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81.
This study was concerned with "peaking", which is the tendency for electrical-energy users to consume at high rates for brief periods during the day. Peaking results in the inefficient use of generating facilities, which may lead to unfavorable effects on the environment, such as the construction of new energy producing facilities or the activation of older, less safe, generating units. A continuous data collection system to monitor consumption of electrical energy was installed in the homes of three volunteer families. Information, feedback, and incentives were evaluated for their effects on peak energy consumption. A combination of feedback plus incentives was most effective and reduced peaking about 50%. Removal of experimental treatments resulted in a return to pre-treatment patterns of consumption.  相似文献   
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Studies using a triaxial accelerometer and heart rate (HR) simultaneously for estimating energy expenditure (EE) during uphill exercise are rare. Exploring the optimal location for placing the accelerometer for predicting EE during uphill exercise is essential. Sixteen healthy male participants (M ± SEM; age 25.00 ± 0.61 years; body weight 74.13 ± 2.51 kg; body height 1.74 ± 0.01 m; body mass index 24.30 ± 0.63 kg/m2) exercised on a treadmill under 12 conditions (4 speeds and 3 gradients) on 3 days. Triaxial accelerometers, an HR recorder, and a metabolic measurement system were simultaneously used. Accelerometer outputs from various anatomical locations (upper arm, chest, lower back, waist, thigh, and instep) showed significant positive correlations with EE (0.819, 0.846, 0.816, 0.820, 0.672, and 0.669, respectively; p < .05). The linear regression equation for changes in HR showed the highest coefficient of determination (r2) of .837 with 87.9% reliability. When the HR signal was included, the r2 value (> .842) and reliability (87.9%) between the accelerometer outputs and EE improved. Accelerometer outputs from the waist position alone provide highly accurate EE values. Using both accelerometer outputs and HR for EE estimation during uphill exercise is feasible and improves the accuracy of EE prediction.  相似文献   
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王峥芳  周雅  刘翔平 《心理科学》2011,34(6):1372-1378
目的:研究旨在考察数学学习中的流畅体验,探讨流畅体验、内/外动机、数学焦虑及数学成绩的关系。方法:招募296名高中生,在数学月考后完成自编考试流畅体验量表、学习动机量表、数学焦虑量表。结果:路径分析表明,存在四条显著路径,即内部动机→流畅状态→数学成绩;数学焦虑→流畅状态→数学成绩;外部动机→流畅状态→数学成绩;外部动机→数学成绩。结论:只有通过考试过程中的流畅体验,内部动机和数学焦虑才能影响考试成绩。  相似文献   
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The examination of blood flow velocity (BFV) changes during the performance of mental tasks is one of the applications of transcranial Doppler (TCD) ultrasonography. The purpose of this review is to summarize the results of the functional TCD literature, to investigate the effects of methodological differences between studies, and to provide guidelines for future research. It is concluded that larger series of more homogeneous groups concerning age and handedness, and stricter criteria for subject selection and laboratory setting are required. The implication of quantitative and qualitative performance measures and psychological parameters (motivation, anxiety, and task anticipation) could also yield important information. We recommend future agreement upon a more standardized methodology. TCD promises to be a useful tool to provide further insight into the cerebral organization and temporal reactivity of the human brain.  相似文献   
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This paper is a search for the origins and nature of human consciousness. This portion, the first part of two, takes up a signal work of Jung and one of Freud, both published in 1911 and both deriving thinking as the first embodiment of higher mental functions. Thinking and consciousness (and subsequently spirit) are elaborated in terms of the nature and vicissitudes of libido. Jung's less well understood theory regarding a quantitative libido is particularly addressed as are his non-Cartesian ways of reasoning. Also addressed is Jung's turning away in the final analysis from a frankly metaphysical and transcendent position as compared to the pre-Socratic philosophers with whom focused thinking began in the western world. Differentiation is made between mechanistic and energetic field dynamics in how reality is viewed.  相似文献   
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Summary  Big History – an integral conception of the past since the Big Bang until today – is a novel subject of cross-disciplinary interest. The concept was construed in the 1980–1990s simultaneously in different countries, after relevant premises had matured in the sciences and humanities.Various versions and traditions of Big History are considered in the article. Particularly, most of the Western authors emphasize the idea of equilibrium, and thus reduce cosmic, biological, and social evolution to the mass-energy processes; the informational parameter involving all mental and spiritual aspects are seen as epiphenomena of material structures” complication that do not play their own role in evolution. In Russian tradition ascending to A. Bogdanov, E. Bauer, I. Prigogine, and E. Jantsch, sustainable non-equilibrium patterns are used. This implies attention to the pan-material sources and evolution of mental capacities and spiritual culture (as basic anti-entropy instruments) and humans” growing intervention in the material processes on Earth and outside it.The non-equilibrium approach in the context of modern control and self-organization theories, alters the portrayal of the past, and still more dramatically, estimation of the civilization’s potential perspectives.  相似文献   
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Since blushing is difficult to detect in people with dark skin, their experience of blushing may differ fundamentally from people with fair skin. To investigate this issue, cheek temperature and forehead blood flow were measured in 16 Caucasians and 16 Indians during mental arithmetic and singing. Caucasians (particularly females) thought that they blushed more intensely than Indians, and also reported greater self-consciousness when singing. Vascular responses did not differ between groups. However, skin tone moderated the association between vascular responses and ratings of self-consciousness, blushing intensity, blushing propensity and fear of negative evaluation. These findings support the notion that the visibility of blushing influences the nature of emotions experienced in embarrassing social encounters.  相似文献   
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The perilous disease in the worldwide now a days is brain tumor. Tumor affects the brain by damaging healthy tissues or intensifying intra cranial pressure. Hence, rapid growth in tumor cells may lead to death. Therefore, early brain tumor diagnosis is a more momentous task that can save patient from adverse effects. In the proposed work, the Grab cut method is applied for accurate segmentation of actual lesion symptoms while Transfer learning model visual geometry group (VGG-19) is fine-tuned to acquire the features which are then concatenated with hand crafted (shape and texture) features through serial based method. These features are optimized through entropy for accurate and fast classification and fused vector is supplied to classifiers. The presented model is tested on top medical image computing and computer-assisted intervention (MICCAI) challenge databases including multimodal brain tumor segmentation (BRATS) 2015, 2016, and 2017 respectively. The testing results with dice similarity coefficient (DSC) achieve 0.99 on BRATS 2015, 1.00 on BRATS 2015 and 0.99 on BRATS 2017 respectively.  相似文献   
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