Sharif Digital Repository

Swampland conjectures are set of conditions that must be satisfied in a quantum field theory in order to be compatible with a theory of quantum gravity. These conditions have been deduced from the features of field theories, which are derived from the compactification of the additional dimensions of the string theory. However, it is thought that the mpatibility of these conditions with the theory of quantum gravity is independent of string theory. One of the important reasons is that the swampland conjectures can be obtained by examining the physics of black holes. Black hole is one of the quantum states of any quantum gravity theory. In this thesis, first we will have an overview of the... 

Career Orientations or career choices, can be affected by internal and external factors. External factors are the environmental conditions that the reward and the attractiveness of selecting a career choice are dependent to them. Internal factors include the needs of oneself from his/her job, his/her beliefs and his/her skills and competencies about the job. In this research the internal antecedents of managerial and technical orientations between programmers have been identified. On the other hand the perception of people about the compensation system as an external factor which can affect the mentioned relationships, have been analyzed. It seems that this is the first research which career... 

One of the long-lived problems in the theory of quantum chromo dynamics is the violation of parity (P) and charge-parity (CP) symmetries in strong interactions. The existence of gluon configurations sourcing from topology leads to degeneracy in the vacuum structure of the theory. This phenomenon is realized by the addition of an extra term proportional to the parameter to QCD Lagrangian. Experimental estimates of neutron electric dipole, predicts a very small value for this parameter. There is no verified justification for this discrepancy. Recently at the relativistic heavy ion collider laboratory (RHIC) some experimental evidence has been found which indicates local CP violation in... 

Determinantal processes are a special family of stochastic processes that arise in physics (fermions), random matrices (eigenvalues), and in combinatorics (random spanning trees and non-intersecting paths). These processes have repelling property (points close to each other are chosen with low probability). Because of this repelling property, determinantal processes are approporiat for modeling some physical quantities (e.g. the position of electrons). Their probabilistic structure is described by operators on complex vector spaces and their eigenvalues. Determinantal processes have interesting properties, e.g. number of points in a region is a sum of independent Bernoulli random variables.... 

Performance – based design is a new concept that has been developed in recent years. Given that roof displacement and story drifts determine the performance of the structure during an earthquake, displacement – based design has been considered to be an effective method for performance – based design. However, limiting the maximum displacement would not necessarily lead to a desirable performance; especially in long – duration earthquakes. Thus consecutive loading cycles and the effect of hysteretic energy should be taken into account. Combining displacement – based design with energy principles will lead to a suitable design method. This study presents performance – based plastic design... 

Today, due to increasing electricity consumption and demand, the use of conventional systems such as thermal, hydro and nuclear power plants is not enough to convert energy. Over the past century, scientists have sought to discover new technologies for exploiting different forms of energy and converting them into high-efficiency electrical energy. One of these ways is to use the phenomenon of magnetohydrodynamics (magnetic fluid dynamics) to convert thermal energy directly into electrical energy. Magnetohydrodynamics is a theoretical field that studies the dynamics of fluids with electrical conductivity. Induction magneto-hydrodynamic generators use ionized hot plasma (a quasi-neutral gas of...