Sharif Digital Repository

Due to major problems induced by delamination in laminated composites, functionally-graded materials (FGM) have been put to growing use in recent years. In the present research, dynamic stability of FGM cylindrical shells under axial follower loads is addressed. Loading was considered in three forms: concentrated (Beck’s problem), uniformly-distributed (Leipholz’s problem), and linearly-distributed (Hauger’s problem). In order to derive the governing equations, Love’s hypotheses and First-order Shear Theory (FST) were used. To solve the equations, polynomial mode shapes were used to approximate the displacements, and the extended Galerkin method was applied. The problem was solved for mild... 

Developing an android application from scratch is a time-consuming and expensive process, but modifying an existing and similar application is much easier. Modifying an android application, which is called repackaging, is done for different purposes. Cracking non-free android applications, modifying advertising libraries code, adding malicious payload to benign ones and redistributing known malwares are some of the important purposes. Existing methods for confronting android application repackaging can be divided into three categories: 1) based on comparing with the original application, 2) based on changing the original application, 3) based on changing the android platform. Methods in the... 

Think of an Alpine hiker who because of avalanche and a blinding blizzard, is stranded on a desolate, mountain path facing a chasm. The hiker cannot return the way he came because of the avalanche, yet, if he stays where he is, he will freeze as the temperature plummets. The hiker’s only real hope is to jump the chasm. Knowing that exertion generally follows belief, the hiker realizes that his attempt will be half-hearted, diminishing his chance of survival, unless he brings himself to the belief that he can make the jump. In circumstances like these, one is clearly justified both in forming beliefs motivated by pragmatic reasons, and in suppressing beliefs (I cannot make the jump) motivated... 

The thesis at hand provides a comparative study of Kantian and Fichtean ethics. In the course of this study, the ethical theory of these philosophers will be analyzed through three stages of “Foundation of Ethics,” “System of Ethics,” and “Application of Ethics”: Foundation of Ethics seeks out human will as the sole possible ground for ethical theory of both Kant and Fichte; System of Ethics follows the endeavors of the two thinkers in deducing concept of ethics from this sole ground; and lastly, Application of Ethics introduces the ethical thoughts resulting from a Fichtean account of ethics. This thesis is mostly based upon studies of Allen W. Wood of the ethical thoughts of Kant and... 

In this thesis a smart anticorrosive pH-responsive coat was developed with layer by layer (LbL) technique in the assembly of SiO2/CTAB/PSS/HMTA/PSS/PEI/PSS. SiO2 nanoparticles were prepared from Matland Company (Iran) with average size of 24 nm. At first, the corrosion inhibition of HMTA for API 5L Grade B steel in 3.5 wt.% NaCl solution was investigated. Tafel polarization technique showed the optimum concentration of HMTA was 0.08 M with 92% corrosion inhibition efficiency as the morphology of coverage and adsorption on the steel surface was confirmed by SEM and EDS. AFM results showed the roughness of the surface decreased from 241 nm to 56 nm that is attributed to HMTA adsorption on the... 

In recent years, sparse representation has had a variety of applications in computer vision such as noise reduction, image reconstruction, classification and dimension reduction. In this project, we aim to provide a method of matching the keypoints obtained from the Scale Invariant feature Transform (SIFT) algorithm. In this algorithm is used descriptor instead of intensity . The proposed method, first, extracts the salient points from the images and learns a dictionary-based descriptors corresponding to the points. Then, using the dictionary, it obtains the sparse coefficients for each salient point by which, it determines the correspondence of the salient points in the two images using SVD... 

The search for an empirically proven quantum theory of gravity is one of the greatest open problems of fundamental physics. Obstacles are formal and conceptual in nature. Our goal is to find a theory that somehow unites general relativity (Einstein's classical field gravity theory) and quantum field theory. In this research work, the problem of quantum gravity and the reason for its importance are investigated, as well as the proposed solutions; and what philosophical issues do these approaches and the issue itself create. Research has been carefully selected to remain managed in terms of size and content, however, some basic formalism is introduced to enter physics and the philosophy of... 

By “Analysis of Epistemological Justification of Inference to the Best Explanation (IBE)” I mean to examine whether the IBE argument can increase the probability of the truth of belief to the outcome of the argument or not. According to the Strong Version of IBE, this increase shows that the best explanation is more likely to be true, whereas according to the Weak Version the best explanation is more probable than its available rivals. The most influential arguments against these positions are: (1) The bad lot objection (BLO) according to which the idea that the best available explanations will be more likely to be true, presupposes that the truth is already more likely to be found among... 

Michael Zimmerman in his book Living with Uncertainty has objected to two views of moral obligation, namely objective and subjective view. Two overcome these problems he suggests a third view which he calls prospective view and tells us that our moral obligation is determined by the prospection that each of our choices give us. In this thesis first I review Zimmerman’s objections to objective and subjective view. Then I try to suggest a solution for the objective view  

This dissertation consists of three chapters. In the first chapter, a description of formation of Darwin's theory of Evolution is expressed. After that, the process of formation of modern theory of Evolution, along with an explanation of the theory of evolution and the evidence for it was mentioned. In the second season, which is responsible for the scientific study of the theory, at some point the evidence of this theory has been reviewed. After that, some of the challenges raised against this theory have been studied. The major scientific challenges described in this chapter is based on recent advances made in biology, based on that, the mechanism of theory can’t explain the complex... 

In Naming and Necessity and Identity and Necessity, Kripke convinced many that there are necessary propositions which are knowable only a posteriori. Kripke’s examples of these propositions can be placed into three categories: 1) Some mathematical propositions like Goldbach’s conjecture (the conjecture that every even integer greater than 2 can be expressed as the sum of two primes) 2) Scientific truths like “Water is H2O”, “Gold has the atomic number 79”, etc. 3) Identity statements flanked on both sides with proper names; like “Hesperus is Phosphorus”, “Cicero is Tully” and the like (in the rest of this article, these three categories will be called, respectively, the first, the second and...