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THEORY AND IMPLEMENTATION OF ICAI COGNITIVE MODEL BASED ON MEANING
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作者 何丕廉 侯越先 《Transactions of Tianjin University》 EI CAS 1999年第2期36-39,共4页
Cognitive models must be able to adapt the students learning behaviors dynamically.In our point of view,the processes of learning and understanding are,in nature,the procedure that gains the meaning of the object to b... Cognitive models must be able to adapt the students learning behaviors dynamically.In our point of view,the processes of learning and understanding are,in nature,the procedure that gains the meaning of the object to be learned.So,ICAI cognitive models should reflect the meaning structure of the domain knowledge in students mind.According to this view,we developed the meaning theory of Ludwig Wittgenstein,and proposed the concept of meaning conjoinism.On the basis of the meaning conjoinism we proposed a meaning oriented ICAI cognitive model and its corresponding teaching tactics.Furthermore,we developed an ICAI system named Thinking and the efficiency of our proposal has been demonstrated. 展开更多
关键词 meaning oriented meaning conjoinism cognitive model teaching tactics ICAI
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Photovoltaic Models Parameters Estimation Based on Weighted Mean of Vectors 被引量:1
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作者 Mohamed Elnagi Salah Kamel +1 位作者 Abdelhady Ramadan Mohamed F.Elnaggar 《Computers, Materials & Continua》 SCIE EI 2023年第3期5229-5250,共22页
Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the ... Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the non-linear nature of the photovoltaic cell,modeling solar cells and extracting their parameters is one of the most important challenges in this discipline.As a result,the use of optimization algorithms to solve this problem is expanding and evolving at a rapid rate.In this paper,a weIghted meaN oF vectOrs algorithm(INFO)that calculates the weighted mean for a set of vectors in the search space has been applied to estimate the parameters of solar cells in an efficient and precise way.In each generation,the INFO utilizes three operations to update the vectors’locations:updating rules,vector merging,and local search.The INFO is applied to estimate the parameters of static models such as single and double diodes,as well as dynamic models such as integral and fractional models.The outcomes of all applications are examined and compared to several recent algorithms.As well as the results are evaluated through statistical analysis.The results analyzed supported the proposed algorithm’s efficiency,accuracy,and durability when compared to recent optimization algorithms. 展开更多
关键词 Photovoltaic(PV)modules weIghted mean oF vectOrs algorithm(INFO) renewable energy static PV models dynamic PV models solar energy
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基于K-means算法的建筑群震害分析模型缩减方法
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作者 陈夏楠 张令心 +1 位作者 林旭川 王祺 《世界地震工程》 北大核心 2024年第1期72-79,共8页
基于建筑群模型和弹塑性时程分析的精细化城市震害模拟技术能够为防震减灾及应急救援决策提供必要的依据和参考。为了减小城市建筑群震害模拟的计算量和计算时间,本文提出一种基于聚类算法的建筑群模型缩减方法。该方法采用K-means聚类... 基于建筑群模型和弹塑性时程分析的精细化城市震害模拟技术能够为防震减灾及应急救援决策提供必要的依据和参考。为了减小城市建筑群震害模拟的计算量和计算时间,本文提出一种基于聚类算法的建筑群模型缩减方法。该方法采用K-means聚类算法,首先基于建筑结构属性向量对建筑群进行聚类,将相似的建筑结构聚为一组;然后从每组选取一个代表建筑组成建筑群缩减模型,通过减少需要分析的建筑结构数量来减少建筑群震害模拟的计算量。本文对传统的K-means算法进行改进,通过设定组内建筑结构的差异上限自动调整聚类分组数量;提出将具体地震动作用下结构地震损伤指数作为结构属性向量进行聚类,并通过算例对比分别采用两种缩减模型,即基于损伤指数聚类的缩减模型与基于结构力学模型参数聚类的缩减模型,计算结构损伤状态准确程度。对比结果表明:在聚类分组数量相同的情况下,基于损伤指数的分组明显优于基于模型参数的分组,采用模型缩减方法能够在保证足够计算精度前提下显著减少建筑群震害模拟计算量和计算时间。 展开更多
关键词 城市建筑群 K-meanS算法 模型缩减 结构模型参数 地震损伤指数
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Analytical and NumericalMethods to Study the MFPT and SR of a Stochastic Tumor-Immune Model
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作者 Ying Zhang Wei Li +1 位作者 Guidong Yang Snezana Kirin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2177-2199,共23页
The Mean First-Passage Time (MFPT) and Stochastic Resonance (SR) of a stochastic tumor-immune model withnoise perturbation are discussed in this paper. Firstly, considering environmental perturbation, Gaussian whiteno... The Mean First-Passage Time (MFPT) and Stochastic Resonance (SR) of a stochastic tumor-immune model withnoise perturbation are discussed in this paper. Firstly, considering environmental perturbation, Gaussian whitenoise and Gaussian colored noise are introduced into a tumor growth model under immune surveillance. Asfollows, the long-time evolution of the tumor characterized by the Stationary Probability Density (SPD) and MFPTis obtained in theory on the basis of the Approximated Fokker-Planck Equation (AFPE). Herein the recurrenceof the tumor from the extinction state to the tumor-present state is more concerned in this paper. A moreefficient algorithmof Back-Propagation Neural Network (BPNN) is utilized in order to testify the correction of thetheoretical SPDandMFPT.With the existence of aweak signal, the functional relationship between Signal-to-NoiseRatio (SNR), noise intensities and correlation time is also studied. Numerical results show that both multiplicativeGaussian colored noise and additive Gaussian white noise can promote the extinction of the tumors, and themultiplicative Gaussian colored noise can lead to the resonance-like peak on MFPT curves, while the increasingintensity of the additiveGaussian white noise results in theminimum of MFPT. In addition, the correlation timesare negatively correlated with MFPT. As for the SNR, we find the intensities of both the Gaussian white noise andthe Gaussian colored noise, as well as their correlation intensity can induce SR. Especially, SNR is monotonouslyincreased in the case ofGaussian white noisewith the change of the correlation time.At last, the optimal parametersin BPNN structure are analyzed for MFPT from three aspects: the penalty factors, the number of neural networklayers and the number of nodes in each layer. 展开更多
关键词 Stochastic tumor-immune model mean first-passage time stochastic resonance signal-to-noise ratio back-propagation neural network
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改进的RFM模型和K-means算法在会员分类中的应用研究
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作者 张利斌 《常州信息职业技术学院学报》 2024年第3期47-51,共5页
针对传统RFM模型用于会员分类会产生失真的问题,对RFM模型提出了改进,增加了客户关系长度和客户购买周期两个参数。同时针对传统的K-means算法存在的问题,提出了一种基于样本对象特征方差加权与中心初始化的K-means算法。利用改进的RFM... 针对传统RFM模型用于会员分类会产生失真的问题,对RFM模型提出了改进,增加了客户关系长度和客户购买周期两个参数。同时针对传统的K-means算法存在的问题,提出了一种基于样本对象特征方差加权与中心初始化的K-means算法。利用改进的RFM模型对会员进行分类,可以有效地提高分类效率。 展开更多
关键词 RFM模型 K-meanS聚类 会员分类
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Performance of CMIP6 models in simulating the dynamic sea level:Mean and interannual variance
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作者 Hongying Chen Zhuoqi He +1 位作者 Qiang Xie Wei Zhuang 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第1期34-40,共7页
本研究采用卫星测高数据与第六次国际耦合模式比较计划(CMIP6)海平面动力进行对比,重点针对40S-40N地区的动力海平面(DSL),评估了模式对其平均态与年际变率的综合模拟能力,结果表明,对于DSL平均态的模拟,模式与观测结果非常吻合,模式之... 本研究采用卫星测高数据与第六次国际耦合模式比较计划(CMIP6)海平面动力进行对比,重点针对40S-40N地区的动力海平面(DSL),评估了模式对其平均态与年际变率的综合模拟能力,结果表明,对于DSL平均态的模拟,模式与观测结果非常吻合,模式之间的差异较小.其中,副热带北大西洋是模拟偏差和模式间差异较为显著的区域,对于DSL年际变率的模拟,模式之间保持较高的一致性,但是,模式与观测结果存在明显差异,模式普遍低估了DSL的年际方差;其中,误差大值区域出现在副热带西边界流附近,模式分辨率会影响CMIP6对中小尺度海洋过程的重现能力,这可能是导致CMIP6历史模拟出现误差的原因之一. 展开更多
关键词 动力海平面 CMIP6 平均态 年际变率 模式分辨率
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Study of the Magnetocaloric Effect in La0.5Sm0.2Sr0.3Mn1-xFexO3 (x = 0 and 0.05) Manganites with the Mean-Field Theory
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作者 Amnah Alofi Salha Khadhraui 《Advances in Materials Physics and Chemistry》 CAS 2024年第7期113-122,共10页
In this paper, the magnetocaloric in La0.5Sm0.2Sr0.3Mn1-xFexO3 compounds with x = 0 (LSSMO) and x = 0.05 (LSSMFO) were simulated using mean field model theory. A strong consistency was observed between the theoretical... In this paper, the magnetocaloric in La0.5Sm0.2Sr0.3Mn1-xFexO3 compounds with x = 0 (LSSMO) and x = 0.05 (LSSMFO) were simulated using mean field model theory. A strong consistency was observed between the theoretical and experimental curves of magnetizations and magnetic entropy changes, −ΔSM(T). Based on the mean-field generated −ΔSM(T), the substantial Temperature-averaged Entropy Change (TEC) values reinforce the appropriateness of these materials for use in magnetic refrigeration technology within TEC (10) values of 1 and 0.57 J∙kg−1∙K−1under 1 T applied magnetic field. 展开更多
关键词 MANGANITES MAGNETIZATION Magnetocaloric Effect mean Field model SIMULATION
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电网需求侧资源动态分布式k-means聚类算法 被引量:1
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作者 黄静 饶尧 刘政 《大连交通大学学报》 CAS 2024年第2期109-114,共6页
为有效聚合电网需求侧资源,合理、高效利用电网资源,提出基于分布式k-means的电网需求侧资源动态聚类算法。通过基于置信半径的分布式k-means算法聚类采集到的电网需求侧资源数据,在模糊C均值进化神经网络中,以聚类得到的电网需求侧资... 为有效聚合电网需求侧资源,合理、高效利用电网资源,提出基于分布式k-means的电网需求侧资源动态聚类算法。通过基于置信半径的分布式k-means算法聚类采集到的电网需求侧资源数据,在模糊C均值进化神经网络中,以聚类得到的电网需求侧资源数据为输入向量,输出电网需求侧资源场景,依据场景存在概率,以电网侧资源日均峰谷差最小、DG消纳程度最高与日均负荷波动率最小为目标函数,以电网需求侧资源曲线波动率与负荷互补为约束条件,构建电网需求侧资源多场景聚类模型,经动态改变惯性因子(DCW)粒子群算法求解模型后,实现电网需求侧资源多场景聚类。试验结果表明:该方法可实现电网需求侧资源动态聚类,应用该方法聚类不同场景电网需求侧资源时的日负荷率较低,聚类效果较好,可满足实际电力需求侧资源动态聚类工作的需要。 展开更多
关键词 电网需求 侧资源 动态聚类 分布式 K-meanS算法 聚类模型
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基于狄利克雷多项式过程模型与K-means结合的菌群分析
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作者 彭显 贺建峰 《生物信息学》 2024年第1期47-57,共11页
群体分型是一种有助于更好的理解人类身心健康等复杂生物学问题的有效方法,聚类是一种为了对样本分组来降低复杂性的定义肠型的方法,而传统K-means聚类算法的K值选取无法确定,本文在传统K-means聚类算法的基础上进行了改进,并公开数据... 群体分型是一种有助于更好的理解人类身心健康等复杂生物学问题的有效方法,聚类是一种为了对样本分组来降低复杂性的定义肠型的方法,而传统K-means聚类算法的K值选取无法确定,本文在传统K-means聚类算法的基础上进行了改进,并公开数据集上进行了验证,实验表明改进算法能够解决K值选取无法确定的问题,且聚类结果的稳定性、准确性和聚类质量都得到显著提高。将改进后的模型运用于肠道菌群OTUs数据,发现不仅能够有效地区分2-型糖尿病患者样本间的相似性,而且能鉴定出影响菌群结构异质性最大的OTUs菌,为临床解决2-型糖尿病问题提供了一种新的思路。 展开更多
关键词 K-meanS算法 狄利克雷过程混合模型 菌群分析 群体分型 聚类
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The Meaning Construction of Idiom Based on Blending Model
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作者 Han Jianghua 《宏观语言学》 2019年第1期105-115,共11页
This paper studies and construes the meaning construction of idiom based on blending model,intending to use the blending model to reveal the meaning construction mechanism of idiom so as to make people understand that... This paper studies and construes the meaning construction of idiom based on blending model,intending to use the blending model to reveal the meaning construction mechanism of idiom so as to make people understand that the meaning of idiom is constructed through the non-compositional integrated approach.The study shows that the conceptual blending is a primary means of encoding the metaphorical meaning of idiom.It blends the concepts of different cognitive frames,through the cross-space mapping and projection,to form a new concept,which is the metaphorical meaning of idiom.The process of idiom’s meaning construction is essentially a semantic leap,thus,a process of frame-shifting.Moreover,the national cognitive and cultural models play a very important role in the process of meaning construction of idiom.The cognitive model provides a guiding for the meaning construction of idiom,and this guiding become a kind of reality induced by the cultural model eventually. 展开更多
关键词 IDIOM meaning CONSTRUCTION BLENDING model
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改进K-means聚类的噪声污染监测网络模型的设计与研究
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作者 王慧 王凯文 +1 位作者 吴彦昕 温雨 《自动化应用》 2024年第16期266-268,共3页
为有效优化城市噪声监测网络,最小化监测点数量,提出了一种改进K-means聚类的噪声污染监测网络模型。通过计算轮廓系数以改进K值,从而改进K-means聚类算法,建立K-means聚类模型,并根据聚类结果的类质心位置确定监测点位置坐标,得到优化... 为有效优化城市噪声监测网络,最小化监测点数量,提出了一种改进K-means聚类的噪声污染监测网络模型。通过计算轮廓系数以改进K值,从而改进K-means聚类算法,建立K-means聚类模型,并根据聚类结果的类质心位置确定监测点位置坐标,得到优化的监测网络布局。结果表明,该模型在保证监测结果准确性和全面性的同时,有效减少了监测点的数量,从而降低了监测成本。 展开更多
关键词 噪声污染 K-meanS聚类 监测网络模型
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A Study of EM Algorithm as an Imputation Method: A Model-Based Simulation Study with Application to a Synthetic Compositional Data
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作者 Yisa Adeniyi Abolade Yichuan Zhao 《Open Journal of Modelling and Simulation》 2024年第2期33-42,共10页
Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear mode... Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear model is the most used technique for identifying hidden relationships between underlying random variables of interest. However, data quality is a significant challenge in machine learning, especially when missing data is present. The linear regression model is a commonly used statistical modeling technique used in various applications to find relationships between variables of interest. When estimating linear regression parameters which are useful for things like future prediction and partial effects analysis of independent variables, maximum likelihood estimation (MLE) is the method of choice. However, many datasets contain missing observations, which can lead to costly and time-consuming data recovery. To address this issue, the expectation-maximization (EM) algorithm has been suggested as a solution for situations including missing data. The EM algorithm repeatedly finds the best estimates of parameters in statistical models that depend on variables or data that have not been observed. This is called maximum likelihood or maximum a posteriori (MAP). Using the present estimate as input, the expectation (E) step constructs a log-likelihood function. Finding the parameters that maximize the anticipated log-likelihood, as determined in the E step, is the job of the maximization (M) phase. This study looked at how well the EM algorithm worked on a made-up compositional dataset with missing observations. It used both the robust least square version and ordinary least square regression techniques. The efficacy of the EM algorithm was compared with two alternative imputation techniques, k-Nearest Neighbor (k-NN) and mean imputation (), in terms of Aitchison distances and covariance. 展开更多
关键词 Compositional Data Linear Regression model Least Square Method Robust Least Square Method Synthetic Data Aitchison Distance Maximum Likelihood Estimation Expectation-Maximization Algorithm k-Nearest Neighbor and mean imputation
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基于K-means-LSTM模型的证券股价预测
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作者 肖田田 《科技和产业》 2024年第3期210-215,共6页
鉴于股票数据具有非平稳、非线性等特征,传统的统计模型无法精准预测股票价格的未来趋势。针对这个问题,构建一种混合深度学习方法来提高股票预测性能。首先,通过将距离算法修改为DTW(动态时间归整),令K-means聚类算法拓展为更适用于时... 鉴于股票数据具有非平稳、非线性等特征,传统的统计模型无法精准预测股票价格的未来趋势。针对这个问题,构建一种混合深度学习方法来提高股票预测性能。首先,通过将距离算法修改为DTW(动态时间归整),令K-means聚类算法拓展为更适用于时间序列数据的K-means-DTW,聚类出价格趋势相似的证券;然后,通过聚类数据来训练LSTM(长短时记忆网络)模型,以实现对单支股票价格的预测。实验结果表明,混合模型K-means-LSTM表现出更好的预测性能,其预测精度和稳定性均优于单一LSTM模型。 展开更多
关键词 股票价格预测 K-meanS DTW(动态时间归整) K-means-LSTM(K均值-长短时记忆网络)混合模型
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基于K-means算法的跨国零售商客户细分研究
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作者 崔雯 李剑锋 《中国商论》 2024年第9期37-40,共4页
随着经济全球化及大数据技术的蓬勃发展,跨国零售商之间的竞争日益激烈,根据客户特征进行客户细分,协助客户进行个性化的服务体验,有利于跨国零售商实现精准营销和高效的客户关系管理。为了提高客户细分的精度,本文提出一种基于RFM模型... 随着经济全球化及大数据技术的蓬勃发展,跨国零售商之间的竞争日益激烈,根据客户特征进行客户细分,协助客户进行个性化的服务体验,有利于跨国零售商实现精准营销和高效的客户关系管理。为了提高客户细分的精度,本文提出一种基于RFM模型的K-means聚类算法,使用簇内误方差(SSE)和轮廓系数(Silhouette Coefficient)计算聚类个数,优化K值选取。本文选取一家跨国零售商的数据进行实证检验,对细分后的结果进行特征分析,将客户划分为核心型客户、维护型客户和风险型客户三种类别,并为不同客户群体提供差异化营销策略,仅供参考。 展开更多
关键词 K-meanS RFM模型 跨国零售商 客户细分 聚类算法
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Mean shift algorithm based on fusion model for head tracking
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作者 安国成 高建坡 吴镇扬 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期299-302,共4页
To solve the mismatch between the candidate model and the reference model caused by the time change of the tracked head, a novel mean shift algorithm based on a fusion model is provided. A fusion model is employed to ... To solve the mismatch between the candidate model and the reference model caused by the time change of the tracked head, a novel mean shift algorithm based on a fusion model is provided. A fusion model is employed to describe the tracked head by sampling the models of the fore-head and the back-head under different situations. Thus the fusion head reference model is represented by the color distribution estimated from both the fore- head and the back-head. The proposed tracking system is efficient and it is easy to realize the goal of continual tracking of the head by using the fusion model. The results show that the new tracker is robust up to a 360°rotation of the head on a cluttered background and the tracking precision is improved. 展开更多
关键词 mean shift head tracking kernel density estimate fusion model
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应用K-MEANS聚类的数据驱动产品创新模型研究 被引量:1
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作者 李月恩 张舒青 张伽诚 《设计》 2023年第3期10-13,共4页
为了适应互联网技术的发展,使设计创新结果更好地满足用户需求,研究数据方式对设计创新的驱动作用。通过文献综述介绍数据驱动产品创新的基本特征,应用K-Means聚类方法构建数据驱动产品创新模型,根据模型分析结果指导产品设计。构建K-Me... 为了适应互联网技术的发展,使设计创新结果更好地满足用户需求,研究数据方式对设计创新的驱动作用。通过文献综述介绍数据驱动产品创新的基本特征,应用K-Means聚类方法构建数据驱动产品创新模型,根据模型分析结果指导产品设计。构建K-Means聚类的数据驱动产品创新模型,并应用该模型设计一款儿童陪伴机器人。使用本模型指导产品创新具有缩短产品开发时间、减少设计资源投入、提高产品设计效率等优点,有助于提高产品创新内容质量。 展开更多
关键词 产品创新 数据驱动设计 创新模型 K-meanS聚类 陪伴机器人设计
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Relativistic Consistent Angular-Momentum Projected Shell-Model: Relativistic Mean Field 被引量:3
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作者 LIYan-Song LONGGui-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期429-434,共6页
We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method... We develop a relativistic nuclear structure model, relativistic consistent angular-momentum projected shell-model (RECAPS), which combines the relativistic mean-field theory with the angular-momentum projection method. In this new model, nuclear ground-state properties are first calculated consistently using relativistic mean-field (RMF) theory. Then angular momentum projection method is used to project out states with good angular momentum from a few important configurations. By diagonalizing the hamiltonian, the energy levels and wave functions are obtained. This model is a new attempt for the understanding of nuclear structure of normal nuclei and for the prediction of nuclear properties of nuclei far from stability. In this paper, we will describe the treatment of the relativistic mean field. A computer code, RECAPS-RMF, is developed. It solves the relativistic mean field with axial-symmetric deformation in the spherical harmonic oscillator basis. Comparisons between our calculations and existing relativistic mean-field calculations are made to test the model. These include the ground-state properties of spherical nuclei <SUP>16</SUP>O and <SUP>208</SUP>Pb, the deformed nucleus <SUP>20</SUP>Ne. Good agreement is obtained. 展开更多
关键词 relativistic consistent angular-momentum projected shell-model relativistic mean field projected shell model PECAPS-RMF
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Joint Variable Selection of Mean-Covariance Model for Longitudinal Data 被引量:2
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作者 Dengke Xu Zhongzhan Zhang Liucang Wu 《Open Journal of Statistics》 2013年第1期27-35,共9页
In this paper we reparameterize covariance structures in longitudinal data analysis through the modified Cholesky decomposition of itself. Based on this modified Cholesky decomposition, the within-subject covariance m... In this paper we reparameterize covariance structures in longitudinal data analysis through the modified Cholesky decomposition of itself. Based on this modified Cholesky decomposition, the within-subject covariance matrix is decomposed into a unit lower triangular matrix involving moving average coefficients and a diagonal matrix involving innovation variances, which are modeled as linear functions of covariates. Then, we propose a penalized maximum likelihood method for variable selection in joint mean and covariance models based on this decomposition. Under certain regularity conditions, we establish the consistency and asymptotic normality of the penalized maximum likelihood estimators of parameters in the models. Simulation studies are undertaken to assess the finite sample performance of the proposed variable selection procedure. 展开更多
关键词 JOINT mean and COVARIANCE models Variable Selection Cholesky DECOMPOSITION Longitudinal Data Penalized MAXIMUM LIKELIHOOD Method
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Monthly Mean Temperature Prediction Based on a Multi-level Mapping Model of Neural Network BP Type 被引量:1
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作者 严绍瑾 彭永清 郭光 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第2期225-232,共8页
In terms of 34-year monthly mean temperature series in 1946-1979,the multi-level maPPing model of neural netWork BP type was applied to calculate the system's fractual dimension Do=2'8,leading tO a three-level... In terms of 34-year monthly mean temperature series in 1946-1979,the multi-level maPPing model of neural netWork BP type was applied to calculate the system's fractual dimension Do=2'8,leading tO a three-level model of this type with ixj=3x2,k=l,and the 1980 monthly mean temperture predichon on a long-t6rm basis were prepared by steadily modifying the weighting coefficient,making for the correlation coefficient of 97% with the measurements.Furthermore,the weighhng parameter was modified for each month of 1980 by means of observations,therefore constrcuhng monthly mean temperature forecasts from January to December of the year,reaching the correlation of 99.9% with the measurements.Likewise,the resulting 1981 monthly predictions on a long-range basis with 1946-1980 corresponding records yielded the correlahon of 98% and the month-tO month forecasts of 99.4%. 展开更多
关键词 Neural netWork BP-type multilevel mapping model Monthly mean temperature prediction
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基于K-Means聚类与灰色关联分析对玻璃文物成分的研究
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作者 徐惠 胡珊 +1 位作者 姚旭敏 储昭顺 《新疆师范大学学报(自然科学版)》 2023年第3期66-73,96,共9页
古代玻璃制品极易受埋藏环境的影响而风化,导致玻璃文物成分比例发生变化,从而影响对其类别的正确判断。文章针对古代玻璃制品的成分分析与鉴别问题,使用卡方检验、K-Means均值聚类、分层聚类、灰色关联等方法,构建卡方模型、BP神经网... 古代玻璃制品极易受埋藏环境的影响而风化,导致玻璃文物成分比例发生变化,从而影响对其类别的正确判断。文章针对古代玻璃制品的成分分析与鉴别问题,使用卡方检验、K-Means均值聚类、分层聚类、灰色关联等方法,构建卡方模型、BP神经网络模型、K-Means均值聚类模型、灰色关联分析等,运用Matlab、SPSS、Python等软件编程,研究了玻璃类型高钾与铅钡的分类依据,并对不同类别玻璃按照化学成分进行亚分类,分析了其化学成分的统计规律与关联关系。最后利用单因素方差分析法,检验了模型的合理性。 展开更多
关键词 卡方检验 K-means均值聚类 BP神经网络模型 灰色关联分析
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