descent n. 1.下降,降下。 2.下坡,傾斜。 3.家世,門第,血統(tǒng)。 4.【法律】繼承,世襲。 5.一代;〔古語〕子孫,后裔。 6.突然襲擊。 7.屈尊,降格。 be of France descent 祖籍是法國。 be of good descent 出身好。 descent of man 人類由來。 make a descent upon 襲擊,侵入。
Since it adopt the steepest descent method in nonlinear programming , it has the drawback that easy converge to a local minimum point of the error function 由于它采用非線性規(guī)劃中的最速下降法,因而存在極易陷入局部極小的缺陷。
Based on the steepest descent method and the conjugate gradient method , a hybrid algorithm is proposed in this paper , and its global convergence is proved 摘要將最速下降法與共扼梯度法有機(jī)結(jié)合起來,構(gòu)造出一種混合優(yōu)化算法,并證明其全局收斂性。
In the image reconstruction based on optimization without constraint , the variable metric method , the steepest descent method , and conjugate gradient method were applied to image reconstruction to improve iterative efficiency and reconstructed quality , and their virtue and shortcoming were analyzed 摘要在無約束最優(yōu)化為基礎(chǔ)的圖像重建問題中,為了提高迭代效率以及重建圖像質(zhì)量,首次提出將變度量法應(yīng)用到圖像重建中。
The hybrid algorithm raises the convergence rate of the conjugate gradient method and solves the problem for which the convergence rate of the steepest descent method get slower when the isopleth of goal function is oblong 這種混合優(yōu)化算法結(jié)合了共扼梯度法和最速下降法產(chǎn)生搜索方向,既提高了共扼梯度算法的收斂速度,又解決了目標(biāo)函數(shù)的等值線是扁長(zhǎng)橢球時(shí),最速下降法下降緩慢的問題,具有收斂速度快、收斂范圍大、適應(yīng)面廣等特點(diǎn)。
This paper researches blind equalization ruler , analyses the knowledge of hos and summarizes some algorithms based on the hos . odd - order ( third - second order and fifth - second order ) normalized cumulant algorithms are introduced and a new blind equalization ruler is proved and introduced after researching even - order normalized cumulant algorithms . then the steepest descent method is used to derive the algorithm 在分析偶數(shù)階歸一化累積量算法的基礎(chǔ)上,提出了奇數(shù)階(三、二階和五、二階)歸一化累積量算法,論證并推導(dǎo)出一種新的盲均衡準(zhǔn)則,最后利用最速下降法形成了新算法。