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111.
Terry Huntsberger 《Autonomous Robots》2001,11(3):341-346
Robotic missions beyond 2013 will likely be precursors to a manned habitat deployment on Mars. Such missions require robust control systems for long duration activities. Current single rover missions will evolve into deployment of multiple, heterogeneous cooperating robotic colonies. This paper describes the map-making memory and action selection mechanism of BISMARC (
iologically
nspired
ystem for
ap-based
utonomous
over
ontrol) that is currently under development at the Jet Propulsion Laboratory in Pasadena, CA (Huntsberger and Rose, Neutral Networks, 11(7/8):1497–1510). BISMARC is an integrated control system for long duration missions involving robots performing cooperative tasks. 相似文献
112.
Common needs and different agendas: How trainee teachers make progress in their ability to use ICT in subject teaching. Some lessons from the UK 总被引:2,自引:0,他引:2
The paper reports on the outcomes of a British Educational Communications and Technology Agency (BECTa) funded study which explored the views of teacher trainees and their mentors in two different school subjects on what strategies, interventions and resources had a positive impact on their ability to use ICT effectively in their subject teaching.The research aimed to explore both commonalities in trainees’ views of which strategies and interventions had a positive influence on their ability to use ICT effectively in subject teaching, and subject discipline dimensions of ICT use, i.e. the ways in which training needs might vary between trainees in different school subjects.The study focused on the views of two successive cohorts of science and history trainees (133 trainees in all), and 21 of their supervising mentors. The outcomes showed that some important determinants of progression in the ability to deploy ICT confidently and effectively in subject teaching were common to both subject groups, but that there were differing views on which ICT applications offered most potential for enhancing teaching and learning in their subject and differences in their preferred priorities for investment in ICT. The study also revealed that trainees felt that many of the experiences and resources which they had encountered in the course of their training had not been helpful.A follow up survey was undertaken of 114 trainees across six subject areas to further explore some of the findings from the initial survey. The concluding section of the paper suggests ways in which trainee teachers might be prepared more effectively for using ICT in their subject teaching. 相似文献
113.
Anderson Ursula S.; Stoinski Tara S.; Bloomsmith Mollie A.; Maple Terry L. 《Canadian Metallurgical Quarterly》2007,121(1):1
The ability to select the larger of two quantities ranging from 1 to 5 (relative numerousness judgment [RNJ[) and the ability to select the larger of two pairs of quantities with each pair ranging from 1 to 8 (summation) were evaluated in young, middle-aged, and older adult orangutans (7 Pongo pygmaeus abelii and 2 Pongo pygmaeus pygmaeus). Summation accuracy and RNJ were similar to those of previous reports in apes; however, the pattern of age-related differences with regard to these tasks was different from that previously reported in gorillas. Older orangutans were less accurate than the young and middle-aged for RNJ, and summation accuracy was equivalent among age groups. Evidence was found to suggest that the young and middle-aged based their selection of the largest quantity pair on both quantities within each pair during the summation task. These results show a relationship between subject age and the quantitative abilities of adult orangutans. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
We introduce a rule-based approach for learning and recognition of complex actions in terms of spatio-temporal attributes of primitive event sequences. During learning, spatio-temporal decision trees are generated which satisfy relational constraints of the training data. The resulting rules are used to classify new dynamic pattern fragments, and general heuristic rules are used to combine classification evidences of different pattern fragments. 相似文献
115.
George A Manganaris Vlasios Goulas Ariel R Vicente Leon A Terry 《Journal of the science of food and agriculture》2014,94(5):825-833
Small berry fruits are consumed because of their attractive colour and special taste, and are considered one of the richest sources of natural antioxidants. Their consumption has been linked to the prevention of some chronic and degenerative diseases. The term ‘berry fruits’ encompasses the so‐called ‘soft fruits’, primarily strawberry, currants, gooseberry, blackberry, raspberry, blueberry and cranberry. The objective of this review is to highlight the nutraceutical value of berries and to summarize the factors affecting berry fruit antioxidants. Particular attention is given to postharvest and processing operation factors that may affect fruit phytochemical content. The structure–antioxidant relationships for phenolic compounds – the main group of antioxidants in this fruit group – are presented and major areas for future research are identified. © 2013 Society of Chemical Industry 相似文献
116.
Continuing research at Langley Research Center on the synthesis and development of new inexpensive flexible aromatic polyimides as adhesives has resulted in a material identified as LARC-F-SO2 with similarities to polyimidesulfone (PISO2) and other flexible backbone polyimides recently reported by Progar and St. Clair. Also prepared and evaluated was an endcapped version of PISO2. These two polymers were compared with LARC-TPI and LARC-STPI, polyimides researched in our laboratory and reported in the literature. The adhesive evaluation, primarily based on lap shear strength (LSS) tests, involved preparing adhesive tapes, conducting bonding studies and exposing lap shear specimens to 204°C air for up to 1000 hrs and to a 72-hour water boil. LSS tests at RT, 177°C and 204°C were performed before (controls) and after these exposures. The type of adhesive failure as well as the Tg was determined for the fractured specimens. The results indicate that LARC-TPI provides the highest LSSs, 33 MPa at RT, 30 MPa at 177°C, and 26 MPa at 204°C. LARC-F-SO2, LARC-TPI and LARC-STPI all retain their strengths after thermal exposure for 1000 hrs and PISO2 retains greater than 80% of its control strengths. Most of the four adhesive systems showed reduced strengths for all test temperatures although they still retained a high percentage of their original strength (<60%) except for one case. The predominant failure mode was cohesive with no significant change in the Tgs. Although the LARC-F-SO2 could not be prepared in diglyme alone as the solvent, the properties of the resulting adhesive were notable. The darkening of the adhesive during bonding was typical of systems which utilize amide solvents. 相似文献
117.
118.
Introduces the new Student Editorial Board for School Psychology Quarterly. Along with the Research Design and Methodology Section and the Book Review Section, which made their inaugural appearance in the Winter 1998 issue, the Student Editorial Board is intended to strengthen both our journal and our field as we move into the next century. It is expected that the Student Editorial Board will result in symbiotic benefits for both our field and the board members themselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
120.
Stout Julie C.; Bondi Mark W.; Jernigan Terry L.; Archibald Sarah L.; Delis Dean C.; Salmon David P. 《Canadian Metallurgical Quarterly》1999,13(2):188
Twenty-seven research participants with dementia of the Alzheimer type were studied with the California Verbal Learning Test (D. C. Delis, J. H. Kramer, E. Kaplan, & B. A. Ober, 1987) and standardized volume measures of the mesial temporal cortical gray matter, neocortical gray matter, thalamus, and caudate nuclei, from magnetic resonance imaging. A pattern of atrophic brain changes in the mesial temporal lobes (MTL) and the thalamus, with relatively less severe atrophy in the neocortical gray matter, was associated with poorer learning of the word list. Similar patterns of brain atrophy were observed for measures of delayed recall and recognition hits. However, for delayed recall, neither contribution was statistically significant, and for recognition hits, MTL was only at the trend level for significance. These results provide evidence that the verbal memory deficit of Alzheimer's disease (AD) is associated not only with the mesial temporal limbic cortex, thought to be the site of earliest and most severe pathology in AD, but also with damage in the thalamus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献