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141.
Exploring the design space of robots: Children''s perspectives 总被引:2,自引:0,他引:2
Children's perceptions and evaluations of different robot designs are an important unexplored area within robotics research considering that many robots are specifically designed for children. To examine children's feelings and attitudes towards robots, a large sample of children (N = 159) evaluated 40 robot images by completing a questionnaire for each image, which enquired about robot appearance, robot personality dimensions and robot emotions. Results showed that depending on a robot's appearance children clearly distinguished robots in terms of their intentions (i.e. friendly vs. unfriendly), their capability to understand, and their emotional expression. Results of a principal components analysis of the children's ratings of the robots' personality attributes revealed two dimensions labelled ‘Behavioural Intention’ and ‘Emotional Expression’. Robots were classified according to their scores on these two dimensions and a content analysis of their appearance was conducted in an attempt to identify salient features of different robot personalities. Children judged human-like robots as aggressive, but human–machine robots as friendly. Results on children's perceptions of the robots' behavioural intentions provided tentative empirical support for the Uncanny Valley, hypothesized by (Mori, M., 1970), reflecting a situation where robots are very human-like, but still distinguishable from humans, evoking a feeling of discomfort or repulsion. The paper concludes with a discussion of design implications for robots, and the use of robots in educational contexts. 相似文献
142.
Xin Miao Peng Gong Sarah Swope Ruiliang Pu Raymond Carruthers Gerald L. Anderson Jill S. Heaton C.R. Tracy 《Remote sensing of environment》2006,101(3):329-341
The invasive weed yellow starthistle (Centaurea solstitialis) has infested between 4 and 6 million hectares in California. It often forms dense infestations and rapidly depletes soil moisture, preventing the establishment of other species. Precise assessment of its canopy cover, especially low-density abundance in the earlier growing season, is the key to effective management. Compact Airborne Spectrographic Imager 2 (CASI-2) hyperspectral imagery was acquired at the western edge of California's Central Valley grasslands on July 15, 2003. Four linear spectral mixture models (LSMM) were investigated from the original CASI-2 data. Band selections based upon residual analysis and feature extraction (PCA) were further explored to reduce the data dimension. All approaches, except four band-selection unconstrained LSMMs, provide consistent results. The uncertainty of the PCA-based LSMM was estimated through a Monte-Carlo simulation. The maximum standard deviation was approximately 11%. The results suggest that unmixing CASI-2 imagery could be used for estimating and mapping yellow starthistle for larger regional areas. 相似文献
143.
Sarah Stephens Aaron Figg Chris Mann Robert Atkinson Robert Woodrough 《Journal of The Association for Laboratory Automation》2002,7(3):41
Green fluorescent protein (GFP) has many applications as a marker in living cells, and has become widely used as a reporter gene in microbial, plant and animal cells. Screening microbial colonies for GFP expression enables various types of assays (e.g. for secretory mutations). However, this is laborious, non-quantitative and potentially hazardous to the operator (due to UV illumination) when performed manually. In order to address this the GloPix robot was developed. The imaging system discriminates between colonies based on the level of fluorescence activity and the picking function automatically transfers cells to microplate wells. Measuring fluorescent activity allows quantitation of fluorescent tag concentration/expression. 相似文献
144.
This paper contributes to current debates on the psycho-social determinants of health by offering a qualitative analysis of the health consequences of the experience of mortgage possession. Previous research has shown that it is possible to decipher a statistical relationship between the onset of mortgage indebtedness and health. This paper extends this work by examining how this statistical patterning is generated at the level of the 'lived experiences' of families experiencing the loss of their mortgaged home. The narratives of 44 adults and 10 children from a sample of 30 households who have experienced mortgage possession are analysed. The results of this qualitative analysis are related to current debates in both the sociology of health inequalities and the sociology of the emotions concerned with the specification of what Elstad has called "the psychological stress, relative deprivation and psycho-social injuries of inequality structures". 相似文献
145.
JB Van Liew PJ Davis FB Davis LL Bernardis MR Deziel LN Marinucci D Kumar 《Canadian Metallurgical Quarterly》1993,48(5):B184-B190
We studied the relationships of plasma glucose, fructosamine, triglycerides, and cholesterol as a function of age, gender, and diet in barrier-raised Fischer 344 rats aged 5 to 26 months, fed a diet either ad libitum or restricted to 60% of the ad libitum caloric intake. The complex relationships of these plasma levels to age, gender, and diet led to the development of a model with age, diet, and sex as covariates. Overall, fasting plasma glucose concentrations were reduced by approximately 25% in rats on the restricted diet, compared to ad libitum-fed animals. There was a significant age-dependent decline in glucose levels in male animals, whereas in females there was an increase in plasma glucose with aging. Plasma fructosamine levels in calorie-restricted animals, overall, were reduced by 7% compared to levels in animals fed ad libitum. There was a significant positive correlation between plasma glucose and fructosamine levels. Mean plasma triglyceride content was decreased by 50% in calorie-restricted rats compared to ad libitum-fed animals. A significant decrease in triglyceride levels with increasing age was seen in male animals, and an increase with aging in females. There was a significant positive correlation between plasma glucose and triglyceride levels. Plasma cholesterol levels in calorie-restricted animals were reduced by 7% compared to levels in ad libitum-fed animals. An increase of cholesterol concentration with aging was significant in both males and females. Analysis of the data showed that there were significant differences between male and female Fischer 344 rats in the response of plasma glucose and fructosamine to aging and calorie restriction. Changes of plasma triglyceride and cholesterol with aging and dietary calorie restriction were also different in males and females. Studies of the effect of aging on glycemia and blood lipid content should take into account the contributions of animal sex. 相似文献
146.
Investigated how women (aged 25 yrs and over) with low profiles (LP) on the Strong-Campbell Interest Inventory (SCII) or SVIB female Occupational Scales differ from women who have high profiles (HP) with respect to measured personality characteristics (California Psychological Inventory [CPI]) and vocational needs (Minnesota Importance Questionnaire [MIQ]). 467 Ss for both SCII and SVIB groups, LP Ss differed from HP Ss on 35 CPI items and scored significantly lower on 9 CPI scales (e.g., Dominance, Capacity for Status, Sociability) and on 3 MIQ needs (Authority, Creativity, and Responsibility). LP and HP Ss differed significantly on 96 of the 110 SCII scales that are relevant to women and on 52 of the 85 female SVIB scales. At a response difference of at least 28%, 70 SCII and 61 SVIB items best separated LP and HP Ss. Compared with LP Ss, HP Ss liked activities that involved writing, public speaking, and leadership. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
147.
148.
Isoprenoids: Remarkable diversity of form and function 总被引:3,自引:0,他引:3
The isoprenoid biosynthetic pathway is the source of a wide array of products. The pathway has been highly conserved throughout
evolution, and isoprenoids are some of the most ancient biomolecules ever identified, playing key roles in many life forms.
In this review we focus on C-10 mono-, C-15 sesqui-, and C-20 diterpenes. Evidence for interconversion between the pathway
intermediates farnesyl pyrophosphate and geranylgeranly pyrophosphate and their respective metabolites is examined. The diverse
functions of these molecules are discussed in detail, including their ability to regulate expression of the β-HMG-CoA reductase
and Ras-related proteins. Additional topics include the mechanisms underlying the apoptotic effects of select isoprenoids,
antiulcer activities, and the disposition and degradation of isoprenoids in the environment. Finally, the significance of
pharmacological manipulation of the isoprenoid pathway and clinical correlations are discussed. 相似文献
149.
The risks associated with batch processing in the manufacture of chemicals and pharmaceuticals via highly exothermic reactions are of special interest due to the possibility of runaway reactions. o-Nitrated benzoyl chlorides are intermediates in the production of agrochemicals and are produced via the reaction of o-nitrated carboxylic acids with thionyl chloride in a solvent mixture. ortho-Nitrated acyl chlorides have exploded violently on attempted distillation on numerous occasions. An inadequate investigation of the process prior to large-scale operation is the most likely cause. Here we present preliminary results of studies on the decomposition of 2-nitrobenzoyl chloride. This study has revealed that the decomposition reaction is strongly condition dependent. The heating rate of the sample plays a preponderant role in the course of the decomposition reaction. That renders the interpretation of differential scanning calorimetry (DSC) or adiabatic calorimetry measurements, which are routinely used to assess the thermochemistry and safety of the large-scale reactions, problematic. Following this on-going study, we report here key features of the system that have been identified. 相似文献
150.
Chuang HF Cooper SM Meyyappan M Cruden BA 《Journal of nanoscience and nanotechnology》2004,4(8):964-967
Interfacial thermal resistance results of various nanotube and nanofiber coatings, prepared by chemical vapor deposition (CVD) methods, are reported at relatively low clamping pressures. The five types of samples examined include multi-walled and single-walled nanotubes growth by CVD, multi-walled nanotubes grown by plasma enhanced CVD (PECVD) and carbon nanofibers of differing aspect ratio grown by PECVD. Of the samples examined, only high aspect ratio nanofibers and thermally grown multi-walled nanotubes show an improvement in thermal contact resistance. The improvement is approximately a 60% lower thermal resistance than a bare Si-Cu interface and is comparable to that attained by commercially available thermal interface materials. 相似文献