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61.
在新时期下,传统的英语教学方法已经不适合学生的学习和发展了,经过笔者的研究和分析发现,小学生对故事似乎是非常感兴趣,所以就针对多媒体技术在小学英语故事教学中的应用进行了几点尝试。 相似文献
62.
本文借助计算机中的视觉自动检测技术来测量在果实表面的着色度,并对该颜色进行了分级,进一步的对颜色进行分析与研究,进而来获得出最终的水果果实的彩色图像,进一步的分析出对应的结果。因此,在本文中,对果实表面颜色进行了全面综合的分析与研究,进而来得出对应的果实颜色分级标准和原则。 相似文献
63.
The solder paste printing (SPP) is a critical procedure in a surface mount technology (SMT) based assembly line, which is one of the major attributes to the defect of the printed circuit boards (PCBs). The quality of SPP is influenced by multiple factors, such as the squeegee speed, pressure, the stencil separation speed, cleaning frequency, and cleaning profile. During printing, the printer environment is dynamically varying due to the physical change of solder paste, which can result in a dynamic variation of the relationships between the printing results and the influential factors. To reduce the printing defects, it is critical to understand such dynamic relationships. This research focuses on determining the printing performance during printing by implementing a wavelet filtering-based temporal recurrent neural network. To reduce the noise factor in the solder paste inspection (SPI) data, this research applies a three-dimensional dual-tree complex wavelet transformation for low-pass noise filtering and signal reconstruction. A recurrent neural network is utilized to model the performance prediction with low noise interference. Both printing sequence and process setting information are considered in the proposed recurrent network model. The proposed approach is validated using practical dataset and compared with other commonly used data mining approaches. The results show that the proposed wavelet-based multi-dimensional temporal recurrent neural network can effectively predict the printing process performance and can be a high potential approach in reducing the defects and controlling cleaning frequency. The proposed model is expected to advance the current research in the application of smart manufacturing in surface mount technology. 相似文献
64.
There is growing recognition that blockchain technology has significant potential to alter how organizations and people work and communicate. However, theoretical guidance concerning how organizations leverage blockchain technology to enhance value creation for users is still limited. Grounded in the socio-technical perspective and leveraging the rich data obtained from case analyses of blockchain-enabled online communities, this paper develops a theoretical model to identify the core value drivers that blockchain enables for online communities. The core value drivers include: a reputation-value system, data ownership mechanisms, and verification & tracking mechanisms. Our findings suggest that these three value drivers enhance value creation of online communities by motivating participation and protecting contributions. 相似文献
65.
66.
乡村产业中的化石能源设备逐渐被电能技术替代,引起了乡村负荷波动增大、部分时段产生集中高负荷的问题。为了解决以上问题,将低品位清洁能源应用至乡村的茶叶生产中,针对烘茶全过程的工艺要求提出了跨临界CO2热泵烘茶技术;并以某茶叶生产乡村为对象,对其代表台区的全年日用电量及产茶日负荷进行了分析,得出采用CO2热泵烘茶后其负荷得到大幅度削减,整体可降低至原负荷的39.6%~46.8%,峰值负荷与平时负荷的比值由原本的13.6降至5.4~6.2。跨临界CO2热泵应用至农产品生产中可有效缓解乡村供电压力。 相似文献
67.
卢勇锋 《皮革制作与环保科技》2021,(5):50-51
环境检测技术对于环境的决策及监管有着很大的影响,但目前在我国的环境检测技术仍然还存在一定的问题,仍然有待完善。因此,本文针对环境检测技术现存问题进行了研究分析,并且提出了一些相应的有效对策。 相似文献
68.
Commercialization of technologies has attracted increasing attention over the past years due to its role in improving national competitiveness. Iran has not been an exception as the country's policy-makers have been actively engaged in crafting national policies to facilitate and promote commercialization of technologies. The popularity of the existing policies in this field, however, has not been properly researched. Our research, by following a survey study methodology, aims for the first time to address this gap. The study looks at popularity of governmental policies aimed at supporting commercialization of patented technologies in Iran, based on the careful study of 10 cases of successfully commercialized patented technologies in Iran. Our results indicate that the commercialization process of the studied patented technologies was very much affected by some company/technology-specific characteristics. The study shows that the two policy measures with the highest perceived popularity were the financial supports and the services offered by incubation centers. Our results also show that some of the existing supportive policy measures did not serve the intended purposes and some other measures need to be fine-tuned, as far as the studied cases are concerned, such as frequently held invention and innovation exhibitions and the government-supported media coverage. 相似文献
69.
Xipei Ren Bin Yu Yuan Lu Yu Chen Pearl Pu 《International journal of human-computer interaction》2019,35(10):870-885
This research was motivated by a desire to help office workers change their sedentary behavior because a prolonged sedentary posture increases the risks of developing musculoskeletal injuries and chronic diseases, thus threatening their physical and psychological well-being. Regular breaks involving low-effort physical activities are effective in reducing the adverse impacts of inactive behaviors. In this article, we present the design of a posture-based interactive system called HealthSit, which was developed to promote a short lower-back stretching exercise during work breaks. Through a within-subject study involving 30 office workers, the effectiveness of HealthSit in facilitating the stretching exercise was examined by making comparisons between an interaction-aided, a guided, and a self-directed exercise mode. We also used HealthSit as a research probe to investigate the interactivity of the system in enhancing user experience and the psychological benefits of the fitness breaks. Compared with the other two modes, the interaction-aided exercise mode significantly improved the quality of the stretching exercise and enhanced motivation and emotional state. These results confirm the effectiveness of HealthSit in supporting fitness breaks as a new workplace technology. Based on our study, a set of design implications have been derived for technology-assisted fitness work breaks. 相似文献
70.
以Orbit专利分析平台为主要研究工具,从专利文献中抽取专利数量指标和专利质量指标来构建评价薄板坯连铸连轧技术竞争力和企业创新能力的指标体系,结合其他文献研究的成果,从产业发展的实际出发做出分析,系统揭示了自薄板坯连铸连轧技术开发以来的技术进步、专利布局、发展演化、国内外发展现状、技术竞争实力等,有助于在专利文献提供的线索启发下开发新产品、新技术,从而有效提高研发效率。 相似文献