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51.
激光粒度气象仪(Parsivel)是一种现代化的以激光为基础的光学测量系统。本文简要介绍了激光气象粒度仪(Parsivel)的仪器功能,数据传输以及软件功能模块;并借助激光气象粒度仪(Parsivel)在江西省人工增雨和人工防雹中成功应用的范例,探讨了激光粒度气象仪(Parsivel)在人工影响天气作业中的重要意义。  相似文献   
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53.
基于人工神经网络的研究生课程评价模型   总被引:2,自引:0,他引:2  
在研究生网上课程评价系统收集的大量数据基础上,构建了一种基于人工神经网络的多指标课程评价模型,并将网上调查的结果以连接权的方式赋予该评价模型进行训练。通过实际评价数据的验证,该模型能够准确地按照实际评价的过程进行工作。  相似文献   
54.
高效液相色谱法检测食品中人工合成甜菊糖甙   总被引:1,自引:0,他引:1  
建立了测定人工合成甜味剂甜菊糖甙的高效液相色谱分析方法.以C18柱为分离柱,流动相为20 mmol/L硫酸铵缓冲溶液(pH4.4)-乙腈(体积比为60∶40),流速为1.0 mL/min,柱温30℃,二极管阵列检测器进行检测,整个分离过程在15 min内完成.样品加标回收率为85%~96%,相对标准偏差小于3.5%.  相似文献   
55.
Artificial rugby union playing surface installation is increasing. This prospective cohort study aimed to examine the effect of playing surface on match injury types within 157 players of two UK professional rugby union clubs playing 209 matches (96 on artificial surfaces and 113 on grass) over three seasons. There was no difference in overall injury risk between the two playing surfaces with injury incidence on artificial 80.2 (CI 69.9–91.7) and on grass 81.9 per 1000 match-hours (CI 72.2–92.5), with an incidence rate ratio (RR) of 0.98 (CI 0.82–1.17). There was a higher rate of concussion (RR 0.52, CI 0.34 – 0.78) and chest injuries on grass (RR 0.26 CI 0.07, 0.95), and a higher rate of thigh haematoma (RR 2.25, CI 1.05–4.82) foot injuries (RR 4.12, CI 1.10, 15.40) and injury to players being tackled (RR 1.46, CI 1.00, 2.15) on artificial. Whilst there was no higher injury risk for matches played on artificial versus natural grass surfaces, the higher incidence of concussion and chest injury on grass, and the higher rate of foot injuries on artificial surfaces may be related to tackle and footwear-to-surface interface factors.  相似文献   
56.
The Fabry-Perot resonator (FPR) antenna has found wide applications in microwave and millimeter waves and recently attracted considerable interest, in this paper, a summary of planar and cylindrical structures, analytic models and research development is presented, and a comparison between these structures and analytic models is made, showing that such analytic models as the FP cavity mode, electromagnetic band gap (EBG) defect mode, transmission line mode, and leaky-wave mode are consistent when applied to analyze this type of resonator antenna. Some interesting topics under recent research, including dual or multi-band, improvement of gain bandwidth, low profile and beam control, are surveyed.  相似文献   
57.
Support is needed to promote problem-based learning (PBL) and to enhance critical thinking skills in discussion-based Internet forums. By advancing the capabilities of chat room and forum software, problem-based discussions for learning can be supported further in online learning environments. In this paper, the authors report on MALESAbrain, an intelligent learning tool. The model is built on the notions of threshold and knowledge weight from the discipline of machine learning. The model encourages learners to judge or critically evaluate the solutions posted by others before exploring further knowledge content. The system then sums up the judgment scores as its knowledge weight to pass the thresholds setup for ranking/arranging the learning issues. This constraint design, therefore, becomes a mechanism for critical thinking in a problem-based learning activity. MALESAbrain as a model helps transform the forum and chat room into rich learning discussion environments.  相似文献   
58.
Abstract

The dissemination of misinformation in health care and the sciences has become a growing concern over the last five years. Whether the false information is spread with malice or merely ignorance, researchers, providers, librarians, regulatory bodies, and internet platform providers have all begun taking steps to identify false information and halt its proliferation online. Some companies have begun looking at ways to apply artificial intelligence and machine learning to timely and widespread identification efforts. This column will investigate what technologies are currently being considered for addressing the misinformation crisis, discuss concerns over the application of such technologies, and consider methods for libraries to become more involved with the technological side of the issue.  相似文献   
59.
Business students taking data mining classes are often introduced to artificial neural networks (ANN) through point and click navigation exercises in application software. Even if correct outcomes are obtained, students frequently do not obtain a thorough understanding of ANN processes. This spreadsheet model was created to illuminate the roles of the following ANN parameters: weights, learning rates, threshold functions, and transformation functions. The spreadsheet ANN model project is given early in the semester, just after ANN is introduced. Students can see effects of ANN parameters as they make changes to spreadsheet model inputs, greatly enhancing discussion of ANN processes. After working with the spreadsheet model, students have expressed an appreciation for decisions based on patterns of historic data, and they like the ability to peek “behind the curtain” at processes of predictive software packages.  相似文献   
60.
本文介绍了交互式学习环境(ILE)教学系统及其现状,着重讨论了人工智能技术与方法在其中的应用,并阐述了人工智能的四个分支:智能代理、专家系统、知识表示、自然语言处理在ILE的应用。  相似文献   
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