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1.
《International Journal of Hydrogen Energy》2022,47(9):5757-5765
At present, as the demand for electricity increases in all sectors, there is an urgent need to introduce alternative renewable energy sources into modern energy systems. Renewable energy sources, which consist of solar (photovoltaic, PV), wind and hydro power, are key alternative sources of “green energy’’ energies, but it can also be used to produce “green” hydrogen. Thanks to scientific and technological progress, the cost of photovoltaic solar radiation converters is constantly decreasing at a high rate, which makes it possible to build solar power plants of sufficiently large capacity. In the coming decades, solar energy will become an incentive for the economic development of countries that have the maximum “solar” resource. The Republic of Tajikistan is one of these countries with a high potential for solar energy.The article presents an analysis of the resources and potential of solar energy in the Republic of Tajikistan. The study of electromagnetic transients in networks with photovoltaic solar power plants is performed. The main equations, simulation model and calculations of transients are presented, taking into account changes in voltage on DC buses. An algorithm for controlling the system of automatic control of output parameters is proposed. The analysis of dynamic and static modes in parallel operation of a solar power plant with the grid is carried out. A block diagram and computer model is constructed in the MATLAB package together with Simulink and Power System Blockset. 相似文献
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Bin Zhang Xuesong Jiang Fei Shen Xueming He Yong Fang Qiuhui Hu 《International Journal of Food Science & Technology》2021,56(6):2588-2595
This work intends to develop an online experimental system for screening of deoxynivalenol (DON) contamination in whole wheat meals by visible/near-infrared (Vis/NIR) spectroscopy and computer vision coupling technology. Spectral and image information of samples with various DON levels was collected at speed of 0.15 m s−1 on a conveyor belt. The two-type data were then integrated and subjected to chemometric analysis. Discriminant analysis showed that samples could be classified by setting 1000 μg kg−1 as the cut-off value. The best correct classified rate obtained in prediction was 93.55% based on fusion of spectral and image features, with reduced prediction uncertainty as compared to single feature. However, quantification of DON by quantitative analysis was not successful due to poor model performance. These results indicate that, although not accurate enough to provide conclusive result, this coupling technology could be adopted for rapid screening of DON contamination in cereals and feeds during processing. 相似文献
4.
Risk perceptions and technology innovativeness are the two primary factors related to the adoption of mobile technologies. The current study examines the role of technology innovativeness and risk perceptions on smartphone use and dependence in an Asian context. A total of 9086 participants were recruited through online surveys from ten Asian countries. Ordinary least squares regression analyses revealed the effects of technology innovativeness, information security, privacy concern, and their interactions on smartphone use and dependence. Moreover, based on users’ smartphone usage patterns and perceptions, this paper identified four homogeneous groups using cluster analysis. Results shows that Asian smartphone users can be segmented into four groups: innovators, conservatives, moderators, and laggards. The four clusters show significant differences in demographic features. Theoretical and practical implications are discussed based on these findings. 相似文献
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This exploratory quantitative study compared schoolchildren’s scores on 15 computer games to their scores on the neuropsychological test, NEPSY-II, to determine whether these games utilize predicted cognitive skills. Forty-three children aged 7–12 from different ethnic groups participated in this study. There was an almost equal split between girls and boys, some of whom reported mild learning difficulties. Many a priori predicted correlations were confirmed, with a medium to high effect. Eleven games shared their highest correlation with one or more of the predicted cognitive skills as measured by the NEPSY-II, which provided evidence that these computer games use specific cognitive functions. This suggests that similar computer games could be used to assess, practice, or monitor cognitive skills among schoolchildren. 相似文献
7.
We present an interactive material acquisition system for average users to capture the spatially varying appearance of daily objects. While an object is being scanned, our system estimates its appearance on‐the‐fly and provides quick visual feedback. We build the system entirely on low‐end, off‐the‐shelf components: a Kinect sensor, a mirror ball and printed markers. We exploit the Kinect infra‐red emitter/receiver, originally designed for depth computation, as an active hand‐held reflectometer, to segment the object into clusters of similar specular materials and estimate the roughness parameters of BRDFs simultaneously. Next, the diffuse albedo and specular intensity of the spatially varying materials are rapidly computed in an inverse rendering framework, using data from the Kinect RGB camera. We demonstrate captured results of a range of materials, and physically validate our system. 相似文献
8.
Alexander J.A.M. van Deursen Jan A.G.M. van Dijk Peter M. ten Klooster 《Telematics and Informatics》2015
We investigate types of Internet activities among a representative sample of the Dutch population from 2010 to 2013. We examined usage patterns of seven types of Internet activities (i.e., information, news, personal development, commercial transaction, social interaction, leisure, and gaming) and related these patterns with gender, age, education, and income. Activities related to news, personal development, commercial transaction, and social interaction increased in popularity. For most capital enhancing activities, men, younger people, higher educated people, and people with higher than average incomes were prominent. These observations, however, are subject to change. The Internet seems to provide increasingly more capital-enhancing opportunities for those with higher education and income, which would accordingly reinforce their already strong positions in society. 相似文献
9.
This study designs and evaluates a new nail clipper for the elderly using ergonomic methods. The nail clipper usage problems and requirements were collected first. After requirement analysis we applied ergonomic simulation in redesigning the nail clipper and developing a pedal plate. A usability test was conducted to evaluate both typical and newly developed nail clippers using 20 elder participants. The dependent measures were the total number of nails clipped, completion time and discomfort and satisfaction subjective ratings. The experimental results indicated that the newly developed nail clipper was superior to the typical one in subjective ratings for discomfort and satisfaction. The performance of the newly-developed nail clipper is similar to that of the typical clipper. Some important nail clipper design implications for the ageing population are discussed.Relevance to industryWith the increase in the elderly population, problems caused by aging have gradually emerged. Aging may cause the elderly inconvenience in using many household objects that are not specifically designed for the elderly. Therefore, industrial designers should try to redesign household objects to enhance living quality for the elderly. This study used nail clipper design as an example to show how to apply ergonomic methods in product design. 相似文献
10.
As the standard of living constantly improves, and as life expectancy increases in developed countries, the number of adults who want to have a gratifying life increases as well. Furthermore, although the Internet offers a world of potentially rewarding experiences, there is much heterogeneity among older people with respect to those who are able to benefit from its use. To reduce this gap, public access and digital literacy programs have been implemented. The aim of the study was to find out the extent to which these programs moderate the effects of age and socioeconomic status on social access to and use of the Internet in a sample of older users in Spain. Through quota sampling of retired users over 54 years of age in Spain (N = 560), who were regular users of public supports for Internet access, a structural equation modeling and multi-group analysis was conducted. The data showed a staggered association of access indicators (physical access, digital skills and social e-activities) on the social gratifications obtained, as well as the moderating role of institutional supports. This study provides empirical evidence of the ability of public supports to moderate the effect of socioeconomics inequalities on access and social exploitation of the Internet by older people. The findings point to the need to strengthen digital literacy actions, especially in supports that are more sensitive to the effect of age and socio-economic status. 相似文献