Asymptotic distribution of products of sums of independent random ...

Indian Academy of Sciences (India)

integrable random variables (r.v.) are asymptotically log-normal. This fact ... the product of the partial sums of i.i.d. positive random variables as follows. .... Now define ..... by Henan Province Foundation and Frontier Technology Research Plan.

Identification and analysis of cytochrome P450IID6 antigenic sites recognized by anti-liver-kidney microsome type-1 antibodies (LKM1).

Science.gov (United States)

Yamamoto, A M; Cresteil, D; Boniface, O; Clerc, F F; Alvarez, F

1993-05-01

Anti-liver-kidney microsome type-1 antibodies (LKM1), present in sera from a group of patients with autoimmune hepatitis, are directed against P450IID6. Previous work, using cDNA constructions spanning most of the P450IID6 protein defined the main immunogenic site between the amino acids (aa), 254-271 and predicted the presence of other putative immunogenic sites in the molecule. Fusion proteins from new cDNA constructions, spanning so-far-untested regions between aa 1-125 and 431-522, were not recognized by LKM1-positive sera. Synthetic peptides, representing sequences from putative immunogenic regions or previously untested regions, allowed a precise definition of four antigenic sites located between peptides 257-269, 321-351, 373-389 and 410-429, which were recognized, respectively, by 14, 8, 1 and 2 out of 15 LKM1-positive sera tested. The minimal sequence of the main antigenic site (peptide 257-269) recognized by the autoantibody was established to be WDPAQPPRD (peptide 262-270). In addition, deletion and replacement experiments showed that aa 263 (Asp) was essential for the binding of the autoantibody to peptide 262-270. Analysis of the second most frequently recognized peptide between aa 321-351, was performed using peptides 321-339 and 340-351 in competitive inhibition studies. Complete elimination of antibody binding to peptide 321-351 obtained by absorption of both shorter peptides indicated that peptide 321-351 is a discontinuous antigenic site. LKM1-positive sera reacting against peptide 321-351 recognized either both the shorter peptides or just one of them preferentially. Results of the present study suggest that the production of LKM1 antibodies is an antigen-driven, poly- or oligoclonal B cell response. The identification of antigenic sites will allow: (i) the development of specific diagnostic tests and (ii) further studies on the pathogenic value of LKM1 antibodies in autoimmune hepatitis.

Characterization of Cleaning and Disinfecting Tasks and Product Use Among Hospital Occupations

Science.gov (United States)

Saito, Rena; Virji, M. Abbas; Henneberger, Paul K.; Humann, Michael J.; LeBouf, Ryan F.; Stanton, Marcia L.; Liang, Xiaoming; Stefaniak, Aleksandr B.

2016-01-01

Background Healthcare workers have an elevated prevalence of asthma and related symptoms associated with the use of cleaning/disinfecting products. The objective of this study was to identify and characterize cleaning/disinfecting tasks and products used among hospital occupations. Methods Workers from 14 occupations at five hospitals were monitored for 216 shifts, and work tasks and products used were recorded at five-minute intervals. The major chemical constituents of each product were identified from safety data sheets. Results Cleaning and disinfecting tasks were performed with a high frequency at least once per shift in many occupations. Medical equipment preparers, housekeepers, floor strippers/waxers, and endoscopy technicians spent on average 108–177 min/shift performing cleaning/disinfecting tasks. Many occupations used products containing amines and quaternary ammonium compounds for > 100 min/shift. Conclusions This analysis demonstrates that many occupations besides housekeeping incur exposures to cleaning/disinfecting products, albeit for different durations and using products containing different chemicals. PMID:25351791

Precise lim sup behavior of probabilities of large deviations for sums of i.i.d. random variables

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Andrew Rosalsky

2004-12-01

Full Text Available Let {X,Xn;n≥1} be a sequence of real-valued i.i.d. random variables and let Sn=∑i=1nXi, n≥1. In this paper, we study the probabilities of large deviations of the form P(Sn>tn1/p, P(Sntn1/p, where t>0 and 0x1/p/ϕ(x=1, then for every t>0, limsupn→∞P(|Sn|>tn1/p/(nϕ(n=tpα.

Identification and Analysis of Multi-tasking Product Information Search Sessions with Query Logs

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Xiang Zhou

2016-09-01

Full Text Available Purpose: This research aims to identify product search tasks in online shopping and analyze the characteristics of consumer multi-tasking search sessions. Design/methodology/approach: The experimental dataset contains 8,949 queries of 582 users from 3,483 search sessions. A sequential comparison of the Jaccard similarity coefficient between two adjacent search queries and hierarchical clustering of queries is used to identify search tasks. Findings: (1 Users issued a similar number of queries (1.43 to 1.47 with similar lengths (7.3-7.6 characters per task in mono-tasking and multi-tasking sessions, and (2 Users spent more time on average in sessions with more tasks, but spent less time for each task when the number of tasks increased in a session. Research limitations: The task identification method that relies only on query terms does not completely reflect the complex nature of consumer shopping behavior. Practical implications: These results provide an exploratory understanding of the relationships among multiple shopping tasks, and can be useful for product recommendation and shopping task prediction. Originality/value: The originality of this research is its use of query clustering with online shopping task identification and analysis, and the analysis of product search session characteristics.

Task parameters affecting ergonomic demands and productivity of HVAC duct installation.

Science.gov (United States)

Mitropoulos, Panagiotis; Hussain, Sanaa; Guarascio-Howard, Linda; Memarian, Babak

2014-01-01

Mechanical installation workers experience work-related musculoskeletal disorders (WMSDs) at high rates. (1) Quantify the ergonomic demands during HVAC installation, (2) identify the tasks and task parameters that generated extreme ergonomic demands, and (3) propose improvements to reduce the WMSDs among mechanical workers. The study focused on installation of rectangular ductwork components using ladders, and analyzed five operations by two mechanical contractors. Using continuous time observational assessment, the videotaped operations were analyzed along two dimensions: (1) the production tasks and durations, and (2) the ergonomic demands for four body regions (neck, arms/shoulders, back, and knees). The analysis identified tasks with low portion of productive time and high portion of extreme postures, and task parameters that generated extreme postures. Duct alignment was the task with the highest portion of extreme postures. The position of the ladder (angle and distance from the duct) was a task parameter that strongly influenced the extreme postures for back, neck and shoulders. Other contributing factors included the difficulty to reach the hand tools when working on the ladder, the congestion of components in the ceiling, and the space between the duct and the ceiling. The identified tasks and factors provide directions for improvement.

Production Task Queue Optimization Based on Multi-Attribute Evaluation for Complex Product Assembly Workshop.

Science.gov (United States)

Li, Lian-Hui; Mo, Rong

2015-01-01

The production task queue has a great significance for manufacturing resource allocation and scheduling decision. Man-made qualitative queue optimization method has a poor effect and makes the application difficult. A production task queue optimization method is proposed based on multi-attribute evaluation. According to the task attributes, the hierarchical multi-attribute model is established and the indicator quantization methods are given. To calculate the objective indicator weight, criteria importance through intercriteria correlation (CRITIC) is selected from three usual methods. To calculate the subjective indicator weight, BP neural network is used to determine the judge importance degree, and then the trapezoid fuzzy scale-rough AHP considering the judge importance degree is put forward. The balanced weight, which integrates the objective weight and the subjective weight, is calculated base on multi-weight contribution balance model. The technique for order preference by similarity to an ideal solution (TOPSIS) improved by replacing Euclidean distance with relative entropy distance is used to sequence the tasks and optimize the queue by the weighted indicator value. A case study is given to illustrate its correctness and feasibility.

Field studies into the dynamics of product development tasks

NARCIS (Netherlands)

Oorschot, van K.E.; Bertrand, J.W.M.; Rutte, C.G.

2005-01-01

Purpose – This paper aims to describe three exploratory field studies investigating which characteristics add to later time to market and/or low product functionality of newly developed products. The studies are conducted at the level of developments tasks, or work packages. The first and second

Production Task Queue Optimization Based on Multi-Attribute Evaluation for Complex Product Assembly Workshop.

Directory of Open Access Journals (Sweden)

Lian-Hui Li

Full Text Available The production task queue has a great significance for manufacturing resource allocation and scheduling decision. Man-made qualitative queue optimization method has a poor effect and makes the application difficult. A production task queue optimization method is proposed based on multi-attribute evaluation. According to the task attributes, the hierarchical multi-attribute model is established and the indicator quantization methods are given. To calculate the objective indicator weight, criteria importance through intercriteria correlation (CRITIC is selected from three usual methods. To calculate the subjective indicator weight, BP neural network is used to determine the judge importance degree, and then the trapezoid fuzzy scale-rough AHP considering the judge importance degree is put forward. The balanced weight, which integrates the objective weight and the subjective weight, is calculated base on multi-weight contribution balance model. The technique for order preference by similarity to an ideal solution (TOPSIS improved by replacing Euclidean distance with relative entropy distance is used to sequence the tasks and optimize the queue by the weighted indicator value. A case study is given to illustrate its correctness and feasibility.

How effective is good domestic kitchen hygiene at reducing diarrhoeal disease in developed countries? A systematic review and reanalysis of the UK IID study

Directory of Open Access Journals (Sweden)

Macdonald Clare

2008-02-01

Full Text Available Abstract Background To assess whether domestic kitchen hygiene is an important contributor to the development of diarrhoea in the developed world. Methods Electronic searches were carried out in October 2006 in EMBASE, MEDLINE, Web of Knowledge, Cochrane central register of clinical trials and CINAHL. All publications, irrespective of study design, assessing food hygiene practices with an outcome measure of diarrhoea were included in the review. All included studies underwent data extraction and the data was subsequently analysed. The analysis was conducted by qualitative synthesis of the results. Given the substantial heterogeneity in study design and outcome measures meta-analysis was not done. In addition the existing dataset of the UK IID study was reanalysed to investigate possible associations between self-reported diarrhoea and variables indicative of poor domestic kitchen hygiene Results Some 14 studies were finally included in subsequent analyses. Of the 14 studies included in this systematic review, 11 were case-control studies, 2 cross-sectional surveys, and 1 RCT. Very few studies identified any significant association with good environmental kitchen hygiene. Although some of the variables in the reanalysis of the UK IID study were statistically significant no obvious trend was seen. Conclusion The balance of the available evidence does not support the hypothesis that poor domestic kitchen hygiene practices are important risk factors for diarrhoeal disease in developed countries.

Grammatical production deficits in PPA: Relating narrative and structured task performance

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Elena Barbieri

2015-05-01

Full Text Available Introduction Grammatical production impairments in primary progressive aphasia (PPA have been investigated using structured language tasks and analysis of narrative language samples (for review see Thompson & Mack, 2014; Wilson et al., 2012. However, little research has examined the relationship between them in PPA. Whereas structured tasks often assess production accuracy at different levels of syntactic complexity (e.g., Thompson et al., 2013, narrative measures typically assess overall lexical and grammatical usage (e.g., % grammatical sentences; noun-to-verb ratio, with lesser emphasis on complexity. The present study investigated the relationship between narrative measures of grammatical production and performance on structured language tests in the domains of syntax, verb morphology, and verb-argument structure (VAS. Materials and methods Data from 101 individuals with PPA were included. Participants completed a test battery including the Northwestern Assessment of Verbs and Sentences (NAVS, Thompson, 2011, the Northwestern Assessment of Verb Inflection (NAVI, Lee & Thompson, experimental version and the Northwestern Anagram Test (NAT, Thompson, Weintraub, & Mesulam, 2012. Grammatical production deficits were quantified as follows: for syntax, accuracy of non-canonical sentence production on the NAVS Sentence Production Priming Test (SPPT and the NAT; for morphology, the accuracy on finite verbs on the NAVI; for VAS, the accuracy of sentences produced with 2- and 3-argument verbs on the NAVS Argument Structure Production Test (ASPT. Cinderella narrative samples were analyzed using the Northwestern Narrative Language Analysis system (e.g., Thompson et al., 2012. For syntax, complexity was measured by the ratio of syntactically complex to simple sentences produced, whereas accuracy was indexed by computing the proportion of words with a locally grammatical lexical category. Morphological complexity was measured by mean number of verb

Effectiveness of Focus-on-Forms Instruction: Different Outcomes on Constrained- and Free-Production Tasks?

Directory of Open Access Journals (Sweden)

Giselle Corbeil

2005-06-01

Full Text Available Abstract The purpose of this study is to investigate how focus-on-forms instruction in second language teaching affects attention to forms in two different types of task: constrained and free production. These two different types of task were administered to 87 university students enrolled in a first-year French as a second language course before and after instruction on qualifying adjective agreement. Comparisons were made between learning-gain differences from pre- to post-tests for both tasks. Significant differences between pre- and post-test scores were found for both tasks. Although the difference between the two tasks was not significant, the learning-gain difference was somewhat higher for the constrained-production task than for the free-production task. When the total number of adjectives used in the compositions was broken down into colour adjectives and non-colour adjectives, no significant learning gains were observed between the two categories, although the learning gains for the non-colour adjectives was twice as high as for the colour adjectives. Possible explanations for these results are discussed.

Task A. Study of large P/sub T/ direct photon production at the ISR. Task B. Direct photon production at the tevatron (E-706). Task C. Search for fractional charge particles in semiconductors. Progress report, June 1, 1983-May 31, 1984

International Nuclear Information System (INIS)

Cleland, W.E.; Coon, D.D.; Engels, E. Jr.; Shepard, P.F.; Thompson, J.A.

1984-01-01

Task A is the Pitt contingent of the Axial Field Spectrometer Collaboration, performing experiment R807/808 at CERN. The experiment has studied several topics related to study of high P/sub T/ phenomena such as production of jets at high E/sub T/ and a comparison of their properties with jets seen in e + e - . We are working primarily on those aspects of the experiment involving reactions with photons in the final state. We are completing an analysis of prompt photons and pions produced at 11 0 in the center of mass, from data taken in 1982. Presently, new data are being taken with two large NaI arrays in place. With these data, we are studying low P/sub T/ (20 to 200 MeV/c) photon production as well as prompt photons in the range 1.5 < P/sub T/ < 4 GeV/c. For the 1.5 - 4 GeV/c data we plan to compare single photon production in pp and anti pp collisions. Task B is the Pitt contingent of the E706 collaboration, which is studying prompt photon production in πp and pp collisions at the Tevatron. The major contribution of the Pitt effort to the experiment is the provision of the array of semiconductor detectors required for the charged particle spectrometer to be used in the study of correlated hadronic jets. Task C is the search for fractional charge in semiconductors. Although the physics goals of this experiment are removed from those of the other tasks, the technical overlap with task B is extremely important. The construction and testing of semiconductor detectors requires specialized semiconductor physics knowledge and instrumentation, both of which are being developed concurrently by these two tasks. 109 references

The Effects of Multimedia Task-Based Language Teaching on EFL Learners' Oral L2 Production

Science.gov (United States)

BavaHarji, Madhubala; Gheitanchian, Mehrnaz; Letchumanan, Krishnaveni

2014-01-01

This study examined the effects of tasks, with varying levels of complexity, i.e. simple, + complex and ++ complex tasks on EFL learners' oral production in a multimedia task-based language teaching environment. 57 EFL adult learners carried out a total of 12 tasks, in sets of four tasks within three different themes and different levels of…

Task A: direct photon production (R807/808) and lepton production (NA34). Task B: direct photon production at the Tevatron (E-706). Task C: search for fractional charge particles in semiconductors. Progress report, June 1, 1984-May 31, 1985

International Nuclear Information System (INIS)

Cleland, W.E.; Coon, D.D.; Engels, E. Jr.; Shepard, P.F.; Thompson, J.A.

1984-12-01

Task A started as the support of Pitt contingent of the Axial Field Spectrometer Collaboration, performing experiment R807/808 at CERN. Last year we joined a collaboration which was formed around the same basic group to perform an experiment at the SPS, using many of the R807/808 components to set up an experiment to study lepton production (NA34). We are therefore involved both in the setting up of the new experiment, for which we have taken a major responsibility for the trigger system, and in the analysis of data from the AFS experiment. The R807/808 experiment has probed several topics related to study of high P/sub T/ phenomena such as production of jets at high E/sub T/ [1, 2, 3, 4] and a comparison of their properties with jets seen in e + e - . Task B supports the Pitt contingent of the E706 collaboration, which is studying prompt photon production in πp and pp collisions at the Tevatron. The major contribution of the Pitt effort to the experiment is the provision of the array of semiconductor detectors required for the charged particle spectrometer to be used in the study of correlated hadronic jets. Because of the physics overlap between tasks A and B, our active participation in R807/808 strengthens our contribution to E706. In particular, the πp/pp comparison in E706 complements the anti pp/pp comparison in R807/808. Task C is the search for fractional-charge in semiconductors. The major effort is the development of a new experimental technique which combines field ionization and low background infrared spectroscopy using a liquid helium cooled monochromator and a computer controlled data acquisition. 87 references

Bidirectional transfer between joint and individual actions in a task of discrete force production.

Science.gov (United States)

Masumoto, Junya; Inui, Nobuyuki

2017-07-01

The present study examined bidirectional learning transfer between joint and individual actions involving discrete isometric force production with the right index finger. To examine the effects of practice of joint action on performance of the individual action, participants performed a pre-test (individual condition), practice blocks (joint condition), and a post-test (individual condition) (IJI task). To examine the effects of practice of the individual action on performance during the joint action, the participants performed a pre-test (joint condition), practice blocks (individual condition), and a post-test (joint condition) (JIJ task). Whereas one participant made pressing movements with a target peak force of 10% maximum voluntary contraction (MVC) in the individual condition, two participants produced the target force of the sum of 10% MVC produced by each of them in the joint condition. In both the IJI and JIJ tasks, absolute errors and standard deviations of peak force were smaller post-test than pre-test, indicating bidirectional transfer between individual and joint conditions for force accuracy and variability. Although the negative correlation between forces produced by two participants (complementary force production) became stronger with practice blocks in the IJI task, there was no difference between the pre- and post-tests for the negative correlation in the JIJ task. In the JIJ task, the decrease in force accuracy and variability during the individual action did not facilitate complementary force production during the joint action. This indicates that practice performed by two people is essential for complementary force production in joint action.

Human factors interventions to reduce human errors and improve productivity in maintenance tasks

International Nuclear Information System (INIS)

Isoda, Hachiro; Yasutake, J.Y.

1992-01-01

This paper describes work in progress to develop interventions to reduce human errors and increase maintenance productivity in nuclear power plants. The effort is part of a two-phased Human Factors research program being conducted jointly by the Central Research Institute of Electric Power Industry (CRIEPI) in Japan and the Electric Power Research Institute (EPRI) in the United States. The overall objective of this joint research program is to identify critical maintenance tasks and to develop, implement and evaluate interventions which have high potential for reducing human errors or increasing maintenance productivity. As a result of the Phase 1 effort, ten critical maintenance tasks were identified. For these tasks, over 25 candidate interventions were identified for potential development. After careful analysis, seven interventions were selected for development during Phase 2. This paper describes the methodology used to analyze and identify the most critical tasks, the process of identifying and developing selected interventions and some of the initial results. (author)

Transcription factor IID in the Archaea: sequences in the Thermococcus celer genome would encode a product closely related to the TATA-binding protein of eukaryotes

Science.gov (United States)

Marsh, T. L.; Reich, C. I.; Whitelock, R. B.; Olsen, G. J.; Woese, C. R. (Principal Investigator)

1994-01-01

The first step in transcription initiation in eukaryotes is mediated by the TATA-binding protein, a subunit of the transcription factor IID complex. We have cloned and sequenced the gene for a presumptive homolog of this eukaryotic protein from Thermococcus celer, a member of the Archaea (formerly archaebacteria). The protein encoded by the archaeal gene is a tandem repeat of a conserved domain, corresponding to the repeated domain in its eukaryotic counterparts. Molecular phylogenetic analyses of the two halves of the repeat are consistent with the duplication occurring before the divergence of the archael and eukaryotic domains. In conjunction with previous observations of similarity in RNA polymerase subunit composition and sequences and the finding of a transcription factor IIB-like sequence in Pyrococcus woesei (a relative of T. celer) it appears that major features of the eukaryotic transcription apparatus were well-established before the origin of eukaryotic cellular organization. The divergence between the two halves of the archael protein is less than that between the halves of the individual eukaryotic sequences, indicating that the average rate of sequence change in the archael protein has been less than in its eukaryotic counterparts. To the extent that this lower rate applies to the genome as a whole, a clearer picture of the early genes (and gene families) that gave rise to present-day genomes is more apt to emerge from the study of sequences from the Archaea than from the corresponding sequences from eukaryotes.

Product Evaluation Task Force Phase Two report for CAGR graphite

International Nuclear Information System (INIS)

Francis, A.J.; Davies, A.

1991-01-01

It has been proposed that all Intermediate Level Wastes arising at Sellafield should be encapsulated prior to ultimate disposal. The Product Evaluation Task Force (PETF) was set up to investigate possible encapsulants and to produce an adequate data base to justify the preferred matrices. This report details the work carried out under Phase 2 of the Product Evaluation Task Force programme, on CAGR graphite. Three possible types of encapsulants for CAGR graphites:-Inorganic cements, Polymer cements and Polymers are evaluated using the Kepner Tregoe decision analysis technique. This technique provides a methodology for scoring and ranking alternative options and evaluating any risks associated with an option. The analysis shows that for all four stages of waste management operations ie Storage, Transport, handling and emplacement, Disposal and Process, cement matrices are considerably superior to other potential matrices. A matrix, consisting of three parts Blast Furnace Slag (BFS) to one part Ordinary Portland Cement (OPC) is recommended as the preferred matrix for Phase 3 studies on CAGR graphite. (author)

Physiological evidence of interpersonal dynamics in a cooperative production task

DEFF Research Database (Denmark)

Mønster, Dan; Håkonsson, Dorthe Døjbak; Eskildsen, Jacob Kjær

2016-01-01

Recent research suggests that shared behavioral dynamics during interpersonal interaction are indicative of subjective and objective outcomes of the interaction, such as feelings of rapport and success of performance. The role of shared physiological dynamics to quantify interpersonal interaction...... production task. Moreover, high team synchrony is found indicative of team cohesion, while low team synchrony is found indicative of a teams' decision to adopt a new behavior across multiple production sessions. We conclude that team-level measures of synchrony offer new and complementary information...

The Role of L2 Learner Goal Differences in Task-Generated Oral Production

Science.gov (United States)

Ben Maad, Mohamed Ridha

2016-01-01

In light of the growing interest in the cognitive approach to task in second language (L2) research, comparatively little has been done to examine such effect over time and the role of individual differences (IDs). The present study was designed to verify some longitudinal evidence for the role of tasks in L2 production and whether IDs, in the…

Hereditary sensory and autonomic neuropathy type IID caused by an SCN9A mutation.

Science.gov (United States)

Yuan, Junhui; Matsuura, Eiji; Higuchi, Yujiro; Hashiguchi, Akihiro; Nakamura, Tomonori; Nozuma, Satoshi; Sakiyama, Yusuke; Yoshimura, Akiko; Izumo, Shuji; Takashima, Hiroshi

2013-04-30

To identify the clinical features of Japanese patients with suspected hereditary sensory and autonomic neuropathy (HSAN) on the basis of genetic diagnoses. On the basis of clinical, in vivo electrophysiologic, and pathologic findings, 9 Japanese patients with sensory and autonomic nervous dysfunctions were selected. Eleven known HSAN disease-causing genes and 5 related genes were screened using a next-generation sequencer. A homozygous mutation, c.3993delGinsTT, was identified in exon 22 of SCN9A from 2 patients/families. The clinical phenotype was characterized by adolescent or congenital onset with loss of pain and temperature sensation, autonomic nervous dysfunctions, hearing loss, and hyposmia. Subsequently, this mutation was discovered in one of patient 1's sisters, who also exhibited sensory and autonomic nervous system dysfunctions, with recurrent fractures being the most predominant feature. Nerve conduction studies revealed definite asymmetric sensory nerve involvement in patient 1. In addition, sural nerve pathologic findings showed loss of large myelinated fibers in patient 1, whereas the younger patient showed normal sural nerve pathology. We identified a novel homozygous mutation in SCN9A from 2 Japanese families with autosomal recessive HSAN. This loss-of-function SCN9A mutation results in disturbances in the sensory, olfactory, and autonomic nervous systems. We propose that SCN9A mutation results in the new entity of HSAN type IID, with additional symptoms including hyposmia, hearing loss, bone dysplasia, and hypogeusia.

Information, Technology and Information Worker Productivity: Task Level Evidence

OpenAIRE

Sinan Aral; Erik Brynjolfsson; Marshall Van Alstyne

2007-01-01

In an effort to reveal the fine-grained relationships between IT use, patterns of information flows, and individual information-worker productivity, we study task level practices at a midsize executive recruiting firm. We analyze both project-level and individual-level performance using: (1) detailed accounting data on revenues, compensation, project completion rates, and team membership for over 1300 projects spanning 5 years, (2) direct observation of over 125,000 email messages over a peri...

A documentation tool for product configuration systems - improving the documentation task

DEFF Research Database (Denmark)

Hvam, Lars; Jensen, Klaes Ladeby

2005-01-01

's experience with the procedure and the hitherto empirical experience from companies having applied the procedure have revealed that there is a need for an IT-based docu-mentation tool to support the process of constructing product configuration systems. Time can be saved by letting a documentation tool handle......Configuration systems are increasingly applied to automate the configuration of complex products. A configuration system is an expert system designed to combine specified modules according to constraints. The constraints are stored as product data and rules in a product model, and one of the most...... essential tasks is thus to develop a complete and consistent product model which can reflect the actual product. A procedure for building product models has been developed at the Centre for Product Modelling (CPM), and the pro-cedure has been successfully applied in several industrial companies. CPM...

Acquisition and production of skilled behavior in dynamic decision-making tasks

Science.gov (United States)

Kirlik, Alex

1992-01-01

Detailed summaries of two NASA-funded research projects are provided. The first project was an ecological task analysis of the Star Cruiser model. Star Cruiser is a psychological model designed to test a subject's level of cognitive activity. Ecological task analysis is used as a framework to predict the types of cognitive activity required to achieve productive behavior and to suggest how interfaces can be manipulated to alleviate certain types of cognitive demands. The second project is presented in the form of a thesis for the Masters Degree. The thesis discusses the modeling of decision-making through the use of neural network and genetic-algorithm machine learning technologies.

IEA Bioenergy Task 42 - Countries report. IEA Bioenergy Task 42 on biorefineries: Co-production of fuels, chemicals, power and materials from biomass. Final report

Energy Technology Data Exchange (ETDEWEB)

Cherubini, F.; Jungmeier, G.; Mandl, M. (Joanneum Research, Graz (Austria)) (and others)

2010-07-01

This report has been developed by the members of IEA Bioenergy Task 42 on Biorefinery: Co-production of Fuels, Chemicals, Power and Materials from Biomass (www.biorefinery.nl/ieabioenergy-task42). IEA Bioenergy is a collaborative network under the auspices of the International Energy Agency (IEA) to improve international cooperation and information exchange between national bioenergy RD and D programs. IEA Bioenergy Task 42 on Biorefinery covers a new and very broad biomass-related field, with a very large application potential, and deals with a variety of market sectors with many interested stakeholders, a large number of biomass conversion technologies, and integrated concepts of both biochemical and thermochemical processes. This report contains an overview of the biomass, bioenergy and biorefinery situation, and activities, in the Task 42 member countries: Austria, Canada, Denmark, France, Germany, Ireland, and the Netherlands. The overview includes: national bioenergy production, non-energetic biomass use, bioenergy related policy goals, national oil refineries, biofuels capacity for transport purposes, existing biorefinery industries, pilot and demo plants, and other activities of research and development (such as main national projects and stakeholders). Data are provided by National Task Leaders (NTLs), whose contact details are listed at the end of the report. (author)

Quantitative Analysis of Language Production in Parkinson's Disease Using a Cued Sentence Generation Task

Science.gov (United States)

Vanhoutte, Sarah; De Letter, Miet; Corthals, Paul; Van Borsel, John; Santens, Patrick

2012-01-01

The present study examined language production skills in Parkinson's disease (PD) patients. A unique cued sentence generation task was created in order to reduce demands on memory and attention. Differences in sentence production abilities according to disease severity and cognitive impairments were assessed. Language samples were obtained from 20…

Production of False Memories in Collaborative Memory Tasks Using the DRM Paradigm

Science.gov (United States)

Saraiva, Magda; Albuquerque, Pedro B.; Arantes, Joana

2017-01-01

Studies on collaborative memory have revealed an interesting phenomenon called collaborative inhibition (CI) (i.e., nominal groups recall more information than collaborative groups). However, the results of studies on false memories in collaborative memory tasks are controversial. This study aimed to understand the production of false memories in…

Application of productive research tasks in working with gifted students in teaching Serbian language and literature

Directory of Open Access Journals (Sweden)

Stakić Mirjana M.

2015-01-01

Full Text Available In the work we examine the possibility of application of productive research tasks in working with gifted students in teaching Serbian language and literature. Using specific examples of interpretations of literary works we show that productive research assignments encourage students' creative and inventive expression, creativity, imagination and criticality and enable them to develop in accordance with their personality, individual preferences and abilities. In the examples of their use in problem solving, we determine how productive research tasks are conducive to gifted students who need to learn through problem solving and school work and to experience learning as a challenge. They present the basis for independent research, which allows gifted students to express their own creativity and the need to acquire new, challenging knowledge, and represent a powerful motivational tool that teachers can use in order to further develop their talent. Creative application of the productive research tasks in teaching Serbian language and literature is the possibility that the education of gifted students is not treated as elitist question, but to transform teaching process into development of giftedness and talent, where the role of the teacher in the teaching process rises to the role of the mentor.

Garvicin A, a Novel Class IId Bacteriocin from Lactococcus garvieae That Inhibits Septum Formation in L. garvieae Strains

Science.gov (United States)

Cárdenas, Nivia; Martínez, Beatriz; Ruiz-Barba, José Luis; Fernández-Garayzábal, José F.; Rodríguez, Juan M.; Gibello, Alicia

2013-01-01

Lactococcus garvieae 21881, isolated in a human clinical case, produces a novel class IId bacteriocin, garvicin A (GarA), which is specifically active against other L. garvieae strains, including fish- and bovine-pathogenic isolates. Purification from active supernatants, sequence analyses, and plasmid-curing experiments identified pGL5, one of the five plasmids found in L. garvieae [M. Aguado-Urda et al., PLoS One 7(6):e40119, 2012], as the coding plasmid for the structural gene of GarA (lgnA), its putative immunity protein (lgnI), and the ABC transporter and its accessory protein (lgnC and lgnD). Interestingly, pGL5-cured strains were still resistant to GarA. Other putative bacteriocins encoded by the remaining plasmids were not detected during purification, pointing to GarA as the main inhibitor secreted by L. garvieae 21881. Mode-of-action studies revealed a potent bactericidal activity of GarA. Moreover, transmission microscopy showed that GarA seems to act by inhibiting septum formation in L. garvieae cells. This potent and species-specific inhibition by GarA holds promise for applications in the prevention or treatment of infections caused by pathogenic strains of L. garvieae in both veterinary and clinical settings. PMID:23666326

Product Evaluation Task Force Phase Two report for BWR/PWR dissolver wastes

International Nuclear Information System (INIS)

Francis, A.J.

1990-01-01

It has been proposed that all Intermediate Level Wastes arising at Sellafield should be encapsulated prior to ultimate disposal. The Product Evaluation Task Force (PETF) was set up to investigate possible encapsulants and to produce an adequate data base to justify the preferred matrices. This report details the work carried out, under Phase 2 of the Product Evaluation Task Force programme, on BWR/PWR Dissolver Wastes. Three possible types of encapsulants for BWR/PWR Dissolver Wastes:- Inorganic cements, Polymer cements and Polymers are evaluated using the Kepner Tregoe decision analysis technique. This technique provides a methodology for scoring and ranking alternative options and evaluating any risks associated with an option. The analysis shows that for all four stages of waste management operations ie Storage, Transport, handling and emplacement, Disposal and Process, cement matrices are considerably superior to other potential matrices. A matrix, consisting of three parts Blast Furnace Slag (BFS) to one part Ordinary Portland Cement (OPC), is recommended for Phase 3 studies on BWR/PWR Dissolver Wastes. (author)

Product Evaluation Task Force Phase Two report for MEB crud/filter aid

International Nuclear Information System (INIS)

Francis, A.J.

1991-01-01

It has been proposed that all Intermediate Level Wastes arising at Sellafield should be encapsulated prior to ultimate disposal. The Product Evaluation Task Force (PETF) was set up to investigate possible encapsulants and to produce an adequate data base to justify the preferred matrices. This report details the work carried out, under Phase 2 of the Product Evaluation Task Force programme, on MEB Crud/Filter Aid. Three possible types of encapsulants for MEB Crud/Filter Aid:- Inorganic cements, Polymer cements, and Polymers are evaluated using the Kepner Tregoe decision and analysis technique. This technique provides a methodology for scoring and ranking alternative options and evaluating any risks associated with an option. The analysis shows that for all four stages of waste management operations, ie Storage, Transport, handling and emplacement, Disposal and, Process, cement matrices are considerably superior to other potential matrices. A matrix, consisting of nine parts Blast Furnace Slag (BFS) to one part Ordinary Portland Cement (OPC) is recommended as the preferred matrix for Phase 3 studies on MEB/Filter Aid. (author)

Introducing People – Genre Analysis and Oral Comprehension and Oral Production Tasks

Directory of Open Access Journals (Sweden)

Keila Rocha Reis de Carvalho

2012-02-01

Full Text Available This paper aims at presenting an analysis of the genre introducing people and at suggesting listening comprehension and oral production tasks. This work was developed according to the characterization of the rhetorical organization of situations taken from seventeen films that contain the genre under analysis. Although several studies in the ESP area carried out recently (Andrade, 2003; Cardoso, 2003; Shergue, 2003; Belmonte, 2003; Serafini, 2003 have identified listening comprehension and oral production as the abilities that should be prioritized in an English course, much needs to be done, especially concerning the oral genres that take into account the language the learners of English as a second language need in their target situation. This work is based on Hutchinson & Waters (1987 theoretical background on ESP, Swales’ (1990 genre analysis, Ramos’ (2004 pedagogical proposal, and also on Ellis´ (2003 tasks concept. The familiarization of learners of English as a second language with this genre will provide them with the opportunity to better understand and use the English language in their academic and professional life.

Productive international collaboration in the large coil task

International Nuclear Information System (INIS)

Haubenreich, P.N.; Komarek, P.; Shimamoto, S.; Vecsey, G.

1987-01-01

The Large Coil Task (LCT), initiated in 1977, has been very productive of useful technical information about superconducting toroidal field (TF) coil design and manufacture. Moreover, it has demonstrated close international collaboration in fusion technology development, including integration of large components built in four different countries. Each of six 40-t test coils was designed and produced by a major industrial team, with government laboratory guidance, to a common set of specifications. The six were assembled into a toroidal array for testing in the International Fusion Superconducting Magnet Test Facility (IFSMTF) at Oak Ridge. Testing was done by a team of representatives of EURATOM, Japan, Switzerland, and the United States, with each participant having full access to all data. Coils were thoroughly instrumented, enabling penetrating analysis of behavior

Authentic Tasks to Foster Oral Production among English as a Foreign Language Learners

Science.gov (United States)

Ramírez Ortiz, Sandra Milena; Artunduaga Cuéllar, Marco Tulio

2018-01-01

Attaining oral production is a challenge for most English language teachers because most of the strategies implemented in class do not engage students in speaking activities. Tasks are an optimal alternative to engage learners in communicative exchanges. This article presents the results of a qualitative action research study examining the effects…

The Effects of Pre-Task, On-Line, and Both Pre-Task and On-Line Planning on Fluency, Complexity, and Accuracy--The Case of Iranian EFL Learners' Written Production

Science.gov (United States)

Piri, Faramarz; Barati, Hossein; Ketabi, Saeed

2012-01-01

Previous studies on the effect of planning on language production have revealed that planning does have a positive effect on language performance in terms of fluency, complexity, and accuracy. The present study was an attempt to investigate the effects of pre-task, on-line, and both pre-task and on-line planning on fluency, accuracy, and…

Product behavior and appearance effects on experienced engagement during experimental and goal-directed tasks

NARCIS (Netherlands)

Rozendaal, M.C.; Keyson, D.V.; Ridder, de H.

2007-01-01

This study examines how digital products can be designed towards increased levels of experienced engagement. An experiment was conducted in which 24 participants were asked to interact with a videogame that varied in behavior and appearance aspects during experiential and goal-directed tasks.

The usability of the fashion product - analysis of user tasks in the creation and production of clothing

Directory of Open Access Journals (Sweden)

Tamissa Juliana Barreto Berton

2016-12-01

Full Text Available Clothing is an object that is in direct contact with the body, and when poorly designed can limit the individual in the daily activities, thus considering the usability of the product. This article aims to highlight the analysis of user tasks during the development of the fashion product design, showing in which steps the knowledge of movements performed by man shall be inserted. By showing stages, from research and creation until modeling, at which begins the construction of the product, it is remarkable the influence of ergonomics and anthropometry in the process, and the knowledge of the human body in its entirety is essential for the construction of clothing. For this, a literature review was performed to unite the concepts necessary to achieve the objective of the work. The subjects covered are intended to educate the fashion designer as understanding the user's activities will influence the quality of the designed product.

Is a "Complex" Task Really Complex? Validating the Assumption of Cognitive Task Complexity

Science.gov (United States)

Sasayama, Shoko

2016-01-01

In research on task-based learning and teaching, it has traditionally been assumed that differing degrees of cognitive task complexity can be inferred through task design and/or observations of differing qualities in linguistic production elicited by second language (L2) communication tasks. Without validating this assumption, however, it is…

IEA hydrogen agreement, task 15: photobiological hydrogen production - an international collaboration

International Nuclear Information System (INIS)

Lindblad, P.; Asada, Y.; Benemann, J.; Hallenbeck, P.; Melis, A.; Miyake, J.; Seibert, M.; Skulberg, O.

2000-01-01

Biological hydrogen production, the production of H 2 by microorganisms, has been an active field of basic and applied research for many years. Realization of practical processes for photobiological hydrogen production from water using solar energy would result in a major, novel source of sustainable and renewable energy, without greenhouse gas emissions or environmental pollution. However, development of such processes requires significant scientific and technological advances, and long-term basic and applied R and D. This International Energy Agency (lEA) Task covers research areas and needs at the interface of basic and applied R and D which are of mutual interest to the countries and researchers participating in the lEA Hydrogen Agreement. The overall objective is to sufficiently advance the basic and early-stage applied science in this area of research over the next five years to allow an evaluation of the potential of such a technology to be developed as a practical renewable energy source for the 21st Century. (author)

Survey of the productivity loss due to heat stress in different tasks of farmers in Darreh Shahr city

Directory of Open Access Journals (Sweden)

M. R. Monazzam Esmaielpour

2015-09-01

Full Text Available Introduction: Heat is one of the hazardous physical agents in the workplace. Exposure to heat and consequent thermal stress influence workers productivity in addition to adverse health effects. The aim of this study was to determine the heat stress induced productivity loss related to different tasks of farmers in Darreh Shahr city, during summer. . Material and Method: This cross-sectional study was conducted in summer, 2014, among farmers in Darreh Shahr city. After determining the sample size, farmers’ activities were determined using hierarchical task analysis (HTA, and WBGT measurements were done according to the ISO7243. Metabolism was estimated by the ISO8996. Following, the type of activities were identified according their required metabolism. Knowing WBGT and workload and using the work capacity model, the productivity loss in different tasks and ultimately total productivity loss were calculated. .Result: The mean WBGT activities for plowing, terracing, planting seeds, watering, fertilizing, weeding, spraying, and harvesting were 29.98 °C, 31.28 °C,30.66 °C,31.39 °C,31.99 °C,31.75 °C,31.08 °C, and 30.3 °C, respectively. WBGT values were higher than the permissible level provided by ISO7243 in all farming activities. Maximum value of WBGT was belonged to fertilizing activity (31.99 °C and the lowest value was for plowing (29.98 °C. ANOVA test results did not show a significant difference in WBGT at head, waist, and ankle height. The highest and lowest amount of productivity loss was estimated respectively for weeding and plowing activities. The total productivity loss for farming was calculated 69.3 percent in an hour which is due to high physical activity, working outdoor, with exposure to direct solar radiation, and consequent heat stress imposed to workers. .Conclusion: Productivity is a factor which is affected by the workplace heat stress. According to results of the present research, the amount of productivity is

The Effects of Pre-Task Planning and On-line Planning on Fluency, Complexity, and Accuracy in L2 Monologic Oral Production.

Science.gov (United States)

Yuan, Fangyuan; Ellis, Rod

2003-01-01

Investigated the effects of both pre-task and on-line planning on second language (L2) oral production. Results show that pre-task planning enhances grammatical complexity while on-line planning positively influences accuracy and grammatical complexity. Pre-task planners also produced more fluent and lexically varied language than the on-line…

The effects of different tasks on the comprehension and production of idioms in children.

Science.gov (United States)

Levorato, M C; Cacciari, C

1995-10-01

The present study investigated the developmental processes which lead from a literal interpretation of idiomatic expression to the ability of comprehending and producing them figuratively. A Model of the Development of Figurative Competence was presented according to which acquisition of idioms occurs as part of the general process of language and world knowledge development. Three experiments were carried out with second- and fourth-grade children, in which comprehension tasks - Recall, Multiple Choice, Paraphrase - and a production task - Completion - were employed. The results showed that younger children are more literally oriented than older children who in turn are more idiomatically oriented and that children of both age groups found it more difficult to produce idiomatic expressions than to comprehend them.

Abnormal striatal dopaminergic neurotransmission during rest and task production in spasmodic dysphonia.

Science.gov (United States)

Simonyan, Kristina; Berman, Brian D; Herscovitch, Peter; Hallett, Mark

2013-09-11

Spasmodic dysphonia is a primary focal dystonia characterized by involuntary spasms in the laryngeal muscles during speech production. The pathophysiology of spasmodic dysphonia is thought to involve structural and functional abnormalities in the basal ganglia-thalamo-cortical circuitry; however, neurochemical correlates underpinning these abnormalities as well as their relations to spasmodic dysphonia symptoms remain unknown. We used positron emission tomography with the radioligand [(11)C]raclopride (RAC) to study striatal dopaminergic neurotransmission at the resting state and during production of symptomatic sentences and asymptomatic finger tapping in spasmodic dysphonia patients. We found that patients, compared to healthy controls, had bilaterally decreased RAC binding potential (BP) to striatal dopamine D2/D3 receptors on average by 29.2%, which was associated with decreased RAC displacement (RAC ΔBP) in the left striatum during symptomatic speaking (group average difference 10.2%), but increased RAC ΔBP in the bilateral striatum during asymptomatic tapping (group average difference 10.1%). Patients with more severe voice symptoms and subclinically longer reaction time to initiate the tapping sequence had greater RAC ΔBP measures, while longer duration of spasmodic dysphonia was associated with a decrease in task-induced RAC ΔBP. Decreased dopaminergic transmission during symptomatic speech production may represent a disorder-specific pathophysiological trait involved in symptom generation, whereas increased dopaminergic function during unaffected task performance may be explained by a compensatory adaptation of the nigrostriatal dopaminergic system possibly due to decreased striatal D2/D3 receptor availability. These changes can be linked to the clinical and subclinical features of spasmodic dysphonia and may represent the neurochemical basis of basal ganglia alterations in this disorder.

Presentation-Practice-Production and Task-Based Learning in the Light of Second Language Learning Theories.

Science.gov (United States)

Ritchie, Graeme

2003-01-01

Features of presentation-practice-production (PPP) and task-based learning (TBL) models for language teaching are discussed with reference to language learning theories. Pre-selection of target structures, use of controlled repetition, and explicit grammar instruction in a PPP lesson are given. Suggests TBL approaches afford greater learning…

Effects of age and content of augmented feedback on learning an isometric force-production task

NARCIS (Netherlands)

van Dijk, Henk; Mulder, Theo; Hermens, Hermie J.

2007-01-01

This study addressed the interaction between age and the informational content of feedback on learning an isometric force-production task. Healthy men and women (30 young adults: 20 to 35 years; 30 older adults: 55 to 70 years) were randomly assigned to a certain type of feedback: knowledge of

A comparison of the responses to three comprehension and three production tasks assessing the morpho-syntactic abilities of Afrikaans-speaking preschoolers

Directory of Open Access Journals (Sweden)

Southwood, Frenette

2005-12-01

Full Text Available The lack of standardised assessment instruments for assessing the morpho-syntactic abilities of Afrikaans-speaking children often leads to the use of informal assessment tools and/or spontaneous language samples. The question that this paper addresses is how best to assess these morpho-syntactic abilities when using nonstandardised assessment instruments of this kind. The general aim of the present study was to answer this question. Eight typically developing, monolingual children (one boy and one girl of 3, 4, 5, and 6 years from monolingual Afrikaans-speaking homes participated. Tasks were administered to assess comprehension and production of grammatical features related to number, person, case, and tense, as well as questions forms, binding relations and passive constructions. The comprehension tasks entailed picture selection, judging the (incorrectness of utterances produced by the researcher, and question answering, whereas the production tasks consisted of sentence completion, question asking and a language sample. A specific aim of the study was to determine which method(s rendered the highest number of (i correct responses and (ii usable responses (i.e., responses strictly related to the aspect under assessment by these typically developing participants. The results indicate that picture selection elicited the highest number of both correct and usable responses in the comprehension tasks. The production task that provided the highest number of both correct and usable responses was language sample elicitation. This suggests that these tasks should receive precedence when assessing the morpho-syntactic abilities of Afrikaans-speaking preschool children.

Mechanical knowledge does matter to tool use even when assessed with a non-production task: Evidence from left brain-damaged patients.

Science.gov (United States)

Lesourd, Mathieu; Budriesi, Carla; Osiurak, François; Nichelli, Paolo F; Bartolo, Angela

2017-12-20

In the literature on apraxia of tool use, it is now accepted that using familiar tools requires semantic and mechanical knowledge. However, mechanical knowledge is nearly always assessed with production tasks, so one may assume that mechanical knowledge and familiar tool use are associated only because of their common motor mechanisms. This notion may be challenged by demonstrating that familiar tool use depends on an alternative tool selection task assessing mechanical knowledge, where alternative uses of tools are assumed according to their physical properties but where actual use of tools is not needed. We tested 21 left brain-damaged patients and 21 matched controls with familiar tool use tasks (pantomime and single tool use), semantic tasks and an alternative tool selection task. The alternative tool selection task accounted for a large amount of variance in the single tool use task and was the best predictor among all the semantic tasks. Concerning the pantomime of tool use task, group and individual results suggested that the integrity of the semantic system and preserved mechanical knowledge are neither necessary nor sufficient to produce pantomimes. These results corroborate the idea that mechanical knowledge is essential when we use tools, even when tasks assessing mechanical knowledge do not require the production of any motor action. Our results also confirm the value of pantomime of tool use, which can be considered as a complex activity involving several cognitive abilities (e.g., communicative skills) rather than the activation of gesture engrams. © 2017 The British Psychological Society.

XML Survey of the productivity loss due to heat stress in different tasks of farmers in Darreh Shahr city

Directory of Open Access Journals (Sweden)

M. R. Monazzam Esmaielpou

2015-09-01

Full Text Available Introduction: Heat is one of the hazardous physical agents in the workplace. Exposure to heat and consequent thermal stress influence workers productivity in addition to adverse health effects. The aim of this study was to determine the heat stress induced productivity loss related to different tasks of farmers in Darreh Shahr city, during summer. Material and Method: This cross-sectional study was conducted in summer, 2014, among farmers in Darreh Shahr city. After determining the sample size, farmers’ activities were determined using hierarchical task analysis (HTA, and WBGT measurements were done according to the ISO7243. Metabolism was estimated by the ISO8996. Following, the type of activities were identified according their required metabolism. Knowing WBGT and workload and using the work capacity model, the productivity loss in different tasks and ultimately total productivity loss were calculated. Result: The mean WBGT activities for plowing, terracing, planting seeds, watering, fertilizing, weeding, spraying, and harvesting were 29.98 °C, 31.28 °C,30.66 °C,31.39 °C,31.99 °C,31.75 °C,31.08 °C, and 30.3 °C, respectively. WBGT values were higher than the permissible level provided by ISO7243 in all farming activities. Maximum value of WBGT was belonged to fertilizing activity (31.99 °C and the lowest value was for plowing (29.98 °C. ANOVA test results did not show a significant difference in WBGT at head, waist, and ankle height. The highest and lowest amount of productivity loss was estimated respectively for weeding and plowing activities. The total productivity loss for farming was calculated 69.3 percent in an hour which is due to high physical activity, working outdoor, with exposure to direct solar radiation, and consequent heat stress imposed to workers. Conclusion: Productivity is a factor which is affected by the workplace heat stress. According to results of the present research, the amount of productivity is reduced

Language production in a shared task: Cumulative semantic interference from self- and other-produced context words

NARCIS (Netherlands)

Hoedemaker, R.S.; Ernst, J.; Meyer, A.S.; Belke, E.

2017-01-01

This study assessed the effects of semantic context in the form of self-produced and other-produced words on subsequent language production. Pairs of participants performed a joint picture naming task, taking turns while naming a continuous series of pictures. In the single-speaker version of this

Impact of task design on task performance and injury risk: case study of a simulated drilling task.

Science.gov (United States)

Alabdulkarim, Saad; Nussbaum, Maury A; Rashedi, Ehsan; Kim, Sunwook; Agnew, Michael; Gardner, Richard

2017-06-01

Existing evidence is limited regarding the influence of task design on performance and ergonomic risk, or the association between these two outcomes. In a controlled experiment, we constructed a mock fuselage to simulate a drilling task common in aircraft manufacturing, and examined the effect of three levels of workstation adjustability on performance as measured by productivity (e.g. fuselage completion time) and quality (e.g. fuselage defective holes), and ergonomic risk as quantified using two common methods (rapid upper limb assessment and the strain index). The primary finding was that both productivity and quality significantly improved with increased adjustability, yet this occurred only when that adjustability succeeded in reducing ergonomic risk. Supporting the inverse association between ergonomic risk and performance, the condition with highest adjustability created the lowest ergonomic risk and the best performance while there was not a substantial difference in ergonomic risk between the other two conditions, in which performance was also comparable. Practitioner Summary: Findings of this study supported a causal relationship between task design and both ergonomic risk and performance, and that ergonomic risk and performance are inversely associated. While future work is needed under more realistic conditions and a broader population, these results may be useful for task (re)design and to help cost-justify some ergonomic interventions.

Investigating the possibility of a syntactic impairment in the semantic variant of PPA using a constrained production task: Preliminary findings

Directory of Open Access Journals (Sweden)

Jennifer Cupit

2015-04-01

Full Text Available In the semantic variant of primary progressive aphasia (svPPA, syntactic skills are generally thought to be preserved, while in the non-fluent variant (nfvPPA syntactic impairment is a core diagnostic feature (Gorno-Tempini et al., 2011. There are, however, some indications in the literature that syntactic processing may not be entirely normal in svPPA. Most studies of syntactic production in svPPA have used unconstrained tasks and have found no syntactic impairment (e.g., Bird et al., 2000; Kave et al., 2007. In the two published studies that have found a syntactic impairment in svPPA, one used a constrained task (Benedet et al., 2006, and the other (Meteyard & Patterson, 2009 did not. However, the authors of the latter article suggested that the observed syntactic errors were subtle. They also suggested that a syntactic impairment in svPPA might not be observed in spontaneous language samples due to an overreliance on simpler structures. In the current study, we used a constrained sentence production task to compare the syntactic abilities of individuals with nfvPPA, svPPA and healthy controls longitudinally, to investigate the existence of a syntactic impairment in the different PPA variants. We predicted that by using a constrained task we would observe a syntactic impairment in both variants of PPA. We tested 18 participants with nfvPPA, 13 with svPPA and 23 control participants. They were tested up to three separate times, with approximately one year between sessions. Groups were matched on age and years of education. The patient groups were matched on Mini Mental State Examination score (Folstein, Folstein & McHugh, 1975 and estimated time post onset of initial symptoms, but the nfvPPA group scored higher than the svPPA group on the Boston Naming Test (Kaplan, Goodglass, & Weintraub, 2001. We used the sentence production task from Caplan and Hanna (1998 to elicit active, passive, dative and dative-passive sentences. A mixed ANOVA (Group X

Study of alternative strategies to the task clarification activity of the market-pull product development process model

OpenAIRE

Motte, Damien

2009-01-01

A very large majority of the current product development process models put forward in textbooks present a homogenous structure, what Ulrich & Eppinger [1] call the market-pull model, presented as a generic one, while other possible product development process models are merely seen as variants. This paper focuses on the task clarification and derived activities (mainly the systematic search for customer needs through market study and the supplementary development costs it entails) and in...

Task-failure-driven rebalancing of disassembly lines

OpenAIRE

Altekin, Fatma Tevhide; Akkan, Can

2011-01-01

Many reverse-logistics systems that collect and reprocess end-of-life products require a disassembly stage. The nature of variability in incoming products, and damages, which are more likely to occur during disassembly than assembly, create a significant uncertainty in disassembly tasks, namely, possibility of failed tasks. Such failures may lead to some successor tasks being infeasible, which changes work contents of downstream stations. To improve the profitability of such a disassembly lin...

A strategy for improving worker satisfaction and job attitudes in a repetitive industrial task: application of production standards and performance feedback.

Science.gov (United States)

Shikdar, Ashraf A; Das, Biman

2003-04-15

Worker satisfaction improved significantly as a consequence of the provision of the assigned and participative standards with performance feedback in a repetitive industrial production task. The maximum improvement in worker satisfaction was found for the participative standard and feedback condition. Only this condition had a significant positive effect on worker job attitudes. Monetary incentive, when provided with an assigned or participative standard with feedback, added no incremental worker satisfaction or job attitudes gain. The participative standard with feedback condition emerges as the optimum strategy for improving worker satisfaction and job attitudes in a repetitive industrial production task.

Product Evaluation Task Force Phase Two report for centrifuge cake

International Nuclear Information System (INIS)

Francis, A.J.; Davies, A.

1990-01-01

It has been proposed that all Intermediate Level Wastes arising at Sellafield should be encapsulated prior to ultimate disposal. The Product Evaluation Task Force (PETF) was set up to investigate possible encapsulants and to produce and adequate data base to justify the preferred matrices. Three possible types of encapsulants for Centrifuge Cake;- Inorganic cements, Polymer cements, and Polymers, are evaluated using the Kepner Tregoe decision analysis technique. This technique provides a methodology for scoring and ranking alternative options and evaluating any risks associated with an option. The analysis shows that for all four stages of waste management operations ie. Storage Transport, handling and emplacement Disposal, and Process, cement matrices are considerably superior to other potential matrices. A matrix, consisting of nine parts Blast Furnace Slag (BFS) to one part Ordinary Portland Cement (OPC) is recommended as the preferred matrix for Phase 3 studies on Centrifuge Cake. (author)

Effects of Task Complexity, Task Conditions, and Task Difficulty on the Grammatical Accuracy of EFL Learners in Written Discourse

Directory of Open Access Journals (Sweden)

Saeideh Ahangari

2012-11-01

Full Text Available Different methods of language teaching have tried to help EFL learners to develop good language skills based on their various perspectives. Research findings have underscored the effect of using task types in promoting language skills in terms of accuracy in written discourse. Therefore, this study set out to investigate whether there is an evidence of correct use of simple past tense (Accuracy based on Task Complexity (Task type :Here-and now & There-and-then,Task Conditions (Gender: Male & Female, and Task Difficulty (Proficiency: Lower-intermediate & Intermediate. Sixty Iranian English learners in a language institute participated in the study and were assigned to four groups of lower-intermediate male, lower-intermediate female, intermediate male and intermediate female. Initial homogeneity of the groups was verified using two general proficiency tests; KET for lower-intermediate and PET for intermediate. All groups in here-and-now task type were asked to write a story using simple past based on a picture strip while for there-and-then task type the participants were supposed to write about their last birthday. The results from paired samples t-test, independent samples t-test and two-way ANOVA analysis of the written data revealed significant differences in performing task types, at different proficiency levels and interaction between them. The findings have significant pedagogical implications for EFL learners to understand the relationship among Task Complexity,Task Conditions, Task Difficulty and L2 written production leading to various degrees of Accuracy.

Kokkos' Task DAG Capabilities.

Energy Technology Data Exchange (ETDEWEB)

Edwards, Harold C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ibanez, Daniel Alejandro [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

This report documents the ASC/ATDM Kokkos deliverable "Production Portable Dy- namic Task DAG Capability." This capability enables applications to create and execute a dynamic task DAG ; a collection of heterogeneous computational tasks with a directed acyclic graph (DAG) of "execute after" dependencies where tasks and their dependencies are dynamically created and destroyed as tasks execute. The Kokkos task scheduler executes the dynamic task DAG on the target execution resource; e.g. a multicore CPU, a manycore CPU such as Intel's Knights Landing (KNL), or an NVIDIA GPU. Several major technical challenges had to be addressed during development of Kokkos' Task DAG capability: (1) portability to a GPU with it's simplified hardware and micro- runtime, (2) thread-scalable memory allocation and deallocation from a bounded pool of memory, (3) thread-scalable scheduler for dynamic task DAG, (4) usability by applications.

Information Interaction Criteria Among Students in Process of Task-Based Information Searching (Role of Objective Complexity and Type of Product

Directory of Open Access Journals (Sweden)

Marziyeh Saeedizadeh

2016-08-01

Full Text Available Purpose:  human-information interactions must be considered in order to be able to interactively design Information Retrieval Systems (IRS. In this regard, study of users’ interactions must be based on their socio-cultural context (specifically work tasks. Accordingly, this paper aims to explore the use of information-interaction criteria among students in the information searching process according to different kinds of their work tasks.  Methodology: This research is applied qualitative method using exploratory study. The research population consisted of MSc students of Ferdowsi university of Mashhad enrolled in 2012-13  academic year. In 3 stages of sampling (random stratified, quota, and voluntary sampling, 30 cases were selected. Each of these cases searched 6 different types of simulated work tasks. Interaction criteria were extracted ? Content analysis of aloud thinking reports. Validity of tools was verified through Faculties of KIS at Ferdowsi university of Mashhad. Also,0.78  Kripendorff’s alpha ratio based on an agreement between the inter – coder indicates the Dependability  of content analysis. Findings: The findings show that in addition to ‘topic’ criteria, other interaction criteria impact on information- interaction of users, such as: ‘search results ranking’, ‘domain knowledge of user’, ‘layout’, ‘type of information resource’ and etc. based on the level of objective complexity and product of  work tasks, information-interaction criteria change. Conclusion: the users pay attention to different information-interaction criteria in process of information searching, considering to variety of work tasks (level of objective complexity and product. So, it is necessary to pay attention to work task characteristics in order to design interactive and personalized IR systems.

The Effects of Simultaneous Use of Careful Online Planning and Task Repetition on Accuracy, Complexity, and Fluency in EFL Learners' Oral Production

Science.gov (United States)

Ahmadian, Mohammad Javad; Tavakoli, Mansoor

2011-01-01

This article reports on a study that was primarily aimed at investigating the effects of simultaneous use of careful online planning and task repetition on accuracy, complexity, and fluency in the oral production of learners of English as a foreign language (EFL). The effects of four planning and task repetition conditions (i.e. careful online…

Transverse mode selection in vertical-cavity surface-emitting lasers via deep impurity-induced disordering

Science.gov (United States)

O'Brien, Thomas R.; Kesler, Benjamin; Dallesasse, John M.

2017-02-01

Top emission 850-nm vertical-cavity surface-emitting lasers (VCSELs) demonstrating transverse mode selection via impurity-induced disordering (IID) are presented. The IID apertures are fabricated via closed ampoule zinc diffusion. A simple 1-D plane wave model based on the intermixing of Group III atoms during IID is presented to optimize the mirror loss of higher-order modes as a function of IID strength and depth. In addition, the impact of impurity diffusion into the cap layer of the lasers is shown to improve contact resistance. Further investigation of the mode-dependent characteristics of the device imply an increase in the thermal impedance associated with the fraction of IID contained within the oxide aperture. The optimization of the ratio of the IID aperture to oxide aperture is experimentally determined. Single fundamental mode output of 1.6 mW with 30 dBm side mode suppression ratio is achieved by a 3.0 μm oxide-confined device with an IID aperture of 1.3 μm indicating an optimal IID aperture size of 43% of the oxide aperture.

Sustainable hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Block, D.L.; Linkous, C.; Muradov, N.

1996-01-01

This report describes the Sustainable Hydrogen Production research conducted at the Florida Solar Energy Center (FSEC) for the past year. The report presents the work done on the following four tasks: Task 1--production of hydrogen by photovoltaic-powered electrolysis; Task 2--solar photocatalytic hydrogen production from water using a dual-bed photosystem; Task 3--development of solid electrolytes for water electrolysis at intermediate temperatures; and Task 4--production of hydrogen by thermocatalytic cracking of natural gas. For each task, this report presents a summary, introduction/description of project, and results.

Sparteine monooxygenase in brain and liver: Identified by the dopamine uptake blocker [3H]GBR-12935

International Nuclear Information System (INIS)

Kalow, W.; Tyndale, R.F.; Niznik, H.B.; Inaba, T.

1990-01-01

P450IID6 (human sparteine monooxygenase) metabolizes many drugs including neuroleptics, antidepressants, and beta-blockers. The P450IID6 exists in human, bovine, rat and canine brains, but in very low quantities causing methodological difficulties in its assessment. Work with [ 3 H]GBR-12935; 1-[2-(diphenylmethoxy) ethyl]-4-(3-phenyl propyl) piperazine has shown that it binds a neuronal/hepatic protein with high affinity (∼7nM) and a rank order of inhibitory potency suggesting that the binding protein is cytochrome P450IID6. The binding was used to predict that d-amphetamine and methamphetamine would interact with P450IID6. Inhibition studies indicated that these compounds were competitive inhibitors of P450IID6. Haloperidol (HAL) and it's metabolite hydroxy-haloperidol (RHAL) are both competitive inhibitors of P450IID6 activity and were found to inhibit [ 3 H]GBR-12935 binding. K i values of twelve compounds (known to interact with the DA transporter or P450IID6) for [ 3 H]GRB-12935 binding and P450IID6 activity. The techniques are now available for measurements of cytochrome P450IID6 in healthy and diseased brain/liver tissue using radio-receptor binding assay techniques with [ 3 H]GBR-12935

Rules and more rules: the effects of multiple tasks, extensive training, and aging on task-switching performance.

Science.gov (United States)

Buchler, Norbou G; Hoyer, William J; Cerella, John

2008-06-01

Task-switching performance was assessed in young and older adults as a function of the number of task sets to be actively maintained in memory (varied from 1 to 4) over the course of extended training (5 days). Each of the four tasks required the execution of a simple computational algorithm, which was instantaneously cued by the color of the two-digit stimulus. Tasks were presented in pure (task set size 1) and mixed blocks (task set sizes 2, 3, 4), and the task sequence was unpredictable. By considering task switching beyond two tasks, we found evidence for a cognitive control system that is not overwhelmed by task set size load manipulations. Extended training eliminated age effects in task-switching performance, even when the participants had to manage the execution of up to four tasks. The results are discussed in terms of current theories of cognitive control, including task set inertia and production system postulates.

UN-ECE task force: 'by-product utilization from stationary installations'

International Nuclear Information System (INIS)

Hackl, A. E.; Zehetner, G.

1996-09-01

The task force has concluded as followed: Major sources of by-products considered in this report from stationary installations are large scale firing installations, waste incineration, upgrading processes and utilization in iron and steel, aluminium and copper industry, and the pulp and paper industry. The share of each sector source to the total amount of by-products generated differs significantly in the participating countries. State of the art processes as described in the report take account of the need for integrated pollution prevention and control. In particular the requirements set out in the Convention on Long Range Transboundary Air Pollution can still be satisfied when applying these state of the art processes. The report shows that a number of techniques for avoidance, reduction and/or utilization of by-products are in commercial operation in the branches discussed. They can therefore be considered to be best available. For some special by-products technical processes for the treatment are still in development and are not yet state-of-the-art. The implementation of the already proven techniques varies considerably in the different ECE-countries. This is mainly due to the following circumstances: differences in the design and stringency of legal regulations, availability of landfilling sites, costs of disposal, differences in industrial structure. Problems with by-product utilization originate mainly from: a) from a loss of international competitiveness of the respective industrial sector, if the reduction of the amount of by-products or their utilization leads to higher costs than conventional processes; b) from quality standards for materials which are inadequate for secondary raw materials thus creating acceptance problems of these materials. C) In some cases incineration and/or thermal recycling processes generate PCDD/F. quantities produces may be capable of reduction by means of process modification. If, however PCDD/F is released to the

Mitigating Backgrounds with a Novel Thin-Film Cathode in the DRIFT-IId Dark Matter Detector

Science.gov (United States)

Miller, Eric H.

The nature of dark matter, which comprises 85% of the matter density in the universe, is a major outstanding question in physics today. The standard hypothesis is that the dark matter is a new weakly interacting massive particle, which is present throughout the galaxy. These particles could interact within detectors on Earth, producing low-energy nuclear recoils. Two distinctive signatures arise from the solar motion through the galaxy. The DRIFT experiment aims to measure one of these, the directional signature that is based on the sidereal modulation of the nuclear recoil directions. Although DRIFT has demonstrated its capability for detecting this signature, it has been plagued by a large number of backgrounds that have limited its reach. The focus of this thesis is on characterizing these backgrounds and describing techniques that have essentially eliminated them. The background events in the DRIFT-IId detector are predominantly caused by alpha decays on the central cathode in which the alpha particles completely or partially absorbed by the cathode material. This thesis describes the installation a 0.9 mum thick aluminized-mylar cathode as a way to reduce the probability of producing these backgrounds. We study three generations of cathode (wire, thin-film, and radiologically clean thin-film) with a focus on identifying and quantifying the sources of alpha decay backgrounds, as well as their contributions to the background rate in the detector. This in-situ study is based on alpha range spectroscopy and the determination of the absolute alpha detection efficiency. The results for the final radiologically clean version of the cathode give a contamination of 3.3 +/- 0.1 ppt 234U and 73 +/- 2 ppb 238U, and an efficiency for rejecting an RPR from an alpha decay that is a factor 70 +/- 20 higher than for the original wire cathode. Along with other background reduction measures, the thin-film cathode has reduced the observed background rate from 130/day to 1.7/day

a Task-Driven Disaster Data Link Approach

Science.gov (United States)

Qiu, L. Y.; Zhu, Q.; Gu, J. Y.; Du, Z. Q.

2015-08-01

With the rapid development of sensor networks and Earth observation technology, a large quantity of disaster-related data is available, such as remotely sensed data, historic data, cases data, simulation data, disaster products and so on. However, the efficiency of current data management and service systems has become increasingly serious due to the task variety and heterogeneous data. For emergency task-oriented applications, data searching mainly relies on artificial experience based on simple metadata index, whose high time-consuming and low accuracy cannot satisfy the requirements of disaster products on velocity and veracity. In this paper, a task-oriented linking method is proposed for efficient disaster data management and intelligent service, with the objectives of 1) putting forward ontologies of disaster task and data to unify the different semantics of multi-source information, 2) identifying the semantic mapping from emergency tasks to multiple sources on the basis of uniform description in 1), 3) linking task-related data automatically and calculating the degree of correlation between each data and a target task. The method breaks through traditional static management of disaster data and establishes a base for intelligent retrieval and active push of disaster information. The case study presented in this paper illustrates the use of the method with a flood emergency relief task.

a Task-Oriented Disaster Information Correlation Method

Science.gov (United States)

Linyao, Q.; Zhiqiang, D.; Qing, Z.

2015-07-01

With the rapid development of sensor networks and Earth observation technology, a large quantity of disaster-related data is available, such as remotely sensed data, historic data, case data, simulated data, and disaster products. However, the efficiency of current data management and service systems has become increasingly difficult due to the task variety and heterogeneous data. For emergency task-oriented applications, the data searches primarily rely on artificial experience based on simple metadata indices, the high time consumption and low accuracy of which cannot satisfy the speed and veracity requirements for disaster products. In this paper, a task-oriented correlation method is proposed for efficient disaster data management and intelligent service with the objectives of 1) putting forward disaster task ontology and data ontology to unify the different semantics of multi-source information, 2) identifying the semantic mapping from emergency tasks to multiple data sources on the basis of uniform description in 1), and 3) linking task-related data automatically and calculating the correlation between each data set and a certain task. The method goes beyond traditional static management of disaster data and establishes a basis for intelligent retrieval and active dissemination of disaster information. The case study presented in this paper illustrates the use of the method on an example flood emergency relief task.

Cauldrons: An Abstraction for Concurrent Problems Solving. Revision.

Science.gov (United States)

1986-09-01

PROGRAM ELEMENT. PROJECT. TASK Artificial Inteligence Laboratory ARtA G WORK UNIT NUMVERS S 545 Technology Square etJ Cambridge, MA 02139 TIM II...D-11194 12611 CAU1,LDRONS: AN ROSTRACTION FOR CONCURRENT PROBLEMS1/ RSOLVING REYISION(U) MASSACHUSETTS INST OF TECHCANIRIDGE ARTIFICIAL INTELLIGENCE...is described, accompanied by cxanmple of their application to various domains. ’lhis report describes research done at both the MIT Artificial

Language production in a shared task: Cumulative semantic interference from self- and other-produced context words

OpenAIRE

Hoedemaker, R.; Ernst, J.; Meyer, A.; Belke, E.

2017-01-01

This study assessed the effects of semantic context in the form of self-produced and other-produced words on subsequent language production. Pairs of participants performed a joint picture naming task, taking turns while naming a continuous series of pictures. In the single-speaker version of this paradigm, naming latencies have been found to increase for successive presentations of exemplars from the same category, a phenomenon known as Cumulative Semantic Interference (CSI). As expected, th...

Snapshots of mathematics teacher noticing during task design

Science.gov (United States)

Choy, Ban Heng

2016-09-01

Designing a mathematically worthwhile task is critical for promoting students' reasoning. To improve task design skills, teachers often engage in collaborative lesson planning activities such as lesson study. However, to learn from the process of lesson study, it is important for teachers to notice productively the concepts, students' confusion and the design of the task. But what researchers mean by productive noticing varies. In this article, I present the FOCUS Framework which highlights two characteristics of productive noticing: having an explicit focus for noticing and focusing noticing through pedagogical reasoning. Using these two characteristics, I develop snapshots of noticing as a representation of practice to present a fine-grained analysis of teacher noticing. Through vignettes of teachers discussing the design of a task to teach fractions, I illustrate how two teachers' noticing can be analysed and represented using snapshots of noticing. To conclude, I highlight what snapshots of noticing tell us about a teacher's noticing and suggest ways to use these snapshots in future studies of noticing.

Genotyping of Trypanosoma cruzi Sublineage in Human Samples from a North-East Argentina Area by Hybridization with DNA Probes and Specific Polymerase Chain Reaction (PCR)

Science.gov (United States)

Diez, Cristina; Lorenz, Virginia; Ortiz, Silvia; Gonzalez, Verónica; Racca, Andrea; Bontempi, Iván; Manattini, Silvia; Solari, Aldo; Marcipar, Iván

2010-01-01

We have evaluated blood samples of chronic and congenital Trypanosoma cruzi-infected patients from the city of Reconquista located in the northeast of Argentina where no information was previously obtained about the genotype of infecting parasites. Fourteen samples of congenital and 19 chronical patients were analyzed by hybridization with DNA probes of minicircle hypervariable regions (mHVR). In congenital patients, 50% had single infections with TcIId, 7% single infections with TcIIe, 29% mixed infections with TcIId/e, and 7% had mixed infections with TcIId/b and 7% TcIId/b, respectively. In Chronical patients, 52% had single infections with TcIId, 11% single infections with TcIIe, 26% had mixed infections with TcIId/e, and 11% had non-identified genotypes. With these samples, we evaluated the minicircle lineage-specific polymerase chain reaction assay (MLS-PCR), which involves a nested PCR to HVR minicircle sequences and we found a correlation with hybridization probes of 96.4% for TcIId and 54.8% for TcIIe. PMID:20064998

Student Language Production, Second Language Tasks, and Instructional Scaffolding in an English-Based Curriculum in Vietnam: Realities and Hopes

Science.gov (United States)

Pham, Thuong T. M.

2017-01-01

This dissertation investigates L2 student language production, task-based instruction, and teachers' scaffolding strategies in two special EFL classes in a Vietnamese university. Two English teachers and 73 students were studied as they participated in a nationwide educational project known as the Advanced Curriculum (AC), an initiative launched…

Heuristic for Task-Worker Assignment with Varying Learning Slopes

Directory of Open Access Journals (Sweden)

Wipawee Tharmmaphornphilas

2010-04-01

Full Text Available Fashion industry has variety products, so the multi-skilled workers are required to improve flexibility in production and assignment. Generally the supervisor will assign task to the workers based on skill and skill levels of worker. Since in fashion industry new product styles are launched more frequently and the order size tends to be smaller, the workers always learn when the raw material and the production process changes. Consequently they require less time to produce the succeeding units of a task based on their learning ability. Since the workers have both experience and inexperience workers, so each worker has different skill level and learning ability. Consequently, the assignment which assumed constant skill level is not proper to use. This paper proposes a task-worker assignment considering worker skill levels and learning abilities. Processing time of each worker changes along production period due to a worker learning ability. We focus on a task-worker assignment in a fashion industry where tasks are ordered in series; the number of tasks is greater than the number of workers. Therefore, workers can perform multiple assignments followed the precedence restriction as an assembly line balancing problem. The problem is formulated in an integer linear programming model with objective to minimize makespan. A heuristic is proposed to determine the lower bound (LB and the upper bound (UB of the problem and the best assignment is determined. The performance of the heuristic method is tested by comparing quality of solution and computational time to optimal solutions.

Students with Attention Deficit Disorder Carrying out Tasks of Reading Comprehension and Text Production: A Comparative Study in 4th-Grade Students of Primary Education in Chile

OpenAIRE

Fabián Andrés Inostroza-Inostroza

2017-01-01

The present article aims to compare the performance in students with Attention Deficit Disorder to those who do not present it, in tasks of reading comprehension and text production carried out by students attending the fourth grade of primary education. This quantitative, non-experimental comparative study aims to provide evidence regarding the way in which this condition limits the learning outcomes in the tasks of comprehension and production of texts, language, and communication. One the ...

From Metalinguistic Instruction to Metalinguistic Knowledge, and from Metalinguistic Knowledge to Performance in Error Correction and Oral Production Tasks

Science.gov (United States)

Serrano, Raquel

2011-01-01

The purpose of this study is to analyse the effect of metalinguistic instruction on students' metalinguistic knowledge on the one hand, and on students' performance in metalinguistic and oral production tasks on the other hand. Two groups of primary school students learning English as a foreign language were chosen. One of them (Rule group) was…

Lexical Access in L2 Speech Production: a controlled serial search task

Directory of Open Access Journals (Sweden)

Gicele Vergine Vieira

2017-09-01

Full Text Available When it comes to lexical access in L2 speech production, working memory (WM seems to play a central role as for less automatized procedures require more WM capacity to be executed (Prebianca, 2007. With that in mind, this paper aims at claiming that bilingual lexical access qualifies as a controlled serial strategic search task susceptible to individual differences in WM capacity. Evidence in support of such claim is provided by the results of AUTHOR's (2010 study conducted so as to investigate the relationship between L2 lexical access, WMC and L2 proficiency. AUTHOR's (2010 findings indicate that bilingual lexical access entails underlying processes such as cue generation, set delimitation, serial search and monitoring, which to be carried out, require the allocation of attention. Attention is limited and, as a result, only higher spans were able to perform these underlying processes automatically.

Advantages and disadvantages of intraoperative language tasks in awake surgery: a three-task approach for prefrontal tumors.

Science.gov (United States)

Rofes, A; Spena, G; Miozzo, A; Fontanella, M M; Miceli, G

2015-12-01

Multidisciplinary efforts are being made to provide surgical teams with sensitive and specific tasks for language mapping in awake surgery. Researchers and clinicians have elaborated different tasks over time. A fair amount of work has been directed to study the neurofunctional correlates of some of these tasks, and there is recent interest in their standardization. However, little discussion exists on the advantages and disadvantages that each task poses from the perspective of the cognitive neuroscience of language. Such an approach may be a relevant step to assess task validity, to avoid using tasks that tap onto similar processes, and to provide patients with a surgical treatment that ensures maximal tumor resection while avoiding postoperative language deficits. An understanding of the language components that each task entails may also be relevant to improve the current assessments and the ways in which tasks are administered, and to disentangle neurofunctional questions. We reviewed 17 language mapping tasks that have been used in awake surgery. Overt production tasks have been a preferred choice over comprehension tasks. Tasks tapping lexico-semantic processes, particularly object-naming, maintain their role as gold standards. Automated speech tasks are used to detect speech errors and to set the amplitude of the stimulator. Comprehension tasks, reading and writing tasks, and tasks that assess grammatical aspects of language may be regularly administered in the near future. We provide examples of a three-task approach we are administering to patients with prefrontal lesions. We believe that future advances in this area are contingent upon reviewing gold standards and introducing new assessment tools.

Diagnosing norovirus-associated infectious intestinal disease using viral load

Directory of Open Access Journals (Sweden)

Tam Clarence C

2009-05-01

Full Text Available Abstract Background Reverse transcription-polymerase chain reaction (RT-PCR is the main method for laboratory diagnosis of norovirus-associated infectious intestinal disease (IID. However, up to 16% of healthy individuals in the community, with no recent history of IID, may be RT-PCR positive; so it is unclear whether norovirus is actually the cause of illness in an IID case when they are RT-PCR positive. It is important to identify the pathogen causing illness in sporadic IID cases, for clinical management and for community based incidence studies. The aim of this study was to investigate how faecal viral load can be used to determine when norovirus is the most likely cause of illness in an IID case. Methods Real-time RT-PCR was used to determine the viral load in faecal specimens collected from 589 IID cases and 159 healthy controls, who were infected with genogroup II noroviruses. Cycle threshold (Ct values from the real-time RT-PCR were used as a proxy measure of viral load. Receiver-operating characteristic (ROC analysis was used to identify a cut-off in viral load for attributing illness to norovirus in IID cases. Results One hundred and sixty-nine IID cases and 159 controls met the inclusion criteria for the ROC analysis. The optimal Ct value cut-off for attributing IID to norovirus was 31. The same cut-off was selected when using healthy controls, or IID cases who were positive by culture for bacterial pathogens, as the reference negative group. This alternative reference negative group can be identified amongst specimens routinely received in clinical virology laboratories. Conclusion We demonstrated that ROC analysis can be used to select a cut-off for a norovirus real time RT-PCR assay, to aid clinical interpretation and diagnose when norovirus is the cause of IID. Specimens routinely received for diagnosis in clinical virology laboratories can be used to select an appropriate cut-off. Individual laboratories can use this method to

Developmental course of conversational behaviour of children with 22q11.2 deletion syndrome and Williams syndrome

OpenAIRE

Van Den Heuvel, E.; Botting, N.; Boudewijns, I.; Manders, E.; Swillen, A.; Zink, I.

2017-01-01

This study investigated three conversational subskills in children with 22q11.2 deletion syndrome (22q11.2DS, n = 8, ages 7–13) and Williams syndrome (WS, n = 8, ages 6–12). We re-evaluated these subskills after 18 to 24 months and compared them to those of peers with idiopathic intellectual disability (IID) and IID and comorbid autism spectrum disorders (IID+ASD). Children with 22q11.2DS became less actively involved over time. Lower assertiveness than in children with IID was demonstrated. ...

Molecular Analysis of the Enteric Protozoa Associated with Acute Diarrhea in Hospitalized Children.

Science.gov (United States)

Boughattas, Sonia; Behnke, Jerzy M; Al-Ansari, Khalid; Sharma, Aarti; Abu-Alainin, Wafa; Al-Thani, Asma; Abu-Madi, Marawan A

2017-01-01

Pediatric diarrhea is a common cause of death among children under 5 years of age. In the current study, we investigated the frequency of intestinal parasites among 580 pediatric patients with chronic diarrhea. Parasitic protozoa (all species combined) were detected by molecular tools in 22.9% of the children and the most common parasite was Cryptosporidium spp. (15.1%). Blastocystis hominis was detected in 4.7%, Dientamoeba fragilis in 4%, Giardia duodenalis in 1.7%, and Entamoeba histolytica in 0.17%. Protozoan infections were observed among all regional groups, but prevalence was highest among Qatari subjects and during the winter season. Typing of Cryptosporidium spp. revealed a predominance of Cryptosporidium parvum in 92% of cases with mostly the IIdA20G1 subtype. Subtypes IIdA19G2, IIdA18G2, IIdA18G1, IIdA17G1, IIdA16G1, and IIdA14G1 were also detected. For Cryptosporidium hominis , IbA10G2 and IbA9G3 subtypes were identified. This study provides supplementary information for implementing prevention and control strategies to reduce the burden of these pediatric protozoan infections. Further analyses are required to better understand the local epidemiology and transmission of Cryptosporidium spp. in Qatar.

Acquisition and production of skilled behavior in dynamic decision-making tasks

Science.gov (United States)

Kirlik, Alex

1990-01-01

Ongoing research investigating perceptual and contextual influences on skilled human performance in dynamic decision making environments is discussed. The research is motivated by two general classes of findings in recent decision making research. First, many studies suggest that the concrete context in which a task is presented has strong influences on the psychological processes used to perform the task and on subsequent performance. Second, studies of skilled behavior in a wide variety of task environments typically implicate the perceptual system as an important contributor to decision-making performance, either in its role as a mediator between the current decision context and stored knowledge, or as a mechanism capable of directly initiating activity through the development of a 'trained eye.' Both contextual and perceptual influences place limits on the ability of traditional utility-theoretic accounts of decision-making to guide display design, as variance in behavior due to contextual factors or the development of a perceptual skill is left unexplained. The author outlines a framework in which to view questions of perceptual and contextual influences on behavior and describe an experimental task and analysis technique which will be used to diagnose the possible role of perception in skilled decision making performance.

II!D I

African Journals Online (AJOL)

JHypertms 1995; 1J, 91:;'924. 4. Schwartz Gl, Strong Cc. Renal parenchyma! involvement in essential hypertension. Med. Clin Norlh Am 1987; 71, 843-858. 5. Kincaid-5mith P. Malignant hypertension. JHypertms 1991; ~ 893-899. 6. lsaacson C. Milne Fj, van Niekerk I, Kenyon MR, Mzamane DV. The rena1 histopathology of.

Regular Exercise Enhances Task-Based Industriousness in Laboratory Rats.

Directory of Open Access Journals (Sweden)

Nicholas C Laurence

Full Text Available Individuals vary greatly in their willingness to select and persist in effortful tasks, even when high-effort will knowingly result in high-reward. Individuals who select and successively complete effortful, goal-directed tasks can be described as industrious. Trying to increase one's industriousness is desirable from a productivity standpoint, yet intrinsically challenging given that effort expenditure is generally aversive. Here we show that in laboratory rats, a basic physical exercise regimen (20 min/day, five days/week is sufficient to increase industriousness across a battery of subsequent testing tasks. Exercised rats outperformed their non-exercised counterparts in tasks designed to tax effort expenditure, strategic decision-making, problem solving and persistence. These increases in performance led to quicker reward obtainment and greater reward gain over time, and could not be accounted for simply by increased locomotor activity. Our results suggest that a basic exercise regimen can enhance effortful goal-directed behaviour in goal-directed tasks, which highlights a potential productivity benefit of staying physically active.

A thermostable metal-tolerant laccase with bioremediation potential from a marine-derived fungus

Digital Repository Service at National Institute of Oceanography (India)

DeSouza-Ticlo, D.; Sharma, D.; Raghukumar, C.

their optimum pH and temperature). From these results, K cat and specificity constant of Lac IId with ABTS were derived (Das et al., 2001). Substrate specificity and inhibitors of Lac IId. Oxygen uptake during reaction of Lac IId with substrates, non... from Q 10 values between 60 o and 70 o C at this pH was 2.5 kJ mol -1 whereas from the Arrhenius plot, it was 8.15 kJ mol -1 . The K m , V max and K cat of Lac IId were compared using ABTS and syringaldazine; maximum specificity constant (K...

Effects of cues in a binary categorization task on dual-task performance, mental workload, and effort.

Science.gov (United States)

Botzer, Assaf; Meyer, Joachim; Parmet, Yisrael

2016-09-01

Binary cues help operators perform binary categorization tasks, such as monitoring for system failures. They may also allow them to attend to other tasks they concurrently perform. If the time saved by using cues is allocated to other concurrent tasks, users' overall effort may remain unchanged. In 2 experiments, participants performed a simulated quality control task, together with a tracking task. In half the experimental blocks cues were available, and participants could use them in their decisions about the quality of products (intact or faulty). In Experiment 1, the difficulty of tracking was constant, while in Experiment 2, tracking difficulty differed in the 2 halves of the experiment. In both experiments, participants reported on the NASA Task Load Index that cues improved their performance and reduced their frustration. Consequently, their overall score on mental workload (MWL) was lower with cues. They also reported, however, that cues did not reduce their effort. We conclude that cues and other forms of automation may support task performance and reduce overall MWL, but this will not necessarily mean that users will work less hard. Thus, effort and overall MWL should be evaluated separately, if one wants to obtain a full picture of the effects of automation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Better dual-task processing in simultaneous interpreters

Science.gov (United States)

Strobach, Tilo; Becker, Maxi; Schubert, Torsten; Kühn, Simone

2015-01-01

Simultaneous interpreting (SI) is a highly complex activity and requires the performance and coordination of multiple, simultaneous tasks: analysis and understanding of the discourse in a first language, reformulating linguistic material, storing of intermediate processing steps, and language production in a second language among others. It is, however, an open issue whether persons with experience in SI possess superior skills in coordination of multiple tasks and whether they are able to transfer these skills to lab-based dual-task situations. Within the present study, we set out to explore whether interpreting experience is associated with related higher-order executive functioning in the context of dual-task situations of the Psychological Refractory Period (PRP) type. In this PRP situation, we found faster reactions times in participants with experience in simultaneous interpretation in contrast to control participants without such experience. Thus, simultaneous interpreters possess superior skills in coordination of multiple tasks in lab-based dual-task situations. PMID:26528232

Non-Asymptotic Oracle Inequalities for the High-Dimensional Cox Regression via Lasso.

Science.gov (United States)

Kong, Shengchun; Nan, Bin

2014-01-01

We consider finite sample properties of the regularized high-dimensional Cox regression via lasso. Existing literature focuses on linear models or generalized linear models with Lipschitz loss functions, where the empirical risk functions are the summations of independent and identically distributed (iid) losses. The summands in the negative log partial likelihood function for censored survival data, however, are neither iid nor Lipschitz.We first approximate the negative log partial likelihood function by a sum of iid non-Lipschitz terms, then derive the non-asymptotic oracle inequalities for the lasso penalized Cox regression using pointwise arguments to tackle the difficulties caused by lacking iid Lipschitz losses.

A Task-Based Approach to Organization: Knowledge, Communication and Structure

OpenAIRE

Luis Garicano; Yanhui Wu

2010-01-01

We bridge a gap between organizational economics and strategy research by developing a task-based approach to analyze organizational knowledge, process and structure, and deriving testable implications for the relation between production and organizational structure. We argue that organization emerges to integrate disperse knowledge and to coordinate talent in production and is designed to complement the limitations of human ability. The complexity of the tasks undertaken determines the optim...

Exploring the Relationship of Task Performance and Physical and Cognitive Fatigue During a Daylong Light Precision Task.

Science.gov (United States)

Yung, Marcus; Manji, Rahim; Wells, Richard P

2017-11-01

Our aim was to explore the relationship between fatigue and operation system performance during a simulated light precision task over an 8-hr period using a battery of physical (central and peripheral) and cognitive measures. Fatigue may play an important role in the relationship between poor ergonomics and deficits in quality and productivity. However, well-controlled laboratory studies in this area have several limitations, including the lack of work relevance of fatigue exposures and lack of both physical and cognitive measures. There remains a need to understand the relationship between physical and cognitive fatigue and task performance at exposure levels relevant to realistic production or light precision work. Errors and fatigue measures were tracked over the course of a micropipetting task. Fatigue responses from 10 measures and errors in pipetting technique, precision, and targeting were submitted to principal component analysis to descriptively analyze features and patterns. Fatigue responses and error rates contributed to three principal components (PCs), accounting for 50.9% of total variance. Fatigue responses grouped within the three PCs reflected central and peripheral upper extremity fatigue, postural sway, and changes in oculomotor behavior. In an 8-hr light precision task, error rates shared similar patterns to both physical and cognitive fatigue responses, and/or increases in arousal level. The findings provide insight toward the relationship between fatigue and operation system performance (e.g., errors). This study contributes to a body of literature documenting task errors and fatigue, reflecting physical (both central and peripheral) and cognitive processes.

Effects of task and category membership on representation stability

Directory of Open Access Journals (Sweden)

Céline Manetta

2011-01-01

Full Text Available This study examined the within-subject stability of 150 participants who performed both a sorting task and a property-generation task over multiple sessions, focusing on three concrete concept categories (food, animals and bathroom products. We hypothesized that (1 the within-subject stability would be higher in the sorting task than in the property-generation task and (2 the nature of the category would influence both the within-subject stability of the classification groups in the sorting task and the properties generated to define these groups. The results show that the within-subject stability of conceptual representations depends both on the task and on the nature of the category. The stability of the representations was greater in the sorting task than in the property-generation task and in the food category. These results are discussed from a longitudinal perspective.

Production of Modularised Product Systems

DEFF Research Database (Denmark)

Jacobsen, Peter

2004-01-01

but a solution. Modularisation is one tool used in designing the products. Designing and controlling a production system making customized products in an economical way is not an easy task. In order to fulfil the Lean and Agile manufacturing philosophies the production is often carried out in networks. Here...

Upper packing dimension of a measure and the limit distribution of ...

Indian Academy of Sciences (India)

.com. MS received 17 March 2009; revised 9 April 2009. Abstract. This article gives sufficient conditions for the limit distribution of products of i.i.d. 2 × 2 stochastic matrices to be continuous singular, when the support of the distribution of the ...

Concurrent multidisciplinary mechanical design based on design task analysis and knowledge sharing; Sekkei task bunseki to joho kyoyu ni yoru mechatronics kyocho sekkei

Energy Technology Data Exchange (ETDEWEB)

Kondo, K.; Ozawa, M.; Mori, T. [Toshiba Corp., Tokyo (Japan)

1999-09-01

We have developed a systematic design task planning method based on a design structure matrix(DSM) and a lumped model- based framework for knowledge sharing in a concurrent design environment as key techniques for developing higher quality products in a shorter design time. The DSM facilitates systematic analysis of dependencies among design tasks and optimization of the design process. The framework based on a lumped model description of mechanical systems enables concurrent and cooperative work among multidisciplinary designers at an early stage of the design process. In this paper, we also discuss the relationships between these techniques and the product development flow from product definition to detailed design. (author)

Form-based Approaches vs. Task-Based Approaches

Directory of Open Access Journals (Sweden)

Zahra Talebi

2015-07-01

Full Text Available This study aimed at investigating whether task-based approaches bear any superiority to that of more traditional ones evident in presentation-practice- and production phase .to fulfill the purpose of the study, the participants within the age range of 11-19, took part in the study. Following a pretest, treatment, and a posttest, the obtained data was analyzed using analysis of covariance (ANCOVA to examine the effects of the variables. The results of the analysis showed that participants in the PPP group did significantly better in the grammar recognition of the posttest than that of the task group. However, their counterparts in the task group gained better scores in the writing section of the test .this research study provided evidence in support of task proponents' claim in the merit of task-based activity in raising learners' implicit knowledge claiming to play the primary role in spontaneous speech.

The multi-task barge: a floating deep-sea production, storage and unloading unit, with surface production heads and drilling installations; La barge multifonctions: une unite flottante de production, de stockage et dechargement en eau profonde, avec tetes de production en surface et installations de forage

Energy Technology Data Exchange (ETDEWEB)

Valenchon, C; Rossig, J H [Bouygues Offshore (France); Pouget, G [Sedco-Forex (France); Biolley, F [Institut Francais du Petrole, 92 - Rueil-Malmaison (France)

1998-05-01

The multi-task barge is devoted to the exploitation of deep-sea fields in rather good conditions. It has been designed to bring together within a single installation, a production, storage and unloading unit and the necessary means for the drilling, the connecting and the work-over of wells. Thus submarine well-heads and well-head platforms are no longer needed. When the field configuration or the use of oriented drillings allows to group several wells together, the multi-task platform allows to use more economical surface production heads installed on steel rigid risers. This concept requires less investments thanks to less expensive drilling operations and restricted submarine installations, and to easier well operations and lower exploitation costs. Crude oil storage is ensured to up to about 2 millions of barrels. This paper presents the design aspects and the dynamical analysis of risers with the methods used. The tensioning and mooring system is examined and the advantages of the cylindrical float system is underlined and compared to the classical hydro-pneumatic systems. (J.S.) 11 refs.

Applied Railway Optimization in Production Planning at DSB-S-tog - Tasks, Tools and Challenges

DEFF Research Database (Denmark)

Clausen, Jens

2007-01-01

these conflicting goals. S-tog has therefore on the strategic level decided to use software with optimization capabilities in the planning processes. We describe the current status for each activity using optimization or simulation as a tool: Timetable evaluation, rolling stock planning, and crew scheduling...... to the customers, and has concurrently been met with demands for higher efficiency in the daily operation. The plans of timetable, rolling stock and crew must hence allow for a high level of customer service, be efficient, and be robust against disturbances of operations. It is a highly non-trivial task to meet....... In addition we describe on-going efforts in using mathematical models in activities such as timetable design and work-force planning. We also identify some organizatorial key factors, which have paved the way for extended use of optimization methods in railway production planning....

Language production in a shared task: Cumulative Semantic Interference from self- and other-produced context words.

Science.gov (United States)

Hoedemaker, Renske S; Ernst, Jessica; Meyer, Antje S; Belke, Eva

2017-01-01

This study assessed the effects of semantic context in the form of self-produced and other-produced words on subsequent language production. Pairs of participants performed a joint picture naming task, taking turns while naming a continuous series of pictures. In the single-speaker version of this paradigm, naming latencies have been found to increase for successive presentations of exemplars from the same category, a phenomenon known as Cumulative Semantic Interference (CSI). As expected, the joint-naming task showed a within-speaker CSI effect, such that naming latencies increased as a function of the number of category exemplars named previously by the participant (self-produced items). Crucially, we also observed an across-speaker CSI effect, such that naming latencies slowed as a function of the number of category members named by the participant's task partner (other-produced items). The magnitude of the across-speaker CSI effect did not vary as a function of whether or not the listening participant could see the pictures their partner was naming. The observation of across-speaker CSI suggests that the effect originates at the conceptual level of the language system, as proposed by Belke's (2013) Conceptual Accumulation account. Whereas self-produced and other-produced words both resulted in a CSI effect on naming latencies, post-experiment free recall rates were higher for self-produced than other-produced items. Together, these results suggest that both speaking and listening result in implicit learning at the conceptual level of the language system but that these effects are independent of explicit learning as indicated by item recall. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Task Repetition on Learners' Attention Orientation in L2 Oral Production

Science.gov (United States)

Fukuta, Junya

2016-01-01

Task repetition facilitates learners' performance, at least temporarily: Since learners are already familiar with the content of the task at the initial enactment, they are capable of focusing their attention on linguistic form during the following enactment. However, the analysis in previous studies treated various aspects of "form" as…

Designing the Widget: A Group Decision and Negotiation Task

Science.gov (United States)

Delise, Lisa A.; Mello, Abby L.

2017-01-01

The Widget design task is an in-class, experiential exercise that affords students the opportunity to develop interpersonal skills in group negotiation. Students engage in new product design in committees of two dyads where one dyad represents Consumer Research and the other represents Strategic Management. Task information creates different…

Synaptic conductances during interictal discharges in pyramidal neurons of rat entorhinal cortex

Directory of Open Access Journals (Sweden)

Dmitry V. Amakhin

2016-10-01

Full Text Available In epilepsy, the balance of excitation and inhibition underlying the basis of neural network activity shifts, resulting in neuronal network hyperexcitability and recurrent seizure-associated discharges. Mechanisms involved in ictal and interictal events are not fully understood, in particular, because of controversial data regarding the dynamics of excitatory and inhibitory synaptic conductances. In the present study, we estimated AMPAR-, NMDAR-, and GABAAR-mediated conductances during two distinct types of interictal discharge (IID in pyramidal neurons of rat entorhinal cortex in cortico-hippocampal slices. Repetitively emerging seizure-like events and IIDs were recorded in high extracellular potassium, 4-aminopyridine, and reduced magnesium-containing solution. An original procedure for estimating synaptic conductance during IIDs was based on the differences among the current-voltage characteristics of the synaptic components. The synaptic conductance dynamics obtained revealed that the first type of IID is determined by activity of GABAAR channels with depolarized reversal potential. The second type of IID is determined by the interplay between excitation and inhibition, with prominent early AMPAR and prolonged depolarized GABAAR and NMDAR-mediated components. The study then validated the contribution of these components to IIDs by intracellular pharmacological isolation. These data provide new insights into the mechanisms of seizures generation, development, and cessation.

Task analysis methods applicable to control room design review (CDR)

International Nuclear Information System (INIS)

Moray, N.P.; Senders, J.W.; Rhodes, W.

1985-06-01

This report presents the results of a research study conducted in support of the human factors engineering program of the Atomic Energy Control Board in Canada. It contains five products which may be used by the Atomic Enegy Control Board in relation to Task Analysis of jobs in CANDU nuclear power plants: 1. a detailed method for preparing for a task analysis; 2. a Task Data Form for recording task analysis data; 3. a detailed method for carrying out task analyses; 4. a guide to assessing alternative methods for performing task analyses, if such are proposed by utilities or consultants; and 5. an annotated bibliography on task analysis. In addition, a short explanation of the origins, nature and uses of task analysis is provided, with some examples of its cost effectiveness. 35 refs

Investigate-and-redesign tasks as a context for learning and doing science and technology: A study of naive, novice and expert high school and adult designers doing product comparisons and redesign tasks

Science.gov (United States)

Crismond, David Paul

This thesis studied high school students and adults with varying degrees of design experience doing two technology investigate-and-redesign (I&R) tasks. Each involved subjects investigating products, designing experiments to compare them fairly, and then redesigning the devices. A total of 25 pairs of subjects participated in this investigation and included naive and novice high school designers, as well as naive, novice, and expert adult designers. Subjects of similar age and design experience worked in same-gender teams and met for two 2-hour sessions. The essential research question of this thesis was: "What process skills and concepts do naive, novice and expert designers use and learn when investigating devices, designing experiments, and redesigning the devices?" Three methodologies were used to gather and analyze the data: clinical interviewing (Piaget, 1929/1960), protocol analysis (Ericsson & Simon, 1984) and interaction analysis (Jordan and Henderson, 1995). The thesis provides composite case-studies of 10 of the 50 test sessions, buttressed by descriptions of performance trends for all subjects. Given the small sample sizes involved, the findings are by necessity tentative and not supported by statistical analysis: (1) I&R activities are engaging, less time-intensive complements to design-and-build tasks, which involve simple mechanical devices and carry with them a host of potential "alternative understandings" in science and technology. Much gets learned during these tasks, more involving "device knowledge" and "device inquiry skills" than "big ideas" in science and technology. (2) Redesign tasks scaffold naive and novice designers to improved performance in the multidimensional and context-specific activity of design. The performances of naive and novice designers were more like that of expert designers when redesigning existing devices than when doing start-from-scratch designing. (3) Conceptual redesign involved more analysis- than synthesis

Coordiantion by using Product Specifications in Product Development

DEFF Research Database (Denmark)

Terkelsen, Søren Bendix

1997-01-01

This paper is based on a case study. It treats the coordination by generating product specifications in product development. This paper contains three very important aspects, which cause a need for coordination, and call attention to the coordination mechanisms. The three aspects are task...... uncertainty, task complexity, and dependencies between activities. If one want to select coordination mechanisms, which improve the performance in product development, it is very important to have a knowledge about these three aspects. In the following the aspects are identified in the literature...

Task Force report

International Nuclear Information System (INIS)

Anon.

1987-01-01

The International Task Force on Prevention of Nuclear Terrorism was formed in 1985 under the auspices of the Nuclear Control Institute. This report is a consensus report of the 26 task force members - all members not necessarily agreeing on every point and all wordings, but in each case a substantial majority did agree. First, the report defines the threat, then establishes the priorities. Short-term recommendations are presented on: (1) protecting nuclear weapons; (2) protecting nuclear materials; (3) protecting nuclear facilities; (4) intelligence programs; (5) civil liberties concerns; (6) controlling nuclear transfers; (7) US - Soviet cooperation; (8) arms control initiatives; (9) convention of physical protection of nuclear material; (10) role of emergency management programs; and (11) role of the media. Brief long-term recommendations are included on (1) international measures, and (2) emerging nuclear technologies. An Appendix, Production of Nuclear Materials Usable in Weapons is presented for further consideration (without recommendations)

Lost-time illness, injury and disability and its relationship with obesity in the workplace: A comprehensive literature review.

Science.gov (United States)

Nowrouzi, Behdin; Gohar, Basem; Nowrouzi-Kia, Behnam; Mintsopoulos, Victoria; McDougall, Alicia; Jordan, Gillian; Casole, Jennifer; Lariviere, Michel; Tremblay, Angelo

2016-01-01

The objective of this study was to conduct a literature review examining predictors of lost-time injury, illness and disability (IID) in the workplace, with a focus on obesity as a predictor, and to evaluate the relationship between obesity and losttime IID. The study objective was also to analyze workplace disability prevention and interventions aimed at encouraging a healthy lifestyle among employees and reducing obesity and IID, as well as to identify research gaps. The search was conducted in several major online databases. Articles included in the review were published in English in peer-reviewed journals between January 2003 and December 2014, and were found to be of good quality and of relevance to the topic. Each article was critically reviewed for inclusion in this study. Studies that focused on lost-time IID in the workplace were reviewed and summarized. Workers in overweight and obese categories are shown to be at a higher risk of workplace IID, are more likely to suffer from lost-time IID, and experience a slower recovery compared to workers with a healthy body mass index (BMI) score. Lost-time IID is costly to an employer and an employee; therefore, weight reduction may financially benefit both - workers and companies. It was found that some companies have focused on developing interventions that aid reduction of weight and the practice of active lifestyle among their employees. Int J Occup Med Environ Health 2016;29(5):749-766. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Exploiting Dynamics in robotic arms with repetitive tasks

NARCIS (Netherlands)

Plooij, M.C.

2015-01-01

Since the industrial revolution, machines have taken over many tasks from humans, increasing labor productivity and prosperity. In the 20th century, the introduction of robots created a second wave of automation, increasing the labor productivity even further. In order to create a third wave of

An Ontology to Improve Transparency in Case Definition and Increase Case Finding of Infectious Intestinal Disease: Database Study in English General Practice.

Science.gov (United States)

de Lusignan, Simon; Shinneman, Stacy; Yonova, Ivelina; van Vlymen, Jeremy; Elliot, Alex J; Bolton, Frederick; Smith, Gillian E; O'Brien, Sarah

2017-09-28

Infectious intestinal disease (IID) has considerable health impact; there are 2 billion cases worldwide resulting in 1 million deaths and 78.7 million disability-adjusted life years lost. Reported IID incidence rates vary and this is partly because terms such as "diarrheal disease" and "acute infectious gastroenteritis" are used interchangeably. Ontologies provide a method of transparently comparing case definitions and disease incidence rates. This study sought to show how differences in case definition in part account for variation in incidence estimates for IID and how an ontological approach provides greater transparency to IID case finding. We compared three IID case definitions: (1) Royal College of General Practitioners Research and Surveillance Centre (RCGP RSC) definition based on mapping to the Ninth International Classification of Disease (ICD-9), (2) newer ICD-10 definition, and (3) ontological case definition. We calculated incidence rates and examined the contribution of four supporting concepts related to IID: symptoms, investigations, process of care (eg, notification to public health authorities), and therapies. We created a formal ontology using ontology Web language. The ontological approach identified 5712 more cases of IID than the ICD-10 definition and 4482 more than the RCGP RSC definition from an initial cohort of 1,120,490. Weekly incidence using the ontological definition was 17.93/100,000 (95% CI 15.63-20.41), whereas for the ICD-10 definition the rate was 8.13/100,000 (95% CI 6.70-9.87), and for the RSC definition the rate was 10.24/100,000 (95% CI 8.55-12.12). Codes from the four supporting concepts were generally consistent across our three IID case definitions: 37.38% (3905/10,448) (95% CI 36.16-38.5) for the ontological definition, 38.33% (2287/5966) (95% CI 36.79-39.93) for the RSC definition, and 40.82% (1933/4736) (95% CI 39.03-42.66) for the ICD-10 definition. The proportion of laboratory results associated with a positive test

Neurophysiological Modulations of Non-Verbal and Verbal Dual-Tasks Interference during Word Planning.

Directory of Open Access Journals (Sweden)

Raphaël Fargier

Full Text Available Running a concurrent task while speaking clearly interferes with speech planning, but whether verbal vs. non-verbal tasks interfere with the same processes is virtually unknown. We investigated the neural dynamics of dual-task interference on word production using event-related potentials (ERPs with either tones or syllables as concurrent stimuli. Participants produced words from pictures in three conditions: without distractors, while passively listening to distractors and during a distractor detection task. Production latencies increased for tasks with higher attentional demand and were longer for syllables relative to tones. ERP analyses revealed common modulations by dual-task for verbal and non-verbal stimuli around 240 ms, likely corresponding to lexical selection. Modulations starting around 350 ms prior to vocal onset were only observed when verbal stimuli were involved. These later modulations, likely reflecting interference with phonological-phonetic encoding, were observed only when overlap between tasks was maximal and the same underlying neural circuits were engaged (cross-talk.

Neurophysiological Modulations of Non-Verbal and Verbal Dual-Tasks Interference during Word Planning.

Science.gov (United States)

Fargier, Raphaël; Laganaro, Marina

2016-01-01

Running a concurrent task while speaking clearly interferes with speech planning, but whether verbal vs. non-verbal tasks interfere with the same processes is virtually unknown. We investigated the neural dynamics of dual-task interference on word production using event-related potentials (ERPs) with either tones or syllables as concurrent stimuli. Participants produced words from pictures in three conditions: without distractors, while passively listening to distractors and during a distractor detection task. Production latencies increased for tasks with higher attentional demand and were longer for syllables relative to tones. ERP analyses revealed common modulations by dual-task for verbal and non-verbal stimuli around 240 ms, likely corresponding to lexical selection. Modulations starting around 350 ms prior to vocal onset were only observed when verbal stimuli were involved. These later modulations, likely reflecting interference with phonological-phonetic encoding, were observed only when overlap between tasks was maximal and the same underlying neural circuits were engaged (cross-talk).

Adaptive kanban control mechanism for a single-stage hybrid system

Science.gov (United States)

Korugan, Aybek; Gupta, Surendra M.

2002-02-01

In this paper, we consider a hybrid manufacturing system with two discrete production lines. Here the output of either production line can satisfy the demand for the same type of product without any penalties. The interarrival times for demand occurrences and service completions are exponentially distributed i.i.d. variables. In order to control this type of manufacturing system we suggest a single stage pull type control mechanism with adaptive kanbans and state independent routing of the production information.

JV Task 120 - Coal Ash Resources Research Consortium Research

Energy Technology Data Exchange (ETDEWEB)

Debra Pflughoeft-Hassett; Loreal Heebink; David Hassett; Bruce Dockter; Kurt Eylands; Tera Buckley; Erick Zacher

2009-03-28

The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') is the core coal combustion product (CCP) research group at the Energy & Environmental Research Center (EERC). CARRC focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of CCPs. CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCP utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program, which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCP performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 2007 to 2009 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCPs. The tasks were included in four categories: (1) Environmental Evaluations of CCPs; (2) Evaluation of Impacts on CCPs from Emission Controls; (3) Construction and Product-Related Activities; and (4) Technology Transfer and Maintenance Tasks. All tasks are designed to work toward achieving the CARRC overall goal and supporting objectives. The various tasks are coordinated in order to provide broad and useful technical data for CARRC members

Characterization of anti-liver-kidney microsome antibody (anti-LKM1) from hepatitis C virus-positive and -negative sera.

Science.gov (United States)

Yamamoto, A M; Cresteil, D; Homberg, J C; Alvarez, F

1993-06-01

Hepatitis C virus-related antibodies were found in sera positive for antibodies to liver/kidney microsome antibody, usually considered a marker of autoimmune hepatitis. The aim of this study was to analyze the specificity of this autoantibody in sera from patients with and without hepatitis C virus infection. Fifteen anti-hepatitis C virus- and anti-liver kidney microsome-positive sera were compared with 11 sera from patients with autoimmune hepatitis, for reactivity against rat and human liver microsomal proteins, P450IID6 recombinant proteins, and various synthetic peptides spanning the 241-429 amino acids sequence of the P450IID6. Ten of 11 sera from patients with autoimmune hepatitis bound to recombinant proteins spanning the P450IID6 region between amino acids 72 and 458. These sera bound to the 254-271 peptide, and some also recognized the 321-351, 373-389 and 410-429 peptides. Four of 15 antihepatitis C virus recognized the fusion protein coded by the full-length P450IID6 complementary DNA; 3 of them also reacted with the P450IID6 region between amino acids 72-456. Only 1 sera recognized the 321-351 peptide. P450IID6 antigenic sites recognized by anti-hepatitis C virus-positive sera were different from those recognized by sera from patients with autoimmune hepatitis.

Engineering development of selective agglomeration: Task 5, Bench- scale process testing

Energy Technology Data Exchange (ETDEWEB)

1991-09-01

Under the overall objectives of DOE Contract ``Engineering Development of Selective Agglomeration,`` there were a number of specific objectives in the Task 5 program. The prime objectives of Task 5 are highlighted below: (1) Maximize process performance in pyritic sulfur rejection and BTU recovery, (2) Produce a low ash product, (3) Compare the performance of the heavy agglomerant process based on diesel and the light agglomerant process using heptane, (4) Define optimum processing conditions for engineering design, (5) Provide first-level evaluation of product handleability, and (6) Explore and investigate process options/ideas which may enhance process performance and/or product handleability.

Effects of noise and task loading on a communication task loading on a communication task

Science.gov (United States)

Orrell, Dean H., II

Previous research had shown the effect of noise on a single communication task. This research has been criticized as not being representative of a real world situation since subjects allocated all of their attention to only one task. In the present study, the effect of adding a loading task to a standard noise-communication paradigm was investigated. Subjects performed both a communication task (Modified Rhyme Test; House et al. 1965) and a short term memory task (Sternberg, 1969) in simulated levels of aircraft noise (95, 105 and 115 dB overall sound pressure level (OASPL)). Task loading was varied with Sternberg's task by requiring subjects to memorize one, four, or six alphanumeric characters. Simulated aircraft noise was varied between levels of 95, 105 and 115 dB OASPL using a pink noise source. Results show that the addition of Sternberg's task and little effect on the intelligibility of the communication task while response time for the communication task increased.

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

Science.gov (United States)

Sanbonmatsu, David M; Strayer, David L; Medeiros-Ward, Nathan; Watson, Jason M

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

Directory of Open Access Journals (Sweden)

David M Sanbonmatsu

Full Text Available The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Who Multi-Tasks and Why? Multi-Tasking Ability, Perceived Multi-Tasking Ability, Impulsivity, and Sensation Seeking

Science.gov (United States)

Sanbonmatsu, David M.; Strayer, David L.; Medeiros-Ward, Nathan; Watson, Jason M.

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants’ perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation – high levels of impulsivity and sensation seeking – reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control - low scorers on the Operation Span task and persons high in impulsivity - tended to report higher levels of multi-tasking activity. PMID:23372720

Task demand, task management, and teamwork

Energy Technology Data Exchange (ETDEWEB)

Braarud, Per Oeivind; Brendryen, Haavar

2001-03-15

The current approach to mental workload assessment in process control was evaluated in 3 previous HAMMLAB studies, by analysing the relationship between workload related measures and performance. The results showed that subjective task complexity rating was related to team's control room performance, that mental effort (NASA-TLX) was weakly related to performance, and that overall activity level was unrelated to performance. The results support the argument that general cognitive measures, i.e., mental workload, are weakly related to performance in the process control domain. This implies that other workload concepts than general mental workload are needed for valid assessment of human reliability and for valid assessment of control room configurations. An assessment of task load in process control suggested that how effort is used to handle task demand is more important then the level of effort invested to solve the task. The report suggests two main workload related concepts with a potential as performance predictors in process control: task requirements, and the work style describing how effort is invested to solve the task. The task requirements are seen as composed of individual task demand and team demand. In a similar way work style are seen as composed of individual task management and teamwork style. A framework for the development of the concepts is suggested based on a literature review and experiences from HAMMLAB research. It is suggested that operational definitions of workload concepts should be based on observable control room behaviour, to assure a potential for developing performance-shaping factors. Finally an explorative analysis of teamwork measures and performance in one study indicated that teamwork concepts are related to performance. This lends support to the suggested development of team demand and teamwork style as elements of a framework for the analysis of workload in process control. (Author)

The task-to-task communication between computers

International Nuclear Information System (INIS)

Lin Shuzi; Zhang Bingyun; Zhao Weiren

1992-01-01

The task-to-task communication is used in the Institute of High Energy Physics. The BES (Beijing Spectrometer) uses the communication mode to take some of the BEPC (Beijing Electron Positron Collider) running parameters needed by BES experiments in a periodic time. The authors describe the principle of transparent task-to-task communication and how to use it in BES on-line data acquisition system

Study on Network Error Analysis and Locating based on Integrated Information Decision System

Science.gov (United States)

Yang, F.; Dong, Z. H.

2017-10-01

Integrated information decision system (IIDS) integrates multiple sub-system developed by many facilities, including almost hundred kinds of software, which provides with various services, such as email, short messages, drawing and sharing. Because the under-layer protocols are different, user standards are not unified, many errors are occurred during the stages of setup, configuration, and operation, which seriously affect the usage. Because the errors are various, which may be happened in different operation phases, stages, TCP/IP communication protocol layers, sub-system software, it is necessary to design a network error analysis and locating tool for IIDS to solve the above problems. This paper studies on network error analysis and locating based on IIDS, which provides strong theory and technology supports for the running and communicating of IIDS.

JV Task 6 - Coal Ash Resources Research Consortium Research

Energy Technology Data Exchange (ETDEWEB)

Debra Pflughoeft-Hassett; Tera Buckley; Bruce Dockter; Kurt Eylands; David Hassett; Loreal Heebink; Erick Zacher

2008-04-01

The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of coal combustion by-products (CCBs). CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCB utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program (JSRP), which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCB performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 1998 to 2007 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCBs. CARRC topical reports were prepared on several completed tasks. Specific CARRC 1998B2007 accomplishments included: (1) Development of several ASTM International Standard Guides for CCB utilization applications. (2) Organization and presentation of training courses for CCB professionals and teachers. (3) Development of online resources including the Coal Ash Resource Center, Ash from Biomass in Coal (ABC) of cocombustion ash characteristics, and the Buyer's Guide to Coal-Ash Containing Products. In addition

Computerized management of plant intervention tasks

International Nuclear Information System (INIS)

Quoidbach, G.

2004-01-01

The main objective of the 'Computerized Management of Plant Intervention Tasks' is to help the staff of a nuclear or a conventional power plant or of any other complex industrial facility (chemical industries, refineries, and so on) in planning, organizing, and carrying out any (preventive or corrective) maintenance task. This 'Computerized Management of Plant Intervention Tasks' is organized around a data base of all plant components in the facility that might be subjected to maintenance or tagout. It allows to manage, by means of intelligent and configurable 'mail service', the course of the intervention requests as well as various treatments of those requests, in a safe and efficient way, adapted to each particular organization. The concept of 'Computerized Management' of plant intervention tasks was developed by BELGATOM in 1983 for the Belgian nuclear power plants of ELECTRABEL. A first implementation of this concept was made at that time for the Doel NPP under the name POPIT (Programming Of Plant Intervention Tasks). In 1988, it was decided to proceed to a functional upgrade of the application, using advanced software and hardware techniques and products, and to realize a second implementation in the Tihange NPP under the name ACM (Application Consignation Maintenance). (author)

Task analysis and support for problem solving tasks

International Nuclear Information System (INIS)

Bainbridge, L.

1987-01-01

This paper is concerned with Task Analysis as the basis for ergonomic design to reduce human error rates, rather than for predicting human error rates. Task Analysis techniques usually provide a set of categories for describing sub tasks, and a framework describing the relations between sub-tasks. Both the task type categories and their organisation have implications for optimum interface and training design. In this paper, the framework needed for considering the most complex tasks faced by operators in process industries is discussed such as fault management in unexpected situations, and what is likely to minimise human error in these circumstances. (author)

Teaching Sustainable Process Design Using 12 Systematic Computer-Aided Tasks

DEFF Research Database (Denmark)

Babi, Deenesh K.

2015-01-01

(tasks 4-7) and then sizing, costing and economic analysis of the designed process (tasks 8-9). This produces a base case design. In tasks 10-12, the student explores opportunities for heat and/or mass integration, followed by a sustainability analysis, in order to evaluate the base case design and set......In this paper a task-based approach for teaching (sustainable) process design to students pursuing a degree in chemical and biochemical engineering is presented. In tasks 1-3 the student makes design decisions for product and process selection followed by simple and rigorous model simulations...... targets for further improvement. Finally, a process optimization problem is formulated and solved to obtain the more sustainable process design. The 12 tasks are explained in terms of input and output of each task and examples of application of this approach in an MSclevel course are reported....

Engineering development of selective agglomeration: Task 5, Bench- scale process testing

Energy Technology Data Exchange (ETDEWEB)

1991-09-01

Under the overall objectives of DOE Contract Engineering Development of Selective Agglomeration,'' there were a number of specific objectives in the Task 5 program. The prime objectives of Task 5 are highlighted below: (1) Maximize process performance in pyritic sulfur rejection and BTU recovery, (2) Produce a low ash product, (3) Compare the performance of the heavy agglomerant process based on diesel and the light agglomerant process using heptane, (4) Define optimum processing conditions for engineering design, (5) Provide first-level evaluation of product handleability, and (6) Explore and investigate process options/ideas which may enhance process performance and/or product handleability.

Generic cognitive adaptations to task interference in task switching

NARCIS (Netherlands)

Poljac, E.; Bekkering, H.

2009-01-01

The present study investigated how the activation of previous tasks interferes with the execution of future tasks as a result of temporal manipulations. Color and shape matching tasks were organized in runs of two trials each. The tasks were specified by a cue presented before a task run, cueing

Task-irrelevant auditory feedback facilitates motor performance in musicians

Directory of Open Access Journals (Sweden)

Virginia eConde

2012-05-01

Full Text Available An efficient and fast auditory–motor network is a basic resource for trained musicians due to the importance of motor anticipation of sound production in musical performance. When playing an instrument, motor performance always goes along with the production of sounds and the integration between both modalities plays an essential role in the course of musical training. The aim of the present study was to investigate the role of task-irrelevant auditory feedback during motor performance in musicians using a serial reaction time task (SRTT. Our hypothesis was that musicians, due to their extensive auditory–motor practice routine during musical training, have a superior performance and learning capabilities when receiving auditory feedback during SRTT relative to musicians performing the SRTT without any auditory feedback. Here we provide novel evidence that task-irrelevant auditory feedback is capable to reinforce SRTT performance but not learning, a finding that might provide further insight into auditory-motor integration in musicians on a behavioral level.

Working Memory Training Improves Dual-Task Performance on Motor Tasks.

Science.gov (United States)

Kimura, Takehide; Kaneko, Fuminari; Nagahata, Keita; Shibata, Eriko; Aoki, Nobuhiro

2017-01-01

The authors investigated whether working memory training improves motor-motor dual-task performance consisted of upper and lower limb tasks. The upper limb task was a simple reaction task and the lower limb task was an isometric knee extension task. 45 participants (age = 21.8 ± 1.6 years) were classified into a working memory training group (WM-TRG), dual-task training group, or control group. The training duration was 2 weeks (15 min, 4 times/week). Our results indicated that working memory capacity increased significantly only in the WM-TRG. Dual-task performance improved in the WM-TRG and dual-task training group. Our study provides the novel insight that working memory training improves dual-task performance without specific training on the target motor task.

NDSI products system based on Hadoop platform

Science.gov (United States)

Zhou, Yan; Jiang, He; Yang, Xiaoxia; Geng, Erhui

2015-12-01

Snow is solid state of water resources on earth, and plays an important role in human life. Satellite remote sensing is significant in snow extraction with the advantages of cyclical, macro, comprehensiveness, objectivity, timeliness. With the continuous development of remote sensing technology, remote sensing data access to the trend of multiple platforms, multiple sensors and multiple perspectives. At the same time, in view of the remote sensing data of compute-intensive applications demand increase gradually. However, current the producing system of remote sensing products is in a serial mode, and this kind of production system is used for professional remote sensing researchers mostly, and production systems achieving automatic or semi-automatic production are relatively less. Facing massive remote sensing data, the traditional serial mode producing system with its low efficiency has been difficult to meet the requirements of mass data timely and efficient processing. In order to effectively improve the production efficiency of NDSI products, meet the demand of large-scale remote sensing data processed timely and efficiently, this paper build NDSI products production system based on Hadoop platform, and the system mainly includes the remote sensing image management module, NDSI production module, and system service module. Main research contents and results including: (1)The remote sensing image management module: includes image import and image metadata management two parts. Import mass basis IRS images and NDSI product images (the system performing the production task output) into HDFS file system; At the same time, read the corresponding orbit ranks number, maximum/minimum longitude and latitude, product date, HDFS storage path, Hadoop task ID (NDSI products), and other metadata information, and then create thumbnails, and unique ID number for each record distribution, import it into base/product image metadata database. (2)NDSI production module: includes

Gestational Age Estimation Based on Fetal Pelvimetry on Fetal Ultrasound in Iraqi Women

Directory of Open Access Journals (Sweden)

Sattar Razzaq Al-Esawi

2016-08-01

Full Text Available Ultrasound is an integral part of obstetric practice, and assessment of gestational age (GA is a central element of obstetric ultrasonography. Sonographic estimation of GA is derived from calculations based on fetal measurements. Numerous equations for GA calculation from fetal biometry have been adopted in routine practice. This study reports a new method of estimating GA in the second and third trimester using interischial distance (IID, the distance between the two ischial primary ossification centers, on fetal ultrasound. Four hundred women with uncomplicated normal singleton pregnancies from 16 weeks to term were examined. Standard fetal obstetric ultrasound was done measuring biparietal diameter (BPD and femur length (FL for each fetus. The IID, in millimeters, was correlated with the GA in weeks based upon the BPD and FL individually, and the BPD and FL together. Statistical analysis showed strong correlation between the IID and GA calculated from the FL with correlation coefficient (r =0.989, P < 0.001. Strong linear correlation was also found between the IID and GA based upon BPD and BPD+FL. Further statistical analysis using regression equations also showed that the IID was slightly wider in female fetuses, but this difference was not statistically significant. Resulting from this analysis, we have arrived at an easy-to-use equation: GA Weeks = (IID mm + 8 ±1 week. We feel this method can be especially applicable in the developing world, where midwives may not have access to software for fetal biometry in their basic handheld ultrasound machines. Even more sophisticated machines may not come with loaded software for obstetrics analysis. There are several limitations to this study, discussed below. We recommend further studies correlating the IID with other biometric parameters.

Estimating the Incidence of Acute Infectious Intestinal Disease in the Community in the UK: A Retrospective Telephone Survey.

Directory of Open Access Journals (Sweden)

Laura Viviani

Full Text Available To estimate the burden of intestinal infectious disease (IID in the UK and determine whether disease burden estimations using a retrospective study design differ from those using a prospective study design.A retrospective telephone survey undertaken in each of the four countries comprising the United Kingdom. Participants were randomly asked about illness either in the past 7 or 28 days.14,813 individuals for all of whom we had a legible recording of their agreement to participate.Self-reported IID, defined as loose stools or clinically significant vomiting lasting less than two weeks, in the absence of a known non-infectious cause.The rate of self-reported IID varied substantially depending on whether asked for illness in the previous 7 or 28 days. After standardising for age and sex, and adjusting for the number of interviews completed each month and the relative size of each UK country, the estimated rate of IID in the 7-day recall group was 1,530 cases per 1,000 person-years (95% CI: 1135-2113, while in the 28-day recall group it was 533 cases per 1,000 person-years (95% CI: 377-778. There was no significant variation in rates between the four countries. Rates in this study were also higher than in a related prospective study undertaken at the same time.The estimated burden of disease from IID varied dramatically depending on study design. Retrospective studies of IID give higher estimates of disease burden than prospective studies. Of retrospective studies longer recall periods give lower estimated rates than studies with short recall periods. Caution needs to be exercised when comparing studies of self-reported IID as small changes in study design or case definition can markedly affect estimated rates.

True-and-error models violate independence and yet they are testable

Directory of Open Access Journals (Sweden)

Michael H. Birnbaum

2013-11-01

Full Text Available Birnbaum (2011 criticized tests of transitivity that are based entirely on binary choice proportions. When assumptions of independence and stationarity (iid of choice responses are violated, choice proportions could lead to wrong conclusions. Birnbaum (2012a proposed two statistics (correlation and variance of preference reversals to test iid, using random permutations to simulate p-values. Cha, Choi, Guo, Regenwetter, and Zwilling (2013 defended methods based on marginal proportions but conceded that such methods wrongly diagnose hypothetical examples of Birnbaum (2012a. However, they also claimed that ``true and error'' models also satisfy independence and also fail in such cases unless they become untestable. This article presents correct true-and-error models; it shows how these models violate iid, how they might correctly identify cases that would be misdiagnosed by marginal proportions, and how they can be tested and rejected. This note also refutes other arguments of Cha et al. (2013, including contentions that other tests failed to violate iid ``with flying colors'', that violations of iid ``do not replicate'', that type I errors are not appropriately estimated by the permutation method, and that independence assumptions are not critical to interpretation of marginal choice proportions.

Task 4.2.2: Task report prepared for the second CRP meeting 5-8 October 1993, Budapest, Hungary

International Nuclear Information System (INIS)

Fujita, Yushi

1993-01-01

This is a preliminary report on Task 4.2.2. of IAEA Coordinated Research Program on Operator Support Systems in Nuclear Power Plants. The purposes of Task 4.2.2 are defined as follows: evaluate functions assigned to operators, maintenance personnel, or plant management staff; identify where operator support systems (OSS) can support those functions in a productive way. In this report, discussion is made of (i) a framework for evaluating functions assigned to operators, maintenance personnel, or plant management staff, and (ii) where OSS can be most beneficial to support these functions. In addition, recommendations for future efforts are made

Task Switching in a Hierarchical Task Structure: Evidence for the Fragility of the Task Repetition Benefit

Science.gov (United States)

Lien, Mei-Ching; Ruthruff, Eric

2004-01-01

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms.…

Aplikasi Penjadwalan Tugas Berbasis Mobile Device Didukung Google Task Dan Google Drive

OpenAIRE

Anggraini, Elisa Yuni; Wibowo, Adi; Dewi, Lily Puspa

2017-01-01

As the increased of work productivity, many task scheduling applications are emerging. Each of Task scheduling applications has its own advantages to similar competitors. The applications helps the user to remember if one of task was approaching deadline, and to store activities' data. However, to fulfil the task, we need a container to store important files in a safe place. In recent years, the use of Cloud Computing is growing because the data is safely stored. In the applications mention...

Early Morphological Productivity in Hungarian: Evidence from Sentence Repetition and Elicited Production

Science.gov (United States)

Gabor, Balint; Lukacs, Agnes

2012-01-01

This paper investigates early productivity of morpheme use in Hungarian children aged between 2 ; 1 and 5 ; 3. Hungarian has a rich morphology which is the core marker of grammatical functions. A new method is introduced using the novel word paradigm in a sentence repetition task with masked inflections (i.e. a disguised elicited production task).…

Task-set inertia and memory-consolidation bottleneck in dual tasks.

Science.gov (United States)

Koch, Iring; Rumiati, Raffaella I

2006-11-01

Three dual-task experiments examined the influence of processing a briefly presented visual object for deferred verbal report on performance in an unrelated auditory-manual reaction time (RT) task. RT was increased at short stimulus-onset asynchronies (SOAs) relative to long SOAs, showing that memory consolidation processes can produce a functional processing bottleneck in dual-task performance. In addition, the experiments manipulated the spatial compatibility of the orientation of the visual object and the side of the speeded manual response. This cross-task compatibility produced relative RT benefits only when the instruction for the visual task emphasized overlap at the level of response codes across the task sets (Experiment 1). However, once the effective task set was in place, it continued to produce cross-task compatibility effects even in single-task situations ("ignore" trials in Experiment 2) and when instructions for the visual task did not explicitly require spatial coding of object orientation (Experiment 3). Taken together, the data suggest a considerable degree of task-set inertia in dual-task performance, which is also reinforced by finding costs of switching task sequences (e.g., AC --> BC vs. BC --> BC) in Experiment 3.

Experiments on laser driven beatwave acceleration in a ponderomotively formed plasma channel

International Nuclear Information System (INIS)

Tochitsky, S.Ya.; Narang, R.; Filip, C.V.; Clayton, C.E.; Marsh, K.A.; Joshi, C.; Musumeci, P.; Yoder, R.B.; Rosenzweig, J.B.; Pellegrini, C.

2004-01-01

A 10 ps long beam of 12 MeV electrons is externally injected into a ∼3-cm long plasma beatwave excited in a laser ionized hydrogen gas. The electrons have been accelerated to 50 MeV with a gradient of ∼1.3 GeV/m. It is shown that when the effective plasma wave amplitude-length product is limited by ionization-induced defocusing (IID), acceleration of electrons is significantly enhanced by using a laser pulse with a duration longer than the time required for ions to move across the laser spot size. Both experiments and two-dimensional simulations reveal that, in this case, self-guiding of the laser pulse in a ponderomotively formed plasma channel occurs. This compensates for IID and drives the beatwave over the longer length compared to when such a channel is not present

Wh-question intonation in Peninsular Spanish: Multiple contours and the effect of task type

Directory of Open Access Journals (Sweden)

Nicholas C. Henriksen

2009-06-01

Full Text Available This paper reports on an experimental investigation of wh-question intonation in Peninsular Spanish. Speech data were collected from six León, Spain Peninsular Spanish speakers, and oral production data were elicited under two conditions: a computerized sentence reading task and an information gap task-oriented dialogue. The latter task was an adaptation of the HCRC Map Task method (cf. Anderson et al., 1991 and was designed to elicit multiple wh-question productions in an unscripted and more spontaneous speech style than the standard sentence reading task. Results indicate that four contours exist in the tonal inventory of the six speakers. The two most frequent contours were a final rise contour and a nuclear circumflex contour. Systematic task-based differences were found for four of the six speakers, indicating that sentence reading task data alone may not accurately reflect spontaneous speech tonal patterns (cf. Cruttenden, 2007; but see also Lickley, Schepman, & Ladd, 2005. The experimental findings serve to clarify a number of assumptions about the syntax-prosody interface underlying wh-question utterance signaling; they also have implications for research methods in intonation and task-based variation in laboratory phonology.

Computational tasks in robotics and factory automation

NARCIS (Netherlands)

Biemans, Frank P.; Vissers, C.A.

1988-01-01

The design of Manufacturing Planning and Control Systems (MPCSs) — systems that negotiate with Customers and Suppliers to exchange products in return for money in order to generate profit, is discussed. The computational task of MPCS components are systematically specified as a starting point for

Who Multi-Tasks and Why? Multi-Tasking Ability, Perceived Multi-Tasking Ability, Impulsivity, and Sensation Seeking

OpenAIRE

Sanbonmatsu, David M.; Strayer, David L.; Medeiros-Ward, Nathan; Watson, Jason M.

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are ...

Environmentally Benign Stab Detonators

Energy Technology Data Exchange (ETDEWEB)

Gash, A E

2006-07-07

The coupling of energetic metallic multilayers (a.k.a. flash metal) with energetic sol-gel synthesis and processing is an entirely new approach to forming energetic devices for several DoD and DOE needs. They are also practical and commercially viable manufacturing techniques. Improved occupational safety and health, performance, reliability, reproducibility, and environmentally acceptable processing can be achieved using these methodologies and materials. The development and fielding of this technology will enhance mission readiness and reduce the costs, environmental risks and the necessity of resolving environmental concerns related to maintaining military readiness while simultaneously enhancing safety and health. Without sacrificing current performance, we will formulate new impact initiated device (IID) compositions to replace materials from the current composition that pose significant environmental, health, and safety problems associated with functions such as synthesis, material receipt, storage, handling, processing into the composition, reaction products from testing, and safe disposal. To do this, we will advance the use of nanocomposite preparation via the use of multilayer flash metal and sol-gel technologies and apply it to new small IIDs. This work will also serve to demonstrate that these technologies and resultant materials are relevant and practical to a variety of energetic needs of DoD and DOE. The goal will be to produce an IID whose composition is acceptable by OSHA, EPA, the Clean Air Act, Clean Water Act, Resource Recovery Act, etc. standards, without sacrificing current performance. The development of environmentally benign stab detonators and igniters will result in the removal of hazardous and toxic components associated with their manufacturing, handling, and use. This will lead to improved worker safety during manufacturing as well as reduced exposure of Service personnel during their storage and or use in operations. The

Co-integration Rank Testing under Conditional Heteroskedasticity

DEFF Research Database (Denmark)

Cavaliere, Guiseppe; Rahbæk, Anders; Taylor, A.M. Robert

null distributions of the rank statistics coincide with those derived by previous authors who assume either i.i.d. or (strict and covariance) stationary martingale difference innovations. We then propose wild bootstrap implementations of the co-integrating rank tests and demonstrate that the associated...... bootstrap rank statistics replicate the first-order asymptotic null distributions of the rank statistics. We show the same is also true of the corresponding rank tests based on the i.i.d. bootstrap of Swensen (2006). The wild bootstrap, however, has the important property that, unlike the i.i.d. bootstrap......, it preserves in the re-sampled data the pattern of heteroskedasticity present in the original shocks. Consistent with this, numerical evidence sug- gests that, relative to tests based on the asymptotic critical values or the i.i.d. bootstrap, the wild bootstrap rank tests perform very well in small samples un...

Influence of visual feedback on human task performance in ITER remote handling

Energy Technology Data Exchange (ETDEWEB)

Schropp, Gwendolijn Y.R., E-mail: g.schropp@heemskerk-innovative.nl [Utrecht University, Utrecht (Netherlands); Heemskerk Innovative Technology, Noordwijk (Netherlands); Heemskerk, Cock J.M. [Heemskerk Innovative Technology, Noordwijk (Netherlands); Kappers, Astrid M.L.; Tiest, Wouter M. Bergmann [Helmholtz Institute-Utrecht University, Utrecht (Netherlands); Elzendoorn, Ben S.Q. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM/FOM, Partner in the Trilateral Euregio Clusterand ITER-NL, PO box 1207, 3430 BE Nieuwegein (Netherlands); Bult, David [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM/FOM, Partner in the Trilateral Euregio Clusterand ITER-NL, PO box 1207, 3430 BE Nieuwegein (Netherlands)

2012-08-15

Highlights: Black-Right-Pointing-Pointer The performance of human operators in an ITER-like test facility for remote handling. Black-Right-Pointing-Pointer Different sources of visual feedback influence how fast one can complete a maintenance task. Black-Right-Pointing-Pointer Insights learned could be used in design of operator work environment or training procedures. - Abstract: In ITER, maintenance operations will be largely performed by remote handling (RH). Before ITER can be put into operation, safety regulations and licensing authorities require proof of maintainability for critical components. Part of the proof will come from using standard components and procedures. Additional verification and validation is based on simulation and hardware tests in 1:1 scale mockups. The Master Slave manipulator system (MS2) Benchmark Product was designed to implement a reference set of maintenance tasks representative for ITER remote handling. Experiments were performed with two versions of the Benchmark Product. In both experiments, the quality of visual feedback varied by exchanging direct view with indirect view (using video cameras) in order to measure and analyze its impact on human task performance. The first experiment showed that both experienced and novice RH operators perform a simple task significantly better with direct visual feedback than with camera feedback. A more complex task showed a large variation in results and could not be completed by many novice operators. Experienced operators commented on both the mechanical design and visual feedback. In a second experiment, a more elaborate task was tested on an improved Benchmark product. Again, the task was performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indicated that they regarded the lack of 3D perception as the primary factor hindering their performance.

Influence of visual feedback on human task performance in ITER remote handling

International Nuclear Information System (INIS)

Schropp, Gwendolijn Y.R.; Heemskerk, Cock J.M.; Kappers, Astrid M.L.; Tiest, Wouter M. Bergmann; Elzendoorn, Ben S.Q.; Bult, David

2012-01-01

Highlights: ► The performance of human operators in an ITER-like test facility for remote handling. ► Different sources of visual feedback influence how fast one can complete a maintenance task. ► Insights learned could be used in design of operator work environment or training procedures. - Abstract: In ITER, maintenance operations will be largely performed by remote handling (RH). Before ITER can be put into operation, safety regulations and licensing authorities require proof of maintainability for critical components. Part of the proof will come from using standard components and procedures. Additional verification and validation is based on simulation and hardware tests in 1:1 scale mockups. The Master Slave manipulator system (MS2) Benchmark Product was designed to implement a reference set of maintenance tasks representative for ITER remote handling. Experiments were performed with two versions of the Benchmark Product. In both experiments, the quality of visual feedback varied by exchanging direct view with indirect view (using video cameras) in order to measure and analyze its impact on human task performance. The first experiment showed that both experienced and novice RH operators perform a simple task significantly better with direct visual feedback than with camera feedback. A more complex task showed a large variation in results and could not be completed by many novice operators. Experienced operators commented on both the mechanical design and visual feedback. In a second experiment, a more elaborate task was tested on an improved Benchmark product. Again, the task was performed significantly faster with direct visual feedback than with camera feedback. In post-test interviews, operators indicated that they regarded the lack of 3D perception as the primary factor hindering their performance.

The Mobilization of Effort: Sergeants, Patrol Officers, and Productivity in an American Agency.

Science.gov (United States)

1982-02-01

the precinct captain complaining about the sergeant’s notorious "mandatory car stop" policies. After the sergeant’s words about "those fucking fools...internal investigations by 16 telling IID to "not go after my men" or to " fuck off" have a formidable ally and guardian. Of course, the price officers...sector covering a small, almost rural, lightly populated region where it was thought only the " fuck -ups were assigned -- an assignment from which it

Prevention of relapse of Graves' disease by treatment with an intrathyroid injection of dexamethasone.

Science.gov (United States)

Mao, Xiao-Ming; Li, Hui-Qin; Li, Qian; Li, Dong-Mei; Xie, Xiao-Jing; Yin, Guo-Ping; Zhang, Peng; Xu, Xiang-Hong; Wu, Jin-Dan; Chen, Song-Wang; Wang, Shu-Kui

2009-12-01

Antithyroid drugs are widely used in the treatment of Graves' disease (GD), but the relapse rate is very high after therapy withdrawal. We evaluated the reduction effects of intrathyroid injection of dexamethasone (IID) on the relapse rate of hyperthyroidism in patients with newly diagnosed GD. A total of 191 patients with GD completed the study. After 6 months of treatment with methimazole (MMI), the patients were randomly assigned to receive either MMI (96 patients) alone or MMI combined with IID (MMI+IID; 95 patients) treatment for 3 months, followed by continuing a dose of MMI that would maintain euthyroidism for the next 9 months in all of the patients. After withdrawal of the medical therapy, patients were followed for 24 months, and the relapse rate of hyperthyroidism was evaluated. No statistical difference was observed in the levels of serum FT(4), TSH, or TSH receptor antibodies (TR-Ab), the thyroid volume, or the TR-Ab positive rate between the two groups at month 6. After the next 3 months of treatment with MMI+IID or MMI alone, the levels of TSH increased significantly, and the levels of serum TR-Ab, the TR-Ab positive rate, and thyroid volume decreased significantly in the MMI+IID group compared with the MMI group. Seven patients (7.4%) experienced a relapse of overt hyperthyroidism in the MMI+IID group and 49 patients (51%) in MMI group during the 2-yr follow-up period (P prevent relapse of hyperthyroidism in GD after medical therapy withdrawal.

Genotypes and subtypes of Cryptosporidium spp. in diarrheic lambs and goat kids in northern Greece.

Science.gov (United States)

Papanikolopoulou, Vasiliki; Baroudi, Djamel; Guo, Yaqiong; Wang, Yuanfei; Papadopoulos, Elias; Lafi, Shwakat Q; Abd El-Tawab, Mohamed M; Diakou, Anastasia; Giadinis, Nektarios D; Feng, Yaoyu; Xiao, Lihua

2018-08-01

Inconsistent data exist on the distribution of zoonotic Cryptosporidium species and subtypes in sheep and goats in European countries, and few such data are available from Greece. In this study, 280 fecal specimens were collected from 132 diarrheic lambs and 148 diarrheic goat kids aged 4 to 15 days on 15 farms in northern Greece, and examined for Cryptosporidium spp. using microscopy of Ziehl-Neelsen-stained fecal smears. Cryptosporidium spp. in 80 microscopy-positive fecal specimens (39 from lambs and 41 from goat kids) were genotyped by PCR-RFLP analysis of the small subunit rRNA gene and subtyped by sequence analysis the 60 kDa glycoprotein gene. Among the 33 specimens successfully genotyped, C. parvum was found in 32 and C. xiaoi in one. Seven subtypes belonging to two subtype families (IIa and IId) were identified among the 29 C. parvum specimens successfully subtyped, including IIaA14G2R1 (1/29), IIaA15G2R1 (6/29), IIaA20G1R1 (7/29), IIdA14G2 (1/29), IIdA15G1 (9/29), IIdA16G1 (3/29), and IIdA23G1 (2/29). Lambs were more commonly infected with C. parvum IIa subtypes, whereas goat kids were more with IId subtypes. The results illustrate that C. parvum is prevalent in diarrheic lambs and goat kids in northern Greece and these animals could potentially play a role in epidemiology of human cryptosporidiosis. Copyright © 2018 Elsevier B.V. All rights reserved.

Development of an advanced continuous mild gasification process for the production of coproducts. Task 4, System integration studies: Char upgrading

Energy Technology Data Exchange (ETDEWEB)

Jha, M.C.; McCormick, R.L.; Hogsett, R.F.; Rowe, R.M.; Anast, K.R.

1991-12-01

This document describes the results of Task 4 under which a 50 pound/hour char-to-carbon (CTC) process research unit (PRU) was designed in the second half of 1989, with construction completed in June 1990. The CTC PRU at Golden was operated for nearly one year during which 35 runs were completed for a total of nearly 800 hours of operation. Char methanation and carbon production reactor development activities are detailed in this report, as well as the results of integrated runs of the CTC process. Evaluation of the process and the carbon product produced is also included. It was concluded that carbon could be produced from mild gasification char utilizing the CTC process. Char methanation and membrane separation steps performed reasonably well and can scaled up with confidence. However, the novel directly heated reactor system for methane cracking did not work satisfactorily due to materials of construction and heat transfer problems, which adversely affected the quantity and quality of the carbon product. Alternative reactor designs are recommended.

Dynamics of the central bottleneck: dual-task and task uncertainty.

Directory of Open Access Journals (Sweden)

Mariano Sigman

2006-07-01

Full Text Available Why is the human brain fundamentally limited when attempting to execute two tasks at the same time or in close succession? Two classical paradigms, psychological refractory period (PRP and task switching, have independently approached this issue, making significant advances in our understanding of the architecture of cognition. Yet, there is an apparent contradiction between the conclusions derived from these two paradigms. The PRP paradigm, on the one hand, suggests that the simultaneous execution of two tasks is limited solely by a passive structural bottleneck in which the tasks are executed on a first-come, first-served basis. The task-switching paradigm, on the other hand, argues that switching back and forth between task configurations must be actively controlled by a central executive system (the system controlling voluntary, planned, and flexible action. Here we have explicitly designed an experiment mixing the essential ingredients of both paradigms: task uncertainty and task simultaneity. In addition to a central bottleneck, we obtain evidence for active processes of task setting (planning of the appropriate sequence of actions and task disengaging (suppression of the plan set for the first task in order to proceed with the next one. Our results clarify the chronometric relations between these central components of dual-task processing, and in particular whether they operate serially or in parallel. On this basis, we propose a hierarchical model of cognitive architecture that provides a synthesis of task-switching and PRP paradigms.

Metabolic clearance and production rates of human growth hormone

Science.gov (United States)

Taylor, Andrew L.; Finster, Joseph L.; Mintz, Daniel H.

1969-01-01

The metabolic clearance rate (MCR) of human growth hormone (HGH) was determined by the constant infusion to equilibrium technique utilizing HGH-125I. 22 control subjects had a MCR of 229 ±52 ml/min (mean ±SD). No difference was evident between sexes, or between various age groups. Patients with acromegaly demonstrated normal MCR's. Moreover, acute elevations of plasma growth hormone concentrations in normal subjects did not alter the MCR of HGH. The MCR was relatively constant from day to day and within the day when subjects were evaluated in the supine position. In contrast, the assumption of the upright position was associated with a mean 24% decrease in the MCR. These results were contrasted with the MCR of HGH observed in a small number of patients with altered thyroid function or diabetes mellitus. In six patients with hypothyroidism the MCR (131 ±36 ml/min) was significantly decreased (P < 0.001); whereas the MCR in eight patients with hyperthyroidism (240 ±57 ml/min) did not differ from control subjects. The MCR in eight patients with insulin-independent diabetes mellitus (IID) (185 ±41 ml/min) and in eight patients with insulin-dependent diabetes mellitus (IDD) (136 ±31 ml/min) were significantly different from control subjects (P = < 0.05 and P = < 0.001, respectively). These data were interpreted to indicate that the plasma HGH-removing mechanism(s) is not saturated at physiologic plasma HGH levels, that plasma HGH levels alone may not permit distinction between variations in pituitary release of the hormone and its rate of clearance from the plasma, and that the estimation of the MCR of HGH may help clarify the mechanism of abnormal plasma HGH responses to various stimuli. Production rates of HGH (PR) in control subjects (347 ±173 mμg/min) were contrasted with hyperthyroid patients (529 ±242 mμg/min, P < 0.05), hypothyroid patients (160 ±69 mμg/min, P < 0.02), IID (245 ±100 mμg/min, NS), and IDD (363 ±153 mμg/min, NS). Considerable

Does the medium matter? The interaction of task type and technology on group performance and member reactions.

Science.gov (United States)

Straus, S G; McGrath, J E

1994-02-01

The authors investigated the hypothesis that as group tasks pose greater requirements for member interdependence, communication media that transmit more social context cues will foster group performance and satisfaction. Seventy-two 3-person groups of undergraduate students worked in either computer-mediated or face-to-face meetings on 3 tasks with increasing levels of interdependence: an idea-generation task, an intellective task, and a judgment task. Results showed few differences between computer-mediated and face-to-face groups in the quality of the work completed but large differences in productivity favoring face-to-face groups. Analysis of productivity and of members' reactions supported the predicted interaction of tasks and media, with greater discrepancies between media conditions for tasks requiring higher levels of coordination. Results are discussed in terms of the implications of using computer-mediated communications systems for group work.

Task analysis: a detailed example of stepping up from JSA

International Nuclear Information System (INIS)

Banks, W.W.; Paramore, B.A.; Buys, J.R.

1984-10-01

This paper discusses a pilot task analysis of operations in a proposed facility for the cutting and packaging of radioactively contaminated gloveboxes, for long-term storage or burial. The objective was to demonstrate how task analysis may be used as a tool for planning and risk management. Two specific products were generated - preliminary operating procedures and training requirements. The task data base, procedures list and training requirements developed were intended as first order categorizations. The analysis was limited to tasks that will be performed within the boundaries of the operational facility and the associated load-out area. The analysis documents tasks to be performed by D and D (Decontamination and Decommissioning) Workers. However, the analysis included all tasks identified as an integral part of glovebox processing within the facility. Thus tasks involving Radiation Protection Technicians (RPTs) are included. Based on hazard assessments, it is planned that at least two RPTs will be assigned full-time to the facility, so they may be considered part of its crew. Similarly, supervisory/administrative tasks are included where they were determined to be directly part of process sequences, such as obtaining appropriate certification. 11 tables

Monitoring supports performance in a dual-task paradigm involving a risky decision-making task and a working memory task

Directory of Open Access Journals (Sweden)

Bettina eGathmann

2015-02-01

Full Text Available Performing two cognitively demanding tasks at the same time is known to decrease performance. The current study investigates the underlying executive functions of a dual-tasking situation involving the simultaneous performance of decision making under explicit risk and a working memory task. It is suggested that making a decision and performing a working memory task at the same time should particularly require monitoring - an executive control process supervising behavior and the state of processing on two tasks. To test the role of a supervisory/monitoring function in such a dual-tasking situation we investigated 122 participants with the Game of Dice Task plus 2-back task (GDT plus 2-back task. This dual task requires participants to make decisions under risk and to perform a 2-back working memory task at the same time. Furthermore, a task measuring a set of several executive functions gathered in the term concept formation (Modified Card Sorting Test, MCST and the newly developed Balanced Switching Task (BST, measuring monitoring in particular, were used. The results demonstrate that concept formation and monitoring are involved in the simultaneous performance of decision making under risk and a working memory task. In particular, the mediation analysis revealed that BST performance partially mediates the influence of MCST performance on the GDT plus 2-back task. These findings suggest that monitoring is one important subfunction for superior performance in a dual-tasking situation including decision making under risk and a working memory task.

Monitoring supports performance in a dual-task paradigm involving a risky decision-making task and a working memory task

Science.gov (United States)

Gathmann, Bettina; Schiebener, Johannes; Wolf, Oliver T.; Brand, Matthias

2015-01-01

Performing two cognitively demanding tasks at the same time is known to decrease performance. The current study investigates the underlying executive functions of a dual-tasking situation involving the simultaneous performance of decision making under explicit risk and a working memory task. It is suggested that making a decision and performing a working memory task at the same time should particularly require monitoring—an executive control process supervising behavior and the state of processing on two tasks. To test the role of a supervisory/monitoring function in such a dual-tasking situation we investigated 122 participants with the Game of Dice Task plus 2-back task (GDT plus 2-back task). This dual task requires participants to make decisions under risk and to perform a 2-back working memory task at the same time. Furthermore, a task measuring a set of several executive functions gathered in the term concept formation (Modified Card Sorting Test, MCST) and the newly developed Balanced Switching Task (BST), measuring monitoring in particular, were used. The results demonstrate that concept formation and monitoring are involved in the simultaneous performance of decision making under risk and a working memory task. In particular, the mediation analysis revealed that BST performance partially mediates the influence of MCST performance on the GDT plus 2-back task. These findings suggest that monitoring is one important subfunction for superior performance in a dual-tasking situation including decision making under risk and a working memory task. PMID:25741308

Applying genetic algorithms for programming manufactoring cell tasks

Directory of Open Access Journals (Sweden)

Efredy Delgado

2005-05-01

Full Text Available This work was aimed for developing computational intelligence for scheduling a manufacturing cell's tasks, based manily on genetic algorithms. The manufacturing cell was modelled as beign a production-line; the makespan was calculated by using heuristics adapted from several libraries for genetic algorithms computed in C++ builder. Several problems dealing with small, medium and large list of jobs and machinery were resolved. The results were compared with other heuristics. The approach developed here would seem to be promising for future research concerning scheduling manufacturing cell tasks involving mixed batches.

The effects of stimulus modality and task integrality: Predicting dual-task performance and workload from single-task levels

Science.gov (United States)

Hart, S. G.; Shively, R. J.; Vidulich, M. A.; Miller, R. C.

1986-01-01

The influence of stimulus modality and task difficulty on workload and performance was investigated. The goal was to quantify the cost (in terms of response time and experienced workload) incurred when essentially serial task components shared common elements (e.g., the response to one initiated the other) which could be accomplished in parallel. The experimental tasks were based on the Fittsberg paradigm; the solution to a SternBERG-type memory task determines which of two identical FITTS targets are acquired. Previous research suggested that such functionally integrated dual tasks are performed with substantially less workload and faster response times than would be predicted by suming single-task components when both are presented in the same stimulus modality (visual). The physical integration of task elements was varied (although their functional relationship remained the same) to determine whether dual-task facilitation would persist if task components were presented in different sensory modalities. Again, it was found that the cost of performing the two-stage task was considerably less than the sum of component single-task levels when both were presented visually. Less facilitation was found when task elements were presented in different sensory modalities. These results suggest the importance of distinguishing between concurrent tasks that complete for limited resources from those that beneficially share common resources when selecting the stimulus modalities for information displays.

Resolving task rule incongruence during task switching by competitor rule suppression.

Science.gov (United States)

Meiran, Nachshon; Hsieh, Shulan; Dimov, Eduard

2010-07-01

Task switching requires maintaining readiness to execute any task of a given set of tasks. However, when tasks switch, the readiness to execute the now-irrelevant task generates interference, as seen in the task rule incongruence effect. Overcoming such interference requires fine-tuned inhibition that impairs task readiness only minimally. In an experiment involving 2 object classification tasks and 2 location classification tasks, the authors show that irrelevant task rules that generate response conflicts are inhibited. This competitor rule suppression (CRS) is seen in response slowing in subsequent trials, when the competing rules become relevant. CRS is shown to operate on specific rules without affecting similar rules. CRS and backward inhibition, which is another inhibitory phenomenon, produced additive effects on reaction time, suggesting their mutual independence. Implications for current formal theories of task switching as well as for conflict monitoring theories are discussed. (c) 2010 APA, all rights reserved

Developmental changes in using verbal self-cueing in task-switching situations: the impact of task practice and task-sequencing demands

Science.gov (United States)

Kray, Jutta; Gaspard, Hanna; Karbach, Julia; Blaye, Agnès

2013-01-01

In this study we examined whether developmental changes in using verbal self-cueing for task-goal maintenance are dependent on the amount of task practice and task-sequencing demands. To measure task-goal maintenance we applied a switching paradigm in which children either performed only task A or B in single-task blocks or switched between them on every second trial in mixed-task blocks. Task-goal maintenance was determined by comparing the performance between both blocks (mixing costs). The influence of verbal self-cueing was measured by instructing children to either name the next task aloud or not to verbalize during task preparation. Task-sequencing demands were varied between groups whereas one group received spatial task cues to support keeping track of the task sequence, while the other group did not. We also varied by the amount of prior practice in task switching while one group of participants practiced task switching first, before performing the task naming in addition, and the other group did it vice versa. Results of our study investigating younger (8–10 years) and older children (11–13 years) revealed no age differences in beneficial effects of verbal self-cueing. In line with previous findings, children showed reduced mixing costs under task-naming instructions and under conditions of low task-sequence demands (with the presence of spatial task cues). Our results also indicated that these benefits were only obtained for those groups of children that first received practice in task switching alone with no additional verbalization instruction. These findings suggest that internal task-cueing strategies can be efficiently used in children but only if they received prior practice in the underlying task so that demands on keeping and coordinating various instructions are reduced. Moreover, children benefitted from spatial task cues for better task-goal maintenance only if no verbal task-cueing strategy was introduced first. PMID:24381566

Behavioral Economic Purchase Tasks to Estimate Demand for Novel Nicotine/Tobacco Products and Prospectively Predict Future Use: Evidence from the Netherlands.

Science.gov (United States)

Heckman, Bryan W; Cummings, K Michael; Nahas, Georges J; Willemsen, Marc C; O'Connor, Richard J; Borland, Ron; Hirsch, Alexander A; Bickel, Warren K; Carpenter, Matthew J

2018-03-14

The demand for alternative nicotine/tobacco products is not well established. This paper uses a behavioral economic approach to test whether smokers have differential demand for conventional factory-made, electronic, and very low nicotine content cigarettes (FMCs/ECs/VLNCs) and uses the prospective cohort design to test the predictive validity of demand indices on subsequent use of commercially available FMCs and ECs. Daily smokers (>16 years) from the Netherlands completed an online survey in April 2014 (N=1215). Purchase tasks were completed for FMCs, ECs, and VLNCs. Participants indicated the number of cigarettes they would consume in 24 hours, across a range of prices (0-30 euro). The relationship between consumption and price was quantified into four indices of demand (intensity, Pmax, breakpoint, and essential value). A follow-up survey in July 2015 measured FMC and EC use. At baseline, greater demand was observed for FMCs relative to ECs and VLNCs across all demand indices, with no difference between ECs and VLNCs. At follow-up, greater baseline FMC demand (intensity, essential value) was associated with lower quit rates and higher relapse. EC demand (Pmax, breakpoint, essential value) was positively associated with any EC use between survey waves, past 30 day EC use, and EC purchase between waves. Smokers valued FMCs more than ECs or VLNCs, and FMCs were less sensitive to price increases. Demand indices predicted use of commercially available products over a 15 month period. To serve as viable substitutes for FMCs, ECs and VLNCs will need to be priced lower than FMCs. Purchase tasks can be adapted for novel nicotine/tobacco products as a means to efficiently quantify demand and predict use. Among current daily smokers, the demand for ECs and VLNCs is lower than FMCs.

Trading away what kind of jobs? Globalization, trade and tasks in the US economy.

Science.gov (United States)

Kemeny, Thomas; Rigby, David

2012-04-01

Economists and other social scientists are calling for a reassessment of the impact of international trade on labor markets in developed and developing countries. Classical models of globalization and trade, based upon the international exchange of finished goods, fail to capture the fragmentation of much commodity production and the geographical separation of individual production tasks. This fragmentation, captured in the growing volume of intra-industry trade, prompts investigation of the effects of trade within, rather than between, sectors of the economy. In this paper we examine the relationship between international trade and the task structure of US employment. We link disaggregate US trade data from 1972 to 2006, the NBER manufacturing database, the Decennial Census, and occupational and task data from the Dictionary of Occupational Titles. Within-industry shifts in task characteristics are linked to import competition and technological change. Our results suggest that trade has played a major role in the growth in relative demand for nonroutine tasks, particularly those requiring high levels of interpersonal interaction.

Age-related slowing of response selection and production in a visual choice reaction time task

Directory of Open Access Journals (Sweden)

David L Woods

2015-04-01

Full Text Available Aging is associated with delayed processing in choice reaction time (CRT tasks, but the processing stages most impacted by aging have not been clearly identified. Here, we analyzed CRT latencies in a computerized serial visual feature-conjunction task. Participants responded to a target letter (probability 40% by pressing one mouse button, and responded to distractor letters differing either in color, shape, or both features from the target (probabilities 20% each, by pressing the other mouse button. Stimuli were presented randomly to the left and right visual fields and stimulus onset asynchronies (SOAs were adaptively reduced following correct responses using a staircase procedure. In Experiment 1, we tested 1466 participants who ranged in age from 18 to 65 years. CRT latencies increased significantly with age (r = 0.47, 2.80 ms/year. Central processing time (CPT, isolated by subtracting simple reaction times (obtained in a companion experiment performed on the same day from CRT latencies, accounted for more than 80% of age-related CRT slowing, with most of the remaining increase in latency due to slowed motor responses. Participants were faster and more accurate when the stimulus location was spatially compatible with the mouse button used for responding, and this effect increased slightly with age. Participants took longer to respond to distractors with target color or shape than to distractors with no target features. However, the additional time needed to discriminate the more target-like distractors did not increase with age. In Experiment 2, we replicated the findings of Experiment 1 in a second population of 178 participants (ages 18-82 years. CRT latencies did not differ significantly in the two experiments, and similar effects of age, distractor similarity, and stimulus-response spatial compatibility were found. The results suggest that the age-related slowing in visual CRT latencies is largely due to delays in response selection and

Operational Readiness Review Plan for the Radioisotope Thermoelectric Generator Materials Production Tasks

Science.gov (United States)

Cooper, R. H.; Martin, M. M.; Riggs, C. R.; Beatty, R. L.; Ohriner, E. K.; Escher, R. N.

1990-04-19

In October 1989, a US shuttle lifted off from Cape Kennedy carrying the spacecraft Galileo on its mission to Jupiter. In November 1990, a second spacecraft, Ulysses, will be launched from Cape Kennedy with a mission to study the polar regions of the sun. The prime source of power for both spacecraft is a series of radioisotope thermoelectric generators (RTGs), which use plutonium oxide (plutonia) as a heat source. Several of the key components in this power system are required to ensure the safety of both the public and the environment and were manufactured at Oak Ridge National Laboratory (ORNL) in the 1980 to 1983 period. For these two missions, Martin Marietta Energy Systems, Inc. (Energy Systems), will provide an iridium alloy component used to contain the plutonia heat source and a carbon composite material that serves as a thermal insulator. ORNL alone will continue to fabricate the carbon composite material. Because of the importance to DOE that Energy Systems deliver these high quality components on time, performance of an Operational Readiness Review (ORR) of these manufacturing activities is necessary. Energy Systems Policy GP 24 entitled "Operational Readiness Process" describes the formal and comprehensive process by which appropriate Energy Systems activities are to be reviewed to ensure their readiness. This Energy System policy is aimed at reducing the risks associated with mission success and requires a management approved "readiness plan" to be issued. This document is the readiness plan for the RTG materials production tasks.

Influence of in-plane field on vertical Bloch line in the walls of the second kind of dumbbell domains at various temperatures

International Nuclear Information System (INIS)

Xu, J.P.; Liu, S.P.; Guo, G.X.; Zhen, C.M.; Tang, G.D.; Sun, H.Y.; Nie, X.F.

2004-01-01

The stability of vertical Bloch lines (VBLs) in the second kind of dumbbell domain (IIDs) walls in liquid phase epitaxy garnet bubble films subjected to an in-plane field at various temperatures is studied experimentally. It is found that there exists a critical in-plane field range depending on temperature, in which vertical Bloch lines (VBLs) in the second kind of IIDs walls are unstable, i.e., [Hip(1)(T),Hip(2)(T)]. Here, Hip(1)(T) is the initial critical in-plane field at which VBLs in the walls of IIDs annihilate; while Hip(2)(T) is the lowest in-plane field at which all VBLs in the walls of IIDs have annihilated completely. Also, the critical in-plane field range [Hip(1)(T),Hip(2)(T)],Hip(1)(T) and Hip(2)(T) all decrease with the temperature increasing. Hip(1)(T) and Hip(2)(T) reach zero at T0' and T0, respectively

Production management (1976)

International Nuclear Information System (INIS)

Lee, Sun Ryong

1976-03-01

This book introduces production management theory, which gives descriptions of production and system, systems approach, development of production management, Taylor system, Ford system, types of production system, measuring ingredients model of production management, decision of production management, selection of production facilities, arrangement of facilities design of work method and task, work measure system, demanding fore casting, production quality system and credibility system.

Task demands and individual variation in referring expressions

NARCIS (Netherlands)

Baltaretu, Adriana-Alexandra; Castro Ferreira, Thiago

Aiming to improve the human-likeness of natural language generation systems, this study investigates different sources of variation that might influence the production of referring expressions (REs), namely the effect of task demands and inter- intra- individual variation. We collected REs using a

The influence of principal managerial task performance on ...

African Journals Online (AJOL)

Poor performance of managerial tasks culminates declining staff productivity and thus deteriorating students academic performance. Secondary school students performance in most public examinations are not satisfactory in most states in Nigeria. Hence, this study investigate the extent to which secondary school principal ...

Contaminated sediment research task: SHC Task 3.61.3

Science.gov (United States)

A poster presentation for the SHC BOSC review will summarize the research efforts under Sustainable and Healthy Communities Research Program (SHC) in the Contaminated Sediment Task within the Contaminated Sites Project. For the Task, Problem Summary & Decision Context; Task O...

Learning Bounds of ERM Principle for Sequences of Time-Dependent Samples

Directory of Open Access Journals (Sweden)

Mingchen Yao

2015-01-01

Full Text Available Many generalization results in learning theory are established under the assumption that samples are independent and identically distributed (i.i.d.. However, numerous learning tasks in practical applications involve the time-dependent data. In this paper, we propose a theoretical framework to analyze the generalization performance of the empirical risk minimization (ERM principle for sequences of time-dependent samples (TDS. In particular, we first present the generalization bound of ERM principle for TDS. By introducing some auxiliary quantities, we also give a further analysis of the generalization properties and the asymptotical behaviors of ERM principle for TDS.

User productivity as a function of AutoCAD interface design.

Science.gov (United States)

Mitta, D A; Flores, P L

1995-12-01

Increased operator productivity is a desired outcome of user-CAD interaction scenarios. Two objectives of this research were to (1) define a measure of operator productivity and (2) empirically investigate the potential effects of CAD interface design on operator productivity, where productivity is defined as the percentage of a drawing session correctly completed per unit time. Here, AutoCAD provides the CAD environment of interest. Productivity with respect to two AutoCAD interface designs (menu, template) and three task types (draw, dimension, display) was investigated. Analysis of user productivity data revealed significantly higher productivity under the menu interface condition than under the template interface condition. A significant effect of task type was also discovered, where user productivity under display tasks was higher than productivity under the draw and dimension tasks. Implications of these results are presented.

Lexical Complexity of Decision-Making Writing Tasks: Form-focused Guided Strategic Planning

Directory of Open Access Journals (Sweden)

Fatemeh Mahdavirad

2016-06-01

Full Text Available The present study is an attempt to investigate the effect of form-focused guided strategic planning on lexical complexity of learners’ performance in writing tasks. The twenty intermediate level participants of the study performed an unplanned and then a planned decision-making task. In the planned task condition, the participants were provided with form-focused guided strategic planning which contained detailed instructions about how to plan, by being instructed to focus on form. The guidance included an explanation of the necessary structural and lexical patterns employed to express the learners’ views while developing a comparison-and-contrast paragraph in each task. The results of the statistical analysis indicated that the participants produced a written product with a greater lexical complexity in their performance of the task in the form-focused strategic planning condition. The findings emphasize the importance of guided strategic planning as a task condition in syllabus design for task-based language teaching and the necessity of incorporating this task feature for accomplishing lexical complexity in decision-making writing tasks.

Do tasks make a difference? Accounting for heterogeneity of performance of children with reading difficulties on tasks of executive function: findings from a meta-analysis.

Science.gov (United States)

Booth, Josephine N; Boyle, James M E; Kelly, Steve W

2010-03-01

Research studies have implicated executive functions in reading difficulties (RD). But while some studies have found children with RD to be impaired on tasks of executive function other studies report unimpaired performance. A meta-analysis was carried out to determine whether these discrepant findings can be accounted for by differences in the tasks of executive function that are utilized. A total of 48 studies comparing the performance on tasks of executive function of children with RD with their typically developing peers were included in the meta-analysis, yielding 180 effect sizes. An overall effect size of 0.57 (SE .03) was obtained, indicating that children with RD have impairments on tasks of executive function. However, effect sizes varied considerably suggesting that the impairment is not uniform. Moderator analysis revealed that task modality and IQ-achievement discrepancy definitions of RD influenced the magnitude of effect; however, the age and gender of participants and the nature of the RD did not have an influence. While the children's RD were associated with executive function impairments, variation in effect size is a product of the assessment task employed, underlying task demands, and definitional criteria.

Greenhouse gas balances of bioenergy systems: Programme and accomplishments of IEA Bioenergy Task XV, 1995-97

International Nuclear Information System (INIS)

Spitzer, J.

1998-01-01

The goal of IEA Bioenergy Task XV was to investigate all processes involved in using bioenergy systems, on a full fuel-cycle basis, with the aim of establishing overall greenhouse gas (GHG) balances. Task participants have been Austria, Canada, Finland, Sweden and the U.S.A. (Operating Agent: Austria). During its work period (1995-97), Task XV hosted five international workshops. The scientific achievements of the Task are documented in a number of published papers. Also, a bibliography on the research area was compiled. Much work was devoted to the question of carbon accounting in the context of the work of the Intergovernmental Panel on Climate Change (IPCC), and Task XV made contributions to a draft IPCC special report prepared for the IPCC Expert Group on Harvested Wood Products. The technical paper 'Forest harvests and wood products: sources and sinks of atmospheric carbon dioxide' (Forest Science, forthcoming) contrasts two carbon accounting approaches for considering wood products in the IPCC Guidelines (i.e., 'atmospheric-flow' vs. 'stock-change' method) and reports on estimated national carbon source-sink balances for selected countries, regions, and the world. Finally, progress was made in establishing a common analytical framework to compare different bioenergy options. The framework considers on-site carbon storage changes as well as GHG emissions from auxiliary fossil fuels, conversion efficiencies, and emission credits for by-products; comparisons between bioenergy systems and traditional fossil fuel and other energy systems as a reference are allowed, and reference land-uses accounted for. The continuation Task is Task 25 (1998-2000), with New Zealand joining the current partners 9 refs, 2 tabs

Cognitive pitfall! Videogame players are not immune to dual-task costs.

Science.gov (United States)

Donohue, Sarah E; James, Brittany; Eslick, Andrea N; Mitroff, Stephen R

2012-07-01

With modern technological advances, we often find ourselves dividing our attention between multiple tasks. While this may seem a productive way to live, our attentional capacity is limited, and this yields costs in one or more of the many tasks that we try to do. Some people believe that they are immune to the costs of multitasking and commonly engage in potentially dangerous behavior, such as driving while talking on the phone. But are some groups of individuals indeed immune to dual-task costs? This study examines whether avid action videogame players, who have been shown to have heightened attentional capacities, are particularly adept multitaskers. Participants completed three visually demanding experimental paradigms (a driving videogame, a multiple-object-tracking task, and a visual search), with and without answering unrelated questions via a speakerphone (i.e., with and without a dual-task component). All of the participants, videogame players and nonvideogame players alike, performed worse while engaging in the additional dual task for all three paradigms. This suggests that extensive videogame experience may not offer immunity from dual-task costs.

Influence of Productivity on the Acquisition of Inflectional Markers

DEFF Research Database (Denmark)

Kjærbæk, Laila; Basbøll, Hans; Christensen, René dePont

-Productive to Fully Productive PL markers. Empirical data Task 1: semi-naturalistic picture based elicitation task formed as semi-structured interviews. Participants: 80 monolingual Danish-speaking children between 3-9 years. Task 2: picture based elicitation task. The test material consists of 48 stimulus items....... Participants: 160 monolingual Danish-speaking children between 3-10 years. Results and conclusion The study shows that PL acquisition is affected by morphophonological category: children produce more correct PL forms of nouns with a Fully Productive PL marker than of nouns with a Semi...

Perception and action de-coupling in congenital amusia: sensitivity to task demands.

Science.gov (United States)

Williamson, Victoria J; Liu, Fang; Peryer, Guy; Grierson, Mick; Stewart, Lauren

2012-01-01

Theories that purport the existence of a distinct auditory action stream have received support from the finding that individuals with congenital amusia, a disorder of pitch perception, are able to reproduce the direction of a pitch change that they are unable to identify (Loui, Guenther, Mathys, & Schlaug, 2008). Although this finding has proved influential in theorizing about the existence of an auditory action-stream, aspects of the original study warrant further investigation. The present report attempts to replicate the original study's findings across a sizeable cohort of individuals with amusia (n=14), obtaining action (production) and perception thresholds for pitch direction. In contrast to the original study, we find evidence of a double dissociation: while a minority of amusics had lower (better) thresholds for production compared to perception of pitch, more than half showed the reverse pattern. To explore the impact of task demands, perception thresholds were also measured using a two alternative, criterion-free, forced choice task that avoided labeling demands. Controls' thresholds were task-invariant while amusics' thresholds were significantly task-dependent. We argue that the direction and extent of a perception/production dissociation in this population reflects individual differences in the mapping of pitch representations to labels ("up"; "down") and to the vocal apparatus, as opposed to anything intrinsically yoked to perception or action per se. Copyright © 2011 Elsevier Ltd. All rights reserved.

Strategic and Unpressured Within-Task Planning and Their Associations with Working Memory

Science.gov (United States)

Li, Shaofeng; Fu, Mengxia

2018-01-01

This study investigated the comparative effects of strategic and unpressured within-task planning on second language (L2) Chinese oral production and the role of working memory in mediating the effects of the two types of planning. Twenty-nine L2 Chinese learners at a large New Zealand university performed a narrative task after watching a…

Infectious Intestinal Diseases and Residential Water Services in Mexico: a Spatial Analysis

Directory of Open Access Journals (Sweden)

Nicholas P. Sisto

2017-09-01

Full Text Available Infectious intestinal diseases (IID represent a widespread public health problem in Mexico. The country also faces major challenges with respect to the provision of residential water services (piped water and sewer—an essential input for hygiene and cleanliness in homes. This paper analyzes morbidity rates from several IID associated with unsanitary living conditions along with a series of residential water services indicators for Mexico’s 2,456 municipalities. With data obtained through a special request to the federal epidemiological authority as well as official census data for 2010, we find stark regional contrasts and identify interesting spatial structures for both IID morbidity and residential water services indicators. In particular, municipalities tend to present values similar to neighboring municipalities, forming clusters of relatively high-value (or low-value municipalities. Moreover we find that municipalities with a relatively high level of access to residential water services tend to present relatively low IID morbidity rates. These results have multiple public policy implications. In order to reduce the incidence of IID effectively and efficiently, interventions should explicitly consider the spatial structure of morbidity and target problem spots—which typically spill over state, municipal and other administrative boundaries. Moreover, improvements in the quality of access to piped water (for example, increasing the frequency of supply may be as important for reducing morbidity as the expansion of basic access to this service.

Cognitive task analysis

NARCIS (Netherlands)

Schraagen, J.M.C.

2000-01-01

Cognitive task analysis is defined as the extension of traditional task analysis techniques to yield information about the knowledge, thought processes and goal structures that underlie observable task performance. Cognitive task analyses are conducted for a wide variety of purposes, including the

Comprehension and production of idioms in dysphasia.

Science.gov (United States)

Bush, P G; Drummond, S S

1985-10-01

The comprehension and production of idioms was investigated in 10 dysphasic adults. Two different tasks, one comprehension and the other production, were developed. The production task required the subject to verbally explain 15 idioms. The comprehension task necessitated the selection of the correct figurative representation of the idiom from four illustrations: a literal, a literal variation, a figurative, and an unrelated picture. Results indicated no significant correlation between overall comprehension and production performances. No significant difference was found between the comprehension or the production of idioms when type or severity of dysphasia was considered. A significant difference was found, however, in the type of incorrect response, in that subjects selected the literal depiction more often than other foil representations for the comprehension.

Children's Task Engagement during Challenging Puzzle Tasks

Science.gov (United States)

Wang, Feihong; Algina, James; Snyder, Patricia; Cox, Martha

2017-01-01

We examined children's task engagement during a challenging puzzle task in the presence of their primary caregivers by using a representative sample of rural children from six high-poverty counties across two states. Weighted longitudinal confirmatory factor analysis and structural equation modeling were used to identify a task engagement factor…

Application of robotic systems to nuclear power plant maintenance tasks

International Nuclear Information System (INIS)

Kok, K.D.; Bartilson, B.M.; Rosen, K.L.; Renner, G.F.; Law, T.M.

1984-01-01

Robotics technology has developed to where it can provide consistent performance of well-defined tasks. Although nuclear power plant maintenance tasks are characteristically unique, there are some common subtasks which have the consistency required for robots. Several maintenance activities were selected for further study. Concepts for robotic devices and rough scenarios for their use were developed and analyzed for their effect on maintenance costs. The results of the analysis, which was performed using a 10-year life and conservative estimates and procedures, indicate cost savings ranging from $100,000 to $1.5 M in net present value per robot. Projected purchase prices for the robots were less than $200,000. Although the robot concepts used commercially available technology, they are unlike any products either in use or widely required. Robot manufacturers are concentrating on mainstream applications in production, and are unlikely to develop such specialized products. The potential for cost savings indicates that developments should be funded by the nuclear industry

TTI Phase 2 Institutional Support: Indian Institute of Dalit Studies ...

International Development Research Centre (IDRC) Digital Library (Canada)

This funding will enhance the Indian Institute of Dalit Studies' (IIDS) role as a credible public policy institution in India by strengthening its ability to provide high-quality, influential, and policy-relevant research. About the Indian Institute of Dalit Studies IIDS is a social sciences research centre with a focus on development ...

RANDOM QUADRATIC-FORMS AND THE BOOTSTRAP FOR U-STATISTICS

NARCIS (Netherlands)

DEHLING, H; MIKOSCH, T

We study the bootstrap distribution for U-statistics with special emphasis on the degenerate case. For the Efron bootstrap we give a short proof of the consistency using Mallows' metrics. We also study the i.i.d. weighted bootstrap [GRAPHICS] where (X(i)) and (xi(i)) are two i.i.d. sequences,

Relating self reports of writing behaviour and online task execution using a temporal model

NARCIS (Netherlands)

Tillema, M.; van den Bergh, H.; Rijlaarsdam, G.; Sanders, T.

2011-01-01

Current theory about writing states that the quality of (meta)cognitive processing (i.e. planning, text production, revising, et cetera) is, at least partly, determined by the temporal distribution of (meta)cognitive activities across task execution. Put simply, the quality of task execution is

Toward a Model of Expert Knowledge Structure and Their Role in Cognitive Task Performance

Science.gov (United States)

1993-11-01

memory load. Grammars, specifically Task Action Grammar (TAG) (Payne and Green , 1986), and production rules (Newell and Simon, 1972) attempt to...Categorization, 259-303. Hillsdale, NJ: Earlbaum. Payne, S. J. and Green , T. R. G. (1986). Task-action grammars: a model of mental representation of task...PA 43235 lour,’Ar, IADr. Waich Creseas52242 Dr. Aliei Maimo Mail Sloe 23941 Behavoral Techaclopy NASA Are.s Anrirob Cenvnr Vcrr. M. Mile

Acute physical exercise affected processing efficiency in an auditory attention task more than processing effectiveness.

Science.gov (United States)

Dutke, Stephan; Jaitner, Thomas; Berse, Timo; Barenberg, Jonathan

2014-02-01

Research on effects of acute physical exercise on performance in a concurrent cognitive task has generated equivocal evidence. Processing efficiency theory predicts that concurrent physical exercise can increase resource requirements for sustaining cognitive performance even when the level of performance is unaffected. This hypothesis was tested in a dual-task experiment. Sixty young adults worked on a primary auditory attention task and a secondary interval production task while cycling on a bicycle ergometer. Physical load (cycling) and cognitive load of the primary task were manipulated. Neither physical nor cognitive load affected primary task performance, but both factors interacted on secondary task performance. Sustaining primary task performance under increased physical and/or cognitive load increased resource consumption as indicated by decreased secondary task performance. Results demonstrated that physical exercise effects on cognition might be underestimated when only single task performance is the focus.

Mapping of transport sensitive areas - Task 3.1

DEFF Research Database (Denmark)

Münier, Bernd

and retrieval of data available for pan European mapping exercises revealed a considerable number of high resolution maps suitable for production of map examples. The results have been documented as a spreadsheet, containing essential sets of metadata. Furthermore, it could be realised that the number...... and related sensitive areas in the EU deals with the operationalisation of the criteria for transport sensitivity and impacts, as defined in D2. This paper reports the findings of task 3.1, a Review on spatial approaches, mapping examples and available data sets at EU level. The outcomes of this task...... and quality of map data available is constantly increasing, both with regard to coverage of existing maps and the release of new maps or maps harmonised from national mapping tasks. Main data gaps seem to be within data on meteorology and air quality, as they only exist in rather coarse spatial resolution...

Two-Implant-Supported Mandibular Overdentures: Do Clinical Denture Quality and Inter-Implant Distance Affect Patient Satisfaction?

Science.gov (United States)

Alfadda, Sara A; Al Amri, Mohammad D; Al-Ohali, Amal; Al-Hakami, Arwa; Al-Madhi, Noura

To investigate the following three null hypotheses in patients rehabilitated with a mandibular overdenture supported by two unsplinted implants: (1) patient satisfaction is not related to the clinical quality of the dentures; (2) inter-implant distance (IID) has no effect on the clinical quality of the dentures; and (3) IID does not influence patient satisfaction. Forty edentulous patients who were rehabilitated with a two-implant-supported mandibular overdenture participated in the study. Independent investigators evaluated the dentures on the basis of five clinical criteria using the validated Denture Quality Evaluation Form, and the patients completed the validated Denture Satisfaction Scale. Irreversible hydrocolloid impressions of the mandible were made and poured immediately in die stone. The IID was measured by adapting an orthodontic wire to the mandibular alveolar ridge crest, extending from the center of one implant to the center of the other. Spearman correlation analyses were used to identify possible correlations, with a significance level set at P overdenture and of the maxillary conventional complete denture was significantly related to satisfaction (r = 0.389 and r = 0.44, respectively). Significant associations were found between the mandibular stability items and satisfaction with both maxillary and mandibular dentures. The stability of the maxillary denture was significantly associated with patient satisfaction with mandibular denture retention, stability, and comfort. None of the 12 denture satisfaction items were significantly associated with IID. Similarly, IID did not have an effect on the quality of either denture in terms of retention, stability, or occlusion. Denture stability was the feature that had the most influence on patient satisfaction with the mandibular overdenture and with the maxillary conventional denture. IID had no effect on the clinical quality of either denture and did not influence patient satisfaction.

A Hybrid Task Graph Scheduler for High Performance Image Processing Workflows.

Science.gov (United States)

Blattner, Timothy; Keyrouz, Walid; Bhattacharyya, Shuvra S; Halem, Milton; Brady, Mary

2017-12-01

Designing applications for scalability is key to improving their performance in hybrid and cluster computing. Scheduling code to utilize parallelism is difficult, particularly when dealing with data dependencies, memory management, data motion, and processor occupancy. The Hybrid Task Graph Scheduler (HTGS) improves programmer productivity when implementing hybrid workflows for multi-core and multi-GPU systems. The Hybrid Task Graph Scheduler (HTGS) is an abstract execution model, framework, and API that increases programmer productivity when implementing hybrid workflows for such systems. HTGS manages dependencies between tasks, represents CPU and GPU memories independently, overlaps computations with disk I/O and memory transfers, keeps multiple GPUs occupied, and uses all available compute resources. Through these abstractions, data motion and memory are explicit; this makes data locality decisions more accessible. To demonstrate the HTGS application program interface (API), we present implementations of two example algorithms: (1) a matrix multiplication that shows how easily task graphs can be used; and (2) a hybrid implementation of microscopy image stitching that reduces code size by ≈ 43% compared to a manually coded hybrid workflow implementation and showcases the minimal overhead of task graphs in HTGS. Both of the HTGS-based implementations show good performance. In image stitching the HTGS implementation achieves similar performance to the hybrid workflow implementation. Matrix multiplication with HTGS achieves 1.3× and 1.8× speedup over the multi-threaded OpenBLAS library for 16k × 16k and 32k × 32k size matrices, respectively.

Ornamental Horticulture Production Occupations. Curriculum Guide.

Science.gov (United States)

Reneau, Fred; And Others

This curriculum guide contains guidesheets for the ornamental horticulture production occupations. Each guidesheet provides a job-relevant task; performance objective, with task, performance standard, source of standard, and conditions for performance of task; enabling objectives; a list of resources; teaching activities; a criterion-referenced…

Expression, purification, crystallization and preliminary X-ray studies of the Ebola VP35 interferon inhibitory domain

International Nuclear Information System (INIS)

Leung, Daisy W.; Ginder, Nathaniel D.; Nix, Jay C.; Basler, Christopher F.; Honzatko, Richard B.; Amarasinghe, Gaya K.

2009-01-01

Native and selenomethionine-labeled crystals of Ebola VP35 interferon inhibitory domain were obtained by the hanging-drop vapor-diffusion method. Ebola VP35 is a multifunctional protein that is important for host immune suppression and pathogenesis. VP35 contains an N-terminal oligomerization domain and a C-terminal interferon inhibitory domain (IID). Mutations within the VP35 IID result in loss of host immune suppression. Here, efforts to crystallize recombinantly overexpressed VP35 IID that was purified from Escherichia coli are described. Native and selenomethionine-labeled crystals belonging to the orthorhombic space group P2 1 2 1 2 1 were obtained by the hanging-drop vapor-diffusion method and diffraction data were collected at the ALS synchrotron

Productivity standards for histology laboratories.

Science.gov (United States)

Buesa, René J

2010-04-01

The information from 221 US histology laboratories (histolabs) and 104 from 24 other countries with workloads from 600 to 116 000 cases per year was used to calculate productivity standards for 23 technical and 27 nontechnical tasks and for 4 types of work flow indicators. The sample includes 254 human, 40 forensic, and 31 veterinary pathology services. Statistical analyses demonstrate that most productivity standards are not different between services or worldwide. The total workload for the US human pathology histolabs averaged 26 061 cases per year, with 54% between 10 000 and less than 30 000. The total workload for 70% of the histolabs from other countries was less than 20 000, with an average of 15 226 cases per year. The fundamental manual technical tasks in the histolab and their productivity standards are as follows: grossing (14 cases per hour), cassetting (54 cassettes per hour), embedding (50 blocks per hour), and cutting (24 blocks per hour). All the other tasks, each with their own productivity standards, can be completed by auxiliary staff or using automatic instruments. Depending on the level of automation of the histolab, all the tasks derived from a workload of 25 cases will require 15.8 to 17.7 hours of work completed by 2.4 to 2.7 employees with 18% of their working time not directly dedicated to the production of diagnostic slides. This article explains how to extrapolate this productivity calculation for any workload and different levels of automation. The overall performance standard for all the tasks, including 8 hours for automated tissue processing, is 3.2 to 3.5 blocks per hour; and its best indicator is the value of the gross work flow productivity that is essentially dependent on how the work is organized. This article also includes productivity standards for forensic and veterinary histolabs, but the staffing benchmarks for histolabs will be the subject of a separate article. Copyright 2010 Elsevier Inc. All rights reserved.

Walking modality, but not task difficulty, influences the control of dual-task walking.

Science.gov (United States)

Wrightson, J G; Smeeton, N J

2017-10-01

During dual-task gait, changes in the stride-to-stride variability of stride time (STV) are suggested to represent the allocation of cognitive control to walking [1]. However, contrasting effects have been reported for overground and treadmill walking, which may be due to differences in the relative difficulty of the dual task. Here we compared the effect of overground and treadmill dual-task walking on STV in 18 healthy adults. Participants walked overground and on a treadmill for 120s during single-task (walking only) and dual-task (walking whilst performing serial subtractions in sevens) conditions. Dual-task effects on STV, cognitive task (serial subtraction) performance and perceived task difficulty were compared between walking modalities. STV was increased during overground dual-task walking, but was unchanged during treadmill dual-task walking. There were no differences in cognitive task performance or perceived task difficulty. These results show that gait is controlled differently during overground and treadmill dual-task walking. However, these differences are not solely due to differences in task difficulty, and may instead represent modality dependent control strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

Principles for designing mathematical tasks that enhance imitative and creative reasoning

OpenAIRE

Lithner, Johan

2017-01-01

The design research programme Learning by Imitative and Creative Reasoning (LICR) studies whether, how and why tasks and teaching that enhance creative reasoning lead to a more productive struggle and more efficient learning than the common but inefficient task designs based on imitating given solution procedures. The purpose of this paper is to synthesise the research outcomes determined to date by providing the following: a conceptual framework for key concepts and relationships among teach...

Task versus relationship conflict, team performance, and team member satisfaction: a meta-analysis.

Science.gov (United States)

De Dreu, Carsten K W; Weingart, Laurie R

2003-08-01

This study provides a meta-analysis of research on the associations between relationship conflict, task conflict, team performance, and team member satisfaction. Consistent with past theorizing, results revealed strong and negative correlations between relationship conflict, team performance, and team member satisfaction. In contrast to what has been suggested in both academic research and introductory textbooks, however, results also revealed strong and negative (instead of the predicted positive) correlations between task conflict team performance, and team member satisfaction. As predicted, conflict had stronger negative relations with team performance in highly complex (decision making, project, mixed) than in less complex (production) tasks. Finally, task conflict was less negatively related to team performance when task conflict and relationship conflict were weakly, rather than strongly, correlated.

78 FR 2996 - Meeting of the Community Preventive Services Task Force (Task Force)

Science.gov (United States)

2013-01-15

... Community Preventive Services Task Force (Task Force) AGENCY: Centers for Disease Control and Prevention... Services Task Force (Task Force). The Task Force is independent and nonfederal. Its members are nationally.... The Task Force was convened in 1996 by the Department of Health and Human Services (HHS) to assess the...

77 FR 56845 - Meeting of the Community Preventive Services Task Force (Task Force)

Science.gov (United States)

2012-09-14

... Community Preventive Services Task Force (Task Force) AGENCY: Centers for Disease Control and Prevention... Services Task Force (Task Force). The Task Force is independent and nonfederal. Its members are nationally.... The Task Force was convened in 1996 by the Department of Health and Human Services (HHS) to assess the...

78 FR 27969 - Meeting of the Community Preventive Services Task Force (Task Force)

Science.gov (United States)

2013-05-13

... Community Preventive Services Task Force (Task Force) AGENCY: Centers for Disease Control and Prevention... Services Task Force (Task Force). The Task Force is independent and nonfederal. Its members are nationally.... The Task Force was convened in 1996 by the Department of Health and Human Services (HHS) to assess the...

Beads task vs. box task: The specificity of the jumping to conclusions bias.

Science.gov (United States)

Balzan, Ryan P; Ephraums, Rachel; Delfabbro, Paul; Andreou, Christina

2017-09-01

Previous research involving the probabilistic reasoning 'beads task' has consistently demonstrated a jumping-to-conclusions (JTC) bias, where individuals with delusions make decisions based on limited evidence. However, recent studies have suggested that miscomprehension may be confounding the beads task. The current study aimed to test the conventional beads task against a conceptually simpler probabilistic reasoning "box task" METHODS: One hundred non-clinical participants completed both the beads task and the box task, and the Peters et al. Delusions Inventory (PDI) to assess for delusion-proneness. The number of 'draws to decision' was assessed for both tasks. Additionally, the total amount of on-screen evidence was manipulated for the box task, and two new box task measures were assessed (i.e., 'proportion of evidence requested' and 'deviation from optimal solution'). Despite being conceptually similar, the two tasks did not correlate, and participants requested significantly less information on the beads task relative to the box task. High-delusion-prone participants did not demonstrate hastier decisions on either task; in fact, for box task, this group was observed to be significantly more conservative than low-delusion-prone group. Neither task was incentivized; results need replication with a clinical sample. Participants, and particularly those identified as high-delusion-prone, displayed a more conservative style of responding on the novel box task, relative to the beads task. The two tasks, whilst conceptually similar, appear to be tapping different cognitive processes. The implications of these results are discussed in relation to the JTC bias and the theoretical mechanisms thought to underlie it. Copyright © 2016 Elsevier Ltd. All rights reserved.

EEG correlates of task engagement and mental workload in vigilance, learning, and memory tasks.

Science.gov (United States)

Berka, Chris; Levendowski, Daniel J; Lumicao, Michelle N; Yau, Alan; Davis, Gene; Zivkovic, Vladimir T; Olmstead, Richard E; Tremoulet, Patrice D; Craven, Patrick L

2007-05-01

The ability to continuously and unobtrusively monitor levels of task engagement and mental workload in an operational environment could be useful in identifying more accurate and efficient methods for humans to interact with technology. This information could also be used to optimize the design of safer, more efficient work environments that increase motivation and productivity. The present study explored the feasibility of monitoring electroencephalo-graphic (EEG) indices of engagement and workload acquired unobtrusively and quantified during performance of cognitive tests. EEG was acquired from 80 healthy participants with a wireless sensor headset (F3-F4,C3-C4,Cz-POz,F3-Cz,Fz-C3,Fz-POz) during tasks including: multi-level forward/backward-digit-span, grid-recall, trails, mental-addition, 20-min 3-Choice Vigilance, and image-learning and memory tests. EEG metrics for engagement and workload were calculated for each 1 -s of EEG. Across participants, engagement but not workload decreased over the 20-min vigilance test. Engagement and workload were significantly increased during the encoding period of verbal and image-learning and memory tests when compared with the recognition/ recall period. Workload but not engagement increased linearly as level of difficulty increased in forward and backward-digit-span, grid-recall, and mental-addition tests. EEG measures correlated with both subjective and objective performance metrics. These data in combination with previous studies suggest that EEG engagement reflects information-gathering, visual processing, and allocation of attention. EEG workload increases with increasing working memory load and during problem solving, integration of information, analytical reasoning, and may be more reflective of executive functions. Inspection of EEG on a second-by-second timescale revealed associations between workload and engagement levels when aligned with specific task events providing preliminary evidence that second

Structural and functional characterization of Reston Ebola virus VP35 interferon inhibitory domain.

Science.gov (United States)

Leung, Daisy W; Shabman, Reed S; Farahbakhsh, Mina; Prins, Kathleen C; Borek, Dominika M; Wang, Tianjiao; Mühlberger, Elke; Basler, Christopher F; Amarasinghe, Gaya K

2010-06-11

Ebolaviruses are causative agents of lethal hemorrhagic fever in humans and nonhuman primates. Among the filoviruses characterized thus far, Reston Ebola virus (REBOV) is the only Ebola virus that is nonpathogenic to humans despite the fact that REBOV can cause lethal disease in nonhuman primates. Previous studies also suggest that REBOV is less effective at inhibiting host innate immune responses than Zaire Ebola virus (ZEBOV) or Marburg virus. Virally encoded VP35 protein is critical for immune suppression, but an understanding of the relative contributions of VP35 proteins from REBOV and other filoviruses is currently lacking. In order to address this question, we characterized the REBOV VP35 interferon inhibitory domain (IID) using structural, biochemical, and virological studies. These studies reveal differences in double-stranded RNA binding and interferon inhibition between the two species. These observed differences are likely due to increased stability and loss of flexibility in REBOV VP35 IID, as demonstrated by thermal shift stability assays. Consistent with this finding, the 1.71-A crystal structure of REBOV VP35 IID reveals that it is highly similar to that of ZEBOV VP35 IID, with an overall backbone r.m.s.d. of 0.64 A, but contains an additional helical element at the linker between the two subdomains of VP35 IID. Mutations near the linker, including swapping sequences between REBOV and ZEBOV, reveal that the linker sequence has limited tolerance for variability. Together with the previously solved ligand-free and double-stranded-RNA-bound forms of ZEBOV VP35 IID structures, our current studies on REBOV VP35 IID reinforce the importance of VP35 in immune suppression. Functional differences observed between REBOV and ZEBOV VP35 proteins may contribute to observed differences in pathogenicity, but these are unlikely to be the major determinant. However, the high level of similarity in structure and the low tolerance for sequence variability, coupled

Automatic Retrieval of Newly Instructed Cue-Task Associations Seen in Task-Conflict Effects in the First Trial after Cue-Task Instructions.

Science.gov (United States)

Meiran, Nachshon; Pereg, Maayan

2017-01-01

Novel stimulus-response associations are retrieved automatically even without prior practice. Is this true for novel cue-task associations? The experiment involved miniblocks comprising three phases and task switching. In the INSTRUCTION phase, two new stimuli (or familiar cues) were arbitrarily assigned as cues for up-down/right-left tasks performed on placeholder locations. In the UNIVALENT phase, there was no task cue since placeholder's location afforded one task but the placeholders were the stimuli that we assigned as task cues for the following BIVALENT phase (involving target locations affording both tasks). Thus, participants held the novel cue-task associations in memory while executing the UNIVALENT phase. Results show poorer performance in the first univalent trial when the placeholder was associated with the opposite task (incompatible) than when it was compatible, an effect that was numerically larger with newly instructed cues than with familiar cues. These results indicate automatic retrieval of newly instructed cue-task associations.

Attentional Focusing Instructions and Force Production

Directory of Open Access Journals (Sweden)

David C Marchant

2011-01-01

Full Text Available Research progress assessing the role of attentional focusing instructions on skill acquisition and performance has lead researchers to apply this approach to force production tasks. Initial converging evidence indicates that force production tasks are sensitive to verbal instruction; externally focused instructions (onto movement outcomes, or onto the object force is being exerted against are shown to be more beneficial than internally focused instructions (focusing attention onto the movements being executed. These benefits are observed for maximal and accurate force production, as well as the maintenance of force production in prolonged tasks. A range of mechanisms are identified supporting the proposal that an external focus promotes movement efficiency in line with energy and effort conservation. Future research is required to assess how this developing body of work interacts with the broader understanding of psychological and physiological factors implicated in the effective production, maintenance and limitation of maximal or sub-maximal forces.

The BOLD Response during Stroop Task-Like Inhibition Paradigms: Effects of Task Difficulty and Task-Relevant Modality

Science.gov (United States)

Mitchell, Rachel L. C.

2005-01-01

Previous studies of the Stroop task propose two key mediators: the prefrontal and cingulate cortices but hints exist of functional specialization within these regions. This study aimed to examine the effect of task modality upon the prefrontal and cingulate response by examining the response to colour, number, and shape Stroop tasks whilst BOLD…

A PROSPECTIVE STUDY OF AIR WAY ASSESSMENT BY SIMPLE B ED SIDE TEST IN INDIAN PATIENTS

Directory of Open Access Journals (Sweden)

Patil

2015-06-01

Full Text Available Simple bedside tests for airway assessment were performed in 500 randomly selected Indian adult patients posted for surgery . The parameters studied were Thyromental distance ( TMD , Inter incisor distance ( IID Sternomental distance ( STMD , Ratio of height to thyromental distance ( RHTMD , Laryngeal mobility ( LM and Mallampati classification . The TMD , STMD , IID , RHTMD and LM measurements were consolidated into three groups namely normal , moderate and low scores . The airway parameters were finally co - related with the Mallampati classification . The normal range of values observed in Indian patients were TMD - 6 - 7cms , IID - 4 . 5 - 5 . 5 cms , STMD - 14 - 15cms , RHTMD - 18 - 22 and LM was good in 90% of patients assessed . The airway parameters of TMD , STMD , RHTMD , IID and LM in conjunction with Mallampati classification may be a useful routine preoperative screening te st for predicting intubation difficulties in Indian population . BACKGROUND AND AIMS : Difficult airway assessment is based on various anatomic parameters of upper airway , much of it being concentrated on oral cavity and the pharyngeal structures . The diagno stic value of tests based on neck anatomy in predicting difficult laryngoscopy was assessed in this prospective , open cohort study . METHODS : We studied 500 adult patients scheduled to receive general anaesthesia . Thyromental distance ( TMD , Sternomental Distance ( STMD , I nterincisior Distance ( IID , Ratio of Height t o Thyromental Distance ( RHTMD , Mallampatti Classification ( MPC , Laryngeal Mobility ( LM was calculated . The laryngoscopic view was classified according to the Cormack - Lehane Grade ( 1 - 4 . Di fficult laryngoscopy was defined as Cormack - Lehane Grade 3 or 4 . The optimal cut - off points for each variable were identified by using receiver operating characteristic analysis . Sensitivity , specificity and positive predictive value and negative predictiv e value ( NPV were

You can’t kid a kidder: Association between production and detection of deception in an interactive deception task

Directory of Open Access Journals (Sweden)

Gordon R.T. Wright

2012-04-01

Full Text Available Both the ability to deceive others, and the ability to detect deception, have long been proposed to confer an evolutionary advantage. Deception detection has been studied extensively, and the finding that typical individuals fare little better than chance in detecting deception is one of the more robust in the behavioral sciences. Surprisingly, little research has examined individual differences in lie-production ability. As a consequence, as far as we are aware, no previous study has investigated whether there exists an association between the ability to lie successfully and the ability to detect lies. Furthermore, only a minority of studies have examined deception as it naturally occurs; in a social, interactive setting. The present study therefore explored the relationship between these two facets of deceptive behavior by employing a novel competitive interactive deception task. For the first time, signal-detection theory was used to measure performance in both the detection and production of deception. A significant relationship was found between the deception-related abilities; those who could accurately detect a lie were able to produce statements that others found difficult to classify as deceptive or truthful. Furthermore, neither ability was related to measures of intelligence or emotional ability. We therefore suggest the existence of an underlying deception-general ability that varies across individuals.

Spatio-Temporal Evolution of Sporulation in Bacillus thuringiensis Biofilm.

Science.gov (United States)

El-Khoury, Nay; Majed, Racha; Perchat, Stéphane; Kallassy, Mireille; Lereclus, Didier; Gohar, Michel

2016-01-01

Bacillus thuringiensis can produce a floating biofilm which includes two parts: a ring and a pellicle. The ring is a thick structure which sticks to the culture container, while the pellicle extends over the whole liquid surface and joins the ring. We have followed over time, from 16 to 96 h, sporulation in the two biofilm parts. Sporulation was followed in situ in 48-wells polystyrene microtiterplates with a fluorescence binocular stereomicroscope and a spoIID-yfp transcriptional fusion. Sporulation took place much earlier in the ring than in the pellicle. In 20 h-aged biofilms, spoIID was expressed only in the ring, which could be seen as a green fluorescent circle surrounding the non-fluorescent pellicle. However, after 48 h of culture, the pellicle started to express spoIID in specific area corresponding to protrusions, and after 96 h both the ring and the whole pellicle expressed spoIID. Spore counts and microscopy observations of the ring and the pellicle harvested separately confirmed these results and revealed that sporulation occured 24 h-later in the pellicle comparatively to the ring, although both structures contained nearly 100% spores after 96 h of culture. We hypothesize that two mechanisms, due to microenvironments in the biofilm, can explain this difference. First, the ring experiences a decreased concentration of nutrients earlier than the pellicle, because of a lower exchange area with the culture medium. An second, the ring is exposed to partial dryness. Both reasons could speed up sporulation in this biofilm structure. Our results also suggest that spores in the biofilm display a phenotypic heterogeneity. These observations might be of particular significance for the food industry, since the biofilm part sticking to container walls - the ring - is likely to contain spores and will therefore resist both to washing and to cleaning procedures, and will be able to restart a new biofilm when food production has resumed.

Investigating Antecedents of Task Commitment and Task Attraction in Service Learning Team Projects

Science.gov (United States)

Schaffer, Bryan S.; Manegold, Jennifer G.

2018-01-01

The authors investigated the antecedents of team task cohesiveness in service learning classroom environments. Focusing on task commitment and task attraction as key dependent variables representing cohesiveness, and task interdependence as the primary independent variable, the authors position three important task action phase processes as…

78 FR 59939 - Meeting of the Community Preventive Services Task Force (Task Force)

Science.gov (United States)

2013-09-30

... Community Preventive Services Task Force (Task Force) AGENCY: Centers for Disease Control and Prevention... September 17, 2013, announcing the next meeting of the Community Preventive Services Task Force (Task Force... the Task Force to consider the findings of systematic reviews and issue findings and recommendations...

Task-related fMRI in hemiplegic cerebral palsy-A systematic review.

Science.gov (United States)

Gaberova, Katerina; Pacheva, Iliyana; Ivanov, Ivan

2018-04-27

Functional magnetic resonance imaging (fMRI) is used widely to study reorganization after early brain injuries. Unilateral cerebral palsy (UCP) is an appealing model for studying brain plasticity by fMRI. To summarize the results of task-related fMRI studies in UCP in order to get better understanding of the mechanism of neuroplasticity of the developing brain and its reorganization potential and better translation of this knowledge to clinical practice. A systematic search was conducted on the PubMed database by keywords: "cerebral palsy", "congenital hemiparesis", "unilateral", "Magnetic resonance imaging" , "fMRI", "reorganization", and "plasticity" The exclusion criteria were as follows: case reports; reviews; studies exploring non-UCP patients; and studies with results of rehabilitation. We found 7 articles investigated sensory tasks; 9 studies-motor tasks; 12 studies-speech tasks. Ipsilesional reorganization is dominant in sensory tasks (in 74/77 patients), contralesional-in only 3/77. In motor tasks, bilateral activation is found in 64/83, only contralesional-in 11/83, and only ipsilesional-8/83. Speech perception is bilateral in 35/51, only or dominantly ipsilesional (left-sided) in 8/51, and dominantly contralesional (right-sided) in 8/51. Speech production is only or dominantly contralesional (right-sided) in 88/130, bilateral-26/130, and only or dominantly ipsilesional (left-sided)-in 16/130. The sensory system is the most "rigid" to reorganization probably due to absence of ipsilateral (contralesional) primary somatosensory representation. The motor system is more "flexible" due to ipsilateral (contralesional) motor pathways. The speech perception and production show greater flexibility resulting in more bilateral or contralateral activation. The models of reorganization are variable, depending on the development and function of each neural system and the extent and timing of the damage. The plasticity patterns may guide therapeutic intervention and

Global product development

DEFF Research Database (Denmark)

Taylor, Thomas Paul; Ahmed-Kristensen, Saeema

2016-01-01

Selecting key performance indicators in conventional product development is a challenging task for project management and is compound by global product development. Informed from the findings of two in depth case studies conducted with large Danish manufacturing companies, in this paper we develo...

Sex differences in task distribution and task exposures among Danish house painters:

DEFF Research Database (Denmark)

Heilskov-Hansen, Thomas; Svendsen, Susanne Wulff; Thomsen, Jane Frølund

2014-01-01

OBJECTIVES: Sex differences in occupational biomechanical exposures may be part of the explanation why musculoskeletal complaints and disorders tend to be more common among women than among men. We aimed to determine possible sex differences in task distribution and task-specific postures...... correction were used to evaluate sex differences. RESULTS: Statistically significant (psex differences were revealed in task proportions, but the proportions differed by less than 4%. For task exposures, no statistically significant sex differences were found. CONCLUSIONS: Only minor sex differences...... and movements of the upper extremities among Danish house painters, and to establish sex-specific task exposure matrices. METHODS: To obtain task distributions, we sent out a questionnaire to all members of the Painters' Union in Denmark (N = 9364), of whom 53% responded. Respondents reported their task...

The Effect of a Workload-Preview on Task-Prioritization and Task-Performance

Science.gov (United States)

Minotra, Dev

2012-01-01

With increased volume and sophistication of cyber attacks in recent years, maintaining situation awareness and effective task-prioritization strategy is critical to the task of cybersecurity analysts. However, high levels of mental-workload associated with the task of cybersecurity analyst's limits their ability to prioritize tasks.…

Developmental Course of Conversational Behaviour of Children with 22q11.2 Deletion Syndrome and Williams Syndrome

Science.gov (United States)

Van Den Heuvel, Ellen; Botting, Nicola; Boudewijns, Inge; Manders, Eric; Swillen, Ann; Zink, Inge

2017-01-01

This study investigated three conversational subskills in children with 22q11.2 deletion syndrome (22q11.2DS, n = 8, ages 7-13) and Williams syndrome (WS, n = 8, ages 6-12). The researchers re-evaluated these subskills after 18 to 24 months and compared them to those of peers with idiopathic intellectual disability (IID) and IID and comorbid…

Exploring relations between task conflict and informational conflict in the Stroop task.

Science.gov (United States)

Entel, Olga; Tzelgov, Joseph; Bereby-Meyer, Yoella; Shahar, Nitzan

2015-11-01

In this study, we tested the proposal that the Stroop task involves two conflicts--task conflict and informational conflict. Task conflict was defined as the latency difference between color words and non-letter neutrals, and manipulated by varying the proportion of color words versus non-letter neutrals. Informational conflict was defined as the latency difference between incongruent and congruent trials and manipulated by varying the congruent-to-incongruent trial ratio. We replicated previous findings showing that increasing the ratio of incongruent-to-congruent trials reduces the latency difference between the incongruent and congruent condition (i.e., informational conflict), as does increasing the proportion of color words (i.e., task conflict). A significant under-additive interaction between the two proportion manipulations (congruent vs. incongruent and color words vs. neutrals) indicated that the effects of task conflict and informational conflict were not additive. By assessing task conflict as the contrast between color words and neutrals, we found that task conflict existed in all of our experimental conditions. Under specific conditions, when task conflict dominated behavior by explaining most of the variability between congruency conditions, we also found negative facilitation, thus demonstrating that this effect is a special case of task conflict.

Investigating Perfect Timesharing: The Relationship between IM-Compatible Tasks and Dual-Task Performance

Science.gov (United States)

Halvorson, Kimberly M.; Ebner, Herschel; Hazeltine, Eliot

2013-01-01

Why are dual-task costs reduced with ideomotor (IM) compatible tasks (Greenwald & Shulman, 1973; Lien, Proctor & Allen, 2002)? In the present experiments, we first examine three different measures of single-task performance (pure single-task blocks, mixed blocks, and long stimulus onset asynchrony [SOA] trials in dual-task blocks) and two…

Microprocessor multi-task monitor

International Nuclear Information System (INIS)

Ludemann, C.A.

1983-01-01

This paper describes a multi-task monitor program for microprocessors. Although written for the Intel 8085, it incorporates features that would be beneficial for implementation in other microprocessors used in controlling and monitoring experiments and accelerators. The monitor places permanent programs (tasks) arbitrarily located throughout ROM in a priority ordered queue. The programmer is provided with the flexibility to add new tasks or modified versions of existing tasks, without having to comply with previously defined task boundaries or having to reprogram all of ROM. Scheduling of tasks is triggered by timers, outside stimuli (interrupts), or inter-task communications. Context switching time is of the order of tenths of a milllisecond

An evaluation of the production effects of video self-modeling.

Science.gov (United States)

O'Handley, Roderick D; Allen, Keith D

2017-12-01

A multiple baseline across tasks design was used to evaluate the production effects of video self-modeling on three activities of daily living tasks of an adult male with Autism Spectrum Disorder and Intellectual Disability. Results indicated large increases in task accuracy after the production of a self-modeling video for each task, but before the video was viewed by the participant. Results also indicated small increases when the participant was directed to view the same video self-models before being prompted to complete each task. Copyright © 2017 Elsevier Ltd. All rights reserved.

Strategic Adaptation to Task Characteristics, Incentives, and Individual Differences in Dual-Tasking.

Directory of Open Access Journals (Sweden)

Christian P Janssen

Full Text Available We investigate how good people are at multitasking by comparing behavior to a prediction of the optimal strategy for dividing attention between two concurrent tasks. In our experiment, 24 participants had to interleave entering digits on a keyboard with controlling a randomly moving cursor with a joystick. The difficulty of the tracking task was systematically varied as a within-subjects factor. Participants were also exposed to different explicit reward functions that varied the relative importance of the tracking task relative to the typing task (between-subjects. Results demonstrate that these changes in task characteristics and monetary incentives, together with individual differences in typing ability, influenced how participants choose to interleave tasks. This change in strategy then affected their performance on each task. A computational cognitive model was used to predict performance for a wide set of alternative strategies for how participants might have possibly interleaved tasks. This allowed for predictions of optimal performance to be derived, given the constraints placed on performance by the task and cognition. A comparison of human behavior with the predicted optimal strategy shows that participants behaved near optimally. Our findings have implications for the design and evaluation of technology for multitasking situations, as consideration should be given to the characteristics of the task, but also to how different users might use technology depending on their individual characteristics and their priorities.

78 FR 63208 - UPDATE-Meeting of the Community Preventive Services Task Force (Task Force)

Science.gov (United States)

2013-10-23

... of the Community Preventive Services Task Force (Task Force) AGENCY: Centers for Disease Control and... Community Preventive Services Task Force (Task Force). The in-person Task Force meeting is being replaced by... CDC's ability to complete the necessary scientific and logistical support for the meeting. The Task...

Influence of time pressure in a simple response task, a choice-by-location task, and the Simon task

NARCIS (Netherlands)

van der Lubbe, Robert Henricus Johannes; Jaśkowski, Piotr; Wauschkuhn, Bernd; Verleger, Rolf

2001-01-01

Examined the influence of strategy for a simple response task, a choice-by-location task, and the Simon task by varying time pressure in 11 Ss (mean age 28 yrs). Besides reaction time (RT) and accuracy, we measured response force and derived two measures from the event-related EEG potential to form

Task complexity, student perceptions of vocabulary learning in EFL, and task performance.

Science.gov (United States)

Wu, Xiaoli; Lowyck, Joost; Sercu, Lies; Elen, Jan

2013-03-01

The study deepened our understanding of how students' self-efficacy beliefs contribute to the context of teaching English as a foreign language in the framework of cognitive mediational paradigm at a fine-tuned task-specific level. The aim was to examine the relationship among task complexity, self-efficacy beliefs, domain-related prior knowledge, learning strategy use, and task performance as they were applied to English vocabulary learning from reading tasks. Participants were 120 second-year university students (mean age 21) from a Chinese university. This experiment had two conditions (simple/complex). A vocabulary level test was first conducted to measure participants' prior knowledge of English vocabulary. Participants were then randomly assigned to one of the learning tasks. Participants were administered task booklets together with the self-efficacy scales, measures of learning strategy use, and post-tests. Data obtained were submitted to multivariate analysis of variance (MANOVA) and path analysis. Results from the MANOVA model showed a significant effect of vocabulary level on self-efficacy beliefs, learning strategy use, and task performance. Task complexity showed no significant effect; however, an interaction effect between vocabulary level and task complexity emerged. Results from the path analysis showed self-efficacy beliefs had an indirect effect on performance. Our results highlighted the mediating role of self-efficacy beliefs and learning strategy use. Our findings indicate that students' prior knowledge plays a crucial role on both self-efficacy beliefs and task performance, and the predictive power of self-efficacy on task performance may lie in its association with learning strategy use. © 2011 The British Psychological Society.

The functional neuroanatomy of multitasking: combining dual tasking with a short term memory task.

Science.gov (United States)

Deprez, Sabine; Vandenbulcke, Mathieu; Peeters, Ron; Emsell, Louise; Amant, Frederic; Sunaert, Stefan

2013-09-01

Insight into the neural architecture of multitasking is crucial when investigating the pathophysiology of multitasking deficits in clinical populations. Presently, little is known about how the brain combines dual-tasking with a concurrent short-term memory task, despite the relevance of this mental operation in daily life and the frequency of complaints related to this process, in disease. In this study we aimed to examine how the brain responds when a memory task is added to dual-tasking. Thirty-three right-handed healthy volunteers (20 females, mean age 39.9 ± 5.8) were examined with functional brain imaging (fMRI). The paradigm consisted of two cross-modal single tasks (a visual and auditory temporal same-different task with short delay), a dual-task combining both single tasks simultaneously and a multi-task condition, combining the dual-task with an additional short-term memory task (temporal same-different visual task with long delay). Dual-tasking compared to both individual visual and auditory single tasks activated a predominantly right-sided fronto-parietal network and the cerebellum. When adding the additional short-term memory task, a larger and more bilateral frontoparietal network was recruited. We found enhanced activity during multitasking in components of the network that were already involved in dual-tasking, suggesting increased working memory demands, as well as recruitment of multitask-specific components including areas that are likely to be involved in online holding of visual stimuli in short-term memory such as occipito-temporal cortex. These results confirm concurrent neural processing of a visual short-term memory task during dual-tasking and provide evidence for an effective fMRI multitasking paradigm. © 2013 Elsevier Ltd. All rights reserved.

Optimal task mapping in safety-critical real-time parallel systems

International Nuclear Information System (INIS)

Aussagues, Ch.

1998-01-01

This PhD thesis is dealing with the correct design of safety-critical real-time parallel systems. Such systems constitutes a fundamental part of high-performance systems for command and control that can be found in the nuclear domain or more generally in parallel embedded systems. The verification of their temporal correctness is the core of this thesis. our contribution is mainly in the following three points: the analysis and extension of a programming model for such real-time parallel systems; the proposal of an original method based on a new operator of synchronized product of state machines task-graphs; the validation of the approach by its implementation and evaluation. The work addresses particularly the main problem of optimal task mapping on a parallel architecture, such that the temporal constraints are globally guaranteed, i.e. the timeliness property is valid. The results incorporate also optimally criteria for the sizing and correct dimensioning of a parallel system, for instance in the number of processing elements. These criteria are connected with operational constraints of the application domain. Our approach is based on the off-line analysis of the feasibility of the deadline-driven dynamic scheduling that is used to schedule tasks inside one processor. This leads us to define the synchronized-product, a system of linear, constraints is automatically generated and then allows to calculate a maximum load of a group of tasks and then to verify their timeliness constraints. The communications, their timeliness verification and incorporation to the mapping problem is the second main contribution of this thesis. FInally, the global solving technique dealing with both task and communication aspects has been implemented and evaluated in the framework of the OASIS project in the LETI research center at the CEA/Saclay. (author)

The effects of dual tasking on handwriting in patients with Parkinson's disease.

Science.gov (United States)

Broeder, S; Nackaerts, E; Nieuwboer, A; Smits-Engelsman, B C M; Swinnen, S P; Heremans, E

2014-03-28

Previous studies have shown that patients with Parkinson's disease (PD) experience extensive problems during dual tasking. Up to now, dual-task interference in PD has mainly been investigated in the context of gait research. However, the simultaneous performance of two different tasks is also a prerequisite to efficiently perform many other tasks in daily life, including upper limb tasks. To address this issue, this study investigated the effect of a secondary cognitive task on the performance of handwriting in patients with PD. Eighteen PD patients and 11 age-matched controls performed a writing task involving the production of repetitive loops under single- and dual-task conditions. The secondary task consisted of counting high and low tones during writing. The writing tests were performed with two amplitudes (0.6 and 1.0cm) using a writing tablet. Results showed that dual-task performance was affected in PD patients versus controls. Dual tasking reduced writing amplitude in PD patients, but not in healthy controls (p=0.046). Patients' writing size was mainly reduced during the small-amplitude condition (small amplitude p=0.017; large amplitude p=0.310). This suggests that the control of writing at small amplitudes requires more compensational brain-processing recourses in PD and is as such less automatic than writing at large amplitudes. In addition, there was a larger dual-task effect on the secondary task in PD patients than controls (p=0.025). The writing tests on the writing tablet proved highly correlated to daily life writing as measured by the 'Systematic Screening of Handwriting Difficulties' test (SOS-test) and other manual dexterity tasks, particularly during dual-task conditions. Taken together, these results provide additional insights into the motor control of handwriting and the effects of dual tasking during upper limb movements in patients with PD. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Correlates of academic procrastination: discomfort, task aversiveness, and task capability.

Science.gov (United States)

Milgram, N; Marshevsky, S; Sadeh, C

1995-03-01

The relationships among five aspects of academic procrastination--behavioral delay, personal upset about the delay, task aversiveness, task capability, and the desire to reduce behavioral delay--were investigated in 10th-grade Israeli students (N = 195). Upset about delay was weakly related to delay itself, and--unlike delay--was strongly related to perceived capability to perform academic tasks and to the desire to change delaying behavior. Students delayed more on academic tasks labeled unpleasant than pleasant, were neutral in between, and were correspondingly more upset about the former than the latter. They more frequently acknowledged reasons for academic procrastination that were less threatening to their self-image (e.g., problems in time management) than reasons that were more threatening (e.g., lack of ability). Interest in reducing delay is related more to self-perceived ability to handle tasks than to time spent procrastinating or reasons given for procrastinating.

Estimating demand for alternatives to cigarettes with online purchase tasks.

Science.gov (United States)

O'Connor, Richard J; June, Kristie M; Bansal-Travers, Maansi; Rousu, Matthew C; Thrasher, James F; Hyland, Andrew; Cummings, K Michael

2014-01-01

To explore how advertising affects demand for cigarettes and potential substitutes, including snus, dissolvable tobacco, and medicinal nicotine. A Web-based experiment randomized 1062 smokers to see advertisements for alternative nicotine products or soft drinks, then complete a series of purchase tasks, which were used to estimate demand elasticity, peak consumption, and cross-price elasticity (CPE) for tobacco products. Lower demand elasticity and greater peak consumption were seen for cigarettes compared to all alternative products (p demand. These findings suggest significantly lower demand for alternative nicotine sources among smokers than previously revealed.

Advances in chemical product design

DEFF Research Database (Denmark)

Zhang, Lei; Fung, Ka Yip; Wibowo, Christianto

2018-01-01

The nature of chemical product design problems is diverse and multidisciplinary. It involves many design issues such as project management, market study, product design, process design, and economic analysis for better organizing the product design project and achieving better products. This arti......The nature of chemical product design problems is diverse and multidisciplinary. It involves many design issues such as project management, market study, product design, process design, and economic analysis for better organizing the product design project and achieving better products....... This article provides an overview of chemical product design with a multidisciplinary hierarchical framework including all the design issues and tasks. Each of the design issues and tasks are introduced and discussed, methods and tools are summarized and compared, challenges and perspectives are presented...... to help the chemical product design researchers on finding more novel, innovative and sustainable products, by the combined effort from academia and industry to develop a systematic generic framework, and tools including product simulator, process simulator, database manager, modeling tool, and templates...

The effect analysis of mediation variable of task productivity on the self-efficacy and employees’ performance

Directory of Open Access Journals (Sweden)

Annissa Chairum Soebandono

2016-11-01

Full Text Available This research was conducted for analyzing the effect of mediating variable that is individual task proactivity as one of the proactivities of behavior towards the relationship between self-efficacy and the employees’ performance in the logistics companies of shipping the goods. It uses convenience sampling, which is a non-probability sampling method for getting the sample of 52 employees. They were divided into two divisions, namely infrastructure and quality assurance. The questionnaire consists of two parts, in which some were assessed by themselves and others that were assessed by the supervisor. They were analyzed using path analysis using analytical tools developed by Hayes, Preacher-Hayes with the simple mediation models. It was found that employees have self-efficacy, individual task proactivity, and relatively high performance, in which individual task proactivity can be a mediating variable on the effect self-efficacy on performance.

"Photographing money" task pricing

Science.gov (United States)

Jia, Zhongxiang

2018-05-01

"Photographing money" [1]is a self-service model under the mobile Internet. The task pricing is reasonable, related to the success of the commodity inspection. First of all, we analyzed the position of the mission and the membership, and introduced the factor of membership density, considering the influence of the number of members around the mission on the pricing. Multivariate regression of task location and membership density using MATLAB to establish the mathematical model of task pricing. At the same time, we can see from the life experience that membership reputation and the intensity of the task will also affect the pricing, and the data of the task success point is more reliable. Therefore, the successful point of the task is selected, and its reputation, task density, membership density and Multiple regression of task positions, according to which a nhew task pricing program. Finally, an objective evaluation is given of the advantages and disadvantages of the established model and solution method, and the improved method is pointed out.

Board Task Performance

DEFF Research Database (Denmark)

Minichilli, Alessandro; Zattoni, Alessandro; Nielsen, Sabina

2012-01-01

identify three board processes as micro-level determinants of board effectiveness. Specifically, we focus on effort norms, cognitive conflicts and the use of knowledge and skills as determinants of board control and advisory task performance. Further, we consider how two different institutional settings....... The findings show that: (i) Board processes have a larger potential than demographic variables to explain board task performance; (ii) board task performance differs significantly between boards operating in different contexts; and (iii) national context moderates the relationships between board processes...... and board task performance....

A Method of Numerical Control Equipment Appearance Design Based on Product Identity

Science.gov (United States)

Zhu, Zhijuan; Zhou, Qi; Li, Bin; Visser, Steve

Research on numerical control (NC) equipment has been more and more abundant; however, there are few existing studies in the field of appearance design for NC equipments. This paper provided a method to generate new appearance design of NC equipments based on product identity (PI). For the purpose of providing guidelines to generate new concept of NC equipment design, this paper, therefore, took the DMG Company (a Germen NC equipment company) as a case, examined the total products of this company from two aspects: Product Image and Product Family. Task 1 was an evaluate task about the Product Image by using the semantic differential (SD) evaluation method; Task 2 was a study task about Product Family to find out features of the products and classify these features. During the Task 2, several features have been found out and summarized, and these features were classified into 3 different levels according to their frequency and importance. In the end, two appearance design samples have been generated based on the analysis above to prove the application of the research.

A new semantic vigilance task: vigilance decrement, workload, and sensitivity to dual-task costs.

Science.gov (United States)

Epling, Samantha L; Russell, Paul N; Helton, William S

2016-01-01

Cognitive resource theory is a common explanation for both the performance decline in vigilance tasks, known as the vigilance decrement, and the limited ability to perform multiple tasks simultaneously. The limited supply of cognitive resources may be utilized faster than they are replenished resulting in a performance decrement, or may need to be allocated among multiple tasks with some performance cost. Researchers have proposed both domain-specific, for example spatial versus verbal processing resources, and domain general cognitive resources. One challenge in testing the domain specificity of cognitive resources in vigilance is the current lack of difficult semantic vigilance tasks which reliably produce a decrement. In the present research, we investigated whether the vigilance decrement was found in a new abbreviated semantic discrimination vigilance task, and whether there was a performance decrement in said vigilance task when paired with a word recall task, as opposed to performed individually. As hypothesized, a vigilance decrement in the semantic vigilance task was found in both the single-task and dual-task conditions, along with reduced vigilance performance in the dual-task condition and reduced word recall in the dual-task condition. This is consistent with cognitive resource theory. The abbreviated semantic vigilance task will be a useful tool for researchers interested in determining the specificity of cognitive resources utilized in vigilance tasks.

Mood states determine the degree of task shielding in dual-task performance.

Science.gov (United States)

Zwosta, Katharina; Hommel, Bernhard; Goschke, Thomas; Fischer, Rico

2013-01-01

Current models of multitasking assume that dual-task performance and the degree of multitasking are affected by cognitive control strategies. In particular, cognitive control is assumed to regulate the amount of shielding of the prioritised task from crosstalk from the secondary task. We investigated whether and how task shielding is influenced by mood states. Participants were exposed to two short film clips, one inducing high and one inducing low arousal, of either negative or positive content. Negative mood led to stronger shielding of the prioritised task (i.e., less crosstalk) than positive mood, irrespective of arousal. These findings support the assumption that emotional states determine the parameters of cognitive control and play an important role in regulating dual-task performance.

Brain activations during bimodal dual tasks depend on the nature and combination of component tasks

Directory of Open Access Journals (Sweden)

Emma eSalo

2015-02-01

Full Text Available We used functional magnetic resonance imaging to investigate brain activations during nine different dual tasks in which the participants were required to simultaneously attend to concurrent streams of spoken syllables and written letters. They performed a phonological, spatial or simple (speaker-gender or font-shade discrimination task within each modality. We expected to find activations associated specifically with dual tasking especially in the frontal and parietal cortices. However, no brain areas showed systematic dual task enhancements common for all dual tasks. Further analysis revealed that dual tasks including component tasks that were according to Baddeley’s model modality atypical, that is, the auditory spatial task or the visual phonological task, were not associated with enhanced frontal activity. In contrast, for other dual tasks, activity specifically associated with dual tasking was found in the left or bilateral frontal cortices. Enhanced activation in parietal areas, however, appeared not to be specifically associated with dual tasking per se, but rather with intermodal attention switching. We also expected effects of dual tasking in left frontal supramodal phonological processing areas when both component tasks required phonological processing and in right parietal supramodal spatial processing areas when both tasks required spatial processing. However, no such effects were found during these dual tasks compared with their component tasks performed separately. Taken together, the current results indicate that activations during dual tasks depend in a complex manner on specific demands of component tasks.

The predictive value of general movement tasks in assessing occupational task performance.

Science.gov (United States)

Frost, David M; Beach, Tyson A C; McGill, Stuart M; Callaghan, Jack P

2015-01-01

Within the context of evaluating individuals' movement behavior it is generally assumed that the tasks chosen will predict their competency to perform activities relevant to their occupation. This study sought to examine whether a battery of general tasks could be used to predict the movement patterns employed by firefighters to perform select job-specific skills. Fifty-two firefighters performed a battery of general and occupation-specific tasks that simulated the demands of firefighting. Participants' peak lumbar spine and frontal plane knee motion were compared across tasks. During 85% of all comparisons, the magnitude of spine and knee motion was greater during the general movement tasks than observed during the firefighting skills. Certain features of a worker's movement behavior may be exhibited across a range of tasks. Therefore, provided that a movement screen's tasks expose the motions of relevance for the population being tested, general evaluations could offer valuable insight into workers' movement competency or facilitate an opportunity to establish an evidence-informed intervention.

Articulatory Control in Childhood Apraxia of Speech in a Novel Word-Learning Task

Science.gov (United States)

Case, Julie; Grigos, Maria I.

2016-01-01

Purpose: Articulatory control and speech production accuracy were examined in children with childhood apraxia of speech (CAS) and typically developing (TD) controls within a novel word-learning task to better understand the influence of planning and programming deficits in the production of unfamiliar words. Method: Participants included 16…

Inpo/industry job and task analysis efforts

International Nuclear Information System (INIS)

Wigley, W.W.

1985-01-01

One of the goals of INPO is to develop and coordinate industrywide programs to improve the education, training and qualification of nuclear utility personnel. To accomplish this goal, INPO's Training and Education Division: conducts periodic evaluations of industry training programs; provides assistance to the industry in developing training programs; manages the accreditation of utility training programs. These efforts are aimed at satisfying the need for training programs for nuclear utility personnel to be performance-based. Performance-based means that training programs provide an incumbent with the skills and knowledge required to safely perform the job. One of the ways that INPO has provided assistance to the industry is through the industrywide job and task analysis effort. I will discuss the job analysis and task analysis processes, the current status of JTA efforts, JTA products and JTA lessons learned

Task conflict and proactive control: A computational theory of the Stroop task.

Science.gov (United States)

Kalanthroff, Eyal; Davelaar, Eddy J; Henik, Avishai; Goldfarb, Liat; Usher, Marius

2018-01-01

The Stroop task is a central experimental paradigm used to probe cognitive control by measuring the ability of participants to selectively attend to task-relevant information and inhibit automatic task-irrelevant responses. Research has revealed variability in both experimental manipulations and individual differences. Here, we focus on a particular source of Stroop variability, the reverse-facilitation (RF; faster responses to nonword neutral stimuli than to congruent stimuli), which has recently been suggested as a signature of task conflict. We first review the literature that shows RF variability in the Stroop task, both with regard to experimental manipulations and to individual differences. We suggest that task conflict variability can be understood as resulting from the degree of proactive control that subjects recruit in advance of the Stroop stimulus. When the proactive control is high, task conflict does not arise (or is resolved very quickly), resulting in regular Stroop facilitation. When proactive control is low, task conflict emerges, leading to a slow-down in congruent and incongruent (but not in neutral) trials and thus to Stroop RF. To support this suggestion, we present a computational model of the Stroop task, which includes the resolution of task conflict and its modulation by proactive control. Results show that our model (a) accounts for the variability in Stroop-RF reported in the experimental literature, and (b) solves a challenge to previous Stroop models-their ability to account for reaction time distributional properties. Finally, we discuss theoretical implications to Stroop measures and control deficits observed in some psychopathologies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Planning and task management in Parkinson's disease: differential emphasis in dual-task performance.

Science.gov (United States)

Bialystok, Ellen; Craik, Fergus I M; Stefurak, Taresa

2008-03-01

Seventeen patients diagnosed with Parkinson's disease completed a complex computer-based task that involved planning and management while also performing an attention-demanding secondary task. The tasks were performed concurrently, but it was necessary to switch from one to the other. Performance was compared to a group of healthy age-matched control participants and a group of young participants. Parkinson's patients performed better than the age-matched controls on almost all measures and as well as the young controls in many cases. However, the Parkinson's patients achieved this by paying relatively less attention to the secondary task and focusing attention more on the primary task. Thus, Parkinson's patients can apparently improve their performance on some aspects of a multidimensional task by simplifying task demands. This benefit may occur as a consequence of their inflexible exaggerated attention to some aspects of a complex task to the relative neglect of other aspects.

Stability, performance and sensitivity analysis of I.I.D. jump linear systems

Science.gov (United States)

Chávez Fuentes, Jorge R.; González, Oscar R.; Gray, W. Steven

2018-06-01

This paper presents a symmetric Kronecker product analysis of independent and identically distributed jump linear systems to develop new, lower dimensional equations for the stability and performance analysis of this type of systems than what is currently available. In addition, new closed form expressions characterising multi-parameter relative sensitivity functions for performance metrics are introduced. The analysis technique is illustrated with a distributed fault-tolerant flight control example where the communication links are allowed to fail randomly.

The Applicability of Rhythm-Motor Tasks to a New Dual Task Paradigm for Older Adults

Directory of Open Access Journals (Sweden)

Soo Ji Kim

2017-12-01

Full Text Available Given the interplay between cognitive and motor functions during walking, cognitive demands required during gait have been investigated with regard to dual task performance. Along with the needs to understand how the type of concurrent task while walking affects gait performance, there are calls for diversified dual tasks that can be applied to older adults with varying levels of cognitive decline. Therefore, this study aimed to examine how rhythm-motor tasks affect dual task performance and gait control, compared to a traditional cognitive-motor task. Also, it examined whether rhythm-motor tasks are correlated with traditional cognitive-motor task performance and cognitive measures. Eighteen older adults without cognitive impairment participated in this study. Each participant was instructed to walk at self-paced tempo without performing a concurrent task (single walking task and walk while separately performing two types of concurrent tasks: rhythm-motor and cognitive-motor tasks. Rhythm-motor tasks included instrument playing (WalkIP, matching to rhythmic cueing (WalkRC, and instrument playing while matching to rhythmic cueing (WalkIP+RC. The cognitive-motor task involved counting forward by 3s (WalkCount.f3. In each condition, dual task costs (DTC, a measure for how dual tasks affect gait parameters, were measured in terms of walking speed and stride length. The ratio of stride length to walking speed, a measure for dynamic control of gait, was also examined. The results of this study demonstrated that the task type was found to significantly influence these measures. Rhythm-motor tasks were found to interfere with gait parameters to a lesser extent than the cognitive-motor task (WalkCount.f3. In terms of ratio measures, stride length remained at a similar level, walking speed greatly decreased in the WalkCount.f3 condition. Significant correlations between dual task-related measures during rhythm-motor and cognitive-motor tasks support the

Final Report on ITER Task Agreement 81-08

Energy Technology Data Exchange (ETDEWEB)

Richard L. Moore

2008-03-01

As part of an ITER Implementing Task Agreement (ITA) between the ITER US Participant Team (PT) and the ITER International Team (IT), the INL Fusion Safety Program was tasked to provide the ITER IT with upgrades to the fusion version of the MELCOR 1.8.5 code including a beryllium dust oxidation model. The purpose of this model is to allow the ITER IT to investigate hydrogen production from beryllium dust layers on hot surfaces inside the ITER vacuum vessel (VV) during in-vessel loss-of-cooling accidents (LOCAs). Also included in the ITER ITA was a task to construct a RELAP5/ATHENA model of the ITER divertor cooling loop to model the draining of the loop during a large ex-vessel pipe break followed by an in-vessel divertor break and compare the results to a simular MELCOR model developed by the ITER IT. This report, which is the final report for this agreement, documents the completion of the work scope under this ITER TA, designated as TA 81-08.

The Task Is Not Enough: Processing Approaches to Task-Based Performance

Science.gov (United States)

Skehan, Peter; Xiaoyue, Bei; Qian, Li; Wang, Zhan

2012-01-01

This article reports on three research studies, all of which concern second language task performance. The first focuses on planning, and compares on-line and strategic planning as well as task repetition. The second study examines the role of familiarity on task performance, and compares this with conventional strategic planning. The third study…

Single-task and dual-task tandem gait test performance after concussion.

Science.gov (United States)

Howell, David R; Osternig, Louis R; Chou, Li-Shan

2017-07-01

To compare single-task and dual-task tandem gait test performance between athletes after concussion with controls on observer-timed, spatio-temporal, and center-of-mass (COM) balance control measurements. Ten participants (19.0±5.5years) were prospectively identified and completed a tandem gait test protocol within 72h of concussion and again 1 week, 2 weeks, 1 month, and 2 months post-injury. Seven uninjured controls (20.0±4.5years) completed the same protocol in similar time increments. Tandem gait test trials were performed with (dual-task) and without (single-task) concurrently performing a cognitive test as whole-body motion analysis was performed. Outcome variables included test completion time, average tandem gait velocity, cadence, and whole-body COM frontal plane displacement. Concussion participants took significantly longer to complete the dual-task tandem gait test than controls throughout the first 2 weeks post-injury (mean time=16.4 [95% CI: 13.4-19.4] vs. 10.1 [95% CI: 6.4-13.7] seconds; p=0.03). Single-task tandem gait times were significantly lower 72h post-injury (p=0.04). Dual-task cadence was significantly lower for concussion participants than controls (89.5 [95% CI: 68.6-110.4] vs. 127.0 [95% CI: 97.4-156.6] steps/minute; p=0.04). Moderately-high to high correlations between tandem gait test time and whole-body COM medial-lateral displacement were detected at each time point during dual-task gait (r s =0.70-0.93; p=0.03-0.001). Adding a cognitive task during the tandem gait test resulted in longer detectable deficits post-concussion compared to the traditional single-task tandem gait test. As a clinical tool to assess dynamic motor function, tandem gait may assist with return to sport decisions after concussion. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

When predictions take control: The effect of task predictions on task switching performance

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Wout eDuthoo

2012-08-01

Full Text Available In this paper, we aimed to investigate the role of self-generated predictions in the flexible control of behaviour. Therefore, we ran a task switching experiment in which participants were asked to try to predict the upcoming task in three conditions varying in switch rate (30%, 50% and 70%. Irrespective of their predictions, the colour of the target indicated which task participants had to perform. In line with previous studies (Mayr, 2006; Monsell & Mizon, 2006, the switch cost was attenuated as the switch rate increased. Importantly, a clear task repetition bias was found in all conditions, yet the task repetition prediction rate dropped from 78% over 66% to 49% with increasing switch probability in the three conditions. Irrespective of condition, the switch cost was strongly reduced in expectation of a task alternation compared to the cost of an unexpected task alternation following repetition predictions. Hence, our data suggest that the reduction in the switch cost with increasing switch probability is caused by a diminished expectancy for the task to repeat. Taken together, this paper highlights the importance of predictions in the flexible control of behaviour, and suggests a crucial role for task repetition expectancy in the context-sensitive adjusting of task switching performance.

Quantitative assessment of airborne exposures generated during common cleaning tasks: a pilot study

Directory of Open Access Journals (Sweden)

Perry Melissa J

2010-11-01

Full Text Available Abstract Background A growing body of epidemiologic evidence suggests an association between exposure to cleaning products with asthma and other respiratory disorders. Thus far, these studies have conducted only limited quantitative exposure assessments. Exposures from cleaning products are difficult to measure because they are complex mixtures of chemicals with a range of physicochemical properties, thus requiring multiple measurement techniques. We conducted a pilot exposure assessment study to identify methods for assessing short term, task-based airborne exposures and to quantitatively evaluate airborne exposures associated with cleaning tasks simulated under controlled work environment conditions. Methods Sink, mirror, and toilet bowl cleaning tasks were simulated in a large ventilated bathroom and a small unventilated bathroom using a general purpose, a glass, and a bathroom cleaner. All tasks were performed for 10 minutes. Airborne total volatile organic compounds (TVOC generated during the tasks were measured using a direct reading instrument (DRI with a photo ionization detector. Volatile organic ingredients of the cleaning mixtures were assessed utilizing an integrated sampling and analytic method, EPA TO-17. Ammonia air concentrations were also measured with an electrochemical sensor embedded in the DRI. Results Average TVOC concentrations calculated for 10 minute tasks ranged 0.02 - 6.49 ppm and the highest peak concentrations observed ranged 0.14-11 ppm. TVOC time concentration profiles indicated that exposures above background level remained present for about 20 minutes after cessation of the tasks. Among several targeted VOC compounds from cleaning mixtures, only 2-BE was detectable with the EPA method. The ten minute average 2- BE concentrations ranged 0.30 -21 ppm between tasks. The DRI underestimated 2-BE exposures compared to the results from the integrated method. The highest concentration of ammonia of 2.8 ppm occurred

On the importance of Task 1 and error performance measures in PRP dual-task studies

Science.gov (United States)

Strobach, Tilo; Schütz, Anja; Schubert, Torsten

2015-01-01

The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects. PMID:25904890

On the importance of Task 1 and error performance measures in PRP dual-task studies.

Science.gov (United States)

Strobach, Tilo; Schütz, Anja; Schubert, Torsten

2015-01-01

The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.

Blue or red? Exploring the effect of color on cognitive task performances.

Science.gov (United States)

Mehta, Ravi; Zhu, Rui Juliet

2009-02-27

Existing research reports inconsistent findings with regard to the effect of color on cognitive task performances. Some research suggests that blue or green leads to better performances than red; other studies record the opposite. Current work reconciles this discrepancy. We demonstrate that red (versus blue) color induces primarily an avoidance (versus approach) motivation (study 1, n = 69) and that red enhances performance on a detail-oriented task, whereas blue enhances performance on a creative task (studies 2 and 3, n = 208 and 118). Further, we replicate these results in the domains of product design (study 4, n = 42) and persuasive message evaluation (study 5, n = 161) and show that these effects occur outside of individuals' consciousness (study 6, n = 68). We also provide process evidence suggesting that the activation of alternative motivations mediates the effect of color on cognitive task performances.

Localizing semantic interference from distractor sounds in picture naming: A dual-task study.

Science.gov (United States)

Mädebach, Andreas; Kieseler, Marie-Luise; Jescheniak, Jörg D

2017-10-13

In this study we explored the locus of semantic interference in a novel picture-sound interference task in which participants name pictures while ignoring environmental distractor sounds. In a previous study using this task (Mädebach, Wöhner, Kieseler, & Jescheniak, in Journal of Experimental Psychology: Human Perception and Performance, 43, 1629-1646, 2017), we showed that semantically related distractor sounds (e.g., BARKING dog ) interfere with a picture-naming response (e.g., "horse") more strongly than unrelated distractor sounds do (e.g., DRUMMING drum ). In the experiment reported here, we employed the psychological refractory period (PRP) approach to explore the locus of this effect. We combined a geometric form classification task (square vs. circle; Task 1) with the picture-sound interference task (Task 2). The stimulus onset asynchrony (SOA) between the tasks was systematically varied (0 vs. 500 ms). There were three central findings. First, the semantic interference effect from distractor sounds was replicated. Second, picture naming (in Task 2) was slower with the short than with the long task SOA. Third, both effects were additive-that is, the semantic interference effects were of similar magnitude at both task SOAs. This suggests that the interference arises during response selection or later stages, not during early perceptual processing. This finding corroborates the theory that semantic interference from distractor sounds reflects a competitive selection mechanism in word production.

Comparing 15D Valuation Studies in Norway and Finland-Challenges When Combining Information from Several Valuation Tasks.

Science.gov (United States)

Michel, Yvonne Anne; Augestad, Liv Ariane; Rand, Kim

2018-04-01

The 15D is a generic preference-based health-related quality-of-life instrument developed in Finland. Values for the 15D instrument are estimated by combining responses to three distinct valuation tasks. The impact of how these tasks are combined is relatively unexplored. To compare 15D valuation studies conducted in Norway and Finland in terms of scores assigned in the valuation tasks and resulting value algorithms, and to discuss the contributions of each task and the algorithm estimation procedure to observed differences. Norwegian and Finnish scores from the three valuation tasks were compared using independent samples t tests and Lin concordance correlation coefficients. Covariance between tasks was assessed using Pearson product-moment correlations. Norwegian and Finnish value algorithms were compared using concordance correlation coefficients, total ranges, and ranges for individual dimensions. Observed differences were assessed using minimal important difference. Mean scores in the main valuation task were strikingly similar between the two countries, whereas the final value algorithms were less similar. The largest differences between Norway and Finland were observed for depression, vision, and mental function. 15D algorithms are a product of combining scores from three valuation tasks by use of methods involving multiplication. This procedure used to combine scores from the three tasks by multiplication serves to amplify variance from each task. From relatively similar responses in Norway and Finland, diverging value algorithms are created. We propose to simplify the 15D algorithm estimation procedure by using only one of the valuation tasks. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

The Next Generation ATLAS Production System

CERN Document Server

Borodin, Mikhail; The ATLAS collaboration; Golubkov, Dmitry; Klimentov, Alexei; Maeno, Tadashi; Mashinistov, Ruslan; Vaniachine, Alexandre

2015-01-01

The ATLAS experiment at LHC data processing and simulation grows continuously, as more data and more use cases emerge. For data processing the ATLAS experiment adopted the data transformation approach, where software applications transform the input data into outputs. In the ATLAS production system, each data transformation is represented by a task, a collection of many jobs, dynamically submitted by the ATLAS workload management system (PanDA/JEDI) and executed on the Grid, clouds and supercomputers. Patterns in ATLAS data transformation workflows composed of many tasks provided a scalable production system framework for template definitions of the many-tasks workflows. User interface and system logic of these workflows are being implemented in the Database Engine for Tasks (DEFT). Such development required using modern computing technologies and approaches. We report technical details of this development: database implementation, server logic and Web user interface technologies.

On the importance of Task 1 and error performance measures in PRP dual-task studies

Directory of Open Access Journals (Sweden)

Tilo eStrobach

2015-04-01

Full Text Available The Psychological Refractory Period (PRP paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and 2 are presented with variable stimulus onset asynchronies (SOAs and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e. decreasing SOAs do not increase RTs and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/ or error rates in Task 1. This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.

Empirical Productivity Indices and Indicators

NARCIS (Netherlands)

B.M. Balk (Bert)

2016-01-01

textabstractThe empirical measurement of productivity change (or difference) by means of indices and indicators starts with the ex post profit/loss accounts of a production unit. Key concepts are profit, leading to indicators, and profitability, leading to indices. The main task for the productivity

Different Ways to Cue a Coherent Memory System: A Theory for Episodic, Semantic, and Procedural Tasks.

Science.gov (United States)

Humphreys, Michael S.; And Others

1989-01-01

An associative theory of memory is proposed to serve as a counterexample to claims that dissociations among episodic, semantic, and procedural memory tasks necessitate separate memory systems. The theory is based on task analyses of matching (recognition and familiarity judgments), retrieval (cued recall), and production (free association). (TJH)

Cognitive task load analysis : Allocating tasks and designing support

NARCIS (Netherlands)

Neerincx, M.A.

2003-01-01

We present a method for Cognitive Task Analysis that guides the early stages of software development, aiming at an optimal cognitive load for operators of process control systems. The method is based on a practical theory of cognitive task load and support. In addition to the classical measure

Overview of the ID, EPI and REL tasks of BioNLP Shared Task 2011

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Pyysalo Sampo

2012-06-01

Full Text Available Abstract We present the preparation, resources, results and analysis of three tasks of the BioNLP Shared Task 2011: the main tasks on Infectious Diseases (ID and Epigenetics and Post-translational Modifications (EPI, and the supporting task on Entity Relations (REL. The two main tasks represent extensions of the event extraction model introduced in the BioNLP Shared Task 2009 (ST'09 to two new areas of biomedical scientific literature, each motivated by the needs of specific biocuration tasks. The ID task concerns the molecular mechanisms of infection, virulence and resistance, focusing in particular on the functions of a class of signaling systems that are ubiquitous in bacteria. The EPI task is dedicated to the extraction of statements regarding chemical modifications of DNA and proteins, with particular emphasis on changes relating to the epigenetic control of gene expression. By contrast to these two application-oriented main tasks, the REL task seeks to support extraction in general by separating challenges relating to part-of relations into a subproblem that can be addressed by independent systems. Seven groups participated in each of the two main tasks and four groups in the supporting task. The participating systems indicated advances in the capability of event extraction methods and demonstrated generalization in many aspects: from abstracts to full texts, from previously considered subdomains to new ones, and from the ST'09 extraction targets to other entities and events. The highest performance achieved in the supporting task REL, 58% F-score, is broadly comparable with levels reported for other relation extraction tasks. For the ID task, the highest-performing system achieved 56% F-score, comparable to the state-of-the-art performance at the established ST'09 task. In the EPI task, the best result was 53% F-score for the full set of extraction targets and 69% F-score for a reduced set of core extraction targets, approaching a level

Exploiting impedance shaping approaches to overcome force overshoots in delicate interaction tasks

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Loris Roveda

2016-09-01

Full Text Available The aim of the presented article is to overcome the force overshoot issue in impedance based force tracking applications. Nowadays, light-weight manipulators are involved in high-accurate force control applications (such as polishing tasks, where the force overshoot issue is critical (i.e. damaging the component causing a production waste, exploiting the impedance control. Two main force tracking impedance control approaches are described in literature: (a set-point deformation and (b variable stiffness approaches. However, no contributions are directly related to the force overshoot issue. The presented article extends both such methodologies to analytically achieve the force overshoots avoidance in interaction tasks based on the on-line estimation of the interacting environment stiffness (available through an EKF. Both the proposed control algorithms allow to achieve a linear closed-loop dynamics for the coupled robot-environment system. Therefore, control gains can be analytically on-line calculated to achieve an over-damped closed-loop dynamics of the controlled coupled system. Control strategies have been validated in experiments, involving a KUKA LWR 4+. A probing task has been performed, representative of many industrial tasks (e.g. assembly tasks, in which a main force task direction is defined.

Mechanisms of Practice-Related Reductions of Dual-Task Interference with Simple Tasks: Data and Theory

Science.gov (United States)

Strobach, Tilo; Torsten, Schubert

2017-01-01

In dual-task situations, interference between two simultaneous tasks impairs performance. With practice, however, this impairment can be reduced. To identify mechanisms leading to a practice-related improvement in sensorimotor dual tasks, the present review applied the following general hypothesis: Sources that impair dual-task performance at the beginning of practice are associated with mechanisms for the reduction of dual-task impairment at the end of practice. The following types of processes provide sources for the occurrence of this impairment: (a) capacity-limited processes within the component tasks, such as response-selection or motor response stages, and (b) cognitive control processes independent of these tasks and thus operating outside of component-task performance. Dual-task practice studies show that, under very specific conditions, capacity-limited processes within the component tasks are automatized with practice, reducing the interference between two simultaneous tasks. Further, there is evidence that response-selection stages are shortened with practice. Thus, capacity limitations at these stages are sources for dual-task costs at the beginning of practice and are overcome with practice. However, there is no evidence demonstrating the existence of practice-related mechanisms associated with capacity-limited motor-response stages. Further, during practice, there is an acquisition of executive control skills for an improved allocation of limited attention resources to two tasks as well as some evidence supporting the assumption of improved task coordination. These latter mechanisms are associated with sources of dual-task interference operating outside of component task performance at the beginning of practice and also contribute to the reduction of dual-task interference at its end. PMID:28439319

IEA Agreement on the production and utilization of hydrogen: 1999 annual report

Energy Technology Data Exchange (ETDEWEB)

Elam, Carolyn C. (National Renewable Energy Lab, Golden, CO (US)) (ed.)

2000-01-31

The annual report begins with an overview of the IEA Hydrogen Agreement, including guiding principles and their strategic plan followed by the Chairman's report providing the year's highlights. Annex reports included are: the final report for Task 11, Integrated Systems; task updates for Task 12, Metal Hydrides and Carbon for Hydrogen Storage, Task 13, Design and Optimization of Integrated Systems, Task 14, Photoelectrolytic Production of Hydrogen, and Task 15, Photobiological Production of Hydrogen; and a feature article by Karsten Wurr titled 'Large-Scale Industrial Uses of Hydrogen: Final Development Report'.

Some Econometric Results for the Blanchard-Watson Bubble Model

DEFF Research Database (Denmark)

Johansen, Soren; Lange, Theis

The purpose of the present paper is to analyse a simple bubble model suggested by Blanchard and Watson. The model is defined by y(t) =s(t)¿y(t-1)+e(t), t=1,…,n, where s(t) is an i.i.d. binary variable with p=P(s(t)=1), independent of e(t) i.i.d. with mean zero and finite variance. We take ¿>1 so...

Peer Pressure in Multi-Dimensional Work Tasks

OpenAIRE

Felix Ebeling; Gerlinde Fellner; Johannes Wahlig

2012-01-01

We study the influence of peer pressure in multi-dimensional work tasks theoretically and in a controlled laboratory experiment. Thereby, workers face peer pressure in only one work dimension. We find that effort provision increases in the dimension where peer pressure is introduced. However, not all of this increase translates into a productivity gain, since the effect is partly offset by a decrease of effort in the work dimension without peer pressure. Furthermore, this tradeoff is stronger...

Self-Efficacy, Task Complexity and Task Performance: Exploring Interactions in Two Versions of Vocabulary Learning Tasks

Science.gov (United States)

Wu, Xiaoli; Lowyck, Joost; Sercu, Lies; Elen, Jan

2012-01-01

The present study aimed for better understanding of the interactions between task complexity and students' self-efficacy beliefs and students' use of learning strategies, and finally their interacting effects on task performance. This investigation was carried out in the context of Chinese students learning English as a foreign language in a…

The Effect of Written Corrective Feedback on the Accuracy of Output Task and Learning of Target Form

Directory of Open Access Journals (Sweden)

Mohammad Reza Hasannejad

2010-05-01

Full Text Available The effect of error feedback on the accuracy of output task types such as editing task, text reconstruction task, picture cued writing task, and dictogloss task, has not been clearly explored. Following arguments concerning that the combination of both corrective feedback and output makes it difficult to determine whether their effects were in combination or alone, the purpose of the present study is to document the role of teachers’ feedback in improving the accuracy of linguistic form in output tasks and in acquiring target form. To this end, this study compared three groups of Iranian intermediate learners (N= 93, one with direct grammar feedback, the other one with indirect grammar feedback and the last one with no grammar feedback. In terms of the target form uptake from first to subsequent text reconstruction tasks, the analysis of the data obtained within ten treatment sessions indicated that the participants, who received written corrective feedback compared to those who did not, progressed significantly from the first to the subsequent output tasks. In terms of learning, the learners who had the opportunities for receiving feedback performed significantly better than those in non- feedback condition on the production and recognition post- tests although explicit feedback rather than implicit feedback led to greater learning of target form on the production test, but no significant differences were found in relative efficacy of the two written corrective feedback types as far as the result of the recognition test was concerned.

Fairness-Based Tasks for Assessing Children’s Perceptions of Food Quantities and Associations with Portion Selection

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Aurore Ferrage

2018-04-01

Full Text Available It is critical to develop ecologically valid experimental methods to assess consumers’ food-related behaviors. Ad libitum approaches are often used but may not be appropriate for studies with children or with products that are not typically consumed until the individual feels full. The current study presents novel methods to assess children’s size perception and portion preference for gummy candies. In the first study, 62 children (30 boys, 32 girls aged 6 to 9 years completed two matching tasks: one using pictures on a computer screen, and a similar task where the products were physically manipulated. Results of the two matching tasks were correlated, demonstrating that a computer-based approach could be used to predict the factors influencing children’s perception of food amount: the number, size, and shape of pieces. In the second study, a portioning measure was developed to investigate whether the factors identified in the matching tasks were confirmed in a task that more closely represented portion selection in the real world. The effects observed in the matching tasks could not be replicated in the portioning task. The size of each item had no significant impact on the portion selection, suggesting that it may be possible to reduce the size of pieces in snacks where multiple pieces are typically consumed without negatively impacting perceived quantity in children, thus offering a promising strategy to nudge children toward choosing smaller portions.

THE TASK-BASED APPROACH IN LANGUAGE TEACHING

Directory of Open Access Journals (Sweden)

Aquilino Sánchez

2004-06-01

Full Text Available The Task-Based Approach (TBA has gained popularity in the field of language teaching since the last decade of the 20th Century and significant scholars have joined the discussion and increased the amount of analytical studies on the issue. Nevertheless experimental research is poor, and the tendency of some of the scholars is nowadays shifting towards a more tempered and moderate stand on their claims. Reasons for that are various: the difficulty in the implementation of the method in the classroom, the difficulty in elaborating materials following the TBA and the scarcity of task-based manuals count as important and perhaps decisive arguments. But there are also theoretical implications in the TBA which do not seem to be fully convincing or may lack sound foundations. In this paper I will attempt to describe the TBA criticaIly, pointing out what I consider positive in this approach, and underlining the inadequacy of some assumptions and conclusions. The design of a new TBA model is not the goal of this study. But the conclusions suggest that tasks may contribute to the production of a more refined and complete foreign language syllabus, helping to motivate the students and focus the attention of teachers and learners on meaning and communicative language use.

Task-selective memory effects for successfully implemented encoding strategies.

Science.gov (United States)

Leshikar, Eric D; Duarte, Audrey; Hertzog, Christopher

2012-01-01

Previous behavioral evidence suggests that instructed strategy use benefits associative memory formation in paired associate tasks. Two such effective encoding strategies--visual imagery and sentence generation--facilitate memory through the production of different types of mediators (e.g., mental images and sentences). Neuroimaging evidence suggests that regions of the brain support memory reflecting the mental operations engaged at the time of study. That work, however, has not taken into account self-reported encoding task success (i.e., whether participants successfully generated a mediator). It is unknown, therefore, whether task-selective memory effects specific to each strategy might be found when encoding strategies are successfully implemented. In this experiment, participants studied pairs of abstract nouns under either visual imagery or sentence generation encoding instructions. At the time of study, participants reported their success at generating a mediator. Outside of the scanner, participants further reported the quality of the generated mediator (e.g., images, sentences) for each word pair. We observed task-selective memory effects for visual imagery in the left middle occipital gyrus, the left precuneus, and the lingual gyrus. No such task-selective effects were observed for sentence generation. Intriguingly, activity at the time of study in the left precuneus was modulated by the self-reported quality (vividness) of the generated mental images with greater activity for trials given higher ratings of quality. These data suggest that regions of the brain support memory in accord with the encoding operations engaged at the time of study.

Modular Product Families and Assembly Systems

DEFF Research Database (Denmark)

Thyssen, Jesper

2005-01-01

This research centres on assembly systems designed for utilizing product modularization. Altogether, the task for companies has become an issue of managing the overall trade-off between the external market’s desire for variety and the internal efficiency and effectiveness. Product modularization...... a number of theoretical and managerial implications are identified. From a management point of view, the most im-portant finding is that modularization needs to be configured for the two competitive situations, i.e. 1) the volume flexible configuration focusing on generational product variety and 2......) the mix flexible con-figuration focusing on the simultaneous product variety. These two views are in particular different in respect to the understanding of product modularization. All in all, modularization needs to be, and can be, configured in regard to the specific task, which is believed constituting...

Effective task communication : the role of task information and the interpersonal teacher-student relationship.

NARCIS (Netherlands)

Broekkamp, H.; Dijk, van E.; Brekelmans, J.M.G.; Mainhard, T.; Brok, den P.J.

2009-01-01

Students who perceive assigned academic tasks as more clear perform better on these tasks. Moreover, it has been shown that "task clarity" (as experienced by students) varies across teachers. Apparently, some teachers are more effective than other teachers in communicating tasks. There is, however,

Localization Accuracy of Distributed Inverse Solutions for Electric and Magnetic Source Imaging of Interictal Epileptic Discharges in Patients with Focal Epilepsy.

Science.gov (United States)

Heers, Marcel; Chowdhury, Rasheda A; Hedrich, Tanguy; Dubeau, François; Hall, Jeffery A; Lina, Jean-Marc; Grova, Christophe; Kobayashi, Eliane

2016-01-01

Distributed inverse solutions aim to realistically reconstruct the origin of interictal epileptic discharges (IEDs) from noninvasively recorded electroencephalography (EEG) and magnetoencephalography (MEG) signals. Our aim was to compare the performance of different distributed inverse solutions in localizing IEDs: coherent maximum entropy on the mean (cMEM), hierarchical Bayesian implementations of independent identically distributed sources (IID, minimum norm prior) and spatially coherent sources (COH, spatial smoothness prior). Source maxima (i.e., the vertex with the maximum source amplitude) of IEDs in 14 EEG and 19 MEG studies from 15 patients with focal epilepsy were analyzed. We visually compared their concordance with intracranial EEG (iEEG) based on 17 cortical regions of interest and their spatial dispersion around source maxima. Magnetic source imaging (MSI) maxima from cMEM were most often confirmed by iEEG (cMEM: 14/19, COH: 9/19, IID: 8/19 studies). COH electric source imaging (ESI) maxima co-localized best with iEEG (cMEM: 8/14, COH: 11/14, IID: 10/14 studies). In addition, cMEM was less spatially spread than COH and IID for ESI and MSI (p < 0.001 Bonferroni-corrected post hoc t test). Highest positive predictive values for cortical regions with IEDs in iEEG could be obtained with cMEM for MSI and with COH for ESI. Additional realistic EEG/MEG simulations confirmed our findings. Accurate spatially extended sources, as found in cMEM (ESI and MSI) and COH (ESI) are desirable for source imaging of IEDs because this might influence surgical decision. Our simulations suggest that COH and IID overestimate the spatial extent of the generators compared to cMEM.

Method for alignment of product and production concepts

DEFF Research Database (Denmark)

Pedersen, Rasmus; Kvist, Morten; Mortensen, Niels Henrik

2005-01-01

The right use of modular product architectures can help companies provide a great variety of customized products at a competitive price level, by reuse of knowledge, components, processes and utilization of economies of scale in many of the activities that are necessary to provide products...... for customers. Modular product architectures often serve as a basis for several products often referred to as product families. One or more product families may constitute a substantial amount of the total product portfolio of a company, and it is, therefore, of the greatest importance that concepts...... and solutions are evaluated thoroughly throughout the design phases because any design fault is likely to propagate to a large part of the business. Developing modular product architectures is therefore also the task of ensuring a fit between the products that can be made on the basis of the architecture...

Testosterone: from initiating change to modulating social organisation in domestic fowl ( Gallus gallus domesticus)

Science.gov (United States)

Kent, John P.; Murphy, Kenneth J.; Bannon, Finian J.; Hynes, Niamh M.; Hayden, Thomas J.

2009-07-01

Testosterone (T) concentrations in many species are sensitive to seasonal changes and to changes in social conditions. However, the effect of the natural or endogenous T increase in the juvenile on their social behaviour is not well understood. In this study, T and behaviour were measured from the pro-social juvenile to the adult stage in semi-feral domestic fowl. During the pro-social phase T levels and the distance chicks maintained between each other, i.e. inter-individual distance (IID) were low. Then, as T increased, a corresponding increase in IID occurred and continued in males until dispersal to individual adult male territories. In the new and initially stable adult social structure, T declined and IID remained high, indicating a new behavioural mechanism was in place. Males first mated as T levels were declining. They were then challenged; then T increased, and then IID increased again. Adult male T levels fluctuate, being low or declining in a socially stable environment and increasing following a challenge, suggesting a regulatory or modulating role for T. The results are consistent with T having an endogenous role: in the juvenile, driving behavioural change towards adulthood, and in adulthood, a modulating role regulating social organisation.

Implicit and Explicit Knowledge Both Improve Dual Task Performance in a Continuous Pursuit Tracking Task.

Science.gov (United States)

Ewolds, Harald E; Bröker, Laura; de Oliveira, Rita F; Raab, Markus; Künzell, Stefan

2017-01-01

The goal of this study was to investigate the effect of predictability on dual-task performance in a continuous tracking task. Participants practiced either informed (explicit group) or uninformed (implicit group) about a repeated segment in the curves they had to track. In Experiment 1 participants practices the tracking task only, dual-task performance was assessed after by combining the tracking task with an auditory reaction time task. Results showed both groups learned equally well and tracking performance on a predictable segment in the dual-task condition was better than on random segments. However, reaction times did not benefit from a predictable tracking segment. To investigate the effect of learning under dual-task situation participants in Experiment 2 practiced the tracking task while simultaneously performing the auditory reaction time task. No learning of the repeated segment could be demonstrated for either group during the training blocks, in contrast to the test-block and retention test, where participants performed better on the repeated segment in both dual-task and single-task conditions. Only the explicit group improved from test-block to retention test. As in Experiment 1, reaction times while tracking a predictable segment were no better than reaction times while tracking a random segment. We concluded that predictability has a positive effect only on the predictable task itself possibly because of a task-shielding mechanism. For dual-task training there seems to be an initial negative effect of explicit instructions, possibly because of fatigue, but the advantage of explicit instructions was demonstrated in a retention test. This might be due to the explicit memory system informing or aiding the implicit memory system.

Task Uncertainty Can Account for Mixing and Switch Costs in Task-Switching

Science.gov (United States)

Rennie, Jaime L.

2015-01-01

Cognitive control is required in situations that involve uncertainty or change, such as when resolving conflict, selecting responses and switching tasks. Recently, it has been suggested that cognitive control can be conceptualised as a mechanism which prioritises goal-relevant information to deal with uncertainty. This hypothesis has been supported using a paradigm that requires conflict resolution. In this study, we examine whether cognitive control during task switching is also consistent with this notion. We used information theory to quantify the level of uncertainty in different trial types during a cued task-switching paradigm. We test the hypothesis that differences in uncertainty between task repeat and task switch trials can account for typical behavioural effects in task-switching. Increasing uncertainty was associated with less efficient performance (i.e., slower and less accurate), particularly on switch trials and trials that afford little opportunity for advance preparation. Interestingly, both mixing and switch costs were associated with a common episodic control process. These results support the notion that cognitive control may be conceptualised as an information processor that serves to resolve uncertainty in the environment. PMID:26107646

Structural and Functional Views of Mechatronic Products

DEFF Research Database (Denmark)

Nielsen, Kjeld; Petersen, Thomas Ditlev; Jørgensen, Kaj Asbjørn

2011-01-01

The development and subsequent production of industrial products are often complicated tasks. The complication increases with combined product as mechatronic products and is further complicated when large variety is required. Modularity is often used to achieve optimum in these complications both...

Performance Enhancements Under Dual-task Conditions

Science.gov (United States)

Kramer, A. F.; Wickens, C. D.; Donchin, E.

1984-01-01

Research on dual-task performance has been concerned with delineating the antecedent conditions which lead to dual-task decrements. Capacity models of attention, which propose that a hypothetical resource structure underlies performance, have been employed as predictive devices. These models predict that tasks which require different processing resources can be more successfully time shared than tasks which require common resources. The conditions under which such dual-task integrality can be fostered were assessed in a study in which three factors likely to influence the integrality between tasks were manipulated: inter-task redundancy, the physical proximity of tasks and the task relevant objects. Twelve subjects participated in three experimental sessions in which they performed both single and dual-tasks. The primary task was a pursuit step tracking task. The secondary tasks required the discrimination between different intensities or different spatial positions of a stimulus. The results are discussed in terms of a model of dual-task integrality.

Task-relevant cognitive and motor functions are prioritized during prolonged speed-accuracy motor task performance.

Science.gov (United States)

Solianik, Rima; Satas, Andrius; Mickeviciene, Dalia; Cekanauskaite, Agne; Valanciene, Dovile; Majauskiene, Daiva; Skurvydas, Albertas

2018-06-01

This study aimed to explore the effect of prolonged speed-accuracy motor task on the indicators of psychological, cognitive, psychomotor and motor function. Ten young men aged 21.1 ± 1.0 years performed a fast- and accurate-reaching movement task and a control task. Both tasks were performed for 2 h. Despite decreased motivation, and increased perception of effort as well as subjective feeling of fatigue, speed-accuracy motor task performance improved during the whole period of task execution. After the motor task, the increased working memory function and prefrontal cortex oxygenation at rest and during conflict detection, and the decreased efficiency of incorrect response inhibition and visuomotor tracking were observed. The speed-accuracy motor task increased the amplitude of motor-evoked potentials, while grip strength was not affected. These findings demonstrate that to sustain the performance of 2-h speed-accuracy task under conditions of self-reported fatigue, task-relevant functions are maintained or even improved, whereas less critical functions are impaired.

How Offshoring Elicits Reconfiguration of the Service Production System

DEFF Research Database (Denmark)

Brandl, Kristin; Mol, Michael J.; Petersen, Bent

Service production systems can be seen as a structure consisting of task execution, resources executing tasks and the service output received by the client. Offshoring acts as an exogenous shock to such a service production system. Drawing on practice theory and applying a multiple case methodology...... of the impact of offshoring and to practice theory....

Planning oral narrative tasks: optimizing strategic planning condition through strategy instruction

Directory of Open Access Journals (Sweden)

André Luís Specht

2017-06-01

Full Text Available This article presents the results of a master thesis, which aimed at investigating the impact of strategic planning instruction on the speech performance of 6 L2 Brazilian learners. The participants, Letras-Inglês students, performed three now-and-there picture-cued narrative tasks under three different conditions: (1 no planning, (2 planning before instruction, and (3 planning after instruction. In addition, the participants filled in post-task questionnaires after the performance of each task, aiming at understanding their opinion on the conditions and tasks. Quantitative and qualitative analyses were conducted in order to examine participants’ oral production and perception, respectively. In general, there was no statistical evidence supporting the impact of instruction on participants’ oral planned performance; however, some statistical results approached significance, which may suggest some positive effects. Qualitative analyses provided positive evidence of the impact of strategic planning instruction on participant perception and their use of strategies during planning time. Moreover, the results of this study can contribute to the fields of Second Language Acquisition and Language Pegadogy.

Task assignment and coaching

OpenAIRE

Dominguez-Martinez, S.

2009-01-01

An important task of a manager is to motivate her subordinates. One way in which a manager can give incentives to junior employees is through the assignment of tasks. How a manager allocates tasks in an organization, provides information to the junior employees about his ability. Without coaching from a manager, the junior employee only has information about his past performance. Based on his past performance, a talented junior who has performed a difficult task sometimes decides to leave the...

Functional Task Test (FTT)

Science.gov (United States)

Bloomberg, Jacob J.; Mulavara, Ajitkumar; Peters, Brian T.; Rescheke, Millard F.; Wood, Scott; Lawrence, Emily; Koffman, Igor; Ploutz-Snyder, Lori; Spiering, Barry A.; Feeback, Daniel L.;

Anterior medial prefrontal cortex exhibits activation during task preparation but deactivation during task execution.

Directory of Open Access Journals (Sweden)

Hideya Koshino

Full Text Available BACKGROUND: The anterior prefrontal cortex (PFC exhibits activation during some cognitive tasks, including episodic memory, reasoning, attention, multitasking, task sets, decision making, mentalizing, and processing of self-referenced information. However, the medial part of anterior PFC is part of the default mode network (DMN, which shows deactivation during various goal-directed cognitive tasks compared to a resting baseline. One possible factor for this pattern is that activity in the anterior medial PFC (MPFC is affected by dynamic allocation of attentional resources depending on task demands. We investigated this possibility using an event related fMRI with a face working memory task. METHODOLOGY/PRINCIPAL FINDINGS: Sixteen students participated in a single fMRI session. They were asked to form a task set to remember the faces (Face memory condition or to ignore them (No face memory condition, then they were given 6 seconds of preparation period before the onset of the face stimuli. During this 6-second period, four single digits were presented one at a time at the center of the display, and participants were asked to add them and to remember the final answer. When participants formed a task set to remember faces, the anterior MPFC exhibited activation during a task preparation period but deactivation during a task execution period within a single trial. CONCLUSIONS/SIGNIFICANCE: The results suggest that the anterior MPFC plays a role in task set formation but is not involved in execution of the face working memory task. Therefore, when attentional resources are allocated to other brain regions during task execution, the anterior MPFC shows deactivation. The results suggest that activation and deactivation in the anterior MPFC are affected by dynamic allocation of processing resources across different phases of processing.

Language Learners' Writing Task Representation and Its Effect on Written Performance in an EFL Context.

Science.gov (United States)

Zarei, Gholam Reza; Pourghasemian, Hossein; Jalali, Hassan

2017-06-01

The present study attempts to give an account of how students represent writing task in an EAP course. Further, the study is intended to discover if learners' mental representation of writing would contribute to their written performance. During a 16-week term, students were instructed to practice writing as a problem solving activity. At almost the end of the term, they were prompted to write on what they thought writing task was like and also an essay on an argumentative topic. The results revealed that students could conceptualize the instructed recursive model of writing as a process-based, multi-dimensional and integrated activity inducing self-direction and organization while holding in low regard the product view of writing. The findings also demonstrated that task representation was related to the students' writing performance, with process oriented students significantly outperforming the product-oriented ones. Also, it was found that task representation components (ideational, linguistic, textual, interpersonal) had a significant relationship with the written performance ([Formula: see text]; Sig.: 0.006). The study can have both theoretical and practical implications with regard to the factors involving the students' writing internal processes and their effects on written performance.

Prospective memory in young and older adults: the effects of task importance and ongoing task load.

Science.gov (United States)

Smith, Rebekah E; Hunt, R Reed

2014-01-01

Remembering to perform an action in the future, called prospective memory, often shows age-related differences in favor of young adults when tested in the laboratory. Recently Smith, Horn, and Bayen (2012; Aging, Neuropsychology, and Cognition, 19, 495) embedded a PM task in an ongoing color-matching task and manipulated the difficulty of the ongoing task by varying the number of colors on each trial of the task. Smith et al. found that age-related differences in PM performance (lower PM performance for older adults relative to young adults) persisted even when older adults could perform the ongoing task as well or better than the young adults. The current study investigates a possible explanation for the pattern of results reported by Smith et al. by including a manipulation of task emphasis: for half of the participants the prospective memory task was emphasize, while for the other half the ongoing color-matching task was emphasized. Older adults performed a 4-color version of the ongoing color-matching task, while young adults completed either the 4-color or a more difficult 6-color version of the ongoing task. Older adults failed to perform as well as the young adults on the prospective memory task regardless of task emphasis, even when older adults were performing as well or better than the young adults on the ongoing color-matching task. The current results indicate that the lack of an effect of ongoing task load on prospective memory task performance is not due to a perception that one or the other task is more important than the other.

Increased cognitive control after task conflict? Investigating the N-3 effect in task switching.

Science.gov (United States)

Schuch, Stefanie; Grange, James A

2018-05-25

Task inhibition is considered to facilitate switching to a new task and is assumed to decay slowly over time. Hence, more persisting inhibition needs to be overcome when returning to a task after one intermediary trial (ABA task sequence) than when returning after two or more intermediary trials (CBA task sequence). Schuch and Grange (J Exp Psychol Learn Mem Cogn 41:760-767, 2015) put forward the hypothesis that there is higher task conflict in ABA than CBA sequences, leading to increased cognitive control in the subsequent trial. They provided evidence that performance is better in trials following ABA than following CBA task sequences. Here, this effect of the previous task sequence ("N-3 effect") is further investigated by varying the cue-stimulus interval (CSI), allowing for short (100 ms) or long (900 ms) preparation time for the upcoming task. If increased cognitive control after ABA involves a better preparation for the upcoming task, the N-3 effect should be larger with long than short CSI. The results clearly show that this is not the case. In Experiment 1, the N-3 effect was smaller with long than short CSI; in Experiment 2, the N-3 effect was not affected by CSI. Diffusion model analysis confirmed previous results in the literature (regarding the effect of CSI and of the ABA-CBA difference); however, the N-3 effect was not unequivocally associated with any of the diffusion model parameters. In exploratory analysis, we also tested the alternative hypothesis that the N-3 effect involves more effective task shielding, which would be reflected in reduced congruency effects in trials following ABA, relative to trials following CBA; congruency effects did not differ between these conditions. Taken together, we can rule out two potential explanations of the N-3 effect: Neither is this effect due to enhanced task preparation, nor to more effective task shielding.

Bit by bit or all at once? Splitting up the inquiry task to promote children’s scientific reasoning

NARCIS (Netherlands)

Lazonder, Adrianus W.; Kamp, Ellen

2012-01-01

This study examined whether and why assigning children to a segmented inquiry task makes their investigations more productive. Sixty-one upper elementary-school pupils engaged in a simulation-based inquiry assignment either received a multivariable inquiry task (n = 21), a segmented version of this

Task assignment and coaching

NARCIS (Netherlands)

Dominguez-Martinez, S.

2009-01-01

An important task of a manager is to motivate her subordinates. One way in which a manager can give incentives to junior employees is through the assignment of tasks. How a manager allocates tasks in an organization, provides information to the junior employees about his ability. Without coaching

Blink activity and task difficulty.

Science.gov (United States)

Tanaka, Y; Yamaoka, K

1993-08-01

This study investigated the relationship between task difficulty and blink activity, which includes blink rate, blink amplitude, and blink duration. Two kinds of tasks established two levels of difficulty. In Exp. 1, a mental arithmetic task was used to examine the relationship. Analysis showed that blink rate for a difficult task was significantly higher than that for an easier one. In Exp. 2, a letter-search task (hiragana Japanese alphabet) was used while the other conditions were the same as those in Exp. 1; however, the results of this experiment were not influenced by the difficulty of the task. As results indicate that blink rate is related to not only difficulty but also the nature of the task, the nature of the task is probably dependent on a mechanism in information processing. The results for blink amplitude and blink duration showed no systematic change during either experiment.

Task Force on Energy Systems for Forward/Remote Operating Bases

Science.gov (United States)

2016-08-01

nuclear power energy systems ......................................................... 30 7.2.1 Radioisotope thermoelectric generators...issue, the Task Force found efforts to provide the most efficient methods for power production at the prime-contract level have been hampered by...management. Engineer Prime Power Operations21 describes theater level power infrastructure and inter-service responsibilities and, although dated from

Children's Choice Strategies: The Effects of Age and Task Demands

Science.gov (United States)

Bereby-Meyer, Yoella; Assor, Avi; Katz, Idit

2004-01-01

Two experiments examined the effect of age and cognitive demands on children's choice strategies. Children aged 8-9 and 12-13 years were asked to choose among either two or four products that differed in several attributes of varying importance to them. Choice tasks were designed to differentiate between the lexicographic and the equal-weighting…

Task uncertainty can account for mixing and switch costs in task-switching.

Directory of Open Access Journals (Sweden)

Patrick S Cooper

Full Text Available Cognitive control is required in situations that involve uncertainty or change, such as when resolving conflict, selecting responses and switching tasks. Recently, it has been suggested that cognitive control can be conceptualised as a mechanism which prioritises goal-relevant information to deal with uncertainty. This hypothesis has been supported using a paradigm that requires conflict resolution. In this study, we examine whether cognitive control during task switching is also consistent with this notion. We used information theory to quantify the level of uncertainty in different trial types during a cued task-switching paradigm. We test the hypothesis that differences in uncertainty between task repeat and task switch trials can account for typical behavioural effects in task-switching. Increasing uncertainty was associated with less efficient performance (i.e., slower and less accurate, particularly on switch trials and trials that afford little opportunity for advance preparation. Interestingly, both mixing and switch costs were associated with a common episodic control process. These results support the notion that cognitive control may be conceptualised as an information processor that serves to resolve uncertainty in the environment.

Preferential processing of task-irrelevant beloved-related information and task performance: Two event-related potential studies.

Science.gov (United States)

Langeslag, Sandra J E; van Strien, Jan W

2017-09-18

People who are in love have better attention for beloved-related information, but report having trouble focusing on other tasks, such as (home)work. So, romantic love can both improve and hurt cognition. Emotional information is preferentially processed, which improves task performance when the information is task-relevant, but hurts task performance when it is task-irrelevant. Because beloved-related information is highly emotional, the effects of romantic love on cognition may resemble these effects of emotion on cognition. We examined whether beloved-related information is preferentially processed even when it is task-irrelevant and whether this hurts task performance. In two event-related potential studies, participants who had recently fallen in love performed a visuospatial short-term memory task. Task-irrelevant beloved, friend, and stranger faces were presented during maintenance (Study 1), or encoding (Study 2). The Early Posterior Negativity (EPN) reflecting early automatic attentional capturing and the Late Positive Potential (LPP) reflecting sustained motivated attention were largest for beloved pictures. Thus, beloved pictures are preferentially processed even when they are task-irrelevant. Task performance and reaction times did not differ between beloved, friend, and stranger conditions. Nevertheless, self-reported obsessive thinking about the beloved tended to correlate negatively with task performance, and positively with reaction times, across conditions. So, although task-irrelevant beloved-related information does not impact task performance, more obsessive thinking about the beloved might relate to poorer and slower overall task performance. More research is needed to clarify why people experience trouble focusing on beloved-unrelated tasks and how this negative effect of love on cognition could be reduced. Copyright © 2017 Elsevier Ltd. All rights reserved.

Word position and stress effects in consonant cluster perception and production.

Science.gov (United States)

Cilibrasi, Luca; Stojanovik, Vesna; Riddell, Patricia

2015-02-01

The aim of the present study was to investigate whether the saliency effect for word beginnings reported in children with dyslexia (Marshall & Van der Lely, 2009) can be found also in typically developing children. Thirty-four typically developing Italian children aged 8-10 years completed two specifically designed tasks: a production task and a perception task. Both tasks used nonwords containing clusters consisting of plosive plus liquid (e.g. pl). Clusters could be either in a stressed or in an unstressed syllable and could be either in initial position (first syllable) or in medial position (second syllable). In the production task, children were asked to repeat the nonwords. In the perception task, the children were asked to discriminate between two nonwords differing in one phoneme belonging to a cluster by reporting whether two repetitions were the same or different. Results from the production task showed that children are more accurate in repeating stressed than unstressed syllables, but there was no difference with respect to position of the cluster. Results from the perception task showed that children performed more accurately when discriminating word initial contrasts than when discriminating word medial contrasts, especially if the cluster was unstressed. Implications of this finding for clinical assessments are discussed. Copyright © 2015 John Wiley & Sons, Ltd.

BIOSIMILARS IN RHEUMATOLOGY

Directory of Open Access Journals (Sweden)

E. L. Nasonov

2016-01-01

Full Text Available One of the most striking achievements in the pharmacotherapy of rheumatoid arthritis (RA and other human immunoinflammatory diseases (IIDs late in the 20th century is associated with the design of a fundamentally new group of medications that received the name biological agents (BAs. However, the introduction of innovative BAs into clinical practice not only could enhance the efficiency of therapy and improve prognosis in patients with the most severe forms of IIDs, but has also led to a dramatic increase in the cost of treatment. Progress in the design of biosimilars is related to many factors, including expiry of the term of patents for many brand-name BAs, such as infliximab, adalimumab, etanercept, and rituximab. Over the last 5 years, a large number of biosimilars have been designed and their design is being continued. The European Medicines Agency, the World Health Organization, and the U.S. Food and Drug Administration have developed a regulatory framework and general requirements for the manufacture and characteristics of biosimilars. Federal Law No. 429-FZ «On Amendments to the Federal Law "On Circulation of Medicines"» dated December 22, 2014 defines a biosimilar drug as a biological medicine product that is similar to the parameters of quality, efficiency, and safety with the reference biologic drug in the same formulation, and the same route of administration. The review presents an update on the requirements for biosimilars used to treat IIDs, their interchangeability and promises in further clinical application. Particular emphasis is laid on the chimeric monoclonal antibodies to tumor necrosis factor-α infliximab biosimilar Flammegis (Egis Pharmaceuticals, Hungary, that has been registered in Russia for the treatment of RA, ankylosing spondylitis and other IIDs, as well as the chimeric monoclonal antibodies to B-lymphocytes rituximab biosimilar Acellbia in a phase III clinical trial that is in the closing

Task-selective memory effects for successfully implemented encoding strategies.

Directory of Open Access Journals (Sweden)

Eric D Leshikar

Full Text Available Previous behavioral evidence suggests that instructed strategy use benefits associative memory formation in paired associate tasks. Two such effective encoding strategies--visual imagery and sentence generation--facilitate memory through the production of different types of mediators (e.g., mental images and sentences. Neuroimaging evidence suggests that regions of the brain support memory reflecting the mental operations engaged at the time of study. That work, however, has not taken into account self-reported encoding task success (i.e., whether participants successfully generated a mediator. It is unknown, therefore, whether task-selective memory effects specific to each strategy might be found when encoding strategies are successfully implemented. In this experiment, participants studied pairs of abstract nouns under either visual imagery or sentence generation encoding instructions. At the time of study, participants reported their success at generating a mediator. Outside of the scanner, participants further reported the quality of the generated mediator (e.g., images, sentences for each word pair. We observed task-selective memory effects for visual imagery in the left middle occipital gyrus, the left precuneus, and the lingual gyrus. No such task-selective effects were observed for sentence generation. Intriguingly, activity at the time of study in the left precuneus was modulated by the self-reported quality (vividness of the generated mental images with greater activity for trials given higher ratings of quality. These data suggest that regions of the brain support memory in accord with the encoding operations engaged at the time of study.

Task leaders reports

International Nuclear Information System (INIS)

Loriaux, E.F.; Jehee, J.N.T.

1995-01-01

Report on CRP-OSS Task 4.1.1. ''Survey of existing documentation relevant to this programme's goals'' and report on CRP-OSS Task 4.1.2. ''Survey of existing Operator Support Systems and the experience with them'' are presented. 2 tabs

Productivity associated with visual status of computer users.

Science.gov (United States)

Daum, Kent M; Clore, Katherine A; Simms, Suzanne S; Vesely, Jon W; Wilczek, Dawn D; Spittle, Brian M; Good, Greg W

2004-01-01

The aim of this project is to examine the potential connection between the astigmatic refractive corrections of subjects using computers and their productivity and comfort. We hypothesize that improving the visual status of subjects using computers results in greater productivity, as well as improved visual comfort. Inclusion criteria required subjects 19 to 30 years of age with complete vision examinations before being enrolled. Using a double-masked, placebo-controlled, randomized design, subjects completed three experimental tasks calculated to assess the effects of refractive error on productivity (time to completion and the number of errors) at a computer. The tasks resembled those commonly undertaken by computer users and involved visual search tasks of: (1) counties and populations; (2) nonsense word search; and (3) a modified text-editing task. Estimates of productivity for time to completion varied from a minimum of 2.5% upwards to 28.7% with 2 D cylinder miscorrection. Assuming a conservative estimate of an overall 2.5% increase in productivity with appropriate astigmatic refractive correction, our data suggest a favorable cost-benefit ratio of at least 2.3 for the visual correction of an employee (total cost 268 dollars) with a salary of 25,000 dollars per year. We conclude that astigmatic refractive error affected both productivity and visual comfort under the conditions of this experiment. These data also suggest a favorable cost-benefit ratio for employers who provide computer-specific eyewear to their employees.

Metacognitive deficits in categorization tasks in a population with impaired inner speech.

Science.gov (United States)

Langland-Hassan, Peter; Gauker, Christopher; Richardson, Michael J; Dietz, Aimee; Faries, Frank R

2017-11-01

This study examines the relation of language use to a person's ability to perform categorization tasks and to assess their own abilities in those categorization tasks. A silent rhyming task was used to confirm that a group of people with post-stroke aphasia (PWA) had corresponding covert language production (or "inner speech") impairments. The performance of the PWA was then compared to that of age- and education-matched healthy controls on three kinds of categorization tasks and on metacognitive self-assessments of their performance on those tasks. The PWA showed no deficits in their ability to categorize objects for any of the three trial types (visual, thematic, and categorial). However, on the categorial trials, their metacognitive assessments of whether they had categorized correctly were less reliable than those of the control group. The categorial trials were distinguished from the others by the fact that the categorization could not be based on some immediately perceptible feature or on the objects' being found together in a type of scenario or setting. This result offers preliminary evidence for a link between covert language use and a specific form of metacognition. Copyright © 2017 Elsevier B.V. All rights reserved.

An evaluation of performance by older persons on a simulated telecommuting task.

Science.gov (United States)

Sharit, Joseph; Czaja, Sara J; Hernandez, Mario; Yang, Yulong; Perdomo, Dolores; Lewis, John E; Lee, Chin Chin; Nair, Sankaran

2004-11-01

Telecommuting work represents a strategy for managing the growing number of older people in the workforce. This study involved a simulated customer service telecommuting task that used e-mail to answer customer queries about media-related products and company policies. Participants included 27 "younger" older adults (50-65 years) and 25 "older" older adults (66-80 years). The participants performed the task for two 2-hr sessions a day over 4 consecutive days. Although both age groups showed significant improvement across sessions on many of the performance criteria, in general the improvements were more marked for the older age-group participants. However, the participants from both age groups had difficulty meeting some of the task performance requirements. These results are discussed in terms of training strategies for older workers.

Human factors evaluation of remote afterloading brachytherapy. Volume 2, Function and task analysis

Energy Technology Data Exchange (ETDEWEB)

Callan, J.R.; Gwynne, J.W. III; Kelly, T.T.; Muckler, F.A. [Pacific Science and Engineering Group, San Diego, CA (United States); Saunders, W.M.; Lepage, R.P.; Chin, E. [University of California San Diego Medical Center, CA (United States). Div. of Radiation Oncology; Schoenfeld, I.; Serig, D.I. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology

1995-05-01

A human factors project on the use of nuclear by-product material to treat cancer using remotely operated afterloaders was undertaken by the Nuclear Regulatory Commission. The purpose of the project was to identify factors that contribute to human error in the system for remote afterloading brachytherapy (RAB). This report documents the findings from the first phase of the project, which involved an extensive function and task analysis of RAB. This analysis identified the functions and tasks in RAB, made preliminary estimates of the likelihood of human error in each task, and determined the skills needed to perform each RAB task. The findings of the function and task analysis served as the foundation for the remainder of the project, which evaluated four major aspects of the RAB system linked to human error: human-system interfaces; procedures and practices; training and qualifications of RAB staff; and organizational practices and policies. At its completion, the project identified and prioritized areas for recommended NRC and industry attention based on all of the evaluations and analyses.

Human factors evaluation of remote afterloading brachytherapy. Volume 2, Function and task analysis

International Nuclear Information System (INIS)

Callan, J.R.; Gwynne, J.W. III; Kelly, T.T.; Muckler, F.A.; Saunders, W.M.; Lepage, R.P.; Chin, E.; Schoenfeld, I.; Serig, D.I.

1995-05-01

A human factors project on the use of nuclear by-product material to treat cancer using remotely operated afterloaders was undertaken by the Nuclear Regulatory Commission. The purpose of the project was to identify factors that contribute to human error in the system for remote afterloading brachytherapy (RAB). This report documents the findings from the first phase of the project, which involved an extensive function and task analysis of RAB. This analysis identified the functions and tasks in RAB, made preliminary estimates of the likelihood of human error in each task, and determined the skills needed to perform each RAB task. The findings of the function and task analysis served as the foundation for the remainder of the project, which evaluated four major aspects of the RAB system linked to human error: human-system interfaces; procedures and practices; training and qualifications of RAB staff; and organizational practices and policies. At its completion, the project identified and prioritized areas for recommended NRC and industry attention based on all of the evaluations and analyses

Reward, Task Motivation, Creativity and Teaching: Towards a Cross-Cultural Examination

Science.gov (United States)

Hennessey, Beth A.

2015-01-01

Background: Extrinsic incentives and constraints to learning, such as the promise of a reward or the expectation of an evaluation, have long been used by educators to motivate students. Previous research has consistently found that expected reward consistently undermines intrinsic task motivation and creativity of products and performance in…

Distraction during learning with hypermedia: Difficult tasks help to keep task goals on track

Directory of Open Access Journals (Sweden)

Katharina eScheiter

2014-03-01

Full Text Available In educational hypermedia environments, students are often confronted with potential sources of distraction arising from additional information that, albeit interesting, is unrelated to their current task goal. The paper investigates the conditions under which distraction occurs and hampers performance. Based on theories of volitional action control it was hypothesized that interesting information, especially if related to a pending goal, would interfere with task performance only when working on easy, but not on difficult tasks. In Experiment 1, 66 students learned about probability theory using worked examples and solved corresponding test problems, whose task difficulty was manipulated. As a second factor, the presence of interesting information unrelated to the primary task was varied. Results showed that students solved more easy than difficult probability problems correctly. However, the presence of interesting, but task-irrelevant information did not interfere with performance. In Experiment 2, 68 students again engaged in example-based learning and problem solving in the presence of task-irrelevant information. Problem-solving difficulty was varied as a first factor. Additionally, the presence of a pending goal related to the task-irrelevant information was manipulated. As expected, problem-solving performance declined when a pending goal was present during working on easy problems, whereas no interference was observed for difficult problems. Moreover, the presence of a pending goal reduced the time on task-relevant information and increased the time on task-irrelevant information while working on easy tasks. However, as revealed by mediation analyses these changes in overt information processing behavior did not explain the decline in problem-solving performance. As an alternative explanation it is suggested that goal conflicts resulting from pending goals claim cognitive resources, which are then no longer available for learning and

Single-Task and Dual-Task Gait Among Collegiate Athletes of Different Sport Classifications: Implications for Concussion Management.

Science.gov (United States)

Howell, David R; Oldham, Jessie R; DiFabio, Melissa; Vallabhajosula, Srikant; Hall, Eric E; Ketcham, Caroline J; Meehan, William P; Buckley, Thomas A

2017-02-01

Gait impairments have been documented following sport-related concussion. Whether preexisting gait pattern differences exist among athletes who participate in different sport classifications, however, remains unclear. Dual-task gait examinations probe the simultaneous performance of everyday tasks (ie, walking and thinking), and can quantify gait performance using inertial sensors. The purpose of this study was to compare the single-task and dual-task gait performance of collision/contact and noncontact athletes. A group of collegiate athletes (n = 265) were tested before their season at 3 institutions (mean age= 19.1 ± 1.1 years). All participants stood still (single-task standing) and walked while simultaneously completing a cognitive test (dual-task gait), and completed walking trials without the cognitive test (single-task gait). Spatial-temporal gait parameters were compared between collision/contact and noncontact athletes using MANCOVAs; cognitive task performance was compared using ANCOVAs. No significant single-task or dual-task gait differences were found between collision/contact and noncontact athletes. Noncontact athletes demonstrated higher cognitive task accuracy during single-task standing (P = .001) and dual-task gait conditions (P = .02) than collision/contact athletes. These data demonstrate the utility of a dual-task gait assessment outside of a laboratory and suggest that preinjury cognitive task performance during dual-tasks may differ between athletes of different sport classifications.

Development of a hospital mobile platform for logistics tasks

Directory of Open Access Journals (Sweden)

Carlos Antonio Acosta Calderon

2015-04-01

Full Text Available Healthcare services heavily rely on healthcare staff and subsequently, there is the need to improve healthcare staff׳s workflow. The deployment of an automated mobile base will help enhance the productivity of logistics tasks in the hospital, like collection and delivery. By improving such logistic tasks healthcare personal is able to focus on other tasks to serve the community better. Currently there are commercial solutions to deal with these logistic tasks, where a mobile base is able to move from one place to another in a structured environment like a hospital. In this paper, we present our approach to develop a cost effective mobile base to be used for delivery in healthcare amenities. The proposed approach is able to navigate among stations in the hospital by first creating a map of the floor and then indicating the location of these stations. This reduces the additional cost of drawing lines on the floor or to put laser markers and many of the commercial solutions required. In addition, the proposed solution is able to navigate while being safe for the people moving around and to the transported items. The paper discusses the design consideration of the system, the navigation and the battery management to ensure that the system is able to run autonomously without the need recharge often.

Extending product modeling methods for integrated product development

DEFF Research Database (Denmark)

Bonev, Martin; Wörösch, Michael; Hauksdóttir, Dagný

2013-01-01

Despite great efforts within the modeling domain, the majority of methods often address the uncommon design situation of an original product development. However, studies illustrate that development tasks are predominantly related to redesigning, improving, and extending already existing products...... and PVM methods, in a presented Product Requirement Development model some of the individual drawbacks of each method could be overcome. Based on the UML standard, the model enables the representation of complex hierarchical relationships in a generic product model. At the same time it uses matrix....... Updated design requirements have then to be made explicit and mapped against the existing product architecture. In this paper, existing methods are adapted and extended through linking updated requirements to suitable product models. By combining several established modeling techniques, such as the DSM...

The significance of Sampling Design on Inference: An Analysis of Binary Outcome Model of Children’s Schooling Using Indonesian Large Multi-stage Sampling Data

OpenAIRE

Ekki Syamsulhakim

2008-01-01

This paper aims to exercise a rather recent trend in applied microeconometrics, namely the effect of sampling design on statistical inference, especially on binary outcome model. Many theoretical research in econometrics have shown the inappropriateness of applying i.i.dassumed statistical analysis on non-i.i.d data. These research have provided proofs showing that applying the iid-assumed analysis on a non-iid observations would result in an inflated standard errors which could make the esti...

The relation between task characteristics, BI quality and task compatibility: An explorative study

DEFF Research Database (Denmark)

Gaardboe, Rikke; Jonasen, Tanja Svarre; Nyvang, Tom

2018-01-01

The purpose of this article is to investigate the relationship between task characteristics, business intelligence (BI) quality, and task compatibility. It is essential to investigate this relationship, as BI often builds up data from the organization's existing information systems, and thus......, is a supplement. In addition, there is a gap within existing research about task characteristics and BI. We conducted a survey of three companies, where 104 BI end users answered the questionnaire. Our findings reveal that BI users who experience high information quality solve difficult tasks, have a specified...

"Smart inhibition": electrophysiological evidence for the suppression of conflict-generating task rules during task switching.

Science.gov (United States)

Meiran, Nachshon; Hsieh, Shulan; Chang, Chi-Chih

2011-09-01

A major challenge for task switching is maintaining a balance between high task readiness and effectively ignoring irrelevant task rules. This calls for finely tuned inhibition that targets only the source of interference without adversely influencing other task-related representations. The authors show that irrelevant task rules generating response conflict are inhibited, causing their inefficient execution on the next trial (indicating the presence of competitor rule suppression[CRS];Meiran, Hsieh, & Dimov, Journal of Experimental Psychology: Learning, Memory and Cognition, 36, 992-1002, 2010). To determine whether CRS influences task rules, rather than target stimuli or responses, the authors focused on the processing of the task cue before the target stimulus was presented and before the response could be chosen. As was predicted, CRS was found in the event-related potentials in two time windows during task cue processing. It was also found in three time windows after target presentation. Source localization analyses suggest the involvement of the right dorsal prefrontal cortex in all five time windows.

On the content of a product idea

DEFF Research Database (Denmark)

Hansen, Claus Thorp; Andreasen, Mogens Myrup

2005-01-01

In an industrial company developing consumer products for the global marketplace, it is the management’s task to decide which product ideas shall be selected as a basis for developing new and innovative products. The company management has to allocate resources to a portfolio of product ideas...

Binding Task-Based Language Teaching and Task-Based Language Testing: A Survey into EFL Teachers and Learners' Views of Task-Based Approach

Science.gov (United States)

Panahi, Ali

2012-01-01

In most settings, task-based language teaching and testing have been dissociated from each other. That is why this study came to rethink of the learners' views towards awareness and implementation of task-based language teaching through IELTS listening tasks. To these objectives, after sketching instrumentation, the learners were divided into…

Crystallization and preliminary X-ray analysis of Ebola VP35 interferon inhibitory domain mutant proteins

International Nuclear Information System (INIS)

Leung, Daisy W.; Borek, Dominika; Farahbakhsh, Mina; Ramanan, Parameshwaran; Nix, Jay C.; Wang, Tianjiao; Prins, Kathleen C.; Otwinowski, Zbyszek; Honzatko, Richard B.; Helgeson, Luke A.; Basler, Christopher F.; Amarasinghe, Gaya K.

2010-01-01

Three mutant forms of Ebola VP35 interferon inhibitory domain were crystallized in three different space groups. VP35 is one of seven structural proteins encoded by the Ebola viral genome and mediates viral replication, nucleocapsid formation and host immune suppression. The C-terminal interferon inhibitory domain (IID) of VP35 is critical for dsRNA binding and interferon inhibition. The wild-type VP35 IID structure revealed several conserved residues that are important for dsRNA binding and interferon antagonism. Here, the expression, purification and crystallization of recombinant Zaire Ebola VP35 IID mutants R312A, K319A/R322A and K339A in space groups P6 1 22, P2 1 2 1 2 1 and P2 1 , respectively, are described. Diffraction data were collected using synchrotron sources at the Advanced Light Source and the Advanced Photon Source

A randomized prospective study of rehabilitation therapy in the treatment of radiation-induced dysphagia and trismus

Energy Technology Data Exchange (ETDEWEB)

Tang, Y.; Shen, Q.; Lu, K.; Peng, Y. [Sun Yat-sen Univ., Guangzhou (China). Dept. of Neurology; Wang, Y. [Sun Yat-sen Univ., Guangzhou (China). Dept. of Internal Medicine; Wang, Y. [Sun Yat-sen Univ., Guangzhou (China). Dept. of Neurosurgery

2011-01-15

Purpose: To evaluate the therapeutic effect of rehabilitation therapy on radiation-induced dysphagia and trismus in nasopharyngeal carcinoma (NPC) patients after radiotherapy. Patients and Methods: 43 NPC patients after radiotherapy were included. Patients were randomly assigned to either the rehabilitation group or a control group. Both groups were subjected to routine treatment, while the rehabilitation group also received rehabilitation therapy for 3 months. The severity of dysphagia was assessed using the water swallow test, while trismus was evaluated with the LENT/SOMA score and the interincisor distance (IID). The water swallow test, the LENT/SOMA score, as well as IID for both groups before and after treatment were analyzed and compared. Results: After treatment, the rehabilitation group displayed a significant improvement in swallowing function, while the control group did not. The efficacy rate (percentage of patients with excellent or effective results) of rehabilitation group was higher than that of control group (77% vs. 43%), and the difference was statistically significant ({chi}{sup 2} = 5.32, p = 0.02). IID pretreatment and posttreatment did not show much difference in the rehabilitation group, while in the control group IID significantly decreased posttreatment (1.1 {+-} 0.36 cm vs.1.8 {+-} 0.56 cm, p = 0.001). Although the mean IID in patients of both groups decreased after the 3 month follow-up, the decrease in the rehabilitation group was less than that of the control group (0.19 {+-} 0.5 cm vs. 0.69 {+-} 0.56 cm, p = 0.004). The efficacy rate of trismus in the rehabilitation group was significantly higher than that of the control group (64% vs. 28%, {chi}{sup 2} = 5.31, p = 0.02). Conclusions: Rehabilitation training can improve swallow function and slow down the progress of trismus in NPC patients following radiotherapy. (orig.)

A randomized prospective study of rehabilitation therapy in the treatment of radiation-induced dysphagia and trismus

International Nuclear Information System (INIS)

Tang, Y.; Shen, Q.; Lu, K.; Peng, Y.; Wang, Y.; Wang, Y.

2011-01-01

Purpose: To evaluate the therapeutic effect of rehabilitation therapy on radiation-induced dysphagia and trismus in nasopharyngeal carcinoma (NPC) patients after radiotherapy. Patients and Methods: 43 NPC patients after radiotherapy were included. Patients were randomly assigned to either the rehabilitation group or a control group. Both groups were subjected to routine treatment, while the rehabilitation group also received rehabilitation therapy for 3 months. The severity of dysphagia was assessed using the water swallow test, while trismus was evaluated with the LENT/SOMA score and the interincisor distance (IID). The water swallow test, the LENT/SOMA score, as well as IID for both groups before and after treatment were analyzed and compared. Results: After treatment, the rehabilitation group displayed a significant improvement in swallowing function, while the control group did not. The efficacy rate (percentage of patients with excellent or effective results) of rehabilitation group was higher than that of control group (77% vs. 43%), and the difference was statistically significant (χ 2 = 5.32, p = 0.02). IID pretreatment and posttreatment did not show much difference in the rehabilitation group, while in the control group IID significantly decreased posttreatment (1.1 ± 0.36 cm vs.1.8 ± 0.56 cm, p = 0.001). Although the mean IID in patients of both groups decreased after the 3 month follow-up, the decrease in the rehabilitation group was less than that of the control group (0.19 ± 0.5 cm vs. 0.69 ± 0.56 cm, p = 0.004). The efficacy rate of trismus in the rehabilitation group was significantly higher than that of the control group (64% vs. 28%, χ 2 = 5.31, p = 0.02). Conclusions: Rehabilitation training can improve swallow function and slow down the progress of trismus in NPC patients following radiotherapy. (orig.)

Lineage Analysis of Circulating Trypanosoma cruzi Parasites and Their Association with Clinical Forms of Chagas Disease in Bolivia

Science.gov (United States)

del Puerto, Ramona; Nishizawa, Juan Eiki; Kikuchi, Mihoko; Iihoshi, Naomi; Roca, Yelin; Avilas, Cinthia; Gianella, Alberto; Lora, Javier; Gutierrez Velarde, Freddy Udalrico; Renjel, Luis Alberto; Miura, Sachio; Higo, Hiroo; Komiya, Norihiro; Maemura, Koji; Hirayama, Kenji

2010-01-01

Background The causative agent of Chagas disease, Trypanosoma cruzi, is divided into 6 Discrete Typing Units (DTU): Tc I, IIa, IIb, IIc, IId and IIe. In order to assess the relative pathogenicities of different DTUs, blood samples from three different clinical groups of chronic Chagas disease patients (indeterminate, cardiac, megacolon) from Bolivia were analyzed for their circulating parasites lineages using minicircle kinetoplast DNA polymorphism. Methods and Findings Between 2000 and 2007, patients sent to the Centro Nacional de Enfermedades Tropicales for diagnosis of Chagas from clinics and hospitals in Santa Cruz, Bolivia, were assessed by serology, cardiology and gastro-intestinal examinations. Additionally, patients who underwent colonectomies due to Chagasic magacolon at the Hospital Universitario Japonés were also included. A total of 306 chronic Chagas patients were defined by their clinical types (81 with cardiopathy, 150 without cardiopathy, 100 with megacolon, 144 without megacolon, 164 with cardiopathy or megacolon, 73 indeterminate and 17 cases with both cardiopathy and megacolon). DNA was extracted from 10 ml of peripheral venous blood for PCR analysis. The kinetoplast minicircle DNA (kDNA) was amplified from 196 out of 306 samples (64.1%), of which 104 (53.3%) were Tc IId, 4 (2.0%) Tc I, 7 (3.6%) Tc IIb, 1 (0.5%) Tc IIe, 26 (13.3%) Tc I/IId, 1 (0.5%) Tc I/IIb/IId, 2 (1.0%) Tc IIb/d and 51 (25.9%) were unidentified. Of the 133 Tc IId samples, three different kDNA hypervariable region patterns were detected; Mn (49.6%), TPK like (48.9%) and Bug-like (1.5%). There was no significant association between Tc types and clinical manifestations of disease. Conclusions None of the identified lineages or sublineages was significantly associated with any particular clinical manifestations in the chronic Chagas patients in Bolivia. PMID:20502516

The ATLAS Production System Evolution

CERN Document Server

Borodin, Mikhail; The ATLAS collaboration

2017-01-01

The second generation of the ATLAS Production System called ProdSys2 is a distributed workload manager that runs daily hundreds of thousands of jobs, from dozens of different ATLAS-specific workflows, across more than a hundred heterogeneous sites. It achieves high utilization by combining dynamic job definition based upon many criteria, such as input and output size, memory requirements and CPU consumption, with manageable scheduling policies and by supporting different kinds of computational resources, such as GRID, clouds, supercomputers and volunteer computers. The system dynamically assigns a group of jobs (task) to a group of geographically distributed computing resources. Dynamic assignment and resource utilization is one of the major features of the system. The Production System has a sophisticated job fault recovery mechanism, which efficiently allows running multi-terabyte tasks without human intervention. We have implemented new features which allow automatic task submission and chaining of differe...

Task force on resource development and the economy

International Nuclear Information System (INIS)

Mansell, R.L.; Staples, L.B.

2011-02-01

In Alberta, the development and growth of the economy relies heavily on the resource sectors, which drive half of all employment. In 2009, the Alberta Chamber of Resources commissioned a task force, comprising groups from the 9 resource sectors in Alberta, to examine resource development and the economy. The aim of this team was to present the impact that the resource sectors had on Alberta's economy in the past, the impact it could have in the future, and to make recommendations on how to meet the full potential of resource development in the province. This reports states that considerable resources of bitumen and coal are present in Alberta and that forestry and diamonds could also play important roles in future resource development. The task force believes that the resource sectors will continue lead gross domestic product growth in Alberta and 16 recommendations for meeting the province's full potential are provided.

Assessing the Impact of (Overly Socially Desirable Brand Attributes in Choice Conjoint Tasks

Directory of Open Access Journals (Sweden)

André Carlos Martins Menck

2014-03-01

Full Text Available This research assesses the effects of corporate social responsibility on choice behavior. The construct social responsibility is highly socially desirable by definition. As a result, choice tasks in such setting may be biased by social desirability. This paper unveils a data treatment on choice conjoint tasks that sorts out the respondents who are likely to be mostly affected by social desirability. In this research a survey with choice conjoint tasks is used to evaluate interaction effects of corporate social involvement on functional attributes. Choice on four different product categories is assessed in a 215 within-subject design embedded in a 3x2x2 between-subject design. The main effects of corporate social involvement come out strong. The predicted interactions between social involvement and the functional attributes of the products seem to be affected by social desirability, leading to unclear results. The sub-samples resulting from the data manipulation, however, provide empirical support to the hypotheses on the interaction terms. This indicates the appropriateness of a model in which social involvement signals that the firm’s arguments on its products’ credence attributes are worth trusting. Nonetheless, the results with the full data prevent assertive conclusions.

Software product line engineering for consumer electronics : Keeping up with the speed of innovation

NARCIS (Netherlands)

Hartmann, Herman

2015-01-01

During the last decade consumer electronics products have changed radically. Traditionally these products were used for a few dedicated tasks, and were implemented through hardware. Nowadays, these products are used for a variety of tasks and are largely implemented through software. Furthermore

Mechanical Transformation of Task Heuristics into Operational Procedures

Science.gov (United States)

1981-04-14

Introduction A central theme of recent research in artificial intelligence is that *Intelligent task performance requires large amounts of knowledge...PLAY P1 C4] (. (LEADING (QSO)) (OR (CAN-LEAO- HEARrS (gSO)J (mEg (SUIT-OF C3) H])] C-) (FOLLOWING (QSO)) (OR [VOID (OSO) (SUIT-LED)3 [IN-SUIT C3 (SUIT...Production rules as a representation for a knowledge based consultation system. Artificial Intelligence 8:15-45, Spring, 1977. [Davis 77b] R. Davis

Cognitive demand of human sensorimotor performance during an extended space mission: a dual-task study.

Science.gov (United States)

Bock, Otmar; Weigelt, Cornelia; Bloomberg, Jacob J

2010-09-01

Two previous single-case studies found that the dual-task costs of manual tracking plus memory search increased during a space mission, and concluded that sensorimotor deficits during spaceflight may be related to cognitive overload. Since dual-task costs were insensitive to the difficulty of memory search, the authors argued that the overload may reflect stress-related problems of multitasking, rather than a scarcity of specific cognitive resources. Here we expand the available database and compare different types of concurrent task. Three subjects were repeatedly tested before, during, and after an extended mission on the International Space Station (ISS). They performed an unstable tracking task and four reaction-time tasks, both separately and concurrently. Inflight data could only be obtained during later parts of the mission. The tracking error increased from pre- to in flight by a factor of about 2, both under single- and dual-task conditions. The dual-task costs with a reaction-time task requiring rhythm production was 2.4 times higher than with a reaction-time task requiring visuo-spatial transformations, and 8 times higher than with a regular choice reaction-time task. Long-term sensorimotor deficits during spaceflight may reflect not only stress, but also a scarcity of resources related to complex motor programming; possibly those resources are tied up by sensorimotor adaptation to the space environment.

Combined analysis of job and task benzene air exposures among workers at four US refinery operations.

Science.gov (United States)

Burns, Amanda; Shin, Jennifer Mi; Unice, Ken M; Gaffney, Shannon H; Kreider, Marisa L; Gelatt, Richard H; Panko, Julie M

2017-03-01

Workplace air samples analyzed for benzene at four US refineries from 1976 to 2007 were pooled into a single dataset to characterize similarities and differences between job titles, tasks and refineries, and to provide a robust dataset for exposure reconstruction. Approximately 12,000 non-task (>180 min) personal samples associated with 50 job titles and 4000 task (job titles and task codes across all four refineries, and (5) our analysis of variance (ANOVA) of the distribution of benzene air concentrations for select jobs/tasks across all four refineries. The jobs and tasks most frequently sampled included those with highest potential contact with refinery product streams containing benzene, which reflected the targeted sampling approach utilized by the facility industrial hygienists. Task and non-task data were analyzed to identify and account for significant differences within job-area, task-job, and task-area categories. This analysis demonstrated that in general, areas with benzene containing process streams were associated with greater benzene air concentrations compared to areas with process streams containing little to no benzene. For several job titles and tasks analyzed, there was a statistically significant decrease in benzene air concentration after 1990. This study provides a job and task-focused analysis of occupational exposure to benzene during refinery operations, and it should be useful for reconstructing refinery workers' exposures to benzene over the past 30 years.

Task Repetition Effects on L1 Use in EFL Child Task-Based Interaction

Science.gov (United States)

Azkarai, Agurtzane; García Mayo, María del Pilar

2017-01-01

Research has shown that tasks provide second language (L2) learners with many opportunities to learn the L2. Task repetition has been claimed to benefit L2 learning since familiarity with procedure and/or content gives learners the chance to focus on more specific aspects of language. Most research on task repetition has focused on adult…

Effects of Multimedia Task-Based Teaching and Learning Approach on EFL Learners' Accuracy, Fluency and Complexity of Oral Production

Science.gov (United States)

Bava Harji, Madhubala; Gheitanchian, Mehrnaz

2017-01-01

Albeit Task-Based Language Teaching (TBLT) has been extensively researched, there appears to be limited studies that focus on the effects of multimedia technology (MT) enhanced TBLT approach on EFL development. A study was conducted to examine the effects of a MT imbued TBLT, i.e. Multimedia Task-Based Teaching and Learning (MMTBLT) approach on…

Information and processes underlying semantic and episodic memory across tasks, items, and individuals.

Science.gov (United States)

Cox, Gregory E; Hemmer, Pernille; Aue, William R; Criss, Amy H

2018-04-01

The development of memory theory has been constrained by a focus on isolated tasks rather than the processes and information that are common to situations in which memory is engaged. We present results from a study in which 453 participants took part in five different memory tasks: single-item recognition, associative recognition, cued recall, free recall, and lexical decision. Using hierarchical Bayesian techniques, we jointly analyzed the correlations between tasks within individuals-reflecting the degree to which tasks rely on shared cognitive processes-and within items-reflecting the degree to which tasks rely on the same information conveyed by the item. Among other things, we find that (a) the processes involved in lexical access and episodic memory are largely separate and rely on different kinds of information, (b) access to lexical memory is driven primarily by perceptual aspects of a word, (c) all episodic memory tasks rely to an extent on a set of shared processes which make use of semantic features to encode both single words and associations between words, and (d) recall involves additional processes likely related to contextual cuing and response production. These results provide a large-scale picture of memory across different tasks which can serve to drive the development of comprehensive theories of memory. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Brain processing of task-relevant and task-irrelevant emotional words: an ERP study.

Science.gov (United States)

González-Villar, Alberto J; Triñanes, Yolanda; Zurrón, Montserrat; Carrillo-de-la-Peña, María T

2014-09-01

Although there is evidence for preferential perceptual processing of written emotional information, the effects of attentional manipulations and the time course of affective processing require further clarification. In this study, we attempted to investigate how the emotional content of words modulates cerebral functioning (event-related potentials, ERPs) and behavior (reaction times, RTs) when the content is task-irrelevant (emotional Stroop Task, EST) or task-relevant (emotional categorization task, ECT), in a sample of healthy middle-aged women. In the EST, the RTs were longer for emotional words than for neutral words, and in the ECT, they were longer for neutral and negative words than for positive words. A principal components analysis of the ERPs identified various temporospatial factors that were differentially modified by emotional content. P2 was the first emotion-sensitive component, with enhanced factor scores for negative nouns across tasks. The N2 and late positive complex had enhanced factor scores for emotional relative to neutral information only in the ECT. The results reinforce the idea that written emotional information has a preferential processing route, both when it is task-irrelevant (producing behavioral interference) and when it is task-relevant (facilitating the categorization). After early automatic processing of the emotional content, late ERPs become more emotionally modulated as the level of attention to the valence increases.

Task-related modulation of visual neglect in cancellation tasks

OpenAIRE

Sarri, Margarita; Greenwood, Richard; Kalra, Lalit; Driver, Jon

2008-01-01

Unilateral neglect involves deficits of spatial exploration and awareness that do not always affect a fixed portion of extrapersonal space, but may vary with current stimulation and possibly with task demands. Here, we assessed any ‘top-down’, task-related influences on visual neglect, with novel experimental variants of the cancellation test. Many different versions of the cancellation test are used clinically, and can differ in the extent of neglect revealed, though the exact factors determ...

Allocating time to future tasks: the effect of task segmentation on planning fallacy bias.

Science.gov (United States)

Forsyth, Darryl K; Burt, Christopher D B

2008-06-01

The scheduling component of the time management process was used as a "paradigm" to investigate the allocation of time to future tasks. In three experiments, we compared task time allocation for a single task with the summed time allocations given for each subtask that made up the single task. In all three, we found that allocated time for a single task was significantly smaller than the summed time allocated to the individual subtasks. We refer to this as the segmentation effect. In Experiment 3, we asked participants to give estimates by placing a mark on a time line, and found that giving time allocations in the form of rounded close approximations probably does not account for the segmentation effect. We discuss the results in relation to the basic processes used to allocate time to future tasks and the means by which planning fallacy bias might be reduced.

Is Performance in Task-Cuing Experiments Mediated by Task Set Selection or Associative Compound Retrieval?

Science.gov (United States)

Forrest, Charlotte L. D.; Monsell, Stephen; McLaren, Ian P. L.

2014-01-01

Task-cuing experiments are usually intended to explore control of task set. But when small stimulus sets are used, they plausibly afford learning of the response associated with a combination of cue and stimulus, without reference to tasks. In 3 experiments we presented the typical trials of a task-cuing experiment: a cue (colored shape) followed,…

Measuring moment-to-moment pilot workload using synchronous presentations of secondary tasks in a motion-base trainer

Science.gov (United States)

Bortolussi, Michael R.; Hart, Sandra G.; Shively, Robert J.

1987-01-01

A simulation was conducted to determine whether the sensitivity of secondary task measures of pilot workload could be improved by synchronizing their presentation to the occurrence of specific events or pilot actions. This synchronous method of presentation was compared to the more typical asynchronous method, where secondary task presentations are independent of pilot's flight-related activities. Twelve pilots flew low- and high-difficulty scenarios in a motion-base trainer with and without concurrent secondary tasks (e.g., choice reaction time and time production). The difficulty of each scenario was manipulated by the addition of 21 flight-related tasks superimposed on a standard approach and landing sequence. The insertion of the secondary tasks did not affect primary flight performance. However, secondary task performance did reflect workload differences between scenarios and among flight segments within scenarios, replicating the results of an earlier study in which the secondary tasks were presented asynchronously (Bortolussi et al., 1986).

Variable Lifting Index (VLI): A New Method for Evaluating Variable Lifting Tasks.

Science.gov (United States)

Waters, Thomas; Occhipinti, Enrico; Colombini, Daniela; Alvarez-Casado, Enrique; Fox, Robert

2016-08-01

We seek to develop a new approach for analyzing the physical demands of highly variable lifting tasks through an adaptation of the Revised NIOSH (National Institute for Occupational Safety and Health) Lifting Equation (RNLE) into a Variable Lifting Index (VLI). There are many jobs that contain individual lifts that vary from lift to lift due to the task requirements. The NIOSH Lifting Equation is not suitable in its present form to analyze variable lifting tasks. In extending the prior work on the VLI, two procedures are presented to allow users to analyze variable lifting tasks. One approach involves the sampling of lifting tasks performed by a worker over a shift and the calculation of the Frequency Independent Lift Index (FILI) for each sampled lift and the aggregation of the FILI values into six categories. The Composite Lift Index (CLI) equation is used with lifting index (LI) category frequency data to calculate the VLI. The second approach employs a detailed systematic collection of lifting task data from production and/or organizational sources. The data are organized into simplified task parameter categories and further aggregated into six FILI categories, which also use the CLI equation to calculate the VLI. The two procedures will allow practitioners to systematically employ the VLI method to a variety of work situations where highly variable lifting tasks are performed. The scientific basis for the VLI procedure is similar to that for the CLI originally presented by NIOSH; however, the VLI method remains to be validated. The VLI method allows an analyst to assess highly variable manual lifting jobs in which the task characteristics vary from lift to lift during a shift. © 2015, Human Factors and Ergonomics Society.

Dividing attention between tasks : Testing whether explicit payoff functions elicit optimal dual-task performance

NARCIS (Netherlands)

Farmer, George D.; Janssen, C.P.|info:eu-repo/dai/nl/412781654; Nguyen, Anh T; Brumby, Duncan P.

2018-01-01

We test people's ability to optimize performance across two concurrent tasks. Participants performed a number entry task while controlling a randomly moving cursor with a joystick. Participants received explicit feedback on their performance on these tasks in the form of a single combined score.

Physical Education-in-CLIL tasks. Determining tasks characteristics through the analysis of the diaries

Directory of Open Access Journals (Sweden)

Josep Coral Mateu

2013-07-01

Full Text Available This article focuses on the characteristics of Physical Education-in-CLIL (PE-in-CLIL tasks. CLIL (Content and Language Integrated Learning is a teaching approach which uses foreign language as a tool to enhance the subject learning process. We connect PE-in-CLIL with key competences and we introduce the CLIL 4Cs framework. We establish the aims of the study, that is; to describe the features of tasks which are most suitable to PE-in-CLIL and identify integrated tasks which appeal most to learners. We use Action-Research and we collect data through diaries. The participants of the study were twenty-six learners of 5th grade of primary school. We described the strategies of rigour and quality applied and we analysed data using a qualitative data analysis software programme (NVivo. In the results, we identify both the tasks that appeal to students and the tasks that are developed successfully. In the conclusions, we provide teaching guidelines to plan successful PE-in-CLIL tasks that appeal to students. At this point, we emphasise tasks that combined both cooperative learning and oracy with motor activity and games. We also declare the necessity of incorporating scaffolding strategies in order to accommodate students’ linguistic needs and facilitate tasks development. Future CLIL research possibilities emerge in the Physical Education field of work.

Use of OECD/NEA Data Project Products in Probabilistic Safety Assessment

International Nuclear Information System (INIS)

Cherkas, G.; Raducu, Gheorghe; Riznic, J.; Yalaoui, S.; Huang, Hui-Wen; Holy, Jaroslav; Holmberg, Jan-Erik; Sandberg, Jorma; Balmain, Michel; Bonnevialle, Anne-Marie; Curnier, Florence; Georgescu, Gabriel; Lanore, Jeanne-Marie; Lindner, Arndt; Fujimoto, Haruo; Ahn, Kwang-Il; Hwang, Taesuk; Jang, Seung-Cheol; Husarcek, Jan; Kovacs, Zoltan; Vazquez, Teresa; Johanson, Gunnar; Liwaang, Bo; Nyman, Ralph; Dang, Vinh; Schoen, Gerhard; Brook, Kevin; Hamblen, David; Siu, Nathan; Sturzebecher, Karl; Tobin, Margaret; Wood, Jeff; Amri, Abdallah; Breest, Axel

2014-01-01

The Nuclear Energy Agency (NEA)/Committee for the Safety of Nuclear Installations' (CSNI) Working Group on Risk Assessment (WGRISK) is tasked with supporting the improved use of Probabilistic Safety Assessment (PSA) in risk informed regulation and safety management through the analysis of results and the development of perspectives regarding potentially important risk contributors and associated risk reduction strategies. The task consists of the following major activities: Development, distribution, and completion of survey questionnaires; Analysis of survey questionnaire results at a task workshop; Preparation of the final task report. The main objectives of this task, as proposed by WGRISK and approved by CSNI, are the following: - Identification and characterization of the current uses of OECD data project products and data in support of PSA. In this context, the term 'products' refers to data analysis results, technical reports, and other project outputs. - Identification and characterization of technical and programmatic characteristics that either support or impede use of data project products in PSA. This includes an assessment of which PSA parameters could be potentially estimated from the various data project products and gaps between available product information and PSA data needs. - Identification of recommendations for enhancing the usefulness of data project products and the coordination between WGRISK and the data projects. This task report consists of the following sections: - Chapter 1 Provides a general overview of motivation and approach used for this task. - Chapter 2 Describes scope and objectives of the task. - Chapter 3 Provides an overview of the ICDE, FIRE, OPDE/CODAP, and COMPSIS data projects. For each project, the project objectives, project history, data collection methodology and quality assurance, project status, example PSA Applications, and information related to project participation is provided. - Chapter 4 Describes the

Offshoring as an Exogenous Shock to the Services Production System

DEFF Research Database (Denmark)

Brandl, Kristin; Mol, Michael; Petersen, Bent

Production of services involves three key elements, an output for the client, resources of a provider and task execution. Offshoring of services acts as an exogenous shock to such a production system. Using multiple case methodology we investigate how task output, execution, and resources change...... as a consequence of offshoring and particularly how these elements are realigned. The cases reveal substantial managerial challenges in the alignment process prompted by a relocation of service task execution to an emerging economy. In particular, we find that instead of some set of capabilities that proactively...

The Relationship between Working Memory Capacity and L2 Oral Performance under Task-Based Careful Online Planning Condition

Science.gov (United States)

Ahmadian, Mohammad Javad

2012-01-01

The study reported in this article aimed to investigate the way working memory capacity (WMC) interacts with careful online planning--a task-based implementation variable--to affect second language (L2) speech production. This issue is important to teachers, because it delves into one of the possible task-based implementation variables and thus…

Succumbing to Bottom-Up Biases on Task Choice Predicts Increased Switch Costs in the Voluntary Task Switching Paradigm

Science.gov (United States)

Orr, Joseph M.; Weissman, Daniel H.

2010-01-01

Bottom-up biases are widely thought to influence task choice in the voluntary task switching paradigm. Definitive support for this hypothesis is lacking, however, because task choice and task performance are usually confounded. We therefore revisited this hypothesis using a paradigm in which task choice and task performance are temporally separated. As predicted, participants tended to choose the task that was primed by bottom-up biases. Moreover, such choices were linked to increased switch costs during subsequent task performance. These findings provide compelling evidence that bottom-up biases influence voluntary task choice. They also suggest that succumbing to such biases reflects a reduction of top-down control that persists to influence upcoming task performance. PMID:21713192

Dual-Task Walking in Challenging Environments in People with Stroke: Cognitive-Motor Interference and Task Prioritization

Directory of Open Access Journals (Sweden)

Celine Timmermans

2018-01-01

Full Text Available Cognitive-motor interference may contribute to the risk of falling in people with stroke, as may be the associated phenomenon of inappropriate task prioritization. Examining dual-task walking could provide valuable insights as to how to best evaluate and treat walking in people with stroke. This study aimed to examine the effect of different walking environments on cognitive-motor interference and task prioritization in dual-task walking in people with stroke. Using a repeated-measures design, cognitive-motor interference and task prioritization were assessed in 30 stroke survivors, while walking in a plain environment and in two challenging environments that were enriched with either stationary physical context or suddenly appearing projector-augmented context. All three walking environment conditions were performed with and without a concurrent serial-3 subtraction task. We found stronger cognitive-motor interference for the two challenging environments than for the plain walking environment. Cognitive-motor interference did not differ between challenging walking environments, but task prioritization did: motor performance was prioritized more in the environment with physical context than in the environment with projector-augmented context and vice versa for cognitive-task performance. In conclusion, walking environment strongly influenced cognitive-motor interference and task prioritization during dual-task walking in people with stroke.

Task Selection, Task Switching and Multitasking during Computer-Based Independent Study

Science.gov (United States)

Judd, Terry

2015-01-01

Detailed logs of students' computer use, during independent study sessions, were captured in an open-access computer laboratory. Each log consisted of a chronological sequence of tasks representing either the application or the Internet domain displayed in the workstation's active window. Each task was classified using a three-tier schema…

ANALYSIS OF LEGAL AND METHODOLOGICAL GROUNDS FOR RISK-ORIENTED SURVEILLANCE OVER CONSUMER PRODUCTS: TASKS AND DEVELOPMENT PROSPECTS IN THE EURASIAN ECONOMIC UNION

Directory of Open Access Journals (Sweden)

N.V. Zaitseva

2017-12-01

Full Text Available The paper dwells on basic legal and sub-legislative documents issued in the EU, the USA, Canada, by the WTO and Codex Alimentarius Commission which provide control of consumer products safety on the basis of assessing risks for consumers' life and health. Risk-oriented surveillance is shown as a system which makes for lower loads on business but still provides systemic control over most hazardous products. The EU legislation fixes the right to perform supranational control over state control systems existing in the EU member states in terms of their relevance and legitimacy. This supranational control is supported by organizational structures and regulatory and methodological documents. National control systems are systematically reviewed and analyzed in order to secure their conformity to supranational regulatory acts, to detect any cases of non-compliance, and to spread the best practices. Risk analysis reviews and results are open and discussable. As a result of products hazards assessment their turnover can be limited, or they can be withdrawn from the market, or additional information on hazards or risks they may cause is to be provided for consumers. Public and constantly operating systems of informing about hazardous goods are well-developed. International experience and practices in the sphere of risk-oriented surveillance over consumer products can be and should be applied in the Eurasian Economic Union (EEU countries. The Eurasian Economic Union countries fix orientation at observing consumer goods safety principles in their legislation. There are also legal grounds for and practices in the sphere of risk-oriented approach to products manufactures. But it is necessary to further develop a products classification system as per consumer health risk parameters. And this task requires working out unified approaches to classification of both eatable and non-eatable products. It seems relevant to develop a public analytical database of risk

Constructing knowledge for teaching secondary mathematics tasks to enhance prospective and practicing teacher learning

CERN Document Server

Zaslavsky, Orit

2010-01-01

This book offers a unifed approach to tasks used in the education of secondary mathematics teachers, based on broad goals such as adaptability, identifying similarities, productive disposition, overcoming barriers, micro simulations, choosing tools, and more.

Dynamic, continuous multitasking training leads to task-specific improvements but does not transfer across action selection tasks

Science.gov (United States)

Bender, Angela D.; Filmer, Hannah L.; Naughtin, Claire K.; Dux, Paul E.

2017-12-01

The ability to perform multiple tasks concurrently is an ever-increasing requirement in our information-rich world. Despite this, multitasking typically compromises performance due to the processing limitations associated with cognitive control and decision-making. While intensive dual-task training is known to improve multitasking performance, only limited evidence suggests that training-related performance benefits can transfer to untrained tasks that share overlapping processes. In the real world, however, coordinating and selecting several responses within close temporal proximity will often occur in high-interference environments. Over the last decade, there have been notable reports that training on video action games that require dynamic multitasking in a demanding environment can lead to transfer effects on aspects of cognition such as attention and working memory. Here, we asked whether continuous and dynamic multitasking training extends benefits to tasks that are theoretically related to the trained tasks. To examine this issue, we asked a group of participants to train on a combined continuous visuomotor tracking task and a perceptual discrimination task for six sessions, while an active control group practiced the component tasks in isolation. A battery of tests measuring response selection, response inhibition, and spatial attention was administered before and immediately after training to investigate transfer. Multitasking training resulted in substantial, task-specific gains in dual-task ability, but there was no evidence that these benefits generalized to other action control tasks. The findings suggest that training on a combined visuomotor tracking and discrimination task results in task-specific benefits but provides no additional value for untrained action selection tasks.

Multicriteria Evaluation of Product Quality

OpenAIRE

Pabedinskaitė, Arnoldina; Vitkauskas, Romualdas

2009-01-01

Product quality assessment is a complex task. The aim of this paper is to analyse the concepts of quality, different quality management models and their interaction with knowledge management models and the presented criteria system for assessing product quality. Moreover, multicriteria methods and their applicability to assessment of the product quality are analysed. On the basis of group of the product quality criteria and using the multicriteria evaluation methods, the quality of the produc...

Performing Task Integration

DEFF Research Database (Denmark)

Elkjaer, Bente; Nickelsen, Niels Christian Mossfeldt

by shared goals and knowledge as well as mutual respect and frequent, timely, accurate and problem-solving ways of communication with the purpose of dealing with the tasks at hand in an integrated way. We introduce and discuss relational coordination theory through a case-study within public healthcare....... Here cross-professional coordination of work was done by scheduled communication twice a day. When we proposed a way for further integration of tasks through an all-inclusive team organization, we were met with resistance. We use the study to discuss whether relational coordination theory is able to do...... away with differences regarding task definitions and working conditions as well as professional knowledge hierarchies and responsibilities for parts and wholes....

Outsourcing Agricultural Production: Evidence from Rice Farmers in Zhejiang Province.

Directory of Open Access Journals (Sweden)

Chen Ji

Full Text Available China has recorded positive growth rates of grain production for the past eleven consecutive years. This is a remarkable accomplishment given that China's rapid industrialization and urbanization has led to a vast reduction of arable land and agricultural labor to non-agricultural sectors. While there are many factors contributing to this happy outcome, one potential contributing factor that has received increasing attention is the emergence of agricultural production outsourcing, a new rural institution that has emerged in recent years. This study aims to contribute to the limited but growing literature on agricultural production outsourcing in China. Specifically, this study analyzes factors affecting farmers' decisions to outsource any or some production tasks using data from rice farmers in Zhejiang province. Results from a logistic model show that farm size and government subsidy encourages farmers to outsource while ownership of agricultural machines and land fragmentation have negative effects on farmers' decisions to outsource production tasks. Results also showed that determinants of outsourcing decisions vary with the production tasks that farmers outsourced.

Outsourcing Agricultural Production: Evidence from Rice Farmers in Zhejiang Province.

Science.gov (United States)

Ji, Chen; Guo, Hongdong; Jin, Songqing; Yang, Jin

2017-01-01

China has recorded positive growth rates of grain production for the past eleven consecutive years. This is a remarkable accomplishment given that China's rapid industrialization and urbanization has led to a vast reduction of arable land and agricultural labor to non-agricultural sectors. While there are many factors contributing to this happy outcome, one potential contributing factor that has received increasing attention is the emergence of agricultural production outsourcing, a new rural institution that has emerged in recent years. This study aims to contribute to the limited but growing literature on agricultural production outsourcing in China. Specifically, this study analyzes factors affecting farmers' decisions to outsource any or some production tasks using data from rice farmers in Zhejiang province. Results from a logistic model show that farm size and government subsidy encourages farmers to outsource while ownership of agricultural machines and land fragmentation have negative effects on farmers' decisions to outsource production tasks. Results also showed that determinants of outsourcing decisions vary with the production tasks that farmers outsourced.

Efficient task assignment in spatial crowdsourcing with worker and task privacy protection

KAUST Repository

Liu, An

2017-08-01

Spatial crowdsourcing (SC) outsources tasks to a set of workers who are required to physically move to specified locations and accomplish tasks. Recently, it is emerging as a promising tool for emergency management, as it enables efficient and cost-effective collection of critical information in emergency such as earthquakes, when search and rescue survivors in potential ares are required. However in current SC systems, task locations and worker locations are all exposed in public without any privacy protection. SC systems if attacked thus have penitential risk of privacy leakage. In this paper, we propose a protocol for protecting the privacy for both workers and task requesters while maintaining the functionality of SC systems. The proposed protocol is built on partially homomorphic encryption schemes, and can efficiently realize complex operations required during task assignment over encrypted data through a well-designed computation strategy. We prove that the proposed protocol is privacy-preserving against semi-honest adversaries. Simulation on two real-world datasets shows that the proposed protocol is more effective than existing solutions and can achieve mutual privacy-preserving with acceptable computation and communication cost.

Hybrid glowworm swarm optimization for task scheduling in the cloud environment

Science.gov (United States)

Zhou, Jing; Dong, Shoubin

2018-06-01

In recent years many heuristic algorithms have been proposed to solve task scheduling problems in the cloud environment owing to their optimization capability. This article proposes a hybrid glowworm swarm optimization (HGSO) based on glowworm swarm optimization (GSO), which uses a technique of evolutionary computation, a strategy of quantum behaviour based on the principle of neighbourhood, offspring production and random walk, to achieve more efficient scheduling with reasonable scheduling costs. The proposed HGSO reduces the redundant computation and the dependence on the initialization of GSO, accelerates the convergence and more easily escapes from local optima. The conducted experiments and statistical analysis showed that in most cases the proposed HGSO algorithm outperformed previous heuristic algorithms to deal with independent tasks.

Are factors related to dual-task performance in people with Parkinson's disease dependent on the type of dual task?

Science.gov (United States)

Strouwen, Carolien; Molenaar, Esther A L M; Keus, Samyra H J; Münks, Liesbeth; Heremans, Elke; Vandenberghe, Wim; Bloem, Bastiaan R; Nieuwboer, Alice

2016-02-01

Impaired dual-task performance significantly impacts upon functional mobility in people with Parkinson's disease (PD). The aim of this study was to identify determinants of dual-task performance in people with PD in three different dual tasks to assess their possible task-dependency. We recruited 121 home-dwelling patients with PD (mean age 65.93 years; mean disease duration 8.67 years) whom we subjected to regular walking (control condition) and to three dual-task conditions: walking combined with a backwards Digit Span task, an auditory Stroop task and a Mobile Phone task. We measured dual-task gait velocity using the GAITRite mat and dual-task reaction times and errors on the concurrent tasks as outcomes. Motor, cognitive and descriptive variables which correlated to dual-task performance (p task gait velocity and executive function, tested by the alternating intake test, was significantly associated with gait velocity during the Digit Span (R(2) = 0.65; p task (R(2) = 0.62; p task. Age was a surplus determinant of gait velocity while using a mobile phone. Single-task gait velocity and executive function as measured by a verbal fluency switching task were independent determinants of dual-task gait performance in people with PD. In contrast to expectation, these factors were the same across different tasks, supporting the robustness of the findings. Future study needs to determine whether these factors predict dual-task abnormalities prospectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Efficient task assignment in spatial crowdsourcing with worker and task privacy protection

KAUST Repository

Liu, An; Wang, Weiqi; Shang, Shuo; Li, Qing; Zhang, Xiangliang

2017-01-01

Spatial crowdsourcing (SC) outsources tasks to a set of workers who are required to physically move to specified locations and accomplish tasks. Recently, it is emerging as a promising tool for emergency management, as it enables efficient and cost

Locus of Semantic Interference in Picture Naming: Evidence from Dual-Task Performance

Science.gov (United States)

Piai, Vitória; Roelofs, Ardi; Schriefers, Herbert

2014-01-01

Disagreement exists regarding the functional locus of semantic interference of distractor words in picture naming. This effect is a cornerstone of modern psycholinguistic models of word production, which assume that it arises in lexical response-selection. However, recent evidence from studies of dual-task performance suggests a locus in…

Planning, Implementing, and Assessing an Authentic Performance Task in Middle Grades Classrooms

Science.gov (United States)

Barnes, Nicole C.; Urbankowski, Daniel

2014-01-01

As young adolescents, middle grades students experience a wide variety of changes related to their cognitive capabilities, social and emotional well-being, and use of self-regulation strategies. Authentic performance tasks challenge students to apply their knowledge and skills to realistic problems to create products or performances--consistent…

Intuitive Robot Tasks with Augmented Reality and Virtual Obstacles

OpenAIRE

Gaschler, Andre;Springer, Maximilian;Rickert, Markus;Knoll, Alois

2017-01-01

Today's industrial robots require expert knowledge and are not profitable for small and medium sized enterprises with their small lot sizes. It is our strong belief that more intuitive robot programming in an augmented reality robot work cell can dramatically simplify re-programming and leverage robotics technology in short production cycles. In this paper, we present a novel augmented reality system for defining virtual obstacles, specifying tool positions, and specifying robot tasks. We eva...

The economic production of alcohol fuels from coal-derived synthesis gas

Energy Technology Data Exchange (ETDEWEB)

Kugler, E.L.; Dadyburjor, D.B.; Yang, R.Y.K. [West Virginia Univ., Morgantown, WV (United States)] [and others

1995-12-31

The objectives of this project are to discover, (1) study and evaluate novel heterogeneous catalytic systems for the production of oxygenated fuel enhancers from synthesis gas. Specifically, alternative methods of preparing catalysts are to be investigated, and novel catalysts, including sulfur-tolerant ones, are to be pursued. (Task 1); (2) explore, analytically and on the bench scale, novel reactor and process concepts for use in converting syngas to liquid fuel products. (Task 1); (3) simulate by computer the most energy efficient and economically efficient process for converting coal to energy, with primary focus on converting syngas to fuel alcohols. (Task 2); (4) develop on the bench scale the best holistic combination of chemistry, catalyst, reactor and total process configuration integrated with the overall coal conversion process to achieve economic optimization for the conversion of syngas to liquid products within the framework of achieving the maximum cost effective transformation of coal to energy equivalents. (Tasks 1 and 2); and (5) evaluate the combustion, emission and performance characteristics of fuel alcohols and blends of alcohols with petroleum-based fuels. (Task 2)

Task-dependent changes of corticospinal excitability during observation and motor imagery of balance tasks.

Science.gov (United States)

Mouthon, A; Ruffieux, J; Wälchli, M; Keller, M; Taube, W

2015-09-10

Non-physical balance training has demonstrated to be efficient to improve postural control in young people. However, little is known about the potential to increase corticospinal excitability by mental simulation in lower leg muscles. Mental simulation of isolated, voluntary contractions of limb muscles increase corticospinal excitability but more automated tasks like walking seem to have no or only minor effects on motor-evoked potentials (MEPs) evoked by transcranial magnetic stimulation (TMS). This may be related to the way of performing the mental simulation or the task itself. Therefore, the present study aimed to clarify how corticospinal excitability is modulated during AO+MI, MI and action observation (AO) of balance tasks. For this purpose, MEPs and H-reflexes were elicited during three different mental simulations (a) AO+MI, (b) MI and (c) passive AO. For each condition, two balance tasks were evaluated: (1) quiet upright stance (static) and (2) compensating a medio-lateral perturbation while standing on a free-swinging platform (dynamic). AO+MI resulted in the largest facilitation of MEPs followed by MI and passive AO. MEP facilitation was significantly larger in the dynamic perturbation than in the static standing task. Interestingly, passive observation resulted in hardly any facilitation independent of the task. H-reflex amplitudes were not modulated. The current results demonstrate that corticospinal excitability during mental simulation of balance tasks is influenced by both the type of mental simulation and the task difficulty. As H-reflexes and background EMG were not modulated, it may be argued that changes in excitability of the primary motor cortex were responsible for the MEP modulation. From a functional point of view, our findings suggest best training/rehabilitation effects when combining MI with AO during challenging postural tasks. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Promoting greater Federal energy productivity [Final report

Energy Technology Data Exchange (ETDEWEB)

Hopkins, Mark; Dudich, Luther

2003-03-05

This document is a close-out report describing the work done under this DOE grant to improve Federal Energy Productivity. Over the four years covered in this document, the Alliance To Save Energy conducted liaison with the private sector through our Federal Energy Productivity Task Force. In this time, the Alliance held several successful workshops on the uses of metering in Federal facilities and other meetings. We also conducted significant research on energy efficiency, financing, facilitated studies of potential energy savings in energy intensive agencies, and undertook other tasks outlined in this report.

The development of a task analysis method applicable to the tasks of nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Yoon, Wan Chul; Park, Ji Soo; Baek, Dong Hyeon; Ham, Dong Han; Kim, Huhn [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1996-07-01

While task analysis is one of the essential processes for human factors studies, traditional methods reveal weaknesses in dealing with the cognitive aspects, which become more critical in modern complex system. This report proposes a cognitive task analysis (CTA) method for identifying cognitive requirements of operators' tasks in nuclear power plants. The proposed CTA method is characterized by the information-oriented concept and procedure-based approach. The task prescription identifies the information requirements and trace the information flow to reveal the cognitive organization of task procedure with emphasis to the relations among the information requirements. The cognitive requirements are then analyzed in terms of cognitive span of task information, cognitive envelope and working memory relief point of t procedures, and working memory load. The proposed method is relatively simple and, possibly being incorporated in a full task analysis scheme, directly applicable to the design/evaluation of human-machine interfaces and operating procedures. A prototype of a computerized support system is developed for supporting the practicality of the proposed method. (Author) 104 refs., 8 tabs., 7 figs.

The development of a task analysis method applicable to the tasks of nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Yoon, Wan Chul; Park, Ji Soo; Baek, Dong Hyeon; Ham, Dong Han; Kim, Huhn [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1996-07-01

While task analysis is one of the essential processes for human factors studies, traditional methods reveal weaknesses in dealing with the cognitive aspects, which become more critical in modern complex system. This report proposes a cognitive task analysis (CTA) method for identifying cognitive requirements of operators' tasks in nuclear power plants. The proposed CTA method is characterized by the information-oriented concept and procedure-based approach. The task prescription identifies the information requirements and trace the information flow to reveal the cognitive organization of task procedure with emphasis to the relations among the information requirements. The cognitive requirements are then analyzed in terms of cognitive span of task information, cognitive envelope and working memory relief point of t procedures, and working memory load. The proposed method is relatively simple and, possibly being incorporated in a full task analysis scheme, directly applicable to the design/evaluation of human-machine interfaces and operating procedures. A prototype of a computerized support system is developed for supporting the practicality of the proposed method. (Author) 104 refs., 8 tabs., 7 figs.

Secondary task for full flight simulation incorporating tasks that commonly cause pilot error: Time estimation

Science.gov (United States)

Rosch, E.

1975-01-01

The task of time estimation, an activity occasionally performed by pilots during actual flight, was investigated with the objective of providing human factors investigators with an unobtrusive and minimally loading additional task that is sensitive to differences in flying conditions and flight instrumentation associated with the main task of piloting an aircraft simulator. Previous research indicated that the duration and consistency of time estimates is associated with the cognitive, perceptual, and motor loads imposed by concurrent simple tasks. The relationships between the length and variability of time estimates and concurrent task variables under a more complex situation involving simulated flight were clarified. The wrap-around effect with respect to baseline duration, a consequence of mode switching at intermediate levels of concurrent task distraction, should contribute substantially to estimate variability and have a complex effect on the shape of the resulting distribution of estimates.

Pre-task music improves swimming performance.

Science.gov (United States)

Smirmaul, B P; Dos Santos, R V; Da Silva Neto, L V

2015-12-01

The purpose of this study was to investigate the effects of pre-task music on swimming performance and other psychological variables. A randomized counterbalanced within-subjects (experimental and control condition) design was employed. Eighteen regional level male swimmers performed two 200-m freestyle swimming time trials. Participants were exposed to either 5 minutes of self-selected music (pre-task music condition) or 5 minutes of silence (control condition) and, after 1 minute, performed the swimming task. Swimming time was significantly shorter (-1.44%) in the pre-task music condition. Listening to pre-task music increased motivation to perform the swimming task, while arousal remained unchanged. While fatigue increased after the swimming task in both conditions, vigor, ratings of perceived exertion and affective valence were unaltered. It is concluded, for the first time, that pre-task music improves swimming performance.

The sentence verification task: a reliable fMRI protocol for mapping receptive language in individual subjects

International Nuclear Information System (INIS)

Sanjuan, Ana; Avila, Cesar; Forn, Cristina; Ventura-Campos, Noelia; Rodriguez-Pujadas, Aina; Garcia-Porcar, Maria; Belloch, Vicente; Villanueva, Vicente

2010-01-01

To test the capacity of a sentence verification (SV) task to reliably activate receptive language areas. Presurgical evaluation of language is useful in predicting postsurgical deficits in patients who are candidates for neurosurgery. Productive language tasks have been successfully elaborated, but more conflicting results have been found in receptive language mapping. Twenty-two right-handed healthy controls made true-false semantic judgements of brief sentences presented auditorily. Group maps showed reliable functional activations in the frontal and temporoparietal language areas. At the individual level, the SV task showed activation located in receptive language areas in 100% of the participants with strong left-sided distributions (mean lateralisation index of 69.27). The SV task can be considered a useful tool in evaluating receptive language function in individual subjects. This study is a first step towards designing the fMRI task which may serve to presurgically map receptive language functions. (orig.)

The sentence verification task: a reliable fMRI protocol for mapping receptive language in individual subjects

Energy Technology Data Exchange (ETDEWEB)

Sanjuan, Ana; Avila, Cesar [Universitat Jaume I, Departamento de Psicologia Basica, Clinica y Psicobiologia, Castellon de la Plana (Spain); Hospital La Fe, Unidad de Epilepsia, Servicio de Neurologia, Valencia (Spain); Forn, Cristina; Ventura-Campos, Noelia; Rodriguez-Pujadas, Aina; Garcia-Porcar, Maria [Universitat Jaume I, Departamento de Psicologia Basica, Clinica y Psicobiologia, Castellon de la Plana (Spain); Belloch, Vicente [Hospital La Fe, Eresa, Servicio de Radiologia, Valencia (Spain); Villanueva, Vicente [Hospital La Fe, Unidad de Epilepsia, Servicio de Neurologia, Valencia (Spain)

2010-10-15

To test the capacity of a sentence verification (SV) task to reliably activate receptive language areas. Presurgical evaluation of language is useful in predicting postsurgical deficits in patients who are candidates for neurosurgery. Productive language tasks have been successfully elaborated, but more conflicting results have been found in receptive language mapping. Twenty-two right-handed healthy controls made true-false semantic judgements of brief sentences presented auditorily. Group maps showed reliable functional activations in the frontal and temporoparietal language areas. At the individual level, the SV task showed activation located in receptive language areas in 100% of the participants with strong left-sided distributions (mean lateralisation index of 69.27). The SV task can be considered a useful tool in evaluating receptive language function in individual subjects. This study is a first step towards designing the fMRI task which may serve to presurgically map receptive language functions. (orig.)

ANALYSIS OF THE GAZE BEHAVIOUR OF THE WORKER ON THE CARBURETOR ASSEMBLY TASK

Directory of Open Access Journals (Sweden)

Novie Susanto

2015-06-01

Full Text Available This study presents analysis of the area of interest (AOI and the gaze behavior of human during assembly task. This study aims at investigating the human behavior in detail using an eye‐tracking system during assembly task using LEGO brick and an actual manufactured product, a carburetor. An analysis using heat map data based on the recorded videos from the eye-tracking system is taken into account to examine and investigate the gaze behavior of human. The results of this study show that the carburetor assembly requires more attention than the product made from LEGO bricks. About 50% of the participants experience the necessity to visually inspect the interim state of the work object during the simulation of the assembly sequence on the screen. They also show the tendency to want to be more certain about part fitting in the actual work object.

Decision paths in complex tasks

Science.gov (United States)

Galanter, Eugene

1991-01-01

Complex real world action and its prediction and control has escaped analysis by the classical methods of psychological research. The reason is that psychologists have no procedures to parse complex tasks into their constituents. Where such a division can be made, based say on expert judgment, there is no natural scale to measure the positive or negative values of the components. Even if we could assign numbers to task parts, we lack rules i.e., a theory, to combine them into a total task representation. We compare here two plausible theories for the amalgamation of the value of task components. Both of these theories require a numerical representation of motivation, for motivation is the primary variable that guides choice and action in well-learned tasks. We address this problem of motivational quantification and performance prediction by developing psychophysical scales of the desireability or aversiveness of task components based on utility scaling methods (Galanter 1990). We modify methods used originally to scale sensory magnitudes (Stevens and Galanter 1957), and that have been applied recently to the measure of task 'workload' by Gopher and Braune (1984). Our modification uses utility comparison scaling techniques which avoid the unnecessary assumptions made by Gopher and Braune. Formula for the utility of complex tasks based on the theoretical models are used to predict decision and choice of alternate paths to the same goal.

Multi-task Vector Field Learning.

Science.gov (United States)

Lin, Binbin; Yang, Sen; Zhang, Chiyuan; Ye, Jieping; He, Xiaofei

2012-01-01

Multi-task learning (MTL) aims to improve generalization performance by learning multiple related tasks simultaneously and identifying the shared information among tasks. Most of existing MTL methods focus on learning linear models under the supervised setting. We propose a novel semi-supervised and nonlinear approach for MTL using vector fields. A vector field is a smooth mapping from the manifold to the tangent spaces which can be viewed as a directional derivative of functions on the manifold. We argue that vector fields provide a natural way to exploit the geometric structure of data as well as the shared differential structure of tasks, both of which are crucial for semi-supervised multi-task learning. In this paper, we develop multi-task vector field learning (MTVFL) which learns the predictor functions and the vector fields simultaneously. MTVFL has the following key properties. (1) The vector fields MTVFL learns are close to the gradient fields of the predictor functions. (2) Within each task, the vector field is required to be as parallel as possible which is expected to span a low dimensional subspace. (3) The vector fields from all tasks share a low dimensional subspace. We formalize our idea in a regularization framework and also provide a convex relaxation method to solve the original non-convex problem. The experimental results on synthetic and real data demonstrate the effectiveness of our proposed approach.

Functional localization of a "Time Keeper" function separate from attentional resources and task strategy.

Science.gov (United States)

Tracy, J I; Faro, S H; Mohamed, F B; Pinsk, M; Pinus, A

2000-03-01

The functional neuroanatomy of time estimation has not been well-documented. This research investigated the fMRI measured brain response to an explicit, prospective time interval production (TIP) task. The study tested for the presence of brain activity reflecting a primary time keeper function, distinct from the brain systems involved either in conscious strategies to monitor time or attentional resource and other cognitive processes to accomplish the task. In the TIP task participants were given a time interval and asked to indicate when it elapsed. Two control tasks (counting forwards, backwards) were administered, in addition to a dual task format of the TIP task. Whole brain images were collected at 1.5 Tesla. Analyses (n = 6) yielded a statistical parametric map (SPM ¿z¿) reflecting time keeping and not strategy (counting, number manipulation) or attention resource utilization. Additional SPM ¿z¿s involving activation associated with the accuracy and magnitude the of time estimation response are presented. Results revealed lateral cerebellar and inferior temporal lobe activation were associated with primary time keeping. Behavioral data provided evidence that the procedures for the explicit time judgements did not occur automatically and utilized controlled processes. Activation sites associated with accuracy, magnitude, and the dual task provided indications of the other structures involved in time estimation that implemented task components related to controlled processing. The data are consistent with prior proposals that the cerebellum is a repository of codes for time processing, but also implicate temporal lobe structures for this type of time estimation task. Copyright 2000 Academic Press.

Generic task problem descriptions: Category B, C, and D tasks

International Nuclear Information System (INIS)

1978-06-01

This document contains information relating to Category B, C, and D generic technical activities. The specific information provided for each task includes the reactor type to which the generic issue applies, the NRC division with lead responsibility and a description of the problem to be addressed by the task. Also provided in this document is a listing of Category A generic technical activities and definitions of Priority Categories A, B, C, and D

Children's attention to task-relevant information accounts for relations between language and spatial cognition.

Science.gov (United States)

Miller, Hilary E; Simmering, Vanessa R

2018-08-01

Children's spatial language reliably predicts their spatial skills, but the nature of this relation is a source of debate. This investigation examined whether the mechanisms accounting for such relations are specific to language use or reflect a domain-general mechanism of selective attention. Experiment 1 examined whether 4-year-olds' spatial skills were predicted by their selective attention or their adaptive language use. Children completed (a) an attention task assessing attention to task-relevant color, size, and location cues; (b) a description task assessing adaptive language use to describe scenes varying in color, size, and location; and (c) three spatial tasks. There was correspondence between the cue types that children attended to and produced across description and attention tasks. Adaptive language use was predicted by both children's attention and task-related language production, suggesting that selective attention underlies skills in using language adaptively. After controlling for age, gender, receptive vocabulary, and adaptive language use, spatial skills were predicted by children's selective attention. The attention score predicted variance in spatial performance previously accounted for by adaptive language use. Experiment 2 followed up on the attention task (Experiment 2a) and description task (Experiment 2b) from Experiment 1 to assess whether performance in the tasks related to selective attention or task-specific demands. Performance in Experiments 2a and 2b paralleled that in Experiment 1, suggesting that the effects in Experiment 1 reflected children's selective attention skills. These findings show that selective attention is a central factor supporting spatial skill development that could account for many effects previously attributed to children's language use. Copyright © 2018 Elsevier Inc. All rights reserved.

Exploring the role of task performance and learning style on prefrontal hemodynamics during a working memory task.

Science.gov (United States)

Anderson, Afrouz A; Parsa, Kian; Geiger, Sydney; Zaragoza, Rachel; Kermanian, Riley; Miguel, Helga; Dashtestani, Hadis; Chowdhry, Fatima A; Smith, Elizabeth; Aram, Siamak; Gandjbakhche, Amir H

2018-01-01

Existing literature outlines the quality and location of activation in the prefrontal cortex (PFC) during working memory (WM) tasks. However, the effects of individual differences on the underlying neural process of WM tasks are still unclear. In this functional near infrared spectroscopy study, we administered a visual and auditory n-back task to examine activation in the PFC while considering the influences of task performance, and preferred learning strategy (VARK score). While controlling for age, results indicated that high performance (HP) subjects (accuracy > 90%) showed task dependent lower activation compared to normal performance subjects in PFC region Specifically HP groups showed lower activation in left dorsolateral PFC (DLPFC) region during performance of auditory task whereas during visual task they showed lower activation in the right DLPFC. After accounting for learning style, we found a correlation between visual and aural VARK score and level of activation in the PFC. Subjects with higher visual VARK scores displayed lower activation during auditory task in left DLPFC, while those with higher visual scores exhibited higher activation during visual task in bilateral DLPFC. During performance of auditory task, HP subjects had higher visual VARK scores compared to NP subjects indicating an effect of learning style on the task performance and activation. The results of this study show that learning style and task performance can influence PFC activation, with applications toward neurological implications of learning style and populations with deficits in auditory or visual processing.

Developmental relationships between speech and writing: is verb-phrase anaphora production a special case?

Science.gov (United States)

Donaldson, Morag L; Cooper, Lynn S M

2013-09-01

Young children's speech is typically more linguistically sophisticated than their writing. However, there are grounds for asking whether production of cohesive devices, such as verb-phrase anaphora (VPA), might represent an exception to this developmental pattern, as cohesive devices are generally more important in writing than in speech and so might be expected to be more frequent in children's writing than in their speech. The study reported herein aims to compare the frequency of children's production of VPA constructions (e.g., Mary is eating an apple and so is John) between a written and a spoken task. Forty-eight children participated from each of two age groups: 7-year-olds and 10-year-olds. All the children received both a spoken and a written sentence completion task designed to elicit production of VPA. Task order was counterbalanced. VPA production was significantly more frequent in speech than in writing and when the spoken task was presented first. Surprisingly, the 7-year-olds produced VPA constructions more frequently than the 10-year-olds. Despite the greater importance of cohesion in writing than in speech, children's production of VPA is similar to their production of most other aspects of language in that more sophisticated constructions are used more frequently in speech than in writing. Children's written production of cohesive devices could probably be enhanced by presenting spoken tasks immediately before written tasks. The lower frequency of VPA production in the older children may reflect syntactic priming effects or a belief that they should produce sentences that are as fully specified as possible. © 2012 The British Psychological Society.

Estimating the operator's performance time of emergency procedural tasks based on a task complexity measure

International Nuclear Information System (INIS)

Jung, Won Dae; Park, Jink Yun

2012-01-01

It is important to understand the amount of time required to execute an emergency procedural task in a high-stress situation for managing human performance under emergencies in a nuclear power plant. However, the time to execute an emergency procedural task is highly dependent upon expert judgment due to the lack of actual data. This paper proposes an analytical method to estimate the operator's performance time (OPT) of a procedural task, which is based on a measure of the task complexity (TACOM). The proposed method for estimating an OPT is an equation that uses the TACOM as a variable, and the OPT of a procedural task can be calculated if its relevant TACOM score is available. The validity of the proposed equation is demonstrated by comparing the estimated OPTs with the observed OPTs for emergency procedural tasks in a steam generator tube rupture scenario.

Caffeine improves anticipatory processes in task switching

NARCIS (Netherlands)

Tieges, Zoe; Snel, Jan; Kok, Albert; Wijnen, Jasper G.; Lorist, Monicque M.; Ridderinkhof, K. Richard

We studied the effects of moderate amounts of caffeine on task switching and task maintenance using mixed-task (AABB) blocks, in which participants alternated predictably between two tasks, and single-task (AAAA, BBBB) blocks. Switch costs refer to longer reaction times (RT) on task switch trials

The task complexity experiment 2003/2004

International Nuclear Information System (INIS)

Laumann, Karin; Braarud, Per Oeivind; Svengren, Haakan

2005-08-01

The purpose of this experiment was to explore how additional tasks added to base case scenarios affected the operators' performance of the main tasks. These additional tasks were in different scenario variants intended to cause high time pressure, high information load, and high masking. The experiment was run in Halden Man-Machine Laboratory's BWR simulator. Seven crews participated, each for one week. There were three operators in each crew. Five main types of scenarios and 20 scenario variants were run. The data from the experiment were analysed by completion time for important actions and by in-depth qualitative analyses of the crews' communications. The results showed that high time pressure decreased some of the crews' performance in the scenarios. When a crew had problems in solving a task for which the time pressure was high, they had even more problems in solving other important tasks. High information load did not affect the operators' performance much and in general the crews were very good at selecting the most important tasks in the scenarios. The scenarios that included both high time pressure and high information load resulted in more reduced performance for the crews compared to the scenarios that only included high time pressure. The total amount of tasks to do and information load to attend to seemed to affect the crews' performance. To solve the scenarios with high time pressure well, it was important to have good communication and good allocation of tasks within the crew. Furthermore, the results showed that scenarios with an added complex, masked task created problems for some crews when solving a relatively simple main task. Overall, the results confirmed that complicating, but secondary tasks, that are not normally taken into account when modelling the primary tasks in a PRA scenario can adversely affect the performance of the main tasks modelled in the PRA scenario. (Author)

Motor-cognitive dual-task performance: effects of a concurrent motor task on distinct components of visual processing capacity.

Science.gov (United States)

Künstler, E C S; Finke, K; Günther, A; Klingner, C; Witte, O; Bublak, P

2018-01-01

Dual tasking, or the simultaneous execution of two continuous tasks, is frequently associated with a performance decline that can be explained within a capacity sharing framework. In this study, we assessed the effects of a concurrent motor task on the efficiency of visual information uptake based on the 'theory of visual attention' (TVA). TVA provides parameter estimates reflecting distinct components of visual processing capacity: perceptual threshold, visual processing speed, and visual short-term memory (VSTM) storage capacity. Moreover, goodness-of-fit values and bootstrapping estimates were derived to test whether the TVA-model is validly applicable also under dual task conditions, and whether the robustness of parameter estimates is comparable in single- and dual-task conditions. 24 subjects of middle to higher age performed a continuous tapping task, and a visual processing task (whole report of briefly presented letter arrays) under both single- and dual-task conditions. Results suggest a decline of both visual processing capacity and VSTM storage capacity under dual-task conditions, while the perceptual threshold remained unaffected by a concurrent motor task. In addition, goodness-of-fit values and bootstrapping estimates support the notion that participants processed the visual task in a qualitatively comparable, although quantitatively less efficient way under dual-task conditions. The results support a capacity sharing account of motor-cognitive dual tasking and suggest that even performing a relatively simple motor task relies on central attentional capacity that is necessary for efficient visual information uptake.

A design space of visualization tasks.

Science.gov (United States)

Schulz, Hans-Jörg; Nocke, Thomas; Heitzler, Magnus; Schumann, Heidrun

2013-12-01

Knowledge about visualization tasks plays an important role in choosing or building suitable visual representations to pursue them. Yet, tasks are a multi-faceted concept and it is thus not surprising that the many existing task taxonomies and models all describe different aspects of tasks, depending on what these task descriptions aim to capture. This results in a clear need to bring these different aspects together under the common hood of a general design space of visualization tasks, which we propose in this paper. Our design space consists of five design dimensions that characterize the main aspects of tasks and that have so far been distributed across different task descriptions. We exemplify its concrete use by applying our design space in the domain of climate impact research. To this end, we propose interfaces to our design space for different user roles (developers, authors, and end users) that allow users of different levels of expertise to work with it.

Contextual control over task-set retrieval.

Science.gov (United States)

Crump, Matthew J C; Logan, Gordon D

2010-11-01

Contextual cues signaling task likelihood or the likelihood of task repetition are known to modulate the size of switch costs. We follow up on the finding by Leboe, Wong, Crump, and Stobbe (2008) that location cues predictive of the proportion of switch or repeat trials modulate switch costs. Their design employed one cue per task, whereas our experiment employed two cues per task, which allowed separate assessment of modulations to the cue-repetition benefit, a measure of lower level cue-encoding processes, and to the task-alternation cost, a measure of higher level processes representing task-set information. We demonstrate that location information predictive of switch proportion modulates performance at the level of task-set representations. Furthermore, we demonstrate that contextual control occurs even when subjects are unaware of the associations between context and switch likelihood. We discuss the notion that contextual information provides rapid, unconscious control over the extent to which prior task-set representations are retrieved in the service of guiding online performance.

Project Tasks in Robotics

DEFF Research Database (Denmark)

Sørensen, Torben; Hansen, Poul Erik

1998-01-01

Description of the compulsary project tasks to be carried out as a part of DTU course 72238 Robotics......Description of the compulsary project tasks to be carried out as a part of DTU course 72238 Robotics...

Age-related decrements in dual-task performance: Comparison of different mobility and cognitive tasks. A cross sectional study.

Science.gov (United States)

Brustio, Paolo Riccardo; Magistro, Daniele; Zecca, Massimiliano; Rabaglietti, Emanuela; Liubicich, Monica Emma

2017-01-01

This cross-sectional study investigated the age-related differences in dual-task performance both in mobility and cognitive tasks and the additive dual-task costs in a sample of older, middle-aged and young adults. 74 older adults (M = 72.63±5.57 years), 58 middle-aged adults (M = 46.69±4.68 years) and 63 young adults (M = 25.34±3.00 years) participated in the study. Participants performed different mobility and subtraction tasks under both single- and dual-task conditions. Linear regressions, repeated-measures and one-way analyses of covariance were used, The results showed: significant effects of the age on the dual and mobility tasks (ptask costs (pperformance under dual-task conditions in all groups (pperformance in the older group (ptask activity affected mobility and cognitive performance, especially in older adults who showed a higher dual-task cost, suggesting that dual-tasks activities are affected by the age and consequently also mobility and cognitive tasks are negatively influenced.

Thoughts in flight: automation use and pilots' task-related and task-unrelated thought.

Science.gov (United States)

Casner, Stephen M; Schooler, Jonathan W

2014-05-01

The objective was to examine the relationship between cockpit automation use and task-related and task-unrelated thought among airline pilots. Studies find that cockpit automation can sometimes relieve pilots of tedious control tasks and afford them more time to think ahead. Paradoxically, automation has also been shown to lead to lesser awareness. These results prompt the question of what pilots think about while using automation. A total of 18 airline pilots flew a Boeing 747-400 simulator while we recorded which of two levels of automation they used. As they worked, pilots were verbally probed about what they were thinking. Pilots were asked to categorize their thoughts as pertaining to (a) a specific task at hand, (b) higher-level flight-related thoughts (e.g.,planning ahead), or (c) thoughts unrelated to the flight. Pilots' performance was also measured. Pilots reported a smaller percentage of task-at-hand thoughts (27% vs. 50%) and a greater percentage of higher-level flight-related thoughts (56% vs. 29%) when using the higher level of automation. However, when all was going according to plan, using either level of automation, pilots also reported a higher percentage of task-unrelated thoughts (21%) than they did when in the midst of an unsuccessful performance (7%). Task-unrelated thoughts peaked at 25% when pilots were not interacting with the automation. Although cockpit automation may provide pilots with more time to think, it may encourage pilots to reinvest only some of this mental free time in thinking flight-related thoughts. This research informs the design of human-automation systems that more meaningfully engage the human operator.

Musical training, bilingualism, and executive function: a closer look at task switching and dual-task performance.

Science.gov (United States)

Moradzadeh, Linda; Blumenthal, Galit; Wiseheart, Melody

2015-07-01

This study investigated whether musical training and bilingualism are associated with enhancements in specific components of executive function, namely, task switching and dual-task performance. Participants (n = 153) belonging to one of four groups (monolingual musician, bilingual musician, bilingual non-musician, or monolingual non-musician) were matched on age and socioeconomic status and administered task switching and dual-task paradigms. Results demonstrated reduced global and local switch costs in musicians compared with non-musicians, suggesting that musical training can contribute to increased efficiency in the ability to shift flexibly between mental sets. On dual-task performance, musicians also outperformed non-musicians. There was neither a cognitive advantage for bilinguals relative to monolinguals, nor an interaction between music and language to suggest additive effects of both types of experience. These findings demonstrate that long-term musical training is associated with improvements in task switching and dual-task performance. Copyright © 2014 Cognitive Science Society, Inc.

Overview of NTCIR-12 Lifelog Task

OpenAIRE

Gurrin, Cathal; Joho, Hideo; Hopfgartner, Frank; Zhou, Liting; Albatal, Rami

2016-01-01

In this paper we review the NTCIR12-Lifelog pilot task,\\ud which ran at NTCIR-12. We outline the test collection employed,\\ud along with the tasks, the eight submissions and the\\ud findings from this pilot task. We finish by suggesting future\\ud plans for the task.

A Comparative Study of Task-based vs. Task- supported Teaching Approaches in an EFL Context

Directory of Open Access Journals (Sweden)

Mahdieh Shafipoor

2015-09-01

Full Text Available In spite of the numerous merits of task-based language instruction as claimed by its supporters in the last few decades, task-supported teaching approach as an alternative was introduced. Since then, there have been controversial debates over the superiority of each of these two approaches. Thus, in the current research project, the purpose was to consider these two teaching approaches in the scope of English language teaching, with the purpose of exploring the most efficient one in an Iranian EFL context. To this end, 120 sophomore students, majoring in English language translation course at Islamic Azad University, Shar-e-Qods branch were selected among 4 intact reading comprehension II classes. Next, they were divided into two experimental groups. The first experimental group received task-based instruction and for the second experimental group, task-trusted teaching approach was applied. The results of the data analyses turned out that task-trusted teaching approach was superior to task-based teaching in teaching reading to EFL learners.

Balancing the Demands of Two Tasks: An Investigation of Cognitive-Motor Dual-Tasking in Relapsing Remitting Multiple Sclerosis.

Science.gov (United States)

Butchard-MacDonald, Emma; Paul, Lorna; Evans, Jonathan J

2018-03-01

People with relapsing remitting multiple sclerosis (PwRRMS) suffer disproportionate decrements in gait under dual-task conditions, when walking and a cognitive task are combined. There has been much less investigation of the impact of cognitive demands on balance. This study investigated whether: (1) PwRRMS show disproportionate decrements in postural stability under dual-task conditions compared to healthy controls, and (2) dual-task decrements are associated with everyday dual-tasking difficulties. The impact of mood, fatigue, and disease severity on dual-tasking was also examined. A total of 34 PwRRMS and 34 matched controls completed cognitive (digit span) and balance (movement of center of pressure on Biosway on stable and unstable surfaces) tasks under single- and dual-task conditions. Everyday dual-tasking was measured using the Dual-Tasking Questionnaire. Mood was measured by the Hospital Anxiety & Depression Scale. Fatigue was measured via the Modified Fatigue Index Scale. No differences in age, gender, years of education, estimated pre-morbid IQ, or baseline digit span between groups. Compared with controls, PwRRMS showed significantly greater decrement in postural stability under dual-task conditions on an unstable surface (p=.007), but not a stable surface (p=.679). Balance decrement scores were not correlated with everyday dual-tasking difficulties or fatigue. Stable surface balance decrement scores were significantly associated with levels of anxiety (rho=0.527; p=.001) and depression (rho=0.451; p=.007). RRMS causes dual-tasking difficulties, impacting balance under challenging conditions, which may contribute to increased risk of gait difficulties and falls. The relationship between anxiety/depression and dual-task decrement suggests that emotional factors may be contributing to dual-task difficulties. (JINS, 2018, 24, 247-258).

Structural basis for Marburg virus VP35-mediated immune evasion mechanisms

Energy Technology Data Exchange (ETDEWEB)

Ramanan, Parameshwaran; Edwards, Megan R.; Shabman, Reed S.; Leung, Daisy W.; Endlich-Frazier, Ariel C.; Borek, Dominika M.; Otwinowski, Zbyszek; Liu, Gai; Huh, Juyoung; Basler, Christopher F.; Amarasinghe, Gaya K. [Sinai; (WU-MED); (UTSMC)

2013-07-22

Filoviruses, marburgvirus (MARV) and ebolavirus (EBOV), are causative agents of highly lethal hemorrhagic fever in humans. MARV and EBOV share a common genome organization but show important differences in replication complex formation, cell entry, host tropism, transcriptional regulation, and immune evasion. Multifunctional filoviral viral protein (VP) 35 proteins inhibit innate immune responses. Recent studies suggest double-stranded (ds)RNA sequestration is a potential mechanism that allows EBOV VP35 to antagonize retinoic-acid inducible gene-I (RIG-I) like receptors (RLRs) that are activated by viral pathogen–associated molecular patterns (PAMPs), such as double-strandedness and dsRNA blunt ends. Here, we show that MARV VP35 can inhibit IFN production at multiple steps in the signaling pathways downstream of RLRs. The crystal structure of MARV VP35 IID in complex with 18-bp dsRNA reveals that despite the similar protein fold as EBOV VP35 IID, MARV VP35 IID interacts with the dsRNA backbone and not with blunt ends. Functional studies show that MARV VP35 can inhibit dsRNA-dependent RLR activation and interferon (IFN) regulatory factor 3 (IRF3) phosphorylation by IFN kinases TRAF family member-associated NFkb activator (TANK) binding kinase-1 (TBK-1) and IFN kB kinase e (IKKe) in cell-based studies. We also show that MARV VP35 can only inhibit RIG-I and melanoma differentiation associated gene 5 (MDA5) activation by double strandedness of RNA PAMPs (coating backbone) but is unable to inhibit activation of RLRs by dsRNA blunt ends (end capping). In contrast, EBOV VP35 can inhibit activation by both PAMPs. Insights on differential PAMP recognition and inhibition of IFN induction by a similar filoviral VP35 fold, as shown here, reveal the structural and functional plasticity of a highly conserved virulence factor.

Survival Processing and the Stroop Task

OpenAIRE

Stephanie A. Kazanas; Kendra M. Van Valkenburg; Jeanette Altarriba

2015-01-01

This study was designed to investigate the impact of survival processing with a novel task for this paradigm: the Stroop color-naming task. As the literature is mixed with regard to task generalizability, with survival processing promoting better memory for words, but not better memory for faces or paired associates, these types of task investigations are important to a growing field of research. Using the Stroop task provides a unique contribution, as identifying items by color is an importa...

Task conflict in the Stroop task: When Stroop interference decreases as Stroop facilitation increases in a low task conflict context

Directory of Open Access Journals (Sweden)

Benjamin Andrew Parris

2014-10-01

Full Text Available In the present study participants completed two blocks of the Stroop task, one in which the Response-Stimulus Interval (RSI was 3500ms and one in which RSI was 200ms. It was expected that, in line with previous research, the shorter RSI would induce a low Task Conflict context by increasing focus on the colour identification goal in the Stroop task. Based on previous research showing the role of Task Conflict in the presence or absence Stroop facilitation, this was expected to lead to the novel finding of an increase in facilitation and simultaneous decrease in interference. Such a finding would be problematic for models of Stroop effects that predict these indices of performance should be affected in tandem. A crossover interaction is reported supporting these predictions. As predicted, the shorter RSI resulted in incongruent and congruent trial RTs decreasing relative to a static neutral baseline condition; hence interference decreased as facilitation increased. An explanatory model (expanding on the work of Goldfarb, Henik and colleagues is presented that: 1 Shows how under certain conditions the predictions from single mechanism models hold true (i.e. when Task conflict is held constant; 2 Shows how it is possible that interference can be affected by an experimental manipulation that leaves facilitation apparently untouched and; 3 Predicts that facilitation cannot be independently affected by an experimental manipulation.

Two different mechanisms associated with ripple-like oscillations (100-250 Hz) in the human epileptic subiculum in vitro

Science.gov (United States)

Alvarado-Rojas, C; Huberfeld, G; Baulac, M; Clemenceau, S; Charpier, S; Miles, R; Menendez de la Prida, L; Le Van Quyen, M

2015-01-01

Transient high-frequency oscillations (150-600 Hz) in local field potential generated by human hippocampal and parahippocampal areas have been related to both physiological and pathological processes. The cellular basis and effects of normal and abnormal forms of high-frequency oscillations (HFO) has been controversial. Here, we searched for HFOs in slices of the subiculum prepared from human hippocampal tissue resected for treatment of pharmacoresistant epilepsy. HFOs occurred spontaneously in extracellular field potentials during interictal discharges (IID) and also during pharmacologically induced preictal discharges (PID) preceding ictal-like events. While most of these events might be considered pathological since they invaded the fast ripple band (>250 Hz), others were spectrally similar to physiological ripples (150-250 Hz). Do similar cellular mechanisms underly IID-ripples and PID-ripples? Are ripple-like oscillations a valid proxy of epileptogenesis in human TLE? With combined intra- or juxta-cellular and extracellular recordings, we showed that, despite overlapping spectral components, ripple-like IID and PID oscillations were associated with different cellular and synaptic mechanisms. IID-ripples were associated with rhythmic GABAergic and glutamatergic synaptic potentials with moderate neuronal firing. In contrast, PID-ripples were associated with depolarizing synaptic inputs frequently reaching the threshold for bursting in most cells. Thus ripple-like oscillations (100-250 Hz) in the human epileptic hippocampus are associated with different mechanisms for synchrony reflecting distinct dynamic changes in inhibition and excitation during interictal and pre-ictal states. PMID:25448920

Selecting Learning Tasks: Effects of Adaptation and Shared Control on Learning Efficiency and Task Involvement

Science.gov (United States)

Corbalan, Gemma; Kester, Liesbeth; van Merrienboer, Jeroen J. G.

2008-01-01

Complex skill acquisition by performing authentic learning tasks is constrained by limited working memory capacity [Baddeley, A. D. (1992). Working memory. "Science, 255", 556-559]. To prevent cognitive overload, task difficulty and support of each newly selected learning task can be adapted to the learner's competence level and perceived task…

Partitioning the Metabolic Cost of Human Running: A Task-by-Task Approach

Science.gov (United States)

Arellano, Christopher J.; Kram, Rodger

2014-01-01

Compared with other species, humans can be very tractable and thus an ideal “model system” for investigating the metabolic cost of locomotion. Here, we review the biomechanical basis for the metabolic cost of running. Running has been historically modeled as a simple spring-mass system whereby the leg acts as a linear spring, storing, and returning elastic potential energy during stance. However, if running can be modeled as a simple spring-mass system with the underlying assumption of perfect elastic energy storage and return, why does running incur a metabolic cost at all? In 1980, Taylor et al. proposed the “cost of generating force” hypothesis, which was based on the idea that elastic structures allow the muscles to transform metabolic energy into force, and not necessarily mechanical work. In 1990, Kram and Taylor then provided a more explicit and quantitative explanation by demonstrating that the rate of metabolic energy consumption is proportional to body weight and inversely proportional to the time of foot-ground contact for a variety of animals ranging in size and running speed. With a focus on humans, Kram and his colleagues then adopted a task-by-task approach and initially found that the metabolic cost of running could be “individually” partitioned into body weight support (74%), propulsion (37%), and leg-swing (20%). Summing all these biomechanical tasks leads to a paradoxical overestimation of 131%. To further elucidate the possible interactions between these tasks, later studies quantified the reductions in metabolic cost in response to synergistic combinations of body weight support, aiding horizontal forces, and leg-swing-assist forces. This synergistic approach revealed that the interactive nature of body weight support and forward propulsion comprises ∼80% of the net metabolic cost of running. The task of leg-swing at most comprises ∼7% of the net metabolic cost of running and is independent of body weight support and forward

The Effect of "Massed" Task Repetitions on Complexity, Accuracy and Fluency: Does It Transfer to a New Task?

Science.gov (United States)

Ahmadian, Mohammad Javad

2011-01-01

To date, research results suggest that task repetition positively affects oral task performance. However, researchers have not yet shown the extension of the benefits of repeating the same task to performance of a new task. This article first provides an overview of the currently available research findings on task repetition and then presents the…

Not all choices are created equal: Task-relevant choices enhance motor learning compared to task-irrelevant choices.

Science.gov (United States)

Carter, Michael J; Ste-Marie, Diane M

2017-12-01

Lewthwaite et al. (2015) reported that the learning benefits of exercising choice (i.e., their self-controlled condition) are not restricted to task-relevant features (e.g., feedback). They found that choosing one's golf ball color (Exp. 1) or choosing which of two tasks to perform at a later time plus which of two artworks to hang (Exp. 2) resulted in better retention than did being denied these same choices (i.e., yoked condition). The researchers concluded that the learning benefits derived from choice, whether irrelevant or relevant to the to-be-learned task, are predominantly motivational because choice is intrinsically rewarding and satisfies basic psychological needs. However, the absence of a group that made task-relevant choices and the lack of psychological measures significantly weakened their conclusions. Here, we investigated how task-relevant and task-irrelevant choices affect motor-skill learning. Participants practiced a spatiotemporal motor task in either a task-relevant group (choice over feedback schedule), a task-irrelevant group (choice over the color of an arm-wrap plus game selection), or a no-choice group. The results showed significantly greater learning in the task-relevant group than in both the task-irrelevant and no-choice groups, who did not differ significantly. Critically, these learning differences were not attributed to differences in perceptions of competence or autonomy, but instead to superior error-estimation abilities. These results challenge the perspective that motivational influences are the root cause of self-controlled learning advantages. Instead, the findings add to the growing evidence highlighting that the informational value gained from task-relevant choices makes a greater relative contribution to these advantages than motivational influences do.

The Role of Task Complexity, Modality, and Aptitude in Narrative Task Performance

Science.gov (United States)

Kormos, Judit; Trebits, Anna

2012-01-01

The study reported in this paper investigated the relationship between components of aptitude and the fluency, lexical variety, syntactic complexity, and accuracy of performance in two types of written and spoken narrative tasks. We also addressed the question of how narrative performance varies in tasks of different cognitive complexity in the…

Respiratory sinus arrhythmia responses to cognitive tasks: effects of task factors and RSA indices.

Science.gov (United States)

Overbeek, Thérèse J M; van Boxtel, Anton; Westerink, Joyce H D M

2014-05-01

Many studies show that respiratory sinus arrhythmia (RSA) decreases while performing cognitive tasks. However, there is uncertainty about the role of contaminating factors such as physical activity and stress-inducing task variables. Different methods to quantify RSA may also contribute to variable results. In 83 healthy subjects, we studied RSA responses to a working memory task requiring varying levels of cognitive control and a perceptual attention task not requiring strong cognitive control. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean interbeat interval and respiration rate, resulting in eight different RSA indices. The two tasks were clearly differentiated by heart rate and facial EMG reference measures. Cognitive control induced inhibition of RSA whereas perceptual attention generally did not. However, the results show several differences between different RSA indices, emphasizing the importance of methodological variables. Age and sex did not influence the results. Copyright © 2014 Elsevier B.V. All rights reserved.

Video game practice optimizes executive control skills in dual-task and task switching situations.

Science.gov (United States)

Strobach, Tilo; Frensch, Peter A; Schubert, Torsten

2012-05-01

We examined the relation of action video game practice and the optimization of executive control skills that are needed to coordinate two different tasks. As action video games are similar to real life situations and complex in nature, and include numerous concurrent actions, they may generate an ideal environment for practicing these skills (Green & Bavelier, 2008). For two types of experimental paradigms, dual-task and task switching respectively; we obtained performance advantages for experienced video gamers compared to non-gamers in situations in which two different tasks were processed simultaneously or sequentially. This advantage was absent in single-task situations. These findings indicate optimized executive control skills in video gamers. Similar findings in non-gamers after 15 h of action video game practice when compared to non-gamers with practice on a puzzle game clarified the causal relation between video game practice and the optimization of executive control skills. Copyright © 2012 Elsevier B.V. All rights reserved.

JV Task 90 - Activated Carbon Production from North Dakota Lignite

Energy Technology Data Exchange (ETDEWEB)

Steven Benson; Charlene Crocker; Rokan Zaman; Mark Musich; Edwin Olson

2008-03-31

The Energy & Environmental Research Center (EERC) has pursued a research program for producing activated carbon from North Dakota lignite that can be competitive with commercial-grade activated carbon. As part of this effort, small-scale production of activated carbon was produced from Fort Union lignite. A conceptual design of a commercial activated carbon production plant was drawn, and a market assessment was performed to determine likely revenue streams for the produced carbon. Activated carbon was produced from lignite coal in both laboratory-scale fixed-bed reactors and in a small pilot-scale rotary kiln. The EERC was successfully able to upgrade the laboratory-scale activated carbon production system to a pilot-scale rotary kiln system. The activated carbon produced from North Dakota lignite was superior to commercial grade DARCO{reg_sign} FGD and Rheinbraun's HOK activated coke product with respect to iodine number. The iodine number of North Dakota lignite-derived activated carbon was between 600 and 800 mg I{sub 2}/g, whereas the iodine number of DARCO FGD was between 500 and 600 mg I{sub 2}/g, and the iodine number of Rheinbraun's HOK activated coke product was around 275 mg I{sub 2}/g. The EERC performed both bench-scale and pilot-scale mercury capture tests using the activated carbon made under various optimization process conditions. For comparison, the mercury capture capability of commercial DARCO FGD was also tested. The lab-scale apparatus is a thin fixed-bed mercury-screening system, which has been used by the EERC for many mercury capture screen tests. The pilot-scale systems included two combustion units, both equipped with an electrostatic precipitator (ESP). Activated carbons were also tested in a slipstream baghouse at a Texas power plant. The results indicated that the activated carbon produced from North Dakota lignite coal is capable of removing mercury from flue gas. The tests showed that activated carbon with the greatest

Task-oriented maximally entangled states

International Nuclear Information System (INIS)

Agrawal, Pankaj; Pradhan, B

2010-01-01

We introduce the notion of a task-oriented maximally entangled state (TMES). This notion depends on the task for which a quantum state is used as the resource. TMESs are the states that can be used to carry out the task maximally. This concept may be more useful than that of a general maximally entangled state in the case of a multipartite system. We illustrate this idea by giving an operational definition of maximally entangled states on the basis of communication tasks of teleportation and superdense coding. We also give examples and a procedure to obtain such TMESs for n-qubit systems.

Appraisal, Coping, Task Performance, and Cardiovascular Responses during the Evaluated Speaking Task.

Science.gov (United States)

Baggett, H. Lane; And Others

1996-01-01

Appraisal, coping, task performance, and cardiovascular responses were examined among men high and low in speech anxiety who prepared and performed a speech under evaluative conditions. Speech-anxious men saw the task as more threatening. They were more stressed, anxious, distracted, and aware of their emotions, focused on the passage of time, and…