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71.
72.
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
73.
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
74.
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
75.
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
76.
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
77.
Chingszu Lin Zhifeng Huang Masako Kanai-Pak Jukai Maeda Yasuko Kitajima Mitsuhiro Nakamura 《Advanced Robotics》2019,33(6):278-292
With the number of hospital stays increasing, nurses require more training to handle a variety of patients. However, time for training in nursing schools is limited, and students lack the opportunity to practice on a diverse variety of patients. Using a robot to simulate actual patients, this study observes the learning transfer effect of practice on practice-similar and practice-dissimilar skills from one patient to another, and investigates which types of practice suit which kinds of training. An experiment was conducted by administering a pre-test, practice, a post-test, and a transfer test to two groups (N?=?8), each with different practice-related skills. The evaluation used a checklist covering required skills that were either similar or dissimilar across groups, depending on their practice. The effect of practice can be observed through a comparison of skills similar to one group but dissimilar to the other. The results show that practice facilitates learning transfer on similar skills but not, or to a lesser degree, on dissimilar skills. Furthermore, if skills needed to handle given symptoms are unfamiliar or inaccessible to students, practice related to those symptoms should be emphasized through simulated training with robots. 相似文献
78.
The enormous magnitude and variety of microwave applications in household, commercial and industrial food processing creates a strong motivation for improving the energy efficiency and hence, sustainability of the process. This review critically assesses key energy issues associated with microwave food processing, focusing on previous energy performance studies, energy performance metrics, standards and regulations. Factors affecting energy-efficiency are categorised into source, load and source-load matching factors. This highlights the need for highly-flexible and controllable power sources capable of receiving real-time feedback on load properties, and effecting rapid control actions to minimise reflections, heating non-uniformities and other imperfections that lead to energy losses. A case is made for the use of solid-state amplifiers as alternatives to conventional power sources, magnetrons. By a full-scale techno-economic analysis, including energy aspects, it is shown that the use of solid-state amplifiers as replacements to magnetrons is promising, not only from an energy and overall technical perspective, but also in terms of economics. 相似文献
79.
《工程(英文)》2019,5(4):624-636
An intelligent manufacturing system is a composite intelligent system comprising humans, cyber systems, and physical systems with the aim of achieving specific manufacturing goals at an optimized level. This kind of intelligent system is called a human–cyber–physical system (HCPS). In terms of technology, HCPSs can both reveal technological principles and form the technological architecture for intelligent manufacturing. It can be concluded that the essence of intelligent manufacturing is to design, construct, and apply HCPSs in various cases and at different levels. With advances in information technology, intelligent manufacturing has passed through the stages of digital manufacturing and digital-networked manufacturing, and is evolving toward new-generation intelligent manufacturing (NGIM). NGIM is characterized by the in-depth integration of new-generation artificial intelligence (AI) technology (i.e., enabling technology) with advanced manufacturing technology (i.e., root technology); it is the core driving force of the new industrial revolution. In this study, the evolutionary footprint of intelligent manufacturing is reviewed from the perspective of HCPSs, and the implications, characteristics, technical frame, and key technologies of HCPSs for NGIM are then discussed in depth. Finally, an outlook of the major challenges of HCPSs for NGIM is proposed. 相似文献
80.
现有的属性约简方法大部分关注决策系统中的所有决策类,而在实际决策过程中决策者往往仅关注决策系统中的一种或几种决策类。针对上述问题,提出基于多特定决策类的不完备决策系统正域约简的理论框架。首先,给出不完备决策系统单特定决策类正域约简的概念;第二,将单特定决策类正域约简推广到多特定决策类,构造了相应的差别矩阵及区分函数;第三,分析并证明了相关定理,提出基于差别矩阵的不完备决策系统多特定决策类正域约简算法(PRMDM);最后,选取4组UCI数据集进行实验。在数据集Teaching-assistant-evaluation、House、Connectionist-bench和Cardiotocography上,基于差别矩阵的不完备决策系正域约简算法(PRDM)的平均约简长度分别为4.00、13.00、9.00和20.00,PRMDM算法(多特定决策类中决策类数目为2)的平均约简长度分别为3.00、8.00、8.00和18.00。实验结果验证了PRMDM算法的有效性。 相似文献