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从“爱因斯坦的速算”看速算式心算——探究常见的特定数和任意数乘法心算
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作者 张洪江 唐静馨 唐永巨 《新理财(公司理财)》 2004年第5期22-23,共2页
速算式心算法,一般分"特定数"和"任意数"两种.特定数心算是根据常见的数学公式推导成歌诀式速算法,使运算更简单、迅速;任意数心算是把算式化繁为简的方法,如两位数平方可用"补数法",两位数乘法可用"... 速算式心算法,一般分"特定数"和"任意数"两种.特定数心算是根据常见的数学公式推导成歌诀式速算法,使运算更简单、迅速;任意数心算是把算式化繁为简的方法,如两位数平方可用"补数法",两位数乘法可用"十字交叉法".所谓的化繁为简就是"变大为小,变复杂为简单". 展开更多
关键词 爱因斯坦 速算式心算 特定数 任意 乘法心算
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关于特定幸福4次方数列
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作者 高丽 赵喜燕 赵彩红 《吉首大学学报(自然科学版)》 CAS 2013年第5期1-2,共2页
利用初等方法对特定幸福4次方数列及特定幸福n次方数列进行了研究,给出并证明了关于集合F4的定理,并且得出特定幸福n次方数列相关问题的求解方法.
关键词 初等方法 特定幸福立方 特定幸福4次方
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关于特定幸福立方数列 被引量:1
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作者 韩迪 《郑州大学学报(理学版)》 CAS 北大核心 2012年第3期20-21,25,共3页
针对特定幸福立方数的一些问题进行研究,并对这些问题进行推广和延伸,给出了一般特定幸福k次方数的结论.
关键词 特定幸福立方 初等方法 特定幸福k次方
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让学生在游戏中玩转智趣数学
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作者 吴汝萍 《新教师》 2015年第10期40-41,共2页
一、让学生玩转教材中的智趣数学游戏打开小学数学教材,可以发现每册教材中都安排了不少的数学游戏活动,但因课堂教学时间有限,不少教师怎么也舍不得把时间花费在游戏过程中,往往将这类游戏活动题当成普通的数学练习题而简单处理。实际... 一、让学生玩转教材中的智趣数学游戏打开小学数学教材,可以发现每册教材中都安排了不少的数学游戏活动,但因课堂教学时间有限,不少教师怎么也舍不得把时间花费在游戏过程中,往往将这类游戏活动题当成普通的数学练习题而简单处理。实际上,儿童在游戏活动过程中,更能积极地探索与思考,会更有效地理解数学知识并获得轻松愉悦的学习体验。例如,一年级"10的分与合",教材中安排了这样的练习,实际上是一个"找朋友"游戏。 展开更多
关键词 游戏活动 小学学教材 课堂教学时间 学习体验 退位减法 进位加法 中都 特定数 书说 自编自导
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Censored Composite Conditional Quantile Screening for High-Dimensional Survival Data
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作者 LIU Wei LI Yingqiu 《应用概率统计》 CSCD 北大核心 2024年第5期783-799,共17页
In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all usef... In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all useful information across quantiles and can detect nonlinear effects including interactions and heterogeneity,effectively.Furthermore,the proposed screening method based on cCCQC is robust to the existence of outliers and enjoys the sure screening property.Simulation results demonstrate that the proposed method performs competitively on survival datasets of high-dimensional predictors,particularly when the variables are highly correlated. 展开更多
关键词 high-dimensional survival data censored composite conditional quantile coefficient sure screening property rank consistency property
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Characterizing uncertainty in pavement performance prediction 被引量:2
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作者 孙璐 葛敏莉 +1 位作者 顾文钧 徐冰 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期85-93,共9页
Taking variability and uncertainty involved in performance prediction into account, in order to make the prediction reliable and meaningful, a distribution-based method is developed to predict future PSI. This method,... Taking variability and uncertainty involved in performance prediction into account, in order to make the prediction reliable and meaningful, a distribution-based method is developed to predict future PSI. This method, which is based on the AASHTO pavement performance model, treats predictor variables as random variables with certain probability distributions and obtains the distribution of future PSI through the method of Monte-Carlo simulation. A computer program PERFORM using Monte Carlo simulation is developed to implement the numerical computation. Simulation results based on pavement and traffic parameters show that traffic, surface layer material property, and initial pavement performance are the most significant factors affecting pavement performance. Once the distribution of future PSI is determined, statistics such as the mean and the variance of future PSI are readily available. 展开更多
关键词 pavement performance VARIABILITY PREDICTION Monte Carlo simulation
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Comparative Study on VQ-Based Efficient Mandarin Speech Recognition Method
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作者 谢湘 赵军辉 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期266-270,共5页
A VQ based efficient speech recognition method is introduced, and the key parameters of this method are comparatively studied. This method is especially designed for mandarin speaker dependent small size word set r... A VQ based efficient speech recognition method is introduced, and the key parameters of this method are comparatively studied. This method is especially designed for mandarin speaker dependent small size word set recognition. It has less complexity, less resource consumption but higher ARR (accurate recognition rate) compared with traditional HMM or NN approach. A large scale test on the task of 11 mandarin digits recognition shows that the WER(word error rate) can reach 3 86%. This method is suitable for being embedded in PDA (personal digital assistant), mobile phone and so on to perform voice controlling like digits dialing, name dialing, calculating, voice commanding, etc. 展开更多
关键词 speech recognition vector quantization(VQ) speaker dependent digits recognition
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编码字典模式及用法
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作者 蒋富瑞 《山东科学》 CAS 1989年第2期1-3,共3页
本文讨论了减少编码字典数据冗余度的途径,认为:将大字典库合理地分解成若干小字典库,提高通用性,并改进用法,可明显减少冗余度。
关键词 编码字典 据冗余度 子库 存贮空间 字符型 编码长度 特定数 在原 分散性 据库文件
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一种新的卫生管理方法——危险性方法
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作者 王济东 《中国医院管理》 1983年第6期56-57,共2页
1981年世界卫生组织“危险性方法”特别工作组,介绍了他们正在部分发展中国家采用的一种新的卫生管理方法——危险性方法。现将其原理及步骤简单作一介绍。在社会人群中。
关键词 危险性因素 管理方法 卫生保健 卫生服务 组织管理 卫生人员 卫生工作 特定数 培训计划 保健系统
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摩尔是物质的什么单位?
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作者 杨国铨 《佛山师专学报》 1985年第1期106-109,共4页
1971年10月第14届国际计量会议决定,在国际单位制中站加第七个基本单位——摩尔。摩尔是由克分子发展而来的,它起着统一克分子、克原子和克离子的作用,同时把物理学上的光子、电子及其它粒子和粒子群的量也概括在内。但是对摩尔的概念... 1971年10月第14届国际计量会议决定,在国际单位制中站加第七个基本单位——摩尔。摩尔是由克分子发展而来的,它起着统一克分子、克原子和克离子的作用,同时把物理学上的光子、电子及其它粒子和粒子群的量也概括在内。但是对摩尔的概念直到现在国内外学者在文字叙述上却有不同。本文先将国内外学者对摩尔的概念加以介绍然后谈谈我个人的看法。 展开更多
关键词 摩尔 阿佛加德罗 克式量 国际计量大会 原子 原体 缩写符号 目的物 化学原理 特定数
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Analysis of Quantitative Trait Loci for Starch Properties of Rice Based on an RIL Population 被引量:11
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作者 包劲松 Harold CORKE +1 位作者 何平 朱立煌 《Acta Botanica Sinica》 CSCD 2003年第8期986-994,共9页
Rice (Oryza sativa L.) eating and cooking quality is mainly influenced by its starch properties. Mapping quantitative trait loci (QTL) for starch properties not only helps us understand their genetic basis leading to ... Rice (Oryza sativa L.) eating and cooking quality is mainly influenced by its starch properties. Mapping quantitative trait loci (QTL) for starch properties not only helps us understand their genetic basis leading to acceleration of quality improvement, but also helps us find possible genes participating in the synthesis of starch. A recombinant inbred line (RIL) population consisting of 107 lines, derived from an indica (Zaiyeqing 8, ZYQ 8) and a japonica (Jingxi 17, JX 17) rice, was used to investigate the genetic factors affecting starch quality parameters, such as apparent amylose content (AAC), gel consistency (GC), starch pasting viscosity parameters, gel textural properties, gelatinization temperature (GT) and starch retrogradation properties. A total of 44 QTLs covered chromosomes 2-6, 8, 9 and 11 were detected for the 22 traits, with at least one QTL and as many as four QTLs for each individual trait. The results indicated that two major genes were responsible for most starch property traits. The Wx gene that encodes granule bound starch synthase on chromosome 6 was significant for AAC, GC, starch pasting viscosity parameters, gel textural properties and starch retrogradation properties. The alk gene linked with Wx on chromosome 6 was significant for starch gelatinization temperature characteristics. All other QTLs were minor genes. One QTL on chromosome 9 flanked by RZ404 and G295 was significant for gel hardness (HD), gumminess (GUM), chewiness (CHEW), peak temperature of retrogradated starch (RTp), and percentage retrogradation (R%) and all these traits were not tested before. 展开更多
关键词 ALK eating and cooking quality quantitative trait locus RICE STARCH WX
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Allometric equations for estimating leaf area index(LAI) of two important tropical species(Tectona grandis and Dendrocalamus strictus) 被引量:2
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作者 Dhaval Vyas Nirav mehta +1 位作者 J.Dina-karan N.S.R.Krishnayya 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期197-200,I0006,共5页
Leaf area index(LAI) of Teak(Tectona grandis) and Bamboo(Dendrocalamus strictus) grown in Shoolpaneshwar Wildlife Sanctuary of Narmada District,Gujarat,India was obtained by destructive sampling,photo-grid metho... Leaf area index(LAI) of Teak(Tectona grandis) and Bamboo(Dendrocalamus strictus) grown in Shoolpaneshwar Wildlife Sanctuary of Narmada District,Gujarat,India was obtained by destructive sampling,photo-grid method and by litter trap method.An allometric equation(between leaf area by litter trap method and canopy spread area) was developed for the determination of LAI.Results show that LAI value calculated by the developed allometric equation was similar to that estimated by destructive sampling and photo-grid method,with Root Mean Square Error(RMSE) of 0.90 and 1.15 for Teak,and 0.38 and 0.46 for Bamboo,respectively.There was a perfect match in both the LAI values(estimated and calculated),indicating the accuracy of the developed equations for both the species.In conclusion,canopy spread is a better and sensitive parameter to estimate leaf area of trees.The developed equations can be used for estimating LAI of Teak and Bamboo in tropics. 展开更多
关键词 BAMBOO canopy spread area leaf area index specific leaf area TEAK tropical forest
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On the structural features of fiber suspensions in converging channel flow 被引量:6
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作者 林建忠 张凌新 《Journal of Zhejiang University Science》 EI CSCD 2003年第4期400-406,共7页
The structural features of fiber suspensions are dependent on the fiber alignment in the flows. In this work the orientation distribution function and orientation tensors for semi-concentrated fiber suspensions in ... The structural features of fiber suspensions are dependent on the fiber alignment in the flows. In this work the orientation distribution function and orientation tensors for semi-concentrated fiber suspensions in converging channel flow were calculated, and the evolutions of the fiber alignment and the bulk effective vis-cosity were analyzed. The results showed that the bulk stress and the effective viscosity were functions of therate-of-strain tensor and the fiber orientation state ; and that the fiber suspensions evolved to steady alignment and tended to concentrate to some preferred directions close to but not same as the directions of local stream-lines. The bulk effective viscosity depended on the product of Reynolds number and time. The decrease of ef-fective viscosity near the boundary benefited the increase of the rate of flow. Finally when the fiber alignment went into steady state, the structural features of fiber suspensions were not dependent on the Reynolds numberbut on the converging channel angle. 展开更多
关键词 Fiber suspensions Orientation distribution Effective viscosity Converging channel flow
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Precise asymptotics in the law of the logarithm for random fields in Hilbert space 被引量:1
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作者 FU Ke-ang ZHANG Li-xin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第4期651-659,共9页
Consider the positive d-dimensional lattice Z^d(d≥2) with partial ordering ≤, let {XK; K∈Z+^d} be i.i.d, random variables taking values in a real separable Hilbert space (H, ||·||) with mean zero and ... Consider the positive d-dimensional lattice Z^d(d≥2) with partial ordering ≤, let {XK; K∈Z+^d} be i.i.d, random variables taking values in a real separable Hilbert space (H, ||·||) with mean zero and covariance operator ∑ and set partial sums SN =∑K≤nXK,K,N∈Z+^d. Under some moment conditions, we obtain the precise asymptotics of a kind of weighted infinite series for partial sums SN as ε↓ by using the truncation and approximation methods. The results are related to the convergence rates of the law of the logarithm in Hilbert space, and they also extend the results of (Gut and Spataru, 2003). 展开更多
关键词 The law of the logarithm Random field Hilbert space. Tail probabilitv. Truncation method
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The Character and Formation of Elongated Depressions on the Upper Bulgarian Slope 被引量:2
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作者 XU Cuiling GREINERT Jens +3 位作者 HAECKEL Matthias BIALAS Jorg DIMITROV Lyubomir ZHAO Guangtao 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期555-562,共8页
Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depress... Seafloor elongated depressions are indicators of gas seepage or slope instability. Here we report a sequence of slopeparallel elongated depressions that link to headwalls of sediment slides on upper slope. The depressions of about 250 m in width and several kilometers in length are areas of focused gas discharge indicated by bubble-release into the water column and methane enriched pore waters. Sparker seismic profiles running perpendicular and parallel to the coast, show gas migration pathways and trapped gas underneath these depressions with bright spots and seismic blanking. The data indicate that upward gas migration is the initial reason for fracturing sedimentary layers. In the top sediment where two young stages of landslides can be detected, the slopeparallel sediment weakening lengthens and deepens the surficial fractures, creating the elongated depressions in the seafloor supported by sediment erosion due to slope-parallel water currents. 展开更多
关键词 methane seepage elongated depression POCKMARK LANDSLIDE Black Sea
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HRM and Quantitatives: Decision Tree and Vector Analysis in HRM Theory 被引量:2
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作者 Gurhan Uysal 《Chinese Business Review》 2014年第6期382-387,共6页
Research topic of this paper is to discuss theory of Human Resources Management (HRM) and to discuss using of quantitative methods in HRM. Firstly, five variables establish HRM theory. They are HRM practices, positi... Research topic of this paper is to discuss theory of Human Resources Management (HRM) and to discuss using of quantitative methods in HRM. Firstly, five variables establish HRM theory. They are HRM practices, positive organizational behaviors, individual performance, performance of business departments, and firm performance. Transactions among those variables enable Human Resources (HR) practitioners to apply HRM theory in their organizations. Secondly, this paper discusses use of quantitative methods in HRM. They are vector analysis and decision tree analysis. Those analyses enable HR practitioners to make effective HR decisions. Decision tree sets HR alternatives to efficiently implement HRM practices in organizations. Research question is how HR practitioners apply quantitative methods in department of HRM in firms. Finally this research comes out a conclusion that quantitative methods may be used in HRM. 展开更多
关键词 Human Resources Management (HRM) theory VECTORS matrice decision tree quantitative method
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Electro-spark epitaxial deposition of NiCoCrAlYTa alloy on directionally solidified nickel-based superalloy 被引量:6
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作者 王茂才 王维夫 +1 位作者 谢玉江 张杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期795-802,共8页
An 8 mm-high NiCoCrAlYTa coating was epitaxially built-up on a directionally solidified (DS) Ni-based superalloy blade tip by electro-spark deposition.Epitaxial morphologies of the coating and its microstructural char... An 8 mm-high NiCoCrAlYTa coating was epitaxially built-up on a directionally solidified (DS) Ni-based superalloy blade tip by electro-spark deposition.Epitaxial morphologies of the coating and its microstructural characteristics were investigated by means of SEM,XRD and TEM etc.It is observed that the fine column-like dendrites originated from the γ'-particles or γ'-clusters of the DS substrate and are un-continuously coarsened.The β-phase particles precipitate and grow eutectically with the γ-phase.The orientation of fine column dendrites depends on electro-spark deposition processing parameters and the microstructure can be characterized with superfine γ and β phases. 展开更多
关键词 electro-spark deposition epitaxial growth MCrAlY alloy Ni-base superalloy
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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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Solutions of the Schrdinger Equation for PT-Symmetric Coupled Quintic Potentials in Two Dimensions
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作者 Savita Fakir Chand 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第9期419-422,共4页
This paper deals with the solutions of time independent Schrodinger wave equation for a two-dimensional PT-symmetric coupled quintic potential in its most general form. Employing wavefunction ansatz method, general an... This paper deals with the solutions of time independent Schrodinger wave equation for a two-dimensional PT-symmetric coupled quintic potential in its most general form. Employing wavefunction ansatz method, general analytic expressions for eigenvalues and eigenfunctions for first four states are obtained. Solutions of a particular case are also presented. 展开更多
关键词 Schrodinger equation quintic potential PT-syrametry EIGENVALUE EIGENFUNCTION
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Effects of nitrogen specification and culture method on growth of Enteromorpha prolifera 被引量:3
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作者 李俭平 赵卫红 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期874-882,共9页
Eutrophication, which is the enrichment of a water mass with inorganic and organic nutrients that support plant growth, is a key factor in stimulating phytoplankton growth. In this study, we determined the effects of ... Eutrophication, which is the enrichment of a water mass with inorganic and organic nutrients that support plant growth, is a key factor in stimulating phytoplankton growth. In this study, we determined the effects of various nitrogen sources, different nitrogen concentrations in the culture medium, and two culture methods on the growth of the green alga, Enteromorpha prolifera. The relationship between the specific growth rate of E. prolifera and NO3-N concentration was consistent with that estimated using the Monod equation (R2=0.9713, P〈0.01). In the N O3-N medium, the maximum specific growth rate was calculated to be 0.1634/d and the semi-saturation constant was calculated to be 16.86 μmol/L. Our results show that E. prolijkra can effectively utilize NH4^+-N, NO3^-N, and NO^2-N and urea-N in the range of 5 to 50 μmol/L. NH4^+-N was preferentially assimilated by E. prolifera, and urea-N was favorable for long-term growth. 展开更多
关键词 EUTROPHICATION N concentrations N sources culture methods E. prolifera
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