**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**342

# Search results for: inverse problems

##### 342 A Multigrid Approach for Three-Dimensional Inverse Heat Conduction Problems

**Authors:**
Jianhua Zhou,
Yuwen Zhang

**Abstract:**

A two-step multigrid approach is proposed to solve the inverse heat conduction problem in a 3-D object under laser irradiation. In the first step, the location of the laser center is estimated using a coarse and uniform grid system. In the second step, the front-surface temperature is recovered in good accuracy using a multiple grid system in which fine mesh is used at laser spot center to capture the drastic temperature rise in this region but coarse mesh is employed in the peripheral region to reduce the total number of sensors required. The effectiveness of the two-step approach and the multiple grid system are demonstrated by the illustrative inverse solutions. If the measurement data for the temperature and heat flux on the back surface do not contain random error, the proposed multigrid approach can yield more accurate inverse solutions. When the back-surface measurement data contain random noise, accurate inverse solutions cannot be obtained if both temperature and heat flux are measured on the back surface.

**Keywords:**
Conduction,
inverse problems,
conjugated gradient method,
laser.

##### 341 Uncontrollable Inaccuracy in Inverse Problems

**Authors:**
Yu. Menshikov

**Abstract:**

In this paper the influence of errors of function derivatives in initial time which have been obtained by experiment (uncontrollable inaccuracy) to the results of inverse problem solution was investigated. It was shown that these errors distort the inverse problem solution as a rule near the beginning of interval where the solutions are analyzed. Several methods for removing the influence of uncontrollable inaccuracy have been suggested.

**Keywords:**
Inverse problems,
uncontrollable inaccuracy,
filtration.

##### 340 On a Class of Inverse Problems for Degenerate Differential Equations

**Authors:**
Fadi Awawdeh,
H.M. Jaradat

**Abstract:**

**Keywords:**
Inverse Problem,
Degenerate Differential Equations,
Perturbation Theory for Linear Operators

##### 339 Generalized Inverse Eigenvalue Problems for Symmetric Arrow-head Matrices

**Authors:**
Yongxin Yuan

**Abstract:**

In this paper, we first give the representation of the general solution of the following inverse eigenvalue problem (IEP): Given X ∈ Rn×p and a diagonal matrix Λ ∈ Rp×p, find nontrivial real-valued symmetric arrow-head matrices A and B such that AXΛ = BX. We then consider an optimal approximation problem: Given real-valued symmetric arrow-head matrices A, ˜ B˜ ∈ Rn×n, find (A, ˆ Bˆ) ∈ SE such that Aˆ − A˜2 + Bˆ − B˜2 = min(A,B)∈SE (A−A˜2 +B −B˜2), where SE is the solution set of IEP. We show that the optimal approximation solution (A, ˆ Bˆ) is unique and derive an explicit formula for it.

**Keywords:**
Partially prescribed spectral information,
symmetric arrow-head matrix,
inverse problem,
optimal approximation.

##### 338 A New Analytical Approach to Reconstruct Residual Stresses Due to Turning Process

**Authors:**
G.H. Farrahi,
S.A. Faghidian,
D.J. Smith

**Abstract:**

**Keywords:**
Residual stress,
Limited measurements,
Inverse
problems,
Turning process.

##### 337 On a New Inverse Polynomial Numerical Scheme for the Solution of Initial Value Problems in Ordinary Differential Equations

**Authors:**
R. B. Ogunrinde

**Abstract:**

**Keywords:**
Differential equations,
Numerical,
Initial value
problem,
Polynomials.

##### 336 Development of a Neural Network based Algorithm for Multi-Scale Roughness Parameters and Soil Moisture Retrieval

**Authors:**
L. Bennaceur Farah,
I. R. Farah,
R. Bennaceur,
Z. Belhadj,
M. R. Boussema

**Abstract:**

**Keywords:**
Remote sensing,
rough surfaces,
inverse problems,
SAR,
radar scattering,
Neural networks and Fractals.

##### 335 Inverse Heat Conduction Analysis of Cooling on Run Out Tables

**Authors:**
M. S. Gadala,
Khaled Ahmed,
Elasadig Mahdi

**Abstract:**

In this paper, we introduced a gradient-based inverse solver to obtain the missing boundary conditions based on the readings of internal thermocouples. The results show that the method is very sensitive to measurement errors, and becomes unstable when small time steps are used. The artificial neural networks are shown to be capable of capturing the whole thermal history on the run-out table, but are not very effective in restoring the detailed behavior of the boundary conditions. Also, they behave poorly in nonlinear cases and where the boundary condition profile is different. GA and PSO are more effective in finding a detailed representation of the time-varying boundary conditions, as well as in nonlinear cases. However, their convergence takes longer. A variation of the basic PSO, called CRPSO, showed the best performance among the three versions. Also, PSO proved to be effective in handling noisy data, especially when its performance parameters were tuned. An increase in the self-confidence parameter was also found to be effective, as it increased the global search capabilities of the algorithm. RPSO was the most effective variation in dealing with noise, closely followed by CRPSO. The latter variation is recommended for inverse heat conduction problems, as it combines the efficiency and effectiveness required by these problems.

**Keywords:**
Inverse Analysis,
Function Specification,
Neural Net
Works,
Particle Swarm,
Run Out Table.

##### 334 Application of Adaptive Neural Network Algorithms for Determination of Salt Composition of Waters Using Laser Spectroscopy

**Authors:**
Tatiana A. Dolenko,
Sergey A. Burikov,
Alexander O. Efitorov,
Sergey A. Dolenko

**Abstract:**

In this study, a comparative analysis of the approaches associated with the use of neural network algorithms for effective solution of a complex inverse problem – the problem of identifying and determining the individual concentrations of inorganic salts in multicomponent aqueous solutions by the spectra of Raman scattering of light – is performed. It is shown that application of artificial neural networks provides the average accuracy of determination of concentration of each salt no worse than 0.025 M. The results of comparative analysis of input data compression methods are presented. It is demonstrated that use of uniform aggregation of input features allows decreasing the error of determination of individual concentrations of components by 16-18% on the average.

**Keywords:**
Inverse problems,
multi-component solutions,
neural
networks,
Raman spectroscopy.

##### 333 Statistical Analysis for Overdispersed Medical Count Data

**Authors:**
Y. N. Phang,
E. F. Loh

**Abstract:**

Many researchers have suggested the use of zero inflated Poisson (ZIP) and zero inflated negative binomial (ZINB) models in modeling overdispersed medical count data with extra variations caused by extra zeros and unobserved heterogeneity. The studies indicate that ZIP and ZINB always provide better fit than using the normal Poisson and negative binomial models in modeling overdispersed medical count data. In this study, we proposed the use of Zero Inflated Inverse Trinomial (ZIIT), Zero Inflated Poisson Inverse Gaussian (ZIPIG) and zero inflated strict arcsine models in modeling overdispered medical count data. These proposed models are not widely used by many researchers especially in the medical field. The results show that these three suggested models can serve as alternative models in modeling overdispersed medical count data. This is supported by the application of these suggested models to a real life medical data set. Inverse trinomial, Poisson inverse Gaussian and strict arcsine are discrete distributions with cubic variance function of mean. Therefore, ZIIT, ZIPIG and ZISA are able to accommodate data with excess zeros and very heavy tailed. They are recommended to be used in modeling overdispersed medical count data when ZIP and ZINB are inadequate.

**Keywords:**
Zero inflated,
inverse trinomial distribution,
Poisson inverse Gaussian distribution,
strict arcsine distribution,
Pearson’s goodness of fit.

##### 332 The Inverse Problem of Nonsymmetric Matrices with a Submatrix Constraint and its Approximation

**Authors:**
Yongxin Yuan,
Hao Liu

**Abstract:**

In this paper, we first give the representation of the general solution of the following least-squares problem (LSP): Given matrices X ∈ Rn×p, B ∈ Rp×p and A0 ∈ Rr×r, find a matrix A ∈ Rn×n such that XT AX − B = min, s. t. A([1, r]) = A0, where A([1, r]) is the r×r leading principal submatrix of the matrix A. We then consider a best approximation problem: given an n × n matrix A˜ with A˜([1, r]) = A0, find Aˆ ∈ SE such that A˜ − Aˆ = minA∈SE A˜ − A, where SE is the solution set of LSP. We show that the best approximation solution Aˆ is unique and derive an explicit formula for it. Keyw

**Keywords:**
Inverse problem,
Least-squares solution,
model updating,
Singular value decomposition (SVD),
Optimal approximation.

##### 331 Hierarchically Modeling Cognition and Behavioral Problems of an Under-Represented Group

**Authors:**
Zhidong Zhang,
Zhi-Chao Zhang

**Abstract:**

**Keywords:**
Behavioral problems,
anxious/depression problems,
empirical-based assessment,
hierarchical modeling.

##### 330 Loudspeaker Parameters Inverse Problem for Improving Sound Frequency Response Simulation

**Authors:**
Y. T. Tsai,
Jin H. Huang

**Abstract:**

The sound pressure level (SPL) of the moving-coil loudspeaker (MCL) is often simulated and analyzed using the lumped parameter model. However, the SPL of a MCL cannot be simulated precisely in the high frequency region, because the value of cone effective area is changed due to the geometry variation in different mode shapes, it is also related to affect the acoustic radiation mass and resistance. Herein, the paper presents the inverse method which has a high ability to measure the value of cone effective area in various frequency points, also can estimate the MCL electroacoustic parameters simultaneously. The proposed inverse method comprises the direct problem, adjoint problem, and sensitivity problem in collaboration with nonlinear conjugate gradient method. Estimated values from the inverse method are validated experimentally which compared with the measured SPL curve result. Results presented in this paper not only improve the accuracy of lumped parameter model but also provide the valuable information on loudspeaker cone design.

**Keywords:**
Inverse problem,
cone effective area,
loudspeaker,
nonlinear conjugate gradient method.

##### 329 Inverse Matrix in the Theory of Dynamic Systems

**Authors:**
R. Masarova,
M. Juhas,
B. Juhasova,
Z. Sutova

**Abstract:**

**Keywords:**
Dynamic system,
transfer matrix,
inverse matrix,
modeling.

##### 328 A Survey of Discrete Facility Location Problems

**Authors:**
Z. Ulukan,
E. Demircioğlu

**Abstract:**

**Keywords:**
Discrete location problems,
exact methods,
heuristic
algorithms,
single source capacitated facility location problems.

##### 327 Minimization Problems for Generalized Reflexive and Generalized Anti-Reflexive Matrices

**Authors:**
Yongxin Yuan

**Abstract:**

Let R ∈ Cm×m and S ∈ Cn×n be nontrivial unitary involutions, i.e., RH = R = R−1 = ±Im and SH = S = S−1 = ±In. A ∈ Cm×n is said to be a generalized reflexive (anti-reflexive) matrix if RAS = A (RAS = −A). Let ρ be the set of m × n generalized reflexive (anti-reflexive) matrices. Given X ∈ Cn×p, Z ∈ Cm×p, Y ∈ Cm×q and W ∈ Cn×q, we characterize the matrices A in ρ that minimize AX−Z2+Y HA−WH2, and, given an arbitrary A˜ ∈ Cm×n, we find a unique matrix among the minimizers of AX − Z2 + Y HA − WH2 in ρ that minimizes A − A˜. We also obtain sufficient and necessary conditions for existence of A ∈ ρ such that AX = Z, Y HA = WH, and characterize the set of all such matrices A if the conditions are satisfied. These results are applied to solve a class of left and right inverse eigenproblems for generalized reflexive (anti-reflexive) matrices.

**Keywords:**
approximation,
generalized reflexive matrix,
generalized
anti-reflexive matrix,
inverse eigenvalue problem.

##### 326 An Inverse Optimal Control Approach for the Nonlinear System Design Using ANN

**Authors:**
M. P. Nanda Kumar,
K. Dheeraj

**Abstract:**

The design of a feedback controller, so as to minimize a given performance criterion, for a general non-linear dynamical system is difficult; if not impossible. But for a large class of non-linear dynamical systems, the open loop control that minimizes a performance criterion can be obtained using calculus of variations and Pontryagin’s minimum principle. In this paper, the open loop optimal trajectories, that minimizes a given performance measure, is used to train the neural network whose inputs are state variables of non-linear dynamical systems and the open loop optimal control as the desired output. This trained neural network is used as the feedback controller. In other words, attempts are made here to solve the “inverse optimal control problem” by using the state and control trajectories that are optimal in an open loop sense.

**Keywords:**
Inverse Optimal Control,
Radial basis function neural network,
Controller Design.

##### 325 Inverse Problem Methodology for the Measurement of the Electromagnetic Parameters Using MLP Neural Network

**Authors:**
T. Hacib,
M. R. Mekideche,
N. Ferkha

**Abstract:**

**Keywords:**
Inverse problem,
MLP neural network,
parametersidentification,
FEM.

##### 324 The Inverse Eigenvalue Problem via Orthogonal Matrices

**Authors:**
A. M. Nazari,
B. Sepehrian,
M. Jabari

**Abstract:**

In this paper we study the inverse eigenvalue problem for symmetric special matrices and introduce sufficient conditions for obtaining nonnegative matrices. We get the HROU algorithm from [1] and introduce some extension of this algorithm. If we have some eigenvectors and associated eigenvalues of a matrix, then by this extension we can find the symmetric matrix that its eigenvalue and eigenvectors are given. At last we study the special cases and get some remarkable results.

**Keywords:**
Householder matrix,
nonnegative matrix,
Inverse eigenvalue problem.

##### 323 A Parametric Study of an Inverse Electrostatics Problem (IESP) Using Simulated Annealing, Hooke & Jeeves and Sequential Quadratic Programming in Conjunction with Finite Element and Boundary Element Methods

**Authors:**
Ioannis N. Koukoulis,
Clio G. Vossou,
Christopher G. Provatidis

**Abstract:**

The aim of the current work is to present a comparison among three popular optimization methods in the inverse elastostatics problem (IESP) of flaw detection within a solid. In more details, the performance of a simulated annealing, a Hooke & Jeeves and a sequential quadratic programming algorithm was studied in the test case of one circular flaw in a plate solved by both the boundary element (BEM) and the finite element method (FEM). The proposed optimization methods use a cost function that utilizes the displacements of the static response. The methods were ranked according to the required number of iterations to converge and to their ability to locate the global optimum. Hence, a clear impression regarding the performance of the aforementioned algorithms in flaw identification problems was obtained. Furthermore, the coupling of BEM or FEM with these optimization methods was investigated in order to track differences in their performance.

**Keywords:**
Elastostatic,
inverse problem,
optimization.

##### 322 Numerical Simulations of Acoustic Imaging in Hydrodynamic Tunnel with Model Adaptation and Boundary Layer Noise Reduction

**Authors:**
Sylvain Amailland,
Jean-Hugh Thomas,
Charles Pézerat,
Romuald Boucheron,
Jean-Claude Pascal

**Abstract:**

**Keywords:**
Acoustic imaging,
boundary layer noise denoising,
inverse problems,
model adaptation.

##### 321 Comparison Results of Two-point Fuzzy Boundary Value Problems

**Authors:**
Hsuan-Ku Liu

**Abstract:**

This paper investigates the solutions of two-point fuzzy boundary value problems as the form x = f(t, x(t)), x(0) = A and x(l) = B, where A and B are fuzzy numbers. There are four different solutions for the problems when the lateral type of H-derivative is employed to solve the problems. As f(t, x) is a monotone function of x, these four solutions are reduced to two different solutions. As f(t, x(t)) = λx(t) or f(t, x(t)) = -λx(t), solutions and several comparison results are presented to indicate advantages of each solution.

**Keywords:**
Fuzzy derivative,
lateral type of H-derivative,
fuzzy differential equations,
fuzzy boundary value problems,
boundary value problems.

##### 320 An Iterative Algorithm to Compute the Generalized Inverse A(2) T,S Under the Restricted Inner Product

**Authors:**
Xingping Sheng

**Abstract:**

**Keywords:**
Generalized inverse A(2)
T,
S,
Restricted inner product,
Iterative method,
Orthogonal projection.

##### 319 Solving Definition and Relation Problems in English Navigation Terminology

**Authors:**
Ayşe Yurdakul,
Eckehard Schnieder

**Abstract:**

Because of the increasing multidisciplinarity and multilinguality, communication problems in different technical fields grow more and more. Therefore, each technical field has its own specific language, terminology which is characterized by the different definition of terms. In addition to definition problems, there are also relation problems between terms. Among these problems of relation, there are the synonymy, antonymy, hypernymy/hyponymy, ambiguity, risk of confusion and translation problems etc.

Thus, the* *terminology management system *iglos *of the Institute for Traffic Safety and Automation Engineering of the Technische Universität Braunschweig has the target to solve these problems by a methodological standardisation of term definitions with the aid of the* iglos* sign model and *iglos* relation types. The focus of this paper should be on solving definition and relation problems between terms in English navigation terminology.

**Keywords:**
Iglos,
iglos sign model,
methodological resolutions,
navigation terminology,
common language,
technical language,
positioning,
definition problems,
relation problems.

##### 318 Topological Sensitivity Analysis for Reconstruction of the Inverse Source Problem from Boundary Measurement

**Authors:**
Maatoug Hassine,
Mourad Hrizi

**Abstract:**

**Keywords:**
Geometric inverse source problem,
heat equation,
topological sensitivity,
topological optimization,
Kohn-Vogelius
formulation.

##### 317 Artificial Neural Network with Steepest Descent Backpropagation Training Algorithm for Modeling Inverse Kinematics of Manipulator

**Authors:**
Thiang,
Handry Khoswanto,
Rendy Pangaldus

**Abstract:**

Inverse kinematics analysis plays an important role in developing a robot manipulator. But it is not too easy to derive the inverse kinematic equation of a robot manipulator especially robot manipulator which has numerous degree of freedom. This paper describes an application of Artificial Neural Network for modeling the inverse kinematics equation of a robot manipulator. In this case, the robot has three degree of freedoms and the robot was implemented for drilling a printed circuit board. The artificial neural network architecture used for modeling is a multilayer perceptron networks with steepest descent backpropagation training algorithm. The designed artificial neural network has 2 inputs, 2 outputs and varies in number of hidden layer. Experiments were done in variation of number of hidden layer and learning rate. Experimental results show that the best architecture of artificial neural network used for modeling inverse kinematics of is multilayer perceptron with 1 hidden layer and 38 neurons per hidden layer. This network resulted a RMSE value of 0.01474.

**Keywords:**
Artificial neural network,
back propagation,
inverse kinematics,
manipulator,
robot.

##### 316 Recovering the Boundary Data in the Two Dimensional Inverse Heat Conduction Problem Using the Ritz-Galerkin Method

**Authors:**
Saeed Sarabadan,
Kamal Rashedi

**Abstract:**

**Keywords:**
Inverse problem,
parabolic equations,
heat equation,
Ritz-Galerkin method,
Landweber iterations.

##### 315 An Extension of the Kratzel Function and Associated Inverse Gaussian Probability Distribution Occurring in Reliability Theory

**Authors:**
R. K. Saxena,
Ravi Saxena

**Abstract:**

In view of their importance and usefulness in reliability theory and probability distributions, several generalizations of the inverse Gaussian distribution and the Krtzel function are investigated in recent years. This has motivated the authors to introduce and study a new generalization of the inverse Gaussian distribution and the Krtzel function associated with a product of a Bessel function of the third kind )(zKQ and a Z - Fox-Wright generalized hyper geometric function introduced in this paper. The introduced function turns out to be a unified gamma-type function. Its incomplete forms are also discussed. Several properties of this gamma-type function are obtained. By means of this generalized function, we introduce a generalization of inverse Gaussian distribution, which is useful in reliability analysis, diffusion processes, and radio techniques etc. The inverse Gaussian distribution thus introduced also provides a generalization of the Krtzel function. Some basic statistical functions associated with this probability density function, such as moments, the Mellin transform, the moment generating function, the hazard rate function, and the mean residue life function are also obtained.KeywordsFox-Wright function, Inverse Gaussian distribution, Krtzel function & Bessel function of the third kind.

**Keywords:**
Fox-Wright function,
Inverse Gaussian distribution,
Krtzel function & Bessel function of the third kind.

##### 314 Prediction of the Thermal Parameters of a High-Temperature Metallurgical Reactor Using Inverse Heat Transfer

**Authors:**
Mohamed Hafid,
Marcel Lacroix

**Abstract:**

This study presents an inverse analysis for predicting the thermal conductivities and the heat flux of a high-temperature metallurgical reactor simultaneously. Once these thermal parameters are predicted, the time-varying thickness of the protective phase-change bank that covers the inside surface of the brick walls of a metallurgical reactor can be calculated. The enthalpy method is used to solve the melting/solidification process of the protective bank. The inverse model rests on the Levenberg-Marquardt Method (LMM) combined with the Broyden method (BM). A statistical analysis for the thermal parameter estimation is carried out. The effect of the position of the temperature sensors, total number of measurements and measurement noise on the accuracy of inverse predictions is investigated. Recommendations are made concerning the location of temperature sensors.

**Keywords:**
Inverse heat transfer,
phase change,
metallurgical reactor,
Levenberg–Marquardt method,
Broyden method,
bank thickness.

##### 313 Open Problems on Zeros of Analytic Functions in Finite Quantum Systems

**Authors:**
Muna Tabuni

**Abstract:**

The paper contains an investigation on basic problems about the zeros of analytic theta functions. A brief introduction to analytic representation of finite quantum systems is given. The zeros of this function and there evolution time are discussed. Two open problems are introduced. The first problem discusses the cases when the zeros follow the same path. As the basis change the quantum state |f transforms into different quantum state. The second problem is to define a map between two toruses where the domain and the range of this map are the analytic functions on toruses.

**Keywords:**
open problems,
constraint,
change of basis.