Global warming

The definition of global warming:-Gradual and continuous increase of the average temperature of the Earth's surface and oceans of water, leading to changes in climate may reach catastrophic levels with time.

What are the causes of global warming?

Climate scientists studied this phenomenon for decades, and have a thorough analysis of the courses and the natural phenomena that affect the formation change. Shows a result he can not explain the pattern and amount of increase in temperature of the Earth Based on these factors alone, and we must take the impact of greenhouse gases generated by the human mind, greenhouse emissions from fuel combustion contribute to the worsening problem of global warming.

What are greenhouse gases?

A group of greenhouse gases generated by the rights in different ways, mostly produced by burning fossil fuels, coal and oil in cars, factories and power plants. The carbon dioxide (CO2) gas to heat the Earth more important because of the large quantities resulting from the combustion processes. Followed by methane (CH4) resulting from the fermentation processes in the food industry, agriculture and waste dumps, and nitrous oxide gas (N2O) resulting from the industry, fertilizers, gases used in refrigeration and other industrial processes, and finally the removal of forests, which store a great deal of carbon dioxide gas if remained alive.
Vary in their ability of these gases on global warming than carbon dioxide. Valmithan nitrous oxide and refrigerant gases differ in their ability to store thermal energy for carbon dioxide, the equivalent of 20 and 300, and a few thousand times, respectively. However, due to the small quantities of other gases in the atmosphere, their impact on heating the earth remains limited compared with carbon dioxide.

How do greenhouse gases to warm the earth?

Penetrating rays of the sun visible, with a relatively short wavelength, atmosphere of the Earth, and is working to heat the surface and oceans. In contrast, infrared, long wave, which is emitted from the surface of Earth and its waters back They reflect mostly from the atmosphere back to Earth absorbs and thus gradually raise the temperature above the average on an ongoing basis. Greenhouse gases and play a key role in that disturbed the balance of natural uncommon for the temperature of the earth, and increased gradually heated.

What is the increase in the concentration of greenhouse gases since 1750? It is the countries responsible for that?.

The increase in the concentration of greenhouse gases since 1750 in the following order: -

Carbon dioxide( CO2) 36%.

Methane( CH4) 148%.

Gas nitrous oxide( N2O) 18%.

It is responsible for this first-class United States and Europe, the cradle of the industrial revolution and technological progress marched rapidly after World War II, and the discovery of the enormous resources of fossil fuels coal, oil and natural gas. Is equivalent to what launched the United States from greenhouse gases alone, the total launched by South America, Africa, the Middle East, Japan, and Asia. The United States launched in 2007 seven billion tons of greenhouse gases to the atmosphere of the Earth.
And is expected to equal the emissions of greenhouse gases for the second with the industrialized world by the year 2015, and is expected to increase after the thermal pollution resulting from the developing countries in large quantities. Are expected to increase the temperature of the earth and oceans between 4 C to 8 C by the year 2100, depending on the pace of global economic growth.

What are the effects of global warming?

Melting ice One result of global warming
The Earth is warming the length and breadth, and the evidence of this abound in multiple places:
* Ice melts in each place where, especially in the north and south poles. This will have a significant and serious implications for water in this planet, and rising sea levels and ocean, and will disappear as a result of a large number of islands scattered in the oceans, and coastal countries will lose an important part of its territory, which would reflect negatively on the productivity of the economic and tourist sites and cultural rights. It is expected sea level rise between 20 and 50 cm by the year 2100.

Evidence abound that the world is currently in between (2010 -2000) to climate change, and hotter temperatures not seen in the ground in its history. As a result:-

1 - increased flooding and destructive storms.
2 - Increased periods of prolonged drought, and breadth of the phenomenon of desertification, the spread of fires.
3 - catastrophic changes in environments of plant and animal populations, which will lead to the extinction of some species of animals like a bear, polar, for example, decreased numbers of some of the other penguins in Antarctica, which decreased in number from 32000 to 11000 in 30 years.
4 - the spread of epidemics and famine, widespread and dangerous.
5 - breeding of insects out of control and destruction of forests.
6 - the destruction of coral reefs and marine environments.
7 - predicting the demise of Arctic ice within (7-5) years.

What can we do?

To save our planet from a similar fate we have to do a variety of the most important actions:-

1-That the United Nations to develop binding agreements for all States, also tried at the Copenhagen conference which concluded in 2009-12-18, but failed because of differences between the advanced industrial countries and developing countries and the dominance of monopolies and capital on the policies of the participating countries.
2-Development of alternative sources of clean energy: as wind, sun, and the generation of electrical energy from water resources and dams.
3-Development of new technologies developed a highly efficient use of energy to become a pillar of the global economy.
4-Every State's obligation to maintain strict legislation on the environment and cleanliness at all levels.
5-The upbringing and education of generations to be on the high level of commitment to environmental conservation and maintenance.

Let us work together to save our beautiful planet and civilization of humanity

Solar energy

Solar energy:- a source of inexhaustible energy, but it is up to us are scattered and need to be a modern technology (solar cells) for compilation and use of, a source of clean is not caused by any use of gas or products harmful to the environment as is the case in other fuels.
The definition of solar cells: - Transformers Voltazaviip convert sunlight directly into electricity, a semiconductor and sensitive scan and surrounded by front and rear cover conductor of electricity.

Benefited rights since the foot of the solar radiation energy directly in many applications drying crops and heating homes. Also used in other areas, have been burned Archimedes Rummani Navy in the war in 212 BC by focusing solar radiation on the vessels of the enemy by the hundreds of metal armors. In the Babylonian priests, the women were using verse gold polished mirrors to concentrate solar radiation to get a shot.
Has also been established in the early first century AD the current international terminal for irrigation, solar energy was mediated by working for five hours per day, near Cairo.
Man tried long ago to take advantage of solar energy exploitation, but as far as small and limited but the great development of technical and scientific progress reached by man opened up a new science in the field of solar energy utilization.

Solar energy conversion:-

Can convert solar energy into electrical energy and thermal energy through the photoelectric conversion mechanisms and the thermal conversion of solar energy, has been manufacturing many models of the solar cells can produce electricity in a scientific manner and is characterized by solar cells that it does not include moving parts or pieces, which do not consume fuel or air pollution and life is long and require little maintenance. Achieved the best use of this technology under the console application of solar radiation (solar module) without any optical concentrators, lenses and therefore can be installed on the roofs of buildings to serve in the production of electricity, efficiency is usually estimated at about 20%, while the rest can be utilized to provide heat for heating and water heating.
The applications of solar water heaters are the most prevalent in the area of the thermal conversion of solar energy. Followed by the most important solar dryers that are frequently used in drying some crops such as dates, as well as others can take advantage of the thermal energy to cook food.
The storage of solar energy research of the most important areas of development needed in the application of solar energy and spread of a wide range, where solar energy is available but it is not at hand and not free, real ones, the words on the equipment used to convert electromagnetic energy into electrical energy or heat, as well as storage if necessary.

Applications on the use of solar energy:-

1-Urban planning and architecture: the design of buildings based on the exploitation of solar energy so that it may hand the south for light and warmth.
2-Plant cultivation and horticulture: machinery used in the management of water pumping, crop drying and hatching chickens and drying chicken manure, greenhouses (glass).
3-Solar lighting: The use of natural sunlight from the most commonly used types of lighting throughout the ages.
4-Heat of the sun: The use of techniques that rely on the exploitation of heat from the sun to heat water and space heating and cooling and the process of generating heat.
5-Water treatment: solar distillation is used to make salt water, water, wheat fit for drinking.
6-Solar cooking: The solar cooker is a device that uses sunlight for cooking, drying and pasteurization. The types are divided into three categories: funds that traps heat and stoves, curved concentrators (Barrapolaaks) and stoves in the form of flat panels.
7-Heat treatment: The means to focus solar energy can provide heat treatment for industrial and commercial.
8-Electricity generation: You can convert sunlight directly into electricity using adapters Voltodoiip (PV) and the process of concentration of solar power (CSP) and many other experimental methods.
9-Solar-powered cars.

Methods of storing solar energy:-

Can not get on solar energy during the night. Thus, energy storage is necessary because modern energy systems need to be a source of energy is available all the time, the thermal mass systems can store solar energy in the form of heat at temperatures useful for domestic purposes, either daily or throughout the season, is a variable-phase materials such as paraffin wax and Glauber's salt sources of thermal energy storage as well. These materials are not expensive and ready to use and can reach temperatures useful for domestic purposes (approximately 64 degrees Celsius), can store solar energy is very high temperatures using molten salts.

Robot Technology

Robots: - machine is able to carry out operations of pre-programmed. The robot completed these events either at the instigation and direct control of the rights or at the instigation of the software.

The word robot was introduced for the first time in a play by Czech playwright Karl Chapik in 1920. The title of the play and then robots Global. It means in the Czech language of hard work,Experts and engineers succeeded in providing a variety of automated systems for many industries. Because of the enormous development of computers and artificial intelligence techniques, Man on the verge of major breakthroughs in space science by robots.

Overview of the robot automation:-

There is controversy about the precise definition of robot is no other car or plane with a remote control robot, because it lacks a way of thinking and decision-making itself, and provides some example that if the robots can be carried out pre-established program moves away from the barrier two steps back, for example, the trend to the right or left and continue to progress, this can be considered a real robot, there are many types of robots, including those used in the industrial sector, which is an automated devices can be adapted and re-programmed and used for many purposes, can the movement of three or more axes and using this type of companies the major industrial minerals for the purpose of meat, and some forms of robots that is capable of movement and leadership, including the unmanned aircraft (instrument flight), Albraidator and aircraft self-control using artificial neural networks, for example, which is Alansaltan sent by NASA in 2004 to the surface of Mars months, the Robert animation.

There are robots that is able to reassemble itself in a semi-autonomous, for example, shrinking its size to pass through a narrow tunnel and this Alansen automation in the model contains many links with the CPU, memory, and receivers able to have some of these movements, similar to rubber to contain on a flexible, There are also types of robots are household chores, and children learn and play chess. This type of robot referred to as social robot, we can say that the robot is a device or machine that could replace rights in some situations. Morphology depends on the task that was made for.

The idea of robots in ancient history:-

Roots robot modern, automatic equipment was invented in the distant past and called it "self-propelled machines." In the era of the ancient Egyptians around 1500 BC there was a statue of the king Memnon Isdrosouatta beautiful in the morning. In Greece - in the fourth century BC. M. - Invented Orkitas mathematician, Dove mechanism could fly. In the third century BC, invented many devices Stisebeos mechanism, including a musical instrument resembling an organ-water and water clock.
In Europe in the Middle Ages, philosophers interested Vajnos Albert and Roger Bacon's great interest in machinery movement, but some of them do well. The invention of the time the mechanism in the late thirteenth century, to supply machinery self-propelled mechanical force necessary, and so could be the invention of the clock bells ringing to announce the time. In the eighteenth century, toy makers produced a large number of self-propelled machines which were in human form and can talk and play music and write and even play chess.

George the robot:-

George was one of the first robot that have emerged. George led the aircraft most of the time, it's autopilot was invented by electrical engineer Elmer Sperry Sperry, founder of the Hi and the model was the first automatic pilot is connected with the magnetic compass device for reading and a rise indicates the direction in which the plane, and leave the responsibility for human pilots fly to George the robot, and once to stabilize the plane in the right direction for her, and notes any change George vertical or horizontal flight and take corrective action immediately.
In 1954 designed the first industrial robot was the name of its inventor, George, too, was designed by architect George Difol.

Robot movement:-

Legs of the robot contains advanced in some cases more than 40 sensor and the mechanical device and the sensors continuously measure the pressure distribution on the legs hanging has been in the industry in 2004 robot legs can be attached to the legs of Rights to help transform ordinary human steps to giant steps quickly and without making muscular effort of man, was named this invention the external structure and mud weighing about 50 kg.
The robot is to coordinate the steps in steps Rights simulates a very complex process and it would be easier to use wheels instead of legs, Alansalat types of sophisticated use of moving legs and SIGMO robot QRIO robot and robot ASIMO.

The tradition of the most difficult leg of the tradition of human human hand, and the main problems that correspond to the problem of robot-makers balance, it is best to have a robot four legs instead of two. The idea of production machinery can walk and move the idea of recent. He used some of them over the years in agricultural operations and drilling. Among the most famous of these machines moving truck with four legs produced by General Electric Company of the U.S. Army, and controls the driver in the truck to move his hands and legs legs that connect the truck.

Types of robot:-

The robot can be divided according to their respective characteristics and the target which was prepared for it. Robot may be designed to perform specific work in high-precision, or a certain number of work but less precisely, and can of course be re-programmed robot to perform different or pursuant to act in a manner different from what it had to do, if its central permit. For example, can modify a task the robotic arm used in the factories of metal cutting to the assembled, welded, Tchigaha, pregnancy, or even to become a machine used in the passenger entertainment of visitors to the factory, while robots load and transport it can be modified only to the compilation of its Printed Circuit Board .

Advantages and disadvantages of the robot:-

Robot offers several advantages including, for example: greater productivity, effective use of the equipment, low labor costs, improved flexibility, work is done in a shorter time, flexibility and ease of programming, the ability to work in hazardous conditions, improved quality of premises and production, investment returns good, better precision in performance.
Have a number of shortcomings and deficiencies, such as unemployment, manual workers and a lot of technical problems as the other use. Especially in the fields of artificial intelligence or machine vision.

In the cinema and science fiction to imagine a robot probability of a threat to the future of rights because of artificial intelligence, but on the ground, the danger resulting from the Artificial Intelligence is almost non-existent due to the fact that research in this area is still at the stage of beginning. However, the use of these systems on the robot war or give the controls on the equipment may pose a serious threat to human life, regardless of how the development of intelligent systems Alistai them. The existing application.

The Volcano

The definition of the volcano:-Is that place from which he graduated or emits materials Alzirip warm with fumes and gases associated with the depth of the earth's crust and occurs during the nozzles or cracks. And accumulate molten material or by type of flow to form the different land forms, including conical hills or high volcanic mountains.

Volcanoes of the unique natural phenomena called the attention of rights since the League and they play a great role in geological processes that affect the evolutionary history of the earth's crust and shape. This is because most parts of the earth's crust affected Alandfaip underwent operations in its composition to the contribution of operations Alandfaip. According to a study to identify the volcanic centers of study of earthquakes and volcanoes, a branch of geology, which has become known as a stand-alone volcanology.

Parts of volcanoes:-

1-Cone-shaped mountain: composed of the wreckage of a rocky material thrown from the volcano crater was all or some of them in molten state.
2-Mouth: It is a cavity almost round shape at the top of the cone, width ranging from a few thousand meters. And flowed from the crater at intervals of gas and the masses of rock, shells and lava and molten materials.
3-Chimney or reed: a channel extending from the bottom of the crater to the bottom where you connect a bakery magma underground. And push through volcanic material to the crater. Sometimes known as the neck of the volcano.

Types of volcanic materials:-

1-Rocky debris: emerge as a result of volcanic eruptions rocky debris into different types and sizes usually in the first period of volcanic eruptions.
2-Gases: Graduated from volcanic activity during the gas water vapor, which derives a great quantities of a component of the huge clouds mixed with dust and other gases. Is building these fumes, causing the heavy rain falling in the vicinity of the volcano.
3-Lava: The liquid clusters "instead of volcanoes, and has a temperature between 1000 and 1200, the two types: -
*LAVA lightweight, light colored.
*LAVA heavy dark color.

Forms of volcanoes:-

1- Volcanic rock debris:
Vary in shape depending on the volcanic cone material that consists of them. If the cone composed entirely of rock debris, we found a high steep for the space occupied by the base.
2-Volcanic plateau:
Arise as a result of exit and lava accumulation around the main crater and look like low-rise for the large area occupied by the rules. The peaks seem like Bhiab convex.
3-Volcanoes stratified:
Stratified volcanic common type of existence, is in the form of ex-center types and composed of materials Mkrotadtha debris flows, lava rock and directed by the volcano eruption, while ease.

The geographical distribution of volcanoes:-

1-omain that surrounds the Pacific Ocean and coastline, which is sometimes known as Ring of Fire.
2-There are many volcanoes in the Pacific Ocean itself and some great grew up in a huge hall and appeared towering above the level of its waters. Volcanoes, including the Hawaiian Islands, which is based norms in the ocean at a depth of 5000 m, and rises above the water surface of more than 4000 m.
3-Southern Europe, overlooking the Mediterranean and the adjacent islands. The most active volcanoes here Vesuvius near Naples, Italy, and Sicily, and Aetna Islands Astro Mpule (Lighthouse of the Mediterranean) in the islands of Lipari.
4-Highlands of Western Asia and months and Ararat volcanoes Aliuzenz.
5- Scale-east of Africa and months Brkinh Kilimanjaro. Me.

Effects of volcanoes:-

1-In the formation of the Earth's surface:
Above that we can discern the effects of volcanoes in the formation of the Earth's surface is created majestic mountains and plateaus spacious. When subside arise in the cavities of lakes in those pores rainforest.
2-In human activity:
Strange that a man did not played accommodation near volcanoes in order to be safe from the dangers, seen live near them, but on the slopes as well. Vesuvius volcano, surrounded by villages and towns and covered with fruit groves, vineyards and orchards spread over all of its aspects until near the top. The Agriculture also on the slopes of a volcano (Athina) in the island of Sicily in 1200 to a height in the fertile soil is composed of black basalt that spilled over the region during the historical periods.

The famous island of Java volcanoes rebellious and active volcanoes than virtually every volcano in the world in the amount of spills and Alloafez that flowed from them since 1500, however, we find the island full of population, it is the densest points of the world's agricultural population to the area and home to about 75 million people due to fertility as we have already volcanic soil, was established by the Department of Volcanology and function to predict volcanic eruptions and warn the population before the volcanic eruptions, which reduces the risk of their occurrence.

The Biofuels(Green Gold)

The definition of biofuels:-Is a clean fuel production depends mainly on the conversion of biomass, whether represented in the form of grains and agricultural crops such as maize, sugar cane or in the form of oils and animal fats such as soybean oil and palm oil to ethanol or alcohol organic diesel, which means it can be used for lighting and operation of vehicles And the Department of generators.

The current biofuels:-

However, the major advantage of biofuels that will hopefully develop and expand, it also can be produced from waste, animal waste and plant residues, whether or animals and their droppings were from rice straw and sawdust, as can be produced from algae and aquatic plants and other fast-growing non-food items such as the value of jatropha and jojoba.

In terms of the possibilities and benefits of currently available sources of renewable energy, whether from the sun, wind, waves or other remains of biofuels, despite the controversy surrounding him, is the most capacity to support global energy security, and this for several reasons:-

First: - its cheap cost and the possibility of production at any time and any part of the land, because of the availability of its raw materials and is not constrained by any geographical or natural factors, a major feature missing from other renewable sources of energy such as solar energy, which are linked by the brightness of the sun, and wind energy can not be provided throughout the months of the year, and hydropower that are related to the existence waterways and coasts freely, which is not available for all countries.
Second: - The cleanliness of the source and did not harm the environment or climate and growing so in hopes of ridding the world of a large part of the current environmental problems, Vmahroqat biofuels compared with fossil fuels is characterized by the launch of less content of carbon dioxide, the leading cause of global warming, and lead , one of the toxic and carcinogenic and other chronic diseases, and the majority of oils, biofuels, degrade gradually and automatically, which means that impact negatively on the quality of the environment and the media surrounding ecosystems.

The reality of these benefits was not strange that the world is witnessing a real boom in the biofuels industry over the past years, in America's largest producers of fuel ethanol production, for example, jumped from 53 million liters in 2003 to 280 million liters in 2005, and in Brazil Sweden and Germany resulted in growth of productive capacity to its transformation to exporters of the fuel, and, some have called the proposal to establish a special assembly in these countries and all other countries exporting biofuels, the Organization of energy, particularly along the lines of OPEC oil, the world growth rate in the energy industry of biofuels about 15% annually, and is expected to increase global demand by 30% during the coming period, all indicators are very important, and illustrates the status and prosperity achieved by the industry.

Dreams biofuels promised:-

Established that the increasing demand for biofuels and the viability of this renewable source to fill the existing vacuum in energy sources will be based on the most important result: -
First - is the throne of Achah energy future green color instead of the current black. This means the other hand, fading star nations and kingdoms of many economic, as long as the oil sits Good stock and boosted its coffers, and also means other emerging high power.
Secondly - to uphold the value of agricultural land and the creation of a new renaissance of global agricultural and comprehensive, it could biofuels and increasing demand for agricultural products, contribute to the rehabilitation of many of the deserts and arid lands, and boost agricultural production around the world and expanded horizontally and vertically.

Some of the problems of biofuels expected:-

1-Agricultural land-use change and rush towards the expected conversion of productive agricultural fields of food crops to large mines for energy crops promised, and the consequent disruption of the world's agricultural biodiversity and forests and encroaching on protected green areas, increased soil erosion, and high levels of water pollution and air because of the large quantities of pesticides and fertilizers required for cultivation of energy crops especially maize.
2-For developing countries dependent on imports for its food needs of poor countries usually receive grants and international assistance in the form of food aid, these fears are no doubt will turn into nightmares spirits because of the escalating prices of food crops as a result of the growing demand for grain and agricultural products, and due to lack of the surplus of oil exporters, which in turn threatens global food security directly.
3-Escalation of the conflict on water resources due to the increasing need for water, both for use in irrigation of crops, corn and sugar cane producers of energy, or in the process of biofuel production itself, where the production cost, for example one liter of ethanol from corn is about 4 liters full of water.

Based on this expected "World Institute for Water Resources Management", in a recent study it, to face both China and India, for example in the scarce water sources by the year 2030, if they continued to present their plans to produce biofuels.

However, it can not of course be quite so gloomy or negative when talking about the production of biofuels from waste plant, animal or agricultural wastes and other wastes, because of this harmony with environmental safety and food security of the world, but this trend, will depend on in any case the development of current technology manufacturer of biofuels.

Trends Mtaxan fully represent the dreams and nightmares of this emerging industry, and separated by only a hair one minute, is in the quality of biomass to be used in the production of biofuels in the future, whether they are derived from the basic food crops such as corn, wheat, soybeans, food and all the poor people of the world, or source of animal and vegetable waste was not lacking in the environment, and human needs.

Technologies 2010 mobile phones

Faster, cheaper and contains additional functionality

Mobile phones have become the primary communication means for the user's personal or corporate, shall be revealed and unveiled in 2010 for more features and innovations in the world of mobile phones.
Smart phones and gained a better position in the mobile phone market with larger screens
And their ability to access the Internet at higher speeds.
Says Andy Rubin, who is in the draft operating system "Android" of search engine Google
Famous on the Internet that there are already mobile phones on the market contain chips up
Speed of one gigahertz.
He predicted, saying that "in the near future we will have mobile phones at speeds of 2 processors GHz, which exceeds the speeds of many laptops, "he said, adding that the computer
Is no longer a need to review the e-mail or search for specific information on emergency
Or visit the Web site Facebook for social networking. According to the German Association of TechnologyInformation and telecommunications and new media) Petkom (The number of mobile phones in theGermany will increase this year by 47 percent to 2, 8 million units.
And increased rates of wireless data transmission via mobile phones in Germany four times
Approximately in 2009 to up to forty million GB, hence not surprising that seeks
More mobile phone manufacturers to get a piece of the pie.

The company is hoping the software giant Microsoft to increase its stake in the mobile phone marketThrough the new operating system "Windows 7" for mobile.
The new program appeared for the first time at the World Conference for mobile, which was held recently in the cityBarcelona, Spain, and the advantage of being easier to use than the old version and Windows Mobile 5 t. 6.
This program aims to facilitate the transfer of data and arranged by mobile phone.
Seeks Google's part to compete with Microsoft in the world of mobile phonesDuring the operating system "Android."
Rubin says that one year ago, the use of operating system Android is limited to phone
G 1 (one phone models) HP. T. C (; today, this system became available on the
27 mobile phone in 59 countries).

Technologies of modern agriculture

Agriculture refers to the production of food and goods through agriculture and forest industry, agriculture is the key to development that led to the emergence of civilization, with animal husbandry.
Agriculture includes many types of disciplines and techniques, including ways to expand the land suitable for the growth of plants by digging canals and other forms of irrigation. Cultivation of crops on arable land for agriculture and rural grazing of livestock on rangeland remain the basis for agriculture.

Modern agriculture and plant breeding, pesticides and fertilizers, and technological progress has increased sharply from planting crops, and at the same time have caused environmental damage and wide-ranging and negative effects on human health.
The most important agricultural products can be grouped in general in food, fiber, fuel, raw materials, medicines, stimulants, and a variety of grooming products or products of crop species. In 2000, the plants used for the development of biofuels, bio-medical materials, bio-plastics.
Since 7000 BC, and reached small-scale agriculture to Egypt. Since 7000 BC, at least sub-continent India has seen growing wheat and barley.


In the Middle Ages:-

During the Middle Ages, the farmers, j North Africa and the Near East to the development and dissemination of agricultural technologies including irrigation systems based on the principles of hydraulic and Hydrostatic, the use of devices such as waterwheels, and the use of water-raising machines, dams and reservoirs, has invented a three-field system of crop rotation during the Middle Ages to the improvement large valuable agricultural efficiency.

Modern:-

After 1492, occurred the global exchange of the previous local crops and animal breeds. The main crops involved in this exchange tomatoes, corn, potatoes, cassava, cocoa and tobacco, which are transmitted from the New World to the Old World, and several varieties of wheat, spices, coffee, cane sugar that is transferred from the Old World to the New World. The most important export animals of the ancient world to the new world are horses and dogs.
The issue of increasing agricultural production of strategic crops (cereals) at the various kinds of fundamentals, important in the development of the significant pillars of the national economy and bridge the gap between the local and global markets, reducing import costs and reduce financial dependence on other countries, hence the need to be planning for advanced technology in this area contribute to to increase local agricultural production in this area and improve the nutritional level.
Food security is important pillar of national security in any country and it is linked to people's lives and health hence the governments responsibility to provide food, either through local agricultural production or import.

Genetic engineering in agriculture:-

After it has been the development of mechanical harvesting of tomatoes in early 1960, the agricultural scientists cultivate tomatoes genetically modified to be more resistant to mechanical handling. Recently, genetic engineering is being used in different parts of the world, to create a crop other useful features.

Modified crops genetically engineered to tolerate herbicides:-

Characterized by the seeds of pesticide Raundb Reddy said with Jane resistant to herbicides was grown for its own genome, which makes plants able to withstand exposure to Gelaiovusat Roundup Ready is a trading name of the product based on Algelaiovusat, a general, non-selective Herbicide used to kill weeds. Reddy Ruandab allow seeds to farmers to grow crops that can be sprayed with Gelaiovusat to control weeds without harming crops resistance. Used crop herbicide-tolerant of the farmers in all parts of the world. Today, 92% of the area of soybeans in the United States is cultivated with plants genetically modified herbicide-tolerant.

Genetically modified crops for insect resistance:-

Other crops genetically modified crops used by farmers include resistance to insects, which have genes from soil bacteria Bacillus Teringensis that produces a substance toxic to certain insects; protect crop plants resistant to insect damage from insects, one of these crops is the Starlink corn. The other plant is insect-resistant cotton, which represents 63% of the area of cotton from the U.S.

The costs and benefits of genetically modified crops:-

Genetic engineering of plants have proved to be controversial. Many of the issues that revolve around food security, and environmental impacts have risen on the applications of genetically modified crops. For example, organisms are genetically modified questioned by some ecologists and economists from genetically modified crops are concerned with applications of genetically modified crops and seeds such as final, a genetic modification to create sterile seeds. The final seed is currently under strong international opposition and faces ongoing efforts of a global ban was to prevent farmers who use seed to save seeds for subsequent crops, which forces farmers to buy new seeds every year. As the seed-saving is a traditional practice for many farmers in both developing and developed countries, legally and genetically modified seeds force farmers to change the practices of seed-saving and buy new seeds every year.