eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
327
330
10.22099/ijsts.2014.2083
2083
On the theory of strips and Joachimsthal theorem in the Lorentz space , 3
A. Tutar
atutar@omu.edu.tr
1
O. Sener
2
Ondokuz Mayıs University, Science and Arts Faculty, Department of Mathematics, 55139, Atakum, Samsun, Turkey
Ondokuz Mayıs University, Science and Arts Faculty, Department of Mathematics, 55139, Atakum, Samsun, Turkey
In this study the theory of strips and Joachimsthal Theorem in are generalized to Lorentz space , 3. Furthermore, the Joachimsthal Theorem is investigated when the strip is time-like and space-like.
http://ijsts.shirazu.ac.ir/article_2083_2e90d0ffa0ad15e2a15584a9c4a564d1.pdf
Curvature strip
semi-Euclidean space
Joachimsthal Theorem
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
331
340
10.22099/ijsts.2014.2084
2084
Numerical solution of nonlinear optimal control problems based on state parametrization
B. Kafash
bkafash@stu.yazduni.ac.ir
1
A. Delavarkhalafi
2
S. M. Karbassi
3
Faculty of Mathematics, Yazd University, Yazd, P.O. Box 89197/741, Iran
Faculty of Mathematics, Yazd University, Yazd, P.O. Box 89197/741, Iran
Faculty of Advanced Education, Islamic Azad University, Yazd Branch, Yazd, P.O.Box 89195/155, Iran
In this paper, solution of nonlinear optimal control problems and the controlled Duffing oscillator, as a special class of optimal control problems, are considered and an efficient algorithm is proposed. This algorithm is based on state parametrization as a polynomial with unknown coefficients. By this method, the control and state variables can be approximated as a function of time. Also, the numerical value of the performance index is obtained readily. The convergence of the algorithm is proved. To demonstrate reliability and efficiency of the proposed algorithm, the scheme is tested on some numerical examples.
http://ijsts.shirazu.ac.ir/article_2084_c69f285ac6417631eb1ffcd1ef35724b.pdf
Optimal control problems
state parametrization
control linear oscillator and duffing oscillator
weierstrass approximation theorem
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
341
349
10.22099/ijsts.2014.2085
2085
Some new double sequence spaces in 2-normed spaces defined by two valued measure
E. Savas
esavas@iticu.edu.tr
1
Department of Mathematics, Istanbul Commerce University, Uskudar, Istanbul, Turkey
In this paper, following the methods of Connor, we introduce some new generalized double difference sequence<br />spaces using summability with respect to a two valued measure, double infinite matrix and an Orlicz function in 2-normed spaces which have unique non-linear structure and examine some of their properties.
http://ijsts.shirazu.ac.ir/article_2085_3b99a9e4420bd0c07a971d79283eb10e.pdf
convergence
μ-statistical convergence
convergence in μ-density
Orlicz function
2-normed space
paranormed space
double sequence space
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
351
358
10.22099/ijsts.2014.2086
2086
On the convergence of the VHPM for the Zakharove-Kuznetsov equations
M. Matinfar
1
M. Ghasemi
2
M. Saeidy
3
Department of Mathematics, Faculty of Sciences, Mazandaran University, P.O. Box 47415-95447, Babolsar, Iran
Department of Mathematics, Faculty of Sciences, Mazandaran University, P.O. Box 47415-95447, Babolsar, Iran
Department of Mathematics, Faculty of Sciences, Mazandaran University, P.O. Box 47415-95447, Babolsar, Iran
In this paper, the variational homotopy perturbation method (VHPM) and its convergence is adopted for the<br />Zakharove-Kuznetsov equations (ZK-equations). The aim of this paper is to present an efficient and reliable<br />treatment of the VHPM for the nonlinear partial differential equations and show that this method is convergent.<br />The convergence of the applied method is approved using the method of majorants from Cauchy-Kowalevskaya<br />theorem of differential equations with analytical vector field.
http://ijsts.shirazu.ac.ir/article_2086_2ebee92b345b584f60258c34168703dc.pdf
Variational homotopy perturbation method
convergence
Zakharove-Kuznetsov equation
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
359
365
10.22099/ijsts.2014.2087
2087
The modified Exp-function method and its applications to the generalized K(n,n) and BBM equations with variable coefficients
E. M. E. Zayed
e.m.e.zayed@hotmail.com
1
Abdelaziz M. A. M.
2
Mathematics Department, Faculty of Science, Zagazig University, Zagazig, Egypt
Mathematics Department, Faculty of Science, Zagazig University, Zagazig, Egypt
In this article, the modified exp-function method is used to construct many exact solutions to the nonlinear<br />generalized K(n,n) and BBM equations with variable coefficients. Under different parameter conditions, explicit<br />formulas for some new exact solutions are successfully obtained. The proposed solutions are found to be<br />important for the explanation of some practical physical problems.
http://ijsts.shirazu.ac.ir/article_2087_602e34ed8c921b4e63ba5f28759abab8.pdf
Generalized K(n,n) equation with variable coefficients
generalized BBM equation with variable
coefficients
exact traveling wave solutions
exp-function method
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
367
370
10.22099/ijsts.2014.2088
2088
Bounds on the signed distance--domination number of graphs
D. A. Mojdeh
damojdeh@umz.ac.ir
1
B. Samadi
2
S. M. Hosseini Moghaddam
3
Department of Mathematics, University of Tafresh, Tafresh, Iran
School of Mathematics, Institute for Research in Fundamental Sciences (IPM) Tehran, Iran, P.O. Box 19395-5746
Shahab Danesh Institute of Higher Education, Qom, Iran
Let , be a graph with vertex set of order and edge set . A -dominating set of is a subset such that each vertex in has at least neighbors in . If is a vertex of a graph , the open -neighborhood of , denoted by , is the set , . is the closed -neighborhood of . A function 1, 1 is a signed distance- dominating function of , if for every vertex , Σ 1. The signed distance--domination number, denoted by ,, is the minimum weight of a signed distance--dominating function of . In this paper, we give lower and upper bounds on , of graphs. Also, we determine the signed distance--domination number of graph , (the graph obtained from the disjoint union by adding the edges , ) when 2.
http://ijsts.shirazu.ac.ir/article_2088_c5af88b0160d6586dccc3fe99fa04e5f.pdf
Signed distance--dominating function
th power of a graph
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
371
376
10.22099/ijsts.2014.2089
2089
On compact operators on the Riesz -difference sequence spaces-II
M. Basarir
basarir@sakarya.edu.tr
1
E. E. Kara
2
Department of Mathematics, Sakarya University, 54187, Sakarya, Turkey
Department of Mathematics, Bilecik University, 11210, Bilecik, Turkey
The compact operators on the Riesz sequence space 1 ∞ have been studied by Başarır and Kara, “IJST (2011) A4, 279-285”. In the present paper, we will characterize some classes of compact operators on the normed Riesz sequence spaces and by using the Hausdorff measure of noncompactness.
http://ijsts.shirazu.ac.ir/article_2089_c2027cef32b871f2fca064fba1e0101a.pdf
-difference sequence spaces
Hausdorff measure of noncompactness
compact operators
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
377
382
10.22099/ijsts.2014.2090
2090
On a class of locally dually flat Finsler metrics with isotropic S-curvature
A. Tayebi
1
E. Peyghan
epeyghan@gmail.com
2
H. Sadeghi
3
Department of Mathematics and Computer Science, University of Qom, Qom, Iran
Department of Mathematics and Computer Science, Arak University, Arak 38156-8-8349, Iran
Department of Mathematics and Computer Science, University of Qom, Qom, Iran
Dually flat Finsler metrics form a special and valuable class of Finsler metrics in Finsler information geometry,<br />which play a very important role in studying flat Finsler information structure. In this paper, we prove that every<br />locally dually flat generalized Randers metric with isotropic S-curvature is locally Minkowskian.
http://ijsts.shirazu.ac.ir/article_2090_2921a61244187cfec410862b01289418.pdf
Locally dually flat metric
S-curvature
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
383
389
10.22099/ijsts.2014.2091
2091
Interesting dynamic behavior in some discrete maps
L. M. Saha
lmsaha.msf@gmail.com
1
S. Prasad
2
G. H. Erjaee
3
Mathematical Sciences Foundation, N-91, Greater Kailash I, New Delhi, India
Department of Mathematics, University of Delhi, Delhi-110007, India
Mathematics Department, Shiraz University, Shiraz, Iran
Different discrete models of population dynamics of certain insects have been investigated under various feasible conditions within the framework of nonlinear dynamics. Evolutionary phenomena are discussed through bifurcation analysis leading to chaos. Some tools of nonlinear dynamics, such as Lyapunov characteristic exponents (LCE), Lyapunov numbers, correlation dimension, etc. are calculated for numerical studies and to characterize regular and chaotic behavior. These results are produced through various graphics. Chaotic evolutions of such insect population have been discussed as the parameters attain certain set of critical values. The results obtained are informative and very significant. The correlation dimension for evolution of insect population signifies certain fractal structure.
http://ijsts.shirazu.ac.ir/article_2091_34cd11f40f65ab6d55ba498e0d4cfb19.pdf
Bifurcation
Lyapunov exponent
periodic attractor
correlation dimension
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2014-09-01
36
Issue 3.1
391
394
10.22099/ijsts.2014.2092
2092
The uniqueness theorem for discontinuous boundary value problems with aftereffect using the nodal points
A. Dabbaghian
a.dabbaghian@iauneka.ac.ir
1
Sh. Akbarpour
2
A. Neamaty
3
Islamic Azad University, Neka Branch, Neka, Iran
Islamic Azad University, Jouybar Branch, Jouybar, Iran
Department of Mathematics, University of Mazandaran, Babolsar, Iran
In this paper, uniqueness theorem is studied for boundary value problem with "aftereffect" on a finite interval with discontinuity conditions in an interior point. The oscillation of the eigenfunctions corresponding to large modulus eigenvalues is established and an asymptotic of the nodal points is obtained. By using these new spectral parameters, uniqueness theorem is proved.
http://ijsts.shirazu.ac.ir/article_2092_d844507e488833158ba158a039e5ac73.pdf
Uniqueness Theorem
nodal Points
discontinuous conditions
eigenvalues
eigenfunctions
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2012-09-01
36
Issue 3.1
395
410
10.22099/ijsts.2012.2093
2093
Characterizations of ternary semigroups by ,qk -fuzzy ideals
M. Shabir
1
N. Rehman
noorrehman82@yahoo.com
2
Department of Mathematics Quaid-i-Azam University, Islamabad, Pakistan
Department of Mathematics Quaid-i-Azam University, Islamabad, Pakistan
In this paper we have generalized the concepts of ,q-fuzzy ideals, ,q-fuzzy quasi-ideals and<br />,q-fuzzy bi-ideals by introducing the concepts of k ,q -fuzzy ideals, k ,q -fuzzy quasiideals and k ,q -fuzzy bi-ideals in ternary semigroups and several related properties are investigated. Different characterizations of regular and weakly regular ternary semigroups by the properties of these ideals are given.
http://ijsts.shirazu.ac.ir/article_2093_57f7ed00a6d5cfe0e7519f9746427aae.pdf
Ternary semigroups
k ,q -fuzzy ideals
k ,q -fuzzy quasi-ideals
k ,q -
fuzzy bi-ideals
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2012-09-01
36
Issue 3.1
411
416
10.22099/ijsts.2012.2094
2094
Common fixed point theorems for sequences of mappings with some weaker conditions
Kh. Abd-Rabou
k_abdrabo@yahoo.com
1
Department of Mathematics, Faculty of Science, Zagazig University, Egypt Department of Mathematics, Community College, Shaqra University, Al-qawwiya, K. S. A
In this paper, we prove a common fixed point theorem for six mappings (two set valued and four single valued mappings) without assuming compatibility and continuity of any mapping on non complete metric spaces. To prove the theorem, we use a non compatible condition, that is, weak commutativity of type (KB). We show that completeness of the whole space is not necessary for the existence and uniqueness of common fixed point, and give an example to support our theorem. Also, we prove a common fixed point theorem for two self mappings and two sequences set-valued mappings by the same weaker conditions. Our results improve, extend and generalizes the corresponding results given by many authors.
http://ijsts.shirazu.ac.ir/article_2094_660d64be0d7f9e54361e77aa36b88c32.pdf
common fixed point
single and set-valued mappings
weak commutativity of type (KB)