2018-05-25T15:18:06Z
http://ijsts.shirazu.ac.ir/?_action=export&rf=summon&issue=526
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
DUAL SPLIT QUATERNIONS AND SCREW MOTION IN MINKOWSKI 3-SPACE
L
KULA
Y.
YAYLI
In this paper, two new Hamilton operators are defined and the algebra of dual split quaternions isdeveloped using these operators. It is shown that finite screw motions in Minkowski 3-space can be expressedby dual-number ( 3×3 ) matrices in dual Lorentzian space. Moreover, by means of Hamilton operators, screwmotion is obtained in 3-dimensional Minkowski space 3R1
Dual split quaternions
semi-orthogonal dual matrix
screw-motion
2006
12
28
245
258
http://ijsts.shirazu.ac.ir/article_2758_1cbee7993f19305b6988ff68bebce4a5.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
DISTRIBUTION OF NATURAL RADIONUCLIDES ON COASTS OF BUSHEHR, PERSIAN GULF, IRAN
M. R.
ABDI
H.
FAGHIHIAN
M.
KAMALI
M.
MOSTAJABODDAVATI
A.
HASANZADEH
A reconnaissance study has been made on the distribution of 238U, 232Th, 40K, 137Cs andgeochemical features in soil and sediment samples at various locations on the coast of Bushehr in the PersianGulf. In this study a gamma-ray spectrometer based on a High Purity Germanium detector and a PC basedMCA and X-ray fluorescence (XRF) method were used. Estimation of the measured radionuclide contenthave been made for the absorbed dose rate of gamma radiation. The Activity concentration (A), the equivalentradium (Req), and the external hazard index (Hex) which resulted from the natural radionuclides in soil andsediment are also calculated. The base-line data of radionuclides and heavy metals in view of thecommissioning of nuclear and non-nuclear industries for the coast of Bushehr, which does not yet exist, wasobtained.Activity concentration levels due to radionuclides were measured in 50 soil and sediment samplescollected from this region. The measurement was performed with respect to their gamma radioactivity for acounting time of 24 hour intervals. From the accumulated spectra, activity concentration were determined for40K (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(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.The dose rate from ambient air at the soil ranges was between 14 to 44 nGy h-1 with an average of 30.56±7.86 nGy h-1.
Natural radionuclide
Gamma spectroscopy
Uranium
Thorium
Cesium
Potassium
HPGe
soil
Bushehr
Persian Gulf
2006
12
28
259
269
http://ijsts.shirazu.ac.ir/article_2759_6983e9fdf689b15411792fca60efd854.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
ON PROBLEMS REDUCED TO THE GOURSAT PROBLEM FOR A THIRD ORDER EQUATION
A.
MAHER
YE. A.
UTKINA
The aim of the present paper is the investigation of some problems which can be reduced to theGoursat problem for a third order equation. Some results and theorems are given concerning the existence anduniqunce for solving the suggested problem.
Third order partial differential equation
goursat problem
2006
12
28
271
277
http://ijsts.shirazu.ac.ir/article_2760_30a04d57d4b9c238e515efa2ea47d9a0.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
TEMPERATURE DEPENDENCE OF PHASE TRANSFORMATION PRESSURE IN SILICON
B.
SALEHPOUR
M.
OMIDFAR
In this experimental work the pressure induced phase transformation of silicon and Germaniumhas been studied. It was shown that at a particular value of applied pressure, (Pt), depending on the sampletemperature, the electrical resistance of the specimen falls off to a metallic state. The main goal of this studywas to find out how the phase transformation pressure, Pt, for a p-type silicon varies with the sampletemperature. The results show that, the value of Pt decreases linearly as the temperature of the sampleincreases. Meanwhile, other related results including the rate of resistance change in accordance with appliedpressure on the sample at different temperatures (~270-350K), both for the semiconductor and the metallicstate of the specimen were determined. In another effort, the amount of Pt for an n-type germanium, but onlyat room temperature, was also determined.
Phase transformation pressure
Silicon
Germanium
metallic state
temperature dependence
2006
12
28
279
283
http://ijsts.shirazu.ac.ir/article_2762_f1a322d21138b70413017871e17047f1.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
COMPACT HYPERSURFACES IN EUCLIDEAN SPACE AND SOME INEQUALITIES
M.
BEKTAS
M.
ERGUT
Let (M,g ) be a compact immersed hypersurface of (Rn+1,) , λ1 the first nonzeroeigenvalue, α the mean curvature, ρ the support function, A the shape operator, vol (M ) the volume of M,and S the scalar curvature of M. In this paper, we established some eigenvalue inequalities and proved theabove.1) 1 2 2 2 2M MA dv dvn∫ ρ ≥ ∫ α ρ ,2)( )2 2 1 2M 1 Mdv S dvn nα ρ ≥ ρ∫ − ∫ ,3) If the scalar curvature S and the first nonzero eigenvalue λ1 satisfy S = λ1 (n −1) , then[ ] 2 1 2 0Mdvn∫ α − λ ρ ≥ ,4) Suppose that the Ricci curvature of M is bounded below by a positive constant k. Thus( )2 2 2 ( )M 1 Mdv k gradf dv vol Mn nα ρ ≥ +∫ − ∫ ,5) Suppose that the Ricci curvature is bounded and the scalar curvature satisfy S = λ1 (n −1) and L=k-2S>0 is a constant. Thus( ) 1 2 2 2 2 .M Mvol M k dv S dvL L≥ − λ ∫ ψ αρ − ∫ α ρ
First Eigenvalue
Support Function
2006
12
28
285
289
http://ijsts.shirazu.ac.ir/article_2764_6fdbbb662f474002837a48b18365eed9.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
NUMERICAL SOLUTION OF THIRD-ORDER BOUNDARY VALUE PROBLEMS
G. B.
LOGHMANI
M.
AHMADINIA
In this paper, we use a third degree B-spline function to construct an approximate solution forthird order linear and nonlinear boundary value problems coupled with the least square method. Severalexamples are given to illustrate the efficiency of the proposed technique.
B-spline
least square method
third order BVPs
2006
12
28
291
295
http://ijsts.shirazu.ac.ir/article_2766_f908d2cf7ec03192820bfef05797211c.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
FUZZY β −IRRESOLUTE FUNCTIONS AND FUZZY β −COMPACT SPACES IN FUZZIFYING TOPOLOGY
O. R.
SAYED
M.
AZAB ABD-ALLAH
In this paper the concepts of fuzzifying β − irresolute functions and fuzzifying β − compactspaces are characterized in terms of fuzzifying β − open sets and some of their properties are discussed.
Lukasiewicz logic
fuzzifying topology
β − irresoluteness
fuzzifying compactness
β − compactness
2006
12
28
297
314
http://ijsts.shirazu.ac.ir/article_2770_1914b4f628456398a7fcf535978c484c.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
NETWORK OPTIMIZATION WITH PIECEWISE LINEAR CONVEX COSTS
S.
KETABI
The problem of finding the minimum cost multi-commodity flow in an undirected and completenetwork is studied when the link costs are piecewise linear and convex. The arc-path model and overflowmodel are presented to formulate the problem. The results suggest that the new overflow model outperformsthe classical arc-path model for this problem. The classical revised simplex, Frank and Wolf and a heuristicmethod are compared for the problem.
Multi-commodity network flow problem
piecewise linear and convex costs
Arc-path Model
Overflow
Model
Frank and Wolfe Method
2006
12
28
315
323
http://ijsts.shirazu.ac.ir/article_2771_6002b5bb53510cdb0aa0a5aae56fab6f.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
BRAIDING FROM 2-GROUPS TO 2-GROUPOIDS
E.
ULUALAN
We give the concept of ‘braiding’ for 2-groupoids, and we show that this structure is equivalent tobraided regular, crossed modules.
Braided crossed modules
cat-groups
internal category
monoidal category
2006
12
28
325
341
http://ijsts.shirazu.ac.ir/article_2772_49fa4797bc2e9f7fd3d043c0c05b65a7.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
SEMI-ANALYTICAL SOLUTION OF STABILITY OF COMPOSITE ORTHOTROPIC CYLINDRICAL SHELLS UNDERTIME DEPENDENT A-PERIODIC AXIALCOMPRESSIVE LOAD
H.
SOFIYEV
AL. H.
SOFIYEV
E.
YUSUFOGLU
Z.
KARACA
In this study, the stability problem of a circular orthotropic cylindrical shell under the effect of anaxial compression varying with a power function of time is considered. At first, the modified Donnell typedynamic stability and compatibility equations are obtained using Love’s shell theory. Applying the Galerkinmethod and Rayleigh-Ritz variational techniques to these equations and taking the large values of loadingparameters into consideration, analytics are obtained for critical parameter values. The results show thatcritical parameters are affected by loading parameters variations, ratio of the Young’s moduli variations,radius to thickness variations and the power of time in the axial compression expression variations.Comparing results with those in the literature validates the present analysis.
orthotropic material
cylindrical shell
dynamic critical axial load
dynamic factor
2006
12
28
343
347
http://ijsts.shirazu.ac.ir/article_2773_64b120ae53abfdb6bdc3f7f69c4963f4.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
REGRESSION ANALYSIS IN MARKOV CHAIN
A. Y.
ALAMUTI
R.
MESHKANI
In a finite stationary Markov chain, transition probabilities may depend on some explanatoryvariables. A similar problem has been considered here. The corresponding posteriors are derived andinferences are done using these posteriors. Finally, the procedure is illustrated with a real example.
Bayes
Empirical Bayes
estimation
Markov chain
maximum likelihood
Regression
transition
probability matrix
2006
12
28
349
354
http://ijsts.shirazu.ac.ir/article_2774_087e665a3f96c6b1a75ad8e9d51a35a1.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
TOPOLOGICAL RING-GROUPOIDS AND LIFTINGS
A.
FATIH OZCAN
I.
ICEN
M.
HABIL GURSOY
We prove that the set of homotopy classes of the paths in a topological ring is a topological ringobject (called topological ring-groupoid). Let p : X → X be a covering map and let X be a topological ring.We define a category UTRCov(X) of coverings of X in which both X and X have universal coverings, and acategory UTRGdCov( π1X ) of coverings of topological ring-groupoid π1X , in which X and R0 = X haveuniversal coverings, and then prove the equivalence of these categories. We also prove that the topologicalring structure of a topological ring-groupoid lifts to a universal topological covering groupoid.
Fundamental groupoids
topological coverings
topological ring-groupoids
2006
12
28
355
362
http://ijsts.shirazu.ac.ir/article_2775_f612489b5f4ee6a241d045d959f7d698.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
SOME MAXIMAL INEQUALITIES FOR RANDOM VARIABLES AND APPLICATIONS
M.
AMINI
A.
BOZORGNIA
In this paper, we extend some famous maximal inequalities and obtain strong laws of largenumbers for arbitrary random variables by use of these inequalities and martingale techniques.
Kolmogorove's inequality
Hajek-Renyi inequality
Strong law of large numbers
Martingale
2006
12
28
363
367
http://ijsts.shirazu.ac.ir/article_2776_0f0da3aaca17de5d99128ef36e67b026.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2006
30
3
EXISTENCE OF THREE SOLUTIONS FOR THE DIRICHLET PROBLEM INVOLVING THE P-LAPLACIAN AND MINIMAX INEQUALITY FOR RELEVANT FUNCTIONALS
G. A.
AFROUZI
S.
HEIDARKHANI
In this paper, we establish some results on the existence of at least three weak solutions for aDirichlet problem involving p-Laplacian using a variational approach.
Dirichlet problem
critical point
three solutions
multiplicity results
minimax inequality
2006
12
28
369
374
http://ijsts.shirazu.ac.ir/article_2777_1936b66f5699ec9bb6108332b0ea7f01.pdf