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星系的近似等光度概率和光度图的线性统计分析 被引量:1
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作者 黄洵 《天文与天体物理》 2018年第2期29-46,共18页
星系的光度在Z >0.0041全电磁波段普适光滑函数,在Z-logL图中存在近似等光度,近似等光度分析验证了当星系的光度是定值时,计算定值光度与距离(或与红移)无关;当某定值光度超过一定距离时无法观测到,在均匀宇宙极弱引力效应下,是暗物... 星系的光度在Z >0.0041全电磁波段普适光滑函数,在Z-logL图中存在近似等光度,近似等光度分析验证了当星系的光度是定值时,计算定值光度与距离(或与红移)无关;当某定值光度超过一定距离时无法观测到,在均匀宇宙极弱引力效应下,是暗物质存在条件之一。统计分析验证下可知,只凭logLλ1-logLλ2图不能了解点集紧致或疏散于对角线上,线性统计数字直观地了解logLλ1-logLλ2图的点集紧致或疏散于对角线上的特性。星系的电磁波在宇宙中长距离传播中受极弱引力效应,波长缩短exp(Z/2)倍,光度必须增加exp(Z/2)倍,比前述2种数据分析验证,星系的近似等光度和logLλ1-logLλ2线性关系分析更精确。补充了星系集群主要以星系长城局域的例子。 展开更多
关键词 红移光度图 L-L图线性统计 等光度样品统计方差 新引力宇宙度规 星系长城局域
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运用EXCEL处理煤田地质勘探中的煤心样品信息
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作者 仲劼 《科技传播》 2014年第12期248-248,240,共2页
在煤田地质报告编写的过程当中,常有大量样品进行统计分析。灵活运用Excel软件处理大量数据,尤其是VBA程序的合理使用对繁杂重复的工作往往可达到事半功倍的效果。本文就如何高效准确地完成该项工作进得一些探讨。
关键词 EXCEL 煤田地质勘探 样品统计 VBA
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Characterization and separation of pyrite from Abu Tartur black shale 被引量:6
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作者 Ibrahim S.S. El Kammar A.M. Guda A.M. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期565-571,共7页
This work aimed for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled i... This work aimed for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled in Abu Tartur plateau representing the pyrite-rich black shale of the U. Cretaceous age, Sample characterization was carried out using petrographic microscope, XRD, DTA/DTG, C/S and XRF techniques. Clay minerals, silt-sized quartz, calcite, and hematite were the main minerals associating pyr- ite (5.34g). Liberation behavior of the sample was about 80% below 5 μm. Sample processing was achieved through one-day soaking followed by classification using I inch Mozley hydro-cyclone where about 35.5% by weight went to underflow and 64.5% went to overflow. The underflow product was subjected to an advanced gravity separation process using SB-40 Falcon Concentrator through a CCD statistical design prepared by Design-Expert 6.0 software proposed to opti- mize the separation process through a study for the effects of frequency (Hz) and water pressure (Psi) on both assay and recovery of the sulfur-rich heavy fraction. A heavy concentrate weighed 10.90% with inorganic sulfur content reached 11.37% (21.24% pyrite) with overall recovery (50.01%) was obtained after two cleaning at the optimum conditions. 展开更多
关键词 Abu Tartur plateau Black shale PYRITE Falcon Concentrator
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Spatial Prediction of Soil Aggregate Stability and Aggregate-Associated Organic Carbon Content at the Catchment Scale Using Geostatistical Techniques 被引量:13
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作者 J.MOHAMMADI M.H.MOTAGHIAN 《Pedosphere》 SCIE CAS CSCD 2011年第3期389-399,共11页
The association of organic carbon with secondary particles (aggregates) results in its storage and retention in soil. A study was carried out at a catchment covering about 92 km2 to predict spatial variability of so... The association of organic carbon with secondary particles (aggregates) results in its storage and retention in soil. A study was carried out at a catchment covering about 92 km2 to predict spatial variability of soil water-stable aggregates (WSA), mean weight diameter (MWD) of aggregates and organic carbon (OC) content in macro.- (〉 2 mm), meso- (1-2 mm), and micro-aggregate (〈 1 mm) fractions, using geostatistical methods. One hundred and eleven soil samples were eSlleeted at the 0 10cm depth and fractionated into macro-, meso-, and mlcro-aggregates by wet sieving. The OC content was determined for each fraction. A greater percentage of water-stable aggregates was found for micro-aggregates, followed by meso-aggregates. Aggregate OC content was greatest in meso-aggregates (9 g kg-1), followed by micro-aggregates (7 g kg-1), while the least OC content was found in macro-aggregates (3 g kg-1). Although a significant effect (P = 0.000) of aggregate size on aggregate OC content was found, however, our findings did not support the model of aggregate hierarchy. Land use had a significant effect (P = 0.073) on aggregate OC content. The coefficients of variation (CVs) for OC contents associated with each aggregate fraction indicated macro-aggregates as the most variable (CV = 71%). Among the aggregate fractions, the micro-aggregate fraction had a lower CV value of 27%. macro-aggregates to 84% for micro-aggregates. Geostatistical analysis differences in their spatial patterns in both magnitude and space at variance for most aggregate-associated properties was lower than 45%. The mean content of WSA ranged from 15% for showed that the measured soil variables exhibited each aggregate size fraction. The relative nugget The range value for the variogram of water-stable aggregates was almost similar (about 3 km) for the three studied aggregate size classes. The range value for the variogram of aggregate-associated OC contents ranged from about 3 km for macro-aggregates to about 6.5 km for meso-aggregates. Kriged maps of predicted WSA, OC and MWD for the three studied aggregate size fractions showed clear spatial patterns. However, a close spatial similarity (co-regionalization) was observed between WSA and MWD. 展开更多
关键词 KRIGING organic matter VARIOGRAM water-stable aggregates
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Balanced augmented jackknife empirical likelihood for two sample U-statistics
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作者 Conghua Cheng Yiming Liu +1 位作者 Zhi Liu Wang Zhou 《Science China Mathematics》 SCIE CSCD 2018年第6期1129-1138,共10页
In this paper, we investigate the two sample U-statistics by jackknife empirical likelihood(JEL),a versatile nonparametric approach. More precisely, we propose the method of balanced augmented jackknife empirical like... In this paper, we investigate the two sample U-statistics by jackknife empirical likelihood(JEL),a versatile nonparametric approach. More precisely, we propose the method of balanced augmented jackknife empirical likelihood(BAJEL) by adding two artificial points to the original pseudo-value dataset, and we prove that the log likelihood ratio based on the expanded dataset tends to the χ~2 distribution. 展开更多
关键词 jackknife empirical likelihood U-STATISTICS ROC curves balanced augmented empirical likelihood
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Principle of nonlinear chemical fingerprint by using dissipative components in samples as well as calculation and evaluation of similarity 被引量:13
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作者 ZHANG TaiMing ZHAO Zhe +5 位作者 FANG XuanQi QIAO JunXi XIANG FengQin ZHU Rong LIANG YiZeng DING Feng 《Science China Chemistry》 SCIE EI CAS 2012年第2期304-322,共19页
Under the conditions of constant temperature and pressure,different influences of samples with different chemical components on the mechanism of nonlinear chemical reaction will cause different changes of the potentia... Under the conditions of constant temperature and pressure,different influences of samples with different chemical components on the mechanism of nonlinear chemical reaction will cause different changes of the potential-time relationship curve of the nonlinear chemical reaction system.Using it as the character,and using the B-Z nonlinear chemical system to use acetone and substrates in samples as main dissipative substances qua an example,the principle of nonlinear chemical fingerprint has been researched and discussed in detail.At the same time,the general method for calculating the system similarity about nonlinear chemical fingerprint was also put forward,and similarities of nonlinear chemistry fingerprints of different batches of Guhan Yangshengjing and 18 sorts of other samples were calculated by Euclidean distance,correlation coefficient,included angle cosine and system similarity,at the same time,the various similarities were analyzed.The results showed that,both of correlation coefficient and included angle cosine are unable to be used as the criterion for quantitatively evaluating the similarity of nonlinear chemistry fingerprint;as non-parametric similarity,Euclidean distance can accurately reflect the feature differences in the fingerprints,but as parametric similarity,sometimes,Euclidean distance can not accurately reflect the relative extent of characteristic difference in the nonlinear chemical fingerprints;system similarity can most truthfully reflect the characteristic difference in the nonlinear chemical fingerprints,and is the best evaluating method among the four ones.Therefore,system similarity can be used to quantitatively calculate the similar extent between the nonlinear chemical fingerprints.An economical,simple and convenient,easy pushing and effective method for identifying and evaluating complicated samples has successfully been put forward. 展开更多
关键词 dissipative components nonlinear chemical fingerprint principle system similarity identification EVALUATION sample
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