008242   Sukavanam N;Tomar N K (Department of Mathematics, Indian Institute of Technology, Roorkee-247 667, Email: nsukvfma@iitr.ernet.in) : Approximate controllability of semilinear control systems with bounded delay. Int J mathl Sci 2006, 5(1), 77-84.

Approximate controllability of an abstract semilinear delay control system of the form dx(t)/dt = Ax(t)+u(t)+ f(t,x(t+θ),u(t)), where 0 ≤ t ≤ T and -h≤ θ ≤ 0, is proved under simple sufficient conditions on the system operators A, B and f. First considers a system without delay, and then extends the result for delay system. Result is illustrated with semilinear controlled heat equation.

15 ref

008241   Singh B P (Department of Mathematics, Faculty of Science and Technology, Mahatama Gandhi Kashi Vidyapeeth, Varanasi-221 001) : On submanifold of an unified structure manifold. Int J mathl Sci 2006, 5(1), 183-8.

Structure equations of the submanifold V_2m-r of an unified structure manifold V_2m have been obtained in the paper. It is interesting to note that if V_2m-r is the hypersurface of V_2m then this hypersurface is an almost paracontact metric manifold or an almost Norden contact metric manifold according as a = ± 1 or a = ± i. The necessary and sufficient condition for the submanifold V_2m-r to be an unified structure manifold has been obtained. Other theorems of the geometrical importance have also been derived.

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008240   Sameena K;Sunitha M S (Department of Mathematics, National Institute of Technology, Calicut-673 601, Email: sunitha@nitc.ac.in) : Strong arcs and maximum spanning trees in a fuzzy graph. Int J mathl Sci 2006, 5(1), 17-20.

Arc is strong if it is in at least one maximum spanning tree of a fuzzy graph.

9 ref

008239   Rana S S;Upadhyay S;Nath J D (Department of Mathematics, K.D. University, Jabalpur-482 001) : Modelling multiobjective transportation problem as group decision making. Int J mathl Sci 2006, 5(1), 135-45.

Method to solve the multiobjective transportation problem (MOXP) using Fuzzy logic has been introduce in the papaer. The multiobjective transportation problem consists of optimizing several competing objectives simultaneously. Uses the concept of fuzzy majority to solve the multiobjective transportation problem. Allowes flexibility by providing weightages to the various objectives. A transformation function is proposed to transform the multicriteria problem to a single criterion problem, which can be solved then by traditional methods.

5 ref

008238   Rajarama Bhat B V;Dey S;Zacharias J (Indian Statistical Institute, R.V. College Post, Bangalore-560 059, Email: bhat@isibang.ac.in) : Minimal cuntz-krieger dilations and representations of cuntz-krieger algebras. Proc Math Sci 2006, 116(2), 193-220.

Given a contractive tuple of Hilbert space operators satisfying certain A-relations show that there exists a unique minimal dilation to generators of Cuntz-Krieger algebras or its extension by compact operators. The Cuntz-Krieger dilation can be obtained from the classical minimal isometric dilation as a certain maximal A-relation piece. Define a maximal piece more generally for a finite set of polynomials in n noncommuting variables. Classify all representations of Cuntz-Krieger algebras O_A obtained from dilations of commuting tuples satisfying A-relations. The universal properties of the minimal Cuntz-Krieger dilation and the WOT-closed algebra generated by it is studied in terms of invariant subspaces.

24 ref

008237   Prasad A (Department of Mathematics, Banaras Hindu University, Varanasi-221 005) : Generalized pseudo-differential operator on some gevrey spaces. Int J mathl Sci 2006, 5(1), 121-33.

Continuity of the pseudo-differential operator h_μ,a is investigated on certain Gevrey spaces when the symbol of the pseudo-differential operator also belongs to a certain Gevrey class. It is shown that the product of two generalized pseudo-differential operators is a pseudo-differential operator. A sobolev space boundedness result is obtained.

7 ref

008236   Powar P L (Department of Mathematics and Computer Science, R.D. University, Jabalpur-482 001, Email: pvjrdvv@rediffmail.com) : Counterexample of polynomial bases for algebraic elements due to wachspress. Int J mathl Sci 2006, 5(1), 175-81.

Wachspress has discovered a new theory to generate polynomial bases over partitions of planar regions with arbitrary algebraic elements which achieve global continuity and degree-k patchwork approximation. Investigates that the analysis initiated by Wachpress is not applicable over a mesh of regular hexagons.

3 illus, 5 ref

008235   Pattabhiramacharyulu N C;Gandhi B K; Nagaratnam E (National Professor of Engg and Technology, , Warangal-506 004) : Steady helical flow of a second order thermo-viscous fluid in an annulus. Int J mathl Sci 2006, 5(1), 165-73.

Steady helical flow of an incompressible Koh-Eringen second order thermo-viscous fluid in an annular region bounded by two long concentric circular cylinders is studied. The cylinders are kept at constant temperatures, rotate with constant angular velocities Ω_a, Ω_b (b <62> a) about their common axis. Further they are in relative motion parallel to their length. The temperature gradient and viscous dissipation are neglected. The velocity and the temperature distributions are obtained by solving the momentum and energy equations together with the boundary conditions. The drag forces, viscous couples and stresses are also calculated. Special cases of purely rectilinear and rotary flows are examined. When the fluid is Newtonian, the viscous couple vanishes in rectilinear flow and the drag force vanishes in rotary flow. In contrast to this, these are non-zero in thermo-viscous fluid flows in cylindrical geometry.

1 illus, 5 ref

008234   Pattabhiramacharyulu N C;Gandhi B K;Anuradha K (National Professor of Engg and Technology, , Warangal-506 004) : Steady flow of a thermo viscous fluid between two parallel plates in relative motion. Int J mathl Sci 2006, 5(1), 147-64.

Steady flow of a second order thermo-viscous incompressible fluid between two non-permeable parallel plates is examined in this paper. The flow is generated by a constant pressure gradient down the plates over which a motion with a given velocity u₀ of upper plate, relative to the lower one along the direction of the pressure gradient is superimposed. The basic differential equations for the velocity and temperature fields together with appropriate boundary conditions have been solved numerically by employing a finite difference scheme, and the results are presented in the form of graphs and tables. As a special case the steady flow in the absence of pressure gradient is deduced.

8 illus, 9 tables, 4 ref

008233   Park J H;Park J K (Division of Mathematics Sciences, Pukyong National University, 599-1 Daeyeon 3-Dong, Nam-Gu, Pusan 608-737, South Korea) : Generalized fuzzy semi closed sets and generalizations of fuzzy continuous functions. Int Rev Fuzzy Math 2006, 1(1), 89-101.

Paper deals with generalizations of fuzzy continuous functions by using the concept of generalized fuzzy semi closed sets. A comparative study regarding the mutual inter-relations among these functions along with those functions obtained is made. Authors have introduced and studied the notions of gfs-connectedness, gfs-extremally disconnectedness and gfs-compactness.

10 ref

008232   Navalagi G;Abdul Jabbar A M (Department of Mathematics, KLE Society's, G.H. College, Haveri-581 110, Email: gnavalagi@hotmail.com) : Some remarks on completely alpha irresolute functions. Int J mathl Sci 2006, 5(1), 1-8.

Chae et al. (resp. Navalagi G. B. have studied the concept of NA-continuous (resp. completely α-irresolute) functions. Now, the aim of the paper is to note that NA-continuous functions and completely α-irresolute functions are the same definitions. Also, Investigates several new properties of completely α-irresolute functions are obtained. It is shown that, if f₁ and f₂ are completely α-irresolute functions of a space X into an α-Hausdorff space Y, then the set {x ε X:f₁ (x) = f₂(x)} is δ-closed in X.

20 ref

008231   Nashine H K (Department of Mathematics, Raipur Institute of Technology, Mandir Hasaud, Chhatauna-492 101, Email: hemantnashine@rediffmail.com) : Existence of best approximation result in locally convex space. Int J mathl Sci 2006, 5(1), 21-9.

Fixed point theorem of Das and Naik is generalized to locally convex spaces and the new result is applied to extend a recent result on invariant approximation of Jungck and Sessa. Some known results and are also extended and improved.

16 ref

008230   Nam K B;Choi S H (Department of Mathematics, University of Wisconsin-Whitewater, Whitewater, WI 53190, Email: namk@uww.edu) : Automorphisms of non-associative algebras containing F[x] II. J Computnl Math optimiz 2006, 2(1), 51-6.

Non-associative algebra automorphism group Aut_non(WN_0,0,1[0,2]) of the non-associative algebra WN(gn, m, s)_[0,r] is found in the paper [7]. We find the non-associative algebra automorphism group Aut_non(WN_{0,0,1[0,r]) in this paper where every automorphism of the automorphism groups is the composition of elementary maps [5], [6], [7], [8], [9].}

10 ref

008229   Mohanty D (Department of Mathematics, Seemanta College, Jharpokharia, Mayurbhanja, Orissa) : On the N, P_n, q_nk summability factors of infinite series. Int J mathl Sci 2006, 5(1), 62-75.

Theorem on generalized norlund summability factors has been proved.

5 ref

008228   Misra U K;Misra M;Rauto K (Department of Mathematics, Berhampur University, Berhampur-760 007) : Absolute Banach summability of fourier series. Int J mathl Sci 2006, 5(1), 39-45.

Result on Banach summability is established.

5 ref

008227   Kim Y C;Ko J M (Department of Mathematics, Kangnung, National University Gangneung, Gangwondo-210 702, Korea) : L-fuzzy topologies and L-fuzzy quasi-uniform spaces. Int Rev Fuzzy Math 2006, 1(1), 47-64.

L-fuzzy topology induced by the initial L-fuzzy (quasi-) uniform structure coincides with the initial L-fuzzy topology for each L-fuzzy topology induced by L-fuzzy (quasi-) uniform structures has been proved.

19 ref

008226   Jun Y B;Walendziak A (Department of Mathematics Education, Gyeongsang National University, Chinju-600 701, Korea, Email: ybjun@gnu.ac.kr) : Fuzzy ideals of pseudo MV-algebras. Int Rev Fuzzy Math 2006, 1(1), 21-31.

Notion of fuzzy (implicative) ideals of a pseudo MV-algebra is introduced, and its characterizations are established. Conditions for a fuzzy set to be a fuzzy ideal are given. Given a fuzzy set μ, the least fuzzy ideal containing μ is constructed.

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008225   Jun Y B;Song S Z (Department of Mathematics Education, Gyeongsang National University, Chinju-660 701, Korea, Email: ybjun@gnu.ac.kr) : Fuzzy ideals with operators in BCC-Algebras. Int Rev Fuzzy Math 2006, 1(1), 1-9.

Notions of BCC-algebras with operators (brie, Ω-BCC algebras) and Ω-fuzzy BCC-ideals of Ω-BCC-algebras are given. Some properties of Ω-fuzzy BCC-ideals of Ω-BCC-algebras are investigated.

11 ref

008224   He W S;Hu L X;Li W T (Department of Mathematics, Tianshui Normal University, Tianshui, Gansu-741 001 People's Republic of China) : Global attractivity of a rational recursive sequence. Int J mathl Sci 2006, 5(1), 85-93.

Boundedness, the periodic character and global attractivity of the recursive sequence has been investigated, x_n+1 = a + bx_n-1/A-x_nO, n = 0,1..., where a ≥ 0, b, A <62> 0 are real numbers, kε {1,2,...} and the initial conditions x-k,..., x₀ are arbitrary real numbers. shows that the positive equilibrium of the equation is a global attractor with a basin that depends on certain conditions posed on the coefficients.

16 ref

008223   Gasinski L;Motreanu D;Papageorgiou N (Institute of Computer Science, Jagiellonian University, ul. Nawojki 11, 30072, Cracow, Poland, Email: npapg@math.ntua.gr) : Multiplicity of nontrivial solutions for elliptic equations with nonsmooth potential and resonance at higher eigenvalues. Proc Math Sci 2006, 116(2), 233-55.

Semilinear elliptic equation with a nonsmooth, locally Lipschitz potential function (hemivariational inequality) has been considered. Hypotheses permit double resonance at infinity and at zero (double-double resonance situation). Approach is based on the nonsmooth critical point theory for locally Lipschitz functionals and uses an abstract multiplicity result under local linking and an extension of the Castro-Lazer-Thews reduction method to a nonsmooth setting, which develop here using tools from nonsmooth analysis.

2 illus, 36 ref

008222   Garg P C;Srivastava S K (Department of Statistics, Punjabi University, Patiala-147 002) : Measure for time dependent queueing system with feedback and service in batches of variable size. Int J mathl Sci 2006, 5(1), 109-19.

Transient solution of a single channel qgueueing system with feedback in which the units are occurring singly and are served in batches of variable size has been investigated. Inter arrival time and service time are exponentially distributed. Time dependent probabilities of exactly i arrivals and j departures are obtained explicitly. The marginal probability of exactly i arrivals and the mean number of arrivals are obtained. Some particular cases of interest are also obtained.

7 ref

008221   Ganesan K (Department of Mathematics, Faculty of Engineering and Technology, S.R.M. Institute of Science and Technology, Deemed University, Kattankulathur-603 203, Email: gansan_k@yahoo.com) : Duality in fuzzy linear programming problems. J Computnl Math optimiz 2006, 2(1), 35-49.

Fuzzy Linear Programming Problems involving symmetric trapezoidal fuzzy numbers has been discussed. Notion of fuzzy primal and dual linear programming problems have been introduced. By using a simple fuzzy ranking and a new set of arithmetic operations for symmetric trapezoidal fuzzy numbers. Weak and strong duality theorems for fuzzy linear programming problems involving symmetric trapezoidal fuzzy numbers have been proved.

16 ref

008220   Ganesan G;Latha D;Raghavendra Rao C (Department of Mathematics, Jayaprakash Narayan College of Engineering, Mahabubnagar, Andhra Pradesh, Email: elgee110201@yahoo.com) : Proper rough fuzzy sets. Int J mathl Sci 2006, 5(1), 9-15.

Under rough fuzzy approximation, the boundary of the given fuzzy set represents the region of ambiguity. In general, an Information system is updated based on several reasons. Clearly, it gives changes and modifications in the existing knowledge base. A mathematical model is derived to reduce the region of ambiguity by considering other knowledge base, which is a refinement of the existing one. The resultant rough fuzzy set is called the proper rough fuzzy set.

10 ref

008219   Gandhi B K;Upender Reddy G (NO, JNTU College of Fine Arts Masab Tank, Hyderabad-28) : Triangular numbers in the generalized pell sequence and generalized associated pell sequence. Int J mathl Sci 2006, 5(1), 95-108.

Positive integer N is called a "Triangular Number" if it is of the form N = m(m+1)/2, where m is an integer greater than zero. A positive integer N is called Generalized Triangular Number for any integer m. For a fixed integer α <62> 0, a new sequence is called Generalized Pell Sequence {P_n(^α)} is defined by P₀(^α)= 0, P₁(^α)= 1 and P_n+2(^α)= (α+1) p_n+1(^α)+ α(3α-1)/2 P_n(^α) for n ≥0 and Generalized Associated Pell Sequence {Q_n(^α)} is defined by Q₀(^α)= 1, Q₁(^α)= 1 and Q_n+2(^α)= (<97>+1)Q_n+1(^α)+ α (3α-1)/2 Q_n(^α) for n ≥0 there exists generalized numbers in the sequence {P_n(^α)} for n = 0, 1 and there exists triangular numbers in the sequence {Q_n(^α) for n = 0,1 and some other results relative to triangular numbers have been proved.

2 tables, 6 ref

008218   Folland G B (Department of Mathematics, University of Washington, Seattle, WA 98195-4350, USA, Email: folland@math.washington.edu) : Abstruse meets the applicable: some aspects of time frequency analysis. Proc Math Sci 2006, 116(2), 121-36.

Area of Fourier analysis connected to signal processing theory has undergone a rapid development in the last two decades. The aspect of the development that has received the most publicity is the theory of wavelets and their relatives, which involves expansions in terms of sets of functions generated from a single function by translations and dilations. However, there has also been much progress in the related area known as time-frequency analysis or Gabor analysis, which involves expansions in terms of sets of functions generated from a single function by translations and modulations. In the area there are some questions of a concrete and practical nature whose study reveals connections with aspects of harmonic and functional analysis that were previously considered quite pure and perhaps rather exotic. In the expository paper, I give a survey of some of these interactions between the abstruse and the applicable. It is based on the thematic lectures which I gave at the Ninth Discussion Meeting on Harmonic Analysis at the Harish-Chandra Research Institute in Allahabad in October 2005.

22 ref

008217   Dube M;Manocha V (Department of Statistics, M.D. University, Rohtak) : Stein-rule esimator under balanced loss. Int J mathl Sci 2006, 5(1), 31-7.

Performance properties of a weighted average estimator of Ordinary Least Squares have been studied and compared and Stein-rule considering balanced loss function proposed by Zellner (1994). Superiority conditions have been derived assuming error distribution to be non-normal.

7 ref

008216   Datta D (Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur-208 016, Email: ddatta@iitk.ac.in) : Efficient technique for handling infeasibility in sequential linear programming method. J Computnl Math optimiz 2006, 2(1), 11-23.

Sequential linear programming method is very simple, straightforward and a powerful method for solving even very large nonlinear optimization problems. However, the method lacks a proper technique for handling infeasibility, i.e., constraints violation. One technique goes on adding the most violated constiaint of a sequence in the formation of linear subproblems for later sequences, thus gradually increases the number of constraints. Another technique steers the infeasible design to the feasible region by moving along the gradient direction of the most violated constraint. Many techniques either do not response to the infeasibility or just restart the process. A new technique has been proposed here for handling infeasibility. Before forming the linear subproblem for next sequence, the technique steers the infeasible design along a direction which is the resultant of gradient directions of all violated constraints. The success of the technique has been presented through a few numerical examples.

8 ref

008215   Choi S H;Lee K S;Nam K B (Department of Mathematics, Jeonju University, Chon-ju-560 759, Email: chois @jj.ac.kr) : Automorphisms of non-associative algebras containing a polynomial ring. J Computnl Math optimiz 2006, 2(1), 1-10.

Shows that non-associative algebra WN(g_n,m, s)D₁ which contains the polynomial ring is simple and its symmetric semi-Lie algebra is simple. Non associative algebra automor-phism groups Aut_non (WN₀,0,1[0,1,...r]) and Aut_non (WN₀,1,0[0,1,...,r]) where every automorphism of the automorphism groups is the composition of elementary maps [2], [3], [6], [7], [8], [9], 10]. The results of the paper shows why we need the F-algebra automorphism group of an F-algebra automorphism group of a polynomial ring and its Laurent extension.

13 ref

008214   Charyulu V N;Gandhi B K;Venkat Raman P (NO, Kakatiya Institute Technology & Sciences, Warangal-506 015) : Flow through a straight porous tube of arbitrary cross section under the influence of uniform transverse magnetic field. Int J mathl Sci 2006, 5(1), 47-62.

MHD steady flow of a viscous in-compressible, slightly conducting fluid through an infinite long straight porous tube of arbitrary cross-section in the presence of a constant pressure gradient, under the influence of a uniform transverse magnetic field has been studied. A numerical difference scheme is employed. The equilateral and rectangular cross-sections situations are considered as special cases. An appropriate numerical solution for the velocity have been investigated and discussed for different situations. The effect of the permeability of the porous medium together with the magnetic parameter on the flow of the fluid is examined at length.

2 illus, 4 tables, 12 ref

008213   Changjian Z;Cheung W (Department of Information and Mathematics Sciences, College of Science, China Jiling University, Hangzhou-310 018, People's Republic of China, Email: chjzhao@163.com) : On p-quermassinte differences function. Proc Math Sci 2006, 116(2), 221-31.

Minkowski inequality and Brunn-Minkowski inequality for p-quermassintegral differences of convex bodies has been established. Further, give Minkowski inequality and Brunn-Minkowski inequality for quermassintegral differences of mixed projection bodies.

22 ref

008212   Chamizo F (Departamento de Matematicas, Facultad de Ciencias, Universidad Autonoma de Madrid, 28049 Madrid, Spain) : Non euclidean visibility problems. Proc Math Sci 2006, 116(2), 147-60.

Analog of visibility problems in hyperbolic plane (represented by Poincare half-plane model H), replacing the standard lattice Z x Z by the orbit z = i under the full modular group SL₂(Z) has been considerd. Visibility criterion and study orchard problem and the cardinality of visible points in large circles has been proved.

1 illus, 2 tables, 16 ref

008211   Caldas M;Navalagi G;Saraf R (Departamento de Matematica Aplicada, Universidade Federal Fluminense, Rua Mario Santos Braga, Email: gmamccs@vm.u@.br) : Weakly ∅-Open functions between fuzzy topological spaces. Int Rev Fuzzy Math 2006, 1(1), 103-13.

Introduce and characterize fuzzy weakly θ-open functions between fuzzy topological spaces as natural dual to the fuzzy weakly θ-continuous functions and also study these functions in relation to some other types of already known functions.q

14 ref

008210   Borkotokey S (Department of Mathematics, Dibrugarh University, Dibrugarh, Assam) : RΓ-submodules in fuzzy setting. Int Rev Fuzzy Math 2006, 1(1), 33-46.

Notion of a fuzzy RΓ-submodule has been introduced and investigate some of its properties. Given the idea of a faithful and regular fuzzy RΓ-submodule and establish a relation between the two properties therein. Further, an existence and uniqueness theorem of a left (right) quasi-faithful fuzzy ideal of the corresponding I-ring with the help of an isomorphism defined on its RΓ-module is obtained. Derive RΓ-submodules, which are characterized by some functional equation. The notion of a R-normal fuzzy RΓ-submodule is given in the end and investigate some related properties.

8 ref

008209   Bhatt S J (Department of Mathematics, Sardar Patel University, Vallabh Vidyanagar-388 120, Email: subhashbhaib@yahoo.co.in) : Enveloping σ-C*-algebra of a smooth frechet algebra crossed product by R, K-theory and differential structure in C*-algebras. Proc Math Sci 2006, 116(2), 161-73.

Given an m-tempered strongly continuous action a of R by continuous automorphisms of a Frechet *-algebra A, it is shown that the enveloping σ-C*-algebra E(S(R, A^∞, α)) of the smooth Schwartz crossed product S(R, A^∞, α) of the Frechet algebra A^∞ of C^∞-elements of A is isomorphic to the σ-C*-crossed product C*(R,E(A), α) of the enveloping σ-C*-algebra E(A) of A by the induced action. When A is a hermitian Q-algebra, one gets K-theory isomorphism RK*(S(R, A^∞, α)) = K(C*(R, E(A), α) for the representable K-theory of Frechet algebras. An application to the differential structure of a C*-algebra defined by densely defined differential seminorms is given.

16 ref

008208   Bakhshi M;Mashinchi M;Borzooei R A (Department of Mathematics, Sistan and Baluchestan University Zahedan, Iran, Email: mbakhshi@hamoon.usb.ac.ir) : Representation theorem for some fuzzy algebraic hyperstructures. Int Rev Fuzzy Math 2006, 1(1), 73-87.

Representation Theorem in fuzzy set theory for some fuzzy algebraic hyperstructures, specially for fuzzy (weak) hyper BCK-ideals of a hyper BCK-algebra, fuzzy subhypergroups, fuzzy subhyperrings and fuzzy hyperideals have been given in the papaer.

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008207   Bagchi B (Indian Statistical Institute, R.V. College Post, Bangalore-560 059, Email: bbagchi@isibang.ac.in) : On nyman, beurling and baez-duarte's hilbert space reformulation of the riemann hypothesis. Proc Math Sci 2006, 116(2), 137-46.

There has been a surge of interest of late in an old result of Nyman and Beurling giving a Hilbert space formulation of the Riemann hypothesis. Many authors have contributed to the circle of ideas, culminating in a beautiful refinement due to Baez-Duarte. The purpose of the little survey is to dis-entangle the resulting web of complications, and reveal the essential simplicity of the main results.

7 ref

008206   Ali T (Department of Mathematics, Dibrugarh University, Dibrugarh-786 004) : Fuzzy quotient space of a vector space. Int Rev Fuzzy Math 2006, 1(1), 11-9.

Concept of cosets of a subspace in a vector space V generated by an element of the space and a translational invariant fuzzy subset μ of the space have been introduced. Some results analogous to certain basic results of the classical vector space have been proved. Quotient space of V generated by a subspace and μ have been defined.

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007241   Zengtai G;Hongxia Y (Coll of Math and Inf Sci, Northwest Norm Univ, LanZhou-730 070) : On regularity of caratheodory measure. Int J appl mathl Analysis Applic 2006, 1(1), 83-6.

Elementary example of irregular Caratheodory measure has been given.

3 ref

007240   Yoo S;Riahi D N (Dep of Theoretical and Appl Mechanics 216 Talbot Lab, Univ of Illinois Urbana, 104 S. Wright Street, Illinois 61801, USA, Email: d-riahi@uiuc.edu) : Numerical studies of flow instabilities in a channel with a moving wavy boundary. Int J appl mathl Analysis Applic 2006, 1(1), 101-28.

Flow in a channel with a moving wavy boundary is investigated in the subcritical domain where the Reynolds number R is below its critical value R_{c. The shear flow is bounded from above by a flat boundary and from below by a wavy boundary which moves at a constant speed in the streamwise direction. Both systems for the basic flow, due to the boundary wave and the Tollmien-Schlichting (TS) wave, and for the three-dimensional infinitesimal disturbances superimposed on the basic flow are solved numerically by using spectral collocation technique. Certain shape and speed of the wavy boundary were found to affect the flow stability, the parametric resonance, transition path and the spatial and temporal structure of the vortices which may evolve due to the three-dimensional instabilities of the basic flow.}

11 illus, 1 table, 27 ref

007239   Siddiqui A A (Dep of Math, The Univ of Lahore, 1 Km Raiwind Road, Lahore, Pakistan, Email: saakhlaq@gmail.com) : On unitaries in JB-algebras. Indian J Math 2006, 48(1), 35-48.

It is well known that JB*-algebras properly include all C*-algebras. Relationships between the distances from a point to the set of invertible elements have been looked and also to the set of unitaries in a JB*-algebra ℑ; various formulae are deduced for cases when the point is of norm ≤1, when ℑ is of tsr 1 and when ℑ is finite- dimensional. In the sequel, some results are obtained with particular focus on the notion of unitary rank of an element in connections with its distances to the unitaries and to the invertibles.

12 ref

007238   Sharma P R;Yadav G R (Dep of Math, Univ of Raj, Jaipur-302 004) : Three-dimensional flow and heat transfer through porous medium bounded by A porous vertical surface with variable permeability and heat source. Bull Calcutta Mathl Soc 2006, 98(3), 237-54.

Three dimwnsional flow and heat transfer through a viscous imcompressible fluid through porous medium bounded by a porous vertical surface in the presence of heat source and periodic permeablity of the medium has been investigated. The governing equastion of motion and energy are solved by the successive perturbation technique. The velocity and temperature distributions are derived, discussed numerically and shown through graphs. Skin-friction coefficient and the rate of the heat transfer in terms of the nusselt number at the surface are derived, discussed numerically and presented through graphs.

6 illus, 13 ref

007237   Roy T;Chaudhuri K S (Dep of Math, Vidyasagar Coll for Women 39, Shankar Ghosh Lane, Kolkata-700 006, Email: tapankabi@yahoo.co.in) : On a non-static single-decision procurement model for deteriorating items with ramp type demand, constant deterioration and shortage. Indian J Math 2006, 48(1), 83-101.

This study is concerned with an economic order quantity model for deteriorating items in which the demand rate of an item is of a ramp-type. It is assumed that a constant fraction of the on-hand inventory deteriorates per unit of time. The shortages in inventory which are fully backlogged are assumed. The model is discussed for an infinite time-horizon and the objective is to minimize the total inventory cost per unit time. Several numerical examples are taken up to illustrate the solution procedure and sensitivity analysis is also carried out.

6 illus, 1 table, 34 ref

007236   Ramakrishnan P V;Regina Mary P (Sch of Math, Madurai Kamaraj Univ, Madurai-625 021) : On R-Fuzzy closed maps. Bull Calcutta Mathl Soc 2006, 98(3), 221-8.

The notions, R-neighbourhood of a fuzzy point and N-compact spaces were introduced by (Wang 1983). The notion of Nearly Fuzzy T₂ spaces was introduced by (P.V. Ramakrishnan and V. Lakshmana Gomathy Nayagam 2000). R-fuzzy closed maps and their properties have been studied and characterised. Nearly Fuzzy T₂ spaces have been characterised, using convergent pseudo fuzzy filters. Also N-compact spaces with reference to R-fuzzy closed maps have been studied.

7 ref

007235   Rakhimov A A;Katz A A (Dep of Math, Karadeniz Tech Univ, Trabzon 61080, Turkey, Email: rakhimov@ktu.edu.tr) : Group actions on real w-algebras. Bull Calcutta Mathl Soc 2006, 98(3), 181-94.

Group actions on real W*-algebras have been considered. For injective semifinite real W*-algebras a classification (up to stably conjugate) of actions of compact abelian group in terms of cocycle conjugate of dual actions on the crossed product has been obtained. For injective real W*-factor of type III _λ, λ ≠ 1. with mod(α℘) = 1, a classification of actions of amenable discrete groups in terms of modular invariants is given.

14 ref

007234   Rajesh N;Ekici E (Dep of Math, Ponnaiyah Ramajayam Coll, Thanjavur-614 904, Email: nrajesh_topology@yahoo.co.in) : On weakly g-closed sets in topological spaces. Indian J Math 2006, 48(1), 49-56.

The concepts of weakly g^<126> -closed sets and weakly g^<126> -open sets in a topological space which are weaker forms of g^<126> -closed sets and g^<126> -open sets, respectively have been introduced. Many properties and relationships of such sets are investigated.

18 ref

007233   Rahman M;Mousavizadegan S H (Dep of Engng Math, Dalhousie Univ, Canada) : Hydrodynamic loading on offshore structures in nite depth ocean. Int J appl mathl Analysis Applic 2006, 1(1), 41-81.

Second-order wave loads are computed for the diffraction of monochromatic waves by a surface piercing vertical cylinder in the cases of finite and infinite fluid depth. The Weber transform that is an integral transform method similar to the Hankel transform with a more general kernel, is applied to compute the second-order force due to the second-order velocity potential. Different contours are applied to derive the analytical solution for the involved improper integrals. This makes the present solution distinct from the other available solution for the second-order forces. The contribution of each components of the second-order forces are computed and illustrated graphically.

11 illus, 19 ref

007232   patel T;Mehta M N (Math Sect ASH Dept., S.V.National institute of Technol, Surat-395 007) : A soloution of the burger's equation for longitudinal dispersioon of miscible fluid flow through porous media. Indian J Petrol Geol 2005, 14(2), 49-54.

Solution of the Burger's equation for longitudinal dispersion of miscible fluid flow through porous media have been obtained by using appropriate boundary conditions with assumption that velocity components in x direction of miscible fluid at any time is directly proposional to the concentration of the fluid at that time. The solution is more simplified under standard assumption.

2 illus, 9 ref

007231   Mohd Irfan (NO, Aligarh Muslim Univ, Aligarh-202 002) : On equalizers and limits in a comma category. Bull Calcutta Mathl Soc 2006, 98(3), 267-74.

A study of equalizers, coequalizers, limits and colimits in a comma category (T Å A), T is a functor from a category β to a category C and A is an object of C.

4 ref

007230   Mohapatra C K;Das N (NO, Inst of Math and Applics, Surya Kiran Building, Saheed Nagar, Bhubaneswar-751 022) : Composition operators on weighted hardy space. Indian J Math 2006, 48(1), 63-82.

It is shown that if θ : T → D is a continuous function then f o φ need not be in L²(T) for all f ∉ H²(T) and it is shown that for a particular class of sequences p(n), f o φ ∈ L²(T) for all f ∈ H²(p). Moreover, author study the boundedness and compactness of the composition operator Cφ : H²(p) → H²(p) defined by Cφf = f o φ, where f : D→ C is in H²(p) and φ : D → D is analytic. We have shown that sufficient conditions on φ such as (i) φ one-to-one or (ii) φ' ∈ H^∞ ensure the boundedness of the operator Cφ on H²(p). In each case the upper bounds on Cφhave been obtained. Further, using the concept of reproducing kernel a lower bound for <157><157>Cφ<157>< F128><157> whenever <157><157>Cφ<157>< F128><157> has a finite upper bound have been obtained. One last result of this paper deals with the compactness of Cφ it has been shown that if φ has angular derivative at some point z' on T and is bounded away from zero then Cφ cannot be a compact operator.

8 ref

007229   Mersal T F (Dep of Math Fac of Sci, Minufiya Univ, Shebin Elkoom, Egypt, Email: tmersal@yahoo.com) : Parallel curves and ruled surfaces. Int J appl mathl Analysis Applic 2006, 1(1), 1-10.

Theory of parallel immersions in Euclidean n-space was introduced by H. Farran and S. Robertson [J. London Math. Soc.(2)35(1987)]. The existence and uniqueness of the exterior parallelism of curves on a surface and the connection between parallelism and the so called total normal twist was partially considered in the previous works of the author. The aim of the work is to characterize and develop the notations of parallel curves and parallel rank for codimensions 1 and 2. Parallel curves and singularities on ruled surfaces are considered. Finally, introduce the notation of parallel normal surface and consider some of its local properties.

9 ref