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641.
Partnership between a person and a robot could be simplified if the robot were intelligent enough to understand human intentions and perform accordingly. During the last decade, we have been developing such an intelligent robot called ISAC. Originally, ISAC was designed to assist the physically disabled, but gradually became a test bed for more robust human–robot teaming (see http://eecs.vanderbilt.edu/CIS/). In this paper, we will describe a framework for human–robot interaction, a multi-agent based robot control architecture, and short- and long-term memory structures for the robot brain. Two applications will illustrate how ISAC interacts with the human.  相似文献   
642.
“If a tree falls in the forest and no one is around to hear it, does it make a sound?” and, paraphrasing the proverbial philosophy question, if a company has a strong CSR commitment but nobody recognizes it, does it produce any benefits? Business returns from corporate social responsibility (CSR) practices, such as customers loyalty and company reputation, depend heavily on how stakeholders perceive the company social behavior, making the measure of stakeholder perception a key issue in the process of CSR assessment. In this paper the analysis of CSR activities, as perceived by stakeholders, is realized utilizing global reporting initiative (GRI) indicators structured under balanced scorecard (BSC) perspectives and sustainability dimensions. We utilize a multi-criteria approach combined with fuzzy linguistic variables, in the variation of the 2-tuple, creating a hierarchy of CSR components with the purpose of integrating financial and non-financial sustainability dimensions and strategic perspectives. The hierarchy provides a multidimensional model that allows to evaluate the multifaceted social behavior of a company: the same company can be perceived simultaneously as responsible or irresponsible depending on the considered dimension and perspective.  相似文献   
643.
Powder Metallurgy and Metal Ceramics - It is shown from experimental tests on alloys in the Cr ― Nb ― C system in the region of the (Cr) ― (Nb) ― (NbC) subsystem at the...  相似文献   
644.
Thirty-nine males and 18 females, in six groups, participated in six high altitude treks (each lasting 3–4 weeks and climbing up to 5500 m) in the Himalaya and Karakoram. Inverse relationships between mean overnight total insulation (sleeping bag plus clothing) and air temperature in tents were recorded for all treks. Average overnight thermal sensations varied little with air temperature as the subjects modified their clothing insulation to maintain thermal sensations warmer than ‘neutral’ for all treks. For combined treks, subjects adjusted their mean overnight total insulation up to 7 clo for thermal sensations of between 0 (‘neutral’) and +1 (‘slightly warm’) on average, measured on the standard seven-point thermal sensation scale developed for everyday low-altitude conditions. Very few subjects (3% of all daily responses, on average) reported ‘cool’ or ‘cold’ sensations. General tent discomfort increased with altitude suggesting that subjects interpreted tent comfort predominantly in terms of thermal outdoor conditions.  相似文献   
645.
This paper treats the unfolding problem of estimating the density distribution of particles dispersed in a three-dimensional specimen. A general framework is set in terms of a probabilistic model for the distribution of a discrete number of particle sizes with prescribed shapes which are sampled and observed by processes capable of being modeled. The general formulation allows density estimates and standard deviation estimates for each particle size in the distribution to be made with data from observational processes that may distort or truncate the sampled information. The method is related to the earlier works on unfolding or estimating the density distribution of spherical particles sectioned by planar probes. The method is also used to develop a more accurate estimate for the density distribution of spherical voids where the observational process is the indirect microscopy of a replicated surface.  相似文献   
646.
In this paper, the effect of interaction with the substrate surface on the orientation of films' molecules of substituted liquid crystalline phthalocyanines M(II)Pc (M = Cu, Ni, Zn) having monoazacrown ether moieties on the periphery containing long alkyloxyphenyl N-pivotal groups is studied. The phthalocyanine derivatives demonstrate thermotropic mesophase behaviour and show Colh mesophases over a wide temperature range. The preferential orientation of the phthalocyanine films deposited on glass, silicon and NaCl substrates as well as between two of those substrates is studied by polarized Raman spectroscopy at different temperatures. These phthalocyanines form homeotropically aligned films on the surface of NaCl substrate, whereas planar alignment with a random distribution of the column directors occurs on the glass slides.  相似文献   
647.
    
Sorption and desorption hysteresis of widely applied triazine and phenylurea herbicides were studied for river sediments. Organic carbon normalized sorption coefficient (KOC) values for all herbicides were significantly higher for the sediment from the downstream region of the river vs. the upstream sediment. On the basis of the measured KOC values, the triazine herbicides can be arranged in the following order: terbutryn>terbuthylazine>ametryn>atrazine. Among the phenylurea herbicides, chlorotoluron exhibited higher sorption than isoproturon (KOC values of 137 vs. 60 and 228 vs. 125 L/kg for the upstream and downstream sediments, respectively). Moreover, chlorotoluron exhibited lower desorption potential as compared with isoproturon (apparent hysteresis index values were 0.2–0.3 for chlorotoluron vs. 0.6–0.9 for isoproturon, measured with the upstream sediment). High sorption affinity of chlorotoluron to the sediments is probably due to stronger H-bonding interactions of the herbicide molecules with the sorbents. For both phenylurea herbicides, desorption hysteresis increased with decrease in sorbed amount. This behavior was opposite to the hysteresis trend observed for the triazines. The Cl-triazines (atrazine and terbuthylazine) exhibited higher desorption hysteresis than the S-triazines (ametryn and terbutryn). Therefore, the apparent hysteresis index values calculated for the Cl-triazines were lower than the values of S-triazines (about 0.4 and 0.7, respectively). Based on the relative strength of H-bonding interactions of Cl- and S-triazines with formate anion and on the desorption hysteresis data we suggest a gradient-derived hole-filling sorption mechanism for the triazine herbicides with the river sediments.  相似文献   
648.
649.
Neuropsychological deficits have been reported among trauma survivors with posttraumatic stress disorder (PTSD). It is often assumed that these cognitive difficulties are toxic consequences of trauma exposure. Alternatively, they may reflect preexisting characteristics that contribute to the likelihood of developing PTSD. To address this possibility, the authors evaluated cognitive performance in monozygotic twin pairs who were discordant for combat exposure. Pairs were grouped according to whether the combat-exposed brother developed PTSD. The combat-unexposed cotwins of combat veterans with PTSD largely displayed the same performance as their brothers, which was significantly lower than that of non-PTSD combat veterans and their brothers. The results support the notion that specific domains of cognitive function may serve as premorbid risk or protective factors in PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
650.
This article presents the results of a pilot study of the Marriage Moments program, designed to prevent relationship deterioration during the 1st year of parenthood. The self-guided, low-intensity program emphasizes strengthening marital virtues and partnership during this time of significant personal and family transition. One hundred fifty-five married couples participated in a randomized clinical trial with 2 psychoeducational treatment groups (a self-guided group and an instructor-encouraged group) and a comparable control group. Despite positive formative evaluation results from program participants, hierarchical linear modeling analyses failed to find significant Group × Time differences on spouses' reports of marital virtues and a set of relational outcome measures. This failure reinforces the need for psychoeducators to invest in outcome evaluation research before claiming program success. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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