Am. J. Comput. Math.最新文献

Conditional Value-at-Risk for Random Immediate Reward Variables in Markov Decision Processes 马尔可夫决策过程中随机即时奖励变量的条件风险值

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13021

Masayuki Kageyama, Takayuki Fujii, K. Kanefuji, H. Tsubaki

引用次数: 3

Quasi-Reversibility Regularization Method for Solving a Backward Heat Conduction Problem 求解逆向热传导问题的拟可逆正则化方法

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13018

Ailin Qian, Jian-feng Mao

引用次数: 5

Haar Wavelet Quasilinearization Approach for Solving Nonlinear Boundary Value Problems 求解非线性边值问题的Haar小波拟线性化方法

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13020

Harpreet Kaur, R. C. Mittal, Vinod Mishra

引用次数: 33

Simulation of Human Phonation with Vocal Nodules 用声带结节模拟人类发声

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13022

S. Deguchi, Yukihito Kawahara

{"title":"Simulation of Human Phonation with Vocal Nodules","authors":"S. Deguchi, Yukihito Kawahara","doi":"10.4236/ajcm.2011.13022","DOIUrl":"https://doi.org/10.4236/ajcm.2011.13022","url":null,"abstract":"The geometric and biomechanical properties of the larynx strongly influence voice quality and efficiency. A physical understanding of phonation natures in pathological conditions is important for predictions of how voice disorders can be treated using therapy and rehabilitation. Here, we present a continuum-based numerical model of phonation that considers complex fluid-structure interactions occurring in the airway. This model considers a three-dimensional geometry of vocal folds, muscle contractions, and viscoelastic properties to provide a realistic framework of phonation. The vocal fold motion is coupled to an unsteady compressible respiratory flow, allowing numerical simulations of normal and diseased phonations to derive clear relationships between actual laryngeal structures and model parameters such as muscle activity. As a pilot analysis of diseased phonation, we model vocal nodules, the mass lesions that can appear bilaterally on both sides of the vocal folds. Comparison of simulations with and without the nodules demonstrates how the lesions affect vocal fold motion, consequently restricting voice quality. Furthermore, we found that the minimum lung pressure required for voice production increases as nodules move closer to the center of the vocal fold. Thus, simulations using the developed model may provide essential insight into complex phonation phenomena and further elucidate the etiologic mechanisms of voice disorders.","PeriodicalId":359476,"journal":{"name":"Am. J. Comput. Math.","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116959579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

A Fourth Order Improved Numerical Scheme for the Generalized Burgers - Huxley Equation 广义Burgers - Huxley方程的一种四阶改进数值格式

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13017

A. G. Bratsos

引用次数: 41

Operator Splitting Method for Coupled Problems: Transport and Maxwell Equations 耦合问题的算子分裂方法:输运和麦克斯韦方程

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13019

J. Geiser

引用次数: 3

Computing the Moore-Penrose Inverse of a Matrix Through Symmetric Rank-One Updates 通过对称秩一更新计算矩阵的Moore-Penrose逆

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13016

Xuzhou Chen, J. Ji

引用次数: 14

Computational Optimization of Manufacturing Batch Size and Shipment for an Integrated EPQ Model with Scrap 含废料集成EPQ模型的生产批量和出货的计算优化

Am. J. Comput. Math. Pub Date : 2011-09-19 DOI: 10.4236/ajcm.2011.13023

Y. Chiu, Hong-Dar Lin, M. Hwang, N. Pan

引用次数: 7

Numerical Solution of Nonlinear Fredholm-Volterra Integtral Equations via Piecewise Constant Function by Collocation Method 非线性Fredholm-Volterra积分方程的分段常函数配点法数值解

Am. J. Comput. Math. Pub Date : 2011-06-30 DOI: 10.4236/ajcm.2011.12014

A. Shahsavaran

引用次数: 7

Methods of Approximation in hpk Framework for ODEs in Time Resulting from Decoupling of Space and Time in IVPs 在hpk框架下求解ivp中时空解耦的时间ode的逼近方法

Am. J. Comput. Math. Pub Date : 2011-06-30 DOI: 10.4236/ajcm.2011.12009

K. Surana, L. Euler, J. Reddy, A. Romkes

{"title":"Methods of Approximation in hpk Framework for ODEs in Time Resulting from Decoupling of Space and Time in IVPs","authors":"K. Surana, L. Euler, J. Reddy, A. Romkes","doi":"10.4236/ajcm.2011.12009","DOIUrl":"https://doi.org/10.4236/ajcm.2011.12009","url":null,"abstract":"The present study considers mathematical classification of the time differential operators and then applies methods of approximation in time such as Galerkin method ( GM ), Galerkin method with weak form ( / GM WF ), Petrov-Galerkin method ( PGM ), weighted residual method (WRY ), and least squares method or process ( LSM or LSP ) to construct finite element approximations in time. A correspondence is established between these integral forms and the elements of the calculus of variations: 1) to determine which methods of approximation yield unconditionally stable (variationally consistent integral forms, VC ) computational processes for which types of operators and, 2) to establish which integral forms do not yield unconditionally stable computations (variationally inconsistent integral forms, VIC ). It is shown that variationally consistent time integral forms in hpk framework yield computational processes for ODEs in time that are unconditionally stable, provide a mechanism of higher order global differentiability approximations as well as higher degree local approximations in time, provide control over approximation error when used as a time marching process and can indeed yield time accurate solutions of the evolution. Numerical studies are presented using standard model problems from the literature and the results are compared with Wilson’s  method as well as Newmark method to demonstrate highly meritorious features of the proposed methodology.","PeriodicalId":359476,"journal":{"name":"Am. J. Comput. Math.","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129434410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3