copula function

  • 文章类型: Journal Article
    本研究使用家庭综合收入和消费调查(HIICS)的数据,研究了2006年至2016年巴基斯坦家庭层面的社会经济因素对卡路里摄入量和大量营养素组成的影响。通过应用基于copula的分解方法,它确定了关键驱动因素,如城市化,家庭大小,父系教育,收入,和种植,强调它们在饮食变化中的作用和对公共卫生的影响。这些发现对于了解营养变化和解决非传染性疾病至关重要。
    这项研究旨在评估人均总卡路里摄入量和从大量营养素(脂肪,蛋白质,和碳水化合物)在巴基斯坦的家庭层面。
    :横截面数据来自巴基斯坦统计局发布的2项国家级调查:2006年家庭综合经济调查(14,948户)和2016年家庭综合收入和消费调查(7842户)。参与者来自巴基斯坦所有4个省。基于copula的分解方法被应用于分解分布的10-y变化(平均值,中位数,和四分位数)人均总卡路里摄入量和从常量营养素中获得的卡路里。
    分解的估计结果表明,人均总卡路里摄入量平均和所考虑的四分位数增加了。从脂肪和碳水化合物中获得的卡路里增加了,而来自蛋白质的卡路里减少了,根据均值和四分位数的分布。所有结果变量的组成效应均为负,构成效应的主要驱动因素是城市化,家庭大小,父系教育,收入,和所有结果变量的培养。
    家庭规模和收入是人均总卡路里和大量营养素消费量增加的最重要的协变量,但是城市化,父系教育,和栽培对构图效果有负面影响。这些发现对于让研究人员了解国家一级的营养变化非常重要,因为饮食变化与非传染性疾病(如心脏病和肥胖症)的危险因素之间的相关性非常强。
    UNASSIGNED: This study examines the impact of socioeconomic factors on calorie intake and macronutrient composition at the household level in Pakistan from 2006 to 2016, using data from the Household Integrated Income and Consumption Survey (HIICS). By applying a copula-based decomposition method, it identifies key drivers such as urbanization, household size, paternal education, income, and cultivation, highlighting their roles in dietary changes and implications for public health. The findings are crucial for understanding nutritional shifts and addressing non-communicable diseases.
    UNASSIGNED: This study was conducted to assess the socioeconomic changes in total calorie intake per capita and calories obtained from macronutrients (fat, protein, and carbohydrates) at the household level in Pakistan.
    UNASSIGNED: : Cross-sectional data were taken from 2 national-level surveys published by the Pakistan Bureau of Statistics: the Household Integrated Economic Survey 2006 (14,948 households) and the Household Integrated Income and Consumption Survey 2016 (7842 households). Participants were from all 4 provinces of Pakistan. A copula-based decomposition method was applied to decompose the 10-y change in the distribution (mean, median, and quartiles) of the total calorie intake per capita and calories obtained from macronutrients.
    UNASSIGNED: The estimated results of decomposition revealed that total calorie intake per capita has increased on average and in the considered quartiles. The calories obtained from fat and carbohydrates have increased, whereas calories from protein have decreased, according to the distribution of the mean and quartile. The composition effect was negative for all outcome variables, and the main drivers of the composition effect were urbanization, household size, paternal education, income, and cultivation for all outcome variables.
    UNASSIGNED: Household size and income are the most important covariates in an increase of total calories per capita and consumption of macronutrients, but urbanization, paternal education, and cultivation contribute negatively to the composition effect. Such findings are very important to inform researchers about nutritional change at the national level because the correlation between dietary change and risk factors for noncommunicable diseases such as heart disease and obesity is very strong.
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  • 文章类型: Journal Article
    城市热浪的日益频繁发生已成为人类健康的重大威胁。为定量分析热浪特征变化,调查武汉市未来热浪重现期,中国,这项研究提取了9个热浪定义,并将其分为3个死亡风险水平,以识别和分析热浪的历史观察和未来预测。使用copula函数得出热浪严重程度和持续时间的联合分布,并分析共现重现期。结果证明如下。(1)随着温室气体排放浓度的增加,热浪的严重程度加剧,热浪的发生显著增加;此外,在每个排放情景中,较长持续时间的热浪与较高的风险水平相关。(2)温室气体排放浓度的增加导致每个风险级别的热浪共现重现期明显缩短。(3)在每个排放情景下的3个风险级别中,随着热浪严重程度的加剧和持续时间的增加,热浪的共现重现期变得更长。在气候变化的影响下,针对特定区域的热浪预警系统对于决策者降低人口中热相关死亡风险至关重要,尤其是弱势群体。
    The increasingly frequent occurrence of urban heatwaves has become a significant threat to human health. To quantitatively analyze changes in heatwave characteristics and to investigate the return periods of future heatwaves in Wuhan City, China, this study extracted 9 heatwave definitions and divided them into 3 mortality risk levels to identify and analyze historical observations and future projections of heatwaves. The copula functions were employed to derive the joint distribution of heatwave severity and duration and to analyze the co-occurrence return periods. The results demonstrate the following. (1) As the concentration of greenhouse gas emissions increases, the severity of heatwaves intensifies, and the occurrence of heatwaves increases significantly; moreover, a longer duration of heatwaves correlated with higher risk levels in each emission scenario. (2) Increasing concentrations of greenhouse gas emissions result in significantly shorter heatwave co-occurrence return periods at each level of risk. (3) In the 3 risk levels under each emission scenario, the co-occurrence return periods for heatwaves become longer as heatwave severity intensifies and duration increases. Under the influence of climate change, regional-specific early warning systems for heatwaves are necessary and crucial for policymakers to reduce heat-related mortality risks in the population, especially among vulnerable groups.
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  • 文章类型: Journal Article
    随着地球变暖,干旱日益频繁,对全球生态系统和人类社区提出了适应挑战。战略环境评估(SEA)和将适应战略纳入政策,plans,和计划(PPP)是增强气候适应能力和促进可持续发展的两个重要方法。这项研究开发了一种创新方法,通过量化未来温度升高的影响来加强干旱的SEA。通过利用多个数据源,将预测干旱事件的新方法集成到SEA过程中,包括大气再分析,重建,卫星观测,和模型模拟。我们使用陆地储水(TWS)异常识别了干旱条件,并应用了随机森林(RF)模型来解开干旱事件背后的驱动因素。然后,我们设定了两个全球变暖目标(2.0°C和2.5°C),并分析了三种共同的社会经济途径(SSP126,SSP370,SSP585)下的干旱变化。在2.0°C变暖的世界中,全球超过50%的地表将面临更多的干旱风险。随着0.5°C的额外增加,>60%的土地将容易进一步干旱升级。我们利用Copulas来建立干旱持续时间和严重程度的联合分布,估计双变量干旱灾害的联合重现期(JRP)。在热带和亚热带地区,在2.0°C变暖下,>33%的区域陆地表面和2.5°C变暖下>50%的JRP减少预计将超过一半。最后,我们预测了干旱事件对人口和国内生产总值(GDP)的影响。在三个SSP中,在SSP370下,在2.0°C变暖下,人口暴露最高,GDP暴露最小。干旱带来的全球GDP和人口风险预计将分别增加37%和24%。分别,随着变暖的继续。这项研究提高了SEA在解决干旱风险和脆弱性方面的准确性,支持气候适应规划和适应性战略。
    Droughts are increasingly frequent as the Earth warms, presenting adaptation challenges for ecosystems and human communities worldwide. A strategic environmental assessment (SEA) and the integration of adaptation strategies into policies, plans, and programs (PPP) are two important approaches for enhancing climate resilience and fostering sustainable development. This study developed an innovative approach to strengthen the SEA of droughts by quantifying the impacts of future temperature increases. A novel method for projecting drought events was integrated into the SEA process by leveraging multiple data sources, including atmospheric reanalysis, reconstructions, satellite-based observations, and model simulations. We identified drought conditions using terrestrial water storage (TWS) anomalies and applied a random forest (RF) model for disentangling the drivers behind drought events. We then set two global warming targets (2.0 °C and 2.5 °C) and analyzed drought changes under three shared socioeconomic pathways (SSP126, SSP370, SSP585). In a 2.0 °C warming world, over 50 % of the global surface will face increased drought risk. With an additional 0.5 °C increase, >60 % of the land will be prone to further drought escalation. We utilized copulas to build the joint distribution for drought duration and severity, estimating the joint return periods (JRP) for bivariate drought hazard. In tropical and subtropical regions, JRP reductions exceeding half are projected for >33 % of the regional land surface under 2.0 °C warming and for >50 % under 2.5 °C warming. Finally, we projected the impacts of drought events on population and gross domestic product (GDP). Among the three SSPs, under SSP370, population exposure is highest and GDP exposure is minimal under 2.0 °C warming. Global GDP and population risks from drought are projected to increase by 37 % and 24 %, respectively, as warming continues. This study enhances the accuracy of SEA in addressing drought risks and vulnerabilities, supporting climate-resilient planning and adaptive strategies.
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  • 文章类型: Journal Article
    We quantified the lag time of vegetation response to drought in the Pearl River basin (PRB) based on the standardized precipitation evapotranspiration index (SPEI) and normalized difference vegetation index (NDVI), and constructed a vegetation loss probability model under drought stress based on the Bayesian theory and two-dimensional joint distribution. We further quantitatively evaluated the spatial variations of loss probability of four vegetation types (evergreen broadleaf forest, mixed forest, grassland, and cropland) under different drought intensities. The results showed that the drought risk in eastern West River, the upper reaches of North River and East River, and southern Pearl River Delta was obviously higher than that in other regions during 1982-2020. The response time of vegetation to drought in high-altitude areas in the upper reaches of PRB (mostly<3 month) was generally shorter than that in low altitude areas (>8 month). Drought exacerbated the probability of vegetation loss, with higher vulnerability of mixed forest than the other three vegetation types. The loss probability of vegetation was lower in northwestern PRB than that in central PRB.
    基于标准化降水蒸散指数(SPEI)和归一化植被指数(NDVI),在网格尺度上定量识别珠江流域植被对干旱响应的滞后时间;基于贝叶斯理论和二维联合分布构建了干旱胁迫下植被损失的条件概率模型,定量评估了不同干旱情景下4种植被类型(常绿阔叶林、混交林、草地、耕地)的损失风险的空间分异性。结果表明: 1982—2020年间,西江流域东部、北江和东江流域上游以及珠三角南部地区的干旱风险明显高于研究区的其他区域;上游高海拔地区植被对干旱的响应时间(大多<3个月)通常小于低海拔地区(>8个月);干旱加剧了植被的脆弱性,其中,混交林在不同干旱强度下的损失概率大于其他3种植被类型,表现出更高的脆弱性;流域西北部植被损失概率低于流域中部地区。.
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  • 文章类型: Journal Article
    振动环境会导致微机电系统(MEMS)陀螺仪转子参数的漂移或变化,可能会影响他们的表现。为了提高MEMS陀螺仪的有效利用,本研究介绍了一种评估振动下参数退化可靠性的方法。我们分析了MEMS陀螺仪转子的工作原理,并研究了振动如何影响其参数。注重零偏差和比例因子作为关键绩效指标,我们使用分布假设方法建立了加速退化模型。然后,我们在各种振动条件下收集了这些参数的退化数据。使用Copula函数,我们建立了一种可靠性评估方法来评估振动下MEMS陀螺仪转子的零偏差和比例因子的退化,能够确定这些参数的可靠性。实验结果证实,增加应力水平导致减少故障时间和增加故障率的MEMS陀螺仪转子,在零偏差参数中观察到显著的变化。我们的评估方法有效地描述了MEMS陀螺仪转子的比例因子和零偏的可靠性随时间的变化,为MEMS陀螺仪的实际应用提供有价值的信息。
    Vibrational environments can cause drift or changes in Micro-Electro-Mechanical System (MEMS) gyroscope rotor parameters, potentially impacting their performance. To improve the effective use of MEMS gyroscopes, this study introduced a method for evaluating the reliability of parameter degradation under vibration. We analyzed the working principle of MEMS gyroscope rotors and investigated how vibration affects their parameters. Focusing on zero bias and scale factor as key performance indicators, we developed an accelerated degradation model using the distributional assumption method. We then collected degradation data for these parameters under various vibration conditions. Using the Copula function, we established a reliability assessment approach to evaluate the degradation of the MEMS gyroscope rotor\'s zero bias and scale factor under vibration, enabling the determination of reliability for these parameters. Experimental findings confirmed that increasing stress levels lead to reduced failure times and increased failure rates for MEMS gyroscope rotors, with significant changes observed in the zero bias parameter. Our evaluation method effectively characterizes changes in the reliability of the MEMS gyroscope rotor\'s scale factor and zero bias over time, providing valuable information for practical applications of MEMS gyroscopes.
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  • 文章类型: Journal Article
    重庆,作为长江上游的最后一道生态屏障,由于能源结构不平衡,限制了实现“双碳”目标。在通过Copula函数和Granger因果关系选择能量结构影响因素的基础上,构建了基于Sparrow算法的多维动态支持向量机模型(SSA-MFD-SVR-ARIMA),对绿色金融发展驱动下2021-2030年重庆市能源结构占比进行了预测,并获得了优化路径。新的研究结果证实,(1)绿色金融对优化重庆能源结构的相关贡献率为10.8%;(2)在绿色金融4.5%的持续增长下,到2030年,煤炭消费比重将达到40.03%,非化石能源消费占比将达到27%。这证实了重庆在2025年能够实现中央下达的《能源发展规划》。该研究从财务角度提出了包括绿色股权投资在内的四维优化路径,能源数字金融,为环境权益融资,发展产业基金。此外,我们提出了融资保障策略,创新,联动,以及该途径优化的保护机制。
    Chongqing, as the last ecological barrier of the Upper Yangtze River, is constrained to achieve \"dual carbon\" goals due to imbalanced energy structure. Based on selecting the energy structure influencing factors through Copula function and Granger causality, a multi-dimensional dynamic support vector machine model (SSA-MFD-SVR-ARIMA) by adopting sparrow algorithm was constructed to predict the proportion of Chongqing\'s energy structure from 2021 to 2030 under the drive of green finance development, and an optimization path was obtained. The novel findings confirm that (1) the correlated contribution rate of Green Finance to optimizing Chongqing\'s Energy Structure is 10.8 %; (2) under the sustained growth rate of Green Finance at 4.5 %, the proportion of coal consumption will reach 40.03 % by 2030, and non-fossil energy consumption will account for 27 %. It confirms that Chongqing can achieve the Energy Development Plan assigned by the Central Government in 2025. The research proposes a four-dimensional optimized pathway from a financial perspective that includes green equity investments, digital finance for energy, financing environmental rights and interests, and developing an industry fund. Furthermore, our put forward the safeguard strategies for financing, innovation, linkage, and protection mechanisms of this pathway optimization.
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  • 文章类型: Journal Article
    河流系统水质变量的准确预测对于相关管理人员识别潜在的水质恶化问题并及时采取对策至关重要。然而,在当今更为复杂的环境中,纯数据驱动的预测模型往往不足以处理水质高度变化的周期性。本研究通过结合先进的深度学习算法(即,具有因果推断的长短期记忆(LSTM)和告示者),时频分析,和不确定性量化。该框架已在亚洲最大的人工湖(即,丹江口水库,中国),2017年1月至2022年6月的6年监测数据。结果表明,基于因果推断和小波分解的预处理技术可以显著提高深度学习算法的性能。与单独的LSTM和Informer模型相比,小波耦合方法很好地减少了TN浓度的明显预测误差,24.39%,32.68%,平均最多可减少41.26%,标准偏差,和误差的最大值,分别。此外,设计了一种基于Copula函数和贝叶斯理论的后处理算法来量化预测的不确定性。在这个算法的帮助下,我们模型的每个确定性预测都可以对应于一系列可能的输出。95%的预测置信区间几乎涵盖了所有的观测值,这证明了预测的可靠性和鲁棒性。这项研究为在时间序列预测任务中应用先进的数据驱动方法提供了丰富的科学参考,并为水资源管理和类似项目提供了实用的方法框架。
    Accurate forecasting of water quality variables in river systems is crucial for relevant administrators to identify potential water quality degradation issues and take countermeasures promptly. However, pure data-driven forecasting models are often insufficient to deal with the highly varying periodicity of water quality in today\'s more complex environment. This study presents a new holistic framework for time-series forecasting of water quality parameters by combining advanced deep learning algorithms (i.e., Long Short-Term Memory (LSTM) and Informer) with causal inference, time-frequency analysis, and uncertainty quantification. The framework was demonstrated for total nitrogen (TN) forecasting in the largest artificial lakes in Asia (i.e., the Danjiangkou Reservoir, China) with six-year monitoring data from January 2017 to June 2022. The results showed that the pre-processing techniques based on causal inference and wavelet decomposition can significantly improve the performance of deep learning algorithms. Compared to the individual LSTM and Informer models, wavelet-coupled approaches diminished well the apparent forecasting errors of TN concentrations, with 24.39%, 32.68%, and 41.26% reduction at most in the average, standard deviation, and maximum values of the errors, respectively. In addition, a post-processing algorithm based on the Copula function and Bayesian theory was designed to quantify the uncertainty of predictions. With the help of this algorithm, each deterministic prediction of our model can correspond to a range of possible outputs. The 95% forecast confidence interval covered almost all the observations, which proves a measure of the reliability and robustness of the predictions. This study provides rich scientific references for applying advanced data-driven methods in time-series forecasting tasks and a practical methodological framework for water resources management and similar projects.
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  • 文章类型: Journal Article
    为了评估龙羊峡水库建设对黄河上游径流与泥沙负荷关系(RRSL)的影响,利用径流和泥沙负荷监测数据,通过滑动相关系数法识别变化点。然后用Copula函数,提出了径流和泥沙负荷变化前后的各种对抗情况,以创新性地揭示它们的变化关系。结果表明:(1)水库建设对黄河上游RRSL的影响很大,发生点在1987年。径流和泥沙负荷的相关性在变化前表现得更好,但在变化后趋于下降。(2)在变化之前或之后,径流遵循广义极值分布,而变化前的泥沙负荷服从正态分布,而是变化后的对数正态分布。同时,FrankCopula函数准确地模拟了变化前的RRSL,而ClaytonCopula函数是在变异后选择的。(3)径流和输沙负荷在变化前同步富贫的概率较高。变异后,RRSL显著降低;它们的同步概率降低了45.67%。同时,他们极端事件的异步概率明显增加。变异前的关节复发和共同复发间隔小于变异后的关节复发和共同复发间隔,随着它们的体积峰值的减小。这项研究为水库建设影响的径流和泥沙负荷提供了新的知识,并为水库的防洪和排沙方案提供指导。
    In order to evaluate the impact of the Longyangxia Reservoir construction on the relationship between runoff and sediment load (RRSL) in the upper reaches of the Yellow River, the runoff and sediment load monitoring data are used to identify variation point by sliding correlation coefficient method. Then with Copula function, the various countering situations of runoff and sediment load before and after variation are proposed to innovatively reveal their changing relations. The results demonstrate that (1) the reservoir construction exerts a great impact on the RRSL in the upper reaches of the Yellow River with the occurring variation point in 1987. The correlation of runoff and sediment load is presented better before variation but tends to worse decrease after variation. (2) Either before or after variation, runoff follows the generalized extreme value distribution, while sediment load before variation obeys the normal distribution, but the lognormal distribution after variation. Meanwhile, Frank Copula function accurately simulates the RRSL before variation, whereas Clayton Copula function is selected after variation. (3) The probability of synchronous rich and poor runoff and sediment load is higher before variation. After variation, the RRSL decreases significantly; their synchronous probability decreases by 45.67%. Meanwhile, the asynchronous probability of their extreme events evidently increases. The joint recurrence and co-recurrence intervals before variation are smaller than those after variation, along with the decreasing of their volume peak. This study provides new knowledge of runoff and sediment load influenced by reservoir construction, and also offers guidance for flood control and sediment load-discharge schemes of reservoir.
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  • 文章类型: Journal Article
    干旱在中国普遍存在,给经济和社会带来了相当大的损失。干旱错综复杂,具有多属性的随机过程(例如,持续时间,严重程度,强度,和返回期)。然而,大多数干旱评估倾向于关注单变量干旱特征,由于干旱属性之间存在相关性,因此不足以描述干旱的内在特征。在这项研究中,我们采用标准化降水指数,利用中国1961年至2020年的月度降水数据集识别干旱事件。然后使用单变量和基于copula的双变量方法来检查3-的干旱持续时间和严重程度,6-,和12个月的时间尺度。最后,我们使用层次聚类方法来识别中国大陆在不同重现期的干旱易发地区。结果表明,时间尺度在干旱行为的空间异质性中起着至关重要的作用。如平均特征,联合概率,和风险区域化。主要研究结果如下:(1)3个月和6个月时间尺度具有可比性的区域干旱特征,但不是12个月的时间尺度;(2)干旱严重程度越高,干旱持续时间越长;(3)新疆北部干旱风险越高,青海西部,西藏南部,中国西南,和长江中下游,在中国东南沿海地区较低,长白山,和大兴安岭;(4)根据干旱持续时间和严重程度的联合概率,中国大陆分为六个分区。我们的研究有望有助于更好地评估中国大陆的干旱风险。
    Droughts are widespread in China and have brought considerable losses to the economy and society. Droughts are intricate, stochastic processes with multi-attributes (e.g., duration, severity, intensity, and return period). However, most drought assessments tend to focus on univariate drought characteristics, which are inadequate to describe the intrinsic characteristics of droughts due to the existence of correlations between drought attributes. In this study, we employed the standardized precipitation index to identify drought events using China\'s monthly gridded precipitation dataset from 1961 to 2020. Univariate and copula-based bivariate methods were then used to examine drought duration and severity on 3-, 6-, and 12-month time scales. Finally, we used the hierarchical cluster method to identify drought-prone regions in mainland China at various return periods. Results revealed that time scale played an essential role in the spatial heterogeneity of drought behaviors, such as average characteristics, joint probability, and risk regionalization. The main findings were as follows: (1) 3- and 6-month time scales yielded comparable regional drought features, but not 12-month time scales; (2) higher drought severity was associated with longer drought duration; (3) drought risk was higher in the northern Xinjiang, western Qinghai, southern Tibet, southwest China, and the middle and lower reaches of the Yangtze River, and lower in the southeastern coastal areas of China, the Changbai Mountains, and the Greater Khingan Mountains; (4) mainland China was divided into six subregions according to joint probabilities of drought duration and severity. Our study is expected to contribute to better drought risk assessment in mainland China.
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  • 文章类型: Journal Article
    为偏高岭土作为富铝火山灰材料的工程应用提供理论依据,在高温蒸汽和标准养护条件下,探讨了偏高岭土对复合水泥基复合材料宏观和微观力学性能的促进作用。分析技术,其中涉及热重和纳米压痕,以及扫描电子显微镜-能量色散X射线光谱,被使用。为了分析实验数据,使用ACI经验公式和copula函数。MK-水泥胶结体系的水化程度之间的相关性,C-(A)-S-H相的Al/Si,研究了C-(A)-S-H凝胶相的纳米力学性能。根据先前的研究,MK-水泥复合胶凝体系在高温养护条件下的宏观力学性能和取代率可以在短期内得到提高,其中偏高岭土的最佳取代率为20%。ACI经验公式用于证明偏高岭土替代率之间的函数关系,固化时间,和抗压强度。MK-水泥胶结系统可以消除缺陷相,降低CH相含量,然后增加C-(A)-S-H凝胶相含量和堆积密度。C-(A)-S-H凝胶相的微观机械性能由于其相含量和Al/Si比而提高。此外,copula函数验证了C-(A)-S-H凝胶和Al/Si的纳米力学性能的依赖性。
    To provide the theoretical basis for the engineering application of metakaolin as aluminum-rich pozzolanic ash materials, the promoting effect of metakaolin on the macro- and micro-mechanical properties of composite cement-based composite materials was explored under high-temperature steam and standard curing conditions. Analysis techniques, which involved thermogravimetric and nanoindentation coupled with scanning electron microscopy-energy dispersive X-ray spectroscopy, were used. To analyze the experimental data, the ACI empirical formula and the copula function were used. The correlation among the hydration degree of the MK-cement cementation system, the Al/Si of the C-(A)-S-H phase, and the nanomechanical properties of the C-(A)-S-H gel phase was investigated. According to prior research, the macroscopic mechanical properties and the substitution rate of the MK-cement composite cementitious system can be improved under high-temperature curing conditions in a short period, in which the optimum substitution rate of metakaolin is 20%. The ACI empirical formula was used to demonstrate the functional relationship between the metakaolin replacement rate, curing time, and compressive strength. The MK-cement cementation system can eliminate the defect phase, reduce the CH phase content, and then increase the C-(A)-S-H gel phase content and bulk density. The micro-mechanical properties of the C-(A)-S-H gel phase rises due to its phase content and Al/Si ratio. Furthermore, the copula function verifies the dependence of the nanomechanical properties of C-(A)-S-H gel and Al/Si.
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