Investigation and evaluation of dust and microstrip phenomena is one of the important values ​​in the management of climate and environmental hazards in the Middle East, especially in the arid, western, southern and central parts of Iran. Methods and plans for studying this phenomenon and its management are of great importance and great value. According to studies on dust phenomena based on pre...

flow in natural river bends is a complex and turbulent phenomenon which affects the scour and sedimentations and causes an irregular bed topography on the bed. for the reason, the flow hydralics and the parameters which affect the flow to be studied and understand. in this study the effect of bed and wall roughness using the software fluent discussed in a sharp 90-degree flume bend with 40.3cm ...

In this study, the changes in the Khorramabad storm in the period of 1952 to 2015 have been investigated. For this purpose, data from meteorological codes 06 and 07 were received from the Meteorological Organization of the country, and after identifying the days of winding with dust storms and calculating their monthly frequency, monthly, seasonal and annual time series were analyzed. In this s...

it is not possible to understand developments of a country’s culture and civilization without knowing his believes and myths. whether it is north or south, east or west, planes or mountains, sahara or deserts, here in iran every corner includes valuable and precious treasures which are known all over the world, and cultural – historical objects which are found here adorn all well known museums...

this dissertation has six chapter and tree appendices. chapter 1 introduces the thesis proposal including description of problem, key questions, hypothesis, backgrounds and review of literature, research objectives, methodology and theoretical concepts (key terms) taken the literature and facilitate an understanding of national security, national interest and turkish- israeli relations concepts...

Dust storms and high winds is a natural process that occurs in everywhere of arid and semi-arid land in the world. The phenomenon of dust is one of the most important consequences of the desertification that cause different damages. The aim of this study was to analyze the occurrence of dust in the city of Bandar Abbas. First, the frequency of monthly and annual dust from 1985-2005, in the city...

any change in the refractive index of a laser active medium can lead to serious degradation of beam quality, laser beam modes, laser performance and variation in the intensity distribution. alteration in the refractive index of laser active medium is especially notable in high power lasers. it is clear that in the laser beam production, the pumping agent induces a great amount of heat which...

Introduction: Climatic components are the vital factors influencing the dust event. It was believed that changes in climate parameters play a crucial role in the occurrence of dust events. Former studies have shown that temperature, rainfall, and wind speed contribute to poor vegetation, providing requirements of dust events. Long-term dust data indicated that climate has a profound effect on d...

Nowadays, remote sensing and GIS technologies are used as a key element in monitoring of land use and vegetation changes. Using this method as one the main sources receiving and updating information on the Earth's surface changes, plays an important role in the management of ecosystems. The present study aims to investigate land use change, vegetation dynamics and trend of Hamoun wetland betwee...

One of the Factors affecting on the trend of changes in dust phenomenon, is the fluctuations of climatic parameters and consequently drought. The purpose of this study was to investigate the trend of changes in Dust Index (DSI) and its relationship with drought indices (SPI and SPEI) in the southern range of Alborz. After of receiving the meteorological codes, seasonally-annually ten years DSI ...