期刊文献+
共找到27篇文章
< 1 2 >
每页显示 20 50 100
Estimation of the Number of Collapsed Houses Damaged by Typhoon Based on Principal Components Analysis and Support Vector Machine 被引量:2
1
作者 张新厂 娄伟平 《Meteorological and Environmental Research》 CAS 2010年第4期11-14,共4页
The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of build... The evaluation model was established to estimate the number of houses collapsed during typhoon disaster for Zhejiang Province.The factor leading to disaster,the environment fostering disaster and the exposure of buildings were processed by Principal Component Analysis.The key factor was extracted to support input of vector machine model and to build an evaluation model;the historical fitting result kept in line with the fact.In the real evaluation of two typhoons landed in Zhejiang Province in 2008 and 2009,the coincidence of evaluating result and actual value proved the feasibility of this model. 展开更多
关键词 TYPHOON the number of collapsed houses Principal Components Analysis Support Vector Machine EVALUATION China
下载PDF
ON THE NUMBER OF EULERIAN PLANAR MAPS 被引量:7
2
作者 刘彦佩 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期418-423,共6页
This paper presents the number of combinatorially distinct rooted Eulerian planar maps with the number of non-root-vertices and the number of non-root-faces as two parameters. The parametric expressions for determinin... This paper presents the number of combinatorially distinct rooted Eulerian planar maps with the number of non-root-vertices and the number of non-root-faces as two parameters. The parametric expressions for determining the number in tha loopless Eulerian case are also obtained. 展开更多
关键词 ROOT ON the number of EULERIAN PLANAR MAPS
下载PDF
Mersenne Numbers, Recursive Generation of Natural Numbers, and Counting the Number of Prime Numbers 被引量:1
3
作者 Ramon Carbó-Dorca 《Applied Mathematics》 2022年第6期538-543,共6页
A simple recursive algorithm to generate the set of natural numbers, based on Mersenne numbers: M<sub>N</sub> = 2<sup>N</sup> – 1, is used to count the number of prime numbers within the preci... A simple recursive algorithm to generate the set of natural numbers, based on Mersenne numbers: M<sub>N</sub> = 2<sup>N</sup> – 1, is used to count the number of prime numbers within the precise Mersenne natural number intervals: [0;M<sub>N</sub>]. This permits the formulation of an extended twin prime conjecture. Moreover, it is found that the prime numbers subsets contained in Mersenne intervals have cardinalities strongly correlated with the corresponding Mersenne numbers. 展开更多
关键词 Mersenne numbers Recursive Generation of Natural numbers Mersenne Natural number Intervals Counting the number of Prime numbers in Mersenne Natural Intervals Correlation between Prime number Set Cardinalities and Mersenne numbers Extended Twin Prime number Conjecture
下载PDF
Calculation and analysis of the number of return photons from sodium laser beacon excited by the long pulse laser with circular polarization
4
作者 刘向远 钱仙妹 +1 位作者 李玉杰 饶瑞中 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期240-248,共9页
The number of return photons from sodium laser beacon(SLB) greatly suffers down-pumping, recoil, and geomagnetic field when the long pulse laser with circular polarization interacts with sodium atoms in the mesosphe... The number of return photons from sodium laser beacon(SLB) greatly suffers down-pumping, recoil, and geomagnetic field when the long pulse laser with circular polarization interacts with sodium atoms in the mesosphere. Considering recoil and down-pumping effects on the number of return photons from SLB, the spontaneous radiation rates are obtained by numerical computations and fittings. Furthermore, combining with the geomagnetic field effects, a new expression is achieved for calculating the number of return photons. By using this expression and considering the stochastic distribution of laser intensity in the mesosphere under different turbulence models for atmosphere, the number of return photons excited by the narrow-band single mode laser and that by the narrow-band three-mode laser are respectively calculated. The results show that the narrow-band three-mode laser with a specific spectrum structure has a higher spontaneous radiation rate and more return photons than a narrow-band single mode laser. Of note, the effect of the atmospheric turbulence on the number of return photons is remarkable. Calculation results indicate that the number of return photons under the HV5/7 model for atmospheric turbulence is much higher than that under the Greenwood and Mod HV models. 展开更多
关键词 sodium laser beacon spontaneous radiation rates the number of return photons down-pumping recoil geomagnetic field
下载PDF
IS THE“DEGREE OF AGGREGATION”A FUNCTION OF THE AVERAGE AGGREGATE NUMBER,OR OF THE NUMBER OF AGGREGATES,OR BOTH?
5
作者 Xi Kui JIANG Jin Tao ZHANG Shanghai Institute of Organic Chemistry,Academia Sinica,345 Ling-ling LU,Shanghai 200032 Zhen He TONG Laboratory of Photochemistry,Institute of Photographic Chemistry,Academia Sinica,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第9期675-676,共2页
Measurement of the average aggregate number of coaggregates(N_co)and evaluation Of the number of coaggregates([CoAg])in the region of increasing degree of aggregation shows that only N_co increases linearly with the c... Measurement of the average aggregate number of coaggregates(N_co)and evaluation Of the number of coaggregates([CoAg])in the region of increasing degree of aggregation shows that only N_co increases linearly with the concentration of the target molecules CE-In and BL-ol. 展开更多
关键词 Menger A FUNCTION of the AVERAGE AGGREGATE number OR of the number of AGGREGATES OR BOTH DEGREE of AGGREGATION IS the Figure OC
下载PDF
Influence of the Number of Reserved Fruit on Fruit-bearing Branch of Early-maturing Citrus unshiu Marc. on Fruit Growth and Development
6
作者 周光萍 金方伦 +5 位作者 万敏 黎明 杨李娟 敖学熙 韩成敏 徐琼 《Agricultural Science & Technology》 CAS 2014年第2期238-242,共5页
In order to provide theoretical references for early-maturing Citrus unshiu Marc. in terms of fruit thinning, timely fertilization and harvesting, as wel as for for-mulation of of Early-maturing Citrus unshiu Marc. Cu... In order to provide theoretical references for early-maturing Citrus unshiu Marc. in terms of fruit thinning, timely fertilization and harvesting, as wel as for for-mulation of of Early-maturing Citrus unshiu Marc. Cultivation Technique Standards in Guizhou Province, the dynamic changes of fruit longitudinal diameter and trans-verse diameter of 11-year-old and 12-year-old early maturing Citrus unshiu Marc. were tested in two consecutive years and the effects of single-fruit bearing branch on fruit growth and development were compared. The results showed annual varia-tion of longitudinal and transverse diameter of the fruit in Guizhou grew faster at the beginning and then slowed down gradual y, maintaining a slow-growth period after October; the growth curve final y was flat in mature stage. General y, the growth and development stage of fruit showed four growth peaks, showing an in-creasing S-shape curve and fruit net increase also had four growth peaks with a double S-shape curve. Specifical y, longitudinal diameters growth alternated with transverse diameter growth and the former proved much stronger. In terms of ef-fects of single-fruit bearing branch on longitudinal and transverse diameter growth, the number of reserved fruits had direct effects on the growth, net increase of weight, time of growth peak, fluctuation and the number of growth peak. The growth and development, and quality of fruits in the treatments with two or three fruits re-served on single fruit-bearing branch proved better compared with the control with four left fruits. It suggested that early June and early July are the best time for fer-tilization of early-maturing Citrus unshiu Marc. in Guizhou Pprovince and would have better effect if combined with foliage spraying. The suitable harvest time is in the end of October. The preferred number of reserved fruit on single fruit-bearing branch is 2-3. In actual production, the implementation of flower and fruit thinning should also takes tree age, balance of tree vigor, strength of fruit bearing branch, alternate bearing phenomenon and other factors into consideration. 展开更多
关键词 Citrus unshiu Marc. Early-maturing cultivar FRUIT Growth and develop-ment Fruit-bearing branch the number of reserved fruit
下载PDF
Factors Influencing the Number of Rabies Cases in Children in China
7
作者 SONG Miao TANG Qing +3 位作者 Rayner Simon TAO Xiao Yan SHEN Xin Xin LIANG Guo Dong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第8期627-632,共6页
To understand the epidemic situation and factors influencing rabies cases in children in China, we obtained an overview of the current epidemic based on individual data of rabies cases in children and a descriptive an... To understand the epidemic situation and factors influencing rabies cases in children in China, we obtained an overview of the current epidemic based on individual data of rabies cases in children and a descriptive analysis was carried on the prevalence and related factors. The results showed that the rabies cases in children accounted for 21.3% of the total number of rabies cases in China, 97.0% of these cases occurred in rural areas, they were mainly caused by dogs (81.5%), and were primarily level Ill exposure (47.7%). More than half of the cases were not treated with wound care, vaccination rate was extremely low (15.7%), and only 5.9% of cases were injected with antibodies. Furthermore, 25.4% of cases adopted incorrect treatments such as extruding bleed and wound closure, cases vaccinated with 5 injections acco- unted for only 22.5%. In conclusion, the prevalence of rabies cases in children in China remains a serious concern, the number and immune status of dogs in rural areas, and knowledge of rabies by risk populations should be considered in future rabies prevention and control programs. 展开更多
关键词 In Factors Influencing the number of Rabies Cases in Children in China
下载PDF
A Note on Single-Machine Lot Scheduling with Splittable Jobs to Minimize the Number of Tardy Jobs
8
作者 SHEN Hui-jun GENG Zhi-chao 《Chinese Quarterly Journal of Mathematics》 2022年第4期412-421,共10页
The single-machine lot scheduling problem with splittable jobs to minimize the number of tardy jobs has been showed to be weakly NP-hard in the literature.In this paper,we show that a generalized version of this probl... The single-machine lot scheduling problem with splittable jobs to minimize the number of tardy jobs has been showed to be weakly NP-hard in the literature.In this paper,we show that a generalized version of this problem in which jobs have deadlines is strongly NP-hard,and also present the results of some related scheduling problems. 展开更多
关键词 Lot scheduling the number of tardy jobs Splitting jobs Strongly NP-hard
下载PDF
Annual change of the number of anaerobic sulf ite reducing bacteria in sediment of the Daya Bay
9
作者 Zhou Zongcheng, Ni Chunzhi, Zeng Huoshui, Yao Ruimei, Cai Ziping, Lin Yanshun, Liang Ziyuan and Gu Jingyu Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第3期441-447,共7页
<Abstrat>The surface sediment samples were collected month by month at nine stations in the Daya Bay from January to December 1987, and the number of anaerobic sulfite reducing bacteria and their spores and the ... <Abstrat>The surface sediment samples were collected month by month at nine stations in the Daya Bay from January to December 1987, and the number of anaerobic sulfite reducing bacteria and their spores and the regularity of seasonal change were determined. The effect of environmental factors, water temperature and the resoluble oxygen concentration in the bottom of seawater on the number of them were discussed. The results show that the number of anaerobic su|fite reducing bacteria were low in sediment of the Daya Bay, indicating that the hay was less contaminated. 展开更多
关键词 Annual change of the number of anaerobic sulf ite reducing bacteria in sediment of the Daya Bay
下载PDF
The Number of Five Basic Elements' Motion of Traditional Chinese Medicine and Cancer Prediction
10
作者 Hanyi Zhang 《Journal of Advances in Medicine Science》 2020年第2期26-30,共5页
"The number of five basic elements'motion"varies according to the date of birth,which is tightly tied to human health.To predict cancer with"the number of five basic elements'motion"is simp... "The number of five basic elements'motion"varies according to the date of birth,which is tightly tied to human health.To predict cancer with"the number of five basic elements'motion"is simple,accurate,worth of research and popularizing.The theory of“five basic elements'motion and six climatic changes”is a key part of Traditional Chinese Medicine,“the number of five basic elements'motion”is strongly related to the physiology and pathology of human body.Combine with folk pathology prediction,“the number of five basic elements'motion”has been proved to have some scientific validity and of high accuracy in cancer prediction,it is worth to study,research and be discussed in-depth. 展开更多
关键词 the number of five basic elements'motion Cancer prediction Congenital pathology Acquired pathology
下载PDF
The Impact of Incentives on the Number of Suppliers
11
作者 Yueqiang LIU Huajie JIANG 《Journal of Systems Science and Information》 CSCD 2023年第3期349-364,共16页
In the context of adulteration by suppliers,downstream firms need to choose between incentives and regulation to ensure product quality.Studies have shown that the adulteration behavior of suppliers increases with the... In the context of adulteration by suppliers,downstream firms need to choose between incentives and regulation to ensure product quality.Studies have shown that the adulteration behavior of suppliers increases with the degree of dispersion of suppliers,that is,the number of suppliers increases.Therefore,based on the assumption that the number of suppliers impacts quality uncertainty,this paper further introduces the number of suppliers into the incentive model to investigate the relationship between supply chain dispersion,that is,the number of suppliers,social integrity,and incentive strength.The study finds that the optimal number of suppliers depends on social integrity,regulatory cost,and incentive strength.There is a positive correlation between social integrity and the number of suppliers,while regulatory costs and incentive strength have a negative correlation with the number of suppliers.That means,the higher the social integrity,the lower the regulatory cost;and the lower the incentive intensity,the more optimal suppliers can be selected. 展开更多
关键词 agency theory the number of suppliers incentive intensity social integrity regulatory costs
原文传递
Finite p-Groups in Which the Number of Subgroups of Possible Order Is Less Than or Equal to p^3 被引量:8
12
作者 Haipeng QU Ying SUN Qinhai ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第4期497-506,共10页
In this paper, groups of order p^n in which the number of subgroups of possible order is less than or equal to p3 ale classified. It turns out that if p 〉 2, n≥ 5, then the classification of groups of order p^n in w... In this paper, groups of order p^n in which the number of subgroups of possible order is less than or equal to p3 ale classified. It turns out that if p 〉 2, n≥ 5, then the classification of groups of order p^n in which the number of subgroups of possible order is less than or equal to p3 and the classification of groups of order p^n with a cyclic subgroup of index p2 are the same. 展开更多
关键词 Inner abelian p-groups Metacyclic p-groups Groups of order p^n with a cyclic subgroup of index p^2 the number of subgroups
原文传递
Method for determining number of coherent signals in the presence of colored noise
13
作者 Jiaqi Zhen, Xicai Si, and Lutao Liu College of Information & Communication Engineering, Harbin Engineering University, Harbin 150001, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期27-30,共4页
The approach of estimating the number of signals based on information theoretic criteria has good performance in the assumption of white noise, but it always leads to false estimation of the coherent sources in colore... The approach of estimating the number of signals based on information theoretic criteria has good performance in the assumption of white noise, but it always leads to false estimation of the coherent sources in colored noise. An approach combining the combined information theoretic criteria and eigen- value correction, is presented to determine number of signals. The method uses maximum likelihood (ML) and information theoretic criteria to estimate coherent signals alternately, then eliminate the inequality of the eigenvalues caused by colored noise by correcting the noise eigenvalues. The computer simulation results prove the effective performance of the method. 展开更多
关键词 determining the number of signals coherent signals colored noise information theoretic criteria.
下载PDF
A Study on Social Choice Making:the Number of Admissible Preference Orderings for SMV
14
作者 LUO Yunfeng XIAO Renbin YUE Chaoyuan Institute of Systems Engineering, Huazhong University of Science and Technology 《Systems Science and Systems Engineering》 CSCD 1993年第4期318-325,共8页
In this paper, we study, mathematically speaking, the problem-the number of admissible preference orderings for the transitivity of simple majority vote(SMV) derived from Arrow’s Impossibility Theorem. In our researc... In this paper, we study, mathematically speaking, the problem-the number of admissible preference orderings for the transitivity of simple majority vote(SMV) derived from Arrow’s Impossibility Theorem. In our research, we find, by computer enumerating, that some results given by Craven are not correct. By defining a set of constraints, we give the recurrence formula of the local maximal number of admissible preference orderings and some other useful results. 展开更多
关键词 the number of admissible preference orderings simple majority vote(SMV) conditions of transitivity for SMV the recurrence formula.
原文传递
On the Number of Finite Non-isomorphic Abelian Groups in Short Intervals
15
作者 曹晓东 《Chinese Science Bulletin》 SCIE EI CAS 1994年第7期615-616,共2页
Let the arithmetic function a(n) denote the number of non-isomorphic Abeliangroups of order n;k, positive integer, and x≥0. We setA_k(x)= sum from n≤x a(n)=k to (1)andA_k(x;h) =A_k(x+h)-A_k(x). A. Ivice first invest... Let the arithmetic function a(n) denote the number of non-isomorphic Abeliangroups of order n;k, positive integer, and x≥0. We setA_k(x)= sum from n≤x a(n)=k to (1)andA_k(x;h) =A_k(x+h)-A_k(x). A. Ivice first investigated the distribution of the values of finite non-isomorphicAbelian groups in short intervals. E. Kratzel reduced the problem to estimate theerror term △(1, 2, 3;x) in the three-dimensional multiplicative problem, and furtherimproved Ivice’s result. 展开更多
关键词 On the number of Finite Non-isomorphic Abelian Groups in Short Intervals
原文传递
Can Raising the Tobacco Tax Reduce the Number of Smokers?
16
《Beijing Review》 2009年第6期46-47,共2页
Experts from China’s State Administration of Taxation and the University of California,Berkeley unveiled a report,"Tobacco Tax and Its Potential Impact on China,"
关键词 Can Raising the Tobacco Tax Reduce the number of Smokers
原文传递
Estimation of Number Of Small Cattle Through ARIMA Models in Turkey
17
作者 Senol CELIK 《Journal of Mathematics and System Science》 2015年第11期464-473,共10页
In this study, the number of sheep and goats in Turkey were analysed by time series analysis method, and the number of great cattle for next years predicted through the most appropriate time series model.Time series w... In this study, the number of sheep and goats in Turkey were analysed by time series analysis method, and the number of great cattle for next years predicted through the most appropriate time series model.Time series was formed using the data on the number of sheep and goats belonging to the period between 1930 and 2014 in Turkey It was determined through autocorrelation function graphic that the series weren't stationary at first, but they became stationary after their first difference were calculated. A stagnancy test was performed through extended Dickey-Fuller test. So as to determine the suitability of the model, it was reviewed if autocorrelation and partial autocorrelation graphs were white noise series and also the results of Box-Ljung test were reviwed. Through the "tested models, the model estimations, of which parameter estimates were significant and Akaike information criterion (AIC) was the smallest, were performed. The most appropriate model in terms of both the number of sheep and goats is first-level integrated moving average model stated as ARIMA(0,1,1). In this model, it was estimated that there would be an increase in the number of sheep and goats in Turkey between the years of 2015 and 2020, however, the increase in the number of sheep would be more than the increase in the number of goats. 展开更多
关键词 ARIMA Models AUTOCORRELATION the number of sheep the number of goats.
下载PDF
Studies of Thermodynamic Properties and Relative Stability of Polybrominated Xanthones by Density Functional Theory 被引量:3
18
作者 单刚 李秀菊 +1 位作者 王遵尧 杨郭英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第2期225-232,共8页
The thermodynamic properties of xanthone(XTH) and 135 polybrominated xanthones(PBXTHs) in the standard state have been calculated at the B3LYP/6-31G* level using Gaussian 03 program.The isodesmic reactions were d... The thermodynamic properties of xanthone(XTH) and 135 polybrominated xanthones(PBXTHs) in the standard state have been calculated at the B3LYP/6-31G* level using Gaussian 03 program.The isodesmic reactions were designed to calculate the standard enthalpy of formation(△fHθ) and standard free energy of formation(△fGθ) of PBXTH congeners.The relations of these thermodynamic parameters with the number and position of Br atom substitution(NPBS) were discussed,and it was found that there exist high correlation between thermodynamic parameters(entropy(Sθ),△fHθ and △fGθ) and NPBS.According to the relative magnitude of their △fGθ,the relative stability order of PBXTH congeners was theoretically proposed.The relative rate constants of formation reactions of PBXTH congeners were calculated,Moreover,the values of molar heat capacity at constant pressure(Cp,m) from 200 to 1000 K for PBXTH congeners were also calculated,and the temperature dependence relation of them was obtained,suggesting very good relationships between Cp,m and temperature(T,T^1 and T^2) for almost all PBXTH congeners. 展开更多
关键词 polybrominated xanthone the number and position of Br atom substitution(NPBS) thermodynamic property relative stability molar heat capacity at constant pressure(Cp m)
下载PDF
Studies of Structural and Thermodynamic Properties for Polychlorinated Thianthrenes by Density Functional Theory 被引量:1
19
作者 刘辉 孙萍 +2 位作者 柳红霞 王遵尧 王连生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1255-1260,共6页
The structural and thermodynamic (PCTAs) in the ideal gas state at 298.15 K and 1.013 properties of 75 polychlorinated thianthrenes ×10^5 Pa have been calculated at the B3LYP/6- 31G* level using Gaussian 98 pr... The structural and thermodynamic (PCTAs) in the ideal gas state at 298.15 K and 1.013 properties of 75 polychlorinated thianthrenes ×10^5 Pa have been calculated at the B3LYP/6- 31G* level using Gaussian 98 program. Based on the output data of Gaussian, the isodesmic reactions were designed to calculate standard enthalpy of formation (△fH^θ) and standard free energy of formation (△fH^θ) of PCTAs congeners. The relations of these thermodynamic parameters with the number and position of C1 atom substitution (Npcs) were discussed, and it was found that there exists high correlation between thermodynamic parameters (total energy (TE), zero-point vibrational energy (ZPE), thermal correction to energy (Eth), heat capacity at constant volume (Cv^θ), entropy (S^θ), enthalpy (H^θ), free energy (G^θ), standard enthalpies of formation (△fH^θ) and standard Gibbs energies of formation (△fG^θ)) and Npcs. On the basis of the relative magnitude of their △fG^θ, the order of relative stability of PCTA congeners was theoretically proposed. In addition, the correlations between structural parameters and Npcs were also discussed. The good correlations were found between molecular average polarizability (α), energy of the highest occupied molecular orbital (EHOMO), molecular volume (Vm) and Npcs, and all R^2 values are larger than 0.95. Moreover, it was supposed that the isomer groups with higher toxicity should be Tri-CTA and TCTA. 展开更多
关键词 polychlorinated thianthrenes density functional theory (DFT) the number and position of CI atom substitution (Npcs) structural and thermodynamic parameters relative stability
下载PDF
A Comparative Analysis on Testing Stability of Seed Coat Neps (SCN) Number and Size with AFIS and Premier aQura
20
作者 王毅 鲁琴 +2 位作者 孙鹏子 郭昕 曹继鹏 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期528-532,共5页
This paper makes a comparative analysis of testing stability of seed coat neps (SCN) number and size with Advanced Fiber Information System (AFIS) and aQura.After testing the number and size of SCN in sliver produced ... This paper makes a comparative analysis of testing stability of seed coat neps (SCN) number and size with Advanced Fiber Information System (AFIS) and aQura.After testing the number and size of SCN in sliver produced by two different experiments (twelve plans in each experiment)with AFIS and aQura,the test results are analyzed with the theory of statistical analysis and the following conclusions are drawn:(1) the testing stability of SCN number and size of aQura is better than that of AFIS;(2) to get a reliable testing stability of SCN number,more than 24 samples should be tested on aQura,while more than 130 samples on AFIS;(3) for SCN size test,more than 10 and 12 samples should be tested on aQura and AFIS,respectively;(4) the basic reason for higher testing stability of SCN number and size on aQura is that the weight of the samples is greater than that on AFIS. 展开更多
关键词 uster AF1S: premier aQura the number andsize of SCN test
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部