AMIRKABIR
Year:2005 | Volume:16 | Issue:62-D|Papers Count:16

Strategic planning techniques have been used at different level of the business, such as firms and corporations for many years. But at the Industry level, one does not find an abundance of strategic planning models. In this paper, with the purpose of developing a strategic planning model for the textile industry, the strategic planning models at the SBU, corporate and national level was reviewed. And their Strength in this respect was considered; as, their weaknesses, shortages and lacks. As a result the Portfolio Strategic Planning Models at the corporation level was selected as a base for developing a model at the industry level, which will develop with combination of some processes of national models and some corrections base on the level change. Finally, we suggested a new conceptual three dimensional framework for Strategic planning at the industry level.    

The effectiveness of Alcalase and Savinase two proteolytic enzymes were evaluated towards the degumming of Iranian silk. The results were compared with the conventional method of silk degumming (soap degumming). Also, efficiency of some parameters such as time, concentration of enzymes, L.R. on degumming of the raw material was studied. In addition, mixture of these enzymes with different ratio were used for silk degumming. The degummed samples were assessed for quality by comparing their weight loss and physical properties (Strength and Elongation). The results obtained show that enzymatic degumming of silk could be a good alternative method for soap degumming, due to introducing better properties the to degummed silk filaments and less consumption of chemicals and energy. Also SEM pictures show the less degradation of the filaments and confirm the results obtained by enzymatic treatment of the raw silk samples. In addition, as enzymes are Eco-friendly products, it would not produce any harmful material in the wastewater of the silk degumming process.  

In this paper, attempts were made to investigate the effect of resin and pigment concentration, pH of bath and also the processing factors of CED (Cathodic Electrodeposition) system such as constant applied voltage, the bath temperature and time of application on the final properties (such as thickness, appearance properties, physical & mechanical properties) of CED coated on the mild steel. The Taguchi L25 design was selected as the DOE model and the results were analyzed accordingly. The results showed that the constant applied voltage is the most decisive factor determining the final properties of CED coat. Pigment and resin concentration do not show a significant effects on the thickness but the optimum composition of these two factors determine the final properties of coated film. Apart from these three factors, pH and temperature have almost the same effect on thickness and final properties of coat. Coating time has the least effect on the final properties of the coat.    

In this paper, the effect of pre-stresses on the dynamic response of large fibre composite plates in the form of lamina and/or symmetric laminates subjected to low velocity transverse impact was studied using analytical procedure. Pre-stresses were considered in the form of tensile and compressive loads which are uni-axial as well as bi-axial types applied to the edges on mid-plane of the plate. Sveklo's contact law for anisotropic bodies was used. The effect of pre-stresses was considered on contact force, contact time and central deflection of the plate. Using the same analytical method, the effect of uni-axial pre-stresses applied along the fibres as well as perpendicular to the fibres and the effect of various ply sequences on the dynamic response of the plate subjected to transverse impact was studied.

Conducting plastic electrodes have been developed and investigated for the vanadium redox flow battery. The results have revealed that, due to damage to electrical contact at interface between the felt/composite polymer substrate, the deactivation of graphite felt/composite electrode after severe anodization is irreversible mainly, It was also found that neither electrochemical oxidation of felt nor physical detachments of the felt layer from its substrate is the main reasons for conductive polymer electrodes deterioration. Actually, the polymer destruction under highly oxidizing overcharge V(V) solution is the real mechanism for conductive polymer electrode deterioration. However, the composite electrodes fabricated in this project have proved to be about 10 and 3 times more stable than Toray and graphite fiber filled SEBS composite electrodes respectively under overcharge condition. These electrodes are thus superior to the commercial electrodes for application in the vanadium redox battery.      

Measurement and monitoring of product characteristics during of production is very important to achieve improvement in product qualities. According to increased rate of machinery speed this issue becomes more important, especially in case of yarn texturing because of high demand of textured textiles. In this investigation, new methods introduced for determination of crimp indices in false twist and knit de knit textured yarns. In false twist textured yarns the box counting and distance fractal dimension used in addition to crimp percentage to achieve good correlation with crimp contraction. The filament's structure at knit de knit textured yarns were very regular and flat, so in this case the crimp percentage can explain the total crimp contraction of this type of yarn. Finally, utilization of fast Fourier Transforms on images of this type of yarns, successfully predicts the frequency and length of crimp waves.      

When computing numerically the solution of a partial differential equation in an unbounded domain usually artificial boundaries are introduced to limit the computational domain. Special boundary conditions are derived at these artificial boundaries to approximate the exact whole-space solution. If the solution of the problem on the bounded domain is equal to the whole-space solution (restricted to the computational domain) these boundary conditions are called transparent boundary conditions (TBCs). This paper discusses the TBCs for general Schrodinger-type pseudo-differential arising from parabolic equation models which have been widely used for one-way wave propagation problems in various application areas, e.g. seismology, optics and plasma physics. Moreover in this paper we will propose a new discrete TBC. The accuracy and relatively lower cpu-time of the new approach is confirmed by the numerical comparisons.      

A class of Finsler metrics are (α,β) -metrics which has many applications in sciences and  technology. One of the problems in Finsler geometry is finding Finsler metrics with constant flag curvature. In this paper after some preliminaries in (α,β) -metrics, we find a sufficient condition for a Finsler metric of type F= α φp(α/β) to be a space of scalar curvature. We also find a necessary and sufficient condition for a Finsler metric of type F= (α+β) 2 / α to be of constant flag curvature. The method of this paper may be useful for developing the navigation problem.  

The main aim of this work is to provide a new variant of Karmakr's algorithm to give a new high performance algorithm for solving linear programming problems. Modification of the new interior point algorithm presents the new parameter which has a great role in faster convergence of the new method comparing other methods presented by Karmarkar [5] and Scherijver [9]. Number of iterations for the successful convergence for problems of different sizes is given. Numerical results show that when we use new parameter in the classical Karmarkar algorithm, the needed number of iterations is less than the iterations for the above two mentioned methods.      

Here the capacity of compact sets in a non-compact Finsler manifold is introduced. We show that it is invariant under conformal mappings. In the other words we prove that; If (M, g) is a non-compact Finsler manifold then the capacity of a compact set in M is invariant under conformal mappings, and also the capacity of a paire of closed subsets of a Finsler manifold is invariant under conformal mappings. Then we construct and study some famous conformal invariant functions which are efficient tools for solving some problems in the case of conformal Riemannian geometry in the large.    

In this paper, first we extend theorem of Goebel-Schoneberg for non-expansive representations of a left amenable semitopological semigroup on a nonempty subset D of a Hilbert space H. Then we state and prove a common absolute fixed point theorem for these semigroups.

Let G be a locally compact abelian group and µ ε M (G) be given. If µ is the product of an invertible and an idempotent measure then the ideal µ * L1 (G) is obviously closed in L1 (G). The problem whether the converse is also true, which was raised by E. Hewitt, has been first studied by I. Glicksberg and later by B. Host and F. Parreau who completely solved it in their impressive paper. Thus µ * L1 (G) is closed in L1 (G) if and only if µ is the product of an invertible and an idempotent measure in M (G). In this paper we study the multipliers with closed range on the weighted group algebra L1 (G, ω). We prove among other things that, the Glicksberg-Host-Parreau theorem for group algebras remain valid for regular weighted group algebras.