Artículos de Investigación en publicaciones internacionales arbitradas

Artículos de investigación en publicaciones internacionales arbitradas.

E. Pérez-Chavela, S. Rybicki, D. Strzelecki (2017) "Symmetric Liapunov Center Theorem", Calculus of Variations and Partial Differential Equations, 56, (2):26.
DOI: 10.1007/s00526-017-1120-1

Ernesto Pérez-Chavela, Juan M. Sánchez Cerritos (2017) "Euler-type relative equilibria in spaces of constant curvature and their stability" Canadian Journal of Mathematics, (por aparecer).

Jaime Andrade,  Ernesto Pérez-Chavela, Claudio Vidal (2017) "The restricted three body problem on surfaces of constant curvature" Journal of Differential Equations,(por aparecer).

Jaime Andrade,  Ernesto Pérez-Chavela, Claudio Vidal (2017) "Regularization of the  Circular Restricted Three Body Problem on Surfaces of Constant Curvature" Journal of Dynamics and Differential Equations (por aparecer).

David Asperó and Miguel Angel Mota (2017) "Measuring club-sequences together with the continuum large", The Journal of Symbolic Logic, volume 82, issue 3 September 2017, pp. 1066-1079
DOI: 10.1017/jsl.2017.4

Luis Franco-Pérez, Marian Gidea, Mark Levi, Ernesto Pérez-Chavela (2016) "Stability interchanges in a curved Sitnikov problem". Nonlinearity, 29 No. 3, 1056-1079

Luis C. García-Naranjo, Juan C. Marrero, Ernesto Pérez-Chavela, Miguel Rodríguez-Olmos (2016) "Classification and stability of relative equilibria for the two-body problem in the hyperbolic space of dimension 2." Journal of Differential Equations, 260, Issue 7, 6375–6404.

Jaime Andrade, Nestor Dávila, Ernesto Pérez-Chavela, Claudio Vidal (2017) "Dynamics and regularization of the Kepler problem on surfaces of constant curvature" Canadian Journal of Mathematics, 69, 961-991.

Ernesto Pérez-Chavela, Claudia Tamayo (2016) "Relative Equilibria in the 4-Vortex Problem Bifurcating from an Equilateral Triangle Configuration." Applied Mathematics and Nonlinear Sciences (AMNS),1, 1, 301-310.
DOI: 10.21042/AMNS.2016.1.00025

I.Sandoval, E.Possani (2016) "An analysis of different representations for vectors and planes in R3", Educational Studies in Mathematics, pp 1 -19.
DOI: 10.1007/s10649-015-9675-2

P. Castañeda; F. Furtado (2016) "The role of sonic shocks between two- and three-phase states in porous media", Bulletin of the Brazilian Mathematical Society, New Series, 47(1), 227-240.
DOI: 10.1007/s00574-016-0134-1

S. Berres; P. Castañeda (2016) "Identification of shock profile solutions for bidispersive suspensions", Bulletin of the Brazilian Mathematical Society, New Series, 47(1), 105-115.
DOI: 10.1007/s00574-016-0125-2

David Fernández Duque, Valentin Goranko. "Secure aggregation of distributed information: How a team of agents can safely share secrets in front of a spy". Discrete Applied Mathematics
198: 118-135 (2016). ISSN: 0166-218X

David Asperó and Miguel Angel Mota, "Separating club-guessing principles in the presence of fat forcing axioms", Annals of Pure and Applied Logic, 167 (2016), pp. 284-308

L. Franco-Perez, E. Perez-Chavela, "The symmetric elliptic and hyperbolic restricted 3-body problem on the unit circle", Journal of Geometry and Physics (2016), Vol 99, pp 28 - 41.

P. Castañeda, E. Abreu, F. Furtado and D. Marchesin (2016) "On a universal structure for immiscible three-phase flow in virgin reservoirs", Comput. Geosci. 20: 171-185.

Morais, J.; Pérez-de la Rosa, M. A.; Kou, K. I. "Computational geometric and boundary value properties of oblate spheroidal quaternionic wave functions". Wave Motion 57 (2015), 112–128. ISSN: 0165-2125

J. Morais, M.H. Nguyen and K.I. Kou. "On 3D orthogonal prolate spheroidal monogenics". Mathematical Methods in the Applied Sciences. Vol. 39, No. 4, 635-648 (2016). ISNN: 0170-4214
DOI: 10.1002/mma.3505

Pérez-Chavela, E.; Santoprete, Manuele; Tamayo, Claudia. "Symmetric relative equilibria in the four-vortex problem with three equal vorticities". Dyn. Contin. Discrete Impuls. Syst. Ser. A Math. Anal. 22 (2015), no. 3, 189–209. ISSN: 1201-3390

David Fernández Duque, Ángel Nepomuceno-Fernández, Enrique Sarrión-Morillo, Fernando Soler-Toscano, Fernando R. Velázquez-Quesada "Forgetting complex propositions". Logic Journal of the IGPL 23(6): 942-965 (2015). ISSN: 1367-0751

Aguilar, Juan C. "Higher-order Newton-Cotes rules with end corrections". Appl. Numer. Math. 88 (2015), 66–77. ISSN:0168-9274

Bosch, C.; García, C. L.; Garibay-Bonales, F.; Gómez-Wulschner, C.; Vera, R. "Ekeland's variational principle and critical points of dynamical systems in locally complete spaces". Ann. Funct. Anal. 6 (2015), no. 4, 107–113. ISNN: 2008-8752

Martínez Sánchez, J.; Zaitseva, E. "Note on stability estimation in average Markov control processes". Kybernetika (Prague) 51 (2015), no. 4, 629–938. ISSN: 0023-5954
DOI: 10.14736/kyb-2015-4-0629

John Krueger and Miguel Angel Mota, "Coherent adequate forcing and preserving CH", Journal of Mathematical Logic Vol. 15, No. 2 (2015) 1550005 (34 pages)

Ana Paulina Figueroa, Eduardo Rivera-Campo, "A counterexample to a result on the tree graph of a graph", Australasian Journal of Combinatorics 63(3) (2015), 368-373.

L.C. Thomas, T. Archibald, E. Possani,"Managing inventory and production capacity in start-up firms", Journal of the Operational Research Society Vol. 66 (2015), Issue 10, pp. 1624–1634

Ana Paulina Figueroa, Mika Olsen, Rita Zuazua, "On the vertices of a 3-partite tournament not in triangles"Discrete Mathematics, 338 (11) (2015), 1982-1988.

Marta Cabo, Edgar Possani, "Considerations on Applying Cross Entropy Methods to the Vehicle Routing Problem", International Journal of Combinatorial Optimization Problems and Informatics, Vol. 6, No. 3, Sep-Dec 2015, pp. 22-33. ISSN: 2007-1558.
artículo en pdf

Marta Cabo, Edgar Possani, Chris N. Potts, Xiang Song, "Split–merge: Using exponential neighborhood search for scheduling a batching machine", Computers & Operations Research, Volume 63, November 2015, Pages 125-135, ISSN 0305-0548

V. Matos, P. Castañeda, D. Marchesin (2014) "Classification of the umbilic point for general immiscible three-phase flow in porous media". Fourteenth International Conference devoted to Theory, Numerics and Applications of Hyperbolic Problems 2012, Padova, Italia. AIMS Applied Mathematics Vol. 8: 791-799.
artículo en pdf

P. Castañeda, F. Furtado, D. Marchesin (2014) "On singular points for convex permeability models". Fourteenth International Conference devoted to Theory, Numerics and Applications of Hyperbolic Problems 2012, Padova, Italia. AIMS Applied Mathematics Vol. 8: 415-422.
artículo en pdf

Thomas E. Gilsdorf, Mohammad Khavanin (2013) "Existence and uniqueness for nonlinear integro-differential equations in real locally complete spaces."  Scientiae Mathematicae Japonicae, vol. 76, No. 3 , p. 395 - 400.
manuscrito en pdf

Fedorov Y.N., García-Naranjo L.G., Vankershaver J.(2013) "The Motion of the 2D Hydrodynamic Chaplygin Sleigh in the Presence of Circulation", Discrete and Continuous Dynamical Systems, Vol 33, No 9, pp. 4017–4040.

Trigueros M. and Possani E. (2013) "Using an economics model for teaching linear algebra." Linear Algebra and its Applications, 438, pp. 1779–1792.

de la Llave R. and Lomelí H.E. (2012) "Invariant Manifolds for Analytic Difference Equations." SIAM J. Appl. Dyn. Syst. 11, no. 4, pp. 1614–1651.

Dullin H.R., Lomelí H.E. and Meiss J.D. (2012) "Symmetry reduction by lifting for maps." Nonlinearity 25, no. 6, pp. 1709– 1733.

Balseiro P. and García-Naranjo, L.C., (2012) "Gauge transformations, twisted Poisson brackets and Hamiltonization of nonholonomic systems." Arch. Rat. Mech. Anal. 205 , no. 1, pp. 267-310.

Morales J.L., Nocedal J. and Wu Y. (2012) "A Sequential Quadratic Programming Algorithm with an Additional Equality Constrained Phase." Journal of Numerical Analysis, Vol. 32, No. 2, pp. 553-579.

Bosch, C., Gilsdorf T.E. and Gómez-Wulschner C. (2011) " Mackey first countability and docile locally convex spaces." Acta Mathematica Sinica, English Series, Vol. 27 No. 4, pp.737-740.

Glass C.A., and Possani E. (2011) "Lot Streaming Multiple Jobs in a Flowshop". International Journal of Production Research, Vol. 49, Issue 9, pp.2669-2681.

Rodrigo M.R. and Miura R.M. (2011) "Exact and approximate traveling waves of reaction-diffusion systems via a variational approach". Analysis and Applications, Vol. 9, No. 2, pp. 187-199.

Rodrigo M.R. and Mamon R.S. (2011) "A unified approach to explicit bond price solutions under a time-dependent affine term structure modelling framework" Quantitative Finance, Vol. 11, No. 4, pp. 487-49. doi:10.1080/14697680903341798

Feng L., Linetsky V., Morales J.L., and Nocedal J (2011) " Remark on Algorithm 778: L-BFGS-B: Fortran Subroutines for Large-Scale Bound Constrained Optimization" ACM Transactions on Mathematical Software, Vol. 38, No.1.

Bosch C., García A., Gómez-Wulschner C., and S. Hernández- Linares (2010) " Equivalents to Ekeland's Variational Principle in Locally Complete Spaces " Scientiae Mathematicae Japonicae, Vol. 72, No. 3, pp.283-287

Possani E., Trigueros M., Preciado J.G., Lozano M.D. (2010) "Use of models in the Teaching of Linear Algebra" Linear Algebra and its Applications, Vol. 432, Issue 8, pp. 2125-2140. doi:10.1016/j.laa.2009.05.004

Feng L., Linetsky V., Morales J.L., and Nocedal J. (2010) " On the Solution of Complementarity Problems Arising in American Options Pricing" Optimization Methods and Software. (online available since Aug 2010- awaiting volume and page numbering)

Mireles James M.-J. D. and Lomelí H. (2010) "Computation of Heteroclinic Arcs with Application to the Volume Preserving Hénon Family " SIAM J. Applied Dynamical Systems, Vol. 9, No. 3, pp. 919-953. doi:10.1137/090776329

Domínguez-Soria V.D., Geudtner G., Morales J.L., Calaminici P. and Köster A (2009). "Robust and Efficient Density Fitting", Journal of Chemical Physics, Vol. 131, Issue 12.

Caserta M., and Cabo Nodar M., (2009) "A cross entropy based algorithm for reliability problems", Journal of Heuristics, Vol. 14, No. 5, pp. 479-501.

Lomelí H. E., and Meiss J. D. (2009) "Resonance zones and lobe volumes for exact volume-preserving maps", Nonlinearity, Vol. 22, pp. 1761-1789.

Fasano A., Herrero M.A., and Rodrigo M.R. (2009) "Slow and fast invasion waves in a model of acid-mediated tumour growth", , Mathematical Biosciences, Vol. 220, pp. 45-56.

Morales J.L., Fasano G. and Nocedal J. (2009) "On the Geometry Phase in Model-Based Algorithms for Derivative-Free Optimization", Optimization Methods and Software, Vol. 24, Issue 1, pp. 145-154.

Lomelí H.E. and Meiss J.D. (2009) "Generating forms for exact volume-preserving maps", Discrete and Continuous Dynamical Systems Series S, Vol. 2, No. 2, pp. 361-377.

Aguilar J.C., and Chen Y. (2008) "High-order quadrature rules for acoustic scattering calculations", International J. Contemp. Math. Sci., Vol. 3 , No. 2, pp. 71-82.

Morales J.L. , Nocedal J., and Smelyanskiy M. (2008) " An Algorithm for the Fast Solution of Symmetric Linear Complementarity Problems", Numerische Mathematik, Vol. 111, Issue 2, pp. 251-266.

Lomelí H.E. , and Ramírez-Ros, R. (2008) "Separatrix Splitting in 3D Volume-Preserving Maps" SIAM J. Applied Dynamical Systems, Vol. 7, No. 4, pp. 1527 -1557.

Aguilar J. C. (2008) "High-order corrected trapezoidal quadrature rules for functions with a logarithmic singularity on a circle", Int. J. Contemp. Math. Sci., Vol. 3 , No. 25-28, pp. 1133-1140.

Rodrigo M.R. , and Mamon R. (2008), "A new representation of the local volatility surface", International Journal of Theoretical and Applied Finance, Vol. 11, Issue 7, pp. 691-703.

Lomelí H.E. , et al. (2008), "Canonical Melnikov theory for diffeomorphisms", Nonlinearity, Vol. 21, pp. 485-508.

Archibald T.W. , Thomas L.C., Possani E. (2007)"Keep or return? Managing ordering and return policies in start-up companies.", European Journal of Operational Research, Vol. 179, Issue 1, pp.97-113.

Charalambous N. (2007),"On the Equivalence of Heat Kernel Estimates and Logarithmic Sobolev Inequalities for the Hodge Laplacian",Journal of Differential Equations, Vol. 233, pp. 291-312. doi:10.1016/j.jde.2006.10.007

Trigueros M., Lozano M. D., and A. E. Lage. (2007) "Development and use of a computer based resource for teaching and learning probability in primary classroom" International Journal for Technology in Mathematics Education, Vol. 13, No. 4, pp. 205-211.

Rodrigo M. , Mamon R. (2007), "Recovery of time-dependent parameters of a Black-Scholes-type equation: An inverse Stieltjes moments approach", Journal of Applied Mathematics.

Castro Pérez J., González Peláez M., and Ríos Montes J. (2007), "Some aspects of $\tau$-full modules" , East-West J. Math., Vol. 9, No. 2, pp. 139-159.

Rodrigo M. R. ,Mamon R. S. (2007),"An application of Mellin transform techniques to a Black-Scholes equation problem", Analysis and Applications, Vol. 5, No. 1, pp. 1-16

Aguilar J. C. (2007) "An unconditionally $A$-stable method for initial value problems based on Simpson's rule" , Int. Math. Forum, Vol. 2 , No. 53-56, pp. 2771-2779

Bosch, C., García A. and García C. L. (2007) "An Extension of Ekcland's Variational Principle to Locally Complete Spaces" , Journal of Mathematical Analysis and Applications, No. 328, pp. 106-108.

Herrero, Miguel A., Rodrigo, M.R. (2007)"Remarks on accessible steady states for some coagulation fragmentation systems", Discrete and Continuous Dynamical Systems, Vol. 17, Issue 3, pp.541-552

Lomelí H.E., and Calleja R. (2006) "Heteroclinic bifurcations and chaotic transport in the two-harmonic standard map" , Chaos, Vol. 16, No. 8, pp. 023117.

Bosch C., García C. L., Garybay-Bonales F., Gómez-Wulschner C. and Vera R. (2006) "Locally Complete Spaces, Regularity, and the Banach Disk Closure Property ", International Mathematical Forum, Vol. 1, No. 8, pp. 351-357

Lomelí H.E. (2006), "Heteroclinic Orbits and Rotation Sets for Twist Maps", Discrete and Continuous Dynamical Systems, Vol. 14, No.2 , pp. 343-354.

Rodrigo M. R., and Mamon R. S. (2006), "An alternative approach to solving the Black-Scholes equation with time-varying parameters", Applied Mathematics Letters, Vol. 19, pp. 398-402.

Lomelí, H.E., and Garcia, C. L. (2006) "Variations on a theorem of Korovkin", Amer. Math. Monthly, Vol. 113, No. 8, pp. 744-750.

Aguilar J.C., and Goodman J.B. (2005), "An Efficient Interpolation Algorithm on Anisotropic Grids for Functions with Jump Discontinuities in 2-D", Applied Numerical Mathematics, Vol. 55, pp. 137-153.

Aguilar J.C., and Chen Y. (2005), "High-Order Corrected Trapezoidal Quadrature Rules for the Coulomb Potential in Three Dimensions", Computers and Mathematics with Applications, Vol. 49, No. 4, pp. 625-631.

Charalambous N.(2005),"On the $L^p$ Independence of the Spectrum of the Hodge Laplacian on Non-Compact Manifolds.", Journal of Functional Analysis, Vol. 224, pp. 22-48.

Lomelí H.E. (2005), "Symplectic Homomogeneous Diffeomorphisms, Cremona Maps and jolt Representation", Nonlinearity, Vol.18, pp. 1065-1071.

Waltz R.A., Morales J.L., Nocedal J., and Orban D. (2005), "An Interior Algorithm for Nonlinear Optimization that Combines Line Search and Trust region Steps", Mathematical Programming Series A, Vol. 107, No.3, pp. 391-408.

Pastor G. (2005), "On the homotopy type of complete intersections", Topology, Vol.44, pp. 249-260.

Mamon R. S., and Rodrigo M. R. (2005), "Explicit solutions to European options in a regime-switching economy", Operations Research Letters, Vol. 33, pp. 581-586.

Herrero M. A., and Rodrigo M. (2005), "A note on Smoluchowski's equations with diffusion", Applied Mathematics Letters, Vol. 18, pp. 969-975.

Gómez Wulschner C., and Kucera J. (2004),"Sequentially Complete Inductive Limits and Regularity", Czechoslovak Mathematical Journal, Vol. 54, No. 129, pp.697-699.

Dufty J.W., Baskaran A. , and Zogaib L.(2004), "Gaussian Kinetic Model for Granular Gases", Physical Review, E69 51301, pp 1-17.

Rodrigo M., and Mimura M. (2004), "On some classes of linearizable reaction -convection - diffusion equations", Analysis and Applications, Vol. 2, No. 1, pp. 1-8.

García García C.L. and Johnson W.B. (2003), "Power Type Uniform Convexity of X via p-Asymptotic Uniform Convexity of Lr(X)", Houston Journal of Mathematics, Vol.29, No.2, pp. 395-404.

Possani E., Archibald T.W., and Thomas L.C. (2003)"Loans, Ordering and Shortage Costs in Start-ups: a dynamic stochastic decision approach.", Journal of the Operational Research Society, Vol. 54, No. 5, pp. 539-548.

Thomas L.C., Possani E., and Archibald T.W. (2003)"How useful is commonality? Inventory and production decisions to maximize survival probability in start-ups.", IMA Journal of Management Mathematics, Vol. 14, pp.305-320.

Rodrigo M. (2003), "Evolution of bounding functions for the solution of the KPP-Fisher equation in bounded domains", Studies in Applied Mathematics, Vol. 110, pp. 49-61.

Morales Perez J. L., Nocedal J., Waltz R., Liu G., and Goux J-P.. "Assessing the Potential of Interior Methods for Nonlinear Optimization (2003): Large-Scale PDE-Constrained Optimization". L.T. Biegler, O. Ghattas, M. Heinkenschloss, and B. van Bloemen Wanders (Eds.) Series: Lecture Notes in Computational Science and Engineering. Volume. 30, pp. 167-183. Springer-Verlag. Heidelberg.

Aguilar, J.C.. and Chen Y. (2002) "High-Order Corrected Trapezoidal Quadrature Rules for Functions with a Logarithmic Singularity in 2-D", Computers and Mathematics with Applications, Vol. 44, No. 8-9, pp. 1031-1039.

Bosch Giral C., Gilsdorf T. ,and Gómez Wultschner C., and Vera R. (2002) "Local Completeness of Ip(E),1<=p< infinity", International Journal of Mathematics and Mathematical Sciences, Vol.31, No. 11, pp. 651-657.

Bosch Giral C., García A., and Gilsdorf T. (2002) "Some Hereditary Properties of Iinf(E) from E", International Mathematical Journal, Vol.2, No. 11, pp. 1061-1066.

Bosch Giral C., and Kucera J. (2002) "Sequential Completeness and Regularity of Inductive Limits of Webbed Spaces", Czechoslovak Mathematical Journal, Vol.52, No.127, pp. 329-332.

Lomelí H., and Temzelides T. (2002), "Discrete Time Dynamics in a Random Matching Monetary Model", Economic Theory, Vol.20, No.2 , pp. 259-269.

Morales J.L. (2002), "A Numerical Study of Limited memory BFGS Methods", Applied Mathematics Letters, Vol. 15, No. 4 ,pp. 481-487.

Morales J.L., and Nocedal J. (2002), "Enriched Methods for Large-Scale Unconstrained Optimization", Computational Optimization and Applications (COAP), Vol.21, No.2, pp. 143-154.

Rodrigo M.R., adn Mimura M. (2002), "Annihilation dynamics in the KPP-Fisher equation", European Journal of Applied Mathematics, Vol. 13, pp. 195-204.

González Peláez, M., and Teply M.L. (2001), "On Semihereditary and p.p. monoid Rings", Semigroup Forum, Vol.62, pp. 399-402.

Morales J.L., and Nocedal J. (2001), "Algorithm PREQN: Fortran Subroutines for Preconditioning the Conjugate Gradient", ACM Transactions on Mathematical Software, Vol.27, No.1, pp. 83-91.

Rodrigo M., and Mimura M. (2001), "Exact solutions of reaction-diffusion systems and nonlinear wave equations", Japan Journal of Industrial and Applied Mathematics, Vol. 18, pp. 657-696.

Rodrigo M., and Mimura M. (2001), "Front dynamics of the KPP-Fisher equation", Proceedings of the International Conference on Reaction-Diffusion Systems: Theory and Applications, Kyoto.

Rumbos B. (2001), "Representing Subjective Orderings of Random Variables: an Extension", Journal of Mathematical Economics, No.36, pp. 31-43.

Rumbos B., and Auernheimer L. (2001), "Endogenous Capital Utilization in a Neoclassical Growth Model", Atlantic Economy Journal, No.29, Issue 2, pp. 121-134.

Trigueros M. (2001), "Un Proyecto de enseñanza de la física con tecnología para la escuela secundaria", Revista de investigación y Experiencias Didácticas. Retos de la enseñanza para las Ciencias en el Siglo XXI, Tomo 1, Número Extraordinario, Barcelona, pp. 291-292.

Bosch Giral C., and García A. (2000) "Banach-Mackey, Locally Complete Spaces and Ip,q Summability", International Journal of Mathematics and Mathematical Sciences, Vol.23, No.10, pp. 675-679.

Gómez Wulschner C., and Kucera J. (2000),"Sequential Completeness of Inductive Limits", International Journal of Mathematics and Mathematical Sciences, Vol.24, No.6, pp. 419-421.

Lomelí H.E., and Meiss, J. (2000), "Heteroclinic Orbits and Transport in a Perturbed, Integrable Standard Map", Physics Letters A, Vol. 269, No. 5/6 , pp. 309-318

Lomelí H.E., and Meiss, J. (2000), "Heteroclinic Primary Intersections and Codimension one Melnikov Method for Volume Preserving Maps.", Chaos, Vol.10, No.1, pp. 109-121.

Morales J.L., and Nocedal J. (2000), "Automatic Preconditioning by Limited Memory Quasi-Newton Updates", SIAM Journal on Optimization, Vol.10, No.4, pp. 1079-1096.

Pastor G., Astey L. , Gitler S. and Micha E. (2000), "Parallelizability of Proyective Stiefel Manifolds", Proceedings of the American Mathematical Society, No.128, pp. 1527-1530.

Baker B., Cooley L., and Trigueros M. (2000), "A Calculus Graphing Schema", Journal for Research in Mathematics Education, Vol.31, No.5, pp. 557-578.

Rodrigo M., and Mimura M. (2000), "Exact solutions of a competition-diffusion system", Hiroshima Mathematics Journal, Vol. 30 , pp. 257-270.

Espinosa R. (1999), "A Qualitative method for Multicriteria Decision Aid", Investigación Operativa, Vol.8, pp. 77-86.

Pastor G., Astey L., Gitler S. and Micha E.(1999), "Cohomology of Proyective Stiefel Manifolds", Canadian Journal of Mathematics, No.51, pp. 897-914.

Rumbos B. (1999), "A Variable Rate of Capital Utilization and the Averch-Johnson Effect", Pennsylvania Economic Review, Vol.8, No. 1, pp. 52-61.