مجله ایرانی علوم و تکنولوژی-الف
سال:1392 | دوره: | شماره: |تعداد مقالات:14

Using the Riemann-Liouville fractional differintegral operator, the Lie theory is reformulated. The fractional Poisson bracket over the fractional phase space as 3N state vector is defined to be the fractional Lie derivative. Its properties are outlined and proved. A theorem for the canonicity of the transformation using the exponential operator is proved. The conservation of its generator is proved in a corollary. A Theorem for the inverse fractional canonical mapping is proved. The composite mappings of two successive transformations is defined. The fractional Lie operator and its properties are introduced. Some useful lemmas on this operator are proved. Lie transform depending on a parameter over the fractional phase space is presented and its relations are proved. Two theorems that proved the transformation F= EW Z is completely canonical and is a solution of the Hamiltonian system (30) are given. Recurrence relations are obtained.

The stochastic models for ship heave motion in irregular sea waves based on white and colored noises are examined. For this purpose the deterministic model transfers to stochastic models by adding different noise terms in force and then these models are solved analytically and numerically. Finally an investigation is undertaken to examine the parameter estimation problem of second order stochastic differential equations when some of the measurements are unavailable or missing data. Several simulation results are presented to illustrate the performance of the estimators.

Scattering of an incoming wave train by a discontinuity at the upper surface of the ocean over a uniform porous bottom of finite depth is considered here in the framework of linearized water wave theory. By employing residue calculus method, the reflection and transmission coefficient are obtained. These coefficients are computed numerically for different values of the porosity parameter G and these results are displayed in a number of Figs.

Algebraic frames are generalizations of Fourier transforms on locally compact abelian groups in the sense that the family of vectors forming the frame are replaced by a family of unbounded linear functionals. The paper studies the indexing measure space of the algebraic frames; as the investigation narrows down to the class of lower semiframes, more relations are revealed between the discreteness and the redundancy of the frame family.

In this study, we focused on l/2- Legendre curves and non-l/2 - Legendre curves in 3-dimensional Heisenberg group IN3. Also, we gave some characterizations of these curves.

In this paper, we present the concepts of a fuzzy soft left (right) ideal and fuzzy soft interior ideal over an ordered semigroup S . Some basic results of fuzzy soft left (right) ideals and fuzzy soft interior ideals are investigated and the supported examples are provided. Different classes, regular, intra-regular, and simple ordered semigroups are characterized by means of fuzzy soft left (right) ideals and fuzzy soft interior ideals. It is shown that an ordered semigroup is simple if and only if it is fuzzy soft simple. Furthermore, left (right) regular and intra-regular ordered semigroups are characterized by means of fuzzy soft left (right) ideals and fuzzy soft ideals. 

The concept of G-semihyperring is a generalization of semiring, a generalization of semihyperring and a generalization of G -semiring. Since the theory of ideals plays an important role in the theory of G-semihyperring, in this paper, we will make an intensive study of the notions of Noetherian, Artinian, simple and regular G -semihyperrings. The bulk of this paper is devoted to stating and proving analogues to several theorems in the theory of G-semihyperrings.

In this paper we define (Î-,Î-n q-k)-fuzzy h -sub hemirings(Î-,Î-n q-k)-fuzzy h -ideals, (Î-,Î-n q-k)-fuzzy h -bi-ideals and (Î-,Î-n q-k)-fuzzy h -quasi-ideals. We characterize h -hemiregular and h –intrahemiregular hemirings by the properties of their (Î-,Î-n q-k)-fuzzy h -ideals, (Î-,Î-n q-k)-fuzzy h -bi-ideals and (Î-,Î-n q-k)-fuzzy h -quasi-ideals.

4-Dodecylbenzenesulfonic acid (DBSA) has been shown to be an efficient, mild, green, stable and chemoselective Brfnsted acid catalyst for the synthesis of 1, 1-diacetates (acylals) of aldehydes under solvent-free conditions. The mild condition, eco-friendly, excellent yields, short reaction times and using an easily available, inexpensive and reusable catalyst are important features of this method.

Dust acoustic (DA) solitary waves are investigated in an unmagnetized dusty plasma comprising of fluid warm dust particles and kappa distributed ions. We assume the electron number density to be sufficiently depleted in this fluid model, i.e., ne<<nd . We consider the usual ad hoc damping term, involving the damping rate n due to the dust-neutral collisions; and derived the modified dispersion relation of DA waves. It is found that there is a critical wave number, which should have k>kcrit , otherwise overdamping occurs. The critical value of the wave number increases withn , while it decreases withk . Also, a modified Korteweg-de-Vries (mKdV) equation was derived for description of DA solitary wave. We found that the amplitude, width and velocity of DA solitary waves are modified in the presence of damping term. As the amplitude and velocity of solitary DA wave decreases with t, the width of soliton spreads. Also, it is found that the polarity of soliton changes from positive to negative at special value of k.

Copper Sulphide (Cu2S) thin films at different thicknesses and annealing temperatures were deposited onto glass substrate by vacuum evaporation method. XRD study reveals the phase transformation of Cu2S film at higher thickness. Optical and resistivity study show the phase transformation of the film from Cu2S to CuS when they are annealed at higher temperature. SEM study exhibits the disappearance of large size particles of annealed film. Stability of the film is controlled when the films are prepared at higher thickness. Optical band gap and activation energy for different thickness and various annealing temperatures of Cu2S thin film were calculated and the valuesare reported. Photocurrent enhances with film thickness and heat treatment.

The present survey deals with the floristic study of Dalab Woodlands, located in Manesht and Ghelarang protected area, western Iran. It covers an area of 4335 ha. In total, 224 vascular plant species belonging to 46 families and 156 genera were identified. The largest families are Asteraceae (29 species), Fabaceae (23 species), Poaceae (22 species), and Apiaceae (18 species). Astragalus (13 species), Centaurea (9 species), Onosma (6 species), Bromus (5 species) and Amygdalus (3 species) are the most diverse genera of the region. The life form spectrum includes: hemichryptophytes (36.6 %), therophytes (33 %), cryptophytes (13.8 %), chamaephytes (8.9 %) and phanerophytes (7.6 %). From the chorological point of view, the largest proportion of the flora belongs to the Irano-Turanian (68.7 %) elements. About 22.32 % of the Dalab Woodlands species are endemic to Iran and six rare species including Alrawia bellii, Arum giganteum, Cousinia cylindracea, Echinops kotschyi, Thymbra spicata and Zeugandra iranica are also identified in this region.

The in-situ method of synthesis has been used to isolate oxovanadium(IV) complexes with ligands derived by reaction of benzil with amino acids such as glycine, alanine, serine, cysteine and valine, where template effect of VO+2 cation appears to play an important role. The complexes are characterised by elemental analysis, magnetic moment measurements and spectral (infrared, electronic and electron spin resonance) data. The oxovanadium (IV) complexes are five coordinate, having tetradentate ligand derived from benzil being precursor molecule. The antifungal activities of isolated vanadyl complexes are tested against the fungi Aspergillus flavus and Candida glaberata.

The thermally stimulated discharge (TSDC) current is studied for acrylonitrile butadiene rubber (NBR) loaded with different high abrasion furnace carbon black (HAF). TSDC peak appears only for higher HAF contents >60phr (70 and 80phr of HAF contents), the TSDC spectra consist of a sharp peak corresponding to a peak temperature Tm which is slightly shifted to higher temperature for 70phr loaded NBR samples and to lower temperature for 80phr loaded NBR sample, with poling field (10V/cm to 50V/cm). The activation energy U and relaxation time t for TSDC peak were calculated using the initial rise method. The calculated values of U are nearly constant for sample 70phr and slightly increase for sample 80phr with increasing poling field Ep. The calculated values of t at peak temperature Tm are nearly constant for two samples (70phr & 80phr) with different poling field, whereas the calculated values of relaxation time t at To=300K increased with increase of poling field.