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Richard Laing† 《控制论与系统》2013,44(2):16-25
Abstract A species of artificial organism in which individuals consist of freely interacting elementary components enclosed in an expandible envelope is described. Some organisms of this species are shown to be universal instruction-obeying mechanisms. Several procedures by which such artificial organisms might reproduce are presented and discussed. 相似文献
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Abstract A preliminary investigation of the role of look-ahead in one-person games is presented. The use of look-ahead in comparing the effectiveness of different heuristic functions is discussed. There is a survey of recent work in tree-searching including that of Doran and Michie [4], Hart, Nilsson, and Raphael [7] and Pohl [17]–[19]. Based on some of Pohl's results, two theorems are proven in Section 2. These suggest a possible use for look-ahead. Some experimental results are presented in Section 3 which satisfy to a limited degree the aforementioned theorems, and some additional observations are made. In conclusion, an attempt is presented to relate look-ahead to the notion of “informedness” introduced by Hart, Nilsson, and Raphael. Finally, some further directions for research are suggested. 相似文献
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Tuning in to psychological change: Linguistic markers of psychological traits and emotions over time in popular U.S. song lyrics. 总被引:1,自引:0,他引:1
DeWall C. Nathan; Pond Richard S. Jr.; Campbell W. Keith; Twenge Jean M. 《Canadian Metallurgical Quarterly》2011,5(3):200
American culture is filled with cultural products. Yet few studies have investigated how changes in cultural products correspond to changes in psychological traits and emotions. The current research fills this gap by testing the hypothesis that one cultural product—word use in popular song lyrics—changes over time in harmony with cultural changes in individualistic traits. Linguistic analyses of the most popular songs from 1980–2007 demonstrated changes in word use that mirror psychological change. Over time, use of words related to self-focus and antisocial behavior increased, whereas words related to other-focus, social interactions, and positive emotion decreased. These findings offer novel evidence regarding the need to investigate how changes in the tangible artifacts of the sociocultural environment can provide a window into understanding cultural changes in psychological processes. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Donglai Lu Jun Wang Limin Wang Dan Du Charles Timchalk Richard Barry Yuehe Lin 《Advanced functional materials》2011,21(22):4371-4378
A novel disposable electrochemical immunosensor for highly selective and sensitive detection of organophosphorylated butyrylcholinesterase (OP‐BChE), a specific biomarker for exposure to toxic organophosphorus agents, is presented. In this new approach, zirconia nanoparticles (ZrO2) were employed to selectively capture the OP moiety of OP‐BChE adducts, followed by quantum dot (QD)‐tagged anti‐BChE antibodies for amplified quantification. The captured CdSe‐QD tags can be sensitively detected by stripping voltammetry using an in situ bismuth‐plating method. The OP agent, diisopropylfluorophosphate (DFP), was selected to prepare OP‐BChE adducts in various matrices. The formation of OP‐BChE adducts in plasma sample was confirmed using mass spectroscopy. The developed electrochemical immunosensor demonstrates a highly linear voltammetric response over the range of 0.1 to 30 nM OP‐BChE, with a detection limit of 0.03 nM (based on signal/noise = 3), coupled with a good reproducibility (relative standard deviation 4.5%). Moreover, the immunosensor has been validated with biomonitoring of OP‐BChE adducts in the plasma samples. This novel nanoparticle‐based electrochemical immunosensor thus provides an alternative way for designing a sensitive and cost‐effective sensing platform for on‐site screening/evaluating exposure to a variety of OP agents. 相似文献