decisions, which make their performance indicators for the context of corporate sustainability. 1) To explore the presence of work-related issues and their origins in corporate sustainability approach, analyzing a) corporate disclosures; b) sustainability guidelines that are identified as relevant in corporate disclosures; c) documents that are related to sustainable development and also identified as key-documents for these guidelines and initiatives. 2) To present the activity-centered ergonomics and psychodynamics of work contributions to work-related issues in a corporate sustainability approach. An exploratory study based on multiple sources of evidence that were performed from 2012 to 2013, including interviews with companies that engaged in corporate sustainability and document analysis using the content analysis approach. Work-related issues have been presented since the earliest sustainable development documents. It is feasible to construct an empirical framework for work-related issues and corporate sustainability approaches. 1) Although some authors argue that corporate sustainability has its roots based only on the environmental dimension, there is strong empirical evidence showing that social dimension aspects such as work-related issues have been present since the beginning. 2) Some indicators should be redesigned to more precisely translate the reality of some workplaces, particularly those indicators related to organizational design and mental health.
On the Nature of Forgetting and the Processing--Storage Relationship in Reading Span Performance
ERIC Educational Resources Information Center
Saito, Satoru; Miyake, Akira
2004-01-01
Four experiments examined the nature of forgetting and the processing--storage relationship during performance on a prevalent working memory task, the reading span test. Using two different presentation paradigms, Experiments 1 and 2 replicated Towse, Hitch, and Hutton's (1998, 2000) finding that the Short-Final lists, which presented a long…
Stenbäck, Victoria; Hällgren, Mathias; Lyxell, Björn; Larsby, Birgitta
2015-06-01
Cognitive functions and speech-recognition-in-noise were evaluated with a cognitive test battery, assessing response inhibition using the Hayling task, working memory capacity (WMC) and verbal information processing, and an auditory test of speech recognition. The cognitive tests were performed in silence whereas the speech recognition task was presented in noise. Thirty young normally-hearing individuals participated in the study. The aim of the study was to investigate one executive function, response inhibition, and whether it is related to individual working memory capacity (WMC), and how speech-recognition-in-noise relates to WMC and inhibitory control. The results showed a significant difference between initiation and response inhibition, suggesting that the Hayling task taps cognitive activity responsible for executive control. Our findings also suggest that high verbal ability was associated with better performance in the Hayling task. We also present findings suggesting that individuals who perform well on tasks involving response inhibition, and WMC, also perform well on a speech-in-noise task. Our findings indicate that capacity to resist semantic interference can be used to predict performance on speech-in-noise tasks. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.
Work Stress Interventions in Hospital Care: Effectiveness of the DISCovery Method
Niks, Irene; Gevers, Josette
2018-01-01
Effective interventions to prevent work stress and to improve health, well-being, and performance of employees are of the utmost importance. This quasi-experimental intervention study presents a specific method for diagnosis of psychosocial risk factors at work and subsequent development and implementation of tailored work stress interventions, the so-called DISCovery method. This method aims at improving employee health, well-being, and performance by optimizing the balance between job demands, job resources, and recovery from work. The aim of the study is to quantitatively assess the effectiveness of the DISCovery method in hospital care. Specifically, we used a three-wave longitudinal, quasi-experimental multiple-case study approach with intervention and comparison groups in health care work. Positive changes were found for members of the intervention groups, relative to members of the corresponding comparison groups, with respect to targeted work-related characteristics and targeted health, well-being, and performance outcomes. Overall, results lend support for the effectiveness of the DISCovery method in hospital care. PMID:29438350
Work Stress Interventions in Hospital Care: Effectiveness of the DISCovery Method.
Niks, Irene; de Jonge, Jan; Gevers, Josette; Houtman, Irene
2018-02-13
Effective interventions to prevent work stress and to improve health, well-being, and performance of employees are of the utmost importance. This quasi-experimental intervention study presents a specific method for diagnosis of psychosocial risk factors at work and subsequent development and implementation of tailored work stress interventions, the so-called DISCovery method. This method aims at improving employee health, well-being, and performance by optimizing the balance between job demands, job resources, and recovery from work. The aim of the study is to quantitatively assess the effectiveness of the DISCovery method in hospital care. Specifically, we used a three-wave longitudinal, quasi-experimental multiple-case study approach with intervention and comparison groups in health care work. Positive changes were found for members of the intervention groups, relative to members of the corresponding comparison groups, with respect to targeted work-related characteristics and targeted health, well-being, and performance outcomes. Overall, results lend support for the effectiveness of the DISCovery method in hospital care.
Influence of the cooling degree upon performances of internal combustion engine
NASA Astrophysics Data System (ADS)
Grǎdinariu, Andrei Cristian; Mihai, Ioan
2016-12-01
Up to present, air cooling systems still raise several unsolved problems due to conditions imposed by the environment in terms of temperature and pollution levels. The present paper investigates the impact of the engine cooling degree upon its performances, as important specific power is desired for as low as possible fuel consumption. A technical solution advanced by the authors[1], consists of constructing a bi-flux compressor, which can enhance the engine's performances. The bi-flux axial compressor accomplishes two major functions, that is it cools down the engine and it also turbocharges it. The present paper investigates the temperature changes corresponding to the fresh load, during the use of a bi-flux axial compressor. This compressor is economically simple, compact, and offers an optimal response at low rotational speeds of the engine, when two compression steps are used. The influence of the relative coefficient of air temperature drop upon working agent temperature at the intercooler exit is also investigated in the present work. The variation of the thermal load coefficient by report to the working agent temperature is also investigated during engine cooling. The variation of the average combustion temperature is analyzed in correlation to the thermal load coefficient and the temperatures of the working fluid at its exit from the cooling system. An exergetic analysis was conducted upon the influence of the cooling degree on the motor fluid and the gases resulted from the combustion process.
New technology in turbine aerodynamics.
NASA Technical Reports Server (NTRS)
Glassman, A. J.; Moffitt, T. P.
1972-01-01
Cursory review of some recent work that has been done in turbine aerodynamic research. Topics discussed include the aerodynamic effect of turbine coolant, high work-factor (ratio of stage work to square of blade speed) turbines, and computer methods for turbine design and performance prediction. Experimental cooled-turbine aerodynamics programs using two-dimensional cascades, full annular cascades, and cold rotating turbine stage tests are discussed with some typical results presented. Analytically predicted results for cooled blade performance are compared to experimental results. The problems and some of the current programs associated with the use of very high work factors for fan-drive turbines of high-bypass-ratio engines are discussed. Computer programs have been developed for turbine design-point performance, off-design performance, supersonic blade profile design, and the calculation of channel velocities for subsonic and transonic flowfields. The use of these programs for the design and analysis of axial and radial turbines is discussed.
Childhood Obesity and Academic Performance: The Role of Working Memory
Wu, Nan; Chen, Yulu; Yang, Jinhua; Li, Fei
2017-01-01
The present study examined the role of working memory in the association between childhood obesity and academic performance, and further determined whether memory deficits in obese children are domain-specific to certain tasks or domain-general. A total of 227 primary school students aged 10–13 years were analyzed for weight and height, of which 159 children (44 “obese,” 23 “overweight,” and 92 “normal weight”) filled out questionnaires on school performance and socioeconomic status. And then, all subjects finished three kinds of working memory tasks based on the digit memory task in 30 trials, which were image-generated with a series of numbers recall trial sets. After each trial set, subjects were given 5 s to recall and write down the numbers which hand appeared in the trial, in the inverse order in which they had appeared. The results showed there were significant academic performance differences among the three groups, with normal-weight children scoring higher than overweight and obese children after Bonferroni correction. A mediation model revealed a partial indirect effect of working memory in the relationship between obesity and academic performance. Although the performance of obese children in basic working memory tests was poorer than that of normal-weight children, they recalled more items than normal-weight children in working memory tasks involving with food/drink. Working memory deficits partially explain the poor academic performance of obese children. Those results indicated the obese children show domain-specific working memory deficits, whereas they recall more items than normal-weight children in working memory tasks associated with food/drink. PMID:28469593
Childhood Obesity and Academic Performance: The Role of Working Memory.
Wu, Nan; Chen, Yulu; Yang, Jinhua; Li, Fei
2017-01-01
The present study examined the role of working memory in the association between childhood obesity and academic performance, and further determined whether memory deficits in obese children are domain-specific to certain tasks or domain-general. A total of 227 primary school students aged 10-13 years were analyzed for weight and height, of which 159 children (44 "obese," 23 "overweight," and 92 "normal weight") filled out questionnaires on school performance and socioeconomic status. And then, all subjects finished three kinds of working memory tasks based on the digit memory task in 30 trials, which were image-generated with a series of numbers recall trial sets. After each trial set, subjects were given 5 s to recall and write down the numbers which hand appeared in the trial, in the inverse order in which they had appeared. The results showed there were significant academic performance differences among the three groups, with normal-weight children scoring higher than overweight and obese children after Bonferroni correction. A mediation model revealed a partial indirect effect of working memory in the relationship between obesity and academic performance. Although the performance of obese children in basic working memory tests was poorer than that of normal-weight children, they recalled more items than normal-weight children in working memory tasks involving with food/drink. Working memory deficits partially explain the poor academic performance of obese children. Those results indicated the obese children show domain-specific working memory deficits, whereas they recall more items than normal-weight children in working memory tasks associated with food/drink.
What Works, Works Everywhere: Q&A with Michael Barber
ERIC Educational Resources Information Center
Crow, Tracy
2009-01-01
This article presents an interview with Michael Barber, a partner at McKinsey & Company, leading its global education practice. He has been working on major challenges of performance, organization, and reform in government and the public services, especially education, in the U.S., U.K., and other countries. Barber was instrumental in preparing…
Ricker, Timothy J; Sandry, Joshua
2018-04-10
The presentation of a similar but irrelevant stimulus immediately following presentation of a memory item is called masking. Masking is known to reduce performance on working memory tests. This is the type of memory used to hold information in mind for brief periods of time for use in ongoing cognition. Two approaches to understanding masking effects have been proposed in different literatures. Working memory researchers often assume that the reduction in working memory performance after masking is because masking interferes with a transient sensory representation that is needed to complete consolidation into a working memory state. Researchers focused on the attentional blink, a finding that attention cannot be directed to new stimuli during working memory consolidation, have an alternative theory. Attentional blink researchers assume that masking slows the short-term consolidation process, thereby extending the length of the attentional blink. In two experiments, we contrast these two approaches to explaining masking effects and investigate the validity of both hypotheses. Some aspects of both approaches are validated, but neither theoretical perspective alone sufficiently explains the entire pattern of results. © 2018 New York Academy of Sciences.
Goble, Daniel J; Mousigian, Marianne A; Brown, Susan H
2012-01-01
Perceiving the positions and movements of one's body segments (i.e., proprioception) is critical for movement control. However, this ability declines with older age as has been demonstrated by joint angle matching paradigms in the absence of vision. The aim of the present study was to explore the extent to which reduced working memory and attentional load influence older adult proprioceptive matching performance. Older adults with relatively HIGH versus LOW working memory ability as determined by backward digit span and healthy younger adults, performed memory-based elbow position matching with and without attentional load (i.e., counting by 3 s) during target position encoding. Even without attentional load, older adults with LOW digit spans (i.e., 4 digits or less) had larger matching errors than younger adults. Further, LOW older adults made significantly greater errors when attentional loads were present during proprioceptive target encoding as compared to both younger and older adults with HIGH digit span scores (i.e., 5 digits or greater). These results extend previous position matching results that suggested greater errors in older adults were due to degraded input signals from peripheral mechanoreceptors. Specifically, the present work highlights the role cognitive factors play in the assessment of older adult proprioceptive acuity using memory-based matching paradigms. Older adults with LOW working memory appear prone to compromised proprioceptive encoding, especially when secondary cognitive tasks must be concurrently executed. This may ultimately result in poorer performance on various activities of daily living.
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
van Wingerden, Jessica; Poell, Rob F.
2017-01-01
The present study was designed to gain knowledge of the relationship between employees’ perceived opportunities to craft, their actual job crafting behavior and, in line with JD-R theory, subsequently their work engagement and performance. Although scholars have suggested that employees’ perceived opportunities to craft their job may predict their actual job crafting behavior, which may have consequences for their well-being and performance, no study has examined the relationships between these variables. We collected data among a heterogeneous group of Dutch employees (N = 2090). Participants of the study reported their perceived opportunities to craft, job crafting behavior, work engagement and performance. Results indicated that individuals who experience a high level of opportunities to craft reported higher levels of job crafting behavior. In turn, perceived opportunities to craft and job crafting behavior related to higher levels of work engagement and subsequently performance. We discuss the implications of these findings for theory and practice. PMID:29118729
van Wingerden, Jessica; Poell, Rob F
2017-01-01
The present study was designed to gain knowledge of the relationship between employees' perceived opportunities to craft, their actual job crafting behavior and, in line with JD-R theory, subsequently their work engagement and performance. Although scholars have suggested that employees' perceived opportunities to craft their job may predict their actual job crafting behavior, which may have consequences for their well-being and performance, no study has examined the relationships between these variables. We collected data among a heterogeneous group of Dutch employees ( N = 2090). Participants of the study reported their perceived opportunities to craft, job crafting behavior, work engagement and performance. Results indicated that individuals who experience a high level of opportunities to craft reported higher levels of job crafting behavior. In turn, perceived opportunities to craft and job crafting behavior related to higher levels of work engagement and subsequently performance. We discuss the implications of these findings for theory and practice.
Working memory plasticity and aging.
Rhodes, Rebecca E; Katz, Benjamin
2017-02-01
The present research explores how the trajectory of learning on a working memory task changes throughout the life span, and whether gains in working memory performance are exclusively a question of initial working memory capacity (WMC) or whether age exerts an independent effect. In a large, cross-sectional study of younger, middle-aged, and older adults, we examined learning on a widely used working memory task-the dual n-back task-over 20 sessions of practice. We found that, while all age groups improved on the task, older adults demonstrated less improvement on the task, and also reached a lower asymptotic maximum performance than younger adults. After controlling for initial WMC, we found that age exerted independent effects on training gains and asymptotic performance; older adults tended to improve less and reached lower levels of performance than younger adults. The difference between younger and older adults' rates of learning depended in part on initial WMC. These results suggest that age-related effects on working memory include not only effects on capacity, but also plasticity and the ability to improve on a task. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Work-related olfactory disorder: a case series and review.
Park, Soon Woo; Kang, Young Joong; Eom, Huisu; Cho, Hyun-Jin; Ahn, Jungho; Lee, Sang-Gil
2018-01-01
The olfactory bulb is anatomically exposed and thus can be directly damaged by external stimulation. This can occur as an occupational injury owing to contact with organic solvents or other causes. We present cases of eight patients who sustained occupation-related exposure to potentially toxic substances and later presented with signs and symptoms of anosmia. We examined the occupational and medical characteristics of the patients and evaluated their work-relatedness. Case 1: A 50-year-old man performed high-frequency heat treatments for approximately 11 years. He experienced decreased senses for olfaction and taste during the later years culminating in the diagnosis of anosmia after 3 years (high work-relatedness). Case 2: A 54-year-old man whose work involved exposure to various organic solvents, such as spray painting and application of paint and thinners for approximately 4 years, was subsequently diagnosed with anosmia based on rhinorrhea, headache, and loss of olfaction (high work-relatedness). Case 3: A 44-year-old-man who performed spray painting for approximately 17 years developed anosmia (high work-relatedness). Case 4: A 44-year-old man was involved in ship engine cleaning once a month, for approximately 7 h per cleaning session; he was diagnosed with anosmia based on loss of olfaction (low work-relatedness). Case 5: A 41-year-old man worked in ship building block construction for approximately 13 years; anosmia diagnosis was based on loss of olfaction (low work-relatedness). Case 6: A 47-year-old woman performed product inspection and labeling at a plant manufacturing automobile parts; anosmia diagnosis was based on decreased olfaction and taste (low work-relatedness). Case 7: A 50-year-old woman performed epoxy coating in a plant manufacturing automobile parts; anosmia diagnosis was based on diminishing olfaction (low work-relatedness). Case 8: A 57-year-old woman performed cleaning of the area where mobile phone parts were manufactured; anosmia diagnosis was based on diminishing olfaction (low work-relatedness). The study results confirmed work-relatedness when the subject was young, and the duration of exposure was long without any other cause of anosmia. Regarding compensation for occupational diseases, work-relatedness can be recognized as a relative concept.
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…
Kombeiz, Olga; Steidle, Anna
2018-03-01
Research has shown that colours influence motivation and cognitive performance. In achievement contexts, red evokes avoidance motivation that hinders creativity, while blue elicits an approach motivation that facilitates creativity. However, due to their position and mode of presentation, colours may convey a different message. Red accent lighting creates a cosy, friendly room atmosphere that may, even in an achievement context, elicit an approach rather than an avoidance motivation. Results (N = 146) showed that both blue and red accent light increased strategic approach motivation compared to white accent light. Moreover, through the heightened approach motivation, colourful accent light indirectly improved creative performance. Implications for future research on colour and practical implications for colour usage are discussed. Practitioner Summary: Designing work environments for creativity is a new topic in ergonomics research and practice. The present study demonstrates indirect effects of coloured accent light on creativity providing interesting possibilities for the design of workplaces for knowledge workers, classrooms and all other rooms in which people work on new ideas.
Assessment of nurses' work climate at Alexandria Main University Hospital.
Emam, Sanaa Abdel-aziz; Nabawy, Zeinab Mohamed; Mohamed, Azzaa Hassan; Sbeira, Walaa Hashem
2005-01-01
Work climate is indicative of how well the organization is realizing its full potential. An accurate assessment of work climate can identify the unnecessary obstacles to nurses interfering with their best performance. The present study aims to assess nurses' work climate at Alexandria Main University Hospital. The study sample included all nurses (N=400) who were working in inpatient medical and surgical units at the Alexandria Main University Hospital who were available at the time of data collection. A structured questionnaire was developed to assess nurses' perceptions regarding the dimensions of work climate. Data was collected by individual interview using the structured questionnaire. Results indicated that the highest percentages of nurses in medical and surgical units perceived that their work climate is characterized by good way of performance management, feeling of responsibility, warmth and supportive relationships, quality of communication, morale, organizational clarity and feeling of identity and belongness to the hospital. Nurses perceived that they are lacking work climate conducive to conflict resolution, participation in decision making, opportunity for training and development, fair rewards and recognition, calculated risks, sufficient resources, effective leadership and teamwork. There were no significant difference between nurses perceptions in medical and surgical units regarding all dimensions of work climate. The highest percentage of nurses in all units were satisfied only with the feeling of responsibility, way of performance management, and quality of communication. Conflict and identity were perceived as the most important areas that need improvement in the hospital. Based on the results recommendations were given to enhance work climate through designing compensation and recognition systems, and negotiate their requirements and accomplishment based on established standards and outcomes measures. Also, encouragement of and planning for participative decision making, teamwork, in-service training program and open communication are recommended to be present in the work units.
The Effectiveness of Practical Work in Lower Secondary School Mathematics: A Cultural Approach.
ERIC Educational Resources Information Center
Triadafillidis, T. A.
1996-01-01
Discusses reasons why practical work is used only sporadically in lower secondary school math classes. Presents results of a comparative study between Greece and Scotland, focusing on culture as a differentiating factor of students' performance. (AIM)
Elements of an Employee Motivation Program
ERIC Educational Resources Information Center
Ward, Ernest H.
1974-01-01
Ten elements which should be present in an employee motivation program are discussed in the context of achieving increased acceptance of organizational goals. They are: participation, performance measurement, knowledge of results, recognition; attitude measurement, communication, publicity, work assignment, work research, and supervisor motivation…
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.
Presentation from the Federal Green Challenge Webinar Strategies for Energy/Water Conservation and Waste Diversion. Learn how the U.S. General Services Administration Region 2 program works to improve building performance.
NASA Technical Reports Server (NTRS)
Arenstorf, Norbert S.; Jordan, Harry F.
1987-01-01
A barrier is a method for synchronizing a large number of concurrent computer processes. After considering some basic synchronization mechanisms, a collection of barrier algorithms with either linear or logarithmic depth are presented. A graphical model is described that profiles the execution of the barriers and other parallel programming constructs. This model shows how the interaction between the barrier algorithms and the work that they synchronize can impact their performance. One result is that logarithmic tree structured barriers show good performance when synchronizing fixed length work, while linear self-scheduled barriers show better performance when synchronizing fixed length work with an imbedded critical section. The linear barriers are better able to exploit the process skew associated with critical sections. Timing experiments, performed on an eighteen processor Flex/32 shared memory multiprocessor, that support these conclusions are detailed.
Performance optimization of a miniature Joule-Thomson cryocooler using numerical model
NASA Astrophysics Data System (ADS)
Ardhapurkar, P. M.; Atrey, M. D.
2014-09-01
The performance of a miniature Joule-Thomson cryocooler depends on the effectiveness of the heat exchanger. The heat exchanger used in such cryocooler is Hampson-type recuperative heat exchanger. The design of the efficient heat exchanger is crucial for the optimum performance of the cryocooler. In the present work, the heat exchanger is numerically simulated for the steady state conditions and the results are validated against the experimental data available from the literature. The area correction factor is identified for the calculation of effective heat transfer area which takes into account the effect of helical geometry. In order to get an optimum performance of the cryocoolers, operating parameters like mass flow rate, pressure and design parameters like heat exchanger length, helical diameter of coil, fin dimensions, fin density have to be identified. The present work systematically addresses this aspect of design for miniature J-T cryocooler.
NASA Astrophysics Data System (ADS)
Andrzejczyk, Rafał; Muszyński, Tomasz
2017-09-01
In this study, the influences of different parameters at performance two-phase closed thermosiphon (TPCT) was presented. It has been confirmed that the working fluid, as well as operating parameters and fill ratio, are very important factors in the performance of TPCT. The article shows characteristics of gravitational tube geometries, as well as the technical characteristic of the most important system components, i.e., the evaporator/condenser. The experiment's plan and the results of it for the two-phase thermosiphon for both evaluated geometries with varying thermal and fluid flow parameters are presented. Experiments were performed for the most perspective working fluids, namely: water, R134a, SES36, ethanol and HFE7100. Obtained research proves the possibility to use TPCT for heat recovery from the industrial waste water.
NASA Technical Reports Server (NTRS)
Jenkins, R. M.
1983-01-01
The present effort represents an extension of previous work wherein a calculation model for performing rapid pitchline optimization of axial gas turbine geometry, including blade profiles, is developed. The model requires no specification of geometric constraints. Output includes aerodynamic performance (adiabatic efficiency), hub-tip flow-path geometry, blade chords, and estimates of blade shape. Presented herein is a verification of the aerodynamic performance portion of the model, whereby detailed turbine test-rig data, including rig geometry, is input to the model to determine whether tested performance can be predicted. An array of seven (7) NASA single-stage axial gas turbine configurations is investigated, ranging in size from 0.6 kg/s to 63.8 kg/s mass flow and in specific work output from 153 J/g to 558 J/g at design (hot) conditions; stage loading factor ranges from 1.15 to 4.66.
Parallel File System I/O Performance Testing On LANL Clusters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wiens, Isaac Christian; Green, Jennifer Kathleen
2016-08-18
These are slides from a presentation on parallel file system I/O performance testing on LANL clusters. I/O is a known bottleneck for HPC applications. Performance optimization of I/O is often required. This summer project entailed integrating IOR under Pavilion and automating the results analysis. The slides cover the following topics: scope of the work, tools utilized, IOR-Pavilion test workflow, build script, IOR parameters, how parameters are passed to IOR, *run_ior: functionality, Python IOR-Output Parser, Splunk data format, Splunk dashboard and features, and future work.
Creating Workplaces Where People Can Think: Cognitive Ergonomics.
ERIC Educational Resources Information Center
Kearny, Lynn; Smith, Phyl
1999-01-01
Presents ideas about how the workplace affects job performance, how to diagnose workplace-related problems, and how to make modest improvements. Highlights include: workplace-imposed limits on performance; the mental and physical steps of work; screening behavior; how adaptation interferes with performance; task- and human-based workspaces;…
Electric Motor Thermal Management R&D (Presentation)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bennion, K.
2014-11-01
Thermal constraints place significant limitations on how electric motors ultimately perform. Without the ability to remove heat, the motor cannot operate without sacrificing performance, efficiency, and reliability. Finite element analysis and computational fluid dynamics modeling approaches are being increasingly utilized in the design and analysis of electric motors. As the models become more sophisticated, it is important to have detailed and accurate knowledge of both the passive thermal performance and the active cooling performance. In this work, we provide an overview of research characterizing both passive and active thermal elements related to electric motor thermal management. To better characterize themore » passive thermal performance, the effective thermal properties and inter-lamination thermal contact resistances were measured for different stator lamination materials. The active cooling performance of automatic transmission fluid (ATF) jets was also measured to better understand the heat transfer coefficients of ATF impinging on motor copper windings. Ford's Mercon LV was the ATF evaluated in this study. The presentation provides an overview of prior work with a focus on describing future plans for research to be performed during FY15.« less
Work readiness tools for young adults with chronic conditions.
Metzinger, Courtney; Berg, Christine
2015-01-01
Young adults with chronic health conditions can experience barriers to work performance, ability, and their present and future worker roles. Work readiness resources can expand individuals' work skills, abilities, and interests. Five work readiness tools are presented (1) building an occupational profile, (2) generating environmental strategies, (3) on-the-job strategy use, and exploration of online tools (4) O*NET® and (5) O*NET® Interest Profiler, along with two theories (Knowles's Andragogy and Lawton's Ecological Model) to guide tool use. Use of these tools can assist young adults to better manage their health and expand their vocational identities for success at work. These approaches and tools support health professionals, community partners, and vocational organizations in their efforts to help young adults with chronic conditions.
The Worker and the Job: Coping with Change.
ERIC Educational Resources Information Center
Rosow, Jerome M., Ed.
The collection of essays presents the pros and cons of the assertation "improving the place, the organization, and the nature of work can lead to better work performance and a better quality of life in the society." In the overview section, Daniel Yankelovich discusses man and his relationship to his family and society at large, with work as the…
Effects of Individual Differences in Working Memory on Plan Presentational Choices
Tintarev, Nava; Masthoff, Judith
2016-01-01
This paper addresses research questions that are central to the area of visualization interfaces for decision support: (RQ1) whether individual user differences in working memory should be considered when choosing how to present visualizations; (RQ2) how to present the visualization to support effective decision making and processing; and (RQ3) how to evaluate the effectiveness of presentational choices. These questions are addressed in the context of presenting plans, or sequences of actions, to users. The experiments are conducted in several domains, and the findings are relevant to applications such as semi-autonomous systems in logistics. That is, scenarios that require the attention of humans who are likely to be interrupted, and require good performance but are not time critical. Following a literature review of different types of individual differences in users that have been found to affect the effectiveness of presentational choices, we consider specifically the influence of individuals' working memory (RQ1). The review also considers metrics used to evaluate presentational choices, and types of presentational choices considered. As for presentational choices (RQ2), we consider a number of variants including interactivity, aggregation, layout, and emphasis. Finally, to evaluate the effectiveness of plan presentational choices (RQ3) we adopt a layered-evaluation approach and measure performance in a dual task paradigm, involving both task interleaving and evaluation of situational awareness. This novel methodology for evaluating visualizations is employed in a series of experiments investigating presentational choices for a plan. A key finding is that emphasizing steps (by highlighting borders) can improve effectiveness on a primary task, but only when controlling for individual variation in working memory. PMID:27899905
Effects of Individual Differences in Working Memory on Plan Presentational Choices.
Tintarev, Nava; Masthoff, Judith
2016-01-01
This paper addresses research questions that are central to the area of visualization interfaces for decision support: (RQ1) whether individual user differences in working memory should be considered when choosing how to present visualizations; (RQ2) how to present the visualization to support effective decision making and processing; and (RQ3) how to evaluate the effectiveness of presentational choices. These questions are addressed in the context of presenting plans, or sequences of actions, to users. The experiments are conducted in several domains, and the findings are relevant to applications such as semi-autonomous systems in logistics. That is, scenarios that require the attention of humans who are likely to be interrupted, and require good performance but are not time critical. Following a literature review of different types of individual differences in users that have been found to affect the effectiveness of presentational choices, we consider specifically the influence of individuals' working memory (RQ1). The review also considers metrics used to evaluate presentational choices, and types of presentational choices considered. As for presentational choices (RQ2), we consider a number of variants including interactivity, aggregation, layout, and emphasis. Finally, to evaluate the effectiveness of plan presentational choices (RQ3) we adopt a layered-evaluation approach and measure performance in a dual task paradigm, involving both task interleaving and evaluation of situational awareness. This novel methodology for evaluating visualizations is employed in a series of experiments investigating presentational choices for a plan. A key finding is that emphasizing steps (by highlighting borders) can improve effectiveness on a primary task, but only when controlling for individual variation in working memory.
Gilchrist, Amanda L; Duarte, Audrey; Verhaeghen, Paul
2016-01-01
Research with younger adults has shown that retrospective cues can be used to orient top-down attention toward relevant items in working memory. We examined whether older adults could take advantage of these cues to improve memory performance. Younger and older adults were presented with visual arrays of five colored shapes; during maintenance, participants were presented either with an informative cue based on an object feature (here, object shape or color) that would be probed, or with an uninformative, neutral cue. Although older adults were less accurate overall, both age groups benefited from the presentation of an informative, feature-based cue relative to a neutral cue. Surprisingly, we also observed differences in the effectiveness of shape versus color cues and their effects upon post-cue memory load. These results suggest that older adults can use top-down attention to remove irrelevant items from visual working memory, provided that task-relevant features function as cues.
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.
Shimazu, Akihito; Schaufeli, Wilmar B
2009-10-01
The aim of the present study is to demonstrate the empirical distinctiveness of workaholism and work engagement by examining their relationships with well-being in a sample of 776 Japanese employees. We expected that workaholism is associated with unwell-being (i.e., high psychological distress and physical complaints, low job and family satisfaction, and low job performance), whereas work engagement is associated with well-being. Well-validated questionnaires were used to measure workaholism (DUWAS), work engagement (UWES), and well-being (BJSQ, HPQ). Structural Equation Modeling showed that, as expected, workaholism was positively associated with ill-health (i.e., psychological distress and physical complaints) and negatively associated with life satisfaction (i.e., job and family satisfaction) and job performance. In contrast, work engagement was negatively associated with ill-health and positively associated with life satisfaction and job performance. These findings suggest that workaholism and work engagement are two different kinds of concepts, which are negatively and positively related to various indicators of well-being, respectively.
Environmental Physiology at the Johnson Space Center: Past, Present, and Future
NASA Technical Reports Server (NTRS)
Conkin, Johnny
2007-01-01
This viewgraph presentation reviews the work in environmental physiology done at Johnson Space Center (JSC). The work is aimed at keeping astronauts healthy. This is a different approach than treating the sick, and is more of an occupational health model. The reduction of risks is the main emphasis for this work. They emphasis is to reduce the risk of decompression sickness (DCS) and acute mountain sickness (AMS). The work in environmental physiology encompasses the following areas: (1) Pressure: hypobaric and hyperbaric (2) Gases: hypoxia and hyperoxia, hypercapnia--closed space issues, inert gas physiology / respiration (3) Temperature: hypothermia and hyperthermia, thermal comfort, Protective clothing diving, aviation, mountaineering, and space (4) Acceleration (5) Noise and Vibration (6) Exercise / Performance (6) Acclimatization / Adaptation: engineering solutions when necessary. This presentation reviews the work done at JSC in the areas of DCS and AMS.
Green Propulsion Advancement and Infusion
NASA Technical Reports Server (NTRS)
Mulkey, Henry W.; Maynard, Andrew P.; Anflo, Kjell
2018-01-01
All space missions benefit from increased propulsion system performance, allowing lower spacecraft launch mass, larger scientific payloads, or extended on-orbit lifetimes. Likewise, long-term storable liquid propellant candidates that offer significant reduction in personnel hazards and shorter payload processing schedules present a more attractive propulsion subsystem solution to spacecraft builders. Aiming to reduce risk to potential infusion missions and fully comprehend the alternative propellant performance, the work presented herein represents many years of development and collaborative efforts to successfully align higher performance, low toxicity green propellants into NASA Goddard Space Flight Center (GSFC) missions. High Performance Green Propulsion (HPGP), and the associated propellant technology, has advanced significantly in maturity with increased familiarity with LMP-103S propellant handling, the proven reduction in loading hazards, successful launches conducted at multiple international Ranges, and HPGP on-orbit flight heritage. As science missions move forward to the potential infusion of HPGP technology, the National Aeronautics and Space Administration (NASA) and its partners are working to address gaps in system performance and operational considerations.
NASA Astrophysics Data System (ADS)
Darius, D.; Misaran, M. S.; Rahman, Md. M.; Ismail, M. A.; Amaludin, A.
2017-07-01
The study on the effect of the working parameters such as pipe material, pipe length, pipe diameter, depth of burial of the pipe, air flow rate and different types of soils on the thermal performance of earth-air heat exchanger (EAHE) systems is very crucial to ensure that thermal comfort can be achieved. In the past decade, researchers have performed studies to develop numerical models for analysis of EAHE systems. Until recently, two-dimensional models replaced the numerical models in the 1990s and in recent times, more advanced analysis using three-dimensional models, specifically the Computational Fluid Dynamics (CFD) simulation in the analysis of EAHE system. This paper reviews previous models used to analyse the EAHE system and working parameters that affects the earth-air heat exchanger (EAHE) thermal performance as of February 2017. Recent findings on the parameters affecting EAHE performance are also presented and discussed. As a conclusion, with the advent of CFD methods, investigational work have geared up to modelling and simulation work as it saves time and cost. Comprehension of the EAHE working parameters and its effect on system performance is largely established. However, the study on type of soil and its characteristics on the performance of EAHEs systems are surprisingly barren. Therefore, future studies should focus on the effect of soil characteristics such as moisture content, density of soil, and type of soil on the thermal performance of EAHEs system.
Intelligent Work Process Engineering System
NASA Technical Reports Server (NTRS)
Williams, Kent E.
2003-01-01
Optimizing performance on work activities and processes requires metrics of performance for management to monitor and analyze in order to support further improvements in efficiency, effectiveness, safety, reliability and cost. Information systems are therefore required to assist management in making timely, informed decisions regarding these work processes and activities. Currently information systems regarding Space Shuttle maintenance and servicing do not exist to make such timely decisions. The work to be presented details a system which incorporates various automated and intelligent processes and analysis tools to capture organize and analyze work process related data, to make the necessary decisions to meet KSC organizational goals. The advantages and disadvantages of design alternatives to the development of such a system will be discussed including technologies, which would need to bedesigned, prototyped and evaluated.
Komori, Mie
2016-01-01
Monitoring is an executive function of working memory that serves to update novel information, focusing attention on task-relevant targets, and eliminating task-irrelevant noise. The present research used a verbal working memory task to examine how working memory capacity limits affect monitoring. Participants performed a Japanese listening span test that included maintenance of target words and listening comprehension. On each trial, participants responded to the target word and then immediately estimated confidence in recall performance for that word (metacognitive judgment). The results confirmed significant differences in monitoring accuracy between high and low capacity groups in a multi-task situation. That is, confidence judgments were superior in high vs. low capacity participants in terms of absolute accuracy and discrimination. The present research further investigated how memory load and interference affect underestimation of successful recall. The results indicated that the level of memory load that reduced word recall performance and led to an underconfidence bias varied according to participants' memory capacity. In addition, irrelevant information associated with incorrect true/ false decisions (secondary task) and word recall within the current trial impaired monitoring accuracy in both participant groups. These findings suggest that interference from unsuccessful decisions only influences low, but not high, capacity participants. Therefore, monitoring accuracy, which requires high working memory capacity, improves metacognitive abilities by inhibiting task-irrelevant noise and focusing attention on detecting task-relevant targets or useful retrieval cues, which could improve actual cognitive performance.
Math anxiety differentially affects WAIS-IV arithmetic performance in undergraduates.
Buelow, Melissa T; Frakey, Laura L
2013-06-01
Previous research has shown that math anxiety can influence the math performance level; however, to date, it is unknown whether math anxiety influences performance on working memory tasks during neuropsychological evaluation. In the present study, 172 undergraduate students completed measures of math achievement (the Math Computation subtest from the Wide Range Achievement Test-IV), math anxiety (the Math Anxiety Rating Scale-Revised), general test anxiety (from the Adult Manifest Anxiety Scale-College version), and the three Working Memory Index tasks from the Wechsler Adult Intelligence Scale-IV Edition (WAIS-IV; Digit Span [DS], Arithmetic, Letter-Number Sequencing [LNS]). Results indicated that math anxiety predicted performance on Arithmetic, but not DS or LNS, above and beyond the effects of gender, general test anxiety, and math performance level. Our findings suggest that math anxiety can negatively influence WAIS-IV working memory subtest scores. Implications for clinical practice include the utilization of LNS in individuals expressing high math anxiety.
Characterizing Detonating LX-17 Charges Crossing a Transverse Air Gap with Experiments and Modeling
NASA Astrophysics Data System (ADS)
Lauderbach, Lisa M.; Souers, P. Clark; Garcia, Frank; Vitello, Peter; Vandersall, Kevin S.
2009-12-01
Experiments were performed using detonating LX-17 (92.5% TATB, 7.5% Kel-F by weight) charges with various width transverse air gaps with manganin peizoresistive in-situ gauges present. The experiments, performed with 25 mm diameter by 25 mm long LX-17 pellets with the transverse air gap in between, showed that transverse gaps up to about 3 mm could be present without causing the detonation wave to fail to continue as a detonation. The Tarantula/JWL++ code was utilized to model the results and compare with the in-situ gauge records with some agreement to the experimental data with additional work needed for a better match to the data. This work will present the experimental details as well as comparison to the model results.
Leavitt, Victoria M; Lengenfelder, Jean; Moore, Nancy B; Chiaravalloti, Nancy D; DeLuca, John
2011-06-01
Cognitive symptoms of multiple sclerosis (MS) include processing-speed deficits and working memory impairment. The precise manner in which these deficits interact in individuals with MS remains to be explicated. We hypothesized that providing more time on a complex working memory task would result in performance benefits for individuals with MS relative to healthy controls. Fifty-three individuals with clinically definite MS and 36 matched healthy controls performed a computerized task that systematically manipulated cognitive load. The interval between stimuli presentations was manipulated to provide increasing processing time. The results confirmed that individuals with MS who have processing-speed deficits significantly improve in performance accuracy when given additional time to process the information in working memory. Implications of these findings for developing appropriate cognitive rehabilitation interventions are discussed.
Effect of overtime work on cognitive function in automotive workers.
Proctor, S P; White, R F; Robins, T G; Echeverria, D; Rocskay, A Z
1996-04-01
The present investigation examined whether increased overtime work predicts impairment in cognitive performance in the domains of attention, executive function, and mood. The behavioral and cognitive functions of 248 automotive workers were measured by a neurobehavioral test performance. Overtime, defined as number of hours worked greater than 8 h a day or greater than 5 d a week, was calculated from company payroll records for the week before the test day. The number of consecutive days worked before the test day was also determined. Cross-sectional data analysis by multiple linear regression, after adjustment for the effects of age, education, gender, alcohol intake, repeated grade in school, acute petroleum naphtha exposure, shift worked, job type, number of consecutive days worked before the test day, and number of hours worked on the test day before the testing, demonstrated that increased overtime was significantly associated with impaired performance on several tests of attention and executive function. Increased feelings of depression, fatigue, and confusion were also associated with increased overtime work. In addition significant interaction effects were observed for job type but not for naphtha exposure. The findings support the hypothesis that overtime work results in impaired cognitive performance in the areas of attention and executive function and that both overtime hours and the number of consecutive days worked prior to a test day affect mood.
Gilbert, Nicky
2009-02-01
The importance of nutrition in sport has been recognised since the ancient Olympians, and its role in improving both health and sports performance has widespread acceptance. However, in sporting circles nutritional knowledge, beliefs and practices are extremely varied. Within any sporting organisation the sports dietitian or nutritionist must be able to work with athletes, their family, coaches and other support staff to develop and monitor realistic and practical strategies that work best for each performer, contributing to a positive and sustained outcome on performance. The present review examines the practical application of current key issues in performance nutrition, highlighting the advantages of early intervention in youth development and comprehensive and integrated nutrition services.
A study of emissions from passenger cars in six cities. Volume B. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-01-01
This is the second of two volumes presenting results from a series of exhaust emission and fuel economy tests performed on a representative sample of vehicles in six U.S. cities. Data presented in the following sections are generated in appendix form as part of a contract with the EPA to perform work for the FY 77 Passenger Car Emission Factor Program. Volume B includes the balance of individual vehicle data derived from the Two Speed Idle and Federal Three Mode tests. It also includes the results of Vehicle Driveability Evaluations, Maladjustment and Disablement Inspections, tire inspections and a listing ofmore » comparative mileage data. Information presented in Volume B should not be interpreted without the benefit of additional descriptive data presented in Volume A as both volumes comprise the results of a single work effort and are not intended to be considered separately.« less
Analysis of Trinity Power Metrics for Automated Monitoring
DOE Office of Scientific and Technical Information (OSTI.GOV)
Michalenko, Ashley Christine
This is a presentation from Los Alamos National Laboraotyr (LANL) about the analysis of trinity power metrics for automated monitoring. The following topics are covered: current monitoring efforts, motivation for analysis, tools used, the methodology, work performed during the summer, and future work planned.
Belopolsky, Artem V; Theeuwes, Jan
2009-10-01
The present study systematically examined the role of attention in maintenance of spatial representations in working memory as proposed by the attention-based rehearsal hypothesis [Awh, E., Jonides, J., & Reuter-Lorenz, P. A. (1998). Rehearsal in spatial working memory. Journal of Experimental Psychology--Human Perception and Performance, 24(3), 780-790]. Three main issues were examined. First, Experiments 1-3 demonstrated that inhibition and not facilitation of visual processing is often observed at the memorized location during the retention interval. This inhibition was caused by keeping a location in memory and not by the exogenous nature of the memory cue. Second, Experiment 4 showed that inhibition of the memorized location does not lead to any significant impairment in memory accuracy. Finally, Experiment 5 connected current results to the previous findings and demonstrated facilitation of processing at the memorized location. Importantly, facilitation of processing did not lead to more accurate memory performance. The present results challenge the functional role of attention in maintenance of spatial working memory representations.
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.
NASA Astrophysics Data System (ADS)
Bird, Robert; Nystrom, David; Albright, Brian
2017-10-01
The ability of scientific simulations to effectively deliver performant computation is increasingly being challenged by successive generations of high-performance computing architectures. Code development to support efficient computation on these modern architectures is both expensive, and highly complex; if it is approached without due care, it may also not be directly transferable between subsequent hardware generations. Previous works have discussed techniques to support the process of adapting a legacy code for modern hardware generations, but despite the breakthroughs in the areas of mini-app development, portable-performance, and cache oblivious algorithms the problem still remains largely unsolved. In this work we demonstrate how a focus on platform agnostic modern code-development can be applied to Particle-in-Cell (PIC) simulations to facilitate effective scientific delivery. This work builds directly on our previous work optimizing VPIC, in which we replaced intrinsic based vectorisation with compile generated auto-vectorization to improve the performance and portability of VPIC. In this work we present the use of a specialized SIMD queue for processing some particle operations, and also preview a GPU capable OpenMP variant of VPIC. Finally we include a lessons learnt. Work performed under the auspices of the U.S. Dept. of Energy by the Los Alamos National Security, LLC Los Alamos National Laboratory under contract DE-AC52-06NA25396 and supported by the LANL LDRD program.
The development of visuo-spatial working memory.
Pickering, S J
2001-01-01
Children's performance on tests of visuo-spatial working memory improves with age, although relatively little is known about why this happens. One explanation concerns the development of the ability to recode visually presented information into phonological form. This process appears to be used from around 8 years of age and is a major contributor to tasks in which stimuli can be verbally labelled. However, evidence suggests that phonological recoding cannot account for all of the age-related change in performance on visuo-spatial working memory tasks. In this review, four other mechanisms (knowledge, processing strategies, processing speed, and attentional capacity) are considered in terms of their contribution to children's visuo-spatial working memory development.
Work Measurement as a Generalized Quantum Measurement
NASA Astrophysics Data System (ADS)
Roncaglia, Augusto J.; Cerisola, Federico; Paz, Juan Pablo
2014-12-01
We present a new method to measure the work w performed on a driven quantum system and to sample its probability distribution P (w ). The method is based on a simple fact that remained unnoticed until now: Work on a quantum system can be measured by performing a generalized quantum measurement at a single time. Such measurement, which technically speaking is denoted as a positive operator valued measure reduces to an ordinary projective measurement on an enlarged system. This observation not only demystifies work measurement but also suggests a new quantum algorithm to efficiently sample the distribution P (w ). This can be used, in combination with fluctuation theorems, to estimate free energies of quantum states on a quantum computer.
Full Geant4 and FLUKA simulations of an e-LINAC for its use in particle detectors performance tests
NASA Astrophysics Data System (ADS)
Alpat, B.; Pilicer, E.; Servoli, L.; Menichelli, M.; Tucceri, P.; Italiani, M.; Buono, E.; Di Capua, F.
2012-03-01
In this work we present the results of full Geant4 and FLUKA simulations and comparison with dosimetry data of an electron LINAC of St. Maria Hospital located in Terni, Italy. The facility is being used primarily for radiotherapy and the goal of the present study is the detailed investigation of electron beam parameters to evaluate the possibility to use the e-LINAC (during time slots when it is not used for radiotherapy) to test the performance of detector systems, in particular those designed to operate in space. The critical beam parameters are electron energy, profile and flux available at the surface of device to be tested. The present work aims to extract these parameters from dosimetry calibration data available at the e-LINAC. The electron energy ranges from 4 MeV to 20 MeV. The dose measurements have been performed by using an Advanced Markus Chamber which has a small sensitive volume.
NASA Astrophysics Data System (ADS)
Bennett, Ian Graham
Automatic Dependent Surveillance-Broadcast (ADS-B) is quickly becoming the new standard for more efficient air traffic control, but as a satellite/ground-based hybrid system it faces limitations on its usefulness over oceans and remote areas. Tracking of aircraft from space presents many challenges that if overcome will greatly increase the safety and efficiency of commercial air travel in these areas. This thesis presents work performed to develop a flight-ready ADS-B receiver payload for the CanX-7 technology demonstration satellite. Work presented includes a simulation of payload performance and coverage area, the design and testing of a single-feed circularly polarized L-band antenna, the design of software to control the payload and manage its data, and verification of the performance of the hardware prior to integration with the satellite and launch. Also included is a short overview of results from the seven-month aircraft tracking campaign conducted with the spacecraft.
Event-related potentials elicited during working memory are altered in mild cognitive impairment.
López Zunini, Rocío A; Knoefel, Frank; Lord, Courtney; Dzuali, Fiatsogbe; Breau, Michael; Sweet, Lisa; Goubran, Rafik; Taler, Vanessa
2016-11-01
Persons with Mild Cognitive Impairment (MCI) can experience deficits in working memory. In the present study, we investigated working memory in persons with MCI and cognitively healthy older adults using event-related potentials (ERPs). Participants performed an n-back working memory task with baseline (0-back), low load (1-back), and high load (2-back) working memory conditions. MCI participants' performance was less accurate than that of healthy older adults in both the 1-back and 2-back conditions, and reaction times were longer in MCI than control participants in the 0-back, 1-back and 2-back conditions. ERP analyses revealed delayed P200 and N200 latencies and smaller P300 amplitudes in MCI relative to control participants in the 0-back, 1-back and 2-back conditions. Deterioration in working memory performance concomitant with marked electrophysiological alterations suggests that persons with MCI exhibit deficits in several cognitive processes that include early attention, stimulus discrimination and classification, and updating and manipulation of information held in working memory. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Marchukov, E.; Egorov, I.; Popov, G.; Baturin, O.; Goriachkin, E.; Novikova, Y.; Kolmakova, D.
2017-08-01
The article presents one optimization method for improving of the working process of an axial compressor of gas turbine engine. Developed method allows to perform search for the best geometry of compressor blades automatically by using optimization software IOSO and CFD software NUMECA Fine/Turbo. Optimization was performed by changing the form of the middle line in the three sections of each blade and shifts of three sections of the guide vanes in the circumferential and axial directions. The calculation of the compressor parameters was performed for work and stall point of its performance map on each optimization step. Study was carried out for seven-stage high-pressure compressor and three-stage low-pressure compressors. As a result of optimization, improvement of efficiency was achieved for all investigated compressors.
Age Differences in Visual Working Memory Capacity: Not Based on Encoding Limitations
ERIC Educational Resources Information Center
Cowan, Nelson; AuBuchon, Angela M.; Gilchrist, Amanda L.; Ricker, Timothy J.; Saults, J. Scott
2011-01-01
Why does visual working memory performance increase with age in childhood? One recent study (Cowan et al., 2010b) ruled out the possibility that the basic cause is a tendency in young children to clutter working memory with less-relevant items (within a concurrent array, colored items presented in one of two shapes). The age differences in memory…
2012 Take Our Children to Work Day
2012-07-31
More than 250 children of employees at 15 Stennis Space Center resident agencies and organizations visited the facility July 31 to participate in annual Take Our Children to Work Day activities. Participants enjoyed various presentations and demonstrations on topics such as cryogenics and information security. They also had an opportunity to visit site facilities to learn about various work performed at the NASA center.
Academic Performance, School Desertion and Emotional Paradigm in University Students
ERIC Educational Resources Information Center
Sosa, Emma Rosa Cruz; Barrientos, Laura Gática; Castro, Patricia Eugenia García; García, Jesús Hernández
2010-01-01
The present work aims to describe academic performance, school desertion and the emotional paradigm of the university students of the accounting school of the Benemérita Universidad Autónoma de Puebla (FCPBUAP). We have found that low academic performance is related to students' economic deficiency, which affects their concentration on their…
ERIC Educational Resources Information Center
Brannick, Michael T., Ed.; Salas, Eduardo, Ed.; Prince, Carolyn, Ed.
This volume presents thoughts on measuring team performance written by experts currently working with teams in fields such as training, evaluation, and process consultation. The chapters are: (1) "An Overview of Team Performance Measurement" (Michael T. Brannick and Carolyn Prince); (2) "A Conceptual Framework for Teamwork Measurement" (Terry L.…
In the Mind's Eye: Enhancing Human Performance.
ERIC Educational Resources Information Center
Druckman, Daniel, Ed.; Bjork, Robert A., Ed.
This book presents a look at methods of performance enhancement, examining basic issues of performance through a series of papers which evaluate several popular self-improvement approaches by weighing the evidence to determine what works. The first of the book's four parts provides an overview of the volume with two chapters describing the history…
Mélan, Claudine; Cascino, Nadine
2014-01-01
The present contribution presents two field studies combining tools and methods from cognitive psychology and from occupational psychology in order to perform a thorough investigation of workload in employees. Cognitive load theory proposes to distinguish different load categories of working memory, in a context of instruction. Intrinsic load is inherent to the task, extraneous load refers to components of a learning environment that may be modified to reduce total load, and germane load enables schemas construction and thus efficient learning. We showed previously that this theoretical framework may be successfully extended to working memory tasks in non-instructional designs. Other theoretical models, issued from the field of occupational psychology, account for an individual's perception of work demands or requirements in the context of different psychosocial features of the (work) environment. Combining these approaches is difficult as workload assessment by job-perception questionnaires explore an individual's overall job-perception over a large time-period, whereas cognitive load investigations in working memory tasks are typically performed within short time-periods. We proposed an original methodology enabling investigation of workload and load factors in a comparable time-frame. We report two field studies investigating workload on different shift-phases and between work-shifts, with two custom-made tools. The first one enabled workload assessment by manipulating intrinsic load (task difficulty) and extraneous load (time pressure) in a working-memory task. The second tool was a questionnaire based on the theoretical concepts of work-demands, control, and psychosocial support. Two additional dimensions suspected to contribute to job-perception, i.e., work-family conflicts and availability of human and technical resources were also explored. Results of workload assessments were discussed in light of operators' alertness and job-performance.
Aerosol Data Assimilation at GMAO
NASA Technical Reports Server (NTRS)
da Silva, Arlindo M.; Buchard, Virginie
2017-01-01
This presentation presents an overview of the aerosol data assimilation work performed at GMAO. The GMAO Forward Processing system and the biomass burning emissions from QFED are first presented. Then, the current assimilation of Aerosol Optical Depth (AOD), performed by means of the analysis splitting method is briefly described, followed by some results on the quality control of observations using a Neural Network trained using AERONET AOD. Some applications are shown such as the Mount Pinatubo eruption in 1991 using the MERRA-2 aerosol dataset. Finally preliminary results on the EnKF implementation for aerosol assimilation are presented.
Attention and working memory in elderly: the influence of a distracting environment.
Rodrigues, Pedro F S; Pandeirada, Josefa N S
2015-02-01
The present work investigated the effect of a distracting environment in the performance of attentional and working memory (WM) tasks in elderly participants. To this end, forty elderly performed two attentional tasks (simple reaction time and go/no-go tasks), and three WM tasks (arithmetic, memory for digits and sequences of letters and numbers). Each participant performed the tasks in a distracting and a non-distracting environment, with an interval of 14-21 days between sessions. The results revealed better performance in the attentional tasks when these were done in the non-distracting environment, as compared to when they were done in the distracting environment. Specifically, participants provided more accurate responses, fewer false alarms and omissions when responding in the non-distracting environment than when responding in the distracting environment. Participants were also faster at providing correct responses in the go/no-go task when it was performed in the non-distracting environment. As for the memory tasks, the effect of type of environment was significant only in the memory for digits in a forward direction task. Our data suggest the need to consider the potential damaging consequences of distracting environments when the elderly have to perform tasks that demand their attention. Specific examples of such situations are presented in the discussion (e.g., distracting effect of environment on medical and on psychological evaluations).
Employer attitudes towards the work inclusion of people with disability.
Nota, Laura; Santilli, Sara; Ginevra, Maria C; Soresi, Salvatore
2014-11-01
This study examines the importance of work in life of people with disability and then focuses on employer attitudes towards these people. In the light of Stone and Colella's model, the study examines the employer attitudes and the role of variables such as type of disability, employer experience in the hiring of persons with disabilities, the description of hypothetical hirees with disabilities, the ways in which employers evaluate work performance and social acceptability, and the work tasks that they consider appropriate for workers with disability. Eighty employers were randomly assigned to standard condition (candidates with disability were presented by referring to the disability they presented) or positive condition (candidates were presented with reference to their strengths). It was found that the type of disability and its presentation influence employer attitudes. In addition, realistic and conventional tasks were considered appropriate for hirees with disabilities. Implications were discussed. © 2013 John Wiley & Sons Ltd.
Neuroimaging correlates of parent ratings of working memory in typically developing children
Mahone, E. Mark; Martin, Rebecca; Kates, Wendy R.; Hay, Trisha; Horská, Alena
2009-01-01
The purpose of the present study was to investigate construct validity of parent ratings of working memory in children, using a multi-trait/multi-method design including neuroimaging, rating scales, and performance-based measures. Thirty-five typically developing children completed performance-based tests of working memory and nonexecutive function (EF) skills, received volumetric MRI, and were rated by parents on both EF-specific and broad behavior rating scales. After controlling for total cerebral volume and age, parent ratings of working memory were significantly correlated with frontal gray, but not temporal, parietal, or occipital gray, or any lobar white matter volumes. Performance-based measures of working memory were also moderately correlated with frontal lobe gray matter volume; however, non-EF parent ratings and non-EF performance-based measures were not correlated with frontal lobe volumes. Results provide preliminary support for the convergent and discriminant validity of parent ratings of working memory, and emphasize their utility in exploring brain–behavior relationships in children. Rating scales that directly examine EF skills may potentially have ecological validity, not only for “everyday” function, but also as correlates of brain volume. PMID:19128526
Entringer, Sonja; Buss, Claudia; Kumsta, Robert; Hellhammer, Dirk H; Wadhwa, Pathik D; Wüst, Stefan
2009-08-01
The aim of the present study was to examine the association between prenatal psychosocial stress exposure and subsequent prefrontal cortex-dependent working memory performance in human adults. Working memory performance was assessed using an item-recognition task under 10 mg hydrocortisone (cortisol) and placebo conditions in a sample of 32 healthy young women (mean age = 25 +/- 4.34 years) whose mothers experienced a major negative life event during their pregnancy (Prenatal Stress, PS group), and in a comparison group of 27 healthy young women (mean age = 24 +/- 3.4 years). The two groups did not differ in the placebo condition, however, subjects in the PS group showed longer reaction times after hydrocortisone administration compared with subjects in the comparison group (p = .02). These findings provide support for an association between prenatal stress exposure and the potential modulatory effect of cortisol on working memory performance in young adults, which may reflect compromised development of the prefrontal cortex in prenatal life. 2009 APA, all rights reserved
Baumann, Oliver; Skilleter, Ashley J.; Mattingley, Jason B.
2011-01-01
The goal of the present study was to examine the extent to which working memory supports the maintenance of object locations during active spatial navigation. Participants were required to navigate a virtual environment and to encode the location of a target object. In the subsequent maintenance period they performed one of three secondary tasks that were designed to selectively load visual, verbal or spatial working memory subsystems. Thereafter participants re-entered the environment and navigated back to the remembered location of the target. We found that while navigation performance in participants with high navigational ability was impaired only by the spatial secondary task, navigation performance in participants with poor navigational ability was impaired equally by spatial and verbal secondary tasks. The visual secondary task had no effect on navigation performance. Our results extend current knowledge by showing that the differential engagement of working memory subsystems is determined by navigational ability. PMID:21629686
Functional neuroanatomical associations of working memory in early-onset Alzheimer's disease.
Kobylecki, Christopher; Haense, Cathleen; Harris, Jennifer M; Stopford, Cheryl L; Segobin, Shailendra H; Jones, Matthew; Richardson, Anna M T; Gerhard, Alexander; Anton-Rodriguez, José; Thompson, Jennifer C; Herholz, Karl; Snowden, Julie S
2018-01-01
To characterize metabolic correlates of working memory impairment in clinically defined subtypes of early-onset Alzheimer's disease. Established models of working memory suggest a key role for frontal lobe function, yet the association in Alzheimer's disease between working memory impairment and visuospatial and language symptoms suggests that temporoparietal neocortical dysfunction may be responsible. Twenty-four patients with predominantly early-onset Alzheimer's disease were clinically classified into groups with predominantly amnestic, multidomain or visual deficits. Patients underwent neuropsychological evaluation focused on the domains of episodic and working memory, T1-weighted magnetic resonance imaging and brain fluorodeoxyglucose positron emission tomography. Fluorodeoxyglucose positron emission tomography data were analysed by using a region-of-interest approach. Patients with multidomain and visual presentations performed more poorly on tests of working memory compared with amnestic Alzheimer's disease. Working memory performance correlated with glucose metabolism in left-sided temporoparietal, but not frontal neocortex. Carriers of the apolipoprotein E4 gene showed poorer episodic memory and better working memory performance compared with noncarriers. Our findings support the hypothesis that working memory changes in early-onset Alzheimer's disease are related to temporoparietal rather than frontal hypometabolism and show dissociation from episodic memory performance. They further support the concept of subtypes of Alzheimer's disease with distinct cognitive profiles due to prominent neocortical dysfunction early in the disease course. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Oetjen, Sophie; Ziefle, Martina
2009-01-01
An increasing demand to work with electronic displays and to use mobile computers emphasises the need to compare visual performance while working with different screen types. In the present study, a cathode ray tube (CRT) was compared to an external liquid crystal display (LCD) and a Notebook-LCD. The influence of screen type and viewing angle on discrimination performance was studied. Physical measurements revealed that luminance and contrast values change with varying viewing angles (anisotropy). This is most pronounced in Notebook-LCDs, followed by external LCDs and CRTs. Performance data showed that LCD's anisotropy has negative impacts on completing time critical visual tasks. The best results were achieved when a CRT was used. The largest deterioration of performance resulted when participants worked with a Notebook-LCD. When it is necessary to react quickly and accurately, LCD screens have disadvantages. The anisotropy of LCD-TFTs is therefore considered to be as a limiting factor deteriorating visual performance.
29 CFR 1918.92 - Illumination.
Code of Federal Regulations, 2011 CFR
2011-07-01
... operations, illumination for cargo transfer operations shall be of a minimum light intensity of five foot-candles (54 lux). Where work tasks require more light to be performed safely, supplemental lighting shall... surface, in the plane in which the task/working surface is present. (c) Arrangement of lights. Lights...
Working memory can enhance unconscious visual perception.
Pan, Yi; Cheng, Qiu-Ping; Luo, Qian-Ying
2012-06-01
We demonstrate that unconscious processing of a stimulus property can be enhanced when there is a match between the contents of working memory and the stimulus presented in the visual field. Participants first held a cue (a colored circle) in working memory and then searched for a brief masked target shape presented simultaneously with a distractor shape. When participants reported having no awareness of the target shape at all, search performance was more accurate in the valid condition, where the target matched the cue in color, than in the neutral condition, where the target mismatched the cue. This effect cannot be attributed to bottom-up perceptual priming from the presentation of a memory cue, because unconscious perception was not enhanced when the cue was merely perceptually identified but not actively held in working memory. These findings suggest that reentrant feedback from the contents of working memory modulates unconscious visual perception.
Processing distinct linguistic information types in working memory in aphasia.
Wright, Heather Harris; Downey, Ryan A; Gravier, Michelle; Love, Tracy; Shapiro, Lewis P
2007-06-01
BACKGROUND: Recent investigations have suggested that adults with aphasia present with a working memory deficit that may contribute to their language-processing difficulties. Working memory capacity has been conceptualised as a single "resource" pool for attentional, linguistic, and other executive processing-alternatively, it has been suggested that there may be separate working memory abilities for different types of linguistic information. A challenge in this line of research is developing an appropriate measure of working memory ability in adults with aphasia. One candidate measure of working memory ability that may be appropriate for this population is the n-back task. By manipulating stimulus type, the n-back task may be appropriate for tapping linguistic-specific working memory abilities. AIMS: The purposes of this study were (a) to measure working memory ability in adults with aphasia for processing specific types of linguistic information, and (b) to examine whether a relationship exists between participants' performance on working memory and auditory comprehension measures. METHOD #ENTITYSTARTX00026; PROCEDURES: Nine adults with aphasia participated in the study. Participants completed three n-back tasks, each tapping different types of linguistic information. They included the PhonoBack (phonological level), SemBack (semantic level), and SynBack (syntactic level). For all tasks, two n-back levels were administered: a 1-back and 2-back. Each level contained 20 target items; accuracy was recorded by stimulus presentation software. The Subject-relative, Object-relative, Active, Passive Test of Syntactic Complexity (SOAP) was the syntactic sentence comprehension task administered to all participants. OUTCOMES #ENTITYSTARTX00026; RESULTS: Participants' performance declined as n-back task difficulty increased. Overall, participants performed better on the SemBack than PhonoBack and SynBack tasks, but the differences were not statistically significant. Finally, participants who performed poorly on the SynBack also had more difficulty comprehending syntactically complex sentence structures (i.e., passive & object-relative sentences). CONCLUSIONS: Results indicate that working memory ability for different types of linguistic information can be measured in adults with aphasia. Further, our results add to the growing literature that favours separate working memory abilities for different types of linguistic information view.
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
The Electrical Engineering Profession at NASA
NASA Technical Reports Server (NTRS)
Emerson, Dawn
2004-01-01
Presentation given at the opening ceremony of the Centre of Vocational Excellence in Birmingham, England on October 7, 2004. Presentation highlights examples of work performed by Electrical Engineers at the NASA Glenn Research Center and highlights the demographics of the NASA workforce. Presentation is intended to be inspirational in nature.
Telerobotics for Human Exploration: Enhancing Crew Capabilities in Deep Space
NASA Technical Reports Server (NTRS)
Fong, Terrence
2013-01-01
Future space missions in Earth orbit, to the Moon, and to other distant destinations offer many new opportunities for exploration. But, astronaut time will always be limited and some work will not be feasible or efficient for humans to perform manually. Telerobots, however, can complement human explorers, performing work under remote control from Earth, orbit or nearby habitats. A central challenge, therefore, is to understand how humans and remotely operated robots can be jointly employed to maximize mission performance and success. This presentation provides an overview of the key issues with using telerobots for human exploration.
NASA Astrophysics Data System (ADS)
Berzak Hopkins, L.; Divol, L.; Lepape, S.; Meezan, N. B.; Dewald, E.; Ho, D.; Khan, S.; Pak, A.; Ralph, J.; Ross, J. S.
2016-10-01
Recent simulation-based and experimental work using high-density carbon ablators in unlined uranium hohlraums with 0.3 mg/cc helium fill have demonstrated round implosions with minimal evolution of Legendre moment P2 during burn. To extend this promising work, design studies have been performed to explore potential performance improvements with larger capsules, while maintaining similar case-to-capsule target ratios. We present here the results of these design studies, which will motivate a series of upcoming experiments at the National Ignition Facility. Prepared by LLNL under Contract DE-AC52-07NA27344.
Increase of Gas-Turbine Plant Efficiency by Optimizing Operation of Compressors
NASA Astrophysics Data System (ADS)
Matveev, V.; Goriachkin, E.; Volkov, A.
2018-01-01
The article presents optimization method for improving of the working process of axial compressors of gas turbine engines. Developed method allows to perform search for the best geometry of compressor blades automatically by using optimization software IOSO and CFD software NUMECA Fine/Turbo. The calculation of the compressor parameters was performed for work and stall point of its performance map on each optimization step. Study was carried out for seven-stage high-pressure compressor and three-stage low-pressure compressors. As a result of optimization, improvement of efficiency was achieved for all investigated compressors.
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.
[Quality of work life in nursing staff].
Zavala, María Olga Quintana; Klijn, Tatiana Maria Paravic
2014-01-01
This article deals with aspects that are related to work, quality of life, and its relationship with the nursing staff within the Mexican context. Professionals in health areas present alterations that are commonly overlooked and barely dealt with, especially when the person is a woman and, the care they give to patients, families, and/or friends, or community members, precede their own self care. In the case of institutions or work areas, even when the job provides human beings with several benefits, it usually lacks the proper conditions to perform the job, carries negatives aspects or pathological conditions, all which can relate to poor levels of Quality of Life at Work. Members of the nursing team need to perform their work in the best possible conditions in order to maintain their physical and mental health.
Supporting clinician educators to achieve "work-work balance".
Maniate, Jerry; Dath, Deepak; Cooke, Lara; Leslie, Karen; Snell, Linda; Busari, Jamiu
2016-10-01
Clinician Educators (CE) have numerous responsibilities in different professional domains, including clinical, education, research, and administration. Many CEs face tensions trying to manage these often competing professional responsibilities and achieve "work-work balance." Rich discussions of techniques for work-work balance amongst CEs at a medical education conference inspired the authors to gather, analyze, and summarize these techniques to share with others. In this paper we present the CE's "Four Ps"; these are practice points that support both the aspiring and established CE to help improve their performance and productivity as CEs, and allow them to approach work-work balance.
CHARACTERIZING DETONATING LX-17 CHARGES CROSSING A TRANSVERSE AIR GAP WITH EXPERIMENTS AND MODELING
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lauderbach, L M; Souers, P C; Garcia, F
2009-06-26
Experiments were performed using detonating LX-17 (92.5% TATB, 7.5% Kel-F by weight) charges with various width transverse air gaps with manganin peizoresistive in-situ gauges present. The experiments, performed with 25 mm diameter by 25 mm long LX-17 pellets with the transverse air gap in between, showed that transverse gaps up to about 3 mm could be present without causing the detonation wave to fail to continue as a detonation. The Tarantula/JWL{sup ++} code was utilized to model the results and compare with the in-situ gauge records with some agreement to the experimental data with additional work needed for a bettermore » match to the data. This work will present the experimental details as well as comparison to the model results.« less
Sad benefit in face working memory: an emotional bias of melancholic depression.
Linden, Stefanie C; Jackson, Margaret C; Subramanian, Leena; Healy, David; Linden, David E J
2011-12-01
Emotion biases feature prominently in cognitive theories of depression and are a focus of psychological interventions. However, there is presently no stable neurocognitive marker of altered emotion-cognition interactions in depression. One reason may be the heterogeneity of major depressive disorder. Our aim in the present study was to find an emotional bias that differentiates patients with melancholic depression from controls, and patients with melancholic from those with non-melancholic depression. We used a working memory paradigm for emotional faces, where two faces with angry, happy, neutral, sad or fearful expression had to be retained over one second. Twenty patients with melancholic depression, 20 age-, education- and gender-matched control participants and 20 patients with non-melancholic depression participated in the study. We analysed performance on the working memory task using signal detection measures. We found an interaction between group and emotion on working memory performance that was driven by the higher performance for sad faces compared to other categories in the melancholic group. We computed a measure of "sad benefit", which distinguished melancholic and non-melancholic patients with good sensitivity and specificity. However, replication studies and formal discriminant analysis will be needed in order to assess whether emotion bias in working memory may become a useful diagnostic tool to distinguish these two syndromes. Copyright © 2011 Elsevier B.V. All rights reserved.
Acute effects of different light spectra on simulated night-shift work without circadian alignment.
Canazei, Markus; Pohl, Wilfried; Bliem, Harald R; Weiss, Elisabeth M
2017-01-01
Short-wavelength and short-wavelength-enhanced light have a strong impact on night-time working performance, subjective feelings of alertness and circadian physiology. In the present study, we investigated acute effects of white light sources with varied reduced portions of short wavelengths on cognitive and visual performance, mood and cardiac output.Thirty-one healthy subjects were investigated in a balanced cross-over design under three light spectra in a simulated night-shift paradigm without circadian adaptation.Exposure to the light spectrum with the largest attenuation of short wavelengths reduced heart rate and increased vagal cardiac parameters during the night compared to the other two light spectra without deleterious effects on sustained attention, working memory and subjective alertness. In addition, colour discrimination capability was significantly decreased under this light source.To our knowledge, the present study for the first time demonstrates that polychromatic white light with reduced short wavelengths, fulfilling current lighting standards for indoor illumination, may have a positive impact on cardiac physiology of night-shift workers without detrimental consequences for cognitive performance and alertness.
Selection within working memory based on a color retro-cue modulates alpha oscillations.
Poch, Claudia; Capilla, Almudena; Hinojosa, José Antonio; Campo, Pablo
2017-11-01
Working Memory (WM) maintains flexible representations. Retrospective cueing studies indicate that selective attention can be directed to memory representations in WM improving performance. While most of the work has explored the neural substrates of orienting attention based on a spatial retro-cue, behavioral studies show that a feature other than location can also improve WM performance. In the present work we explored the oscillatory underpinnings of orienting attention to a relevant representation held in WM guided by a feature value. We recorded EEG data in a group of 36 healthy human subjects (20 females) performing a WM task in which they had to memorize the orientation of four rectangles of different colors. After a maintenance period, a cue was presented indicating the color of the relevant item. We showed that directing attention to a memory item based on its color resulted in a modulation of posterior alpha activity, which appears as more desynchronization in the contralateral than in the ipsilateral hemisphere. Alpha lateralization is considered a neurophysiological marker of external and internal spatial attention. We propose that current findings support the idea that selection of a memory item based on a non-location feature could be accomplished by a spatial attentional mechanism. Moreover, using a centrally presented color retro-cue allowed us to surpass the confounds inherent to the use of spatial retro-cues, supporting that the observed lateralized alpha results from an endogenous attentional mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Creatini, F.; Di Marco, P.; Filippeschi, S.; Fioriti, D.; Mameli, M.
2015-11-01
In the last decade, the continuous development of electronics has pointed out the need for a change in mind with regard to thermal management. In the present scenario, Pulsating Heat Pipes (PHPs) are novel promising two-phase passive heat transport devices that seem to meet all present and future thermal requirements. Nevertheless, PHPs governing phenomena are quite unique and not completely understood. In particular, single closed loop PHPs manifest several drawbacks, mostly related to the reduction of device thermal performance and reliability, i.e. the occurrence of multiple operational quasi-steady states. The present research work proposes the application of an electric field as a technique to promote the circulation of the working fluid in a preferential direction and stabilize the device operation. The tested single closed loop PHP is made of a copper tube with an inner tube diameter equal to 2.00 mm and filled with pure ethanol (60% filling ratio). The electric field is generated by a couple of wire-shaped electrodes powered with DC voltage up to 20 kV and laid parallel to the longitudinal axis of the glass tube constituting the adiabatic section. Although the electric field intensity in the working fluid region is weakened both by the polarization phenomenon of the working fluid and by the interposition of the glass tube, the experimental results highlight the influence of the electric field on the device thermal performance and encourage the continuation of the research in this direction.
High-power UV-LED degradation: Continuous and cycled working condition influence
NASA Astrophysics Data System (ADS)
Arques-Orobon, F. J.; Nuñez, N.; Vazquez, M.; Segura-Antunez, C.; González-Posadas, V.
2015-09-01
High-power (HP) UV-LEDs can replace UV lamps for real-time fluoro-sensing applications by allowing portable and autonomous systems. However, HP UV-LEDs are not a mature technology, and there are still open issues regarding their performance evolution over time. This paper presents a reliability study of 3 W UV-LEDs, with special focus on LED degradation for two working conditions: continuous and cycled (30 s ON and 30 s OFF). Accelerated life tests are developed to evaluate the influence of temperature and electrical working conditions in high-power LEDs degradation, being the predominant failure mechanism the degradation of the package. An analysis that includes dynamic thermal and optical HP UV-LED measurements has been performed. Static thermal and stress simulation analysis with the finite element method (FEM) identifies the causes of package degradation. Accelerated life test results prove that HP UV-LEDs working in cycled condition have a better performance than those working in continuous condition.
Predictors of Processing-Based Task Performance in Bilingual and Monolingual Children
Buac, Milijana; Gross, Megan; Kaushanskaya, Margarita
2016-01-01
In the present study we examined performance of bilingual Spanish-English-speaking and monolingual English-speaking school-age children on a range of processing-based measures within the framework of Baddeley’s working memory model. The processing-based measures included measures of short-term memory, measures of working memory, and a novel word-learning task. Results revealed that monolinguals outperformed bilinguals on the short-term memory tasks but not the working memory and novel word-learning tasks. Further, children’s vocabulary skills and socioeconomic status (SES) were more predictive of processing-based task performance in the bilingual group than the monolingual group. Together, these findings indicate that processing-based tasks that engage verbal working memory rather than short-term memory may be better-suited for diagnostic purposes with bilingual children. However, even verbal working memory measures are sensitive to bilingual children’s language-specific knowledge and demographic characteristics, and therefore may have limited clinical utility. PMID:27179914
Viester, Laura; Verhagen, Evert A L M; Bongers, Paulien M; van der Beek, Allard J
2015-08-01
The objective of the present study is to investigate the effects of a worksite health promotion intervention on musculoskeletal symptoms, physical functioning, work ability, work-related vitality, work performance, and sickness absence. In a randomized controlled design, 314 construction workers were randomized into an intervention group (n = 162) receiving personal coaching, tailored information, and materials, and a control group (n = 152) receiving usual care. Sickness absence was recorded continuously in company records, and questionnaires were completed before, directly after the 6-month intervention period, and 12 months after baseline measurements. Linear and logistic regression analyses were performed to determine intervention effects. No significant changes at 6 or 12 months of follow-up were observed in musculoskeletal symptoms, physical functioning, work ability, work-related vitality, work performance, and sickness absence as a result of the intervention. This study shows that the intervention was not statistically significantly effective on secondary outcomes. Although the intervention improved physical activity, dietary, and weight-related outcomes, it was not successful in decreasing musculoskeletal symptoms and improving other work-related measures. Presumably, more multifaceted interventions are required to establish significant change in these outcomes.
Green Propulsion Advancement and Infusion
NASA Technical Reports Server (NTRS)
Mulkey, Henry W.; Maynard, Andrew P.; Anflo, Kjell
2018-01-01
All space missions benefit from increased propulsion system performance allowing lower spacecraft launch mass, larger scientific payloads, or extended on-orbit lifetimes. Likewise, propellant candidates that offer significant reduction in personnel hazards and shorter payload processing present a more attractive propulsion subsystem solution. Aiming to reduce risk to potential infusion missions and fully comprehend the alternative propellant performance, the work presented herein represents many years of development and collaborative efforts to successfully align higher performance, low toxicity hydrazine alternatives into NASA Goddard Space Flight Center (GSFC) missions. The High Performance Green Propulsion (HPGP) technology is being considered for Science Mission Directorate (SMD) missions.
Age-related changes in working memory and the ability to ignore distraction.
McNab, Fiona; Zeidman, Peter; Rutledge, Robb B; Smittenaar, Peter; Brown, Harriet R; Adams, Rick A; Dolan, Raymond J
2015-05-19
A weakened ability to effectively resist distraction is a potential basis for reduced working memory capacity (WMC) associated with healthy aging. Exploiting data from 29,631 users of a smartphone game, we show that, as age increases, working memory (WM) performance is compromised more by distractors presented during WM maintenance than distractors presented during encoding. However, with increasing age, the ability to exclude distraction at encoding is a better predictor of WMC in the absence of distraction. A significantly greater contribution of distractor filtering at encoding represents a potential compensation for reduced WMC in older age.
ERIC Educational Resources Information Center
Marill, Thomas; And Others
The aim of the CYCLOPS Project research is the development of techniques for allowing computers to perform visual scene analysis, pre-processing of visual imagery, and perceptual learning. Work on scene analysis and learning has previously been described. The present report deals with research on pre-processing and with further work on scene…
Neural Correlates of Working Memory Performance in Adolescents and Young Adults with Dyslexia
ERIC Educational Resources Information Center
Vasic, Nenad; Lohr, Christina; Steinbrink, Claudia; Martin, Claudia; Wolf, Robert Christian
2008-01-01
Behavioral studies indicate deficits in phonological working memory (WM) and executive functioning in dyslexics. However, little is known about the underlying functional neuroanatomy. In the present study, neural correlates of WM in adolescents and young adults with dyslexia were investigated using event-related functional magnetic resonance…
Enhancing a College's Fund-Raising Ability. ERIC Digest.
ERIC Educational Resources Information Center
Leslie, Larry L.
Suggestions on how to enhance a college's fund-raising abilities are presented. Six sections are as follows: exemplary performers (noting the relationships between amounts raised and strategies employed); what works and what does not work in fund- raising (an institution's public visibility is important, and a poverty strategy is not); whether…
The Work, Perceptions and Professional Development of Teachers
ERIC Educational Resources Information Center
Silva, Ana Maria; Herdeiro, Rosalinda
2014-01-01
This article presents work from an ongoing investigation, where the objective is to understand the impact of recent Portuguese legislation--the Teaching Career Statute and its respective Evaluation of Teacher Performance regulations--on the (re)construction of teacher identity, the teaching career and professional development. From an analysis of…
Modality Specificity and Integration in Working Memory: Insights from Visuospatial Bootstrapping
ERIC Educational Resources Information Center
Allen, Richard J.; Havelka, Jelena; Falcon, Thomas; Evans, Sally; Darling, Stephen
2015-01-01
The question of how meaningful associations between verbal and spatial information might be utilized to facilitate working memory performance is potentially highly instructive for models of memory function. The present study explored how separable processing capacities within specialized domains might each contribute to this, by examining the…
Building a Competency-Based Curriculum in Social Work Education
ERIC Educational Resources Information Center
Bracy, Wanda
2018-01-01
The focus on competency in social work education makes the development of a competency-based curriculum critical. This article describes an approach to curriculum building taking into account the integration, coherency, and integrity of such a curriculum. A presentation of how performance outcomes are fundamental to the relationship between the…
MOOC Learning Experience Design: Issues and Challenges
ERIC Educational Resources Information Center
Fournier, Hélène; Kop, Rita
2015-01-01
This paper will present current work on various frameworks that are aimed at guiding the research, development, and evaluation efforts around Massive Open Online Courses (MOOCs). Initiatives and activities, including current work by the National Research Council (NRC) in the context of Learning and Performance Support Systems and MOOCs, will be…
Seizing Workplace Learning Affordances in High-Pressure Work Environments
ERIC Educational Resources Information Center
Gnaur, Dorina
2010-01-01
Work in call centres is often presented as a form of unskilled labour characterized by routinization, technological surveillance and tight management control aimed at reaching intensive performance targets. Beyond delivering business objectives, this control and efficiency strategy is often held to produce counterproductive effects with regard to…
ERIC Educational Resources Information Center
Bredeson, Paul V.
1996-01-01
Presents findings of a survey examining superintendents' work in curriculum development and instructional leadership. Respondents described their curriculum-development role as primarily grounded in facilitation, support, and delegation of work to others. Superintendents performed four major instructional leadership roles as visionaries,…
Studies on Vapor Adsorption Systems
NASA Technical Reports Server (NTRS)
Shamsundar, N.; Ramotowski, M.
1998-01-01
The project consisted of performing experiments on single and dual bed vapor adsorption systems, thermodynamic cycle optimization, and thermal modeling. The work was described in a technical paper that appeared in conference proceedings and a Master's thesis, which were previously submitted to NASA. The present report describes some additional thermal modeling work done subsequently, and includes listings of computer codes developed during the project. Recommendations for future work are provided.
Mélan, Claudine; Cascino, Nadine
2014-01-01
The present contribution presents two field studies combining tools and methods from cognitive psychology and from occupational psychology in order to perform a thorough investigation of workload in employees. Cognitive load theory proposes to distinguish different load categories of working memory, in a context of instruction. Intrinsic load is inherent to the task, extraneous load refers to components of a learning environment that may be modified to reduce total load, and germane load enables schemas construction and thus efficient learning. We showed previously that this theoretical framework may be successfully extended to working memory tasks in non-instructional designs. Other theoretical models, issued from the field of occupational psychology, account for an individual’s perception of work demands or requirements in the context of different psychosocial features of the (work) environment. Combining these approaches is difficult as workload assessment by job-perception questionnaires explore an individual’s overall job-perception over a large time-period, whereas cognitive load investigations in working memory tasks are typically performed within short time-periods. We proposed an original methodology enabling investigation of workload and load factors in a comparable time-frame. We report two field studies investigating workload on different shift-phases and between work-shifts, with two custom-made tools. The first one enabled workload assessment by manipulating intrinsic load (task difficulty) and extraneous load (time pressure) in a working-memory task. The second tool was a questionnaire based on the theoretical concepts of work-demands, control, and psychosocial support. Two additional dimensions suspected to contribute to job-perception, i.e., work–family conflicts and availability of human and technical resources were also explored. Results of workload assessments were discussed in light of operators’ alertness and job-performance. PMID:25232346
NASA Technical Reports Server (NTRS)
Braunscheidel, Edward P.; Welch, Gerard E.; Skoch, Gary J.; Medic, Gorazd; Sharma, Om P.
2014-01-01
The measured aerodynamic performance of a compact, high work factor, single-stage centrifugal compressor, comprising an impeller, diffuser, 90-bend, and exit guide vane (EGV), is reported. Performance levels are based on steady-state total-pressure and total-temperature rake and angularity-probe data acquired at key machine rating planes during recent testing at NASA Glenn Research Center. Aerodynamic performance at the stage level are reported for operation between 70 to 105 of design corrected speed, with subcomponent (impeller, diffuser, and exitguide-vane) detailed flow field measurements presented and discussed at the 100 design-speed condition. Individual component losses from measurements are compared with pre-test predictions on a limited basis.
A Walk on the Human Performance Side--Part 1
ERIC Educational Resources Information Center
Addison, Roger M.; Haig, Carol
2012-01-01
Using their "license to snoop," performance architects uncover the nuances of how work gets done in an organization. This is the first of a four-part series in which each article will present a different organizational level. Typical performance issues and opportunities for each level will be discussed, and helpful models and tools will be shared.…
Rise time and response measurements on a LiSOCl2 cell
NASA Technical Reports Server (NTRS)
Bastien, Caroline; Lecomte, Eric J.
1992-01-01
Dynamic impedance tests were performed on a 180 Ah LiSOCl2 cell in the frame of a short term work contract awarded by Aerospatiale as part of the Hermes Space Plane development work. These tests consisted of rise time and response measurements. The rise time test was performed to show the ability to deliver 4 KW, in the nominal voltage range (75-115 V), within less than 100 microseconds, and after a period at rest of 13 days. The response measurements test consisted of step response and frequency response tests. The frequency response test was performed to characterize the response of the LiSOCl2 cell to a positive or negative load step of 10 A starting from various currents. The test was performed for various depths of discharge and various temperatures. The test results were used to build a mathematical, electrical model of the LiSOCl2 cell which are also presented. The test description, test results, electrical modelization description, and conclusions are presented.
Working memory involved in predicting future outcomes based on past experiences.
Dretsch, Michael N; Tipples, Jason
2008-02-01
Deficits in working memory have been shown to contribute to poor performance on the Iowa Gambling Task [IGT: Bechara, A., & Martin, E.M. (2004). Impaired decision making related to working memory deficits in individuals with substance addictions. Neuropsychology, 18, 152-162]. Similarly, a secondary memory load task has been shown to impair task performance [Hinson, J., Jameson, T. & Whitney, P. (2002). Somatic markers, working memory, and decision making. Cognitive, Affective, & Behavioural Neuroscience, 2, 341-353]. In the present study, we investigate whether the latter findings were due to increased random responding [Franco-Watkins, A. M., Pashler, H., & Rickard, T. C. (2006). Does working memory load lead to greater impulsivity? Commentary on Hinson, Jameson, and Whitney's (2003). Journal of Experimental Psychology: Learning, Memory & Cognition, 32, 443-447]. Participants were tested under Low Working Memory (LWM; n=18) or High Working Memory (HWM; n=17) conditions while performing the Reversed IGT in which punishment was immediate and reward delayed [Bechara, A., Dolan, S., & Hindes, A. (2002). Decision making and addiction (part II): Myopia for the future or hypersensitivity to reward? Neuropsychologia, 40, 1690-1705]. In support of a role for working memory in emotional decision making, compared to the LWM condition, participants in the HWM condition made significantly greater number of disadvantageous selections than that predicted by chance. Performance by the HWM group could not be fully explained by random responding.
Sandbakk, Øyvind; Ettema, Gertjan; Holmberg, Hans-Christer
2012-08-01
During competitions, elite cross-country skiers produce higher external work rates on uphill than on flat terrain. However, it is not presently known whether this reflects solely higher energy expenditure. Furthermore, the kinematic factors associated with these higher rates of uphill work have not yet been examined. Therefore, in the present investigation the work rate and associated kinematic parameters at similar metabolic rates during roller ski skating on flat and uphill terrains have been compared. Seven elite male skiers performed six 5-min sub-maximal exercise bouts at the same low, moderate and high metabolic rates on 2 and 8% inclines, while roller skiing on a treadmill employing the G3 skating technique. The work rate was calculated as work against gravity and friction, whereas the energetic equivalent of VO(2) was taken as the metabolic rate. Gross efficiency was defined as work rate divided by metabolic rate. Kinematic parameters were analyzed in three dimensions. At the same metabolic rate, the work rate, cycle rate, work per cycle and relative duration of propulsive phases during a cycle of movement were all higher on the 8% than on the 2% incline at all speeds (all P < 0.05). At similar work rates, gross efficiency was greater on the 8% incline (P < 0.05). In conclusion, these elite skiers consistently demonstrated higher work rates on the 8% incline. To achieve the higher work rates on the steeper incline, these elite skiers employed higher cycle rates and performed more work per cycle, in association with a longer relative propulsive phase.
Working memory capacity in generalized social phobia.
Amir, Nader; Bomyea, Jessica
2011-05-01
Research suggests that understanding complex social cues depends on the availability of cognitive resources (e.g., Phillips, Channon, Tunstall, Hedenstrom, & Lyons, 2008). In spite of evidence suggesting that executive control functioning may impact anxiety (e.g., Eysenck, Derakshan, Santos, & Calvo, 2007), relatively few studies have examined working memory in individuals with generalized social phobia. Moreover, few studies have examined the role of threat-relevant content in working memory performance in clinically anxious populations. To this end, the present study assessed working memory capacity (WMC) in individuals with generalized social phobia and nonanxious controls using an operation span task with threat-relevant and neutral stimuli. Results revealed that nonanxious individuals demonstrated better WMC than individuals with generalized social phobia for neutral words but not for social threat words. Individuals with generalized social phobia demonstrated better WMC performance for threat words relative to neutral words. These results suggest that individuals with generalized social phobia may have relatively enhanced working memory performance for salient, socially relevant information. This enhanced working memory capacity for threat-relevant information may be the result of practice with this information in generalized social phobia.
Chronic pain, work performance and litigation.
Blyth, Fiona M; March, Lyn M; Nicholas, Michael K; Cousins, Michael J
2003-05-01
The overall population impact of chronic pain on work performance has been underestimated as it has often been described in terms of work-related absence, excluding more subtle effects that chronic pain may have on the ability to work effectively. Additionally, most studies have focussed on occupational and/or patient cohorts and treatment seeking, rather than sampling from the general population. We undertook a population-based random digit dialling computer-assisted telephone survey with participants randomly selected within households in order to measure the impact of chronic pain on work performance. In addition, we measured the association between pain-related disability and litigation. The study took place in Northern Sydney Health Area, a geographically defined urban area of New South Wales, Australia, and included 484 adults aged 18 or over with chronic pain. The response rate was 73.4%. Working with pain was more common (on an average 83.8 days in 6 months) than lost work days due to pain (4.5 days) among chronic pain participants in full-time or part-time employment. When both lost work days and reduced-effectiveness work days were summed, an average of 16.4 lost work day equivalents occurred in a 6-month period, approximately three times the average number of lost work days. In multiple logistic regression modelling with pain-related disability as the dependent variable, past or present pain-related litigation had the strongest association (odds ratio (OR)=3.59, P=0.001). In conclusion, chronic pain had a larger impact on work performance than has previously been recognised, related to reduced performance while working with pain. A significant proportion were able to work effectively with pain, suggesting that complete relief of pain may not be an essential therapeutic target. Litigation (principally work-related) for chronic pain was strongly associated with higher levels of pain-related disability, even after taking into account other factors associated with poor functional outcomes.
Veling, Harm; Bijleveld, Erik
2015-12-01
Valuable monetary rewards can boost human performance on various effortful tasks even when the value of the rewards is presented too briefly to allow for strategic decision making. However, the mechanism by which briefly-presented reward information influences performance has remained unclear. One possibility is that performance after briefly-presented reward information is primarily boosted via activation of the dopamine reward system, whereas performance after very visible reward information is driven more by strategic processes. To examine this hypothesis, we first presented participants with a task in which they could earn rewards of relatively low (1 cent) or high (10 cents) value, and the value information was presented either briefly (17 ms) or for an extended duration (300 ms). Furthermore, responsiveness of the dopamine system was indirectly estimated with a measure of risk taking, the Balloon Analogue Risk Task (BART). Results showed that performance after high- compared to low-value rewards was indeed related to the BART scores only when reward information was presented briefly. These results are suggestive of the possibility that brief presentation of reward information boosts performance directly via activating the dopamine system, whereas extended presentation of reward information leads to more strategic reward-driven behavior. Copyright © 2015 Elsevier Inc. All rights reserved.
Neurofeedback training improves attention and working memory performance.
Wang, Jinn-Rong; Hsieh, Shulan
2013-12-01
The present study aimed to investigate the effectiveness of the frontal-midline theta (fmθ) activity uptraining protocol on attention and working memory performance of older and younger participants. Thirty-two participants were recruited. Participants within each age group were randomly assigned to either the neurofeedback training (fmθ uptraining) group or the sham-neurofeedback training group. There was a significant improvement in orienting scores in the older neurofeedback training group. In addition, there was a significant improvement in conflict scores in both the older and young neurofeedback training groups. However, alerting scores failed to increase. In addition, the fmθ training was found to improve working memory function in the older participants. The results further showed that fmθ training can modulate resting EEG for both neurofeedback groups. Our study demonstrated that fmθ uptraining improved attention and working memory performance and theta activity in the resting state for normal aging adults. In addition, younger participants also benefited from the present protocol in terms of improving their executive function. The current findings contribute to a better understanding of the mechanisms underlying neurofeedback training in cognitive function, and suggest that the fmθ uptraining protocol is an effective intervention program for cognitive aging. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Development of Flight-Test Performance Estimation Techniques for Small Unmanned Aerial Systems
NASA Astrophysics Data System (ADS)
McCrink, Matthew Henry
This dissertation provides a flight-testing framework for assessing the performance of fixed-wing, small-scale unmanned aerial systems (sUAS) by leveraging sub-system models of components unique to these vehicles. The development of the sub-system models, and their links to broader impacts on sUAS performance, is the key contribution of this work. The sub-system modeling and analysis focuses on the vehicle's propulsion, navigation and guidance, and airframe components. Quantification of the uncertainty in the vehicle's power available and control states is essential for assessing the validity of both the methods and results obtained from flight-tests. Therefore, detailed propulsion and navigation system analyses are presented to validate the flight testing methodology. Propulsion system analysis required the development of an analytic model of the propeller in order to predict the power available over a range of flight conditions. The model is based on the blade element momentum (BEM) method. Additional corrections are added to the basic model in order to capture the Reynolds-dependent scale effects unique to sUAS. The model was experimentally validated using a ground based testing apparatus. The BEM predictions and experimental analysis allow for a parameterized model relating the electrical power, measurable during flight, to the power available required for vehicle performance analysis. Navigation system details are presented with a specific focus on the sensors used for state estimation, and the resulting uncertainty in vehicle state. Uncertainty quantification is provided by detailed calibration techniques validated using quasi-static and hardware-in-the-loop (HIL) ground based testing. The HIL methods introduced use a soft real-time flight simulator to provide inertial quality data for assessing overall system performance. Using this tool, the uncertainty in vehicle state estimation based on a range of sensors, and vehicle operational environments is presented. The propulsion and navigation system models are used to evaluate flight-testing methods for evaluating fixed-wing sUAS performance. A brief airframe analysis is presented to provide a foundation for assessing the efficacy of the flight-test methods. The flight-testing presented in this work is focused on validating the aircraft drag polar, zero-lift drag coefficient, and span efficiency factor. Three methods are detailed and evaluated for estimating these design parameters. Specific focus is placed on the influence of propulsion and navigation system uncertainty on the resulting performance data. Performance estimates are used in conjunction with the propulsion model to estimate the impact sensor and measurement uncertainty on the endurance and range of a fixed-wing sUAS. Endurance and range results for a simplistic power available model are compared to the Reynolds-dependent model presented in this work. Additional parameter sensitivity analysis related to state estimation uncertainties encountered in flight-testing are presented. Results from these analyses indicate that the sub-system models introduced in this work are of first-order importance, on the order of 5-10% change in range and endurance, in assessing the performance of a fixed-wing sUAS.
Example-based learning: effects of model expertise in relation to student expertise.
Boekhout, Paul; van Gog, Tamara; van de Wiel, Margje W J; Gerards-Last, Dorien; Geraets, Jacques
2010-12-01
Worked examples are very effective for novice learners. They typically present a written-out ideal (didactical) solution for learners to study. 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 (i.e., worked example based on advanced, third-year student model or expert physiotherapist model) in relation to students' expertise (i.e., first- or second-year) were investigated. One hundred and thirty-four physiotherapy students (61 first-year and 73 second-year). Design was 2 × 2 factorial with factors 'Student Expertise' (first-year vs. second-year) and 'Model Expertise' (expert vs. advanced student). Within expertise levels, students were randomly assigned to the Expert Example or the Advanced Student Example condition. All students studied two examples (content depending on their assigned condition) and then completed a retention and test task. They rated their invested mental effort after each example and test task. Second-year students invested less mental effort in studying the examples, and in performing the retention and transfer tasks than first-year students. They also performed better on the retention test, but not on the transfer test. In contrast to our hypothesis, there was no interaction between student expertise and model expertise: all students who had studied the Expert examples performed better on the transfer test than students who had studied Advanced Student Examples. This study suggests that when worked examples are based on actual performance, rather than an ideal procedure, expert models are to be preferred over advanced student models.
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.
NASA Technical Reports Server (NTRS)
Ramaswamy, Shankar; Banerjee, Prithviraj
1994-01-01
Appropriate data distribution has been found to be critical for obtaining good performance on Distributed Memory Multicomputers like the CM-5, Intel Paragon and IBM SP-1. It has also been found that some programs need to change their distributions during execution for better performance (redistribution). This work focuses on automatically generating efficient routines for redistribution. We present a new mathematical representation for regular distributions called PITFALLS and then discuss algorithms for redistribution based on this representation. One of the significant contributions of this work is being able to handle arbitrary source and target processor sets while performing redistribution. Another important contribution is the ability to handle an arbitrary number of dimensions for the array involved in the redistribution in a scalable manner. Our implementation of these techniques is based on an MPI-like communication library. The results presented show the low overheads for our redistribution algorithm as compared to naive runtime methods.
Tracking accuracy assessment for concentrator photovoltaic systems
NASA Astrophysics Data System (ADS)
Norton, Matthew S. H.; Anstey, Ben; Bentley, Roger W.; Georghiou, George E.
2010-10-01
The accuracy to which a concentrator photovoltaic (CPV) system can track the sun is an important parameter that influences a number of measurements that indicate the performance efficiency of the system. This paper presents work carried out into determining the tracking accuracy of a CPV system, and illustrates the steps involved in gaining an understanding of the tracking accuracy. A Trac-Stat SL1 accuracy monitor has been used in the determination of pointing accuracy and has been integrated into the outdoor CPV module test facility at the Photovoltaic Technology Laboratories in Nicosia, Cyprus. Results from this work are provided to demonstrate how important performance indicators may be presented, and how the reliability of results is improved through the deployment of such accuracy monitors. Finally, recommendations on the use of such sensors are provided as a means to improve the interpretation of real outdoor performance.
Working memory and inattentional blindness.
Bredemeier, Keith; Simons, Daniel J
2012-04-01
Individual differences in working memory predict many aspects of cognitive performance, especially for tasks that demand focused attention. One negative consequence of focused attention is inattentional blindness, the failure to notice unexpected objects when attention is engaged elsewhere. Yet, the relationship between individual differences in working memory and inattentional blindness is unclear; some studies have found that higher working memory capacity is associated with greater noticing, but others have found no direct association. Given the theoretical and practical significance of such individual differences, more definitive tests are needed. In two studies with large samples, we tested the relationship between multiple working memory measures and inattentional blindness. Individual differences in working memory predicted the ability to perform an attention-demanding tracking task, but did not predict the likelihood of noticing an unexpected object present during the task. We discuss the reasons why we might not expect such individual differences in noticing and why other studies may have found them.
Working memory-driven attention improves spatial resolution: Support for perceptual enhancement.
Pan, Yi; Luo, Qianying; Cheng, Min
2016-08-01
Previous research has indicated that attention can be biased toward those stimuli matching the contents of working memory and thereby facilitates visual processing at the location of the memory-matching stimuli. However, whether this working memory-driven attentional modulation takes place on early perceptual processes remains unclear. Our present results showed that working memory-driven attention improved identification of a brief Landolt target presented alone in the visual field. Because the suprathreshold target appeared without any external noise added (i.e., no distractors or masks), the results suggest that working memory-driven attention enhances the target signal at early perceptual stages of visual processing. Furthermore, given that performance in the Landolt target identification task indexes spatial resolution, this attentional facilitation indicates that working memory-driven attention can boost early perceptual processing via enhancement of spatial resolution at the attended location.
Ihne, Jessica L; Gallagher, Natalie M; Sullivan, Marie; Callicott, Joseph H; Green, Adam E
2016-01-01
Perhaps the most widely studied effect to emerge from the combination of neuroimaging and human genetics is the association of the COMT-Val(108/158)Met polymorphism with prefrontal activity during working memory. COMT-Val is a putative risk factor in schizophrenia, which is characterized by disordered prefrontal function. Work in healthy populations has sought to characterize mechanisms by which the valine (Val) allele may lead to disadvantaged prefrontal cognition. Lower activity in methionine (Met) carriers has been interpreted as advantageous neural efficiency. Notably, however, studies reporting COMT effects on neural efficiency have generally not reported working memory performance effects. Those studies have employed relatively low/easy working memory loads. Higher loads are known to elicit individual differences in working memory performance that are not visible at lower loads. If COMT-Met confers greater neural efficiency when working memory is easy, a reasonable prediction is that Met carriers will be better able to cope with increasing demand for neural resources when working memory becomes difficult. To our knowledge, this prediction has thus far gone untested. Here, we tested performance on three working memory tasks. Performance on each task was measured at multiple levels of load/difficulty, including loads more demanding than those used in prior studies. We found no genotype-by-load interactions or main effects of COMT genotype on accuracy or reaction time. Indeed, even testing for performance differences at each load of each task failed to find a single significant effect of COMT genotype. Thus, even if COMT genotype has the effects on prefrontal efficiency that prior work has suggested, such effects may not directly impact high-load working memory ability. The present findings accord with previous evidence that behavioral effects of COMT are small or nonexistent and, more broadly, with a growing consensus that substantial effects on phenotype will not emerge from candidate gene studies. Copyright © 2015 Elsevier Ltd. All rights reserved.
Thermionic converter performance with oxide collectors
NASA Technical Reports Server (NTRS)
Lieb, D.; Goodale, D.; Briere, T.; Balestra, C.
1977-01-01
Thermionic converters using a variety of metal oxide collector surfaces have been fabricated and tested. Both work function and power output data are presented and evaluated. Oxides of barium, strontium, zinc, tungsten and titanium have been incorporated into a variable spacing converter. Tungsten oxide was found to give the highest converter performance and to furnish oxygen for the emitter at the same time. Oxygenated emitters operate at reduced cesium pressure with an increase in electrode spacing. Electron spectroscopy for chemical analysis (ESCA) performed on several tungsten oxide collectors showed cesium penetration of the oxide layer, possibly forming a cesium tungstate bronze. Titanium oxide showed high performance but did not furnish oxygen for the emitter; strontium oxide, in the form of a sprayed layer, appeared to dissociate in the presence of cesium. Sprayed coatings of barium and zinc oxides produced collector work functions of about 1.3 eV, but had excessive series resistance. Lanthanum hexaboride, in combination with oxygen introduced through a silver tube, and cesium produced a low work function collector and better than average performance.
Linking working memory and long-term memory: a computational model of the learning of new words.
Jones, Gary; Gobet, Fernand; Pine, Julian M
2007-11-01
The nonword repetition (NWR) test has been shown to be a good predictor of children's vocabulary size. NWR performance has been explained using phonological working memory, which is seen as a critical component in the learning of new words. However, no detailed specification of the link between phonological working memory and long-term memory (LTM) has been proposed. In this paper, we present a computational model of children's vocabulary acquisition (EPAM-VOC) that specifies how phonological working memory and LTM interact. The model learns phoneme sequences, which are stored in LTM and mediate how much information can be held in working memory. The model's behaviour is compared with that of children in a new study of NWR, conducted in order to ensure the same nonword stimuli and methodology across ages. EPAM-VOC shows a pattern of results similar to that of children: performance is better for shorter nonwords and for wordlike nonwords, and performance improves with age. EPAM-VOC also simulates the superior performance for single consonant nonwords over clustered consonant nonwords found in previous NWR studies. EPAM-VOC provides a simple and elegant computational account of some of the key processes involved in the learning of new words: it specifies how phonological working memory and LTM interact; makes testable predictions; and suggests that developmental changes in NWR performance may reflect differences in the amount of information that has been encoded in LTM rather than developmental changes in working memory capacity.
Vahle-Hinz, Tim
2016-10-01
In nonregular forms of employment, such as fixed-term or temporary agency work, 2 sources of stress must be distinguished: task-related stress components (e.g., time pressure) and employment-related stress components (e.g., effort to maintain employment). The present study investigated the relationship between task- and employment-related demands and resources and indicators of strain, well-being, work engagement, and self-rated performance in a sample of nonregular employed workers. Using a 2-wave longitudinal design, the results of autoregressive cross-lagged structural equation models demonstrated that time pressure, as a task-related demand, is positively related to strain and negatively related to well-being and self-rated performance. Autonomy, as a task-related resource, exhibited no significant relationships in the current study. Employment-related demands exhibited negative relationships with well-being and work engagement as well as negative and positive relationships with self-rated performance over time. Employment-related resources were primarily positive predictors of well-being and self-rated performance. Fit indices of comparative models indicated that reciprocal effect models (which enable causal and reverse effects) best fit the data. Accordingly, demands and resources predicted strain, well-being, work engagement, and self-rated performance over time and vice versa. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Two-stroke S.I. engine competitive to four-stroke engine in terms of the exhaust emission
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pavletic, R.; Trenc, F.
1994-09-01
A model engine with disintegrated working cycle was built. Its operation is not autonomous; compression of the working air is performed separately outside the engine by the compressed-air line supply. Pre-compressed charge together with the injected fuel is introduced in the combustion chamber. The model engine makes possible to determine indicated performance characteristics and its emission capability. Effective measured engine characteristics are of course not comparable with those obtained by a practical engine. The model presented is a two-stroke cycle engine. Exhaust emission picture of the presented engine is comparable with the emission of a modern four-stroke engine. 2 refs.,more » 13 figs., 2 tabs.« less
Attachment anxiety benefits from security priming: Evidence from working memory performance
2018-01-01
The present study investigates the relationship between the attachment dimensions (anxious vs. avoidance) and the cognitive performance of individuals, specifically whether the attachment dimensions would predict the working memory (WM) performance. In the n-back task, reflecting the WM capacity, both attachment related and non-attachment related words were used. Participants were randomly assigned into two groups that received either the secure or the neutral subliminal priming. In the secure priming condition, the aim was to induce sense of security by presenting secure attachment words prior to the n-back task performance. In neutral priming condition, neutral words that did not elicit sense of security were presented. Structural equation modeling revealed divergent patterns for attachment anxiety and avoidance dimensions under the different priming conditions. In neutral priming condition, WM performance declined in terms of capacity in the n-back task for individuals who rated higher levels of attachment anxiety. However in the secure priming condition, WM performance was boosted in the n-back task for individuals who rated higher levels of attachment anxiety. In other words, the subliminal priming of the security led to increased WM capacity of individuals who rated higher levels of attachment anxiety. This effect, however, was not observed for higher levels of attachment avoidance. Results are discussed along the lines of hyperactivation and deactivation strategies of the attachment system. PMID:29522549
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
Design fabrication and installation of a yaw measuring device
NASA Technical Reports Server (NTRS)
1979-01-01
The results of work performed in the development and testing of a yaw measuring device are summarized. A review of the yaw measurement method; and the techniques and hardware needed for its implementation are presented. A description and summary of the tests performed at the U.S. Bureau of Mines Bruceton facility are included. Conclusions are summarized and recommendations for a unit capable of operation in a mine environment are presented.
Areepattamannil, Shaljan; Abdelfattah, Faisal; Mahasneh, Randa Ali; Khine, Myint Swe; Welch, Anita G; Melkonian, Michael; Al Nuaimi, Samira Ahmed
2016-01-01
Over half-a-million adolescents take part in each cycle of the Program for International Student Assessment (PISA). Yet often, researchers and policy makers across the globe tend to focus their attention primarily on the academic trajectories of adolescents hailing from highly successful education systems. Hence, a vast majority of the adolescent population who regionally and globally constitute the 'long tail of underachievement' often remain unnoticed and underrepresented in the growing literature on adolescents' academic trajectories. The present study, therefore, explored the relations of dispositions toward mathematics, subjective norms in mathematics, and perceived control of success in mathematics to mathematics work ethic as well as mathematics performance; and the mediational role of mathematics work ethic in the association between dispositional, normative, and control beliefs and mathematics performance among adolescents in one of the lowest performing education systems, Qatar. Structural equation modeling (SEM) analyses revealed that Qatari adolescents' dispositional, normative, and control beliefs about mathematics were significantly associated with their mathematics work ethic and mathematics performance, and mathematics work ethic significantly mediated the relationship between dispositional, normative, and control beliefs about mathematics and mathematics performance. However, multi-group SEM analyses indicated that these relationships were not invariant across the gender and the SES groups. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Javitt, Daniel C; Rabinowicz, Esther; Silipo, Gail; Dias, Elisa C
2007-03-01
Deficits in working memory performance are among the most widely replicated findings in schizophrenia. Roles of encoding vs. memory retention in working memory remain unresolved. The present study evaluated working memory performance in schizophrenia using an AX-type continuous performance test (AX-CPT) paradigm. Participants included 48 subjects with schizophrenia and 27 comparison subjects. Behavior was obtained in 3 versions of the task, which differed based upon ease of cue interoperability. In a simple cue version of the task, cue letters were replaced with red or green circles. In the complex cue version, letter/color conjunctions served as cues. In the base version of the task, patients showed increased rates of false alarms to invalidly cued targets, similar to prior reports. However, when the cue stimuli were replaced with green or red circles to ease interpretation, patients showed similar false alarm rates to controls. When feature conjunction cues were used, patients were also disproportionately affected relative to controls. No significant group by interstimulus interval interaction effects were observed in either the simple or complex cue conditions, suggesting normal retention of information even in the presence of overall performance decrements. These findings suggest first, that cue manipulation disproportionately affects AX-CPT performance in schizophrenia and, second, that substantial behavioral deficits may be observed on working memory tasks even in the absence of disturbances in mnemonic retention.
Kretschmer, Veronika; Schmidt, Klaus-Helmut; Griefahn, Barbara
2013-11-01
The present study examined whether the relationship between light exposure and cognitive functioning is mediated by psychological well-being in elderly persons working night shifts. The role of psychological well-being has been neglected so far in the relationship between bright light and cognitive performance. Sleepiness and mood were applied as indicators of psychological well-being. Cognitive functioning was examined in terms of concentration, working memory, and divided attention. A total of thirty-two test persons worked in three consecutive simulated night shifts, 16 under bright light (3,000 lux) and 16 under room light (300 lux). Concentration, working memory, and divided attention were measured by computerised tasks. The hypothesised mediators were recorded by questionnaires. Mediation analyses were conducted for estimating direct, total, and indirect effects in simple mediation models. Results indicate that sleepiness and mood did not function as mediators in the prediction of concentration, working memory, and/or divided attention by light exposure. Sleepiness led to an underestimation of the positive bright-light effect on concentration performance. Mood showed only a random effect due to the positive bright-light effect on working memory. Sleepiness and mood could completely be excluded as mediators in the relationship between light exposure and cognitive functioning. This study underlines that psychological well-being of elderly persons is not a critical component in the treatment of bright light on cognitive performance in the night shift workplace. In summary, it becomes evident that bright light has a strong direct and independent effect on cognitive performance, particularly on working memory and concentration.
Methodology of selecting dozers for lignite open pit mines in Serbia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stojanovic, D.; Ignjatovic, D.; Kovacevic, S.
1996-12-31
Apart from the main production processes (coal and overburden mining, rail conveyors transportation and storage of excavated masses) performed by great-capacity mechanization at open pit mines, numerous and different auxiliary works, that often have crucial influence on both the work efficiency of main equipment and the maintenance of optimum technical conditions of machines and plants covering technological system of open pit, are present. Successful realization of work indispensably requires a proper and adequate selection of auxiliary machines according to their type quantity, capacity, power etc. thus highly respecting specific conditions existing at each and every open pit mine. A dozermore » is certainly the most important and representative auxiliary machine at single open pit mine. It is widely used in numerous works that, in fact, are preconditions for successful work of the main mechanization and consequently the very selection of a dozer ranges among the most important operations when selecting mechanization. This paper presents the methodology of dozers selection when lignite open pit mines are concerned. A mathematical model defining the volume of work required for dozers to perform at open pit mines and consequently the number of necessary dozers was designed. The model underwent testing in practice at big open pit mines and can be used in design of future open pits mines.« less
ERIC Educational Resources Information Center
Macy, Barry A.; Mirvis, Philip H.
1982-01-01
A standardized methodology for identifying, defining, and measuring work behavior and performance rather than production, and a methodology that estimates the costs and benefits of work innovation are presented for assessing organizational effectiveness and program costs versus benefits in organizational change programs. Factors in a cost-benefit…
ERIC Educational Resources Information Center
Devos, Christelle; Dupriez, Vincent; Paquay, Leopold
2012-01-01
We investigate how the social working environment predicts beginning teachers' self-efficacy and feelings of depression. Two quantitative studies are presented. The results show that the goal structure of the school culture (mastery or performance orientation) predicts both outcomes. Frequent collaborative interactions with colleagues are related…
The Influence of Domain Knowledge on the Functional Capacity of Working Memory
ERIC Educational Resources Information Center
Ricks, Travis Rex; Wiley, Jennifer
2009-01-01
Theories of expertise have proposed that superior cognitive performance is in part due to increases in the functional capacity of working memory during domain-related tasks. Consistent with this approach Fincher-Kiefer et al. (1988), found that domain knowledge increased scores on baseball-related reading span tasks. The present studies extended…
Investigating the Effects of Veridicality on Age Differences in Verbal Working Memory
ERIC Educational Resources Information Center
Shake, Matthew C.; Perschke, Meghan K.
2013-01-01
In the typical loaded verbal working memory (WM) span task (e.g., Daneman & Carpenter, 1980), participants judge the veridicality of a series of sentences while simultaneously storing the sentence final word for later recall. Performance declines as the number of sentences is increased; aging exacerbates this decline. The present study examined…
Male Social Workers Working with Men Who Batter: Dilemmas in Gender Identity
ERIC Educational Resources Information Center
Bailey, Benjamin; Buchbinder, Eli; Eisikovits, Zvi
2011-01-01
Research into the impact of dealing with intimate partner violence has focused mainly on women who treated victims. The present article explores the interaction between male social workers and battering men. The sample included 15 male social workers who worked with battering men in social services. Data collection was performed through…
How the bimodal format of presentation affects working memory: an overview.
Mastroberardino, Serena; Santangelo, Valerio; Botta, Fabiano; Marucci, Francesco S; Olivetti Belardinelli, Marta
2008-03-01
The best format in which information that has to be recalled is presented has been investigated in several studies, which focused on the impact of bimodal stimulation on working memory performance. An enhancement of participant's performance in terms of correct recall has been repeatedly found, when bimodal formats of presentation (i.e., audiovisual) were compared to unimodal formats (i.e, either visual or auditory), in providing implications for multimedial learning. Several theoretical frameworks have been suggested in order to account for the bimodal advantage, ranging from those emphasizing early stages of processing (such as automatic alerting effects or multisensory integration processes) to those centred on late stages of processing (as postulated by the dual coding theory). The aim of this paper is to review previous contributions to this topic, providing a comprehensive theoretical framework, which is updated by the latest empirical studies.
NASA Astrophysics Data System (ADS)
Athaudage, Chandranath R. N.; Bradley, Alan B.; Lech, Margaret
2003-12-01
A dynamic programming-based optimization strategy for a temporal decomposition (TD) model of speech and its application to low-rate speech coding in storage and broadcasting is presented. In previous work with the spectral stability-based event localizing (SBEL) TD algorithm, the event localization was performed based on a spectral stability criterion. Although this approach gave reasonably good results, there was no assurance on the optimality of the event locations. In the present work, we have optimized the event localizing task using a dynamic programming-based optimization strategy. Simulation results show that an improved TD model accuracy can be achieved. A methodology of incorporating the optimized TD algorithm within the standard MELP speech coder for the efficient compression of speech spectral information is also presented. The performance evaluation results revealed that the proposed speech coding scheme achieves 50%-60% compression of speech spectral information with negligible degradation in the decoded speech quality.
Health, Safety and Performance in High Altitude Observatories: A Sustainable Approach
NASA Astrophysics Data System (ADS)
Böcker, Michael; Vogt, Joachim; Christ, Oliver; Müller-Leonhardt, Alice
2009-09-01
The research project “Optimising Performance, Health and Safety in High Altitude Observatories” was initiated by ESO to establish an approach to promote the well-being of staff working at its high altitude observatories, and in particular at the Antiplano de Chajnantor. A survey by a questionnaire given to both workers and visitors was employed to assess the effects of working conditions at high altitude. Earlier articles have outlined the project and reported early results. The final results and conclusions are presented, together with a concept for sustainable development to improve the performance, health and safety at high altitude employing Critical Incident Stress Management.
2016 Standard Scenarios Report: A U.S. Electricity Sector Outlook
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cole, Wesley; Mai, Trieu; Logan, Jeffrey
This is the webinar presentation deck used to present the 2016 Standard Scenarios work. It discusses the Annual Technology Baseline (ATB) detailed cost and performance projections for electricity-generating technologies and the standard scenarios of the power sector modeling using ATB inputs.
23 CFR 660.519 - Missile installations and facilities.
Code of Federal Regulations, 2011 CFR
2011-04-01
... facilities. Should damage occur to public highways as a result of construction activities, the contractor... the work performed. Claims shall be presented to the contractor for this extraordinary maintenance and... the contract terms, the claim with the required supporting documentation shall be presented to the...
23 CFR 660.519 - Missile installations and facilities.
Code of Federal Regulations, 2012 CFR
2012-04-01
... facilities. Should damage occur to public highways as a result of construction activities, the contractor... the work performed. Claims shall be presented to the contractor for this extraordinary maintenance and... the contract terms, the claim with the required supporting documentation shall be presented to the...
Supporting clinician educators to achieve “work-work balance”
Maniate, Jerry; Dath, Deepak; Cooke, Lara; Leslie, Karen; Snell, Linda; Busari, Jamiu
2016-01-01
Clinician Educators (CE) have numerous responsibilities in different professional domains, including clinical, education, research, and administration. Many CEs face tensions trying to manage these often competing professional responsibilities and achieve “work-work balance.” Rich discussions of techniques for work-work balance amongst CEs at a medical education conference inspired the authors to gather, analyze, and summarize these techniques to share with others. In this paper we present the CE’s “Four Ps”; these are practice points that support both the aspiring and established CE to help improve their performance and productivity as CEs, and allow them to approach work-work balance. PMID:28344698
ERIC Educational Resources Information Center
Bekele, Rahel; McPherson, Maggie
2011-01-01
This research work presents a Bayesian Performance Prediction Model that was created in order to determine the strength of personality traits in predicting the level of mathematics performance of high school students in Addis Ababa. It is an automated tool that can be used to collect information from students for the purpose of effective group…
A Tensor Product Formulation of Strassen's Matrix Multiplication Algorithm with Memory Reduction
Kumar, B.; Huang, C. -H.; Sadayappan, P.; ...
1995-01-01
In this article, we present a program generation strategy of Strassen's matrix multiplication algorithm using a programming methodology based on tensor product formulas. In this methodology, block recursive programs such as the fast Fourier Transforms and Strassen's matrix multiplication algorithm are expressed as algebraic formulas involving tensor products and other matrix operations. Such formulas can be systematically translated to high-performance parallel/vector codes for various architectures. In this article, we present a nonrecursive implementation of Strassen's algorithm for shared memory vector processors such as the Cray Y-MP. A previous implementation of Strassen's algorithm synthesized from tensor product formulas required working storagemore » of size O(7 n ) for multiplying 2 n × 2 n matrices. We present a modified formulation in which the working storage requirement is reduced to O(4 n ). The modified formulation exhibits sufficient parallelism for efficient implementation on a shared memory multiprocessor. Performance results on a Cray Y-MP8/64 are presented.« less
Dissociation of performance and subjective measures of workload
NASA Technical Reports Server (NTRS)
Yeh, Yei-Yu; Wickens, Christopher D.
1988-01-01
A theory is presented to identify sources that produce dissociations between performance and subjective measures of workload. The theory states that performance is determined by (1) amount of resources invested, (2) resource efficiency, and (3) degree of competition for common resources in a multidimensional space described in the multiple-resources model. Subjective perception of workload, multidimensional in nature, increases with greater amounts of resource investment and with greater demands on working memory. Performance and subjective workload measures dissociate when greater resources are invested to improve performance of a resource-limited task; when demands on working memory are increased by time-sharing between concurrent tasks or between display elements; and when performance is sensitive to resource competition and subjective measures are more sensitive to total investment. These dissociation findings and their implications are discussed and directions for future research are suggested.
Competition, Parental Involvement and Public School Performance.
ERIC Educational Resources Information Center
McMillan, Robert
This paper summarizes work from a dissertation that examines the determinants of public school performance, focusing on the roles of incentives and parental involvement. The thesis presents theory and related empirics. In the theory, it analyzes the effects of competition on public school productivity, with and without parental involvement, as…
Tales of New York City's Guerrilla Teaching Artists
ERIC Educational Resources Information Center
Katzoff, Howard Martin
2011-01-01
This article presents snapshots of an innovative program in which performing actor, musician, and dancer TAs work as substitute teachers. Through STARRRs (Substitute Teachers for the Arts and 3Rs) Program, New York City principals hire professional performers as licensed substitute teachers. Actors, musicians, and dancers bring their craft into…
Intermediality and the Child Performer
ERIC Educational Resources Information Center
Budd, Natasha
2016-01-01
This report details examples of praxis in the creation and presentation of "Joy Fear and Poetry": an intermedial theatre performance in which children aged 7-12 years generated aesthetic gestures using a range of new media forms. The impetus for the work's development was a desire to make an intervention into habituated patterns of…
DOT National Transportation Integrated Search
1978-10-01
This report presents a method that may be used to evaluate the reliability of performance of individual subjects, particularly in applied laboratory research. The method is based on analysis of variance of a tasks-by-subjects data matrix, with all sc...
The Human Resource Cycle as Basis of Human Resource Development System.
ERIC Educational Resources Information Center
Jereb, Janez
The primary aim of human-resource-development systems in companies is to improve organizational performance through satisfying the development needs of individual employees. This paper presents findings of a study that looked at how human-resource-development systems worked in practice, in particular, how performance management, selection,…
Six degree of freedom active vibration damping for space application
NASA Technical Reports Server (NTRS)
Haynes, Leonard S.
1993-01-01
Work performed during the period 1 Jan. - 31 Mar. 1993 on six degree of freedom active vibration damping for space application is presented. A performance and cost report is included. Topics covered include: actuator testing; mechanical amplifier design; and neural network control system development and experimental evaluation.
Interactions of Task and Subject Variables among Continuous Performance Tests
ERIC Educational Resources Information Center
Denney, Colin B.; Rapport, Mark D.; Chung, Kyong-Mee
2005-01-01
Background: Contemporary models of working memory suggest that target paradigm (TP) and target density (TD) should interact as influences on error rates derived from continuous performance tests (CPTs). The present study evaluated this hypothesis empirically in a typically developing, ethnically diverse sample of children. The extent to which…
Oesch, Peter; Meyer, Kathrin; Jansen, Beatrice; Kool, Jan
2015-06-01
The primary objective of this study is to evaluate the effect of Waddell signs (WS) on Functional Capacity Evaluation (FCE) in patients with chronic non-specific low back pain (CNSLBP) undergoing fitness for work evaluation. If an effect is observed, the secondary objective is to report performance of patients without WS in a standardized 1 day FCE protocol. Survey of patients with CNSLBP as their primary complaint, referred for fitness for work evaluation, age between 20 and 60 years. Main outcome measures were WS and performance during manual handling assessed with lifting from floor to waist, waist to crown, horizontal and one handed carry; grip strength with Jamar hand held Dynamometer; ambulation with stair climbing and six minute walking test; work postures with elevated work, forward bend standing, kneeling, and sitting. 145 male with a mean age of 44.5 years (±10.1), and 53 females with a mean age of 43.6 years (±11.0) were included. Mean days off work were in male 658 (±1,056) and in female 642 (±886). 33% of all patients presented positive WS. FCE performance in male and female patients with positive and negative WS differed significantly in all comparisons except grip strength of the dominant hand and sitting in female. Performance of patients with negative WS indicated a mean physical capacity corresponding to lightmedium work in females and medium work in males for both age groups. WS should be assessed for interpretation of FCE results. Despite long work absence, patients with CNSLBP with negative WS demonstrated a physical capacity corresponding to substantial physical work demands.
ERIC Educational Resources Information Center
Mathras, Michael S.
1993-01-01
Presents an activity that models the work of chemical engineers. Students design, fabricate, and perform mechanical tests on plaster matrix composites and compare the strength to mass ratios of several products. (PR)
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.
Long life technology work at Rockwell International Space Division
NASA Technical Reports Server (NTRS)
Huzel, D. K.
1974-01-01
This paper presents highlights of long-life technology oriented work performed at the Space Division of Rockwell International Corporation under contract to NASA. This effort included evaluation of Saturn V launch vehicle mechanical and electromechanical components for potential extended life capabilities, endurance tests, and accelerated aging experiments. A major aspect was evaluation of the components at the subassembly level (i.e., at the interface between moving surfaces) through in-depth wear analyses and assessments. Although some of this work is still in progress, preliminary conclusions are drawn and presented, together with the rationale for each. The paper concludes with a summary of the effort still remaining.
Optical RRH working in an all-optical fronthaul network
NASA Astrophysics Data System (ADS)
Zakrzewski, Zbigniew
2017-12-01
The paper presents an example of an optical RRH (Remote Radio Head) design, which is equipped with photonic components for direct connection to an all-optical network. The features that can be fulfilled by an all-optical network are indicated to support future 5G mobile networks. The demand for optical bandwidth in fronthaul/midhaul distribution network links, working in D-RoF and A-RoF formats was performed. The increase in demand is due to the very large traffic generated by the Optical Massive-MIMO RRH/RRU will work in format of an Active-Distributed Antenna System (A-DAS). An exemplary next-generation mobile network that will utilize O-RRH and an all-optical backbone is presented. All components of presented network will work in the Centralized/Cloud Radio Access Network (C-RAN) architecture, which is achievable by control with the use of the OpenFlow (OF).
NASA Technical Reports Server (NTRS)
Braunscheidel, Edward P.; Welch, Gerard E.; Skoch, Gary J.; Medic, Gorazd; Sharma, Om P.
2015-01-01
The measured aerodynamic performance of a compact, high work-factor, single-stage centrifugal compressor, comprising an impeller, diffuser, 90deg-bend, and exit guide vane is reported. Performance levels are based on steady-state total-pressure and total-temperature rake and angularity-probe data acquired at key machine rating planes during recent testing at NASA Glenn Research Center. Aerodynamic performance at the stage level is reported for operation between 70 to 105 percent of design corrected speed, with subcomponent (impeller, diffuser, and exit-guide-vane) flow field measurements presented and discussed at the 100 percent design-speed condition. Individual component losses from measurements are compared with pre-test CFD predictions on a limited basis.
NASA Technical Reports Server (NTRS)
Braunscheidel, Edward P.; Welch, Gerard E.; Skoch, Gary J.; Medic, Gorazd; Sharma, Om P.
2014-01-01
The measured aerodynamic performance of a compact, high work-factor, single-stage centrifugal compressor, comprising an impeller, diffuser, 90º-bend, and exit guide vane is reported. Performance levels are based on steady-state total-pressure and total-temperature rake and angularity-probe data acquired at key machine rating planes during recent testing at NASA Glenn Research Center. Aerodynamic performance at the stage level is reported for operation between 70 to 105% of design corrected speed, with subcomponent (impeller, diffuser, and exit-guide-vane) flow field measurements presented and discussed at the 100% design-speed condition. Individual component losses from measurements are compared with pre-test CFD predictions on a limited basis.
Directional hippocampal-prefrontal interactions during working memory.
Liu, Tiaotiao; Bai, Wenwen; Xia, Mi; Tian, Xin
2018-02-15
Working memory refers to a system that is essential for performing complex cognitive tasks such as reasoning, comprehension and learning. Evidence shows that hippocampus (HPC) and prefrontal cortex (PFC) play important roles in working memory. The HPC-PFC interaction via theta-band oscillatory synchronization is critical for successful execution of working memory. However, whether one brain region is leading or lagging relative to another is still unclear. Therefore, in the present study, we simultaneously recorded local field potentials (LFPs) from rat ventral hippocampus (vHPC) and medial prefrontal cortex (mPFC) and while the rats performed a Y-maze working memory task. We then applied instantaneous amplitudes cross-correlation method to calculate the time lag between PFC and vHPC to explore the functional dynamics of the HPC-PFC interaction. Our results showed a strong lead from vHPC to mPFC preceded an animal's correct choice during the working memory task. These findings suggest the vHPC-leading interaction contributes to the successful execution of working memory. Copyright © 2017. Published by Elsevier B.V.
ERIC Educational Resources Information Center
Chou, Mu-hsuan
2011-01-01
Cooperative learning has frequently been used in language classrooms, from in-class task-based group work to group presentations. Research suggests that cooperative learning provides mutual support, as well as successful and effective learning outcomes of tasks. The present research addressed a number of problems discovered in group oral…
Graphene as a long-term metal oxidation barrier: worse than nothing.
Schriver, Maria; Regan, William; Gannett, Will J; Zaniewski, Anna M; Crommie, Michael F; Zettl, Alex
2013-07-23
Anticorrosion and antioxidation surface treatments such as paint or anodization are a foundational component in nearly all industries. Graphene, a single-atom-thick sheet of carbon with impressive impermeability to gases, seems to hold promise as an effective anticorrosion barrier, and recent work supports this hope. We perform a complete study of the short- and long-term performance of graphene coatings for Cu and Si substrates. Our work reveals that although graphene indeed offers effective short-term oxidation protection, over long time scales it promotes more extensive wet corrosion than that seen for an initially bare, unprotected Cu surface. This surprising result has important implications for future scientific studies and industrial applications. In addition to informing any future work on graphene as a protective coating, the results presented here have implications for graphene's performance in a wide range of applications.
Assessment of a 40-kilowatt stirling engine for underground mining applications
NASA Technical Reports Server (NTRS)
Cairelli, J. E.; Kelm, G. G.; Slaby, J. G.
1982-01-01
An assessment of alternative power souces for underground mining applications was performed. A 40-kW Stirling research engine was tested to evaluate its performance and emission characteristics when operated with helium working gas and diesel fuel. The engine, the test facility, and the test procedures are described. Performance and emission data for the engine operating with helium working gas and diesel fuel are reported and compared with data obtained with hydrogen working gas and unleaded gasoline fuel. Helium diesel test results are compared with the characteristics of current diesel engines and other Stirling engines. External surface temperature data are also presented. Emission and temperature results are compared with the Federal requirements for diesel underground mine engines. The durability potential of Stirling engines is discussed on the basis of the experience gaind during the engine tests.
Negative social emotions and cognition: Shame, guilt and working memory impairments.
Cavalera, Cesare; Pepe, Alessandro; Zurloni, Valentino; Diana, Barbara; Realdon, Olivia; Todisco, Patrizia; Castelnuovo, Gianluca; Molinari, Enrico; Pagnini, Francesco
2018-05-23
Negative emotions can have an impact on a variety of cognitive domains, including Working Memory (WM). The present work investigated whether shame and guilt modulate WM performance in a dual-task test both in a non-clinical and a clinical population. In Experiment 1, 76 non-clinical participants performed a dual-task before and after being randomly assigned to shame, guilt or neutral inductions elicited by the writing of autobiographical past experiences. Shame and guilt elicitations were related to impaired WM performances. In Experiment 2, 65 clinical inpatients with eating disorders were assigned to the same procedure. The negative relationship of self-conscious emotions and WM was confirmed. Taken together these results suggest that shame and guilt are related to impairments of WM in both clinical and non-clinical participants. Copyright © 2018 Elsevier B.V. All rights reserved.
Saliasi, Emi; Geerligs, Linda; Lorist, Monicque M.; Maurits, Natasha M.
2014-01-01
To investigate which neural correlates are associated with successful working memory performance, fMRI was recorded in healthy younger and older adults during performance on an n-back task with varying task demands. To identify functional networks supporting working memory processes, we used independent component analysis (ICA) decomposition of the fMRI data. Compared to younger adults, older adults showed a larger neural (BOLD) response in the more complex (2-back) than in the baseline (0-back) task condition, in the ventral lateral prefrontal cortex (VLPFC) and in the right fronto-parietal network (FPN). Our results indicated that a higher BOLD response in the VLPFC was associated with increased performance accuracy in older adults, in both the baseline and the more complex task condition. This ‘BOLD-performance’ relationship suggests that the neural correlates linked with successful performance in the older adults are not uniquely related to specific working memory processes present in the complex but not in the baseline task condition. Furthermore, the selective presence of this relationship in older but not in younger adults suggests that increased neural activity in the VLPFC serves a compensatory role in the aging brain which benefits task performance in the elderly. PMID:24911016
NASA Astrophysics Data System (ADS)
Granados, Victor H.; Pinheiro, Mario J.; Sá, Paulo A.
2017-12-01
The goal of this article is to contribute to the advancement and the improvement of the performances of electrohydrodynamic (EHD) propulsion systems for space missions, especially in what concerns the control of the geometries of the electrodes and the employed gas and its efficiency. We use a previously developed self-consistent model to compare and study the performance of these systems using three different working gases (argon, nitrogen, and oxygen) in terms of net thrust production and thrust-to-power efficiency of single-stage EHD thrusters. In order to verify the dependency of those physical parameters on the configuration and orientation of the electrodes, we conduct systematic simulations of three thruster cathode configurations (conical, cylindrical, and funnel-like). In the present study, the working pressure is ≈1.3 kPa (10 Torr), well below the normal atmospheric pressure, and the gas temperature is 300 K. A similar systematic investigation was conducted in a recent paper at a relatively much lower pressure of 0.5 Torr (20 times less) for the same cathode duct geometries and working gases, which permit to compare the performances of the considered thrusters and gases at these two pressures; then and now, the distance between the electrodes is fixed at 28 mm, but in addition to the pressure, other parameters were modified. Thus, the input voltage is fixed at 3 kV, and the resistance of the ballast varies in the range of 500-5000 MΩ. Nitrogen gas performed better than argon for all proposed geometries, doubling the produced thrust while presenting higher T/P ratios in almost all cases. Oxygen presented significantly better performance than nitrogen's and argon's, e.g., funnel like cathode configuration presented a net thrust higher than 0.1 mN, about one order of magnitude higher than nitrogen's.
Fuermaier, Anselm B M; Tucha, Oliver; Koerts, Janneke; Lange, Klaus W; Weisbrod, Matthias; Aschenbrenner, Steffen; Tucha, Lara
2017-12-01
The assessment of performance validity is an essential part of the neuropsychological evaluation of adults with attention-deficit/hyperactivity disorder (ADHD). Most available tools, however, are inaccurate regarding the identification of noncredible performance. This study describes the development of a visuospatial working memory test, including a validity indicator for noncredible cognitive performance of adults with ADHD. Visuospatial working memory of adults with ADHD (n = 48) was first compared to the test performance of healthy individuals (n = 48). Furthermore, a simulation design was performed including 252 individuals who were randomly assigned to either a control group (n = 48) or to 1 of 3 simulation groups who were requested to feign ADHD (n = 204). Additional samples of 27 adults with ADHD and 69 instructed simulators were included to cross-validate findings from the first samples. Adults with ADHD showed impaired visuospatial working memory performance of medium size as compared to healthy individuals. Simulation groups committed significantly more errors and had shorter response times as compared to patients with ADHD. Moreover, binary logistic regression analysis was carried out to derive a validity index that optimally differentiates between true and feigned ADHD. ROC analysis demonstrated high classification rates of the validity index, as shown in excellent specificity (95.8%) and adequate sensitivity (60.3%). The visuospatial working memory test as presented in this study therefore appears sensitive in indicating cognitive impairment of adults with ADHD. Furthermore, the embedded validity index revealed promising results concerning the detection of noncredible cognitive performance of adults with ADHD. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Pulsed Electric Propulsion Thrust Stand Calibration Method
NASA Technical Reports Server (NTRS)
Wong, Andrea R.; Polzin, Kurt A.; Pearson, J. Boise
2011-01-01
The evaluation of the performance of any propulsion device requires the accurate measurement of thrust. While chemical rocket thrust is typically measured using a load cell, the low thrust levels associated with electric propulsion (EP) systems necessitate the use of much more sensitive measurement techniques. The design and development of electric propulsion thrust stands that employ a conventional hanging pendulum arm connected to a balance mechanism consisting of a secondary arm and variable linkage have been reported in recent publications by Polzin et al. These works focused on performing steady-state thrust measurements and employed a static analysis of the thrust stand response. In the present work, we present a calibration method and data that will permit pulsed thrust measurements using the Variable Amplitude Hanging Pendulum with Extended Range (VAHPER) thrust stand. Pulsed thrust measurements are challenging in general because the pulsed thrust (impulse bit) occurs over a short timescale (typically 1 micros to 1 millisecond) and cannot be resolved directly. Consequently, the imparted impulse bit must be inferred through observation of the change in thrust stand motion effected by the pulse. Pulsed thrust measurements have typically only consisted of single-shot operation. In the present work, we discuss repetition-rate pulsed thruster operation and describe a method to perform these measurements. The thrust stand response can be modeled as a spring-mass-damper system with a repetitive delta forcing function to represent the impulsive action of the thruster.
Photonic crystal fiber technology for compact fiber-delivered high-power ultrafast fiber lasers
NASA Astrophysics Data System (ADS)
Triches, Marco; Michieletto, Mattia; Johansen, Mette M.; Jakobsen, Christian; Olesen, Anders S.; Papior, Sidsel R.; Kristensen, Torben; Bondue, Magalie; Weirich, Johannes; Alkeskjold, Thomas T.
2018-02-01
Photonic crystal fiber (PCF) technology has radically impacted the scientific and industrial ultrafast laser market. Reducing platform dimensions are important to decrease cost and footprint while maintaining high optical efficiency. We present our recent work on short 85 μm core ROD-type fiber amplifiers that maintain single-mode performance and excellent beam quality. Robust long-term performance at 100 W average power and 250 kW peak power in 20 ps pulses at 1030 nm wavelength is presented, exceeding 500 h with stable performance in terms of both polarization and power. In addition, we present our recent results on hollow-core ultrafast fiber delivery maintaining high beam quality and polarization purity.
NASA Technical Reports Server (NTRS)
White, R. J.
1974-01-01
The present work discusses a model of the cardiovascular system and related subsystems capable of long-term simulations of the type desired for in-space hypogravic human physiological performance prediction. The discussion centers around the model of Guyton and modifications of it. In order to draw attention to the fluid handling capabilities of the model, one of several transfusion simulations performed is presented, namely, the isotonic saline transfusion simulation.
Marques, Rita; Gregório, João; Pinheiro, Fernando; Póvoa, Pedro; da Silva, Miguel Mira; Lapão, Luís Velez
2017-01-31
Hospital-acquired infections are still amongst the major problems health systems are facing. Their occurrence can lead to higher morbidity and mortality rates, increased length of hospital stay, and higher costs for both hospital and patients. Performing hand hygiene is a simple and inexpensive prevention measure, but healthcare workers' compliance with it is often far from ideal. To raise awareness regarding hand hygiene compliance, individual behaviour change and performance optimization, we aimed to develop a gamification solution that collects data and provides real-time feedback accurately in a fun and engaging way. A Design Science Research Methodology (DSRM) was used to conduct this work. DSRM is useful to study the link between research and professional practices by designing, implementing and evaluating artifacts that address a specific need. It follows a development cycle (or iteration) composed by six activities. Two work iterations were performed applying gamification components, each using a different indoor location technology. Preliminary experiments, simulations and field studies were performed in an Intensive Care Unit (ICU) of a Portuguese tertiary hospital. Nurses working on this ICU were in a focus group during the research, participating in several sessions across the implementation process. Nurses enjoyed the concept and considered that it allows for a unique opportunity to receive feedback regarding their performance. Tests performed on the indoor location technology applied in the first iteration regarding distances estimation presented an unacceptable lack of accuracy. Using a proximity-based technique, it was possible to identify the sequence of positions, but beacons presented an unstable behaviour. In the second work iteration, a different indoor location technology was explored but it did not work properly, so there was no chance of testing the solution as a whole (gamification application included). Combining automated monitoring systems with gamification seems to be an innovative and promising approach, based on the already achieved results. Involving nurses in the project since the beginning allowed to align the solution with their needs. Despite strong evolution through recent years, indoor location technologies are still not ready to be applied in the healthcare field with nursing wards.
NASA Astrophysics Data System (ADS)
Bodlak, Maciej; Dmytryk, Dominik; Mertuszka, Piotr; Szumny, Marcin; Tomkiewicz, Grzegorz
2018-01-01
The article describes the monitoring system of blasthole drilling process called HNS (Hole Navigation System), which was used in blasting works performed by Maxam Poland Ltd. Developed by Atlas Copco's, the HNS system - using satellite data - allows for a very accurate mapping of the designed grid of blastholes. The article presents the results of several conducted measurements of ground vibrations triggered by blasting, designed and performed using traditional technology and using the HNS system and shows first observations in this matter.
NASA Astrophysics Data System (ADS)
Chen, J.; Xue, L.
2012-06-01
This paper summarizes our research on laser cladding of high-vanadium CPM® tool steels (3V, 9V, and 15V) onto the surfaces of low-cost hardened H13 hot-work tool steel to substantially enhance resistance against abrasive wear. The results provide great potential for fabricating high-performance automotive tooling (including molds and dies) at affordable cost. The microstructure and hardness development of the laser-clad tool steels so obtained are presented as well.
Up-conversion of MMW radiation to visual band using glow discharge detector and silicon detector
NASA Astrophysics Data System (ADS)
Aharon Akram, Avihai; Rozban, Daniel; Abramovich, Amir; Yitzhaky, Yitzhak; Kopeika, Natan S.
2016-10-01
In this work we describe and demonstrate a method for up-conversion of millimeter wave (MMW) radiation to the visual band using a very inexpensive miniature Glow Discharge Detector (GDD), and a silicon detector (photodetector). Here we present 100 GHz up-conversion images based on measuring the visual light emitting from the GDD rather than its electrical current. The results showed better response time of 480 ns and better sensitivity compared to the electronic detection that was performed in our previous work. In this work we performed MMW imaging based on this method using a GDD lamp, and a photodetector to measure GDD light emission.
Modulation of working memory updating: Does long-term memory lexical association matter?
Artuso, Caterina; Palladino, Paola
2016-02-01
The aim of the present study was to investigate how working memory updating for verbal material is modulated by enduring properties of long-term memory. Two coexisting perspectives that account for the relation between long-term representation and short-term performance were addressed. First, evidence suggests that performance is more closely linked to lexical properties, that is, co-occurrences within the language. Conversely, other evidence suggests that performance is linked more to long-term representations which do not entail lexical/linguistic representations. Our aim was to investigate how these two kinds of long-term memory associations (i.e., lexical or nonlexical) modulate ongoing working memory activity. Therefore, we manipulated (between participants) the strength of the association in letters based on either frequency of co-occurrences (lexical) or contiguity along the sequence of the alphabet (nonlexical). Results showed a cost in working memory updating for strongly lexically associated stimuli only. Our findings advance knowledge of how lexical long-term memory associations between consonants affect working memory updating and, in turn, contribute to the study of factors which impact the updating process across memory systems.
Sleep Loss and Fatigue in Shift Work and Shift Work Disorder
Åkerstedt, Torbjörn; Wright, Kenneth P.
2010-01-01
Shift work is highly prevalent in industrialized societies (>20%) but, when it includes night work, it has pronounced negative effects on sleep, subjective and physiological sleepiness, performance, accident risk, as well as on health outcomes such as cardiovascular disease and certain forms of cancer. The reason is the conflict between the day oriented circadian physiology and the requirement for work and sleep at the “wrong” biological time of day. Other factors that negatively impact work shift sleepiness and accident risk include long duration shifts greater than 12 hours and individual vulnerability for phase intolerance that may lead to a diagnosis of shift work disorder; i.e., those shift workers with the greatest sleepiness and performance impairment during the biological night and insomnia during the biological day. Whereas some countermeasures may be used to ameliorate the negative impact of shift work on nighttime sleepiness and daytime insomnia (combined countermeasures may be the best available), there seems at present to be no way to eliminate most of the negative effects of shift work on human physiology and cognition. PMID:20640236
Taming a wandering attention: short-form mindfulness training in student cohorts.
Morrison, Alexandra B; Goolsarran, Merissa; Rogers, Scott L; Jha, Amishi P
2014-01-06
Mindfulness training (MT) is a form of mental training in which individuals engage in exercises to cultivate an attentive, present centered, and non-reactive mental mode. The present study examines the putative benefits of MT in University students for whom mind wandering can interfere with learning and academic success. We tested the hypothesis that short-form MT (7 h over 7 weeks) contextualized for the challenges and concerns of University students may reduce mind wandering and improve working memory. Performance on the sustained attention to response task (SART) and two working memory tasks (operation span, delayed-recognition with distracters) was indexed in participants assigned to a waitlist control group or the MT course. Results demonstrated MT-related benefits in SART performance. Relative to the control group, MT participants had higher task accuracy and self-reported being more "on-task" after the 7-week training period. MT did not significantly benefit the operation span task or accuracy on the delayed-recognition task. Together these results suggest that while short-form MT did not bolster working memory task performance, it may help curb mind wandering and should, therefore, be further investigated for its use in academic contexts.
A Method to Determine an Organization’s Compatibility with Hybrid Workspaces
2014-03-27
workers were present and assumed to be working. As early as the 1980s , private sector organizations began to evolve from task-based work to process...fact that people may utilize multiple physical spaces to conduct work ( Hislop & Axtell 2007). This is an important difference to consider when...on a flexible basis (Kunkle, 2000). Hislop and Axtell (2007) discovered that multiple studies compared the performances of teleworkers to those
2012-03-08
members past and present, including Dr. David Krantz, Dr. Mark Ettenhofer, Dr. Cara Olsen and Dr. Neil Grunberg. Additionally, I want to express my...version of the HPQ, referred to as “the absenteeism and presenteeism questions of the Heath and Work Performance Questionnaire,” (Kessler, et al...were carefully chosen for their reliability in other studies. For instance, the absenteeism and presenteeism questions of the Heath and Work
Thrailkill, Eric A.; Kacelnik, Alex; Porritt, Fay; Bouton, Mark E.
2016-01-01
Dogs trained to search for contraband perform a chain of behavior in which they first search for a target and then make a separate response that indicates to the trainer that they have found one. The dogs often conduct multiple searches without encountering a target and receiving the reinforcer (i.e., no contraband is present). Understanding extinction (i.e., the decline in work rate when reinforcers are no longer encountered) may assist in training dogs to work in conditions where targets are rare. We therefore trained rats on a search-target behavior chain modeled on the search behavior of working dogs. A discriminative stimulus signaled that a search response (e.g., chain pull) led to a second stimulus that set the occasion for a target response (e.g., lever press) that was reinforced by a food pellet. In Experiment 1 training with longer search durations and intermittent (partial) reinforcement of searching (i.e. some trials had no target present) both led to more persistent search responding in extinction. The loss of search behavior in extinction was primarily dependent on the number of non-reinforced searches rather than time searching without reinforcement. In Experiments 2 and 3, delivery of non-contingent reinforcers during extinction increased search persistence provided they had also been presented during training. Thus, results with rats suggest that the persistence of working dog performance (or chained behavior generally) may be improved by training with partial reinforcement of searching and non-contingent reinforcement during both training and work (extinction). PMID:27306694
Hippocampal-prefrontal theta-gamma coupling during performance of a spatial working memory task.
Tamura, Makoto; Spellman, Timothy J; Rosen, Andrew M; Gogos, Joseph A; Gordon, Joshua A
2017-12-19
Cross-frequency coupling supports the organization of brain rhythms and is present during a range of cognitive functions. However, little is known about whether and how long-range cross-frequency coupling across distant brain regions subserves working memory. Here we report that theta-slow gamma coupling between the hippocampus and medial prefrontal cortex (mPFC) is augmented in a genetic mouse model of cognitive dysfunction. This increased cross-frequency coupling is observed specifically when the mice successfully perform a spatial working memory task. In wild-type mice, increasing task difficulty by introducing a long delay or by optogenetically interfering with encoding, also increases theta-gamma coupling during correct trials. Finally, epochs of high hippocampal theta-prefrontal slow gamma coupling are associated with increased synchronization of neurons within the mPFC. These findings suggest that enhancement of theta-slow gamma coupling reflects a compensatory mechanism to maintain spatial working memory performance in the setting of increased difficulty.
Ávila, Rafaela T; de Paula, Jonas J; Bicalho, Maria A; Moraes, Edgar N; Nicolato, Rodrigo; Malloy-Diniz, Leandro F; Diniz, Breno S
2015-05-01
Previous studies suggest that executive functions influence the performance on visuoconstructional tasks. This study aims to investigate whether the relationship between planning ability and the copy of complex figures is mediated by distinct components of executive functions (i.e., working memory, inhibitory control and cognitive flexibility). We included a 129 older adults with Alzheimer's disease (n=36, AD), mild cognitive impairment (MCI, n=67), and with no evidence of cognitive impairment (controls, n=26). We evaluated the mediation effect of planning abilities, working memory, cognitive flexibility and inhibitory control on visuoconstructional tasks using a multiple mediation models. We found a significant direct effect of planning on visuoconstructional abilities and a partial mediation effect of working memory and cognitive flexibility on visuoconstructional abilities. The present results indicate that the performance on visuoconstructional task is mediated by multiple interrelated executive functions components, in particular working memory and cognitive flexibility.
A facilitative effect of negative affective valence on working memory.
Gotoh, Fumiko; Kikuchi, Tadashi; Olofsson, Ulrich
2010-06-01
Previous studies have shown that negatively valenced information impaired working memory performance due to an attention-capturing effect. The present study examined whether negative valence could also facilitate working memory. Affective words (negative, neutral, positive) were used as retro-cues in a working memory task that required participants to remember colors at different spatial locations on a computer screen. Following the cue, a target detection task was used to either shift attention to a different location or keep attention at the same location as the retro-cue. Finally, participants were required to discriminate the cued color from a set of distractors. It was found that negative cues yielded shorter response times (RTs) in the attention-shift condition and longer RTs in the attention-stay condition, compared with neutral and positive cues. The results suggest that negative affective valence may enhance working memory performance (RTs), provided that attention can be disengaged.
Brooks, Samantha J; O'Daly, Owen G; Uher, Rudolf; Schiöth, Helgi B; Treasure, Janet; Campbell, Iain C
2012-06-01
Prefrontal cortex (PFC) is dysregulated in women with restricting anorexia nervosa (RAN). It is not known whether appetitive non-conscious stimuli bias cognitive responses in those with RAN. Thirteen women with RAN and 20 healthy controls (HC) completed a dorsolateral PFC (DLPFC) working memory task and an anterior cingulate cortex (ACC) conflict task, while masked subliminal food, aversive and neutral images were presented. During the DLPFC task, accuracy was higher in the RAN compared to the HC group, but superior performance was compromised when subliminal food stimuli were presented: errors positively correlated with self-reported trait anxiety in the RAN group. These effects were not observed in the ACC task. Appetitive activation is intact and anxiogenic in women with RAN, and non-consciously interacts with working memory processes associated with the DLPFC. This interaction mechanism may underlie cognitive inhibition of appetitive processes that are anxiety inducing, in people with AN. Copyright © 2012 Elsevier Inc. All rights reserved.
High-speed and high-fidelity system and method for collecting network traffic
Weigle, Eric H [Los Alamos, NM
2010-08-24
A system is provided for the high-speed and high-fidelity collection of network traffic. The system can collect traffic at gigabit-per-second (Gbps) speeds, scale to terabit-per-second (Tbps) speeds, and support additional functions such as real-time network intrusion detection. The present system uses a dedicated operating system for traffic collection to maximize efficiency, scalability, and performance. A scalable infrastructure and apparatus for the present system is provided by splitting the work performed on one host onto multiple hosts. The present system simultaneously addresses the issues of scalability, performance, cost, and adaptability with respect to network monitoring, collection, and other network tasks. In addition to high-speed and high-fidelity network collection, the present system provides a flexible infrastructure to perform virtually any function at high speeds such as real-time network intrusion detection and wide-area network emulation for research purposes.
ERIC Educational Resources Information Center
Bianchi, June
2008-01-01
The article presents the rationale, methodology, and selected outcomes from "More than a body's work," a collaborative, international, arts educational interactive research project. The project, taking place in both New York and England, explored the ways in which young people construct and "perform" identity through the…
Interference Control, Working Memory Capacity, and Cognitive Abilities: A Latent Variable Analysis
ERIC Educational Resources Information Center
Unsworth, Nash
2010-01-01
The present study examined whether various indices of interference control were related to one another and to other cognitive abilities. It was found that the interference control measures were weakly correlated and could form a single factor that was related to overall memory performance on the tasks as well as to measures of working memory…
ERIC Educational Resources Information Center
Thoma, Michael
2017-01-01
This paper presents an approach to the critical analysis of textbook knowledge, which, working from a discourse theory perspective (based on the work of Foucault), refers to the performative nature of language. The critical potential of the approach derives from an analysis of knowledge-generating logics, which produce particular images of reality…
The Trajectory of Mathematics Skills and Working Memory Thresholds in Girls with Fragile X Syndrome
ERIC Educational Resources Information Center
Murphy, Melissa M.; Mazzocco, Michele M. M.
2009-01-01
Fragile X syndrome is a common genetic disorder associated with executive function deficits and poor mathematics achievement. In the present study, we examined changes in math performance during the elementary and middle school years in girls with fragile X syndrome, changes in the working memory loads under which children could complete a…
Skylab Experiments, Volume 7, Living and Working in Space.
ERIC Educational Resources Information Center
National Aeronautics and Space Administration, Washington, DC.
Basic knowledge about Skylab experiments is presented in this book for the purpose of informing high school teachers about scientific research performed in orbit and enabling the teachers to broaden their scope of material selection. The seventh volume deals with the ability of the Skylab crew to live and work effectively in space. The content is…
Investigating University Educators' Design Thinking and the Implications for Design Support Tools
ERIC Educational Resources Information Center
Bennett, Sue; Agostinho, Shirley; Lockyer, Lori
2016-01-01
All university educators perform design work as they prepare and plan learning experiences for their students. How such design work is undertaken, conceptualised, and optimally supported is the focus of ongoing research for the authors. The purpose of this article is to present the results of a research study that sought to gain a richer…
NASA Technical Reports Server (NTRS)
1992-01-01
The work performed in the previous six months can be divided into three main cases: (1) transmission of images over local area networks (LAN's); (2) coding of color mapped (pseudo-color) images; and (3) low rate video coding. A brief overview of the work done in the first two areas is presented. The third item is reported in somewhat more detail.
Why the Language of Work Is Not Our Best Model
ERIC Educational Resources Information Center
Newbold, Patricia L.
2011-01-01
As Danny G. Langdon wrote in September 2010, for human performance technology to be a science, it needs commonly understood and applied models. He proposed his language of work (LOW) model. This article presents arguments for a very different model, one that cuts the cord to our profession's beginnings in the design of programmed instruction,…
Dimension scaling effects on the yield sensitivity of HEMT digital circuits
NASA Technical Reports Server (NTRS)
Sarker, Jogendra C.; Purviance, John E.
1992-01-01
In our previous works, using a graphical tool, yield factor histograms, we studied the yield sensitivity of High Electron Mobility Transistors (HEMT) and HEMT circuit performance with the variation of process parameters. This work studies the scaling effects of process parameters on yield sensitivity of HEMT digital circuits. The results from two HEMT circuits are presented.
ERIC Educational Resources Information Center
Jones, Gary; Gobet, Fernand; Pine, Julian M.
2008-01-01
Increasing working memory (WM) capacity is often cited as a major influence on children's development and yet WM capacity is difficult to examine independently of long-term knowledge. A computational model of children's nonword repetition (NWR) performance is presented that independently manipulates long-term knowledge and WM capacity to determine…
Richter, Kim Merle; Mödden, Claudia; Eling, Paul; Hildebrandt, Helmut
2018-04-26
To show the effectiveness of a combined recognition and working memory training on everyday memory performance in patients suffering from organic memory disorders. In this double-blind, randomized controlled Study 36 patients with organic memory impairments, mainly attributable to stroke, were assigned to either the experimental or the active control group. In the experimental group a working memory training was combined with a recollection training based on the repetition-lag procedure. Patients in the active control group received the memory therapy usually provided in the rehabilitation center. Both groups received nine hours of therapy. Prior (T0) and subsequent (T1) to the therapy, patients were evaluated on an everyday memory test (EMT) as well as on a neuropsychological test battery. Based on factor analysis of the neuropsychological test scores at T0 we calculated composite scores for working memory, verbal learning and word fluency. After treatment, the intervention group showed a significantly greater improvement for WM performance compared with the active control group. More importantly, performance on the EMT also improved significantly in patients receiving the recollection and working memory training compared with patients with standard memory training. Our results show that combining working memory and recollection training significantly improves performance on everyday memory tasks, demonstrating far transfer effects. The present study argues in favor of a process-based approach for treating memory impairments. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Effects of working memory load and repeated scenario exposure on emergency braking performance.
Engström, Johan; Aust, Mikael Ljung; Viström, Matias
2010-10-01
The objective of the present study was to examine the effect of working memory load on drivers' responses to a suddenly braking lead vehicle and whether this effect (if any) is moderated by repeated scenario exposure. Several experimental studies have found delayed braking responses to lead vehicle braking events during concurrent performance of nonvisual, working memory-loading tasks, such as hands-free phone conversation. However, the common use of repeated, and hence somewhat expected, braking events may undermine the generalizability of these results to naturalistic, unexpected, emergency braking scenarios. A critical lead vehicle braking scenario was implemented in a fixed-based simulator.The effects of working memory load and repeated scenario exposure on braking performance were examined. Brake response time was decomposed into accelerator pedal release time and accelerator-to-brake pedal movement time. Accelerator pedal release times were strongly reduced with repeated scenario exposure and were delayed by working memory load with a small but significant amount (178 ms).The two factors did not interact. There were no effects on accelerator-to-brake pedal movement time. The results suggest that effects of working memory load on response performance obtained from repeated critical lead vehicle braking scenarios may be validly generalized to real world unexpected events. The results have important implications for the interpretation of braking performance in experimental settings, in particular in the context of safety-related evaluation of in-vehicle information and communication technologies.
NASA Technical Reports Server (NTRS)
Vosteen, L. F. (Compiler); Johnson, N. J. (Compiler); Teichman, L. A. (Compiler)
1984-01-01
Papers and working group summaries are presented which address composite material behavior and performance improvement. Topic areas include composite fracture toughness and impact characterization, constituent properties and interrelationships, and matrix synthesis and characterization.
ERIC Educational Resources Information Center
Vuontela, Virve; Carlson, Synnove; Troberg, Anna-Maria; Fontell, Tuija; Simola, Petteri; Saarinen, Suvi; Aronen, Eeva T.
2013-01-01
The present study investigated the development of executive functions (EFs) and their associations with performance and behavior at school in 8-12-year-old children. The EFs were measured by computer-based n-back, Continuous Performance and Go/Nogo tasks. School performance was evaluated by Teacher Report Form (TRF) and behavior by TRF and Child…
Thermal Spray Maps: Material Genomics of Processing Technologies
NASA Astrophysics Data System (ADS)
Ang, Andrew Siao Ming; Sanpo, Noppakun; Sesso, Mitchell L.; Kim, Sun Yung; Berndt, Christopher C.
2013-10-01
There is currently no method whereby material properties of thermal spray coatings may be predicted from fundamental processing inputs such as temperature-velocity correlations. The first step in such an important understanding would involve establishing a foundation that consolidates the thermal spray literature so that known relationships could be documented and any trends identified. This paper presents a method to classify and reorder thermal spray data so that relationships and correlations between competing processes and materials can be identified. Extensive data mining of published experimental work was performed to create thermal spray property-performance maps, known as "TS maps" in this work. Six TS maps will be presented. The maps are based on coating characteristics of major importance; i.e., porosity, microhardness, adhesion strength, and the elastic modulus of thermal spray coatings.
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.
Sandbakk, Øyvind; Hegge, Ann Magdalen; Ettema, Gertjan
2013-01-01
The ability to efficiently utilize metabolic energy to produce work is a key factor for endurance performance. The present study investigated the effects of incline, performance level, and gender on the gross mechanical efficiency during roller ski skating. Thirty-one male and nineteen female elite cross-country skiers performed a 5-min submaximal session at approximately 75% of VO2peak on a 5% inclined treadmill using the G3 skating technique. Thereafter, a 5-min session on a 12% incline using the G2 skating technique was performed at a similar work rate. Gross efficiency was calculated as the external work rate against rolling friction and gravity divided by the metabolic rate using gas exchange. Performance level was determined by the amount of skating FIS points [the Federation of International Skiing (FIS) approved scoring system for ski racing] where fewer points indicate a higher performance level. Strong significant correlations between work rate and metabolic rate within both inclines and gender were revealed (r = −0.89 to 0.98 and P < 0.05 in all cases). Gross efficiency was higher at the steeper incline, both for men (17.1 ± 0.4 vs. 15.8 ± 0.5%, P < 0.05) and women (16.9 ± 0.5 vs. 15.7 ± 0.4%, P < 0.05), but without any gender differences being apparent. Significant correlations between gross efficiency and performance level were found for both inclines and genders (r = −0.65 to 0.81 and P < 0.05 in all cases). The current study demonstrated that cross-country skiers of both genders used less metabolic energy to perform the same amount of work at steeper inclines, and that the better ranked elite male and female skiers skied more efficiently. PMID:24155722
Sandbakk, Oyvind; Hegge, Ann Magdalen; Ettema, Gertjan
2013-01-01
The ability to efficiently utilize metabolic energy to produce work is a key factor for endurance performance. The present study investigated the effects of incline, performance level, and gender on the gross mechanical efficiency during roller ski skating. Thirty-one male and nineteen female elite cross-country skiers performed a 5-min submaximal session at approximately 75% of VO2peak on a 5% inclined treadmill using the G3 skating technique. Thereafter, a 5-min session on a 12% incline using the G2 skating technique was performed at a similar work rate. Gross efficiency was calculated as the external work rate against rolling friction and gravity divided by the metabolic rate using gas exchange. Performance level was determined by the amount of skating FIS points [the Federation of International Skiing (FIS) approved scoring system for ski racing] where fewer points indicate a higher performance level. Strong significant correlations between work rate and metabolic rate within both inclines and gender were revealed (r = -0.89 to 0.98 and P < 0.05 in all cases). Gross efficiency was higher at the steeper incline, both for men (17.1 ± 0.4 vs. 15.8 ± 0.5%, P < 0.05) and women (16.9 ± 0.5 vs. 15.7 ± 0.4%, P < 0.05), but without any gender differences being apparent. Significant correlations between gross efficiency and performance level were found for both inclines and genders (r = -0.65 to 0.81 and P < 0.05 in all cases). The current study demonstrated that cross-country skiers of both genders used less metabolic energy to perform the same amount of work at steeper inclines, and that the better ranked elite male and female skiers skied more efficiently.
Coordinating the Design and Management of Heterogeneous Datacenter Resources
ERIC Educational Resources Information Center
Guevara, Marisabel
2014-01-01
Heterogeneous design presents an opportunity to improve energy efficiency but raises a challenge in management. Whereas prior work separates the two, we coordinate heterogeneous design and management. We present a market-based resource allocation mechanism that navigates the performance and power trade-offs of heterogeneous architectures. Given…
ERIC Educational Resources Information Center
Baumgartner, Erin
2004-01-01
Poster presentations are one way scientists present their latest research findings at professional meetings. This format also works well in the classroom and gives students the opportunity to communicate the results of their experiments (perhaps the most critical portion of their studies). In a performance-based task such as a poster session,…
Integrating Person and Situation Perspectives on Work Satisfaction: A Social-Cognitive View
ERIC Educational Resources Information Center
Lent, Robert W.; Brown, Steven D.
2006-01-01
Social cognitive career theory (Lent, Brown, & Hackett, 1994) was originally designed to help explain interest development, choice, and performance in career and educational domains. These three aspects of career/academic development were presented in distinct but overlapping segmental models. This article presents a fourth social cognitive model…
Grot, Stéphanie; Légaré, Virginie Petel; Lipp, Olivier; Soulières, Isabelle; Dolcos, Florin; Luck, David
2017-10-01
Working memory deficits have been widely reported in schizophrenia, and may result from inefficient binding processes. These processes, and their neural correlates, remain understudied in schizophrenia. Thus, we designed an FMRI study aimed at investigating the neural correlates of both passive and active binding in working memory in schizophrenia. Nineteen patients with schizophrenia and 23 matched controls were recruited to perform a working memory binding task, in which they were instructed to memorize three letters and three spatial locations. In the passive binding condition, letters and spatial locations were directly presented as bound. Conversely, in the active binding condition, words and spatial locations were presented as separated, and participants were instructed to intentionally create associations between them. Patients exhibited a similar performance to the controls for the passive binding condition, but a significantly lower performance for the active binding. FMRI analyses revealed that this active binding deficit was related to aberrant activity in the posterior parietal cortex and the ventrolateral prefrontal cortex. This study provides initial evidence of a specific deficit for actively binding information in schizophrenia, which is linked to dysfunctions in the neural networks underlying attention, manipulation of information, and encoding strategies. Together, our results suggest that all these dysfunctions may be targets for neuromodulation interventions known to improve cognitive deficits in schizophrenia. Copyright © 2017 Elsevier B.V. All rights reserved.
Phonological awareness and the working memory of children with and without literacy difficulties.
Cardoso, Andreia Martins de Souza; Silva, Mônica Marins da; Pereira, Mônica Medeiros de Britto
2013-01-01
To investigate phonological awareness and working memory skills as well as their influence on the literacy process in a group of intellectually normal children. Forty intellectually normal children (7.6-8.0 years) from the second and third grades of elementary school participated. Children were organized in two groups (20 children each): one with and another without literacy difficulties. These participants underwent RAVEN's intelligence quotient test, audiometric assessment, CONFIAS test of phonological awareness, written spelling task, and working memory test. Children in the alphabetic phase presented a good development of phonological awareness, and 85% of them showed a high-performance working memory. Children in the syllabic-alphabetic phase had changes in phonological awareness, and 91.6% of them showed an average working memory performance. The subjects at pre-syllabic and syllabic phases demonstrated more difficulties in phonological awareness than those at syllabic-alphabetic and had a poor working memory performance. Between-group differences were observed for CONFIAS and working memory tests (p<0.0001). There was also a significant correlation (r=0.78, p=0.01) between the skills of phonological awareness and working memory for the total sample of individuals. Based on these results, it was found that as phonological awareness and working memory levels increased, the literacy phase also advanced, therefore showing that these are directly proportional measures.
Temporal Constraints of the Word Blindness Posthypnotic Suggestion on Stroop Task Performance
ERIC Educational Resources Information Center
Parris, Benjamin A.; Dienes, Zoltan; Hodgson, Timothy L.
2012-01-01
The present work investigated possible temporal constraints on the posthypnotic word blindness suggestion effect. In a completely within-subjects and counterbalanced design 19 highly suggestible individuals performed the Stroop task both with and without a posthypnotic suggestion that they would be unable to read the word dimension of the Stroop…
ERIC Educational Resources Information Center
Espinoza, Penelope P.; Quezada, Stephanie A.; Rincones, Rodolfo; Strobach, E. Natalia; Gutierrez, Maria Armida Estrada
2012-01-01
The present work investigates the validation of a newly developed instrument, the attributional bias instrument, based on achievement attribution theories that distinguish between effort and ability explanations of behavior. The instrument further incorporates the distinction between explanations for success versus failure in academic performance.…
Sabotage or Performed Compliance: Rhetorics of Resistance in Temp Worker Discourse
ERIC Educational Resources Information Center
Jordan, John W.
2003-01-01
This essay analyzes contemporary temporary employment texts and the competing rhetorical definitions that shape the meanings of employment and identity in the contingent economy. Arguing against resistant labor rhetoric that is ill-suited to present conditions of temp work, the author locates and advocates a rhetoric of "performativity" that…
Safety in bear country: protective measures and bullet performance at short range.
W.R. Meehan; J.F. Thilenius
1983-01-01
Bears are frequently encountered by people working in or enjoying the outdoors. Some government agencies have regulations concerning the firearms their personnel carry for protection against bears.Guidelines to prevent hazardous encounters with bears are presented, and the performance of commonly used weapons and ammunition is discussed. The ballistic...
Overview: Performance Adaptive Aeroelastic Wing
NASA Technical Reports Server (NTRS)
Hashemi, Kelley
2017-01-01
An overview of recent aeroelasitc wing-shaping work at the NASA Ames Research Center is presented. The highlight focuses on activity related to the Performance Adaptive Aeroelastic Wing concept and related Variable Camber Continuous Trailing Edge Flap actuation system. Topics covered include drag-reducing configurations and online algorithms, gust and maneuver load techniques, and wind tunnel demonstrations.
SCPS-TP: A Satellite-Enhanced TCP
NASA Technical Reports Server (NTRS)
Scott, Keith; Torgerson, Leigh
2004-01-01
This viewgraph presentation reviews the Space Communications Protocol Standard Transport Protocol (SCPS-TP) which is a satellite enhanced Transport Control Protocol (TCP). The contents include: 1) Purpose; 2) Background; 3) Stressed Communication Environments; 4) SCPS-TP Features; 5) SCPS-TP Performance; 6) Performance Enhancing Proxies (PEPs); and 7) Ongoing and Future SCPS-TP Work.
Restricted and Adaptive Masculine Gender Performance in White Gay College Men
ERIC Educational Resources Information Center
Anderson-Martinez, Richard; Vianden, Jörg
2014-01-01
This article presents the results of a qualitative exploration of the performance of masculine gender identities in six gay male students enrolled at a master's comprehensive public institution in the Midwest. This article builds on the work of Laker and Davis (2011) and Rankin (2005). The findings indicate participants adapted their gender…
Individual Differences in Visual Word Recognition: Insights from the English Lexicon Project
ERIC Educational Resources Information Center
Yap, Melvin J.; Balota, David A.; Sibley, Daragh E.; Ratcliff, Roger
2012-01-01
Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences among individuals who contributed to the English…
Fountain-Zaragoza, Stephanie; Londerée, Allison; Whitmoyer, Patrick; Prakash, Ruchika Shaurya
2016-08-01
Age-related cognitive decline brings decreases in functional status. Dispositional mindfulness, the tendency towards present-moment attention, is hypothesized to correspond with enhanced attention, whereas mind-wandering may be detrimental to cognition. The relationships among mindfulness, task-related and task-unrelated thought, and attentional control performance on Go/No-Go and Continuous Performance tasks were examined in older adults. Dispositional mindfulness was negatively associated with task-unrelated thought and was positively associated with reactive control, but not proactive control or Go/No-Go performance. Although mind-wandering was not directly associated with performance, task-unrelated thought mediated the mindfulness-proactive control relation. Fewer task-unrelated thoughts were associated with lower proactive control. Interestingly, this effect was moderated by working memory such that it was present for those with low-average, but not high, working memory. This study highlights the importance of dispositional mindfulness and mind-wandering propensity in accounting for individual differences in attentional control in older adults, providing important targets for future cognitive remediation interventions. Copyright © 2016 Elsevier Inc. All rights reserved.
Feasibility of MHD submarine propulsion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doss, E.D.; Sikes, W.C.
1992-09-01
This report describes the work performed during Phase 1 and Phase 2 of the collaborative research program established between Argonne National Laboratory (ANL) and Newport News Shipbuilding and Dry Dock Company (NNS). Phase I of the program focused on the development of computer models for Magnetohydrodynamic (MHD) propulsion. Phase 2 focused on the experimental validation of the thruster performance models and the identification, through testing, of any phenomena which may impact the attractiveness of this propulsion system for shipboard applications. The report discusses in detail the work performed in Phase 2 of the program. In Phase 2, a two Teslamore » test facility was designed, built, and operated. The facility test loop, its components, and their design are presented. The test matrix and its rationale are discussed. Representative experimental results of the test program are presented, and are compared to computer model predictions. In general, the results of the tests and their comparison with the predictions indicate that thephenomena affecting the performance of MHD seawater thrusters are well understood and can be accurately predicted with the developed thruster computer models.« less
La Fata, Concetta Manuela; Lupo, Toni; Piazza, Tommaso
2017-11-21
A novel fuzzy-based approach which combines ELECTRE III along with the Importance-Performance Analysis (IPA) is proposed in the present work to comparatively evaluate the service quality in the public healthcare context. Specifically, ELECTRE III is firstly considered to compare the service performance of examined hospitals in a noncompensatory manner. Afterwards, IPA is employed to support the service quality management to point out improvement needs and their priorities. The proposed approach also incorporates features of the Fuzzy Set Theory so as to address the possible uncertainty, subjectivity and vagueness of involved experts in evaluating the service quality. The model is applied to five major Sicilian public hospitals, and strengths and criticalities of the delivered service are finally highlighted and discussed. Although several approaches combining multi-criteria methods have already been proposed in the literature to evaluate the service performance in the healthcare field, to the best of the authors' knowledge the present work represents the first attempt at comparing service performance of alternatives in a noncompensatory manner in the investigated context.
Koshino, Hideya
2017-01-01
Working memory and attention are closely related. Recent research has shown that working memory can be viewed as internally directed attention. Working memory can affect attention in at least two ways. One is the effect of working memory load on attention, and the other is the effect of working memory contents on attention. In the present study, an interaction between working memory contents and perceptual load in distractor processing was investigated. Participants performed a perceptual load task in a standard form in one condition (Single task). In the other condition, a response-related distractor was maintained in working memory, rather than presented in the same stimulus display as a target (Dual task). For the Dual task condition, a significant compatibility effect was found under high perceptual load; however, there was no compatibility effect under low perceptual load. These results suggest that the way the contents of working memory affect visual search depends on perceptual load. Copyright © 2016 Elsevier B.V. All rights reserved.
Implicit motives, explicit traits, and task and contextual performance at work.
Lang, Jonas W B; Zettler, Ingo; Ewen, Christian; Hülsheger, Ute R
2012-11-01
Personality psychologists have long argued that explicit traits (as measured by questionnaires) channel the expression of implicit motives (as measured by coding imaginative verbal behavior) such that both interact in the prediction of relevant life outcome variables. In the present research, we apply these ideas in the context of industrial and organizational psychology and propose that 2 explicit traits work as channels for the expression of 3 core implicit motives in task and contextual job performance (extraversion for implicit affiliation and implicit power; explicit achievement for implicit achievement). As a test of these theoretical ideas, we report a study in which employees (N = 241) filled out a questionnaire booklet and worked on an improved modern implicit motive measure, the operant motive test. Their supervisors rated their task and contextual performance. Results support 4 of the 6 theoretical predictions and show that interactions between implicit motives and explicit traits increase the explained criterion variance in both task and contextual performance. (c) 2012 APA, all rights reserved.
[Phonological awareness, working memory, reading and writing performances in familial dyslexia].
Capellini, Simone Aparecida; Padula, Niura Aparecida de Mouro Ribeiro; Santos, Lara Cristina Antunes Dos; Lourenceti, Maria Dalva; Carrenho, Erika Hasse; Ribeiro, Lucilene Arilho
2007-01-01
familial dyslexia. to characterize and compare the phonological awareness, working memory, reading and writing abilities of individuals whose family members are also affected. in this study 10 familial nuclei of natural family relationship of individuals with dyslexia were analyzed. Families of natural individuals living in the west region of the state of São Paulo were selected. Inclusion criteria were: to be a native speaker of the Brazilian Portuguese language, to have 8 years of age or more, to present positive familial history for learning disabilities, that is, to present at least one relative with difficulties in learning. Exclusion criteria were: to present any neurological disorder genetically caused or not, in any of the family members, such as dystonia, extra pyramidal diseases, mental disorder, epilepsy, attention deficit and hyperactivity disorder (ADHA); psychiatric symptoms or conditions; or any other pertinent conditions that could cause errors in the diagnosis. As for the diagnosis of developmental dyslexia, information about the familial history of the adolescents and children was gathered with the parents, so that a detailed pedigree could be delineated. Neurological, psychological, speech-language, and school performance evaluations were made with the individuals and their families. the results of this study suggest that the dyslexic individuals and their respective relatives, also with dyslexia, presented lower performances than the control group in terms of rapid automatic naming, reading, writing and phonological awareness. deficits in phonological awareness, working memory, reading and writing seem to have genetic susceptibility that possibly determine, when in interaction with the environment, the manifestation of dyslexia.
Material science as basis for nuclear medicine: Holmium irradiation for radioisotopes production
NASA Astrophysics Data System (ADS)
Usman, Ahmed Rufai; Khandaker, Mayeen Uddin; Haba, Hiromitsu; Otuka, Naohiko
2018-05-01
Material Science, being an interdisciplinary field, plays important roles in nuclear science. These applications are seen in weaponry, armoured vehicles, accelerator structure and development, semiconductor detectors, nuclear medicine and many more. Present study presents the applications of some metals in nuclear medicine (radioisotope production). The charged-particle-induced nuclear reactions by using cyclotrons or accelerators have become a very vital feature of the modern nuclear medicine. Realising the importance of excitation functions for the efficient production of medical radionuclides, some very high purity holmium metals are generally prepared or purchased for bombardment in nuclear accelerators. In the present work, various methods to obtain pure holmium for radioisotope production have been discussed while also presenting details of our present studies. From the experimental work of the present studies, some very high purity holmium foils have been used in the work for a comprehensive study of residual radionuclides production cross-sections. The study was performed using a stacked-foil activation technique combined with γ-ray spectrometry. The stack was bombarded with 50.4 MeV alpha particle beam from AVF cyclotron of RI Beam Factory, Nishina Centre for Accelerator-Based Science, RIKEN, Japan. The work produced thulium radionuclides useful in nuclear medicine.
Running with emotion: when affective content hampers working memory performance.
Fairfield, Beth; Mammarella, Nicola; Di Domenico, Alberto; Palumbo, Rocco
2015-03-01
This study tested the hypothesis that affective content may undermine rather than facilitate working memory (WM) performance. To this end, participants performed a running WM task with positive, negative and neutral words. In typical running memory tasks, participants are presented with lists of unpredictable length and are asked to recall the last three or four items. We found that accuracy with affective words decreased as lists lengthened, whereas list length did not influence recall of neutral words. We interpreted this pattern of results in terms of a limited resource model of WM in which valence represents additional information that needs to be manipulated, especially in the context of difficult trials. © 2014 International Union of Psychological Science.
Greenstein, Justin E; Kassel, Jon D; Wardle, Margaret C; Veilleux, Jennifer C; Evatt, Daniel P; Heinz, Adrienne J; Roesch, Linda L; Braun, Ashley R; Yates, Marisa C
2010-04-01
Research indicates that nicotine and alcohol are often used on the same occasion. However, the reasons for their concurrent use are not well understood. We hypothesized that one reason smokers use tobacco when they drink alcohol is to compensate for alcohol's negative effects on processing capacity with nicotine's enhancement of processing capacity. As such, the present study tested this theory by using an independent groups design to examine the separate and combined acute effects of alcohol and nicotine on working memory (WM) capacity. Nonabstinent daily smokers (n = 127) performed the counting span task (CSPAN) after consuming either an alcohol (men: 0.8 g/kg; women: 0.7 g/kg) or placebo beverage and smoking either nicotinized (1.14 mg nicotine, 15.9 mg tar) or denicotinized (.06 mg nicotine, 17.9 mg tar) cigarettes. Analyses revealed that smokers who smoked the nicotinized cigarettes performed significantly worse on the CSPAN task than smokers who smoked the denicotinized cigarettes. Although there was no main effect of alcohol on WM performance, women exhibited better WM performance than men after consuming alcohol whereas men performed better than women on the WM task after consuming the placebo beverage. Findings also revealed no interaction between the two substances on WM performance. Taken together, results suggest that nicotine impairs nonabstinent smokers' verbal WM capacity and that gender moderates the effects of alcohol on WM. Furthermore, the present findings failed to support the notion that nicotine compensates for alcohol-related decrements in working memory capacity. 2010 APA, all rights reserved
Clinical efficacy of electronic apex locators: systematic review.
Martins, Jorge N R; Marques, Duarte; Mata, António; Caramês, João
2014-06-01
Apical constriction has been proposed as the most appropriate apical limit for the endodontic working length. Despite being the most used, some limitations are attributed to the radiographic method of working length determination. It lacks precision because it is based on the average position of the apical constriction. The electronic apex locators have been presented as an alternative to the odontometry performed by radiography. These devices detect the transition of the pulp to the periodontal tissue, which is anatomically very close to the apical constriction and may perform with improved accuracy. A systematic review was performed to compare the radiographic and electronic methods. Clinical studies that compared both methods were searched for on 7 electronic databases, a manual search was performed on the bibliography of articles collected on the electronic databases, and the authors were contacted to ask for references of more research not detected on the electronic and manual search. Twenty-one articles were selected. The majority were comparative or evaluation studies, and very few clinical studies comparing both methods are available. Several methodological limitations are present on the collected articles and debated in this review. Although the available scientific evidence base is short and at considerable risk of bias, it is still possible to conclude that the apical locator reduces the patient radiation exposure and also that the electronic method may perform better on the working length determination. At least one radiographic control should be performed to detect possible errors of the electronic devices. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Stanton, Neville A; Bessell, Kevin
2014-01-01
This paper presents the application of Cognitive Work Analysis to the description of the functions, situations, activities, decisions, strategies, and competencies of a Trafalgar class submarine when performing the function of returning to periscope depth. All five phases of Cognitive Work Analysis are presented, namely: Work Domain Analysis, Control Task Analysis, Strategies Analysis, Social Organisation and Cooperation Analysis, and Worker Competencies Analysis. Complex socio-technical systems are difficult to analyse but Cognitive Work Analysis offers an integrated way of analysing complex systems with the core of functional means-ends analysis underlying all of the other representations. The joined-up analysis offers a coherent framework for understanding how socio-technical systems work. Data were collected through observation and interviews at different sites across the UK. The resultant representations present a statement of how the work domain and current activities are configured in this complex socio-technical system. This is intended to provide a baseline, from which all future conceptions of the domain may be compared. The strength of the analysis is in the multiple representations from which the constraints acting on the work may be analysed. Future research needs to challenge the assumptions behind these constraints in order to develop new ways of working. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Berryhill, Marian E; Richmond, Lauren L; Shay, Cara S; Olson, Ingrid R
2012-01-01
It is well known that visual working memory (VWM) performance is modulated by attentional cues presented during encoding. Interestingly, retrospective cues presented after encoding, but prior to the test phase also improve performance. This improvement in performance is termed the retro-cue benefit. We investigated whether the retro-cue benefit is sensitive to cue type, whether participants were aware of their improvement in performance due to the retro-cue, and whether the effect was under strategic control. Experiment 1 compared the potential cueing benefits of abrupt onset retro-cues relying on bottom-up attention, number retro-cues relying on top-down attention, and arrow retro-cues, relying on a mixture of both. We found a significant retro-cue effect only for arrow retro-cues. In Experiment 2, we tested participants' awareness of their use of the informative retro-cue and found that they were aware of their improved performance. In Experiment 3, we asked whether participants have strategic control over the retro-cue. The retro-cue was difficult to ignore, suggesting that strategic control is low. The retro-cue effect appears to be within conscious awareness but not under full strategic control.
2013-05-17
wide range of clinical presentations from mild to life threatening. We present a case of a 34 year old woman in the Burn Intensive Care Unit , who...P., Lundy J. B., Renz E. M., Chung K. K., 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS...ES) United States Army Institute of Surgical Research, JBSA Fort Sam Houston, TX 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING
Betsou, Fay; Bulla, Alexandre; Cho, Sang Yun; Clements, Judith; Chuaqui, Rodrigo; Coppola, Domenico; De Souza, Yvonne; De Wilde, Annemieke; Grizzle, William; Guadagni, Fiorella; Gunter, Elaine; Heil, Stacey; Hodgkinson, Verity; Kessler, Joseph; Kiehntopf, Michael; Kim, Hee Sung; Koppandi, Iren; Shea, Katheryn; Singh, Rajeev; Sobel, Marc; Somiari, Stella; Spyropoulos, Demetri; Stone, Mars; Tybring, Gunnel; Valyi-Nagy, Klara; Van den Eynden, Gert; Wadhwa, Lalita
2016-10-01
This technical report presents quality control (QC) assays that can be performed in order to qualify clinical biospecimens that have been biobanked for use in research. Some QC assays are specific to a disease area. Some QC assays are specific to a particular downstream analytical platform. When such a qualification is not possible, QC assays are presented that can be performed to stratify clinical biospecimens according to their biomolecular quality.
NASA Technical Reports Server (NTRS)
Rice, James E.
1996-01-01
The report is organized into sections representing the phases of work performed in analyzing the STS-73 (USML-2) results. Section 1 briefly outlines the Orbital Acceleration Research Experiment (OARE), system features, coordinates, and measurement parameters. Section 2 describes the results from STS-73. The mission description, data calibration, and representative data obtained on STS-73 are presented. Also, the anomalous performance of OARE on STS-73 is discussed. Finally, Section 3 presents a discussion of accuracy achieved and achievable with OARE.
OARE STS-75 (USMP-3) Final Report
NASA Technical Reports Server (NTRS)
Rice, James E.
1996-01-01
The report is organized into sections representing the phases of work performed in analyzing the STS-75 (USMP-3) results. Section 1 briefly outlines the Orbital Acceleration Research Experiment (OARE) system features, coordinates, and measurement parameters. Section 2 describes the results from STS-75. The mission description, data calibration, and representative data obtained on STS-75 are presented. Also, the anomalous performance of OARE on STS-75 is discussed. Finally, Section 3 presents a discussion of accuracy achieved and achievable with OARE.
Bulla, Alexandre; Cho, Sang Yun; Clements, Judith; Chuaqui, Rodrigo; Coppola, Domenico; De Souza, Yvonne; De Wilde, Annemieke; Grizzle, William; Guadagni, Fiorella; Gunter, Elaine; Heil, Stacey; Hodgkinson, Verity; Kessler, Joseph; Kiehntopf, Michael; Kim, Hee Sung; Koppandi, Iren; Shea, Katheryn; Singh, Rajeev; Sobel, Marc; Somiari, Stella; Spyropoulos, Demetri; Stone, Mars; Tybring, Gunnel; Valyi-Nagy, Klara; Van den Eynden, Gert; Wadhwa, Lalita
2016-01-01
This technical report presents quality control (QC) assays that can be performed in order to qualify clinical biospecimens that have been biobanked for use in research. Some QC assays are specific to a disease area. Some QC assays are specific to a particular downstream analytical platform. When such a qualification is not possible, QC assays are presented that can be performed to stratify clinical biospecimens according to their biomolecular quality. PMID:27046294
NASA Technical Reports Server (NTRS)
Holden, K.L.; Boyer, J.L.; Sandor, A.; Thompson, S.G.; McCann, R.S.; Begault, D.R.; Adelstein, B.D.; Beutter, B.R.; Stone, L.S.
2009-01-01
The goal of the Information Presentation Directed Research Project (DRP) is to address design questions related to the presentation of information to the crew. The major areas of work, or subtasks, within this DRP are: 1) Displays, 2) Controls, 3) Electronic Procedures and Fault Management, and 4) Human Performance Modeling. This DRP is a collaborative effort between researchers at Johnson Space Center and Ames Research Center.
Working with Advanced Primary School Students in Physics
NASA Astrophysics Data System (ADS)
Jankovic, Ljiljana; Cucic, Dragoljub
2010-01-01
Working with students who have special needs is the type of work that requires special engagement and skills of those who perform it. Working with gifted children requires outstanding knowledge of a teacher and above all the teachers should be very well informed on the subject they teach, Physics in our case. This work also requires great pedagogical and psychological skills so that these talented students would be approached in a suitable way. In this paper we will present to you our methods of teaching Physics to these talented children (13 years old), in the Regional Center for Talents "Mihajlo Pupin" in Pancevo.
Surgical simulation tasks challenge visual working memory and visual-spatial ability differently.
Schlickum, Marcus; Hedman, Leif; Enochsson, Lars; Henningsohn, Lars; Kjellin, Ann; Felländer-Tsai, Li
2011-04-01
New strategies for selection and training of physicians are emerging. Previous studies have demonstrated a correlation between visual-spatial ability and visual working memory with surgical simulator performance. The aim of this study was to perform a detailed analysis on how these abilities are associated with metrics in simulator performance with different task content. The hypothesis is that the importance of visual-spatial ability and visual working memory varies with different task contents. Twenty-five medical students participated in the study that involved testing visual-spatial ability using the MRT-A test and visual working memory using the RoboMemo computer program. Subjects were also trained and tested for performance in three different surgical simulators. The scores from the psychometric tests and the performance metrics were then correlated using multivariate analysis. MRT-A score correlated significantly with the performance metrics Efficiency of screening (p = 0.006) and Total time (p = 0.01) in the GI Mentor II task and Total score (p = 0.02) in the MIST-VR simulator task. In the Uro Mentor task, both the MRT-A score and the visual working memory 3-D cube test score as presented in the RoboMemo program (p = 0.02) correlated with Total score (p = 0.004). In this study we have shown that some differences exist regarding the impact of visual abilities and task content on simulator performance. When designing future cognitive training programs and testing regimes, one might have to consider that the design must be adjusted in accordance with the specific surgical task to be trained in mind.
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.
Modeling, system identification, and control of ASTREX
NASA Technical Reports Server (NTRS)
Abhyankar, Nandu S.; Ramakrishnan, J.; Byun, K. W.; Das, A.; Cossey, Derek F.; Berg, J.
1993-01-01
The modeling, system identification and controller design aspects of the ASTREX precision space structure are presented in this work. Modeling of ASTREX is performed using NASTRAN, TREETOPS and I-DEAS. The models generated range from simple linear time-invariant models to nonlinear models used for large angle simulations. Identification in both the time and frequency domains are presented. The experimental set up and the results from the identification experiments are included. Finally, controller design for ASTREX is presented. Simulation results using this optimal controller demonstrate the controller performance. Finally the future directions and plans for the facility are addressed.
Thermodynamic analysis of performance improvement by reheat on the CO2 transcritical power cycle
NASA Astrophysics Data System (ADS)
Tuo, Hanfei
2012-06-01
The CO2 transcritical rankine power cycle has been widely investigated recently, because of its better temperature glide matching between sensible heat source and working fluid in vapor generator, and its desirable qualities, such as moderate critical point, little environment impact and low cost. A reheat CO2 transcritical power cycle with two stage expansion is presented to improve baseline cycle performance in this paper. Energy and exergy analysis are carried out to investigate effects of important parameters on cycle performance. The main results show that reheat cycle performance is sensitive to the variation of medium pressures and the optimum medium pressures exist for maximizing work output and thermal efficiency, respectively. Reheat cycle is compared to baseline cycle under the same conditions. More significant improvements by reheat are obtained at lower turbine inlet temperatures and larger high cycle pressure. Work output improvement is much higher than thermal efficiency improvement, because extra waste heat is required to reheat CO2. Based on second law analysis, exergy efficiency of reheat cycle is also higher than that of baseline cycle, because more useful work is converted from waste heat. Reheat with two stage expansion has great potential to improve thermal efficiency and especially net work output of a CO2 transcritical power cycle using a low-grade heat source.
Decision rules for spaceborne operations planning
NASA Technical Reports Server (NTRS)
Smith, Jeffrey H.
1992-01-01
Recent study of Space Station Freedom requirements for extravehicular activity (EVA) to perform external maintenance tasks emphasize an oversubscription of resources for performing on-orbit tasks. Extravehicular robotics (EVR) and cooperative EVA combined with EVR (using crew and robots synergistically to perform tasks) have been suggested as a part of the solution to reduce EVA. The question remains however, 'Under what conditions is it cost-effective to use the EVA and/or EVR resource.' The answer to such a question also has implications for the Space Station Freedom and its external maintenance as well as the Space Exploration Initiative (SEI) where the issue of work-system allocation is magnified by the long distances and scope of EVA work. This paper describes a simple technique of interest to operational planners and robot technology planners for determining in an economic context whether to use EVA alone, EVR alone, or Cooperative EVA. It is also shown that given: (1) the task times for these alternatives; and (2) the marginal costs of EVA, EVR, and IVA, the appropriate work system for performing the task can be identified. The paper illustrates how the work system choice is based on the ratio of costs. An example using Space Station Freedom data is presented to illustrate the trade-offs among alternative work-systems.
Minigalin, A D; Shumakov, A R; Novozhilov, A V; Samsonova, A V; Kos'mina, E A; Kalinskiĭ, M I; Baranova, T I; Kubasov, I V; Morozov, V I
2015-01-01
The aim of this study was to examine the effect of exhaustive weightlifting exercise on electrical and biochemical variables and performance capacity in young male subjects. The onset of exercise (80-50% 1RM) was associated with a decrease in the amount of work performed, which was followed by a steady performance capacity at 40-10% 1RM. There were no significant changes of m. rectus femoris EMG maximal amplitude though it tended to be increased during the first half of exercise. A significant blood lactate concentration increase indicated that an anaerobic metabolism was a predominant mechanism of muscle contraction energy-supply. CK level in blood plasma did not change but plasma myoglobin concentration doubled immediately post-exercise. The data presented here suggest that decrease in performance capacity was likely due to progressive "refusal of work" of the fast motor units and work prolongation of weaker, intermediate and slow motor units. Unchangeable CK activity and relatively small increase in myoglobin concentration in plasma suggest that used weightlifting exercise did not induced substantial damage in myocytes' membranes in our subjects.
Hori, Hajime
2013-10-01
In Japan, working environment measurement is prescribed in the designated workplaces using hazardous materials. Measurements should be carried out periodically and countermeasures are performed depending on the results. By introducing such a system, working environments have remarkably improved. However, in the designated workplaces, measurements should be continued even in work environments found safe. On the other hand, measurement need not be obliged for non-designated workplaces even if hazardous materials are utilized.In the United States of America and many European countries, work environment management and work management are carried out by measuring personal exposure concentrations. In Japan, the Ministry of Health, Labour and Welfare is now discussing the introduction of personal exposure monitoring. However, many problems exist to prevent the simple introduction of American and European methods. This paper describes the brief history, present state and problems of work environment control in Japan, comparing with the systems of American and European countries.
Kline, Julia E.; Poggensee, Katherine; Ferris, Daniel P.
2014-01-01
When humans walk in everyday life, they typically perform a range of cognitive tasks while they are on the move. Past studies examining performance changes in dual cognitive-motor tasks during walking have produced a variety of results. These discrepancies may be related to the type of cognitive task chosen, differences in the walking speeds studied, or lack of controlling for walking speed. The goal of this study was to determine how young, healthy subjects performed a spatial working memory task over a range of walking speeds. We used high-density electroencephalography to determine if electrocortical activity mirrored changes in cognitive performance across speeds. Subjects stood (0.0 m/s) and walked (0.4, 0.8, 1.2, and 1.6 m/s) with and without performing a Brooks spatial working memory task. We hypothesized that performance of the spatial working memory task and the associated electrocortical activity would decrease significantly with walking speed. Across speeds, the spatial working memory task caused subjects to step more widely compared with walking without the task. This is typically a sign that humans are adapting their gait dynamics to increase gait stability. Several cortical areas exhibited power fluctuations time-locked to memory encoding during the cognitive task. In the somatosensory association cortex, alpha power increased prior to stimulus presentation and decreased during memory encoding. There were small significant reductions in theta power in the right superior parietal lobule and the posterior cingulate cortex around memory encoding. However, the subjects did not show a significant change in cognitive task performance or electrocortical activity with walking speed. These findings indicate that in young, healthy subjects walking speed does not affect performance of a spatial working memory task. These subjects can devote adequate cortical resources to spatial cognition when needed, regardless of walking speed. PMID:24847239
NASA Technical Reports Server (NTRS)
Peoples, J. A.
1975-01-01
Report includes many charts that present graphically the effects of design parameters on performance. Equations and data are given which can assist designer in selecting among such factors as working medium, horsepower, and engine components.
Electrical properties of epoxies used in hybrid microelectronics
NASA Technical Reports Server (NTRS)
Stout, C. W.
1976-01-01
The electrical properties and basic characteristics of the structure of conductive epoxies were studied. The results of the experimental work performed to measure the electrical properties of epoxies are presented.
Fiber-Optic Sensing for In-Space Inspection
NASA Technical Reports Server (NTRS)
Pena, Francisco; Richards, W. Lance; Piazza, Anthony; Parker, Allen R.; Hudson, Larry D.
2014-01-01
This presentation provides examples of fiber optic sensing technology development activities performed at NASA Armstrong. Examples of current and previous work that support in-space inspection techniques and methodologies are highlighted.
Role of attentional tags in working memory-driven attentional capture.
Kuo, Chun-Yu; Chao, Hsuan-Fu
2014-08-01
Recent studies have demonstrated that the contents of working memory capture attention when performing a visual search task. However, it remains an intriguing and unresolved question whether all kinds of items stored in working memory capture attention. The present study investigated this issue by manipulating the attentional tags (target or distractor) associated with information maintained in working memory. The results showed that working memory-driven attentional capture is a flexible process, and that attentional tags associated with items stored in working memory do modulate attentional capture. When items were tagged as a target, they automatically captured attention; however, when items were tagged as a distractor, attentional capture was reduced.
Coefficient of performance of Stirling refrigerators
NASA Astrophysics Data System (ADS)
E Mungan, Carl
2017-09-01
Stirling coolers transfer heat in or out of the working fluid during all four stages of their operation, and their coefficient of performance depends on whether the non-isothermal heat exchanges are performed reversibly or irreversibly. Both of these possibilities can in principle be arranged. Notably, if the working fluid is an ideal gas, the input of energy in the form of heat during one isochoric step is equal in magnitude to the output during the other isochoric step in the cycle. The theoretical performance of the fridge can then attain the reversible Carnot limit if a regenerator is used, which is a high heat capacity material through which the gas flows. Various Stirling refrigerator configurations are analysed in this article at a level of presentation suitable for an introductory undergraduate thermodynamics course.
Ng, Elaine Hoi Ning; Rudner, Mary; Lunner, Thomas; Rönnberg, Jerker
2015-01-01
A hearing aid noise reduction (NR) algorithm reduces the adverse effect of competing speech on memory for target speech for individuals with hearing impairment with high working memory capacity. In the present study, we investigated whether the positive effect of NR could be extended to individuals with low working memory capacity, as well as how NR influences recall performance for target native speech when the masker language is non-native. A sentence-final word identification and recall (SWIR) test was administered to 26 experienced hearing aid users. In this test, target spoken native language (Swedish) sentence lists were presented in competing native (Swedish) or foreign (Cantonese) speech with or without binary masking NR algorithm. After each sentence list, free recall of sentence final words was prompted. Working memory capacity was measured using a reading span (RS) test. Recall performance was associated with RS. However, the benefit obtained from NR was not associated with RS. Recall performance was more disrupted by native than foreign speech babble and NR improved recall performance in native but not foreign competing speech. Noise reduction improved memory for speech heard in competing speech for hearing aid users. Memory for native speech was more disrupted by native babble than foreign babble, but the disruptive effect of native speech babble was reduced to that of foreign babble when there was NR.
Morrell, R W; Park, D C
1993-09-01
Older adults may be disadvantaged in the performance of procedural assembly tasks because of age-related declines in working memory operations. It was hypothesized that adding illustrations to instructional text may lessen age-related performance differences by minimizing processing demands on working memory in the elderly. In the present study, younger and older adults constructed a series of 3-dimensional objects from 3 types of instructions (text only, illustration only, or text and illustrations). Results indicated that instructions consisting of text and illustrations reduced errors in construction for both age groups compared with the other formats. Younger adults, however, outperformed older adults under all instructional format conditions. Measures of spatial and verbal working memory and text comprehension ability accounted for substantial age-related variance across the different format conditions but did not fully account for the age differences observed.
NASA Technical Reports Server (NTRS)
Meyer, Tom; Zubrin, Robert
1997-01-01
The first phase of the research includes a comprehensive analytical study examining the potential applications for engineering subsystems and mission strategies made possible by such RWGS based subsystems, and will include an actual experimental demonstration and performance characterization of a full-scale brassboard RWGS working unit. By the time of this presentation the laboratory demonstration unit will not yet be operational but we will present the results of our analytical studies to date and plans for the ongoing work.
Traffic Flow Management and Optimization
NASA Technical Reports Server (NTRS)
Rios, Joseph Lucio
2014-01-01
This talk will present an overview of Traffic Flow Management (TFM) research at NASA Ames Research Center. Dr. Rios will focus on his work developing a large-scale, parallel approach to solving traffic flow management problems in the national airspace. In support of this talk, Dr. Rios will provide some background on operational aspects of TFM as well a discussion of some of the tools needed to perform such work including a high-fidelity airspace simulator. Current, on-going research related to TFM data services in the national airspace system and general aviation will also be presented.
Telecommuting (Work-At-Home) at NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
Srinidhi, Saragur M.
1994-01-01
This report presents a study in evaluating the viability of providing a work-at-home (telecommuting) program for Lewis Research Center's corporate employees using Integrated Services Digital Network (ISDN). Case studies have been presented for a range of applications from casual data access to interactive access. The network performance of telemedia applications were studied against future requirements for such level of remote connectivity. Many of the popular ISDN devices were characterized for network and service functionality. A set of recommendations to develop a telecommuting policy have been proposed.
Portability scenarios for intelligent robotic control agent software
NASA Astrophysics Data System (ADS)
Straub, Jeremy
2014-06-01
Portability scenarios are critical in ensuring that a piece of AI control software will run effectively across the collection of craft that it is required to control. This paper presents scenarios for control software that is designed to control multiple craft with heterogeneous movement and functional characteristics. For each prospective target-craft type, its capabilities, mission function, location, communications capabilities and power profile are presented and performance characteristics are reviewed. This work will inform future work related to decision making related to software capabilities, hardware control capabilities and processing requirements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liang, Xin; Ren, Zhibo; Zhu, Xiaolin
In the present work, cobalt nanochains have been successfully synthesized by a novel co assisted self-assembling formation strategy. A dramatic morphology transformation from cobalt nanoparticles to nanochains are observed when co molecules were introduced into the synthetic system. DFT calculations further confirm that competitive co-adsorbed co and oleylamine over the cobalt nanoparticles facilitates the formation of cobalt nanochains, which show higher co hydrogenation performance. The present work provides a new strategic and promising method for controllable synthesis of catalyst nanomaterials with the preferred surface structure and morphology.
Miranda, Ana; Colomer, Carla; Mercader, Jessica; Fernández, M Inmaculada; Presentación, M Jesús
2015-01-01
The early assessment of the executive processes using ecologically valid instruments is essential for identifying deficits and planning actions to deal with possible adverse consequences. The present study has two different objectives. The first objective is to analyze the relationship between preschoolers' performance on tests of Working Memory and Inhibition and parents' and teachers' ratings of these executive functions (EFs) using the Behavior Rating Inventory of Executive Function (BRIEF). The second objective consists of studying the predictive value of the different EF measures (performance-based test and rating scales) on Inattention and Hyperactivity/Impulsivity behaviors and on indicators of word reading performance. The participants in the study were 209 children in the last year of preschool, their teachers and their families. Performance-based tests of Working Memory and Inhibition were administered, as well as word reading measures (accuracy and speed). The parents and teachers filled out rating scales of the EF and typical behaviors of attention deficit hyperactivity disorder (ADHD) symptomatology. Moderate correlation values were found between the different EF assessments procedures, although the results varied depending on the different domains. Metacognition Index from the BRIEF presented stronger correlations with verbal working memory tests than with inhibition tests. Both the rating scales and the performance-based tests were significant predictors of Inattention and Hyperactivity/Impulsivity behaviors and the reading achievement measures. However, the BRIEF explained a greater percentage of variance in the case of the ADHD symptomatology, while the performance-based tests explained reading achievement to a greater degree. The implications of the findings for research and clinical practice are discussed.
Miranda, Ana; Colomer, Carla; Mercader, Jessica; Fernández, M. Inmaculada; Presentación, M. Jesús
2015-01-01
The early assessment of the executive processes using ecologically valid instruments is essential for identifying deficits and planning actions to deal with possible adverse consequences. The present study has two different objectives. The first objective is to analyze the relationship between preschoolers’ performance on tests of Working Memory and Inhibition and parents’ and teachers’ ratings of these executive functions (EFs) using the Behavior Rating Inventory of Executive Function (BRIEF). The second objective consists of studying the predictive value of the different EF measures (performance-based test and rating scales) on Inattention and Hyperactivity/Impulsivity behaviors and on indicators of word reading performance. The participants in the study were 209 children in the last year of preschool, their teachers and their families. Performance-based tests of Working Memory and Inhibition were administered, as well as word reading measures (accuracy and speed). The parents and teachers filled out rating scales of the EF and typical behaviors of attention deficit hyperactivity disorder (ADHD) symptomatology. Moderate correlation values were found between the different EF assessments procedures, although the results varied depending on the different domains. Metacognition Index from the BRIEF presented stronger correlations with verbal working memory tests than with inhibition tests. Both the rating scales and the performance-based tests were significant predictors of Inattention and Hyperactivity/Impulsivity behaviors and the reading achievement measures. However, the BRIEF explained a greater percentage of variance in the case of the ADHD symptomatology, while the performance-based tests explained reading achievement to a greater degree. The implications of the findings for research and clinical practice are discussed. PMID:25972833
Dipole response of 76Se above 4 MeV
NASA Astrophysics Data System (ADS)
Goddard, P. M.; Cooper, N.; Werner, V.; Rusev, G.; Stevenson, P. D.; Rios, A.; Bernards, C.; Chakraborty, A.; Crider, B. P.; Glorius, J.; Ilieva, R. S.; Kelley, J. H.; Kwan, E.; Peters, E. E.; Pietralla, N.; Raut, R.; Romig, C.; Savran, D.; Schnorrenberger, L.; Smith, M. K.; Sonnabend, K.; Tonchev, A. P.; Tornow, W.; Yates, S. W.
2013-12-01
The dipole response of 3476Se in the energy range from 4 to 9 MeV has been analyzed using a (γ⃗,γ') polarized photon scattering technique, performed at the High Intensity γ-Ray Source facility at Triangle Universities Nuclear Laboratory, to complement previous work performed using unpolarized photons. The results of this work offer both an enhanced sensitivity scan of the dipole response and an unambiguous determination of the parities of the observed J=1 states. The dipole response is found to be dominated by E1 excitations, and can reasonably be attributed to a pygmy dipole resonance. Evidence is presented to suggest that a significant amount of directly unobserved excitation strength is present in the region, due to unobserved branching transitions in the decays of resonantly excited states. The dipole response of the region is underestimated when considering only ground state decay branches. We investigate the electric dipole response theoretically, performing calculations in a three-dimensional (3D) Cartesian-basis time-dependent Skyrme-Hartree-Fock framework.
Zeintl, Melanie; Kliegel, Matthias
2010-01-01
Generally, older adults perform worse than younger adults in complex working memory span tasks. So far, it is unclear which processes mainly contribute to age-related differences in working memory span. The aim of the present study was to investigate age effects and the roles of proactive and coactive interference in a recognition-based version of the operation span task. Younger and older adults performed standard versions and distracter versions of the operation span task. At retrieval, participants had to recognize target words in word lists containing targets as well as proactive and/or coactive interference-related lures. Results show that, overall, younger adults outperformed older adults in the recognition of target words. Furthermore, analyses of error types indicate that, while younger adults were only affected by simultaneously presented distracter words, older adults had difficulties with both proactive and coactive interference. Results suggest that age effects in complex span tasks may not be mainly due to retrieval deficits in old age. Copyright 2009 S. Karger AG, Basel.
Early top-down control of visual processing predicts working memory performance
Rutman, Aaron M.; Clapp, Wesley C.; Chadick, James Z.; Gazzaley, Adam
2009-01-01
Selective attention confers a behavioral benefit for both perceptual and working memory (WM) performance, often attributed to top-down modulation of sensory neural processing. However, the direct relationship between early activity modulation in sensory cortices during selective encoding and subsequent WM performance has not been established. To explore the influence of selective attention on WM recognition, we used electroencephalography (EEG) to study the temporal dynamics of top-down modulation in a selective, delayed-recognition paradigm. Participants were presented with overlapped, “double-exposed” images of faces and natural scenes, and were instructed to either remember the face or the scene while simultaneously ignoring the other stimulus. Here, we present evidence that the degree to which participants modulate the early P100 (97–129 ms) event-related potential (ERP) during selective stimulus encoding significantly correlates with their subsequent WM recognition. These results contribute to our evolving understanding of the mechanistic overlap between attention and memory. PMID:19413473
NASA Astrophysics Data System (ADS)
Hu, Ling-Fei; Gao, Li-Dan; Li, Zhen-Jie; Wang, Shan-Feng; Sheng, Wei-Fan; Liu, Peng; Xu, Wei
2015-09-01
The high energy resolution monochromator (HRM) is widely used in inelastic scattering programs to detect phonons with energy resolution, down to the meV level. Although the large amount of heat from insertion devices can be reduced by a high heat-load monochromator, the unbalanced heat load on the inner pair of crystals in a nested HRM can affect its overall performance. Here, a theoretical analysis of the unbalanced heat load using dynamical diffraction theory and finite element analysis is presented. By utilizing the ray-tracing method, the performance of different HRM nesting configurations is simulated. It is suggested that the heat balance ratio, energy resolution, and overall spectral transmission efficiency are the figures of merit for evaluating the performance of nested HRMs. Although the present study is mainly focused on nested HRMs working at 57Fe nuclear resonant energy at 14.4 keV, it is feasible to extend this to other nested HRMs working at different energies.
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.
Miller, Matthew James; McGuire, Kerry M.; Feigh, Karen M.
2016-01-01
The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity. The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design. PMID:28491008
Miller, Matthew James; McGuire, Kerry M; Feigh, Karen M
2017-06-01
The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity . The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design.
MSFC Skylab mission report: Saturn workshop
NASA Technical Reports Server (NTRS)
1974-01-01
The Skylab's Saturn Workshop mission performance is presented. Experiments were conducted to determine man's ability to live and work in space for extended periods, to make sun and earth investigations, and to advance science and technology in several areas of space applications. Performance is compared with design parameters, and problem causes and solutions are treated. The Saturn Workshop successfully performed its role and advanced the technology of space systems design.
Working-memory training improves developmental dyslexia in Chinese children.
Luo, Yan; Wang, Jing; Wu, Hanrong; Zhu, Dongmei; Zhang, Yu
2013-02-15
Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memory training. In the present study, thirty dyslexic children aged 8-11 years were recruited from an elementary school in Wuhan, China. They received working-memory training, including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading.
ERIC Educational Resources Information Center
Morgan, Frank T.
1977-01-01
After citing reasons for the use of flextime, a case study is presented which indicates positive effects of flextime scheduling for employees--work satisfaction, better performance, and more personal life--and the company. (SH)
36 CFR 64.13 - Performance reports.
Code of Federal Regulations, 2010 CFR
2010-07-01
... AND ALLOCATIONS FOR RECREATION AND CONSERVATION USE OF ABANDONED RAILROAD RIGHTS-OF-WAY § 64.13... reports shall briefly present the following: (a) The status of the work required under the project scope...
EMC Test Report Electrodynamic Dust Shield
NASA Technical Reports Server (NTRS)
Carmody, Lynne M.; Boyette, Carl B.
2014-01-01
This report documents the Electromagnetic Interference E M I evaluation performed on the Electrodynamic Dust Shield (EDS) which is part of the MISSE-X System under the Electrostatics and Surface Physics Laboratory at Kennedy Space Center. Measurements are performed to document the emissions environment associated with the EDS units. The purpose of this report is to collect all information needed to reproduce the testing performed on the Electrodynamic Dust Shield units, document data gathered during testing, and present the results. This document presents information unique to the measurements performed on the Bioculture Express Rack payload; using test methods prepared to meet SSP 30238 requirements. It includes the information necessary to satisfy the needs of the customer per work order number 1037104. The information presented herein should only be used to meet the requirements for which it was prepared.
Nanotechnology in Aerospace Applications
2007-03-01
CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING...logic and memory chips, sensors, catalyst support, adsorption media, actuators, etc. All early works in nanoelectronics use CNTs as a conducting...inspection cost effectively , quickly, and efficiently than the present procedures, composites, wear resistant tires, improved avionics, satellite
Tiffany Diamonds and Classical Music as Influences on the Performance of "Don Juan in Hell".
ERIC Educational Resources Information Center
Johnson, Jim
This paper analyzes Paul Gregory's 1951 production of "Don Juan in Hell," now considered to be a seminal work in the development of professional and educational readers theatre. The paper contends that the production, which presented a nondramatic work without the usual emphasis on design and spectacle, forced a reexamination of the role…
ERIC Educational Resources Information Center
Pressler, Anna-Lena; Krajewski, Kristin; Hasselhorn, Marcus
2013-01-01
The aim of the present study was to investigate whether preschool children with limitations in the visual or phonological working memory are disadvantaged in the acquisition of school relevant precursor skills at school entry. A sample of 92 children was divided into three subgroups depending on their performance in visual and phonological working…
ERIC Educational Resources Information Center
Berry, Ed D. J.; Waterman, Amanda H.; Baddeley, Alan D.; Hitch, Graham J.; Allen, Richard J.
2018-01-01
Recent research has demonstrated that, when instructed to prioritize a serial position in visual working memory (WM), adults are able to boost performance for this selected item, at a cost to nonprioritized items (e.g., Hu, Hitch, Baddeley, Zhang, & Allen, 2014). While executive control appears to play an important role in this ability, the…
ERIC Educational Resources Information Center
Mehta, Kala; Gabbard, Susan M.; Barrat, Vanessa; Lewis, Melissa; Carroll, Daniel; Mines, Richard
This report presents current information on the characteristics and work patterns of hired laborers who perform crop work in the United States. Information was obtained from interviews with 4,199 workers in 85 counties between October 1, 1996 and September 30, 1998. Chapters 1-3 provide information about the farmworkers themselves, including…
ERIC Educational Resources Information Center
McMillan, Wendy
2004-01-01
This paper is conceptually informed by a reading of Peter McLaren's work (1993). Drawing on the relationship that he signals between identity, narrative, and social action, it sets out to examine the ways in which identity shapes narratives of academic performance and consequent action. Specifically, I present the narratives of academic…
ERIC Educational Resources Information Center
Arizona Board of Regents, Phoenix.
Volume Two of a report by the Arizona Board of Regents' independent citizen commission to examine the performance of the state's three public universities presents 26 working papers in four sections. Section One, Research and Graduate Education/Universities: A State Resource, offers five papers, including: "University Research and Economic…
Husemann, Britta; Von Mach, Carolin Yvonne; Borsotto, Daniel; Zepf, Kirsten Isabel; Scharnbacher, Jutta
2009-06-01
Seated working positions are often regarded as a cause for discomfort in the musculoskeletal system. Performing work in different working positions--that is, alternating between sitting and standing (sit-stand workstation paradigm)--could help reduce physical complaints. The questions were whether performing office work partly in a standing position leads to reduced complaints and whether standing would change the efficiency of data entry office work. We investigated the effect of a sit-stand workstation paradigmd during experimental data entry office work on physical and psychological complaints and data entry efficiency by conducting a randomized controlled trial with 60 male participants ages 18 to 35 years. In this experiment, musculoskeletal complaints were reduced by a sit-stand workstation paradigm. A trend could be identified indicating a small but nonsignificant loss of efficiency in data entry while standing. A sit-stand workstation paradigm reduces musculoskeletal complaints without considerably affecting data entry efficiency under the presented study conditions (young male participants, short duration, fixed and controlled sit-stand workstation paradigm, simulated experimental working condition). According to the present data, implementing a sit-stand workstation paradigm can be an effective workplace health intervention to reduce musculoskeletal complaints. This experiment encourages further studies on the effectiveness of a sit-stand workstation paradigm. Experimental research and field studies that prove the reduction of complaints when introducing a sit-stand workstation paradigm in the workplace could be the basis for evidence-based recommendations regarding such interventions.
Durso, Francis T; Ferguson, Ashley N; Kazi, Sadaf; Cunningham, Charlene; Ryan, Christina
2015-03-01
Part of the work of a critical care nurse is to manage the threats that arise that could impede efficient and effective job performance. Nurses manage threats by employing various strategies to keep performance high and workload manageable. We investigated strategic threat management by using the Threat-Strategy Interview. Threats frequently involved technology, staff, or organizational components. The threats were managed by a toolbox of multifaceted strategies, the most frequent of which involved staff-, treatment- (patient + technology), examination- (patient + clinician), and patient-oriented strategies. The profile of strategies for a particular threat often leveraged work facets similar to the work facet that characterized the threat. In such cases, the nurse's strategy was directed at eliminating the threat (not working around it). A description at both a domain invariant level - useful for understanding strategic threat management generally - and a description at an operational, specific level - useful for guiding interventions-- are presented. A structural description of the relationship among threats, strategies, and the cues that trigger them is presented in the form of an evidence accumulation framework of strategic threat management. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Attention is required for maintenance of feature binding in visual working memory
Heider, Maike; Husain, Masud
2013-01-01
Working memory and attention are intimately connected. However, understanding the relationship between the two is challenging. Currently, there is an important controversy about whether objects in working memory are maintained automatically or require resources that are also deployed for visual or auditory attention. Here we investigated the effects of loading attention resources on precision of visual working memory, specifically on correct maintenance of feature-bound objects, using a dual-task paradigm. Participants were presented with a memory array and were asked to remember either direction of motion of random dot kinematograms of different colour, or orientation of coloured bars. During the maintenance period, they performed a secondary visual or auditory task, with varying levels of load. Following a retention period, they adjusted a coloured probe to match either the motion direction or orientation of stimuli with the same colour in the memory array. This allowed us to examine the effects of an attention-demanding task performed during maintenance on precision of recall on the concurrent working memory task. Systematic increase in attention load during maintenance resulted in a significant decrease in overall working memory performance. Changes in overall performance were specifically accompanied by an increase in feature misbinding errors: erroneous reporting of nontarget motion or orientation. Thus in trials where attention resources were taxed, participants were more likely to respond with nontarget values rather than simply making random responses. Our findings suggest that resources used during attention-demanding visual or auditory tasks also contribute to maintaining feature-bound representations in visual working memory—but not necessarily other aspects of working memory. PMID:24266343
Attention is required for maintenance of feature binding in visual working memory.
Zokaei, Nahid; Heider, Maike; Husain, Masud
2014-01-01
Working memory and attention are intimately connected. However, understanding the relationship between the two is challenging. Currently, there is an important controversy about whether objects in working memory are maintained automatically or require resources that are also deployed for visual or auditory attention. Here we investigated the effects of loading attention resources on precision of visual working memory, specifically on correct maintenance of feature-bound objects, using a dual-task paradigm. Participants were presented with a memory array and were asked to remember either direction of motion of random dot kinematograms of different colour, or orientation of coloured bars. During the maintenance period, they performed a secondary visual or auditory task, with varying levels of load. Following a retention period, they adjusted a coloured probe to match either the motion direction or orientation of stimuli with the same colour in the memory array. This allowed us to examine the effects of an attention-demanding task performed during maintenance on precision of recall on the concurrent working memory task. Systematic increase in attention load during maintenance resulted in a significant decrease in overall working memory performance. Changes in overall performance were specifically accompanied by an increase in feature misbinding errors: erroneous reporting of nontarget motion or orientation. Thus in trials where attention resources were taxed, participants were more likely to respond with nontarget values rather than simply making random responses. Our findings suggest that resources used during attention-demanding visual or auditory tasks also contribute to maintaining feature-bound representations in visual working memory-but not necessarily other aspects of working memory.
NASA Astrophysics Data System (ADS)
Desai, A. B.; Desai, K. P.; Naik, H. B.; Atrey, M. D.
2017-02-01
Thermoacoustic engines (TAEs) are devices which convert heat energy into useful acoustic work whereas thermoacoustic refrigerators (TARs) convert acoustic work into temperature gradient. These devices work without any moving component. Study presented here comprises of a combination system i.e. thermoacoustic engine driven thermoacoustic refrigerator (TADTAR). This system has no moving component and hence it is easy to fabricate but at the same time it is very challenging to design and construct optimized system with comparable performance. The work presented here aims to apply optimization technique to TADTAR in the form of response surface methodology (RSM). Significance of stack position and stack length for engine stack, stack position and stack length for refrigerator stack are investigated in current work. Results from RSM are compared with results from simulations using Design Environment for Low-amplitude Thermoacoustic Energy conversion (DeltaEC) for compliance.
Greenwood, Pamela M; Schmidt, Kevin; Lin, Ming-Kuan; Lipsky, Robert; Parasuraman, Raja; Jankord, Ryan
2018-06-21
The central role of working memory in IQ and the high heritability of working memory performance motivated interest in identifying the specific genes underlying this heritability. The FTCD (formimidoyltransferase cyclodeaminase) gene was identified as a candidate gene for allelic association with working memory in part from genetic mapping studies of mouse Morris water maze performance. The present study tested variants of this gene for effects on a delayed match-to-sample task of a large sample of younger and older participants. The rs914246 variant, but not the rs914245 variant, of the FTCD gene modulated accuracy in the task for younger, but not older, people under high working memory load. The interaction of haplotype × distance × load had a partial eta squared effect size of 0.015. Analysis of simple main effects had partial eta squared effect sizes ranging from 0.012 to 0.040. A reporter gene assay revealed that the C allele of the rs914246 genotype is functional and a main factor regulating FTCD gene expression. This study extends previous work on the genetics of working memory by revealing that a gene in the glutamatergic pathway modulates working memory in young people but not in older people. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Barriers to performing stretching exercises among Korean-Chinese female migrant workers in Korea.
Lee, Hyeonkyeong; Wilbur, JoEllen; Chae, Duckhee; Lee, Kyongeun; Lee, Meenhye
2015-01-01
The purpose of this study was to investigate the barriers to performing stretching exercise experienced by Korean-Chinese female migrant workers during a community-based 12-week stretching exercise intervention trial. Qualitative secondary data analysis was conducted using telephone counseling interview transcripts from 27 middle-aged, Korean-Chinese migrant women workers. A semistructured interview question asking barriers to performing stretching exercise was given to women who did not adhere to recommended stretching exercise. During the 12-week home-based stretching exercise intervention trial, six telephone calls were made to participants biweekly to elicit barriers to performing stretching exercise. Directed content analysis approach was utilized using three barrier categories: intrapersonal, interpersonal, and work-related environmental factors based on the ecological model. Participants experienced an average of 2.5 barriers during the study period. Intrapersonal barriers included lack of time and lack of motivation, and interpersonal barriers included no family to provide support and also a feeling resistance from coworkers. Work-related environmental barriers included frequent job changes, long working hours, lack of rest time, and unpredictable job demands. The findings highlight that migrant workers in Korea face unique work-related difficulties which present barriers to exercise. © 2014 Wiley Periodicals, Inc.
Bibliography of Publications and Presentations During FY 1972-73.
ERIC Educational Resources Information Center
Human Resources Research Organization, Alexandria, VA.
Publications and presentations developed by the Human Resources Research Organization during 1972 and 1973 are listed. Part I of the bibliography contains reports issued during 1973; each citation gives the document title, author, and the contract under which the work was performed. Part II provides abstracts for each document included in Part I…
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.
Low cost airborne microwave landing system receiver, task 3
NASA Technical Reports Server (NTRS)
Hager, J. B.; Vancleave, J. R.
1979-01-01
Work performed on the low cost airborne Microwave Landing System (MLS) receiver is summarized. A detailed description of the prototype low cost MLS receiver is presented. This detail includes block diagrams, schematics, board assembly drawings, photographs of subassemblies, mechanical construction, parts lists, and microprocessor software. Test procedures are described and results are presented.
Interference, aging, and visuospatial working memory: the role of similarity.
Rowe, Gillian; Hasher, Lynn; Turcotte, Josée
2010-11-01
Older adults' performance on working memory (WM) span tasks is known to be negatively affected by the buildup of proactive interference (PI) across trials. PI has been reduced in verbal tasks and performance increased by presenting distinctive items across trials. In addition, reversing the order of trial presentation (i.e., starting with the longest sets first) has been shown to reduce PI in both verbal and visuospatial WM span tasks. We considered whether making each trial visually distinct would improve older adults' visuospatial WM performance, and whether combining the 2 PI-reducing manipulations, distinct trials and reversed order of presentation, would prove additive, thus providing even greater benefit. Forty-eight healthy older adults (age range = 60-77 years) completed 1 of 3 versions of a computerized Corsi block test. For 2 versions of the task, trials were either all visually similar or all visually distinct, and were presented in the standard ascending format (shortest set size first). In the third version, visually distinct trials were presented in a reverse order of presentation (longest set size first). Span scores were reliably higher in the ascending version for visually distinct compared with visually similar trials, F(1, 30) = 4.96, p = .03, η² = .14. However, combining distinct trials and a descending format proved no more beneficial than administering the descending format alone. Our findings suggest that a more accurate measurement of the visuospatial WM span scores of older adults (and possibly neuropsychological patients) might be obtained by reducing within-test interference.
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
NASA Astrophysics Data System (ADS)
Peláez, Víctor; González, Roberto; San Martín, Luis Ángel; Campos, Antonio; Lobato, Vanesa
Hardware device management, and context information acquisition and abstraction are key factors to develop the ambient intelligent paradigm in smart homes. This work presents an architecture that addresses these two problems and provides a usable framework to develop applications easily. In contrast to other proposals, this work addresses performance issues specifically. Results show that the execution performance of the developed prototype is suitable for deployment in a real environment. In addition, the modular design of the system allows the user to develop applications using different techniques and different levels of abstraction.
Evaluation of Aeroservoelastic Effects on Flutter
NASA Technical Reports Server (NTRS)
Nagaraja, K. S.; Felt, Larry R.; Kraft, Raymond
1998-01-01
This report presents work performed by The Boeing Company to satisfy the deliverable "Evaluation of aeroservoelastic Effects on Symmetric Flutter" for Subtask 7 of Reference 1. The objective of this report is to incorporate the improved methods for studying the effects of a closed-loop control system on the aeroservoelastic behavior of the airplane planned under NASA HSR technical Integration Task 20 work. Also, a preliminary evaluation of the existing pitch control laws on symmetric flutter of the TCA configuration was addressed."The goal is to develop an improved modeling methodology and perform design studies that account for the aero-structures-systems interaction effects.
Field Testing of Utility Robots for Lunar Surface Operations
NASA Technical Reports Server (NTRS)
Fong, Terrence; Bualat, Maria; Deans, Matt; Allan, Mark; Bouyssounouse, Xavier; Broxton, Michael; Edwards, Laurence; Lee, Pascal; Lee, Susan Y.; Lees, David;
2008-01-01
Since 2004, NASA has been working to return to the Moon. In contrast to the Apollo missions, two key objectives of the current exploration program is to establish significant infrastructure and an outpost. Achieving these objectives will enable long-duration stays and long-distance exploration of the Moon. To do this, robotic systems will be needed to perform tasks which cannot, or should not, be performed by crew alone. In this paper, we summarize our work to develop "utility robots" for lunar surface operations, present results and lessons learned from field testing, and discuss directions for future research.
Effects of thermal aging on mechanical performance of paper
B.T. Hotle; J.M. Considine; M.J. Wald; R.E. Rowlands; K.T. Turner
2008-01-01
A missing element of paper aging research is a description of mechanical performance with aging. Tensile strength cannot be predicted directly from DP measurements, and existing models do not represent the effects of aging on strength and stiffness. The primary aim of the present work is to characterize changes of mechanical properties, such as tensile response and...
ERIC Educational Resources Information Center
Kartasidou, Lefkothea; Varsamis, Panagiotis; Sampsonidou, Anna
2012-01-01
Professionals who work with children presenting intellectual and developmental disability (IDD) and developmental coordination disorder (DCD) are concerned with their motor development and their rhythmic perception. The aim of this study is to investigate the correlation between a motor performance test and a music rhythmic test that measures…
Re-Imagining Possibilities: Honoring the Work of Carolyn Ellis and Art Bochner
ERIC Educational Resources Information Center
Santoro, Patrick; Boylorn, Robin M.
2008-01-01
As co-chairs of a tribute panel for their academic mentors, Carolyn Ellis and Art Bochner, the authors knew what the traditional responsibilities would require, but as a performer and a poet, they were inspired to do something more creative. Something poetic. Something performative. Something different. In this article, the authors present a…
ERIC Educational Resources Information Center
Henderson, Wm. Edward, Jr., Ed.
This curriculum guide is designed to assist vocational educators in presenting an articulated, performance-based course in masonry and bricklaying. Addressed in the individual units of the course are the following topics: safety, leadership, job communications, career preparation, desirable learning and work habits and attitudes, basic math…
Laboratory plasma probe studies
NASA Technical Reports Server (NTRS)
Heikkila, W. J.
1975-01-01
Diagnostic experiments performed in a collisionless plasma using CO2 as the working gas are described. In particular, simultaneous measurements that have been performed by means of Langmuir- and RF-probes are presented. A resonance occurring above the parallel resonance in the frequency characteristic of a two electrode system is interpreted as being due to the resonant excitation of electroacoustic waves.
This presentation addresses recent work performed at EPA to evaluate the potential for the photooxidation of isoprene to produce secondary organic aerosol. Analysis of the samples for methyl tetrols and 2-methylglyceric acid were performed at EPA and the University of Antwerp. T...
ERIC Educational Resources Information Center
Henderson, Wm. Edward, Jr., Ed.
This curriculum guide is designed to assist vocational educators in presenting an articulated, performance-based course in electricity and industrial electricity. Addressed in the individual units of the course (included in 11 modules) are the following topics: safety, leadership, communication skills, career preparation, good work habits and…
Ethnographic Performance: A Change Agent for Drama Teaching and Learning
ERIC Educational Resources Information Center
Sallis, R.
2014-01-01
This article considers the ways in which an ethnographic performance can be an effective means of data generation, analysis and presentation for a researcher working in collaboration with drama teachers and students in an educational setting. The creation of the ethnodramatic play was part of a three-year Ph.D. educational ethnography conducted by…
Previous work showed that trichloroethylene (TCE) impairs accuracy and latency in a signal detection task (SDT) in rats, and that these effects abate during repeated exposures if rats inhale TCE during SDT testing. The present experiment compared the effects of acute and repeated...
Creative Turbulence: Experiments in Art and Physics
NASA Astrophysics Data System (ADS)
Fonda, Enrico; Dubois, R. Luke; Camnasio, Sara; Porfiri, Maurizio; Sreenivasan, Katepalli R.; Lathrop, Daniel P.; Serrano, Daniel; Ranjan, Devesh
2016-11-01
Effective communication of basic research to non-experts is necessary to inspire the public and to justify support for science by the taxpayers. The creative power of art is particularly important to engage an adult audience, who otherwise might not be receptive to standard didactic material. Interdisciplinarity defines new trends in research, and works at the intersection of art and science are growing in popularity, even though they are often isolated experiments. We present a public-facing collaboration between physicists/engineers performing research in fluid dynamics, and audiovisual artists working in cutting-edge media installation and performance. The result of this collaboration is a curated exhibition, with supporting public programming. We present the artworks, the lesson learned from the interactions between artists and scientists, the potential outreach impact and future developments. This project is supported by the APS Public Outreach Mini Grant.
Vapor-fed microfluidic hydrogen generator.
Modestino, M A; Dumortier, M; Hosseini Hashemi, S M; Haussener, S; Moser, C; Psaltis, D
2015-05-21
Water-splitting devices that operate with humid air feeds are an attractive alternative for hydrogen production as the required water input can be obtained directly from ambient air. This article presents a novel proof-of-concept microfluidic platform that makes use of polymeric ion conductor (Nafion®) thin films to absorb water from air and performs the electrochemical water-splitting process. Modelling and experimental tools are used to demonstrate that these microstructured devices can achieve the delicate balance between water, gas, and ionic transport processes required for vapor-fed devices to operate continuously and at steady state, at current densities above 3 mA cm(-2). The results presented here show that factors such as the thickness of the Nafion films covering the electrodes, convection of air streams, and water content of the ionomer can significantly affect the device performance. The insights presented in this work provide important guidelines for the material requirements and device designs that can be used to create practical electrochemical hydrogen generators that work directly under ambient air.
Spatial serial order processing in schizophrenia.
Fraser, David; Park, Sohee; Clark, Gina; Yohanna, Daniel; Houk, James C
2004-10-01
The aim of this study was to examine serial order processing deficits in 21 schizophrenia patients and 16 age- and education-matched healthy controls. In a spatial serial order working memory task, one to four spatial targets were presented in a randomized sequence. Subjects were required to remember the locations and the order in which the targets were presented. Patients showed a marked deficit in ability to remember the sequences compared with controls. Increasing the number of targets within a sequence resulted in poorer memory performance for both control and schizophrenia subjects, but the effect was much more pronounced in the patients. Targets presented at the end of a long sequence were more vulnerable to memory error in schizophrenia patients. Performance deficits were not attributable to motor errors, but to errors in target choice. The results support the idea that the memory errors seen in schizophrenia patients may be due to saturating the working memory network at relatively low levels of memory load.
Thrailkill, Eric A; Kacelnik, Alex; Porritt, Fay; Bouton, Mark E
2016-08-01
Dogs trained to search for contraband perform a chain of behavior in which they first search for a target and then make a separate response that indicates to the trainer that they have found one. The dogs often conduct multiple searches without encountering a target and receiving the reinforcer (i.e., no contraband is present). Understanding extinction (i.e., the decline in work rate when reinforcers are no longer encountered) may assist in training dogs to work in conditions where targets are rare. We therefore trained rats on a search-target behavior chain modeled on the search behavior of working dogs. A discriminative stimulus signaled that a search response (e.g., chain pull) led to a second stimulus that set the occasion for a target response (e.g., lever press) that was reinforced by a food pellet. In Experiment 1 training with longer search durations and intermittent (partial) reinforcement of searching (i.e. some trials had no target present) both led to more persistent search responding in extinction. The loss of search behavior in extinction was primarily dependent on the number of non-reinforced searches rather than time searching without reinforcement. In Experiments 2 and 3, delivery of non-contingent reinforcers during extinction increased search persistence provided they had also been presented during training. Thus, results with rats suggest that the persistence of working dog performance (or chained behavior generally) may be improved by training with partial reinforcement of searching and non-contingent reinforcement during both training and work (extinction). Copyright © 2016 Elsevier B.V. All rights reserved.
Klein, Carina; Diaz Hernandez, Laura; Koenig, Thomas; Kottlow, Mara; Elmer, Stefan; Jäncke, Lutz
2016-01-01
Previous work highlighted the possibility that musical training has an influence on cognitive functioning. The suggested reason for this influence is the strong recruitment of attention, planning, and working memory functions during playing a musical instrument. The purpose of the present work was twofold, namely to evaluate the general relationship between pre-stimulus electrophysiological activity and cognition, and more specifically the influence of musical expertise on working memory functions. With this purpose in mind, we used covariance mapping analyses to evaluate whether pre-stimulus electroencephalographic activity is predictive for reaction time during a visual working memory task (Sternberg paradigm) in musicians and non-musicians. In line with our hypothesis, we replicated previous findings pointing to a general predictive value of pre-stimulus activity for working memory performance. Most importantly, we also provide first evidence for an influence of musical expertise on working memory performance that could distinctively be predicted by pre-stimulus spectral power. Our results open novel perspectives for better comprehending the vast influences of musical expertise on cognition.
Shift work and cognitive aging: a longitudinal study.
Bokenberger, Kathleen; Ström, Peter; Dahl Aslan, Anna K; Åkerstedt, Torbjörn; Pedersen, Nancy L
2017-09-01
Objectives The few studies of shift work and late life cognitive functioning have yielded mixed findings. The aim of the present study is to estimate the association between shift-work experience and change in cognitive performance before and after retirement age among older adults who were gainfully employed. Methods Five hundred and ninety five participants with no dementia were followed up for a mean of 17.6 standard deviation (SD) 8.8 years from a Swedish population-based sample. Participants had self-reported information on any type of shift-work experience (ever/never) in 1984 and measures of cognitive performance (verbal, spatial, memory, processing speed, and general cognitive ability) from up to 9 waves of cognitive assessments during 1986-2012. Night work history (ever/never) from 1998-2002 was available from a subsample (N=320). Early adult cognitive test scores were available for 77 men. Results In latent growth curve modeling, there were no main effects of "any-type" or night shift work on the mean scores or rate of change in any of the cognitive domains. An interaction effect between any-type shift work and education on cognitive performance at retirement was noted. Lower-educated shift workers performed better on cognitive tests than lower-educated day workers at retirement. Sensitivity analyses, however, indicated that the interactions appeared to be driven by selection effects. Lower-educated day workers demonstrated poorer cognitive ability in early adulthood than lower-educated shift workers, who may have selected jobs entailing higher cognitive demand. Conclusion There was no difference in late-life cognitive aging between individuals with a history of working shifts compared to those who had typical day work schedules during midlife.
DECIDE: a software for computer-assisted evaluation of diagnostic test performance.
Chiecchio, A; Bo, A; Manzone, P; Giglioli, F
1993-05-01
The evaluation of the performance of clinical tests is a complex problem involving different steps and many statistical tools, not always structured in an organic and rational system. This paper presents a software which provides an organic system of statistical tools helping evaluation of clinical test performance. The program allows (a) the building and the organization of a working database, (b) the selection of the minimal set of tests with the maximum information content, (c) the search of the model best fitting the distribution of the test values, (d) the selection of optimal diagnostic cut-off value of the test for every positive/negative situation, (e) the evaluation of performance of the combinations of correlated and uncorrelated tests. The uncertainty associated with all the variables involved is evaluated. The program works in a MS-DOS environment with EGA or higher performing graphic card.
Wiklund-Hörnqvist, Carola; Jonsson, Bert; Korhonen, Johan; Eklöf, Hanna; Nyroos, Mikaela
2016-01-01
The aim with the present study was to examine the relationship between the subcomponents in working memory (WM) and mathematical performance, as measured by the National tests in a sample of 597 Swedish third-grade pupils. In line with compelling evidence of other studies, individual differences in WM capacity significantly predicted mathematical performance. Dividing the sample into four groups, based on their mathematical performance, revealed that mathematical ability can be conceptualized in terms of different WM profiles. Pupils categorized as High-math performers particularly differed from the other three groups in having a significant higher phonological ability. In contrast, pupils categorized as Low-math performers were particularly characterized by having a significant lower visuo-spatial ability. Findings suggest that it is important for educators to recognize and acknowledge individual differences in WM to support mathematical achievement at an individual level. PMID:27486413
1994-07-01
In this photograph, astronaut Carl Walz performs the Performance Assessment Workstation (PAWS) experiment at the flight deck of the Space Shuttle Orbiter Columbia during the STS-65 mission. Present day astronauts are subject to a variety of stresses during spaceflight. These include microgravity, physical isolation, confinement, lack of privacy, fatigue, and changing work/rest cycles. The purpose of this experiment is to determine the effects of microgravity upon thinking skills critical to the success of operational tasks in space. The principle objective is to distinguish between the effects of microgravity on specific information-processing skills affecting performance and those of fatigue caused by long work periods. To measure these skills, the investigators use a set of computerized performance tests called the Performance Assessment Workstation, which is based on current theoretical models of human performance. The tests were selected by analyzing tasks related to space missions and their hypothesized sensitivity to microgravity. Multiple subjective measures of cumulative fatigue and changing mood states are also included for interpreting performance data.
STS-65 Mission Onboard Photograph
NASA Technical Reports Server (NTRS)
1994-01-01
In this photograph, astronaut Carl Walz performs the Performance Assessment Workstation (PAWS) experiment at the flight deck of the Space Shuttle Orbiter Columbia during the STS-65 mission. Present day astronauts are subject to a variety of stresses during spaceflight. These include microgravity, physical isolation, confinement, lack of privacy, fatigue, and changing work/rest cycles. The purpose of this experiment is to determine the effects of microgravity upon thinking skills critical to the success of operational tasks in space. The principle objective is to distinguish between the effects of microgravity on specific information-processing skills affecting performance and those of fatigue caused by long work periods. To measure these skills, the investigators use a set of computerized performance tests called the Performance Assessment Workstation, which is based on current theoretical models of human performance. The tests were selected by analyzing tasks related to space missions and their hypothesized sensitivity to microgravity. Multiple subjective measures of cumulative fatigue and changing mood states are also included for interpreting performance data.
Extravehicular activities guidelines and design criteria
NASA Technical Reports Server (NTRS)
Brown, N. E.; Dashner, T. R.; Hayes, B. C.
1973-01-01
A listing of astronaut EVA support systems and equipment, and the physical, operational, and performance characteristics of each major system are presented. An overview of the major ground based support operations necessary in the development and verification of orbital EVA systems is included. The performance and biomedical characteristics of man in the orbital EV environment are discussed. Major factors affecting astronaut EV work performance are identified and delineated as they relate to EV support systems design. Data concerning the medical and physiological aspects of spaceflight on man are included. The document concludes with an extensive bibliography, and a series of appendices which expand on some of the information presented in the main body.
Performance optimization of detector electronics for millimeter laser ranging
NASA Technical Reports Server (NTRS)
Cova, Sergio; Lacaita, A.; Ripamonti, Giancarlo
1993-01-01
The front-end electronic circuitry plays a fundamental role in determining the performance actually obtained from ultrafast and highly sensitive photodetectors. We deal here with electronic problems met working with microchannel plate photomultipliers (MCP-PMTs) and single photon avalanche diodes (SPADs) for detecting single optical photons and measuring their arrival time with picosecond resolution. The performance of available fast circuits is critically analyzed. Criteria for selecting the most suitable electronics are derived and solutions for exploiting the detector performance are presented and discussed.
Advanced Aeroelastic Technologies for Turbomachinery Application
NASA Technical Reports Server (NTRS)
DeWitt, Kenneth; Srivastava, Rakesh; Reddy, T. S. R.
2004-01-01
A summary of the work performed under the grant NCC-1068 is presented. More details can be found in the cited references. The summary is presented in two parts to represent two areas of research. In the first part, methods to analyze a high temperature ceramic guide vane subjected to cooling jets are presented, and in the second part, the effect of unsteady aerodynamic forces on aeroelastic stability as implemented into the turbo-REDUCE code are presented
Loomis, Jack M; Klatzky, Roberta L; McHugh, Brendan; Giudice, Nicholas A
2012-08-01
Spatial working memory can maintain representations from vision, hearing, and touch, representations referred to here as spatial images. The present experiment addressed whether spatial images from vision and hearing that are simultaneously present within working memory retain modality-specific tags or are amodal. Observers were presented with short sequences of targets varying in angular direction, with the targets in a given sequence being all auditory, all visual, or a sequential mixture of the two. On two thirds of the trials, one of the locations was repeated, and observers had to respond as quickly as possible when detecting this repetition. Ancillary detection and localization tasks confirmed that the visual and auditory targets were perceptually comparable. Response latencies in the working memory task showed small but reliable costs in performance on trials involving a sequential mixture of auditory and visual targets, as compared with trials of pure vision or pure audition. These deficits were statistically reliable only for trials on which the modalities of the matching location switched from the penultimate to the final target in the sequence, indicating a switching cost. The switching cost for the pair in immediate succession means that the spatial images representing the target locations retain features of the visual or auditory representations from which they were derived. However, there was no reliable evidence of a performance cost for mixed modalities in the matching pair when the second of the two did not immediately follow the first, suggesting that more enduring spatial images in working memory may be amodal.
Piccardi, Laura; Matano, Alessandro; D'Antuono, Giovanni; Marin, Dario; Ciurli, Paola; Incoccia, Chiara; Verde, Paola; Guariglia, Paola
2016-01-01
The aim of the present study was to verify if gender differences in verbal and visuo-spatial working memory would persist following right cerebral lesions. To pursue our aim we investigated a large sample (n. 346) of right brain-damaged patients and healthy participants (n. 272) for the presence of gender effects in performing Corsi and Digit Test. We also assessed a subgroup of patients (n. 109) for the nature (active vs. passive) of working memory tasks. We tested working memory (WM) administering the Corsi Test (CBT) and the Digit Span (DS) using two different versions: forward (fCBT and fDS), subjects were required to repeat stimuli in the same order that they were presented; and backward (bCBT and bDS), subjects were required to repeat stimuli in the opposite order of presentation. In this way, passive storage and active processing of working memory were assessed. Our results showed the persistence of gender-related effects in spite of the presence of right brain lesions. We found that men outperformed women both in CBT and DS, regardless of active and passive processing of verbal and visuo-spatial stimuli. The presence of visuo-spatial disorders (i.e., hemineglect) can affect the performance on Corsi Test. In our sample, men and women were equally affected by hemineglect, therefore it did not mask the gender effect. Generally speaking, the persistence of the men's superiority in visuo-spatial tasks may be interpreted as a protective factor, at least for men, within other life factors such as level of education or kind of profession before retirement.
A ROSE-based OpenMP 3.0 Research Compiler Supporting Multiple Runtime Libraries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liao, C; Quinlan, D; Panas, T
2010-01-25
OpenMP is a popular and evolving programming model for shared-memory platforms. It relies on compilers for optimal performance and to target modern hardware architectures. A variety of extensible and robust research compilers are key to OpenMP's sustainable success in the future. In this paper, we present our efforts to build an OpenMP 3.0 research compiler for C, C++, and Fortran; using the ROSE source-to-source compiler framework. Our goal is to support OpenMP research for ourselves and others. We have extended ROSE's internal representation to handle all of the OpenMP 3.0 constructs and facilitate their manipulation. Since OpenMP research is oftenmore » complicated by the tight coupling of the compiler translations and the runtime system, we present a set of rules to define a common OpenMP runtime library (XOMP) on top of multiple runtime libraries. These rules additionally define how to build a set of translations targeting XOMP. Our work demonstrates how to reuse OpenMP translations across different runtime libraries. This work simplifies OpenMP research by decoupling the problematic dependence between the compiler translations and the runtime libraries. We present an evaluation of our work by demonstrating an analysis tool for OpenMP correctness. We also show how XOMP can be defined using both GOMP and Omni and present comparative performance results against other OpenMP compilers.« less
An Effective Cache Algorithm for Heterogeneous Storage Systems
Li, Yong; Feng, Dan
2013-01-01
Modern storage environment is commonly composed of heterogeneous storage devices. However, traditional cache algorithms exhibit performance degradation in heterogeneous storage systems because they were not designed to work with the diverse performance characteristics. In this paper, we present a new cache algorithm called HCM for heterogeneous storage systems. The HCM algorithm partitions the cache among the disks and adopts an effective scheme to balance the work across the disks. Furthermore, it applies benefit-cost analysis to choose the best allocation of cache block to improve the performance. Conducting simulations with a variety of traces and a wide range of cache size, our experiments show that HCM significantly outperforms the existing state-of-the-art storage-aware cache algorithms. PMID:24453890
Okahara, Satoshi; Kataoka, Masataka; Okuda, Kuniharu; Shima, Masato; Miyagaki, Keiko; Ohara, Hitoshi
2016-01-01
[Purpose] The present study investigated the physical and mental effects of plant factory work in individuals with cervical spinal cord injury and the use of a newly developed agricultural working environment. [Subjects] Six males with C5–C8 spinal cord injuries and 10 healthy volunteers participated. [Methods] Plant factory work involved three simulated repetitive tasks: sowing, transplantation, and harvesting. Surface electromyography was performed in the dominant upper arm, upper trapezius, anterior deltoid, and biceps brachii muscles. Subjects’ moods were monitored using the Profile of Mood States. [Results] Five males with C6–C8 injuries performed the same tasks as healthy persons; a male with a C5 injury performed fewer repetitions of tasks because it took longer. Regarding muscle activity during transplantation and harvesting, subjects with spinal cord injury had higher values for the upper trapezius and anterior deltoid muscles compared with healthy persons. The Profile of Mood States vigor scores were significantly higher after tasks in subjects with spinal cord injury. [Conclusion] Individuals with cervical spinal cord injury completed the plant factory work, though it required increased time and muscle activity. For individuals with C5–C8 injuries, it is necessary to develop an appropriate environment and assistive devices to facilitate their work. PMID:27134377
Ng, Jacky Y K; Chan, Alan H S
2018-05-14
The shortage in Hong Kong of construction workers is expected to worsen in future due to the aging population and increasing construction activity. Construction work is dangerous and to help reduce the premature loss of construction workers due to work-related disabilities, this study measured the work ability of 420 Hong Kong construction workers with a Work Ability Index (WAI) which can be used to predict present and future work performance. Given the importance of WAI, in this study the effects of individual and work-related factors on WAI were examined to develop and validate a WAI model to predict how individual and work-related factors affect work ability. The findings will be useful for formulating a pragmatic intervention program to improve the work ability of construction workers and keep them in the work force.
Smith, Andrew P
2005-08-01
There is a large literature on the effects of caffeine on performance. Most of the studies have been conducted in the laboratory and further information is required on the effects of caffeine consumption on performance and safety at work. The present studies aimed to determine whether the level of caffeine consumption influenced changes in alertness and performance over the working day. Secondary analyses of a large epidemiological database were also conducted to examine associations between caffeine consumption and cognitive failures and accidents at work. In the first study 110 volunteers, all of whom were regular caffeine consumers, rated their alertness and carried out a simple reaction time task before and after work on a Monday and Friday. Caffeine consumption during the day was recorded and volunteers were sub-divided into low and high consumers on the basis of a median split (220 mg/day). The second study involved secondary analyses of a database formed by combining the Bristol Stress and Health at Work and Cardiff Health and Safety at Work studies. In the first analyses associations between caffeine consumption and frequency of cognitive failures were examined in a sample of 1253 white-collar workers. The second set of analyses examined associations between caffeine consumption and accidents at work in a sample of 1555 workers who were especially at risk of having an accident. The results from the first study showed that those who consumed higher levels of caffeine reported significantly greater increases in alertness over the working day and a significantly smaller slowing of reaction time. The results from the second study demonstrated significant associations between caffeine consumption and fewer cognitive failures and accidents at work. After controlling for possible confounding factors it was found that higher caffeine consumption was associated with about half the risk of frequent/very frequent cognitive failures and a similar reduction in risk for accidents at work. Overall, the results from the three analyses show that caffeine consumption may have benefits for performance and safety at work. Copyright (c) 2005 John Wiley & Sons, Ltd.
Separation control with fluidic oscillators in water
NASA Astrophysics Data System (ADS)
Schmidt, H.-J.; Woszidlo, R.; Nayeri, C. N.; Paschereit, C. O.
2017-08-01
The present study assesses the applicability of fluidic oscillators for separation control in water. The first part of this work evaluates the properties of the fluidic oscillators including frequency, cavitation effects, and exerted thrust. Derived from the governing internal dynamics, the oscillation frequency is found to scale directly with the jet's exit velocity and the size of the fluidic oscillator independent of the working fluid. Frequency data from various experiments collapse onto a single curve. The occurrence of cavitation is examined by visual inspection and hydrophone measurements. The oscillation frequency is not affected by cavitation because it does not occur inside the oscillators. The spectral information obtained with the hydrophone provide a reliable indicator for the onset of cavitation at the exit. The performance of the fluidic oscillators for separation control on a bluff body does not seem to be affected by the presence of cavitation. The thrust exerted by an array of fluidic oscillators with water as the working fluid is measured to be even larger than theoretically estimated values. The second part of the presented work compares the performance of fluidic oscillators for separation control in water with previous results in air. The array of fluidic oscillators is installed into the rear end of a bluff body model. The drag improvements based on force balance measurements agree well with previous wind tunnel experiments on the same model. The flow field is examined by pressure measurements and with particle image velocimetry. Similar performance and flow field characteristics are observed in both water and air.
Apples vs. Oranges: Comparison of Student Performance in a MOOC vs. a Brick-and-Mortar Class
NASA Astrophysics Data System (ADS)
Dubson, Michael
In the fall of 2013, my colleagues and I taught the calculus-based introductory physics course to 800 tuition-paying students at the University of Colorado at Boulder. At the same time we taught a free massive open online version of the same course (MOOC), through Coursera.com. The initial enrollment in the MOOC was 10,000 students, of whom 255 completed the course. Students in both courses received identical lectures with identical embedded clicker questions, identical homework assignments, and identical timed exams. We present data on participation rates and exam performance for the two groups. We find that the MOOC is like a drug targeted at a very specific population. When it works, it works well, but it works for very few students. This MOOC worked well for older, well-educated students, who already had a good understanding of Newtonian mechanics.
Executive Function, Visual Attention and the Cocktail Party Problem in Musicians and Non-Musicians.
Clayton, Kameron K; Swaminathan, Jayaganesh; Yazdanbakhsh, Arash; Zuk, Jennifer; Patel, Aniruddh D; Kidd, Gerald
2016-01-01
The goal of this study was to investigate how cognitive factors influence performance in a multi-talker, "cocktail-party" like environment in musicians and non-musicians. This was achieved by relating performance in a spatial hearing task to cognitive processing abilities assessed using measures of executive function (EF) and visual attention in musicians and non-musicians. For the spatial hearing task, a speech target was presented simultaneously with two intelligible speech maskers that were either colocated with the target (0° azimuth) or were symmetrically separated from the target in azimuth (at ±15°). EF assessment included measures of cognitive flexibility, inhibition control and auditory working memory. Selective attention was assessed in the visual domain using a multiple object tracking task (MOT). For the MOT task, the observers were required to track target dots (n = 1,2,3,4,5) in the presence of interfering distractor dots. Musicians performed significantly better than non-musicians in the spatial hearing task. For the EF measures, musicians showed better performance on measures of auditory working memory compared to non-musicians. Furthermore, across all individuals, a significant correlation was observed between performance on the spatial hearing task and measures of auditory working memory. This result suggests that individual differences in performance in a cocktail party-like environment may depend in part on cognitive factors such as auditory working memory. Performance in the MOT task did not differ between groups. However, across all individuals, a significant correlation was found between performance in the MOT and spatial hearing tasks. A stepwise multiple regression analysis revealed that musicianship and performance on the MOT task significantly predicted performance on the spatial hearing task. Overall, these findings confirm the relationship between musicianship and cognitive factors including domain-general selective attention and working memory in solving the "cocktail party problem".
Executive Function, Visual Attention and the Cocktail Party Problem in Musicians and Non-Musicians
Clayton, Kameron K.; Swaminathan, Jayaganesh; Yazdanbakhsh, Arash; Zuk, Jennifer; Patel, Aniruddh D.; Kidd, Gerald
2016-01-01
The goal of this study was to investigate how cognitive factors influence performance in a multi-talker, “cocktail-party” like environment in musicians and non-musicians. This was achieved by relating performance in a spatial hearing task to cognitive processing abilities assessed using measures of executive function (EF) and visual attention in musicians and non-musicians. For the spatial hearing task, a speech target was presented simultaneously with two intelligible speech maskers that were either colocated with the target (0° azimuth) or were symmetrically separated from the target in azimuth (at ±15°). EF assessment included measures of cognitive flexibility, inhibition control and auditory working memory. Selective attention was assessed in the visual domain using a multiple object tracking task (MOT). For the MOT task, the observers were required to track target dots (n = 1,2,3,4,5) in the presence of interfering distractor dots. Musicians performed significantly better than non-musicians in the spatial hearing task. For the EF measures, musicians showed better performance on measures of auditory working memory compared to non-musicians. Furthermore, across all individuals, a significant correlation was observed between performance on the spatial hearing task and measures of auditory working memory. This result suggests that individual differences in performance in a cocktail party-like environment may depend in part on cognitive factors such as auditory working memory. Performance in the MOT task did not differ between groups. However, across all individuals, a significant correlation was found between performance in the MOT and spatial hearing tasks. A stepwise multiple regression analysis revealed that musicianship and performance on the MOT task significantly predicted performance on the spatial hearing task. Overall, these findings confirm the relationship between musicianship and cognitive factors including domain-general selective attention and working memory in solving the “cocktail party problem”. PMID:27384330
On self-propagating methodological flaws in performance normalization for strength and power sports.
Arandjelović, Ognjen
2013-06-01
Performance in strength and power sports is greatly affected by a variety of anthropometric factors. The goal of performance normalization is to factor out the effects of confounding factors and compute a canonical (normalized) performance measure from the observed absolute performance. Performance normalization is applied in the ranking of elite athletes, as well as in the early stages of youth talent selection. Consequently, it is crucial that the process is principled and fair. The corpus of previous work on this topic, which is significant, is uniform in the methodology adopted. Performance normalization is universally reduced to a regression task: the collected performance data are used to fit a regression function that is then used to scale future performances. The present article demonstrates that this approach is fundamentally flawed. It inherently creates a bias that unfairly penalizes athletes with certain allometric characteristics, and, by virtue of its adoption in the ranking and selection of elite athletes, propagates and strengthens this bias over time. The main flaws are shown to originate in the criteria for selecting the data used for regression, as well as in the manner in which the regression model is applied in normalization. This analysis brings into light the aforesaid methodological flaws and motivates further work on the development of principled methods, the foundations of which are also laid out in this work.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mowry, Curtis Dale; Pimentel, Adam S.; Sparks, Elizabeth Schares
We created interactive demonstration activities for Take Our Daughters&Sons to Work Day (TODSTWD) 2013 in order to promote general interest in chemistry and also generate awareness of the type of work our laboratories can perform. %E2%80%9CCurious about Mars Rover Curiosity?%E2%80%9D performed an elemental analysis on rocks brought to our lab using the same technique utilized on the planet Mars by the NASA robotic explorer Curiosity. %E2%80%9CFood is Chemistry?%E2%80%9D utilized a mass spectrometer to measure, in seconds, each participant's breath in order to identify the food item consumed for the activity. A total of over 130 children participated in these activitiesmore » over a 3 hour block, and feedback was positive. This document reports the materials (including handouts), experimental procedures, and lessons learned so that future demonstrations can benefit from the baseline work performed. We also present example results used to prepare the Food activity and example results collected during the Curiosity demo.« less
FY 1987 current fiscal year work plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
This Current Year Work Plan presents a detailed description of the activities to be performed by the Joint Integration Office during FY87. It breaks down the activities into two major work areas: Program Management and Program Analysis. Program Management is performed by the JIO by providing technical planning and guidance for the development of advanced TRU waste management capabilities. This includes equipment/facility design, engineering, construction, and operations. These functions are integrated to allow transition from interim storage to final disposition. JIO tasks include program requirements identification, long-range technical planning, budget development, program planning document preparation, task guidance, task monitoring, informationmore » gathering and task reporting to DOE, interfacing with other agencies and DOE lead programs, integrating public involvement with program efforts, and preparation of program status reports for DOE. Program Analysis is performed by the JIO to support identification and assessment of alternatives, and development of long-term TRU waste program capabilities. This work plan includes: system analyses, requirements analyses, interim and procedure development, legislative and regulatory analyses, dispatch and traffic analyses, and data bases.« less
Bullying among radiation therapists: effects on job performance and work environment.
Trad, Megan; Johnson, Jordan
2014-01-01
To identify the effects of workplace bullying in the radiation therapy department on job performance and explore the environment and morale of individuals who work with a bully. A quantitative research study was designed to assess the prevalence and effects of bullying in the radiation therapy workplace. A total of 308 radiation therapists participated in the study for a return rate of 46%. Of those, 194 indicated that workplace bullying was present either in their current workplace or in a previous radiation therapy environment and that it negatively affected job performance and satisfaction. Findings of this study indicate a need for evaluation of the radiation therapy workplace, education on how to identify and prevent bullying behavior, and better communication among members of the radiation therapy environment. Participants indicated that working in a hostile environment led to forgetfulness, ineffective communication, and perceived discrepancies in promotion and treatment by management. Any bullying behavior contributes to an overall toxic work environment, which is unhealthy and unsafe for patients and therapists. Those who manage therapists should promote a culture of safety and embrace their staff's independence.
Oscillating-flow regenerator test rig
NASA Technical Reports Server (NTRS)
Wood, J. G.; Gedeon, D. R.
1994-01-01
This report summarizes work performed in setting up and performing tests on a regenerator test rig. An earlier status report presented test results, together with heat transfer correlations, for four regenerator samples (two woven screen samples and two felt metal samples). Lessons learned from this testing led to improvements to the experimental setup, mainly instrumentation as well as to the test procedure. Given funding and time constraints for this project it was decided to complete as much testing as possible while the rig was set up and operational, and to forego final data reduction and analysis until later. Additional testing was performed on several of the previously tested samples as well an on five newly fabricated samples. The following report is a summary of the work performed at OU, with many of the final test results included in raw data form.
Plasma wave experiment for the ISEE-3 mission
NASA Technical Reports Server (NTRS)
Scarf, F. L.
1982-01-01
Analysis of data from a scientific instrument designed to study solar wind and plasma wave phenomena on the ISEE-3 mission is presented. The performance of work on the data analysis phase is summarized.
Self Insuring against Asbestos Removal Risks.
ERIC Educational Resources Information Center
Slutzky, Lorence H.
1987-01-01
Asbestos removal is costly and many contractors have difficulty in obtaining insurance coverage. Presents a case for self insuring if contractors perform the removal work in compliance with state and federal regulations. Includes a reference list. (MD)
ERIC Educational Resources Information Center
Meneghetti, Chiara; Gyselinck, Valerie; Pazzaglia, Francesca; De Beni, Rossana
2009-01-01
The present study investigates the relation between spatial ability and visuo-spatial and verbal working memory in spatial text processing. In two experiments, participants listened to a spatial text (Experiments 1 and 2) and a non-spatial text (Experiment 1), at the same time performing a spatial or a verbal concurrent task, or no secondary task.…
OMEGA FY13 HED requests - LANL
DOE Office of Scientific and Technical Information (OSTI.GOV)
Workman, Jonathan B; Loomis, Eric N
2012-06-25
This is a summary of scientific work to be performed on the OMEGA laser system located at the Laboratory for Laser Energetics in Rochester New York. The work is funded through Science and ICF Campagins and falls under the category of laser-driven High-Energy Density Physics experiments. This summary is presented to the Rochester scheduling committee on an annual basis for scheduling and planning purposes.
ERIC Educational Resources Information Center
American Chemical Society, Columbus, OH. Chemical Abstracts Service.
This Annual Report describes in detail the work performed during the first year of Task III of Contract NSF-C414 and the present status of Task III work. The programs and achievements described constitute the first significant efforts to develop a user-oriented, cooperative program between major secondary scientific and technical information…
Gordon-Salant, Sandra; Cole, Stacey Samuels
2016-01-01
This study aimed to determine if younger and older listeners with normal hearing who differ on working memory span perform differently on speech recognition tests in noise. Older adults typically exhibit poorer speech recognition scores in noise than younger adults, which is attributed primarily to poorer hearing sensitivity and more limited working memory capacity in older than younger adults. Previous studies typically tested older listeners with poorer hearing sensitivity and shorter working memory spans than younger listeners, making it difficult to discern the importance of working memory capacity on speech recognition. This investigation controlled for hearing sensitivity and compared speech recognition performance in noise by younger and older listeners who were subdivided into high and low working memory groups. Performance patterns were compared for different speech materials to assess whether or not the effect of working memory capacity varies with the demands of the specific speech test. The authors hypothesized that (1) normal-hearing listeners with low working memory span would exhibit poorer speech recognition performance in noise than those with high working memory span; (2) older listeners with normal hearing would show poorer speech recognition scores than younger listeners with normal hearing, when the two age groups were matched for working memory span; and (3) an interaction between age and working memory would be observed for speech materials that provide contextual cues. Twenty-eight older (61 to 75 years) and 25 younger (18 to 25 years) normal-hearing listeners were assigned to groups based on age and working memory status. Northwestern University Auditory Test No. 6 words and Institute of Electrical and Electronics Engineers sentences were presented in noise using an adaptive procedure to measure the signal-to-noise ratio corresponding to 50% correct performance. Cognitive ability was evaluated with two tests of working memory (Listening Span Test and Reading Span Test) and two tests of processing speed (Paced Auditory Serial Addition Test and The Letter Digit Substitution Test). Significant effects of age and working memory capacity were observed on the speech recognition measures in noise, but these effects were mediated somewhat by the speech signal. Specifically, main effects of age and working memory were revealed for both words and sentences, but the interaction between the two was significant for sentences only. For these materials, effects of age were observed for listeners in the low working memory groups only. Although all cognitive measures were significantly correlated with speech recognition in noise, working memory span was the most important variable accounting for speech recognition performance. The results indicate that older adults with high working memory capacity are able to capitalize on contextual cues and perform as well as young listeners with high working memory capacity for sentence recognition. The data also suggest that listeners with normal hearing and low working memory capacity are less able to adapt to distortion of speech signals caused by background noise, which requires the allocation of more processing resources to earlier processing stages. These results indicate that both younger and older adults with low working memory capacity and normal hearing are at a disadvantage for recognizing speech in noise.
[Occupational medicine and communication: which role for print media?].
Cecaro, M; Bernardini, M; Isolani, L; Passamonti, C
2010-01-01
The diffusion of recent regulations on work safety has captured mass-media's interest on work accidents. The present work aims to highlight the role of print media in building a social representation of work safety, by performing a qualitative analysis of articles published between 2009 and 2010 in three of the main national newspapers. Results showed that print media are accurate in reporting news, but they do not serve as source of education in work safety's issues. Information is mainly focused around catastrophic events, with headlines inducing negative emotions. Very few articles contain a critical discussion of methods and operational proposals tested around the Country. A possible transformation of media's role in promoting work safety is discussed.
[Working memory abilities and the severity of phonological disorders].
Linassi, Lisiane Zorzella; Keske-Soares, Marcia; Mota, Helena Bolli
2005-01-01
Working memory. To verify the performance of working memory abilities and their relation with the severity of phonological disorders. 45 children, with ages between 5.0 and 7.11 years, with evolutional phonological disorders (EFD), 17 female and 18 male, were evaluated. All subjects were assessed using the Child Phonological Evaluation proposed by Yavas et al. (1991). The severity of the disorder was determined by the Percentage of Correct Consonants (PCC) proposed by Shriberg and Kwiatkowski (1982), classifying the phonological disorder as severe, moderate-severe, average-moderate and average. After that, subtest 5 of the Psycholinguistic Abilities Test (ITPA--Bogossian & Santos, 1977) and the non-word repetition test (Kessler, 1997) were applied. After analyzing the data according the statistical tests of Kruskal Wallis and Duncan, it was verified that the performance of moderate-severe and severe individuals in the non-word repetition test was inferior to that of average-moderate and average individuals. However, performance results in the digit repetition test did not present a positive correlation with severity. The performance of phonological memory has a relation with the severity of phonological disorders. This allows us to accept the idea that the phonologic memory is related to speech production. Regarding the central executor, the results indicate that the performance in digit repetition, used to assess the central executor, did not present a correlation with the severity of the disorder. This can be justified by the fact that the central executor is more directly related to vocabulary acquisition and is responsible for processing and storing information.
Passive solar water heating: breadbox design for the Fred Young Farm Labor Center in Indio
DOE Office of Scientific and Technical Information (OSTI.GOV)
Melzer, B; Maeda, B
1979-10-01
An appropriate passive solar preheater for multifamily housing units in the Fred Young Farm Labor Center in Indio, California, was designed and analyzed. A brief summary of passive preheater systems and the key design features used in current designs is presented. The design features necessary for the site requirements are described. The eight preliminary preheater designs reviewed for the project are presented. The results of thermal performance simulation for the eight prototype systems are discussed. Alternative monitoring systems for the installation are described and evaluated. The consultants' recommendations, working drawings, and performance estimates of the system selected are presented. (MHR)
Mobile work: Ergonomics in a rapidly changing work environment.
Honan, Meg
2015-01-01
Places of work have been completely transformed by innovations in mobile work tools and ever-present access to internet data. This article characterizes use patterns and provides preliminary considerations for productive and comfortable use of common mobile devices. Two surveys described trends in mobile work. In the first, ergonomics professionals who oversee programs reported common mobile devices, their users and what data is accessed. The second, an end user survey, explored common activities performed on mobile devices, duration of use and locations where mobile work is common. The survey results provide a baseline data point for the status of mobile work in early 2014. Research indicates that additional risks have been introduced to the neck, thumbs and hands when using mobile devices. Possible trends regarding device use and work locations emerge. Intervention studies provide some direction for the practitioner. Practical strategies are outlined to reduce exposure intensity and duration. Contemporary mobile work presents tremendous change and opportunity for ergonomists and researchers to keep pace with fitting the changing models of work to the person. Continued research is needed on current mobile device use patterns to better understand ergonomic risk exposure in this rapidly changing realm.
Ogbonnaya, Chidiebere; Daniels, Kevin; Connolly, Sara; van Veldhoven, Marc
2017-01-01
We investigate the positive relationships between high-performance work practices (HPWP) and employee health and well-being and examine the conflicting assumption that high work intensification arising from HPWP might offset these positive relationships. We present new insights on whether the combined use (or integrated effects) of HPWP has greater explanatory power on employee health, well-being, and work intensification compared to their isolated or independent effects. We use data from the 2004 British Workplace Employment Relations Survey (22,451 employees nested within 1,733 workplaces) and the 2010 British National Health Service Staff survey (164,916 employees nested within 386 workplaces). The results show that HPWP have positive combined effects in both contexts, and work intensification has a mediating role in some of the linkages investigated. The results also indicate that the combined use of HPWP may be sensitive to particular organizational settings, and may operate in some sectors but not in others. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Experimental Forecasts of Wildfire Pollution at the Canadian Meteorological Centre
NASA Astrophysics Data System (ADS)
Pavlovic, Radenko; Beaulieu, Paul-Andre; Chen, Jack; Landry, Hugo; Cousineau, Sophie; Moran, Michael
2016-04-01
Environment and Climate Change Canada's Canadian Meteorological Centre Operations division (CMCO) has been running an experimental North American air quality forecast system with near-real-time wildfire emissions since 2014. This system, named FireWork, also takes anthropogenic and other natural emission sources into account. FireWork 48-hour forecasts are provided to CMCO forecasters and external partners in Canada and the U.S. twice daily during the wildfire season. This system has proven to be very useful in capturing short- and long-range smoke transport from wildfires over North America. Several upgrades to the FireWork system have been made since 2014 to accommodate the needs of operational AQ forecasters and to improve system performance. In this talk we will present performance statistics and some case studies for the 2014 and 2015 wildfire seasons. We will also describe current limitations of the FireWork system and ongoing and future work planned for this air quality forecast system.
Escarce, Andrezza Gonzalez; Lemos, Stela Maris Aguiar; Carvalho, Sirley Alves da Silva
2016-01-01
To analyze the correlation between the satisfaction of professionals from the Hearing Health Care network in two micro-regions of Minas Gerais state and the sociodemographic profile, work process, and work performance in the health service. This is a cross-sectional, observational, analytic study with a non-probabilistic sample including 34 professionals from the Hearing Health Care services. Data collection occurred through individual interviews in the municipality of professional practice. Associations between the Professional Satisfaction variable and the explanatory variables Sociodemographic Data, Work Routine, and Developed Actions were conducted. Professionals with graduate studies were more satisfied with the human resources policy and the activities developed, whereas health civil servants showed more satisfaction with the wage policy and the work schedule. The correlation analysis between work process and satisfaction revealed a moderate positive correlation between items such as Health Promotion Actions, Satisfaction with Diagnostic Equipment, and Satisfaction with Maintenance Equipment. The present study revealed a higher level of satisfaction among professionals with graduate studies (human resources policy and activities developed) and civil servants (wage policy and work schedule). The relevance of this study lies on the important role that health professionals play on the Health Care Network. Additionally, the study of satisfaction level can provide a search for improvements, considering that satisfied professionals not only improve service quality, but also show greater creativity, commitment, and performance.
OARE STS-78 (LMS-1) Final Report
NASA Technical Reports Server (NTRS)
Rice, James E.
1996-01-01
The report is organized into sections representing the phases of work performed in analyzing the STS-78 (LMS-1) results. Section 1 briefly outlines the Orbital Acceleration Research Experiment (OARE) system features, coordinates, and measurement parameters. Section 2 describes the results from STS-78. The mission description, data calibration, and representative data obtained on STS-78 are presented. Also, the anomalous performance of OARE on STS-78 is discussed. Finally, Section 3 presents a discussion of accuracy achieved and achievable with OARE. Appendix A discusses the data processing methodology in detail.
Distributed Control with Collective Intelligence
NASA Technical Reports Server (NTRS)
Wolpert, David H.; Wheeler, Kevin R.; Tumer, Kagan
1998-01-01
We consider systems of interacting reinforcement learning (RL) algorithms that do not work at cross purposes , in that their collective behavior maximizes a global utility function. We call such systems COllective INtelligences (COINs). We present the theory of designing COINs. Then we present experiments validating that theory in the context of two distributed control problems: We show that COINs perform near-optimally in a difficult variant of Arthur's bar problem [Arthur] (and in particular avoid the tragedy of the commons for that problem), and we also illustrate optimal performance in the master-slave problem.
Cross-modal working memory binding and word recognition skills: how specific is the link?
Wang, Shinmin; Allen, Richard J
2018-04-01
Recent research has suggested that the creation of temporary bound representations of information from different sources within working memory uniquely relates to word recognition abilities in school-age children. However, it is unclear to what extent this link is attributable specifically to the binding ability for cross-modal information. This study examined the performance of Grade 3 (8-9 years old) children on binding tasks requiring either temporary association formation of two visual items (i.e., within-modal binding) or pairs of visually presented abstract shapes and auditorily presented nonwords (i.e., cross-modal binding). Children's word recognition skills were related to performance on the cross-modal binding task but not on the within-modal binding task. Further regression models showed that cross-modal binding memory was a significant predictor of word recognition when memory for its constituent elements, general abilities, and crucially, within-modal binding memory were taken into account. These findings may suggest a specific link between the ability to bind information across modalities within working memory and word recognition skills.
Bantoft, Christina; Summers, Mathew J; Tranent, Peter J; Palmer, Matthew A; Cooley, P Dean; Pedersen, Scott J
2016-02-01
In the present study, we examined the effect of working while seated, while standing, or while walking on measures of short-term memory, working memory, selective and sustained attention, and information-processing speed. The advent of computer-based technology has revolutionized the adult workplace, such that average adult full-time employees spend the majority of their working day seated. Prolonged sitting is associated with increasing obesity and chronic health conditions in children and adults. One possible intervention to reduce the negative health impacts of the modern office environment involves modifying the workplace to increase incidental activity and exercise during the workday. Although modifications, such as sit-stand desks, have been shown to improve physiological function, there is mixed information regarding the impact of such office modification on individual cognitive performance and thereby the efficiency of the work environment. In a fully counterbalanced randomized control trial, we assessed the cognitive performance of 45 undergraduate students for up to a 1-hr period in each condition. The results indicate that there is no significant change in the measures used to assess cognitive performance associated with working while seated, while standing, or while walking at low intensity. These results indicate that cognitive performance is not degraded with short-term use of alternate workstations. © 2015, Human Factors and Ergonomics Society.
Hoffmann, H; Kupper, Z
1997-01-17
Earlier studies suggest that social competence has a higher predictive value for vocational outcome than psychopathology. These studies, however, show methodological shortcomings, including the fact that the instruments used for assessing social competence, psychopathology and work performance are strongly interrelated. The present study, involving a population of 34 chronically schizophrenic outpatients enrolled in a vocational rehabilitation program, was conducted in order to determine: (1) how closely the Role Play Test, the Positive and Negative Syndrome Scale and the Work Behavior Assessment Scale are related to each other; and (2) whether social competence is a better predictor of work performance and outcome of vocational rehabilitation than psychopathology. Factor analysis has revealed that the instruments are interrelated, mainly in the dimensions of negative symptoms, social relationships, non-verbal measures of social competence and conceptual disorganization. In backward regression analyses, psychopathological indicators proved to be the best predictors of work performance both cross-sectionally as well as in the longterm course. In the traditional two-syndrome model of schizophrenic psychopathology only negative symptoms were left in the regression model. In a four-dimension model the disorder of relating and the conceptual disorganization dimension were the best predictors. Differences between disorder of relating and social competence, assessed by the Role Play Test, are discussed here as well as the implications of this study for rehabilitation.
Word Spelling Assessment Using ICT: The Effect of Presentation Modality
ERIC Educational Resources Information Center
Sarris, Menelaos; Panagiotakopoulos, Chris
2010-01-01
Up-to-date spelling process was assessed using typical spelling-to-dictation tasks, where children's performance was evaluated mainly in terms of spelling error scores. In the present work a simple graphical computer interface is reported, aiming to investigate the effects of input modality (e.g. visual and verbal) in word spelling. The software…
ERIC Educational Resources Information Center
Hutchison, Keith A.
2011-01-01
Hypothesized top-down and bottom-up mechanisms of control within conflict-rich environments were examined by presenting participants with a Stroop task in which specific words were usually presented in either congruent or incongruent colors. Incongruent colors were either frequently (high contingency) or infrequently (low contingency) paired with…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Young Jin
The PowerPoint presentation focused on research goals, specific information about the atomic magnetometer, response and resolution factors of the SERF magnetometer, FC+AM systems, tests of field transfer and resolution on FC, gradient cancellation, testing of AM performance, ideas for a multi-channel AM, including preliminary sensitivity testing, and a description of a 6 channel DAQ system. A few ideas for future work ended the presentation.
Advanced Fiber Optic-Based Sensing Technology for Unmanned Aircraft Systems
NASA Technical Reports Server (NTRS)
Richards, Lance; Parker, Allen R.; Piazza, Anthony; Ko, William L.; Chan, Patrick; Bakalyar, John
2011-01-01
This presentation provides an overview of fiber optic sensing technology development activities performed at NASA Dryden in support of Unmanned Aircraft Systems. Examples of current and previous work are presented in the following categories: algorithm development, system development, instrumentation installation, ground R&D, and flight testing. Examples of current research and development activities are provided.