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在概率论与数理统计教学中的思考与研究 被引量:3
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作者 丁箭飞 李旭红 《科技信息》 2013年第11期218-218,共1页
本文结合实际本科教学,分析了当前概率论与数理统计教学所遇到的一些问题,并提出几点关于教学改革的建议或教学技巧。
关键词 概率论与数量统计 实例应用 对比教学
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A Note on a Misuirewicz's Theorem
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作者 周作领 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期12-15,共4页
In this paper,we improve a Misuirewicz's theorem and give a new proof of small conjecture on topological entropy.
关键词 continuous self-map measure-preserving system topological entropy invariant measure
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Variation on Wild Sunflower (Helianthus ruderalis L.) for Quantitative and Qualitative Parameters 被引量:2
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作者 S. A. Aliu S. Sh. Fetahu S. Xh. Kaqiu H. E. Bytyci 《Journal of Agricultural Science and Technology》 2010年第3期11-17,共7页
Our expedition have identified location in the central part of Kosovo where were collected a samples (accessions) at coordinates; Sub-Locality SL-1 (N42°34′36″, E21°07′45″), altitude 574 m, SL-2 (N4... Our expedition have identified location in the central part of Kosovo where were collected a samples (accessions) at coordinates; Sub-Locality SL-1 (N42°34′36″, E21°07′45″), altitude 574 m, SL-2 (N42°34′29″, E 21°07′45″altitude 591 m and SL-3 (N42°34′30″, E21°07′46″) on altitude 565 m. The aim of present investigation was carried out to study genetic variability of quantitative and qualitative parameters. The populations from SL-2 were characterized of higher significance on seed oil (23.74%) and protein content (16.74%). The estimation average value of seed protein and oil content was 15.52% and 23.48% respectively. The variability of plant height ranged from 182.33 cm to as much as 200.89 cm, while distinction's between them were + 18.56 cm which was a significant higher at P〈0.05 probability level. The SL-3 showed the higher value of HWK (34.6 g), head per plant (39.33) and head diameter (9.5 cm) but, was characterized significantly lowest on seed protein content (13.99%). The all traits included in our investigations showed a higher genetic variability with majority of extreme values. The sunflower populations differed significantly in several parameters measured, they have a different genetic and morphological backgrounds. Results from wild sunflower form indicated notable differences in dispersion of important genes for different traits and showed the potential for using in future for breeding program. 展开更多
关键词 SUNFLOWER ACCESSION quantitative parameters oil content protein content.
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A New Statistical Tool: Scalar Score Function
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作者 Zdenek Fabian 《Computer Technology and Application》 2011年第2期109-116,共8页
The basic inference function of mathematical statistics, the score function, is a vector function. The author has introduced the scalar score, a scalar inference function, which reflects main features of a continuous ... The basic inference function of mathematical statistics, the score function, is a vector function. The author has introduced the scalar score, a scalar inference function, which reflects main features of a continuous probability distribution and which is simple. Its simplicity makes it possible to introduce new relevant numerical characteristics of continuous distributions. The t-mean and score variance are descriptions of distributions without the drawbacks of the mean and variance, which may not exist even in cases of regular distributions. Their sample counterparts appear to be alternative descriptions of the observed data. The scalar score itself appears to be a new mathematical tool, which could be used in solving traditional statistical problems for models far from the normal one, skewed and heavy-tailed. 展开更多
关键词 STATISTICS inference function data characteristics point estimates heavy tails.
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A Robust Method for Ordering Performances of Multi-assets, Based Purely on Their Return Series 被引量:1
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作者 Ilknur Tulunay 《Journal of Mathematics and System Science》 2017年第11期316-333,共18页
This study propose a new robust method to rank the performances of multi-assets (portfolios), based purely on their return time series. This method makes no assumption on the distributions. Topsoe distance is symmet... This study propose a new robust method to rank the performances of multi-assets (portfolios), based purely on their return time series. This method makes no assumption on the distributions. Topsoe distance is symmetrized Kullback-Leibler divergence by average of the probabilities. The square root of Topsoe distance is a metric. We extend this metric from probability density functions to real number series on (0, 1 ]. We call it ST-metric. We show the consistency of ST-metric with mean-variance theory and stochastic dominance method of order one and two. We demonstrate the advantages of ST-metric over mean-variance rule and stochastic dominance method of order one and two. 展开更多
关键词 Topsoe distance metric Cross Entropy Relative Entropy Kullback-Leibler divergence Kullback-Leibler InformationCriterion (KLIC) portfolio performance portfolio management.
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Voice activity detection based on deep belief networks using likelihood ratio 被引量:3
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作者 KIM Sang-Kyun PARK Young-Jin LEE Sangmin 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第1期145-149,共5页
A novel technique is proposed to improve the performance of voice activity detection(VAD) by using deep belief networks(DBN) with a likelihood ratio(LR). The likelihood ratio is derived from the speech and noise spect... A novel technique is proposed to improve the performance of voice activity detection(VAD) by using deep belief networks(DBN) with a likelihood ratio(LR). The likelihood ratio is derived from the speech and noise spectral components that are assumed to follow the Gaussian probability density function(PDF). The proposed algorithm employs DBN learning in order to classify voice activity by using the input signal to calculate the likelihood ratio. Experiments show that the proposed algorithm yields improved results in various noise environments, compared to the conventional VAD algorithms. Furthermore, the DBN based algorithm decreases the detection probability of error with [0.7, 2.6] compared to the support vector machine based algorithm. 展开更多
关键词 voice activity detection likelihood ratio deep belief networks
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Lie Algebraic Approach to Energy Transfer for Collinear Collision of Two Anharmonic Diatomic Molecules
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作者 王晓艳 王鹏程 +4 位作者 邱建峰 王进喜 侯立霞 谢晋东 丁世良 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期339-343,共5页
An anharmonic oscillator algebra model is used to study the collinear collisions of two diatomic molecules. The transition probability for vibration-vibration energy transfer is presented. For an application of the me... An anharmonic oscillator algebra model is used to study the collinear collisions of two diatomic molecules. The transition probability for vibration-vibration energy transfer is presented. For an application of the method, we talk about the collision of N2+CO, N2+O2, and N2+N2. Through long time averaging, the transition probability changes to the function of total energy of the system. Comparing the results with the quantum results, we can see that the dynamical Lie algebraic method is useful for describing the anharmonie diatomic molecular collision. 展开更多
关键词 Lie algebraic ANHARMONIC energy transfer
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A numerical simulation of seepage structure surface and its feasibility 被引量:3
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作者 彭康 李夕兵 +1 位作者 王泽伟 刘爱华 《Journal of Central South University》 SCIE EI CAS 2013年第5期1326-1331,共6页
According to Cubic law and incompressible fluid law of mass conservation, the seepage character of the fracture surface was simulated with the simulation method of fractal theory and random Brown function. Furthermore... According to Cubic law and incompressible fluid law of mass conservation, the seepage character of the fracture surface was simulated with the simulation method of fractal theory and random Brown function. Furthermore, the permeability coefficient of the single fracture was obtained. In order to test the stability of the method, 500 simulations were conducted on each different fractal dimension. The simulated permeability coefficient was analyzed in probability density distribution and probability cumulative distribution statistics. Statistics showed that the discrete degree of the permeability coefficient increases with the increase of the fractal dimension. And the calculation result has better stability when the fractal dimension value is relatively small. According to the Bayes theory, the characteristic index of the permeability coefficient on fractal dimension P(Dfi| Ri) is established. The index, P(Dfi| Ri), shows that when the simulated permeability coefficient is relatively large, it can clearly represent the fractal dimension of the structure surface, the probability is 82%. The calculated results of the characteristic index verify the feasibility of the method. 展开更多
关键词 fractal theory numerical simulation representative elementary volume (REV) random brown function permeabilitycoefficient fractal dimension
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Characteristic Functions over C*-Probability Spaces
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作者 王勤 李绍宽 《Journal of Donghua University(English Edition)》 EI CAS 2003年第2期39-41,共3页
Various properties of the characteristic functions of random variables in a non-commutative C*-probability space are studied in this paper. It turns out that the distributions of random variables are uniquely determin... Various properties of the characteristic functions of random variables in a non-commutative C*-probability space are studied in this paper. It turns out that the distributions of random variables are uniquely determined by their characteristic functions. By using the properties of characteristic functions, a central limit theorem for a sequence of independent identically distributed random variables in a C*-probability space is established as well. 展开更多
关键词 non-commutative probability space C* -algebra random variable characteristic function central limit theorem
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Some Fixed Point Theorems on Nonarchimedean Menger Probabilistic Metrie Space
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作者 毛宝瑜 陈汝栋 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第2期50-55,共6页
In this paper,we have given a fixed point theorem for mapping sequence and mapping pair on nonarchimedean Mengen Probabilistic Metric space.A special case of its inference is an extension of results of reference [5-6].
关键词 nonarchimedean Mengen Probabilistc metnc space common fixed point.
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基于贝叶斯网络Noisy Or模型的水电机组故障诊断研究 被引量:16
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作者 胡勇健 肖志怀 +1 位作者 周云飞 孙召辉 《水力发电学报》 EI CSCD 北大核心 2015年第6期197-203,共7页
针对水电机组故障诊断中系统结构复杂,不确定因素众多的特点,将贝叶斯网络引入水电机组故障诊断中,建立基于贝叶斯网络的水电机组故障诊断系统;为了克服贝叶斯网络结构中需要的概率数量庞大和确定概率困难特点,在贝叶斯网络系统结构中引... 针对水电机组故障诊断中系统结构复杂,不确定因素众多的特点,将贝叶斯网络引入水电机组故障诊断中,建立基于贝叶斯网络的水电机组故障诊断系统;为了克服贝叶斯网络结构中需要的概率数量庞大和确定概率困难特点,在贝叶斯网络系统结构中引入Noisy Or模型。论文首先利用专家知识,将各个特征结点按二值结点构造网络,确定各单个结点的概率,然后计算多个结点的任意组合对结果的影响程度,从而确定某种故障发生的可能程度。仿真研究表明:用此模型构造的贝叶斯网络结构,需要的条件概率个数可以从2n减小为2n。大大降低了数据需求量,提高了水电机组故障诊断速度和效率。 展开更多
关键词 动力机械工程 水电机组故障诊断 贝叶斯网络 NOISY Or模型 概率数量
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Quantitative deterministic versus probability analyses based on a safety margin criterion 被引量:12
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作者 CHEN ZuYu CHEN LiHong +3 位作者 XU JiaCheng SUN Ping WU Chao WANG YuJie 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第10期1988-2000,共13页
This paper proposes a new criterion called the ratio of safety margin(RSM)for use in the areas of the global factor of safety,reliability and limit states analyses with reference to their respective allowable criteria... This paper proposes a new criterion called the ratio of safety margin(RSM)for use in the areas of the global factor of safety,reliability and limit states analyses with reference to their respective allowable criteria.An equation for calculating RSM based on the reliability index is formulated.Efforts for proving the applicability of this criterion include a theoretical demonstration in a simple one-variable case;an investigation on a test problem involving two random variables,followed by a slope stability study on a 156 m high embankment dam and an illustrative example presented in a EuroCode 7 guidebook.Calculation of the ratios of safety margin in the three areas provides a quantitative way to accommodate the analytical results within the same theoretical framework and makes the outcomes mutually comparable and supportive,which is much more enlightening than that would be the case by considering only one of them.Calculating RSMs for reliability and limit states methods has also helped solve the key issue concerning the uniqueness of the partial factors calibrated from a particular‘target case’. 展开更多
关键词 factor of safety reliability index partial factor ratio of safety margin embankment dam reliability analysis
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Return Probability of the Fibonacci Quantum Walk
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作者 CLEMENT AMPADU 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第8期220-224,共5页
In this paper the return probability of the one-dimensional discrete-time quantum walk is studied. We derive probabilistic formulas for the return probability related to the quantum walk governed by the Fibonacci coin.
关键词 return probability Fibonacci transformation quantum random walk
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Why Matter Occupies so Large a Volume?
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作者 E.B.Manoukian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第12期677-686,共10页
The paper represents a rigorous treatment of the underlying quantum theory, not just in words but providing the underlying technical details, as to why matter occupies so large a volume and its intimate connection wit... The paper represents a rigorous treatment of the underlying quantum theory, not just in words but providing the underlying technical details, as to why matter occupies so large a volume and its intimate connection with the Pauli exclusion principle, as more and more matter is put together, as well as of the contraction or shrinkage of "bosonic matter", upon collapse, for which the Panli exclusion is abolished. From the derived explicit bounds of integrals of powers of the particle number densities, explicit bounds on probabilities of the occurrences of the events just described are extracted. These probabilities lead one to infer the change of the "size" or extension of such matter, upon expansion or contraction, respectively, as their content is increased. 展开更多
关键词 expansion of matter and the Pauli exclusion principle contraction or shrinkage of "bosonic mat-ter" upon collapse
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Implicit Sampling,with Application to Data Assimilation
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作者 Alexandre J.CHORIN Matthias MORZFELD Xuemin TU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2013年第1期89-98,共10页
There are many computational tasks, in which it is necessary to sample a given probability density function (or pdf for short), i.e., to use a computer to construct a sequence of independent random vectors x~ (i --... There are many computational tasks, in which it is necessary to sample a given probability density function (or pdf for short), i.e., to use a computer to construct a sequence of independent random vectors x~ (i ---- 1, 2, ~ ~ ~ ), whose histogram converges to the given pdf. This can be difficult because the sample space can be huge, and more importantly, because the portion of the space, where the density is significant, can be very small, so that one may miss it by an ill-designed sampling scheme. Indeed, Markov- chain Monte Carlo, the most widely used sampling scheme, can be thought of as a search algorithm, where one starts at an arbitrary point and one advances step-by-step towards the high probability region of the space. This can be expensive, in particular because one is typically interested in independent samples, while the chain has a memory. The authors present an alternative, in which samples are found by solving an algebraic equation with a random right-hand side rather than by following a chain; each sample is independent of the previous samples. The construction in the context of numerical integration is explained, and then it is applied to data assimilation. 展开更多
关键词 Importance sampling Bayesian estimation Particle filter Implicit filter Data assimilation
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From strangelets to strange stars:a unified description
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作者 Cheng-Jun Xia Guang-Xiong Peng +1 位作者 En-Guang Zhao Shan-Gui Zhou 《Science Bulletin》 SCIE EI CAS CSCD 2016年第2期172-177,共6页
The conventionally separated treatments for strangelets and strange stars are now unified with a more comprehensive theoretical description for objects ranging from strangelets to strange stars. After constraining the... The conventionally separated treatments for strangelets and strange stars are now unified with a more comprehensive theoretical description for objects ranging from strangelets to strange stars. After constraining the model parameter according to the Witten–Bodmer hypothesis and observational mass–radius probability distribution of pulsars, we investigate the properties of this kind of objects. It is found that the energy per baryon decreases monotonically with increasing baryon number and reaches its minimum at the maximum baryon number, corresponding to the most massive strange star. Due to the quark depletion,an electric potential well is formed on the surface of the quarkpart. For a rotational bare strange star, a magnetic field with the typical strength in pulsars is generated. 展开更多
关键词 Strangelets Strange stars Strangequark matter Unified description Witten-Bodmerhypothesis
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