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101.
按照JJG 814-2015规定,自动电位滴定仪需进行电计示值误差和仪器示值误差检定,本文例举对这两项检定结果进行不确定度评定,供相关人员参考。 相似文献
102.
本文主要研究随机环境中配对依赖人口数两性 Galton-Watson 分枝过程的条件均值增长率的极限性质.利用上可加函数的性质,得到配对单元平均增长率的极限性质和该过程条件均值的上界和下界.文中给出了关于过程条件均值增长率的两个序列,利用配对单元平均增长率的性质,获得了这两个序列的极限性质.随机环境中配对依赖人口数两性分枝过程比较复杂,本文的结论推广了现有的研究成果. 相似文献
103.
Dingzong ZHANG Youjun HU Nong XIANG Cheng YANG Wei SHEN Yanqing HUANG Hongbo LIU 《等离子体科学和技术》2021,23(11):115101-8
The classical prompt loss of fast ions produced by minority ion cyclotron resonance heating(ICRH)is studied by a guiding center orbit following code in the Experimental Advanced Superconducting Tokamak(EAST).It is found that the loss of fast ions produced by ICRH mainly appears in both ends of the resonance layer,while the loss of fast ions in the middle resonance layer is very small.The dominant fast loss comes from trapped ions,rather than from passing ions.Controlling the location of resonance layer at the plasma core may be more beneficial to the EAST tokamak ICRH.In addition,the loss distribution of fast ions is studied.The results show that the fast ions are mainly lost near the midplane in the poloidal direction,but almost uniformly in the toroidal direction.Moreover,we investigate the dependence of fast ion loss on the ICRH power.The simulation results show that the loss fraction of fast ions in both ends of the resonance region increases with the ion cyclotron range of frequencies(ICRF)power,but barely affects the loss of fast ions in the middle region. 相似文献
104.
Riemann-Liouville分数阶微积分算子是一类带有一个函数的分数阶微积分算子的特殊情形,以Riemann-Liouville分数阶微积分算子的积分中值定理和微分中值定理为基础,我们得到了一类带有一个函数的分数阶微积分算子的积分中值定理和微分中值定理,并给出其在计算方面的一些应用。 相似文献
105.
针对当前通信系统入侵行为自动识别技术存在入侵信号样本识别成功率较低、误识别率和漏识别率较高的问题,提出基于 GA-SVM 算法的通信网络入侵信号自动识别技术。利用混沌原理提取通信网络入侵的非平稳信号时域特征,并凭借自回归模型提取对应频域特征,捕捉邻域入侵信号间的非线性时空动作频率,评价相邻行为间的状态关联性,预测入侵信号后续行为,完成入侵信号的识别。实验表明,所提方法识别精度高、误识别率较低,漏识别率非常低,具有可应用于实际的理论价值。 相似文献
106.
This study compared three representative observational methods for assessing musculoskeletal loadings: Ovako Working Posture Analysis System (OWAS), Rapid Upper Limb Assessment (RULA), and Rapid Entire Body Assessment (REBA). The comparison was based on 209 cases of upper-body musculoskeletal disorders (MSDs) diagnosed by medical doctors. The most awkward/stressful posture in each participant's tasks was assessed using these techniques. Postural loadings were rated more highly by the RULA than by the OWAS and REBA (p < 0.01). The chi-square test and logistic regression analysis showed that only RULA grand score and action level, and REBA action level were associated with MSD work-relatedness (p < 0.01, p < 0.05, and p < 0.05, respectively). The percentage concordant values of the logistic model for the RULA grand score and action level were 52.4% and 44.8%, respectively, while the percentage concordant value for the REBA action level was 22.1%. Therefore, the RULA may be the best system for estimating the postural loads and work-relatedness of MSDs.Relevance to industryWork-related musculoskeletal disorders are the leading cause of workplace disability in the developed countries. For preventing the disorders, quantification of musculoskeletal loads is required. 相似文献
107.
仲春华 《皮革制作与环保科技》2021,(5):34-35
社会经济的快速发展对生态环境造成了较大破坏,并产生了一系列连锁反应,不利于我国可持续发展目标的实现。为此,必须要切实做好环境监测工作。本文从环境监测的概念出发,就现阶段的环境监测现状进行了分析,并在此基础上阐述了环境监测工作未来发展及优化对策,以供参考。 相似文献
108.
论述了炼铁-炼钢界面的紧凑衔接技术,涉及多维物质流的衔接、传递、匹配及缓冲等过程。从各角度综合分析得出,该界面衔接布置紧凑,占地面积小,实施MES系统的“在线铁水罐跟踪系统”使炼铁-炼钢界面减少了铁水罐周转个数,相对传统方式的铁水包输运方式,保温剂使用量平均减少了0.483 kg/t(铁),铁水入炉温度提高约60 ℃。同时,确保了100%的“一罐到底”命中率,大幅节省了耐材费用,具有显著的经济效益和社会效益。 相似文献
109.
The objective of this study was to identify what competencies are identified in the literature as necessary for Industry 4.0 by conducting a survey of the literature and a scientific mapping of the evolution of the issues related to the qualification of professionals for Industry 4.0 and possible paths for research and education. A search was conducted on the Scopus, Web of Science and Science Direct databases for the interval from 2010 to 2018. This systematic review revealed topics and authors currently specialized in the field and allowed mapping the field of study. The identification of journals and keywords useful in future studies was also an object of this study. SciMAT software was used for the systematic literature review. The results are highlighted by the set of competencies (knowledge and skills) that must be developed in professional education to accompany the new industrial revolution, as well as the importance of integrating efforts by companies, governments and universities. These efforts should focus on creating “learning factories”, which are understood to be environments that provide practical experiences to these professionals, preparing them in the best way possible for the requirements of Industry 4.0. This conceptual map showed that the main competencies needed include skills: (leadership, strategic vision of knowledge, self-organization, giving and receiving feedback, pro-activity, creativity, problem solving, interdisciplinarity, teamwork, collaborative work, initiative, communication, innovation, adaptability, flexibility and self-management) and knowledge of contemporary fields (information and communication technology, algorithms, automation, software development and security, data analysis, general systems theory and sustainable development theory). 相似文献
110.
This paper presents a narrative literature review that addresses the issue of how disabled and aging people access the arts through technology. Our review synthesized 56 studies about disabled and aging people's experiences of access through technology, with a focus on methods used and accounts of user experiences/stories to inform a Canadian research and development initiative called Accessing the Arts. We urge designers and developers to consider the complex, multimodal sociotechnical relationships surrounding technology and access—or TechnoAccess—as they develop technology with disability, aging and access in mind. Although existing evidence offers ways to improve everyone's access to the arts, recommendations are provided for research around access and technology as an inherently politicized topic that must be informed by disabled and aging people's intersectional cultural experiences, including how they wish to use technology to access the arts. 相似文献