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Incomplete nonextensive statistics and the zeroth law of thermodynamics
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作者 黄志福 欧聪杰 陈金灿 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期144-147,共4页
On the basis of the entropy of incomplete statistics (IS) and the joint probability factorization condition, two controversial problems existing in IS are investigated: one is what expression of the internal energy... On the basis of the entropy of incomplete statistics (IS) and the joint probability factorization condition, two controversial problems existing in IS are investigated: one is what expression of the internal energy is reasonable for a composite system and the other is whether the traditional zeroth law of thermodynamics is suitable for IS. Some new equivalent expressions of the internal energy of a composite system are derived through accurate mathematical calculation. Moreover, a self-consistent calculation is used to expound that the zeroth law of thermodynamics is also suitable for IS, but it cannot be proven theoretically. Finally, it is pointed out that the generalized zeroth law of thermodynamics for incomplete nonextensive statistics is unnecessary and the nonextensive assumptions for the composite internal energy will lead to mathematical contradiction. 展开更多
关键词 classical statistical mechanics theRMODYNAMICS probability theory
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Statistical variability and fragility assessment of ballistic perforation of steel plates for 7.62 mm AP ammunition 被引量:2
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作者 Mark G.Stewart Michael DNetherton 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期503-513,共11页
The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor range.The targets varied from 10 mm to 32 mm in thickness.The tests recorded pen... The paper describes field test results of 7.62×51 mm M61 AP(armour piercing) ammunition fired into mild steel targets at an outdoor range.The targets varied from 10 mm to 32 mm in thickness.The tests recorded penetration depth,probability of perforation(i.e.,complete penetration),muzzle and impact velocities,bullet mass,and plate yield strength and hardness.The measured penetration depth exhibited a variability of approximately±12%.The paper then compared ballistic test results with predictive models of steel penetration depth and thickness to prevent perforation.Statistical parameters were derived for muzzle and impact velocity,bullet mass,plate thickness,plate hardness,and model error.A Monte-Carlo probabilistic analysis was then developed to estimate the probability of plate perforation of 7.62 mm M61 AP ammunition for a range of impact velocities,and for mild steels,and High Hardness Armour(HHA) plates.This perforation fragility analysis considered the random variability of impact velocity,bullet mass,plate thickness,plate hardness,and model error.Such a probabilistic analysis allows for reliability-based design,where,for example,the plate thickness with 95% reliability(i.e.only 1 in 20 shots will penetrate the wall) can be estimated knowing the probabilistic distribution of perforation.Hence,it was found that the plate thickness to ensure a low 5% probability of perforation needs to be 11-15% thicker than required to have a 50/50 chance of perforation for mild steel plates.Plates would need to be 20-30% thicker if probability of perforation is reduced to zero. 展开更多
关键词 BALLISTICS probability statisticS Steel plates Armour steel AMMUNITION Experimental PERFORATION
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Load Statistics Priority Random Access Technology Based on Air-Space-Ground Integrated Network
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作者 Enze Li Hao Huan +1 位作者 Jingyu Wang Kunshan Yang 《Journal of Beijing Institute of Technology》 EI CAS 2024年第6期493-506,共14页
In today's world where everything is interconnected, air-space-ground integrated networks have become a current research hotspot due to their characteristics of high, long and wide area coverage. Given the constan... In today's world where everything is interconnected, air-space-ground integrated networks have become a current research hotspot due to their characteristics of high, long and wide area coverage. Given the constantly changing and dynamic characteristics of air and space networks, along with the sheer number and complexity of access nodes involved, the process of rapid networking presents substantial challenges. In order to achieve rapid and dynamic networking of air-space-ground integrated networks, this paper focuses on the study of methods for large-scale nodes to randomly access satellites. This paper utilizes a cross-layer design methodology to enhance the access success probability by jointly optimizing the physical layer and medium access control(MAC) layer aspects. Load statistics priority random access(LSPRA) technology is proposed.Experiments show that when the number of nodes is greater than 1 000, this method can also ensure stable access performance, providing ideas for the design of air-space-ground integrated network access systems. 展开更多
关键词 air-space-ground integrated network random access satellite-to-ground statistics priority access success probability
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Simulating the particle size distribution of rockfill materials based on its statistical regularity
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作者 阎宗岭 《Journal of Chongqing University》 CAS 2003年第2期20-23,共4页
The particle size distribution of rockfill is studied by using granular mechanics, mesomechanics and probability statistics to reveal the relationship of the distribution of particle size to that of the potential ener... The particle size distribution of rockfill is studied by using granular mechanics, mesomechanics and probability statistics to reveal the relationship of the distribution of particle size to that of the potential energy intensity before fragmentation, which finds out that the potential energy density has a linear relation to the logarithm of particle size and deduces that the distribution of the logarithm of particle size conforms to normal distribution because the distribution of the potential energy density does so. Based on this finding and by including the energy principle of rock fragmentation, the logarithm distribution model of particle size is formulated, which uncovers the natural characteristics of particle sizes on statistical distribution. Exploring the properties of the average value, the expectation, and the unbiased variance of particle size indicates that the expectation does notequal to the average value, but increases with increasing particle size and its ununiformity, and is always larger than the average value, and the unbiased variance increases as the ununiformity and geometric average value increase. A case study proves that the simulated results by the proposed logarithm distribution model accord with the actual data. It is concluded that the logarithm distribution model and Kuz-Ram model can be used to forecast the particle-size distribution of inartificial rockfill while for blasted rockfill, Kuz-Ram model is an option, and in combined application of the two models, it is necessary to do field tests to adjust some parameters of the model. 展开更多
关键词 ROCKFILL particle size probability statistics distribution characteristics
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Iterative static modeling of channelized reservoirs using history-matched facies probability data and rejection of training image
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作者 Kyungbook Lee Sungil Kim +2 位作者 Jonggeun Choe Baehyun Min Hyun Suk Lee 《Petroleum Science》 SCIE CAS CSCD 2019年第1期127-147,共21页
Most inverse reservoir modeling techniques require many forward simulations, and the posterior models cannot preserve geological features of prior models. This study proposes an iterative static modeling approach that... Most inverse reservoir modeling techniques require many forward simulations, and the posterior models cannot preserve geological features of prior models. This study proposes an iterative static modeling approach that utilizes dynamic data for rejecting an unsuitable training image(TI) among a set of TI candidates and for synthesizing history-matched pseudo-soft data. The proposed method is applied to two cases of channelized reservoirs, which have uncertainty in channel geometry such as direction, amplitude, and width. Distance-based clustering is applied to the initial models in total to select the qualified models efficiently. The mean of the qualified models is employed as a history-matched facies probability map in the next iteration of static models. Also, the most plausible TI is determined among TI candidates by rejecting other TIs during the iteration. The posterior models of the proposed method outperform updated models of ensemble Kalman filter(EnKF) and ensemble smoother(ES) because they describe the true facies connectivity with bimodal distribution and predict oil and water production with a reasonable range of uncertainty. In terms of simulation time, it requires 30 times of forward simulation in history matching, while the EnKF and ES need 9000 times and 200 times, respectively. 展开更多
关键词 History-matched facies probability map Training image rejection Iterative static modeling Channelized reservoirs Multiple-point statistics History matching
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Nonequilibrium Statistical Nature of Intergranular Brittle Fracture in Polycrystal
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作者 邵彬 邢修三 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期240-246,共7页
The brittle fracture probability and reliability are obtained in terms of dislocation mechanism of microcrack evolution. The statistical distribution functions and statistical deviations of elongation, strength, plast... The brittle fracture probability and reliability are obtained in terms of dislocation mechanism of microcrack evolution. The statistical distribution functions and statistical deviations of elongation, strength, plastic work, crack extension force, fracture foughness, critical and crack length, can be derived in a unified fashion. 展开更多
关键词 fracture probability rel iabi 1 ity fracture strength crack extension force fracture foughness statistical distribution function.
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基于Web of Science数据库竞争情报论文的统计分析
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作者 辛刚 袁晶 《现代情报》 CSSCI 2012年第7期169-172,共4页
以Web of Science数据库为检索来源,以主题检索的形式得出竞争情报的相关文献,运用文献计量学的方法对这些文献进行论文发表数量的年度分析,不同语种数量分析,不同国家地区分析,以及论文作者的分布和期刊来源分析。由此反映出WOS数据库... 以Web of Science数据库为检索来源,以主题检索的形式得出竞争情报的相关文献,运用文献计量学的方法对这些文献进行论文发表数量的年度分析,不同语种数量分析,不同国家地区分析,以及论文作者的分布和期刊来源分析。由此反映出WOS数据库竞争情报领域发表论文的状况,总结了该领域发表论文的一些特点,为以后相关内容的进一步研究提供借鉴。 展开更多
关键词 竞争情报 WEB of science 文献计量 统计分析
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基于Web of Science的我国生物技术文献的计量研究 被引量:9
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作者 王伟 吴信岚 《现代情报》 CSSCI 2011年第11期109-115,共7页
本文以JCR最新网络版(2009年)收录的38种生物技术源期刊的文献为研究对象,以Web of Science为研究工具,以文献研究和统计分析为主要研究方法,对10年来(2001-2010年)收录的生物技术领域的文献数量、类型、学科领域、来源期刊、科研机构... 本文以JCR最新网络版(2009年)收录的38种生物技术源期刊的文献为研究对象,以Web of Science为研究工具,以文献研究和统计分析为主要研究方法,对10年来(2001-2010年)收录的生物技术领域的文献数量、类型、学科领域、来源期刊、科研机构、被引频次等要素进行分析,并与美国生物技术研究的现状进行比较,为我国生物技术的研究与发展提供参考。 展开更多
关键词 WEB of science 生物技术 统计分析
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1999—2019年我国酱香白酒的研究概况——基于超星发现和Web of Science数据库中691篇文献统计分析 被引量:2
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作者 龙亚飞 张春林 《酿酒科技》 2020年第8期89-94,共6页
以超星发现和Web of Science数据库为数据源,设置时间跨度为1999至2019年,检索酱香型白酒这一研究领域的研究成果,经筛选后共得691篇中英文文献资料,以他们作为研究对象,分别从发展趋势、关键词、核心作者、核心机构、重要收录5方面统... 以超星发现和Web of Science数据库为数据源,设置时间跨度为1999至2019年,检索酱香型白酒这一研究领域的研究成果,经筛选后共得691篇中英文文献资料,以他们作为研究对象,分别从发展趋势、关键词、核心作者、核心机构、重要收录5方面统计分析,从而总结酱香型白酒这一领域的研究概况,为今后从事这一领域研究的人提供一定的参考。 展开更多
关键词 酱香白酒 超星发现 Web of science 文献统计 研究概况
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《Agricultural Sciences in China》近五年载文统计分析 被引量:1
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作者 贺文爱 《现代情报》 CSSCI 2011年第11期99-101,共3页
采用文献计量学方法,对2006-2010年《Agricultural Sciences in China》刊载的论文数量、作者合作、地区分布、基金论文及引文、普赖斯指数进行了统计分析,旨在为评估该期刊提供参考数据。
关键词 中国农业科学(英文版) 引文 统计分析
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低轨增强对北斗量化信号载噪比的影响
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作者 宋玉龙 杨春宝 《电子设计工程》 2025年第1期154-159,165,共7页
为了评估频点兼容下低轨增强对北斗信号接收的影响,从而指导接收机设计,通过概率统计理论推导了低轨增强下北斗信号的量化效应和载噪比损耗模型,并通过蒙特卡罗仿真给出了1~6 bit量化位宽下北斗信号的载噪比损耗与前端增益以及低轨增强... 为了评估频点兼容下低轨增强对北斗信号接收的影响,从而指导接收机设计,通过概率统计理论推导了低轨增强下北斗信号的量化效应和载噪比损耗模型,并通过蒙特卡罗仿真给出了1~6 bit量化位宽下北斗信号的载噪比损耗与前端增益以及低轨增强功率的关系,仿真与理论结果的一致性较好。实验结果表明,北斗信号最小载噪比损耗对应的最优前端增益与低轨增强功率无关,但最小载噪比衰减值会随着低轨信号功率的增强而增大,1~2 bit量化位宽下有明显的量化损耗,3 bit及以上量化位宽下北斗信号载噪比衰减特性基本一致。 展开更多
关键词 低轨增强 北斗 概率统计理论 量化效应 载噪比损耗模型 蒙特卡罗仿真
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基于统计损伤原理的岩石三轴压缩本构模型
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作者 焦晋楠 靳卫刚 《煤》 2025年第2期98-102,共5页
岩石在三轴压缩条件下的变形行为主要受到裂隙扩展与演化的影响。针对岩石在不同围压条件下的应力-应变曲线行为,分析了其闭合应力σ_(cc)、起裂应力σ_(ci)、扩容应力σ_(cd)、峰值应力σ_(c)随围压变化的演化规律。考虑到岩石峰后的... 岩石在三轴压缩条件下的变形行为主要受到裂隙扩展与演化的影响。针对岩石在不同围压条件下的应力-应变曲线行为,分析了其闭合应力σ_(cc)、起裂应力σ_(ci)、扩容应力σ_(cd)、峰值应力σ_(c)随围压变化的演化规律。考虑到岩石峰后的残余强度特征,建立了基于概率统计的损伤变量,并推导了基于统计损伤原理的岩石三轴压缩本构模型。结果表明:在围岩增加的条件下,岩石的特征应力也随之表现出增长过程。通过与试验数据进行对比分析,表明建立的本构模型可以有效描述岩石全阶段内的损伤演化规律和应力-应变曲线特征,验证了模型的合理性与可靠性。 展开更多
关键词 三轴压缩 裂隙扩展 本构模型 损伤力学 概率统计
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以案例牵引式教学法提升概率统计课程教学效果
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作者 王欣 《安顺学院学报》 2025年第1期115-120,共6页
在讨论案例牵引式教学法的教学价值与设计准备的基础上,通过三个案例阐述了该教学模式在概率统计课程教学中的应用,在教学过程中,通过贴切、生动、鲜活、新颖的案例,激发学生的学习兴趣,培养学生的数学思维,提升课堂教学效果。
关键词 案例牵引式教学 教学模式创新 概率统计教学
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《延安大学学报(自然科学版)》2020—2023年引文统计分析
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作者 毕伟 《延安大学学报(自然科学版)》 2025年第1期117-120,共4页
运用文献计量学引文分析法,对《延安大学学报(自然科学版)》2020—2023年共16期370篇论文的6617条引文进行统计分析。结果表明:引文率为100%;篇均引文量为17.88条,低于中国科技期刊的平均引文量19条;引文语种为中文和英文,分别占58.98%... 运用文献计量学引文分析法,对《延安大学学报(自然科学版)》2020—2023年共16期370篇论文的6617条引文进行统计分析。结果表明:引文率为100%;篇均引文量为17.88条,低于中国科技期刊的平均引文量19条;引文语种为中文和英文,分别占58.98%和41.02%;引文类型多样,其中期刊为83.62%,学位论文为6.20%,图书为4.99%;自引率为1.59%;普赖斯指数为39.14%,低于自然科学平均值50%。研究结果可为提高《延安大学学报(自然科学版)》的办刊质量和学术水平提供参考依据。 展开更多
关键词 《延安大学学报(自然科学版)》 引文统计分析 引文率 自引率 普赖斯指数
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Multi-fractal analysis of highway traffic data 被引量:2
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作者 商朋见 申金升 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期365-373,共9页
The purpose of the present study is to investigate the presence of multi-fractal behaviours in the traffic time series not only by statistical approaches but also by geometrical approaches. The pointwisc Hǒlder expon... The purpose of the present study is to investigate the presence of multi-fractal behaviours in the traffic time series not only by statistical approaches but also by geometrical approaches. The pointwisc Hǒlder exponent of a function is calculated by developing an algorithm for the numerical evaluation of HSlder exponent of time series. The traffic time series observed on the Beijing Yuquanying highway are analysed. The results from all these methods indicate that the traffic data exhibit the multi-fractal behaviour. 展开更多
关键词 fractals probability theory stochastic processes and statistics
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Heterogeneity of Some Cooperation/Competition Properties 被引量:1
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作者 徐秀莲 付春花 +1 位作者 刘爱芬 何大韧 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第4期253-256,共4页
We show that the heterogeneity index, which was proposed by Hu and Wang [Physica A 387 (2008) 3769], can be used to describe the disparity of the cooperation sharing or competition gain distributions, which is very ... We show that the heterogeneity index, which was proposed by Hu and Wang [Physica A 387 (2008) 3769], can be used to describe the disparity of the cooperation sharing or competition gain distributions, which is very important for understanding the dynamics of a cooperation/competition system. An analytical relation between the distribution parameters and the heterogeneity index is derived, which is in good agreement with the empirical results. Our theoretical and empirical analyses also show that the relation between the distribution parameters can be analytically derived from the so-called Zhang-Chang model [Physica A 360 (2006) 599; 383 (2007) 687). This strongly recommends a possibility to create a general dynamic cooperation/competition model. 展开更多
关键词 Environmental and Earth science statistical physics and nonlinear systems
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Noise composed of multiplication of two dichotomous noises
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作者 李静辉 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期1990-1997,共8页
In this paper, we introduce a noise which is composed of multiplication of two dichotomous noises, and derive the probability density and the statistical properties of this noise. The obtained results can help study t... In this paper, we introduce a noise which is composed of multiplication of two dichotomous noises, and derive the probability density and the statistical properties of this noise. The obtained results can help study the resonant activation phenomenon, the phenomenon of stochastic resonance, the transport of particles, and the nonequilibrium (phase) transition for the systems driven by this noise. 展开更多
关键词 Dichotomous noise probability density statistical properties
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Confidence Intervals for Relative Intensity of Collaboration(RIC)Indicators
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作者 Joel Emanuel Fuchs Lawrence Smolinsky Ronald Rousseau 《Journal of Data and Information Science》 CSCD 2022年第4期5-15,共11页
Purpose:We aim to extend our investigations related to the Relative Intensity of Collaboration(RIC)indicator,by constructing a confidence interval for the obtained values.Design/methodology/approach:We use Mantel-Haen... Purpose:We aim to extend our investigations related to the Relative Intensity of Collaboration(RIC)indicator,by constructing a confidence interval for the obtained values.Design/methodology/approach:We use Mantel-Haenszel statistics as applied recently by Smolinsky,Klingenberg,and Marx.Findings:We obtain confidence intervals for the RIC indicatorResearch limitations:It is not obvious that data obtained from the Web of Science(or any other database)can be considered a random sample.Practical implications:We explain how to calculate confidence intervals.Bibliometric indicators are more often than not presented as precise values instead of an approximation depending on the database and the time of measurement.Our approach presents a suggestion to solve this problem.Originality/value:Our approach combines the statistics of binary categorical data and bibliometric studies of collaboration. 展开更多
关键词 Contingency tables Confidence intervals Relative intensity of collaboration(RIC) Mantel-Haenszel statistics science of science
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基于比例导引法的鱼雷声自导导引弹道仿真分析
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作者 黄波 杨俊 《舰船科学技术》 北大核心 2024年第21期186-189,共4页
建立了鱼雷声自导比例导引法数学模型,并以某典型空间攻击态势为例进行弹道仿真,进而以命中概率和机动性作为评价准则、对比例导引法弹道的导引效果进行检验分析,结果表明:比例导引法弹道在鱼雷的机动性和命中概率两方面均优于尾追法弹... 建立了鱼雷声自导比例导引法数学模型,并以某典型空间攻击态势为例进行弹道仿真,进而以命中概率和机动性作为评价准则、对比例导引法弹道的导引效果进行检验分析,结果表明:比例导引法弹道在鱼雷的机动性和命中概率两方面均优于尾追法弹道,最后通过仿真计算给出了鱼雷在确定的命中概率下对目标速度的可攻性范围,相关结论可为鱼雷声自导的弹道优化和作战使用提供参考借鉴。 展开更多
关键词 声自导雷 比例导引法 弹道优化 蒙特卡洛统计模拟法 命中概率
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文化视角下的直觉教学:概率论与数理统计课程的教学创新研究
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作者 陈瑞 李贵平 《楚雄师范学院学报》 2024年第3期142-149,共8页
本文探讨了在概率论与数理统计课程中融合中国传统文化元素的创新教学方法,旨在推动教学创新并深化学生对课程内容的理解。针对传统教学方法过于侧重于理论知识传授的局限,研究提出通过引入中国古典哲学思想和文化元素,如《道德经》和... 本文探讨了在概率论与数理统计课程中融合中国传统文化元素的创新教学方法,旨在推动教学创新并深化学生对课程内容的理解。针对传统教学方法过于侧重于理论知识传授的局限,研究提出通过引入中国古典哲学思想和文化元素,如《道德经》和《易经》的故事,帮助学生在文化和哲学的层面上建立起对概率论概念的直觉理解。通过具体案例分析和创新教学方法的应用,展示了如何有效地结合传统文化理念和概率论教学,不仅丰富了教学内容,还激发了学生的学习兴趣,提高了他们解决实际问题的能力。研究还讨论了这种跨学科教学策略实施过程中的挑战,并提出了未来发展方向,强调该教学模式对于培养学生的数学技能以及增进对本土文化的理解和尊重具有重要意义,为学生的全面发展提供了支持。 展开更多
关键词 概率论与数理统计 课程思政 传统文化 直觉
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