there are many approaches for solving variety combinatorial optimization problems (np-compelete) that devided to exact solutions and approximate solutions. exact methods can only be used for very small size instances due to their expontional search space. for real-world problems, we have to employ approximate methods such as evolutionary algorithms (eas) that find a near-optimal solution in a r...

reinsurance is widely recognized as an important instrument in the capital management of an insurance company as well as its risk management tool. this thesis is intended to determine premium rates for different types of reinsurance policies. also, given the fact that the reinsurance coverage of every company depends upon its reserves, so different types of reserves and the method of their calc...

one of the most important factors in study of project’s , is the study of environmental opportunities factors the permanent study of environmental opportunity factors . the study of permanent environmental changing and knowing golden threats’ cooperate with possible threats and at the result in structure forming and future skeleton of organization has a vital effects . the petrochemical industr...

drought is transient phenomenon , slow , repetitive and integral part of the climate of each region. drought begins with a substantial reduction in precipitation over the long-term average rainfall and over time, reduced soil moisture and surface and ground water resources will continue to decrease. this phenomenon is the most important in bakhtegan basin because of its importance in strategic ...

peace and national security protection and ironic solving of international conflicts become the preliminary foundation of the united nations charter and had been considered as the main responsibilities of the security council, after world war ii and the establishment of united nations organization. therefore, the security council enables to analyze every kind of conflicts and challenges which ...

magnetic resonance imaging (mri) is a notable medical imaging technique that makes of phenomenon of nuclear magnetic resonance. because of the resolution and the technology being harmless, mri has considered as the most desirable imaging technique in clinical applications. the visual quality of mri plays an important role in accuracy of medical delineations that can be seriously degraded by exi...

according to webster and wind (1972) and anderson et al (1987), “organizational buying is a complex process and involves many people from different functional areas, multiple goals and potentially conflicting decision criteria. moreover, the customers of today are also more knowledgeable and selective when making their purchasing decisions. since a key to organizational survival is the retentio...

one of the most important number sequences in mathematics is fibonacci sequence. fibonacci sequence except for mathematics is applied to other branches of science such as physics and arts. in fact, between anesthetics and this sequence there exists a wonderful relation. fibonacci sequence has an importance characteristic which is the golden number. in this thesis, the golden number is observed ...

abstract nowadays, industries cannot play a crucial role in national and international competitions. the tourism industry is no exception. tourism industry development as the most important economic sector and income generation is one of the key challenges of economic development in the world. therefore, countries were successful that take advantage of the capabilities of tourism sector using ...

abstract: in the paper of black and scholes (1973) a closed form solution for the price of a european option is derived . as extension to the black and scholes model with constant volatility, option pricing model with time varying volatility have been suggested within the frame work of generalized autoregressive conditional heteroskedasticity (garch) . these processes can explain a number of em...