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Predicting Macroscopic Properties of Amorphous Monolayer Carbon via Pair Correlation Function
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作者 Mouyang Cheng Chenyan Wang +4 位作者 Chenxin Qin Yuxiang Zhang Qingyuan Zhang Han Li Ji Chen 《Chinese Physics Letters》 2025年第6期78-101,共24页
Establishing the structure-property relationship in amorphous materials has been a long-term grand challenge due to the lack of a unified description of the degree of disorder.In this work,we develop SPRamNet,a neural... Establishing the structure-property relationship in amorphous materials has been a long-term grand challenge due to the lack of a unified description of the degree of disorder.In this work,we develop SPRamNet,a neural network based machine-learning pipeline that effectively predicts structure-property relationship of amorphous material via global descriptors.Applying SPRamNet on the recently discovered amorphous monolayer carbon,we successfully predict the thermal and electronic properties.More importantly,we reveal that a short range of pair correlation function can readily encode sufficiently rich information of the structure of amorphous material.Utilizing powerful machine learning architectures,the encoded information can be decoded to reconstruct macroscopic properties involving many-body and long-range interactions.Establishing this hidden relationship offers a unified description of the degree of disorder and eliminates the heavy burden of measuring atomic structure,opening a new avenue in studying amorphous materials. 展开更多
关键词 neural network machine learning amorphous materials global descriptorsapplying amorphous monolayer carbonwe degree disorderin amorphous material pair correlation function
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A Two-Stage Feature Selection Method for Text Categorization by Using Category Correlation Degree and Latent Semantic Indexing 被引量:2
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作者 王飞 李彩虹 +2 位作者 王景山 徐娇 李廉 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第1期44-50,共7页
With the purpose of improving the accuracy of text categorization and reducing the dimension of the feature space,this paper proposes a two-stage feature selection method based on a novel category correlation degree(C... With the purpose of improving the accuracy of text categorization and reducing the dimension of the feature space,this paper proposes a two-stage feature selection method based on a novel category correlation degree(CCD)method and latent semantic indexing(LSI).In the first stage,a novel CCD method is proposed to select the most effective features for text classification,which is more effective than the traditional feature selection method.In the second stage,document representation requires a high dimensionality of the feature space and does not take into account the semantic relation between features,which leads to a poor categorization accuracy.So LSI method is proposed to solve these problems by using statistically derived conceptual indices to replace the individual terms which can discover the important correlative relationship between features and reduce the feature space dimension.Firstly,each feature in our algorithm is ranked depending on their importance of classification using CCD method.Secondly,we construct a new semantic space based on LSI method among features.The experimental results have proved that our method can reduce effectively the dimension of text vector and improve the performance of text categorization. 展开更多
关键词 text categorization feature selection latent semantic indexing(LSI) category correlation degree(CCD)
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Correlation Degree and Correlation Coefficient of Multi-Output Functions 被引量:1
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作者 JUGui-zhi ZHAOYa-qun 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期195-198,共4页
We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlati... We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlation degree and independency, the other is between the correlation degree and balance. Especially the paper discusses the correlation degree of affine multioutput functions. We demonstrate properties of the correlation coefficient of multi-output functions. One is the value range of the correlation coefficient, one is the relationship between the correlation coefficient and independency, and another is the sufficient and necessary condition that two multi-output functions are equivalent to each other. 展开更多
关键词 Key words multi output functions independency correlation degree BALANCE correlation coefficient
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The effects of degree correlations on network topologies and robustness 被引量:1
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作者 赵静 陶林 +3 位作者 俞鸿 骆建华 曹志伟 李亦学 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3571-3580,共10页
Complex networks have been applied to model numerous interactive nonlinear systems in the real world. Knowledge about network topology is crucial to an understanding of the function, performance and evolution of compl... Complex networks have been applied to model numerous interactive nonlinear systems in the real world. Knowledge about network topology is crucial to an understanding of the function, performance and evolution of complex systems. In the last few years, many network metrics and models have been proposed to investigate the network topology, dynamics and evolution. Since these network metrics and models are derived from a wide range of studies, a systematic study is required to investigate the correlations among them. The present paper explores the effect of degree correlation on the other network metrics through studying an ensemble of graphs where the degree sequence (set of degrees) is fixed. We show that to some extent, the characteristic path length, clustering coefficient, modular extent and robustness of networks are directly influenced by the degree correlation. 展开更多
关键词 network dynamics random graphs complex networks degree correlation
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Application of Grey Correlation Degree Analysis in Broad Bean Strain Screening 被引量:1
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作者 Lin ZENG Chunqin WU +6 位作者 Guotian YANG Chaozhong ZHANG Shunsheng LU Yunfei SONG Yan LIU Lamei YANG Guixian WU 《Agricultural Biotechnology》 CAS 2018年第3期49-52,54,共5页
[Objectives] The aim was to clarify the target and approach to purifying and selecting Baoshan Touxinlv broad bean. [Methods] In 2012,5 homozygous strains were selected successfully as the material,and completely rand... [Objectives] The aim was to clarify the target and approach to purifying and selecting Baoshan Touxinlv broad bean. [Methods] In 2012,5 homozygous strains were selected successfully as the material,and completely randomized block arrangement was adopted with 3 repeated trials to analyze the effects of plant height,effective length of podding branches,branch number per plant,pod number per plant,grain number per pod and 100-grain weight on the yield of each plant in the system. [Results] The results showed that the effects of the various factors on the yield of Baoshan broad beans were in the order of grain number per pod 〉 effective length of podding branches 〉 100-grain weight 〉 pod number per plant 〉 branch number per plant 〉 plant height. [Conclusions]In breeding new strains of Baoshan broad beans,under the premise of ensuring the seed nature and quality of the original variety,priority should be given to the gain number per pod and the increment of effective length of podding branches,followed by the pod number per plant,branch number per plant,plant height,which is the best way to breed new strains of Baoshan Touxinlv broad beans. 展开更多
关键词 Touxinlv broad bean strain Economic characters Grey correlation degree ANALYSIS Baoshan
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Three vertex degree correlations of fixed act-size collaboration networks
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作者 雷敏 赵清贵 侯振挺 《Journal of Central South University》 SCIE EI CAS 2011年第3期830-833,共4页
A rate equation approach was presented for the exact computation of the three vertex degree correlations of the fixed act-size collaboration networks.Measurements of the three vertex degree correlations were based on ... A rate equation approach was presented for the exact computation of the three vertex degree correlations of the fixed act-size collaboration networks.Measurements of the three vertex degree correlations were based on a rate equation in the continuous degree and time approximation for the average degree of the nearest neighbors of vertices of degree k,with an appropriate boundary condition.The rate equation proposed can be generalized in more sophisticated growing network models,and also extended to deal with related correlation measurements.Finally,in order to check the theoretical prediction,a numerical example was solved to demonstrate the performance of the degree correlation function. 展开更多
关键词 fixed act-size collaboration networks degree correlation function clustering coefficient Markov chain
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Effect of degree correlation on edge controllability of real networks
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作者 Shu-Lin Liu Shao-Peng Pang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期101-108,共8页
We use the controllability limit theory to study impact of correlation between in- and out-degrees (degree correlation) on edge controllability of real networks. Simulation results and analytic calculations show that ... We use the controllability limit theory to study impact of correlation between in- and out-degrees (degree correlation) on edge controllability of real networks. Simulation results and analytic calculations show that the degree correlation plays an important role in the edge controllability of real networks, especially dense real networks. The upper and lower controllability limits hold for all kinds of real networks. Any edge controllability in between the limits is achievable by properly adjusting the degree correlation. In addition, we find that the edge dynamics in some real networks with positive degree correlation may be difficult to control, and explain the rationality of this anomaly based on the controllability limit theory. 展开更多
关键词 complex network edge controllability degree correlation controllability limit
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An Analytical Approach for Degree Correlations in Complex Network
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作者 Kosuke Takagi 《World Journal of Mechanics》 2012年第3期171-174,共4页
We investigate correlations between neighbor degrees in the scale-free network. According to the empirical studies, it is known that the degree correlations exhibit nontrivial statistical behaviors. With using an anal... We investigate correlations between neighbor degrees in the scale-free network. According to the empirical studies, it is known that the degree correlations exhibit nontrivial statistical behaviors. With using an analytical approach, we show that the scale-freeness and one of statistical laws for degree correlations can be reproduced consistently in a unified framework. Our result would have its importance in understanding the mechanisms which generate the complex network. 展开更多
关键词 SCALE-FREE Network degree DISTRIBUTION degree correlationS POWER LAW
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Correlation analysis of climate comfort degree of tourism and annual variation of tourist flow in Tai’an, Shandong province
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作者 WANG Meng-wen LI Tong +1 位作者 QI Wei WANG Peng-tao 《Ecological Economy》 2019年第3期180-185,共6页
The tourism climate comfort degree can directly affect the trip of tourists,and can determine the length of the tourist season and the development of the tourist projects.In order to explore the relationship between t... The tourism climate comfort degree can directly affect the trip of tourists,and can determine the length of the tourist season and the development of the tourist projects.In order to explore the relationship between the climate comfort degree and the annual variation of tourist flow combined with 1981-2010 climate related data,this paper analyzes the comfort degree of tourism climate in Tai’an,the annual change divide tourist season into high season,shoulder season and off-season.With regression analysis,the correlation between tourism climate comfort degree and annual variation of passenger flow is analyzed.The final result is as follows:As for Tai’an,in May and September the rank of humiditytemperature index(THI)is A,with the most pleasant climate,the most suitable for tourism activities.In April,August and October the rank of THI is B or b,represented as suitable climate,suitable for tourism activities.In June and July,the climate is hot,with a low tourism suitability grade,In February,March and November,the climate is cold,with a poor tourism suitability grade.In January and December the climate is frigid,not suitable for tourism activities.The final conclusion is below:the tourist traffic variation within the year is mainly affected by climate comfort effect.The elastic coefficient is 0.927%.In addition,the tourist traffic variation within the year is also affected by the summer vacation,the Golden Week and the impact of preferential policies.All the above provide a scientific basis for the prediction of Tai’an’s tourist flow in a year,the development of tourism and tourist scenic management. 展开更多
关键词 CLIMATE COMFORT degree TOURIST flow correlation analysis Tai’an
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Application of grey weighted related degree to the ambient air quality assessment 被引量:3
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作者 孟宪林 沈晋 +1 位作者 孙丽欣 吕晓莹 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第4期395-397,共3页
It is difficult to establish the integrated method to assess the ambient air quality because the atmospheric environmental system is composed of several environmental elements, which contains many contanination factor... It is difficult to establish the integrated method to assess the ambient air quality because the atmospheric environmental system is composed of several environmental elements, which contains many contanination factors. In view of the typical grey system character of the monitored data in the ambient air, this paper introduces the weighted value to obtain related degree during applying the method of grey related degree analvsis to assess ambient air quality by each polluting factor producing different effects on the environment quality. This method could give more reasonable and reliable evaluating results. Taking the monitored data of Harbin, a provincial city of Heilongjiang, for example in this paper, the result of assessment by this method was coincide,It with the actual environmental quality of Harbin. 展开更多
关键词 grey correlated degree environmental assessment weighting
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The Changes of Fiscal Agriculture-Supporting Expenditure and Farmers' Income Based on Grey Correlation Theory 被引量:2
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作者 LIU Yao-sen School of Economics and Management,Chongqing Three Gorges University,Chongqing 404100,China 《Asian Agricultural Research》 2011年第3期92-95,共4页
According to the relevant data of China Statistical Yearbook and Chinese Rural Statistical Yearbook in the year of 2009,the changes of grey correlation degree of farmers' net income,various items of incomes,nation... According to the relevant data of China Statistical Yearbook and Chinese Rural Statistical Yearbook in the year of 2009,the changes of grey correlation degree of farmers' net income,various items of incomes,national gross agriculture-supporting expenditure and various items of expenditures,farmers' net income and various items of fiscal agriculture-supporting expenditure in the Eighth Five-Year Plan,Ninth Five-Year Plan and Tenth Five-Year Plan by using grey correlation degree and the by choosing seven indicators covering income from wage and salary,income from household business,transfer income and property income,agricultural production-supporting expenditure,agricultural basic construction expenditure,expenses of three items of agricultural technology and the fee of rural relief.The results show that the grey correlation degree of each time period and household net income shows the downward trend;from overall perspective,the grey correlation degree of national gross agriculture-supporting expenditure,agricultural basic construction expenditure and agricultural production-supporting expenditure shows the descending trend;the grey correlation degree of fiscal agricultural supporting expenditure and the expenditure of three items of agricultural technology and fee of rural relief show the upward trend;the influence of agricultural production-supporting expenditure on farmers' income shows downward trend;the influence of agricultural basic construction on farmers' income shows upward trend;the fee of rural relief play an active role in the promoting the farmers' income increase;the role played by fee of rural relief in promoting farmers' income increase should be further increased;the increase of farmers' income shows great reliance on agricultural science and technology.In the end,the relevant suggestions on establishing stable increase mechanism of fiscal agricultural support and insisting on the dynamic adjustment of the structure of fiscal agricultural supporting capital are put forward. 展开更多
关键词 FISCAL agricultural-supporting EXPENDITURE FARMERS
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Characterization of the pairwise correlations in different quantum networks consisting of four-wave mixers and beamsplitters
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作者 祁健 忻俊 +1 位作者 王海龙 荆杰泰 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期153-160,共8页
We investigate the performances of the pairwise correlations(PCs) in different quantum networks consisting of fourwave mixers(FWMs) and beamsplitters(BSs). PCs with quantum correlation in different quantum netwo... We investigate the performances of the pairwise correlations(PCs) in different quantum networks consisting of fourwave mixers(FWMs) and beamsplitters(BSs). PCs with quantum correlation in different quantum networks can be verified by calculating the degree of relative intensity squeezing for any pair of all the output fields. More interestingly, the quantum correlation recovery and enhancement are present in the FWM+BS network and the repulsion effect phenomena(signal(idler)-frequency mode cannot be quantum correlated with the other two idler(signal)-frequency modes simultaneously)between the PCs with quantum correlation are predicted in the FWM + FWM and FWM + FWM + FWM networks. Our results presented here pave the way for the manipulation of the quantum correlation in quantum networks. 展开更多
关键词 pairwise correlation four-wave mixer degree of relative intensity squeezing quantum network
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Determining the degree of saturation of rocks as a function of time:A case study from mountainous area of Turkey
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作者 Serhat DAG 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2307-2319,共13页
The aim of this study is to scrutinize whether, in terms of saturation, the 48 hour duration suggested by ISRM(International Society for Rock Mechanics) methods and ASTM(American Society for Testing and Materials) sta... The aim of this study is to scrutinize whether, in terms of saturation, the 48 hour duration suggested by ISRM(International Society for Rock Mechanics) methods and ASTM(American Society for Testing and Materials) standard in rocks is sufficient or not, and to examine how the degree of saturation of rocks may be determined as a function of time. For this purpose, samples from five different rock groups including igneous(andesite, granite, andesitic tuff) and sedimentary(limestone, sandstone) exposed in Gümü?hane city which is from mountainous area of north-eastern Turkey, have been compiled. Measurements were taken on the samples left for saturation under laboratory conditions as a result of which the degree of saturation values at the end of these time periods were determined. Similarly, at the end of 48 hours, the samples were left to dry under atmospheric conditions in the laboratory environment and their time dependent degree of saturation were also calculated at different times. The changes as a function of time in the degree of saturation were then examined mathematically using non-linear, exponential and logarithmic functions. Graphs and equations related with the acquired time-degree of saturation values and the correlation coefficient(r) values for these equalities have indicated a high accordance between time and degree of saturation for the studied rock groups. The applied methodology will be beneficial for determining the degree of saturation based on time for engineering studies that will be carried out in similar lithologies. 展开更多
关键词 degree of saturation POROSITY TIME correlation coefficient
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Analysis on the Change Characteristics of the Correlation between Land Use Structure and Energy Consumption and Carbon Emissions in Kunming from 1997 to 2017
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作者 Li Zhang Ping Wang 《Journal of Geoscience and Environment Protection》 2021年第6期155-166,共12页
This study takes Kunming City, Yunnan Province, China as the research area, to provide reference basis for revealing the change law of land use structure and energy consumption and carbon emissions in Kunming, optimiz... This study takes Kunming City, Yunnan Province, China as the research area, to provide reference basis for revealing the change law of land use structure and energy consumption and carbon emissions in Kunming, optimizing land use structure and realizing the development of low-carbon city. Based on the data of land use structure and energy consumption in Kunming from 1997 to 2017, based on the estimation of total energy consumption carbon emissions, carbon intensity and per capita carbon emissions, the correlation between land use structure and energy consumption carbon emissions in Kunming has been calculated and analyzed in the past 20 years. Results: 1) The total amount of carbon emissions in Kunming has increased significantly in the past 20 years. It increased from 34.46 × 10</span><sup><span style="font-family:Verdana;">5</span></sup><span style="font-family:Verdana;"> t to 95.09 × 10</span><sup><span style="font-family:Verdana;">5</span></sup><span style="font-family:Verdana;"> t, an increase of about 2.8 times. 2) The types of land use with the highest correlation between land use structure and total carbon emissions of energy consumption, carbon emission intensity and per capita carbon emissions are urban and village and industrial and mining land (0.8258), cultivated land (0.8733) and garden land (0.7971) respectively. 3) The correlation between construction land and total carbon emissions is greater than that of agricultural land. Conclusion: There is a close correlation between land use structure and carbon emissions from energy consumption in Kunming. 展开更多
关键词 Kunming City Land Use Structure Energy Consumption Carbon Emissions correlation degree
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A Correlation Analysis of Tourism Based on Gray Theory——A case of Xingwen County
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作者 WEI Ya-li 1,HUI Wei 2,WANG Li-guo 3(1 College of Resources and Environment,Sichuan Agricultural University,Yaan,Sichuan 625014,2Agronomy College,Sichuan Agricultural University,Yaan,Sichuan 625014,3college of land environment science,Jiangxi Agricultural University,Nanchang,Jiangxi 330045) 《四川地质学报》 2009年第S1期133-139,共7页
Tourism industry has already become an important part of national economy,which not only played a positive role in the development of the economy,but promoted the adjustment and optimization of industrial structure.Th... Tourism industry has already become an important part of national economy,which not only played a positive role in the development of the economy,but promoted the adjustment and optimization of industrial structure.The paper analyzes the correlation between the tourism industry and the other industry through changes of the Xingwen County tourism industrial output value in the past seven years.With the Gray Model,the correlation degree among the tourism industry and agriculture,industry,transport,wholesale and retail trade,postal and telecommunications industries is measured.The analysis result indicates that the order of the corresponding correlation degree:catering accommodation is 0.691> wholesale and retail is 0.617 > agriculture is 0.616 > Postal and telecommunications industry is 0.610> Transport is 0.602> Industry is 0.537.In accordance with the actual conditions of the industry in Xingwen,the industrial development policies and measures are put forward,which help the tourism industry Xingwen their rapid,coordinated and highly efficient operation. 展开更多
关键词 TOURISM industry ENTERPRISE Relationship GRAY RELATIONAL model correlation degree.
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利用灰色关联度分析法评价新疆水稻农艺性状、品质与产量间的关系 被引量:2
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作者 赵志强 朱凌云 +6 位作者 唐福森 康民泰 袁杰 张燕红 王奉斌 杜孝敬 侯天钰 《山东农业大学学报(自然科学版)》 北大核心 2025年第1期167-173,共7页
为水稻品种选育中选择多个优良目标性状指明方向,高质高效完成目标性状选定,加速育种进程,本研究以新疆常用的24个水稻品种(系)为材料,利用灰色关联度分析方法研究了水稻主要农艺性状、外观品质、碾米品质、蒸煮品质及产量等15个性状指... 为水稻品种选育中选择多个优良目标性状指明方向,高质高效完成目标性状选定,加速育种进程,本研究以新疆常用的24个水稻品种(系)为材料,利用灰色关联度分析方法研究了水稻主要农艺性状、外观品质、碾米品质、蒸煮品质及产量等15个性状指标之间的相互关系。结果表明,与水稻产量关联度高的农艺性状为千粒重、株高和结实率;关联度高的2个外观品质是粒长和长/宽比;关联度高的2个碾米品质是出糙率和精米率;关联度高的1个蒸煮品质是直链淀粉含量。在研究水稻品质影响因素时应注重考虑粒长、出糙率和直链淀粉含量等性状指标,且应以水稻长/宽比、精米率、整精米率、胶稠度等性状作为参考指标。同时产量方面要侧重千粒重、株高和结实率的改良。研究结果可以为水稻育种工作提供科学依据。 展开更多
关键词 水稻产量 农艺性状 品质 灰色关联度
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原子吸收光谱法测定矿石中Au的分析技术及最优化模型研究 被引量:2
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作者 王鹏 门倩妮 +7 位作者 甘黎明 白金峰 王啸 井斌强 寇少磊 刘慧蓝 何涛 刘玖芬 《光谱学与光谱分析》 北大核心 2025年第2期426-433,共8页
矿石中Au通常以颗粒金或者晶格金的形式存在,在不同类型的金矿石中赋存状态不同,其特殊的延展性引起的颗粒效应对于Au样品的分析技术带来挑战,并且其制备流程要素繁多且不易控制,直接影响Au分析的准确性和稳定性。以矿石中金元素为研究... 矿石中Au通常以颗粒金或者晶格金的形式存在,在不同类型的金矿石中赋存状态不同,其特殊的延展性引起的颗粒效应对于Au样品的分析技术带来挑战,并且其制备流程要素繁多且不易控制,直接影响Au分析的准确性和稳定性。以矿石中金元素为研究对象,建立泡塑吸附-原子吸收光谱法测定矿石中Au的分析方法,针对样品测试流程中的关键要素进行定性判断和定量计算,提出基于灰色关联度-响应曲面法的最优化模型。讨论样品分析技术中焙烧、消解、富集和解脱等重要环节,确定焙烧方式、消解酸度、富集时间和硫脲浓度为优化要素,设计正交试验并进行相关性分析,计算灰色关联系数并进行极差确定,定性判断各优化要素的显著性。中心组合设计结合响应曲面法原理制作显著水平表,建立二次多项式回归方程的预测模型并进行显著性分析,绘制三维响应曲面图和二维等高线图对实验数据进行拟合分析,确定最优化模型参数焙烧方式、消解酸度、富集时间和硫脲浓度分别为阶梯式分段焙烧、10.58%、40.00 min、11.65 g·L^(-1)。实验结果表明,在最优化模型条件下对金矿石国家一级标准物质进行制备测试,其方法检出限为0.021,测定下限为0.077,加标回收率为91.6%~104.5%,其正确度和精密度均符合GB/T 20899.2—2019质量控制要求;同时对陕西西秦岭地区和甘肃梅川地区外检样品进行方法验证比对,其相对偏差不超过10%且评价结果均为优秀,表明该检测优化模型方法在实际样品中的应用依然准确可靠,具备正确性和科学性。该研究对于地质矿产实验室快速、准确、简便分析Au元素提出新方法,为检验检测领域中优化多目标参数组合的课题提供了新的思路,同时为新一轮战略找矿行动的准确测试贡献力量。 展开更多
关键词 原子吸收光谱法 灰色关联度 响应曲面法 中心组合设计 质量控制
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混合近邻和多簇合并的密度峰值聚类算法 被引量:1
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作者 吕莉 赵妞 +2 位作者 肖人彬 王新峰 韩龙哲 《控制与决策》 北大核心 2025年第7期2194-2202,共9页
密度峰值聚类算法简单、高效,可识别任意维度和形状类簇,已在各领域得到广泛应用.然而,密度峰值聚类算法也存在一些问题,如:对截断距离参数敏感、难以发现低密度区域的类簇中心以及容易产生“多米诺效应”.为此,提出混合近邻和多簇合并... 密度峰值聚类算法简单、高效,可识别任意维度和形状类簇,已在各领域得到广泛应用.然而,密度峰值聚类算法也存在一些问题,如:对截断距离参数敏感、难以发现低密度区域的类簇中心以及容易产生“多米诺效应”.为此,提出混合近邻和多簇合并的密度峰值聚类算法.首先,综合考虑样本的全局分布与局部结构,引入自然近邻与k近邻重新定义局部密度,消除对截断距离参数的敏感,并提高低密度区域样本的局部密度以增加类簇中心的识别度;其次,将样本划分为多个微簇,并利用簇间关联度进行合并,减少距离类簇中心较远的样本的分配错误,从而有效缓解分配错误连带效应.使用人工数据与真实数据进行测试,结果表明,所提出算法的综合性能优于对比算法. 展开更多
关键词 聚类 自然近邻 K近邻 簇间关联度 密度峰值 局部密度
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2009-2019年天津市肺结核发病季节性和空间分布特征分析 被引量:2
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作者 李晓蓉 庞学文 王春花 《热带医学杂志》 2025年第1期104-109,I0003,共7页
目的对2009-2019年天津市肺结核发病的季节性和空间分布特征进行分析,为制定有效的肺结核防控措施提供理论依据。方法通过中国疾病预防控制信息系统中的结核病管理信息系统收集天津市2009-2019年确诊登记的肺结核患者病案信息,从综合管... 目的对2009-2019年天津市肺结核发病的季节性和空间分布特征进行分析,为制定有效的肺结核防控措施提供理论依据。方法通过中国疾病预防控制信息系统中的结核病管理信息系统收集天津市2009-2019年确诊登记的肺结核患者病案信息,从综合管理系统中收集各区常住人口数。采用季节指数法和集中度法分析肺结核发病的季节性特征;采用改良圆形分布法计算肺结核发病的高峰日和发病高峰期;应用ArcGIS对天津市肺结核发病的空间分布特征进行分析。结果2009-2019年天津市肺结核平均发病率为23.93/10万,北辰区最高(31.27/10万),其次是河东区(30.43/10万)和红桥区(30.11/10万)。集中度法求得天津市2009-2019年肺结核发病的M值为0.040(0.009~0.100),表明季节性较差。上半年4月、下半年7月季节指数最高,2月和10月季节指数最低。改良圆形分布法求得上下半年发病高峰日分别为4月29日和7月27日,发病高峰期分别为2月21日-7月5日和5月10日-10月13日,经雷氏Z值检验,平均角峰值差异均有统计学意义(P<0.001)。三维趋势分析显示,发病率总体上东西方向呈明显的中间低两边高的“U”型,南北方向呈北高南低的弧形变化趋势;全局Moran's I指数为0.284,P值为0.021,提示整体存在正向空间自相关,呈聚集分布;局部空间自相关分析结果显示,天津市2009-2019年肺结核发病热点区域主要集中在河北区、北辰区、红桥区和河西区,冷点区为静海区。结论4月和7月是天津市肺结核发病的高峰期,发病热点区主要位于市内六区、东丽区和北辰区,是天津市肺结核防控的重点区域。 展开更多
关键词 结核 集中度 圆形分布法 季节特征 空间自相关分析
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