eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
245
258
10.22099/ijsts.2006.2758
2758
DUAL SPLIT QUATERNIONS AND SCREW MOTION IN MINKOWSKI 3-SPACE
L KULA
1
Y. YAYLI
2
Ankara University, Faculty of Science, Department of Mathematics 06100 Tandogan, Ankara, Turkey
Ankara University, Faculty of Science, Department of Mathematics 06100 Tandogan, Ankara, Turkey
In this paper, two new Hamilton operators are defined and the algebra of dual split quaternions is<br />developed using these operators. It is shown that finite screw motions in Minkowski 3-space can be expressed<br />by dual-number ( 3×3 ) matrices in dual Lorentzian space. Moreover, by means of Hamilton operators, screw<br />motion is obtained in 3-dimensional Minkowski space 3<br />R1
http://ijsts.shirazu.ac.ir/article_2758_1cbee7993f19305b6988ff68bebce4a5.pdf
Dual split quaternions
semi-orthogonal dual matrix
screw-motion
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
259
269
10.22099/ijsts.2006.2759
2759
DISTRIBUTION OF NATURAL RADIONUCLIDES ON COASTS OF BUSHEHR, PERSIAN GULF, IRAN
M. R. ABDI
1
H. FAGHIHIAN
2
M. KAMALI
3
M. MOSTAJABODDAVATI
4
A. HASANZADEH
5
Department of Physics, University of Isfahan, Isfahan, 81747-73441, I. R. of Iran
2Department of Chemistry, University of Isfahan, Isfahan, 81747-73441, I. R. of Iran,
Central Laboratory, University of Isfahan, Isfahan, 81747-73441, I. R. of Iran
Department of Physics, University of Isfahan, Isfahan, 81747-73441, I. R. of Iran
Department of Physics, University of Isfahan, Isfahan, 81747-73441, I. R. of Iran
A reconnaissance study has been made on the distribution of 238U, 232Th, 40K, 137Cs and<br />geochemical features in soil and sediment samples at various locations on the coast of Bushehr in the Persian<br />Gulf. In this study a gamma-ray spectrometer based on a High Purity Germanium detector and a PC based<br />MCA and X-ray fluorescence (XRF) method were used. Estimation of the measured radionuclide content<br />have been made for the absorbed dose rate of gamma radiation. The Activity concentration (A), the equivalent<br />radium (Req), and the external hazard index (Hex) which resulted from the natural radionuclides in soil and<br />sediment are also calculated. The base-line data of radionuclides and heavy metals in view of the<br />commissioning of nuclear and non-nuclear industries for the coast of Bushehr, which does not yet exist, was<br />obtained.<br />Activity concentration levels due to radionuclides were measured in 50 soil and sediment samples<br />collected from this region. The measurement was performed with respect to their gamma radioactivity for a<br />counting time of 24 hour intervals. From the accumulated spectra, activity concentration were determined for<br />40K (range from 108 to 520 Bq Kg-1), 137Cs (from 6 to 40 Bq Kg-1), 238U (from 12 to 75 Bq Kg-1) and 232Th<br />(from 8 to 33 Bq Kg-1) with the lowest limit detection (LLD) of, respectively, 68, 3.2, 4.3 and 4.3 Bq Kg-1.<br />The dose rate from ambient air at the soil ranges was between 14 to 44 nGy h-1 with an average of 30.56±<br />7.86 nGy h-1.
http://ijsts.shirazu.ac.ir/article_2759_6983e9fdf689b15411792fca60efd854.pdf
Natural radionuclide
Gamma spectroscopy
Uranium
Thorium
Cesium
Potassium
HPGe
soil
Bushehr
Persian Gulf
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
271
277
10.22099/ijsts.2006.2760
2760
ON PROBLEMS REDUCED TO THE GOURSAT PROBLEM FOR A THIRD ORDER EQUATION
A. MAHER
1
YE. A. UTKINA
2
Department of Mathematics, Faculty of Science, Assiut University, Assiut, 71516, Egypt
Department of Mathematics, Faculty of Science, Assiut University, Assiut, 71516, Egypt
The aim of the present paper is the investigation of some problems which can be reduced to the<br />Goursat problem for a third order equation. Some results and theorems are given concerning the existence and<br />uniqunce for solving the suggested problem.
http://ijsts.shirazu.ac.ir/article_2760_30a04d57d4b9c238e515efa2ea47d9a0.pdf
Third order partial differential equation
goursat problem
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
279
283
10.22099/ijsts.2006.2762
2762
TEMPERATURE DEPENDENCE OF PHASE TRANSFORMATION PRESSURE IN SILICON
B. SALEHPOUR
1
M. OMIDFAR
2
Faculty of Physics, University of Tabriz, I. R. of Iran
Faculty of Physics, University of Tabriz, I. R. of Iran
In this experimental work the pressure induced phase transformation of silicon and Germanium<br />has been studied. It was shown that at a particular value of applied pressure, (Pt), depending on the sample<br />temperature, the electrical resistance of the specimen falls off to a metallic state. The main goal of this study<br />was to find out how the phase transformation pressure, Pt, for a p-type silicon varies with the sample<br />temperature. The results show that, the value of Pt decreases linearly as the temperature of the sample<br />increases. Meanwhile, other related results including the rate of resistance change in accordance with applied<br />pressure on the sample at different temperatures (~270-350K), both for the semiconductor and the metallic<br />state of the specimen were determined. In another effort, the amount of Pt for an n-type germanium, but only<br />at room temperature, was also determined.
http://ijsts.shirazu.ac.ir/article_2762_f1a322d21138b70413017871e17047f1.pdf
Phase transformation pressure
Silicon
Germanium
metallic state
temperature dependence
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
285
289
10.22099/ijsts.2006.2764
2764
COMPACT HYPERSURFACES IN EUCLIDEAN SPACE AND SOME INEQUALITIES
M. BEKTAS
1
M. ERGUT
2
Department of Mathematics, Fırat University, 23119 Elazig, Turkey
Department of Mathematics, Fırat University, 23119 Elazig, Turkey
Let (M,g ) be a compact immersed hypersurface of (Rn+1,<,>) , λ1 the first nonzero<br />eigenvalue, α the mean curvature, ρ the support function, A the shape operator, vol (M ) the volume of M,<br />and S the scalar curvature of M. In this paper, we established some eigenvalue inequalities and proved the<br />above.<br />1) 1 2 2 2 2<br />M M<br />A dv dv<br />n<br />∫ ρ ≥ ∫ α ρ ,<br />2)<br />( )<br />2 2 1 2<br />M 1 M<br />dv S dv<br />n n<br />α ρ ≥ ρ<br />∫ − ∫ ,<br />3) If the scalar curvature S and the first nonzero eigenvalue λ1 satisfy S = λ1 (n −1) , then<br />[ ] 2 1 2 0<br />M<br />dv<br />n<br />∫ α − λ ρ ≥ ,<br />4) Suppose that the Ricci curvature of M is bounded below by a positive constant k. Thus<br />( )<br />2 2 2 ( )<br />M 1 M<br />dv k gradf dv vol M<br />n n<br />α ρ ≥ +<br />∫ − ∫ ,<br />5) Suppose that the Ricci curvature is bounded and the scalar curvature satisfy S = λ1 (n −1) and L=k-<br />2S>0 is a constant. Thus<br />( ) 1 2 2 2 2 .<br />M M<br />vol M k dv S dv<br />L L<br />≥ − λ ∫ ψ αρ − ∫ α ρ
http://ijsts.shirazu.ac.ir/article_2764_6fdbbb662f474002837a48b18365eed9.pdf
First Eigenvalue
Support Function
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
291
295
10.22099/ijsts.2006.2766
2766
NUMERICAL SOLUTION OF THIRD-ORDER BOUNDARY VALUE PROBLEMS
G. B. LOGHMANI
1
M. AHMADINIA
2
Department of Mathematics, Yazd University, Yazd, I. R. of Iran
Department of Mathematics, University of Qom, Qom, I. R. of Iran
In this paper, we use a third degree B-spline function to construct an approximate solution for<br />third order linear and nonlinear boundary value problems coupled with the least square method. Several<br />examples are given to illustrate the efficiency of the proposed technique.
http://ijsts.shirazu.ac.ir/article_2766_f908d2cf7ec03192820bfef05797211c.pdf
B-spline
least square method
third order BVPs
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
297
314
10.22099/ijsts.2006.2770
2770
FUZZY β −IRRESOLUTE FUNCTIONS AND FUZZY β −COMPACT SPACES IN FUZZIFYING TOPOLOGY
O. R. SAYED
1
M. AZAB ABD-ALLAH
2
Department of Mathematics, Faculty of Science, Assiut University, Assiut 71516, Egypt
Department of Mathematics, Faculty of Science, Assiut University, Assiut 71516, Egypt
In this paper the concepts of fuzzifying β − irresolute functions and fuzzifying β − compact<br />spaces are characterized in terms of fuzzifying β − open sets and some of their properties are discussed.
http://ijsts.shirazu.ac.ir/article_2770_1914b4f628456398a7fcf535978c484c.pdf
Lukasiewicz logic
fuzzifying topology
β − irresoluteness
fuzzifying compactness
β − compactness
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
315
323
10.22099/ijsts.2006.2771
2771
NETWORK OPTIMIZATION WITH PIECEWISE LINEAR CONVEX COSTS
S. KETABI
1
Department of Management, University of Isfahan, I. R. of Iran
The problem of finding the minimum cost multi-commodity flow in an undirected and complete<br />network is studied when the link costs are piecewise linear and convex. The arc-path model and overflow<br />model are presented to formulate the problem. The results suggest that the new overflow model outperforms<br />the classical arc-path model for this problem. The classical revised simplex, Frank and Wolf and a heuristic<br />method are compared for the problem.
http://ijsts.shirazu.ac.ir/article_2771_6002b5bb53510cdb0aa0a5aae56fab6f.pdf
Multi-commodity network flow problem
piecewise linear and convex costs
Arc-path Model
Overflow
Model
Frank and Wolfe Method
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
325
341
10.22099/ijsts.2006.2772
2772
BRAIDING FROM 2-GROUPS TO 2-GROUPOIDS
E. ULUALAN
1
Department of Mathematics, Faculty of Science, University of Dumlupınar, Kütahya, Turkey
We give the concept of ‘braiding’ for 2-groupoids, and we show that this structure is equivalent to<br />braided regular, crossed modules.
http://ijsts.shirazu.ac.ir/article_2772_49fa4797bc2e9f7fd3d043c0c05b65a7.pdf
Braided crossed modules
cat-groups
internal category
monoidal category
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
343
347
10.22099/ijsts.2006.2773
2773
SEMI-ANALYTICAL SOLUTION OF STABILITY OF COMPOSITE ORTHOTROPIC CYLINDRICAL SHELLS UNDERTIME DEPENDENT A-PERIODIC AXIALCOMPRESSIVE LOAD
H. SOFIYEV
1
AL. H. SOFIYEV
2
E. YUSUFOGLU
3
Z. KARACA
4
1Department of Civil Engineering, Suleyman Demirel University, Isparta, Turkey
Technical Sciences Department, Kazakh Branch, Azerbaijan Teachers Institute, Kazakh, Azerbaijan
Department of Mathematics, Dumlupinar University, Kutahya, Turkey
Department of Civil Engineering, Ondokuz Mayis University, Samsun, Turkey
In this study, the stability problem of a circular orthotropic cylindrical shell under the effect of an<br />axial compression varying with a power function of time is considered. At first, the modified Donnell type<br />dynamic stability and compatibility equations are obtained using Love’s shell theory. Applying the Galerkin<br />method and Rayleigh-Ritz variational techniques to these equations and taking the large values of loading<br />parameters into consideration, analytics are obtained for critical parameter values. The results show that<br />critical parameters are affected by loading parameters variations, ratio of the Young’s moduli variations,<br />radius to thickness variations and the power of time in the axial compression expression variations.<br />Comparing results with those in the literature validates the present analysis.
http://ijsts.shirazu.ac.ir/article_2773_64b120ae53abfdb6bdc3f7f69c4963f4.pdf
orthotropic material
cylindrical shell
dynamic critical axial load
dynamic factor
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
349
354
10.22099/ijsts.2006.2774
2774
REGRESSION ANALYSIS IN MARKOV CHAIN
A. Y. ALAMUTI
1
R. MESHKANI
2
Department of Statistics, Shahid Beheshti University, Evin, Tehran, 19838, I. R. of Iran
Department of Statistics, Shahid Beheshti University, Evin, Tehran, 19838, I. R. of Iran
In a finite stationary Markov chain, transition probabilities may depend on some explanatory<br />variables. A similar problem has been considered here. The corresponding posteriors are derived and<br />inferences are done using these posteriors. Finally, the procedure is illustrated with a real example.
http://ijsts.shirazu.ac.ir/article_2774_087e665a3f96c6b1a75ad8e9d51a35a1.pdf
Bayes
Empirical Bayes
estimation
Markov chain
maximum likelihood
Regression
transition
probability matrix
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
355
362
10.22099/ijsts.2006.2775
2775
TOPOLOGICAL RING-GROUPOIDS AND LIFTINGS
A. FATIH OZCAN
1
I. ICEN
2
M. HABIL GURSOY
3
Inonu University, Science and Art Faculty Department of Mathematics, Malatya, Turkey
Inonu University, Science and Art Faculty Department of Mathematics, Malatya, Turkey
Inonu University, Science and Art Faculty Department of Mathematics, Malatya, Turkey
We prove that the set of homotopy classes of the paths in a topological ring is a topological ring<br />object (called topological ring-groupoid). Let p : X → X be a covering map and let X be a topological ring.<br />We define a category UTRCov(X) of coverings of X in which both X and X have universal coverings, and a<br />category UTRGdCov( π1X ) of coverings of topological ring-groupoid π1X , in which X and R0 = X have<br />universal coverings, and then prove the equivalence of these categories. We also prove that the topological<br />ring structure of a topological ring-groupoid lifts to a universal topological covering groupoid.
http://ijsts.shirazu.ac.ir/article_2775_f612489b5f4ee6a241d045d959f7d698.pdf
Fundamental groupoids
topological coverings
topological ring-groupoids
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
363
367
10.22099/ijsts.2006.2776
2776
SOME MAXIMAL INEQUALITIES FOR RANDOM VARIABLES AND APPLICATIONS
M. AMINI
1
A. BOZORGNIA
2
Department of Statistics, Ferdowsi University, Mashhad, I. R. of Iran
Department of Statistics, Ferdowsi University, Mashhad, I. R. of Iran
In this paper, we extend some famous maximal inequalities and obtain strong laws of large<br />numbers for arbitrary random variables by use of these inequalities and martingale techniques.
http://ijsts.shirazu.ac.ir/article_2776_0f0da3aaca17de5d99128ef36e67b026.pdf
Kolmogorove's inequality
Hajek-Renyi inequality
Strong law of large numbers
Martingale
eng
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
1028-6276
2006-12-28
30
3
369
374
10.22099/ijsts.2006.2777
2777
EXISTENCE OF THREE SOLUTIONS FOR THE DIRICHLET PROBLEM INVOLVING THE P-LAPLACIAN AND MINIMAX INEQUALITY FOR RELEVANT FUNCTIONALS
G. A. AFROUZI
1
S. HEIDARKHANI
2
Department of Mathematics, Faculty of Basic Sciences, Mazandaran University, Babolsar, I. R. of Iran
Department of Mathematics, Faculty of Basic Sciences, Mazandaran University, Babolsar, I. R. of Iran
In this paper, we establish some results on the existence of at least three weak solutions for a<br />Dirichlet problem involving p-Laplacian using a variational approach.
http://ijsts.shirazu.ac.ir/article_2777_1936b66f5699ec9bb6108332b0ea7f01.pdf
Dirichlet problem
critical point
three solutions
multiplicity results
minimax inequality