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排序方式: 共有832条查询结果,搜索用时 31 毫秒
31.
Nick Gravish Mateo Garcia Nicole Mazouchova Laura Levy Paul B. Umbanhowar Michael A. D. Goodisman Daniel I. Goldman 《Journal of the Royal Society Interface》2012,9(77):3312-3322
Social insects work together to complete tasks. However, different individuals within a colony may vary in task proficiency. We investigated if fire ant (Solenopsis invicta) worker body size influenced the ability to construct tunnels—a key component of subterranean nests. We monitored excavation by worker groups in a substrate of small wetted glass particles in quasi-two-dimensional arenas. Morphological and network features of the tunnel system were measured. Total tunnel area did not differ significantly between groups of large and small workers, although the tunnel area of control sized workers was significantly larger than that of large workers. Moreover, large workers created wider but shorter tunnels, with slower growth rate of tunnel number. However, edge–vertex scaling and degree distribution of the tunnel network were similar across all treatments. In all cases, the amount of excavated material was correlated with the number of active workers. Our study reveals that morphological features of excavated tunnels show modest variation when constructed by workers of varying sizes, but topological features associated with the tunnel network are conserved. These results suggest that important behavioural aspects of tunnel construction—and thus nest building—are similar among morphologically distinct members of fire ant societies. 相似文献
32.
Degani Asaf Goldman Claudia V. Deutsch Omer Tsimhoni Omer 《Cognition, Technology & Work》2017,19(2-3):211-231
Cognition, Technology & Work - This paper presents an approach to human–machine interactions based on the concept of teamwork and the psychological theory of object relations. We envision... 相似文献
33.
John N. Morris Elizabeth P. Howard Brant E. Fries Randi Berkowitz Beryl Goldman Daniel David 《Accident; analysis and prevention》2014
This project used the interRAI based, community health assessment (CHA) to develop a model for identifying current elder drivers whose driving behavior should be reviewed. The assessments were completed by independent housing sites in COLLAGE, a non-profit, national senior housing consortium. Secondary analysis of data drawn from older adults in COLLAGE sites in the United States was conducted using a baseline assessment with 8042 subjects and an annual follow-up assessment with 3840 subjects. Logistic regression was used to develop a Driving Review Index (DRI) based on the most useful items from among the many measures available in the CHA assessment. Thirteen items were identified by the logistic regression to predict drivers whose driving behavior was questioned by others. In particular, three variables reference compromised decision-making abilities: general daily decisions, a recent decline in ability to make daily decisions, and ability to manage medications. Two additional measures assess cognitive status: short-term memory problem and a diagnosis of non-Alzheimers dementia. Functional measures reflect restrictions and general frailty, including receiving help in transportation, use of a locomotion appliance, having an unsteady gait, fatigue, and not going out on most days. The final three clinical measures reflect compromised vision, little interest or pleasure in things normally enjoyed, and diarrhea. The DRI focuses the review process on drivers with multiple cognitive and functional problems, including a significant segment of potentially troubled drivers who had not yet been publicly identified by others. There is a need for simple and quickly identified screening tools to identify those older adults whose driving should be reviewed. The DRI, based on the interRAI CHA, fills this void. Assessment at the individual level needs to be part of the backdrop of science as society seeks to target policy to identify high risk drivers instead of simply age-based testing. 相似文献
34.
Recent conceptualizations of alcohol expectancies relate cognitive schemas to their neurobiological underpinnings; cue reactivity paradigms lend themselves well to testing this broadened conceptual framework. In the present study, we examined the relationship between self-reported alcohol expectancies and responses to alcohol-related and affective picture cues among fifty-five young adults. In addition to traditional subjective and psychophysiological indices of cue reactivity, the startle eyeblink reflex was obtained during picture cue presentations to address both attention-arousal (early probes) and affective-motivational (late probes) aspects of cue processing. Analyses indicated that participants reporting greater positive, arousing, and social alcohol expectancies rated alcohol cues as more pleasant, arousing, and craving-inducing. In addition, participants displayed inhibited startle reactivity to late alcohol cue probes, indicative of an appetitive reaction. Finally, startle responding to early probes indicated that participants with greater alcohol expectancies displayed blunted attention to negative affect cues. Findings are discussed in terms of the utility of the startle reflex and cue reactivity paradigms for clarifying the relationship between alcohol expectancies and motivated attention to salient cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
This study presents a novel application of marine geoelectromagnetic technique, in an attempt to delineate freshwater extension of the coastal sub-aquifers beneath the SE Mediterranean Sea, along central Israel. The novel marine Ex-Bz time domain electromagnetic (TDEM) geophysical method was applied, demonstrating high sensitivity to the presence of sub-seafloor electrically resistive structures up to several kilometers offshore (shallow marine environment). The study included 19 marine measurements located offshore between Ashdod in the south to Tel-Aviv in the north, where a previous onshore study detected fresh groundwater below seawater intrusion at the coast line. The offshore measurements were conducted to distances of up to 3 km from the shoreline. It was found that the lower sub-aquifer contains fresh groundwater (resistivity >10 Ω-m) to a distance of 2.8 km offshore along the 30 km strip, and is probably constrained by lateral geo-facial changes. 相似文献
36.
37.
Constraints and AI planning 总被引:1,自引:0,他引:1
Nareyek A. Freuder E.C. Fourer R. Giunchiglia E. Goldman R.P. Kautz H. Rintanen J. Tate A. 《Intelligent Systems, IEEE》2005,20(2):62-72
Tackling real-world planning problems often requires considering various types of constraints, which can range from simple numerical comparators to complex resources. This article provides an overview of techniques to deal with such constraints by expressing planning within general constraint-solving frameworks. Our goal here is to explore the interplay of constraints and planning, highlighting the differences between propositional satisfiability (SAT), integer programming (IP), and constraint programming (CP), and discuss their potential in expressing and solving AI planning problems. 相似文献
38.
Jerry Goldman Steve Renals Steven Bird Franciska de Jong Marcello Federico Carl Fleischhauer Mark Kornbluh Lori Lamel Douglas W. Oard Claire Stewart Richard Wright 《International Journal on Digital Libraries》2005,5(4):287-298
Spoken-word audio collections cover many domains, including radio and television broadcasts, oral narratives, governmental proceedings, lectures, and telephone conversations. The collection, access, and preservation of such data is stimulated by political, economic, cultural, and educational needs. This paper outlines the major issues in the field, reviews the current state of technology, examines the rapidly changing policy issues relating to privacy and copyright, and presents issues relating to the collection and preservation of spoken audio content . 相似文献
39.
40.
Goldman C.V. Rosenschein J.S. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2002,32(1):135-148
Problems approached by multi-agent systems are typically complex. It is usually difficult to know at system design stage how many agents need to be in the system, what each agent's role is, and how the agents should interact to get optimal performance out of the group. The aim of the testbed presented here is to investigate which kinds of multi-agent systems could be developed to solve ranges of problems, avoiding the need to reorganize the agents from scratch for each task. The agent organization process explored here is based on the agents' knowledge, and not on their tasks. This opens up a new approach for distributed artificial intelligence designers to have their domain organized before the allocation of tasks among agents. These kinds of organizations should be more robust for solving different problems related to the same knowledge. We define information oriented domains for that purpose. An evolutionary approach to the design of a multi-agent system is suggested. Our model is based on a cellular automaton whose rules of dynamics induce the formation of an organization of agents. Patterns of organization obtained empirically are presented. Our knowledge-based organization approach is analyzed both from theoretical and practical perspectives 相似文献