Sharif Digital Repository

The purpose of this study is providing a framework for the evaluation of process and content of development programs and evaluating the fourth and fifth law development program of Iran. Policy evaluation is one the most important measures in the policy cycle and is implemented with the purpose of learning from the results of stage. Given the wide dimensions of policy making, achieving a model for evaluating policy is faced with many complexities. In this study with reviewing previous experiences in the field of policy evaluation, an integrated model for evaluating policy, is presented from two main aspects of the process and the content and then with using this model, the Fourth Program and... 

The sub-equation method is implemented to construct exact solutions for the conformable perturbed nonlinear Schrödinger equation. In this paper, we consider three different types of nonlinear perturbations: The quadratic-cubic law, the quadratic-quartic-quintic law, and the cubic-quintic-septic law. The properties of the conformable derivative are discussed and applied with the help of a suitable wave transform that converts the governing model to a nonlinear ordinary differential equation. Furthermore, the order of the expected polynomial-type solution is obtained using the homogeneous balancing approach. Dark and singular soliton solutions are derived. © 2022 World Scientific Publishing... 

A modification to the control law presented in [Y. Lei, W. Xu, H. Zheng, Synchronization of two chaotic nonlinear gyros using active control, Phys. Lett. A 343 (2005) 153] is proposed. © 2007 Elsevier B.V. All rights reserved  

In this paper we analyze the relationship between entropy and information in the context of the mixing process of two identical ideal gases. We will argue that entropy has a special information-based feature that is enfolded in the statistical entropy, but the second law does not include it directly. Therefore, in some given processes in thermodynamics where there is no matter and energy interaction between the system and the environment, the state of the system may go toward a situation of lower probability to increase the observer's information about the environment. This is a kind of information-based interaction in which the total entropy is not constrained by the second law  

The objective of this paper is to provide optimization of falling film LiBr solution on a horizontal single tube based on minimization of entropy generation. Flow regime is considered to be laminar. The effect of boiling has been ignored and wall temperature is constant. Velocity, temperature and concentration distributions are numerically determined and dimensionless correlations are obtained to predict the average heat transfer coefficient and average evaporation factor on the horizontal tube. Thermodynamic imperfection due to passing lithium bromide solution is attributed to nonisothermal heat transfer; fluid flow friction and mass transfer irreversibility. Scale analysis shows that the... 

We introduce a new aspect of the notion of obligation inspired from the Islamic legal system. We then construct a dynamic deontic logic to model this notion of obligation. A semantics for this logic is introduced, and then its soundness and completeness theorems with respect to this semantics are proved. © 2022, Springer Nature Switzerland AG  

Sedimentation of particles can undermine the uniformity of the product in the manufacture of the particle-filled composites. An adequate mathematical description of the sedimentation process could be helpful for providing necessary information concerning the dominant parameters and can give an insight for the process designer to prevent such an undesirable phenomenon in composite production. The present article deals with the mathematical modeling of settling particles during curing of polymer matrix composites. The sedimentation process is described by the mass conservation law for particles. Since the viscosity of the suspending polymer increases as a result of curing process, a new model... 

The well-known ant colony optimization meta-heuristic is applied to design a new command to line-of-sight guidance law. In this regard, the lately developed continuous ant colony system is used to optimize the parameters of a pre-constructed fuzzy sliding mode controller. The performance of the resulting guidance law is evaluated at different engagement scenarios. © Springer-Verlag Berlin Heidelberg 2005  

The problem of finding a lost target in a noisy environment by a group of flying vehicles is studied in this article. The developed cooperative search algorithm that is decentrally applied on the flying vehicles is a combination of searching guidance and neighborhood laws. The searching guidance law generates an acceleration command to direct each flying vehicle to the position of the lost target. The command is generated based on the information gathered by those flying vehicles that are categorized as neighbors by the neighborhood law. The neighborhood law specifies the sharing network between the flying vehicles for intelligent cooperation. Various neighborhood laws are introduced for... 

In this study, exergy analysis and second law efficiency of gas heaters with reactive combustion processes are considered. The reactive combustion of natural gas is modeled via a chain of eight chemical reactions along with first and second law of thermodynamics. The main constitutional elements react in combustion chamber is considered at constant pressure and temperature of the basic elements hydrogen, carbon, oxygen, and nitrogen from the fuel and air. Heat transfer is modeled assuming free convection and radiation mechanisms from gas heater outer surfaces. The governed equations were solved using Engineering Equation Solver (EES) software tool. Results of this study reveal that... 

Consider a binary-input memoryless outputsymmetric channel W. Such a channel has a capacity, call it I (W), and for any R < I (W) and strictly positive constant Pewe know that we can construct a coding scheme that allows transmission at rate R with an error probability not exceeding Pe. Assume now that we let the rate R tend to I (W) and we ask how we have to scale the blocklength N in order to keep the error probability fixed to Pe. We refer to this as the finite-length scaling behavior. This question was addressed by Strassen as well as Polyanskiy, Poor, and Verdu, and the result is that N must grow at least as the square of the reciprocal of I (W)- R. Polar codes are optimal in the sense... 

An improved progressive preconditioning method for analyzing steady inviscid and laminar flows around fully wetted and sheet-cavitating hydrofoils is presented. The preconditioning matrix is adapted automatically from the pressure and/or velocity flow-field by a power-law relation. The cavitating calculations are based on a single fluid approach. In this approach, the liquid/vapour mixture is treated as a homogeneous fluid whose density is controlled by a barotropic state law. This physical model is integrated with a numerical resolution derived from the cell-centered Jameson's finite volume algorithm. The stabilization is achieved via the second-and fourth-order artificial dissipation... 

We introduce a definition of the notion of compressibility for infinite deterministic and i.i.d. random sequences which is based on the asymptotic behavior of truncated subsequences. For this purpose, we use asymptotic results regarding the distribution of order statistics for heavy-tail distributions and their link with α -stable laws for 1<α<2. In many cases, our proposed definition of compressibility coincides with intuition. In particular, we prove that heavy-tail (polynomial decaying) distributions fulfill the requirements of compressibility. On the other hand, exponential decaying distributions like Laplace and Gaussian do not. The results are such that two compressible distributions... 

In this study a more precise formulation of electrical capacitance for a cylindrical capacitive sensor is reported. By using different theoretical models such as Coulomb law, Gauss law and Laplace equation the electrical capacitance is calculated. Based on the given models the relation between the capacitance and the geometrical parameters (e.g., cylindrical length) is formulated and by using suitable software capacitance variation is computed and compared for different methods. In Coulomb method, the electrical potential is first solved numerically by using Mathematica and then the electrical capacitance is computed. It is found that the active capacitor length is crucial parameter in the... 

In this paper, flow of multi-component two-phase fluids in highly heterogeneous anisotropic two-dimensional porous media is studied using computational methods suitable for unstructured triangular and/or quadrilateral grids. The physical model accounts for miscibility and compressibility of fluids while gravity and capillary effects are neglected. The governing equations consist of a pressure equation together with a system of mass conservation equations. For solving pressure equation, a new method called Control Volume Distributed Finite Element Method (CVDFEM) is introduced which uses Control Volume Distributed (CVD) vertex-centered grids. It is shown that the proposed method is able to... 

Purpose: This paper aims to numerically study the compositional flow of two- and three-phase fluids in one-dimensional porous media and to make a comparison between several upwind and central numerical schemes. Design/methodology/approach: Implicit pressure explicit composition (IMPEC) procedure is used for discretization of governing equations. The pressure equation is solved implicitly, whereas the mass conservation equations are solved explicitly using different upwind (UPW) and central (CEN) numerical schemes. These include classical upwind (UPW-CLS), flux-based decomposition upwind (UPW-FLX), variable-based decomposition upwind (UPW-VAR), Roe’s upwind (UPW-ROE), local Lax–Friedrichs... 

In this study the first and the second laws of thermodynamics are evaluated for a single effect absorption chiller. Entropy generation and COP are selected as the objective functions and their variations are studied by varying the generator temperature for various condensing temperatures. For this purpose, the enthalpy and the entropy data of the super-heated steam, saturated steam and the saturated water are formulated in the mathematical equations. Also to provide the required steam of generator, prime mover in the form of internal combustion engine is applied and its partial load conditions are analyzed. A residential tower is considered as the case study for selecting the proper prime...