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光学显微镜在粒度定量统计测定中的应用
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作者 袁小燕 《江苏冶金》 1998年第6期50-51,共2页
对于200目以上(>0.075mm)的大颗粒进行粒度分布测定时,普通粒度仪难于用沉降法测定。笔者在显微镜下用显微计数法统计,取得较好效果,为大颗粒的粒度测定提供了一条有效可行的途径。
关键词 光学显微镜 统计测定 矿物 粒度
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广告效果的统计测定与分析 被引量:3
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作者 郝艳茹 《统计科学与实践(天津)》 2000年第5期31-33,共3页
关键词 广告效果 统计分析 统计测定
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临床检验定量测定统计质控方法选择和设计表格 被引量:3
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作者 王治国 王薇 +1 位作者 李小鹏 武平原 《检验医学》 CAS 北大核心 2004年第1期10-11,共2页
关键词 临床检验 定量测定统计 质控方法 选择 设计表格
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某院儿科住院患儿季节变动的统计学测定及趋势预测 被引量:1
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作者 孙政 《中国卫生统计》 CSCD 北大核心 2004年第3期190-191,共2页
关键词 儿科 住院患儿 季节变动 统计测定 趋势预测 直线方程
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饲养管理效果变化量的测定
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作者 杨运清 李淑玲 《甘肃畜牧兽医》 北大核心 1998年第2期38-39,共2页
饲养管理效果变化量的测定杨运清李淑玲(东北农业大学哈尔滨150030)(哈尔滨动物园)在筛选优化饲养管理条件或改进现行饲养管理条件过程中,经常遇到不同饲养管理效果差异或变化量的统计测定问题。而就两种饲养管理条件的比较... 饲养管理效果变化量的测定杨运清李淑玲(东北农业大学哈尔滨150030)(哈尔滨动物园)在筛选优化饲养管理条件或改进现行饲养管理条件过程中,经常遇到不同饲养管理效果差异或变化量的统计测定问题。而就两种饲养管理条件的比较来说,饲养管理效果差异或变化量分两... 展开更多
关键词 饲养管理 绝对变化量 相对变化量 统计测定
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转变经济增长方式的统计考察 被引量:3
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作者 王亚雄 《财经理论与实践》 1998年第4期26-28,共3页
关键词 经济增长方式 统计指标 统计评价 统计测定
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西藏甲玛矿区岩石物性统计及应用 被引量:4
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作者 屈挺 贺日政 +3 位作者 鱼鹏亮 王素芬 陈小龙 刘建利 《物探与化探》 CAS 北大核心 2021年第3期661-668,共8页
西藏甲玛矿区作为冈底斯东段斑岩型铜矿带内最重要的大型矿床之一,岩石种类众多,不同地层及侵入岩的物性特征复杂多样。以往岩石物性工作由于缺乏足够的重视,岩石测定的种类不够全面,对甲玛矿区的岩石物性特征缺乏系统性和完整性的认识... 西藏甲玛矿区作为冈底斯东段斑岩型铜矿带内最重要的大型矿床之一,岩石种类众多,不同地层及侵入岩的物性特征复杂多样。以往岩石物性工作由于缺乏足够的重视,岩石测定的种类不够全面,对甲玛矿区的岩石物性特征缺乏系统性和完整性的认识。本次在以往岩石物性资料分析的基础上,通过对甲玛矿区较为典型的6口钻孔岩心标本进行物性测定和统计分析,总结出矿区的岩石密度、磁性、电阻率和极化率特征,建立了矿区岩石—地质地球物理模型,为矿区后续开展地球物理工作提供可靠的依据。同时,利用本次岩石电性参数对矿区开展的大地电磁测深剖面上引起静态效应的测点进行了校正,为大地电磁测深剖面解释提供依据,并与钻孔资料进行了对比,取得了较好的勘探效果。 展开更多
关键词 甲玛矿区 岩石物性测定统计 岩石—地质地球物理模型 大地电磁
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低碳钢显微结构的EBSD表征 被引量:10
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作者 陈家光 曹圣泉 《物理测试》 CAS 2005年第2期1-5,11,共6页
近年来,新开发的电子背散射衍射技术将多晶材料的显微组织、微区成分与结晶学数据分析联系起来,能对晶界类型、取向、位向差和结构及其分布进行观察、统计测定和定量分析,从而建立了晶界结构、取向和织构等与多晶材料性能的定量和半定... 近年来,新开发的电子背散射衍射技术将多晶材料的显微组织、微区成分与结晶学数据分析联系起来,能对晶界类型、取向、位向差和结构及其分布进行观察、统计测定和定量分析,从而建立了晶界结构、取向和织构等与多晶材料性能的定量和半定量关系,成为现代材料研究的重要实验技术。笔者结合低碳钢生产中的一些实际问题,扼要介绍了电子背散射衍射技术中的晶体取向图在多晶材料显微结构表征中的应用。 展开更多
关键词 低碳钢 EBSD 电子背散射衍射技术 显微结构表征 多晶材料 显微组织 数据分析 微区成分 定量分析 统计测定 晶界结构 定量关系 材料性能 实验技术 材料研究 实际问题 晶体取向 结晶学 织构
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Features and correct application of coal vitrinite reflectance index 被引量:7
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作者 YAO Bo-yuan LI De-ping 《Journal of Coal Science & Engineering(China)》 2012年第4期400-406,共7页
The law of mathematical statistics, which the coal vitrinite reflectance index obeys, the existing vitrinite representing deviations, and the advantages of judging coalification and the shortage of judging coal type w... The law of mathematical statistics, which the coal vitrinite reflectance index obeys, the existing vitrinite representing deviations, and the advantages of judging coalification and the shortage of judging coal type were analyzed. The advantages and disadvantages of various determination methods and the expression index and different methods of identifying vitrinite on the determination results were compared. The vitality of coal vitrinite reflectance depends on its full play the unique function of reflectance histogram and the systematic errors between different determination methods do not affect the application based on reflectance histogram are considered. 展开更多
关键词 coal vitrinite reflectance determination methods INDEX reflectance histogram APPLICATION
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Development and Optimization of an Alternative Methodology for Detection of Milk Adulteration by Water 被引量:2
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作者 Wesley William Gongalves Nascimento Marcone Augusto Leal de Oliveira1 +3 位作者 Marcone Augusto Leal de Oliveira Marco Antonio Moreira Furtado Virgilio de Carvalho dos Anjos Maria Jose Valenzuela Bell 《Journal of Food Science and Engineering》 2013年第7期363-370,共8页
This paper presents a process which allows the determination of milk adulteration by water. Considering the limitations of the reference method (cryoscopy), the proposed methodology matches electrical conductivity a... This paper presents a process which allows the determination of milk adulteration by water. Considering the limitations of the reference method (cryoscopy), the proposed methodology matches electrical conductivity and cryoscopy index measurements. Based on statistical procedures, a linear descriptive model is achieved to quantify adulteration of milk with water. It is also shown that electrical conductivity measurements allow the detection of adulteration with water and sodium chloride. 展开更多
关键词 MILK electrical conductivity cryoscopy ADULTERATION water.
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A three-dimensional positioning method based on three satellites 被引量:2
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作者 滕云龙 师奕兵 《Journal of Central South University》 SCIE EI CAS 2012年第12期3449-3453,共5页
A three-dimensional positioning method for global positioning system(GPS)receivers based on three satellites was proposed.In the method,the measurement equation used for positioning calculation was expanded by means o... A three-dimensional positioning method for global positioning system(GPS)receivers based on three satellites was proposed.In the method,the measurement equation used for positioning calculation was expanded by means of two measures.In this case,the measurement equation could be solved,and the function of positioning calculation could be performed.The detailed steps of the method and how to evaluate the positioning precision of the method were given,respectively.The positioning performance of the method was demonstrated through some experiments.It is shown that the method can provide the three-dimensional positioning information under the condition that there are only three useful satellites. 展开更多
关键词 global positioning system three satellites positioning calculation positioning precision
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ROBUST OBSERVER DESIGN FOR A CLASS OF UNCERTAIN NONLINEAR LARGE SCALE SYSTEMS *
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作者 姜斌 王江 王先来 《Transactions of Tianjin University》 EI CAS 1996年第2期32+29-31,共4页
In this paper, a mathematic description of a class of uncertain nonlinear large scale systems based on some practical application is given. A designing method to construct observers for su... In this paper, a mathematic description of a class of uncertain nonlinear large scale systems based on some practical application is given. A designing method to construct observers for such kind of nonlinear composite systems is developed. The unknown parameters and disturbances are assumed to be neither linear nor matched. A numerical example is used to illustrate the efficiency of our results. 展开更多
关键词 nonlinear large scale systems uncertainty observer design
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A TREND DISPLACEMENT ANALYSIS FOR SPACE AND TIME ON XINTAN LANDSLIDE
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作者 贺可强 《Journal of Coal Science & Engineering(China)》 1998年第1期51-55,共5页
This paper, having made systematic trend analysis on the front and rear segments of Xintan landslide for space and time respectively by using matbematical statistical principles,discovered that there is obvious trend ... This paper, having made systematic trend analysis on the front and rear segments of Xintan landslide for space and time respectively by using matbematical statistical principles,discovered that there is obvious trend displacement Of the monitoring points in the rear margin area of the slope and the rates of trend displacement gradually increase with time whereas there is no trend displacement of the monitoring points in the front margin area. This result suggests that the rear margin area of segment is an area of overall sliding and is transforming towards destabilization whereas the front margin area is an area of relative stability. This analytical result well coincides with the conclusion of evaluation on dynamic stability. The analytical result mentioned above shows that the medium to short term forecast and prediction of slope stability can be made by using trend displacement analysis technique in order to achieve the goal of timely evaluation and prevention. 展开更多
关键词 trend displacement space and time LANDSLIDE mathematical statistical principle
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Production of a Mathematic Equation Using Statistical Data for the Determination of Kinematic Viscosity in Blends of Diesel Fuel with Biodiesel
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作者 Constantinos G. Tsanaktsidis Konstantinos G. Spinthiropoulos +2 位作者 Stavros G. Christidis Vasileios M. Basileiadis Alexandros E. Garefalakis 《Computer Technology and Application》 2012年第5期393-399,共7页
In this paper, the authors try to export an equation which describes the variation of kinematic viscosity in blends of diesel fuel with biodiesel. Using specific volume of these blends, the authors determine kinematic... In this paper, the authors try to export an equation which describes the variation of kinematic viscosity in blends of diesel fuel with biodiesel. Using specific volume of these blends, the authors determine kinematic viscosity via method ASTM D 445-06 using a capillary glass viscometer in order to study the contribution of quantity of biodiesel and convert the statistical data into mathematic relation as a specific formula, attempting to achieve an empirical evaluation. Trying to accomplish this, the authors studied the way how the values of variables are changed and whether a relation exists using dispersion diagrams. From the graphic depiction, the authors realized that the relation is linear and they proceeded to regression analysis. The analysis extracted the conclusion that the relation was strong and the values of the dependent variable kinematic viscosity was depended on a large percentage of the values of the mixture of fuels. 展开更多
关键词 DIESEL BIODIESEL statistical analysis kinematic viscosity equation.
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Evaluation of photon beam dose calculation accuracy of treatment planning systems using in vivo dosimetry
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作者 Mohamed Ibrahim Wahib M.Attia Khaled M.Elshahat 《Oncology and Translational Medicine》 2016年第5期234-238,共5页
Objective The treatment planning system currently represents one of the basics of radiation therapy,because it is the only method to estimate patient dose delivery fast forward and accurately represent estimated tumor... Objective The treatment planning system currently represents one of the basics of radiation therapy,because it is the only method to estimate patient dose delivery fast forward and accurately represent estimated tumor location of the tumor with the possibility of estimating densities in the tissue surrounding the tumor to overcome dose calculation defects but radial estimated the patient.Despite the flaws associated with the systems and calculates the dose of your programs in all programs currently existing in the world.Than necessary,to the existence of a review of the accuracy of accounts and how to confirm the radiation dose to the patient programs.Methods A total of 35 cancer patients were considered for this study,with 245 field measurements made with low-and high-energy diode detectors for brain and prostate cases.The treatments for all patients were planned using Eclipse Treatment Planning System version 13.6.Results Of the 105 field measurements made for the prostate cancer patients,16 included discrepancies outside the ±5% action level.Of the 145 measurements taken of the brain cases,there were four outside the ±5% action level.The results indicated a higher degree of accuracy.The study revealed that,for the prostate measurements,the higher discrepancy in the doses for the particular fields(exceeding the action level) may have been due to the isocenter being very close to the jaws and multi-leaf collimator of the linear accelerator machine.As a result,scatter from the jaws and the multi-leaf collimator could have contributed to the high dose delivered to the diode;hence,a probable higher discrepancy of the dose in more brain cases due highest quality of VMAT technique and fixation system.Conclusion A greater percentage of the observed discrepancies were well within the set tolerance level.However,it is recommended that the positioning of the diode on the patient's skin and the angular sensitivity of the diodes be reconsidered.It is also recommended that a more accurate calculation of expected diode values be performed,especially for fields that pass through the table.These efforts would achieve action levels of ±5%. 展开更多
关键词 DIODES in vivo dosimetry RADIOTHERAPY dose verification
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Analysis the First Arrival of P-Wave of Ina-TEWS and CTBT Stations to Support Earthquake Early Warning
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作者 Hendar Gunawan Nanang T. Puspito +1 位作者 Gunawan Ibrahim Prih. Harjadi 《Journal of Civil Engineering and Architecture》 2013年第6期746-755,共10页
The authors make the analysis of first arrivals of the P-wave from Ina-TEWS (Indonesian tsunami early warning system) and CTBT (comprehensive nuclear-test-band treaty) stations. These are used for earthquake early... The authors make the analysis of first arrivals of the P-wave from Ina-TEWS (Indonesian tsunami early warning system) and CTBT (comprehensive nuclear-test-band treaty) stations. These are used for earthquake early warning, magnitude determination and potential earthquake hazard mitigation based on seismogram acceleration. This research is focused on the study of energy duration of high frequency, and the maximum displacement of P-waves by observing broadband seismograms. The further analysis consists of deconvolution, integration or defferentiation, recursive filtering for data restitution, and applying a Butterworth filter of second order. The Butterworth filter uses high frequency 0.075 Hz to cut the effect of drift, and band-pass frequency 2-4 Hz for use in magnitude calculation. The authors choose potentially damaging earthquakes to be greater than Mw 〉 6.0. Based on the trigger on the three seconds the first arrival P-wave, the dominant period (Td) and amplitude displacement (Pd) was calculated by using data CISI (Indonesian CI Sompet) seismological station, Garut (west Java) and tested for data CTBT, LEM bang, Bandung (LEM station). This research resulted determination of the P-wave arrival time accurately using integrated skewness and kurtosis. Performance data from the CTBT stations is very high. Signal to noise ratio 〉1,000 after passing through the filter. Such riset conducted to find out a rapid magnitude estimations from predominant frequency of displacement are: log Td = 0.2406 M- 1.3665 (R = 0.73) or M = 4.156 log Td + 5.6797. Relationship of Pd, magnitude moment, Mw and hypocentre, R are log Pd = -4.684 + 0.815 Mw - 1.36 log R. For relation of PGA (peak ground acceleration) and amplitude displacement are log PGA = 1.117 log Pd + 0.728 (R = 0.91). Furthermore, this formula can be used to support earthquake early warning in west of Java. 展开更多
关键词 Earthquake early warning displacement peak ground acceleration.
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中值的测定:平均数
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作者 马富泉 《外国经济与管理》 1981年第2期37-39,共3页
绪言中值的测定(也指诸如集中趋势的测定或“平均数”的测定)通常较任何其它统计测定应用得更为广泛。引些例证:美国运输部的一份研究报告透露,一辆新购的汽车,由同一车主驾驶十年,每英里的平均费用为13.8美分。夫妇离婿生效日的平均年... 绪言中值的测定(也指诸如集中趋势的测定或“平均数”的测定)通常较任何其它统计测定应用得更为广泛。引些例证:美国运输部的一份研究报告透露,一辆新购的汽车,由同一车主驾驶十年,每英里的平均费用为13.8美分。夫妇离婿生效日的平均年龄分别为33.6岁与30.1岁。从1953年到1957年美国农场数每年平均减少107,650个。现年25岁的吸烟人平均将再活40.3年,而不吸烟的人更可多活8.3年即再活48.6年等等。常用四种平均数为:算术平均数、中位数、众数和几何平均数。 展开更多
关键词 算术平均数 几何平均数 组中值 统计测定 发行量 集中趋势 计算 研究报告 频数分布 吸烟
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社会经济统计学原理千题判断
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作者 И.С.帕斯哈维尔 陈仁恩 《统计》 1987年第1期6-6,共1页
本书译自1983年苏联出版的、供程序教学使用的《统计学概论习题汇编》的第二部分.该书的内容体系和我国现行的社会经济统计学原理教材基本一致.
关键词 社会经济统计 统计学原理 书译 程序教学 内容体系 分配数列 变异指标 统计测定 参考读物 动态数列
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Rapid determination of eight aristolochic acid analogues in five Aristolochiaceae plants by ultra-high performance liquid chromatography quadrupole/time-of-flight mass spectrometry 被引量:14
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作者 孔德强 高慧媛 +2 位作者 李辛 路金才 袁丹 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第6期364-375,共12页
Aristolochic acids (AAs) and aristololactams (ALs) are commonly found in some Aristolochiaceae plants, and they have been reported to be AA nephropathy (AAN), nephrotoxicity and carcinogenicity. In the present s... Aristolochic acids (AAs) and aristololactams (ALs) are commonly found in some Aristolochiaceae plants, and they have been reported to be AA nephropathy (AAN), nephrotoxicity and carcinogenicity. In the present study, we established an ultra high performance liquid chromatography (UHPLC) coupled with quadmpole/time-of-flight mass spectrometry (Q/TOF-MS) method for the rapid analysis of eight AA analogues in 19 samples originated from the five Aristolochiaceae plants, the roots and rhizomes ofAsarum sieboldii Miq. var. seoulense Nakai, the fruits ofAristolochia contorta Bunge or A. debilis Sieb. et Zucc., the roots ofAristolochia debilis Sieb. et Zucc., the stems ofAristolochia manshuriensis Kom., and the roots of Aristolochiafangchi Y. C. Wu ex L. D. Chou et S. M. Hwang. A total of five AAs and three ALs were identified by co-chromatography of sample extract and comparing the retention time, UV spectra, and characteristic molecular ions and fragment ions with those of authentic standards, or tentatively identified by MS/MS determination along with Mass Fragment software. Moreover, the method was validated for the simultaneous quantification or semi-quantification of them. The samples significantly differed in the quality and quantity of AA analogues, which aUowed the possibility of showing their chemical distinctness, and it might be helpful in their standardization and quality control. Furthermore, in order to holistically compare the difference between the five Aristolochiaceae plants, dataset obtained from UHPLC-Q/TOF-MS was processed with principal component analysis (PCA) and orthogonal partial least squared discriminant analysis (OPLS-DA). 展开更多
关键词 Aristolochic acids Aristololactams ARISTOLOCHIACEAE UHPLC-Q/TOF-MS Quantification Multivariate statistical analysis
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Determination of the limits for multivariate rational functions
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作者 XIAO ShuiJing ZENG GuangXing 《Science China Mathematics》 SCIE 2014年第2期397-416,共20页
The purpose of this paper is to solve the problem of determining the limits of multivariate rational functions.It is essential to decide whether or not limxˉ→0f g=0 for two non-zero polynomials f,g∈R[x1,...,xn]with... The purpose of this paper is to solve the problem of determining the limits of multivariate rational functions.It is essential to decide whether or not limxˉ→0f g=0 for two non-zero polynomials f,g∈R[x1,...,xn]with f(0,...,0)=g(0,...,0)=0.For two such polynomials f and g,we establish two necessary and sufcient conditions for the rational functionf g to have its limit 0 at the origin.Based on these theoretic results,we present an algorithm for deciding whether or not lim(x1,...,xn)→(0,...,0)f g=0,where f,g∈R[x1,...,xn]are two non-zero polynomials.The design of our algorithm involves two existing algorithms:one for computing the rational univariate representations of a complete chain of polynomials,another for catching strictly critical points in a real algebraic variety.The two algorithms are based on the well-known Wu’s method.With the aid of the computer algebraic system Maple,our algorithm has been made into a general program.In the final section of this paper,several examples are given to illustrate the efectiveness of our algorithm. 展开更多
关键词 rational function LIMIT infinitesimal element strictly critical point rational univariate represen-tation (RUR) Wu's method transfer principle
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