數值近似法 的英文怎麼說
中文拼音 [shǔzhíjìnsìfǎ]
數值近似法
英文
numerical approximation- 數 : 數副詞(屢次) frequently; repeatedly
- 近 : Ⅰ形容詞1 (空間或時間距離短) near; close 2 (接近) approaching; approximately; close to 3 (親...
- 法 : Ⅰ名詞1 (由國家制定或認可的行為規則的總稱) law 2 (方法; 方式) way; method; mode; means 3 (標...
- 數值 : numerical value; numerial number; figure; magnitude; value數值表 numerical tabular; 數值天氣預報 ...
- 近似 : approximate; similar; approach; approximation; roughness; propinquity
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Optimized association rules are permitted to contain uninstantiated attributes. the optimization procedure is to determine the instantiations such that some measures of the roles are maximized. this paper tries to maximize interest to find more interesting rules. on the other hand, the approach permits the optimized association rule to contain uninstantiated numeric attributes in both the antecedence and the consequence. a naive algorithm of finding such optimized rules can be got by a straightforward extension of the algorithm for only one numeric attribute. unfortunately, that results in a poor performance. a heuristic algorithm that finds the approximate optimal rules is proposed to improve the performance. the experiments with the synthetic data sets show the advantages of interest over confidence on finding interesting rules with two attributes. the experiments with real data set show the approximate linear scalability and good accuracy of the algorithm
優化關聯規則允許在規則中包含未初始化的屬性.優化過程就是確定對這些屬性進行初始化,使得某些度量最大化.最大化興趣度因子用來發現更加有趣的規則;另一方面,允許優化規則在前提和結果中各包含一個未初始化的數值屬性.對那些處理一個數值屬性的演算法進行直接的擴展,可以得到一個發現這種優化規則的簡單演算法.然而這種方法的性能很差,因此,為了改善性能,提出一種啟發式方法,它發現的是近似最優的規則.在人造數據集上的實驗結果表明,當優化規則包含兩個數值屬性時,優化興趣度因子得到的規則比優化可信度得到的規則更有趣.在真實數據集上的實驗結果表明,該演算法具有近似線性的可擴展性和較好的精度The experiments show that the performance of our method is similar to the ye - 0. 699 algorithm, which is the best approximate algorithm in polynomial time. but our method can effectively solve the max - bisection problem with a large scale. 2
數值實驗表明,該方法與ye - 0 . 699近似演算法(現有的求解圖的最大二等分問題的最好的多項式時間近似演算法)得到的解的性能幾乎沒有差異( 4 ) on the efficient method for the dynamical core of the new generation multi - scale forecasting model i ) we present a new multi - level sparse approximate inverse preconditnioner for the complicated 3 - d helmholtz equations in the new generation weather forecasting model. as a result, the new sparse approximate inverse preconditioned gcr and gmres algorithms are given and successfully applied in the dynamical core. numerical tests show that the new algorithms perform very efficiently, and can greatly improve the efficiency of numerical model
對此,本文提出了一種基於逐層門限技術的近似逆矩陣稀疏模式預選方法,並構造了相應的稀疏近似逆預條件子,結合gcr演算法和g州[ r衛s演算法,首次將逐層門限稀疏近似逆預條件子應用於新一代多尺度預報模式動力內核的實際計算,數值實驗表明這里給出的方法可以大大提高數值模式的計算效率。Numerical procedures of upper - bound approximation of shakedown loads and its application in engineering
安定荷載上限近似解的數值分析方法及其應用After coordinate transformation, we can get the approximate confidence region of parameters in virtue of the approximate expression of e
然後利用坐標變換,藉助e ~ x的近似式,用數值方法求解獲得參數的近似置信域。In order to calculate easily and do n ' t influence the single - chip microcomputer ' s calculate velocity, we put forward two scheme to deal with the numerical value, one is to use a simple function to close or approach a normal function f ( x ) ( mainly is lagrange ' s intepolation, newton ' s intepolation, hermite ' s intepolation, cubic spline interpolation, etc. ) the other one is function approach ( mainly is chebyshev ' s polynomic. legendre ' s polynomic, laguerre ' s polynomic, method of least squares, etc. ), we analyze and compare the lagrange ' s intepolation and chebyshev ploynomic, at last, we select the chebyshev polynomic to do the value calculating on single - chip microcomputer
提出了數值處理的二種方案。即用簡單函數近似或逼近一個一般函數f ( x ) (主要有拉格朗日插值、牛頓插值、埃爾米特插值、三次樣條插值等)和函數逼近(主要有切比雪夫多項式、勒讓德多項式、拉蓋爾多項式、最小二乘法等) ,對上述兩個方案中的典型函數?拉格朗日插值和切比雪夫多項式進行了分析比較,最後選取切比雪夫多項式完成單片機上的數值計算。The equation including the nonlinear dispersion, i. e. the modified nonlinear schrodinger ( mnls ) equation, is a better model. in this thesis, we take mnls solitons as a model for femtosecond soltions. then based on the recently developed direct perturbation theory for perturbed mnls equation, we study the raman self - frequency shift of femtosecond solitons and its suppression by the means of frequency filters. for this purpose, first, we define the physical parameters of mnls solitons ; next, through the direct perturbation theory for perturbed mnls equation, under adiabatic approximation, we obtain the evolving parameters of mnls soliton on our questions and then choose the parameters of frequency filters based on it ; at last, we directly numerically simulated our questions by split - step fourier ( ssf ) method after improving the arithmetic of the differentiation of the nonlinear item for satisfying mnls equation
本論文以mnls孤子作為光纖飛秒孤子的模型,通過新近建立的mnls孤子直接微擾理論,研究光纖中由拉曼效應引起的飛秒孤子在傳輸中的自頻移,以及通過頻率濾波對自頻移的抑制。為此,首先給出描述mnls孤子的各物理量,然後用mnls孤子直接微擾理論,解析地得到這些問題絕熱近似下的孤子參數演化,並由此選擇頻率濾波的參數,最後用分步傅里葉方法,在對非線性項微商的演算法做出了適合於mnls孤子的改善後,對拉曼效應及頻率濾波進行了直接數值模擬,其中頻率濾波參數用微擾理論確定。For the stress analysis of dryers under the line load of supporting rollers, according to hoff theoretical solution of thin cylindrical shell under line loads, mangelsdorf approximate solution is modified on the basis of the calculation analysis for 14 sets dryers " dimension by computer programming with matlab software. the approximate formulas of the second largest hoop stress of the middle section of the shell are derived
針對托輥線壓載荷作用下烘缸的受力分析,本文根據薄壁圓柱殼在線壓載荷作用下的hoff理論解,在運用matlab軟體對14組常用烘缸參數進行編程計算分析的基礎上,對mangelsdorf近似解作了修正,並由最小二乘法導出殼體中部截面環向應力次大值的近似計算式。From the study results it is showed that turret hole position near the forward of the midship has less effect to the ship girder strength and it is more reasonable using probabilty statistics method to estimate the extreme value of wave bending moment, by which the first approximate value of hull midship section modulus can be determined
研究結果表明:轉塔開孔位置在舯前附近對船體總強度影響不大;波浪彎矩極值用概率統計方法估算更為合理;船體結構剖面模數的第一近似值可用波浪彎矩設計極值等來確定。A new numerical algorithm integrating a quasi - analytic numerical algorithm with the gear numerical algorithm is used to solve the ordinary differential equations with stiff problem. to accelerate the solving of ode, the optimum step method is introduced into the composite numerical algorithm
針對重整反應模型方程的特殊結構和剛性問題,提出了一種形式更簡單方便的近似解析數值演算法和吉爾法相結合的混合數值演算法,並引入了最優步長方法。Thermal contact resistance is calculated by fem. the triangular model is considered more precise when its control angle equals 30 and an approximate formula is provided for calculation of the thermal contact resistance by comparing computation models
本文採用有限單元法數值計算接觸熱阻,提出控制角為30的三角形模型具有較高的精度,給出接觸熱阻的近似計算公式,並分析了表面粗糙度對接觸熱阻的影響。The discrete element method ( dem ) is a powerful tool in analyzing granular assembly. the granular discrete element method can be applied to the partials, whose shape can be approximately described as a sphere
離散元法( dem )是分析散體力學行為的數值方法,顆粒離散元法適用於單個幾何形狀可用圓球近似而不產生顯著差異的情況。An numerical algorithm of nearly arc - length parameterization
近似弧長參數化的一種數值演算法The error analysis model of sampling system was set up for the first time, by combining the saddlepoint approximation analysis and numerical arithmetic, which greatly increased the potential of further application and improved the reliability of the error approximation of the optical sampling histogram
論文首次建立了採用鞍點近似法與數值演算法相結合的取樣系統誤差分析模型,大大擴展了鞍點近似演算法的適用范圍,提高了誤碼率估算的可靠性。論文提出了基於時分取樣方法的光子模數轉換。The water quality respond relation of input - output measurements are established by systematic theory in this paper. according to the peculiarity of hydrology and the necessity of water quality inverse problem the multi - parameter inverse problem model based on ordinary differential equation is developed. the existence and uniqueness of the solution of the ordinary differential equation about two parameters or multi - parameter are to be proved. the unstability depending on errors between monitoring data and interpolation approximate data are analyzed and demonstrated. cubic spline interpolation function, the least two multiply and positive rule method are conjoined for obtained solution of multi - parameter. the results from this algorithm indicats its efficient to the multi - parameter identification in water quality modeling
本文應用系統理論,建立了水質多參數輸入輸出之間的響應關系;根據河流水文水質變化特點和參數反問題的需求,建立了水質常微分方程多參數反問題模型.根據常微分方程參數反問題的數學理論,作者給出了兩參數和多參數水質常微分方程反問題的解的存在性、唯一性的理論證明過程和結論;還針對水質現有監測資料的測驗誤差和插值近似計算誤差造成參數反問題的不穩定性,將三次樣條插值函數、超定方程最小二乘法和正則化演算法有機地結合使用,成功地給出了水質參數反問題的穩定化演算法.最後給出了應用計算結果We look at the problem of learning from examples as the problem of multivariate function approximation from sparse chosen data, and then consider the case in which the data are drawn, instead of chosen, according to a probability measure
並檢視稀疏精選值中多變量函數近似法等這些從實例學習法所發現的問題,然後根據機率衡量,審思隨機獲得資料而非選定資料的案例。In this paper, on the base of paraxial approximations, we present a set of absorbing boundary conditions of 3d elastic wave equations and apply to the 3d elastic wave numerical modeling in isotropic medium
本文基於傍軸近似法提出了計算三維彈性波方程的吸收邊界條件公式,表示了各邊界面、邊棱和角點處波場所滿足的單程波方程,並在三維彈性波數值模擬中進行了應用。Furthermore, there are complex structures such as the engine fans at the end of the inlets. it ' s hard to deal with such problems if we use high frequency method or low frequency numerical value method only
對于厘米波段雷達而言,進氣道屬于電大尺寸目標,其終端有渦輪葉片之類的復雜結構,單用高頻近似法或低頻數值法都難以解決。Consult the tolerance method of fix income security ' s market risk, we consequence and conclude the s - y approximate method of tolerance option ' s market risk base on the key theory of var parameter model, and it offer a theoretical foundation of option ' s market risk real time tolerance
參考固定收益證券的市場風險度量方法,在var (風險價值)參數模型的核心理論基礎之上,推導並歸納總結出度量期權市場風險的-近似法,為期權市場風險的實時監控提供了理論依據。In this thesis, we used the q - switched nd : yag laser pulse focused by lens to pump the cr ~ ( 4 + ) : mg _ 2sio _ 4 crystal, with the pump laser pulse duration and energy of 30ns and 50 mj separately, and got the laser pulse with center wavelength, pulse duration and energy of 1. 22 m, 8. 2 ns and 10 mj on the best work condition. on the base of zhangguowei s approximation about gain - switching and the parameter of cr ~ ( 4 + ) : mg _ 2sio _ 4 crystal, we calculated the time characteristics of cr ~ ( 4 + ) : mg _ 2sio _ 4 laser pulse with rate equation by numerical method, obtained the conclusion that the laser pulse duration is only related to the pump energy and cavity length : the larger the pump energy is, the narrower the pulse duration is ; the longer the cavity is, the wider the
本論文採用調qnd : yag脈沖激光通過透鏡聚焦后縱向抽運cr ~ ( 4 + ) : mg _ 2sio _ 4晶體,抽運光脈沖寬度為30ns 、能量為50mj ,在較佳工作條件下得到了中心波長為1 . 22 m 、脈寬為8 . 2ns 、能量為10mj的激光脈沖;並在張國威分析增益開關時間特性的近似法基礎上,結合實際的cr ~ ( 4 + ) : mg _ 2sio _ 4激光器的相關參數,從速率方程出發,用數值計算的方法更為精確的模擬了cr ~ ( 4 + ) : mg _ 2sio _ 4激光器輸出激光脈沖的時間特性,得出了激光脈寬只與抽運能量、腔長有關的結論,即抽運能量愈大,脈寬越窄;腔長越長,脈寬則愈寬。分享友人