A least square procedure for the solution of Pocklington's equation

The paper deals with the application of the so-called T-type finite elements [1] to the calculation of the exterior acoustic problems in two dimensions. The method is based on the use of asuitably truncated T-complete set of Trefftz functions over individual subdomains linked by means ofa least square procedure. The vertex singularities and the Sommerfeld radiation condition are readilyincorporated in the trial functions. In order to show the performance of the approach two examples ofcomputations for infinite cylinders (of circular and square cross section) are presented and comparedwith those obtained by means of h-adaptive FE method [2].

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Modelling of Cyclic Plasticity and Viscoplasticity of Directionally Solified DZ125 Superalloy: Part I: Estimating the Parameters of Chaboche Constitutive Equations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.854 ◽

2011 ◽

Vol 295-297 ◽

pp. 854-858

Author(s):

Jie Qiong Li ◽

Li Jun Wang

Keyword(s):

Constitutive Model ◽

Test Data ◽

Creep Test ◽

Constitutive Equations ◽

Least Square ◽

Cyclic Plasticity ◽

Initial Material ◽

Material Parameters ◽

Cyclic Relaxation ◽

Least Square Procedure

Cyclic plasticity and viscoplasticity of directionally solified superalloy, DZ125, have been described using the Chaboche uniﬁed constitutive model. A set of initial material parameters has been determined utilizing the monotonic, cyclic, relaxation and creep test data of DZ125 at 980°C, while an optimum set of material parameters has been obtained by means of least-square procedure.

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Adsorption of amyloglucosidase from Aspergillus niger NRRL 3122 using ion exchange resin

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132008000500019 ◽

2008 ◽

Vol 51 (5) ◽

pp. 1015-1024 ◽

Cited By ~ 3

Author(s):

Ana Paula Manera ◽

Eliana Setsuko Kamimura ◽

Luciana Machado Brites ◽

Susana Juliano Kalil

Keyword(s):

Aspergillus Niger ◽

Partition Coefficient ◽

Partition Coefficients ◽

Deae Cellulose ◽

Ion Exchange Resin ◽

Least Square ◽

Optimum Conditions ◽

Equilibrium Partition ◽

Equilibrium Partition Coefficient ◽

Least Square Procedure

Amyloglucosidase enzyme was produced by Aspergillus niger NRRL 3122 from solid-state fermentation, using deffated rice bran as substrate. The effects of process parameters (pH, temperature) in the equilibrium partition coefficient for the system amyloglucosidase - resin DEAE-cellulose were investigated, aiming at obtaining the optimum conditions for a subsequent purification process. The highest partition coefficients were obtained using 0.025M Tris-HCl buffer, pH 8.0 and 25ºC. The conditions that supplied the highest partition coefficient were specified, the isotherm that better described the amyloglucosidase process of adsorption obtained. It was observed that the adsorption could be well described by Langmuir equation and the values of Qm and Kd estimated at 133.0 U mL-1 and 15.4 U mL-1, respectively. From the adjustment of the kinetic curves using the fourth-order Runge-Kutta algorithm, the adsorption (k1) and desorption (k2) constants were obtained through optimization by the least square procedure, and the values calculated were 2.4x10-3 mL U-1 min-1 for k1 and 0.037 min-1 for k2 .

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Smoothing and differentiation of data by simplified least square procedure

Analytical Chemistry ◽

10.1021/ac60319a045 ◽

1972 ◽

Vol 44 (11) ◽

pp. 1906-1909 ◽

Cited By ~ 666

Author(s):

Jean. Steinier ◽

Yves. Termonia ◽

Jules. Deltour

Keyword(s):

Least Square ◽

Least Square Procedure

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Examining the Significance of the Luzon W-growth Corridor to Agricultural Agglomeration and Labor Productivity

Millennium Journal of Humanities and Social Sciences ◽

10.47340/mjhss.v1i3.1.2020 ◽

2020 ◽

pp. 1-16

Author(s):

Marie Antoinette Lukban Rosete ◽

Nancy L. Eleria

Keyword(s):

Labor Productivity ◽

Regional Growth ◽

Access Network ◽

The Philippines ◽

Least Square ◽

Annual Data ◽

Structural Form ◽

Endogeneity Bias ◽

Agriculture Labor ◽

Least Square Procedure

Abstract Economic corridors are transport routes that form a strategic access network for economic hubs to reinforce regional growth. Transport corridors ensure the decisive movement of people and goods. The Philippines made its initial corridor development efforts aimed at prioritizing local industries and trade activity within its geographical confines. The W-Growth corridor (LWGC) on the island of Luzon passes through the provinces in Central Luzon and extends to the CALABARZON region. This research established the significance of the institutionalization of LWGC on agricultural agglomeration and labor productivity by applying particular measurements for corridor utilization and effects. Annual data on production sectors per region were utilized for corridor monitoring and agriculture productivity were utilized for corridor evaluation. The structural form of the proposed economic models apprised endogeneity bias, so the Two-Stage Least Square procedure was applied. This procedure revealed non-incidence of regional agriculture agglomeration, but that competition for agriculture labor is evident. Trade activity was also found to boost both output and labor productivity in agriculture. Keywords: transport corridor, institutionalization, agglomeration, labor productivity in agriculture

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Analytical representation for ephemeride with short time spans

Astronomy and Astrophysics ◽

10.1051/0004-6361/201937148 ◽

2020 ◽

Vol 635 ◽

pp. A91

Author(s):

X. J. Xi ◽

A. Vienne

Keyword(s):

Numerical Integration ◽

Least Square ◽

Analytical Representation ◽

Good Precision ◽

Orbital Elements ◽

The Mean ◽

Natural Satellites ◽

Almost All ◽

Short Time ◽

Least Square Procedure

Context. The ephemerides of natural satellites resulting from numerical integration have a very good precision on the fitting to recent observations, in a limited interval. Meanwhile, synthetic ephemerides like the Théorie Analytique des Satellites de Saturne (TASS) by Vienne and Duriez describe in detail the dynamical system by a representation based on the combinations of the proper frequencies. Some theoretical studies need to have both advantages. For example, to study the rotation of Titan, one needs to know the representation of its longitude. Aims. We aim to use these two types of ephemerides in order to rebuild a long-lasting and high-precision ephemeris with proper frequencies based on the numerical integration ephemeris. The aim is to describe the numerical ephemerides with formulas similar to analytical ones. Methods. We used the representation of the orbital elements from the TASS ephemeris analysed over 10 000 years as a reference template. We obtained the proper frequencies with both numerical and the TASS ephemeris over 1000 years only. A least-square procedure allowed us to get the analytical representation of an orbital element in this limited interval. Results. We acquire the representation of the mean longitude of Titan from JPL ephemeris over 1000 years. For almost all components, the corresponding amplitudes and phases are similar to the relative terms from TASS. The biggest difference between our representation and the mean longitude of Titan of JPL is less than 100 km over 1000 years, and the standard deviation is about 26 km.

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