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1.
Digital Module 05: Diagnostic Measurement—The G‐DINA Framework https://ncme.elevate.commpartners.com
In this ITEMS module, we introduce the generalized deterministic inputs, noisy “and” gate (G‐DINA) model, which is a general framework for specifying, estimating, and evaluating a wide variety of cognitive diagnosis models. The module contains a nontechnical introduction to diagnostic measurement, an introductory overview of the G‐DINA model, as well as common special cases, and a review of model‐data fit evaluation practices within this framework. We use the flexible GDINA R package, which is available for free within the R environment and provides a user‐friendly graphical interface in addition to the code‐driven layer. The digital module also contains videos of worked examples, solutions to data activity questions, curated resources, a glossary, and quizzes with diagnostic feedback. 相似文献
2.
The field of educational measurement has evolved considerably since the first doctoral programs were established. In response, programs have typically tacked on courses that address newly developed theories, methods, tools, and techniques. As our review of current programs evidences, this approach produces artificial distinctions among topics and techniques that are in fact a tightly coupled whole. This position paper advocates a redesign of the scope and sequence for doctoral programs focused on the preparation of the next generations of educational measurement specialists; a redesign that reflects the full life‐cycle of instrument development and use. 相似文献
3.
Haicheng Li Yinji Ma Ziwei Liang Zhouheng Wang Yu Cao Yuan Xu Hua Zhou Bingwei Lu Ying Chen Zhiyuan Han Shisheng Cai Xue Feng 《国家科学评论(英文版)》2020,7(5):849
According to the statistics of the World Health Organization, an estimated 17.9 million people die from cardiovascular diseases each year, representing 31% of all global deaths. Continuous non-invasive arterial pressure (CNAP) is essential for the management of cardiovascular diseases. However, it is difficult to achieve long-term CNAP monitoring with the daily use of current devices due to irritation of the skin as well as the lack of motion artifacts suppression. Here, we report a high-performance skin-like optoelectronic system integrated with ultra-thin flexible circuits to monitor CNAP. We introduce a theoretical model via the virtual work principle for predicting the precise blood pressure and suppressing motion artifacts, and propose optical difference in the frequency domain for stable optical measurements in terms of skin-like devices. We compare the results with the blood pressure acquired by invasive (intra-arterial) blood pressure monitoring for >1500 min in total on 44 subjects in an intensive care unit. The maximum absolute errors of diastolic and systolic blood pressure were ±7/±10 mm Hg, respectively, in immobilized, and ±10/±14 mm Hg, respectively, in walking scenarios. These strategies provide advanced blood pressure monitoring techniques, which would directly address an unmet clinical need or daily use for a highly vulnerable population. 相似文献
4.
Chao Xue Jian-Ping Liu Qing Li Jun-Fei Wu Shan-Qing Yang Qi Liu Cheng-Gang Shao Liang-Cheng Tu Zhong-Kun Hu Jun Luo 《国家科学评论(英文版)》2020,7(12):1803
The Newtonian gravitational constant G, which is one of the most important fundamental physical constants in nature, plays a significant role in the fields of theoretical physics, geophysics, astrophysics and astronomy. Although G was the first physical constant to be introduced in the history of science, it is considered to be one of the most difficult to measure accurately so far. Over the past two decades, eleven precision measurements of the gravitational constant have been performed, and the latest recommended value for G published by the Committee on Data for Science and Technology (CODATA) is (6.674 08 ± 0.000 31) × 10−11 m3 kg−1 s−2 with a relative uncertainty of 47 parts per million. This uncertainty is the smallest compared with previous CODATA recommended values of G; however, it remains a relatively large uncertainty among other fundamental physical constants. In this paper we briefly review the history of the G measurement, and introduce eleven values of G adopted in CODATA 2014 after 2000 and our latest two values published in 2018 using two independent methods. 相似文献
5.
R&D国际化是经济全球化不断发展的必然要求.通过对R&D国际化的国内外研究现状进行评述,总结了近年来国内外开展R&D国际化研究的特点及不足,提出我国今后努力的方向. 相似文献
6.
我国高新区产业集聚测度方法研究 总被引:1,自引:0,他引:1
基于带有内生技术进步的科布——道格拉斯生产函数,本研究探讨了我国高新区生产要素地理集中及其规模收益变化的测度方法,对高新区及其所在城市1991-2004年面板数据的实证研究结果表明,我国高新区的产业地理集中已初具规模,但要素投入的产出弹性整体呈下降趋势。 相似文献
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采用多维尺度分析法,通过考察26位专家对组织文化结构的空间认知模式,确定了一个五维度的组织文化度量模型,包括人际和谐、开放创新、短期结果、竞争效率和严格控制。我们还在6家组织中进行了问卷调查,获得607份有效问卷。通过对数据进行验证性因子分析,初步建立了相应的测量量表(DOCQ)。 相似文献
9.
智力资本及其测度研究 总被引:19,自引:0,他引:19
在知识经济条件下,企业智力资本已成为企业最重要的资源。在剖析智力资本概念和内涵的基础上,结合企业智力资本管理模型,提出了基于价值形式的整体存量测度、非价值形式的分量测试以及存量对比与转换式的流量测度的智力资本测度思路和框架。 相似文献
10.