2018-01-22T05:52:21Z
http://ijsts.shirazu.ac.ir/?_action=export&rf=summon&issue=462
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
WEIGHTED STATISTICAL CONVERGENCE
V.
KARAKAYA
T. A.
CHISHTI
In this paper, the notion of N, pn - summability to generalize the concept of statisticalconvergence is used. We call this new method weighted statistically convergence. We also establish itsrelationship with statistical convergence, C,1-summability and strong n N, p -summability.
Norlund-type means
weighted statistical convergence
sequence spaces
Cesaro summability
2009
09
13
219
223
http://ijsts.shirazu.ac.ir/article_2217_176bc8128ea526368e2bcc429ae97a23.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
ESTIMATION OF GALAXY AGE BY MODIFIED MEYER AND SHRAMM NUCLEOSYNTHESIS MODEL
M. R.
ESKANDARI
M.
BAHADORAN
The independent model used by Meyer and Schramm (here after M&S) for determining the age ofelements (chemical evolution) is extended. Using new and extended definitions and including parametersignored by M&S, the galactic evolution equations are solved to determine the total duration ofnucleosynthesis,T. To be able to calculate the t T (mean age time for formation of elements to total duration of nucleosynthesis ratio), one event age, max ij , and r(i, j) are determined using approximation relating r(i, j) to the former value r(i, j). For Th/U pair, constraint on t T becomes 0.43 t T 0.61 and the age of the galaxy is obtained as 12.5 23.0 Gal Gyr T Gyr , reducing the variation considerablycompared to M&S formalism ( 8.7Gyr TGal 28.1 Gyr ). The range of constraints for the age of theuniverse is shorter than the M&S and our modifications on the model have reduced the interval for galaxy age 83% and close to being concordant with other available methods.
Nucleosynthesis
cosmochronology
age of universe
independent model
galaxy evolution
chronometric pairs
abundances
2009
09
13
225
233
http://ijsts.shirazu.ac.ir/article_2218_4aecaa13eb3d2693ffdecfc3801786e7.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
A GENERALIZED SUMMABILITY FACTOR THEOREM FOR ABSOLUTE SUMMABILITY AND QUASI POWER INCREASING SEQUENCES
E.
SAVAS
The object of this paper is to establish a summability factor theorem for summabilityA, , k 1 k where A is the lower triangular matrix with non-negative entries satisfying certain conditions.
Generalized absolute summability
weighted mean matrix
cesaro matrix
summability factor
2009
09
13
235
240
http://ijsts.shirazu.ac.ir/article_2219_e0f8a4bf5159dc19e91050cd5e68a032.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
FINSLER METRICS WITH SPECIAL LANDSBERG CURVATURE
A.
TAYEBI
E.
PEYGHAN
In this paper, we study a class of Finsler metrics which contains the class of P-reducible andgeneral relatively isotropic Landsberg metrics, as special cases. We prove that on a compact Finsler manifold,this class of metrics is nothing other than Randers metrics. Finally, we study this class of Finsler metrics withscalar flag curvature and find a condition under which these metrics reduce to Randers metric.
Randers metric
flag curvature
Landsberg metric
P-reducible
2009
09
13
241
248
http://ijsts.shirazu.ac.ir/article_2220_7bbea45db2071e12f2c72620d637da2f.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
COMMON FIXED POINTS OF TWO NONEXPANSIVE MAPPINGS BY A NEW ONE-STEP ITERATION PROCESS
S. H.
KHAN
M.
ABBAS
A. R.
KHAN
We introduce a new one-step iteration process to approximate common fixed points of twononexpansive mappings in Banach spaces and prove weak convergence of the iterative sequence using (i)Opial’s condition and (ii) Kadec-Klee property. Strong convergence theorems are also established in Banachspaces and uniformly convex Banach spaces under the so-called Condition ( A ), which is weaker thancompactness.
One-step Iteration Process
nonexpansive mapping
common fixed point
condition (A) weak and
strong convergence
2009
09
13
249
257
http://ijsts.shirazu.ac.ir/article_2221_9404272f263e0e8a6524fc174aec85fd.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
DESIGN AND CONSTRUCTION OF AN ACCURATE TIMING SINGLE CHANNEL ANALYZER
A.
EZZATPANAH LATIFI
F.
ABBASI DAVANI
M.
SHAHRIARI
A.
SHARGHI IDO
In this paper we discuss an approach to the design and construction of an accurate timing singlechannel analyzer (TSCA) for the timing of pulses over a wide dynamic range. A brief overview of the timingmethods and uncertainty factors as "walk and jitter" and a detailed description of the TSCA circuit are giventogether with some insight into the application and reasons that led us to the design and construction ofconstructed TSCA. The advantages of this instrument are then highlighted and the experimental results arepresented.
Timing Single Channel Analyzer (TSCA)
Constant Fraction Trailing Edge (CFTE)
Lower Level
Discriminator (LLD)
Upper Level Discriminator (ULD)
2009
09
13
259
267
http://ijsts.shirazu.ac.ir/article_2222_bd6af23bc81fcd9e0c8344e7af691c5f.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
ANALYSIS AND OPTIMIZATION OF A FISSION CHAMBER DETECTOR USING MCNP4C AND SRIM MONTE CARLO CODES
K.
HADAD
M.
HASHEMI
In this study, a general theoretical model to foresee and calculate the current-voltagecharacteristics in a plateau zone and the associated efficiency of the neutron detector (sensitivity) is presented. This study is to complete the previous studies in this field. The model also considers electric field distortion resulting from the charge collection effect. The characteristics curve is obtained as a function of fission rate, chamber geometry, and filling gas pressure. The output current at the saturation domain is calculated. The applied voltages about two phenomena, recombination and avalanche, for working the chamber in an ionization zone are an important part of the calculation. In developing the theoretical model, the MCNP code for fission rate, the SRIM code for electron-ion pair and GEANT4 for gamma sensitivity calculations were used.
Fission chamber
MCNP
GEANT4
SRIM
Optimization
2009
09
13
269
276
http://ijsts.shirazu.ac.ir/article_2223_44c462083c6af7fbd79868c8191c0ac6.pdf
Iranian Journal of Science and Technology (Sciences)
Transaction A: Science
1028-6276
1028-6276
2009
33
3
STUDY OF NEUTRON YIELD FOR THE 241Am9Be SOURCE
T.
KAKAVAND
M.
HAJI-SHAFEIEHA
H.
GHAFOURIAN
Beryllium chemical combination has a considerable effect on the design and fabrication of the241Am9Be neutron source. In this investigation the beryllium combinations were studied as a generator ofneutrons with various mass percentage, and the neutron yields were also calculated using the results of theALICE and SRIM codes calculations per unit incident charge. The neutron yields of Beryllium Hydride,Beryllium Carbide, Beryllium Hydroxide, Beryllium Oxide, Beryllium Acetate, Beryllium Acetylacetonateand Beryllium Sulfate were calculated as 4397.992107 , 1511.184107 , 976.609107 , 595.299 107 , 336.163107 , 169.62107 and 149.053107 respectively. Our calculations indicate that, the Beryllium Hydride is a proper material for use in the 241Am9Be neutron source.
Neutron
Beryllium
Americium
ALICE Code
SRIM Code
Neutron Yield
2009
09
13
277
280
http://ijsts.shirazu.ac.ir/article_2224_2386c79e3599fa454583916ce1f0b2bc.pdf