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Teaching Reform and Practice of Statistics Courses in Big Data Management and Applications Major in the Context of New Quality Productivity
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作者 Tinghui Huang Junchao Dong Liang Min 《Journal of Contemporary Educational Research》 2025年第2期23-31,共9页
In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social developmen... In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social development.Consequently,many domestic universities have introduced majors or courses related to big data.Among these,the Big Data Management and Applications major stands out for its interdisciplinary approach and emphasis on practical skills.However,as an emerging field,it has not yet accumulated a robust foundation in teaching theory and practice.Current instructional practices face issues such as unclear training objectives,inconsistent teaching methods and course content,insufficient integration of practical components,and a shortage of qualified faculty-factors that hinder both the development of the major and the overall quality of education.Taking the statistics course within the Big Data Management and Applications major as an example,this paper examines the challenges faced by statistics education in the context of emerging productive forces and proposes corresponding improvement measures.By introducing innovative teaching concepts and strategies,the teaching system for professional courses is optimized,and authentic classroom scenarios are recreated through illustrative examples.Questionnaire surveys and statistical analyses of data collected before and after the teaching reforms indicate that the curriculum changes effectively enhance instructional outcomes,promote the development of the major,and improve the quality of talent cultivation. 展开更多
关键词 New quality productivity Big data Compound talents statistics course Teaching examples
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Research on Teaching Practice and Strategies of Probability and Statistics Thinking in Middle Schools Empowered by Modern Educational Technology
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作者 Jin He Jiangtao Yu Zhaoyuan Zhang 《Journal of Contemporary Educational Research》 2025年第11期55-61,共7页
With the implementation of General Senior High School Mathematics Curriculum Standards(2017 Edition,Revised in 2020),probability and statistics,as important carriers of the core mathematical competencies“mathematical... With the implementation of General Senior High School Mathematics Curriculum Standards(2017 Edition,Revised in 2020),probability and statistics,as important carriers of the core mathematical competencies“mathematical modeling”and“data analysis,”have increasingly highlighted their educational value.By summarizing the historical evolution of probability and statistics thinking and combining with teaching practice cases,this study explores its unique role in cultivating students’core mathematical competencies.The research proposes a project-based teaching strategy relying on real scenarios and empowered by technology.Through cases,it demonstrates how to use modern educational technology to realize the whole-process exploration of data collection,model construction,and conclusion verification,so as to promote the transformation of middle school probability and statistics teaching from knowledge imparting to competency development,and provide a practical reference for curriculum reform. 展开更多
关键词 Probability and statistics Core competencies Modern educational technology Project-based learning Teaching strategies
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Exploration on the Ideological and Political Construction Path of the“Probability Theory and Mathematical Statistics”Course
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作者 Qianlong Dang Xiaofeng Yang Wenliang Wu 《Journal of Contemporary Educational Research》 2025年第10期85-91,共7页
This paper focuses on the ideological and political construction of the course“Probability Theory and Mathematical Statistics.”Aiming at the current situation in teaching where emphasis is placed on knowledge impart... This paper focuses on the ideological and political construction of the course“Probability Theory and Mathematical Statistics.”Aiming at the current situation in teaching where emphasis is placed on knowledge imparting while value guidance is neglected,and combined with the requirements of ideological and political education policies in the new era,this paper explores the integration path between professional courses and ideological and political education.Through literature analysis,case comparison,and empirical research,the study proposes a systematic implementation plan covering the design of teaching objectives,the reconstruction of teaching content,and the optimization of the evaluation system.The purpose is to cultivate students’sense of social responsibility and innovative awareness by excavating the ideological and political elements in mathematics.The research results provide practical reference for colleges and universities to deepen the reform of ideological and political education in courses,and promote the implementation of the fundamental task of fostering virtue through education in STEM education. 展开更多
关键词 Probability theory Mathematical statistics Ideological and political education in courses Fostering virtue through education Construction path
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Reservoir parameter inversion based on weighted statistics 被引量:3
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作者 桂金咏 高建虎 +3 位作者 雍学善 李胜军 刘炳杨 赵万金 《Applied Geophysics》 SCIE CSCD 2015年第4期523-532,627,628,共12页
Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and ideal... Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and idealized models increases the uncertainties of the inversion result. Thus, we propose an inversion method that is different from traditional statistical rock physics modeling. First, we use deterministic and stochastic rock physics models considering the uncertainties of elastic parameters obtained by prestack seismic inversion and introduce weighting coefficients to establish a weighted statistical relation between reservoir and elastic parameters. Second, based on the weighted statistical relation, we use Markov chain Monte Carlo simulations to generate the random joint distribution space of reservoir and elastic parameters that serves as a sample solution space of an objective function. Finally, we propose a fast solution criterion to maximize the posterior probability density and obtain reservoir parameters. The method has high efficiency and application potential. 展开更多
关键词 Reservoir parameters INVERSION weighted statistics Bayesian framework stochastic simulation
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Wave statistics for ship seakeeping in China offshore 被引量:1
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作者 刘首华 牟林 +3 位作者 王兴 陈长霖 岳心阳 高志刚 《Marine Science Bulletin》 CAS 2014年第2期1-12,共12页
Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptab... Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptability prediction model. The observations from coastal stations, buoys, altimeters and volunteer ships that cover from 1993 to 2011 were interpolated into miller Ion-lat grids by using bilinear method and the analytical fields of ocean waves were given. By using optimal interpolation, the analysis wave fields were assimilated into the WAVEWATCH III (WW3) simulation results. From the assimilated results, the wave rose statistics, the wave height of muitiyear return period and the extreme 2-D wave spectrum are related to the ship seakeeping were calculated. Finally, the wave statistics in China offshore were analyzed in detail. 展开更多
关键词 ocean waves statistical characteristics ship seakeeping shipenvironmental adaptability
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Channel capacity and digital modulation schemes in correlated Weibull fading channels with nonidentical statistics 被引量:2
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作者 Xiao Hailin Nie Zaiping Yang Shiwen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期205-209,共5页
The novel closed-form expressions for the average channel capacity of dual selection diversity is presented, as well as, the bit-error rate (BER) of several coherent and noncoherent digital modulation schemes in the... The novel closed-form expressions for the average channel capacity of dual selection diversity is presented, as well as, the bit-error rate (BER) of several coherent and noncoherent digital modulation schemes in the correlated Weibull fading channels with nonidentical statisticS. The results are expressed in terms of Meijer's Gfunction, which can be easily evaluated numerically. The simulation results are presented to validate the proposed theoretical analysis and to examine the effects of the fading severity on the concerned quantities. 展开更多
关键词 Average channel capacity Weibull fading channels Bit-error rate Digital modulation Nonidentical statistics.
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Analysis of linear weighted order statistics CFAR algorithm 被引量:1
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作者 孟祥伟 关键 何友 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期232-236,共5页
CFAR technique is widely used in radar targets detection fields. Traditional algorithm is cell averaging (CA), which can give a good detection performance in a relatively ideal environment. Recently, censoring techniq... CFAR technique is widely used in radar targets detection fields. Traditional algorithm is cell averaging (CA), which can give a good detection performance in a relatively ideal environment. Recently, censoring technique is adopted to make the detector perform robustly. Ordered statistic (OS) and trimmed mean (TM) methods are proposed. TM methods treat the reference samples which participate in clutter power estimates equally, but this processing will not realize the effective estimates of clutter power. Therefore, in this paper a quasi best weighted (QBW) order statistics algorithm is presented. In special cases, QBW reduces to CA and the censored mean level detector (CMLD). 展开更多
关键词 RADAR DETECTION CFAR order statistics.
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基于statistics的316L不锈钢柠檬酸钝化工艺正交实验数据分析 被引量:1
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作者 夏明六 韩成树 《热加工工艺》 CSCD 北大核心 2012年第18期42-44,48,共4页
从statistics的数据处理能力出发,运用统计学知识对316L不锈钢柠檬酸钝化工艺参数正交实验数据进行分析,找出钝化速率的主要影响因素;柠檬酸含量5wt%、双氧水含量5wt%、钝化时间60 min为最佳的实验方案;双氧水含量为钝化速率的主要影响... 从statistics的数据处理能力出发,运用统计学知识对316L不锈钢柠檬酸钝化工艺参数正交实验数据进行分析,找出钝化速率的主要影响因素;柠檬酸含量5wt%、双氧水含量5wt%、钝化时间60 min为最佳的实验方案;双氧水含量为钝化速率的主要影响因素。 展开更多
关键词 statistics 316L不锈钢 柠檬酸 数据分析
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Identification of Sewage Monitoring Data Based on Mathematical Statistics
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作者 万玉山 邹涛 +3 位作者 李大伟 温馨 沈梦 陈艳秋 《Agricultural Science & Technology》 CAS 2017年第4期656-659,共4页
In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, pro... In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, providing a set of technological process to identify the sewage monitoring data, which is convenient and simple. 展开更多
关键词 Mathematical statistics Monitoring data Technological process
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留学生Medical Statistics线上课程建设与远程教学的实践与思考
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作者 丁竞竞 钱炜春 +1 位作者 赵杨 张汝阳 《中国卫生统计》 CSCD 北大核心 2023年第6期942-945,949,共5页
受政治、经济和全球健康等因素影响,远程教育成为高等教育的一个发展趋势。新冠疫情防控期间,受出入境限制,未能返华的留学生一直以远程教学推进学业,成为其间持续进行远程教学最久的群体。本研究总结临床专业本科留学生主干课程Medical... 受政治、经济和全球健康等因素影响,远程教育成为高等教育的一个发展趋势。新冠疫情防控期间,受出入境限制,未能返华的留学生一直以远程教学推进学业,成为其间持续进行远程教学最久的群体。本研究总结临床专业本科留学生主干课程Medical Statistics的校级一流线上课程建设与教学实践,并比较了疫情前后,线下教学与远程教学的留学生期末考试成绩,发现远程教学成绩经历波动后逐渐稳定并接近传统线下教学。本文同时对效果影响因素进行了调研和分析,发现“充分学习和使用远程课程中丰富的资源”和“上网是否容易”是留学生学习效果的主要影响因素。提出建设丰富教学资源对促进医学统计学远程学习效果的重要影响,同时提出对策建议,以期进一步提高远程教学水平,服务高校现代化课程体系建设。 展开更多
关键词 线上课程建设 远程教学实践 Medical statistics 医学统计学 本科留学生
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中青年肺结核患者恐惧疾病进展的潜在剖面及影响因素分析
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作者 陈薇薇 邹圣强 +2 位作者 袁嘉 吴荣珍 施玲燕 《中国防痨杂志》 北大核心 2026年第1期84-93,共10页
目的:探究中青年肺结核患者恐惧疾病进展的潜在剖面类别,并分析不同类别的影响因素。方法:采用便利抽样法,选取2025年1—6月在苏州市第五人民医院住院的312例中青年肺结核患者作为调查对象,采用一般资料调查表、恐惧疾病进展简化量表、... 目的:探究中青年肺结核患者恐惧疾病进展的潜在剖面类别,并分析不同类别的影响因素。方法:采用便利抽样法,选取2025年1—6月在苏州市第五人民医院住院的312例中青年肺结核患者作为调查对象,采用一般资料调查表、恐惧疾病进展简化量表、一般自我效能感量表、慢性病治疗经济毒性功能评估综合评分量表、领悟社会支持量表、结核病污名感受量表进行调查。对中青年肺结核患者恐惧疾病进展进行潜在剖面分析,并通过单因素分析和多元logistic回归分析其影响因素。结果:中青年肺结核患者恐惧疾病进展可分为2个潜在剖面类别,即“低恐惧风险-疾病适应组”(184例,58.97%),其恐惧疾病进展简化量表平均得分为(28.19±5.41)分;以及“高恐惧风险-功能失调组”(128例,41.03%),其恐惧疾病进展简化量表平均得分为(41.65±5.20)分。多因素logistic回归分析显示,经济安全感(OR=0.894,95%CI:0.808~0.989)、家庭支持(OR=0.900,95%CI:0.835~0.970)是恐惧疾病进展的保护因素,而已婚(OR=2.410,95%CI:1.101~5.275)、新型农村合作医疗(OR=2.436,95%CI:1.083~5.481)、治疗阶段3~6个月(OR=2.628,95%CI:1.316~5.251)、治疗阶段>6个月(OR=4.621,95%CI:1.979~10.789)、经济压力与负担(OR=1.200,95%CI:1.081~1.331)、未来经济担忧(OR=1.157,95%CI:1.034~1.295)、自我负面感受(OR=1.086,95%CI:1.026~1.150)是导致患者归属于高恐惧风险组的危险因素。结论:中青年肺结核患者恐惧疾病进展水平具有明显的异质性,护士应根据分类特点制定相应干预策略。 展开更多
关键词 结核 恐惧 因素分析 统计学
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Single-channel speech enhancement method based on masking properties and minimum statistics
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作者 JiangXiaoping YaoTianren FuHua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第2期217-224,共8页
A single-channel speech enhancement method of noisy speech signals at very low signal-to-noise ratios is presented, which is based on masking properties of the human auditory system and power spectral density estimati... A single-channel speech enhancement method of noisy speech signals at very low signal-to-noise ratios is presented, which is based on masking properties of the human auditory system and power spectral density estimation of non stationary noise. It allows for an automatic adaptation in time and frequency of the parametric enhancement system, and finds the best tradeoff among the amount of noise reduction, the speech distortion, and the level of musical residual noise based on a criterion correlated with perception and SNR. This leads to a significant reduction of the unnatural structure of the residual noise. The results with several noise types show that the enhanced speech is more pleasant to a human listener. 展开更多
关键词 auditory property masking varying SNR estimation speech enhancement minimum statistics.
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云南省民族地区≥65岁老年人接受肺结核主动筛查的意愿及影响因素分析
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作者 唐顺定 许琳 +2 位作者 李玲 寸得娇 杨蕊 《中国防痨杂志》 北大核心 2026年第1期49-56,共8页
目的:评估云南省民族地区实施老年人肺结核主动筛查策略下肺结核筛查接受意愿及其影响因素,为提升主动筛查质量提供建议。方法:2023年1月1日至12月31日期间,采用分层随机抽样方法,选取云南省3个民族地区6个县(市)的12个乡镇/社区年龄≥6... 目的:评估云南省民族地区实施老年人肺结核主动筛查策略下肺结核筛查接受意愿及其影响因素,为提升主动筛查质量提供建议。方法:2023年1月1日至12月31日期间,采用分层随机抽样方法,选取云南省3个民族地区6个县(市)的12个乡镇/社区年龄≥65岁老年人开展肺结核主动筛查接受意愿问卷调查,共发放问卷1399份,收回有效问卷1395份,有效率为99.71%。结果:92.62%(1292/1395)的老年人愿意接受肺结核症状筛查,94.27%(1315/1395)的老年人愿意接受肺结核相关检查,90.18%(1258/1395)的老年人对于肺结核症状筛查和相关检查均愿意接受。肺结核主动筛查接受意愿显示,其他职业者主动筛查接受意愿是农业劳动者的9.157倍(95%CI:1.242~67.495);购买其他医保者主动筛查意愿是购买城乡居民医保者的4.098倍(95%CI:1.762~9.531);罹患至少1种疾病者主动筛查意愿是未患病者的1.767倍(95%CI:1.198~2.604);知晓“老年人更容易得肺结核”者主动筛查意愿是不知晓者的3.110倍(95%CI:2.101~4.603);家庭年人均医疗支出≤平均水平者的主动筛查意愿低于>平均水平者(OR=0.459,95%CI:0.313~0.674)。结论:现有政策下云南省民族地区≥65岁老年人群中接受肺结核主动筛查意愿高,应继续结合国家基本公共卫生服务项目在老年人群中开展肺结核主动筛查,提升筛查质量和效率,提高患者发现水平。 展开更多
关键词 老年人 结核 主动筛查 问卷调查 因素分析 统计学
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Using Monte Carlo Simulation Technology to Improve Intuitive Effect of Teaching Probability and Mathematical Statistics Course
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作者 万文应 夏庆 《科教导刊》 2015年第2期91-92,共2页
With the illustration of a specific problem, this paper demonstrates that using Monte Carlo Simulation technology will improve intuitive effect of teaching Probability and Mathematical Statistics course, and save inst... With the illustration of a specific problem, this paper demonstrates that using Monte Carlo Simulation technology will improve intuitive effect of teaching Probability and Mathematical Statistics course, and save instructors' effort as well.And it is estimated that Monte Carlo Simulation technology will be one of the major teaching methods for Probability and Mathematical Statistics course in the future. 展开更多
关键词 MONTE Carlo Simulation intuitive PROBABILITY and MATHEMATICAL statistics
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2000—2021年中国24岁及以下人群结核病疾病负担现状及趋势分析
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作者 孙晴 王小平 +3 位作者 杨小梅 韩瑞豪 顾烨秋 符剑 《中国防痨杂志》 北大核心 2026年第1期21-33,共13页
目的:分析2000—2021年中国24岁及以下人群结核病疾病负担情况及变化趋势,为24岁及以下人群结核病防控策略的制定提供参考依据。方法:从全球疾病负担数据库(GBD 2021)中提取中国2000—2021年24岁及以下人群结核病标化发病率、感染率、... 目的:分析2000—2021年中国24岁及以下人群结核病疾病负担情况及变化趋势,为24岁及以下人群结核病防控策略的制定提供参考依据。方法:从全球疾病负担数据库(GBD 2021)中提取中国2000—2021年24岁及以下人群结核病标化发病率、感染率、死亡率、伤残调整寿命年(DALYs),采用Joinpoint回归模型分析22年间中国24岁及以下人群结核病疾病负担变化趋势,各项指标的变化趋势以年度百分比(APC)和平均年度百分比(AAPC)进行描述。结果:2000—2021年,我国24岁及以下人群的结核病标化发病率、感染率、死亡率、DALYs率的年度均值分别为53.51/10万、29889.73/10万、4.92/10万和180.04/10万,降幅分别为54.16%、5.75%、81.46%和79.67%,均呈明显下降趋势(AAPC值分别为-3.639%、-0.301%、-7.745%和-7.317%);其中,标化感染率的下降幅度最低,且在2005—2010年和2015—2019年期间均呈阶段性上升趋势(从2005年的29446.97/10万上升至2010年的30057.59/10万,APC值为0.587%;从2015年的27918.13/10万上升至2019年的30567.83/10万,APC值为2.483%)。从年龄组看,结核病标化发病率、死亡率、DALYs率降幅最大的均是0~4岁组(分别为72.58%、95.79%、94.20%),均呈明显下降趋势(AAPC值分别为-5.970%、-14.058%和-12.670%);降幅最小的均是20~24岁组(AAPC值分别为-2.378%、-8.174%和-5.709%);而5~9、10~14、15~19、20~24岁组的结核感染变化率在2005—2010年和2015—2019年均呈阶段性上升趋势(分别从2005年的7010.40/10万、11768.47/10万、24312.79/10万、32324.53/10万上升至2010年的7334.07/10万、12575.43/10万、24748.90/10万、33308.53/10万,APC值分别为0.913%、1.685%、0.560%、0.812%;分别从2015年的6966.83/10万、11735.23/10万、22686.91/10万、30001.30/10万上升至2019年的8937.86/10万、15005.36/10万、25357.04/10万、32830.45/10万,APC值分别为6.852%、6.767%、3.071%、2.464%)。从性别来看,男性结核病患者的年均标化发病率、感染率、死亡率、DALYs率(分别为67.83/10万、31082.59/10万、7.03/10万、241.34/10万)均高于女性(分别为40.14/10万、28673.12/10万、3.07/10万、121.48/10万),且男性和女性患者4项指标均呈明显下降趋势(男性AAPC值分别为-3.396%、-0.288%、-7.221%、-6.724%,女性AAPC值分别为-4.082%、-0.317%、-8.880%、-8.452%),但男性患者的下降幅度(分别为51.74%、5.55%、79.08%、76.83%)均低于女性(分别为58.25%、6.02%、85.67%、84.23%);其中,男性和女性的结核病标化感染率在2005—2010年、2015—2019年期间均呈阶段性上升趋势(分别从2005年的30740.24/10万、28126.36/10万上升至2010年的31252.77/10万、28842.19/10万,APC值分别为0.492%和0.696%;分别从2015年的29110.34/10万、26708.01/10万上升至2019年的31696.74/10万、29408.98/10万,APC值分别为2.332%和2.637%)。结论:2000—2021年中国24岁及以下人群结核病疾病负担显著下降,但结核感染率仍较高,且下降速度缓慢。其中,女性结核病疾病负担虽低于男性,但其各指标的下降幅度均高于男性;20~24岁组的结核病疾病负担最高,其次是0~4岁组。未来我国仍需加强结核病防控力度,制定更有针对性的疫情防控策略。 展开更多
关键词 结核 青少年 疾病负担 模型 统计学 回归分析 流行病学研究
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肺结核患者的自律性现状及其影响因素分析
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作者 陈丽娜 丁丽麒 +1 位作者 何燕 陈丹萍 《中国防痨杂志》 北大核心 2026年第1期113-120,共8页
目的:调查肺结核患者的自律性现状分析其影响因素,为构建肺结核患者自律行为的干预措施提供参考依据。方法:采用便利抽样法,于2025年3—6月选取在同济大学附属上海市肺科医院结核科住院肺结核患者571例作为调查对象,使用一般资料、肺结... 目的:调查肺结核患者的自律性现状分析其影响因素,为构建肺结核患者自律行为的干预措施提供参考依据。方法:采用便利抽样法,于2025年3—6月选取在同济大学附属上海市肺科医院结核科住院肺结核患者571例作为调查对象,使用一般资料、肺结核自律性测评量表、结核病自我效能量表、领悟社会支持量表和结核病污名感受量表进行问卷调查。结果:纳入肺结核患者551例,肺结核患者自律性总得分为(112.40±14.71)分,相关性分析结果显示,肺结核患者自律性与结核病自我效能呈正相关(r=0.645,P<0.001),与领悟社会支持呈正相关(r=0.389,P<0.001),与结核病污名感受呈负相关(r=-0.089,P<0.05)。回归分析结果显示,女性(β=3.598,95%CI:1.652~5.544,P<0.001)、初中/高中/中专(β=3.480,95%CI:0.210~6.750,P=0.037)、大专及以上(β=10.016,95%CI:6.295~13.738,P<0.001)、常住地是农村(β=-2.387,95%CI:-4.593~-0.182,P=0.034)、结核病自我效能(β=0.792,95%CI:0.689~0.896,P<0.001)、结核病污名感受(β=0.094,95%CI:0.017~0.171,P=0.017)是肺结核患者自律性的影响因素。结论:肺结核患者自律性现状水平有待进一步提高,其自律性受性别、文化程度、常住地、结核病自我效能及结核病污名感受因素的影响。 展开更多
关键词 结核 自制力 因素分析 统计学 社会污名 自我效能 社会支持
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Weibull Statistics in Dielectric Strength of Oil-impregnated Pressboard under Ramped AC and DC Voltages
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作者 Mohammed Nedjar 《Journal of Energy and Power Engineering》 2013年第12期2388-2395,共8页
AC and DC breakdown tests were performed on large populations of oil-impregnated pressboard samples. The effect of voltage ramp rate on dielectric strength has been investigated. A statistical analysis of breakdown da... AC and DC breakdown tests were performed on large populations of oil-impregnated pressboard samples. The effect of voltage ramp rate on dielectric strength has been investigated. A statistical analysis of breakdown data was carried out using the Weibull distribution. The 90% confidence intervals of Weibull graphs were calculated. The study shows that dielectric strength and shape parameter change versus ramp rate. The variations are attributed to the size and number of defects. Discharges occur from the oil to the oil-pressboard interface and lead to breakdown. DC dielectric strength is larger than that corresponding to AC voltage. This is ascribed to the dissipated energy difference under the two types of field and the fatigue produced by the alternating voltage. This phenomenon is related to space charge. Under DC stress, dielectric strength is higher under negative polarity. It is assigned to the different quantities of space charge accumulated under the two polarities. 展开更多
关键词 Oil-impregnated pressboard dielectric strength Weibull statistics.
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面向远海场景的统计信道建模与性能分析
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作者 李瑞彤 林霏 +4 位作者 季翔 孙浩 张颖颖 李军 刘海英 《现代电子技术》 北大核心 2026年第1期15-20,共6页
目前对海洋通信的研究多集中于近海场景的信道建模,且较少考虑真实气象条件,针对远海场景的研究仍需进一步完善。为此,文中基于山东省黄海海域的实测气象数据,构建了利用海上蒸发波导现象的超视距统计信道模型,该模型采用有理数函数模... 目前对海洋通信的研究多集中于近海场景的信道建模,且较少考虑真实气象条件,针对远海场景的研究仍需进一步完善。为此,文中基于山东省黄海海域的实测气象数据,构建了利用海上蒸发波导现象的超视距统计信道模型,该模型采用有理数函数模型对海洋环境中电磁波的传播特性进行描述。同时,为提高模型的准确性,使用非线性最小二乘法对模型系数进行修正和优化。仿真分析表明,该信道模型在周边海域对电磁波传播路径损耗的预测更为精确,冬季和夏季的预测均方根误差均小于表面波导模型和自由空间模型,并在无人机辅助海上通信系统中表现出更为优异的性能。 展开更多
关键词 统计信道模型 海上通信 蒸发波导 实测气象数据 有理函数模型 超视距传输 抛物线方程 路径损耗
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Cancer statistics: updated cancer burden in China 被引量:151
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作者 Wanqing Chen 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第1期1-1,共1页
Cancer is a major public health issue in most of countries, including China. Accurate and valid information on cancer incidence, mortality, survival and relevant factors is irreplaceable for cancer prevention and cont... Cancer is a major public health issue in most of countries, including China. Accurate and valid information on cancer incidence, mortality, survival and relevant factors is irreplaceable for cancer prevention and control. Since the national program of cancer registry was launched by the Ministry of Health of China in 2008, the National Central Cancer Registry (NCCR) has been releasing the cancer incidence and mortality based on the data collected from cancer registries supported by the program. The cancer statistics provide current data from registered areas and aims to accurately reflect the cancer burden and epidemic in China. In 2014, the NCCR collected data for calendar year 2011 from 234 registries. After comprehensive quality' evaluation, data from 177 registries have been selected as sources of the reports reflecting cancer incidence and mortaliD, in the registration areas in 2011. These reports are the updated cancer statistics so far, covering much more registries and a hig population. 展开更多
关键词 Cancer statistics updated cancer burden in China
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中国数字消费水平测度与动态演进特征研究
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作者 冯帅 《统计与决策》 北大核心 2026年第1期85-90,共6页
数字消费水平测度研究对促进消费升级、扩大内需和推动中国经济高质量发展具有重要意义。文章基于2013—2022年省级面板数据,从消费环境、消费能力和消费活力3个维度构建数字消费水平评价指标体系,测算中国省域数字消费水平,并运用Kerne... 数字消费水平测度研究对促进消费升级、扩大内需和推动中国经济高质量发展具有重要意义。文章基于2013—2022年省级面板数据,从消费环境、消费能力和消费活力3个维度构建数字消费水平评价指标体系,测算中国省域数字消费水平,并运用Kernel密度估计、Dagum基尼系数及其分解方法,以及气泡图、小提琴图等数据可视化图形,分析中国省域数字消费水平的分布特征和动态演进趋势。结果表明:中国数字消费水平稳步提升,数字消费水平各指标的协调性整体有所提升,但仍有不少省份存在发展不协调问题;中国数字消费水平总体差异呈现“先缩小后扩大”的特征,主要来自地区间差异;东部和西部地区内部数字消费发展差异较大,分化现象明显,而中部和东北地区发展相对均衡。 展开更多
关键词 数字消费 统计测度 动态演变
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