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Conducted 2 laboratory experiments with 117 undergraduates to examine (1) the effect of assigned goal difficulty on arousal (self-report and heart rate), cognition (perceived norm, self-efficacy strength, and personal goal), and behavioral (task performance) measures and (2) the role of heart rate as a mediator of the goal-difficulty–performance relation. All Ss performed a task requiring cognitive and physical responses. Results of both experiments demonstrate that assigned goal difficulty affected heart rate, cognition, and task performance and that heart rate change was positively related to the cognitive and behavioral measures. Regression analyses suggested that a cognitive–affective mechanism may mediate the goal-difficulty–performance relation. Discussion is focused on the theoretical and practical implications of integrating an arousal concept within goal-setting theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
Lowe Rob; Bennett Paul; Walker Ian; Milne Sarah; Bozionelos George 《Canadian Metallurgical Quarterly》2003,22(5):464
The theory of planned behavior suggests attitudes are a product of salient beliefs. This study examined whether aggregating salient beliefs was plausible within a more biologically centered information-processing environment. A neural network was used to examine associations among beliefs relating to exercise intention. Data on intentions and behavioral, normative, and control beliefs from 114 respondents were used to train (by error backpropagation) a neural network to associate beliefs with intention. The R2 between the network's estimated and self-reported intention was .66. The network's representation comprised 6 belief profiles associated with high, moderate, or low behavioral intention. The neural network accommodated complex relationships among beliefs and belief-intention associations and indicated how high-level constructs such as attitudes may be viewed as the best fit (compromise state) between aroused beliefs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Ultrathin dielectric materials that provide high capacitance values are needed for 64- and 256-Mb stacked DRAMs. It is shown that capacitance values as high as 12.3 fF/μm2 can be obtained with ultrathin nitride-based layers deposited on rugged polysilicon storage electrodes. These films present the reliability and low leakage current levels required for 3.3-V applications. The nitride thickness, however, cannot be scaled much below 6 nm to avoid the oxidation-punchthrough mechanisms that appear when too-thin films are unable to withstand the reoxidation step 相似文献
25.
Ian McKeown 《Coloration Technology》1994,110(4):136-137
Over the last few years, Polaroid has been actively trying to reduce the amount of waste produced at its sites. In this article, Ian McKeown looks at the measures taken at the UK site in Scotland to achieve this aim. 相似文献
26.
Research has continued in the field sidechain liquid crystal polymers over recent years, but it is becoming clearer that this research is being directed away from the traditional technology areas of electro-optic devices and researchers are developing new and exciting applications for this novel state of matter. 相似文献
27.
Salvatore A. Bruno Donald K. Swanson Ian Burn 《Journal of the American Ceramic Society》1993,76(5):1233-1241
Advantages of chemically prepared powders for electronic ceramics have been demonstrated for a number of multilayer capacitor (MLC) dielectrics. A cost-efficient precipitation process was developed to produce undoped or doped crystalline barium titanate powder with a narrow particle size distribution close to 0.5 μm. More complex compositions, e.g., barium-neodymium titanate, were amorphous as precipitated but could be crystallized by calcination below 1000°C. Additional compositional modifications, to adjust electrical properties or to lower sintering temperature, were accomplished by doping the surface of the powder particles using a solution coating process. Exceptional fired densities and electrical performance were obtained. 相似文献
28.
Arachidonic acid (AA) in the diet can be efficiently absorbed and incorporated into tissue membranes, resulting in an increased production of thromboxane A2 by platelets and increased ex vivo platelet aggregability. Results from previous studies have shown that AA is concentrated in the membrane phospholipids of lean meats. However, the concentration of AA in the visible fat portion of meats also may be significant despite being ignored in most studies. The aim of this study was to accurately quantitate the AA content of visible fat and the lean portion of beef, lamb, pork, chicken, duck, and turkey. The visible fat of meat contained a significant quantity of AA, ranging from 20 to 180 mg/100 g fat, whereas the AA content of the lean portion of meat was lower, ranging from 30 to 99 mg/100 g lean meat. Beef and lamb meats contained lower levels of AA in both the visible fat and lean portion than that from the other species. The highest level of AA in lean meat was in duck (99 mg/100 g), whereas pork fat had the highest concentration for the visible fats (180 mg/100 g). The lean portions of beef and lamb contained the higher levels of n-3 polyunsaturated fatty acids (PUFA) compared with white meats which were high in AA and low in n-3 PUFA. The present data indicate that the visible meat fat can make a contribution to dietary intake of AA, particularly for consumers with high intakes of fat from pork or poultry meat. 相似文献
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Chen Jiaoyan Hu Pan Jimenez-Ruiz Ernesto Holter Ole Magnus Antonyrajah Denvar Horrocks Ian 《Machine Learning》2021,110(7):1813-1845
Machine Learning - Semantic embedding of knowledge graphs has been widely studied and used for prediction and statistical analysis tasks across various domains such as Natural Language Processing... 相似文献