Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
COMBINED HEAT AND MASS TRANSFER IN MHD FREE CONVECTION FROM A WEDGE WITH OHMIC HEATING AND VISCOUS DISSIPATION IN THE PRESENCE OF SUCTION OR INJECTION
151
162
EN
R.
KANDASAMY
Centre for Science Studies, University of Tun Hussein Onn, Malaysia,
86400 Parit Raja, Batu Pahat Johor, Malaysia
kandan_kkk@yahoo.co
I.
HASHIM
School of Mathematical Sciences, University of Kebangsaan, Malaysia,
43600 UKM Bangi Selangor, Malaysia
A. B.
KHAMIS
Centre for Science Studies, University of Tun Hussein Onn, Malaysia,
86400 Parit Raja, Batu Pahat Johor, Malaysia
I.
MUHAIMIN
Centre for Science Studies, University of Tun Hussein Onn, Malaysia,
86400 Parit Raja, Batu Pahat Johor, Malaysia
10.22099/ijsts.2007.2324
The problem of combined heat and mass transfer of an electrically conducting fluid in MHDnatural convection adjacent to a vertical surface is analyzed, taking into account the effects of Ohmic heatingin the presence of suction or injection. An approximate numerical solution for the steady laminar boundarylayerflow over a wall of the wedge in the presence of species concentration and mass diffusion has beenobtained by solving the governing equations using the numerical technique. The fluid is assumed to beviscous and incompressible. Numerical calculations are carried out for different values of dimensionlessparameters and an analysis of the results obtained shows that the flow field is influenced appreciably by themagnetic effect, the buoyancy ratio between species and thermal diffusion and suction/injection at the wallsurface. Effects of these major parameters on transport behaviors are investigated methodically and typicalresults are illustrated to reveal the tendency of the solutions. Representative results are presented for thevelocity, temperature, and concentration distributions, as well as the local skin-friction coefficient and skinfriction.
Buoyancy ratio,Ohmic heating,Boussinesq fluid,MHD boundary layer flow and suction/injection at
the wall of the wedge
http://ijsts.shirazu.ac.ir/article_2324.html
http://ijsts.shirazu.ac.ir/article_2324_f85ca468fa7afed222d5fef73f4909a2.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
ON PROBLEMS REDUCING TO THE GOURSAT PROBLEM FOR A FOURTH ORDER EQUATION
163
170
EN
A.
MAHER
Department of Mathematics, Faculty of Science, Assiut University, 71516, Egypt
a_maher69@yahoo.com
YE. A.
UTKINA
Department of Differential Equations, Kazan State University,
18 Kremlyovskaya St., Kazan, 420008, Russia
10.22099/ijsts.2007.2325
In this paper, we investigate some problems which can be reduced to the Goursat problem for afourth order equation. Some results and theorems are given concerning the existence and uniqence for thesolution of the suggested problem.
Fourth order of partial differential equations,goursat problem
http://ijsts.shirazu.ac.ir/article_2325.html
http://ijsts.shirazu.ac.ir/article_2325_67776a597b75725198c49b9e4d70f7d9.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
HIGH SPIN STATES IN 191OS
171
175
EN
S.
MOHAMMADI
Physics Department, Payam Noor University, Mashhad 91735, I. R. of Iran
mohammadi@pnu.ac.ir
ZS.
PODOLYAK
Department of Physics, University of Surrey, Guildford, GU2 7XH, UK
10.22099/ijsts.2007.2326
High spin states in the neutron rich nucleus 191Os has been populated for the first time using the82Se+192Os deep-inelastic reaction at 460 MeV beam energy using the ALPI accelerators at the LaboratoryNazionali di Legnaro, Italy. High fold γ-γ coincidences were acquired with the 4π spectrometer GASPdetector array, consisting of 40 Compton-suppressed, large-volume germanium detectors with an inner ballconsisting of 80 BGO crystals acting as a multiplicity filter and a total-energy spectrometer. The newdiscovered level scheme is extended up to spin 19/2+. The observed structure is interpreted as fragments of arotational band built on single neutron configuration {11/2+ [615]} according to a Nilsson deformed shellmodel.
Deep-inelastic Reaction,Rotational Band,High Spin States,Deformed Shell Model,Gamma-gamma
Coincidences
http://ijsts.shirazu.ac.ir/article_2326.html
http://ijsts.shirazu.ac.ir/article_2326_9f20d131682480774cd48e1443251f9f.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
ON THE HELICES IN THE GALILEAN SPACE G3
177
181
EN
A. O.
OGRENMIS
Department of Mathematics, Firat University, 23119, Elazig, Turkey
aogrenmis@firat.edu.tr
E.
ERGUT
Department of Mathematics, Firat University, 23119, Elazig, Turkey
M.
BEKTAS
Department of Mathematics, Firat University, 23119, Elazig, Turkey
10.22099/ijsts.2007.2327
T. Ikawa obtained an ordinary differential equation for the circular helix. Recently, the helix havebeen investigated by many differential geometers such as T. Ikawa, H. Balgetir, M. Bektas, M. Ergut, N.Ekmekci and H. H. Hacısalihoglu. In this paper, making use of this author’s methods, we obtainedcharacterizations of helix for a curve with respect to the Frenet frame in 3-dimensional Galilean space G3.
Galilean Space,Helix
http://ijsts.shirazu.ac.ir/article_2327.html
http://ijsts.shirazu.ac.ir/article_2327_b01dbc7305fb6076018322b51bdadd31.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
DOUBLE SEQUENCE SPACES DEFINED BY ORLICZ FUNCTIONS
183
188
EN
E.
SAVAS
Istanbul Ticaret University, Department of Mathematics, Uskudar, Istanbul, Turkey
ekremsavas@yahoo.com & esavas@iticu.edu.tr
R. F.
PATTERSON
University of North Florida, Building 11 Jacksonville, Florida 32224, USA
rpatters@unf.edu
10.22099/ijsts.2007.2328
In this paper we introduce some new double sequence spaces using the Orlicz function andexamine some properties of the resulting sequence spaces.
Double sequences,P-convergent,Orlicz functions
http://ijsts.shirazu.ac.ir/article_2328.html
http://ijsts.shirazu.ac.ir/article_2328_6f2c9f3812a99498fab81db1a379565b.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
SEQUENTIAL ESTIMATION IN A SUBCLASS OF EXPONENTIAL FAMILY UNDER WEIGHTED SQUARED ERROR LOSS
189
197
EN
N.
NEMATOLLAHI
Department of Statistics, Faculty of Economics, Allameh Tabataba'i University, Tehran, I. R. of Iran
nematollahi@atu.ac.ir
M.
JAFARI JOZANI
Department of Statistics, Faculty of Economics, Allameh Tabataba'i University, Tehran, I. R. of Iran
N.
MAHLOOJI
Department of Statistics, Faculty of Economics, Allameh Tabataba'i University, Tehran, I. R. of Iran
10.22099/ijsts.2007.2329
In a subclass of the scale-parameter exponential family, we consider the sequential pointestimation of a function of the scale parameter under the loss function given as the sum of the weightedsquared error loss and a linear cost. For a fully sequential sampling scheme, second order expansions areobtained for the expected sample size as well as for the regret of the procedure. The former researches onGamma and Exponential distributions can be deduced from our general results.
Sequential estimation,stopping rule,regret analysis,exponential family,transformed chi-square
distribution
http://ijsts.shirazu.ac.ir/article_2329.html
http://ijsts.shirazu.ac.ir/article_2329_ef4dc04839d1c9f19b144aa44df81031.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
MINIMIZING LOSS PROBABILITY IN QUEUING SYSTEMS WITH HETEROGENEOUS SERVERS
199
206
EN
V.
SAGLAM
Department of Statistic, Faculty of Arts and Sciences, Ondokuz
Mayis University, Kurupelit, 55139-Samsun, Turkey,
vsaglam@omu.edu.tr
A.
SHAHBAZOV
Department of Statistic, Faculty of Arts and Sciences, Ondokuz
Mayis University, Kurupelit, 55139-Samsun, Turkey
10.22099/ijsts.2007.2330
The probability of losing a customer in M/G/n/0 and GI/M/n/0 loss queuing systems withheterogeneous servers is minimized. The first system uses a queue discipline in which a customer who arriveswhen there are free servers chooses any one of them with equal probability, but is lost otherwise. Providedthat the sum of the servers rates are fixed, loss probability in this system attains minimum value when all theservice rates are equal. The second system uses queue discipline, in which a customer who enters into thesystem is assigned to the server with the lowest number. Loss probability in this system takes the minimumvalue in the case when the fastest server rule is used in which an incoming customer is served by the freeserver with the shortest mean service time. If the mean of the arrival distribution is fixed, then loss probabilityis minimized by deterministic arrival distribution
Service rate,Erlang’s loss formula,heterogeneous servers,loss probability,recurrent input,exponential
server,overflow distribution
http://ijsts.shirazu.ac.ir/article_2330.html
http://ijsts.shirazu.ac.ir/article_2330_6901ed3bf3527b64512d59331e0f5239.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
STEINER FORMULA AND HOLDITCH-TYPE THEOREMS FOR HOMOTHETIC LORENTZIAN MOTIONS
207
212
EN
S.
YUCE
Yıldız Technical University, Faculty of Arts and Science, Department of Mathematics, Esenler, 34210,
Istanbul, Turkey,
sayuce@yildiz.edu.tr
N.
KURUOGLU
University of Bahcesehir, Faculty of Arts and Science, Department of
Mathematics and Computer Sciences, Besiktas 34100, Istanbul, Turkey
10.22099/ijsts.2007.2331
The present paper is concerned with the generalization of the Holditch Theorem under oneparameterhomothetic motion on Lorentzian planes. In this paper, for the homothetic Lorentzian motion, weexpressed the Steiner formula. Furthermore, we present the Holditch-Type Theorems.
Holditch Theorem,Steiner formula,lorentzian plane,homothetic motion
http://ijsts.shirazu.ac.ir/article_2331.html
http://ijsts.shirazu.ac.ir/article_2331_e2decd10f598924fc8320c13325124c7.pdf
Shiraz University
Iranian Journal of Science and Technology (Sciences)
1028-6276
31
2
2007
08
11
A BOUNDARY INTEGRAL MODEL FOR SIMULATING SPILLING BREAKERS
213
217
EN
S. A.
AZARMSA
Faculty of Marine Sciences, Tarbiat Modares University, Tehran, I. R. of Iran
azarmsaa@modares.ac.ir,
10.22099/ijsts.2007.2332
A boundary integral method is used to simulate spilling breakers. The bottom is also included inthe introduced closed boundary and the problem is directly solved in the physical plane. The method has beenshown to be remarkably stable, and no numerical instability has occurred in any of the calculations. Theresults reveal that both the momentum and total energy are almost constant in time during the simulationperiod. As a result, the breaking process of a spilling breaker is fairly well simulated.
Breaking waves,numerical simulation,spilling,Cauchy’s integral theorem
http://ijsts.shirazu.ac.ir/article_2332.html
http://ijsts.shirazu.ac.ir/article_2332_e1952cb184e26c8f0bdeb548cb62fafb.pdf